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Introduction: Physical activity (PA) and sleep disturbances (SD) are related with depressive symptoms in adults. However, evidence that PA and SD are prospectively associated with depression is mixed. The aim of this study was to examine longitudinal and bidirectional associations between PA, SD and depressive symptoms in adolescent girls., Methods: A 2-year longitudinal study was conducted consisting of three waves, each separated by 1 year. The participants were 173 Estonian adolescent girls aged 14.3 ± 0.4 years (M±SD) who individually completed self-report measures of PA, SD and depressive symptoms., Results: Latent growth modelling indicated that the increase in depressive symptoms was associated with an increase in SD and a decrease in PA. Baseline levels of depressive symptoms were predictive of changes in PA and SD, but not the other way around. Moreover, initial SD predicted decrease in PA., Conclusions: High levels of depressive symptoms at baseline were associated with lower PA and higher SD after two years but not vice versa in adolescent girls., (Copyright © 2019. Published by Elsevier Ltd.)

Background: To examine longitudinal associations between sedentary behavior and depressive symptoms among adolescent girls., Methods: A 6-year longitudinal study was conducted consisting of 3 waves, each separated by 3 years. Participants' (n = 249, mean age 12.1 y at baseline) sedentary behaviors were registered using ecological momentary assessment and girls completed the Center for Epidemiological Studies Depression scale. Structural equation modeling of cross-lagged panel models was used to test longitudinal and bidirectional associations., Results: The findings showed that the autoregressive effects were stable for sedentary behavior and depressive symptoms. The cross-lagged effects indicated that the depressive symptoms positively predicted sedentary behavior from early to late adolescence. However, sedentary behavior did not predict depressive symptoms across adolescence., Conclusions: This study shows 1-directional long-term effect of depressive symptoms on sedentary behavior in adolescent girls. Future research on longitudinal relationships between sedentary behavior and depressive symptoms among children and adolescents are needed.

Microgrids comprising renewable energy technologies are often modelled and optimised from a theoretical point of view. Verification of theoretical systems with data of actually implemented systems in the field rarely occurs in an open manner, especially on the intermediate scale of research buildings. To enable modelling of the actual microgrid performance of a research environment, we present a multiyear dataset of a microgrid with solar arrays and a battery. The main energy datasets comprise data per second supplemented by hourly solar irradiation data. These may be combined with data concerning the hourly electricity prices from the main grid and the low-electricity-price periods of national holidays. The level of detail of the data per second in combination with the hourly data in these datasets allows for a comparison to the efficiency and weather-parameter correlation of other renewable energy technologies, as well as forecasting future energy generation and consumption.

This study tested the reciprocal associations between mental toughness (MT) and sport-specific practice (SSP) among 163 adolescent Estonian volleyball players who completed self-reported measures of MT and SSP within a 2-year, three-wave longitudinal research design. Higher MT was associated with higher SSP hours at baseline, and changes in MT and SSP were also significantly interrelated across data from both males and females. These findings have implications for the importance of SSP to increase MT, though future research should replicate this study with other participant samples.

The present study sought to extend existing literature by examining the longitudinal relationships between perfectionistic strivings, autonomous motivation, and engagement in sport-specific activities among youth athletes in three team sports. Participants were 172 team sports athletes (mean age = 15.2 years, SD = 0.5; males = 94, females = 78) who completed measures of perfectionistic strivings and autonomous motivation at the start and end of a competitive season. Players also completed a training diary during the season. Cross-lagged path analysis, found a reciprocal and positive relationship between autonomous motivation and engagement in sport-specific activities. In addition, higher perfectionistic strivings at the start of a competitive season were positively associated with engagement in sport-specific activities at the end of season and not the reverse. Autonomous motivation mediated this relationship between perfectionistic strivings and sport-specific activities engagement. Thus, this study supports the reciprocal association between motivation and engagement in sport-specific activities and unidirectional relations between perfectionistic strivings and sport-specific activities engagement among youth team sports athletes.

Adverse events associated with second-line drugs have been mentioned as obstacles in the management of multidrug-resistant tuberculosis (MDR-TB). Data on adverse events were collected from five DOTS-Plus sites in Estonia, Latvia, Peru (Lima), the Philippines (Manila) and the Russian Federation (Tomsk Oblast). The results show that among 818 patients enrolled on MDR-TB treatment only 2% of patients stopped treatment, but 30% required removal of the suspected drug(s) from the regimen due to adverse events. The study shows that adverse events are manageable in the treatment of MDR-TB in resource-limited settings provided that standard management strategies are applied.

In the rat, reproduction and sexual behavior are controlled by the gonadal steroid regulation of synaptic interactions within the sexually dimorphic limbic-hypothalamic system. The effects of estrogen on the ventromedial nucleus of the hypothalamus, one nucleus within the circuit, are central to the modulation of this behavior. Involvement of the neuropeptide substance P, a member of the tachykinin family of neuropeptides, has been implicated in the regulation of both lordosis behavior and gonadotropin release. However, previous studies have provided conflicting evidence as to whether levels of substance P in the ventromedial nucleus of the hypothalamus are modulated by circulating estrogens. To study this question further, in situ hybridization histochemistry was used to examine levels of beta-preprotachykinin mRNA, which encodes substance P and other tachykinins, in the ventrolateral subdivision of the ventromedial hypothalamus at 10 consecutive timepoints over a 4 day period subsequent to an acute administration of estrogen. Following estrogen treatment, beta-preprotachykinin mRNA expression was increased in cells of the ventrolateral portion of the ventromedial nucleus of the hypothalamus which constitutively express beta-preprotachykinin mRNA; however, there were no statistically significant changes in the number of cells that express detectable levels of beta-preprotachykinin mRNA in the ventrolateral portion of the ventromedial nucleus. Estrogen treatment produced two peaks of beta-preprotachykinin mRNA expression, the first at 2 h and the second at 48 h after the injection of estrogen. These data indicate that estrogen has both rapid and prolonged effects on beta-preprotachykinin mRNA levels, suggesting that estrogen may affect different cellular mechanisms relevant to the induction of beta-preprotachykinin mRNA expression.

Two experiments examined the effects of session duration on responding during simple variable-interval schedules. In Experiment 1, rats were exposed to a series of simple variable-interval schedules differing in both session duration (10 min or 30 min) and scheduled reinforcement rate (7.5 s, 15 s, 30 s, and 480 s). The functions relating response rate to reinforcement rate were predominantly monotonic for the short (10-min) sessions but were predominantly bitonic for the long (30-min) sessions, when data from the entire session were considered. Examination of responding within sessions suggested that differences in the whole-session data were produced by a combination of prospective processes (i.e., processes based on events scheduled to occur later in the session) and retrospective processes (i.e., processes based on events that had already occurred in the session). In Experiment 2, rats were exposed to a modified discrimination procedure in which pellet flavor (standard or banana) predicted session duration (10 min or 30 min). All rats came to respond faster during the short (10-min) sessions than during the first 10 min of the long sessions. As in Experiment 1, the results seemed to reflect the simultaneous operation of both prospective and retrospective processes. The results shed light on the recent controversy over the form of the variable-interval response function by identifying one variable (session duration) and two types of processes (prospective and retrospective) that influence responding on these schedules.

Recently we described the cloning of the gene coding for a Mr 87,000 glucose dehydrogenase (GDH-A) from Acinetobacter calcoaceticus. In this report we describe the cloning of a gene coding for a second GDH (GDH-B) with a Mr of 50,000 from the same organism. This gene was isolated using a 20-mer synthetic oligonucleotide, derived from the N-terminal amino acid sequence of purified GDH-B as a probe to screen a genomic bank. From the DNA sequence of the gdhB gene, a protein can be derived of Mr 52,772 with a 24 amino acid signal peptide which is removed, resulting in the mature protein with a Mr 50,231. In vitro transcription-translation of the gdhB clone shows the mature and the precursor protein. The derived amino acid sequence has no obvious homology with GDH-A of A. calcoaceticus. We show that disaccharides are specific GDH-B substrates and that 2-deoxyglucose is specific for GDH-A.

Glucose dehydrogenase (GDH) is a PQQ dependent bacterial enzyme which converts aldoses to their corresponding acids. A. calcoaceticus contains two different PQQ dependent glucose dehydrogenases designated GDH-A which is active in vivo and GDH-B of which only in vitro activity can be shown. We cloned the genes coding for the two GDH enzymes. The DNA sequences of both gdh genes were determined. There is no obvious homology between gdhA and gdhB. Both GDH enzymes oxidize D-glucose in vitro but disaccharides are specific GDH-B substrates and 2-deoxyglucose is specifically oxidized by GDH-A.