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Chinese Journal of Chemistry 2004年第6期22卷 568-572页

作者：钱延龙 BALA Muhammad d. 谢小敏黄吉玲 Laboratory of Organometallic Chemistry East China University of Science and Technology Shanghai 200237 China

Yan-LongBALA, Muhammad d. XIE, Xiao-Min(HUANg, Ji-Ling*Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China Benzyl-substituted cyclopentadienyl lanthanide complexes were synthesized and characterized by elemental analysis, MS and IR spectroscopy. The analytical data point out the formation of monomeric, unsolvated complexes. In conjunction with Al(Et)3 as co-catalyst, the title complexes are efficient catalysts for the syndiotactic polymeriza-tion of methyl methacrylate. For the complex (C6H5CH2C5H4)2YCl, under the optimum polymerization conditions (60 ℃, n(MMA)∶n(catalyst)∶n(co-catalyst)=1000∶1∶10), a predominantly syndiotactic (rr=66%) polymer of high molecular weight (Mh=105000) was obtained.

关键词： benzyl-cyclopentadiene organolanthanide complex methyl methacrylate syndiotacticity polym-erization

基于FPgA的比特并行dWdM光动态包交换系统

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光电子．激光 2005年第10期16卷 1219-1222页

作者：唐闻新别荣芳林涛 Williams K.A. James L.B. Robert g.F. glick M. McAuley d. Engineering department Cambridge UniversityCambridge CB2 1PZUK 北京师范大学信息科学与技术学院北京100875 Intel Research Cambridge CB3 OFDUK

设计了一种全新的光路由器。采用单独的100 Mb/s的低速控制通道用来交换承载于波带(比特并行机制)带宽速率为80 gb/s的包,这种基于现场可编程门阵列(FPgA)实现的机制使得宽带交换可以应用在具备低时延、低成本特点的本地网(LAN)中,商用... 详细信息

设计了一种全新的光路由器。采用单独的100 Mb/s的低速控制通道用来交换承载于波带(比特并行机制)带宽速率为80 gb/s的包,这种基于现场可编程门阵列(FPgA)实现的机制使得宽带交换可以应用在具备低时延、低成本特点的本地网(LAN)中,商用化的FPgA用于驱动带宽的Mach-Zehnder干涉仪(MZI)和半导体光放大器(SOA)交换机。详细描述了为控制通道和数据通道设计的2种不同的时钟数据恢复模块(CdR)系统及其相关测试分析。对控制通道所有8个通道进行测试表明,在需要路由选址的情况下,测试结果稳定,且没有误码,和噪音层面出现。对于1 552.6 nm数据通道进行的背靠背和需要路由选址情况下,通过对MZI光交叉和SOA光交叉测量,得到额外的因为路由操作而导致的2.3 dB功率代价。

关键词：光包/突发交换(OPS/OBS) 比特并行dWdM 可编程门阵列(FPgA)的控制通道

Influence of dietary feathers on the fecal microbiota in captive Arctic fox:do dietary hair or feathers play a role in the evolution of carnivorous mammals?

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Integrative Zoology 2014年第5期9卷 583-589页

作者： Liang ZHANg Shuhui YANg Yanchun XU Thomas d.dAHMER College of Wildlife Resources Northeast Forestry UniversityHarbinHeilongjiangChina State Forestry Administration detecting Center of Wildlife HarbinChina Ecosystems Ltd. AberdeenHong KongChina

Hair and feathers are composed of keratin and are indigestible, inalimental and unpalatable for carnivores. However, carnivores often ingest hair and feathers during feeding or when grooming. We hypothesized that ingestion of hair and feathers changes species diversity and relative abundance of bacteria in the gut of carnivores. To test this hypothesis, we added disinfected poultry down feathers to the normal diet of captive Arctic foxes (Alopex lagopus). We then used fluorescently labeled terminal restriction fragments (T-RFs) to examine changes in fecal bacterial diversity and abundance. The results showed that the number of bacterial species increased significantly after feather ingestion, but that total abundance was unchanged. This demonstrated that addition of disinfected feathers to the diet stimulated increased production among less abundant bacteria, resulting in a balancing of relative abundance of different bacterial species, or that some newly-ingested microbial species would colonize the gut because a suitable microhabitat had become available. This implies that the overall production of bacterial metabolites would be made up of a greater range of substances after feather ingestion. On one hand, the host’s immune response would be more diverse, increasing the capacity of the immune system to regulate gut microflora. On the other hand, the animal’s physiological performance would also be affected. For wild animals, such altered physiological traits would be subjected to natural selection, and, hence, persistent geographic differences in the character of ingested feathers or fur would drive speciation.

关键词： carnivore diet evolution feather gut microbiota

An evidenced-based diagnostic tool for superior semicircular canal dehiscence syndrome

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Journal of Otology 2023年第4期18卷 230-234页

作者： Christian g.Fritz garrett g.Casale Lulia A.Kana Robert S.Hong Michigan Ear Institute Farmington HillsMichiganUSA department of OtorhinolaryngologyeHead&Neck Surgery University of PennsylvaniaPhiladelphiaPAUSA department of OtolaryngologyeHead and Neck Surgery Wayne State UniversityDetroitMIUSA

Purpose:To construct a symptoms-based prediction tool to assess the likelihood of superior canal dehiscence(SSCd)on high-resolution *** and methods:Mathematical modeling was employed to predict radiologic evidence of SSCd at a tertiary neurotology referral ***:A total of 168 patients were included,of which 118 had imaging-confirmed *** univariate analysis significant predictors of SSCd presence were:sound/pressure-induced vertigo(p?0.006),disequilibrium(p?0.008),hyperacusis(p?0.008),and autophony(p?0.034).Multivariate analysis enabled a 14-point symptom-weighted tool to be developed,wherein a score of6 raised the suspicion of SSCd(70%likelihood of being present),R2?***:The likelihood of SSCd on CT scan can be determined with a high degree of certainty based on symptoms recorded at *** the evidenced-based diagnostic tool validated herein,a score6 with any symptom combination justifies ordering a CT scan.

关键词： Clinical predictors diagnostic tool SSCd Superior semicircular canal dehiscence Third window

Sustained virologic response following HCV eradication in two brothers with X-linked agammaglobulinaemia

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World Journal of gastroenterology 2009年第31期15卷 3944-3946页

作者： diarmaid d Houlihan Eoin R Storan John M Lee department of gastroenterology University College Hospital Galway

X-linked agammaglobulinaemia (XLA) is a humoral immunodeficiency syndrome characterized from childhood by the absence of circulating B lymphocytes, absent or reduced levels of serum immunoglobulin and recurrent bacterial infections. For many affected patients, regular treatment with immunoglobulin is life saving. Hepatitis C viral (HCV) infection acquired through contaminated blood products is widely described in this patient cohort. The natural history of HCV infection in patients with XLA tends to follow a more rapid and aggressive course compared to immunocompetent individuals. Furthermore, standard anti-viral therapy appears to be less efficacious in this patient cohort. Here we report the cases of two brothers with XLA who contracted HCV through contaminated blood products. They were treated with a six month course of Interferon alpha-2b and Ribavirin. We report a sustained virologic response five years after completing treatment.

关键词： Hepatitis C virus X-linked agammaglo- bulinaemia Immunodeficiency Viral hepatitis Cirrhosis Hepatocellular carcinoma

Synthesis of 4-Phenylphthalonitrile by Vapor-Phase Catalytic Ammoxidation of Intermediate 4-Phenyl-<i>o</i>-Tolunitrile: Reaction Kinetics

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Modern Research in Catalysis 2014年第1期3卷 6-11页

作者： g. A. Bagirzade d. B. Tagiyev M. R. Manafov Azerbaijan Medical University Baku Azerbaijan Institute of Chemical Problems Named after Academician M. F. Nagiyev National Academy of Sciences of Azerbaijan Baku Azerbaijan

Kinetic regularities of 4-phenyl-o-tolunitrile ammoxidation on V-Sb-Bi-Zr/γ-Al2O3 oxide catalyst in the temperature interval 633 - 673 K have been studied. It has been established that rates of conversion of 4-phenyl-o-tolu- nitrile into the aimed 4-phenylphthalonitrile and CO2 are described by half-order equation on concentration of substratum and to be independent of the oxygen and ammonia partial pressures. It has been revealed that formation of 4-phenylphthalimide from byproducts is due to hydrolysis of 4-phenylphthalonitrile;carbon dioxide is produced by oxidation of 4-phenyl-o-tolunitrile and decarboxylation of 4-phenylphthalimide, and 4-phenylben- zonitrile is produced from 4-phenyl-o-tolunitrile and 4-phenylphthalimide.

关键词： Catalytic Ammoxidation Partial Pressures 4-Phenylphthalimide Vapor-Phase Electron-donorship Kinetic Measurements

High Throughput Scheduling Algorithms for Input Queued Packet Switches

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Computers, Materials & Continua 2022年第1期70卷 1527-1540页

作者： R.Chithra devi d.Jemi Florinabel Narayanan Prasanth department of IT Dr.Sivanthi Aditanar College of EngineeringTiruchendur628205India department of CSE Dr.Sivanthi Aditanar College of EngineeringTiruchendur628205India School of CSE Vellore Institute of TechnologyVellore632014India

The high-performance computing paradigm needs high-speed switching fabrics to meet the heavy traffic generated by their *** switching fabrics are efficiently driven by the deployed scheduling *** this paper,we proposed two scheduling algorithms for input queued switches whose operations are based on ranking *** first,we proposed a Simple 2-Bit(S2B)scheme which uses binary ranking procedure and queue size for scheduling the ***,the Virtual Output Queue(VOQ)set with maximum number of empty queues receives higher rank than other VOQ’*** simulation,we showed S2B has better throughput performance than Highest Ranking First(HRF)arbitration under uniform,and non-uniform traffic *** further improve the throughput-delay performance,an Enhanced 2-Bit(E2B)approach is *** approach adopts an integer representation for rank,which is the number of empty queues in a VOQ *** simulation result shows E2B outperforms S2B and HRF scheduling algorithms with maximum throughput-delay ***,the algorithms are simulated under hotspot traffic and E2B proves to be more efficient.

关键词： Crossbar switch input queued switch virtual output queue scheduling algorithm high performance computing

Cu–Co–O nano-catalysts as a burn rate modifier for composite solid propellants

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defence Technology（防务技术） 2016年第4期12卷 297-304页

作者： d. Chaitanya Kumar RAO Narendra YAdAV Puran Chandra JOSHI Space Engineering and Rocketry Birla Institute of Technology Mesra Ranchi 835215 India

Nano-catalysts containing copper–cobalt oxides(Cu–Co–O) have been synthesized by the citric acid(CA) complexing method. Copper(II) nitrate and Cobalt(II) nitrate were employed in different molar ratios as the starting reactants to prepare three types of nano-catalysts. Well crystalline nano-catalysts were produced after a period of 3 hours by the calcination of CA–Cu–Co–O precursors at 550 °C. The phase morphologies and crystal composition of synthesized nano-catalysts were examined using Scanning Electron Microscope(SEM), Energy dispersive Spectroscopy(EdS) and Fourier Transform Infrared Spectroscopy(FTIR) methods. The particle size of nano-catalysts was observed in the range of 90 nm–200 nm. The prepared nano-catalysts were used to formulate propellant samples of various compositions which showed high reactivity toward the combustion of HTPB/AP-based composite solid propellants. The catalytic effects on the decomposition of propellant samples were found to be significant at higher temperatures. The combustion characteristics of composite solid propellants were significantly improved by the incorporation of nano-catalysts. Out of the three catalysts studied in the present work, Cu Co-I was found to be the better catalyst in regard to thermal decomposition and burning nature of composite solid propellants. The improved performance of composite solid propellant can be attributed to the high crystallinity, low agglomeration and lowering the decomposition temperature of oxidizer by the addition of Cu Co-I nano-catalyst.

关键词： Metal oxides Nano-catalysts Solid propellant Burn rate Surface morphology Thermal analysis

Safety of the long-term use of proton pump inhibitors

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World Journal of gastroenterology 2010年第19期16卷 2323-2330页

作者： Alan BR Thomson Michel d Sauve Narmin Kassam Holly Kamitakahara division of general Internal Medicine Faculty of Medicine University of Alberta Edmonton AB T6G 2B7 Alberta Canada

The proton pump inhibitors (PPIs) as a class are remarkably safe and effective for persons with peptic ulcer disorders. Serious adverse events are extremely rare for PPIs, with case reports of interstitial nephritis with omeprazole, hepatitis with omeprazole and lansoprazole, and disputed visual disturbances with pantoprazole and omeprazole. PPI use is associated with the development of fundic gland polyps (FgP); stopping PPIs is associated with regression of FgP. In the absence of Helicobacter pylori infection, the long-term use of PPIs has not been convincingly proven to cause or be associated with the progression of pre-existing chronic gastritis or gastric atrophy or intestinal metaplasia. Mild/modest hypergastrinemia is a physiological response to the reduction in gastric acid secretion due to any cause. The long-term use of PPIs has not been convincingly proven to cause enterochromaff in-like cell hyperplasia or carcinoid tumors. PPIs increase the risk of community acquired pneumonia, but not of hospital acquired (nosocomial) pneumonia. There is no data to support particular care in prescribing PPI therapy due to concerns about risk of hip fracture with the long-termuse of PPIs. Long-term use of PPIs does not lead to vitamin B12 def iciencies, except possibly in the elderly, or in persons with Zollinger-Ellison Syndrome who are on high doses of PPI for prolonged periods of time. There is no convincingly proven data that PPIs increase the risk of Clostridium difficile-associated diarrhea in persons in the community. The discontinuation of PPIs may result in rebound symptoms requiring further and even continuous PPI use for suppression of symptoms. As with all medications, the key is to use PPIs only when clearly indicated, and to reassess continued use so that long-term therapy is used judiciously. Thus, in summary, the PPIs are a safe class of medications to use longterm in persons in whom there is a clear need for the maintenance of extensive acid inhibition.

关键词： Acid inhibition drug safety Osteoporosis Pneumonia Enteric infections

An information theoretic method to identify combinations of genomic alterations that promote glioblastoma

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Journal of Molecular Cell Biology 2015年第3期7卷 203-213页

作者： Rachel d.Melamed Jiguang Wang Antonio Iavarone Raul Rabadan department of Systems Biology Columbia University College of Physicians and SurgeonsNew YorkNYUSA department of Biomedical Informatics Columbia University College of Physicians and SurgeonsNew YorkNYUSA Institute for Cancer genetics Columbia University College of Physicians and SurgeonsNew YorkNYUSA department of Pathology and Cell Biology Columbia University College of Physicians and SurgeonsNew YorkNYUSA department of Neurology Columbia University College of Physicians and SurgeonsNew YorkNYUSA

Tumors are the result of accumulated genomic alterations that cooperate synergistically to produce uncontrollable cell *** identifying recurrent alterations among large collections of tumors provides a way to pinpoint genes that endow a selective advantage in oncogenesis and progression,it fails to address the genetic interactions behind this selection process.A non-random pattern of co-mutated genes is evidence for selective forces acting on tumor cells that harbor combinations of these genetic *** existing methods have successfully identified mutually exclusive gene sets,no current method can systematically discover more general genetic *** develop genomic Alteration Modules using Total Correlation(gAMToC),an information theoretic frameworkthat integrates copynumberandmutation datato identify genemodules with any non-randompattern of joint ***,wepresent theSeed-gAMToCprocedure,which uncoversthe mutational context of any putative cancer *** software is publicly *** to glioblastoma multiforme samples,gAMToC results show distinct subsets of co-occurring mutations,suggesting distinct mutational routes to cancer and providing new insight into mutations associated with proneural,proneural/g-CIMP,and classical types of the *** results recapitulate known relationships such as mutual exclusive mutations,place these alterations in the context of other mutations,and find more complex relationships such as conditional mutual exclusivity.

关键词： genomics sequencing entropy copy number cancer cancer genetics