Diffuse Supernova Neutrino Background from extensive core-collapse simulations of 88-100M⊙100 {\rm M}_\odot progenitors

We revisit the diffuse supernova neutrino background in light of recent systematic studies of stellar core collapse that reveal the quantitative impacts of the progenitor conditions on the collapse process. In general, the dependence of the progenitor on the core-collapse neutrino emission is not monotonic in progenitor initial mass, but we show that it can, at first order, be characterized by the core compactness. For the first time, we incorporate the detailed variations in the neutrino emission over the entire mass range $8$-$100 {\rm M}_\odot$, based on (i) a long-term simulation of the core collapse of a $8.8 {\rm M}_\odot$ O-Ne-Mg core progenitor, (ii) over 100 simulations of iron core collapse to neutron stars, and (iii) half a dozen simulations of core collapse to black holes (the "failed channel"). The fraction of massive stars that undergo the failed channel remains uncertain, but in view of recent simulations which reveal high compactness to be conducive to collapse to black holes, we characterize the failed fraction by considering a threshold compactness above which massive stars collapse to black holes and below which the final remnant is a neutron star. We predict that future detections of the diffuse supernova neutrino background may have the power to reveal this threshold compactness, if its value is relatively small as suggested by interpretations of several recent astronomical observations.Comment: 14 pages, 8 figures, accepted for publication in MNRA

Ignition length study of jp-8 + 100 in a supersonic duct

In scramjets, hydrocarbon fuels are being considered for their endothermic potential and for use in flights where compact, volume critical designs are required at flight speeds at Mach 5+. Long-chain hydrocarbon (LCHC) fuels, like aviation kerosene, have handling and storage advantages over hazardous and volatile fuels, like hydrogen, that are more aligned with current flight systems. This research investigates the conditions under which kerosene fuel (JP-8 + 100) may be used in a supersonic duct at a hypervelocity impulse facility. Experimental data on kerosene ignition lengths for temperatures in the range 1100-1550 K, pressure of 1 atm, and equivalence ratios of 0.2-2.5 are compared with ignition delay correlations from literature

A powerful radio-loud quasar at the end of cosmic reionization

We present the discovery of the radio-loud quasar PSO J352.4034-15.3373 at z=5.84 pm 0.02. This quasar is the radio brightest source known, by an order of magnitude, at z~6 with a flux density in the range of 8-100 mJy from 3GHz to 230MHz and a radio loudness parameter R>~1000. This source provides an unprecedented opportunity to study powerful jets and radio-mode feedback at the highest redshifts, and presents the first real chance to probe deep into the neutral intergalactic medium by detecting 21 cm absorption at the end of cosmic reionization.Comment: ApJL accepted on May 8, 2018. See the companion paper by Momjian et a

Eradication of bovine tuberculosis at a herd-level in Madrid, Spain: study of within-herd transmission dynamics over a 12 year period

BACKGROUND Eradication of bovine tuberculosis (bTB) through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12 year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient (β) depending on the herd-type (beef/dairy/bullfighting). In addition, the probability to recover the officially bTB free (OTF) status in infected herds depending on the type of herd and the diagnostic strategy implemented was assessed using Cox proportional hazard models. RESULTS Overall, dairy herds showed higher β (median 4.7) than beef or bullfighting herds (2.3 and 2.2 respectively). Introduction of interferon-gamma (IFN-γ) as an ancillary test produced an apparent increase in the β coefficient regardless of production type, likely due to an increase in diagnostic sensitivity. Time to recover OTF status was also significantly lower in dairy herds, and length of bTB episodes was significantly reduced when the IFN-γ was implemented to manage the outbreak. CONCLUSIONS Our results suggest that bTB spreads more rapidly in dairy herds compared to other herd types, a likely cause being management and demographic-related factors. However, outbreaks in dairy herds can be controlled more rapidly than in typically extensive herd types. Finally, IFN-γ proved its usefulness to rapidly eradicate bTB at a herd-level

Vascular endothelial growth factor (VEGF) expression in locally advanced prostate cancer: secondary analysis of radiation therapy oncology group (RTOG) 8610.

BACKGROUND: Angiogenesis is a key element in solid-tumor growth, invasion, and metastasis. VEGF is among the most potent angiogenic factor thus far detected. The aim of the present study is to explore the potential of VEGF (also known as VEGF-A) as a prognostic and predictive biomarker among men with locally advanced prostate cancer. METHODS: The analysis was performed using patients enrolled on RTOG 8610, a phase III randomized control trial of radiation therapy alone (Arm 1) versus short-term neoadjuvant and concurrent androgen deprivation and radiation therapy (Arm 2) in men with locally advanced prostate carcinoma. Tissue samples were obtained from the RTOG tissue repository. Hematoxylin and eosin slides were reviewed, and paraffin blocks were immunohistochemically stained for VEGF expression and graded by Intensity score (0-3). Cox or Fine and Gray\u27s proportional hazards models were used. RESULTS: Sufficient pathologic material was available from 103 (23%) of the 456 analyzable patients enrolled in the RTOG 8610 study. There were no statistically significant differences in the pre-treatment characteristics between the patient groups with and without VEGF intensity data. Median follow-up for all surviving patients with VEGF intensity data is 12.2 years. Univariate and multivariate analyses demonstrated no statistically significant correlation between the intensity of VEGF expression and overall survival, distant metastasis, local progression, disease-free survival, or biochemical failure. VEGF expression was also not statistically significantly associated with any of the endpoints when analyzed by treatment arm. CONCLUSIONS: This study revealed no statistically significant prognostic or predictive value of VEGF expression for locally advanced prostate cancer. This analysis is among one of the largest sample bases with long-term follow-up in a well-characterized patient population. There is an urgent need to establish multidisciplinary initiatives for coordinating further research in the area of human prostate cancer biomarkers

Joint inversion of Rayleigh wave phase velocity and ellipticity using USArray: Constraining velocity and density structure in the upper crust

Rayleigh wave ellipticity, or H/V ratio, observed on the surface is particularly sensitive to shallow earth structure. In this study, we jointly invert measurements of Rayleigh wave H/V ratio and phase velocity between 24–100 and 8–100 sec period, respectively, for crust and upper mantle structure beneath more than 1000 USArray stations covering the western United States. Upper crustal structure, in particular, is better constrained by the joint inversion compared to inversions based on phase velocities alone. In addition to imaging Vs structure, we show that the joint inversion can be used to constrain Vp/Vs and density in the upper crust. New images of uppermost crustal structure (<3 km depth) are in excellent agreement with known surface features, with pronounced low Vs, low density, and high Vp/Vs anomalies imaged in the locations of several major sedimentary basins including the Williston, Powder River, Green River, Denver, and San Juan basins. These results demonstrate not only the consistency of broadband H/V ratios and phase velocity measurements, but also that their complementary sensitivities have the potential to resolve density and Vp/Vs variations

Acute EBV infection masquerading as "In-situ Follicular Lymphoma": a pitfall in the differential diagnosis of this entity

We present the case of a 30 year-old man who was referred for evaluation of diffuse lymphadenopathy. Six weeks prior, he noticed darkening of his urine associated with pale stools, nausea and an eventual 30 lb weight loss within a month. The initial laboratory findings showed elevation of the liver enzymes. A CT scan showed mesenteric and periaortic lymphadenopathy with the largest lymph node measuring 2.8 cm. Other laboratory results were otherwise unremarkable (including a normal LDH) with the exception of positive serum antibodies against Epstein-Barr virus (EBV) associated antigens (IgM+ and IgG+). An excisional biopsy of 4 of the small neck lymph nodes showed a normal architecture with prominent follicles and an intact capsule. But, by immunohistochemistry two of the follicles showed aberrant coexpression of BCL-2, in addition to CD10 and BCL-6. In-situ hybridization for early Epstein-Barr virus mRNA (EBER) and immunohistochemistry for latent membrane protein-1 (LMP-1) stained both scattered positive cells, as well as BCL-2 positive B-cells. Although an original diagnosis of in-situ follicular lymphoma was favored at an outside facility, additional interphase fluorescence in situ hybridization (FISH) studies for t(14;18);(IGH-BCL2) rearrangement (performed on the BCL-2 + follicles microdissected from the tissue block; Abott probe dual colour fusion) and molecular studies (IGH gene rearrangement by PCR, also performed on the microdissected follicles) were negative. Serologic studies (positive EBV antibodies) and immunostains in conjunction with the molecular studies confirmed the reactive nature of the changes. Our case also shows direct immunopathogenic evidence of BCL-2 expression among the EBV-infected cells, which has to our knowledge not been previously documented in vivo. A diagnosis of EBV infection should, therefore, be considered when confronted with BCL-2 expression in germinal centers, particularly in younger individuals, as the diagnosis of FLIS may lead to extensive and invasive haematologic work-ups. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/132365631894006