Giant cell myocarditis masquerading as orbital myositis with a rapid, fulminant course necessitating mechanical support and heart transplantation.

Giant cell myocarditis (GCM), a rapidly progressive inflammation of the myocardium, is associated with fulminant heart failure, refractory ventricular arrhythmias, and conduction system abnormalities. Few case reports have noted orbital myositis as the initial clinical presentation. Our case demonstrates a unique presentation of GCM with only ocular symptoms, which unlike prior studies, rapidly progressed to heart failure, tachyarrhythmias, and conduction disease. Our case necessitated quick recognition and treatment with mechanical support making this the first known case of GCM with successful placement of biventricular assist devices and ultimately with heart transplantation

Resistance on the Internet: A study of the Singapore Case

Master'sMASTER OF SOCIAL SCIENCE

A Multidisciplinary Investigation to Determine the Structure and Source of Dimeric Impurities in AMG 517 Drug Substance

In the initial scale-up batches of the experimental drug substance AMG 517, a pair of unexpected impurities was observed by HPLC. Analysis of data from initial LC-MS experiments indicated the presence of two dimer-like molecules. One impurity had an additional sulfur atom incorporated into its structure relative to the other impurity. Isolation of the impurities was performed, and further structural elucidation experiments were conducted with high-resolution LC-MS and 2D NMR. The dimeric structures were confirmed, with one of the impurities having an unexpected C-S-C linkage. Based on the synthetic route of AMG 517, it was unlikely that these impurities were generated during the last two steps of the process. Stress studies on the enriched impurities were carried out to further confirm the existence of the C-S-C linkage in the benzothiazole portion of AMG 517. Further investigation revealed that these two dimeric impurities originated from existing impurities in the AMG 517 starting material, N-acetyl benzothiazole. The characterization of these two dimeric impurities allowed for better quality control of new batches of the N-acetyl benzothiazole starting material. As a result, subsequent batches of AMG 517 contained no reportable levels of these two impuritie

Gift Contagion in Online Groups: Evidence From WeChat Red Packets

Gifts are important instruments for forming bonds in interpersonal relationships. Our study analyzes the phenomenon of gift contagion in online groups. Gift contagion encourages social bonds of prompting further gifts; it may also promote group interaction and solidarity. Using data on 36 million online red packet gifts on China's social site WeChat, we leverage a natural experimental design to identify the social contagion of gift giving in online groups. Our natural experiment is enabled by the randomization of the gift amount allocation algorithm on WeChat, which addresses the common challenge of causal identifications in observational data. Our study provides evidence of gift contagion: on average, receiving one additional dollar causes a recipient to send 18 cents back to the group within the subsequent 24 hours. Decomposing this effect, we find that it is mainly driven by the extensive margin -- more recipients are triggered to send red packets. Moreover, we find that this effect is stronger for "luckiest draw" recipients, suggesting the presence of a group norm regarding the next red packet sender. Finally, we investigate the moderating effects of group- and individual-level social network characteristics on gift contagion as well as the causal impact of receiving gifts on group network structure. Our study has implications for promoting group dynamics and designing marketing strategies for product adoption.Comment: 33 page

Polaron-ion correlations in Li_xFePO_4 studied by x-ray nuclear resonant forward scattering at elevated pressure and temperature

Valence fluctuations of Fe^(2+) and Fe^(3+) were studied in a solid solution of Li_xFePO_4 by nuclear resonant forward scattering of synchrotron x rays while the sample was heated in a diamond-anvil pressure cell. The spectra acquired at different temperatures and pressures were analyzed for the frequencies of valence changes using the Blume-Tjon model of a system with a fluctuating Hamiltonian. These frequencies were analyzed to obtain activation enthalpies and an activation volume for polaron hopping. There was a large suppression of hopping frequency with pressure, giving an activation volume for polaron hopping of 5.8±0.7 Å^ 3. This large, positive value is typical of ion diffusion, which indicates correlated motions of polarons and Li^+ ions that alter the dynamics of both. Monte Carlo simulations were used to estimate the strength of the polaron-ion interaction energy

Expressing the human proteome for affinity proteomics: optimising expression of soluble protein domains and in vivo biotinylation

The generation of affinity reagents to large numbers of human proteins depends on the ability to express the target proteins as high-quality antigens. The Structural Genomics Consortium (SGC) focuses on the production and structure determination of human proteins. In a 7-year period, the SGC has deposited crystal structures of >800 human protein domains, and has additionally expressed and purified a similar number of protein domains that have not yet been crystallised. The targets include a diversity of protein domains, with an attempt to provide high coverage of protein families. The family approach provides an excellent basis for characterising the selectivity of affinity reagents. We present a summary of the approaches used to generate purified human proteins or protein domains, a test case demonstrating the ability to rapidly generate new proteins, and an optimisation study on the modification of >70 proteins by biotinylation in vivo. These results provide a unique synergy between large-scale structural projects and the recent efforts to produce a wide coverage of affinity reagents to the human proteome

Cross-sector, sessional employment of pharmacists in rural hospitals in Australia and New Zealand: a qualitative study exploring pharmacists’ perceptions and experiences

Background: Many rural hospitals in Australia and New Zealand do not have an on-site pharmacist. Sessional employment of a local pharmacist offers a potential solution to address the clinical service needs of non-pharmacist rural hospitals. This study explored sessional service models involving pharmacists and factors (enablers and challenges) impacting on these models, with a view to informing future sessional employment. Methods: A series of semi-structured one-on-one interviews was conducted with rural pharmacists with experience, or intention to practise, in a sessional employment role in Australia and New Zealand. Participants were identified via relevant newsletters, discussion forums and referrals from contacts. Interviews were conducted during August 2012-January 2013 via telephone or Skype™, for approximately 40–55 minutes each, and recorded.Results: Seventeen pharmacists were interviewed: eight with ongoing sessional roles, five with sessional experience, and four working towards sessional employment. Most participants provided sessional hospital services on a weekly basis, mainly focusing on inpatient medication review and consultation. Recognition of the value of pharmacists’ involvement and engagement with other healthcare providers facilitated establishment and continuity of sessional services. Funds pooled from various sources supplemented some pharmacists’ remuneration in the absence of designated government funding. Enhanced employment opportunities, district support and flexibility in services facilitated the continuous operation of the sessional service. Conclusions: There is potential to address clinical pharmacy service needs in rural hospitals by cross-sector employment of pharmacists. The reported sessional model arrangements, factors impacting on sessional employment of pharmacists and learnings shared by the participants should assist development of similar models in other rural communities

Microtubules gate tau condensation to spatially regulate microtubule functions.

Tau is an abundant microtubule-associated protein in neurons. Tau aggregation into insoluble fibrils is a hallmark of Alzheimer's disease and other types of dementia1, yet the physiological state of tau molecules within cells remains unclear. Using single-molecule imaging, we directly observe that the microtubule lattice regulates reversible tau self-association, leading to localized, dynamic condensation of tau molecules on the microtubule surface. Tau condensates form selectively permissible barriers, spatially regulating the activity of microtubule-severing enzymes and the movement of molecular motors through their boundaries. We propose that reversible self-association of tau molecules, gated by the microtubule lattice, is an important mechanism of the biological functions of tau, and that oligomerization of tau is a common property shared between the physiological and disease-associated forms of the molecule

Challenges and opportunities for quantifying roots and rhizosphere interactions through imaging and image analysis

The morphology of roots and root systems influences the efficiency by which plants acquire nutrients and water, anchor themselves and provide stability to the surrounding soil. Plant genotype and the biotic and abiotic environment significantly influence root morphology, growth and ultimately crop yield. The challenge for researchers interested in phenotyping root systems is, therefore, not just to measure roots and link their phenotype to the plant genotype, but also to understand how the growth of roots is influenced by their environment. This review discusses progress in quantifying root system parameters (e.g. in terms of size, shape and dynamics) using imaging and image analysis technologies and also discusses their potential for providing a better understanding of root:soil interactions. Significant progress has been made in image acquisition techniques, however trade-offs exist between sample throughput, sample size, image resolution and information gained. All of these factors impact on downstream image analysis processes. While there have been significant advances in computation power, limitations still exist in statistical processes involved in image analysis. Utilizing and combining different imaging systems, integrating measurements and image analysis where possible, and amalgamating data will allow researchers to gain a better understanding of root:soil interactions