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The biosorption of lead(II) and chromium(VI) on groundnut hull was investigated. Batch biosorption experiments were conducted to find the equilibrium time and biosorption capacity. Effect of parameters like pH, temperature and initial metal concentration was studied. The maximum biosorption capacity of lead(II) and chromium(VI) was found to be 31.54 +/- 0.63 and 30.21 +/- 0.74 mg g-1, respectively. The optimum pH for lead(II) and chromium(VI) removal was 5 ± 0.1 and 2 +/- 0.1, respectively. The temperature change, in the range of 20 - 45ºC affected the biosorption capacity. The maximum removal of lead(II) was achieved at 20 +/- 2ºC, where as maximum uptake of chromium(VI) was observed at 40 +/- 2ºC. The biosorption data was fitted to the Langmuir and the Freundlich isotherm models. The Langmuir model showed better representation of data, with correlation coefficient greater than 0.98. The kinetics of biosorption followed the pseudo second order kinetics model. The thermodynamics parameters were evaluated from the experimental data.

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Foram realizados dois experimentos para se determinar as exigências de cálcio para melhor desempenho e deposição de cálcio (Ca) e fósforo (P) na tíbia e no fêmur de codornas japonesas, no período de um a 35 dias de idade. Utilizaram-se, em cada experimento, 210 codornas fêmeas, distribuídas num delineamento experimental inteiramente casualizado, constituído de sete tratamentos, com três repetições e dez aves por unidade experimental. Os tratamentos consistiram numa ração basal suplementada com calcário calcítico para atingir os níveis de 0,85; 1,00; 1,15; 1,30; 1,45; 1,60 e 1,75% de Ca para a fase inicial (1 a 21 dias) e de 0,53; 0,68; 0,83; 0,98; 1,13; 1,28 e 1,43% de Ca para a fase de crescimento (22 a 35 dias). Foi verificado efeito quadrático dos níveis de Ca da dieta sobre o consumo de ração, o ganho de peso e a conversão alimentar na fase inicial, bem como sobre o teor de Ca na tíbia e no fêmur das codornas aos 21 dias de idade. Na fase de crescimento, apenas a conversão alimentar foi influenciada pelos níveis de Ca da dieta. Recomendam-se 1,26 e 0,87% de Ca nas dietas para codornas nas fases inicial e de crescimento, respectivamente .(AU)

Two trials were carried out to determine calcium requirements for better performance, and calcium (Ca) and phosphorus (P) deposition in the tibia and femur of Japanese quails aged 1 to 35 days. Two hundred and ten female quails were allocated in a completely randomized experimental design, with seven treatments, three repetitions and ten birds per experimental unit. The treatments consisted of a basal diet supplemented with limestone in order to produce the following Ca levels: 0.85; 1.00; 1.15; 1.30; 1.45; 1.60 and 1.75% in the initial phase (1 to 21 days) and 0.53; 0.68; 0.83; 0.98; 1.13; 1.28 and 1.43% in the growing phase (22 to 35 days). In the initial phase, feed intake, weight gain and feed conversion showed quadratic response to dietary Ca levels, as well as on the content of Ca in the tibia and femur of quails. In the growing phase, only feed conversion was significantly affected. Dietary calcium levels recommended for the initial and growing phases are 1.26 and 0.87%, respectively.(AU)

Assuntos

RESUMO

Foram realizados dois experimentos para se determinar as exigências de cálcio para melhor desempenho e deposição de cálcio (Ca) e fósforo (P) na tíbia e no fêmur de codornas japonesas, no período de um a 35 dias de idade. Utilizaram-se, em cada experimento, 210 codornas fêmeas, distribuídas num delineamento experimental inteiramente casualizado, constituído de sete tratamentos, com três repetições e dez aves por unidade experimental. Os tratamentos consistiram numa ração basal suplementada com calcário calcítico para atingir os níveis de 0,85; 1,00; 1,15; 1,30; 1,45; 1,60 e 1,75% de Ca para a fase inicial (1 a 21 dias) e de 0,53; 0,68; 0,83; 0,98; 1,13; 1,28 e 1,43% de Ca para a fase de crescimento (22 a 35 dias). Foi verificado efeito quadrático dos níveis de Ca da dieta sobre o consumo de ração, o ganho de peso e a conversão alimentar na fase inicial, bem como sobre o teor de Ca na tíbia e no fêmur das codornas aos 21 dias de idade. Na fase de crescimento, apenas a conversão alimentar foi influenciada pelos níveis de Ca da dieta. Recomendam-se 1,26 e 0,87% de Ca nas dietas para codornas nas fases inicial e de crescimento, respectivamente .

Two trials were carried out to determine calcium requirements for better performance, and calcium (Ca) and phosphorus (P) deposition in the tibia and femur of Japanese quails aged 1 to 35 days. Two hundred and ten female quails were allocated in a completely randomized experimental design, with seven treatments, three repetitions and ten birds per experimental unit. The treatments consisted of a basal diet supplemented with limestone in order to produce the following Ca levels: 0.85; 1.00; 1.15; 1.30; 1.45; 1.60 and 1.75% in the initial phase (1 to 21 days) and 0.53; 0.68; 0.83; 0.98; 1.13; 1.28 and 1.43% in the growing phase (22 to 35 days). In the initial phase, feed intake, weight gain and feed conversion showed quadratic response to dietary Ca levels, as well as on the content of Ca in the tibia and femur of quails. In the growing phase, only feed conversion was significantly affected. Dietary calcium levels recommended for the initial and growing phases are 1.26 and 0.87%, respectively.

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Viscosity and elasticity are the fundamental rheologic properties of respiratory mucus, and are important determinants of transportability of mucus in the mucociliary system. One technique that permits to monitor indirectly the rheologic properties of any sample is the photoacoustic technique. Using that technique, the absorption of isotonic saline solution by human mucus was monitored. The mucus was obtained from 11 volunteers, divided into two groups: five volunteers presenting pneumology symptoms (group I) and six healthy volunteers (group II). The photoacoustic signal of the mucus absorbing the saline solution was monitored as function of time, with measurements being performed each 10 min, up to 120 min. The resulting curves were fitted to sigmoidal curves to simulate the evolution on time of the photoacoustic signal. A characteristic time for the half saturation of the absorption process was obtained. For group I the time obtained was 23.3+/-5.3 min and for group II the time obtained was 55.0+/-7.7 min, both means being significantly different (Student t-test, p<0.05). This result supports the empirical practice of treating individuals presenting symptoms of airway obstruction with about 30 min of inhalations of isotonic saline solution vapor for the clearance of the airways.

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Physiological studies of the mussel Perna perna in Brazil are almost 30 years behind those of other, more exhaustively investigated species, such as Mytilus edulis. Little is known about the variations in physiological rates due to size and the consequences of maintaining P. perna in laboratory conditions. This work investigated the variations in respiration, clearance, excretion and absorption efficiency rates of P. perna, classified by size and acclimatized in a laboratory, monitoring the mussels respiration rates and biometry over a period of 30 days, in laboratory conditions. The respiration, clearance and excretion rates presented an allometric relation with the dry weight of the organisms, with b values of 0.66, 0.48 and 0.91 respectively. On the other hand, these same rates, when considered by weight (specific rates) showed a relationship that was inverse to the size of the organisms. Only the absorption efficiency was independent of the weight of the mussel. In terms of acclimatization, it was observed that it takes 10 days for the respiration rate of the mussel P. perna to stabilize in laboratory conditions, after which it follows a routine metabolism.

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A absorção de fármacos a partir de formas farmacêuticas sólidas, administradas por via oral, depende de sua liberação, da dissolução ou solubilização dos mesmos em condições fisiológicas e da permeabilidade das membranas do trato gastrintestinal. Portanto, a dissolução in vitro é fundamental para se prever o desempenho in vivo do fármaco. Pretendeu-se neste trabalho, realizar avaliação biofarmacotécnica in vitro através de testes físico-químicos e avaliação da cinética e eficiência de dissolução de quatro lotes de duas formulações do mercado nacional contendo 100mg de doxiciclina. Utilizou-se o método descrito pela Farmacopéia Americana para realização do ensaio de dissolução. A análise da cinética de dissolução foi avaliada por meio dos parâmetros...

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Changes induced by mutations in rhodopsin that are associated with the degenerative visual disease retinitis pigmentosa result in an altered pattern of light absorption according to quantum mechanical simulations and reference experimental works. Eleven single-point mutations associated with retinitis pigmentosa at and in the proximity to the retinal binding pocket of rhodopsin have been modeled in silico and their spectra calculated with the NDOL (Neglect of Differential Overlap accounting L azimuthal quantum number) a priori method. The altered pattern of absorption found would lead to cumulative consequences in energy dissipation with aging. Different energy balances in the case of mutants at the very molecular level, compared to native nonmutated rhodopsin, can cause permanent cellular stress and would play a role in the progression of the retine degenerative process. It could explain the worsening of the pathological condition mostly in adults and suggests the probable beneficial effects of using quenching drugs and protection devices against excess of light in the early stages of life for avoiding or reducing potential damage.

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