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Journal of Computer Science & Technology 2023年第1期38卷 80-86页

作者： kirk W.Cameron Computer Science Virginia TechWashington D.C.VA 24061U.S.A.

Amdahl’s Law painted a bleak picture for large-scale *** implication was that parallelism was limited and therefore so was potential *** Amdahl’s contribution was seminal and important,it drove others vested in parallel processing to define more clearly why large-scale systems are critical to our future and how they fundamentally provide opportunities for speedup beyond Amdahl’s *** the early 2000s,much like Amdahl,we predicted dire consequences for large-scale systems due to power *** our early work was often dismissed,the implications were clear to some:power would ultimately limit *** this retrospective,we discuss how power-performance measurement and modeling at scale led to contributions that have driven server and supercomputer design for more than a *** the influence of these techniques is now indisputable,we discuss their connections,limits and additional research directions necessary to continue the performance gains our industry is accustomed to.

关键词： Amdahl’s Law speedup power-aware computing power modeling performance modeling performance prediction power measurement

Can we grow sperm？ A translational perspective on the current animal and human spermatogenesis models

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Asian Journal of Andrology 2011年第5期13卷 677-682页

作者： kirk C Lo Trustin Domes Department of Surgery University of Toronto Toronto Ont. Canada Division of Urology Department of Surgery Mount Sinai Hospital Toronto Ont. Canada

There have been tremendous advances in both the diagnosis and treatment of male factor infertility; however, the mechanisms responsible to recreate spermatogenesis outside of the testicular environment continue to elude andrologists. Having the ability to ＇grow＇ human sperm would be a tremendous advance in reproductive biology with multiple possible clinical applications, such as a treatment option for men with testicular failure and azoospermia of multiple etiologies. To understand the complexities of human spermatogenesis in a research environment, model systems have been designed with the intent to replicate the testicular microenvironment. Currently, there are both in vivoand in vitro model systems. In vivo model systems involve the transplantation of either spermatogonial stem cells or testicular xenographs. In vitro model systems involve the use of pluripotent stem cells and complex coculturing and/or three-dimensional culturing techniques. This review discusses the basic methodologies, possible clinical applications, benefits and limitations of each model system. Although these model systems have greatly improved our understanding of human spermatogenesis, we unfortunately have not been successful in demonstrating complete human spermatogenesis outside of the testicle.

关键词： fertility preservation spermatogenesis models spermatogonial stem cells

Comparing the Open University Systems of China and India:Origins,Developments and Prospects

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Frontiers of Education in China 2015年第2期10卷 274-305页

作者： kirk PERRIS Research Center of Distance Education School of Educational TechnologyFaculty of EducationBeijing Normal UniversityBeijing 100875China

The national open universities of China and India are unique adaptations of the open university model that emanated from the *** institutions have expanded to become the largest universities in the world as measured by current enrollment of approximately four million *** article comparatively analyzes how these open universities have differentiated themselves from the open university model and from each other amidst similarities of outcome and differences of *** contexts,national governance of higher education,institutional administration,curriculum and international operations are the foci of *** article contributes to the literature on national and local forces that shape higher education systems and aims to spur collaborations between the institutions in question for mutual benefit.

关键词： open university indigenization Indian higher education Chinese higher education comparative education

Neonatal colon perforation due to anorectal malformations: Can it be avoided?

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World Journal of Gastroenterology 2013年第25期19卷 3915-3917页

作者： Wei-Dong Tong kirk A Ludwig Gastric and Colorectal Division Department of Surgery Daping Hospital Third Military Medical University Division of Colorectal Surgery Department of Surgery Medical College of Wisconsin

Anorectal malformations (ARM) are common anomalies in neonates. Diagnostic and therapeutic delays in the management of ARM may lead to colonic perforation, and even death. Physical examination of the perineum is often sufficient to diagnose ARM in neonates. Notwithstanding, delayed diagnosis of ARM has become increasingly familiar to surgeons, as evidenced by the number of recent publications on this topic in the literature. In this commentary, we discuss spontaneous colonic perforation due to delayed diagnosis of ARM in neonates, and highlight the importance of early diagnosis in assuring good outcomes with surgical management. At this point, a thorough examination of the perineum during the initial newborn assessment is mandatory, particularly in those patients presenting with abdominal signs or symptoms.

关键词： Anorectal malformation Imperforate anus Bowel perforation Colon

Economic appraisal of shale gas resources, an example from the Horn River shale gas play, Canada

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Petroleum Science 2015年第4期12卷 712-725页

作者： Zhuoheng Chen kirk G.Osadetz Xuansha Chen Geological Survey of Canada University of Calgary ZLR Valeon

Development of unconventional shale gas resources involves intensive capital investment accompa- nying large commercial production uncertainties. Eco- nomic appraisal, bringing together multidisciplinary project data and information and providing likely economic outcomes for various development scenarios, forms the core of business decision-making. This paper uses a dis- counted cash flow （DCF） model to evaluate the economic outcome of shale gas development in the Horn River Basin, northeastern British Columbia, Canada. Through numerical examples, this study demonstrates that the use of a single average decline curve for the whole shale gas play is the equivalent of the results from a random drilling process. Business decision based on a DCF model using a single decline curve could be vulnerable to drastic changes of shale gas productivity across the play region. A random drilling model takes those drastic changes in well estimated ultimate recovery （EUR） and decline rates into account in the economic appraisal, providing more information useful for business decisions. Assuming a natural gas well-head price of S4/MCF and using a 10 % discount rate, the results from this study suggest that a random drilling strategy （e.g., one that does not regard well EURs）, could lead to a negative net present value （NPV）; whereas a drilling sequence that gives priority to developing those wells with larger EURs earlier in the drilling history could result in a positive NPV with various payback time and internal rate of return （IRR）. Under a random drilling assumption, the breakeven price is S4.2/MCF with more than 10 years of payout time. In contrast, if the drilling order is strictly proportional to well EURs, the result is a much better economic outcome with a breakeven price below the assumed well-head price accompanied by a higher IRR.

关键词： Drilling order EUR Risk aversion - Shalepetroleum resource

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被囚禁的女孩

Effects of ghrelin on interdigestive contractions of the rat gastrointestinal tract

2017年

作者： (美)香农·柯克(Shannon kirk)

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World Journal of Gastroenterology 2008年第41期14卷 6299-6302页

作者： Hiroshi Taniguchi Hajime Ariga kirk Ludwig Toku Takahashi Department of Surgery Medical College of Wisconsin and Zablocki VA Medical Center MilwaukeeWisconsin

Ghrelin causes interdigestive contractions of the stom- ach in rats. However, it remains unknown whether ghrelin causes interdigestive contractions in the small intestine. Four strain gauge transducers were implanted on the antrum, duodenum, proximal and distal jejunum. After an overnight fast, gastrointestinal （GI） contrac- tions were recorded in freely moving conscious rats. Spontaneous phase m-like contractions were observed at every 13-16 min in rat GI tract. The fasted motor patterns were replaced by the fed motor pattern imme- diately after food intake. Two minutes after finishing the spontaneous phase Ill-like contractions in the antrum, acyl ghrelin （0.8, 2.4 and 8.0 μg/kg per min） was con- tinuously infused for 30 min. Three-five minutes after the starting ghrelin infusion, augmented phase Ⅲ-like contractions were observed at the antrum, duodenum, and jejunum. Ghrelin infusion （0.8, 2.4 and 8.0μg/kg per min） significantly increased motility index of phase Ⅲ-like contractions at the antrum and jejunum in a dose dependent manner, compared to that of saline in- jection. Thus, it is likely that exogenously administered ghrelin causes phase Ⅲ-like contraction at the antrum, which migrates to the duodenum and jejunum. The possible role of 5-HT, in addition to ghrelin, in mediating intestinal migrating motor complex （MMC）, is discussed.

关键词： Phase Ⅲ-like contractions Strain gage transducers Motility index

Enhanced enzymatic removal of anthracene by the mangrove soil-derived fungus,Aspergillus sydowii BPOI

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 223-235页

作者： Paul Olusegun Bankole kirk Taylor Semple Byong-Hun Jeon Sanjay Prabhu Govindwar Department of Pure and Applied Botany College of BiosciencesFederal University of Agriculture AbeokutaOgun State 234039Nigeria Lancaster Environment Centre Lancaster UniversityLancaster LAI 4YQUK Department of Earth Resources and Environmental Engineering Hanyang UniversitySeoul 04763Republic of Korea

The present study investigated the efficiency of Aspergillus sydowii strain bpol(GenBank Accession Number:MK373021)in the removal of anthracene(100 mg/L).Optimal degradation efficiency(98.7%)was observed at neutral pH,temperature(30℃),biomass weight(2 g)and salinity(0.2%w/v)within 72 *** enzyme analyses revealed 131%,107%,and 89%induction in laccase,lignin peroxidase,and manganese peroxidase respectively during anthracene ***,the degradation efficiency(99.8%)and enzyme induction were significantly enhanced with the addition of 100 mg/L of citric acid and glucose to the *** varying anthracene concentrations(100-500 mg/L),the degradation rate constants(K1)peaked with increasing concentration of anthracene while the half-life(t1/2)decreases with increase in anthracene *** of fit(R2=0.976 and 0.982)was observed when the experimental data were subjected to Langmuir and Temkin models respectively which affirmed the monolayer and heterogeneous nature exhibited by *** cells during *** distinct metabolites;anthracene-1,8,9(2H,8aH,9aH)-trione,2,4adihydronaphthalene-1,5-dione,l,3,3a,7a-tetrahydro-2-benzofuran-4,7-dione and 2-hydroxybenzoic acid was obtained through Gas Chromatography-Mass spectrometry(GC-MS).*** exhibited promising potentials in the removal of PAHs.

关键词： Aspergillus sydowii Anthracene Biodegradation Polycyclic aromatic hydrocarbons

Seminal biomarkers for the evaluation of male infertility

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Asian Journal of Andrology 2016年第3期18卷 426-433,I0009页

作者： Jared M Bieniek Andrei P Drabovich kirk C Lo Department of Urology Hartford Hospital Hartford CT USA Department of Clinical Biochemistry University Health Network Toronto ON Canada Department ofLaboratory Medicine and Pathobiology University of Toronto Toronto ON Canada Department of Surgery Division of Urology Mount Sinai Hospital Toronto ONCanada.

For men struggling to conceive with their partners, diagnostic tools are limited and often consist of only a standard semen analysis. This baseline test serves as a crude estimation of male fertility, leaving patients and clinicians in need of additional diagnostic biomarkers. Seminal fluid contains the highest concentration of molecules from the male reproductive glands, therefore, this review focuses on current and novel seminal biomarkers in certain male infertility scenarios, including natural fertility, differentiating azoospermia etiologies, and predicting assisted reproductive technique success. Currently available tests include antisperm antibody assays, DNA fragmentation index, sperm fluorescence in situ hybridization, and other historical sperm functional tests. The poor diagnostic ability of current assays has led to continued efforts to find more predictive biomarkers. Emerging research in the fields of genomics, epigenetics, proteomics, transcriptomics, and metabolomics holds promise for the development of novel male infertility biomarkers. Seminal protein-based assays of TEXI01, ECM 1, and ACRV1 are already available or under final development for clinical use. Additional panels of DNA, RNA, proteins, or metabolites are being explored as we attempt to understand the pathophysiologic processes of male infertility. Future ventures will need to continue data integration and validation for the development of clinically useful infertility biomarkers to aid in male infertility diagnosis, treatment, and counseling.

关键词： assisted reproductive techniques diagnosis male infertility, semen

Effects of helium on irradiation-induced phase instability in a NiCrFeTiNbAl alloy

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Tungsten 2021年第1期3卷 58-64页

作者： He Zhang Zhong-Wen Yao Marquis A.kirk Department of Mechanical and Materials Engineering Queen’s UniversityKingston K7L 3N6Canada Material Science Division Argonne National LaboratoryArgonneIL 60439USA

The Ni–Fe–Cr based superalloy with percentage additions of Nb,Al and Ti,called"Inconel X750 superalloy",is studied with its importance in nuclear *** reactor neutron irradiation,the strengthening phase Ni3(Al,Ti)in the form of gamma prime precipitates were somehow disordered,and dissolved eventually,by which the mechanical properties of materials were *** is of high interests to investigate the e ects of transmutation production helium on radiationinduced instability of gamma prime in the *** transmission electron microscope in situ heavy ion irradiations with and without pre-injected helium are performed *** precipitates were disordered by heavy ion irradiation after 0.06 displacement per atom(dpa).The presence of 2×10-4 atoms helium delayed the disordering of Ni3(Al,Ti)precipitates to 0.68 *** 4×10-4 atoms helium,the precipitates required doses of>2.7 dpa to become *** addition,the precipitation of M23C6 particles were observed at 600℃irradiation to 5.4 dpa with 4×10-4 atoms helium pre-injected.

关键词： γ’Precipitates Disordering Inconel X-750 Helium pre-injection