High-pressure behaviour of an X-ray preionized discharge pumped XeCl laser

The output characteristics are described of an X-ray preionized discharge pumped XeCl laser, fed by a low-impedance pulse forming line (PFL), at pressures up to 12 bar. The influence of a multichannel rail gap placed between the PFL and the laser head on the output energy was studied. We found an increase of output energy with increasing pressure up to 8 bar. At higher pressures a saturation behaviour was found. The maximum output energy per unit volume was 6.5 J/l

An improved discharge technique for excimer lasers

The further development of discharge excimer lasers depends upon a better degree of control over the discharge stability. A problem is the large difference between the breakdown and steady-state voltage which requires a time dependent impedance of the power circuit. Further the large attachment rates of halogens like HCl, causing electric field disturbances require a short rise time of the applied current pulse. A large effort has been expended towards this goal by researchers since the early development of discharge excimer lasers

Connecting the Kuramoto Model and the Chimera State

Since its discovery in 2002, the chimera state has frequently been described as a counter-intuitive, puzzling phenomenon. The Kuramoto model, in contrast, has become a celebrated paradigm useful for understanding a range of phenomena related to phase transitions, synchronization and network effects. Here we show that the chimera state can be understood as emerging naturally through a symmetry breaking bifurcation from the Kuramoto model's partially synchronized state. Our analysis sheds light on recent observations of chimera states in laser arrays, chemical oscillators, and mechanical pendula.Comment: 5 pages, 6 figure

Calendar 2009

BACKGROUND: Given the increase in skin cancer (SC) it seems inevitable that general practitioners (GPs) will play a larger role in SC care in the near future. OBJECTIVES: To obtain insights into the opinion of GPs with respect to their role in SC care, and their SC knowledge and skills. METHODS: A self-administered questionnaire was sent to GPs in the region of Nijmegen, the Netherlands. RESULTS: In total 268 GPs (49%) responded. An overwhelming majority were willing to extend their role in SC care. Furthermore, we noted the following results: (i) > 50% of GPs requested additional SC knowledge; (ii) GPs often treat actinic keratosis (AK) themselves, primarily with cryotherapy; (iii) > 50% would treat (low-risk) basal cell carcinoma (BCC) after additional training; (iv) only a few GPs are familiar with BCC guidelines; (v) the majority of patients with high-risk SC are referred to dermatologists; (vi) only a few GPs perform total body inspection and palpation of lymph nodes; and (vii) a large number of GPs inform their patients on risk factors in SC development. CONCLUSIONS: Most GPs are willing to extend their role in SC care; however, more training is requested and the usage of guidelines should be encouraged. Those willing to extend their role should focus on improving their clinical diagnosis of skin tumours, treatment of low-risk skin (pre)malignancies, including field-directed treatment of AK and noninvasive treatment of BCC, and on prevention

Leren van het energieke platteland : lokale en regionale coalities voor duurzame plattelandsontwikkeling

In deze studie onderzoeken we de kracht van de samenwerking tussen de verschillende gebruikers van het platteland. Burgers, boeren, natuurbeheerders en bedrijven die samen initiatieven ontplooien om hun leefomgeving te verbeteren. De studie laat aan de hand van een breed scala aan praktijkvoorbeelden zien hoe ze dat doen, wat ze proberen te bereiken en waar ze tegenaan lopen. Zo zijn er moderne boeren die samen met andere ketenpartijen hun bedrijfsvoering nog verder willen verduurzamen dan de wet al voorschrijft, en burgers die met boeren lokale coöperaties opzetten voor de opwekking van hernieuwbare energie

Gender differences in respiratory symptoms in 19-year-old adults born preterm

Objective: To study the prevalence of respiratory and atopic symptoms in (young) adults born prematurely, differences between those who did and did not develop Bronchopulmonary Disease (BPD) at neonatal age and differences in respiratory health between males and females. Methods: Design: Prospective cohort study. Setting: Nation wide follow-up study, the Netherlands. Participants: 690 adults (19 year old) born with a gestational age below 32 completed weeks and/or with a birth weight less than 1500g. Controls were Dutch participants of the European Community Respiratory Health Survey (ECRHS). Main outcome measures: Presence of wheeze, shortness of breath, asthma, hay fever and eczema using the ECRHS-questionnaire