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Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent

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National Science Review 2018年第5期5卷 728-739页

作者： Di Tian Zhengbing Yan Karl J.Niklas Wenxuan Han Jens Kattge Peter B.Reich Yongkai Luo Yahan Chen Zhiyao Tang Huifeng Hu ian J.wright Bernhard Schmid Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Max-Planck-Institute for Biogeochemistry State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Life Sciences Capital Normal University Department of Plant Biology Cornell University Department of Forest Resources University of Minnesota Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia10 Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Hawkesbury Institute for the Environment Western Sydney University Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural University

Leaf nitrogen(N) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf N and P stoichiometric relationships and shown that leaf N scales roughly as two-thirds the power of P. However, determining whether and how leaf N and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf N and P concentrations and the N:P ratios by functional group, climate zone and continent. The global overall mean leaf N and P concentrations were 18.9 mg gand 1.2 mg g, respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg gvs. 18.22 mg gfor N; and 1.64 mg gvs. 1.10 mg gfor P). Both leaf N and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest N and P concentrations(20.79 and 1.54 mg g) and Oceania had the smallest values(10.01 and 0.46 mg g). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of *** factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availa

关键词： leaf nitrogen phosphorus stoichiometry scaling exponent functional group biogeography

Lipocoacervate,a tunable vesicle for protein delivery

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Nano Research 2024年第10期17卷 9135-9140页

作者： Chia-Wei Yeh Nathaniel wright Chelsea Loh Nabeen Chu Yadong Wang Nancy E.and Peter C.Meinig School of Biomedical Engineering Cornell UniversityKimball Hall 290Ithaca 14853USA Human Biology Healthand Society.College of Human EcologyCornell UniversityIthaca 14853USA

Controlled delivery of proteins and other biologics is a growing medium of therapy for diseases previously *** we report a self-assembling,tunable vesicle for the controlled delivery of growth factors and *** made of heparin and a biocompatible polycation,PEAD,forms the core of the vesicle;lipids form the membrane of the *** call this vesicle lipocoacervate(LipCo),which has a high affinity for growth factors and cytokines due to *** is a tunable protein delivery *** vesicle size is controlled through polymer and salt *** functionalization enables potential for targeting capabilities with long-term storage through ***,the controlled delivery of therapeutics also avoids high toxicity to treated cells in *** we report on these key principles of LipCo assembly and design.

关键词： complex coacervate drug delivery protein delivery heparin lipid particle

A REDUCED ORDER SCHWARZ METHOD FOR NONLINEAR MULTISCALE ELLIPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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Journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin Li Stephen J.wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

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电与光:交换技术的阴阳面

通讯世界 2001年第11期7卷 20-22页

作者： ian wright Marc Schwager Rob Newman 赵锋

最近,业界对于纯光交换和电交换的讨论相当多.当对于光传输的需求迅猛增长时,人们不禁要问:究竟哪一种技术更适合于扩展并支持迅速发展的需求?随着新技术的不断涌现,很多人预言纯光交换将会很快取代电交换在核心电信网络中的地位.但是... 详细信息

最近,业界对于纯光交换和电交换的讨论相当多.当对于光传输的需求迅猛增长时,人们不禁要问:究竟哪一种技术更适合于扩展并支持迅速发展的需求?随着新技术的不断涌现,很多人预言纯光交换将会很快取代电交换在核心电信网络中的地位.但是仔细地研究电交换和纯光交换技术就会发现它们有着非常不同的特征,因此,不存在后者完全取代前者的可能性.这两种技术将很可能共存于电信网络中.

关键词：光交换机转发器 OC 电交换中继器电子设备光交换结构传输速率信号速率

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Disaster Awareness and Preparedness Among Older Adults in Canada Regarding Floods, Wildfires, and Earthquakes

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International Journal of Disaster Risk Science 2024年第2期15卷 198-212页

作者： Evalyna Bogdan Rachel Krueger Julie wright Kyle Woods Shaieree Cottar School of Administrative Studies Disaster and Emergency Management ProgramYork UniversityTorontoOntario M3J 1P3Canada Department of Geography and Environmental Management University of WaterlooWaterlooOntario N2L 3G1Canada Partners for Action Faculty of EnvironmentUniversity of WaterlooWaterlooOntario N2L 3G1Canada

Older adults are significantly impacted by natural hazards and disasters that are exacerbated by climate change. Understanding their awareness and preparedness is essential for enhancing disaster resilience. This study investigated the attitudes, actions, and recommendations of older adults regarding natural hazards that pose risks in their geographic area—specifically floods, wildfires, and/or earthquakes in Canada. Methods for this study included survey and focus groups with older adults(n = 161 and n = 10, respectively) and other high-risk groups from across Canada, that are vulnerable to these natural hazards. The main findings from this study are that current awareness and preparedness among older adults is low, though stronger perceptions of risks are associated with risks specific to geographic locations where respondents live. Several barriers, such as hazard vulnerability misperceptions, cost-related reasons, and lack of hazard awareness have resulted in low awareness and preparedness among these populations. The two main recommendations arising from this research are:(1) improve awareness and preparedness with tailor-made emergency preparedness materials for older adults;and(2) adopt community-based approaches to disaster preparedness through existing community groups to strengthen social connections with a focus on locally specific hazards. The findings from this research can be applied to other hazards, including heatwaves and pandemics.

关键词： Canada Community-based disaster risk management Disaster awareness and preparedness Disaster resilience Natural hazards Older adults

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The Meat of the Matter: Plant-Based Meat Analogue versus Traditional Meat Product Nutritional Quality

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Food Science and Human Wellness 2024年

作者： Arshia Shireen Amanda J wright Department of Human Health and Nutritional Sciences， University of Guelph Guelph， Ontario， Canada bDepartment of Human Health and Nutritional Sciences， University of Guelph Guelph， Ontario， Canada

Plant-based meat analogues (PBMA) are formulated to mimic the sensory characteristics of traditional meat products (TMP) using vegetarian ingredients and are increasingly popular with the trend towards plant-based diets， even among meat-eating consumers. This narrative review compared the nutritional quality of PBMA and TMP to broaden the discussion on the suitability of simulated meat products to substitute TMP， while exploring other attributes for their comparison. The complexity of PBMA and TMP means they are not entirely interchangeable. Importantly， PBMA health effects extend beyond their basic nutrient content and quality. Postprandial metabolism and satiety， for example， can be affected by product formulation， ingredient interactions， and thermomechanical processing involved in producing organoleptically acceptable PBMA. There are specific opportunities for low-sodium PBMA products to contribute to a healthy shift toward plant-based diets. In conclusion， PBMA cannot be assumed to be healthier than TMP. They should be designed with comprehensive consideration of composition and processing to ensure they support consumers who are adopting plant-based diets in realizing the theoretical health benefits.

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Outcomes of endoscopic submucosal dissection in cirrhotic patients: First American cohort

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World Journal of Hepatology 2024年第5期16卷 784-790页

作者： Robert Luke Pecha Fares Ayoub Ankur Patel Abdullah Muftah Michael W wright Mai A Khalaf Mohamed O Othman Department of Gastroenterology and Hepatology UC DavisSacramentoCA 95817United States Department of Gastroenterology and Hepatology Baylor College of MedicineHoustonTX 77030United States Internal Medicine Baylor College of MedicineHoustonTX 77030United States Department of Gastroenterology and Hepatology University of Texas Medical Branch at GalvestonGalvestonTX 77550United States Medical School Baylor College of MedicineHoustonTX 77030United States Department of Tropical Medicine Tanta UniversityTanta 31527Egypt

BACKGROUND Among patients with cirrhosis and pre-malignant or early malignant mucosal lesions,surgical intervention carries a much higher bleeding *** such lesions are discovered,endoscopic submucosal dissection(ESD)may offer curative therapy with lower risks than surgery and improved outcomes compared to traditional endoscopic *** To evaluate the outcomes of ESD in patients with *** Patients with cirrhosis undergoing ESD between July 2015 and August 2022 were retrospectively matched in 1:2 fashion to controls based on lesion location,size,and anticoagulation *** outcomes were compared between *** A total of 64 Lesions from 59 patients were included(16 cirrhosis,43 control).There were no differences in patient or lesion characteristics between *** bloc and curative resection was achieved in 84.21%,78.94%of the cirrhosis group and 88.89%,68.89%of controls,respectively,with no significant *** patients had significantly higher rates of intra-procedural coagulation grasper use for control of bleeding(47.37%vs 20%;P=0.02).There were otherwise no significant differences in adverse event *** the 29 patients with follow up,we found higher rates of recurrence in the cirrhosis group compared to controls(40%vs 5.26%;P=0.019),however this effect did not persist on multivariable analysis controlling for known *** ESD may be safe and effective in patients with *** procedure related outcomes were not significantly different between ***-procedural bleeding requiring use of the coagulation grasper use was expectedly higher in the cirrhosis group given the known effects of liver disease on hemostasis.

关键词： Endoscopic aubmucosal dissection Cirrhosis Advanced polypectomy Intraprocedural bleeding Colon cancer

Temporal trends and practice variation of paediatric diagnostic tests in primary care:retrospective analysis of 14 million tests

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Family Medicine and Community Health 2024年第4期12卷 1-8页

作者： Elizabeth T Thomas Diana R Withrow Cynthia wright Drakesmith Peter J Gill Rafael Perera-Salazar Carl Heneghan Centre for Evidence-Based Medicine Nuffield Department of Primary Care Health SciencesUniversity of OxfordOxfordUK Nuffield Department of Primary Care Health Sciences University of OxfordOxfordUK Department of Pediatrics University of TorontoTorontoOntarioCanada Hospital for Sick Children TorontoOntarioCanada

Objective The primary objective was to investigate temporal trends and between-practice variability of paediatric test use in primary *** and analysis This was a descriptive study of population-based data from Clinical Practice Research Datalink Aurum primary care consultation records from 1 January 2007 to 31 December *** aged 0–15 who were registered to one of the eligible 1464 general practices and had a diagnostic test code in their clinical record were *** primary outcome measures were(1)temporal changes in test rates measured by the average annual percent change,stratified by test type,gender,age group and deprivation level and(2)practice variability in test use,measured by the coefficient of *** 14299598 diagnostic tests were requested over 27.8 million child-years of observation for 2542101 *** test use increased by 3.6%/year(95%CI 3.4 to 3.8%)from 399/1000 child-years to 608/1000 child-years,driven by increases in blood tests(8.0%/year,95%CI 7.7 to 8.4),females aged 11–15(4.0%/year,95%CI 3.7 to 4.3),and children from the most socioeconomically deprived group(4.4%/year,95%CI 4.1 to 4.8).Tests subject to the greatest temporal increases were faecal calprotectin,fractional exhaled nitric oxide and vitamin *** classified as high-use and high-practice variability were iron studies,coeliac testing,vitamin B12,folate,and vitamin *** In this first nationwide study of paediatric test use in primary care,we observed significant temporal increases and practice variability in *** reflects inconsistency in practice and diagnosis rates and a scarcity of evidence-based *** test use generates more clinical activity with significant resource implications but conversely may improve clinical *** research should evaluate whether increased test use and variability are warranted by exploring test indications and test results and directly examine how increased test use impacts

关键词： vitamin nationwide stratified

CYP3A5 unexpectedly regulates glucose metabolism through the AKT-TXNIP-GLUT1 axis in pancreatic cancer

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Genes & Diseases 2024年第4期11卷 381-399页

作者： Ming Shao Qingfei Pan Haiyan Tan Jing Wu Ha Won Lee Andrew D.Huber William C.wright Ji-Hoon Cho Jiyang Yu Junmin Peng Taosheng Chen Department of Chemical Biology and Therapeutics St.Jude Children's Research HospitalMemphisTN 38105USA Department of Computational Biology St.Jude Children's Research HospitalMemphisTN 38105USA Center for Proteomics and Metabolomics St.Jude Children's Research HospitalMemphisTN 38105USA Department of Structural Biology St.Jude Children's Research HospitalMemphisTN 38105USA Department of Developmental Neurobiology St.Jude Children's Research HospitalMemphisTN 38105USA

CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in ***,it remains unclear whether CYP3A5 directly influences cancer *** this report,we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal ***-omics analysis showed that CYP3A5 knockdown re-sults in a decrease in various glucose-related metabolites through its effect on glucose trans-port.A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP,a negative regulator of ***,CYP3A5-generated reactive oxygen species were proved to be responsible for atten-uating the AKT-4EBP1-TXNIP signaling ***3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic *** together,our results,for the first time,reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.

关键词： Cell migration CYP3A5 Glucose metabolism GLUT1 Pancreatic cancer TXNIP