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Cipo Canastero Asthenes luizae is a relict ovenbird restricted to rocky outcrops at high elevations within the campo rupestre vegetation of the Espinhaço Range in the state of Minas Gerais, south-eastern Brazil. This poorly known species is considered ‘Near Threatened’, but recent studies have suggested that it should be listed under a higher category of threat. To contribute to the knowledge of this species and its conservation assessment and related planning, we compiled all literature records of the species distribution (n = 16 locations), collected new data on its occurrence (n = 72 locations), and calculated its geographic range using four different approaches. First, we defined the sky islands where the species occurs (nine units) using the lowest elevation value recorded (1,100 m asl) as a cut-off. Second, we performed species distribution modelling (SDM) across the sky islands and identified an area of 2,225.21 km2. Third, we measured the species’ extent of occurrence (EOO = 24,555.85 km2) and used SDM to estimate its upper limit (EOOup = 30,697.58 km2). Fourth, we measured the area of occupancy (AOO = 228 km2) and used SDM to estimate its upper limit (AOOup = 1,827.39 km2). We analysed the Cipo Canastero sky islands in terms of landscape metrics including size, isolation, protected area coverage, shape index, core area index, and proportion covered by SDM. We observed a very fragmented distribution, especially in the North sector of the species distribution, composed of small and isolated populations (separated by up to 112 km); the South sector is the core of its distribution and is composed of larger, more connected patches with differences in shape complexity that are not strongly influenced by an edge effect. The range sizes calculated, along with other reported information regarding population and habitat trends, justifies the inclusion of the species in at least the ‘Vulnerable’ category.
Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.
Population growth and rising incomes have led to increasing global demand for meat products. Meeting this demand without converting remaining natural ecosystems or further degrading ecosystems is one of the largest global sustainability challenges. A critical step to overcoming this challenge is to increase the productivity of livestock grazing systems, which occupy the largest land area of any type of agriculture globally. Integrated crop−livestock systems (iCL), which re-couple crop and livestock production at the farm scale, have been considered a promising strategy to tackle this challenge by restoring degraded pasturelands and providing supplemental nutrition to livestock. However, few studies have analyzed the economic viability of such systems, especially in Brazil, an important player in global food systems. This paper presents an economic analysis of iCL in Mato Grosso, Brazil, the largest grain and beef producer in the country, which spans the ecologically diverse Amazon, Cerrado and Pantanal biomes. We compare the economic performance of an integrated soybean/corn and beef cattle system to a continuous crop (soybean/corn) system and a continuous livestock (beef cattle) production system from 2005 to 2012. We use empirical case study data to characterize a ‘typical’ farm for each production system within the study region. We find that the integrated crop−livestock system has a higher annual net present value (NPV) per hectare (ha) than continuous cropping or livestock under a range of discount rates. However, under a scenario of substantially higher crop prices, the continuous cropping outperforms iCL. While iCL is not feasible in all regions of the Amazon and Cerrado, our results indicate that in places where the biophysical and market conditions are suitable for production, it could be a highly profitable way to intensify cattle production and potentially spare land for other uses, including conservation. Nevertheless, additional credit and technical support may be needed to overcome high upfront costs and informational barriers to increase iCL areas as a sustainable development strategy for agriculture in the Amazon and Cerrado regions.
Changes in cardiac autonomic regulation, expressed by increased sympathetic activity and decreased heart rate variability, have an important relationship with the onset of lethal cardiac phenomena. Therefore, we aimed to evaluate the cardiac autonomic behaviour in young people according to their level of physical activity. Through the International Physical Activity Questionnaire, 55 healthy young non-smokers with no history of previous diseases and whose parents did not suffer from metabolic syndrome were assessed and divided into groups: sedentary (n=12), insufficiently active (n=16), active (n=14), and very active (n=13). We collected respiratory rate, systolic and diastolic blood pressure at rest, and body mass index. Subjects remained supine at rest, and without mental stress for 15 minutes in a controlled environment. Using a cardiofrequency meter (Polar® RS800CX), data were analysed in the time domain, frequency domain, and detrended fluctuation analysis. For the sedentary group, the mean RR and rMSSD were significantly lower, and the insufficiently active group showed higher means, but significantly only for rMSSD. The insufficiently active group showed in the detrended fluctuation analysis that α2 was significantly lower compared with the sedentary, active, and very active groups. We conclude that young, healthy, sedentary individuals present an increased heart rate and that insufficiently active individuals present a decreased fractal correlation and increased parasympathetic activity.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
There is no suitable vaccine against human visceral leishmaniasis (VL) and available drugs are toxic and/or present high cost. In this context, diagnostic tools should be improved for clinical management and epidemiological evaluation of disease. However, the variable sensitivity and/or specificity of the used antigens are limitations, showing the necessity to identify new molecules to be tested in a more sensitive and specific serology. In the present study, an immunoproteomics approach was performed in Leishmania infantum promastigotes and amastigotes employing sera samples from VL patients. Aiming to avoid undesired cross-reactivity in the serological assays, sera from Chagas disease patients and healthy subjects living in the endemic region of disease were also used in immunoblottings. The most reactive spots for VL samples were selected, and 29 and 21 proteins were identified in the promastigote and amastigote extracts, respectively. Two of them, endonuclease III and GTP-binding protein, were cloned, expressed, purified and tested in ELISA experiments against a large serological panel, and results showed high sensitivity and specificity values for the diagnosis of disease. In conclusion, the identified proteins could be considered in future studies as candidate antigens for the serodiagnosis of human VL.
We assessed self-reported drives for alcohol use and their impact on clinical features of alcohol use disorder (AUD) patients. Our prediction was that, in contrast to “affectively” (reward or fear) driven drinking, “habitual” drinking would be associated with worse clinical features in relation to alcohol use and higher occurrence of associated psychiatric symptoms.
Fifty-eight Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) alcohol abuse patients were assessed with a comprehensive battery of reward- and fear-based behavioral tendencies. An 18-item self-report instrument (the Habit, Reward and Fear Scale; HRFS) was employed to quantify affective (fear or reward) and non-affective (habitual) motivations for alcohol use. To characterize clinical and demographic measures associated with habit, reward, and fear, we conducted a partial least squares analysis.
Habitual alcohol use was significantly associated with the severity of alcohol dependence reflected across a range of domains and with lower number of detoxifications across multiple settings. In contrast, reward-driven alcohol use was associated with a single domain of alcohol dependence, reward-related behavioral tendencies, and lower number of detoxifications.
These results seem to be consistent with a shift from goal-directed to habit-driven alcohol use with severity and progression of addiction, complementing preclinical work and informing biological models of addiction. Both reward-related and habit-driven alcohol use were associated with lower number of detoxifications, perhaps stemming from more benign course for the reward-related and lack of treatment engagement for the habit-related alcohol abuse group. Future work should further explore the role of habit in this and other addictive disorders, and in obsessive-compulsive related disorders.
Despite recent advancements on cloud-enabled and human-in-the-loop cyber-physical systems, there is still a lack of understanding of how infrastructure-related quality of service (QoS) issues affect user-perceived quality of experience (QoE). This work presents a pilot experiment over a cloud-enabled mobility assistive device providing a guidance service and investigates the relationship between QoS and QoE in such a system. In our pilot experiment, we employed the CloudWalker, a system linking smart walkers and cloud platforms, to physically interact with users. Different QoS conditions were emulated to represent an architecture in which control algorithms are performed remotely. Results point out that users report satisfactory interaction with the system even under unfavorable QoS conditions. We also found statistically significant data linking QoE degradation to poor QoS conditions. We finalize discussing the interplay between QoS requirements, the human-in-the-loop effect, and the perceived QoE in healthcare applications.
Protein is the most costly nutrient in fish feed, and while diets offered in the early stages of development typically have high levels of CP, they do not always correspond to the real requirements of the animals. Thus, research that seeks to learn the true nutritional requirements of fish is fundamental to improving commercial fish culture. The present study evaluated the protein requirements of Nile tilapia (Oreochromis niloticus) under larviculture. Fish performance, gene expression for digestive enzymes and their enzymatic activity and stress response to air exposure were analyzed. Four experimental diets differing in CP level were formulated: 30%, 36%, 42% and 48%. Fish larvae were fed the experimental diets during development and sampled 10, 20 and 30 days after the beginning of the experiment for performance, gene expression and enzymatic activity. At sampling time 30, stress resistance was also evaluated by means of an air exposure test. At sampling time 10, CP levels between 36% and 48% could be used for a better performance. During this period, pepsinogen expression was greater for 30% CP, intermediate for 42% and lower for 36% and 48%. After this initial period, diets of between 30% and 42% CP are recommended for better performance. At sampling time 20, gene expression for digestive enzymes and their enzymatic activity were similar for all diets tested. At sampling time 30, the diet of 42% CP induced both greater pepsinogen expression and pepsin activity. Survival after the air exposure test after 30 days of feeding was influenced by CP level in the diet, with the highest survival being for fish fed with 36% CP. Taken together, the present results demonstrate that dietary CP influences digestive enzyme gene expression and activity, and suggest that the best CP levels for Nile tilapia larviculture vary depending on larval stage.
In the current study, phage-exposed mimotopes as targets against tegumentary leishmaniasis (TL) were selected by means of bio-panning cycles employing sera of TL patients and healthy subjects, besides the immune stimulation of peripheral blood mononuclear cells (PBMCs) collected from untreated and treated TL patients and healthy subjects. The clones were evaluated regarding their specific interferon-γ (IFN-γ) and interleukin-4 (IL-4) production in the in vitro cultures, and selectivity and specificity values were calculated, and those presenting the best results were selected for the in vivo experiments. Two clones, namely A4 and A8, were identified and used in immunization protocols from BALB/c mice to protect against Leishmania amazonensis infection. Results showed a polarized Th1 response generated after vaccination, being based on significantly higher levels of IFN-γ, IL-2, IL-12, tumour necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF); which were associated with lower production of specific IL-4, IL-10 and immunoglobulin G1 (IgG1) antibodies. Vaccinated mice presented significant reductions in the parasite load in the infected tissue and distinct organs, when compared with controls. In conclusion, we presented a strategy to identify new mimotopes able to induce Th1 response in PBMCs from TL patients and healthy subjects, and that were successfully used to protect against L. amazonensis infection.
Chikungunya virus (CHIKV) is an arbovirus transmitted by Aedes mosquitoes that was first identified in Brazil in 2014. It causes a febrile illness characterised by severe arthralgia and rash. Our group investigated a suspected CHIKV outbreak in Governador Valadares, state of Minas Gerais, Brazil and from 25 acute-phase patients, 10 had qRT-PCR positive sera samples and had E1 partial sequence amplified and Sanger sequenced. Samples were identified as East/Central/South African (ECSA) genotype by phylogenetic analysis and clustered with CHIKV sequences isolated in the neighbour state of Bahia. Our findings confirm previous predictions that ECSA genotype would spread through northeast and southeast of Brazil.
Tropical montane cloud forests (TMCFs) are characterised principally by frequent immersion in ground-level clouds, which influences their structure. This study aimed to characterise TMCFs in Serra do Papagaio State Park, Minas Gerais State, Southeast Brazil, and to test the hypothesis that TMCF areas can be highly heterogeneous by comparing the tree species composition and structural parameters of 10 TMCF patches in the studied landscape. TMCFs of Serra do Papagaio State Park are of particular interest for conservation, because they contain important populations of threatened tree species.
This study evaluated the effects of diet containing taro flour on hormone levels and the seminiferous tubules morphology of rats. After weaning, the male rats were divided into two groups (n=12 each): control group (CG) treated with control diet and taro group (TG), fed with 25% taro flour for 90 days. Food, caloric intake, mass and body length were evaluated at experiment end. Testis followed the standard histological processing. Immunostaining was performed using an anti-vimentin antibody to identify Sertoli cells. In histomorphometry, total diameter, total area, epithelial height, luminal height and luminal area were analyzed. The testosterone levels were performed using the radioimmunoassay method. Group TG presented (P<0.05): increase in mass, body length, testicular weight, histomorphometric parameters and hormonal levels. Food intake, calorie and Sertoli cells not presented statistical differences. The taro promoted increase in the testicles parameters and hormones.
In this study, a Leishmania hypothetical protein, LiHyS, was evaluated regarding its antigenicity, immunogenicity and protective efficacy against visceral leishmaniasis (VL). Regarding antigenicity, immunoblottings and an enzyme-linked immunosorbent assay using human and canine sera showed high sensitivity and specificity values for the recombinant protein (rLiHyS) in the diagnosis of VL. When evaluating the immunogenicity of LiHyS, which is possibly located in the parasite's flagellar pocket, proliferative assays using peripheral blood mononuclear cells from healthy subjects or VL patients showed a high proliferative index in both individuals, when compared to the results obtained using rA2 or unstimulated cultures. Later, rLiHyS/saponin was inoculated in BALB/c mice, which were then challenged with Leishmania infantum promastigotes. The vaccine induced an interferon-γ, interleukin (IL)-12 and granulocyte-macrophage colony-stimulating factor production, which was maintained after infection and which was associated with high nitrite and IgG2a antibody levels, as well as low IL-4 and IL-10 production. Significant reductions in the parasite load in liver, spleen, bone marrow and draining lymph nodes were found in these animals. In this context, the present study shows that the rLiHyS has the capacity to be evaluated as a diagnostic marker or vaccine candidate against VL.
Anthropogenic disturbance often results in the proliferation of native species of particular groups that leads to biotic homogenization. Leaf-cutting ants are an example of such winner organisms in tropical rain forests, but their response to disturbance in dry forests is poorly known. We investigated Atta colony density in areas of tropical dry forest in Brazil with different distance to roads and vegetation cover. Atta colonies were surveyed in 59 belt transects of 300 × 20 m, covering a total area of 35.4 ha. We found 224 Atta colonies, 131 of which were active and belonged to Atta opaciceps (87 colonies, 2.45 ha−1), A. sexdens (35 colonies, 0.98 ha−1) and A. laevigata (9 colonies, 0.25 ha−1). The density of active colonies sharply decreased from 15 ± 2.92 ha−1 in the 50-m zone along roads to only 2.55 ± 1.65 ha−1 at distances up to 300 m. The reverse pattern was observed for inactive colonies. Active Atta colonies preferentially occur in areas with low vegetation cover, while inactive colonies prefer areas with high vegetation cover. We demonstrate for the first time that anthropogenic disturbances promote the proliferation of leaf-cutting ants in dry forest in Brazil, which may affect plant regeneration via herbivory and ecosystem engineering as demonstrated for rain forests.
Lychnophora ericoides Mart. (Asteraceae), popularly known as arnica, is a plant species subjected to non-timber forest products extraction. Evidence is mounting that some local populations are on the brink of extinction. However, demographic studies of Lychnophora ericoides are rare. Therefore, as a step towards conservation, a remnant population of Lychnophora ericoides located in an area of the Cerrado (Brazilian Savanna) in Central Brazil was evaluated from 2010 through 2014. Disturbances such as wildfires and harvesting of Lychnophora ericoides were randomly distributed throughout the study period in this area. Four annual transition matrices (A1, A2, A3 and A4) were constructed, based on life stages. The main results of studies of population dynamics for this species are as follows: 1) population growth rates (λ) with 95% confidence intervals indicated a declining population in all periods from 2010 to 2014; 2) stochastic population growth rate considering the four matrices was < 1 with value λ = 0.358 and CI95% = (0.354–0.362); 3) survival with permanence at the same stage of reproductive adult individuals (46–80%) contributed most to population growth rate, based on elasticity analysis; 4) the population is much less likely to have increases in density, compared with reduction, for all intervals from 2010 to 2014, based on transient indices; 5) the low value of λ in the high-mortality year was caused by lower stasis of individuals in the seedling or sapling and juvenile life stages, as well as fecundity in the 2011–2012 and 2012–2013 intervals, as shown by a life table response experiment; and 6) 100% of the population will probably be extinct within 15 years. There is evidence that the main cause for local extinction of Lychnophora ericoides could be the effects of frequent wildfires. Based on these results, it is suggested that the time has come for significant conservation efforts to rescue this population, including monitoring, protection and education as the first steps towards protection of this vulnerable plant species.
The thermomechanical processing of NiTi shape memory alloys usually involves several steps of hot and/or cold deformation. The present work presents the structural characterization of a Ni-rich NiTi alloy bar, produced by vacuum-induced melting and thermomechanical processing in laboratory scale, aiming at massive production in the future. This study focused on the first step of hot working at 800 °C during rotary forging. Microstructural characterization was performed using differential scanning calorimetry, high- and low-temperature X-ray diffraction (XRD) using a laboratory source and synchrotron XRD. Thus, it was possible to obtain the phase transformation characteristics of the material: the transformation temperatures and the transformation sequence. Proposed thermomechanical processing is intended for production of bars and wires that will be subsequently drawn to get thin wires, for different applications, including orthodontic arch wires.
Feline leishmaniasis has been reported in various parts of the world in recent years, occurring mainly in areas where zoonotic visceral leishmaniasis (VL) is endemic. The purpose of this study was to assess the occurrence of natural infection by Leishmania spp. in domestic cats (Felis catus) in the municipality of Teresina, Piauí state, Brazil, an endemic area of VL in Brazil. The prevalence of infection by Leishmania spp. in the population under study was 4% (3/83) in the enzyme-linked immunosorbent assay (ELISA) and 4% (3/83) by smear observation and isolation in a culture medium, using popliteal lymphnode sample. Only one of the three infected cats was positive for ELISA, also being positive for feline immunodeficiency virus. In the haematologic parameters, normocytic normochromic anaemia was the most common change, being present in the three infected animals. In the biochemical measurements also were observed alterations in infected animals. The Leishmania spp. strains isolated from the culture medium were characterized as L. infantum. The presence of L. infantum infection in cats in the city of Teresina, an area endemic for VL, suggests the possible involvement of these animals in the epidemiological chain of L. infantum in high-transmission areas.
In the frame of the COST ACTION ‘EMBOS’ (Development and implementation of a pan-European Marine Biodiversity Observatory System), coverage of intertidal macroalgae was estimated at a range of marine stations along the European coastline (Subarctic, Baltic, Atlantic, Mediterranean). Based on these data, we tested whether patterns in macroalgal diversity and distribution along European intertidal rocky shores could be explained by a set of meteo-oceanographic variables. The variables considered were salinity, sea surface temperature, photosynthetically active radiation, significant wave height and tidal range and were compiled from three different sources: remote sensing, reanalysis technique and in situ measurement. These variables were parameterized to represent average conditions (mean values), variability (standard deviation) and extreme events (minimum and maximum values). The results obtained in this study contribute to reinforce the EMBOS network approach and highlight the necessity of considering meteo-oceanographic variables in long-term assessments. The broad spatial distribution of pilot sites has allowed identification of latitudinal and longitudinal gradients manifested through species composition, diversity and dominance structure of intertidal macroalgae. These patterns follow a latitudinal gradient mainly explained by sea surface temperature, but also by photosynthetically active radiation, salinity and tidal range. Additionally, a longitudinal gradient was also detected and could be linked to wave height.
The Serra Negra belongs to the Mantiqueira mountain complex, Minas Gerais, Brazil. It has a vegetation mosaic dominated by ombrophilous and seasonal forest and grassland formations. Woody physiognomies occur on patches of quartzite soils. The aim of the present study was to investigate the patterns of structure and diversity of woody vegetation on quartzite soils in Serra Negra. Ten plots (20 × 50 m) were randomly placed in patches of woody vegetation on quartzite soils along the landscape. The diameter and height of all woody plants with a diameter of ≥ 3 cm at 30 cm from the soil were measured. The 1899 individuals sampled represented 30 plant families and 68 species. A strong ecological dominance was found, with about 30% of individuals belonging to a single species, Eremanthus incanus (Asteraceae). The Shannon diversity index (H′) was 2.74 nats/individual and evenness (J) 0.65. The two most abundant and ecologically important species in this vegetation type, Eremanthus incanus and Eremanthus erythropappus, called ‘candeias’, are exploited in the region, mainly for firewood. This exploitation, combined with other factors (e.g. increased tourism), can pose risks to the conservation of the whole flora of the region.