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Gamma-ray bursts and their links with supernovae and cosmology

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Research in Astronomy and Astrophysics 2012年第8期12卷 1139-1161页

作者： Peter mszros Neil Gehrels Center for Particle and Gravitational Astrophysics Dept.of Astronomy&Astrophysics and Dept.of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA Astrophysics Science Division NASA Goddard Space Flight CenterGreenbeltMD 20771USA

Gamma-ray bursts are the most luminous explosions in the Universe, whose origin and mechanism are the focus of intense interest. They appear connected to su- pernova remnants from massive stars or the merger of their remnants, and their bright- ness makes them temporarily detectable out to the largest distances yet explored in the universe. After pioneering breakthroughs from space and ground experiments, their study is entering a new phase with observations from the recently launched Fermi satellite, as well as the prospect of detections or limits from large neutrino and gravitational wave detectors. The interplay between such observations and theoretical models of gamma-ray bursts is reviewed, and cosmology. as well as their connections to supernovae

关键词： gamma-ray sources -- gamma-ray bursts -- cosmic rays -- neutrinos-- supernovae -- cosmology -- intergalactic medium

Creeping fat and gut microbiota in Crohn’s disease

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World Journal of Gastroenterology 2025年第1期31卷 16-23页

作者： Ana EV Quaglio Daniéla O magro marcello Imbrizi Ellen cs De Oliveira Luiz C Di Stasi Ligia Y Sassaki Verum Ingredients Botucatu Technology ParkBotucatu 18605-525São PauloBrazil Department of Surgery Faculty of Medical SciencesState University of CampinasCampinas 13083-970São PauloBrazil Department of Gastroenterology Faculty of Medical SciencesUniversity of CampinasCampinas 13083-970São PauloBrazil Department of Internal medicine Medical SchoolSão Paulo State UniversityBotucatu 18618-686São PauloBrazil Department of Biophysics and Pharmacology Institute of BiosciencesSão Paulo State UniversityBotucatu 18618-689São PauloBrazil

In this article,we explored the role of adipose tissue,especially mesenteric adipose tissue and creeping fat,and its association with the gut microbiota in the pathophysiology and progression of Crohn’s disease(CD).CD is a form of inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract,influenced by genetic predisposition,gut microbiota dysbiosis,and environmental *** microbiota plays a crucial role in modulating immune response and intestinal inflammation and is associated with the onset and progression of ***,visceral adipose tissue,particularly creeping fat,a mesenteric adipose tissue characterized by hypertrophy and fibrosis,has been implicated in CD pathogenesis,inflammation,and *** bacteria from the gut microbiota may translocate into mesenteric adipose tissue,contributing to the formation of creeping fat and influencing CD *** creeping fat may be a protective barrier against bacterial invasion,its expansion can damage adjacent tissues,leading to *** gut microbiota through interventions such as fecal microbiota transplantation,probiotics,and prebiotics has shown potential in managing ***,more research is needed to clarify the mechanisms linking gut dysbiosis,creeping fat,and CD progression and develop targeted therapies for microbiota modulation and fat-related complications in patients with CD.

关键词： Creeping fat mesenteric adipose tissue Gut microbiota Crohn’s disease Inflammatory bowel disease

Vanishing torsion of parametric curves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 593-595页

作者： JUHsz Imre Department of Descriptive Geometry University of MiskolcMiskolc-Egyetemváros H-3515Hungary

We consider the class of parametric curves that can be represented by combination of control points and basis func- tions. A control point is let vary while the rest is held fixed. It’s shown that the locus of the moving control point that yields points of zero torsion is the osculating plane of the corresponding discriminant curve at its point of the same parameter value. The special case is studied when the basis functions sum to one.

关键词： Parametric curve Torsion Discriminant curve

Role of Dilatometrical measurements in the Development of multiphase Steels

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材料热处理学报 2004年第5期25卷 41-44页

作者： mártonTakács BalázsVeroe ImreFelde JianshengPan BayZoltánInstituteofmaterialsScienceandTechnology BudapestHungary SchoolofmaterialsScienceandEngineeringShanghaiJiaoTongUniversity ShanghaiChina

Possibilities of means of dilatometry in connection with production of multiphase (DP- and TRIP-) steels were examined in detail. These steels are characterized by an excellent combination of high strength and good press formability, which are essentially important in the automotive industry. Transformation processes, cooling rates, holding temperatures, composition and technological parameters play a very important role in formation of applicable microstructure of multiphase steels. Dilatometrical experiments were carried out to study the processes of intercritical annealing and hot rolling of several DP- and TRIP-steels.

关键词：膨胀测定法多相钢相位变换模锻性

Improving ecosystem services in farmlands:beginning of a long-term ecological study with restored flower-rich grasslands

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Ecosystem Health and Sustainability 2022年第1期8卷 399-405页

作者： András Báldi Raoul Pellaton Áron Domonkos Bihaly Viktor szigeti Eszter Lellei-Kovács András máté miklós Sárospataki Zoltán Soltész LászlóSomay AnikóKovács-Hostyánszki Lendület Ecosystem Services Research Group Institute of Ecology and BotanyCentre for Ecological ResearchVácrátótHungary Department of Zoology and Ecology Institute of Wildlife Management and Nature ConservationHungarian University of Agriculture and Life SciencesGödöllőHungary Dorcadion Ltd KecskemétHungary

Biodiversity declines in an unprecedented way,mostly due to land use *** interventions proved to be one of the most effective tools to halt the decline,especially in ecosystems such as agricultural ***-based,locally adapted recommendations on grassland restoration,however,are often missing,so we present a novel approach for such interventions that can be implemented anywhere and that are based on scientific *** a recently started long-term field ecological study,we established 0.5 ha wildflower parcels,using a diverse local seed mixture of 32 insect-visited plant species in Central European agricultural landscapes in *** focus is on the landscape-scale effects of this ecological intensification on ecosystem services such as crop yield,pollination and pest control,and the long-term monitoring of the successional *** aim is to showcase an effective restoration protocol that could serve as a model for future farm management,and provide much-needed evidence for policy on landscape ecological restoration of international relevance.

关键词： Ecological intensification field experiment protocol restoration wildflower strip

Bone disorders in experimentally induced liver disease in growing rats

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World Journal of Gastroenterology 2005年第45期11卷 7169-7173页

作者： Viktória Ferencz csaba Horváth Béla Kári János Gaál szilvia mészáros Zsuzsanna Wolf Dalma Heged(?)s Andrea Horváth Anikó Folhoffer Ferenc szalay 1st Department of Internal medicine Department of Diagnostic Radiology and Oncotherapy Department of Polymer Engineering and Textile Technology

AIm： To investigate the change of bone parameters in a new model of experimentally induced liver cirrhosis and hepatocellular carcinoma （HCC） in growing rats. mETHODS： Fischer-344 rats （n = 55） were used. Carbon tetrachloride （CCh）, phenobarbital （PB）, and a single diethylnitrosamine （DEN） injection were used. Animals were killed at wk 8 and 16. Bone mineral content, femoral length, cortical index （quotient of cortical thickness and whole diameter） and ultimate bending load （Fmax） of the femora were determined. The results in animals treated with DEN＋PB＋CCh （DPC, n = 21） were com- pared to those in untreated animals （UNT, n = 14） and in control group treated only with DEN＋PB （DP, n = 20）. RESULTS： Fatty liver and cirrhosis developed in each DPC-treated rat at wk 8 and HCC was presented at wk 16. No skeletal changes were found in this group at wk 8, but each parameter was lower （P〈0.05 for each） at wk 16 in comparison to the control group. Neither fatty liver nor cirrhosis was observed in DP-treated animals at any time point. Femoral length and Fmax values were higher （P〈0.05 for both） in DP-treated animals at wk 8 compared to the UNT controls. However, no difference was found at wk 16. CONCLUSION： Experimental liver cirrhosis and HCC are accompanied with inhibited skeletal growth, reduced bone mass, and decreased mechanical resistance in growing rats. Our results are in concordance withthe data of other studies using different animal models. A novel finding is the transiently accelerated skeletal growth and bone strength after a 8-wk long phenobarbital treatment following diethylnitrosamine injection.

关键词： Bone disorder Bone mineral content mechanical resistance Experimental liver cirrhosis Growingrat

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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The versatility of mesenchymal stem cells:From regenerative medicine to COVID,what is next?

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BIOCELL 2022年第4期46卷 913-922页

作者： THAÍS CASAGRANDE PAIm mÁRCIA rosÂNGELA WINK Laboratório de Biologia Celular Universidade Federal de Ciências da Saúde de Porto Alegre(UFCSPA)Porto Alegre90050-170Brazil

mesenchymal stem cells(mScs)play key roles in regenerative medicine by promoting tissue *** can be isolated from different adult tissues and they are able to differentiate into several *** to their antiinflammatory,angiogenic and immune-modulatory properties,mScs are suitable for tissue engineering applications and,when associated with biomaterials,their benefits can be ***,recently,mScs have been studied for new clinical applications,such as in the treatment of patients with *** regenerative potential has been attributed to their secretome,which comprises extracellular matrix,soluble proteins and several elements,including the release of extracellular *** though,in order to explore all their therapeutic potential,it is still necessary to advance in the investigation of their basic cell biology characteristics.

关键词： mesenchymal stem cells Regenerative medicine Secretome Biomaterials Extracellular vesicles

Prediction to the Efficiency of Soft Clay Sample Preparation with Vacuum Loading

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China Ocean Engineering 1998年第2期13卷 243-251页

作者： Yan, SW Fang, sz Tianjin Univ Dept Hydraul Engn Tianjin 300072 Peoples R China

Vacuum loading has been examined as a way of preparing uniformly consolidated soft clay samples. The facility and loading procedure are described in this paper. An analytical solution to the three dimensional consolidation equation is derived for estimating the degree of consolidation of the soil sample with vacuum loading. The given example shows that the predicted degree of consolidation of a soft clay bulk with vacuum loading is close to that measured in the consolidation process.

关键词： reconstituted clay vacuum loading sample preparation 3D consolidation analytical solution