A estratégia de vendas, marketing e serviços (front office activities) de produtos de alta tecnologia na era do conhecimento

Trata das mudanças que já começaram a ocorrer no contexto empresarial e que regerão a nova economia do século xxi. Enfoca as novas exigência dos clientes, que se tornarão cada vez mais sofisticados e demandarão transformações nas atividades de front office. As empresas vencedoras estarão alicerçadas em três pilares principais: relacionamento de aprendizado com os clientes, liderança que promova a adaptação e recursos humanos autogerenciados.

Activation of bovine oocytes by strontium combined or not with an electric pulse

O objetivo deste trabalho foi avaliar as taxas de ativação e de clivagem de oócitos bovinos tratados com estrôncio (10mm de SrCl2), após maturação in vitro por 27-28 horas. No experimento 1, os tratamentos foram: S4 - ativação pelo estrôncio por 4 horas; S12 - ativação pelo estrôncio por 12 horas; S30 - ativação pelo estrôncio por 30 horas; e P - ativação por pulso elétrico (3 pulsos de 1,0kv/cm). No experimento 2 os tratamentos foram: PS4 - ativação combinada pelo pulso elétrico e pelo estrôncio por 4 horas; S4P - ativação pelo estrôncio por 4 horas e pelo pulso elétrico; e PS30 - ativação pelo pulso elétrico e pelo estrôncio por 30 horas. No experimento 1, todos os tratamentos apresentaram taxas similares de ativação (83-90%; P>0,05). Para clivagem, P foi melhor (53%; P<0,05) do que todos os tratamentos com estrôncio (6 a 28%). No experimento 2, o tratamento S4P apresentou melhor taxa de ativação (88%; P<0,05) do que PS4 e PS30 (60 e 68%, respectivamente). Para clivagem, observou-se o mesmo padrão, S4P (65%; P<0,05) e PS4 e PS30 (37% e 44%, respectivamente). Conclui-se que o estrôncio é capaz de ativar oócitos bovinos e sua combinação com pulso elétrico não melhora a ativação. Este é o primeiro relato demonstrando que o estrôncio ativa oócitos bovinos.

Perfil imuno-histoquímico do infiltrado inflamatório no front de invasão em carcicomas epidermóides de língua e lábio inferior

The progression of the oral squamous cells carcinomas (OSCCs) seems to suffer influence from related factors to the host, as local and systemic immunologic response, which are essential to the antineoplasic defenses. The purpose of this study was evaluate the local immunity in 30 tongue and 20 lower lip SCC by immunohistochemistry method, utilizing antibodies anti-CD3, CD4, -CD8, -CD25 e -ζ(zeta), which immunoexpressions were compared considering the anatomical localization, the intensity of the inflammatory infiltrate into the front of invasion and metastases. The CD4/CD8+ ratio was calculated for each case and associate with the mentioned variable, being the intensity of the inflammatory infiltrated also compared with the anatomical localization and metastase and for this the cases had been grouped in two categories: (n = 10) absent/scarce inflammatory infiltrate; and (n = 40) moderate/intense infiltrate. Fisher´s exact test was performed (α= 0.05) and it was not observed any significant correlation between these groups with anatomical sites and metastases. With regard to the immunoexpression, the CD3+, CD4+, CD8+ and CD25+ cells count was higher in the lower lip SCCs while the anti-ζimmunomarcation was more evident in the non metastatic cases. Through the statistical analyses, it was verified that the CD3 exhibited positive-significant correlation with the inflammatory infiltrate (p = 0.023). Furthermore, antibodies against CD8 and CD25 cells were also significantly correlated with the inflammatory infiltrate (p = 0.002 and 0.030, respectively) and with the anatomical site (p = 0.004 and p = 0.004) mainly in the lower lip SCCs. CD4/CD8 ratio did not show significant association with metastase nor with anatomical localization. We conclude that the inflammatory infiltrated of the Bryne s (1998) system did not constitute an indicator of aggressiveness in the tongue and lower lip SCCs analyzed and that clinical behavior of the SCCs studied was related in part to the immunohistochemical profile of infiltrated the inflammatory present in tumoral invasion front

The effect of acoustic mode on time-resolved temperature measurements in a Rijke-tube pulse combustor

Radial profiles are reported of average and rms temperature in a propane flame for the first, second, and third acoustic modes at four different axial positions above the burner in a Rijke-tube combustor. Selected plots of the power spectral density (PSD) of temperature fluctuations are also reported. These radial profiles are then compared to similar ones made in the same flame, but in the absence of the acoustic field. Visual observations and photographs of the flame showed a remarkable change in flame height and structure with the onset of acoustic oscillations. This reduction in flame length, caused by the enhanced mixing due to the acoustic velocity fluctuations, gave rise to higher and lower average and rms temperatures near or well above the burner, respectively. In general, the PSD plots had a broad frequency content. The general trend was a decrease in magnitude with an increase in frequency. All cases presented broad-band peaks at around 5 Hz related to the flame flickering phenomenon. Preferred frequencies were observed in the oscillating PSD plots related to the fundamental frequency as well as subharmonics in the tube. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Comparative degradation of ZnO- and SnO(2)-based polycrystalline non-ohmic devices by current pulse stress

The degradation behaviour of SnO(2)-based varistors (SCNCr) due to current pulses (8/20 mu s) is reported here for the first time in comparison with the ZnO-based commercial varistors (ZnO). Puncturing and/or cracking failures were observed in ZnO-based varistors possessing inferior thermo-mechanical properties in comparison with that found in a SCNCr system free of failures. Both systems presented electric degradation related to the increase in the leakage current and decrease in the electric breakdown field, non-linear coefficient and average value of the potential barrier height. However, it was found that a more severe degradation occurred in the ZnO-based varistors concerning their non-ohmic behaviour, while in the SCNCr system, a strong non-ohmic behaviour remained after the degradation. These results indicate that the degradation in the metal oxide varistors is controlled by a defect diffusion process whose rate depends on the mobility, the concentration of meta-stable defects and the amount of electrically active interfaces. The improved behaviour of the SCNCr system is then inferred to be associated with the higher amount of electrically active interfaces (85%) and to a higher energy necessary to activate the diffusion of the specific defects.

Generalization of the Y-differential autotransformer for 12- and 18-pulse converters

This work proposes a methodology to generalize the Y-connections for 12- and 18-pulse autotransformers. A single mathematical expression, obtained through simple trigonometric operations, represents all the connections. The proposed methodology allows choosing any ratio between the input and the output voltages. The converters can operate either as step-up or as step-down voltage. To simplify the design of the windings, graphics are generated to calculate the turn-ratio and the polarity of each secondary winding, with respect to the primary winding. A design example, followed by digital simulations, illustrates the presented steps. Experimental results of two prototypes (12 and 18 pulses) are presented. The results also show that high power factor is an inherent characteristic of multi-pulse converters, without any active or passive power factor pre-regulators needs. (c) 2005 Elsevier B.V. All rights reserved.

Cortactin is associated with perineural invasion in the deep invasive front area of laryngeal carcinomas

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

Differential pulse voltammetric determination of nitrite with gold ultramicroelectrode

The application of disk shaped gold ultramicroelectrode for nitrite determination with and without addition of supporting electrolyte was studied using the differential pulse voltammetric method. The well-defined peak for nitrite oxidation near 0.8V (vs. Ag/AgCl reference electrode) was used to obtain analytical plots in the concentration range from 0.1 to 0.6 mmol L-1 and from 10.0 to 50.0 mu mol.L-1. The calculated detection limit was 0.65 mu mol.L-1 in purified water, in the absence of supporting electrolyte, with relative standard deviation of 1.36% (n=6) for analyzing 10.0 mu mol L-1 nitrite solutions, and accuracy of 100.9 %, based on recovery studies. The application of this analytical method to mineral and river water samples of natural pH also showed improved sensitivity when compared with the linear sweep voltammetric method previously reported.

A solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica for differential pulse adsorptive stripping analysis of nickel in ethanol fuel

A solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica (SiAt-SPCPE) was applied to Ni2+ determination in commercial ethanol fuel samples. The proposed method comprised four steps: (1) Ni2+ preconcentration at open circuit potential directly in the ethanol fuel sample, (2) transference of the electrode to an electrochemical cell containing DMG, (3) differential pulse voltammogram registering and (4) surface regeneration by polishing the electrode. The proposed method combines the high Ni2+ adsorption capacity presented by 2-aminothiazole organofunctionalized silica with the electrochemical properties of the Ni(DMG)2 complex, whose electrochemical reduction provides the analytical signal.All experimental parameters involved in the proposed method were optimized. Using a preconcentration time of 20 min, it was obtained a linear range from 7.5 x 10(-9) to 1.0 x 10(-6) mol L-1 with detection limit of 2.0 x 10(-9) mol L-1. Recovery values between 96.5 and 102.4% were obtained for commercial samples spiked with 1.0 mu mol L-1 Ni2+ and the developed electrode was totally stable in ethanolic solutions. The contents of Ni2+ found in the commercial samples using the proposed method were compared to those obtained by graphite furnace atomic absorption spectroscopy by using the F- and t-test. Neither the F- nor t-values exceeded the critical values at 95% confidence level, confirming that there are not statistical differences between the results obtained by both methods. These results indicate that the developed electrode can be successfully employed to reliable Ni2+ determination in commercial ethanol fuel samples without any sample pretreatment or dilution step. (c) 2006 Elsevier B.V. All rights reserved.

Copper determination in ethanol fuel by differential pulse anodic stripping voltammetry at a solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica

Solid paraffin-based carbon paste electrodes modified with 2-aminothiazole organofunctionalized silica have been applied to the anodic stripping determination of copper ions in ethanol fuel samples without any sample treatment. The proposed method comprised four steps: (1) copper ions preconcentration at open circuit potential directly in the ethanol fuel sample; (2) exchange of the solution and immediate cathodic reduction of the absorbate at controlled potential; (3) differential pulse anodic stripping voltammetry; (4) electrochemical surface regeneration by applying a positive potential in acid media. Factors affecting the preconcentration, reduction and stripping steps were investigated and the optimum conditions were employed to develop the analytical procedure. Using a preconcentration time of 20 min and reduction time of 120 s at -0.3 V versus Ag/AgCl(sat) a linear range from 7.5 x 10(-8) to 2.5 x 10(-6) mol L(-1) with detection limit of 3.1 x 10(-8) mol L(-1) was obtained. Interference studies have shown a decrease in the interference effect according to the sequence: Ni > Zn > Cd > Pb > Fe. However, the interference effects of these ions have not forbidden the application of the proposed method. Recovery values between 98.8 and 102.3% were obtained for synthetic samples spiked with known amounts of Cu(2+) and interfering metallic ions. The developed electrode was successfully applied to the determination of Cu(2+) in commercial ethanol fuel samples. The results were compared to those obtained by flame atomic absorption spectroscopy by using the F-test and t-test. Neither F-value nor t-value have exceeded the critical values at 95% confidence level, confirming that there are no significant differences between the results obtained by both methods. (c) 2006 Elsevier B.V. All rights reserved.