442 research outputs found
Can we identify women who initiate and then prematurely cease breastfeeding? An Australian multicentre cohort study
Background: Health authorities recommend 6 months of fully breastfeeding and continuation of breastfeeding for at least a year. Many women initiate breastfeeding in hospital but discontinue before the six-month period, and therefore do not optimise the public health benefits. The aim of this study was to determine whether these women could be identified at hospital discharge, to enable targeted interventions.
Methods: A secondary analysis of women who intended to breastfeed and were enrolled in a large randomized trial was undertaken. Women were enrolled in the antenatal period and antenatal, delivery and six month postnatal questionnaires were completed. Univariate and multivariate analyses were undertaken to determine the variables associated with early cessation of breastfeeding within six months, compared to women who continued to breastfeed.
Results: Of 2148 women who initiated breastfeeding in hospital, 877 continued to breastfed either partially (N = 262) or fully (N = 615) until six months postpartum and 1271 ceased breastfeeding early. Median breastfeeding duration in women who ceased early was 3+6 weeks (IQR 1+1 to 11+2 weeks). In multivariate analysis, factors that were significantly associated with early cessation of breastfeeding were maternal factors of lower education (less than 12 years of schooling, no completion of further education), smoking (pre-pregnancy or during pregnancy), and newborn factors of preterm birth and low birthweight (all p \u3c 0.01). These variables correctly identify 83% of women.
Conclusion: We can identify women who initiate and then prematurely discontinue breastfeeding prior to hospital discharge. Evaluation of additional interventions to support longer duration of breastfeeding in women at risk of ceasing prematurely is needed
Oxidation of Methanol on 2nd and 3rd Row Group VIII Transition Metals (Pt, Ir, Os, Pd, Rh, and Ru): Application to Direct Methanol Fuel Cells
Using first principles quantum mechanics [nonlocal density functional theory (B3LYP)], we calculated the 13 most likely intermediate species for methanol oxidation on clusters of all 2nd and 3rd row Group VIII transition metals for all three likely binding sites (top, bridge, and cap). This comprehensive set of binding energies and structures allows a detailed analysis of possible reaction mechanisms and how they change for different metals. This illustrates the role in which modern quantum chemical methods can be used to provide data for combinatorial strategies for discovering and designing new catalysts. We find that methanol dehydrogenation is most facile on Pt, with the hydrogens preferentially stripped off the carbon end. However, water dehydrogenation is most facile on Ru. These results support the bifunctional mechanism for methanol oxidation on Pt−Ru alloys in direct methanol fuel cells (DMFCs). We find that pure Os is capable of performing both functionalities without cocatalyst. We suggest that pure Os be examined as a potential catalyst for low overpotential, highly dispersed catalyst DMFCs. Pathways to form the second C−O bond differ between the pure metals (Pt and Os) in which (CO)_(ads) is probably activated by (OH)_(ads) and the Pt−Ru binary system in which (COH)_(ads) is probably activated by O_(ads). For all cases we find that formation of (COOH)_(ads) is an important precursor to the final dehydrogenation to desorb CO_2 from the surface
Next-to-Leading order approximation of polarized valon and parton distributions
Polarized parton distributions and structure functions of the nucleon are
analyzed in the improved valon model. The valon representation provides a model
to represent hadrons in terms of quarks, providing a unified description of
bound state and scattering properties of hadrons. Polarized valon distributions
are seen to play an important role in describing the spin dependence of parton
distributions in the leading order (LO) and next-to-leading order (NLO)
approximations. In the polarized case, a convolution integral is derived in the
framework of the valon model. The Polarized valon distribution in a proton and
the polarized parton distributions inside the valon are necessary to obtain the
polarized parton distributions in a proton. Bernstein polynomial averages are
used to extract the unknown parameters of the polarized valon distributions by
fitting to the available experimental data. The predictions for the NLO
calculations of the polarized parton distributions and proton structure
functions are compared with the LO approximation. It is shown that the results
of the calculations for the proton structure function, , and its first
moment, , are in good agreement with the experimental data for a
range of values of . Finally the spin contribution of the valons to the
proton is calculated.Comment: 22 pages, 7 figures. Published in Journal of High Energy Physics
(JHEP
Inflammatory complications of CGRP monoclonal antibodies: a case series
BACKGROUND:
Calcitonin gene-related peptide (CGRP) is expressed throughout the body and is a known mediator of migraine, exerting this biological effect through activation of trigeminovascular, meningeal and associated neuronal pathways located in close proximity to the central nervous system. Monoclonal antibodies (mAb) targeting the CGRP pathway are an effective new preventive treatment for migraine, with a generally favourable adverse event profile. Pre-clinical evidence supports an anti-inflammatory/immunoregulatory role for CGRP in other organ systems, and therefore inhibition of the normal action of this peptide may promote a pro-inflammatory response.
CASES:
We present a case series of eight patients with new or significantly worsened inflammatory pathology in close temporal association with the commencement of CGRP mAb therapy.
CONCLUSION:
This case series provides novel insights on the potential molecular mechanisms and side-effects of CGRP antagonism in migraine and supports clinical vigilance in patient care going forward
Current status of acute hepatopancreatic necrosis disease (AHPND) of farmed shrimp in Malaysia
A report about a disease problem in cultured whiteleg shrimp (Penaeus vannamei) was first received by the National Fish Health Research Center (NaFisH) in 2011 from Perak State showing signs of white feces and slow death leading to serious mortality rate. Later, in September of the same year, the Malaysian Shrimp Farmers Association (MSFA) reported to Department of Fisheries (DOF) severe mortalities in almost all of the whiteleg shrimp farms throughout Peninsular Malaysia. Sampling of shrimps for disease diagnosis was then conducted by NaFisH. The bacteriological and histopathological examinations revealed respectively the isolation of V. parahemolyticus and massive sloughing of hepatopancreatic epithelial cells. The disease was subsequently identified as acute hepatopancreatic necrosis disease (AHPND). From our 3-year study, the annual prevalence rates of AHPND were 50%, 26% and 73% in 2011, 2012 and 2013, respectively. At present, AHPND still persists in Malaysia but at a lower prevalence. The risk factors associated with the disease were studied, however, varied environmental and management data analyzed were inconclusive to relate any one parameter directly to the disease. To help ensure the early detection of AHPND, an experimental observation study on `gut scorecard was carried out and this was confirmed by PCR and histopathology. Validation of this technique has yet to be carried out to ensure its reliability. We also examined the potential use of some commercial products such as probiotics and disinfectants available in the market but unfortunately results showed that they were not effective in controlling AHPND. Control measures applied by the farmers such as the use of probiotics were also verified but data generated likewise appeared to be inconclusive. On the contrary, our preliminary study on the antibacterial property of the plant extracts, i.e. betel and lemongrass, incorporated in the feed showed some prophylactic and chemotherapeutic potential against AHPND. However, comprehensive in vitro and in vivo trials are still currently being undertaken to elucidate its efficacy and practical applications. To ensure the shrimp industry s sustainability in Malaysia, results of our ongoing and future studies aimed at preventing and controlling unwarranted outbreaks of AHPND and other emerging transboundary diseases of penaeid shrimps will be continually disseminated to shrimp farmers and pertinent stakeholders
Next-to-Leading Order Constituent Quark Structure and Hadronic Structure Functions
We calculate the partonic structure of a constituent quark in the
Next-to-Leading Order framework. The structure of any hadron can be obtained
thereafter using a convolution method. Such a procedure is used to generate the
structure function of proton and pion in NLO, neglecting certain corrections to
. It is shown that while the constituent quark structure is
generated purely perturbatively and accounts for the most part of the hadronic
structure, there is a few percent contributions coming from the nonperturbative
sector in the hadronic structure. This contribution plays the key role in
explaining the SU(2) symmetry breaking of the nucleon sea and the observed
violation of Gottfried sum rule. These effects are calculated. We obtained an
Excellent agreement with the experimental data in a wide range of and for the proton structure function. We
have also calculated Pion structure and compared it with the existing data.
Again, the model calculations agree rather well with the data from experiment.Comment: 32 pages,10 figures, Accepted to publish in Phys. Rev.
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