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Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, Ecuador 1990-2008

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Journal of Forestry Research 2014年第2期25卷 301-309页

作者： santiago bonilla-bedoya Juan R.Molina José E.Macedo-Pezzopane Miguel A.Herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon Region （EAR）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the protected areas in EAR.

关键词： Ecuadorian Amazon systematic transitions fragmentation natural regeneration

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Experimental and numerical investigation to elucidate the fluid flow through packed beds with structured particle packings

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Particuology 2024年第6期89卷 218-237页

作者： Shirin Patil Christian Gorges Joel Lòpez bonilla Moritz Stelter Frank Beyrau Berend van Wachem Laboratory of Technical Thermodynamics Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany Chair of Mechanical Process Engineering Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The present paper presents an experimental and numerical investigation of the dispersion of the gaseous jet flow and co-flow for the simple unit cell(SUC)and body-centred cubic(BCC)configuration of particles in packed beds.The experimental setup is built in such a way that suitable and simplified boundary conditions are imposed for the corresponding numerical framework,so the simulations can be done under very similar conditions as the experiments.Accordingly,a porous plate is used for the co-flow to achieve the uniform velocity and the fully developed flow is ensured for the jet flow.The SUC and BCC particle beds consist of 3D-printed spheres,and the non-isotropy near the walls is mostly eliminated by placing half-spheres at the channel walls.The flow velocities are analysed directly at the exit of the particle bed for both beds over 36 pores for the SUC configuration and 60 pores for the BCC configuration,for particle Reynolds numbers of 200,300,and 400.Stereo particle image velocimetry is experimentally arranged in such a way that the velocities over the entire region at the exit of the packed bed are obtained instantaneously.The numerical method consists of a state-of-the-art immersed boundary method with adaptive mesh refinement.The paper presents the pore jet structure and velocity field exiting from each pore for the SUC and BCC packed particle beds.The numerical and experimental studies show a good agreement for the SUC configuration for all flow velocities.For the BCC configuration,some differences can be observed in the pore jet flow structure between the simulations and the experiments,but the general flow velocity distribution shows a good overall agreement.The axial velocity is generally higher for the pores located near the centre of the packed bed than for the pores near the wall.In addition,the axial velocities are observed to increase near the peripheral pores of the packed bed.This behaviour is predominant for the BCC configuration as compared to the SUC configuration.The velocities near the per

关键词： Uniform particle packing Packed bed reactor Stereo particle image velocimetry Immersed boundary method

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Environmental drivers of long-term variations in the abundance of the red hocicudo mouse (Oxymycterus rufus) in Pampas agroecosystems

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Integrative Zoology 2024年第1期19卷 37-51页

作者： Laura Mariel CALFAYAN Regino CAVIA Jimena FRASCHINA Juan santiago GUIDOBONO Irene Laura GOROSITO María BUSCH Laboratorio de Ecología de Poblaciones Departamento de EcologíaGenética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and Instituto de EcologíaGenética y Evolución de Buenos Aires(IEGEBA)Buenos AiresArgentina

During the 20th century,there has been an ongoing agricultural expansion and global warming,two of the main determinants influencing biodiversity changes in Argentina.The red hocicudo mouse(Oxymycterus rufus)inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina agroecosystems.This paper describes the long-term temporal changes in O.rufus abundance in Exaltación de la Cruz department,Buenos Aires province,Argentina,in relation to weatherfluctuations and landscape features,as well as analyzes the spatio-temporal structure of captures of animals.We used generalized liner models,semi-variograms,the Mantel test,and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and 2014.O.rufus showed an increase in abundance across the years of study,with its distribution depending on landscape features,such as habitat types and the distance tofloodplains.Capture rates showed a spatio-temporal aggregation,suggesting expansion from previously occupied sites.O.rufus was more abundant at lower minimum temperatures in summer,higher precipitation in spring and summer,and lower precip-itations in winter.Weather conditions affected O.rufus abundance,but there was local variation that differed from global patterns of climate change.

关键词： agroecosystems climate change linear habitats Oxymycterus rufus rodent

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Predictive modeling of critical temperatures in magnesium compounds using transfer learning

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Journal of Magnesium and Alloys 2024年第4期12卷 1540-1553页

作者： Surjeet Kumar Russlan Jaafreh Subhajit Dutta Jung Hyeon Yoo santiago Pereznieto Kotiba Hamad Dae Ho Yoon School of Advanced Materials Science&Engineering Sungkyunkwan University Suwon 16419Republic of Korea

This study presents a transfer learning approach for discovering potential Mg-based superconductors utilizing a comprehensive target dataset.Initially,a large source dataset(Bandgap dataset)comprising approximately∼75k compounds is utilized for pretraining,followed by fine-tuning with a smaller Critical Temperature(T_(c))dataset containing∼300 compounds.Comparatively,there is a significant improvement in the performance of the transfer learning model over the traditional deep learning(DL)model in predicting Tc.Subsequently,the transfer learning model is applied to predict the properties of approximately 150k compounds.Predictions are validated computationally using density functional theory(DFT)calculations based on lattice dynamics-related theory.Moreover,to demonstrate the extended predictive capability of the transfer learning model for new materials,a pool of virtual compounds derived from prototype crystal structures from the Materials Project(MP)database is generated.T_(c) predictions are obtained for∼3600 virtual compounds,which underwent screening for electroneutrality and thermodynamic stability.An Extra Trees-based model is trained to utilize E_(hull)values to obtain thermodynamically stable materials,employing a dataset containing Ehull values for approximately 150k materials for training.Materials with Ehull values exceeding 5 meV/atom were filtered out,resulting in a refined list of potential Mg-based superconductors.This study showcases the effectiveness of transfer learning in predicting superconducting properties and highlights its potential for accelerating the discovery of Mg-based materials in the field of superconductivity.

关键词： Superconductivity Critical temperature Transfer learning Crystal structure features Thermodynamic stability

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SARS-CoV-2 triggers Dickkopf-1(Dkk-1)modulation of T helper cells and lung pathology in mice

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Genes & Diseases 2024年第4期11卷 9-12页

作者： Yifan Wu Freedom M.Green Stephen A.Shaw Lauren J.bonilla Shannon E.Ronca Maria Elena Bottazzi Farrah Kheradmand Jill E.Weatherhead Department of Pathology&Immunology One Baylor PlazaHoustonTX 77030USA Department of Pediatrics One Baylor PlazaHoustonTX 77030USA Department of Medicine One Baylor PlazaHoustonTX 77030USA National School of Tropical Medicine One Baylor PlazaHoustonTX 77030USA Molecular Virology&Microbiology One Baylor PlazaHoustonTX77030USA Biologyof Inflammation Center Baylor College of MedicineOne BaylorPlazaHoustonTX77030USA Michael E.DeBakey VA Center for Translational Research on Inflammatory Diseases HoustonTX 77030USA

Severe acute respiratory syndrome coronavirus 2(SARSCov-2)is the etiologic agent of the coronavirus disease 19(COVID-19)pandemic.In viral infections like SARS-CoV-2,a robust anti-viral type 1 immune response,including upregulation of type 1 CD4+T helper cells(Th1),is required for effective viral clearance while minimizing end-organ pathology and collateral tissue damage.

关键词： pathology acute respiratory

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Pancreatic neuroendocrine tumors:Are tumors smaller than 2 cm truly indolent?

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1756-1762页

作者： Sergio Hoyos Pablo Posada-Moreno Natalia Guzman-Arango Romario Chanci-Drago Jaime Chavez Alvaro Andrés-Duarte santiago Salazar-Ochoa Hepatobilary and Liver Transplant Unit Hospital Pablo Tobon Uribe and Gastrohepathology Group Universidad de AntioquiaMedellin 050034AntioquiaColombia Department of General Surgery Universidad Pontificia BolivarianaMedellín 050034AntioquiaColombia

BACKGROUND Pancreatic neuroendocrine tumors(PNETs)are relatively rare but rank as the second most common pancreatic neoplasm.They can be functional,causing early metabolic disturbances due to hormone secretion,or non-functional and diagnosed later based on tumor size-related symptoms.Recent diagnoses of PNETs under 2 cm in size have sparked debates about their management;some practitioners advocate for surgical removal and others suggest observation due to the tumors’lower potential for malignancy.However,it is unclear whether managing these small tumors expectantly is truly safe.AIM To evaluate poor prognostic factors in PNETs based on tumor size(>2 cm or<2 cm)in surgically treated patients.METHODS This cohort study included 64 patients with PNETs who underwent surgical resection between 2006 and 2019 at a high-complexity reference hospital in Medellín,Colombia.To assess patient survival,quarterly follow-ups were conducted during the first year after surgery,followed by semi-annual con-sultations at the hospital's hepatobiliary surgery department.Qualitative variables were described using absolute and relative frequencies,and quantitative variables were expressed using measures of central tendency and their corresponding measures of dispersion.RESULTS The presence of lymph node involvement,neural involvement,and lymphovascular invasion were all associated with an increased risk of mortality,with hazard ratios of 5.68(95%CI:1.26–25.61,P=0.024),6.44(95%CI:1.43–28.93,P=0.015),and 24.87(95%CI:2.98–207.19,P=0.003),respectively.Neural involvement and lymphovascular invasion were present in tumors smaller than 2 cm in diameter and those larger than 2 cm in diameter.The recurrence rates between the two tumor groups were furthermore similar:18.2%for tumors smaller than 2 cm and 21.4%for tumors larger than 2 cm.Patient survival was additionally comparable between the two tumor groups.CONCLUSION Tumor size does not dictate prognosis;lymph node and lymphovascular involvement affect mortality,which high-lights that histopath

关键词： Neuroendocrine tumor Pancreatic neoplasm Pancreas Pancreatic neuroendocrine neoplasm Pancreatic neuroendocrine tumors

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Selenium Differentially Regulates Flavonoid Accumulation and Antioxidant Capacities in Sprouts of Twenty Diverse Mungbean(Vigna radiata(L.)Wilczek)Genotypes

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 611-625页

作者： Fenglan Zhao Jizhi Jin Meng Yang Franklin Eduardo Melo santiago Jianping Xue Li Xu Yongbo Duan Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants College of Life SciencesHuaibei Normal UniversityHuaibei235000China Department of Soil Science Federal Institute of PiauiUruçuíPiauí64860-000Brazil The Second Affiliated Hospital of Guizhou University of Traditional Chinese Medicine Guiyang550003China

Seed germination with selenium(Se)is promising for producing Se-biofortiﬁed foods.Mungbean(Vigna radiata(L.)Wilczek)sprout is freshly eaten as a salad dressed with sauce,making it superior for Se biofortiﬁcation.Since the Se safety range for the human body is extremely narrow,it is imperative to evaluate the genotypic responses of mungbean sprouts to Se.This study evaluated the Se enrichment capacity and interaction withﬂavonoids and antioxidant systems in sprouts of 20 mungbean germplasms.Selenium treatment was done by immersing mung-bean seeds in 20μM sodium selenite solution for 8 h.Afterward,the biomass,Se amounts,ﬂavonoid(particularly vitexin and isovitexin)contents,antioxidant capacity,and key biosynthetic gene expressions were measured.Sprout Se content was 2.0-7.0μg g^(-1) DW among the 20 mungbean germplasms.Selenium treatment differentially affected the biomass,totalﬂavonoid,vitexin,isovitexin,antioxidant enzyme activities,and antioxidant capacities of the mungbean germplasms.Eight germplasms showed increased biomass(p<0.05),the highest increasing by 127%,but 13 did not phenotypically respond to Se treatment.Seven and six germplasms showed varied levels of vitexin and isovitexin increment after Se treatment,the highest measuring 2.67-and 2.87-folds for vitexin and isovitexin,respectively.Two mungbeanﬂavonoid biosynthesis genes,chalcone synthase(VrCHS)and chalcone isomerase(VrCHI)were signiﬁcantly up-regulated in the germplasms with increased vitexin and isovitexin levels(p<0.05).Moreover,Se enrichment capacity was signiﬁcantly correlated with the vitexin,isovitexin,and antiox-idant capacities.In conclusion,mungbean sprouts could be a useful Se-biofortiﬁed food,but the Se enrichment capacity and nutritional response must be determined for each germplasm before commercialization.

关键词： Antioxidant capacity gene expression genotypic variation isovitexin vitexin selenium

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Human Papillomavirus Within Psoriasis Plaques in a Patient With Psoriasis: A Case Report

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International Journal of Dermatology And Venereology 2024年第1期07卷 55-57页

作者： Lema-Matehu Karen P. Lascano-Gallegos Nathalie P. Palacios-álvarez santiago A. School of Medicine Eugenio Espejo UTE University Quito 170147 Ecuador Department of Dermatology Centro de la Piel Quito 170508

Introduction: Psoriasis may be triggered by several factors, and its pathophysiology is related to inflammatory cellular processes.Case presentation: A 67-year-old man who had been diagnosed with psoriasis 14 years previously developed an outbreak of small erythematous desquamative plaques distributed symmetrically on his arms and trunk. Multiple spiny whitish papules had developed over his previously established psoriasis lesions. The appearance of the papules was consistent with viral warts. The patient was treated with systemic methotrexate injected subcutaneously and oral folic acid, both dosed weekly. This treatment produced good results.Discussion: A remarkable feature of this case is that psoriasis was the first diagnosis and that human papillomavirus (HPV) appeared over widespread erythematous squamous plaques. The pathophysiology of psoriasis is related to inflammatory cellular processes. Some authors have reported that HPV proteins may stimulate keratinocyte proliferation. Others have reported that HPV infection mostly stimulates systemic interleukin 17 production; consequently, HPV infection could provide a better environment for interleukin 17 secretion and facilitate new onset of psoriasis. One report indicated that methotrexate was discontinued in a patient who presented with both pathologies, although we had very good results.Conclusion: Psoriasis and HPV may be pathophysiologically related. HPV may stimulate keratinocyte proliferation and systemic interleukin 17 production, resulting in a better environment for psoriasis. Systemic methotrexate injected subcutaneously resulted in a good outcome in our patient.

关键词： human papillomavirus methotrexate psoriasis case report

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Failure to Rescue as a Quality Metric in Congenital Heart Surgeries in a High-Complexity Service Provider Institution Located in a Middle-Income Country

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Congenital Heart Disease 2024年第2期19卷 207-218页

作者： Gustavo Cruz santiago Pedroza Juan F.Vélez Jessica Largo Juan F.Tejada Jorge H.Mejía-Mantilla Departamento de Anestesiología Fundación Valle del LiliCali760032Colombia Centro de Investigaciones Clínicas Fundación Valle del LiliCali760032Colombia Departamento de Cardiología Pediátrica Fundación Valle del LiliCali760032Colombia Facultad de Medicina Universidad IcesiCali760031Colombia Unidad de Cuidado Intensivo Fundación Valle del LiliCali760032Colombia

Background:Failure to rescue has been an effective quality metric in congenital heart surgery.Conversely,mor-bidity and mortality depend greatly on non-modifiable individual factors and have a weak correlation with better-quality performance.We aim to measure the complications,mortality,and risk factors in pediatric patients undergoing congenital heart surgery in a high-complexity institution located in a middle-income country and compare it with other institutions that have conducted a similar study.Methods:A retrospective observational study was conducted in a high-complexity service provider institution,in Cali,Colombia.All pediatric patients undergoing any congenital heart surgery between 2019 and 2022 were included.The main outcomes evaluated in the study were complication,mortality,and failure to rescue rate.Univariate and multivariate logistic regression analysis was performed with mortality as the outcome variable.Results:We evaluated 308 congenital heart sur-geries.Regarding the outcomes,201(65%)complications occurred,23(7.5%)patients died,and the FTR of the entire cohort was 11.4%.The presence of a postoperative complication(OR 14.88,CI 3.06–268.37,p=0.009),age(OR 0.79,CI 0.57–0.96,p=0.068),and urgent/emergent surgery(OR 8.14,CI 2.97–28.66,p<0.001)were the most significant variables in predicting mortality.Conclusions:Failure to rescue is an effective and comparable quality measure in healthcare institutions and is the major contributor to postoperative mortality in congenital heart surgeries.Despite our higher mortality and complication rate,we obtained a comparable failure to rescue rate to high-income countries’health institutions.

关键词： Congenital heart surgery complication mortality failure to rescue quality metric

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Histopathological impact of SARS-CoV-2 on the liver:Cellular damage and long-term complications

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World Journal of Gastroenterology 2024年第22期30卷 2866-2880页

作者： Alfonso Rodriguez-Espada Moises Salgado-de la Mora Briana Mariette Rodriguez-Paniagua Nathaly Limonde la Rosa Monica Itzel Martinez-Gutierrez santiago Pastrana-Brandes Nalu Navarro-Alvarez Department of Molecular Biology Universidad Panamericana School of MedicineCampus MéxicoMexico 03920Mexico Department of Internal Medicine Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico Department of Surgery University of Colorado Anschutz Medical CampusDenverCO 80045United States PECEM Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoMexico 04360Mexico Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico

Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome,multiple organ failure,and death.Despite extensive studies on the pathogenicity of SARS-CoV-2,its impact on the hepatobiliary system remains unclear.While liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels,the exact source of this damage is not fully understood.Proposed mechanisms for injury include direct cytotoxicity,collateral damage from inflammation,drug-induced liver injury,and ischemia/hypoxia.However,evidence often relies on blood tests with liver enzyme abnormalities.In this comprehensive review,we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients,drawing from liver biopsies,complete autopsies,and in vitro liver analyses.We present evidence of the direct impact of SARS-CoV-2 on the liver,substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes,including mitochondrial swelling,endoplasmic reticulum dilatation,and hepatocyte apoptosis.Additional ly,we describe the diverse liver pathology observed during COVID-19 infection,encompassing necrosis,steatosis,cholestasis,and lobular inflammation.We also discuss the emergence of long-term complications,notably COVID-19-related secondary sclerosing cholangitis.Recognizing the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making.

关键词： Liver SARS-CoV-2 COVID-19 Angiotensin-converting enzyme 2 Histopathology Liver biopsies Liver autopsy In vitro

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