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We consider the problem of radiation from a vertical short (Hertzian) dipole above flat lossy ground, which represents the well-known “Sommerfeld radiation problem” in the literature. The problem is formulated in a novel spectral domain approach, and by inverse three-dimensional Fourier transformation the expressions for the received electric and magnetic (EM) field in the physical space are derived as one-dimensional integrals over the radial component of wavevector, in cylindrical coordinates. This formulation appears to have inherent advantages over the classical formulation by Sommerfeld, performed in the spatial domain, since it avoids the use of the so-called Hertz potential and its subsequent differentiation for the calculation of the received EM field. Subsequent use of the stationary phase method in the high frequency regime yields closed-form analytical solutions for the received EM field vectors, which coincide with the corresponding reflected EM field originating from the image point. In this way, we conclude that the so-called “space wave” in the literature represents the total solution of the Sommerfeld problem in the high frequency regime, in which case the surface wave can be ignored. Finally, numerical results are presented, in comparison with corresponding numerical results based on Norton’s solution of the problem.

People’s estimates are biased toward previously considered numbers (anchoring). We have aggregated all available data from anchoring studies that included at least two anchors into one large dataset. Data were standardized to comprise one estimate per row, coded according to a wide range of variables, and are available for download and analyses online (https://metaanalyses.shinyapps.io/OpAQ/). Because the dataset includes both original and meta-data it allows for fine-grained analyses (e.g., correlations of estimates for different tasks) but also for meta-analyses (e.g., effect sizes for anchoring effects).

Introduction There is growing concern about how people with eating disorders are impacted by the widespread societal restructuring during the COVID-19 crisis. Objectives We aimed to examine how factors relating to the impact of the pandemic associate with eating disorders and quantify this relationship while adjusting for concurrent and longitudinal parameters of risk. Methods We gathered demographic, behavioral and clinical data pre- and mid-pandemic as well as childhood trauma history from a longitudinal online survey of 489 adults (mean age 23.4 years) recruited from the Neuroscience in Psychiatry Network (NSPN). Using pre-pandemic (T1) and concurrent (T2) data we aimed to predict eating disorders at mid-pandemic (T2). We deployed hierarchical generalized logistic regression to ascertain the strength of longitudinal and concurrent associations. Results Pre-pandemic eating disorder scores strongly associated with concurrent eating disorder (z=5.93). More conflict at home mid-pandemic (z=2.03), pre- (lower sensation seeking z=-2.58) and mid-pandemic (higher lack of perseverance z=2.33) impulsivity traits also associated with mid-pandemic eating disorder. Significant correlations between pandemic-related disrupted lifestyle and eating disorder psychopathology both pre- and mid-pandemic were observed. Conclusions Conflict at home mid-pandemic and specific aspects of impulsiveness significantly associated with concurrent eating disorder when adjusted for pre-pandemic eating disorder symptoms, baseline demographics, behavioral traits, history of traumatic experiences and concurrent psychopathology. These results provide insight into the struggles of those suffering with eating disorders during the COVID-19 pandemic and highlight the importance of impulsiveness traits and the immediate family environment in their experience of illness during the pandemic. Disclosure No significant relationships.

Introduction Eating disorders are widespread illnesses with significant impact. There is growing concern about how those at risk of eating disorders overuse online resources to their detriment. Objectives We present systematically gathered and pooled quantitative evidence from our review and meta-analysis study which aimed to provide a quantitative synthesis of all available data linking problematic usage of the internet (PIU) and eating disorder and related psychopathology. We synthesize how PUI influences eating disorder and related psychopathology, and examine what the moderating parameters influencing this relationship are. Methods Our systematic review and meta-analysis protocol was pre-registered electronically in PROSPERO international register and included case-control studies using correlational statistics of association between internet use (various facets) and eating disorder psychopathology. Experimental and prospective studies are systematically reviewed separately. Results The meta-analysis comprised n=32,295 participants, in which PUI was correlated with significant eating disorder general psychopathology Pearson r=0.22 (s.e.=0.04, p

Introduction The Coronavirus pandemic has originated unprecedented sanitary control measures that have conditioned people’s lifestyles and habits. Little is known about the impact of such measures, especially the most restrictive, on recent and growing phenomena such as exercise addiction, use of enhancement drugs, and Body Dysmorphic Disorder (BDD). Objectives The objective was to investigate the above-mentioned phenomena during COVID-19 pandemic and how they relate. Methods The sample consisted of 3161 participants (65% women), from Portugal (11%), Italy (41%), Spain (16%), the UK (12%), Lithuania (12%), Japan (6%), and Hungary (4%). Mean age was 35.05 (SD = 12.10). Participants responded online to the Exercise Addiction Inventory (EAI), the Appearance Anxiety Inventory (AAI), and questions about use of enhancement drugs. Results 4.3% of the participants scored above the cut-off point of the EAI, with higher values registered in the UK and Spain. Exercise addiction was higher among men. Appearance anxiety and body satisfaction problems were found in participants of all participating countries, with 15.2% scoring over the cut-off point for BDD. Higher numbers of those at risk of BDD were found in Italy, Japan, and Portugal. About 29% reported the use of fitness supplements to make them look better, with 6.4% starting a new use during the lockdown. Change in supplements use and exercise are predicted by EAI scores. Change in mental health is predicted by AAI scores. Conclusions This study helps to shed light on how COVID-19 lookdown induced behavioral changes and how they affect physical and mental health-related aspects in different countries.