A conceptual design and operational characteristics for a Mars rover for a 1979 or 1981 Viking science mission

The feasibility of a small Mars rover for use on a 1979 or 1981 Viking mission was studied and a preliminary design concept was developed. Three variations of the concept were developed to provide comparisons in mobility and science capability of the rover. Final masses of the three rover designs were approximately 35 kg, 40 kg, and 69 kg. The smallest rover is umbilically connected to the lander for power and communications purposes whereas the larger two rovers have secondary battery power and a 2-way very high frequency communication link to the lander. The capability for carrying Viking rovers (including development system) to the surface of Mars was considered first. It was found to be feasible to carry rovers of over 100 kg. Virtually all rover systems were then studied briefly to determine a feasible system concept and a practical interface with the comparable system of a 1979 or 1981 lander vehicle

Automated Mars surface sample return mission concepts for achievement of essential scientific objectives

Mission concepts were investigated for automated return to Earth of a Mars surface sample adequate for detailed analyses in scientific laboratories. The minimum sample mass sufficient to meet scientific requirements was determined. Types of materials and supporting measurements for essential analyses are reported. A baseline trajectory profile was selected for its low energy requirements and relatively simple implementation, and trajectory profile design data were developed for 1979 and 1981 launch opportunities. Efficient spacecraft systems were conceived by utilizing existing technology where possible. Systems concepts emphasized the 1979 launch opportunity, and the applicability of results to other opportunities was assessed. It was shown that the baseline missions (return through Mars parking orbit) and some comparison missions (return after sample transfer in Mars orbit) can be accomplished by using a single Titan III E/Centaur as the launch vehicle. All missions investigated can be accomplished by use of Space Shuttle/Centaur vehicles

Mission and sensor concepts for coastal and ocean monitoring using spacecraft and aircraft

A concept developed for a 1990 oceanic mission which places strong emphasis on coastal monitoring needs is described and analysed. The concept assumes that use of one active spacecraft in orbit and one on standby plus airplanes and data collection platforms which provide continuing complementary coverage and surface truth. The coastal measurement requirements and goals, the prospective oceanic and coastal sensors, the spacecraft and aircraft data platforms, and the prospective orbit designs are discussed

Electric Polarizability of Neutral Hadrons from Lattice QCD

By simulating a uniform electric field on a lattice and measuring the change in the rest mass, we calculate the electric polarizability of neutral mesons and baryons using the methods of quenched lattice QCD. Specifically, we measure the electric polarizability coefficient from the quadratic response to the electric field for 10 particles: the vector mesons $\rho^0$ and $K^{*0}$; the octet baryons n, $\Sigma^0$, $\Lambda_{o}^{0}$, $\Lambda_{s}^{0}$, and $\Xi^0$; and the decouplet baryons $\Delta^0$, $\Sigma^{*0}$, and $\Xi^{*0}$. Independent calculations using two fermion actions were done for consistency and comparison purposes. One calculation uses Wilson fermions with a lattice spacing of $a=0.10$fm. The other uses tadpole improved L\"usher-Weiss gauge fields and clover quark action with a lattice spacing $a=0.17$fm. Our results for neutron electric polarizability are compared to experiment.Comment: 25 pages, 20 figure

Histotripsy of the Prostate in a Canine Model: Characterization of Post-Therapy Inflammation and Fibrosis

Introduction: Histotripsy is a nonthermal, noninvasive, pulsed ultrasound technology that homogenizes tissue within the targeted volume. From previous experiments, it appeared that the resultant fibrotic response from histotripsy was limited compared with the typical tissue response seen after thermoablation. The objective of this study was to characterize the inflammatory response and quantify patterns of collagen deposition 6 weeks after in vivo canine prostate histotripsy. Methods: Histotripsy was applied to the left half of eight canine prostates to produce an intraparenchymal zone of tissue homogenization. Six weeks after treatment, prostates were harvested, sectioned, and stained with hematoxylin and eosin for histologic evaluation, CD3, CD20, and Mac387 immunohistochemistry to characterize the inflammatory components, and picrosirius red staining to identify collagen. Results: Seven of eight treated prostates exhibited only minimal residual inflammation. Visual microscopic analysis of picrosirius red slides revealed a band of dense collagen (0.5?mm wide) immediately adjacent to the cavity produced by histotripsy. This was surrounded by a second band (1?mm wide) of less dense collagen interspersed among glandular architecture. A lobar distribution of epithelial atrophy and basal cell hyperplasia reminiscent of periurethral glands and ducts was apparent surrounding the margin of the treatment cavities. Tissue loss (-31%) was apparent on the treated side of all prostates while four demonstrated a net decrease in collagen content. Conclusions: In vivo histotripsy of canine prostate produced a decrease in prostate volume coupled with a limited inflammatory and fibrotic response. A narrow (1.5?mm) band of fibrosis around the empty, reepithelialized treatment cavity was observed 6 weeks after treatment. In four cases, an overall reduction in collagen content was measured. Further studies are planned to correlate these histologic findings with alteration in mechanical tissue properties and to explore histotripsy strategies for treatment of benign prostatic hyperplasia that optimize tissue volume removal with minimization of fibrosis.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140079/1/end.2014.0585.pd

Drift Macroalgal Distribution In Northern Gulf of Mexico Seagrass Meadows

Drift macroalgae, often found in clumps or mats adjacent to or within seagrass beds, can increase the value of seagrass beds as habitat for nekton via added food resources and structural complexity. But, as algal biomass increases, it can also decrease light availability, inhibit faunal movements, smother benthic communities, and contribute to hypoxia, all of which can reduce nekton abundance. We quantified the abundance and distribution of drift macroalgae within seagrass meadows dominated by turtle grass Thalassia testudinum across the northern Gulf of Mexico and compared seagrass characteristics to macroalgal biomass and distribution. Drift macroalgae were most abundant in areas with higher seagrass shoot densities and intermediate canopy heights. We did not find significant relationships between algal biomass and point measures of salinity, temperature, or depth. The macroalgal genera Laurencia and Gracilaria were present across the study region, Agardhiella and Digenia were collected in the western Gulf of Mexico, and Acanthophora was collected in the eastern Gulf of Mexico. Our survey revealed drift algae to be abundant and widespread throughout seagrass meadows in the northern Gulf of Mexico, which likely influences the habitat value of seagrass ecosystems

Draft Genome of a Type 4 Pilus Defective Myxococcus xanthus Strain, DZF1

Myxococcus xanthus is a member of the Myxococcales order within the deltaproteobacterial subdivision. Here, we report the whole-genome shotgun sequence of the type IV pilus (T4P) defective strain DZF1, which includes many genes found in strain DZ2 but absent from strain DK1622

Draft Genome Sequence of Myxococcus xanthus Wild-Type Strain DZ2, a Model Organism for Predation and Development

Myxococcus xanthus is a member of the Myxococcales order within the Deltaproteobacteria subdivision. The myxobacteria reside in soil, have relatively large genomes, and display complex life cycles. Here, we report the whole-genome shotgun sequence of strain DZ2, which includes unique genes not found previously in strain DK1622

No evidence for circulating HuD-specific CD8+ T cells in patients with paraneoplastic neurological syndromes and Hu antibodies

Aim: In paraneoplastic neurological syndromes (PNS) associated with small cell lung cancer (SCLC) and Hu antibodies (Hu-PNS), Hu antigens expressed by the tumour hypothetically trigger an immune response that also reacts with Hu antigens in the nervous system, resulting in tumour suppression and neuronal damage. To gain more insight into the hypothesized CD8+T cell-mediated immune pathogenesis of these syndromes, we searched for circulating HuD-specific CD8+T cells in a large cohort of Hu-PNS patients and controls. Patients and methods: Blood was tested from 43 Hu-PNS patients, 31 Hu antibody negativ