Kicking the habit is hard: A hybrid choice model investigation into the role of addiction in smoking behavior

Use of choice models is growing rapidly in tobacco research. These models are being used to answer key policy questions. However, certain aspects of smokers' choice behavior are not well understood. One such feature is addiction. Here, we address this issue by modeling data from a choice experiment on the US smokers. We model addiction using a latent variable. We use this latent variable to understand the relationship between choices and addiction, giving attention to nicotine levels. We find that more addicted smokers have stronger preferences for cigarettes and are unwilling to switch to e‐cigarettes. Addicted smokers value nicotine in tobacco products to a much greater extent than those that are less addicted. Lastly, we forecast short‐term responses to lowering nicotine levels in cigarettes. The results suggest that current nicotine‐focused policies could be effective at encouraging addicted smokers to less harmful products and lead to substantial public health gains

Dynamical dispersion relation for ELKO dark spinor fields

An intrinsic mass generation mechanism for exotic ELKO dark matter fields is scrutinized, in the context of the very special relativity (VSR). Our results are reported on unraveling inequivalent spin structures that educe an additional term on the associated Dirac operator. Contrary to the spinor fields of mass dimension 3/2, this term is precluded to be absorbed as a shift of some gauge vector potential, regarding the equations for the dark spinor fields. It leads to some dynamical constraints that can be intrinsically converted into a dark spinor mass generation mechanism, with the encoded symmetries maintained by the VSR. The dynamical mass is embedded in the VSR framework through a natural coupling to the kink solution of a \lambda \phi^{4} theory for a scalar field \phi. Our results evince the possibility of novel effective scenarios, derived from exotic couplings among dark spinor fields and scalar field topological solutions.Comment: 6 pages, to appear in Phys.Lett.

Student and staff perceptions and experiences of the introduction of Objective Structured Practical Examinations: A pilot study

Background. The Objective Structured Practical Examination (OSPE) is widely recognised as one of the more objective methods of assessing practical skills in healthcare programmes, including undergraduate physiotherapy curricula.Objectives. To obtain feedback from both students and staff who were involved in the introduction of an OSPE in 2011, in order to refine and standardise the format throughout the curriculum.Methods. A qualitative research design was used. Data were gathered through a questionnaire with semi-structured open-ended items and focus group discussion. Participants were all third-year undergraduate physiotherapy students (N=47) and all staff members (N=10) in the 2011 academic year who were exposed to the OSPE format or were involved in the first OSPE.Results. The main concerns raised by both students and staff were: (i) pressure due to time constraints and how this might affect student performance; and (ii) the question of objectivity during the assessment. However, their initial concerns changed as they experienced the OSPE in a more positive manner owing to the structure and objectivity of the process of implementing the OSPE.Conclusion. While both students and staff reported positive experiences, the challenges that emerged provided valuable insight in terms of refining the OSPE format in this undergraduate physiotherapy department

Comportamento sedentário e obesidade abdominal em crianças e adolescentes : uma revisão sistemática

Orientadora : Neiva LeiteCoorientadora: Maiara Cristina TadiottoMonografia (licenciatura) - Universidade Federal do Paraná. Setor de Ciências Biológicas. Curso de Educação Físic

Long range molecular dynamics study of regulation of eukaryotic glucosamine-6-phosphate synthase activity by UDP-GlcNAc

Glucosamine-6-phosphate (GlcN-6-P) synthase catalyses the first and practically irreversible step in hexosamine metabolism. The final product of this pathway, uridine 5’ diphospho N-acetyl-D-glucosamine (UDP-GlcNAc), is an essential substrate for assembly of bacterial and fungal cell walls. Moreover, the enzyme is involved in phenomenon of hexosamine induced insulin resistance in type II diabetes, which makes it a potential target for antifungal, antibacterial and antidiabetic therapy. The crystal structure of the isomerase domain of GlcN-6-P synthase from human pathogenic fungus Candida albicans, in complex with UDP-GlcNAc has been solved recently but it has not revealed the molecular mechanism of inhibition taking place under UDP-GlcNAc influence, the unique feature of the eukaryotic enzyme. UDP-GlcNAc is a physiological inhibitor of GlcN-6-P synthase, binding about 1 nm away from the active site of the enzyme. In the present work, comparative molecular dynamics simulations of the free and UDP-GlcNAc-bounded structures of GlcN-6-P synthase have been performed. The aim was to complete static X-ray structural data and detect possible changes in the dynamics of the two structures. Results of the simulation studies demonstrated higher mobility of the free structure when compared to the liganded one. Several amino acid residues were identified, flexibility of which is strongly affected upon UDP-GlcNAc binding. Importantly, the most fixed residues are those related to the inhibitor binding process and to the catalytic reaction. The obtained results constitute an important step toward understanding of mechanism of GlcN-6-P synthase inhibition by UDP-GlcNAc molecule

The challenge of acute-stroke management: does telemedicine offer a solution?

<p><b>Background:</b> Several studies have described successful experiences with the use of telemedicine in acute stroke. The objective of this study was to assess the feasibility, acceptability, and treatment delivery reliability, of telemedicine systems for the clinical and radiological assessment, and management of acute-stroke patients.</p> <p><b>Summary of Review:</b> A systematic review of the literature was carried out. Studies were included if they met the following criteria: (1) study population included participants with a diagnosis of suspected acute stroke, (2) intervention included the use of telemedicine systems to aid assessment, diagnosis, or treatment in acute stroke, and (3) outcomes measured related to feasibility in clinical practice, acceptability to patients, carers, and staff, reliability of telemedicine systems, and effectiveness in delivering treatment, especially tissue plasminogen activator (tPA). Overall, 17 relevant non-randomised studies reported that telemedicine systems were feasible and acceptable. Interrater reliability was excellent for global clinical assessments and decisions on radiological exclusion criteria although agreement for individual assessment items was more variable. Telemedicine systems were associated with increased use of tPA.</p> <p><b>Conclusion:</b> Although there is limited reliable evidence, observational studies have indicated that telemedicine systems can be feasible, acceptable, and reliable in acute-stroke management. In addition, telemedicine consultations were associated with improved delivery of tPA.</p&gt

The geometry of a bi-Lagrangian manifold

This is a survey on bi-Lagrangian manifolds, which are symplectic manifolds endowed with two transversal Lagrangian foliations. We also study the non-integrable case (i.e., a symplectic manifold endowed with two transversal Lagrangian distributions). We show that many different geometric structures can be attached to these manifolds and we carefully analyse the associated connections. Moreover, we introduce the problem of the intersection of two leaves, one of each foliation, through a point and show a lot of significative examples.Comment: 30 page

DEVELOPMENT OF MODELS TO AID DECISION-MAKING IN THE MANAGEMENT OF Araucaria angustifolia (Bertol.) Kuntze

Operational research (OR) is a powerful tool for decision-making in optimizing forestry production planning. Thus, the objective of this study is to use the OR to solve forest regulation problems in a natural forest of Araucaria angustifolia (Bertol) Kuntze. The proposal for better management regime for the forest consisted in the elaboration of two OR problems using integer linear programming (ILP). I – the first aiming to maximize income for each regime; and the II – second aiming to define the best management alternative for three values of the De Liocourt q quotient of 1.1; 1.3 and 1.5, residual basal areas of 10.0, 12.0 and 14.0 m2.ha-1 and cutting cycles of 20, 25 and 30 years, creating thus 27 management scenarios. Despite the application of cutting cycles of 20, 25 and 30 years, the management alternative that best uses the resources and maximizes the income for this area of 84 ha, in the municipality of Lages, SC, is “q” = 1.3 with residual basal area of 12 m2.ha-1 for all cutting cycles. The removal of these trees in the forest will contribute to the maintenance of a future diametric structure, natural regeneration, species conservation and tree increment rate, as well as the maintenance of resources of the forest ecosystem.

Macroscopic transport by synthetic molecular machines

Nature uses molecular motors and machines in virtually every significant biological process, but demonstrating that simpler artificial structures operating through the same gross mechanisms can be interfaced with—and perform physical tasks in—the macroscopic world represents a significant hurdle for molecular nanotechnology. Here we describe a wholly synthetic molecular system that converts an external energy source (light) into biased brownian motion to transport a macroscopic cargo and do measurable work. The millimetre-scale directional transport of a liquid on a surface is achieved by using the biased brownian motion of stimuli-responsive rotaxanes (‘molecular shuttles’) to expose or conceal fluoroalkane residues and thereby modify surface tension. The collective operation of a monolayer of the molecular shuttles is sufficient to power the movement of a microlitre droplet of diiodomethane up a twelve-degree incline.

Analytical validation of an ultraviolet–visible procedure for determining vitamin D3 in vitamin D3-loaded microparticles and toxigenetic studies for incorporation into food

Vitamin D is a water-insoluble compound presented in two main forms (D2 and D3), susceptible to environmental conditions. Microencapsulation is an alternative to supplements and preserve vitamin D properties in foods. Entrapment efficiency (EE) is the main property to evaluate the encapsulation effectiveness and therefore it is of interest the study of analytical methods for the identification and quantification of this compound within the particle. This paper describes a low cost UV–Vis methodology validation to the identification and quantification of vitamin D3 in microparticles produced by hot homogenization. The method was validated following the International Conference on Harmonization (ICH) guidelines. To guarantee safe application in foodstuff, microparticles toxigenicity was evaluated with Allium cepa L. in vivo model, showing no cytotoxic nor genotoxic potential. High entrapment efficiency was obtained, the results also demonstrated that the concentration of vitamin D3 in microparticles can be safely accessed by the validated method.This study was financed in part by the Coordenaç˜ao de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. The authors thank the Multiuser Laboratory of Federal University of Technology – Paraná – Campus Londrina, and the “Central Analítica Multiusuário da UTFPR Campo Mourão” (CAMulti-CM) for the analyses. Also, to CNPq for the financial support (Project n◦ 420055/2018-5) and scholarship.info:eu-repo/semantics/publishedVersio