| 1. |
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| 2. |
- Jin, Ying-Hui, et al.
(författare)
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Chemoprophylaxis, diagnosis, treatments, and discharge management of COVID-19 : An evidence-based clinical practice guideline (updated version)
- 2020
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Ingår i: Military Medical Research. - : Springer Science and Business Media LLC. - 2054-9369. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of a rapidly spreading illness, coronavirus disease 2019 (COVID-19), affecting more than seventeen million people around the world. Diagnosis and treatment guidelines for clinicians caring for patients are needed. In the early stage, we have issued "A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)"; now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based guideline. We formed a working group of clinical experts and methodologists. The steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas: chemoprophylaxis, diagnosis, treatments, and discharge management. We searched the literature for direct evidence on the management of COVID-19, and assessed its certainty generated recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Recommendations were either strong or weak, or in the form of ungraded consensus-based statement. Finally, we issued 34 statements. Among them, 6 were strong recommendations for, 14 were weak recommendations for, 3 were weak recommendations against and 11 were ungraded consensus-based statement. They covered topics of chemoprophylaxis (including agents and Traditional Chinese Medicine (TCM) agents), diagnosis (including clinical manifestations, reverse transcription-polymerase chain reaction (RT-PCR), respiratory tract specimens, IgM and IgG antibody tests, chest computed tomography, chest x-ray, and CT features of asymptomatic infections), treatments (including lopinavir-ritonavir, umifenovir, favipiravir, interferon, remdesivir, combination of antiviral drugs, hydroxychloroquine/chloroquine, interleukin-6 inhibitors, interleukin-1 inhibitors, glucocorticoid, qingfei paidu decoction, lianhua qingwen granules/capsules, convalescent plasma, lung transplantation, invasive or noninvasive ventilation, and extracorporeal membrane oxygenation (ECMO)), and discharge management (including discharge criteria and management plan in patients whose RT-PCR retesting shows SARS-CoV-2 positive after discharge). We also created two figures of these recommendations for the implementation purpose. We hope these recommendations can help support healthcare workers caring for COVID-19 patients.
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| 3. |
- 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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| 4. |
- Sampson, Joshua N., et al.
(författare)
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Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for 13 Cancer Types
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 107:12
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Tidskriftsartikel (refereegranskat)abstract
- Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, h(l)(2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (rho = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (rho = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (rho = 0.51, SE = 0.18), and bladder and lung (rho = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.
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| 5. |
- Wang, Fang, et al.
(författare)
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Emerging contaminants: A One Health perspective
- 2024
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Ingår i: Innovation. - 2666-6758. ; 5
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Forskningsöversikt (refereegranskat)abstract
- Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both people and the planet. In response, global initiatives are focusing on risk assessment and regulation of emerging contaminants, as demonstrated by the ongoing efforts to establish the UN's Intergovernmental Science-Policy Panel on Chemicals, Waste, and Pollution Prevention. This review identifies the sources and impacts of emerging contaminants on planetary health, emphasizing the importance of adopting a One Health approach. Strategies for monitoring and addressing these pollutants are discussed, underscoring the need for robust and socially equitable environmental policies at both regional and international levels. Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.
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| 6. |
- Fu, Kai, 1981-
(författare)
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Growth Dynamics of Semiconductor Nanostructures by MOCVD
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Semiconductors and related low-dimensional nanostructures are extremely important in the modern world. They have been extensively studied and applied in industry/military areas such as ultraviolet optoelectronics, light emitting diodes, quantum-dot photodetectors and lasers. The knowledge of growth dynamics of semiconductor nanostructures by metalorganic chemical vapour deposition (MOCVD) is very important then. MOCVD, which is widely applied in industry, is a kind of chemical vapour deposition method of epitaxial growth for compound semiconductors. In this method, one or several of the precursors are metalorganics which contain the required elements for the deposit materials. Theoretical studies of growth mechanism by MOCVD from a realistic reactor dimension down to atomic dimensions can give fundamental guidelines to the experiment, optimize the growth conditions and improve the quality of the semiconductor-nanostructure-based devices. Two main types of study methods are applied in the present thesis in order to understand the growth dynamics of semiconductor nanostructures at the atomic level: (1) Kinetic Monte Carlo method which was adopted to simulate film growths such as diamond, Si, GaAs and InP using the chemical vapor deposition method; (2) Computational fluid dynamics method to study the distribution of species and temperature in the reactor dimension. The strain energy is introduced by short-range valence-force-field method in order to study the growth process of the hetero epitaxy. The Monte Carlo studies show that the GaN film grows on GaN substrate in a two-dimensional step mode because there is no strain over the surface during homoepitaxial growth. However, the growth of self-assembled GaSb quantum dots (QDs) on GaAs substrate follows strain-induced Stranski-Krastanov mode. The formation of GaSb nanostructures such as nanostrips and nanorings could be determined by the geometries of the initial seeds on the surface. Furthermore, the growth rate and aspect ratio of the GaSb QD are largely determined by the strain field distribution on the growth surface.
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| 7. |
- Fu, Kai, et al.
(författare)
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Kinetic Monte Carlo study of metal organic chemical vapor deposition growth dynamics of GaN thin film at microscopic level
- 2008
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 103:10, s. 103524-
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Tidskriftsartikel (refereegranskat)abstract
- Group III nitrides, especially gallium nitride (GaN), have many applications. The materials are usually grown by metal organic chemical vapor deposition (MOCVD) technology. By combining the computational fluid dynamics and kinetic Monte Carlo method, we present a multiscale modeling of fluid dynamics, thermodynamics, and molecular dynamics to study the chemical and physical growth process of GaN in a standard MOCVD reactor, which shows a general agreement with experimental results. The theoretical model thus provides us with a fundamental guideline for optimizing GaN MOCVD growth at the microscopic level.
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| 8. |
- Fu, Kai, et al.
(författare)
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Kinetic Monte Carlo study of metal organic chemical vapor deposition growth mechanism of GaSb quantum dots
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 93:101906
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Tidskriftsartikel (refereegranskat)abstract
- The growth dynamics of self-assembled GaSb quantum dots (QDs) on GaAs substrate in the strain-induced Stranski-Krastanov mode was investigated using kinetic Monte Carlo method. The strain induced by the lattice mismatch between the epitaxial material and the substrate was shown to be directly responsible for the QD formation and the transition of growth mode from two dimensional to three dimensional.
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| 9. |
- Fu, Kai, et al.
(författare)
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Strain-induced Stranski-Krastanov three dimensional growth mode of GaSb quantum dot on GaAs substrate
- 2009
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 94:181913
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Tidskriftsartikel (refereegranskat)abstract
- The growth dynamics of self-assembled GaSb quantum dots (QDs) on GaAs substrate was investigated using kinetic Monte Carlo method. The strain induced by the lattice mismatch between the epitaxial material and the substrate was shown to be directly responsible for the three-dimensional QD formation. Different geometries of the initial seeds on the surface which are equally favorable from an energy point of view can result in different GaSb nanostructures (nanostrips and nanoring).
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| 10. |
- Hou, Ying, et al.
(författare)
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Carrier wave-packet transport under the influence of charged quantum dot in small-area resonant tunneling diodes
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 93:13, s. 132108-
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Tidskriftsartikel (refereegranskat)abstract
- It was shown experimentally that charging InAs quantum dots (QDs) embedded in a small-area GaAs/AlAs double-barrier resonant tunneling diode (RTD) effectively modified the carrier transport properties of the RTD. By adopting and comparing the one-dimensional plane-wave and three-dimensional (3D) wave-packet transport theories we show that the electron transports in the QDRTD device are in the form of 3D wave packets, which are strongly affected by the 3D long-range Coulomb potential induced by charged InAs QDs. This explains well experimental data and indicates that the 3D wave-packet transport model is more appropriate for the QDRTD device.
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| 11. |
- Hou, Ying, et al.
(författare)
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Effects of series and parallel resistances on the current-voltage characteristics of small-area air-bridge resonant tunneling diode
- 2008
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 104:7
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Tidskriftsartikel (refereegranskat)abstract
- We have studied experimentally and theoretically the effects of series and parallel resistances on the current-voltage (I-V) characteristics of the resonant tunneling diode (RTD) in the format of a small-area freestanding air bridge. It has been shown by standard quantum mechanical considerations that the I-V characteristics consists of a simple resonant current peak (without bistability) and the voltage at the current peak is quite low, whereas experiments show not only a much high current-peak voltage, but also the bistability. Furthermore, experimental peak-to-valley ratio is in general quite low. By analyzing material and device structures, it has been demonstrated that the series resistance in the RTD contacts shifts the peak in current to higher voltage, it also creates the experimentally observed bistability effect in the region of the tunneling resonance. The parallel resistance induces a leakage current and reduces the peak-to-valley ratio. We have further performed similar analyses to many RTD structures reported in the literature and the conclusions remain the same.
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| 12. |
- Hou, Ying
(författare)
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Experimental and theoretical study of quantum dot resonant tunneling diodes for single photon detection
- 2008
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Single photon detection has a broad application in the medical, telecommunication, as well as in infrared imaging fields. In this thesis I present my work in studying quantum dot (QD) resonant tunneling diodes (RTD) for single photon detection. The device was processed in the form of a free-standing small-area air bridge. A detailed series of experimental and theoretical characterizations have been performed to understand the electrical properties of the RTDs (without embedding any QDs) and QD-embedded RTDs (QDRTDs). It has been shown that external series and parallel resistances shift the resonant current peak to higher voltage, create the bistability effect observed in I-V characteristics, and reduce the peak-to-valley ratio. For the QDRTD device, three-dimensional wave packet carrier transport simulations show strong influence of the long-range Coulomb potential induced by the hole captured by the embedded InAs QDs, thus demonstrating the fundamental principle of single photon detection. Two works are planned for the continuation of the graduate study after Lic examination. The optical response of the QDRTD will be experimentally and theoretically characterized in order to optimize the quantum efficiency for single photon detection. I will then concentrate on processing a one-dimensional photodetector array aiming at practical biotechnology applications.
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| 13. |
- Li, N., et al.
(författare)
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Dark currents of GaAs/AlGaAs quantum-well infrared photodetectors
- 2007
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Ingår i: Applied Physics A. - : Springer Science and Business Media LLC. - 0947-8396 .- 1432-0630. ; 89:3, s. 701-705
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Tidskriftsartikel (refereegranskat)abstract
- We study the dark current of the GaAs/AlGaAs quantum-well infrared photodetector (QWIP) by assuming a drift-diffusion carrier transport in the barriers where the electric fields are obtained by the current continuity condition and the self-consistent energy band structure. It has been shown that due to the current continuity condition, the dark currents across the QWIP devices are determined by the thermionic emission from the emitter to the multiple quantum well (MQW) region. The self-consistent calculation of the Schrodinger and Poisson equations shows a weak electric field in the barrier region connecting to the emitter (much smaller than the average field across the QWIP at low bias) due to the accumulation of carriers in the triangle quantum well formed at the emitter-MQW interface, which results in a very small dark current at low bias. The numerical results explain well our experimental observation.
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| 14. |
- Li, Xinyi, et al.
(författare)
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Emerging Data Processing Methods for Single-Entity Electrochemistry
- 2024
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Ingår i: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION. - 1433-7851 .- 1521-3773. ; 63:17
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Forskningsöversikt (refereegranskat)abstract
- Single-entity electrochemistry is a powerful tool that enables the study of electrochemical processes at interfaces and provides insights into the intrinsic chemical and structural heterogeneities of individual entities. Signal processing is a critical aspect of single-entity electrochemical measurements and can be used for data recognition, classification, and interpretation. In this review, we summarize the recent five-year advances in signal processing techniques for single-entity electrochemistry and highlight their importance in obtaining high-quality data and extracting effective features from electrochemical signals, which are generally applicable in single-entity electrochemistry. Moreover, we shed light on electrochemical noise analysis to obtain single-molecule frequency fingerprint spectra that can provide rich information about the ion networks at the interface. By incorporating advanced data analysis tools and artificial intelligence algorithms, single-entity electrochemical measurements would revolutionize the field of single-entity analysis, leading to new fundamental discoveries. This Minireview summarizes the latest advances in data processing techniques for single-entity electrochemistry towards achieving automation, real-time monitoring, increased sensitivity, as well as improved temporal and current resolution. image
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| 15. |
- Liu, Hui Rong, et al.
(författare)
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Relationship of myocardial remodeling to the genesis of serum autoantibodies to cardiac beta(1)-adrenoceptors and muscarinic type 2 acetylcholine receptors in rats.
- 2002
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Ingår i: Journal of the American College of Cardiology. - 0735-1097. ; 39:11, s. 1866-73
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: We sought to investigate the mechanism responsible for the occurrence of anticardiac receptor autoantibodies. BACKGROUND: Increasing evidence suggests the involvement of autoimmune mechanisms in the pathogenesis of a number of cardiovascular diseases. Among them, the biologic, functional and pathogenic properties of anticardiac receptor antibodies have been extensively investigated. However, the mechanism responsible for the occurrence of anticardiac receptor autoantibodies remains poorly understood. METHODS: Two rat models (aortic banding [AB] and adriamycin [ADR] groups) were constructed. Determination of cardiac function and morphology and T-lymphocyte subtypes, enzyme-linked immunosorbent assay and cardiomyocyte cultures were performed. RESULTS: It was shown, in the AB and ADR groups, that the frequency and titer of autoantibodies to beta(1) and muscarinic type 2 receptors were increased when myocardial remodeling occurred, as evidenced by significant cardiac morphologic changes, deposition of collagen and obvious functional impairment. This suggests that cardiac remodeling itself, in two disparate models of heart failure and cardiomyopathy, was able to trigger the genesis of anticardiac receptor autoantibodies. These autoantibodies have biologic effects similar to those seen in human autoantibodies. They have also shown a characteristic self-growth, as well as a time-course decline, suggesting that a negative finding of anticardiac receptor autoantibodies in sera of patients with heart disease does not necessarily imply that there is no autoimmune reaction involved in the pathogenesis. CONCLUSIONS: Our results demonstrated that myocardial damage was able to trigger the occurrence of an autoimmune reaction, resulting in the genesis of anticardiac receptor autoantibodies with properties similar to those seen in patients with idiopathic dilated cardiomyopathy.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Qin, Hai-Yan, et al.
(författare)
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Observation of Bunched Blinking from Individual CdSe/CdS and CdSe/ZnS Colloidal Quantum Dots
- 2012
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 116:23, s. 12786-12790
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Tidskriftsartikel (refereegranskat)abstract
- Blinking and time correlation between fluorescences of neighboring negatively charged CdSe/CdS and CdSe/ZnS colloidal quantum dots have been studied experimentally. A tendency of synchronous blinking, that is, a bunching effect, is clearly observed from two neighboring QDs with a spatial separation up to 1.1 mu m. We believe that our observations will help to better understand the mechanisms for the blinking.
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| 20. |
- Shang, Xiangjun, et al.
(författare)
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Effect of tunable dot charging on photoresponse spectra of GaAs p-i-n diode with InAs quantum dots
- 2015
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Ingår i: Journal of Applied Physics. - Melville, NY : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 118:24
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Tidskriftsartikel (refereegranskat)abstract
- Quantum dot (QD)-embedded photodiodes have demonstrated great potential for use as detectors. A modulation of QD charging opens intriguing possibilities for adaptive sensing with bias-tunable detector characteristics. Here, we report on a p-i-n GaAs photodiode with InAs QDs whose charging is tunable due to unintentional Be diffusion and trap-assisted tunneling of holes, from bias-and temperature (T)-dependent photocurrent spectroscopy. For the sub-bandgap spectra, the T-dependent relative intensities "QD-s/WL" and "WL/GaAs" (WL: wetting layer) indicate dominant tunneling under -0.9V (trap-assisted tunneling from the top QDs) and dominant thermal escape under -0.2 similar to 0.5V (from the bottom QDs since the top ones are charged and inactive for optical absorption) from the QD s-state, dominant tunneling from WL, and enhanced QD charging at >190K (related to trap level ionization). For the above-bandgap spectra, the degradation of the spectral profile (especially near the GaAs bandedge) as the bias and T tune (especially under -0.2 similar to 0.2V and at >190 K) can be explained well by the enhanced photoelectron capture in QDs with tunable charging. The dominant spectral profile with no degradation under 0.5V is due to a saturated electron capture in charged QDs (i.e., charging neutralization). QD level simulation and schematic bandstructures can help one understand these effects.
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| 21. |
- Song, Yanling, et al.
(författare)
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Growth of winter wheat adapting to climate warming may face more low-temperature damage
- 2023
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Ingår i: International Journal of Climatology. - : Wiley. - 0899-8418 .- 1097-0088. ; 43:4, s. 1970-9
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Tidskriftsartikel (refereegranskat)abstract
- China's surface air temperature is increasing due to global warming, so it is interesting that how low temperatures would be changed during the growth period of winter wheat in future. We focused on the low temperatures of winter wheat from 2021 to 2050, using temperatures under the high emission scenario Representative Concentration Pathway 8.5 (RCP8.5) projected by the RegCM4.4 regional climate model. The results showed that the annual mean temperature was projected to increase by 0.42°C⋅decade−1 in the northern and by 0.35°C⋅decade−1 in the southern winter wheat region. Furthermore, the temperature was expected to increase rapidly in spring, which could advance the dates of flowering and the start of the grain-filling period. Using the genetic parameters determined by the calibration and validation of WOFOST and bias-corrected projected meteorological data, simulations of winter wheat growth were performed over the winter wheat region for 2021–2050. The simulated number of days to the flowering period of winter wheat for 2041–2050 was on average 6.5 days less than in 2021–2030, due to the spring warming. Because of the earlier start of the growing season, winter wheat could face negative effects by being subjected to low temperatures. Indeed, the number of low-temperature days was projected to increase by 110% from 2041 to 2050 compared to 2021–2030, and the number of killing degree days (KDDs) is projected to increase by 120% at the same time. If the number of days to flowering did not change, the number of low-temperature days and KDDs only changed slightly, showing that the negative influence of low temperature was mainly caused by the advancement of the flowering date. The effect of low temperature on growth was underestimated when the response of winter wheat growth to global warming was not considered.
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| 22. |
- 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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| 23. |
- Yang, Xifeng, et al.
(författare)
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Strain effect in determining the geometric shape of self-assembled quantum dot
- 2009
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Ingår i: Journal of Physics D. - : IOP Publishing. - 0022-3727 .- 1361-6463. ; 42:125414
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Tidskriftsartikel (refereegranskat)abstract
- The geometric shape of a self-assembled quantum dot (QD) formed by the strain-induced Stranski-Krastanov mode has been studied as a function of strain energy by the short-range valence-force-field approach. It has been shown by dynamic bond relaxation through strain energy minimization that for the most commonly used InAs QD in GaAs and InP matrices and Ge QD in Si matrix, a pyramidal shape is energy favoured over an hemispherical shape when the QD is not capped due to the lattice relaxation at the QD surface. When the QD becomes totally embedded in the background material, the elastic strain energy of a hemispherical InAs QD is minimal. The results agree with experimental observations. We further studied the coupling of strain fields of QDs in adjacent QD layers which shows that QDs in multiply stacked QD layers can be aligned along the layer growth direction in order to minimize the strain energy.
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| 24. |
- Zhu, Xin-wen, et al.
(författare)
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Effects of Al3(Sc1-xZrx) nano-particles on microstructure and mechanical properties of friction-stir-welded Al-Mg-Mn alloys
- 2023
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Ingår i: Transactions of Nonferrous Metals Society of China. - : Elsevier. - 1003-6326 .- 2210-3384. ; 33:1, s. 25-35
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Tidskriftsartikel (refereegranskat)abstract
- Microstructure and mechanical properties of friction-stir-welded Al-5.50Mg-0.45Mn and Al-5.50Mg- 0.45Mn-0.25Sc-0.10Zr (wt.%) alloys were investigated by tensile tests and microscopy methods. The results show that the yield strength, ultimate tensile strength and elongation of the Al-Mg-Mn joint are (191 +/- 3) MPa, (315 +/- 1) MPa and (4.8 +/- 1.9)%, respectively. The corresponding values of the Al-Mg-Mn-Sc-Zr joint are (288 +/- 5) MPa, (391 +/- 2) MPa and (3.4 +/- 1.0)%. The Al-Mg-Mn-Sc-Zr joint has smaller grain size, lower average misorientation angle and higher low-angle grain boundary fraction than the Al-Mg-Mn joint. Both the two joints fracture at the weld nugget zone (WNZ), and Al3(Sc1-xZrx) nano-particles with a mean size of (9.92 +/- 2.69) nm still remain in this "weakest zone". Theoretical calculation indicates that nano-particles can provide Orowan and grain boundary strengthening in WNZ, increasing the yield strength of the Al-Mg-Mn joint by 97 MPa.
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| 25. |
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| 26. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 27. |
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| 28. |
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| 29. |
- Chen, Yun, 1966, et al.
(författare)
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Characterization of VCAM-1-Binding Peptide-Functionalized Quantum Dots for Molecular Imaging of Inflamed Endothelium
- 2013
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 8:12
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Tidskriftsartikel (refereegranskat)abstract
- Inflammation-induced activation of endothelium constitutes one of the earliest changes during atherogenesis. New imaging techniques that allow detecting activated endothelial cells can improve the identification of persons at high cardiovascular risk in early stages. Quantum dots (QDs) have attractive optical properties such as bright fluorescence and high photostability, and have been increasingly studied and developed for bio-imaging and bio-targeting applications. We report here the development of vascular cell adhesion molecule-1 binding peptide (VCAM-1 binding peptide) functionalized QDs (VQDs) from amino QDs. It was found that the QD fluorescence signal in tumor necrosis factor alpha (TNF-alpha) treated endothelial cells in vitro was significantly higher when these cells were labeled with VQDs than amino QDs. The VQD labeling of TNF-alpha-treated endothelial cells was VCAM-1 specific since pre-incubation with recombinant VCAM-1 blocked cells' uptake of VQDs. Our ex vivo and in vivo experiments showed that in the inflamed endothelium, QD fluorescence signal from VQDs was also much stronger than that of amino QDs. Moreover, we observed that the QD fluorescence peak was significantly blue-shifted after VQDs interacted with aortic endothelial cells in vivo and in vitro. A similar blue-shift was observed after VQDs were incubated with recombinant VCAM-1 in tube. We anticipate that the specific interaction between VQDs and VCAM-1 and the blue-shift of the QD fluorescence peak can be very useful for VCAM-1 detection in vivo.
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| 30. |
- Chen, Zhihui, et al.
(författare)
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Exciton Polariton Contribution to the Stokes Shift in Colloidal Quantum Dots
- 2011
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 115:13, s. 5286-5293
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Tidskriftsartikel (refereegranskat)abstract
- We study the exciton polariton contribution to the Stokes shift in colloidal quantum dots (QDs). By detailed quantum mechanical description of light-matter interaction and temporal analysis of incident electromagnetic field across the QD using the finite-difference time-domain method, we have shown that the optical excitation of an exciton in the QD and its coupling with the excitation radiation (i.e., exciton polariton) induce strong variations in the dielectric constant of the QD which contribute significantly to the Stokes shift and cause modifications 50 in the absorption spectrum that agrees well with experiments.
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| 31. |
- Chen, Zhi-Hui, et al.
(författare)
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Comb-shaped photonic crystal structure for efficient broadband light diffraction and funnelling in solar cells
- 2012
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Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 99, s. 316-320
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Tidskriftsartikel (refereegranskat)abstract
- We present a comb-shaped photonic-crystal (PhC) rods-lattice structure of broadband light diffraction and funnelling for solar cell applications. It is shown that the photonic band of this PhC structure is very dispersive over a broad bandwidth so that light will be efficiently diffracted in the wavelength region of solar radiation. The PhC structure also creates resonance modes leading to further diffraction and funnelling of light so that the light propagates in many pathways in the whole PhC lattice region, which will greatly facilitate light-matter interaction when light-absorbing elements are embedded in the PhC structure. The proposed structure is also valid for photodetection applications.
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| 32. |
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| 33. |
- Chen, Zhihui, 1984-
(författare)
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Light manipulation in micro and nano photonic materials and structures
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Light manipulation is an important method to enhance the light-matter interactions in micro and nano photonic materials and structures by generating usefulelectric field components and increasing time and pathways of light propagationthrough the micro and nano materials and structures. For example, quantum wellinfrared photodetector (QWIP) cannot absorb normal incident radiation so thatthe generation of an electric field component which is parallel to the original incident direction is a necessity for the function of QWIP. Furthermore, the increaseof time and pathways of light propagation in the light-absorbing quantum wellregion will increase the chance of absorbing the photons.The thesis presents the theoretical studies of light manipulation and light-matter interaction in micro and nano photonic materials and structures, aiming atimproving the performance of optical communication devices, photonic integrateddevices and photovoltaic devices.To design efficient micro and nano photonic devices, it is essential to knowthe time evolution of the electromagnetic (EM) field. Two-dimensional and three-dimensional finite-difference time-domain (FDTD) methods have been adopted inthe thesis to numerically solve the Maxwell equations in micro and nano photonicmaterials and structures.Light manipulation in micro and nano material and structures studied in thisthesis includes: (1) light transport in the photonic crystal (PhC) waveguide, (2)light diffraction by the micro-scale dielectric PhC and metallic PhC structures(gratings); and (3) exciton-polaritons of semiconductor quantum dots, (4) surfaceplasmon polaritons at semiconductor-metallic material interface for subwavelengthlight control. All these aspects are found to be useful in optical devices of multiplebeam splitter, quantum well/dot infrared photodetectors, and solar cells.
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| 34. |
- Chen, Zhihui, et al.
(författare)
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Multiple beam splitting to free space from a V groove in a photonic crystal waveguide
- 2011
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Ingår i: Applied physics. B, Lasers and optics (Print). - : Springer Science and Business Media LLC. - 0946-2171 .- 1432-0649. ; 102:4, s. 857-861
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Tidskriftsartikel (refereegranskat)abstract
- We present multiple-beam splitting to free space from a V groove in a two-dimensional photonic crystal waveguide (PCW) with a few additional dielectric rods at the exit of the PCW. Numerical study shows that 'one-beam-in to two-beams-out' (one-to-two, also denoted as Y-shaped), one-to-three, and one-to-five beam splittings can be easily realized over a wide bandwidth, and the split beams have remarkable properties such as symmetric energy distributions and high directional transmissions. Off-axis directional emission can also be achieved by simple displacements of the additional rods at the exit of the PCW.
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| 35. |
- Chen, Zhihui, et al.
(författare)
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Time-resolved photocurrents in quantum well/dot infrared photodetectors with different optical coupling structures
- 2012
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 100:4, s. 043502-
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Tidskriftsartikel (refereegranskat)abstract
- Temporal developments of photocurrents excited by an infrared radiation pulse in quantum well/dot infrared photodetectors with different optical coupling structures have been theoretically studied. It is shown that the light diffraction in a conventional reflective grating structure is a near-field effect containing severe crosstalk from neighboring pixels. A concave reflector not only eliminates the crosstalk but also strongly diffracts and focuses the incident electric field into deep active layers, which significantly increases the photocurrents in the photodetectors.
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| 36. |
- Cheung, Hiu Ying, et al.
(författare)
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Older People’s Choice of the Community-based Care: A Welfare Pluralism Perspective
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The complex interactions among multiple service providers pose challenges to the delivery of community-based care for older people. Through the lens of the welfare pluralism theory, this study provides the first understanding of older people’s decisions regarding within-family /community-based care under complex interactions among the government, enterprises, communities, and families. Based on a survey of older people in 2,883 corresponding families and 184 communities in China, we utilize a logit regression to empirically examine the factors that influence older people’s care decisions, as identified by an equilibrium model. We find that the government subsidy and local wage level effectively promote older people’s decisions to community-based care. We highlight the importance of governments’ direct care provisions in promoting aging in place and efforts to mitigate regional inequalities.
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| 37. |
- de Melo, Fernando Menegatti, et al.
(författare)
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Superparamagnetic Maghemite-Based CdTe Quantum Dots as Efficient Hybrid Nanoprobes for Water-Bath Magnetic Particle Inspection
- 2018
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Ingår i: ACS Applied Nano Materials. - : American Chemical Society (ACS). - 2574-0970. ; 1:6, s. 2858-2868
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Tidskriftsartikel (refereegranskat)abstract
- Fluorescent water-based cadmium telluride quantum dots (QDs) and citrate-functionalized maghemite nanoparticles (MghNPs) were synthesized and assembled together (MghNPs@QDs) through electrostatic interactions by using cetyltrimethylammonium bromide (CTAB) as a linker and steric spacer to minimize the Forster resonance energy transfer (FRET) restriction. A whole family of hybrid and multifunctional nanoparticles has been successfully obtained, exhibiting good performance in nondestructive water-bath magnetic particle inspection (MPI) assays.
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| 38. |
- Desjardins, Kewin, et al.
(författare)
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Characterization of a back-illuminated CMOS camera for soft x-ray coherent scattering
- 2019
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Ingår i: Proceedings of the 13th International Conference on Synchrotron Radiation Instrumentation, SRI 2018. - : Author(s). - 9780735417823 ; 2054
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Konferensbidrag (refereegranskat)abstract
- A commercial scientific camera has been adapted and characterized at the SOLEIL Synchrotron with the aim to improve the acquisition capabilities on the soft X-ray coherent scattering experimental station at SEXTANTS beamline. This device is equipped by the last generation of back side illuminated scientific CMOS (BSI-sCMOS) of 2048 by 2048 pixels of 11 μm2 able to acquire low noise images with a frame rate up to 48 Hz. The camera's performance measurements have been done and shows a good level of readout noise, a large full-well capacity, a medium dark current and a good homogeneity, respectively, 1.6 e- rms (in High Gain mode), 80 000 e- (in Low Gain mode),<5 e-/pixel/s and ∼ 1%. The quantum efficiency (QE) measurement has been performed at the soft x-ray branch of the METROLOGIE beamline and gives a relatively good agreement with the expected theoretical values. Finally, the demonstration of the camera's efficiency and of the gain in useful time measurement related to the high frame rate have been performed with a series of Airy patterns images compared with an image recorded using the standard BSI-CDD already in operation at the SEXTANTS beamline.
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| 39. |
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| 40. |
- Engström, Olof, 1943, et al.
(författare)
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Electron capture cross sections of InAs/GaAs quantum dots
- 2004
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 85:14, s. 2908-2910
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Tidskriftsartikel (refereegranskat)abstract
- The thermal emission rates of electrons from InAs/GaAs quantum dots were measured, to found the capture cross sections in the extremely high region of 10-11-10-10 cm2. An additional method based on a static measurement at thermal equilibrium was used where the Fermi level was positioned at the free energy level of the quantum dot s shell. A Schottky diode with a plane of QDs grown in its depletion region and back-biased in such a way that the Fermi level coincides with the electron energy level. The Fermi level passes the lowest energy level of the QD, at the voltage marked by Vp in the graphs.
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Fan, Ying, et al.
(författare)
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Door-in-the-face heuristics: Intermediaries’ diversion in rental markets
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This paper investigates how intermediaries with information advantages divert consumer search in rental markets and lead to inefficient outcomes. Using unique data on tenants’ initial preferences and property-visit records, we find that intermediaries deliberately prioritize the exhibition of properties distant from tenants’ preferences in their property-showing sequences and divert the visit route toward unsolicited properties. Moreover, such diversion patterns are dynamically adjusted according to the instantaneous feedback from tenants. By using diversion strategies to affect and project consumers’ preferences and willingness to pay, intermediaries can benefit from two channels, i.e., 1) distorting transaction outcomes and achieving higher commissions and 2) facilitating deals for less-favorable properties. We also provide evidence for the successive approximations of intermediaries’ diversion strategies and their implications for tenant discrimination.
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| 45. |
- Fan, Yanmiao, et al.
(författare)
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Fluorescent silicon nanoparticles as a potential capaturing and imaging agent for Staphylococcus aureus
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Nanomaterials, with various shapes and specific physicochemical properties, have attracted a lot of interest in the biomedical fields. Fluorescent silicon nanoparticles (SiNPs) have shown promise as immunofluorescent cellular imaging agents. In this study, SiNPs were synthesized to explore their potential as bacterial imaging agents. Silicon nanoparticles with amino groups on the surface were prepared using microwave-assisted synthesis method using trisodium citrate as the reducing agent. The obtained SiNPs were characterized using dynamic light scattering (DLS), UV−vis absorption spectroscopy and fluorescence spectrophotometer. And SiNPs were used to study their interactions with both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). The interactions between the prepared SiNPs and bacteria were monitored by the fluorescence microscope, and SiNPs showed a strong interaction with S. aureus. SEM was used to study the morphological changes of S. aureus, and we found that the cell membranes of S. aureus became damaged after the interaction with SiNPs. The amino groups on the surfaces of SiNPs could also be functionalized with other functional groups for other applications.
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| 46. |
- Fan, Ying, et al.
(författare)
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Search frictions in rental markets : Evidence from urban China
- 2024
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Ingår i: China economic review. - : Elsevier BV. - 1043-951X .- 1873-7781. ; 83
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we study consumer search in a housing market subject to objective frictions induced by intermediaries and psychological frictions intrinsic to tenants themselves. Using rental data from a leading real estate brokerage company during 2016 and 2018, we find a unimodal distribution of objective search frictions and a bimodal distribution of psychological search frictions revealed by tenants' search behaviors. This bimodal distribution originates from divergent search strategies of tenants with different search criteria. Furthermore, psychological search frictions explain the deviation between a tenant's actual choice and stated preference, and enhance the degree of overpay/mark-up in the deal. These effects of psychological frictions led by divergent search strategies hold when we consider the expertise/incentive of agents and the rigidity/opportunity cost of tenants' search. Aggregately, psychological search frictions result in a dispersed and asymmetric distribution of rent residuals.
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| 47. |
- Feng, Dawei, et al.
(författare)
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Stable metal-organic frameworks containing single-molecule traps for enzyme encapsulation
- 2015
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 6, s. 5979-
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Tidskriftsartikel (refereegranskat)abstract
- Enzymatic catalytic processes possess great potential in chemical manufacturing, including pharmaceuticals, fuel production and food processing. However, the engineering of enzymes is severely hampered due to their low operational stability and difficulty of reuse. Here, we develop a series of stable metal-organic frameworks with rationally designed ultra-large mesoporous cages as single-molecule traps (SMTs) for enzyme encapsulation. With a high concentration of mesoporous cages as SMTs, PCN-333(Al) encapsulates three enzymes with record-high loadings and recyclability. Immobilized enzymes that most likely undergo single-enzyme encapsulation (SEE) show smaller Km than free enzymes while maintaining comparable catalytic efficiency. Under harsh conditions, the enzyme in SEE exhibits better performance than free enzyme, showing the effectiveness of SEE in preventing enzyme aggregation or denaturation. With extraordinarily large pore size and excellent chemical stability, PCN-333 may be of interest not only for enzyme encapsulation, but also for entrapment of other nanoscaled functional moieties.
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| 48. |
- Fontana, Jacopo Maria, et al.
(författare)
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Transport and release of colloidal 3-mercaptopropionic acid-coated CdSe-CdS/ZnS core-multishell quantum dots in human umbilical vein endothelial cells
- 2017
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Ingår i: International Journal of Nanomedicine. - : Dove Medical Press Ltd. - 1176-9114 .- 1178-2013. ; 12, s. 8615-8629
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Tidskriftsartikel (refereegranskat)abstract
- Colloidal semiconductor quantum dots (QDs) have been extensively researched and developed for biomedical applications, including drug delivery and biosensing assays. Hence, it is pivotal to understand their behavior in terms of intracellular transport and toxicological effects. In this study, we focused on 3-mercaptopropionic acid-coated CdSe-CdS/ZnS core-multishell quantum dots (3MPA-QDs) converted from the as-grown octadecylamine-coated quantum dots (ODA-QDs) and their direct and dynamic interactions with human umbilical vein endothelial cells (HUVECs). Live cell imaging using confocal fluorescence microscopy showed that 3MPAQDs first attached to and subsequently aggregated on HUVEC plasma membrane similar to 25 min after QD deposition. The aggregated QDs started being internalized at similar to 2 h and reached their highest internalization degree at similar to 24 h. They were released from HUVECs after similar to 48 h. During the 48 h period, the HUVECs responded normally to external stimulations, grew, proliferated and wound healed without any perceptible apoptosis. Furthermore, 1) 3MPA-QDs were internalized in newly formed LysoTracker-stained early endosomes; 2) adenosine 5'-triphosphateinduced [Ca2+](i) modulation caused a transient decrease in the fluorescence of 3MPA-QDs that were attached to the plasma membrane but a transient increase in the internalized 3MPA-QDs; and 3) fluorescence signal modulations of co-stained LysoTracker and QDs induced by the lysosomotropic agent Gly-Phe-beta-naphthylamide were spatially co-localized and temporally synchronized. Our findings suggest that 3MPA-QDs converted from ODA-QDs are a potential nontoxic fluorescent probe for future use in clinical applications. Moreover, the photophysical strategy and techniques reported in this work are easily applicable to study of direct interactions between other nanoparticles and live cells; contributing to awareness and implementation of the safe applications of nanoparticles.
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| 49. |
- Fu, Le, et al.
(författare)
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Liquid-phase sintering of ZrO2-based nanocrystalline glass-ceramics achieved by multielement co-doping
- 2023
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Ingår i: Journal of The American Ceramic Society. - : John Wiley & Sons. - 0002-7820 .- 1551-2916. ; 106:4, s. 2702-2715
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Tidskriftsartikel (refereegranskat)abstract
- Liquid-phase sintering (LPS) is an effective pathway to assist the densification of ceramics. However, it has seldom been used to densify glass-ceramics. In the present study, a multielement co-doping strategy has been utilized to achieve LPS of a ZrO2-SiO2 nanocrystalline glass-ceramic. Compared with undoped samples densified by solid-state sintering, doping of equimolar Al, Y, and Ca promoted the densification of the glass-ceramic at lower temperatures with a faster densification rate. Ternary doping enhanced coarsening of ZrO2 nanocrystallites during sintering and annealing. The distribution of dopants was carefully observed with X-ray energy-dispersive spectrometry technique in scanning electron transmission microscopy mode. Results showed that the three dopants showed different distribution behaviors. After sintering, Y dopants were predominately distributed in ZrO2 nanocrystallites, whereas parts of Al and Ca dopants were distributed in ZrO2 nanocrystallites and part of them co-segregated at the ZrO2/SiO2 heterointerfaces. Meanwhile, the segregation of Ca dopant at some intergranular films among ZrO2 nanocrystallites was observed. Redistribution of dopants did not occur during annealing.
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| 50. |
- Fu, Le, et al.
(författare)
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Structural integrity and damage of glass-ceramics after He ion irradiation : Insights from ZrO2-SiO2 nanocrystalline glass-ceramics
- 2023
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Ingår i: Journal of the European Ceramic Society. - : Elsevier. - 0955-2219 .- 1873-619X. ; 43:6, s. 2624-2633
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Tidskriftsartikel (refereegranskat)abstract
- Developing new radiation-resistant materials and understanding the structural damages caused by radiation are persistent goals of material scientists. Here, we report on the structural integrity and damage to ZrO2-SiO2 nanocrystalline glass-ceramics after radiation with 1.4 MeV He ions at three different fluences: 1.0 x 1016 ions/ cm2 (low), 5.0 x 1016 ions/cm2 (moderate), and 1.0 x 1017 ions/cm2 (high) at 500 degrees C. Grazing incident X-ray diffraction shows the tetragonal-ZrO2 to monoclinic-ZrO2 phase transformation induced by microstrain from the irradiation. The addition of yttrium indicated tetragonal-ZrO2 stabilization effect during irradiation. The irra-diated glass-ceramics show a Raman signal-enhancement effect probably related to the electronic structure changes of the amorphous SiO2 component in the glass-ceramics. The formation of microcracks and lattice de-fects within ZrO2 nanocrystallites is the main structural damage caused by irradiation. There was no observable amorphization of ZrO2 nanocrystallites due to irradiation. No obvious He bubbles were detected, either. The formation of microcracks results in a decrease of in the nanohardness of the glass-ceramics. The results provide fundamental experimental data to understand the structural integrity and damage caused by radiation, which could be useful to design radiation-resistant nanocrystalline glass-ceramics for extremely radioactive environments.
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