The tropospheric response pattern to solar activity forcing

It is tempting to speculate on the possibility that solar flares sometimes are the initial cause of and atmospheric disturbance, which cumulative effect may give rise to a correlation at the 11 year timescale. Reasons to reconsider the possible relevance of solar flare response studies are stated. The discovery of the apparently decisive role of the Quasi-Biennial Oscillations (QBO) in establishing the atmospheric response pattern to solar forcing may throw new light on some of the earlier published relations. Reanalysis of old data in some cases may be advisable. Data on solar flares and their effects on the earth's atmosphere might be a promising candidate for reexamination

Convex relaxation of mixture regression with efficient algorithms

We develop a convex relaxation of maximum a posteriori estimation of a mixture of regression models. Although our relaxation involves a semidefinite matrix variable, we reformulate the problem to eliminate the need for general semidefinite programming. In particular, we provide two reformulations that admit fast algorithms. The first is a max-min spectral reformulation exploiting quasi-Newton descent. The second is a min-min reformulation consisting of fast alternating steps of closed-form updates. We evaluate the methods against Expectation-Maximization in a real problem of motion segmentation from video data

Continuous blood pressure monitoring:The pulse of hemodynamics

Critical illnesses and surgical procedures can impede the continuous blood flow to vital organs, potentially resulting in inadequate oxygen supply to meet their metabolic demands. Monitoring tools to assess organ perfusion are not readily available at the patient's bedside. Therefore, blood pressure measurements currently serve as a surrogate to estimate a patient's circulatory state. The first part of this thesis offers an overview of how critically low arterial blood pressure, also known as hypotension, is defined, monitored, and treated in intensive care units (ICUs) across various countries worldwide. Additionally, it provides insight into the effects of hypotension exposure during an ICU stay on patient outcomes. To prevent hypotension-related organ injury, blood pressure is often continuously monitored in critically ill patients, allowing for immediate alarms and prompt treatment if hypotension occurs. However, hypotension, and therefore organ injury, already occurred at that point. Moreover, selecting the appropriate treatment can be challenging as the cause of the blood pressure drop may be unclear. The final part of this thesis focuses on the prediction and prevention of hypotensive events during cardiac surgery and postoperative intensive care unit stay using continuous blood pressure monitoring and machine learning

Definition and incidence of hypotension in intensive care unit patients, an international survey of the European Society of Intensive Care Medicine

Introduction: Although hypotension in ICU patients is associated with adverse outcome, currently used definitions are unknown and no universally accepted definition exists. Methods: We conducted an international, peer-reviewed survey among ICU physicians and nurses to provide insight in currently used definitions, estimations of incidence, and duration of hypotension. Results: Out of 1394 respondents (1055 physicians (76%) and 339 nurses (24%)), 1207 (82%) completed the questionnaire. In all patient categories, hypotension definitions were predominantly based on an absolute MAP of 65 mmHg, except for the neuro(trauma) category (75 mmHg, p &lt; 0.001), without differences between answers from physicians and nurses. Hypotension incidence was estimated at 55%, and time per day spent in hypotension at 15%, both with nurses reporting higher percentages than physicians (estimated mean difference 5%, p = 0.01; and 4%, p &lt; 0.001). Conclusions: An absolute MAP threshold of 65 mmHg is most frequently used to define hypotension in ICU patients. In neuro(trauma) patients a higher threshold was reported. The majority of ICU patients are estimated to endure hypotension during their ICU admission for a considerable amount of time, with nurses reporting a higher estimated incidence and time spent in hypotension than physicians.</p

The BeppoSAX WFC X-ray source catalogue

We present the catalogue of X-ray sources detected by the two Wide Field Cameras (WFCs) in complete observations on board BeppoSAX during its 6 years of operational lifetime, between April 1996 and April 2002. The BeppoSAX WFCs were coded mask instruments sensitive in the 2-28 keV energy band with a 40x40 square degree fields of view, pointing in opposite directions and perpendicularly to the BeppoSAX Narrow Field Instruments (NFI). The WFCs were usually operated simultaneously to NFI observations, each lasting up to several days. WFCs observed thus the entire sky several times with a typical sensitivity of 2 to 10 mCrab. A systematic analysis of all WFC observations in the BeppoSAX archive has been carried out using the latest post-mission release of the WFC analysis software and calibrations. The catalogue includes 253 distinct sources, obtained from a total sample of 8253 WFC detections. We describe the basic statistical properties of the sample and present a six-year history of two celestial calibration X-ray sources.Comment: 15 pages, 11 figures, Catalogue, Accepted for publication on A&

THE BLOOD-SUCKING ARTHROPODS OF THE DUTCH EAST INDIAN ARCHIPELAGO

abstract not availabl

Tabanidae

abstract not availabl

The Neecham Confusion Scale and the Delirium Observation Screening Scale: Capacity to discriminate and ease of use in clinical practice

BACKGROUND: Delirium is a frequent form of psychopathology in elderly hospitalized patients; it is a symptom of acute somatic illness. The consequences of delirium include high morbidity and mortality, lengthened hospital stay, and nursing home placement. Early recognition of delirium symptoms enables the underlying cause to be diagnosed and treated and can prevent negative outcomes. The aim of this study was to determine which of the two delirium observation screening scales, the NEECHAM Confusion Scale or the Delirium Observation Screening (DOS) scale, has the best discriminative capacity for diagnosing delirium and which is more practical for daily use by nurses. METHODS: The project was conducted on four wards of a university hospital; 87 patients were included. During 3 shifts, these patients were observed for symptoms of delirium, which were rated on both scales. A DSM-IV diagnosis of delirium was made or rejected by a geriatrician. Nurses were asked to rate the practical value of both scales using a structured questionnaire. RESULTS: The sensitivity (0.89 – 1.00) and specificity (0.86 – 0.88) of the DOS and the NEECHAM were high for both scales. Nurses rated the practical use of the DOS scale as significantly easier than the NEECHAM. CONCLUSION: Successful implementation of standardized observation depends largely on the consent of professionals and their acceptance of a scale. In our hospital, we therefore chose to involve nurses in the choice between two instruments. During the study they were able to experience both scales and give their opinion on ease of use. In the final decision on the instrument we found that both scales were very acceptable in terms of sensitivity and specificity, so the opinion of the nurses was decisive. They were positive about both instruments; however, they rated the DOS scale as significantly easier to use and relevant to their practice. Our findings were obtained from a single site study with a small sample, so a large comparative trial to study the value of both scales further is recommended. On the basis of our experience during this study and findings from the literature with regard to the implementation of delirium guidelines, we will monitor the further implementation of the DOS Scale in our hospital with intensive consultation