A molecular dynamics boundary condition for heat exchange between walls and a fluid

In molecular dynamics simulations of heat transfer in micro channels, a lot of computation time is used when the wall molecules are explicitly simulated. To save computation time, implicit boundary conditions, such as the Maxwell conditions, can be used. With these boundary conditions, heat transfer is still a problem. In this work, we derive a new boundary condition based on a vibrating potential wall. The heat-transfer properties of the new boundary condition are shown to be comparable with those of the explicit wall. The computation time needed for the implicit boundary condition is very small compared with that needed for the explicit simulation

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IMPORTANCE The cost of bilateral cochlear implantation (BCI) is usually not reimbursed by insurance companies because of a lack of well-designed studies reporting the benefits of a second cochlear implant. OBJECTIVE To determine the benefits of simultaneous BCI compared with unilateral cochlear implantation (UCI) in adults with postlingual deafness. DESIGN, SETTING, AND PARTICIPANTS A multicenter randomized clinical trial was performed. The study took place in 5 Dutch tertiary referral centers: the University Medical Centers of Utrecht, Maastricht, Groningen, Leiden, and Nijmegen. Forty patients eligible for cochlear implantation met the study criteria and were included from January 12, 2010, through November 2, 2012. The main inclusion criteria were postlingual onset of hearing loss, age of 18 to 70 years, duration of hearing loss of less than 20 years, and a marginal hearing aid benefit. Two participants withdrew from the study before implantation. Nineteen participants were randomized to undergo UCI and 19 to undergo BCI. INTERVENTIONS The BCI group received 2 cochlear implants during 1 surgery. The UCI group received 1 cochlear implant. MAIN OUTCOMES AND MEASURES The primary outcome was the Utrecht Sentence Test with Adaptive Randomized Roving levels (speech in noise, both presented from straight ahead). Secondary outcomes were consonant-vowel-consonant words in silence, speech-intelligibility test with spatially separated sources (speech in noise from different directions), sound localization, and quality of hearing questionnaires. Before any data were collected, the hypothesis was that the BCI group would perform better on the objective and subjective tests that concerned speech intelligibility in noise and spatial hearing. RESULTS Thirty-eight patients were included in the study. Fifteen patients in the BCI group used hearing aids before implantation compared with 19 in the UCI group. Otherwise, there were no significant differences between the groups' baseline characteristics. At 1-year follow-up, there were no significant differences between groups on the Utrecht Sentence Test with Adaptive Randomized Roving levels (9.1 dB, UCI group; 8.2 dB, BCI group; P = .39) or the consonant-vowel-consonant test (median percentage correct score 85.0% in the UCI group and 86.8% in the BCI group; P = .21). The BCI group performed significantly better than the UCI group when noise came from different directions (median speech reception threshold in noise, 14.4 dB, BCI group; 5.6 dB, BCI group; P <.001). The BCI group was better able to localize sounds (median correct score of 50.0% at 60 degrees, UCI group; 96.7%, BCI group; P CONCLUSIONS AND RELEVANCE This randomized clinical trial demonstrates a significant benefit of simultaneous BCI above UCI in daily listening situations for adults with postlingual deafness

Temperature and surgical wound heat loss during orthopedic surgery: computer simulations and measurements

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Cognitive radio network in vehicular ad hoc network (VANET): a survey

Cognitive radio network and vehicular ad hoc network (VANET) are recent emerging concepts in wireless networking. Cognitive radio network obtains knowledge of its operational geographical environment to manage sharing of spectrum between primary and secondary users, while VANET shares emergency safety messages among vehicles to ensure safety of users on the road. Cognitive radio network is employed in VANET to ensure the efficient use of spectrum, as well as to support VANET’s deployment. Random increase and decrease of spectrum users, unpredictable nature of VANET, high mobility, varying interference, security, packet scheduling, and priority assignment are the challenges encountered in a typical cognitive VANET environment. This paper provides survey and critical analysis on different challenges of cognitive radio VANET, with discussion on the open issues, challenges, and performance metrics for different cognitive radio VANET applications

Hair follicle bulge cultures yield class III β-tubulin-positive melanoglial cells

Class III β-tubulin (TUBB3)-positive cells from the hair follicle bulge are thought to be neuronal cells derived from a local neural crest stem cell. However, TUBB3 has recently been shown to be expressed in the melanocytic lineage. To evaluate the neural-crest-associated immunophenotype of TUBB3-positive cells from hair follicle bulge explants, we dissected hair follicle bulges out from mouse whisker pads and cultured for 1 month and assessed outgrowing cells by means of immunocytochemistry using the biomarkers TUBB3, nestin, NGFR, SOX9, TYRP1 and laminin. Large amounts of TUBB3-positive cells could be cultured that co-expressed nestin, NGFR, SOX9 and, to a lesser degree, TYRP1, matching a melanoglial phenotype. In addition, a small population of TUBB3-negative but laminin-positive cells was found, which presumably are of glial origin. It can be concluded that cells of melanoglial origin can easily be obtained from hair follicle bulge explants. These cells may be of use in experimental animal or human disease and wound healing models. Notably, the TUBB3-positive cells are of melanoglial rather than neuronal origin

The adaptiveness in stock markets: testing the stylized facts in the DAX 30

© 2017, Springer-Verlag Berlin Heidelberg. By testing a simple asset pricing model of heterogeneous agents to characterize the power-law behavior of the DAX 30 from 1975 to 2007, we provide supporting evidence on empirical findings that investors and fund managers use combinations of fixed and switching strategies based on fundamental and technical analysis when making investment decisions. A mechanism analysis based on the calibrated model provides a behavioral insight into the explanatory power of rational switching behavior of investors on the volatility clustering and long range dependence in return volatility