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High pressure effects on the excitation spectra and dipole properties of Li, Be+, and B2+ atoms under confinement

Matter and Radiation at Extremes 2020年第2期5卷 43-52页

作者： C.Martinez-flores R.Cabrera-Trujillo Departamento de Qu´ımica Universidad Aut´onoma Metropolitana IztapalapaSan Rafael Atlixco 186Col.VicentinaIztapalapaC.P.09340 M´exico D.F.Mexico Instituto de Ciencias F´ısicas Universidad Nacional Aut´onoma de M´exicoAp.Postal 43-8CuernavacaMorelos62251Mexico Theoretische Chemie Physikalisch-Chemisches InstitutUniversit¨at HeidelbergINF 22969120 HeidelbergGermany

Properties of atoms and molecules undergo significant changes when subjected to spatial *** study the excitation spectra of lithiumlike atoms in the initial 1s22s electronic configuration when confined by an impenetrable spherical *** implement Slater’s X-αmethod in Hartree–Fock theory to obtain the excitation *** that as the cavity size decreases,the total,2s,2p,and higher excited energy levels ***,we confirm the existence of crossing points between ns–np states for low values of the confinement radius such that the ns→np dipole transition becomes zero at that critical *** crossing points of the s–p states imply that instead of photon absorption,one observes photon emission for cavities with radius smaller than the critical ***,the dipole oscillator strength associated with the 2s→2p transition becomes negative,and for higher pressures,the 2s→3p dipole oscillator strength transition becomes larger than *** validate the completeness of the spectrum by calculating the Thomas–Reiche–Kuhn sum rule,as well as the static dipole polarizability and mean excitation energy of lithium-like *** find that the static dipole polarizability decreases and exhibits a sudden change at the critical pressure for the absorption-to-emission *** mean excitation energy increases as the pressure ***,as a consequence of the critical transition fromabsorption to emission,themean excitation energy becomes undetermined for higher pressures,with implications formaterial damage under extreme *** unconfined systems,our results show good to excellent agreement with data found in the literature.

关键词： transition. excitation dipole

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Occurrence,leaching,and mobility of major and trace elements in a coal mining waste dump:The case of Douro Coalfield,Portugal

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Energy Geoscience 2021年第2期2卷 121-128页

作者： J.Ribeiro D.flores Department of Earth Sciences University of CoimbraRua Silvio Lima3030-790CoimbraPortugal Institute of Earth Sciences-Porto Pole Rua Do Campo Alegre 6874169-007PortoPortugal Environment and Spatial Planning Department of GeosciencesUniversity of PortoRua Do Campo Alegre 6874169-007PortoPortugal

The coal mining residues from past mining activities in the Douro Coalfield are emplaced in many dumps near the mining areas,causing substantial environmental *** study aims to contribute to the investigation of environmental impacts caused by the disposal of the residue in the Douro Coalfield through the determination of the geochemical composition of waste materials collected at 3 e 15 m depth,and of the water-leachable fraction produced by percolation in these materials inside the *** elements with higher concentration in the leachates are Ca,Cd,Co,Mg,Mn,Na,Ni,S,and Zn,indicating that they are the most easily leached and accessible elements for percolation and mobilization into the *** presence of these elements in the leachates is principally attributed to their occurrence as water-soluble ions in clays and sulphides affected by natural weathering conditions,which promotes their breakdown and occurrence as exchangeable *** leachates are classified as acid *** weathering and leaching in the Sao Pedro da Cova waste dump are the principal~paths for chemical elements to be percolated and mobilized to environment,posing risk to the soils,waters and ecosystems in the surrounding areas.

关键词： Coal mining Waste dump Water-soluble compound Hazardous element

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Petiveria alliacea Suppresses Airway Inflammation and Allergen-Specific Th2 Responses in Ovalbumin-Sensitized Murine Model of Asthma

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Chinese Journal of Integrative Medicine 2018年第12期24卷 912-919页

作者： Rosa Martha Perez Gutierrez Jose Maria Mota flores Natural Products Research Laboratory Higher School of Chemical Engineering and Extractive IndustriesInstituto Politecnico Nacional (IPN) Professional Unit Adolfo Lopez Mateos Av. Instituto Politécnico NacionalS/N

Objective： To examine the effect of metanol extract of Petiveria alliacea （PM） on airway inflammation in a murine model of chronic asthma. Methods： Two-month-old male BALB/c mice （n=6-8/group） were sensitized on days 0 and 14 by intraperitoneal injection of 20μg ovalbumin （OVA）. On day 25, the mice received an airway challenge with OVA （3%, w/v, in phosphate buffered saline）. PM was administered orally by oral gavage to mice at doses of 100, 200 and 400 mg/kg body weight once daily from days 18 to 23. Control mice were orally administered phosphate buffered saline （PBS） to induce a model of asthma. At the end of the test, respiratory reactivity was assayed, the total cell number, interleukin-4 （IL-4）, IL-5, IL-13, tumor necrosis factor-alpha （TNF-α） and reactive oxygen species （ROS） in the bronchoalveolar lavage fluid （BALF） were determined and the levels of serum IgE, intercellular cell adhesion molecule 1 （ICAM-1） and eotoxin were measured. In addition, lung tissue was used to qualify the IL-4, IL-5, IL-13, TNF-α and transforming growth factor beta 1 （TGF-β1）. Histologic examination was performed to observe inflammatory cellular infiltration. Results： The administration of PM in comparison with the OVA-only treated group significantly attenuated the infiltration of eosinophUs and other inflammatory cells （P〈0.01）. Airway resistance （RI） in the OVA-only induced group was significantly higher than that of the PBS control group （P〈0.01） when methacholine was added. TNF-α, IgE, TGF-β1 and cytokine levels IL-4, IL-5, IL-β in the BALF decreased compared to control mice （P〈0.01 or P〈0.05）. PM treatment also inhibited the production of chemokines, eotaxin and ICAM-1 in BALF （P〈0.01）, which improved lung function. Histopathological examination revealed that the sensitized treated PM groups had significant lower in inflammatory scores similar to dexamethasone treatments and the untreated group. Conclusion： Administration of PM could inhibit airway inflammation, regulate cyt

关键词： Petiveria alliacea allergy antiinflammation asthma

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Dipole and generalized oscillator strength derived electronic properties of an endohedral hydrogen atom embedded in a Debye-Huckel plasma

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Matter and Radiation at Extremes 2018年第5期3卷 227-242页

作者： C.Martínez-flores R.Cabrera-Trujillo Instituto de Ciencias Físicas Universidad Nacional Autonoma de MexicoAp.Postal 43-8CuernavacaMorelos62251Mexico

We report electronic properties of a hydrogen atom encaged by an endohedral cavity under the influence of a weak plasma interaction. Weimplement a finite-difference approach to solve the Schrodinger equation for a hydrogen atom embedded in an endohedral cavity modeled by theWoods-Saxon potential with well depth V0, inner radius R0, thickness D, and smooth parameter g. The plasma interaction is described by aDebye-Hu¨ckel screening potential that characterizes the plasma in terms of a Debye screening length lD. The electronic properties of theendohedral hydrogen atom are reported for selected endohedral cavity well depths, V0, and screening lengths, lD, that emulate differentconfinement and plasma conditions. We find that for low screening lengths, the endohedral cavity potential dominates over the plasma interaction by confining the electron within the cavity. For large screening lengths, a competition between both interactions is observed. We assessand report the photo-ionization cross section, dipole polarizability, mean excitation energy, and electronic stopping cross section as function of lD and V0. We find a decrease of the Generalized Oscillator Strength (GOS) when the final excitation is to an s state as the plasma screeninglength decreases. For a final excitation into a p state, we find an increase in the GOS as the endohedral cavity well-depth increases. For the caseof the electronic stopping cross section, we find that the plasma screening and endohedral cavity effects are larger in the low-to-intermediateprojectile energies for all potential well depths considered. Our results agree well to available theoretical and experimental data and are afirst step towards the understanding of dipole and generalized oscillator strength dependent properties of an atom in extreme conditions encagedby an endohedral cavity immersed in a plasma medium.

关键词： Oscillator strengths Debye-Huckel plasma Cavities Endohedral Energy loss Stopping power

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Sensitivity-based Vulnerability Assessment of State Estimation

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 886-896页

作者： Gonzalo E.Constante-flores Antonio J.Conejo Jiankang Wang Department of Electrical and Computer Engineering The Ohio State UniversityColumbusUSA Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusUSA

We propose a technique to assess the vulnerability of the power system state estimation. We aim at identifying the measurements that have a high potential of being the target of false data injection attacks. From the perspective of the adversary, such measurements have the following characteristics: ① being influential on the variable estimates;② corrupting their measured values is likely to be undetected. Additionally, such characteristics should not change significantly with the system operation condition. The proposed technique provides a systematic way of identifying the measurements with such characteristics. We illustrate our methodology on a 4-bus system, the New England 39-bus system, and the IEEE 118-bus test system, respectively.

关键词： False data injection attack state estimation sensitivity analysis singular value decomposition

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Computational Chemistry and Molecular Modeling Techniques for the Study of Micropeptin EI-964: Insights into Its Chemical Reactivity and Potential Pharmaceutical Properties

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Computational Molecular Bioscience 2023年第3期13卷 35-47页

作者： Norma flores-Holguín Juan Frau Daniel Glossman-Mitnik Laboratorio Virtual NANOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Chihuahua Mexico Departament de Química Facultat de Ciències Universitat de les Illes Balears Palma de Mallorca Spain

Micropeptin EI-964 is a cyclic peptide compound isolated from a marine cyanobacterium with potent inhibitory activity against serine proteases, particularly chymotrypsin and trypsin. It has shown promising activity against various cancer cell lines, making it a candidate for drug development. The unique structure and activity of Micropeptin EI-964 make it a promising lead compound for the development of novel serine protease inhibitors and anti-cancer drugs. Computational Chemistry and Molecular Modeling techniques can provide valuable insights into the chemical reactivity and pharmaceutical properties of Micropeptin EI-964, guiding the design and development of new compounds with enhanced bioactivity and improved drug-like properties.

关键词： Micropeptin EI-964 Chemical Reactivity Conceptual DFT Computational Pharmacokinetics Pharmaceutical Drugs

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Few-Shot Learning Enables Population-Scale Analysis of Leaf Traits in Populus trichocarpa

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Plant Phenomics 2023年第3期5卷 581-597页

作者： John Lagergren Mirko Pavicic Hari B.Chhetri Larry M.York Doug Hyatt David Kainer Erica M.Rutter Kevin flores Jack Bailey-Bale Marie Klein Gail Taylor Daniel Jacobson Jared Streich Biosciences Division Oak Ridge National LaboratoryOak RidgeTNUSA Department of Applied Mathematics University of CaliforniaMercedCAUSA Department of Mathematics North Carolina State UniversityRaleighNCUSA Department of Plant Sciences University of CaliforniaDavisCAUSA

Plant phenotyping is typically a time-consuming and expensive endeavor,requiring large groups of researchers to meticulously measure biologically relevant plant traits,and is the main bottleneck in understanding plant adaptation and the genetic architecture underlying complex traits at population *** this work,we address these challenges by leveraging few-shot learning with convolutional neural networks to segment the leaf body and visible venation of 2,906 Populus trichocarpa leaf images obtained in the *** contrast to previous methods,our approach(a)does not require experimental or image preprocessing,(b)uses the raw RGB images at full resolution,and(c)requires very few samples for training(e.g.,just 8 images for vein segmentation).Traits relating to leaf morphology and vein topology are extracted from the resulting segmentations using traditional open-source image-processing tools,validated using real-world physical measurements,and used to conduct a genome-wide association study to identify genes controlling the *** this way,the current work is designed to provide the plant phenotyping community with(a)methods for fast and accurate image-based feature extraction that require minimal training data and(b)a new population-scale dataset,including 68 different leaf phenotypes,for domain scientists and machine learning *** of the few-shot learning code,data,and results are made publicly available.

关键词： networks neural image

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Insulin:A connection between pancreaticβcells and the hypothalamus

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World Journal of Diabetes 2023年第2期14卷 76-91页

作者： Brenda De la Cruz Concepción Yaccil Adilene flores Cortez Martha Isela Barragán Bonilla Juan Miguel Mendoza Bello Monica Espinoza Rojo Molecular and Genomic Biology Laboratory Faculty of Chemical-Biological SciencesAutonomous University of GuerreroChilpancingo 39070GuerreroMexico

Insulin is a hormone secreted by pancreaticβ*** concentration of glucose in circulation is proportional to the secretion of insulin by these *** target cells,insulin binds to its receptors and activates phosphatidylinositol-3-kinase/protein kinase B,inducing different mechanisms depending on the cell *** the liver it activates the synthesis of glycogen,in adipose tissue and muscle it allows the capture of glucose,and in the hypothalamus,it regulates thermogenesis and *** in insulin function[insulin resistance(IR)]are related to the development of neurodegenerative diseases in obese ***,in obesity and diabetes,its role as an anorexigenic hormone in the hypothalamus is diminished during ***,hyperphagia prevails,which aggravates hyperglycemia and IR further,becoming a vicious circle in which the patient cannot regulate their need to *** calorie intake induces an increase in reactive oxygen species,overcoming cellular antioxidant defenses(oxidative stress).Reactive oxygen species activate stress-sensitive kinases,such as c-Jun Nterminal kinase and p38 mitogen-activated protein kinase,that induce phosphorylation in serine residues in the insulin receptor,which blocks the insulin signaling pathway,continuing the mechanism of *** brain and pancreas are organs mainly affected by oxidative *** use of drugs that regulate food intake and improve glucose metabolism is the conventional therapy to improve the quality of life of these ***,the use of antioxidants that regulate oxidative stress has given good results because they reduce oxidative stress and inflammatory processes,and they also have fewer side effects than synthetic drugs.

关键词： Insulin Pancreas Hypothalamus Hyperphagia Hyperglycemia Stress

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Genetic Screening of Halothane Gene on Selected Philippine Native Pig Herds

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Open Journal of Genetics 2023年第3期13卷 105-113页

作者： Sherwin Dapiawen Matias Maureen Basa Gajeton Ester Battad flores Animal Breeding and Genomics Section Philippine Carabao Center National Headquarters and Genepool Science City of Munoz Nueva Ecija Philippines

The establishment of nucleus herds (NHs) of Native Pigs (NPs) at various R&D stations in the Philippines is currently being undertaken for food security and genetic conservation advocacy. Marker-assisted selection (MAS) is being utilized to identify individuals carrying favorable alleles of genes associated with production traits and screen out genetic defects (GD) for breeding purposes. Porcine Stress Syndrome (PSS) caused by a mutation in Halothane (HAL) gene is a GD frequently found in commercial breeds that when expressed, causes pale, soft, exudative (PSE) meat. PSE is inferior quality meat undesirable in the market causing economic losses to the swine industry. Thus, this study was conducted to screen the HAL gene through mutagenically separated-polymerase chain reaction (MSPCR) in selected NP herds and assessed its repeatability in local breeds. Results showed that out of 577 screened individuals, 543 (94.11%) were normal (NN), 0 (0%) were homozygous mutant (nn) and 34 (5.89%) were heterozygous carriers (Nn). Therefore, the optimized PSS screening protocol using MSPCR is also applicable to local breeds. As such, the availability of genetic tests for PSS could be useful in improving the Philippine NPs breeding selection and inhibiting or eliminating PSS mutant incidence within its nucleus herd.

关键词： Halothane Gene Porcine Stress Syndrome Native Pig

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True grit: ingestion of small stone particles by hummingbirds in West Mexico

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Avian Research 2021年第4期12卷 739-749页

作者： Omar Maya-García Mauricio Ortega-flores Jorge E.Schondube Posgrado en Ciencias Biológicas Unidad de PosgradoCoordinación del Posgrado en Ciencias BiológicasUniversidad Nacional Autónoma de MéxicoEdificio D1er pisoCircuito de PosgradosCiudad UniversitariaDel.CoyoacánC.P.04510 México D.F.Mexico Laboratorio de Ecología Funcional Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro No.8701Col.Ex Hacienda de San Joséde la HuertaC.P.58190 MoreliaMichoacánMexico

Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and *** feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West ***: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin ***: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican ***: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;how

关键词： Arthropod chitin content Arthropod digestion Breeding season Mineral nutritional requirements

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