Semiclassical Nonlinear Approach for Mesoscopic Circuit

Based on energy conservation considerations we study the nonlinear dynamic behavior of a quantum mesoscopic circuit, which is characterized through parameters of inductance and capacitance. Nonlinearity is given by the initial conditions of magnetic flux and discreteness charge which oscillate in the interval [- , + ], being the magnetic flux normalized by . This LC circuit with quantized electric charge is excited by energy battery that can produce an electrical discreteness charge on the capacitor. The dynamics of the mesoscopic circuit is highly nonlinear. Our results show for the magnetic flux a nearly square wave with an elongated period when compared with the linear case and a train of narrow pulses for the discrete charge

A Seismic Channel Model: The San Ramon Fault

Although seismic waves have been studied for many years, their soliton structure has only recently studied. Deformation solitons propagate along earthquake faults and can induce large earthquakes. Rotation solitons are generated in earthquake sources and propagate throughout the Earth. The conclusion to be reached from our paper is that the research on seismic solitons is essential for investigating the propagation of seismic waves and helps understand mechanisms triggering earthquakes. This paper discusses the development of elastodynamics equations similar to Maxwell's equations in a chiral -mode which is applied to a seismic channel, which is dispersive and nonlinear. The chirality is described in terms of the formalism proposed by Born-Fedorov. The nonlinearity is Kerr-type, and dispersion of the medium is taken into account explicitly through the Taylor series expansion. Through numerical calculations these theoretical results allow us analyze the soliton propagation of S-seismic pulses which can induce strong earthquakes. The numerical calculation is applied to the San Ramon Fault localized in Santiago City, Chile which is a seismically active fault that is a main element to be considered in any study on seismic hazard assessment for this city

Diazoxide-responsive hyperinsulinemic hypoglycemia caused by HNF4A gene mutations

Objective: The phenotype associated with heterozygous HNF4A gene mutations has recently been extended to include diazoxide responsive neonatal hypoglycemia in addition to maturity-onset diabetes of the young (MODY). To date, mutation screening has been limited to patients with a family history consistent with MODY. In this study, we investigated the prevalence of HNF4A mutations in a large cohort of patients with diazoxide responsive hyperinsulinemic hypoglycemia (HH). Subjects and methods: We sequenced the ABCC8, KCNJ11, GCK, GLUD1, and/or HNF4A genes in 220 patients with HH responsive to diazoxide. The order of genetic testing was dependent upon the clinical phenotype. Results: A genetic diagnosis was possible for 59/220 (27%) patients. KATP channel mutations were most common (15%) followed by GLUD1 mutations causing hyperinsulinism with hyperammonemia (5.9%), and HNF4A mutations (5%). Seven of the 11 probands with a heterozygous HNF4A mutation did not have a parent affected with diabetes, and four de novo mutations were confirmed. These patients were diagnosed with HI within the first week of life (median age 1 day), and they had increased birth weight (median +2.4 SDS). The duration of diazoxide treatment ranged from 3 months to ongoing at 8 years. Conclusions: In this large series, HNF4A mutations are the third most common cause of diazoxide responsive HH. We recommend that HNF4A sequencing is considered in all patients with diazoxide responsive HH diagnosed in the first week of life irrespective of a family history of diabetes, once KATP channel mutations have been excluded

Low genetic diversity associated with low prevalence of Anaplasma marginale in water buffaloes in Marajó Island, Brazil

The rickettsia Anaplasma marginale is the etiologic agent of bovine anaplasmosis, an important tick-borne disease affecting cattle in tropical and subtropical regions of the world. In endemic regions, the genetic diversity of this pathogen is usually related to the high prevalence of the disease in cattle. The major surface protein 1 alpha (MSP1a) has been used as a marker to characterize the genetic diversity and for geographical identification of A. marginale strains. The present study reports the characterization of A. marginale MSP1a diversity in water buffaloes. Blood samples were collected from 200 water buffaloes on Marajó Island, Brazil where the largest buffalo herd is located in the Western hemisphere. Fifteen buffaloes (7.5%) were positive for A. marginale msp1α by PCR. Four different strains of A. marginale with MSP1a tandem repeat structures (4-63-27), (162-63-27), (78-24-24-25-31) and (τ-10-10-15) were found, being (4-63-27) the most common. MSP1a tandem repeats composition in buffalos and phylogenetic analysis using msp1α gene showed that the A. marginale strains identified in buffaloes are closely related to A. marginale strains from cattle. The results demonstrated low genetic diversity of A. marginale associated with low bacterial prevalence in buffaloes and suggested that buffaloes may be reservoirs of this pathogen for cattle living in the same area. The results also suggested that mechanical transmission and not biological transmission by ticks might be playing the major role for pathogen circulation among water buffaloes in Marajó Island, Brazil.We thank the Coordination for the Improvement of Higher Education Personnel (CAPES) foundation and the National Council for Technological and Scientific Development (CNPq) for their financial support.Peer Reviewe

Plantas de cobertura de solo para sistema plantio direto.

A camada de palha, sobre o solo, e essencial para o sucesso do Sistema Plantio Direto (SPD). Cria um ambiente extremamente favoravel as condicoes fisicas, quimicas e biologicas do solo contribuindo para o controle de plantas daninhas, estabilizacao da producao e recuperacao ou manutencao da qualidade do solo. O sistema de rotacao e sucessao de culturas deve ser adequado para permitir a manutencao de uma cobertura minima do solo com palha. Na escolha destas plantas, e fator decisivo conhecer a sua adaptacao a regiao e sua habilidade em crescer num ambiente menos favoravel, uma vez que as culturas comerciais sao estabelecidas nas epocas mais propicias. Isto e especialmente verdade nas condicoes de Brasil Central, onde o inverno e seco, ao passo que na regiao Sul, de inverno umido, nao existe essa limitacao e ha maior opcao de plantas adaptadas as condicoes do inverno. Existem muitas plantas de cobertura para as diferentes regioes edafoclimaticas do Brasil, e a experiencia local e decisiva nesta selecao. Em qualquer situacao, deve-se ter sempre em mente que nao existe uma planta milagrosa e que o ideal e ter mais de uma dessas especies no sistema de producao, onde busca-se aliar renda a preservacao ambiental

Comparison of 30 THz impulsive burst time development to microwaves, H-alpha, EUV, and GOES soft X-rays

The recent discovery of impulsive solar burst emission in the 30 THz band is raising new interpretation challenges. One event associated with a GOES M2 class flare has been observed simultaneously in microwaves, H-alpha, EUV, and soft X-ray bands. Although these new observations confirm some features found in the two prior known events, they exhibit time profile structure discrepancies between 30 THz, microwaves, and hard X-rays (as inferred from the Neupert effect). These results suggest a more complex relationship between 30 THz emission and radiation produced at other wavelength ranges. The multiple frequency emissions in the impulsive phase are likely to be produced at a common flaring site lower in the chromosphere. The 30 THz burst emission may be either part of a nonthermal radiation mechanism or due to the rapid thermal response to a beam of high-energy particles bombarding the dense solar atmosphere.Comment: accepted to Astronomy and Astrophysic

Educación cimarrona

La presente obra consta de tres partes bien definidas: la primera expone el resultado de los talleres y el trabajo de las coordinadoras de los Centros de Educación Cimarrona de los siguientes barrios de Sucumbíos: El Cisne, Amazonas, San Valentín y la parroquia Pacayacu, y recupera historias de viada de hombres y mujeres así como la tradición oral presente en su memoria colectiva y recuperada por el grupo de trabajo. La segunda parte consta de las reflexiones teóricas sobre el cimarronaje y los fundamentos conceptuales que inspiran los Centros de Educación Cimarrona. La tercera y última sección ofrece, en primer lugar, el relato reflexivo de los talleres de grafoplástica identitaria y, luego, una guía para niños investigadores al servicio de la revitalización de la cultura, las identidades y las memorias vivas de los pueblos cimarrone