bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive behaviour of Chinese boys with fragile X syndrome
Authors: Zhu Z. , Li W. , Zhan J. , Hu L. , Wu L. , Zhao Z.
Published: September 2015

Background

Adaptive behaviour is closely related to quality of life in children with intellectual disability (ID), but little is known about the adaptive behaviour of children with fragile X syndrome (FXS) in China.

Method

In boys with FXS, the adaptive behaviours in six domains, including self‐dependence, locomotion, work skills, communication, socialisation and self‐management, were assessed by the Infants‐Junior Middle School Students Social‐life Abilities Scale. In addition, we compared the adaptive skills of boys with FXS to those of three control groups of boys, including boys with Down syndrome (DS) and typically developing (TD) boys matched by chronological age (CA) or mental age (MA). The profile of the adaptive behaviour of boys with FXS is discussed in detail.

Results

Compared to boys with DS, boys with FXS obtained lower scores in three domains in adaptive behaviour, including work skills, socialisation and self‐management skills; boys with FXS had better scores in self‐dependence and locomotion skills than boys matched for MA; as expected, boys with FXS had significantly poorer adaptive skills in all six domains assessed compared to CA boys.

Conclusion

The development of adaptive skills in boys with FXS was worse than that of boys with DS. The profile of the adaptive behaviour of boys with FXS establishes a basis for the development of targeted interventions to promote social development in this population. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd
Is riluzole a new drug for Alzheimer's disease?
Authors: Whitcomb Daniel J. , Molnár Elek
Published: September 2015

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This Editorial highlights a study by Hunsberger et al. (2015) in the current issue of Journal of Neurochemistry, in which the authors explore the effects of riluzole (R) treatment on tau‐P301L transgenic mice. The authors employed a comprehensive analysis of possible restorative effects of the drug by examining glutamate levels in subregions of the hippocampus, expression of tau and its hyper‐phosphorylated forms, and memory function using behavioral tests. The authors report a simultaneous reduction in glutamate reuptake and an increase in glutamate release in the tau‐P301L model, both of which are ameliorated with riluzole treatment. The authors' findings have implications for our understanding of synaptic transmission mechanisms also associated with Alzheimer's disease pathology.
Reproductive Stage and Modulation of Stress‐Induced Tau Phosphorylation in Female Rats
Authors: Steinmetz Danielle , Ramos Eugenia , Campbell Shannon N. , Morales Teresa , Rissman Robert A.
Published: September 2015

Chronic stress is implicated as a risk factor for Alzheimer's disease (AD) and other neurodegenerative disorders. Although the specific mechanisms linking stress exposure and AD vulnerability have yet to be fully determined, our laboratory and others have shown that acute and repeated restraint stress in rodents leads to an increase in hippocampal tau phosphorylation (tau‐P) and tau insolubility, a critical component of tau pathology in AD. Although tau phosphorylation induced by acute psychological stress is dependent on intact signaling through the type 1 corticotropin‐releasing factor receptor, how sex steroids or other modulators contribute to this effect is unknown. A naturally occurring attenuation of the stress response is observed in female rats at the end of pregnancy and throughout lactation. To test the hypothesis that decreased sensitivity to stress during lactation modulates stress‐induced tau‐P, cohorts of virgin, lactating and weaned female rats were subjected to 30 min of restraint stress or no stress (control) and were killed 20 min or 24 h after the episode. Exposure to restraint stress induced a significant decrease in tau‐P in the hippocampus of lactating rats killed 20 min after stress compared to lactating controls and virgins subjected to stress treatment. Lactating rats killed 24hr after restraint stress exposure showed significant elevation in tau‐P compared to lactating cohorts killed 20 min after stress. Levels of tau‐P in these latter cohorts did not differ signficantly from control animals. Furthermore, glycogen synthase kinase (GSK)3‐α levels were significantly decreased in stressed lactating animals at both timepoints. This suggests a steep, yet transient stress‐induced dephosphorylation of tau, influenced by GSK3, in the hippocampus of lactating rats.
HEDONIC PRICING WHEN HOUSING IS ENDOGENOUS: THE VALUE OF ACCESS TO THE TRANS‐ISRAEL HIGHWAY*
Authors: Beenstock Michael , Feldman Dan , Felsenstein Daniel
Published: September 2015

Standard hedonic house pricing assumes that house prices are independent of the intangible to be priced. A methodology is proposed in which the supply as well as the demand for housing depends on the intangible. The methodology is applied to value access to the Trans‐Israel Highway (TIH). Using spatial panel data (2002–2008) we show that TIH had two effects on the housing market. It increased house prices in locations with greater access to TIH, and it affected housing construction. Standard hedonic pricing would have underestimated the value of access because it ignores the effects of housing construction on the intangible to be priced. House prices began to increase three years before TIH was inaugurated, but housing construction did not anticipate the inauguration of TIH.
Caring stress, suicidal attitude and suicide care ability among family caregivers of suicidal individuals: a path analysis
Authors: Chiang C.‐Y. , Lu C.‐Y. , Lin Y.‐H. , Lin H.‐Y. , Sun F.‐K.
Published: September 2015

Accessible summary

What is known on the subject?

Suicide is a global mental health issue. Taking care of suicidal individuals is a substantial challenge. Most studies emphasize the suicidal individual. Few studies have emphasized the family caregivers of suicidal individuals.

No study has explored the relationship between family caregivers' caring stress with suicidal attitudes and suicide care ability.

What this paper adds to existing knowledge?

The main results indicated that the older family caregivers tended to have a more negative attitude towards suicidal individuals. Female family caregivers' stress was higher than that of male family caregivers.

A mild level of caring stress would help family caregivers have a more positive attitude towards suicidal individuals. Furthermore, a positive attitude would help family caregivers improve their caring ability.

What are the implications for practice?

Mental health nurses could help family caregivers, especially female family caregivers, reduce their holistic caring burden by looking for support resources and enhancing their coping strategies.

Mental health nurses could help family caregivers promote positive attitudes towards suicidal relatives by understanding suicidal individuals' suffering.

Introduction

Suicide is a global mental health issue. Family caregivers play a key role in preventing suicide attempts.

Aims

The aim of this study was to examine the relationship among stress due to the family caregiver's role, suicidal attitude of the family caregiver and suicide care ability among family caregivers. Additionally, instruments of caring stress, attitudes towards suicidal relatives and caring abilities used in the study were tested to measure construct validity.

Methods

A cross‐sectional correlational study was conducted with 164 family caregivers of people who are suicidal. The following three questionnaires were used: the Caring Stress Scale, the Suicidal Attitudes Scale and the Suicidal Caring Ability Scale. Structural equation modelling was performed using SPSS AMOS 19.0 to examine the path relationships among variables.

Results

Bivariate analyses showed that age was negatively correlated with suicidal attitude. In the final path model, caring stress had a positive effect on suicidal attitudes. Suicidal attitude and suicide care ability were highly positively correlated. Gender had a direct effect on caring stress, which indicated that female family caregivers experienced more stress from their role.

Implications for practice:

Mental health nurses could help family caregivers become aware of the emotional pain that suicidal people experience and then promote their positive attitudes towards their suicidal relatives. Furthermore, family caregivers could increase their ability to care for their suicidal relatives, which could reduce the numbers of suicides.
Physiological adaptive indicators in fasted neonate broiler chicks in response to calcium gluconate injection
Authors: Khosravinia H.
Published: September 2015

Four hundred and eighty mixed‐sex broiler chicks aged 3 h after hatching were allotted according to a completely random design in a 6 × 2 × 2 factorial schedule into two groups of 12 replications of 20 chicks each. The main experimental factors were fasting for 0, 6, 12, 24, 36 and 48 h after chick placement and calcium gluconate (Ca‐glu) injection (0 and 0.6 ml). Live body weight (BW) of chicks decreased linearly (Y = 43.36–0.109BW0 h, r2 = 0.876) as neonatal fasting extended. Injection of 0.6 ml Ca‐glu at 3 h post‐hatching did not affect weight loss of chicks. Yolk residuals (YR) utilized linearly (Y = 5.75–0.062YR, r2 = 0.956) by 0.062 g/h in neonate fasted chicks up to 48 h, showing no effect of Ca‐glu injection. Neonatal fasting periods longer than 12 h increased liver weight (p < 0.05). The mean absolute and proportional (% of BW0 h) breast and leg weight were reduced linearly as neonatal fasting extended (p < 0.05). Serum glucose concentration increased up to 6 h and then reduced linearly to 150 mg/dl after 48‐h fasting. The Ca‐glu treatment influenced serum glucose level for a short period up to 6 h of fasting. Serum Ca concentration sharply increased up to threefolds in the birds received Ca‐glu injection resulting in acute hypercalcemia, then decreased to the initial level after 24‐h feed withdrawal (p < 0.05). The mean serum level for creatinine, uric acid, cholesterol, HDL, albumins and total proteins significantly increased during the fasting periods of 6 to 48 h and significantly elevated in the birds receiving 0.6‐ml Ca‐glu injection compared with the non‐treated chicks (p < 0.05). It was concluded that subcutaneous administration of 0.6 ml Ca‐glu in the chick's neck did not suitably support the increased metabolic demands for glucose and calcium in feed‐deprived neonate chicks.
An Empirical Study of Commodity Prices after Sir Arthur Lewis
Authors: Ghoshray Atanu , Perera Ashira
Published: September 2015

This paper builds on the work of Deaton and Laroque (Journal of Development Economics, Vol. 71 (2003), pp. 289–310) by empirically testing for long‐run commodity price adjustment in a non‐linear framework. We propose a non‐linear adjustment mechanism of commodity price dynamics linked to the Lewis model. Using more recent data by updating the price, income and production indices, we employ advanced econometric techniques in order to investigate whether there is empirical evidence to support the arguments of the non‐linear model. The findings lend support to the underlying non‐linear framework proposed in this paper.
Thiamine‐induced priming against root‐knot nematode infection in rice involves lignification and hydrogen peroxide generation
Authors: Huang Wen‐Kun , Ji Hong‐Li , Gheysen Godelieve , Kyndt Tina
Published: September 2015

Thiamine (vitamin B1, VB1) can act as a plant defence trigger, or priming agent, leading to a rapid counterattack on pathogen invasion. In this study, the priming effect of thiamine on rice (Oryza sativa cv. Nipponbare) and its activity against root‐knot nematode (Meloidogyne graminicola) infection were evaluated. Thiamine treatment and subsequent nematode inoculation activated hydrogen peroxide (H2O2) accumulation and lignin deposition in plant roots, and this correlated with enhanced transcription of OsPAL1 and OsC4H, two genes involved in the phenylpropanoid pathway. The number of nematodes in rice roots was slightly but significantly reduced, and the development of the nematodes was delayed, whereas no direct toxic effects of VB1 on nematode viability and infectivity were observed. The combined application of thiamine with l‐2‐aminooxy‐3‐phenylpropionic acid (AOPP), an inhibitor of phenylalanine ammonia‐lyase (PAL), significantly hampered the VB1‐priming capacity. These findings indicate that thiamine‐induced priming in rice involves H2O2 and phenylpropanoid‐mediated lignin production, which hampers nematode infection. Further cellular and molecular studies on the mechanism of thiamine‐induced defence will be useful for the development of novel nematode control strategies.
Dental caries – not just holes in teeth! A perspective
Authors: Bowen W.H.
Published: September 2015

Cavitation in teeth results from a pathogenic process termed dental caries that has occurred on the tooth surface for weeks or even years. Accumulation of dental plaque (biofilm) on the tooth is usually the first manifestation of the disease. Although acid production is the immediate and proximal cause of dissolution of teeth; it is the milieu within which the acid is formed that should be of primary concern. Focusing on the ‘critical pH’ has detracted attention from the more biological aspects (biofilm formation) of dental caries. Dental caries is unique; it is a biological process occurring on essentially an inert surface. Investigation of the multitude of interactions occurring in plaque ranging from enamel interfaces to surfaces of bacteria and matrices poses challenges worthy of the best scientific minds. The mouth clearly offers unique opportunities to investigate the multi facets of biofilm formation in vivo, generating data that have relevance way beyond the mouth. Prevention of this ubiquitous disease, dental caries, continues to present serious challenges. The public health benefits of fluoride delivered in its various formats are well recognized. Nevertheless, additional preventive approaches are required. Overcoming the rapid clearance of agents from the mouth is particularly challenging. Building on the polymerizing capacity of glucosyltransferases it may be possible to incorporate a therapeutic agent into the matrix plaque, thereby delivering therapeutic agents precisely to where they are needed.
Downfall of the current antibody correlates of influenza vaccine response in yearly vaccinated subjects: Toward qualitative rather than quantitative assays
Authors: Cagigi Alberto , Cotugno Nicola , Rinaldi Stefano , Santilli Veronica , Rossi Paolo , Palma Paolo
Published: September 2015

Response to seasonal influenza vaccination is currently evaluated by antibody correlates that estimate vaccine seroconversion as well as immune protection. These correlates rely on the general dogmas surrounding seasonal influenza vaccination; that is, that vaccine‐induced antibodies would exclusively generate immunity to influenza vaccine strains and that protective immunity would wane before the next season. Here, we summarize recently reported data on immunity to seasonal influenza in healthy individuals and rediscuss results on yearly vaccinated pediatric immunocompromised patients that together highlight the need for revision of the current correlates of vaccine response to shift from quantitative to qualitative measurements.
Intralesional Candida Antigen Immunotherapy for the Treatment of Recalcitrant and Multiple Warts in Children
Authors: Muñoz Garza Fania Z. , Roé Crespo Esther , Torres Pradilla Mauricio , Aguilera Peirò Paula , Baltà Cruz Susana , Hernández Ruiz María Eugenia , Baselga Torres Eulàlia
Published: September 2015

Background

Intralesional injection of Candida antigen appears to be an effective alternative for the treatment of warts.

Aim

To determine the efficacy and safety of this treatment.

Methods

We retrospectively reviewed records of all children who received intralesional injection of Candida antigen at our center from January 2008 to July 2013.

Results

From a total of 220 patients, 156 (70.9%) had a complete response, 37 (16.8%) had a partial response, and 27 (12.2%) had no improvement. An average of 2.73 treatments was needed. Forty‐seven of the patients with more than one wart (21.3%) also noted at least partial resolution of untreated warts at distant sites. Twenty‐seven of the 47 patients (57.4%) had complete resolution. All treated patients experienced some discomfort at the time of the injection, but no serious side effects were reported.

Discussion

We report our results using this approach in a large group of children.

Conclusion

Intralesional injection of Candida antigen is an effective and safe therapy for children with multiple and recalcitrant cutaneous warts.
Negative internal causal attributions of a specific offense and forgiveness
Authors: HOOK JOSHUA N. , RAMOS MARCIANA J. , WORTHINGTON EVERETT L. , UTSEY SHAWN O. , COY ANTHONY E. , DAVIS DON E. , VAN TONGEREN DARYL R. , GARTNER AUBREY L. , JENNINGS DAVID J. , DUECK AL
Published: September 2015

Causal attributions are important social‐cognitive predictors of forgiveness. This article presents the Transgression Attribution Questionnaire (TAQ), a measure of one's negative internal causal attributions of a specific offense. In 4 studies, scores on the TAQ showed initial evidence of estimated internal consistency, temporal stability, and construct validity. Negative internal attributions for the cause of a transgression predicted lower levels of empathy and forgiveness. Furthermore, scores on the TAQ predicted forgiveness over and above the hurtfulness of the offense, relationship commitment, and a general measure of internal causal attributions in relationships. The current research bridges research on internal causal attributions and forgiveness. Implications for the social‐cognitive study of forgiveness and the measurement of causal attributions are discussed.
Linking financial distress to marital quality: The intermediary roles of demand/withdraw and spousal gratitude expressions
Authors: BARTON ALLEN W. , FUTRIS TED G. , NIELSEN ROBERT B.
Published: September 2015

This study investigates demand/withdraw communication and spousal expressions of gratitude as intervening variables in the association between financial distress and marital quality. With a sample of 468 married individuals, dual‐mediation models revealed demand/withdraw transmitted the effect of financial distress onto 3 different marital outcomes; in most instances, this indirect effect occurred through total couple demand/withdraw and not one spouse‐specific pattern. In moderated mediation models, spousal gratitude exerted main effects on all marital outcomes and, for a subset of outcomes, protective effects for couples with high levels of demand/withdraw. Results elucidate how demand/withdraw patterns link financial distress to marital outcomes and highlight spousal gratitude expressions as a promising, yet understudied, process within couples that promotes and protects marital quality.
Whose personality is better, mine or my partner's? Self‐enhancement bias in relationships
Authors: EL‐ALAYLI AMANI , WYNNE MELODI
Published: September 2015

Previous research has documented self‐enhancement and relationship partner‐enhancement motivations, but not examined whether individuals view themselves or their partners more favorably, overall. The authors conducted three studies that revealed a general tendency to favor oneself over one's partner in direct self–partner personality comparisons. This illustrated a motivational precedence of self‐enhancement over partner‐enhancement goals. In Study 1, participants rated self‐only traits more favorably than partner‐only traits. In Studies 2 and 3, participants rated desirable traits as more characteristic of themselves than their partner, particularly when traits were more relevant to personal than relationship success. The authors also found that this self‐favoring bias was weaker (typically nonexistent) among those with higher relationship satisfaction, lower self‐esteem, or lower self‐deceptive tendencies. The authors discuss practical, theoretical, and methodological implications.
No Exception for Belief
Authors: Rinard Susanna
Published: September 2015

This paper defends a principle I call Equal Treatment, according to which the rationality of a belief is determined in precisely the same way as the rationality of any other state. For example, if wearing a raincoat is rational just in case doing so maximizes expected value, then believing some proposition P is rational just in case doing so maximizes expected value. This contrasts with the popular view that the rationality of belief is determined by evidential support. It also contrasts with the common idea that in the case of belief, there are two different incommensurable senses of rationality, one of which is distinctively epistemic. I present considerations that favor Equal Treatment over these two alternatives, reply to objections, and criticize some arguments for Evidentialism. I also show how Equal Treatment opens the door to a distinctive kind of response to skepticism.
Induction of the viable but nonculturable state in Clavibacter michiganensis subsp. michiganensis and in planta resuscitation of the cells on tomato seedlings
Authors: Jiang N. , Lv Q. Y. , Xu X. , Cao Y. S. , Walcott R. R. , Li J. Q. , Luo L. X.
Published: September 2015

Bacterial canker of tomato is an economically important seedborne disease caused by Clavibacter michiganensis subsp. michiganensis (Cmm). Copper‐based bactericides and seed treatment with hydrochloric acid are commonly used for bacterial canker management. Recent studies have shown that some bacteria can enter a viable but nonculturable (VBNC) state, and fail to form colonies on microbiological agar media. Bacteria in the VBNC state can recover their culturability when returned to favourable conditions. This study reports the induction of the VBNC state in Cmm by CuSO4 and low pH, and resuscitation of VBNC cells on tomato seedlings. Flow cytometry using the nucleic acid dyes SYTO 9 and propidium iodide, combined with agar plating, was used to assess VBNC cell counts. It was demonstrated that CuSO4 and low pH induced the VBNC state in Cmm and the rate of induction increased with copper ion concentration and acidity. Pathogenicity tests showed that some of the VBNC cells induced by CuSO4 retained their ability to colonize tomato seedlings but failed to produce typical bacterial canker symptoms by 2 months post‐inoculation. This was probably due to low levels of resuscitation of VBNC Cmm cells resulting in low levels of initial inoculum. This study has improved understanding of the VBNC state of Gram‐positive phytopathogenic bacteria. Most importantly, because copper‐based chemicals and low pH conditions are used for disease management, induction of the VBNC state and subsequent resuscitation of Cmm cells on tomato seedlings may limit pathogen detection by culture‐based assays yet present a risk for disease development in the field.
Somatosensory mu activity reflects imagined pain intensity of others
Authors: Hoenen Matthias , Lübke Katrin T. , Pause Bettina M.
Published: September 2015

In accordance with simulation theories of empathy, the somatosensory cortex is involved in the perception of pain of others. Cognitive processes, like perspective taking, can alter empathy‐related activity within the somatosensory cortex. The current study investigates whether this modulation is caused by the imagined sensation of pain or by the cognitive load of a perspective‐taking task. Applying a within‐subject design, participants (N = 30) watched pictures of painful and nonpainful actions, while imagining reduced, normal, or increased pain perception of the observed individual. Mu activity (8–13 Hz), which is inversely correlated with sensorimotor‐cortex activity, was measured via EEG. To calculate mu activity (central electrodes) and alpha activity (occipital electrodes), which served as a control for effects of cognitive load, a fast Fourier transform was applied. Mu suppression linearly increased from reduced to normal to increased imagined pain (p < .05), while alpha activity was unaffected by the imagined pain (p > .80). Suppression of the 8–13 Hz band at central and occipital electrodes was stronger in response to painful actions compared to nonpainful actions (p < .01). These results indicate that modulation of mu activity through perspective taking reflects the imagined pain intensity and not the cognitive load induced by the task.
Beyond (and Within) City Limits: Climate Policy in an Intergovernmental System
Authors: Simon Rosenthal Cindy , Rosenthal James A. , Moore Jonathan D. , Smith Jamie
Published: September 2015

This analysis explores the role of city‐level and state‐level variables to explain why some cities make more progress on climate‐related policy implementation than others. Using multilevel modeling, we find little support for the influence of state factors on local government leadership among the 812 cities in the dataset, but local government institutional and community variables are strongly associated with climate policy initiatives. We argue for a rethinking of the notion of the limited and constrained city and suggest that, in the realm of climate protection and environmental policy, cities are leading a bottom‐up federalism. Moreover, where some political analysts and scholars have argued that climate protection and environmental policies may not be economically rational for cities to pursue, we theorize that cities are acting locally to further their self‐interest in an increasingly global economy.
Globalization, International Organizations, and Telecommunications
Authors: Rodine‐Hardy Kirsten
Published: September 2015

Since the 1990s over 158 countries established pro‐market reforms in telecommunications—a fast pace for such a drastic change. For example, Sweden and Botswana, two nations vastly different across multiple dimensions, both liberalized their telecom sectors. Why did so many countries adopt liberal reforms in such a short period of time? Conventional wisdom highlights the role of global markets and technology, powerful states, global diffusion, and domestic politics. I argue that contrary to these claims, diffusion through key international organizations is the critical and overlooked factor in explaining rapid global convergence of pro‐market telecom reforms. Using an original dataset for 189 countries between 1970 and 2003 and event history analysis, I demonstrate that membership in key liberal trading organizations, especially the WTO and the OECD, increases the likelihood that countries will adopt liberal pro‐market reforms in telecommunications. These results speak directly to current public policy debates about the reregulation of global markets and bridges the literatures of policy diffusion, institutional design, and regulatory regimes.
Economic drivers of contemporary smallholder agriculture in a transitional economy: A case study of Hu Village from southwest China
Authors: Hu Zhanping , Rahman Sanzidur
Published: September 2015

Based on an in‐depth case study of a rural community, this paper documents the contemporary state of Chinese smallholder agriculture and the changes that it has been experiencing in the context of dramatic socio‐economic transition through the lens of three main economic drivers: livelihood diversification, market conditions and government interventions. Results reveal that the change in Chinese smallholder agriculture has been complex and multidimensional. All three factors exert profound influence and shape the current state of Chinese agriculture. Massive rural‐urban migration has resulted in labour shortages, which in turn have led to a reduction in agricultural diversity and land use intensity and a shift from traditional labour‐intensive technologies to modern capital‐intensive technologies. However, because of well‐developed agricultural markets, input use levels are similar across farmer categories (such as income diversification), helping to maintain productivity. Furthermore, reduced profits from farming due to increasing input prices and decreasing output prices have exerted pressure on smallholders to increasingly turn to nonfarm activities and have also triggered a thriving informal land transfer market, which was previously non‐existent. Policy implications include the need to strengthen local economies, improve market conditions, invest in rural infrastructures and facilitate smallholders' mobility.
Exploring Cognitive Diversity: Anthropological Perspectives on Cognition
Authors: Beller Sieghard , Bender Andrea
Published: September 2015

Anthropology and the other cognitive sciences currently maintain a troubled relationship (Beller, Bender, & Medin, ). What could rapprochement look like, and how could it be achieved? The seven main articles of this topic present anthropological or anthropologically inspired cross‐cultural research on a diverse set of cognitive domains. They serve as an existence proof that not only do synergies abound across anthropology and the other cognitive sciences, but that they are worth achieving.
Fetal and neonatal alloimmune thrombocytopenia: predictive factors of intracranial hemorrhage
Authors: Delbos Florent , Bertrand Gérald , Croisille Laure , Ansart‐Pirenne Hélène , Bierling Philippe , Kaplan Cécile
Published: September 2015

BACKGROUND

In Caucasians, fetal/neonatal alloimmune thrombocytopenia (FNAIT) is most frequently caused by maternal alloimmunization against the human platelet antigen HPA‐1a. The most serious complication of severe FNAIT is intracranial hemorrhage (ICH). ICH mainly occurs in utero; therefore, there is a need to identify noninvasive predictive factors of ICH to facilitate early identification of this condition and to determine response to maternal therapy.

STUDY DESIGN AND METHODS

We studied gynecologic and immunogenetic variables of severe cases of anti‐HPA‐1a FNAIT within three groups: Group I, FNAIT without ICH; Group II, FNAIT with ICH; and Group III, suspected FNAIT cases without detectable maternal anti‐HPA‐1a alloantibodies.

RESULTS

ICH was associated with a poor outcome because it led to death in 59% of cases. Multigravida (two or more pregnancies) was overrepresented in Group II, consistent with the high concentrations of maternal HPA‐1a alloantibody and the frequent detection of a strong newborn‐specific HLA class I antibody response at delivery. The proportion of HLA‐DRB4*01:01P (*01:01 or *01:03) women was similar in Groups I and II, but this allele was overrepresented in Group III, in which FNAIT was less severe than in the other two groups. Finally, antenatal intravenous immunoglobulin therapy tended to be more effective in HLA‐DRB3*01:01(+)/HLA‐DRB4*01:01P(+) women than for HLA‐DRB3*01:01(+)/HLA‐DRB4*01:01P(–) women.

CONCLUSION

The number of gestations is a predictive factor of ICH in anti‐HPA‐1a–alloimmunized women. Maternal immunogenetic variables should be investigated in the context of maternal immunization and may predict response to maternal therapy in subsequent pregnancies.
In a canine pneumonia model of exchange transfusion, altering the age but not the volume of older red blood cells markedly alters outcome
Authors: Cortés‐Puch Irene , Remy Kenneth E. , Solomon Steven B. , Sun Junfeng , Wang Dong , Al‐Hamad Mariam , Kelly Seth M. , Sinchar Derek , Bellavia Landon , Kanias Tamir , Popovsky Mark A. , Kim‐Shapiro Daniel B. , Klein Harvey G. , Natanson Charles
Published: September 2015

BACKGROUND

Massive exchange transfusion of 42‐day‐old red blood cells (RBCs) in a canine model of Staphylococcus aureus pneumonia resulted in in vivo hemolysis with increases in cell‐free hemoglobin (CFH), transferrin‐bound iron (TBI), non–transferrin‐bound iron (NTBI), and mortality. We have previously shown that washing 42‐day‐old RBCs before transfusion significantly decreased NTBI levels and mortality, but washing 7‐day‐old RBCs increased mortality and CFH levels. We now report the results of altering volume, washing, and age of RBCs.

STUDY DESIGN AND METHODS

Two‐year‐old purpose‐bred infected beagles were transfused with increasing volumes (5‐10, 20‐40, or 60‐80 mL/kg) of either 42‐ or 7‐day‐old RBCs (n = 36) or 80 mL/kg of either unwashed or washed RBCs with increasing storage age (14, 21, 28, or 35 days; n = 40).

RESULTS

All volumes transfused (5‐80 mL/kg) of 42‐day‐old RBCs resulted in alike (i.e., not significantly different) increases in TBI during transfusion as well as in CFH, lung injury, and mortality rates after transfusion. Transfusion of 80 mL/kg RBCs stored for 14, 21, 28, and 35 days resulted in increased CFH and NTBI in between levels found at 7 and 42 days of storage. However, washing RBCs of intermediate ages (14‐35 days) does not alter NTBI and CFH levels or mortality rates.

CONCLUSIONS

Preclinical data suggest that any volume of 42‐day‐old blood potentially increases risks during established infection. In contrast, even massive volumes of 7‐day‐old blood result in minimal CFH and NTBI levels and risks. In contrast to the extremes of storage, washing blood stored for intermediate ages does not alter risks of transfusion or NTBI and CFH clearance.
Numerical Study of Cerebroarterial Hemodynamic Changes Following Carotid Artery Operation: A Comparison Between Multiscale Modeling and Stand-Alone Three-Dimensional Modeling
Authors: Liang Fuyou , Oshima Marie , Huang Huaxiong , Liu Hao , Takagi Shu
Published: September 2015

Free outflow boundary conditions have been widely adopted in hemodynamic model studies, they, however, intrinsically lack the ability to account for the regulatory mechanisms of systemic hemodynamics and hence carry a risk of producing incorrect results when applied to vascular segments with multiple outlets. In the present study, we developed a multiscale model capable of incorporating global cardiovascular properties into the simulation of blood flows in local vascular segments. The multiscale model was constructed by coupling a three-dimensional (3D) model of local arterial segments with a zero-one-dimensional (0-1-D) model of the cardiovascular system. Numerical validation based on an idealized model demonstrated the ability of the multiscale model to preserve reasonable pressure/flow wave transmission among different models. The multiscale model was further calibrated with clinical data to simulate cerebroarterial hemodynamics in a patient undergoing carotid artery operation. The results showed pronounced hemodynamic changes in the cerebral circulation following the operation. Additional numerical experiments revealed that a stand-alone 3D model with free outflow conditions failed to reproduce the results obtained by the multiscale model. These results demonstrated the potential advantage of multiscale modeling over single-scale modeling in patient-specific hemodynamic studies. Due to the fact that the present study was limited to a single patient, studies on more patients would be required to further confirm the findings.
Assessment of Candidate Fuel Cladding Alloys for the Canadian Supercritical Water-Cooled Reactor Concept
Authors: Guzonas D. , Edwards M. , Zheng W.
Published: September 2015

Selecting and qualifying a fuel cladding material for the Canadian supercritical water-cooled reactor (SCWR) concept remains the most significant materials challenge to be overcome. The peak cladding temperature in the Canadian SCWR concept is predicted to be as high as 800°C. While advanced materials show promise for future deployment, currently, the best options available are austenitic stainless steels and nickel-based alloys. Many of these alloys were extensively studied for use as fuel cladding materials in the 1960s, as part of programs to develop nuclear superheated steam reactors. After extensive out-of-pile testing and consideration of the existing data, five alloys (347 SS, 310 SS, Alloy 800H, Alloy 625, and Alloy 214) were selected for more detailed assessment using a combination of literature surveys and targeted testing to fill in major knowledge gaps. Wherever possible, performance criteria were developed for key materials properties. This paper summarizes the methodology used for the assessment and presents the key results, which show that 310 SS, Alloy 800H, and Alloy 625 would all be expected to give acceptable performance in the Canadian SCWR concept.
Three-Dimensional LEFM Prediction of Fatigue Crack Propagation in a Gas Turbine Disk Material at Component Near Conditions
Authors: Busse Christian , Gustafsson David , Rasmusson Patrik , Sjödin Björn , Moverare Johan J. , Simonsson Kjell , Leidermark Daniel
Published: September 2015

In this paper, the possibility to use linear elastic fracture mechanics (LEFM), with and without a superimposed residual stress field, to predict fatigue crack propagation in the gas turbine disk material Inconel 718 has been studied. A temperature of 400 °C and applied strain ranges corresponding to component near conditions have been considered. A three-dimensional crack propagation software was used for determining the stress intensity factors (SIFs) along the crack path. In the first approach, a linear elastic material behavior was used when analyzing the material response. The second approach extracts the residual stresses from an uncracked model with perfectly plastic material behavior after one loading cycle. As a benchmark, the investigated methods are compared to experimental tests, where the cyclic lifetimes were calculated by an integration of Paris' law. When comparing the results, it can be concluded that the investigated approaches give good results, at least for longer cracks, even though plastic flow was taking place in the specimen. The pure linear elastic simulation overestimates the crack growth for all crack lengths and gives conservative results over all considered crack lengths. Noteworthy with this work is that the 3D-crack propagation could be predicted with the two considered methods in an LEFM context, although plastic flow was present in the specimens during the experiments.
Transient Analysis of Gas-Expanded Lubrication and Rotordynamic Performance in a Centrifugal Compressor
Authors: Weaver Brian K. , Kaplan Jason A. , Clarens Andres F. , Untaroiu Alexandrina
Published: September 2015

Gas-expanded lubricants (GELs) have the potential to increase bearing energy efficiency, long-term reliability, and provide for a degree of control over the rotordynamics of high-speed rotating machines. Previous work has shown that these tunable mixtures of synthetic oil and dissolved carbon dioxide could be used to maximize the stability margin of a machine during startup by controlling bearing stiffness and damping. This allows the user to then modify the fluid properties after reaching a steady operating speed to minimize bearing power loss and reduce operating temperatures. However, it is unknown how a typical machine would respond to rapid changes in bearing stiffness and damping due to changes in the fluid properties once the machine has completed startup. In this work, the time-transient behavior of a high-speed compressor was evaluated numerically to examine the effects of rapidly changing bearing dynamics on rotordynamic performance. Two cases were evaluated for an eight-stage centrifugal compressor: an assessment under stable operating conditions as well as a study of the instability threshold. These case studies presented two contrasting sets of transient operating conditions to evaluate, the first being critical to the viability of using GELs in high-speed rotating machinery. The fluid transitions studied for machine performance were between that of a polyol ester (POE) synthetic lubricant and a GEL with a 20% carbon dioxide content. The performance simulations were carried out using a steady-state thermoelastohydrodynamic (TEHD) bearing model, which provided bearing stiffness and damping coefficients as inputs to a time-transient rotordynamic model using Timoshenko beam finite elements. The displacements and velocities of each node were solved for using a fourth-order Runge–Kutta method and provided information on the response of the rotating machine due to rapid changes in bearing stiffness and damping coefficients. These changes were assumed to be rapid due to (1) the short lubricant residence times calculated for the bearings and (2) rapid mixing due to high shear rates in the machine bearings causing sudden changes in the fluid properties. This operating condition was also considered to be a worst-case scenario as an abrupt change in the bearing dynamics would likely solicit a more extreme rotordynamic response than a more gradual change, making this analysis quite important. The results of this study provide critical insight into the nature of operating a rotating machine and controlling its behavior using GELs, which will be vital to the implementation of this technology.
Experimental Results and Computational Fluid Dynamics Simulations of Labyrinth and Pocket Damper Seals for Wet Gas Compression
Authors: Vannini Giuseppe , Bertoneri Matteo , Nielsen Kenny Krogh , Iudiciani Piero , Stronach Robert
Published: September 2015

The most recent development in centrifugal compressor technology is toward wet gas operating conditions. This means the centrifugal compressor has to manage a liquid phase which is varying between 0% and 3% liquid volume fraction (LVF) according to the most widely agreed definition. The centrifugal compressor operation is challenged by the liquid presence with respect to all the main aspects (e.g., thermodynamics, material selection, thrust load) and especially from a rotordynamic viewpoint. The main test results of a centrifugal compressor tested in a special wet gas loop (Bertoneri et al., 2014, “Development of Test Stand for Measuring Aerodynamic, Erosion, and Rotordynamic Performance of a Centrifugal Compressor Under Wet Gas Conditions,” ASME Paper No. GT2014-25349) show that wet gas compression (without an upstream separation) is a viable technology. In wet gas conditions, the rotordynamic behavior could be impacted by the liquid presence both from a critical speed viewpoint and stability-wise. Moreover, the major rotordynamic results from the previously mentioned test campaign (Vannini et al., 2014, “Centrifugal Compressor Rotordynamics in Wet Gas Conditions,” 43rd Turbomachinery Symposium, Houston) show that both vibrations when crossing the rotor first critical speed and stability (tested through a magnetic exciter) are not critically affected by the liquid phase. Additionally, it was found that the liquid may affect the vibration behavior by partially flooding the internal annular seals and causing a sort of forced excitation phenomenon. In order to better understand the wet gas test outcomes, the authors performed an extensive computational fluid dynamics (CFD) analysis simulating all the different types of balance piston annular seals used (namely, a tooth on stator (TOS) labyrinth seal and a pocket damper seal (PDS)). They were simulated in both steady-state and transient conditions and finally compared in terms of liquid management capability. CFD simulation after a proper tuning (especially in terms of LVF level) showed interesting results which are mostly consistent with the experimental outcome. The results also provide a physical explanation of the behavior of both seals, which was observed during testing.
Numerical Heat Transfer Analysis of a 50 kWth Pressurized-Air Solar Receiver
Authors: Poživil Peter , Ackermann Simon , Steinfeld Aldo
Published: September 2015

A high-temperature pressurized-air solar receiver, designed for driving a Brayton cycle, consists of a cylindrical SiC cavity and a concentric annular reticulated porous ceramic (RPC) foam enclosed by a steel pressure vessel. Concentrated solar energy is absorbed by the cavity and transferred to the pressurized air flowing across the RPC by combined conduction, convection, and radiation. The governing mass, momentum, and energy conservation equations are numerically solved by coupled Monte Carlo (MC) and finite volume (FV) techniques. Model validation was accomplished with experimental data obtained with a 50 kWth modular solar receiver prototype. The model is applied to elucidate the major heat loss mechanisms and to study the impact on the solar receiver performance caused by changes in process conditions, material properties, and geometry. For an outlet air temperature range 700–1000 °C and pressure range 4–15 bar, the thermal efficiency—defined as the ratio of the enthalpy change of the air flow divided by the solar radiative power input through the aperture—exceeds 63% and can be further improved via geometry optimization. Reradiation is the dominant heat loss.
Application of a Wall-Solar Chimney for Passive Ventilation of Dwellings
Authors: Park David , Battaglia Francine
Published: September 2015

The solar chimney is a natural ventilation technique that has the potential to save energy use in buildings as well as maintain comfortable indoor quality. The objective of the current study was to examine the effects of the wall-solar chimney on airflow distribution and thermal conditions in a room. In the current work, computational fluid dynamics (CFD) was used to model a solar chimney. The solar chimney was modeled three-dimensionally for a more realistic simulation of fluid and thermal conditions. Experimental and numerical data from literature were used to validate the current model, and the results agreed very well. The current study showed that the flow in the solar chimney system can be either laminar or turbulent depending on the parameters of the system, and that the effect of the chimney inlet was more significant than that of the chimney width (air gap between the glass and absorber) on the flow regime. This study also developed a new characteristic Rayleigh number (Ra*) relating the chimney inlet and width, which showed good consistency with the prediction of the flow regime. The investigations of Ra* and the flow regime indicated that the flow becomes turbulent for Ra* ∼ 0.8 × 108. Finally, the potential improvements of the designs were discussed by observing the flow and thermal conditions of the room.