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Welfare and Market Impacts of Food Safety Measures in China: Results from Urban Consumers' Valuation of Product Attributes

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Journal of Integrative Agriculture 2014年第6期13卷 1404-1411页

作者： david l. Ortega H. Holly Wang Nicole J. Olynk Widmar Department of Agricultural Foodand Resource EconomicsMichigan State University Department of Agricultural Economics Purdue University

This study provides an economics assessment of various food safety measures in China. A choice experiment approach is used to elicit Chinese consumer preferences for various food safety attributes using data from a 2008 urban consumer survey. An alternative welfare calculation is used to model aggregate market impacts of select food safety measures. Our results show that the largest welfare gains are found in the current government-run certiifcation program. The implementation of a third-party certiifcation system, a traceability network and a product label would generate signiifcant value and would help reduce current system inefifciencies in China. This study builds on previous research and provides an alternative approach for calculating consumer valuation of safety and quality attributes that can be used to estimate aggregate economic and welfare impacts.

关键词： food safety consumer welfare food policy China

Profile of retinal diseases in adult patients attending two major eye clinics in Kinshasa,the Democratic Republic of Congo

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International Journal of Ophthalmology(English edition) 2020年第10期13卷 1652-1659页

作者： Nelly N.Kabedi david l.Kayembe Jean-Claude Mwanza Departmemt of Ophthalmology School of MedicineUniversity of KinshasaKinshasa XIDemocratic Republic of Congo Department of Ophthalmology School of MedicineUniversity of North Carolina at Chapel HillNC 27599USA

AIM:To determine the frequency and types of retinal diseases and the extend of the related visual loss in adult patients attending two public eye clinics of Kinshasa,Democratic Republic of ***:Review of medical records of patients with retinal diseases seen in the major eye clinics in Kinshasa,the University Hospital of Kinshasa(UHK)and Saint Joseph Hospital(SJH),from January 2012 to December *** and diagnoses were retrieved and *** measures were frequency and prevalence of retinal diseases,blindness and low ***:A total of 40965 patients aged 40 y or older were examined during this period in both *** these,1208 had retinal disease,giving a 3-year and an annual prevalence of 3%and 1%,*** age was 61.7±10.7 y,and 55.8%of the patients were *** hypertension(68.1%)and diabetes(43.3%)were the most common systemic *** retinopathy(41.8%),diabetic retinopathy(37.9%),age-related macular degeneration(AMD;14.6%),and chorioretinitis and retinal vein occlusion(7.3%each)were the most common retinal diseases,with 3-year prevalence rates of 1.3%,1.0%,0.43%,and 0.21%*** low vision and blindness were present in 26.8%and 8.4%of the patients at *** causes of low vision and blindness were diabetic retinopathy(14.8%),AMD(4.9%),retinal detachment(2.8%),and retinal vein occlusion(2.5%).The prevalence was significantly higher among males than females,and at the UHK than ***:Retinal diseases are common among Congolese adult patients attending eye clinics in *** cause a significant proportion of low vision and blindness.

关键词： retinal disorders Kinshasa,Democratic Republic of Congo sub-Saharan Africa pattern

Immunopathology of inflammatory bowel disease

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World Journal of Gastroenterology 2014年第1期20卷 6-21页

作者： Kori l Wallace li-Bo Zheng Yoshitake Kanazawa david Q Shih F Widjaja Foundation Inflammatory Bowel and Immunobiology Research InstituteCedars-Sinai Medical CenterLos Angeles CA 90048United States Department of Gastroenterology The Second Hospital of Hebei Medical University

Inflammatory bowel disease(IBD)results from a complex series of interactions between susceptibility genes,the environment,and the immune *** host microbiome,as well as viruses and fungi,play important roles in the development of IBD either by causing inflammation directly or indirectly through an altered immune *** technologies have allowed researchers to be able to quantify the various components of the microbiome,which will allow for future developments in the etiology of *** components of the mucosal immune system are implicated in the pathogenesis of IBD and include intestinal epithelial cells,innate lymphoid cells,cells of the innate(macrophages/monocytes,neutrophils,and dendritic cells)and adaptive(T-cells and B-cells)immune system,and their secreted mediators(cytokines and chemokines).Either a mucosal susceptibility or defect in sampling of gut luminal antigen,possibly through the process of autophagy,leads to activation of innate immune response that may be mediated by enhanced toll-like receptor *** antigen presenting cells then mediate the differentiation of na?ve T-cells into effector T helper(Th)cells,including Th1,Th2,and Th17,which alter gut homeostasis and lead to *** this review,the effects of these components in the immunopathogenesis of IBD will be discussed.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerat

A facile and sensitive method of quantifying glutaminase binding to its ninhibitor CB-839 in tissues

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Journal of Genetics and Genomics 2020年第7期47卷 389-395页

作者： Yicheng Chen Yiqing Zhao david l.Bajor Zhenghe Wang J.Eva Selfridge Department of Genetics and Genome Sciences Case Western Reserve University10900 Euclid AvenueClevelandOH44106USA Department of Medicine Case Western Reserve University10900 Euclid AvenueClevelandOH.44106USA Case Comprehensive Cancer Center Case Western Reserve University10900 Euclid AvenueClevelandOH44106USA Seidman Cancer Center University Hospitals Cleveland Medical CenterWOO Euclid AvenueClevelandOH44106USA

Many cancer types reprogram their metabolism to become addicted to *** of the critical enzymes in the utilization of glutamine in these cells is ***-839(telaglenastat)is a drug that targets glutaminase that is currently being evaluated in many clinical trials for efficacy in various cancer types that are known to be driven by glutamine *** its use,there are limited assays available for testing the pharmacodynamic on-target effects of CB-839 on the limited,small-volume patient samples that are obtained in early-phase clinical ***,we developed an assay based on the cellular thermal shift assay technique using AlphalllSA technology to show that CB-839 specifically engages glutaminase in colon cancer cell lines in vitro and in minute quantities of mouse xenograft ***,we show that this assay detects CB-839 binding to glutaminase in platelets of patients collected while receiving CB-839 on a clinical *** assay may be used to study the pharmacodynamic profile of CB-839 in very small tissue samples obtained from patients on a clinical trial and may be useful infuture studies designed to screen other in hibitors of glutaminase.

关键词： Glutaminase Method Cancer

Serum Vitamin D levels of Children with Vernal Keratoconjunctivitis and Normal in Kinshasa

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Open Journal of Pediatrics 2022年第2期12卷 297-308页

作者： léon Muamba Nkashama david Kayembe lubeji Mireille Solange Nganga Dieu Donné Nyembue Tshipukane Department of Ophthalmology University Hospital of Kinshasa Kinshasa Democratic Republic of the Congo Clinical Biology Department University Hospital of Kinshasa Kinshasa Democratic Republic of the Congo Ear Nose and Throat Department University Hospital of Kinshasa Kinshasa Democratic Republic of the Congo

Background: Data on the serum vitamin D3 levels of vernal keratoconjunctivitis (VKC) children are not known well in Central Africa. Children with vernal keratoconjunctivitis are less exposed to sunlight. There is no study that shows the breadth of the serum vitamin D3 levels of vernal keratoconjunctivitis children and normal in our setting. Purpose: This study aimed to compare the serum 25-hydroxy vitamin D [25(OH)D3] levels of children with and without VKC. Methods: An observational, case-control study was performed from September 2019 to February 2020 in the Ophthalmology Department and the Clinical Biology Department of the University Hospital of Kinshasa. The case group was recruited consecutively in the consultation while the control group was enrolled in the nearest Rehoboth school complex using a systematic sample method (k = 4) on the presence register. Both cases and controls underwent the routine ophthalmological examination of the anterior segment and serum vitamin D3 levels were measured in both cases and controls using Mindray Chimic-luminescence (Cl)-1200i. Data were entered in Microsoft Sheets and analyzed using SPSS version 20.0. The Mann-Whitney-U test (M-U), and the t-Student test were used respectively to compare the mean serum vitamin D3 levels in both cases and controls. The correlation of Spearman (rho) was used to determine the association between Body Mass Index and serum vitamin D3 levels in the case group. Results: A total of 75 children with VKC (mean age 7.8 ± 4.4 years) and 75 children without VKC non-atopic control group (mean age 7.9 ± 4.3 years) were enrolled in this study. The vitamin D3 deficiency was more frequent among the case group than in the control group (40% vs 8%, p = 0.0001). Vitamin D3 insufficiency was more frequent in the case group than in the control group (33.3% vs 18.6%, p = 0.04). The mean serum vitamin 25(OH)D3 levels were statistically lower in children with VKC compared to those without (25.5 ± 8.7 ng/ml and 44.

关键词： Serum 25(OH)D3 Time Spent Outdoors Vernal Keratoconjunctivitis Body Mass Index

Rationally designed synthesis of bright AgInS2/ZnS quantum dots with emission control

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Nano Research 2020年第9期13卷 2438-2450页

作者： Jose X.Soares K.david Wegner david S.M.Ribeiro Armindo Melo Ines Hausler Joao l.M.Santos Ute Resch-Genger lAQV-REQUIMTE Department of Chemical SciencesLaboratory of Applied ChemistryFaculty of PharmacyUniversity of PortoRua de Jorge Viterboferreira228Porto4050-313Portugal Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard-Willstaetter-Strasse 1112489 BerlinGermany lAQV-REQUIMTE Laboratorio de Bromatologia e HidrologiaDepartamento de Ciencias QutmicasFaculdade de Farmacia da Universidade do PortoRua de Jorge Viterboferreira228Porto4050-313Portugal Technische Universitat Berlin Institutfiir Optik und Atomare PhysikStrafie des 17.Juni 13510623 BerlinGermany

In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,their high photoluminescence(Pl)quantum yields(QYs)in the red and near infrared(NIR)region,and their inherently low ***,their oxygen-insensitive long Pl lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter Pl *** overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their Pl properties,we assessed and modelled the synthesis of high-quality MPA-capped AglnS2/ZnS(AlS/ZnS)*** refined parameters included reaction time,temperature,Ag:In ratio,S:In ratio,Zn:In ratio,MPA:ln ratio,and pH using a design-of-experiment *** for the optimization was provided by mathematical models developed for the application-relevant Pl parameters,maximum Pl wavelength,QY,and Pl lifetime as well as the elemental composition in terms of Ag:ln:Zn *** these experimental data-based models,MPA:ln and Ag:ln ratios and pH values were identified as the most important synthesis parameters for Pl control and an insight into the connection of these parameters could be ***,the experimental conditions to synthetize QDs with tunable emission and high QY were *** excellent agreement between the predicted and experimentally found Pl features confirmed the reliability of our methodology for the rational design of high quality AlS/ZnS QDs with defined Pl *** approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs.

关键词： quantum dot core/shell nanoparticle silver indium sulfide microw ave-assisted synthesis design of experim ent photoluminescence

(EDTA)^(4-) supplements as superior modifier of the in-vitro-degradation properties of the magnesium alloy coated through discharge-assisted process

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Journal of Magnesium and Alloys 2023年第3期11卷 945-957页

作者： Zeeshan Ur Rahman Maqsood Ali Ye-Tang Pan david G.Churchill Bon Heun Koo College of Mechatronic Engineering Changwon National UniversityChangwonGyeongsangnam-doRepublic of Korea Department of Regenerative Medicines College of MedicinesSoonChunhyang UniversityCheonanRepublic of Korea National Engineering Technology Research Center of Flame Retardant Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijingPR China Department of Chemistry Molecular Logic Gate LaboratoryKorea Advanced Institute of Science and Technology(KAIST)Republic of Korea

The(EDTA)^(4-)organic substituents were supplemented with alkaline silicates electrolyte,however in varying concentration to explore the microstructure,chemical composition and subsequent effects on the biodegradation of the PEO coated Mg AZ91 *** surface analysis-,carried out through SEM,samples with zero-(EDTA)^(4-)were found-,lacking pancake structural features;however,supplementing electrolyte with(EDTA)^(4-),bulky and layered pancakes were obtained with minimum cracks and minimum porosity for *** the phase and inner layer analysis,it was found that EDTA can significantly alter the surface layers composition and could act as a passivation agent-;however,individual polycrystalline phases were not found to *** hardness value obtained for EDT-1 was~909.69 HV,the highest value found here which occurs with the shallowest indents found in this ***-vitro degradation analysis was carried out using potentiodynamic polarization at room temperature,cyclic polarization at RT and high fever conditions(HFT~40°C).The corrosion potential for coated AZ91 was obtained as a positive value of~0.1 V,for the first time in the PEO research;however,the results were not supported by the cyclic polarization tests at room temperature and at *** post corrosion microstructural analysis confirmed the effective role of EDTA up to 1.0 g·l^(-1)and revealed the formation of thin films during the forward polarization at HFT.

关键词： EDTA Soft plasma Magnesium Biodegradation Corrosion SBF

陆生蜗牛壳体高分辨率的稳定氧同位素记录与季节的干湿变化

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第四纪研究 2022年第4期42卷 1159-1167页

作者：王蜜 david l DETTMAN 倪观忠胡涵余子莹陈京平丁璇王鑫兰州大学资源环境学院甘肃兰州730000 Department of Geosciences University of ArizonaTucsonAZ85721

季节变化是气候系统的基本特征,然而受研究材料和方法所限,陆相沉积序列中难以获得古气候的季节变化信息。文章选择兰州地区,在旱季和雨季分别采集两个现生条华蜗牛(Cathaica fasciola),通过沿壳体生长轴高分辨率取样分析,发现兰州地区... 详细信息

季节变化是气候系统的基本特征,然而受研究材料和方法所限,陆相沉积序列中难以获得古气候的季节变化信息。文章选择兰州地区,在旱季和雨季分别采集两个现生条华蜗牛(Cathaica fasciola),通过沿壳体生长轴高分辨率取样分析,发现兰州地区旱季生长的蜗牛壳体稳定氧同位素组成(δ^(18)O)整体偏正、雨季生长的壳体显著偏负,单个壳体内部δ^(18)O的波动幅度捕获了季节干湿变化信号。综合现代观测、黄土高原其他地区记录、通量平衡模式等证据,提出蜗牛壳体δ^(18)O旱季偏正,主要受蒸发效应和温度影响,蒸发效应可能更为重要;蜗牛壳体δ^(18)O雨季偏负,主要受降水氧同位素组成和温度影响。蜗牛壳体高分辨率的稳定氧同位素研究在揭示亚洲古季风季节干湿变化方面有巨大应用潜力,系统的现代过程研究是推动该方法进一步发展的关键所在。

关键词：蜗牛壳体稳定氧同位素季节性干湿变化

Chemically derived graphene quantum dots for high-strain sensing

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Journal of Materials Science & Technology 2023年第10期141卷 110-115页

作者： Shujun Wang Francesco lenzini Dechao Chen Philip Tanner Jisheng Han david Thiel Mirko lobino Qin li Queensland Miro-and Nanotechnology Centre Griffith UniversityNathan CampusBrisbane QLD 4111Australia School of Engineering and Built Environment Griffith UniversityNathan CampusBrisbane QLD 4111Australia Centre for Quantum Dynamics Griffith UniversityNathan CampusBrisbane QLD 4111Australia Department of Industrial Engineering University of Trento38122Italy

Graphene quantum dots(GQDs)refer to graphene fragments with a lateral dimension typically less than 100 nm,which possess unique electrical and optical properties due to the quantum confinement *** this study,we demonstrate that chemically derived graphene quantum dots show great potential for making highly stretchable and cost-effective strain sensors via an electron tunneling ***-able strain sensors are critical devices for the field of flexible or wearable electronics which are expected to maintain function up to high strain values(>30%).However,strain sensors based on conventional materials(*** or semiconductors)or metal nanoparticles(*** or silver nanoparticles)only work within a small range of strain(*** former have a working rangelatterly dropcasting solution-processed GQDs between the interdigitated electrodes on polydimethylsiloxane,we obtained devices that can function in the range from 0.06%to over 50%ten-sile strain with both the sensitivity and working range conveniently adjustable by the concentration of GQDs *** study provides a new concept for practical applications of GQDs,revealing the poten-tial of this material for smart applications such as artificial skin,human-machine interfaces,and health monitoring.

关键词： Graphene quantum dots Graphene Strain Sensor Electron tunneling