Technology-enhanced learning as a site for interdisciplinary research

This briefing on Interdisciplinary Research is the fifth publication of its kind emerging from the Technology Enhanced Learning Research programme (TEL). TEL is a £12m programme running from 2007-2012 with eight large interdisciplinary projects aiming to combine technological and pedagogical expertise to improve outcomes for learners. The programme is funded jointly by the UK’s Economic and Social Research Council and Engineering and Physical Sciences Research Council. TEL also commissions analyses of key theoretical, practical and policy issues across and beyond the eight projects, and in the wider TEL field

Effects of low inoculum level of Meloidogyne incognita on cotton plants

Investigations on physiological responses of plants to nematode are usually carried out with plants inoculated with high number of eggs or second-stage juveniles. On the other hand, resistance against nematodes in plant breeding programs is evaluated with low number of inoculum. The aim of this research was to study some physiological responses of cotton plants inoculated with low inoculum levels of Meloidogyne incognita race 3. Two cultivars were used, Acala and IAC-20, susceptible and moderately resistant hosts respectively. Seedlings with 500 or 5,000 eggs were compared with control plants at 90 days post inoculation. The following aspects were assessed: shoot and root masses, photosynthesis, activity of the enzyme nitrate reductase, and chlorophyll and soluble sugar contents. At 90 days a water stress was imposed to some plants and the leaf water potentials determined. At 5,000 eggs, 'Acala' had a shoot reduction (leafmass). With 500 eggs, there was an estimulation of shoot growth in both cultivars, as revealed by a shootmass increase There was a clear increase on root growth of 'Acala' which was directly related to the inoculum levels. This response was probably caused by emission of new secondary roots and nematode galls formation. Chlorophyll and sugar content, and photosynthesis increased with the increase of inoculum levels, suggesting a response to support root growth in 'Acala'. In 'IAC-20' these higher values would be related with the energy demanded by defense mechanisms against the nematode. The imposed water stress caused a decrease on leaf water potential in 'IAC-20', but an increase in 'Acala' with increasing inoculum levels. The observed increase in the later cultivar might be related with the root growth, mainly due to emission of new secondary roots, while 'IAC 20' water stress response, would be considered as a pattern.Pesquisas acerca da fisiologia de plantas em resposta ao ataque de nematóides normalmente são feitas com doses altas de inóculo, quer sejam ovos ou juvenis de segundo estágio. Diferentemente, as avaliações da resistência de plantas a nematóides em programas de melhoramento são realizadas com doses bastante inferiores. Neste estudo acompanhou-se a variação de alguns parâmetros fisiológicos em algodão, em resposta à aplicação de baixas doses de inóculo de Meloidogyne incognita raça 3. Duas cultivares foram utilizadas, Acala e IAC-20, respectivamente suscetível e moderadamente resistente. Plântulas com duas folhas receberam 500 ou 5.000 ovos e, 90 dias depois, foram comparadas a plantas que não receberam o inóculo, quanto à massa da parte aérea e raízes, fotossíntese, atividade da enzima redutase do nitrato e teores de clorofila e açúcares solúveis. Aos 90 dias algumas plantas também foram submetidas à deficiência hídrica e o potencial da água determinado nas folhas. O maior nível de inóculo levou à redução da parte aérea (massa de folhas) em 'Acala'. Com 500 ovos parece ter ocorrido um estímulo em ambas as cultivares, uma vez que houve tendência de maior crescimento da parte aérea. Em 'Acala' houve maior crescimento de raiz com o aumento do inóculo, provavelmente devido à emissão de raízes secundárias nos pontos de penetração do nematóide e também pela formação de galhas. Houve aumento dos teores de clorofila e de açúcares solúveis, bem como da fotossíntese, com o aumento do inóculo. Discute-se se tal ocorrência deve-se à maior demanda de fotoassimilados para suportar o crescimento de raízes, em 'Acala'. Em IAC-20 esse fato estaria ligado aos mecanismos de defesa induzidos pelo ataque do nematóide. Após o estresse hídrico o potencial da água diminuiu em 'IAC-20' e aumentou na 'Acala', com o aumento do inóculo. A elevação do potencial da água, nesta última cultivar, poderia estar ligada ao crescimento das raízes e, principalmente, à emissão de novas raízes secundárias, ao passo que a resposta em 'IAC-20' seria a previsível, ou seja, de deficiência hídrica.192

La descentralización administrativa en la reforma constitucional plebiscitada en 1917

El trabajo analiza la importancia histórica del artículo 100 aprobado en el plebiscito constitucional de 1917, que regula la descentralización administrativa, los antecedentes de su creación, su desarrollo constitucional posterior y el estado de la cuestión al día de hoy

The Effects of Particular Sounds on Certain Indices of Cardio-pulmonary Functions

The purpose of this study was to identify the effects of particular sounds upon certain indices of cardio-pulmonary function and the degree and pattern of changes which occurred in the indices. The specific physiological parameters chosen to be monitored were heart rate, respiratory rate, mean tidal volume, instantaneous minute volume, and oxygen consumption. The hypothesis was that particular sounds will cause changes in certain indices of cardio-pulmonary functions. This was a controlled experiment, in which nine healthy males and nine healthy females, of a denominational, medically oriented University listened to a specially constructed tape of background music interspersed with an automobile accident, screaming, glass breaking, a siren, a bedpan dropping, jazz playing, an automobile horn and loud music. An EKG tracing and a Sandborn Metabulator tracing were made for each subject during the thirty-two minute testing period. A pilot study was done. T-tests were used to determine if changes of the variables were significant. T-tests indicated that, at the 0.05 level of significance, the dropping bedpan caused the only significant increases in heart rate of both males and females. The breaking glass caused a significant increase in the heart rate of the females only. Means and standard deviations of the variables of the male group and the female group showed that the heart rate of the males tended to increase during the period of breaking glass and decrease during the car crash. There was a slight downward trend in the respiratory rate for the males. Large individual differences were reflected in the standard deviations and substantiated by the raw data. The sound periods during which these large individual changes occurred and the parameters involved could have a clinical significance. There were no significant changes in the parameters from the control period of silence one in comparison to the silence two period which indicates there were no cumulative effects caused by the sequence of sounds. As a result of the findings of this study, the hypothesis was accepted. Particular sounds cause changes in certain indices of cardio-pulmonary functions

SUSTENTABILIDADE DO PERÍMETRO IRRIGADO JABIBERI

In the analyses of irrigation perimeters some fundamentalaspects are to be considered. This study takes the Jabibericase, a public irrigated perimeter in Sergipe State, evaluatingits soil condition, agricultural production, and irrigating profile,since its implantation in 1987 until the year 2000. In generalterms, that the sustainability of Jabiberi Irrigated Perimeterpresents as problems.O trabalho apresenta alguns indicadores de sustentabilidadepara avaliação de perímetros irrigados. Toma como estudode caso o Perímetro Irrigado Jabiberi, situado no Estado deSergipe, do tipo público e avalia as características do solo,da água, produção agrícola e perfil dos irrigantes, desde asua implantação em 1987 até 2000. Registra-se, em termosgerais, que a sustentabilidade do Perímetro Irrigado Jabiberiapresenta-se com problemas

Epithelial restitution in 3D - Revealing biomechanical and physiochemical dynamics in intestinal organoids via fs laser nanosurgery

Intestinal organoids represent a three-dimensional cell culture system mimicking the mammalian intestine. The application of single-cell ablation for defined wounding via a femtosecond laser system within the crypt base allowed us to study cell dynamics during epithelial restitution. Neighboring cells formed a contractile actin ring encircling the damaged cell, changed the cellular aspect ratio, and immediately closed the barrier. Using traction force microscopy, we observed major forces at the ablation site and additional forces on the crypt sides. Inhibitors of the actomyosin-based mobility of the cells led to the failure of restoring the barrier. Close to the ablation site, high-frequency calcium flickering and propagation of calcium waves occured that synchronized with the contraction of the epithelial layer. We observed an increased signal and nuclear translocation of YAP-1. In conclusion, our approach enabled, for the first time, to unveil the intricacies of epithelial restitution beyond in vivo models by employing precise laser-induced damage in colonoids

Sustainability of Jabiberi irrigated perimeter

O trabalho apresenta alguns indicadores de sustentabilidade para avaliação de perímetros irrigados. Toma como estudo de caso o Perímetro Irrigado Jabiberi, situado no Estado de Sergipe, do tipo público e avalia as características do solo, da água, produção agrícola e perfil dos irrigantes, desde a sua implantação em 1987 até 2000. Registra-se, em termos gerais, que a sustentabilidade do Perímetro Irrigado Jabiberi apresenta-se com problemas. _________________________________________________________________________________________ ABSTRACT: In the analyses of irrigation perimeters some fundamental aspects are to be considered. This study takes the Jabiberi case, a public irrigated perimeter in Sergipe State, evaluating its soil condition, agricultural production, and irrigating profile, since its implantation in 1987 until the year 2000. In general terms, that the sustainability of Jabiberi Irrigated Perimeter presents as problems