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To investigate single leg standing balance in males with mid-portion Achilles tendinopathy (AT).Cross sectional case study.Centre of pressure (COP) path length was measured using a Wii Balance Board (WBB) in 21 male participants (20-60 years) with unilateral mid-portion AT during single-limb standing on each limb with eyes open and closed. Ultrasound imaging of both Achilles tendons was also performed by one blinded assessor, and the anteroposterior (AP) thickness and presence of pathology was determined. Comparisons were made between symptomatic and asymptomatic sides for key outcomes, and correlation between COP path length and variables of interest were investigated.Symptomatic Achilles tendons demonstrated significantly increased AP tendon thickness (p0.001). Participants with AT demonstrated increased COP path length (sway amplitude) on their affected side during the eyes closed task (p=0.001). Increased tendon thickness was associated with increased sway amplitude during the eyes open task on both the affected (rho=0.44, p=0.045) and unaffected sides (rho=0.62, p=0.003).In males with AT, single-leg standing balance with eyes closed is impaired on the symptomatic side. This indicates that neuromuscular deficits affecting functional ability may be present in people with AT during more challenging balance activities. It is unclear if this deficit precedes the onset of symptoms, or is a consequence of tendon pain. Work is now needed to understand the mechanisms that may explain standing balance deficits among people with AT.

The Boot wetland treatment system is a 115-acre, hydrologically altered cypress-gum wetland in Polk County, Florida. The Poinciana Wastewater Treatment Plant No. 3 has discharged secondary effluent to the bermed Boot wetland since August 1984. Before that time this natural wetland had been affected adversely by forestry, drainage, and surrounding development which contributed to dying trees and a groundcover of invasive upland plants. In accordance with the Florida Department of Environmental Protection's Wetlands Application Rule (Chapter 62-611, F.A.C.), a routine biological and water quality monitoring program has been in effect since October 1990. Components of the biological monitoring program include surveys of canopy and subcanopy, herbaceous and shrub groundcover species, benthic macroinvertebrates, fish, and nuisance mosquitoes. Effluent addition to the Boot wetland has resulted in continuous wetland inundation with a typical water depth of 2.5 to 3.0 feet for the past 15 years. Dominance and density of trees has steadily increased, upland invader species were eliminated, and stable plant, fish, and invertebrate communities were established. The long term biological data from this treatment wetland is compared to data from other natural treatment wetlands and a control wetland.

The Boot WTS is a 46.5-ha, hydrologically altered cypress-gum wetland in Polk County, Florida. Poinciana Wastewater Treatment Plant No. 3 has discharged advanced secondary treated effluent to the Boot WTS since August 1984. Comprehensive operational monitoring has been ongoing since 1990. The Boot WTS has provided consistent removal of nitrogen and phosphorus. Influent total nitrogen (TN) and total phosphorus (TP) concentrations averaged approximately 10.0 mg/L and 2.5 mg/L at an average hydraulic loading rate (HLR) of 0.2 cm/d. Wetland effluent concentrations for TN and TP averaged 1.8 mg/L and 1.2 mg/L. Available flow and water quality data were used to develop estimates of the first-order removal rate, k, for TN (14 m/y) and TP (1.8 m/y). These removal rates are within the range of values for other forested treatment wetlands. Biochemical oxygen demand (2.2 mg/L) and total suspended solids (4.9 mg/L) in the influent are near background levels for forested wetlands and are not significantly reduced with passage through the system.

Water quality improvement is generally the primary objective of treatment wetlands. Creation of wildlife habitat is an inevitable outcome of these projects. However, an increasing number of treatment wetland projects have been purposely designed and operated to enhance their beneficial utility to wildlife and humans. This trend to multi-purpose treatment wetlands has broadened the basis for assessing the advantages of this natural treatment alternative. There are at least 21 treatment wetlands in the U.S. that were implemented with wildlife habitat creation and/or human use as principal goals. A number of treatment wetlands outside the U.S. also share these priorities. Hundreds of other wetlands have collected and reported quantitative data on wildlife and/or human uses. The North American Treatment Wetland Database (NADB) has been expanded to include critical wildlife habitat and human use data. This paper provides a preliminary inventory of these habitat and human use treatment wetlands, summarizes lessons learned, and identifies additional data needs.

A cosmid clone containing the ovine and C epsilon and C alpha immunoglobulin heavy chain genes was isolated and characterised. Restriction mapping and sequence analysis showed a high degree of similarity between the bovine and ovine C epsilon loci. Restriction fragment length polymorphism (RFLP) analysis of sheep genomic DNA revealed Mendelian inheritance of polymorphisms with identical variation in allele size for various restriction enzymes. This identical variation suggested that a deletion of approximately 100 bp existed at the 5' end of the smaller alleles.

We report on the conductivity, thermopower and magnetic susceptibility of the molecular conductor Cs[Pd(dmit) 2 ] 2 . This material contains stacks of acceptor groups arranged in sheets separated by the cations, with appreciable dimerisation of the acceptor groups along the stack direction. It shows metallic properties at room temperature, but on cooling there is a metal-insulator transition at 56.5 K accompanied by a structural distortion which opens an energy gap at the Fermi level. The metallic state is stablised tolow temperature at pressures above 9 kbar.

New complex tissue microstructure estimators have been presented recently in order to elucidate white matter fibre orientations. Since these algorithms are based on the diffusion- weighted signal profile, the estimations are affected by noise artefacts. The proven robustness of these methods cannot counteract distortions since the statistical Rician behavior has not been taken into account. In this study, two techniques to counteract the noise distortions are presented to improve the fibre orientation estimations. Simulations and in vivo experiments show an improvement in the angular resolution and convergence of the results. One of these strategies represents a good compromise between computational cost and result improvements.

A deconvolution approach, based on a multi-tensor model, is presented to solve fiber crossing in diffusion MRI. In order to provide a direct physical interpretation of the signal generation process, we re-wrote the classical multi-tensor model, identifying a significant scalar parameter alpha to characterize the deconvolution process. Simulations show that, in presence of noise, the method is able to correctly separate fiber crossing. Application on in-vivo data highlights the ability of our approach to distinguish more than two fibers within the same voxel, suggesting its application in fiber tracking or connectivity studies even of complex brain structures.

A deconvolution approach is presented to solve fiber crossing in diffusion magnetic resonance imaging. In order to provide a direct physical interpretation of the signal generation process, we started from the classical multicompartment model and rewrote this in terms of a convolution process, identifying a significant scalar parameter alpha to characterize the physical system response. Deconvolution is performed by a modified version of the Richardson-Lucy algorithm. Simulations show the ability of this method to correctly separate fiber crossing, even in the presence of noisy data, with lower signal-to-noise ratio, and imprecision in the impulse response function imposed during deconvolution. The in vivo data confirms the efficacy of this method to resolve fiber crossing in real complex brain structures. These results suggest the usefulness of our approach in fiber tracking or connectivity studies.

Describes a self-contained CTD system to collect temperature and salinity profiles from vessels underway at speeds up to 20 knots. An internally recording CTD housed in a streamlined body is freely dropped on a tether line deployed at high speed. A prototype with 850 m of line has reached 370 m from a vessel travelling at 10 knots. A mathematical model predicts that with a suitable line, the following depths can be reached depending on the speed: 900 m at 14 knots, 600 m at 18 knots and 370 m at 22 knots. This system is suitable for operation with a minimum of human intervention even from vessels with very high freeboard. The ultimate goal is to develop a system in which the entire launch-deployment-recovery cycle will be initiated by a single signal from the bridge of the vessel. >

Raytheon E-Systems has designed a Programmable Digital Receiver (PDRx) Multi-chip Module (MCM) for use in aerospace applications. The PDRx MCM is able to overcome the technical limitations of analog receivers without the size, power, and weight penalties typically associated with digital receiver technology. The PDRx design is comprised of four digital receiver channels accepting 16-bit-wide data streams at a frequency of 33 MHz (roughly a 10 MHz bandwidth per channel) with user programmable functions such as bandshifting, filtering, and postprocessing. The PDRx design is made possible through the use of highly efficient DSP algorithms implemented in VLSI technology, coupled with the processing power of 100 Mflops. The paper details solutions to some of the mechanical issues encountered in this design. These issues include the substrate design, ringframe design, thermal design, and lid concerns of the MCM.

Abstract Vector infidelity is the failure of ocean-bottomseismic geophones to respond isotropically to incoming seismic energy. With the rising popularity of multi-componentocean bottom seismic data, the issue of vector infidelity is becoming increasingly important. There are numerous causes of vector infidelity, which may be due to seafloor conditions, acquisition equipment or even processing. We illustrate this with a catalogue of examples, highlighting the effects on the data and the final processed image, and we present some techniques to correct for these infidelities. Introduction Traditional marine seismic acquisition, using streamers of hydrophones, only records the pressure field at the receivers. Ocean bottom seismic acquisition, on the other hand, typically uses four component sensors in order to record the full wavefield at the receivers. While this provides moreinformation about the true elastic nature of the earth, it also leads to more a complex processing flow. One of the first steps in this flow should be to correct for possible vector infidelity in the data. This occurs for numerous reasons. The cable or node is physically located on the seafloor so that the seafloor itself is a cause of vector infidelity. Spatial variations in the seafloor conditions can alsolead to variable coupling, and may cause a cable to lay in an odd position. For example, a rock could cause the cable to be twisted, leading to orientation errors, while a small hollow could cause the geophone to not be in contact with the seafloor at all. As the cables are layed down they twist slowly, so thatthere is not usually a preferred top and bottom. Typically the geophones are gimbaled such that the vertical component remains vertical. This gimbal is very similar to a heavilydamped pendulum. However, because the gimbal can move, even though it is heavily damped, it often leads to crosstalkbetween the horizontal and vertical components, which shows up as converted wave energy on the vertical component. Fixed geophones may help reduce this, and would be cheaper to manufacture, but would add further complications to the processing. The geometry of the cable also leads to vector infidelity. The cable is stiffer in the in-line direction so the in-line component of the recorded data usually has a higher frequency content. The coupling is typically better in the in-line direction than in the crossline. There is also evidence that cables mayroll when struck by the seismic wavefield, and the resulting motion is then superposed on the data of the crossline component. These considerations, combined with the difficulties of placing cables in areas where the seafloor may be crowded, have led to recent interest in node technology. Nodes have more isotropic geometries and so should have fewer vectorinfidelity issues than cables. However, there may still be problems with coupling, and also problems due to the gimbals, so it is likely that a vector fidelity correction will still be needed.

Previous work using Southern analysis of genomic DNA detected a polymorphism at the 5′ end of the sheep and cattle IgE gene. Identical length differences found between fragments following digestion with restriction enzymes indicated that the basis for the polymorphism was an insertion/deletion event. To characterise the polymorphism, the entire cattle and sheep Ce genes were sequenced including 668 bp of 5′ untranslated DNA. Sequence comparison revealed a high degree of similarity between the ovine and bovine genes at both the nucleotide and amino acid level. A feature of the 5′ untranslated DNA was the presence of an 87 bp repeat starting at −365 upstream of the Ce start site. PCR primers were designed to span most of the 5′ untranslated sequence, including the repeat unit, and used to amplify genomic DNA from a panel of 40 sheep. Three alleles were found with frequencies of 0.7, 0.29, 0.01 which were identical to the Southern analysis results. Sequencing of the two commonest alleles revealed the basis for the polymorphism was a 36 bp deletion from the 87 bp repeat. Association studies in a sheep selection flock phenotypically assessed for parasite resistance found a highly significant association between one of the IgE alleles and resistance to the intestinal nematode parasite Trichostrongylus colubriformis ( P =0.005). Attempts to confirm this finding in two other flocks using linkage analysis and genotype association failed to find any significant associations between the IgE polymorphism and resistance to either T. colubriformis or Haemonchus contortus .

The dynamics of several surface cleaning processes for silicon were investigated in a UHV environment using an in situ ellipsometric technique. Low energy argon ion bombardment followed by annealing, and thermal treatments alone were studied. We show that the only reliable procedure that provides a surface that is both oxide free and optically flat involves flashing the sample above 1200°C.

The admittance properties of a new type of semiconductor diode, the SIS (semiconductor-insulator-semiconductor) device, have been investigated experimentally. A fabrication technique is described which enables the necessary sandwich structure of two semiconductors (preferably single crystal), separated by a dielectric layer, to be obtained. The capacitance-voltage and conductance-voltage curves for a variety of SIS diodes are presented. The influence of surface states and oxide charge on the electrical characteristics is readily seen in the comparison of observed data with theoretical results for the corresponding ideal diodes. Addition of surface state, oxide charge, and other nonideal effects to the ideal SIS theory allows a good qualitative fit to be made to the experimentally observed data.

A new type of surface barrier transistor has been investigated in which two junctions are employed each consisting of a thin conducting oxide or insulator between a metal and a semiconductor. The transistor behaviour of a structure composed of two such MIS contacts and a third base contact has been studied as a function of oxide thickness and contact separation distance. Two distinct classes of transistor action are observed each depending on a different mechanism of current transfer through the insulator of the individual formed diodes. The distinguishing feature between these two classes was found to be common base current gain, hFB. Devices characterized by hFB > 1 were noted to involve current conduction through the oxide via tunneling processes while those with hFB

A d.c. tunnel current saturation under negative bias is observed for N -type MOS devices when average oxide thicknesses of d 0 A and non-degenerate (10Ω cm) semiconductors are employed. A model is proposed that allows the voltage distribution across devices in such a non-equilibrium situation to be calculated. Theoretical tunnel current expressions are derived and a comparison with experimental results made. The dependence of the existence of this saturation on semiconductor doping concentration, oxide thickness, and minority carrier injection is investigated. Consideration of band tunnel currents, and the effects of surface state charge, oxide charge, and work function differences on these currents, is shown to be sufficient to explain much of the observed current-voltage characteristic.

The variation of temperature and salinity on various level surfaces and isopycnal surfaces at several locations within the C-scale array is investigated. It is shown that simple one-dimensional models applied to fixed locations are not likely to be applicable due to the large currents in the area. The horizontal gradients of temperature, salinity, and mixed-layer depth are shown to be consistent with net heat and fresh-water inputs and advection by the near-surface current field.

Live and dead racing pigeons (Columba livia) from five lofts in Norfolk and Suffolk were examined clinically and cultured for Mycoplasma spp. Both clinically healthy birds and those showing signs of mild respiratory disease were included. The oropharynx was the culture site for 130 live birds, the nasal sinuses and other tissues for 58 carcases. Mycoplasma columbinum, M. columborale and M. columbinasale were isolated from the oropharynges and nasal sinuses; M. columbinum and M. columbinasale from the brain and M. columbinum and M. columborale from lungs and air sacs. One or more of these three Mycoplasma spp. was isolated at necropsy from 28% of 58 pigeons. Only 11% of 37 pigeons reacted sero-logically by the metabolism inhibition test to M. columbinum and none to M. columborale. Twenty-five birds examined for M. gallisepticum antibody by the haemagglutination-inhibition test were negative. No sex or age predilection to infection with Mycoplasma was apparent. About 10% of pigeons in all five lofts showed clinical signs of the respiratory disease sometimes described as 'mycoplasmosis catarrh', but most dead birds from which Mycoplasma spp. were isolated also had concomitant infections of various kinds. Although suggestive, the results of these investigations provide no clear evidence that Mycoplasma spp. are aetiologically involved in natural respiratory disease of pigeons. No conclusive satisfactory treatment was found for the elimination of mycoplasmas.

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This paper describes the telemetry system for the satellite UOSAT) designed and built in the Department of Electronic and Electrical Engineering of the University of Surrey. The function of the telemetry system is to encode outputs of sensors, located around the spacecraft, into specified data formats prior to transmission via downlink transmitters. In addition, information relating to the status sub-systems and data from on-board experiments require similar encoding. The basic philosophy of the telemetry system aims at providing a continuous and comprehensive surveillance of spacecraft systems for engineering purposes and a number of data formats to for different ground station facilities.