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Natural living conductive biofilms transport electrons between electrodes and cells, as well as among cells fixed within the film, catalyzing an array of reactions from acetate oxidation to CO2 reduction. Synthetic biology offers tools to modify or improve electron transport through biofilms, creating a new class of engineered living conductive materials. Engineered living conductive materials could be used in a range of applications for which traditional conducting polymers are not appropriate, including improved catalytic coatings for microbial fuel-cell electrodes, self-powered sensors for austere environments, and next-generation living components of bioelectronic devices that interact with the human microbiome.
Understanding predictors of successful ageing is essential to policy development promoting quality-of-life of an ageing population. Initial models precluded successful ageing in the presence of chronic disease/functional disability; however, this is discrepant with self-reported successful ageing. Indicators of social, psychological and physical health in 1,735 people aged 65–74, living in Canada, Columbia, Brazil or Albania, were analysed in the International Mobility in Ageing Study. Multiple logistic regression analysis was performed to estimate the change in self-rated successful ageing in relation to physical health, depression, social connectedness, resilience and site, while controlling for age, gender and income sufficiency. Sixty-five per cent of participants self-rated as ageing successfully; however, this was significantly different across sites (p < 0.0005, range 17–85%) and gender (p = 0.019). Using objective measures, 6 per cent were classified as ‘successful’, with significant variability amongst sites (p < 0.0005, range 0–12%). Subjective successful ageing was associated with fewer (not absence of) chronic diseases, absence of depression and less dysfunction in activities of daily living, but not with objective measures of physical dysfunction. Social connectedness and resilience also aligned with self-rated successful ageing. Traditional definitions of objective successful ageing are likely too restrictive, and thus, do not approximate self-rated successful ageing. International differences suggest that site could be a surrogate for variables other than physical/mental health and social engagement.
This study evaluates the morbidity, mortality, and cost differences between patients who underwent either a simple or a complex arterial switch operation.
A retrospective study of patients undergoing an arterial switch operation at a single institution was performed. Simple cases were defined as patients with d-transposition of the great arteries with usual coronary anatomy or circumflex artery originating from the right with either intact ventricular septum or ventricular septal defect. Complex cases included all other forms of coronary anatomy, aortic coarctation or arch hypoplasia, and Taussig–Bing anomalies. Costs were acquired using an institutional activity-based accounting system.
A total of 98 patients were identified, 68 patients in the simple group and 30 in the complex group. The mortality rate was 2% for the simple and 7% for the complex group, p=0.23. Major morbidities including cardiac arrest, extracorporeal membrane oxygenation, a major coronary event, surgical or catheter-based re-intervention, stroke, or permanent pacemaker placement, non-cardiac surgical procedures, mediastinitis, and sepsis did not differ between the simple and complex groups (16 versus 27%, p=0.16). The complex group had increased bleeding requiring re-exploration (0 versus 10%, p=0.04). Hospital and ICU length of stay did not differ. Complex patients had higher overall hospital costs (simple $80,749 versus complex $97,387, p=0.01) and higher postoperative costs (simple $60,192 versus complex $70,132, p=0.02). The operating room and supplies accounted for the majority of the cost difference.
Complex arterial switches can be safely performed with low rates of morbidity and mortality but at an increased cost.
We present results from a multiwavelength study of the blazar PKS 1954–388 at radio, UV, X-ray, and gamma-ray energies. A RadioAstron observation at 1.66 GHz in June 2012 resulted in the detection of interferometric fringes on baselines of 6.2 Earth-diameters. This suggests a source frame brightness temperature of greater than 2 × 1012 K, well in excess of both equipartition and inverse Compton limits and implying the existence of Doppler boosting in the core. An 8.4-GHz TANAMI VLBI image, made less than a month after the RadioAstron observations, is consistent with a previously reported superluminal motion for a jet component. Flux density monitoring with the Australia Telescope Compact Array confirms previous evidence for long-term variability that increases with observing frequency. A search for more rapid variability revealed no evidence for significant day-scale flux density variation. The ATCA light-curve reveals a strong radio flare beginning in late 2013, which peaks higher, and earlier, at higher frequencies. Comparison with the Fermi gamma-ray light-curve indicates this followed ~ 9 months after the start of a prolonged gamma-ray high-state—a radio lag comparable to that seen in other blazars. The multiwavelength data are combined to derive a Spectral Energy Distribution, which is fitted by a one-zone synchrotron-self-Compton (SSC) model with the addition of external Compton (EC) emission.
We investigated the physiology of two closely related albatross species relative to their breeding strategy: black-browed albatrosses (Thalassarche melanophris) breed annually, while grey-headed albatrosses (T. chrysostoma) breed biennially. From observations of breeding fate and blood samples collected at the end of breeding in one season and feather corticosterone levels (fCort) sampled at the beginning of the next breeding season, we found that in both species some post-breeding physiological parameters differed according to breeding outcome (successful, failed, deferred). Correlations between post-breeding physiology and fCort, and links to future breeding decisions, were examined. In black-browed albatrosses, post-breeding physiology and fCort were not significantly correlated, but fCort independently predicted breeding decision the next year, which we interpret as a possible migratory carry-over effect. In grey-headed albatrosses, post-breeding triglyceride levels were negatively correlated with fCort, but only in females, which we interpret as a potential cost of reproduction. However, this potential cost did not carry-over to future breeding in the grey-headed albatrosses. None of the variables predicted future breeding decisions. We suggest that biennial breeding in the grey-headed albatrosses may have evolved as a strategy to buffer against the apparent susceptibility of females to negative physiological costs of reproduction. Future studies are needed to confirm this.
We gathered a multiwavelength dataset of two well-known LBVs. We found a complex mass-loss, with evidence of variability, such as has been seen previously. In addition, our data reveal signatures of collimated stellar winds. We propose a new scenario for these two stars where the nebula shaping is influenced by the presence of a companion star and/or fast rotation.
Radiocarbon is produced within minerals at the earth's surface (in situ production) by a number of spallation reactions. Its relatively short half-life of 5730 yr provides us with a unique cosmogenic nuclide tool for the measurement of rapid erosion rates (>10−3 cm yr−1) and events occurring over the past 25 kyr. At SUERC, we have designed and built a vacuum system to extract 14C from quartz which is based on a system developed at the University of Arizona. This system uses resistance heating of samples to a temperature of approximately 1100° in the presence of lithium metaborate (LiBO2) to dissolve the quartz and liberate any carbon present. During extraction, the carbon is oxidized to CO2 in an O2 atmosphere so that it may be collected cryogenically. The CO2 is subsequently purified and converted to graphite for accelerator mass spectrometry (AMS) measurement. One of the biggest problems in measuring in situ 14C is establishing a low and reproducible system blank and efficient extraction of the in situ 14C component. Here, we present initial data for 14C-free CO2, derived from geological carbonate and added to the vacuum system to determine the system blank. Shielded quartz samples (which should be 14C free) and a surface quartz sample routinely analyzed at the University of Arizona were also analyzed at SUERC, and the data compared with values derived from the University of Arizona system.
We provide detailed contextual information on 25 14C dates for unusually well-preserved archaeological and paleontological remains from Daisy Cave. Paleontological materials, including faunal and floral remains, have been recovered from deposits spanning roughly the past 16,000 yr, while archaeological materials date back to ca. 10,500 BP. Multidisciplinary investigations at the site provide a detailed record of environmental and cultural changes on San Miguel Island during this time period. This record includes evidence for the local or regional extinction of a number of animal species, as well as some of the earliest evidence for the human use of boats and other maritime activities in the Americas. Data from Daisy Cave contribute to a growing body of evidence that Paleoindians had adapted to a wide variety of New World environments prior to 10,000 PB. Analysis of shell-charcoal pairs, along with isotopic analysis of associated marine shells, supports the general validity of marine shell dating, but also provides evidence for temporal fluctuations in the reservoir effect within the Santa Barbara Channel region.
We present the strategy and status of a gravitational lens search for multiple imaging with angular separations between 6″ and 15″ within the combined JVAS and CLASS dataset of ˜ 15000 flat-spectrum radio sources. Currently all but one lens candidate have been rejected.
With HST and WFPC2, galaxies in the Medium Deep Survey can be reliably classified to magnitudes I814 ≲ 22.0 in the F814W band, at a mean redshift . The main result is the relatively high proportion (~40%) of objects which are in some way irregular or anomalous, and which are of relevance in understanding the origin of the familiar excess population of faint galaxies. These diverse objects include compact galaxies, apparently interacting pairs, galaxies with superluminous starforming regions and diffuse low surface brightness galaxies of various forms. The ‘irregulars’ and ‘peculiar’ galaxies contribute most of the excess counts in the I-band at our limiting magnitude, and may explain the ‘faint blue galaxy’ problem.
Work on the development and use of optical fibres as light guides in astronomical spectroscopy has been underway at the AAO for over a year now. The fibres used are step-index polymer-clad silica with a core size of 200 microns giving an aperture size of 1.3 arcsec at the AAT f/8 focus. They are optimised for data transmission with losses below 5dB/km at a wavelength of 800 nm. The blue transmission is somewhat lower, typically 500dB/km at 300nm and 90dB/km at 400nm but over the short 2m length used these attenuations give transmissions of 79% and 96% respectively.
PKS 1830–211 is the strongest known radio gravitational lens by almost an order of magnitude and has the potential to provide a measurement of H0, provided the lensing system can be parameterized. Attempts to identify optical counterparts, to measure redshifts, have so far proved unsuccessful and this has lead to radio and millimetre spectral line observations. We present our discovery of an absorption system at z = 0.19. A brief description is also made of our ATCA observations to measure the lensing time delay for this source.
Astronomical telescopes continue to demand high-endurance high-reflectivity silver mirrors that can withstand years of exposure in earth-based observatory environments. The University of California Observatories Astronomical Coatings Lab has undertaken development of protected silver coatings suitable for telescope mirrors that maintain high reflectivity at wavelengths from 340 nm through the mid-infrared spectrum. We present promising results of enhanced corrosion barriers using plasma-enhanced atomic layer deposition (PEALD) of aluminum oxide (AlOx) as a top barrier layer. Novel coating recipes developed with ion-assisted electron beam deposition (IAEBD) of materials including yttrium fluoride and oxides of yttrium, tantalum, and silicon are used to compare the endurance of physical vapor deposition-grown barriers with PEALD-grown barriers of similar thickness. Samples of these mirror coatings were covered with conformal layers of AlOx deposited by PEALD using trimethylaluminum as a metal precursor and plasma-activated oxygen as an oxidant gas. Samples of coating recipes with and without PEALD oxide undergo aggressive high temperature/high humidity (HTHH) environmental testing in which samples are exposed to an environment of 80% humidity at 80°C for ten days in a simple test set-up. HTHH testing show visible results suggesting that the PEALD oxide offers enhanced robust protection against chemical corrosion and moisture from an accelerated aging environment. Mirror samples are further characterized by reflectivity/absorption before and after deposition of oxide coatings. AlOx is suitable for many applications and has been the initial material choice for this study.
A symptom of mild cognitive impairment (MCI) and Alzheimer’s disease
(AD) is a flat learning profile. Learning slope calculation methods vary, and
the optimal method for capturing neuroanatomical changes associated with MCI and
early AD pathology is unclear. This study cross-sectionally compared four
different learning slope measures from the Rey Auditory Verbal Learning Test
(simple slope, regression-based slope, two-slope method, peak slope) to
structural neuroimaging markers of early AD neurodegeneration (hippocampal
volume, cortical thickness in parahippocampal gyrus, precuneus, and lateral
prefrontal cortex) across the cognitive aging spectrum [normal
control (NC); (n=198;
age=76±5), MCI (n=370;
age=75±7), and AD (n=171;
age=76±7)] in ADNI. Within diagnostic group,
general linear models related slope methods individually to neuroimaging
variables, adjusting for age, sex, education, and APOE4 status. Among MCI,
better learning performance on simple slope, regression-based slope, and late
slope (Trial 2–5) from the two-slope method related to larger
parahippocampal thickness (all p-values<.01) and
hippocampal volume (p<.01). Better regression-based
slope (p<.01) and late slope
(p<.01) were related to larger ventrolateral
prefrontal cortex in MCI. No significant associations emerged between any slope
and neuroimaging variables for NC (p-values ≥.05) or
AD (p-values ≥.02). Better learning performances
related to larger medial temporal lobe (i.e., hippocampal volume,
parahippocampal gyrus thickness) and ventrolateral prefrontal cortex in MCI
only. Regression-based and late slope were most highly correlated with
neuroimaging markers and explained more variance above and beyond other common
memory indices, such as total learning. Simple slope may offer an acceptable
alternative given its ease of calculation. (JINS, 2015,
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Streams draining the Cypress Hills support unique and understudied macroinvertebrate communities in Saskatchewan, Canada. Here, we report the discovery of a species of caddisfly new to the Cypress Hills and Saskatchewan, Neophylax splendens Denning (Trichoptera: Thremmatidae). Larvae were collected early in May 2012, and are found to enter pre-pupal diapause in mid-June until mid-September. Larvae were identified as N. splendens by morphological characters and verified with genetic analysis. Its occurrence strengthens the biogeographical link between the montane regions in British Columbia, Canada and Utah, United States of America with the southwest corner of Saskatchewan. This study highlights the importance of seasonal sampling, resolute species level identifications in biological surveys and the use of genetic analyses to obtain this level of identification.
An overview of the Czech national R&D project HiLASE (High average power pulsed laser) is presented. The project focuses on the development of advanced high repetition rate, diode pumped solid state laser (DPSSL) systems with energies in the range from mJ to 100 J and repetition rates in the range from 10 Hz to 100 kHz. Some applications of these lasers in research and hi-tech industry are also presented.