Critical temperature of a fully anisotropic three-dimensional Ising model

The critical temperature of a three-dimensional Ising model on a simple cubic lattice with different coupling strengths along all three spatial directions is calculated via the transfer matrix method and a finite size scaling for L x L oo clusters (L=2 and 3). The results obtained are compared with available calculations. An exact analytical solution is found for the 2 x 2 oo Ising chain with fully anisotropic interactions (arbitrary J_x, J_y and J_z).Comment: 17 pages in tex using preprint.sty for IOP journals, no figure

Date palm-A gift for health and nutrition: national and international scenario

Date palm (Phoenix dactylifera L.), family Arecaceae or Palmae, is cultivated mostly in the arid regions of the world. The crop has played a significant role in the economy of these countries, provides nutritional security, besides helping to mitigate the adverse effects of desertification and climate change over centuries. Date palm personifies human civilization in the arid countries. It is estimated that there are 150 million date palms worldwide, and 75% of these in the Near East and North Africa region. According to the Food and Agriculture Organization (FAO) of the United Nations, the global production of dates has increased from just 1.8 million tons in 1962 to nearly 9.75 million tons in 2022. In India, commercial dates are cultivated mainly in the states of Gujarat and Rajasthan which are emerging as major producers of fresh dates. Besides, local and wild dates are abound across the country. Dates are consumed fresh or in dry form and considered a complete food, providing food and nutrition security through a wide range of essential nutrients that have beneficial effects on human health. This article presents an overview of dates on nutrition and human health besides giving an insight on propagation, production, protection, processing, marketing, and associated challenges plaguing the sector

Theoretical derivation of 1/f noise in quantum chaos

It was recently conjectured that 1/f noise is a fundamental characteristic of spectral fluctuations in chaotic quantum systems. This conjecture is based on the behavior of the power spectrum of the excitation energy fluctuations, which is different for chaotic and integrable systems. Using random matrix theory we derive theoretical expressions that explain the power spectrum behavior at all frequencies. These expressions reproduce to a good approximation the power laws of type 1/f (1/f^2) characteristics of chaotic (integrable) systems, observed in almost the whole frequency domain. Although we use random matrix theory to derive these results, they are also valid for semiclassical systems.Comment: 5 pages (Latex), 3 figure

Screening para resistência de 22 progênies de maracujazeiro-azedo ao vírus do endurecimento o fruto (CABMV).

Neste trabalho, objetivou-se avaliar e selecionar genótipos à severidade do vírus do endurecimento dos frutos em condições de casa-de-vegetação

Seleção de progênies de maracujazeiro-azedo para resistência à bacteriose (Xanthomonas axonopodis pv. passiflorae).

O presente trabalho teve como objetivo avaliar e selecionar genótipos de maracujazeiro azedo resistentes a mancha oleosa causada por Xanthomonas axonopodis pv. passiflorae, na fase de mudas, sob casa de vegetação

Contrastant banana accessions for resistance to the burrowing nematode, based on molecular markers RAPD.

This work aimed to proceed molecular characterization of seven banana accessions (Borneo, Grand Naine, 1304-06, 4249-05, 0337-02, 0323-03 and 4279-06) resistance to the nematode Radopholus similis. These accessions were selected taking in account the reproduction factor (RF) among 26 banana genotypes from a working collection belonging to Embrapa Mandioca e Fruticultura Tropical. The genomic DNA of the seven accessions was extracted, and 36 decamere primers had been used to obtain RAPD markers. The resulting markers were converted into a matrix of binary data. From that matrix the genetic distance between the accessions were estimated, for further clustering and graphic dispersion analyses. From a total of 521 RAPD markers generated, 420 (81%) were polymorphic, including 140 (27%) potentially promising for application on works related to genetic mapping of the resistance to R. similis. OPE-15, OPH-17, and OPG-09 were the primers that contributed to the highest number of bands promising for genetic mapping of resistance (12, 8, and 8, respectively). The genetic distances between accessions ranged from 0.106 to 0.455, with the longest one observed between cv. Borneo and the genotype 4279-06, considered as highly susceptible and resistant, respectively, to the nematode according to the RF. The graphic dispersion distinguished three groups of accessions, and most of resistant genotypes clustered together in the same group. The most contrastant genotypes for resistance (Borneo and 4249-05) were separated by a genetic distance of 0.374, and possessed a total of 114 polymorphic bands promising for genetic mapping of resistance. In addition, the results of pathogenicity tests were congruent with those obtained by RAPD analyses

Caracterização molecular, morfoagronômica e de qualidade de grãos de genótipos elite de cevada irrigada no Cerrado.

O objetivo deste trabalho foi gerar informações moleculares, morfoagronômicas e de qualidade de grãos, por meio da caracterização de genótipos elite de cevada irrigada e de estimativas de parâmetros genéticos, visando explorar a variabilidade genética existente e permitir a seleção de genitores e o desenvolvimento de variedades mais produtivas, com maior qualidade malteira e adaptadas a diferentes condições edafoclimáticas sob irrigação no Cerrado. Foram avaliados 30 genótipos elite de cevada, hexástica e dística, provenientes da Coleção de Trabalho da Embrapa Cerrados (Planaltina-DF), de origens diversas, adotando-se o delineamento experimental de blocos ao acaso, com quatro repetições, sob sistema de irrigação convencional. A variabilidade genética foi estimada utilizando 12 caracteres morfoagronômicos quantitativos, 10 caracteres de qualidade malteira e com base em 160 marcadores moleculares RAPD. Foram obtidos 160 marcadores RAPD, dos quais 141 (88,12%) foram polimórficos revelando a existência de elevada variabilidade genética, passível de ser utilizada no melhoramento genético. A análise de agrupamento mostrou uma tendência de agrupamento entre os genótipos mexicanos e estadunidenses, bem como de genótipos hexásticos. Observou-se a existência de variabilidade genética para caracteres qualitativos malteiros, sendo que os caracteres qualitativos que mais contribuíram foram o nitrogênio solúvel e ?-glucanas. Em relação às características morfoagronômicas, as que mais contribuíram para a variabilidade foram a área foliar da folha bandeira e o espigamento, enquanto o teor de proteína e o acamamento foram as que menos contribuíram. Foi verificada uma tendência de agrupamento dos materiais dísticos e hexásticos. As distâncias estimadas, por meio de marcadores moleculares e caracteres qualitativos e quantitativos, foram fracamente correlacionados. Os índices de seleção, baseado no ideótipo e de Elston, e a análise de agrupamento oportunizaram a seleção de genótipos promissores e indicação de cruzamentos para maximizar efeitos heteróticos e complementaridade gênica no programa de melhoramento genético da cevada irrigada no Cerrado. Como resultado finalístico desse trabalho, foi selecionada a BRS Savanna, para o cultivo em Goiás, Minas Gerais e no Distrito Federal