bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II: Imperfect Model Experiments
Authors: Meng Zhiyong , Zhang Fuqing 
Published: April 2007

Abstract
In Part I of this two-part work, the feasibility of using an ensemble Kalman filter (EnKF) for mesoscale and regional-scale data assimilation through various observing system simulation experiments was demonstrated assuming a perfect forecast model for a winter snowstorm event that occurred on 24–26 January 2000. The current study seeks to explore the performance of the EnKF for the same event in the presence of significant model errors due to physical parameterizations by assimilating synthetic sounding and surface observations with typical temporal and spatial resolutions. The EnKF performance with imperfect models is also examined for a warm-season mesoscale convective vortex (MCV) event that occurred on 10–13 June 2003. The significance of model error in both warm- and cold-season events is demonstrated when the use of different cumulus parameterization schemes within different ensembles results in significantly different forecasts in terms of both ensemble mean and spread. Nevertheless, the EnKF performed reasonably well in most experiments with the imperfect model assumption (though its performance can sometimes be significantly degraded). As in Part I, where the perfect model assumption was utilized, most analysis error reduction comes from larger scales. Results show that using a combination of different physical parameterization schemes in the ensemble forecast can significantly improve filter performance. A multischeme ensemble has the potential to provide better background error covariance estimation and a smaller ensemble bias. There are noticeable differences in the performance of the EnKF for different flow regimes. In the imperfect scenarios considered, the improvement over the reference ensembles (pure ensemble forecasts without data assimilation) after 24 h of assimilation for the winter snowstorm event ranges from 36% to 67%. This is higher than the 26%–45% improvement noted after 36 h of assimilation for the warm-season MCV event. Scale- and flow-dependent error growth dynamics and predictability are possible causes for the differences in improvement. Compared to the power spectrum analyses for the snowstorm, it is found that forecast errors and ensemble spreads in the warm-season MCV event have relatively smaller power at larger scales and an overall smaller growth rate.
Environmental Control of Cloud-to-Ground Lightning Polarity in Severe Storms
Authors: Carey Lawrence D. , Buffalo Kurt M. 
Published: April 2007

Abstract
In this study, it is hypothesized that the mesoscale environment can indirectly control the cloud-to-ground (CG) lightning polarity of severe storms by directly affecting their structural, dynamical, and microphysical properties, which in turn directly control cloud electrification and ground flash polarity. A more specific hypothesis, which has been supported by past observational and laboratory charging studies, suggests that broad, strong updrafts and associated large liquid water contents in severe storms lead to the generation of an inverted charge structure and enhanced +CG lightning production. The corollary is that environmental conditions favoring these kinematic and microphysical characteristics should support severe storms generating an anomalously high (&gt;25%) percentage of +CG lightning (i.e., positive storms) while environmental conditions relatively less favorable should sustain storms characterized by a typical (≤25%) percentage of +CG lightning (i.e., negative storms). Forty-eight inflow proximity soundings were analyzed to characterize the environment of nine distinct mesoscale regions of severe storms (4 positive and 5 negative) on 6 days during May–June 2002 over the central United States. This analysis clearly demonstrated significant and systematic differences in the mesoscale environments of positive and negative storms, which were consistent with the stated hypothesis. When compared to negative storms, positive storms occurred in environments associated with a drier low to midtroposphere, higher cloud-base height, smaller warm cloud depth, stronger conditional instability, larger 0–3 km AGL wind shear, stronger 0–2 km AGL storm relative wind speed, and larger buoyancy in the mixed-phase zone, at a statistically significant level. Differences in the warm cloud depth of positive and negative storms were by far the most dramatic, suggesting an important role for this parameter in controlling CG lightning polarity. In this study, strong correlations between the mesoscale environment and CG lightning polarity were demonstrated. However, causality could not be verified due to a lack of in situ observations to confirm the hypothesized microphysical, dynamical, and electrical responses to variations in environmental conditions that ultimately determined the dominant CG polarity. Future observational field programs and cloud modeling studies should focus on these critical intermediary processes.
Theory and Applications of the Minimum Spanning Tree Rank Histogram
Authors: Gombos Daniel , Hansen James A. , Du Jun , McQueen Jeff 
Published: April 2007

Abstract
A minimum spanning tree (MST) rank histogram (RH) is a multidimensional ensemble reliability verification tool. The construction of debiased, decorrelated, and covariance-homogenized MST RHs is described. Experiments using Euclidean L2, variance, and Mahalanobis norms imply that, unless the number of ensemble members is less than or equal to the number of dimensions being verified, the Mahalanobis norm transforms the problem into a space where ensemble imperfections are most readily identified. Short-Range Ensemble Forecast Mahalanobis-normed MST RHs for a cluster of northeastern U.S. cities show that forecasts of the temperature–humidity index are the most reliable of those considered, followed by mean sea level pressure, 2-m temperature, and 10-m wind speed forecasts. MST RHs of a Southwest city cluster illustrate that 2-m temperature forecasts are the most reliable weather component in this region, followed by mean sea level pressure, 10-m wind speed, and the temperature–humidity index. Forecast reliabilities of the Southwest city cluster are generally less reliable than those of the Northeast cluster.
Scoring Probabilistic Forecasts: The Importance of Being Proper
Authors: Bröcker Jochen , Smith Leonard A. 
Published: April 2007

AbstractQuestions remain regarding how the skill of operational probabilistic forecasts is most usefully evaluated or compared, even though probability forecasts have been a long-standing aim in meteorological forecasting. This paper explains the importance of employing proper scores when selecting between the various measures of forecast skill. It is demonstrated that only proper scores provide internally consistent evaluations of probability forecasts, justifying the focus on proper scores independent of any attempt to influence the behavior of a forecaster. Another property of scores (i.e., locality) is discussed. Several scores are examined in this light. There is, effectively, only one proper, local score for probability forecasts of a continuous variable. It is also noted that operational needs of weather forecasts suggest that the current concept of a score may be too narrow; a possible generalization is motivated and discussed in the context of propriety and locality.
Application of Artificial Neural Network Forecasts to Predict Fog at Canberra International Airport
Authors: Fabbian Dustin , de Dear Richard , Lellyett Stephen 
Published: April 2007

AbstractThe occurrence of fog can significantly impact air transport operations, and plays an important role in aviation safety. The economic value of aviation forecasts for Sydney Airport alone in 1993 was estimated at $6.8 million (Australian dollars) for Quantas Airways. The prediction of fog remains difficult despite improvements in numerical weather prediction guidance and models of the fog phenomenon. This paper assesses the ability of artificial neural networks (ANNs) to provide accurate forecasts of such events at Canberra International Airport (YSCB). Unlike conventional statistical techniques, ANNs are well suited to problems involving complex nonlinear interactions and therefore have potential in application to fog prediction. A 44-yr database of standard meteorological observations obtained from the Australian Bureau of Meteorology was used to develop, train, test, and validate ANNs designed to predict fog occurrence. Fog forecasting aids were developed for 3-, 6-, 12-, and 18-h lead times from 0600 local standard time. The forecasting skill of various ANN architectures was assessed through analysis of relative operating characteristic curves. Results indicate that ANNs are able to offer good discrimination ability at all four lead times. The results were robust to error perturbation for various input parameters. It is recommended that such models be included when preparing forecasts for YSCB, and that the technique should be extended in its application to cover other similarly fog-prone aviation locations.
A Western Australian Survey On Public Attitudes Toward and Knowledge of Electroconvulsive Therapy
Authors: Teh Serene P.C. , Helmes Edward , Drake Deirdre G. 
Published: April 2007

Aims: Healthcare professionals have debated the use and effects of electroconvulsive therapy (ECT) for more than 65 years. Yet, knowledge about, and attitudes towards, ECT have not been thoroughly researched within the Australian community. This study focused on a Western Australian perspective on these issues. Method: The objectives were achieved with specifically developed questionnaires. Six hundred surveys were distributed across the metropolitan area of Perth, Australia. Results: A total of 379 completed questionnaires indicated that more than 60% of respondents had some knowledge about the main aspects of ECT. Participants were generally opposed to the use of ECT on individuals with psychosocial issues, on children and on involuntary patients. Public perceptions of ECT were also found to be mainly negative. Conclusion: The findings suggest that clinicians should ensure that individuals recommended for ECT are knowledgeable about basic ECT processes and implications in order to ensure their full informed consent.
Factors Influencing Attitudes Towards Seeking Professional Help Among East and Southeast Asian Immigrant and Refugee Women
Authors: Fung Kenneth , Wong Yuk-Lin Renita 
Published: April 2007

Background and aims: It has been recognized that Asian immigrants in North America have lower rates of mental health service utilization. From the perspective of cross-cultural psychiatry, one of the most important cultural factors may be differences in the explanatory model of illness. This article examines the relationship of causal beliefs, perceived service accessibility and attitudes towards seeking mental health care. Method: The sample consisted of 1000 immigrant and refugee women from five ethnic minority communities in Toronto, including three Chinese Canadian communities (Hong Kong, mainland China and Taiwan), Korean Canadians and Vietnamese Canadians. Data were acquired by a self-administered structured questionnaire. Quantitative data were analysed using MANOVA, ANOVA and stepwise multiple regression. Results: The five ethnic minority groups of women differed in their explanatory models about mental illness and distress. In the full model where other variables were controlled for, the most significant factor predicting attitudes towards seeking professional help was perceived access for all groups except the Hong Kong Chinese. In the last group, those subscribing more to a Western stress model of illness had a more positive attitude towards seeking professional help, while those subscribing more to supernatural beliefs had a more negative attitude. Age and education were not significant predictors. Conclusion: Perceived access is one of the main factors that influence attitudes toward seeking professional help. Explanatory models may predict help-seeking behaviours if perceived access to such services is available.
Psychological Distress in Caretakers or Relatives of Patients With Borderline Personality Disorder
Authors: Scheirs J.G.M. , Bok S. 
Published: April 2007

Background and aims: Caregivers or relatives of mental patients often show increased levels of psychological distress. This study investigated whether this is also the case for caregivers of patients with borderline personality disorder. Methods: The Symptom Check List (SCL-90) was administered to 64 Dutch volunteers, who were either biologically related (parents or siblings) or biologically unrelated caregivers (partners or friends) of patients with borderline personality disorder. Results: The group of caregivers as a whole scored higher on all symptom dimensions of the SCL-90 than the general population. When controlling for caregiver sex and age, as well as for patient sex, there were no significant differences between the biologically related and unrelated caregiver groups on any dimension. Conclusions: The results are in line with findings concerning distress in caregivers of patients suffering from personality disorders in general, posttraumatic stress disorder or schizophrenia. The mechanism behind the increased levels of distress in our sample is not clear, however. Either exposure to the problematic behaviour of the patient, selective mating or a combination of both might have been responsible for the effect.
Borderline Personality Disorder: Neo-Personality Inventory Ratings of Patients and Their Family Members
Authors: Hoffman Perry D. , Buteau Ellie , Fruzzetti Alan E. 
Published: April 2007

Borderline personality disorder (BPD) is hallmarked by interpersonal problems. Conflicts with family members are no exception. Methods: The NEO-Personality Inventory was administered to 25 pairs of patients and their family members. Both completed the questionnaire twice, responding about their own personality traits and responding about personality traits of the other. Results: Patients and family members agreed on all five of the patient's personality traits. However, patients perceived the family members as being more neurotic, less extraverted and less open than the family members perceived themselves. Conclusions: Discrepant perceptions of personality traits `may' create different relationship expectations and thus contribute to and intensify interpersonal difficulties.
Noise levels and noise sources in acute care hospital wards
Authors: MacKenzie D.J. , Galbrun L. 
Published: April 2007

Noise in hospital wards has the potential to slow down the recovery of patients. A comprehensive and systematic analysis of noise levels and noise sources has been carried out in two intensive care units and one high dependency unit in two Edinburgh hospitals (UK). Noise levels LAeq,1min and LAFmax were measured at 1 minute intervals for 24 hour periods, and noise sources responsible for LAFmax were identified. High noise levels were found in the three wards, the lowest LAeq,1min being measured in the modern ward tested, where an acoustic ceiling was present. A substantial number of noise sources have been observed and analysed statistically, many of which had never been identified by previous research. It was found that 34% of these are totally avoidable and 28% are partially avoidable. Noise control solutions are presented, with practical solutions affecting 48% of the noise sources, and staff education affecting 14% of the sources. Practical application: The analysis and classification of noise sources obtained has lead to the identification and presentation of practical noise control solutions, some of which can be implemented at the design stage. This is of direct relevance to building services engineers who play a role in the design of hospital wards, and can therefore use this information. It can also be noted that average and maximum noise levels measured in this study could form the basis for the development of noise guidelines in intensive care units and high dependency units, as current limits do not appear to be appropriate for such spaces.
Risk of Tearing the Intact Anterior Cruciate Ligament in the Contralateral Knee and Rupturing the Anterior Cruciate Ligament Graft during the First 2 Years after Anterior Cruciate Ligament Reconstruction
Authors: Wright Rick W. , Dunn Warren R. , Amendola Annunziato , Andrish Jack T. , Bergfeld John , Kaeding Christopher C. , Marx Robert G. , McCarty Eric C. , Parker Richard D. , Wolcott Michelle , Wolf Brian R. , Spindler Kurt P. 
Published: April 2007

Background The risk of tear of the intact anterior cruciate ligament in the contralateral knee after anterior cruciate ligament reconstruction of the opposite knee and the incidence of rupturing the anterior cruciate ligament graft during the first 2 years after surgery have not been extensively studied in a prospective manner. Clinicians have hypothesized that the opposite normal knee is at equal or increased risk compared with the risk of anterior cruciate ligament graft rupture in the operated knee. Hypothesis The risk of anterior cruciate ligament graft rupture and contralateral normal knee anterior cruciate ligament rupture at 2-year follow-up is equal. Study Design Cohort study; Level of evidence, 2. Methods The Multicenter Orthopaedic Outcome Network (MOON) database of a prospective longitudinal cohort of anterior cruciate ligament reconstructions was used to determine the number of anterior cruciate ligament graft ruptures and tears of the intact anterior cruciate ligament in the contralateral knee at 2-year follow-up. Two-year follow-up consisted of a phone interview and review of operative reports. Results Two-year data were obtained for 235 of 273 patients (86%). There were 14 ligament disruptions. Of these, 7 were tears of the intact anterior cruciate ligament in the contralateral knee (3.0%) and 7 were anterior cruciate ligament graft failures (3.0%). Conclusion The contralateral normal knee anterior cruciate ligament is at a similar risk of anterior cruciate ligament tear (3.0%) as the anterior cruciate ligament graft after primary anterior cruciate ligament reconstruction (3.0%).
The Effects of Common Anti-Inflammatory Drugs on the Healing Rat Patellar Tendon
Authors: Ferry Scott T. , Dahners Laurence E. , Afshari Hessam M. , Weinhold Paul S. 
Published: April 2007

Background Tendon injuries that occur at the osteotendinous junction are commonly seen in clinical practice and range from acute strain to rupture. Nonsteroidal anti-inflammatory drugs are often prescribed in the treatment of these conditions, but the effect that these agents may have on the healing response at the bone-tendon junction is unclear. Hypothesis In response to an acute injury at the osteotendinous junction, the healing patellar tendon will have inferior biomechanical properties with administration of anti-inflammatory drugs as compared with acetaminophen and control. Study Design Controlled laboratory study. Methods A total of 215 Sprague-Dawley rats underwent transection of the patellar tendon at the inferior pole of the patella, which was subsequently stabilized with a cerclage suture. The animals were then randomized into 7 groups and administered 1 of the following analgesics for 14 days ibuprofen, acetaminophen, naproxen, piroxicam, celecoxib, valdecoxib, or control. At 14 days, all animals were sacrificed, and the extensor mechanism was isolated and loaded to failure. Biochemical analysis of the repair site tissue was performed. Animal activity throughout the study was monitored using a photoelectric sensor system. Results The control group demonstrated greater maximum load compared with the celecoxib, valdecoxib, and piroxicam groups (P < .05). The acetaminophen and ibuprofen groups were also significantly stronger than the celecoxib group (P < .05) but not statistically different than the control group. A total of 23 specimens had failure of the cerclage suture with the following distribution control (0/23), ibuprofen (0/23), acetaminophen (0/24), naproxen (3/24), piroxicam (4/24), celecoxib (6/22), and valdecoxib (10/24). The difference in distribution of the failures was significant (P < .001). Conclusions Anti-inflammatory drugs, with the exception of ibuprofen, had a detrimental effect on healing strength at the bone-tendon junction as demonstrated by decreased failure loads and increased failures of the cerclage suture. Acetaminophen had no effect on healing strength. The biomechanical properties paralleled closely with the total collagen content at the injury site, suggesting that these agents may alter healing strength by decreasing collagen content. Clinical Relevance Selective and nonselective cyclooxygenase (COX) inhibitors should be used judiciously in the acute period after injury or surgical repair at the bone-tendon junction.
Can a Double-Row Anchorage Technique Improve Tendon Healing in Arthroscopic Rotator Cuff Repair?
Authors: Charousset Christophe , Grimberg Jean , Duranthon Louis Denis , Bellaiche Laurance , Petrover David 
Published: April 2007

Background Increasing the rate of watertight tendon healing has been suggested as an important criterion for optimizing clinical results in rotator cuff arthroscopic repair. Hypothesis A double-row anchorage technique for rotator cuff repair will produce better clinical results and a better rate of tendon healing than a single-row technique. Study Design Cohort study; Level of evidence, 2. Methods We compared 31 patients undergoing surgery with a double-row anchorage technique using Panalok anchors and Cuff Tack anchors and 35 patients with rotator cuff tear undergoing surgery with a single-row anchorage arthroscopic technique using Panalok anchors. We compared pre- and postoperative Constant score and tendon healing, as evaluated by computed tomographic arthrography 6 months after surgery, in these 2 groups. Results The Constant score increased significantly in both groups, with no difference between the 2 groups (P = .4). Rotator cuff healing was judged anatomic in 19 patients with double-row anchorage and in 14 patients with single-row anchorage; this difference between the groups was significant (P = .03). Conclusion In this first study comparing double- and single-row anchorage techniques, we found no significant difference in clinical results, but tendon healing rates were better with the double-row anchorage. Improvements in the double-row technique might lead to better clinical and tendon healing results.