987 resultados para Black flies, mosquitoes, diet, nectar, honeydew.


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Contends that South African universities must find admissions criteria, other than high school grades, that are both fair and valid for Black applicants severely disadvantaged by an inferior school education. The use of traditional intellectual assessments and aptitude tests for disadvantaged and minority students remains controversial as a fair assessment; they do not take account of potential for change. In this study, therefore, a measure of students' cognitive modifiability, assessed by means of an interactive assessment model, was added as a moderator of traditional intellectual assessment in predicting 1st-yr university success. Cognitive modifiability significantly moderated the predictive validity of the traditional intellectual assessment for 52 disadvantaged Black students. The higher the level of cognitive modifiability, the less effective were traditional methods for predicting academic success and vice versa.

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Examining the late style of a writer is like skirting around quicksand. End-of-career reflection can subvert long standing critical accounts; revisionist publishing histories or newly minted archival work can do likewise. And, as Nancy J. Troy suggests, an artist’s last thoughts are rarely planned as such (15). In the case of Christina Stead any consideration of late style is made more difficult because, chronologically speaking, her ‘late’ works were written some 20 years before her death in 1983. Thus chronology can be deceptive, as Nicholas Delbanco points out in Lastingness: The Art of Old Age. Stead’s last novel, I’m Dying Laughing The Humourist, was completed, at least in rough draft form in 1966, when Stead was 64, but friends and readers suggested many changes. The book was published posthumously in 1986. Stead’s work is receiving increasing critical attention so a discussion of her ‘late style’ is important, particularly given that her fiction seems to refuse so many attempts at category-making. This perspective reveals two interesting aspects of her late work: first her consistent engagement with the problems of age for women, and in particular women writers, and second, the consequence of a life-long attention to the representation of dialogic sound in her novels, a preoccupation that results in what can be termed an aural signature. My discussion refers to Edward Said’s and Nicholas Delbanco’s ideas about late style by way of a focus on selective biographical issues and Stead’s engagement with radical politics before moving to an examination of what can be called an aural signature in several novels. Her fiction demonstrates one of the agreed markers of late style: she was constantly looking forward and looking back through innovation in form and content.

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This chapter discusses an action research project into the lived experience of the workplace mobbing phenomenon. The action research methodology is based on the exemplarian model (Coenen & Khonraad, 2003) from the Netherlands Group. This model requires positive outcomes for those immersed in the problem to reduce the adversity of their circumstances. The findings challenge the psychological perspective of the existing bullying literature that tends to focus on individual behaviour. This research, undertaken over a three year period with 212 participants, identified the dysfunctional nature of public sector bureaucracies and the power gained through gossip and rumour as some of the key emergent themes to explain the workplace mobbing problem. In addition, resistance, conscientisation, and agency were identified as the key to transformation for those targeted. The discussion focuses on the crystallisation phase of the exemplarian model where the participants identified themselves as the Black Sheep and adopted the motto that “a black sheep is a biting beast” (Bastard, 1565 or 6-1618, p. 90), reflecting a sense of empowerment, individual agency, and a sense of humour in dealing with the serious yet seemingly absurd reality of their situations. The identity of the Black Sheep was consolidated when the group organised a 2 day conference with over 200 attendees to discuss how best to prevent workplace mobbing. This self-affirming action was a proactive step towards metaphorically “biting back” at the problem. A number of positive outcomes were achieved including the conference with over 200 attending leading to national media coverage across Australia and additional interviews with magazines, newspapers, and radio.

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Determining the optimal of black-start strategies is very important for speeding the restoration speed of a power system after a global blackout. Most existing black-start decision-making methods are based on the assumption that all indexes are independent of each other, and little attention has been paid to the group decision-making method which is more reliable. Given this background, the intuitionistic fuzzy set and further intuitionistic fuzzy Choquet integral operator are presented, and a black-start decision-making method based on this integral operator is presented. Compared to existing methods, the proposed algorithm cannot only deal with the relevance among the indexes, but also overcome some shortcomings of the existing methods. Finally, an example is used to demonstrate the proposed method. © 2012 The Institution of Engineering and Technology.

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The effect of plasma taken from normotensive humans, while on a low and high sodium diet, on [Na + K]-ATPase and 3H-ouabain binding was measured in tubules from guinea-pig kidneys. Plasma from the high sodium, compared to the low sodium, diet period: (a) inhibited [Na + K]-ATPase activity; (b) decreased 3H-ouabain affinity for binding sites; (c) increased the number of available 3H-ouabain binding sites; (d) decreased [Na + K]-ATPase turnover (activity/3H-ouabain binding sites). The inhibition of [Na + K]-ATPase suggests an increase in a (possible) natriuretic factor. The decreased affinity of 3H-ouabain binding suggests an endogenous ouabainoid, which may be the natriuretic factor.

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Objective: We investigated to what extent changes in metabolic rate and composition of weight loss explained the less-than-expected weight loss in obese men and women during a diet-plus-exercise intervention. Design: 16 obese men and women (41 ± 9 years; BMI 39 ± 6 kg/m2) were investigated in energy balance before, after and twice during a 12-week VLED (565–650 kcal/day) plus exercise (aerobic plus resistance training) intervention. The relative energy deficit (EDef) from baseline requirements was severe (74-87%). Body composition was measured by deuterium dilution and DXA and resting metabolic rate (RMR) by indirect calorimetry. Fat mass (FM) and fat-free mass (FFM) were converted into energy equivalents using constants: 9.45 kcal/gFM and 1.13 kcal/gFFM. Predicted weight loss was calculated from the energy deficit using the '7700 kcal/kg rule'. Results: Changes in weight (-18.6 ± 5.0 kg), FM (-15.5 ± 4.3 kg), and FFM (-3.1 ± 1.9 kg) did not differ between genders. Measured weight loss was on average 67% of the predicted value, but ranged from 39 to 94%. Relative EDef was correlated with the decrease in RMR (R=0.70, P<0.01) and the decrease in RMR correlated with the difference between actual and expected weight loss (R=0.51, P<0.01). Changes in metabolic rate explained on average 67% of the less-than-expected weight loss, and variability in the proportion of weight lost as FM accounted for a further 5%. On average, after adjustment for changes in metabolic rate and body composition of weight lost, actual weight loss reached 90% of predicted values. Conclusion: Although weight loss was 33% lower than predicted at baseline from standard energy equivalents, the majority of this differential was explained by physiological variables. While lower-than-expected weight loss is often attributed to incomplete adherence to prescribed interventions, the influence of baseline calculation errors and metabolic down-regulation should not be discounted.

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The common brown leafhopper Orosius orientalis (Hemiptera: Cicadellidae) is a polyphagous vector of a range of economically important pathogens, including phytoplasmas and viruses, which infect a diverse range of crops. Studies on the plant penetration behaviour by O. orientalis were conducted using the electrical penetration graph (EPG) technique to assist in the characterisation of pathogen acquisition and transmission. EPG waveforms representing different probing activities were acquired from adult O. orientalis probing in planta, using two host species, tobacco Nicotiana tabacum and bean Phaseolus vulgaris, and in vitro using a simple sucrose-based artificial diet. Five waveforms (O1–O5) were evident when O. orientalis fed on bean, whereas only four waveforms (O1–O4) and three waveforms (O1–O3) were observed when the leafhopper fed on tobacco and on the artificial diet, respectively. Both the mean duration of each waveform and waveform type differed markedly depending on the food substrate. Waveform O4 was not observed on the artificial diet and occurred relatively rarely on tobacco plants when compared with bean plants. Waveform O5 was only observed with leafhoppers probing on beans. The attributes of the waveforms and comparative analyses with previously published Hemipteran data are presented and discussed, but further characterisation studies will be needed to confirm our suggestions.

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Dengue virus is the most significant human viral pathogen spread by the bite of an infected mosquito. With no vaccine or antiviral therapy currently available, disease prevention relies largely on surveillance and mosquito control. Preventing the onset of dengue outbreaks and effective vector management would be considerably enhanced through surveillance of dengue virus prevalence in natural mosquito populations. However, current approaches to the identification of virus in field-caught mosquitoes require relatively slow and labor intensive techniques such as virus isolation or RT-PCR involving specialized facilities and personnel. A rapid and portable method for detecting dengue virus-infected mosquitoes is described. Using a hand held battery operated homogenizer and a dengue diagnostic rapid strip the viral protein NS1 was detected as a marker of dengue virus infection. This method could be performed in less than 30 min in the field, requiring no downstream processing, and is able to detect a single infected mosquito in a pool of at least 50 uninfected mosquitoes. The method described in this study allows rapid, real-time monitoring of dengue virus presence in mosquito populations and could be a useful addition to effective monitoring and vector control responses.

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Overconsumption is commonly implicated in the aetiology of obesity; however there is a lack of consensus on a definition and the most appropriate methodology for assessing it. The aim of this communication is to highlight the need for theoretical consensus on the assessment of overconsumption, which may lead to improved methodological standards in obesity research. In laboratory studies, overconsumption is most frequently inferred from the comparison of food intake within or between individuals against a single control. Measurement often relies on a single eating episode with limited consideration of preceding or subsequent intake. An alternative approach is to consider food intake in the context of energy requirements, within an energy balance framework. One such marker of chronic overconsumption is body weight. There is a need for agreement on the definition and measurement of overconsumption, so that its role in weight gain and obesity can be more precisely delineated.

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In many countries, governments and health agencies are strongly promoting physical activity as a means to prevent the accumulation of fatness that leads to weight gain and obesity. However, there is often a resistance to respond to health promotion initiatives. For example, in the UK, the Chief Medical Officer has recently reported that 71% of women and 61% of men fail to carry out even the minimal amount of physical activity recommended in the government’s guidelines. Similarly, the Food safety Agency has promoted reductions in the intake of fat, sugar and salt but with very little impact on the pattern of consumption. Why is it that recommendations to improve health are so difficult to implement, and produce the desired outcome?

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Traditionally, Science education has stressed the importance of teaching students to conduct ‘scientific inquiry’, with the main focus being the experimental model of inquiry used by real world scientists. Current educational approaches using constructivist pedagogy recognise the value of inquiry as a method for promoting the development of deep understanding of discipline content. A recent Information Learning Activity undertaken by a Grade Eight Science class was observed to discover how inquiry based learning is implemented in contemporary Science education. By analysing student responses to questionnaires and assessment task outcomes, the author was able to determine the level of inquiry inherent in the activity and how well the model supported student learning and the development of students’ information literacy skills. Although students achieved well overall, some recommendations are offered that may enable teachers to better exploit the learning opportunities provided by inquiry based learning. Planning interventions at key stages of the inquiry process can assist students to learn more effective strategies for dealing with cognitive and affective challenges. Allowing students greater input into the selection of topic or focus of the activity may encourage students to engage more deeply with the learning task. Students are likely to experience greater learning benefit from access to developmentally appropriate resources, increased time to explore topics and multiple opportunities to undertake information searches throughout the learning activity. Finally, increasing the cognitive challenge can enhance both the depth of students’ learning and their information literacy skills.

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Food insecurity is the limited availability of, or access to, sufficient amounts of nutritious, culturally-appropriate and safe foods, or the inability to access such foods by socially-acceptable means. Evidence from the United States and Canada suggests that food insecurity may be associated with poor dietary intakes, obesity, and chronic disease including depression and diabetes, thus constituting a significant public health issue. Currently, no existing studies have investigated the dietary and health factors associated with food insecurity among the general Australian population. The current study investigated the potential associations between food insecurity, diet and health among Australian adults (18 years and over) participating in the cross-sectional National Health Survey (n = 19,500). Data were analysed by logistic regression adjusting for sociodemographic covariates. Those from food insecure households were 50% less likely to consume the recommended number of servings of fruit, 60% more likely to report poor health and experienced a 6-fold increase in the risk of severe depressive disorders, compared to their food secure counterparts. Furthermore, food insecurity was associated with a 50% increase in the risk of being diagnosed with ‘high sugar levels’. Finally, women from food insecure households were 30% more likely to be obese compared to their food secure counterparts. These findings suggest that food insecurity may play an important role in preventing adherence with national dietary recommendations, and may increase the risk of obesity and chronic illness. This has important implications for both clinical practice, and the development of interventions and policy to address food insecurity.