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OBJECTIVES Accurate visualization of dental root canals is vital for the correct diagnosis and subsequent treatment. This work assesses the improvement of a dedicated new coil for dental magnetic resonance imaging (MRI) in comparison to conventional ones in terms of signal-to-noise ratio (SNR) and visibility. MATERIALS AND METHODS A newly developed intraoral flexible coil was used to display dental roots with MRI, and it provides improved sensitivity with a loop design and size adjusted to a single tooth anatomy. Ex vivo and in vivo measurements were performed on a 3 T clinical MR system, and results were compared with conventional head and surface coil images. Additional comparison was performed with a modified fast spin echo sequence and a constructive interference in steady-state sequence. RESULTS Ex vivo, an SNR gain of 6.3 could be achieved with the intraoral flexible coil setup, and higher visibility down to 200 μm was possible, whereas the external loop coil is limited to 400 μm. In vivo measurements in a volunteer resulted in an SNR gain of up to 4.5 with an improved delineation of the root canals, especially for the branch tissue splitting of the mesial root canal into mesial-buccal and mesial-lingual. CONCLUSIONS In summary, we showed the feasibility of implementing a wireless coil approach with readily available dental practice materials for sealing and placement. Highly improved MRI scans can be acquired within clinically feasible scan times, and this might provide additional medical findings to supplement available x-ray images.

Objective : The present study was aimed to analyse the efficacy of specs loop, a newly designed closing loop.Materials and Methods : A finite element maxillary model for en-masse anterior retractio...

Objectives The Polaris™ loop ureteric stent reduces the severity of stent discomfort by minimising stent material in the bladder. Early impact of ureteral stenting on quality of life (QoL) within 1 week remains unclear. The usefulness of the patient-administered ureteral stent symptoms questionnaire (USSQ) during this period of stent insertion was assessed. In this pilot single-blinded prospective randomised study, we investigate 1) the presence of early (within the 1st week) stent discomfort via the visual analog scale (VAS); 2) determine the QoL of the loop stent against conventional stent. Methods Forty adults requiring retrograde unilateral ureteral stent placements were enrolled. Patients with single ureteric stone or benign stricture were selected. Patients were randomised in 1:1 ratio to the loop and pigtail arm. The USSQ was administered before placement (baseline), USSQ and VAS were administered on Day 3, 7, and 14. Results There were no significant differences between the USSQ scores. Median pain scores on Day 3 were lower in the loop stent group (2.9 vs. 4.0, p=0.047). There was a significant reduction in pain from Day 3–7 (0 vs. −1, p=0.016) in the pigtail group. Conclusions Our results suggest that peak stent discomfort occurs but resolves quickly within 1 week of post-stent insertion. The loop stent offers a better pain profile compared with conventional stents at Day 3 but no difference in QoL. The loop stent reduces early pain experience post-stent insertion and may have a role in the care of patients who experience significant stent discomfort previously.

The advantages of the all-fiber optical current transformer include but are not limited to being small in size, having no magnetic saturation, exhibiting high measurement accuracy, and boasting strong electromagnetic interference resistance. However, the high cost of the all-fiber optical transformer limits its promotion and application in engineering. This paper proposes a design scheme of an independent double acquisition loop for the all-fiber optical current transformer based on the single optical path. Firstly, based on the closed-loop control mode and open-loop control mode, the two- channel sampling signal demand for relay protection, and the independent dual-acquisition loop design scheme of the all-fiber optical current transformer are proposed. Secondly, the reliability and economic feasibility of the scheme are demonstrated by an analysis of system failure and cost. The results show that the scheme can actualize the acquisition function of two independent all-fiber optical current transformer products on a single all-fiber current transformer in an integrated manner, which greatly reduces the cost of the all-fiber optical current transformer in engineering applications. Keywords: All-fiber optical current transformer, Acquisition circuit, Reliability

Batteries are one of the most used and viable energy storage systems that we use nowadays due to its high efficiency and low environmental impact. Today, batteries are the most important elements in the transportation industry and the electronic development field. To maximize battery performance and extend battery life, it is important to have a Battery fuel gauge (BFG) that accurately tracks its State of Charge (SOC), that consequently helps estimate the equivalent circuit model (ECM), and have its parameters estimated by the battery management system. Without accurate ECM modeling and parameter estimation it is not possible to have an accurate estimation of the State of Charge (SOC) of the battery. An analysis of the literature indicates that there is still room for improvement in SOC estimation and parameter estimation.

Background Isolation gowns are recommended to protect healthcare personnel, patients, and visitors from transfer of microorganisms and body fluids in patient isolation situations. Standards provide limited information about barrier performance of isolation gowns for possible exposure scenarios. One of the most vulnerable areas of the personal protective equipment ensemble is considered the glove-gown interface. However, current isolation gown classification standards do not consider the interface regions of the personal protective equipment system while assessing the level of protection. The purpose of this study was to quantitatively evaluate the fluid leakage through the glove-gown interface by simulating exposures and healthcare personnel arm movements in patient care for isolation settings. Methods We tested fluid leakage of two examination gloves with different cuff lengths and seven isolation gown models designed with varying levels of barrier resistance and multiple cuff types. Results Our results demonstrated that leakage through the glove-gown interface depends on multiple factors, including glove cuff length and gown cuff design. Gowns with the thumb loop design provided better protection than the elastic cuff design, and the elastic cuff design provided better protection compared to the knit cuff design for a given AAMI PB70 level. More importantly, a substantial penetration through gown fabrics was observed. Conclusions This research identifies a need to develop a standardized method to evaluate leakage at the glove-gown interface to improve worker protection.

5 pags., 4 figs., Loops are key components of protein structures, involved in many biological functions. Due to their conformational variability, the structural investigation of loops is a difficult topic, requiring a combination of experimental and computational methods. This paper provides a brief overview of current computational approaches to flexible loop modeling, and presents the main ingredients of the most standard protocols. Despite great progress in recent years, accurately modeling the conformational variability of long flexible loops remains a challenging problem. Future advances in this field will likely come from a tight coupling of experimental and computational techniques, which would enable a better understanding of the relationships between loop sequence, structural flexibility, and functional roles. In fine, accurate loop modeling will open the road to loop design problems of interest for applications in biomedicine and biotechnology., This work has been supported by the French National Research Agency (ANR) through grant ANR-19-PI3A-0004 and by the Spanish grants BFU2016-76220-P and PID2019-109041 GB-C21 (AEI,10.13039/501100011033).

This article presents a design and commissioning of a multiphase flow loop, which was developed for scrutinizing the partial phase separation characteristics of pipe Tees. Its length is 9m and its primary diameter is 0.078m (3 inches). For the ease of modification, its design was kept modular, so that it could be used for testing various other pipe profiles. To validate this flow loop, the separation of a stratified-wavy flow was tested in a regular diameter ratio pipe Tee, and the gathered results were compared with previously published data. A good agreement was observed between the two data sources, which suggests that this flow loop is suitable for a further experimentation.

Effective Steam Assisted Gravity Drainage (SAGD) operation relies on subcool management to reduce the risk of steam breakthrough. Monitoring of several parameters is performed to assure uniform development of steam chamber and heating of reservoir. This paper discusses the application of Distributed Acoustic Sensing (DAS), a monitoring platform to achieve reliable reservoir and wellbore surveillance in SAGD projects. In this study, a comprehensive review of DAS deployment in oil and gas industry was performed including vertical seismic profiling, hydraulic fracturing, well/pipe integrity and flow profiling applications. Then, SAGD flow monitoring was investigated in detail. To utilize DAS in SAGD projects, knowing completion designs are necessary. Therefore, various SAGD completion designs and corresponding flow regimes were discussed as well. Finally, four flow loop designs were proposed to accurately simulate the complex wellbore hydraulics of the SAGD producer using DAS recordings. This work started with an overview of DAS systems in downhole monitoring including real time high resolution vertical seismic profiling, hydraulic fracturing characterization and optimization, well and pipe integrity, leak detection and assessing completion effectiveness. Then, flow profiling including flow rate, flow fractions and flow regimes determinations using DAS were discussed with focus on SAGD monitoring. Completion designs directly impact on SAGD monitoring and DAS recordings, more specifically on flow regimes inside the tubing and annulus. Therefore, various completion designs with their tubing and screen sizes were presented and corresponding flow regimes were determined in both tubing and annulus. It was observed that flow regimes vary with type of completion design, liquid flow rate, steam breakthrough locations and tubing/screen sizes. Eventually, four flow loop designs were proposed based on the discussions for future DAS application. This paper discusses existing completion designs and possible flow regimes in SAGD projects. Consequently, novel designed flow loops are introduced for DAS deployment to better understand the complex wellbore hydraulic of the well and measure the key parameters in optimizing the production operation. This study is a design stage for future quantitative measuring of flow profiling using DAS systems.

This paper presents a cooperative differential game theory approach to designing a consensus-based formation control strategy for multi-UAVs (agents). The consensus-based formation control problem is defined as a tracking task where the states of each agent must follow a given reference. Position states are given as fixed offsets between each agent to achieve a formation, whilst velocity and attitude should be identical amongst agents to archive consensus. Using a cooperative game theory based approach, each agent acts to reduce the weighted team cost to reach consensus. The control strategy design is based on open-loop design, closed-loop design, and a semi-open-loop design concept to better account for different hardware configurations. The control approach is validated via simulations to show how cooperative game theory based consensus formation control can outperform non-cooperative game theory control and general optimal control with respect to reducing formation deviation. The semi-open loop design is proven to be suitable for practical applications.

This paper studies the dynamic interactions between the AC grids and the DC system. In this work, we focus on MMC-HVDC links interconnecting offshore wind farms and AC systems. The onshore converter is controlled in DC-voltage control mode on the DC side and in grid-forming on the AC side. The authors show the importance of DC-voltage loop design when controlling the MMC in grid-forming mode and its consequences on the MMC internal energy. In the conclusion, some recommendations are made regarding different potential solutions for supporting the DC voltage.

Mechanical circulatory support (MCS) devices continue to be hampered by thrombotic adverse events (AEs), a consequence of device-imparted supraphysiologic shear stresses, leading to shear-mediated platelet activation (SMPA). In advancing MCS devices from design to clinical use, in vitro circulatory loops containing the device under development and testing are utilized as a means of assessing device thrombogenicity. Physical characteristics of these test circulatory loops may also contribute to inadvertent platelet activation through imparted shear stress, adding inadvertent error in evaluating MCS device thrombogenicity. While investigators normally control for the effect of a loop, inadvertent addition of what are considered innocuous connectors may impact test results. Here, we tested the effect of common, additive components of in vitro circulatory test loops, that is, connectors and loop geometry, as to their additive contribution to shear stress via both in silico and in vitro models. A series of test circulatory loops containing a ventricular assist device (VAD) with differing constituent components, were established in silico including: loops with 0~5 Luer connectors, a loop with a T-connector creating 90° angulation, and a loop with 90° angulation. Computational fluid dynamics (CFD) simulations were performed using a k - ω shear stress transport turbulence model to platelet activation index (PAI) based on a power law model. VAD-operated loops replicating in silico designs were assembled in vitro and gel-filtered human platelets were recirculated within (1 hour) and SMPA was determined. CFD simulations demonstrated high shear being introduced at non-smooth regions such as edge-connector boundaries, tubing, and at Luer holes. Noticeable peaks' shifts of scalar shear stress (sss) distributions toward high shear-region existed with increasing loop complexity. Platelet activation also increased with increasing shear exposure time, being statistically higher when platelets were exposed to connector-employed loop designs. The extent of platelet activation in vitro could be successfully predicted by CFD simulations. Loops employing additional components (non-physiological flow pattern connectors) resulted in higher PAI. Loops with more components (5-connector loop and 90° T-connector) showed 63% and 128% higher platelet activation levels, respectively, versus those with fewer (0-connector (P = .023) and a 90° heat-bend loop (P = .0041). Our results underscore the importance of careful consideration of all component elements, and suggest the need for standardization in designing in vitro circulatory loops for MCS device evaluation to avoid inadvertent additive SMPA during device evaluation, confounding overall results. Specifically, we caution on the use and inadvertent introduction of additional connectors, ports, and other shear-generating elements which introduce artifact, clouding primary device evaluation via introduction of additive SMPA.

The subject of this chapter is a method of evaluating costs and performance of container ships as means of transport in the main part of the intermodal transport chain for ISO containers. The rational is the continuous development in the size of container ships, the infrastructure development to cater for them and the strong variations in bunker prices over the past years. Furthermore, the complete transport chain development with pre- and on-carriage cannot be seen as risk-free. The method described will make clear that the factors for success or lack of success for large container ships can be found almost exclusively in the ports and their hinterland infrastructure in combination with the general loop design.

The chapter presents the results of experimental and numerical studies of the impact of the design of selected zones of a hybrid fluidized-bed apparatus on its hydrodynamic properties. In particular experimental tests were carried out to characterize the hydrodynamics of the bottom zone and of the degassing zone. The analysis of liquid flow through these zones was performed using tracer experiments done with the stimulus-response method to determine the presence of local liquid circulation that could lead to local oxygen deficiency in the apparatus (dead zones) or privileged flow channels. In addition, CFD simulations of the liquid flow through the bottom zone of the apparatus were carried out assuming different design solutions for this zone.

Despite good initial pullout strength, it is unclear whether adjustable button (AB) devices for anterior cruciate ligament (ACL) soft-tissue graft fixation, which are based on the Chinese finger trap technique, resist cyclic loading. Furthermore, they have never been tested in a cyclic protocol including complete unloading. It was hypothesized, that the displacement of AB devices with the Chinese finger trap technique would be greater than that of continuous suture loop devices and other available AB mechanisms in a cyclic loading with complete unloading protocol. ACL reconstruction was performed in a porcine knee model using three different types of cortical fixation devices: two different AB devices that use the Chinese finger trap design, one AB device that uses a locked suture loop mechanism and two different continuous loop devices as control groups (n = 40). Specimens were mounted in a material-testing machine (Instron Inc.) that permitted 2500 loading and complete unloading cycles to a maximum of 250 N, as well as continuous elongation recording. A one-way ANOVA was performed for statistical analysis. The displacement of ABs with a Chinese finger trap loop (mean 8.1; SD 1.5 mm and mean 6.1; SD 1.4 mm) was significantly greater than that of AB with a locked suture loop (mean 4.7; SD 1.0 mm; p

Background/Purpose The application of an appropriate force system is indispensable for successful orthodontic treatments. Second-order moment control is especially important in many clinical situations, so we developed a new force system composed of a straight orthodontic wire and two crimpable hooks of different lengths to produce the second-order moment. The objective of this study was to evaluate this new force system and determine an optimum condition that could be used in clinics. Methods We built a premolar extraction model with two teeth according to the concept of a modified orthodontic simulator. This system was activated by applying contractile force from two hooks that generated second-order moment and force. The experimental device incorporated two sensors, and forces and moments were measured along six axes. We changed the contractile force and hook length to elucidate their effects. Three types of commercial wires were tested. Results The second-order moment was greater on the longer hook side of the model. Vertical force balanced the difference in moments between the two teeth. Greater contractile force generated a greater second-order moment, which reached a limit of 150 g. Excessive contractile force induced more undesired reactions in the other direction. Longer hooks induced greater moment generation, reaching their limit at 10 mm in length. Conclusion The system acted similar to an off-center V-bend and can be applied in clinical practice as an unconventional loop design. We suggest that this force system has the potential for second-order moment control in clinical applications.

In this study, we evaluated a new data-driven approach for designing a dual-rate cascade control system. A dual-rate cascade control system consists of inner and outer loops, where the update interval of the inner loop controller is shorter than that of the outer controller. In the proposed method, fictitious reference iterative tuning is used to optimize the controller parameters in the inner and outer loops. Hence, the controller parameters are designed using only the control data, and no modeling procedure is needed. The controller parameter for the inner loop is optimized first, and then the outer loop parameter is optimized. Because the inner loop is updated faster than the outer loop in the dual-rate system, the control performance of the proposed dual-rate design is superior to that of conventional single-rate systems. The effectiveness of the proposed method was demonstrated using numerical examples.

Мета: У статті розглянуто проблеми проектування робастних високоточних систем визначення просторової орієнтації, які можуть використовуватися у навігації морських рухомих об’єктів. Головною метою є створення оптимізаційних процедур проектування навігаційних та стабілізаційних контурів багаторежимної платформної системи. Оптимізаційна процедура проектування навігаційного контуру заснована на параметричній робастній H2/H∞-оптимізації. Оптимізаційна процедура проектування контуру стабілізації заснована на робастному структурному H∞-синтезі. Методи дослідження: Для розв’язання даної проблеми було використано теорію робастних систем управління та оптимізаційні методи. Результати: Представлено кінематичну схему системи визначення просторової орієнтації. Наданий алгоритм параметричної оптимізації з урахуванням особливостей досліджуваної системи. Визначено закони управління навігаційних контурів на підставі оптимізаційної процедури, що забезпечує компроміс між точністю та робастністю системи. Розроблено робастний регулятор стабілізаційного контуру на підставі методу змішаної чутливості. Виконано імітаційне моделювання процесів навігації та стабілізації. Висновки: Представлені результати підтверджують ефективність запропонованих процедур, які можуть бути корисними для проектування навігаційних систем рухомих об’єктів.

The interaction between the substructure and its surrounding soil is a crucial consideration in structural health monitoring. In locations with seismic activity, many structures are susceptible to damage or failure due to soil liquefaction. Determining the horizontal stresses in soil before and during cyclic loading, which is a fundamental challenge in geotechnical engineering, has significant consequences on interpreting liquefaction susceptibility and predicting foundation response to earthquake loading. Measuring this value will help verify or modify previous assumptions made, and correct values can be incorporated in engineering calculations. The applicability of various existing sensing devices and concepts for measuring horizontal stresses in soil are investigated. Four commercially available pressure transducer sensor systems are evaluated when buried within a soil specimen. The evaluation of results showed that none of the sensors functioned well. Major limiting factors included hysteresis and nonlinearity in results, unrepeatability of tests, and placement of the sensor within the sample. More technologically advanced sensor concepts, such as an active control loop design or active expanding diaphragm type sensors seem inevitable for measuring horizontal stresses in soil.

In this paper, a three-dimensional partial integrated guidance and control law for the supersonic missile impacting the surface target is proposed. In the guidance loop design, a reduced-order extended state observer is integrated with feedback linearization and the pure proportional navigation law to eliminate the effects of the unknown target kinematics and the dynamic coupling between the vertical and horizontal planes. Considering the autopilot lag, two guidance schemes with different observer inputs are compared using the adjoint and frequency domain analyses. For the control loop, the angular velocity feedback is performed first for the pitch and yaw channels as conventionally done in practice, and then first-order linear active disturbance rejection control is designed for the damping-enhanced plant to deal with the fast time-varying, uncertain aerodynamics and the strong coupling effects among the three channels. Both the attitude angle and the acceleration control can be designed in a unified framework. Finally, a three-dimensional engagement scenario is performed using a six-degree-of-freedom supersonic vehicle model, and extensive simulations are carried out to validate the robustness and the high guidance precision of the proposed method.

Two implementations of transverse electromagnetic (TEM) horns are researched for wideband receiving (RX) and transmitting (TX) applications. Both configurations are flush-mountable and inspired by a combined TEM horn/loop design. For RX application, a 46:1 bandwidth antenna recessed in an absorptive cavity is developed having in mind requirements of an amplitude-only direction finding antenna subsystem. For TX operation, an integration approach is proposed to assimilate the antenna with a lossless cavity and eliminate excitation of cavity modes that may degrade its performance. This is enabled by the realization of a compact, high-power, and flush-mountable TEM horn array. Theory and experiments validate designs robustness and show good performance in both cases.

This paper presents the development made around the SeaBot, a new low-cost profiling float design for shallow water. We introduce a simplified dynamical model of the float and propose a state feedback depth controller coupled with an Extended Kalman Filter (EKF) to estimate model parameters. We show experimental results of the depth control that validate the model and the controller. We finally propose a loop design method to build low-cost floats by highlighting key design choices along with design rules.

Aim: Resistance to sliding between bracket and wire is present, in a different magnitude, in most orthodontic treatments and it affects the biomechanics of the tooth movement. However, the influence of loop design on resistance to sliding is currently unknown. Methods: In total, 12 stainless steel orthodontic wires of different sizes (0.016″×0.022″; 0.017″×0.025″), loop height (6mm, 8mm, 10mm), and loop type (open, close) were analyzed. Wires were tied with elastic ligatures to a bracket and tested during sliding at 0.5 mm/min. Straight wires were used as controls. Differences in the force to start the sliding ( N ), force during the sliding ( N ), and displacement to start the sliding (mm), were evaluated with Kruskal–Wallis one-way analysis of variance and Mann–Whitney tests (α=0.05). Results: Open loops had a lower force to start the sliding compared to straight wires ( p

In modern steam power plants, the ever-increasing complexity requires great reliability and flexibility of the control system. Hence, in this paper, the feasibility of a distributed model predictive control (DiMPC) strategy with an extended prediction self-adaptive control (EPSAC) framework is studied, in which the multiple controllers allow each sub-loop to have its own requirement flexibility. Meanwhile, the model predictive control can guarantee a good performance for the system with constraints. The performance is compared against a decentralized model predictive control (DeMPC) and a centralized model predictive control (CMPC). In order to improve the computing speed, a multiple objective model predictive control (MOMPC) is proposed. For the stability of the control system, the convergence of the DiMPC is discussed. Simulation tests are performed on the five different sub-loops of steam/water loop. The results indicate that the DiMPC may achieve similar performance as CMPC while outperforming the DeMPC method.

DC–AC input-series-output-series (ISOS) systems are very suitable for high input voltage and high output voltage power conversion applications. The implementation of the compound balanced control strategy is presented for the DC–AC ISOS system to achieve input voltage sharing (IVS) and output voltage sharing (OVS). The output filter inductor current or the output filter capacitor current adopted as the feedback signal for the inner current loops of each module, respectively, is analyzed and compared. Taking the output-filter-capacitor-current method as an example, the decoupling relationship between the control loops is analyzed and the loop design procedure is given. The simulation and experimental results are provided to verify the effectiveness of the proposed control method. Furthermore, this chapter presents a new solution dedicated to distributed configuration on the basis of centralized control, which can improve the reliability of the system.

More and more semiconductor manufacturers are adopting “smart” technology to improve throughput, yield and factory efficiency. In this paper, we examine how smart technology addresses two big challenges of wire bonding including fine pitch Cu first bond process and multi-tier looping. Fine pitch Cu first bond process has smaller process window and is harder to optimize than the traditional Au wire process. Through extensive research and development, a smart response based process was developed to provide wider process windows and easier adjustments. The main input to this process is desired ball diameter. Based on the desired ball diameter and other device information, optimal bonding parameters are calculated. This new smart 1st bond process is compared to traditional process to demonstrate fine pitch Cu wire bonding capability. In addition to the response based process with automatic parameter calculation, real time control is added for process monitoring and closed loop control. A new feature called Deformation Control is developed to control ball deformation using real time bonder signal feedback. Test results show that the ball size range and shear C pk is significantly improved using this feature.The second area where major improvements have been made using smart wire bonding technology is multi-tier looping. For multi-tier devices, multiple tiers of loops with different loop heights and wire lengths need to be optimized to ensure high yield wire bonding production. A 1000 +I /O multi-tier package often requires more than 100 looping parameter groups. This results in months of looping development before a new device can be run in production. A new smart looping process was developed to address these challenges. The new looping process contains a 3D Loop Design software (3D AutoOLP) which is an offline loop design tool, and a wire loop model (ProCu Loop) that automatically calculates the looping motions to produce desired loop shapes. Four different real life applications were designed and tested with the new looping process and compared to traditional method. The average optimization time is reduced from 6 weeks to 1 week for these packages and there is a more than 50% reduction of the number of looping parameter groups. In addition, real time loop height monitor is developed to monitor loop height during production.

The number of heating and cooling system using vertical borehole heat exchangers is increasingly rapidly in Sweden. Currently, there are over 600,000 installations, mostly using U-tube ground collectors. In recent years, several new ground collectors with innovative designs and configurations have been launched. They claim to have superior performance and competitive advantages over the conventional collectors.This project was aimed at assessing the performance and effectiveness of various types of ground collectors through full-scale experimental testing. The tested types of ground collectors included single U-tube, double U-tube configured in parallel, double U-tube configured in series, coaxial and U-tube with internally rifled pipes.The ground collectors were tested one after another in the same borehole heat exchanger over a period of two and a half years. The testing was performed in both heat-injection and heat-extraction modes with flows ranging from near-laminar to fully turbulent. A custom-built thermal response test rig was developed to perform tests of this type. To ensure similar geothermal conditions for all tests, the ground was rested long enough to allow full thermal recovery before each test.Among all tested ground collectors, the coaxial collector had the most consistent thermal and hydraulic performance over the tested range of thermal and pumping power conditions. However, the first cost and the time and labour expense for installing the coaxial collector were substantially higher than any other type of ground collectors. A project-specific cost-benefit analysis was deemed necessary to determine if the thermal and pump energy saving from the coaxial and other new collectors are large enough to overweigh their higher first costs and installation difficulties.Among other collectors, the U-tube collector with internally rifled pipes had inferior thermal and hydraulic performance than the ordinary U-tube collector. Double U-tube collector, configured in series, had by far the worst hydraulic performance among all tested ground collectors.The results from this project have been presented in six technical reports, three book chapters, and eleven journal and conference proceeding papers. Some more publications are in the pipeline and will be published in 2019.

Purpose To report a rare case of severe capsular phimosis after toric trifocal intraocular lens implantation, in a patient who was already on systemic immunosuppression and to present a modified fixation technique, based on the four-flanged prolene technique, which could be adapted for fixation of intraocular lenses of the double-C-loop design. Observations A 33 year old gentleman, who underwent uneventful, sequential, bilateral phacoemulsification with implantation of toric trifocal intraocular lenses, presented 6 weeks post-operatively, with severe capsular phimosis, causing decentration of the IOL and deformation of the haptics in both eyes. The left eye was successfully managed by Nd-YAG laser anterior capsulotomy, while the right eye required surgical intervention. Conclusion and importance In the present case report, we describe a novel technique to successfully reposition and realign a decentered toric trifocal intraocular lens of the double C-loop haptic design, after severe capsule phimosis., Highlights • A novel technique using four-flanged prolene suture to reposition a toric-trifocal IOL without the need for explantation. • Secondary IOL repositioning and fixation made possible even for toric trifocal IOLs. • Successful re-centration and re-alignment of a toric-trifocal IOL after aggressive capsular phimosis.

Purpose To study the deformation of 4 suture configurations used in flexor tendon repair using fluoroscopy. Methods All flexor tendon repair techniques have a longitudinal component, a link component, and/or a transverse component. We had previously described 4 types of link components, namely an arc (grasping loop), a simple loop (locking loop), a complex loop, and a knot. The effect of loading on suture configurations using each of these link components was tested in flexor tendon from the first ray of porcine feet. Forty flexor tendons were divided into 4 groups of 10 each, and one-half of a tendon repair was simulated on each group using 0.5 mm stainless steel wire. The tendons were mounted on a materials testing machine, and tensile force was applied until failure. The deformation of the suture within the tendon substance was observed using an image intensifier, and the maximal load to failure was measured. Results The loading of the suture led to unraveling of the suture in an arc, constriction and unraveling in a simple loop, and initial constriction with no further change of the construct in the complex loop with no change in the knot design. The mean pullout strength of the complex loop was statistically greater than all the other 3 designs. Conclusions Each of the link component designs demonstrated unique deformation characteristics. The complex loop design had the strongest grasping ability. Clinical relevance This study identified the differences in the deformation characteristics of the 4 types of link components used in flexor tendon repair. This knowledge may allow for the development of better flexor tendon repair techniques and the adoption of a more precise classification of flexor tendon repair techniques.