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World journal of Gastroenterology 2006年第46期12卷 7547-7548页

作者： Wichian Apiratpracha jin Kee Ho james j Powell Eric M Yoshida British Columbia Transplant Society The University of British Columbia Vancouver BC Canada Division of Gastroenterology Department of Medicine The University of British Columbia Vancouver BC Canada Department of Surgery The University of British Columbia Vancouver BC Canada

A 67-year-old woman underwent an orthotopic liver transplantation for end stage liver disease secondary to chronic autoimmune hepatitis. She developed sudden massive hematochezia on post-operative day 23 with hemodynamic compromise. The source of hemorrhage was found at colonoscopy after careful irrigation and inspection to be a dieulafoy lesion situated just proximal to the anorectal junction. Hemostasis was achieved with epinephrine injection and thermal coagulation.

关键词： Bleeding Anorectal Dieulafoy Rectum

Diffusion of lithium ions in Lithium-argyrodite solid-state electrolytes

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npj Computational Materials 2020年第1期6卷 326-335页

作者： Ardeshir Baktash james C.Reid Tanglaw Roman Debra j.Searles Centre for Theoretical and Computational Molecular Science Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt Lucia 4072 QLDAustralia School of Mathematics and Physics The University of QueenslandSt Lucia 4072 QLDAustralia School of Physics The University of SydneyCamperdown 2006 NSWAustralia School of Chemistry and Molecular Biosciences The University of QueenslandSt Lucia 4072 QLDAustralia

The use of solid-state electrolytes to provide safer,next-generation rechargeable batteries is becoming more feasible as materials with greater stability and higher ionic diffusion coefficients are ***,accurate determination of diffusion coefficients in solids is problematic and reliable calculations are highly sought-after to understand how their structure can be modified to improve their *** this paper we compare diffusion coefficients calculated using nonequilibrium and equilibrium ab initio molecular dynamics simulations for highly diffusive solid-state electrolytes,to demonstrate the accuracy that can be ***,we show that ab initio nonequilibrium molecular dynamics can be used to determine diffusion coefficients when the diffusion is too slow for it to be feasible to obtain them using ab initio equilibrium simulations.

关键词： diffusion nonequilibrium feasible

The Shishugou Fauna of the Middle-Late jurassic Transition Period in the junggar Basin of Western China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1115-1135页

作者： XU Xing james M.CLARK David A.EBERTH Philip j.CURRIE Centre for Vertebrate Evolutionary Biology Yunnan UniversityKunming 650500China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Department of Biological Sciences George Washington UniversityWashington DC20052USA Royal Tyrrell Museum of Palaeontology Box 7500DrumhellerAlberta T0J 0Y0Canada Department of Biological Sciences University of Alberta 116 Street and 85 AvenueEdmontonAB T6G 2R3Canada

The Middle-Late jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from this time is relatively *** Shishugou Fauna of this period has recently produced significant fossil remains of dinosaurs and other vertebrate groups,some representing the earliest known members of several dinosaurian groups and other vertebrate groups and some representing the best-known specimens of their *** discoveries are significant for our understanding of the origin and evolution of several vertebrate *** dating indicates that the fauna is aged approximately 159-164 *** with other similarly-aged terrestrial faunas such as Shaximiao and Yanliao show both taxonomic similarities and differences between these faunas and indicate that the junggar deposits might have preserved the most complete vertebrate fossil record for a Middle-Late jurassic Laurasian terrestrial fauna.

关键词： Middle-Late jurassic Shishugou Fauna Shishugou Formation terrestrial ecosystem Shaximiao Yanliao junggar Basin

Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

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Current Zoology 2011年第2期57卷 187-196页

作者： Christopher james CLARK Peabody Museum of Natural History Yale University PO Box 208106 New Haven CT 06511 USA Museum of Vertebrate Zoology University of California- Berkeley Berkeley CA USA

Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone （hfl）, a low frequency tone （lft）, and atonal sound pulses （asp）, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices （tail-feathers） of wild males impaired production of the lft and asp but not the hfl or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds sitlfilar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism .

关键词： Calliope Hummingbird Courtship Multicomponent Signal Sonation Wind Tunnel

Accurate Gain Flattening Filters Manufactured by Optical Compensation Monitoring Method

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光学学报 2003年第S1期23卷 -页

作者： j. j. Pan james Guo joy jiang Lightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USALightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USALightwaves 2020 Inc. 1323 Great Mall Drive Milpitas CA 95035 USA

GFFs with less than 0.4 dB peak-to-peak error functions are routinely fabricated using commercially available coating machines by utilizing the natural error compensation mechanism of wavelength variable turning point... 详细信息

关键词： that in of on by GFF Accurate Gain Flattening Filters Manufactured by Optical Compensation Monitoring Method for than

Mice with a heterozygous Lrp6 deletion have impaired fracture healing

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Bone Research 2016年第2期4卷 101-109页

作者： Travis A Burgers juan F Vivanco juraj zahatnansky Andrew j Vander Moren james j Mason Bart O Williams Center for Cancer and Cell Biology Program for Skeletal Disease and Tumor Microenvironment Van Andel Research Institute Grand Rapids MhUSA Faculfad de Ingenieria y Ciencias Adolfo Ib6fiez University Vifia del Mar Chile padnos College of Engineering and Computing Grand Valley State University Grand Rapids MI USA

Bone fracture non-unions, the failure of a fracture to heal, occur in 10%-20% of fractures and are a costly and debilitating clinical problem. The Wnt/fl-catenin pathway is critical in bone development and fracture healing. Polymorphisms of linking low-density lipoprotein receptor-related protein 6 （LRP6）, a Wnt-binding receptor, have been associated with decreased bone mineral density and fragility fractures, although this remains controversial. Mice with a homozygous deletion of Lrp6 have severe skeletal abnormalities and are not viable, whereas mice with a heterozygous deletion have a combinatory effect with Lrp5 to decrease bone mineral density. As fracture healing closely models embryonic skeletal development, we investigated the process of fracture healing in mice heterozygous for Lrp6 （Lrp6~/-） and hypothesized that the heterozygous deletion of Lrp6 would impair fracture healing. Mid-diaphyseal femur fractures were induced in Lrp6~^- mice and wild-type controls （Lrp6~/~）. Fractures were analyzed using micro-computed tomography （~CT） scans, biomechanical testing, and histological analysis. Lrp6~/- mice had significantly decreased stiffness and strength at 28 days post fracture （PF） and significantly decreased BV/TV, total density, immature bone density, and mature area within the callus on day-14 and -21 PF; they had significantly increased empty callus area at days 14 and 21 PF. Our results demonstrate that the heterozygous deletion of Lrp6 impairs fracture healing, which suggests that Lrp6 has a role in fracture healing.

关键词： bone Mice with a heterozygous Lrp6 deletion have impaired fracture healing

Simulated Microbe Removal around Finger Rings Using Different Hand Sanitation Methods

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International journal of Oral Science 2009年第3期1卷 136-142页

作者： Archana A. Alur Madhavi j. Rane james P. Scheetz Douglas j. Lorenz Lawrence Gettleman Ballard High School Louisville Kentucky USA School of Medicine University of Louisville Louisville Kentucky USA School of Dentistry University of Louisville Louisville Kentucky USA School of Public Health & Information Sciences University of Louisville Louisville Kentucky USA

Aim It is our opinion that the CDC and the WHO have underestimated cross-contamination under examination gloves in dental clinics while wearing jewelry, such as finger rings. These agencies only ＂recommend＂ removing jewelry, and only washing hands for 15 seconds with soap and warm water before donning gloves. This study examined several washing procedures and finger rings using simulated microbes. Methodology A gloved robber hand manikin was made and fitted with a flesh disposable vinyl glove. Four fingers were fitted with rings or no ring, dusted with simulated microbes, and washed with a scrub brush for 5, 15, and 25 seconds under 20℃ and 40℃ water alone, or with liquid hand soap. Light levels （in lux） of fluorescent powder before and after washing were measured and delta scores calculated for changes in light levels, equivalent to effectiveness of hand washing procedures. A full-factorial, 3-factor analysis of variance （ANOVA） was used to test for differences among levels of the three study factors-time, temperature, and soap use. Tukey＇s post hoc honestly significant difference （HSD） test was applied to significant factors to examine pair-wise differences between factor levels. Results It was found that the longer the hands with rings were washed with a scrub brush under flowing water, the more simulated microbes were removed. By 25 seconds, all methods were essentially the same. Simulated microbes were more difficult to remove from the palm compared to the back of the hand. The liquid hand soap used in this study was more effective with warm water than cold. When given a choice of washing with cold water up to 15 seconds, it would be preferable not to use soap to remove simulated microbes. Qualitatively, the outer surface of finger rings were more effectively cleaned than the crevice below the ring, and the ring with a stone setting appeared to accumulate and retain simulated microbes more than other rings. Conclusion The most effective treatment was washing wi

关键词： dental exam gloves finger ring jewelry crosscontamination hand hygiene microbes fluorescent powder dental health care workers

Experimental study on the degree and damage-control mechanisms of fuzzy-ball-induced damage in single and multi-layer commingled tight reservoirs

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Petroleum Science 2023年第6期20卷 3598-3609页

作者： Chinedu j.Okere james j.Sheng Li-Kun Fan Xiao-Wei Huang Li-Hui Zheng Pan-Feng Wei Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityTXUSA College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China China Changqing Oilfield Company CNPCXi'an710018ShaanxiChina Beijing LihuiLab Energy Technology Co. Ltd.Beijing102200China

Fuzzy-ball working fluids(FBWFs)have been successfully applied in different development phases of tight *** reports revealed that FBWFs satisfactorily met all the operational and reservoir damage control requirements during their ***,the damage-control mechanisms and degree of formation damage caused by fuzzy-ball fluids have not been investigated in lab-scale studies so *** this study,the degree of fuzzy-ball-induced damage in single-and double-layer reservoirs was evaluated through core flooding experiments that were based on permeability and flow rate ***,its damage mechanisms were observed via scanning electron microscope and energy-dispersive spectroscopy *** results show that:(1)For single-layer reservoirs,the FBWF induced weak damage on coals and medium-to-weak damage on sandstones,and the difference of the damage in permeability or flow rate index on coals and sandstones is below 1%.Moreover,the minimum permeability recovery rate was above 66%.(2)For double-layer commingled reservoirs,the flow rate index revealed weak damage and the overall damage in double-layer was lower than the single-layer reservoirs.(3)There is no significant alteration in the microscopic structure of fuzzy-ball saturated cores with no evidence of fines *** dissolution of lead and sulfur occurred in coal samples,while tellurium in sandstone,aluminum,and magnesium in ***,the precipitation of aluminum,magnesium,and sodium occurred in sandstone but no precipitates found in coal and *** temporal plugging and dispersion characteristics of the FBWFs enable the generation of reservoir protection layers that will minimize formation damage due to solid and fluid invasion.

关键词： Drilling Fracture Fuzzy-ball fluids Formation damage analysis Muti-layer tight reservoirs Permeability damage index Flow rate damage index

Transformer2 proteins protect breast cancer cells from accumulating replication stress by ensuring productive splicing of checkpoint kinase 1

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 186-195页

作者： Andrew Best Katherine james Gerald Hysenaj Alison Tyson-Capper David j. Elliott Institute of Genetic Medicine Newcastle University Newcastle NE1 3BZ UK Interdisciplinary Computing and Complex BioSystems Research Group and Centre for Bacterial Cell Biology Newcastle University Newcastle NE1 3BZ UK Institute for Cellular Medicine Newcastle University Newcastle NE2 4HH UK

Increased expression levels of the RNA splicing regulator Transformer2fl （abbreviated Tra2fl） have been reported in several types of cancer. Recent work has revealed an intimate cross-regulation between Tra2fl and the highly similar Tra2a protein in human breast cancer cells, though these two proteins are encoded by separate genes created by a gene duplication that occurred over 500 million years ago. This cross-regulation involves splicing control of a special class of exons, called poison exons. Down-regulation of Tra2fl reduces splicing inclu- sion of a poison exon in the mRNA encoding Tra2a, thereby up-regulating Tra2a protein expression. This buffers any splicing changes that might be caused by individual depletion of Tra2fl alone. Discovery of this cross-regulation pathway, and its by-pass by joint deple- tion of both human Tra2 proteins, revealed Tra2 proteins are essential for breast cancer cell viability, and led to the identification of important targets for splicing control. These exons include a critical exon within the checkpoint kinase 1 （CHK1） gene that plays a crucial function in the protection of cancer cells from replication stress. Breast cancer cells depleted for Tra2 proteins have reduced CHK1 protein levels and accumulate DNA damage. These data suggest Tra2 proteins and/or their splicing targets as possible cancer drug targets.

关键词： RNA splicing gene expression breast cancer,DNA damage CHK1

Discussion of liquid threshold pressure gradient

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Petroleum 2017年第2期3卷 232-236页

作者： Xiukun Wang james j.Sheng Texas Tech University USA Southwest Petroleum University China

Some authors believe that a minimum pressure gradient(called threshold pressure gradient(TPG))is required before a liquid starts to flow in a porous *** a tight or shale oil formation,this TPG phenomenon becomes more important,as it is more difficult for a fluid to *** this paper,experimental data on TPG published in the literature are carefully *** we found is that a very low flow velocity corresponding to a very low pressure gradient cannot be measured in the *** can only be done above some measurable flow *** these flow velocities and their corresponding pressure gradients are plotted in an XY plot and extrapolated to zero velocity,a non-zero pressure gradient corresponds to this zero *** non-zero pressure gradient is called threshold pressure gradient in the ***,in the regime of very low velocity and very low pressure gradient,the data gradually approach to the origin of the plot,demonstrating a non-linear relationship between the pressure gradient and the *** the data do not approach to a point of zero velocity and a threshold pressure ***,the concept of threshold pressure gradient is a result of data misinterpretation of available experimental *** correct interpretation is that there are two flow regimes:nonlinear flow regime(non-Darcy flow regime)when the pressure gradients are low,and linear flow regime(Darcy flow regime)when the pressure gradient is intermediate or *** nonlinear flow regime starts from the origin *** the pressure gradient is increased,the curve becomes a straight line demonstrating the linear flow *** have verified our views by first analyzing the causes of non-Darcy flow,and then systematically analyzed typical experimental data and correlations in the *** conclude that TPG does not *** also use several counter examples to support our conclusion.

关键词： Low velocity non-Darcy flow Threshold pressure gradient Shale oil reservoirs Tight oil reservoirs