Anisotropic scaling for 3D topological models.

A proposal to study topological models beyond the standard topological classification and that exhibit breakdown of Lorentz invariance is presented. The focus of the investigation relies on their anisotropic quantum critical behavior. We study anisotropic effects on three-dimensional (3D) topological models, computing their anisotropic correlation length critical exponent [Formula: see text] obtained from numerical calculations of the penetration length of the zero-energy surface states as a function of the distance to the topological quantum critical point. A generalized Weyl semimetal model with broken time-reversal symmetry is introduced and studied using a modified Dirac equation. An approach to characterize topological surface states in topological insulators when applied to Fermi arcs allows to capture the anisotropic critical exponent [Formula: see text]. We also consider the Hopf insulator model, for which the study of the topological surface states yields unusual values for [Formula: see text] and for the dynamic critical exponent z. From an analysis of the energy dispersions, we propose a scaling relation [Formula: see text] and [Formula: see text] for [Formula: see text] and z that only depends on the Hopf insulator Hamiltonian parameters p and q and the axis direction [Formula: see text]. An anisotropic quantum hyperscaling relation is also obtained.

Finite temperature effects in quantum systems with competing scalar orders.

The study of the competition or coexistence of different ground states in many-body systems is an exciting and actual topic of research, both experimentally and theoretically. Quantum fluctuations of a given phase can suppress or enhance another phase depending on the nature of the coupling between the order parameters, their dynamics and the dimensionality of the system. The zero temperature phase diagrams of systems with competing scalar order parameters with quartic and bilinear coupling terms have been previously studied for the cases of a zero temperature bicritical point and of coexisting orders. In this work, we apply the Matsubara summation technique from finite temperature quantum field theory to introduce the effects of thermal fluctuations on the effective potential of these systems. This is essential to make contact with experiments. We consider two and three-dimensional materials characterized by a Lorentz invariant quantum critical theory, i.e., with dynamic critical exponent z = 1, such that time and space scale in the same way. We obtain that in both cases, thermal fluctuations lead to weak first-order temperature phase transitions, at which coexisting phases arising from quantum corrections become unstable. We show that above this critical temperature (T c), the system presents scaling behavior consistent with that approaching a quantum critical point. Below the transition the specific heat has a thermally activated contribution with a gap related to the size of the domains of the ordered phases. We obtain that T c decreases as a function of the distance to the zero temperature classical bicritical point (ZTCBP) in the coexistence region, implying that in our approach, the system attains the highest T c above the fine tuned value of this ZTCBP.

Detection of genes providing salinity-tolerance in rice / Detecção de genes que conferem tolerância à salinidade em planta de arroz

The present study aimed to identify salinity-tolerant genes in three cultivars (BRS-7 Taim, BRS Querência and BRS Atalanta) of Oryza sativa L. ssp. indica S. Kato and in three cultivars (BRS Bojurú, IAS 12-9 Formosa and Goyakuman) of Oryza sativa L. ssp. japonica S. Kato. Ten days after emergence seedlings were transferred to a greenhouse and placed in a 15L vessel with half strength Hoagland nutrient solution, which was changed every four days, under controlled temperature and humidity. Plants were harvested 56 days after transfer. DNA extraction was carried out by CTAB method and salinity-tolerant genes SOS and CK1 were identified by in silico research. Amplification of gene sequence was performed with in silico primers. Bands were detected by agar gel electrophoresis and visualized under ultraviolet light after staining with ethidium bromide. Gene SOS1 fragments were present in all cultivars, except in BRS Atalanta, whereas CK1 gene was present in all evaluated cultivars. Results show that salinity-tolerant genes under analysis were identified in the two sub-species.

O estudo teve como objetivo identificar genes envolvidos na tolerância à salinidade em três cultivares (BRS-7 Taim, BRS Querência e BRS Atalanta) de Oryza sativa L. ssp. indica S. Kato e em três cultivares (BRS Bojurú, IAS 12-9 Formosa e Goyakuman) de Oryza sativa L. ssp. japonica S. Kato. As plântulas foram transferidas para casa de vegetação, sob temperatura e umidade relativa controladas, dez dias após a emergência e colocadas em bacia com capacidade para 15 litros, contendo solução nutritiva de Hoagland, meia força, a qual foi mudada em intervalos de quatro dias. A coleta foi aos 56 dias após a transferência. A extração de DNA foi realizada pelo método CTAB. Os genes SOS e CK1, envolvidos na tolerância à salinidade, foram identificados por meio de pesquisa in sílico . A amplificação das sequências do gene foi realizada utilizando-se primers também desenhados in sílico. As bandas foram detectadas por eletroforese em gel de agarose e visualizadas em luz ultravioleta após coloração com brometo de etídio. Fragmentos do gene SOS1 foram encontrados em todas as cultivares, exceto para BRS Atalanta. O gene CK1 esteve presente em todas as cultivares avaliadas. Os resultados mostram que os genes estudados estão presentes em ambas as subespécies.

Análise de crescimento de plantas de rabanete submetidas a doses de adubação nitrogenada / Growth analysis of radish plants subjected to doses of nitrogen

O experimento foi conduzido em casa de vegetação, na Universidade Federal de Pelotas, Campus Capão do Leão, RS, com o objetivo avaliar comparativamente o crescimento de plantas de rabanete Comprido de Ponta Branca submetido a diferentes doses de nitrogênio (0,15 e 30 kg ha-1 de N). As plantas foram coletadas a intervalos regulares de três dias a partir dos 13 dias após a semeadura até o final do ciclo da cultura. Determinaram-se a massa seca total, taxa de produção de matéria seca, taxa de crescimento relativo, taxa assimilatória líquida, índice de área foliar, taxa de crescimento relativo de área foliar, razões de área foliar e massa foliar e a área foliar específica. O tratamento de 15 kg ha-1 de N proporcionou melhores características de crescimento e maior acúmulo de matéria seca quando comparada aos demais tratamentos.

The experiment was conducted in a greenhouse at Universidade Federal de Pelotas, Campus Capão do Leão, RS. In order to evaluate comparatively the growth of radish plants Comprido de Ponta Branca under different nitrogen levels (0, 15 e 30 kg ha-1 de N). Plants were collected at regular intervals of three days, from 13 days after sowing until the end of the crop cycle. The total dry matter production, dry matter production rate, relative growth rate, net assimilation rate, leaf area index, relative growth rate of leaf area, leaf area ratio, leaf mass and specific leaf area were determined. The treatment of 15 kg ha-1 de N provided better growth characteristics and higher dry matter accumulation when compared to other treatments.

Análise comparativa de crescimento entre genótipos de pimenta cultivados em casa de vegetação / Comparative analysis of growth between genotypes of pepper grown in greenhouse

O presente trabalho objetivou avaliar comparativamente as características fisiológicas de crescimento entre duas cultivares de pimenta, em casa de vegetação. As plantas foram coletadas a partir do décimo quarto dias após o transplante (DAT), a intervalos regulares de quatorze dias após o transplante até final do ciclo de cultivo. Em cada coleta, as plantas foram separadas em órgãos (raiz, caule, folha e fruto). Foram determinadas a matéria seca total (Wt), as taxas de produção de matéria seca (Ct) e de crescimento relativo (Rw), taxa assimilatória líquida (Ea), índice de área foliar (L), taxa de crescimento relativo de área foliar (Ra), razão de área foliar (Fa), razão de massa foliar (Fw), área foliar específica (Sa) e o índice de colheita (Hi). A partir da análise conjunta e comparativa dos dados de crescimento das cultivares de pimenta estudadas, a cultivar Vulcão obteve maiores Ea , Fa e Ra . Entretanto, menores Wt , Ct e Hi em relação a cultivar Doce. Assim, a cultivar Doce foi superior à Vulcão no que tange aos atributos de crescimento estudados, em condições de casa de vegetação.

This study aimed to comparatively evaluate the physiological characteristics of growth between two cultivars of pepper in the greenhouse. Plants were collected from the fourteenth day after transplanting (DAT) at regular intervals of fourteen days after the transplant by the end of the crop cycle. At each sampling, plants were separated into organs (root, stem, leaf and fruit). We determined the total dry weight (Wt), rates of dry matter production (Ct) and relative growth (Rw), net assimilation rate (Ea), leaf area index (L), relative growth rate of leaf area (Ra), leaf area ratio (Fa), leaf weight ratio (Fw), specific leaf area (Sa) and harvest index (Hi). From the joint analysis and comparative data of growth of pepper cultivars, the cultivar had the highest Vulcão Ea , Fa and Ra . However, lower Wt , Ct and Hi in relation to cultivate Doce. Thus the cultivar was higher than the Doce Vulcão in respect to growth attributes studied in greenhouse conditions.

Enzyme expression in indica and japonica rice cultivars under saline stress - doi: 10.4025/actascibiolsci.v34i4.8535

The southern State of Rio Grande do Sul (RS) is the main rice producer in Brazil with a 60% participation of the national production and 86% participation of the region. Rice culture irrigation system is done by flooding, which leads to soil salinization, a major environmental constraint to production since it alters the plants metabolism exposed to this type of stress. The indica cultivar, widely used in RS, has a higher sensitivity to salinity when compared to that of the japonica cultivar in other physiological aspects. Current research analyzes enzymes expression involved in salt-subjected indica and japonica rice cultivars respiration. Oryza sativa L. spp. japonica S.Kato (BRS Bojuru, IAS 12-9 Formosa and Goyakuman) and Oryza sativa L. spp. indica S. Kato (BRS Taim-7, BRS Atalanta and BRS Querencia) were the cultivars employed. Seedlings were transferred to 15 L basins containing 50% Hoagland nutrient solution increased by 0, 25, 50, 75 and 100 mM NaCl, and collected at 14, 28 and 42 days after transfer (DAT). Plant tissues were macerated and placed in eppendorf tubes with Scandálios extractor solution. Electrophoresis was performed in 7% of the polyacrylamide gels in vertical vats. Bands were revealed for the following enzymes systems: esterase, alcohol dehydrogenase, phosphoglucoisomerase, malate dehydrogenase, malic enzyme and alpha amylase. The enzymes expression was

Enzyme expression in indica and japonica rice cultivars under saline stress / Expressão de enzimas em cultivares de arroz indica e japonica sob estresse salino

The southern State of Rio Grande do Sul (RS) is the main rice producer in Brazil with a 60% participation of the national production and 86% participation of the region. Rice culture irrigation system is done by flooding, which leads to soil salinization, a major environmental constraint to production since it alters the plants' metabolism exposed to this type of stress. The indica cultivar, widely used in RS, has a higher sensitivity to salinity when compared to that of the japonica cultivar in other physiological aspects. Current research analyzes enzymes expression involved in salt-subjected indica and japonica rice cultivars' respiration. Oryza sativa L. spp. japonica S.Kato (BRS Bojuru, IAS 12-9 Formosa and Goyakuman) and Oryza sativa L. spp. indica S. Kato (BRS Taim-7, BRS Atalanta and BRS Querencia) were the cultivars employed. Seedlings were transferred to 15 L basins containing 50% Hoagland nutrient solution increased by 0, 25, 50, 75 and 100 mM NaCl, and collected at 14, 28 and 42 days after transfer (DAT). Plant tissues were macerated and placed in eppendorf tubes with Scandálios extractor solution. Electrophoresis was performed in 7% of the polyacrylamide gels in vertical vats. Bands were revealed for the following enzymes systems: esterase, alcohol dehydrogenase, phosphoglucoisomerase, malate dehydrogenase, malic enzyme and alpha amylase. The enzymes expression was greater in subspecies japonica, with more intense bands in proportion to salinity increase. Results show that enzyme systems are involved in the salinity defense mechanisms in O. sativa spp. japonica cultivar.

O Estado do Rio Grande do Sul (RS) destaca-se como principal produtor de arroz, participando com 60% da produção nacional e 86% da regional. O sistema de irrigação da cultura é por inundação, que induz o solo à salinização, um dos maiores limitadores ambientais à produção, alterando o metabolismo da plantas expostas a este tipo de estresse. As cultivares indicas amplamente utilizadas no RS demonstram maior suscetibilidade à salinidade quando comparadas às japonicas em outros aspectos fisiológicos. O objetivo da pesquisa foi analisar a expressão de enzimas envolvidas na respiração de cultivares de arroz, indica e japonica, submetidas à salinidade. Foram utilizadas cultivares de Oryza sativa L. spp. japonica S. Kato (BRS Bojuru, IAS 12-9 Formosa e Goyakuman) e de Oryza sativa L. spp. indica S. Kato (BRS-7 Taim, BRS Querência e BRS Atalanta). As plântulas foram transferidas para bacias de 15 L, contendo solução nutritiva de Hoagland meia força acrescida de 0, 25, 50, 75 e 100 mM de NaCl. A coleta foi aos 14, 28 e 42 dias. Os tecidos vegetais foram macerados e colocados em tubos eppendorf com solução extratora de Scandálios. A eletroforese foi realizada em géis de poliacrilamida 7% em cubas eletroforéticas verticais. As bandas foram reveladas para os sistemas enzimáticos esterase, álcool desidrogenase, fosfoglico isomerase, malato desidrogenase, enzima málica e alfa amilase. A expressão das enzimas foi maior na subespécie japonica, com bandas mais intensas conforme o aumento da salinidade. Conclui-se que tais sistemas enzimáticos estejam envolvidos em mecanismos de tolerância ao estresse salino nas cultivares de O. sativa spp. japonica.

Inibidores de tirosino quinase na leucemia mieloide crônica / Tyrosine kinase inhibitors in chronic myeloid leukemia

A leucemia mieloide crônica (LMC) é uma neoplasia da medula óssea originada da translocação entre os cromossomos 9 e 22 t(9:22)(q34;11) e forma o gene híbrido BCR-ABL, que possui intensa atividade tirosino quinase, sendo responsável pela proliferação das células tumorais. Um grande avanço no tratamento da LMC foi conquistado com o surgimento dos inibidores da tirosino quinase, entre eles o imatinibe, que vem demonstrando ser efetivo na maior parte dos pacientes com LMC por apresentar respostas duradouras. Entretanto, há pacientes resistentes ou que desenvolvem resistência durante o tratamento com esta droga; sendo assim, inibidores de tirosino quinase de segunda geração, como o dasatinibe e o nilotinibe, foram desenvolvidos apresentando maior potência com a finalidade de diminuir a chance de desenvolvimento de resistência. O bosutinibe e o INNO-406 estão sendo estudados para atender pacientes resistentes às drogas anteriormente citadas e também com a finalidade de diminuir efeitos colaterais das mesmas; entretanto, eles ainda estão em fase clínica de estudo. Há ainda outras drogas inibidoras da tirosino quinase que estão em desenvolvimento na fase clínica ou pré-clínica. A partir do desenvolvimento destas novas drogas, múltiplas opções de tratamento para os pacientes com LMC poderão ser propostas, podendo, desta forma, individualizar o tratamento de acordo com o que cada paciente necessita. Este estudo visa descrever as drogas antineoplásicas que têm como mecanismo de ação a inibição da enzima tirosino quinase na LMC.

Chronic myeloid leukemia (CML) is a neoplastic transformation of the hematopoietic system resulting from a t(9;22)(q34;q11) translocation forming a BCR-ABL hybrid gene which has intense enzyme tyrosine kinase activity responsible for the proliferation of tumor cells. A dramatic positive response was achieved in CML patients with imatinib. This drug is effective in most patients because it presents long-lasting responses. However, some patients are resistant or develop resistance during treatment, particularly in the late-stage disease, thus second generation tyrosine kinase inhibitors such as dasatinib and nilotinib were developed to reduce the risk of developing resistance. Bosutinib and INNO-406 are being developed to treat resistant patients and also to reduce the side effects of the aforementioned drugs. Additionally, novel tyrosine kinase inhibitors are in clinical or preclinical development stages. In the future, multiple treatment options will be available for patients with CML, with the possibility to individualize the treatment according to the needs of each patient. In the current study we describe antineoplastic drugs that act as tyrosine kinase enzyme inhibitors in CML.