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early Phases of Star Formation: Testing chemical Tools

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

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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 AliÖvgün 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

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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

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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

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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

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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 Fora Department of computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOc content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In 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 precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOc. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. core samples from the YuDong-nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOc. The 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 metrics. Such 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

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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

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Management of obstructed colorectal carcinoma in an emergency setting:An update

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 598-613页

作者： efstathios T Pavlidis Ioannis n Galanis Theodoros e Pavlidis 2nd Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

colorectal carcinoma is common,particularly on the left *** 20%of patients,obstruction and ileus may be the first clinical manifestations of a carcinoma that has advanced(stage II,III or even IV).Diagnosis is based on clinical presentation,plain abdominal radiogram,computed tomography(cT),cT colonography and positron emission tomography/*** best management strategy in terms of short-term operative or interventional and long-term oncological outcomes re-mains *** the most common left-sided obstruction,the first choice should be either emergency surgery or endoscopic decompression by self-expen-dable metal stents or *** operative plan should be either one-stage or two-stage ***-stage resection with on-table bowel decompression and irrigation can be accompanied or not accompanied by proximal defunctioning stoma(colostomy or ileostomy).Primary anastomosis is more convenient but has increased risks of anastomotic leakage and ***-stage resection(Hart-mann’s procedure)is safer and the most widely used despite temporally affecting quality of *** control surgery in high-risk frail patients is less frequently performed since it can be successfully substituted with endoscopic stenting or *** the less common right-sided obstruction,one-stage surgical resection is more beneficial than endoscopic *** role of minimally invasive surgery(laparoscopic or robotic)is a subject of *** laparoscopic-assisted management is advantageous to some extent but requires much expertise due to inherent difficulties in dissecting the distended colon and the risk of rup-ture and subsequent septic *** decompressing stent as a bridge to elective surgery more substantially decreases the risks of morbidity and mortality than emergency surgery for decompression and has equivalent medium-term overall survival and disease-free survival *** combination with neoadjuvant chemotherapy or radiation may have a p

关键词： Acute abdomen Obstructive ileus colorectal carcinoma emergency surgery colectomy Intraluminal metal stents

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current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct

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World Journal of Gastroenterology 2024年第10期30卷 1461-1465页

作者： efstathios T Pavlidis Ioannis n Galanis Theodoros e Pavlidis 2^(nd) Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Pancreatobiliary intraductal papillary neoplasms(IPns)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and *** advances in diagnostic methods,identifying these premalignant lesions is still challenging for treatment *** imaging,biomarkers and molecular tests for genomic alterations can be used for diagnosis and *** intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant *** balance between the risk of malignancy and any risk of resection guides management policy;therefore,treatment should be individualized based on a meticulous preoperative assessment of high-risk *** of the bile duct is more aggressive;thus,early diagnosis and surgery are *** conservative management of low-risk pancreatic branch-duct lesions is safe and effective.

关键词： Biliary tree diseases Pancreatic cystic neoplasms Biliary tract neoplasms extrahepatic cholangiocarcinoma Pancreatic adenocarcinoma

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current considerations for the surgical management of gallbladder adenomas

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1507-1512页

作者： efstathios T Pavlidis Ioannis n Galanis Theodoros e Pavlidis The Second Department of Propaedeutic Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder adenomas are rare lesions(0.5%)associated with potential malignant transformation,particularly with gallbladder adenomas that are≥1 cm in *** detection and management are crucial for preventing lethal carcinoma *** polyps can often be distinguished from the more often nonneo-plastic cholesterol pseudopolyps(5%-10%),which are *** is the first-line tool for initial diagnosis and follow-up when *** question is whether cholecystectomy is always necessary for all *** manage-ment of gallbladder adenomas is determined according to the size of the tumor,the growth rate of the tumor,the patient’s symptoms and whether risk factors for malignancy are ***≥1 cm in size,an age>50 years and a familial history of gallbladder carcinoma are indications for immediate laparoscopic ***,ultrasound follow-up is *** adenomas 6-9 mm in size,the absence of≥2 mm growth at 6 months,one year,and two years,as well as an adenoma sizedexisting risk factors indicates that no further surveillance is ***,it would be preferable to individualize the management in doubtful *** interventional modalities for preserving the gallbladder need further evaluation,especially to determine the long-term outcomes.

关键词： Biliary diseases True neoplastic polyps Gallbladder adenomas Benign bi-liary tumors Gallbladder polyps extrahepatic biliary neoplasms

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