bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Mg Substitution on Order/disorder Transition, Microstructure, and Microwave Dielectric Characteristics of Ba((Co0.6Zn0.4)1/3Nb2/3)O3 Complex Perovskite Ceramics
Authors: Ma Pian Pian , Yi Lei , Liu Xiao Qiang , Li Lei , Chen Xiang Ming
Published: April 2013

Effects of Mg substitution on order/disorder transition, microstructure, and microwave dielectric characteristics of Ba((Co0.6Zn0.4)1/3Nb2/3)O3 complex perovskite ceramics have been investigated. The ordered complex perovskite solid solutions are obtained in Ba((Co0.6−x/2Zn0.4−x/2Mgx)1/3Nb2/3)O3 ceramics (x = 0, 0.1, 0.2, and 0.3), and the ordering degree in the as‐sintered dense ceramics increases with increasing Mg‐substitution amount. The significantly improved Qf value is obtained in the present ceramics with increasing x, whereas the dielectric constant decreases slightly together with some increase of temperature coefficient of resonant frequency. The best combination of microwave dielectric characteristics is obtained in the composition of x = 0.3: εr = 33.7, Qf = 93 800 GHz, and τf = 9.6 ppm/°C. In the Mg‐substituted compositions, clear domain boundaries are obtained and the domain size increases as x increases, the highest Qf value is obtained when the domain size is about 40–60 nm in the ceramics with x = 0.3. The increased ordering degree and the fine ordering domain structure are considered to primarily contribute to the significant increase of Qf value in the Mg‐substituted Ba((Co0.6Zn0.4)1/3Nb2/3)O3 complex perovskite ceramics.
Silicon Carbide Oxidation in High‐Pressure Steam
Authors: Cheng Ting , Tortorelli Peter F.
Published: April 2013

Silicon carbide is a candidate cladding for fission power reactors that can potentially provide better accident tolerance than zirconium alloys. SiC has also been discussed as a host matrix for nuclear fuel. Chemical vapor–deposited silicon carbide specimens were exposed in 0.34–2.07 MPa steam at low gas velocity (~50 cm/min) and temperatures from 1000°C to 1300°C for 2–48 h. As previously observed at lower steam pressure of 0.15 MPa, a two‐layer SiO2 scale was formed during exposure to these conditions, composed of a porous cristobalite layer above a thin, dense amorphous SiO2 surface layer. Growth of both layers depends on temperature, time, and steam pressure. A quantitative kinetics model is presented to describe the SiO2 scale growth, whereby the amorphous layer is formed through a diffusion process and linearly consumed by an amorphous to crystalline phase transition process. Paralinear kinetics of SiC recession were observed after exposure in 0.34 MPa steam at 1200°C within 48 h. High‐pressure steam environments are seen to form very thick (10–100 μm) cristobalite SiO2 layers on CVD SiC even after relatively short‐term exposures (several hours). The crystalline SiO2 layer and SiC recession rate significantly depend on steam pressure. Another model is presented to describe the SiC recession rate in terms of steam pressure when a linear phase transition kl governing the recession kinetics, whereby the reciprocal of recession rate is found to follow a negative unity steam pressure power law.
The Thermal Shock Resistance Analysis of Ceramic Foams
Authors: Zhang Y. X. , Wang B. L. , Li J. E.
Published: April 2013

This article studies the thermal shock resistance behavior of ceramic foams under sudden thermal load induced by a sudden temperature variation. Two types of thermal shock loading conditions are considered: cold shock and hot shock. Variations of the stress and stress intensity factor with thermal shock time, location, crack size, medium thickness, and relative density of the ceramic foam are given. Crack growth behavior is studied and crack growth velocity is explained from energy equilibrium consideration. The thermal shock resistances of ceramic foams are established from the view points of energy criterion and fracture mechanics concept.
Identification of Substitution Mechanism in Group VIII Metal Oxides Doped Pb(Zn1/3Nb2/3)O3–PbZrO3–PbTiO3 Ceramics with High Energy Density and Mechanical Performance
Authors: Zheng Mupeng , Hou Yudong , Wang Sai , Duan Chenghui , Zhu Mankang , Yan Hui
Published: April 2013

Group VIII metal oxides, that is, Fe2O3, Co2O3, and NiO have been introduced to 0.2Pb(Zn1/3Nb2/3)O3–0.8Pb(Zr0.50Ti0.50)O3 (PZN–PZT) to deterministically identify the substitution mechanism and meantime to tailor mechanical and piezoelectric properties in obtaining energy harvesting materials. On the basis of the X‐ray diffraction and Raman analysis, it is clear that the group VIII metal oxides induce a phase transformation from the morphotropic phase boundary to the tetragonal phase side, and the corresponding grain size increases accordingly. It is reasonable to deduce that two types of substitution behaviors coexist in the group VIII metal oxides added PZN–PZT system. Due to the mixed valence of +2 and +3, the foreign doping ions prefer to enter the B site in the perovskite structure, not only substituting for Ti4+, Zr4+, and Nb5+ ions in the inequivalence replacement but also substituting for Zn2+ ions in the equivalence replacement. The proposed complex substitution mechanisms can give the full explanation about the grain growth phenomena and the variation in mechanical and electric properties in the modified PZN–PZT system. At the same doping level of 0.3 mol%, the maximum transduction coefficient (d33·g33 = 13120 × 10−15 m2/N) and good fracture toughness (KIC = 1.32 MPa m1/2) are obtained in Co2O3 added 0.2PZN–0.8PZT ceramics, which shows great promise as practical materials for energy harvesting device applications.
Pressureless Sintering of Hafnium Carbide–Silicon Carbide Ceramics
Authors: Liu Ji‐Xuan , Huang Xiao , Zhang Guo‐Jun
Published: April 2013

HfC‐30 vol%SiC ceramics with a relative density of 99.7% was obtained by pressureless sintering at 2300°C for 0.5 h. The resultant ceramics showed fine microstructure with HfC grain size around 1 μm. The hardness (20.5 ± 0.2 GPa), bending strength (396 ± 56 MPa), and fracture toughness (2.81 ± 0.18 MPa·m1/2) of HfC‐30 vol%SiC ceramics were at least 20% higher than those of monolithic HfC ceramics. The influences of SiC particle size, volume fraction, and the oxide impurity on the microstructure evolution of HfC‐based ceramics were examined. The results indicate that SiC addition and the oxygen impurity introduced by ball milling play opposite roles in the HfC grain growth during sintering. The oxide impurity introduced by ball milling caused the HfC grain coarsening, whereas SiC particles inhibited the grain growth of HfC significantly.
Characterization of Elastic Properties in Porous Silicon Carbide Preforms Fabricated Using Polymer Waxes as Pore Formers
Authors: Roy Siddhartha , Schell Karl Günter , Bucharsky Ethel Claudia , Weidenmann Kay André , Wanner Alexander , Hoffmann Michael J.
Published: April 2013

Thorough elastic analysis of porous silicon carbide preforms fabricated using two different polymer waxes as pore formers is carried out. Both the amount and the mixture ratio of the waxes were varied to fabricate preforms with different pore morphologies and porosities in the range of 27–67 vol%. Results show that both the longitudinal and the shear elastic constants decrease with increasing porosity. The rate of decrease in the elastic constants follows a model based on minimum solid area up to an intermediate porosity level. Uniaxial pressure applied prior to cold isostatic pressing and sintering significantly reduces the stiffness along the press direction. For the same initial powder mixture type, the elastic anisotropy of the preforms increases with an increase in the applied uniaxial pressure. The extent of anisotropy is strongly dependent on both the SiC/wax ratio as well as the mixture ratio between the two wax types. At low pore volume fractions a higher volume content of the smaller diameter wax and at high pore volume fractions a higher volume content of larger diameter wax lead to preforms with lowest anisotropy. A map is finally proposed to describe the dependence of the preform elastic properties on the type of initial powder mixture used.
Fabrication and Characterization of Nanoscale Ferroelectric Honeycombs
Authors: Kim Bongsoo , Hong Seungbum , Choi Hyunwoo , Ryu Won‐Hee , Paik Haemin , Choi Yoon‐Young , Kwon Hyuk‐Sang , No Kwangsoo
Published: April 2013

Nanoscale ferroelectric honeycombs, comprised of vertically aligned PbTiO3 nanotubes, are fabricated by vapor phase reaction between lead acetate‐infiltrated TiO2 nanotubes and PbO vapor. PbTiO3 nanohoneycombs converted by vapor phase reaction at 550°C showed well‐aligned nanoscale structure with alignment angle less than 1° and well‐defined ferroelectric properties with the effective piezoelectric coefficient of 44 pm/V. This novel nanoscale structure is expected to facilitate high efficiency sensing of electromechanical and electrochemical stimuli.
Effects of Solids Loading on Sintering and Properties of Freeze‐Cast Kaolinite–Silica Porous Composites
Authors: Li Wenle , Lu Kathy , Walz John Y.
Published: April 2013

Kaolinite–silica nanocomposites with a green porosity ranging from 75% to 87% were prepared using a freeze‐casting technique. The initial solids loading values (kaolinite platelets plus silica nanospheres) greatly influence the sintering behavior as well as the phase and strength of the resulting porous composites. The composites with lower solids loading exhibit faster sintering (e.g., larger shrinkage, more extensive thickening of the pore walls) when sintered at 1250°C, which in turn, results in a rapid increase in flexural strength. All the composites maintain a high porosity (above 50%) after sintering at 1250°C for 72 h, whereas the flexural strength of the composites increases from roughly 0.2 MPa for the green samples to 13.3, 7.5, and 6.5 MPa for 12, 18, and 24 vol% solids samples, respectively, after sintering. It is believed that solids loading affects kaolinite–silica packing during the sol‐to‐gel transition as a minimum amount of silica nanoparticles is required to build the gel network. This particle packing difference influences the amount of kaolinite–silica interfacial contact, which in turn affects the strength. The strength increase through solids loading change is a combined effect of changes in the porous structure during sintering plus the development of a new phase at the silica–kaolinite interface.
Effect of Substrate on Structure and Multiferrocity of (La,Mn) CoSubstituted BiFeO3 Thin Films
Authors: Wang D. Y. , Ding R. , Li S.
Published: April 2013

In this article, we report the substrate effect on ferroelectric and magnetic properties of epitaxial BiFeO3‐based thin films at room temperature. (La, Mn) cosubstituted BiFeO3 (BFOLM) thin films were deposited on differently lattice mismatched single‐crystal substrates to manipulate the strain states in the as‐deposited films. All the films with 30‐nm thick CaRuO3 bottom electrodes exhibited highly epitaxial growth behavior with a slightly monoclinic distorted lattice structure while their strain states are drastically different as confirmed by X‐ray reciprocal space mapping. These films possessed significantly different macroscopic ferroelectric properties with giant remanent polarization of 101 ± 2, 65 ± 2, and 48 ± 2 μC/cm2 for the films grown on SrTiO3, (La, Sr)(Al, Ta)O3, and LaAlO3, respectively. It is found that the room‐temperature magnetic properties are also in accordance with their strain state, having a reciprocal relationship with polarization. For example, the enhanced magnetization is associated with the suppressed polarization and vice versa. The stain tunability of multiferroic properties in BFOLM thin films are presumably ascribed to the polarization rotation and oxygen octahedral tilts.
Ethical sensitivity in practice: finding tacit moral knowing
Authors: Van Der Zande Marlies , Baart Andries , Vosman Frans
Published: April 2013

Aim

This article presents a discussion of the conceptual model of ethical sensitivity.

Background

Recent research pays little attention to the tacit dimension of ethical knowledge. We focus on care practices, drawing a distinction between explicit moral knowledge and tacit moral knowing. This focus has far‐reaching methodological consequences, influences the research design of empirical research and enables healthcare workers to discern both explicit and tacit knowing.

Data sources

This article draws on literature about tacit knowledge, practices and ethical sensitivity, covering publications from 1958–2011. Data used in the illustrative cases were gathered in 2009 during the phenomenological phase of a multiple‐case study.

Discussion

Taking practices as the point of entry for exploring ethical sensitivity makes it possible to study empirically both explicit moral knowledge and tacit moral knowing. Given how relevant practical knowledge is, we aim to put forward a theoretical framework that leaves room for the discernment of this tacit moral knowing.

Implications for nursing

Creating opportunities to reflect on daily ethical concerns in an inter‐professional team can contribute to improvement on quality of care.

Conclusion

The broadened perspective on ethical sensitivity can be used as a heuristic device to discern what both explicit and implicit moral knowledge in care are about. This empirical way of looking at care practices can enhance the awareness of the moral knowing of the professional caregiver.
Family caregiver strategies to encourage older relatives with dementia to use social services
Authors: Takai Yukari , Yamamoto‐Mitani Noriko , Okamoto Yuko , Fukahori Hiroki , Ko Ayako , Tanaka Makoto
Published: April 2013

Aim

To elicit the strategies used by Japanese family caregivers in the community to encourage older relatives with dementia to use adult daycare and respite stays.

Background

Older adults with dementia often require adult daycare and respite stays for their family caregivers to gain respite from care‐giving. However, persons with dementia often face difficulty in new environments and timely access to sufficient services may be difficult to achieve. Few studies have examined how family caregivers encourage their service use.

Design

A qualitative method.

Methods

Semi‐structured interviews were conducted with 16 family caregivers who were caring for relatives with dementia at home between 2005–2007. Data were analysed qualitatively.

Results

Family caregivers used various strategies to encourage older relatives to use services, allowing the older adult to decide whether to use the service, yearning and searching for the least harmful service, tailoring the service to the older adult, persuading the older adult to use the service, conforming the older adult to the service and coercing the older adult to use the service. Different strategies were used depending on factors such as desperation in needing respite, willingness to do what is best for the older adult, confidence in taking care of the older adult and the anticipated response of the older adult to services.

Conclusion

Nurses should carefully assess caregivers' strategies in their attempts to encourage service use and should provide adequate assistance in accordance with those strategies.
Modelling landscape dynamics in a glacial refugium – or the spatial and temporal fluctuations of tree line altitudes
Authors: Marta Silvio , Mattoccia Marco , Sbordoni Valerio
Published: April 2013

Aim

To produce a dynamic model of tree line position and habitat suitability for temperate and warm temperate forests, with high spatial and temporal resolution from the Last Glacial Maximum to the present, using an approach based on the quasi‐constant altitudinal difference between the tree line altitude (TLA) and the equilibrium line altitude (ELA) of glaciers.

Location

Central Mediterranean.

Methods

Data sets of current tree line position and ELA were integrated and five different scenarios of tree line shifts were simulated at a millennial scale. The model was parameterized using a dense palynological data set (964 time points, representing 121 pollen sampling sites). The simulated tree line fluctuations were compared with those of the boreal forest reconstructed using field data from the southern Alps.

Results

The reconstructed evolution of TLA yielded good results for the interval of tree line formation (correct assignment rate: lower limit = 98.29%; upper limit = 94.29%) and the best‐fitting scenario within each millennium tree line (combined scenarios: AUC ± 2 SD = 0.877 ± 0.047; Kappa ± 2 SD = 0.651 ± 0.100). There was also strong agreement between the simulated and the reconstructed tree line fluctuations for both the timing and magnitude of tree line shift.

Main conclusions

Although all the analyses support the hypothesis of a quasi‐constant difference between TLA and ELA, we found a major relative upward shift of the tree line position within the interval of tree line formation, probably due to the increase in both precipitation and atmospheric CO2 concentration since the onset of the Bølling–Allerød Interstadial. Palaeodistribution maps may be useful for drawing inferences about the biogeography of single temperate and warm temperate species or for recolonization simulations; however, model‐based inferences will need to account for several variables, including local climate variability, fire and herbivore disturbance, and lack of complete spatial association between modelled forests and species of interest.
Do Racial Preferences Affect Minority Learning in Law Schools?
Authors: Williams Doug
Published: April 2013

An analysis of the The Bar Passage Study (BPS) reveals that minorities are both less likely to graduate from law school and less likely to pass the bar compared to whites even after adjustments are made for group differences in academic credentials. To account for these adjusted racial gaps in performance, some researchers put forward the “mismatch hypothesis,” which proposes that students learn less when placed in learning environments where their academic skills are much lower than the typical student. This article presents new results from the BPS that account for both measurement‐error bias and selection‐on‐unobservables bias that makes it more difficult to find a mismatch effect if in fact one exists. I find much more evidence for mismatch effects than previous research and report magnitudes from mismatch effects more than sufficient to explain racial gaps in performance.
Can We Trust Intuitive Jurors? Standards of Proof and the Probative Value of Evidence in Coherence‐Based Reasoning
Authors: Glöckner Andreas , Engel Christoph
Published: April 2013

Jury members are confronted with highly complex, ill‐defined problems. Coherence‐based reasoning (Pennington &Hastie 1992;Simon 2004), which partially relies on intuitive‐automatic processing, empowers them to nonetheless make meaningful decisions. These processes, however, have a downside. We tested possible negative effects in a set of studies. Specifically, we investigated whether stricter standards of proof are suppressed by stronger coherence shifts and whether the probative value of the evidence is properly taken into account. We found thatU.S.model jury instructions for preponderance of the evidence and beyond a reasonable doubt influence conviction rates in the intended direction and are not undermined by coherence shifts, although probabilistic estimations of these standards are inappropriate. However, even massive changes in explicitly stated probabilities, while holding the overall constellation of facts constant, did not influence conviction rates or the estimated probability of conviction. We argue that reforms in legal procedure should focus on measures to reduce the negative side effects of coherence‐based reasoning in general but, more specifically, to make probabilistic information better evaluable for decisionmakers in law.
Strong Financial Laws Without Strong Enforcement: Is Good Law Always Better than No Law?
Authors: Humphery‐Jenner Mark
Published: April 2013

This article examines whether strong laws are effective when regulatory institutions are weak. This has become especially relevant due to criticisms of financial market regulation in the United States. I test the impact of imposing strong laws on a weak regulatory environment by using China's principled reforms to market manipulation law as a natural experiment. The results from difference‐in‐difference tests suggest that China's principled law reforms did not improve the market's information environment, as proxied by the level of informed trade and information asymmetry. This implies that principled law reform is ineffective if the regulatory environment is weak.
The Citation and Depreciation of U.S. Supreme Court Precedent
Authors: Black Ryan C. , Spriggs James F.
Published: April 2013

An enduring piece of legal wisdom contends that the value of court opinions depreciates as they age and a variety of factors lead some cases to depreciate faster than others. We measure depreciation as the change in the frequency with which Supreme Court cases are cited as a function of their age. We then examine whether the rate of depreciation varies systematically based on ideological considerations, opinion characteristics, and citation history. Our results indicate, first, that precedents depreciate rather quickly and, for example, depreciate about 81 percent and 85 percent between their first and 20th years of age at the Supreme Court and courts of appeals, respectively. Second, few of the variables in our analysis have any appreciable influence on the pace of depreciation. Two variables capturing the citation history of a case have the most notable influence on depreciation, but even their effects are reasonably modest and somewhat short‐lived. Third, while our study focuses on depreciation (i.e., the change in the frequency of citation over time), it also produces an important implication for citation itself (i.e., the number of times a case is cited in a given year). We show that prior studies significantly overestimate the effect of almost every variable used to explain citation rates because those variables become substantially less influential as cases age. Future studies must therefore take into account that the effect of an independent variable on citations is conditional on the age of a precedent. This study therefore contributes to our understanding of the process by which law, as observed through citations to cases, changes.
Weeds mediate the level of intraguild predation in arthropod food webs
Authors: Tixier P. , Dagneaux D. , Mollot G. , Vinatier F. , Duyck P‐F.
Published: April 2013

Intraguild predation, which is common for generalist predators, is a specific form of omnivory that may suppress the biological control of a pest. The dietary flexibility of a given organism depends on the choice of the C3 (banana crop) and the C4 (weeds) pathways they use and on the trophic level on which they feed. Understanding the conditions in which intraguild predation decreases biological control is a major issue in agroecosystems. We tested whether the contribution of different primary producer pathways in diets of generalist predators mediates the level of intraguild predation. We studied 10 agroecosystems in which banana plants (C3 metabolism) were diversely associated with weeds (C4 metabolism). Diversity in litter macrofauna was relatively low, with a mean between three and eight species per trap. Measurement of stable isotopes showed a significant decrease in the δ15N values of generalist predators when the C4 pathway contributed more than the C3 pathway to their diet. We rejected hypotheses that an increase in the abundance of prey and that a decrease in prey's δ15N values occur when the C4 pathway contributes more than the C3 pathway to their diet. The results are consistent with the diet modification hypothesis, that is, intraguild predation is lower when the C4 (weeds) pathway is preferred to the C3 pathway. Our results suggest that when the C4 pathway of weeds is more exploited by herbivores (or detritivores), generalist predators tend to consume these herbivores and thus neglect the intraguild prey. The diverse C4 plant community probably supports a diverse herbivore community that provides alternative prey. Our results provide evidence that increasing plant diversity in agroecosystems should decrease intraguild predation of generalist predators and should therefore improve pest regulation. In an applied perspective, plant diversity could be increased by establishing a more diverse cover‐crop community.
School‐based individualised lifestyle intervention decreases obesity and the metabolic syndrome in Mexican children
Authors: Elizondo‐Montemayor L. , Gutierrez N. G. , Moreno D. M. , Martínez U. , Tamargo D. , Treviño M.
Published: April 2013

Background

Currently, there is limited evidence about effective strategies to manage childhood obesity and the metabolic syndrome in school settings. The present study aims to analyse changes in the prevalence of being overweight/obese and having the metabolic syndrome in relation to a 10‐month lifestyle intervention based on individualised face‐to‐face sessions and parental education in school settings.

Methods

The study sample comprised a cross‐sectional sample of 96 overweight/obese Mexican children aged 6–12 years from eight schools. Clinical, anthropometric measurements and 24‐h recalls were obtained during each of 13 visits. Laboratory measurements were determined at the beginning and end. The energy‐reduced diet was based on dietary recommended intakes. Individualised structured daily meals and a physical activity plan, tailored‐made for each child, were provided every 3 weeks at the schools. Parental attendance was required. Student′s t‐test, McNemar and Shapiro‐Wilk tests and simple linear regression were used for the statistical analysis.

Results

The prevalence of metabolic syndrome fell significantly from 44% to 16% (P < 0.01), high blood pressure fell from 19% to 0%, hypertrigliceridaemia fell from 64% to 35%, high‐density lipoprotein‐cholesterol ≤ 40 fell from 60% to 41%, hyperglycaemia fell from 1% to 0%, and waist circumference ≥90th percentile fell from 72% to 57%. There was a 2.84 [95% confidence interval (CI) = −4.10 to −1.58; P < 0.01] significant decrease in body mass index percentile and in body‐fat percentage (95% CI = −3.31 to −1.55; P < 0.01). Of the overweight children, 32% achieved normal‐weight, whereas 24% of the obese ones converted to overweight and 1% reached normal‐weight. Physical activity increased 16 min day–1 (P = 0.02) and 2 days week–1.

Conclusions

A school‐setting lifestyle intervention led to a decreased prevalence of being overweight/obese and to a striking reduction in the prevalence of the metabolic syndrome in a sample of Mexican children.
Barriers and facilitators to screening for malnutrition by community nurses: a qualitative study
Authors: Green S. M. , James E. P. , Latter S. , Sutcliffe M. , Fader M. J.
Published: April 2013

Background

A substantial proportion of individuals who live in community settings in the UK experience malnutrition. Routine screening for malnutrition by healthcare practitioners has been recommended in many regions. The present study aimed to understand community nurses' perceptions of barriers and facilitators to undertaking nutritional screening.

Methods

A qualitative study was undertaken with a purposive sample of community nurses working in one UK healthcare organisation. Semi‐structured interviews were used to elicit perceptions of barriers and facilitators. Interviews were digitally recorded, anonymised and transcribed. Initial codes were assigned for salient constructs identified in the transcripts, refined by grouping, and a thematic list was developed.

Results

Twenty district nurses and community matrons were interviewed at which time saturation of the data was achieved. Six themes emerged: supportive organisational culture, time and resource to screen and intervene, ease and acceptability of the screening tool, professional judgement as good as screening, the need for training and sharing good practice, and enhancing communication between care settings.

Conclusions

The findings of the present study suggest that screening is more likely to be completed where an organisation is perceived to have a clear expectation that it is undertaken and also demonstrates this through training and availability of resources. The need for a process or tool that nurses find easy to use and relevant to their practice area was highlighted. Further research should examine the effect of the use of a nutritional screening tool by community nurses on nutritional care planning and intervention.
Family quality of life and psychological well‐being in parents of children with autism spectrum disorders: a double ABCX model
Authors: Pozo P. , Sarriá E. , Brioso A.
Published: April 2013

Background

This study examined family quality of life (FQOL) and psychological well‐being from a multidimensional perspective. The proposed model was based on the double ABCX model, with severity of the disorder, behaviour problems, social support, sense of coherence (SOC) and coping strategies as components.

Method

One hundred and eighteen parents (59 mothers and 59 fathers) with a child diagnosed with autism spectrum disorders (ASD) participated in the study. Separate path analyses were performed to evaluate models of FQOL and psychological well‐being for mothers and fathers.

Results

In all models, behaviour problems had a negative indirect effect on adaptation (FQOL and psychological well‐being) through SOC. For both mothers and fathers, the severity of the disorder and social support played significant roles in FQOL models. Coping strategies were related with adaptation, active avoidance coping with FQOL for fathers and positive and problem‐focused coping with psychological well‐being for mothers.

Conclusions

The results of this study highlight the value of the multidimensional approach. The specific patterns of results for mothers and fathers contribute to comprehension of the psychological adaptation of parents. Findings could be taken into account in interventions with families.
Do more hats bring more benefits? Exploring the impact of dual organizational identification on work‐related attitudes and performance
Authors: Chen Yen‐Chun , Chi Shu‐Cheng Steve , Friedman Ray
Published: April 2013

Recent work on organizational identity has recognized the possibility of dual identification. We present an analysis of complementary dual identification, according to which the known positive benefits of employer identification are amplified when there exist strong secondary forms of identification at work. Thus, even though non‐employer identification is weakly associated with beneficial job outcomes, these secondary aspects of non‐employer work identification remain important because they amplify the beneficial impact of employer identification on work attitudes and performance. Using a sample of sales representatives at department stores in Taiwan, we found that the stronger the department‐store identification was, the stronger the positive effects of employing‐company identification on job performance and customer‐oriented behaviour were.

Practitioner points

To enhance employees’ job performance and customer focus, it is important to strengthen their identification with the employing company and the workplace.

The development of employees’ co‐occurring identification with their workplace does not distract them from their work, but rather enhances the benefits of employing‐company identification.

Companies should train their managers to be aware of employees’ dual identification and of methods for strengthening it.

Sales representatives at department stores and in other contexts should be granted a pleasant and attractive work environment, as the benefits of dual identification can be boosted when employees identify with their workplace.
Early developmental outcome following surgery for oesophageal atresia
Authors: Walker Karen , Halliday Robert , Badawi Nadia , Stewart Jan , Holland Andrew JA
Published: April 2013

Aim

To compare the developmental outcome of infants with oesophageal atresia with or without trachea‐oesophageal fistula (OA/TOF) who underwent surgery in early infancy with healthy control infants in New South Wales, Australia.

Methods

Infants diagnosed with OA/TOF requiring surgical intervention were enrolled prospectively between 1 August 2006 and the 31 December 2008. Healthy control infants were enrolled in the same time period. The children underwent a developmental assessment at 1 year of age (corrected) using the Bayley Scales of Infant and Toddler Development (Version III).

Results

Of 34 infants with OA/TOF that were enrolled, 31 had developmental assessments. The majority (75%) were term infants (≥37 weeks gestation) with a mean birth weight of 2717 g. Fourteen infants (44%) had an associated birth defect and one infant with multiple associated anomalies subsequently died. Developmental assessments were also performed on 62 control infants matched for gestational age. Infants with OA/TOF had a mean score significantly lower on the expressive language subscale (P < 0.05) compared with the control infants.

Conclusions

This study found a lower than expected developmental score for infants following surgery for OA/TOF in the expressive language subscale compared with the healthy control infants. These findings support concerns over the potential impact of OA/TOF and its effects on development. Further studies, including continuing developmental review to determine whether these differences persist and their functional importance, should be performed.
Application of Adaptive Cluster Sampling with a Data‐Driven Stopping Rule to Plant Disease Incidence
Authors: Gattone Stefano Antonio , Esha Mohamed , Mwangi Jesse Wachira
Published: April 2013

Plant pathologists need to manage plant diseases at low incidence levels. This needs to be performed efficiently in terms of precision, cost and time because most plant infections spread rapidly to other plants. Adaptive cluster sampling with a data‐driven stopping rule (ACS*) was proposed to control the final sample size and improve efficiency of the ordinary adaptive cluster sampling (ACS) when prior knowledge of population structure is not known. This study seeks to apply the ACS* design to plant diseases at various levels of clustering and incidences levels. Results from simulation study show that the ACS* is as efficient as the ordinary ACS design at low levels of disease incidence with highly clustered diseased plants and is an efficient design compared with simple random sampling (SRS) and ordinary ACS for some highly to less clustered diseased plants with moderate to higher levels of disease incidence.
Conversion of α‐linolenic acid to long‐chain omega‐3 fatty acid derivatives and alterations of HDL density subfractions and plasma lipids with dietary polyunsaturated fatty acids in Monk parrots (Myiopsitta monachus)
Authors: Petzinger C. , Larner C. , Heatley J. J. , Bailey C. A. , MacFarlane R. D. , Bauer J. E.
Published: April 2013

The effect of α‐linolenic acid from a flaxseed (FLX)‐enriched diet on plasma lipid and fatty acid metabolism and possible atherosclerosis risk factors was studied in Monk parrots (Myiopsitta monachus). Twenty‐four Monk parrots were randomly assigned to diets containing either 10% ground SUNs or 10% ground FLXs. Feed intake was calculated daily. Blood samples, body condition scores and body weights were obtained at −5 weeks, day 0, 7, 14, 28, 42 and 70. Plasma samples were analysed for total cholesterol, free cholesterol, triacylglycerols and lipoproteins. Phospholipid subfraction fatty acid profiles were determined. By day 70, the FLX group had significantly higher plasma phospholipid fatty acids including 18:3n‐3 (α‐linolenic acid), 20:5n‐3 (eicosapentaenoic acid) and 22:6n‐3 (docosahexaenoic acid). The sunflower group had significantly higher plasma phospholipid levels of 20:4n‐6 (arachidonic acid). By day 70, the high‐density lipoprotein (HDL) peak shifted resulting in significantly different HDL peak densities between the two experimental groups (1.097 g/ml FLX group and 1.095 g/ml SUN group, p = 0.028). The plasma fatty acid results indicate that Monk parrots can readily convert α‐linolenic acid to the long‐chain omega‐3 derivatives including docosahexaenoic acid and reduce 20:4n‐6 accumulation in plasma phospholipids. The reason for a shift in the HDL peak density is unknown at this time.
Gene expression and phenotypic traits of Aggregatibacter actinomycetemcomitans in response to environmental changes
Authors: Longo P. L. , Nunes A. C. R. , Umeda J. E. , Mayer M. P. A.
Published: April 2013

Background and Objective

Periodontopathogens experience several challenges in the oral cavity that may influence their transcription profile and resulting phenotype. This study evaluated the effect of environmental changes on phenotype and gene expression in a serotype b Aggregatibacter actinomycetemcomitans isolate.

Material and Methods

Cultures in early exponential phase and at the start of stationary growth phase in microaerophilic and anaerobic atmospheres were evaluated. Cell hydrophobic properties were measured by adherence to n‐hexadecane; in addition, adhesion to, and the ability to invade, KB cells was evaluated. Relative transcription of 12 virulence‐associated genes was determined by real‐time reverse transcritption quantitative PCR.

Results

The culture conditions tested in this study were found to influence the phenotypic and genotypic traits of A. actinomycetemcomitans. Cells cultured in microaerophilic conditions were the most hydrophobic, reached the highest adhesion efficiency and showed up‐regulation of omp100 (which encodes an adhesion) and pga (related to polysaccharide synthesis). Cells grown anaerobically were more invasive to epithelial cells and showed up‐regulation of genes involved in host‐cell invasion or apoptosis induction (such as apaH, omp29, cagE and cdtB) and in adhesion to extracellular matrix protein (emaA).

Conclusion

Environmental conditions of different oral habitats may influence the expression of factors involved in the binding of A. actinomycetemcomitans to host tissues and the damage resulting thereby, and thus should be considered in in‐vitro studies assessing its pathogenic potential.
Plasma pharmacokinetics of alfaxalone after a single intraperitoneal or intravenous injection of Alfaxan® in rats
Authors: Lau C. , Ranasinghe M. G. , Shiels I. , Keates H. , Pasloske K. , Bellingham M. C.
Published: April 2013

Alfaxalone (3α‐hydroxy‐5α‐pregnane‐11, 20‐dione) is a neuroactive steroid with anaesthetic properties and a wide margin of safety. The pharmacokinetic properties of alfaxalone administered intravenously and intraperitoneally in rats (n = 28) were investigated. Mean t1/2elim for 2 and 5 mg/kg i.v. was 16.2 and 17.6 min, respectively, but could not be estimated for IP dosing, due to sustained plasma levels for up to 60 min after injection. Clp for i.v. injection was calculated at 57.8 ± 23.6 and 54.3 ± 6.8 mL/min/kg, which were 24.5% and 23% of cardiac output, respectively. The observed Cmax was 3.0 mg/L for IP administration, and 2.2 ± 0.9 and 5.2 ± 1.3 mg/L for 2 and 5 mg/kg i.v. administration, respectively. AUC0–60 was 96.2 min·mg/L for IP dosing. The relative bioavailability for IP dosing was 26% and 28% compared to i.v. dosing. Differences in t1/2elim and Clp from previous pharmacokinetic studies in rats are likely due to variations in alfaxalone formulation rather than sex differences. Alfaxan® given IP caused sustained levels of alfaxalone, no apnoea and longer sleep times than i.v. dosing, although immobilization was not induced in 30% of rats given Alfaxan® IP. A pharmacodynamic study of the effects of combining IP injection of Alfaxan® with other premedication agents is worthwhile, to determine whether improved anaesthesia induction could ultimately provide an alternative anaesthetic regimen for rats.
Sharing personalised stories on iPads: a close look at one parent–child interaction
Authors: Kucirkova Natalia , Messer David , Sheehy Kieron , Flewitt Rosie
Published: April 2013

Little is known about how specific iPad applications affect parent–child story‐sharing interactions. This study utilises a case‐study approach to provide an insight into the patterns of interaction, which emerge when a mother and her 33‐month‐old daughter share a self‐created, audio‐visual ‘iPad story’. Multimodal analysis allowed us to gain insights into the complex interaction patterns orchestrated in this new, personalised story‐sharing medium. We found that the app‐mediated story‐sharing context produced a harmonious and smooth interaction, achieving a coherence that is typical of ‘happy’ oral stories. We suggest that the observed interaction resembles that of experiencing a piece of art, and we highlight the need for a holistic approach to understanding the implications for research and practice of children's interactions during multimedia story sharing.
Laboratory‐based scoring system for prediction of hepatic inflammatory activity in patients with autoimmune hepatitis
Authors: Gutkowski Krzysztof , Hartleb Marek , Kacperek‐Hartleb Teresa , Kajor Maciej , Mazur Włodzimierz , Zych Włodzimierz , Walewska‐Zielecka Bożena , Habior Andrzej , Sobolewski Marek
Published: April 2013

Background & Aims

In autoimmune hepatitis (AIH), inflammation is closely related to fibrosis. Although transaminase levels are commonly used to assess hepatic inflammation, they may not relate directly to the histology. We developed a noninvasive diagnostic score as an alternative to liver biopsy to help optimize treatment for AIH and monitor disease progress.

Methods

Eighty‐two participants with type 1 AIH who had undergone liver biopsy were included (44 in training and 38 in validation sets). Liver histology was assessed according to the histologic activity index (HAI; score 0–18) and Ishak's histologic fibrosis index (HFI; score 0–6). High inflammation was defined as HAI>4, and advanced fibrosis was defined as HFI>2. Routine laboratory test findings and stepwise linear regression were used to develop the best models predicting HAI and HFI. The best cut‐off value to predict high inflammation and advanced fibrosis for these formulas was then calculated based on receiver‐operating characteristic analysis.

Results

The cut‐off value for a model predicting high inflammation was ≥3.57 (AUROC = 0.93; 95% CI: 0.86–1.00), with 100% sensitivity and 85% specificity. High inflammation was confirmed with an 81% positive predictive value and excluded with a 100% negative predictive value. In the validation set, the sensitivity, specificity, positive predictive value and negative predictive values were 100, 56, 88 and 100% respectively. The diagnostic yield of the fibrosis score was unsatisfactory.

Conclusions

The noninvasive inflammatory score based on four routine laboratory parameters discriminated patients with and without significant hepatic inflammation and may facilitate follow‐up of type 1 AIH patients.
Non‐alcoholic fatty liver disease independently predicts prediabetes during a 7‐year prospective follow‐up
Authors: Zelber‐Sagi Shira , Lotan Roni , Shibolet Oren , Webb Muriel , Buch Assaf , Nitzan‐Kaluski Dorit , Halpern Zamir , Santo Erwin , Oren Ran
Published: April 2013

Background & Aims

Non‐alcoholic fatty liver disease (NAFLD) is suspected to confer an increased risk for developing type 2 diabetes (DM). However, only a few prospective studies evaluated NAFLD as a predictor for DM, most did not adjust for the full range of potential cofounders and none used an objectively quantified degree of steatosis. Our aim was to evaluate the independent role of NAFLD in predicting the development of pre‐DM in a 7‐year prospective follow‐up of healthy volunteers.

Methods

A prospective cohort of a subsample of the Israeli National Health Survey evaluated at baseline and after 7 years by identical protocols. Metabolic parameters and ultrasonographic evidence of NAFLD were evaluated in 213 subjects, without known liver disease or history of alcohol abuse. Exclusion criteria were pre‐DM at the baseline survey. Steatosis was quantified by ultrasound with the hepato‐renal ultrasound index (HRI).

Results

The study included 141 volunteers (mean age 48.78 ± 9.68, 24.82% with NAFLD) without pre‐DM/DM at baseline. Both NAFLD on regular US (OR=2.93, 1.02–8.41 95%CI) and HRI (OR=7.87, 1.83–33.82) were independent predictors for the development of pre‐DM, adjusting for age, gender, BMI, family history of DM, baseline insulin, adiponectin and glucose. Further adjustment for physical activity and dietary intake did not weaken the association. Furthermore, NAFLD was a stronger predictor for pre‐DM than the metabolic syndrome. Subjects with both NAFLD and glucose ≥89 had 93.3% incidence rate of pre‐DM.

Conclusion

Non‐alcoholic fatty liver disease is a strong and independent risk factor for pre‐DM in the general adult population; thus, NAFLD patients should be classified as a population at risk.
Loss of Focal Adhesion Kinase Enhances Endothelial Barrier Function and Increases Focal Adhesions
Authors: Arnold Kimberly M. , Goeckeler Zoe M. , Wysolmerski Robert B.
Published: April 2013

Objective

To determine the role of FAK in the regulation of endothelial barrier function.

Methods

Stable FAK knockdown HLEC were generated by lentiviral infection of FAK shRNA. Measurements of isometric tension and transendothelial electrical resistance were performed.

Results

A FAK knockdown human pulmonary endothelial cell line was generated by lentiviral infection with FAK shRNA and resulted in greater than 90% reduction in FAK protein with no change in Pyk2 protein. Loss of FAK altered cell morphology and actin distribution in both pre‐ and post‐confluent endothelial cells. Large, polygonal shaped endothelial cells with randomly organized stress fibers were identified in pre‐confluent cultures, while in confluent monolayers, endothelial cells were irregularly shaped with actin bundles present at cell margins. An increase in the number and size of vinculin plaques was detected in FAK‐depleted cells. FAK knockdown monolayers generated a greater transendothelial electrical resistance than controls. Thrombin treatment induced similar changes in TER in both FAK knockdown and control cell lines. FAK‐depleted endothelial cells developed a higher stable basal isometric tension compared to control monolayers, but the increase in tension stimulated by thrombin does not differ between the cell lines. Basal myosin II regulatory light chain phosphorylation was unaltered in FAK‐depleted cells. In addition, loss of FAK enhanced VE‐cadherin localization to the cell membrane without altering VE‐cadherin protein levels.

Conclusions

The loss of FAK in endothelial cells enhanced cell attachment and strengthened cell‐cell contacts resulting in greater basal tension leading to formation of a tighter endothelial monolayer.