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1. chinaXiv:202203.00038 [pdf]

Assessment of river basin habitat quality and its relationship with disturbance factors: A case study of the Tarim River Basin in Northwest China

HE Bing; CHANG Jianxia; GUO Aijun; WANG Yimin; WANG Yan; LI Zhehao
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology

The status of regional biodiversity is determined by habitat quality. The effective assessment of habitat quality can help balance the relationship between economic development and biodiversity conservation. Therefore, this study used the InVEST model to conduct a dynamic evaluation of the spatial and temporal changes in habitat quality of the Tarim River Basin in southern Xinjiang Uygur Autonomous Region of China by calculating the degradation degree levels for habitat types that were caused by threat factors from 1990 to 2018 (represented by four periods of 1990, 2000, 2010 and 2018). Specifically, we used spatial autocorrelation analysis and Getis-Ord G* i analysis to divide the study area into three heterogeneous units in terms of habitat quality: cold spot areas, hot spot areas and random areas. Hemeroby index, population density, gross domestic product (GDP), altitude and distance from water source (DWS) were then chosen as the main disturbance factors. Linear correlation and spatial regression models were subsequently used to analyze the influences of disturbance factors on habitat quality. The results demonstrated that the overall level of habitat quality in the TRB was poor, showing a continuous degradation state. The intensity of the negative correlation between habitat quality and Hemeroby index was proven to be strongest in cold spot areas, hot spot areas and random areas. The spatial lag model (SLM) was better suited to spatial regression analysis due to the spatial dependence of habitat quality and disturbance factors in heterogeneous units. By analyzing the model, Hemeroby index was found to have the greatest impact on habitat quality in the studied four periods (1990, 2000, 2010 and 2018). The research results have potential guiding significance for the formulation of reasonable management policies in the TRB as well as other river basins in arid areas.

submitted time 2022-03-15 Cooperative journals:《Journal of Arid Land》 Hits1612Downloads294 Comment 0

2. chinaXiv:202201.00029 [pdf]

High RF power tests of the first 1.3 GHz fundamental power coupler prototypes for the SHINE project

Ma, Zhen-Yu ; Zhao, Shen-Jie; Liu, Xu-Ming; Yu, Yue-Chao; Jiang, Hong-Ru; Zheng, Xiang; Chang, Qiang; Zhang, Zi-Gang; Xu, Kai; Wang, Yan; Zhao, Yu-Bin; Hou, Hong-Tao
Subjects: Nuclear Science and Technology >> Particle Accelerator

The Shanghai High Repetition Rate XFEL and Extreme Light Facility (SHINE) project will use 600 1.3 GHz fundamental power couplers, which are modified based on TTF-III power couplers, for continuous wave operation with input power up to approximately 7 kW. The first batch of 20 sets of 1.3 GHz coupler prototypes were fabricated from three domestic manufacturers for the SHINE project. To better characterize the radio frequency conditioning phenomena for validating the performance of power couplers, a room temperature test stand was designed, constructed, and commissioned for the SHINE 1.3 GHz power couplers. In addition, a horizontal test cryostat was built to test the 1.3 GHz superconducting cavities, fundamental power couplers, tuners, and other components as a set. The results of these tests indicate that the 1.3 GHz couplers are capable of handling up to 14 kW continuous waves. Herein, the main aspects of the radio frequency design and construction of the test stand, along with the test results of the high-power conditioning of the 1.3 GHz couplers, are described.

submitted time 2021-12-31 Cooperative journals:《Nuclear Science and Techniques》 Hits817Downloads135 Comment 0

3. chinaXiv:201712.02140 [pdf]

Equol protects PC12 neuronal cells against hypoxia/reoxygenation injury in vitro by reducing reactive oxygen species production

YU Wei; DENG Xiuling; MAZhen; WANG Yan
Subjects: Medicine, Pharmacy >> Preclinical Medicine

Objective Both of gp91 phox (an isoform of nicotinamide adenine dinucleotide phosphate-reduced oxidases) and Src (a non-receptor protein tyrosine kinase) play a prominent role in mediating hypoxia/reoxygenation injury of neurons. The present study was designed to investigate the neuroprotective effect of equol, a predominant active metabolite of daidzein, against hypoxia/reoxygenation injury in rat pheochromocytoma cell line (PC12) and explore the underlying mechanisms. Methods PC12 cells exposed to hypoxia/reoxygenation injury were examined for reactive oxygen species (ROS) using dihydroethidium and 2', 7'-dichlorofluorescein diacetate and analyzed for changes in lactate dehydrogenase (LDH) activity and malondialdehyde (MDA)content. The expression levels of gp91 phox and phosphorylated Src-Tyr416 (p-Src) were measured using Western blotting. Results Equol dose-dependently restored the cell viability and decreased LDH activity and MDA content in culture medium of PC12 cells exposed to hypoxia/reoxygenation. Pretreatment of the cells with 10 -5 and 10 -6 mol/L equol inhibited hypoxia/reoxygenation-induced increase of ROS. PC12 cells treated with equol prior to hypoxia/reoxygenation injury showed significant enhancement of the protein levels of gp91 phox and p-Src. Conclusion Equol confers neuroprotection against hypoxia/reoxygenation injury in PC12 cells by inhibiting the generation of ROS very likely as a result of down-regulation of gp91 phox and inhibition of Src phosphorylation.

submitted time 2017-12-27 Cooperative journals:《南方医科大学学报》 Hits998Downloads585 Comment 0

4. chinaXiv:201711.02422 [pdf]

Fumarylacetoacetate?Hydrolase?Knock-out?Rabbit?Model?for?Hereditary?Tyrosinemia?Type?1

Li, L?(Li, Li); Zhang, QJ?(Zhang, Quanjun); Yang, HQ?(Yang, Huaqiang); Zou, QJ?(Zou, Qingjian); Lai, CD?(Lai, Chengdan); Jiang, F?(Jiang, Fei); Zhao, P?(Zhao, Ping); Luo, ZW?(Luo, Zhiwei); Yang, JY?(Yang, Jiayin); Chen, Q?(Chen, Qian); Wang, Y?(Wang, Yan); Newsome, PN?(Newsome, Philip N.); Frampton, J?(Frampton, Jon); Maxwell, PH?(Maxwell, Patrick H.); Li, WJ?(Li, Wenjuan); Chen, SH?(Chen, Shuhan); Wang, DY?(Wang, Dongye); Siu, TS?(Siu, Tak-Shing); Tam, S?(Tam, Sidney); Tse, HF?(Tse, Hung-Fat)
Subjects: Biology >> Ecology

From the (a)CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China, and Guangzhou Medical University, Guangzhou 511436, China, (b)CAS Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China, (c)Laboratory of RNA, Chromatin, and Human Disease, CAS Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China, (d)Cardiology Division, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong SAR, China, (e)Hong Kong-Guangdong Stem Cell and Regenerative Medicine Research Centre, The University of Hong Kong and Guangzhou Institutes of Biomedicine and Health, Hong Kong SAR, China, (f)Department of Ophthalmology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China, (g)State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Guangdong Provincial Research Center?for?Liver Fibrosis, Department of Infectious Diseases and Hepatology Unit, Nanfang Hospital and (h)Biomedical Research Center, Southern Medical University, Guangzhou 510515, China, (i)Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, (j)National Institute?for?Health Research (NIHR) Birmingham Liver Biomedical Research Unit and Centre?for?Liver Research, and (k)Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, United Kingdom, (l)Cambridge Institute?for?Medical Research, Wellcome Trust/Medical Research Council (MRC) Building, Cambridge CB2 0XY, United Kingdom, mDepartment of Clinical Biochemistry Unit, Queen Mary Hospital, Hong Kong SAR, China, (n)Department of Medicine, University of Hong Kong-Shenzhen Hospital, Shenzhen 518053, Guangdong, China, and (o)Laboratory of Metabolism and Cell Fate, CAS Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, Guangdong, China

submitted time 2017-11-17 Hits1667Downloads947 Comment 0

5. chinaXiv:201710.00003 [pdf]

Development and applications of paleontological computed tomography

WANG Yan-Fang; WEI Cun-Feng; QUE Jie-Min; ZHANG Wen-Ding; SUN Cui-Li; SHU Yan-Feng; HOU Ye-Mao; ZHANG Jiu-Chang; SHI Rong-Jian; WEI Long
Subjects: Geosciences >> Geology

The traditional serial grinding method used to investigate the internal structure of fossils cannot be readily applied to valuable fossil specimens due to its destructive and time-consuming nature. Computed tomography (CT) is an ideal non-destructive technique for investigating the internal structure of fossils, in which thousands of serial images are obtained and used to produce an accurate reconstruction of the internal morphology. This paper reviews the design, development and applications of the first CT system in China dedicated exclusively to scanning fossils. The 225 kV three-dimensional (3D) fossil micro-CT (225-3D-μCT) is capable of high-resolution volumetric imaging, with a resolution up to 5 μm, and can accommodate specimens measuring up to 100 mm in diameter and 100 mm in length. The 450 kV ordinary fossil CT (450-TY-ICT) can produce high signal-to-noise ratio (SNR) images of specimens ranging up to 800 mm in diameter and 1000 mm in length, with a resolution up to 200 μm. Two paleontological CT facilities represent a high-performance platform offering the functional diversity needed to meet the demands of studying fossils at a variety of different scales. The two machines have become indispensable for paleontological research in China.

submitted time 2017-10-09 Cooperative journals:《古脊椎动物学报》 Hits4368Downloads2043 Comment 0

6. chinaXiv:201708.00328 [pdf]

Taxonomic reassessment and phylogenetic test of Asiatosuchus nanlingensis Young, 1964 and Eoalligator chunyii Young, 1964

WU Xiao-Chun; LI Chun; WANG Yan-Yin
Subjects: Geosciences >> Geology

The present paper revalidated Asiatosuchus nanlingensis Young, 1964 and Eoalligator chunyii Young, 1964 in taxonomy based on a detailed comparative study on those relevant specimens. New information derived from this study revealed that A. nanlingensis and E. chunyii were truly distinguishable from each other and therefore, diagnosis was further revised for each of them. A. nanlingensis is large, with a moderately long or a very elongate snout, and characterised mainly by the combination of the following characters such as: the quadrate with a lateral condyle much larger than the medial one, the surangular pinched off before reaching the end of the retroarticular process, the dental margins (at least the posterior portion) of the jaws nearly straight, and the presence of a fossa/sulcus on the lateral surface of the surangular lateral to the mandibular fossa. E. chunyii is a median-sized, short-snouted animal and characterised mainly by the combination of the following characters such as: the condyles of the quadrate similar in size, the dental margins of the jaws strongly concavo-convex, the dentary symphyses very short, the splenial not entering the mandibular symphysis, and the presence of a fossa/sulcus on the lateral surface of the surangular lateral to the mandibular fossa. With new information derived from this study, the phylogenetic relationships of A. nanlingensis and E. chunyii were tested, which did not support the view that the two species formed a monophyletic clade and opposed that E. chunyii could be considered as the synonym of A. nanlingensis. 根据对有关标本的详细对比研究,重新评估了南岭亚洲鳄(Asiatosuchus nanlingensis Young, 1964)和存义始猛鳄(Eoalligator chunyii Young, 1964)的分类。获得的新信息表明这两种是可以彼此区分的,因此对它们各自的鉴定特征进行了进一步修订。南岭亚洲鳄是个大型种类,它很可能具有中等或很长的吻部(眶前段), 主要由以下一些特征组合界定:方骨外髁比内髁大很多,上隅骨在反关节突近端尖灭,上、下颌齿缘(至少后段)几近平直,以及在下颌关节窝外侧上隅骨表面具一凹或纵沟。存义始猛鳄是个中型种类,主要可以由下列特征组合界定:方骨内、外关节髁大小几近相当,上、下颌齿缘强烈凹凸不平,齿骨联合很短,夹板骨不进入下颌联合,以及在下颌关节窝外侧上隅骨表面具一凹或纵沟。根据新的信息对南岭亚洲鳄和存义始猛鳄原来的系统关系进行了检验,所得结果不支持南岭亚洲鳄和存义始猛鳄可以形成一单系分支及反对后者是前者的同物异名。虽然本文研究表明南岭亚洲鳄可以和其他种类区分,但是在系统关系上却不能和亚洲鳄典型种(葛氏亚洲鳄Asiatosuchus grangeri)归于同一支系,如此应该为其建立一属。然而,鉴于南岭亚洲鳄标本太不完整,在没有新的、更完整的标本发现之前,本文仍沿用其原名,如德国亚洲鳄(Asiatosuchus germanicus)一样,后者也不和亚洲鳄典型种归于同一支系。

submitted time 2017-08-24 Cooperative journals:《古脊椎动物学报》 Hits2756Downloads1424 Comment 0

7. chinaXiv:201708.00327 [pdf]

High-precision temporal calibration of Middle Triassic vertebrate biostratigraphy: U-Pb zircon constraints for the Sinokannemeyeria Fauna and Yonghesuchus

LIU Jun; Jahandar RAMEZANI; LI Lu; SHANG Qing-Hua; XU Guang-Hui; WANG Yan-Yin; YANG Jia-Sheng
Subjects: Geosciences >> Geology

Tetrapod assemblages provide a useful means for global correlation of the terrestrial Triassic sedimentary deposits, but currently no reliable temporal framework has been achieved for the Middle Triassic tetrapod assemblages. Here we report U-Pb zircon chemical abrasion–thermal ionization mass spectrometry dates for five volcanic ashes interbedded with vertebrate fossils from the Ermaying and Tongchuan formations of China. Our results support a late Anisian age for the Sinokannemeyeria Fauna and an early Ladinian age for Yonghesuchus Fauna. It is now possible, through biostratigraphic correlation, to provide accurate ages to other Middle Triassic successions such as the Upper Cynognathus Assemblage Zone of the Karoo of South Africa, the Eryosuchus fauna of the Donguz Suite of Russia and the Karamayi Formation of Xinjiang, China. The base of Anisian (Lower/Middle Triassic boundary) should lie below the base of the Ermaying Formation in the Ordos Basin. 四足动物组合带是全球陆相三叠系对比的有力手段,但是迄今为止中三叠世的四足动物组合尚没有可靠的时间框架。本文报道了五个采自二马营组和铜川组,与四足动物化石共同产出的火山凝灰岩样品的锆石化学剥蚀-热电离质谱法年龄。结果表明中国肯氏兽动物群时代为安尼期晚期,而永和鳄的时代为拉丁期早期。通过生物地层对比,这一结果还为其他中三叠世的四足动物组合,如南非的犬颌兽带上部、俄罗斯的引鳄动物群以及新疆的克拉玛依组提供了准确的年龄。鄂尔多斯盆地下中三叠统界线应低于二马营组底界。

submitted time 2017-08-24 Cooperative journals:《古脊椎动物学报》 Hits2984Downloads1472 Comment 0

8. chinaXiv:201605.01373 [pdf]

NeuroPep: a comprehensive resource of neuropeptides

Wang, Yan; Wang, Mingxia; Wang, Jian; Xu, Tao; Yin, Sanwen; Jang, Richard; Xue, Zhidong; Jang, Richard; Xu, Tao
Subjects: Biology >> Biophysics

Neuropeptides play a variety of roles in many physiological processes and serve as potential therapeutic targets for the treatment of some nervous-system disorders. In recent years, there has been a tremendous increase in the number of identified neuropeptides. Therefore, we have developed NeuroPep, a comprehensive resource of neuropeptides, which holds 5949 non-redundant neuropeptide entries originating from 493 organisms belonging to 65 neuropeptide families. In NeuroPep, the number of neuropeptides in invertebrates and vertebrates is 3455 and 2406, respectively. It is currently the most complete neuropeptide database. We extracted entries deposited in UniProt, the database (www.neuropeptides.nl) and NeuroPedia, and used text mining methods to retrieve entries from the MEDLINE abstracts and full text articles. All the entries in NeuroPep have been manually checked. 2069 of the 5949 (35%) neuropeptide sequences were collected from the scientific literature. Moreover, NeuroPep contains detailed annotations for each entry, including source organisms, tissue specificity, families, names, post-translational modifications, 3D structures (if available) and literature references. Information derived from these peptide sequences such as amino acid compositions, iso-electric points, molecular weight and other physicochemical properties of peptides are also provided. A quick search feature allows users to search the database with keywords such as sequence, name, family, etc., and an advanced search page helps users to combine queries with logical operators like AND/OR. In addition, user-friendly web tools like browsing, sequence alignment and mapping are also integrated into the NeuroPep database.

submitted time 2016-05-12 Hits2141Downloads1265 Comment 0

9. chinaXiv:201605.01371 [pdf]

Succinylome Analysis Reveals the Involvement of Lysine Succinylation in Metabolism in Pathogenic Mycobacterium tuberculosis

Yang, Mingkun; Wang, Yan; Chen, Ying; Mo, Ran; Ge, Feng; Cheng, Zhongyi; Gu, Jing; Deng, Jiaoyu; Wang, Xude; Bi, Lijun; Chen, Chuangbin
Subjects: Biology >> Biophysics

Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis, remains one of the most prevalent human pathogens and a major cause of mortality worldwide. Metabolic network is a central mediator and defining feature of the pathogenicity of Mtb. Increasing evidence suggests that lysine succinylation dynamically regulates enzymes in carbon metabolism in both bacteria and human cells; however, its extent and function in Mtb remain unexplored. Here, we performed a global succinylome analysis of the virulent Mtb strain H37Rv by using high accuracy nano-LC-MS/MS in combination with the enrichment of succinylated peptides from digested cell lysates and subsequent peptide identification. In total, 1545 lysine succinylation sites on 626 proteins were identified in this pathogen. The identified succinylated proteins are involved in various biological processes and a large proportion of the succinylation sites are present on proteins in the central metabolism pathway. Site-specific mutations showed that succinylation is a negative regulatory modification on the enzymatic activity of acetylCoA synthetase. Molecular dynamics simulations demonstrated that succinylation affects the conformational stability of acetyl-CoA synthetase, which is critical for its enzymatic activity. Further functional studies showed that CobB, a sirtuin-like deacetylase in Mtb, functions as a desuccinylase of acetyl-CoA synthetase in in vitro assays. Together, our findings reveal widespread roles for lysine succinylation in regulating metabolism and diverse processes in Mtb. Our data provide a rich resource for functional analyses of lysine succinylation and facilitate the dissection of metabolic networks in this life-threatening pathogen.

submitted time 2016-05-12 Hits2006Downloads1297 Comment 0

10. chinaXiv:201605.00744 [pdf]

Epithelial microRNA-9a regulates dendrite growth through Fmi-Gq signaling in Drosophila sensory neurons

Wang, Yan; Wang, Huan; Li, Xiaoting; Li, Yan; Wang, Yan; Wang, Huan; Li, Xiaoting;
Subjects: Biology >> Biophysics >> Developmental Biology

microRNA-9 (miR-9) is highly expressed in the nervous system across species and plays essential roles in neurogenesis and axon growth; however, little is known about the mechanisms that link miR-9 with dendrite growth. Using an in vivo model of Drosophila class I dendrite arborization (da) neurons, we show that miR-9a, a Drosophila homolog of mammalian miR-9, downregulates the cadherin protein Flamingo (Fmi) thereby attenuating dendrite development in a non-cell autonomous manner. In miR-9a knockout mutants, the dendrite length of a sensory neuron ddaE was significantly increased. Intriguingly, miR-9a is specifically expressed in epithelial cells but not in neurons, thus the expression of epithelial but not neuronal Fmi is greatly elevated in miR-9a mutants. In contrast, overexpression of Fmi in the neuron resulted in a reduction in dendrite growth, suggesting that neuronal Fmi plays a suppressive role in dendrite growth, and that increased epithelial Fmi might promote dendrite growth by competitively binding to neuronal Fmi. Fmi has been proposed as a G protein-coupled receptor (GPCR), we find that neuronal G protein Gq (Gq), but not Go, may function downstream of Fmi to negatively regulate dendrite growth. Taken together, our results reveal a novel function of miR-9a in dendrite morphogenesis. Moreover, we suggest that Gq might mediate the intercellular signal of Fmi in neurons to suppress dendrite growth. Our findings provide novel insights into the complex regulatory mechanisms of microRNAs in dendrite development, and further reveal the interplay between the different components of Fmi, functioning in cadherin adhesion and GPCR signalling. (c) 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 225-237, 2016

submitted time 2016-05-05 Hits2698Downloads1617 Comment 0

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