25 resultados para híbridos intra-específicos
Resumo:
The utilization of synthetic fibers for plastic reinforcement is more and more frequent and this growing interest requires that their mechanic behavior under the most variable conditions of structural applications be known. The use of such materials in the open and exposed to the elements is one of them. In this case, it becomes extremely necessary to study their mechanical properties (strength, stiffness) and the mechanism of fracture by which the environment aging them out. In order to do that, the material must be submitted to hot steam and ultraviolet radiation exposure cycles, according to periods of time determined by the norms. This study proposal deals with the investigation of accelerated environmental aging in two laminated polymeric composites reinforced by hybrid woven made up of synthetic fibers. The configurations of the laminated composites are defined as: one laminate reinforced with hybrid woven of glass fibers/E and Kevlar fibers/49 (LHVK) and the other laminate is reinforced with hybrid tissue of glass fibers/E and of carbon fibers AS4 (LHVC). The woven are plane and bidirectional. Both laminates are impregnated with a thermofix resin called Derakane 470-300 Epoxy Vinyl-Ester and they form a total of four layers. The laminates were industrially manufactured and were made through the process of hand-lay-up. Comparative analyses were carried out between their mechanical properties by submitting specimen to uniaxial loading tractions and three-point flexion. The specimen were tested both from their original state, that is, without being environmentally aging out, and after environmental aging. This last state was reached by using the environmental aging chamber
Resumo:
This study presents the results of a survey conducted in the area of English for Specific Purposes (ESP) in order to identify (1) the learning needs of students in a course in Tourism, their desires and lacks, at a federal university, with respect to use of English; (2) the needs of the present situation of teachers and the coordinator of that course as to the language; (3) the needs of the target situation of professionals (graduates) and companies with respect to this language. This research is a case study (STAKE, 1998; YIN, 2009) and was used for data collection, instruments such as questionnaires, semi-structured interviews, and document on the Tourism Course. To this end, it was adopted the theoretical basis for the constructs of English for Specific Purposes (ESP) Inglês para Fins Específicos (IFE) in Brazil, also known as Inglês Instrumental, whose foundation is based on the work by Hutchinson and Waters (1987), Robinson (1991), Dudley-Evans and St. John (1998), Celani, Deyes, Holmes, Scott (2006), among others, since this work is devoted to a specific area, Tourism. Results show that students opined the ability to prioritize reading and speaking into the classroom. Professionals reported that the latter is an indispensable tool for entering the labor market, yet they feel unprepared and need to attend English language courses in private language schools. The testimony of company executives also point to this deficiency. Finally, the present situation of teachers reveals that, while advocating the use of English in the classroom, this is not because students prefer their mother tongue. There is also an evident lack of needs analysis. Eventually, the coordinator said that there is some uncertainty as to the methodology, content and language skills worked, and the lack of interaction among teachers of English. It was concluded, therefore, it is important to conduct a needs analysis so that one can redesign a course that meets the different contextual needs: students, teachers, coordination, represented by the institutional needs, and the labor market
Resumo:
This research has as its theoretical and methodological assumptions (1) the Narrative Inquiry (CLANDININ; CONNELLY, 2011), (2) the Systemic Functional Grammar (HALLIDAY, 1985, 1994; THOMPSON, 2002; EGGINS, 1994; HALLIDAY; MATTHIESSEN, 2004) and (3) the English for Specific Purposes Approach (ESP - HUTCHINSON; WATERS, 1987; CELANI, 2005; RAMOS, 2005), and its overall objective is to survey the meanings construed by the participants who are ESP practitioners and have not received a specific education to teach this approach at their undergraduation. The field texts and therefore the analises were divided into two distinct groups: the first with data generated from a questionnaire applied to nine professors from a federal university in the northeast of Brazil, which contains open and closed questions about their training and their experiences in teaching ESP; the second group, focusing this time on the experiences of three professors from the first group who were still teaching ESP, with data generated from interviews with these participants in addition to the data generated from their autobiographies and from the researcher´s as well. The computational tool WordSmith Tools 6.0 (SCOTT, 2012) was used to select, organize, and quantify data to be analyzed in the first group of texts, identifying the types of Processes and Participants through the Transitivity System (HALLIDAY; MATTHIESSEN, 2004). The Processes which were more used by the professors in the questionnaire were the Material, followed by the Relational and then the Mental ones, indicating that most professors reported their actions related to the teaching of ESP, rated or evaluated the approach, their training to teach it and their experiences, hence, rarely showing their thoughts and emotions about teaching ESP. Most of the nine professors say they carry out needs analysis, but not all do it according to the authors cited by them or the ones that are considered a reference in this area, such as the ones used in this research as reference. Similarly, their definitions and conceptions of ESP, in most cases, differed from these authors. All the professors claim not having had specific education to teach ESP at the undergraduation. When examining the stories of the four teachers, in the second group of the field texts, based on meaning composition according to Ely, Vinz, Downing and Anzul (2001), it was revealed that the kind of knowledge they report using when they teach ESP is related to their Personal Practical Knowledge and their Professional Knowledge (ELBAZ, 1983; CLANDININ, 1988). In their autobiographies, metaphors were also identified and they represent their concepts of teaching and being a teacher. Through this research, we hope to contribute to the understanding of what teaching ESP might mean for professors in the researched context and also to the continuing education of ESP practitioners, as well as to a review of the curricula in the English language undergraduate courses and of the role of ESP in the training of these professionals
Resumo:
The objective was measured by surface electromyography (EMGs), the activity of inspiratory muscles during incremental test in subjects with hemiparesis and show its correlation with the Functional Independence Measure (FIM). Were included in the study 32 individuals hemiparetics and 14 healthy as control group. We performed an evaluation of lung function and anthropometric data. The EMGs were performed during the incremental test with Threshold ® (15, 30, 45 and 60% of MIP) and during maximal inspiratory pressure (MIP). The electromyographic findings were calculated by the signal amplitude (RMS). All data were initially analyzed by Kolmogorov-Smirnov, the anthropometric characteristics of both groups were tested with the Levene and then intra-subject analysis (hemiparetic hemithorax and healthy hemithorax) and inter-group analysis (experimental group and control group) by paired and non-paired Student t tests and Pearson correlation. In intra-subject comparison was observed less activation (p <0.01) of the sternocleidomastoid muscle, scalene and diaphragm paretic side in both sexes - for the Threshold ® incremental test (15, 30, 45 and 60% of the MIP) and during maximal inspiratory pressure (MIP). In inter-group comparison, there was reduced activity in the diaphragm and the scalene, in hemiparetics males and females, respectivelly, during the same test. Our results demonstrate the existence of reduced electromyographic activity of inspiratory muscles in hemiparetics, including changes between different genders and suggests the need of further studies to assess the effects of specific training of inspiratory muscles.
Resumo:
Hybrids among transgenic plants and related species are expected to occur if they are sympatric and when there are not crossing barriers; as is the case, in Brazil, of cry1Ac transgenic cotton and Gossypium barbadense. This species has been maintained as dooryard plants, and should be preserved as a genetic resource. Hybrids were evaluated about traits related to fitness, leading to infer about its chances of survivor and selection. A barbadense genotype collected at the state of Mato Grosso was outcrossed to the variety DP 404, containing the gene cry1Ac, and to the isoline DP 404. All the F1 individuals and 122 among 170 F2 individuals expressed the toxin, and presented levels of resistance to pink bollworm (Pectinophora gossypiella) and cotton leafworm (Alabama argillacea) equivalent to the transgenic parent and superior to the isoline, barbadense or non transgenic hybrids. The percentage of germination and number of days to germinate did not differ among genotypes. Anthesis of the first flower and opening of the first cotton boll occurred earlier for herbaceous cotton and F1 hybrids than F2 population in average; all the populations presented a number of days to flower and opening of the first boll smaller then barbadense. The highest plants were barbadenses, and herbaceus the smallest, with F1 and F2 populations presenting intermediary heights. The number of seeds per plants were superior for F1 hybrids an herbaceous cotton, F2 populations were in average intermediary; the barbadense genotype produced the smallest number of seeds per plant. Pink bollworm, mainly, and also cotton leafworm, are important barbadense pests, so the transgene positive effect could favor the selection of hybrids, and hence G. hirsutum genome, against the maintenance of pure G. barbadense genome. The selection may be influenced by the plant uses: the smaller size of hybrids when compared to the barbadense may lead them to be differentiated from these parents to which medicinal properties are attributed; on the other hand, the greater boll production may favor hybrids maintenance with the purpose of producing lamp wicks, or use as an ornamental or swab
Resumo:
Epilepsies are neurological disorders characterized by recurrent and spontaneous seizures due to an abnormal electric activity in a brain network. The mesial temporal lobe epilepsy (MTLE) is the most prevalent type of epilepsy in adulthood, and it occurs frequently in association with hippocampal sclerosis. Unfortunately, not all patients benefit from pharmacological treatment (drug-resistant patients), and therefore become candidates for surgery, a procedure of high complexity and cost. Nowadays, the most common surgery is the anterior temporal lobectomy with selective amygdalohippocampectomy, a procedure standardized by anatomical markers. However, part of patients still present seizure after the procedure. Then, to increase the efficiency of this kind of procedure, it is fundamental to know the epileptic human brain in order to create new tools for auxiliary an individualized surgery procedure. The aim of this work was to identify and quantify the occurrence of epilepticform activity -such as interictal spikes (IS) and high frequency oscillations (HFO) - in electrocorticographic (ECoG) signals acutely recorded during the surgery procedure in drug-resistant patients with MTLE. The ECoG recording (32 channels at sample rate of 1 kHz) was performed in the surface of temporal lobe in three moments: without any cortical resection, after anterior temporal lobectomy and after amygdalohippocampectomy (mean duration of each record: 10 min; N = 17 patients; ethic approval #1038/03 in Research Ethic Committee of Federal University of São Paulo). The occurrence of IS and HFO was quantified automatically by MATLAB routines and validated manually. The events rate (number of events/channels) in each recording time was correlated with seizure control outcome. In 8 hours and 40 minutes of record, we identified 36,858 IS and 1.756 HFO. We observed that seizure-free outcome patients had more HFO rate before the resection than non-seizure free, however do not differentiate in relation of frequency, morphology and distribution of IS. The HFO rate in the first record was better than IS rate on prediction of seizure-free patients (IS: AUC = 57%, Sens = 70%, Spec = 71% vs HFO: AUC = 77%, Sens = 100%, Spec = 70%). We observed the same for the difference of the rate of pre and post-resection (IS: AUC = 54%, Sens = 60%, Spec = 71%; vs HFO: AUC = 84%, Sens = 100%, Spec = 80%). In this case, the algorithm identifies all seizure-free patients (N = 7) with two false positives. To conclude, we observed that the IS and HFO can be found in intra-operative ECoG record, despite the anesthesia and the short time of record. The possibility to classify the patients before any cortical resection suggest that ECoG can be important to decide the use of adjuvant pharmacological treatment or to change for tailored resection procedure. The mechanism responsible for this effect is still unknown, thus more studies are necessary to clarify the processes related to it
Resumo:
The principal zeitgeber for most of species is the light-dark photocycle (LD), though other environment factors as food availability, temperature and social cues may act. Daily adjustment of the circadian pacemaker may result from integration of environmental photic and non-photic cues with homeostatic cues. Characterization of non-photic effects on circadian timing system in diurnal mammals is scarce in relation to nocturnal, especially for ecologically significant cues. Thus, we analyzed the effect of conspecific vocalizations and darkness on circadian activity rhythm (CAR) in the diurnal primate Callithirx jacchus. With this objective 7 male adults were isolated in a room with controlled illumination, temperature (26,8 ± 0,2°C) and humidity (81,6 ± 3,6%), and partial acoustic isolation. Initially they were under LD 12:12 (~300:2 lux), and subsequently under constant illumination (~2 lux). Two pulses of conspecific vocalizations were applied in total darkness, separated by 22 days, at 7:30 h (external time) during 1 h. They induced phase delays at circadian times (CTs) 1 and 10 and predominantly phase advances at CTs 9 and 15. After that, two dark pulses were applied, separated by 14 days, during 1 h at 7:30 h (external time). These pulses induced phase delays at CTs 2, 3 and 18, predominantly phase advances at CTs 8, 10 and 19, and no change at CT 14. However, marmosets CAR showed oscillations in endogenous period and active phase duration influenced by vocalizations from animals outside the experimental room, which interfered on the phase responses to pulses. Furthermore, social masking and relative coordination with colony were observed. Therefore, phase responses obtained in this work cannot be attributed only to pulses. Afterwards, pulses of conspecific vocalizations were applied in total darkness at 19:00 h (external time), during 1 h for 5 consecutive days, and after 21 days, for 30 consecutive days, on attempt to synchronize the CAR. No animal was synchronized by these daily pulses, although oscillations in endogenous period were observed for all. This result may be due to habituation. Other possibility is the absence of social significance of the vocalizations for the animals due to random reproduction, since each vocalization has a function that could be lost by a mixture of sounds. In conclusion, conspecific vocalizations induce social masking and relative coordination in marmosets CAR, acting as weak zeitgeber
Resumo:
A catalyst of great interest to the scientific community tries to unite the structure of ordered pore diameter from mesoporous materials with the properties of stability and acid activity to microporous zeolites. Thus a large number of materials was developed in the past decades, which although being reported as zeolites intrinsically they fail to comply with some relevant characteristics to zeolites, and recently were named zeolitic materials of high accessibility. Among the various synthesis strategies employed, the present research approaches the synthesis methods of crystallization of silanized protozeolitic units and the method of protozeolitic units molded around surfactant micelles, in order for get materials defined as hierarchical zeolites and micro-mesoporous hybrid materials, respectively. As goal BEA/MCM-41 hybrid catalysts with bimodal pore structure formed by nuclei of zeolite Beta and cationic surfactant cetyltrimethylammonium were developed. As also was successfully synthesized the hierarchical Beta zeolite having a secondary porosity, in addition to the typical and uniform zeolite micropores. Both catalysts were applied in reactions of catalytic cracking of high density polyethylene (HDPE), to evaluate its properties in catalytic activity, aiming at the recycling of waste plastics to obtain high value-added raw materials and fuels. The BEA/MCM-41 hybrid materials with 0 days of pre-crystallization did not show enough properties for use in catalytic cracking reactions, but they showed superior catalytic properties compared to those ordered mesoporous materials of Al-MCM-41 type. The structure of Beta zeolite with hierarchical porosity leads the accessibility of HDPE bulky molecules to active centers, due to high external area. And provides higher conversion to hydrocarbons in the gasoline range, especially olefins which have great interest in the petrochemical industry
Resumo:
This study sprang from the hypothesis that spatial variations in the morbidity rate for dengue fever within the municipality of Natal are related to intra-city socioeconomic and environmental variations. The objective of the project was to classify the different suburbs of Natal according to their living conditions and establish if there was any correlation between this classification and the incidence rate for dengue fever, with the aim of enabling public health planners to better control this disease. Data on population density, access to safe drinking water, rubbish collection, sewage disposal facilities, income level, education and the incidence of dengue fever during the years 2001 and 2003 was drawn from the Brazilian Demographic Census 2000 and from the Reportable Disease Notification System -SINAN. The study is presented here in the form of two papers, corresponding to the types of analysis performed: a classification of the urban districts into quartiles according to the living conditions which exist there, in the first article; and the incidence of dengue fever in each of these quartiles, in the second. By applying factorial analysis to the chosen socioeconomic and environmental indicators for the year 2000, a compound index of living condition (ICV) was obtained. On the basis of this index, it was possible to classify the urban districts into quartiles. On undertaking this grouping (paper 1), a heterogeneous distribution of living conditions was found across the city. As to the incidence rate for dengue fever (paper 2), it was discovered that the quartile identified as having the best living conditions presented incidence rates of 15.62 and 15.24 per 1000 inhabitants respectively in the years 2001 and 2003; whereas the quartile representing worst living conditions showed incidence rates of 25.10 and 10.32 for the comparable periods. The results suggest that dengue fever occurs in all social classes, and that its incidence is not related in any evident way to the chosen formula for living conditions
Resumo:
This dissertation is about low-income rental housing vilas in the South Zone in the city of Natal. Vilas are a string of houses, built privately in an urban plot of land, usually a backyard, facing a narrow street beco. This type of housing is originated in the 19th century in the Brazilian scenario. In Natal, this has become more popular since the late 1960s. This study is aimed at analyzing the urban integration of the vilas, considering that these house a low income population, vis à vis the speedy development of Natal s most economically dynamic area. The study starts with a discussion of the production of space, taking into consideration categories such as use value, exchange value, commodity and land rent. Field work was undertaken through structured interviews with dwellers of vilas in Nova Descoberta and Ponta Negra neighbourhoods. Owners of vilas were also interviewed. Data collected indicated worrisome housing conditions. Vilas, in the areas researched, are increasingly becoming unwelcome, constituting guetos in a place where landscape is changing rapidly. Gentrification is fast under way, first because of rise in rent and taxes; second because of general rise in living costs