Stress distribution and topography of Tellus Regio, Venus

The Tellus Regio area of Venus represents a subset of a narrow latitude band where Pioneer Venus Orbiter (PVO) altimetry data, line-of-sight (LOS) gravity data, and Venera 15/16 radar images have all been obtained with good resolution. Tellus Regio also has a wide variety of surface morphologic features, elevations ranging up to 2.5 km, and a relatively low LOS gravity anomaly. This area was therefore chosen in order to examine the theoretical stress distributions resulting from various models of compensation of the observed topography. These surface stress distributions are then compared with the surface morphology revealed in the Venera 15/16 radar images. Conclusions drawn from these comparisons will enable constraints to be put on various tectonic parameters relevant to Tellus Regio. The stress distribution is calculated as a function of the topography, the equipotential anomaly, and the assumed model parameters. The topography data is obtained from the PVO altimetry. The equipotential anomaly is estimated from the PVO LOS gravity data. The PVO LOS gravity represents the spacecraft accelerations due to mass anomalies within the planet. These accelerations are measured at various altitudes and angles to the local vertical and therefore do not lend themselves to a straightforward conversion. A minimum variance estimator of the LOS gravity data is calculated, taking into account the various spacecraft altitudes and LOS angles and using the measured PVO topography as an a priori constraint. This results in an estimated equivalent surface mass distribution, from which the equipotential anomaly is determined

Evolution of the east rim of the Hellas basin, Mars

The Hellas basin is a dominant feature in the ancient, southern cratered highlands of Mars. The east rim of Hellas is a complex geologic region affected by volcanism, tectonism, and channeling. A detailed study of the area between 27.5-42.4 degrees S and 260-275 degrees W was initiated to analyze the processes forming surface materials and to decipher the evolution of this geologically important highland area. Major units include Hadriaca and Tyrrhena Paterae in the north and Hesperian and Amazonian channeled plains and outflow channels in the south. A brief discussion of the findings is presented

Physical properties of lava flows on the southwest flank of Tyrrhena Patera, Mars

Tyrrhena Patera (TP) (22 degrees S, 253.5 degrees W), a large, low-relief volcano located in the ancient southern highlands of Mars, is one of four highland paterae thought to be structurally associated with the Hellas basin. The highland paterae are Hesperian in age and among the oldest central vent volcanoes on Mars. The morphology and distribution of units in the eroded shield of TP are consistent with the emplacement of pyroclastic flows. A large flank unit extending from TP to the SW contains well-defined lava flow lobes and leveed channels. This flank unit is the first definitive evidence of effusive volcanic activity associated with the highland paterae and may include the best preserved lava flows observed in the Southern Hemisphere of Mars. Flank flow unit averages, channelized flow, flow thickness, and yield strength estimates are discussed. Analysis suggests the temporal evolution of Martian magmas

Timing and formation of wrinkle ridges in the Tyrrhena Patera Region of Mars

Wrinkle ridges are distinctive linear to curvilinear arches topped by crenulated ridges and have been identified on the Moon, Mercury, and Mars. The presence of wrinkle ridges on other planetary surfaces has been used as a criterion for identifying volcanic plains. Recently, due to the presence of lava flow lobes and leveed channels, Greeley and Crown identified an area within Hesperia Planum as a flank flow unit associated with Tyrrhena Patera. Hesperia Planum surrounds Tyrrhena Patera and embays the eroded shield of the volcano to the north and south. The Tyrrhena Patera flank flow unit extends approx. 1000 km from the summit caldera to the southwest. More than 55 wrinkle ridges have been identified on this flank flow unit. The relationships between the lava flows and wrinkle ridges within the flank flow unit allow relative ages to be determined. Wrinkle ridges are classified as post flow if flow lobes appear to arch over the rises undeformed, with no evidence of flow ponding on the upstream side of the ridge, or of flows breaching the rises. Wrinkle ridges within Hesperia Planum and Tyrrhena Patera flank flow unit that trend NW-SE appear younger than the flank flow unit

Cured fish in Bangladesh. Report on a visit to Bangladesh, November 1990, on behalf of ODA Post-Harvest Fisheries Project, Bay of Bengal Programme, Madras, India

This report is based on a three week visit to Bangladesh in November 1990 by David Walker (Fish Processing and Infestation Technologist) and Martin Greeley (Marketing Economist) to examine the incidence of insect infestation in cured fish and report on both the technical and economic features of current insect control methods including the potential for improved post-harvest practices. The assignment was made on behalf of ODA for the Bay of Bengal Programme (BOBP) and included a debriefing visit to BOBP, Madras. In Bangladesh, the team included two local counterparts - S H Shamim, a socio-economist from a local research organisation, UBINIG, and Md Kador Ahmed an Inspector from the Chittagong Quality Control Office of the Department of Fisheries. The team made visits to cured fish production sites at Cox's Bazar and on islands in the Bay of Bengal including Sonadia, Dubla and Afatia Char. They observed production of cured fresh water fish in villages in Sunamganj district. They visited retail and wholesale markets in several towns including visits on three days to the major wholesale market for cured marine fish at Asadganj, Chittagong. These visits provided the opportunity to observe directly the problems of blowfly and beetle infestation and to discuss control practices with workers, managers, traders and entrepreneurs within the cured fish industry. In addition to the Ministry of Fisheries the team also visited a number of public sector agencies involved, inter alia, in research on or regulation of the Bangladesh fisheries. In practice there has been very little research or regulation of the cured fish industry. Indeed, there is not a comprehensive descriptive account of the location, organization and scale of cured fish production in Bangladesh. This is the justification for this report to include a fairly basic description of cured fish production in Bangladesh prior to discussion of insect infestation problems and controls. Many gaps remain in this description because of the lack of data on most aspects of the industry including the output levels for each product type; exported jewfish excepted. Beyond this general appreciation of the cured fish industry, the main focus of our visits and of this report is on control of insects and of possible project opportunities in this area. Our findings are that insect loss control practices being employed seem relatively effective and are economically beneficial given the sensitivity of price to quality. However, in some cases e.g. the non-approved use of DDT - current practice is potentially hazardous to the health of consumers with high measured residue levels in samples of cured fish purchased in the wholesale and retail market. There is very widespread use of dichlorvos, an insecticide similarly not approved for use on fish but there is some doubt whether a health hazard exists. Research on the potential hazards constitute the main recommendations of this mission and specific proposals have been incorporated in this report. Otherwise, no specific interventions are proposed. The socio-economic discussion highlights the difficulties of targeting project interventions to the benefit of the poor. Given the structure of economic interests in the cured fish industry, long-term programmes of human resource development and local institutional strengthening are necessary prerequisites for effective poverty alleviation programmes

Marine propeller blade tip flows

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.Bibliography: leaves 144-148.by David Scott Greeley.Ph.D

Autonomous system identification and control of MACE II using the Frequency Domain Expert algorithm

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77122/1/AIAA-1999-4586-175.pd

Prospective Study Evaluating IncobotulinumtoxinA for Cervical Dystonia or Blepharospasm: Interim Results from the First 145 Subjects with Cervical Dystonia

Background: We report the interim results from XCiDaBLE: A large prospective, observational "naturalistic" study evaluating Xeomin® (incobotulinumtoxinA) for cervical dystonia or blepharospasm in the United States. Methods: Subjects with CD are followed for 2 treatment cycles and monitored via Interactive Voice/Web Response. Subject-reported scales include the Subject Global Impression-Severity and Improvement; Cervical Dystonia Impact Profile (CDIP-58); and Work Productivity and Quality of Life (QoL) are assessed by means of an employment questionnaire and work history and the SF-12v2. Results: This ongoing study includes 145 subjects with a diagnosis of CD. The majority were female (82.3%) and White (91.0%) and had previously been treated with botulinum toxins (77.2%). There were 106 employed at the time of onset of the disease, but 12.6 years later only 44% were still employed at the time of enrolment into the study and 20% were either receiving or seeking disability benefits. However, only 44% were still employed at the time of recruitment for study participation. The mean total dose/treatment of CD was 225.2 units for the 1st injection. The CDIP-58 total score was significantly improved at four weeks post the first injection compared to baseline (p less than or equal to 0.0001). Most subjects noted improvement in their global impression assessment. No new or unexpected adverse events occurred. Discussion: The results from these interim analyses confirm previous controlled single-dose studies of incobotulinumtoxinA in terms of efficacy and safety

Surface properties of Mars' polar layered deposits and polar landing sites

On December 3, 1999, the Mars Polar Lander and Mars Microprobes will land on the planet's south polar layered deposits near (76°S, 195°W) and conduct the first in situ studies of the planet's polar regions. The scientific goals of these missions address several poorly understood and globally significant issues, such as polar meteorology, the composition and volatile content of the layered deposits, the erosional state and mass balance of their surface, their possible relationship to climate cycles, and the nature of bright and dark aeolian material. Derived thermal inertias of the southern layered deposits are very low (50–100 J m^(−2) s^(−1/2) K^(−1)), suggesting that the surface down to a depth of a few centimeters is generally fine grained or porous and free of an appreciable amount of rock or ice. The landing site region is smoother than typical cratered terrain on ∼1 km pixel^(−1) Viking Orbiter images but contains low-relief texture on ∼5 to 100 m pixel^(−1) Mariner 9 and Mars Global Surveyor images. The surface of the southern deposits is older than that of the northern deposits and appears to be modified by aeolian erosion or ablation of ground ice