161 resultados para arbetsrelaterad stress


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This study aimed to identify differences in swine vocalization pattern according to animal gender and different stress conditions. A total of 150 barrow males and 150 females (Dalland® genetic strain), aged 100 days, were used in the experiment. Pigs were exposed to different stressful situations: thirst (no access to water), hunger (no access to food), and thermal stress (THI exceeding 74). For the control treatment, animals were kept under a comfort situation (animals with full access to food and water, with environmental THI lower than 70). Acoustic signals were recorded every 30 minutes, totaling six samples for each stress situation. Afterwards, the audios were analyzed by Praat® 5.1.19 software, generating a sound spectrum. For determination of stress conditions, data were processed by WEKA® 3.5 software, using the decision tree algorithm C4.5, known as J48 in the software environment, considering cross-validation with samples of 10% (10-fold cross-validation). According to the Decision Tree, the acoustic most important attribute for the classification of stress conditions was sound Intensity (root node). It was not possible to identify, using the tested attributes, the animal gender by vocal register. A decision tree was generated for recognition of situations of swine hunger, thirst, and heat stress from records of sound intensity, Pitch frequency, and Formant 1.

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Plants respond to environmental adversities, becoming an indicator for assessing the environment quality. In this aspect, chlorophyll contents as well, carotenoids are used as a reliable indicator to associate environmental quality and pollution, mainly regarding the toxicity of heavy metals in higher plants. So, we aimed to evaluate the content of chlorophyll a, b, and total chlorophylls and carotenoids in plants vetiver [Vetiveria zizanioides (L.) Nash], maize (Zea mays L.) cv. AG 1051, sunflower (Helianthus annuus L.) cv. BRS 122/V-2000, and castor beans (Ricinus communis L. ) cv . Northeastern BRS grown in contaminated soil with lead, with and without correction of soil pH, so they were used as indicators of metal stress by the soil. From the biochemical point of view, the correction of soil pH values caused chlorophyll a, b and total statistically higher for vetiver species and castor beans in the analyzed periods, except for the analysis performed 60 days after transplanting where only the species vetiver benefited from the correction of soil pH on the content of chlorophyll b and total. On the other hand plants without correction of soil pH showed a decrease of all chlorophyll levels. In addition, the largest increase in the synthesis of carotenoids, indicated that under stress the plants have developed alternative routes of dissipation of energy in order to avoid problems of photo-inhibition and photo-oxidation.

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This study aims to evaluate the leaf concentration of nitrogen and phosphorus correlated to the production of photoassimilates in beans plants (Phaseolus vulgaris L.) under high [CO2] and drought stress. The experiment was conducted in Viçosa (Brazil), during the period from April to July 2009, by using open-top chambers equipped with CO2 injection system. The drought stress was applied, through the irrigation suspension, during the period from flowering to maturation. The experimental design was randomized blocks in split-plot scheme with four replication, where the plots with plants grown in [CO2] of 700 mg L-1 and [CO2] environment of 380 mg L-1 and the subplots with plants with and without drought stress. The results were submitted to ANOVA and Tukey test (p < 0.05). In the plants under high [CO2] with and without drought stress, the photosynthetic rate increased by 59%, while the dry matter presented an increment of 20% in the plants under high [CO2] without drought stress. Reductions in [N] and [P] occurred in plants grown under high [CO2], resulting in greater efficiency in nitrogen use for photosynthesis. The high [CO2] increase only the total dry matter and not the total mass of grains. The drought stress reduces the dry matter and mass of grain, even at high [CO2].

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ABSTRACT Given the need to obtain systems to better control broiler production environment, we performed an experiment with broilers from 1 to 21 days, which were submitted to different intensities and air temperature durations in conditioned wind tunnels and the results were used for validation of afuzzy model. The model was developed using as input variables: duration of heat stress (days), dry bulb air temperature (°C) and as output variable: feed intake (g) weight gain (g) and feed conversion (g.g-1). The inference method used was Mamdani, 20 rules have been prepared and the defuzzification technique used was the Center of Gravity. A satisfactory efficiency in determining productive responses is evidenced in the results obtained in the model simulation, when compared with the experimental data, where R2 values ​​calculated for feed intake, weight gain and feed conversion were 0.998, 0.981 and 0.980, respectively.

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OBJECTIVE: to evaluate the impact of stress in patients undergoing major surgeries under general anesthesia, relating their physical and psychic reactions to the different stages of stress. METHODS: we studied 100 adult patients of both genders, who were divided into two groups: Group 1 - 22 patients without experience with surgery; Group 2 - 78 patients previously submitted to medium and major surgery. To investigate the stress, we used the Inventory of Stress Symptoms for Adults, developed by Lipp, the day before the procedure and two days and seven days after the operation. The comparison of groups with respect to gender, pain, and percentage of stress were performed using the Chi-square test, and for the age variable the Student's t test was used. Differences were considered significant at p<0.05. RESULTS: the groups were not homogeneous as for the overall percentage of stress on the three measurements. G1 had decreased postoperative stress, whilst in G2 it increased. Psychological symptoms of stress prevailed in both groups. CONCLUSION: previous surgery reduced preoperative stress but did not affect postoperative emotional disorders.

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Objective: To assess the application of aponeurotic sling by a modified technique with direct visualization of needles in patients with stress urinary incontinence. Methods: we applied the Kings Health Questionnaire (KHQ) for quality of life, gynecological examination, urinalysis I and urine culture approximately seven days prior to the urodynamic study (UDS) and the one-hour PAD test in patients undergoing making aponeurotic sling with its passing through the retropubic route with direct visualization of the needle, PAD test and King's Helth Questionnaire before and after surgery. Results: The mean age was 50.6 years, BMI of 28 and Leak Pressure (LP) 58,5cm H2O; 89% were Caucasian. Forty-six of them were monitored for three and six months, 43 for 12 months. The objective cure rate at 12 months postoperatively was approximately 93.5%. In evaluating quality of life, we observed a significant improvement in 12 months postoperatively compared with the preoperative period. There was no no urethral/bladder injury. As adverse results, we had one persistent urinary retention (2.3%), who was submitted to urethrolysis, currently without incontinence. Conclusion: The proposed procedure is safe as for the risk of bladder or urethral injuries, promoting significant improvement in quality of life and objective cure.

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OBJETIVO: Descrever e comparar as fases do stress de primigestas no terceiro trimestre de gestação e no pós-parto e correlacioná-las à ocorrência de depressão pós-parto (DPP). MÉTODOS: A pesquisa foi constituída de duas etapas, caracterizando-se como pesquisa longitudinal. Na Etapa 1, participaram 98 primigestas e na Etapa 2, 64 delas. Na Etapa 1, a coleta de dados aconteceu no terceiro trimestre de gestação e, na Etapa 2, no mínimo 45 dias após o parto. Na Etapa 1 aplicou-se o Inventário de Sintomas de Stress de Lipp (ISSL) e uma Entrevista Inicial para caracterização da amostra. Na Etapa 2, aplicou-se novamente o ISSL e também a EPDS (Escala de Edimburgo). Os dados foram analisados usando o programa estatístico SPSS for Windows®, versão 17.0. As análises estatísticas efetuadas foram o Teste t de Student e p de Spearman. RESULTADOS: No terceiro trimestre, 78% das participantes apresentaram sinais significativos para stress e, no puerpério, 63% manifestaram, apresentando diferença significativa entre o stress manifestado no terceiro trimestre e no puerpério (t=2,20; p=0,03). Observou-se, também, correlação entre o stress apresentado tanto na gestação como no puerpério e a manifestação de DPP (p<0,001). CONCLUSÃO: Tanto na gestação como no puerpério mais da metade das mulheres apresentam sinais significativos para stress. Entretanto, a frequência da manifestação dos sintomas significativos de stress na gestação foi superior à frequência apresentada no puerpério. Tais resultados parecem guardar uma estreita relação com a manifestação de DPP, indicando relação entre stress e DPP.

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PURPOSE: The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI.METHODS: This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI.RESULTS: We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI.CONCLUSION: We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.

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We performed a systematic review and meta-analysis of randomized controlled trials that studied the conservative management of stress urinary incontinence (SUI). There were 1058 results after the initial searches, from which 37 studies were eligible according to previously determined inclusion criteria. For the primary outcomes, pelvic floor muscle training (PFMT) was more efficacious than no treatment in improving incontinence-specific quality of life (QoL) scales (SMD = [1]1.24SDs; CI 95% = [1]1.77 to [1]0.71SDs). However, its effect on pad tests was imprecise. Combining biofeedback with PFMT had an uncertain effect on QoL (MD = [1]4.4 points; CI 95% = [1]16.69 to 7.89 points), but better results on the pad test, although with elevated heterogeneity (MD = 0.9g; 95%CI = 0.71 to 1,10g); group PFMT was not less efficacious than individual treatment, and home PFMT was not consistently worse than supervised PFMT. Both intravaginal and superficial electrical stimulation (IES and SES) were better than no treatment for QoL and pad test. Vaginal cones had mixed results. The association of IES with PFMT may improve the efficacy of the latter for QoL and pad test, but the results of individual studies were not consistent. Thus, there is evidence of the use of PFMT on the treatment of SUI, with and without biofeedback.

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A complement fixation test (CFT), performed in microtitre plates, based upon the use of crude antigenic preparation of Babesia equi was adapted for the detection of antibodies in serum of infected horses. The indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) were also used for the immunodiagnosis of B. equi. Serum samples from 15 apparently healthy horses, previously conditioned to a high-speed equine treadmill, were taken before and after exercise. All the samples analyzed were positive for B. equi infection. There were no significant differences (P<0.01) between these 3 tests, or the condition of rest or stress. The combined use of CFT and IFAT or ELISA should be recommended in order to enable veterinary services to more efficiently prevent introduction of infected horses into disease-free areas.

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Abstract: Blood samples collection is a common method in biological research using domestic animals. However, most blood sampling techniques are complicated and highly invasive and may therefore not be appropriate for wildlife animals in research concerning stress. Thus, a non-invasive method to measure steroid hormones is critically needed. The first goal of this study was to determine how glucocorticoids concentrations are impacted by translocation and reproductive activity in crab-eating-fox (Cerdocyoun thous) in captivity. The physiological relevance of fecal glucocorticoid metabolites was further validated by demonstrating: (1) The translocation of a male to a females enclosure resulted in a 3.5-fold increase compared to baseline concentrations, (2) changes in adrenocortical activity, as reflected in concentrations of fecal cortisol metabolites during reproduction, gestation and lactation in females foxes, indicating that social interactions resulted in large increases of fecal glucocorticoids metabolites during the reproductive season. From these findings we conclude that fecal samples can be used for the non-invasive assessment of adrenocortical status in crab-eating-fox.

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An experimental investigation is performed in a turbulent flow in a seven wire-wrapped rod bundle, mounted in an open air facility. Static pressure distributions are measured on central and peripheral rods. By using a Preston tube, the wall shear stress profiles are experimentally obtained along the perimeter of the rods. The geometric parameters of the test section are P/D=1.20 and H/D=15. The measuring section is located at L/D=40 from the air inlet. It is observed that the dimensionless static pressure and wall shear stress profiles are nearly independent of the Reynolds number and strongly dependent of the wire-spacer position, with abrupt variations of the parameters in the neighborhood of the wires.

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The objective of this study was to evaluate the competitiveness of two cultivars of upland rice drought-tolerant, cultured in coexistence with weed S. verticillata, under conditions of absence and presence of water stress. The experiment was conducted in a greenhouse at the Experimental Station of the Universidade Federal de Tocantins, Gurupi-TO Campus. The experimental design was completely randomized in a factorial 2 x 2 x 4 with four replications. The treatments consisted of two rice cultivars under two water conditions and four densities. At 57 days after emergence, were evaluated in rice cultivars and weed S. verticillata leaf area, dry weight of roots and shoots and total concentration and depth of roots. Was also evaluated in rice cultivars, plant height and number of tillers. Water stress caused a reduction in leaf area, the concentration of roots and vegetative components of dry matter (APDM, and MSR MST) of rice cultivars and Jatoba Catetão and weed S. verticillata. The competition established by the presence of the weed provided reduction of all vegetative components (MSPA, and MSR MST) of cultivars and Jatoba Catetão. It also decreased the number of tillers, the concentration of roots and leaf area. At the highest level of weed competition with rice cultivars, a greater decrease in vegetative components and leaf area of culture, regardless of water conditions.

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Due to the increase of water deficiency in many farm regions and its meaning on weed interference, competitive interactions between soybean and three weeds were evaluated under water stress (20 to 40 days after transplanting) and no stress conditions. Three independent experiments were carried out in a growth chamber, being each one composed by the weeds Alternanthera tenella, Tridax procumbens or Digitaria ciliaris, along with the crop, in which soil water condition and plant composition effects were evaluated while in competition. A replacement series system was used, including both monoculture of each species and a mixture with a ratio of 50% between weed and soybean. A completely randomized design was used in factorial arrangement, with treatments distributed in three levels for plant composition factor (soybean and weeds monocultures, in addition to the soybean + weed mixture) and two levels for the water factor (with or without stress), amounting six treatments in each experiment. Soybean dry mass was higher than weed dry mass, when growing without water stress. However, under water stress conditions, the dry mass of soy was reduced in all experiments, mainly in the D. ciliaris comparative experiment. Water restriction was also significant in the plants' photosynthesis reduction in most of the experiments, reducing leaf area duration and efficiency of water use. Analysing all variables shows greater weed tolerance than soybean when submitted to water deficit and with distinct changes of their interactions and mechanism of competition, in each experiment.

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The volatile oils extracted from the roots of Polygala extraaxillaris were analyzed to assess whether they increase oxidative stress in Brachiaria decumbens var. Piatã, as well as to assess their effect on cellular division and cytotoxicity in laboratory. Six concentrations were used (0%, 0.35%, 0.65%, 1.25%, 0.65%, and 5.0%) with four repetitions of 25 seeds. The substance 1-(2-hydroxyphenyl) - ethanone was identified as the major constituent of the volatile oils. The results showed that the highest concentrations of the oils resulted in an increase in the oxidative stress in B. decumbens, as well as alteration in germination and growth, with a consequent reduction in the process of cellular division, causing changes in the growth standard and antioxidant defense.