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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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Neurotrophic fragments as therapeutic alternatives to ameliorate brain aging

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Neural Regeneration Research 2023年第1期18卷 51-56页

作者： Itzel Ortiz flores Samuel Treviño Alfonso Díaz Department of Health Sciences School of MedicineUniversity of the Americas PueblaPueblaMexico Faculty of Chemical Sciences Benemerita Autonomous University of PueblaPueblaMexico

Aging is a global phenomenon and a complex biological process of all living beings that introduces various *** this physiological process,the brain is the most affected organ due to changes in its structural and chemical functions,such as changes in plasticity and decrease in the number,diameter,length,and branching of dendrites and dendritic ***,it presents a great reduction in volume resulting from the contraction of the gray ***,aging can affect not only cognitive functions,including learning and memory,but also the quality of life of older *** a result of the phenomena,various molecules with notable neuroprotective capacity have been proposed,which provide a therapeutic alternative for people under conditions of aging or some neurodegenerative *** is important to indicate that in recent years the use of molecules with neurotrophic activity has shown interesting results when evaluated in in vivo *** review aims to describe the neurotrophic potential of molecules such as resveratrol(3,5,4′-trihydroxystilbene),neurotrophins(brain-derived neurotrophic factor),and neurotrophic-type compounds such as the terminal carboxyl domain of the heavy chain of tetanus toxin,cerebrolysin,neuropeptide-12,and *** of these molecules have been evaluated by our research *** suggest that these molecules exert an important therapeutic potential,restoring brain function in aging conditions or models of neurodegenerative ***,our interest is in describing the current scientific evidence that supports the therapeutic potential of these molecules with active neurotrophic.

关键词： Alzheimer’s disease brain cerebral cortex cognitive function dendritic spines HC-TeTx hippocampus neurodegeneration neuronal survival neurotrophins

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Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-Velázquez Alexander J. Jaramillo-Cañas Shania N. Aponte-Paris Gabriela V. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas Pedro L. Cruz-Rosa Idhaliz flores-Caldera Maricarmen Colón-Diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding

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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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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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The body mass index (BMI) as a public health tool to predict metabolic syndrome

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Open Journal of Preventive Medicine 2012年第1期2卷 59-66页

作者： Miguel Murguía-Romero rafael Jiménez-flores rafael Villalobos-Molina María Isabel Mendoza-Ramos Julia Reyes-Reali Santiago C. Sigrist-flores Adolfo René Méndez-Cruz Carrera de Médico Cirujano FES Iztacala UNAM Tlalnepantla México

Objective: To analyze the body mass index (BMI) as an indicator of metabolic alterations, including the metabolic syndrome (MetS), at both individual level and public health level. Method: We recruited 3683 undergraduate students (17 - 24 years old) from México City identifying metabolic alterations, including the MetS, and comparing its prevalence by BMI ranges. We applied a sensitivity analysis to define BMI optimal cut-off point values. Results: We found 14.6% of MetS prevalence with a BMI average of 24.2%, and 34.5% of overweight prevalence (BMI ≥ 25). A BMI cut-off point value of 22.5 is suggested as an upper limit of a normal weight condition, only for public health purpose;while at individual level the BMI cut-off point of 25 was corroborated as the upper limit for a normal weight condition. A public health tool to estimate the MetS prevalence based on BMI percentages is proposed, and a study case is presented. Conclusion: BMI fails predicting at individual level both, healthy condition or metabolic alterations, when values are lower than 25. At population level, the BMI is a valuable public health tool to estimate MetS prevalence: based on the prevalence of MetS by BMI ranges of a sample of the population.

关键词： BMI Metabolic Syndrome Obesity Public Health Tool

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Potential role of noise to improve intracortical microstimulation in tactile neuroprostheses

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Neural Regeneration Research 2021年第8期16卷 1533-1534页

作者： Pedro Mabil Nayeli Huidobro Amira flores Elias Manjarrez Laboratory of Integrative Neurophysiology Instituto de FisiologíaBenemérita Universidad Autónoma de PueblaCPMéxico

The intracortical microstimulation(ICMS) from 40 to 100 μA is useful to elicit tactile sensations,which could be employed in neuroprostheses to control the robotic arms' ***,this electrical current applied for prolonged periods of time could damage the neuronal ***,there is a necessity to create new strategies for the practical use of ICMS in a safe intensity range for potential clinical applications in tetraplegic *** we describe crucial studies supporting the use of electrical and optical noise to guarantee a safe ICMS delivered through brain-machine interface technologies.

关键词： guarantee supporting sensation

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Effect of light on seed germination and seedling shape of succulent species from mexico

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Journal of Plant Ecology 2016年第2期9卷 174-179页

作者： Joel flores Claudia González-Salvatierra Enrique Jurado División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa de San José2055Col.Lomas4SecciónSan Luis PotosíSan Luis Potosí78216México Facultad de Ciencias Forestales Universidad Autónoma de Nuevo LeónCarretera Nacionalkm 145LinaresN.L.67700México

Aims Light requirements for cactus seed germination have been considered to be associated with their adult plant height and seed mass,but this has not been thoroughly studied for other succulent *** order to understand seed photosensitivity from desert species belonging to Asparagaceae(subfamily Agavoideae)and Cactaceae,we performed a germination experiment with and without light for 12 species and 2 varieties from 1 species from the Southern Chihuahuan *** also determined if adult growth is totally determined by seedling‘growth form’in *** We performed a germination experiment using light and darkness for 13 species from Southern Chihuahuan Desert:10 rosette species(Asparagaceae),as well as 1 globose,1 columnar and 2 varieties from 1 depressed-globose species(Cactaceae).The response variables were seed germination percentage and relative light germination(RLG).In addition,in order to determine if adult-globose cacti could have cylindrical seedlings,we calculated the shape index(height/width ratio)for Coryphanta clavata and Mammillaria *** Findings All species were considered neutral *** species had similar seed germination in both light and dark conditions,and three taxa(*** and the two varieties of Ferocactus latispinus)showed higher germination with light than without *** salmiana,*** and the two varieties of *** had higher RLG than the other *** mass was an important factor because with higher seed mass there was lower dependence to *** findings support the hypothesis that small seed mass and light requirements have coevolved as an adaptation to ensure *** adult-globose cactus species,***,and one adult-columnar species,***,had small seeds and neutral *** from these two species exposed to light were cylindrical and those under darkness conditions were *** seeds from this species are able to germinate in

关键词： Asparagaceae Cactaceae Chihuahuan Desert photoblasticism seed germination succulent plants

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Risk assessment of chemical substances of safety concern generated in processed meats

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Food Science and Human Wellness 2019年第3期8卷 244-251页

作者： Monica flores Leticia Mora Milagro Reig Fidel Toldra Instituto de Agroquímica y Tecnología de Alimentos(CSIC) Avenue Agustín Escardino 746980PaternaValenciaSpain Instituto de Ingeniería de Alimentos para el Desarrollo Universitat Politècnica de ValenciaCamino de vera s/n46022ValenciaSpain

This manuscript is reviewing the presence of substances of safety concern that may be generated in different types of meat *** substances include N-nitrosamines that can be generated under certain conditions when using nitrite as preservative,the polycyclic aromatic hydrocarbons generated as a consequence of particular smoking processes,heterocyclic aromatic amines generated under particular cooking conditions,compounds released from the oxidation of lipids and proteins,Maillard reaction products like acrylamide and carboxymethyl lysine,and amines that can be generated and accumulated in fermented *** hazardous compounds,their mechanisms of generation,risks for health and ways of preventing its presence in meat products are briefly described in this review.

关键词： Polycyclic aromatic hydrocarbons Heterocyclic amines Nitrosamines Amino acids oxidation Lipids oxidation Maillard reaction products Biogenic amines

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Description of a Propulsion Unit Used in Guiding a Walking Machine by Recognizing a Three-point Bordered Path

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Chinese Journal of Mechanical Engineering 2016年第6期29卷 1157-1166页

作者： NUNEZ-ALTAMIRANO Diego A JUAREZ-CAMPOS Ignacio MARQUEZ-PEREZ Lucia flores-DIAZ Ociel School of Mechanical Engineering Universidad Michoacana de San Nicolas de Hidalgo Morelia Michoacan Mexico

A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peaucellier-Lipkin mechanism with one degree of freedom is transformed into a more sophisticated parallel kinematic chain by including four more degrees of freedom. The resulting propulsion unit is able to adapt its kinematic structure and reach instant centers of rotation, in accordance with the presence of three points that border a geometric path. A laser sensor mounted on the body of the machine detects each point. Once the machine has detected the exact location of the border of the road, it walks along a curve parallel to that border. Although the proposed research describes only one propulsion unit or leg, the methodology can be applied to all the legs of the walking machine. The novel 5-DOF leg is able to reach different centers of rotation, providing either the concave or convex arcs that satisfy the basic principle of displacement of walking machines.

关键词： Propulsion unit Peaucellier-Lipkin walking machine straight line mechanism.

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