dataesr/scientific-paragraphs-categorization huggingface dataset:
Data with periods of continuous zero values for more than 20 min were considered 'accelerometer non-wear' periods and were therefore excluded from the analyses. Likewise, registers of more than 20 000 counts per minute were interpreted as a potential malfunction of the accelerometer and were also excluded from the analyses. Data were considered valid if the adolescents had accelerometer counts for at least 3 d with at least 8 h of recording time per day  (19). Physical activity variables included in the present study were: sedentary time and moderate-to-vigorous physical activity (MVPA) in minutes per day (min/d) and total physical activity in counts per minute (cpm). Sedentary time and MVPA were calculated according to the standardized cut-off point of ,100 and $2000 cpm, respectively  (19, 20).
MVPA was dichotomized into ,60 min/d (not meeting the physical activity recommendation) and $60 min/d (meeting the recommendation) according to the WHO guidelines  (21). Patterns of physical activity were also self-reported using the International Physical Activity Questionnaire for Adolescents (IPAQ-A)  (22). IPAQ-A covers four domains of physical activity: (i) school-related physical activity (including activity during physical education classes and breaks); (ii) transportation; (iii) housework; and (iv) activities during leisure time. In each of the four domains, the time periods per day (and the numbers of days per week) involved in activities were recorded. Data were cleaned and truncated  (23)  and afterwards classified into light (i. e. walking), moderate and vigorous activity according to the guidelines for data processing and analyses of IPAQ (http://www.
Data analyses We studied the association of breakfast consumption (i. e. consumer, occasional consumer and skipper) with physical activity, sedentary time and physical fitness using multilevel analysis. Breakfast consumption was entered in the analysis as the independent variable, with physical activity, sedentary time and physical fitness components as dependent variables, and centre (random intercept), age, parent's education as well as family affluence as covariates. All analyses were performed with the two different methods to assess breakfast patterns, (i) the computer-based tool for 24 h recalls and (ii) the 'Food Choices and Preferences' questionnaire, and with measured and self-reported physical activity, sedentary time and physical fitness. The level of statistical significance was controlled for multiple testing (0?05/number of tests 5 0?05/10 5 0?005); therefore, results were considered statistically significant when P # 0?005.
Similar results were observed when cardiorespiratory fitness was self-reported (with a borderline difference of P 5 0?006). The results persisted when breakfast consumption was assessed with the 'Food Choices and Preferences' questionnaire (Fig. 1 ). However, both in males and females no differences were observed across breakfast consumption categories (assessed by 24 h recall or the 'Food Choices and Preferences' questionnaire) and mean estimates of measured and self-reported muscular fitness and speed/agility after adjusting for multiple comparisons (Table  2 ). Finally, the odds ratios and 95 % confidence intervals for meeting the physical activity recommendations and having high cardiorespiratory fitness according to breakfast consumption categories were calculated. Breakfast consumption was not associated with meeting the physical activity recommendations, either measured or self-reported, with no difference when using both methods to assess the breakfast patterns (data not shown).
The different methodology used to assess physical activity may explain differences among our findings and those previously observed. Our data concur with those that assessed physical activity objectively  (5). To the best of our knowledge, the present study is the first to explore the association between breakfast consumption and physical activity assessed by two validated methods, accelerometry and IPAQ-A, in the same report. On the other hand, although some associations between breakfast consumption and sedentary time were detected for males and females, the present study does not provide strong evidence that breakfast consumption was related to sedentary time because the results were not consistent across methods or gender. In addition, we have not found previous studies analysing the association between breakfast habits and sedentary time, which hampers further comparisons.
In the present study, we confirmed that male occasional consumers and breakfast skippers had lower levels of cardiorespiratory fitness than breakfast consumers. We added new data that showed similar results using a validated tool to assess self-reported cardiorespiratory fitness, the IFIS  (13). Moreover, we observed that male and female breakfast skippers were less likely to have high cardiorespiratory fitness, both objectively measured and self-reported, than breakfast consumers. Similar results were observed by Sandercock et al. (6)  , although the authors failed to take into account the socio-economic status (e. g. educational level of parents and family affluence) as a potential confounder, which has been associated with breakfast consumption  (2, 32). In addition, we were the first to study other components of physical fitness, muscular fitness and speed/agility.
Acknowledgements Sources of funding: The HELENA Study took place with the financial support of the  European Community Sixth RTD Framework Programme  (Contract FOOD-CT:  2005-007034 ). This work was also partially supported by the  European Union , in the framework of the  Public Health Programme  ( ALPHA  project, ref. 2006120); the  Swedish Council for Working Life and Social Research (FAS) ; the  Spanish Ministry of Education  (grant nos. AP-2008-03806 ,  RYC-2010-05957 ,  RYC-2011-0901 ); the  Spanish Ministry of Health , Maternal,  Child Health and Development Network  (grant no. RD08/0072  to L. A. M. ); the  Universidad Politecnica of Madrid  (grant no. CH/018/ 2008 ); and the  Swedish Heart-Lung Foundation  (grant no. 20090635 ). The contents of this paper reflect only the views of the authors and the rest of the HELENA Study Group members, and the  European Community  is not liable for any use that may be made of the information contained herein.
Ultrasonic vocalization recording In all experiments, except olfaction tests, a condenser ultrasound microphone Polaroid/CMPA was placed above the experimental chamber, high enough so that the receiving angle of the microphone covered the whole area of the test cage. For the 3Ch condition, one microphone was placed above each side chamber with an angle allowing full chamber coverage but avoiding any recording from the opposite chamber (Figure  1 ). Microphones were connected to an ultrasound recording interface Ultrasound Gate 416 H, which was itself plugged into a personal computer equipped with the recording software Avisoft Recorder USG (Sampling frequency: 250 kHz; FFT-length: 1024 points; 16-bits). All recording hardware and software were from Avisoft Bioacoustics® (Berlin, Germany).
STATISTICAL ANALYSES Statistical analyses were made with Statview® software. ANOVArepeated measures were used to compare the reward factors two by two (Social vs. Food, Social vs. Object, and Food vs. Object). Repeated measures ANOVA were used to compare subject performances. Post-hoc analyses were performed using Wilcoxon signed-rank (for dependent variables) or Mann-Whitney (for independent variables) non parametric tests only when appropriate. Correlation data were analyzed with a Spearman correlation test between behavioral measures and number of calls. The significance threshold was set at p < 0. 05. For all post-hoc paired comparisons a Bonferroni correction was applied (α = α/k; where α is significance threshold and k the number of comparisons).
, 2011) , the current data may suggest that for β2 -/-mice, food can be considered as an interesting novel object, when the food motivation is low. The number of USVs emitted was significantly higher when mice faced the social reward than when they faced any of the two other rewards. This was true for both WT and β2 -/-mice. If this measure obviously increased when having two mice instead of one, it also confirmed the stimulating effect of the social context on USV's emission  (Vignal et al. , 2005; Arriaga et al. , 2012; Chabout et al. , 2012). It is interesting to note that having two mice instead of one did not simply multiply by two the number of USVs. Indeed, comparing the number of USVs in the 3Ch (social condition) and in the SIT, two experimental conditions in which a dyad of mice was recorded, clearly showed that the number of animals was not a critical factor.
EXPERIMENTAL PROCEDURE Subjects were seated in a chair in front of a computer in a quiet, dim room. Each participant was subjected to a memory encoding task while their PFC activation was monitored using fNIRS neuroimaging and then behaviorally tested in a retrieval task. After the eight fNIRS probe-set was adjusted on the forehead scalp overlaying the DLPFC (see fNIRS section below for a description) and the in-ear headphones inserted, subjects were informed that they would be presented with different lists of words with two different auditory contexts: music or silence. They were asked to memorize both the lists of words and the context in which words were encoded. Verbal stimuli consisted of 42 taxonomically unrelated concrete nouns selected from the French "Lexique" database  (New et al.
fNIRS MEASUREMENTS An eight-channel fNIRS system (Oxymon MkIII, Artinis Medical Systems B. V. , The Netherlands) was used to measure the concentration changes of O 2 Hb and HHb (expressed in micromoles) using an age-dependent constant differential path-length factor given by 4. 99 + 0. 0067*(age 0. 814;  Duncan et al. , 1996). Data was acquired at a sampling frequency of 10 Hz. The eight fNIRS optodes (four emitters and four detectors) were placed symmetrically over the dorsal part of the PFC (Brodmann Areas 46 and 9, EEG electrodes AF7/8, F5/6, F3/4, and AF3/4 of the international 10/10 system;  Okamoto et al. , 2004; Jurcak et al. , 2007) , and the distance between each emitter and detector was fixed to 3. 5 cm (Figure  2 ). To optimize signal-to-noise ratio during the fNIRS recording, the eight optodes were masked from ambient light by a black plastic cap that was kept in contact with the scalp with elastic straps, and all cables were suspended from the ceiling to minimize movement artifacts  (Cui et al.
Behavioral data Each subject's item-and source-memory accuracy (hit) rates (number of hits for each condition during the yes/no recognition) as well as false alarms were calculated for both the silence and music conditions. To examine source memory, we analyzed the proportion of correct source judgments among item-memory hits. A paired t-test was used to compare the item-and source-memory scores between the silence and music conditions. One sample t-tests were used to ascertain that all the scores were significantly above chance.
BDNF expression assessment In situ hybridization was done using a 1085 bp probe based on the rat BDNF gene (accession number NM_012513). The probe was labelled with [ 35 S]UTP, purified and used at 350 pM. Cryostat (Microm, France) frontal sections (20 mm) were fixed, acetylated, dehydrated and de-fatted prior to hybridization with the probe in hybridization buffer at 54 xC overnight. Sections were then washed, fixed, treated with RNase and dehydrated, left to dry, then exposed to BioMax MR films for 6 d.
Local BDNF deletion The placement and extent of the AAV injections were assessed by the presence of eGFP-positive neurons for both control (eGFP alone) and BDNF-deleted animals (eGFP-Cre fusion). eGFP labelling had to be present and concentrated in the lateral PB for the injection placement to be considered as valid, although it often also included labelling spreading into the median PB. The pontine PB was the main targeted area, but some injections displayed a larger rostro-caudal spread, thereby also including the mesencephalic PB (Fig. 2 a, b, d ). eGFP expressing neurons were often clustered in the external aspect of PB, namely, the external lateral, lateral crescent and external medial nuclei. Animals were included for data analysis if the viral infection comprised the lateral PB, remained within the boundaries of the PB and was validated bilaterally.
2009; Seiler et al. 2007; Telford et al. 1988 ) and no previous study analysed temporal trends in freestyle swimming for all official race distances on both short and long courses. The present study used annual results of national (i. e. Swiss) swimmers and bi-annual results of international (i. e. finalists in FINA World Championships) swimmers. Since women do not compete in FINA World Championships of 1,500 m distance on short courses, we compared data of national and international swimmers. The aims of the study were to investigate (i) the effects of course length on freestyle swimming speed for both men and women at national and international level and (ii) the changes in freestyle swimming speed during the 2000-2012 period. We hypothesized that (i) swimming speed would be faster on short course than on long course for both sexes and (ii) swimming speeds would increase over time for both short-and long-course at both national and international level.
Samples and sources All procedures used in the study met the ethical standards of the Swiss Academy of Medical Sciences (www. samw. ch/en/Ethics/Guidelines/Currently-valid-guidelines. html) and were approved by the Institutional Review Board of Kanton St. Gallen, Switzerland with a waiver of the requirement for informed consent of the participants given the fact that the study involved the analysis of publicly available data. Annual top ten results of freestyle swimmers at national level for all freestyle events on 25 m and 50 m courses were analyzed for men and women from the Swiss high score list and bi-annual results of freestyle finalists in the FINA World Swimming Championships for swimmers at international level during the 2000-2012 period. The data for national swimmers were obtained from the Swiss Swimming Federation (http://rankings.
e. cluster) of identical athletes. Regression analyses of performance were further corrected for age of athletes to prevent a misinterpretation of 'age-effect' with 'time-effect' by adding the age of an athlete as a correction factor to Model 2 (Model 3). Student's t-test was used to determine the significance of differences between the performance in long and short course. One-way analysis of variance (ANOVA) with subsequent Dunnett post-hoc analysis was used to determine the significance of differences between more than two groups. A two-way-ANOVA was used to examine the interactive effect of sex and course length on performance. Statistical analyses were performed using IBM SPSS Statistics (Version 19, IBM SPSS, Chicago, IL, USA) and GraphPad Prism (Version 5, GraphPad Software, La Jolla, CA, USA).
There is no data for race distance of 1,500 m at international competition level, as  women do not compete in FINA World Championships at this particular race distance on short courses. Swimming speed consistently decreased with increasing race distance, and men were faster than women (Figures  1, 2, 3  and 4 ). Temporal changes in swimming speed and sex-related differences on short and long courses Men and women finalists in FINA World Championships showed significant improvements in swimming speed from 2000 to 2012 in both short and long course and over all distances (Figures  1  and 2 , Tables  3  and 4 ). Male national swimmers were also able to improve performance during this period on short and long course events, except for short course events on longer distances (800 and 1500 m; Figures  3  and 4 , Tables  5  and 6 ).
Methods Data are from the 1958 National Child Development Study (NCDS) which included all live births during 1 week in 1958 (n = 18,555) in Great Britain. Subsequent data collections (sweeps) were carried out on cohort members aged  7, 11, 16, 23, 33, 42, 46  and 50. At the last sweep, carried out in 2008, 9,790 individuals participated in the selfreported questionnaire and face to face interview, representing 53 % of the original sample. The NCDS has been described in detail elsewhere  [13]. Follow-up has been good over time, 84 % participated at the age of 16, with a gradual dwindling in participation throughout adulthood (72 % at age 23, and 65 % at age 42) when participants were most likely to have moved  [13]. Refusal rates have been low, with 7 % at age 23 and 13 % at age 42 for example  [13].
Adverse childhood experiences (ACE) In this study we have identified ACE as a set of traumatic and stressful psychosocial conditions that are out of the child's control, that tend to co-occur  [14]  and often persist over time  [15, 16]. Our definition of ACE is: intra-familial events or conditions causing chronic stress responses in the child's immediate environment. These include notions of maltreatment and deviation from societal norms, where possible to be distinguished from conditions in the socioeconomic and material environment. The NCDS has an immense wealth of prospectively collected data. ACE have already been extracted from these datasets and used to examine their impact on psychopathology  [15, 17]. There are many ways in which the adversity can be conceptualised, including financial difficulties, family dissention, and child physical or sexual abuse.
Here, we have attempted to construct a theoretical framework to define ACE prior to extracting any data. Our definition has been influenced by previous epidemiological studies of ACE, notably the San Diego study  [18]  the Australian study  [14] , other more general studies related to adversity  [19, 20]  as well as discussions on ACE by a WHO expert committee  [21]  in 2009. Information was extracted on events and conditions that corresponded with the above definition and previous literature from the NCDS datasets. Data were collected in childhood at 7, 11 and 16 years of age from questions posed to the child's parent or their teacher. Sources of adversity were divided into six categories: Exposure to adversity was identified by a positive response to any of the above categories. Respondents were excluded if they had missing data for all six categories.
All-cause premature mortality Deaths were ascertained systematically through receipt of death certificates to the Centre for Longitudinal Studies from the National Health Service Central Register. The mortality data currently available to researchers provided information on date-of-death up to December 2008. Since information on death was obtained from the register, even when individuals were lost to follow-up in the cohort, information on their death will have been received. The baseline sample includes participants who were alive from 16 years (1974).
As the cohort ages, and their cause-specific mortality becomes driven to a larger extent by chronic diseases, lifestyle factors and behaviours is likely to explain more of observed differences in mortality. This study has a number of limitations. Attrition is a problem in cohort studies, increasing the potential for selection bias in the remaining sample. In this study up to 30 % missing data was present among the adult variables collected at the age of 23. We dealt with this by imputing the missing data in the eligible sample, thereby adjusting the data for selection bias taking the missing at random (MAR) assumption. We consider this assumption to be reasonable because it allows missingness to depend on observed data, such as baseline characteristics and other measures occurring at different time points  [25].
However, the assumption of MAR is unverifiable and we cannot rule-out that some data are 'missing not at random' (MNAR). Multiple imputation models, such as the one used on these data, include large numbers of covariates, helping to render the MAR assumption more plausible and to limit the impact of MNAR missingness  [26]. Another limitation in this study relates to the choice of adult mediating variables at 23 years. Adult behavioural variables were collected subsequently at ages 33, 41, and 46. In order to simplify our analytic approach, we chose to use early adult variables as proxy indicators of behaviours typology, and mental health state, bearing in mind that the outcome of interest was mortality before \50 years. At present, cause-specific mortality linked with the cohort is unavailable.
Acknowledgments We are grateful to the  Centre for Longitudinal Studies (CLS), Institute of Education  for the use of the NCDS data and to the  Economic and Social Data Service (ESDS)  for making them available. However, neither CLS nor ESDS bear any responsibility for the analysis or interpretation of these data. MKI's fellowship is funded by  La Ligue  nationale contre le cancer. This work was also funded by the  Institut National du Cancer  & the Institut de recherche en santepublique.
Background: University students face multiple stressors such as academic overload, constant pressure to succeed, competition with peers as well as concerns about the future. Stress should not be considered on its own, but should be associated with potential risk behaviors leading to onset of substance use and related problems heightened during the university period. The aim of this study was to determine the prevalence of main substance use and behavioral addictions among students in higher education in France and to examine the relationship with perceived stress. Methods: A self-administered questionnaire was filled out by university student volunteers from Upper Normandy (France) either by anonymous online questionnaire or by paper questionnaire. Data collected included socioeconomic characteristics, Perceived Stress Scale (PSS), substance use (tobacco, alcohol, and cannabis) and hazardous behaviors: alcohol abuse problems, smoking, consumption of cannabis, eating disorders, and cyber addiction.
Data collection The self-questionnaire was anonymous and included socioeconomic characteristics (age, gender, size, weight, grant holder status, student job status, lifestyle), regular practice of a sport, substance use and disorders (tobacco, alcohol, cannabis, and eating habits), and risk of cyberaddiction and perceived mental stress (Additional file 1). The study was carried out between 2009 and 2011. The universities and schools involved were specialised in various areas: technologist, business, engineering; psychology, sciences, language and sport were regrouped in university; medicine and pharmacy; nursing, physiotherapy, midwifery and radiologic technologist studies were regrouped in para-medic. The questionnaire did not include any information that could be used to identify the students.
Statistical analysis The Chi-square (χ 2 ) test or Fisher's exact test were used for comparisons of qualitative data. Quantitative variables were summarized by means and medians and compared using the Student's t-test. Logistic regression was performed to evaluate the independent determinants of perceived stress. Crude Odds Ratios (OR) and Adjusted Odds Ratios (AOR) and their 95% confidence intervals (CI) were calculated. Factors with a p value lower than 0. 25 were included in the multivariate analysis and p value lower than 0. 05 was considered to be significant. Statistical analysis was conducted using Statview® software package.