Graphitic-BN Based Metal-free Molecular Magnets From A First Principle Study

We perform a first principle calculation on the electronic properties of carbon doped graphitic boron nitride graphitic BN. It was found that carbon substitution for either boron or nitrogen atom in graphitic BN can induce spontaneous magnetization. Calculations based on density functional theory with the local spin density approximation on the electronic band structure revealed a spin polarized, dispersionless band near the Fermi energy. Spin density contours showed that the magnetization density originates from the carbon atom. The magnetization can be attributed to the carbon 2p electron. Charge density distribution shows that the carbon atom forms covalent bonds with its three nearest neighbourhood. The spontaneous magnetization survives the curvature effect in BN nanotubes, suggesting the possibility of molecular magnets made from BN. Compared to other theoretical models of light-element or metal-free magnetic materials, the carbon-doped BN are more experimentally accessible and can be potentially useful.Comment: 8 pages, 4 figure

Dynamic Sensing Performance of a Point-Wise Fiber Bragg Grating Displacement Measurement System Integrated in an Active Structural Control System

In this work, a fiber Bragg grating (FBG) sensing system which can measure the transient response of out-of-plane point-wise displacement responses is set up on a smart cantilever beam and the feasibility of its use as a feedback sensor in an active structural control system is studied experimentally. An FBG filter is employed in the proposed fiber sensing system to dynamically demodulate the responses obtained by the FBG displacement sensor with high sensitivity. For comparison, a laser Doppler vibrometer (LDV) is utilized simultaneously to verify displacement detection ability of the FBG sensing system. An optical full-field measurement technique called amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI) is used to provide full-field vibration mode shapes and resonant frequencies. To verify the dynamic demodulation performance of the FBG filter, a traditional FBG strain sensor calibrated with a strain gauge is first employed to measure the dynamic strain of impact-induced vibrations. Then, system identification of the smart cantilever beam is performed by FBG strain and displacement sensors. Finally, by employing a velocity feedback control algorithm, the feasibility of integrating the proposed FBG displacement sensing system in a collocated feedback system is investigated and excellent dynamic feedback performance is demonstrated. In conclusion, our experiments show that the FBG sensor is capable of performing dynamic displacement feedback and/or strain measurements with high sensitivity and resolution

A 2-D π–π dimer model system to investigate structure-charge transfer relationships in rubrene

© The Royal Society of Chemistry 2019Rubrene (5,6,11,12-tetraphenyltetracene) is undoubtedly one of the best performing organic charge transfer mediating materials, with experimentally determined mobilities up to 40 cm2 V−1 s−1. Consequently, there has been increasing interest by means of crystal engineering in trying to generate rubrene-based materials with analogous or even superior conducting properties. Often, experimental measurements are carried out in thin film architectures of these materials, where measured properties can be detrimentally impacted by device manufacture rather than intrinsic charge transfer properties of the material. The latter results in discarding potential good performers. To address these concerns, we report a two-dimensional model system that will allow researchers to predict charge transfer properties of their materials solely requiring the coordinates of the π–π stacking motifs. We envisaged this study to be of significant interest to the increasingly large community of materials scientists devoted to the realisation of improved organic charge mediating materials and particularly to those engaged in exploiting rubrene-based architectures.Peer reviewedFinal Accepted Versio

Successful closed manipulation of a pure lateral traumatic dislocation of the elbow joint using a modified Stimson's technique: a case report

<p>Abstract</p> <p>Introduction</p> <p>Pure lateral elbow dislocation is rare, and a successful closed reduction is even rarer. Reduction can be hindered by swelling, soft tissue interposition or associated fractures.</p> <p>Case presentation</p> <p>We present a pure lateral traumatic dislocation of the elbow joint in a 40-year-old man. This was successfully manipulated and reduced in casualty using a modification of the gravity-aided 'hanging arm' technique originally described for shoulder dislocations by Stimson.</p> <p>Conclusion</p> <p>We strongly recommend the use of this simple technique in these rare yet difficult injuries, in order to avoid potential complications with general anaesthesia and surgery.</p

Technical Letter Report: Evaluation and Analysis of a Few International Periodic Safety Review Summary Reports

At the request of the United States (U.S.) government, the International Atomic Energy Agency (IAEA) assembled a team of 20 senior safety experts to review the regulatory framework for the safety of operating nuclear power plants in the United States. This review focused on the effectiveness of the regulatory functions implemented by the NRC and on its commitment to nuclear safety and continuous improvement. One suggestion resulting from that review was that the U.S. Nuclear Regulatory Commission (NRC) incorporate lessons learned from periodic safety reviews (PSRs) performed in other countries as an input to the NRC’s assessment processes. In the U.S., commercial nuclear power plants (NPPs) are granted an initial 40-year operating license, which may be renewed for additional 20-year periods, subject to complying with regulatory requirements. The NRC has established a framework through its inspection, and operational experience processes to ensure the safe operation of licensed nuclear facilities on an ongoing basis. In contrast, most other countries do not impose a specific time limit on the operating licenses for NPPs, they instead require that the utility operating the plant perform PSRs, typically at approximately 10-year intervals, to assure continued safe operation until the next assessment. The staff contracted with Argonne National Laboratory (Argonne) to perform a pilot review of selected translated PSR assessment reports and related documentation from foreign nuclear regulatory authorities to identify any potential new regulatory insights regarding license renewal-related topics and NPP operating experience (OpE). A total of 14 PSR assessment documents from 9 countries were reviewed. For all of the countries except France, individual reports were provided for each of the plants reviewed. In the case of France, three reports were provided that reviewed the performance assessment of thirty-four 900-MWe reactors of similar design commissioned between 1978 and 1988. All of the reports reviewed were the regulator’s assessment of the PSR findings rather than the original PSR report, and all but one were English translations from the original language. In these reviews, it was found that most of the countries base their regulatory guidance to some extent (and often to a large extent) on U.S. design codes and standards, NRC regulatory guidance, and U.S. industry guidance. In addition, many of the observed operational technical issues and OpE events reported for U.S. reactors are also cited in the PSR reports. The PSR reports also identified a number of potential technical material/component performance issues and OpE events that are not commonly reported for U.S. plants

Summary of technical information and agreements from Nuclear Management and Resources Council industry reports addressing license renewal

In about 1990, the Nuclear Management and Resources Council (NUMARC) submitted for NRC review ten industry reports (IRs) addressing aging issues associated with specific structures and components of nuclear power plants ad one IR addressing the screening methodology for integrated plant assessment. The NRC staff had been reviewing the ten NUMARC IRs; their comments on each IR and NUMARC responses to the comments have been compiled as public documents. This report provides a brief summary of the technical information and NUMARC/NRC agreements from the ten IRs, except for the Cable License Renewal IR. The technical information and agreements documented herein represent the status of the NRC staffs review when the NRC staff and industry resources were redirected to address rule implementation issues. The NRC staff plans to incorporate appropriate technical information and agreements into the draft standard review plan for license renewal

Gallbladder agenesis diagnosed intra-operatively: a case report

<p>Abstract</p> <p>Introduction</p> <p>Agenesis of the gallbladder is a rare congenital anomaly occurring in 13 to 65 people of a population of 100,000. The rarity of the condition, combined with clinical and radiologic features that are indistinguishable from those of more common biliary conditions, means that it is rarely diagnosed preoperatively, and patients undergo unnecessary operative intervention.</p> <p>Case presentation</p> <p>This case report describes the case of a 79-year-old symptomatic Caucasian man who underwent laparoscopic cholecystectomy for suspected choledocholithiasis despite imaging studies raising suspicion of gallbladder agenesis. Intra-operatively, the diagnosis of gallbladder agenesis and associated common bile duct stones was made.</p> <p>Conclusion</p> <p>The preoperative diagnosis of this rare condition is difficult to make. However, with advances in biliary tract imaging and with heightened awareness of this anomaly, fewer patients will need to undergo unnecessary operative intervention. The authors review the different imaging modalities available to help diagnose this condition and highlight the importance of being aware of this rare anomaly to avoid an operation that carries a high risk of iatrogenic injury.</p

Improving Cancer Classification Accuracy Using Gene Pairs

Recent studies suggest that the deregulation of pathways, rather than individual genes, may be critical in triggering carcinogenesis. The pathway deregulation is often caused by the simultaneous deregulation of more than one gene in the pathway. This suggests that robust gene pair combinations may exploit the underlying bio-molecular reactions that are relevant to the pathway deregulation and thus they could provide better biomarkers for cancer, as compared to individual genes. In order to validate this hypothesis, in this paper, we used gene pair combinations, called doublets, as input to the cancer classification algorithms, instead of the original expression values, and we showed that the classification accuracy was consistently improved across different datasets and classification algorithms. We validated the proposed approach using nine cancer datasets and five classification algorithms including Prediction Analysis for Microarrays (PAM), C4.5 Decision Trees (DT), Naive Bayesian (NB), Support Vector Machine (SVM), and k-Nearest Neighbor (k-NN)

Managing aging effects on dry cask storage systems for extended long-term storage and transportation of used fuel - rev. 0

The cancellation of the Yucca Mountain repository program in the United States raises the prospect of extended long-term storage (i.e., &gt;120 years) and deferred transportation of used fuel at operating and decommissioned nuclear power plant sites. Under U.S. federal regulations contained in Title 10 of the Code of Federal Regulations (CFR) 72.42, the initial license term for an Independent Spent Fuel Storage Installation (ISFSI) must not exceed 40 years from the date of issuance. Licenses may be renewed by the U.S. Nuclear Regulatory Commission (NRC) at the expiration of the license term upon application by the licensee for a period not to exceed 40 years. Application for ISFSI license renewals must include the following: (1) Time-limited aging analyses (TLAAs) that demonstrate that structures, systems, and components (SSCs) important to safety will continue to perform their intended function for the requested period of extended operation; and (2) a description of the aging management program (AMP) for management of issues associated with aging that could adversely affect SSCs important to safety. In addition, the application must also include design bases information as documented in the most recent updated final safety analysis report as required by 10 CFR 72.70. Information contained in previous applications, statements, or reports filed with the Commission under the license may be incorporated by reference provided that those references are clear and specific. The NRC has recently issued the Standard Review Plan (SRP) for renewal of used-fuel dry cask storage system (DCSS) licenses and Certificates of Compliance (CoCs), NUREG-1927, under which NRC may renew a specific license or a CoC for a term not to exceed 40 years. Both the license and the CoC renewal applications must contain revised technical requirements and operating conditions (fuel storage, surveillance and maintenance, and other requirements) for the ISFSI and DCSS that address aging effects that could affect the safe storage of the used fuel. The information contained in the license and CoC renewal applications will require NRC review to verify that the aging effects on the SSCs in DCSSs/ ISFSIs are adequately managed for the period of extended operation. To date, all of the ISFSIs located across the United States with more than 1,500 dry casks loaded with used fuel have initial license terms of 20 years; three ISFSIs (Surry, H.B. Robinson and Oconee) have received their renewed licenses for 20 years, and two other ISFSIs (Calvert Cliffs and Prairie Island) have applied for license renewal for 40 years. This report examines issues related to managing aging effects on the SSCs in DCSSs/ISFSIs for extended long-term storage and transportation of used fuels, following an approach similar to that of the Generic Aging Lessons Learned (GALL) report, NUREG-1801, for the aging management and license renewal of nuclear power plants. The report contains five chapters and an appendix on quality assurance for aging management programs for used-fuel dry storage systems. Chapter I of the report provides an overview of the ISFSI license renewal process based on 10 CFR 72 and the guidance provided in NUREG-1927. Chapter II contains definitions and terms for structures and components in DCSSs, materials, environments, aging effects, and aging mechanisms. Chapter III and Chapter IV contain generic TLAAs and AMPs, respectively, that have been developed for managing aging effects on the SSCs important to safety in the dry cask storage system designs described in Chapter V. The summary descriptions and tabulations of evaluations of AMPs and TLAAs for the SSCs that are important to safety in Chapter V include DCSS designs (i.e., NUHOMS{reg_sign}, HI-STORM 100, Transnuclear (TN) metal cask, NAC International S/T storage cask, ventilated storage cask (VSC-24), and the Westinghouse MC-10 metal dry storage cask) that have been and continue to be used by utilities across the country for dry storage of used fuel to date. The goal of this report is to help establish the technical basis for extended long-term storage and transportation of used fuel