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Crystal lattice free volume in a study of initiation reactivity of nitramines:Friction sensitivity

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Defence Technology（防务技术） 2018年第2期14卷 132-136页

作者： Svatopluk Zeman Ning Liu marcela Jungová Ahmed K.Hussein Qi-long Yan Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCZ-532 10PardubiceCzech Republic Xi'an Modern Chemistry Research Institute Xi'anShaanxi710065China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072ShaanxiChina

The relationship between friction sensitivity(FS) and the crystal lattice free space per molecule, △V. of thirteen nitramines is described by a linear equation, divided into a number of the partial relationships with strong limitations by their molecular structure characteristics. Increasing FS due to raising of the △V values is not clearly confirmed. The influence of the △V values on friction sensitivity of nitramines is similar to that of their aza atoms which influence the mutual orientations of nitro groups in neighboring molecules. The dipole-dipole interaction of the oxygen and nitrogen atoms of nitro groups in neighboring nitramine molecules has a major effect on their own FS. In accordance with this interaction, a directly proportional relationship was derived between FS and the intrinsic gas phase molecular volume, V_(int), of the nitramines mentioned, which is divided also into several straight lines according to relatively tight molecular structure similarity. The relationships found again confirm a level of disorder in the distribution of the forces in the crystal lattice of the "common" quality of ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, in comparison with its reduced sensitivity(RS) or chemically pure analogue.

关键词： Crystal lattice Friction Initiation reactivity Nitramines

Retention and redistribution of biological legacies generate resource sinks in silvopastoral systems of Arid Chaco forests

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Ecological Processes 2019年第1期8卷 344-359页

作者： Laura Cavallero marcela Ledesma Dardo R.López Carlos A.Carranza Centro Científico Tecnológico(CCT)CONICET Córdoba CórdobaArgentina Estación Forestal INTA-Villa Dolores(EEA Manfredi) CórdobaArgentina

Background:Forests are used for multiple purposes worldwide,which often include timber harvest,firewood extraction and livestock *** excessive pressure on multipurpose systems may decrease soil cover,promoting soil erosion and causing the loss of other resources,as litter and *** forestry practices can help to decrease or mitigate resource loss in the managed ***,retaining and redistributing biological legacies(***,branches,woody debris)at strategic locations can create sediment,litter,and seed-sinks in the silvopastoral *** addition,grazing management could increase or,even,decrease the success of this *** this study,we assessed the effect of branch barriers and grazing management on resource run-off/runon processes in silvopastoral systems of Arid Chaco(Córdoba,Argentina).To do this,a 2-ha area was divided in two paddocks that were randomly assigned to different grazing managements:winter *** *** randomly selected 22 water run-off paths in each paddock,and in the half of them,we build elongated branch *** each run-off path(with and without branch barriers),we recorded the amount of accumulated and lost sediment(during the rainy season),litter biomass,germinable seed bank,richness and cover of plant species,and richness and density of seedlings and saplings of woody ***:Branch barriers promoted sediment accumulation during the first and the second year of the study,depending on grazing *** temporal and spatial scale of the effect of the branch barriers also depended on grazing *** barriers also trapped litter and seeds,which may have increased the richness and density of seedlings and saplings of woody ***:By intercepting the dominant flow of erosive agents,branch barriers trapped sediment,litter,and propagules of different species.A greater amount of sediment and litter would have improved microsite quality,favouring seed germination an

关键词： Branch barriers Ecosystem degradation Multipurpose forests Soil erosion Winter grazing

Pathological correlations between traumatic brain injury and chronic neurodegenerative diseases

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Translational Neurodegeneration 2017年第1期6卷 187-196页

作者： marcela Cruz-Haces Jonathan Tang Glen Acosta Joseph Fernandez Riyi Shi Weldon School of Biomedical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Basic Medical Sciences Purdue UniversityWest LafayetteUSA

Traumatic brain injury is among the most common causes of death and disability in youth and young *** addition to the acute risk of morbidity with moderate to severe injuries,traumatic brain injury is associated with a number of chronic neurological and neuropsychiatric sequelae including neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s ***,despite the high incidence of traumatic brain injuries and the established clinical correlation with neurodegeneration,the causative factors linking these processes have not yet been fully *** from removal from activity,few,if any prophylactic treatments against post-traumatic brain injury neurodegeneration ***,it is imperative to understand the pathophysiological mechanisms of traumatic brain injury and neurodegeneration in order to identify potential factors that initiate neurodegenerative *** stress,neuroinflammation,and glutamatergic excitotoxicity have previously been implicated in both secondary brain injury and *** particular,reactive oxygen species appear to be key in mediating molecular insult in neuroinflammation and *** such,it is likely that post injury oxidative stress is a key mechanism which links traumatic brain injury to increased risk of ***,reactive oxygen species and their subsequent byproducts may serve as novel fluid markers for identification and monitoring of cellular ***,these reactive species may further serve as a suitable therapeutic target to reduce the risk of post-injury neurodegeneration and provide long term quality of life improvements for those suffering from traumatic brain injury.

关键词： Traumatic brain injury Neurodegenerative diseases Alzheimer’s disease Parkinson’s disease Amyotrophic lateral sclerosis Oxidative stress Reactive oxygen species

Primary prevention of colorectal cancer:Myth or reality?

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World Journal of Gastroenterology 2014年第41期20卷 15060-15069页

作者： marcela Crosara Teixeira Maria Ignez Braghiroli Jorge Sabbaga Paulo M Hoff Division of Medical Oncology Instituto do Cancer do Estado de S?o PauloHospital Sírio Libanês

Colorectal cancer incidence has been rising strongly in parallel with economic *** the past few decades,much has been learned about the lifestyle,dietary and medication risk factors for this *** respect to lifestyle,compelling evidence indicates that prevention of weight gain and maintenance of a reasonable level of physical activity can positively influence in lowering the *** there is controversy about the role of specific nutritional factors,consideration of dietary pattern as a whole appears useful for formulating *** quite often recommended,the role for many supplements,including omega-3,vitamin D,folate,and vitamin B6,remains *** calcium and vitamin D supplementation appear to add a modest benefit,particularly in those with a low daily *** regard to chemoprevention,medications such as aspirin and nonsteroidal antiinflammatory drugs,and postmenopausal hormonal replacement for women might be associated with substantial reductions in colorectal cancer risk,though their utility is affected by their side effect ***,the role of agents such as statins,bisphosphonates and antioxidants have yet to be ***,primary prevention strategies focusing on modifying environmental,lifestyle risk factors,and chemopreventive drugs are options that have already been tested,and may impact on colon cancer incidence.

关键词： Primary prevention Colorectal cancer Physical activity Diet Chemoprevention

Biological performance of particleboard incorporated with boron minerals

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Journal of Forestry Research 2017年第1期28卷 195-203页

作者： Evren Terzi S.Nami Kartal Philippe Gerardin Claudia marcela Ibanez Tsuyoshi Yoshimura Department of Forest Biology and Wood Protection Technology Faculty of ForestryIstanbul University34473 BahcekoyIstanbulTurkey Faculte des Sciences et Technologies Universite de Lorraine54506 Vandoeuvre-les-Nancy CedexFrance Unidad Academica de Gestion Tecnologica Departamento TecnologicoFacultad de QuimicaUniversidad de la Republica UruguayMontevideoUruguay Laboratory of Innovative Humano-Habitability Research Institute for Sustainable Humanosphere(RISH)Kyoto UniversityUjiKyoto 611-0011Japan

We compared resistance to decay, mold fungi, termites and insect larvae of particleboards incorporated with the raw boron minerals ulexite and colemanite to that of particleboards impregnated with the commercial boron preservative zinc borate, or boric acid plus a borax mixture. We also quantified water absorption, thickness swell and boron release of particleboards. Ulexite had the best decay resistance, and colemanite had the best termite resistance. However, ulexite and colemanite were not as effective as zinc borate or the boric acid/borax mixture in preventing mold growth. In general, the boric acid/borax mixture combination was more effective against Anobium larvae than the other treatments. Less boron was released by specimens containing zinc borate and colemanite than by those containing ulexite or the boric acid/borax mixture. In general, water absorption and thickness swell were similar among the different treatments, but both were slightly higher in the ulexite-incorporated specimens. Further mechanical tests will be needed to evaluate the particle- board properties and thereby the compatibility of these boron minerals with various manufacturing processes.

关键词： Biological resistance Borax Boric acid Colemanite Particleboard Ulexite

Anatomical, Histochemical and Cytogenetic Features of <i>Doryopteris triphylla</i>(Pteridaceae)

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American Journal of Plant Sciences 2017年第4期8卷 907-920页

作者： Diego Armando Neira Aldo Rubén Andrada Valeria de los ángeles Páez Ana María Rodriguez Norma Fabiana Ríos Olga Gladys martínez marcela Alicia Hernández Herbario Pteridológico Fundación Miguel Lillo Tucumán Argentina Instituto de Genética Fundación Miguel Lillo Tucumán Argentina Inquinoa-Conicet Tucumán Argentina Facultad de Ciencias Naturales Universidad Nacional de Salta-IBIGEO Salta Argentina

Doryopteris triphylla (Pteridaceae-Cheilanthoideae) grows in xeric habitats in Brazil, Paraguay, Uruguay and Argentina. The aim of this study was to characterize D. triphylla anatomically, histochemically and cytogenetically. For anatomical characterization, rhizomes, roots, petioles and leaves were made and then stained using Safranine-Astra Blue for further observations. Leaf blades were also cleared. For histochemical analysis, leaf cross sections were stained with different reagents to identify glandular trichomes compounds. For cytogenetic characterization, a karyogram was performed using laboratory cultivated roots. Results show a dictyostelic rhizome covered with scales with apical secreting gland;diarch roots;petiole cross-sections show thick cuticle, uniseriate epidermis, parenchymatic cortex cells with thick walls and a vascular bundle with two xylem groups;and hypostomatic fronds with glandular trichomes. Histochemical studies of secretion products of the glandular trichomes were positive for polysaccharides, pectins, lipids, acid lipids, dihydroxyphenols, phenols and flavonoids. Cytogenetically, D. triphylla is described as a diploid species (2n = 60), with chromosomes gradually decreasing in size. The apical glands in scales of rhizomes, the presence of two xylem groups in the vascular bundle in the petiole and the glandular trichomes on the abaxial surface are new contributions to the species. The type of chemical products secreted by glandular leaf trichomes and karyotype estimation is shown for the first time in this species.

关键词： Anatomy Histochemistry Karyogram Pteridaceae

Friction Sensitivity of Nitramines. Part Ⅳ:Links to Surface Electrostatic Potentials

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含能材料 2011年第6期19卷 613-615页

作者： Zdeněk Friedl marcela Jungová Svatopluk Zeman Adéla Husarová Faculty of Chemistry Brno University of TechnologyCZ-612 00 BrnoThe Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCZ-532 10 PardubiceThe Czech Republic

The friction sensitivity(FS) of five aliphatic linear and eight cyclic nitramines has been determined and correlated with DFT B3LYP/6-31-G(d,p) // 6-311+G(d,p) positive(VS,max) and negative(VS,min) extremes of molecular surface electrostatic potentials VS(r).While there is an ambiguous relationship between the VS,max values and FS values,the decrease of FS is connected(more or less) with increase in VS,min values.

关键词： physical chemistry electrostatic potential friction nitramines sensitivity

Human papilloma virus and esophageal carcinoma in a Latin-American region

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World Journal of Gastroenterology 2009年第25期15卷 3142-3147页

作者： Roberto Herrera-Goepfert marcela Lizano Suminori Akiba Adela Carrillo-García Mauricio Becker-D'Acosta Department of Pathology National Cancer Institute Unit of Biomedical Research in Cancer National Cancer Institute and Biomedical Research InstituteNational Autonomous University of Mexico Department of Epidemiology and Preventive Medicine Kagoshima University Graduate School of Medical and Dental Sciences

AIM:To investigate the presence of high-risk human papilloma virus (HPV) in esophageal squamous cell carcinomas (ESCCs) in a non-selected Mexican ***: Cases with a pathological diagnosis of squamous cell carcinoma of the esophagus were obtained from Department of Pathology files, at the National Cancer Institute in Mexico City during the period between 2000 and 2008. Slides from each case were reviewed and cases with sufficient neoplastic tissue were selected for molecular analysis. DNA was extracted from paraffin-embedded tissue samples for polymerase chain reaction analysis to detect HPV DNA sequences. Demographic and clinical data of each patient were retrieved from corresponding clinical ***: HPV was detected in 15 (25%) of ESCCs. HPV-16 was the most frequently observed genotype, followed by HPV-18; HPV-59 was also detected in one case. Unfortunately, HPV genotype could not be established in three cases due to lack of material for direct sequencing, although universal primers detected the presence of HPV generic sequences. No low-risk HPV genotypes were found nor was HPV-16/18 co-infection. HPV presence in ESCC was not significantly associated with gender, age, alcohol consumption, smoking, anatomic location, or histologic grade. All patients belonged to low and very low socioeconomic strata, and were diagnosed at advanced disease stage. Male patients were most commonly affected and the male:female ratio in HPV-positive ESCC increased two- fold in comparison with HPV-negative cases (6.5:1 vs 3.1:1).CONCLUSION: High prevalence of high-risk HPV in ESCC in Mexico does not support the hypothesis that HPV-associated ESCC is more common in areas with higher ESCC incidence rates.

关键词： Esophagus Squamous cell carcinoma virusHuman papilloma virus High-risk human papilloma virus

A Th2-score in the tumor microenvironment as a predictive biomarker of response to Bacillus Calmette Guérin in patients with non-muscle invasive bladder carcinoma:A retrospective study

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Oncology Research 2023年第2期31卷 207-220页

作者： GUSTAVO martÍN VILLOLDO MARÍA TERESA POMBO MARIANA ARIS JOAQUÍN CHEMI PABLO MANDÓ SUPRIYA NAGARAJU JUAN CAMEAN ADRIÁN BURIONI DEBORAH EGEA MORA AMAT JOSÉLEÓN MELLADO JOSÉMORDOH ALBERTO VILLARONGA MARÍA marcela BARRIO Urology Department Instituto Alexander FlemingCiudad Autónoma de Buenos Aires1426Argentina Immunohistochemistry Department Instituto Alexander FlemingCiudad Autónoma de Buenos Aires1426Argentina Centro de Investigaciones Oncológicas Fundación Cáncer FUCACiudad Autónoma de Buenos Aires1426Argentina Urology Department MD Anderson Cancer CenterHoustonTX77030USA Pathology Department Instituto Alexander FlemingCiudad Autónoma de Buenos Aires1426Argentina

Intravesical Bacillus Calmette Guerin(BCG)is the gold standard therapy for intermediate/high-risk nonmuscle invasive bladder cancer(NMIBC).However,the response rate is~60%,and 50%of non-responders will progress to muscle-invasive *** induces massive local infiltration of inflammatory cells(Th1)and ultimately cytotoxic tumor *** searched for predictive biomarker of BCG response by analyzing tumor-infiltrating lymphocyte(TIL)polarization in the tumor microenvironment(TME)in pre-treatment ***-treatment biopsies from patients with NMIBC who received adequate intravesical instillation of BCG(n=32)were evaluated retrospectively by *** polarization was assessed by quantifying the T-Bet+(Th1)and GATA-3+(Th2)lymphocyte ratio(G/T),and the density and degranulation of EPX+*** addition,PD-1/PD-L1 staining was *** results correlated with BCG *** most non-responders,Th1/Th2 markers were compared in pre-and post-BCG *** was 65.6%in the study *** responders had a higher G/T ratio and a greater number of degranulated EPX+*** combined into a Th2-score showed a significant association with higher scores in responders(p=0.027).A Th2-score cut-off value>48.1 allowed discrimination of responders with 91%sensitivity but lower ***-free survival was significantly associated with the Th2-score(p=0.007).In post-BCG biopsies from recurring patients,TILs increased Th2-polarization,probably reflecting BCG failure to induce a pro-inflammatory status and,thus,a lack of ***-L1/PD-1 expression was not associated with the response to *** results support the hypothesis that a preexisting Th2-polarized TME predicts a better response to BCG,assuming a reversion to Th1 polarization and antitumor activity.

关键词： Non-muscle invasive bladder cancer BCG predictive biomarkers Lymphocyte polarization