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Biased activity of soluble guanylyl cyclase:the Janus face of thymoquinone

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Acta Pharmaceutica Sinica B 2017年第4期7卷 401-408页

作者： Charlotte Detremmerie paul m.Vanhoutte Susan Leung Department of Pharmacology and Pharmacy and State Key Laboratory for Pharmaceutical Biotechnology Li Ka Shing Faculty of Medicinethe University of Hong KongHong KongChina

The natural compound thymoquinone, extracted from Nigella sativa(black cumin), is widely used in humans for its anti-oxidative properties. Thymoquinone is known for its acute endotheliumindependent vasodilator effects in isolated rat aortae and pulmonary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium channels and inhibition of voltage-dependent calcium channels. The compound also improves endothelial dysfunction in mesenteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously,thymoquinone was found to augment contractions in isolated arteries with endothelium of both rats and pigs. The endothelium-dependent augmentation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase(sGC) producing inosine 3',5'-cyclic monophosphate(cyclic ImP) rather than guanosine 3',5'-cyclic monophosphate. This phenomenon shows a striking mechanistic similarity to the hypoxic augmentation previously observed in porcine coronary arteries. The cyclic ImP preferentially produced under thymoquinone exposure causes an increased contractility of arterial smooth muscle by interfering with calcium homeostasis. This brief review summarizes the vascular pharmacology of thymoquinone, focussing in particular on how the compound causes endothelium-dependent contractions by biasing the activity of sGC.

关键词： Thymoquinone Endothelium-dependentcontraction Nitric oxide Soluble guanylyl cyclase Cyclic ImP NADPH:quinone oxidoreductase

Anisotropy in dynamic recrystallization behavior of AZ31 magnesium alloy

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Journal of magnesium and Alloys 2022年第12期10卷 3470-3484页

作者： S.m.Fatemi S.Kheyrabadi H.paul Department of metallurgy and materials Engineering Shahid Rajaee Teacher Training University136-16785 TehranIran Institute of metallurgy and materials Science Polish Academy of Sciences(PAS)25 Reymonta Street30-059 KrakowPoland

Deformation behavior as well as microstructural evolutions of a rolled AZ31 magnesium alloy with and without pre-existing extension twins were studied using compression tests which performed along different orientations at a temperature range of 25–350 ℃. The results implied that the initial texture not only influence the evolution of flow stress, but also change the size and fraction of recrystallized *** contrast to samples parallel to rolling and transverse directions, compression along normal direction resulted in a respectful softening at 150 ℃. The largest size and fraction of new grains at 250 ℃ were recorded after deformation along rolling direction, while the maximum flow softening was observed during deformation along normal direction. The anisotropy in microstructural evolutions was still retained at 350 ℃. Pre-existing twins could reduce the anisotropy of material in respect of flow stress as well as DRX progression, where TD sample showed the lowest DRX fraction at 250 ℃. Quaternion misorientation data obtained from EBSD analysis of pretwinned material implied that initial texture could not significantly influence final texture. A different misorientation distribution was realized after deformation of pretwinned material along ND and RD directions.

关键词： Slip Recrystallization Grain size Growth Twin

The Jehol Biota (Lower Cretaceous, China): new discoveries and future prospects

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Integrative Zoology 2006年第1期1卷 15-17页

作者： paul m.BARRETT Jason m.HILTON Department of Palaeontology Natural History MuseumLondonUK School of Geography Earth and Environmental SciencesUniversity of BirminghamUK

Continuing work on the paleontology and sedimentology of the Jehol Group(Lower Cretaceous,China)is yielding numerous new insights into the evolution of many mesozoic plant and animal ***,many questions remain unanswered regarding Jehol paleoenvironments,paleobiology and *** of this information will be crucial in providing a detailed reconstruction of this extinct ecosystem.

关键词： climate Jehol Biota paleobotany paleozoology

Effects of Enriched Biochars Containing magnetic Iron Nanoparticles on mycorrhizal Colonisation,Plant Growth,Nutrient Uptake and Soil Quality Improvement

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Pedosphere 2015年第5期25卷 749-760页

作者： Stephen JOSEPH Hossain m.ANAWAR paul STORER paul BLACKWELL Chee CHIA Yun LIN paul mUNROE Scott DONNE Josip HORVAT Jianli WANG Zakaria m.SOLAImAN School of materials Science and Engineering University of New South WalesSydney Discipline of Chemistry University of Newcastle Institute for Superconducting and Electronic materials and School of Physics University of Wollongong Soil Biology and molecular Ecology Group School of Earth and Environment (M087) and UWA Institute of AgricultureFaculty of ScienceThe University of Western Australia Australian mineral Fertilisers Pty Ltd. Department of Agriculture and Food Western Australia Geraldton Regional Office Institute for Superconducting and Electronic materials University of Wollongong

At present, there is little commercial sale of biochar, since farmers find they can not gain a return on their investment in this amendment in the first few years after its application, because of the high cost associated with large application rates. To overcome this constraint, development of artificially aged enriched biochar-mineral complexes(BmCs), having a higher mineral content, surface functionality, exchangeable cations, high concentration of magnetic iron(Fe) nanoparticles, and higher water-extractable organic compounds has been undertaken by a combined team of researchers and a commercial company. Two biochars produced under different pyrolysis conditions were activated with a phosphoric acid treatment. A mixture of clay, chicken litter, and minerals were added to the biochar, and then this composite was torrefied at either 180 or 220?C. In this study a pot experiment was carried out in glasshouse conditions to determine the effects of four different BmCs, with different formulations applied at rates of 100 and 200 kg ha-1, on the mycorrhizal colonisation, wheat growth and nutrient uptake, and soil quality improvement. It was found that the phosphorus(P) and nitrogen uptake in wheat shoots were significantly greater for a low application rate of BmCs(100 kg ha-1). The present formulation of BmC was effective in enhancing growth of wheat at low application rate(100 kg ha-1). The increase in growth appeared due to an increase in P uptake in the plants that could be partly attributed to an increase in mycorrhizal colonisation and partly due to the properties of the BmC.

关键词： biochar-mineral complexes Fe nanoparticles P uptake redox reactions

A note on circle packing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第8期13卷 559-564页

作者： Young Joon AHN Christoph m. HOFFmANN paul ROSEN Department of mathematics Education Chosun University Gwangju 501-759 Korea Department of Computer Science Purdue University West Lafayette IN 47907 USA Scientific Computing and Imaging Institute University of Utah Salt Lake City UT 84112 USA

The problem of packing circles into a domain of prescribed topology is considered. The circles need not have equal radii. The Collins-Stephenson algorithm computes such a circle packing. This algorithm is parmlelized in two different ways and its performance is reported for a triangular, planar domain test case. The implementation uses the highly parallel graphics processing unit （GPU） on commodity hardware. The speedups so achieved are discussed based on a number of experiments.

关键词： Circle packing Algorithm performance Parallel computation Graphics processing unit (GPU)

Selenoprotein expression is regulated at multiple levels in prostate cells

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Cell Research 2006年第12期16卷 940-948页

作者： Cheryl m Rebsch Frank J Penna Ⅲ paul R Copeland Department of molecular Genetics Microbiology and immunology Department of molecular Genetics Microbiology and immunologyThe Cancer Institute of New JerseyUMDNJ-Robert Wood Johnson Medical School675 Hoes LanePiscatawayNJ 08854USA

Selenium supplementation in a population with low basal blood selenium levels has been reported to decrease theincidence of several cancers including prostate *** on the clinical findings,it is likely that the antioxidantfunction of one or more selenoproteins is responsible for the chemopreventive effect,although low molecular weightseleno-compounds have also been posited to selectively induce apoptosis in transformed *** address the effects ofselenium supplementation on selenoprotein expression in prostate cells,we have undertaken an analysis of antioxidantselenoprotein expression as well as selenium toxicity in non-tumorigenic prostate epithelial cells(RWPE-1)and prostatecancer cells(LNCaP and PC-3).Our results show that two of the glutathione peroxidase family members(GPX1 andGPX4)are highly induced by supplemental selenium in prostate cancer cells but only slightly induced in RWPE-1 *** addition,GPX1 levels are dramatically lower in PC-3 cells as compared to RWPE-1 or LNCaP ***2 proteinand mRNA,however,are only detectable in RWPE-1 *** the three selenium compounds tested(sodium selenite,sodium selenate and selenomethionine),only sodium selenite shows toxicity in a physiological range of *** and in contrast to previous studies,RWPE-1 cells were significantly more sensitive to selenitethan either of the prostate cancer cell *** results demonstrate that selenoproteins and selenium metabolism areregulated at multiple levels in prostate cells.

关键词： prostate selenium selenoproteins glutathione peroxidase selenocysteine

INTRINSIC FLUORESCENCE CHANGES IN NERVE TERmINALS,EVOKED BY ACTION POTENTIALS,ARE mODULATED BY KREBS CYCLE SUBSTRATES

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 209-214页

作者： paul KOSTERIN ANA LIA OBAID BRIAN m.SALZBERG Department of Neuroscience University of Pennsylvania School of medicine Philadelphia PA 19104USA Department of Physiology University of Pennsylvania School of medicine Philadelphia PA 19104USA

Electrical stimulation of the mammalian neurohypophysial infundibular stalk evokes the entry of Nat and Ca^(2+) into the neurosecretory terminals during the action *** events,in turn,increase intracellular Ca^(2+) and activate NaK-and Ca-ATPases,prompting the mitochondria to increase oxidative phosphorylation which can be monitored by recording the changes in FAD and *** paper reflects our efforts to determine whether or not modulating the capacity of mitochondria to produce ATP,by changing the concentrations of two important substrates of the Krebs cycle of the nerve terminal mitochondria,pyruvate and glucose,has an effect on the intrinsicfluorescence changes triggered by action potential stimulation.

关键词： Fluorescence FAD NADH action potential metabolism

Pressurized environments directly influence friction and wear of dry steel contacts—Investigations in a novel high fluid pressure tribometer

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Friction 2024年第7期12卷 1599-1617页

作者： paul REICHLE Jakob BARZ Georg UmLAUF Günter E.m.TOVAR Institute of Interfacial Process Engineering and Plasma Technology(IGVP) University of StuttgartStuttgart 70569Germany Fraunhofer Institute for Interfacial Engineering and Biotechnology(IGB) Stuttgart 70569Germany

To reduce the usage of classical lubricants in deep drawing,a new tribological system based on volatile lubricants was ***,a volatile medium is injected under high pressure into the interstice between drawing tool and sheet *** on temperature and pressure,the temporary lubricant may exist in its gaseous or liquid *** this study,a novel high fluid pressure tribometer was designed to investigate the friction and wear of dry steel contacts under comparable conditions like in dry deep ***,a new ball-on-disc tribometer was designed and integrated into a high-pressure *** specifically investigate the effects of different environments(technical air,liquid and gaseous carbon dioxide,nitrogen,argon)at atmospheric and high pressure(0.1 mPa,6 mPa)on tribology,the specimens and all components were operating *** the experiments,the friction was measured *** show that the highest friction occurs in air and the lowest in carbon dioxide *** to the experiments,the wear of the specimens was assessed along with changes in surface chemistry related to tribochemical ***,the tribology of the dry sliding contacts is correlated to changes of the surface *** differences as well as similarities regarding the different fluid environments are *** the results show,the differences between the media used are most pronounced at elevated ***,this work gives clear indications on the suitability of volatile lubricants in dry friction or rather gas lubrication,especially for dry deep drawing.

关键词： dry friction and dry wear gas lubrication carbon dioxide tribo-layer dry metal forming

Automated Deep Learning Based Cardiovascular Disease Diagnosis Using ECG Signals

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Computer Systems Science & Engineering 2022年第7期42卷 183-199页

作者： S.Karthik m.Santhosh m.S.Kavitha A.Christopher paul Department of Computer Science&Engineering SNS College of TechnologyCoimbatore641035India Department of Information Technology Karpagam Institute of TechnologyCoimbatore641105India

Automated biomedical signal processing becomes an essential process to determine the indicators of diseased *** the same time,latest develop-ments of artiﬁcial intelligence(AI)techniques have the ability to manage and ana-lyzing massive amounts of biomedical datasets results in clinical decisions and real time *** can be employed for medical imaging;however,the 1D biomedical signal recognition process is still needing to be ***(ECG)is one of the widely used 1-dimensional biomedical sig-nals,which is used to diagnose cardiovascular *** assisted diag-nostic modelsﬁnd it difﬁcult to automatically classify the 1D ECG signals owing to time-varying dynamics and diverse proﬁles of ECG *** resolve these issues,this study designs automated deep learning based 1D biomedical ECG sig-nal recognition for cardiovascular disease diagnosis(DLECG-CVD)*** DLECG-CVD model involves different stages of operations such as pre-proces-sing,feature extraction,hyperparameter tuning,and classiﬁ*** the initial stage,data pre-processing takes place to convert the ECG report to valuable data and transform it into a compatible format for further *** addition,deep belief network(DBN)model is applied to derive a set of feature ***,improved swallow swarm optimization(ISSO)algorithm is used for the hyper-parameter tuning of the DBN ***,extreme gradient boosting(XGBoost)classiﬁer is employed to allocate proper class labels to the test ECG *** order to verify the improved diagnostic performance of the DLECG-CVD model,a set of simulations is carried out on the benchmark PTB-XL dataset.A detailed comparative study highlighted the betterment of the DLECG-CVD model interms of accuracy,sensitivity,speciﬁcity,kappa,mathew correlation coefﬁcient,and Hamming loss.

关键词： Biomedical signals 1-dimensional signal electrocardiogram artiﬁcial intelligence deep learning cardiovascular disease decision making