Dry matter production of Tanzania grass as a function of agrometeorological variables

The objective of this work was to develop and validate linear regression models to estimate the production of dry matter by Tanzania grass (Megathyrsus maximus, cultivar Tanzania) as a function of agrometeorological variables. For this purpose, data on the growth of this forage grass from 2000 to 2005, under dry-field conditions in Sao Carlos, SP, Brazil, were correlated to the following climatic parameters: minimum and mean temperatures, degree-days, and potential and actual evapotranspiration. Simple linear regressions were performed between agrometeorological variables (independent) and the dry matter accumulation rate (dependent). The estimates were validated with independent data obtained in Sao Carlos and Piracicaba, SP, Brazil. The best statistical results in the development and validation of the models were obtained with the agrometeorological parameters that consider thermal and water availability effects together, such as actual evapotranspiration, accumulation of degree-days corrected by water availability, and the climatic growth index, based on average temperature, solar radiation, and water availability. These variables can be used in simulations and models to predict the production of Tanzania grass.

SPATIAL PATTERN OF FOUR FOREST COMMUNITIES BY RIPLEY'S K FUNCTION IN SAO PAULO STATE

Investigating tree's spatial patterns according to their size classes and according to their more abundant species can provide evidences about the structure of the vegetal community, since the spatial pattern is a key question for forestry ecology studies. The tree spatial organization patterns on the environment depend on several ecological processes and on the specific characteristics of each environment, so that the best understanding of this frame provides important elements for the knowledge on forestry formation. This paper aimed to study tree spatial patterns, according to the diameter classes and from four most abundant species in different forests, in order to provide evidences regarding to the ecology of each vegetal community. The spatial pattern description in each forestry formation was developed using Ripley's K function. The studied forestry formations were: Ombrophilous Forest, Cerradao, Seasonal Forest and Restinga Forest. In this work, a 10.24 ha plot was installed in each forestry formation, and every tree, with a circumference at breast height (CBH) larger than 15 cm were measured, georeferenced and identified. The obtained data highlights the aggregated character in tropical forests, as observed in every studied forest. The 'Cerraddo' and 'Restinga' forest trees showed close aggregate patterns. In the Ombrophilous forest, for all distance scales, the aggregate pattern was meaningful. In the seasonal forest, a random tendency was observed, although a meaningful aggregation was observed in all short distances. The spatial pattern by diameter classes was generally aggregated for trees smaller than 10 cm of diameter and between 10 and 20 cm and random for the others, proving the existence of a tendency which in young trees is more aggregated than in old ones. The spatial pattern of the dominant species is always strongly similar to the general pattern of each forestry formation. The differences between the spatial patterns of two or three coincident species, among the forestry formations, indicate that its pattern is influenced by each different environment. This stands out the importance of its self-ecology and of its ecological processes, intrinsic of each community that can explain the observed patterns.

Fish Oil Supplementation Reduces Cachexia and Tumor Growth While Improving Renal Function in Tumor-Bearing Rats

The objective of the present work was to study the renal function of healthy and tumor-bearing rats chronically supplemented with fish oil (FO), a source of n-3 polyunsaturated fatty acids. Weanling male rats were divided in two groups, one control (C) and another orally supplemented for 70 days with FO (1 g/kg body weight). After this time, half the animals of each group were injected in the right flank with a suspension of Walker 256 tumor cells (W and WFO). The W group had less proteinemia reflecting cachectic proteolysis, FO reversed this fact. Tumor weight gain was also reduced in WFO. Glomerular filtration rate (GFR) was not different in FO or W compared to C, but was higher in WFO. Renal plasma flow (RPF) was higher in the FO supplemented groups. The W group had lower plasma osmolality than the C group, but FO supplementation resulted in normalization of this parameter. Fractional sodium excretion (FENa+) of FO rats was similar to C. Proximal Na+ reabsorption, evaluated by lithium clearance, was similar among the groups. Urinary thromboxane B-2 (TXB2) excretion was lower in the supplemented groups. The number of macrophages in renal tissue was higher in W compared to C rats, but was lower in WFO rats compared to W rats. In conclusion, FO supplementation resulted in less tumor growth and cachexia, and appeared to be renoprotective, as suggested by higher RPF and GFR.

A model of road effect using line integrals and a test of the performance of two new road indices using the distribution of small mammals in an Atlantic Forest landscape

Effects of roads on wildlife and its habitat have been measured using metrics, such as the nearest road distance, road density, and effective mesh size. In this work we introduce two new indices: (1) Integral Road Effect (IRE), which measured the sum effects of points in a road at a fixed point in the forest; and (2) Average Value of the Infinitesimal Road Effect (AVIRE), which measured the average of the effects of roads at this point. IRE is formally defined as the line integral of a special function (the infinitesimal road effect) along the curves that model the roads, whereas AVIRE is the quotient of IRE by the length of the roads. Combining tools of ArcGIS software with a numerical algorithm, we calculated these and other road and habitat cover indices in a sample of points in a human-modified landscape in the Brazilian Atlantic Forest, where data on the abundance of two groups of small mammals (forest specialists and habitat generalists) were collected in the field. We then compared through the Akaike Information Criterion (AIC) a set of candidate regression models to explain the variation in small mammal abundance, including models with our two new road indices (AVIRE and IRE) or models with other road effect indices (nearest road distance, mesh size, and road density), and reference models (containing only habitat indices, or only the intercept without the effect of any variable). Compared to other road effect indices, AVIRE showed the best performance to explain abundance of forest specialist species, whereas the nearest road distance obtained the best performance to generalist species. AVIRE and habitat together were included in the best model for both small mammal groups, that is, higher abundance of specialist and generalist small mammals occurred where there is lower average road effect (less AVIRE) and more habitat. Moreover, AVIRE was not significantly correlated with habitat cover of specialists and generalists differing from the other road effect indices, except mesh size, which allows for separating the effect of roads from the effect of habitat on small mammal communities. We suggest that the proposed indices and GIS procedures could also be useful to describe other spatial ecological phenomena, such as edge effect in habitat fragments. (C) 2012 Elsevier B.V. All rights reserved.

Extracytoplasmic function (ECF) sigma factor sigma(F) is involved in Caulobacter crescentus response to heavy metal stress

Background: The alpha-proteobacterium Caulobacter crescentus inhabits low-nutrient environments and can tolerate certain levels of heavy metals in these sites. It has been reported that C. crescentus responds to exposure to various heavy metals by altering the expression of a large number of genes. Results: In this work, we show that the ECF sigma factor sigma(F) is one of the regulatory proteins involved in the control of the transcriptional response to chromium and cadmium. Microarray experiments indicate that sigma(F) controls eight genes during chromium stress, most of which were previously described as induced by heavy metals. Surprisingly, sigma(F) itself is not strongly auto-regulated under metal stress conditions. Interestingly, sigma(F)-dependent genes are not induced in the presence of agents that generate reactive oxygen species. Promoter analyses revealed that a conserved sigma(F)-dependent sequence is located upstream of all genes of the sigma(F) regulon. In addition, we show that the second gene in the sigF operon acts as a negative regulator of sigma(F) function, and the encoded protein has been named NrsF (Negative regulator of sigma F). Substitution of two conserved cysteine residues (C131 and C181) in NrsF affects its ability to maintain the expression of sigma(F)-dependent genes at basal levels. Furthermore, we show that sigma(F) is released into the cytoplasm during chromium stress and in cells carrying point mutations in both conserved cysteines of the protein NrsF. Conclusion: A possible mechanism for induction of the sigma(F)-dependent genes by chromium and cadmium is the inactivation of the putative anti-sigma factor NrsF, leading to the release of sigma(F) to bind RNA polymerase core and drive transcription of its regulon.

Transcranial magnetic stimulation in mild to severe hemiparesis early after stroke: a proof of principle and novel approach to improve motor function

Low-frequency repetitive transcranial magnetic stimulation (rTMS) of the unaffected hemisphere can enhance function of the paretic hand in patients with mild motor impairment. Effects of low-frequency rTMS to the contralesional motor cortex at an early stage of mild to severe hemiparesis after stroke are unknown. In this pilot, randomized, double-blind clinical trial we compared the effects of low-frequency rTMS or sham rTMS as add-on therapies to outpatient customary rehabilitation, in 30 patients within 5-45 days after ischemic stroke, and mild to severe hand paresis. The primary feasibility outcome was compliance with the interventions. The primary safety outcome was the proportion of intervention-related adverse events. Performance of the paretic hand in the Jebsen-Taylor test and pinch strength were secondary outcomes. Outcomes were assessed at baseline, after ten sessions of treatment administered over 2 weeks and at 1 month after end of treatment. Baseline clinical features were comparable across groups. For the primary feasibility outcome, compliance with treatment was 100% in the active group and 94% in the sham group. There were no serious intervention-related adverse events. There were significant improvements in performance in the Jebsen-Taylor test (mean, 12.3% 1 month after treatment) and pinch force (mean, 0.5 Newtons) in the active group, but not in the sham group. Low-frequency rTMS to the contralesional motor cortex early after stroke is feasible, safe and potentially effective to improve function of the paretic hand, in patients with mild to severe hemiparesis. These promising results will be valuable to design larger randomized clinical trials.

Exercise training restores the endothelial progenitor cells number and function in hypertension: implications for angiogenesis

Objectives: Aerobic exercise training has been established as an important nonpharmacological treatment for hypertension. We investigated whether the number and function of endothelial progenitor cells (EPCs) are restored after exercise training, potentially contributing to neovascularization in hypertension. Methods: Twelve-week-old male spontaneously hypertensive rats (SHRs, n = 14) and Wistar Kyoto (WKY, n = 14) rats were assigned to four groups: SHR; trained SHR (SHR-T); WKY; and trained WKY. Exercise training consisted of 10 weeks of swimming. EPC number and function, as well as the vascular endothelial growth factor (VEGF), nitrotyrosine and nitrite concentration in peripheral blood were quantified by fluorescence-activated cell sorter analysis (CD34+/Flk1+ cells), colony-forming unit assay, ELISA and nitric oxide (NO) analyzer, respectively. Soleus capillary/fiber ratio and protein expression of VEGF and endothelial NO synthase (eNOS) by western blot were assessed. Results: Exercise training was effective in reducing blood pressure in SHR-T accompanied by resting bradycardia, an increase in exercise tolerance, peak oxygen uptake (VO2) and citrate synthase activity. In response to hypertension, the amount of peripheral blood-EPC and number of colonies were decreased in comparison with control levels. In contrast, exercise training normalized the EPC levels and function in SHR-T accompanied by an increase in VEGF and NO levels. In addition, oxidative stress levels were normalized in SHR-T. Similar results were found in the number and function of bone marrow EPC. Exercise training repaired the peripheral capillary rarefaction in hypertension by a signaling pathway VEGF/eNOS-dependent in SHR-T. Moreover, improvement in EPC was significantly related to angiogenesis. Conclusion: Our data show that exercise training repairs the impairment of EPC in hypertension, which could be associated with peripheral revascularization, suggesting a mechanism for its potential therapeutic: application in vascular diseases.

Relationship between global structural parameters and Enzyme Commission hierarchy: Implications for function prediction

In protein databases there is a substantial number of proteins structurally determined but without function annotation. Understanding the relationship between function and structure can be useful to predict function on a large scale. We have analyzed the similarities in global physicochemical parameters for a set of enzymes which were classified according to the four Enzyme Commission (EC) hierarchical levels. Using relevance theory we introduced a distance between proteins in the space of physicochemical characteristics. This was done by minimizing a cost function of the metric tensor built to reflect the EC classification system. Using an unsupervised clustering method on a set of 1025 enzymes, we obtained no relevant clustering formation compatible with EC classification. The distance distributions between enzymes from the same EC group and from different EC groups were compared by histograms. Such analysis was also performed using sequence alignment similarity as a distance. Our results suggest that global structure parameters are not sufficient to segregate enzymes according to EC hierarchy. This indicates that features essential for function are rather local than global. Consequently, methods for predicting function based on global attributes should not obtain high accuracy in main EC classes prediction without relying on similarities between enzymes from training and validation datasets. Furthermore, these results are consistent with a substantial number of studies suggesting that function evolves fundamentally by recruitment, i.e., a same protein motif or fold can be used to perform different enzymatic functions and a few specific amino acids (AAs) are actually responsible for enzyme activity. These essential amino acids should belong to active sites and an effective method for predicting function should be able to recognize them. (C) 2012 Elsevier Ltd. All rights reserved.

Effects of a combined strengthening, stretching and functional training program versus usual-care on gait biomechanics and foot function for diabetic neuropathy: a randomized controlled trial

Background: Polyneuropathy is a complication of diabetes mellitus that has been very challenging for clinicians. It results in high public health costs and has a huge impact on patients' quality of life. Preventive interventions are still the most important approach to avoid plantar ulceration and amputation, which is the most devastating endpoint of the disease. Some therapeutic interventions improve gait quality, confidence, and quality of life; however, there is no evidence yet of an effective physical therapy treatment for recovering musculoskeletal function and foot rollover during gait that could potentially redistribute plantar pressure and reduce the risk of ulcer formation. Methods/Design: A randomised, controlled trial, with blind assessment, was designed to study the effect of a physiotherapy intervention on foot rollover during gait, range of motion, muscle strength and function of the foot and ankle, and balance confidence. The main outcome is plantar pressure during foot rollover, and the secondary outcomes are kinetic and kinematic parameters of gait, neuropathy signs and symptoms, foot and ankle range of motion and function, muscle strength, and balance confidence. The intervention is carried out for 12 weeks, twice a week, for 40-60 min each session. The follow-up period is 24 weeks from the baseline condition. Discussion: Herein, we present a more comprehensive and specific physiotherapy approach for foot and ankle function, by choosing simple tasks, focusing on recovering range of motion, strength, and functionality of the joints most impaired by diabetic polyneuropathy. In addition, this intervention aims to transfer these peripheral gains to the functional and more complex task of foot rollover during gait, in order to reduce risk of ulceration. If it shows any benefit, this protocol can be used in clinical practice and can be indicated as complementary treatment for this disease.

Lithium in M 67: From the main sequence to the red giant branch

Context. Lithium abundances in open clusters are a very effective probe of mixing processes, and their study can help us to understand the large depletion of lithium that occurs in the Sun. Owing to its age and metallicity, the open cluster M 67 is especially interesting on this respect. Many studies of lithium abundances in M 67 have been performed, but a homogeneous global analysis of lithium in stars from subsolar masses and extending to the most massive members, has yet to be accomplished for a large sample based on high-quality spectra. Aims. We test our non-standard models, which were calibrated using the Sun with observational data. Methods. We collect literature data to analyze, for the first time in a homogeneous way, the non-local thermal equilibrium lithium abundances of all observed single stars in M 67 more massive than similar to 0.9 M-circle dot. Our grid of evolutionary models is computed assuming a non-standard mixing at metallicity [Fe/H] = 0.01, using the Toulouse-Geneva evolution code. Our analysis starts from the entrance into the zero-age main-sequence. Results. Lithium in M 67 is a tight function of mass for stars more massive than the Sun, apart from a few outliers. A plateau in lithium abundances is observed for turn-off stars. Both less massive (M >= 1.10 M-circle dot) and more massive (M >= 1.28 M-circle dot) stars are more depleted than those in the plateau. There is a significant scatter in lithium abundances for any given mass M <= 1.1 M-circle dot. Conclusions. Our models qualitatively reproduce most of the features described above, although the predicted depletion of lithium is 0.45 dex smaller than observed for masses in the plateau region, i.e. between 1.1 and 1.28 solar masses. More work is clearly needed to accurately reproduce the observations. Despite hints that chromospheric activity and rotation play a role in lithium depletion, no firm conclusion can be drawn with the presently available data.

Harassment at work? Empowerment and autonomy as coping strategies of young workers

There is a considerable number of researches about workplace violence, but few relate young workers and work harassment. This study aimed to investigate the reported perceptions of young apprentices and trainees about moral harassment at work and related coping strategies. Forty adolescent workers (22 men and 18 women) between 15 and 20 years old who received training by a non-governmental organization in Sao Paulo, Brazil, participated in the study. Data collection included individual and collective interviews. It was used an in-depth semi structured interview protocol. The discourses were analyzed using the hermeneutic-dialectic frame. Results showed that young workers reported little or no knowledge of strategies to cope with moral harassment at work, showing vulnerability to the effects of aggression. Effective coping strategies at work should embrace two important concepts of health promotion: empowerment and autonomy.

Bioremediation of Herbicide Velpar K (R) In Vitro in Aqueous Solution with Application of EM-4 (Effective Microorganisms)

This work assessed the bioremediation of herbicide Velpar K (R), in vitro in aqueous solution, used against weeds in sugar cane in Sao Paulo state. The herbicide contained Hexazinone and Diuron. It was used the microbial inoculant denominated Effective Microorganisms (EM-4), pool of microorganisms from soil that contained lactic and photosynthetic bacteria, fungi, yeasts and actinomycetes for bioremediation. Results for the depth of cultivation on agar-agar inoculated with EM-4 showed the microorganisms growth in the concentrations between 0.2% and 1.0% of the Velpar K (R) in the gel. The analysis of high performance liquid chromatography ( HPLC) showed that the EM-4 was effective for the bioremediation of the herbicide, which reached the values of 80% for diuron and 70% for hexazinone after 21 days in solution of 2:1 of Velpar K (R)/EM-4 ratio. These results could be useful for planning the bioremediation of contaminated areas with Velpar K (R).

The effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder

Background. - Persistent impairment in cognitive function has been described in euthymic individuals with bipolar disorder. Collective work indicates that obesity is associated with reduced cognitive function in otherwise healthy individuals. This sub-group post-hoc analysis preliminarily explores and examines the association between overweight/obesity and cognitive function in euthymic individuals with bipolar disorder. Methods. - Euthymic adults with DSM-IV-TR-defined bipolar I or II disorder were enrolled. Subjects included in this post-hoc analysis (n = 67) were divided into two groups (normal weight, body mass index [BMI] of 18.5-24.9 kg/m(2); overweight/obese, BMI >= 25.0 kg/m(2)). Demographic and clinical information were obtained at screening. At baseline, study participants completed a comprehensive cognitive battery to assess premorbid IQ, verbal learning and memory, attention and psychomotor processing speed, executive function, general intellectual abilities, recollection and habit memory, as well as self-perceptions of cognitive failures. Results. - BMI was negatively correlated with attention and psychomotor processing speed as measured by the Digit Symbol Substitution Test (P < 0.01). Overweight and obese bipolar individuals had a significantly lower score on the Verbal Fluency Test when compared to normal weight subjects (P < 0.05). For all other measures of cognitive function, non-significant trends suggesting a negative association with BMI were observed, with the exception of measures of executive function (i.e. Trail Making Test B) and recollection memory (i.e. process-dissociation task). Conclusion. - Notwithstanding the post-hoc methodology and relatively small sample size, the results of this study suggest a possible negative effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder. Taken together, these data provide the impetus for more rigorous evaluation of the mediational role of overweight/obesity (and other medical co-morbidity) on cognitive function in psychiatric populations. (C) 2011 Elsevier Masson SAS. All rights reserved.

Atopic dermatitis: correlation between non-damaged skin barrier function and disease activity

Background Atopic dermatitis (AD) is a chronic dermatosis, predominant in childhood, characterized by pruritus and eczematous-type lesions with xerosis as the prominent clinical sign. Objectives To analyze the correlation between biophysical measurements of skin barrier function and other assessment criteria of clinical severity according to Rajka and Langelands criteria. Methods Biophysical measurements [transepidermal water loss (TEWL) and corneometry] were obtained from 120 patients with the diagnosis of AD. Serum levels of IgE were also evaluated. Results A significant correlation between corneometry, TEWL, and clinical severity of AD was found. Data showed an inverse correlation between corneometry, TEWL, and AD severity, and a significant difference (P < 0.001) between mean of corneometry and TEWL and AD severity (mild, moderate, and severe). As for IgE levels, corneometry had significant negative correlation, in contrast with TEWL, which showed a significant positive correlation (P < 0.001). Conclusion Biophysical measurements of skin barrier in non-lesional skin of AD may work as an evaluation factor for AD severity.

Parametric Analysis of Effective Material Properties of Thickness-Shear Piezoelectric Macro-Fibre Composites

A previous study on the characterization of effective material properties of a d(15) thickness-shear piezoelectric Macro-Fibre Composite (MFC) made of seven layers (Kapton, Acrylic, Electrode, Piezoceramic Fibre and Epoxy Composite, Electrode, Acrylic, Kapton) using a finite element homogenization method has shown that the packaging reduces significantly the shear stiffness of the piezoceramic material and, thus, leads to significantly smaller effective electromechanical coupling coefficient k(15) and piezoelectric stress constant e(15) when compared to the piezoceramic fibre properties. Therefore, the main objective of this work is to perform a parametric analysis in which the effect of the variations of fibre volume fraction, Epoxy elastic modulus, electrode thickness and active layer thickness on the MFC effective material properties is evaluated. Results indicate that an effective d(15) MFC should use relatively thick fibres having relatively high shear modulus and relatively stiff epoxy filler. On the other hand, the electrode thickness does not affect significantly the MFC performance.