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In situ differential scanning calorimetry analysis of dissolution and precipitation kinetics in Mg-Y-RE alloy WE43

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Journal of Magnesium and Alloys 2019年第1期7卷 1-14页

作者： Benjamin Milkereit Lydia Burgschat Richard H.Kemsies Armin Springer Christoph Schick Olaf Kessler Chair of Materials Science Faculty of Mechanical Engineering and Marine TechnologyUniversity of RostockGermany Competence centreCALOR-Calorimetry and Thermal Analysis Rostock Department LifeLight&MatterInterdisciplinary FacultyUniversity of RostockGermany medical biology and electron microscope centre University Medical Centre RostockGermany Institute of Physics Polymer Physics GroupUniversity of RostockGermany

Further development of our differential scanning calorimetry(DSC)method for the analysis of solid-solid phase transformations now also allows for its application in the kinetic analysis of age hardening in Mg *** a result,the state-of-the-art for DSC on Mg alloys has been improved with respect to the accessible temperature range,zero-level accuracy and dynamic *** analysis was performed on the example of Mg wrought alloy *** DSC experiments on the initial condition T4 and even direct continuous cooling DSC analysis on the kinetics of quench induced precipitation during cooling from solution treatment were possible,covering a dynamic range of 0.01-3 K/*** DSC findings are discussed with respect to literature knowledge and scanning electron microscopy analysis of the defined heat treatment states.

关键词： Precipitation Dissolution Kinetics DSC Magnesium alloy WE43 SEM Quench induced precipitation Continuous cooling

Decline and fall of aging astrocytes:the human perspective

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Neural Regeneration Research 2025年第6期20卷 1713-1714页

作者： Alexei Verkhratsky Alexey Semyanov Faculty of biology Medicine and HealthThe University of ManchesterManchesterUK Department of Neurosciences University of the Basque Country UPV/EHU and CIBERNEDLeioaSpain Department of Forensic Analytical Toxicology School of Forensic MedicineChina Medical UniversityShenyangLiaoning ProvinceChina Department of Stem Cell biology State Research Institute Centre for Innovative MedicineVilniusLithuania International Collaborative Center on Big Science Plan for Purinergic Signalling Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina Department of Physiology Jiaxing University College of MedicineJiaxingZhejiang ProvinceChina

“Last scene of all that ends this strange,eventful history,is second childishness and mere oblivion.I am sans teeth,sans eyes,sans taste,sans everything.”William Shakespeare‘As You Like It'Act 2,Sc.7,l.139Aging of the human brain is characterized by a progressive decline of its functional capacity;this decline however varies widely,and cognitive longevity differs substantially between individuals.

关键词： aging teeth progressive

Diflubenzuron inhibits reproduction of different strains of Drosophila melanogaster

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Insect Science 2009年第4期16卷 305-309页

作者： Zbigniew Adamski Jerzy Bloszyk Jakub Musiat Marta Lysiak Lech Urbaniak Kazimierz Ziemnicki Department of Animal Physiology and Developmental biology Laboratory of electron and Confocal microscope Department of General Zoology Natural History Collection Department of Genetics Adam Mickiewicz University Poznan Poland

The effect of （1-（4-chlorophenyl）-3-（2,6-difluorobenzoyl）urea） insecticide - diflubenzuron - on wild type and white type fruit flies Drosophila melanogaster （Meigen, 1830） was studied. Adult insects were placed in vials with different concentrations of the insecticide in the nutrient （from 0.048 to 48 mg of diflubenzuron per 1 cm^3 of the nutrient）. In each case, the insects showed some mortality, which was concentrationdependant. When comparing both strains, we could observe different acute toxicities, with wild type being more resistant to diflubenzuron. However, subacute toxicity was similar within both strains. In both strains the prolonged exposure led to the extinction of the majority of the populations （〉 70%）. Although imagoes could freely copulate, we did not observe copulating fruit flies, and we did not find either eggs or larvae in any of the exposed groups. These results indicate that genetic mutation which leads to different eye colour can also affect resistance and survival of insects in pesticide-exposed areas.

关键词： diflubenzuron dimilin fruit flies pesticides reproduction toxicity

Ultrastructural and immunohistochemical studies on Trichomonas vagi nalis adhering to and phagocytizing genitourinary epithelial cells

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Chinese medical Journal 2004年第3期117卷 376-381页

作者：陈文列陈金富钟秀容梁平林炜 Fujian medical University Laboratory of electron Microscopy Fujian medical University Department of Parasitology Fujian medical University Department of Cell biology

Background Trichomonas vaginalis (T. vaginalis ) belongs to a common sexually transmitted disease pathogen causing genitourinary trichomoniasis in both sexes. We investigated the pathogenetic mechanism of gen itourinary *** Cultured T. vaginalis bodies were injected into the vaginas of rats, or incubated with genitourinary epithelial cells of female subjects, male subjects, and sperm. The ultrastructural and microscopic changes were observed via transmission and scanning electron microscopy and through microscopic *** Groups of *** adhered to PAS positive colum nar cells at the surface of stratified epithelium in the middle and upper portions of the vaginas. They a lso traversed under these cells. The parasites were shown to be PAS, cathepsin D, and actin positive, and they could release hydrolase into the cytoplasm of adher ed epithelial cells. In the amebiform ***, microfilaments were arranged into reticular formation. Similar phenomena were found during the interaction of *** with host cells, both in vitro and in vivo. Usually several protozoa adhered to a n epithelial cell and formed polymorphic pseudopodia or surface invaginations to surround and phagocytize the microvilli or other parts of the epithelial cytoplasm. Adhesion and phagocytosis of sperm by the protozoa occurred at 15-30 minutes of incubation. Digestion of sperm was found at 45-75 minutes and was complete at 90-105 *** *** tends to parasitize at the fornix o f the vagina, because this is the site where columnar cells are rich in mucinogen granules and thei r microvilli are helpful for adhesion and nibbling. *** possesses some invad ing and attacking abilities. Shape change, canalization, encystation, phagocytosis, digestion, the cell coat, cytoskeleton, and lysosome all play important roles in the process of adhesion. They have two methods of phagocytosis: nibbling and ingestion. Genitourinary epithelium

关键词： Trichomonas vaginalis · urogenital system · hydrolase · pathogenesis · microscopy electron · immunohistochemistry · histocytochemistry

The Ultrastructure of a Chlamydomonas reinhardtii Mutant Strain Lacking Phytoene Synthase Resembles that of a Colorless Alga

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Molecular Plant 2008年第6期1卷 925-937页

作者： William Inwood Corinne Yoshihara Reena Zalpuri Kwang-Seo Kim Sydney Kustu Department of Plant and Microbial biology 111 Koshland Hall University of California Berkeley CA 94720-3102 USA electron microscope Laboratory 26 Giannini Hall University of California Berkeley CA 94720-3330 USA

Chlamydomonas reinhardtii strains lacking phytoene synthase, the first enzyme of carotenoid biosynthesis, are white. They lack carotenoid pigments, have very low levels of chlorophyll, and can grow only heterotrophically in the dark. Our electron and fluorescence microscopic studies showed that such a mutant strain （Itsl-204） had a proliferated plastid envelope membrane but no stacks of thylakoid membranes within the plastid. It accumulated cytoplasmic compartments that appeared to be autophagous vacuoles filled with membranous material. The Its1 mutants apparently lacked pyrenoid bodies, which normally house ribulose bisphosphate carboxylase-oxygenase （Rubisco）, and accumulated many starch granules. Although these mutant strains cannot synthesize the carotenoid and carotenoid-derived pigments present in the phototactic organelle （eyespot）, the mutant we examined made a vestigial eyespot that was disorganized and often mislocalized to the posterior end of the cell. The absence of a pyrenoid body, the accumulation of starch, and the disorganization of the eyespot may all result from the absence of thylakoids. The ultrastructure of Its1 mutant strains is similar to but distinct from that of previously described white and yellow mutant strains of C. reinhardtii and is similar to that of naturally colorless algae of the Polytoma group.

关键词： Ultrastructure Phytoene carotenoid biosynthesis

Charge transfer between biogenic jarosite derived Fe^3＋ and TiO2 enhances visible light photocatalytic activity of TiO2

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Journal of Environmental Sciences 2017年第4期29卷 256-267页

作者： Mahabubur Chowdhury Sipiwe Shoko Fransciuos Cummings Veruscha Fester Tunde Victor Ojumu Flow Process and Rheolofy centre Cape Peninsula University of Technology South Africa Department of Chemical Engineering Cape Peninsula University of Technology South Africa electron microscope Unit University of the Western Cape South Africa

In this work, we have shown that mining waste derived Fe^3＋can be used to enhance the photocatalytic activity of TiO2. This will allow us to harness a waste product from the mines, and utilize it to enhance TiO2 photocatalytic waste water treatment efficiency. An organic linker mediated route was utilized to create a composite of TiO2 and biogenic jarosite. Evidence of Fe／O／Ti bonding in the TiO2/jarosite composite was apparent from the FTIR, EFTEM, EELS and ELNEFS analysis. The as prepared material showed enhanced photocatalytic activity compared to pristine TiO2, biogenic jarosite and mechanically mixed sample of jarosite and TiO2 under both simulated and natural solar irradiation. The prepared material can reduce the electrical energy consumption by 4 times compared to pristine P25 for degradation of organic pollutant in water. The material also showed good recyclability. Results obtained from sedimentation experiments showed that the larger sized jarosite material provided the surface to TiO2 nanoparticles, which increases the settling rate of the materials. This allowed simple and efficient recovery of the catalyst from the reaction system after completion of photocatalysis. Enhanced photocatalytic activity of the composite material was due to effective charge transfer between TiO2 and jarosite derived Fe^3＋as was shown from the EELS and ELNEFS. Generation of OHU was supported by photoluminesence（PL） experiments.

关键词： Biogenic jarosite TiO2 photocatalysis Charge transfer Organic pollutant Visible light responsive Water treatment

Angiogenic markers endoglin and vascular endothelial growth factor in gastroenteropancreatic neuroendocrine tumors

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World Journal of Gastroenterology 2011年第2期17卷 219-225页

作者： Patricia Kuiper Lukas JAC Hawinkels Eveline SM de Jonge-Muller Izk Biemond Cornelis BHW Lamers Hein W Verspaget Department of Gastroenterology and Hepatology Leiden University Medical Centre Department of Molecular Cell biology and centre for Biomedical Genetics Leiden University Medical Centre

AIM:To investigate the expression and potential prognostic role of vascular endothelial growth factor(VEGF) and endoglin in gastroenteropancreatic neuroendocrine tumors(GEP-NETs) . METHODS:Microvessel density(MVD) in GEP-NETs was evaluated using endoglin and CD31 *** addition,tissue levels of endoglin and VEGF were determined in homogenates by ELISA. RESULTS:Endoglin was highly expressed on tumor endothelial ***31 MVD in GEP-NETs was significantly higher compared to endoglin MVD(P<0.01) .Two-tofour-fold higher tissue levels of endoglin and VEGF were seen in tumors compared to associated normal tissue. This increased endoglin tissue expression in tumors was significantly related to tumor size(P<0.01) ,presence of metastases(P=0.04) ,and a more advanced tumor stage(P=0.02) ,whereas expression of VEGF was not. CONCLUSION:We suggest that endoglin is a potential marker to indicate and predict metastases,which might be useful in the post-resection therapeutic approach of patients with GEP-NETs.

关键词： Neuroendocrine tumor Carcinoid tumor Angiogenesis factors Endoglin Vascular endothelial growth factor

Reticulate spore ornamentation in Strobilomyces

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菌物学报 2011年第6期30卷 901-911页

作者： Ronald H.Petersen John Dunlap Karen W.Hughes Department of Ecology and Evolutionary biology University of TennesseeKnoxvilleTN 37996-1100USA electron microscope Facility Division of BiologyUniversity of TennesseeKnoxvilleTN 37996-0830USA

Reticulate spore ornamentation in Strobilomyces(Boletaceae,Basidiomycotina) is visible under light microscopy(bright field and phase contrast) up to 1,500×.While some distinctions can be made at this magnification,ontogeny and fine structure of the ornamentation cannot be *** electron microscope images,conversely,reveal significant additional structure from which the ontogenetic process can be *** numerous New and Old World collections,this paper presents evidence distinguishing reticulate ornamentation ontogeny in these disjunct populations.

关键词：网状孢子电子显微镜观察菌物学

Nanosized Cu-Li glass

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Science Bulletin 2018年第18期63卷 1173-1174页

作者： Peng Gao International Center for Quantum Materials Peking University Beijing 100871 China electron microscope Laboratory School of Physics Peking University Beijing 100871 China Collaborative Innovation centre of Quantum Matter Beijing 100871 China

Amorphous metallic alloy (also known as metallic glass) was firstly discovered in the 1960s as a‘‘young"member of the amorphous material family [1]. Their unique metastable disordered structure imparts metallic glasses many fascinating properties and features such as high elasticity and high strength, excellent wave-absorption ability and ultralow elastic moduli [2,3]. In general, the formation of an amorphous alloying phase requires a relatively large negative heat of mixing between the

关键词：玻璃金属性吸收能力非结晶高弹性