bluuebunny/crossref_metadata_2025 huggingface dataset:
New diagnostic and imaging technologies in dermatology
Authors: Jartarkar Shishira R , Patil Anant , Wollina Uwe , Gold Michael H. , Stege Henner , Grabbe Stephan , Goldust Mohamad
Published: October 2021

Introduction

Diagnosis of dermatological disorders is primarily based on clinical examination in combination with histopathology. However, clinical findings alone may not be sufficient for accurate diagnosis and cutaneous biopsies are being associated with morbidity.

Objective

The objective of this article is to review the newer technologies along with their applications, limitation and future prospectus.

Methodology

Comprehensive literature search was performed using electronic online databases “PubMed” and “Google Scholar”. Articles published in English language were considered for the review.

Results

In order to improve and/or widen the armamentarium in dermatologic disease diagnosis and therapy, newer emerging technologies are being made available which aid in diagnosis and management. New emerging technologies include confocal microscopy, digital photographic imaging, optical coherence tomography, high frequency ultrasonography, and artificial intelligence. There have been advancements in the dermoscopes.

Conclusion

Significant progress is seen in the diagnostic methods and imaging technologies in dermatology, each having its advantages and limitations. Artificial intelligence/machine‐based learning software may have a great scope to influence the dermatological practice.
Relationship between demographic factors, health education, breast cancer‐related knowledge, attitudes, and breast self‐examination behavior among Chinese female college student: A structural equation analysis
Authors: Zhang Shunhua , Zhu Weihao , Chen Baole , Tang Ting , Tao Zhaoyu , Li Xiang , Hua Tiantian , Ju Nianting , Zheng Suge
Published: October 2021

Aims

This study aimed to create a structural equation model to evaluate the associations among demographic factors, health education, breast cancer‐related knowledge, attitudes, and breast self‐examination behavior among Chinese female college students.

Methods

A survey was undertaken using a self‐administered questionnaire and targeting 2233 students from Eastern China. Structural equation modeling with the bootstrap approach was utilized to estimate the interrelationships and the strength of the associations among measured variables based on the hypothetical model.

Results

Among the total participants, 14.7% of the female college students reported having performed breast self‐examination. The final structural equation model showed highly satisfactory fitness on indices. Breast self‐examination behavior was significantly linked to demographic factors, breast cancer related‐knowledge, attitudes, and health education. Health education had the greatest influence on breast self‐examination behavior. In addition, breast cancer related‐knowledge was significantly associated with demographic factors and health education. Health education and knowledge all significantly affected attitudes towards breast cancer.

Conclusion

Breast self‐examination behavior was influenced by demographic factors, breast cancer related‐knowledge, attitudes towards breast cancer, and health education in a sample of female college students in China. Health education was the most important predictor of breast self‐examination behavior.
The Role of Frictions due to Top Management in Alliance Termination Decisions: Insights from Established Bio‐Pharmaceutical Firms
Authors: Ghosh Anindya , Klueter Thomas
Published: October 2021

This study examines the termination of research alliances by established firms accessing knowledge from smaller research partners. We relax the assumption implicit in the internal tension perspective of alliance termination that signals from a partner are readily processed and acted upon. Instead, we consider that large firms involved in the alliance may have distributed decision‐making structures involving both alliance managers in charge of day‐to‐day activities and top managers who are responsible for a company’s strategic decision making. Using the information‐processing view of the firm we theorize on frictions as top managers evaluate the balance of tensions within the alliance. First, signals collected by units involved in the alliance must receive top management attention. Second, the accuracy and reliability with which signals are evaluated and acted upon is contingent on the composition of the top management team. An analysis of 235 alliances initiated by Top 50 pharmaceutical firms broadly supports our theoretical framework.
What do people find most meaningful? How representations of the self and the world provide meaning in life
Authors: Costin Vlad , Vignoles Vivian L.
Published: October 2021

Objective

Recent theories propose that global meaning in life (MIL) is based on feelings of coherence, purpose, and existential mattering. MIL has also been linked to mental representations—for example, beliefs, values, attitudes, and identities—that serve as “meaning frameworks” for interpreting the world and oneself. Combining these proposals, we predicted that beliefs, values, attitudes, and identities would foster a sense of MIL to the extent that they provide feelings of coherence, purpose, and existential mattering.

Method

Using multilevel path analysis, we tested within‐person associations of coherence, purpose, and existential mattering with a sense of MIL across three studies (Study 1:208 US MTurk workers; Study 2:106 UK university students; Study 3:296 from a UK nationally representative Prolific sample). We explored the generality of these associations across mental representation types and individual differences.

Results

Participants derived greater MIL most strongly from mental representations that provided sense of purpose, followed by existential mattering. Sense of coherence was less robustly related to MIL across mental representation types and religious orientation.

Conclusions

Integrating prior theorizing on MIL, we conclude that mental representations function as “meaning frameworks” to the extent that they provide feelings of purpose, mattering, and, sometimes, coherence.
TRAPPC11‐related muscular dystrophy with hypoglycosylation of alpha‐dystroglycan in skeletal muscle and brain
Authors: Munot Pinki , McCrea Nadine , Torelli Silvia , Manzur Adnan , Sewry Caroline , Chambers Darren , Feng Lucy , Ala Pierpaolo , Zaharieva Irina , Ragge Nicola , Roper Helen , Marton Tamas , Cox Phil , Milev Miroslav P. , Liang Wen‐Chen , Maruyama Shinsuke , Nishino Ichizo , Sacher Michael , Phadke Rahul , Muntoni Francesco
Published: October 2021

Aims

TRAPPC11, a subunit of the transport protein particle (TRAPP) complex, is important for complex integrity and anterograde membrane transport from the endoplasmic reticulum (ER) to the ER–Golgi intermediate compartment. Several individuals with TRAPPC11 mutations have been reported with muscle weakness and other features including brain, liver, skeletal and eye involvement. A detailed analysis of brain and muscle pathology will further our understanding of the presentation and aetiology of TRAPPC11 disease.

Methods

We describe five cases of early‐onset TRAPPC11‐related muscular dystrophy with a systematic review of muscle pathology in all five individuals, post‐mortem brain pathology findings in one and membrane trafficking assays in another.

Results

All affected individuals presented in infancy with muscle weakness, motor delay and elevated serum creatine kinase (CK). Additional features included cataracts, liver disease, intellectual disability, cardiomyopathy, movement disorder and structural brain abnormalities. Muscle pathology in all five revealed dystrophic changes, universal hypoglycosylation of alpha‐dystroglycan and variably reduced dystrophin‐associated complex proteins. Membrane trafficking assays showed defective Golgi trafficking in one individual. Neuropathological examination of one individual revealed cerebellar atrophy, granule cell hypoplasia, Purkinje cell (PC) loss, degeneration and dendrite dystrophy, reduced alpha‐dystroglycan (IIH6) expression in PC and dentate neurones and absence of neuronal migration defects.

Conclusions

This report suggests that recessive mutations in TRAPPC11 are linked to muscular dystrophies with hypoglycosylation of alpha‐dystroglycan. The structural cerebellar involvement that we document for the first time resembles the neuropathology reported in N‐linked congenital disorders of glycosylation (CDG) such as PMM2‐CDG, suggesting defects in multiple glycosylation pathways in this condition.
Romosozumab versus Teriparatide for the Treatment of Postmenopausal Osteoporosis: A Systematic Review and Meta‐analysis through a Grade Analysis of Evidence
Authors: Tian Aixian , Jia Haobo , Zhu Shan , Lu Bin , Li Yan , Ma Jianxiong , Ma Xinlong
Published: October 2021

Objective

To provide a systematic review about the efficacy and safety of romosozumab and teriparatide for the treatment of postmenopausal osteoporosis.

Method

Randomized controlled trials (RCTs) were searched from electronic databases, including PubMed (1996 to June 2019), Embase (1980 to June 2019), Cochrane Library (CENTRAL, June 2019), Web of Science (1998 to June 2019), and others. The primary outcomes included the following: the percentage change in bone mineral density of lumbar spine and total hip from baseline at month 6 and month 12 in each group. The secondary outcomes included the following: the percentage change in bone mineral density of femoral neck from baseline at month 6 and month 12 in each group and the incidence of adverse events at month 12 in each group.

Results

Four studies containing 1304 patients met our selection criteria. The result of our analysis indicated that romosozumab showed better effects in improving BMD of lumbar spine (month 6: MD = 3.54, 95% CI [3.13, 3.94], P<0.001; month 12: MD = 4.93, 95% CI [4.21, 5.64], P<0.001), total hip (month 6: MD = 2.27, 95% CI [0.62, 3.91], P = 0.007; month 12: MD = 3.17, 95% CI [2.68, 3.65], P<0.001), and femoral neck (month 6: MD = 2.30, 95% CI [0.51, 4.08], P = 0.01; month 12: MD = 3.04, 95% CI [2.29, 3.78], P<0.001). Also, the injection‐site reaction was less (month 12: RR = 2.84, 95% CI [1.22, 6.59], P = 0.02), but there were no significant difference in the incidence of serious adverse events (month 12: RR = 0.78, 95% CI [0.46, 1.33], P = 0.37) and death (month 12: RR = 0.61, 95% CI [0.08, 4.62], P = 0.63).

Conclusion

Based on the available studies, our current results demonstrate that romosozumab was better than teriparatide both in terms of efficacy and side effects.
Catheter ablation of atrial fibrillation in patients with cor triatriatum sinister; case series and review of literature
Authors: Karimianpour Ahmadreza , Cai Amanda W. , Cuoco Frank A. , Sturdivant John Lacy , Litwin Sheldon E. , Wharton John Marcus
Published: October 2021

Introduction

Cor triatriatum sinister (CTS) is a rare congenital heart defect characterized by fibromuscular septation of the left atrium associated with atrial fibrillation (AF). The incidence of hemodynamically insignificant CTS in the AF ablation population and effect on ablation success are not known. Furthermore, little is known about the potential effect of CTS on arrhythmogenic substrate.

Objective

We define the incidence of hemodynamically insignificant CTS in patients undergoing AF ablation with RF and cryoballoon ablation, the technical challenges created by the left atrial partitioning, and the potentially arrhythmogenic effects of the membrane. We also review the literature of CA in patients with CTS.

Methods

First‐time AF ablation cases at our institution over a 10‐year period were screened to identify patients with CTS. Retrospective review was performed to obtain clinical characteristics and ablation data.

Results

Of the 3953 consecutive patients undergoing initial AF ablation during the study period, four patients (0.10%) had CTS. Ablation was successful acutely in all patients. One patient had recurrent AF and required repeat ablation for a single procedure success rate of 75% and multi‐procedure success rate of 100%. The CTS membrane was associated with low voltage zones in the two patients in whom it was measured and with substrate for macro‐reentrant atrial tachycardia in one of these patients.

Conclusion

The incidence of hemodynamically insignificant CTS in patients undergoing CA for AF is very low, but does not serve as a significant barrier to successful ablation as long as directed access to the superoposterior chamber is obtained.
Oral support for patients with severe motor and intellectual disabilities
Authors: Nakamura Tatsuya , Kita Yosuke , Fujimoto Junpei , Ayuzawa Koichi , Ozawa Hiroshi
Published: October 2021

Background

Oral support during feeding was clinically provided to patients with severe motor and intellectual disabilities (SMID) for the prevention of dysphasia. The present study investigated the advantages of oral support anatomically and functionally.

Methods

A videofluoroscopic swallowing study was conducted on nine patients with SMID (age = 5–41 years; mean age = 15.0; four males, five females) and 24 healthy adults (age = 26–67 years; mean age = 44.3; 16 males, eight females). The movements of the hyoid bone and mandible during pharyngeal swallowing were tracked, and the pharyngeal residues were evaluated. The temporal and spatial features of the movements were compared between patients with and without oral support as well as healthy adults.

Results

The mandible moved downward earlier and showed larger displacement in the patients with SMID. The patients also had insufficient anterior displacement of the hyoid, which was associated with the pharyngeal residue. This displacement was enhanced, and the pharyngeal residue decreased with oral support.

Conclusions

Oral support to hold the mandible successfully improved hyoid excursion and reduced pharyngeal residue during swallowing, which is a simple and reliable strategy for the prevention of dysphasia in patients with SMID.
Gendered experience in student mobility programs—Global Korea Scholarship recipients' evaluation of Korea's country image
Authors: Lee Hyelim , Snow Nancy
Published: October 2021

According to 2012 Organisation for Economic Co‐operation and Development (OECD) statistics, 11 of 19 OECD countries have a higher female international student participation ratio in student mobility. South Korea has a higher ratio of female international students in general and a higher ratio of female Global Korea Scholarship (GKS) recipients. In 2018 and 2019, we surveyed GKS students about their evaluation of South Korea's country image and discovered significant differences by gender. Female students tend to show a lower cognitive and affective evaluation of the GKS country image experience than male students. We aim to uncover the determinants of these asymmetrical gender‐based differences in the perceived country image of South Korea. Two adjustment indicators (emotional well‐being and feeling part of society) and three adjustment factors (language skills, length of stay, and perceived discrimination) were examined to explore the determinants of gendered favorability toward the country. The findings suggest that female and male GKS recipients have different gendered experiences in the country, which, in turn, impacts their evaluation of South Korea's country image. The findings contribute to the country image and public diplomacy studies and practice, particularly in sponsored student mobility programs, which often fail to distinguish gendered experiences in their analysis or program planning.

Related Articles in this Special Issue

Ayhan, Kadir Jun, and Nancy Snow. 2021. “Introduction to the Special Issue—Global Korea Scholarship: Empirical Evaluation of a non‐Western Scholarship Program from a Public Diplomacy Perspective.” Politics & Policy 49(6): 1282–1291. https://doi.org/10.1111/polp.12440.

Istad, Felicia, Eriks Varpahovskis, Ekra Miezan, and Kadir Jun Ayhan. 2021. “Global Korea Scholarship Students: Intention to Stay in the Host Country to Work or Study after Graduation.” Politics & Policy 49(6): 1323–1342. https://doi.org/10.1111/polp.12436.

Tam, Lisa, and Kadir Jun Ayhan. 2021. “Evaluations of People, Affection, and Recommendation for a Host Country: A Study of Global Korea Scholarship (GKS) Recipients.” Politics & Policy 49(6): 1292–1307. https://doi.org/10.1111/polp.12438.
Molecular phylogenetic, morphological, and pathogenic analyses reveal a single clonal population of Septoria lycopersici with a narrower host range in Brazil
Authors: da Costa Christiane A. , Lourenço Valdir , Santiago Michele F. , Veloso Josiene S. , Reis Ailton
Published: October 2021

Septoria leaf spot, caused by Septoria lycopersici, is considered one of the most important diseases of tomato in Brazil. Despite its importance, the disease agent is still poorly studied. Septoria isolates collected from different production regions of Brazil were characterized by molecular, morphological, and pathogenic methods. A set of 104 isolates was sequenced for the DNA Tub, Cal, and EF1‐α loci. Ten isolates were selected, according to geographical region of origin and type of leaf lesion (typical or atypical), for morphological characterization and for evaluation of aggressiveness on tomato cultivar Santa Clara. To evaluate the pathogen host range, cultivated and wild Solanaceae plants were inoculated with four selected isolates. The results showed that all isolates grouped with the type isolate of S. lycopersici in maximum likelihood and Bayesian inference trees. The isolates were morphologically similar. All isolates selected for pathogenicity testing on tomato were able to induce typical symptoms of the disease, but differed in their aggressiveness. A total of eight species of Solanaceae were also identified as potential alternative hosts for S. lycopersici. This information will provide a more accurate assessment of the risks involved with the introduction of new crops, especially of the genus Solanum, in areas where the species is already present. In addition, it will provide the basis for the establishment of more efficient methods in the management of Septoria leaf spot of tomatoes in natural conditions and in the different production systems.
The spectrum of kidney dysfunction requiring chronic dialysis therapy: Implications for clinical practice and future clinical trials
Authors: Murea Mariana , Deira Javier , Kalantar‐Zadeh Kamyar , Casino Francesco G. , Basile Carlo
Published: October 2021

Staging to capture kidney function and pathophysiologic processes according to severity is widely used in chronic kidney disease or acute kidney injury not requiring dialysis. Yet the diagnosis of “end‐stage kidney disease” (ESKD) considers patients as a single homogeneous group, with negligible kidney function, in need of kidney replacement therapy. Herein, we review the evidence behind the heterogeneous nature of ESKD and discuss potential benefits of recasting the terminology used to describe advanced kidney dysfunction from a monolithic entity to a disease with stages of ascending severity. We consider kidney assistance therapy in lieu of kidney replacement therapy to better reconcile all available types of therapy for advanced kidney failure including dietary intervention, kidney transplantation, and dialysis therapy at varied schedules. The lexicon “kidney dysfunction requiring dialysis” (KDRD) with stages of ascending severity based on levels of residual kidney function (RKF)—that is, renal urea clearance—and manifestations related to uremia, fluid status, and other abnormalities is discussed. Subtyping KDRD by levels of RKF could advance dialysis therapy as a form of kidney assistance therapy adjusted based on RKF and clinical symptoms. We focus on intermittent hemodialysis and underscore the need to personalize dialysis treatments and improve characterization of patients included in clinical trials.
Sulking behavior and the emergence of hurt feelings in young children
Authors: Hardecker David J. K. , Schmidt Marco F. H. , Haun Daniel B. M.
Published: October 2021

When do hurt feelings develop? The emotion of feeling hurt is vital for close relationships because it signals that one has been devalued illegitimately, potentially eliciting guilt and the motivation to repair in the partner. We approached the question of when hurt feelings develop by studying the emergence of sulking behavior as an indicator of hurt feelings. In an online‐questionnaire study, parents and teachers hypothesized that children begin to sulk during the first 3 years (N = 125). In a cross‐sectional event‐based diary study, parents observed their 1‐ to 8‐year‐old children (N = 40). We found that the youngest child sulked at 20 months of age and that the probability of sulking was at 50% for a child at 25 months. Finally, we conducted a longitudinal event‐based diary study where parents observed their children from 16 months on until they sulked for the first time and, at the longest, until their third birthday (N = 29). We found that the probability of sulking was at 25% at 21 months, at 50% for a child at 24–25 months, and at 75% at 28 months, thus, confirming and specifying the results of studies 1 and 2. These findings indicate that the emotion of hurt feelings emerges mainly during the end of the second and the third year. We discuss the limitations of our approach and why and how the development of hurt feelings in the sense of an appraisal needs to be addressed differently.
Locating and categorizing causes of discomfort during transport of patients to medical facilities
Authors: Peulić Aleksandar , Peulić Miodrag , Jovanović Željko , Joković Miloš , Stojković Sanja , Vagić Nemanja
Published: October 2021

This article presents geographic information system usage in transportation management for comfort calculations, analysing vehicle vibration data measured during patient transportation. The main goal of this article is to develop a methodology for automatic discomfort cause recognition (DCR) that may be tested under real life conditions. We analysed differences between uncomfortable locations detected by passengers during patient transportation (according to their subjective opinions) and uncomfortable locations detected by the measurement system. The measuring system is based on the three‐axis accelerometer which is used to determine road comfort values for specific locations gathered by a GPS module. The results obtained were compared with data collected by passengers. During driving, when they experienced discomfort, passengers marked locations in near real time using the GIS. The data thus obtained were analysed with the data obtained by DCR. For the first time, the application of GIS provides analytical tools to create spatial data and define spatial data relations that determine comfort. Testing under real conditions, involving three separate cases, shows a high degree of correlation between the results. The proposed system allows dynamic comfort threshold criteria management and provides a visual representation of summarized tabular data.
Rethinking the geographies of finance for urban climate action
Authors: Robin Enora
Published: October 2021

Research on the geographies of finance for urban climate action has generated important insights into how climate agendas contribute to the financialisation of urban environments and strengthen the position of market actors in urban governance. However, by focusing on a limited set of financial instruments (e.g., green bonds, carbon credits), actors (e.g., real estate developers, private investors, international organisations), and projects (e.g., large‐scale infrastructure), existing studies overlook the heterogeneity of financial relations, initiatives, and actors that make possible urban climate action. This includes, for instance, the deployment of decentralised, small‐scale renewable energy technologies, or community‐led adaptation efforts. In this paper, I explore how theorisations of heterogeneous/hybrid infrastructure, diverse economies, and popular economies can advance current research, through the analysis of three decentralised renewable energy projects in France, the UK, and Zimbabwe. These concepts, I argue, can help us to expand our understanding of the multiple financial relations that underpin urban climate interventions and to explore their implications for the agency of different actors, particularly those who are most affected by climate change impacts.
Workers should take steps to mitigate surface lead exposure when using lead‐containing personal protective equipment
Authors: Mayer Monique N. , Sukut Sally L. , Blakley Barry , Waldner Cheryl L. , Adesina Kayode , Belotta Alexandra F. , Koehncke Niels K.
Published: October 2021

Veterinary workers use lead shielding for protection against harm from ionizing radiation during diagnostic imaging. Surface lead on shielding has been reported as a potential exposure hazard. The purpose of this prospective, analytical, descriptive study was to measure surface lead on lead‐containing shielding in the field service and small animal radiology areas of a veterinary teaching hospital, and to examine potential risk factors for surface lead. Surface lead on a convenience sample of 54 lead shielding items was measured in a commercial laboratory using inductively coupled plasma mass spectrometry. The median and range of surface lead for aprons, thyroid collars, and gloves were 3.6 μg/dm2 (range, 1.3‐22.4 μg/dm2), 23.1 μg/dm2 (range, 2.6‐116 μg/dm2), and 134 μg/dm2 (range, 1.5‐155 μg/dm2), respectively. In the final multivariable analysis, the mean surface lead on thyroid collars and gloves was higher than on aprons (relative differences 4.8, 95% confidence interval [CI] 2.2, 10.5, P < 0.001; and 9.5, 95% CI 4.4, 20.6, P < 0.001, respectively). The mean surface lead on shielding in the worst condition was higher than on shielding in the intermediate and best conditions (P < 0.001). Lead shielding provides effective protection against the harmful effects of ionizing radiation, and shielding should always be worn during radiation exposure. Based on our findings and the common use of lead shielding in veterinary workplaces, we recommend that employers inform workers of this hazard and provide training on steps to mitigate exposure, including the use of disposable gloves when wearing lead shielding and handwashing after use.
Family involvement in transitional care from hospital to home and its impact on older patients, families, and health care providers: a mixed methods systematic review protocol
Authors: Thiengtham Supavadee , D’Avolio Deborah , Leethong-in Mayuree
Published: October 2021

Objective:

The goal of this review is to synthesize the available evidence on family involvement in transitional care and its impact on patients’ and family caregivers’ health as well as health care providers’ satisfaction.

Introduction:

Involving families in transitional care from hospital to home has been undertaken to improve care quality, patient safety, and well-being. Successful family involvement in care depends on the interaction between the health care system and health care providers. However, family involvement in this process has not yet been systematically examined. This review will examine published quantitative and qualitative studies to create a better understanding of family involvement in transitional care.

Inclusion criteria:

This review will consider family involvement in transitional care, encompassing older patients, family caregivers, and health care providers. The quantitative component will compare family involvement interventions with standard care or alternative interventions. Outcomes will be grouped by older patients, family caregivers, and health care providers. For the qualitative component, the subjective experiences of all groups will be explored.

Methods:

Eligible quantitative, qualitative, and mixed method studies will be searched in databases and gray literature sources. The review will consider studies from 1989 to the present, published in English or Thai. Study selection, critical appraisal, data extraction, and data synthesis will be undertaken by two independent reviewers following the segregated JBI approach to mixed methods reviews.

Systematic review registration number:

PROSPERO CRD42020191464
Void Fraction Measurement and Prediction of Two-Phase Boiling Flows in a Tubular Test Section
Authors: Liu Qingqing , Diaz Julio , Petrov Victor , Burak Adam , Manera Annalisa , Kelly Joseph , Sun Xiaodong
Published: October 2021

Void fraction is one of the most important parameters that affect two-phase flow heat transfer and pressure drop. In this paper, a commercial gamma densitometer and a high-speed X-ray radiography system developed at the University of Michigan (UM) are used to measure the void fraction in two-phase boiling flows, with water as the working fluid, in a tubular test section. The test section is made of Incoloy 800H/HT with a total length of 1.589 m, an inner diameter of 12.95 mm, and a wall thickness of 3.05 mm. These two instrumentation systems are installed on a traversing platform that travels along the vertical test section for measurements at multiple elevations. Subcooled flow boiling and natural convection boiling experiments are performed to measure the void fraction in the test section. Flow visualization images are obtained for bubbly and slug flows from the X-ray radiography system. The wall temperature of the test section is measured at 17 elevations by thermocouples. In addition to the experiments, a multiphase computational fluid dynamics (MCFD) model is developed using ANSYS FLUENT to simulate the subcooled flow boiling. The measured wall temperature and void fraction from the experiments are compared with the MCFD simulation results. The RMS (Root mean square) errors are 3.6% and 16.1% for the wall temperature and void fraction, respectively, between the experimental data and MCFD simulations.
Development of Cesium Trap Material for Coated Fuel Particles in High Temperature Gas-Cooled Reactors
Authors: Sasaki K. , Miura S. , Fukumoto K. , Goto M. , Ohashi H.
Published: October 2021

Cs-Bi and Cs-Sb absorbed graphite samples (Cs-Bi/graphite and Cs-Sb/graphite) were synthesized and their high temperature chemical stabilities were tested up to 1500 °C by TG and analyzed by TEM-EDS for the development of Cs trap material in high temperature gas-cooled reactor (HTGR) fuel particles. It was observed that Cs was stabilized by Sb but not by Bi in the specimens after the TG test. A rapid weight loss from 800 to 1000 °C may be caused by evaporation of Cs (boiling point: 671 °C) was seen in the TG result of both specimens. Precipitated Cs-Sb substance in the graphite matrix were not resolved even after the 1500 °C heating. The chemical composition of the Cs-Sb was specified as Cs3Sb. The experimental results suggest that Sb have potential to be a Cs getter material in graphite matrix. Long term heating test should be performed to confirm adaptability of Sb for Cs trap material in HTGR fuel particles.
Oxidation Behaviors of the High Temperature Alloys in the Impure Helium and Argon
Authors: Zheng Wei , Li Haoxiang , Wang Qiuhao , Yin Huaqiang , He Xuedong , Fan Hua , Ma Tao
Published: October 2021

The trace number of impurities such as CO, H2, H2O, and CH4, which existed in the primary coolant of High Temperature Gas-Cooled Reactor (HTGR), has an adverse effect on the structural metallic materials at elevated temperatures. Mainly, it includes oxidation, decarburization, and carburization. The simulative corrosion test was conducted on the four alternative materials of the steam generator in HTGR: Inconel 617, Incoloy 800H, Hastelloy X, and T-22. At 950°C, the alloys were exposed to the helium and argon with impurities for 50 hours. The corroded samples were analyzed by weighing, scanning electron microscope (SEM), and electron probe microanalyzer (EPMA). Inconel 617, Incoloy 800H, and Hastelloy X formed the chromerich scale on the surface. Due to the low oxidizable elements content and low oxygen partial pressure, the continuous scale of T-22 alloy was not observed. Although Inconel 617 and Incoloy 800H formed the thick oxidation layer, pores on the surface may weaken the corrosion resistance. For Inconel 617, the Chromium Depletion occurred near the corrosion layer. In addition, the high temperature alloys showed similar corrosion behaviors in the helium and argon with trace impurities. This proves that the corrosion behavior of superalloys at 950°C will not change after replacing helium with argon, providing an alternative to helium in the corrosion test atmosphere.
Experimental Observation of Nucleate Boiling Entrainment in a Liquid Film
Authors: Tabuchi Junpei , Narushima Yuki , Katono Kenichi , Okawa Tomio
Published: October 2021

Many studies have been conducted on droplet entrainment in an annular flow regime, but little is known about droplet entrainment caused by nucleate boiling. In this report, visualization results of droplet entrainment caused by nucleate boiling are described. We observed two processes of droplet entrainment. The first one causes bubble bursting at a water surface. The second one causes filament breakup which occurs when the vapor bubble reaches and collapses at the interface between air and liquid. From comparison of the phenomena for the two processes, we found that the diameters of the droplets and vapor bubbles were considerably different. Using the results of this research allows the effect of forced convection to be taken into account. In the future, we plan to expand the amount of data and develop a boiling entrainment model under forced convection conditions.
Analysis of Friction Factor of Two-Phase Flow in Helically Coiled Tubes
Authors: Jiang Baihui , Zhou Zhiwei , Ji Yu
Published: October 2021

With compact structure and enhanced heat transfer capacity, helical-coiled once through steam generators (HTSGs) are widely used in the small modular reactors (SMRs). Nevertheless, the inside centrifugal forces make the flow more complicated, and increase the frictional pressure drop, which is closely related to the dual test of alternating thermal stress and flow instability. Therefore, the analysis of the friction factor in helically coiled tubes is significant to the efficient and safe operation of HTSGs.

While the friction factor of single-phase flow in helically coiled tubes was fully studied and extensive correlations have been validated by a large amount of experimental data, the friction factor of two-phase flow still lacks feasible prediction due to its much more complexity. The existed correlations of two-phase flow in helically coiled tubes are mostly based on specified experimental parameters, so the applicable range is limited. Few scholars have tried to extend these correlations to broader applicability, but the trivial applicable range is unsuitable for program development or engineering design, which needs an accurate prediction of friction factor in a wider range.

In this paper, existing frictional pressure drop correlations are investigated. The accuracy of single-phase frictional pressure drop correlations is verified through the comparison of calculation results. Since the known experimental data cannot cover a wide range of parameters, two assumptions are proposed, and the rationality is verified through the existing experimental data and calculation analysis. Based on the two assumptions and calculation, a set of calculation correlations for frictional pressure drop of two-phase flow in helically coiled tubes are proposed. The accuracy of this calculation model is validated by experimental data. The scope of application of this model is: D / d = 15–100, P = 0.12–6.3MPa, G = 200–1500kg / m2s, which is sufficient to support the design and operation of steam generators and the development of the simulation programs.
Sensitivity Analysis on the Blast Resistance of Steel Concrete Structure Wall Based on CONWEP
Authors: Ren Guopeng , Pan Rong , Sun Feng , Li Liang
Published: October 2021

In the modern society, more and more explosive accidents and explosive terror attacks have happened around the world. These explosions not only inflict heavy casualties and property loss, but also cause serious damage to related structures. The outer wall of the nuclear island plant of newly constructed nuclear power unit is usually designed as the steel concrete (SC) structure to prevent from explosion and aircraft impact. This paper selects the steel concrete structure wall composed of surface steel plate, stud, tie bar and concrete as the study object. It adopts classical explicit nonlinear dynamic analysis software ANSYS/LS-DYNA to conduct a series of parameter sensitivity analysis on the impact of blast resistance of the steel concrete structure wall based on the CONWEP method. These parameters include: the explosive scaled distance, thickness of the steel plate, thickness and grade of the concrete, diameter and spacing of tie bars, etc. The analysis results indicate that the above mentioned parameters, especially the explosion scaled distance, the thickness of the wall and the spacing of tie bars, affect the blast resistance capacity of the wall. This paper contributes to the guiding and referencing significance for the design and optimization of the steel concrete structure outer wall of nuclear island plant.
All-Coefficient Adaptive Control System Design for a Space Nuclear Reactor
Authors: Ma Qian , Yu Zhitong , Sun Peiwei , Jia Yuwen , Wu Shifa
Published: October 2021

Topaz-II is a space nuclear reactor developed by the Former Soviet Union. It is a thermal-neutron reactor with UO2 ceramics as fuel. Electricity is generated based on the principle of thermoelectric conversion. The reactivity is controlled by several groups control drums. Its lifetime can be three years and its reactivity feedback and further dynamic characteristics are varying with its lifetime. The positive reactivity feedback characteristics and different dynamic characteristics in different lifetime make it changeling to design a suitable control system for Topaz-II.

All-coefficient adaptive control is a single-input single-output adaptive control method applied to a parameter unknown, linear time invariant or slowly varying object. In some specific conditions, it is also suitable for the non-linear systems. In this method, the model where the sum of coefficients is equal to one is reconstructed based on the original dynamic model. All coefficients in this model can be identified. Therefore, it is possible to realize the optimal control.

Firstly, the model of Topaz-II nuclear reactor system is built. It includes point-reactor kinetics model with six groups delayed neutrons, a one-dimensional lumped transient thermal model of the nuclear fuel element and the moderator, a thermionic model of the converters, a control drum drive model. The reactivity feedbacks with fuel temperature and moderator are considered. Based on the model, the dynamic characteristics are analyzed.

Then, with the nonlinear model of Topaz-II nuclear reactor system, the transfer functions are obtained and analyzed. Based on the transfer functions, the model where the sum of coefficients is equal to one is built by using the all-coefficient adaptive control method. After dealing with the parameter and analyzing the error, the all-coefficient adaptive control systems are designed.

To evaluate the performance of the control systems, power maneuvering events including a 30%FP (Full Power) step change and a reactivity disturbance of 0.0065 are simulated. The responses with traditional and proposed control methods are evaluated and compared. The simulation results show that the all-coefficient adaptive control system has a better performance in settling time and overshoot compared with those with traditional PID controller.
Fragmentation and Cooling Behavior of a Simulated Molten Core Material Discharged Into a Sodium Pool With Limited Depth and Volume
Authors: Matsuba Ken-ichi , Kato Shinya , Kamiyama Kenji , Akayev Assan S. , Baklanov Viktor V.
Published: October 2021

In order to obtain experimental knowledge on fragmentation and cooling behavior of molten core material discharged into regions where the depth and volume of sodium are limited, a series of out-of-pile experiments using alumina (Al2O3) as a simulated molten core material was conducted at an experimental facility of National Nuclear Center of the Republic of Kazakhstan (NNC/RK). In this experimental series, approximately 9 kg of molten alumina was discharged through a duct of 40 mm in inner diameter into a test vessel (200 mm in depth and 300 mm in inner diameter) installed in an outer large vessel filled with sodium. The discharge mass of molten alumina and the dimension of the inner test vessel were determined so that the bulk temperature of sodium inside the test vessel could exceed its saturation temperature. Flow holes were provided in the top lid of the inner test vessel to allow sodium flow between the inner and outer vessels. The shape of solidified alumina recovered from the inner test vessel after this experiment was not ingot-like but fragmented debris. As a possible mechanism for such a debris shape, Fuel-Coolant Interaction (FCI) at the molten alumina jet impingement on the bottom of the test vessel might have promoted jet fragmentation, and heat exchange by sodium inflow and outflow through the flow holes might have contributed to effective cooling of molten alumina.
Improvement of Transverse Leakage Term Based on Fourier Series Expansion in the 2-D/1-D Method
Authors: Zhu Kaijie , Kong Boran , Hou Jie , Zhang Han , Guo Jiong , Li Fu
Published: October 2021

The 2-D/1-D concept is widely used in various neutron transport codes to obtain sub-pin level flux distribution. The 3D problem is decomposed into 2-D plane and 1-D problems in order to solve the time-consuming problem of direct transport calculation. The method of characteristics (MOC) is usually used in radial 2-D transport calculation in order to capture radial complex geometry. The discrete ordinate (SN) method is selected as the axial 1-D transport sweeper in this work. The two solvers are coupled by transverse leakage terms. Therefore, the accuracy of 2-D/1-D method highly depends on the approximation of the transverse leakage term. For example, in KUCA benchmark test, the isotropic approximation will introduce more than 700 pcm errors to the eigenvalue since the angular correlation of the leakage term is ignored. However, the memory consumption of storing strictly angle related leakage terms is too large. In this work, an alternative method is proposed. The Fourier series expansion is used to approximate the leakage terms, while only a few moments need to be stored. Several benchmark problems have been tested to verify the accuracy of the Fourier-series-based transverse leakage terms. The results show that the improved leakage term can significantly improve the accuracy of eigenvalue with relatively low memory consumption.
Neutronic/Thermal-Hydraulic Coupling Analysis of Xi'an Pulsed Reactor Based on RMC and COBRA-TF
Authors: Li Ruihan , Cao Jianzhu , Wang Lipeng , Zhang Xinyi , Guo Xiaoyu , Liang Jingang
Published: October 2021

This article carries out neutron-hydraulic coupling research of Xi’an Pulsed Reactor (XAPR). The coupling is based on Monte Carlo neutron transport code RMC and sub-channel thermal-hydraulic code COBRA-TF (CTF) because of the high accuracy of Monte Carlo method and the high efficiency of subchannel method. The interface code is developed in python for data transfer between RMC and CTF. The coupling simulation is firstly performed under 1MW, 1.5MW and 2MW steady state. The temperature and power distribution are obtained. The results are compared with the experimental data. Temperature of the fuel rod has a difference in the range of 0.6 °C to 29 °C with the experimental values. Then we perform burnup simulation of XAPR running for 3600 days continuously under the power of 2MW and obtain the neutron and thermal-hydraulic parameters with burnup. Two coupling schemes are applied in the burnup simulation. One scheme is to make neutron-hydraulic coupling using both RMC and CTF in each burn step and the other is only coupling in the first and last burn step while calculation in other steps is only carried out by RMC. The result show great difference between the two schemes. Though currently there are no experimental data for this model to verify, the result obtained using the latter scheme is obviously unreasonable, implying the necessity of making neutron-hydraulic coupling in each burn step.
The Vertical Leaching Migration Research on 137Cs in Soil Around Shidaowan Plant of CAP1400
Authors: Zhang Qiong
Published: October 2021

The risk of radioactive material leakage caused by nuclear accidents increased with the increasing of number of Nuclear Power Plants in China. One of the serious threat of radiation harm to the human body is believed to be 137Cs. It can exist in the environment for a long time, due to the half-life of which is as long as about 30 years. In this research, the brown soil and aeolian sandy soil were selected as two kinds of classic soil around the site of Shidaowan demonstration plant of CAP1400 to carry out the 137Cs migration model experiments. The source of radioactivity was put on the 16 of experiment columns that were filled by undisturbed soil, the simulated raining weather was according to the local rainfall amount with two sprinklers, and the sunlight was replaced by fluorescent lamp. The result showed that the vertical migration model of radionuclides in soil is one-dimensional convective dispersion equation. three-year experiments showed that most of 137Cs in soil were distributed in the range of 0–4cm. The simulation results using the Hydrus 1D with 10 years that most of 137Cs in soil were distributed in the range of 0–10cm, so the nuclear accident caused by the serious nuclides have little impact on groundwater.
Verification of PWR-Core Analysis Code CORAL Using VERA Core Physics Benchmark
Authors: Yang Wen , Chao Fei , Qiu Jinrong , Li Xing , Liu Baolin
Published: October 2021

Three dimensional PWR-core analysis code CORAL developed by Wuhan Second Ship Design and Research Institute, which provides all functions required by PWR-core analysis calculation. These functions are neutron diffusion within the core and reflector, macroscopic depletion or microscopic depletion calculation analysis, multi-channel or sub-channel thermal-hydraulic analysis, one-dimensional heat transfer from nuclear fuel to the coolant, critical search by boron concentration or control rod position, integral and differential worth of neutron absorbers, neutron kinetics parameters for transient analysis, in-core neutron detector response simulation etc. CORAL is convenient to update and maintain in consider of modular, object-oriented programming technology. In order to verify the computational capabilities of the reactor core analysis software and methods, the US CASL project proposed the VERA reactor physics benchmark problem. This benchmark problem is based on the initial loading of Watts Bar Nuclear unit 1 as a model ranging from a simple 2D pin problem cell to the full cycle depletion and refueling of problem a 3D reactor core configuration. Aiming at the VERA benchmark problems, physics calculations are performed using the CORAL code, and the results of effective multiplication factor, assembly power distribution, control rod worth value and reactivity coefficient are obtained. By comparing with the KENO results provided in the benchmark problems, the calculation results of CORAL code are in good agreement. This shows that the CORAL code has the ability to calculate from 2D lattice to the 3D reactor core, and its computational accuracy is basically equivalent to the KENO code.