bluuebunny/crossref_metadata_2025 huggingface dataset:
Job satisfaction and intention to leave: a questionnaire survey of hospital nurses in Shanghai of China
Authors: Liu Cui , Zhang Lingjuan , Ye Wenqin , Zhu Jianying , Cao Jie , Lu Xiaoying , Li Fengping
Published: August 2011

Aim.  To explore nurses’ views and experiences regarding job satisfaction and their intention to leave in Shanghai.

Background.  The widespread nursing shortage and nurses’ high turnover rate has become a global issue. Job satisfaction is the most consistent predictor of nurses’ intention to leave and has been reported as explaining most of the variance on their intention to leave.

Design.  A cross‐sectional survey.

Methods.  A convenience sample of nurses was recruited from 19 large general hospitals in Shanghai and the research assistants distributed 2850 questionnaires to nurses. The response rate of this study was 78·95%, and 2250 nurses completed the questionnaire.

Results.  Regarding the overall job satisfaction, 50·2% nurses were dissatisfied and 40·4% nurses reported that they had intention to leave the current employment. Respondents’ characteristics had an impact on job satisfaction and their intention to leave. The results showed that age, marital status, work experience, overall job satisfaction, job satisfaction: extrinsic rewards, interaction, praise/recognition and control/responsibility were significant factors contributing to nurses’ intention to leave.

Conclusions.  The finding may be a cause of concern for hospital management and highlights the importance of the two concepts (job satisfaction and intention to leave) in Shanghai. Innovative and adaptable managerial interventions need to be taken to improve nurses’ job satisfaction and to strengthen their intention to stay.

Relevance to clinical practice.  Our findings outline some issues contributing to these problems and provide nurse administrators with information regarding specific influences on nurses’ job satisfaction and intention to leave in Shanghai and innovative and adaptable managerial interventions that are needed. Our findings may also provide direction for nurse managers and healthcare management to implement strategies to improve nurses’ job satisfaction and their intention to stay.
A pressure ulcer prevention programme specially designed for nursing homes: does it work?
Authors: Kwong Enid W‐Y , Lau Ada T‐Y , Lee Rainbow L‐P , Kwan Rick Y‐C
Published: August 2011

Aim.  The aim of this study was to evaluate a pressure ulcer prevention programme for nursing homes to ascertain the feasibility of its implementation, impact on care staff and outcomes for pressure ulcer knowledge and skills and pressure ulcer reduction.

Background.  No pressure ulcer prevention protocol for long‐term care settings has been established to date. The first author of this study thus developed a pressure ulcer prevention programme for nursing homes.

Design.  A quasi‐experimental pretest and post‐test design was adopted.

Methods.  Forty‐one non‐licensed care providers and eleven nurses from a government‐subsidised nursing home voluntarily participated in the study. Knowledge and skills of the non‐licensed care providers were assessed before, immediately after and six weeks after the training course, and pressure ulcer prevalence and incidence were recorded before and during the protocol implementation. At the end of the programme implementation, focus group interviews with the subjects were conducted to explore their views on the programme.

Results.  A statistically significant improvement in knowledge and skills scores amongst non‐licensed care providers was noted. Pressure ulcer prevalence and incidence rates dropped from 9–2·5% and 2·5–0·8%, respectively, after programme implementation. The focus group findings indicated that the programme enhanced the motivation of non‐licensed care providers to improve their performance of pressure ulcer prevention care and increased communication and cooperation amongst care staff, but use of the modified Braden scale was considered by nurses to increase their workload.

Conclusion.  A pressure ulcer prevention programme for nursing homes, which was feasible and acceptable, with positive impact and outcome in a nursing home was empirically developed.

Relevance to clinical practice.  The study findings can be employed to modify the programme and its outcomes for an evaluation of effectiveness of the programme through a randomised controlled trial.
Validation of an automated wireless system to monitor sleep in healthy adults
Authors: SHAMBROOM JOHN R. , FÁBREGAS STEPHAN E. , JOHNSTONE JACK
Published: August 2011

The availability of a reliable system to record sleep stage measures easily and automatically in ambulatory settings could be of utility for research and clinical work. The aim of this study was to evaluate a novel wireless system (WS) that does not require skilled preparation for the automatic collection and scoring of human sleep. Twenty‐nine healthy adults underwent concurrent sleep measurement via the WS, polysomnography (PSG) and an actigraph (ACT) in a sleep laboratory for one assessment night preceded by an acclimation night. The PSG recordings were scored by two experienced trained technicians from separate laboratories. Each recording was scored by both technicians to Rechtschaffen and Kales (R&K) criteria. The WS and ACT were compared with each of the PSG scores and a consensus PSG score, and the PSG scores were compared with each other. Inter‐rater agreement was assessed for each pair over all pooled epochs by percentage agreement, Cohen’s kappa and intraclass correlation coefficient. The WS agreement with each of the two PSG scores for sleep stages was 75.8 and 74.7%, respectively. WS agreement with each of the two PSG scores for sleep/wakefulness was 92.6 and 91.1%, ACT agreement with PSG was 86.3 and 85.7%. The PSG scorers’ agreement with each other for sleep stages was 83.2%, and for sleep/wakefulness was 95.8%. The findings from the current study indicate that the WS may provide an easy to use and accurate complement to other established technologies for measuring sleep in healthy adults.
Pharmacokinetics and pharmacodynamics of protamine zinc recombinant human insulin in healthy dogs
Authors: CLARK M. , THOMASETH K. , HEIT M. , HOENIG M.
Published: August 2011

Clark, M., Thomaseth, K., Heit, M., Hoenig, M. Pharmacokinetics and pharmacodynamics of protamine zinc recombinant human insulin in healthy dogs. J. vet. Pharmacol. Therap. 35, 342–350.

Protamine zinc insulins are generally considered to be long acting, with slow absorption from subcutaneous tissue. Protamine zinc recombinant human insulin (PZIR) may be useful to treat diabetic dogs. The purpose of this study was to describe the pharmacokinetics and pharmacodynamics of PZIR in dogs. PZIR was administered subcutaneously to 10 healthy Beagles using an incomplete crossover design, at doses of 0.3 or 0.5 U/kg (each n = 5), 0.8 U/kg (n = 10), or 0.8 U/kg at three separate sites (n = 6). Insulin and glucose concentrations were measured over 24 h. The shapes of insulin and glucose curves were variable among dogs, and the relationship between insulin dose, concentration, and glucose‐lowering effect was nonlinear. For single‐site 0.8 U/kg, median (range) onset of action was 3.5 h (0.5–10 h), time to glucose nadir was 14 h (5 to >24 h), and duration of action was >24 h (16 to >24 h). Mathematical model predictions of times to 50% and 90% insulin absorption, and fraction of insulin absorbed in 24 h, were not significantly different among protocols. Results confirm the tendency toward a late onset and long duration of action for PZIR in dogs. This insulin may be an alternative treatment option for diabetic dogs.
Effects of muscarinic receptor antagonists on acetylcholine‐induced contractions of jejunal smooth muscle in horses
Authors: TEIXEIRA‐NETO F. J. , McDONELL W. N. , BLACK W. D. , HARRIS W. , GROVUM L.
Published: August 2011

Teixeira‐Neto, F. J., McDonell, W. N., Black, W. D., Harris, W., Grovum, L. Effects of muscarinic receptor antagonists on acetylcholine‐induced contractions of jejunal smooth muscle in horses.J. vet. Pharmacol. Therap. 35, 313–318.

This study investigated the effects of a muscarinic type 1 (M1), 2 (M2), and 3 (M3) antagonists (4‐DAMP, pirenzepine, and methoctramine, respectively) on acetylcholine (Ach)‐induced contractions of longitudinal jejunal muscle strips of horses. Strips were irrigated with Krebs‐Henseleit solution gassed with 95% O2and 5% CO2, and the developed tension in response to Ach was recorded before and after incubation with increasing concentrations of 4‐DAMP (10−8–10−6 m), pirenzepine (10−6–10−4 m), and methoctramine (10−5–10−3 m). When competitive antagonism was characterized, the affinity constant (pA2) was calculated by Schild plots. A parallel rightward shift in the concentration–response curves was observed after 4‐DAMP and pirenzepine. Methoctramine presented a dual effect on the concentration–response curves: lower concentrations induced a parallel rightward shift without altering the maximum intensity of contraction (Emax), while the highest concentration increased slope of the concentration–response curve and increased Emax. The pA2for 4‐DAMP and pirenzepine was 9.18 and 7.13, respectively. Acetylcholine‐induced contractions of longitudinal jejunal smooth muscle are mediated mainly via M3receptors. The complex role of M2receptors in jejunal smooth muscle contractions was evident because methoctramine potentiated the contractile response to higher doses of Ach.
Costs of interventions for AIDS orphans and vulnerable children
Authors: Santa‐Ana‐Tellez Yared , DeMaria Lisa M. , Galárraga Omar
Published: August 2011

Objective  To review the published and grey literature for information regarding the costs and cost‐effectiveness of interventions aimed at improving the welfare of orphans and vulnerable children owing to HIV/AIDS in low‐ and middle‐income countries.

Method  We carried out a search of the peer‐reviewed literature through PubMed, EconLit, and Web of Science for the period January 2000 to December 2010. We also extensively reviewed the grey literature through generalized web searches and consultations with experts and searches of the web pages of the main organizations active in providing services to orphans and vulnerable children (OVC). The search yielded 216 articles; cross‐sectional or longitudinal studies and articles that did not address specific interventions were not considered. The remaining 21 articles were categorized by domain and by type of intervention strategy.

Results  All studies reviewed were carried out in sub‐Saharan Africa. All outcomes are expressed as cost per child per year (in 2010 USD). Foster care estimates range from $614 to $1921. Educational support for primary school ranged from $30 to $75. Health interventions that would ensure child survival can be delivered for about $55.

Conclusion  More research is needed to improve planning and delivery of interventions for OVC. The paucity of cost and cost‐effectiveness data reflects the limited number of effectiveness studies. Nevertheless, this systematic literature review shows evidence that suggests that in the area of housing, foster care appears to be more cost effective than institutional care (orphanages).
Access to, use of and satisfaction with health services among adults enrolled in Brazil’s Family Health Strategy: evidence from the 2008 National Household Survey
Authors: Macinko James , Lima Costa Maria F.
Published: August 2011

Objective To assess the effects of participation in Brazil’s primary healthcare programme (the Family Health Strategy or FHS) on access, use and satisfaction with health services among adults.

Methods Data are from the 2008 National Household Survey (PNAD) on 264 754 adults. This cross‐sectional analysis compares FHS enrollees to both non‐enrollees and those with private health plans. We calculated predicted probabilities of each outcome stratified by household wealth quintile, rural/urban location and sex using robust Poisson regression. We performed propensity score analysis to assess the differences in access among FHS enrollees and the rest of the population, once relevant socio‐demographic characteristics and other determinants of access were balanced.

Results Compared to families with neither FHS enrolment nor private health plans, adult FHS enrollees were generally more likely to have a usual source of care, to have visited a doctor or dentist in the past 12 months, to have access to needed medications and to be satisfied with the care they received. The FHS effect was largest among urban dwellers and the poorest.

Conclusions The FHS appears to be associated with enhanced access to and utilization of health services in Brazil. However, it has not yet been able to match levels of access experienced by those with private health plans, perhaps because the population served by the FHS is among the poorest, most rural and least healthy in the country.
Prevalence and risk factors of polyomavirus BK replication in simultaneous pancreas/kidney transplant recipients from a single transplant center
Authors: Mindlova Martina , Boucek Petr , Saudek Frantisek , Skibova Jelena , Jedinakova Teodora , Lipar Kvetoslav , Adamec Milos , Hirsch Hans H.
Published: August 2011

Mindlova M, Boucek P, Saudek F, Skibova J, Jedinakova T, Lipar K, Adamec M, Hirsch HH. Prevalence and risk factors of polyomavirus BK replication in simultaneous pancreas/kidney transplant recipients from a single transplant center.  Clin Transplant 2011 DOI: 10.1111/j.1399‐0012.2011.01488.x.  © 2011 John Wiley & Sons A/S.

Abstract:  Background:  BK virus (BKV) replication is considered as a marker of risk for polyomavirus BK‐associated nephropathy (PVAN). We evaluated the occurrence and risk factors for BKV DNA positivity following simultaneous pancreas/kidney transplantation (SPK).

Methods:  Point prevalence of BK viruria and viremia was assessed in 183 SPK recipients. Real‐time polymerase chain reaction was used with a detection threshold of 103 copies/mL. High‐level BKV positivity was defined as viruria and/or viremia >107 and >104 copies/mL, respectively. BKV‐positive patients were retested after 4–13 months and underwent an additional six‐month clinical follow‐up.

Results:  Urine and serum BKV positivity was detected in 28 (17.3% of available samples) and 7 (3.8%) patients, with high‐level viruria and viremia occurring in 6 (3.7%) and 3 (1.6%) patients, respectively. PVAN was biopsy‐confirmed in 1 and suspected as a cause of progressive renal failure in another SPK recipient. Patients with single low‐level viruria did not progress to high‐level positivity or PVAN at follow‐up. In multivariate analysis, pre‐transplant diabetes duration and delayed graft function were independently associated with BKV positivity.

Conclusions:  Point prevalence of high‐level BKV positivity and PVAN was low in SPK recipients from a single center. Diabetes duration and delayed graft function were independent risk factors for BKV replication.
Two novel HLA‐A alleles, A*29:02:01:02 and A*68:01:01:02, were identified by genomic full‐length cloning and sequencing
Authors: Xu Y. , Li Z. , Zou H. , Deng Z.
Published: August 2011

Two novel HLA‐A alleles differing from their closest related alleles by nucleotide exchanges in introns, A*29:02:01:02 and A*68:01:01:02, were identified.
Full‐length sequence of a novel HLA‐B*15:220 allele identified in an individual from Guadeloupe
Authors: Joannes M. O. R. F. , Voorter C. E. M. , Agis F. , Tilanus M. G. J.
Published: August 2011

The new HLA‐B*15:220 allele shows a single‐nucleotide substitution in exon 1 at position 47 (C>T) when compared to its closest allele HLA‐B*15:03:01, resulting in an amino acid substitution from Ala to Val in the signal peptide at codon −9.
Full‐length sequence of a novel null allele HLA‐A*23:38N identified in an individual from Guadeloupe
Authors: Joannes M. O. R. F. , Voorter C. E. M. , Agis F. , Tilanus M. G. J.
Published: August 2011

The new HLA‐A*23:38N allele shows a single‐base deletion in exon 2, resulting in a frame shift and a premature stop codon.
Assessing the accuracy of small satellite transmitters on free‐living flying‐foxes
Authors: McKEOWN ADAM , WESTCOTT DAVID A.
Published: August 2011

Satellite telemetry using ARGOS platform transmitter terminals (PTTs) is widely used to track the movements of animals, but little is known of the accuracy of these systems when used on active terrestrial mammals. An accurate estimate of the error, and therefore the limitations of the data, is critical when assessing the level of confidence in results. ARGOS provides published 68th percentile error estimates for the three most accurate location classes (LCs), but studies have shown that the errors can be far greater when the devices are attached to free‐living animals. Here we use data from a study looking at the habitat use of the spectacled flying‐fox in the wet tropics of Queensland to calculate these errors for all LCs in free‐living terrestrial mammals, and use these results to assess what level of confidence we would have in habitat use assignment in the study area. The results showed that our calculated 68th percentile errors were larger than the published ARGOS errors for all LCs, and that for all classes the error frequency had a very long tail. Habitat use results showed that the size of the error compared with the scale of the habitat the study was conducted in makes it unlikely that our data can be used to assess habitat use with great confidence. Overall, our results show that while satellite telemetry results are useful for assessing large scale movements of animals, in complex landscapes they may not be accurate enough to be used for finer scale analysis including habitat use assessment.
Response of plant species and life form diversity to variable fire histories and biomass in the jarrah forest of south‐west Australia
Authors: PEKIN BURAK K. , WITTKUHN ROY S. , BOER MATTHIAS M. , MACFARLANE CRAIG , GRIERSON PAULINE F.
Published: August 2011

Frequent fires reduce the abundance of woody plant species and favour herbaceous species. Plant species richness also tends to increase with decreasing vegetation biomass and cover due to reduced competition for light. We assessed the influence of variable fire histories and site biomass on the following diversity measures: woody and herbaceous species richness, overall species richness and evenness, and life form evenness (i.e. the relative abundance or dominance among six herbaceous and six woody plant life forms), across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands in south‐west Australia. Fire frequency was defined as the total number of fires over a 30‐year period. Overall species richness and species evenness did not vary with fire frequency or biomass. However, there were more herbaceous species (particularly rushes, geophytes and herbs) where there were fewer shrubs and low biomass, suggesting that more herbaceous species coexist where dominance by shrubs is low. Frequently burnt plots also had lower number and abundance of shrub species. Life form evenness was also higher at both high fire frequency and low biomass sites. These results suggest that the impact of fire frequency and biomass on vegetation composition is mediated by local interactions among different life forms rather than among individual species. Our results demonstrate that measuring the variation in the relative diversity of different woody and herbaceous life forms is crucial to understanding the compositional response of forests and other structurally complex vegetation communities to changes in disturbance regime such as increased fire frequency.
Corymbia leaf oils, latitude, hybrids and herbivory: A test using common‐garden field trials
Authors: NAHRUNG HELEN F. , HAYES R. ANDREW , WAUGH RACHEL , LAWSON SIMON A.
Published: August 2011

Foliar oils, particularly monoterpenes, can influence the susceptibility of plants to herbivory. In plants, including eucalypts, monoterpenes are often associated with plant defence. A recent analysis revealed an increase in foliar oil content with increasing latitudinal endemism, and we tested this pattern using three eucalypt taxa comprising a latitudinal replacement cline. We also examined the relative concentrations of two monoterpenes (α‐pinene and 1,8‐cineole), for which meta‐analyses also showed latitudinal variation, using hybrids of these three taxa with Corymbia torelliana. These, and pure C. torelliana, were then assessed in common‐garden field plots for the abundance and distribution of herbivory by four distinct herbivore taxa. Differing feeding strategies among these herbivores allowed us to test hypotheses regarding heritability of susceptibility and relationships to α‐pinene and 1,8‐cineole. We found no support for an increase in foliar oil content with increasing latitude, nor did our analysis support predictions for consistent variation in α‐pinene and 1,8‐cineole contents with latitude. However, herbivore species showed differential responses to different taxa and monoterpene contents. For example, eriophyid mites, the most monophagous of our censused herbivores, avoided the pure species, but fed on hybrid taxa, supporting hypotheses on hybrid susceptibility. The most polyphagous herbivore (leaf blister sawfly Phylacteophaga froggatti) showed no evidence of response to plant secondary metabolites, while the distribution and abundance patterns of Paropsis atomaria showed some relationship to monoterpene yields.
Co‐metabolic conversion of toluene in anaerobic n‐alkane‐degrading bacteria
Authors: Rabus Ralf , Jarling René , Lahme Sven , Kühner Simon , Heider Johann , Widdel Friedrich , Wilkes Heinz
Published: August 2011

Diverse microorganisms have been described to degrade petroleum hydrocarbons anaerobically. Strains able to utilize n‐alkanes do not grow with aromatic hydrocarbons, whereas strains able to utilize aromatic hydrocarbons do not grow with n‐alkanes. To investigate this specificity in more detail, three anaerobic n‐alkane degraders (two denitrifying, one sulfate‐reducing) and eight anaerobic alkylbenzene degraders (five denitrifying, three sulfate‐reducing) were incubated with mixtures of n‐alkanes and toluene. Whereas the toluene degradationers formed only the characteristic toluene‐derived benzylsuccinate and benzoate, but no n‐alkane‐derived metabolites, the n‐alkane degraders formed toluene‐derived benzylsuccinate, 4‐phenylbutanoate, phenylacetate and benzoate besides the regular n‐alkane‐derived (1‐methylalkyl)succinates and methyl‐branched alkanoates. The co‐metabolic conversion of toluene by anaerobic n‐alkane degraders to the level of benzoate obviously follows the anaerobic n‐alkane degradation pathway with C‐skeleton rearrangement and decarboxylation rather than the β‐oxidation pathway of anaerobic toluene metabolism. Hence, petroleum‐derived aromatic metabolites detectable in anoxic environments may not be exclusively formed by genuine alkylbenzene degraders. In addition, the hitherto largely unexplored fate of fumarate hydrogen during the activation reactions was examined with (2,3‐2H2)fumarate as co‐substrate. Deuterium was completely exchanged with hydrogen at the substituted carbon atom (C‐2) of the succinate adducts of n‐alkanes, whereas it is retained in toluene‐derived benzylsuccinate, regardless of the type of enzyme catalysing the fumarate addition reaction.
Role of remuneration committee in narrative human capital disclosure
Authors: Abeysekera Indra
Published: August 2011

This study empirically investigates whether independent directors on the remuneration committee influence narrative human capital disclosure (NAHCD) in firms where independent directors dominate the board composition. NAHCD is measured by frequency of occurrence, using latent content analysis in the annual reports of the top 30 listed firms on the Colombo Stock Exchange from 1998 to 2006. This study examines two attributes of corporate governance, controlling for other corporate governance attributes and firm‐level attributes. The findings highlight the importance of considering a firm’s independent director involvement in the remuneration committee when determining NAHCD strategy.
Antidepressant‐like effect of riparin II from Aniba riparia in mice: evidence for the involvement of the monoaminergic system
Authors: Teixeira Caroline Porto Leite , de Melo Carla Thiciane Vasconcelos , de Araújo Fernando Luiz Oliveira , de Carvalho Allyne Mara Rodrigues , Silva Maria Izabel Gomes , Barbosa‐Filho José Maria , Macêdo Danielle Silveira , de Barros Viana Glauce Socorro , de Sousa Francisca Cléa Florenço
Published: August 2011

In a previous study conducted by our group, riparin II (ripII) isolated from the green fruit of Aniba riparia presented antianxiety effects in mice. This study investigates a possible antidepressant activity of rip II using two predictive tests for antidepressant activity in rodents: the forced swimming test (FST) and tail suspension test (TST). Additionally, the mechanisms involved in the antidepressant‐like effect in mice were also assessed. Rip II was acute administered by intraperitoneal (i.p.) and oral (p.o) routes to male mice at doses of 25 and 50 mg/kg. Results showed that ripII at both tested doses and administration routes produced a significant decrease of immobility time in FST and TST. The pretreatment of mice with prazosin (1 mg/kg, i.p., an α1‐adrenoceptor antagonist), SCH23390 (15 μg/kg, i.p., a dopamine D1 receptor antagonist), sulpiride (50 mg/kg, i.p., a dopamine D2 receptor antagonist), p‐chlorophenylalanine (100 mg/kg, an inhibitor of serotonin synthesis), or NAN‐190 (0.5 mg/kg, a serotonin 5‐HT1A receptor antagonist) completely blocked the anti‐immobility effects elicited by riparin II (50 mg/kg, p.o.) in the FST. This study indicates that riparin II produces significant antidepressant‐like activity in the forced swimming and TSTs, and this effect seems to be dependent on its interaction with noradrenergic, dopaminergic, and serotonergic systems.
Hepatocyte growth factor stimulates root growth during the development of mouse molar teeth
Authors: Sakuraba H. , Fujiwara N. , Sasaki‐Oikawa A. , Sakano M. , Tabata Y. , Otsu K. , Ishizeki K. , Harada H.
Published: August 2011

Sakuraba H, Fujiwara N, Sasaki‐Oikawa A, Sakano M, Tabata Y, Otsu K, Ishizeki K, Harada H. Hepatocyte growth factor stimulates root growth during the development of mouse molar teeth. J Periodont Res 2012; 47: 81–88. © 2011 John Wiley & Sons A/S

Background and Objective:  It is well known that tooth root formation is initiated by the development of Hertwig’s epithelial root sheath (HERS). However, relatively little is known about the regulatory mechanisms involved in root development. As hepatocyte growth factor (HGF) is one of the mediators of epithelial–mesenchymal interactions in rodent tooth, the objective of this study was to examine the effects of HGF on the root development of mouse molars.

Material and Methods:  The HERS of mouse molars and HERS01a, a cell line originated from HERS, were used in this study. For detection of HGF receptors in vivo and in vitro, we used immunochemical procedures. Root development was assessed by implanting molar tooth germs along with HGF‐soaked beads into kidney capsules, by counting cell numbers in HERS01a cell cultures and by performing a 5′‐bromo‐2′‐deoxyuridine (BrdU) assay in an organ‐culture system.

Results:  HGF receptors were expressed in the enamel epithelium of molar germs as well as in HERS cells. HGF stimulated root development in the transplanted tooth germs, the proliferation of HERS01a cells in culture and HERS elongation in the organ‐culture system. Examination using BrdU revealed that cell proliferation in HERS was increased by treatment with HGF, especially that in the outer layer of HERS. This effect was down‐regulated when antibody against HGF receptor was present in the culture medium.

Conclusion:  Our results raise the possibility that HGF signaling controls root formation via the development of HERS. This study is the first to show that HGF is one of the stimulators of root development.
Effects of adhesive dressings on stratum corneum conductance
Authors: Cavallini Maurizio , Gazzola Riccardo , Vaienti Luca
Published: August 2011

Background

Stratum corneum is a fundamental layer of epidermis. It acts as a barrier, with antimicrobial features, regulating skin permeability and integrity as well. Adhesive dressings and their removal could alter this layer, affecting cutaneous water balance and lipid composition of stratum corneum. These changes could be monitored by measurement of cutaneous hydration.

Methods

Ninety‐two patients affected by wounds dressed with adhesive tapes or plasters have been studied. Measurement of skin conductance under tape/plaster and in the surrounding healthy skin, immediately after removal of dressing has been performed. Dressing age, wound localization, and characteristics were also considered.

Results

Adhesive dressings alter significantly stratum corneum conductance. Although healthy skin hydration has significant variations throughout the body, cutaneous conductance under adhesive dressing in different areas displays no significative changes. Moreover, the increase in hydration due to adhesive tapes/plasters showed no association with wound dehiscence.

Discussion

Adhesive dressings cause a significative increase in stratum corneum conductance, acting as a barrier to apocrine secretions. Although different hydration levels have been observed in healthy skin throughout the body, no difference exists under adhesive dressing among different regions, suggesting no contraindications in their employment throughout the body.

Conclusion

Increase in cutaneous hydration showed no correlations with wound dehiscence, thus confirming safety and practicality of these dressings.
Computer‐aided pattern classification system for dermoscopy images
Authors: Abbas Qaisar , Emre Celebi M. , Fondón Irene
Published: August 2011

Background

Computer‐aided pattern classification of melanoma and other pigmented skin lesions is one of the most important tasks for clinical diagnosis. To differentiate between benign and malignant lesions, the extraction of color, architectural order, symmetry of pattern and homogeneity (CASH) is a challenging task.

Methods

In this article, a novel pattern classification system (PCS) based on the clinical CASH rule is presented to classify among six classes of patterns. The PCS system consists of the following five steps: transformation to the CIE L*a*b* color space, pre‐processing to enhance the tumor region and removal of hairs, tumor‐area segmentation, color and texture feature extraction, and finally, classification based on a multiclass support vector machine.

Results

The PCS system is tested on a total of 180 dermoscopic images. To test the performance of the PCS diagnostic classifier, the area under the receiver operating characteristics curve (AUC) is utilized. The proposed classifier achieved a sensitivity of 91.64%, specificity of 94.14%, and AUC of 0.948.

Conclusion

The experimental results demonstrate that the proposed pattern classifier is highly accurate and classify between benign and malignant lesions into some extend. The PCS method is fully automatic and can accurately detect different patterns from dermoscopy images using color and texture properties. Additional pattern features can be included to investigate the impact of pattern classification based on the CASH rule.
Two‐dimensional dielectric imaging for dermatologic screening: a feasibility study
Authors: Habibi Mohammad , Olasz Edit B. , Klemer David P.
Published: August 2011

Background/purpose

The diagnosis of skin neoplasia can be very challenging, given the low sensitivity and specificity of traditional methods of diagnosis which are based on visual appearance. Techniques which are based on the dielectric properties of cells can improve the diagnostic accuracy of screening techniques; as an example, point‐contact coaxial probes for dielectric measurement can improve diagnostic accuracy. Unfortunately, these probes are not well suited for two‐dimensional spatial imaging of the skin surface, given that they must be manually scanned over the skin surface.

Methods/Results

An electronic scanning probe was developed and fabricated to simulate an open‐ended coaxial probe suitable for two‐dimensional dielectric imaging of human skin in real time. A clinical study was undertaken to demonstrate proof‐of‐concept for the instrumentation. A select group of normal healthy subjects as well as a subject with diagnosed squamous cell carcinoma participated in this study. The electronic scanning probe was found to be a potentially useful tool for providing two‐dimensional images from diseased skin.

Conclusion

The electronic scanning probe used for the present study addresses existing limitations with current coaxial probes. Measurements of healthy and diseased areas of skin are provided to illustrate the feasibility of the approach.
Comparative analysis of cytochrome P450‐like genes from Locusta migratoria manilensis: expression profiling and response to insecticide exposure
Authors: Guo Yan‐Qiong , Zhang Jian‐Zhen , Yang Mei‐Ling , Yan Liang‐Zhen , Zhu Kun Yan , Guo Ya‐Ping , Ma En‐Bo
Published: August 2011

Abstract  The cytochrome P450 monooxygenase (cytochrome P450) gene superfamily comprises many genes that may be involved in the biotransformations of pesticides and other xenobiotics. To date, very little is known about cytochrome P450 genes in the oriental migratory locust, Locusta migratoria manilensis. In this study, we carried out a genome‐wide analysis of cytochrome P450 genes of the locust to identify putative cytochrome P450 genes and characterize their expression responses to insecticide exposures. We identified 15 cytochrome P450‐like genes from a locust expressed sequence tag database (LocustDB). Reverse transcription polymerase chain reaction (RT‐PCR) analysis showed that most cytochrome P450‐like genes displayed different tissue and developmental stage expression patterns. However, most of them were predominantly expressed in the midgut, gastric caeca, fatbodies, and/or hindgut. Biochemical analysis showed that cytochrome P450 was differentially affected by three different insecticides. Deltamethrin caused significant inductions in 12 h at LD30 (dose to kill 30% of the tested individuals) in the nymphs, whereas malathion and carbaryl did not have significant effect on cytochrome P450 enzyme activity. Further RT‐PCR analysis showed significant increases of transcriptions of several cytochrome P450 genes in deltamethrin‐treated locusts. Thus, the increased cytochrome P450 enzyme activity is likely due to increased transcriptions of multiple cytochrome P450 genes in response to deltamethrin exposure. These results are expected to help us better understand the interactions between insecticides and major detoxification enzymes, and possible changes of the susceptibility to other insecticides in deltamethrin‐treated insects at various molecular levels.
Stochastic Reduced-Order Model in Low-Frequency Dynamics in Presence of Numerous Local Elastic Modes
Authors: Soize C. , Batou A.
Published: August 2011

This paper deals with the nonusual case in structural dynamics for which a complex structure exhibits both the usual global elastic modes and numerous local elastic modes in the low-frequency range. Despite the presence of these local elastic modes, we are interested in constructing a stochastic reduced-order model using only the global modes and in taking into account the local elastic modes with a probabilistic approach. In the first part, a formulation and an algorithm, which allow the “global elastic modes” and the “local elastic modes” to be calculated, are presented. The second part is devoted to the construction of the stochastic reduced-order model with the global elastic modes and in taking into account the uncertainties on the effects of the local elastic modes by the nonparametric probabilistic approach. Finally, an application, which validates the proposed theory is presented.
An Empirical Relationship for Extrapolating Sparse Experimental Lap Joint Data
Authors: Starr Michael J. , Segalman Daniel J.
Published: August 2011

Correctly incorporating the influence of mechanical joints in built-up mechanical systems is a critical element for model development for structural dynamics predictions. Quality experimental data are often difficult to obtain and is rarely sufficient to determine fully parameters for relevant mathematical models. On the other hand, fine-mesh finite element (FMFE) modeling facilitates innumerable numerical experiments at modest cost. Detailed FMFE analysis of built-up structures with frictional interfaces reproduces trends among problem parameters found experimentally, but there are qualitative differences. Those differences are currently ascribed to the very approximate nature of the friction model available in most finite element codes. Though numerical simulations are insufficient to produce qualitatively correct behavior of joints, some relations, developed here through observations of a multitude of numerical experiments, suggest interesting relationships among joint properties measured under different loading conditions. These relationships can be generalized into forms consistent with data from physical experiments. One such relationship, developed here, expresses the rate of energy dissipation per cycle within the joint under various combinations of extensional and clamping load in terms of dissipation under other load conditions. The use of this relationship—though not exact—is demonstrated for the purpose of extrapolating a representative set of experimental data to span the range of variability observed from real data.
Extended Kantorovich Method for Three-Dimensional Elasticity Solution of Laminated Composite Structures in Cylindrical Bending
Authors: Kapuria Santosh , Kumari Poonam
Published: August 2011

The extended Kantorovich method originally proposed by Kerr in the year 1968 for two-dimensional (2D) elasticity problems is further extended to the three-dimensional (3D) elasticity problem of a transversely loaded laminated angle-ply flat panel in cylindrical bending. The significant extensions made to the method in this study are (1) the application to the 3D elasticity problem involving an in-plane direction and a thickness direction instead of both in-plane directions in 2D elasticity problems, (2) the treatment of the nonhomogeneous boundary conditions encountered in the thickness direction, and (3) the use of a mixed variational principle to obtain the governing differential equations in both directions in terms of displacements as well as stresses. This approach not only ensures exact satisfaction of all boundary conditions and continuity conditions at the layer interfaces, but also guarantees the same order of accuracy for all displacement and stress components. The method eventually leads to a set of eight algebraic-ordinary differential equations in the in-plane direction and a similar set of equations in the thickness direction for each layer of the laminate. Exact closed form solutions are obtained for each system of equations. It is demonstrated that the iterative procedure converges very fast irrespective of whether or not the initial guess functions satisfy the boundary conditions. Comparisons of the present predictions with the available 3D exact solutions and 3D finite element solutions for laminated cross-ply and angle-ply composite panels under different boundary conditions show a close agreement between them.
Global Optimization of Plug-In Hybrid Vehicle Design and Allocation to Minimize Life Cycle Greenhouse Gas Emissions
Authors: Norman Shiau Ching-Shin , Michalek Jeremy J.
Published: August 2011

We pose a reformulated model for optimal design and allocation of conventional (CV), hybrid electric (HEV), and plug-in hybrid electric (PHEV) vehicles to obtain global solutions that minimize life cycle greenhouse gas (GHG) emissions of the fleet. The reformulation is a twice-differentiable, factorable, nonconvex mixed-integer nonlinear programming (MINLP) model that can be solved globally using a convexification-based branch-and-reduce algorithm. We compare results to a randomized multistart local-search approach for the original formulation and find that local-search algorithms locate global solutions in 59% of trials for the two-segment case and 18% of trials for the three-segment case. The results indicate that minimum GHG emissions are achieved with a mix of PHEVs sized for 25–45 miles of electric travel. Larger battery packs allow longer travel on electrical energy, but production and weight of underutilized batteries result in higher GHG emissions. Under the current average U.S. grid mix, PHEVs offer a nearly 50% reduction in life cycle GHG emissions relative to equivalent conventional vehicles and about 5% improvement over HEVs when driven on the standard urban driving cycle. Optimal allocation of different PHEVs to different drivers turns out to be of second order importance for minimizing net life cycle GHGs.
Incorporating Moldability Considerations During the Design of Polymer Heat Exchangers
Authors: Cevallos Juan , K. Gupta S. , Bar-Cohen Avram
Published: August 2011

Recently, available formulations of thermally enhanced polymer composites are attractive in heat exchanger applications due to their low cost and improved corrosion resistance compared to the conventional metal options. This paper presents a systematic approach to the design of plate-fin heat exchangers made out of thermally enhanced polymer composites. We have formulated the design problem as the life cycle cost minimization problem. The integrated design model introduced here accounts for heat transfer performance, molding cost, and assembly costs. We have adopted well-known models to develop individual parametric models that describe how heat transfer performance, molding cost, and assembly cost varies as a function of the geometric parameters of the heat exchanger. Thermally enhanced polymer composites behave differently from the conventional polymers during the molding process. The desired thin walled large structures are expected to pose challenges during the filling phase of the molding process. Hence, we have utilized experimentally validated simulations to develop a metamodel to identify difficult and impossible to mold design configurations. This metamodel has been integrated within the overall formulation to address the manufacturability considerations. This paper also presents several case studies that show how the material and labor cost strongly influence the final design.
Mechanisms for sealing of porous low-k SiOCH by combined He and NH3 plasma treatment
Authors: Shoeb Juline , Kushner Mark J.
Published: August 2011

Porous dielectric materials, such as SiOCH, are used as the insulator in interconnect wiring in microelectronics devices to lower the dielectric constant and so decrease the RC time delay. Sealing of the pores (up to a few nm in diameter) is necessary to prevent degradation of the low-k properties during subsequent processing steps by diffusion of reactants through the pores into the material. Sequential treatment of porous SiOCH by He and NH3 plasmas is potentially a means of sealing pores while maintaining the low-k of the dielectric. The He plasma activates surface sites to accelerate the reactions responsible for pore sealing. NH3 plasma treatment completes the sealing through one of two mechanisms resulting from the adsorption of NHx radicals — catalyzing the formation of a densified surface layer or formation of Si-N, C-N and N-N bonds to bridge over the pore. In this paper, we discuss mechanisms for pore sealing bridging bonds based on results from an integrated computational investigation of the etching, cleaning, activation and sealing of porous SiOCH in sequential Ar/C4F8/O2, Ar/O2, He and Ar/NH3 plasmas. The authors found that pores in excess of 1 nm in radius are difficult to seal due to the inability of N-bonding to bridge the pore opening. Factors affecting the sealing efficiency, such as treatment time, average pore radius and aspect ratio are discussed.
Reference dosimetry during diagnostic CT examination using XR‐QA radiochromic film model
Authors: Boivin Jonathan , Tomic Nada , Fadlallah Bassam , DeBlois François , Devic Slobodan
Published: August 2011

Purpose:

The authors applied 2D reference dosimetry protocol for dose measurements using XR‐QA radiochromic film model during diagnostic computed tomography (CT) examinations carried out on patients and humanoid Rando phantom.

Methods:

Response of XR‐QA model GAFCHROMIC™ film reference dosimetry system was calibrated in terms of Air‐Kerma in air. Four most commonly used CT protocols were selected on their CT scanner (GE Lightspeed VCT 64), covering three anatomical sites (head, chest, and abdomen). For each protocol, 25 patients ongoing planned diagnostic CT examination were recruited. Surface dose was measured using four or eight film strips taped on patients' skin and on Rando phantom. Film pieces were scanned prior to and after irradiation using Epson Expression™ 10000XL document scanner. Optical reflectance of the unexposed film piece was subtracted from exposed one to obtain finalnet reflectance change, which is subsequently converted to dose using previously established calibration curves.

Results:

The authors' measurements show that body skin dose variation has a sinusoidal pattern along the scanning axis due to the helical movement of the x‐ray tube, and a comb pattern for head dose measurements due to its axial movement. Results show that the mean skin dose at anterior position for patients is (51 ± 6) mGy, (29 ± 11) mGy, (45 ± 13) mGy and (38 ± 20) mGy for head, abdomen, angio Abdomen, and chest and abdomen protocol (UP position), respectively. The obtained experimental dose length products (DLP) show higher values than CT based DLP taken from the scanner console for body protocols, but lower values for the head protocol. Internal dose measurements inside the phantom's head indicate nonuniformity of dose distribution within scanned volume.

Conclusions:

In this work, the authors applied an Air‐Kerma in air based radiochromic film reference dosimetry protocol forin vivo skin dose measurements. In this work, they employed green channel extracted from the scanned RGB image for dose measurements in the range from 0 to 200 mGy. Measured skin doses and corresponding DLPs were higher than DLPs provided by the CT scanner manufacturer as they were measured on patients' skin.
Improved image quality for x‐ray CT imaging of gel dosimeters
Authors: Kakakhel M. B. , Kairn T. , Kenny J. , Trapp J. V.
Published: August 2011

Purpose:

This study provides a simple method for improving precision of x‐ray computed tomography (CT) scans of irradiated polymer gel dosimetry. The noise affecting CT scans of irradiated gels has been an impediment to the use of clinical CT scanners for gel dosimetry studies.

Methods:

In this study, it is shown that multiple scans of a single PAGAT gel dosimeter can be used to extrapolate a “zero‐scan” image which displays a similar level of precision to an image obtained by averaging multiple CT images, without the compromised dose measurement resulting from the exposure of the gel to radiation from the CT scanner.

Results:

When extrapolating the zero‐scan image, it is shown that exponential and simple linear fits to the relationship between Hounsfield unit and scan number, for each pixel in the image, provide an accurate indication of gel density.

Conclusions:

It is expected that this work will be utilized in the analysis of three‐dimensional gel volumes irradiated using complex radiotherapy treatments.