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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

Chromomagnetic dipole moments of light quarks in the bestest little Higgs model

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Chinese Physics C 2024年第10期48卷 125-136页

作者： T.Cisneros-Pérez e.Cruz-Albaro A.Y.Ojeda-Castañeda s.e.solís-núñez Unidad Académica de Ciencias Químicas Universidad Autónoma de ZacatecasApartado Postal C-58598060 ZacatecasMexico Facultad de Física Universidad Autónoma de ZacatecasApartado Postal C-58098060 ZacatecasMexico

In this study,we investigated the anomalous Chromomagnetic Dipole Moment(CMDM),denoted as μ_(q)^(BLHM),of light quarks q=(u,c,d,s,b) within the framework of the Bestest Little Higgs Model(BLHM)as an extension of the standard Model(sM).Our investigation encompassed novel interactions among the light quarks,heavy quark B,and heavy bosons (W'^(±),H^(±),φ^(±),η^(±))incorporating the extended Cabibbo-Kobayashi-Maskawa(CKM)matrix characteristic of the *** thoroughly explored the permissible parameter space,yielding a spectrum of CMDM values ranging from 10^(-10) to 10^(-3).

关键词： beyond standard model flavor physics chromomagnetic dipole light quarks

Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean energy 2024年第1期8卷 188-196页

作者： Basem e.elnagi Ahmed M.Ismaiel Hany s.e.Mansour M.n.Abd-Alwahab electrical engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a MATLAB®/simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： PeM fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

Ca-based materials derived from calcined cigarette butts for CO_(2)capture and thermochemical energy storage

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Journal of environmental sciences 2024年第6期140卷 230-241页

作者： nabil Amghar Virginia Moreno Pedro e.sánchez-Jiménez Antonio Perejón Luis A.Pérez-Maqueda Instituto de Ciencia de Materiales de sevilla C.S.I.C.-Universidad de SevillaC.Américo Vespucio4941092 SevillaSpain Instituto de Tecnología de Materiales(ITM) Universitat Politècnica de València(UPV)Plaza Ferrándiz y Carbonell 1AlcoyAlicante 03801Spain Departamento de Química Inorgánica Facultad de QuímicaUniversidad de Sevilla41012 SevillaSpain

Cigarette butts(CBs)are one of the most common types of litter in the *** to the toxic substances they contain,the waste generated poses a harmful risk to the environment,and therefore there is an urgent need for alternative solutions to landfill ***,this work presents a possible revalorization of this waste material,which implies interesting environmental *** were used as sacrificial templates for the preparation of CaO-based materials by impregnation with calcium and magnesium nitrates followed by flaming *** materials presented enhanced porosity for their use in the Calcium Looping process applied either to thermochemical energy storage or CO_(2)capture *** influence of the concentration of Ca and Mg in the impregnating solutions on the multicycle reactivity of the samples was *** improved multicycle performance was obtained in terms of conversion for both applications.

关键词： Cigarette butts Calcium-Looping CO_(2)Capture Thermochemical energy storage

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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

Role of climatic variability in shaping intraspecific variation of thermal tolerance in Mediterranean water beetles

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Insect science 2024年第1期31卷 285-298页

作者： susana Pallarés David Garoffolo Belén Rodríguez David sánchez-Fernández Department of Zoology University of SevilleSevilleSpain Faculty of Biology Department of Ecology and HydrologyUniversity of MurciaCampus EspinardoMurciaSpain

The climatic variability hypothesis(CVH)predicts that organisms in more thermally variable environments have wider thermal breadths and higher thermal plasticity than those from more stable ***,due to evolutionary trade-offs,taxa with greater absolute thermal limits may have little plasticity of such limits(trade-off hypothesis).The CVH assumes that climatic variability is the ultimate driver of thermal tolerance variation across latitudinal and altitudinal gradients,but average temperature also varies along such *** explored intraspecific variation of thermal tolerance in three typical Mediterranean saline water beetles(families Hydrophilidae and Dytiscidae).For each species,we compared two populations where the species coexist,with similar annual mean temperature but contrasting thermal variability(continental *** population).We estimated thermal limits of adults from each population,previously acclimated at 17,20,or 25℃.We found species-specific patterns but overall,our results agree with the CVH regarding thermal ranges,which were wider in the continental(more variable)*** the two hydrophilid species,this came at the cost of losing plasticity of the upper thermal limit in this population,supporting the trade-off hypothesis,but not in the dytiscid *** results support the role of local adaptation to thermal variability and trade-offs between basal tolerance and physiological plasticity in shaping thermal tolerance in aquatic ectotherms,but also suggest that intraspecific variation of thermal tolerance does not fit a general pattern among aquatic *** such intraspecific variation could lead to inaccurate predictions of the vulnerability of aquatic insects to global warming.

关键词： acclimation capacity aquatic insects climate change heat coma temperature supercooling point thermal plasticity

Unravelling COVID-19 waves in Rio de Janeiro city:Qualitative insights from nonlinear dynamic analysis

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Infectious Disease Modelling 2024年第2期9卷 314-328页

作者： Adriane s.Reis Laurita dos santos Américo Cunha Jr Thaís C.R.O.Konstantyner elbert e.n.Macao Institute of science and Technology Federal University of São PauloSão Josédos CamposSPBrazil Physics Institute University of São PauloSão PauloSPBrazil scientific and Technological Institute Universidade BrasilSão PauloSPBrazil Department of Applied Mathematics Rio de Janeiro State UniversityRio de JaneiroRJBrazil Paulista school of Medicine Federal University of São PauloSão PauloSPBrazil

since the COVID-19 pandemic was first reported in 2019,it has rapidly spread around the *** countries implemented several measures to try to control the virus *** healthcare system and consequently the general quality of life population in the cities have all been significantly impacted by the Coronavirus *** different waves of contagious were responsible for the increase in the number of cases that,unfortunately,many times lead to *** this paper,we aim to characterize the dynamics of the six waves of cases and deaths caused by COVID-19 in Rio de Janeiro city using techniques such as the Poincaréplot,approximate entropy,second-order difference plot,and central tendency *** results reveal that by examining the structure and patterns of the time series,using a set of non-linear techniques we can gain a better understanding of the role of multiple waves of COVID-19,also,we can identify underlying dynamics of disease spreading and extract meaningful information about the dynamical behavior of epidemiological time *** findings can help to closely approximate the dynamics of virus spread and obtain a correlation between the different stages of the disease,allowing us to identify and categorize the stages due to different virus variants that are reflected in the time series.

关键词： COVID-19 nonlinear analysis Poincaréplot Central tendency measure

Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central spain)

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Avian Research 2024年第2期15卷 180-186页

作者： Carlos Lazaro Carlos sanchez-García Fabian Casas e.Jorge Tizado Department of Research Fundacion Artemisan13001 Ciudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain Department of Biodiversity and environmental Management Universidad de Leon24401 PonferradaSpain

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their *** January 2021,a strong snowstorm known as‘Filomena’affected spain,mainly the region of Madrid(Central spain),which was fully covered with snow and suffered freezing temperatures for a *** bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).no significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by *** suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home *** results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

关键词： Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica Winter

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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