Enhanced Safety Features Research Articles

The Quantum Car

I explore the use of quantum information as a security enabler for the future driverless vehicle. Specifically, I investigate the role combined classical and quantum information can have on the most important characteristic of the driverless vehicle paradigm - the vehicle location. By using information-theoretic verification frameworks, coupled with emerging quantum-based location-verification procedures, I show how vehicle positions can be authenticated with a probability of error simply not attainable in classical-only networks. I also discuss how other quantum applications can be seamlessly encapsulated within the same vehicular communication infrastructure required for location verification. The two technology enablers required for the driverless quantum vehicle are an increase in current quantum memory timescales (likely) and wide-scale deployment of classical vehicular communication infrastructure (underway). I argue the enhanced safety features delivered by the `Quantum Car' mean its eventual deployment is inevitable.

Assessment of passive safety system of a Small Modular Reactor (SMR)

Innovative SMRs are designed with enhanced safety features based on lessons learnt from past experience of plant operation. Reliance on natural circulation and addition of passive safety systems made them inherently safe and simple in design. It is required to study reliability assessment of passive safety systems during postulated transients prior to their deployment on commercial scale. Test facilities and best estimate system codes are playing significant role in assessment of passive safety systems as well as in design, certification and evaluation of these innovative types of reactors. RELAP5 code is widely used for thermal-hydraulic analysis of nuclear reactors. In this work, the passive safety systems of Multi-Application Small Light Water (MASLWR) have been assessed. The complete loop of the MASLWR test facility has been modeled in RELAP5-SCDAP Mod 4.0. The RELAP5 model is validated by comparing the simulation results with the experimental data. Results obtained for various transients show that high pressure vent and sump recirculation lines provide natural circulation flow path for long term cooling of core to avoid core heat up.Some of the components of passive safety system of MASLWR still rely on active power. Therefore, it was necessary to investigate their performance under failure of these components. New scenarios are considered in which the effect of vent and sump recirculation valves failure has been investigated in the present work. It is found from the results that continuous loss of inventory occurs due to lack of recirculation. It is thus concluded from this study that the high pressure vent valves in the MASLWR safety system require more redundancy.

Gene Transfer Strategies to Promote Chondrogenesis and Cartilage Regeneration.

Gene transfer has been used experimentally to promote chondrogenesis and cartilage regeneration. While it is controversial to apply gene therapy for nonlethal conditions such as cartilage defect, there is a possibility that the transfer of therapeutic transgenes may dramatically increase the effectiveness of cell therapy and reduce the quantity of cells that are needed to regenerate cartilage. Single or combination of growth factors and transcription factors has been transferred to mesenchymal stem cells or articular chondrocytes using both nonviral and viral approaches. The current challenge for the clinical applications of genetically modified cells is ensuring the safety of gene therapy while guaranteeing effectiveness. Viral gene delivery methods have been mainstays currently with enhanced safety features being recently refined. On the other hand, efficiency has been greatly improved in nonviral delivery. This review summarizes the history and recent update on the gene transfer to enhance chondrogenesis from stem cells or articular chondrocytes.

Enhanced Safety Features in Motor Control Centers and Drives for Diagnostics and Troubleshooting

It is common practice in the industry for electrical workers to be exposed to shock and arc blast and arc flash hazards as they perform routine maintenance and diagnostic testing on equipment enclosed in motor control centers (MCCs). This paper will illustrate the influence that various IEEE conferences, including the Electrical Safety Workshop, has had on changing the electrical safety culture related to equipment diagnostics. End users are now requesting manufacturers of low- and medium-voltage MCCs to develop or add features and functionality into their products that enhance the ability of electrical maintenance and operating personnel to conduct routine diagnostic and troubleshooting tasks without being directly exposed to energized electrical equipment. This paper will explore some of these features and provide some examples of routine maintenance and diagnostic tasks that can be performed while doing troubleshooting and diagnostic tasks on operating equipment without opening enclosure doors and exposing workers to the hazards associated with exposed energized equipment.

Modular minimally invasive extracorporeal circulation systems; can they become the standard practice for performing cardiac surgery?

Minimally invasive extracorporeal circulation (MiECC) has been developed in an attempt to integrate all advances in cardiopulmonary bypass technology in one closed circuit that shows improved biocompatibility and minimizes the systemic detrimental effects of CPB. Despite well-evidenced clinical advantages, penetration of MiECC technology into clinical practice is hampered by concerns raised by perfusionists and surgeons regarding air handling together with blood and volume management during CPB. We designed a modular MiECC circuit, bearing an accessory circuit for immediate transition to an open system that can be used in every adult cardiac surgical procedure, offering enhanced safety features. We challenged this modular circuit in a series of 50 consecutive patients. Our results showed that the modular AHEPA circuit design offers 100% technical success rate in a cohort of random, high-risk patients who underwent complex procedures, including reoperation and valve and aortic surgery, together with emergency cases. This pilot study applies to the real world and prompts for further evaluation of modular MiECC systems through multicentre trials.

Demand for safety and regional certification of food

Purpose– This paper aims to explore the relationship between consumer demand for enhanced food safety features and regional identification of food amongst consumers across Great Britain and the Republic of Ireland.Design/methodology/approach– The paper uses the choice experiment method to determine preferences for food testing standards, traceability standards, health and welfare standards, region of origin and price.Findings– The results show that substantial differences exist in preferences for the features between consumers in both countries. In addition, while stark differences are apparent between the two countries, in their preferences for food originating from their local region, the results suggest that consumers perceive significant substitutability between the enhanced safety features and the local regional label in both countries.Originality/value– This paper provides a unique insight into preferences for a wide range of enhanced food safety features amongst consumers in these two countries. This is the first study to undertake a comparison of these countries using the choice experiment method. In addition, the paper provides a thorough overview of how consumers perceive the relationship between enhanced safety features and region of origin of food.

User Acceptance of a Light-Emitting Diode Vest for Police Officer

This study aims to suggest practical considerations for designing protective clothing with increased visibility that will have higher user acceptance by law enforcement officers. Light-emitting diode(LED) patrol vests were visually and structurally assessed, and 125 police officers' responses from surveys about user acceptance of the vest were analyzed. The current LED patrol vest was designed for enhanced safety of police officers by increasing visibility in the dark. However, the user acceptance rate of the LED patrol vest indicates low use of and low satisfaction with the vest despite its enhanced safety features. In particular, differences in materials, design, functionality of the pockets and size of the vest depending on the hours worked, were statistically significant. The police officers' responses suggest areas of improvement in design, materials, ease of movement, size and functionality. Key issues include 'tactile discomfort'; 'impeded vision from the glare of the LED'; 'frequent malfunctions of the LED'; 'impossible repair of the broken LED units'; 'no user feedback'; 'inconvenient to replace batteries'; 'brittle materials' and 'unpleasing look'. To increase user acceptance, designer should incorporate context-awareness, a convenient user interface, a modular design approach, first responders' self-image as public servants in relation to their aesthetic perspectives of their uniforms, and scientific evaluation of the effectiveness of the intended functions of the clothing. Suggested implications for designing the LED patrol vest can be applied to designing other functional/protective clothing for intended end users with special needs.

Core safety of Indian nuclear power plants (NPPs) under extreme conditions

Nuclear power is currently the fourth largest source of electricity production in India after thermal, hydro and renewable sources of electricity. Currently, India has 20 nuclear reactors in operation and seven other reactors are under construction. Most of these reactors are indigenously designed and built Heavy Water Reactors. In addition, a 300 MWe Advanced Heavy Water Reactor has already been designed and in the process of deployment in near future for demonstration of power production from Thorium apart from enhanced safety features by passive means. India has ambitious plans to enhance the share of electricity production from nuclear. The recent Fukushima accident has raised concerns of safety of Nuclear Power Plants worldwide. The Fukushima accident was caused by extreme events, i.e., large earthquake followed by gigantic Tsunami which are not expected to hit India’s coast considering the geography of India and historical records. Nevertheless, systematic investigations have been conducted by nuclear scientists in India to evaluate the safety of the current Nuclear Power Plants in case of occurrence of such extreme events in any nuclear site. This paper gives a brief outline of the safety features of Indian Heavy Water Reactors for prevention and mitigation of such extreme events. The probabilistic safety analysis revealed that the risk from Indian Heavy Water Reactors are negligibly small.

Thermal Hydraulics of Sodium-Cooled Fast Reactors: Key Design and Safety Issues and Highlights

This paper discusses key issues and highlighted topics in thermal hydraulics in connection with Japan’s current sodium-cooled fast reactor development efforts, with particular focus on design study and related research of the Japan Sodium-Cooled Fast Reactor (JSFR). Several innovative technologies, i.e., compact reactor vessel, two-loop system, full natural-circulation decay heat removal, and recriticality-free core, have been investigated to reduce construction cost and to achieve a high level of reactor safety. Preliminary evaluations of innovative technologies to be applied to JSFR are ongoing. In this paper, the progress of design study is reviewed, and key issues are discussed. Then, research and development activities on the thermal hydraulics are highlighted in connection with the phenomena taking place in natural-circulation decay heat removal and innovative design and enhanced safety features.

A new design concept for offshore nuclear power plants with enhanced safety features

In this paper, we present a new concept for offshore nuclear power plants (ONPP) with enhanced safety features. The design concept of a nuclear power plant (NPP) mounted on gravity-based structures (GBSs), which are widely used offshore structures, is proposed first. To demonstrate the feasibility of the concept, a large-scale land-based nuclear power plant model APR1400, which is the most recent NPP model in the Republic of Korea, is mounted on a GBS while minimizing modification to the original features of APR1400. A new total general arrangement (GA) and basic design principles are proposed and can be directly applied to any existing land based large scale NPPs. The proposed concept will enhance the safety of a NPP due to several aspects. A new emergency passive containment cooling system (EPCCS) and emergency passive reactor-vessel cooling system (EPRVCS) are proposed; their features of using seawater as coolant and safety features against earthquakes, Tsunamis, storms, and marine collisions are also described. We believe that the proposed offshore nuclear power plant is more robust than conventional land-based nuclear power plants and it has strong potential to provide great opportunities in nuclear power industries by decoupling the site of construction and that of installation.

An innovative pool with a passive heat removal system

Heat removal systems are of primary importance in several industrial processes. As heat sink, a water pool or atmospheric air may be selected. The first solution takes advantage of high heat transfer coefficient with water but it requires active systems to maintain a constant water level; the second solution takes benefit from the unlimited heat removal capacity by air, but it requires a larger heat exchanger to compensate the lower heat transfer coefficient. In NPPs (nuclear power plants) during a nuclear reactor shutdown, as well as in some chemical plants to control runaway reactions, it is possible to use an innovative heat sink that joins the advantages of the two previous solutions. This solution is based on a special heat exchanger submerged in a water pool designed so that when heat removal is requested, active systems are not required to maintain the water level; due to the special design, when the pool is empty, atmospheric air becomes the only heat sink. The special heat exchanger design allows to have a heat exchanger without being oversized and to have a system able to operate for unlimited period without external interventions. This innovative system provides an economic advantage as well as enhanced safety features.

Trimming- and pruning-related injuries in the United States, 1990 to 2007

Trimming and pruning equipment is used frequently in the United States, and associated injuries are common. The National Electronic Injury Surveillance System database was used to examine trimming- and pruning-related injuries treated in US hospital emergency departments from 1990 through 2007. An estimated 648,100 individuals (95% confidence interval: 535,500-760,700) were treated in US hospital emergency departments for trimming- and pruning-related injuries during the 18-year study period. The average annual injury rate was 13.0 per 100,000 US population, and the annual rate of injury increased 35.1% from 11.4 in 1990 to 15.4 in 2007 (slope = 0.241, p < 0.01). Approximately two-thirds (67.6%) of the injuries occurred among males, and 62.8% of incidents occurred to individuals 18 years to 54 years of age. Lacerations and puncture injuries occurred most often (71.0%), and injuries to the arms and hands accounted for 67.8% of cases. A majority (56.8%) of injuries involved the use of a power tool. The most common project at the time of injury was hedge/shrub trimming (66.5%), followed by grass/lawn trimming (24.3%) and tree trimming (9.1%). Patients required hospitalization in 2.1% of cases. Most injury incidents (98.5%) occurred around the home. This is the first study to examine trimming- and pruning-related injuries in the United States using a nationally representative sample. The increasing number and rate of injuries associated with trimming activities in the United States underscore the need for increased prevention efforts, including enhanced safety features of trimming equipment and better education of equipment operators regarding the potential hazards of trimming activities.

Baculoviruses deficient in ie1 gene function abrogate viral gene expression in transduced mammalian cells

One of the newest niches for baculoviruses-based technologies is their use as vectors for mammalian cell transduction and gene therapy applications. However, an outstanding safety issue related to such use is the residual expression of viral genes in infected mammalian cells. Here we show that infectious baculoviruses lacking the major transcriptional regulator, IE1, can be produced in insect host cells stably transformed with IE1 expression constructs lacking targets of homologous recombination that could promote the generation of wt-like revertants. Such ie1-deficient baculoviruses are unable to direct viral gene transcription to any appreciable degree and do not replicate in normal insect host cells. Most importantly, the residual viral gene expression, which occurs in mammalian cells infected with wt baculoviruses is reduced 10 to 100 fold in cells infected with ie1-deficient baculoviruses. Thus, ie1-deficient baculoviruses offer enhanced safety features to baculovirus-based vector systems destined for use in gene therapy applications.

HTR's role in process heat applications

Advanced high-temperature nuclear reactors create a number of new opportunities for nuclear process heat applications. These opportunities are based on the high-temperature heat available, smaller reactor sizes, and enhanced safety features that allow siting close to process plants. Major sources of value include the displacement of premium fuels and the elimination of CO 2 emissions from combustion of conventional fuels and their use to produce hydrogen. High value applications include steam production and cogeneration, steam methane reforming, and water splitting. Market entry by advanced high-temperature reactor technology is challenged by the evolution of nuclear licensing requirements in countries targeted for early applications, by the development of a customer base not familiar with nuclear technology and related issues, by convergence of oil industry and nuclear industry risk management, by development of public and government policy support, by resolution of nuclear waste and proliferation concerns, and by the development of new business entities and business models to support commercialization. New HTR designs may see a larger opportunity in process heat niche applications than in power given competition from larger advanced light water reactors. Technology development is required in many areas to enable these new applications, including the commercialization of new heat exchangers capable of operating at high temperatures and pressures, convective process reactors and suitable catalysts, water splitting system and component designs, and other process-side requirements. Key forces that will shape these markets include future fuel availability and pricing, implementation and monetization of CO 2 emission limits, and the formation of international energy and environmental policy that will support initiatives to provide the nuclear licensing frameworks and risk distribution needed to support private investment. This paper was developed based on a plenary session presentation at HTR-2006 which won Best Paper.

A NOVEL MANIPULATOR FOR PROSTATE BRACHYTHERAPY: DESIGN AND PRELIMINARY RESULTS

The prostate is a small exocrine gland in men responsible for production of the liquid component of the seminal fluid. In North America, prostate cancer accounts to over 300,000 new cases and 40,000 deaths each year and it is the second leading cause of cancer death in men. Low-dose Rate (LDR) brachytherapy is gaining interest as a viable treatment option for prostate cancer due to its low side effects and high benefits. This procedure involves insertion of small seeds of radioactive isotopes into the gland to effect radiation therapy. The present manual approach for needle insertion and the inherent flexibility of brachytherapy needles makes it extremely difficult to achieve accurate and consistent dosimetry. In this paper, we present the design of a new 5 DOF manipulator capable of performing percutaneous needle insertion. The manipulator can perform orientation, insertion and rotation of the needle and linear motion of the plunger to drop radioactive seeds at targeted locations. Some of the key features of the manipulator are backdrivable joints, stationary actuators, redundant sensors and enhanced safety features. The manipulator will become an integral part of a system utilizing real-time 3D ultrasound image guided prostate brachytherapy. In this paper, we describe the mechanical design, construction and assembly of the manipulator.

Use of failure mode and effects analysis in improving the safety of i.v. drug administration

Failure mode and effects analysis (FMEA) was used to identify dosing and administration errors associated with i.v. medications and evaluate the effectiveness of subsequent system improvements. A multidisciplinary medication safety team conducted an FMEA to identify and reduce common medication errors and selected wrong-dose errors for process improvement. In 2002, wrong-dose errors comprised 17% of all medication errors at the hospital (59 of 347 errors). The most common reason for administering the wrong dose was error in programming the i.v. infusion pump (41%). Potential errors (i.e., failures) identified were misinterpretation of the order, removing the wrong medication or wrong concentration of the correct medication, using the wrong diluent or drug to prepare the drip, and entering the wrong concentration or infusion rate on the pump. Errors in programming the i.v. infusion pump was the step in the medication-use process associated with the highest criticality index. Based on the results of the FMEA, two main interventions were performed. First, standard order sets were revised after streamlining the formulary and eliminating the use of unapproved abbreviations. Second, an i.v. pump with enhanced safety features was implemented. One-year follow-up data revealed that the number of medication errors related to dosing (wrong dose or incorrect infusion rate) had decreased slightly (from 59 in 2002 to 46 in 2003); however, a dramatic reduction was noted in the percentage of pump-related errors. In 2003, pump-related errors accounted for 22% of dosing errors, compared with 41% in 2002. Medication errors related to i.v. infusion pumps were reduced by conducting an FMEA and implementing the process changes needed.

476. HIV-1 and HIV-2 Chimeric Lentiviral Vectors for Gene Transfer

To more fully exploit the translational potential of lentiviral vectors, three issues must be addressed: regulation, safety, and targeting. One major concern of safety is the possibility of recombination events generating replication competent virus, be that in the laboratory during vector production and in the clinic for gene transfer with patients who might be infected with HIV. We describe here our efforts to enhance safety without sacrificing efficiency of transduction. We start with the premise that the genetic sequences of HIV-1 and HIV-2 are dissimilar enough not to engage in recombination, yet similar enough to functionally complement. Thus, we are creating chimeric or hybrid vectors between HIV-1 and HIV-2 by knowledge-based exchanges of genes and subgenic regions. Cross packaging experiments showed that with the HIV-1 'wild type' packaging construct, the titer (TU/ml) of the vectors for both HIV-1 and HIV-2 vector RNA was approximately the same. However, with the 'wild type' HIV-2 packaging construct, the titer of HIV-2 vector RNA was higher than that of the HIV-1 vector RNA. This might imply that the requirements for recognition and packaging with HIV-2 packaging machinery were more stringent that with HIV-1 packaging machinery. To test that, we created chimeric packaging constructs where 5'-halfs and 3'-halfs of the packaging constructs were exchanged. With the chimeric HIV-2 packaging construct where its 'gag-pol' segment was replaced with the corresponding HIV-1 segment, the titer of the HIV-1 vector improved and that of the HIV-2 vector declined, as compared with the 'wild type' HIV-2 packaging constructs. There was much less change in the titer with the chimeric HIV-2 packaging construct when the 'tat-rev' region was exchanged. Though in need of further dissection, these observations may be consistent with idea of the importance of Gag in recognition and encapsidation. Serial passage of the vector supernatants of HIV-1 or HIV-2 vectors packaged with the wild type or chimeric packaging constructs gave no evidence for recombination; after the first passage, no transgene expression was observed. Though preliminary, the results support the idea that chimeric or hybrid vectors can be created with enhanced safety features without loss of effectiveness.

A perspective on fast reactor fuel cycle in India

The growing energy needs of India can be fulfilled only by judicious mix of all the fuel resources. It is possible to achieve energy security and sustainability through the introduction of fast reactors in an expeditious manner and closing the fuel cycle. This approach is inevitable in view of the limited uranium resources in India. The Fast Breeder Test Reactor (FBTR) built by India uses mixed carbide as fuel and the 500 MW(e) Fast Breeder Reactor Project (PFBR), to be operational in 2010, will use mixed oxide as fuel. It has also been decided that fast reactors beyond 2020, with enhanced safety features and having better economy, will use metallic fuel. Having successfully operated FBTR with carbide fuels, we need to develop the fuel cycles for both the mixed oxide fuel in the near future and the metallic fuel expeditiously. The progress achieved so far and the plans for implementation are discussed in this paper.

68. Improved lentiviral vector system with enhanced safety features

Top of pageAbstract The traditional method for producing self-inactivating lentiviral stocks has been the three/four plasmid transient transfection method. However, employing packaging cell lines to produce lentiviral vector stocks may circumvent inconsistencies in vector stocks and efficacy, and improve vector safety by reducing the risk of generating replication competent virus. Developing a safe HIV-based packaging cell line has been hindered by the inability to rescue self-inactivating (SIN) or Tat-independent vectors used to transduce the packaging cell line in the final steps of its production. EIAV- and FIV-based vectors would appear to be advantageous in this regard since they retain a fully functional LTR, however the activity of their LTR is considerably abated in human cells. The ability to thwart these problems has been accomplished through the development of tetracycline-dependent packaging cell lines. These cell lines have provided a platform upon which to generate conditional SIN (cSIN) lentiviral vectors in a stable, reproducible manner. Beginning with the SODk0 cell line we have generated a tetracycline-dependent packaging cell line containing the vesicular stomatitis virus glycoprotein (VSV-G) envelope, the split gag-pro and vpr-pol packaging cassettes, and a cSIN vector all under control of the tetracycline response element. Aspiring to generate vector titers equivalent to those yielded by the transient transfection methods (>107 IU/mL) revealed factors that influence the vector titers during the development of a lentiviral vector packaging cell line. Through clonal selection we demonstrate that doxycycline (Dox)-dependent control of the tetracycline transactivator (tTA), the ratio of Gag-Pol proteins, and integration of a cSIN vector into the genome exhibit cell-to-cell differences which have an impact on vector titers. A detailed assessment of multiple cell clones resulted in the generation of a packaging cell line yielding vector titers in excess of 106 IU/mL. Anticipating a need for large-scale lentiviral vector production for gene therapy clinical trials necessitates further improvements in packaging cell lines for lentiviral vector production. In our efforts to advance packaging cell lines we are currently examining the use of alternative approaches to introduce SIN vectors into the packaging cell line, thus circumventing the need to transduce the packaging cell line with a cSIN vector.

Performance of sub-atmospheric pressure hydride gas source and delivery system for MOCVD

A sub-atmospheric pressure gas enhanced (SAGE™) arsine source and delivery system has been evaluated and found to meet the flow rate and gas purity requirements of metal-organic chemical vapor deposition (MOCVD) processes. Gas delivery at 80 kPa and with flow rates up to 10 slpm have been accomplished using a specially developed extractor unit. AlGaAs double hetero structures grown with SAGE and high-pressure (HP) arsine sources have been characterized by secondary ion mass spectrometry (SIMS) to verify gas purity. SAGE arsine was found to be equivalent to the HP arsine reference, with regard to oxygen incorporation, provided the recommended SAGE delivery system startup procedures were adhered to. Cylinder depletion studies also showed that the moisture concentration in SAGE arsine slowly decreases over the cylinder lifetime, whereas in HP arsine, it rises as the last third of the cylinder is consumed. These findings, together with the enhanced safety features and potential for scale up, make SAGE technology particularly attractive for routine production of commercial devices.