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early Phases of Star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.Martinez S.Paron cOnIceT-Universidad de Buenos Aires.Instituto de Astronomía y Física del espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the Hcn/Hnc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II *** found that the use of the Hcn/Hnc ratio as a universal thermometer in the ISM should be taken with care because the Hcn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the Hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and *** molecular line widths of these four species increase from the IRDc to the HMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISM:molecules ISM:clouds

Imprints of a gravitational wave through the weak field deflection of photons

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chinese Physics c 2024年第8期48卷 240-245页

作者： Reggie c.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological contribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle can be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(Legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SAnRI KARAPInAR Zehra n.KUTLU İsmail e.KILIÇ Department of civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

In vivo astrocyte reprogramming following spinal cord injury

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neural Regeneration Research 2024年第3期19卷 487-488页

作者： Yannick n.Gerber Florence e.Perrin MMDn University of MontpellierEPHEINSERMMontpellierFrance Institut Universitaire de France(IUF) ParisFrance

Harmful and helpful roles of astrocytes in spinal cord injury(ScI):ScI induce gradable sensory,motor and autonomic impairments that correlate with the lesion severity and the rostro-caudal location of the injury *** absence of spontaneous axonal regeneration after injury results from neuron-intrinsic and neuron-extrinsic ***,not only adult neurons display limited capability to regrow axons but also the injury environment contains inhibitors to axonal regeneration and a lack of growth-promoting *** other cell populations that respond to the lesion,reactive astrocytes were first considered as only detrimental to spontaneous axonal ***,astrocytes.

关键词： injury impairment programming

nanomotion of bacteria to determine metabolic profile

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nanotechnology and Precision engineering 2024年第1期7卷 1-9页

作者： S.n.Pleskova e.V.Lazarenko n.A.Bezrukov R.n.Kriukov A.V.Boryakov M.e.Dokukin S.I.Surodin Research Laboratory of Scanning Probe Microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia Sarov Physics and Technology Institute National Research Nuclear University MEPhISarov 607186Russia

In addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection *** results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： nanomotion Bacteria cantilever Oscillation Atomic force microscopy Metabolism

Landau quantization effects on damping Kawahara solitons in electron–positron–ion plasma in rotating ionized medium

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communications in Theoretical Physics 2024年第10期76卷 143-152页

作者： e I el-Awady S Hussain n Akhtar Department of Physics Faculty of Science Port Said University Theoretical Physics Division (TPD) PINSTECH

For the dynamics of three-dimensional electron–positron–ion plasmas, a fluid quantum hydrodynamic model is proposed by considering Landau quantization effects in dense ***–neutral collisions in the presence of the coriolis force are also considered. The application of the reductive perturbation technique produces a wave evolution equation represented by a damped Korteweg–de Vries equation. This equation, however, is insufficient for describing waves in our system at very low dispersion coefficients. As a result, we considered the highest-order perturbation, which resulted in the damped Kawahara equation. The effects of the magnetic field, Landau quantization, the ratio of positron density to electron density, the ratio of positron density to ion density, and the direction cosine on linear dispersion laws as well as soliton and conoidal solutions of the damped Kawahara equation are explored. The understanding from this research can contribute to the broader field of astrophysics and aid in the interpretation of observational data from white dwarfs.

关键词： coriolis force Kawahara equation Landau quantization magnetoplasmas quantum plasma solitary and cnoidal waves

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.M.Saporetti L.c.Oliveira e.Pereira Department of computational and Applied Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOc content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology

RBc aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov P.B.ermolinskiy O.n.Scheglovitova n.n.Sklyankina A.V.Muravyov A.e.Lugovtsov A.V.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia n.F.Gamaleya national Research center for epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBcs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBc properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(nO),which is mainly produced by endothelial cells(ec)from L-arginine amino acid in the circulatory *** the mechanisms of the RBc-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced nO on RBc aggregation and adhesion to endothelium;(2)the nO e®ect on RBc aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBc aggregation and adhesion to a monolayer of ec were studied using optical tweezers(OT).The RBc deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that nO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only nO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBc aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of nO production by ***,data related to L-arginine accumulation by endothelium were obtained:necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,nO decreased the RBc-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBc adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

new trends in diagnosis and management of gallbladder carcinoma

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 13-29页

作者： efstathios T Pavlidis Ioannis n Galanis Theodoros e Pavlidis ^(nd)Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder(GB)carcinoma,although relatively rare,is the most common biliary tree cholangiocarcinoma with aggressiveness and poor *** is closely associated with cholelithiasis and long-standing large(>3 cm)gallstones in up to 90%of *** other main predisposing factors for GB carcinoma include molecular factors such as mutated genes,GB wall calcification(porcelain)or mainly mucosal microcalcifications,and GB polyps≥1 cm in *** is made by ultrasound,computed tomography(cT),and,more precisely,magnetic resonance imaging(MRI).Preoperative staging is of great importance in decisionmaking regarding therapeutic *** staging is based on MRI findings,the leading technique for liver metastasis imaging,enhanced three-phase cT angiography,or magnetic resonance angiography for major vessel *** is also necessary to use positron emission tomography(PeT)-cT or ^(18)F-FDG PeT-MRI to more accurately detect metastases and any other occult deposits with active metabolic *** laparoscopy may detect dissemination not otherwise found in 20%-28.6%of *** treatment is needed,including surgical resection,targeted therapy by biological agents according to molecular testing gene mapping,chemotherapy,radiation therapy,and *** is of great importance to understand the updated guidelines and current treatment *** extent of surgical intervention depends on the disease stage,ranging from simple cholecystectomy(T1a)to extended resections and including extended cholecystectomy(T1b),with wide lymph node resection in every case or IV-V segmentectomy(T2),hepatic trisegmentectomy or major hepatectomy accompanied by hepaticojejunostomy Roux-Y,and adjacent organ resection if necessary(T3).Laparoscopic or robotic surgery shows fewer postoperative complications and equivalent oncological outcomes when compared to open surgery,but much attention must be paid to avoiding *** addition to surgery,novel targe

关键词： Biliary tract neoplasms extrahepatic cholangiocarcinoma Gallbladder carcinoma Gallbladder diseases Biliary tree diseases Gastrointestinal malignancies