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New Constraints for the OnâShore Makran Subduction Zone Crustal Structure
Funder: Institute for Advanced Studies in Basic Sciences; Id: http://dx.doi.org/10.13039/501100007513Abstract: The Makran Subduction Zone is the primary seismic/tsunami hazard of the northwestern Indian Ocean, but little is known of its onâshore seismic structure. We derived a shear wave velocity model extending to > 100 km depth beneath a âŒ400 kmâlong seismic profile oriented parallel to the convergence vector of the Arabian Sea Plate. Receiver function/surface wave analysis shows that the average structure in the coastal region comprises a âŒ22â28 kmâthick low wavespeed sedimentary cover and a 6â8 kmâthick gradient zone overlying > 100 kmâthick high wavespeed upper mantle. The oceanâbasement interface dips gently northward, remaining a positive impedance contrast to âŒ50 km depth at âŒ250 km north of the coast where it disappears as the basaltic/gabbroic oceanic crust has probably transformed to eclogite. Further north, a weak arrival at âŒ5 s in the receiver functions appears, grading northward into the Moho arrival of the continental Iranian Plateau. This disruption in the seismic signature of the Moho occurs in the forearc region where the dip of the subducting oceanic plate steepens. The southern Iranian Plateau's continental crust has an average V s of 3.55 ± 0.05 km sâ1, an almost flat Moho 40â45 km deep, and a subâMoho mantle V s of 3.75 ± 0.05 km sâ1 in the 50â80 km depth range. Weak Moho conversions probably result from âŒ20% serpentinization of peridotite in the mantle wedge. Receiver functions indicate a flat continental Moho â no crustal root beneath the high topography region of the volcanic belt, which therefore must be compensated by low upper mantle densities. The high V p /V s ratio observed for the mantle wedge suggests âŒ1%â2% partial melt
Computed tomography colonography imaging of pneumatosis intestinalis after hyperbaric oxygen therapy: a case report
Acute involution in the tammar wallaby : identification of genes and putative novel milk proteins implicated in mammary gland function
AbstractMarsupials provide a suitable alternative model to studying mammary gland involution. They have evolved a different reproductive strategy from eutherians, giving birth to an altricial young and secreting milk that changes in composition during lactation. In this study, we used a marsupial-specific EST microarray to identify 47 up-regulated genes during mammary gland involution in the tammar wallaby (Macropus eugenii). These include the pro-apoptotic tumour necrosis factor receptor superfamily 21 (TNFRSF21) gene, whose expression in the mammary gland has not previously been reported. Genes encoding putative novel milk proteins which may protect the mammary gland from infection were also found to be up-regulated, such as amiloride binding protein 1 (ABP1), complement component 1QB (C1QB), complement component 4A (C4A) and colony stimulating factor 2 receptor ÎČ (CSF2RÎČ). Our results show that the marsupial reproductive strategy was successfully exploited to identify genes and putative novel milk proteins implicated in mammary gland involution
Dust and gas power-spectrum in M33 (HERM33ES)
Power spectra of de-projected images of late-type galaxies in gas and/or dust
emission are very useful diagnostics of the dynamics and stability of their
interstellar medium. Previous studies have shown that the power spectra can be
approximated as two power-laws, a shallow one at large scales (larger than 500
pc) and a steeper one at small scales, with the break between the two
corresponding to the line-of-sight thickness of the galaxy disk. We present a
thorough analysis of the power spectra of the dust and gas emission at several
wavelengths in the nearby galaxy M33. In particular, we use the recently
obtained images at five wavelengths by PACS and SPIRE onboard Herschel. The
large dynamical range (2-3 dex in scale) of most images allow us to determine
clearly the change in slopes from -1.5 to -4, with some variations with
wavelength. The break scale is increasing with wavelength, from 100 pc at 24
and 100micron to 350 pc at 500micron, suggesting that the cool dust lies in a
thicker disk than the warm dust, may be due to star formation more confined to
the plane. The slope at small scale tends to be steeper at longer wavelength,
meaning that the warmer dust is more concentrated in clumps. Numerical
simulations of an isolated late-type galaxy, rich in gas and with no bulge,
like M33, are carried out, in order to better interpret these observed results.
Varying the star formation and feedback parameters, it is possible to obtain a
range of power-spectra, with two power-law slopes and breaks, which nicely
bracket the data. The small-scale power-law is indeed reflecting the 3D
behaviour of the gas layer, steepening strongly while the feedback smoothes the
structures, by increasing the gas turbulence. M33 appears to correspond to a
fiducial model with an SFR of 0.7 Mo/yr, with 10% supernovae energy
coupled to the gas kinematics.Comment: 11 pages, 24 figures, accepted in Astronomy & Astrophysic
Search for dark matter produced in association with bottom or top quarks in âs = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fbâ1 of protonâproton collision data recorded by the ATLAS experiment at âs = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men