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The Subglacial Antarctic Lakes Scientific Access (SALSA) Project accessed Mercer Subglacial Lake using environmentally clean hot-water drilling to examine interactions among ice, water, sediment, rock, microbes and carbon reservoirs within the lake water column and underlying sediments. A ~0.4 m diameter borehole was melted through 1087 m of ice and maintained over ~10 days, allowing observation of ice properties and collection of water and sediment with various tools. Over this period, SALSA collected: 60 L of lake water and 10 L of deep borehole water; microbes >0.2 μm in diameter from in situ filtration of ~100 L of lake water; 10 multicores 0.32–0.49 m long; 1.0 and 1.76 m long gravity cores; three conductivity–temperature–depth profiles of borehole and lake water; five discrete depth current meter measurements in the lake and images of ice, the lake water–ice interface and lake sediments. Temperature and conductivity data showed the hydrodynamic character of water mixing between the borehole and lake after entry. Models simulating melting of the ~6 m thick basal accreted ice layer imply that debris fall-out through the ~15 m water column to the lake sediments from borehole melting had little effect on the stratigraphy of surficial sediment cores.
This study aimed to examine the predictors of cognitive performance in patients with pediatric mild traumatic brain injury (pmTBI) and to determine whether group differences in cognitive performance on a computerized test battery could be observed between pmTBI patients and healthy controls (HC) in the sub-acute (SA) and the early chronic (EC) phases of injury.
203 pmTBI patients recruited from emergency settings and 159 age- and sex-matched HC aged 8–18 rated their ongoing post-concussive symptoms (PCS) on the Post-Concussion Symptom Inventory and completed the Cogstate brief battery in the SA (1–11 days) phase of injury. A subset (156 pmTBI patients; 144 HC) completed testing in the EC (∼4 months) phase.
Within the SA phase, a group difference was only observed for the visual learning task (One-Card Learning), with pmTBI patients being less accurate relative to HC. Follow-up analyses indicated higher ongoing PCS and higher 5P clinical risk scores were significant predictors of lower One-Card Learning accuracy within SA phase, while premorbid variables (estimates of intellectual functioning, parental education, and presence of learning disabilities or attention-deficit/hyperactivity disorder) were not.
The absence of group differences at EC phase is supportive of cognitive recovery by 4 months post-injury. While the severity of ongoing PCS and the 5P score were better overall predictors of cognitive performance on the Cogstate at SA relative to premorbid variables, the full regression model explained only 4.1% of the variance, highlighting the need for future work on predictors of cognitive outcomes.
Cognitive behavior therapy (CBT) is effective for most patients with a social anxiety disorder (SAD) but a substantial proportion fails to remit. Experimental and clinical research suggests that enhancing CBT using imagery-based techniques could improve outcomes. It was hypothesized that imagery-enhanced CBT (IE-CBT) would be superior to verbally-based CBT (VB-CBT) on pre-registered outcomes.
A randomized controlled trial of IE-CBT v. VB-CBT for social anxiety was completed in a community mental health clinic setting. Participants were randomized to IE (n = 53) or VB (n = 54) CBT, with 1-month (primary end point) and 6-month follow-up assessments. Participants completed 12, 2-hour, weekly sessions of IE-CBT or VB-CBT plus 1-month follow-up.
Intention to treat analyses showed very large within-treatment effect sizes on the social interaction anxiety at all time points (ds = 2.09–2.62), with no between-treatment differences on this outcome or clinician-rated severity [1-month OR = 1.45 (0.45, 4.62), p = 0.53; 6-month OR = 1.31 (0.42, 4.08), p = 0.65], SAD remission (1-month: IE = 61.04%, VB = 55.09%, p = 0.59); 6-month: IE = 58.73%, VB = 61.89%, p = 0.77), or secondary outcomes. Three adverse events were noted (substance abuse, n = 1 in IE-CBT; temporary increase in suicide risk, n = 1 in each condition, with one being withdrawn at 1-month follow-up).
Group IE-CBT and VB-CBT were safe and there were no significant differences in outcomes. Both treatments were associated with very large within-group effect sizes and the majority of patients remitted following treatment.
We developed a tilt sensor for studying ice deformation and installed our tilt sensor systems in two boreholes drilled close to the shear margin of Jarvis Glacier, Alaska to obtain kinematic measurements of streaming ice. We used the collected tilt data to calculate borehole deformation by tracking the orientation of the sensors over time. The sensors' tilts generally trended down-glacier, with an element of cross-glacier flow in the borehole closer to the shear margin. We also evaluated our results against flow dynamic parameters derived from Glen's exponential flow law and explored the parameter space of the stress exponent n and enhancement factor E. Comparison with values from ice deformation experiments shows that the ice on Jarvis is characterized by higher n values than that is expected in regions of low stress, particularly at the shear margin (~3.4). The higher n values could be attributed to the observed high total strains coupled with potential dynamic recrystallization, causing anisotropic development and consequently sped up ice flow. Jarvis' n values place the creep regime of the ice between basal slip and dislocation creep. Tuning E towards a theoretical upper limit of 10 for anisotropic ice with single-maximum fabric reduces the n values by 0.2.
The deep subsurface of other planetary bodies is of special interest for robotic and human exploration. The subsurface provides access to planetary interior processes, thus yielding insights into planetary formation and evolution. On Mars, the subsurface might harbour the most habitable conditions. In the context of human exploration, the subsurface can provide refugia for habitation from extreme surface conditions. We describe the fifth Mine Analogue Research (MINAR 5) programme at 1 km depth in the Boulby Mine, UK in collaboration with Spaceward Bound NASA and the Kalam Centre, India, to test instruments and methods for the robotic and human exploration of deep environments on the Moon and Mars. The geological context in Permian evaporites provides an analogue to evaporitic materials on other planetary bodies such as Mars. A wide range of sample acquisition instruments (NASA drills, Small Planetary Impulse Tool (SPLIT) robotic hammer, universal sampling bags), analytical instruments (Raman spectroscopy, Close-Up Imager, Minion DNA sequencing technology, methane stable isotope analysis, biomolecule and metabolic life detection instruments) and environmental monitoring equipment (passive air particle sampler, particle detectors and environmental monitoring equipment) was deployed in an integrated campaign. Investigations included studying the geochemical signatures of chloride and sulphate evaporitic minerals, testing methods for life detection and planetary protection around human-tended operations, and investigations on the radiation environment of the deep subsurface. The MINAR analogue activity occurs in an active mine, showing how the development of space exploration technology can be used to contribute to addressing immediate Earth-based challenges. During the campaign, in collaboration with European Space Agency (ESA), MINAR was used for astronaut familiarization with future exploration tools and techniques. The campaign was used to develop primary and secondary school and primary to secondary transition curriculum materials on-site during the campaign which was focused on a classroom extra vehicular activity simulation.
The goal of the Materials Genome Initiative is to substantially reduce the time and cost of materials design and deployment. Achieving this goal requires taking advantage of the recent advances in data and information sciences. This critical need has impelled the emergence of a new discipline, called materials data science and informatics. This emerging new discipline not only has to address the core scientific/technological challenges related to datafication of materials science and engineering, but also, a number of equally important challenges around data-driven transformation of the current culture, practices, and workflows employed for materials innovation. A comprehensive effort that addresses both of these aspects in a synergistic manner is likely to succeed in realizing the vision of scaled-up materials innovation. Key toolsets needed for the successful adoption of materials data science and informatics in materials innovation are identified and discussed in this article. Prototypical examples of emerging novel toolsets and their functionality are described along with select case studies.
Background: The diagnosis of a sports-related concussion is often dependent on the athlete self-reporting their symptoms. It has been suggested that improving youth athlete knowledge and attitudes toward concussion may increase self-reporting behaviour. The objective of this study was to determine if a novel Concussion-U educational program improves knowledge of and attitudes about concussion among a cohort of elite male Bantam and Midget AAA hockey players. Methods: Fifty-seven male Bantam and Midget AAA-level hockey players (mean age=14.52±1.13 years) were recruited from the local community. Each participant completed a modified version of the Rosenbaum Concussion Knowledge and Attitudes Survey–Student Version immediately before and after a Concussion-U educational presentation. Follow-up sessions were arranged 4 to 6 months after the presentation, and assessed retention of knowledge and attitude changes. Results: Forty-three players completed all three surveys. Concussion knowledge and attitude scores significantly (p<0.01) increased from pre- to post-presentation by 12.79 and 8.41%, respectively. At long-term follow-up, knowledge levels remained significantly (p<0.01) higher than baseline by 8.49%. Mean attitude scores were also increased at follow-up; however, this increase was not statistically significant. Conclusions: A Concussion-U educational program led to an immediate improvement in concussion knowledge and attitudes among elite male Bantam and Midget AAA hockey players. Increased knowledge was maintained at long-term follow-up, but improved attitude was not. Future studies should investigate whether similar educational programs influence symptom reporting and concussion incidence. In addition, they should focus on how to maintain improved concussion attitudes.
To determine the effect of interhospital patient sharing via transfers on the rate of Clostridium difficile infections in a hospital.
Using data from the Healthcare Cost and Utilization Project California State Inpatient Database, 2005–2011, we identified 2,752,639 transfers. We then constructed a series of networks detailing the connections formed by hospitals. We computed 2 measures of connectivity, indegree and weighted indegree, measuring the number of hospitals from which transfers into a hospital arrive, and the total number of incoming transfers, respectively. Next, we estimated a multivariate model of C. difficile infection cases using the log-transformed network measures as well as covariates for hospital fixed effects, log median length of stay, log fraction of patients aged 65 or older, and quarter and year indicators as predictors.
We found an increase of 1 in the log indegree was associated with a 4.8% increase in incidence of C. difficile infection (95% CI, 2.3%–7.4%) and an increase of 1 in log weighted indegree was associated with a 3.3% increase in C. difficile infection incidence (1.5%–5.2%). Moreover, including measures of connectivity in our models greatly improved their fit.
Our results suggest infection control is not under the exclusive control of a given hospital but is also influenced by the connections and number of connections that hospitals have with other hospitals.
Infect. Control Hosp. Epidemiol. 2015;36(9):1031–1037
Electron microscopy (EM), cryo-electron microscopy (cryo-EM), and cryo-electron tomography (cryo-ET) are essential techniques used for characterizing basic virus morphology and determining the three-dimensional structure of viruses. Enveloped viruses, which contain an outer lipoprotein coat, constitute the largest group of pathogenic viruses to humans. The purification of enveloped viruses from cell culture presents certain challenges. Specifically, the inclusion of host-membrane-derived vesicles, the complete destruction of the viruses, and the disruption of the internal architecture of individual virus particles. Here, we present a strategy for capturing enveloped viruses on affinity grids (AG) for use in both conventional EM and cryo-EM/ET applications. We examined the utility of AG for the selective capture of human immunodeficiency virus virus-like particles, influenza A, and measles virus. We applied nickel-nitrilotriacetic acid lipid layers in combination with molecular adaptors to selectively adhere the viruses to the AG surface. This further development of the AG method may prove essential for the gentle and selective purification of enveloped viruses directly onto EM grids for ultrastructural analyses.
In vivo efficacies of 2 alcohol-based hand rub (ABHR) products (gel and foam) were evaluated at a volume of 1.1 mL. Both met US Food and Drug Administration log10 reduction requirements after a single application and 10 consecutive applications. This is the first study to identify ABHR formulations capable of meeting efficacy requirements with a single-dispenser actuation.
As it was originally proposed, the extended phenotype comprised ‘all effects of a gene upon the world’ (Dawkins, 1989) and portrayed how the effects of a gene borne by an organism influenced its biotic and abiotic environments. The consideration of indirect genetic effects, in which an organism’s phenotype becomes part of the selective environment of conspecifics (Wolf et al., 1998), was developed rigorously in the population genetics context and the concept subsequently extended to include effects on heterospecifics (Whitham et al., 2003). The extended phenotype concept has been adopted as a framework by some evolutionary biologists and ecologists to study the roles of plant secondary metabolites (PSMs) since Whitham et al. (2003) used heritable variation in tissue tannin concentrations among Populus species and hybrids to develop the concept of community and ecosystem genetics (Antonovics, 1992).
Many studies of how genetically determined variation in plant traits, including PSMs, drive associated community phenotypes and processes, have been based on differences between hybrids (Dungey et al., 2000; Hochwender & Fritz, 2004; Bailey et al., Chapter 14). Fewer studies have investigated the effects on extended phenotypes of continuously varying PSMs or between known genotypes within a species (Whitham et al., 2006; Schweitzer et al., 2008; Barbour et al., 2009; O’Reilly-Wapstra et al., Chapter 2). A convenient approach to identification and utilisation of genotypic variation for the study of multiple effects of PSMs is provided by the use of genetic polymorphisms. A polymorphism can be defined as occurring when a trait such as a morphological or biochemical character exists in two or more distinct forms in a randomly mating population within a species (Ford, 1975). The approach is particularly useful in species that cannot be readily cloned. Here, we review examples of how intra-specific variation in a particular group of PSMs, the monoterpenes, has informed our understanding of how PSMs can play multiple ecological roles and mediate the extended phenotype of plants. The monoterpenes are a group of low-molecular-weight, volatile terpenoids which form a very diverse group in terms of number of compounds, structure and function (Gershenzon & Dudareva, 2007). We use variation within species which are polymorphic for concentrations or presence of monoterpenes to provide an insight into their ecological ramifications and larger-scale consequences, against the background of intra-specific variation in other traits.
We carried out a population-based study of dystrophin mutations in patients followed by members of the Canadian Paediatric Neuromuscular Group (CPNG) over a ten-year period.
We aimed to describe the changes in diagnostic testing for dystrophinopathy and to determine the frequency of dystrophin mutations from 2000 to 2009.
De-identified data containing the clinical phenotypes, diagnostic methods, and mutational reports from dystrophinopathy patients followed by CPNG centres from January 2000 to December 2009 were analyzed using descriptive statistics.
773 patients had a confirmed diagnosis of dystrophinopathy based on genetic testing (97%), muscle biopsy (2%), or family history (1%). 573 (74%) had complete deletion/duplication analysis of all 79 exons or whole gene sequencing, resulting in 366 (64%) deletions, 64 (11%) duplications, and 143 (25%) point mutations. The percentage of patients who were diagnosed using currently accepted genetic testing methods varied across Canada, with a mean of 63% (SD 23). 246 (43%) mutations involved exons 45 to 53. The top ten deletions (n=147, 26%) were exons 45-47, 45-48, 45, 45-50, 45-55, 51, 45-49, 45-52, 49-50, and 46-47. 169 (29%) mutations involved exons 2 to 20. The most common duplications (n=29, 5.1%) were exons 2, 2-7, 2-17, 3-7, 8-11, 10, 10-11, and 12.
This is the most comprehensive report of dystrophin mutations in Canada. Consensus guidelines regarding the diagnostic approach to dystrophinopathy will hopefully reduce the geographical variation in mutation detection rates in the coming decade.