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由Mg-Fe(Ⅱ)-Fe(Ⅲ) LDH层状前体制备MgFe_2O_4尖晶石的研究

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化学学报 2003年第1期61卷 51-57页

作者：刘俊杰李峰 EVANS D.g 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

提出了一种由层状前体合成单一晶相镁铁尖晶石的新方法,首先对Mg Fe(Ⅱ) Fe(Ⅲ)水滑石的制备进行了系统研究,成功合成了Mg2 +/Fe2 +/Fe3+摩尔比分别为 1/2/1,4/5/3,2/1/1的系列水滑石层状前体,结果表明在以上三种投料比下均可制备出晶... 详细信息

提出了一种由层状前体合成单一晶相镁铁尖晶石的新方法,首先对Mg Fe(Ⅱ) Fe(Ⅲ)水滑石的制备进行了系统研究,成功合成了Mg2 +/Fe2 +/Fe3+摩尔比分别为 1/2/1,4/5/3,2/1/1的系列水滑石层状前体,结果表明在以上三种投料比下均可制备出晶型较好的水滑石层状前体,并探讨了合成条件对晶体结构的影响规律.在此基础上,利用X射线衍射、振动样品磁强计和穆斯堡尔谱等手段研究了层状前体焙烧产物的结构、组成、磁性及微观信息,研究表明当Mg2 +/Fe2 +/Fe3+投料摩尔比为 2/1/1时。

关键词： MgFe2O4尖晶石镁铁铁水滑石共沉淀磁性铁氧体软磁材料

The cholera epidemic of 2004 in Douala, Cameroon: A lesson learned

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Asian Pacific Journal of Tropical Medicine 2019年第8期12卷 347-352页

作者： Christoph J.Hemmer Jürgen Noske Stefan Finkbeiner günter Kundt Emil C.Reisinger University of Rostock Faculty of MedicineDepartment of Tropical Medicine and Infectious DiseasesRostockGermany gesellschaft für Internationale Zusammenarbeit YaoundéCameroon University of Rostock Faculty of MedicineInstitute of Biostatistics and Informatics in Medicine and Ageing ResearchRostockGermany

Objective: To describe the outbreak of 2004 with a view of retrospectively identifying factors that might explain the low case fatality rate. Methods: Outbreak data from 4 915 Cholera patients from registers of the Regional Health Delegation in Douala were analyzed using SPSS. Chi-square test, univariate and multivariate analysis were applied. Results: The outbreak started January 2004, peaking at 187 cases per week in February. After a decrease in April, case numbers rose to 688 cases per week in June. The outbreak was over in September 2004( gher in treatment centers with fewer than one nurse per two patients, than in those with more nursing staff. A temporary staff reduction after the first wave of the epidemic was associated with the increase of the case fatality rate during the second wave. This increase was reversed after re-instating full staff ***: Providing sufficient nursing staff helps to lower the case fatality rate of cholera. Besides a lack of staff, age above 40 years is a risk factor for death in this disease.

关键词： Cholera Douala Cameroon Case fatality rate Staff-to-patients ratio

The off-host survival and viability of a native and non-native fish louse （Argulus, Crustacea： Branchiura）

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Current Zoology 2011年第6期57卷 828-835页

作者： P.D. WALKER I.J. RUSSON R. DUIJF g. VAN DER VELDE S.E. WENDELAAR BONgA Radboud University of Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands APEM Ltd Centre for Innovation ＆ Enterprise Begbroke Science Park Sandy Lane Yarnton Oxfordshire OX5 1PF United Kingdom Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 2300 RA Leiden The Netherlands

Fish ectoparasites are introduced to water bodies or aquaculture systems along with their hosts. Argulid fish lice can survive off-host for a given time, and in spite of quarantine measures might also be introduced via the transfer of water. However, they must cope with varying abiotic conditions without access to food. We investigated the effect of temperature （5 to 28℃） on the off-host survival time of Argulus japonicus, an invasive species which is apparently increasing its distribution, and compared this with the European A. foliaceus. A clear effect of temperature on the off-host survival time of all stages of both species was demonstrated. Larval and juvenile A. japonicus survived up to 9 days at 22℃ and in the case of adults up to 13 days at 15℃. By comparison, larval A. foliaceus survived up to 5 days at 15℃, adults up to 14 days at 9℃ and juveniles up to 7 days at 9℃ and 15℃. Thus, A. japonicus is more resistant to starvation at higher temperatures under controlled off-host conditions and A. foli- aceus is more resistant to starvation at lower temperatures. Infectivity of A. japonicus decreased linearly with the time spent off-host after 2 days for larvae and 4 days for adults. Temperature only had a significant effect on the infectivity of both develop- mental stages after 24 hours off-host between 13-23℃ for larvae and 13-18℃ for adults. In conclusion both species can potentially survive off-host pelods in water transports for up to 13-14 days as adults. Their survival is shorter as larvae. This study demonstrates that transportation of water has the potential to introduce Argulus species

关键词： Argulus Fish lice Survival Temperature Off-host Water transport Introductions Invasive species

A new paradigm for diagnosis of neurodegenerative diseases: peripheral exosomes of brain origin

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Translational Neurodegeneration 2022年第1期11卷 532-546页

作者： Neelam Younas Leticia Camila Fernandez Flores Franziska Hopfner günter U.Höglinger Inga Zerr Prion Research group Department of NeurologyNational Reference Center for Surveillance of TSEUniversitätsklinikum Göttingen:Universitätsmedizin GöttingenGeorg-August UniversityGöttingenGermanyRobert-Koch-Strasse 4037075 GöttingenGermany Hannover Medical School Medizinische Hochschule HannoverHannoverGermany german Center for Neurodegenerative Diseases(DZNE) MunichGermany german Center for Neurodegenerative Diseases(DZNE) GöttingenGermany.

Neurodegenerative diseases are a heterogeneous group of maladies, characterized by progressive loss of neurons. These diseases involve an intricate pattern of cross-talk between different types of cells to maintain specific signaling pathways. A component of such intercellular cross-talk is the exchange of various types of extracellular vesicles (EVs). Exosomes are a subset of EVs, which are increasingly being known for the role they play in the pathogenesis and progression of neurodegenerative diseases, e.g., synucleinopathies and tauopathies. The ability of the central nervous system exosomes to cross the blood-brain barrier into blood has generated enthusiasm in their study as potential biomarkers. However, the lack of standardized, efficient, and ultra-sensitive methods for the isolation and detection of brain-derived exosomes has hampered the development of effective biomarkers. Exosomes mirror heterogeneous biological changes that occur during the progression of these incurable illnesses, potentially offering a more comprehensive outlook of neurodegenerative disease diagnosis, progression and treatment. In this review, we aim to discuss the challenges and opportunities of peripheral biofluid-based brain-exosomes in the diagnosis and biomarker discovery of Alzheimer’s and Parkinson’s diseases. In the later part, we discuss the traditional and emerging methods used for the isolation of exosomes and compare their advantages and disadvantages in clinical settings.

关键词： Alzheimer’s disease Central nervous system Diagnosis Exosomes Blood-brain barrier Parkinson’s disease

Electrophoretic deposition of silk fibroin coatings with pre-defined architecture to facilitate precise control over drug delivery

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Bioactive Materials 2021年第11期6卷 4243-4254页

作者： Xian Cheng Dingpei Long Lili Chen John A.Jansen Sander C.g.Leeuwenburgh Fang Yang Department of Dentistry-Biomaterials Radboud Institute for Molecular Life SciencesRadboud University Medical CenterPhilips van Leydenlaan 256525EX Nijmegenthe Netherlands Jiangsu Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjing210029PR China Institute for Biomedical Sciences Center for Diagnostics&TherapeuticsGeorgia State UniversityAtlantaGA30302USA Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022PR China

The therapeutic precision and clinical applicability of drug-eluting coatings can be substantially improved by facilitating tunable drug ***,the design of coatings which allows for precise control over drug release kinetics is still a major ***,a double-layered silk fibroin(SF)coating system was constructed by sequential electrophoretic deposition.A mixture of dissolved Bombyx mori SF(bmSF)molecules and pre-made bmSF nanospheres at different ratios was deposited as ***,this underlayer was covered by a top-layer comprising Antheraea pernyi SF(apSF)molecules(rich in arginylglycylaspartic acid,RgD)to improve the cellular response of the resulting double-layered ***,model drug doxycycline was either pre-mixed with dissolved bmSF molecules or pre-loaded into pre-made bmSF nanospheres at the same amount before their mixing and *** thickness and nanosphere content of the under-layer architecture were proportional to the deposition time and nanosphere concentration in precursor mixtures,*** surface topography,wettability,degradation rate and adhesion strength were comparable within the double-layered coating *** expected,RgD-rich apSF top-layer improved cell adhesion,spreading and proliferation compared with bmSF ***,the amount and duration of drug release increased linearly with increasing nanosphere concentration at fixed deposition time,whereas drug release amount increased linearly with increasing deposition *** results indicate that the dosage and kinetics of loaded drugs can be quantitatively tailored by altering nanosphere concentration and deposition time as main processing ***,this study illustrates the strong potential of pre-defining coating architecture to facilitate control over drug delivery.

关键词： Electrophoretic deposition Coating Drug delivery kinetics Silk fibroin Nanospheres

Signal or cue: the role of structural colors in flower pollination

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Current Zoology 2019年第4期65卷 467-481页

作者： Jair E. garcia Mani Shrestha Scarlett R. Howard Phred Petersen Adrian g. Dyer School of Media and Communication RMIT University Melbourne Victoria 3001 Australia Faculty of Information Technology Monash University Clayton Victoria 3800 Australia

Angle dependent colors, such as iridescenee, are produced by structures present on flower petals changing their visual appearanee. These colors have been proposed to act as signals for plantinsect communication. However, there is a paucity of behavioral data to allow for interpretations of how to classify these colors either as a signal or a cue when con sidering the n atural con ditions under which pollination occurs. We sampled flowers from 6 plant species across various viewpoints looking for changes in the visual appearanee of the petals. Spectral characteristics were measured with different instruments to simulate both the spectral and spatial characteristics of honeybee's vision. We show the presenee of color patches produced by angle dependent effects on the petals and the calyx of various species;however, the appearance of the angle dependent color patches significantly varies with viewpoint and would only be resolved by the insect eye at close distances. Behavior experiments with honeybees revealed that pollinators did not use angle dependent colors to drive behavior when presented with novel flower presentations. Results show that angle dependent colors do not comply with the requirements of a signal for plant-pollinator communication since the information transmitted by these colors would be unreliable for potential, free-flying pollination vectors. We thus classify angle dependent colors produced by micro- and ultra-structures as being a cue (a feature which has not evolved for communication), and observe no evidence supporting claims of these angle dependent colors having evolved as visual signal.

关键词： approach angle color flower iridescence photography pollination vision

TURNINg A CORNER: Kansas State University Seeks to Meaningfully Address green Building and the Sustainable Use of Energy and Resources on Campus and in the Broader Community

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Journal of green Building 2010年第4期5卷 34-66页

作者： Lee R.Skabelund R.Todd gabbard Barbara g.Anderson Benjamin L.Champion LA/RCP(Landscape Architecture) College of ArchitecturePlanning&DesignKansas State UniversitySeaton Hall 303IManhattan66506 Architecture College of ArchitecturePlanning&DesignKansas State University211 Seaton HallManhattan66506 ATID(Interior Design) College of Human EcologyKansas State University218 Justin HallManhattan66506. Director of Sustainability Provost OfficeKansas State University258 Leadership Studies BuildingManhattan66506.

Kansas State University(KSU)is a land-grant institution,with nine colleges and 23,000 *** 668-acre main campus is located within the City of Manhattan,Kansas,which has a population of approximately 45,*** a bottom-up process the university has been seeking to integrate sustainability in student life,curriculum,operations,research,and engagement.

关键词： college sustainability collaborative design energy efficiency stormwater management solar power green roofs material re-use

Cholecystectomy for asymptomatic gallstones:Markov decision tree analysis

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World Journal of Clinical Cases 2022年第29期10卷 10399-10412页

作者： Brian Juin Hsien Lee Qai Ven Yap Jee Keem Low Yiong Huak Chan Vishal g Shelat Lee Kong Chian School of Medicine Nanyang Technological UniversitySingapore S308232Singapore Biostatistics Unit Yong Loo Lin School of MedicineNational University of SingaporeSingapore S117597Singapore Department of general Surgery Tan Tock Seng HospitalSingapore S308433Singapore

gallstones are a common public health problem,especially in developed *** are an increasing number of patients who are diagnosed with gallstones due to increasing awareness and liberal use of imaging,with 22.6%-80% of gallstone patients being asymptomatic at the time of *** being asymptomatic,this group of patients are still at life-long risk of developing symptoms and complications such as acute cholangitis and acute biliary ***,while early prophylactic cholecystectomy may have some benefits in selected groups of patients,the current standard practice is to recommend cholecystectomy only after symptoms or complications *** reviewing the current evidence about the natural course of asymptomatic gallstones,complications of cholecystectomy,quality of life outcomes,and economic outcomes,we recommend that the option of cholecystectomy should be discussed with all asymptomatic gallstone *** of material information is essential for patients to make an informed choice for prophylactic *** is for the patient to decide on watchful waiting or prophylactic cholecystectomy,and not for the medical community to make a blanket policy of watchful waiting for asymptomatic gallstone *** patients with high-risk profiles,it is clinically justifiable to advocate cholecystectomy to minimize the likelihood of morbidity due to complications.

关键词： Asymptomatic Cholecystectomy Cholelithiasis gallbladder gallstone