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Advances in Pure Mathematics 2022年第9期12卷 505-518页

作者： vânia gonçalves de brito dos santos Paula Tamires Gomes dos Anjos departamento de Ciências Exatas e da Terra Universidade do Estado da Bahia (UNEB) Salvador Brazil Centro Educacional Expoente (CEdeX) Brasília Brazil

The solution of many conduction heat transfer problems is found by two-dimensional simplification using the analytical method since different points have different initial temperatures. The temperature at each point of a given element can be analyzed through the Heat Equation that, in some cases, converges to analytical solutions without precision and is far from the real. However, with the application of the Finite Difference Method (FDM), it is possible to solve it numerically in a relatively fast way, providing satisfactory results for the most varied boundary conditions and diverse geometries, characteristics of heat transfer problems by conduction. This study solved two problems inside a plate with and without heat generation involved in temperature distribution. Algorithms were built with the aid of the Matlab programming language, and applied to obtain a numerical solution using the FDM numerical method. The computational and analytical solutions were then compared. Under certain conditions of the parameters involved in the phenomenon of each problem, the numerical method was very efficient for presenting errors less than or equal to 0.003 and 0.03, respectively, for cases without and with heat generation.

关键词： Heat Transfer Conduction Finite Difference Method Numerical Method Matlab

Emerging role of liquid biopsy in rat sarcoma virus mutated metastatic colorectal cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 234-243页

作者： João Gramaça Isabel Gomes Fernandes Carolina Trabulo Joana gonçalves Rita Gameiro dos santos Adriano Baptista Idília Pina Centro Hospitalar Barreiro Montijo Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal Medical Oncology Unit Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal

BACKGROUND In patients with metastatic colorectal cancer(mCRC),the treatment options are limited and have been proved to be affected by rat sarcoma virus(RAS)mutational *** RAS wild-type(wt)patients,the combination of antiepidermal growth factor receptor(EGFR)monoclonal antibodies with chemotherapy(CT)is more effective than CT *** the other hand,RAS-mutated patients are not eligible for treatment with anti-EGFR *** SUMMARY Eleven patients with initially RAS-mutated mCRC were followed from diagnosis to May *** the time of cell-free DNA determination,five patients had undergone one CT line,five patients had undergone two CT lines,and one patient had undergone three CT lines(all in combination with bevacizumab).At the second and third treatment lines[second line(2L),third line(3L)],patients with neo-RAS wt received a combination of CT and *** neo-RAS wt patients treated with anti-EGFR,our findings indicated an increase in progression-free survival for both 2L and 3L(14.5 mo,P=0.119 and 3.9 mo,P=0.882,respectively).Regarding 2L overall survival,we registered a slight increase in neo-RAS wt patients treated with anti-EGFR(33.6 mo vs 32.4 mo,P=0.385).At data cut-off,two patients were still alive:A RAS-mutated patient undergoing 3L treatment and a neo-RAS wt patient who received 2L treatment with anti-EGFR(ongoing).CONCLUSION Our case series demonstrated that monitoring RAS mutations in mCRC by liquid biopsy may provide an additional treatment line for neo-RAS wt patients.

关键词： Metastatic colorectal cancer Rat sarcoma virus mutational status Liquid biopsy Rat sarcoma virus wild-type Neo-rat sarcoma virus wild-type Anti-epidermal growth factor receptor therapy Case report

ENSO impacts on litter stocks and water holding capacity in secondary forests in eastern Amazonia

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Journal of Forestry Research 2024年第1期35卷 83-89页

作者： Julia Isabella de Matos Rodrigues Walmer Bruno Rocha Martins victor Pereira de Oliveira Myriam Suelen da Silva Wanzerley Hélio brito dos santos Júnior Francisco de Assis Oliveira Graduate Program in Forestry Sciences Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Tv.Pau-AmareloCapitão PoçoPará68650-000Brazil National Institute of Amazonia Research Av.Constelação Cruzeiro do SulManausAmazonas 69060-062Brazil

Among the impacts of climate change,there is the intensification of phenomena such as the El Niño South-ern Oscillation(ENSO)responsible for El Niño and La Niñ***,understanding their effects on the functional pro-cesses of forests is ***,this study evaluated the effects of ENSO on litter stock and water holding capac-ity(WHC)in a successional forest in eastern *** occurred in periods with the most rainfall in El Niño(2019)and least in La Niña(2021)*** permanent plots were used to sample *** effects were evident for WHC,higher during El Niñ***,this influence was not clear for litter,as only in the rainy season effects were *** was a positive correlation of WHC with precipitation and humidity,while litter stocks were negatively correlated with temperature and wind *** the subject of this study requires long-term assessments,preliminary results suggests that,depending on the intensity of ENSO,forest functional processes can be strongly impacted and *** conclusion reinforces warnings by the scientific community about the impacts of climate change on the maintenance of litter stocks,decomposition and,consequently,the biogeochemical cycle and essential ecosystem services for the maintenance of Amazonia *** need to develop long-term research to understand the effects of climatic change on litter stocks and water holding capacity is highlighted,especially in Amazonia.

关键词： Seasonality Climate change Succession ecosystem Biogeochemical cycle Amazonia biodiversity

The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe Augusto de Paula Pacheco M.Magelli Matheus valente Lopes Pedro Henrique alves Correa N.Zampieri N.Bosso Auteliano Antunes dos santos Federal Institute of the Southeast of Minas Gerais(IF Sudeste MG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil department of Mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation

Capacitorless Solid-state Power Filter for Single-phase DC-AC Converters

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli C.dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

Converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(LC)cell or an inductor-capacitor-inductor(LCL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the LC filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) Capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

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Journal of Sport and Health Science 2024年第4期13卷 548-558,F0003页

作者： Hugo de Luca Correa Lysleine alves deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinesio Silva Neto Claudio Avelino Rodrigues santos Paolo Lucas Rodrigues-Silva Fernando Honorato Souza vitoria Marra da Motta vilalva Mestrinho Rafael Lavarini dos santos Rosangela vieira Andrade Jonato Prestes Thiago dos santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance Mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil department of Medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of Medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Background:Hemodialysis(HD) per se is a risk factor for *** the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training *** aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this ***:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of ded concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning ***:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD ***,RE+BFR significantly increases D-dimer after 4 *** with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

关键词： Blood-flow restriction Chronic kidney disease Coagulation Hemodialysis vascular occlusion exercises

Unveiling the silent crisis:global burden of suicide‑related deaths among children aged 10–14 years

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World Journal of Pediatrics 2024年第4期20卷 371-391页

作者： Irmina Maria Michalek Pawel Koczkodaj Marzena Michalek Florentino Luciano Caetano dos santos department of Cancer Epidemiology and Primary Prevention Maria Sklodowska-Curie National Research Institute of Oncologyul.Wawelska 15 BWarsawPoland Private Psychiatric Practice-Marzena Michalek MDSiedlcePoland Harvard Business School Harvard UniversityBostonMAUSA

Background The rise in suicides among children aged 10–14 years demands urgent attention *** study aims to assess the global burden of suicide-related deaths in this age group from 1990 to 2019,considering factors such as sex,geography,and sociodemographics,to inform prevention strategies and *** The data from Global Burden of Disease 2019,encompassing 204 countries and territories,were analyzed to investigate deaths and years of life lost(YLLs)due to suicide among children aged 10–14 *** analyses,including mortality rates,YLLs,and the sociodemographic index(SDI),were conducted using standardized *** In 2019,a total of 8327[95%uncertainty interval(UI)=7073–9685]children aged 10–14 years died globally due to suicide,with a mortality rate of 1.30(95%UI=1.10–1.51)per 100,*** rates varied across countries/territories ranging between 0.05(95%UI=0.02–0.10)in South Africa and 7.49(95%UI=5.13–10.57)in *** contribution of suicide-related deaths to all-cause mortality ranged from 0.07%(95%UI=0.04%–0.15%)in South Africa to 33.02%(95%UI=24.36%–41.53%)in ***,there were approximately 636,196(95%UI=540,383–740,009)YLLs due to suicide,with a rate of 99.07(95%UI=84.15–115.23)per 100,*** association between SDI and suicide-related deaths was evident,with higher contributions observed in countries with higher *** This study reveals a concerning global burden of suicide-related deaths among children aged 10–14 *** progress in reducing mortality rates,suicide remains a significant *** overall rates have declined,the percentage of deaths caused by suicide in this age group is increasing.

关键词： Early adolescent Global Burden of Disease Incidence Suicide Years of life lost

Elevation transition of aquatic insects closely matches a thermal feature in the Yungas of Northwestern Argentina

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Journal of Mountain Science 2024年第2期21卷 433-448页

作者： Alexandra BUITRAGO-GUACANAME Carlos MOLINERI Andrés LIRA-NORIEGA Daniel Andrés dos santos Neotropical Biodiversity Institute(CONICET-UNT) UNT-DomesHorco Molle S/N4107 TucumánArgentina CONACYT Research Fellow Network of Advanced Molecular StudiesInstitute of Ecology A.COld Road to Coatepec 351El HayaCP 91073XalapaVeracruzMexico Biostatistics Chair Faculty of Natural Sciences and IMLNational University of TucumánSan Miguel de TucumánMiguel Lillo 2054000 TucumánArgentina

Temperature is a key factor that shapes the distribution of *** knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate *** insects are particularly vulnerable to climate change,yet there is still much to learn about their ecology and *** the Yungas ecoregion of Northwestern Argentina,cold-and warm-adapted species of the orders Ephemeroptera,Plecoptera,and Trichoptera(EPT)are segregated by *** modeled the ecological niche of South American EPT species in this region using available data and projected their potential distribution in geographic *** were grouped based on their ecogeographic similarity,and we analyzed their replacement pattern along elevation gradients,focusing on the ecotone where opposing thermal preferences *** this interface,we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant transition *** found that the Montane Cloud Forest holds the interface,with a particularly greater suitability at its lower *** main axis of the interface runs in a N-S direction and falls between 14°C-16°C mean annual *** probability of a particular location within a basin being classified as part of the interface increases as Kira’s warmth index approaches a score around *** the interface is critical for defining the thermal limits of species distribution and designing biomonitoring *** in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation *** have recognized significant temperature thresholds that serve as indicators of suitability for the *** global warming is anticipated to shift these indicators,we suggest using them to monitor the imprints of climate change on mountain ecosystems.

关键词： Austral Yungas Ecological Niche Model Ephemeroptera Kira’s warmth index Plecoptera Trichoptera

New avenues for the treatment of immunotherapy-resistant pancreatic cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1134-1153页

作者： Luis Guilherme de Oliveira Silva Fabian Fellipe Bueno Lemos Marcel Silva Luz Samuel Luca Rocha Pinheiro Mariana dos santos Calmon Gabriel Lima Correa santos Gabriel Reis Rocha Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Pancreatic cancer(PC)is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases ***,due to its complexity,it ranks 7th in the list of the most lethal cancers *** pathogenesis of PC involves several complex processes,including familial genetic factors associated with risk factors such as obesity,diabetes mellitus,chronic pancreatitis,and *** in genes such as KRAS,TP53,and SMAD4 are linked to the appearance of malignant cells that generate pancreatic lesions and,consequently,*** this context,some therapies are used for PC,one of which is immunotherapy,which is extremely promising in various other types of cancer but has shown little response in the treatment of PC due to various resistance mechanisms that contribute to a drop in immunotherapy *** is therefore clear that the tumor microenvironment(TME)has a huge impact on the resistance process,since cellular and non-cellular elements create an immunosuppressive environment,characterized by a dense desmoplastic stroma with cancerassociated fibroblasts,pancreatic stellate cells,extracellular matrix,and immunosuppressive *** to this are genetic mutations in TP53 and immunosuppressive factors that act on T cells,resulting in a shortage of CD8+T cells and limited expression of activation markers such as *** this way,finding new strategies that make it possible to manipulate resistance mechanisms is ***,techniques such as the use of TME modulators that block receptors and stromal molecules that generate resistance,the use of genetic manipulation in specific regions,such as microRNAs,the modulation of extrinsic and intrinsic factors associated with T cells,and,above all,therapeutic models that combine these modulation techniques constitute the promising future of PC ***,this study aims to elucidate the main mechanisms of resistance to immunotherapy in PC and new ways of manipulating thi

关键词： Pancreatic cancer Immunotherapy Resistance Tumor microenvironment manipulation Combined immunotherapy

Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

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Journal of Forestry Research 2024年第2期35卷 209-221页

作者： Antônio Carlos vargas Motta Shizuo Maeda valdécio dos santos dos santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior Ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa João Bosco vasconcellos Gomes department of Soil Sciences and Agriculture Engineering Federal University of ParanáR.dos Funcionários1540.CuritibaParanáCEP 80035‑050Brazil Brazilian Agricultural Research Company Embrapa FlorestasEstr.da Ribeira–Br‑476Km 111–Parque Monte Castelo.ColomboParanáCEP 83411‑000Brazil United States department of Agriculture‑Agricultural Research Service USDA-ARS National Soil Dynamics Laboratory411 South Donahue DriveAuburnAL 36832USA Reforestation Remasa Rodovia PR 170–Km 522.BiturunaParanáCEP 84640‑000Brazil Federal Institute of Southeast of Minas Gerais R.Luz Interior360.Juiz de ForaMinas Gerais CEP 36030‑713Brazil

Needle chlorosis(NC)in Pinus taeda *** in Brazil becomes more frequent after second and third harvest rotation *** a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on *** were analyzed for various elements and *** soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple *** symptoms started at needle tips,then extended toward the needle base with *** flush needles had longer portions with YNC than second flush needles *** from the lower crown also had more symptoms along their length than those higher in the *** were similar to those reported for *** chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of *** in various parent soils in Brazil.

关键词： Nutritional deficiency Forest management Soil depletion Pine foliar analysis Needle chlorosis