检索结果-南通市图书馆

Neural Regeneration Research 2020年第8期15卷 1546-1553页

作者： Courtney j.Mycroft-West Anthony j.Devlin Lynsay C.Cooper Patricia Procter Gavin j.Miller David G.Fernig Marco Guerrini Scott E.Guimond Marcelo A.Lima Edwin A.Yates mark Andrew Skidmore Molecular&Structural Biosciences School of Life SciencesKeele UniversityHuxley BuildingKeeleStaffordshireST55BGUK Lennard-j.nes Laboratory School of Chemical and Physical SciencesKeele UniversityKeeleStaffordshireST55BGUK Department of Biochemistry Institute of Integrative BiologyUniversity of LiverpoolCrown StreetLiverpoolL697ZBUK Istituto di Ricerche Chimiche e Biochimiche G.Ronzoni Via G.Colombo 8120133 MilanItaly School of Medicine KeeleStaffordshireST55BGUK

The pharmaceutical and anticoagulant agent heparin,a member of the glycosaminoglycan family of carbohydrates,has previously been identified as a potent inhibitor of a key Alzheimer’s disease drug target,the primary neuronalβ-secretase,β-site amyloid precursor protein cleaving enzyme 1(BACE1).The anticoagulant activity of heparin has,however,precluded the repurposing of this widely used pharmaceutical as an Alzheimer’s disease ***,a glycosaminoglycan extract,composed predominantly of 4-sulfated chondroitin sulfate,has been isolated from Sardina pilchardus,which possess the ability to inhibit BACE1(IC50[half maximal inhibitory concentration]=4.8μg/mL),while displaying highly attenuated anticoagulant activities(activated partial thromboplastin time EC50[median effective concentration]=403.8μg/mL,prothrombin time EC50=1.3 mg/mL).The marine-derived,chondroitin sulfate extract destabilizes BACE1,determined via differential scanning fluorimetry(ΔTm–5°C),to a similar extent as heparin,suggesting that BACE1 inhibition by glycosaminoglycans may occur through a common mode of action,which may assist in the screening of glycan-based BACE1 inhibitors for Alzheimer’s disease.

关键词： amyloid-β aspartyl protease carbohydrates galactosaminoglycans heparan sulfate heparin marine polysaccharide pilchards sardines therapeutics

Avulsion Dynamics in a River with Alternating Bedrock and Alluvial Reaches, Huron River, Northern Ohio (USA)

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Open j.urnal of Modern Hydrology 2019年第1期9卷 20-39页

作者： mark j. Potucek j.mes E. Evans Arizona Department of Water Resources Phoenix AZ USA Department of Geology Bowling Green State University Bowling Green OH USA

The Huron River consists of alternating bedrock reaches and alluvial reaches. Analysis of historical aerial photography from 1950-2015 reveals six maj.r channel avulsion events in the 8-km study area. These avulsions occurred in the alluvial reaches but were strongly influenced by the properties of the upstream bedrock reach (“inherited characteristics”). The bedrock reaches aligned with the azimuth of j.int sets in the underlying bedrock. One inherited characteristic in the alluvial reach downstream is that the avulsion channels diverged only slightly from the orientation of the upstream bedrock channel (range 2 °- 38 °, mean and standard deviation 12.1 °± 13.7 °). A second inherited characteristic is that avulsion channels were initiated from short distances downstream after exiting the upstream bedrock channel reach (range 62 - 266 m, mean and standard deviation 143.7 ± 71.0 m), which is a fraction of the meander wavelength (1.2 km). Field evidence shows that some avulsion channel sites were re-occupied episodically. In addition, two properties were necessary for channel avulsions: 1) avulsion events were triggered by channel-forming hydrologic events (5-year recurrence interval flows), but not every channel-forming hydrologic event resulted in an avulsion, and 2) channel sinuosity (P) increased to 1.72 - 1.77 prior to an avulsion then decreased to 1.65 - 1.70 following an avulsion, suggesting that P ≥ 1.72 is the “critical sinuosity” or triggering value for avulsions on the Huron River. In summary, for this river consisting of alternating bedrock and alluvial reaches, the bedrock reaches impose certain parameters on downstream alluvial reaches (including sediment supply, channel direction and avulsion channel position downstream after exiting a bedrock reach) while adj.stments in sinuosity and sediment storage occur in the alluvial reaches.

关键词： Avulsion Bedrock Channels Alluvial Channels Cut-Offs Historical Changes Fluvial Sediment Budgets

MCSE:网络基础 14 天自学教程 1版

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Male fertility following childhood cancer: current conceptsand future therapies

1998年

作者： (美)mark Sportack Walter j. Glenn

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Asian j.urnal of Andrology 2003年第4期5卷 325-337页

作者： mark F. H. Brougham Christopher j. H.Kelnar Richard M.Sharpe W.Hamish B.Wallace Royal Hospital for Sick Children Edinburgh United KingdomRoyal Hospital for Sick Children Edinburgh United KingdomMRC Human Reproductive Sciences Unit Centre for Reproductive Biology University of Edinburgh United KingdomRoyal Hospital for Sick Children Edinburgh United Kingdom

Prepubertal boys treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeu tic agents have been identified as being gonadotoxic, and certain treatment regimens, such as that used for Hodgkin's disease, are particularly associated with subsequent infertility. Radiotherapy may also cause gonadal damage, most notably following direct testicular irradiation or total body irradiation. Because of the varied nature of the cytotoxic insult, it can be difficult to predict the likelihood of infertility in later life. Currently it is not possible to detect gonadal damage early due to the lack of a sensitive marker of gonadal function in the prepubertal age *** cryopreservation is currently the only method of preserving fertility in patients receiving gonadotoxic therapy. This is only applicable to postpubertal patients and can be problematic in the adolescent age group. At present there is no provision for the prepubertal boy, although there are a number of experimental methods currently being investigated. By harvesting testicular tissue prior to gonadotoxic therapy, restoration of fertility could be achieved following treatment, either by germ cell transplantation or by in vitro maturation of the germ cells harvested. Alternatively, rendering the testes quiescent during cytotoxic treatment may protect the germ cells from subsequent damage. In addition to the many scientific and technical issues to be overcome prior to clinical application of these techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.

关键词： infertility childhood cancer semen cryopreservation germ cell transplantation In vitro germ cell maturation assisted reproductive techniques

Fluidization and bubbling behavior of potash particles in a deep fluidized bed

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Particuology 2023年第9期80卷 103-114页

作者： Moj.aba Nabipoor Hassankiadeh j.ngsi Yang mark Berrey Dave j.rdison Lifeng Zhang Donald Bergstrom Raymond j.Spiteri Department of Chemical and Biological Engineering University of SaskatchewanSKS7N 5A9SaskatoonCanada The Mosaic Company Belle PlaineSKCanada Department of Mechanical Engineering University of SaskatchewanSaskatoonCanada Department of Computer Science University of SaskatchewanSaskatoonSKCanada

Most existing models for predicting bubble size and bubble frequency have been developed for freely bubbling fluidized *** prediction of bubbling behavior in deep fluidized beds,however,has been a challenge due to the higher degree of bubble coalescence and break up,high probability of the slugging regime,partial fluidization,and chaotic behavior in the bubbling *** this work,the bubbling and fluidization behavior of potash particles was investigated in a deep fluidized bed employing a twin-plane electrical capacitance tomography(ECT)*** volume fraction,average bubble velocity,average bubble diameter,and bubble frequency in both bubbling and slugging regimes were measured at two different bed height ratios(H/D=3.5 and H/D=3.78).This work is the first to illustrate a sequential view of bubbles at different superficial gas velocities in a fluidized *** results show that both the bubble diameter and rising velocity increased with increasing the superficial gas velocity for the two bed heights,with larger values observed in the deeper bed compared to the shallower *** values for bubble diameter,bubble rise velocity and bubble frequency from different models are compared with the experimental data obtained from the ECT system in this *** agreement has been achieved between the values predicted by the previous models and the experimental data for the bubble diameter and bubble rise velocity with an average absolute deviation of 16%and 15%for the bed height of 49 cm and 13%and 8%for the bed height of 53 cm,respectively.

关键词： Deep fluidized bed Potash particle Electrical capacitance tomography Image reconstruction Bubbling and slugging regime

Lead Free Finishes for Semiconductor and Connectors An Overview of Schloetter's Lead Free Programme August 2003

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Lead Free Finishes for Semiconductor and Connectors An Overv...

Length–mass allometries in amphibians

2003年全国电子电镀学术研讨会

作者： F.j.simmons Far East Export Manager Schloetter Co Ltd

Lead- Free Finishes for Semiconductor and Connectors Lead free finishes for electronic components will become the requirement by 2006 under the EU Directive. When the directive was initiated during 1999 the first companies to carry out trials using lead free electrolytes were the semiconductor *** processes available at that time were pure tin,tin bismuth

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Integrative Zoology 2018年第1期13卷 36-45页

作者： Luca SANTINI Ana BENÍTEZ-LÓPEZ Gentile Francesco FICETOLA mark A.j.HUIj.REGTS Department of Environmental Science Institute for Wetland and Water ResearchFaculty of ScienceRadboud UniversityNijmegenthe Netherlands Department of Bioscience University of MilanMilanItaly Alpine Ecology Laboratory Grenoble Alpes UniversityGrenobleFrance PBL Netherlands Environmental Assessment Agency The Haguethe Netherlands

Body mass is rarely recorded in amphibians,and other body measurements(*** to vent length,SVL)are generally collected ***,length measurements,when used as proxies of body mass in comparative analyses,are problematic if different taxa and morphotypes are *** developed allometric relationships to derive body mass from SVL *** fitted phylogenetic generalized least square models for frogs(Anura)and salamanders(Caudata)and for several families *** tested whether allometric relationships differed between species with different habitat preferences and between morphs in *** were fitted with SVL-mass measurements for 88 frog and 42 salamander *** assessed the predictive performance of the models by ***,the models showed high explained variance and low forecasting *** differed among semi-aquatic,terrestrial and arboreal frogs,and between paedomorphic and non-paedomorphic *** mass estimates derived from our models allow for comparability of studies on multiple taxa and can be used for testing theories built upon evolutionary and ecological processes which are directly related to body mass.

关键词： Anura body size body weight Caudata SVL

High-precision transfer-printing and integration of vertically oriented semiconductor arrays for flexible device fabrication

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2014年第7期7卷 998-1006页

作者： mark Triplett Hideki Nishimura Matthew Ombaba V. j. Logeeswarren Matthew Yee Kazim G. Polat j.n Y. Oh Takashi Fuyuki Francois Leonard M. Saif Islam Center for Nano and Micro Manufacturing and Department of Electrical and Computer Engineering University of California Davis CA 95616 USA Department of Physics University of California Davis CA 95515 USA Sandia National Laboratories Livermore CA 94551 USA Microelectronic Device Science Laboratory Nara Institute of Science and Technology Japan

Flexible electronics utilizing single crystalline semiconductors typically require post-growth processes to assemble and incorporate the crystalline materials onto flexible substrates. Here we present a high-precision transfer-printing method for vertical arrays of single crystalline semiconductor materials with widely varying aspect ratios and densities enabling the assembly of arrays on flexible substrates in a vertical fashion. Complementary fabrication processes for integrating transferred arrays into flexible devices are also presented and characterized. Robust contacts to transferred silicon wire arrays are demonstrated and shown to be stable under flexing stress down to bending radii of 20 mm. The fabricated devices exhibit a reversible tactile response enabling silicon based, nonpiezoelectric, and flexible tactile sensors. The presented system leads the way towards high-throughput, manufacturable, and scalable fabrication of flexible devices.

关键词： transfer printing nanowires flexible electronics printable electronics nanoscale devices

The availability of probiotics and donor human milk is associated with improved survival in very preterm infants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World j.urnal of Pediatrics 2018年第5期14卷 492-497页

作者： j.net Sharpe Mandy Way Pieter j.Koorts mark W.Davies Grantley Stable Neonatal Unit Department of NeonatologyRoyal Brisbane and Women’s HospitalButterfi eld StHerstonBrisbaneQLD 4029Australia Queensland Institute of Medical Research and Royal Brisbane and W omen’s Hospital Statistical Unit BrisbaneQLDAustralia Department of P ediatrics and Child Health The University of QueenslandBrisbaneQLDAustralia

Background To determine whether the introduction of pasteurized donor human milk and probiotics for infants born<32 weeks gestational age or<1500 g birthweight is associated with a reduction in mortality and the incidence of necrotising enterocolitis (NEC) and sepsis. Methods We performed a retrospective analysis of two cohorts: before and after the introduction of probiotics and pasteurised donor human milk. Univariate analysis of primary and secondary outcomes was performed;variables impacting outcomes were assessed using multivariate logistic regression. Results There were 1791 infants: 1334 in the pre-donor milk/probiotic cohort and 457 in the post-donor milk/probiotic cohort. On univariate analysis, mortality (7.6 vs. 2.4%, P<0.001) and incidence of sepsis (6.2 vs. 3.5%, P=0.028) were statistically significantly lower in the post-donor milk/probiotic group. NEC (2.8 vs. 1.5%, P=0.14) and non-NEC associ-ated gastrointestinal perforation (1.6 vs. 0.4%, P=0.052) were lower in the post-donor milk/probiotics cohort, but these were not statistically significant. The difference in mortality remained statistically significant on multivariate analysis in the post-donor milk/probiotic cohort compared to those in the pre-donor milk/probiotic cohort (odds ratio 0.31, 95% confidence interval 0.16–0.61). The decrease in the incidence of NEC was consistent with previous observational studies but the differ-ence was not statistically significant. Conclusion The availability of probiotics and pasteurised donor human milk is associated with a reduction in mortality in very preterm infants.

关键词： Enterocolitis necrotizing Infant newborn Milk human Milk banks Probiotics