Top PDF A BSTRACT - The aim of this study was to describe the composition and

A BSTRACT - The aim of this study was to describe the composition and

A BSTRACT - The aim of this study was to describe the composition and

On the other hand, the representatives of the Chydoridae family virtually disappeared in the months of highest rainfall (> 30 mm), especially when considering the subfamily Chydorinae. A reduction in the number of taxa in the subfamily Aloninae was also recorded, with only the non-planktonic species Karualona muelleri and Oxyurella longicaudis being recorded. These months coincided with noticeable reductions in macrophyte banks, with prevalence only of aggregates of the algae Chara martiana Wallman. Whereas rainfall is scarce in semiarid regions, its sporadic occurrence in greater volume (> 30 mm) in the Caatinga could act on reducing the macrophyte banks, as already observed for other temporary ponds in the Caatinga (Pedro et al., 2006). According to these authors, the richness of aquatic macrophyte communities is lower in temporary ponds during flood events, and this fact could explain the reduction in Chydoridae species in the Mata da Pimenteira pond, a typically dominant family in terms of species richness in several Brazilian shallow ponds with predominance of macrophytes (Table 4). Moreover, taking into account the visual predominance of Chara martiana in Mata da Pimenteira pond, and considering that cladoceran composition varies with macrophyte size (Lauridsen et al., 1996), the slender folioles of this alga would not be sufficient to maintain Chydoridae populations during the periods when the pond is flooded.
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ABSTRACT: The aim of this study was to evaluate the performance of pedotransfer functions

ABSTRACT: The aim of this study was to evaluate the performance of pedotransfer functions

REC curves were constructed following the steps proposed by Mittas and Angelis (2010): 1 – The model was set up, and the error in the predictions was evalu- ated; 2 – The error values were sorted in ascending or- der; 3 – For each error value that was not repeated, a point with the error value and the percentage of points with smaller errors were included in the graph. Step 1 was not necessary because we used available PTFs (Ta- ble 1). The RMSE was used as a measurement of error. Comparisons between curves were also made, by apply- ing the Wilcoxon signed rank test at the 0.05 level, with the Holm correction for multiple comparisons. This test assesses whether population mean ranks differ (paired difference test).
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The aim of this study was to evaluate the mutagenicity (clastogenicityaneugenicity) of a glycolic extract of Ziziphus

The aim of this study was to evaluate the mutagenicity (clastogenicityaneugenicity) of a glycolic extract of Ziziphus

The PCE/NCE ratio is an indicator of the acceleration or inhibition of erythropoiesis and varies with the scoring interval. A continuous decline in the PCE/NCE ratio may reflect the inhibition of cell division, the killing of erythro- blasts, the removal of damaged cells, or dilution of the ex- isting cell pool with newly formed cells (Venkatesh et al., 2007). Several mechanisms may contribute to the cytoto- xicity of DXR and MN induction (Gewirtz, 1999), includ- ing the intercalation of DXR in cellular DNA (Painter, 1978; Kiyomiya et al., 2001), stabilization of the topoi- somerase II-DNA complex (Pommier et al., 1985; Guano et al., 1999), free radical-mediated toxicity caused by redox cycling of the semiquinone radical (Bachur et al., 1979), or the formation of reactive oxygen species by the DXR-iron complex (Eliot et al., 1984; Myers, 1998; Konorev et al., 1999). On the other hand, chemicals such as captopril and desferrioxamine (Al-Harbi, 1993; Al-Shabanah, 1993), b- carotene and vitamins A, C and E (Lu et al., 1996; Gulkac et al., 2004; Costa and Nepomuceno, 2006), thiol N-acetyl- cysteine, probucol, lovastatin and hydrophilic flavonoids such as rutin and luteolin (Al-Gharably, 1996; Sadzuka et al., 1997; D’Agostini et al., 1998; Bardeleben et al., 2002) can also reduce DXR-induced MN formation, genotoxicity and cytotoxicity. However, proponents of herbal medicine always claim that mixtures are better than pure chemicals because the dozens of biologically active compounds in plants work together to produce a greater effect than any one chemical on its own (Mackenzie, 2001).
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The aim of this study was to establish reference concentrations (LC 50

The aim of this study was to establish reference concentrations (LC 50

This species is usually found at damp and shaded places such as gardens and vegetable gardens (Aráujo and Bessa 1993). When it occurs at high densities, the control of this species becomes necessary in order to reduce the damages caused in crops. Besides, S. octona is a great experimental model for laboratory studies, due to some characteristics of its life cycle such as fast sexual maturity, short incubation period, high hatchability, high reproductive rates (Bessa and Araújo 1995a, b) and homogeneous growth (D’ávila and Bessa 2005a) making easy the analysis of substances with molluscicidal effect.
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Abstract The aim of this study is to identify the

Abstract The aim of this study is to identify the

Abstract The aim of this study is to identify the prevalence of pregnancy and abortion experience, along with associated factors among street chil- dren, adolescents and youths in Porto Alegre and Rio Grande, RS, Brazil. The sampling method in this cross-sectional study was Respondent-Driven Sampling (RDS), innovative in research about hidden populations. Interviews were conducted with 307 subjects, aged 10 to 21 years. In multi- variate analysis, Poisson regression with a robust error variance was used. Most of this sample were males, with no contact with school and family. Almost half of the participants had been on the street for five years or more, spending more than 15 hours per day on the streets. The prevalence of pregnancy experience was 29.3%, independent- ly associated with being a girl, having 10 sexual partners or more in the last year, having a fixed sexual partner in the last year, and being older. The prevalence of abortion experience was 10.4%, independently associated with not living with the family, having more than two pregnancies, and being younger. The high prevalence of pregnancy and abortion experience highlights the need for the development of better sexual and reproductive health policies focused on this population. Key words Pregnancy, Abortion, Street adoles- cents, Street youth, Teenage pregnancy
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Abstract - the aim of this study was to evaluate the chemical characteristics and sensory

Abstract - the aim of this study was to evaluate the chemical characteristics and sensory

Abstract - the aim of this study was to evaluate the chemical characteristics and sensory acceptance of juices and cuts of ‘Bordô’ and ‘Niágara Rosada’ grapes. The experimental design was in a one-factor scheme, with five levels. Treatments were: T1 – ‘Bordô’ (100%); T2 – ‘Bordô’ (70%) + ‘Niágara Rosada’ (30%); T3 – ‘Bordô’ (50%) + ‘Niágara Rosada’ (50%); T4 – ‘Bordô’ (30%) + ‘Niágara Rosada’ (70%); T5 – ‘Niágara Rosada’ (100%). Chemical analyses were: content of soluble solids, pH and titratable acidity, and sensory analyses were: color, aroma, flavor, body and global acceptance. For the soluble solids content, the highest averages were verified in T1, T2 and T3 treatments. As for pH, the highest value was recorded in T3, T4 and T5 treatments, while the highest titratable acidity was recorded in T4 and T5 treatments. In the sensory analysis, in juice with the highest percentage of ‘Bordô’ grape (T1 and T2) or with the same proportion of ‘Bordô’ and ‘Niágara Rosada’ (T3), the highest mean acceptance values were found. Thus, it could be concluded that the use of 100% ‘Bordô’ grape and ‘Bordô’ juice cut with up to 50% ‘Niágara Rosada’ are presented as alternatives for juice production.
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The aim of this study was to evaluate changes in carcass traits according to slaughter weight

The aim of this study was to evaluate changes in carcass traits according to slaughter weight

present study the correlation coefficient (r) between commercial dressing percentage and gastrointestinal content (12.33, 19.29, 19.20 and 18.52%, respectively for SW, S25, S30 and S35) was -0.87. Low gastrointestinal content for SW can be related to lack of rumen development and, consequently, to low intake of a solid diet (PIRES et al., 2000; KREMER et al., 2004). Otherwise, commercial dressing percentage increases as slaughter weight increases and it is related to high rate of fat deposition at maturity (ROSA et al., 2005). REID & ROBB (1971) speculated that accumulation of fat reduces the volume available for the digestive tract and, consequently, would decrease feed intake and gastrointestinal content. In fact, more recent studies have suggested that feed intake decreases as fat accretion, but it is due to higher leptin secretion by adipose tissue (INGVARTSEN & BOISCLAIR, 2001; EHRHARDT et al., 2003). However, in our study different feed intake among the groups evaluated was not verified (P>0.05), suggesting that highest fat deposition at more elevated slaughter weights, as indicated by increased subcutaneous fat thickness, is the mainly characteristic determining the commercial dressing percentage.
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Abstract This study aims to describe the prev-

Abstract This study aims to describe the prev-

Abstract This study aims to describe the prev- alence of heavy drinking, high-risk alcohol con- sumption and associated factors among tobacco farmers. A cross-sectional study was carried out with 2,469 tobacco farmers over 18 years old in 2011. High-risk alcohol consumption was consid- ered the intake of three or more standard doses per day for men or two or more for women. Heavy drinking was considered the intake of four or more standard doses per day for men and three or more for women. Hierarchical multivariate analysis was performed to investigate the associa- tion with socioeconomic, behavioral, and occupa- tional variables. Results: The prevalence of high- risk and heavy drinking was of 4.7% and 1.09% among women and 30.8% and 4.8% among men, respectively. The factors associated with high-risk drinking for men and women were the percentage of income tobacco accounted for (PR 1.3 and 0.4), being an employee (PR 1.3 and 3.1), and use of pesticides (PR 1.5 and 2.1), respectively. Heavy drinking among men was associated with losing the crop (PR 1.6), attending religious activities (PR 0.3), and hours working in agriculture (PR 0.6). Occupational factors were associated wit high-risk alcohol consumption among men. The associated factors vary according to the pattern of consumption assessed.
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Objective: The aim of the present study was to investigate the depressive symptoms and

Objective: The aim of the present study was to investigate the depressive symptoms and

The investigation of depression, peripheral neurotrophic and cortisol parameters in ostomy patients is still poorly descri- bed. This is the first study to provide evidence of a significant BDNF decrease and NT-3 increase in the serum from ostomy patients, when compared to control group. These alterations were associated with psychological and social complications. In addition, the data showed an increase only in the HDRS, which is a scale for measuring the depressive symptoms levels, the SCID-I instrument is already used for diagnosing psychiatric disorders. Thus, ostomy patients did not have a MDD diagnosis, but presented a depressive symptoms improvement when compared to healthy controls 25 .
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The influence of the arc plasma treatment on the structure and microhardness C120U carbon tool steel

The influence of the arc plasma treatment on the structure and microhardness C120U carbon tool steel

The material used in this study was C120U steel. Chemical composition of this steel is presented in Table 1. Specimens as cuboids about dimensions 7,5 x 30 x 30 mm were conventional hardened (temperature austenitization – 770 o C, quenching in oil) and tempered (in temperature 250 o C). Temperatures hardening and tempering were chosen on the basis EN ISO 4957:1999 norms to obtain a structure with a relatively high toughness. Remelting surface was carried out using gas tungsten arc welding method. The surface of the samples were remelted by means of
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Abstract The aim of this study was to analyze

Abstract The aim of this study was to analyze

An attempt was made to ensure that the dis- tribution of students in the sample was balanced concerning the geographical allocation of stu- dents, school size and the period of the day that students attended school. The number of stu- dents enrolled in each of the 17 school districts, which are political organizations responsible for managing schools belonging to their territory, determined the Geographical distribution. We divided School size into three categories accord- ing to the number of students attending each high school as follows: small, < 200; medium, 200 to 499; and large, ≥ 500 and period of the day that students attended school in two categories: daytime and evening.
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Abstract The aim of this study is to describe in-

Abstract The aim of this study is to describe in-

Abstract The aim of this study is to describe in- cipient tobacco use and associated factors among adolescents from the rural zone of southwestern Bahia. It was based on data from the cross-sec- tional Adolescer research project among 390 ad- olescents conducted in 2015. Data were analyzed using frequency and chi-square measurements and Poisson regression with robust variance to es- timate the prevalence ratios (PR) for incipient to- bacco use in relation to the explanatory variables. Among the adolescents, 5.1% had smoked at some stage and 0.3% smoked regularly. The following variables were associated with incipient smoking: male gender (PR = 6.46); having had sexual in- tercourse at some stage in life (PR = 20.55); hav- ing parents who rarely or never understood their problems (PR=7.89); having 3 or more friends (PR = 0.10). Despite low incipient smoking or the prevalence of regular smoking, which indicate the adoption of a healthier lifestyle or greater autono- my and decision-making ability for non-smoking, it is acknowledged that there is no safe level of ex- posure to tobacco. The recommendation is that an intersectoral partnership between education and health be created to foster health promotion and disease prevention, with an emphasis on curtail- ing smoking habits.
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Abstract The scope of this study was to describe

Abstract The scope of this study was to describe

Abstract The scope of this study was to describe the prevalence of depressive symptoms measured by the Geriatric Depression Scale–EDG - 15 and test the association of oral health variables and depressive symptoms in a population of the elderly linked to eleven Family Health Units in the south of Brazil. It involved a cross-sectional study with 439 elderly individuals. A standardized question- naire was used to obtain socio-economic and oral health variables of the study. The clinical variables of oral health were obtained by a qualified den- tist. The symptoms of depression, which was the scope of the study, were obtained by the Geriatric Depression Scale–EDG -15. The prevalence of de- pressive symptoms was 18.3% (CI95% 14.6-21.8). Analyzing the exposure variables and depressive symptoms through adjusted Poisson regression analysis, individuals with 1 to 9 teeth (PR = 1.68; CI95% 1.06-2.64, p = 0.012), with a perception of dry mouth (PR = 2.23; CI95% 1.52-3.28, p < 0.001) and perception of pain in the mouth (PR = 2.11; CI95% 1.10-4.07, p = 0.036) have a high- er prevalence of depressive symptoms. The study identified a significant prevalence of depressive symptoms and that oral health variables are as- sociated with the presence of depressive symptoms in the elderly population.
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Abstract The aim of this study was to assess the

Abstract The aim of this study was to assess the

The significance test for the generalized mod- el obtained a p-value of ≤ .000, indicating that the model was significant. The significance value for each of the predictor variables SE, IM and DS was less than .05, showing that they were rele- vant. It is interesting to note from the results that normal/high levels of SE inhibit the likelihood of SI, while, conversely, high levels of IM and DS increase the likelihood. The ORs obtained there- fore suggest that high levels of IM result in a two- fold increase (OR = 1.907) in the likelihood of SI. Without doubt, however, the result that stands out most is the fact that the presence of DS leads to a ninefold increase in the likelihood of SI (OR = 9.006), corroborating the theory that high lev- els of depression are conducive to suicidal ide- ation and, ultimately, attempted suicide.
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Abstract The aim of this study was to assess the

Abstract The aim of this study was to assess the

Abstract The aim of this study was to assess the presence of suicidal ideation and depressive symp- toms among adolescents in Chiapas, Mexico based on predictor variables. A cross-sectional study adopting an ex post facto design was conducted with a non-probability sample of 4,759 students of both sexes with an average age of 18.4 years and using the following tools: the Center for Epidemi- ologic Studies Depression Scale, Roberts’ Suicidal Ideation Scale, the Impulsiveness Scale (IS), and the Rosenberg Self-Esteem Scale. The mean score obtained by the suicidal ideation scale was 0.2, which is lower than that reported by other studies, while the mean score for depressive symptoms was similar to those in the literature. The prevalence of suicidal ideation was 7.8%, which is lower than reported in national and international studies. Multivariable logistic regression showed that im- pulsiveness (OR = 1.907) and depressive symp- toms (OR = 9.006) lead to a twofold and ninefold increase in the likelihood of suicidal ideation, re- spectively. The findings also showed a strong asso- ciation between suicidal ideation and depressive symptoms, showing that the latter is a predictor of suicidal ideation among adolescents.
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Abstract The aim of this study was to assess the

Abstract The aim of this study was to assess the

Abstract The aim of this study was to assess the prevalence of being underweight among the elder- ly according to demographic and socioeconomic characteristics, health-related behaviors, diseas- es and health status. This was a cross-sectional multi-center study with 3,478 community-dwell- ing elders (≥ 65 years). The dependent variable was the prevalence of being underweight, classified by Body Mass Index < 22kg/m2. Adjusted preva- lence rate ratios were estimated using multivari- able Poisson regression. The mean age was 72.9 years and 12.0% of the elderly were underweight (CI95%:10.9-13.1). Aged elderly ≥ 80 years, for- mer and current smokers, those who reported ap- petite loss and those classified as pre-frail or frail (PR=1.41; CI95%:1.09-1.82) presented a higher prevalence of being underweight. Individuals who received medical diagnosis of hypertension, diabe- tes and rheumatism had the lowest underweight prevalence observed. The results highlight the importance of nutritional status assessment and monitoring among the elderly, with emphasis on the most vulnerable subgroups, particularly the frail elderly, taking into account the health conse- quences of low weight.
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Abstract The aim of this study was to compare

Abstract The aim of this study was to compare

The Spearman correlation between the WHOQOL-Bref domains (Physical, Psycholog- ical, Social Relations, and Environment) and global QOL, considering the total number of elderly individuals, showed that all domains correlated positively and significantly with the global domain, although the correlations are of low magnitude. Thus, multiple linear regression analysis was performed to verify the contribution of each domain to the global QOL (dependent variable); the four domains together account for 40.5% of the global QOL. The Social Rela- tions domain presented the lowest contribution (6.0%), followed by Psychological (7.5%) and Environment (9.9%), not presenting statistical significance. The domain that most impacted on the overall QOL is the Physical domain (17.1%), with a statistically significant difference (Table 4). Table 5 presents the estimates of the Spear- man correlation coefficients between the WHO- QOL-Old dimensions (Sensory Skills, Autonomy, Past, Present, and Future Activities, Social Partic- ipation, Death and Dying, and Intimacy) and the OLD general score, considering the 48 elderly, demonstrating that all dimensions correlated
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Fields of study and the earnings gap by race in Brazil

Fields of study and the earnings gap by race in Brazil

The aim of this paper is to investigate the labor earnings differential between white and black workers with a bachelor ’s or graduate degree in Brazil, decomposing this gap into components accounted for by observable differences across individuals, and differences in the return on these characteristics. The empirical analysis uses data from the 2000 and 2010 Brazilian Census. This survey, conducted by the Brazilian Census Bureau (IBGE), has information about labor market and field of study for those who have tertiary education, in addition to demographic characteristics of the individuals. The empirical strategy is based on decompositions of the mean labor earnings difference between white and black workers using the traditional Oaxaca- Blinder methodology (Oaxaca, 1973 and Blinder, 1973), and decompositions for different quantiles of the earnings distribution, through the method proposed by Fortin, Lemieux and Firpo (2009). This way, not only the racial earnings gap could be attributed to differences in the distribution of observable characteristics, and in the returns on these characteristics, but also the former component can be decomposed into contributions associated with individual’s distribution across fields of study, mismatch between education and occupation, attainment of a graduate degree and demographic variables. And this could be done for different percentiles of the earnings distribution.
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The aim of this research was to evaluate the performance of Japanese quail (Coturnix

The aim of this research was to evaluate the performance of Japanese quail (Coturnix

Due to energy costs, the poultry production systems are looking for technologies to rationalize energy use, such as the use of LEDs (light emitting diode), which can be used in poultry cutting and laying (Borille et al., 2013, Santana et al., 2014) and in quail production (Jácome et al., 2012, Molino et al., 2015). More efficient, cheaper and more durable lamps, such as LEDs, which can reduce energy consumption, are possible to adapt to the spectral sensitivity (vision) curve of the birds, providing adequate brightness and increased photoperiod, which for the egg production in quails should be, on average, from 14 to 17 hours of day -1 light, providing a greater production and
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The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

Pouring temperature belongs to very important factors in obtainment of correct results of the modification. Hypereutectoid silumins are characteristic of good castability even in temperatures close to liquidus curve, what suggests implementation of low temperature of casting. However, such method of casting creates conditions to easy coarsening of primary crystals of silicon and their non-uniform distribution on microstructure of the casting. Rate of cooling of the alloy poured into mould has also an effect on results of the modification.
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