BACKGROUND/PURPOSE The advice that an adequate vitamin D status can be achieved by short, casual exposure to summer sunlight is ubiquitous. This review will examine the value of this advice. METHODS The results of experimental studies on changes in serum 25-hydroxyvitamin D [25(OH)D] concentrations following ultraviolet exposure are interpreted in the context of human exposure to sunlight. ...

1 Health Technology Assessment Unit, Institute for Research in Extramural Medicine, VU University Medical Center, Amsterdam, The Netherlands 2 International Health Foundation, Utrecht, The Netherlands 3 Department of General Practice, Institute for Research in Extramural Medicine, VU University Medical Center, Amsterdam, The Netherlands 4 Institute for Research in Extramural Medicine, VU Univer...

This interlaboratory study on determination of 25-hydroxyvitamin D (25-OH-D) in serum involved 15 laboratories in eight European countries. All could distinguish between normal (50 +/- 31 nmol/L, mean +/- SD) and grossly increased concentrations, but for eight laboratories the results for serum samples with low and normal 25-OH-D content overlapped. In general, values were well reproducible, bu...

We analyze the internal spatial wage and employment structures of the Czech Republic, Hungary, Poland, Slovenia and Slovakia, using regional data for 1996-2000. A new economic geography model predicts wage gradients and specialization patterns that are smoothly related to regions’ relative market access. As an alternative, we formulate a “Comecon hypothesis”, according to which wages and sector...

In this work, a steady-state heat transfer equation in a side-pumped Nd:YAG laser rod was solved numerically using finite element method (FEA). The resulting temperature and stress distributions were calculated under the condition of totally and partially direct side pumping structures with LASCAD software. From the result of simulation, we compare between the different pumping lengths, and mai...

تعتبر قضية الأسرى الفلسطينيين داخل سجون الاحتلال الإس ا رئيلي إنسانية بامتياز،كونها تمس كل عائلة فلسطينية نتيجة لغياب الزوج أو الزوجة الابن، فلا يكاد يخلو بيت فلسطينيإلا ويوجد به أسير أكثر، ولم تسلم من هذه الاعتقالات حتى النساء والأطفال وكبار السن.وتمثلت مشكلة الد رسة في التعرف على دور العلاقات العامة و زرة شؤون والمحررينفي توعية الجمهور الفلسطيني بقضية الأسرى، وطبيعة هذا الدور والوسائل المتبعة...

helicobacter pylori is a gram-negative, spiral-shaped, microaerophilic organism that colonizes the stomach of humans and causes chronic-active gastritis, peptic ulcer disease, and gastric cancers, including adenocarcinoma of the stomach and malt (mucosal-associated lymphoid tumor) lymphomas. h. pylori colonizes the stomach of over 50 % the world’s human population, primarily those who reside in...