634 research outputs found
Evidence for Differential Rotation on a T Tauri Star
Five years of photometric monitoring of the T Tauri star HBC 338 in NGC 1333
has revealed that it is a periodic variable, but the period has changed
significantly with time. From 2000-2003, a period near 5.6 days was observed,
while in the last two seasons, the dominant period is near 4.6 days. No other T
Tauri star has been seen to change its period by such a large percentage. We
propose a model in which a differentially rotating star is seen nearly
equator-on and a high latitude spot has gradually been replaced by a low
latitude spot. We show that this model provides an excellent fit to the
observed shapes of the light curves at each epoch. The amplitude and sense of
the inferred differential rotation is similar to what is seen on the Sun. This
may be surprising given the likely high degree of magnetic surface activity on
the star relative to the Sun but we note that HBC 338 is clearly an exceptional
T Tauri star.Comment: Acepted for publication in PAS
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Improving post-partum family planning services provided by female community health volunteers in Nepal: a mixed methods study.
BACKGROUND: Family planning services in the post-partum period, termed post-partum family planning (PPFP) is critical to cover the unmet need for contraception, especially when institutional delivery rates have increased. However, the intention to choose PPFP methods such as post-partum intrauterine devices (PPIUD) remains low in countries such as Nepal. Community health workers such as Female Community Health Volunteers (FCHVs) could play an important role in improving the service coverage of PPFP in Nepal. However, their knowledge of PPFP and community-based services related to PPFP remain unclear. This study aims to assess the effect on community-based PPFP services by improving FCHV's knowledge through orientation on PPFP. METHODS: We conducted this mixed-methods study in Morang District in Nepal. The intervention involved orientation of FCHVs on PPFP methods. We collected quantitative data from three sources; via a survey of FCHVs that assessed their knowledge before and after the intervention, from their monthly reporting forms on counseling coverage of women at different stages of pregnancy from the communities, and by interviewing mothers in their immediate post-partum period in two selected hospitals. We also conducted six focus group discussions with the FCHVs to understand their perception of PPFP and the intervention. We performed descriptive and multivariable analyses for quantitative results and thematic analysis for qualitative data. RESULTS: In total, 230 FCHVs participated in the intervention and their knowledge of PPFP improved significantly after it. The intervention was the only factor significantly associated with their improved knowledge (adjusted odds ratio = 24, P < 0.001) in the multivariable analysis. FCHVs were able to counsel 83.3% of 1872 mothers at different stages of pregnancy in the communities. In the two hospitals, the proportion of mothers in their immediate post-partum period whom reported they were counseled by FCHVs during their pregnancy increased. It improved from 7% before the intervention to 18.1% (P < 0.001) after the intervention. The qualitative findings suggested that the intervention improved their knowledge in providing PPFP counseling. CONCLUSION: The orientation improved the FCHV's knowledge of PPFP and their community-based counseling. Follow-up studies are needed to assess the longer term effect of the FCHV's role in improving community-based PPFP services
Effect of uniaxial strain on the structural and magnetic phase transitions in BaFeAs
We report neutron scattering experiments probing the influence of uniaxial
strain on both the magnetic and structural order parameters in the parent iron
pnictide compound, BaFeAs. Our data show that modest strain fields
along the in-plane orthorhombic b-axis can affect significant changes in phase
behavior simultaneous to the removal of structural twinning effects. As a
result, we demonstrate in BaFeAs samples detwinned via uniaxial strain
that the in-plane C symmetry is broken by \textit{both} the structural
lattice distortion \textit{and} long-range spin ordering at temperatures far
above the nominal (strain-free), phase transition temperatures. Surprising
changes in the magnetic order parameter of this system under relatively small
strain fields also suggest the inherent presence of magnetic domains
fluctuating above the strain-free ordering temperature in this material.Comment: 4 pages, 3 figure
The High-Order-Multiplicity of Unusually Wide M-dwarf Binaries: Eleven New Triple and Quadruple Systems
M-dwarfs in extremely wide binary systems are very rare, and may thus have
different formation processes from those found as single stars or close
binaries in the field. In this paper we search for close companions to a new
sample of 36 extremely wide M-dwarf binaries, covering a spectral type range of
M1 to M5 and a separation range of 600 - 6500 AU. We discover 10 new triple
systems and one new quadruple system. We carefully account for selection
effects including proper motion, magnitude limits, the detection of close
binaries in the SDSS, and other sample biases. The bias-corrected total
high-order-multiple fraction is 45% (+18%/-16%) and the bias-corrected
incidence of quadruple systems is < 5%, both statistically compatible with that
found for the more common close M-dwarf multiple systems. Almost all the
detected companions have similar masses to their primaries, although two very
low mass companions, including a candidate brown dwarf, are found at relatively
large separations. We find that the close-binary separation distribution is
strongly peaked towards < 30AU separations. There is marginally significant
evidence for a change in high-order M-dwarf multiplicity with binding energy
and total mass. We also find 2-sigma evidence of an unexpected increased
high-order-multiple fraction for the widest targets in our survey, with a
high-order-multiple fraction of 21% (+17%/-7%) for systems with separations up
to 2000AU, compared to 77% (+9%/-22%) for systems with separations > 4000AU.
These results suggest that the very widest M-dwarf binary systems need higher
masses to form or to survive.Comment: 11 pages, 14 figures, accepted for publication in Ap
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Prevalence of Postpartum Family Planning Service Coverage in Selected Referral Facilities of Nepal
Introduction: Nepal Society of Obstetricians and Gynecologists jointly with the Nepalese government and with the support from the International Federation of Obstetrics and Gynecology has implemented an initiative to institutionalize postpartum family planning services in selected major referral facilities of Nepal to address the gap of low uptake of postpartum family planning in Nepal. The aim of the study is to find the prevalence of the service coverage of postpartum contraception in the selected facilities.
Methods: A descriptive cross-sectional study was conducted in seven major referral facilities across Nepal. Data were collected from the hospital records of all women who delivered in these facilities between October 2018 and March 2019. Ethical approval for this study was obtained from Nepal Health Research Council. Data analysis was done with SPSS version 23.
Results: Among the 29,072 deliveries from all the facilities, postpartum family planning counseling coverage was 27,301 (93.9%). The prevalence of uptake of Postpartum Intrauterine Device is 1581 (5.4%) and female sterilization is 1830 (6.3%). In total 11387 mothers (52.2%) had the intention to choose a postpartum family planning method. However, 36% of mothers neither used nor had the intention to choose a postpartum family planning method.
Conclusions: The coverage of Postpartum Intrauterine Device counseling service coverage in Nepal is higher in 2018 as compared to 2016-2017 and in other countries implementing Postpartum Intrauterine Device initiatives. However, the prevalence of service coverage of immediate Postpartum Family Planning methods, mainly Postpartum Intrauterine Device in 2018 is lower in Nepal as compared to 2016-2017, and other countries implementing Postpartum Intrauterine Device initiative. More efforts are needed to encourage mothers delivering in the facilities to use the postpartum family planning method
The evolution of antiferromagnetic susceptibility to uniaxial pressure in Ba(Fe{1-x}Co{x})2As2
Neutron diffraction measurements are presented measuring the responses of
both magnetic and structural order parameters of parent and lightly Co-doped
Ba(Fe{1-x}Co{x})2As2 under the application of uniaxial pressure. We find that
the uniaxial pressure induces a thermal shift in the onset of antiferromagnetic
order that grows as a percentage of T_N as Co-doping is increased and the
superconducting phase is approached. Additionally, as uniaxial pressure is
increased within parent and lightly-doped Ba(Fe{1-x}Co{x})2As2 on the first
order side of the tricritical point, we observe a decoupling between the onsets
of the orthorhombic structural distortion and antiferromagnetism. Our findings
place needed constraints on models exploring the nematic susceptibility of the
bilayer pnictides in the tetragonal, paramagnetic regime.Comment: 10 pages, 7 figure
Magnetic order and the electronic ground state in the pyrochlore iridate Nd2Ir2O7
We report a combined muon spin relaxation/rotation, bulk magnetization,
neutron scattering, and transport study of the electronic properties of the
pyrochlore iridate Nd2Ir2O7. We observe the onset of strongly hysteretic
behavior in the temperature dependent magnetization below 120 K, and an abrupt
increase in the temperature dependent resistivity below 8 K. Zero field muon
spin relaxation measurements show that the hysteretic magnetization is driven
by a transition to a magnetically disordered state, and that below 8 K a
complex magnetically ordered ground state sets in, as evidenced by the onset of
heavily damped spontaneous muon precession. Our measurements point toward the
absence of a true metal-to-insulator phase transition in this material and
suggest that Nd2Ir2O7 lies either within or on the metallic side of the
boundary of the Dirac semimetal regime within its topological phase diagram.Comment: 21 pages, 7 figure
Encapsulation of Lactobacillus plantarum in porous maize starch
This study investigated the survival of probiotic Lactobacillus plantarum 299v microencapsulated in native maize starch or partially hydrolyzed maize starches after acid, bile and heat treatments. Scanning electron microscopy and confocal scanning laser microscopy confirmed that naturally present cavities and channels in native maize starch were enlarged by enzymatic hydrolysis allowing them to be filled with probiotics. The formulations using the modified starches had significantly higher initial viable cells compared to native starch after freeze-drying. Compared to free cells, the microencapsulated probiotic bacteria showed a significant improvement in acid tolerance. When comparing unmodified and modified starches, the enzymatic treatments did not significantly improve relative survival, but did result in significantly higher total probiotic numbers after exposure to acid (pH = 2.0, 1 h), bile salt (3% w/v, 4 h) and heat (60 °C, 15min). These results demonstrate that porous maize starch granules allow for a high probiotic loading efficiency and provide enhanced protection to various stressful conditions compared to free cells
Advances of Peripheral Nerve Repair Techniques to Improve Hand Function: A Systematic Review of Literature
Concepts of neuronal damage and repair date back to ancient times. The research in this topic has been growing ever since and numerous nerve repair techniques have evolved throughout the years. Due to our greater understanding of nerve injuries and repair we now distinguish between central and peripheral nervous system. In this review, we have chosen to concentrate on peripheral nerve injuries and in particular those involving the hand. There are no reviews bringing together and summarizing the latest research evidence concerning the most up-to-date techniques used to improve hand function. Therefore, by identifying and evaluating all the published literature in this field, we have summarized all the available information about the advances in peripheral nerve techniques used to improve hand function. The most important ones are the use of resorbable poly[(R)-3-hydroxybutyrate] (PHB), epineural end-to-end suturing, graft repair, nerve transfer, side to side neurorrhaphy and end to side neurorrhaphy between median, radial and ulnar nerves, nerve transplant, nerve repair, external neurolysis and epineural sutures, adjacent neurotization without nerve suturing, Agee endoscopic operation, tourniquet induced anesthesia, toe transfer and meticulous intrinsic repair, free auto nerve grafting, use of distal based neurocutaneous flaps and tubulization. At the same time we found that the patient’s age, tension of repair, time of repair, level of injury and scar formation following surgery affect the prognosis. Despite the thorough findings of this systematic review we suggest that further research in this field is needed
Systematic review on the effects of the physical and social aspects of community pharmacy spaces on service users and staff
AIM: This systematic review aimed to provide new insights into how pharmacy spaces, or the architecture of pharmacies, are experienced by pharmacy service users and staff. The review sought to identify environmental factors which may influence service users' and staff participation in community-based pharmacy health services. METHOD: Ten databases were searched for English language publications, using a combination of search terms relating to pharmacy service users and staff; pharmacy spaces; and health and social care outcomes. Data from the final selected studies were extracted, thematically analysed using a narrative approach and the quality of each study assessed using the Integrated quality Criteria for the Review of Multiple Study designs (ICROMS). RESULTS: 80 articles reporting 80 studies published between 1994 and 2020 were identified; they were from 28 countries, involving around 3234 community pharmacies, 13,615 pharmacy service users, 5056 pharmacists and 78 pharmacy health staff. Most studies (94%) met the ICROMS minimum score, and half did not meet the mandatory quality criteria. Four themes likely to influence service users' and staff experiences of pharmacy health services were identified: (1) privacy; (2) experience of the physical environment; (3) professional image; and (4) risk of error. CONCLUSION: To optimise the delivery and experience of pharmacy health services, these spaces should be made more engaging. Future applied research could focus on optimising inclusive pharmacy design features
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