University of Crete

About: University of Crete is a education organization based out in Rethymno, Greece. It is known for research contribution in the topics: Population & Galaxy. The organization has 8681 authors who have published 21684 publications receiving 709078 citations. The organization is also known as: Panepistimio Kritis.

Pre-engineered abruptly autofocusing beams

Abstract: We introduce a new family of (2+1)D light beams with pre-engineered abruptly autofocusing properties. These beams have a circularly symmetric input profile that develops outward of a dark disk and oscillates radially as a sublinear-chirp signal, creating a series of concentric intensity rings with gradually decreasing width. The light rays involved in this process form a caustic surface of revolution that bends toward the beam axis at an acceleration rate that is determined by the radial chirp itself. The collapse of the caustic on the axis leads to a large intensity buildup right before the intended focus. This ray-optics interpretation provides valuable insight into the dynamics of abruptly autofocusing waves.

Variables independently associated with self-reported obesity in the European Union

Abstract: ObjectiveThe rapid increase in obesity rates over recent years suggest that cultural and societal influences are affecting the adjustment in the energy balance equation in addition to other physiopathological or genetic determinants. Therefore, a pan-EU study was carried out to explore the influence of sociodemographic factors as well as some attitudes (smoking and exercise) on the prevalence of obesity in the adult population of all 15 member states of the EU.DesignOverall, a sample of 15 239 individuals aged 15 years and upwards in the EU completed the questionnaire. Subject selection was quota-controlled to make the sample nationally representative following a multistage stratified cluster sampling. Self-reported height and weight were used to calculate body mass index (BMI).ResultsFrom the EU average results, it can be seen that only about half of the EU population (48%) is within the normal weight range, while the obesity (BMI > ≥ 30 kg m−2) prevalence was about 10% in the EU and the overweight prevalence was 36.6% and 25.6% among men and women, respectively. UK subjects had the highest prevalence of obesity (12%), while Italians, French and Swedes had the lowest levels of obesity (about 7%). Concerning age and social class interactions, logistic regression analysis showed that high social class and younger individuals in all groups had a lower odds ratio for obesity prevalence. People with a higher level of education are less likely to be obese, while the interaction between educational levels and obesity was different for men and women. A low participation in various leisure-time physical activities, the lack of interest (precontemplation) in being involved in exercise/physical activity and the increasing number of hours sitting down at work appear to be predictors of obesity. Single individuals were less prone to become obese than couples or widowed/divorced people. Finally, smoking status was statistically linked to the prevalence of obesity, since non-smokers or ex-smokers for more than 1 year presented a higher tendency for a BMI > 30.ConclusionsThis survey confirms that a priority area for health intervention aimed at preventing the development of obesity should be to increase levels of physical activity, although the approach will depend on the population, especially with respect to educational and socioeconomic aspects.

The association of spinal osteoarthritis with lumbar lordosis

Abstract: Background: Careful review of published evidence has led to the postulate that the degree of lumbar lordosis may possibly influence the development and progression of spinal osteoarthritis, just as misalignment does in other joints. Spinal degeneration can ensue from the asymmetrical distribution of loads. The resultant lesions lead to a domino- like breakdown of the normal morphology, degenerative instability and deviation from the correct configuration. The aim of this study is to investigate whether a relationship exists between the sagittal alignment of the lumbar spine, as it is expressed by lordosis, and the presence of radiographic osteoarthritis. Methods: 112 female subjects, aged 40-72 years, were examined in the Outpatients Department of the Orthopedics’ Clinic, University Hospital of Heraklion, Crete. Lumbar radiographs were examined on two separate occasions, independently, by two of the authors for the presence of osteoarthritis. Lordosis was measured from the top of L1 to the bottom of L5 as well as from the top of L1 to the top of S1. Furthermore, the angle between the bottom of L5 to the top of S1 was also measured. Results and discussion: 49 women were diagnosed with radiographic osteoarthritis of the lumbar spine, while 63 women had no evidence of osteoarthritis and served as controls. The two groups were matched for age and body build, as it is expressed by BMI. No statistically significant differences were found in the lordotic angles between the two groups Conclusions: There is no difference in lordosis between those affected with lumbar spine osteoarthritis and those who are disease free. It appears that osteoarthritis is not associated with the degree of lumbar lordosis.

Molecular genetic evidence for overlap between general cognitive ability and risk for schizophrenia: A report from the Cognitive Genomics consorTium (COGENT)

Abstract: It has long been recognized that generalized deficits in cognitive ability represent a core component of schizophrenia (SCZ), evident before full illness onset and independent of medication. The possibility of genetic overlap between risk for SCZ and cognitive phenotypes has been suggested by the presence of cognitive deficits in first-degree relatives of patients with SCZ; however, until recently, molecular genetic approaches to test this overlap have been lacking. Within the last few years, large-scale genome-wide association studies (GWAS) of SCZ have demonstrated that a substantial proportion of the heritability of the disorder is explained by a polygenic component consisting of many common single-nucleotide polymorphisms (SNPs) of extremely small effect. Similar results have been reported in GWAS of general cognitive ability. The primary aim of the present study is to provide the first molecular genetic test of the classic endophenotype hypothesis, which states that alleles associated with reduced cognitive ability should also serve to increase risk for SCZ. We tested the endophenotype hypothesis by applying polygenic SNP scores derived from a large-scale cognitive GWAS meta-analysis (~5000 individuals from nine nonclinical cohorts comprising the Cognitive Genomics consorTium (COGENT)) to four SCZ case-control cohorts. As predicted, cases had significantly lower cognitive polygenic scores compared to controls. In parallel, polygenic risk scores for SCZ were associated with lower general cognitive ability. In addition, using our large cognitive meta-analytic data set, we identified nominally significant cognitive associations for several SNPs that have previously been robustly associated with SCZ susceptibility. Results provide molecular confirmation of the genetic overlap between SCZ and general cognitive ability, and may provide additional insight into pathophysiology of the disorder.