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Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： Sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUMEU Beatriz GUZMAN Pablo VARGAS Jens M. OLESEN Anna TRAVESET Carlos VERA Edgar BENAVIDES Manuel NOGALES Institut Mediterrani d'Estudis Avanqats (CSIC-UIB) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain Department of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador Department of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assumed to be constrained by body size;only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (Microlophus spp.) were studied on the eleven largest Galapagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more importa nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. Most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germi nation inhibitors) might in crease the chances that at least some seeds find suitable recruitment conditi ons. We con eluded that lizards are importa nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： Microlophus oceanic islands plant-animal interactions seed disperser size seed dispersal effectiveness seedling emergence

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Seismic analysis of cantilever earth retaining walls embedded in dry sand by simplified approaches and finite element method

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岩土力学 2022年第6期43卷 1617-1634页

作者： FERRO edgar OSS Andrea SIMEONI Lucia Department of Civil Environmental and Mechanical Engineering University of TrentoTrentoItaly SWS Engineering S.p.A. TrentoItaly

In engineering practice simplified methods are essential to the seismic design of embedded earth retaining walls,as fullydynamic numerical analyses are costly,time-consuming and require specific expertise.Recently developed pseudostatic methods provide earth stresses and internal forces,even in those cases in which the strength of the soil surrounding the structure is not entirely mobilised.Semiempirical correlations or Newmark sliding block method provide an estimate of earthquake-induced permanent displacements.However,the use of these methods is hindered by uncertainties in the evaluation of a few input parameters,affecting the reliability of the methods.This study uses 1 D site response analyses and 2 D fully-dynamic finite element analyses to show that simplified methods can provide a reasonable estimate of the maximum bending moment and permanent displacements for stiff cantilever walls embedded in uniform sand,providing that a few input parameters are evaluated through semiempirical correlations and a simple 1 D site response analysis.

关键词： embedded retaining wall seismic design finite elements pseudostatic methods Newmark permanent displacement

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Is activation of GDNF/RET signaling the answer for successful treatment of Parkinson's disease?A discussion of data from the culture dish to the clinic

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Neural Regeneration Research 2022年第7期17卷 1462-1467页

作者： James A.Conway edgar R.Kramer Institute of Translational and Stratified Medicine Peninsula Medical SchoolFaculty of HealthUniversity of PlymouthDevonUK

The neurotrophic signaling of glial cell line-derived neurotrophic factor(GDNF)with its canonical receptor,the receptor tyrosine kinase RET,coupled together with the GDNF family receptor alpha 1 is important for dopaminergic neuron survival and physiology in cell culture experiments and animal models.This prompted the idea to try GDNF/RET signaling as a therapeutic approach to treat Parkinson’s disease with the hallmark of dopaminergic cell death in the substantia nigra of the midbrain.Despite several clinical trials with GDNF in Parkinson’s disease patients,which mainly focused on optimizing the GDNF delivery technique,benefits were only seen in a few patients.In general,the endpoints did not show significant improvements.This suggests that it will be helpful to learn more about the basic biology of this fascinating but complicated GDNF/RET signaling system in the dopaminergic midbrain and about recent developments in the field to facilitate its use in the clinic.Here we will refer to the latest publications and point out important open questions in the field.

关键词： α-synuclein clinical trials dopaminergic neurons glial cell line-derived neurotrophic factor GFRα1 gut-brain axis Nedd4 Parkin Parkinson’s disease RET

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Single-cell transcriptome profiling of human HSCs during development:new insights into HSC ontogeny

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Signal Transduction and Targeted Therapy 2023年第3期8卷 877-878页

作者： edgar Grinstein Csaba Mahotka Department of Hematology Oncology and Clinical ImmunologyMedical FacultyHeinrich Heine UniversityDüsseldorfGermany Institute of Pathology Medical FacultyHeinrich Heine UniversityDüsseldorfGermany

A study recently published in Nature reported a single-cell transcriptome map of human hematopoietic stem cells(HSCs)and a gene expression signature that distinguishes nascent HSCs from non-HSCs during prenatal development.1 This transcriptome map provides an important tool for further elucidation of human HSC ontogeny and could also serve as a guide for generation of transplantable HSCs ex vivo,1 to widen the therapeutic application of HSCs.

关键词： HSCs transcriptome hematopoietic

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ICU中心静脉相关血流感染五年的流行病学、危险因素和病原学演变

ICU中心静脉相关血流感染五年的流行病学、危险因素和病原学演变

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作者： Theresia edgar Lutufyo 山东大学

学位级别：硕士

研究目的:中心静脉导管(CVCs)作为治疗危重症患者的工具,在重症监护病房(ICU)中广泛应用。然而,CVC的应用与血流感染呈正相关。研究发现,近年来CVC相关血流感染(CLABSI)的发生率逐年增加,是ICU患者血流感染的主要原因之一。因此,我们强... 详细信息

研究目的:中心静脉导管(CVCs)作为治疗危重症患者的工具,在重症监护病房(ICU)中广泛应用。然而,CVC的应用与血流感染呈正相关。研究发现,近年来CVC相关血流感染(CLABSI)的发生率逐年增加,是ICU患者血流感染的主要原因之一。因此,我们强调研究CLABSI在ICU患者流行病学和危险因素中的重要性并且分析了 CLABSI在ICU人群中五年的发生率,致病病原体和危险因素。研究方法:对2016年1月至2020年12月期间在山东大学齐鲁医院ICU治疗的患者进行回顾性研究。纳入标准为患者年龄≥18岁,具有一根以上CVC,收集其外周血和中心静脉导管尖端的培养结果。排除在院外放置CVC的患者,以及无外周血或中心静脉导管尖端培养结果的患者,或主要终点数据缺失的患者。收集序贯器官衰竭评估(SOFA)评分、急性生理和慢性健康评估Ⅱ(APACHEII)评分、Charlson共病指数(CCI)评分、CVC置入时间和拔除时间等数据,使用Logistic回归等方法以分析CLABSI的病原学结果。结果:我们共收集了 1920例CVC,其中507例符合纳入标准。本研究中患者的平均年龄为60.31±16.64岁,其中355名(70%)男性。CVC置入部位中,颈内静脉CVC为101根,锁骨下静脉CVC为113根,股静脉部位CVC为293根。CVC放置的原因包括输注液体和血液制品201(39.6%)根、连续肾脏替代治疗(CRRT)216(42.6%)根、血流动力学监测53(10.5%)根、体外膜氧合治疗(ECM0)26(5.1%)根、肠外营养1(0.2%)、双分子血浆吸附系统(DPMAS)1(0.2%)根和血浆置换8(1.6%)根。在507根CVC中,发生CLABSI有52根,判定定植有70根。CLABSI病例在感染发生前CVC放置的平均持续时间为1.60±5.72天,定植CVC平均持续时间为1.88±6.04天。52例CLABSI由52种微生物引起。革兰阴性杆菌分别为多重耐多药肺炎克雷伯菌8(1.6%),鲍曼不动杆菌8(1.6%),耐碳青霉烯类耐药肠杆菌科2(0.4%),洋葱伯克霍尔德菌1(0.2%)。在革兰阳性菌中,分别为耐甲氧西林金黄色葡萄球菌11(2.2%),甲氧西林敏感金黄色葡萄球菌1(0.2%),条纹棒状杆菌1(0.2%),粪肠球菌4(0.8%)。在真菌中,仅发现白色念珠菌16(3.2%)。455份(89.7%)样本中未发现微生物生长。通过进行多因素Logistic回归分析,我们发现年龄(P值=0.004)、Charlson合并症指数(P值<0.001)和CVC放置持续时间(P值=0.001)与CLABSI风险升高有关。结论:我们的研究揭示了 5年期间ICU患者CLABSI的发生率平均为2.2‰,危险因素是高龄、基础病和留置时间大于8天,主要致病微生物主要为G-和白色念珠菌。

关键词：重症监护中心静脉导管血流感染流行病学危险因素病原体

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Controllable multi-domain semantic artwork synthesis

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Computational Visual Media 2024年第2期10卷 355-373页

作者： Yuantian Huang Satoshi Iizuka edgar Simo-Serra Kazuhiro Fukui Department of Computer Science University of TsukubaTsukuba 305-8577Japan Department of Computer Science and Engineering Waseda UniversityTokyo 169-8050Japan

We present a novel framework for the multidomain synthesis of artworks from semantic layouts.One of the main limitations of this challenging task is the lack of publicly available segmentation datasets for art synthesis.To address this problem,we propose a dataset called ArtSem that contains 40,000 images of artwork from four different domains,with their corresponding semantic label maps.We first extracted semantic maps from landscape photography and used a conditional generative adversarial network(GAN)-based approach for generating high-quality artwork from semantic maps without requiring paired training data.Furthermore,we propose an artwork-synthesis model using domain-dependent variational encoders for high-quality multi-domain synthesis.Subsequently,the model was improved and complemented with a simple but effective normalization method based on jointly normalizing semantics and style,which we call spatially style-adaptive normalization(SSTAN).Compared to the previous methods,which only take semantic layout as the input,our model jointly learns style and semantic information representation,improving the generation quality of artistic images.These results indicate that our model learned to separate the domains in the latent space.Thus,we can perform fine-grained control of the synthesized artwork by identifying hyperplanes that separate the different domains.Moreover,by combining the proposed dataset and approach,we generated user-controllable artworks of higher quality than that of existing approaches,as corroborated by quantitative metrics and a user study.

关键词： semantic artwork synthesis generative adversarial network(GAN) datasets non-photorealistic rendering

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The reversed intra- and extracellular pH in tumors as a unified strategy to chemotherapeutic delivery using targeted nanocarriers

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Acta Pharmaceutica Sinica B 2021年第8期11卷 2243-2264页

作者： edgar Pérez-Herrero Alberto Fernández-Medarde Departamento de Ingeniería Química y Tecnología Farmacéutica Universidad de La LagunaLa Laguna 38206TenerifeSpain Instituto Universitario de Bio-Orgánica Antonio González Universidad de La LagunaLa Laguna 38206TenerifeSpain Instituto Universitario de Tecnologías Biomédicas Universidad de La LagunaLa Laguna 38200TenerifeSpain Instituto de Biología Molecular y Celular Del Cáncer Centro de Investigación Del Cáncer(USAL-CSIC)Salamanca 37007Spain

Solid tumors are complex entities,comprising a wide variety of malignancies with very different molecular alterations.Despite this,they share a set of characteristics known as"hallmarks of cancer"that can be used as common therapeutic targets.Thus,every tumor needs to change its metabolism in order to obtain the energy levels required for its high proliferative rates,and these adaptations lead to alterations in extra-and intracellular pH.These changes in p H are common to all solid tumors,and can be used either as therapeutic targets,blocking the cell proton transporters and reversing the pH changes,or as means to specifically deliver anticancer drugs.In this review we will describe how proton transport inhibitors in association with nanocarriers have been designed to block the pH changes that are needed for cancer cells to survive after their metabolic adaptations.We will also describe studies aiming to decrease intracellular pH in cancer using nanoparticles as molecular cages for protons which will be released upon UV or IR light exposure.Finally,we will comment on several studies that have used the extracellular pH in cancer for an enhanced cell internalization and tumor penetration of nanocarriers and a controlled drug delivery,describing how nanocarriers are being used to increase drug stability and specificity.

关键词： pH-Gradient inversion Metabolism of glucose Proton transport inhibitors Proton-caged carriers Chemotherapy Targeted drug delivery pH-Sensitive nanocarriers Warburg effect Cancer

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企业社交媒体使用对乌干达银行业绩效的影响

企业社交媒体使用对乌干达银行业绩效的影响

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作者： ABAHO edgar 浙江工商大学

学位级别：硕士

The purpose of this study was to establish value of Enterprise Social Media（ESM）usage on the employee performance in the banking industry in Uganda and to clarify the impact of enterprise social media usage on employee performance in the banking industry in Uganda.Data was collected from 240 respondents using a structured questionnaire which was administered to the respondents through an online link（http://***/x/Ctw XDGw Q）.The questionnaire was with a five-point Likert scale containing questions concerning self-presenting,information sharing and entertainment.The evidence from the study shows that social media plays a very significant role in employee performance in the banking sector in Uganda.Therefore,the study concludes that more efforts are needed to push ESM through providing more easy and convenient mobile applications that are easily understood by all clients and employees of different origin.

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种植森林在乌干达中部经济发展和社会福利中的作用

种植森林在乌干达中部经济发展和社会福利中的作用

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作者： Tumwine edgar 北京林业大学

学位级别：硕士

人工林建设是推动乌干达经济活动的增长引擎,也是促进家庭收入的积极手段。但是,森林覆盖率的下降使这个国家的林业发展陷入迟滞。因此,本研究的目标分析了人工林在乌干达经济发展和社会福利中的作用,这些家庭集中在乌干达中部地区,作... 详细信息

人工林建设是推动乌干达经济活动的增长引擎,也是促进家庭收入的积极手段。但是,森林覆盖率的下降使这个国家的林业发展陷入迟滞。因此,本研究的目标分析了人工林在乌干达经济发展和社会福利中的作用,这些家庭集中在乌干达中部地区,作为天然森林的替代品。因此,本研究分析了以乌干达中部地区家庭为中心以人工林替代天然林对乌干达经济发展和社会福利中的影响。本研究收集的主要数据来源于在乌干达中部不同地区进行的家庭访谈,包括Mityana、Mubende和Mpigi等地区,共有250户家庭。其余数据来源于乌干达主要的统计部门:乌干达统计局（UBOS）、水与环境部（MWE）、国家森林管理局（NFA）和国家环境管理局（NEMA）。研究还将采用不同的数据分析机制,对研究结果进行分析和进一步解释,收集数据,并开发计量经济学模型。Excel和STATA版本13用于分析描述性统计方法和回归分析中的数据,提取了突出的结果,有助于解释人工林、家庭和不同变量之间的关系。根据人工林对经济发展和社会福利的作用分析得出的结果发现:木材产品、林地面积、非木材产品、人均收入和农业产出对家庭收入有着显著的积极影响,因此人工林的发展对乌干达和乌干达中部的经济发展和社会福利有着积极的贡献,特别值得注意的是,森林砍伐率的增加也会对家庭收入产生严重的负面影响。研究分析发现,由于人口、移居和城市化进程的加快,这些因素会通过人造林对经济发展产生负面作用的影响,从而对家庭收入产生显著的负面影响。同时,由于自然森林覆盖率正在以惊人的速度下降,因此需要增加人工林的开发。最后,研究探讨了人工林在经济发展及社会福利方面所扮演的角色,分析了人工林在弥补天然林对经济社会发展的差距上所起到的影响。最后,它认为,人工林在改善家庭福利和收入方面起着至关重要的作用,因此,整个区域根据调查结果建议鼓励植树,因为它仍然小规模地进行。

关键词：植树造林社会福利家庭收入

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钙钛矿型催化剂的设计合成与环己烷部分氧化性能研究

钙钛矿型催化剂的设计合成与环己烷部分氧化性能研究

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作者： edgar Muhumuza 中国石油大学(华东)

学位级别：硕士

环己烷选择性氧化是工业上最常用的制造环己醇和环己酮(统称为KA油)的过程,而KA油通常被用作生产尼龙6和尼龙6,6的中间体。目前工业过程中,多采用钴或锰基盐作为均相催化剂。但均相催化过程主要存在以下问题:为了抑制过量副产物的形成,... 详细信息

环己烷选择性氧化是工业上最常用的制造环己醇和环己酮(统称为KA油)的过程,而KA油通常被用作生产尼龙6和尼龙6,6的中间体。目前工业过程中,多采用钴或锰基盐作为均相催化剂。但均相催化过程主要存在以下问题:为了抑制过量副产物的形成,环己烷的转化率控制在非常低的水平,主要产物的选择性差;需要循环大量未反应的环己烷,操作成本高以及均相催化剂对环境造成污染等。因此,实现高的环己烷转化率以及高的KA油选择性仍然面临着巨大的挑战。不可否认,近年来负载型贵金属纳米催化剂在环己烷部分氧化反应中表现出很高的活性和选择性。然而,其较高的成本和快速失活问题限制了其工业应用。钙钛矿材料由于其特殊的理化性质,如优良的氧化还原和氧迁性能,已成为低温氧化反应中的新型催化材料,引起了广泛的关注。本论文通过改进的柠檬酸法合成了一系列的过渡金属钙钛矿La BO(B=Mn,Fe,Co,Ni)材料并用于环己烷部分氧化过程。研究表明,煅烧温度,络合剂的类型及络合剂与金属离子的比例是影响催化剂结构的主要原因。钴基钙钛矿(LaCoO)在环己烷部分氧化反应过程中表现出优异的活性和选择性。在150 C反应1小时后,环己烷的转化率为8.3%,KA油(环己醇和环己酮)的选择性为90%。与非化学计量的钙钛矿复合材料相比,纯相的LaCoO钙钛矿催化剂反应活性最高。XRD,FTIR,SEM,TEM和SAED的表征结果证实了具有小晶体尺寸的纯相LaCoO钙钛矿的形成,而XPS和EPR则表明,化学计量LaCoO表面上的具有更多的Co离子。DFT计算澄清了La离子在氧吸附中的作用,表面La有利于O分子的吸附活化。纯相的LaCoO钙钛矿表面具有较多的Co离子以及丰富的表面活性氧物种,这是其具有优异的催化活性的原因。本工作为深入理解高活性钴基催化剂的表面活性物种提供了理论指导。

关键词：环己烷部分氧化钙钛矿 LaCoO3 过渡金属催化剂构效关系

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