Using airborne LiDAR Survey to explore historic-era archaeological landscapes of Montserrat in the eastern Caribbean

This article describes what appears to be the first archaeological application of airborne LiDAR survey to historic-era landscapes in the Caribbean archipelago, on the island of Montserrat. LiDAR is proving invaluable in extending the reach of traditional pedestrian survey into less favorable areas, such as those covered by dense neotropical forest and by ashfall from the past two decades of active eruptions by the Soufrière Hills volcano, and to sites in localities that are inaccessible on account of volcanic dangers. Emphasis is placed on two aspects of the research: first, the importance of ongoing, real-time interaction between the LiDAR analyst and the archaeological team in the field; and second, the advantages of exploiting the full potential of the three-dimensional LiDAR point cloud data for purposes of the visualization of archaeological sites and features

Prevalence and Distribution of Ranavirus in Amphibians From

Several infectious diseases are threatening amphibian species worldwide and have resulted in massmortality events across the globe. An emerging group of viral pathogens (ranaviruses) are documented to cause die-offs in amphibian populations worldwide, including in several regions of the U.S. Unfortunately, large gaps remain in our understanding of the distribution of this systemic pathogen in the U.S., including within the state of Oklahoma. To address this gap in our understanding, we carried out surveys of this infectious pathogen across 14 sites in seven southeastern Oklahoma counties in spring 2015, screening 17 amphibian species from this region. Using liver and tail tissue samples collected from individual amphibians, we screened for the presence and infection load of ranavirus. Of the 390 samples, 84 (21.5%) tested positive for ranavirus, with infection prevalence varying among species surveyed. Notably, the family Bufonidae had no samples that tested positive for ranavirus, whereas the remaining families had an infection prevalence ranging from 14–50%. Despite an overall infection prevalence of 21.5%, we detected no clinical signs of ranavirosis and all sampled individuals appeared outwardly healthy. These results provide data on the geographic and host distribution of ranavirus in southeastern Oklahoma, as well as the first documented cases of the pathogen in three species of anurans: Gastrophryne carolinensis (Eastern Narrow-mouthed Toad), G. olivacea (Western Narrow-mouthed Toad), and Pseudacris fouquettei (Cajun Chorus Frog). With widespread ranavirus infection, there is potential for transmission from abundant, widespread species to more vulnerable, state-threatened amphibians

The prevalence of vitamin B12 deficiency in a random sample from the Australian population

 Objective: Vitamin B12 deficiency is common in older adults, and may increase the risk of cognitive impairment. The distribution of vitamin B12 insufficiency in younger age groups is less studied. This study aims to assess the prevalence of vitamin B12 deficiency (<156ρmol/L) and subclinical low-normal levels (156-250ρmol/L) in a large, random sample of the Australian population across the adult life span. Methods: We examined serum vitamin B12 levels in a random sample of 1,085 men and 1,125 women aged 20-97 years between 1994 and 2006; in the Barwon Statistical Division, a regional area in south eastern Australia that is representative of the socioeconomic status of the Australian population. Results: The age-standardised prevalence of vitamin B12 deficiency in this cohort of men and women was 3.6%. Subclinical low-normal vitamin B12 levels (156-250ρmol/L) were found in 26%. Serum vitamin B12 levels declined with age among men (p-value <0.001) and were lower in men than women (p-value <0.001). Vitamin B12 levels were higher among supplement users (8.0% of the cohort). Conclusions: Vitamin B12 levels decline with age, and have been associated with neurodegenerative diseases and cognitive decline. Early intervention by diet education or supplement use to address this age-associated decline in vitamin levels may be an effective strategy to prevent decline in a significant segment of the population. Such intervention may need to start in mid-life (from 50-years of age) before the onset age-related decline in vitamin B12 levels

Pulsar Timing with the Parkes Radio Telescope for the Fermi Mission

We report here on two years of timing of 168 pulsars using the Parkes radio telescope. The vast majority of these pulsars have spin-down luminosities in excess of 10^34 erg/s and are prime target candidates to be detected in gamma-rays by the Fermi Gamma-Ray Space Telescope. We provide the ephemerides for the ten pulsars being timed at Parkes which have been detected by Fermi in its first year of operation. These ephemerides, in conjunction with the publicly available photon list, can be used to generate gamma-ray profiles from the Fermi archive. We will make the ephemerides of any pulsars of interest available to the community upon request. In addition to the timing ephemerides, we present the parameters for 14 glitches which have occurred in 13 pulsars, seven of which have no previously known glitch history. The Parkes timing programme, in conjunction with Fermi observations, is expected to continue for at least the next four years.Comment: Accepted for publication in PASA.12 page

PSRs J0248+6021 and J2240+5832: Young Pulsars in the Northern Galactic Plane. Discovery, Timing, and Gamma-ray observations

Pulsars PSR J0248+6021 (rotation period P=217 ms and spin-down power Edot = 2.13E35 erg/s) and PSR J2240+5832 (P=140 ms, Edot = 2.12E35 erg/s) were discovered in 1997 with the Nancay radio telescope during a northern Galactic plane survey, using the Navy-Berkeley Pulsar Processor (NBPP) filter bank. GeV gamma-ray pulsations from both were discovered using the Fermi Large Area Telescope. Twelve years of radio and polarization data allow detailed investigations. The two pulsars resemble each other both in radio and in gamma-ray data. Both are rare in having a single gamma-ray pulse offset far from the radio peak. The high dispersion measure for PSR J0248+6021 (DM = 370 pc cm^-3) is most likely due to its being within the dense, giant HII region W5 in the Perseus arm at a distance of 2 kpc, not beyond the edge of the Galaxy as obtained from models of average electron distributions. Its high transverse velocity and the low magnetic field along the line-of-sight favor this small distance. Neither gamma-ray, X-ray, nor optical data yield evidence for a pulsar wind nebula surrounding PSR J0248+6021. The gamma-ray luminosity for PSR J0248+6021 is L_ gamma = (1.4 \pm 0.3)\times 10^34 erg/s. For PSR J2240+5832, we find either L_gamma = (7.9 \pm 5.2) \times 10^34 erg/s if the pulsar is in the Outer arm, or L_gamma = (2.2 \pm 1.7) \times 10^34 erg/s for the Perseus arm. These luminosities are consistent with an L_gamma ~ sqrt(Edot) rule. Comparison of the gamma-ray pulse profiles with model predictions, including the constraints obtained from radio polarization data, favor emission in the far magnetosphere. These two pulsars differ mainly in their inclination angles and acceleration gap widths, which in turn explains the observed differences in the gamma-ray peak widths.Comment: 13 pages, Accepted to Astronomy & Astrophysic

Variation in developmental rates is not linked to environmental unpredictability in annual killifishes

Comparative evidence suggests that adaptive plasticity may evolve as a response to predictable environmental variation. However, less attention has been placed on unpredictable environmental variation, which is considered to affect evolutionary trajectories by increasing phenotypic variation (or bet hedging). Here, we examine the occurrence of bet hedging in egg developmental rates in seven species of annual killifish that originate from a gradient of variation in precipitation rates, under three treatment incubation temperatures (21, 23, and 25 degrees C). In the wild, these species survive regular and seasonal habitat desiccation, as dormant eggs buried in the soil. At the onset of the rainy season, embryos must be sufficiently developed in order to hatch and complete their life cycle. We found substantial differences among species in both the mean and variation of egg development rates, as well as species-specific plastic responses to incubation temperature. Yet, there was no clear relationship between variation in egg development time and variation in precipitation rate (environmental predictability). The exact cause of these differences therefore remains enigmatic, possibly depending on differences in other natural environmental conditions in addition to precipitation predictability. Hence, if species-specific variances are adaptive, the relationship between development and variation in precipitation is complex and does not diverge in accordance with simple linear relationships

Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) after nine years of operation: a summary

Mars Express, the first European interplanetary mission, carries the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) to search for ice and water in the Martian subsurface. Developed by an Italian–US team, MARSIS transmits low-frequency, wide-band radio pulses penetrating below the surface and reflected by dielectric discontinuities linked to structural or compositional changes. MARSIS is also a topside ionosphere sounder,transmitting a burst of short, narrow-band pulses at different frequencies that are reflected by plasma with varying densities at different altitudes.The radar operates since July 2005, after the successful deployment of its 40 m antenna, acquiring data at altitudes lower than 1200 km. Subsurface sounding (SS)data are processed on board by stacking together a batch of echoes acquired at the same frequency. Onground, SS data are further processed by correlating the received echo with the transmitted waveform and compensating de-focusing caused by the dispersive ionosphere. Ground processing of active ionospheric sounding (AIS)data consists in the reconstruction of the electron density profile as a function of altitude. MARSIS observed the internal structure of Planum Boreum outlining the Basal Unit, an icy deposit lying beneath the North Polar Layered Deposits thought to have formed in an epoch in which climate was markedly different from the current one.The total volume of ice in polar layered deposits could be estimated, and parts of the Southern residual ice cap were revealed to consist of 10 m of CO2 ice. Radar properties of the Vastitas Borealis Formation point to the presence of large quantities of ice buried beneath the surface. Observations of the ionosphere revealed the complex interplay between plasma, crustal magnetic field and solar wind, contributing to space weather studies at Mars. The presence of three-dimensional plasma structures in the ionosphere was revealed for the first time. MARSIS could successfully operate at Phobos, becoming the first instrument of its kind to observe an asteroid-like body. The main goal pursued by MARSIS, the search for liquid water beneath the surface, remains elusive. However, because of the many factors affecting detection and of the difficulties in identifying water in radar echoes, a definitive conclusion on its presence cannot yet be drawn

Evaluation of an International Entrepreneur Exchange Program: Impacts, Lessons Learned, and Implications for Agricultural Development

This study evaluated a two-way, visitor exchange project for entrepreneurship development between three African countries and the United States. The study’s purpose was to determine outcomes, understand lessons learned, and derive implications for international agricultural development. Findings of the study confirm visiting African Entrepreneur Fellows (AEFs) developed entrepreneurial knowledge, gained business skills, and acquired positive attitudes toward U.S. business and culture. The majority of AEFs had applied acquired knowledge and skills to improve their businesses and promoted open economic ideals, business ethics, and human rights in their businesses. As a result, AEFs were able to expand their business into new ventures, improve customer services, establish communication networks, and serve their communities. Visitor exchange, entrepreneurship-building programs are effective strategies in contributing to development efforts in developing countries. Paying due attention to the selection and matching of U.S. mentors with the business interests and learning needs of international fellows is necessary to ensure their learning expectations are met. It is important to assign international participants with suitable mentors for longer periods of time to increase the likelihood of receiving more in-depth learning experiences and develop lasting professional relationships to further collaboration. Realization of the potential of entrepreneurship-focused, visitor exchange programs between nations as a strategy for international agricultural development is the major implication of this study

Selection of both habitat and genes in specialized and endangered caribou

Genetic mechanisms determining habitat selection and specialization of individuals within species have been hypothesized, but not tested at the appropriate individual level in nature. In this work, we analyzed habitat selection for 139 GPS-collared caribou belonging to 3 declining ecotypes sampled throughout Northwestern Canada. We used Resource Selection Functions comparing resources at used and available locations. We found that the 3 caribou ecotypes differed in their use of habitat suggesting specialization. On expected grounds, we also found differences in habitat selection between summer and winter, but also, originally, among the individuals within an ecotype. We next obtained Single Nucleotide Polymorphisms (SNPs) for the same caribou individuals, we detected those associated to habitat selection, and then identified genes linked to these SNPs. These genes had functions related in other organisms to habitat and dietary specializations, and climatic adaptations. We therefore suggest that individual variation in habitat selection was based on genotypic variation in the SNPs of individual caribou, indicating that genetic forces underlie habitat and diet selection in the species. We also suggest that the associations between habitat and genes that we detected may lead to lack of resilience in the species, thus contributing to caribou endangerment. Our work emphasizes that similar mechanisms may exist for other specialized, endangered species

Genetic aberrations of c-myc and CCND1 in the development of invasive bladder cancer

Detrusor muscle invasive transitional cell carcinoma is associated with poor prognosis and is responsible for the majority of bladder cancer related deaths. Amplifications of c-myc and CCND1 are associated with detrusor-muscle-invasive transitional cell carcinoma, however, their precise role in driving disease progression is unclear. Fluorescence in situ hybridisation on archival tissue from 16 patients with primary diagnosis of ⩾pT2 transitional cell carcinoma and 15 cases with primary pTa/pT1 disease subsequently progressing to detrusor-muscle-invasion was performed, in the latter group both pre and post muscle invasive events were studied. No patients presenting with ⩾pT2 had amplification of c-myc, two out of 16 (12.5%) had CCND1 amplification. Of patients who developed ⩾pT2, two out of 15 (13.3%) had amplification of c-myc, both in ⩾pT2, five out of 15 (33.3%) had CCND1 amplification, two in pTa/pT1 tumours, three in ⩾pT2 transitional cell carcinomas. In total, two out of 31 (6.5%) of patients' ⩾pT2 TCCs were amplified for c-myc and six out of 31 (19%) were amplified for CCND1. Eighty-seven per cent (40 out of 46) of tumours were polysomic for chromosome 8 and 80% (37 out of 46) were polysomic for chromosome 11 and this reflected the high copy numbers of c-myc and CCND1 observed. In almost all cases an increase in c-myc/CCND1 copy number occurred prior to invasion and persisted in advanced disease. Amplification of CCND1 or alterations in c-myc/CCND1 early in bladder cancer may have clinical relevance in promoting and predicting progression to detrusor-muscle-invasive transitional cell carcinoma