Ultrasonographic-based predictive factors influencing successful return to racing after superficial digital flexor tendon injuries in flat racehorses: a retrospective cohort study in 469 Thoroughbred racehorses in Hong Kong

Background: Superficial digital flexor tendon (SDFT) injury is an important health and welfare concern in racehorses. It is generally diagnosed with ultrasonography, predictive ultrasonographic features have not been reported. Objectives: To determine ultrasonographic features of forelimb SDFT injury at initial presentation in Thoroughbred racehorses, that could predict a successful return to racing (completing > or = 5 races). Study Design: Retrospective cohort study. Methods: Digitised ultrasonographic images of 469 horses with forelimb SDFT injuries from the Hong Kong Jockey Club (2003-2014) were evaluated, using a previously validated ultrasonographic scoring system. Six ultrasonographic parameters were evaluated (type and extent of the injury, location, echogenicity, cross-sectional area and longitudinal fiber pattern of the maximal injury zone (MIZ)), as well as horse signalment, retirement date and number of races before and after injury. Data was analysed by generalized linear regression with significance at P<0.05. Results: Cases were divided in two groups: 1) For cases of SDFT tendonitis with core lesions, cross-sectional area at the MIZ was the most significant factor determining a successful return to racing (p=0.03). If the lesion was or > or = 50% this decreased to 11-16%. 2) For cases of SDFT tendonitis without a core lesion, longitudinal fiber pattern at the MIZ best predicted a successful return to racing (P=0.002); if the affected longitudinal fiber pattern was or = 75% this decreased to 14%. Main Limitations: Prognostic information may not be applicable to other breeds/disciplines. Conclusions: This is the first study to describe ultrasonographic features of forelimb SDFT injuries at initial presentation that were predictive of successful return to racing. The outcomes will assist with early, evidence-based decisions on prognosis in Thoroughbred racehorses

Ultrasonographic-based predictive factors influencing successful return to racing after superficial digital flexor tendon injuries in flat racehorses: a retrospective cohort study in 469 Thoroughbred racehorses in Hong Kong

Background: Superficial digital flexor tendon (SDFT) injury is an important health and welfare concern in racehorses. It is generally diagnosed with ultrasonography, predictive ultrasonographic features have not been reported. Objectives: To determine ultrasonographic features of forelimb SDFT injury at initial presentation in Thoroughbred racehorses, that could predict a successful return to racing (completing > or = 5 races). Study Design: Retrospective cohort study. Methods: Digitised ultrasonographic images of 469 horses with forelimb SDFT injuries from the Hong Kong Jockey Club (2003-2014) were evaluated, using a previously validated ultrasonographic scoring system. Six ultrasonographic parameters were evaluated (type and extent of the injury, location, echogenicity, cross-sectional area and longitudinal fiber pattern of the maximal injury zone (MIZ)), as well as horse signalment, retirement date and number of races before and after injury. Data was analysed by generalized linear regression with significance at P<0.05. Results: Cases were divided in two groups: 1) For cases of SDFT tendonitis with core lesions, cross-sectional area at the MIZ was the most significant factor determining a successful return to racing (p=0.03). If the lesion was or > or = 50% this decreased to 11-16%. 2) For cases of SDFT tendonitis without a core lesion, longitudinal fiber pattern at the MIZ best predicted a successful return to racing (P=0.002); if the affected longitudinal fiber pattern was or = 75% this decreased to 14%. Main Limitations: Prognostic information may not be applicable to other breeds/disciplines. Conclusions: This is the first study to describe ultrasonographic features of forelimb SDFT injuries at initial presentation that were predictive of successful return to racing. The outcomes will assist with early, evidence-based decisions on prognosis in Thoroughbred racehorses

Single-loop all-pass-filter-based active damping for VSCs with LCL filters connected to the grid

LCL filters are commonly used to connect Voltage Sourced Converters (VSCs) to the grid. This type of filters are cheaper than a single inductor, but they can generate resonance problems if no active or passive damping method is used. Active damping methods are becoming popular in the literature because they improve efficiency, but they are sometimes difficult to implement and additional measurements are required. This paper proposes a method to provide active damping for VSCs connected to the grid that is based on making zero the openloop phase at the resonance frequency. It will shown that this strategy provides adequate damping of oscillations and that it can be achieved in two different ways: at the design stage (if the design constraints make it possible) or with an all-pass filter in series with the current controller. All the proposed control algorithms are verified by simulation and in a 15 kW prototype of a three-phase VSC connected to the grid with an LCL filter

Design of modular, CFRP-encased electrical power systems for more-electric aircraft applications

Decarbonisation of aviation is directly supported by the twin trends of electrification of aircraft, and use of light-weight, carbon fibre reinforced polymer (CFRP) aircraft structures. The concept of creating a modularised electrical power system (EPS), with EPS equipment encased in CFRP opens up new design opportunities for electrification of aircraft systems; reduced weight and volume, reduced time out-of-service due to maintenance. Such systems necessitate an understanding of how electrical and structural systems interact, and the design boundary between the CFRP providing combined electrical and structural functionality, versus CFRP with a purely structural functionality, with a separate electrical system encased in CFRP. A power electronic converter (PEC) is an enabling technology for the more-electric aircraft EPS. The paper identifies the key design interdependencies, trades and integrated systems design levers for design of a CFRP casing for a PEC module through a conceptual case study. This includes the capture of high and low frequency electrical functionality, thermal management requirements, and their interdependencies with the topology and functional role of the PEC and the wider EPS architecture. This knowledge is combined to present a design methodology for the design of composite casings for PEC in modularised, on-board electrical power systems

Comparison of phase-leg circuits for cryogenic operation in the all-electric aircraft

Commercial all-electric aircraft are projected to be flying as early as 2035, where hydrogen is selected to supply fuel and coolant. The cryogenic aircraft's powertrain includes the turbines, generators, power electronics and fan motors. As most of the powertrain is located at cryogenic temperature, it is preferable to co-locate the power electronics in the same region to reduce the engineering system's complexity. Silicon super-junction MOSFETs are known for their high efficiency, thus lower cooling requirements at cryogenic temperature. However, in phase-leg circuits, the behaviour of the MOSFET's intrinsic diode, and its output capacitance are challenging. These issues can be addressed by using the MOSFET with ancillary power devices to realise diode deactivation. This paper compares different permutations of intrinsic diode deactivation devices at room temperature and cryogenic temperature. The paper presents a demonstrator phase-leg built with different ancillary power devices. It is operated from a DC voltage of 270 V, and supplies a phase current of up to 10 A

Electrical and Thermal Effects of Fault Currents in Aircraft Electrical Power Systems with Composite Aerostructures

The upwards trend for the use of electrical power on state of the art aircraft is resulting in significant change to the design of power system architectures and protection systems for these platforms. There is a pull from the aerospace industry to integrate the electrical power system with the aircraft’s structural materials to form an embedded system, reducing the need for bulky cable harnesses. This directly impacts the fault response for ground faults and ultimately the development of appropriate protection systems. Such structural materials include composites such as carbon fibre reinforced polymer (CFRP). This paper presents the experimental capture and analysis of the response of CFRP to electrical fault current, which indicates the need for two distinct sets of electrical ground fault detection criteria for low and high resistance faults and identifies the threshold resistance for this distinction. By extrapolating these results to develop models of CFRP for use in transient simulation studies, the key electrical fault detection thresholds for speed, selectivity and sensitivity for a DC system rail to ground fault through CFRP are identified. This provides the first set of key factors for electrical fault detection through CFRP, providing a platform for the design of fully integrated structural and electrical power systems, with appropriate electrical protection systems

A Feature-Driven Active Framework for Ultrasound-Based Brain Shift Compensation

A reliable Ultrasound (US)-to-US registration method to compensate for brain shift would substantially improve Image-Guided Neurological Surgery. Developing such a registration method is very challenging, due to factors such as missing correspondence in images, the complexity of brain pathology and the demand for fast computation. We propose a novel feature-driven active framework. Here, landmarks and their displacement are first estimated from a pair of US images using corresponding local image features. Subsequently, a Gaussian Process (GP) model is used to interpolate a dense deformation field from the sparse landmarks. Kernels of the GP are estimated by using variograms and a discrete grid search method. If necessary, the user can actively add new landmarks based on the image context and visualization of the uncertainty measure provided by the GP to further improve the result. We retrospectively demonstrate our registration framework as a robust and accurate brain shift compensation solution on clinical data acquired during neurosurgery

The Inclusiveness and Emptiness of <i>Gong Qi</i>: A Non-Anglophone Perspective on Ethics from a Sino-Japanese Corporation

This article introduces a non-Anglophone concept of gong qi(communal vessel, 公器) as a metaphor for ‘corporation’. It contributes an endogenous perspective from a Sino-Japanese organizational context that enriches mainstream business ethics literature, otherwise heavily reliant on Western traditions. We translate the multi-layered meanings of gong qi based on analysis of its ideograms, its references into classical philosophies, and contemporary application in this Japanese multinational corporation in China. Gong qi contributes a perspective that sees a corporation as an inclusive and virtuous social entity, and also addresses the elusive, implicit, and forever evolving nature of organizational life that is rarely noticed. We propose gong qi can be applied in other organizations and wider cultural contexts to show a new way of seeing and understanding business ethics and organization. Rather than considering virtue as a list of definable individual qualities, we suggest that the metaphor of gong qi reveals how virtue can be experienced as indeterminate, yet immanently present, like the substance of emptiness. This, then allows us to see the virtue of immanence, the beauty of implicitness, and hence, the efficacy of gong qi