4,677 research outputs found
Large theta_13 from a model with broken L_e-L_mu-L_tau symmetry
Recent data in the neutrino sector point towards a relatively large value of
the reactor angle, incompatible with a vanishing theta_ 13 at about 3 sigma. In
order to explain such a result, we propose a SUSY model based on the broken
L_e-L_mu-L_tau symmetry, where large deviations from the symmetric limit
theta_12 = pi/4, tan(theta_23) \sim O(1) and theta_13 = 0 mainly come from the
charged lepton sector. We show that a description of all neutrino data is
possible if the charged lepton mass matrix has a special pattern of complex
matrix elements.Comment: 9 pages, 2 figures. v2: comments and references added, as published
in JHE
A realistic pattern of fermion masses from a five-dimensional SO(10) model
We provide a unified description of fermion masses and mixing angles in the
framework of a supersymmetric grand unified SO(10) model with anarchic Yukawa
couplings of order unity. The space-time is five dimensional and the extra flat
spatial dimension is compactified on the orbifold ,
leading to Pati-Salam gauge symmetry on the boundary where Yukawa interactions
are localised. The gauge symmetry breaking is completed by means of a rather
economic scalar sector, avoiding the doublet-triplet splitting problem. The
matter fields live in the bulk and their massless modes get exponential
profiles, which naturally explain the mass hierarchy of the different fermion
generations. Quarks and leptons properties are naturally reproduced by a
mechanism, first proposed by Kitano and Li, that lifts the SO(10) degeneracy of
bulk masses in terms of a single parameter. The model provides a realistic
pattern of fermion masses and mixing angles for large values of . It
favours normally ordered neutrino mass spectrum with the lightest neutrino mass
below 0.01 eV and no preference for leptonic CP violating phases. The right
handed neutrino mass spectrum is very hierarchical and does not allow for
thermal leptogenesis. We analyse several variants of the basic framework and
find that the results concerning the fermion spectrum are remarkably stable.Comment: 30 pages, 7 figures, 4 table
The Healthy Activity Program lay counsellor delivered treatment for severe depression in India: systematic development and randomised evaluation
BACKGROUND: Reducing the global treatment gap for mental disorders requires treatments that are economical, effective and culturally appropriate. AIMS: To describe a systematic approach to the development of a brief psychological treatment for patients with severe depression delivered by lay counsellors in primary healthcare. METHOD: The treatment was developed in three stages using a variety of methods: (a) identifying potential strategies; (b) developing a theoretical framework; and (c) evaluating the acceptability, feasibility and effectiveness of the psychological treatment. RESULTS: The Healthy Activity Program (HAP) is delivered over 6-8 sessions and consists of behavioral activation as the core psychological framework with added emphasis on strategies such as problem-solving and activation of social networks. Key elements to improve acceptability and feasibility are also included. In an intention-to-treat analysis of a pilot randomised controlled trial (55 participants), the prevalence of depression (Beck Depression Inventory II ⩾19) after 2 months was lower in the HAP than the control arm (adjusted risk ratio = 0.55, 95% CI 0.32-0.94,P= 0.01). CONCLUSIONS: Our systematic approach to the development of psychological treatments could be extended to other mental disorders. HAP is an acceptable and effective brief psychological treatment for severe depression delivered by lay counsellors in primary care
Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial
Background
Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications. The aim of this large randomised controlled trial was to collect data to enhance the validity and applicability of the evidence from previous trials to inform practice.
Methods
In this randomised placebo-controlled trial, we recruited very preterm infants born before 32 weeks' gestation in 37 UK hospitals and younger than 72 h at randomisation. Exclusion criteria were presence of a severe congenital anomaly, anticipated enteral fasting for longer than 14 days, or no realistic prospect of survival. Eligible infants were randomly assigned (1:1) to receive either enteral bovine lactoferrin (150 mg/kg per day; maximum 300 mg/day; lactoferrin group) or sucrose (same dose; control group) once daily until 34 weeks' postmenstrual age. Web-based randomisation minimised for recruitment site, gestation (completed weeks), sex, and single versus multifetal pregnancy. Parents, caregivers, and outcome assessors were unaware of group assignment. The primary outcome was microbiologically confirmed or clinically suspected late-onset infection (occurring >72 h after birth), which was assessed in all participants for whom primary outcome data was available by calculating the relative risk ratio with 95% CI between the two groups. The trial is registered with the International Standard Randomised Controlled Trial Number 88261002.
Findings
We recruited 2203 participants between May 7, 2014, and Sept 28, 2017, of whom 1099 were assigned to the lactoferrin group and 1104 to the control group. Four infants had consent withdrawn or unconfirmed, leaving 1098 infants in the lactoferrin group and 1101 in the sucrose group. Primary outcome data for 2182 infants (1093 [99·5%] of 1098 in the lactoferrin group and 1089 [99·0] of 1101 in the control group) were available for inclusion in the modified intention-to-treat analyses. 316 (29%) of 1093 infants in the intervention group acquired a late-onset infection versus 334 (31%) of 1089 in the control group. The risk ratio adjusted for minimisation factors was 0·95 (95% CI 0·86–1·04; p=0·233). During the trial there were 16 serious adverse events for infants in the lactoferrin group and 10 for infants in the control group. Two events in the lactoferrin group (one case of blood in stool and one death after intestinal perforation) were assessed as being possibly related to the trial intervention.
Interpretation
Enteral supplementation with bovine lactoferrin does not reduce the risk of late-onset infection in very preterm infants. These data do not support its routine use to prevent late-onset infection and associated morbidity or mortality in very preterm infants.
Funding
UK National Institute for Health Research Health Technology Assessment programme (10/57/49)
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Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial
Background
Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications. The aim of this large randomised controlled trial was to collect data to enhance the validity and applicability of the evidence from previous trials to inform practice.
Methods
In this randomised placebo-controlled trial, we recruited very preterm infants born before 32 weeks' gestation in 37 UK hospitals and younger than 72 h at randomisation. Exclusion criteria were presence of a severe congenital anomaly, anticipated enteral fasting for longer than 14 days, or no realistic prospect of survival. Eligible infants were randomly assigned (1:1) to receive either enteral bovine lactoferrin (150 mg/kg per day; maximum 300 mg/day; lactoferrin group) or sucrose (same dose; control group) once daily until 34 weeks' postmenstrual age. Web-based randomisation minimised for recruitment site, gestation (completed weeks), sex, and single versus multifetal pregnancy. Parents, caregivers, and outcome assessors were unaware of group assignment. The primary outcome was microbiologically confirmed or clinically suspected late-onset infection (occurring >72 h after birth), which was assessed in all participants for whom primary outcome data was available by calculating the relative risk ratio with 95% CI between the two groups. The trial is registered with the International Standard Randomised Controlled Trial Number 88261002.
Findings
We recruited 2203 participants between May 7, 2014, and Sept 28, 2017, of whom 1099 were assigned to the lactoferrin group and 1104 to the control group. Four infants had consent withdrawn or unconfirmed, leaving 1098 infants in the lactoferrin group and 1101 in the sucrose group. Primary outcome data for 2182 infants (1093 [99·5%] of 1098 in the lactoferrin group and 1089 [99·0] of 1101 in the control group) were available for inclusion in the modified intention-to-treat analyses. 316 (29%) of 1093 infants in the intervention group acquired a late-onset infection versus 334 (31%) of 1089 in the control group. The risk ratio adjusted for minimisation factors was 0·95 (95% CI 0·86–1·04; p=0·233). During the trial there were 16 serious adverse events for infants in the lactoferrin group and 10 for infants in the control group. Two events in the lactoferrin group (one case of blood in stool and one death after intestinal perforation) were assessed as being possibly related to the trial intervention.
Interpretation
Enteral supplementation with bovine lactoferrin does not reduce the risk of late-onset infection in very preterm infants. These data do not support its routine use to prevent late-onset infection and associated morbidity or mortality in very preterm infants.
Funding
UK National Institute for Health Research Health Technology Assessment programme (10/57/49)
First search for gravitational waves from the youngest known neutron star
We present a search for periodic gravitational waves from the neutron star in the supernova remnant Cassiopeia
A. The search coherently analyzes data in a 12 day interval taken from the fifth science run of the Laser
Interferometer Gravitational-Wave Observatory. It searches gravitational-wave frequencies from 100 to 300 Hz
and covers a wide range of first and second frequency derivatives appropriate for the age of the remnant and
for different spin-down mechanisms. No gravitational-wave signal was detected. Within the range of search
frequencies, we set 95% confidence upper limits of (0.7–1.2) × 10^(−24) on the intrinsic gravitational-wave
strain, (0.4–4) × 10^(−4) on the equatorial ellipticity of the neutron star, and 0.005–0.14 on the amplitude of
r-mode oscillations of the neutron star. These direct upper limits beat indirect limits derived from energy
conservation and enter the range of theoretical predictions involving crystalline exotic matter or runaway r-modes.
This paper is also the first gravitational-wave search to present upper limits on the r-mode amplitude
Search for Gravitational-wave Inspiral Signals Associated with Short Gamma-ray Bursts During LIGO's Fifth and Virgo's First Science Run
Progenitor scenarios for short gamma-ray bursts (short GRBs) include coalescenses of two neutron stars or a neutron star and black hole, which would necessarily be accompanied by the emission of strong gravitational waves. We present a search for these known gravitational-wave signatures in temporal and directional coincidence with 22 GRBs that had sufficient gravitational-wave data available in multiple instruments during LIGO's fifth science run, S5, and Virgo's first science run, VSR1. We find no statistically significant gravitational-wave candidates within a [ – 5, + 1) s window around the trigger time of any GRB. Using the Wilcoxon-Mann-Whitney U-test, we find no evidence for an excess of weak gravitational-wave signals in our sample of GRBs. We exclude neutron star-black hole progenitors to a median 90% confidence exclusion distance of 6.7 Mpc
The Role of Health Systems Factors in Facilitating Access to Psychotropic Medicines: A Cross-Sectional Analysis of the WHO-AIMS in 63 Low- and Middle-Income Countries
In a cross-sectional analysis of WHO-AIMS data, Ryan McBain and colleagues investigate the associations between health system components and access to psychotropic drugs in 63 low and middle income countries
Structural Integration in Language and Music: Evidence for a Shared System.
In this study, we investigate whether language and music share cognitive resources for structural processing. We
report an experiment that used sung materials and manipulated linguistic complexity (subject-extracted relative
clauses, object-extracted relative clauses) and musical complexity (in-key critical note, out-of-key critical note,
auditory anomaly on the critical note involving a loudness increase). The auditory-anomaly manipulation was
included in order to test whether the difference between in-key and out-of-key conditions might be due to any salient,
unexpected acoustic event. The critical dependent measure involved comprehension accuracies to questions
about the propositional content of the sentences asked at the end of each trial. The results revealed an interaction
between linguistic and musical complexity such that the difference between the subject- and object-extracted relative
clause conditions was larger in the out-of-key condition than in the in-key and auditory-anomaly conditions.
These results provide evidence for an overlap in structural processing between language and music
An Outer Arm Dynein Conformational Switch Is Required for Metachronal Synchrony of Motile Cilia in Planaria
Here we use the motile ventral cilia of the planarian S. mediterranea to examine the role of outer arm dynein in the generation and maintenance of metachronal synchrony. We demonstrate that a single dynein light chain plays a mechanosensory role necessary to entrain and maintain the metachronal synchrony of motile cilia
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