Sc substitution for Mg in MgB2: effects on Tc and Kohn anomaly

Here we report synthesis and characterization of Mg_{1-x}Sc_{x}B_{2} (0.12T_{c}>6 K. We find that the Sc doping moves the chemical potential through the 2D/3D electronic topological transition (ETT) in the sigma band where the ``shape resonance" of interband pairing occurs. In the 3D regime beyond the ETT we observe a hardening of the E_{2g} Raman mode with a significant line-width narrowing due to suppression of the Kohn anomaly over the range 0<q<2k_{F}.Comment: 8 pages, 4 EPS figures, to be published in Phys. Rev.

Homogenization and free-vibration analysis of elastic metamaterial plates by Carrera Unified Formulation finite elements

This work focuses on the assessment of a novel so-called “homogenization method” allowing to transform a heterogeneous material with inclusions or holes into an equivalent homogeneous material with equal mechanical behavior. The aim is to avoid meshing holes of the real material in finite-element codes, thus improving computation time for further analysis of the material. Typical periodic structure of passive acoustic metamaterial plates is considered here, with inclusions/holes that should improve the acoustic performances in the low-frequency range. The three-dimensional homogenization method, based on Carrera unified formulation (CUF) [E. Carrera, M. Cinefra, M. Petrolo, and E. Zappino. Finite Element Analysis of Structures through Unified Formulation. John Wiley & Sons, 2014] and Mechanics of Structure Genome, is assessed for a perforated plate made of a linear elastic material with periodic arrangement of holes. Different configurations of the metamaterial plate are considered, changing the number of the holes. The results obtained from the free-vibration analysis of the homogenized plates, performed by higher-order two-dimensional models contained in CUF, are compared with ABAQUS results and both numerical and experimental results provided in literature

Avaliação da incidência de brusone em arroz (Oryza sativa L.) de terras altas sob cultivo com diferentes dosagens de agrosilício e rotação de cultura com soja (Glycine max (L.) Merrill) em sistema de plantio direto.

O Brasil é o oitavo produtor mundial de arroz. No Maranhão, o arroz é cultivado em consórcio com outras culturas, destacando-se o feijão e o milho, sendo pouco frequente o cultivo isolado. A cultura do arroz é afetada por diversos fatores, sendo as doenças fúngicas uma das principais responsáveis pela perda da produtividade. No entanto o agrosilício (silicato de cálcio, magnésio e silício) tem sido testado em diversos experimentos, pois o silício aumenta a resistência da planta. O presente trabalho objetivou analisar a resposta da planta ao agrosilício, considerando a incidência de doenças e estabelecer a dose mais eficiente de silicato de cálcio e magnésio para compor o manejo integrado de doenças do arroz, no estado do Maranhão. O experimento foi instalado nas dependências do Parque de Exposição de Imperatriz-MA, pertencente ao Sindicato Rural de Imperatriz, situado a BR 010, em uma área cultivada no ano anterior com soja (Glycine max (L.) Merrill). Em delineamento de blocos ao caso com parcelas subdivididas e quatro repetições, os cinco tratamentos são compostos pelas doses de silício (0, 1, 2, 4, 8 t/ha de silicato de cálcio e magnésio - Agrosilício). De acordo com os dados das análises estatísticas não houve diferença significativa entre nenhuma das dosagens de silício aplicadas para o controle das doenças: brusone nas folhas, brusone nas panículas, sendo necessária a condução de novos experimentos para indicar-se a melhor dosagem de agrosilício a ser aplicada ao solo para redução das doenças do arroz

Caracterização da virulência de Magnaporthe grisea em cultivares diferenciadoras japonesas e linhas quase-isogênicas das cultivares IAC-25 e de CO-39 de arroz.

O objetivo do presente trabalho foi caracterizar a virulência de populações de M. grisea provenientes das cultivares BRS Bonança e Primavera, utilizando as diferenciadoras japonesas e as NIL's das cultivares CO-39 e IAC-25

Periodicity and quasi-periodicity effects on vibration band gaps

PERIODICITY AND QUASI-PERIODICITY EFFECTS ON VIBRATION BAND GAPS: NUMERICAL INVESTIGATIONS ON ONE-DIMENSIONAL STRUCTURE

Supressão de brusone foliar em arroz com o uso de Epicoccum sp.

O objetivo do trabalho foi estudar o processo de indução com a pulverização do concentrado de Epicoccum sp. a 4 mg.mL-1 em plantas de arroz, 48 horas antes da inoculação desafiadora com M. oryzae.Apresentação oral - Pós-graduação

Global-local plug-in for high-fidelity composite stress analysis in ABAQUS

This paper introduces a user-friendly tool for accurate stress prediction in laminate shell models in ABAQUS. The aim is to provide users with a code for the fast computation of three-dimensional solutions that overcome the limitations of classical shell models and facilitate the use of advanced composite failure criteria consistently. The methodology is based on a two-step global/local technique, denoted to as element-wise (EW), in which accurate local models with 3D capabilities stem from individual shell elements. The local analysis exploits refined laminated theories accounting for layer-wise deformations. Numerical examples on a typical aircraft structure serve as assessments to show the tool capabilities in handling various failure mode onsets., e.g., fiber breakage and matrix cracking

Response and toxicity to cytarabine therapy in leukemia and lymphoma: From dose puzzle to pharmacogenomic biomarkers

Cytarabine is a pyrimidine nucleoside analog, commonly used in multiagent chemotherapy regimens for the treatment of leukemia and lymphoma, as well as for neoplastic meningitis. Ara‐C‐based chemotherapy regimens can induce a suboptimal clinical outcome in a fraction of patients. Several studies suggest that the individual variability in clinical response to Leukemia & Lymphoma treatments among patients, underlying either Ara‐C mechanism resistance or toxicity, appears to be associated with the intracellular accumulation and retention of Ara‐CTP due to genetic variants related to metabolic enzymes. Herein, we reported (a) the latest Pharmacogenomics biomarkers associated with the response to cytarabine and (b) the new drug formulations with optimized pharmacokinetics. The purpose of this review is to provide readers with detailed and comprehensive information on the effects of Ara‐C‐based therapies, from biological to clinical practice, maintaining high the interest of both researcher and clinical hematologist. This review could help clinicians in predicting the response to cytarabine‐based treatments

Effect of the combined treatment with 5-fluorouracil, γ-interferon or folinic acid on carcinoembryonic antigen expression in colon cancer cells

5-Fluorouracil (5-FU) and human recombinant γ-interferon (γ-IFN) were found to increase the expression of carcinoembryonic antigen (CEA) in human cancer cells in vitro. In the present study, the antimetabolite was associated with γ-IFN or folinic acid (FA), a biochemical modulator of cellular metabolism of 5.FU, able to increase its antineoplastic activity. Treatment of two human colon cancer cell lines (HT-29 and WiDr) with 5-FU + γ-IFN resulted in an increase of CEA expression higher than that obtainable with both agents alone, although no synergistic effects were obtained. This was demonstrated in terms of: (a) mRNA transcripts (HT-29); (b) cytoplasm and membrane CEA protein levels detected by Western blot analysis (HT-29); and (c) plasma membrane reactivity determined by flow cytometry analysis (HT-29 and WiDr). Moreover, 5-FU + γ-IFN increased HLA class I molecules in the HT- 29 cell membrane over that obtainable with γ-IFN alone. In contrast, both agents did not induce the expression of the costimulatory molecule B7-1. Treatment with FA enhanced the antitumor effect of 5-FU but not its ability to augment CEA expression. This suggests that the FA-sensitive biochemical mechanism of action of 5-FU is not involved in its effect on CEA expression. In vivo studies showed, for the first time, that 5-FU, alone or combined with γ-IFN, increases the amount of CEA protein over controls, either in cancer cells or in peripheral blood of nude mice bearing HT-29 cells. These results could be of potential diagnostic and/or therapeutic value when CEA protein is the target of humoral or cell-mediated immunity