200 research outputs found

    Robotic-arm assisted versus conventional unicompartmental knee arthroplasty : exploratory secondary analysis of a Randomised Controlled Trial

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    Objectives: This study reports on a secondary exploratory analysis of the early clinical outcomes of an randomised clinical trial comparing Robotic-arm Assisted Uni-compartmental Knee Arthroplasty (UKA) for medial compartment osteoarthritis of the knee compared to Manual UKA performed using traditional surgical jigs. This follows reporting of primary outcomes of implant accuracy and gait analysis that showed significant advantages in the Robotic-arm assisted group.Methods139 patients were recruited from a single centre. Patients were randomised to receive either a manual UKA implanted with the aid of traditional surgical jigs, or a UKA implanted with the aid of a tactile guided Robotic-arm Assisted system. Outcome measures included: American Knee Society Score (AKSS), Oxford Knee Score (OKS), Forgotten Joint Score (FJS), Hospital Anxiety Depression (HAD) Scale, University of California at Los Angeles (UCLA) Activity Scale, SF-12, Pain Catastrophising Scale (PCS), Somatic Disease (Primary care evaluation of mental disorders [PRIME-MD] score), Pain Visual Analogue Scale (VAS), Analgesic use, Patient Satisfaction, complications relating to surgery, 90 day Pain diaries and the requirement for revision surgery.ResultsFrom day 1 post-operation through to week 8 post-operation the median pain scores for Robotic-arm Assisted group were 55.4% lower than those observed in the Manual surgery group (p = 0.040). A greater proportion of patients receiving Robotic-arm Assisted surgery improved their UCLA activity score.At 3 months post-operation, the Robotic-arm Assisted group had better AKSS scores (Robotic median 164 (Quarter 1 131, Quarter 3 178), Manual 143 (Quarter 1 132, Quarter 3 166)), although no difference was noted with the OKS.At 1 year post-operation, the observed differences with the AKSS had narrowed from 21 points to 7 points (p = 0.106) (Robotic median=171 (Quarter 1 153, Quarter 3 179), Manual median=164 (Quarter 1 144, Quarter 3 182 No difference was observed with the OKS, and almost half of each group reached the ceiling limit of the score (OKS > 43).The key factors associated with achieving excellent outcome on the AKSS were a pre-operative activity level > 5 on the UCLA activity score and use of Robotic-arm surgery. Factors associated with a poor outcome were manual surgery and pre-operative depression.Conclusions: Robotic-arm assisted surgery results in improved early pain scores and early function scores in some patient reported outcomes measures, but no difference was observed, at 1 year post operatively. Although improved results favoured the Robotic arm assisted group in active patients (i.e. UCLA > = 5), these do not withstand more stringent multiplicity adjustments

    Recent Progress in CuInS2 Thin-Film Solar Cell Research at NASA Glenn

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    The National Aeronautics and Space Administration (NASA) is interested in developing low-cost highly efficient solar cells on light-weight flexible substrates, which will ultimately lower the mass-specific power (W/kg) of the cell allowing extra payload for missions in space as well as cost reduction. In addition, thin film cells are anticipated to have greater resistance to radiation damage in space, prolonging their lifetime. The flexibility of the substrate has the added benefit of enabling roll-to-roll processing. The first major thin film solar cell was the "CdS solar cell" - a heterojunction between p-type CuxS and n-type CdS. The research on CdS cells started in the late 1950s and the efficiency in the laboratory was up to about 10 % in the 1980s. Today, three different thin film materials are leading the field. They include amorphous Si, CdTe, and Cu(In,Ga)Se2 (CIGS). The best thin film solar cell efficiency of 19.2 % was recently set by CIGS on glass. Typical module efficiencies, however, remain below 15 %

    Implementing textural features on GPUs for improved real-time pavement distress detection

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    The condition of municipal roads has deteriorated considerably in recent years, leading to large scale pavement distress such as cracks or potholes. In order to enable road maintenance, pavement distress should be timely detected. However, manual investigation, which is still the most widely applied approach toward pavement assessment, puts maintenance personnel at risk and is time-consuming. During the last decade, several efforts have been made to automatically assess the condition of the municipal roads without any human intervention. Vehicles are equipped with sensors and cameras in order to collect data related to pavement distress and record videos of the pavement surface. Yet, this data are usually not processed while driving, but instead it is recorded and later analyzed off-line. As a result, a vast amount of memory is required to store the data and the available memory may not be sufficient. To reduce the amount of saved data, the authors have previously proposed a graphics processing units (GPU)-enabled pavement distress detection approach based on the wavelet transform of pavement images. The GPU implementation enables pavement distress detection in real time. Although the method used in the approach provides very good results, the method can still be improved by incorporating pavement surface texture characteristics. This paper presents an implementation of textural features on GPUs for pavement distress detection. Textural features are based on gray-tone spatial dependencies in an image and characterize the image texture. To evaluate the computational efficiency of the GPU implementation, performance tests are carried out. The results show that the speedup achieved by implementing the textural features on the GPU is sufficient to enable real-time detection of pavement distress. In addition, classification results obtained by applying the approach on 16,601 pavement images are compared to the results without integrating textural features. There results demonstrate that an improvement of 27% is achieved by incorporating pavement surface texture characteristics

    Soil mobility of surface applied polyaromatic hydrocarbons in response to simulated rainfall

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    Polyaromatic hydrocarbons (PAHs) are emitted from a variety of sources and can accumulate on and within surface soil layers. To investigate the level of potential risk posed by surface contaminated soils, vertical soil column experiments were conducted to assess the mobility, when leached with simulated rainwater, of six selected PAHs (naphthalene, phenanthrene, fluoranthene, pyrene, benzo(e)pyrene and benzo(ghi)perylene) with contrasting hydrophobic characteristics and molecular weights/sizes. The only PAH found in the leachate within the experimental period of 26 days was naphthalene. The lack of migration of the other applied PAHs were consistent with their low mobilities within the soil columns which generally parallelled their log Koc values. Thus only 2.3% of fluoranthene, 1.8% of pyrene, 0.2% of benzo(e)pyrene and 0.4% of benzo(ghi)perylene were translocated below the surface layer. The PAH distributions in the soil columns followed decreasing power relationships with 90% reductions in the starting levels being shown to occur within a maximum average depth of 0.94 cm compared to an average starting depth of 0.5 cm. A simple predictive model identifies the extensive time periods, in excess of 10 years, required to mobilise 50% of the benzo(e)pyrene and benzo(ghi)perylene from the surface soil layer. Although this reduces to between 2 and 7 years for fluoranthene and pyrene, it is concluded that the possibility of surface applied PAHs reaching and contaminating a groundwater aquifer is unlikely

    A ‘Baby GDA’: Norwich’s Airspace during the Second World War

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    Throughout the Second World War, the Luftwaffe attacked Norwich on various occasions. The impact this had on the city was recorded visually on the ‘Norwich Bomb Map’. This cartographic depiction, however, only records a single ‘horizontal’ component of the aerial ‘battlescape’. In reality, the aerial battlefield comprised a combination of Norwich’s air defences and the flightpaths of the Luftwaffe bombers, which existed in three-dimensional space. As other scholars have developed methodologies for reconstructing anti-aircraft ‘fire domes’, this article will combine these concepts with a new approach that reconstructs historic flightpaths to give a three-dimensional overview of Norwich’s ‘Gun Defended Area’. By examining all components of Norwich’s airspace, this article will demonstrate the importance of considering the vertical component of a battlescape
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