Effects of different Incentives on Attrition and Fieldwork Effort in Telephone Household Panel Surveys

Little is known about sample behavior and fieldwork effects of different incentives introduced in a household panel survey. This is especially true for telephone surveys. In a randomized experiment, the Swiss Household Panel implemented one prepaid and two promised nonmonetary incentives in the range of 10 to 15 Swiss Francs (7-10 e), plus a no incentive control group. The aim of the paper is to compare effects of these incentives especially on cooperation, but also on sample selection and fieldwork effort, separated by the household and the subsequent individual level. We find small positive cooperation effects of the prepaid incentive on both the household and the individual level especially in larger households. Sample composition is affected to a very minor extent. Finally, incentives tend to save fieldwork time and partially the number of contacts needed on the individual level.

The efficacy of melatonin for sleep problems in children with autism, fragile X syndrome, or autism and fragile X syndrome.

STUDY OBJECTIVE: To determine the efficacy of melatonin on sleep problems in children with autistic spectrum disorder (ASD) and fragile X syndrome (FXS). METHODS: A 4-week, randomized, double blind, placebo-controlled, crossover design was conducted following a 1-week baseline period. Either melatonin, 3 mg, or placebo was given to participants for 2 weeks and then alternated for another 2 weeks. Sleep variables, including sleep duration, sleep-onset time, sleep-onset latency time, and the number of night awakenings, were recorded using an Actiwatch and from sleep diaries completed by parents. All participants had been thoroughly assessed for ASD and also had DNA testing for the diagnosis of FXS. RESULTS: Data were successfully obtained from the 12 of 18 subjects who completed the study (11 males, age range 2 to 15.25 years, mean 5.47, SD 3.6). Five participants met diagnostic criteria for ASD, 3 for FXS alone, 3 for FXS and ASD, and 1 for fragile X premutation. Eight out of 12 had melatonin first. The conclusions from a nonparametric repeated-measures technique indicate that mean night sleep duration was longer on melatonin than placebo by 21 minutes (p = .02), mean sleep-onset latency was shorter by 28 minutes (p = .0001), and mean sleep-onset time was earlier by 42 minutes (p = .02). CONCLUSION: The results of this study support the efficacy and tolerability of melatonin treatment for sleep problems in children with ASD and FXS.

Identification of schistosome-infected snails by detecting schistosomal antigens and DNA sequences

Cercarial shedding tests do not provide species identification of the shistosomes concerned and cannot detect prepatent schistosomal infections. We have demonstrated that both immunodetection by ELISA of schistosomal antigens in snail hemophlymph, and dot hybridization of snail extracts by DNA probe representing highly repeated sequences, proved suitable for detecting infected snails during prepatnecy as well as patency. A group-specific monoclonal antibody was found to be suitable for detecting Schistosoma mansoni infection in Biomphalaria sp., but not for positive identification of S. haematobium in Blulinus sp. Comparative evaluation of the diagnostic qualities, and technical aspects and cost of these tests, point to the superiority of the immunodetection approach for large scale detection of snails prepatently infected with S. mansoni. This approach is potentially useful for providing extended information on schistosome-snail epidemiology that may facilitate rapid evaluation of the danger of post-control reinfection, and help make decisions on the time and place of supplementary control measures. In this context the potential usefulness of the immunodetection or DNA probing approach for facilitating catalytic model representation of schistosome-snail epidemiology warrants further evaluation. Specific identification of S. haematobium in Bulinus by either of these approaches may be possible depending on the development of suitable antibodies or DNA probes.

A collaborative approach for incorporating forensic case data into crime investigation using criminal intelligence analysis and visualisation

There is an increasing awareness that the articulation of forensic science and criminal investigation is critical to the resolution of crimes. However, models and methods to support an effective collaboration between these partners are still poorly expressed or even lacking. Three propositions are borrowed from crime intelligence methods in order to bridge this gap: (a) the general intelligence process, (b) the analyses of investigative problems along principal perspectives: entities and their relationships, time and space, quantitative aspects and (c) visualisation methods as a mode of expression of a problem in these dimensions. Indeed, in a collaborative framework, different kinds of visualisations integrating forensic case data can play a central role for supporting decisions. Among them, link-charts are scrutinised for their abilities to structure and ease the analysis of a case by describing how relevant entities are connected. However, designing an informative chart that does not bias the reasoning process is not straightforward. Using visualisation as a catalyser for a collaborative approach integrating forensic data thus calls for better specifications.

Behavior study of pipes after forming, coating and bending

A study of the main types of coatings and its processes that modern industry commonly apply to prevent to the corrosion due to the environmental effects to energetic market pipelines have been done. Extracting main time and temperature range values, coating heat treatment recreation have been applied to x65 pipelines steel grade samples obtained from a pipe which was formed using UOE forming process. Experimental tensile tests and Charpy V‐Notch Impact test have been carried out for a deeply knowledge of the influence on the steel once this recreations are applied. The Yield Strength and toughness have been improved despite lower values in rupture strain and ductile‐brittle temperature transition have been obtained. Finite Element Method have been applied to simulate the entirely pipe cold bending process to predict the mechanical properties and behaviour of the pipe made from x65 steel grade under different conditions.

As the world turns: short-term human spatial memory in egocentric and allocentric coordinates

We aimed to determine whether human subjects' reliance on different sources of spatial information encoded in different frames of reference (i.e., egocentric versus allocentric) affects their performance, decision time and memory capacity in a short-term spatial memory task performed in the real world. Subjects were asked to play the Memory game (a.k.a. the Concentration game) without an opponent, in four different conditions that controlled for the subjects' reliance on egocentric and/or allocentric frames of reference for the elaboration of a spatial representation of the image locations enabling maximal efficiency. We report experimental data from young adult men and women, and describe a mathematical model to estimate human short-term spatial memory capacity. We found that short-term spatial memory capacity was greatest when an egocentric spatial frame of reference enabled subjects to encode and remember the image locations. However, when egocentric information was not reliable, short-term spatial memory capacity was greater and decision time shorter when an allocentric representation of the image locations with respect to distant objects in the surrounding environment was available, as compared to when only a spatial representation encoding the relationships between the individual images, independent of the surrounding environment, was available. Our findings thus further demonstrate that changes in viewpoint produced by the movement of images placed in front of a stationary subject is not equivalent to the movement of the subject around stationary images. We discuss possible limitations of classical neuropsychological and virtual reality experiments of spatial memory, which typically restrict the sensory information normally available to human subjects in the real world.

Oxidative potential of a panel of carbonaceous and metallic nanoparticles

Characterisation of nanoparticles (NP) based on size distribution, surface area, reactivity, and aggregation status of nanoparticles (NP) are of prime importance because they are usually closely related to toxicity. To date, most of the toxicity studies are quite time and money consuming. In the present study we report the oxidative properties of a panel of various NP (four Carbonaceous, nine Metal oxides, and one Metal as showed in Table 1) assessed with an acellular reactivity test measuring dithiothreitol (DTT) consumption (Sauvain et al. 2008). Such a test allows determining the ability of NP to catalyse the transfer of electrons from DTT to oxygen. DTT is used as a reductant species. NP were diluted and sonicated in Tween 80® to a final concentration of 50 g/mL. Printex 90 was diluted 5 times before doing the DTT assay because of its expected higher activity. Suspensions were characterised for NP size distribution by Nanoparticle Tracking Analysis (Nanosight©). Fresh solutions were incubated with DTT (100 μM). Aliquots were taken every 5 min and the remaining DTT was determined by reacting it with DTNB. The reaction rate was determined for NP suspensions and blank in parallel. The mean Brownian size distribution of NP agglomerates in suspension is presented in Table 1. D values correspond to 10th, and 50th percentiles of the particle diameters. All the NP agglomerated in Tween 80 with a D50 size corresponding to at least twice their primary size, except for Al2O3 (300 nm). The DTT test showed Printex 90 sample to be the most reactive one, followed by Diesel EPA and Nanotubes. Most of the metallic NP was nonresponding toward this test, except for NiO and Ag which reacted positively and ZnO which presented the most negative reactivity (see Figure 1). This last observation suggests that electron transfer between DTT and oxygen is hindered in presence of ZnO compared with the blank. Such "stabilization" could be attributable to ZnO dissolution and complexation between Zn2+ ions and DTT.

Theoretical estimates of consumable food and probability of acquiring food in larvae of Chrysomya putoria (Diptera: Calliphoridae)

An indirect estimate of consumable food and probability of acquiring food in a blowfly species, Chrysomya putoria, is presented. This alternative procedure combines three distinct models to estimate consumable food in the context of the exploitative competition experienced by immature individuals in blowfly populations. The relevant parameters are derived from data for pupal weight and survival and estimates of density-independent larval mortality in twenty different larval densities. As part of this procedure, the probability of acquiring food per unit of time and the time taken to exhaust the food supply are also calculated. The procedure employed here may be valuable for estimations in insects whose immature stages develop inside the food substrate, where it is difficult to partial out confounding effects such as separation of faeces. This procedure also has the advantage of taking into account the population dynamics of immatures living under crowded conditions, which are particularly characteristic of blowflies and other insects as well.

Physicians' attitudes towards prevention: importance of intervention-specific barriers and physicians' health habits.

BACKGROUND: Several studies have explored physicians' attitudes towards prevention and barriers to the delivery of preventive health interventions. However, the relative importance of these previously identified barriers, both in general terms and in the context of a number of specific preventive interventions, has not been identified. Certain barriers may only pertain to a subset of preventive interventions. OBJECTIVES: We aimed to determine the relative importance of identified barriers to preventive interventions and to explore the association between physicians' characteristics and their attitudes towards prevention. METHODS: We conducted a cross-sectional survey of 496 of the 686 (72.3% response rate) generalist physicians from three Swiss cantons through a questionnaire asking physicians to rate the general importance of eight preventive health strategies and the relative importance of seven commonly cited barriers in relation to each specific preventive health strategy. RESULTS: The proportion of physicians rating each preventive intervention as being important varied from 76% for colorectal cancer screening to 100% for blood pressure control. Lack of time and lack of patient interest were generally considered to be important barriers by 41% and 44% of physicians, respectively, but the importance of these two barriers tended to be specifically higher for counselling-based interventions. Lack of training was most notably a barrier to counselling about alcohol and nutrition. Four characteristics of physicians predicted negative attitudes toward alcohol and smoking counselling: consumption of more than three alcoholic drinks per day [odds ratio (OR) = 8.4], sedentary lifestyle (OR = 3.4), lack of national certification (OR = 2.2) and lack of awareness of their own blood pressure (OR = 2.0). CONCLUSIONS: The relative importance of specific barriers varies across preventive interventions. This points to a need for tailored practice interventions targeting the specific barriers that impede a given preventive service. The negative influence of physicians' own health behaviours indicates a need for associated population-based interventions that reduce the prevalence of high-risk behaviours in the population as a whole.

Minimal clinically meaningful differences for the eortc QLQ-C30 and eortc QLQ-Bn20 scales in brain cancer patients

Objective: The aim of this study was to determine the smallest changes in health-related quality of life (HRQOL) scores in the European Organization for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) and the EORTC Brain Cancer Module (QLQ-BN20), which could be considered as clinically meaningful in brain cancer patients. Methods: World Health Organization (WHO) performance status (PS) and the Mini Mental State Examination (MMSE) were used as clinical anchors to determine minimal clinically important differences (MCID) in HRQOL change scores (range 0 - 100) in the EORTC QLQ-C30 and QLQ-BN20. Anchor-based MCID estimates less than 0.2SD (small effect) were not recommended for interpretation. Other selected distribution-based methods were also used for comparison purposes. Results: Based on WHO PS, our findings support the following whole number estimates of the MCID for improvement and deterioration respectively: physical functioning (6, 9), role functioning (14, 12), cognitive functioning (8, 8), global health status (7, 4*), fatigue (12, 9) and motor dysfunction (4*, 5). Anchoring with MMSE, cognitive functioning MCID estimates for improvement and deterioration were (11, 2*) and those for communication deficit were (9, 7). The estimates with asterisks were less that the set 0.2 SD threshold and are therefore not recommended for interpretation. Our MCID estimates therefore range from 5-14. Conclusion: These estimates can help clinicians to evaluate changes in HRQOL over time and, in conjunction with other measures of efficacy, help to assess the value of a health care intervention or to compare treatments. Furthermore, the estimates can be useful in determining sample sizes in the design of future clinical trials.

Change in individual growth rate and its link to gill-net fishing in two sympatric whitefish species

Size-selective fishing is expected to affect traits such as individual growth rate, but the relationship between the fishery-linked selection differentials and the corresponding phenotypic changes is not well understood. We analysed a 25-year monitoring survey of sympatric populations of the two Alpine whitefish Coregonus albellus and C. fatioi. We determined the fishing-induced selection differentials on growth rates, the actual change of growth rates over time, and potential indicators of reproductive strategies that may change over time. We found marked declines in adult growth rate and significant selection differentials that may partly explain the observed declines. However, when comparing the two sympatric species, the selection differentials on adult growth were stronger in C. albellus while the decline in adult growth rate seemed more pronounced in C. fatioi. Moreover, the selection differential on juvenile growth was significant in C. albellus but not in C. fatioi, while a significant reduction in juvenile growth over the last 25 years was only found in C. fatioi. Our results suggest that size-selective fishing affects the genetics for individual growth in these whitefish, and that the link between selection differentials and phenotypic changes is influenced by species-specific factors.

Body mass index: comparing mean values and prevalence rates from telephone and examination surveys.

BACKGROUND: Cost effective means of assessing the levels of risk factors in the population have to be defined in order to monitor these factors over time and across populations. This study is aimed at analyzing the difference in population estimates of the mean levels of body mass index (BMI) and the prevalences of overweight, between health examination survey and telephone survey. METHODS: The study compares the results of two health surveys, one by telephone (N=820) and the other by physical examination (N=1318). The two surveys, based on independent random samples of the population, were carried out over the same period (1992-1993) in the same population (canton of Vaud, Switzerland). RESULTS: Overall participation rates were 67% and 53% for the health interview survey (HIS) and the health examination survey (HES) respectively. In the HIS, the reporting rate was over 98% for weight and height values. Self-reported weight was on average lower than measured weight, by 2.2 kg in men and 3.5 kg in women, while self-reported height was on average greater than measured height, by 1.2 cm in men and 1.9 cm in women. As a result, in comparison to HES, HIS led to substantially lower mean levels of BMI, and to a reduction of the prevalence rates of obesity (BMI>30 kg/m(2)) by more than a half. These differences are larger for women than for men. CONCLUSION: The two surveys were based on different sampling procedures. However, this difference in design is unlikely to explain the systematic bias observed between self-reported and measured values for height and weight. This bias entails the overall validity of BMI assessment from telephone surveys.

Frequency and determinants of unprotected sex among HIV-infected persons: the Swiss HIV cohort study.

BACKGROUND: Access to antiretroviral therapy may have changed condom use behavior. In January 2008, recommendations on condom use for human immunodeficiency virus (HIV)-positive persons were published in Switzerland, which allowed for unprotected sex under well-defined circumstances ("Swiss statement"). We studied the frequency, changes over time, and determinants of unprotected sex among HIV-positive persons. METHODS: Self-reported information on sexual preference, sexual partners, and condom use was collected at semi-annual visits in all participants of the prospective Swiss HIV Cohort Study from April 2007 through March 2009. Multivariable logistic regression models were fit using generalized estimating equations to investigate associations between characteristics of cohort participants and condom use. FINDINGS: A total of 7309 participants contributed to 21,978 visits. A total of 4291 persons (80%) reported sexual contacts with stable partners, 1646 (30%) with occasional partners, and 557 (10%) with stable and occasional partners. Of the study participants, 5838 (79.9%) of 7309 were receiving antiretroviral therapy, and of these, 4816 patients (82%) had a suppressed viral load. Condom use varied widely and differed by type of partner (visits with stable partners, 10,368 [80%] of 12,983; visits with occasional partners, 4300 [88%] of 4880) and by serostatus of stable partner (visits with HIV-negative partners, 7105 [89%] of 8174; visits with HIV-positive partners, 1453 [48%] of 2999). Participants were more likely to report unprotected sex with stable partners if they were receiving antiretroviral therapy, if HIV replication was suppressed, and after the publication of the "Swiss statement." Noninjection drug use and moderate or severe alcohol use were associated with unprotected sex. CONCLUSIONS: Antiretroviral treatment and plasma HIV RNA titers influence sexual behavior of HIV-positive persons. Noninjection illicit drug and alcohol use are important risk factors for unprotected sexual contacts.

Giacomo Becattini and the Marshall's method. A Schumpeterian approach

The studies of Giacomo Becattini concerning the notion of the "Marshallian industrial district" have led a revolution in the field of economic development around the world. The paper offers an interpretation of the methodology adopted by Becattini. The roots are clearly Marshallian. Becattini proposes a return to the economy as a complex social science that operates in historical time. We adopt a Schumpeterian approach to the method in economic analysis in order to highlight the similarities between the Marshall and Becattini's approach. Finally the paper uses the distinction between logical time, real time and historical time which enable us to study the "localized" economic process in a Becattinian way.

Lufaxin, a novel factor Xa inhibitor from the salivary gland of the sand fly Lutzomyia longipalpis blocks protease-activated receptor 2 activation and inhibits inflammation and thrombosis in vivo.

OBJECTIVE: Blood-sucking arthropods' salivary glands contain a remarkable diversity of antihemostatics. The aim of the present study was to identify the unique salivary anticoagulant of the sand fly Lutzomyia longipalpis, which remained elusive for decades. METHODS AND RESULTS: Several L. longipalpis salivary proteins were expressed in human embryonic kidney 293 cells and screened for inhibition of blood coagulation. A novel 32.4-kDa molecule, named Lufaxin, was identified as a slow, tight, noncompetitive, and reversible inhibitor of factor Xa (FXa). Notably, Lufaxin's primary sequence does not share similarity to any physiological or salivary inhibitors of coagulation reported to date. Lufaxin is specific for FXa and does not interact with FX, Dansyl-Glu-Gly-Arg-FXa, or 15 other enzymes. In addition, Lufaxin blocks prothrombinase and increases both prothrombin time and activated partial thromboplastin time. Surface plasmon resonance experiments revealed that FXa binds Lufaxin with an equilibrium constant ≈3 nM, and isothermal titration calorimetry determined a stoichiometry of 1:1. Lufaxin also prevents protease-activated receptor 2 activation by FXa in the MDA-MB-231 cell line and abrogates edema formation triggered by injection of FXa in the paw of mice. Moreover, Lufaxin prevents FeCl(3)-induced carotid artery thrombus formation and prolongs activated partial thromboplastin time ex vivo, implying that it works as an anticoagulant in vivo. Finally, salivary gland of sand flies was found to inhibit FXa and to interact with the enzyme. CONCLUSIONS: Lufaxin belongs to a novel family of slow-tight FXa inhibitors, which display antithrombotic and anti-inflammatory activities. It is a useful tool to understand FXa structural features and its role in prohemostatic and proinflammatory events.