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PURPOSE: To verify the association between family resources, sociodemographic aspects, and school performance in middle school students. METHODS: Observational, analytical, cross-sectional study with a probabilistic sample stratified by sex, age, and grade in school. A total of 124 adolescents of both sexes, aged 11 to 14 years, enrolled in a private middle school participated in the study. We sent to their parents/guardians an online form with the Home Environment Resources Scale (HER), Brazilian Economic Classification Criteria (CCEB), and sociodemographic questions. The school performance was furnished by the institution. We used frequency distribution analysis of categorical variables and measures of central tendency and dispersion of the continuous ones. We used the Mann-Whitney, Kruskal-Wallis, and Spearman correlation coefficient tests and set the significance level at p ≤ 0.05. RESULTS: Most of the sample was 11 years old, females, sixth graders, with very good school performance, belonging to social class A, and whose householder had a bachelor's degree. Age and grade in school were associated with interaction with the parents, "family-school connection", and total HER score. The "proximal processes" had a moderate positive correlation with outings and toys. There was a moderate positive correlation between total HER score and "predictable activities that indicate stability". The "proximal processes" had a strong positive correlation with "family-school connection". There was a weak positive correlation between books available at home and school performance. CONCLUSION: The family resources were related to the adolescents' school performance.

OBJETIVO: Verificar a associação entre recursos do ambiente familiar, aspectos sociodemográficos e desempenho escolar de estudantes do Ensino Fundamental. MÉTODO: Estudo observacional analítico transversal, com amostra probabilística estratificada por sexo, idade e ano escolar. Participaram 124 adolescentes, de ambos os sexos, entre 11 e 14 anos, matriculados no Ensino Fundamental II de uma instituição particular. Os responsáveis receberam um formulário online contendo: Inventário dos Recursos do Ambiente Familiar (RAF), Critério de Classificação Econômica Brasil (CCEB) e questões sociodemográficas. O desempenho escolar foi fornecido pela instituição. Realizou-se distribuição de frequência das variáveis categóricas e medidas de tendência central e de dispersão para as contínuas. Utilizou-se os testes Mann-Whitney, Kruskal-Wallis e coeficiente de correlação de Spearman, sendo considerados significantes os que apresentaram valor de p≤0,05. RESULTADOS: A maioria da amostra possuía 11 anos, do sexo feminino, cursava o 6º ano do Ensino Fundamental, obteve desempenho escolar muito bom, apresentava classificação A e declarou que a/o chefe de família possuía Ensino Superior completo. Houve associação entre idade e ano escolar com a interação com os pais, ligação família-escola e RAF total. Os processos proximais demonstraram correlação positiva de magnitude moderada com passeios e brinquedos. Houve correlação positiva moderada entre total do RAF e atividades previsíveis que sinalizam estabilidade. Os processos proximais se correlacionaram de maneira positiva forte com a ligação família-escola. Ter livros em casa revelou correlação positiva fraca com o desempenho escolar. CONCLUSÃO: Os recursos do ambiente familiar apresentaram relação com o desempenho escolar dos adolescentes.

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Resumo Objetivo Verificar a associação entre recursos do ambiente familiar, aspectos sociodemográficos e desempenho escolar de estudantes do Ensino Fundamental. Método Estudo observacional analítico transversal, com amostra probabilística estratificada por sexo, idade e ano escolar. Participaram 124 adolescentes, de ambos os sexos, entre 11 e 14 anos, matriculados no Ensino Fundamental II de uma instituição particular. Os responsáveis receberam um formulário online contendo: Inventário dos Recursos do Ambiente Familiar (RAF), Critério de Classificação Econômica Brasil (CCEB) e questões sociodemográficas. O desempenho escolar foi fornecido pela instituição. Realizou-se distribuição de frequência das variáveis categóricas e medidas de tendência central e de dispersão para as contínuas. Utilizou-se os testes Mann-Whitney, Kruskal-Wallis e coeficiente de correlação de Spearman, sendo considerados significantes os que apresentaram valor de p≤0,05. Resultados A maioria da amostra possuía 11 anos, do sexo feminino, cursava o 6º ano do Ensino Fundamental, obteve desempenho escolar muito bom, apresentava classificação A e declarou que a/o chefe de família possuía Ensino Superior completo. Houve associação entre idade e ano escolar com a interação com os pais, ligação família-escola e RAF total. Os processos proximais demonstraram correlação positiva de magnitude moderada com passeios e brinquedos. Houve correlação positiva moderada entre total do RAF e atividades previsíveis que sinalizam estabilidade. Os processos proximais se correlacionaram de maneira positiva forte com a ligação família-escola. Ter livros em casa revelou correlação positiva fraca com o desempenho escolar. Conclusão Os recursos do ambiente familiar apresentaram relação com o desempenho escolar dos adolescentes.

ABSTRACT Purpose To verify the association between family resources, sociodemographic aspects, and school performance in middle school students. Methods Observational, analytical, cross-sectional study with a probabilistic sample stratified by sex, age, and grade in school. A total of 124 adolescents of both sexes, aged 11 to 14 years, enrolled in a private middle school participated in the study. We sent to their parents/guardians an online form with the Home Environment Resources Scale (HER), Brazilian Economic Classification Criteria (CCEB), and sociodemographic questions. The school performance was furnished by the institution. We used frequency distribution analysis of categorical variables and measures of central tendency and dispersion of the continuous ones. We used the Mann-Whitney, Kruskal-Wallis, and Spearman correlation coefficient tests and set the significance level at p ≤ 0.05. Results Most of the sample was 11 years old, females, sixth graders, with very good school performance, belonging to social class A, and whose householder had a bachelor's degree. Age and grade in school were associated with interaction with the parents, "family-school connection", and total HER score. The "proximal processes" had a moderate positive correlation with outings and toys. There was a moderate positive correlation between total HER score and "predictable activities that indicate stability". The "proximal processes" had a strong positive correlation with "family-school connection". There was a weak positive correlation between books available at home and school performance. Conclusion The family resources were related to the adolescents' school performance.

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The aim of this study was to evaluate the effect of supplementing serum-containing media with a mixture of cis- and trans-9,11- and -10,12-conjugated isomers of linoleic acid (CLA) during different steps of the in vitro production (IVM, IVC, or IVM + IVC) of bovine embryos on their embryonic development, cryotolerance, and lipid profile. To evaluate the impact of the CLA on membrane lipids, such as phosphatidylcholine (PC) and sphingomyelin (SM), the embryos' lipid profiles were obtained using matrix-assisted laser desorption ionization mass spectrometry. The cleavage rates (78.6%-84.8%) and blastocyst development (44.8%-51.2%) remained unaltered. The postthawing reexpansion rates were higher (P < 0.05) when the CLA was added to the IVM medium (82.6%) or to the IVM + IVC medium (83.8%) than the control (69.3%) or IVC medium (63.0%). Changes in the blastocysts' lipid profile occurred when supplementation was restricted to the IVM or IVC medium. However, the most prominent effects of the CLA on the embryonic PC and SM profiles were observed when the supplement was added to IVM + IVC media, which was an increase in the level of highly unsaturated PCs containing 36 or 38 carbons, which are likely to contain CLA residues. These results showed that the molecular mechanism resulting in the improved cryosurvival, observed with CLA supplementation during bovine embryonic in vitro production, was related to the composition of structural lipids of cellular membranes and is dependent on the treatment length. Monitoring the lipid profile of embryonic membranes may improve the CLA supplementation strategy and facilitate the development of new IVC systems to improve the cryopreservation of bovine embryos and those of other domestic species.

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The use of low quality seeds with a lower physiological reflects one of the major causes of low productivity. Thus the storage conditions of seed must be taken into consideration. This research aimed to evaluate the influence of natural and synthetic insecticides on emergence and seed storage of crambe, as these substances are essential to prevent infestation of seeds of other species by harmful organisms. The experimental design was a randomized block in factorial 3 x 8 ( 8 substances and 3 storage times ) with 4 replications. We assessed the following natural insecticides: saffron, lime, ash, neem, diatomaceous earth, and synthetic: chlorpyrifos and deltamethrin; besides the control consisting of seeds without any treatment. We evaluated the percentage of emergence, speed of emergence index and time to reach 50 % of emergency. In all characteristics, it was found that no influence of neem on seed vigor. There are disadvantages in the application of the insecticides chlorpyrifos and diatomaceous earth, which interfered with the emergence rate of seeds of crambe. The seeds treated with other insecticides had different behavior of untreated seeds after 120 days of storage to assess the time that they take to reach 50 % germination.(AU)

O uso de sementes de baixa qualidade, com um menor potencial fisiológico, reflete numa das principais causas da baixa produtividade. Sendo assim as condições de armazenamento de sementes devem ser levadas em consideração. Esta pesquisa teve por objetivo avaliar a influência de inseticidas naturais e sintéticos na emergência e no armazenamento de sementes de crambe, já que tais sustâncias são indispensáveis para evitar a infestação das sementes de outras espécies por organismos nocivos. O delineamento experimental foi em blocos ao acaso, no esquema fatorial 8 x 3 (8 substâncias e 3 tempos de armazenamento), com 4 repetições. Avaliaram-se os seguintes inseticidas naturais: açafrão, calcário, cinza, nim, terra de diatomáceas; e sintéticos: clorpirifós e deltametrina; além do tratamento controle, constituído de sementes sem qualquer tipo de tratamento. Avaliaram-se a porcentagem de emergência, o índice de velocidade de emergência e tempo para atingir 50% da emergência. Em todas as características avaliadas, constatou-se nenhuma influência do nim sobre o vigor das sementes. Verificou-se desvantagens na aplicação dos inseticidas clorpirifós e terra de diatomáceas, que interferiram na velocidade de emergência das sementes de crambe. As sementes tratadas com os demais inseticidas tiveram comportamento diferenciado das sementes não tratadas após os 120 dias de armazenamento ao avaliar o tempo que as mesmas demoram a atingir 50% de emergência.(AU)

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The use of low quality seeds with a lower physiological reflects one of the major causes of low productivity. Thus the storage conditions of seed must be taken into consideration. This research aimed to evaluate the influence of natural and synthetic insecticides on emergence and seed storage of crambe, as these substances are essential to prevent infestation of seeds of other species by harmful organisms. The experimental design was a randomized block in factorial 3 x 8 ( 8 substances and 3 storage times ) with 4 replications. We assessed the following natural insecticides: saffron, lime, ash, neem, diatomaceous earth, and synthetic: chlorpyrifos and deltamethrin; besides the control consisting of seeds without any treatment. We evaluated the percentage of emergence, speed of emergence index and time to reach 50 % of emergency. In all characteristics, it was found that no influence of neem on seed vigor. There are disadvantages in the application of the insecticides chlorpyrifos and diatomaceous earth, which interfered with the emergence rate of seeds of crambe. The seeds treated with other insecticides had different behavior of untreated seeds after 120 days of storage to assess the time that they take to reach 50 % germination.

O uso de sementes de baixa qualidade, com um menor potencial fisiológico, reflete numa das principais causas da baixa produtividade. Sendo assim as condições de armazenamento de sementes devem ser levadas em consideração. Esta pesquisa teve por objetivo avaliar a influência de inseticidas naturais e sintéticos na emergência e no armazenamento de sementes de crambe, já que tais sustâncias são indispensáveis para evitar a infestação das sementes de outras espécies por organismos nocivos. O delineamento experimental foi em blocos ao acaso, no esquema fatorial 8 x 3 (8 substâncias e 3 tempos de armazenamento), com 4 repetições. Avaliaram-se os seguintes inseticidas naturais: açafrão, calcário, cinza, nim, terra de diatomáceas; e sintéticos: clorpirifós e deltametrina; além do tratamento controle, constituído de sementes sem qualquer tipo de tratamento. Avaliaram-se a porcentagem de emergência, o índice de velocidade de emergência e tempo para atingir 50% da emergência. Em todas as características avaliadas, constatou-se nenhuma influência do nim sobre o vigor das sementes. Verificou-se desvantagens na aplicação dos inseticidas clorpirifós e terra de diatomáceas, que interferiram na velocidade de emergência das sementes de crambe. As sementes tratadas com os demais inseticidas tiveram comportamento diferenciado das sementes não tratadas após os 120 dias de armazenamento ao avaliar o tempo que as mesmas demoram a atingir 50% de emergência.

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Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

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Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative ß-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

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INTRODUCTION: The oil obtained from Pterodon pubescens (Leguminosae) seeds are known to display anti-cancer, anti-dermatogenic and anti-nociceptive activitiy. Phytochemical studies have demonstrated that its main constituents are diterpenoids with voucapan skeletons. Considering the potential biological activities of the oil, rapid and efficient methods for assessing its quality would facilitate certification and quality control. OBJECTIVE: To develop a direct mass spectrometric fingerprinting method for the P. pubescens seed oil that would focus on the major diterpenoids constituents, enabling quality control, origin certification and recognition of marker species in commercially available products. METHOD: Two techniques were used: (i) direct infusion electrospray ionisation (ESI) mass spectrometry after solvent extraction and dilution and (ii) ambient desorption/ionisation via easy ambient sonic-spray ionisation, EASI(+)-MS, performed directly on the seed surface or at a paper surface imprinted with the oil. RESULTS: From a combination of ESI-MS, HRESI-MS and ESI-MS/MS data, 12 diterpenes were characterised, and typical profiles were obtained for the oil extract or the crude oil via both ESI-MS and EASI-MS. These techniques require no or very simple sample preparation protocols and the whole analytical processes with spectra acquisition take just a few minutes. CONCLUSION: Both techniques, but particularly EASI-MS, provide simple, fast and efficient MS fingerprinting methodologies to characterise the P. pubescens oil with typical (di)terpene profiles being applicable to quality control and certification of authenticity and origin.

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Knowing the importance of preventive use of insecticides for seed treatment, this study aimed to identify potential insect pests of storage for seeds of radish by means of traps set on the field for six months and to evaluate the effect of natural and synthetic substances insecticides on the emergence of radish seedlings stored for 120 days. The bioassay, field-level, was conducted over a period of six months in the following environments: savannah, area of cultivation of crops, pasture and forest at the Federal Institute Goiano. For each of these environments were placed five traps made of PET bottles, containing respectively in maize, millet, soybean, crambe and wild radish. The traps were inspected every seven days to verify the the occurrence of insects plague. The substances were: 1) saffron, 2) limestone, 3) Gray, 4) neem, 5) diatomaceous earth, 6) chlorpyrifos, 7) deltamethrin and 8) control treatment. The experimental design was randomized blocks in factorial scheme 8 x 2 (8 substances and two storage periods, is not stored seeds and seeds stored for 120 days) with four replications. Were evaluated the percentage of emergence, hold rate of emergence, time to reach 50% emergence and the record of the dry mass of seedlings. The natural and synthetic substances do not interfere with seedling emergence in seeds of wild radish, even after storage for 120 days in a room. In t

Sabendo da importância do uso preventivo de inseticidas no tratamento de sementes, esta pesquisa teve por objetivos identificar possíveis insetos praga de armazenamento para sementes de nabo forrageiro por meio de armadilhas montadas em campo durante seis meses e avaliar o efeito de substâncias inseticidas, naturais e sintéticas na emergência de plântulas em sementes de nabo forrageiro armazenadas por 120 dias. O bioensaio, em nível de campo, foi conduzido por um período de seis meses nos seguintes ambientes: cerrado, área de cultivo de grandes culturas, pastagem e mata do Instituto Federal Goiano. Para cada um desses ambientes foram colocadas cinco armadilhas confeccionadas em garrafas PET, contendo respectivamente sementes de milho, milheto, soja, crambe e nabo forrageiro. As armadilhas foram inspecionadas a cada sete dias para a verificação da ocorrência de insetos praga. As substâncias consistiram de: 1) açafrão, 2) calcário, 3) cinza, 4) nim, 5) terra de diatomáceas, 6) clorpirifós, 7) deltametrina e 8) tratamento controle. O delineamento experimental foi em blocos ao acaso, no esquema fatorial 8 x 2, sendo oito substâncias e armazenamento por zero e 120 dias, com 4 repetições. Avaliaram-se porcentagem de emergência, índice de velocidade de emergência, tempo para atingir 50% da emergência e massa seca das plântulas emergidas. As substâncias naturais e sintéticas não interf

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Knowing the importance of preventive use of insecticides for seed treatment, this study aimed to identify potential insect pests of storage for seeds of radish by means of traps set on the field for six months and to evaluate the effect of natural and synthetic substances insecticides on the emergence of radish seedlings stored for 120 days. The bioassay, field-level, was conducted over a period of six months in the following environments: savannah, area of cultivation of crops, pasture and forest at the Federal Institute Goiano. For each of these environments were placed five traps made of PET bottles, containing respectively in maize, millet, soybean, crambe and wild radish. The traps were inspected every seven days to verify the the occurrence of insects plague. The substances were: 1) saffron, 2) limestone, 3) Gray, 4) neem, 5) diatomaceous earth, 6) chlorpyrifos, 7) deltamethrin and 8) control treatment. The experimental design was randomized blocks in factorial scheme 8 x 2 (8 substances and two storage periods, is not stored seeds and seeds stored for 120 days) with four replications. Were evaluated the percentage of emergence, hold rate of emergence, time to reach 50% emergence and the record of the dry mass of seedlings. The natural and synthetic substances do not interfere with seedling emergence in seeds of wild radish, even after storage for 120 days in a room. In t

Sabendo da importância do uso preventivo de inseticidas no tratamento de sementes, esta pesquisa teve por objetivos identificar possíveis insetos praga de armazenamento para sementes de nabo forrageiro por meio de armadilhas montadas em campo durante seis meses e avaliar o efeito de substâncias inseticidas, naturais e sintéticas na emergência de plântulas em sementes de nabo forrageiro armazenadas por 120 dias. O bioensaio, em nível de campo, foi conduzido por um período de seis meses nos seguintes ambientes: cerrado, área de cultivo de grandes culturas, pastagem e mata do Instituto Federal Goiano. Para cada um desses ambientes foram colocadas cinco armadilhas confeccionadas em garrafas PET, contendo respectivamente sementes de milho, milheto, soja, crambe e nabo forrageiro. As armadilhas foram inspecionadas a cada sete dias para a verificação da ocorrência de insetos praga. As substâncias consistiram de: 1) açafrão, 2) calcário, 3) cinza, 4) nim, 5) terra de diatomáceas, 6) clorpirifós, 7) deltametrina e 8) tratamento controle. O delineamento experimental foi em blocos ao acaso, no esquema fatorial 8 x 2, sendo oito substâncias e armazenamento por zero e 120 dias, com 4 repetições. Avaliaram-se porcentagem de emergência, índice de velocidade de emergência, tempo para atingir 50% da emergência e massa seca das plântulas emergidas. As substâncias naturais e sintéticas não interf

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A presente dissertação aborda a questão da juventude na atualidade e o que seconvencionou chamar de masculinidades. Compreende-se as masculinidades não como algofixo, ou processo, mas como algo fluído, objeto de estudo de nosso tempo, e por isso, transformado em conceito. A fim de compreender essa problemática, esta pesquisa visa investigar os diferentes modos e concepções dos jovens, hoje, em relação ao ser jovem, àsexualidade, às questões de gênero, de corpo, e à saúde. Para tanto, realizou-se uma pesquisa de campo, de caráter etnográfico, e uma pesquisa de cunho bibliográfico. Procedemos,primeiramente, uma investigação teórica acerca das possíveis imbricações entre juventude, masculinidades e saúde, percorrendo tanto autores que problematizaram o conceito de juventude, como os estudos de sexualidade, de inspiração foucaultiana e ainda novas pesquisas no campo damasculinidade e da saúde. Em seguida, descrevemos e analisamos nossa pesquisa de campo, realizada em uma escola de ensino médio, e dividida em dois momentos: um primeiro em queforam realizadas 30 entrevistas individuais com jovens de 14 a 21 anos, e um segundo em foram discutidas cenas pré-selecionadas de filmes sobre o tema da pesquisa, em dois pequenos grupos. Para finalizar, fizemos uma síntese entre os autores investigados e o material etnográfico, na tentativa de refletir sobre as possibilidades presentes para os jovens no contexto contemporâneo, e as do grupo estudado. A pesquisa se propõe como meio através do qual pretendemos pensar e destacar, no contemporâneo, os movimentos e as inércias presentes na juventude, no que tange à sexualidade e às masculinidades, e como estes se relacionam com a saúde e com o projetobiopolítico.

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OBJECTIVE: The aim of this study was to examine and describe our experience with the use of peripheral parenteral nutrition (PPN). METHODS: Patients with an indication for parenteral nutrition for less than 15 days received it via a peripheral vein via a short, 20 or 22 gauge French polyurethane catheter. Parenteral nutrition had a final osmolality of 993 mOsm/l and was administered by infusion pump. The nutritional status of patients was assessed by the Subjective Global Assessment (SGA) technique. Patients were followed by a trained nutritional team and the access site was changed if problems developed. RESULTS: Fifty-three patients were followed with a mean age of 59.5 +/- 17.5 years. There were 36 males (69.2%). Nutritional requirements were reached in 67.6% of the patients within 2.9 +/- 0.7 days. The mean time on parenteral nutrition was 7.2 +/- 6.6 days. In 74.3% of the cases parenteral nutrition was offered until the end of the planned treatment. Pain at the venipuncture site occurred in 17.1% of the cases, pain and fever in 20% and pain, hyperthermia and edema in 2.8%. No patient developed an abscess. CONCLUSIONS: PPN can benefit a great number of patients without the risks linked to a venous central catheter. Complications associated with PPN are low especially when the care and follow-up are provided by a nutritional support team.

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Affinity diacetylene liposomes were prepared with 10,12-tricosadiynoic acid and cardiolipin as the affinity ligand for anticardiolipin antibodies at a molar ratio of 80:20. Polymerization was carried out under UV irradiation, and the color transitions were monitored by visible absorption spectroscopy. Peaks at 635 nm (blue form), 540 nm (purple form), and 480 nm (red form) were observed as a function of time. These polymerized liposomes were used in a noncompetitive immunoassay for detection of anticardiolipin antibodies. Color changes were observed when reference serum containing specific immunoglobulin G, IgG, was added to polymerized liposome dispersions. The colorimetric signal due to IgG adsorption on the liposome surface was quantified as a colorimetric response defined as the change in percentage of blue color related to the initial percentage of blue color in the solutions. The colorimetric response was 10 times higher for specific IgG compared with nonspecific ones. These results suggest the unique potentialities of affinity diacetylene polymerized liposomes in the development of biosensors for diagnosis of autoimmune diseases.

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This article uses the Adaptive Gaussian Representation (AGR) for human electroencephalogram (EEG) feature extraction aiming the discrimination among mental tasks to be used in a brain computer interface (BCI). It does not focus on the AGR time-frequency representation, but rather on their projection coefficients. Ten volunteers were asked to imagine either right or left hand movement, according to a proper visual stimulus. The features of the resulting EEG signals were characterised by extracting AGR coefficients. Classification was carried out using a Multilayer perceptron (MLP) trained with the classical backpropagation algorithm. Overall results show that AGR coefficients representation is able to reveal a significant EEG discrimination between imagination of right and left hand movement with a mean classification performance of 91%+/-5.8% achieved for female subjects and 87%+/-5.0% achieved for male subjects.

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A novel approach to artificial neural networks is presented. The philosophy of this approach is based on two aspects: the design of task-specific networks, and a new neuron model with multiple synapses. The synapses' connective strengths are modified through selective and cumulative processes conducted by axo-axonic connections from a feedforward circuit. This new concept was applied to the position control of a planar two-link manipulator exhibiting excellent results on learning capability and generalization when compared with a conventional feedforward network. In the present paper, the example shows only a network developed from a neuronal reflexive circuit with some useful artifices, nevertheless without the intention of covering all possibilities devised.

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PIP: An overview was provided of some of the economic and social changes in Mexico that impact on women. At the Colegio de Postgraduados, an ongoing project will examine women's work roles in an agricultural setting. The Ford Foundation has funded research studies at Mexican universities. One such study will examine women workers in foreign-owned factories producing duty free export goods; another study involves interviews with street vendors in the informal sector. Jose Alonso is a specialist on the Mexican garment industry, teaches at the University of the Americas, and advises at the Autonomous Technological Institute of Mexico. He contends that the process of development can best be understood by examining the informal sector. There is no Mexican tradition of a business class. Scholars at the Colegio de Postgraduados' Center for Rural Development are exploring income generation schemes, and building a master's degree program specializing in gender and rural development. The program would train professionals with an understanding of the needs of rural women and appropriate strategies for improving women's social and economic conditions. Crises have precipitated major shifts in work patterns in Mexico. During the 1980s, inflation and unemployment rapidly increased and income declined to 1970s levels. Mass movement of women into the labor force occurred. For many women, the dual role in long paid work hours and family and domestic care has produced independence with a big price tag. Manufacturing jobs along the free trade border areas have provided work opportunities for women, who hold 70% of the jobs. These jobs have moved from low paid menial tasks to higher skilled and better paid positions with training, but only for some women. There are few unions, and the government Confederation of Mexican Workers does not include women. Notwithstanding working conditions, women confront other problems with housing and the lack of basic amenities such as electricity, tap water, trash collection, and paved roads and walkways. Border areas such as Juarez attract 200 unemployed daily. Unregulated growth will turn these border cities into densely populated areas. About 40% of the economically active population work in the informal sector. Much of the vendor merchandise is illegal contraband, and intricate handicrafts are sold next to electronic games, cosmetics, and silk-screened T shirts. Informal work is also available for women in cottage industries at home. The Agro-Industrial Women's Unit in Buenavista helps to secure agricultural land holdings for women.^ieng

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