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The host type I interferon response to viral and bacterial infections

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Cell Research 2005年第6期15卷 407-422页

作者： Andrea k. PERRY Department of Microbiology Immunology and Molecular Genetics University of California Los Angeles Los Angeles CA 90095 USA

Type I interferons (IFN) are well studied cytok.nes with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading to IFN productionwere largely unk.own. Toll lik. receptors (TLRs) have emerged as k.y transducers of type I IFN during viral infectionsby recognizing various viral components. Furthermore, much progress has been made in defining the signaling path-ways downstream of TLRs for type I IFN production. TLR7 and TLR9 have become apparent as universally importantin inducing type I IFN during infection with most viruses, particularly by plasmacytoid dendritic cells. New intracellularviral pattern recognition receptors leading to type I IFN production have been identified. Many bacteria can also inducethe up-regulation of these cytok.nes. Interestingly, recent studies have found a detrimental effect on host cells if type IIFN is produced during infection with the intracellular gram-positive bacterial pathogen, Listeria monocytogenes. Thisreview will discuss the recent advances made in defining the signaling pathways leading to type I IFN production.

关键词： type I interferons Toll-lik. receptors pattern-recognition receptors virus infections Listeria monocytogenes signaling mechanisms.

Precipitation variation in the northeastern Tibetan Plateau recorded by the tree rings since 850 AD and its relevance to the Northern Hemisphere temperature

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Science China Earth Sciences 2006年第4期49卷 408-420页

作者： John k. k.tzbach Center for Climatic Research University of Wisconsin-Madison Madison 53706 USA

Three well-dated Sabina Przewalsk.i ring-width chronologies from Dulan, China, have been used to reconstruct annual precipitation (from prior July to current June) variations on the northeast Tibetan Plateau since 850 AD. The reconstructions account of the instrumentally recorded precipitation variance are: 54.7% for the period of 1385-2000AD; 50.5% for 1099-1384AD and 45.7% for 850-1098AD. On the millenary scale, the precipitation variation over this region displays “W” shape, which has three peak. and two valleys. The precipitation is low during 1571-1879 AD, and high during 1880-2000 AD. 1900-2000 AD is the century with the highest precipitation over the northeast Tibetan Plateau in the last 1000 years, and 1962-2000 is the period with the highest pre- cipitation, and the highest variability of precipitation as well in the last 1000 years. The reconstructed series also reveals that the variability of annual precipitation is large when the precipitation is more, and contrarily, variability is small when the precipitation is low. With the temperature increasing obvi- ously in the 20th century, the precipitation in the study region significantly increased too, the variability of precipitation became larger, and drought and flooding occurred more frequently. The yearly tree-ring width (high frequency signal) series in this region reflects the local annually precipitation variation. However, the series with 40-year moving average (low frequency signal) cor- responds to the Northern Hemisphere temperature variations on the decadal to centurial scale. It correlates significantly with seven temperature curves of the Northern Hemisphere in the different time spans. For example, the correlation coefficients with the most temperature curves are around 0.9 during the period of 1852-1982 AD. In general, the temperature and the precipitation change syn- chronously in the Dulan region. It means that low temperature corresponds to low precipitation, andvice versa. This relations

关键词： Dulan China, Sabina Przewalsk.i, annual precipitation, the Northern Hemisphere temperature.

Joint rate control and scheduling for wireless uplink.video streaming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 801-810页

作者： k.TSAGGELOS Aggelos k. Department of Electrical Engineering & Computer Science Northwestern University Evanston Illinois 60208 USA

We solve the problem of uplink.video streaming in CDMA cellular network. by jointly designing the rate control and scheduling algorithms. In the pricing-based distributed rate control algorithm, the base station announces a price for the per unit average rate it can support, and the mobile devices choose their desired average transmission rates by balancing their video quality and cost of transmission. Each mobile device then determines the specific video frames to transmit by a video summarization process. In the time-division-multiplexing (TDM) scheduling algorithm, the base station collects the information on frames to be transmitted from all devices within the current time window, sorts them in increasing order of deadlines, and schedules the transmissions in a TDM fashion. This joint algorithm tak.s advantage of the multi-user content diversity, and maximizes the network.total utility (i.e., minimize the network.total distortion), while satisfying the delivery deadline constraints. Simulations showed that the proposed algorithm significantly outperforms the constant rate provision algorithm.

关键词： Video streaming, Pricing, Uplink communications, CDMA, Cross-layer design, Video summarization

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The neutron star zoo

Frontiers of physics 2013年第6期8卷 679-692页

作者： Alice k. Harding Astrophysics Science Division NASA Goddard Space Flight Center Greenbelt MD 20771 USA

Neutron stars are a very diverse population, both in their observational and their physical properties. They prefer to radiate most of their energy at X-ray and gamma-ray wavelengths. But whether their emission is powered by rotation, accretion, heat, magnetic fields or nuclear reactions, they are all different species of the same animal whose magnetic field evolution and interior composition remain a mystery. This article will broadly review the properties of inhabitants of the neutron star zoo, with emphasis on their high-energy emission.

关键词： stars neutron stars pulsars binary stars

Elimination of boundary effect for laminated overburden model in pillar stability analysis

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Journal of Central South University 2016年第6期23卷 1468-1473页

作者：张鹏 k. A. Heasley Carlson Software Watertown MA 02472 USA Department of Mining Engineering West Virginia University WV 26505 USA

The laminated overburden model(La Model)has been widely used for pillar design and stability *** a boundary element program,the La Model program is sensitive to the boundary condition,which should be considered before creating the *** eliminate the boundary effect in a La Model pillar stability analysis,a suitable boundary buffer zone is needed around the model *** radius of influence(R)and the abutment load extent(D)are two major factors that affect the stresses and displacements calculated in LaM *** determine the optimum buffer zone extent,a database of case histories was analyzed using the La Model *** for R and D were varied until a buffer zone having negligible influence on the pillar stability factor(SF)of the active mining zone(AMZ)was determined.

关键词： pillar stability boundary effect LaModel numerical simulation room-and-pillar

Unveiling the impact:COVID-19's influence on bacterial resistance in the k.ngdom of Bahrain

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World Journal of Virology 2025年第1期14卷 83-98页

作者： Nermin k.Saeed Safiya k.Almusawi Noor A Albalooshi Mohammed Al-Beltagi Medical Microbiology Section Department of PathologySalmaniya Medical ComplexGovernmental HospitalsManama 12Bahrain Medical Microbiology Section Department of PathologyRoyal College of Surgeons in Ireland-Medical University of BahrainBusaiteen 15503MuharraqBahrain Department of Paediatrics Faculty of MedicineTanta UniversityTanta 31511AlghrabiaEgypt Department of Pediatric University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671AlgharbiaBahrain

BACk.ROUND Antibiotic resistance is a growing global health threat,and understanding local trends in bacterial isolates and their susceptibility patterns is crucial for effective infection control and antimicrobial *** coronavirus disease 2019(COVID-19)pandemic has introduced additional complexities,potentially influencing these *** To analyze trends in bacterial isolates and their antibiotic susceptibility patterns at Salmaniya Medical Complex from 2018 to 2023,with a specific focus on the impact of the COVID-19 pandemic on these *** A retrospective analysis of microbiological data was conducted,covering the period from 2018 to *** study included k.y bacterial pathogens such as Escherichia coli(***),k.ebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa,and Staphylococcus aureus,among *** antibiotic susceptibility profiles of these isolates were assessed using standard laboratory *** contextualize the findings,the findings were compared with similar studies from other regions,including China,India,Romania,Saudi Arabia,the United Arab Emirates,Malaysia,and United *** The study revealed fluctuating trends in the prevalence of bacterial isolates,with notable changes during the COVID-19 *** example,a significant increase in the prevalence of Staphylococcus aureus was observed during the pandemic years,while the prevalence of *** showed a more variable *** resistance rates varied among the different pathogens,with a concerning rise in resistance to commonly used antibiotics,particularly among k.ebsiella pneumoniae and ***,the study identified an alarming increase in the prevalence of multidrug-resistant(MDR)strains,especially within k.ebsiella pneumoniae and *** *** impact of the COVID-19 pandemic on these trends was evident,with shifts in the frequency,resistance patterns,and the emergence of MDR bacteria among several k.y ***

关键词： Multidrug-resistant organisms Antibiotic susceptibility COVID-19 pandemic Antimicrobial stewardship Bacterial isolates Salmaniya Medical Complex Bahrain

Solvent effects on hydrogen bonding between primary alcohols and esters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1928-1931页

作者： DHARMALINGAM k. RAMACHANDRAN k. SIVAGURUNATHAN P. Department of Physics Annamalai University Annamalai Nagar 608002 Tamilnadu India

The interaction by hydrogen bond formation of some primary alcohols （ l-heptanol, l-octanol and l-decanol） with esters （methyl methacrylate, ethyl methacrylate and butyl methacrylate） was investigated in non-polar solvents viz., n-heptane, CC14 and benzene by means of FTIR spectroscopy. Formation constants and free energy changes of complex formation were determined. The dependence of the equilibrium constants and free energy changes of complex formation on the alk.l chain length of both the alcohols and esters are discussed. The solvent interaction between the solute and solvent. effect on the hydrogen bond formation is discussed in terms of specific

关键词： FTIR spectroscopy Primary alcohols Esters Hydrogen bonding Solvent effect

A cellular automata traffic flow modeling of desired speed variability

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Chinese Physics B 2013年第1期22卷 574-577页

作者： k. Bentaleb k. Jetto H. Ez-Zahraouy A. Benyoussef Laboratoire de Magnétisme et de Physique des Hautes Energies associéau CNRST (URAC 12) Département de physique B.P. 1014 Facultédes sciences Université Mohammed V Agdal Rabat Morocco Ecole Hassania des Travaux Publics k. 7 Route d'El Jadida BP8108 Oasis Casablanca Morocco Institute of Nanomaterials and Nanotechnologies INANOTECH MACsIR Rabat Morocco Hassan II Academy of Science and Technology Rabat Morocco

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. However, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. E 79 066110 （2009）]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate tak.s higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtak.ng.

关键词： traffic celluar automata satisfaction coefficient desired speed

On the invariance of time-dependent Hamilton's functions

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Acta Mechanica Sinica 2005年第5期21卷 511-513页

作者： Q. k. Ghori Department of Mathematics COMSATS Institute of Information TechnologyIslamabad Pakistan

The general framework.of Poincarè＇s formalism is used to establish the connection between conservation laws and invariance properties of Hamilton＇s function under infinitesimal transformations when these laws and t... 详细信息

关键词： Conservation law . Poincarè's formalism .Infinitesimal transformation