RESUMEN Las virosis son la principal limitante del rendimiento de batata, quinto cultivo alimenticio del mundo. En Argentina, el “encrespamiento amarillo” (EA), complejo viral con siete agentes involucrados, causa notables pérdidas en los genotipos de toda región productiva. Se analizó la influencia del EA en componentes de rendimiento de los cvs Arapey INIA y Beauregard. mediante ensayos comparativos que combinaron dos condiciones sanitarias (sana vs enferma) y dos genotipos. Las plantas sanas se obtuvieron por termoterapia y cultivo in vitro de meristemas, y las enfermas, injertando púas con EA. Hubo diferencias significativas entre condiciones sanitarias, en contenido de clorofilas y mermas en caracteres de rendimiento cercanas al 90%, donde peso y número de raíces comerciales fueron los más afectados por EA en ambas variedades. Se corrobora la relevancia del EA como limitante del cultivo y del empleo de materiales saneados junto a buenas prácticas de manejo para alcanzar rendimientos potenciales.

SUMMARY Virus diseases are the main constraint of sweet potato yield, the fifth largest food crop. In Argentina, “yellow curling” (EA), a viral complex with seven agents involved, causes notable losses in all the growing regions. The influence of EA on yield components of Arapey INIA and Beauregard cultivars was analyzed by comparative trials that combined two health conditions and two genotypes. Healthy plants were obtained by thermotherapy and in vitro culture of meristems and the diseased ones, by grafting with EA. There were significant differences between health conditions, in chlorophyll content and losses in yield characters near to 90%. Weight and number of commercial roots were the most affected by EA in both cultivars. This work corroborates the relevance of EA on sweet potato production. Virus free plants and good management practices increase greatly the yields.

BACKGROUND: Selection of medical students at South African (SA) medical schools must promote equitable and fair access to students from all population groups, while ensuring optimal student throughput and success, and training future healthcare practitioners who will fulfil the needs of the local society. In keeping with international practices, a variety of academic and non-academic measures are used to select applicants for medical training programmes in SA medical schools. OBJECTIVES: To provide an overview of the selection procedures used by all eight medical schools in SA, and the student demographics (race and gender) at these medical schools, and to determine to what extent collective practices are achieving the goals of student diversity and inclusivity. METHODS: A retrospective, quantitative, descriptive study design was used. All eight medical schools in SA provided information regarding selection criteria, selection procedures, and student demographics (race and gender). Descriptive analysis of data was done by calculating frequencies and percentages of the variables measured. RESULTS: Medical schools in SA make use of academic and non-academic criteria in their selection processes. The latter include indices of socioeconomic disadvantage. Most undergraduate medical students in SA are black (38.7%), followed by white (33.0%), coloured (13.4%) and Indian/Asian (13.6%). The majority of students are female (62.2%). The number of black students is still proportionately lower than in the general population, while other groups are overrepresented. CONCLUSION: Selection policies for undergraduate medical programmes aimed at redress should be continued and further refined, along with the provision of support to ensure student success.

RESUMODiversidade genética de Mycoplasma hyopneumoniae tem sido relatada em análise múltipla de repetições em tandem em número variável (MLVA). O objetivo deste estudo foi descrever a distribuição espacial e a heterogeneidade genética de tipos de M. hyopneumoniae no Brasil, bem como investigar a correlação entre regiões de repetição 1 (RR1) e 3 (RR3) de duas adesinas importantes (P97 e P146). Foram identificados 39 tipos de MLVA baseados no número de repetições em tandem em P97 RR1 e RR3 P146. A correlação negativa significativa (Spearman's rho = -0,26; P = 0,022) entre P97 RR1 e RR3 P146 foi observada, o que sugere um possível mecanismo compensatório que permitiria a bactéria manter a sua capacidade de adesão. Os resultados contribuem para compreender a epidemiologia das M. hyopneumoniae no quarto maior país produtor de suínos do mundo.

Detection of failures in induction motors is one of the most important concerns in industry. An unexpected fault in the induction motors can cause a loss of financial resources and waste of time that most companies cannot afford. The contribution of this paper is a fusion of the Empirical Mode Decomposition (EMD) and Multiple Signal Classification (MUSIC) methodologies for detection of multiple combined faults which provides an accurate and effective strategy for the motor condition diagnosis.

Micro displacements are measured with holographic gratings by using a grating interferometer of one order that detects the phase changes in the diffracted orders caused by movement of the grooves in the diffraction gratings. The period can be on the order of fractions of a micron, with high reproducibility and an error of a half period. The basic operating principle involves the superposition of order +1, with order 0. The interferometer system produces standing waves; it works by measuring the intensity variations at the center of a ring-shaped interference pattern, which indicate the phase shift introduced by displacement of the grating grooves. When these rings move to the center of the pattern or to the border, the direction of the grating displacement can be detected; the interferometer system has no moving parts, except for the diffraction grating, and is very stable and robust. This system has the ability to measure micro displacements even with damaged gratings, as long as the gratings diffract evenly.

The refractory degradation on induction furnace walls at different points was studied. A SiO2 (98.8%) base refractory was analyzed with two different slag chemical composition through crucible and dipping laboratory degradation test and also applying an asymmetric modeling. The slag, refractory structure and slag penetration was analyzed by optical microscopy using reflecting light technique. The results demonstrated that slag penetration starts on the refractory pores produced by the sintering process and also by hollows generated by the came off grains. The modeling results evidenced that, with high frequency (240 Hz), a high Lorentz force (14.26 N) is originated but with a low liquid velocity (6 m/s) that have a perpendicular vector direction to the furnace walls, making pressure over the filtered slag.

En este trabajo de investigación se realizó un estudio de la degradación atípica que se produce en las paredes de los hornos de inducción. Para esto, se utilizó un material refractario base - SiO2 (98.8%) con dos escorias de composición química diferente y se analizó su comportamiento mediante las pruebas experimentales del método de copa o crisol y el de inmersión, así como por un modelado asimétrico del metal líquido en el horno de inducción. La escoria, la estructura del material refractario y el mecanismo de penetración de la escoria fueron caracterizados por microscopia óptica, utilizando la técnica de luz reflejada. Los resultados demostraron que, con valores altos de frecuencia (240 Hz), para la operación del horno, se obtiene una fuerza de Lorentz muy alta (14.26 N) pero con una velocidad del metal liquido baja (6 m/s) la cual tiene un vector de dirección perpendicular a las paredes del horno, provocando presión sobre la escoria incrustada en los poros del refractario favoreciendo el proceso de degradación del material.

Foi determinada a prevalência de Ehrlichiose canina entre animais atendidos no Complexo Hospitalário Veterinário do Corozal da Faculdade de Medicina Veterinária da Universidade de Panamá. O levantamento foi realizado de forma retrospectiva com dados obtidos no período de janeiro de 2004 a dezembro de 2009. Para o trabalho, foram utilizados os registros dos casos clínicos de ehrlichiose canina, confirmados através de esfregaço sanguíneo, a raça e os aspectos demográficos (idade, sexo e local de origem) de cada animal. Os resultados revelaram que 10,12% dos animais atendidos (n = 1.452) mostraram-se positivos para o problema no período em análise. Esses animais eram de ambos os sexos com idade media de aproximadamente 3,6 anos. A prevalência mensal registrada foi de 9,98%, com taxa de infecção significativamente superior em 2008 (14,83%). O número de casos positivos foi significativamente superior nos meses de março, maio e setembro e menor no mês de fevereiro, destacando-se haver densidade de casos igual ou superior à média de maio a outubro. A raça e o local de origem dos animais foram identificados como fatores de risco.

The aim of this study was to determine the prevalence of canine Ehrlichiosis among animals treated at the Corozal Veterinary Hospital of the Faculty of Veterinary Medicine, University of Panama, Brazil. The survey was conducted retrospectively with data obtained from January 2004 to December 2009, based on the records of clinical cases of canine ehrlichiosis, confirmed with blood smear, race and demographics data (age, sex and place of origin) of each animal. The results revealed that 10.12% of the treated animals (n = 1452) were positive in the period under review. These animals were of both sexes with a mean age of approximately 3.6 years. The monthly prevalence recorded was 9.98%, with a significantly higher infection rate in 2008 (14.83%). The positive cases were significantly higher in the months of March, May and September and lowest in February, with a noteworthy density of cases equal to or higher than the average from May to October. Breed and place of origin of the animals were identified as risk factors.

South Africa has a 'quadruple burden of disease'. One way to reduce this burden, and address the social determinants of health and social inequity, could be through health promotion interventions driven by an independent Health Promotion and Development Foundation (HPDF). This could provide a framework to integrate health promotion and social development into all government and civil society programmes. On priority issues, the HPDF would mobilise resources, allocate funding, develop capacity, and monitor and evaluate health promotion and development work. Emphasis would be on reducing the effects of poverty, inequity and unequal development on disease rates and wellbeing. The HPDF could also decrease the burden on the proposed National Health Insurance (NHI) system. We reflect on such foundations in other countries, and propose a structure for South Africa's HPDF and a dedicated funding stream to support its activities. In particular, an additional 2% levy on alcohol and tobacco products is proposed to be utilised to fund the HPDF.

OBJECTIVE: Reflecting on its role during apartheid, the Faculty of Health Sciences of the University of Cape Town (UCT) undertook a study to explore the experiences of black alumni who trained in the period 1945 - 1994. DESIGN: Seventy-five black alumni were selected through purposive and snowball recruitment, resulting in 52 face-to-face and 23 telephonic or postal interviews. RESULTS: Experiences of racial discrimination were widely reported and respondents believed the quality of their training was adversely affected. Until 1985, black students were required to sign a declaration agreeing to excuse themselves from classes where white patients were present. Black students were denied access to white patients in wards, and the university admitted that it could not guarantee their clinical training. Tutorial groups were racially segregated. Black students were also excluded from university facilities, events and extramural activities. Themes that emerged were: lack of social contact with white staff and students during training, belief that white staff members actively or tacitly upheld discriminatory regulations, and resistance by black students. Efforts of some white staff to resist discrimination were acknowledged. CONCLUSION: Racism was entrenched explicitly and implicitly. Perceptions of the attitudes of white staff to apartheid legislation on the part of black alumni were diverse, ranging from claims of active support for racial discrimination to recognition of attempts to resist racist rules. These findings provided the basis for Faculty transformation initiatives based on human rights, respect for human dignity and non-discrimination.

Os autores apresentam 6 casos de blastomicose sul americana, 2 casos de actinomicose, 1 caso de rinosporidiose, 1 de cromoblastomicose e 1 caso de criptococose, estudando os respectivos cogumelos responsáveis, pela coloração empregando o ácido periódico-Schiff. As vantagens dêste método para identificação e estudo morfológico são evidenciadas pelas microfotografias apresentadas.

The authors present 6 cases of south american blastomycosis, 2 cases of actinomycosis, 1 case of rhinosporidiosos, 1 case of chromoblastomycosis and one case of cryptococcosis. They study the respective fungi employing the periodic-acid-Schiff reaction. The advantages of this method for identification and morphologic studies are seen through the photomicrographs in this paper.