Solar sailing - mission opportunities and innovative technology demonstration

Solar sailing is a unique and elegant form of propulsion that transcends reliance on reaction mass. Rather than carrying propellant, solar sails acquire momentum from photons, the quantum packets of energy from which sunlight is composed. In addition, since solar sails are not limited by reaction mass, they can provide continual acceleration, limited only by the lifetime of the sail film in the space environment. Therefore, solar sails can expand the envelope of possible missions, enabling new high-energy mission concepts that are essentially impossible with conventional reaction propulsion, and enhancing current mission concepts by lowering launch mass and reducing trip times

Evaluation of the effects of September hunting seasons on Canada geese in Nebraska

Populations of temperate-nesting Canada geese (Branta canadensis) have increased in Nebraska, USA, resulting in an increased number of nuisance and damage complaints. September hunting seasons were initiated in southeastern Nebraska in 2004 to reduce populations of Canada geese. We analyzed band recoveries from Canada geese banded in southeastern Nebraska during their hatch-year (HY) or after-hatch-year (AHY) to determine whether September hunting seasons affected survival, harvest, and recovery rates. Survival analyses revealed that HY geese had higher survival than AHY geese (SAHY = 0.696, 95% CI = 0.679–0.713; SHY = 0.896, 95% CI = 0.786–0.953) and September seasons did not affect survival of geese in southeastern Nebraska. Geese banded in the geographic zone with the September seasons (southeastern Nebraska) had the same survival as did geese outside the hunt zone (northeastern Nebraska; S = 0.711, 95% CI = 0.666–0.752). September hunting seasons affected timing of band recovery; 23–49% of annual band recoveries occurred during the month of September. Prior to the initiation of the September seasons, the highest percent of recoveries occurred during November. The September seasons appeared to temporally redistribute harvest but did not reduce survival for populations of Canada geese in southeastern Nebraska. Continuation of the season may not be warranted, because management does not appear to be affecting AHY survival, which is needed to reduce the population. Additional or new methods are likely needed to control populations of temperate-nesting Canada geese in Nebraska and managers should evaluate the effectiveness of these methods as they are implemented

Avian Influenza Virus Prevalence in Migratory Waterfowl in the Central Flyway, 2007–2009

Highly pathogenic avian influenza (HPAI H5N1) poses risks to wild birds, poultry, and humans. Personnel with the United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, state game agencies, and tribal cooperators collected \u3e36,000 migratory birds from 2007–2009 to test for HPAI virus. Species from the dabbling duck, diving duck, and geese and swans functional groups were collected in all 10 states of the Central Flyway. Numerous combinations of the 16 hemaglutinin (H) and 9 neuraminidase (N) subtypes were discovered, but no HPAI H5N1 was found. The dabbling duck functional group had significantly higher (p \u3c 0.001) prevalence of AIV than other functional groups and should be the focus of future surveillance

Population and Spatial Dynamics of Resident Canada Geese in Southeastern Nebraska

In response to increasing populations, damage complaints, and a desire to understand population and spatial dynamics, we studied population size, survival rates, home ranges, movements, and site fidelity of female resident Canada geese (Branta canadensis) at 18 study sites within 23 km of Lincoln, Nebraska, during 1991–1994. Based on mean flock size (x̄ = 93) and number of collared geese in flocks (x̄ = 13), the estimated population of resident Canada geese was nearly 4,000. Estimated monthly survival for female Canada geese was 0.94, mean home range was 25 km2, and mean maximum distance moved between use areas was 13 km. Collared female Canada geese exhibited strong site fidelity, with 16% of relocated individuals observed at only 1 location during a single year. Other collared geese were observed at a single site during 75% of all observations. Our findings suggest that management efforts to address complaints about nuisance Canada geese must be implemented on the local level to be successful

Heliopause explorer: a sailcraft mission to the outer boundaries of the solar system

Solar sail technology holds the promise of enhancing the interplanetary transportation infrastructure for low-cost space exploration missions in the new millennium, by exploiting the freely available, space-pervading resource of solar radiation pressure for primary propulsion. Despite the large distances to the Sun and the reduced solar radiation pressure, fast missions to the outer edge of our solar system belong to the promising mission applications of solar sails. In order to realize such a mission, the sailcraft would first perform a so-called "solar photonic assist", approaching the Sun to less than 0.3 AU thus exploiting the increased solar radiation pressure, to pick up enough orbital energy to enter a hyperbolic orbit. This concept has been extended to a double and triple solar approach which reduces the requirement for very high area-to-mass ratios of the sailcraft. The target distance of the Heliopause Explorer mission is set to 200 AU. The science objective was defined as to allow the Heliopause Explorer to perform in situ observations which cannot be obtained within the remaining life time of the two Voyager spacecraft. A first feasibility study was initiated to derive technology requirements for the realization of such a challenging deep space mission

Space station logistic support by ARIES

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Genotype-phenotype correlations and novel molecular insights into the DHX30-associated neurodevelopmental disorders.

BACKGROUND We aimed to define the clinical and variant spectrum and to provide novel molecular insights into the DHX30-associated neurodevelopmental disorder. METHODS Clinical and genetic data from affected individuals were collected through Facebook-based family support group, GeneMatcher, and our network of collaborators. We investigated the impact of novel missense variants with respect to ATPase and helicase activity, stress granule (SG) formation, global translation, and their effect on embryonic development in zebrafish. SG formation was additionally analyzed in CRISPR/Cas9-mediated DHX30-deficient HEK293T and zebrafish models, along with in vivo behavioral assays. RESULTS We identified 25 previously unreported individuals, ten of whom carry novel variants, two of which are recurrent, and provide evidence of gonadal mosaicism in one family. All 19 individuals harboring heterozygous missense variants within helicase core motifs (HCMs) have global developmental delay, intellectual disability, severe speech impairment, and gait abnormalities. These variants impair the ATPase and helicase activity of DHX30, trigger SG formation, interfere with global translation, and cause developmental defects in a zebrafish model. Notably, 4 individuals harboring heterozygous variants resulting either in haploinsufficiency or truncated proteins presented with a milder clinical course, similar to an individual harboring a de novo mosaic HCM missense variant. Functionally, we established DHX30 as an ATP-dependent RNA helicase and as an evolutionary conserved factor in SG assembly. Based on the clinical course, the variant location, and type we establish two distinct clinical subtypes. DHX30 loss-of-function variants cause a milder phenotype whereas a severe phenotype is caused by HCM missense variants that, in addition to the loss of ATPase and helicase activity, lead to a detrimental gain-of-function with respect to SG formation. Behavioral characterization of dhx30-deficient zebrafish revealed altered sleep-wake activity and social interaction, partially resembling the human phenotype. CONCLUSIONS Our study highlights the usefulness of social media to define novel Mendelian disorders and exemplifies how functional analyses accompanied by clinical and genetic findings can define clinically distinct subtypes for ultra-rare disorders. Such approaches require close interdisciplinary collaboration between families/legal representatives of the affected individuals, clinicians, molecular genetics diagnostic laboratories, and research laboratories