| 1. |
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| 2. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 3. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 4. |
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| 5. |
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| 7. |
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| 8. |
- Fan, Ke, et al.
(författare)
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Amorphous WO3 induced lattice distortion for a low-cost and high-efficient electrocatalyst for overall water splitting in acid
- 2020
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Ingår i: Sustainable Energy & Fuels. - : ROYAL SOC CHEMISTRY. - 2398-4902. ; 4:4, s. 1712-1722
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Tidskriftsartikel (refereegranskat)abstract
- The development of highly active and durable catalysts for water oxidation under acidic conditions is necessary but challenging for renewable energy conversion. Ir-based catalysts are highly efficient for water oxidation in acid, but their large scale application is hindered by the high cost and scarcity of iridium. Herein, we use an amorphous WO3 induced lattice distortion (AWILD) strategy to reduce the Ir content to only 2 wt% in the final material. The optimized hybrid nitrogen-doped carbon (NC)/WO3/IrO2 can efficiently catalyze water oxidation with a low overpotential of 270 mV at 10 mA cm(-2) current density (eta (10)) and a high turnover frequency of over 2 s(-1) at 300 mV overpotential in 0.5 M H2SO4, a performance that surpasses that of commercial IrO2 significantly. Introducing the layer of amorphous WO3 between IrO2 nanoparticles and NC can distort the lattice of IrO2, exposing more highly active sites for water oxidation. The AWILD effect compensates for the lower Ir content and dramatically reduces the cost of the catalyst without sacrificing the catalytic activity. Additionally, this catalyst also exhibits high activity in acid for hydrogen evolution with only 65 mV of eta (10) attributed to the AWILD effect, exhibiting efficient bifunctionality as a Janus catalyst for overall water splitting. The AWILD approach provides a novel and efficient strategy for low-cost and highly efficient electrocatalysts for acidic overall water splitting with an extremely low content of noble metals.
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| 9. |
- Haycock, Philip C., et al.
(författare)
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Association Between Telomere Length and Risk of Cancer and Non-Neoplastic Diseases A Mendelian Randomization Study
- 2017
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Ingår i: JAMA Oncology. - : American Medical Association. - 2374-2437 .- 2374-2445. ; 3:5, s. 636-651
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Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE: The causal direction and magnitude of the association between telomere length and incidence of cancer and non-neoplastic diseases is uncertain owing to the susceptibility of observational studies to confounding and reverse causation. OBJECTIVE: To conduct a Mendelian randomization study, using germline genetic variants as instrumental variables, to appraise the causal relevance of telomere length for risk of cancer and non-neoplastic diseases. DATA SOURCES: Genomewide association studies (GWAS) published up to January 15, 2015. STUDY SELECTION: GWAS of noncommunicable diseases that assayed germline genetic variation and did not select cohort or control participants on the basis of preexisting diseases. Of 163 GWAS of noncommunicable diseases identified, summary data from 103 were available. DATA EXTRACTION AND SYNTHESIS: Summary association statistics for single nucleotide polymorphisms (SNPs) that are strongly associated with telomere length in the general population. MAIN OUTCOMES AND MEASURES: Odds ratios (ORs) and 95% confidence intervals (CIs) for disease per standard deviation (SD) higher telomere length due to germline genetic variation. RESULTS: Summary data were available for 35 cancers and 48 non-neoplastic diseases, corresponding to 420 081 cases (median cases, 2526 per disease) and 1 093 105 controls (median, 6789 per disease). Increased telomere length due to germline genetic variation was generally associated with increased risk for site-specific cancers. The strongest associations (ORs [ 95% CIs] per 1-SD change in genetically increased telomere length) were observed for glioma, 5.27 (3.15-8.81); serous low-malignant-potential ovarian cancer, 4.35 (2.39-7.94); lung adenocarcinoma, 3.19 (2.40-4.22); neuroblastoma, 2.98 (1.92-4.62); bladder cancer, 2.19 (1.32-3.66); melanoma, 1.87 (1.55-2.26); testicular cancer, 1.76 (1.02-3.04); kidney cancer, 1.55 (1.08-2.23); and endometrial cancer, 1.31 (1.07-1.61). Associations were stronger for rarer cancers and at tissue sites with lower rates of stem cell division. There was generally little evidence of association between genetically increased telomere length and risk of psychiatric, autoimmune, inflammatory, diabetic, and other non-neoplastic diseases, except for coronary heart disease (OR, 0.78 [ 95% CI, 0.67-0.90]), abdominal aortic aneurysm (OR, 0.63 [ 95% CI, 0.49-0.81]), celiac disease (OR, 0.42 [ 95% CI, 0.28-0.61]) and interstitial lung disease (OR, 0.09 [ 95% CI, 0.05-0.15]). CONCLUSIONS AND RELEVANCE: It is likely that longer telomeres increase risk for several cancers but reduce risk for some non-neoplastic diseases, including cardiovascular diseases.
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| 10. |
- He, YQ, et al.
(författare)
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A polygenic risk score for nasopharyngeal carcinoma shows potential for risk stratification and personalized screening
- 2022
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13:1, s. 1966-
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Tidskriftsartikel (refereegranskat)abstract
- Polygenic risk scores (PRS) have the potential to identify individuals at risk of diseases, optimizing treatment, and predicting survival outcomes. Here, we construct and validate a genome-wide association study (GWAS) derived PRS for nasopharyngeal carcinoma (NPC), using a multi-center study of six populations (6 059 NPC cases and 7 582 controls), and evaluate its utility in a nested case-control study. We show that the PRS enables effective identification of NPC high-risk individuals (AUC = 0.65) and improves the risk prediction with the PRS incremental deciles in each population (Ptrend ranging from 2.79 × 10−7 to 4.79 × 10−44). By incorporating the PRS into EBV-serology-based NPC screening, the test’s positive predictive value (PPV) is increased from an average of 4.84% to 8.38% and 11.91% in the top 10% and 5% PRS, respectively. In summary, the GWAS-derived PRS, together with the EBV test, significantly improves NPC risk stratification and informs personalized screening.
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| 11. |
- Ren, Luyao, et al.
(författare)
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Quartet DNA reference materials and datasets for comprehensively evaluating germline variant calling performance
- 2023
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Ingår i: Genome Biology. - : BioMed Central (BMC). - 1465-6906 .- 1474-760X. ; 24:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Genomic DNA reference materials are widely recognized as essential for ensuring data quality in omics research. However, relying solely on reference datasets to evaluate the accuracy of variant calling results is incomplete, as they are limited to benchmark regions. Therefore, it is important to develop DNA reference materials that enable the assessment of variant detection performance across the entire genome.RESULTS: We established a DNA reference material suite from four immortalized cell lines derived from a family of parents and monozygotic twins. Comprehensive reference datasets of 4.2 million small variants and 15,000 structural variants were integrated and certified for evaluating the reliability of germline variant calls inside the benchmark regions. Importantly, the genetic built-in-truth of the Quartet family design enables estimation of the precision of variant calls outside the benchmark regions. Using the Quartet reference materials along with study samples, batch effects are objectively monitored and alleviated by training a machine learning model with the Quartet reference datasets to remove potential artifact calls. Moreover, the matched RNA and protein reference materials and datasets from the Quartet project enables cross-omics validation of variant calls from multiomics data.CONCLUSIONS: The Quartet DNA reference materials and reference datasets provide a unique resource for objectively assessing the quality of germline variant calls throughout the whole-genome regions and improving the reliability of large-scale genomic profiling.
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| 12. |
- Adnane, Bouchaib, et al.
(författare)
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Photoluminescence study of nanocrystalline-Si(Ge) embedded in mesoporous silica
- 2009
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Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 53:8, s. 862-864
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Tidskriftsartikel (refereegranskat)abstract
- Photoluminescence (PL) properties of mesoporous silica (MS) samples incorporated with Si or Ge nanocrystals (nc) have been investigated with various excitation powers and post-RTA processes. The analysis of experimental results revealed a superlinear intensity dependence (m = 1.7) in the MS reference sample without nanocrystals, while a sublinear behavior (m = 0.8) is observed for the nc-Si in MS. It thus suggests the same recombination responsible for the luminescence at similar to 2.75 eV for both samples, but different kinetic limitations for the carrier transfer processes. Si nanocrystals play in this case an important role in generating more photo-excited carriers, enhancing the PL intensity.
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| 13. |
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| 14. |
- Blunden, Jessica, et al.
(författare)
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State of the Climate in 2012
- 2013
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 94:8, s. S1-S258
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Tidskriftsartikel (refereegranskat)abstract
- For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.
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| 15. |
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| 16. |
- Chow, Wah Soon, et al.
(författare)
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Quantifying and monitoring functional photosystem II and the stoichiometry of the two photosystems in leaf segments : approaches and approximations
- 2012
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Ingår i: Photosynthesis Research. - Dordrecht : Springer. - 0166-8595 .- 1573-5079. ; 113:1-3, s. 63-74
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Forskningsöversikt (refereegranskat)abstract
- Given its unique function in light-induced water oxidation and its susceptibility to photoinactivation during photosynthesis, photosystem II (PS II) is often the focus of studies of photosynthetic structure and function, particularly in environmental stress conditions. Here we review four approaches for quantifying or monitoring PS II functionality or the stoichiometry of the two photosystems in leaf segments, scrutinizing the approximations in each approach. (1) Chlorophyll fluorescence parameters are convenient to derive, but the information-rich signal suffers from the localized nature of its detection in leaf tissue. (2) The gross O-2 yield per single-turnover flash in CO2-enriched air is a more direct measurement of the functional content, assuming that each functional PS II evolves one O-2 molecule after four flashes. However, the gross O-2 yield per single-turnover flash (multiplied by four) could over-estimate the content of functional PS II if mitochondrial respiration is lower in flash illumination than in darkness. (3) The cumulative delivery of electrons from PS II to P700(+) (oxidized primary donor in PS I) after a flash is added to steady background far-red light is a whole-tissue measurement, such that a single linear correlation with functional PS II applies to leaves of all plant species investigated so far. However, the magnitude obtained in a simple analysis (with the signal normalized to the maximum photo-oxidizable P700 signal), which should equal the ratio of PS II to PS I centers, was too small to match the independently-obtained photosystem stoichiometry. Further, an under-estimation of functional PS II content could occur if some electrons were intercepted before reaching PS I. (4) The electrochromic signal from leaf segments appears to reliably quantify the photosystem stoichiometry, either by progressively photoinactivating PS II or suppressing PS I via photo-oxidation of a known fraction of the P700 with steady far-red light. Together, these approaches have the potential for quantitatively probing PS II in vivo in leaf segments, with prospects for application of the latter two approaches in the field.
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| 17. |
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| 18. |
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| 19. |
- Ganat, Yosif M., et al.
(författare)
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Identification of embryonic stem cell-derived midbrain dopaminergic neurons for engraftment
- 2012
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Ingår i: Journal of Clinical Investigation. - 0021-9738. ; 122:8, s. 2928-2939
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Tidskriftsartikel (refereegranskat)abstract
- Embryonic stem cells (ESCs) represent a promising source of midbrain dopaminergic (DA) neurons for applications in Parkinson disease. However, ESC-based transplantation paradigms carry a risk of introducing inappropriate or tumorigenic cells. Cell purification before transplantation may alleviate these concerns and enable identification of the specific DA neuron stage most suitable for cell therapy. Here, we used 3 transgenic mouse ESC reporter lines to mark DA neurons at 3 stages of differentiation (early, middle, and late) following induction of differentiation using Hes5::GFP, Nurr1::GFP, and Pitx3::YFP transgenes, respectively. Transplantation of FACS-purified cells from each line resulted in DA neuron engraftment, with the mid-stage and late-stage neuron grafts being composed almost exclusively of midbrain DA neurons. Mid-stage neuron cell grafts had the greatest amount of DA neuron survival and robustly induced recovery of motor deficits in hemiparkinsonian mice. Our data suggest that the Nurrl(+) stage (middle stage) of neuronal differentiation is particularly suitable for grafting ESC-derived DA neurons. Moreover, global transcriptome analysis of progeny from each of the ESC reporter lines revealed expression of known midbrain DA neuron genes and also uncovered previously uncharacterized midbrain genes. These data demonstrate remarkable fate specificity of ESC-derived DA neurons and outline a sequential stage-specific ESC reporter line paradigm for in vivo gene discovery.
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| 20. |
- Goedecke, Julia H., et al.
(författare)
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Ethnic differences in hepatic and systemic insulin sensitivity and their associated determinants in obese black and white South African women
- 2015
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 58:11, s. 2647-2652
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Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesis There is evidence to suggest that ectopic fat deposition in liver and skeletal muscle may differ between black and white women resulting in organ-specific differences in insulin sensitivity. Accordingly, the aim of the study was to examine ethnic differences in hepatic and peripheral insulin sensitivity, and the association with hepatic and skeletal muscle lipid content, and skeletal muscle gene expression. Methods In a cross-sectional study including 30 obese premenopausal black and white women, body composition (dual energy x-ray absorptiometry), liver fat and skeletal muscle (soleus and tibialis anterior) fat accumulation (proton-magnetic resonance spectroscopy), skeletal muscle gene expression, insulin sensitivity (two-step isotope labelled, hyperinsulinaemic-euglycaemic clamp with 10 mU m(-2) min(-1) and 40 mU m(-2) min(-1) insulin infusions), and serum adipokines were measured. Results We found that, although whole-body insulin sensitivity was not different, obese white women presented with lower hepatic insulin sensitivity than black women (% suppression of endogenous glucose production [% supp EGP], median [interquartile range (IQR)]: 17 [5-51] vs 56 [29-100] %, p = 0.002). While liver fat tended to be lower (p = 0.065) and skeletal muscle fat deposition tended to be higher (p = 0.074) in black compared with white women, associations with insulin sensitivity were only observed in black women (% supp EGP vs liver fat: r = -0.57, p < 0.05 and % supp EGP vs soleus fat: r = -0.56, p < 0.05). Conclusions/interpretation These findings may suggest that black women are more sensitive to the effects of ectopic lipid deposition than white women.
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| 21. |
- Gong, Ze, et al.
(författare)
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The Association Between Quadriceps Strength and Synovitis in Knee Osteoarthritis : An Exploratory Study From the Osteoarthritis Initiative
- 2023
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Ingår i: The Journal of rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 50:4, s. 548-555
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The aim of this study was to explore the association between quadriceps strength and synovitis in knee osteoarthritis (KOA). METHODS: This study was derived from the Osteoarthritis Initiative (OAI), which recruited adults from the OAI cohort with or at risk of KOA. Knees with complete records of isometric quadriceps strength and effusion-synovitis and Hoffa-synovitis assessments were included. Quadriceps strength was measured isometrically at baseline. Effusion-synovitis and Hoffa-synovitis were measured using the Magnetic Resonance Imaging Osteoarthritis Knee Score at baseline and at 1-year and 2-year follow-ups. Generalized estimating equations were used to analyze the associations of baseline quadriceps strength with changes in effusion-synovitis and Hoffa-synovitis in multivariable analyses. Additionally, analyses were stratified by synovitis-driven inflammatory phenotypes. RESULTS: A total of 1513 knees were included in this study. In total, 61% of the subjects were female; subjects had an average age of 61.9 (SD 8.8) years and a mean BMI of 29.4 (SD 4.7). Regarding the whole population, baseline quadriceps strength was negatively associated with baseline effusion-synovitis and follow-up changes in effusion-synovitis (odds ratio [OR] 0.77-0.86), but no significant association was observed in terms of Hoffa-synovitis. Stratified by synovitis-driven inflammatory phenotype, baseline quadriceps strength was significantly associated with follow-up changes in effusion-synovitis-but not in Hoffa-synovitis-in the population with existing effusion-synovitis (OR 0.75-0.79). CONCLUSION: Higher baseline quadriceps strength was negatively associated with changes in effusion-synovitis-but not in Hoffa-synovitis-especially in the population with existing effusion-synovitis. Our findings suggested a potential protective role of the quadriceps in effusion-synovitis.
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| 22. |
- Guo, Di, et al.
(författare)
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Cholecystokinin-like peptide mediates satiety by inhibiting sugar attraction
- 2021
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 17:8
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Tidskriftsartikel (refereegranskat)abstract
- Feeding is essential for animal survival and reproduction and is regulated by both internal states and external stimuli. However, little is known about how internal states influence the perception of external sensory cues that regulate feeding behavior. Here, we investigated the neuronal and molecular mechanisms behind nutritional state-mediated regulation of gustatory perception in control of feeding behavior in the brown planthopper and Drosophila. We found that feeding increases the expression of the cholecystokinin-like peptide, sulfakinin (SK), and the activity of a set of SK-expressing neurons. Starvation elevates the transcription of the sugar receptor Gr64f and SK negatively regulates the expression of Gr64f in both insects. Interestingly, we found that one of the two known SK receptors, CCKLR-17D3, is expressed by some of Gr64f-expressing neurons in the proboscis and proleg tarsi. Thus, we have identified SK as a neuropeptide signal in a neuronal circuitry that responds to food intake, and regulates feeding behavior by diminishing gustatory receptor gene expression and activity of sweet sensing GRNs. Our findings demonstrate one nutritional state-dependent pathway that modulates sweet perception and thereby feeding behavior, but our experiments cannot exclude further parallel pathways. Importantly, we show that the underlying mechanisms are conserved in the two distantly related insect species.
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| 23. |
- Han, Hedong, et al.
(författare)
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Dose-response relationship between dietary magnesium intake, serum magnesium concentration and risk of hypertension : a systematic review and meta-analysis of prospective cohort studies
- 2017
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Ingår i: Nutrition Journal. - : BioMed Central. - 1475-2891. ; 16
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Forskningsöversikt (refereegranskat)abstract
- Background: The findings of prospective cohort studies are inconsistent regarding the association between dietary magnesium intake and serum magnesium concentration and the risk of hypertension. We aimed to review the evidence from prospective cohort studies and perform a dose-response meta-analysis to investigate the relationship between dietary magnesium intake and serum magnesium concentrations and the risk of hypertension.Methods: We searched systematically PubMed, EMBASE and the Cochrane Library databases from October 1951 through June 2016. Prospective cohort studies reporting effect estimates with 95% confidence intervals (CIs) for hypertension in more than two categories of dietary magnesium intake and/or serum magnesium concentrations were included. Random-effects models were used to combine the estimated effects.Results: Nine articles (six on dietary magnesium intake, two on serum magnesium concentration and one on both) of ten cohort studies, including 20,119 cases of hypertension and 180,566 participates, were eligible for inclusion in the meta-analysis. We found an inverse association between dietary magnesium intake and the risk of hypertension [relative risk (RR) = 0.92; 95% CI: 0.86, 0.98] comparing the highest intake group with the lowest. A 100 mg/day increment in magnesium intake was associated with a 5% reduction in the risk of hypertension (RR = 0.95; 95% CI: 0.90, 1.00). The association of serum magnesium concentration with the risk of hypertension was marginally significant (RR = 0.91; 95% CI: 0.80, 1.02).Conclusions: Current evidence supports the inverse dose-response relationship between dietary magnesium intake and the risk of hypertension. However, the evidence about the relationship between serum magnesium concentration and hypertension is limited.
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| 24. |
- Jia, Xiaoyu, et al.
(författare)
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Chemical and Structural Engineering of Gelatin-Based Delivery Systems for Therapeutic Applications : A Review
- 2024
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 25:2, s. 564-589
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Forskningsöversikt (refereegranskat)abstract
- As a biodegradable and biocompatible protein derived from collagen, gelatin has been extensively exploited as a fundamental component of biological scaffolds and drug delivery systems for precise medicine. The easily engineered gelatin holds great promise in formulating various delivery systems to protect and enhance the efficacy of drugs for improving the safety and effectiveness of numerous pharmaceuticals. The remarkable biocompatibility and adjustable mechanical properties of gelatin permit the construction of active 3D scaffolds to accelerate the regeneration of injured tissues and organs. In this Review, we delve into diverse strategies for fabricating and functionalizing gelatin-based structures, which are applicable to gene and drug delivery as well as tissue engineering. We emphasized the advantages of various gelatin derivatives, including methacryloyl gelatin, polyethylene glycol-modified gelatin, thiolated gelatin, and alendronate-modified gelatin. These derivatives exhibit excellent physicochemical and biological properties, allowing the fabrication of tailor-made structures for biomedical applications. Additionally, we explored the latest developments in the modulation of their physicochemical properties by combining additive materials and manufacturing platforms, outlining the design of multifunctional gelatin-based micro-, nano-, and macrostructures. While discussing the current limitations, we also addressed the challenges that need to be overcome for clinical translation, including high manufacturing costs, limited application scenarios, and potential immunogenicity. This Review provides insight into how the structural and chemical engineering of gelatin can be leveraged to pave the way for significant advancements in biomedical applications and the improvement of patient outcomes.
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| 25. |
- Jia, Xiaomin, et al.
(författare)
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Single crystal metal-organic framework constructed by vertically self-pillared nanosheets and its derivative for oriented lithium plating
- 2021
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Ingår i: Cuihuà xuébào. - : Elsevier BV. - 0253-9837 .- 1872-2067. ; 42:9, s. 1553-1560
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Tidskriftsartikel (refereegranskat)abstract
- This vertically self-pillared (VSP) structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction kinetics. Here, we prepare a single crystal metal-organic framework (MOF), employing the ZIF-67 structure as a proof of concept, which is constructed by vertically self-pillared nanosheets (VSP-MOF). We further converted VSP-MOF into VSP-cobalt sulfide (VSP-CoS2) through a sulfidation process. Catalysis plays an important role in almost all battery technologies; for metallic batteries, lithium anodes exhibit a high theoretical specific capacity, low density, and low redox potential. However, during the half-cell reaction (Li++e=Li), uncontrolled dendritic Li penetrates the separator and solid electrolyte interphase layer. When employed as a composite scaffold for lithium metal deposition, there are many advantage to using this framework: 1) the VSP-CoS2 substrate provides a high specific surface area to dissipate the ion flux and mass transfer and acts as a pre-catalyst, 2) the catalytic Co center favors the charge transfer process and preferentially binds the Li+ with the enhanced electrical fields, and 3) the VSP structure guides the metallic propagation along the nanosheet 2D orientation without the protrusive dendrites. All these features enable the VSP structure in metallic batteries with encouraging performances.
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| 26. |
- Jia, Yufei, et al.
(författare)
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Cu-based bimetallic electrocatalysts for CO2 reduction
- 2022
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Ingår i: Advanced Powder Materials. - : KeAi Communications Co.. - 2772-834X. ; 1:1
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Forskningsöversikt (refereegranskat)abstract
- The extensive consumption of fossil fuels has caused the rapid increase in the CO2 level in the atmosphere, forcing people to find a clean and efficient technology of CO2 conversion to alleviate CO2 emissions and develop value-added products. Among various CO2 conversion systems, electroreduction of CO2 to value-added chemicals is a feasible way for practical applications. Copper, the only metal that can catalyze CO2 reduction to multi-carbon products, has attracted the most attention among various catalysts. However, slow reaction kinetics, low product selectivity, as well as poor stability are the main drawbacks of single metallic Cu-based catalysts. Such issues can be addressed by introducing second metal in Cu-based catalysts. Here, we summarize the recent progress relating to the Cu-based bimetallic electrocatalysts for CO2 reduction, and discuss the composition and structure effects on the activity and selectivity of electrochemical CO2 reduction. Last, we outline the challenges and perspectives on electrocatalysts for this field. We expect that this review can provide new insights into the further development of Cu-based bimetallic electrocatalysts for CO2 reduction.
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| 27. |
- Kristan, Matej, et al.
(författare)
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The Visual Object Tracking VOT2015 challenge results
- 2015
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Ingår i: Proceedings 2015 IEEE International Conference on Computer Vision Workshops ICCVW 2015. - : IEEE. - 9780769557205 ; , s. 564-586
-
Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge 2015, VOT2015, aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 62 trackers are presented. The number of tested trackers makes VOT 2015 the largest benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the appendix. Features of the VOT2015 challenge that go beyond its VOT2014 predecessor are: (i) a new VOT2015 dataset twice as large as in VOT2014 with full annotation of targets by rotated bounding boxes and per-frame attribute, (ii) extensions of the VOT2014 evaluation methodology by introduction of a new performance measure. The dataset, the evaluation kit as well as the results are publicly available at the challenge website(1).
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| 28. |
- Li, Hanzhi, et al.
(författare)
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Effect of rock fragment cover on nutrient loss under varied rainfall intensities : A laboratory study
- 2018
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Ingår i: Hydrology Research. - : IWA Publishing. - 1998-9563 .- 0029-1277 .- 2224-7955. ; 49:2, s. 390-406
-
Tidskriftsartikel (refereegranskat)abstract
- Surface rock fragments retard overland flow discharge, reduce the runoff generation rate and soil erosion as well as nutrients loss. In Northwest China, a common method for minimizing water, soil, and nutrient losses is the use of rock fragment cover. We used lab stimulation testing to evaluate rock fragment cover efficacy for nutrient conservation. Nutrient losses were determined in both the runoff and sediments under three rain intensities (30, 60 and 90 mm·h1), four rock fragment covers (0, 10, 20 and 30%) and a slope of 10. The results showed that rock fragment cover significantly reduced the nutrient losses. Compared with the bare soil control, the rock fragment cover reduced the runoff volume and sediments by 18-38 and 11-69%, respectively, and reduced N and P losses by 9-43 and 16-70%, respectively. These results indicate that rock fragment cover is an effective method for reducing land degradation and improving local environmental conditions.
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| 29. |
- Li, Jing, et al.
(författare)
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An obligatory role for neurotensin in high-fat-diet-induced obesity
- 2016
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 533, s. 411-415
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Tidskriftsartikel (refereegranskat)abstract
- Obesity and its associated comorbidities (for example, diabetes mellitus and hepatic steatosis) contribute to approximately 2.5 million deaths annually and are among the most prevalent and challenging conditions confronting the medical profession. Neurotensin (NT; also known as NTS), a 13-amino-acid peptide predominantly localized in specialized enteroendocrine cells of the small intestine and released by fat ingestion, facilitates fatty acid translocation in rat intestine, and stimulates the growth of various cancers. The effects of NT are mediated through three known NT receptors (NTR1, 2 and 3; also known as NTSR1, 2, and NTSR3, respectively). Increased fasting plasma levels of pro-NT (a stable NT precursor fragment produced in equimolar amounts relative to NT) are associated with increased risk of diabetes, cardiovascular disease and mortality; however, a role for NT as a causative factor in these diseases is unknown. Here we show that NT-deficient mice demonstrate significantly reduced intestinal fat absorption and are protected from obesity, hepatic steatosis and insulin resistance associated with high fat consumption. We further demonstrate that NT attenuates the activation of AMP-activated protein kinase (AMPK) and stimulates fatty acid absorption in mice and in cultured intestinal cells, and that this occurs through a mechanism involving NTR1 and NTR3 (also known as sortilin). Consistent with the findings in mice, expression of NT in Drosophila midgut enteroendocrine cells results in increased lipid accumulation in the midgut, fat body, and oenocytes (specialized hepatocyte-like cells) and decreased AMPK activation. Remarkably, in humans, we show that both obese and insulin-resistant subjects have elevated plasma concentrations of pro-NT, and in longitudinal studies among non-obese subjects, high levels of pro-NT denote a doubling of the risk of developing obesity later in life. Our findings directly link NT with increased fat absorption and obesity and suggest that NT may provide a prognostic marker of future obesity and a potential target for prevention and treatment.
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| 30. |
- Li, T., et al.
(författare)
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Anisotropic, lightweight, strong, and super thermally insulating nanowood with naturally aligned nanocellulose
- 2018
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Ingår i: Science Advances. - : American Association for the Advancement of Science. - 2375-2548. ; 4:3
-
Tidskriftsartikel (refereegranskat)abstract
- There has been a growing interest in thermal management materials due to the prevailing energy challenges and unfulfilled needs for thermal insulation applications. We demonstrate the exceptional thermal management capabilities of a large-scale, hierarchal alignment of cellulose nanofibrils directly fabricated fromwood, hereafter referred to as nanowood. Nanowood exhibits anisotropic thermal properties with an extremely low thermal conductivity of 0.03W/m·K in the transverse direction (perpendicular to the nanofibrils) and approximately two times higher thermal conductivity of 0.06W/m·K in the axial direction due to the hierarchically aligned nanofibrilswithin the highly porous backbone. The anisotropy of the thermal conductivity enables efficient thermal dissipation along the axial direction, thereby preventing local overheating on the illuminated side while yielding improved thermal insulation along the backside that cannot be obtained with isotropic thermal insulators. The nanowood also shows a low emissivity of <5% over the solar spectrum with the ability to effectively reflect solar thermal energy. Moreover, the nanowood is lightweight yet strong, owing to the effective bonding between the aligned cellulose nanofibrils with a high compressive strength of 13 MPa in the axial direction and 20MPa in the transverse direction at 75% strain, which exceeds other thermal insulation materials, such as silica and polymer aerogels, Styrofoam, and wool. The excellent thermal management, abundance, biodegradability, high mechanical strength, low mass density, and manufacturing scalability of the nanowood make this material highly attractive for practical thermal insulation applications.
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| 31. |
- Lin, Hao, et al.
(författare)
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Stable and efficient hybrid Ag-In-S/ZnS@SiO2-carbon quantum dots nanocomposites for white light-emitting diodes
- 2020
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 393
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Tidskriftsartikel (refereegranskat)abstract
- As a promising energy-saving technique, the eco-friendly and low-cost solid-state white light-emitting diodes (WLEDs) based on quantum dots (QDs) have been widely studied. Herein, a WLED device prepared by core-shell structure nanocomposites based on Ag-In-S/ZnS@SiO2 quantum dots (AIS@SiO2) and carbon quantum dots (CDs) was successfully constructed. CDs were combined onto the surface of AIS@SiO2 QDs to synthesize Ag-In-S/ZnS@SiO2-Carbon quantum dots (AIS-CDs) nanocomposites with a white-light emission, which successfully overcome the quenching effect of CDs induced by conventional aggregation. The as-prepared AIS-CDs nanocomposites presented high stability and a photoluminescence quantum yield (PLQY) of 35%. Moreover, the corresponding AIS-CDs nanocomposites-based WLEDs demonstrated the color coordinate of (0.32, 0.33), which is comparable to the pure white light (0.33, 0.33); furthermore, the luminous efficiency of the as-prepared WLEDs showed 15.1 lm W-1. These results reported herein may open up a new avenue for the development of high-performance, low-cost, and environmentally-friendly WLEDs.
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| 32. |
- Lin, Jia, et al.
(författare)
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Thermochromic halide perovskite solar cells
- 2018
-
Ingår i: Nature Materials. - : Springer Science and Business Media LLC. - 1476-1122 .- 1476-4660. ; 17:3, s. 261-267
-
Tidskriftsartikel (refereegranskat)abstract
- Smart photovoltaic windows represent a promising green technology featuring tunable transparency and electrical power generation under external stimuli to control the light transmission and manage the solar energy. Here, we demonstrate a thermochromic solar cell for smart photovoltaic window applications utilizing the structural phase transitions in inorganic halide perovskite caesium lead iodide/bromide. The solar cells undergo thermally-driven, moisture-mediated reversible transitions between a transparent non-perovskite phase (81.7% visible transparency) with low power output and a deeply coloured perovskite phase (35.4% visible transparency) with high power output. The inorganic perovskites exhibit tunable colours and transparencies, a peak device efficiency above 7%, and a phase transition temperature as low as 105 degrees C. We demonstrate excellent device stability over repeated phase transition cycles without colour fade or performance degradation. The photovoltaic windows showing both photoactivity and thermochromic features represent key stepping-stones for integration with buildings, automobiles, information displays, and potentially many other technologies.
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| 33. |
- Lin, Xian Qi, et al.
(författare)
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Electromagnetically induced transparencies in a closed waveguide with high efficiency and wide frequency band
- 2012
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 101:9, s. 093502-
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Tidskriftsartikel (refereegranskat)abstract
- We propose an effective method to alleviate the conflict between large group delay and wide frequency band in electromagnetically induced transparency (EIT) design. Two kinds of electrically induced transparency (E-IT) and magnetically induced transparency (M-IT) are proposed, respectively. Then an EIT with wide transparency window is developed by combining the independent E-IT and M-IT structures. All of the transparencies are designed in a closed waveguide system, and high efficiency is obtained at the same time. One sample is fabricated and the bandwidth is increased to more than 3 times without decrease of the group delay and increase of the size.
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| 34. |
- Liu, Yong-feng, et al.
(författare)
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Highly Soluble CsPbBr3 Perovskite Quantum Dots for Solution-Processed Light-Emission Devices
- 2021
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Ingår i: ACS Applied Nano Materials. - : American Chemical Society (ACS). - 2574-0970. ; , s. 1162-1174
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Tidskriftsartikel (refereegranskat)abstract
- We report on the synthesis of CsPbBr3 perovskite quantum dots (PeQDs) with a high solubility of 75 g/L in toluene and a good film-forming property, as enabled by a dense layer of didodecyldimethylammonium bromide and octanoic acid surface ligands. The crystalline and monodisperse PeQDs feature a cubic-like shape, with an edge length of 10.1 nm, and a high photoluminescence quantum yield of greater than 90% in toluene solution and 36% as a thin film. We find that the PeQDs are n-type doped following the synthesis but also that they can be p-type and additionally n-type doped by in situ electrochemistry. These combined properties render the PeQDs interesting for the emitter in solution-processed light-emitting electrochemical cells (LECs), and we report a PeQD-LEC with air-stabile electrodes that emits with a narrow emission spectrum (λpeak = 514 nm, full width at half-maximum = 24 nm) and a luminance of 250 cd/m2 at 4 V and a luminance of 1090 cd/m2 at 6.8 V. To reach this performance, it was critical to include a thin solution-processed layer comprising p-type poly(vinyl carbazole) and a tetrahexylammonium tetrafluoroborate ionic liquid between the PeQD emission layer and the anode in order to compensate for the as-synthesized n-type doping of the PeQDs.
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| 35. |
- Luo, Yifei, et al.
(författare)
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Technology Roadmap for Flexible Sensors
- 2023
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Ingår i: ACS Nano. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 17:6, s. 5211-5295
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Forskningsöversikt (refereegranskat)abstract
- Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity.
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| 36. |
- Meyer, Peter A., et al.
(författare)
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Data publication with the structural biology data grid supports live analysis
- 2016
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- Access to experimental X-ray diffraction image data is fundamental for validation and reproduction of macromolecular models and indispensable for development of structural biology processing methods. Here, we established a diffraction data publication and dissemination system, Structural Biology Data Grid (SBDG; data. sbgrid. org), to preserve primary experimental data sets that support scientific publications. Data sets are accessible to researchers through a community driven data grid, which facilitates global data access. Our analysis of a pilot collection of crystallographic data sets demonstrates that the information archived by SBDG is sufficient to reprocess data to statistics that meet or exceed the quality of the original published structures. SBDG has extended its services to the entire community and is used to develop support for other types of biomedical data sets. It is anticipated that access to the experimental data sets will enhance the paradigm shift in the community towards a much more dynamic body of continuously improving data analysis.
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| 37. |
- Moser, Debra K., et al.
(författare)
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Identification of symptom clusters among patients with heart failure: An international observational study
- 2014
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Ingår i: International Journal of Nursing Studies. - : Elsevier. - 0020-7489 .- 1873-491X. ; 51:10, s. 1366-1372
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Tidskriftsartikel (refereegranskat)abstract
- Background: Virtually all patients with heart failure experience multiple symptoms simultaneously, yet clinicians and researchers usually consider symptoms in isolation. Recognizing and responding early to escalating symptoms is essential to preventing hospitalizations in heart failure, yet patients have considerable difficulty recognizing symptoms. Identification of symptom clusters could improve symptom recognition, but cultural differences may be present that must be considered. Objectives: To identify and compare symptom clusters in heart failure patients from the United States, Europe and Asia. Design: Cross-sectional, observational study. Settings: In- and out-patient settings in three regions of the world: Asia (i.e., China and Taiwan); Europe (i.e., the Netherlands and Sweden); and the United States. Participants: A total of 720 patients with confirmed heart failure. Propensity scoring using New York Heart Association Classification was used to match participants from each of the three regions. Methods: Symptoms were identified using the Minnesota Living with Heart Failure Questionnaire. To identify symptom clusters we used cluster analysis with the hierarchical cluster agglomerative approach. We used the Euclidean distance to measure the similarity of variables. Proximity between groups of variables was measured using Wards method. The resulting clusters were displayed with dendrograms, which show the proximity of variables to each other on the basis of semi-partial R-squared scores. Results: There was a core group of symptoms that formed two comparable clusters across the countries. Dyspnea, difficulty in walking or climbing, fatigue/increased need to rest, and fatigue/low energy were grouped into a cluster, which was labeled as a physical capacity symptom cluster. Worrying, feeling depressed, and cognitive problems were grouped into a cluster, which was labeled as an emotional/cognitive symptom cluster. The symptoms of edema and trouble sleeping were variable among the countries and fell into different clusters. Conclusion: Despite the diversity in cultures studied, we found that symptoms clustered similarly among the cultural groups. Identification of similar symptoms clusters among patients with heart failure may improve symptom recognition in both patients and healthcare providers.
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| 38. |
- Ni, Yueran, et al.
(författare)
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Microporous core-shell Co-11(HPO3)(8)(OH)(6)/Co-11(PO3)(8)O-6 nanowires for highly efficient electrocatalytic oxygen evolution reaction
- 2019
-
Ingår i: Applied Catalysis B. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 259
-
Tidskriftsartikel (refereegranskat)abstract
- Exploring high-efficient oxygen evolution reaction (OER) catalysts is critical for producing clean H-2 fuel through water splitting. Co and P involved Co-Pi and cobalt phosphide OER catalysts attracted tremendous attention, while limited report on cobalt phosphite as an OER catalyst. Herein, a novel cobalt phosphite nanowires with microporous 1D channel have been succsessfully discovered with remarkable catalytic performance of a low overpotential of (similar to)340 mV and Tafel slope of 60 mV dec(-1) at 10 mA cm(-2) at pH 14. Through comprehensive structural characterization, the effective species has been clearly illustrated to be the in-situ formed heterostructural Co-11(HPO3)(8)(OH)(6)/Co-11(PO3)(8)O-6 core-shell structure nanowires. This work fills the gap for exploring high efficient cobalt phosphites OER catalysts under akaline condition and paves the way for exploring novel high efficiency waster splitting catalysts.
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| 39. |
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| 40. |
- Shang, Yu, et al.
(författare)
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Pyrrolic N or pyridinic N : The active center of N-doped carbon for CO2 reduction
- 2022
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Ingår i: Cuihuà xuébào. - : Elsevier BV. - 0253-9837 .- 1872-2067. ; 43:9, s. 2405-2413
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Tidskriftsartikel (refereegranskat)abstract
- Pyridinic N is widely regarded as the active center while pyrrolic N has low-activity in metal-free N-doped carbon for electrocatalytic CO2 reduction reaction (CO2RR) to CO, but this viewpoint remains open to question. In this study, through density functional theoretical calculations, we first illustrate that the intrinsic activity of pyrrolic N is high enough for effectively catalyzing CO2RR, however, due to the interplay with the neighboring pyridinic N sites, the activity of pyrrolic N is dramatically suppressed. Then, experimentally, metal-free N-doped carbon spheres (NCS) electrocatalysts without significant pyridinic N content are prepared for CO2RR. The pyrrolic N in NCS shows a direct-positive correlation with the performance for CO2RR, representing the active center with high activity. The optimum NCS could produce syngas with a wide range of CO/H-2 ratio (0.09 to 12) in CO2RR depending on the applied potential, meanwhile, the best selectivity of 71% for CO can be obtained. Intentionally adding a small amount of pyridinic N to the optimum NCS dramatically decreases the activity for CO2RR, further verifying the suppressed activity of pyrrolic N sites by the neighboring pyridinic N sites. This work reveals the interaction between a variety of N species in N-doped carbon, and the potential of pyrrolic N as the new type of active site for electrocatalysts, which can improve our understanding of the electrocatalysis mechanism and be helpful for the rational design of high-efficient electrocatalysts.
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| 41. |
- Shao, Xue-Feng, et al.
(författare)
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Hydroxyl group functionalized graphene oxide nanosheets as additive for improved erythritol latent heat storage performance : A comprehensive evaluation on the benefits and challenges
- 2020
-
Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 215
-
Tidskriftsartikel (refereegranskat)abstract
- Graphene oxide (GO) nanosheets were employed as the additive to make composites of erythritol, a promising medium-temperature PCM candidate. GO nanosheets modified with hydroxyl groups were applied to improve the dispersion stability of the composites. A systematic characterization on the latent heat storage performance was performed for both pure and composite erythritol, in order to identify the benefits and challenges of the composites. It was found that the thermal conductivity is increased by nearly twice and the degree of supercooling was lowered from ~64 °C to ~48 °C at the loading of 1.0 wt% GO nanosheets (the maximum loading tested). The addition of GO nanosheets also leads to an increase of the retrievable latent heat during crystallization, from ~187 kJ/kg to ~225 kJ/kg at the same loading, by increasing the crystallinity. However, the introduction of GO nanosheets can also lead to a rise in the dynamic viscosity of erythritol. As a result, the crystallization rate is slowed down and accordingly, the duration of crystallization becomes 62% longer when the loading reaches 1.0 wt%. In addition, favorable dispersion stability of the erythritol composites is observed, and their melting point (~117 °C) remains almost unchanged during 50 melting-crystallization cycles. Functionalized GO nanosheets have been shown to be an efficient additive for improving the performance of erythritol, but a trade-off analysis on the loading would be required to achieve the best overall performance.
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| 42. |
- Shieh, Jia-Min, et al.
(författare)
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Enhanced photoresponse of a metal-oxide-semiconductor photodetector with silicon nanocrystals embedded in the oxide layer
- 2007
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Ingår i: Applied Physics Letters. - : American Institute of Physics. - 0003-6951 .- 1077-3118. ; 90:5
-
Tidskriftsartikel (refereegranskat)abstract
- The authors report a two-terminal metal-oxide-semiconductor photodetector for which light is absorbed in a capping layer of silicon nanocrystals embedded in a mesoporous silica matrix on p-type silicon substrates. Operated at reverse bias, enhanced photoresponse from 300 to 700 nm was observed. The highest optoelectronic conversion efficiency is as high as 200%. The enhancements were explained by a transistorlike mechanism, in which the inversion layer acts as the emitter and trapped positive charges in the mesoporous dielectric layer assist carrier injection from the inversion layer to the contact, such that the primary photocurrent could be amplified.
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| 43. |
- Wang, Anci, et al.
(författare)
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Principle and performance optimization analysis of a frost-free control for electric vehicle heat pumps
- 2023
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311. ; 226
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Tidskriftsartikel (refereegranskat)abstract
- To avoid the attenuation of the electric vehicle driving range caused by the performance degradation of the heat pump during frost, a frost-free control strategy was developed which enables frost-free operation without adding any additional dehumidifying and drying components. Simulation analyses of the frost-free control principle and performance characteristics are carried out. Thermodynamic and response characteristics of evaporation temperature to valve openings of different heat pumps are compared. The results show that excessive pressure drops in evaporators severely hinder the realization of frost-free operation. Then, the effect of evaporator designs on frost-free operation is further investigated. A new comprehensive evaluation parameter (η) that can unify pressure drop and heat transfer is proposed. When η is between 0 and −2, the heat exchanger meets the requirements of frost-free control. In addition, the upper humidity range for frost-free operation at different temperatures is calibrated. When the ambient temperature is 0/-5/-10/-15/-25 °C, the corresponding maximum humidity that can achieve frost-free operation is 87/86/85/84/82 %, respectively. In low temperature and high humidity regions, the frost-free operation can be guaranteed by increasing the evaporator airflow volume rate and reducing the supply air temperature.
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| 44. |
- Wang, Zhaoming, et al.
(författare)
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Imputation and subset-based association analysis across different cancer types identifies multiple independent risk loci in the TERT-CLPTM1L region on chromosome 5p15.33
- 2014
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 23:24, s. 6616-6633
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants on 5p15.33. Our results provide strong support for extensive pleiotropy across this region of 5p15.33, to an extent not previously observed in other cancer susceptibility loci.
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| 45. |
- Wheeler, Eleanor, et al.
(författare)
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Impact of common genetic determinants of Hemoglobin A1c on type 2 diabetes risk and diagnosis in ancestrally diverse populations : A transethnic genome-wide meta-analysis
- 2017
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Ingår i: PLoS Medicine. - : PUBLIC LIBRARY SCIENCE. - 1549-1277 .- 1549-1676. ; 14:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Glycated hemoglobin (HbA1c) is used to diagnose type 2 diabetes (T2D) and assess glycemic control in patients with diabetes. Previous genome-wide association studies (GWAS) have identified 18 HbA1c-associated genetic variants. These variants proved to be classifiable by their likely biological action as erythrocytic (also associated with erythrocyte traits) or glycemic (associated with other glucose-related traits). In this study, we tested the hypotheses that, in a very large scale GWAS, we would identify more genetic variants associated with HbA1c and that HbA1c variants implicated in erythrocytic biology would affect the diagnostic accuracy of HbA1c. We therefore expanded the number of HbA1c-associated loci and tested the effect of genetic risk-scores comprised of erythrocytic or glycemic variants on incident diabetes prediction and on prevalent diabetes screening performance. Throughout this multiancestry study, we kept a focus on interancestry differences in HbA1c genetics performance that might influence race-ancestry differences in health outcomes.Methods & findings: Using genome-wide association meta-analyses in up to 159,940 individuals from 82 cohorts of European, African, East Asian, and South Asian ancestry, we identified 60 common genetic variants associated with HbA1c. We classified variants as implicated in glycemic, erythrocytic, or unclassified biology and tested whether additive genetic scores of erythrocytic variants (GS-E) or glycemic variants (GS-G) were associated with higher T2D incidence in multiethnic longitudinal cohorts (N = 33,241). Nineteen glycemic and 22 erythrocytic variants were associated with HbA1c at genome-wide significance. GS-G was associated with higher T2D risk (incidence OR = 1.05, 95% CI 1.04-1.06, per HbA1c-raising allele, p = 3 x 10-29); whereas GS-E was not (OR = 1.00, 95% CI 0.99-1.01, p = 0.60). In Europeans and Asians, erythrocytic variants in aggregate had only modest effects on the diagnostic accuracy of HbA1c. Yet, in African Americans, the X-linked G6PD G202A variant (T-allele frequency 11%) was associated with an absolute decrease in HbA1c of 0.81%-units (95% CI 0.66-0.96) per allele in hemizygous men, and 0.68%-units (95% CI 0.38-0.97) in homozygous women. The G6PD variant may cause approximately 2% (N = 0.65 million, 95% CI0.55-0.74) of African American adults with T2Dto remain undiagnosed when screened with HbA1c. Limitations include the smaller sample sizes for non-European ancestries and the inability to classify approximately one-third of the variants. Further studies in large multiethnic cohorts with HbA1c, glycemic, and erythrocytic traits are required to better determine the biological action of the unclassified variants.Conclusions: As G6PD deficiency can be clinically silent until illness strikes, we recommend investigation of the possible benefits of screening for the G6PD genotype along with using HbA1c to diagnose T2D in populations of African ancestry or groups where G6PD deficiency is common. Screening with direct glucose measurements, or genetically-informed HbA1c diagnostic thresholds in people with G6PD deficiency, may be required to avoid missed or delayed diagnoses.
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| 46. |
- Xie, Haibing, et al.
(författare)
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Decoupling the effects of defects on efficiency and stability through phosphonates in stable halide perovskite solar cells
- 2021
-
Ingår i: Joule. - : CELL PRESS. - 2542-4351. ; 5:5, s. 1246-1266
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Tidskriftsartikel (refereegranskat)abstract
- Understanding defects is of paramount importance for the development of stable halide perovskite solar cells (PSCs). However, isolating their distinctive effects on device efficiency and stability is currently a challenge. We report that adding the organic molecule 3-phosphonopropionic acid (H3pp) to the halide perovskite results in unchanged overall optoelectronic performance while having a tremendous effect on device stability. We obtained PSCs with similar to 21% efficiency that retain similar to 100% of the initial efficiency after 1,000 h at the maximum power point under simulated AM1.5G illumination. The strong interaction between the perovskite and the H3pp molecule through two types of hydrogen bonds (H center dot center dot center dot I and O center dot center dot center dot H) leads to shallow point defect passivation that has a significant effect on device stability but not on the non-radiative recombination and device efficiency. We expect that our work will have important implications for the current understanding and advancement of operational PSCs.
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| 47. |
- Xu, An, et al.
(författare)
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Rewired m6A epitranscriptomic networks link mutant p53 to neoplastic transformation
- 2023
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- N6-methyladenosine (m6A), one of the most prevalent mRNA modifications in eukaryotes, plays a critical role in modulating both biological and pathological processes. However, it is unknown whether mutant p53 neomorphic oncogenic functions exploit dysregulation of m6A epitranscriptomic networks. Here, we investigate Li-Fraumeni syndrome (LFS)-associated neoplastic transformation driven by mutant p53 in iPSC-derived astrocytes, the cell-of-origin of gliomas. We find that mutant p53 but not wild-type (WT) p53 physically interacts with SVIL to recruit the H3K4me3 methyltransferase MLL1 to activate the expression of m6A reader YTHDF2, culminating in an oncogenic phenotype. Aberrant YTHDF2 upregulation markedly hampers expression of multiple m6A-marked tumor-suppressing transcripts, including CDKN2B and SPOCK2, and induces oncogenic reprogramming. Mutant p53 neoplastic behaviors are significantly impaired by genetic depletion of YTHDF2 or by pharmacological inhibition using MLL1 complex inhibitors. Our study reveals how mutant p53 hijacks epigenetic and epitranscriptomic machinery to initiate gliomagenesis and suggests potential treatment strategies for LFS gliomas.
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| 48. |
- Xu, Shuang Feng, et al.
(författare)
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Lactoferrin ameliorates dopaminergic neurodegeneration and motor deficits in MPTP-treated mice
- 2019
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Ingår i: Redox Biology. - : Elsevier BV. - 2213-2317. ; 21
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Tidskriftsartikel (refereegranskat)abstract
- Brain iron accumulation is common in patients with Parkinson's disease (PD). Iron chelators have been investigated for their ability to prevent neurodegenerative diseases with features of iron overload. Given the non-trivial side effects of classical iron chelators, lactoferrin (Lf), a multifunctional iron-binding globular glycoprotein, was screened to identify novel neuroprotective pathways against dopaminergic neuronal impairment. We found that Lf substantially ameliorated PD-like motor dysfunction in the subacute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. We further showed that Lf could alleviate MPTP-triggered apoptosis of DA neurons, neuroinflammation, and histological alterations. As expected, we also found that Lf suppressed MPTP-induced excessive iron accumulation and the upregulation of divalent metal transporter (DMT1) and transferrin receptor (TFR), which is the main intracellular iron regulation protein, and subsequently improved the activity of several antioxidant enzymes. We probed further and determined that the neuroprotection provided by Lf was involved in the upregulated levels of brain-derived neurotrophic factor (BDNF), hypoxia-inducible factor 1α (HIF-1α) and its downstream protein, accompanied by the activation of extracellular regulated protein kinases (ERK) and cAMP response element binding protein (CREB), as well as decreased phosphorylation of c-Jun N-terminal kinase (JNK) and mitogen activated protein kinase (MAPK)/P38 kinase in vitro and in vivo. Our findings suggest that Lf may be an alternative safe drug in ameliorating MPTP-induced brain abnormalities and movement disorder.
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| 49. |
- Xue, Ru, et al.
(författare)
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Variations of methane fluxes and methane microbial community composition with soil depth in the riparian buffer zone of a sponge city park
- 2023
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Ingår i: Journal of Environmental Management. - : Elsevier. - 0301-4797 .- 1095-8630. ; 339
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Tidskriftsartikel (refereegranskat)abstract
- Riparian buffers benefit both natural and man-made ecosystems by preventing soil erosion, retaining soil nu-trients, and filtering pollutants. Nevertheless, the relationship between vertical methane fluxes, soil carbon, and methane microbial communities in riparian buffers remains unclear. This study examined vertical methane fluxes, soil carbon, and methane microbial communities in three different soil depths (0-5 cm, 5-10 cm, and 10-15 cm) within a riparian buffer of a Sponge City Park for one year. Structural equation model (SEM) results demonstrated that vertical methane fluxes varied with soil depths (lambda =-0.37) and were primarily regulated by methanogenic community structure (lambda = 0.78). Notably, mathematical regression results proposed that mcrA/ pmoA ratio (R2 = 0.8) and methanogenic alpha diversity/methanotrophic alpha diversity ratio (R2 = 0.8) could serve as valid predictors of vertical variation in methane fluxes in the riparian buffer of urban river. These findings suggest that vertical variation of methane fluxes in riparian buffer soils is mainly influenced by carbon inputs and methane microbial abundance and community diversity. The study's results quantitatively the relationship between methane fluxes in riparian buffer soils and abiotic and biotic factors in the vertical di-rection, therefore contributing to the further development of mathematical models of soil methane emissions.
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| 50. |
- Zhang, Juankun, et al.
(författare)
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A Label Free Electrochemical Nanobiosensor Study
- 2009
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Ingår i: Analytical Letters. - : Taylor and Francis. - 0003-2719 .- 1532-236X. ; 42:17, s. 2905-2913
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Tidskriftsartikel (refereegranskat)abstract
- Nano-porous silicon (PS) is an attractive material for incorporation into biosensors, because it has a large surface area combined with the ability to generate both optical and electrical signals. In this paper, we describe a label-free nanobiosensor for bovine serum albumin (BSA). Nano-porous silicon produced in our laboratory was functionalized prior to immobilization of anti-BSA antibody on the surface. Reaction with BSA in phosphate buffered saline (PBS) buffer resulted in an impedance change which was inversely proportional to the concentration of the analyte. The system PBS buffer/antigen-antibody/PS constitutes an electrolyte-insulator-semiconductor (EIS) structure, thus furnishing an impedance EIS nanobiosensor. The linear range of the sensor was 0-0.27mgmL-1 and the sensitivity was less than 10 mu g mL-1.
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