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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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Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIn M.R.nURGALIEV A.R.nEMETS I.A.ZEMTSOV S.D.SUnTSOV T.B.MYALTOn D.S.SERGEEV n.A.SOLOVEV D.V.SARYCHEV D.V.RYJAKOV S.n.TUGARInOV n.n.nAUMEnKO national Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. Discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

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Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： nora Agh Henriett Anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(ng did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences

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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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Thoracoscopy in Cameroon: Indications, Technics and Short Term Results

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Surgical Science 2024年第4期15卷 278-288页

作者： Guy Aristide Bang Richard ii Mbele Fabrice Stephane Arroye Betou Arlette Joelle Moukitek Banaken Amos Bella Ela Charles Mve Mvondo Arthur Essomba Department of Surgery and Specialities Faculty of Medicine and Biomedical Sciences Yaound&#233 I University Yaound&#233 Cameroon Department of Surgery and Specialities Yaound&#233 Teaching Hospital Yaound&#233 Cameroon General Surgery Service Mvog-Ada District Hospital Yaound&#233 Cameroon Department of Cardiothoracic and Vascular Surgery Laquintinie Hospital Douala Cameroon Department of Cardiothoracic and Vascular Surgery Yaound&#233 General Hospital Yaound&#233 Cameroon Cardiac Center Shisong St. Elizabeth Catholic General Hospital Shisong Kumbo Cameroon

Introduction: Thoracoscopy is a video-assisted surgical approach that mirrors the techniques used in thoracotomy. Our aim is to map the current state of thoracoscopy practice in Cameroon’s hospitals. Methods: This was a descriptive study that collected both retrospective and prospective data over 57 months across four hospitals in Cameroon. It included 13 patients and focused on variables such as socio-demographic factors, clinical profiles, surgical procedures, and postoperative follow-up. Results: Thirteen patients, predominantly male (84.6%, n = 11), with a mean age of 37.5 ± 16 years, were enrolled. Alcohol use (61.5%) and smoking (38.5%) were the most common past histories. The major complaints were dyspnea (84.6%) and chest pain (58.3%). The primary surgical procedure was clot-free thoracoscopy in 30.8% of cases, mainly for persistent hemothorax (41.8%). Most surgeries were elective (76.9%) and performed under general anesthesia with selective intubation (61.5%). The most common approach was single-port thoracoscopy (U-VATS) (76.9%), with no reported difficulties;however, one intraoperative incident occurred and was successfully treated. Drainage was performed systematically in all patients, and one case required conversion to open surgery. Postoperative complications were minor (Clavien-Dindo grade I) and mainly consisted of pain, with a mortality rate of 15.4%. no significant association was found between risk factors and the occurrence of complications or postoperative mortality. Conclusion: Thoracoscopy, a novel approach in our context, primarily focuses on minor thoracic surgeries.

关键词： Thoracoscopy Single-Port Hemothorax Cameroon

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Glacier area change (1993-2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India

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Journal of Mountain Science 2024年第4期21卷 1287-1306页

作者： VATSAL Sarvagya AZAM Mohd Farooq BHARDWAJ Anshuman MAnDAL Arindan BAHUGUnA Ishmohan RAMAnATHAn Alagappan RAJU n.Janardhana TOMAR Sangita Singh Department of Civil Engineering Indian Institute of Technology IndoreSimrol 453552India School of Geosciences University of AberdeenKing’s CollegeAberdeen AB243FXUnited Kingdom Interdisciplinary Centre for Water Research Indian Institute of ScienceBengaluru 560012India Space Application Centre Ahmedabad 380015India School of Environmental Sciences Jawaharlal Nehru UniversityNew Delhi 110067India Department of Geography Norwegian University of Science and TechnologyTrondheim No-7491Norway

Glacier inventories serve as critical baseline data for understanding the impacts of climate change on *** present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered *** changes are estimated for three periods:1993-2000,2000-2010,and *** total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in *** mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and *** is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during *** field surveys on Chhota Shigri,Panchi ii,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite *** of various morphological parameters on retreat were also *** is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin.

关键词： Glacier Area change Debris cover Morphology Proglacial lake

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Life Origin in the Milky Way Galaxy: ii. Scanning for Habitable Stellar Systems on Behalf of Future Space Missions

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 681-692页

作者： Alexander n. Safronov Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow Russia

The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), n (nitrogen), and P (phosphorus) are found, are called DnA-stars. Based on stellar abundances a new method for searching for habitable exoplanets has been developed and a list of 48 DnA-stars in the solar neighborhood, on which life is possible, has been defined. The quota of DnA-stars is equal 1.3% of the total amount of Hypatia Stellar Catalog. Only three DnA-stars out of selected 48 stars belong to the spectral class as our Sun (G2V). The closest to the solar system is the DnA-star with the number HIP 15510, which belongs to the G8V class and is 6 pc away from the solar system. nine DnA-stars, which have the highest chemical similarity with solar spectrum, were identified. It is identified that one of these nine stars, HIP 24681, has six planets.

关键词： Interstellar Mission Stellar Abundance Habitability Hypatia Stellar Catalog DnA-Star

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Sodium-glucose cotransporter-2 inhibitors protect tissues via cellular and mitochondrial pathways:Experimental and clinical evidence

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World Journal of Experimental Medicine 2024年第2期14卷 46-52页

作者： Raúl Lelio Sanz Sebastián García Menéndez Felipe Inserra Leon Ferder Walter Manucha Department of Pathology Facultad de Ciencias MédicasUniversidad Nacional de CuyoMendoza 5500Argentina Department of Pharmacology Instituto de Medicina y Biología Experimental de CuyoCentro Científico TecnológicoMendoza 5500Argentina Department of nephrology Universidad de MaimónidesCiudad Autónoma de Buenos Aires C1405Argentina Department of Cardiology Universidad de MaimónidesCiudad Autónoma de Buenos Aires C1405Argentina

Mitochondrial dysfunction is a key driver of cardiovascular disease(CVD)in metabolic syndrome and *** dysfunction promotes the production of reactive oxygen species(ROS),which cause oxidative stress and *** ii,the main mediator of the renin-angiotensin-aldosterone system,also contributes to CVD by promoting ROS *** activity of sirtuins(SIRTs),a family of proteins that regulate cellular metabolism,also worsens oxidative *** of energy production by mitochondria is a common feature of all metabolic *** SIRT levels and 5’adenosine monophosphate-activated protein kinase signaling stimulate hypoxia-inducible factor 1 beta,which promotes ***,in turn,increases autophagy and mitophagy,processes that clear cells of debris and protect against *** cotransporter-2 inhibitors(SGLT2i),a class of drugs used to treat type 2 diabetes,have a beneficial effect on these *** clinical trials have shown that SGLT2i improves cardiac function and reduces the rate of cardiovascular and renal ***2i also increase mitochondrial efficiency,reduce oxidative stress and inflammation,and strengthen *** findings suggest that SGLT2i hold great potential for the treatment of ***,they are proposed as anti-aging drugs;however,rigorous research is needed to validate these preliminary findings.

关键词： Sodium-glucose cotransporter-2 inhibitors Cardiovascular diseases Sirtuins Oxidative stress Inflammation Mitochondrial dysfunction

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Enhanced termination of zinc and cadmium ions from wastewater employing plain and chitosan-modified mxenes: synthesis, characterization,and adsorption performance

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Green Chemical Engineering 2024年第03期5卷 339-347页

作者： njood R.Azeez Suhaib S.Salih Mohammed Kadhom Harith n.Mohammed Tushar K.Ghosh Department of Chemical Engineering College of Engineering University of Tikrit Department of Environmental Science College of Energy and Environmental Science Al-Karkh University of Science Department of nuclear Science & Engineering Institute University of Missouri-Columbia

Zinc and cadmium pollutants cause a significant environmental effect that cannot be ignored. Due to their considerable amount in an aqueous environment, industries are seeking suitable adsorbents that are environmentally friendly and inexpensive for removing metals from wastewater before disposing of them in surface waters. This research employed original MXene(MX) and chitosan-modified MXene(CSMX) to extract zinc(Zn(Ⅱ)) and cadmium(Cd(Ⅱ)) metal ions from water-based solutions. The composite material produced was analyzed using techniques such as X-ray Diffraction(XRD), Scanning Electron Microscopy(SEM), Fourier Transform Infrared Spectroscopy(FTIR), and Brunauer-Emmett-Teller(BET). The effects of contact duration, p H of the solution, and initial concentration of metal ions on the adsorption process of Zn(Ⅱ) and Cd(Ⅱ) onto both MX and CSMX composites were investigated. MX and prepared CSMX composite presented a high adsorption capacity for both studied heavy metals, which were 91.55 and 73.82 mg/g for Zn(Ⅱ) and Cd(Ⅱ) onto MX, 106.84 and 93.07 mg/g for Cd(Ⅱ) and Zn(Ⅱ) onto CSMX composite, respectively. Furthermore, the maximum competitive adsorption capacities for Zn(Ⅱ) onto MX and CSMX composites are 77.29 and 93.47 mg/g, and for are Cd(Ⅱ)60.30 and 79.66 mg/g, respectively. Hence, the removal capacities for both single and competitive metal ions were superior to CSMX composite. However, the adsorption capacities after five successive regeneration sequences were only dropped by 13.2% for Zn(Ⅱ) and 17.4% for Cd(Ⅱ) onto the CSMX composite compared to the first cycle. These results confirm that both metals could be efficiently terminated from wastewater, which makes the prepared CSMX composite a favorable candidate adsorbent in practical applications.

关键词： Adsorption Chitosan MXene Zn(ii) Cd(ii) Wastewater

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A Tutorial on Federated Learning from Theory to Practice:Foundations,Software Frameworks,Exemplary Use Cases,and Selected Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 824-850页

作者： M.Victoria Luzón nuria Rodríguez-Barroso Alberto Argente-Garrido Daniel Jiménez-López Jose M.Moyano Javier Del Ser Weiping Ding Francisco Herrera Department of Software Engineering Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Department of Computer Science and Artificial Intelligence Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Department of Communications Engineering University of the Basque Country(UPV/EHU)and also with TECNALIABasque Research&Technology Alliance(BRTA)Spain School of Information Science and Technology Nantong UniversityNantong 226019China

When data privacy is imposed as a necessity,Federated learning(FL)emerges as a relevant artificial intelligence field for developing machine learning(ML)models in a distributed and decentralized *** allows ML models to be trained on local devices without any need for centralized data transfer,thereby reducing both the exposure of sensitive data and the possibility of data interception by malicious third *** paradigm has gained momentum in the last few years,spurred by the plethora of real-world applications that have leveraged its ability to improve the efficiency of distributed learning and to accommodate numerous participants with their data *** virtue of FL,models can be learned from all such distributed data sources while preserving data *** aim of this paper is to provide a practical tutorial on FL,including a short methodology and a systematic analysis of existing software ***,our tutorial provides exemplary cases of study from three complementary perspectives:i)Foundations of FL,describing the main components of FL,from key elements to FL categories;ii)Implementation guidelines and exemplary cases of study,by systematically examining the functionalities provided by existing software frameworks for FL deployment,devising a methodology to design a FL scenario,and providing exemplary cases of study with source code for different ML approaches;and iii)Trends,shortly reviewing a non-exhaustive list of research directions that are under active investigation in the current FL *** ultimate purpose of this work is to establish itself as a referential work for researchers,developers,and data scientists willing to explore the capabilities of FL in practical applications.

关键词： Data privacy distributed machine learning federated learning software frameworks

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