A Robotic Experimental Setup with a Stewart Platform to Emulate Underwater Vehicle-Manipulator Systems.

This study presents an experimental robotic setup with a Stewart platform and a robot manipulator to emulate an underwater vehicle-manipulator system (UVMS). This hardware-based emulator setup consists of a KUKA IIWA14 robotic manipulator mounted on a parallel manipulator, known as Stewart Platform, and a force/torque sensor attached to the end-effector of the robotic arm interacting with a pipe. In this setup, we use realistic underwater vehicle movements either communicated to a system in real-time through 4G routers or recorded in advance in a water tank environment. In addition, we simulate both the water current impact on vehicle movement and dynamic coupling effects between the vehicle and manipulator in a Gazebo-based software simulator and transfer these to the physical robotic experimental setup. Such a complete setup is useful to study the control techniques to be applied on the underwater robotic systems in a dry lab environment and allows us to carry out fast and numerous experiments, circumventing the difficulties with performing similar experiments and data collection with actual underwater vehicles in water tanks. Exemplary controller development studies are carried out for contact management of the UVMS using the experimental setup.

Application of Adaptive and Switching Control for Contact Maintenance of a Robotic Vehicle-Manipulator System for Underwater Asset Inspection.

The aim of this study is to design an adaptive controller for the hard contact interaction problem of underwater vehicle-manipulator systems (UVMS) to realize asset inspection through physical interaction. The proposed approach consists of a force and position controller in the operational space of the end effector of the robot manipulator mounted on an underwater vehicle. The force tracking algorithm keeps the end effector perpendicular to the unknown surface of the asset and the position tracking algorithm makes it follow a desired trajectory on the surface. The challenging problem in such a system is to maintain the end effector of the manipulator in continuous and stable contact with the unknown surface in the presence of disturbances and reaction forces that constantly move the floating robot base in an unexpected manner. The main contribution of the proposed controller is the development of the adaptive force tracking control algorithm based on switching actions between contact and noncontact states. When the end effector loses contact with the surface, a velocity feed-forward augmented impedance controller is activated to rapidly regain contact interaction by generating a desired position profile whose speed is adjusted depending on the time and the point where the contact was lost. Once the contact interaction is reestablished, a dynamic adaptive damping-based admittance controller is operated for fast adaptation and continuous stable force tracking. To validate the proposed controller, we conducted experiments with a land robotic setup composed of a 6 degrees of freedom (DOF) Stewart Platform imitating an underwater vehicle and a 7 DOF KUKA IIWA robotic arm imitating the underwater robot manipulator attached to the vehicle. The proposed scheme significantly increases the contact time under realistic disturbances, in comparison to our former controllers without an adaptive control scheme. We have demonstrated the superior performance of the current controller with experiments and quantified measures.

A genome-wide linkage study in families with major depression and co-morbid unexplained swelling.

Major depressive disorder (MDD) is a common heritable condition. The diversity of the phenotype coupled with aetiological and genetic heterogeneity present formidable obstacles in the search for causative genetic loci. Studies of large families with many affected individuals, and the selection of well-defined clinical subgroups of depression, are two ways to reduce this complexity. Unexplained swelling symptoms (USS) are common in women and many patients give a strong personal and family history of depression. Co-morbid depression and swelling symptoms define a useful sub-phenotype for investigating genetic factors in depression. We have completed a genome-wide linkage analysis using 371 microsatellite markers in four families where MDD is co-morbid with USS. Of 47 affected individuals, 28 had both MDD and unexplained swelling, 11 had symptoms of swelling alone, and 8 had MDD alone. Parametric marker-specific analysis identified one suggestive locus, D8S260 (LOD = 2.02) and non-parametric multipoint variance component analysis identified a region on 7p (LOD = 2.10). A 47 cM suggestive linkage region on chromosome 14q (identified by both parametric and non-parametric methods) was identified and investigated further with fine-mapping markers but the evidence for linkage to this region decreased with increased marker information content.

Meat consumption reduces the risk of nutritional rickets and osteomalacia.

Endogenous vitamin D deficiency (low serum 25(OH)D3) is a necessary but insufficient requirement for the genesis of vitamin D-deficiency rickets and osteomalacia. The magnitude of the independent contributions of dietary factors to rachitic and osteomalacic risk remains uncertain. We reanalysed two weighed dietary surveys of sixty-two cases of rickets and osteomalacia and 113 normal women and children. The independent associations of four dietary variables (vitamin D, Ca, fibre and meat intakes) and daylight outdoor exposure with rachitic and osteomalacic relative risk were estimated by multivariate logistic regression. Meat and fibre intakes showed significant negative and positive associations respectively with rachitic and osteomalacic relative risk (RR; zero meat intake: RR 29.8 (95 % CI 4.96, 181), P<0.001; fibre intake: RR 1.53 (95 % CI 1.01, 2.32), P=0.043). The negative association of meat intakes with rachitic and osteomalacic relative risk was curvilinear; relative risk did not fall further at meat intakes above 60 g daily. Daylight outdoor exposure showed a significant negative association with combined relative risk (RR 0.33 (95 % CI 0.17, 0.66), P<0.001). Operation of the meat and fibre risk factors was related to sex, age and dietary pattern (omnivore/lactovegetarian), mainly determined by religious affiliation. The mechanism by which meat reduces rachitic and osteomalacic risk is uncertain and appears independent of revised estimates of meat vitamin D content. The meat content of the omnivore Western diet may explain its high degree of protection against nutritional rickets and osteomalacia from infancy to old age in the presence of endogenous vitamin D deficiency.

UK Food Standards Agency Optimal Nutrition Status Workshop: environmental factors that affect bone health throughout life.

The UK Food Standards Agency (FSA) convened a group of expert scientists to discuss and review UK FSA- and Department of Health-funded research on diet and bone health. This research focused on the lifestyle factors that are amenable to change and may significantly affect bone health and the risk of osteoporotic fracture. The potential benefits of fruits and vegetables, meat, Ca, vitamins D and K and phyto-oestrogens were presented and discussed. Other lifestyle factors were also discussed, particularly the effect of physical activity and possible gene-nutrient interactions affecting bone health.

Downsizing of acute inpatient beds associated with private finance initiative: Scotland's case study.

OBJECTIVES: To evaluate whether the projected 24% reduction in acute bed numbers in Lothian hospitals, which formed part of the private finance initiative (PFI) plans for the replacement Royal Infirmary of Edinburgh, is being compensated for by improvements in efficiency and greater use of community facilities, and to ascertain whether there is an independent PFI effect by comparing clinical activity and performance in acute specialties in Lothian hospitals with other NHS hospitals in Scotland. DESIGN: Comparison of projected and actual trends in acute bed capacity and inpatient and day case admissions in the first five years (1995-6 to 2000-1) of Lothian Health Board's integrated healthcare plan. Population study of trends in bed rate, hospital activity, length of stay, and throughput in Lothian hospitals compared with the rest of Scotland from 1990-1 to 2000-1. MAIN OUTCOME MEASURES: Staffed bed rates, admission rates, mean lengths of stay, occupancy, and throughput in four adult acute specialty groups in 1990-1, 1995-6, and 2000-1. RESULTS: By 2000-1, rates for inpatient admission in all acute, medical, surgical, and intensive therapy specialties in Lothian hospitals were respectively 20%, 6%, 28%, and 38% below those in the rest of Scotland. Day case rates in all acute and acute surgical specialties were 13% and 33% lower. The proportion of delayed discharges in staffed acute and post-acute NHS beds in Lothian hospitals exceeded the Scottish average (15% and 12% respectively; P<0.001). CONCLUSION: The planning targets and increase in clinical activity in acute specialties in Lothian hospitals associated with PFI had not been achieved by 2000-1. The effect on clinical activity has been a steeper decline in the number of acute beds and rates of admission in Lothian hospitals compared with the rest of Scotland between 1995-6 and 2000-1.