To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
To evaluate the long-term safety and efficacy of adjunctive aripiprazole (ARI) to lithium (LI) or valproate (VAL) in delaying time to relapse in bipolar I disorder.
Bipolar I disorder subjects with a current manic or mixed episode received LI or VAL for at least 2 weeks; inadequate responders (YMRS score ≥ 16 and ≤35% decrease from baseline at 2 weeks) received adjunctive ARI. Subjects maintaining mood stability (YMRS and MADRS ≤ 12 for 12 consecutive weeks) were randomised 1:1 to double-blind ARI (10 to 30 mg/day) or placebo (PBO) plus LI or VAL. Relapse was monitored up to 52 weeks.
337 subjects were randomised to continuation of mood stabiliser plus adjunctive ARI or PBO; 61.3% and 52.7%, respectively, completed the study. Adjunctive ARI significantly delayed the time to any relapse, hazard ratio = 0.544 (95% CI: 0.33, 0.89, log-rank p = 0.014). Overall relapse rates at 52 weeks were 14.9% and 25.4% in ARI vs PBO subjects. A superior reduction in CGI-BP Mania Severity of Illness from baseline at 52 weeks was also observed (0.3 vs. 0.0, respectively, p = 0.01). Adverse events generally were as expected per known drug and illness profiles with no significant difference in mean change in body weight between adjunctive PBO (0.60 kg) and adjunctive ARI (1.07 kg) (p = 0.49 Week 52, LOCF).
Continuation of aripiprazole treatment increased time to relapse to any mood episode compared with placebo plus LI/VAL over 1 year, indicating a long-term benefit in continuing adjunctive aripiprazole to a mood stabiliser after sustained remission is achieved.
Congenital renal and urinary tract anomalies are common, accounting for up to 21% of all congenital abnormalities . The reported incidence is approximately 1:250–1:1000 pregnancies  and the routine use of prenatal ultrasonography allows relatively early detection, particularly for the obstructive uropathies, which account for the majority. According to the latest UK renal registry report in 2015, ‘obstructive uropathy’ was the second leading cause (19%) of chronic renal failure in children under 16 years of age after renal dysplasia +/− reflux . The obstructions may occur within the upper or lower urinary tract, and their prognosis varies significantly, with obstructions at the level of the bladder neck being associated with the majority of neonatal mortality and renal failure. In untreated cases, perinatal mortality is high (up to 45%, often because of associated severe oligohydramnios and pulmonary hypoplasia) , and 30% of the survivors suffer from end-stage renal failure (ESRF) requiring dialysis and renal transplantation before the age of 5 . The overall chance of survival in childhood is lowest if renal support therapy or transplantation is commenced before 2 years old when compared with starting at 12–16 years old (hazard ratio [HR] of 4.1, 95% confidence interval [CI] 1.7–9.9, P = 0.002) . Therefore, in utero intervention, by the insertion of a vesicoamniotic shunt, or therapeutic treatment by fetal cystoscopy and valvular ablation, has been attempted to attenuate in utero progression of these pathologies (and their consequences) and to alter the natural history of congenital bladder neck obstruction in childhood. In this chapter, we discuss the etiology, pathophysiology, prenatal presentation and diagnosis of congenital bladder neck obstruction. Suggested algorithms for screening and the prenatal prognostic evaluation in selecting candidates for in utero therapy will be discussed.
Indigenous women and children experience some of the most profound health disparities globally. These disparities are grounded in historical and contemporary trauma secondary to colonial atrocities perpetuated by settler society. The health disparities that exist for chronic diseases may have their origins in early-life exposures that Indigenous women and children face. Mechanistically, there is evidence that these adverse exposures epigenetically modify genes associated with cardiometabolic disease risk. Interventions designed to support a resilient pregnancy and first 1000 days of life should abrogate disparities in early-life socioeconomic status. Breastfeeding, prenatal care and early child education are key targets for governments and health care providers to start addressing current health disparities in cardiometabolic diseases among Indigenous youth. Programmes grounded in cultural safety and co-developed with communities have successfully reduced health disparities. More works of this kind are needed to reduce inequities in cardiometabolic diseases among Indigenous women and children worldwide.
Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88) presented a critique of our recently published paper in Cell Reports entitled ‘Large-Scale Cognitive GWAS Meta-Analysis Reveals Tissue-Specific Neural Expression and Potential Nootropic Drug Targets’ (Lam et al., Cell Reports, Vol. 21, 2017, 2597–2613). Specifically, Hill offered several interrelated comments suggesting potential problems with our use of a new analytic method called Multi-Trait Analysis of GWAS (MTAG) (Turley et al., Nature Genetics, Vol. 50, 2018, 229–237). In this brief article, we respond to each of these concerns. Using empirical data, we conclude that our MTAG results do not suffer from ‘inflation in the FDR [false discovery rate]’, as suggested by Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88), and are not ‘more relevant to the genetic contributions to education than they are to the genetic contributions to intelligence’.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
For the first time, valence electron energy-loss spectroscopy (VEELS) was applied to individual single-crystalline SnO2 nanowires to investigate the dielectric function, band gap, and optical absorption coefficient. The results are compared with data from optical techniques such as spectroscopic ellipsometry and UV-Vis, and theoretical calculations from variations of density functional theory. The data obtained agree well with the standard optical and theoretical techniques. The dielectric function and optical absorption coefficient are given up to 20 eV, which otherwise requires a synchrotron source and large single crystals via optical methods. The energy loss function is given up to 40 eV, which gives a useful comparison to previous theoretical studies in an energy range that cannot be achieved via optical measurements. The comparison gives confidence in the accuracy of this method for exploring spatially-resolved measurements in individual nanoparticles or more complex nanostructures that are otherwise difficult to measure accurately using optical techniques.
A K-band (18-25 GHz) reflected-wave ruby maser (Moore and Clauss 1979) has been borrowed from the National Radio Astronomy Observatory for radio astronomy use on the NASA 64-m antenna of the Deep Space Network at the Tidbinbilla Tracking Station, near Canberra. The purpose of the installation is to provide additional sensitive spectral line, continuum, and VLBI capabilities in the southern hemisphere. Previous measurements at 22.3 GHz (λ = 13.5 mm) determined that the Tidbinbilla 64-m antenna has a peak aperture efficiency of ˜22%, a well-behaved beam shape and consistent pointing (Fourikis and Jauncey 1979). Before installing the maser on the antenna a cooled (circulator) switch was added to provide a beam-switching capability, and a spectral line receiver following the maser was incorporated. The system was assembled and tested at JPL in late 1980 and installed at Tidbinbilla early in 1981. We give here a brief description and present some of the first line observations made in February and March 1981. Extensive line and continuum observations are planned with the present system and a program is under way to determine the telescope pointing characteristics.
Iodine-129 is a high-yield fission product formed in nuclear reactors and is a risk-driving radionuclide in both contaminated land and radioactive waste disposal due to its high mobility and long half-life. Here, the bioreduction behaviour of iodate was investigated by tracking iodine speciation and concentration in solution during the development of progressive anoxia in sediment microcosm experiments incubated at neutral pH. Experiments with acetate added as an electron donor showed the expected cascade of terminal electron-accepting processes. Analysis of solution chemistry showed reduction of iodate to iodide during the early stages of metal (Mn(IV) and Fe(III)) reduction, but with no significant retention of iodine species on solids. There was, however, a net release of natural iodine associated with the sediments to solution when robust iron reduction / sulfate reduction had developed. In addition, over 210 days, the controls with no electron donor and the sterile controls showed no Mn(IV) or Fe(III) reduction but displayed modest sorption of iodate to the sediments in the absence of bioreduction. Overall these results show that under oxic conditions iodate may be partially sorbed to sediments over extended periods but that development of mildly reducing conditions leads to the reductive release of iodine to solution as iodide.
We present the first quantitative assessment of combustion dynamics of on-chip porous silicon (PS) energetic material using sulfur and nitrate-based oxidizers with potential for improved moisture stability and/or minimized environmental impact compared to sodium perchlorate (NaClO4). Material properties of the PS films were characterized using gas adsorption porosimetry, and profilometry to calculate specific surface area, porosity and etch depth. The PS/sulfur energetic composite was formed using three pore loading techniques, where the combustion speeds ranged from 2.9 – 290 m/s. The nitrate-based oxidizers were solution-deposited using different compatible solvents, and depending on the metal-nitrate yielded combustion speeds of 3.1 – 21 m/s. Additionally, the combustion enthalpies from bomb calorimetry experiments are reported for the alternative PS/oxidizer systems in both nitrogen and oxygen environments.
Iron oxides resulting from the corrosion of large quantities of steel that are planned to be installed throughout a deep geological disposal facility (GDF) are expected to be one of the key surfaces of interest for controlling radionuclide behaviour under disposal conditions. Over the lengthy timescales associated with a GDF, the system is expected to become anoxic so that reduced Fe(II) phases will dominate. Batch experiments have therefore been completed in order to investigate how a model reduced Fe-oxide surface (wüstite, Fe1–xO) alters as a function of exposure to aqueous solutions with compositions representative of conditions expected within a GDF. Additional experiments were performed to constrain the effect that highly alkaline solutions (up to pH 13) have on the adsorption behaviour of the uranyl (UO22+) ion onto the surfaces of both wüstite and portlandite [Ca(OH)2; representative of the expected cementitious phases]. Surface co-ordination chemistry and speciation were determined by ex situ X-ray absorption spectroscopy measurements (both X-ray absorption near-edge structure analysis (XANES) and extended X-ray absorption fine structure analysis (EXAFS)). Diffraction, elemental analysis and XANES showed that the bulk solid composition and Fe oxidation state remained relatively unaltered over the time frame of these experiments (120 h), although under alkaline conditions possible surface hydroxylation is observed, due presumably to the formation of surface hydroxyl complexes. The surface morphology, however, is altered significantly with a large degree of roughening and an observed decrease in the average particle size. Reduction of U(VI) to U(IV) occurs during adsorption in almost all cases and this is interpreted to indicate that wüstite may be an effective reductant of U during surface adsorption. This work also shows that increasing the carbonate concentration in reactant solutions dramatically decreases the adsorption coefficients for U on both wüstite and portlandite, consistent with U speciation and surface reactivity determined in other studies. Finally, the EXAFS results include new details about exactly how U bonds to this metal oxide surface.
Based on our deep image of Sgr A using broadband data observed with the VLA† at 6 cm, we present a new perspective of the radio bright zone at the Galactic center. We further show the radio detection of the X-ray Cannonball, a candidate neutron star associated with the Galactic center SNR Sgr A East. The radio image is compared with the Chandra X-ray image to show the detailed structure of the radio counterparts of the bipolar X-ray lobes. The bipolar lobes are likely produced by the winds from the activities within Sgr A West, which could be collimated by the inertia of gas in the CND, or by the momentum driving of Sgr A*; and the poloidal magnetic fields likely play an important role in the collimation. The less-collimated SE lobe, in comparison to the NW one, is perhaps due to the fact that the Sgr A East SN might have locally reconfigured the magnetic field toward negative galactic latitudes. In agreement with the X-ray observations, the time-scale of ∼1 × 104 yr estimated for the outermost radio ring appears to be comparable to the inferred age of the Sgr A East SNR.
Deep imaging of the Sgr A complex at 6 cm wavelength with the B and C configurations of the Karl G. Jansky VLA† has revealed a new population of faint radio filaments. Like their brighter counterparts that have been observed throughout the Galactic center on larger scales, these filaments can extend up to ∼10 parsecs, and in most cases are strikingly uniform in brightness and curvature. Comparison with a survey of Paschen-α emission reveals that some of the filaments are emitting thermally, but most of these structures are nonthermal: local magnetic flux tubes illuminated by synchrotron emission. The new image reveals considerable filamentary substructure in previously known nonthermal filaments (NTFs). Unlike NTFs previously observed on larger scales, which tend to show a predominant orientation roughly perpendicular to the Galactic plane, the NTFs in the vicinity of the Sgr A complex are relatively randomly oriented. Two well-known radio sources to the south of Sgr A – sources E and F – consist of numerous quasi-parallel filaments that now appear to be particularly bright portions of a much larger, strongly curved, continuous, nonthermal radio structure that we refer to as the “Southern Curl”. It is therefore unlikely that sources E and F are Hii regions or pulsar wind nebulae. The Southern Curl has a smaller counterpart on the opposite side of the Galactic center – the Northern Curl – that, except for its smaller scale and smaller distance from the center, is roughly point-reflection symmetric with respect to the Southern Curl. The curl features indicate that some field lines are strongly distorted, presumably by mass flows. The point symmetry about the center then suggests that the flows originate near the center and are somewhat collimated.
Polarimetry of the far infrared emission from magnetically-aligned interstellar grains is one of the best ways of studying the magnetic field at the Galactic center. We describe the HAWC+ instrument, under development for flight on SOFIA starting in 2015, which will provide a major advance in capability for these critically important measurements.
The electrical heating of Ni/Al laminate foils allows interrogation of phenomena at heating rates as high as 10^12 K/s. In the 2011 Fall MRS meeting, we reported on emission spectra from rapidly heated Ni/Al laminates resolved temporally over 350 ns, which provided qualitative evidence of rapid and exothermic vapor phase mixing of Ni and Al in these experiments which we term electrical explosions. These results were significant, because thermal diffusion processes normally limit Ni/Al reactions to much slower energy release rates, potentially limiting their applications. Here we present further evidence of exothermic Ni/Al mixing, quantified by experimental velocity measurements of encapsulation material and interpreted by numerical calculations of energy partitioning into different processes. These calculations agreed well with experiments from different Al, Cu, and Ni samples, sputter-deposited and lithographically patterned into bow-tie bridge structures. Velocity measurements of up to 5 km/s for 11.5 μm thick parylene encapsulation layers were accurately predicted using a single, empirical fitting parameter which depended on the electrical circuit used. The calculations also agreed with encapsulation layers accelerated by electrically exploded Ni/Al laminates as long as an additional 1.2 kJ/g of energy was included in the model. This value is precisely the enthalpy of mixing between Ni and Al, and therefore quantifies the transduction of energy into encapsulation layer kinetic energy.
We present experimental results supporting physics-based ejecta model development, where our main assumption is that ejecta form as a special limiting case of a Richtmyer–Meshkov (RM) instability at a metal–vacuum interface. From this assumption, we test established theory of unstable spike and bubble growth rates, rates that link to the wavelength and amplitudes of surface perturbations. We evaluate the rate theory through novel application of modern laser Doppler velocimetry (LDV) techniques, where we coincidentally measure bubble and spike velocities from explosively shocked solid and liquid metals with a single LDV probe. We also explore the relationship of ejecta formation from a solid material to the plastic flow stress it experiences at high-strain rates () and high strains (700 %) as the fundamental link to the onset of ejecta formation. Our experimental observations allow us to approximate the strength of Cu at high strains and strain rates, revealing a unique diagnostic method for use at these extreme conditions.