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Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.guerra S.Castro-Lopes J.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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Journal of Mountain Science 2024年第9期21卷 2986-3000页

作者： Anthony guerra Fressia N.AMES-MARTÍNEZ Ernesto C.RODRÍGUEZ-RAMÍREZ Postgraduate Programme in Agronomy/Plant Physiology department of Biology-Institute of Natural Sciences Federal University of LavrasLavras 37203-202Minas Gerais 30000-31999Brazil Laboratory of Biotechnology and Molecular Biology Continental UniversitySan Antonio UrbanizationHuancayo 12000Peru Ecology and Biodiversity Research Programme ANDINUS AssociationMiguel Grau Street 370Huancayo 12000Peru dendrochronology Laboratory Continental UniversitySan Carlos Avenue 1980Huancayo 12000Peru

Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate *** anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme *** the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem *** address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric *** performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic *** wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis *** study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel *** findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna *** evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and ada

关键词： Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress

Small Cell Neuroendocrine Carcinoma of the Vulva: Case Report and Literature Review

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Open Journal of Obstetrics and Gynecology 2024年第2期14卷 295-300页

作者： Gabriela Françóes Rostirolla Alessandra guerra Maria Carolina Rey Alt Luiza Tesser Dalla Libera Maria Eduarda Appel Binda Márcia Appel Fernando de Marco dos santos department of Obstetrics and Gynecology Caxias do Sul University Caxias do Sul Brazil department of Pathology UNIVATES Lajeado RS Medical Student Caxias do Sul University Caxias do Sul Brazil department of Obstetric and Gynecology Federal University of Rio Grande do Sul Porto Alegre Brazil department of Oncology Surgeon Caxias do Sul University Caxias do Sul Brazil

Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. When present, these neoplasms often manifest with nonspecific signs and symptoms such as pain, itching, swelling, single-focus lesions, bleeding, and enlargement of inguinal lymph nodes, in addition to the presence of progressively enlarging vulvar nodules. Consequently, the diagnostic investigation involves histopathological examination and confirmation through immunohistochemistry. Objective: To present a comprehensive understanding of this rarely studied pathology. The primary objective is to provide valuable insights that could aid in the future development of universally applicable treatment guidelines. Case Presentation: A 57-year-old female, with no prior comorbidities, menopause at 36, who presented with a left vulvar nodule accompanied by intense pain and swelling, later diagnosed with small cell neuroendocrine carcinoma in the vulva. Conclusion: This case report highlights the importance of enhancing our knowledge regarding small cell neuroendocrine carcinoma in the vulva, given its scarcity in medical literature. The information presented here underscores the need for standardized diagnostic and treatment approaches, paving the way for future consensus on managing this uncommon but challenging neoplasm.

关键词： Vulvar Neoplasms Carcinoma Small Cell Carcinoma Neuroendocrine Genital Neoplasms Female Vulvar Diseases

Portal vein arterialization in 25 liver transplant recipients:A Latin American single-center experience

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World Journal of Transplantation 2024年第2期14卷 135-147页

作者： Nicolas Andres Cortes-Mejia Diana Fernanda Bejarano-Ramirez Juan Jose guerra-Londono Diego Rymel Trivino-Alvarez Raquel Tabares-Mesa Alonso Vera-Torres Division of Anesthesiology Critical Care Medicineand Pain MedicineThe University of Texas MD Anderson Cancer CenterHoustonTX 77030United States Transplant and Hepatobiliary Surgery department Fundacion Santa Fe de BogotaBogota 110111Colombia General Surgery department Fundacion Santa Fe de BogotaBogota 110111Colombia

BACKGROUND Portal vein arterialization(PVA)has been used in liver transplantation(LT)to maximize oxygen delivery when arterial circulation is compromised or has been used as an alternative reperfusion technique for complex portal vein thrombosis(PVT).The effect of PVA on portal perfusion and primary graft dysfunction(PGD)has not been *** patients receiving PVA and LT at the Fundacion santa Fe de Bogota between 2011 and 2022 were *** account for the time-sensitive effects of graft perfusion,patients were classified into two groups:prereperfusion(pre-PVA),if the arterioportal anastomosis was performed before graft revascularization,and postreperfusion(post-PVA),if PVA was performed *** pre-PVA rationale contemplated poor portal hemodynamics,severe vascular steal,or ***-PVA was considered if graft hypoperfusion became *** interventions were attempted before PVA.

关键词： Liver transplantation Portal vein arterialization Arteriovenous anastomoses Portal hypertension Portal vein thrombosis Spontaneous portosystemic shunts Vascular steal phenomenon Primary graft dysfunction Early allograft dysfunction

Influence of wire spacing and plate spacing on electrostatic precipitation of nanoparticles: An approach involving electrostatic shielding and diffusion charging

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Particuology 2023年第9期80卷 127-139页

作者： Felipe de Aquino Lima Vádila Giovana guerra department of Chemical Engineering Federal University of São CarlosRodovia Washington LuísKm 235C.P.676CEP 13560-970São CarlosSPBrazil

Electrostatic precipitation is a process widely used as gas cleaning device,to removal particles from gas ***,in a conventional and well-sized precipitator,the collection efficiency decreases for ultrafine particles,making it difficult to employ this equipment for controlling nanoparticle *** paper investigates the influence of plate spacing(4 and 6.5 cm)and wire spacing(4,6,and 12 cm)on the electric current and nanoparticle collection efficiency,considering the effect of diffusion charging and electrostatic *** laboratory-scale dry wire-plate electrostatic precipitators with different plate spacings were tested for the collection of nanoparticles(6.15–241.4 nm)at three air velocities(1.9,2.9,and 3.9 cm/s).The results demonstrated the effectiveness of the equipment in removing nanoparticles(99.9%)under the highest electric *** values of the wire spacing led to increases in the current and the collection *** was associated with reduced electrostatic shielding,which is more evident in smaller ducts with a higher density of field *** is expected that the findings should improve knowledge on electrostatic precipitation of nanoparticles,enabling optimization of collection efficiency by considering the effects of geometric parameters.

关键词： Electrostatic precipitation Nanoparticles Collection efficiency Plate spacing Wire spacing

Neuropsychological Profile of a Patient with Acquired Brain Damage Following Vascular Lesion of the Left Anterior Cingulate Cortex

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Neuroscience & Medicine 2024年第1期15卷 66-75页

作者： Jimmy Zúñiga-Márquez Lina Borda-Camargo Diego Buitrago-Mora Lorely guerra-Valdés Laura González Patricia Quintero-Cusgüen Nataly Gutierrez-Ávila Hospital Universitario de la samaritana Bogotá Colombia Neuropsychological Assessment and Diagnosis Graduate Program School of Psychology Universidad San Buenaventura Bogotá Bogotá Colombia

Stroke is a physiological alteration associated with changes in blood flow that can result in sudden-onset cognitive impairment. It has a heterogenous clinical presentation with varying degrees of severity correlated with specific central nervous system zones or areas, and its prognosis is uncertain. This case study describes a 62-year-old male patient with acquired brain damage of the anterior cingulate cortex as a result of an ischemic event in the territory of the left anterior cerebral artery. Cognitive function was assessed using the neuropsychological executive function and frontal lobe test battery (BANFE-2) as well as other neuropsychological tests. The results show a profile of higher mental functions characterized by the presence of dysexecutive syndrome with marked behavioral alteration and diencephalic amnesia. .

关键词： Ischemic Stroke Anterior Cingulate Cortex Neuropsychology Acquired Brain Damage

Litter decomposition and nutrient release for two tropical N-fixing species in Rio de Janeiro,Brazil

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Journal of Forestry Research 2022年第2期33卷 487-496页

作者： David Pessanha Siqueira Giovanna Campos Mamede Weiss de Carvalho JoséGabriel de Souza Silva Marcos Vinicius Winckler Caldeira deborah guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto Lamego2000Campos dos GoytacazesRio de JaneiroBrazil departamento de Ciências Florestais e da Madeira Universidade Federal do Espírito SantoAvenida Governador Lindenberg316Jerônimo MonteiroEspírito SantoBrazil department of Geosciences and Natural Resources Management University of CopenhagenRolighedsvej 23Frederisksberg CDenmark

Litter production and decomposition are critical to forest productivity,nutrient cycling,and carbon seques-tration in tropical woody ***,nutrient release and leaf litter stoichiometry in tropical legume tree plantations over the long term after outplanting are poorly understood or even *** improving our under-standing of the pattern of changes in the decomposition of N-fixing leaf litters and their possible impact on carbon stor-age,we measured litter production,mass loss and nutrient release for 240 d during litter decomposition for two tropical legume tree species(Plathymenia reticulata and Hymenaea courbaril),in Rio de Janeiro,*** production for *** was 5.689 kg ha^(−1) a^(−1) and 3.231 kg ha^(−1) a^(−1) for *** patterns of mass loss rates were similar;however,nutrient release was greater for ***,while *** showed immobilization of nutrients,especially for N,which increased by almost 20%in the early phase of decomposition followed by gradual *** from the N-fixing species did differ in nutrient chemistries over time,which was not surprising given that initial nutrient concentrations varied broadly,except for C and *** of the nutrient concentrations increased as the remaining litter mass decreased in both species,except for C and *** C:N and N:P ratios differed between the species,but N:P did not correlate to mass *** species had N-rich leaves,but *** decomposition was very likely P-limited,while *** seemed to be co-limited by N and *** results showed different patterns in nutrient release and the stoichi-ometry involved in the decomposition dynamics of the two tropical N-fixing species,even though they have similar litter decay *** species,but especially ***,may help re-establish nutrient cycling in disturbed ecosystems.

关键词： Nutrient dynamics Legume species Litter chemistry Ecological stoichiometry Tropical forest

Scattering and absorption imaging of a highly fractured fluid-filled seismogenetic volume in a region of slow deformation

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Geoscience Frontiers 2020年第3期11卷 989-998页

作者： Ferdinando Napolitano Luca de Siena Anna Gervasi Ignazio guerra Roberto Scarpa Mario La Rocca Dipartimento di Fisica“E.R.Caianiello” Universita Degli Studi di SalernoVia Giovanni Paolo IIFiscianoSA84084Italy Institute of Geosciences Johannes Gutenberg University MainzJ.-J.-Becher-Weg 21MainzD-55128Germany University of Aberdeen School of GeosciencesGeology and Petroleum GeologyMeston BuildingKing’s CollegeAberdeenScotlandAB243UEUK Dipartimento di Biologia Ecologia e Scienze Della TerraUniversit a Della CalabriaPonte P.BucciArcavacata di RendeCS87036Italy Istituto Nazionale di Geofisica e Vulcanologia Sezione di Rende(CS)Ponte P.BucciArcavacata di RendeCS87036Italy

Regions of slow strain often produce swarm-like sequences,characterized by the lack of a clear mainshockaftershock *** comprehension of their underlying physical mechanisms is challenging and still *** used seismic recordings from the last Pollino swarm(2010-2014) and nearby to separate and map seismic scattering(from P peak-delays) and absorption(from late-time coda-wave attenuation) at different frequencies in the Pollino range and ***-scattering and high-absorption anomalies are markers of a fluid-filled fracture volume extending from SE to NW(1.5-6 Hz) across the *** increasing frequency,these anomalies approximately cover the area where the strongest earthquakes occurred from the sixteenth century until *** our interpretation,the NW fracture propagation ends where carbonates of the Lucanian Apennines begin,as marked by a high-scattering and low-absorption *** the highest frequency(12 Hz) the anomalies widen southward in the middle of the range,consistently marking the faults active during the recent Pollino *** results suggest that fracture healing has closed small-scale fractures across the SE faults that were active in the past centuries,and that the propagation of fluids may have played a crucial role in triggering the 2010-2014 Pollino *** that the fluid propagation ended at the carbonates barrier in the NW direction,fractures opened new paths to the South,favoring the nucleation of the last Pollino ***,the recently active faults in the middle of the seismogenic volume are marked by a high-scattering and highabsorption *** work provides evidence that attenuation parameters may track shape and dynamics of fluid-filled fracture networks in fault areas.

关键词： Polling Seismic attenuation Scattering Fluids Fractures Healing

Effect of Mushroom Extract Hericium erinaceus on Spatial Memory and Morphology of Neurons in the CA1 and CA3 Regions of the Hippocampus in Ovariectomized Rats

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Open Journal of Veterinary Medicine 2024年第7期14卷 163-179页

作者： Lucia Garcia-delgado Mariana Monserrath Verdía-Venegas Jacinto Bañuelos-Pineda Esther Albarrán-Rodríguez Guillermo Nolasco-Rodriguez José Ricardo Cuellar-Pérez Sergio Fausto-guerra Manuel Rosales-Cortés Master in Behavioral Sciences Institute of Neurosciences University of Guadalajara Zapopan Mexico department of Veterinary Medicine Division of Veterinary Sciences CUCBA University of Guadalajara Zapopan Mexico Botany and Zoology Laboratory CUCBA University of Guadalajara Zapopan Mexico

Various studies indicate that low levels of estradiol negatively impact cognitive abilities. Extracts from the fungus Hericium erinaceus (HE) contain bioactive components that promote the proper functioning of the nervous system and potential effects on protection against neurodegenerative diseases, including dementia and motor dysfunctions. The objective was to evaluate the effects of the administration of the HE mushroom extract on visuospatial memory and morphology of neurons in the CA1 and CA3 regions of the hippocampus in ovariectomized rats. 40 young Wistar rats weighing 90 ± 10 g BW were used, which were distributed into four groups of 10 animals;Control Group, non-ovariectomized and untreated rats;Group E2, ovariectomized rats treated with estradiol (2 μg/kg/body weight);Group HE, ovariectomized rats treated with the extract of the fungus Hericium erinaceus (0.5 mg/kg body weight) and Group Ovx/ST, ovariectomized rats, without treatment. The animals were tested in the Barnes and Open Field maze, then they were sacrificed, and their brains were obtained to perform a histological analysis of neuronal morphology in the CA1 and CA3 areas of the hippocampus. The most outstanding results showed that the Ovx/ST group recorded the longest time to arrive at the escape box and stay in the Barnes maze. A correlation was observed between neuronal damage and function;in the groups that did not present satisfactory performance in the maze tests, morphological alterations were identified such as the presence of some neuronal somata with degeneration characteristics such as pyknosis, nuclear basophilia and shrinkage of the cells. Its soma, as well as a decrease in the nuclear area of CA1 and CA3 neurons. It is concluded that the fungus Hericium erinaceus exerted a neuroprotective effect on the neuronal bodies of the hippocampus, associated with better performance in the visuospatial recognition memory test.

关键词： Ovariectomized Rats Ovarian Hypofunction Estradiol Hericium erinaceus Barnes Circular Labyrinth Open Field Labyrinth