The sex locus is tightly linked to factors conferring sex-specific lethal effects in the mosquito Aedes aegypti

In many taxa, sex chromosomes are heteromorphic and largely non-recombining. Evolutionary models predict that spread of recombination suppression on the Y chromosome is fueled by the accumulation of sexually antagonistic alleles in close linkage to the sex determination region. However, empirical evidence for the existence of sexually antagonistic alleles is scarce. In the mosquito Aedes aegypti, the sex-determining chromosomes are homomorphic. The region of suppressed recombination, which surrounds the male-specific sex-determining gene, remains very small, despite ancient origin of the sex chromosomes in the Aedes lineage. We conducted a genetic analysis of the A. aegypti chromosome region tightly linked to the sex locus. We used a strain with an enhanced green fluorescent protein (EGFP)-tagged transgene inserted near the male-determining gene to monitor crossing-over events close to the boundary of the sex-determining region (SDR), and to trace the inheritance pattern of the transgene in relation to sex. In a series of crossing experiments involving individuals with a recombinant sex chromosome we found developmental abnormalities leading to 1:2 sex biases, caused by lethality of half of the male or female progeny. Our results suggest that various factors causing sex-specific lethal effects are clustered within the neighborhood of the SDR, which in the affected sex are likely lost or gained through recombination, leading to death. These may include genes that are recessive lethal, vital for development and/or sexually antagonistic. The sex chromosome fragment in question represents a fascinating test case for the analysis of processes that shape stable boundaries of a non-recombining region

Measurement of single π0 production by coherent neutral-current ν Fe interactions in the MINOS Near Detector

Forward single π0 production by coherent neutral-current interactions, νA→νAπ0, is investigated using a 2.8×1020 protons-on-target exposure of the MINOS Near Detector. For single-shower topologies, the event distribution in production angle exhibits a clear excess above the estimated background at very forward angles for visible energy in the range 1-8 GeV. Cross sections are obtained for the detector medium comprised of 80% iron and 20% carbon nuclei with =48, the highest- target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single π0 production initiated by the νμ flux of the NuMI low-energy beam with mean (mode) Eν of 4.9 GeV (3.0 GeV), is 77.6±5.0(stat)-16.8+15.0(syst)×10-40 cm2 pernucleus. The results are in good agreement with predictions of the Berger-Sehgal model

Search for Sterile Neutrinos Mixing with Muon Neutrinos in MINOS

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a νμ-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56 × 10^20 protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ24 and Δm41^2 and set limits on parameters of the four-dimensional Pontecorvo-Maki- Nakagawa-Sakata matrix, |Uμ4|2 and |Uτ4|2, under the assumption that mixing between νe and νs is negligible (|Ue4|^2 = 0). No evidence for νμ → νs transitions is found and we set a world-leading limit on θ24 for values of Δm41^2 ≲ 1 eV^2

Measurement of the multiple-muon charge ratio in the MINOS Far Detector

The charge ratio, Rμ=Nμ+/Nμ−, for cosmogenic multiple-muon events observed at an underground depth of 2070 mwe has been measured using the magnetized MINOS Far Detector. The multiple-muon events, recorded nearly continuously from August 2003 until April 2012, comprise two independent data sets imaged with opposite magnetic field polarities, the comparison of which allows the systematic uncertainties of the measurement to be minimized. The multiple-muon charge ratio is determined to be Rμ=1.104±0.006(stat)+0.009−0.010(syst). This measurement complements previous determinations of single-muon and multiple-muon charge ratios at underground sites and serves to constrain models of cosmic-ray interactions at TeV energies

Search for flavor-changing nonstandard neutrino interactions using nu(e) appearance in MINOS

We report new constraints on flavor-changing nonstandard neutrino interactions from the MINOS long-baseline experiment using νe and ¯νe appearance candidate events from predominantly νμ and ¯νμ beams. We used a statistical selection algorithm to separate νe candidates from background events, enabling an analysis of the combined MINOS neutrino and antineutrino data. We observe no deviations from standard neutrino mixing, and thus place constraints on the nonstandard interaction matter effect, |ϵeτ|, and phase, (δCP+δeτ), using a 30-bin likelihood fit

Precision measurement of the speed of propagation of neutrinos using the MINOS detectors

We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino speed and the speed of light is determined to be (v/c−1)=(1.0±1.1)×10−6, consistent with relativistic neutrinos

Limits on active to sterile neutrino oscillations from disappearance searches in the MINOS, Daya Bay, and bugey-3 experiments

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^2 2θμe are set over 6 orders of magnitude in the sterile mass-squared splitting Δm^2 41. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm^2 41 < 0.8 eV^2 at 95% CLs

Search for Sterile Neutrinos in MINOS and MINOS plus Using a Two-Detector Fit

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36 × 10 20 protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3 + 1 model. The most stringent limit to date is set on the mixing parameter sin 2 θ 24 for most values of the sterile neutrino mass splitting Δ m 2 41 > 10 − 4     eV 2

Search for Sterile Neutrinos in MINOS and MINOS+ Using a Two-Detector Fit.

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4}  eV^{2}

Congenital Diaphragmatic hernia – a review

Congenital Diaphragmatic hernia (CDH) is a condition characterized by a defect in the diaphragm leading to protrusion of abdominal contents into the thoracic cavity interfering with normal development of the lungs. The defect may range from a small aperture in the posterior muscle rim to complete absence of diaphragm. The pathophysiology of CDH is a combination of lung hypoplasia and immaturity associated with persistent pulmonary hypertension of newborn (PPHN) and cardiac dysfunction. Prenatal assessment of lung to head ratio (LHR) and position of the liver by ultrasound are used to diagnose and predict outcomes. Delivery of infants with CDH is recommended close to term gestation. Immediate management at birth includes bowel decompression, avoidance of mask ventilation and endotracheal tube placement if required. The main focus of management includes gentle ventilation, hemodynamic monitoring and treatment of pulmonary hypertension followed by surgery. Although inhaled nitric oxide is not approved by FDA for the treatment of PPHN induced by CDH, it is commonly used. Extracorporeal membrane oxygenation (ECMO) is typically considered after failure of conventional medical management for infants ≥ 34 weeks’ gestation or with weight >2 kg with CDH and no associated major lethal anomalies. Multiple factors such as prematurity, associated abnormalities, severity of PPHN, type of repair and need for ECMO can affect the survival of an infant with CDH. With advances in the management of CDH, the overall survival has improved and has been reported to be 70-90% in non-ECMO infants and up to 50% in infants who undergo ECMO