Avaliou-se o efeito da suplementação de eletrólitos sobre o desempenho de frangos, utilizando bicarbonato de sódio (NaHCO3) e cloreto de potássio (KCl) para ajuste do balanço eletrolítico da dieta (BED) com duas porcentagens de proteína bruta (PB). Utilizaram-se 800 frangos machos, alojados em 20 boxes, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos, cinco repetições e 40 aves por unidade experimental. Os tratamentos foram: dieta basal; dieta sem redução de PB suplementada com eletrólitos para ajuste do BED para 250mEq/kg; dieta com redução de PB, sem suplementação de eletrólitos; e dieta com redução de PB, com eletrólitos para ajuste do BED para 250mEq/kg. Foram avaliados: consumo da dieta, peso final, ganho de peso, ganho de peso médio diário, conversão alimentar e calórica e eficiência de utilização de nitrogênio e lisina nas fases de sete a 21 e de sete a 42 dias. Não se observaram diferenças (P>0,05) no consumo da dieta. A correção do BED com menor teor de PB melhorou (P<0,05) o peso final, na fase inicial. Houve piora (P<0,05) no ganho de peso e na conversão alimentar nas duas fases. A redução de três pontos percentuais na PB da dieta piorou o desempenho dos frangos.

The effect of the supplementation of electrolytes on de performance of broilers using sodium bicarbonate (NaHCO3) and potassium chloride (KC1) to adjust the electrolytic balance of the diet (BED) with two percentages of raw protein (PB) was studied. 800 male broiler chickens, housed in 20 boxes, distributed in random lineation, with four treatments, five repetitions and 40 birds per experimental unit were used. The treatments were: base diet; diet with no reduction of PB supplemented with electrolytes to adjust BED to 250mEq/kg; diet with a reduction of PB, with no electrolyte supplementation; and diet with the reduction of PB, with electrolytes to adjust the BED to 250mEq/kg. What was evaluated was: diet consumption, final weight, weight gain, average daily weight gain, food conversion and caloric efficiency of the use of nitrogen and lysine in phases from 7 to 21 and 7 to 42 days. No differences were observed (P>0.05) in diet consumption. The correlation of BED with the lower percentage of PB improved (P<0.05) the final weight in the initial phase. Weight gain and food conversion worsened (P<0.05) in both phases. The reduction of three percentage points in the PB in the diet worsened the broiler chicken's performance.

One hundred and sixty tambaqui fingerlings (Colossoma macropomum) (average weight of 11.01±2.08 g and total length of 7.8±0.18 cm) conditional in sixteen aquariums of 40 liters of water with temperature of 29.1±0.413ºC, density of stockage of 0.25 fingerling/l and constant aeration, with the objective to evaluate the amount of light in the productive performance of the fish. The treatments had consisted of the photoperiods: T1= 6 hours of light: 18 hours of dark (06HL:18HE), T2= 12HL:12HE, T3= 18HL:06HE and T4= 24HL: 0HE, with four repetitions each. The fingerling had been fed two times a day, with extrused commercial ration (28% of rude protein). The total volume of water was changed 40 times daily. To the end of 32 days, it was evaluated total length, standard length, height, consumption of ration, weight gain and survival. The results show that greater photoperiods had influenced positively the productive performance of tambaqui fingerlings.

Cento e sessenta alevinos de tambaqui (Colossoma macropomum) (peso médio de 11,01±2,08 g e comprimento total de 7,8±0,18cm) condicionados em dezesseis aquários de 40 litros de água com temperatura de 29,1±0,413ºC, densidade de estocagem de 0,25 alevinos/l e aeração constante, com o objetivo de avaliar a quantidade de luz no desempenho produtivo dos peixes. Os tratamentos consistiram dos fotoperíodos: T1= 6 horas de luz:18 horas de escuro (06HL:18HE), T2= 12HL:12HE, T3= 18HL:06HE e T4= 24HL:0HE, com quatro repetições cada. Os alevinos foram alimentados duas vezes ao dia, com ração comercial extrusada (28% de proteína bruta). Diariamente era trocado 40 vezes o volume total da água. Ao final de 32 dias, foi avaliado comprimento total, comprimento padrão, altura, consumo de ração, ganho de peso e sobrevivência. Os resultados demonstraram que os maiores fotoperíodos influenciaram de forma positiva o desempenho produtivo dos alevinos de tambaqui.

The microstructural evolution of the CuZnAl shape memory alloys was studied by indirect techniques relating to the atomic migration rate of grain boundaries. Addition elements were used in a Cu-15,5Zn-8,0Al alloy to provide a comparison with the same alloy without microelement additions. The alloys were melted in an induction furnace of 24 kVA. After casting, the bulk samples of the alloys were homogenized. Then they were solution treated and hot-rolled followed by water-quenching to initiate the recrystallization. Finally, annealing produced at different temperature ranges was made in different samples in order to establish a law for the grain growth. Following the heat treatments, all annealed samples were examined by statistical metallography and the grain sizes were measured. After measurements, the same empirical law of grain growth was found for the different alloys and the ln [D-Do] x 1/T diagrams were plotted in order to establish the kinetic behavior. Based on the estimated values of the activation energy, important conclusions were obtained concerning the addition elements.

OBJETIVOS: A proposta deste trabalho é investigar o perfil socioeconômico, o motivo de estudar medicina, a opção por especialidade e residência médica e a preferência em trabalhar como profissional liberal ou assalariado entre os estudantes de medicina da Universidade Federal de Minas Gerais (UFMG). MÉTODO: Durante o ano de 1997, realizou-se estudo comparativo entre os estudantes de medicina da UFMG do 5º período, iniciando o ciclo clínico, e aqueles do internato, terminando o ciclo clínico. Como instrumento foi utilizado um questionário distribuído a todos alunos das duas turmas. RESULTADOS: Houve grande semelhança entre os estudantes de 5º período e os do internato. Em torno de 50% dos estudantes eram do sexo feminino, mais da metade procedeu da capital do Estado, em Belo Horizonte, nasceu em família pequena com menos de três filhos, foi aprovada no primeiro vestibular e o pai cursou escola superior. A renda familiar situou-se entre 10 e 50 salários em 2/3 dos casos. Estes dados são compatíveis com a origem de classe média alta, embora em aproximadamente 12% a renda familiar foi inferior a 10 salários. A grande maioria estudou medicina por vocação ou altruísmo (80%), raramente por questões de mercado (<5%). Houve grande preferência pela medicina como profissão liberal (98%), mas em torno de 80% aceitaria o emprego público como alternativa. Quase todos (98%) pretendiam fazer residência médica e se tornar especialistas, poucos (<20%) indicaram entre estas as especialidades de área geral, como clínica médica, gineco-obstetrícia, pediatria e cirurgia. CONCLUSÃO: O estudo mostrou perfil socioeconômico relativamente elevado do estudante de medicina da UFMG e preferência pela prática especializada da medicina.

OBJECTIVE: this study was made with the medical students of the "Universidade Federal de Minas Gerais" (UFMG), to get their social economic profile, and their reasons for studying medicine, choosing the specialty, doing medical residence, and showing preferences for being a liberal professional or a salaried employee. METHODS: In 1997, a study was made comparing UFMG's medical students beginning their clinical practice (5th semester) and those medical students during the internship in the last term of clinical practice. Both groups were given questionnaires for evaluation. RESULTS: The results were similar for both groups and showed that women constituted almost 50% of the students and about 50% of them were from Belo Horizonte, the State capital of Minas Gerais, Brazil, and from small families with less than three children, and whose parents held a college degree. These students passed the college entrance exams on their first try. Two thirds of their families had income of about 10 to 50 Brazilian minimum wages, and approximately 12% of the families had an income of less than 10 minimum wages. The majority of the students decided to study medicine for altruism or vocational reason; very few (<5%) chose to study medicine for financial reasons. Almost all students (98%) preferred a liberal medical practice; however 80% would accept civil-service employment as an alternative. Nearly all of them (98%) chose to do medical residence to specialize. Most students would prefer to be specialists and only less than 20% would prefer to do general practice in areas such as adult and pediatric clinic, gynecology-obstetric and general surgery. CONCLUSION:. This study shows that medical students from UFMG have an elite social economic profile and a preference for specialized medical practice.