Parametric instability of the helical dynamo

We study the dynamo threshold of a helical flow made of a mean (stationary) plus a fluctuating part. Two flow geometries are studied, either (i) solid body or (ii) smooth. Two well-known resonant dynamo conditions, elaborated for stationary helical flows in the limit of large magnetic Reynolds numbers, are tested against lower magnetic Reynolds numbers and for fluctuating flows (zero mean). For a flow made of a mean plus a fluctuating part the dynamo threshold depends on the frequency and the strength of the fluctuation. The resonant dynamo conditions applied on the fluctuating (resp. mean) part seems to be a good diagnostic to predict the existence of a dynamo threshold when the fluctuation level is high (resp. low).Comment: 37 pages, 8 figure

Elaboration and TEM structural study of interfaces in composites produced by precipitation

Model ceramic matrix composites have been manufactured in a wide range of materials using the precipitation of a metal (Cu, Ni, Cr) in a ceramic matrix (nitride AIN or oxides MgO, Al2O3) providing, in each case low energy configurations at the heterophase interfaces. In connection to microelectronic applications, copper metallic particles precipitate in AIN after implantation by copper ions and anneal of the ceramic matrix. Faceted particles are imaged by HRTEM and are associated to a low energy structural and chemical configuration. Internal reduction experiments have been carried out on (Mg,Ni)O, (Mg,Cu)O and (Al,Cr)2O3 mixed oxides; the morphology, chemical composition and orientation relationship of the different precipitates are obtained through TEM observations and discussed in terms of interfacial energy and precipitate growth mechanism and kinetics. Conventional and high resolution TEM in conjonction to structural models have allowed a comprehensive description of the interface

Performance of Prototypes and Start up of Series Fabrication of the LHC Arc Quadrupoles

The construction of three prototype arc quadrupoles for the LHC machine has been concluded successfully. These magnets underwent warm and cold magnetic measurements as well as many other tests, both in CEA-Saclay's laboratory and at CERN. Their training qualifies them for use in the LHC machine and their measured field quality points to only very minor corrections. An excellent correlation is found between warm and cold magnetic measurements. The prototype quadrupole design has been fully retained for the series fabrication of the 400 magnets and their cold masses by industry. This paper describes the main tests and measurement results of all three prototypes. It further explains the logistics for the manufacturing of the series of cold masses. These cold masses contain not only the main quadrupole but also different combinations of corrector magnets. Thus, together with variants imposed by the cryogenic configuration of the machine, 40 different types of cold masses have to be fabricated by the firm, to which the contract has been adjudicated

Performance of Series-Design Prototype Main Quadrupoles for the LHC

After the successful construction of two first-generation prototypes of the main quadrupoles for the LHC, three series-design prototypes have been further manufactured at CEA-Saclay. Together with the sextupole-dipole corrector magnets and tuning quadrupoles, these twin-aperture main quadrupoles are assembled into the cold masses of the so-called short straight sections. Already during their fabrication, the collared coils and later the completed cold masses undergo warm magnetic measurements. Two of the main quadrupole cold masses have been mounted into their definitive machine cryostats and submitted to training and magnetic measurements. This paper presents the results of these cold tests by describing the quench behaviour, the transfer function in each of the apertures and the multipole components found at different levels of excitation. The field quality results, in cold conditions, will be compared to those measured at room temperatur

Challenging Social Cognition Models of Adherence:Cycles of Discourse, Historical Bodies, and Interactional Order

Attempts to model individual beliefs as a means of predicting how people follow clinical advice have dominated adherence research, but with limited success. In this article, we challenge assumptions underlying this individualistic philosophy and propose an alternative formulation of context and its relationship with individual actions related to illness. Borrowing from Scollon and Scollon’s three elements of social action – “historical body,” “interaction order,” and “discourses in place” – we construct an alternative set of research methods and demonstrate their application with an example of a person talking about asthma management. We argue that talk- or illness-related behavior, both viewed as forms of social action, manifest themselves as an intersection of cycles of discourse, shifting as individuals move through these cycles across time and space. We finish by discussing how these dynamics of social action can be studied and how clinicians might use this understanding when negotiating treatment with patients

Pretreatment, Psychological, and Behavioral Predictors of Weight Outcomes Among Lifestyle Intervention Participants in the Diabetes Prevention Program (DPP)

OBJECTIVE To identify the most important pretreatment characteristics and changes in psychological and behavioral factors that predict weight outcomes in the Diabetes Prevention Program (DPP). RESEARCH DESIGN AND METHODS Approximately 25% of DPP lifestyle intervention participants (n = 274) completed questionnaires to assess weight history and psychological and behavioral factors at baseline and 6 months after completion of the 16-session core curriculum. The change in variables from baseline to 6 months was assessed with t tests. Multivariate models using hierarchical logistic regression assessed the association of weight outcomes at end of study with each demographic, weight loss history, psychological, and behavioral factor. RESULTS At end of study, 40.5% had achieved the DPP 7% weight loss goal. Several baseline measures (older age, race, older age when first overweight, fewer self-implemented weight loss attempts, greater exercise self-efficacy, greater dietary restraint, fewer fat-related dietary behaviors, more sedentary activity level) were independent predictors of successful end-of-study weight loss with the DPP lifestyle program. The DPP core curriculum resulted in significant improvements in many psychological and behavioral targets. Changes in low-fat diet self-efficacy and dietary restraint skills predicted better long-term weight loss, and the association of low-fat diet self-efficacy with weight outcomes was explained by dietary behaviors. CONCLUSIONS Health care providers who translate the DPP lifestyle intervention should be aware of pretreatment characteristics that may hamper or enhance weight loss, consider prioritizing strategies to improve low-fat diet self-efficacy and dietary restraint skills, and examine whether taking these actions improves weight loss outcomes

The structure of Chariklo's rings from stellar occultations

Two narrow and dense rings (called C1R and C2R) were discovered around the Centaur object (10199) Chariklo during a stellar occultation observed on 2013 June 3. Following this discovery, we planned observations of several occultations by Chariklo's system in order to better characterize the physical properties of the ring and main body. Here, we use 12 successful occulations by Chariklo observed between 2014 and 2016. They provide ring profiles (physical width, opacity, edge structure) and constraints on the radii and pole position. Our new observations are currently consistent with the circular ring solution and pole position, to within the $\pm 3.3$ km formal uncertainty for the ring radii derived by Braga-Ribas et al. The six resolved C1R profiles reveal significant width variations from $\sim 5$ to 7.5 km. The width of the fainter ring C2R is less constrained, and may vary between 0.1 and 1 km. The inner and outer edges of C1R are consistent with infinitely sharp boundaries, with typical upper limits of one kilometer for the transition zone between the ring and empty space. No constraint on the sharpness of C2R's edges is available. A 1$\sigma$ upper limit of $\sim 20$ m is derived for the equivalent width of narrow (physical width <4 km) rings up to distances of 12,000 km, counted in the ring plane

Triplicity and Physical Characteristics of Asteroid (216) Kleopatra

To take full advantage of the September 2008 opposition passage of the M-type asteroid (216) Kleopatra, we have used near-infrared adaptive optics (AO) imaging with the W.M. Keck II telescope to capture unprecedented high resolution images of this unusual asteroid. Our AO observations with the W.M. Keck II telescope, combined with Spitzer/IRS spectroscopic observations and past stellar occultations, confirm the value of its IRAS radiometric radius of 67.5 km as well as its dog-bone shape suggested by earlier radar observations. Our Keck AO observations revealed the presence of two small satellites in orbit about Kleopatra (see Marchis et al., 2008). Accurate measurements of the satellite orbits over a full month enabled us to determine the total mass of the system to be 4.64+/-0.02 10^18 Kg. This translates into a bulk density of 3.6 +/-0.4 g/cm3, which implies a macroscopic porosity for Kleopatra of ~ 30-50%, typical of a rubble-pile asteroid. From these physical characteristics we measured its specific angular momentum, very close to that of a spinning equilibrium dumbbell.Comment: 35 pages, 3 Tables, 9 Figures. In press to Icaru

National Standards for Diabetes Self-Management Education

Diabetes self-management education (DSME) is a critical element of care for all people with diabetes and is necessary in order to improve patient outcomes. The National Standards for DSME are designed to define quality diabetes self-management education and to assist diabetes educators in a variety of settings to provide evidence-based education. Because of the dynamic nature of health care and diabetes-related research, these Standards are reviewed and revised approximately every 5 years by key organizations and federal agencies within the diabetes education community. A Task Force was jointly convened by the American Association of Diabetes Educators and the American Diabetes Association in the summer of 2006. Additional organizations that were represented included the American Dietetic Association, the Veteran's Health Administration, the Centers for Disease Control and Prevention, the Indian Health Service, and the American Pharmaceutical Association. Members of the Task Force included a person with diabetes; several health services researchers/behaviorists, registered nurses, and registered dietitians; and a pharmacist. The Task Force was charged with reviewing the current DSME standards for their appropriateness, relevance, and scientific basis. The Standards were then reviewed and revised based on the available evidence and expert consensus. The committee convened on 31 March 2006 and 9 September 2006, and the Standards were approved 25 March 2007

Probability of Achieving Glycemic Control with Basal Insulin in Patients with Type 2 Diabetes in Real-World Practice in the USA

Introduction: Basal insulin (BI) plays an important role in treating type 2 diabetes (T2D), especially when oral antidiabetic (OAD) medications are insufficient for glycemic control. We conducted a retrospective, observational study using electronic medical records (EMR) data from the IBM ® Explorys database to evaluate the probability of achieving glycemic control over 24 months after BI initiation in patients with T2D in the USA. Methods: A cohort of 6597 patients with T2D who started BI following OAD(s) and had at least one valid glycated hemoglobin (HbA1c) result recorded both within 90 days before and 720 days after BI initiation were selected. We estimated the changes from baseline in HbA1c every 6 months, the quarterly conditional probabilities of reaching HbA1c &lt; 7% if a patient had not achieved glycemic control prior to each quarter (Q), and the cumulative probability of reaching glycemic control over 24 months. Results: Our cohort was representative of patients with T2D who initiated BI from OADs in the USA. The average HbA1c was 9.1% at BI initiation, and decreased robustly (1.5%) in the first 6 months after initiation with no further reductions thereafter. The conditional probability of reaching glycemic control decreased rapidly in the first year (26.6% in Q2; 17.6% in Q3; 8.6% in Q4), and then remained low (≤ 6.1%) for each quarter in the second year. Cumulatively, about 38% of patients reached HbA1c &lt; 7% in the first year; only approximately 8% more did so in the second year. Conclusion: Our study of real-world data from a large US EMR database suggested that among patients with T2D who initiated BI after OADs, the likelihood of reaching glycemic control diminished over time, and remained low from 12 months onwards. Additional treatment options should be considered if patients do not reach glycemic control within 12 months of BI initiation. Funding: Sanofi Corporation. </p