bluuebunny/crossref_metadata_2025 huggingface dataset:
Curaua leaf fiber (Ananas comosusvar.erectifolius) reinforcing poly(lactic acid) biocomposites: Formulation and performance
Authors: de Araujo Marco Antonio Moreira , de Sena Neto Alfredo Rodrigues , Hage Elias , Mattoso Luiz Henrique Capparelli , Marconcini José Manoel
Published: April 2014

Formulations of poly(lactic acid) (PLA) reinforced by curaua leaf fibers were prepared and characterized. This biocomposite has material characteristics such as biodegradability and renewability. This work aimed to develop a PLA/curaua leaf fiber composite as a sustainable biodegradable polymer composite. The PLA and composites were thermally, mechanically, and morphologically evaluated. The critical fiber length was studied to check its influence on the mechanical properties. Predictions of the Young's modulus were done to compare with the experimental data, having a reasonable agreement. The Young's modulus increased above 70%, and the impact strength increased 20% compared with the pure PLA. Thermal analysis showed that formulations with up to 20% by weight of fibers were more thermally stable. The fiber modified the crystallinity of the PLA matrix. The best overall balance of properties was attained in composites containing 15% curaua fiber. POLYM. COMPOS., 36:1520–1530, 2015. © 2014 Society of Plastics Engineers
First‐trimester maternal factors and biomarker screening for preeclampsia
Authors: Poon Leona C. , Nicolaides Kypros H.
Published: April 2014

Preeclampsia (PE), which affects about 2% of pregnancies, is a major cause of maternal and perinatal morbidity and mortality. PE can be subdivided into early onset PE with delivery <34 weeks' gestation and late onset PE with delivery ≥34 weeks. Early onset PE is associated with a higher incidence of adverse outcome. This review illustrates that effective screening for the development of early onset PE can be provided in the first‐trimester of pregnancy. Screening by a combination of maternal risk factors, mean arterial pressure, uterine artery Doppler, maternal serum pregnancy‐associated plasma protein‐A and placental growth factor can identify about 95% of cases of early onset PE for a false‐positive rate of 10%. © 2014 John Wiley & Sons, Ltd.
Back amorphous‐crystalline silicon heterojunction (BACH) photovoltaic device with facile‐grown oxide ‐ PECVD SiNx passivation
Authors: Chowdhury Zahidur R , Kherani Nazir P
Published: April 2014

This article reports on the integration of facile native oxide‐based passivation of crystalline silicon surfaces within the back amorphous‐crystalline silicon heterojunction solar cell concept. The new passivation scheme consists of 1‐nm thick native oxide and nominally 70‐nm thick PECVD silicon nitride. The low temperature passivation scheme provides uniform high quality surface passivation and low parasitic optical absorption. The interdigitated doped hydrogenated amorphous silicon layers were deposited on the rear side of the silicon wafer using the direct current saddle field PECVD technique. A systematic analysis of a series of back amorphous‐crystalline silicon heterojunction cells is carried out in order to examine the influence of the various cell parameters (interdigital gap, n‐doped region width, ratio of widths of p, and n‐doped regions) on cell performance. A photovoltaic conversion efficiency of 16.7 % is obtained for an untextured cell illuminated under AM 1.5 global spectrum (cell parameters: VOC of 641 mV, JSC of 33.7 mA‐cm  − 2 and fill factor of 77.3 %). Copyright © 2014 John Wiley & Sons, Ltd.
Failure analysis of Cu(In,Ga)Se2 photovoltaic modules: degradation mechanism of Cu(In,Ga)Se2 solar cells under harsh environmental conditions
Authors: Lee Dong‐Won , Cho Won‐Ju , Song Jun‐Kwang , Kwon Oh‐Yun , Lee Won‐Hee , Park Chi‐Hong , Park Kyung‐Eun , Lee Heesoo , Kim Yong‐Nam
Published: April 2014

High‐temperature‐induced and humidity‐induced degradation behaviors were investigated through the failure analysis of encapsulated Cu(In,Ga)Se2 (CIGS) modules and non‐encapsulated CIGS cells. After being exposed to high temperature (85 °C) for 1000 h, the efficiency loss of CIGS modules and the resistivities of the aluminum‐doped zinc oxide (AZO) layer, CIGS layer, and Mo layer were slightly increased. After damp heat (DH) testing (85 °C/85% RH), the efficiency of some modules decreased significantly accompanied by discoloration, and in these areas, the resistivity of the AZO layers increased markedly. The causes of degradation of CIGS cells after high temperature and DH tests were suggested through X‐ray photoelectron spectroscopy analysis. The high‐temperature‐induced degradation behaviors were revealed to be increases in series resistance of the CIGS cells, due to the adsorption of oxygen on the AZO, CIGS, and Mo layers. The degradation behavior after DH (85 °C/85% RH) exposure was caused by the adsorption of oxygen, as well as the generation of Zn(OH)2 due to water molecules. In particular, the humidity‐induced degradation behavior in discolored CIGS modules was ascribed to the generation of Zn(OH)2 and carboxylic acids in the AZO layer, due to a chemical reaction between the AZO, ethylene‐vinyl acetate copolymer, and water. Copyright © 2014 John Wiley & Sons, Ltd.
Nitric‐oxide‐mediated cell death is triggered by chitosan in Fusarium eumartii spores
Authors: Terrile María Cecilia , Mansilla Andrea Yamila , Albertengo Liliana , Rodríguez María Susana , Casalongué Claudia Anahí
Published: April 2014

BACKGROUND

The genus Fusarium comprises a heterogeneous group of fungi important for agriculture. Fusarium solani f. sp. eumartii (F. eumartii), historically considered to be a fungal pathogen of potato, has also been associated with tomato disease. Currently, chitosan and its derivatives have been receiving more attention as environmentally friendly antimicrobial compounds in sustainable practices. The aim of the present work was to characterize downstream events associated with the mode of action of chitosan, including nitrosative reactive species, in order to identify new biomarkers of its cytotoxic action.

RESULTS

Data indicated that chitosan‐mediated nitric oxide (NO) production might lead to conidial death, concomitant with the strong reduction in fungal pathogenicity in tomato plants. Following chitosan applications, a notably dose‐dependent reduction in conidial viability was demonstrated in F. eumartii. Thereafter, the infectivity of chitosan‐treated spores was tested by a bioassay using tomato seedlings.

CONCLUSION

All these data highlight NO valuable properties as a quantitative and qualitative biomarker of cytotoxic action of chitosan in conidial cells. In addition, these findings place the chitosan assayed here as a fungicide with a high potential of application in sustainable horticultural practices. © 2014 Society of Chemical Industry
Deletion of the carboxyl‐terminal residue disrupts the amino‐terminal folding, self‐association, and thermal stability of an amphipathic antimicrobial peptide
Authors: Lee Chang‐Shin , Tung Wei‐Cheng , Lin Yu‐Hsin
Published: April 2014

Understanding the complex relationship between amino acid sequence and protein behaviors, such as folding and self‐association, is a major goal of protein research. In the present work, we examined the effects of deleting a C‐terminal residue on the intrinsic properties of an amphapathic α‐helix of mastoparan‐B (MP‐B), an antimicrobial peptide with the sequence LKLKSIVSWAKKVL‐NH2. We used circular dichroism and nuclear magnetic resonance to demonstrate that the peptide MP‐B[1‐13] displayed significant unwinding at the N‐terminal helix compared with the parent peptide of MP‐B, as the temperature increased when the residue at position 14 was deleted. Pulsed‐field gradient nuclear magnetic resonance data revealed that MP‐B forms a larger diffusion unit than MP‐B[1‐13] at all experimental temperatures and continuously dissociates as the temperature increases. In contrast, the size of the diffusion unit of MP‐B[1‐13] is almost independent of temperature. These findings suggest that deleting the flexible, hydrophobic amino acid from the C‐terminus of MP‐B is sufficient to change the intrinsic helical thermal stability and self‐association. This effect is most likely because of the modulation of enthalpic interactions and conformational freedom that are specified by this residue. Our results implicate terminal residues in the biological function of an antimicrobial peptide. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
Confidence intervals around Bayes Cost in multi‐state diagnostic settings to estimate optimal performance
Authors: Batterton Katherine A. , Schubert Christine M.
Published: April 2014

A critical feature of diagnostic testing is correctly classifying subjects based upon specified thresholds of some measure. The commonly employed Youden index determines a test's optimal thresholds by maximizing the correct classification rates for a diagnostic scenario. An alternative to the Youden index is the cost function, Bayes Cost (BC). BC determines a test's optimal setting by minimizing the sum of all misclassification rates from the test. Unlike the Youden index, BC can consider a priori costs of all the diagnostic outcomes including class specific misclassifications regardless of the number of classes. Delta method approximate confidence intervals around BC are derived under the assumption of normally distributed classes as a means for quantifying a test's performance and comparing classifiers at their optimal settings in a multi‐state diagnostic framework. A simulation study is conducted to demonstrate the performance of the derived confidence intervals that are found to perform well, especially for sample sizes of 50 or larger in each diagnostic class. Finally, the proposed methods are applied to a four‐class breast tissue classification problem, where four possible discriminatory features are compared under varying decision cost structures. Using the confidence intervals around BC, the best feature for classification is selected, and the optimal thresholds and their 95% confidence intervals are determined. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Augmented mixed beta regression models for periodontal proportion data
Authors: Galvis Diana M. , Bandyopadhyay Dipankar , Lachos Victor H.
Published: April 2014

Continuous (clustered) proportion data often arise in various domains of medicine and public health where the response variable of interest is a proportion (or percentage) quantifying disease status for the cluster units, ranging between zero and one. However, because of the presence of relatively disease‐free as well as heavily diseased subjects in any study, the proportion values can lie in the interval [0,1]. While beta regression can be adapted to assess covariate effects in these situations, its versatility is often challenged because of the presence/excess of zeros and ones because the beta support lies in the interval (0,1). To circumvent this, we augment the probabilities of zero and one with the beta density, controlling for the clustering effect. Our approach is Bayesian with the ability to borrow information across various stages of the complex model hierarchy and produces a computationally convenient framework amenable to available freeware. The marginal likelihood is tractable and can be used to develop Bayesian case‐deletion influence diagnostics based onq‐divergence measures. Both simulation studies and application to a real dataset from a clinical periodontology study quantify the gain in model fit and parameter estimation over other ad hoc alternatives and provide quantitative insight into assessing the true covariate effects on the proportion responses. Copyright © 2014 John Wiley & Sons, Ltd.
Large‐Field‐of‐View Wide‐Spectrum Artificial Reflecting Superposition Compound Eyes
Authors: Huang Chi‐Chieh , Wu Xiudong , Liu Hewei , Aldalali Bader , Rogers John A. , Jiang Hongrui
Published: April 2014

In nature, reflecting superposition compound eyes (RSCEs) found in shrimps, lobsters and some other decapods are extraordinary imaging systems with numerous optical features such as minimum chromatic aberration, wide‐angle field of view (FOV), high sensitivity to light and superb acuity to motion. Here, we present life‐sized, large‐FOV, wide‐spectrum artificial RSCEs as optical imaging devices inspired by the unique designs of their natural counterparts. Our devices can form real, clear images based on reflection rather than refraction, hence avoiding chromatic aberration due to dispersion by the optical materials. Compared to imaging at visible wavelengths using conventional refractive lenses of comparable size, our artificial RSCEs demonstrate minimum chromatic aberration, exceptional FOV up to 165° without distortion, modest aberrations and comparable imaging quality without any post‐image processing. Together with an augmenting cruciform pattern surrounding each focused image, our large‐FOV, wide‐spectrum artificial RSCEs possess enhanced motion‐tracking capability ideal for diverse applications in military, security, medical imaging and astronomy.
An empirical evaluation of a three‐tier conduit framework for multifaceted test case classification and selection using fuzzy‐ant colony optimisation approach
Authors: Kumar Manoj , Sharma Arun , Kumar Rajesh
Published: April 2014

The test case optimisation is an NP‐complete, knowledge‐driven, data‐driven, and multidimensional search space partitioning and dimension reduction problem. In the multifaceted test case classification, partitioning and reducing the multidimensional test case fitness search space is the critical problem. The vague nature of fitness parameters, conflicting nature objectives, and ambiguity in the test case fitness evaluation have created and increased the uncertainty, the imprecision, and the incompleteness in the test case classification and selection. Because of the increasing ambiguity, the complexity, and the cost of software testing, automated test case classification and selection has emerged as an appropriate tool to classify test cases into predefined categories using the multifaceted concept. Most of the test cases affecting the performance of the classifier are irrelevant and redundant. A strong need therefore exists to devise an intelligent technique to identify and remove test cases affecting the performance of the classifier. For increasing the performance of classifier, multifaceted test case selection is used to reduce fitness search space to be searched. In this paper, a three‐tier sequential framework is proposed for a multifaceted test case classification and selection. The first stage of the proposed framework is the fuzzy synthesis‐based filtration approach for multifaceted test case fitness evaluation and classification. The second stage of the proposed framework is the fuzzy entropy‐based filtration technique with a backward search strategy, used for estimating and reducing the ambiguity in test case fitness evaluation, classification, and selection. The third stage of the proposed framework is the ant colony optimisation‐based wrapper technique with a forward search strategy, employed to select test cases from the output (reduced) test suite by the second stage. The proposed framework is tested on artefacts of benchmark applications. The results of the empirical study clearly show that the third stage of our proposed method outperforms the second and first stages, and the performance of the algorithms used in all three stages increases on average as the stages are escalating. The classification accuracy is enhanced by reducing the ambiguity in fitness and the classification of test cases, increasing the number of test cases accurately classified, and reducing the number in the test case pool to be exercised. Copyright © 2014 John Wiley & Sons, Ltd.
In vivo performance of a novel silk fibroin scaffold for partial meniscal replacement in a sheep model
Authors: Gruchenberg Katharina , Ignatius Anita , Friemert Benedikt , von Lübken Falk , Skaer Nick , Gellynck Kris , Kessler Oliver , Dürselen Lutz
Published: April 2014

Purpose

Due to the negative effects of meniscectomy, there is a need for an adequate material to replace damaged meniscal tissue. To date, no material tested has been able to replace the meniscus sufficiently. Therefore, a new silk fibroin scaffold was investigated in an in vivo sheep model.

Methods

Partial meniscectomy was carried out to the medial meniscus of 28 sheep, and a scaffold was implanted in 19 menisci (3-month scaffold group,n = 9; 6-month scaffold group,n = 10). In 9 sheep, the defect remained empty (partial meniscectomy group). Sham operation was performed in 9 animals.

Results

The silk scaffold was able to withstand the loads experienced during the implantation period. It caused no inflammatory reaction in the joint 6 months postoperatively, and there were no significant differences in cartilage degeneration between the scaffold and sham groups. The compressive properties of the scaffold approached those of meniscal tissue. However, the scaffolds were not always stably fixed in the defect, leading to gapping between implant and host tissue or to total loss of the implant in 3 of 9 cases in each scaffold group. Hence, the fixation technique needs to be improved to achieve a better integration into the host tissue, and the long-term performance of the scaffolds should be further investigated.

Conclusion

These first in vivo results on a new silk fibroin scaffold provide the basis for further meniscal implant development. Whilst more data are required, there is preliminary evidence of chondroprotective properties, and the compressive properties and biocompatibility are promising.
Juvenile social play and yearling behavior and reproductive success in female Belding’s ground squirrels
Authors: Nunes Scott
Published: April 2014

Benefits of play behavior have been described for individuals during the juvenile period; however, it is less clear whether benefits of juvenile play commonly extend beyond the period of juvenile development. I evaluated possible associations between juvenile social play and yearling maternal territorial behavior and reproductive success in female Belding’s ground squirrels (Urocitellus beldingi). Higher rates of juvenile social play were associated with greater intensity of territorial aggressive and vigilant behavior during gestation but not later phases of the yearling reproductive cycle, suggesting that both juvenile play and later experience may influence maternal territorial behavior in yearling females. Juvenile social play was also a reliable predictor of whether a yearling female successfully weaned a litter, raising the possibility that juvenile play behavior influences yearling reproductive success via effects on maternal territorial behavior in femaleU. beldingi. Other factors were also related to reproductive success in yearling females. Body mass at the beginning of the yearling reproductive period was not correlated with juvenile social play but was associated with the likelihood of successfully weaning a litter. Yearling females whose mother was still alive were more likely to wean a litter than those whose mother was not alive. Mothers and yearling daughters tended to have maternal territories near each other, and mothers with a surviving yearling daughter expressed aggressive behavior at elevated rates and directed aggression toward intruders on the daughter’s territory. Overall, results of the study suggest that juvenile social play is among the variables that influence maternal territorial behavior and reproductive success in yearling femaleU. beldingi, and are consistent with the idea that juvenile play has benefits beyond the juvenile period for femaleU. beldingi.
Amyotrophic Lateral Sclerosis in a Patient with a Family History of Huntington Disease: Genetic Counseling Challenges
Authors: Smith Andrea L. , Teener James W. , Callaghan Brian C. , Harrington Jack , Uhlmann Wendy R.
Published: April 2014

Amyotrophic lateral sclerosis (ALS) and Huntington disease (HD) are generally considered to be distinct and easily differentiated neurologic conditions. However, there are case reports of the co‐occurrence of ALS with HD. We present a 57‐year‐old male with a clinical diagnosis of sporadic ALS in the context of a family history of HD. This case adds to the limited literature regarding individuals with a family history of HD who present with features of ALS. There were several genetic counseling challenges in counseling this patient including the diagnostic consideration of two fatal conditions, complex risk information, the personal and familial implications, and the patient's inability to communicate verbally or through writing due to disease progression. DNA banking effectively preserved the right of our patient and his wife not to learn his HD genetic status during a stressful time of disease progression while providing the option for family members to learn this information in the future if desired. We present lessons learned and considerations for other clinical genetics professionals who are presented with similar challenging issues.
Direct seeding of dry forest tree species in abandoned pastures: effects of grass canopy and seed burial on germination
Authors: de Souza Gomes Guarino Ernestino , Scariot Aldicir
Published: April 2014

Natural tree regeneration in abandoned pastures can be hampered by various biotic and abiotic filters, including seed removal and predation. We tested the effects of maintenance and removal of grass and seed deposition (buried and unburied) on seed germination of 12 tree species in dry forest pastures. We obtained evidence supporting the hypothesis that seeds attain higher germination under a grass canopy than on bare ground. For most species, grass cover provides safety from seed predators and facilitates germination by providing a suitable microclimate with soil humidity similar to the forest. The hypothesis that buried seeds attain higher germination was not supported by our data. Predation and removal of unburied seeds ranged from 0 to 77 % and, alone or together, were the major causes of non‐germination. Direct seeding is a promising technique for revegetation of recently abandoned pastures in areas originally covered by tropical dry forests. The high germination rate of seeds deposited on the ground and under grass reduces costs during initial restoration stages, potentially facilitating the spread and use of this technique.
Costs and constraints in aphid‐ant mutualism
Authors: Yao Izumi
Published: April 2014

While many studies have demonstrated that ants provide beneficial services to aphids, Bristow (Ant‐plant interactions, Oxford University Press, Oxford, 104–119,1991) first questioned why so few aphid species are ant‐attended. Phylogenetic trees have demonstrated multiple gains and loss of ant‐attendance in the course of aphid‐ant interactions, implying that mutualisms easily form and dissolve. Several studies have reported the factors that influence the formation and maintenance of aphid‐ant interactions. Examples include the physiological costs of ant attendance, competition for mutualistic ants, ant predation on aphids, the influence of host plants, and parasitoid wasps. Recent physiological techniques have also revealed the chemical component of aphid‐ant mutualisms. The honeydew of ant‐attended aphids contains melezitose (a trisaccharide), which has an important role in aphid‐ant interactions. Studies of cuticular hydrocarbons on aphids and ants have clarified the underlying mechanisms of ant predation on aphids. Attending ants also reduce aphid dispersal ability, causing the formation of fragmented aphid populations with low genetic diversity in each population. The reduced aphid dispersal could be partly explained by higher wing loading and reduction of flight apparatus due to ant attendance. Whether ant attendance is associated with the range of host plants of aphids or genetic variation in microorganism in aphids remain to be explored.
Bringing the World to the Classroom through Videoconferencing and Project-based Learning
Authors: Hopper Susan B.
Published: April 2014

The focus of this paper is a case study of a Texas-based school that implemented global projects to connect their students with many states and countries as a platform for integrating collaboration and communication skills, technology tools, and cultural diversity into an existing curriculum. The school introduced videoconferencing at every grade level K-8 in a school-wide initiative to bring the world to the classroom through the engagement of global learning projects with distant partners. A rubric is presented that provides a framework for improvement of interaction and engagement in videoconferencing experiences to develop best practices. For the purposes of this paper, the value of global projects in K-4 will be discussed.
Effects of Regioselectivity and Lipid Class Specificity of Lipases on Transesterification, Exemplified by Biodiesel Production
Authors: Šinkūnienė Dovilė , Adlercreutz Patrick
Published: April 2014

Lipase‐catalyzed ethanolysis of triolein was studied as a model for biodiesel production. Four lipases were immobilized on porous polypropylene, and ethanolysis reactions were carried out in methyl t‐butyl ether. The reaction products were analyzed using gas chromatography. Three of the four lipases studied were efficient in the conversion of triolein to 2‐monoolein, but slow in the final step of producing glycerol. However, Candida antarctica lipase B was slow in the conversion of triolein, but more efficient in the subsequent two steps than the other lipases. The 1,3‐selectivity of the lipases was less pronounced for the monooleins than for triolein. Silica gel was investigated as a catalyst for acyl migration, showing an increase in biodiesel yield with three of the lipases, but a reduction in yield when C. antarctica lipase B was used. The highest biodiesel yield (96 %) was obtained with a combination of Rhizopus arrhizus lipase and C. antarctica lipase B.
Leveraging Hospital Formularies for Improved Prescribing
Authors: Karas Albert , Kuehl Bonnie
Published: April 2014

Hospital formularies, guided by the Pharmacy and Therapeutics Committee, exist to optimize medication use by identifying and designating drugs of choice to guide rational prescribing, ultimately reducing patient risk and costs and improving patient outcomes. Guidelines and a framework exist to guide critical evaluations of medications for formulary listing; however, there may be opportunities to improve and standardize how a formulary change could be instituted in Canadian hospitals. A formulary change at an Ontario hospital revealed that there are some key challenges to the formulary change process including the importance of a robust project plan, appropriate resources, healthcare staff education, and acceptance.
The Power of Engagement: Creating the Culture That Gets Your Staff Aligned and Invested
Authors: Studer Quint , Hagins Mitch , Cochrane Bonnie S.
Published: April 2014

The Canadian government officially recognizes the value of staff engagement in providing better healthcare. Evidence demonstrates that engagement is connected to improved financial outcomes as well as better patient safety and clinical outcomes. There is a need for health leaders to create organizational cultures that simultaneously result in higher rates of employee and physician engagement, better clinical care, and lower costs. This article highlights the research and experience gained on the benefits of engagement, explores Studer Group's approach to improving both engagement and quality, and shares the results achieved by the firm's Canadian partners. In addition, it describes some of the “building blocks” that, together, create the necessary cultures of engagement inside organizations.
L'intérêt des formulaires des hôpitaux pour améliorer les pratiques de prescription
Authors: Karas Albert , Kuehl Bonnie
Published: April 2014

Les formulaires des hôpitaux, orientés par les comités pharmaceutiques et thérapeutiques, sont créés pour optimiser l'utilisation des médicaments, car ils déterminent et désignent les médicaments de choix pour favoriser des prescriptions rationnelles, limiter les risques pour le patient, réduire les coûts et améliorer les résultats cliniques. Des lignes directrices et un cadre guident les évaluations critiques des médicaments inscrits dans la liste de formulaires. Cependant, il est peut-être possible d'améliorer et de standardiser le mode d'adoption d'un changement aux formulaires dans les hôpitaux canadiens. Le changement au formulaire d'un hôpital ontarien a révélé de graves problèmes associés à ce processus, y compris l'importance d'un plan d'exécution solide, de ressources adaptées, de la formation du personnel soignant et de l'acceptation.
L'effet de l'adoption tardive des innovations canadiennes: Le cas des moniteurs cardiaques implantables
Authors: Sadri Hamid , Winsor Pamela
Published: April 2014

La syncope est une perte de connaissance subite et généralement momentanée qui peut avoir de graves effets indésirables. Les effets d'une syncope peuvent varier entre une chute et un accident fatal. La syncope nuit énormément à la qualité de vie liée à la santé du patient. Son fardeau sur le système de santé est considérable. Il n'y a pas de voie diagnostique claire pour en déterminer la cause. Ainsi, les patients peuvent être hospitalisés et subir des tests diagnostiques coûteux, souvent répétés et non concluants. Les moniteurs cardiaques implantables existent depuis plus d'une décennie pour contribuer au diagnostic précoce des cas inexpliqués de syncope. Cependant, même s'il s'agit d'une invention canadienne, leur utilisation est sous-optimale dans le système de santé canadien. La présente étude donne un aperçu de la syncope et de sa prise en charge, ainsi que des économies potentielles par diagnostic si le moniteur cardiaque implantable était utilisé systématiquement en Ontario.
Alzheimer's disease biomarker discovery using SOMAscan multiplexed protein technology
Authors: Sattlecker Martina , Kiddle Steven J. , Newhouse Stephen , Proitsi Petroula , Nelson Sally , Williams Stephen , Johnston Caroline , Killick Richard , Simmons Andrew , Westman Eric , Hodges Angela , Soininen Hilkka , Kłoszewska Iwona , Mecocci Patrizia , Tsolaki Magda , Vellas Bruno , Lovestone Simon ,   AddNeuroMed Consortium, Dobson Richard J.B.
Published: April 2014

Blood proteins and their complexes have become the focus of a great deal of interest in the context of their potential as biomarkers of Alzheimer's disease (AD). We used a SOMAscan assay for quantifying 1001 proteins in blood samples from 331 AD, 211 controls, and 149 mild cognitive impaired (MCI) subjects. The strongest associations of protein levels with AD outcomes were prostate‐specific antigen complexed to α1‐antichymotrypsin (AD diagnosis), pancreatic prohormone (AD diagnosis, left entorhinal cortex atrophy, and left hippocampus atrophy), clusterin (rate of cognitive decline), and fetuin B (left entorhinal atrophy). Multivariate analysis found that a subset of 13 proteins predicted AD with an accuracy of area under the curve of 0.70. Our replication of previous findings provides further evidence that levels of these proteins in plasma are truly associated with AD. The newly identified proteins could be potential biomarkers and are worthy of further investigation.
Attitudes of Principals Towards Students With Disruptive Behaviour: An Australian Perspective
Authors: Wood Paul , Evans David , Spandagou Ilektra
Published: April 2014

This paper reports on the attitudes of 340 government primary principals from New South Wales, Australia, towards the inclusion of students with disruptive behaviours in schools. Principals’ attitudes were examined using the Principals and Behaviour Survey (PABS), a new composite measure built upon a foundation of existing validated surveys on attitudes towards the inclusion of students with disabilities. Principal component analysis identified 3 components that were used as variables for correlations with a range of demographic characteristics, such as age, qualifications, experience, school size and location. School size and the number of students with a diagnosed mental health condition in the school had a small relationship with principals’ attitudes. From the analysis of data from the emotional response scale, it was found that principals’ emotions about inclusion were less positive towards students with disruptive behaviour than towards students with sensory, physical or intellectual disabilities. Overall, principals appeared to hold dichotomous positions in regard to the benefits of inclusion, viewing it as beneficial for students with disruptive behaviour but not for their peers. However, principals who held more positive views were consistently more positive across all measures.
Artificial long days increase milk production in subtropical lactating goats managed under extensive grazing conditions
Authors: FLORES M. J. , DELGADILLO J. A. , FLORES J. A. , PASTOR F. J. , DUARTE G. , VIELMA J. , HERNÁNDEZ H.
Published: April 2014

The objective of the current study was to determine whether exposure to an artificial long-day photoperiod increases milk production in subtropical goats maintained under extensive grazing conditions, with or without the presence of a nutritional supplement. Forty-four lactating goats were exposed to a natural photoperiod (11 h light) with nutritional supplementation (NDS; natural day supplemented group; n=11) or without nutritional supplementation (NDN; natural day non-supplemented group; n=11) or to an artificial long-day photoperiod (16 h light) with nutritional supplementation (LDS; long-day supplemented group; n=11) or without nutritional supplementation (LDN; long-day non-supplemented group; n=11). Daily nutritional supplementation consisted of a mixture of 300 g rolled maize and 200 g soya bean per animal. During the suckling phase, milk yield was assessed at 10 and 20 days lactation and thereafter every 10 days up to 110 days lactation from day 40 of lactation. Plasma insulin-like growth factor 1 (IGF-I) concentration was determined at 20, 40, 60, 80 and 100 days of lactation. Mean milk yield was greater in goats from the LDN group than the NDN group. The difference in mean milk yield was greater when goats received a nutritional supplement. With nutritional supplementation, the plasma IGF-I concentrations were greater in goats exposed to long days than in those maintained under natural photoperiod. However, IGF-I concentrations were lower with long days when goats were not supplemented. In conclusion, exposure to an artificial long-day photoperiod increases milk yield in subtropical lactating goats maintained under extensive grazing conditions, and this increased milk production is more pronounced with a nutritional supplement. Furthermore, depending on nutritional status, exposure to artificial long days increases plasma IGF-I concentration in lactating goats.
In situswimming characteristics of the sea scallop,Placopecten magellanicus, on German Bank, Gulf of Maine
Authors: Mason Gwyn E. , Sameoto Jessica A. , Metaxas Anna
Published: April 2014

Size distribution and swimming activity of the sea scallop,Placopecten magellanicus, were measuredin situfrom high-definition video recordings collected by a remotely operated vehicle on a fished scallop bed on German Bank, Gulf of Maine in August 2010. Scallop densities ranged from 0.004 to 3.89 m−2and shell height (SH) ranged from 16.3 to 193.8 mm. The size distribution was bimodal, with high abundance from 20 to 40 mm SH indicating a recent recruitment event in the area. The low abundance of scallops >100 mm SH was likely due to the active fishery in this area. Of 535 observed swims, 200 were characterized for swim distance, time, velocity and distance travelled per adduction. The size of scallops observed to swim ranged from 18.9 to 99.9 mm SH. Both swim time and swim distance increased linearly with SH, and quadratic relationships were observed between velocity and SH, and between distance travelled per adduction and SH. Swimming velocities peaked at ~ 50 cm s−1for scallops between 60 and 80 mm, and maximum velocity was 103.2 cm s−1observed for an individual of 64.0 mm SH. Our study provided a unique opportunity to investigate size distribution and associated swimming activity of scallops in their natural habitat, rather than in a simulated study in the laboratory, and at depths not reachable by SCUBA diving.
A population-based longitudinal study of childhood neurodevelopmental disorders, IQ and subsequent risk of psychotic experiences in adolescence
Authors: Khandaker G. M. , Stochl J. , Zammit S. , Lewis G. , Jones P. B.
Published: April 2014

Background.

Schizophrenia has a neurodevelopmental component to its origin, and may share overlapping pathogenic mechanisms with childhood neurodevelopmental disorders (NDs). Nevertheless, longitudinal studies of psychotic outcomes among individuals with NDs are limited. We report a population-based prospective study of six common childhood NDs, subsequent neurocognitive performance and the risk of psychotic experiences (PEs) in early adolescence.

Method.

PEs were assessed by semi-structured interviews at age 13 years. IQ and working memory were measured between ages 9 and 11 years. The presence of six NDs (autism spectrum, dyslexia, dyspraxia, dysgraphia, dysorthographia, dyscalculia) was determined from parent-completed questionnaires at age 9 years. Linear regression calculated the mean difference in cognitive scores between children with and without NDs. Associations between NDs and PEs were expressed as odds ratios (ORs) with 95% confidence intervals (CIs); effects of cognitive deficits were examined. Potential confounders included age, gender, father's social class, ethnicity and maternal education.

Results.

Out of 8220 children, 487 (5.9%) were reported to have NDs at age 9 years. Children with, compared with those without, NDs performed worse on all cognitive measures; the adjusted mean difference in total IQ was 6.84 (95% CI 5.00–8.69). The association between total IQ and NDs was linear (p < 0.0001). The risk of PEs was higher in those with, compared with those without, NDs; the adjusted OR for definite PEs was 1.76 (95% CI 1.11–2.79). IQ (but not working memory) deficit partly explained this association.

Conclusions.

Higher risk of PEs in early adolescence among individuals with childhood ND is consistent with the neurodevelopmental hypothesis of schizophrenia.
Dimensionality and stages of severity of DSM-5 criteria in an international sample of alcohol-consuming individuals
Authors: Preuss U. W. , Watzke S. , Wurst F. M.
Published: April 2014

Introduction.

The DSM-5 alcohol use disorder (AUD) criteria proposal contains 11 criteria that include most of the DSM-IV abuse and dependence criteria plus craving. The aims of the current study in a large and international alcohol-consuming sample were to confirm the dimensionality of the DSM-5 AUD criteria and to differentiate grades of severity of DSM-5 AUD in subjects who pass the proposed DSM-5 diagnostic threshold of two criteria.

Method.

We used the World Health Organization (WHO)/International Society on Biomedical Research on Alcoholism (ISBRA) Study on State and Trait Markers of Alcohol Use and Dependence dataset. Subjects included in the analyses were aged ⩾18 years and were recruited in five countries: Australia, Brazil, Canada, Finland and Japan. Assessment of AUD and additional characteristics was conducted using an adapted version of the Alcohol Use Disorder and Associated Disabilities Interview Schedule (AUDADIS). Dimensionality of the DSM-5 criteria was evaluated using factor analysis and item response theory (IRT) models. The IRT results led to the classification of AUD patients into three severity groups. External validators were used to differentiate statistically across subgroups.

Results.

A total of 1424 currently drinking individuals were included in the analyses. Factor and IRT analyses confirmed the dimensional structure of DSM-5 AUD criteria. More than 99% of the subjects could be allocated to one of the suggested severity subgroups. The magnitude of the external validators differed significantly across the severity groups.

Conclusions.

The results confirm the dimensional structure of the proposed DSM-5 AUD criteria. The suggested stages of severity (mild, moderate and severe) may be useful to clinicians by grouping individuals not only in the mild but also in the moderate to severe spectrum of DSM-5 AUD.
Co-occurrence of psychotic experiences and common mental health conditions across four racially and ethnically diverse population samples
Authors: DeVylder J. E. , Burnette D. , Yang L. H.
Published: April 2014

Background.

Prior research with racially/ethnically homogeneous samples has demonstrated widespread co-occurrence of psychotic experiences (PEs) and common mental health conditions, particularly multi-morbidity, suggesting that psychosis may be related to the overall severity of psychiatric disorder rather than any specific subtype. In this study we aimed to examine whether PEs are associated with the presence of specific disorders or multi-morbidity of co-occurring disorders across four large racially/ethnically diverse samples of adults in the USA.

Method.

Data were drawn from the National Comorbidity Survey Replication (NCS-R), the National Survey of American Life (NSAL) and separately from the Asian and Latino subsamples of the National Latino and Asian American Study (NLAAS). Logistic regression models were used to examine the relationship between PEs and individual subtypes of DSM-IV disorder, and to test for a linear dose–response relationship between the number of subtypes and PEs.

Results.

Prevalence of PEs was moderately greater among individuals with each subtype of disorder in each data set [odds ratios (ORs) 1.8–3.8], although associations were only variably significant when controlling for clinical and demographic variables. However, the sum of disorder subtypes was related to odds for PEs in a linear dose–response fashion across all four samples.

Conclusions.

PEs are related primarily to the extent or severity of psychiatric illness, as indicated by the presence of multiple psychiatric disorders, rather than to any particular subtype of disorder in these data. This relationship applies to the general population and across diverse racial/ethnic groups.
Deep brain stimulation for obsessive–compulsive disorder: a systematic review and meta-analysis
Authors: Kisely S. , Hall K. , Siskind D. , Frater J. , Olson S. , Crompton D.
Published: April 2014

Background.

Deep brain stimulation (DBS) is increasingly being applied to psychiatric conditions such as obsessive–compulsive disorder (OCD), major depression and anorexia nervosa. Double-blind, randomized controlled trials (RCTs) of active versus sham treatment have been limited to small numbers. We therefore undertook a systematic review and meta-analysis of the effectiveness of DBS in psychiatric conditions to maximize study power.

Method.

We conducted a systematic literature search for double-blind, RCTs of active versus sham treatment using Pubmed/Medline and EMBASE up to April 2013. Where possible, we combined results from studies in a meta-analysis. We assessed differences in final values between the active and sham treatments for parallel-group studies and compared changes from baseline score for cross-over designs.

Results.

Inclusion criteria were met by five studies, all of which were of OCD. Forty-four subjects provided data for the meta-analysis. The main outcome was a reduction in obsessive symptoms as measured by the Yale–Brown Obsessive Compulsive Scale (YBOCS). Patients on active, as opposed to sham, treatment had a significantly lower mean score [mean difference (MD) −8.93, 95% confidence interval (CI) −13.35 to −5.76, p < 0.001], representing partial remission. However, one-third of patients experienced significant adverse effects (n = 16). There were no differences between the two groups in terms of other outcomes.

Conclusions.

DBS may show promise for treatment-resistant OCD but there are insufficient randomized controlled data for other psychiatric conditions. DBS remains an experimental treatment in adults for severe, medically refractory conditions until further data are available.
Adaptive source search in a gradient field
Authors: Zhang Xiaochen , Sun Yi , Xiao Jizhong
Published: April 2014

Most existing source search algorithms suffer from a high travel cost, and few of them have been analyzed in performance in noisy environments where local basins are presented. In this paper, the theseus gradient search (TGS) is proposed to effectively overcome local basins in search. Analytical performances of TGS and the gradient ascend with correlated random walk (GACRW), which is a variant of correlated random walk, are derived and compared. A gradient field model is proposed as an analytical tool that makes it feasible to analyze the performances. The analytical average searching costs of GACRW and TGS are obtained for the first time for this class of algorithms in the environments with local basins. The costs, expressed as functions of searching space size, local basin size, and local basin number are confirmed by simulation results. The performances of GACRW, TGS, and two chemotaxis algorithms are compared in the gradient field and a scenario of indoor radio source search in a hallway driven by real data of signal strengths. The results illustrate that GACRW and TGS are robust to noisy gradients and are more competitive than the chemotaxis-based algorithms in real applications. Both analytical and simulation results indicate that in the presence of local basins, TGS almost always costs the lowest.
Active global localization based on localizability for mobile robots
Authors: Wang Yong , Chen Weidong , Wang Jingchuan , Wang Hesheng
Published: April 2014

In global localization under the framework of a particle filter, the acquiring of effective observations of the whole particle system will be greatly effected by the uncertainty of a prior-map, such as unspecific structures and noises. In this study, taking the uncertainty of the prior-map into account, a localizability-based action selection mechanism for mobile robots is proposed to accelerate the convergence of global localization. Localizability is defined to evaluate the observations according to the prior-map (probabilistic grid map) and observation (laser range-finder) models based on the Cramér-Rao Bound. The evaluation considers the uncertainty of the prior-map and does not need to extract any specific observation features. Essentially, localizability is the determinant of the inverse covariance matrix for localization. Specifically, at the beginning of every filtering step, the action, which makes the whole particle system to achieve the maximum localizability distinctness, is selected as the actual action. Then there will be the increased opportunities for accelerating the convergence of the particles, especially in the face of the prior-map with uncertainty. Additionally, the computational complexity of the proposed algorithm does not increase significantly, as the localizability is pre-cached off-line. In simulations, the proposed active algorithm is compared with the passive algorithm (i.e. global localization with the random robot actions) in environments with different degrees of uncertainty. In experiments, the effectiveness of the localizability is verified and then the comparative experiments are conducted based on an intelligent wheelchair platform in a real environment. Finally, the experimental results are compared and analyzed among the existing active algorithms. The results demonstrate that the proposed algorithm could accelerate the convergence of global localization and enhance the robustness against the system ambiguities, thereby reducing the failure probability of the convergence.