A Peer-Led, Social Media-Delivered, Safer Sex Intervention for Chinese College Students: Randomized Controlled Trial

Background: The peer-led, social media-delivered intervention is an emerging method in sexual health promotion. However, no research has yet investigated its effectiveness as compared with other online channels or in an Asian population. Objective: The objective of this study is to compare a peer-led, social media-delivered, safer sex intervention with a sexual health website. Both conditions target Chinese college students in Hong Kong. Methods: A randomized controlled trial was conducted with a peer-led, safer sex Facebook group as the intervention and an existing online sexual health website as the control. The intervention materials were developed with peer input and followed the information-motivation-behavioral skills model; the intervention was moderated by peer educators. The participants filled out the online questionnaires before and after the 6-week intervention period. Outcome evaluations included safer sex attitudes, behavioral skills, and behaviors, while process evaluation focused on online experience, online-visiting frequency, and online engagement. The effect of online-visiting frequency and online engagement on outcome variables was investigated. Results: Of 196 eligible participants—100 in the control group and 96 in the intervention group—who joined the study, 2 (1.0%) control participants joined the Facebook group and 24 of the remaining 194 participants (12.4%) were lost to follow-up. For the process evaluation, participants in the intervention group reported more satisfying online experiences (P<.001) and a higher level of online-visiting frequency (P<.001). They also had more positive comments when compared with the control group. For outcome evaluation, within-group analysis showed significant improvement in condom use attitude (P=.02) and behavioral skills (P<.001) in the intervention group, but not in the control group. No significant between-group difference was found. After adjusting for demographic data, increased online-visiting frequency was associated with better contraceptive use behavioral intention (P=.05), better behavioral skills (P=.02), and more frequent condom use (P=.04). Conclusions: A peer-led, social media-delivered, safer sex intervention was found to be feasible and effective in improving attitudes toward condom use and behavioral skills, but was not significantly more effective than a website. Future research may focus on the long-term effectiveness and cost-effectiveness of this popular method, as well as the potential cultural differences of using social media between different countries.published_or_final_versio

Determination of optimal successor function in phase-based control using neural network

A phase-based method for fixed-time signal control of traffic improves significantly the junction performance over conventional stage-based method of control due to the higher flexibility in specification of signal timings, where the control variables comprise the start and duration of green phases and the cycle time at which the junction is operated. The cycle-structure is specified by a successor function, a combination of 0 and 1 for all incompatible pairs of phases, which indicates the order of phases in a cycle. Normal procedure optimises the timings for each of these successor functions to determine the best timing plan. The computing time is found to be approximately proportional the number of such functions. To reduce the computational requirement, and hence enhance its applicability to real-time actuated control, a neural network is employed in this paper to help identify the optimal successor function for further optimization of timings. Encouraging results are obtained.published_or_final_versio

Dichloro[(1R,2R)-N-(2-pyridylmethylene)-1,2-cyclohexanediamine]copper(II)

The crystal structure of [CuC12(CI2Hi7N3)], containing a five-coordinate Cu n atom with distorted trigonalbipyramidal coordination, is reported. The absolute configuration (1R,2R) has been verified.published_or_final_versio

On LOS Contribution to Ultra-Dense Network

Ultra-dense networks (UDNs) are widely considered as an effective solution to greatly improve coverage by shortening the communication distance between user equipments (UEs) and base stations (BSs). The reality of UDN is that line-of-sight (LOS) communication becomes more likely to occur but this desirable result also complicates the performance analysis of random UDNs and puts an obstacle on the design and optimization of UDNs. The aim of this paper is to derive analytical results that take into account the phenomenon of having mixed LOS and non line-of-sight (NLOS) links in UDNs. In particular, the use of an arbitrary shaped thinning process to model the LOS wireless links allowed us to investigate a wide set of scenarios for what concerns the desired and interfering power levels. Our contribution is an accurate approximation in closed form for the success content delivery probability (SCDP) that decouples the contribution from LOS and NLOS links. Simulation results corroborate the accuracy of the proposed approximation

Concomitant plasmacytoma and B cell lymphoma with discordant light chain expression but clonal identity

Letter to the editorpublished_or_final_versionSpringer Open Choice, 25 May 201

Fault-tolerant parallel scheduling of arbitrary length jobs on a shared channel

We study the problem of scheduling jobs on fault-prone machines communicating via a shared channel, also known as multiple-access channel. We have $n$ arbitrary length jobs to be scheduled on $m$ identical machines, $f$ of which are prone to crashes by an adversary. A machine can inform other machines when a job is completed via the channel without collision detection. Performance is measured by the total number of available machine steps during the whole execution. Our goal is to study the impact of preemption (i.e., interrupting the execution of a job and resuming later in the same or different machine) and failures on the work performance of job processing. The novelty is the ability to identify the features that determine the complexity (difficulty) of the problem. We show that the problem becomes difficult when preemption is not allowed, by showing corresponding lower and upper bounds, the latter with algorithms reaching them. We also prove that randomization helps even more, but only against a non-adaptive adversary; in the presence of more severe adaptive adversary, randomization does not help in any setting. Our work has extended from previous work that focused on settings including: scheduling on multiple-access channel without machine failures, complete information about failures, or incomplete information about failures (like in this work) but with unit length jobs and, hence, without considering preemption

Tamsiniella labiosa gen. et sp. nov., a new freshwater ascomycete from submerged wood

Investigations into the fungi occurring on wood submerged in freshwater ecosystems have revealed a unique, but characteristic group of fungi. In this paper a new pyrenomycete, Tamsiniella labiosa gen. et sp.nov,, is described and illustrated with light, scanning, and transmission electron micrographs. The germs has remarkable short: stipitate cylindrical asei with an internal refractive apical ring that are apically truncate and have an external thickening. Ascospores are ellipsoidal-fusiform and surrounded by a mucilaginous sheath. At the transmission electron microscope level, the annulus iv of the ascus apical apparatus is differentiated from the inner ascus wail layer and is composed of horizontally oriented, eiectron-dense fibrillar material. A narrow plug is present in the centre of the apical ring. An electron-dense amorphous regk oecurs between the outer ascus wall layer and the annulus part of the apical apparatus. The outer ascus wail layer is lacking a the apex. The ultrastructure of the ascus apex differs from those described in the Lasiosphaeriaceae, Sordariaceae, and Xylariaceae.published_or_final_versio

Ultra Dense Edge Caching Networks With Arbitrary User Spatial Density

Cache-enabled small cells can be an effective solution to deliver contents to mobile users with much lower power and latency. While the trend for getting smaller and denser cells is clear, interference will soon become unmanageable and an obstacle when the number of content requests is massive. Moreover, content request is seldom a spatially homogeneous process due to physical impediments (e.g., buidings) and social activities, which makes resource allocation for content delivery more challenging. In this paper, we consider an ultra-dense network (UDN) in which content requests are served by cache-enabled access nodes which can either be active for delivering contents to users, or inactive to reduce interference and network energy consumption. Our aim is to devise an approach that can locally adapt the caching node density and content caching probabilities to accommodate any arbitrary user density and content request for maximizing the network’s successful content delivery probability (SCDP). With a non-homogeneous spatial distribution for user equipments (UEs), we find that user-load, a parameter at the access node, plays a major role in the overall optimization. Simulation results illustrate that the proposed method can obtain superior performance against the considered benchmarks, with up to 150-160% increase, and our optimized solutions effectively adapt to the spatial-dependent user density