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Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation

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Integrative Zoology 2012年第1期7卷 48-60页

作者： paul A.IAIZZO Timothy G.LASKE Henry J.HARLOW Carolyn b.McCLAY David L.GARSHELIS Department of Surgery University of Minnesota Medtronic Inc Department of Zoology and Physiology University of WyomingLaramie Minnesota Department of Natural Resources USA

Even mildly hypothermic body or limb temperatures can retard healing processes in *** this,we observed that hibernating American black bears(Ursus americanus Pallas,1780)elicit profound abilities in mounting inflammatory responses to infection and/or foreign *** addition,they resolve injuries during hibernation while maintaining mildly hypothermic states(30–35°C)and without eating,drinking,urinating or *** describe experimental studies on free-ranging bears that document their abilities to completely resolve cutaneous cuts and punctures incurred during or prior to *** induced small,full-thickness cutaneous wounds(biopsies or incisions)during early denning,and re-biopsied sites 2–3 months later(near the end of denning).Routine histological methods were used to characterize these skin *** biopsied sites with respect to secondary intention(open circular biopsies)and primary intention(sutured sites)healed,with evidence of initial eschar(scab)formation,completeness of healed epidermis and dermal layers,dyskeratosis(inclusion cysts),and abilities to produce hair *** healing abilities of hibernating black bears are a clear survival advantage to animals injured before or during *** are known to have elevated levels of hibernation induction trigger(delta-opioid receptor agonist)and ursodeoxycholic acid(major bile acid within plasma,mostly conjugated with taurine)during hibernation,which may relate to these wound-healing *** research as to the underlying mechanisms of wound healing during hibernation could have applications in human *** approaches may be found to improve healing for malnourished,hypothermic,diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries.

关键词： black bear denning hair growth healing hibernation histology scarring

Seismic anisotropy of upper mantle in eastern Tibetan Plateau and related crust-mantle coupling pattern

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Science China Earth Sciences 2007年第8期50卷 1150-1160页

作者： paul SILVER Lucy FLESCH Carnegie Institution of Washington Washington DC 200015 USA

by using the polarization analysis of teleseismic SKS waveform data recorded at 116 seismic stations which respectively involved in China National Digital Seismograph Network, and Yunnan, Sichuan, Gansu and Qinghai regional digital networks, and portable broadband seismic networks deployed in Sichuan, Yunnan and Tibet, we obtained the SKS fast-wave direction and the delay time between fast and slow waves of each station by use of the stacking analysis method, and finally acquired the fine image of upper mantle anisotropy in the eastern Tibetan Plateau and its adjacent regions. We analyzed the crust-mantle coupling deformation on the basis of combining the GPS observation results and the upper mantle anisotropy distribution in the study area. The Yunnan region out of the plateau has dif-ferent features of crust-mantle deformation from the inside plateau. There exists a lateral transitional zone of crust-mantle coupling in the eastern edge of the Tibetan Plateau, which is located in the region between 26° and 27°N in the west of Sichuan and Yunnan. To the south of transitional zone, the fast-wave direction is gradually turned from S60°―70°E in southwestern Yunnan to near EW in south-eastern Yunnan. To the north of transitional zone in northwestern Yunnan and the south of western Sichuan, the fast-wave direction is nearly NS. From crust to upper mantle, the geophysical parameters (e.g. the crustal thickness, the bouguer gravity anomaly, and tectonic stress direction) show the feature of lateral variation in the transitional zone, although the fault trend on the ground surface is inconsis-tent with the fast-wave direction. This transitional zone is close by the eastern Himalayan syntaxis, and it may play an important role in the plate boundary dynamics.

关键词： upper mantle anisotropy SKS wave fast-wave direction crust-mantle coupling lithospheric deformation

Increased Light, Moderate, and Severe Clear-Air Turbulence in Response to Climate Change

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Advances in Atmospheric Sciences 2017年第5期34卷 576-586页

作者： paul D. WILLIAMS Department of Meteorology University of Reading Reading RG6 6BB United Kingdom

Anthropogenic climate change is expected to strengthen the vertical wind shears at aircraft cruising altitudes within the atmospheric jet streams. Such a strengthening would increase the prevalence of the shear instabilities that generate clear-air turbulence. Climate modelling studies have indicated that the amount of moderate-or-greater clear-air turbulence on transatlantic flight routes in winter will increase significantly in future as the climate changes. However,the individual responses of light,moderate,and severe clear-air turbulence have not previously been studied,despite their importance for aircraft operations. Here,we use climate model simulations to analyse the transatlantic wintertime clear-air turbulence response to climate change in five aviation-relevant turbulence strength categories. We find that the probability distributions for an ensemble of 21 clear-air turbulence diagnostics generally gain probability in their right-hand tails when the atmospheric carbon dioxide concentration is doubled. by converting the diagnostics into eddy dissipation rates,we find that the ensembleaverage airspace volume containing light clear-air turbulence increases by 59%(with an intra-ensemble range of 43%–68%),light-to-moderate by 75%(39%–96%),moderate by 94%(37%–118%),moderate-to-severe by 127%(30%–170%),and severe by 149%(36%–188%). These results suggest that the prevalence of transatlantic wintertime clear-air turbulence will increase significantly in all aviation-relevant strength categories as the climate changes.

关键词： turbulence climate change aviation jet stream

Microbiota-host interplay at the gut epithelial level,health and nutrition

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Journal of Animal Science and biotechnology 2017年第2期8卷 327-334页

作者： Jean-paul Lallès Division of Human Nutrition Division INRA Clermont-Ferrand France Human Nutrition Research Center-West Nantes France

Growing evidence suggests the implication of the gut microbiota in various facets of health and disease. In this review, the focus is put on microbiota-host molecular cross-talk at the gut epithelial level with special emphasis on two defense systems： intestinal alkaline phosphatase（IAP） and inducible heat shock proteins（iHSPs）. both IAP and iHSPs are induced by various microbial structural components（e.g. lipopolysaccharide, flagellin, CpG DNA motifs）,metabolites（e.g. n-butyrate） or secreted signal molecules（e.g., toxins, various peptides, polyphosphate）. IAP is produced in the small intestine and secreted into the lumen and in the interior milieu. It detoxifies microbial components by dephosphorylation and, therefore, down-regulates microbe-induced inflammation mainly by inhibiting NF-κb pro-inflammatory pathway in enterocytes. IAP gene expression and enzyme activity are influenced by the gut microbiota. Conversely, IAP controls gut microbiota composition both directly, and indirectly though the detoxification of pro-inflammatory free luminal adenosine triphosphate and inflammation inhibition. Inducible HSPs are expressed by gut epithelial cells in proportion to the microbial load along the gastro-intestinal tract. They are also induced by various microbial components, metabolites and secreted molecules. Whether iHSPs contribute to shape the gut microbiota is presently unknown. both systems display strong anti-inflammatory and anti-oxidant properties that are protective to the gut and the host. Importantly, epithelial gene expressions and protein concentrations of IAP and iHSPs can be stimulated by probiotics, prebiotics and a large variety of dietary components, including macronutrients（protein and amino acids, especially L-glutamine, fat, fiber）, and specific minerals（e.g. calcium）and vitamins（e.g. vitamins K1 and K2）. Some food components（e.g. lectins, soybean proteins, various polyphenols） may inhibit or disturb these systems. The general cel ular and molecula

关键词： Diet Gut Inducible heat shock protein Inflammation Intestinal alkaline phosphatase Microbiota

CR Geometry in 3-D(Dedicated to Professor Haim brezis with admiration)

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Chinese Annals of Mathematics,Series b 2017年第2期38卷 695-710页

作者： paul C.YANG department of mathematics princeton universityFine HallW ashington RoadPrinceton NJ 08544 USA.

CR geometry studies the boundary of pseudo-convex manifolds. by concentrating on a choice of a contact form, the local geometry bears strong resemblence to conformal geometry. This paper deals with the role conformally invariant operators such as the Paneitz operator plays in the CR geometry in dimension three. While the sign of this operator is important in the embedding problem, the kernel of this operator is also closely connected with the stability of CR structures. The positivity of the CR-mass under the natural sign conditions of the Paneitz operator and the CR Yamabe operator is discussed. The CR positive mass theorem has a consequence for the existence of minimizer of the CR Yamabe problem. The pseudo-Einstein condition studied by Lee has a natural analogue in this dimension, and it is closely connected with the pluriharmonic *** author discusses the introduction of new conformally covariant operator P-prime and its associated Q-prime curvature and gives another natural way to find a canonical contact form among the class of pseudo-Einstein contact forms. Finally, an isoperimetric constant determined by the Q-prime curvature integral is discussed.

关键词： Paneitz operator, Embedding problem, Yamabe equation, Mass,P-prime, Q-prime curvature

Two pedogenic models for paleoclimatic records of magnetic susceptibility from Chinese and Siberian loess

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Science China Earth Sciences 2008年第2期51卷 284-293页

作者： paul HESSE Jiri CHLACHULA Department of Physical Geography Macquarie University NSW 2109 Australia Key Laboratory of Desert and Desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou 730000 China

The magnetic susceptibility (MS) of Chinese loess showing a general proportional relationship to pedogenic grade has been widely recognized and used for reconstruction of paleoclimate by Quaternary scientists. The in-... 详细信息

关键词： Siberian loess Chinese loess paleoclimate magnetic susceptibility magnetic mineralogy environmental magnetism

A sweeping preconditioner for Yee＇s finite difference approximation of time-harmonic Maxwell＇s equations

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Frontiers of Mathematics in China 2012年第2期7卷 347-363页

作者： paul TSUJI Lexing YING ICES University of Texas at Austin Austin TX 78712 USA Department of Mathematics University of Texas at Austin Austin TX 78712 USA

This paper is concerned with the fast iterative solution of linear systems arising from finite difference discretizations in electromagnetics. The sweeping preconditioner with moving perfectly matched layers previously developed for the Helmholtz equation is adapted for the popular Yee grid scheme for wave propagation in inhomogeneous, anisotropic media. Preliminary numerical results are presented for typical examples.

关键词： Electromagnetic scattering Yee grid finite difference methods perfectly matched layers LDLT factorizations multifrontal method wave propagation in inhomogeneous and anisotropic media matrix preconditioners

Advances in newly developing therapy for chronic hepatitis C virus infection

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Frontiers of Medicine 2014年第2期8卷 166-174页

作者： paul J. Pockros Division of Gastro/Hepatology Scripps Clinic 10666 N Torrey Pines Road N203 La Jolla CA 92067 USA

Chronic hepatitis C virus （HCV） infection afflicts a reported 170 million people worldwide and is often complicated by cirrhosis and hepatocellular carcinoma. Morbidity and mortality are decreased with the successful treatment of chronic HCV infection. Increased understanding of the HCV has allowed further development of new direct-acting antiviral （DAA） agents against the HCV and has also allowed the development of IFN-free oral treatment regimens. In late 2013 the first nucleotide polymerase inhibitor regimen with RbV alone for genotypes 2/3 and in combination with a 12-week regimen of PEG-IFN ＋ RbV for genotypes 1, 4 was approved for use in the US. A number of promising new DAA regimens which are IFN-free are in phase 3 development and the first will likely be approved for use in the US in 2014. The currently approved regimens are discussed in detail and currently available data on future regimens are reviewed herein.

关键词： direct-acting antiviral (DAA) nucleotide polymerase inhibitors protease inhibitors

Performance measurement of sericin-coated silks during aging

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Science China Chemistry 2011年第6期54卷 1011-1016页

作者： ZHANG XiaoMei WYETH paul School of Archaeology and Museology Peking University Beijing 100871 China clo Centre for Textile Conservation and Technical Art History University of Glasgow Glasgow G12 8QH UK

Silks are among the most precious ancient and historic artefacts worldwide. While washing removes the natural gum from the fibres during the fabrication of most silk textiles, for a small proportion of historic silks some or perhaps all of the sericin still remains. This paper investigated the effect of sericin coating on the aging of silk fibroin by means of ATR and tensile testing. The results show that sericin can provide some extent of protection from light and heat aging. However, in high humidity environments degummed and ungummed silk aged at the same rate because of leaching of sericin. Silk degraded at faster rate and more extensively in a moist environment. ATR could give very useful information about the aging of silk. The ATR-derived crystallinity index is good at tracing the aging factor and extent of silk deterioration. Alanine and tyrosine within fibroin, as estimated by ATR spectroscopy, are very sensitive to light, but not to heat and water. The ATR absorbance intensity ratio Iamide Ⅲ/ Iamide I is very useful for deterioration evaluation of archaeological silk objects. As a high humidity resulted in the leaching of silk, it is suggested for sericin-coated silk in collections, that not only wet cleaning is harmful, but also that storage or display in a high RH environment would be detrimental.

关键词： attenuated total reflectance infrared spectroscopy archaeological silk sericin