Thermal dependence of the zero-bias conductance through a nanostructure

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Usando um voltímetro para medir tempo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production of clavulanic acid and cephamycin C by Streptomyces clavuligerus under different fed-batch conditions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A degradação social do trabalho e da natureza no contexto da monocultura canavieira paulista

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A contradição entre universalidade da cultura humana e o esvaziamento das relações sociais: por uma educação que supere a falsa escolha entre etnocentrismo ou relativismo cultural

A tese do fim das metanarrativas defendida pelo pós-modernismo implica a negação da universalidade da cultura. Não se trata apenas do fato de que a cultura humana ainda não tenha alcançado um estágio de verdadeira universalidade nem mesmo se trata do fato de que a classe dominante tenha até hoje submetido a cultura humana a seus interesses particulares de classe e, para tanto, tenha sufocado e destruído muito da riqueza contida nas culturas locais. Para o pós-modernismo, o problema não reside na visão burguesa de cultura humana, mas sim na própria idéia de que possa haver uma cultura universal. Os pós-modernos afirmam que qualquer projeto educacional pautado na idéia da existência ou da possibilidade de uma cultura universal é um projeto conservador, autoritário e etnocêntrico. O texto defende a tese de que a concepção marxiana acerca do processo histórico de constituição da riqueza humana universal contém os elementos teóricos necessários para a superação da falsa opção, postulada pelas diversas correntes do pós-modernismo, entre o etnocentrismo e o relativismo cultural. em Marx, a universalização da cultura humana ocorre, na sociedade capitalista, por meio da universalização do valor de troca das mercadorias como mediação fundamental das relações sociais. Trata-se, portanto, de um processo dialético no qual ocorrem ao mesmo tempo a humanização e a alienação do gênero humano e dos indivíduos. O texto conclui com a apresentação dos desafios que, a partir dessa concepção marxiana sobre a riqueza universal, devem ser enfrentados no processo de construção de uma pedagogia marxista.

Ocorrência de Atelocynus microtis (Sclater, 1882) na Floresta Nacional do Jamari, estado de Rondônia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of cyproterone acetate on alpha1-adrenoceptor subtypes in rat vas deferens

Gonadal hormones regulate the expression of alpha1-adrenoceptor subtypes in several tissues. The present study was carried out to determine whether or not cyproterone acetate, an anti-androgenic agent, regulates the alpha1-adrenoceptor subtypes that mediate contractions of the rat vas deferens in response to noradrenaline. The actions of subtype selective alpha1-antagonists were investigated in vas deferens from control and cyproterone acetate-treated rats (10 mg/day, sc, for 7 days). Prazosin (pA2 ~9.5), phentolamine (pA2 ~8.3) and yohimbine (pA2 ~6.7) presented competitive antagonism consistent with activation of alpha1-adrenoceptors in vas deferens from both control and treated rats. The pA2 values estimated for WB 4101 (~9.5), benoxathian (~9.7), 5-methylurapidil (~8.5), indoramin (~8.7) and BMY 7378 (~6.8) indicate that alpha1A-adrenoceptors are involved in the contractions of the vas deferens from control and cyproterone acetate-treated rats. Treatment of the vas deferens from control rats with the alpha1B/alpha1D-adrenoceptor alkylating agent chloroethylclonidine had no effect on noradrenaline contractions, supporting the involvement of the alpha1A-subtype. However, this agent partially inhibited the contractions of vas deferens from cyproterone acetate-treated rats, suggesting involvement of multiple receptor subtypes. To further investigate this, the actions of WB 4101 and chloroethylclonidine were reevaluated in the vas deferens from rats treated with cyproterone acetate for 14 days. In these organs WB 4101 presented complex antagonism characterized by a Schild plot with a slope different from unity (0.65 ± 0.05). After treatment with chloroethylclonidine, the complex antagonism presented by WB 4101 was converted into classical competitive antagonism, consistent with participation of alpha1A-adrenoceptors as well as alpha1B-adrenoceptors. These results suggest that cyproterone acetate induces plasticity in the alpha1-adrenoceptor subtypes involved in the contractions of the vas deferens.

Simulação da dinâmica operacional de uma linha industrial de abate de suínos

Este trabalho teve como objetivo implementar um modelo computacional para simular a dinâmica operacional de uma linha industrial de abate de suínos. O sistema real modelado pertence à empresa Frigorífico Frimesa, sediada no município de Medianeira (PR). O modelo implementado é tipo dinâmico, discreto e estocástico. Este simula 34 operações unitárias e foi estruturado com o uso da linguagem de simulação EXTEND TM. Para validação do modelo foram coletados dados relativos a cinco dias de operação, em que foram abatidos 1.346, 1.630, 1.360, 1.585 e 1.550 suínos, respectivamente. Como parâmetros de comparação entre os dados obtidos a partir do sistema e gerados pelo modelo foram selecionadas as seguintes variáveis: (i) tempo de duração da operação; (ii) tempo de deslocamento da insensibilização até a depiladeira; (iii) tempo deslocamento da insensibilização até a câmara fria; (iv) número de carcaças re-inspecionadas; e (v) número final de carcaças. Na validação do modelo, foi constatado que, para a variável tempo de duração da operação por meio do teste Tukey a 1% de significância, não foram detectadas diferenças estatísticas entre os valores obtidos do sistema real e os gerados pelo modelo. Considerando-se esta e outras análises, foi concluído que o modelo aplica-se à finalidade para a qual foi implementado. Sendo assim, foram realizadas duas análises de sensibilidade. Na primeira, ao alterar o número de suínos a abater de 1 mil para 2 mil, foi determinado que os tempos de duração da operação variariam de 6,20 a 10,10 h, respectivamente. Para a segunda, ao abater 1.340 suínos e alterar a velocidade das nórias de 300 para 600 animais por hora, o tempo de duração da operação passou de 8,10 para 7,40 h, respectivamente.

Feuerbach e Stirner: algumas considerações sobre linguagem e política

Habitualmente não se presta atenção ao fato de que a Primeira Parte da Ideologia Alemã (Feuerbach) foi a última a ser redigida por Marx. O texto, tal como nos aparece hoje, encobre portanto a gênese da crítica ao Humanismo. Esta última, como este pequeno ensaio pretende indicar, só poderia brotar do contacto meticuloso com o texto do Único e sua Propriedade. Após a leitura de Stirner, Marx pôde se acreditar liberado deste último fantasma especulativo e ideológico: o Homem.

Estimation of outcrossing rate in a breeding population of Eucalyptus urophylla with dominant RAPD and AFLP markers

Eucalyptus breeding is typically conducted by selection in open-pollinated progenies. As mating is controlled only on the female side of the cross, knowledge of outcrossing versus selling rates is essential for maintaining adequate levels of genetic variability for continuous gains. Outcrossing rate in an open-pollinated breeding population of Eucalyptus urophylla was estimated by two PCR-based dominant marker technologies, RAPD and AFLP, using 11 open-pollinated progeny arrays of 24 individuals. Estimated outcrossing rates indicate predominant outcrossing and suggest maintenance of adequate genetic variability within families. The multilcous outcrossing rate (t(m)) estimated from RAPD markers (0.93 +/- 0.027), although in the same range, was higher (alpha > 0.01) than the estimate based on AFLP (0.89 +/- 0.033). Both estimates were of similar magnitude to those estimated for natural populations using isozymes. The estimated Wright's fixation index was lower than expected based on t, possibly resulting from selection against selfed seedlings when sampling plants for the study. An empirical analysis suggests that 18 is the minimum number of dominant marker loci necessary to achieve robust estimates of t,. This study demonstrates the usefulness of dominant markers, both RAPD and AFLP, for estimating the outcrossing rate in breeding and natural populations of forest trees. We anticipate an increasing use of such PCR-based technologies in mating-system studies, in view of their high throughput and universality of the reagents, particularly for species where isozyme systems have not yet been optimized.

Excitation spectrum for ultrafast photogeneration of charged solitons in polyacetylene

Ultrafast photoinduced absorption by infrared-active vibrational modes is used to detect charged solitons in oriented trans-polyacetylene. Soliton pairs are photogenerated within similar to250 fs with quantum efficiencies (phi(ch)) approaching unity. The excitation spectrum of phi(ch) shows an onset at similar to1.0 eV with a weak photon energy dependence up to 4.7 eV. The results are consistent with the ultrafast soliton formation predicted by Su and Schrieffer and with the Su-Scrieffer-Heeger threshold of 2E(g)/pi for soliton pair production. The recombination dynamics of charged solitons is very fast (initial decay<1 ps) with a modest dependence on the pump photon energy.

STUDY OF AMNONIFYING BACTERIA BEHAVIOR IN THE LAKES CARIOCA AND D-HELVECIO (RIO-DOCE-VALLEY-MG)

The study of the amnonifying bacteria behavior in the lakes Carioca and D. Helvecio, which belong to the natural lacustrine system of the Rio Doce Valley - Minas Gerais - Brazil, during the period from March to November, showed a similar seasonal variation in both lakes, with higher population density in March and November (raining period) and lower density in May, July and September (dry period). The vertical variation was also relatively similar for both lakes, were during the thermal stratification the distribution was regular along the water column, while during the period of thermal stratification the populational density was remarkably different at different depths. The characterized ammonifying types to the genera Acinetobacter, Moraxella and Proteus, which in culture reveal high amnonifying activity with values which have reached 30,8 mug/l of ammonia per population unity (105 bacteria/ml).

On designing linear tunable high-Q OTA-C filters with low sensitivity

This paper discusses a design approach for a high-Q low-sensitivity OTA-C biquad bandpass section. An optimal relationship is established between transconductances defining the differencebeta - gamma in the Q-factor denominator, setting the Q-sensitivity to tuning voltages around unity. A 30-MHz filter was designed based on a 0.35 mum CMOS process and V-DD=3.3 V. A range of circuit simulation supports the theoretical analysis. Q-factor spans from 20.5 to 60, while ensuring filter stability along the tuning range. Although a triode-operating OTA is used, the procedure can be extended to other types of transconductor.

Atypical beta-adrenoceptor subtypes mediate relaxations of rabbit corpus cavernosum

This study was performed to characterize the beta-adrenoceptor population in rabbit isolated corpus cavernosum (RbCC) by using nonselective and selective beta-adrenoceptor agonists and antagonists in functional assays. Metaproterenol, ritodrine, fenoterol, and 8-hydroxy-5-[(1R)-1-hydroxy-2-[N-[(1R)-2-(rho-methoxy-phenyl)1-methylethyl] amino] ethyl] carbostyril (TA 2005) (3-100 nmol each) dose dependently relaxed the RbCC preparations. These relaxations were markedly reduced by N-omega-nitro-L-arginine methyl ester (L-NAME; 10 muM) and 1H-[1,2,4]-oxadiazolo-[4,3,-a]quinoxalin-1-one (ODQ) (10 muM), whereas the adenylyl cyclase inhibitor SQ 22,536 [9-(2-tetrahydrofuryl)adenine] (10 muM) had no effect. In contrast, neither L-NAME nor ODQ affected the isoproterenol-induced RbCC relaxations, but SQ 22,536 abolished this response. Sildenafil (1 muM) significantly potentiated the relaxations induced by beta(2)-agonists without affecting the isoproterenol-evoked relaxations. Rolipram (10 muM) enhanced the relaxations elicited by isoproterenol but had no effect on those induced by the selective beta(2) agonists. Propranolol and (+/-)-1-[2,3-(dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methylethyl)amino]-2-butanolhydrochloride (ICI 118,551) determined a rightward shift in the concentration-response curves to isoproterenol in a noncompetitive manner with a reduction of maximum response at the highest antagonist concentration, with the slope values significantly different from unity. Propranolol and ICI 118,551 had no effect on the relaxations elicited by fenoterol, TA 2005, metaproterenol, and ritodrine. Atenolol and 1-[2-((3-carbamoyl-4-hydroxy)phenoxy) ethylamino]-3-[4-(1-methyl-4-trifluoromethyl-2-imidazolyl)-phenoxy]2-propanol methanesulfonate (CGP 20712A) (0.1-10 muM) failed to affect the relaxations induced by all tested beta-adrenoceptor agonists. Our study revealed the existence of two atypical beta-adrenoceptors in the rabbit erectile tissue. Isoproterenol relaxes the rabbit cavernosal tissue by activating atypical beta-adrenoceptors coupled to adenylyl cyclase pathway, whereas the selective beta2-adrenoceptor agonists relax the RbCC tissue through another atypical beta-adrenoceptor subtype coupled to nitric oxide release from the sinusoidal endothelium.

Symbolic power, robotting, and surveilling

Symbolic power is discussed with reference to mathematics and formal languages. Two distinctions are crucial for establishing mechanical and formal perspectives: one between appearance and reality, and one between sense and reference. These distinctions include a nomination of what to consider primary and secondary. They establish the grammatical format of a mechanical and a formal world view. Such views become imposed on the domains addressed by means of mathematics and formal languages. Through such impositions symbolic power of mathematics becomes exercised. The idea that mathematics describes as it prioritises is discussed with reference to robotting and surveillance. In general, the symbolic power of mathematics and formal languages is summarised through the observations: that mathematics treats parts and properties as autonomous, that it dismembers what it addresses and destroys the organic unity around things, and that it simplifies things and reduces them to a single feature. But, whatever forms the symbolic power may take, it cannot be evaluated along a single good-bad axis.