Energy-based modelling of adhesive wear in the mixed lubrication regime

Adhesive wear in dry contacts is often described using the Archard or Fleischer model. Both provide equations for the determination of a wear volume, taking the load, the sliding path and a set of material parameters into account. While the Fleischer model is based on energetic approaches, the Archard formulation uses an empirical factor-the wear coefficient-describing the intensity of wear. Today, a numerical determination of the wear coefficient is already possible and both approaches can be deduced to a local accumulation of friction energy. The aim of this work is to enhance existing energy-based wear models into the mixed lubrication regime. Therefore, the pressure distribution within the contact area will be determined numerically taking real surface topographies into account. The emerging contact area will be divided into one part of solid and a second part of elastohydrodynamically lubricated (EHL) contacts. Based on the resulting pressure and shear stress distribution, the formation of micro cracks within the loaded volume will be described. Determining a critical number of load cycles for each asperity, a locally resolved wear coefficient will be derived and the local wear depth calculated

A mechanosensory receptor required for food texture detection in Drosophila.

Textural properties provide information on the ingestibility, digestibility and state of ripeness or decay of sources of nutrition. Compared with our understanding of the chemosensory assessment of food, little is known about the mechanisms of texture detection. Here we show that Drosophila melanogaster can discriminate food texture, avoiding substrates that are either too hard or too soft. Manipulations of food substrate properties and flies' chemosensory inputs indicate that texture preferences are revealed only in the presence of an appetitive stimulus, but are not because of changes in nutrient accessibility, suggesting that animals discriminate the substrates' mechanical characteristics. We show that texture preference requires NOMPC, a TRP-family mechanosensory channel. NOMPC localizes to the sensory dendrites of neurons housed within gustatory sensilla, and is essential for their mechanosensory-evoked responses. Our results identify a sensory pathway for texture detection and reveal the behavioural integration of chemical and physical qualities of food

A Comparison of Time-Memory Trade-Off Attacks on Stream Ciphers

Contains fulltext : 117176.pdf (preprint version ) (Open Access

The impact of participation in online cancer communities on patient reported outcomes:Systematic review

Background: In recent years, the question of how patients’ participating in online communities affects various patient reported outcomes (PROs) has been investigated in several ways. Objectives: This study aimed to systematically review all relevant literature identified using key search terms, with regard to, first, changes in PROs for cancer patients who participate in online communities and, second, the characteristics of patients who report such effects. Methods: A computerized search of the literature via PubMed (MEDLINE), PsycINFO (5 and 4 stars), Cochrane Central Register of Controlled Trials, and ScienceDirect was performed. Last search was conducted in June 2017. Studies with the following terms were included: (cancer patient) and (support group or health communities) and (online or Internet). A total of 21 studies were included and independently assessed by 2 investigators using an 11-item quality checklist. Results: The methodological quality of the selected studies varied: 12 were of high quality, eight were of adequate quality, and only one was of low quality. Most of the respondents were women (about 80%), most with breast cancer; their mean age was 50 years. The patients who were active in online support groups were mostly younger and more highly educated than the nonusers. The investigated PROs included general well-being (ie, mood and health), anxiety, depression, quality of life, posttraumatic growth, and cancer-related concerns. Only marginal effects—that is, PRO improvements—were found; in most cases they were insignificant, and in some cases they were contradictory. Conclusions: The main shortcoming of this kind of study is the lack of methodological instruments for reliable measurements. Furthermore, some patients who participate in online communities or interact with peers via Internet do not expect to measure changes in their PROs. If cancer survivors want to meet other survivors and share information or get support, online communities can be a trustworthy and reliable platform to facilitate opportunities or possibilities to make this happen. Keywords: cancer; survivors; patient reported outcomes; Internet; support group

Exploring the relationship among dispositional optimism, health-related quality of life, and CIPN severity among colorectal cancer patients with chronic peripheral neuropathy

Purpose. Chemotherapy-induced peripheral neuropathy ((CI)PN) becomes chronic in 30% of cancer patients. Knowledge of predictors of chronic (CI)PN and related impairments in health-related quality of life (HRQoL) is lacking. We examined the role of optimism in chronic (CI)PN severity and associated HRQoL in colorectal cancer (CRC) patients up to two years after diagnosis. Methods. CRC patients from a prospective cohort study participated, with sensory peripheral neuropathy (SPN) 1 year after diagnosis (n = 142). Multivariable regression analyses examined the cross-sectional association between optimism (measured by the LOT-R) and SPN severity/HRQoL (measured by the EORTC QLQ-CIPN20 and QLQ-C30), as well as the prospective association in a subsample that completed measures 2 years after diagnosis and still experienced SPN (n = 86). Results. At 1-year follow-up, higher optimism was associated with better global HRQoL, and better physical, role, emotional, cognitive, and social functioning (all p < .01). Optimism at year one was also prospectively associated with better global HRQoL (p < .05), and emotional and cognitive functioning at 2-year follow-up (both p < .01). Optimism was not related to self-reported SPN severity. Significant associations were retained when controlling for demographic/clinical variables, and became non-significant after controlling for depressive and anxiety symptoms. Conclusions. Optimism and depressive and anxiety symptoms are associated with HRQoL in CRC patients with chronic (CI)PN. Future research may illuminate the mechanisms that these factors share, like the use of (non)adaptive coping styles such as avoidance and acceptance that may inform the design of targeted interventions to help patients to adapt to chronic (CI)PN