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Probability to retrieve testicular spermatozoa in azoospermic patients

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Asian journal of Andrology 2000年第3期2卷 199-205页

作者： H.-j.glanden L.-C.Horn W.Dorschner u.Paasch j.Kratzsch Department of Dermatology/Andrology unit Department of Dermatology Department of PathologyDepartment of Dermatology Department of UrologyDepartment of Dermatology/Andrology UnitDepartment of Clinical Chemistry and Pathological Biochemistry University of Leipzig D-04103 Leipzig Germany

Aim: The degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection intooocytes is of interest for counselling of infertility patients. We investigated the relation of sperm retrieval to clinical dataand histological pattern in testicular biopsies from azoospermic patients. Methods: In 264 testicular biopsies from142 azoospermic patients, the testicular tissue was shredded to separate the spermatozoa, histological semi-thin sec-tions of which were then evaluated using johnsen score. Results: The retrieval of spermatozoa correlated signifi-cantly (P ular volume (r = 0.49), the FSH concentration ( r = -0.66), the maximum score(r = 0.85) and the mean johnsen score (r = 0.81). In the multivariate regression analysis the successful testicularsperm extraction showed the closest relationship to the maximum score. The testicular volume correlated significantlywith the mean johnsen score ( r = 0.64, P um FSH concentration mainly with the maxi-mum score ( r = -0.77; P gnificantly lower johnsenscore compared to the patients who did not have any testicular disease in the past (3.7 ± 2.4 vs. 5.9 ± 2. 5; P usion: In a limited range, the testicular volume and the FSH concentration in serum were related to thejohnsen score which correlated significantly with the sperm retrieval. The successful sperm retrieval can be expected inall azoospermic patients irrespective of the results of clinical examination. However, the probability of retrieval of sper-matozoa decreased significantly in patients with a FSH level > 18 u/L, tesficular volume johnsen scoreum johnsen score < 7.

关键词： sperm extraction testicular histology azoospermia male infertility follicle stimulating hormone

The Friction and Wear Properties of CrN, graphit-iC and Dymon-iC Coatings in Air and under Oil-lubrication.

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材料热处理学报 2004年第05B期25卷 858-861页

作者： j. Stallard D.g Teer Teer Coatings Ltd Droitwich WorcestershireU.KTeer Coatings Ltd Droitwich WorcestershireU.K.

Hard ceramic coatings such as TiN and CrN are very successful and are widely used in improving the performance of cutting and forming tools, but they are less successful in providing protection for general machine components, such as gears and engine parts. The development of low-friction wear resistant coatings that can run dry or in a minimum amount of oil is becoming increasingly important to this industry. Two recently developed carbon-based coatings graphit-iC? and Dymon-iC, which are shown to exhibit very high sliding wear resistance and low friction in dry conditions, are compared to a CrN coating under oil lubricated conditions. Long term pin-on-disc tests using a chrome steel counterface ball were carried out on coated HSS test samples. All the coatings performed well at very high applied contact pressures, exceeding 1.5 gPa, but the graphit-iC? and Dymon-iC coatings also exhibited the desirable characteristic of protecting the counterface material. Reasons for this behaviour are discussed.

关键词： DLC 润滑油摩擦性能磨损性能涂层

Resonance properties from a coupled channel meson exchange model

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Chinese Physics C 2009年第12期33卷 1273-1278页

作者： M. Dring C. Hanhart 黄飞 S. Krewald u.-g. Meiβner Institut fr Kernphysik and jlich Center for Hadron Physics Forschungszentrum Jlich D-52425 JlichGermany Institute for Advanced Simulation Forschungszentrum Jlich D-52425 JlichGermany Department of Physics and Astronomy University of Georgia Athens Georgia 30602 USA Helmholtz-Institut fr Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics Universitt Bonn Nuβallee 14-16 D-53115 Bonn Germany

In this talk, I present the results on the pole structure of pion-nucleon scattering in an analytic model based on meson exchange. The analytic properties of scattering amplitudes provide important information. Besides the cuts, the poles and zeros on the different Riemann sheets determine the global behavior of the amplitude on the physical axis. Pole positions and residues allow for a parameterization of resonances in a well-defined way, free of assumptions for the background and energy dependence of the resonance part. This is a necessary condition to relate resonance contributions in different reactions.

关键词： pion-nucleon scattering meson exchange model analytic structure of the scattering amplitude

Evaluation of genetic diversity in short duration cotton(gossypium hirsutum L.)

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journal of Cotton Research 2018年第4期1卷 12-17页

作者： AKTER T. ISLAM A.K.M.A. RASuL M.g. KuNDu S. KHALEQuZZAMAN AHMED j.u. Department of genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural University Cotton Development Board (CBD) Department of Crop Botany Bangabandhu Sheikh Mujibur Rahman Agricultural University

Background: Cotton(gossypium hirsutum L.) is an important fiber crop in Bangladesh. genetic diversity among the genotypes of a germplasm has a great importance for cotton breeding. An experiment was carried out at the experimental field of Cotton Research, Training and Seed Multiplication Farm, Sreepur, gazipur during the cropping season of 2015-2016 with 100 genotypes to evaluate genetic diversity of cotton genotypes for short duration using field ***: The genotypes under study were grouped into ten clusters through multivariate analysis using *** III contained maximum number of genotypes(16) while cluster X contained the least number of genotypes(7).The inter cluster distances were larger than intra cluster distances in all cases suggesting wider genetic diversity among the genotypes of different clusters. The maximum and minimum inter cluster distances were observed between clusters II and V(10.78) and clusters VIII and IX(3.30), respectively. The results indicated diverse and close relationship among the genotypes of those clusters. Earliness index, single boll weight and days to boll opening showed the higher contribution to the genetic divergence among 19 ***: Based on the results of genetic diversity and earliness index, the genotypes from cluster Ⅱ could be used as parent in hybridization program for the development of short duration cotton variety.

关键词： Cotton(gossypium hirsutum L.) genetic diverity Earliness index gOT Yield

Molecular dynamics of amorphous pharmaceutical fenofibrate studied by broadband dielectric spectroscopy

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journal of Pharmaceutical Analysis 2016年第3期6卷 165-170页

作者： u. Sailaja M. Shahin Thayyil N.S. Krishna Kumar g. govindaraj Department of Physics M.E.S Keveeyam College. Valanchery 676552 Malappuram Kerala India Department of Physics University of Calicut 673635 Kerala. India Department of Physics School of Physical Chemical and Applied Sciences Pondicherry University Puducherry 605014 India

Fenofibrate is mainly used to reduce cholesterol level in patients at risk of cardiovascular disease. Thermal transition study with the help of differential scanning calorimetry （DSC） shows that the aforesaid active pharmaceutical ingredient （API） is a good glass former. Based on our DSC study, the molecular dynamics of this API has been carried out by broadband dielectric spectroscopy （BDS） covering wide temperature and frequency ranges. Dielectric measurements of amorphous fenofibrate were per- formed after its vitrification by fast cooling from a few degrees above the melting point （Tm=354.11 K） to deep glassy state. The sample does not show any crystallization tendency during cooling and reaches the glassy state. The temperature dependence of the structural relaxation has been fitted by single Vogel- Fulcher-Tamman （VFT） equation. From VFT fit, glass transition temperature （Tg） was estimated as 250.56 K and fragility （m） was determined as 94.02. This drug is classified as a fragile glass former. Deviations of experimental data from Kohlrausch-Williams-Watts （KWW） fits on high-frequency flank of α-peak indicate the presence of an excess wing in fenofibrate. Based on Ngai＇s coupling model, we identified the excess wing as true johari-goldstein （jg） process. Below the glass transition temperature one can clearly see a secondary relaxation （γ） with an activation energy of 32.67 kj/mol.

关键词： Amorphous fenofibrate Bioavailability Broadband dielectric spectroscopy glass transition Molecular dynamics

Plasticity and Interfacial Dislocation Mechanisms in Epitaxial and Polycrystalline Al Films Constrained by Substrates

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journal of Materials Science & Technology 2002年第2期18卷 113-117页

作者： g.Dehm B.j.Inkson 等 Max-Planck-InstitutfirtMetallforschung Seestr9270174StuttgartGermany DepartmentofMaterials UniversityofOxfordParksRoadOxfordOX13PHU.K.

Stresses in epitaxial and textured Al films were determined by substrate-curvature measurements. It was found that in both cases the flow stresses increase with decreasing film thickness. The flow stresses in the epitaxial Al films are in agreement with a dislocation-based model, while the same model strongly underestimates the flow stresses of textured Al films. In-situ transmission electron microscopy studies indicate that dislocations channeling through epitaxial Al films on single-crystalline (0001) α-AI2O3 substrates frequently deposit dislocation segments adjacent to the interface. Furthermore, the AI/α-AI2O3 interface acted as a dislocation source. In this case, the interface is between two crystalline lattices. In contrast, the interface of textured Al films on oxidized silicon substrates is between the crystalline Al and the amorphous SiOx interlayer. It is speculated that the different nature of the interfaces changes dislocation mechanisms and thus influences the flow stresses.

关键词： Thin film Plasticity Dislocation Interface

Optical properties of electrochemically synthesized polypyrrole thin films:the electrolyte effect

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journal of Semiconductors 2014年第6期35卷 1-4页

作者： j.V.Thombare S.K.Shinde g.M.Lohar u.M.Chougale S.S.Dhasade H.D.Dhaygude B.P.Relekar V.j.Fulari Holography and Materials Research Laboratory Department of PhysicsShivaji University Department of Physics Vidnyan MahavidyalyaSangola

Polypyrrole thin films are prepared by the potentiostatic mode of electrodeposition at ＋0.7 V versus a saturated calomel electrode （SCE）. The polypyrrole films are prepared in the presence of different electrolytes such as： p-toluene sulphonic acid （PTS）, oxalic acid and H2SO4. The prepared films are characterized by uV- vis absorption spectroscopy and normal reflectance measurements. The electrochemically synthesized films are semiconductor in nature. The band gap energy ofpolypyrrole thin films is found to be 1.95, 1.92 and 1.79 eV for H2 SO4, oxalic acid and p-toluene sulphonic acid, respectively. The normal reflectance spectroscopy of polypyrrole films shows that the maximum reflectance is in the presence of p-toluene sulphonic acid; this is may be due to a more distinct microstructure than the others. The optical constants such as the extinction coefficient, refractive index, optical conductivity, etc. are calculated and studied with various electrolytes.

关键词： electrodeposition polypyrrole extinction coefficient refractive index

Hairless canary seeds (Phalaris canariensis L.) as a potential source of antioxidant, antihypertensive, antidiabetic, and antiobesity biopeptides

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Food Production, Processing and Nutrition 2021年第1期3卷 80-91页

作者： u.C.urbizo-Reyes j.E.Aguilar-Toalá A.M.Liceaga Protein Chemistry and Bioactive Peptides Laboratory Department of Food SciencePurdue University745 Agriculture Mall DriveWest LafayetteIN 47907USA

Rising consumer concerns with synthetic drugs to treat non-communicable diseases(NCDs)have promoted a shift towards using natural biological active constituents that offer similar health *** canary seed(Phalaris canariensis L)is an emerging crop traditionally used in Mexico to treat *** liberated during simulated digestion of canary seed protein are believed to be responsible for their biological activity;however,no studies have shown the effect of controlled protein hydrolysis using commercial proteases on canary seed protein’s biological ***,this study aimed to explore the in vitro antihypertensive,antidiabetic,and anti-obesity activity of canary seed peptides derived from proteolysis with Alcalase®.Protein fractions were primarily composed of prolamins(54.07±1.8%),glutelins(32.19±3.18%),globulins(5.97±0.52%)and albumins(5.97±0.52%).Theghest inhibition capacity(pgiotensin-converting enzyme(IC50=0.028–0.032 mg/mL)lipase(IC50=2.15–2.27 mg/mL),α-glucosidase(IC50=0.82–1.15 mg/mL),and dipeptidyl-peptidase-IV(IC50=1.27–1.60 mg/mL).Additionally,these peptide fractions showed high antioxidant activity against DPPH(134.22–150.66μmol TE/mg)and ABTS(520.92–813.33μmol TE/mg).These results provide an insight into the potential development of functional foods using commercial enzymatic hydrolysis of canary seed proteins for treating hypertension,type-2 diabetes,and obesity.

关键词： Canary seeds Bioactive peptides Anti-obesity activity Antihypertensive activity Antidiabetic activity

Improved prediction of clay soil expansion using machine learning algorithms and meta-heuristic dichotomous ensemble classifiers

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geoscience Frontiers 2022年第1期13卷 268-284页

作者： E.u.Eyo S.j.Abbey T.T.Lawrence F.K.Tetteh Department of geography and Environmental Management University of the West of EnglandBristolUnited Kingdom Research Centre for Fluid and Complex Systems Coventry UniversityCoventryUnited Kingdom Department of Civil Engineering University of BirminghamBirminghamUnited Kingdom

Soil swelling-related disaster is considered as one of the most devastating geo-hazards in modern ***,proper determination of a soil’s ability to expand is very vital for achieving a secure and safe ground for ***,this study has provided a novel and intelligent approach that enables an improved estimation of swelling by using kernelised machines(Bayesian linear regression(BLR)&bayes point machine(BPM)support vector machine(SVM)and deep-support vector machine(D-SVM));(multiple linear regressor(REg),logistic regressor(LR)and artificial neural network(ANN)),tree-based algorithms such as decision forest(RDF)&boosted trees(BDT).Also,and for the first time,meta-heuristic classifiers incorporating the techniques of voting(VE)and stacking(SE)were *** independent scenarios of explanatory features’combination that influence soil behaviour in swelling were *** results indicated BLR as possessing the highest amount of deviation from the predictor variable(the actual swell-strain).REg and BLR performed slightly better than ANN while the meta-heuristic learners(VE and SE)produced the best overall performance(greatest R2 value of 0.94 and RMSE of 0.06%exhibited by VE).CEC,plasticity index and moisture content were the features considered to have the highest level of *** binary classifiers(SVM,D-SVM and BPM)gave better accuracy(average accuracy and recall rate of 0.93 and 0.60)compared to ANN,LR and ***-driven diagnostic test indicated that the meta-heuristic models’best performance occurred when ML training was conducted using k-fold validation ***,it is recommended that the concepts developed herein be deployed during the preliminary phases of a geotechnical or geological site characterisation by using the best performing meta-heuristic models via their background coding resource.

关键词： Artificial neural networks Machine learning Clays Algorithm Soil swelling Soil plasticity