Identification and characterization of deforestation hot spots in Venezuela using MODIS satellite images

Land cover changes over time as a result of human activity. Nowadays deforestation may be considered one of the main environmental problems. The objective of this study was to identify and characterize changes to forest cover in Venezuela between 2005-2010. Two maps of deforestation hot spots were generated on the basis of MODIS data, one using digital techniques and the other by means of direct visual interpretation by experts. These maps were validated against Landsat ETM+ images. The accuracy of the map obtained digitally was estimated by means of a confusion matrix. The overall accuracy of the maps obtained digitally was 92.5%. Expert opinions regarding the hot spots permitted the causes of deforestation to be identified. The main processes of deforestation were concentrated to the north of the Orinoco River, where 8.63% of the country's forests are located. In this region, some places registered an average annual forest change rate of between 0.72% and 2.95%, above the forest change rate for the country as a whole (0.61%). The main causes of deforestation for the period evaluated were agricultural and livestock activities (47.9%), particularly family subsistence farming and extensive farming which were carried out in 94% of the identified areas.

Nesting and neonates of the yellow-spotted river turtle (Podocnemis unifilis, Podocnemididae) in the Araguari River basin, eastern Amazon, Brazil

Predation and alteration of microhabitats may represent high risk for nesting of Amazonian turtles. This study aimed at investigating the nesting and body parameters of neonates of Podocnemis unifilis in the Araguari River basin, State of Amapá, Brazil. The spawning sites of this turtle were monitored along the Falsino River (a region with two reserves) and in the urban area of the Porto Grande city along the Araguari River, from August to December 2011. A total of 180 nests were found and the nesting occurred from September to November, with prevalence in October. Eggs hatching occurred in December. The mean incubation period was 63.5 ± 5.2 days and the eggs hatching success was 25%. However, approximately 80% of the nests had suffered predation mainly by humans, which occurred in both the protected areas of the reserves and the urban area. The pattern of nesting site choice was discussed. Egg size was larger than that previously described for the same turtle species in the other regions. The body condition index of neonates indicated a good use of vitelline reserves. The results indicate the urgent need for strategic actions to conserve and maintain the natural stocks of this relatively vulnerable turtle in the region.

Virtual reality in assessment and treatment of schizophrenia: a systematic review

Objective To conduct a systematic review about the use of virtual reality (VR) for evaluation, treatment and/or rehabilitation of patients with schizophrenia, focused on: areas, fields and objectives; methodological issues; features of the VR used; viability and efficiency of this resource. Methods Searches were performed about schizophrenia and virtual reality in PsycINFO, Academic Search Complete, MEDLINE Complete, CINAHL with Full Text, Web of Science and Business Source Premier databases, using the following keywords: [“schizophrenia”] AND [“virtual reality” OR “serious game”] AND [“treatment” OR “therapy” OR “rehabilitation”]. The search was carried out between November 2013 and June 2014 without using any search limiters. Results A total of 101 papers were identified, and after the application of exclusion criteria, 33 papers remained. The studies analysed focused on the use of VR for the evaluation of cognitive, social, perceptual and sensory skills, and the vast majority were experimental studies, with virtual reality specifically created for them. All the reviewed papers point towards a reliable and safe use of VR for evaluating and treating cognitive and social deficits in patients with schizophrenia, with different results in terms of generalisation, motivation, assertiveness and task participation rate. Some problems were highlighted, such as its high cost and a constant need for software maintenance. Conclusion The studies show that using the virtual reality may streamline traditional evaluation/rehabilitation programmes, allowing to enhance the results achieved, both in the cognitive and in the social field, helping for the legitimisation of this population’s psycho-social inclusion.

Characteristics and identification of sites of chagasic ventricular tachycardia by endocardial mapping

OBJECTIVE: To study electrophysiological characteristics that enable the identification and ablation of sites of chagasic tachycardia. METHODS: Thirty-one patients with chronic Chagas' heart disease and sustained ventricular tachycardia (SVT) underwent electrophysiological study to map and ablate that arrhythmia. Fifteen patients had hemodinamically stable SVT reproducible by programmed ventricular stimulation, 9 men and 6 women with ages ranging from 37 to 67 years and ejection fraction varying from 0.17 to 0.64. Endocardial mapping was performed during SVT in all patients. Radiofrequency (RF) current was applied to sites of presystolic activity of at least 30 ms. Entrainment was used to identify reentrant circuits. In both successful and unsuccessful sites of RF current application, electrogram and entrainment were analyzed. RESULTS: Entrainment was obtained during all mapped SVT. In 70.5% of the sites we observed concealed entrainment and ventricular tachycardia termination in the first 15 seconds of RF current application. In the unsuccessful sites, significantly earlier electrical activity was seen than in the successful ones. Concealed entrainment was significantly associated with ventricular tachycardia termination. Bystander areas were not observed. CONCLUSION: The reentrant mechanism was responsible for the genesis of all tachycardias. In 70.5% of the studied sites, the endocardial participation of the slow conducting zone of reentrant circuits was shown. Concealed entrainment was the main electrophysiological parameter associated with successful RF current application. There was no electrophysiological evidence of bystander regions in the mapped circuits of SVT.

Influence of the echocardiographic score and not of the previous surgical mitral commissurotomy on the outcome of percutaneous mitral balloon valvuloplasty

OBJECTIVE: To evaluate prior mitral surgical commissurotomy and echocardiographic score influence on the outcomes and complications of percutaneous mitral balloon valvuloplasty. METHODS: We performed 459 complete mitral valvuloplasty procedures. Four hundred thirteen were primary valvuloplasty and 46 were in patients who had undergone prior surgical commissurotomy. The prior commissurotomy group was older, had higher echo scores, and a tendency toward a higher percentage of atrial fibrillation. RESULTS: When the groups were compared with each other, no differences were found in pre- and postprocedure mean pulmonary artery pressure, mean mitral gradient, mitral valve area, and mitral regurgitation . Because we found no significant differences, we subdivided the entire group based on echo scores, those with echo scores <=8 and those with echo scores >8 the mitral valve area being higher in the <=8 echo score group 2.06±0.42 versus 1.90±0.40cm² (p=0.0090) in the >8 echo score group. CONCLUSION: Dividing the groups based on echo score revealed that the higher echo score group had smaller mitral valve areas postvalvuloplasty.

Comparison of Cardiovascular Risk Factors in Different Areas of Health Care Over a 20-Year Period

Background:Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Knowledge about cardiovascular risk factors (CVRFs) in young adults and their modification over time are measures that change the risks and prevent CVDs.Objectives:To determine the presence of CVRFs and their changes in different health care professionals over a period of 20 years.Methods:All students of medicine, nursing, nutrition, odontology, and pharmacy departments of Federal University of Goiás who agreed to participate in this study were evaluated when they started their degree courses and 20 years afterward. Questionnaires on CVRFs [systemic arterial hypertension (SAH), diabetes mellitus, dyslipidemia, and family history of early CVD, smoking, alcohol consumption, and sedentarism] were administered. Cholesterol levels, blood sugar levels, blood pressure, weight, height, and body mass index were determined. The Kolmogorov-Smirnov test was used to evaluate distribution, the chi-square test was used to compare different courses and sexes, and the McNemar test was used for comparing CVRFs. The significance level was set at a p value of < 0.05.Results:The first stage of the study included 281 individuals (91% of all the students), of which 62.9% were women; the mean age was 19.7 years. In the second stage, 215 subjects were reassessed (76% of the initial sample), of which 59.07% were women; the mean age was 39.8 years. The sample mostly consisted of medical students (with a predominance of men), followed by nursing, nutrition, and pharmacy students, with a predominance of women (p < 0.05). Excessive weight gain, SAH, and dyslipidemia were observed among physicians and dentists (p < 0.05). Excessive weight gain and SAH and a reduction in sedentarism (p < 0.05) were observed among pharmacists. Among nurses there was an increase in excessive weight and alcohol consumption (p < 0.05). Finally, nutritionists showed an increase in dyslipidemia (p < 0.05).Conclusion:In general, there was an unfavorable progression of CVRFs in the population under study, despite it having adequate specialized knowledge about these risk factors.

Temperature, urbanization and body color polymorphism in South Brazilian populations of Drosophila kikkawai (Diptera, Drosophilidae)

Body color polymorphism of urban populations of cosmopolite fly Drosophila kikkawai Burla, 1954 was investigated in relation to its possible association with environmental temperature. Samples of D. kikkawai were collected in spring, summer, autumn and winter between 1987 to 1988, in zones with different levels of urbanization in the southern Brazilian city of Porto Alegre, Rio Grande do Sul. A clear association was observed between darker flies and both seasons with low temperatures and areas of low urbanization (where temperature is generally lower than in urbanized areas). Results of preliminary laboratory experiments involving six generations of flies grown in chambers at temperatures of 17º and 25ºC confirmed this tendency to a relationship between body color and temperature, with allele frequency of the main gene involved in body pigmentation changing over time.

Species richness, relative abundance, and habitat of reproduction of terrestrial frogs in the Triângulo Mineiro region, Cerrado biome, southeastern Brazil

Based on field observations and pitfall sampling, we determined the species richness, relative abundance, and reproductive habitat of terrestrial frogs in three municipalities in the Triângulo Mineiro region, south Cerrado biome, in southeastern Brazil. We found thirty-two species of terrestrial frogs, belonging to the families Brachycephalidae, Bufonidae, Cycloramphidae, Dendrobatidae, Leiuperidae, Leptodactylidae and Microhylidae. Most of the species were found in open areas and reproduced in human-generated environments, such as artificial lakes (10 species) and ponds (14 species). Dominance was high, with Physalaemus cuvieri Fitzinger, 1826 (Leiuperidae) representing 48% of sampled frogs. A larger number of individuals was captured in the wet season, when most of the species were reproducing. Compared to other areas of Cerrado biome, the Triângulo Mineiro sites presented a larger number of species, which may be attributed to the larger sampled area and greater sampling effort, lower altitude and presence of human generated habitats. The richness of terrestrial frogs was also larger than that in some forested localities in southeastern Brazil, indicating that the number of species cannot be explained only by precipitation and type of vegetation cover. The greater abundance of individuals during the wet season may be related to a greater movement of adults to breeding sites and to juvenile recruitment/dispersion. The heterogeneity of environments in the Cerrado biome, including its several isolated highlands, contributes to its high (local and regional) diversity of frogs.

Conservation status assessment of the amphibians and reptiles of Uruguay

The native species of amphibians and reptiles of Uruguay were categorized according to the IUCN Red List criteria. Out of 47 amphibian species, seven are listed as Critically Endangered (CR), five as Endangered (EN), one as Vulnerable (VU), three as Near Threatened (NT), and two as Data Deficient (DD); the remaining species are considered to be Least Concern (LC). Among the 64 species of reptiles evaluated, one is listed as Critically Endangered (CR), seven as Endangered (EN), two as Vulnerable (VU), one as Near Threatened (NT) and seven as Data Deficient (DD); the rest are considered to be Least Concern (LC). The use of these results as an additional criterion in the definition of protected areas in Uruguay will contribute towards the conservation of the aforementioned threatened species and their associated ecosystems.

Effect of temperature on the survival and growth of freshwater prawns Macrobrachium borellii and Palaemonetes argentinus (Crustacea, Palaemonidae)

During the two-month rearing period, the effect of four water temperatures (15°C, 20°C, 25°C and 30°C) on survival rate, number of molts, and growth rate (molt increment and intermolt period) of juvenile Macrobrachium borellii Nobili, 1896 and Palaemonetes argentinus Nobili, 1901 prawns was evaluated in laboratory conditions. The two species showed some similarities in their both survival and growth pattern at different temperatures. The survival rate was highest at 20°C and 25°C, decreasing at the lowest temperature. The number of molts increased at higher temperatures, ranging the intermolt period from 22.2 days to 9.9 days, for M. borellii, and from 20.8 to 9.5 days for P. argentinus, corresponding those values to 15°C and 30°C, respectively. No difference between species was noted in the intermolt period. The size increment by molting increased significantly from 15°C to 25°C, whereas a reduction in the growth of prawns was observed at 30°C. Significant differences among temperatures were found in the slope of regressions between the size increment by molting and the cephalothorax length. M. borellii showed a significantly higher tolerance to elevated temperature and a faster growth (about twice at 25°C) than P. argentinus. These differences could provide M. borellii a competitive advantage for a better adaptation to the dynamic of freshwater environment, especially in areas with anthropogenic impact.

Abundance, breeding and food of the Little Blue Heron Egretta caerulea (Aves, Ardeidae) in the Patos Lagoon estuary, a recently colonized area in southern Brazil

We document the expansion of the breeding distribution of the Little Blue Heron Egretta caerulea (Linnaeus, 1758) to 850 km beyond its previous southern limit in South America. In addition we present data on abundance, breeding biology and food of the species in the Patos Lagoon estuary, the area which the species recently colonized. The maximum abundance recorded in the breeding colony and in a nocturnal roosting site was 53 and 49 individuals respectively. Nesting occurred from September to March. Birds nested in a mixed breeding colony together with about 3,000 breeding pairs of seven other species of Pelecaniformes, in a swampy forest near the margin of the estuary. Five nests were between 1.5 and 4.3 m from the ground, on the shrub Daphnopsis racemosa (Thymelaeaceae), on the trees Sebastiana brasiliensis (Euphorbiaceae) and Mimosa bimucronata (Leguminosae), or on the bamboo Bambusa sp. (Poaceae). Four nests produced two fledglings each, while one nest was abandoned. Of 13 grouped samples of food regurgitated by five nestlings, Pink Shrimp Farfantepenaeus paulensis (Perez-Farfante, 1967) constituted 70% in mass, while total length of ingested fishes and shrimps varied mostly between 20 and 50 mm. Estuarine prey items represented 99% of the total food mass. The recent southward expansion of the breeding range of the Little Blue Heron in South America may be a response to climate warming of the Patos Lagoon estuary. Degradation of estuaries in the southwestern Atlantic may also be forcing the birds to breed in areas outside previous geographical range.

Density estimates and conservation of Leopardus pardalis southernmost population of the Atlantic Forest

ABSTRACT Using camera traps and capture/recapture analyses we recorded the presence and abundance of cat species at Turvo State Park, in southern Brazil. Ocelot [Leopardus pardalis (Linnaeus, 1758)] population density was estimated for two areas of the park, with differing management profiles. Density estimates varied from 0.14 to 0.26 indiv. km2. Another five cat species were recorded at very low frequencies, precluding more accurate analyses. We estimate 24 to 45 ocelots occur in the reserve, which is probably too small for long-term maintenance of the population, if isolated. However, if habitat integrity and connectivity between the Park and the Green Corridor of Misiones is maintained, an estimated ocelot population of 1,680 individuals should have long-term viability.

The principal reservoir host of cutaneous leishmaniasis in the urban areas of Manaus, Central Amazon of Brazil

Twenty one opossums (Didelphis marsupialis) from disturbed primary forest in the vicinity of Manaus, and seven from an isolated island of secondary vegetation within the city of Manaus, were examined for the presence of Leishmania. Of the opossums from the primary forests, 13 (61.9%) were found to be positive for Leishmania braziliensis guyanenesis. One additional opossum was found to be positive for Le. mexicana amazonensis. A simple and economical trapping technique for opossums is presented here, and a control method in special cases is suggested.

Description of the adults and pupa of Simulium (Trichodagmia) perplexum, new species (Diptera: Simuliidae)

Simulium perplexum, new species, is described from the male, female and pupa and compared with the closely related S. guianense Wise. The distribution and biology of the new species are discussed. The confusion between S. perpelxum and S. guianense has hitherto prevented accurate identification of the primary vector of human onchocerciasis in highling, hyperendemic areas of the Amazônia focus of Brazil and southern Venezuela.

Effects of immigration on the prevalence of malaria in rural areas of the Amazon basin of Brazil

Epidemiological studies were conducted on malaria in three rural areas of the Amazon basin in the State of Rondônia: the town of Costa Marques, Forte Príncipe da Beira (Fort), and an immigrant settlement in the nearby forest. These studies were instituted to document the malaria problem and to describe the role of immigration on its distribution and prevalence. Hospital records in the town show that the number of malaria cases increased five fold from 1983 to 1987 and that the predominant malaria parasite changel from Plasmodium vivax to P. falciparum. Increased malaria followed increased immigration and colonization of the forest. A series of epidemiologic studies suggested the linkage between malaria and immigration as the prevalence of malaria was 1-2% at the Fort, a stable community, 8-9% at Costa Marques, a growing community, and 14-26% in the new settlements in the forest.