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We study geometric structures arising from Hermitian forms on linear spaces over real algebras beyond the division ones. Our focus is on the dual numbers, the split-complex numbers, and the split-quaternions. The corresponding geometric structures are employed to describe the spaces of oriented geodesics in the hyperbolic plane, the Euclidean plane, and the round $2$-sphere. We also introduce a simple and natural geometric transition between these spaces. Finally, we present a projective model for the hyperbolic bidisc, that is, the Riemannian product of two hyperbolic discs., 21 pages, 4 figures

Матеріали Міжнародної науково-практичної конференції "Соціально-економічні виклики" присвячені пошуку системного вирішення мультидисциплінарних проблем в сфері сучасного розвитку, управління, адміністрування різних систем, корпоративної соціальної відповідальності, управління інноваціями в різних сферах навколишнього середовища управління. Для науковців, науковців, студентів, аспірантів, представників бізнесу громадських організацій та вищих навчальних закладів та широкого кола читачів. Материалы Международной научно-практической конференции «Социально-экономические вызовы» посвящены поиску системного решения междисциплинарных проблем в области современной разработки, управления, администрирования различных систем, корпоративной социальной ответственности, управления инновациями в различных областях экологии управления. Для ученых, ученых, студентов, аспирантов, представителей бизнеса, общественных организаций, вузов и широкого круга читателей. Proceedings of the International Scientific and Practical Conference "Socio-Economic Challenges" are devoted to finding a systemic solution to multidisciplinary problems in the field of modern development, management, administration of various systems, corporate social responsibility, innovation management in various fields of environmental management. For scientists, scientists, students, graduate students, representatives of business and public organizations and higher education institutions and a wide range of readers. Виконано в рамках науково-дослідної теми «Механізм синергетичної взаємодії інструментів економічної політики як драйвер стабілізації секторів економіки в контексті зростаючих чинників вразливості внаслідок пандемії COVID-19», що фінансується за рахунок коштів Національного фонду досліджень України, 2020-2021.

OBJECTIVE: To describe the implementation and feasibility of the national healthcare guidelines on childhood obesity in a region with a high prevalence of overweight and obesity in children.DESIGN: Descriptive, implementation study.METHOD: The implementation of the guidelines took place in the borough Amsterdam West. In total, 17 general practitioners (GP) from the Academic General Practice Network (ANH) of the VU University Medical Center, Amsterdam, participated in the study, along with 19 child healthcare practitioners and 3 paediatricians. A number of measures were taken to promote implementation. Feasibility was evaluated using both qualitative and quantitative methods.RESULTS: The participating healthcare providers found the training in application of the guidelines and case study discussions useful. GPs found that their role as central caregiver was not feasible. All participants expressed a preference for child healthcare practitioners as the central caregiver. A total of 327 obese children were invited to attend the GP's surgery; only 65 of them participated in the study and only 28 children were monitored for a whole year. Collaboration agreements between involved healthcare providers were rarely fulfilled.CONCLUSION: Implementation of the national healthcare guidelines on childhood obesity in the current form appears not to be feasible in Amsterdam West, despite the many implementation-enhancing measures that were applied. It is questionable whether the national healthcare guidelines on childhood obesity in its current form can contribute to addressing the societal problem of overweight and obesity in children.

Zelfs in een goed onderzochte insectengroep als de zweefvliegen zijn nog altijd nieuwe soorten voor de Nederlandse fauna te ontdekken. Ook in 2014 was het weer raak, dit keer in het fraaie natuurgebied rond de Drentsche Aa. Het lijkt niet toevallig dat deze aanvulling op de Nederlandse fauna juist hier werd gevonden. Deze vindplaats vult ecologische informatie uit het buitenland aan, waardoor langzamerhand een beeld begint te ontstaan van de levenswijze van deze zeldzame zweefvlieg, waarover tot voor kort weinig bekend was.

De gewone citroenzweefvlieg Xanthogramma pedissequum is een eenvoudig te herkennen zweefvlieg. Tenminste, dat dachten we tot voor kort. Nu blijkt dat de bijna identieke X. dives en X. stackelbergi ook in Nederland rondvliegen. Gelukkig zijn er enkele kenmerken waarmee deze drie soorten citroenzweefvlieg in het veld redelijk herkenbaar blijken. In dit artikel bespreken we deze kenmerken en geven we informatie over verspreiding en vliegtijden van de drie soorten.

The present paper deals with dune dynamics in a zone of the Strait of Dover located in the sea lane running into the North Sea. The dunes, widespread in this 35-m depth area, are mobile sedimentary structures (up to 40 m.yr(-1)) that culminate at a maximum of 22 m depth and endanger navigation as well as submarine man-made structures (cables, pipelines). Single- and multibeam bathymetric data, coupled with seismic data, allow us to follow dune displacements over different time scales. A net bedload parting zone has been displayed and divides the area into two parts, SE and NW. However, according to the considered time-scale, dune movements present Variations in intensity and direction. Over a long-term period (decades), sedimentary dynamics fit the regional scheme of the residual tidal currents that induce transport toward the SW and the NE in the respective SE and NW parts of the studied area. Over a medium-term period (several years), meteorological data show that a high frequency of storm winds alters the residual sand transport characteristics by strengthening, slowing or reversing the effect of the tidal currents and can lead to the reversal of dune asymetry., Cet article traite de la dynamique des dunes de sable dans une zone du détroit du Pas-de-Calais située dans le rail de navigation débouchant en mer du Nord. Les dunes de sable, répandues dans ce secteur, sont des structures sédimentaires mobiles (jusque 40 m·an−1) qui culminent jusqu'à 22 m de profondeur et mettent en danger la navigation ainsi que les ouvrages sous-marins (câbles, pipelines). Les données de bathymétrie mono- et multifaisceaux, couplées aux données de sismique, permettent de suivre les déplacements des dunes à différentes échelles de temps. Une zone de divergence du transport sédimentaire a été mise en évidence et divise la zone en deux secteurs, SE et NW. Toutefois, selon l'échelle de temps considérée, les mouvements dunaires présentent des variations en intensité et en direction. Sur le long terme (à l'échelle de la décennie), la dynamique sédimentaire se calque sur le schéma régional des courants de marée résiduels qui induisent des transports sédimentaires vers le SW et le NE dans les secteurs respectifs SE et NW de la zone d'étude. Sur le moyen terme (à l'échelle de quelques années), les données météorologiques montrent qu'une forte fréquence des vents de tempête peut modifier les caractéristiques du transport résiduel sableux en renforçant, en ralentissant ou en inversant l'effet des courants de marée et peut conduire à l'inversion de l'asymétrie des dunes.

A synthesis of the geology of the Belgian continental shelf is here presented. The main part of this document is dedicated to the review of the lithostratigraphy, geotechnical properties, geometry and distribution of the Tertiary and Quaternary deposits. The data compilation, review and assessment have been conducted from the numerous existing studies and large data sets, available offshore, but also onland when offshore data were scarce or lacking. Three main projects have enabled to collect the offshore data: (1) the project “Seismic stratigraphy, Southern Bight, North Sea” (RCMG, City of London Polytechnic/NERC, University of Caen/CNRS); (2) the project “Seismisch onderzoek op het Belgisch Continentaal Plat. Eerste faze. Ontginningszone 2” (MEZ/Administratie van het Mijnwezen, RCMG); (3) the project “Studie oppervlaktelaag van het Belgisch Continentaal Plat. Seismisch prospectie sector B” MEZ/Belgian Geological Survey-BGD, RCMG). Data consist mainly of seismic profiles (16,000 km), cores (79) and cone penetration tests (CPTs, 177). All the data have been digitised and integrated in appropriate georeferenced softwares. Synthetic integrated maps and tables have been produced, aimed to provide the end-users with clear and directly usable information.This synthesis has been conducted in the framework of the project “Optimal Offshore Wind Energy Developments in Belgium”, financed by the Belgian federal government (Federal Office for Scientific, Technical and Cultural Affairs). This project is in keeping with the part I project network “Production patterns and sustainable consumption” of the PADD II program. Objectives of this project consisted in providing recommendations for the selection of sites that are convenient with respect to the stability of offshore wind structures and the minimisation of geo-environmental impacts.

Ankle braces in sports are used for prevention of ankle sprains. Besides restricting inversion and eversion, it is possible that an ankle brace also reduces the functional range of motion of the ankle joint. Consequently, their use could also impair athletic performance. It is unlikely that prophylactic ankle bracing will gain wide acceptance if bracing hinders athletic performance. The purpose of this paper is to review the literature on the effect of ankle bracing on vertical jump height, running speed, agility and broad jump performance. In 2 studies, 2 ankle braces negatively affected vertical jump height. Other studies did not find a significant effect on vertical jump performance when wearing an ankle brace. One study found a negative effect on running speed and broad jump performance when wearing a lace-on brace. In other studies, no effects on running speed and broad jump were found. In 1 study, agility was negatively affected when wearing an ankle brace, although agility was not significantly affected in other studies. The effect of prolonged use of an ankle brace is un-known, but could possibly influence ankle musculature and ligament function. Further research is necessary to study the effect of prolonged ankle bracing on performance.