DBIO - Departamento Biologia

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Acute and chronic alcohol administration: effects on performance of zebrafish in a latent learning task
(Elsevier, 2015) Luchiari, Ana Carolina; Salajan, Diana C.; Gerlai, Robert
Alcohol abuse is a major medical problem. Zebrafish have been proposed to model alcohol related human disorders. Alcohol impairs learning and memory. Here, we analyze the effects of alcohol on performance of zebrafish in a recently developed latent learning paradigm. We employ a 2 × 3 × 2 experimental design (chronic × acute alcohol treatment × path blocked). The latent learning task had two phases: one, 30 min long exploration trials (16 days, 1 trial/day) with left or right path of a complex maze blocked, and two, a subsequent probe trial with all paths open leading to a goal box that now contained stimulus fish. During the 16 days each fish received one of two chronic treatments: freshwater or 0.50% (v/v%) alcohol. Subsequently, fish were immersed for 1 h in one of the following solutions: 0.00 (freshwater), 0.50% or 1.00% alcohol, the acute challenge. Behavior of fish was recorded during the probe trial that commenced immediately after the acute treatment. Path choices, latency to leave the start box and to enter the goal box, time spent in the goal box, distance traveled, and duration of freezing were quantified. We found that acute exposure to 1.00% alcohol after chronic freshwater disrupted learning performance, so did exposure to freshwater after chronic alcohol treatment (withdrawal). We also found exposure to chronic alcohol to diminish the effect of subsequent acute alcohol suggesting development of tolerance. Our results demonstrate that analysis of learning performance of zebrafish allows detection of alcoholinduced functional changes. The simplicity and scalability of the employed task also imply the utility of the zebrafish in high throughput drug screens
Adjustments in the time, distance and direction of foraging in dinoponera quadriceps workers
(Springer, 2014) Azevedo, Dina L. O.; Medeiros, Jeniffer C.; Araújo, Arrilton
We measured individual decisions regarding the adjustments of time, distance and direction of foraging in Dinoponera quadriceps.We observed two colonies in an area of secondary Atlantic Forest, FLONA-ICMBio, in Northeastern Brazil. The workers were individually marked. We recorded the displacement of workers, their returns to the nest with and without food, the time spent searching for food, maximum and total distance, inter-trip latency and direction of trips. The time spent searching for food, maximum distance and transport velocity did not vary with food size. The previous trip success reduced the latency between foraging trips and increased the percentage of success on the next trip. However, this previous success did not demonstrate a significant variation relative to the time spent searching on the next trip or direction of search. The workers maintained an individual directional fidelity during foraging. The adjustments of these foraging variables under individual control contributed to the efficiency at the colony level. D. quadriceps is compatible with the central place theory and risk sensitivity model of behavior
Anticonvulsant effects of fractions isolated from dinoponera quadriceps (Kempt) ant venom (Formicidae: ponerinae)
(Multidisciplinary Digital Publishing Institute, 2017) Nôga, Diana Aline Morais Ferreira; Brandão, Luiz Eduardo Mateus; Cagni, Fernanda Carvalho; Silva, Delano; Azevedo, Dina Lilia Oliveira de; Araújo, Arrilton; Santos, Wagner Ferreira dos; Miranda, Antonio; Silva, Regina Helena da; Ribeiro, Alessandra Mussi
Natural products, sources of new pharmacological substances, have large chemical diversity and architectural complexity. In this context, some toxins obtained from invertebrate venoms have anticonvulsant effects. Epilepsy is a neurological disorder that affects about 65 million people worldwide, and approximately 30% of cases are resistant to pharmacological treatment. Previous studies from our group show that the denatured venom of the ant Dinoponera quadriceps (Kempt) protects mice against bicuculline (BIC)-induced seizures and death. The aim of this study was to investigate the anticonvulsant activity of compounds isolated from D. quadriceps venom against seizures induced by BIC in mice. Crude venom was fractionated by high-performance liquid chromatography (HPLC) resulting in six fractions referred to as DqTx1–DqTx6. A liquid chromatography-mass spectrometry (LC/MS) analysis revealed a major 431 Da compound in fractions DqTx1 and DqTx2. Fractions DqTx3 and DqTx4 showed a compound of 2451 Da and DqTx5 revealed a 2436 Da compound. Furthermore, the DqTx6 fraction exhibited a major component with a molecular weight of 13,196 Da. Each fraction (1 mg/mL) was microinjected into the lateral ventricle of mice, and the animals were observed in an open field. We did not observe behavioral alterations when the fractions were given alone. Conversely, when the fractions were microinjected 20 min prior to the administration of BIC (21.6 nM), DqTx1, DqTx4, and DqTx6 fractions increased the latency for onset of tonic-clonic seizures. Moreover, all fractions, except DqTx5, increased latency to death. The more relevant result was obtained with the DqTx6 fraction, which protected 62.5% of the animals against tonic-clonic seizures. Furthermore, this fraction protected 100% of the animals from seizure episodes followed by death. Taken together, these findings indicate that compounds from ant venom might be a potential source of new anticonvulsants molecules
Aspectos alimentares e reprodutivos do cascudo, hypostomus pusarum (starks, 1913) (osteichthyes: loricariidae) no açude Marechal Dutra, Rio Grande do Norte, Brasil
(Universidade Federal do Amapá (UNIFAP), 2013) Pessoa, Emilly Kataline Rodrigues; Lima, Louise Thuanne Barreto de; Chellappa, Naithirithi T.; Souza, Arrilton Araújo de; Chellappa, Sathyabama
O peixe cascudo, Hypostomus pusarum é de importância ecológica e econômica dos ecossistemas aquáticos da região neotropical. O presente estudo verificou os aspectos alimentares e reprodutivos dessa espécie no açude Marechal Dutra, Acari, Rio Grande do Norte. As capturas dos peixes foram realizadas durante o período de julho de 2011 a junho de 2012, com o auxílio de pecadores locais, que utilizaram redes de espera e tarrafas. Os itens alimentares do estômago de H. pusarum foram identificados até o nível taxonômico mais inferior possível. Foi capturado um total de 118 exemplares de H. pusarum e no laboratório eles foram numerados, pesados, medidos, dissecados e o sexo foi identificado. Foram verificadas a proporção sexual, a relação peso-comprimento, o conteúdo estomacal, o índice gonadossomático (IGS), o fator de condição (K), a fecundidade e o período reprodutivo de H. pusarum. Houve uma predominância de fêmeas (n=67; 55,3%) sobre os machos (n=51; 44,7%). H. pusarum apresenta um crescimento do tipo alométrico negativo, ganhando mais incremento em comprimento do que em peso. A espécie em estudo apresentou uma dieta baseada em material orgânico em decomposição (88,7%) e microalgas (11,3%) consistindo de Bacilariofíceas, Clorofíceas e Cianobacteria. O índice gonadossomático (IGS) dos machos variou de 0,483 a 7,502 e das fêmeas de 3,408 a 10,533. A média do fator de condição (K) dos machos foi de 0,089 e das fêmeas foi de 0,266. A fecundidade absoluta apresentou a média de 756,85. Os peixes apresentaram gônadas em várias fases de maturação durante o período de estudo e a caracterização macroscópica das gônadas indicou quatro estádios de maturação, sendo imaturo, em maturação, maduro e esvaziado. O período reprodutivo de H. pusarum foi indicado pelo pico de IGS durante janeiro a abril
Associative learning in the multichamber tank: a new learning paradigm for zebrafish
(Elsevier, 2016-06-21) Fernandes, Yohaan M.; Rampersad, Mindy; Luchiari, Ana Carolina; Gerlai, Robert
The zebrafish has been gaining prominence in the field of behavioural brain research as this species offers a good balance between system complexity and practical simplicity. While the number of studies examining the behaviour of zebrafish has exponentially increased over the past decade, the need is still substantial for paradigms capable of assessing cognitive and mnemonic characteristics of this species. Here we describe and utilize a novel visual discrimination task with which we evaluated acquisition of CS (colour)-US (sight of conspecifics) association in adult zebrafish. We report significant acquisition of CS-US association indicated by the increased time the fish spent in and the increased frequency of visits of the target chamber during a probe trial in the absence of reward. Given the simplicity of the apparatus and procedure, we conclude that the new task may be employed to assay learning and memory in adult zebrafish in an efficient manner
Behavioral changes over time following ayahuasca exposure in zebrafish
(2017-07-28) Savoldi, Robson; Polari, Daniel; Silva, Jaquelinne Pinheiro da; Silva, Priscila; Soares, Bruno Lobao; Yonamine, Mauricio; Freire, Fúlvio Aurélio de Morais; Luchiari, Ana Carolina
The combined infusion of Banisteriopsis caapi stem and Psychotria viridis leaves, known as ayahuasca, has been used for centuries by indigenous tribes. The infusion is rich in N, N-dimethyltryptamine (DMT) and monoamine oxidase inhibitors, with properties similar to those of serotonin. Despite substantial progress in the development of new drugs to treat anxiety and depression, current treatments have several limitations. Alternative drugs, such as ayahuasca, may shed light on these disorders. Here, we present time-course behavioral changes induced by ayahuasca in zebrafish, as first step toward establishing an ideal concentration for pre-clinical evaluations. We exposed adult zebrafish to five concentrations of the ayahuasca infusion: 0 (control), 0.1, 0.5, 1, and 3 ml/L (n D 14 each group), and behavior was recorded for 60 min. We evaluated swimming speed, distance traveled, freezing and bottom dwelling every min for 60 min. Swimming speed and distance traveled decreased with an increase in ayahuasca concentration while freezing increased with 1 and 3 ml/L. Bottom dwelling increased with 1 and 3 ml/L, but declined with 0.1 ml/L. Our data suggest that small amounts of ayahuasca do not affect locomotion and reduce anxiety-like behavior in zebrafish, while increased doses of the drug lead to crescent anxiogenic effects. We conclude that the temporal analysis of zebrafish behavior is a sensitive method for the study of ayahuasca-induced functional changes in the vertebrate brain
Behavioral strategies and hormonal profiles of dominant and subordinate common marmoset (callithrix jacchus) females in wild monogamous groups
(Wiley, 2005) Sousa, Maria Bernadete Cordeiro; Rocha, Ana Claudia Sales da; Albuquerque, Fabiola da Silva; Souza, Arrilton Araújo de; Yamamoto, Maria Emilia; Arruda, Maria de Fatima
New insights into the mating systems of common marmosets suggest that they are mainly monogamous, although polygyny and polyandry occasionally occur. Long-term monitoring of wild common marmosets has shown that some reports of polygynous groups (i.e., groups that contain more than one reproducing female) in fact indicate an unbalanced reproductive output associated with extragroup copulation. In this study we describe the behavioral and hormonal profiles of common marmoset (Callithrix jacchus) females living in three wild monogamous groups (Q, PBf, and T), varying from five to 11 individuals, at Nı´sia Floresta field station, RN, Brazil. The mating system of the groups was previously characterized in terms of affiliative, sexual, and mate-guarding behaviors. Behavioral data were collected once a week, and fecal samples were collected at least twice a week for 10–16 months, depending on the group. A preferential allogrooming relationship was recorded between dominant males and females. Under field conditions the reproductive inhibition of subordinate females appears to be more behavioral than hormonal, since subordinate females of the three groups ovulated and two conceived during the study. In these cases, the subordinate and dominant females reproduced 1 month apart, and infanticide (one case confirmed and one suspected) appeared to be part of the reproductive strategy of dominant females. Following the infanticide, ovarian inhibition (group T) or emigration and return to the natal group (group PBf) were observed. In the third group (Q) the subordinate female, showed hormonal profiles compatible with pregnancy, but no infants were seen. These findings reflect the different alternatives that wild subordinate common marmoset females use to reproduce.
Biologia reprodutiva do peixe mussum, synbranchus marmoratus bloch, 1975 no açude Marechal Dutra, Rio Grande do Norte, Brasil
(Universidade Federal do Amapá (UNIFAP), 2013) Barros, Nirlei Hirachy Costa; Nascimento, Wallace Silva; Araújo, Andréa Soares; Souza, Arrilton Araújo de; Chellappa, Sathyabama
A biologia reprodutiva do peixe hermafrodita mussum, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) foi investigada no açude Marechal Dutra, Acari, Rio Grande do Norte, utilizando os exemplares capturados mensalmente no período de julho de 2010 á janeiro de 2011. Os peixes capturados foram numerados, pesados, medidos, dissecados as e gônadas foram retiradas, pesadas e identificadas quanto ao sexo. A relação peso-comprimento foi determinada para sexos agrupados. O índice gonadossomático (IGS) e o fator de condição (K) foram verificados. As fases do desenvolvimento das gônadas foram investigadas usando técnicas macroscópicas. As características macroscópicas do desenvolvimento gonadal mostraram quatro tipos sexuais diferentes na população dos peixes capturados, sendo: machos primários, fêmeas, intersexos e machos secundários. As fêmeas foram mais frequentes durante todo o período de estudo (74%). A espécie mostrou um crescimento do tipo alométrico negativo, com maior incremento em comprimento do que em peso. O fator de condição mostrou seu menor valor no mês de agosto e dois picos sendo, um em dezembro de 2010 e outro em janeiro de 2011. O IGS indicou um período reprodutivo que vai de julho a agosto de 2010, mostrando correlação negativa ao fator de condição. S. marmoratus mostra uma estratégia reprodutiva sazonal que aperfeiçoa seu sucesso reprodutivo dentro das condições climáticas do semiárido
Body weight of wild and captive common marmosets (callithrix jacchus)
(Springer Velag, 2000) Araújo, Arrilton; Arruda, M. F.; Alencar, A. I.; Albuquerque, F.; Nascimento, M. C.; Yamamoto, M. E.
Captive studies and occasional trappings of wild individuals indicate that callitrichids have small size and body weight and lack sexual dimorphism. We compared body weights of captive and wild Callithrix jacchus obtained by repeatedly weighing subjects from two populations in Brazil. We obtained captive data by routinely weighing 138 individuals from the Universidade Federal do Rio Grande do Norte colony and wild data via regular trapping of 243 individuals in 15 free-ranging groups from IBAMA’s field site in Nı´sia Floresta. We assigned all subjects to one of four age classes—infant, juvenile, subadult, and adult—according to their birth dates or size, reproductive status, and dental development. There is no significant difference between males and females in any of the four age classes, but captive subjects were heavier than wild ones in all age classes but infant. Reproductive and nonreproductive adult females showed no statistical difference in weight. These results accord with previous reports of lack of body size sexual dimorphism in common marmosets and suggest that differences between wild and captive common marmosets are not constitutional, but are instead a consequence of diet and physical activity. The absence of weight difference between reproductive and nonreproductive females suggests that any possible advantage from high rank is outweighed by the costs of reproduction in common marmosets
Changes in sleep habits and knowledge after an educational sleep program in 12th grade students
(Wiley, 2013) Sousa, Ivanise Cortez; Souza, Jane Carla; Louzada, Fernando Mazzilli; Azevedo, Carolina Virginia Macêdo
The objective of this research was to evaluate the effect of an education program using the meaningful learning approach on sleep knowledge and habits of 12th grade students. Thirty-four student volunteers (aged 16.8 0.6 years) were divided into intervention (Sleep Education Program – SEP) and control groups. Sleep knowledge and habits were assessed by the “health and sleep” questionnaire. Also, the students filled out a sleep diary and the Karolinska Sleepiness Scale by one week (Stage 1). These procedures were repeated 3 weeks after the SEP (Stage 2) that was evaluated by a questionnaire. The SEP consisted of five 50-minute classes to discuss the physiological and behavioral processes of sleep and healthy lifestyle. At Stage 2, the intervention group increased the percentage of correct responses in 63% of the questions. On weekdays, they increased time in bed by 26 min, woke up 11 min later and showed a tendency to go to bed 18 min earlier (P = 0.07). On weekends, they advanced bedtime and wake-up times. These changes were associated with decreased irregularity at bedtimes and wake up times. These results were not observed in the control group, except the advance on wake up time on weekends. The frequency and duration of naps and daytime sleepiness levels did not differ between the stages for both groups. The SEP increased knowledge and contributed to positive changes in the adolescents’ sleep-wake cycle (SWC). However, daytime sleepiness levels remained unchanged probably due to an insufficient reduction on sleep deprivation to decrease its negative consequences
Changes in the suprachiasmatic nucleus during aging: implications for biological rhythms
(2013) Engelberth, Rovena C. G. J.; Pontes, André L. Bezerra de; Fiuza, Felipe Porto; Silva, Kayo D. de Azevedo; Resende, Nayra da S.; Azevedo, Carolina Virgínia de M.; Costa, Miriam S. M. O.; Cavalcante, Judney C.; Nascimento Júnior, Expedito S.; Gavioli, Elaine Cristina; Cavalcante, Jeferson S.
Animals have neural structures that allow them to anticipate environmental changes and then regulate physiological and behavioral functions in response to these alterations. The suprachiasmatic nucleus of the hypothalamus (SCN) is the main circadian pacemaker in many mammalian species. This structure synchronizes the biological rhythm based on photic information that is transmitted to the SCN through the retinohypothalamic tract. The aging process changes the structural complexity of the nervous system, from individual nerve cells to global changes, including the atrophy of total gray matter. Aged animals show internal time disruptions caused by morphological and neurochemical changes in SCN components. The effects of aging on circadian rhythm range from effects on simple physiological functions to effects on complex cognitive performance, including many psychiatric disorders that influence the well-being of the elderly. In this review, we summarize the effects of aging on morphological, neurochemical, and circadian rhythmic functions coordinated by the main circadian pacemaker, the SCN
Circadian activity rhythm in pre-pubertal and pubertal marmosets (callithrix jacchus) living in family groups
(Elsevier, 2016) Melo, Paula R.; Gonçalves, Bruno S. B.; Menezes, Alexandre A. L.; Azevedo, Carolina V. M.
In marmosets, a phase advancewas observed in activity onset in pubertal animals living in captivity under seminatural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythmin marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm
A Dose for the wiser is enough: the alcohol benefits for associative learning in zebrafish
(Elsevier, 2014) Chacon, Diana; Luchiari, Ana Carolina
This study aimed to test seeking behavior caused by alcohol and the drug effects on learning in the zebrafish, Danio rerio. Three treatments were conducted: acute, chronic and withdrawal, using 0.10%, 0.25%, and 1.00% alcohol and control (0.00%) (vol/vol.%). For the drug seeking behavior, we used a place preference paradigm (shuttle box tank) before and after alcohol exposure in acute (single exposure) and chronic (7 days) treatments. We observed a change in the basal preference due to the association with alcohol only for 0.25% and 1.00% doses in both acute and chronic offering, indicating an alcohol-seeking behavior after the drug exposure. For the learning task, two treatmentswere tested: chronic alcohol exposure (26 days including the learning period) and alcoholwithdrawal (15 days of alcohol exposure before the learning period). During the learning period, fish received light stimulus followed by food in a pre-defined area of the tank for 8 consecutive days. The low dose group (0.10%) learned the task by the 3rd day both in chronic and withdrawal treatments. The higher doses (0.25% and 1.00%) caused a learning impairment in the chronic treatment group, while fish from the alcohol withdrawal treatment displayed learning on the final testing day. Therefore, we suggest that high alcohol doses impair learning and cause drug seeking behavior, even after drug exposure cessation, while lowdoses positively affect learning and do not cause seeking behavior. Given our results we propose that the zebrafish is a promising model for identifying active compounds, antibodies or genes which modulate the alcohol dual effects: learning improvement and reinforcing behavior
Dose-dependent effects of alcohol on seeking behavior and memory in the fish betta splendens
(American Psychological Association, 2015) Luchiari, Ana Carolina; Chacon, Diana M.; Oliveira, Jéssica J.
The present study tested the effects of alcohol on seeking behavior and memory in the Siamese fighting fish Betta splendens. We tested behavior using 5 alcohol concentrations: .00%, .10%, .25%, 1.00%, and 1.50% (vol/vol%). Drug seeking was tested using a conditioned place preference (CPP) paradigm, with a single 20-min exposure to alcohol. The effect of alcohol on memory was tested using a T-maze protocol with acute (20 min/day for 5 days) and chronic (20 min/day for 20 days) alcohol exposure and after alcohol withdrawal (20 min/day alcohol exposure for 15 days water exposure). In the CPP test, the higher acute alcohol doses (1.00 and 1.50%) induced seeking behavior, but the lower (.10%) and medium (.25%) doses did not. When the fish were tested after 37 days of alcohol exposure, the higher-dose groups still exhibited seeking behavior, indicating that these doses may have caused drug addiction. In the memory test, we observed a dose-dependent pattern with both the acute and chronic treatments. High alcohol doses (1.00 and 1.50%) impaired memory, and low alcohol doses (.10%) caused an anticipatory response. The withdrawal group did not exhibit differences in memory, suggesting some capacity for recovery. The low alcohol doses did not impair memory or cause drug seeking, whereas the high doses affected memory and caused prolonged seeking behavior. Therefore, a dual effect of alcohol was corroborated by our data, and Betta splendens may be an adequate animal model for high-throughput screening with alcohol
Dusky damselfish Stegastes fuscus relational learning: evidences from associative and spatial tasks
(The Fisheries Society of the British Isles, 2015) Silveira, Mayara Moura da; Oliveira, Jessica Janine de; Luchiari, Ana Carolina
This study investigated the ability of the dusky damselfish Stegastes fuscus to associate conditioned and unconditioned stimuli (single CS–US) and to find a specific place in a clueless ambiece (spatial learning). After tested for colour preference and showing no specific colour attractively, the fish were trained to associate a colour cue with a stimulus fish (conspecific). Fish were then challenged to locate the exact place where the stimulus fish was presented. Stegastes fuscus spent most time close to the zone where stimulus was presented, even without obvious marks for orientation. The results confirm that S. fuscus show single CS–US learning and suggest the fish ability for spatial orientation. Stegastes fuscus appears to use multiple senses (sight and lateral line) for cues association and recall, and appear to perform relational learning similar to mammals. These data suggest the importance of cognitive skill for reef fishes that may have contributed to their establishment and evolutionary success in such complex environment
Dynamics of sex reversal in the marbled swamp eel (Synbranchus marmoratus bloch, 1795), a diandric hermaphrodite from Marechal Dutra Reservoir, northeastern Brazil
(Wiley, 2017) Barros, Nirlei Hirachy Costa; Souza, Arrilton Araújo de; Peebles, Ernst Bryan; Chellappa, Sathyabama
This study characterizes the dynamics of sex reversal in the marbled swamp eel, Synbranchus marmoratus (Osteichthyes: Synbranchidae), a diandric hermaphrodite, within the context of managing species with complex sex allocations. Monthly sampling in Marechal Dutra Reservoir, northeastern Brazil, was conducted using metal eel traps from July, 2013, to June, 2014, during which a total of 288 individuals were captured. Morphological and histological comparisons of gonads identified four sex types: primary males (n = 18), females (n = 197), transitional individuals (n = 30), and secondary males (n = 43). Primary males were smallest, ranging 18–32 cm total length. Females were numerically dominant throughout the 1-year sampling period, and ranged 20–60 cm. Transitional individuals ranged 32–60 cm, and secondary males ranged 46–74 cm. The otolith-based age of 52 specimens ranged 0.5 to 5+ year. Primary males were only observed at ages 0.5 and 1, and transitional individuals were only observed at ages 3 and 4 during the female-to- secondary- male transition, supporting the existence of two types of individuals: gonochoristic males and protogynous hermaphrodites. This observation was further supported by histological observations of deteriorating ovarian tissue in transitional individuals. Given the length of time required for individuals to attain secondary male status, this species appears to be particularly vulnerable to over-exploitation. Comparisons with results from other studies suggest sex allocations and adult size distributions vary substantially within this species’ range, adding complexity to management efforts
Effect of a sleep education program on sleep knowledge and habits in elementary and high school teachers
(2016) Souza, Jane Carla de; Galina, Sabinne Danielle; Sousa, Ivanise Cortez de; Azevedo, Carolina Virginia Macêdo de
The influence of a sleep education program (SEP) on the knowledge, habits, quality of sleep, and daytime sleepiness was evaluated in 40 Brazilian elementary and high school teachers [Groups: Experimental (EG=26)/Control (CG=14)]. The Health and Sleep questionnaire, Pittsburgh Sleep Quality Index and sleep logs were applied to both groups, at baseline and in reassessment three weeks after a SEP with the EG. The methodology of the SEP was based on the Meaningful Learning theory proposed by Ausubel, consisting of four fortnightly meetings, lasting 4h each. After the program, the EG showed an increase in sleep knowledge and a reduction in coffee consumption near bedtime. Besides, 17% of teachers improved sleep quality in this group. However, no changes occurred in sleep schedules and sleepiness. Nevertheless, the positive results reinforce the need for sleep education programs with teachers to spread sleep knowledge in schools and improve the sleep quality in these professionals
Effect of morning exercise in sunlight on the sleep-wake cycle in adolescents
(Instituto Brasileiro de Neuropsicologia e Comportamento (IBNeC), 2011) Maia, Ana Paula Leão; Sousa, Ivanise Cortez de; Azevedo, Carolina Virginia Macêdo de
A delay in bedtime occurs in adolescence compared with childhood. However, the early waking that morning school hours impose leads to partial sleep deprivation. Although exposure to light is the most important regulator of circadian rhythm in mammals, physical exercise influences circadian synchronization. To assess the effect of morning physical exercise in sunlight on the sleep-wake cycle (SWC) in adolescents, 160 first- and second-year high-school students were exposed to classes in their usual classroom (Group C) or in a swimming pool exposed to sunlight (Group E) while physically exercising (EE; i.e., swimming) or resting (EL). At baseline, we applied Health and Sleep and Horne & Ostberg chronotype assessment questionnaires. One week later and during the intervention, we applied the Sleep Diary and Karolinska Sleepiness Scale. During the intervention we observed no changes in bedtime, time in bed and in indices of irregularity of bedtime and wake-up time. The changes observed in wake-up time (i.e., a delay in the EE group on Saturday), sleep quality (i.e., an improvement), and sleepiness (i.e., an increase) were also observed in the control group, discarding an intervention effect. We suggest that morning physical exercise in sunlight had no effect on SWC parameters, sleep quality, or daytime sleepiness, possibly because of the large irregularity in the SWC between weekdays and weekends in adolescent students as well as the low frequency and duration of exercise during the intervention. Therefore, studies that evaluate a higher frequency or duration of exercise are needed to assess its effect on the SWC in adolescents
Fatores bióticos e abióticos que influenciam o desenvolvimento de branconeta (crustacea: anostraca)
(Universidade Estadual do Maranhão (UEMA), 2008) Lopes, José Patrocínio; Pontes, Cibele Soares; Souza, Arrilton Araújo de; Santos Neto, Miguel Arcanjo dos
Fatores bióticos e abióticos nos viveiros de cultivo da Estação de Piscicultura da CHESF e da região de Paulo Afonso, Bahia que influenciam no desenvolvimento de Dendrocephalus brasiliensis Pesta, 1921 foram investigados mediante monitoramento realizado em quatro viveiros de cultivo, no período de dezembro de 2004 a novembro de 2005. Para os fatores bióticos e abióticos referentes à qualidade da água dos viveiros estudados, o monitoramento, foi realizado em duas épocas do ano (maio e outubro) coincidindo com os períodos chuvoso e seco, respectivamente. O manejo dos viveiros que incluiu adubação orgânica e química e complementação dos níveis de água dos viveiros fez com que as variáveis limnológicas se situassem dentro de limites toleráveis para os crustáceos em estudo possibilitando aos mesmos crescimentos em peso e comprimento e reprodução dentro de padrões normais. As águas dos viveiros pesquisados apresentaram de um modo geral condições bióticas e abióticas propícias ao desenvolvimento do microcrustáceo branconeta, D. brasiliensis
Foraging activity rhythms of dinoponera quadriceps (Hymenoptera: formicidae) in its natural environment
(Oxford University Press, 2014) Medeiros, Jeniffer; Azevedo, Dina L. O.; Santana, Melquisedec A. D.; Lopes, Talita R. P.; Araújo, Arrilton
This study characterizes the foraging activity of the queenless ant Dinoponera quadriceps (Kempf) (Hymenoptera: Formicidae) in its natural environment by testing the hypotheses that foraging activity presents both daily and seasonal rhythmic variations, and that these rhythms are related to environmental variables. Four colonies of D. quadriceps were observed in an area of secondary Atlantic forest in northeastern Brazil. Data collection was performed over 72 h every three months during an annual cycle. Both daily and seasonal foraging activity rhythms of D. quadriceps colonies were related to environmental factors, but colony differences also explained part of foraging variations. Foraging activity of D. quadriceps colonies was predominantly diurnal independently of season. In the early dry season, the colonies had two activity peaks, one in the morning and another in the afternoon, with a decrease in foraging at midday; however, during the rest of the year, foraging activity was distributed more evenly throughout the daylight hours. The daily rhythm of foraging activity was likely determined by an endogenous circadian rhythm year-round, but in the dry season, temperature and relative humidity also influenced daily foraging activity, with a negative effect of temperature and a positive effect of relative humidity. On a seasonal scale, foraging activity peaked in the early dry season and suddenly declined at the end of this season, increasing again at the late rainy season. The seasonal rhythm of foraging was negatively related to relative humidity and positively related to prey availability

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