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Development and Test of an Experimental Apparatus to Study Thermal-Choking in Ideal Gases and Self-decomposition in Superheated N2O

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Journal of Energy and Power Engineering 2015年第1期9卷 25-39页

作者： Patrick Lemieux Alberto Fara pablo sanchez William Murray California Polytechnic State University San Luis Obispo CA 93407 USA Politecnico di Torino Turin 10129 Italy

N2O represents a popular oxidizer for hybrid rocket motors for a variety of reasons, including safety, ease of access and self-pressurization. It is often used as a saturated two-phase fluid in these applications to take advantage of self-pressurization. Recent interest in using this oxidizer in regeneratively cooled engines requires a detailed heat transfer process analysis to the coolant, in order to quantify performance. Since the injection of N2O typically takes place in the two-phase region, our study focuses on heat transfer rates in this region, and extends the region to include superheated vapor. This analysis is critical for these cooling applications, because the exothermic decomposition nature of N2O also means that unchecked heating in the superheated region may result in a runaway reaction in the cooling passages. Furthermore, provided that sufficient heat transfer rates are available, N2O is expected to accelerate in the cooling passages due to Rayleigh flow effects much like those of a calorically perfect gas. The proximity of superheated N2O to its saturated vapor curve, at the conditions studied here, makes the suitability of a perfect gas model questionable, but that benchmarks is still useful. This paper presents the development of an experimental apparatus （a ＂Rayleigh tube＂）, specifically designed to study this problem, and test the analytical methods developed to model it. Since we focus on the development of the apparatus, the data presented were uses primarily calorically perfect gas surrogates, but the goal is to apply the apparatus and method to N2O. The design and construction of the Rayleigh tube is presented, along with preliminary results with perfect gases. Finally, we present preliminary results on heated N2O flow. Using a simple model for predicted dry-out point, we investigate where superheating may be expected to occur. We present estimates of critical heating and compare them to the heat required to achieve self-decomposition.

关键词： Self-decomposition N2O Rayleigh apparatus

2-Nitrobenzofuran as Dienophile in Polar Diels-Alder Reaction： A Simple Dibenzofurans Synthesis

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Journal of Chemistry and Chemical Engineering 2010年第11期4卷 54-59页

作者： Claudia Daniela Della Rosa Juan pablo sanchez Maria Nelida Kneeteman Pedro Maiximo Emilio Mancini Area Organic Chemistry Chemistry Department Chemical Engeeniering School Litoral National University Santa Fe Argentine

2-nitrobenzofuran is studied as dienophile in polar thermal Diels-Alder reactions with normal electron demand using several structurally different dienes. A very strong electron-acceptor group, such as nitro group, enhances the dienophilic character of these heterocyclic compounds and owing to the fact that this substituent is easily extruded under thermal conditions this reaction sequence becomes a simple method of organic compound＇s families with heteroatom rings preparation. Part of this work is specifically concerned with theoretical studies. The global and local electrophilicity and nucleophilicity indexes were calculated for the dienophile and dienes used in this work. A concise synthesis of dibenzofurans has been development via cycloaddition reactions.

关键词： 2-Nitrofurane dienophile Diels-Ader dibenzofurans.

Prevalence of and risk factors for erectile dysfunction in young nondiabetic obese men:results from a regional study

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Asian Journal of Andrology 2020年第4期22卷 372-378页

作者： María Molina-Vega Maite Asenjo-Plaza María JoséBanderas-Donaire María Dolores Hernández-Ollero Silvia Rodríguez-Moreno Juan Jálvarez-Millán pablo Cabezas-sanchez Fernando Cardona-Díaz Juan Alcaide-Torres Lourdes Garrido-Sánchez Daniel Castellano-Castillo Francisco J Tinahones JoséC Fernández-García Department of Endocrinology and Nutrition Virgen de la Victoria University Hospital(IBIMA)Málaga UniversityMálaga 29010Spain Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición(CIBEROBN) Instituto de Salud Carlos IIIMadrid 28029Spain Cruz de Humilladero Primary Care Center Málaga 29010Spain Teatinos Primary Care Center Málaga 29010Spain Chemical Sanitary Consulting(CQS Lab) Madrid 28003Spain

Erectile dysfunction(ED),a condition closely related to cardiovascular morbidity and mortality,is frequently associated with *** this study,we aimed to determine the prevalence of ED and evaluate the associated risk factors in a cohort of 254 young(18–49 years)nondiabetic obese(body mass index[BMI]≥30 kg m−2)men from primary *** function(International Index of Erectile Function[IIEF-5]questionnaire),quality of life(Aging Males'Symptoms[AMS scale]),and body composition analysis(Tanita MC-180MA)were *** testosterone was determined using high-performance liquid chromatography–mass *** logistic regression analysis was used to study the factors associated with *** prevalence was 42.1%.Subjects with ED presented higher BMI,waist circumference,number of components of the metabolic syndrome,AMS score,insulin resistance,and a more unfavorable body composition than those without *** logistic regression analysis showed that a pathological AMS score(odds ratio[OR]:4.238,P40%of subjects.A pathological AMS score,the degree of obesity,and age were positively associated with ED,while elevated HDL-cholesterol levels were inversely associated with the odds of presenting *** prospective studies are needed to evaluate the long-term consequences of ED in this population.

关键词： Aging Males'Symptoms score erectile dysfunction International Index of Erectile Function-5 questionnaire obesity testosterone

Navigating medial patellotibial ligament reconstruction:Clinical perspectives and surgical strategies

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World Journal of Clinical Cases 2025年第1期13卷 6-10页

作者： Juan pablo Zicaro Ignacio Garcia-Mansilla Division of Knee Hospital Italiano de Buenos AiresBuenos Aires 1109Argentina

The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when *** medial patellotibial ligament and the medial patellomeniscal ligament are secondary stabilizers of the *** this,both the medial patellotibial and patellofemoral ligaments aid in patellar rotation and tilt when the knee is flexed beyond 45°.The medial patellotibial ligament plays a particularly important role in the final stages of stretching in extension and between 40 degrees to 90 degrees of *** clinical relevance and surgical indications for medial patellotibial ligament reconstruction associated with medial patellofemoral ligament reconstruction are still *** editorial explores the surgical indications and clinical results for medial patellotibial ligament reconstruction to improve readers’understanding of this technique,especially because reported clinical outcomes have remained sparse.

关键词： Medial patellotibial ligament Patellar instability Reconstruction Surgical

Protein Shuttle between Nucleus and Cytoplasm:New Paradigms in the ABI5-dependent ABA Responses

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Molecular Plant 2019年第11期12卷 1425-1427页

作者： Inmaculada sanchez-Vicente pablo Albertos Oscar Lorenzo Dpto.de Botanica y Fisiologia Vegetal Instituto Hispano-Luso de Investigaciones Agrarias(CIALE)Facultad de BiologiaUniversidad de SalamancaC/Rio Duero 1237185 SalamancaSpain Present address:Biotechnology in Horticultural Crops TU Munchen-WeihenstephanLiesel-Beckmann-Strasse 185354 FreisingGermany

Plant survival depends on seed germination,progression through post-germinative developmental checkpoints,and adaptation to abiotic *** these processes underlie a tightly controlled regulation by the stress hormone abscisic acid(ABA)at different levels,even though the main research focuses on changes in transcript and protein ***,protein fate undergoes complex readjustments that allow signal transduction to be integrated into physiological *** them,protein redox status,stability,capacity of oligomerization,formation of complexes,and subcellular compartmentalization become key points for plant reprogramming against stresses to acquire an optimal *** this Spotlight,we highlight and discuss the latest advances in dissecting the mechanisms driving protein dynamics of nucleocytoplasmic trafficking in the cell and its relevance for regulating the stability of ABI5 and the ABI5-dependent AB A signaling pathway(Figure 1).

关键词： Figure driving programming

Inflammasome links traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1644-1664页

作者： Gabriela Seplovich Yazan Bouchi Juan pablo de Rivero Vaccari Jennifer C.Munoz Pareja Andrew Reisner Laura Blackwell Yehia Mechref Kevin K.Wang J.Adrian Tyndall Binu Tharakan Firas Kobeissy Department of Surgery Morehouse School of MedicineAtlantaGAUSA Department of Neurobiology Center for NeurotraumaMultiomics&Biomarkers(CNMB)Neuroscience InstituteMorehouse School of MedicineAtlantaGAUSA Department of Neurological Surgery and the Miami Project to Cure Paralysis University of Miami Miller School of MedicineMiamiFLUSA Division of Pediatric Critical Care Department of PediatricsUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Pediatrics Emory UniversityAtlantaGAUSA Department of Neurosurgery Children’s Healthcare of AtlantaAtlantaGAUSA Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTXUSA Morehouse School of Medicine AtlantaGAUSA

Traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease are three distinct neurological disorders that share common pathophysiological mechanisms involving neuroinflammation. One sequela of neuroinflammation includes the pathologic hyperphosphorylation of tau protein, an endogenous microtubule-associated protein that protects the integrity of neuronal cytoskeletons. Tau hyperphosphorylation results in protein misfolding and subsequent accumulation of tau tangles forming neurotoxic aggregates. These misfolded proteins are characteristic of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease and can lead to downstream neuroinflammatory processes, including assembly and activation of the inflammasome complex. Inflammasomes refer to a family of multimeric protein units that, upon activation, release a cascade of signaling molecules resulting in caspase-induced cell death and inflammation mediated by the release of interleukin-1β cytokine. One specific inflammasome, the NOD-like receptor protein 3, has been proposed to be a key regulator of tau phosphorylation where it has been shown that prolonged NOD-like receptor protein 3 activation acts as a causal factor in pathological tau accumulation and spreading. This review begins by describing the epidemiology and pathophysiology of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease. Next, we highlight neuroinflammation as an overriding theme and discuss the role of the NOD-like receptor protein 3 inflammasome in the formation of tau deposits and how such tauopathic entities spread throughout the brain. We then propose a novel framework linking traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease as inflammasomedependent pathologies that exist along a temporal continuum. Finally, we discuss potential therapeutic targets that may intercept this pathway and ultimately minimize long-term neurological decline.

关键词： Alzheimer's disease caspase-1 chronic traumatic encephalopathy inflammasomes neurodegeneration neuroinflammation NLRP1 NLRP3 pyroptosis tauopathy traumatic brain injury

Main environmental variables influencing the abundance of plant species under risk category

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Journal of Forestry Research 2022年第4期33卷 1209-1217页

作者： pablo Antúnez División de Estudios de Posgrado Universidad de la Sierra Juárez68725 Oax.México

Determining climatic and physiographic variables in Mexico’s major ecoregions that are limiting to biodiversity and species of high conservation concern is essential for their ***,at the national level to date,few studies have been performed with large data sets and crossconfirmation using multiple statistical ***,we used 25 endemic,rare and endangered species from 3610 sampling points throughout Mexico and 25 environmental attributes,including average precipitation for different seasons of the year,annual dryness index,slope of the terrain;and maximum,minimum and average temperatures to test our hypothesis that these species could be assessed with the same weight among all variables,showing similar indices of *** results using principal component analysis,covariation analysis by permutations,and random forest regression showed that summer precipitation,length of the frost-free period,spring precipitation,winter precipitation and growing season precipitation all strongly influence the abundance of tropical *** contrast,annual precipitation and the balance at different seasons(summer and growing season)were the most relevant variables on the temperate region *** dry areas,the minimum temperature of the coldest month and the maximum temperature of the warmest month were the most significant *** these different associations in different climatic regions could support a more precise management and conservation plan for the preservation of plant species diversity in forests under different global warming scenarios.

关键词： Correlative models Climate change Effect of topography Endemic species IUCN list Machine learning algorithms

On the interaction of a donepezil-huprine hybrid with synthetic membrane models

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Neural Regeneration Research 2023年第2期18卷 333-334页

作者： pablo Zambrano Max Planck Institute of Biochemistry Cellular and Molecular BiophysicsMunichGermany

Alzheimer's disease is the most prevalent type of dementia today,discovered and described by Alois Alzheimer in *** to the World Alzheimer Report 2021,75%of people with dementia worldwide are undiagnosed,equivalent to 41 million people(Gauthier et al.,2021).With each passing year,the number of people affected by these diseases is increasing,and the estimates of suffering from them in the future are growing.

关键词： Alzheimer diseases

Chemokines and Chemokine Receptors:Their Manifold Roles in Homeostasis and Disease

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Cellular & Molecular Immunology 2004年第2期1卷 95-104页

作者： pablo Iribarren Laboratory of Molecular Immunoregulation Center for Cancer ResearchNational Cancer Institute at FrederickFrederickMarylandUSA

Chemokines are a superfamily of small proteins that bind to G protein-coupled receptors on target cells and were originally discovered as mediators of directional migration of immune cells to sites of inflammation and *** recent years,it has become clear that the function of chemokines extends well beyond the role in leukocyte *** participate in organ development,angiogenesis/angiostasis,leukocyte trafficking and homing,tumorigenesis and metastasis,as well as in immune responses to microbial ***, chemokines and their receptors are important targets for modulation of host responses in pathophysiologicai conditions and for therapeutic intervention of human *** & Molecular Immunology.2004;1(2): 95-104.

关键词： chemokine receptor development leukocyte homing angiogenesis metastasis