Neuromyelitis optica MOG-IgG causes reversible lesions in mouse brain.

INTRODUCTION: Antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG) are present in some neuromyelitis optica patients who lack antibodies against aquaporin-4 (AQP4-IgG). The effects of neuromyelitis optica MOG-IgG in the central nervous system have not been investigated in vivo. We microinjected MOG-IgG, obtained from patients with neuromyelitis optica, into mouse brains and compared the results with AQP4-IgG. RESULTS: MOG-IgG caused myelin changes and altered the expression of axonal proteins that are essential for action potential firing, but did not produce inflammation, axonal loss, neuronal or astrocyte death. These changes were independent of complement and recovered within two weeks. By contrast, AQP4-IgG produced complement-mediated myelin loss, neuronal and astrocyte death with limited recovery at two weeks. CONCLUSIONS: These differences mirror the better outcomes for MOG-IgG compared with AQP4-IgG patients and raise the possibility that MOG-IgG contributes to pathology in some neuromyelitis optica patients

Neuromyelitis optica MOG-IgG causes reversible lesions in mouse brain.

INTRODUCTION: Antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG) are present in some neuromyelitis optica patients who lack antibodies against aquaporin-4 (AQP4-IgG). The effects of neuromyelitis optica MOG-IgG in the central nervous system have not been investigated in vivo. We microinjected MOG-IgG, obtained from patients with neuromyelitis optica, into mouse brains and compared the results with AQP4-IgG. RESULTS: MOG-IgG caused myelin changes and altered the expression of axonal proteins that are essential for action potential firing, but did not produce inflammation, axonal loss, neuronal or astrocyte death. These changes were independent of complement and recovered within two weeks. By contrast, AQP4-IgG produced complement-mediated myelin loss, neuronal and astrocyte death with limited recovery at two weeks. CONCLUSIONS: These differences mirror the better outcomes for MOG-IgG compared with AQP4-IgG patients and raise the possibility that MOG-IgG contributes to pathology in some neuromyelitis optica patients

Correlates of loneliness among university students

Background The purpose of this study was to investigate level of loneliness, essential needs during university education, and relationships between loneliness, essential needs, and characteristics of university students. A sample comprising 721 students participated in the study. The mean age was 21.58 (SD = 1.73) with a range from 18 to 25. The majority of the students were female (70.6%) and were living in students' dormitory (67.5%) with low (87.8%) income, away from their parents. Methods The UCLA-R loneliness scale and sociodemographic questionnaire which includes an open-ended question on essential needs during university education were administered. Pearson-Product-Moment correlations were used to explore the relationships between participants' loneliness, needs, and characteristics. Results It was found that 60.2% of the participants experienced loneliness. Economical support (81.6%), social interaction (46.9%) and psychosocial support (35%) were the essential needs during university education reported by the participants. The study findings indicate that there were significant relationships between the needs of economical support, social interaction, and loneliness level of university students. Results also show that there were significant relationships among romantic relationship, parents' status and loneliness. Participants' loneliness levels were relatively higher who had not any romantic relationship and were not from married families. Conclusion The findings of this study provided essential information, about Turkish university students, concerning: level of loneliness and relationships that exist among loneliness, needs and sociodemographic characteristics. The findings also suggest implications for psychosocial practice. Because of the mean of loneliness were found to be high (45.49 ± 10.07), for this study, professionals need to pay attention to Turkish university students' psychosocial state, and need to empower them in establishing social relations

The Interplay Between GUT and Flavour Symmetries in a Pati-Salam x S4 Model

Both Grand Unified symmetries and discrete flavour symmetries are appealing ways to describe apparent structures in the gauge and flavour sectors of the Standard Model. Both symmetries put constraints on the high energy behaviour of the theory. This can give rise to unexpected interplay when building models that possess both symmetries. We investigate on the possibility to combine a Pati-Salam model with the discrete flavour symmetry $S_4$ that gives rise to quark-lepton complementarity. Under appropriate assumptions at the GUT scale, the model reproduces fermion masses and mixings both in the quark and in the lepton sectors. We show that in particular the Higgs sector and the running Yukawa couplings are strongly affected by the combined constraints of the Grand Unified and family symmetries. This in turn reduces the phenomenologically viable parameter space, with high energy mass scales confined to a small region and some parameters in the neutrino sector slightly unnatural. In the allowed regions, we can reproduce the quark masses and the CKM matrix. In the lepton sector, we reproduce the charged lepton masses, including bottom-tau unification and the Georgi-Jarlskog relation as well as the two known angles of the PMNS matrix. The neutrino mass spectrum can present a normal or an inverse hierarchy, and only allowing the neutrino parameters to spread into a range of values between $\lambda^{-2}$ and $\lambda^2$, with $\lambda\simeq0.2$. Finally, our model suggests that the reactor mixing angle is close to its current experimental bound.Comment: 62 pages, 4 figures; references added, version accepted for publication in JHE

Beyond the standard seesaw: neutrino masses from Kahler operators and broken supersymmetry

We investigate supersymmetric scenarios in which neutrino masses are generated by effective d=6 operators in the Kahler potential, rather than by the standard d=5 superpotential operator. First, we discuss some general features of such effective operators, also including SUSY-breaking insertions, and compute the relevant renormalization group equations. Contributions to neutrino masses arise at low energy both at the tree level and through finite threshold corrections. In the second part we present simple explicit realizations in which those Kahler operators arise by integrating out heavy SU(2)_W triplets, as in the type II seesaw. Distinct scenarios emerge, depending on the mechanism and the scale of SUSY-breaking mediation. In particular, we propose an appealing and economical picture in which the heavy seesaw mediators are also messengers of SUSY breaking. In this case, strong correlations exist among neutrino parameters, sparticle and Higgs masses, as well as lepton flavour violating processes. Hence, this scenario can be tested at high-energy colliders, such as the LHC, and at lower energy experiments that measure neutrino parameters or search for rare lepton decays.Comment: LaTeX, 34 pages; some corrections in Section

High rates of burnout among maternal health staff at a referral hospital in Malawi: A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Burnout among maternal healthcare workers in sub-Saharan Africa may have a negative effect on services provided and efforts to mitigate high maternal mortality rates. In Malawi, research on burnout is limited and no empirical research has been conducted specifically among maternal health staff. Therefore, the aims of the study were to examine the prevalence and degree of burnout reported by healthcare workers who provide antenatal, intrapartum, and postnatal services in a district referral hospital in Malawi; and, to explore factors that may influence the level of burnout healthcare workers experience.</p> <p>Methods</p> <p>In the current cross-sectional study, levels of burnout among staff working in obstetrics and gynaecology at a referral hospital in Malawi were examined, in addition to individual and job characteristics that may be associated with burnout.</p> <p>Results</p> <p>In terms of the three dimensions of burnout, of the 101 participants, nearly three quarters (72%) reported emotional exhaustion, over one third (43%) reported depersonalization while almost three quarters (74%) experienced reduced personal accomplishment.</p> <p>Conclusions</p> <p>Based on these findings, burnout appears to be common among participating maternal health staff and they experienced more burnout than their colleagues working in other medical settings and countries. Further research is needed to identify factors specific to Malawi that contribute to burnout in order to inform the development of prevention and treatment within the maternal health setting.</p

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns