bluuebunny/crossref_metadata_2025 huggingface dataset:
Traumatic dental injuries in Turkish children, Istanbul
Authors: Toprak Mehmet E. , Tuna Elif B. , Seymen Figen , Gençay Koray
Published: February 2014

Aim

Some of the commonly encountered dental emergencies are traumatic dental injuries. The aim of this study was to evaluate traumatic dental injuries with regard to age, gender, etiology, classification of trauma, teeth involved, place of injury, and treatment received by patients who were referred over a 2‐year period to the Istanbul University, Faculty of Dentistry, Clinics of Pedodontics, Istanbul, Turkey.

Materials and Methods

The study was based on the clinical data of 154 patients (337 traumatized teeth). The children were examined clinically for dental injuries by the same investigator. The following information was recorded: age, gender, etiology, localization, place, number of injured teeth, type of trauma, type of tooth, time elapsed between injury and treatment, and treatment provided. Traumatized teeth were assessed according to the classification of the World Health Organization slightly modified.

Results

A total of 154 patients aged 1–13 years presented a total of 337 traumatized teeth (255 permanent and 82 primary). 94 boys (61%) and 60 girls (39%) with a mean age of 7.91 ± 3.15 years participated in the study. Dental injuries were frequent in the 6–12 year age group. The most common type of dental injuries recorded was luxation injuries (43.3%), uncomplicated crown fractures (20.5%), and complicated crown fractures (19.4%). The main causes were falls (55.2%) and being struck by an object (22.1%). The most frequent treatment was examination only (31.8%).

Conclusions

In childhood, a correct diagnosis may affect the management methods and prevent the occurrence of complications after treatment for traumatic dental injuries. Therefore, continuing education programs offering the latest updates in the management of traumatized teeth should be provided for dental and medical practitioners.
Expression of Small Integrin‐Binding LIgand N‐linked Glycoproteins (SIBLINGs) in the reparative dentin of rat molars
Authors: Xie Xiaohua , Ma Su , Li Changcheng , Liu Peihong , Wang Haixia , Chen Li , Qin Chunlin
Published: February 2014

Aim

To analyze the expression and distribution of Small Integrin‐Binding LIgand N‐linked Glycoproteins (SIBLINGs) in reparative dentin (RepD).

Methodology

Cavities on the mesial surfaces of rat molars were prepared to expose the pulp, and a calcium hydroxide agent was applied to cap the exposed pulp. The molars with pulp capping were extracted at postoperative 1, 2, and 4 weeks. The immunolocalization of four SIBLINGs, dentin matrix protein 1 (DMP1), dentin sialoprotein (DSP), bone sialoprotein (BSP), and osteopontin (OPN) in RepD, was analyzed in comparison with reactionary dentin (ReaD) and primary dentin (PD).

Results

At two weeks after operation, the region of the exposed pulp formed a layer of reparative dentin bridge sealing the communication between the cavity and pulp chamber. Dentinal tubules in RepD were more irregular in shape and fewer in number than PD. At postoperative 2 and 4 weeks, RepD had lower levels of DMP1 and DSP than PD. BSP and OPN were present in RepD, but not in PD. RepD showed certain similarities to ReaD in the expression of SIBLINGs.

Conclusions

The reduced levels of DMP1 and DSP may be associated with the decreased number of dentinal tubules in RepD. The expression of BSP and OPN in RepD indicates that the odontoblast‐like cells were attempting to produce a hard tissue at a very rapid pace. These findings suggest that in response to the surgical injury, the newly differentiated odontoblast‐like cells altered their synthesis of the dentinogenesis‐related proteins and produced a hard tissue that is an intermediate between dentin and bone.
Propolis decreases lipopolysaccharide‐induced inflammatory mediators in pulp cells and osteoclasts
Authors: Neiva Kathleen G. , Catalfamo Dana L. , Holliday L. Shannon , Wallet Shannon M. , Pileggi Roberta
Published: February 2014

Background

Intracanal medicaments are used to disinfect the root canal system, reduce interappointment pain and inflammation, and prevent resorption. Bacterial components such as lipopolysaccharide (LPS) are implicated in the development of pulpal and periapical inflammation and inducing osteoclastogenesis. Propolis is a natural, non‐toxic substance collected from bee's wax that has been used for many years in folk medicine. Propolis has been demonstrated to have antibacterial and anti‐inflammatory properties. Our previous studies have shown that propolis inhibits osteoclast maturation. However, the effect of propolis on the inflammatory response of pulp cells and osteoclasts has not been explored.

Aim

The purpose of this study was to evaluate whether propolis alters the inflammatory response of three endodontically relevant cell lines: mouse odontoblast‐like cells (MDPC‐23), macrophages (RAW264.7), and osteoclasts.

Material and methods

Cells were exposed to 0–20 ug ml−1 LPS to induce an inflammatory response, in the presence of propolis or vehicle control. Culture supernatants were collected after 6 and 24 h, and expression of multiple soluble mediators was determined using Luminex® multiplex technology.

Results

Propolis was effective in reducing secretion of the LPS‐induced inflammatory cyto/chemokines: IL‐1α, IL‐6, IL‐12(p70), IL‐15, G‐CSF, TNF‐α, MIP‐1α, MCP‐1, and IP‐10.

Conclusion

Our results demonstrate that propolis suppresses the LPS‐induced inflammatory response of key cells within the root canal system.
Quantitative analysis of neuronal response properties in primary and higher‐order auditory cortical fields of awake house mice (Mus musculus)
Authors: Joachimsthaler Bettina , Uhlmann Michaela , Miller Frank , Ehret Günter , Kurt Simone
Published: February 2014

Because of its great genetic potential, the mouse (Mus musculus) has become a popular model species for studies on hearing and sound processing along the auditory pathways. Here, we present the first comparative study on the representation of neuronal response parameters to tones in primary and higher‐order auditory cortical fields of awake mice. We quantified 12 neuronal properties of tone processing in order to estimate similarities and differences of function between the fields, and to discuss how far auditory cortex (AC) function in the mouse is comparable to that in awake monkeys and cats. Extracellular recordings were made from 1400 small clusters of neurons from cortical layers III/IV in the primary fields AI (primary auditory field) and AAF (anterior auditory field), and the higher‐order fields AII (second auditory field) and DP (dorsoposterior field). Field specificity was shown with regard to spontaneous activity, correlation between spontaneous and evoked activity, tone response latency, sharpness of frequency tuning, temporal response patterns (occurrence of phasic responses, phasic‐tonic responses, tonic responses, and off‐responses), and degree of variation between the characteristic frequency (CF) and the best frequency (BF) (CF–BF relationship). Field similarities were noted as significant correlations between CFs and BFs, V‐shaped frequency tuning curves, similar minimum response thresholds and non‐monotonic rate‐level functions in approximately two‐thirds of the neurons. Comparative and quantitative analyses showed that the measured response characteristics were, to various degrees, susceptible to influences of anesthetics. Therefore, studies of neuronal responses in the awake AC are important in order to establish adequate relationships between neuronal data and auditory perception and acoustic response behavior.
Phylogenetic approaches for studying diversification
Authors: Morlon Hélène
Published: February 2014

Estimating rates of speciation and extinction, and understanding how and why they vary over evolutionary time, geographical space and species groups, is a key to understanding how ecological and evolutionary processes generate biological diversity. Such inferences will increasingly benefit from phylogenetic approaches given the ever‐accelerating rates of genetic sequencing. In the last few years, models designed to understand diversification from phylogenetic data have advanced significantly. Here, I review these approaches and what they have revealed about diversification in the natural world. I focus on key distinctions between different models, and I clarify the conclusions that can be drawn from each model. I identify promising areas for future research. A major challenge ahead is to develop models that more explicitly take into account ecology, in particular the interaction of species with each other and with their environment. This will not only improve our understanding of diversification; it will also present a new perspective to the use of phylogenies in community ecology, the science of interaction networks and conservation biology, and might shift the current focus in ecology on equilibrium biodiversity theories to non‐equilibrium theories recognising the crucial role of history.
A single parameter to evaluate stress state in rail head for rolling contact fatigue analysis
Authors: Pun C. L. , Kan Q. , Mutton P. J. , Kang G. , Yan W.
Published: February 2014

Based on the Smith‐Watson‐Topper (SWT) method, a phenomenological approach for multiaxial fatigue analysis, the maximum SWT parameter is proposed as a single parameter to evaluate the stress state in the rail head for assessing the fatigue integrity of the structure. A numerical procedure to calculate the maximum SWT parameter from a finite element analysis is presented and applied in a case study, where the stress and strain fields due to wheel/rail rolling contact are obtained from a three‐dimensional finite element simulation with the steady‐state transport analysis technique. The capability of the SWT method to predict fatigue crack initiation in the rail head is confirmed in the case study. Analogous to von Mises stress for strength analysis, the maximum SWT parameter can be applied to evaluate the fatigue loading state not only in rail head due to rolling contact fatigue but also in a generic structure subjected to a cyclic loading.
Mechanical and Dielectric Properties of Mullite Fiber‐Reinforced Mullite Matrix Composites with Single Layer CVD SiC Interphases
Authors: Wang Yi , Cheng Haifeng , Wang Jun
Published: February 2014

Mullite fiber‐reinforced mullite matrix (Muf/Mu) composites were fabricated via the solgel process. Prior to the solgel process, SiC coatings were deposited on the fibers by the chemical vapor deposition (CVD) process. Effects of the SiC coatings on the mechanical and dielectric properties of the composites were investigated. The results show that the composites with SiC interphases exhibit evident toughened fracture behavior, and their flexural strength is about 2.37 times that of the as‐received composites. Besides, the complex permittivity of the composites with SiC interphases at X‐band is also increased remarkably due to the existence of carbon in the SiC interphases.
Respiratory syncytial virus‐ and human metapneumovirus‐associated emergency department and hospital burden in adults
Authors: Widmer Kyle , Griffin Marie R. , Zhu Yuwei , Williams John V. , Talbot H. Keipp
Published: February 2014

Objective

Determine the burden of illness associated with respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) in adults, especially young adults.

Design

Prospective surveillance study using RT‐PCR for the diagnosis of RSV and HMPV.

Setting

One academic Emergency Department (ED), one academic hospital and three middle Tennessee community hospitals.

Sample

We prospectively enrolled Middle Tennessee residents ≥18 years old evaluated in the emergency department (ED) or hospitalized for respiratory symptoms May 2009 through April 2010. We collected nose/throat specimens for RSV and HMPV reverse‐transcriptase polymerase chain reaction (RT‐PCR) testing and obtained demographic and clinical data.

Main outcome Measures

Rates of ED visits and hospitalizations were calculated using the proportion of enrolled patients positive for each virus multiplied by the number of Middle Tennessee residents evaluated in EDs and/or hospitalized in Tennessee for acute respiratory illness during the study period.

Results

Three thousand two hundred and fifty six patients were eligible; 1477 (45·4%) were enrolled; 1248 (84·5%) of these consented to additional testing and had adequate samples. RT‐PCR identified 32 (2·6%) patients with RSV and 33 (2·6%) with HMPV. The median duration of symptoms before ED presentation was 3·3 days with RSV and 2·8 days with HMPV, and before hospital admission was 4·5 days with RSV and 3·5 days with HMPV. The annual hospitalization and ED visit rates were similar for RSV and HMPV. The hospitalization rate associated with each virus was about 10 per 10 000 persons aged ≥50 years; ED rates were approximately 2 times higher. Hospitalization rates were about 2 per 10 000 persons aged 18–49 years, with ED rates 5–6 times higher.

Conclusion

RSV and MPV are associated with substantial disease in adults, with hospitalization and ED visits rates increasing with age.
Competitive Advantage and the Existence of the Multinational Corporation: Earlier Research and the Role of Frictions
Authors: Asmussen Christian Geisler , Foss Nicolai J.
Published: February 2014

This article provides a counterpoint to Hashai and Buckley's article ‘Is competitive advantage a necessary condition for the emergence of the multinational enterprise?’ We agree with their conclusion that it is, in fact, not a necessary condition, but argue that the theoretical reasons behind this are different and more diverse than the ones they propose. We suggest that much extant economic theory is, in fact, consistent with their view that firms may internationalize without owning or achieving competitive advantages, and we model various other ways in which imperfections can drive their overall result. We strongly applaud Hashai and Buckley's attempt to add more rigor to international business theory and call for future work to extend this debate.
The Outsourcing Strategy of Local and Multinational Firms: A Supply Base Perspective
Authors: Mol Michael J. , Brewster Chris
Published: February 2014

Firms outsource through connecting to local and global supply bases and making such connections produces costs of search and evaluation, which are a function of transaction characteristics and firm capabilities. We argue that firms outsource more when those costs are low. Hence, domestic subsidiaries of multinational firms, with low cost access to both local and global supply bases, outsource more than either domestic firms or foreign subsidiaries, as confirmed by evidence from a large data panel. We also propose that among foreign subsidiaries, distance from the home country co‐determines search and evaluation costs such that subsidiaries from more distant countries outsource less. This is confirmed for geographic distance, but a positive effect is found for political distance and a mixed effect for cultural distance.
Local Context and Global Strategy: Extending the Integration Responsiveness Framework to Subsidiary Strategy
Authors: Meyer Klaus E. , Estrin Saul
Published: February 2014

The integration‐responsiveness (IR) framework is a leading analytical tool of global strategy but it is less valuable in explaining the heterogeneity of strategic choice for subsidiaries within an MNE. We propose an IRE framework of subsidiary strategy that complements the IR framework for the subsidiary level with a third dimension—selling to local versus export markets (E). Resource‐based considerations suggest that subsidiary strategies must fit the resources both the parent MNE and the local context. We examine how our three dimensions of subsidiary strategy are locally contingent. We suggest that local resource endowments, local competition, and the distance between the home and host country influence the use of responsiveness and exporting strategies, but influence integration strategies only to a small degree. We find empirical support for hypotheses developed from these arguments using survey data from MNE subsidiaries in two Central and Eastern European economies.
Institutional Advantage
Authors: Martin Xavier
Published: February 2014

Is there such a thing as institutional advantage—and what does it mean for the study of corporate competitive advantage? In this article, I develop the concept of institutional competitive advantage, as distinct from plain competitive advantage and from comparative institutional advantage. I first identify and synthesize insights from strategy and institutional theories. I then arrive at a definition of institutional advantage and develop theory about its predictors, emphasizing a firm's interaction with institutions over its life cycle. This analysis highlights foreign direct investment and multinational enterprise as prime venues for insights into institutional advantage from a strategic perspective.
Morphology and Molecular Phylogeny of a New Haptorian Ciliate, Chaenea mirabilis sp. n., with Implications for the Evolution of the Dorsal Brush in Haptorians (Ciliophora, Litostomatea)
Authors: Kwon Choon Bong , Vďačný Peter , Shazib Shahed Uddin Ahmed , Shin Mann Kyoon
Published: February 2014

We discovered a new haptorian ciliate, Chaenea mirabilis sp. n., in brackish water collected near the town of Busan, Korea. Its morphology was studied using standard taxonomical methods and its phylogenetic relationships were assessed by phylogenetic analysis of the 18S rRNA gene. Chaenea mirabilis is distinguished from all congeners by the combination of the following traits: (i) a narrowly bursiform to flask‐shaped, 60–100 μm long body; (ii) 11–21 doughnut‐shaped or sometimes horseshoe‐shaped macronuclear nodules; (iii) two types of extrusomes: type I is rod‐shaped and 6–8 μm long, while type II is narrowly to broadly teardrop‐shaped and only 1.5–2 μm long; (iv) highly refractive special granules tightly arranged between the first and second brush row, forming a conspicuous bulge; and (v) 12–13 somatic kineties. In the 18S rRNA gene phylogeny, C. mirabilis clustered with full support with other congeners. However, there was no statistical support for classification of Chaenea into the families Fuscheriidae, Acropisthiidae, or Trachelophyllidae, but a sister relationship with the Lacrymariidae could not be excluded. Therefore, we establish a new family, Chaeneidae, within the order Lacrymariida. This affiliation is strongly corroborated by the distinctly subapical dorsal brush bearing cilium‐like bristles.
Primordial germ cells in the dorsal mesentery of the chicken embryo demonstrate left–right asymmetry and polarized distribution of the EMA1 epitope
Authors: Hen Gideon , Friedman‐Einat Miriam , Sela‐Donenfeld Dalit
Published: February 2014

Despite the importance of the chicken as a model system, our understanding of the development of chicken primordial germ cells (PGCs) is far from complete. Here we characterized the morphology of PGCs at different developmental stages, their migration pattern in the dorsal mesentery of the chicken embryo, and the distribution of the EMA1 epitope on PGCs. The spatial distribution of PGCs during their migration was characterized by immunofluorescence on whole‐mounted chicken embryos and on paraffin sections, using EMA1 and chicken vasa homolog antibodies. While in the germinal crescent PGCs were rounded and only 25% of them were labeled by EMA1, often seen as a concentrated cluster on the cell surface, following extravasation and migration in the dorsal mesentery PGCs acquired an elongated morphology, and 90% exhibited EMA1 epitope, which was concentrated at the tip of the pseudopodia, at the contact sites between neighboring PGCs. Examination of PGC migration in the dorsal mesentery of Hamburger and Hamilton stage 20–22 embryos demonstrated a left–right asymmetry, as migration of cells toward the genital ridges was usually restricted to the right, rather than the left, side of the mesentery. Moreover, an examination of another group of cells that migrate through the dorsal mesentery, the enteric neural crest cells, revealed a similar preference for the right side of the mesentery, suggesting that the migratory pathway of PGCs is dictated by the mesentery itself. Our findings provide new insights into the migration pathway of PGCs in the dorsal mesentery, and suggest a link between EMA1, PGC migration and cell–cell interactions. These findings may contribute to a better understanding of the mechanism underlying migration of PGCs in avians.
The reproducibility of temporomandibular joint vibrations over time in the human
Authors: Zhang J. , Whittle T. , Wang L. , Murray G. M.
Published: February 2014

The aim of the study was to assess the reproducibility of vibrations recorded from the temporomandibular joint (TMJ) in a group of healthy subjects. The vibrations from TMJ were recorded bilaterally from 34 healthy subjects by electrovibratography in three sessions at intervals of 3 min and again after 1 week. The total integral of the vibration energy, the ratio of the integral between frequencies above 300 Hz and below 300 Hz (ratio of >300 Hz/<300 Hz), peak frequency, median frequency, peak amplitude and distance to centric occlusion position were calculated. Data were analysed with intraclass correlation coefficients (ICC) and two‐way anova for repeated measures. All variables showed good to excellent reliability across different sessions (ICCday1: 0·935–0·987; ICCday2: 0·910–0·992) and across different days (ICC: 0·738–0·907). According to anova for repeated measures, all variables showed good reproducibility (P > 0·05) between sessions at the same day. There was no significant difference between the 2 days for the frequency‐related variables including peak frequency (P = 0·083), median frequency (P = 0·188) and ratio of >300 Hz/<300 Hz (P = 0·26). There was a statistical difference between the 2 days for the intensity‐related vibration variables including total integral (P = 0·045) and peak amplitude (P = 0·026). The wave patterns of the power‐frequency spectra were qualitatively similar over both the sessions and days. Joint vibration analysis could provide a fast, non‐invasive, and repeatable method to record the status of TMJ. Further studies are needed to identify the characteristic waveforms for different subgroups of temporomandibular disorders and to evaluate the possibility of diagnostic value.
Protective effects of farnesoid X receptor (FXR) on hepatic lipid accumulation are mediated by hepatic FXR and independent of intestinal FGF15 signal
Authors: Schmitt Johannes , Kong Bo , Stieger Bruno , Tschopp Oliver , Schultze Simon M. , Rau Monika , Weber Achim , Müllhaupt Beat , Guo Grace L. , Geier Andreas
Published: February 2014

Background & Aims

There is a growing evidence that bile acids are involved in the regulation of triglyceride‐, cholesterol‐homoeostasis and fat absorption. In this study organ‐specific Fxr knockout mice were used to further investigate the influence of farnesoid X receptor FXR in lipogenesis.

Methods

Liver‐ and intestine‐specific Fxr knockout mice were fed a 1% cholesterol diet for 28 days. Histological examination of frozen tissue sections included Sudan III/H&E, BODIPY staining and liver X receptor (LXR) immunohistochemistry. Liver triglycerides, serum cholesterol, serum bile acids and nuclear LXR protein were measured. mRNA expression of several genes involved in bile acid‐, cholesterol‐homoeostasis and lipogenesis was quantified by real‐time PCR.

Results

Hepatic FXR deficiency contributes to lipid accumulation under 1% cholesterol administration which is not observed in intestinal Fxr knockout mice. Strong lipid accumulation, characterized by larger vacuoles could be observed in hepatic Fxr knockout sections, while intestinal Fxr knockout mice show no histological difference to controls. In addition, these mice have the ability to maintain normal serum cholesterol and bile acid levels. Hepatic Fxr knockouts were characterized by elevated triglycerides and bile acid levels. Expression level of LXR was significantly elevated under control and 1% cholesterol diet in hepatic Fxr knockout mice and was followed by concomitant lipogenic target gene induction such as Fas and Scd‐1. This protective FXR effect against hepatic lipid accumulation was independent of intestinal Fgf15 induction.

Conclusion

These results show that the principal site of protective bile acid signalling against lipid accumulation is located in the liver since the absence of hepatic but not intestinal FXR contributes to lipid accumulation under cholesterol diet.
Quand la famille se déchire: analyse des sections divergentes cantonales lors des votations populaires 2003‐2011
Authors: Cappelletti Fabio , Dacorogna Basile
Published: February 2014

L'apparition de sections cantonales divergentes lors des votations populaires est un phénomène récurrent en Suisse. Toutefois, malgré l'intérêt de son analyse pour apprécier la cohésion interne des partis, ce phénomène a été délaissé par la littérature récente. Nous comblons ce manque par une analyse à la fois quantitative et qualitative des sections divergentes lors des votations populaires des deux dernières législatures (2003‐2007 et 2007‐2011). L'analyse quantitative illustre une stabilité, voire une légère diminution, du phénomène. L'analyse qualitative (études de cas) quant à elle, relativise son impact sur la cohésion des partis: ses manifestations les plus importantes sont circonscrites à des domaines spécifiques et sont provoquées par des configurations particulières, ou des causes spécifiques.
Biochar amendment to coarse sandy subsoil improves root growth and increases water retention
Authors: Bruun E. W. , Petersen C. T. , Hansen E. , Holm J. K. , Hauggaard‐Nielsen H.
Published: February 2014

Crop yields and yield potentials on Danish coarse sandy soils are strongly limited due to restricted root growth and poor water and nutrient retention. We investigated if biochar amendment to subsoil can improve root development in barley and significantly increase soil water retention. Spring barley (Hordeum vulgare cv. Anakin) was grown in soil columns (diameter: 30 cm) prepared with 25 cm topsoil, 75 cm biochar‐amended subsoil, and 30 cm un‐amended subsoil lowermost placed on an impervious surface. Low‐temperature gasification straw‐biochar (at 0, 0.50, 1.0, 2.0, and 4.0 wt%) and slow pyrolysis hardwood‐biochar (at 2 wt%) were investigated. One wt% can be scaled up to 102 Mg/ha of char. After full irrigation and drainage, the in‐situ moisture content at 30‐80 cm depth increased linearly (R2 = 0.99) with straw‐biochar content at a rate corresponding to 0.029 m3/m3/%. The lab determined wilting point also increased linearly with char content (R2 = 0.99) but at a much lower rate (0.003 m3/m3/%). Biochar at concentrations up to 2% significantly increased the density of roots in the 40–80 cm depth interval. Addition of 1% straw‐biochar had the most positive effect on root penetration resulting in the highest average root density (54% coverage compared to 33% without biochar). This treatment also resulted in the greatest spring barley grain yield increase (22%). Improving the quality of sandy subsoils has global potentials, and incorporation of the right amount of correctly treated residues from bioenergy technologies such as straw‐biochar is a promising option.
Nature of Palaeozoic extension in Lofoten, north Norwegian Continental Shelf: insights from 3‐D seismic analysis of a Cordilleran‐style metamorphic core complex
Authors: Henstra Gijs Allard , Rotevatn Atle
Published: February 2014

Analyses of 3‐D seismic data reveal that pre‐Triassic basins are present underneath the Mesozoic North Træna Basin (Lofoten Margin, Norway). These are linked to a Cordilleran‐style metamorphic core complex that developed in Palaeozoic times, including rotated fault blocks with hanging wall ‘growth’ wedges, bounded by listric faults that sole into a sub‐horizontal detachment. On the basis of similarity in age, structural style and transport direction, we propose a kinematic link with a Permian mylonitic detachment documented onshore. This study presents the first offshore evidence for Palaeozoic detachment faulting, elucidating the mechanisms behind the long‐lived exhumation history of the Lofoten basement.
Reaction phenotyping of vinblastine metabolism in dogs
Authors: Achanta S. , Maxwell L. K.
Published: February 2014

Vinblastine is a vinca alkaloid used either as a single agent or in combination therapy for the treatment of canine mast cell tumours and lymphomas. The objective of this study was to determine which isoform of cytochrome P450 enzyme is responsible for the majority of vinblastine metabolism in dogs. A panel of eight recombinant canine cytochrome P450 enzymes (CYP1A1, CYP1A2, CYP3A12, CYP3A26, CYP2B11, CYP2C41, CYP2C21 and CYP2D15) were incubated in vitro with vinblastine. Findings were confirmed by the use of canine polyclonal antibodies of cytochrome P450 enzymes (CYP1A1, CYP3A12, CYP2B11 and CYP2C21) that were pre‐incubated with individual and pooled hepatic microsomes that were purified from canine liver. Substrate depletion was observed in the presence of recombinant CYP3A12, whereas depletion did not substantially occur when microsomes were pre‐incubated with polyclonal antibodies against CYP3A12. These findings confirmed that CYP3A12 is the major cytochrome P450 isoform responsible for the metabolism of vinblastine in dogs.
Coupled Neutronics/Thermal-Hydraulics for Analysis of Molten Salt Reactor
Authors: Guo Zhangpeng , Xiao Yao , Zhou Jianjun , Zhang Dalin , Chaudri Khurrum Saleem , Qiu Suizheng
Published: February 2014

The Generation IV international Forum (GIF) selected molten salt reactor (MSR) among six advanced reactor types. It is characterized by a liquid circulating fuel that also serves as coolant. In this study, a multiple-channel analysis code (MAC) is developed and it is coupled with MCNP4c to analyze the neutronics/thermal-hydraulics behavior of Molten Salt Reactor Experiment (MSRE). The MAC calculates thermal-hydraulic parameters, such as temperature distribution, flow distribution and pressure drop. MCNP4c performs the analysis of effective multiplication factor, neutron flux and power distribution. A linkage code is developed to exchange data between MAC and MCNP to implement coupling iteration process until the power convergence is achieved. The coupling calculation can achieve converged solution after a few iterations. The results are in reasonable agreement with the analytic solutions from the ORNL. This work was helpful for further design analysis and operation of MSR.
The Study of Panic to Nuclear Energy on Psychological and Sociological Issues
Authors: Shen Kehan , Fang Chao , Lei Changzhou , Wang Xiaoye
Published: February 2014

Nuclear safety attracts many concerns from society especially after Fukushima accident. In recent years, although nuclear safety system has been continuously improved on the aspects of design functions, safety standards and safety assessment methods, etc., the public panic has not been reduced correspondingly. In some countries and regions, the public nuclear panic has a strong impact on the sustainable development of nuclear energy, which has been widely recognized by nuclear industries worldwide. In this paper, we studied the nuclear public panic from three aspects with the analysis of psychological and sociological methods, including: (1) Discussing the source of nuclear panic in the sense of Maslow’s hierarchy of needs and psychoanalysis; (2) Systemically studying the irrational behaviors in nuclear accidents and the public nuclear culture with cognitive theory; (3) Giving out the general model of public nuclear panic. In the last, some suggestions of nuclear risk perception and communication were also shown as reference, which are significant for the future work.
The Design and CFD Simulation of a New Spent Fuel Pool Passive Cooling System
Authors: Ye Cheng , Wang Minglu , Zheng Mingguang , Xiong Zhengqin , Zhang Ronghua
Published: February 2014

Due to the safety issues arising from the Fukushima accident, a novel completely passive spent fuel pool cooling system is proposed using the high-efficiency heat pipe cooling technology that is available in an emergency condition such as a station blackout. This cooling system’s ability to remove the decay heat released by the spent fuel assemblies is evaluated by a computational fluid dynamics (CFD) simulation. The spent fuel pool of CAP1400 (a passive PWR developed in China) is selected as the reference pool, and the passive cooling system is designed for this spent fuel pool. The pool with the passive cooling system is simulated using Fluent 13.0 with 4 million meshes. Four different cases have been studied, and some notable results have been obtained through this work. The simulation results reveal that the passive cooling system effectively removes the decay heat from the SFP with the storage of 15-year-old spent fuel assemblies with emergency reactor core unloading and prevents the burnout of the fuel rods. The results indicate that the water in the SFP will never boil, even in a severe accident with a lack of emergency power and outside aid.
Numerical Analysis of the Residual Heat Removal for the Spent Fuel Storage Tank of HTR-10
Authors: Wang Jinhua , Wang Bing , Wu Bin , Lui Jiguo
Published: February 2014

Chinese 10 MW High Temperature Gas Cooled Reactor (HTR-10) has inherent safety; the residual heat of the spent fuel could be removed by natural ventilation in loading process. The spent fuel storage tank could shield radiation; the outside is covered by an iron sleeve; the spent fuel tank would be stored in atmosphere after fully loaded, and the residual heat could be discharged by natural ventilation in interim storage stage. The calculation showed that, the maximum temperature locates in the middle of the fuel pebble bed in the spent fuel tank in loading process and interim storage stage, and the temperature decrease gradually with radial distance; the temperature in the tank body and sleeve is evenly; it is feasible to remove the residual heat of the spent fuel tank by natural ventilation, and in the natural ventilation condition, the temperature of the spent fuel and the tank is lower than the temperature limit, which provides theoretical evidence for the choice of the residual heat removal method in loading process and interim storage stage.
Research and Development of 3D Module Design System in Nuclear Power Engineering
Authors: Lu Qinwu , Li Yi , Wang Zengchen , Luo Yalin
Published: February 2014

In order to meet the requirement of independent research and development of modular technology in nuclear power project, a set of convenient and efficient 3D module design system is supplied to the designer with the support of CPR1000 and on the basis of module 3D design system researched and developed by PDMS 3D cooperative design platform. The function and applying effect of 3D module design system can be referred to the research of the second function of PDMS 3D cooperative design platform.
On the Applicability of Pool Boiling Models in TRACE for the Evaluation of a Counter-Current LBE-Water Heat Exchanger
Authors: Jaeger Wadim , Sánchez Espinoza Victor Hugo
Published: February 2014

A counter current LBE-Water heat exchanger is investigated with the system code TRACE with emphasize on the water side. Due to the liquid metal coolant on the outer side of the heat exchanger the present boundary conditions for the water side (pressure, mass flux, heat flux, etc.) might be out of range of normal LWR application and need therefore additional validation. The review of the physical models of TRACE, mainly the ones for pool boiling, indicated that these models might not be applicable to the present heat exchanger design. Alternative pool boiling models have been implemented into TRACE, namely the ones of Forster-Zuber and of Labuntsov. The comparison shows that the heat transfer coefficient of the original model is about 30% higher than with the alternative models but with a wall heat flux which is almost identical for the three models. This is caused by the much lower heat transfer coefficient on the LBE side which dictates the global heat transfer. The resulting wall temperature and the power which can be transferred from the hot LBE side to the water are lower for the alternative models. That indicates that with the standard model too optimistic results might be calculated.
A Proposal on Ultimate Safety Disposal of High Level Radioactive Wastes
Authors: Yoshikawa Hidekazu
Published: February 2014

The ultimate disposal of high-level radioactive waste (HLW) becomes a hard issue for sustainable nuclear energy in Japan especially after Fukushima Daiichi accident. In this paper, the difficulty of realizing underground HLW disposal in Japanese islands is first discussed from socio-political aspects. Then, revival of old idea of deep seabed disposal of HLW in Pacific Ocean is proposed as an alternative way of HLW disposal. Although this had been abandoned in the past for the reason that it will violate London Convention which prohibits dumping radioactive wastes in public sea, the author will stress the merit of seabed disposal of HLW deep in Pacific Ocean not only from the view point of more safe and ultimate way of disposing HLWs (both vitrified and spent fuel) than by underground disposal, but also the emergence of new marine project by synergetic collaboration of rare-earth resource exploration from the deep sea floor in Pacific Ocean.
Preliminary Analysis of Two-Phase Flow in a Steam Generator Using CUPID-SG
Authors: Kim Hyungrae , Kim Soo Hyoung , Lee Seung-Jun , Park Ik Kyu , Yoon Han Young
Published: February 2014

CUPID-SG is a component scale thermal-hydraulic analysis tool based on CUPID, which is intended to be a computer code for analyzing two-phase flows in porous media with tube bundles such as PWR steam generators. CUPID-SG adopts two-fluid, three-field conservation equations, and uses an in-house semi-implicit solver to obtain numerical efficiency. CUPID-SG can handle unstructured meshes that enable its application in complex geometries. CUPID-SG also has constitutive models for a two-phase flow map, interfacial heat and mass transfer, interfacial drag, wall friction, wall heating, and heat partitioning. CUPID-SG is benchmarked against a few cases of FRIGG tests to confirm that the transport models are correctly implemented and the code is applicable to a two-phase flow over tube bundles. The comparison showed that the constitutive models are properly implemented and CUPID-SG is capable of analyzing a two-phase boiling flow over tube bundles.
The Application of AFAL Methodology in Substantiation of Instrument Calibration Intervals Extension in Nuclear Power Plant
Authors: Zhou Ping , Xu Xiajun , Tu Caiqing
Published: February 2014

This is an Introduction about the AFAL methodology of study the instrument drift characteristics, and the application of AFAL in substantiation of instrument calibration interval extension in nuclear power plant. AFAL methodology main aspects include collecting historical instrument calibration data of nuclear power plant, calculating statistics values such as: sample number, mean, median, standard deviation, then work out the drift tolerance interval of the instrument. Based on analysis of these statistical calculated values, will understand the instrument drift performance.

This article also discusses technical issues associated with the application of AFAL and how to solve them, such as: grouping instrument, sample sizes, outliers detecting and processing, high-confidence deduction etc. Through the study of the instrument drift characteristics, evaluate the performance of instrument, determine the calibration interval can prolong properly.

The application practices of AFAL methodology show, extending instrument calibration interval can support nuclear power plant to achieve the goal of prolonging the fuel cycle, under the nuclear safety precondition. The nuclear power plant can improve the capacity factor of the unit and economic performance.
Scaling Assessment for the Integral Effect Tests: 1 — Closed Loop Natural Circulation
Authors: Cai Xiaoyu
Published: February 2014

In this paper a method is described for using NOTRUMP models to corroborate the Hierarchical Two-Tiered Scaling (H2TS) methodology that has been used for design of the APEX and SPES-2 test facilities. These facilities were built for the Westinghouse Electric Company to obtain data on the performance of the passive safety systems of the advanced pressurized water reactors.

Similarity between the prototype system and the scaled test facilities is investigated for the closed loop natural circulation phenomena in the postulated small break loss of coolant accident (SBLOCA). The objective of this analysis is to provide a basis that an integral test for the passive safety system will provide valid experimental data for the high-ranked phenomena that may occur during the hypothetical SBLOCA transients. In this way, the experiment will capture the phenomena that would be expected to occur in the plant, and hence provide data that can be used to validate computer code.
Experimental Validation for Specific Thermal Hydraulic Phenomena of SMART
Authors: Chung Young-Jong , Lee Won Jae , Ha Jaejoo
Published: February 2014

SMART (System-integrated Modular Advanced ReacTor) is an integral light water reactor developed by KAERI for both electricity generation and various applications. SMART can produce 90MWe of electricity and 40,000 tons/day of sea-water desalination, which is deemed suitable for a city population of 100,000. The SMART project aims at standard design approval. The experimental validation for SMART specific thermal hydraulic phenomena is to generate background information required for SMART licensing.

The objective of the experimental validation is to demonstrate the safety and performance of the SMART-specific system and component designs, and to provide a database for the validation of the design tools, such as a system analysis code. From the experimental results, it is proved that SMART was designed properly and the data are used to approve the validation of the system analysis code. Also, the experimental results were submitted to a regulatory body as technical background information of the SMART standard design, and they enhance the licensing possibility of this design.
A New Method to Weaken Thermal Stratification Phenomena in Pipes of Nuclear Power Plant
Authors: Wang Shengfei , Pang Yuxin , Li Xiaojing , Fu Dandan , Li Yang , Yin Jiaju
Published: February 2014

Thermal stratification phenomena are observed in piping systems of pressurized water reactors, especially in the pressurizer surge line. As a result of the thermal stratification induced thermal stresses, fatigue problems can occur in the pipework. US NRC requirements have also identified flow stratification in surge lines as a phenomenon that must be considered in the design basis of surge lines. In this paper, a new method to reduce thermal stratification is proposed. As we all know, heat pipe is a simple device with no moving parts and can transfer large quantities of heat over fairly large distance. The new method is that using heat pipes to weaken the thermal stratification. In order to validate the new method, a simple experiment and theoretical analysis was taken. The results show that, the temperature difference of thermal stratification with heat pipes is smaller than the stratification without heat pipes. A design scheme was also given at the end of paper.
Electron and Beta Dose Rates of UO2 Pellet and Fuel Rod
Authors: Zhang Guoqing , Wang Xuexin , Zhang Jiangang , Zhuang Dajie , Li Chaoduan , Gao Fan
Published: February 2014

The isotopes of uranium and their daughter nuclides inside the UO2 pellet emit mono-energetic electrons and beta rays, which generate rather high dose rate near the UO2 pellet and could cause exposure to workers. In this work calculations of electron dose rates have been carried out with Monte Carlo codes, MCNPX and Geant4, for a UO2 pellet and a fuel rod. Comparisons between calculations and measurements have been carried out to verify the calculation results. The results could be used to estimate the dose produced by electrons and beta rays, which could be used to make optimization for radiation protection purpose.
New Cooling Scheme of First Wall in HCCB TBM and Related Performance Analysis
Authors: Wang Qijie , Cao Qixiang , Zhao Zhou , Feng Kaiming
Published: February 2014

In the design and analysis for the ITER TBM, a key issue is the cooling of the First Wall. For safety, the First Wall FW must be designed to withstand the thermal radiation load from the plasma and the nuclear heat generated by nuclear reaction, and it should satisfy related stress criteria. For technology, it also should meet a pressure drop limits and other engineering requirement.

The former cooling scheme design showed some shortcoming in temperature distribution uniformity and pressure drop, in order to improve it, a new cooling scheme has been designed and analyzed.

The paper describes the detail of the new cooling scheme of FW, and a series related analysis was conducted to compare with former design. In the preliminary analysis, the new cooling scheme design showed much advantage to the former design.

The working conditions of the analysis have been set to ITER design condition. The performances and the results obtained thermo-hydraulics and stress, are presented.
A Scaling Analysis of a CANDU-6 Moderator Tank Scaled-Down Test Facility
Authors: Rhee Bo W. , Kim H. T. , Park S. K. , Cha J. E. , Choi H.-L.
Published: February 2014

Several studies have been performed to derive a set of scaling criteria which were thought to be suitable for reproducing thermal-hydraulic phenomena in a scale-down CANDU moderator tank similar to that in a prototype power plant during a full power steady state condition[1,2]. The major variables of interests are moderator flow circulation and temperature inside the moderator tank during a steady state condition. The key phenomena involved include the inlet jet development and impingement, buoyancy force driven by the moderator temperature difference caused by non-uniform heating, and the viscous friction of the flow across the calandria tube array.

In these studies, the governing equations were initially transformed into dimensionless equations based on the representative characteristic values of the basic design such as the time, tank diameter, inlet fluid velocity, and average temperature rise, and 3 dimensionless numbers, Re, Pr, Ar, were identified as those characterizing the key phenomena of the system. The relevant boundary conditions were then identified in a dimensionless form, and the compatibility of keeping these 3 dimensionless numbers, the volumetric heat source distribution, and the boundary conditions in dimensionless forms the same for both the prototype and scale-down tanks were examined, and some of them that are less important are relaxed so as to find a practically implementable set of constraints. The size of the scaled-down moderator tank and corresponding inlet velocity is then found for the available power supply size. As an example, an analysis was performed for a power supply capacity of 500 kW as compared to 100MW for the prototype.

As a way to confirm the validity of the current work two numerical CFD simulations were carried out with the boundary conditions at the inlet and outlet ports, and on the walls of the solid structures, such as the moderator tank and calandria tubes, which were derived from those of the dimensionless scales to check if the moderator flow and temperature patterns of both the prototype reactor and scaled-down facilities are identical or at least similar. A steady-state solution is first obtained for the candu-6 reactor normal operation. Similar simulation was done for the scaled-down facility and results presented. Comparison results are discussed, and the cause of the potential distortion of the scaling owing to practical limitations and possible solutions is finally discussed.