bluuebunny/crossref_metadata_2025 huggingface dataset:
Seroprevalence and risk factors of toxoplasmosis in cattle from extensive and semi-intensive rearing systems at Zona da Mata, Minas Gerais state, Southern Brazil
Authors: Fajardo Hugo Vieira , D’ávila Sthefane , Bastos Ronaldo Rocha , Cyrino Carolina Dutra , de Lima Detoni Michelle , Garcia João Luis , das Neves Leandro Batista , Nicolau José Leonardo , Amendoeira Maria Regina Reis
Published: June 2013

Background

Concerning the infection of humans byT. gondii,limited efforts have been directed to the elucidation of the role of horizontal transmission between hosts. One of the main routes of transmission from animals to humans occurs through the ingestion of raw or insufficiently cooked meat. However, even though the detection ofT. gondiiin meat constitutes an important short-term measure, control strategies can only be accomplished by a deeper understanding of the epidemiology of toxoplasmosis. The present study aimed to investigate the seroprevalence of toxoplasmosis in cattle from Zona da Mata, Minas Gerais, Brazil, and to identify associated risk factors, through an epidemiological investigation.

Methods

The animals studied (Bos indicus,breed Nelore or Gir) were reared in the Zona da Mata micro-region and killed at a commercial slaughterhouse at Juiz de Fora, Minas Gerais state. The animals came from 53 cattle farms with extensive (predominantly pasture feeding management) or semi-intensive (food management based on grazing, salt mineral and feed supplementation) rearing systems. Blood samples were collected from 1200 animals, and assigned toIndirect Fluorescent Antibody Test.

Results

When analyzing IgG anti-T.gondiiwe found an overall seroprevalence of 2.68%. In Brazil prevalences vary from 1.03% to 60%. Although in the present study, the seroprevalence per animal is considered low compared to those observed in other studies, we found out that of the 53 farms analyzed, 17 (34.69%) had one or more positive cattle. It is a considerable percentage, suggesting that the infection is well distributed through the Zona da Mata region. The results of the epidemiological investigation showed that the main risk factors ofToxoplasma gondiiinfection are related to animal management and to the definive host. There was a relationship between the number of seropositive cattle and the presence and number of resident cats, presence and number of stray cats, presence of cats walking freely, rat control by using cats and feed storage.

Conclusion

These results may contribute to the development of preventive strategies in Brazil and other developing countries were extensive and semi-intensive cattle rearing systems are very widespread and the efforts to control this important zoonotic disease have attained little success.
Early microvascular dysfunction in cerebral small vessel disease is not detectable on 3.0 Tesla magnetic resonance imaging: a longitudinal study in spontaneously hypertensive stroke-prone rats
Authors: Mencl Stine , Garz Cornelia , Niklass Solveig , Braun Holger , Göb Eva , Homola György , Heinze Hans-Jochen , Reymann Klaus G , Kleinschnitz Christoph , Schreiber Stefanie
Published: June 2013

Background

Human cerebral small vessel disease (CSVD) has distinct histopathologic and imaging findings in its advanced stages. In spontaneously hypertensive stroke-prone rats (SHRSP), a well-established animal model of CSVD, we recently demonstrated that cerebral microangiopathy is initiated by early microvascular dysfunction leading to the breakdown of the blood–brain barrier and an activated coagulatory state resulting in capillary and arteriolar erythrocyte accumulations (stases). In the present study, we investigated whether initial microvascular dysfunction and other stages of the pathologic CSVD cascade can be detected by serial magnetic resonance imaging (MRI).

Findings

Fourteen SHRSP and three control (Wistar) rats (aged 26–44 weeks) were investigated biweekly by 3.0 Tesla (3 T) MRI. After perfusion, brains were stained with hematoxylin–eosin and histology was correlated with MRI data. Three SHRSP developed terminal CSVD stages including cortical, hippocampal, and striatal infarcts and macrohemorrhages, which could be detected consistently by MRI. Corresponding histology showed small vessel thromboses and increased numbers of small perivascular bleeds in the infarcted areas. However, 3 T MRI failed to visualize intravascular erythrocyte accumulations, even in those brain regions with the highest densities of affected vessels and the largest vessels affected by stases, as well as failing to detect small perivascular bleeds.

Conclusion

Serial MRI at a field strength of 3 T failed to detect the initial microvascular dysfunction and subsequent small perivascular bleeds in SHRSP; only terminal stages of cerebral microangiopathy were reliably detected. Further investigations at higher magnetic field strengths (7 T) using blood- and flow-sensitive sequences are currently underway.
Missing women in the United Kingdom
Authors: Adamou Adamos , Drakos Christina , Iyer Sriya
Published: June 2013

This paper investigates the gender-selection decisions of immigrants in the United Kingdom, using data from the 1971–2006 General Household Survey. We examine sex-selection in the UK among immigrant families and the gender composition of previous births, conditional on socio-economic characteristics. Our key result is that better-educated immigrants balance their family after the birth of two sons, by having a daughter thereafter. Our study also is the first to estimate the number of missing women among Asian immigrants in a European country, contributing to research on the US and Canada that missing women are also a phenomenon of the developed world.

JEL codes

J13, J15, O52, Z13
Thermal stress effects on grain yield in Brachypodium distachyon occur via H2A.Z-nucleosomes
Authors: Boden Scott A , Kavanová Monika , Finnegan E Jean , Wigge Philip A
Published: June 2013

Background

Crop plants are highly sensitive to ambient temperature, with a 1 ºC difference in temperature sufficient to affect development and yield. Monocot crop plants are particularly vulnerable to higher temperatures during the reproductive and grain-filling phases. The molecular mechanisms by which temperature influences grain development are, however, unknown. In Arabidopsis thaliana, H2A.Z-nucleosomes coordinate transcriptional responses to higher temperature. We therefore investigated whether the effects of high temperature on grain development are mediated by H2A.Z-nucleosomes.

Results

We have analyzed the thermal responses of the Pooid grass, Brachypodium distachyon, a model system for crops. We find that H2A.Z-nucleosome occupancy is more responsive to increases in ambient temperature in the reproductive tissue of developing grains compared withvegetative seedlings. This difference correlates with strong phenotypic responses of developing grain to increased temperature, including early maturity and reduced yield. Conversely, temperature has limited impact on the timing of transition from the vegetative to generative stage, with increased temperature unable to substitute for long photoperiod induction of flowering. RNAi silencing of components necessary for H2A.Z-nucleosome deposition is sufficient to phenocopythe effects of warmer temperature on grain development.

Conclusions

H2A.Z-nucleosomes are important in coordinating the sensitivity of temperate grasses to increased temperature during grain development. Perturbing H2A.Z occupancy, through higher temperature or genetically, strongly reduces yield. Thus, we provide a molecular understanding of the pathways through which high temperature impacts on yield. These findings may be useful for breeding crops resilient to thermal stress.
Mapping gene activity of Arabidopsis root hairs
Authors: Lan Ping , Li Wenfeng , Lin Wen-Dar , Santi Simonetta , Schmidt Wolfgang
Published: June 2013

Background

Quantitative information on gene activity at single cell-type resolution is essential for the understanding of how cells work and interact. Root hairs, or trichoblasts, tubular-shaped outgrowths of specialized cells in the epidermis, represent an ideal model for cell fate acquisition and differentiation in plants.

Results

Here, we provide an atlas of gene and protein expression in Arabidopsis root hair cells, generated by paired-end RNA sequencing and LC/MS-MS analysis of protoplasts from plants containing a pEXP7-GFP reporter construct. In total, transcripts of 23,034 genes were detected in root hairs. High-resolution proteome analysis led to the reliable identification of 2,447 proteins, 129 of which were differentially expressed between root hairs and non-root hair tissue. Dissection of pre-mRNA splicing patterns showed that all types of alternative splicing were cell type-dependent, and less complex in EXP7-expressing cells when compared to non-root hair cells. Intron retention was repressed in several transcripts functionally related to root hair morphogenesis, indicative of a cell type-specific control of gene expression by alternative splicing of pre-mRNA. Concordance between mRNA and protein expression was generally high, but in many cases mRNA expression was not predictive for protein abundance.

Conclusions

The integrated analysis shows that gene activity in root hairs is dictated by orchestrated, multilayered regulatory mechanisms that allow for a cell type-specific composition of functional components.
Revised International Prognostic Scoring System (IPSS) Predicts Survival and Leukemic Evolution of Myelodysplastic Syndromes Significantly Better Than IPSS and WHO Prognostic Scoring System: Validation by the Gruppo Romano Mielodisplasie Italian Regional Database
Authors: Voso Maria Teresa , Fenu Susanna , Latagliata Roberto , Buccisano Francesco , Piciocchi Alfonso , Aloe-Spiriti Maria Antonietta , Breccia Massimo , Criscuolo Marianna , Andriani Alessandro , Mancini Stefano , Niscola Pasquale , Naso Virginia , Nobile Carolina , Piccioni Anna Lina , D'Andrea Mariella , D'Addosio Ada , Leone Giuseppe , Venditti Adriano
Published: June 2013

Purpose

The definition of disease-specific prognostic scores plays a fundamental role in the treatment decision-making process in myelodysplastic syndrome (MDS), a group of myeloid disorders characterized by a heterogeneous clinical behavior.

Patients and Methods

We applied the recently published Revised International Prognostic Scoring System (IPSS-R) to 380 patients with MDS, registered in an Italian regional database, recruiting patients from the city of Rome (Gruppo Romano Mielodisplasie). Patients were selected based on the availability of IPSS-R prognostic factors, including complete peripheral-blood and bone marrow counts, informative cytogenetics, and follow-up data.

Results

We validated the IPSS-R score as a significant predictor of overall survival (OS) and leukemia-free survival (LFS) in MDS (P < .001 for both). When comparing the prognostic value of the International Prognostic Scoring System (IPSS), WHO Prognostic Scoring System (WPSS), and IPSS-R, using the Cox regression model and the likelihood ratio test, a significantly higher predictive power for LFS and OS became evident for the IPSS-R, compared with the IPSS and WPSS (P < .001 for both). The multivariate analysis, including IPSS, WPSS, age, lactate dehydrogenase, ferritin concentration, Eastern Cooperative Oncology Group performance status, transfusion dependency, and type of therapy, confirmed the significant prognostic value of IPSS-R subgroups for LFS and OS. Treatment with lenalidomide and erythropoiesis-stimulating agents was shown to be an independent predictor of survival in the multivariate analysis.

Conclusion

Our data confirm that the IPSS-R is an excellent prognostic tool in MDS in the era of disease-modifying treatments. The early recognition of patients at high risk of progression to aggressive disease may optimize treatment timing in MDS.
Styles, Stereotypes, and the South: Constructing Identities at the Linguistic Border
Authors: Cramer Jennifer
Published: June 2013

Where two dialect areas collide, one finds border regions, which serve as dynamic sites for identity construction. Louisville, Kentucky, in its position on the south side of the Ohio River, the geographical and political border between Kentucky and Indiana, is located at one such collision. While previous work in Louisville has demonstrated the border nature of the city, both in terms of linguistic production and perception, this article examines how individual speakers use different styles in their production of regional identity at the border. Specifically, this study addresses how speakers in Louisville define the area to which Louisville belongs. Using the theoretical notions of enregisterment, iconization, and recursivity, the author shows how these individuals, in recognition of the border, dynamically construct identities that are at the same time Southern and non-Southern, which provides further evidence of the fluid and hybrid nature of identities at the border.
Distinct binding interactions of HIV-1 Gag to Psi and non-Psi RNAs: Implications for viral genomic RNA packaging
Authors: Webb Joseph A. , Jones Christopher P. , Parent Leslie J. , Rouzina Ioulia , Musier-Forsyth Karin
Published: June 2013

Despite the vast excess of cellular RNAs, precisely two copies of viral genomic RNA (gRNA) are selectively packaged into new human immunodeficiency type 1 (HIV-1) particles via specific interactions between the HIV-1 Gag and the gRNA psi (ψ) packaging signal. Gag consists of the matrix (MA), capsid, nucleocapsid (NC), and p6 domains. Binding of the Gag NC domain to ψ is necessary for gRNA packaging, but the mechanism by which Gag selectively interacts with ψ is unclear. Here, we investigate the binding of NC and Gag variants to an RNA derived from ψ (Psi RNA), as well as to a non-ψ region (TARPolyA). Binding was measured as a function of salt to obtain the effective charge (Zeff) and nonelectrostatic (i.e., specific) component of binding,Kd(1M). Gag binds to Psi RNA with a dramatically reducedKd(1M)and lowerZeffrelative to TARPolyA. NC, GagΔMA, and a dimerization mutant of Gag bind TARPolyA with reducedZeffrelative to WT Gag. Mutations involving the NC zinc finger motifs of Gag or changes to the G-rich NC-binding regions of Psi RNA significantly reduce the nonelectrostatic component of binding, leading to an increase inZeff. These results show that Gag interacts with gRNA using different binding modes; both the NC and MA domains are bound to RNA in the case of TARPolyA, whereas binding to Psi RNA involves only the NC domain. Taken together, these results suggest a novel mechanism for selective gRNA encapsidation.
Endovenous Laser Application
Authors: Pongratz T. , Siegrist K. , Burgmeier C. , Barth H.-D. , Schmedt C.-G. , Sroka R.
Published: June 2013

Introduction: Endoluminal vein treatment is a promising minimal invasive treatment option for peoples suffering from varicose veins. The basic mechanism underlying this procedure is to selectively induce heat in the vessel wall with the result of denaturation of proteins and shrinkage of collagen fibers due to energy application. So far energy could be applied either as RF-current, laser light or water steam. The different approaches to deliver such forms of energies are described.

Methods: Investigations on heat dependent vein tissue effects were performed. The degree of shrinkage and wall thickening due to heat induction was calculated. Tensile test on vein tissue were performed. Investigation using the radial emitting laser fibre in the ox-foot-model under reproducible condition were done and wavelengths dependent tissue reaction were explored.

Results: The experiments clearly demonstrate the degree of the shrinkage of length and diameter, the thickening of the vein wall, as well as the decrease of the elasticity of the tissue. The optical irradiation pattern of the radial emitting laser fiber serves for safe and reproducible energy application directly to the vein wall. Using a laser wavelength with high absorption by the tissue water needs reduced irradiation and irradiance compared to wavelengths with less water absorption. Conclusion: An experimental approach to improve laser application for endovenous varicose treatment is described. Laser parameters and treatment parameters were found which are now under clinical testing. The demonstrated tissue effects may help to find further arguments for clinical findings and sensations described by the patients during follow-up.
Modelling the Heat and Mass Transfer during Hot Pressing of Medium Density Fibreboard
Authors: Gupta Arun , Jordan Patrick , Pang Shusheng
Published: June 2013

This paper discusses the development of a one-dimensional mathematical model to describe the heat and mass transfer during the hot-compression of medium density fibreboard (MDF) composite panels. Five primary variables were considered during the model development: air content, water vapour content, bound water content, and temperature within the mat, and the extent of the cure of the adhesive system, characterized by the cure index. Different heat and mass transfer processes were identified for the transport of the heat and the moisture phases. The heat was transported by conduction and convection due to a temperature gradient, and the exothermic energy released by the curing of the urea formaldehyde resin, while the water phases were transported by bulk flow and diffusion due to total pressure and concentration gradients. The resulting differential-algebraic equation system was solved by the finite difference method. The mathematical model predicted temperature, moisture content, partial vapour pressures, and extent of adhesive cure within the mat structure under a typical hot-compression process. The model results allow a better understanding of the interacting mechanisms involved in a complex production process. The model can also assist to optimize the hot-pressing parameters for improved quality of MDF panel products, while reducing pressing time.
Selberg zeta functions on odd-dimensional hyperbolic manifolds of finite volume
Authors: Pfaff Jonathan
Published: June 2013

We study Selberg zeta functions Z(s,σ)
associated
to locally homogeneous vector bundles over the unit-sphere bundle
of a complete oriented odd-dimensional hyperbolic spin manifold of finite
volume. We assume a
certain condition on the fundamental group of the manifold. A priori, the Selberg zeta functions are defined only for s in some
right half-plane of ℂ. We will prove that for any locally homogeneous bundle
the functions Z(s,σ)
have a meromorphic continuation to ℂ and we will give a complete
description of their singularities in terms of spectral data of
the underlying manifold. Our work generalizes results of
Bunke and Olbrich to the non-compact situation. As an application of our results
one can compare the normalized Reidemeister torsions on hyperbolic 3-manifolds with
cusps which were introduced by Menal-Ferrer
and Porti to the corresponding regularized analytic torsions.
Determination of partially hydrolyzed polyacrylamide in wastewater produced from polymer flooding by colloid titration
Authors: Fang Shenwen , Duan Ming , Xia Yini , Wang Hu , Li Linyu
Published: June 2013

Colloid titration has been widely used to determine the charge carried by macromolecules and the concentration of anionic and cationic polyelectrolytes in paper making and food service industries. This method is simple and the materials used are non-volatile and harmless, but it has not previously been used to determine the partially hydrolyzed polyacrylamide (HPAM) in wastewater produced from polymer flooding. In this paper, colloid titration was used to determine the HPAM in wastewater produced from polymer flooding in an oilfield. When the HPAM concentration (Cp) was <200 mg/l, the relationship between the Cp and the titration value (Vp) was linear. This linear relationship was influenced by the pH of wastewater and the hydrolysis degree of HPAM; Vp increased with the pH and the hydrolysis degree. However, it was independent of the concentration of solubilized crude oil and salt concentration in the wastewater and the molecular weight of the HPAM. Recovery tests showed that the determination of HPAM in the wastewater by colloid titration was reliable. It was also found that the colloid titration and starch iodide method had similar accuracies for determination of the HPAM and that colloid titration was a better method for the analyst.
Improving On-Time Start of Day and End of Day for a Pediatric Surgical Service
Authors: Varughese Anna M. , Adler Elena , Anneken Amy , Kurth C. Dean
Published: June 2013

BACKGROUND AND OBJECTIVE:

In multicase pediatric ear, nose, and throat operating rooms (ORs), brief delays in early case start times often produce a cascading effect of lengthy delays by the end of the day and can often lead to patient, family, and staff dissatisfaction and increased labor costs due to unplanned overtime. We sought to improve actual end of day relative to scheduled end of day from 40% to 60%.

METHODS:

Key drivers of the process included case scheduling, ordering of sedative medications, and nurse availability in the postanesthesia care unit to receive the patient from the anesthesia provider. A multidisciplinary team conducted a series of tests of change addressing the various key drivers. Data were collected by using an independent, impartial data collector as well as being extracted from the hospital information technology system. Data were analyzed by using control charts and statistical process control methods.

RESULTS:

The percentage of ORs ending on time increased from 40% to 60%. Appropriate scheduling of complex cases increased from 10% to 87%, and accurate scheduling of case duration improved from 21% to 48%. Timely premedication increased from 55% to 90% and immediate availability of a nurse in the postanesthesia care unit from 68% to >90%.

CONCLUSIONS:

By applying quality-improvement methods, significant improvements were made in a multicase pediatric ear, nose, and throat OR. The impact can be significant by reducing wait times for patients, as well as staff overtime for the institution.
CT Scan Utilization Patterns in Pediatric Patients With Recurrent Headache
Authors: DeVries Andrea , Young Paul C. , Wall Eric , Getchius Thomas ScD , Li Chia-hsuan , Whitney John , Rosenberg Alan
Published: June 2013

OBJECTIVE:

Although unnecessary for children with headache and normal history, computed tomography (CT) scans are widely used. This study sought to determine current practice patterns of neuroimaging to diagnose pediatric headache in a variety of treatment settings and to identify factors associated with increased use of neuroimaging.

METHODS:

This retrospective claims analysis included children (aged 3–17 years) with ≥2 medical claims for headache. The primary outcome was CT scan utilization on or after first presentation with headache in a physician’s office or emergency department (ED).

RESULTS:

Of 15 836 patients, 26% (4034 patients; mean age: 11.8 years) had ≥1 CT scan, 74% within 1 month of index diagnosis. Patients with ED visits were 4 times more likely to undergo a CT scan versus those without ED visits (P < .001 [95% confidence interval: 3.9–4.8]). However, even outside the ED, use of CT scans remained widespread. Two-thirds of patients with CT scans had no ED use. Among patients with no ED utilization, >20% received a CT scan during the study period. Evaluation by a neurologist was strongly associated with a lower likelihood of CT scan compared with other provider specialties (odds ratio: 0.37; P < .01 [95% confidence interval: 0.30–0.46]).

CONCLUSIONS:

Use of CT scans to diagnose pediatric headache remains high despite existing guidelines, low diagnostic yield, and high potential risk. Implementing quality improvement initiatives to ensure that CT scans in children are performed only when truly indicated will reduce unnecessary exposure to ionizing radiation and associated cancer risks.
Cardiorespiratory Fitness and Adiposity in Metabolically Healthy Overweight and Obese Youth
Authors: Sénéchal Martin , Wicklow Brandy , Wittmeier Kristy , Hay Jacqueline , MacIntosh Andrea C. , Eskicioglu Pinar , Venugopal Niranjan , McGavock Jonathan M.
Published: June 2013

OBJECTIVE:

Controversy exists surrounding the contribution of fitness and adiposity as determinants of the Metabolically Healthy Overweight (MHO) phenotype in youth. This study investigated the independent contribution of cardiorespiratory fitness and adiposity to the MHO phenotype among overweight and obese youth.

METHODS:

This cross-sectional study included 108 overweight and obese youth classified as MHO (no cardiometabolic risk factors) or non-MHO (≥1 cardiometabolic risk factor), based on age- and gender-specific cut-points for fasting glucose, triglycerides, high-density lipoprotein cholesterol, systolic and diastolic blood pressure, and hepatic steatosis.

RESULTS:

Twenty-five percent of overweight and obese youth were classified as MHO. This phenotype was associated with lower BMI z-score (BMI z-score: 1.8 ± 0.3 vs 2.1 ± 0.4, P = .02) and waist circumference (99.7 ± 13.2 vs 106.1 ± 13.7 cm, P = .04) compared with non-MHO youth. When matched for fitness level and stratified by BMI z-score (1.6 ± 0.3 vs 2.4 ± 0.2), the prevalence of MHO was fourfold higher in the low BMI z-score group (27% vs 7%; P = .03). Multiple logistic regression analyses revealed that the best predictor of MHO was the absence of hepatic steatosis even after adjusting for waist circumference (odds ratio 0.57, 95% confidence interval 0.40–0.80) or BMI z-score (odds ratio 0.59, 95% confidence interval 0.43–0.80).

CONCLUSIONS:

The MHO phenotype was present in 25% of overweight and obese youth and is strongly associated with lower levels of adiposity, and the absence of hepatic steatosis, but not with cardiorespiratory fitness.
Office-Based Care for Lesbian, Gay, Bisexual, Transgender, and Questioning Youth
Authors: Levine David A. ,   the COMMITTEE ON ADOLESCENCE, Braverman Paula K. , Adelman William P. , Breuner Cora C. , Levine David A. , Marcell Arik V. , Murray Pamela J. , O’Brien Rebecca F.
Published: June 2013

This Technical Report was reaffirmed April 2021.

The American Academy of Pediatrics issued its last statement on homosexuality and adolescents in 2004.This technical report reflects the rapidly expanding medical and psychosocial literature about sexual minority youth. Pediatricians should be aware that some youth in their care may have concerns or questions about their sexual orientation or that of siblings, friends, parents, relatives, or others and should provide factual, current, nonjudgmental information in a confidential manner. Although most lesbian, gay, bisexual, transgender, and questioning (LGBTQ) youth are quite resilient and emerge from adolescence as healthy adults, the effects of homophobia and heterosexism can contribute to increased mental health issues for sexual minority youth. LGBTQ and MSM/WSW (men having sex with men and women having sex with women) adolescents, in comparison with heterosexual adolescents, have higher rates of depression and suicidal ideation, higher rates of substance abuse, and more risky sexual behaviors. Obtaining a comprehensive, confidential, developmentally appropriate adolescent psychosocial history allows for the discovery of strengths and assets as well as risks. Pediatricians should have offices that are teen-friendly and welcoming to sexual minority youth. This includes having supportive, engaging office staff members who ensure that there are no barriers to care. For transgender youth, pediatricians should provide the opportunity to acknowledge and affirm their feelings of gender dysphoria and desires to transition to the opposite gender. Referral of transgender youth to a qualified mental health professional is critical to assist with the dysphoria, to educate them, and to assess their readiness for transition. With appropriate assistance and care, sexual minority youth should live healthy, productive lives while transitioning through adolescence and young adulthood.
Unipolar Resistive Switching and Associated Photoresponse in Sm doped BiFeO3 Thin Film Grown by RF Sputtering
Authors: Katiyar Rajesh K. , Misra Pankaj , Sharma G. L , Morell Gerardo , Scott J. F , Katiyar Ram S.
Published: June 2013

Nonvolatile unipolar resistive switching has been observed in Sm doped BFO thin films in Pt/Sm: BFO/SRO stack geometry. The initial forming voltage was found to be ∼ 11 V. After the forming process repeatable switching of the resistance of Sm:BFO film was obtained between low and high resistance states with nearly constant resistance ratio ∼ 105 and non overlapping switching voltages in the range of 0.7-1 V and 4-6 V respectively. The temperature dependent measurements of the resistance of the device indicated metallic and semiconducting conduction behavior in low and high resistance states respectively. The current conduction mechanism of the Pt/Sm:BFO/SRO device in low resistance states was found to be dominated by the Ohmic behavior while in case of high resistance state and at high voltages it deviated significantly from normal Ohmic behavior and was found to correspond the Pool-Frankel (PF) emission. The Pt/Sm:BFO/SRO structure also showed efficient photo-response in high and low resistance states with increase in photocurrent which was significantly higher in low resistance state when illuminated with white light.
Novel intermediate reflector layer for optical and morphological tuning in the Micromorph thin film tandem cell
Authors: Orhan J.-B. , Vallat-Sauvain E. , Marmello M. , Kroll U. , Meier J. , Laux E. , Grange D. , Farine Brunner S. , Keppner H.
Published: June 2013

PECVD growth of the microcrystalline silicon junction on a highly textured amorphous top cell often leads to defective absorber layers and finally to low quality bottom cell. This paper reports on the current status of using an innovative smoothening/reflective layer (SRL) as alternative intermediate reflector between top and bottom cell of a Micromorph tandem device deposited on as-grown highly textured LPCVD ZnO layer. Manufacturing of the SRL layer is realized by “liquid phase” deposition technologies. Optical and electrical properties, smoothening effect and photoelectrical results of Micromorph tandem devices are discussed. The implementation of our novel SRL results in the growth of a crack-free bottom cell and to an efficient current transfer from the bottom to the top cell.
Temperature Dependence of 1/f Noise and Electrical Conductivity Measurements on p-type a-Si:H Devices
Authors: Lopes V. C. , Hanson E. , Whitfield D. , Shrestha K. , Littler C. L. , Syllaios A. J.
Published: June 2013

Noise and electrical conductivity measurements were made at temperatures ranging from approximately 270°K to 320°K on devices fabricated on as grown Boron doped p-type a-Si:H films. The room temperature 1/f noise was found to be proportional to the bias voltage and inversely proportional to the square root of the device area. As a result, the 1/f noise can be described by Hooge’s empirical expression [1]. The 1/f noise was found to be independent of temperature in the range investigated even though the device conductivity changed by a factor of approximately 4 over this range. Conductivity temperature measurements exhibit a T-0.25 dependence, indicative of conduction via localized states in the valence band tail [2,3]. In addition, multiple authors have analyzed hole mobility in a-Si:H and find that the hole mobility depends on the scattering of mobile holes by localized states in the valence band tail [4-7]. We conclude that the a-Si:H carrier concentration does not change appreciably with temperature, and thus, the resistance change in this temperature range is due to the temperature dependence of the hole mobility. Our results are applicable to a basic understanding of noise and conductivity requirements for a-Si:H materials used for microbolometer ambient temperature infrared detection.
Crystallization Kinetics of Plasma-Produced Amorphous Silicon Nanoparticles
Authors: Lopez Thomas , Mangolini Lorenzo
Published: June 2013

The use of a continuous flow non-thermal plasma reactor for the formation of silicon nanoparticles has attracted great interest because of the advantageous properties of the process [1]. Despite the short residence time in the plasma (around 10 milliseconds), a significant fraction of the precursor, silane, is converted and collected in the form of nanopowder. The structure of the produced powder can be tuned between amorphous and crystalline by adjusting the power of the radio-frequency excitation source, with higher power leading to the formation of crystalline particles. Numerical modeling suggests that higher excitation power results in a higher plasma density, which in turn increases the nanoparticle heating rate due to the interaction between ions, free radicals and the nanopowder suspended in the plasma [2]. While the experimental evidence suggests that plasma heating may be responsible for the formation of crystalline powder, an understanding of the mechanism that leads to the crystallization of the powder while in the plasma is lacking. In this work, we present an experimental investigation on the crystallization kinetic of plasma-produced amorphous powder. Silicon nanoparticles are nucleated and grown using a non-thermal plasma reactor similar to the one described in [1], but operated at low power to give amorphous nanoparticles in a 3-10 nm size range. The particles are then extracted from the reactor using an orifice and aerodynamically dragged into a low pressure reactor placed in a tube furnace capable of reaching temperatures up to 1000°C. Raman and TEM have been used to monitor the crystalline fraction of the material as a function of the residence time and temperature. It is expected that for a residence time in the annealing region of approximately ∼300 milliseconds, a temperature of at least 750 °C is needed to observe the onset of crystallization. A range of crystalline percentages can be observed from 750 °C to 830 °C. A discussion of particle growth and particle interaction, based on experimental evidence, will be presented with its relation to the overall effect on crystallization. Further data analysis allows extrapolating the crystallization rate for the case of this simple, purely thermal system. We conclude that thermal effects alone are not sufficient to explain the formation of crystalline powder in non-thermal plasma reactors.
Development of road infrastructure in Indonesia
Authors: Younger John Scott
Published: June 2013

The road network in Indonesia, as elsewhere, is vital in supporting current and future economic growth. Following a quick review of the early days, the development and issues over the past four decades are summarised, showing the emphasis paid at different times. The 1997/1998 Asian economic crisis acted as a significant brake on development, the effects of which were not felt immediately. Later manifestation has raised many problems related to skill development, shortage of quality route length and proper accountability. The adoption of democracy post 1998 with regionalisation in 1999, although laudable from a political and inclusive viewpoint, has led to related operational issues that need to be addressed. Indonesia has a satisfactory gross domestic product of greater than 6%, consumer driven and expected to continue in the years ahead. However, lack of infrastructure, with roads being particularly highlighted, clearly indicates that economic performance could benefit significantly from immediate strong investment.
Sensitivity-guided evaluation of the HBV hydrological model parameterization
Authors: Zelelew M. B. , Alfredsen K.
Published: June 2013

Applying hydrological models for river basin management depends on the availability of the relevant data information to constrain the model residuals. The estimation of reliable parameter values for parameterized models is not guaranteed. Identification of influential model parameters controlling the model response variations either by main or interaction effects is therefore critical for minimizing model parametric dimensions and limiting prediction uncertainty. In this study, the Sobol variance-based sensitivity analysis method was applied to quantify the importance of the HBV conceptual hydrological model parameterization. The analysis was also supplemented by the generalized sensitivity analysis method to assess relative model parameter sensitivities in cases of negative Sobol sensitivity index computations. The study was applied to simulate runoff responses at twelve catchments varying in size. The result showed that varying up to a minimum of four to six influential model parameters for high flow conditions, and up to a minimum of six influential model parameters for low flow conditions can sufficiently capture the catchments' responses characteristics. To the contrary, varying more than nine out of 15 model parameters will not make substantial model performance changes on any of the case studies.
Particle method of characteristics (PMOC) for unsteady pipe flow
Authors: Hwang Yao-Hsin , Huang Ho-Shuenn , Chung Nien-Mien , Wang Pai-Yi
Published: June 2013

A novel particle method of characteristics (PMOC) to simulate unsteady pipe flows is introduced and validated in the present study. Contrary to the conventional method of characteristics (MOC), the present formulation is built by reallocating the computational nodes along the characteristic lines. Both the right- and left-running characteristics are accurately traced and imitated with their associated computational particles. The annoying numerical inconveniences in the fixed-grid arrangement due to incompatible Courant–Friedrichs–Lewy (CFL) condition by repeating solution interpolations is effectively eliminated. Special particles with dual states satisfying the Rankine–Hugoniot relations are deliberately imposed to emulate the shock structure. Efficacy of this formulation is verified by solving some benchmark problems with significant transient effects in pipe flows. Computational results of piezometric head and flow velocity are meticulously compared with available analytical solutions. It is concluded that the proposed PMOC will be a useful tool to replicate transient phenomena in pipe flows.
Integrating evolution strategies and genetic algorithms with agent-based modeling for flushing a contaminated water distribution system
Authors: Zechman Emily M.
Published: June 2013

Water utilities can prepare for water distribution hazards, such as the presence of contaminants in the pipe network and failure of physical components. In contamination events, the complex interactions among managers' operational decisions, consumers' water consumption choices, and the hydraulics and contaminant transport in the water distribution system may influence the contaminant plume so that a typical engineering model may not properly predict public health consequences. A complex adaptive system (CAS) approach couples engineering models of a water distribution system with agent-based models of consumers and public officials. Development of threat management strategies, which prescribe a set of actions to mitigate public health consequences, is enabled through a simulation–optimization framework that couples evolutionary algorithms with the CAS model. Evolution strategies and genetic algorithm-based approaches are developed and compared for an illustrative case study to identify a flushing strategy for opening hydrants to minimize the number of exposed consumers and maintain acceptable levels of service in the network.
Short-term forecasting of urban storm water runoff in real-time using extrapolated radar rainfall data
Authors: Thorndahl S. , Rasmussen M. R.
Published: June 2013

Model-based short-term forecasting of urban storm water runoff can be applied in real-time control of drainage systems in order to optimize system capacity during rain and minimize combined sewer overflows, improve wastewater treatment or activate alarms if local flooding is impending. A novel online system, which forecasts flows and water levels in real-time with inputs from extrapolated radar rainfall data, has been developed. The fully distributed urban drainage model includes auto-calibration using online in-sewer measurements which is seen to improve forecast skills significantly. The radar rainfall extrapolation (nowcast) limits the lead time of the system to 2 hours. In this paper, the model set-up is tested on a small urban catchment for a period of 1.5 years. The 50 largest events are presented.
Understanding Cooperation in a Single-trial Prisoner's Dilemma Game: Interactions Among Three Conditions
Authors: Xi Yang , Li Tingyan , Zheng Yong
Published: June 2013

In the present study we investigated the mechanism inherent in the decision-making process in a single-trial with the game called Prisoner's Dilemma (PD), in which players might simultaneously encounter different conditions that influence cooperation: namely, reciprocity, perceived
control, and risk taking. We conducted 2 experiments to examine how, and to what extent, these conditions contribute to cooperation. By incorporating direct measurements of the potential conditions into a paradigm produced in previous studies, we were able to test the reliability of backward
inference and to quantify the effect exerted by each condition. Results consistently revealed a complex cognitive process in single-trial PD: each condition had an influence on decision making, but none of them showed a dominating power to prompt cooperation independently; reciprocity served
as a moderator.
Is Younger Really Better? Anxiety About Learning a Foreign Language in Turkish Children
Authors: Gürsoy Esim , Akin Feride
Published: June 2013

As one of the outcomes of globalization, learning a foreign language has gained importance. In many countries this situation has led to the lowering of the age for starting to learn a foreign language as part of the restructuring of the education system. Success in foreign language
learning (FLL) depends on many factors. Affective factors are 1 facet of achieving success in FLL and these factors have long been a concern of language educators. However, most research on this topic has been conducted with adolescents and adults. Thus, in the present case study our aim was
to investigate the relationship between age and FLL anxiety with children aged between 10 to 14 years. We used both qualitative and quantitative research methods for triangulation. We collected data via a questionnaire (Cronbach's alpha .876), adapted from Horwitz, Horwitz, and Cope (1986)
and via interviews with 84 children at a state primary school in Turkey. In addition to calculating means and standard deviations, we used Kruskal-Wallis and Mann-Whitney U tests for dual and multiple comparisons. The results suggested that there were no statistically significant differences
according to gender and that the younger children in the study were less anxious than the older children about FLL. Examinations were found to be the activity that caused the most anxiety for the children.
Psychological Contract Breach and Turnover Intention: The Moderating Roles of Adversity Quotient and Gender
Authors: Chin Pao-Ling , Hung Min-Li
Published: June 2013

We examined the relationship between psychological contract breach (PCB) and insurance industry workers' turnover intention. We also explored the moderating effects of adversity quotient (AQ) and gender on that relationship. The results showed that turnover intentions were positively
affected by PCB, and AQ significantly moderated that relationship. In contrast, the moderating effect of gender was not found to be significant. To retain employees, the findings of this study should be taken into account when developing training programs. However, future researchers should
concentrate on different aspects of AQ that may also be relevant to staff turnover.
AMPK: A Target for Drugs and Natural Products With Effects on Both Diabetes and Cancer
Authors: Hardie D. Grahame
Published: June 2013

The AMP-activated protein kinase (AMPK) is a highly conserved sensor of cellular energy that appears to have arisen at an early stage during eukaryotic evolution. In 2001 it was shown to be activated by metformin, currently the major drug for treatment for type 2 diabetes. Although the known metabolic effects of AMPK activation are consistent with the idea that it mediates some of the therapeutic benefits of metformin, as discussed below it now appears unlikely that AMPK is the sole target of the drug. AMPK is also activated by several natural plant products derived from traditional medicines, and the mechanisms by which they activate AMPK are discussed. One of these is salicylate, probably the oldest medicinal agent known to humankind. The salicylate prodrug salsalate has been shown to improve metabolic parameters in subjects with insulin resistance and prediabetes, and whether this might be mediated in part by AMPK is discussed. Interestingly, there is evidence that both metformin and aspirin provide some protection against development of cancer in humans, and whether AMPK might be involved in these effects is also discussed.
Feasibility of Outpatient Fully Integrated Closed-Loop Control
Authors: Kovatchev Boris P. , Renard Eric , Cobelli Claudio , Zisser Howard C. , Keith-Hynes Patrick , Anderson Stacey M. , Brown Sue A. , Chernavvsky Daniel R. , Breton Marc D. , Farret Anne , Pelletier Marie-Josée , Place Jérôme , Bruttomesso Daniela , Del Favero Simone , Visentin Roberto , Filippi Alessio , Scotton Rachele , Avogaro Angelo , Doyle Francis J.
Published: June 2013

OBJECTIVE

To evaluate the feasibility of a wearable artificial pancreas system, the Diabetes Assistant (DiAs), which uses a smart phone as a closed-loop control platform.

RESEARCH DESIGN AND METHODS

Twenty patients with type 1 diabetes were enrolled at the Universities of Padova, Montpellier, and Virginia and at Sansum Diabetes Research Institute. Each trial continued for 42 h. The United States studies were conducted entirely in outpatient setting (e.g., hotel or guest house); studies in Italy and France were hybrid hospital–hotel admissions. A continuous glucose monitoring/pump system (Dexcom Seven Plus/Omnipod) was placed on the subject and was connected to DiAs. The patient operated the system via the DiAs user interface in open-loop mode (first 14 h of study), switching to closed-loop for the remaining 28 h. Study personnel monitored remotely via 3G or WiFi connection to DiAs and were available on site for assistance.

RESULTS

The total duration of proper system communication functioning was 807.5 h (274 h in open-loop and 533.5 h in closed-loop), which represented 97.7% of the total possible time from admission to discharge. This exceeded the predetermined primary end point of 80% system functionality.

CONCLUSIONS

This study demonstrated that a contemporary smart phone is capable of running outpatient closed-loop control and introduced a prototype system (DiAs) for further investigation. Following this proof of concept, future steps should include equipping insulin pumps and sensors with wireless capabilities, as well as studies focusing on control efficacy and patient-oriented clinical outcomes.