bluuebunny/crossref_metadata_2025 huggingface dataset:
Impaired Auxin Biosynthesis in the defective endosperm18 Mutant Is Due to Mutational Loss of Expression in the ZmYuc1 Gene Encoding Endosperm-Specific YUCCA1 Protein in Maize
Authors: Bernardi Jamila , Lanubile Alessandra , Li Qin-Bao , Kumar Dibyendu , Kladnik Ale¡ , Cook Sam D. , Ross John J. , Marocco Adriano , Chourey Prem S.
Published: September 2012

The phytohormone auxin (indole-3-acetic acid [IAA]) plays a fundamental role in vegetative and reproductive plant development. Here, we characterized a seed-specific viable maize (Zea mays) mutant, defective endosperm18 (de18) that is impaired in IAA biosynthesis. de18 endosperm showed large reductions of free IAA levels and is known to have approximately 40% less dry mass, compared with De18. Cellular analyses showed lower total cell number, smaller cell volume, and reduced level of endoreduplication in the mutant endosperm. Gene expression analyses of seed-specific tryptophan-dependent IAA pathway genes, maize Yucca1 (ZmYuc1), and two tryptophan-aminotransferase co-orthologs were performed to understand the molecular basis of the IAA deficiency in the mutant. Temporally, all three genes showed high expression coincident with high IAA levels; however, only ZmYuc1 correlated with the reduced IAA levels in the mutant throughout endosperm development. Furthermore, sequence analyses of ZmYuc1 complementary DNA and genomic clones revealed many changes specific to the mutant, including a 2-bp insertion that generated a premature stop codon and a truncated YUC1 protein of 212 amino acids, compared with the 400 amino acids in the De18. The putative, approximately 1.5-kb, Yuc1 promoter region also showed many rearrangements, including a 151-bp deletion in the mutant. Our concurrent high-density mapping and annotation studies of chromosome 10, contig 395, showed that the De18 locus was tightly linked to the gene ZmYuc1. Collectively, the data suggest that the molecular changes in the ZmYuc1 gene encoding the YUC1 protein are the causal basis of impairment in a critical step in IAA biosynthesis, essential for normal endosperm development in maize.
DNA barcodes identify marine fishes of São Paulo State, Brazil
Authors: Ribeiro Amanda de Oliveira , Caires Rodrigo Antunes , Mariguela Tatiane Casagrande , Pereira Luiz Henrique Garcia , Hanner Robert , Oliveira Claudio
Published: September 2012

Anthropogenic impacts are an increasing threat to the diversity of fishes, especially in areas around large urban centres, and many effective conservation actions depend on accurate species identification. Considering the utility of DNA barcoding as a global system for species identification and discovery, this study aims to assemble a DNA barcode reference sequence library for marine fishes from the coastal region of São Paulo State, Brazil. The standard 652 bp ‘barcode’ fragment of the cytochrome c oxidase subunit I (COI) gene was PCR amplified and bidirectionally sequenced from 678 individuals belonging to 135 species. A neighbour‐joining analysis revealed that this approach can unambiguously discriminate 97% of the species surveyed. Most species exhibited low intraspecific genetic distances (0.31%), about 43‐fold less than the distance among species within a genus. Four species showed higher intraspecific divergences ranging from 2.2% to 7.6%, suggesting overlooked diversity. Notably, just one species‐pair exhibited barcode divergences of <1%. This library is a first step to better know the molecular diversity of marine fish species from São Paulo, providing a basis for further studies of this fauna – extending the ability to identify these species from all life stages and even fragmentary remains, setting the stage for a better understanding of interactions among species, calibrating the estimations about species composition and richness in an ecosystem, and providing tools for authenticating bioproducts and monitoring illegal species exploitation.
DPP‐4 Inhibition Attenuates Cardiac Dysfunction and Adverse Remodeling Following Myocardial Infarction in Rats with Experimental Diabetes
Authors: Connelly Kim Alexander , Zhang Yanling , Advani Andrew , Advani Suzanne L. , Thai Kerri , Yuen Darren A. , Gilbert Richard E.
Published: September 2012

Aims

Following myocardial infarction (MI), individuals with diabetes have a two‐fold increase in the risk of heart failure, due in part to excessive loss of cardiac microvasculature. Endothelial integrity and restitution are mediated in part by stromal cell–derived factor‐1α (SDF‐1α), a chemokine that is elaborated by ischemic tissue but rapidly degraded by dipeptidyl peptidase‐4 (DPP‐4). Accordingly, we hypothesized that inhibiting this enzyme may confer benefit following myocardial infarction in the diabetic setting beyond its effect on glycemia.

Methods and Results

Fischer F344 rats with streptozotocin (STZ)‐diabetes were randomized to receive vehicle or the DPP‐4 inhibitor, sitagliptin (300 mg/kg/day). Two weeks later, animals underwent experimental MI, induced by ligation of the left anterior descending coronary artery. Cardiac function was assessed by conductance catheterization and echocardiography along with cardiac structure 4 weeks post‐MI. Following MI, untreated diabetic rats developed both systolic and diastolic cardiac dysfunction, in association with endothelial cell loss, fibrosis, and myocyte hypertrophy. Without affecting plasma glucose, sitagliptin treatment led to an improvement in passive left ventricular compliance, increased endothelial cell density, reduced myocyte hypertrophy, and a reduction in the abundance of collagen 1 (all P < 0.05). Systolic function was unchanged.

Conclusions

This study shows that DPP‐4 inhibition attenuates several, but not all, aspects of cardiac dysfunction and adverse remodeling in the post‐MI setting.
The ecology of large carnivores in the highlands of northern Ethiopia
Authors: Yirga Gidey , De Iongh Hans H. , Leirs Herwig , Gebrehiwot Kindeya , Berhe Gebrehiwot , Asmelash Tsehaye , Gebrehiwot Haftu , Bauer Hans
Published: September 2012

The degradation and fragmentation of the northern Ethiopian highlands has resulted in frequent encounters of large carnivores with humans and their livestock. We interviewed 500 randomly selected households to estimate economic impact of livestock predation by spotted hyaena (Crocuta crocuta), leopard (Panthera pardus) and jackal (Canis aureus aureus) in the highlands of northern Ethiopia. The annual mean economic loss per household was approximately U.S.$ 20.2, about 7% of the average annual income of households in the area. Households surveyed reported losses of a total of 3122 livestock to hyaena, leopard and jackal predation over the past 5 years. This loss equated to a total financial loss of U.S.$ 50,381. Livestock predation incidents of spotted hyaena, leopard and jackal demonstrated that spotted hyaena had a preference for dog, donkey, goat and sheep; leopard for goat, dog and sheep; and jackal for goat and sheep. Livestock predation of spotted hyaena and leopard were mainly during the night. We conclude that assessing depredation problems is important to develop actions for management of either livestock practices or wildlife conservation.
How to dress as a paediatrician?
Authors: Hofmann Julia , Zotter Heinz , Kerbl Reinhold
Published: September 2012

Aim:  Do different clothing styles have an influence on the doctor–patient–parent relationship and which kind of outfit is preferred by children and parents.

Methods:  One hundred and seven children and 72 parents were visited by a paediatrician randomly wearing one of the three different outfits (casual, semiformal, formal) during a hospital stay. Parents and children between 6 and 18 years were then interviewed about their opinion by use of a semi‐structured questionnaire, while children between 0 and 6 years were observed concerning their behaviour during the examination.

Results:  Using a ‘likert scale’, the casual outfit received the best mark by 95.5% of parents (58.3% in the semiformal, 30.8% in the formal group). The degree of the parents’ trust in the paediatrician was comparable in all three groups. In children between 6 and 18 years, the casual dress was rated highest in 100%. In children between 0 and 6 years, the outfit had no significant influence on the patients’ behaviour.

Conclusion:  Apparently, parents do not only tolerate a casual outfit, but even prefer it without any loss of trust. The same holds true for children between 6 and 18 years. For younger children, the paediatricians’ outfit seems to play no major role.
Anthropometric estimates of total and regional body fat in children aged 6–17 years
Authors: Flavel Nicole A , Olds Timothy S , Buckley Jonathan D , Haren Matthew T , Petkov John
Published: September 2012

Aim:  To develop prediction equations for total and regional (trunk, abdominal, arms and legs) body fat using surface anthropometric measures in children aged 6–17 years.

Methods:  This was a cross‐sectional correlation study of 70 Caucasian children aged 6–17 years recruited from a larger randomly sampled population‐based study. The independent variables included age, mass, height, body mass index, waist and hip girth, and skinfold thicknesses at eight sites. Subscapular/triceps skinfold ratio was also calculated and entered as an independent variable. The dependent variables were total body percentage fat, and fat mass for total body, trunk, abdominal region of interest, arms and legs measured using dual‐energy X‐ray absorptiometry (DXA). Partial least squares regression was used to determine the best predictive equation for fat percentage or fat mass in each body region in each sex.

Results:  Sex‐specific prediction equations were developed with high coefficients of determination (r2), ranging from 0.869 to 0.936 in boys and from 0.900 to 0.979 in girls, absolute bias was low, and limits of agreement were narrow.

Conclusion:  Equations were developed, which were able to predict total and regional body fat of Caucasian children aged 6–17 years using surface anthropometric measurements with high predictive accuracy.
Dyspepsia is strongly associated with major depression and generalised anxiety disorder ‐ a community study
Authors: Mak A. D. P. , Wu J. C. Y. , Chan Y. , Chan F. K. L. , Sung J. J. Y. , Lee S.
Published: September 2012

Background

The relationship between dyspepsia and psychiatric comorbidity such as anxiety and depression is poorly defined. Previous studies have been limited by lack of standardised diagnostic criteria.

Aim

To examine the prevalence and comorbidity of dyspepsia as defined by Rome III (6‐month duration) with DSM‐IV‐TR generalised anxiety disorder (GAD) and major depressive episodes (MDE) in the general population.

Methods

A random population‐based telephone survey was done using a questionnaire on symptoms of Rome III Dyspepsia, DSM‐IV‐TR GAD and MDE and their chronological relationship.

Results

Of the 2011 respondents 8.0% currently had Rome III Dyspepsia, 3.8% reported GAD and 12.4% reported MDE respectively. Dyspeptic subjects had a twofold increased risk of GAD (OR = 2.03, 95% CI: 1.06–3.89, P < 0.001) and a threefold increased risk of MDE (OR = 3.56, 95% CI: 2.33–5.43, P < 0.001). MDE and GAD most often coincided with dyspepsia in onset. Dyspepsia (OR = 2.48, 95% CI: 1.65–3.72 P < 0.001), MDE (OR = 2.39, 95% CI: 1.64–3.46, P < 0.001) and female sex (OR = 1.65, 95% CI: 1.21–2.23, P < 0.001) independently predicted frequent medical consultations. GAD independently predicted high investigation expenditure (OR = 4.65, 95% CI: 1.15–18.70, P = 0.03).

Conclusions

With stringently adopted Rome III and DSM‐IV‐TR criteria, dyspepsia was strongly associated and often coincident in onset with generalised anxiety disorder and major depressive episodes in the community. Excessive healthcare utilisation should alert clinicians to risk of psychiatric comorbidity.
Never mind what I like, it's who I am that matters: an investigation into social pedagogy as a method to enhance the involvement of young people with learning disabilities
Authors: Carter Sid , Cameron Fergus , Houghton Jenny , Walton Michelle
Published: September 2012

Accessible summary

Children and young people with learning disabilities should be involved in decisions that affect them, including having a say in how their services are run.

In practice, it is difficult to achieve involvement, as service providers can treat young people with disabilities and their families as ‘shoppers’ rather than really listening to them. It can also be hard to find out exactly how individuals feel, because of their difficulties with language and complicated information.

Social pedagogy is an approach to working with children who sees them as equals. The study used these ideas to run a group to involve young people with learning disabilities who used short break services.

The research found that social pedagogy was a good way to improve involvement, as it helped to build trusting and equal relationships between young people with learning disabilities and the adults who worked with them.

The involvement of children and young people with learning disabilities in the decision‐making of the services they use is recognised as an essential principle. However, implementation of this principle has encountered two main obstacles. One obstacle is that meaningful involvement has largely been subsumed by a provider‐driven consumerist agenda. A second obstacle is the lack of methods to gain feedback that take account of an individual's cognitive and linguistic impairments. This article reports on the use of the social pedagogy approach to attempt to overcome these obstacles. The findings show that social pedagogy, which emphasises a balance between ‘head, heart and hands’, provided a means to establish egalitarian relationships with young people with learning disabilities. Thus, social pedagogy was found to be effective in enhancing involvement in the context of a person‐centred approach.
Impact of age, phenotype and cardio‐renal function on plasma C‐type and B‐type natriuretic peptide forms in an adult population
Authors: Prickett T. C. R. , Olney R. C. , Cameron V. A. , Ellis M. J. , Richards A. M. , Espiner E. A.
Published: September 2012

Context

In contrast to the cardiac hormones, atrial natriuretic peptide (ANP) and B‐type natriuretic peptide (BNP), variations in plasma concentrations of C‐type natriuretic peptide (CNP) in healthy adults are ill‐defined, limiting their clinical application.

Objective

Our objective was to define the effect of age, phenotype (gender, height, BMI), and cardiac and renal function on plasma CNPs in an adults population without renal or cardiovascular disease.

Design and setting

This was a prospective cross‐sectional observational study of adult volunteers, aged 21–80 years, randomly selected from the electoral roll.

Subjects and methods

Plasma CNP and its associated aminoterminal propeptide (NTproCNP) were measured in 258 subjects and related to age, gender, height and plasma creatinine. Subgroup analyses seeking associations with cardiac function (plasma BNP and NTproBNP) and bone turnover bone‐specific alkaline phosphatase (bALP) were also determined.

Results

Plasma concentrations of CNPs in men continued to decline from adolescent values to reach a nadir in the 5th decade after which values increased. Similar but less marked changes occurred in women. In both sexes, NTproCNP was inversely and independently correlated with height. In contrast to B‐type natriuretic peptides (BNPs), NTproCNP was higher in men, significantly related to creatinine and positively related to bALP.

Conclusions

Gender‐ and age‐specific changes affect CNPs in adults. Inverse associations of NTproCNP with adult height, positive correlation with creatinine – and in contrast to CNP – no association with BNP are further unique findings distinguishing NTproCNP, which need to be considered in future studies.
Rate of Change in Physical Fitness and Quality of Life and Depression Following Exercise Training in Patients With Congestive Heart Failure
Authors: Smart Neil A. , Murison Robert
Published: September 2012

©2012 Wiley Periodicals, inc.

Exercise training appears to improve peak oxygen consumption (VO2) and quality of life (QOL) in heart failure patients, although disease etiology, patient demographics and medication may alter the rate of adaptation. The authors sought to identify rate of change from baseline in fitness, QOL, and depression following exercise training in a cohort of patients with congestive heart failure. Thirty male systolic heart failure patients (aged 63.8±8.3 years, baseline peak VO2 12.2±4.8 mL/kg/min, left ventricular ejection fraction 28.2±9.4%, New York Heart Association class II/II 22/8) undertook 52 weeks of exercise training, 16 weeks as an outpatient and a further 36 weeks of home exercise. Peak VO2 and QOL was measured using the Minnesota Living With Heart Failure (MLWHF) questionnaire and depression using the Hare‐Davis scale. The authors analyzed the rate of change in peak VO2 and MLWHF after grouping patients according to clinical, demographic, and pharmacologic characteristics. Peak VO2 measurements varied over time, with no effect of disease pathology or β‐blocker on peak VO2. The rate of change in physical MLWHF score was significantly greater (improved) during 0 to 16 weeks in patients with dilated pathology, but was not significantly affected by β‐blocker use or age. The exercise training venue and supervision, or lack thereof, is the major determinant of adaptation to the intervention in heart failure patients, although age, β‐adrenergic medication, and heart failure etiology also explain some of the variation in adaptive responses observed.
Relationship of Cardiac Magnetic Resonance Imaging and Myocardial Biopsy in the Evaluation of Nonischemic Cardiomyopathy
Authors: Dickerson Jennifer A. , Raman Subha V. , Baker Peter M. , Leier Carl V.
Published: September 2012

©2012 Wiley Periodicals, inc.

This study was performed to determine the relative role of cardiac magnetic resonance (CMR) imaging and endomyocardial biopsy (EMB) in the evaluation of cardiomyopathy. Sixty‐six patients with a clinical diagnosis of nonischemic dilated cardiomyopathy or restrictive cardiomyopathy underwent both EMB and CMR imaging as part of their diagnostic evaluation. The authors retrospectively reviewed the results of these two methods to determine their diagnostic impact and congruency. CMR imaging provided data on cardiac anatomy, left ventricular volumes, mass, and function in 85% of the patients, uncovered fibrosis in 31%, myocardial ischemia in 7%, and fibrofatty infiltration in two patients. EMB provided the histologic findings of cardiomyocyte hypertrophy in 77% of patients and substantial interstitial fibrosis in 59%. Six patients had EMB‐proven amyloid heart disease, which was detected by CMR imaging in two. CMR imaging showed patterns of late gadolinium enhancement supportive of infiltrative disease or inflammation in 6 patients with EMB‐proven definite (n=3) or borderline (n=3) myocarditis, but failed to do so in two other patients with borderline and two with resolving myocarditis. At the present time, CMR imaging and EMB remain complementary procedures in the evaluation of cardiomyopathic conditions.
Estimating migratory fish distribution from altitude and basin area: a case study in a large Neotropical river
Authors: BARRADAS JOSÉ RICARDO S. , SILVA LUCAS G. , HARVEY BRET C. , FONTOURA NELSON F.
Published: September 2012

1. The objective of this study was to identify longitudinal distribution patterns of large migratory fish species in the Uruguay River basin, southern Brazil, and construct statistical distribution models for Salminus brasiliensis, Prochilodus lineatus, Leporinus obtusidens and Pseudoplatystoma corruscans.

2. The sampling programme resulted in 202 interviews with old residents and fishermen at 167 different sampling sites in the major rivers of the basin. Interviewees were asked whether these fish species were present in the nearby river segment, recently or in the past. The average age of respondents was 56 years, and the great majority had resided for more than 30 years in the area where they were interviewed.

3. Fish distribution patterns were modelled using altitude and basin area as environmental descriptors. Distributional patterns were estimated using logistic equations (LOGIT): , where Al is the altitude and BA is the basin area.

4. Accuracies of the distribution models were between 77 and 85%. These accuracies are similar to those of published distribution models for other fishes based on larger numbers of environmental descriptors.

5. The historical distributional ranges make clear that all operating or planned large hydropower dams in the Uruguay River basin, with one exception, limit or will limit the distribution of migratory fishes.
Cutaneous findings in children with intellectual disabilities
Authors: Schepis Carmelo
Published: September 2012

The link between pediatric dermatology and intellectual disabilities (ID) is revised, according to the author's personal experience and the existing published work. Cutaneous manifestations in children with ID can be: (i) a key element to reach a diagnosis, as in neurodermatoses; (ii) a peculiar sign to define a complex syndrome; (iii) linked to behavioral features; (iv) iatrogenic, caused by drugs, as a side‐effect; and (v) independent from ID.
Pediatric case report: Clinical profile of a patient with PCWH with p.Q377X nonsense mutation in the SOX10 gene
Authors: Oshimo Tomoko , Fukai Kazuyoshi , Abe Yuko , Hozumi Yutaka , Yokoi Toshiaki , Tanaka Akemi , Yamanishi Kiyofumi , Ishii Masamitsu , Suzuki Tamio
Published: September 2012

We report the case of a Japanese patient with PCWH, a neurological variant of Waardenburg type 4. Direct sequencing of the genomic DNA obtained from peripheral leukocytes revealed the p.Q377X nonsense mutation in the SOX10 gene. The patient had mottled hypopigmented macules on the trunk since birth; such macules have not been described previously. The so‐called “white forelock”, a triangular or diamond shaped leukoderma on the forehead, was absent. We also reviewed and summarized the outcomes of 23 patients with Waardenburg syndrome type 4, PCWH and Yemenite deaf–blind hypopigmentation syndrome, in which SOX10 mutations were identified. Among them, 17 cases were reported to have hypopigmented skin macule(s). The five patients who had the white forelock had PCWH with severe neurological complications. Paradoxically, two cases had hyperpigmented spots. Heterochromia of the iris was reported in four patients.
Mineralogical composition of sediment determines the preference for smooth particles by caddisfly larvae during case construction
Authors: OKANO JUN‐ICHI , KIKUCHI EISUKE , SASAKI OSAMU , OHI SHUGO
Published: September 2012

1. The mineralogical/petrological composition of the substratum influences aquatic organisms in several ways. However, the actual mechanisms are often unclear. Some caddisfly larvae actively concentrate smooth quartz particles in their portable cases thus producing a smooth inner surface of the case wall.

2. The particle surface‐roughness preference of Perissoneura paradoxa (Odontoceridae) McLachlan inhabiting granite areas in relation to the mineral composition and surface roughness of sediment particles was examined.

3. Field surveys revealed that quartz was consistently smoother than other minerals but that it became rougher in larger size fractions, and the relative abundance of quartz decreased in larger size fractions. Consequently, smooth particles were less abundant in larger size fractions of the sediment. When larval cases were compared with sediment, quartz was actively concentrated in smaller cases of early instar larvae but was gradually less abundant in larger cases of well‐grown larvae. Because larvae use larger particles as they grow, late instar larvae develop an unselective choice of mineral types.

4. Subsequently, we experimentally forced the larvae to choose from a mixture of equal amounts of two artificial particles that had different textures (rough and smooth). The proportion of smooth particles chosen by larvae gradually decreased as they grew larger.

5. These results indicate that the larvae varied in their degree of preference according to particle availability in the surrounding sediment, which is governed by mineral composition and weatherability. We suggest that case‐bearing caddisfly can adapt to the local sediment environments by varying their standard and/or criteria for material choice. In this study, the possible mechanism for the variation is discussed.
Sterile stockinette in orthopaedic surgery: a possible pathway for infection
Authors: Boekel Pamela , Blackshaw Rachel , Van Bavel Dirk , Riazi Arash , Hau Raphael
Published: September 2012

Background

The prevention of infection in joint replacement surgery is important. Preparing and draping the patient is fundamental to maintaining sterility of the operative field. One method of draping for total knee replacement (TKR) surgery involves cleaning the operative leg with antiseptic wash then covering the un‐prepped foot with a sterile stockinette to sequester the foot from the sterile field. There are two main methods for applying this stockinette. This randomized, blinded control trial simulates stockinette application to assess if it prevents proximal microbial migration into the sterile field.

Method

To simulate microbial presence, ultraviolet fluorescent powder Glitterbug PowderTM (Arrow Scientific Pty Ltd, Lane Cove, NSW, Australia) was applied to volunteers' feet to the level where antiseptic wash would routinely stop during preparation. The stockinette was applied. Two methods of application (above and below knee) and two surgeons were used. These were randomized for each application. The drapes were removed and a blinded assistant measured the distance of proximal spread of Glitterbug PowderTM.

Results

Both methods of application were associated with considerable proximal spread of Glitterbug PowderTM. For the below knee method, mean proximal spread distance of 49.19%; for the above knee, mean of 71.8% proximal spread (P = 0.038). Multivariate linear regression analysis demonstrated that method and location of the contamination were predictive of the area of contamination and the percentage of the leg contaminated. No other factors (surgeon, gender, hirsute score) were predictive of either area or percentage contamination.

Conclusion

The surgical field for TKRs may be contaminated by significant proximal microbial spread from the unprepared foot with the use of a sterile stockinette drape.
Multi‐site videoconference tutorials for medical students in Australia
Authors: Smith Anthony C. , White Megan M. , McBride Craig A. , Kimble Roy M. , Armfield Nigel R. , Ware Robert S. , Coulthard Mark G.
Published: September 2012

Background

About two‐thirds of medical students are distributed among the major metropolitan tertiary teaching hospitals in Queensland, while the remainder are sent to regional hospitals up to 500 km away. The aim of this study was to investigate the feasibility and effectiveness of conducting surgical tutorials via videoconferencing (VC) for medical students undertaking at remote hospitals.

Methods

Surgical tutorials were offered to final‐year medical students at the Royal Children's Hospital (RCH) in Brisbane and shared by VC to students undertaking clinical placement at nine remotely located hospitals in Queensland. We have conducted a retrospective review of service activity, student satisfaction and subject scores from 2008 to 2010. The main outcome measures were VC activity, medical students' satisfaction and student exam results pre‐ and post‐introduction of the surgical tutorial programme.

Results

Between March 2009 and November 2010, a total of 57 VC tutorials were conducted during nine rotations for a total of 669 students. Approximately, 35% of students (236) attended tutorials face‐to‐face at the RCH while the remainder (including those at the Mater Children's Hospital in Brisbane and eight regional sites) participated via VC. A snapshot survey to measure satisfaction of both groups of students showed that overall satisfaction was very high. A total of 299 students completed the paediatrics and child health multiple‐station assessment task exam in 2008, 326 in 2009 and 382 in 2010. The pre‐intervention (tutorials not delivered by VC) median scores (interquartile range) of surgical and non‐surgical questions were 5 (4–6) and 23 (21–25). Post‐intervention, surgical scores increased significantly to 6 (5–7) (P < 0.001), while non‐surgical scores remained similar at 23 (21–25) (P = 0.64).

Conclusions

Our study demonstrates that VC is a feasible and effective method of engaging medical students regardless of their location. VC provides equitable access to medical teaching for medical students undertaking remote clinical placements.
Total joint replacement in men: old age, obesity and in‐hospital complications
Authors: Mnatzaganian George , Ryan Philip , Norman Paul E. , Davidson David C. , Hiller Janet E.
Published: September 2012

Background

We assessed risks of incident in‐hospital complications and 1‐year and 5‐year mortality following elective primary total joint replacement (TJR), focusing on obesity.

Methods

Longitudinal data from a population‐based cohort of 819 men who had had TJR were integrated with validated hospital morbidity data and mortality records. Complications recorded in the index admission were classified as major or minor by 13 independent orthopaedic surgeons.

Results

Of 819 men (mean age 76.3 (SD 4.5) years), 331 patients (40.4%) had an in‐hospital complication from whom 155 (18.9%) had at least one major complication that was classified as potentially life threatening. Obesity and age were independently associated with increased risk of major complications. Compared with patients without complications, those with major complications experienced significantly greater mortality in 1 year (5.8% versus 1.2%, P = 0.001) and 5 years (16.8% versus 8.0%, P = 0.002) following TJR. In Cox regressions, age, Charlson Co‐morbidity index and major complications were independently associated with 1‐year mortality. Age and Charlson Co‐morbidity index were also associated with 5‐year mortality. Similarly, risk of dying within 5 years of TJR was higher among patients with class II obesity compared with patients with normal weight. The most frequently reported complications were those in the cardio‐respiratory and general systems. Complications in the cardio‐respiratory system significantly increased hazard of 1‐ and 5‐year mortality.

Conclusion

The elderly and the obese are more likely to develop adverse outcomes following a primary TJR. Our findings may assist clinicians in better selecting elderly patients for surgery, and informing them about their individual level of risk.
Different approaches to volume assessment of lymph nodes in computer tomography scans of head and neck squamous cell carcinoma in comparison with a real gold standard
Authors: Mueller Stefan , Wichmann Gunnar , Dornheim Lars , Roessling Ivo , Bertolini Julia , Preim Bernhard , Dietz Andreas , Boehm Andreas
Published: September 2012

Background

Volume assessment in head and neck squamous cell carcinoma (HNSCC) is becoming a more and more clinical important parameter, especially in treatment planning and response control. Various authors showed a significant impact of tumour volume on treatment outcome and local control. Regarding the increasing impact of induction chemotherapy and primary chemoradiation on HNSCC, the need for an adequate measuring tool to judge treatment response becomes obvious. This study was performed to compare the momentary ‘gold standard’, the diameter‐based approach, and tumour volume assessment in HNSCC with approaches based on segmentation algorithms in computer tomography (CT) scans.

Methods

CT scans were taken as part of the standardized staging investigations. Using these image data, 30 lymph nodes were defined and segmented. The segmentations were carried out with the newly developed software called ‘NeckSegmenter’. After obtaining informed consent from the patient, neck dissection was performed and the excised lymph nodes underwent analysis of their true volume. The datasets were compared with each other and put in correlation with the segmented volumes.

Results

Pearson's correlation index showed a higher correlation of the segmented volumes (r = 0.7979) with the true volumes than the results generated via diameter‐based equation (r = 0.7974). Furthermore, the diameter‐generated volumes show clearly too high volumes at 130% (confidence interval: 107.7–156.7%). The volumes generated with the segmentation are at 89.18% (confidence interval: 73.52–108.16%).

Conclusion

The data show a higher reliability for volumes estimated by the segmentation‐based approach than the widely used diameter‐based approach.
The place of volition in addiction: Differing approaches and their implications for policy and service provision
Authors: Karasaki Mutsumi , Fraser Suzanne , Moore David , Dietze Paul
Published: September 2012

Introduction.

‘Addiction’ is an ambiguous concept. Its meaning, and how it is used in drug policy and treatment, depends on how it is conceptualised. While the ‘disease’ model of addiction is prevalent in Australia, differing, sometimes contradictory, interpretations of this model are mobilised.

Methods.

Drawing on 20 semi‐structured interviews conducted with professionals working in the area of drug use in Victoria, Australia, this paper develops a typology delineating different approaches to addiction.

Results.

Five domains of meaning related to addiction were identified in the data. These were: (i) the sign of craving; (ii) susceptibility; (iii) social and psychological issues producing addiction; (iv) self‐concept; and (v) social functions of addiction. These domains are further divided into two subtypes based on how the participants understood the role of a key notion in addiction: volition, that is, whether or not an ‘addict’ has control over drug use and other aspects of life.

Discussion.

By systematically mapping different conceptualisations of addiction, this typology identifies the ambiguities and contradictions in the models currently in use, especially with respect to the notion of volition. While a homogeneous approach to these issues is neither practical nor desirable, there is a need to consider the implications of this lack of coherence.

Conclusions.

Service providers, medical practitioners and policy makers need to reflect on their assumptions, and consider the implications of their different approaches for clients, some of whom encounter more than one approach when undergoing treatment for drug use.
Toddlers’ Processing of Phonological Alternations: Early Compensation for Assimilation in English and French
Authors: Skoruppa Katrin , Mani Nivedita , Peperkamp Sharon
Published: September 2012

Using a picture pointing task, this study examines toddlers’ processing of phonological alternations that trigger sound changes in connected speech. Three experiments investigate whether 2;5‐ to 3‐year‐old children take into account assimilations—processes by which phonological features of one sound spread to adjacent sounds—for the purpose of word recognition (e.g., in English, ten pounds can be produced as te[mp]ounds). English toddlers (n = 18) show sensitivity to native place assimilations during lexical access in Experiment 1. Likewise, French toddlers (n = 27) compensate for French voicing assimilations in Experiment 2. However, French toddlers (n = 27) do not take into account a hypothetical non‐native place assimilation rule in Experiment 3, suggesting that compensation for assimilation is already language specific.
Wage and Productivity Differentials in Japan: The Role of Labor Market Mechanisms
Authors: Kalantzis Yannick , Kambayashi Ryo , Lechevalier Sébastien
Published: September 2012

This paper aims at explaining two stylized facts of the Lost Decade in Japan: rising wage inequalities and increasing firm‐level productivity differentials. We build a model where firms can choose between efficiency wages with endogenous effort and competitive wages, and show that it can replicate those facts. Using Japanese microeconomic data, we find support for the existence of efficiency wages in one group of firms and competitive wages in the other group. Based on those results, a simulation shows that the share of firms using efficiency wages has declined, within sectors, during the Lost Decade, as predicted by the model.
The Effects of Personality Traits on Wages: A Matching Approach
Authors: Girtz Robert
Published: September 2012

I use the National Longitudinal Survey of Youth 1979 to estimate the effects of adolescent measurements of self‐esteem and locus of control on adult wages using propensity score matching. An adolescent possessing high self‐esteem will experience between 8.5 and 9.2 per cent higher wages as an adult. This result is statistically significant and robust to the addition of cognitive skill and family background characteristics. When cognitive skill and family background characteristics are controlled for, locus of control as an adolescent is insignificant in explaining adult wages. This result is contrary to findings in the literature.
Acquiring Noun Plurals in Palestinian Arabic: Morphology, Familiarity, and Pattern Frequency
Authors: Saiegh‐Haddad Elinor , Hadieh Areen , Ravid Dorit
Published: September 2012

The study examined the acquisition of two morphological procedures of noun pluralization in Palestinian Arabic: Sound Feminine Plural (SFP) and Broken Plural (BP). We tested if noun pluralization was affected by (1) the type of morphological procedure, (2) the degree of familiarity with the singular noun stem, and (3) the frequency of plural patterns. Thirty‐six native Arabic‐speaking children in three age groups were tested on three experimental tasks: a repetition task, a structured production task, and a seminatural production task. In line with earlier research, the results showed that SFP pluralization was acquired earlier and had a shorter developmental trajectory than BP plurals. Also, the errors of children showed that SFP was a dominant default procedure. However, despite its early consolidation, SFP formation was affected by familiarity with the singular noun stem. BP nouns also appeared rather early in the production of children and were affected by both familiarity with the noun stem and frequency of the plural pattern. Yet, they took longer to acquire and did not reach comparable levels to SFP in the age groups tested. The implications of the results for models of language acquisition and the acquisition of Arabic morphology are discussed.
Reluctant ‘Jailors’ speak out: parents of adults with Down syndrome living in the parental home on how they negotiate the tension between empowering and protecting their intellectually disabled sons and daughters
Authors: Foley Simon
Published: September 2012

Accessible summary

This study looks at the issue of the social lives of adults with Down syndrome who are living at home with their parents.

Sometimes, for the very best of reasons, the parents of adults with Down syndrome try to prevent their adult son or daughter with Down syndrome from going out on their own, from having a boyfriend or a girlfriend etc.

In this study, I talk to a group of parents about how they feel when they think about the kind of social life their sons and daughters with Down syndrome have.

For example, I ask them are they happy with the amount of friends that their son or daughter has, whether their son or daughter has a boyfriend or girlfriend, whether they would like to see their son or daughter get married etc.

Because of the role played by parents in the social lives of their intellectually disabled adult son or daughter, it is very important for everybody concerned with the quality of life enjoyed by adults with an intellectual disability to understand why their parents think and act the way they do.

While the language of empowerment and human rights have taken centre stage in both the disability literature and disability service provision for adults with intellectual disabilities. One area where there exists a disconnect between theory and practice, in the Republic of Ireland at any rate, lies in the parental home and the role played by parents of adults with intellectual disabilities (this study focuses specifically on adults with Down syndrome) in acting as gatekeepers of their son or daughters social life. For the best of paternalistic reasons, many parents of adults with Down syndrome severely restrict the life choices of their adult sons or daughters. This is particularly the case when it comes to the regulation of their son or daughters sexuality, a possible effect of which may be to effectively deprive their intellectually disabled son or daughter of the opportunity of ever entering into an intimate sexual relationship with another human being. So are parents of adults with Down syndrome actually playing the role of ‘reluctant jailors’? If yes, how do they navigate the enormously tricky terrain that characterises the Scylla and Charybdis like tension between trying to empower their adult son or daughter with Down syndrome while at the same time doing all they can to insure they come to no harm? This study interviews ten parents on the earlier issues, to gain a greater phenomenological understanding on the predicament that many parents of adults with Down syndrome believe themselves to be in.
Practitioner Review: What have we learnt about the causes of ADHD?
Authors: Thapar Anita , Cooper Miriam , Eyre Olga , Langley Kate
Published: September 2012

Background:  Attention deficit hyperactivity disorder (ADHD) and its possible causes still attract controversy. Genes, pre and perinatal risks, psychosocial factors and environmental toxins have all been considered as potential risk factors.

Method:  This review (focussing on literature published since 1997, selected from a search of PubMed) critically considers putative risk factors with a focus on genetics and selected environmental risks, examines their relationships with ADHD and discusses the likelihood that these risks are causal as well as some of the main implications.

Results:  No single risk factor explains ADHD. Both inherited and noninherited factors contribute and their effects are interdependent. ADHD is familial and heritable. Research into the inherited and molecular genetic contributions to ADHD suggest an important overlap with other neurodevelopmental problems, notably, autism spectrum disorders. Having a biological relative with ADHD, large, rare copy number variants, some small effect size candidate gene variants, extreme early adversity, pre and postnatal exposure to lead and low birth weight/prematurity have been most consistently found as risk factors, but none are yet known to be definitely causal. There is a large literature documenting associations between ADHD and a wide variety of putative environmental risks that can, at present, only be regarded as correlates. Findings from research designs that go beyond simply testing for association are beginning to contest the robustness of some environmental exposures previously thought to be ADHD risk factors.

Conclusions:  The genetic risks implicated in ADHD generally tend to have small effect sizes or be rare and often increase risk of many other types of psychopathology. Thus, they cannot be used for prediction, genetic testing or diagnostic purposes beyond what is predicted by a family history. There is a need to consider the possibility of parents and siblings being similarly affected and how this might impact on engagement with families, influence interventions and require integration with adult services. Genetic contributions to disorder do not necessarily mean that medications are the treatment of choice. We also consider how findings might influence the conceptualisation of ADHD, public health policy implications and why it is unhelpful and incorrect to dichotomise genetic/biological and environmental explanations. It is essential that practitioners can interpret genetic and aetiological research findings and impart informed explanations to families.
Do Insurance Companies Possess an Informational Monopoly? Empirical Evidence From Auto Insurance
Authors: Kofman Paul , Nini Gregory P.
Published: September 2012

ABSTRACT

This article investigates the impact of policyholder tenure on contractual relationships in nonlife insurance markets. For a sample of auto insurance policies, we find that average risk decreases with policyholder tenure, but the effect is entirely due to the impact of observable information. We reject the hypothesis that the incumbent insurer is privately learning faster about quality of their policyholders. We highlight the importance of a public signal regarding policyholders' claims experiences and suggest alternative explanations for the unconditional relationships in the data.
Pricing Survivor Derivatives With Cohort Mortality Dependence Under the Lee–Carter Framework
Authors: Wang Chou‐Wen , Yang Sharon S.
Published: September 2012

ABSTRACT

This article introduces cohort mortality dependence in mortality modeling. We extend the classical Lee–Carter model to incorporate cohort mortality dependence by considering mortality correlations for a cohort of people born in the same year. The pattern of cohort mortality dependence is demonstrated on the basis of U.S. mortality experience. We study the effect of cohort mortality dependence on the pricing of survivor derivatives. For this purpose, a survivor floor is introduced. To understand the difference between a survivor floor and other survivor securities, the valuation formulas for survivor swaps and survivor floors are all derived in detail and the effects of cohort mortality dependence on pricing survivor derivatives are investigated numerically.
Derivatives Clearing, Default Risk, and Insurance
Authors: Jones Robert A. , Pérignon Christophe
Published: September 2012

Abstract

Using daily data on margins and variation margins for all clearing members of the Chicago Mercantile Exchange, we analyze the clearing house exposure to the risk of default by clearing members. We find that the major source of default risk for a clearing member is proprietary trading rather than trading by customers. Additionally, we show that extreme losses suffered by important clearing firms tend to cluster, which raises systemic risk concerns. Finally, we discuss how private insurance could be used to cover the loss from defaults by clearing members.
In vitro study of effects of emulsified oil on broiler feed quality
Authors: Liu Xiao‐Chuan , Yang Zai‐Bin , Yang Wei‐Ren , Jiang Shu‐Zhen , Zhang Gui‐Guo
Published: September 2012

An experiment was conducted to compare effects of emulsified soybean oil and non‐emulsified soybean oil on the quality of broiler feed differing in the feed type and the broiler feeding stage in vitro. A 2 × 2 × 3 factorial arrangement was designed with two fat sources (soybean oil and emulsified oil), two feed types (mash and pellet) and three broiler feeding stages (starter, grower and finisher). Four samples of feeds were collected from each combination of factors at the beginning of the experiment and stored at 20°C. Subsamples were taken at 15‐day intervals to determine the moisture content, peroxide value (PV), acid value (AV) and the total fungal count over a 45‐day period; weight loss percentage was determined by weighting the samples at days 0, 15, 30 and 45; fines percentage in pellets was only determined at day 0. The emulsified oil reduced (P < 0.05) the fines percentage, increased (P < 0.05) the moisture content, decreased (P < 0.05) the weight loss percentage and PV, did not affect (P > 0.05) the AV and the total fungal count. Results showed that the emulsified oil decreased weight loss, increased pelletability, moisture content and oxidation stability without affecting fungal growth.