3,044 research outputs found
On association in regression: the coefficient of determination revisited
Universal coefficients of determination are investigated which quantify the strength of the relation between a vector of dependent variables Y and a vector of independent covariates X. They are defined as measures of dependence between Y and X through theta(x), with theta(x) parameterizing the conditional distribution of Y given X=x. If theta(x) involves unknown coefficients gamma the definition is conditional on gamma, and in practice gamma, respectively the coefficient of determination has to be estimated. The estimates of quantities we propose generalize R^2 in classical linear regression and are also related to other definitions previously suggested. Our definitions apply to generalized regression models with arbitrary link functions as well as multivariate and nonparametric regression. The definition and use of the proposed coefficients of determination is illustrated for several regression problems with simulated and real data sets
“It’s like uprooting trees”: responsive treatment for a case of complex post-traumatic stress disorder following multiple rapes
This systematic case study documents 27 sessions of assessment and treatment with cognitive therapy of Bongi (23)who presented with major depression, posttraumatic stress disorder and borderline traits. Bongi had been raised in a punitive environment, had been raped three times, the first time at age 9, and had been in a series of abusive relationships. The treatment illustrates the importance of therapist responsiveness in addressing this kind of complex presentation, the importance of drawing on case formulation to guide the course of treatment and the range of different interventions that need to be incorporated into an integrative treatment of a complex case. Self-report measures of depression, anxiety and posttraumatic stress indicators provided evidence that the therapy contributed to positive changes and the qualitative therapy narrative gives details of the nature of some of those changes. Although treatment was not complete when Bongi moved away, Bongi herself judged that the therapy had been a valuable experience which had resulted in her feeling more alive, more confident, and better able to take care of herself
Trauma unit workload at King Edward VIII Hospital, Durban, KwaZulu-Natal
Each year, 70 000 South Africans are killed by trauma, and a further 3.5 million seek trauma care. We analysed 1 465 trauma patients at the regional-level King Edward VIII Hospital (KE8H) in eThekwini Municipality. Mean patient age was 29 years. Peaks in patient numbers were observed mid-month, at month-end, between 08h00 and 12h00 daily and on Saturday and Sunday nights. Most injuries occurred on roads, at informal settlements and at bars/shebeens. More than 44% of injuries had a violent cause. The pattern of presentation was more in line with a primary healthcaresetting than a referral centre. Reliable and accurate injury trend information is required for effective strategies to curb South Africa’s high injury mortality and morbidity rates. Epidemiological databases are needed, as well as safe, robust and ethical systems for collecting, collating, analysing and disseminating non-fatal injury related data
Die Reg van die Kind op Kontak met Beide Ouers: Opmerkings na Aanleiding van Onlangse Ontwikkelinge in die Nederlandse Reg
This contribution discusses the amendment to section 1: 377a lid 1 BW of 1 March 2009, in Dutch law. According to this provision a child has the right to have contact with both parents as well as with those who have sufficient close personal links with the child. The parent who is not responsible for the physical care of the child has the right and obligation to have contact with the child. The question whether the South African law, through the provisions of section 28 of the Constitution and the Children's Act, provides such a right and obligation, is investigated. Even though the conclusion is reached that the South African law indirectly provides such right and obligation, it is argued that the explicit recognition thereof in the Children's Act would provide a statutory legal duty on parents to have and maintain contact with their child. This would enhance legal certainty. Attention is also given to the enforcement of such right of the child.
Trauma unit workload at King Edward VIII Hospital, Durban, KwaZulu-Natal
Each year, 70 000 South Africans are killed by trauma and a further 3.5 million seek trauma care. We analysed 1 465 trauma patients at the regional-level King Edward VIII hospital (KE8H) in eThekwini Municipality. Mean patient age was 29 years. Peaks in patient numbers were observed mid-month, at month-end, between 08h00 and 12h00 daily and on Saturday and Sunday nights. Most injuries occurred on roads, at informal settlements and at bars/shebeens. More than 44% of injuries had a violent cause. The pattern of presentation was more in line with a primary healthcare setting than a referral centre. Reliable and accurate injury trend information is required for effective strategies to curb South Africa’s high injury mortality and morbidity rates. Epidemiological databases are needed, as well as safe, robust and ethical systems for collecting, collating, analysing and disseminating non-fatal injury-related data
Early functional outcome after subvastus or parapatellar approach in knee arthroplasty is comparable: a performance-based trial with anatomical findings
The role of dissociation-related beliefs about memory in trauma-focused treatment
OBJECTIVE: Dysfunctional cognitions play a central role in the development of post-traumatic stress disorder (PTSD). However the role of specific dissociation-related beliefs about memory has not been previously investigated. This study aimed to investigate the role of dissociation-related beliefs about memory in trauma-focused treatment. It was hypothesized that patients with the dissociative subtype of PTSD would show higher levels of dissociation-related beliefs, dissociation-related beliefs about memory would decrease after trauma-focused treatment, and higher pre-treatment dissociation-related beliefs would be associated with fewer changes in PTSD symptoms.METHOD: Post-traumatic symptoms, dissociative symptoms, and dissociation-related beliefs about memory were assessed in a sample of patients diagnosed with PTSD ( n = 111) or the dissociative subtype of PTSD ( n = 61). They underwent intensive trauma-focused treatment consisting of four or eight consecutive treatment days. On each treatment day, patients received 90 min of individual prolonged exposure (PE) in the morning and 90 min of individual eye movement desensitization and reprocessing (EMDR) therapy in the afternoon. The relationship between dissociation-related beliefs about memory and the effects of trauma-focused treatment was investigated. RESULTS: Dissociation-related beliefs about memory were significantly associated with PTSD and its dissociative symptoms. In addition, consistent with our hypothesis, patients with the dissociative subtype of PTSD scored significantly higher on dissociation-related beliefs about memory pre-treatment than those without the dissociative subtype. Additionally, the severity of these beliefs decreased significantly after trauma-related treatment. Contrary to our hypothesis, elevated dissociation-related beliefs did not negatively influence treatment outcome.CONCLUSION: The results of the current study suggest that dissociation-related beliefs do not influence the outcome of trauma-focused treatment, and that trauma-focused treatment does not need to be altered specifically for patients experiencing more dissociation-related beliefs about memory because these beliefs decrease in association with treatment.</p
Electromechanical reciprocity and arrhythmogenesis in long-QT syndrome and beyond.
An abundance of literature describes physiological and pathological determinants of cardiac performance, building on the principles of excitation-contraction coupling. However, the mutual influencing of excitation-contraction and mechano-electrical feedback in the beating heart, here designated 'electromechanical reciprocity', remains poorly recognized clinically, despite the awareness that external and cardiac-internal mechanical stimuli can trigger electrical responses and arrhythmia. This review focuses on electromechanical reciprocity in the long-QT syndrome (LQTS), historically considered a purely electrical disease, but now appreciated as paradigmatic for the understanding of mechano-electrical contributions to arrhythmogenesis in this and other cardiac conditions. Electromechanical dispersion in LQTS is characterized by heterogeneously prolonged ventricular repolarization, besides altered contraction duration and relaxation. Mechanical alterations may deviate from what would be expected from global and regional repolarization abnormalities. Pathological repolarization prolongation outlasts mechanical systole in patients with LQTS, yielding a negative electromechanical window (EMW), which is most pronounced in symptomatic patients. The electromechanical window is a superior and independent arrhythmia-risk predictor compared with the heart rate-corrected QT. A negative EMW implies that the ventricle is deformed-by volume loading during the rapid filling phase-when repolarization is still ongoing. This creates a 'sensitized' electromechanical substrate, in which inadvertent electrical or mechanical stimuli such as local after-depolarizations, after-contractions, or dyssynchrony can trigger abnormal impulses. Increased sympathetic-nerve activity and pause-dependent potentiation further exaggerate electromechanical heterogeneities, promoting arrhythmogenesis. Unraveling electromechanical reciprocity advances the understanding of arrhythmia formation in various conditions. Real-time image integration of cardiac electrophysiology and mechanics offers new opportunities to address challenges in arrhythmia management
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