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An overview on nucleation theories and models

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Journal of Rare Earths 2019年第10期37卷 1015-1022页

作者： marcos Flavio de Campos jose Adilson de Castro Department of Mechanical Engineering Federal Fluminense University

Several different models for coercivity are discussed. There are two main situations: i) nanocrystalline magnets, with grain size bellow the single domain particle size, and ii) magnets with grain size above single domain particle size. The described theories and models are general, and can be applied in either NdFeB magnets, SmFeCoCuZr or strontium ferrite magnets. The spring effect observed in isotropic nanocrystalline magnets can be explained with the Stoner-Wohlfarth model. Modifications of the StonerWohlfarth model are necessary to take into account the effect of interaction between grains. When the grain size is above the single domain size, energy considerations show that nucleation should occur at the surface of grains. Nucleation is interpreted as a two-step process, where domain wall displacement occurs for grain size above single domain size, after a nucleus is first formed. The effect of grain size on the coercive field is discussed.

关键词： Coercivity Nucleation Grain size Spring effect Nd-Fe-B Permanent magnet

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Genetic and epigenetic control of transfer cell development in plants

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Journal of Genetics and Genomics 2016年第9期43卷 533-539页

作者： Jing Yuan Perry Bateman jose Gutierrez-marcos State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences School of Life Sciences University of Warwick

The inter-cellular translocation of nutrients in plant is mediated by highly specialized transfer cells （TCs）. TCs share similar functional and structural features across a wide range of plant species, including location at plant exchange surfaces, rich in secondary wall ingrowths, facilitation of nutrient flow, and passage of select molecules. The fate of endosperm TCs is determined in the TC fate acquisition stage （TCF）, before the structure features are formed in the TC differentiation stage （TCD）. At present, the molecular basis of TC development in plants remains largely unknown. In this review, we summarize the important roles of the signaling molecules in different development phases, such as sugars in TCF and phytohormones in TCD, and discuss the genetic and epigenetic factors, including TC-specific genes and endogenous plant peptides, and their crosstalk with these signaling molecules as a complex regulatory network in regulation of TC develonment in olants.

关键词： Transfer cells Differentiation Signals and genes network

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Effects of obstructive sleep apnea and its treatment over the erectile function： a systematic review

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Asian Journal of Andrology 2017年第3期19卷 303-310页

作者： Felix Campos-Juanatey marcos Fernandez-Barriales Monica Gonzalez jose A Portillo-Martin Urology Department Marques de Valdecilla University Hospital Santander 39008 Spain Institute of Investigation Marques de Valdecilla Santander 39011 Spain Oral and Maxillofacial Surgery Department Araba University Hospital Araba 01004 Spain Sleep and Ventilation Unit Marques de Valdecilla University Hospital Santander 39008 Spain Medical and Surgical Sciences Department School of Medicine University of Cantabria Santander 39011 Spain.

Erectile dysfunction （ED） is considered a condition with a broad range of etiologies. Obstructive sleep apnea （OSA） syndrome is one of the lesser studied risk factors for ED. We intend to summarize the current evidence on the relationship between OSA and sexual impairment, focusing on the results in terms of erectile function of the different therapies offered to OSA patients. A systematic review was conducted, selecting articles related to the physiology of OSA and ED, and to the treatments of OSA syndrome and their reported outcomes in erectile and sexual function. Higher prevalences of ED in the OSA groups have been published. However, whether this effect on the erectile function occurs in the entire range of OSA severities remains unclear. Several hypotheses were proposed to explain the physiology of this association. Continuous Positive Airway Pressure as a treatment for OSA patients with ED has achieved a significative improvement in the sexual parameters in most of the studies. Phosphodiesterase type 5 inhibitors （iPDE5） on demand are useful as a treatment for ED in this subgroup of patients, with high satisfaction rates. The surgical treatment for the OSA evidenced benefits over the erectile function, and the effect on the sexual satisfaction of the therapy using Mandibular Advancement Devices is still undefined.

关键词： continuous positive airway pressure erectile dysfunction obstructive sleep apnea operative surgical procedures phosphodiesterase type 5 inhibitors

A comprehensive review of genetic causes of obesity

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World Journal of Pediatrics 2024年第1期20卷 26-39页

作者： Marcio jose Concepcion-Zavaleta Juan Eduardo Quiroz-Aldave Maria del Carmen Durand-Vasquez Elman Rolando Gamarra-Osorio Juan del Carmen Valencia de la Cruz Claudia Mercedes Barrueto-Callirgos Susan Luciana Puelles-Leon Elena de Jesus Alvarado-Leon Frans Leiva-Cabrera Francisca Elena Zavaleta-Gutierrez Luis Alberto Concepcion-Urteaga jose Paz-Ibarra Universidad Cientifica del Sur Bolivar 2150 AvenuePueblo Libre15084LimaPeru Division of Medicine Hospital de Apoyo ChepénChepenPeru Division of Family Medicine Hospital de Apoyo ChepénChepenPeru Division of Endocrinology Hospital Victor Lazarte EchegarayTrujilloPeru Division of Pediatrics Hospital de Apoyo ChepenChepenPeru Division of Internal Medicine Hospital de Apoyo ChepenChepenPeru Division of Genetics Universidad Nacional de TrujilloTrujilloPeru Division of Neonatology Hospital Belen de TrujilloTrujilloPeru Division of Internal Medicine Universidad Nacional de TrujilloTrujilloPeru Department of Medicine School of MedicineUniversidad Nacional Mayor de San MarcosLimaPeru

Background Obesity is a multifactorial chronic disease with a high,increasing worldwide *** causes account for 7%of the cases in children with extreme *** sources This narrative review was conducted by searching for papers published in the PubMed/MEDLINE,Embase and SciELO databases and included 161 *** search used the following search terms:"obesity","obesity and genetics","leptin","Prader-Willi syndrome",and"melanocortins".The types of studies included were systematic reviews,clinical trials,prospective cohort studies,cross-sectional and prospective studies,narrative reviews,and case *** The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body ***,several important aspects of the pathophysiology of obesity remain *** causes of obesity can be grouped into syndromic,monogenic,and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years,hyperphagia,or a family history of extreme obesity.A microarray study,an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this *** are three therapeutic levels:lifestyle modifications,pharmacological treatment,and bariatric *** Genetic study technologies are in constant development;however,we are still far from having a personalized approach to genetic causes of obesity.A significant proportion of the affected individuals are associated with genetic causes;however,there are still barriers to its approach,as it continues to be underdiagnosed.

关键词： Leptin Melanocortin Obesity Prader-Willi syndrome Precision medicine

Contrasting levels of genotype by environment interaction for life history and morphological traits in invasive populations of Zaprionus indianus(Diptera:Drosophilidae)

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Insect Science 2020年第5期27卷 1090-1100页

作者： Nicolas J.Lavagnino marcos Imberti Victoria E.Ortizj Nicolas Flaibani Juan jose Fanara Laboratorio de Evolucion Departamento de EcologiaGenetica y EvolucidnFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina IEGEBA-CONICET Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina

It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during *** indianus Gupta(Diptera:Drosophilidae)is an Afrotropical invasive fly species introduced to the South American continent in *** species is generalist and polyphagous,since it develops and feeds in several different fruit *** characteristics of *** suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion *** this sense,our aim was to investigate the role of genetic variation for phenotypic plasticity(geno-type by environment interaction)in *** invasion of the South American ***,we quantified quantitative genetic variation and genotype by environment in-teractions of morphological and life history traits in different developmental environments,that is,host *** was done in different populations in the invasive range of ***-anus in *** showed that *** populations have considerable amounts of quantitative genetic ***,genotype by environment interactions was detected for the different traits analyzed in response to the different developmental ***,the amounts and patterns of these parameters differed between *** interpreled these results as the existence of diferences in evolutionary potential be-tween populations that have an important role in the short-and long-term success of the *** invasion process.

关键词： biological invasion genotype by env ironment interaction invaded range life history traits morphological traits Zaprionus indianus

The lncRNA MARS modulates the epigenetic reprogramming of the marneral cluster in response to ABA

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Molecular Plant 2022年第5期15卷 840-856页

作者： Thomas Roulé Aurelie Christ Nosheen Hussain Ying Huang Caroline Hartmann Moussa Benhamed jose Gutierrez-marcos Federico Ariel Martin Crespi Thomas Blein UniversitéParis-Saclay CNRSINRAEUniversitéEvryInstitute of Plant Sciences Paris-Saclay(IPS2)91190 Gif-sur-YvetteFrance Universitéde Paris Institute of Plant Sciences Paris-Saclay(IPS2)91190 Gif-sur-YvetteFrance Instituto de Agrobiotecnología del Litoral CONICETFBCBUniversidad Nacional del LitoralColectora Ruta Nacional 168 km 03000 Santa FeArgentina School of Life Sciences University of WarwickCoventry CV47ALUK

Clustered organization of biosynthetic non-homologous genes is emerging as a characteristic feature of plant *** co-regulation of clustered genes seems to largely depend on epigenetic reprogram-ming and three-dimensional chromatin *** this study,we identified the long non-coding RNA(lncRNA)MARneral Silencing(MARS),localized inside the Arabidopsis marneral cluster,which con-trols the local epigenetic activation of its surrounding region in response to abscisic acid(ABA).MARS modulates the POLYCOMB REPRESSIVE COMPLEX 1(PRC1)component LIKE HETEROCHROMATIN PROTEIN 1(LHP1)binding throughout the cluster in a dose-dependent manner,determining H3K27me3 deposition and chromatin *** response to ABA,MARS decoys LHP1 away from the cluster and promotes the formation of a chromatin loop bringing together the MARNERAL SYNTHASE 1(MRN1)locus and a distal ABA-responsive *** enrichment of co-regulated lncRNAs in clustered meta-bolic genes in Arabidopsis suggests that the acquisition of novel non-coding transcriptional units may constitute an additional regulatory layer driving the evolution of biosynthetic pathways.

关键词： lncRNA enhancer cluster chromatin conformation LHP1 ABA seed germination epigenetics marneral

A SIMPLE DEVICE TO MONITOR SEDIMENT YIELD FROM GULLY EROSION

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International Journal of Sediment Research 2005年第3期20卷 90-94页

作者： Antonio jose Teixeira GUERRA,marcos FIGUEIREDO Senior Lecturer in Physical Geography Federal University of Rio de Janeiro Av. Canal de Marapendi 1100 apto. 608 Bloco 2 Barra da Tijuca-CEP Rio de Janeiro Rio de Janeiro 22.631-050 Brazil Lecturer in Physical Geography State University of Mato Grosso

The focus of this paper is the design and use of a simple device to determine sediment yield from gullies. The simplicity and low cost makes this device especially useful when resources are limited. In this study, it was used to measure sediment yield at a site called An?o Gully, in a study area in Cáceres municipality (15o 57’ S and 57o 31’ W, Mato Grosso State, Brazil). This gully is located 28 kilometres from the center of the town, Cáceres, and was easy to reach during and immediately after storm events to make measurements with this device.

关键词： Gully erosion Sediment yield Gully monitoring Simple device

Chemical composition of Rosmarinus officinalis essential oil and antioxidant action against gastric damage induced by absolute ethanol in the rat

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 677-681页

作者： Christiane Takayama Felipe Meira de-Faria Ana Cristina Alves de Almeida Ricardo jose Dunder Luis Paulo Manzo Eduardo Augusto Rabelo Socca Leonia Maria Batista marcos jose sal.ador Alba Regina Monteiro Souza-Brito Anderson Luiz-Ferreira Functional and Structural Biology Department Biology Institute Campinas State University Pharmacology Department Faculty of Medical Sciences Campinas State University Department of Pharmaceutical Sciences Federal University of Paraiba Plant Physiology Department Biology Institute Campinas State University Federal University of Goias Institute of Biotechnology Nucleus of Biological Sciences Regional Catalao

Objective: To evaluate the antioxidant activity of the essential oil obtained from Rosmarinus officinalis(R. officinalis) in ethanol-induced gastric ulcer model in ***: The antioxidant properties of the essential oil obtained from R. officinalis were evaluated against gastric injury induced by absolute ethanol. Gastric tissues were prepared to enzymatic assays. The levels of glutathione, lipid peroxides, and the activities of glutathione peroxidase, superoxide dismutase and myeloperoxidase were ***: Ethanol produced severe hemorrhagic lesions in the stomach with ulcerative lesion of(140.2 ± 37.2) mm2. In animals pretreated with essential oil of R. officinalis(50 mg/kg, p.o.), a significant inhibition of mucosal injury of(21.2 ± 7.1) mm2(84%inhibition) was observed. The essential oil of R. officinalis protected the gastric mucosa probably by modulating the activities of the enzymes(superoxide dismutase and glutathione peroxidase) and increasing or maintaining the levels of glutathione. In addition,lipid peroxides levels were reduced. The essential oil of R. officinalis was analyzed by gas chromatography–mass spectrometer and the main constituents were cineole(28.5%),camphor(27.7%) and alpha-pinene(21.3%).Conclusions: We suggest that the monoterpenes present in the essential oil obtained from R. officinalis may be among the active principles responsible for the antioxidant activity shown by essential oil of R. officinalis.

关键词： Rosmarinus officinalis L. Antioxidant activity Gastric ulcer Antioxidant enzymes

Clinical and environmental isolates of Burkholderia pseudomallei from Brazil: Genotyping and detection of virulence gene

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Asian Pacific Journal of Tropical Medicine 2017年第10期10卷 945-951页

作者： Tereza de Jesus Pinheiro Gomes Bandeira Debora de Souza Collares Maia Castelo-Branco marcos Fabio Gadelha Rocha Rossana de Aguiar Cordeiro Crister jose Ocadaque Manoel de Araújo Neto Paiva Raimunda Samia Nogueira Brilhante jose Júlio Costa Sidrim Specialized Medical Mycology Center Postgraduate Program in Medical Microbiology Federal University of Ceará Christus School of Medicine Postgraduate Program in Veterinary Sciences State University of Ceará Federal Institute of Education Science and Technology of Ceará

Objective: To evaluate the genetic diversity of clinical and environmental isolates of Burkholderia pseudomallei(***) recovered in Ceara, Brazil, and screen these isolates for the presence of type three secretion system virulence ***: Nineteen *** isolates(9 from clinical cases and 10 from soils)were *** amplified polymorphic DNA was performed with primers OPQ-2, OPQ-4 and OPQ-16 to evaluate the genetic diversity, and type three secretion system gene was detected through polymerase chain ***: Random amplified polymorphic DNA showed a genetic relatedness of approximately 50% among the tested *** isolates, which were grouped into two clades, of which the biggest ones comprised 18/19 isolates for primer OPQ-2, and 17/19 isolates for primer *** OPQ-4 grouped the isolates into three clades comprising 1/19, 3/19 and 15/19 ***, type three secretion system gene was detected in all tested ***: This is an effort to type *** strains from Ceara, which is important for better understanding this pathogen, contributing for the epidemiological surveillance of melioidosis in this endemic region.

关键词： Burkholderia pseudomallei Melioidosis RAPD TTSS gene