In this paper, we present the first observations of the Ophiuchus molecular cloud performed as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) with the SCUBA-2 instrument. We ...demonstrate methods for combining these data with previous HARP CO, Herschel, and IRAM N2H+ observations in order to accurately quantify the properties of the SCUBA-2 sources in Ophiuchus. We produce a catalogue of all of the sources found by SCUBA-2. We separate these into protostars and starless cores. We list all of the starless cores and perform a full virial analysis, including external pressure. This is the first time that external pressure has been included in this level of detail. We find that the majority of our cores are either bound or virialized. Gravitational energy and external pressure are on average of a similar order of magnitude, but with some variation from region to region. We find that cores in the Oph A region are gravitationally bound prestellar cores, while cores in the Oph C and E regions are pressure-confined. We determine that N2H+ is a good tracer of the bound material of prestellar cores, although we find some evidence for N2H+ freeze-out at the very highest core densities. We find that non-thermal linewidths decrease substantially between the gas traced by C18O and that traced by N2H+, indicating the dissipation of turbulence at higher densities. We find that the critical Bonnor–Ebert stability criterion is not a good indicator of the boundedness of our cores. We detect the pre-brown dwarf candidate Oph B-11 and find a flux density and mass consistent with previous work. We discuss regional variations in the nature of the cores and find further support for our previous hypothesis of a global evolutionary gradient across the cloud from south-west to north-east, indicating sequential star formation across the region.
Probiotics are living microorganisms that are generally thought of as being beneficial to the recipient. They have been shown to be effective in people with acute infectious diarrhoea, and ...cost-effective in antibiotic-associated diarrhoea. Probiotics may have a role in people with cancer, as various cancer treatments often lead to diarrhoea. However, as people with cancer are often immunocompromised, it is important to assess for adverse events (AEs) such as infection, which could potentially be a consequence of deliberate ingestion of living microorganisms.
A systematic review was carried out to collect, analyse and synthesise all available data on the efficacy and safety of probiotics in people with cancer (PROSPERO registration: CRD42012003454). Randomised, controlled trials, identified through screening multiple databases and grey literature, were included for analysing efficacy, while all studies were included for the analysis of safety of probiotics. Primary outcomes were the reduction in duration, severity and incidence of antibiotic-associated diarrhoea and chemotherapy-associated diarrhoea, and AEs, especially probiotic-associated infection. Where possible, data were combined for meta-analysis by a random-effects model, assessing causes of heterogeneity, including differences in strains, dosage and patient characteristics.
Eleven studies (N = 1557 participants) were included for assessing efficacy. Results show that probiotics may reduce the severity and frequency of diarrhoea in patients with cancer and may reduce the requirement for anti-diarrhoeal medication, but more studies are needed to assess the true effect. For example comparing probiotic use to control 25 groups on effect on Common Toxicity Criteria ≥2 grade diarrhoea, odds ratio (OR) = 0.32 95% confidence interval (CI) of 0.13–0.79; P = 0.01. Seventeen studies (N = 1530) were included in the safety analysis. Five case reports showed probiotic-related bacteraemia/fungaemia/positive blood cultures.
Probiotics may be a rare cause of sepsis. Further evidence needs to be collated to determine whether probiotics provide a significant overall benefit for people with cancer.
We report the observation of gravitational waves from two compact binary coalescences in LIGO's and Virgo's third observing run with properties consistent with neutron star-black hole (NSBH) ...binaries. The two events are named GW200105_162426 and GW200115_042309, abbreviated as GW200105 and GW200115; the first was observed by LIGO Livingston and Virgo, and the second by all three LIGO-Virgo detectors. The source of GW200105 has component masses 8.9(exp +1.2/-1.5) M⨀ and 1.9(exp +0.3/-0.2) M⨀, whereas the source of GW200115 has component masses 5.7(exp +1.8/-2.1) M⨀ and 1.5(exp +0.7/-0.3) M⨀ (all measurements quoted at the 90% credible level). The probability that the secondary's mass is below the maximal mass of a neutron star is 89%-96% and 87%-98%, respectively, for GW200105 and GW200115, with the ranges arising from different astrophysical assumptions. The source luminosity distances are 280(exp +110/-110) Mpc and 300(+150/-100) Mpc, respectively. The magnitude of the primary spin of GW200105 is less than 0.23 at the 90% credible level, and its orientation is unconstrained. For GW200115, the primary spin has a negative spin projection onto the orbital angular momentum at 88% probability. We are unable to constrain the spin or tidal deformation of the secondary component for either event. We infer an NSBH merger rate density of 45(exp +75/-33) Gpc(exp -3) yr(exp -1) when assuming that GW200105 and GW200115 are representative of the NSBH population, or 130(+112/-69) Gpc(exp -3) yr(exp -1) under the assumption of a broader distribution of component masses.
We report the observation of a compact binary coalescence involving a 22.2-24.3 M black hole and a compact object with a mass of 2.50-2.67 M (all measurements quoted at the 90% credible level). The ...gravitational-wave signal, GW190814, was observed during LIGO's and Virgo's third observing run on 2019 August 14 at 21:10:39 UTC and has a signal-to-noise ratio of 25 in the three-detector network. The source was localized to 18.5 deg2 at a distance of Mpc; no electromagnetic counterpart has been confirmed to date. The source has the most unequal mass ratio yet measured with gravitational waves, , and its secondary component is either the lightest black hole or the heaviest neutron star ever discovered in a double compact-object system. The dimensionless spin of the primary black hole is tightly constrained to ≤0.07. Tests of general relativity reveal no measurable deviations from the theory, and its prediction of higher-multipole emission is confirmed at high confidence. We estimate a merger rate density of 1-23 Gpc−3 yr−1 for the new class of binary coalescence sources that GW190814 represents. Astrophysical models predict that binaries with mass ratios similar to this event can form through several channels, but are unlikely to have formed in globular clusters. However, the combination of mass ratio, component masses, and the inferred merger rate for this event challenges all current models of the formation and mass distribution of compact-object binaries.
ABSTRACT We report abundances of elements from 26Fe to 40Zr in the cosmic radiation measured by the SuperTIGER (Trans-Iron Galactic Element Recorder) instrument during 55 days of exposure on a ...long-duration balloon flight over Antarctica. These observations resolve elemental abundances in this charge range with single-element resolution and good statistics. These results support a model of cosmic ray origin in which the source material consists of a mixture of % material from massive stars and ∼81% normal interstellar medium material with solar system abundances. The results also show a preferential acceleration of refractory elements (found in interstellar dust grains) by a factor of ∼4 over volatile elements (found in interstellar gas) ordered by atomic mass (A). Both the refractory and volatile elements show a mass-dependent enhancement with similar slopes.
Whilst initial rates of insulin independence following islet transplantation are encouraging, long‐term function using the Edmonton Protocol remains a concern. The aim of this single‐arm, multicenter ...study was to evaluate an immunosuppressive protocol of initial antithymocyte globulin (ATG), tacrolimus and mycophenolate mofetil (MMF) followed by switching to sirolimus and MMF. Islets were cultured for 24 h prior to transplantation. The primary end‐point was an HbA1c of <7% and cessation of severe hypoglycemia. Seventeen recipients were followed for ≥12 months. Nine islet preparations were transported interstate for transplantation. Similar outcomes were achieved at all three centers. Fourteen of the 17 (82%) recipients achieved the primary end‐point. Nine (53%) recipients achieved insulin independence for a median of 26 months (range 7–39 months) and 6 (35%) remain insulin independent. All recipients were C‐peptide positive for at least 3 months. All subjects with unstimulated C‐peptide >0.2 nmol/L had cessation of severe hypoglycemia. Nine of the 17 recipients tolerated switching from tacrolimus to sirolimus with similar graft outcomes. There was a small but significant reduction in renal function in the first 12 months. The combination of islet culture, ATG, tacrolimus and MMF is a viable alternative for islet transplantation.
This multicenter Australian trial of islet transplantation alone, using antithymocyte globulin, tacrolimus, and mycophenolate mofetil, confi rms improving outcomes for the procedure and demonstrates that it is possible to develop new islet centers, thereby improving accessibility for patients.
We report on the population of 47 compact binary mergers detected with a false-alarm rate of <1yr^(−1) in the second LIGO–Virgo Gravitational-Wave Transient Catalog. We observe several ...characteristics of the merging binary black hole (BBH) population not discernible until now. First, the primary mass spectrum contains structure beyond a power law with a sharp high-mass cutoff; it is more consistent with a broken power law with a break at 39.7^(+20.3)(-9.1)M or a power law with a Gaussian feature peaking at 33.1^(+4.0)(-5.6)M (90% credible interval). While the primary mass distribution must extend to ~65M or beyond, only 2.9^(+3.5)(-1.7)M% of systems have primary masses greater than 45M. Second, we find that a fraction of BBH systems have component spins misaligned with the orbital angular momentum, giving rise to precession of the orbital plane. Moreover, 12% to 44% of BBH systems have spins tilted by more than 90°, giving rise to a negative effective inspiral spin parameter, χeff. Under the assumption that such systems can only be formed by dynamical interactions, we infer that between 25% and 93% of BBHs with nonvanishing |χeff| > 0.01 are dynamically assembled. Third, we estimate merger rates, finding RBBH = 23.9^(+14.3)(-8.6) Gpc^(-3) yr^(-1) for BBHs and RBNS = 320^(+490)(-240) Gpc^(-3) yr^(-1) for binary neutron stars. We find that the BBH rate likely increases with redshift (85% credibility) but not faster than the star formation rate (86% credibility). Additionally, we examine recent exceptional events in the context of our population models, finding that the asymmetric masses of GW190412 and the high component masses of GW190521 are consistent with our models, but the low secondary mass of GW190814 makes it an outlier.
Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the ...Gemini Planet Imager, we discovered a planet orbiting the ∼20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption. Modeling of the spectra and photometry yields a luminosity (normalized by the luminosity of the Sun) of 1.6 to 4.0 × 10–6 and an effective temperature of 600 to 750 kelvin. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold-start" core-accretion process that may have formed Jupiter.
Sources of Antimicrobial Resistance Woolhouse, Mark E. J.; Ward, Melissa J.
Science (American Association for the Advancement of Science),
09/2013, Letnik:
341, Številka:
6153
Journal Article
Recenzirano
The relentless rise in levels of antimicrobial resistance is an unfolding global public health crisis (1). Resistance to frontline antimicrobials such as fluoroquinolones, third- and ...fourth-generation cephalosporins, and carbapenems is a particular concern, as is multidrug resistance. The antimicrobial resistance problem is not confined to human medicine: Comparable quantities of antimicrobials are used in livestock production, and resistance is rife in that setting, too, even on organic farms that restrict drug usage (2). Such observations have led to debate about whether antimicrobial resistance in farm animals is an important source of antimicrobial resistance in humans (3, 4). On page 1514 of this issue, Mather et al. (5) shed light on this important question in the context of Salmonella Typhimurium DT104 in humans and cattle in Scotland.
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