Knowledge gaps remain due to social support measurement heterogeneity and to evidence of reverse causality bias.

Anxiety disorders are the most prevalent mental disorders in developed countries. Obesity is hypothesized to be a risk factor for anxiety disorders but evidence supporting an association between these two conditions is not clear. The objectives of this paper were to systematically review the literature for a link between obesity and anxiety disorders in the general population, and to present a pooled estimate of association. We performed a systematic search for epidemiological articles reporting on obesity (explanatory variable) and anxiety disorders (outcome variable) in seven bibliographical databases. Two independent reviewers abstracted the data and assessed study quality. We found 16 studies (2 prospective and 14 cross-sectional) that met the selection criteria. Measures of effect from prospective data were mixed but cross-sectional evidence suggested a positive association between obesity and anxiety. The pooled odds ratio from cross-sectional studies was 1.4 (confidence interval: 1.2-1.6). Subgroup analyses revealed a positive association in men and women. Overall, a moderate level of evidence exists for a positive association between obesity and anxiety disorders. Questions remain regarding the role of obesity severity and subtypes of anxiety disorders. The causal relationship from obesity to anxiety disorders could not be inferred from current data; future etiologic studies are recommended.

ObjectiveTo estimate prevalence of suicidal ideation and suicidal ideation with a plan in each surveyed country and to examine cross-national differences in associated risk factors.MethodsWe analysed data of students aged 13–17 years who participated in the 2003–2012 Global School-based Health Surveys in 32 countries, of which 29 are low- and middle-income. We used random effects meta-analysis to generate regional and overall pooled estimates. Multivariable logistic regression was used to estimate risk ratios for the associated risk factors. Population attributable fractions were estimated based on adjusted risk ratios and the prevalence of the determinants within each exposure level.FindingsAcross all countries, the pooled 12-month prevalence of suicide ideation were 16.2% (95% confidence interval, CI: 15.6 to 16.7) among females and 12.2% (95% CI: 11.7 to 12.7) among males and ideation with a plan were 8.3% (95% CI: 7.9 to 8.7) among females and 5.8% (95% CI: 5.5 to 6.1) among males. Suicide ideation in the WHO Region of the Americas was higher in females than males, with an estimated prevalence ratio of 1.70 (95% CI: 1.60 to 1.81), while this ratio was 1.04 (95% CI: 0.98 to 1.10) in the WHO African Region. Factors associated with suicidal ideation in most countries included experiences of bullying and physical violence, loneliness, limited parental support and alcohol and tobacco use.ConclusionThe prevalence of adolescent suicidal behaviours varies across countries, yet a consistent set of risk factors of suicidal behaviours emerged across all regions and most countries.

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A beam with an angular-dependant phase Φ = ℓϕ about the beam axis carries an orbital angular momentum of ℓℏ per photon. Such beams are exploited to provide superresolution in microscopy. Creating extreme ultraviolet or soft-x-ray beams with controllable orbital angular momentum is a critical step towards extending superresolution to much higher spatial resolution. We show that orbital angular momentum is conserved during high-harmonic generation. Experimentally, we use a fundamental beam with |ℓ| = 1 and interferometrically determine that the harmonics each have orbital angular momentum equal to their harmonic number. Theoretically, we show how any small value of orbital angular momentum can be coupled to any harmonic in a controlled manner. Our results open a route to microscopy on the molecular, or even submolecular, scale.

The ability to record images with extreme temporal resolution enables a diverse range of applications, such as fluorescence lifetime imaging, time-of-flight depth imaging and characterization of ultrafast processes. Recently, ultrafast imaging schemes have emerged, which require either long acquisition times or raster scanning and have a requirement for sufficient signal that can only be achieved when light is reflected off an object or diffused by a strongly scattering medium. Here we present a demonstration of the potential of single-photon detector arrays for visualization and rapid characterization of events evolving on picosecond time scales. The single-photon sensitivity, temporal resolution and full-field imaging capability enables the observation of light-in-flight in air, as well as the measurement of laser-induced plasma formation and dynamics in its natural environment. The extreme sensitivity and short acquisition times pave the way for real-time imaging of ultrafast processes or visualization and tracking of objects hidden from view.

The ability to detect motion and track a moving object hidden around a corner or behind a wall provides a crucial advantage when physically going around the obstacle is impossible or dangerous. Previous methods have demonstrated that is possible to reconstruct the shape of an object hidden from view. However, these methods do not enable the tracking of movement in real-time. We demonstrate a compact non-line-of-sight laser ranging technology that relies upon the ability to send light around an obstacle using a scattering floor and to detect the return signal from a hidden object with only a few seconds acquisition time. By detecting this signal with a single-photon avalanche diode (SPAD) camera, we follow the movement of an object located a meter away from the camera with centimetre precision. We discuss the possibility of applying this technology to a variety of real-life situations in the 1 near future.Recent years have seen remarkable advances in the field of image processing and data acquisition, allowing for a range of novel applications [1][2][3][4][5][6][7][8]. An exciting new avenue is using optical imaging techniques to observe and track objects that are both in movement and hidden from the direct line-of-sight. The ability to detect motion and track a moving object hidden from view would provide a crucial advantage when physically going around the obstacle is impossible or dangerous, for example to detect a person moving behind a wall or a car approaching from behind a blind corner.Techniques for imaging static objects that are hidden from view have been recently demonstrated relying on, for example, radar technology [9,10], variations of laser illuminated detection and ranging (LIDAR) [3,5,11,12], or speckle-based imaging. The latter approach was first developed for imaging through opaque barriers [13][14][15], and also allows for imaging around corners [16,17]. The work of Velten et al. [5] and, more recently, Buttafava et al. [8] sets out to establish the 3D shape of a static hidden object by collecting the return scattered light with a streak camera or single-photon avalanche diode, respectively. While remarkable 3D reconstruction of objects are achieved with these techniques, Buttafava et al. point out that the requirement for scanning and subsequent long acquisition times mean that their technique is currently unsuitable for imaging moving objects.Notwithstanding these ingenious imaging systems, locating the position of a hidden object in motion and monitoring its movement in real time remains to date a major challenge. We set out to solve the tracking problem and develop a technique based on both hardware and software implementations that are specifically designed for this 2 purpose. Our solution is based on a LIDAR-like approach where a single-photon avalanche diode (SPAD) camera [7,[18][19][20][21][22] is used to image light that is backscattered from beyond the direct line-of-sight (see Methods for camera details). The high temporal resolution of the camera relies on the fact that each indiv...

Negative symptoms observed in patients with psychotic disorders undermine quality of life and functioning. Antipsychotic medications have a limited impact. Psychological and psychosocial interventions, with medication, are recommended. However, evidence for the effectiveness of specific non-biological interventions warrants detailed examination.To conduct a meta-analytic and systematic review of the literature on the effectiveness of non-biological treatments for negative symptoms in psychotic disorders.We searched for randomised controlled studies of psychological and psychosocial interventions in psychotic disorders that reported outcome on negative symptoms. Standardised mean differences (SMDs) in values of negative symptoms at the end of treatment were calculated across study domains as the main outcome measure.A total of 95 studies met our criteria and 72 had complete quantitative data. Compared with treatment as usual cognitive-behavioural therapy (pooled SMD -0.34, 95% CI -0.55 to -0.12), skills-based training (pooled SMD -0.44, 95% CI -0.77 to -0.10), exercise (pooled SMD -0.36, 95% CI -0.71 to -0.01), and music treatments (pooled SMD -0.58, 95% CI -0.82 to -0.33) provide significant benefit. Integrated treatment models are effective for early psychosis (SMD -0.38, 95% CI -0.53 to -0.22) as long as the patients remain in treatment. Overall quality of evidence was moderate with a high level of heterogeneity.Specific psychological and psychosocial interventions have utility in ameliorating negative symptoms in psychosis and should be included in the treatment of negative symptoms. However, more effective treatments for negative symptoms need to be developed.