807 resultados para Categories of complexes


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Black students are consistently overrepresented in categories of academic underachievement. Parent engagement has long been touted as an effective strategy for improving the educational outcomes of Black children. However, most parent engagement research reflects deficit based perspectives frame Black parents as problems that must be fixed or mitigated before they can positively contribute to their children’s education. Consequently, parent engagement research and frameworks ignore the perspectives of Black parents and the assets they use to participate effectively in parent engagement. In this case study, I draw on individual and focus group interview data, documents, and observations, to examine how fifteen Black families, collectively known as FACE: 1) define and participate in parental engagement, 2) experience barriers to and opportunities for engagement, and 3) experience benefits of engagement for their children and their own personal development. Guided by Black Feminist and Critical Race Theories, I show how Black families in this study used a myriad of engagement strategies to improve their children’s educational experiences which were invisible to schools and how they used school-sanctioned engagement activities to meet their own objectives. Ultimately, I argue that school-centered parent engagement frameworks and models are ineffective for empowering Black families and accounting for the essential ways that these families contribute to the well-being of their children. Based on my findings, I discuss implications for theory, practice and policy, and research, and make recommendations for a more family-centered approach to parent engagement.

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The health of people living with HIV and AIDS (PLWHA) is nutritionally challenged in many nations of the world. The scourge has reduced socio-economic progress globally and more so in sub-Saharan Africa (SSA) where its impact has been compounded by poverty and food insecurity. Good nutrition with proper drug use improves the quality of life for those infected but it is not known how PLWHA exposed to chronic malnutrition and food shortages from developing nations adjust their nutrition with use of Anti-Retro-viral Drugs (ARVs). This study assessed nutritional status, dietary practices, and dietary management of common illnesses that hinder daily food intake by the patients and use of ARVs with food recommendations provided by the health care givers. A descriptive case study design was used to sample 120 HIV-infected patients using systematic sampling procedure. These patients sought health care from an urban slum, Kibera AMREF clinic. Data were collected by anthropometric measurements, bio-chemical analysis, semi-structured questionnaire and secondary data. The Statistical Package for Social Sciences (SPSS) and the Nutri-Survey software packages were used to analyze data. Dietary intakes of micro-nutrients were inadequate for >70% of the patients when compared to the Recommended Daily Requirements. When Body Mass Indices (BMI) were used, only 6.7% of the respondents were underweight (BMI<18.5kg/m2) and 9.2% were overweight (BMI> 25kg/m2), serum albumin test results (mean 3.34±0.06g/dl) showed 60.8% of the respondents were protein deficient and this was confirmed by low dietary protein intakes. The BMI was not related to dietary nutrient intakes, serum albumin and CD4 cell counts (p>0.05). It appeared that there was no significant difference in BMI readings at different categories of CD4 cell count (p>0.05) suggesting that the level of immunity did not affect weight gain with ARV as observed in many studies from developed countries. Malnutrition was, therefore, evident among the 60.8% of the cases as identified by serum albumin tests and food intake was not adequate (68%) for the patients as they ate once a day due to lack of food. National food and nutrition policy should incorporate food security boosting guidelines for the poor people infected with HIV and using ARVs.

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Atomic force microscopy (AFM) allows the analysis of individual polymers at nanostructural level with a minimal sample preparation. This technique has been used to analyse the pectin disassembly process during the ripening and postharvest storage of several fleshy fruits. In general, pectins analysed by AFM are usually visualized as isolated chains, unbranched or with a low number of branchs and, occasionally, as large aggregates. However, the exact nature of these structures is unknown. It has been suggested that pectin aggregates represent a mixture of rhamnonogalacturonan I and homogalacturonan, while isolated chains and their branches are mainly composed by polygalacturonic acid. In order to gain insight into the nature of these structures, sodium carbonate soluble pectins from ripe strawberry (Fragaria x ananassa, Duch.) fruits were subjected to enzymatic digestion with endo-Polygalacturonase M2 from Aspergillus aculeatus, and the samples visualized by AFM at different time intervals. Pectins isolated from control, non-transformed plants, and two transgenic genotypes with low level of expression of ripening-induced pectinase genes encoding a polygalacturonase (APG) or a pectate lyase (APEL) were also included in this study. Before digestion, isolated pectin chains from control were shorter than those from transgenic fruits, showing number-average (LN) contour length values of 73.2 nm vs. 95.9 nm and 91.4 nm in APG and APEL, respectively. The percentage of branched polymers was significantly higher in APG polyuronides than in the remaining genotypes, 33% in APG vs. 6% in control and APEL. As a result of the endo-PG treatment, a gradual decrease in the main backbone length of isolated chains was observed in the three samples. The minimum LN value was reached after 8 h of digestion, being similar in the three genotypes, 22 nm. By contrast, the branches were not visible after 1.5-2 h of digestion. LN values were plotted against digestion time and the data fitted to a first-order exponential decay curve, obtaining R2 values higher than 0.9. The half digestion time calculated with these equations were similar for control and APG pectins, 1.7 h, but significantly higher in APEL, 2.5 h, indicating that these polymer chains were more resistant to endo-PG digestion. Regarding the pectin aggregates, their volumes were estimated and used to calculate LN molecular weights. Before digestion, control and APEL samples showed complexes of similar molecular weights, 1722 kDa, and slightly higher than those observed in APG samples. After endo-PG digestion, size of complexes diminished significantly, reaching similar values in the three pectin samples, around 650 kDa. These results suggest that isolated polymer chains visualized by AFM are formed by a HG domain linked to a shorter polymer resistant to endo-PG digestion, maybe xylogalacturonan or RG-I. The silencing of the pectate lyase gene slightly modified the structure and/or chemical composition of polymer chains making these polyuronides more resistant to enzymatic degradation. Similarly, polygalacturonic acid is one of the main component of the aggregates.

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Although mitigating GHG emissions is necessary to reduce the overall negative climate change impacts on crop yields and agricultural production, certain mitigation measures may generate unintended consequences to food availability and access due to land use competition and economic burden of mitigation. Prior studies have examined the co-impacts on food availability and global producer prices caused by alternative climate policies. More recent studies have looked at the reduction in total caloric intake driven by both changing income and changing food prices under one specific climate policy. However, due to inelastic calorie demand, consumers’ well-being are likely further reduced by increased food expenditures. Built upon existing literature, my dissertation explores how alternative climate policy designs might adversely affect both caloric intake and staple food budget share to 2050, by using the Global Change Assessment Model (GCAM) and a post-estimated metric of food availability and access (FAA). My dissertation first develop a set of new metrics and methods to explore new perspectives of food availability and access under new conditions. The FAA metric consists of two components, the fraction of GDP per capita spent on five categories of staple food and total caloric intake relative to a reference level. By testing the metric against alternate expectations of the future, it shows consistent results with previous studies that economic growth dominates the improvement of FAA. As we increase our ambition to achieve stringent climate targets, two policy conditions tend to have large impacts on FAA driven by competing land use and increasing food prices. Strict conservation policies leave the competition between bioenergy and agriculture production on existing commercial land, while pricing terrestrial carbon encourages large-scale afforestation. To avoid unintended outcomes to food availability and access for the poor, pricing land emissions in frontier forests has the advantage of selecting more productive land for agricultural activities compared to the full conservation approach, but the land carbon price should not be linked to the price of energy system emissions. These results are highly relevant to effective policy-making to reduce land use change emissions, such as the Reduced Emissions from Deforestation and Forest Degradation (REDD).

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O presente trabalho utilizou métodos multivariados e matemáticos para integrar dados químicos e ecotoxicológicos obtidos para o Sistema Estuarino de Santos e para a região próxima à zona de lançamento do emissário submarino de Santos, com a finalidade de estabelecer com maior exatidão os riscos ambientais, e assim identificar áreas prioritárias e orientar programas de controle e políticas públicas. Para ambos os conjuntos de dados, as violações de valores numéricos de qualidade de sedimento tenderam a estar associadas com a ocorrência de toxicidade. Para o estuário, essa tendência foi corroborada pelas correlações entre a toxicidade e as concentrações de HPAs e Cu, enquanto para a região do emissário, pela correlação entre toxicidade e conteúdo de mercúrio no sedimento. Valores normalizados em relação às medias foram calculados para cada amostra, permitindo classificá-las de acordo com a toxicidade e a contaminação. As análises de agrupamento confirmaram os resultados das classificações. Para os dados de sistema estuarino, houve a separação das amostras em três categorias: as estações SSV-2, SSV-3 e SSV-4 encontram-se sob maior risco, seguidas da estação SSV-6. As estações SSV-1 e SSV-5 demonstraram melhores condições. Já em relação ao emissário, as amostras 1 e 2 apresentaram melhores condições, enquanto a estação 5 pareceu apresentar um maior risco, seguida das estações 3 e 4 que tiveram apenas alguns indícios de alteração.

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Paper prepared by Marion Panizzon and Charlotte Sieber-Gasser for the International Conference on the Political Economy of Liberalising Trade in Services, Hebrew University of Jerusalem, 14-15 June 2010 Recent literature has shed light on the economic potential of cross-border networks. These networks, consisting of expatriates and their acquaintances from abroad and at home, provide the basis for the creation of cross-border value added chains and therewith the means for turning brain drain into brain circulation. Both aspects are potentially valuable for economic growth in the developing world. Unilateral co-development policies operating through co-funding of expatriate business ventures, but also bilateral agreements liberalising circular migration for a limited set of per-sons testify to the increasing awareness of governments about the potential, which expatriate networks hold for economic growth in developing countries. Whereas such punctual efforts are valuable, viewed from a long term perspective, these top-down, government mandated Diaspora stimulation programs, will not replace, this paper argues, the market-driven liberalisation of infrastructure and other services in developing countries. Nor will they carry, in the case of circular labour migration, the political momentum to liberalise labour market admission for those non-nationals, who will eventually emerge as the future transnational entrepreneurs. It will take a combination of mode 4 and infrastructure services openings-cum regulation for countries at both sides of the spectrum to provide the basis and precondition for transnational business and entrepreneurial networks to emerge and translate into cross-border, value added production chains. Two key issues are of particular relevance in this context: (i) the services sector, especially in infrastructure, tends to suffer from inefficiencies, particularly in developing countries, and (ii) labour migration, a highly complex issue, still faces disproportionately rigid barriers despite well-documented global welfare gains. Both are hindrances for emerging markets to fully take advantage of the potential of these cross-border networks. Adapting the legal framework for enhancing the regulatory and institutional frameworks for services trade, especially in infrastructure services sectors (ISS) and labour migration could provide the incentives necessary for brain circulation and strengthen cross-border value added chains by lowering transaction costs. This paper analyses the shortfalls of the global legal framework – the shallow status quo of GATS commitments in ISS and mode 4 particular – in relation to stimulating brain circulation and the creation of cross-border value added chains in emerging markets. It highlights the necessity of adapting the legal framework, both on the global and the regional level, to stimulate broader and wider market access in the four key ISS sectors (telecommunications, transport, professional and financial services) in developing countries, as domestic supply capacity, global competitiveness and economic diversification in ISS sectors are necessary for mobilising expatriate re-turns, both physical and virtual. The paper argues that industrialised, labour receiving countries need to offer mode 4 market access to wider categories of persons, especially to students, graduate trainees and young professionals from abroad. Further-more, free trade in semi-finished products and mode 4 market access are crucial for the creation of cross-border value added chains across the developing world. Finally, the paper discusses on the basis of a case study on Jordan why the key features of trade agreements, which promote circular migration and the creation of cross-border value added chains, consist of trade liberalisation in services and liberal migration policies.

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Gender differences in collaborative research have received little at- tention when compared with the growing importance that women hold in academia and research. Unsurprisingly, most of bibliomet- ric databases have a strong lack of directly available information by gender. Although empirical-based network approaches are often used in the study of research collaboration, the studies about the influence of gender dissimilarities on the resulting topological outcomes are still scarce. Here, networks of scientific subjects are used to characterize patterns that might be associated to five categories of authorships which were built based on gender. We find enough evidence that gen- der imbalance in scientific authorships brings a peculiar trait to the networks induced from papers published in Web of Science (WoS) in- dexed journals of Economics over the period 2010-2015 and having at least one author affiliated to a Portuguese institution. Our re- sults show the emergence of a specific pattern when the network of co-occurring subjects is induced from a set of papers exclusively au- thored by men. Such a male-exclusive authorship condition is found to be the solely responsible for the emergence that particular shape in the network structure. This peculiar trait might facilitate future network analyses of research collaboration and interdisciplinarity.

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Background: Among different categories of sedative agents, benzodiazepines have been prescribed for more than three decades to patients of all ages. The effective and predictable sedative and amnestic effects of benzodiazepines support their use in pediatric patients. Midazolam is one of the most extensively used benzodiazepines in this age group. Oral form of drug is the best accepted route of administration in children. Objectives: The purpose of this study was to compare the efficacy and safety of a commercially midazolam syrup versus orally administered IV midazolam in uncooperative dental patients. Second objective was to determine whether differences concerning sedation success can be explained by child‘s behavioral problems and dental fear. Patients and Methods: Eighty eight uncooperative dental patients (Frankl Scales 1,2) aged 3 to 6 years, and ASA I participated in this double blind, parallel randomized, controlled clinical trial. Midazolam was administered in a dose of 0.5 mg/kg for children under the age 5 and 0.2 mg/kg in patients over 5 years of age. Physiologic parameters including heart rate, respiratory rate, oxygen saturation and blood pressure were recorded. Behavior assessment was conducted throughout the course of treatment using Houpt Sedation Rating Scale and at critical moments of treatment (injection and cavity preparation) by North Carolina Scale. Dental fear and behavioral problems were evaluated using Child Fear Schedule Survey-Dental Subscale (CFSS-DS), and Strength and Difficulties Questionnaire (SDQ). Independent t-test, Chi-Square, and Pearson correlation were used for statistical analysis. Results: Acceptable overall sedation ratings were observed in 90% and 86% of syrup and IV/Oral group respectively; Chi-Square P = 0.5. Other domains of Houpt Scale including: sleep, crying and movement were also not significantly different between groups. Physiological parameters remained in normal limits during study without significant difference between groups. Conclusions: “Orally administered IV midazolam” preparation can be used as an alternative for commercially midazolam syrup.

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Online courses have increased in enrollments over the past few decades. As the number of students taking online courses have increased, so has the number of students who have dropped or failed an online course. According to the literature, online courses may have higher drop rates than traditional, face-to-face courses. The number of students who fail an online course is, also, of concern. As online courses may continue to grow over the next few decades, studies on persistence in online courses may benefit students, administrators, instructional designers, educators, and researchers. Although previous research studies have addressed persistence in online courses, very few examine it from the perspectives of students who were unsuccessful in their courses. These students may have unique insights about the online experience that may have related to their lack of success. The purpose of this study was to understand the experiences of university students who have failed or dropped an online course through the lenses of transactional distance theory and Kember’s model of dropout in distance education. Transactional distance theory discusses the dialog, structure, and learner autonomy involved in an online course, while, Kember’s model presents categories that may relate to dropping an online course. Together, the theory and model may help in understanding the experiences of students who have dropped or failed an online course. In this study, semi-structured interviews were conducted with 20 participants from a large Southeastern university in the United States. Based on the participants’ responses, the data was sorted and ranked according to the amount of transactional distance in their courses, as well as the categories of Kember’s model. Many of the participants who experienced low or high transactional distance have, also, expressed an issue with the goal commitment category of Kember’s model. Additionally, there were important differences in the student characteristics of those who dropped or failed an online course. Furthermore, suggestions for improving online courses were given by the participants. Some of these suggestions included more student-instructor interactions, the use of more technology tools in their online course, and for orientations to the online environment to be offered.^

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The focus of this research is to determine if a relationship exists between the stability constant and the initial uptake rate of a mercury species by bacteria. Cultures of the sulfate-reducing bacteria (SRB) strain Desulfovibrio desulfuricans G20 were washed with a bicarbonate buffer solution containing either lactate and sulfate or pyruvate and fumarate. The washed cell solutions were then spiked with either mercury bound to natural organic matter (Hg-NOM) or neutral mercury chloride (HgCl2), followed by sampling over time to provide kinetic data. Despite the significantly different stability constants for Hg-NOM and HgCl2, the calculated initial rate constants for mercury uptake for these two types of complexes appeared to be comparable. Uptake of mercury sulfide species was inconclusive due to possible formation of cinnabar. A simple model that is based on assumptions of passive diffusion and facilitated uptake of mercury by bacteria was evaluated for its potential to simulate the uptake. The model results only agreed with experimental data for HgCl2 uptake.

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The cell phone has become a means of finding persuasive content, making friends and accessing information. For this reason it is of great interest in analyzing is use by young people during their formative years. Regarding this point, the objectives of the research are: to obtain percentage data on the distraction call phones cause among students; to define their habits re fun activities and their study responsibility in their personal and academic lives; and to identify leisure-expressive and referential trends. It was decided to analyze the Spanish discourse found on Twitter. To do so, a quantitative and qualitative methodology was used, with a linguistic pattern extraction tool which allows us to obtain categories of meaning. The sample was 10,000 tweets in Spanish, with key words such as “cell” and “study” and all possible derivatives. The data were gathered between 30 May and the 6 June 2014, which coincides with the start of the exam period in Spain. Finally, the potential applications of the research to the specific field of publicity and advertising is discussed as a possible solution to the current needs of the brands, which have to find participative formats taking into account the students’ leisure trends.

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This article explores Ulrich Beck’s theorisation of risk society through focusing on the way in which the risk of Bt cotton is legitimated by six cultivators in Bantala, a village in Warangal, Andhra Pradesh, in India. The fieldwork for this study was conducted between June 2010 and March 2011, a duration chosen to coincide with a cotton season. The study explores the experience of the cultivators using the ‘categories of legitimation’ defined by Van Leeuwen. These are authorisation, moral evaluation, rationalisation and mythopoesis. As well as permitting an exploration of the legitimation of Bt cotton by cultivators themselves within the high-risk context of the Indian agrarian crisis, the categories also serve as an analytical framework with which to structure a discourse analysis of participant perspectives. The study examines the complex trade-off, which Renn argues the legitimation of ambiguous risk, such as that associated with Bt technology, entails. The research explores the way in which legitimation of the technology is informed by wider normative conceptualisations of development. This highlights that, in a context where indebtedness is strongly linked to farmer suicides, the potential of Bt cotton for poverty alleviation is traded against the uncertainty associated with the technology’s risks, which include its purported links to animal deaths. The study highlights the way in which the wider legitimation of a neoliberal approach to development in Andhra Pradesh serves to reinforce the choice of Bt cotton, and results in a depoliticisation of risk in Bantala. The research indicates, however, that this trade-off is subject to change over time, as economic benefits wane and risks accumulate. It also highlights the need for caution in relation to the proposed extension of Bt technology to food crops, such as Bt brinjal (aubergine).

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This article explores the struggle for legitimation associated with the attempt to define the risk of Bt cotton, a genetically modified crop, in Andhra Pradesh, India. Beck asserts that, given the uncertainty associated with risk society, efforts to define risk are creating the need for a new political culture. This article argues that this political culture emerges from attempts to legitimate power within risk definition. This is examined using critical discourse analysis on interview excerpts with key figures in the Bt cotton debate. Legitimation is explored using the categories of legitimation developed by Van Leeuwen. These are (a) authorisation; (b) moral evaluation; (c) rationalisation; and (d) mythopoesis. The analysis highlights that the political culture which emerges in response to risk society is in a state of constant flux and contingent upon the ongoing struggle for legitimation with regard to the definition of risk.

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Children with chronic conditions often experience a long treatment which can be complex and negatively impacts the child's well-being. In planning treatment and interventions for children with chronic conditions, it is important to measure health-related quality of life (HrQoL). HrQoL instruments are considered to be a patient-reported outcome measure (PROM) and should be used in routine practice. Purpose: The aim of this study was to compare the content dimensions of HrQoL instruments for children's self-reports using the framework of ICF-CY. Method: The sample consist of six instruments for health-related quality of life for children 5 to 18 years of age, which was used in the Swedish national quality registries for children and adolescents with chronic conditions. The following instruments were included: CHQ-CF, DCGM-37, EQ-5D-Y, KIDSCREEN-52, Kid-KINDL and PedsQL 4.0. The framework of the ICF-CY was used as the basis for the comparison. Results: There were 290 meaningful concepts identified and linked to 88 categories in the classification ICF-CY with 29 categories of the component body functions, 48 categories of the component activities and participation and 11 categories of the component environmental factors. No concept were linked to the component body structures. The comparison revealed that the items in the HrQoL instruments corresponded primarily with the domains of activities and less with environmental factors. Conclusions: In conclusion, the results confirm that ICF-CY provide a good framework for content comparisons that evaluate similarities and differences to ICF-CY categories. The results of this study revealed the need for greater consensus of content across different HrQoL instruments. To obtain a detailed description of children's HrQoL, DCGM-37 and KIDSCREEN-52 may be appropriate instruments to use that can increase the understanding of young patients' needs.

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Older people have been identified as being at risk of social exclusion. However, despite the fact that care is commonly required in later life and the majority of that care provided by informal carers, a connection between social exclusion and informal care-receipt has rarely been considered. The aim of this study was to examine how informal care-receipt is related to social exclusion. A face-to-face questionnaire survey on social exclusion and informal care-receipt was carried out among older people (n=1255) living in Barnsley, United Kingdom. Multivariable analyses examined the association between social exclusion and categories of informal care-receipt: care receiver; assurance receiver; non-receiver with no need; non-receiver with need. Compared to being a non-receiver with no need participants were more likely to be a care receiver or assurance receiver if they had higher levels of social exclusion. The highest level of social exclusion, however, was found in non-receivers with need. Despite a lack of informal care and support, formal practical support and personal care was also low in this latter group. Findings are discussed in relation to the conceptualisation of care-receipt and how contact with medical services could be an opportunity for identification and appropriate referral of non-receivers with need.