Sleeve Device Research Articles

EE13 Cost-Effectiveness Analysis of Duodenal–Jejunal Bypass Sleeve Device for People With Obesity

EE13 Cost-Effectiveness Analysis of Duodenal–Jejunal Bypass Sleeve Device for People With Obesity

Enhancing Structural Resilience: Exploring the Novel Sleeve Method for Steel T-Stub Connections

A new sleeve device has been introduced with the aim of enhancing the performance of steel structures under extreme loading conditions. Previous research has primarily focused on numerical simulations of this sleeve's application, emphasizing the need for further investigation to validate its effectiveness. This research paper presents a numerical analysis that explores how the sleeve device influences the deformation capacity and strength of a bolt up to the point of failure. The study involved the use of a T-stub connection with multiple sleeves, each featuring different geometric parameters. To assess the impact on strength and deformation capacity, a comparison was drawn between these findings and the behavior of a T-stub bolted connection without using the sleeve. In addition, Finite Element (FE) models were employed for additional parametric studies. The test outcomes demonstrated a substantial increase in the deformability of the bolted connection when utilizing the sleeve device, all the while preserving the strength and initial stiffness of the bolts. This proposed sleeve method in the study significantly enhances the connection's capacity by delaying bolt failure.

A Novel Method to Improve Robustness of End Plate Connections at Elevated Temperatures Using Bolt Sleeves

The robustness of steel frames during fire events is primarily controlled by the rotational capacity of beam to column connections. Higher values of rotational capacity allow the beam to develop catenary action which enhances the survivability of the steel frame. The present study proposes a novel device to increase rotational capacity of steel end plate beam-column connections at elevated temperatures. By inserting a steel sleeve with a designated length, thickness and wall curvature between the end plate and the washer, the load path between the end plate and the bolts can be interrupted, promoting a more ductile response. An analytical solution predicting the sleeve design parameters is also presented. It is concluded that the proposed device can significantly increase the rotational capacity of the end plate connection at elevated temperatures. Furthermore, a detailed numerical investigation on end plate connections with various failure modes concluded that the proposed sleeve device does not have any negative effect on the connection performance at elevated temperatures.

Human Arm Workout Classification by Arm Sleeve Device Based on Machine Learning Algorithms.

Wearables have been applied in the field of fitness in recent years to monitor human muscles by recording electromyographic (EMG) signals. Understanding muscle activation during exercise routines allows strength athletes to achieve the best results. Hydrogels, which are widely used as wet electrodes in the fitness field, are not an option for wearable devices due to their characteristics of being disposable and skin-adhesion. Therefore, a lot of research has been conducted on the development of dry electrodes that can replace hydrogels. In this study, to make it wearable, neoprene was impregnated with high-purity SWCNTs to develop a dry electrode with less noise than hydrogel. Due to the impact of COVID-19, the demand for workouts to improve muscle strength, such as home gyms and personal trainers (PT), has increased. Although there are many studies related to aerobic exercise, there is a lack of wearable devices that can assist in improving muscle strength. This pilot study proposed the development of a wearable device in the form of an arm sleeve that can monitor muscle activity by recording EMG signals of the arm using nine textile-based sensors. In addition, some machine learning models were used to classify three arm target movements such as wrist curl, biceps curl, and dumbbell kickback from the EMG signals recorded by fiber-based sensors. The results obtained show that the EMG signal recorded by the proposed electrode contains less noise compared to that collected by the wet electrode. This was also evidenced by the high accuracy of the classification model used to classify the three arms workouts. This work classification device is an essential step towards wearable devices that can replace next-generation PT.

Enhancing progressive collapse resistance of steel structures using a new bolt sleeve device

In the present study, frame robustness is enhanced by improving the contribution of the bolts to the rotational capacity of connections; the higher the bolts' elongation, the higher the rotational capacity that can be achieved. The proposed method comprises a hollow steel sleeve, with a predetermined wall curvature, that is inserted between the washer and the end plate interrupting the load path in the connection thus enabling a more ductile response. In order to demonstrate the efficacy of the proposed method, end plate connections with varying sleeve parameters are numerically examined using verified FE models. The proposed system significantly increases the ductility and strength of the connection by up to 2.6 and 2.5 times that of the standard connection, respectively. Additionally, different ductile responses can be achieved based on the sleeve parameters without changing the configuration of the connection.

Haunch connecting techniques in a self-centering modular steel structure connection system

High extent of mechanized assembly is one of the development concepts of the modular construction, allowing the full development of its superiority in construction efficiency and quality. The primary focus of this research is to propose novel types of connecting techniques between the haunch brace and the module in the self-centering modular steel structure (SC-MSS) connection system, which horizontally inserts the long through-bolts inside the columns or fixes the sleeve device by bolts around the periphery of the columns to achieve stable and effective connecting performance and well installation convenience at the construction site. The functional mechanism of the traditional and novel haunch connecting techniques are clarified and the seismic performance of the SC-MSS connections with different connecting techniques are investigated due to monotonic and cyclic loadings. Results demonstrate that the strength and stiffness of all connections develop as the similar trend and stable hysteretic responses with satisfactory self-centering capability can be observed. Furthermore, the haunch reaction force is reasonably distributed and effectively transmitted under the proposed connecting techniques, which could control the stress level in the haunch intersection regions of the modules and well protect the key structural members. The mechanical and deformation mechanisms of the haunch connecting techniques are analyzed and some design considerations are provided accordingly for offering the guidance for the engineering design and application of SC-MSS connection systems.

Design considerations for photovoltaic energy harvesting in wearable devices

Wearable technology is emerging as a solution for various bio-mechanic and health-metric applications. Solar photovoltaic energy is a viable supplemental power source that can reduce battery size requirements in wearables. This study outlines the considerations for a wearable sleeve device and its associated power converter system using commercially-available flexible photovoltaic panels located on the forearm. Investigation of the effects of curvature shows that while curvature of the panel around a forearm does reduce output power, the angle relative to the light source has a more pronounced effect on both output power and voltage characteristics. Among various panel arrangements on the forearm, that with five individual panels of smaller width provided the highest output power after the boost converter power stage. Testing under various static positions, the PV sleeve provided up to 94 mW outdoors, which can effectively reduce the battery size while maintaining user safety.

New Technique to Improve the Ductility of Steel Beam to Column Bolted Connections: A Numerical Investigation

A novel method to improve the robustness of steel end plate connections is presented in this paper. Existing commonly adopted techniques alter the stiffness of the beam or the end plate to improve the connection’s robustness. In this study, the robustness is enhanced by improving the contribution of the bolts to the rotational capacity of connections; the higher the bolts’ elongation, the higher the rotational capacity that can be achieved. However, the brittleness of the bolt material, combined with its small length, results in negligible elongation. Alternatively, the load path between the end plate and the bolts can be interrupted with a ductile element to achieve the required elongation. This can be achieved by inserting a steel sleeve with a designated length, thickness, and wall curvature between the end plate and the washer. The proposed sleeve should be designed so that its ultimate capacity is less than the force in the bolt at failure; accordingly, the sleeve develops a severe bending deformation before the failure of any connection components. Using a validated finite element model, end plate connections with various parameters are numerically investigated to understand the performance of the sleeve device. The proposed system substantially enhances the rotational capacity of the connections, ranging between 1.37 and 2.46 times that of the standard connection. It is also concluded that the sleeved connections exhibit a consistent elastic response with the standard connections, indicating the proposed system is compatible with codified elastic design approaches without modification. Furthermore, for a specific connection, various ductile responses can be achieved without altering the connection capacity nor configuration.

Quantifying Erosion of Downhole Solids Control Equipment during Openhole, Multistage Fracturing

SummaryProppant flowback from hydraulic fracturing is widespread and costly due to erosion and/or blockage of producing hydrocarbons as proppant may accumulate downhole. Several strategies have been applied to avoid or minimize proppant flowback, such as treatment optimization to maximize pack stability, resin-coated proppant, limiting drawdown, or letting it flow to deal with the consequences later. Another strategy to avoid proppant flowback is to install sand control equipment integrated into a sliding sleeve device (SSD) as part of the completion string. Although the presence of sand control equipment can mitigate the problem, it raises concern about erosion during fracturing. Although some installations have been successful, one is known to have experienced sand control failure. This study aimed to understand the effect of hydraulic fracturing on the erosion of completion equipment with an objective of improving the design to, as much as possible, prevent erosion failure. Computational fluid dynamics (CFD) was used to evaluate the root cause and identify more robust design solutions.The first step was to identify the most probable causes of sand control failure during multistage fracturing (MSF) in openhole (OH) horizontals. The as-is completion was then modeled, along with the screen, SSD, fracturing port, and OH isolation packer. Because the fracture location between two packers is unknown, and the fracturing port was located between multiple screen/SSD assemblies, annular flow across the assembly in both directions was considered. State-of-the-art CFD simulations were then performed on the installed design using actual flow conditions (rates, slurry properties, treatment time) from the failed installation. A new quasidynamic mesh (QDM) methodology was developed, which yielded more realistic (albeit still conservative) erosion-depth predictions. The results revealed areas for improving the design of key components of the 10-ksi-rated system, and CFD was rerun to confirm erosion resistance targets. Design modifications were implemented, and improved products were then manufactured and field tested. For a new 15-ksi design, particle–particle interaction was added to the CFD analysis. The results of the CFD analysis and field test are presented herein.

Physiotherapy: Design and Implementation of a Wearable Sleeve using IMU Sensor and VR to Measure Elbow Range of Motion

Range of motion (RoM) is the measurement of angular movement of joints that defines the joints flexibility. It is crucial to measure RoM while performing musculo-skeletal diagnostics. The physiotherapy and the visits to hospitals can be very costly and demands a great deal of time; also most of the current digital instruments, used to measure RoM, are very expensive and hard to use. In this paper a digital wearable sleeve device is designed and tested which is cheap, time efficient and easy to use. The designed device is tested to be within 95 % agreement with Universal Goniometer (UG) when tested using Bland Altman Plots. Patients can take their measurements on their own and visualize results on their desktops or mobile phones. Patients also have graphical feedback, highlighting the extent of variation between their exercise performance and standard exercise. In addition to this; patients can also compare their current exercise from previous exercise using Kalmogorov-Simronov (K-S) test automatically. To make exercising more fun, we have developed 3D VR (Virtual Reality) gaming environment for elbow flexion, elbow supination and pronation and elbow extension exercises where patient can exercise in an interactive environment and visualize their progress side by side.

СПЕЦИАЛЬНЫЙ МЕТЧИК ДЛЯ НАРЕЗАНИЯ ВНУТРЕННИХ МЕЛКОРАЗМЕРНЫХ РЕЗЬБ

The paper presents the original design of a special tap for cutting precise threads. Distinctive design features of the tap are: the presence of the rear threaded guide that together with the copier threaded sleeve device perceives the axial forces and provides the tap axial feed strictly corresponding to the step of the thread being cut, excluding its breaking under the action of axial forces; the presence of a smooth front guide part with the direction on the cut hole, to reduce the influence of radial forces leading to the breakdown of the thread due to radial vibrations of the tap; the presence of the chamfer that implements the most technological cutting scheme such as flank infeed. A prototype of a special tap made on a turning and milling machine tool is presented, confirming the manufacturability of the proposed tool design. Research conducted in the field of engineering analysis with the CAE system Ansys shows a significant increase in structural rigidity and in natural frequencies.

Transition‐Metal Oxides Anchored on Nitrogen‐Enriched Carbon Ribbons for High‐Performance Pseudocapacitors

Increasing demand for effective energy-storage systems derived from low-cost and ecofriendly raw materials has aroused wide concern. In this contribution, we propose nitrogen-abundant amorphous micron-sized carbon ribbons (AMCRs) originating from biomass raupo as a novel substrate due to their specific quasi 2D morphologies and outstanding dispersion ability. Owing to the innate nitrogen atoms on the surface of AMCRs, ultrathin binary and ternary metal oxide (NiO, CoO, and NiCo2 O4 ) nanosheets can be uniformly developed under benign conditions. These three composites were separately fabricated as electrodes for supercapacitors in a three-electrode system and exhibited favorable activities. Among them, the ternary metal oxide composites NiCo2 O4 @AMCRs delivered the supreme specific capacitance of 1691 F g-1 and best cycling stability (89 % capacity retention over 10,000 cycles). Moreover, symmetric supercapacitors (NiCo2 O4 @AMCRs//NiCo2 O4 @AMCRs) were assembled inside sleeve devices with 2 m KOH aqueous electrolyte, which demonstrated admirable cyclic stability (79.1 % capacity retention over 8,000 cycles), and an excellent energy density of 26 Wh kg-1 at the power density of 1.8 kW kg-1 .

A randomised controlled trial of a duodenal-jejunal bypass sleeve device (EndoBarrier) compared with standard medical therapy for the management of obese subjects with type 2 diabetes mellitus

IntroductionThe prevalence of obesity and obesity-related diseases, including type 2 diabetes mellitus (T2DM), is increasing. Exclusion of the foregut, as occurs in Roux-en-Y gastric bypass, has a key role in...

Axillary reverse lymphatic mapping reduces patient perceived incidence of lymphedema after axillary dissection in breast cancer

BackgroundLymphedema is a feared complication of many patients following axillary lymph node dissection for breast cancer. Axillary reverse lymphatic mapping (ARM) was adopted to decrease the incidence of lymphedema. MethodsA retrospective review was conducted on 139 patients with breast cancer who had greater than 10 lymph nodes removed. A survey was sent to patients to identify those with lymphedema. ResultsOne hundred nine women were contacted via mail survey to determine the presence of lymphedema. Of the 46 surveys returned, the incidence of lymphedema was 39%. Twenty-seven percent of the ARM group identified themselves as having lymphedema compared with 50% in non-ARM group. Eighteen percent of women in the ARM group needed an arm sleeve for treatment compared with 45.8% in the non-ARM group. ConclusionsThe incidence of perceived lymphedema and the need for arm compression sleeve devices were lower in the ARM cohort. ARM should be adopted to decrease patient perception of lymphedema.

Seismic performances of RC columns reinforced with screw ribbed reinforcements connected by mechanical splice

Various types of reinforcement splicing methods have been developed and implemented in reinforced concrete construction projects for achieving the continuity of reinforcements. Due to the complicated reinforcement arrangements and the difficulties in securing bar spacing, the traditional lap splicing method, which has been widely used in reinforced concrete constructions, often shows low constructability and difficulties in quality control. Also, lap spliced regions are likely to be over-reinforced, which may not be desirable in seismic design. On the other hand, mechanical splicing methods can offer simple and clear arrangements of reinforcement. In order to utilize the couplers for the ribbed-deformed bars, however, additional screw processing at the ends of reinforcing bars is typically required, which often lead to performance degradations of reinforced concrete members due to the lack of workmanship in screw processing or in adjusting the length of reinforcing bars. On the contrary, the use of screw-ribbed reinforcements can easily solve these issues on the mechanical splicing methods, because it does not require the screw process on the bar. In this study, the mechanical coupler suitable for the screw-ribbed reinforcements has been developed, in which any gap between the reinforcements and sleeve device can be removed by grouting high-flow inorganic mortar. This study presents the uniaxial tension tests on the screw-ribbed reinforcement with the mechanical sleeve devices and the cyclic loading tests on RC columns with the developed coupler. The test results show that the mechanical sleeve connection developed in this study has an excellent splicing performance, and that it is applicable to reinforced concrete columns with a proper confinement by hoop reinforcement.

Isolated duodenal exclusion increases energy expenditure and improves glucose homeostasis in diet-induced obese rats

Roux-en-Y gastric bypass (RYGB) in rodent models reduces food intake (FI), increases resting energy expenditure (EE), and improves glycemic control. We have shown that mimicking the duodenal component of RYGB by implantation of a 10-cm endoluminal sleeve device (ELS-10) induces weight loss and improves glycemic control in diet-induced obese (DIO) rats. We sought to determine the mechanisms and structural requirements of these effects. We examined the effects of ELS-10 devices implanted in male DIO rats on body weight, food intake (FI), meal patterns, total and resting EE, and multiple parameters of glucose homeostasis, comparing them with sham-operated (SO) rats and with SO rats weight matched to the ELS-10-treated group. To determine the extent of duodenal exclusion required to influence metabolic outcomes, we compared the effects of implanting 10-, 4-, or 1-cm ELS devices. ELS-10 rats exhibited 13% higher total and 9% higher resting EE than SO controls. ELS-10 rats also exhibited enhanced postprandial GLP-1 secretion and improved glucose tolerance and insulin sensitivity out of proportion to the effects of weight loss alone. Implantation of 4- or 1-cm ELS devices had no effect on EE and limited effects on glucose homeostasis. Complete duodenal exclusion with ELS-10 induces weight loss by decreasing FI and increasing EE and improves glycemic control through weight loss-independent mechanisms. Thus signals originating in the proximal small intestine appear to exert a direct influence on the physiological regulation of EE and glucose homeostasis. Their selective manipulation could provide effective new therapies for obesity and diabetes that mimic the benefits of RYGB.

Evaluation of Commercially Available Port Access Devices for Single-incision Laparoscopy

Laparoendoscopic single-site surgery has created a need for new technologies to simplify and expedite these procedures. We evaluated 3 different commercially available single-incision laparoscopic port access devices for their ease of use. Four laparoscopic surgeons performed multiple laparoscopic procedures through a single fascial incision in a porcine model. Three different commercially available access devices were used and evaluated for performance on a 5-point Likert scale. All procedures were successfully completed. Tissue dissection and retraction were challenging because of instrument crowding and lack of triangulation. Two of the tested devices included trocars in the design, maximum trocar size of 12 mm versus 15 mm. Quoted cost for the devices varied widely with the sleeve device at the lower end and the disk shaped at the higher end. All tested devices allowed the performance of the attempted procedures. Challenges continue to exist and continued improvement in design is necessary.

Fifty years of Australian gastroenterology and hepatology: A golden era of contributions to the region

Fifty years of Australian gastroenterology and hepatology: A golden era of contributions to the region

A biomechanical study on preloaded compression effect on headless screws

Commonly used headless design screws such as Acutrak and Herbert screws have limited compressive effect on short fragment fixation. Therefore, we investigated whether preloaded compression techniques could be helpful in improving the compression effect. A prototype of interfragmentary compression screw was designed with a constant pitch to avoid self-compressive effect. Preloaded compression was achieved with a sleeve device before the insertion of the trailer side (the leading side was inserted). Prototype screw test results were compared with those of Acutrak and Herbert screws. Eight pullout and eight compression tests were performed for each of the three screws using homogenous synthetic bone blocks. The mean pullout forces of the Acutrak, Herbert and prototype screws were 67.21, 45.90 and 61.88 N, respectively. Preloaded compression (18.15 N) was higher than the compression produced by Acutrak (15.27 N) and Herbert (15.11 N) screws (p < 0.05). However, at the end of full insertion, half of the power obtained by preloaded compression was lost. Preloaded compression technique was successful in attaining maximum compression rate. During trailing-side insertion, constant pitch design failed to keep compression rate. Variable pitches can be useful to preserve or increase compression rate. In addition, sleeve usage may be more advantageous in thin fragment fixation.

Manometric evidence for a phonation-induced UES contractile reflex

The mechanism against entry of gastric content into the pharynx during high-intensity vocalization such as seen among professional singers is not known. We hypothesized that phonation-induced upper esophageal sphincter (UES) contraction enhances the pressure barrier against entry of gastroesophageal contents into pharynx. To determine and compare the effect of phonation on luminal pressures of the esophagus and its sphincters, we studied 17 healthy volunteers (7 male, 10 female) by concurrent high-resolution manometry and voice analysis. We tested high- and low-pitch vowel sounds. Findings were verified in six subjects by UES manometry using a water-perfused sleeve device. Eight of the volunteers (2 male, 6 female) had concurrent video fluoroscopy with high-resolution manometry and voice recording. Fluoroscopic images were analyzed for laryngeal movement. To define the sex-based effect, subgroup analysis was performed. All tested phonation frequencies and intensities induced a significant increase in UES pressure (UESP) compared with prephonation pressure. The magnitude of the UESP increase was significantly higher than that of the distal esophagus, the lower esophageal sphincter (LES), and the stomach. Concurrent videofluoroscopy did not show posterior laryngeal movement during phonation, eliminating a purely mechanical cause for phonation-induced UESP increase. Subgroup analysis demonstrated phonation-induced UESP increases in males that were significantly greater than those of females. Phonation induces a significant increase in UESP, suggesting the existence of a phonation-induced UES contractile reflex. UESP increase due to this reflex is significantly higher than that of the distal esophagus, LES, and stomach. The phonation-induced UESP increase is influenced by sex.