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Sperm DNA damage in men from infertile couples

Asian Journal of Andrology 2008年第5期10卷 786-790页

作者： juris Erenpreiss Saad Elzanaty Aleksander Giwercman Andrology Laboratory Riga Stradins University LV-1007 Riga Latvia Reproductive Medicine Centre Scanian Andrology Centre Malmo University Hospital Malmo SE 205 02 Sweden Department of General Surgery Urology Section Kristianstad Central Hospital Kristianstad SE 291 85 Sweden

Aim： To investigate the prevalence of high levels of sperm DNA damage among men from infertile couples with both normal and abnormal standard semen parameters. Methods： A total of 350 men from infertile couples were assessed. Standard semen analysis and sperm chromatin structure assay （SCSA） were carried out. Results： Ninety-seven men （28% of the whole study group） had a DNA fragmentation index （DFI）〉 20%, and 43 men （12%） had a DFI 〉 30%. In the group of men with abnormal semen parameters （n = 224）, 35% had a DFI 〉 20%, and 16% had a DFI 〉 30%, whereas these numbers were 15% and 5%, respectively, in the group of men with normal semen parameters （n = 126）. Men with low sperm motility and abnormal morphology had significantly higher odds ratios （ORs） for having a DFI 〉 20% （4.0 for motility and 1.9 for morphology） and DFI 〉 30% （6.2 for motility and 2.8 for morphology） compared with men with normal sperm motility and morphology. Conclusion： In almost one-third of unselected men from infertile couples, the DFI exceeded the level of 20% above which, according to previous studies, the in vivo fertility is reduced. A significant proportion of men with otherwise normal semen parameters also had high sperm DNA damage levels. Thus, the SCSA test could add to explaining causes of infertility in cases where semen analysis has not shown any deviation from the norm. We also recommend running the SCSA test to choose the appropriate assisted reproductive technique （ART）.

关键词： infertility sperm DNA damage sperm chromatin structure assay semen quality

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Novel Mycelium-Based Biocomposites (MBB) as Building Materials

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Journal of Renewable Materials 2020年第9期8卷 1067-1076页

作者： Zinta Zimele Ilze Irbe juris Grinins Oskars Bikovens Anrijs Verovkins Diana Bajare Riga Technical University RigaLV-1658Latvia Latvian State Institute of Wood Chemistry RigaLV-1006Latvia

Novel mycelium-based biocomposites(MBB)were obtained from local agricultural(hemp shives)and forestry(wood chips)by-products which were bounded together with natural growth of fungal *** a result,hemp mycocomposites(HMC)and wood mycocomposites(WMC)were ***,water absorption and biodegradation properties of MBB were *** were characterized also by ash content and elemental *** results of MBB were compared with the reference materials such as the commercial MBB material manufactured by Ecovative®Design(EV),hemp magnesium oxychloride concrete(HC)and cemented wood wool panel(CW),manufactured by CEWOOD®.The mechanical properties of HMC and WMC showed that the bending strength difference was about 30%,with a better result for *** strength was better for WMC by about 60%compared to that of *** mechanical strength of HMC and HC materials was equal;both materials contained hemp shives but differed by the binding *** absorption and volumetric swelling tests showed that HMC and WMC could be considered as potential *** content and elemental analysis showed that reference materials(CW,HC)contained significant amounts of inorganic compounds that decreased the biodegradation rate,compared to the case of HMC and WMC *** biodegradation results of HMC and WMC,after 12 weeks,revealed a mass loss(ML)above 70%,while in the case of EV,HC and CW,it was about 60%,17%and only 6%,*** were completely biodegradable.

关键词： Mycelium-based biocomposites(MBB) mechanical properties water absorption biodegradation

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Heteronuclear Efimov resonances in ultracold quantum gases

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National Science Review 2016年第2期3卷 174-188页

作者： juris Ulmanis Stephan Hfner Eva D.Kuhnle Matthias Weidemller physikalisches Institut Universitt Heidelberg Hefei National Laboratory for physical Sciences at the Microscale and Department of Modern physics and CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum PhysicsUniversity of Science and Technology of China

The Efimov scenario is a universal three-body effect addressing many areas of modern quantum *** plays an important role in the transition between few- and many-body physics and has enabled important breakthroughs in the understanding of the universal few-body *** review the basic concepts of the Efimov scenario with specific emphasis on the similarities and differences between homonuclear and heteronuclear *** the latter scenario,the existence of a second,independently tunable interaction parameter enables novel few-body phenomena that are universal and have no counterexamples in the homonuclear *** discuss recent experimental approaches using ultracold atomic gases with magnetically tunable interactions and elucidate the role of short-range interactions in the emergence of universal and non-universal behavior.

关键词： Efimov resonances few-body physics Feshbach resonances ultracold atoms resonant scattering

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Seismites resulting from high-frequency, high-magnitude earthquakes in Latvia caused by Late Glacial glacio-isostatic uplift

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Journal of palaeogeography 2016年第4期5卷 363-380页

作者： A.J. (Tom) van Loon Matgorzata pisarska-Jamrozy Maris Nartiss Maris Krievans juris Soms Geocom Consultants Valle del Portet 17 03726 Benitachell Spain Institute of Geology Adam Mickiewicz University Makow Polnych 16 61-606 Poznan Poland Faculty of Geography and Earth Sciences University of Latvia Rainis Blvd. 19 1576 Riga Latvia Department of Geography Daugavpils University Parades 1 LV 5401 Daugavpils Latvia

Geologically extremely rapid changes in attitude by glacial rebound of the Earth crust after retreat of the Scandinavian Ice Sheet at the end of the last Weichsetian glaciation influenced the patae- ogeography of northern Europe. The up（ift of the Earth crust apparently was not gradual, but shock-wise, as the uplift was accompanied by frequent, high-magnitude earthquakes. This can be deduced from strongly deformed layers which are interpreted as seismites. Such seismites have been described from several coun- tries around the Baltic Sea, including Sweden, Germany and poland. Now similarly deformed layers that must also be interpreted as seismites, have been discovered also in Latvia, a Baltic country that was covered by an ice sheet during the last glaciation. The seismites were found at two sites： Near Vatmiera in the NE part and near Rakuti in the SE part of the country. The seismites were found in sections of about 7 m and 4.5 m high, respectively, that consist mainly of glaciofluvial and gtaciotacustrine sands and silts. At the Vatmiera site, 7 seismites were found, and at the Rakuti site these were even 12 seismites. The two sections have not been dated precisely up tilt now, but lithological correlations and geomorpho- logical characteristics suggest that the sediments at the Vatmiera site cannot be older than 14.5 ka. Because the accumulation of the section did not take more than about 1000 years, the average recurrence time of the high-magnitude （M≥4.5-5.0） earthquakes must have been maximally only 100-150 years, possibly only 6-7 years. The sediments at Rakuti must also have formed within approx. 1000 years （17-16 ka）, implying a recurrence time of high-magnitude earthquakes of maximaUy once per 100-200 years.

关键词： Soft-sediment deformation structures (SSDS) Seismites Latvia Glacio-isostatic rebound,Earthquake recurrence time

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Influence of gastric inhibitory polypeptide on pentagastrinstimulated gastric acid secretion in patients with type 2 diabetes and healthy controls

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World Journal of Gastroenterology 2006年第12期12卷 1874-1880页

作者： juris J Meier Michael A Nauck Bartholomaeus Kask Jens J Hoist Carolyn F Deacon Wolfgang E Schmidt Baptist Gallwitz Department of Medicine I St. Josef-HospitalRuhr-University Bochum Germany Diabeteszentrum Bad Lauterberg Germany Department of Medical physiology The Panum Institute University of Copenhagen Denmark Department of Medicine IV Eberhard-Karls- University Ttibingen Germany

AIM： Gastric inhibitory polypeptide is secreted from intestinal K-cells in response to nutrient ingestion and acts as an incretin hormone in human physiology. While animal experiments suggested a role for GIp as an inhibitor of gastric secretion, the GIp effects on gastric acid output in humans are still controversial. METHODS： pentagastrin was administered at an infusion rate of 1 μg . kg^-1 . h^-1 over 300 min in 8 patients with type 2 diabetes （2 female, 6 male, 54± 10 years, BMI 30.5 ± 2.2 kg/m^2; no history of autonomic neuropathy） and 8 healthy subjects （2/6, 46 ± 6 years., 28.9 ± 5.3 kg/ m^2）. A hyperglycaemic clamp （140 mg/dl） was performed over 240 min. placebo, GIp at a physiological dose （1 pmol . kg^-1 . min^-1）, and GIp at a pharmacological dose （4 mol . kg^-1 . min^-1） were administered over 60 min each. Boluses of placebo, 20 pmol GIp/kg, and 80 pmol GIp/kg were injected intravenously at the beginning of each infusion period, respectively. Gastric volume, acid and chloride output were analysed in 15-min intervals. Capillary and venous blood samples were drawn for the determination of glucose and total GIp. Statistics were carried out by repeated-measures ANOVA and one-way ANOVA. RESULTS： plasma glucose concentrations during the hyperglycaemic clamp experiments were not different between patients with type 2 diabetes and controls. Steady-state GIp plasma levels were 61 ±8 and 79 ± 12 pmol/I during the low-dose and 327±35 and 327± 17 pmol/I during the high-dose infusion of GIp, in healthy control subjects and in patients with type 2 diabetes, respectively （p= 0.23 and p 0.99）. pentagastrin markedly increased gastric acid and chloride secretion （p〈 0.001）. There were no significant differences in the rates of gastric acid or chloride output between the experimental periods with placebo or any dose of GIp. The temporal patterns of gastric acid and chloride secretion were similar in patients with type 2 diabetes and healthy controls （p= 0.86 and p= 0.6

关键词： Gastric inhibitory polypeptide Gastric acid secretion Type 2 diabetes Hyperglycemic clamp pentagastrin-stimulated acid secretion

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Affective responses to supervised 10-week programs of resistance exercise in older adults

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Journal of Sport and Health Science 2020年第6期9卷 604-613页

作者： Darren L.Richardson Michael J.Duncan Alfonso Jimenez paul M.juris Neil D.Clarke Centre for Applied Biological&Exercise Sciences School of Life SciencesCoventry UniversityCoventry CV12DSUK Department of Kinesiology University of Massachusetts AmherstAmherstMA 01003USA

Background:Resistance exercise has numerous,well-documented benefits on the health and functional performance of older ***,little information exists on the affective responses to resistance exercise in this *** affective responses can predict continued exercise behavior,examining if and how they differ between resistance exercise intensities and frequencies in older adults may provide important data to improve resistance exercise ***:We monitored the affective responses of older adults when performing high-velocity,low-load(HVLL)or low-velocity,high-load(LVHL)resistance exercise once or twice weekly.A total of 40 moderately to highly active,but resistance-exercise naïve,older adults(60-79 years)completed 1 of 4 randomly assigned progressive resistance exercise conditions:HVLL once weekly(HVLL1:n=10),HVLL twice weekly(HVLL2:n=10),LVHL once weekly(LVHL1:n=10),or LVHL twice weekly(LVHL2:n=10).The physical Activity Affect Scale,Felt Arousal Scale,Feeling Scale,rating of perceived exertion,Visual Analog Scale,and the physical Activity Enjoyment Scale were used to assess enjoyment and affective ***:The results from physical Activity Enjoyment Scale(out of 35)suggest that all exercise conditions were largely and similarly enjoyable to older adults(HVLL1:30.9±2.4;LVHL1:31.9±3.6;HVLL2:30.9±3.5;LVHL2:30.2±3.7)despite greater fatigue(p=0.033;ηp^2p=0.22)and perceived workload(p=0.042;ηp^2=0.20)in LVHL(results from Visual Analog Scale).Conclusion:Moderately to highly physically active older adults may tolerate higher intensities of resistance exercise performed once or twice weekly without experiencing a negative impact on ***,the role that supervision and social interaction played in shaping the participants’responses is unclear.

关键词： Aging Enjoyment Exercise affect Health education Older adults

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关于计算复杂度及计算机科学的本质——93图灵奖演讲

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计算机科学 1995年第2期 1-5页

作者： juris Hartmanis 刘瑞挺宋战江南开大学计算机系南开大学计算机系

1993年度ACM图灵奖由juris Hartmanis与Richard Stearns分享,本文是前者的获奖讲演。文中讲到了获奖者的坎坷经历和不平凡的研究生涯,如何从图灵的早期论文和香农的通信理论中受到启发,探索出一个新的领域——计算复杂度理论,从而开辟... 详细信息

1993年度ACM图灵奖由juris Hartmanis与Richard Stearns分享,本文是前者的获奖讲演。文中讲到了获奖者的坎坷经历和不平凡的研究生涯,如何从图灵的早期论文和香农的通信理论中受到启发,探索出一个新的领域——计算复杂度理论,从而开辟了理论计算机科学的一个重要分支。讲演中对计算机科学的本质有精辟而独到的见解.他认为“大部分计算机科学的活动都可以看作是工程”,“是一种新型的工程”,“我们不应该企图把计算机科学与工程严格分开,任何想分离这二者的意图都不会有结果的”,“应当为我们的科学具有如此强的应用性而骄傲”。这些辩证观点无疑值得我们思考和借鉴。

关键词：计算机科学物理科学计算复杂度科学的本质

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Biodegradable polysaccharide Gels for Skin Scaffolds

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Journal of Biomaterials and Nanobiotechnology 2011年第3期2卷 216-225页

作者： Stephen juris Anja Mueller Brian Smith Samantha Johnston Robert Walker Robert Kross 不详

A variety of skin substitutes are used in the treatment of full-thickness burns. Substitutes made from skin can harbor latent viruses, and artificial skin grafts can heal with extensive scarring, failing to regenerate structures such as glands, nerves, and hair follicles. Biodegradable and biocompatible hydrogels, however, rarely mimic the strength of the epidermis. Therefore, novel and practical skin scaffold materials remain to be developed. polysaccharides form hydrogels with predicted inherent biocompatibility. This paper describes the preparation and biocompatibility of unique hydrogel skin scaffolds from plant-extracted polysaccharide mixtures of specific sources, types, and molecular weight fractions. These hydrogels have a range of mechanical and degradation properties with the potential to fulfill the multiple, diverse functions of artificial skin, including protection, compatibility with different cell types, biodegradation, and release of needed signals for cell growth and wound healing.

关键词： hydrogel polysaccharides skin scaffold

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Speciation of Volatile Selenium Species in plants Using Gas Chromatography/Inductively Coupled plasma Mass Spectrometry

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色谱 2004年第1期22卷 16-19页

作者： juris MEIJA Maria MONTES-BAYN Joseph A CARUSO Danika L LEDUC Norman TERRY Department of Chemistry University of CincinnatiDepartment of ChemistryUniversity of CincinnatiDepartment of ChemistryUniversity of CincinnatiDepartment of Plant and Microbial Biology University of California BerkeleyDepartment of Plant and Microbial Biology University of California Berkeley Cincinnati OH 45221-0172USACincinnati OH 45221-0172USACincinnati OH 45221-0172USABerkeley CA 94720-3102 USABerkeley CA 94720-3102 USA

Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICp-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the headspace of growing plants. In this work, the technique was used to evaluate the volatilization of selenium in wild-type and genetically-modified Brassica juncea seedlings. By converting toxic inorganic selenium in the soil to less toxic, volatile organic selenium, B. juncea might be useful in bioremediation of selenium contaminated soil.

关键词：植物挥发性硒化合物含量测定气相色谱法电感耦合等离子体质谱法

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performance Characterization of Bituminous Mixtures With Dolomite Sand Waste and BOF Steel Slag

Performance Characterization of Bituminous Mixtures With Dol...

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ISAp2012重载沥青路面和桥面铺装专题会议

作者： Viktors Haritonovs Martins Zaumanis Guntis Brencis juris Smirnovs Riga Technical University Faculty of Civil Engineeringthe Institute of Transportation

＜正＞The rapid growth of transport loads in Latvia determines the needto increase the asphalt carrying capacity on large *** limestone and sandstone that can be found in Latvia,lack the mechanical strength and for most of the large motorways the aggregates are imported from other countries causing increase of the costs and growth of emissions from *** the other hand,large amounts of steel slag（BOF） aggregates with good qualities are being produced in Latvia and gone to *** the recent decades,the

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