Impairment of electrical activation of wrist flexor and extensor muscles during gripping and functional activities in the early stage of hand osteoarthritis: A cross-sectional study.

STUDY DESIGN: This is a cross-sectional study. INTRODUCTION: The wrist extensor muscles have a fundamental role in the stabilization of the wrist while performing manual activities. However, it is unknown if the clinical signs of hand osteoarthritis (HOA) cause impairment in the activation of these muscles PURPOSE OF THE STUDY: The purpose of this study was to investigate whether early-stage HOA affects the magnitude of activation and coactivation between the wrist extensor and flexor muscles METHODS: Thirty-two subjects were divided into two groups: control group (n = 16; 55 ± 7.42 years) and a group with HOA grades 2 or 3 (HOAG; n = 16; 57 ± 7.82 years). Muscle activation was measured in m. flexor digitorum superficialis, m. flexor carpi ulnaris (FCU) and extensors (EXT) during the evaluation of grip strength and three manual activities (write, cut a paper with scissors, and close and open a bottle). The coactivation index was calculated between the electromyography of the flexors (FCU and FSD) and wrist EXT. RESULTS: HOAG presented reduced muscle activation in all tasks, with a statistical difference for the flexor digitorum superficialis and EXT in the scissors activity, and for the FCU in the bottle activity. No differences were found between groups for the coactivation index and grip strength. DISCUSSION: The reduced muscle activity may be due to an inability of the patients of the HOAG to recruit all motor units or to an inhibition related to the presence of pain. CONCLUSION: In the early stages of HOA, there is a functional deficit associated with a reduced muscle activity of the wrist muscles during manual activities.

Selecting and improving activated homogeneous catalytic processes for pollutant removal. Kinetics, mineralization and optimization.

The degradation of a model pollutant, tartrazine, very used in food industry and usually present in WWTPs effluents and surface waters, was investigated by nine activated homogeneous catalytic processes, namely, Fe3+/H2O2, Fe2+/H2O2, UV/H2O2, UV/S2O82-, UV/Fe2+/H2O2, UV/Fe3+/H2O2, UV, VIS/Fe3+/H2O2, and VIS/Fe3+/H2O2/C2O42-. In order to compare the mineralization and oxidation ability of each process, the removal of dye, chemical oxygen demand (COD) and total organic carbon (TOC) were analyzed, as well as the overall kinetic rate constant. Also, the different oxidation path-ways (direct photolysis and/or oxidation by free radicals) were estimated for each system. After the comparison, the Fenton process, which had the highest mineralization values, was tested in luminous and dark phases using designed experiments, and the influences of all operating variables were studied by RSM.

Effect of Flexible Family Visitation on Delirium Among Patients in the Intensive Care Unit: The ICU Visits Randomized Clinical Trial.

Importance: The effects of intensive care unit (ICU) visiting hours remain uncertain. Objective: To determine whether a flexible family visitation policy in the ICU reduces the incidence of delirium. Design, Setting and Participants: Cluster-crossover randomized clinical trial involving patients, family members, and clinicians from 36 adult ICUs with restricted visiting hours (<4.5 hours per day) in Brazil. Participants were recruited from April 2017 to June 2018, with follow-up until July 2018. Interventions: Flexible visitation (up to 12 hours per day) supported by family education (n = 837 patients, 652 family members, and 435 clinicians) or usual restricted visitation (median, 1.5 hours per day; n = 848 patients, 643 family members, and 391 clinicians). Nineteen ICUs started with flexible visitation, and 17 started with restricted visitation. Main Outcomes and Measures: Primary outcome was incidence of delirium during ICU stay, assessed using the CAM-ICU. Secondary outcomes included ICU-acquired infections for patients; symptoms of anxiety and depression assessed using the HADS (range, 0 [best] to 21 [worst]) for family members; and burnout for ICU staff (Maslach Burnout Inventory). Results: Among 1685 patients, 1295 family members, and 826 clinicians enrolled, 1685 patients (100%) (mean age, 58.5 years; 47.2% women), 1060 family members (81.8%) (mean age, 45.2 years; 70.3% women), and 737 clinicians (89.2%) (mean age, 35.5 years; 72.9% women) completed the trial. The mean daily duration of visits was significantly higher with flexible visitation (4.8 vs 1.4 hours; adjusted difference, 3.4 hours [95% CI, 2.8 to 3.9]; P < .001). The incidence of delirium during ICU stay was not significantly different between flexible and restricted visitation (18.9% vs 20.1%; adjusted difference, -1.7% [95% CI, -6.1% to 2.7%]; P = .44). Among 9 prespecified secondary outcomes, 6 did not differ significantly between flexible and restricted visitation, including ICU-acquired infections (3.7% vs 4.5%; adjusted difference, -0.8% [95% CI, -2.1% to 1.0%]; P = .38) and staff burnout (22.0% vs 24.8%; adjusted difference, -3.8% [95% CI, -4.8% to 12.5%]; P = .36). For family members, median anxiety (6.0 vs 7.0; adjusted difference, -1.6 [95% CI, -2.3 to -0.9]; P < .001) and depression scores (4.0 vs 5.0; adjusted difference, -1.2 [95% CI, -2.0 to -0.4]; P = .003) were significantly better with flexible visitation. Conclusions and Relevance: Among patients in the ICU, a flexible family visitation policy, vs standard restricted visiting hours, did not significantly reduce the incidence of delirium. Trial Registration: ClinicalTrials.gov Identifier: NCT02932358.

Phylogeography of Nasutitermes corniger (Isoptera: Termitidae) in the Neotropical Region.

BACKGROUND: The Neotropical Region is known for its biodiversity and ranks third in number of known termite species. However, biogeographic and phylogeographic information of termites of this region is limited compared to other world geographic regions. Nasutitermes corniger is widely distributed in the region and is of considerable economic importance. The goal of this study was to describe the phylogeography of N. corniger in the Neotropical Region, to better understand its evolutionary processes. RESULTS: The sampled populations of N. corniger showed high genetic variation. Results indicated strong geographic structure among N. corniger populations, with most haplotypes not broadly shared among separated locations. Phylogeographic analyses showed a dispersal route for N. corniger from Central America into South America via the Isthmus of Panama, with subsequent dispersal through the highlands east of the Andes and into eastern regions of the continent. The majority of haplotypes were limited in distribution to proximal regions, corresponding to particular biomes (Atlantic Forest, Amazonia, Chaco, Cerrado and Caatinga). CONCLUSIONS: Nasutitermes corniger is suggested to be a good model for biogeographic and phylogeographic studies in the Neotropical Region. This study clarified the phylogeographic history of N. corniger and can contribute to the understanding of biogeographic dispersion processes in the Neotropical Region.

Identification of fungi isolated from banana rachis and characterization of their surface activity.

Filamentous fungi are an unexplored source for the production of biosurfactants, but over a decade one of the most surface active molecules called hydrophobins was discovered. There are few techniques to determine the surface activity of fungi without any kind of manipulation that can affect the final results. In this work, we identified 33 strains of filamentous fungi isolated from banana rachis which may have potential in producing biosurfactants. Further, the production of surface active compounds by the strains was measured by two techniques. First, the surface tension of supernatants was evaluated in liquid cultures of the strains. We found that three strains belonging to the genus Fusarium, Penicillium and Trichoderma showed activity in the reduction of surface tension, which indicate a putative production of biosurfactants. Second, we measured the contact angle between the drop of water and the solid culture of strains to determine the surface activity of cells, classifying the strains as hydrophilic or hydrophobic. These techniques can be used as a quantitative measurement of the surface activity of fungi without cell manipulation. SIGNIFICANCE AND IMPACT OF THE STUDY: Biosurfactants are an alternative to petrochemical derivatives, and filamentous fungi are a promising source of these molecules. This work identified 33 strains of filamentous fungi in agroindustrial wastes. This is important because these results open the opportunity of finding new biosurfactants (hydrophobins) with unique properties. We propose the evaluation of surface tension in the supernatant as a quantitative screening to determine the production of biosurfactants from the strains of fungi.

Phytotoxicity as an indicator of stability of broiler production residues.

Beddings used for successive broiler lots act as substrate to absorb water and feed from the excreta and may be subsequently used as agricultural fertilizers. This study evaluated the physicochemical characteristics and the phytotoxicity of beddings used to raise five consecutive broiler lots in five aviaries. Samples were collected for beddings not used yet and for beddings used at each of the five broiler lots. Lettuce and cucumber seeds were considered as phytotoxicity bioindicators. As beddings were used for greater number of lots, N, Ca, K, Mg and P contents generally increased, but the C content decreased, the pH alkalinized and humidity was reduced (P < 0.05). The germination index for lettuce and cucumber seeds was reduced with increased bedding (P < 0.05). Beddings used for at least five broiler lots presented decreased C:N ratio and would not recommended for agricultural use due to its toxicity for both tested seeds.

A multi-ontology approach to annotate scientific documents based on a modularization technique.

Scientific text annotation has become an important task for biomedical scientists. Nowadays, there is an increasing need for the development of intelligent systems to support new scientific findings. Public databases available on the Web provide useful data, but much more useful information is only accessible in scientific texts. Text annotation may help as it relies on the use of ontologies to maintain annotations based on a uniform vocabulary. However, it is difficult to use an ontology, especially those that cover a large domain. In addition, since scientific texts explore multiple domains, which are covered by distinct ontologies, it becomes even more difficult to deal with such task. Moreover, there are dozens of ontologies in the biomedical area, and they are usually big in terms of the number of concepts. It is in this context that ontology modularization can be useful. This work presents an approach to annotate scientific documents using modules of different ontologies, which are built according to a module extraction technique. The main idea is to analyze a set of single-ontology annotations on a text to find out the user interests. Based on these annotations a set of modules are extracted from a set of distinct ontologies, and are made available for the user, for complementary annotation. The reduced size and focus of the extracted modules tend to facilitate the annotation task. An experiment was conducted to evaluate this approach, with the participation of a bioinformatician specialist of the Laboratory of Peptides and Proteins of the IOC/Fiocruz, who was interested in discovering new drug targets aiming at the combat of tropical diseases.

A simple mathematical model that describes the growth of the area and the number of total and viable cells in yeast colonies.

UNLABELLED: We propose a model, based on the Gompertz equation, to describe the growth of yeasts colonies on agar medium. This model presents several advantages: (i) one equation describes the colony growth, which previously needed two separate ones (linear increase of radius and of the squared radius); (ii) a similar equation can be applied to total and viable cells, colony area or colony radius, because the number of total cells in mature colonies is proportional to their area; and (iii) its parameters estimate the cell yield, the cell concentration that triggers growth limitation and the effect of this limitation on the specific growth rate. To elaborate the model, area, total and viable cells of 600 colonies of Saccharomyces cerevisiae, Debaryomyces fabryi, Zygosaccharomyces rouxii and Rhodotorula glutinis have been measured. With low inocula, viable cells showed an initial short exponential phase when colonies were not visible. This phase was shortened with higher inocula. In visible or mature colonies, cell growth displayed Gompertz-type kinetics. It was concluded that the cells growth in colonies is similar to liquid cultures only during the first hours, the rest of the time they grow, with near-zero specific growth rates, at least for 3 weeks. SIGNIFICANCE AND IMPACT OF THE STUDY: Mathematical models used to predict microbial growth are based on liquid cultures data. Models describing growth on solid surfaces, highlighting the differences with liquids cultures, are scarce. In this work, we have demonstrated that a single Gompertz equation describes accurately the increase of the yeast colonies, up to the point where they reach their maximum size. The model can be used to quantify the differences in growth kinetics between solid and liquid media. Moreover, as all its parameters have biological meaning, it could be used to build secondary models predicting yeast growth on solid surfaces under several environmental conditions.

Oropouche Virus Exposure in Febrile Patients during Chikungunya Virus Introduction in the State of Amapá, Amazon Region, Brazil.

Oropouche orthobunyavirus (OROV) is an arbovirus transmitted by midges that has been involved in outbreaks throughout Central and South America. In Brazil, human cases have been historically concentrated in the northern region of the country. Oropouche fever in humans range from mild clinical signs to rare neurological events, and is considered a neglected tropical disease in Brazil. Due to the clinical similarities to other arboviruses, such as chikungunya and dengue viruses, OROV infections are likely to be underreported. Chikungunya virus (CHIKV) cases in Brazil were first recognized in 2014 in the states of Amapá and Bahia in the north and northeast regions, respectively. Both OROV and CHIKV cause nonspecific symptoms, making clinical diagnosis difficult in a scenario of arbovirus cocirculation. Aiming to investigate OROV transmission during the CHIKV introduction in the state of Amapá located in the Brazilian Amazon, we conducted a retrospective molecular (RT-qPCR) and serological investigation in febrile cases (N = 166) collected between August 2014 and May 2015. All acute serum samples were negative for OROV RNA using RT-qPCR. However, neutralizing antibodies for OROV were detected using a plaque reduction neutralization test (PRNT90) in 10.24% (17/166) of the patients, with neutralizing antibody titers ranging from 20 to ≥640, suggesting the previous exposure of patients to OROV. Regarding CHIKV, recent exposure was confirmed by the detection of CHIKV RNA in 20.25% (33/163) of the patients and by the detection of anti-CHIKV IgM in 28.57% (44/154) of the patients. The additional detection of anti-CHIKV IgG in 12.58% (19/151) of the febrile patients suggests that some individuals had been previously exposed to CHIKV. Whether the OROV exposure reported here occurred prior or during the CHIKV circulation in Amapá, is unknown, but because those arboviral infections share similar clinical signs and symptoms, a silent circulation of enzootic arboviruses during the introduction of exotic arboviruses may occur, and highlights the importance of syndromic cases' surveillance to arboviruses in Brazil.

Current management of non-muscle-invasive bladder cancer.

AIM: Despite standard treatment with transurethral resection (TURBT) and adjuvant therapy, many bladder cancers (BCs) recur and some progress. Based on a review of the literature, we aimed to establish the optimal current approach for the early diagnosis and management of non-muscle-invasive bladder cancer (NMIBC). METHODS: A Medline® search was conducted to identify the published literature relating to early identification and treatment of NMIBC. Particular attention was paid to factors such as quality of TURBT, importance of second TUR, substaging, and carcinoma in situ. In addition, studies on urinary markers, photodynamic diagnosis, predictive clinical and molecular factors for recurrence and progression after BCG, and best management practice were analyzed. RESULTS: Good quality of TUR and the implementation of photodynamic diagnosis in selected cases provide a more accurate diagnosis and reduce the risk of residual tumor in bladder cancer. Although insufficient evidence is available to warrant the use of new urinary molecular markers in isolation, their use in conjunction with cytology and cystoscopy can improve early diagnosis and follow-up. BCG plus maintenance for at least one year remains the standard adjuvant treatment in high-risk BC. Moreover, there is enough evidence to consider the implementation of new specific risk tables for patients treated with BCG. CONCLUSION: In high-risk patients with poor prognostic factors after TUR, early cystectomy should be considered.

Loricaria luciae, a new species of whiptail catfish (Siluriformes: Loricariidae) from the Paraguay and lower Paraná River basins of southeastern South America.

Loricaria luciae, new species, is described from the the rio Paraguay basin of Bolivia, Brazil, and Paraguay, south to its confluence with the rio Paraná in Argentina. It is distinguished from all congeners by the following combination of characteristics: pectoral girdle entirely naked or with small isolated plates near base of pectoral fin, post-ural plate at base of caudal fin large (plate length 17.0-20.3% HL), and total lateral plates 32-33 (modally 32). The new species occurs in a variety of habitats ranging from small, seasonally intermittent streams with clear water to large, turbid rivers over sand and mud substrates. It is sympatric with at least three other species of Loricaria in the Paraguay and lower Paraná drainages, including L. apeltogaster Boulenger 1895, L. coximensis Rodriguez et al. 2012, and L. simillima Regan 1904. 

Two-step hot isostatic pressing densification achieved non-porous fully-densified wood with enhanced physical and mechanical properties.

A new two-step densification method for wooden materials entitled hot isostatic pressing (HIP) is proposed. This method has the advantage over previous densification methods that can achieved almost the full densification of wood, reaching values up to 1.47 kg/m3, which exceeds any value ever reported for a hardwood species. Furthermore, it can preserve about 35% of the original volume, in comparison to other methods which typically can preserve only 20% of the volume. Although not tested in this investigation, in principle, the HIP method should be capable of densifying any shape of wood including circular and tubular cross sections because the main densification mechanism is based on gas pressure that is equally exerted in the entire surface, rather than localized mechanical compression, which can only be effective with rectangular cross sections. In the first stage of the two-step proposed method, the compressive strength of the anatomical wood structure is reduced by delignification, and, in the second, a full densification is achieved by hot isostatic pressing under argon atmosphere. Three tropical hardwood species with distinct anatomical characteristics and properties were used to test the method. The HIP-densified wood's microstructural, chemical, physical, and mechanical properties were assessed. Apart from the high densification values and volume preservation, the results indicate that proposed method was effective for all the tested species, showing homogenous density patterns, stable densification without noticeable shape recovery, and enhanced mechanical properties. Future research should test the HIP method in softwoods and consider the ring orientation in order to enhance the control of the densified geometry.

Histomorphological changes between short and long days in ovary guanacos (Lama guanicoe).

This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERß) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERß was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries.

Toxicity and physicochemical parameters of composts including distinct residues from agribusiness and slaughterhouse sludge.

Composting is useful for treatment of residues from agribusiness, but the potential toxicity of the final compost should be evaluated before its agricultural destination. The objective of this study was to evaluate the physicochemical characteristics and the toxicity of agribusiness residues using onion seeds as bioindicators. All tested treatments were composed by sludge from a swine slaughterhouse and sawdust. Besides the control, which included no additional materials, the other treatments included aviary bedding, rice husk and residue from tobacco industries as structuring materials. After 120 days of composting, for all treatments, the temperature inside the composting piles approached the environmental temperature, the physicochemical parameters indicated that the composts were stabilized and, except for the treatment including tobacco residues, that could be used for agriculture without impairing plant germination. Although the treatments including tobacco residues and rice husk showed evidence of cytotoxicity and genotoxicity at the beginning of the composting period, that was not observed for the treatment including aviary bedding. Such potential toxicity was not observed at the end of composting for any of the tested treatments.

Moisture content monitoring in industrial-scale composting systems using low-cost sensor-based machine learning techniques.

Moisture is a key aspect for proper composting, allowing greater efficiency and lower environmental impact. Low-cost real-time moisture determination methods are still a challenge in industrial composting processes. The aim of this study was to design a model of hardware and software that would allow self-adjustment of a low-cost capacitive moisture sensor. Samples of organic composts with distinct waste composition and from different composting stages were used. Machine learning techniques were applied for self-adjustment of the sensor. To validate the model, results obtained in a laboratory by the gravimetric method were used. The proposed model proved to be efficient and reliable in measuring moisture in compost, reaching a correlation coefficient of 0.9939 between the moisture content verified by gravimetric analysis and the prediction obtained by the Sensor Node.

Binge Eating and Compulsive Buying During Cabergoline Treatment for Prolactinoma: A Case Report.

Prolactinomas are the most prevalent functional pituitary adenomas. They are usually treated clinically with dopamine agonists. The most widely used and suitable drug is cabergoline (CAB), a specific D2 dopamine agonists. Patients in prolactinoma treatment with CAB commonly report physical side effects, but aberrant behavioral changes such as increased impulsivity have also been reported recently. We report the case of a 47-year-old Brazilian woman with prolactinoma that developed compulsive buying, binge eating, and hypersexuality after four years of CAB treatment. In her psychiatric evaluation, the patient scored high levels on the following scales: Compulsive Buying Scale (CBS), Binge Eating Scale (BES), and Barratt Impulsiveness Scale-11 (BIS11). She also reported financial problems and weight gain in addition to her social and clinical problems. Impulsivity disorders may appear with the use of CAB and other dopamine agonists. We suggest that more observational studies with a large patient sample and specific regular psychiatric evaluations during treatment are necessary for patients in use of CAB, especially those treated for several years.

Comparative Study on the Efficiency of Mercury Removal From Wastewater Using Bacterial Cellulose Membranes and Their Oxidized Analogue.

A comparative study was conducted on the efficiency of mercury removal using bacterial nanocellulose (BNC) membranes obtained from the fermentation of the microorganism Komagataeibacter medellinensis, in contrast with its oxidized analog obtained by modifying the bacterial nanocellulose membranes via oxidation with 2,2,6,6-Tetramethylpiperidine-1-oxyl. Both types of membranes (modified and unmodified) were characterized to identify variations in the Physico-chemical parameters after modification. FTIR spectra confirmed the chemical modification of cellulose in all reaction conditions by the presence of a new characteristic band at ∼1730 cm-1, corresponding to the new carboxylic groups produced by the oxidative process, and the decline of the band at ∼1,650 cm-1, corresponding to the hydroxyl groups of the C6 carbon. While the XRD profiles indicated that the percentage of BNC crystallinity decreased and the SEM images showed that the nanoribbon network was interrupted as the amount of oxidizing agent increased. The kinetics of mercury removal from both types of membrane was evaluated by calculating the concentration of mercury at different times and establishing a mathematical model to describe the kinetics of this process. The modified membranes improved significantly the adsorption process of the metal ion and it was found that the modification that results in the greatest adsorption efficiency was BNC-m 7.5 with a value of 92.97%. The results obtained suggest that the modification of the bacterial nanocellulose membranes by oxidation transcendentally improves the mercury removal capacity, outlining the modified membranes as an excellent material for mercury removal in wastewater.

Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling.

BACKGROUND: With nearly 1,100 species, the fish family Characidae represents more than half of the species of Characiformes, and is a key component of Neotropical freshwater ecosystems. The composition, phylogeny, and classification of Characidae is currently uncertain, despite significant efforts based on analysis of morphological and molecular data. No consensus about the monophyly of this group or its position within the order Characiformes has been reached, challenged by the fact that many key studies to date have non-overlapping taxonomic representation and focus only on subsets of this diversity. RESULTS: In the present study we propose a new definition of the family Characidae and a hypothesis of relationships for the Characiformes based on phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes (4,680 base pairs). The sequences were obtained from 211 samples representing 166 genera distributed among all 18 recognized families in the order Characiformes, all 14 recognized subfamilies in the Characidae, plus 56 of the genera so far considered incertae sedis in the Characidae. The phylogeny obtained is robust, with most lineages significantly supported by posterior probabilities in Bayesian analysis, and high bootstrap values from maximum likelihood and parsimony analyses. CONCLUSION: A monophyletic assemblage strongly supported in all our phylogenetic analysis is herein defined as the Characidae and includes the characiform species lacking a supraorbital bone and with a derived position of the emergence of the hyoid artery from the anterior ceratohyal. To recognize this and several other monophyletic groups within characiforms we propose changes in the limits of several families to facilitate future studies in the Characiformes and particularly the Characidae. This work presents a new phylogenetic framework for a speciose and morphologically diverse group of freshwater fishes of significant ecological and evolutionary importance across the Neotropics and portions of Africa.

Dealing with cancer screening in the COVID-19 era.

OBJECTIVE: This article aims to alert health professionals for cancer screening in the face of the possibility of new waves of disease. METHODS: A narrative review was conducted through a search in MEDLINE, Lilacs, Chinese Biomedical Literature Database, and international medical societies publications. RESULTS: Breast cancer: in high-risk patients (confirmed familial cancer syndrome or with high-risk tools scores), clinicians should act according to usual recommendations; in average-risk individuals, consider screening with mammography with a longer time span (maximum of two years). Cervical cancer: women turning 25 years old who have already been immunized and with no previous Pap test can have the test postponed during the pandemic; if there is no previous dose of Human Papillomavirus vaccination, initiation of screening should be recommended following a more rigid approach for COVID prevention; in women over 30 years of age who have never participated in cervical screening, the first screening exam is also essential. Colorectal cancer: if the individual is at elevated risk for familial cancer, the screening with colonoscopy according to usual recommendations should be supported; if at average risk consider screening with Fecal Occult Blood Test. Prostate cancer: there is a trend to postpone routine prostate cancer screening until the pandemic subsides. CONCLUSIONS: The decision to keep cancer screening must be discussed and individualized, considering the possibility of new waves of COVID-19.

Cetaceans along the southeastern Brazilian coast: occurrence, distribution and niche inference at local scale.

It is deemed important to understand cetacean occurrence and distribution to comprehend their ecological roles. The geographical occurrence of species' niche can be used to better describe their potential distribution. The niche can be defined using environmental variables. Those variables are considered static and not affected by biological activities. The present study goal was to assess the occurrence and distribution of cetaceans along the southeastern Brazilian coast, as well as to define the fundamental and realized niche of each species and to investigate niche overlap at local scale. The environmental requirements for each species were also investigated throughout statistical tests. Sighting data were obtained through oceanographic surveys conducted between 2012 and 2015. The environmental variables available on MARSPEC and the software NicheA were used for the ecological niche modeling. A total of twelve cetacean species were identified and the potential distribution areas of the six commonest ones were defined. Even though the species presented different environmental preferences, most of them had partial overlap among niches and potential distribution areas. The environmental heterogeneity of the study area might support the co-occurrence of different species with different environmental requirements.