A Search for Pulsars in Quiescent Soft X-Ray Transients. I

We have carried out a deep search at 1.4 GHz for radio pulsed emission from six soft X-ray transient sources observed during their X-ray quiescent phase. The commonly accepted model for the formation of the millisecond radio pulsars predicts the presence of a rapidly rotating, weakly magnetized neutron star in the core of these systems. The sudden drop in accretion rate associated with the end of an X-ray outburst causes the Alfv\`en surface to move outside the light cylinder, allowing the pulsar emission process to operate. No pulsed signal was detected from the sources in our sample. We discuss several mechanisms that could hamper the detection and suggest that free-free absorption from material ejected from the system by the pulsar radiation pressure could explain our null result.Comment: accepted by Ap

EFFICACY OF PNEUMATIC DILATATION FOR THE TREATMENT OF IDIOPATIC ACHALASIA: A SINGLE-CENTRE EXPERIENCE

Pneumatic dilatation (PD) and surgical miotomy (SM) are presentely the best treastments for untreated achalasia, with similar efficacy. There is no information on the relative efficacy of PD in younger compared to older patients. Aim of our study was to compare success rate and safety of PD patients under fifty years old in our Unit with graded PD under fluoroscopic view. Five male and 15 female with a median age of 47 years were treated. Twelve patients were less than fifthy years old (group I) while 8 were older (group II). Median dysphagia questionnaire score was 14 and 13 in group I and II respectively. Technical success was achieved in all patients. Seven patients were previously treated through other techniques. In group I all patients achieved a complete remission of symptoms with significant decrease of the dysphagia questionnaire (3). in group II all patients achieved a complete remissionof symptoms with significant decrease of the dysphagia questionnaire score (4,5) but 3 of them repeated the procedure. In boths groups the efficacy of the dilation was radiologically confirmed. Neither early nor late complications were reported in either groups. In our experience PD was an effective and safe procedure both in young and old patients although the older group had more recurrences, all successfully re-dilated

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Current knowledge of pituitary adenylate cyclase activating polypeptide (PACAP) in articular cartilage

Pituitary adenylate cyclase activating polypeptide (PACAP) is an evolutionally well conserved neuropeptide, mainly expressed by neuronal and peripheral cells. It proves to be an interesting object of study both for its trophic functions during the development of several tissues and for its protective effects against oxidative stress, hypoxia, inflammation and apoptosis in different degenerative diseases. This brief review summarises the recent findings concerning the role of PACAP in the articular cartilage. PACAP and its receptors are expressed during chondrogenesis and are shown to activate the pathways involved in regulating cartilage development. Moreover, this neuropeptide proves to be chondroprotective against those stressors that determine cartilage degeneration and contribute to the onset of osteoarthritis (OA), the most common form of degenerative joint disease. Indeed, the degenerated cartilage exhibits low levels of PACAP, suggesting that its endogenous levels in adult cartilage may play an essential role in maintaining physiological properties. Thanks to its peculiar characteristics, exogenous administration of PACAP could be suggested as a potential tool to slow down the progression of OA and for cartilage regeneration approaches

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

Molecular Dynamics of Mesophilic-Like Mutants of a Cold-Adapted Enzyme: Insights into Distal Effects Induced by the Mutations

Networks and clusters of intramolecular interactions, as well as their “communication” across the three-dimensional architecture have a prominent role in determining protein stability and function. Special attention has been dedicated to their role in thermal adaptation. In the present contribution, seven previously experimentally characterized mutants of a cold-adapted α-amylase, featuring mesophilic-like behavior, have been investigated by multiple molecular dynamics simulations, essential dynamics and analyses of correlated motions and electrostatic interactions. Our data elucidate the molecular mechanisms underlying the ability of single and multiple mutations to globally modulate dynamic properties of the cold-adapted α-amylase, including both local and complex unpredictable distal effects. Our investigation also shows, in agreement with the experimental data, that the conversion of the cold-adapted enzyme in a warm-adapted variant cannot be completely achieved by the introduction of few mutations, also providing the rationale behind these effects. Moreover, pivotal residues, which are likely to mediate the effects induced by the mutations, have been identified from our analyses, as well as a group of suitable candidates for protein engineering. In fact, a subset of residues here identified (as an isoleucine, or networks of mesophilic-like salt bridges in the proximity of the catalytic site) should be considered, in experimental studies, to get a more efficient modification of the features of the cold-adapted enzyme

Respiratory Trajectories in Type 2 and 3 Spinal Muscular Atrophy in the iSMAC Cohort Study.

Objective To describe the respiratory trajectories and their correlation with motor function in an international pediatric cohort of patients with type 2 and nonambulant type 3 spinal muscular atrophy (SMA). Methods This was an 8-year retrospective observational study of patients in the International SMA Consortium (iSMAc) natural history study. We retrieved anthropometrics, forced vital capacity (FVC) absolute, FVC percent predicted (FVC%P), and noninvasive ventilation (NIV) requirement. Hammersmith Functional Motor Scale (HFMS) and revised Performance of Upper Limb (RULM) scores were correlated with respiratory function. We excluded patients in interventional clinical trials and on nusinersen commercial therapy. Results There were 437 patients with SMA: 348 with type 2 and 89 with nonambulant type 3. Mean age at first visit was 6.9 (+/- 4.4) and 11.1 (+/- 4) years. In SMA type 2, FVC%P declined by 4.2%/y from 5 to 13 years, followed by a slower decline (1.0%/y). In type 3, FVC%P declined by 6.3%/y between 8 and 13 years, followed by a slower decline (0.9%/y). Thirty-nine percent with SMA type 2% and 9% with type 3 required NIV at a median age 5.0 (1.8-16.6) and 15.1 (13.8-16.3) years. Eighty-four percent with SMA type 2% and 80% with type 3 had scoliosis; 54% and 46% required surgery, which did not significantly affect respiratory decline. FVC%P positively correlated with HFMS and RULM scores in both subtypes. Conclusions In SMA type 2 and nonambulant type 3, lung function declines differently, with a common leveling after age 13 years. Lung and motor function correlated in both subtypes. Our data further define themilder SMA phenotypes and provide information to benchmark the long-term efficacy of new treatments for SMA

Transient radio bursts from rotating neutron stars

The `radio sky' is relatively unexplored for transient signals, although the potential of radio-transient searches is high, as demonstrated recently by the discovery of a previously unknown type of source which varies on timescales of minutes to hours. Here we report a new large-scale search for radio sources varying on much shorter timescales. This has revealed 11 objects characterized by single, dispersed bursts having durations between 2 and 30 ms. The average time intervals between bursts range from 4 minutes to 3 hours, with radio emission typically detectable for < 1 s per day. From an analysis of the burst arrival times, we have identified periodicities in the range 0.4 - 7 s for ten of the 11 sources, suggesting a rotating neutron star origin. Despite the small number of sources presently detected, their ephemeral nature implies a total Galactic population which significantly exceeds that of the regularly pulsing radio pulsars. Five of the ten sources have periods greater than 4 s, and period derivatives have been measured for three of the sources, with one having a very high inferred magnetic field of 5e13 G, suggesting that this new population is related to other classes of isolated neutron stars observed at X-ray and gamma-ray wavelengths.Comment: 10 pages, 4 figures. Accepted by Natur

The IgA nephropathy Biobank. An important starting point for the genetic dissection of a complex trait

BACKGROUND: IgA nephropathy (IgAN) or Berger's disease, is the most common glomerulonephritis in the world diagnosed in renal biopsied patients. The involvement of genetic factors in the pathogenesis of the IgAN is evidenced by ethnic and geographic variations in prevalence, familial clustering in isolated populations, familial aggregation and by the identification of a genetic linkage to locus IGAN1 mapped on 6q22–23. This study seems to imply a single major locus, but the hypothesis of multiple interacting loci or genetic heterogeneity cannot be ruled out. The organization of a multi-centre Biobank for the collection of biological samples and clinical data from IgAN patients and relatives is an important starting point for the identification of the disease susceptibility genes. DESCRIPTION: The IgAN Consortium organized a Biobank, recruiting IgAN patients and relatives following a common protocol. A website was constructed to allow scientific information to be shared between partners and to divulge obtained data (URL: ). The electronic database, the core of the website includes data concerning the subjects enrolled. A search page gives open access to the database and allows groups of patients to be selected according to their clinical characteristics. DNA samples of IgAN patients and relatives belonging to 72 multiplex extended pedigrees were collected. Moreover, 159 trios (sons/daughters affected and healthy parents), 1068 patients with biopsy-proven IgAN and 1040 healthy subjects were included in the IgAN Consortium Biobank. Some valuable and statistically productive genetic studies have been launched within the 5(th )Framework Programme 1998–2002 of the European project No. QLG1-2000-00464 and preliminary data have been published in "Technology Marketplace" website: . CONCLUSION: The first world IgAN Biobank with a readily accessible database has been constituted. The knowledge gained from the study of Mendelian diseases has shown that the genetic dissection of a complex trait is more powerful when combined linkage-based, association-based, and sequence-based approaches are performed. This Biobank continuously expanded contains a sample size of adequately matched IgAN patients and healthy subjects, extended multiplex pedigrees, parent-child trios, thus permitting the combined genetic approaches with collaborative studies