Dimensional Crossover of Localisation and Delocalisation in a Quantum Hall Bar

The 2-- to 1--dimensional crossover of the localisation length of electrons confined to a disordered quantum wire of finite width $L_y$ is studied in a model of electrons moving in the potential of uncorrelated impurities. An analytical formula for the localisation length is derived, describing the dimensional crossover as function of width $L_y$, conductance $g$ and perpendicular magnetic field $B$ . On the basis of these results, the scaling analysis of the quantum Hall effect in high Landau levels, and the delocalisation transition in a quantum Hall wire are reconsidered.Comment: 12 pages, 7 figure

Complementary and alternative therapies for low back pain

The support for the principles of evidence-based medicine has increased within the field of complementary and alternative medicine (CAM). The objective of this chapter is to determine the effectiveness of CAM therapies compared to placebo, no intervention, or other interventions for acute/subacute and chronic non-specific low back pain (LBP). Results from Cochrane reviews on acupuncture, botanical medicine, massage, neuroreflexotherapy, and spinal manipulation have been used. The results showed that acupuncture is more effective than no treatment or sham treatment for chronic LBP but that there are no differences in effectiveness compared with other conventional therapies. Specific botanical medicines can be effective for acute episodes of chronic non-specific LBP in terms of short-term improvement in pain and functional status; long-term efficacy was not assessed. Massage seems more beneficial than sham treatment for chronic non-specific LBP but effectiveness compared with other conventional therapies is inconclusive. Neuroreflexotherapy appears to be more effective than sham treatment or standard care for chronic non-specific LBP. Spinal manipulation was more effective than sham manipulation or ineffective therapies, and equally effective as other conventional therapies. In summary, the results on CAM therapies for (acute episodes of) chronic LBP are promising but more evidence on the relative cost-effectiveness compared to conventional treatments is neede

Tea tree oil (Melaleuca alternifolia Maiden& Betche, Cheel) in control of Cercospora beticola Sacc. on Beet

Made available in DSpace on 2019-09-11T20:58:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2015RESUMO O óleo volátil da melaleuca (Melaleuca alternifolia Maiden & Betche, Cheel) possui atividade antimicrobiana podendo causar efeitos sobre as plantas. Avaliou-se a inibição do óleo em Cercospora beticolaSacc., e seu efeito no aumento da produção e qualidade de raízes de beterraba. As doses foram de 0,13; 0,67; 0,80 e 1,00% do óleo, além das testemunhas composta pelo meio de cultura Batata Dextrose Ágar (BDA) no experimento in vitro, e água no experimento in vivo. As plantas foram pulverizadas duas vezes por semana. O delineamento foi inteiramente casualizado, com 4 repetições, e as médias foram comparadas pelo teste Tukey a 5% de probabilidade. O índice de infecção das folhas foi determinado por escala diagramática além do peso e diâmetro das raízes. Os resultados de inibição do crescimento micelial para as doses do óleo foram 0; 56; 87; 83 e 99%, e os índices de infecção: 77,08; 35,62; 21,04; 19,37 e 20,00%, respectivamente, para a testemunha e as doses 0,13; 0,67; 0,80 e 1,00% do óleo. Somente na concentração de 0,80% o óleo proporcionou relação positiva entre o ganho de peso e o diâmetro das raízes. O óleo de Melaleuca foi eficaz no controle de C. beticola e, como consequência, houve produção de raízes de beterraba com melhor desenvolvimento.ABSTRACT The volatile oil from Melaleuca (Melaleuca alternifolia Maiden & Betche Cheel.) has antimicrobial properties and can promote several effects on plant cultivation. The aim of this study was to evaluate the inhibition of the oil in Cercospora beticola Sacc. and if it favors the growth and development of beet root. The doses were 0.13, 0.67, 0.8 and 1% of oil, besides the control PDA (potato-dextrose-agar) in vitro (laboratory condition) and with water as treatment control in vivo (field conditions). The plants were sprayed twice a week. The treatments were completely randomized and the averages were compared using the Tukey test at 5%. The infection rate of leaves was measured by diagrammatic scale besides the weight and diameter of tubers. The inhibition results of the radial growth by oil treatments were 0; 56, 87, 83 and 99%, while the infection rate showed: 77.08, 35.62, 21.04, 19.37 and 20% respectively to the control and to the oil concentration of 0,13; 0,67; 0,80 e 1,00%. Only at concentration of 0.8% the tea tree oil showed a positive relationship between tuber´s weight and tuber´s diameter gains. It can be concluded that tea tree oil is effective to controlling C. beticola, and also promotes an increase on development in beet tubers.[SOUZA, A.D.; ROGGERIO, T.U] Faculdade Integral Cantareira, BrazilFURLAN, M.R.] Universidade de Taubaté, BrazilAOYAMA, E.M.] Centro Universitário do Espírito Santo, Brazi

2009 updated method guidelines for systematic reviews in the Cochrane Back Review Group

STUDY DESIGN. Method guidelines for systematic reviews of trials of treatments for neck and back pain. OBJECTIVE. To help review authors design, conduct and report systematic reviews of trials in this field. SUMMARY OF BACKGROUND DATA. In 1997, the Cochrane Back Review Group published Method Guidelines for Systematic Reviews, which was updated in 2003. Since then, new methodologic evidence has emerged and standards have changed. Coupled with the upcoming revisions to the software and methods required by The Cochrane Collaboration, it was clear that revisions were needed to the existing guidelines. METHODS. The Cochrane Back Review Group editorial and advisory boards met in June 2006 to review the relevant new methodologic evidence and determine how it should be incorporated. Based on the discussion, the guidelines were revised and circulated for comment. As sections of the new Cochrane Handbook for Systematic Reviews of Interventions were made available, the guidelines were checked for consistency. A working draft was made available to review authors in The Cochrane Library 2008, issue 3. RESULTS. The final recommendations are divided into 7 categories: objectives, literature search, inclusion criteria, risk of bias assessment, data extraction, data analysis, and updating your review. Each recommendation is classified into minimum criteria (mandatory) and further guidance (optional). Instead of recommending Levels of Evidence, this update adopts the GRADE approach to determine the overall quality of the evidence for important patient-centered outcomes across studies and includes a new section on updating reviews. CONCLUSION. Citations of previous versions of the method guidelines in published scientific articles (1997: 254 citations; 2003: 209 citations, searched February 10, 2009) suggest that others may find these guidelines useful to plan, conduct, or evaluate systematic reviews in the field of spinal disorders. © 2009 Lippincott Williams & Wilkins, Inc

Evidence-informed management of chronic low back pain with needle acupuncture

Editors' preface: The management of chronic low back pain (CLBP) has proven to be very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing among available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to CLBP, the North American Spine Society has sponsored this special focus issue to The Spine Journal, titled Evidence-Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP. © 2008 Elsevier Inc. All rights reserved

Management Options for Patients with Chronic Back Pain without an Etiology

The treatment and management of low back pain is complex when there is no specific etiology such as cancer, fracture, or herniated disc. An organized approach to management that follows evidence based guidelines will facilitate care in a problem that reflects a lifetime prevalence of over 70 percent. The purpose of this review is to present a guideline to care for a common disabling process with a very heterogeneous etiology