bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultradeep targeted sequencing of circulating tumor DNA in plasma of early and advanced breast cancer
Authors: Chin Yoon Ming , Takahashi Yoko , Chan Hiu Ting , Otaki Masumi , Fujishima Makoto , Shibayama Tomoko , Miki Yoshio , Ueno Takayuki , Nakamura Yusuke , Low Siew‐Kee
Published: October 2020

We present a study to evaluate the feasibility and clinical utility of amplicon‐based Oncomine Pan‐Cancer cell‐free assay to detect circulating tumor DNA (ctDNA) in patients with early or advanced breast cancer. In this study, 109 early and metastatic breast cancer patients were recruited before the initiation of treatment. ctDNA mutation profiles were assessed through unique molecular tagging (UMT) and ultradeep next generation sequencing (NGS). For patients with mutations, DNA from corresponding white blood cells (WBC) was sequenced to exclude variants of clonal‐hematopoietic (CH) origin. UMT targeted sequencing from plasma of 109 patients achieved a median total coverage of 55 498X and a median molecular coverage of 4187X. Among 53 ctDNA positive samples, 38% were mutation positive by WBC sequencing, indicating potentially false‐positive results contributed by CH origin. Prevalence of CH‐related mutations was associated with age (P = 7.51 × 10−4). After exclusion of CH mutations, ctDNA detection rates were 37% for local or locally advanced breast cancer (stage I‐III) and 81% for metastatic or recurrent breast cancer. The ctDNA detection rate correlated with disease stage (P = 2.60 × 10−4), nodal spread (P = 6.49 × 10−3) and the status of distant metastases (P = 5.00 × 10−4). ctDNA variants were detected mostly in TP53, PIK3CA and AKT1 genes, with variants showing therapeutic relevance. This pilot study endorses the use of targeted NGS for non‐invasive molecular profiling of breast cancer. Paired sequencing of plasma ctDNA and WBC should be implemented to improve accurate interpretation of liquid biopsy.
N‐pyridinylbenzamides: an isosteric approach towards new antimycobacterial compounds
Authors: Nawrot Daria , Suchánková Eliška , Janďourek Ondřej , Konečná Klára , Bárta Pavel , Doležal Martin , Zitko Jan
Published: October 2020

A series of N‐pyridinylbenzamides was designed and prepared to investigate the influence of isosterism and positional isomerism on antimycobacterial activity. Comparison to previously published isosteric N‐pyrazinylbenzamides was made as an attempt to draw structure–activity relationships in such type of compounds. In total, we prepared 44 different compounds, out of which fourteen had minimum inhibitory concentration (MIC) values against Mycobacterium tuberculosis H37Ra below 31.25 µg/ml, most promising being N‐(5‐chloropyridin‐2‐yl)‐3‐(trifluoromethyl)benzamide (23) and N‐(6‐chloropyridin‐2‐yl)‐3‐(trifluoromethyl)benzamide (24) with MIC = 7.81 µg/ml (26 µm). Five compounds showed broad‐spectrum antimycobacterial activity against M. tuberculosis H37Ra, M. smegmatis and M. aurum. N‐(pyridin‐2‐yl)benzamides were generally more active than N‐(pyridin‐3‐yl)benzamides, indicating that N‐1 in the parental structure of N‐pyrazinylbenzamides might be more important for antimycobacterial activity than N‐4. Marginal antibacterial and antifungal activity was observed for title compounds. The hepatotoxicity of title compounds was assessed in vitro on hepatocellular carcinoma cell line HepG2, and they may be considered non‐toxic (22 compounds with IC50 over 200 µm).
Comparing outcomes of children and youth with fetal alcohol spectrum disorder (FASD) in the child welfare system to those in other living situations in Canada: Results from the Canadian National FASD Database
Authors: Burns Jessica , Badry Dorothy E. , Harding Kelly D. , Roberts Nicole , Unsworth Kathy , Cook Jocelynn L.
Published: October 2020

Aims

The current study aimed to explore differences in adverse outcomes between youth and adolescents with fetal alcohol spectrum disorder (FASD) living in child welfare care (i.e., foster care or group home) with those living with their biological parent(s) or with adoptive or other family member(s) in Canada.

Methods

Data gathered from the Canadian National FASD Database were used for analysis. A total of 665 youth and adolescents with a clinical diagnosis of FASD under the age of 18 living in child welfare care, with biological, adoptive or other family members, were included in the sample. Key areas examined included living situation, legal problems, experience of sexual or physical abuse, mental health (anxiety, conduct disorder, mood disorder and post‐traumatic stress disorder) and suicidal ideation. Descriptive statistics and chi‐square comparisons were utilized to explore these differences.

Results

Results revealed a significantly higher rate of reported sexual and physical abuse among individuals in child welfare care compared with those living with biological parents or with adoptive or other family member(s). Rates of difficulty with the law were also higher among those in child welfare care compared with adoptive/other family members. Conversely, the rate of mood disorders was significantly higher among those living with adoptive/other family members compared with child welfare care. Results highlight similar rates of reported suicidal ideation/attempts across all living situations, as well as mental health concerns.

Conclusions

Results offer rare insight into the lives of youth and adolescents under age 18 with diagnosed FASD who reside in child welfare care in contrast to those living with biological parent(s) or with adoptive or other family members. These findings increase our awareness of the complexity of mental health concerns and suicide risk across all living environments. Results have further implications for policy, practice and clinical intervention.
Prevalence, concomitant reactions, and factors associated with fragrance allergy in Thailand
Authors: Sukakul Thanisorn , Charoenpipatsin Norramon , Svedman Cecilia , Boonchai Waranya
Published: October 2020

Background

Fragrances are the most common cause of cosmetic contact allergy. Up‐to‐date information on contact allergy frequencies and relevance aids primary and secondary preventive measures.

Objectives

To determine the prevalence, associated factors, and concomitant reactions in fragrance allergy among Thais.

Methods

This retrospective study collected data from 2012 to 2019. The patient characteristics of fragrance and nonfragrance allergy groups were compared. Concurrent positive reactions to fragrance allergens (fragrance mix [FM] I, FM II, Myroxylon pereirae resin and hydroxyisohexyl 3‐cyclohexene carboxaldehyde) and other baseline‐series allergens were analysed.

Results

Of 1032 patients, 175 (17.0%) had fragrance allergy, with 57.7% of clinical relevance. FM I showed the highest prevalence (9.4%). The associated factors were being elderly, lesions on the extremities, metal allergy history, and long dermatitis duration. Contact allergies to epoxy resin and Compositae plants were significantly associated with fragrance allergy with an odds ratio of 5.95 (95% confidence interval [CI]: 5.21‐6.80) and an odds ratio of 4.42 (95% CI: 1.58‐12.36), respectively. No significant associations between colophonium (previously proposed as a fragrance marker) and fragrance allergens were found.

Conclusions

The prevalence of fragrance contact allergy remains high and should be considered in old patients presenting with long‐standing eczema on the extremities. Unlike reports from other countries, varied, significant, concomitant reactions were observed.
A new approach to flame‐retardant cellulosic fabrics in an environmentally safe manner
Authors: Lewis David M. , Hawkes Jamie A. , Hawkes Liangyu , Mama John
Published: October 2020

This article investigates reacting potassium salts of phosphorous‐containing acids in the presence of urea with cotton cellulose under thermosol conditions (pH 5, 185 °C) to esterify the cellulose and produce a flame‐retardant effect. Attenuated total reflectance‐Fourier‐transform infrared (ATR‐FTIR) spectroscopy confirmed chemical modification of the cotton cellulose, where only the phosphite salt formed a covalently bonded cellulose ester (confirmed by flammability tests). Urea plays a vital role; decomposing to ammonia and isocyanic acid (the reactive intermediate) and it is the isocyanic acid/phosphite anion addition compound that reacts with cellulose hydroxyl groups to form the required ester. ATR‐FTIR analysis showed that phosphate and hypophosphite salts did not react with cellulose and thus gave no flame‐resist effect. Whilst the esterification of cellulose introduces phosphorous onto the cellulose, in order to meet more severe work‐wear laundry standards it was necessary to further incorporate a nitrogen species by addition of a cationic polymer. To develop a one shot “all‐in” process the possibility of simultaneously bonding nitrogen through carbodimide chemistry is researched, with initial promising trials demonstrated. Many after‐treatments of dyed fabrics can cause colour shifts due to interactions with the chromophores. Azo dyes, for example, are particularly susceptible to attack by the formaldehyde produced during the Pyrovatex process or the reducing nature of the Proban process, both resulting in a colour change. An advantage of the novel phosphite/urea flame‐retardant system presented herein, is that the system is less aggressive which allows the possibility of using reactive dyes to produce a bright and wide shade range as the results demonstrate.
Clinical profiles of post‐load glucose subgroups and their association with glycaemic traits over time: An IMI‐DIRECT study
Authors: Obura M. , Beulens J. W. J. , Slieker R. , Koopman A. D. M. , Hoekstra T. , Nijpels G. , Elders P. , Dekker J. M. , Koivula R. W. , Kurbasic A. , Laakso M. , Hansen T. H. , Ridderstråle M. , Hansen T. , Pavo I. , Forgie I. , Jablonka B. , Ruetten H. , Mari A. , McCarthy M. I. , Walker M. , McDonald T. J. , Perry M. H. , Pearson E. R. , Franks P. W. , ‘t Hart L. M. , Rutters F. ,   the IMI‐DIRECT Consortium
Published: October 2020

Aim

To examine the hypothesis that, based on their glucose curves during a seven‐point oral glucose tolerance test, people at elevated type 2 diabetes risk can be divided into subgroups with different clinical profiles at baseline and different degrees of subsequent glycaemic deterioration.

Methods

We included 2126 participants at elevated type 2 diabetes risk from the Diabetes Research on Patient Stratification (IMI‐DIRECT) study. Latent class trajectory analysis was used to identify subgroups from a seven‐point oral glucose tolerance test at baseline and follow‐up. Linear models quantified the associations between the subgroups with glycaemic traits at baseline and 18 months.

Results

At baseline, we identified four glucose curve subgroups, labelled in order of increasing peak levels as 1–4. Participants in Subgroups 2–4, were more likely to have higher insulin resistance (homeostatic model assessment) and a lower Matsuda index, than those in Subgroup 1. Overall, participants in Subgroups 3 and 4, had higher glycaemic trait values, with the exception of the Matsuda and insulinogenic indices. At 18 months, change in homeostatic model assessment of insulin resistance was higher in Subgroup 4 (β = 0.36, 95% CI 0.13–0.58), Subgroup 3 (β = 0.30; 95% CI 0.10–0.50) and Subgroup 2 (β = 0.18; 95% CI 0.04–0.32), compared to Subgroup 1. The same was observed for C‐peptide and insulin. Five subgroups were identified at follow‐up, and the majority of participants remained in the same subgroup or progressed to higher peak subgroups after 18 months.

Conclusions

Using data from a frequently sampled oral glucose tolerance test, glucose curve patterns associated with different clinical characteristics and different rates of subsequent glycaemic deterioration can be identified.
Atomic structure of and valine binding to the regulatory ACT domain of the Mycobacterium tuberculosis Rel protein
Authors: Shin Joon , Singal Bharti , Sony Subramanian Manimekalai Malathy , Wei Chen Ming , Ragunathan Priya , Grüber Gerhard
Published: October 2020

The stringent response, regulated by the bifunctional (p)ppGpp synthetase/hydrolase Rel in mycobacteria, is critical for long‐term survival of the drug‐tolerant dormant state of Mycobacterium tuberculosis. During amino acid starvation, MtRel senses a drop in amino acid concentration and synthesizes the messengers pppGpp and ppGpp, collectively called (p)ppGpp. Here, we investigate the role of the regulatory ‘Aspartokinase, Chorismate mutase and TyrA’ (ACT) domain in MtRel. Using NMR spectroscopy approaches, we report the high‐resolution structure of dimeric MtRel ACT which selectively binds to valine out of all other branched‐chain amino acids tested. A set of MtRel ACT mutants were generated to identify the residues required for maintaining the head‐to‐tail dimer. Through NMR titrations, we determined the crucial residues for binding of valine and show structural rearrangement of the MtRel ACT dimer in the presence of valine. This study suggests the direct involvement of amino acids in (p)ppGpp accumulation mediated by MtRel independent to interactions with stalled ribosomes.

Database

Structural data are available in the PDB database under the accession number 6LXG.
Phosphorus addition decreases microbial residual contribution to soil organic carbon pool in a tropical coastal forest
Authors: Yuan Ye , Li Yue , Mou Zhijian , Kuang Luhui , Wu Wenjia , Zhang Jing , Wang Faming , Hui Dafeng , Peñuelas Josep , Sardans Jordi , Lambers Hans , Wang Jun , Kuang Yuanwen , Li Zhi’an , Liu Zhanfeng
Published: October 2020

The soil nitrogen (N) and phosphorus (P) availability often constrains soil carbon (C) pool, and elevated N deposition could further intensify soil P limitation, which may affect soil C cycling in these N‐rich and P‐poor ecosystems. Soil microbial residues may not only affect soil organic carbon (SOC) pool but also impact SOC stability through soil aggregation. However, how soil nutrient availability and aggregate fractions affect microbial residues and the microbial residue contribution to SOC is still not well understood. We took advantage of a 10‐year field fertilization experiment to investigate the effects of nutrient additions, soil aggregate fractions, and their interactions on the concentrations of soil microbial residues and their contribution to SOC accumulation in a tropical coastal forest. We found that continuous P addition greatly decreased the concentrations of microbial residues and their contribution to SOC, whereas N addition had no significant effect. The P‐stimulated decreases in microbial residues and their contribution to SOC were presumably due to enhanced recycling of microbial residues via increased activity of residue‐decomposing enzymes. The interactive effects between soil aggregate fraction and nutrient addition were not significant, suggesting a weak role of physical protection by soil aggregates in mediating microbial responses to altered soil nutrient availability. Our data suggest that the mechanisms driving microbial residue responses to increased N and P availability might be different, and the P‐induced decrease in the contribution of microbial residues might be unfavorable for the stability of SOC in N‐rich and P‐poor tropical forests. Such information is critical for understanding the role of tropical forests in the global carbon cycle.
Use of Dementia Assessment Sheet for Community‐based Integrated Care System 8‐items (DASC‐8) for the screening of frailty and components of comprehensive geriatric assessment
Authors: Toyoshima Kenji , Araki Atsushi , Tamura Yoshiaki , Ishikawa Joji , Kodera Remi , Oba Kazuhito , Chiba Yuko , Awata Shuichi
Published: October 2020

Aim

We examined whether the Dementia Assessment Sheet for Community‐based Integrated Care System 8‐items (DASC‐8) is useful for screening frailty and as a comprehensive geriatric assessment (CGA).

Methods

Outpatients (N = 431; 269 women; Mage = 78.9 ± 6.8 years) with cardiometabolic disease from a frailty clinic participated. Frailty status was assessed using modified Cardiovascular Health Study criteria, the Clinical Frailty Scale and the Kihon Checklist. Cognition, higher‐level activities of daily living, sarcopenia, physical activities, depression, nutrition, medication adherence, social network and quality of life were assessed as CGA components. We examined the association of DASC‐8 category with frailty or CGA components using multiple logistic regression analyses, adjusted for age and sex.

Results

Most participants (n = 310, 71.9%) were in Category I, 90 (20.9%) were in Category II and 31 (7.1%) were in Category III. There were no significant differences in sex, body mass index, or past medical history, except regarding age or cerebral infarction. Logistic regression analyses showed that, for all definitions of frailty, the odds ratios of frailty significantly increased as category progressed. Cognitive function, higher‐level activities of daily living, handgrip strength, gait speed, physical activities, medication adherence, social network and quality of life decreased as the category increased. Although depressive tendency increased in Category II, there was no significant difference in muscle mass or prevalence of sarcopenia among the categories. Malnutrition was observed in Category III.

Conclusions

DASC‐8 category was associated with frailty and several CGA components in older patients with cardiometabolic disease. Geriatr Gerontol Int 2020; 20: 1157–1163.
Feasibility of non‐destructive evaluation for apple crispness based on portable acoustic signal
Authors: Liu Yang , Cai Mingjin , Zhang Wangyou , Feng Wanling , Sun Xingyuan , Zhang Yang , Zhou Hongli
Published: October 2020

In this paper, apple crispness was evaluated by sensory evaluation and compared with non‐destructive measurements of portable acoustic signal to discuss the feasibility of non‐destructive evaluation for apple crispness based on portable acoustic signal. Acoustic eigenvalues from the acoustic signal were processed by time domain and Hilbert–Huang transform (HHT), followed by analysing the correlations with apple crispness that had been evaluated via sensory evaluation. Multiple linear regression (MLR) and artificial neural network (ANN) were applied to predict apple crispness. The results proved that crispness correlates significantly (P < 0.01) with four acoustic eigenvalues, including waveform index, sound intensity, energy of low frequency and energy of high frequency. The average relative error of apple crispness predicted by ANN was 1.42 ± 1.9%, remarkably lower (P < 0.01) that of MLR (6.79 ± 5.64%), implying that the model predicted by ANN is more accurate than that of MLR.
Comparative analysis and antibacterial properties of thermally sintered apatites with varied processing conditions
Authors: Jahangir Mehnaz Urbee , Islam Farhana , Wong Siew Yee , Jahan Rumana A. , Matin Md Abdul , Li Xu , Arafat M. Tarik
Published: October 2020

Hydroxyapatite (HA) and biphasic hydroxyapatite/beta‐tricalcium phosphate (biphasic HA/β‐TCP) were synthesized using thermal sintering. The parameters‐ sintering temperature (600°C, 900°C, and 1200°C), biological source used (fish bone, egg shells, and fish scales), and soaking time (2, 6, and 10 hours) were permuted to study their effects on the properties of the resultant apatite. Morphological study revealed that the smallest (60 nm) spherical particle and the largest (470 nm) irregular shaped particle were obtained from the fish bone sample sintered at 600°C and at 1200°C respectively. FTIR and XRD results showed that as the sintering temperature is increased, the phase transformation from HA to β‐TCP takes place. Only the final products from fishbone sample at 600°C are pure carbonated HA. The crystallinity of synthesized particles ranged from 79% to 98%. Soaking time has no effect on phase composition of the apatite but has significant effect on crystallite size; increase in soaking time increases crystallite size and particle shape becomes more spherical. Interestingly, the fish bone sample sintered at 900°C has higher crystallinity and crystallite size compared to the fish scale sample sintered at the same temperature. EDX confirmed that non‐stoichiometric apatite with Ca/P ratio ranging from 1.47 to 1.91 can be obtained by varying the sintering conditions. The antibacterial test revealed that both calcium apatite obtained from fish bones and fish scales have inhibited bacterial growth; apatite from fish bone works faster than fish scales. The in vitro cytotoxicity test ensured that all the calcium apatite except for eggshell are non‐cytotoxic. Thus, apatite with excellent microbial activity can be obtained by using fish wastes, and by tuning the sintering parameters, the apatite with desired types and properties can be synthesized for different biomedical applications.
Exploiting differences in the energy budget among C4 subtypes to improve crop productivity
Authors: Yin Xinyou , Struik Paul C.
Published: October 2020

C4 crops of agricultural importance all belong to the NADP‐malic enzyme (ME) subtype, and this subtype has been the template for C4 introductions into C3 crops, like rice, to improve their productivity. However, the ATP cost for the C4 cycle in both NADP‐ME and NAD‐ME subtypes accounts for > 40% of the total ATP requirement for CO2 assimilation. These high ATP costs, and the associated need for intense cyclic electron transport and low intrinsic quantum yield , are major constraints in realizing strong improvements of canopy photosynthesis and crop productivity. Based on mathematical modelling, we propose a C4 ideotype that utilizes low chloroplastic ATP requirements present in the nondomesticated phosphoenolpyruvate carboxykinase (PEP‐CK) subtype. The ideotype is a mixed form of NAD(P)‐ME and PEP‐CK types, requires no cyclic electron transport under low irradiances, and its theoretical is c. 25% higher than that of a C4 crop type. Its cell‐type‐specific ATP and NADPH requirements can be fulfilled by local energy production. The ideotype is projected to have c. 10% yield advantage over NADP‐ME‐type crops and > 50% advantage over C3 counterparts. The ideotype provides a unique (theoretical) case where could be improved, thereby paving a new avenue for improving photosynthesis in both C3 and C4 crops.
Comment on “Olley and Pakes‐style Production Function Estimators with Firm Fixed Effects”*
Authors: Ackerberg Daniel A.
Published: October 2020

In this comment I illustrate that in the model of (Lee et al. (2019). Oxford Bulletin of Economics and Statistics. Vol. 81, pp. 80–97), firm profit maximizing implies that Assumption 2 and Equation 14 may be contradictory. More specifically, there is generally a contradiction when investment is used as the control variable, but there is generally not a contradiction when a static input like material input is used as the control variable (both types of control variables are discussed in Lee et al.). While the Lee et al. model and techniques are an interesting way to incorporate fixed effects into Olley and Pakes‐style production function estimators, this observation suggests that their application should be restricted to cases where static inputs are used as control variables.
A plea for making brown bandages stick
Authors: Oyesiku Linda O.
Published: October 2020

The act of healing is a uniquely humanizing experience ubiquitously symbolized by the application of a bandage, an action that occurs daily in dermatology and pediatric clinics. The beige bandages we use in clinics are merely a visible symbol and reinforcement of what is considered standard and what is a deviation from the norm. One hundred years ago, Johnson & Johnson was a pioneer in the field when they invented the adhesive bandage. One hundred years ago, they set an industry standard by creating, exporting, and upholding a normative standard for practically all adhesive bandages in medicine, including birth control and nicotine patches to nasal strips. It took one hundred years after its inception and with over 100 billion Band‐Aids produced with cartoons and superheroes, and in countless forms, for the inventors of bandages to offer a multitude of skin tones. Can we as healers stick with them? Or, can we implore ourselves to decolonize our clinics with a seemingly insignificant yet powerful symbolic gesture that lets our patients know that they are seen and not deviations from the norm? The conversation of diversity and inclusion in health and healing and institutional racism is obviously much deeper and profound than adhesive bandages. However, we can choose to acknowledge and celebrate diversity and inclusion in our practices as much as we can because it is significant to all of our patients, children, and adults alike.
Dynamic Assortment Planning Under Nested Logit Models
Authors: Chen Xi , Shi Chao , Wang Yining , Zhou Yuan
Published: October 2020

We study a stylized dynamic assortment planning problem during a selling season of finite length T. At each time period, the seller offers an arriving customer an assortment of substitutable products and the customer makes the purchase among offered products according to a discrete choice model. The goal of the seller is to maximize the expected revenue, or equivalently, to minimize the worst‐case expected regret. One key challenge is that utilities of products are unknown to the seller and need to be learned. Although the dynamic assortment planning problem has received increasing attention in revenue management, most existing work is based on the multinomial logit choice models (MNL). In this paper, we study the problem of dynamic assortment planning under a more general choice model—the nested logit model, which models hierarchical choice behavior and is “the most widely used member of the GEV (generalized extreme value) family” (Train 2009). By leveraging the revenue‐ordered structure of the optimal assortment within each nest, we develop a novel upper confidence bound (UCB) policy with an aggregated estimation scheme. Our policy simultaneously learns customers’ choice behavior and makes dynamic decisions on assortments based on the current knowledge. It achieves the accumulated regret at the order of [Formula: see text], where M is the number of nests and N is the number of products in each nest. We further provide a lower bound result of [Formula: see text], which shows the near optimality of the upper bound when T is much larger than M and N. When the number of items per nest N is large, we further provide a discretization heuristic for better performance of our algorithm. Numerical results are presented to demonstrate the empirical performance of our proposed algorithms.
The many shades of ‘openness’: an application of item response theory to open innovation research
Authors: Marullo Cristina , Martelli Irene , Di Minin Alberto
Published: October 2020

This study addresses one of the most basic research questions investigated in the Open Innovation (OI) literature: how open are firms? This question has remained partially unanswered given the challenges encountered by empirical research in assessing the relevance of specific OI practices within the OI model, as well as the types of activities perceived by managers as OI benefits or concerns. To provide an answer to this question, we suggest a framework using Item Response Theory to improve over current measures of firms' openness and test it on a sample of 383 technology‐based SMEs. Our theoretical model conceives openness as an instance of how firms make decisions regarding the adoption of different OI practices based on their evaluation of OI benefits and concerns. Focusing on the relationship between firm‐level differences in terms of openness and the types of OI practices adopted by these firms, we show that significantly different levels of ‘OI maturity’ are required to broaden the scope of external partnerships and to shift from non‐pecuniary OI modes (relation‐based approaches) toward pecuniary (transaction‐based) practices. Our results have relevant implications for the OI literature and provide new managerial insight into OI adoption.
Consociationalism is Dead! Long Live Zombie Power‐Sharing!
Authors: Nagle John
Published: October 2020

Scholars argue that consociationalism has become the preferred institutional tool of choice for the international community when seeking an end to civil war. This paper argues that consociationalism is increasingly becoming redundant as an institutional apparatus to end violent conflict linked to intra‐state conflict. Over the last few decades divided societies have been subjected to consociational influence. In many places consociational institutions have long since ceased functioning in a way that is healthy for the body politic, yet somehow consociationalism remains dominant both for policy prescription and in academic thinking. While consociationalism was once understood by institutional designers to be transformative, facilitating a transition to a less sectarian system, the reverse is true. Rather than transformation and change, consociations tend to develop ossified properties rendering them resistant to practically any reform. Summoning the image of the zombie, I note that consociationalism is ‘dead but dominant’ and has to defend itself through increasingly authoritarian statecraft. Consociationalism is thus neither dead nor alive, but walking dead, listlessly stumbling from one crisis to the next. Each crisis is experienced contingently with the feeling that something could happen – that something could change – very soon, even as routine prevails in the face of an increasingly defensive state.
Afrotropics on the wing: phylogenomics and historical biogeography of awl and policeman skippers
Authors: Toussaint Emmanuel F.A. , Chiba Hideyuki , Yago Masaya , Dexter Kelly M. , Warren Andrew D. , Storer Caroline , Lohman David J. , Kawahara Akito Y.
Published: October 2020

The Old‐World Tropics encompass many unique biomes and associated biotas shaped by drastic climate and geological changes throughout the Cenozoic. Disjunct distributions of clades between the Afrotropics and the Oriental regions are testament to these changes. Awl and policeman skippers (Hesperiidae: Coeliadinae) are disjunctly distributed with some genera endemic to the Afrotropics and others restricted to the Oriental and Australian regions. We reconstruct the phylogeny of these butterflies using target exon capture phylogenomics. We also generate a dated framework for this clade that uses the putatively oldest known butterfly fossil to estimate the historical biogeography of Coeliadinae using a model‐based approach. We infer a stable and robust phylogeny for the subfamily, with all but one Afrotropical lineage forming a derived clade. The African genus Pyrrhiades syn. nov. is placed in synonymy with Coeliades to accommodate the new phylogeny. Our comparative dating exercise casts doubt on the assignment of the fossil Protocoeliades kristenseni as a derived Coeliadinae and suggests, along with our biogeographic estimation, a split of Coeliadinae from the rest of skippers in the Palaeocene ca. 70 million years ago. The origin of crown Coeliadinae skippers is estimated in Indomalaya during the late Eocene ca. 36 million years ago, with subsequent Oligocene colonisation events toward the Australian region and the Afrotropics. Colonisation of the Afrotropics from the Indian region occurred during climatic transition, associated biome shifts, and the closure of the Tethys Ocean, which likely allowed geodispersal through the Arabian Peninsula. The current disjunct distribution of Coeliadinae in the Old World Tropics may result from the emergence of savannahs in the Miocene that progressively replaced woodlands and forests in the Arabian Peninsula and western Asia. Coeliadinae skippers are almost exclusively dicot feeders and were likely extirpated as grasslands became dominant, resulting in the present‐day disjunct distribution of these butterflies.
The Link Between Ethnic Segregation and Socio‐Economic Status: An Activity Space Approach
Authors: Järv Olle , Masso Anu , Silm Siiri , Ahas Rein
Published: October 2020

The extent to which ethnic segregation results from differences in socio‐economic factors remains a seminal topic of debate. The growing literature demonstrating the multifaceted phenomenon of segregation urges more focus on individuals’ spatial and social interactions. We applied an activity space approach and considered ethnic differences in individuals’ activity spaces as an indicator of spatial segregation. We used mobile phone and survey datasets in Estonia. We show that place‐based segregation indices derived from both datasets indicate similar levels of ethnic segregation. From an activity space perspective, the results show that the main socio‐economic factor affecting the extensity of activity spaces is self‐estimated social status rather than education and income. Results show that ethnic inequality in spatial behaviour is not straightforward, but rather that it is linked to how individuals position themselves in society. We argue that socio‐economic factors need to be controlled to examine ethnic segregation from activity space perspective.
Toward Industrial Applicability of DNB Predictions in CFD With Improved Wall Boiling Models
Authors: Feng Jinyong , Skirpan Zachary , Baglietto Emilio
Published: October 2020

The design of Pressurized Water Reactor (PWR) fuel has to rely on costly prototypical experimental campaigns, due to the inherent limitations of legacy lumped-parameter thermal-hydraulics codes. By resolving the fine spatial scales, computational fluid dynamics (CFD) methods offer the opportunity of delivering improved fuel design, taking full advantage of three-dimensional mixing and turbulence control, but must extend their predictive capabilities to multiphase conditions up to DNB, where the maturity and accuracy of the methods is still developing. In this paper, the closures developed within the Eulerian-Eulerian two-fluid model framework are assembled and extended to a general boiling formulation to deliver prediction of DNB at reactor conditions. The classic heat flux partitioning approach is advanced through selection of optimal closures for interaction length scale, nucleation site density, and bubble departure diameter, and further extended though the addition of a consistent DNB detection criterion, to reflect the near wall two phase characteristics. Assessment is performed at 138 bar against the experimental dataset for vertical pipe, where the inlet subcooling ranges from 1 to 150 K and the mass flux varies from 600 kg/(m2.s) to 2650 kg/(m2.s). The presented closures demonstrate consistent agreement with the experimental data, in particular in light of the calibration free application, while further work is ongoing to close the remaining gap and support the introduction of further modeling improvements.
Simulation of ENACCEF2 Premixed Hydrogen-Air Mixture Deflagration Experiment Using OpenFOAM
Authors: Jaseliūnaitė Justina , Povilaitis Mantas
Published: October 2020

During a severe accident in a nuclear power plant, hydrogen would be generated due to the oxidation of metallic components in steam atmosphere. In the containment hydrogen would form a combustible mixture, posing a deflagration or even detonation risk threatening the integrity of the containment. In order to estimate possible loads generated by the hydrogen combustion, reliable numerical tools are needed to simulate the deflagration process. Recently, the French MITHYGENE project consortium and the European Technical Safety Organization Network (ETSON) organized a benchmark on hydrogen combustion to identify the current level of the computational tools in the area of hydrogen combustion simulation under a severe accident typical conditions. The benchmark was based on the experiments performed in the ENACCEF2 facility.

This paper presents post-benchmark simulations of the selected ENACCEF2 facility premixed hydrogen combustion experiment. The presented simulations were performed using a custom-built turbulent combustion OpenFOAM solver based on the progress variable model.

Turbulent flame acceleration phase in the acceleration tube was well predicted. Furthermore, the simulations were able to capture the interaction between the flame and shock wave which was generated by the turbulent deflagration flame and reflected at the end of the ENACCEF2 tube. The overall numerical results show good agreement with the qualitative and quantitative behavior of the velocity results and flame front propagation.
Effect of Containment Vessel’s Size Scale on the Aerosol Spray Scavenging Efficiency With Water Mist
Authors: Liang Hui , Zhou Qian , Erkan Nejdet , Suzuki Shunichi , Leblois Yohan , Gelain Thomas , Porcheron Emmanuel
Published: October 2020

In the foreseen decommissioning and debris removal plans of the damaged Fukushima Daiichi reactors, the fuel debris will be broken into small pieces using laser or mechanical cutting techniques prior to removing them from the reactor buildings. Regardless of the technique to be employed, submicron radioactive aerosol particles will be generated and dispersed in the gas space of primary containment vessel during cutting operations. The water spray system has been proven to be an applicable method in removing aerosol particles. However, it cannot remove Greenfield-gap aerosol particles (with diameters between 0.1–1 μm) so effectively. To solve this problem, a new agglomeration method by addition of water mist before spray injection was developed. With preexisting water mist, aerosol particles were expected to aggregate with water mist and form larger-sized agglomerated aerosol-mist particles, which increased the effect of inertial impaction mechanism leading to higher scavenging efficiency. The new method has been verified to be capable of improving the spray scavenging efficiency for the Greenfield gap particles by conducting aerosol scavenging experiments without and with mist in the newly built UTARTS facility in the University of Tokyo. The experiment results showed that the aerosol removal rate increased along with the increasing of mist concentration level. To verify the new agglomeration method in different experiment facilities and to investigate the effects of vessel’s size scale on aerosol collection efficiency, similar experiments were repeated in the TOSQAN facility of IRSN, France. Though the cylindrical vessel in two facilities have same internal diameter, the vessel’s height of TOSQAN facility is 4.8 m, which is larger than the one in the UTARTS facility (2.5 m). The experiment results in TOSQAN facility also showed that water mist has potential to improve aerosol spray scavenging efficiency. The corresponding numerical simulations about aerosol removal by spray droplets without mist in both UTARTS and TOSQAN facilities were conducted to better understand the aerosol removal process, including time evolution of aerosol mass fraction and flow field of the gas phase.
The Experimental Study of Single Droplet Impinging on an Inclined Heated Wall
Authors: Tian Wenlong , Zhang Huang , Liu Qianfeng , Hu Guang , He Wen
Published: October 2020

We investigated a single droplet impinging on an inclined heated wall with different inclination angles. A high-speed camera was used to observe this impinging process at 10000 frames / second. The phenomena of the droplet spreading, shrinking, rebounding, boiling, break-up and splashing were observed. The effects of the wall temperature (Tw, 40–262 °C), the Weber number of the droplet (Wed, 0.66–589) and the wall inclination angle (α, 0–45.6°) on the spreading behavior of the droplet after impinging on the wall were analyzed. Energy conservation equation was used to analyze experimental results. The results show that increasing the inclination angle of the wall is beneficial to the forward spreading of the droplet along the wall, but not to the downward spreading. When α > 45.6°, the droplet will break through the flow resistance of the wall and slide down all the time. The increase of the wall temperature and the Weber number of the droplet is beneficial to the backward and forward spreading of the droplet. Increasing α, increasing Tw and decreasing Wed will promote the shrinking of the droplet after spreading. In addition, the experimental phenomenon also shows that the larger the wall inclination and the higher the wall temperature, the easier the droplet will break away from the wall.
Unmet Challenges to Successfully Mitigating Severe Accidents in Multi Unit CANDU Reactors
Authors: Nijhawan Sunil
Published: October 2020

One sees eerie similarities here in Canada to the cozy relationship between regulator and utilities in ‘pre-Fukushima’ Japan. Such ties are hardly limited to Canada though. The chronic degradation of real commitments to continued improvements in reactor safety systems and a decline in overall safety culture that discourages critical design reviews and willfully ignores well justified, safety critical hardware upgrades, has created alarming conditions that are likely inching us towards another nuclear disaster. Operating CANDU reactors are now close to being obsolete but have barely seen any substantive severe accident related risk reduction upgrades nine years after Fukushima, hoopla in Canada around some minor improvements and premature closure of even otherwise sparse and what were really weak regulatory ‘Fukushima Action Items’ notwithstanding.
Computational Modeling of Terry Turbine Airflow Testing to Support the Expansion of Operating Band in Beyond Design Basis Conditions
Authors: Gilkey Lindsay N. , Andrews Nathan , Ross Kyle , Solom Matthew
Published: October 2020

The performance of the Reactor Core Isolation Cooling (RCIC) system under beyond design basis event (BDBE) conditions is not well-characterized. The operating band of the RCIC system is currently specified utilizing conservative assumptions, with restrictive operational guidelines not allowing for an adequate credit of the true capability of the system. For example, it is assumed that battery power is needed for RCIC operation to maintain the reactor pressure vessel (RPV) water level — a loss of battery power is conservatively assumed to result in failure of the RCIC turbopump system in a range of safety and risk assessments. However, the accidents at Fukushima Daiichi Nuclear Power Station (FDNPS) showed that the Unit 2 RCIC did not cease to operate following loss of battery power. In fact, it continued to inject water into the RPV for nearly 3 days following the earthquake. Improved understanding of Terry turbopump operations under BDBE conditions can support enhancement of accident management procedures and guidelines, promoting more robust severe accident prevention. Therefore, the U.S. Department of Energy (DOE), U.S. nuclear industry, and international stakeholders have funded the Terry Turbine Expanded Operating Band (TTEXOB) program. This program aims to better understand RCIC operations during BDBE conditions through combined experimental and modeling efforts.

As part of the TTEXOB, airflow testing was performed at Texas A&M University (TAMU) of a small-scale ZS-1 and a full-scale GS-2 Terry turbine. This paper presents the corresponding efforts to model operation of the TAMU ZS-1 and GS-2 Terry turbines with Sandia National Laboratories’ (SNL) MELCOR code. The current MELCOR modeling approach represents the Terry turbine with a system of equations expressing the conservation of angular momentum. The joint analysis and experimental program identified that a) it is possible for the Terry turbine to develop the same power at different speeds, and b) turbine losses appear to be insensitive to the size of the turbine. As part of this program, further study of Terry turbine modeling unknowns and uncertainties is planned to support more extensive application of modeling and simulation to the enhancement of plant-specific operational and accident procedures.
Hazard Analysis of Digital Engineered Safety Features Actuation System in Advanced Nuclear Power Plants Using a Redundancy-Guided Approach
Authors: Bao Han , Shorthill Tate , Zhang Hongbin
Published: October 2020

Replacing the existing aging analog instrumentation and control (I&C) systems with modern safety control and protection digital technology offers one of the foremost means of performance improvements and cost reductions for the existing nuclear power plants (NPPs). However, the qualification of digital I&C systems remains a challenge, especially considering the issue of software common-cause failures (CCFs), which are difficult to address. With the application and upgrades of advanced digital I&C systems, software CCFs have become a potential threat to plant safety because most redundant designs use similar digital platforms or software in the operating and application systems. With complex designs of multilayer redundancy to meet the single-failure criterion, digital I&C safety systems (e.g., engineered safety-features actuation system [ESFAS]) are of a particular concern in the U.S. Nuclear Regulatory Commission (NRC) licensing procedures. This paper applies a modularized approach to conduct redundancy-guided systems-theoretic hazard analysis for an advanced digital ESFAS with multilevel redundancy designs. Systematic methods and risk-informed tools are incorporated to address both hardware and software CCFs, which provide guidance to eliminate the triggers of potential single points of failure in the design of digital safety systems in advanced plant designs.
Applicability of Dynamic Modeling for Turbulent Schmidt and Prandtl Numbers on Density Stratification Breakup in Several Flow Conditions
Authors: Abe Satoshi , Studer Etienne , Ishigaki Masahiro , Sibamoto Yasuteru , Yonomoto Taisuke
Published: October 2020

Many experiments on density stratification breakup in several flow conditions have been performed with the large- and small-scale experimental facilities to understand the mechanism underlying hydrogen behavior in a nuclear containment vessel during a severe accident. To improve the predictability of the RANS (Reynolds-averaged Navier Stokes) approach, we implemented the dynamic modeling for turbulent Schmidt Sct and Prandtl Prt numbers. In this paper, the capability of the RANS analysis with dynamic Sct modeling is assessed with several experimental data obtained by using the MISTRA (Commissariat à l’énergie atomique et aux énergies alternatives, CEA, France), CIGMA and VIMES (Japan Atomic Energy Agency, Japan). For the quantitative assessment, the completion time of the stratification breakup, defined as when helium concentration in the upper region decreases to the same value in the lower region, is focused. The comparison study shows the good performance of the dynamic modeling for Sct and Prt. Besides, in the case with the low jet Froude number, the CFD accuracy declines significantly, because the jet upward bending is over-estimated.