Introduction
One-anastomosis-mini-gastric bypass (OAGB-MGB) is the second most popular gastric bypass procedure with remarkable weight loss results and comorbidity resolution rates. However, some ...concerns remain regarding its postoperative complications, including protein-calorie malnutrition (PCM). We hereby report our experience with patients who returned with severe PCM after OAGB-MGB.
Methods
Patients with severe obesity presenting to our referral bariatric center underwent OAGB-MGB surgery using a 200-cm biliopancreatic limb (BPL) by a single surgical team at three university hospitals from March 2014 to February 2016.
Results
From 189 patients undergoing OAGB-MGB, seven patients (3.7%), all female, with a mean age of 46.4 ± 8.2 years and initial body mass index (BMI) of 44.2 ± 4.7 kg/m
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, were readmitted for signs of PCM. Lower extremity edema, fatigue, excessive weight loss, hypoalbuminemia, anemia, and pancytopenia were the presenting symptoms and lab findings. Revisional surgery was performed at a mean 19 ± 9.7 months after OAGB-MGB after failure of supportive measures. The mean BMI at the time of revision was 22.5 ± 2.6 kg/m
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with an excess weight loss of 109.2 ± 22.1%. After revisional surgery, one patient developed profound liver failure and expired. Another patient developed severe steatohepatitis but ultimately recovered. In the remaining five, edema and fatigue completely resolved at 1 month and hypoalbuminemia and anemia normalized at 2 months.
Conclusion
A one-fits-all BPL length of 200 cm is increasingly being questioned as it may result in an inadequate absorptive area and PCM in a subset of patients with shorter total bowel lengths, potentially placing them in danger and depriving them of bariatric surgery benefits.
The proposed indoor thermal environmental design system comprises five steps: BIM model creation, mesh generation, setting of boundary conditions, CFD simulation, and AR visualization.
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•An indoor thermal environment design system for renovation projects is developed.•Visualization of indoor CFD results in an AR environment is realized and tested.•Users can study both architectural design and thermal environment simultaneously.•Feasibility and practicality were validated through case studies of indoor greenery alternatives.
The renovation projects of buildings and living spaces, which aim to improve the thermal environment, are gaining importance because of energy saving effects and occupants' health considerations. However, the indoor thermal design is not usually performed in a very efficient manner by stakeholders, due to the limitations of a sequential waterfall design process model, and due to the difficulty in comprehending the CFD simulation results for stakeholders. On the other hand, indoor greenery has been introduced to buildings as a method for adjusting the thermal condition. Creating a VR environment, which can realistically and intuitively visualize a thermal simulation model is very time consuming and the resulting VR environment created by 3D computer graphics objects is disconnected from the reality and does not allow design stakeholders to experience the feelings of the real world. Therefore, the objective of this research is to develop a new AR-based methodology for intuitively visualizing indoor thermal environment for building renovation projects. In our proposed system, easy-to-comprehend visualization of CFD results augment the real scenes to provide users with information about thermal effects of their renovation design alternatives interactively. Case studies to assess the effect of indoor greenery alternatives on the thermal environment are performed. In conclusion, integrating CFD and AR provides users with a more natural feeling of the future thermal environment. The proposed method was evaluated feasible and effective.
Despite the potentially significant benefits that Building Information Modeling (BIM) can offer during a facility's operation and maintenance (O&M) phase, the construction industry has thus far ...mainly implemented BIM in the design and construction phases. This is because even though as-built BIM models are delivered at the handover stage, owners and operators rarely have the expertise to efficiently use and update them. Additionally, industry standards do not provide precise guidelines on aspects such as the ease of use, interoperability, and maintainability of FM-BIM, that could ensure their efficient and effective utilization. Moreover, given that these models are mainly developed for the design and construction phases, they usually contain design and construction details that are not useful for the building's operation and maintenance or lack information required for this phase. Thus, this paper investigates correspondences between as-built models and O&M requirements, using procedures and semi-automated tools to facilitate quality management activities for FM-BIM. To achieve this, a detailed checklist of items that are required in the BIM models at the handover stage and of the items that can be purged was created. This checklist is part of an overall quality framework that includes quality assurance and quality control tasks to deliver useable models for the operation and maintenance phase. Additionally, a procedure and a set of tools were investigated to semi-automatically apply a collection of the items of the checklist on as-built models. A process flow is presented to assist in quality management activities during the development of the models and to prepare them for handover. Finally, two case studies were conducted to verify and validate the applicability of the developed tools and proposed procedures.
•The research investigates a framework for quality management of BIM models to help ensure the usefulness of as-built BIM models for operation and maintenance applications.•A comprehensive checklist of information that must be present in the BIM models was created.•A procedure was investigated to semi-automatically apply a collection of the items of the checklist on BIM models.•A process flow was presented to assist in quality management activities during the development of the models.•Two case studies were implemented to validate the applicability of the developed tools and the proposed procedures.
Accurate conversion of wideband multi-GHz analog signals into the digital domain has long been a target of analog-to-digital converter (ADC) developers, driven by applications in radar systems, ...software radio, medical imaging, and communication systems. Aperture jitter has been a major bottleneck on the way towards higher speeds and better accuracy. Photonic ADCs, which perform sampling using ultra-stable optical pulse trains generated by mode-locked lasers, have been investigated for many years as a promising approach to overcome the jitter problem and bring ADC performance to new levels. This work demonstrates that the photonic approach can deliver on its promise by digitizing a 41 GHz signal with 7.0 effective bits using a photonic ADC built from discrete components. This accuracy corresponds to a timing jitter of 15 fs - a 4-5 times improvement over the performance of the best electronic ADCs which exist today. On the way towards an integrated photonic ADC, a silicon photonic chip with core photonic components was fabricated and used to digitize a 10 GHz signal with 3.5 effective bits. In these experiments, two wavelength channels were implemented, providing the overall sampling rate of 2.1 GSa/s. To show that photonic ADCs with larger channel counts are possible, a dual 20-channel silicon filter bank has been demonstrated.
Point cloud-based deep neural networks (PC-DNNs) has seen growing interest in the construction domain due to their remarkable ability to enhance Building Information Modeling (BIM)-related tasks. ...Among these tasks, Industry Foundation Classes (IFC) object classification using PC-DNNs has become an active research topic. This focus aims to mitigate classification discrepancies that occur during the interoperability of BIM tools for information exchange. However, existing studies have not fully investigated the potential of the PC-DNN models for IFC object classification. This limitation is due to the reliance on a limited number of PC-DNN models trained on small, private datasets that are not openly accessible. To address this knowledge gap, this study evaluates diverse state-of-the-art PC-DNN models for IFC object classification. Our study provides a comprehensive analysis of how different PC-DNN components and loss functions affect IFC classification, utilizing two public IFC datasets: IFCNet and BIMGEOM. Experimental results offer a detailed comparison across metrics such as accuracy, learning progression, computation time, and model parameters.
Traditional methods of supervision in the construction industry are time-consuming and costly, requiring significant investments in skilled labor. However, with advancements in artificial ...intelligence, computer vision, and deep learning, these methods can now be automated, resulting in time and cost savings, as well as improvements in product quality. This research focuses on the application of computer vision approaches to monitor the quality of welding in prefabricated steel elements. A high-performance network was designed, consisting of a video capturing station, a customized classifier based on a YOLOv4 detector and an IoU tracker, and a user interface software for any interaction with quality control workers. The network demonstrated over 98% accuracy in identifying steel connection types and detecting missed welds on the assembly line in real-time. Extensive validation was conducted using a large dataset from a real production environment. The proposed framework aims to reduce rework, minimize hazards, and enhance product quality. This research contributes to the automation of quality control processes in the construction industry.
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•We propose a method for polygonizing from a point cloud based on similarity.•Our method uses shape matching to find similar components in point cloud.•Template models are arranged ...into the similar regions found by shape matching.•The template models are either in point cloud or created by photogrammetry or CAD.
Tall vegetation in the form of green belt along the shorelines is considered an environmentally friendly and cost-effective strategy against large coastal wave damages. Comprehensive experiments were ...carried out to determine the effects of green belt on attenuation of solitary wave height and force. A novel technique based on momentum approach was used to measure direct wave force absorbed by simulated green belt. Using artificial trees with different densities, the simulated coastal forest was exposed to the breaking waves with different heights. The green belt was simulated on a movable section of a flume. The movable section with 1-m length was mounted on frictionless supports at the middle of the flume to allow direct transfer of the absorbed horizontal wave force to the load cell between moveable and stationary sections of the flume. Instantaneous wave height was measured using recorded video and pressure transducers in five points before and after the vegetation section. Results indicated a considerable effect of green belt on the reduction of the wave force and inundation depth. For example, inundation depth decreases 14%, 18%, and 29% in average for the coastal vegetation density of 30%, 50%, and 100%, respectively.
•Physical modeling of solitary wave, inundation depth and momentum absorbed by coastal flexible tree canopy using artificial tree models.•Modeling is based on the independent and measurable variables of wave, coast, and vegetation. Thus, the results can be scaled in practice.•Use of a novel technique in a laboratory flume to measure direct wave momentum absorbed by coastal vegetation canopy.
Despite their vast potential for delivering rich and intuitive visualizations of live building monitoring data, digital twins have been rarely studied in the context of thermal comfort. To narrow ...this gap, this study investigates the synergistic benefits of Building Information Modeling (BIM), the Internet of Things (IoT) and Virtual Reality (VR) for developing an immersive VR application for real-time monitoring of thermal comfort conditions. A system architecture was proposed for live calculation of the PMV/PPD indices based on ASHRAE standard 55 and enrichment of BIM-based representations of building spaces in VR environments with live IoT-enabled monitoring data. Openly available software tools were used to make the geometric and sensory data accessible within a VR application and calculate the PMV/PPD indices. Using a semi-automated method, raw thermal images streaming from a cost-effective non-intrusive sensor were processed on an affordable edge computing device to enable near real-time calculation of Mean Radiant Temperature (MRT). A prototype of the system was implemented and used in a series of experiments where a dynamic thermal environment was created in a mechanically conditioned space. The results support the consistency between the system's output and the actual thermal sensations observed under various conditions.
•BIM-IoT integrated data was used in a VR tool for live assessment of thermal comfort.•A cost-effective IoT prototype was developed to measure indoor surface temperatures.•Live MRT calculation was realized by processing raw thermal images on an edge device.•3D immersive visualizations of BIM/IoT data and live PMV/PPD charts were delivered.•The VR tool allows navigation through virtual spaces and performing what-if analyses.
Results of a self-consistent ultrafast study of nonlinear optical properties of silicon nanowaveguides using heterodyne pump-probe technique are reported. The two-photon absorption coefficient and ...free-carrier absorption effective cross-section were determined to be 0.68cm/GW, and 1.9x10(-17) cm2, respectively and the Kerr coefficient and free-carrier-induced refractive index change 0.32x10(-13) cm2/W, and -5.5x10(-21) cm3, respectively. The effects of the proton bombardment on the linear loss and the carrier lifetime of the devices were also studied. Carrier lifetime reduction from 330ps to 33ps with a linear loss of only 14.8dB/cm was achieved using a proton bombardment level of 10(15)/cm2.
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