| 1. |
- Beal, Jacob, et al.
(author)
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Robust estimation of bacterial cell count from optical density
- 2020
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In: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Journal article (peer-reviewed)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
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| 3. |
- Kristanl, Matej, et al.
(author)
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The Seventh Visual Object Tracking VOT2019 Challenge Results
- 2019
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In: 2019 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW). - : IEEE COMPUTER SOC. - 9781728150239 ; , s. 2206-2241
-
Conference paper (peer-reviewed)abstract
- The Visual Object Tracking challenge VOT2019 is the seventh annual tracker benchmarking activity organized by the VOT initiative. Results of 81 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis as well as the standard VOT methodology for long-term tracking analysis. The VOT2019 challenge was composed of five challenges focusing on different tracking domains: (i) VOT-ST2019 challenge focused on short-term tracking in RGB, (ii) VOT-RT2019 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2019 focused on long-term tracking namely coping with target disappearance and reappearance. Two new challenges have been introduced: (iv) VOT-RGBT2019 challenge focused on short-term tracking in RGB and thermal imagery and (v) VOT-RGBD2019 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2019, VOT-RT2019 and VOT-LT2019 datasets were refreshed while new datasets were introduced for VOT-RGBT2019 and VOT-RGBD2019. The VOT toolkit has been updated to support both standard short-term, long-term tracking and tracking with multi-channel imagery. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website(1).
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| 4. |
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- 2019
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Journal article (peer-reviewed)
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| 5. |
- Klionsky, Daniel J., et al.
(author)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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In: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
-
Research review (peer-reviewed)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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| 6. |
- Kristan, Matej, et al.
(author)
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The Sixth Visual Object Tracking VOT2018 Challenge Results
- 2019
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In: Computer Vision – ECCV 2018 Workshops. - Cham : Springer Publishing Company. - 9783030110086 - 9783030110093 ; , s. 3-53
-
Conference paper (peer-reviewed)abstract
- The Visual Object Tracking challenge VOT2018 is the sixth annual tracker benchmarking activity organized by the VOT initiative. Results of over eighty trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis and a “real-time” experiment simulating a situation where a tracker processes images as if provided by a continuously running sensor. A long-term tracking subchallenge has been introduced to the set of standard VOT sub-challenges. The new subchallenge focuses on long-term tracking properties, namely coping with target disappearance and reappearance. A new dataset has been compiled and a performance evaluation methodology that focuses on long-term tracking capabilities has been adopted. The VOT toolkit has been updated to support both standard short-term and the new long-term tracking subchallenges. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website (http://votchallenge.net).
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| 7. |
- Jarvis, Erich D., et al.
(author)
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Whole-genome analyses resolve early branches in the tree of life of modern birds
- 2014
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6215, s. 1320-1331
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Journal article (peer-reviewed)abstract
- To better determine the history of modern birds, we performed a genome-scale phylogenetic analysis of 48 species representing all orders of Neoaves using phylogenomic methods created to handle genome-scale data. We recovered a highly resolved tree that confirms previously controversial sister or close relationships. We identified the first divergence in Neoaves, two groups we named Passerea and Columbea, representing independent lineages of diverse and convergently evolved land and water bird species. Among Passerea, we infer the common ancestor of core landbirds to have been an apex predator and confirm independent gains of vocal learning. Among Columbea, we identify pigeons and flamingoes as belonging to sister clades. Even with whole genomes, some of the earliest branches in Neoaves proved challenging to resolve, which was best explained by massive protein-coding sequence convergence and high levels of incomplete lineage sorting that occurred during a rapid radiation after the Cretaceous-Paleogene mass extinction event about 66 million years ago.
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| 8. |
- Ruilope, LM, et al.
(author)
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Design and Baseline Characteristics of the Finerenone in Reducing Cardiovascular Mortality and Morbidity in Diabetic Kidney Disease Trial
- 2019
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In: American journal of nephrology. - : S. Karger AG. - 1421-9670 .- 0250-8095. ; 50:5, s. 345-356
-
Journal article (peer-reviewed)abstract
- <b><i>Background:</i></b> Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. <b><i>Patients and</i></b> <b><i>Methods:</i></b> The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate ≥25 mL/min/1.73 m<sup>2</sup> and albuminuria (urinary albumin-to-creatinine ratio ≥30 to ≤5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level α = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. <b><i>Conclusions:</i></b> FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049.
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| 9. |
- Zhang, Guojie, et al.
(author)
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Comparative genomics reveals insights into avian genome evolution and adaptation
- 2014
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6215, s. 1311-1320
-
Journal article (peer-reviewed)abstract
- Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits.
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| 10. |
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| 11. |
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| 12. |
- Kristan, Matej, et al.
(author)
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The Ninth Visual Object Tracking VOT2021 Challenge Results
- 2021
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In: 2021 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW 2021). - : IEEE COMPUTER SOC. - 9781665401913 ; , s. 2711-2738
-
Conference paper (peer-reviewed)abstract
- The Visual Object Tracking challenge VOT2021 is the ninth annual tracker benchmarking activity organized by the VOT initiative. Results of 71 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in recent years. The VOT2021 challenge was composed of four sub-challenges focusing on different tracking domains: (i) VOT-ST2021 challenge focused on short-term tracking in RGB, (ii) VOT-RT2021 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2021 focused on long-term tracking, namely coping with target disappearance and reappearance and (iv) VOT-RGBD2021 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2021 dataset was refreshed, while VOT-RGBD2021 introduces a training dataset and sequestered dataset for winner identification. The source code for most of the trackers, the datasets, the evaluation kit and the results along with the source code for most trackers are publicly available at the challenge website(1).
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| 13. |
- Liu, Tao, et al.
(author)
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16% efficiency all-polymer organic solar cells enabled by a finely tuned morphology via the design of ternary blend
- 2021
-
In: Joule. - : CELL PRESS. - 2542-4351. ; 5:4, s. 914-930
-
Journal article (peer-reviewed)abstract
- A SUMMARY There is an urgent demand for all-polymer organic solar cells (AP-OSCs) to gain higher efficiency. Here, we successfully improve the performance to 16.09% by introducing a small amount of BN-T, a B <- N-type polymer acceptor, into the PM6:PY-IT blend. It has been found that BN-T makes the active layer, based on the PM6:PY-IT:BN-T ternary blend, more crystalline but meanwhile slightly reduces the phase separation, leading to enhancement of both exciton harvesting and charge transport. From a thermodynamic viewpoint, BN-T prefers to reside between PM6 and PY-IT, and the fraction of this fine-tunes the morphology. Besides, a significantly reduced nonradiative energy loss occurs in the ternary blend, along with the coexistence of energy and charge transfer between the two acceptors. The progressive performance facilitated by these improved properties demonstrates that AP-OSCs can possibly comparably efficient with those based on small molecule acceptors, further enhancing the competitiveness of this device type.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
- Bailey, Matthew H., et al.
(author)
-
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
- 2020
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
-
Journal article (peer-reviewed)abstract
- The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
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| 22. |
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| 23. |
- Kristan, Matej, et al.
(author)
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The Visual Object Tracking VOT2014 Challenge Results
- 2015
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In: COMPUTER VISION - ECCV 2014 WORKSHOPS, PT II. - Cham : Springer. - 9783319161808 - 9783319161815 ; , s. 191-217
-
Conference paper (peer-reviewed)abstract
- The Visual Object Tracking challenge 2014, VOT2014, aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 38 trackers are presented. The number of tested trackers makes VOT 2014 the largest benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the appendix. Features of the VOT2014 challenge that go beyond its VOT2013 predecessor are introduced: (i) a new VOT2014 dataset with full annotation of targets by rotated bounding boxes and per-frame attribute, (ii) extensions of the VOT2013 evaluation methodology, (iii) a new unit for tracking speed assessment less dependent on the hardware and (iv) the VOT2014 evaluation toolkit that significantly speeds up execution of experiments. The dataset, the evaluation kit as well as the results are publicly available at the challenge website (http://votchallenge.net).
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| 24. |
- Li, Hongjie J., et al.
(author)
-
Collective band structures in the Tc-99 nucleus
- 2015
-
In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 91:5
-
Journal article (peer-reviewed)abstract
- Excited states in Tc-99 with energies up to 6 MeV have been populated using the Zr-96(Li-7, 4n)Tc-99 reaction with a laboratory beam energy of 35 MeV. Coincident gamma rays from excited nuclei produced in the reactions were detected using an array of coaxial, planar, and clover-type high-purity germanium detectors. A total of 60 new gamma-ray transitions and 21 new levels are identified and placed into a new level scheme. Two collective bands assigned to be built on the pi g(9/2)[422]5/2(+) and pi p(1/2)[301]1/2(-) Nilsson configurations have been extended with spins up to 35/2 and 33/2 h, respectively. Backbending and signature inversion have been observed in the yrast band. The large signature splitting of the positive-parity band in Tc-99 may be caused by a triaxial deformation, which agrees well with the electromagnetic properties, theoretical calculations based on total Routhian surface, and triaxial particle-rotor model calculations.
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| 25. |
- Li, Wei, et al.
(author)
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Non-lab and semi-lab algorithms for screening undiagnosed diabetes : A cross-sectional study
- 2018
-
In: EBioMedicine. - : ELSEVIER SCIENCE BV. - 2352-3964. ; 35, s. 307-316
-
Journal article (peer-reviewed)abstract
- Background: The terrifying undiagnosed rate and high prevalence of diabetes have become a public emergency. A high efficiency and cost-effective early recognition method is urgently needed. We aimed to generate innovative, user-friendly nomograms that can be applied for diabetes screening in different ethnic groups in China using the non-lab or noninvasive semi-lab data. Methods: This multicenter, multi-ethnic, population-based, cross-sectional study was conducted in eight sites in China by enrolling subjects aged 20-70. Sociodemographic and anthropometric characteristics were collected. Blood and urine samples were obtained 2 h following a standard 75 g glucose solution. In the final analysis, 10,794 participants were included and randomized into model development (n - 8096) and model validation (n = 2698) group with a ratio of 3:1. Nomograms were developed by the stepwise binary logistic regression. The nomograms were validated internally by a bootstrap sampling method in the model development set and externally in the model validation set. The area under the receiver operating characteristic curve (AUC) was used to assess the screening performance of the nomograms. Decision curve analysis was applied to calculate the net benefit of the screening model. Results: The overall prevalence of undiagnosed diabetes was 9.8% (1059/10794) according to ADA criteria. The non-lab model revealed that gender, age, body mass index, waist circumference, hypertension, ethnicities, vegetable daily consumption and family history of diabetes were independent risk factors for diabetes. By adding 2 h post meal glycosuria qualitative to the non-lab model, the semi-lab model showed an improved Akaike information criterion (AIC: 4506 to 3580). The AUC of the semi-lab model was statistically larger than the non-lab model (0.868 vs 0.763, P < 0.001). The optimal cutoff probability in semi-lab and non-lab nomograms were 0.088 and 0.098, respectively. The sensitivity and specificity were 76.3% and 81.6%, respectively in semi-lab nomogram, and 72.1% and 673% in non-lab nomogram at the optimal cut off point. The decision curve analysis also revealed a bigger decrease of avoidable OGTT test (52 per 100 subjects) in the semi-lab model compared to the non-lab model (36 per 100 subjects) and the existed New Chinese Diabetes Risk Score (NCDRS, 35 per 100 subjects). Conclusion: The non-lab and semi-lab nomograms appear to be reliable tools for diabetes screening, especially in developing countries. However, the semi-lab model outperformed the non-lab model and NCDRS prediction systems and might be worth being adopted as decision support in diabetes screening in China.
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| 26. |
- Li, Xiaofeng, et al.
(author)
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双色光束增强飞秒激光氮气标记示踪测速技术的研究
- 2022
-
In: Kung Cheng Je Wu Li Hsueh Pao/Journal of Engineering Thermophysics. - 0253-231X. ; 43:10, s. 2826-2830
-
Journal article (peer-reviewed)abstract
- In this work, the fluorescence of FLEET (femtosecond laser electron excited tagging) was enhanced by two color femtosecond laser. the intensity of FLEET was increased about 20% with two laser pulses that were 400 μJ/pulse at 266 nm and 3 mJ/pulse at 800 nm, and the results indicated that there was nearly no influence on lifetime and wavelength of fluorescence from FLEET. This result provides many information for the following studies.
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| 27. |
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| 28. |
- Mahajan, Anubha, et al.
(author)
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Refining the accuracy of validated target identification through coding variant fine-mapping in type 2 diabetes
- 2018
-
In: Nature Genetics. - : Nature Publishing Group. - 1061-4036 .- 1546-1718. ; 50:4, s. 559-571
-
Journal article (peer-reviewed)abstract
- We aggregated coding variant data for 81,412 type 2 diabetes cases and 370,832 controls of diverse ancestry, identifying 40 coding variant association signals (P < 2.2 × 10−7); of these, 16 map outside known risk-associated loci. We make two important observations. First, only five of these signals are driven by low-frequency variants: even for these, effect sizes are modest (odds ratio ≤1.29). Second, when we used large-scale genome-wide association data to fine-map the associated variants in their regional context, accounting for the global enrichment of complex trait associations in coding sequence, compelling evidence for coding variant causality was obtained for only 16 signals. At 13 others, the associated coding variants clearly represent ‘false leads’ with potential to generate erroneous mechanistic inference. Coding variant associations offer a direct route to biological insight for complex diseases and identification of validated therapeutic targets; however, appropriate mechanistic inference requires careful specification of their causal contribution to disease predisposition.
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| 29. |
- Pecunia, Vincenzo, et al.
(author)
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Roadmap on energy harvesting materials
- 2023
-
In: Journal of Physics. - : IOP Publishing. - 2515-7639. ; 6:4
-
Journal article (peer-reviewed)abstract
- Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.
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| 30. |
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| 31. |
- Wan, Lu Ming, et al.
(author)
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Heparanase Facilitates PMA-Induced Megakaryocytic Differentiation in K562 Cells via Interleukin 6/STAT3 Pathway
- 2020
-
In: Thrombosis and Haemostasis. - : GEORG THIEME VERLAG KG. - 0340-6245 .- 2567-689X. ; 120:4, s. 647-657
-
Journal article (peer-reviewed)abstract
- Heparanase (HPSE) is an endo-beta-D-glucuronidase that cleaves heparan sulfate and hence participates in remodeling of the extracellular matrix, leading to release of cytokines that are immobilized by binding to heparan sulfate proteoglycans (HSPGs), and consequently activating signaling pathways. This function of HPSE is correlated to its expression level that is normally very low in majority of the tissues. Exceptionally, human platelets express high level of HPSE, suggesting a unique physiological role in this cell. Using K562 cell line, we found a progressive increase of HPSE during the megakaryocytic differentiation. Analysis of a series of megakaryocytic differentiation-related heparin-binding proteins (HBPs) in the cell culture medium revealed an exclusive positive correlation between the level of interleukin 6 (IL-6) and HPSE expression. IL-6 modulated megakaryocytic differentiation through activation of STAT3. Further, we demonstrated that overexpression of HPSE potentiates megakaryocytic differentiation, whereas elimination of HPSE led to a delayed differentiation. This function of HPSE is associated with its activity, as overexpression of inactive HPSE had no effect on IL-6 production and megakaryocytic differentiation. The role of HPSE is further supported by the observation in an umbilical cord blood CD34+ cells megakaryocytic differentiation model. Our data propose a novel role for HPSE in platelets production by a HPSE/IL-6/STAT3 positive feedback loop that specifically regulates megakaryocytes maturation.
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| 32. |
- Barucca, G., et al.
(author)
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The potential of Λ and Ξ- studies with PANDA at FAIR
- 2021
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In: European Physical Journal A. - : Springer Nature. - 1434-6001 .- 1434-601X. ; 57:4
-
Journal article (peer-reviewed)abstract
- The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯ p→ Λ¯ Λ and p¯ p→ Ξ¯ +Ξ-. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.
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| 33. |
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| 34. |
- Erni, W., et al.
(author)
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Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker
- 2013
-
In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 49:2
-
Journal article (peer-reviewed)abstract
- This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described.
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| 35. |
- Gao, Qiang, et al.
(author)
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Femtosecond-laser electronic-excitation tagging velocimetry using a 267 nm laser
- 2019
-
In: Sensors and Actuators, A: Physical. - : Elsevier BV. - 0924-4247. ; 287, s. 138-142
-
Journal article (peer-reviewed)abstract
- Femtosecond (fs)-laser electronic-excitation tagging velocimetry (FLEET) in a nitrogen flow field using a 267 nm laser was performed under the condition of fs-laser filamentation. The filamentous properties and their effects on velocity measurements were investigated and were compared with those of an 800 nm fs-laser. The results show that the required energy of the 267 nm laser pulse is as low as hundreds of μJ, and this is beneficial for reducing the potential perturbations to the flow flied. The filaments induced by the 267 nm laser are longer and thinner than are those induced by the 800 nm laser, which enlarges the velocity measurements region, and a precision of 1.3% was achieved.
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| 36. |
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| 37. |
- Guo, Xuewen, et al.
(author)
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Understanding the effect of N2200 on performance of J71 : ITIC bulk heterojunction in ternary non-fullerene solar cells
- 2019
-
In: Organic electronics. - : Elsevier. - 1566-1199 .- 1878-5530. ; 71, s. 65-71
-
Journal article (peer-reviewed)abstract
- None-fullerene solar cells with ternary architecture have attracted much attention because it is an effective approach for boosting the device power conversion efficiency. Here, the crystalline polymer N2200 as the third component is integrated into J71: ITIC bulk heterojunction. A series of characterizations indicate that N2200 could increase photo-harvesting, balanced hole and electron mobilities, enhanced exciton dissociation, and suppressed charge recombination, which result in the comprehensive improvement of open circuit voltage, short circuit current and fill factor in the device. Moreover, after introduction of N2200, the morphology of the ternary active layer is optimized, and the film crystallinity is improved. This work demonstrates that adding a small quantity of high crystallization acceptor into non-fullerene donor: acceptor mixture is a promising strategy toward developing high-performance organic solar cells.
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| 38. |
- Han, Lei, et al.
(author)
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Simultaneous measurements of velocity and concentration of gas flow using femtosecond laser-induced chemiluminescence
- 2022
-
In: Optics and Lasers in Engineering. - : Elsevier BV. - 0143-8166. ; 155
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Journal article (peer-reviewed)abstract
- The mixing process in a gas flow plays a crucial role in chemical reactions, and simultaneous measurements of both velocity and mixture fraction are desired to fathom the process. Here, we report a scheme for simultaneously measuring both velocity and concentration by femtosecond laser-induced chemiluminescence. The femtosecond laser would induce chemical reactions that generate CN radicals in the B state. The transition of CN (X-B) would emit fluorescence with both strong intensity and long duration, and the decay of the fluorescence versus time showed prominent benefits for the simultaneous measurement. This measurement was accomplished by an ICCD camera worked in the on-chip multi-exposure mode, i.e., the camera had two exposures in succession to capture two luminescent lines on one image. The first line was used to measure the methane concentration and hence, the mixture fraction through a calibration procedure. The second line was the first line displaced by the flow in a known time interval and we demonstrate an algorithm to derive the one dimensional-two components velocity fields from the line shapes of the luminescent lines. The detection limit of the concentration is estimated to be 152 ppm and the minimum measurable velocity is estimated to be 5 m/s.
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| 39. |
- Huang, Liping, et al.
(author)
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Interim effects of salt substitution on urinary electrolytes and blood pressure in the China Salt Substitute and Stroke Study (SSaSS).
- 2020
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In: American Heart Journal. - : Elsevier BV. - 0002-8703 .- 1097-6744. ; 221, s. 136-145
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Journal article (peer-reviewed)abstract
- The Salt Substitute and Stroke Study is an ongoing 5-year large-scale cluster randomized trial investigating the effects of potassium-enriched salt substitute compared to usual salt on the risk of stroke. The study involves 600 villages and 20,996 individuals in rural China. Intermediate risk markers were measured in a random subsample of villages every 12 months over 3 years to track progress against key assumptions underlying study design. Measures of 24-hour urinary sodium, 24-hour urinary potassium, blood pressure and participants' use of salt substitute were recorded, with differences between intervention and control groups estimated using generalized linear mixed models. The primary outcome of annual event rate in the two groups combined was determined by dividing confirmed fatal and non-fatal strokes by total follow-up time in the first 2 years. The mean differences (95% CI) were -0.32 g (-0.68 to 0.05) for 24-hour urinary sodium, +0.77 g (+0.60 to +0.93) for 24-hour urinary potassium, -2.65 mmHg (-4.32 to -0.97) for systolic blood pressure and +0.30 mmHg (-0.72 to +1.32) for diastolic blood pressure. Use of salt substitute was reported by 97.5% in the intervention group versus 4.2% in the control group (P<.0001). The overall estimated annual event rate for fatal and non-fatal stroke was 3.2%. The systolic blood pressure difference and the annual stroke rate were both in line with the statistical assumptions underlying study design. The trial should be well placed to address the primary hypothesis at completion of follow-up.
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| 40. |
- Jiang, Tao, et al.
(author)
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Tetraphenylethene end-capped diketopyrrolopyrrole fluorogens with AIE and large two-photon absorption cross-sections features and application in bioimaging
- 2016
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In: Dyes and pigments. - : Elsevier. - 0143-7208 .- 1873-3743. ; 133, s. 201-213
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Journal article (peer-reviewed)abstract
- In this work, a series of new diketopyrrolopyrrole-based dyes have been synthesized by connecting tetraphenylethene to the diketopyrrolopyrrole core. All the four compounds exhibit good aggregation induced emission property with nonemissive in the solution but strong red fluorescence in the aggregate or solid state. Also, these new dyes exhibit large two-photon absorption cross sections (a), in which the a data measured by the open aperture Z-scan technique are determined to be 150, 300, 1140 and 1016 GM for four dyes, respectively. In addition, compound with stilbene and four tetraphenylethene units (DPP-TPE-3) was used as the luminogen and encapsulated into nanoparticles for cell imaging and two-photon excited fluorescence blood vessels imaging. The result indicates that it can be used as the effective fluorescence probe for bioimaging and has great potential for bioapplications. (C) 2016 Elsevier Ltd. All rights reserved.
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Li, Bo, et al.
(author)
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Comprehensive CO detection in flames using femtosecond two-photon laser-induced fluorescence
- 2017
-
In: Optics Express. - 1094-4087. ; 25:21, s. 25809-25818
-
Journal article (peer-reviewed)abstract
- We demonstrate a femtosecond two-photon laser-induced fluorescence (fs-TPLIF) technique for sensitive CO detection, using a 230 nm pulse of 9 µJ and 45 fs. The advantages of fs-TPLIF in excitation of molecular species were analyzed. Spectra of CO fs-TPLIF were recorded in stable laminar flames spatially resolved across the flame front. A hot band (1, n) together with the conventional band (0, n) of the B→A transitions were observed in the burned zone and attributed to the broadband nature of the fs excitation. The CO fs-TPLIF signal recorded across the focal point of the excitation beam shows a relatively flat intensity distribution despite of the steep laser intensity variation, which is beneficial for CO imaging in contrast to nanosecond and picosecond TPLIF. This phenomenon can be explained by photoionization, which over the short pulse duration dominates the population depletion of the excited B state due to the high peak power, but only contributes in total a negligible X state depletion due to the low pulse energy. Single-shot CO fs-TPLIF images in methane/air flames were recorded by imaging the broadband fluorescence. The results indicate that fs-TPLIF is a promising tool for CO imaging in flames.
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| 45. |
- Li, Bo, et al.
(author)
-
Femtosecond laser-induced cyano chemiluminescence in methane-seeded nitrogen gas flows for near-wall velocimetry
- 2018
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In: Journal of Physics D: Applied Physics. - : IOP Publishing. - 0022-3727 .- 1361-6463. ; 51:29
-
Journal article (peer-reviewed)abstract
- We demonstrate a velocimetric technique based on femtosecond laser-induced cyano (CN) chemiluminescence (FLICC). High intensity emission originated from CN(B-X) fluorescence was observed in filaments generated by focusing a femtosecond laser in methane-seeded nitrogen gas flows. The emission is strong and can last for hundreds of microseconds with a proper methane concentration. FLICC was adopted for velocity measurements, and promising results were obtained for near-wall measurements.
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| 46. |
- Li, Bo, et al.
(author)
-
Filamentary anemometry using femtosecond laser-extended electric discharge - FALED
- 2018
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In: Optics Express. - 1094-4087. ; 26:16, s. 21132-21140
-
Journal article (peer-reviewed)abstract
- We demonstrate a non-contact spatiotemporally resolved comprehensive method for gas flow velocity field measurement: Filamentary Anemometry using femtosecond Laser-extended Electric Discharge (FALED). A faint thin plasma channel was generated in ambient air by focusing an 800-nm laser beam of 45 fs, which was used to ignite a pulsed electric discharge between two electrodes separated over 10 mm. The power supplier provided a maximum voltage up to 5 kV and was operated at a burst mode with a current duration of less than 20 ns and a pulse-to-pulse separation of 40 μs. The laser-guided thin filamentary discharge plasma column was blowing up perpendicularly by an air jet placed beneath in-between the two electrodes. Although the discharge pulse was short, the conductivity of the plasma channel was observed to sustain much longer, so that a sequence of discharge filaments was generated as the plasma channel being blown up by the jet flow. The sequential bright thin discharge filaments can be photographed using a household camera to calculate the flow velocity distribution of the jet flow. For a direct comparison, a flow field measurement using FLEET [Michael, Appl. Opt. 50, 5158 (2011)] was also performed. The results indicate that the FALED technique can provide instantaneous nonintrusive flow field velocity measurement with good accuracy.
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| 47. |
- Li, Bo, et al.
(author)
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Methyl Radical Imaging in Methane-Air Flames Using Laser Photofragmentation-Induced Fluorescence
- 2015
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In: Applied Spectroscopy. - : SAGE Publications. - 1943-3530 .- 0003-7028. ; 69:10, s. 1152-1156
-
Journal article (peer-reviewed)abstract
- Imaging detection of methyl radicals has been performed in laminar premixed methane-air flames at atmospheric pressure. A nanosecond Q-switched neodymium-doped yttrium aluminum garnet (Nd : YAG) laser was employed to provide the fifth-harmonic-generated 212.8 nm laser beam. The intense ultraviolet (UV) laser pulse was sent through the flame front to photodissociate The methyl (CH3) radicals in the reaction zone of the flames stabilized on a piloted jet flame burner. The emission spectra from the photodissociated fragments were collected using an imaging spectrometer with the flame-front structure spatially resolved. Combining the spatial and spectral information, we recognized that the emission from the (A-X) methine (CH) transitions located at 431 nm was generated from the CH3 photolysis and could be used to visualize the distribution of CH3 radicals. With proper filtering, the high-power UV laser (around 15 mJ/pulse) provided by the compact Nd : YAG laser makes it possible to visualize CH3 distribution naturally generated in the reaction zone of laminar methane-air premixed flames.
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| 48. |
- Li, Bo, et al.
(author)
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Strategy of interference-free atomic hydrogen detection in flames using femtosecond multi-photon laser-induced fluorescence
- 2017
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In: International Journal of Hydrogen Energy. - : Elsevier BV. - 0360-3199. ; 42:6, s. 3876-3880
-
Journal article (peer-reviewed)abstract
- Hydrogen atoms are key species in combustion of hydrogen/hydrocarbon fuels. Interference-free detection of hydrogen atoms natively generated in flames using femtosecond laser-induced fluorescence (LIF) was investigated employing two colors, i.e., 243 nm and 486 nm, as excitation source: two-photon excitation followed by a relay one-photon excitation. This strategy was compared with another commonly adopted two-photon LIF strategy using 205 nm for excitation. The potential interferences were investigated, and a direct verification method was proposed to prove this strategy be interference-free, and imaging of hydrogen atoms natively generated in methane/air flames was achieved.
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| 49. |
- Li, Chenglei, et al.
(author)
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Room-temperature direct regeneration of spent LiFePO4 cathode using the external short circuit strategy
- 2023
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In: Next Sustainability. - : Elsevier. - 2949-8236.
-
Journal article (peer-reviewed)abstract
- Lithium iron phosphate batteries (LFP), widely used as power sources, are forecasted to reach the terawatt-hour scale, inevitably leading to battery waste and expediating the urgency for effective recycling processes for LFP. The modern recycling methodologies based on material recovery face significant economic, environmental, and energy consumption challenges. This research attempts to resolve these challenges by providing direct cathode regeneration based on the principles of an external short-circuit to replenish lithium lost in the spent cathode with lithiated materials (LiC6, Li metal). Given that most active lithium loss in the cathode is caused by the growth of the solid electrolyte interphase rather than structural damage, restoring the lost lithium can revitalize a spent cathode battery’s electrochemical performance to a near-original state. The lithium loss in LFP cathodes ranging from 20% to 80% was renewed by supplementing lithium. Relithiation of 10Ah commercial LFP spent cathode showed revitalized electrochemical performance. Compared to the modern recycling methods, direct cathode regeneration improves the economic benefits of recycling by 33%, decreases energy consumption by 48%, and reduces carbon emissions by 62%. Direct cathode regeneration provides a scaffold for the next generation of recycling methods to improve recycling efficiency while reducing their environmental footprint.
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| 50. |
- Li, Weiwei, et al.
(author)
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Tailoring side chains of low band gap polymers for high efficiency polymer solar cells
- 2010
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In: Polymer. - : Elsevier Science B.V., Amsterdam.. - 0032-3861 .- 1873-2291. ; 51:14, s. 3031-3038
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Journal article (peer-reviewed)abstract
- High efficiency organic solar cells (OSCs) require conjugated polymers with a low band gap, broad absorption in visible and IR region, high carrier mobility, and relatively high molecular weight as p-type donor materials. Flexible side chains on the rigid polymer backbone are crucial for the solubility of conjugated polymers. In this work, four polymers with the main chain structure of fluorene-thiophene-benzothiadiazole-thiophene and flexible side chains located on fluorene, thiophene, and benzothiadiazole moiety, respectively, have been synthesized by Suzuki-Miyaura-Schluter polycondensation. Photovoltaic device measurements with a device configuration of ITO/polymer:PC71BM blends/LiF/Al show that P1 carrying octyloxy chains on benzothiadiazole rings gives the best performance, with a power conversion efficiency of 3.1%.
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