4,884 research outputs found
MIGRANTES TEMPORALES: RESIGNIFICACIÓN DE LAS NARRATIVAS
El objetivo de este texto es el análisis de las narrativas de campesinos migrantes temporales, procedentes de dos regiones de fuerte emigración en Brasil: el estado de Paraíba, (situado en el nordeste del país), y el norte de Minas Gerais (situado en la región sudeste), donde se localiza el Vale do Rio Jequitinhonha. El estado de São Paulo es el principal destino de estos campesinos migrantes a causa de los extensos cañaverales que, actualmente, cubren un área de más de cinco millones de hectáreas. Son utilizadas también las narrativas de campesinos migrantes para la ciudad de São Paulo y de Rio de Janeiro. La metodología se basa en la Historia Oral. El eje principal de las reflexiones sostiene la idea de que no hay una desaparición de las narrativas causada por las constantes migraciones, sino una resignificación de las mismas, a partir de la experiencia migratoria. Palabras clave: Trabajo, emigración, narrativas. Abstract The aim of this article is to analyse the narratives of the temporary peasant migrants from two important emigration regions in Brazil: the State of Paraiba (located in the Northeast region) and Vale of Jequitinhonha River in the North of Minas Gerais (located in the southeast region). The main destination of the peasant migrants is the sugar cane fields in the State of São Paulo, which covers over five millions of hectares of land. The narratives of peasant migrants who go to the cities of São Paulo and Rio de Janeiro are also analysed in the article. The methodology is grounded on oral history. The main idea of the analysis is that the narrative has not disappeared due to the permanent migrations, but there has been a re-interpretation of the narratives throughout the migration experience. Keywords: Job, emigration, narratives
Chromatographic Methods Applied to the Characterization of Bio-Oil from the Pyrolysis of Agro-Industrial Biomasses
Biomass conversion into solid, liquid and gaseous products by pyrolytic technology is one of the most promising alternative to convert the biomass into useful products and energy. The total characterization of the products from the pyrolysis of biomass is one of the great challenges in this field, mainly due to their molecular complexity. Pyrolysis is a process that causes degradation of biomass in a non‐oxidative atmosphere, at relatively high temperatures, producing a solid residue rich in carbon and mineral matter, gases and bio‐oil. The yield and properties of the products depend on the nature of the biomass and the type of the pyrolysis process (type of reactor, temperature, gas flow, catalyst). Due to the high molecular complexity of bio‐oil, many different technical had been developed to their complete characterization. This chapter describes the principles of the techniques and main application of chromatographic methods (GC, LC, GC × GC, LC × LC, Nano‐LC) in the analysis of bio‐oils derived from thermo‐degradation of biomasses. Especial attention is carried out to two‐dimensional techniques that represent the state of the art in terms of separation, sensibility, selectivity and velocity of data acquisition for characterization of complex organic mixtures. For proper use of bio‐oil in the chemical industry, it is essential the identification and unambiguous determination of its major constituents. Only then, it is possible to propose a recovery route of some of these components for the development of an industry dedicated to a bio‐refinery. For this, chromatographic methods, especially GC × GC/MS, are fundamental because they allow analysis with high sensitivity and accuracy in identifying each constituent of the bio‐oil
Reproductive Biology, Mating Behavior, and Vibratory Communication of the Brown-Winged Stink Bug, Edessa meditabunda
We describe different aspects of the reproductive biology, mating behavior, and vibratory communication of the pentatomid Edessa meditabunda (Fabr.). This species shows lower copulation frequency and reproductive potential with longer sexual maturation period compared to other species of pentatomids. Females with multiple mating show increased fecundity when compared with single-mated females and both increased fecundity and reduced longevity when compared with virgin females. Courtship and mating behavior and vibratory signals are typical and similar to what was observed in other species of pentatomids, except that males started the courtship. These results constitute the first paper on biology, behavior, and vibratory communication among species of
the subfamily Edessinae
High doses of zinc and copper alter neither cerebral metal levels nor acetylcholinesterase activity of suckling rats
This research investigated the in vivo (ZnCl2 27 mg/kg; CuSO4 10.2 mg/kg) and in vitro effects of zinc and copper on acetylcholinesterase activity of different cerebral areas, Zn and Cu levels in cerebrum, and body weight gain of young Wistar rats. Three-day-old rats were injected (s.c.) with 5 doses (saline, Zn, Cu or Zn+Cu) for 5 consecutive days and were killed 24 h after the last dose. In the other experiment, 7-day-old rats received only 1 dose (saline, Zn or Cu) and were killed at 1, 6 or 24 h after. For the in vitro experiments, the acetylcholinesterase activity from cerebrum of 8-day-old rats was analyzed in presence of Zn or Cu (0.01 to 1 mM). Regarding the in vivo experiments, only body weight gain was decreased by 5 simultaneous administrations of Zn and Cu. The acetylcholinesterase activity from cerebrum and cerebellum and cerebral zinc and copper contents were not altered by the treatments. In vitro, Cu 0.1 and 1 mM, but not Zn, inhibited the enzyme of both cerebrum and cerebellum. The enzymatic activity from cerebrum and cerebellum homogenate was more sensitive to Cu than the enzymatic activity from S2 and S1 fractions, respectively, since less metal was necessary to inhibit the enzyme
Phase behaviour and miscibility studies of collagen/silk fibroin macromolecular system in dilute solutions and solid state
Miscibility is an important issue in biopolymer blends for analysis of the behavior of polymer pairs through the detection of phase separation and improvement of the mechanical and physical properties of the blend. This study presents the formulation of a stable and one-phase mixture of collagen and regenerated silk fibroin (RSF), with the highest miscibility ratio between these two macromolecules, through inducing electrostatic interactions, using salt ions. For this aim, a ternary phase diagram was experimentally built for the mixtures, based on observations of phase behavior of blend solutions with various ratios. The miscibility behavior of the blend solutions in the miscible zones of the phase diagram was confirmed quantitatively by viscosimetric measurements. Assessing the effects of biopolymer mixing ratio and salt ions, before and after dialysis of blend solutions, revealed the importance of ion-specific interactions in the formation of coacervate-based materials containing collagen and RSF blends that can be used in pharmaceutical, drug delivery, and biomedical applications. Moreover, the conformational change of silk fibroin from random coil to beta sheet, in solution and in the final solid films, was detected by circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR), respectively. Scanning electron microscopy (SEM) exhibited alterations of surface morphology for the biocomposite films with different ratios. Surface contact angle measurement illustrated different hydrophobic properties for the blended film surfaces. Differential scanning calorimetry (DSC) showed that the formation of the beta sheet structure of silk fibroin enhances the thermal stability of the final blend films. Therefore, the novel method presented in this study resulted in the formation of biocomposite films whose physico-chemical properties can be tuned by silk fibroin conformational changes by applying different component mixing ratios228sem informaçãosem informaçã
Ocular and eyelid alterations observed in the medical school of Botucatu - São Paulo, Brazil
Modelo do estudo: observacional retrospectivo. Objetivo: conhecer a freqüência das alterações oculopalpebrais em pacientes atendidos na Faculdade de Medicina de Botucatu,São Paulo. Método: o estudo foi realizado através da análise de fichas de atendimento no Serviço de Plástica Ocular da Faculdade de Medicina de Botucatu, durante o período de 12 anos, avaliando-se a idade, sexo, procedência e diagnóstico principal dos pacientes atendidos. Resultados: no período estudado foram avaliados 3323 pacientes, 58,3% dos indivíduos eram procedentes da região de Botucatu; a faixa etária superior a 60 anos (41,6%) e o sexo feminino foram os prevalentes (55,7%) e as patologias com alteração da posição palpebral foram as mais comuns. Comentários: as alterações mais freqüentes foram as relacionadas com a posição das pálpebras e as lesões benignas; o conhecimento da freqüência das alterações oculopalpebrais é importante para a adoção de medidas preventivas e para planejar o treinamento de novos profissionais.Study model: observational, retrospective.Purpose :to evaluate the oculopalpebral alterations at Faculdade de Medicina de Botucatu, São Paulo State. Methods: a retrospective study in the Oculoplastic Service of the Faculdade de Medicina de Botucatu during the last 12 years was done. The age, sex, place of residence and the patients’ main diagnosis were evaluated. Results: 3323 patients were assisted. 58,3% of them lived in Botucatu area. The older than 60 years( 41.6%) and the females( 55.7%) were the prevalent group of attendance. The eyelid position alterations were the most common pathology observed. Comments: the positional eyelids disorders and the benign lesions were the manly pathologies observed The knowledge of the oculopalpebral alterations frequence is important to prevention and in order to teach new professionals who will act in this Ophthalmology area
Chemical composition, antibacterial and antioxidant activities of the essential oil from Vismia guianensis fruits
In recent decades, the essential oils of plants have drawn great interest as sources of natural products. Essential oil from the fruits of Vismia guianensis was tested for its chemical constituents and antimicrobial and antioxidant activities. Gas chromatography/mass spectrometry (GC-MS) analysis of the essential oil revealed the presence of 38 sesquiterpenoids. The major components were β-caryophyllene (25.8%), α-copaene (13.1%), and δ-cadinene (11.6%). Antimicrobial activities were measured against six species of Gram negative and seven species of Gram positive bacteria and showed antibacterial activity against the human pathogenic Gram-positive bacteria Staphylococcus lentus with minimum inhibitory concentration (MIC) values of 78 μg/ml. The antioxidant activity of the essential oil was evaluated using the beta carotene/linoleic acid assay and showed antioxidant activity.Key words: Vismia guianensis, chemical composition, antibacterial, antioxidant, fruits, essential oil
Cluster headache and intracranial aneurysm
In the present study we describe the cases of two patients with cluster-like headache related to intracranial carotid artery aneurysm. One of these patients responded to verapamil prescription with headache resolution. In both cases the surgical clipping of the aneurysm resolved the cluster pain. These findings strongly suggest a pathophysiological link between the two conditions. The authors discuss the potential pathophysiological mechanisms underlying cluster-like headache due to intracranial carotid artery aneurysm
Infliximab Induces Increase in Triglyceride Levels in Psoriatic Arthritis Patients
Objectives. To evaluate lipid profile changes after anti-TNF therapy in patients with psoriatic arthritis (PsA). Methods. Fifteen PsA patients (eight polyarticular, four oligoarticular, two axial, and one mutilating) under infliximab were included. None had dyslipoproteinemia or previous statin use. Total cholesterol (TC) and its fractions, inflammatory markers, and prednisone use were evaluated. Results. The comparisons of lipid levels between baseline and after three months (3M) of anti-TNF therapy showed that there was a significant increase in mean triglycerides (117.8 ± 49.7 versus 140.1 ± 64.1 mg/dL, P = 0.028) and VLDL-c (23.6 ± 10.5 versus 28.4 ± 13.7 mg/dL, P = 0.019) levels. In contrast, there were no differences in the mean TC (P = 0.28), LDL-c (P = 0.42), and HDL-c (P = 0.26) levels. Analysis of the frequencies of each lipid alteration at baseline and at 3M were alike (P > 0.05). Positive correlations were found between VLDL-c and CRP (r = 0.647, P = 0.009) and between triglycerides and CRP (r = 0.604, P = 0.017) levels at 3M. ESR reduction was observed after 3M (P = 0.04). Mean prednisone dose remained stable at beginning and at 3M (P = 0.37). Conclusion. This study demonstrated that anti-TNF may increase TG and VLDL-c levels in PsA patients after three months
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