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Negative interactions between people and large carnivores are common and will probably increase as the human population and livestock production continue to expand. Livestock predation by wild carnivores can significantly affect the livelihoods of farmers, resulting in retaliatory killings and subsequent conflicts between local communities and conservationists. A better understanding of livestock predation patterns could help guide measures to improve both human relationships and coexistence with carnivores. Environmental variables can influence the intensity of livestock predation, are relatively easy to monitor, and could potentially provide a useful predictive framework for targeting mitigation. We chose lion predation of livestock as a model to test whether variations in environmental conditions trigger changes in predation. Analysing 6 years of incident reports for Pandamatenga village in Botswana, an area of high human–lion conflict, we used generalized linear models to show that significantly more attacks coincided with lower moonlight levels and temperatures, and attack severity increased significantly with extreme minimum temperatures. Furthermore, we found a delayed effect of rainfall: lower rainfall was followed by a significantly increased severity of attacks in the following month. Our results suggest that preventative measures, such as introducing deterrents or changing livestock management, could be implemented adaptively based on environmental conditions. This could be a starting point for investigating similar effects in other large carnivores, to reduce livestock attacks and work towards wider human–wildlife coexistence.
Very-long-baseline Interferometry (VLBI) has opened for study a broad new spectrum of geophysical phenomena including: direct observation of the tectonic motions and deformations of the Earth's crustal plates, observations of unprecedented detail of the variations in the rotation of the Earth, and direct measurement of the elastic deformations of the Earth in response to tidal forces. These new measurements have placed significant constraints on models of the interior structure of the Earth; for example, measurements of the variations in the Earth's nutation have been shown to be particularly sensitive to the shape of the core-mantle boundary. The VLBI measurements will allow us to construct a global reference frame accurate at the centimeter level. Such a frame will be essential to studying long-term global changes, especially those changes related to sea-level variations as recorded by tide gauge measurements.
In the application of Very-Long-Baseline Interferometry (VLBI) to astrometric problems the fundamental observable is the difference in the arrival times of a wavefront at two widely separated receiving stations. Since the radio sources being observed are sufficiently distant that the arriving wavefront can be considered to be a plane wave, the differential arrival time is a measure of the component of the baseline in the direction of the source. Equivalently, if the baseline is known, the differential arrival time is sufficient to determine a circle on the sky containing the source. It is easy to show that a minimum of ten observations distributed among three different sources is sufficient to determine all of the source coordinates and the baseline coordinates simultaneously (Robertson, 1975).
Project IRIS (International Radio Interferometric Surveying) was set up under the IAG and COSPAR to provide an operational system that would employ Very-Long-Baseline Interferometry (VLBI) techniques to monitor variations in the rotation of the Earth. Currently the IRIS-A network, with stations at Westford, MA, Ft. Davis, TX, Richmond, FL, and Wettzell, FRG, conducts 24-hour observing sessions every five days to produce determinations of pole position, UT1, and nutation in addition to other parameters of geophysical and astrometric interest. The resulting Earth orientation parameters (EOP) have been shown to have an accuracy of 1 to 2 milliseconds of arc in pole position, and 0.05 to 0.1 milliseconds of time in UT1. In order to observe the relatively large higher frequency variations in UT1, daily 45-minute observing sessions are conducted using the single baseline between Westford and Wettzell. Intercomparison of the UT1 values from the daily and the 5-day series indicates that the accuracy of the daily values is better than 0.1 millisecond of time.
The longer term objectives of the IRIS project include improving the monitoring of Earth orientation by increasing the sampling rate and accuracy of the observations. In April, 1987, the IRIS-P network, with stations in Kashima, Japan, Fairbanks, AK, Ft, Davis, TX, and Richmond, FL began monthly 24-hour observing sessions, and a second series of daily UT1 observing sessions was begun using the stations in Richmond and Bologna, Italy. The additional networks will provide redundancy that will improve the reliability of the system and allow the accuracy of the EOP values to be estimated.
The IRIS UT1 time series provides, for the first time, sufficient accuracy and temporal resolution to look for the few percent increase in k/C caused by the anelastic response of the mantle. Initial results presented here suggest that improved methods of accounting for the dynamics of the oceans and atmosphere may be required before the intertwined variations in UT1 can be fully separated.
The combined POLARIS-IRIS Earth orientation time series now span nearly a full cycle of the Chandler-annual beat period, beginning in late 1980. Since April 1985 there is also a nearly continuous coverage of UT1 at daily intervals. We have fit a simple model, consisting of circular 14-month and annual components and a linear drift to the polar motion series, then computed the “along-track” and “cross-track” residuals. Both sets of residuals display structure with amplitudes of tens of milliseconds of arc on time scales of months, but Fourier analysis reveals no significant peaks at shorter periods, including the 40-60 day period found in the UT1 time series.
During September, 1986, we introduced a new “quick-look” UT1 time series. The values are typically available within 7 days. The accuracy, which depends strongly on the accuracy of the X and Y pole coordinates used in the computations, ranged from 0.3 to 0.7 milliseconds during the first two weeks, but improved to about 0.1 milliseconds during the latter two weeks of the month. We plan to continue the quick-look UT1 series as a standard product of the IRIS Earth orientation monitoring service.
Introduction: The Institute of Medicine (IOM) has recommended that high-quality, evidence-based guidelines be developed for emergency medical services (EMS). The National Association of EMS Physicians (NAEMSP) has outlined a strategy that will see this task fulfilled, consisting of multiple working groups focused on all aspects of guideline development and implementation. A first step, and our objective, was a cataloguing and appraisal of the current guidelines targeting EMS providers. Methods: A systematic search of the literature was conducted in MEDLINE (1175), EMBASE (519), PubMed (14), Trip (416), and guidelines.gov (64) through May 1, 2016. Two independent reviewers screened titles for relevance to prehospital care, and then abstracts for essential guideline features, including a systematic review, a grading system, and an association between level of evidence and strength of recommendation. All disagreements were moderated by a third party. Citations meeting inclusion criteria were appraised with the AGREE II tool, which looks at six different domains of guideline quality, containing a total of 23 items rated from 1 to 7. Each guideline was appraised by three separate reviewers, and composite scores were calculated by averaging the scaled domain totals. Results: After primary (kappa 97%) and secondary (kappa 93%) screening, 49 guidelines were retained for full review. Only three guidelines obtained a score of >90%, the topics of which included aeromedical transport, analgesia in trauma, and resuscitation of avalanche victims. Only two guidelines scored between 80% and 90%, the topics of which included stroke and pediatric seizure management. One guideline, splinting in an austere environment, scored between 70% and 80%. Nine guidelines scored between 60% and 70%, the topics of which included ischemic stroke, cardiovascular life support, hemorrhage control, intubation, triage, hypothermia, and fibrinolytic use. Of the remaining guidelines, 14 scored between 50% and 60%, and 20 obtained a score of <50%. Conclusion: There are few high-quality, evidence-based guidelines in EMS. Of those that are published, the majority fail to meet established quality measures. Although a lack of randomized controlled trials (RCTs) conducted in the prehospital field continues to limit guideline development, suboptimal methodology is also commonplace within the existing literature.
Perennial grain crops are expected to sequester soil carbon (C) and improve soil health due to their large and extensive root systems. To examine the rate of initial soil C accumulation in a perennial grain crop, we compared soil under perennial intermediate wheatgrass (IWG) with that under annual winter wheat 4 years after the crops were first planted. In addition, we tested the effect of three nitrogen (N) sources on C pools: Low available N (Low N (Organic N); 90 kg N ha−1 poultry litter), moderately available N (Mid N; 90 kg N ha−1 urea) and high available N (High N; 135 kg N ha−1 urea). We measured aboveground C (grain + straw), and coarse and fine root C to a depth of 1 m. Particulate organic matter (POM-C), fractionated by size, was used to indicate labile and more stabilized soil C pools. At harvest, IWG had 1.9 times more straw C and up to 15 times more root C compared with wheat. There were no differences in the size of the large (6 mm–250 µm) or medium (250–53 µm) POM-C fractions between wheat and IWG (P > 0.05) in surface horizons (0–10 cm). Large POM-C under IWG ranged from 3.6 ± 0.3 to 4.0 ± 0.7 g C kg soil−1 across the three N rates, similar to wheat under which large POM-C ranged from 3.6 ± 1.4 to 4.7 ± 0.7 g C kg soil−1. Averaged across N level, medium POM-C was 11.1 ± 0.8 and 11.3 ± 0.7 g C kg soil−1 for IWG and wheat, respectively. Despite IWG's greater above and belowground biomass (to 70 cm), POM-C fractions in IWG and wheat were similar. Post-hoc power analysis revealed that in order to detect differences in the labile C pool at 0–10 cm with an acceptable power (~80%) a 15% difference would be required between wheat and IWG. This demonstrates that on sandy soils with low cation exchange capacity, perennial IWG will need to be in place for longer than 4 years in order to detect an accumulated soil C difference > 15%.
Universal screening for postpartum depression is recommended in many countries. Knowledge of whether the disclosure of depressive symptoms in the postpartum period differs across cultures could improve detection and provide new insights into the pathogenesis. Moreover, it is a necessary step to evaluate the universal use of screening instruments in research and clinical practice. In the current study we sought to assess whether the Edinburgh Postnatal Depression Scale (EPDS), the most widely used screening tool for postpartum depression, measures the same underlying construct across cultural groups in a large international dataset.
Ordinal regression and measurement invariance were used to explore the association between culture, operationalized as education, ethnicity/race and continent, and endorsement of depressive symptoms using the EPDS on 8209 new mothers from Europe and the USA.
Education, but not ethnicity/race, influenced the reporting of postpartum depression [difference between robust comparative fit indexes (∆*CFI) < 0.01]. The structure of EPDS responses significantly differed between Europe and the USA (∆*CFI > 0.01), but not between European countries (∆*CFI < 0.01).
Investigators and clinicians should be aware of the potential differences in expression of phenotype of postpartum depression that women of different educational backgrounds may manifest. The increasing cultural heterogeneity of societies together with the tendency towards globalization requires a culturally sensitive approach to patients, research and policies, that takes into account, beyond rhetoric, the context of a person's experiences and the context in which the research is conducted.
Epidemiology formed the basis of ‘the Barker hypothesis’, the concept of ‘developmental programming’ and today’s discipline of the Developmental Origins of Health and Disease (DOHaD). Animal experimentation provided proof of the underlying concepts, and continues to generate knowledge of underlying mechanisms. Interventions in humans, based on DOHaD principles, will be informed by experiments in animals. As knowledge in this discipline has accumulated, from studies of humans and other animals, the complexity of interactions between genome, environment and epigenetics, has been revealed. The vast nature of programming stimuli and breadth of effects is becoming known. As a result of our accumulating knowledge we now appreciate the impact of many variables that contribute to programmed outcomes. To guide further animal research in this field, the Australia and New Zealand DOHaD society (ANZ DOHaD) Animals Models of DOHaD Research Working Group convened at the 2nd Annual ANZ DOHaD Congress in Melbourne, Australia in April 2015. This review summarizes the contributions of animal research to the understanding of DOHaD, and makes recommendations for the design and conduct of animal experiments to maximize relevance, reproducibility and translation of knowledge into improving health and well-being.
Historically, alloy development with better radiation performance has been focused on traditional alloys with one or two principal element(s) and minor alloying elements, where enhanced radiation resistance depends on microstructural or nanoscale features to mitigate displacement damage. In sharp contrast to traditional alloys, recent advances of single-phase concentrated solid solution alloys (SP-CSAs) have opened up new frontiers in materials research. In these alloys, a random arrangement of multiple elemental species on a crystalline lattice results in disordered local chemical environments and unique site-to-site lattice distortions. Based on closely integrated computational and experimental studies using a novel set of SP-CSAs in a face-centered cubic structure, we have explicitly demonstrated that increasing chemical disorder can lead to a substantial reduction in electron mean free paths, as well as electrical and thermal conductivity, which results in slower heat dissipation in SP-CSAs. The chemical disorder also has a significant impact on defect evolution under ion irradiation. Considerable improvement in radiation resistance is observed with increasing chemical disorder at electronic and atomic levels. The insights into defect dynamics may provide a basis for understanding elemental effects on evolution of radiation damage in irradiated materials and may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems.
Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self-report questionnaire measure of autistic traits. However, the ability of the AQ to predict who will go on to receive a diagnosis of ASD in adults is unclear.
We studied 476 adults, seen consecutively at a national ASD diagnostic referral service for suspected ASD. We tested AQ scores as predictors of ASD diagnosis made by expert clinicians according to International Classification of Diseases (ICD)-10 criteria, informed by the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and Autism Diagnostic Interview-Revised (ADI-R) assessments.
Of the participants, 73% received a clinical diagnosis of ASD. Self-report AQ scores did not significantly predict receipt of a diagnosis. While AQ scores provided high sensitivity of 0.77 [95% confidence interval (CI) 0.72–0.82] and positive predictive value of 0.76 (95% CI 0.70–0.80), the specificity of 0.29 (95% CI 0.20–0.38) and negative predictive value of 0.36 (95% CI 0.22–0.40) were low. Thus, 64% of those who scored below the AQ cut-off were ‘false negatives’ who did in fact have ASD. Co-morbidity data revealed that generalized anxiety disorder may ‘mimic’ ASD and inflate AQ scores, leading to false positives.
The AQ's utility for screening referrals was limited in this sample. Recommendations supporting the AQ's role in the assessment of adult ASD, e.g. UK NICE guidelines, may need to be reconsidered.
Blazar OJ 287 is one of the best observed extragalactic objects. It's historical light curve goes back to 1890′s. Based on the historical behaviour Sillanpää et al. (1988) showed that OJ 287 displays large periodic outbursts, with a period of 11.7 years. We have monitored OJ 287 intensively for two years, during the OJ-94 project. This project was created for monitoring OJ 287 during its predicted new outburst in 1994. In the data archive we have over 7000 observations on OJ 287, in the radio, infrared and optical bands. This data archive contains the best ever obtained light curves for any extragalactic object. The optical light curve shows continuous variability down to time scales of tens of minutes. The variability observed in OJ 287 can be broken down to (at least) four different categories:
Phase coherent interferometers with intercontinental baselines became possible because of the development of stable frequency standards. With sufficiently stable frequency standards, no connection is necessary between the two ends of an interferometer. The first VLBI experiments were conducted by a group at the University of Florida who used an intensity interferometer with independent tape recorders for observations of Jupiter. Later, they changed to a coherent system using crystal-controlled oscillators. Since then, several interferometer systems have been developed. A Canadian group developed a system using video tape recorders at each end of the interferometer. They recorded the data in analogue form and managed to bring the two tapes together and to synchronize them to an accuracy of better than a microsecond. After synchronization, the outputs were combined and fringes extracted. Their system has a bandwidth of about 4 MHz. No-one else has attempted a wide-band analogue system.
Preliminary results are reported of a long-term program to test models of variable radio sources by direct observations of diameter changes. Although further confirmation is needed, increase in angular diameter attributed to a centimetric component of 3C 279 found in 1966 implies relativistic expansion with α ≳ 2.
In order to sort out events taking place in variable sources it is necessary to observe frequently and at many wavelengths, especially at short wavelengths.
Compact components of several radio sources were observed in the course of VLBI observations at S-band between NASA-JPL Deep Space Stations located in Australia, South Africa and California, U.S.A., during the southern summer of 1971–72. These stations were equipped with H-maser frequency standards over this period so that the fringe frequency could be determined to better than 1 mHz.
The internal consistency of the position solution could be assessed for sources observed at least three times. This varied with source declination from ± 0″.1 at a declination of 45° to ± 2″.0 near the equator.
The spread in the position solution for P0727-11, a rapid variable at the observing frequency, was also large.
Positions obtained for some other sources have been used to assist in the identification of associated optical objects.
Radio interferometric observations of extragalactic radio sources have been made with antennas at the Haystack Observatory in Massachusetts and the Owens Valley Radio Observatory in California during fourteen separate experiments distributed between September 1976 and May 1978. The components of the baseline vector and the coordinates of the sources were estimated from the data from each experiment separately. The root-weighted-mean-square scatter about the weighted mean (“repeatability”) of the estimates of the length of the 3900 km baseline was approximately 7 cm, and of the source coordinates, approximately or less, except for the declinations of low-declination sources. With the source coordinates all held fixed at the best available, a posteriori, values, and the analyses repeated for each experiment, the repeatability obtained for the estimate of baseline length was 4 cm. From analyses of the data from several experiments simultaneously, estimates were obtained of changes in the x component of pole position and in the Earth's rotation (UT1). Comparison with the corresponding results obtained by the Bureau International de l'Heure (BIH) discloses systematic differences. In particular, the trends in the radio interferometric determinations of the changes in pole position agree more closely with those from the International Polar Motion Service (IPMS) and from the Doppler observations of satellites than with those from the BIH.
The National Geodetic Survey (NGS) of the National Ocean Survey (NOS), a component of the National Oceanic and Atmospheric Administration has begun a project to establish and operate a 3-station network of permanent observatories to monitor polar-motion and Earth rotation (UT1) by radio interferometric observations of quasars. The project designation is POLARIS (POLar-motion Analysis by Radio Interferometric Surveying).
The POLARIS observatories will be equipped with a new generation of instrumentation and software, the Mark III data acquisition and processing system currently under development by a multi-organizational team.