Precision CW laser automatic tracking system investigated

Precision laser tracker capable of tracking a low acceleration target to an accuracy of about 20 microradians rms is being constructed and tested. This laser tracking has the advantage of discriminating against other optical sources and the capability of simultaneously measuring range

Fate of semi-natural grassland in England between 1960 and 2013: a test of national conservation policy

It is well documented that significant losses in semi-natural grassland occurred across Europe during the second half of the twentieth century. However, comparatively few studies have investigated and quantified the fate of large numbers of individual grassland areas. This is important for understanding the causes of decline, and consequently establishing new policies to conserve and restore lost habitats. This study addresses this problem; GIS was used to compare historic survey data collected between 1960 and 1981 with two contemporary spatial datasets of habitats in England. The datasets included the Priority Habitats Inventory 2013 and the Land Cover Map 2007 and this was undertaken for different types of semi-natural grassland across England. Considerable decreases occurred across the different grassland types, with a loss of 47% of studied semi-natural grasslands sites in England over 32–53 years. Of this, the majority of grassland was lost to conversion to agriculturally-improved grassland or arable cultivation, 45% and 43% respectively. Changes to woodland and urban areas were also evident, but on a much smaller scale. Sites receiving statutory protection as a Site of Special Scientific Interest were found to have retained more grassland (91%), compared with non-protected sites (27%), thus highlighting the effectiveness of this aspect of current conservation policy in England, and the need for this to continue in the future

Paleomagnetism of Late Jurassic Rocks in the Northern Canelo Hills, Southeastern Arizona

The Canelo Hills volcanics are exposed in the Canelo Hills, a northwest trending range in Santa Cruz County, southeast Arizona. The formation is composed of silicic tuffs and flows as well as volcaniclastic conglomerates and sandstones. Strikes of the rocks are generally to the northwest with moderate dips to the southwest and northeast. Apparent age results from the sequence studied paleomagnetically include two published isotopic dates of 147 ± 6 Ma (K-Ar, biotite) and 149 ± 11 Ma (whole rock, Rb-Sr) and a Rb/Sr isochron age, reported here, which indicates an age of 151 ± 2 Ma. Paleomagnetic samples were collected from 17 cooling units in the northern Canelo Hills. Samples from most of these units responded to alternating field (af) demagnetization, and secondary components were generally erased by peak af between 10 and 50 mT. Samples from five sites showed no response to af demagnetization. Thermal demagnetization of samples from these units produced no significant changes in direction of natural remanent magnetization (NRM), although within-site clustering of NRM directions was improved. Data from two sites were rejected because of failure to isolate a well-determined characteristic NRM. Of the remaining 15 sites, 10 sites were of normal polarity, while five sites showed reversed polarity. Intensities of the characteristic NRM ranged from 4 × 10−3 to 3 × 10−1 A/m. The data from these 15 cooling units yield a formation mean direction of I = 29.9°, D = 334.9° with k = 33.4 and α95 = 6.7°. The resulting paleomagnetic pole is at 62.2°N, 130.3° (dp = 4.1°, dm = 7.4°). This pole is between poles obtained from the Summerville and lower Morrison formations. The Canelo Hills pole is thus consistent both in position and age with the Late Jurassic episode of rapid apparent polar wander originally defined by paleomagnetic data from the Summerville and Morrison formations

Normative Feedback for Parents of College Students: Piloting a Parent Based Intervention to Correct Misperceptions of Students’ Alcohol Use and Other Parents’ Approval of Drinking

Objective Multi-component parent-based interventions (PBIs) provide a promising avenue for targeting alcohol use and related consequences in college students. Parents of college-aged children can have a significant influence on their children’s alcohol use decisions. However, parents tend to underestimate their own child’s alcohol use and overestimate other similar parents’ approval of student drinking. These misperceptions could have important implications for parents’ own attitudes and alcohol-related communication with their student. Targeting these misperceptions through normative feedback could help promote greater and more in-depth alcohol-related communication. The present study examines the potential efficacy of web-based alcohol-related normative feedback for parents of college students. Method A sample of 144 parents of college students received web-based normative feedback about students’ alcohol use and approval, as well as other same-college parents’ alcohol approval. Parents completed measures of perceived student alcohol use, student alcohol approval, other-parent alcohol approval, and intentions to discuss alcohol use both pre- and post-normative feedback. Results Post-feedback, parents reported stronger intentions to talk to their student about alcohol, were less confident in their knowledge of their students’ alcohol use, and believed that their student drank in greater quantity and more frequently than pre-feedback. Parents also perceived other parents to be less approving of alcohol use after viewing normative feedback. Conclusions These findings provide preliminary support for the use of web-based normative feedback for parents of college students. Given these promising results, further research developing and testing this approach merits attention

Event-specific risk and ecological factors associated with prepartying among heavier drinking college students

Using event-specific data, the present study sought to identify relevant risk factors and risky drinking patterns associated with prepartying. Analyses focused on drinking outcomes as a function of drinking game playing and the social context on occasions where prepartying did and did not occur. This research utilized a representative two-site sample of prepartiers who also reported a heavy episodic drinking event in the past month (n = 988). Results revealed that during a preparty event, participants drank significantly more, reached higher blood alcohol levels (BALs), and experienced significantly more negative consequences compared to the last occasion that they drank but did not preparty. Students who played drinking games when they prepartied had higher BALs and experienced more negative consequences than those who did not play drinking games. Whether females prepartied in a single-sex or coed setting had little effect on their BALs. For males, however, their BALs were greater when they prepartied in a coed setting compared to a single sex setting. Moreover, participants reported more negative consequences when they prepartied in a coed setting than in a single-sex setting. Finally, regression analyses demonstrated that participants’ BAL, frequency of prepartying, and the interaction between BAL and frequency of prepartying all uniquely contributed to the prediction of event-specific alcohol-related negative consequences. As BAL increased, the number of negative consequences increased more sharply for those who prepartied infrequently, compared to those who prepartied frequently. Analyses were examined as a function of gender which revealed important gender effects and interactions. Interventions can be designed to intervene with high-risk prepartiers by using BAL education emphasizing the impact of time-limited prepartying drinking

Psychopathology and cognitive performance in individuals with membrane-associated guanylate kinase mutations: a functional network phenotyping study.

BACKGROUND: Rare pathogenic variants in membrane-associated guanylate kinase (MAGUK) genes cause intellectual disability (ID) and have recently been associated with neuropsychiatric risk in the non-ID population. However, it is not known whether risk for psychiatric symptoms amongst individuals with ID due to MAGUK gene mutations is higher than expected for the degree of general intellectual impairment, nor whether specific cognitive differences are associated with disruption to this gene functional network. METHODS: This study addresses these two questions via behavioural questionnaires and cognitive testing, applying quantitative methods previously validated in populations with ID. We compared males with X-linked ID caused by mutations in three MAGUK genes (PAK3, DLG3, OPHN1; n = 9) to males with ID caused by mutations in other X chromosome genes (n = 17). Non-parametric and parametric analyses were applied as appropriate to data. RESULTS: Groups did not differ in age, global cognitive impairment, adaptive function or epilepsy prevalence. However, individuals with MAGUK gene mutations demonstrated significantly higher psychopathology risks, comprising elevated total problem behaviours, prominent hyperactivity and elevated scores on an autism screening checklist. Despite these overt difficulties, individuals in the MAGUK group performed more accurately than expected for age and intelligence quotient (IQ) on computerised tests of visual attention, convergent with mouse models of MAGUK loss-of-function. CONCLUSIONS: Our findings support a role for MAGUK genes in influencing cognitive parameters relevant to psychiatric risk. In addition to establishing clear patterns of impairment for this group, our findings highlight the importance of careful phenotyping after genetic diagnosis, showing that gene functional network disruptions can be associated with specific psychopathological risks and cognitive differences within the context of ID.We thank all study participants and their families for extensive contributions to this project. This study was funded by the Academy of Medical Sciences/Wellcome Trust via a Starter Grant for Clinical Lecturers to KB. KB is funded by a National Institute for Health Research Academic Clinical Lectureship. GS is funded by a Wellcome Trust project grant and a James S. McDonnell Foundation Understanding Human Cognition Scholar Award. DEA is funded by an MRC UK intramural programme (MC-A0606-5PQ41). FLR is funded by the National Institute for Health Research (Cambridge Biomedical Research Centre).This is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s11689-015-9105-

Artificial Intelligence Approach to the Determination of Physical Properties of Eclipsing Binaries. I. The EBAI Project

Achieving maximum scientific results from the overwhelming volume of astronomical data to be acquired over the next few decades will demand novel, fully automatic methods of data analysis. Artificial intelligence approaches hold great promise in contributing to this goal. Here we apply neural network learning technology to the specific domain of eclipsing binary (EB) stars, of which only some hundreds have been rigorously analyzed, but whose numbers will reach millions in a decade. Well-analyzed EBs are a prime source of astrophysical information whose growth rate is at present limited by the need for human interaction with each EB data-set, principally in determining a starting solution for subsequent rigorous analysis. We describe the artificial neural network (ANN) approach which is able to surmount this human bottleneck and permit EB-based astrophysical information to keep pace with future data rates. The ANN, following training on a sample of 33,235 model light curves, outputs a set of approximate model parameters (T2/T1, (R1+R2)/a, e sin(omega), e cos(omega), and sin i) for each input light curve data-set. The whole sample is processed in just a few seconds on a single 2GHz CPU. The obtained parameters can then be readily passed to sophisticated modeling engines. We also describe a novel method polyfit for pre-processing observational light curves before inputting their data to the ANN and present the results and analysis of testing the approach on synthetic data and on real data including fifty binaries from the Catalog and Atlas of Eclipsing Binaries (CALEB) database and 2580 light curves from OGLE survey data. [abridged]Comment: 52 pages, accepted to Ap

Genetic-Algorithm-based Light Curve Optimization Applied to Observations of the W UMa star BH Cas

I have developed a procedure utilizing a Genetic-Algorithm-based optimization scheme to fit the observed light curves of an eclipsing binary star with a model produced by the Wilson-Devinney code. The principal advantages of this approach are the global search capability and the objectivity of the final result. Although this method can be more efficient than some other comparably global search techniques, the computational requirements of the code are still considerable. I have applied this fitting procedure to my observations of the W UMa type eclipsing binary BH Cassiopeiae. An analysis of V-band CCD data obtained in 1994/95 from Steward Observatory and U- and B-band photoelectric data obtained in 1996 from McDonald Observatory provided three complete light curves to constrain the fit. In addition, radial velocity curves obtained in 1997 from McDonald Observatory provided a direct measurement of the system mass ratio to restrict the search. The results of the GA-based fit are in excellent agreement with the final orbital solution obtained with the standard differential corrections procedure in the Wilson-Devinney code.Comment: 9 pages, 2 figures, 2 tables, uses emulateapj.st