Slowly synchronizing automata and digraphs

We present several infinite series of synchronizing automata for which the minimum length of reset words is close to the square of the number of states. These automata are closely related to primitive digraphs with large exponent.Comment: 13 pages, 5 figure

Modelling of photonic wire Bragg Gratings

Some important properties of photonic wire Bragg grating structures have been investigate. The design, obtained as a generalisation of the full-width gap grating, has been modelled using 3D finite-difference time-domain simulations. Different types of stop-band have been observed. The impact of the grating geometry on the lowest order (longest wavelength) stop-band has been investigated - and has identified deeply indented configurations where reduction of the stop-bandwidth and of the reflectivity occurred. Our computational results have been substantially validated by an experimental demonstration of the fundamental stop-band of photonic wire Bragg gratings fabricated on silicon-on-insulator material. The accuracy of two distinct 2D computational models based on the effective index method has also been studied - because of their inherently much greater rapidity and consequent utility for approximate initial designs. A 2D plan-view model has been found to reproduce a large part of the essential features of the spectral response of full 3D models

Photon-Photon and Pomeron-Pomeron Processes in Peripheral Heavy Ion Collisions

We estimate the cross sections for the production of resonances, pion pairs and a central cluster of hadrons in peripheral heavy-ion collisions through two-photon and double-pomeron exchange, at energies that will be available at RHIC and LHC. The effect of the impact parameter in the diffractive reactions is introduced, and imposing the condition for realistic peripheral collisions we verify that in the case of very heavy ions the pomeron-pomeron contribution is indeed smaller than the electromagnetic one. However, they give a non-negligible background in the collision of light ions. This diffractive background will be more important at RHIC than at LHC.Comment: 22 pages, 1 Postscript figures, 4 tables, to appear in Phys. Rev.

Increased BDNF levels and NTRK2 gene association suggest a disruption of BDNF/TrkB signaling in autism

The brain-derived neurotrophic factor (BDNF), a neurotrophin fundamental for brain development and function, has previously been implicated in autism. In this study, the levels of BDNF in platelet-rich plasma were compared between autistic and control children, and the role of two genetic factors that might regulate this neurotrophin and contribute to autism etiology, BDNF and NTRK2, was examined. We found that BDNF levels in autistic children (n = 146) were significantly higher (t = 6.82; P < 0.0001) than in control children (n = 50) and were positively correlated with platelet serotonin distribution (r = 0.22; P = 0.004). Heritability of BDNF was estimated at 30% and therefore candidate genes BDNF and NTRK2 were tested for association with BDNF level distribution in this sample, and with autism in 469 trio families. Genetic association analysis provided no evidence for BDNF or NTRK2 as major determinants of the abnormally increased BDNF levels in autistic children. A significant association with autism was uncovered for six single nucleotide polymorphisms (SNPs) [0.004 (Z((1df)) = 2.85) < P < 0.039 (Z((1df)) = 2.06)] and multiple haplotypes [5 × 10(-4) (χ((3df)) = 17.77) < P < 0.042 (χ((9df)) = 17.450)] in the NTRK2 gene. These results do not withstand correction for multiple comparisons, however, reflect a trend toward association that supports a role of NTRK2 as a susceptibility factor for the disorder. Genetic variation in the BDNF gene had no impact on autism risk. By substantiating the previously observed increase in BDNF levels in autistic children in a larger patient set, and suggesting a genetic association between NTRK2 and autism, this study integrates evidence from multiple levels supporting the hypothesis that alterations in BDNF/tyrosine kinase B (TrkB) signaling contribute to an increased vulnerability to autism

Long-lived oscillons from asymmetric bubbles

The possibility that extremely long-lived, time-dependent, and localized field configurations (``oscillons'') arise during the collapse of asymmetrical bubbles in 2+1 dimensional phi^4 models is investigated. It is found that oscillons can develop from a large spectrum of elliptically deformed bubbles. Moreover, we provide numerical evidence that such oscillons are: a) circularly symmetric; and b) linearly stable against small arbitrary radial and angular perturbations. The latter is based on a dynamical approach designed to investigate the stability of nonintegrable time-dependent configurations that is capable of probing slowly-growing instabilities not seen through the usual ``spectral'' method.Comment: RevTeX 4, 9 pages, 11 figures. Revised version with a new approach to stability. Accepted to Phys. Rev.

Avaliação da incidência de antracnose, do desempenho e estado nutricional de variedades de mangueira, para cultivo orgânico, na região centro-norte do Estado de São Paulo.

A mudança do perfil do consumidor, aliada aos riscos da contaminação por agrotóxicos, tem levado à busca de alternativas ecologicamente apropriadas para produção de frutas. Os objetivos deste trabalho foram avaliar a incidência de antracnose, o desempenho e estado nutricional de variedades de mangueira conduzidas organicamente na região de Pindorama-SP. Foram utilizadas 17 variedades de mangueira. O experimento foi instalado em delineamento experimental em blocos completos ao acaso, com 17 tratamentos (variedades) e seis repetições. Foi avaliada a severidade de antracnose nas folhas, através de uma escala diagramática, atribuindo-se notas aos sintomas. Foram avaliados o crescimento e o desenvolvimento (altura da planta, perímetro do tronco e da copa) e o estado nutricional, mediante análise foliar, das diferentes variedades utilizadas. Através dos resultados obtidos, podem-se considerar como muito suscetíveis à antracnose as variedades Bourbon, Rocha e Rosa; e resistentes, as variedades IAC 111, Alfa, Beta e Parvin; as variedades de manga apresentaram o mesmo padrão de crescimento; as maiores alturas da planta corresponderam aos maiores diâmetros do tronco e da copa; a variedade Parvin apresentou o melhor desempenho dentre as variedades estudadas, com relação à resistência à antracnose, altura e diâmetro do caule e da copa, podendo ser recomendada ao cultivo orgânico. As variedades Omega e Alfa também apresentaram bom crescimento, podendo ser indicadas para esse cultivo, pelo menos nessa fase inicial; as variedades Surpresa e Rosa não apresentaram bom desempenho, no campo, em relação às demais, não devendo ser recomendadas para o cultivo orgânico, principalmente a variedade Rosa, bastante suscetível à antracnose. As concentrações de N, P e K foram elevadas na fase vegetativa das plantas, comparadas à baixa concentração de Ca; houve carência de Boro em todas as variedades estudadas. A manga Rosa, provavelmente, sofreu toxicidade ao excesso de manganês, ocasionando diminuição em seu desenvolvimento

TRIZ: creativity as exact science?

TRIZ is the acronym for the Russian phrase Theory of Inventive Problem Solving. Over two million patents have been examined, classified by level of inventiveness, and analyzed to look for principles of innovation. If these principles could be identified and codified, they could be taught to people to make the process of invention more predictable. In this paper we discuss some ideas to use this method in the preparation of Physics students.TRIZ é a sigla para as palavras russas que, em português, significam Teoria para a Resolução de Problemas Criativos. O estudo de mais de dois milhões de patentes no mundo tem permitido identificar princípios universais de invenção. Ensinando estes princípios e com a ajuda de técnicas psicológicas de geração de idéias, a metodologia TRIZ pretende aprofundar e dinamizar o processo criativo. Neste artigo apresentamos algumas sugestões de como utilizar o método TRIZ na formação de estudantes de Física.205209Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Nutritional characteristics of meat from lambs fed diets containing mulberry hay

The objective of this study was to evaluate the nutritional characteristics of meat from lambs fed diets containing 0%, 12.5% and 25.0% (dry matter (DM)) mulberry hay as a substitute for the concentrate. Twenty-four feedlot Île-de-France lambs with an average age of 60 days and bodyweight (BW) of 15 kg were fed in individual stalls and slaughtered at 32 kg BW, at approximately 130 days old. The chemical composition of the experimental diets contained, respectively, 584.4, 569.4 and 571.8 g DM/kg; 188.8, 185.1 and 184 g crude protein (CP)/kg and 29.9, 29.5 and 25.5 Mcal/kg DM for the mulberry hay inclusion levels of 0%, 12.5% and 25.0%, with a dietary forage to concentrate ratio of 50 : 50. The chemical composition of the meat was 757.9 g moisture/kg DM, 208.6 g CP/kg DM, 22.9 g crude fat/kg DM and 10.5 g ash/kg DM. Cholesterol concentration (36.07 mg/100 g) in the meat was not influenced by mulberry hay inclusion of the diet. An increase was observed in the concentrations of saturated pentadecanoic, heptadecanoic and arachidic acids; monounaturated heptadecenoic acid; and polyunsaturated α-linolenic, ɣ-linolenic and eicosapentaenoic acids. Nervonic and conjugated linoleic acid (CLA) concentrations responded quadratically, representing 3.7 g/kg and 5.9 g/kg of the meat when mulberry hay was included at 16.98% and 12.56%. Omega-3 acid concentrations increased, while the omega-3 : omega-6 ratio decreased in the meat of mulberry hay-fed animals. Inclusion of mulberry hay in lamb diets increases the amount of desirable fatty acids in their meat, whose nutritional characteristics are improved.Keywords: Chemical composition, fatty acids, feedlot, sheep mea

Magnetic And Superconducting Properties Of Ru Sr2 Gd1.5 Ce0.5 Cu2 O10-δ Samples: Dependence On The Oxygen Content And Aging Effects

The magnetic and superconducting properties of Ru Sr2 Gd1.5 Ce0.5 Cu2 O10-δ polycrystalline samples with different oxygen-doping levels are presented. A strong suppression of the superconducting temperature (Tc), as well as a reduction in the superconducting fraction, occurs as the oxygen content is reduced by annealing the samples in oxygen-deprived atmospheres. Drastic changes in the electrical resistivity are observed above Tc, possibly associated with oxygen removal, mainly from grain boundaries. However, the magnetic ordering is relatively less affected by the changes in oxygen content of the samples. The spin-glass transition is enhanced and shifted to higher temperatures with the reduction in oxygen content. This could be correlated with an increase in the spin disorder and frustration for the oxygen-depleted samples. Also, the same oxygen-vacancy-induced disorder could explain the reduction in the fraction of the sample showing antiferromagnetic order. We also report significant changes in the measured properties of the samples as a function of time. © 2005 The American Physical Society.7113Felner, I., Asaf, U., Levi, Y., Millo, O., (1997) Phys. Rev. B, 55, p. 3374. , PRBMDO 0163-1829 10.1103/PhysRevB.55.R3374Bernhard, C., Tallon, J.L., Niedermayer, Ch., Blasius, Th., Golnik, A., Brücher, E., Kremer, R.K., Ansaldo, E.J., (1999) Phys. Rev. B, 59, p. 14099. , PRBMDO. 0163-1829. 10.1103/PhysRevB.59.14099Awana, V.P.S., Karppinen, M., Yamauchi, H., (2003) Studies of High Tc Superconductors, 46, p. 77. , edited by A. V. Narlikar (Nova Science Publishers, New YorkMatvejeff, M., Awana, V.P.S., Jang, L.-Y., Liu, R.S., Yamauchi, H., Karppinen, M., (2003) Physica C, 392-396, p. 87. , PHYCE6 0921-4534Cardoso, C.A., Araujo-Moreira, F.M., Awana, V.P.S., Kishan, H., Takayama-Muromachi, E., De Lima, O.F., (2004) Physica C, 405, p. 212. , PHYCE6 0921-4534Cardoso, C.A., Araujo-Moreira, F.M., Awana, V.P.S., Takayama-Muromachi, E., De Lima, O.F., Yamauchi, H., Karppinen, M., (2003) Phys. Rev. B, 67, p. 020407. , PRBMDO 0163-1829 10.1103/PhysRevB.67.020407Shi, L., Li, G., Fan, X.J., Feng, S.J., Li, X.-G., (2003) Physica C, 399, p. 69. , PHYCE6 0921-4534Felner, I., Asaf, U., Ritter, F., Klamut, P.W., Dabrowski, B., (2001) Physica C, 364-365, p. 368. , PHYCE6 0921-4534Felner, I., Asaf, U., Galstyan, E., (2002) Phys. Rev. B, 66, p. 024503. , PRBMDO 0163-1829 10.1103/PhysRevB.66.024503Felner, I., Asaf, U., Levi, Y., Millo, O., (2000) Physica C, 334, p. 141. , PHYCE6 0921-4534 10.1016/S0921-4534(00)00250-1Awana, V.P.S., Ansari, M.A., Gupta, A., Saxena, R.B., Kishan, H., Buddhikot, D., Malik, S.K., (2004) Phys. Rev. B, 70, p. 104520. , PRBMDO 0163-1829 10.1103/PhysRevB.70.104520Yoshizawa, H., Mitsuda, S., Aruga, H., Ito, A., (1987) Phys. Rev. Lett., 59, p. 2364. , PRLTAO 0031-9007 10.1103/PhysRevLett.59.2364Binder, K., Young, A.P., (1986) Rev. Mod. Phys., 58, p. 801. , RMPHAT 0034-6861 10.1103/RevModPhys.58.801Mydosh, J.A., (1993) Spin Glasses An Experimental Introduction, , Taylor & Francis, LondonFelner, I., Galstyan, E., Herber, R.H., Nowik, I., (2004) Phys. Rev. B, 70, p. 094504. , PRBMDO 0163-1829 10.1103/PhysRevB.70.094504Shengelaya, A., Khasanov, R., Eschenko, D.G., Felner, I., Asaf, U., Savić, I.M., Keller, H., Müller, K.A., (2004) Phys. Rev. B, 69, p. 024517. , PRBMDO. 0163-1829. 10.1103/PhysRevB.69.024517Xue, Y.Y., Cao, D.H., Lorenz, B., Chu, C.W., (2002) Phys. Rev. B, 65, p. 020511. , PRBMDO 0163-1829 10.1103/PhysRevB.65.02051

Effect of feed deprivation during the post hatch holding birth time on the performance of broiler chicks from breeders of different age

The present research work hás been carried out in order to evaluate on the post born period of broilers from different broiler breeders age, the effect of feed deprivation between hatching and housing, on feed intake, weight gain, feed conversion and viability up to 42 days old, and weight lost. A total of 480 male chicks were distributed in a randomized factorial design of 3 X 3, with two broiler breeders age (30 and 60 weeks) and three feed deprivation times (0, 24, 48 h post hatching). The broiler breeder age did not affect the chicks lost of weight between hatching and housing, but the feed deprivation time affect this parameter. Chicks from 60-week-old broiler breeders showed greater feed intake 72 hours post hatching. Feed intake and weight gains were influenced by the breeder age 0f 7 and 21 days old, the chick from older breeder siplaying greater feed intake and weight gain. However, at 42 days of age, even if the birds had been subjected to periods of post hatching fasting, they did not display differences on their performance. Chicks from 30-week-old broiler breeders displayed a better feed conversion.Este estudo foi conduzido para avaliar o efeito do jejum entre o nascimento e o alojamento sobre o consumo de ração, ganho de peso, conversão alimentar e viabilidade criatória até 42 dias de idade; perda de peso e consumo de ração no período que suceder ao nascimento, em frangos de corte provenientes de matrizes de diferentes idades. Foram utilizados 480 pintainhos de corte, machos, em um delineamento inteiramente casualizado, em esquema fatorial 2 x 3 com os fatores idades de matriz (30 e 60 semanas) e períodos de jejum (0, 24 e 48 horas pós-eclosão). A idade da matriz não influenciou a perda de peso dos pintainhos entre o nascimento e o alojamento, variável esta afetada apenas pelo período de jejum a qual as aves foram submetidas. Pintainhos oriundos de matizes de 60 semanas de idade consumiram maior quantidade de ração nas 72 horas pós-eclosão. A idade da matriz influenciou também o consumo de ração e o ganho de peso aos 7 e 21dias de idade, sendo que pintainhos oriundos de matrizes mais velhas tiveram maior consumo e ganho de peso. No entanto, aos 42 dias, mesmo que as aves tenham sido submetidas a períodos de jejum pós-natal, não houve diferença no desempenho. Pintainhos oriundos de matrizes de 30 semanas tiveram melhor conversão alimentar nesta idade.