| 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. |
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| 4. |
- 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
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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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| 5. |
- He, Shu-Lan, et al.
(author)
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Mitochondrial-related gene expression profiles suggest an important role of PGC-1alpha in the compensatory mechanism of endemic dilated cardiomyopathy.
- 2013
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In: Experimental Cell Research. - : Elsevier. - 0014-4827 .- 1090-2422. ; 319:17, s. 2604-2616
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Journal article (peer-reviewed)abstract
- Keshan disease (KD) is an endemic dilated cardiomyopathy with unclear etiology. In this study, we compared mitochondrial-related gene expression profiles of peripheral blood mononuclear cells (PBMCs) derived from 16 KD patients and 16 normal controls in KD areas. Total RNA was isolated, amplified, labeled and hybridized to Agilent human 4 × 44k whole genome microarrays. Mitochondrial-related genes were screened out by the Third-Generation Human Mitochondria-Focused cDNA Microarray (hMitChip3). Quantitative real-time PCR, immunohistochemical and biochemical parameters related mitochondrial metabolism were conducted to validate our microarray results. In KD samples, 34 up-regulated genes (ratios ≥ 2.0) were detected by significance analysis of microarrays and ingenuity systems pathway analysis (IPA). The highest ranked molecular and cellular functions of the differentially regulated genes were closely related to amino acid metabolism, free radical scavenging, carbohydrate metabolism, and energy production. Using IPA, 40 significant pathways and four significant networks, involved mainly in apoptosis, mitochondrion dysfunction, and nuclear receptor signaling were identified. Based on our results, we suggest that PGC-1alpha regulated energy metabolism and anti-apoptosis might play an important role in the compensatory mechanism of KD. Our results may lead to the identification of potential diagnostic biomarkers for KD in PBMCs, and may help to understand the pathogenesis of KD.
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| 6. |
- Jiang, Shuang, et al.
(author)
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Shear banding-induced ⟨c + a⟩ slip enables unprecedented strength-ductility combination of laminated metallic composites
- 2022
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In: Journal of Materials Science & Technology. - Shenyang, China : Elsevier. - 1005-0302. ; 110, s. 260-268
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Journal article (peer-reviewed)abstract
- Shear bands in metallic materials have been reported to be catastrophic because they normally lead to non-uniform plastic deformation. Ductility of laminated metallic composites deteriorates with increasing processing strain, particularly for those having hexagonal-close-packed (hcp) constituents due to inadequate slip systems and consequently prominent shear banding. Here, we propose a design strategy that counterintuitively tolerates the bands with localized strains, i.e. the shear banded laminar (SBL) structure, which promotes ⟨c + a⟩ dislocation activation in hcp metals and renders unprecedented strengthductility combination in hcp-metal-based composites fabricated by accumulative roll bonding (ARB). The SBL structure is characterized with one soft hcp metal constrained by adjacent hard metal in which dislocations have been accumulated near the bimetal interfaces. High-energy X-ray diffraction astonishingly reveals that more than 90% of dislocations are non-basal in Ti layers of the SBL Ti/Nb composite processed by eight ARB cycles. Moreover, ⟨c + a⟩ dislocations occupy a high fraction of ∼30%, promoting further ⟨c + a⟩ cross slip. The unique stress field tailored by both shear banding and heterophase interface-mediated deformation accommodation triggers important ⟨c + a⟩ slip. This SBL design is of significance for developing hcp-based laminates and other heterostructured materials with high performances.
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| 7. |
- Jin, Ying-Hui, et al.
(author)
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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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In: Military Medical Research. - : Springer Science and Business Media LLC. - 2054-9369. ; 7:1
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Journal article (peer-reviewed)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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| 8. |
- 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
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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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| 9. |
- 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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| 10. |
- Lin, Weili, et al.
(author)
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A superluminous supernova lightened by collisions with pulsational pair-instability shells
- 2023
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In: Nature Astronomy. - 2397-3366. ; 7:7, s. 779-789
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Journal article (peer-reviewed)abstract
- Superluminous supernovae are among the most energetic stellar explosions in the Universe, but their energy sources remain an open question. Here we present long-term observations of one of the closest examples of the hydrogen-poor superluminous supernovae subclass SLSNe-I, supernova SN 2017egm, revealing the most complicated known luminosity evolution of SLSNe-I. Three distinct post-peak bumps were recorded in its light curve collected at about 100–350 days after maximum brightness, challenging current popular power models such as magnetar, fallback accretion, and interaction between ejecta and a circumstellar shell. However, the complex light curve can be well modelled by successive interactions with multiple circumstellar shells with a total mass of about 6.8–7.7 M⊙. In this scenario, large energy deposition from interaction-induced reverse shocks results in ionization of neutral oxygen in the supernova ejecta and hence a much lower nebular-phase line ratio of [O I] λ6,300/([Ca II] + [O II]) λ7,300 (~0.2) compared with that derived for other superluminous and normal stripped-envelope supernovae. The pre-existing multiple shells indicate that the progenitor of SN 2017egm experienced pulsational mass ejections triggered by pair instability within 2 years before explosion, in robust agreement with theoretical predictions for a pre-pulsation helium-core mass of 48–51 M⊙.
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| 11. |
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| 12. |
- Tang, Ting-Ting, et al.
(author)
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Impaired thymic export and apoptosis contribute to regulatory T-cell defects in patients with chronic heart failure.
- 2011
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In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203 .- 1932-6203. ; 6:9, s. e24272-
-
Journal article (peer-reviewed)abstract
- Animal studies suggest that regulatory T (T(reg)) cells play a beneficial role in ventricular remodeling and our previous data have demonstrated defects of T(reg) cells in patients with chronic heart failure (CHF). However, the mechanisms behind T(reg-)cell defects remained unknown. We here sought to elucidate the mechanism of T(reg-)cell defects in CHF patients.
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| 13. |
- Zhu, Zhen-Long, et al.
(author)
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Cytoplasmic expression of p33(ING1b) is correlated with tumorigenesis and progression of human esophageal squamous cell carcinoma.
- 2013
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In: Oncology letters. - : Spandidos Publications. - 1792-1074 .- 1792-1082. ; 5:1, s. 161-166
-
Journal article (peer-reviewed)abstract
- p33(ING1b), a newly discovered candidate tumor suppressor gene and a nuclear protein, belongs to the inhibitor of growth gene family. Previous studies have shown that p33(ING1b) is involved in the restriction of cell growth and proliferation, apoptosis, tumor anchorage-independent growth, cellular senescence, maintenance of genomic stability and modulation of cell cycle checkpoints. Loss of nuclear p33(ING1b) has been observed in melanoma, seminoma, papillary thyroid carcinoma, oral squamous cell carcinoma, breast ductal cancer and acute lymphoblastic leukemia. Inactivation and/or decreased expression of p33(ING1b) have been reported in various types of cancer, including head and neck squamous cell, breast, lung, stomach, blood and brain malignancies. Since little is known about the clinicopathological significance of p33(ING1b) in esophageal squamous cell carcinoma (ESCC), this study aimed to investigate the association of p33(ING1b) expression with clinicopathological variables and particularly interesting new cysteine-histidine rich protein (PINCH) in patients with ESCC. p33(ING1b) expression was examined by immunohistochemistry in 20 normal esophageal mucosa and in 64 ESCC specimens. The results revealed that the positive expression of p33(ING1b) protein in normal squamous cells was localized in the nucleus alone and the positive rate was 95%, while in ESCCs, the positive expression was mainly in the cytoplasm, together with nuclear expression, and the positive rate was 36% (P<0.0001). Furthermore, the cases with lymph node metastasis showed a higher frequency of positive cytoplasmic expression than those without metastasis (P=0.001). The cytoplasmic expression of p33(ING1b) was positively related to PINCH expression (P<0.0001) in ESCC, and the cases positive for both proteins had a high lymph node metastasis rate (P=0.001). In conclusion, p33(ING1b) cellular compartmental shift from the nucleus to the cytoplasm may cause loss of normal cellular function and play a central role in the tumorigenesis and metastasis of ESCC.
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| 14. |
- Zhu, Zhen-Long, et al.
(author)
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Overexpression of FXYD-3 is involved in the tumorigenesis and development of esophageal squamous cell carcinoma
- 2013
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In: Disease Markers. - : IOS Press. - 0278-0240 .- 1875-8630. ; 35:3, s. 195-202
-
Journal article (peer-reviewed)abstract
- Objective: To investigate the association of FXYD-3 expression with clinicopathological variables and PINCH in patients with ESCC.Patients and methods: Expression of FXYD-3 protein was immunohistochemically examined in normal esophageal mucous (n = 20) and ESCC (n = 64). Results: Expression of FXYD-3 in the cytoplasm markedly increased from normal esophageal epithelial cells to primary ESCC ( p = 0.001). The expression of FXYD-3 was correlated with TNM stages and depth of tumour invasion. Furthermore, the cases with lymph node metastasis tended to show a higher frequency of positive expression than those without metastasis ( p = 0.086), and FXYD-3 expression tended to be positively related to the expression of PINCH (p = 0.063). Moreover, the cases positive for both proteins had the highest frequency of lymph node metastasis (p = 0.001). However, FXYD-3 expression was not correlated with patient,s gender (p = 0.847), age (p = 0.876), tumour location (p = 0.279), size (p = 0.771) , grade of differentiation (p = 0.279), and survival (p = 0.113).Conclusion: overexpression of FXYD-3 in the cytoplasm may play an important role in the tumourigenesis and development in the human ESCC, particularly in combination with PINCH expression.
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| 15. |
- Zhu, Zhen-Long, et al.
(author)
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PINCH expression and its clinicopathological significance in gastric adenocarcinoma
- 2012
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In: Disease Markers. - : IOS Press. - 0278-0240 .- 1875-8630. ; 33:4, s. 171-178
-
Journal article (peer-reviewed)abstract
- Objective: Particularly interesting new cysteine-histidine rich protein (PINCH) is an important component of the local adhesion complexes and upregulated in several types of malignancies, and involved in the incidence and development of tumours. PINCH expression is also independently correlated with poorer survival in patients with colorectal cancer. However, there is no study of PINCH in gastric cancer, therefore, the aim of this project was to investigate PINCH expression and its clinicopathological significance in gastric adenocarcinoma. less thanbrgreater than less thanbrgreater thanPatients and methods: PINCH expression was immunohistochemically examined in normal gastric mucous (n = 30) and gastric adenocarcinoma (n = 73), from gastric cancer patients. less thanbrgreater than less thanbrgreater thanResults: PINCH expression in the associated-stroma of gastric cancers was heterogeneous, and its positive rate (75%) was higher than that of normal gastric mucosa (43%, X-2 = 9.711, p = 0.002). The stronger staining was observed at the invasive edge of tumour when compared to the inner area of tumour. The rate of positive PINCH (88%) in the cases with lymph node metastasis was higher than that (52%) in the cases without metastasis (X-2 = 11.151, p = 0.001). PINCH expression was not correlated with patients gender, age, tumour size, differentiation and invasion depth (p andgt; 0.05). less thanbrgreater than less thanbrgreater thanConclusion: PINCH protein might play an important role in the tumourigenesis and metastasis of gastric adenocarcinoma.
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| 16. |
-
- 2019
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Journal article (peer-reviewed)
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| 17. |
- Abdoullaye, Doukary, et al.
(author)
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Permanent genetic resources added to molecular ecology resources database 1 August 2009 - 30 September 2009
- 2010
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In: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 10:1, s. 232-236
-
Journal article (peer-reviewed)abstract
- This article documents the addition of 238 microsatellite marker loci and 72 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Adelges tsugae, Artemisia tridentata, Astroides calycularis, Azorella selago, Botryllus schlosseri, Botrylloides violaceus, Cardiocrinum cordatum var. glehnii, Campylopterus curvipennis, Colocasia esculenta, Cynomys ludovicianus, Cynomys leucurus, Cynomys gunnisoni, Epinephelus coioides, Eunicella singularis, Gammarus pulex, Homoeosoma nebulella, Hyla squirella, Lateolabrax japonicus, Mastomys erythroleucus, Pararge aegeria, Pardosa sierra, Phoenicopterus ruber ruber and Silene latifolia. These loci were cross-tested on the following species: Adelges abietis, Adelges cooleyi, Adelges piceae, Pineus pini, Pineus strobi, Tubastrea micrantha, three other Tubastrea species, Botrylloides fuscus, Botrylloides simodensis, Campylopterus hemileucurus, Campylopterus rufus, Campylopterus largipennis, Campylopterus villaviscensio, Phaethornis longuemareus, Florisuga mellivora, Lampornis amethystinus, Amazilia cyanocephala, Archilochus colubris, Epinephelus lanceolatus, Epinephelus fuscoguttatus, Symbiodinium temperate-A clade, Gammarus fossarum, Gammarus roeselii, Dikerogammarus villosus and Limnomysis benedeni. This article also documents the addition of 72 sequencing primer pairs and 52 allele specific primers for Neophocaena phocaenoides.
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| 18. |
- Algaba, Juan-Carlos, et al.
(author)
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Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
- 2021
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In: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 911:1
-
Research review (peer-reviewed)abstract
- In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M o˙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87's spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded.
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| 19. |
- Chen, Shao-Chun, et al.
(author)
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Prevalence and Molecular Epidemiological Typing of Penicillinase-Producing Neisseria gonorrhoeae and Their bla(TEM-135) Gene Variants in Nanjing, China
- 2013
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In: Sexually Transmitted Diseases. - 0148-5717 .- 1537-4521. ; 40:11, s. 872-876
-
Journal article (peer-reviewed)abstract
- Background: This study aimed to investigate the prevalence of penicillinase-producing Neisseria gonorrhoeae (PPNG) and their bla(TEM-135) gene variant in 2007 and 2012 in Nanjing, China. In addition, molecular epidemiological typing of all isolates was performed to elucidate the genetic relationships of the PPNG strains. Methods: A total of 199 and 77 N. gonorrhoeae isolates were collected at the National Center for STD Control in 2007 and 2012, respectively. Nitrocefin tests were performed to identify PPNG. Mismatch amplification mutation assay was used to identify bla(TEM-135). All isolates were genotyped using N. gonorrhoeae multiantigen sequence typing (NG-MAST), and additionally, porB-based phylogenetic analysis was performed for the PPNG isolates. Results: The total prevalence of PPNG isolates was 41% (114/276) and 58% (66/114) of these PPNG isolates possessed bla(TEM-135). In 2007, 45% (90/199) produced beta-lactamase, and of those PPNG, 58% (52/90) possessed bla(TEM-135). In 2012, 31% (24/77) were PPNG, and 58% (14/24) of those isolates contained bla(TEM-135). There were 162 NG-MAST STs among the 276 isolates, and 89 of those were novel STs. A strong association between specific NG-MAST STs and bla(TEM-135) was found, and the porB-based phylogenetic analysis showed a distant evolutionary relationship between isolates in 2007 and isolates in 2012. Conclusions: A high prevalence of PPNG and bla(TEM-135) was found in Nanjing, China. bla(TEM-135) might be a precursor in the evolution into an extended-spectrum beta-lactamase that can degrade ceftriaxone, which stresses the need to continuously monitor PPNG, bla(TEM-135), and additional evolving bla(TEM) gene variants.
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| 20. |
- Chen, Yan, et al.
(author)
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Silver-Promoted (4+1) Annulation of Isocyanoacetates with Alkylpyridinium Salts : Divergent Regioselective Synthesis of 1,2-Disubstituted Indolizines
- 2021
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In: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 23:19, s. 7555-7560
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Journal article (peer-reviewed)abstract
- An unprecedented silver-promoted regioselective (4 + 1) annulation of isocyanoacetates with pyridinium salts is reported. The established protocol provides controlled, facile, and modular access to a range of synthetically useful N-fused heterocyclic scaffolds containing indolizines, pyrrolo[1,2-a]quinolines, pyrrolo[2,1-a]isoquinolines, and 1H-imidazo[4,5-a]indolizin-2(3H)-ones. A mechanistic pathway involving nucleophilic addition/protonation/elimination/cydoisomerization is proposed.
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| 21. |
- Chen, Zhibin, et al.
(author)
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Summary of the 3rd International Workshop on Gas-Dynamic Trap based Fusion Neutron Source (GDT-FNS)
- 2022
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In: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 62:6
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Journal article (peer-reviewed)abstract
- The 3rd International Workshop on Gas-Dynamic Trap-based Fusion Neutron Source (GDT-FNS) was held through the hybrid mode on 13-14 September 2021 in Hefei, China, jointly organized by the Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Sciences (CAS), and the Budker Institute of Nuclear Physics (BINP), Russian Academy of Sciences (RAS). It followed the 1st GDT-FNS Workshop held in November 2018 in Hefei, China, and the 2nd taking place in November 2019 in Novosibirsk, Russian Federation. With the financial support from CAS and China Association for Science and Technology (CAST), this workshop was attended by more than 80 participants representing 20 institutes and universities from seven countries, with oral presentations broadcast via the Zoom conferencing system. Twenty-two presentations were made with topics covering design and key technologies, simulation and experiments, steady-state operation, status of the ALIANCE project, multi applications of neutron sources, and other concepts (Tokamaks, Mirrors, FRC, Plasma Focus, etc). The workshop consensus was made including the establishment of the ALIANCE International Working Group. The next GDT-FNS workshop is planned to be held in May 2022 in Novosibirsk.
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| 22. |
- Deng, Huan, et al.
(author)
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Altered Expression of the Hedgehog Pathway Proteins BMP2, BMP4, SHH, and IHH Involved in Knee Cartilage Damage of Patients With Osteoarthritis and Kashin-Beck Disease
- 2022
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In: Cartilage. - : Sage Publications. - 1947-6035 .- 1947-6043. ; 13:1
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To investigate the expression of Hedgehog (HH) signaling pathway proteins in knee articular cartilage from Kashin-Beck disease (KBD) and osteoarthritis (OA) patients.METHODS: Knee articular cartilage samples were collected from normal (N), OA, and KBD adults (aged 38-60 years) and divided into 3 groups with 6 subjects in each group. The localization of the HH pathway proteins bone morphogenetic protein 2 (BMP2), bone morphogenetic protein 4 (BMP4), Sonic hedgehog (SHH), and Indian hedgehog (IHH) was observed with the microscope after immunohistochemical (IHC) staining. Positive staining cell rates of each proteins were compared.RESULTS: The strongest stainings of all proteins were observed in the middle zones of all 3 groups. The positive staining rates of BMP4 and IHH were significantly lower in the OA and KBD groups than those in the N group in all 3 zones. The positive staining rates of BMP2 and SHH tend to be lower in the OA and KBD groups than those in the N group in the deep zone, while higher in the OA and KBD groups than those in the N group in superficial and middle zones.CONCLUSIONS: Altered expression of the HH pathway proteins BMP2, BMP4, SHH, and IHH was found in OA and KBD articular cartilage. There seemed to be a compensatory effect between SHH and IHH in cartilage damage. Further studies on the pathogenesis of OA and KBD may be carried out from these aspects in the future.
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| 23. |
- Deng, Yucheng, et al.
(author)
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A numerical study on the levitation system for droplet preparation in a fuel-coolant interaction experiment
- 2023
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In: Progress in nuclear energy (New series). - : Elsevier BV. - 0149-1970 .- 1878-4224. ; 159
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Journal article (peer-reviewed)abstract
- The MISTEE facility at KTH was designed to investigate the process and phenomena of a molten droplet falling into a water pool that may be encountered in fuel-coolant interactions (FCI) during a severe accident of light water reactors. An aerodynamic levitation mechanism is proposed to hold the molten droplet during its preparation (melting and heating up to a prescribed temperature) in an induction furnace. The crucible is flushed with argon through an injection nozzle at the bottom to prevent the droplet from falling out of the crucible. A numerical simulation of the aerodynamic levitation system is performed in the present study with the objective of determining and optimizing the design. The problem was simplified as an isothermal two-phase flow in an axisymmetric geometry. The simulation is realized through ANSYS Fluent v17 platform, which employs the VOF method to track interfaces between two phases and the SST k-omega model to describe turbulence flow of argon gas. The numerical model is validated against tests performed in the MISTEE facility after mesh sensitivity study. It is then applied to investigate the impacts of various parameters on the facility levitation capability and the droplet stability. According to the simulation results, stable molten droplets can be obtained in the designed experimental setup. The simulation also provides the appropriate values of argon inlet velocity and sample mass at which a stable droplet can be obtained inside the crucible before its discharge. Either higher or lower inlet velocity will destabilize the formation of the droplet. Considering the temperature-dependent melt properties, both surface tension and viscosity affect the movement and deformation of the molten droplet. The wettability of melt on the crucible wall is critical to droplet formation, and it is found that a poor wettability can ensure the levitation of droplet.
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| 24. |
- Deng, Yucheng, et al.
(author)
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An experimental study on droplet quench and steam explosion in boric acid solutions
- 2023
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In: Progress in nuclear energy (New series). - : Elsevier BV. - 0149-1970 .- 1878-4224. ; 166
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Journal article (peer-reviewed)abstract
- Boric acid (H3BO3) is widely adopted as an additive in the coolant of light water reactors for reactivity control, but its effect on fuel coolant interactions (FCI) during severe accidents (especially on steam explosion) was rarely investigated. To examine the effect of the boric acid additive in coolant on steam explosion, a series of molten droplet-coolant interaction tests using H3BO3 solutions (with concentration ranging from 0-3.2% by weight) is carried out in the present study. The characteristics of melt-coolant interactions are the occurrence probability of typical phenomena (no fragmentation, minor fragmentation, or spontaneous steam explosion), lateral deformation ratio, quench depth, pressure impulse and debris particle size distribution. The statistical data of such characteristics are obtained through repeating 20 runs of the same test category. The experimental results show that the H3BO3 addition in coolant has various impacts on the above-mentioned characteristics of melt-coolant interactions, depending on the H3BO3 concentration. In particular, the probability of steam explosion sightly decreases as the H3BO3 concentration increases from zero to 1.2 wt.%, but significantly increases as the H3BO3 concentration further increases to 3.2 wt.% trough 2.2 wt.%. Namely, the inhibiting effect of boric acid on steam explosion is diminishing with increasing H3BO3 concentration beyond 1.2 wt.%. It is also found that both melt and coolant temperatures are crucial parameters impacting the likelihood and energetics of steam explosion.
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| 25. |
- Deng, Yucheng, et al.
(author)
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An Experimental study on steam explosion of multiple droplets in different chemical solutions
- 2024
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In: International Journal of Heat and Mass Transfer. - : Elsevier BV. - 0017-9310 .- 1879-2189. ; 226
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Journal article (peer-reviewed)abstract
- Motivated by the interest in steam explosion in chemical solutions and seawater, a series of tests were carried out in the MISTEE facility at KTH to investigate steam explosion characteristics as multiple molten droplets of tin were falling through a coolant pool containing deionized water, boric acid solution, neutral solution of boric acid and sodium phosphate, and seawater, separately. The experimental results revealed distinct and complex characteristics of steam explosion of multiple droplets, which were not observed in previous single-droplet steam explosion experiments. The tin melt samples of 5 g and 20 g were employed to formulate different numbers of multiple droplets. In the test with 5 g melt, steam explosion was more energetic at a deeper explosion location − a similar trend found in the single-droplet steam explosion test with 1 g melt. However, the test of 20 g melt did not show a clear trend in a wide range of explosion depth. The peak pressure and impulse increased with increasing mass of melt sample. The steam explosion occurred more closely to the coolant pool surfaces in the seawater and chemical solutions than in deionized water. Steam explosion intensity was significantly reduced in a neutral solution containing 1.2 wt.% boric acid and sodium phosphate. The influence of the chemical solutions on steam explosion was diminishing in the tests with multiple droplets.
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