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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： H.HoSSEINI o.BALILASHAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

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Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João B.Relvas Institute of Research and Innovation in Health(i3S)and Institute for Molecular and Cell Biology(IBMC) University of PortoPortoPortugal Department of Biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Three-dimensional Weyl topology in one-dimensional photonic structures

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Light(Science & Applications) 2022年第7期11卷 1337-1338页

作者： Kosmas L.Tsakmakidis Tomasz P.stefański Section of Condensed Matter Physics Department of PhysicsNational and Kapodistrian University of AthensPanepistimioupolisGR-15784 AthensGreece Faculty of Electronics Telecommunicationsand InformaticsGdansk University of Technology80-233 GdanskPoland

Topological features,in particular distinct band intersections known as nodal rings,usually requiring three-dimensional structures,have now been demonstrated experimentally in an elegantly simple one-dimensional photo... 详细信息

关键词： crystal. dimensional topology

Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms

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Neural Regeneration Research 2025年第7期20卷 1995-1996页

作者： Rita o.Teodoro Mafalda Ribeiro Ramos Lara Carvalho iNoVA4Health NOVA Medical School|Faculdade de Ciências MédicasNMS|FCMUniversidade Nova de LisboaLisboaPortugal

Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no ***-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these *** and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse *** the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called *** plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024).

关键词： plasticity structural mechanisms

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.o’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

on determining the weight of edges in map-representing graphs-applications of heuristic methods in planning escape routes

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 1027-1043页

作者： Marta Borowska-stefańska MichałKowalski Filip Turoboś Szymon Wiśniewski Institute of the Built Environment and Spatial Policy Faculty of Geographical SciencesUniversity of LodzŁódź90–137Poland Institute of Mathematics Lodz University of TechnologyŁódź90–924Poland

In the paper we discuss and compare two commonly used methods of finding the shortest paths in networks,namely Dijkstra’s and A**** compare their effectiveness in terms of traversing road network in circumstances that require swift decision making in the event of dynamically changing road conditions on the basis of studies conducted for evacuation *** build a proper model of such a network,a method of appropriate edge-weighting is introduced,based on empirical data collected by other ***,we use the basics of the theory of quasimetric spaces to introduce a heuristic to such graphs,which is easy to calculate *** heuristic we obtain is both admissible and consistent,which allows us to use it efficiently in A*search *** developed application can be used in studies into evacuation from hazardous *** this case,optimum calculative efficiency is achievable with a simultaneous reduction of calculation time(when compared to Dijkstra’s algorithm).our application can be applied during the first stage,i.e.,prior to the occurrence of a disaster,since this is an appropriate time for preparation by planning,drilling,early warning,and designating the rescue services that are to participate in the following stages.

关键词： A*algorithm Dijkstra Heuristic methods Mathematical modelling Quasimetric spaces Planning escape routes

Usefulness of LED lightings in cereal breeding on example of wheat,barley and oat seedlings

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 32-37页

作者： Piotr stefański Patrycja Siedlarz Przemysław Matysik Krystyna Rybka Plant Breeding Strzelce Ltd.Co. ul.Główna 2099-307 StrzelcePoland Plant Breeding and Acclimatization Institute-National Research Institute 05-870 RadzikówPoland

The LED lightings in horticulture are becoming prevalent,due to their physical properties allowing reduction of electricity consumption and on modulation of light spectrum and *** present,LED lightings are not widely used by cereal breeding companies despite the fact that use of greenhouses is very *** is why,the present experiment was run to show the evidence of LED lightings usefulness in a cereal crops breeding *** wheat(Triticum aestivum,L.),spring barley(Hordeum vulgare,L.)and oat(Avena sativa,L.),one cultivar of each species,were used for the 9 week trial conducted in a greenhouse with strictly controlled temperature(22℃)and humidity(80%).As a light source,4 LED illuminators along with a high-pressure sodium and xenon lamps and a natural sunlight in non-shadowed area of the same greenhouse were *** illuminators were characterized by relatively high ratio of blue/red radiation(0.6-1.3)to force the stem shortening,since cereal seedlings with such a growth habit are preferred in greenhouse cultivation of *** was evidenced,that LED illuminators provided light suitable for cereals growth in a greenhouse,however each species had slightly different optimal light *** wheat and barley the best impact on stem shortening and also on time to heading had a LED illuminator with high multi wave-blue radiation whereas on the leaves width the illuminator with lowest blue/red *** oat seedlings a light source with highest light intensity and highest blue/red ratio seemed to be the most *** much differences in seedlings growth and time to heading suggested that there is a chance for construction of one universal type of LED illuminator designed for greenhouse stages of cereal crops breeding.

关键词： greenhouse light emitting diodes cost-effectiveness Triticum aestivum Hordeum vulgare Avena sativa

Efficiency of LED lamps used in cereal crop breeding greenhouses

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International Journal of Agricultural and Biological Engineering 2022年第2期15卷 75-83页

作者： Piotr stefański Patrycja Siedlarz-Słowacka Przemysław Matysik Krystyna Rybka Plant Breeding Strzelce Ltd.Co. ul.Główna 2099-307 StrzelcePoland Plant Breeding and Acclimatization Institute-National Research Institute 05-870 RadzikówPoland

LED lamps,which are becoming prevalent in horticulture,are also being installed in greenhouses dedicated to cereal crop ***,the issue arises with the real efficiency of LED *** high-budget programs,the smaller breeding companies in Poland face problems concerning the plant growth under LED lamps and the real costs of their *** experiment was conducted to compare seven different LED lamps and a high-intensity discharge(HID)lamp with a high-pressure sodium lamp(HPS)used as a *** studies,two varieties of wheat,barley,and oat species were *** plants’growth rate was assessed based on elongation growth and earing ***’physiological conditions were evaluated using chlorophyll a(Chl a)fluorescence measured on dark-adapted *** light spectra and intensities of tested lamps in parallel with electricity consumption were also *** results showed that 1)LEDs’physical properties and luminaire construction influence the amount of electricity consumed;2)the cereal crop species differ in lighting *** less light-sensitive was oat opposite barley,with wheat of moderate sensitivity;3)LED-6 lamp(PlantaLux S.A,Lublin,Poland)based on white diodes enriched by blue ones was the most cost-efficient and most optimal for studied species.

关键词： greenhouse light-emitting diodes cost-effectiveness cereal Triticum aestivum Hordeum vulgare Avena sativa

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