bluuebunny/crossref_metadata_2025 huggingface dataset:
Status of duckweed genomics and transcriptomics
Authors: Wang W. , Messing J.
Published: July 2014

Duckweeds belong to the smallest flowering plants that undergo fast vegetative growth in an aquatic environment. They are commonly used in wastewater treatment and animal feed. Whereas duckweeds have been studied at the biochemical level, their reduced morphology and wide environmental adaption had not been subjected to molecular analysis until recently. Here, we review the progress that has been made in using a DNA barcode system and the sequences of chloroplast and mitochondrial genomes to identify duckweed species at the species or population level. We also review analysis of the nuclear genome sequence of Spirodela that provides new insights into fundamental biological questions. Indeed, reduced gene families and missing genes are consistent with its compact morphogenesis, aquatic floating and suppression of juvenile‐to‐adult transition. Furthermore, deep RNA sequencing of Spirodela at the onset of dormancy and Landoltia in exposure of nutrient deficiency illustrate the molecular network for environmental adaption and stress response, constituting major progress towards a post‐genome sequencing phase, where further functional genomic details can be explored. Rapid advances in sequencing technologies could continue to promote a proliferation of genome sequences for additional ecotypes as well as for other duckweed species.
Pollen transfer efficiency and its effect on inflorescence size in deceptive pollination strategies
Authors: Scopece G. , Schiestl F. P. , Cozzolino S.
Published: July 2014

Pollination systems differ in pollen transfer efficiency, a variable that may influence the evolution of flower number. Here we apply a comparative approach to examine the link between pollen transfer efficiency and the evolution of inflorescence size in food and sexually deceptive orchids. We examined pollination performance in nine food‐deceptive, and eight sexually deceptive orchids by recording pollen removal and deposition in the field. We calculated correlations between reproductive success and flower number (as a proxy for resources allocated during reproductive process), and directional selection differentials were estimated on flower number for four species. Results indicate that sexually deceptive species experience decreased pollen loss compared to food‐deceptive species. Despite producing fewer flowers, sexually deceptive species attained levels of overall pollination success (through male and female function) similar to food‐deceptive species. Furthermore, a positive correlation between flower number and pollination success was observed in food‐deceptive species, but this correlation was not detected in sexually deceptive species. Directional selection differentials for flower number were significantly higher in food compared to sexually deceptive species. We suggest that pollination systems with more efficient pollen transfer and no correlation between pollination success and number of flowers produced, such as sexual deception, may allow the production of inflorescences with fewer flowers that permit the plant to allocate fewer resources to floral displays and, at the same time, limit transpiration. This strategy can be particularly important for ecological success in Mediterranean water‐deprived habitats, and might explain the high frequency of sexually deceptive species in these specialised ecosystems.
Roles of Ki‐67, p53, transforming growth factor‐β and lysyl oxidase in the metastasis of lung cancer
Authors: Araz Omer , Demirci Elif , Yilmazel Ucar Elif , Calik Muhammet , Karaman Adem , Durur‐Subasi Irmak , Orsal Ebru , Subasi Mahmut , Daloglu Ferah , Akgun Metin
Published: July 2014

Background and objective

Most lung cancer (LC) patients have metastatic disease at time of diagnosis, which influence the treatment regimen and is the most important prognostic factor. The main purpose of our study was to evaluate the relationship between cell proliferation (Ki‐67 label index), p53, transforming growth factor‐β (TGF‐β) and lysyl oxidase (LOX), and the metastatic stages of different lung cancers. The secondary aim was to correlate these parameters with the standardized uptake value (SUVmax) of the primary lesion during positron emission tomography‐computed tomography (PET‐CT).

Methods

Eighty‐five treatment‐naive patients with LC were enrolled. All patients were examined with PET‐CT. Ki‐67, p53, TGF‐β and LOX were evaluated histopathologically.

Results

Small cell lung cancer (SCLC) showed the most intense staining in all parameters. A well‐differentiated adenocarcinoma (AC) demonstrated a more diffuse and intense staining than squamous cell carcinoma (SCC). There was no statistically significant relationship between the four parameters and metastases of SCLC and SCC. However, a significant relationship between TGF‐β, LOX and metastatic AC was demonstrated with regards to diffusivity and intensity. p53 and Ki‐67 did not show a significant relationship. No correlation between SCLC and SCC and SUVmax was found. However, in AC, the diffusivity and intensity of the LOX and p53 staining showed a statistically significant relationship to the SUVmax.

Conclusions

LOX and TGF‐β may play roles in metastatic AC. LOX and TGF‐β may become markers of metastatic disease and inhibition could be explored for treatment.
Relationship between the baseline alveolar volume‐to‐total lung capacity ratio and airway responsiveness
Authors: Kaminsky David A. , Daud Anees , Chapman David G.
Published: July 2014

Background and objective

Ventilation heterogeneity (VH) has been linked to airway responsiveness (AR) based on various measures of VH involving inert gas washout, forced oscillation and lung imaging. We explore whether VH at baseline, as measured by the simple ratio of single breath alveolar volume to plethysmographically determined total lung capacity (VA/TLC), would correlate with AR as measured by methacholine challenge testing.

Methods

We analysed data from spirometry, lung volumes, diffusing capacity and methacholine challenge to derive the VA/TLC and the dose–response slope (DRS) of forced expiratory volume in 1 s (DRS‐FEV1) during methacholine challenge from 136 patients. We separated out airway closure versus narrowing by examining the DRS for forced vital capacity (DRS‐FVC) and the DRS for FEV1/FVC (DRS‐FEV1/FVC), respectively. Similarly, we calculated the DRS for sGaw (DRS‐sGaw) as another measure of airway narrowing. We performed statistical analysis using Spearman rank correlation and multifactor linear regression using a backward stepwise modelling procedure.

Results

We found that the DRS‐FEV1 correlated with baseline VA/TLC (rho = −0.26, P < 0.01), and VA/TLC and FEV1 were independently associated with DRS‐FEV1 (R2 = 0.14, P = 0.01). In addition, VA/TLC was associated with both airway narrowing and closure in response to methacholine.

Conclusions

These results confirm that baseline VA/TLC is associated with AR, and reflects both airway closure and airway narrowing following methacholine challenge.
Supply Disruptions and Regional Price Effects in a Spatial Oligopoly—An Application to the Global Gas Market
Authors: Growitsch Christian , Hecking Harald , Panke Timo
Published: July 2014

Supply shocks in the global gas market may affect countries differently, as the market is regionally interlinked but not perfectly integrated. Additionally, high supply‐side concentration may expose countries to market power in different ways. To evaluate the strategic position of importing countries with regard to gas supplies, we disentangle the import price into different components and characterize each component as price increasing or price decreasing. Because of the complexity of the interrelations in the global gas market, we use an equilibrium model programmed as a mixed complementarity problem (MCP) and simulate the blockage of liquefied natural gas (LNG) flows through the Strait of Hormuz. This enables us to account for the oligopolistic nature and the asymmetry of the gas supply. We find that Japan faces the most severe price increases, as the Japanese gas demand completely relies on LNG supply. In contrast, European countries such as the UK benefit from good interconnection to the continental pipeline system and domestic price taking production, both of which help to mitigate an increase in physical costs of supply as well as in the exercise of market power.
Use and interpretation of test scores from limited cognitive test batteries: How g + Gc can equal g
Authors: Annell Stefan , Sjöberg Anders , Sverke Magnus
Published: July 2014

Single scores from limited and unbalanced test batteries of cognitive ability can be ambiguous to interpret theoretically. In this study, a limited verbally and knowledge‐loaded cognitive test battery, from applicants to the Swedish police academies (N = 1,344), was examined to provide foundations for the use and interpretation of test scores. Three measurement models were compared: one single factor model and two bifactor models, which decomposed the variance of the battery into orthogonal components. The models were evaluated by fit indices and omega coefficients, and then applied to the prediction of academic performance. The overall prediction of all models was similar, although specific abilities also were found to provide substantial predictive validity over and above general intelligence (g). The findings provide support for the use of single scores in applied settings (selection), but suggest that it may be more appropriate to interpret such scores as composites of substantive components, and not just as measures of g.
Judges' views of child sexual abuse: Evaluating beliefs against research findings in a Finnish sample
Authors: Korkman Julia , Svanbäck Jatta , Finnilä Katarina , Santtila Pekka
Published: July 2014

Beliefs impact our decision‐making and different professionals have been shown to have beliefs about child sexual abuse (CSA) that do not coincide with scientific findings. In the present study, judges' beliefs regarding CSA were explored. Finnish judges (N = 104) answered a questionnaire about CSA related issues as well as questions regarding their professional experience of CSA cases. The judges held both correct and incorrect beliefs; while their CSA prevalence estimates were rather well in line with research findings, half of the participants estimated that no professionals use suggestive methods when interviewing children and more than 40% thought suggestive methods can be useful when trying to get a child to tell about real events. Judges correctly assumed symptoms cannot be used to assess a CSA case, however, the majority thought play observations were appropriate means for evaluating such suspicions. Experience seemed to lead to more confidence in their own expertise but not in an actual increase in knowledge, namely, judges thought themselves more expert when more experienced although their expertise as measured by the questionnaire did not improve. Overall, the judges had both correct and erroneous beliefs but while experience did not improve the situation, gaining information about CSA did. More research about the beliefs of judges and how such beliefs impact legal decision‐making is needed.
The influences of sex and posture on joint energetics during drop landings
Authors: Norcross M. F. , Shultz S. J. , Weinhold P. S. , Lewek M. D. , Padua D. A. , Blackburn J. T.
Published: July 2014

Previous observations suggest that females utilize a more erect initial landing posture than males with sex differences in landing posture possibly related to sex‐specific energy absorption (EA) strategies. However, sex‐specific EA strategies have only been observed when accompanied by sex differences in initial landing posture. This study (a) investigated the potential existence of sex‐specific EA strategies; and (b) determined the influences of sex and initial landing posture on the biomechanical determinants of EA. The landing biomechanics of 80 subjects were recorded during drop landings in Preferred, Flexed, and Erect conditions. No sex differences in joint EA were identified after controlling for initial landing posture. Males and females exhibited greater ankle EA during Erect vs Flexed landings with this increase driven by 12% greater ankle velocity, but no change in ankle extensor moment. No differences in hip and knee EA were observed between conditions. However, to achieve similar knee EA, subjects used 7% greater mean knee extensor moment but 9% less knee angular velocity during Flexed landings. The results suggest that sex‐specific EA strategies do not exist, and that the magnitude of knee joint EA can be maintained by modulating the relative contributions of joint moment and angular velocity to EA.
Neuromuscular response differences to power vs strength back squat exercise in elite athletes
Authors: Brandon R. , Howatson G. , Strachan F. , Hunter A. M.
Published: July 2014

The study's aim was to establish the neuromuscular responses in elite athletes during and following maximal ‘explosive’ regular back squat exercise at heavy, moderate, and light loads. Ten elite track and field athletes completed 10 sets of five maximal squat repetitions on three separate days. Knee extension maximal isometric voluntary contraction (MIVC), rate of force development (RFD) and evoked peak twitch force (Pt) assessments were made pre‐ and post‐session. Surface electromyography [root mean square (RMS)] and mechanical measurements were recorded during repetitions. The heavy session resulted in the greatest repetition impulse in comparison to moderate and light sessions (P < 0.001), while the latter showed highest repetition power (P < 0.001). MIVC, RFD, and Pt were significantly reduced post‐session (P < 0.01), with greatest reduction observed after the heavy, followed by the moderate and light sessions accordingly. Power significantly reduced during the heavy session only (P < 0.001), and greater increases in RMS occurred during heavy session (P < 0.001), followed by moderate, with no change during light session. In conclusion, this study has shown in elite athletes that the moderate load is optimal for providing a neuromuscular stimulus but with limited fatigue. This type of intervention could be potentially used in the development of both strength and power in elite athletic populations.
Virtual Empathy? Anxieties and Connections Teaching and Learning Pastoral Care Online
Authors: McGarrah Sharp Melinda , Morris Mary Ann
Published: July 2014

Is it possible to teach pastoral care online? McGarrah Sharp and Morris describe their process of transforming a residential on‐campus pastoral care course into the first online offering of the course at their seminary. They begin by describing a series of pedagogical choices made with the intent of facilitating dynamic movement between peer‐to‐peer, small group, and whole class discussions throughout the semester. Before and during the course, anxieties arose at many levels of instruction for the professor, teaching assistant, and students. Anecdotes and examples from the online course show how the online course design and facilitation was able to name and respond to anxieties as part of integrating pastoral care course content and practice – a key learning goal for the course. The authors are persuaded that online pedagogy can help identify how anxieties create space for developing empathy as much, if not more than, a traditional on‐campus format.
Forum: A New Culture of Learning
Authors: Hess Mary E. , Gallagher Eugene V. , Turpin Katherine
Published: July 2014

These brief essays byMaryHess,EugeneGallagher, andKatherine Turpin are solicited responses from three different contexts to the provocative book byDouglasThomas andJohnSeelyBrown,The New Culture of Learning(2011).MaryHess writes from a seminary context, providing a critical summary of the authors' major concepts and their ramifications, positive and negative, for theological education and the church.EugeneGallagher writes from a liberal arts setting, identifying characteristics of the face‐to‐face classroom that would go missing in a careless adoption of online learning environments. Finally,Katherine Turpin reports from the classroom, chronicling her experience in a course she redesigned for a graduate theological setting to employ some of the authors' pedagogical principles and strategies. Together, these responses offer critical appreciation and constructive critique of the workThomas andSeelyBrown have done – and point the conversation forward.
Disseminated Bacillus Calmette‐Guérin (BCG) infection following allogeneic hematopoietic stem cell transplant in a patient with Bare Lymphocyte Syndrome type II
Authors: Abu‐Arja R.F. , Gonzalez B.E. , Jacobs M.R. , Cabral L. , Egler R. , Auletta J. , Arnold J. , Cooke K.R.
Published: July 2014

We describe the first case, to our knowledge, of disseminated Mycobacterium bovis Bacillus Calmette‐Guérin infection in a child with Bare Lymphocyte Syndrome type II after undergoing hematopoietic stem cell transplantation (HSCT). The patient presented 30 days post HSCT with fever and lymphadenitis. Lymph node, blood, and gastric aspirates were positive for M. bovis. The patient received a prolonged treatment course with a combination of isoniazid, levofloxacin, and ethambutol. Her course was further complicated by granulomatous lymphadenitis and otitis media associated with M. bovis that developed during immune suppression taper and immune reconstitution. Ultimately, the patient recovered fully, in association with restoration of immune function, and has completed 12 months of therapy.
Prescription patterns and treatment outcomes of MDR‐TB patients treated within and outside the National Tuberculosis Programme in Pham Ngoc Thach hospital, Viet Nam
Authors: Hoa Nguyen B. , Khanh Pham H. , Chinh Nguyen V. , Hennig Cornelia M.
Published: July 2014

Objective

To describe and analyse the prescription patterns and treatment outcomes of MDR‐TB patients managed within Green Light Committee (GLC) and outside (non‐GLC) the National TB programme in Viet Nam.

Methods

Retrospective cohort study with two elements: (i) in‐depth interviews and focus group discussions with clinical doctors, hospital pharmacists, and the non‐GLC patients with MDR‐TB; (ii) review of treatment cards and patients' charts of all GLC and non‐GLC patients with MDR‐TB put on treatment during 2010.

Results

Of 282 patients with MDR‐TB, comprising 79 (28%) GLC patients MDR‐TB and 203 (72%) non‐GLC patients with MDR‐TB, were enrolled in the study. Treatment delay was significantly higher in the GLC group (12.8 days) than the non‐GLC group (2.3 days), (P = 0.004). The success rate was significantly better in GLC patients (84.8%) than in non‐GLC patients (53.7%) (P < 0.001). The default rate was significantly higher in non‐GLC patients than in GLC patients (25.6% vs. 6.3%), (P < 0.001). The risk of unsuccessful outcome was higher in non‐GLC patients (Hazard ratio = 4.6, 95% CI: 1.8–11.8).

Conclusions

The treatment outcomes of patients with MDR‐TB in the GLC group were significantly better than in the non‐GLC group. Reasons for the high default rate in non‐GLC patients with MDR‐TB must be further investigated.
Selection of suitable reference genes for normalization of genes of interest in canine soft tissue sarcomas using quantitative real‐time polymerase chain reaction
Authors: Zornhagen K. W. , Kristensen A. T. , Hansen A. E. , Oxboel J. , Kjær A.
Published: July 2014

Quantitative real‐time reverse transcription polymerase chain reaction (RT‐qPCR) is a sensitive technique for quantifying gene expression. Stably expressed reference genes are necessary for normalization of RT‐qPCR data. Only a few articles have been published on reference genes in canine tumours. The objective of this study was to demonstrate how to identify suitable reference genes for normalization of genes of interest in canine soft tissue sarcomas using RT‐qPCR. Primer pairs for 17 potential reference genes were designed and tested in archival tumour biopsies from six dogs. The geNorm algorithm was used to analyse the most suitable reference genes. Eight potential reference genes were excluded from this final analysis because of their dissociation curves. β‐Glucuronidase (GUSB) and proteasome subunit, beta type, 6 (PSMB6) were most stably expressed with an M value of 0.154 and a CV of 0.053 describing their average stability. We suggest that choice of reference genes should be based on specific testing in every new experimental set‐up.
Offshore Small Modular Reactor (OSMR): An Innovative Plant Design for Societally Acceptable and Economically Attractive Nuclear Energy in a Post-Fukushima, Post-9/11 World
Authors: Buongiorno Jacopo , Golay Michael , Todreas Neil , Briccetti Angelo , Jurewicz Jake , Kindfuller Vincent , Fadel Daniel , Srinivasan Ganesh , Hannink Ryan , Crowle Alan , Corradini Michael
Published: July 2014

The potential for major gains in safety, physical protection and economics of nuclear energy exists through the development of a floating Offshore Small Modular Reactor (OSMR). This is a plant that can be entirely built (and decommissioned) as a floating rig in a shipyard, floated to the operating site (within 8–15 km of the coast), anchored in relatively deep water (i.e., ∼100 m), and connected to the grid via an underwater transmission line. The OSMR design presented here features innovative passive and indefinite emergency core and containment cooling systems that eliminate the loss of ultimate heat sink accident, thus decreasing the likelihood of severe accidents. Furthermore, the OSMR containment design and back-up venting procedures effectively eliminate the threat of serious land contamination, should a severe accident actually occur.
Soil Structure and Fluid Interaction Assessment of New Modular Reactor: Part 2 — Numerical Study of Soil Reactor Structure Interaction
Authors: Ghosh Amitava , Das Kaushik , Basu Debashis , Miller Larry
Published: July 2014

To meet the growing demand of affordable power, several designs of Small Modular Reactors (SMRs), which will be installed below-grade, have been proposed by the nuclear industry. The containment vessels of these reactors will be under water. During a seismic event, these reactors will experience a complex soil (ground)-structure (SMR)-fluid (water) interaction that can affect the integrity of the system. Each of these reactors uses a seismic damping or isolation system to protect its important to safety structures, systems, and components from a design-basis earthquake. Designers of these damping/isolation systems need to have a thorough understanding of the complex soil-structure-fluid interactions to ensure the adequacy of the isolation system. In addition, regulators need to understand these interactions to evaluate the safety of such installations and systems.

This study was initiated to understand the complexities in modeling facility responses that may accompany a design-basis earthquake. The ability to model these complexities is important to designers and regulators. It was recognized that a three-way coupled approach that can satisfactorily model the unique dynamic characteristics of soil surrounding the reactor, the reactor structure, and fluid contained within the reactor is not available. As a first step in understanding the complex interaction phenomena, a sequential coupling approach was adopted in this study. It was assumed that the feedback loop (such as structural deformation affecting ground motion and sloshing) has limited influence because of the high inertia of the massive structure. The general-purpose geological continuum package FLAC was used to simulate the propagation of earthquake-generated ground motion. The fluid analysis was conducted using the commercial computational fluid dynamics (CFD) package ANSYS-FLUENT. This paper briefly discusses the modeling techniques used in soil-structure and structure-fluid interaction analyses. Using a strong motion earthquake record, the ground acceleration at the base of the SMR was calculated and used as input to the CFD analysis of fluid motion inside the structure.
Soil Structure and Fluid Interaction Assessment of New Modular Reactor: Part 1 — Numerical Simulation of Fluid Motion due to Seismic Waves
Authors: Das Kaushik , Ghosh Amitava , Basu Debashis , Miller Larry
Published: July 2014

In recent years, the nuclear industry has proposed design of affordable small modular reactors (SMR), which will be installed below grade. A complex soil-structure-fluid interaction is expected to occur during a seismic event at such installation sites. A thorough understanding of this interaction is needed for the purpose of designing damping or isolation systems as well as to determine the adequacy and safety of these devices. A fully dynamically coupled analysis of the surrounding soil, reactor structure, and contained fluid within the reactor would provide the most accurate estimate of the forces acting on the SMR, but such an exercise is difficult to accomplish due to large discrepancies in length and time scales of each subsystem. It also would be computationally intensive to explicitly model all the detail physical features that affect system response in a single analysis framework. A sequential one-way explicit coupling between parts of the system, such as soil-structure or fluid-structure interaction in response to seismic ground motion, would provide some reasonable engineering information useful to designers and regulators. A two part study was conducted to understand the soil-structure and fluid-structure interaction in response to a seismic event for an SMR. The present paper describes the latter (fluid-structure interaction), where the containment fluid behavior during a seismic event is studied.

A simplified two-dimensional computational fluid dynamics (CFD) model, representing a mockup structure based on the mPower reactor is developed in the study. It is used to simulate the sloshing motion of the fluid during a seismic event. A general volume of flow (VOF) approach is employed to simulate the sloshing motion and track the air-water interface. Ground acceleration calculated from a separate mechanical analysis is adopted in the study to specify the body forces experienced by the fluid. CFD simulations are performed for two different cases that correspond to two different input seismic waveforms. Simulated results highlight the movement of air-water interface due to sloshing within the containment building. The total horizontal and vertical forces on the structure, resulting from the sloshing motion were calculated. A Fourier analysis of the calculated fluid forces shows the dominant frequencies of the force, due to fluid sloshing, are different from that of the seismic acceleration. Similar dominant frequencies of the forces are predicted using two different input seismic waveforms. The magnitudes of the forces varied, depending on the magnitude of the seismic waveform input.
The U.S. Federal Market as an Early Adopter of SMRs
Authors: Barattino William J. , Foster Scott , Spaulding James
Published: July 2014

The Federal Government accounts for about 2% of energy usage within the United States, with electricity accounting for approximately one-fifth of this usage. The Department of Defense (DOD) is the largest energy consumer across all Federal Agencies, accounting for nearly half of total use and has implemented programs to assure sustainable energy supplies for meeting mission critical operations. As prototype systems of Small Modular Reactors mature during the remainder of this decade, there is growing interest at senior levels of government to use the secure confines of military bases for electricity generated with SMRs to service power requirements of the DOD base and possibly the surrounding communities. This paper explores the potential for using DOD as an early adopter of SMRs from perspectives of the size of the market and adaptability of the current procurement process for private ownership of SMRs on military bases. Such an approach is shown to be consistent with DOD Sustainability objectives, as well as ensuring a continuation of the projected erosion of diversity mix for prime power generation within the U.S. A review of contract types for energy services are evaluated from the perspective of including SMRs. Required modifications for SMRs to be a part of this energy mix for Federal Agencies are presented.
Design and Development of EM2
Authors: Schleicher Robert W. , Bertch Timothy
Published: July 2014

The principal design objectives for EM2 are to achieve an economically competitive power source that improves resource utilization, reduces waste and meets a self-imposed high standard of safety. In order to meet this challenge, EM2 departs from traditional nuclear technologies and embraces technical advances in materials, physics design, power conversion, control and passive safety methods. EM2 is a modular helium-cooled fast reactor with a 265MWe net output. It uses a combined Brayton-Rankine cycle to achieve a net conversion efficiency of 53%. The core design is predicated on the convert-and-burn principle in which fertile material is converted to fissile and burned in situ. This allows the core to achieve a 30 year life without refueling or reshuffling. The combination of high efficiency and convert-and-burn reduces the rate of once-through high-level waste production by 80% relative to an LWR. This principle also enables the core to be multi-fuel capable including LEU, natural and depleted U, Th and spent LWR fuel. The base fuel is in the form of UC pellets with SiC composite cladding. These materials allow a high power density and a core outlet temperature of 850°C for high efficiency. The core outlet helium goes directly to a variable speed turbo-compressor within the primary coolant system. The direct Brayton cycle eliminates costly steam generators and large, steam-condensate system components. The bottoming cycle is a self-contained Organic Rankine cycle (ORC). General Atomics (GA) has a bench-scale fuel fabrication facility for making both EM2 fuel pellets and cladding. GA cladding materials have been irradiated in ORNL’s HFIR to demonstrate the desired irradiation saturation behavior. The design is highly modularized not only reduce cost but also the risks associated with construction cost and schedule.
Integrating Safety, Operations, Security, and Safeguards Into the Design of Small Modular Reactors
Authors: Middleton Bobby D. , Mendez Carmen
Published: July 2014

The existing regulatory structure for nuclear power plants impacts both the design and the operation of the facility [1]. The current structure has been known to be overly conservative in several instances. This overly conservative approach results in operational costs to the facility that decrease the profit margin for nuclear power companies. The current design and build process also results in expensive retrofitting and contributes excess costs to the operations of the facility [1]. The current fleet of nuclear reactors is composed mainly of large light water reactors (LWRs) that can, to some extent, counteract these operational costs by the sheer volume of energy produced. However, the deliberately small size of small modular reactors (SMRs) prevents them from benefitting from this economy of scale. In order to be built and operated economically, SMR vendors must find ways to bring the life cycle costs in line with the economic requirements of nuclear power companies.

Sandia National Laboratories has developed a framework that allows vendors and operators to address many of the operational costs during the design and manufacture stages of the SMR life cycle. The framework allows certain operational costs to be addressed in the design stages, thereby decreasing the operational costs, especially those costs associated with staffing and retrofitting. The framework pulls together best practices that have been applied successfully in other industries.

Concurrent Engineering (CE) frames the procedural stages, from defining the expectations of the facility deployment, through the identification of regulatory requirements, to the pre-conceptual, conceptual and detailed design stages. A Project Management Organization is critical to the time management and success of implementing CE. The use of Integrated Safety, Operations, Security, and Safeguards (ISOSS) will lead to achieve a more efficient, cost-effective, and reliable plant. The Balance Model is introduced as a tool to document conflicts between functional areas and identify balancing strategies for conflict resolution in the requirements. Life-Cycle Cost Analysis (LCCA) is proposed as a variable for decision making. Facility Lifecycle Management with Building Information Modeling (BIM) is encouraged to support the Build, Activation, Continued Operations and Decommissioning of the facility [1].

To ensure that the deployment of SMR is effective and cost efficient, the ideal time to implement the framework is now, before SMR designs reach the detailed stage. SMRs hold a lot of potential and this framework can help the nuclear industry realize that potential.
Licensing Process Development for SMRs — European Perspective
Authors: Söderholm Kristiina , Amaba Ben , Lestinen Ville
Published: July 2014

Recently, Small Modular Reactors (SMRs) have attracted increased public discussion. While large nuclear power plant new build projects are facing challenges, the focus of attention is turning to small modular reactors. This paper is based on the PhD Dissertation “Licensing Model Development for Small Modular Reactors (SMRs) - Focusing on Finnsh Regulatory Framework”, approved in 2013.

The result of the study is a recommendation for a new, optimized licensing process for SMRs. The most important SMR-specific feature, in terms of licensing, is the modularity of the design. Here the modularity indicates multi-module SMR designs, which creates new challenges in the licensing process.

The application of the new licensing process is developed using Systems Engineering, Requirements Management, and Project Management practices and tools.
Developing of Safety Analysis and Monitoring Methods Applying to Small Modular Reactors
Authors: Bakhmetyev Alexander M. , Bylov Igor A. , Morev Alexander V. , Baklanov Alexey V.
Published: July 2014

Probabilistic methods allow to evaluate nuclear plant safety level systemically during plant lifetime and to develop recommendations on foreground directions in improving technical measures and operational procedures. Probabilistic assessment of plant safety level requires developing and introduction of appropriate methods and software. During last years JSC “Afrikantov OKBM” has developed different methods and software allowing to perform probabilistic study of nuclear plants safety and has implemented substantial amount of safety analysis and safety monitoring studies for different purposed small modular reactors.

The paper describes methods and software developed by JSC “Afrikantov OKBM” and some results of its utilizing for small modular reactors.
Small Modular Reactor Thermal Performance Improvement With Addition of a High Temperature Gas Reactor Superheater
Authors: Marotta Paul J. , Antar Basil N.
Published: July 2014

Reheating steam from a Small Modular Reactor (SMR) is explored in order to increase efficiency and power output. A thermal source in the form of a High Temperature Gas Reactor (HTGR) is considered. Engineering challenges include proof-of-principle, reactor sizing, evaluation, and feasibility. The proposed thermodynamic process modifications have been evaluated for a range of inlet steam quality conditions. The evaluation of the steam tube dimensions and number of optimal tubes have been calculated utilizing the so-called Log Mean Temperature Difference method. Subsequently, the performance of the steam tubes was further analyzed within a RELAP5 model to investigate two phase boiling flow thermal phenomena. Detailed calculations include a non-uniform axial heat flux distribution based on published results for the tri-structural isotropic fuel system (TRISO). Non-uniform axial heat flux served as the non-uniform heat source boundary condition in the computer model for the High Temperature Gas Reactor. The work shows that the proposed modifications are not only feasible but also show significant improvement for power output in the amount of over 50%, and increase of the power cycle efficiency of over 14%.
Integration of NuScale SMR With Desalination Technologies
Authors: Ingersoll D. T. , Houghton Z. J. , Bromm R. , Desportes C.
Published: July 2014

Nuclear energy plants are attractive energy source for large scale water desalination since the thermal energy produced in a nuclear reactor can provide both electricity and steam to desalt water without the production of greenhouse gases. A particularly attractive option is to couple a desalination plant with the new generation of nuclear plant designs: small modular reactors (SMR). This allows regions with smaller electrical grids and limited infrastructure to add new electrical and water capacity in more appropriate increments and allows countries to consider siting plants at a broader range of distributed locations. The NuScale SMR plant design is especially well suited for the co-generation of electricity and desalted water. The enhanced safety, improved affordability, and deployment flexibilities of the NuScale design provide a cost-effective approach to expanding global desalination capacity. Parametric studies have been performed to evaluate technical options for coupling a NuScale plant to a variety of different desalination technologies. An economic comparison of these options was performed for each of the different desalination technologies coupled to an appropriately sized NuScale plant capable of providing sufficient carbon-free electricity and clean water to support a city of 300,000 people.
Development of a Supervisory Control System Concept for Advanced Small Modular Reactors
Authors: Cetiner Sacit M. , Fugate David L. , Kisner Roger A. , Muhlheim Michael D. , Wood Richard T.
Published: July 2014

Small modular reactors (SMRs) can provide the United States with a safe, sustainable, and carbon-neutral energy source. Because of their small size and, in many cases, simplified nuclear island configurations, it is expected that capital costs will be less for SMRs compared to that of large, Generation III+ light-water reactors. Advanced SMRs (AdvSMRs), which use coolants other than water as the primary heat transport medium, introduce several passive safety concepts and controls features that further reduce the complexity of primary system designs by eliminating redundant components and systems.

Under U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), the Supervisory Control of Multi-Modular SMR Plants project was established to enable innovative control strategies and methods to supervise multi-unit plants, accommodate shared systems, identify opportunities to increase the level of automation, define economic metrics based on the relationship between control and staffing levels, and permit flexible co-generation operational regimes.

This paper documents current findings from the Supervisory Control project. Specifically, it defines and documents strategies, functional elements, and an architectural structure for supervisory control of a representative generic AdvSMR plant. More specifically, this research advances the state-of-the art by incorporating decision making into the supervisory control system architectural layers through the introduction of tiered taxonomy of plant systems and subsystems.

The proposed architecture has the features of planning and scheduling, analyzing plant status, diagnosing problems as they develop and predicting potential future problems, making decisions based on these features, and generating validated commands to lower control layers in the architecture.
Characterization of the cleaning process on a transferred graphene
Authors: Huang Li-Wei , Chang Cheng-Kai , Chien Fan-Ching , Chen Kuei-Hsien , Chen Peilin , Chen Fu-Rong , Chang Chia-Seng
Published: July 2014

Intrinsic graphene possesses many outstanding physical and chemical properties, but their full explorations are often hindered by the effects of substrate and/or contamination. The authors employ the ultrahigh vacuum transmission electron microscopy equipped with a residual gas analyzer to in-situ characterize an effective decontamination process on a suspended graphene. Raman spectroscopic spectra further verify the cleanness of the resultant graphene membrane. The authors also present two contrasting growth morphologies of copper nanoparticles obtained on both clean and unclean graphene surfaces and show that the intrinsic growth dynamics can only manifest on the surface without contaminations.
Surface oxidation of GaN(0001): Nitrogen plasma-assisted cleaning for ultrahigh vacuum applications
Authors: Gangopadhyay Subhashis , Schmidt Thomas , Kruse Carsten , Figge Stephan , Hommel Detlef , Falta Jens
Published: July 2014

The cleaning of metal-organic vapor-phase epitaxial GaN(0001) template layers grown on sapphire has been investigated. Different procedures, performed under ultrahigh vacuum conditions, including degassing and exposure to active nitrogen from a radio frequency nitrogen plasma source have been compared. For this purpose, x-ray photoelectron spectroscopy, reflection high-energy electron diffraction, and scanning tunneling microscopy have been employed in order to assess chemical as well as structural and morphological surface properties. Initial degassing at 600 °C under ultrahigh vacuum conditions only partially eliminates the surface contaminants. In contrast to plasma assisted nitrogen cleaning at temperatures as low as 300 °C, active-nitrogen exposure at temperatures as high as 700 °C removes the majority of oxide species from the surface. However, extended high-temperature active-nitrogen cleaning leads to severe surface roughening. Optimum results regarding both the removal of surface oxides as well as the surface structural and morphological quality have been achieved for a combination of initial low-temperature plasma-assisted cleaning, followed by a rapid nitrogen plasma-assisted cleaning at high temperature.
Stellar activity masquerading as planets in the habitable zone of the M dwarf Gliese 581
Authors: Robertson Paul , Mahadevan Suvrath , Endl Michael , Roy Arpita
Published: July 2014

Tricky star plays sleight-of-light

Two signatures in starlight thought to be written by extrasolar planets may turn out to be forgeries. Astronomers often attribute periodic shifts in a star's apparent motion toward and away from us to the tug of orbiting planets. Robertson
et al.
studied archival spectra of the star Gliese 581 to assess another potential cause: magnetic activity on the star's surface. The signals once attributed to two planet candidates instead resulted from the combined effect of starspots and stellar rotation. Planet hunters be warned—correct for stellar activity in your data analyses.

Science
, this issue p.
440
Genome Sequence of
Streptomyces wadayamensis
Strain A23, an Endophytic Actinobacterium from
Citrus reticulata
Authors: de Oliveira Luciana G. , Tormet Gonzalez Gabriela D. , Samborsky Markyian , Marcon Joelma , Araujo Welington L. , de Azevedo João Lucio
Published: July 2014

The actinobacterium
Streptomyces wadayamensis
A23 is an endophyte of
Citrus reticulata
that produces the antimycin and mannopeptimycin antibiotics, among others. The strain has the capability to inhibit
Xylella fastidiosa
growth. The draft genome of
S. wadayamensis
A23 has ~7.0 Mb and 6,006 protein-coding sequences, with a 73.5% G+C content.
Draft Genome Sequence of Strain Q-1, an Iodide-Oxidizing Alphaproteobacterium Isolated from Natural Gas Brine Water
Authors: Ehara Ayaka , Suzuki Haruo , Kanesaki Yu , Yoshikawa Hirofumi , Amachi Seigo
Published: July 2014

Here we report the draft genome sequence of strain Q-1, an iodide (I
−
)-oxidizing heterotrophic bacterium in the class
Alphaproteobacteria
isolated from natural gas brine water. The genome sequence contained a multicopper oxidase gene probably responsible for iodide oxidation. A photosynthetic gene cluster was found but genes for carbon-fixation were absent.
Draft Genome Sequence of the Rifamycin Producer Amycolatopsis rifamycinica DSM 46095
Authors: Saxena Anjali , Kumari Rashmi , Mukherjee Udita , Singh Priya , Lal Rup
Published: July 2014

Amycolatopsis rifamycinica
DSM 46095 is an actinobacterium that produces rifamycin SV, an antibiotic used against
Mycobacterium tuberculosis
. Here, we present the draft genome of DSM 46095, which harbors a novel rifamycin polyketide biosynthetic gene cluster (
rif
PKS) that differed by 10% in nucleotide sequence from the already reported
rif
PKS cluster of
Amycolatopsis mediterranei
S699.
Complete Genome Sequences of Bacillus subtilis subsp.
subtilis
Laboratory Strains JH642 (AG174) and AG1839
Authors: Smith Janet L. , Goldberg Jonathan M. , Grossman Alan D.
Published: July 2014

The Gram-positive bacterium
Bacillus subtilis
is widely used for studies of cellular and molecular processes. We announce the complete genomic sequences of strain AG174, our stock of the commonly used strain JH642, and strain AG1839, a derivative that contains a mutation in the replication initiation gene
dnaB
and a linked Tn
917
.
Genome Sequence of Klebsiella pneumoniae Urinary Tract Isolate Top52
Authors: Johnson Jeremiah G. , Spurbeck Rachel R. , Sandhu Sukhinder K. , Matson Jyl S.
Published: July 2014

Klebsiella pneumoniae
is a significant cause of nosocomial infections, including ventilator-associated pneumonias and catheter-associated urinary tract infections.
K. pneumoniae
strain TOP52 #1721 (Top52) was isolated from a woman presenting with acute cystitis and subsequently characterized using various murine models of infection. Here we present the genome sequence of
K. pneumoniae
Top52.
Myocardial infarction complicated by left ventricular thrombus and fatal thromboembolism following abrupt cessation of dabigatran
Authors: Weiler Bethany , Marciniak Ellen T , Reed Robert M , McCurdy Michael T
Published: July 2014

Novel anticoagulants are increasingly utilised in lieu of warfarin to treat non-valvular atrial fibrillation. Their clinical use in other non-FDA approved settings is also increasing. We present a case in which a patient abruptly stopped taking dabigatran due to a small bowel obstruction and shortly thereafter suffered a myocardial infarction complicated by left ventricular thrombosis with fatal embolisation to the superior mesenteric artery. In this context, we discuss the possibility of a rebound phenomenon of hypercoagulability with abrupt cessation of novel anticoagulants.
Juvenile myoclonic epilepsy with multiple sclerosis: Is there a dual role for valproate?
Authors: Sharma Chandramohan , Parekh Jigar , Kumawat Bansi Lal , Acharya Mihir
Published: July 2014

A 27-year-old woman was diagnosed with juvenile myoclonic epilepsy since the age of 13 and was on valproate therapy. She had a single episode of demyelinating illness while on valproate therapy. Two years earlier, her medication was changed to lamotrigine to avoid the teratogenic effects of valproate, after which the frequency of her demyelinating events increased to four episodes in 1.5 years, satisfying the revised McDonald criteria for multiple sclerosis. Valproate has been shown to restore T-cell homoestasis and ameliorate pathogenesis of experimental allergic encephalomyelitis, a mouse model of multiple sclerosis. Therefore, we propose a potential dual role of valproate in patients with co-existent juvenile myoclonic epilepsy and multiple sclerosis.
Closing the cleft over a throbbing heart: neonatal sternal cleft
Authors: J Ashok Raja , G Mathevan , K Mathiarasan , P Ramasubramaniam
Published: July 2014

Sternal cleft is a rare anomaly comprising 0.5% of chest wall malformations. We present a case of a neonate with a ‘V’-shaped upper partial sternal cleft at birth. A hyperpigmented cutaneous nevi was present over the cleft. Primary approximation and closure of the defect was performed at 1 week of life. We discuss the presentation and management, and review the literature.