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AbstractThe Fukushima Daiichi accident prompted the nuclear community to find a new solution to reduce the risk in nuclear power plants (NPPs) due to beyond-design-basis external events (BDBEEs). An implementation guide for diverse and flexible coping strategies (FLEX) has been presented by the Nuclear Energy Institute to manage the challenges of BDBEEs and enhance reactor safety. Due to the uniqueness of the FLEX systems, these systems can potentially carry dependencies among components not commonly modeled in NPPs. In this study, we investigate the effectiveness and applicability of both Bayesian networks (BNs) and discrete-time Bayesian networks in the reliability analysis of FLEX equipment. The study compares BNs with two other reliability assessment methods: fault tree and Markov chain. These methods are also shown to be capable of mapping into BNs to perform a reliability analysis of FLEX systems. A neutral dependency algorithm is used to simplify the conditional probability tables and reduce the complexity of the BNs. The results indicate that BNs are not only a powerful method for modeling FLEX strategies but are also effective techniques for inclusion of the dynamics of FLEX equipment in probabilistic risk analysis.

BACKGROUND: Recent studies have shown the feasibility of performing lower extremity revascularization based on noninvasive vascular studies alone. METHODS: We undertook a prospective study of patients with lower extremity ischemia who underwent revascularization without preoperative angiography. Preoperative evaluation was done with noninvasive studies including segmental pressures, ankle arm index, duplex scan, and selective use of magnetic resonance angiography. Intraoperative angiography and intra-arterial pressure measurements were used prior to revascularization. Standard patency analysis and follow-up examination were performed. RESULTS: In all, 47 patients underwent 65 procedures (27 iliac, 38 infrainguinal) over a 3-year period. Intraoperative angiography and operative findings correlated with the noninvasive studies. There was one immediate failure, and life table analysis demonstrated primary patency rates of 92% for iliac reconstruction (29 months) and 82% for infrainguinal reconstruction (40 months). CONCLUSION: Preoperative evaluation for lower extremity revascularization utilizing only noninvasive vascular testing gives satisfactory results and is a safe and potentially durable alternative to routine preoperative angiography in most cases. Am J Surg. 1998;176:203-207. [C] 1998 by Excerpta Medica, Inc.

Sometimes in the middle of the night Michael J. Grisanti would hear voices. They were the voices of his customers pleading with him. And it was those pleas that finally [...]

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We investigated type 2 diabetes (T2D) genetic susceptibility via multi-ancestry meta-analysis of 228,499 cases and 1,178,783 controls in the Million Veteran Program (MVP), DIAMANTE, Biobank Japan and other studies. We report 568 associations, including 286 autosomal, 7 X-chromosomal and 25 identified in ancestry-specific analyses that were previously unreported. Transcriptome-wide association analysis detected 3,568 T2D associations with genetically predicted gene expression in 687 novel genes; of these, 54 are known to interact with FDA-approved drugs. A polygenic risk score (PRS) was strongly associated with increased risk of T2D-related retinopathy and modestly associated with chronic kidney disease (CKD), peripheral artery disease (PAD) and neuropathy. We investigated the genetic etiology of T2D-related vascular outcomes in the MVP and observed statistical SNP–T2D interactions at 13 variants, including coronary heart disease (CHD), CKD, PAD and neuropathy. These findings may help to identify potential therapeutic targets for T2D and genomic pathways that link T2D to vascular outcomes.

Background: Because Alzheimer’s Disease (AD) has very complicated pattern changes, it is difficult to evaluate it with a specific factor. Recently, novel machine learning methods have been applied to solve limitations. Objective: The objective of this study was to investigate the approach of classification and prediction methods using the Machine Learning (ML)-based Optimized Combination-Feature (OCF) set on Gray Matter Volume (GMV) and Quantitative Susceptibility Mapping (QSM) in the subjects of Cognitive Normal (CN) elderly, Amnestic Mild Cognitive Impairment (aMCI), and mild and moderate AD. Materials and Methods: 57 subjects were included: 19 CN, 19 aMCI, and 19 AD with GMV and QSM. Regions-of-Interest (ROIs) were defined at the well-known regions for rich iron contents and amyloid accumulation areas in the AD brain. To differentiate the three subject groups, the Support Vector Machine (SVM) with the three different kernels and with the OCF set was conducted with GMV and QSM values. To predict the aMCI stage, regression-based ML models were performed with the OCF set. The result of prediction was compared with the accuracy of clinical data. Results: In the group classification between CN and aMCI, the highest accuracy was shown using the combination of GMVs (hippocampus and entorhinal cortex) and QSMs (hippocampus and pulvinar) data using the 2nd SVM classifier (AUC = 0.94). In the group classification between aMCI and AD, the highest accuracy was shown using the combination of GMVs (amygdala, entorhinal cortex, and posterior cingulate cortex) and QSMs (hippocampus and pulvinar) data using the 2nd SVM classifier (AUC = 0.93). In the group classification between CN and AD, the highest accuracy was shown using the combination of GMVs (amygdala, entorhinal cortex, and posterior cingulate cortex) and QSMs (hippocampus and pulvinar) data using the 2nd SVM classifier (AUC = 0.99). To predict aMCI from CN, the exponential Gaussian process regression model with the OCF set using GMV and QSM data was shown the most similar result (RMSE = 0.371) to clinical data (RMSE = 0.319). Conclusion: The proposed OCF based ML approach with GMV and QSM was shown the effective performance of the subject group classification and prediction for aMCI stage. Therefore, it can be used as personalized analysis or diagnostic aid program for diagnosis.

An interview with Jon L. Beatty, chief executive officer CEO at the Flight Safety Foundation is presented. He discusses the shortage of pilots that is a biggest concern for the foundation and mentions that the aviation is the safest form of transportation. He mentions that Flight Safety is an independent international organization working for the improvement of global aviation safety. He comments on the integration of unmanned aircraft.

An interview with National Aeronautics and Space Agency (NASA) Aeronautics Research Mission Directorate administrator Jaiwon Shin is presented. He talks about new technologies in air travel. Shin explains the possibilities for new segments in tube-and-wing aircraft at lower altitude such as small unmanned aerial systems (UAS). He discusses the hybrid wing body configuration for lower noise and fuel consumption. He adds about sharing NASA research with all U.S. aviation industry companies.

Objective One of the major obstacles in applying decellularized organs for clinical use is the recellularization step, during which huge numbers of cells are required to develop whole livers. We established a simple protocol for constructing a bioartificial hepatic lobe and investigated its biocompatibility.Methods The right lateral lobe of porcine liver was decellularized using 0.1% sodium dodecyl sulfate through the right branch of the portal vein. Decellularized lobes were evaluated by histological and biochemical analyses. DNA content was quantified to validate the decellularization protocol. The presence of immunogenic and pathogenic antigens was checked to exclude potential rejection and thrombosis after xenotransplantation. Xeno-reactivity of decellularized tissue against human peripheral blood mononuclear cells was examined. Cytotoxicity was evaluated against hepatocarcinoma cells. Finally, scaffolds were incubated in collagenase for biodegradation testing.Results The decellularized lobe preserved the three-dimensional architecture, ultrastructure, extracellular matrix components, and vasculature. Scaffolds were almost depleted of DNA in addition to antigenic and pathogenic antigens, which are considered barriers to xenotransplantation. The human immune response against scaffolds was considered non-significant. Our matrices were biocompatible and biodegradable.Conclusions We successfully developed a non-cytotoxic, non-immunogenic, and biodegradable porcine hepatic lobe for future liver regeneration and bioengineering.

Purpose The aims of this study were to investigate the effects of sterilization with peracetic acid (PAA) and ethanol on the biological activity of porcine liver scaffolds and to develop a new technique for sterilization using slightly acidic electrolyzed water (SAEW).Methods Decellularization of liver slices was performed using 0.1% sodium-dodecyl-sulfate, then evaluated by histological and polymerase chain reaction analyses. Decellularized slices were treated with either PAA or ethanol or SAEW, and then DNA content was quantified. We determined sterilization efficiency by culturing scaffolds in culture medium and on blood agar. We next analyzed the glycosaminoglycan and collagen contents of the scaffolds. Finally, we tested the cytotoxicity of the scaffolds as well as the effects of sterilization on host cell attachment and proliferation.Results Complete cell and antigenic epitopes removal emphasized the decellularization efficiency. PAA and SAEW treatments achieved the highest efficiency of sterilization compared to that of the ethanol treated scaffolds, and were able to remove a considerable fraction of DNA from decellular-ized livers. The retained glycosaminoglycan content decreased in all treatments in the following order: SAEW, ethanol, and PAA. Ethanol caused a significant loss in collagen content compared to the other groups. A cytotoxicity evaluation revealed that all scaffolds were nontoxic. SAEW-treated scaffolds supported cell attachment and proliferation at a significantly higher rate than other groups.Conclusions These data suggest that SAEW is highly efficient for sterilizing scaffolds and allowed the scaffolds to retain their bioactivity in addition to its high efficiency for cell remnant removal.

A multifunctional and high-efficiency microfluidic device for droplet generation and fusion is presented. Through unique design of the micro-channels, the device is able to alternately generate droplets, generating droplet ratios ranging from 1 5 to 5 1, and fuse droplets, enabling precise chemical reactions in several picoliters on a single chip. The controlled fusion is managed by passive control based on the channel geometry and liquid phase flow. The synthesis of CdS nanoparticles utilizing each fused droplet as a microreactor for rapid and efficient mixing of reagents is demonstrated in this paper. Following alternating droplet generation, the channel geometry allows the exclusive fusion of alternate droplets with concomitant rapid mixing and produces supersaturated solution of Cd2and S2−ions to form CdS nanoparticles in each fused droplet. The spectroscopic properties of the CdS nanoparticles produced by this method are compared with CdS prepared by bulk mixing.

The article assesses the future of air travel following the crash of the Germanwings Airbus A320 in 2015. Topics discussed include ground-based takeover of commercial flight such as that of a BAE Systems tested in 2013 and the patented "uninterruptible autopilot" system from Boeing, the debate over cockpit automation citing differences in philosophies between Boeing and Airbus and questions about remote piloting.

Information about the Sci-Tech 2016 panel discussion held in San Diego, California on aerospace innovation is presented. Topics include money raised through the online fundraising site Kickstarter for the launch of KickSat satellite into low-Earth orbit, use of social media inspiring aerospace innovation, and the development of the tilt rotor technology. The panel featured Hans Mark, former secretary at the U.S. Air Force.

The article reports if the U.S. Air Force's prize for turbo-shaft jet engine as of October 2015 will be enough to entice competitors to build demonstration hardware for the prize's verification phase. Topics include the need for winning entries to a pass a verification test, and the launch of the competition in May 2015 by the U.S. Air Force Research Laboratory.

The article reports on the U.S. Navy's Aegis ships and their interceptors. She mentions its capability in intercepting cruise and ballistic missiles such as the Standard Missile-6 Dual 1 from Raytheon Co. An overview of the perspective of the company's terminal program director Tirso Rosario on its potential is also presented.

The article discusses a summit on connected aircraft held in Chantilly, Virginia in June 2015. Topics addressed include aviation and the Internet of Things (IoT), aircraft avionics and the proliferation of travel applications like the Uber and Airbnb. The summit featured speakers such as Howard Charney and Andrew Kemmetmueller.