950 resultados para Univalent Functions with Negative Coefficients


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This study examined the psychometric properties of the Brazilian versions of the Fagerstrom Test for Nicotine Dependence (FTND) and the Heaviness of Smoking Index (HSI). The test-retest reliability of the FTND was assessed in a sample of 61 smoking university students, with a 15-day interval between assessments. The interrater reliability was examined in 30 smoking patients of a psychosocial care center for alcohol and drug users (PCC-AD). The reliability coefficient was estimated by the kappa and intraclass correlation coefficients. The predictive validity, internal consistency, and factor structure of the FTND and the HSI were evaluated by factor analysis in 271 smokers treated at an emergency unit and at the PCC-AD. The gold standard was the nicotine dependence criteria of DSM-IV, as assessed by the Structured Clinical Interview for DSM-IV. The FTND showed high reliability, with correlation coefficients of .92 for test-retest reliability and .99 for interrater reliability. Both the FTND and the HSI presented high levels of sensitivity and specificity. The internal consistency evaluation yielded a Cronbach`s alpha coefficient of .83 for the FTND and of .56 for the HSI. An exploratory factor analysis found 2 factors in the FTND, which were validated by a confirmatory factor analysis. The results obtained in this study confirm the validity and reliability of the Brazilian versions of the FTND and the HSI.

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The in vitro schistosomicidal activity of curcumin (doses ranging from 5 to 100 mu M) was carried out against Schistosoma mansoni adult worms. Curcumin (at 50 and 100 mu M) caused death of all worms. When tested at the doses of 5 and 20 mu M, it decreased the worm viability in comparison with negative (Roswell Memorial Park Institute (RPMI) 1640 medium alone or RPMI 1640 medium with 10% dimethyl sulfoxide) and positive (heat-killed worms at 56A degrees C or praziquantel 10 mu M) control groups. All pairs of coupled adult worms were separated into individual male and female by the action of curcumin at the doses of 20 to 100 mu M. When tested at 5 and 10 mu M, curcumin reduced egg production by 50% in comparison with the positive control group. It is the first time that the schistosomicidal activity has been reported for curcumin.

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The objectives of this study were (1) to determine the sensitivity (Se) and specificity (Sp) of somatic cell count (SCC) thresholds to identify subclinical mastitis in Gyr cows caused by major and minor pathogens; (2) to study the effects of month of sampling, rear or front mammary quarters, herd, intramammary infection (IMI), and bacterial species on SCC at quarter level; and (3) to describe the prevalence of IMI in Gyr cows in commercial dairy herds. In total, 221 lactating Gyr cows from 3 commercial dairy farms were selected. Milk samples were collected from individual quarters once a month for 1 yr from all lactating cows for SCC and bacteriological analysis. Mammary quarters were considered the experimental units and the SCC results were log(10)-transformed. Four SCC thresholds (100, 200, 300 and 400 x 10(3) cells/mL) were used to determine Se and Sp to identify infected mammary quarters. The overall prevalence of IMI in quarter milk samples of Gyr cows was 49.8%, and the prevalence of minor pathogens was higher (31.9%) than that of major pathogens (17.8%). Quarter samples with microbial isolation presented higher SCC compared with negative samples. Sensitivity and Sp of selected SCC thresholds varied according to the group of pathogen (major and minor) involved in the IMI definition. Sensitivity increased and Sp decreased when mammary quarters with only major pathogens isolation were considered positive. The use of a single SCC analysis to classify quarters as uninfected or infected in Gyr cows may not be a useful test for this breed because Se and Sp of SCC at the studied thresholds were low. The occurrence of IMI and the bacterial species are the main factors responsible for SCC variation in mammary quarters of Gyr cows. Milk samples with major pathogens isolation elicited higher SCC than those with minor pathogens.

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The prognostic significance of positive peritoneal cytology in endometrial carcinoma has led to the incorporation of peritoneal cytology into the current FIGO staging system, While cytology was shown to be prognostically relevant in patients with stage II and III disease, conflicting data exists about its significance in patients who would have been stage I but were classified as stage III solely and exclusively on the basis of positive peritoneal cytology (clinical stage I). Analysis was based on the data of 369 consecutive patients with clinical stage I endometrioid adenocarcinoma of the endometrium. Standard treatment consisted of an abdominal total hysterectomy, bilateral salpingo-oophorectomy with or without pelvic lymph node dissection. Peritoneal cytology was obtained at laparotomy by peritoneal washing of the pouch of Douglas and was considered positive if malignant cells could be detected regardless of the number of malignant cells present. Disease-free survival (DFS) was considered the primary statistical endpoint. In 13/369 (3.5%) patients, positive peritoneal cytology was found. The median follow-up was 29 months and 15 recurrences occurred. Peritoneal cytology was independent of the depth of myometrial invasion and the grade of tumour differentiation, Patients with negative washings had a DFS of 96'7e at 36 months compared with 67% for patients with positive washings (log-rank P < 0.001). The presence of positive peritoneal cytology in patients with clinically stage I endometrioid adenocarcinoma of the endometrium is considered an adverse prognostic factor. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

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Based on the idea that emotional exchanges determine symbolic meanings in interpersonal exchanges, we hypothesized that displays of positive and congruent affect determine members' ratings of leaders in a simulated performance appraisal context. To test the hypotheses, 537 participants viewed videotapes of four male and female leaders giving positive and negative feedback, and with facial expressions of affect that were either congruent or incongruent with the verbal message that they were delivering. Results supported hypotheses that positive and message-congruent leader affect results in more positive member ratings of the leader, assessed using a seven-item measure of members' perceptions of the leader's negotiating latitude. The least positive ratings of negotiating latitude were given when positive feedback was delivered with negative facial affect. (C) 2002 Elsevier Science Inc. All rights reserved.

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The extent to which density-dependent processes regulate natural populations is the subject of an ongoing debate. We contribute evidence to this debate showing that density-dependent processes influence the population dynamics of the ectoparasite Aponomma hydrosauri (Acari: Ixodidae), a tick species that infests reptiles in Australia. The first piece of evidence comes from an unusually long-term dataset on the distribution of ticks among individual hosts. If density-dependent processes are influencing either host mortality or vital rates of the parasite population, and those distributions can be approximated with negative binomial distributions, then general host-parasite models predict that the aggregation coefficient of the parasite distribution will increase with the average intensity of infections. We fit negative binomial distributions to the frequency distributions of ticks on hosts, and find that the estimated aggregation coefficient k increases with increasing average tick density. This pattern indirectly implies that one or more vital rates of the tick population must be changing with increasing tick density, because mortality rates of the tick's main host, the sleepy lizard, Tiliqua rugosa, are unaffected by changes in tick burdens. Our second piece of evidence is a re-analysis of experimental data on the attachment success of individual ticks to lizard hosts using generalized linear modelling. The probability of successful engorgement decreases with increasing numbers of ticks attached to a host. This is direct evidence of a density-dependent process that could lead to an increase in the aggregation coefficient of tick distributions described earlier. The population-scale increase in the aggregation coefficient is indirect evidence of a density-dependent process or processes sufficiently strong to produce a population-wide pattern, and thus also likely to influence population regulation. The direct observation of a density-dependent process is evidence of at least part of the responsible mechanism.

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Background: The surgical cure rate for primary hyperparathyroidism is greater than 95%. For those who have recurrent or persistent disease, preoperative localization improves reoperation success rates. Selective parathyroid venous sampling (SPVS) for intact parathyroid hormone is particularly useful when non-invasive localization techniques are negative or inconclusive. Methods: We present all known cases (n = 13) between 1994 and 2002 who had venous sampling for localization at our institution prior to reoperation for recurrent or persistent primary hyperparathyroidism. Comparison was made with non-invasive localization procedures. Results of invasive and non-invasive localization were correlated with surgical findings. Results: Of the nine reoperated cases, eight had positive correlations between SPVS and operative findings and histopathology. SPVS did not reveal the parathyroid hormone source in one case with negative non-invasive localization procedures. Comparisons between SPVS, computerized tomography (CT), and parathyroid scintigraphy (MIBI) as expressed in terms of true positive (TP), false positive (FP) and false negative (FN) were: SPVS - TP 88.8%, FP 0%, FN 11.1%; CT - TP 22.2%, FP 22.2%, FN 55.5%; and MIBI - TP 33.3%, FP 0%, FN 66.6%. At least seven of the nine operated cases have been cured; another remained normocalcaemic 2 weeks after subtotal parathyroidectomy. Conclusion: In our institution SPVS has proven to be a valuable tool in cases with recurrent or persistent primary hyperparathyroidism and negative non-invasive localization procedures.

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O presente trabalho objetiva avaliar a qualidade dos serviços prestados pela Biblioteca Central (BC) da Universidade Federal do Espírito Santo (UFES) utilizando o método Servqual. Esta pesquisa é um estudo de caso de natureza quantitativa e qualitativa. A triangulação dos dados foi realizada por meio de uma survey com 363 usuários, entrevista com nove servidores que atuam na Biblioteca e consulta a documentos da universidade que descrevem as características básicas da Biblioteca Central. A survey foi aplicada utilizando-se questionário desenvolvido com base na escala Servqual em pré-teste realizado na Biblioteca Setorial Tecnológica (BST) da UFES. Foram utilizadas duas modalidades de coleta na survey aplicada na BC: presencial e online. Foram coletados 110 questionários presenciais e 253 online. As entrevistas com os servidores da BC foram baseadas nos 116 registros de reivindicações dos usuários, coletados pela BC anteriormente à pesquisa. Além desses documentos, consultaramse informações institucionais divulgadas no catálogo de serviços da BC e em páginas da BC e da UFES na internet. Identificaram-se quatro dimensões da qualidade dos serviços prestados pela BC, com médias negativas, indicando necessidade de melhoria nos serviços prestados. As ações prioritárias recomendadas para a BC são: a) melhorar instalações físicas e equipamentos; e b) capacitar e motivar os trabalhadores para atendimento aos usuários. Essas ações devem conduzir a soluções de problemas relacionados a condições de estudo (iluminação, climatização, água, banheiros, espaço físico, móveis e silêncio) e acesso a informação (internet, autoempréstimo, quantitativo de exemplares, limitação do empréstimo e alerta quanto à data de renovação).

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O cultivo do café é uma das atividades do agronegócio de maior importância socioeconômica dentre as diferentes atividades ligadas ao comércio agrícola mundial. Uma das maiores contribuições da genética quantitativa para o melhoramento genético é a possibilidade de prever ganhos genéticos. Quando diferentes critérios de seleção são considerados, a predição de ganhos referentes a cada critério tem grande importância, pois indica os melhoristas sobre como utilizar o material genético disponível, visando obter o máximo de ganhos possível para as características de interesse. O presente trabalho foi instalado em julho de 2004, na Fazenda Experimental de Bananal do Norte, conduzida pelo Incaper, no distrito de Pacotuba, município de Cachoeiro de Itapemirim, região Sul do Estado, com o objetivo de selecionar as melhores plantas entre e dentro de progênies de meios- irmãos de Coffea canephora, por meio de diferentes critérios de seleção. Foram realizadas análises de variância individuais e conjuntas para 26 progênies de meios- irmãos Coffea canephora. O delineamento experimental utilizado foi em blocos ao acaso com quatro testemunhas adicionais com quatro repetições e parcela composta por cinco plantas, com o espaçamento de 3,0 m x 1,2 m. Neste trabalho, considerou-se os dados das últimas cinco colheitas. As características mensuradas foram: florescimento, maturação, tamanho do grão, peso, porte, vigor, ferrugem, mancha cercóspora, seca de ponteiros, escala geral, porcentagem de frutos boia e bicho mineiro. Todas as análises estatísticas foram realizadas com o aplicativo computacional em genética e estatística (GENES). Foram estimados os ganhos de seleção em função da porcentagem de seleção de 20% entre e dentro, sendo as mesmas mantidas para todas as características. Todas as características foram submetidas a seleção no sentido positivo, exceto para florescimento, porte, ferrugem, mancha cercóspora, seca de ponteiros, porcentagem de frutos boia e bicho mineiro, para obter decréscimo em suas médias originais. Os critérios de seleção estudados foram: seleção convencional entre e dentro das famílias, índice de seleção combinada, seleção massal e seleção massal estratificada. Esta dissertação é composta por dois capítulos, em que foram realizadas análises biométricas, como a obtenção de estimativas de parâmetros genéticos. Na maioria das características estudadas, verificaram-se diferenças significativas (P<0,05) para genótipos que, associados aos coeficientes de variação genotípicos e também ao coeficiente de determinação genotípico e à relação CVg/CVe, indicam a existência de variabilidade genética nos materiais genéticos para a maioria das características e condições favoráveis para obtenção de ganhos genéticos pela seleção. Essas características também foram correlacionadas. Os dados foram submetidos às análises de variância e multivariada, aplicando-se a técnica de agrupamento e UPGMA, teste de médias e estudo de correlações. Na técnica de agrupamento, foi utilizada a distância generalizada de Mahalanobis como medida de dissimilaridade, e na delimitação dos grupos, o método de Tocher. Foi encontrada diversidade genética para as características associadas à qualidade fisiológica, mobilização de reserva das sementes, dimensões e biomassa das plântulas. Quatro grupos de genótipos puderam ser formados. Peso de massa seca de sementes, redução de reserva de sementes e peso de massa seca de plântulas estão positivamente correlacionados entre si, enquanto a redução de reserva das sementes e a eficiência na conversão dessas reservas em plântulas estão negativamente correlacionadas. De acordo com os resultados obtidos, verificou-se que todas as características apresentaram níveis diferenciados de variabilidade genética e os critérios de seleção utilizados mostraram-se eficientes para o melhoramento, no qual o índice de seleção combinada é o critério de seleção que apresentou os melhores resultados em termos de ganhos, sendo indicado como critério mais apropriado para o melhoramento genético da população estudada. Nos estudos de correlações, em 70% dos casos, a correlação fenotípica foi superior à genotípica, mostrando maior influência dos fatores ambientais em relação aos genotípicos e condições propícias ao melhoramento dos diferentes caracteres. No estudo de divergência genética, observou-se que pelo agrupamento de genótipos, pela técnica de Tocher, indicou que os genótipos foram distribuídos em três grupos.

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In order to select superior hybrids for the concentration of favorable alleles for resistance to papaya black spot, powdery mildew and phoma spot, 67 hybrids were evaluated in two seasons, in 2007, in a randomized block design with two replications. Genetic gains were estimated from the selection indices of Smith & Hazel, Pesek & Baker, Williams, Mulamba & Mock, with selection intensity of 22.39%, corresponding to 15 hybrids. The index of Mulamba & Mock showed gains more suitable for the five traits assessed when it was used the criterion of economic weight tentatively assigned. Together, severity of black spot on leaves and on fruits, characteristics considered most relevant to the selection of resistant materials, expressed percentage gain of -44.15%. In addition, there were gains for other characteristics, with negative predicted selective percentage gain. The results showed that the index of Mulamba & Mock is the most efficient procedure for simultaneous selection of papaya hybrid resistant to black spot, powdery mildew and phoma spot.

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RESUMO: A utilização adequada das TIC no ensino da Matemática, nos dias de hoje é considerada por alguns como justificada e inevitável, esperando que a sua utilização melhore o ensino e a aprendizagem da Matemática. Nesta investigação, pretende-se testar o Software Winplot), no ensino e aprendizagem do gráfico da função quadrática com alunos do 10ºano, da Escola do segundo ciclo do Ensino Secundário nº9099, de modo a verificar se melhora o ensino e na aprendizagem desta temática.Para a nossa investigação Seleccionámos dois grupos de alunos do 10º ano que funcionaram como grupo de controlo e grupo experimental; depois de ambos os grupos terem realizado dois pré-testes, o grupo experimental realizou as aprendizagens no laboratório de informática com auxílio do Software Winplot, ao longo de 8 semanas, durante o 2º trimestre do ano lectivo de 2009/2010. O grupo de controlo realizou as aprendizagens, ao mesmo tempo que o grupo experimental, na sala normal de aulas sem auxílio do Software Winplot.Ao compararmos os dois grupos, o teste T de pares para amostras independentes, mostra-nos que estatisticamente não há diferenças significativas entre os dois grupos, porque os níveis de significância são maiores que p=0,05, desta feita podemos dizer que o grupo experimental, não obteve melhores resultados que o grupo de controlo, logo o Software Winplot não resultou o efeito desejado nas aprendizagens com alunos da 10ºano da Escola do segundo ciclo do ensino Secundário nº9099, sita no município de Viana (Luanda/Angola). ABSTRACT:The appropriate use of ICTs in teaching mathematics, today is considered by somo to be justified and inevitable, hoping that their use will improve the teaching and learning of mathematics.In this investigation, we intend to test the Software Winplot, teaching and learning of the graph of quadratic functions with students of grade 10, attending the second cycle of secondary School nº9099 in order to verify that improves teaching and learning of this subject.For our research selected two groups of students in 10th grade who acted as the controlo group and experimental group, after both group had undergone two pre-test, the experimental group performed the learning in the computer lab with the aid of Software Winplot, over 8 weeks during the second quarter of the academic year 2009/2010. Thr control gropu performed the learning, while the experimental group, in rregular class room without help of the Software Winplot.Comparing the two groups, the t test for independent samples pairs, shows us that there is no statistically significant differences between the two groups, because the significance levels are greater than p=0,05, this time we can say that experimental group, not yielded better results than the control group, so the Software did not result the desired effect on the learning with students from 10th grade of the School of the second cycle of Secondary nº9099, located in Viana (Luanda/Angola).

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Do ponto de vista das preocupações de saúde, os níveis de contaminação do ar interior assumem actualmente uma elevada importância quando se tem em consideração que as pessoas passam a maior parte do seu tempo no interior de edifícios. Neste contexto, o formaldeído é um dos poluentes mais preocupantes e, inclusivamente, os resultados de concentração obtidos em habitações do espaço Europeu foram considerados preocupantes devido ao facto de estarem relacionados com efeitos negativos para a saúde. O estudo exploratório desenvolvido pretendeu disponibilizar informação acerca das concentrações de formaldeído existentes em habitações domésticas portuguesas. Estudou‑se a presença de formaldeído em habitações novas e habitações domésticas com ocupação, abrangendo 6 unidades de cada um dos tipos considerados. Para a avaliação ambiental foi utilizado um equipamento de leitura direta que deteta as concentrações de formaldeído por fotoionização com uma lâmpada de 11,7 eV. A temperatura ambiente e a humidade relativa foram igualmente medidas, de acordo com o estipulado na Norma Internacional ISO 7726:1998. No caso das habitações novas foram registados valores de concentração superiores a 0,08 ppm em 3 das unidades estudadas. Por outro lado, em 4 das habitações com ocupação foram obtidos valores superiores a 0,08 ppm. O desenvolvimento deste estudo permitiu reconhecer algumas das possíveis fontes emissoras e os factores que influenciam as concentrações de formaldeído nas habitações em Portugal. ABSTRACT - Nowadays, indoor air contamination is considering an important health issue considering that people spend most of their time indoors. In this context, formaldehyde is a pollutant of major concern and, recently, concentration results obtained in European dwellings reveal high concentrations and values related with negative health effects in occupants. The present exploratory study sought to provide information about formaldehyde concentrations in Portuguese dwellings. It was studied formaldehyde presence in new dwellings and dwellings with occupation and included 6 units of each setting. For concentrations measure, it was used a direct‑reading equipment that detects formaldehyde concentration by photoionization. Temperature and relative humidity were also measured in accordance with International Standard ISO 7726:1998. In the case of new dwellings, in 3 units concentration values were higher than 0.08 ppm. In addition, in 4 units of the 6 dwellings with occupation, concentrations higher than this reference value were obtained. The development of this study permitted to recognize some of the possible indoors emissions sources and to define several of the preventive measures that can be applied.

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Cryptosporidium sp., a coccidian parasite usually found in the faeces of cattle, has been recently implicated as an agent of human intestinal disease, mainly in immunocompromised patients. In the study realized, by an indirect immunofluorescence technique, specific immunoglobulins (IgG and IgM) have been demonstrated in human serum against Cryptosporidium oocysts. Purified oocysts were used as antigens in the indirect immunofluorecence assay. After analyzing this test in sera from selected groups of patients, the frequency of both specific IgG and IgM of immunocompetent children who were excreting oocysts in their faeces was 62% and in children with negative excretion of oocysts was 20% and 40%, respectively. In adults infected with the human immunodeficiency virus (HIV) and who were excreting Cryptosporidium in their stools, the frequency was 57% for IgG but only 2% for IgM. Twenty three percent of immunocompromised adults with not determined excretion of oocysts in their stools had anti-Cryptosporidium IgG in their sera. Children infected with human immunodeficiency virus had no IgM and only 14% had IgG detectable in their sera. The indirect immunoflorescence assay, when used with other parasitological techniques appears to be useful for retrospective population studies and for diagnosis of acute infection. The humoral immune response of HIV positive patients to this protozoan agent needs clarification.

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OBJECTIVE: The expansion of precarious employment in OECD countries has been widely associated with negative health and safety effects. Although many shiftworkers are precariously employed, shiftwork research has concentrated on full-time workers in continuing employment. This paper examines the impact of precarious employment on working hours, work-life conflict and health by comparing casual employees to full-time, "permanent" employees working in the same occupations and workplaces. METHODS: Thirty-nine convergent interviews were conducted in two five-star hotels. The participants included 26 full-time and 13 casual (temporary) employees. They ranged in age from 19 to 61 years and included 17 females and 22 males. Working hours ranged from zero to 73 hours per week. RESULTS: Marked differences emerged between the reports of casual and full-time employees about working hours, work-life conflict and health. Casuals were more likely to work highly irregular hours over which they had little control. Their daily and weekly working hours ranged from very long to very short according to organisational requirements. Long working hours, combined with low predictability and control, produced greater disruption to family and social lives and poorer work-life balance for casuals. Uncoordinated hours across multiple jobs exacerbated these problems in some cases. Health-related issues reported to arise from work-life conflict included sleep disturbance, fatigue and disrupted exercise and dietary regimes. CONCLUSIONS:This study identified significant disadvantages of casual employment. In the same hotels, and doing largely the same jobs, casual employees had less desirable and predictable work schedules, greater work-life conflict and more associated health complaints than "permanent" workers.

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OBJECTIVE: To evaluate physical and psychological dimensions of adolescent labor (such as job demands, job control, and social support in the work environment), and their relation to reported body pain, work injuries, sleep duration and daily working hours. METHODS: A total of 354 adolescents attending evening classes at a public school in São Paulo, Brazil, answered questionnaires regarding their living and working conditions (Karasek's Job Content Questionnaire, 1998), and their health status. Data collection took place in April and May 2001. Multiple logistic regression analysis was used to determine relations among variables. RESULTS: Psychological job demands were related to body pain (OR=3.3), higher risk of work injuries (OR=3.0) and reduced sleep duration in weekdays (Monday to Thursday) (p<0.01). Lower decision authority in the workplace (p=0.03) and higher job security (p=0.02) were related to longer daily working hours. CONCLUSIONS: It was concluded that besides physical stressors, psychological factors are to be taken into account when studying adolescent working conditions, as they may be associated with negative job conditions and health effects.