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热等静压烧结制备细晶粒 Ce,Y:SrHfO_(3) 闪烁陶瓷

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无机材料学报 2021年第10期36卷 1118-1124页

作者：朱丹阳钱康陈肖朴胡泽望刘欣李晓英潘裕柏 mihÓkovÁeva NIKL Martin 李江中国科学院上海硅酸盐研究所透明光功能无机材料重点实验室上海201899 中国科学院大学材料科学与光电工程中心北京100049 上海师范大学物理系上海200234 捷克科学院物理研究所捷克布拉格16200

Ce:SrHfO_(3)陶瓷因具有高密度和高有效原子序数,对高能射线具有很强的阻止能力。同时,Ce:SrHfO_(3)陶瓷还具有快衰减和高能量分辨率等优异的闪烁性能,引起了研究人员的广泛关注。由于传统的烧结方法难以实现非立方结构Ce:SrHfO_(3)陶... 详细信息

Ce:SrHfO_(3)陶瓷因具有高密度和高有效原子序数,对高能射线具有很强的阻止能力。同时,Ce:SrHfO_(3)陶瓷还具有快衰减和高能量分辨率等优异的闪烁性能,引起了研究人员的广泛关注。由于传统的烧结方法难以实现非立方结构Ce:SrHfO_(3)陶瓷的透明化,本研究采用真空长时烧结和短时真空预烧结合热等静压烧结(Hot Isostatic Pressing,HIP)方法制备Ce,Y:SrHfO_(3)陶瓷。以金属氧化物和碳酸盐为原料,1200℃下煅烧8 h可以获得平均粒径为152 nm的纯相Ce,Y:SrHfO_(3)粉体。1800℃真空烧结20 h获得平均晶粒尺寸为28.6μm的不透明的Ce,Y:SrHfO_(3)陶瓷,而两步烧结法可以制备光学透过率良好的Ce,Y:SrHfO_(3)陶瓷。本研究详细分析了陶瓷致密化过程中微结构的演变,探究了预烧结温度对Ce,Y:SrHfO_(3)陶瓷密度、显微结构和光学透过率的影响。真空预烧(1500℃×2 h)结合HIP后处理(1800℃×3 h,200 MPa Ar)所获得的Ce,Y:SrHfO_(3)陶瓷在800 nm处的最高直线透过率为21.6%,平均晶粒尺寸仅为3.4μm。在X射线激发下,Ce,Y:SrHfO_(3)陶瓷在400 nm处产生Ce3+5d-4f发射峰,其XEL积分强度比商用锗酸铋(BGO)晶体高3.3倍,Ce,Y:SrHfO_(3)陶瓷在1μs门宽下的光产额约为3700 ph/MeV。良好的光学和闪烁性能可以拓宽Ce,Y:SrHfO_(3)陶瓷在闪烁探测领域的应用。

关键词： Ce,Y:SrHfO_(3)陶瓷热等静压烧结微观结构晶粒细化闪烁性能

Antioxidant efficiency of lycopene on oxidative stress-induced damage in bovine spermatozoa

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Journal of Animal Science and Biotechnology 2017年第1期8卷 67-79页

作者： eva Tvrdá Anton kovácik eva Tusimová Dusan Paál Alica Mackovich Jakhongir Alimov Norbert Lukác Department of Animal Physiology Faculty of Biotechnology and Food Sciences Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia AgroBioTech Research Centre Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia Department of Botany and Genetics Faculty of Natural Sciences Constantine the Philosopher University in Nitra Nabbrezie mladeze 91 Nitra 94974 Slovakia Department of General Biology Faculty of Natural Sciences Gulistan State University 4th Microrayon Guliston 120100 Syrdarya Uzbekistan.

Background： Lycopene（LYC） is a natural carotenoid with powerful reactive oxygen species（ROS） scavenging activities. The aim of this study was to investigate if lycopene has the ability to reverse ROS-mediated alterations to the motility, viability and intracellular antioxidant profile of bovine spermatozoa subjected to ferrous ascorbate（Fe AA）. Spermatozoa were washed out of fresh bovine semen, suspended in 2.9 % sodium citrate and subjected to LYC treatment（0.25, 0.5, 1 or 2 mmol/L） in the presence or absence of Fe AA（150 μmol/L Fe SO4 and 750 μmol/L ascorbic acid） during a 6 h in vitro culture. Spermatozoa motion characteristics were assessed using the Sperm Vision？computer-aided sperm analysis（CASA） system. Cell viability was examined with the metabolic activity（MTT） assay,ROS generation was quantified via luminometry and the nitroblue-tetrazolium（NBT） test was applied to quantify the intracellular superoxide formation. Cell lysates were prepared at the end of the in vitro culture to investigate the intracellular activity of superoxide dismutase（SOD）, catalase（CAT）, glutathione peroxidase（GPx） as well as the concentrations of glutathione（GSH） and malondialdehyde（MDA）.Results： FeA A treatment led to a reduced spermatozoa motility（P 〈 0.001）, viability（P 〈 0.001） and a decline of the antioxidant capacity of spermatozoa（P 〈 0.001） but increased the ROS generation（P 〈 0.001）, superoxide production（P 〈 0.001） and lipid peroxidation（P 〈 0.001）. LYC administration resulted in a preservation of the spermatozoa motion parameters（P 〈 0.001）, mitochondrial activity（P 〈 0.001） and antioxidant characteristics（P 〈 0.001 with respect to SOD;P 〈 0.01 in relation to CAT; P 〈 0.05 as for GPx and GSH） with a concentration range of 1 and 2 mmol/L LYC revealed to be the most ***： Our results suggest that LYC exhibits significant ROS-scavenging and antioxidant properties which may prevent spermatozoa alterations caused by oxidative stress, and preserve the functional

关键词： Antioxidants Bulls Ferrous ascorbate Lycopene Oxidative stress Spermatozoa

Role of forests in headwater control with changing environment and society

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International Soil and Water Conservation Research 2021年第1期9卷 143-157页

作者： Josef Krecek Jana Nováková Ladislav Palán eva Pazourková Evzen Stuchlík Department of Hydrology Czech Technical University in PragueThákurova 7CZ-16629Prague 6Czech Republic Independent Botanist Na Vrcholu 4CZ-13000PragueCzech Republic AON Impact Forecasting Václavskénáměstí19CZ-11000PragueCzech Republic Institute of Hydrobiology Biology CentreCzech Academy of SciencesNa Sádkách 7CZ-37005(C)eskéBudějoviceCzech Republic

Forest practices in headwater catchments are related to environmental and social *** aim of this study is to analyse the changing protective functions of forests in the upper plain of the Jizera Mts.(North Bohemia,Czech Republic)since the second half of the 19th *** time,forests have gradually changed from native stands to spruce plantations(Picea abies),introducing exotic conifers(more resistant to air pollution),and,recently,back to more diverse mixed *** priority in pro-tective forest functions there shifted from flood protection to integrated control of water resources(quantity and quality).In the 1980s,forest-water interactions were degraded by consequences of extreme acid atmospheric deposition,forest die-back,and extensive *** the Jizerka catchment,first signs of recovery were observed in the early *** waters there are still affected by prolonged *** reconstruction of stream water chemistry at Jizerka follows the drop of the acid deposition in some 5 years,the revival of stream biota takes 10-15 *** 2071-2100,the pro-jected climate change shows rising annual air temperatures by 3.0-4.6℃,decreasing water yield by 65-123 mm,60%drop in'minimum residual discharge',and 20-30%rise in ***,these projected environmental changes cannot substantially decline the high potential in water resource recharge,or,start reverse processes in recent recovery from acidification and radically affect the exis-tence of planned mixed forests in the upper plain of the Jizera Mts.

关键词： Headwater catchment Forest functions Water resource recharge Acid atmospheric deposition Climate change

Regulated upon activation,normal T cell expressed and secreted(RANTES)levels in the peripheral blood of patients with Alzheimer’s disease

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Neural Regeneration Research 2021年第4期16卷 775-779页

作者： Gabriela Vacínová Daniela Vejražkova Robert Rusina Iva Holmerová Hana Vaňková eva Jarolímová Josef Včelák Běla Bendlová Markéta Vaňková Department of Molecular Endocrinology Institute of EndocrinologyPragueCzech Republic Department of Anthropology and Human Genetics Faculty of ScienceCharles UniversityPragueCzech Republic Department of Neurology Third Faculty of Medicine of Charles University and Thomayer Hospital PragueCzech Republic II.Internal Medicine Clinic Third Faculty of MedicineCharles UniversityPragueCzech Republic Faculty of Humanitites Charles University PragueCzech Republic

Alzheimer’s disease(AD)is the most common type of dementia,but it is very difficult to diagnose with certainty,so many AD studies have attempted to find early and relevant diagnostic *** upon activation,normal T cell expressed and secreted(RANTES,also known as C-C chemokine ligand)is a chemokine involved in the migration of T cells and other lymphoid *** in RANTES levels and its expression in blood or in cerebrospinal fluid have been reported in some neurodegenerative diseases,such as Parkinson’s disease and multiple sclerosis,but also in metabolic diseases in which inflammation plays a *** aim of this observational study was to assess RANTES levels in peripheral blood as clinical indicators of *** levels of RANTES were investigated in 85 AD patients in a relatively early phase of AD(median 8.5 months after diagnosis;39 men and 46 women;average age 75.7 years),and in 78 control subjects(24 men and 54 women;average age 66 years).We found much higher plasma levels of RANTES in AD patients compared to controls.A negative correlation of RANTES levels with age,disease duration,Fazekas scale score,and the medial temporal lobe atrophy(MTA)score(Scheltens’s scale)was found in AD patients,i.e.,the higher levels corresponded to earlier stages of the *** RANTES levels were not correlated with cognitive *** AD patients,RANTES levels were positively correlated with the levels of pro-inflammatory cytokines interleukin-6 and tumor necrosis factor-α,which is consistent with the wellknown fact that AD is associated with inflammatory *** levels were also positively correlated with insulin levels in AD patients,with insulin resistance(HOMA-R)and pancreatic beta cell function(HOMA-F).This study evaluated several clinical and metabolic factors that may affect plasma levels of RANTES,but these factors could not explain the increases in RANTES levels observed in AD *** levels of RANTES appear to be an interesting

关键词： Alzheimer’s disease biomarker central nervous system cognitive impairment inflammation RANTES

Novel approaches in schizophrenia-from risk factors and hypotheses to novel drug targets

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World Journal of Psychiatry 2021年第7期11卷 277-296页

作者： MatejĽupták Danica Michaličková Zdeněk Fišar eva Kitzlerová Jana Hroudová Institute of Pharmacology First Faculty of MedicineCharles University and General University Hospital in PraguePrague 12800Czech Republic Department of Psychiatry First Faculty of MedicineCharles University and General University Hospital in PraguePrague 12000Czech Republic

Schizophrenia is a severe psychiatric disorder characterized by emotional,behavioral and cognitive disturbances, and the treatment of schizophrenia is oftencomplicated by noncompliance and pharmacoresistance. The search for thepathophysiological mechanisms underlying schizophrenia has resulted in theproposal of several hypotheses to explain the impacts of environmental, genetic,neurodevelopmental, immune and inflammatory factors on disease onset andprogression. This review discusses the newest insights into the pathophysiologyof and risk factors for schizophrenia and notes novel approaches in antipsychotictreatment and potential diagnostic and theranostic biomarkers. The currenthypotheses focusing on neuromediators (dopamine, glutamate, and serotonin),neuroinflammation, the cannabinoid hypothesis, the gut-brain axis model, andoxidative stress are summarized. Key genetic features, including small nucleotidepolymorphisms, copy number variations, microdeletions, mutations andepigenetic changes, are highlighted. Current pharmacotherapy of schizophreniarelies mostly on dopaminergic and serotonergic antagonists/partial agonists, butnew findings in the pathophysiology of schizophrenia have allowed theexpansion of novel approaches in pharmacotherapy and the establishment ofmore reliable biomarkers. Substances with promising results in preclinical andclinical studies include lumateperone, pimavanserin, xanomeline, roluperidone,agonists of trace amine-associated receptor 1, inhibitors of glycine transporters,AMPA allosteric modulators, mGLUR2-3 agonists, D-amino acid oxidase inhibitorsand cannabidiol. The use of anti-inflammatory agents as an add-on therapy ismentioned.

关键词： Schizophrenia Immune system Inflammation Genetics Novel antipsychotics Add-on therapy

Making the Genotypic Variation Visible:Hyperspectral Phenotyping in Scots Pine Seedlings

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Plant Phenomics 2023年第4期5卷 790-804页

作者： Jan Stejskal Jaroslav Čepl eva Neuwirthová Olusegun Olaitan Akinyemi Jiří Chuchlík Daniel Provazník Markku Keinänen Petya Campbell Jana Albrechtová Milan Lstiburek Zuzana Lhotáková Department of Genetics and Physiology of Forest Trees Faculty of Forestry and Wood SciencesCzech University of Life Sciences PraguePragueCzech Republic Department of Environmental and Biological Sciences University of Eastern FinlandJoensuuFinland Department of Experimental Plant Biology Charles UniversityPragueCzech Republic Center for Photonic Sciences University of Eastern FinlandJoensuuFinland Department of Geography and Environmental Sciences University of Maryland Baltimore CountyBaltimoreMDUSA Biospheric Sciences Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA

Hyperspectral reflectance contains valuable information about leaf functional traits,which can indicate a plant's physiological ***,using hyperspectral reflectance for high-throughput phenotyping of foliar traits could be a powerful tool for tree breeders and nursery practitioners to distinguish and select seedlings with desired adaptation potential to local *** evaluated the use of 2 nondestructive methods(i.e.,leaf and proximal/canopy)measuring hyperspectral reflectance in the 350-to 2,500-nm range for phenotyping on 1,788 individual Scots pine seedlings belonging to lowland and upland ecotypes of 3 different local populations from the Czech ***-level measurements were collected using a spectroradiometer and a contact probe with an internal light source to measure the biconical reflectance factor of a sample of needles placed on a black background in the contact probe field of *** proximal canopy measurements were collected under natural solar light,using the same spectroradiometer with fiber optical cable to collect data on individual seedlings'hemispherical conical reflectance *** latter method was highly susceptible to changes in incoming *** spectral datasets showed statistically significant differences among Scots pine populations in the whole spectral ***,using random forest and support vector machine learning algorithms,the proximal data obtained from the top of the seedlings offered up to 83%accuracy in predicting 3 different Scots pine *** conclude that both approaches are viable for hyperspectral phenotyping to disentangle the phenotypic and the underlying genetic variation within Scots pine seedlings.

关键词： Scots forest reflectance

Mesenchymal stem cells for the treatment of tendon disorders

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Journal of Biomedical Science and Engineering 2013年第8期6卷 14-23页

作者： Lucia Machová Urdzíková Petr Lesny eva Syková Pavla Jendelová Institute of Experimental Medicine Academy of Sciences of the Czech Republic Prague Czech Republic Institute of Experimental Medicine Academy of Sciences of the Czech Republic Prague Czech Republic Department of Neuroscience Second Faculty of Medicine Charles University Prague Czech Republic

Tendon disorders are associated with increased morbidity and a reduction in the quality of life, especially in people of working age. Recently, a new approach, cell-based therapy, offers promising potential to treat tendon injuries. Mesenchymal stem cells are the most suitable candidates for such therapies due to their capacity to differentiate into cells of mesodermal origin, their paracrine properties and their potential use in autologous transplantation. This review summarizes experimental as well as clinical data focusing on the use of mesenchymal stem cells to treat tendinophaties.

关键词： Tendinophaty Tendinosis Tendonitis Models of Tendon Injuries Mesenchymal Stem Cells Rotator Cuff Achilles Tendon Tendon Rupture

Geodetic Monitoring of the Surface within the Trial Operation of the Room and Pillar Mining Method in the Ostrava-Karvina Coal District

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International Journal of Clean Coal and Energy 2016年第2期5卷 37-44页

作者： eva Jiránková Jitka Mučková Petr Jadviščok Robert Vochta Vlastimil Molčák Martina Havlicová VSB-Technical University Ostrava Czech Republic Survey and Geology Manager OKD A.S. Mine Plant 2 Stonava Czech Republic

Mine Plant 2 is a part of the Ostrava-Karvina Coal District (OKD) that is located in the Czech part of the Upper Silesian Basin. The first coal was exhausted from Mine Plant 2 in 1968. The most used method of mining so far in this area has been strike longwall mining with controlled caving. Due to extensive changes in the surface, which occur as a consequence of deep mining by the method of longwall mining with controlled caving, it is not possible to use this method in densely populated areas. At the present time, therefore, the trial operation of a new mining method called room and pillar is carried out. The method was chosen with the aim to minimize subsidence and deformations of the surface. The room and pillar mining method has never been used before in the conditions of the OKR, therefore it is necessary to prove the real effect of mining by this method on the surface. For this purpose, a surface observation station was designed, consisting of 36 surface points. The position and height of all points of the observation station is determined in stages three times a year.

关键词： Surface Subsidence Room and Pillar Protective Pillar of the Shaft

Celiac disease markers in patients with liver diseases: A single center large scale screening study

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World Journal of Gastroenterology 2012年第43期18卷 6255-6262页

作者： Pavel Drastich eva Honsová Alena Lodererová Marcela Jaresová Aneta Pekáriková Iva Hoffmanová Ludmila Tuková Helena Tlaskalová-Hogenová Julius piák Daniel Sánchez Department of Hepatogastroenterology Institute for Clinical and Experimental Medicine 14021 Prague Czech Republic Department of Clinical and Transplant Pathology Institute for Clinical and Experimental Medicine 14021 Prague Czech Republic Department of Immunology Institute for Clinical and Experimental Medicine 14021 Prague Czech Republic Department of Immunology Institute of Microbiology Academy of Sciences of the Czech Republic 14220 Prague Czech Republic 2nd Department of Internal Medicine 3rd Faculty of Medicine Charles University 10034 Prague Czech Republic

AIM:To study the coincidence of celiac disease, we tested its serological markers in patients with various liver ***:Large-scale screening of serum antibodies against tissue transglutaminase (tTG), and deamidated gliadin using enzyme-linked immunosorbent assay and serum antibodies against endomysium using immunohistochemistry, in patients with various liver diseases (n = 962) and patients who underwent liver transplantation (OLTx, n = 523) was performed. The expression of tTG in liver tissue samples of patients simultaneously suffering from celiac disease and from various liver diseases using immunohistochemistry was carried out. The final diagnosis of celiac disease was confirmed by histological analysis of small-intestinal biopsy. RESULTS:We found that 29 of 962 patients (3%) with liver diseases and 5 of 523 patients (0.8%) who underwent OLTx were seropositive for IgA and IgG anti-tTG antibodies. However, celiac disease was biopsy-diagnosed in 16 patients:4 with autoimmune hepatitis type Ⅰ, 3 with Wilson's disease, 3 with celiac hepatitis, 2 with primary sclerosing cholangitis, 1 with primary biliary cirrhosis, 1 with Budd-Chiari syndrome, 1 with toxic hepatitis, and 1 with non-alcoholic steatohepatitis. Unexpectedly, the highest prevalence of celiac disease was found in patients with Wilson's disease (9.7%), with which it is only rarely associated. On the other hand, no OLTx patients were diagnosed with celiac disease in our study. A pilot study of the expression of tTG in liver tissue using immunohistochemistry documented the overexpression of this molecule in endothelial cells and periportal hepatocytes of patients simultaneously suffering from celiac disease and toxic hepatitis, primary sclerosing cholangitis or autoimmune hepatitis type Ⅰ. CONCLUSION:We suggest that screening for celiac disease may be beneficial not only in patients with associated liver diseases, but also in patients with Wilson's disease.

关键词： Tissue transglutaminase Anti-tissue transglutaminase antibodies Autoimmune liver diseases Wilson's disease Celiac disease Liver transplantation