Predicting the behaviour of structures under impact loads using geometrically distorted scaled models

When a scaled structure (model or replica) is used to predict the response of a full-size compound (prototype), the model geometric dimensions should relate to the corresponding prototype dimensions by a single scaling factor. However, owing to manufacturing technical restrictions, this condition cannot be accomplished for some of the dimensions in real structures. Accordingly, the distorted geometry will not comply with the overall geometric scaling factor, infringing the Pi theorem requirements for complete dynamic similarity. In the present study, a method which takes geometrical distortions into account is introduced, leading to a model similar to the prototype. As a means to infer the performance of this method, three analytical problems of structures subjected to dynamic loads are analysed. It is shown that the replica developed applying this technique is able to accurately predict the full-size structure behaviour even when the studied models have some of their dimensions severely distorted. (C) 2012 Elsevier Ltd. All rights reserved.

'Impulsive compulsivity' in obsessive-compulsive disorder: A phenotypic marker of patients with poor clinical outcome

Although traditionally obsessive-compulsive disorder (OCD) and impulse control disorders (ICD) have represented opposing ends of a continuum, recent research has demonstrated a frequent co-occurrence of impulsive and compulsive behaviours, which may contribute to a worse clinical picture of some psychiatric disorders. We hypothesize that individuals with 'impulsive' OCD as characterized by poor insight, low resistance, and reduced control towards their compulsions will have a deteriorative course, greater severity of hoarding and/or symmetry/ordering symptoms, and comorbid ICD and/or substance use disorders (SUD). The sample consisted of 869 individuals with a minimum score of 16 on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Of these, 65 had poor insight, low resistance, and reduced control towards compulsions ('poor IRC') and 444 had preserved insight, greater resistance and better control over compulsions ('good IRC'). These two groups were compared on a number of clinical and demographic variables. Individuals with poor IRC were significantly more likely to have a deteriorative course (p < 0.001), longer duration of obsessions (p = 0.017), greater severity of symmetry/ordering (p < 0.001), contamination/cleaning (p < 0.001) and hoarding (p = 0.002) symptoms, and comorbid intermittent explosive disorder (p = 0.026), trichotillomania (p = 0.014) and compulsive buying (p = 0.040). Regression analysis revealed that duration of obsessions (p = 0.037) and hoarding severity (p = 0.005) were significant predictors of poor IRC. In the absence of specific measures for impulsivity in OCD, the study highlights the utility of simple measures such as insight, resistance and control over compulsions as a phenotypic marker of a subgroup of OCD with impulsive features demonstrating poor clinical outcome. (C) 2012 Elsevier Ltd. All rights reserved.

Neither bipolar nor obsessive-compulsive disorder: compulsive buyers are impulsive acquirers

Introduction: Compulsive buying (CB) is currently classified as an impulse control disorder (ICD) not otherwise classified. Compulsive buying prevalence is estimated at around 5% of the general population. There is controversy about whether CB should be classified as an ICD, a subsyndromal bipolar disorder (BD), or an obsessive-compulsive disorder (OCD) akin to a hoarding syndrome. To further investigate the appropriate classification of CB, we compared patients with CB, BD, and OCD for impulsivity, affective instability, hoarding, and other OCD symptoms. Method: Eighty outpatients (24 CB, 21 BD, and 35 OCD) who were neither manic nor hypomanic were asked to fill out self-report questionnaires. Results: Compulsive buying patients scored significantly higher on all impulsivity measures and on acquisition but not on the hoarding subdimensions of clutter and "difficulty discarding." Patients with BD scored higher on the mania dimension from the Structured Clinical Interview for Mood Spectrum scale. Patients with OCD scored higher on obsessive-compulsive symptoms and, particularly, higher on the contamination/washing and checking dimensions from the Padua Inventory; however, they did not score higher on any hoarding dimension. A discriminant model built with these variables correctly classified patients with CB (79%), BD (71%), and OCD (77%). Conclusion: Patients with CB came out as impulsive acquirers, resembling ICD- rather than BD- or OCD-related disorders. Manic symptoms were distinctive of patients with BD. Hoarding symptoms other than acquisition were not particularly associated with any diagnostic group. (C) 2012 Elsevier Inc. All rights reserved.

HIV-1 Proviral DNA Loads (as Determined by Quantitative PCR) in Patients Subjected to Structured Treatment Interruption after Antiretroviral Therapy Failure

The impact of Structured Treatment Interruption (STI) in peripheral blood mononuclear cell (PBMC) proviral reservoirs in 41 highly active antiretroviral therapy (HAART)-treated viremic individuals at baseline and 12 weeks after STI was determined using quantitative PCR (qPCR). Viral load increased 0.7 log(10) and CD4 decreased 97.5 cells/mm(3) after 12 weeks. A total of 28 of the 41 individuals showed an increased proviral load, 19 with a statistically significant increase above 10%. An increase in active viral replication is an important factor in the replenishment of the proviral reservoir even for short time periods.

Effectiveness of a long-term use of a minimalist footwear versus habitual shoe on pain, function and mechanical loads in knee osteoarthritis: a randomized controlled trial

Background: Recent studies have shown an important reduction of joint overload during locomotion in elderly women with knee osteoarthritis (OA) after short- term use of minimalist shoes. Our aim is to investigate the chronic effect of inexpensive and minimalist footwear on the clinical and functional aspects of OA and gait biomechanics of elderly women with knee OA. Methods/Design: Fifty-six elderly women with knee OA grade 2 or 3 (Kellgren and Lawrence) are randomized into blocks and allocated to either the intervention group, which will use flexible, non-heeled shoes-Moleca (R)-for six months for at least six hours daily, or the control group, which could not use these shoes. Neither group is undergoing physical therapy treatment throughout the intervention period. Moleca (R) is a women's double canvas, flexible, flat walking shoe without heels, with a 5-mm anti-slip rubber sole and a 3-mm internal wedge of ethylene vinyl acetate. Both groups will be followed for six months and will be assessed at baseline condition, after three months, and after six months (end of intervention). All the assessments will be performed by a physiotherapist that is blind to the group allocation. The primary outcome is the pain Western Ontario and McMaster Universities Osteoarthritis (WOMAC) score. The secondary outcomes are global WOMAC score; joint stiffness and disability WOMAC scores; knee pain with a visual analogue scale; walking distance in the six-minute walk test; Lequesne score; amount and frequency (number of days) of paracetamol (500 mg) intake over six months; knee adduction moment during gait; global medical assessment score; and global patient auto-assessment score. At baseline, all patients receive a diary to record the hours of daily use of the footwear intervention; every two weeks, the same physiotherapist makes phone calls to all patients in order to verify adherence to treatment. The statistical analysis will be based on intention to treat analysis, as well as general linear models of analysis of variance for repeated measure to detect treatment-time interactions (alpha = 5%). Discussion: This is the first randomized, clinical trial protocol to assess the chronic effect of minimalist footwear on the clinical and functional aspects and gait biomechanics of elderly women with knee osteoarthritis. We expect that the use of Moleca (R) shoes for six months will provide pain relief, reduction of the knee adduction moment when walking, and improve joint function in elderly women with knee OA, and that the treatment, thus, can be considered another inexpensive and easy-to-use option for conservative OA treatment.