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Evaluation of stereology for snow microstructure measurement and microwave emission modeling:a case study

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International Journal of Digital Earth 2021年第10期14卷 1316-1336页

作者： Jinmei Pan M.T.Durand Z.Courville B.J.Vander Jagt N.P.Molotch S.A.Margulis E.J.Kim M.Schneebeli C.Mätzler State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China School of Earth Science and Byrd Polar Research Center The Ohio State UniversityColumbusOHUSA US Army Corps of Engineers Cold Regions Research and Engineering Laboratory HanoverNHUSA Geography Department and Institute of Arctic and Alpine Research University of ColoradoBoulderCOUSA Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCAUSA Hydrospheric and Biospheric Sciences Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA WSL Institute for Snow and Avalanche Research SLF Davos DorfSwitzerland Institute of Applied Physics and Oeschger Centre for Climate Change Research University of BernBernSwitzerland

Reliablemicrostructuremeasurement of snow is a requirement for microwave radiative transfer model *** specific surface area(SSA)can be measured using stereological methods,in which snow samples are cast in the field and photographed in the *** stereology photographs manually by counting intersections of test cycloids with air-ice boundaries reduces the problems in binary *** paper is a case study to evaluate the repeatability of the manually stereology interpretation by two independent research *** further assessed how uncertainty in snow SSA influences simulated brightness temperature(TB)driven by the Microwave Emission Model of Layered Snowpacks(MEMLS),and how stereology compares to Near Infrared(NIR)camera and hand *** was obtained from two alpine snow profiles from Steamboat Springs,*** showed that stereological SSA values measured by two groups are highly consistent,and the ground radiometer measured T_(B)at 19 and 37 GHz was successfully predicted(RMSE<3.8 K);simulations using NIR SSA and hand-lens geometric grain size(Dg)measurements have larger *** conclusion was not sensitive to uncertainty in the free parameters of TB modeling.

关键词： Microwave radiometry snow stereology snow microstructure MEMLS

stereology in Materials Science

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Journal of Materials Science & Technology 1990年第4期6卷 244-249页

作者：刘国权 Department of Materials Science and Engineering University of Science and Technology Beijing100083China.

Quantitative analysis of populations having a geometric structure,which has developed into a special scientific subject called microstructology or stereology,is of great importance to the characterization and evaluation of microstructures and their evolution in various *** paper, besides a brief discussion on those topics such as the recent developments of computer assisted image analysis,mathematical morphology,and fractal analysis,will mainly focus on the scope,fundamen- tals,present status,and perspectives of classical *** case examples of its application to materials science will also be given.

关键词： stereology image analysis morphology fractal analysis

LABORATORY TRAINING ON stereology FOR UNDERGRADUATE STUDENTS OF MATERIALS SCIENCE AND ENGINEERING

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LABORATORY TRAINING ON STEREOLOGY FOR UNDERGRADUATE STUDENTS...

Stereological study of the effects of vitamin E on testis structure in rats treated with para-nonylphenol

第十三届国际体视学大会

作者： Guoquan Liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

＜正＞In materials science and engineering,metallography（ceramography,polymerography or resinography） is widely used for preparation and analysis of microstructures in metallic（ceramic,polymeric） *** the other hand, stereology is a science of estimating unbiased and quantitative data of higher dimensions from lower dimensional samples,so that providing an important and efficient tool in many applications of ***,combining with metallography（ceramography,polymerography）,stereology has become an indispensable tool to determine the amount,size,topology and other geometric characteristics of phases or microconstituents contained in the microstructure of various ***,laboratory training on stereology is necessary for all the undergraduate students of materials science and engineering.

关键词： stereology metallography ceramography undergraduate teaching laboratory training program

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Asian Journal of Andrology 2009年第4期11卷 508-516页

作者： M Soleimani Mehranjani A Noorafshan HR Momeni MH Abnosi M Mahmoodi M Anvari SM Hoseini Biology Department Arak University Arak 38156 Iran Anatomy Department Shiraz University of Medical Sciences Shiraz 71348 Iran Anatomy Department Research and Clinical Center for Infertility Shahid Sadoughi University of Medical Sciences Yazd 89195-999 Iran

This study was organized to see whether vitamin E, as a strong antioxidant, could affect the abnormalities of testis structure caused by para-nonylphenol （p-NP） during its development. A total of 32 female Wistar rats after mating were divided into four groups （n = 8）： control, vitamin E （100 mg kg^-1 per day）, p-NP （250 mg kg^-1 per day） and p-NP ＋ vitamin E. The rats were treated from the seventh day of pregnancy till the twenty-first day. After weaning, the male pups were divided into the same groups and were treated orally for 90 days. Finally, the right testis was fixed, processed, stained and studied using stereological methods. The weight and volume of testis, volume of seminiferous tubules and its diameter, thickness of the basement membrane, height of the germinal epithelium, total number of types A and B spermatogonia, spermatocyte, spermatid and Sertoli cells were significantly reduced in p-NP group when compared with other groups. Co-administration of vitamin E and p-NP compensated for the adverse effects of p-NP on the above parameters. In addition, treatment with only vitamin E caused a significant increase in diameter, basement membrane thickness and height of germinal epithelium, number of spermatogonia and spermatocytes. Co-administration of vitamin E with p-NP could prevent the adverse effects ofp-NP on the testis structure during its development.

关键词： development para-nonylphenol stereology testis vitamin E

Measure of Segments which Intersect a Convex Body from Rotational Formulae

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Acta Mathematica Sinica,English Series 2015年第2期31卷 345-352页

作者： Ximo GUAL-ARNAU Silena HEROLD-GARCA Departament de Matemàtiques-INIT Universitat Jaume I. 12071-CastellSpain Departamento de Computacin Universidad de Oriente. 90900-Santiago de CubaCuba

Classical problems in integral geometry and geometric probability involve the kinematic measure of congruent segments of fixed length within a convex body in R3. We give this measure from rotational formulae; that is, from isotropic plane sections through a fixed point. From this result we also obtain a new rotational formula for the volume of a convex body; which is proved to be equivalent to the wedge formula for the volume.

关键词： Convex body flower integral geometry stereology rotational formulae segment supportset

Quantitative (stereological) study on the spermatozoal storage capacity of epididymis in rats and monkeys

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Asian Journal of Andrology 2000年第1期2卷 73-77页

作者： Xiao-Hong WEN Zheng-Wei YANG Morphometric Research Laboratory, North Sichuan Medical College, Nanchong 637007, China. Morphometric Research Laboratory North Sichuan Medical College 234 Fujiang Road Nanchong 637007 China

Aim: To investigate the spermatozoal production rate of the testis and the spermatozoal storage capacity of the epi-didymis in monkeys and rats. Methods: The number of the late spermatids (steps 13 - 14 in the monkey or steps15 - 19 in the rat) per testis and the number of spermatozoa per epididymis were estimated in 6 normal adult monkeys(Macaca fascicularis) and 6 normal adult SD rats on 25 um-thick methacrylate-embedded sections using a contempo-rary unbiased and efficient stereological method-the optical disector. The diameter and length of the efferent ductulesand ductus epididymidis and the volume of the epididymal fluid in the tubules were also estimated. Results: The totalnumber of the late spermatids per testis was 2902 ±749 (million, x ±s) in the monkey, or 179 ±31 in the rat; thenumber of spermatozoa per epididymis was 3235 ±1835 in the monkey, or 241±76 in the rat. Conclusion: A largenumber of spermatozoa was densely packed and stored in the ductus epididymidis; the epididymal transit time for sper-matozoa was around 5 days in monkeys or 11 days in rats.

关键词： epididymis spermatids spermatozoa stereology testis

Estimation of the density of neural,glial,and endothelial lineage cells in the adult mouse dentate gyrus

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Neural Regeneration Research 2022年第6期17卷 1286-1292页

作者： Joshua D.Rieskamp Patricia Sarchet Bryon M.Smith Elizabeth D.Kirby Neuroscience Graduate Program The Ohio State UniversityColumbusOHUSA Department of Psychology The Ohio State UniversityColumbusOHUSA Department of Neuroscience The Ohio State UniversityColumbusOHUSA Chronic Brain Injury Program The Ohio State UniversityColumbusOHUSA

The dentate gyrus subregion of the mammalian hippocampus is an adult neural stem cell niche and site of lifelong *** regarding the role of adult-born neuron synaptic integration in hippocampal circuit function are framed by robust estimations of adultborn versus pre/perinatally-born neuron *** contrast,the non-neurogenic functions of adult neural stem cells and their immediate progeny,such as secretion of bioactive growth factors and expression of extracellular matrix-modifying proteins,lack similar framing due to few estimates of their number versus other prominent secretory ***,we apply immunohistochemical methods to estimate cell density of neural stem/progenitor cells versus other major classes of glial and endothelial cell types that are potentially secretory in the dentate gyrus of adult *** the cell types quantified,we found that GFAP^(+)SOX2^(+)stellate astrocytes were the most numerous,followed by CD31^(+)endothelia,GFAP-SOX2^(+)intermediate progenitors,Olig2^(+)oligodendrocytes,Iba1+microglia,and GFAP^(+)SOX2^(+)radial glia-like neural stem *** did not observe any significant sex differences in density of any cell ***,neural stem/progenitor cells were present at a similar density as several cell types known to have potent functional roles via their *** findings may be useful for refining hypotheses regarding the contributions of these cell types to regulating hippocampal function and their potential therapeutic *** experimental protocols were approved by the Ohio State University Institutional Animal Care and Use Committee(protocol#2016A00000068)on July 14,2016.

关键词： adult neurogenesis dentate gyrus endothelia glia hippocampus neural stem cell secretome stereology

Quantitative (stereological) study of incomplete spermatogenic suppression induced by testosterone undecanoate injection in rats

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Asian Journal of Andrology 2004年第4期6卷 291-297页

作者： Zheng-WeiYang YangGuo LiLin Xing-HaiWang Jian-SunTong Gui-YuanZhang MorphometricResearchLaboratory NorthSichuanMedicalCollegeNanchong637007China PhotographyStudio NanchongMedicalSchoolNanchong637000China JiangsuFamilyPlanningInstitute Nanjing210029China NationalResearchInstituteforFamilyPlanning Beijing100081China

Aim: To evaluate the key lesions in spermatogenesis suppressed partially by testosterone undecanoate (TU) treatment. Methods: Adult male SD rats were treated with vehicle or TU (19 mg/kg) injection (i.m.) every 15 days for 130 days. The numbers of all types of cells (nuclei) in the seminiferous tubules and the interstitial tissue were estimated using a contemporary stereological tool, the optical disector. Results: In response to TU treatment, the numbers of non-type B spermatogonia, type B spermatogonia and late elongated spermatids per testis were reduced to 51 %, 66 % and 14 % of the controls, respectively. The conversion ratios from type B spermatogonia to early spermatocytes and pachytene spermatocytes were not significantly affected and the ratios to the later germ cell types fell to 51 % - 65 % of the controls. Less than 1.0 % of immature round spermatids were seen sloughing into the tubule lumen, 4.0 % of elongated spermatids retained in the seminiferous epithelium, and about half of the elongated spermatid nuclei appreciably malformed. Leydig cells were atrophied but their number and the peritubular myoid cell number per testis were unchanged. Conclusion: Double inhibition of spermatogenesis (i.e. inhibition at spermiation and spermatogonial conversion to type B spermatogonia), a scenario seen in the monkey and human following gona-dotrophin withdrawal, was not sufficiently effective for a complete spermatogenic suppression in the rat after TU treatment, probably due to ineffective inhibition of the Leydig cell population and therefore the intra-testicular testosterone levels.

关键词： Leydig cells rat spermatogenesis spermatogenic cells stereology testis testosterone

Reversible effect of testosterone undecanoate injection on spermatogenesis in rats

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Asian Journal of Andrology 2000年第3期2卷 207-211页

作者： Xiao-HongWEN Wing-HaiWANG Jian-SunTONG ZHENG-WeiYANG Gui-YuanZHANG MorphometricResearchLaboratory NortltSichuanMedicalCollegeNanchong637007 JiangsuScientificandTechnologicalInstituteforFamilyPlonning Nanjing210029 DepartmentofEndocrinology NationalResearchInstituteforFamilyPlanningBeijing100081China

Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminif-erous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereologicalmethods as a measure of the spermatogenic efficiency. Results: Low dose (8 mg/kg) TU treatment virtually hadno effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and se-vere suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of therecovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well toler-ated by animals. Conclusion: TU injection reversibly suppresses spermatogenesis in rats.

关键词： spermatogenesis stereology testis testosterone undecanoate