The best of both worlds? Online ties and the alternating use of social network sites in the context of migration

While an ever-growing body of research is concerned with user behavior on individual social network sites (SNSs)—mostly Facebook—studies addressing an alternating use of two or more SNS are rare. Here, we investigate the relationship between alternating SNS use and social capital in the context of migration. Alternating SNS use avoids some of the problems associated with large networks located on one site; in particular the management of different social or cultural spheres. Not only does this strategy hold potential for increased social capital, it also provides a particular incentive for migrants faced with the challenge of staying in touch with back home and managing a new social environment. Two survey studies are presented that focus on the relationship between alternating SNS use and online ties in a migrant context involving Indian nationals. Study 1 looked at migration within India, whereas Study 2 compared international with domestic SNS users. In both studies, alternating SNS use added to the prediction of online network size and accounted for differences in network size found for migrant and non-migrant users. Differences were due to the number of peripheral ties, rather than core ties. Findings suggest that alternating SNS use may constitute a compensatory strategy that helps to overcome lower levels of socializing represented through a single SNS

Activity in social media and intimacy in social relationships

We investigated associations between online and offline socialising and groups of social ties as postulated by the Social Brain Hypothesis (SBH). An online survey of social media use, social satisfaction and loneliness generated 249 complete responses from a sample of staff and students at the University of Manchester. Regression-based analyses showed that offline social activities and social time were positively associated with size of a core support group and social satisfaction. In contrast, social media time was positively associated with social satisfaction and the size of the total network, while the number of online contacts was positively related to social satisfaction, size of a wider sympathy group and total network size. No effect for loneliness was found. The number of ties reported for each SBH group was similar to that in previous studies. The more intimate support group (∼5) appears to be more closely connected with offline social activities, whereas social media use and contacts influence the less intimate sympathy group (∼15) and total network (∼150). These findings provide further support for functional differences between different layers of closeness in personal networks, and they help us in further defining the boundaries of relationship enhancement via communication technology

Management of Acute Particulate Fouling in a Titanium Dioxide Reactor System

The gas-phase manufacture of titanium dioxide is subject to acute fouling in the cooler unit located directly downstream of the reactor which quenches the reaction. A model of the cooler system was constructed, incorporating aspects of compressible flow, multimode heat transfer, fouling, and changes in geometry. This indicated that deposition could be very rapid. The effect of deposit layer buildup required measurement of the thermal conductivity of the porous layer; this was achieved using a novel testing device similar to that reported by Tan et al. (2006), for measuring the thermal conductivity of surface coatings. Active mitigation techniques are employed to reduce the effect of rapid fouling. The effectiveness of adding an erodent, in this case sand, to the flow was appraised by studying the breakup of deposit layers by impinging particles. The experimental conditions (high-temperature chlorine gas, high flow velocities) were simulated in cold experiments by matching the inertia and size of test particles to those of the sand. These studies showed that sand at the feed size would detach deposits, but could result in breakage of the sand particles. Mitigation efficiency is then determined by sand distribution and redistribution.Funding for VYL from Huntsman is gratefully acknowledged

Requirements modelling and formal analysis using graph operations

The increasing complexity of enterprise systems requires a more advanced analysis of the representation of services expected than is currently possible. Consequently, the specification stage, which could be facilitated by formal verification, becomes very important to the system life-cycle. This paper presents a formal modelling approach, which may be used in order to better represent the reality of the system and to verify the awaited or existing system’s properties, taking into account the environmental characteristics. For that, we firstly propose a formalization process based upon properties specification, and secondly we use Conceptual Graphs operations to develop reasoning mechanisms of verifying requirements statements. The graphic visualization of these reasoning enables us to correctly capture the system specifications by making it easier to determine if desired properties hold. It is applied to the field of Enterprise modelling

Cardiac tamponade and paroxysmal third-degree atrioventricular block revealing a primary cardiac non-Hodgkin large B-cell lymphoma of the right ventricle: a case report

<p>Abstract</p> <p>Introduction</p> <p>Primary cardiac lymphoma is rare.</p> <p>Case Presentation</p> <p>We report the case of a 64-year-old non-immunodeficient Caucasian man, with cardiac tamponade and paroxysmal third-degree atrioventricular block. Echocardiography revealed the presence of a large pericardial effusion with signs of tamponade and a right ventricular mass was suspected. Scanner investigations clarified the sites, extension and anatomic details of myocardial and pericardial infiltration. Surgical resection was performed due to the rapid impairment of his cardiac function. Analysis of the pericardial fluid and histology confirmed the diagnosis of non-Hodgkin large B-cell lymphoma. He was treated with chemotherapy.</p> <p>Conclusion</p> <p>The prognosis remains poor for this type of tumor due to delays in diagnosis and the importance of the site of disease.</p

The selectivity, voltage-dependence and acid sensitivity of the tandem pore potassium channel TASK-1 : contributions of the pore domains

We have investigated the contribution to ionic selectivity of residues in the selectivity filter and pore helices of the P1 and P2 domains in the acid sensitive potassium channel TASK-1. We used site directed mutagenesis and electrophysiological studies, assisted by structural models built through computational methods. We have measured selectivity in channels expressed in Xenopus oocytes, using voltage clamp to measure shifts in reversal potential and current amplitudes when Rb+ or Na+ replaced extracellular K+. Both P1 and P2 contribute to selectivity, and most mutations, including mutation of residues in the triplets GYG and GFG in P1 and P2, made channels nonselective. We interpret the effects of these—and of other mutations—in terms of the way the pore is likely to be stabilised structurally. We show also that residues in the outer pore mouth contribute to selectivity in TASK-1. Mutations resulting in loss of selectivity (e.g. I94S, G95A) were associated with slowing of the response of channels to depolarisation. More important physiologically, pH sensitivity is also lost or altered by such mutations. Mutations that retained selectivity (e.g. I94L, I94V) also retained their response to acidification. It is likely that responses both to voltage and pH changes involve gating at the selectivity filter

Accumulation of Self-Reactive Naive and Memory B Cell Reveals Sequential Defects in B Cell Tolerance Checkpoints in Sjogren's Syndrome

This work was funded by grants number 18237 and 20089 from Arthritis Research UK (http://www.arthritisresearchuk.org) to MB and the William Harvey Research Foundation. EC was recipient of short-term travel fellowships from EMBO (ASTF 318-2010) and EFIS-IL

An enhanced partial order curve comparison algorithm and its application to analyzing protein folding trajectories

<p>Abstract</p> <p>Background</p> <p>Understanding how proteins fold is essential to our quest in discovering how life works at the molecular level. Current computation power enables researchers to produce a huge amount of folding simulation data. Hence there is a pressing need to be able to interpret and identify novel folding features from them.</p> <p>Results</p> <p>In this paper, we model each folding trajectory as a multi-dimensional curve. We then develop an effective multiple curve comparison (MCC) algorithm, called the <it>enhanced partial order (EPO) </it>algorithm, to extract features from a set of diverse folding trajectories, including both successful and unsuccessful simulation runs. The EPO algorithm addresses several new challenges presented by comparing high dimensional curves coming from folding trajectories. A detailed case study on miniprotein Trp-cage <abbrgrp><abbr bid="B1">1</abbr></abbrgrp> demonstrates that our algorithm can detect similarities at rather low level, and extract biologically meaningful folding events.</p> <p>Conclusion</p> <p>The EPO algorithm is general and applicable to a wide range of applications. We demonstrate its generality and effectiveness by applying it to aligning multiple protein structures with low similarities. For user's convenience, we provide a web server for the algorithm at <url>http://db.cse.ohio-state.edu/EPO</url>.</p

Regrets Associated with Providing Healthcare: Qualitative Study of Experiences of Hospital-Based Physicians and Nurses

Regret is an unavoidable corollary of clinical practice. Physicians and nurses perform countless clinical decisions and actions, in a context characterised by time pressure, information overload, complexity and uncertainty

Antennal sensilla of two female anopheline sibling species with differing host ranges

BACKGROUND: Volatile odors are important sensory inputs that shape the behaviour of insects, including agricultural pests and disease vectors. Anopheles gambiae s.s. is a highly anthropophilic mosquito and is the major vector for human malaria in sub-Sahara Africa, while Anopheles quadriannulatus, largely due to its zoophilic behaviour, is considered a non-vector species in the same region. Careful studies of olfaction in these sibling species may lead to insights about the mechanisms that drive host preference behaviour. In the present study, the external anatomy of the antenna, the principle olfactory organ in the female mosquito of both species, was examined as an initial step toward more detailed comparisons. METHODS: Scanning electron and light microscopy were used to examine the antennae ultrastructures of adult female An. gambiae s.s. and An. quadriannulatus. Sensory structures, called sensilla, were categorized and counted; their distributions are reported here as well as densities calculated for each species. RESULTS: Both An. gambiae s.s. and An. quadriannulatus bear five classes of sensilla on their antennae: chaetica (bristles), trichodea (hairs), basiconica (pegs), coeloconica (pitted pegs), and ampullacea (pegs in tubes). Female An. quadriannulatus antennae have approximately one-third more sensilla, and a proportionally larger surface area, than female An. gambiae s.s. antennae. CONCLUSION: The same types of sensilla are found on the antennae of both species. While An. quadriannulatus has greater numbers of each sensilla type, sensilla densities are very similar for each species, suggesting that other factors may be more important to such olfactory-driven behaviours as host preference