Determination of recovery effort for a probabilistic recovery system under various inventory control policies

In this study we investigate the desired level of recovery under various inventory control policies when the success of recovery is probabilistic. All the used and returned items go into a recovery process that is modelled as a single stage operation. The recovery effort is represented by the expected time spent for it. The effect of increasing recovery effort on the success probability together with unit cost of the operation is included by assuming general forms of dependencies. Alternative to recovered items, demand is satisfied by brand-new items. Four inventory control policies that differ in timing of and information used in purchasing decision are proposed. The objective is to find the recovery level together with inventory control parameter that minimize the long-run average total cost. A numerical study covering a wide range of system parameters is carried out. Finally computational results are presented with their managerial implications.     

‘Democracy always comes first’: adolescents’ views on decision-making in everyday life and political democracy

Research shows adolescents to be positively oriented towards democracy, but little is known about what it actually means to them and what their views are on decision-making in both everyday situations and political democracy. To gain insight into these aspects of adolescents’ democratic views, we have interviewed 40 Dutch adolescents from second grade of different types of high school. Potential conflict between various democratic principles prevalent in everyday life situations was discussed and compared to how they view decision-making in political democracy. The results of our qualitative study showed that adolescents’ views on issues concerning collective decision-making in everyday situations are quite rich and reflect different models of democracy (majoritarian, consensual, and deliberative). Moreover, how adolescents deal with tensions between democratic principles in everyday life situations varies. While some adolescents combine several principles (for instance, majority rule as a last resort after trying to find broader consensus), other adolescents tend to strictly focus on only one of these principles. Adolescents’ views on political democracy, however, are rather limited and one-dimensional. Those adolescents who seemed to have a more explicit picture of political democracy often preferred a strict focus on majority rule, neglecting minority interests.     

Modeling the Adenoma and Serrated Pathway to Colorectal CAncer (ASCCA)

Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC.     

Insight into Informant Discrepancies Regarding Psychosexual Functioning of Adolescents with and without Autism Spectrum Disorder

The private nature of psychosexual functioning leads adolescents and their parents to have different perspectives, which highlights studying parent–child informant discrepancies in this domain. We investigated informant discrepancy in psychosexual functioning, using the self‐report and parent report versions of the Teen Transition Inventory (TTI), of adolescents with autism spectrum disorder (ASD; 136 parent–child dyads) compared to adolescents from the general population (GP; 70 parent–child dyads). Significantly larger informant discrepancies exist in ASD dyads than GP dyads in most domains of psychosexual functioning, except for Body image, Sexual behavior, and Confidence in the future. It is important to use and pay attention to both informants, as discrepancies are relevant for both research and clinical practice regarding psychosexual functioning.     

Dissolution of Associational Life? Testing the Individualization and Informalization Hypotheses on Leisure Activities in The Netherlands Between 1975 and 2005

In this paper we examine whether individualization and informalization processes have occurred in the field of leisure in The Netherlands, by analyzing the social context of a wide range of activities between 1975 and 2005. We find that the choice of a particular leisure context is dependent on education, gender, year of birth, age and time pressure. We find evidence for informalization, but—contrary to popular belief—not for individualization. The informalization trend follows a pattern of cohort replacement, and is also caused by a rise in the average education level in the population. Our findings imply that research on civil society, community and social capital should not only be concerned with membership rates, but also with participation in alternative social contexts.     

Rate of Foot-and-Mouth Disease Virus Transmission by Carriers Quantified from Experimental Data

Upon infection with foot-and-mouth disease virus (FMDV) a considerable number of animals become carriers of the virus. These carriers are considered to be a risk for new outbreaks, but the rate at which these animals can transmit the infection has not been quantified. An analysis was carried out using data from previously published experiments in order to quantify the transmission rate parameter β of FMDV infection from carriers to susceptible animals. The parameter β was estimated at 0.0256 (likelihood-based confidence interval: 0.008–0.059) infections per carrier per month. Moreover, analysis of published experimental data indicates that the proportion of FMDV carriers decreases at a rate of 0.115 per month. Both parameters obtained from this study are useful for quantitative risk analyses of the trade of animals from FMDV-infected areas or the lifting of vaccination programs.     

A characterisation of logistics networks for product recovery

Recovery of used products is receiving much attention recently due to growing environmental concern. Efficient implementation requires appropriate logistics structures to be set up for the arising goods flow from users to producers. We investigate the design of such logistics networks. As a basis for our analysis we review recent case studies on logistics network design for product recovery in different industries. We identify general characteristics of product recovery networks and compare them with traditional logistics structures. Moreover, we derive a classification scheme for different types of recovery networks.     

Video-Based Eye Tracking in Sex Research: A Systematic Literature Review

Although eye tracking has been used for decades, it has gained popularity in the area of sex research only recently. The aim of this article is to examine the potential merits of eye tracking for this field. We present a systematic review of the current use of video-based eye-tracking technology in this area, evaluate the findings, and identify future research opportunities. A total of 34 relevant studies published between 2006 and 2014 were identified for inclusion by means of online databases and other methods. We grouped them into three main areas of research: body perception and attractiveness, forensic research, and sexual orientation. Despite the methodological and theoretical differences across the studies, eye tracking has been shown to be a promising tool for sex research. The article suggests there is much potential for further studies to employ this technique because it is noninvasive and yet still allows for the assessment of both conscious and unconscious perceptional processes. Furthermore, eye tracking can be implemented in investigations of various theoretical backgrounds, ranging from biology to the social sciences.