Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

The empirical process of a short-range dependent stationary sequence under Gaussian subordination

Consider the stationary sequence X 1 = G ( Z 1 ), X 2 = G ( Z 2 ),..., where G (·) is an arbitrary Borel function and Z 1 , Z 2 ,... is a mean-zero stationary Gaussian sequence with covariance function r(k)=E ( Z 1 Z k +1 ) satisfying r (0)=1 and ∑ k =1 ∞ | r ( k )| m < ∞, where, with I {·} denoting the indicator function and F (·) the continuous marginal distribution function of the sequence { X n }, the integer m is the Hermite rank of the family { I { G (·) ≦ x } − F ( x ): x ∈ R }. Let F n (·) be the empirical distribution function of X 1 ,..., X n . We prove that, as n →∞, the empirical process n 1/2 { F n (·)- F (·)} converges in distribution to a Gaussian process in the space D [−∞,∞].Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47644/1/440_2005_Article_BF01303800.pd

Evaluation of antibody response to Plasmodium falciparum in children according to exposure of Anopheles gambiae s.l or Anopheles funestus vectors

<p>Abstract</p> <p>Background</p> <p>In sub-Saharan areas, malaria transmission was mainly ensured by <it>Anopheles. gambiae </it>s.l. and <it>Anopheles. funestus </it>vectors. The immune response status to <it>Plasmodium falciparum </it>was evaluated in children living in two villages where malaria transmission was ensured by dissimilar species of <it>Anopheles </it>vectors (<it>An. funestus vs An. gambiae </it>s.l.).</p> <p>Methods</p> <p>A multi-disciplinary study was performed in villages located in Northern Senegal. Two villages were selected: Mboula village where transmission is strictly ensured by <it>An. gambiae </it>s.l. and Gankette Balla village which is exposed to several <it>Anopheles </it>species but where <it>An. funestus </it>is the only infected vector found. In each village, a cohort of 150 children aged from one to nine years was followed during one year and IgG response directed to schizont extract was determined by ELISA.</p> <p>Results</p> <p>Similar results of specific IgG responses according to age and <it>P. falciparum </it>infection were observed in both villages. Specific IgG response increased progressively from one-year to 5-year old children and then stayed high in children from five to nine years old. The children with <it>P. falciparum </it>infection had higher specific antibody responses compared to negative infection children, suggesting a strong relationship between production of specific antibodies and malaria transmission, rather than protective immunity. In contrast, higher variation of antibody levels according to malaria transmission periods were found in Mboula compared to Gankette Balla. In Mboula, the peak of malaria transmission was followed by a considerable increase in antibody levels, whereas low and constant anti-malaria IgG response was observed throughout the year in Gankette Balla.</p> <p>Conclusion</p> <p>This study shows that the development of anti-malaria antibody response was profoundly different according to areas where malaria exposure is dependent with different <it>Anopheles </it>species. These results are discussed according to i) the use of immunological tool for the evaluation of malaria transmission and ii) the influence of <it>Anopheles </it>vectors species on the regulation of antibody responses to <it>P. falciparum</it>.</p

Surgical outcomes for colon and rectal cancer over a decade: results from a consecutive monocentric experience in 902 unselected patients

<p>Abstract</p> <p>Background</p> <p>This study evaluates the surgical morbidity and long-term outcome of colorectal cancer surgery in an unselected group of patients treated over the period 1994–2003.</p> <p>Methods</p> <p>A consecutive series of 902 primary colorectal cancer patients (489 M, 413 F; mean age: 63 years ± 11 years, range: 24–88 years) was evaluated and prospectively followed in a university hospital (mean follow-up 36 ± 24 months; range: 3–108 months). Perioperative mortality, morbidity, overall survival, curative resection rates, recurrence rates were analysed.</p> <p>Results</p> <p>Of the total, 476 colorectal cancers were localized to the colon (CC, 53%), 406 to the rectum (RC, 45%), 12 (1%) were multicentric, and 8 were identified as part of HNPCC (1%). Combining all tumours, there were 186 cancers (20.6%) defined as UICC stage I, 235 (26.1%) stage II, 270 (29.9%) stage III and 187 (20.6%) stage IV cases. Twenty-four (2.7%) cases were of undetermined stage. Postoperative complications occurred in 38% of the total group (37.8% of CC cases, 37.2% of the RC group, 66.7% of the synchronous cancer patients and 50% of those with HNPCC, p = 0.19) Mortality rate was 0.8%, (1.3% for colon cancer, 0% for rectal cancer; p = 0.023). Multivisceral resection was performed in 14.3% of cases. Disease-free survival in cases resected for cure was 73% at 5-years and 72% at 8 years. The 5- and 8-year overall survival rates were 71% and 61% respectively (total cases). At 5-year analysis, overall survival rates are 97% for stage I disease, 87% for stage II, 73% for stage III and 22% for stage IV respectively (p < 0.0001). The 5-year overall survival rates showed a marked difference in R0, R1+R2 and non resected patients (82%, 35% and 0% respectively, p < 0.0001). On multivariate analysis, resection for cure and stage at presentation but not tumour site (colon vs. rectum) were independent variables for overall survival (p < 0.0001).</p> <p>Conclusion</p> <p>A prospective, uniform follow-up policy used in a single institution over the last decade provides evidence of quality assurance in colorectal cancer surgery with high rates of resection for cure where only stage at presentation functions as an independent variable for cancer-related outcome.</p

Abnormal Brain Activation in Neurofibromatosis Type 1: A Link between Visual Processing and the Default Mode Network

Neurofibromatosis type 1 (NF1) is one of the most common single gene disorders affecting the human nervous system with a high incidence of cognitive deficits, particularly visuospatial. Nevertheless, neurophysiological alterations in low-level visual processing that could be relevant to explain the cognitive phenotype are poorly understood. Here we used functional magnetic resonance imaging (fMRI) to study early cortical visual pathways in children and adults with NF1. We employed two distinct stimulus types differing in contrast and spatial and temporal frequencies to evoke relatively different activation of the magnocellular (M) and parvocellular (P) pathways. Hemodynamic responses were investigated in retinotopically-defined regions V1, V2 and V3 and then over the acquired cortical volume. Relative to matched control subjects, patients with NF1 showed deficient activation of the low-level visual cortex to both stimulus types. Importantly, this finding was observed for children and adults with NF1, indicating that low-level visual processing deficits do not ameliorate with age. Moreover, only during M-biased stimulation patients with NF1 failed to deactivate or even activated anterior and posterior midline regions of the default mode network. The observation that the magnocellular visual pathway is impaired in NF1 in early visual processing and is specifically associated with a deficient deactivation of the default mode network may provide a neural explanation for high-order cognitive deficits present in NF1, particularly visuospatial and attentional. A link between magnocellular and default mode network processing may generalize to neuropsychiatric disorders where such deficits have been separately identified

Gene expression patterns associated with blood-feeding in the malaria mosquito Anopheles gambiae

BACKGROUND: Blood feeding, or hematophagy, is a behavior exhibited by female mosquitoes required both for reproduction and for transmission of pathogens. We determined the expression patterns of 3,068 ESTs, representing ~2,000 unique gene transcripts using cDNA microarrays in adult female Anopheles gambiae at selected times during the first two days following blood ingestion, at 5 and 30 min during a 40 minute blood meal and at 0, 1, 3, 5, 12, 16, 24 and 48 hours after completion of the blood meal and compared their expression to transcript levels in mosquitoes with access only to a sugar solution. RESULTS: In blood-fed mosquitoes, 413 unique transcripts, approximately 25% of the total, were expressed at least two-fold above or below their levels in the sugar-fed mosquitoes, at one or more time points. These differentially expressed gene products were clustered using k-means clustering into Early Genes, Middle Genes, and Late Genes, containing 144, 130, and 139 unique transcripts, respectively. Several genes from each group were analyzed by quantitative real-time PCR in order to validate the microarray results. CONCLUSION: The expression patterns and annotation of the genes in these three groups (Early, Middle, and Late genes) are discussed in the context of female mosquitoes' physiological responses to blood feeding, including blood digestion, peritrophic matrix formation, egg development, and immunity

Erratum: "Searches for Gravitational Waves from Known Pulsars at Two Harmonics in 2015–2017 LIGO Data" (2019, ApJ, 879, 10)

This is a correction for 2019 ApJ 879 1

All-sky search for continuous gravitational waves from isolated neutron stars in the early O3 LIGO data

We report on an all-sky search for continuous gravitational waves in the frequency band 20-2000 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Such a signal could be produced by a nearby, spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the LIGO data from the first six months of Advanced LIGO's and Advanced Virgo's third observational run, O3. No periodic gravitational wave signals are observed, and 95% confidence-level (C.L.) frequentist upper limits are placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼1.7×10-25 near 200 Hz. For a circularly polarized source (most favorable orientation), the lowest upper limits are ∼6.3×10-26. These strict frequentist upper limits refer to all sky locations and the entire range of frequency derivative values. For a population-averaged ensemble of sky locations and stellar orientations, the lowest 95% C.L. upper limits on the strain amplitude are ∼1.4×10-25. These upper limits improve upon our previously published all-sky results, with the greatest improvement (factor of ∼2) seen at higher frequencies, in part because quantum squeezing has dramatically improved the detector noise level relative to the second observational run, O2. These limits are the most constraining to date over most of the parameter space searched

Combination of searches for heavy spin-1 resonances using 139 fb−1 of proton-proton collision data at √s = 13 TeV with the ATLAS detector

A combination of searches for new heavy spin-1 resonances decaying into diferent pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fb−1 of proton-proton collisions at √ s = 13 TeV collected during 2015–2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb, tt¯, and tb) or third-generation leptons (τν and τ τ ) are included in this kind of combination for the frst time. A simplifed model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confdence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion