bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immigration, Growth, and Unemployment: Panel VAR Evidence from OECD Countries
Authors: Boubtane Ekrame , Coulibaly Dramane , Rault Christophe 
Published: October 2013

AbstractThis paper examines empirically the interaction between immigration and host country economic conditions. We employ panel vector autoregression (VAR) techniques for a large annual data set on 22 OECD countries over the period 1987–2009. The VAR approach addresses the endogeneity problem by allowing for endogenous interactions between the variables in the system. Our results provide evidence of migration contribution to host economic prosperity (positive impact on GDP per capita and negative impact on aggregate unemployment, native‐ and foreign‐born unemployment rates). We also find that migration is influenced by host economic conditions (migration responds positively to host GDP per capita and negatively to host total unemployment rate).
Chloral hydrate sedation for magnetic resonance imaging in newborn infants
Authors: Finnemore Anna , Toulmin Hilary , Merchant Naz , Arichi Tom , Tusor Nora , Cox David , Ederies Ash , Nongena Phumza , Ko Christopher , Dias Ryan , Edwards Anthony D. , Groves Alan M. 
Published: October 2013

SummaryBackgroundThe aim of this study was to look for clinically significant adverse effects of chloral hydrate used in a large cohort of infants sedated for magnetic resonance imaging.MethodCase notes of infants who underwent magnetic resonance imaging (MRI) scanning from 2008 to 2010 were reviewed, with patient demographics, sedation dose, comorbidities, time to discharge, and side effects of sedation noted.ResultsFour hundred and eleven infants (median [range] postmenstrual age per weight at scan 42 [31+4–60] weeks per 3500 g [1060–9900 g]) were sedated with chloral hydrate (median [range] dose 50 [20–80] mg·kg−1). In three cases (0.7%), desaturations occurred which prompted termination of the scan. One infant (0.2%) was admitted for additional observation following sedation but had no prolonged effects. In 17 (3.1%) cases, infants had desaturations which were self‐limiting or responded to additional inspired oxygen such that scanning was allowed to continue.ConclusionWhen adhering to strict protocols, MRI scanning in newborn infants in this cohort was performed using chloral hydrate sedation with a relatively low risk of significant adverse effects.
Wnt inhibitory factor (WIF)‐1 promotes melanogenesis in normal human melanocytes
Authors: Park Tae Jun , Kim Misun , Kim Hyeran , Park Sun Yi , Park Kyoung‐Chan , Ortonne Jean‐Paul , Kang Hee Young 
Published: October 2013

SummaryWnt signaling plays a role in the differentiation as well as the development of melanocytes. Using a microarray analysis, hyperpigmentary skin of melasma expressed high levels of Wnt inhibitory factor‐1 (WIF‐1) compared with perilesional normal skin. In this study, the expression and functional roles of WIF‐1 on melanocytes were investigated. WIF‐1 was expressed both in the melanocytes of normal human skin and in cultured melanocytes. The upregulation of WIF‐1 on cultured normal human melanocytes significantly induced expressions of MITF and tyrosinase, which were associated with increased melanin content and tyrosinase activity. Consistent with the stimulatory effect of WIF‐1, WIF‐1 siRNA reduced melanogenesis in the cells. Moreover, WIF‐1 increases pigmentation in melanocytes co‐cultured with WIF‐1‐overexpressed fibroblasts and of organ‐cultured human skin. These findings suggest that melanocytes express WIF‐1 constitutively in vivo and in vitro and that WIF‐1 promotes melanogenesis in normal human melanocytes.
Synthesis, Characterization, Photophysics and Photochemistry of Pyrylogen Electron Transfer Sensitizers
Authors: Clennan Edward L. , Liao Chen 
Published: October 2013

AbstractA series of new dicationic sensitizers that are hybrids of pyrylium salts and viologens has been synthesized. The electrochemical and photophysical properties of these “pyrylogen” sensitizers are reported in sufficient detail to allow rationale design of new photoinduced electron transfer reactions. The range of their reduction potentials (+0.37–+0.05 V vs SCE) coupled with their range of singlet (48–63 kcal mol−1) and triplet (48–57 kcal mol−1) energies demonstrate that they are potent oxidizing agents in both their singlet and triplet excited states, thermodynamically capable of oxidizing substrates with oxidation potentials as high as 3.1 eV. The pyrylogens are synthesized in three steps from readily available starting materials in modest overall 11.4–22.3% yields. These sensitizers have the added advantages that: (1) their radical cations do not react on the CV timescale with oxygen bypassing the need to run reactions under nitrogen or argon and (2) have long wavelength absorptions between 413 and 523 nm well out of the range where competitive absorbance by most substrates would cause a problem. These new sensitizers do react with water requiring special precautions to operate in a dry reaction environment.
Genetic diversity of Botrytis in New Zealand vineyards and the significance of its seasonal and regional variation
Authors: Johnston P. R. , Hoksbergen K. , Park D. , Beever R. E. 
Published: October 2013

Species‐ and population‐specific differences in fungicide resistance and aggressiveness within Botrytis makes basic data on genetic diversity important for understanding disease caused by this fungus. Genetic diversity of Botrytis was surveyed between 2008 and 2012 from grapes from five New Zealand wine‐growing regions. A total of 1226 isolates were gathered from symptomless flower buds at the start of the growing season and 1331 isolates from diseased fruit at harvest. Two species were found, B. cinerea and B. pseudocinerea. Botrytis pseudocinerea was common in both Auckland vineyards sampled, and infrequent elsewhere. However, even in Auckland, it was rarely isolated from diseased fruit. The presence of the Boty and Flipper transposons was assessed. Isolates with all four transposon states (Boty only, Flipper only, both Boty and Flipper, no transposons) were found for both species. Both vineyards in the Auckland region had high numbers of Flipper‐only isolates at flowering; both vineyards from the Waipara region had high numbers of Boty‐only isolates at flowering. Most isolates from diseased fruit at harvest contained both transposons. These observations suggest that B. pseudocinerea, and isolates with one or both of the transposons missing, may be less aggressive than B. cinerea, or than isolates with both transposons present. Two clades were resolved within B. pseudocinerea, only one of which has been reported from European vineyards. Phylogenetic diversity within B. cinerea in New Zealand was similar to that known from Europe, including isolates that appear to match Botrytis ‘Group S’. The taxonomic implications of this genetic diversity are discussed.
Immunogenicity and Protective Efficacy Conferred by a Novel Recombinant Mycobacterium bovis Bacillus Calmette‐Guérin Strain Expressing Interleukin‐12p70 of Human Cytokine and Ag85A of Mycobacterium tuberculosis Fusion Protein
Authors: Deng Y. H. , He H. Y. , Zhang F. J. 
Published: October 2013

AbstractMycobacterium bovis bacillus Calmette‐Guérin (BCG) immunization provides protection against tuberculosis (TB) in infants, but the antituberculosis protective immunity wanes gradually after initial immunization and lasts less than 15 years. Therefore, more efficacious vaccines are urgently needed. In this study, we constructed a new tuberculosis vaccine of recombinant BCG strain (rBCG‐IA), which could express IL‐12p70 of human cytokine and Ag85A of M. tuberculosis fusion protein, and investigated its immunogenicity in BALB/c mice by measuring antibody titres, proliferation rate of splenocytes, ratios of CD4+ T and CD8+ T cells stimulated by specific antigens and levels of IFN‐γ production in antigen‐stimulated splenocyte cultures. Meanwhile, we evaluated its protective efficacy against M. tuberculosis H37Rv infection through detecting lung histopathology, organ bacterial loads and lung acid‐fast stain. Immunogenicity experiments illustrated that from 2nd to 8th week after immunization, the rBCG‐IA vaccine was able to induce the highest level of antibody titres, proliferation rate of splenocytes and IFN‐γ production among groups and gained improved ratio of CD4+ T and CD8+ T cells from 6th to 8th week after vaccination. And from 2nd to 8th week after M. tuberculosis H37Rv infection, the score of pathology and bacterial loads in the rBCG‐IA group were obviously lower than that in rBCG‐I group, rBCG‐A group or control group (PBST group), but similar to that in BCG group. This study suggested that rBCG‐IA was able to elicit stronger humoral and cellular immune responses, but could only confer similar protective efficacy compared with its parental BCG vaccine.
Male‐sterile maize plants produced by targeted mutagenesis of the cytochrome P450‐like gene (MS26) using a re‐designed I–CreI homing endonuclease
Authors: Djukanovic Vesna , Smith Jeff , Lowe Keith , Yang Meizhu , Gao Huirong , Jones Spencer , Nicholson Michael G. , West Ande , Lape Janel , Bidney Dennis , Carl Falco Saverio , Jantz Derek , Alexander Lyznik Leszek 
Published: October 2013

SummaryThe I–CreI homing endonuclease from Chlamydomonas reinhardti has been used as a molecular tool for creating DNA double‐strand breaks and enhancing DNA recombination reactions in maize cells. The DNA‐binding properties of this protein were re‐designed to recognize a 22 bp target sequence in the 5th exon of MS26, a maize fertility gene. Three versions of a single‐chain endonuclease, called Ems26, Ems26+ and Ems26++, cleaved their intended DNA site within the context of a reporter assay in a mammalian cell line. When the Ems26++ version was delivered to maize Black Mexican Sweet cells by Agrobacterium‐mediated transformation, the cleavage resulted in mutations at a co‐delivered extra‐chromosomal ms26‐site in up to 8.9% of the recovered clones. Delivery of the same version of Ems26 to immature embryos resulted in mutations at the predicted genomic ms26‐site in 5.8% of transgenic T0 plants. This targeted mutagenesis procedure yielded small deletions and insertions at the Ems26 target site consistent with products of double‐strand break repair generated by non‐homologous end joining. One of 21 mutagenized T0 plants carried two mutated alleles of the MS26 gene. As expected, the bi‐allelic mutant T0 plant and the T1 progeny homozygous for the ms26 mutant alleles were male‐sterile. This paper described the second maize chromosomal locus (liguless‐1 being the first one) mutagenized by a re‐designed I–CreI–based endonuclease, demonstrating the general utility of these molecules for targeted mutagenesis in plants.
Numerical Analysis of Flow in S-Duct Diffusers With and Without Flow Control
Authors: Sullerey R. K. , Bhat S. P. 
Published: October 2013

The intakes of Unmanned Ariel Vehicles (UAV) and Unmanned Combat Ariel Vehicles (UCAV) have complex serpentine geometries that include curvature, area increase and offsets. This is from the requirements of stealth features in such inlets. There is also a design requirement to keep the intake length short. Tight geometrical curvatures coupled with flow diffusion are known to generate secondary flows and many a time lead to flow separation. So flow at the exit may be quite distorted and total pressure losses may be high. Therefore some kind of flow control is required to ensure that the design goals of pressure recovery and flow quality are maintained.
Significant previous research has been carried out by one of the authors on flow control in S-Duct and serpentine duct geometries with various options of passive and active controls (1, 2, 3 and 4). In one of the latest of such studies (5), very encouraging results have been obtained in improving performance of S-duct diffusers using a zero net mass flow (ZNMF) active control. The present paper is a CFD study on modeling the flow in such a duct with and without flow control. As large amount of experimental data is available for both passive and active control on this geometry, it can be used to validate CFD predictions. The experimental results are available for improvement in pressure recovery and reduction of flow distortion using both passive and active flow controls including a combination of suction and blowing (vortex generator jets) for low-subsonic flow regime. Once the CFD model is proven to make good predictions for the present geometry, the same could be applied to more complex and realistic intake geometries.
The numerical (CFD) study carried out is a turbulent flow analysis in S-duct geometry to estimate pressure recovery and flow distortion with and without use of flow control techniques. The flow is modeled inside a rectangular section S-shaped duct with a Reynolds number of 1.479×105 based on the intake duct height. The diffusing duct has an area ratio of 1.25. The location of vortex generators and suction are based on the benchmarked experimental data (5) and is remodeled for CFD computations. The analysis is carried out for the low-subsonic (incompressible) flow and the CFD results are compared with the experimental results. The results obtained for bare duct and zero net mass flow (ZNMF) agree very well with the experimental data. As such, in future, work can be carried out at high subsonic, more complicated geometries and at various vortex generator jet angles to optimize the pressure recovery for high Mach number flows.
Numerical Investigation of High Pressure Hydrogen Released in Air
Authors: Umesh U. , De Ashoke , Das Malay K. 
Published: October 2013

The constantly growing energy needs of the world accompanied by the emphasis on environmental pollution control have driven us to look at the possibility of hydrogen as a potential source of energy for the future. However, there are serious self-ignition hazards associated with its use, which are not yet fully understood phenomena. The issue of spontaneous ignition of highly pressurized hydrogen release is an important safety concern and it is necessary to understand its mechanism in order to adopt adequate safety measures.
This paper describes a numerical investigation of the flow physics of a high-pressure hydrogen gas released through a tube into the atmosphere. The formation of a strong shock wave ahead of the high-pressure hydrogen jet causes an increase in temperature of the ambient atmospheric air, thereby leading to the possibility of ignition of the hydrogen-air mixture formed at the contact surface. The analysis of the physical mechanism of shock propagation and associated temperature profiles of the flow field are presented. Parametric studies based on the numerical results of temperature profiles obtained for the various initial conditions of release pressure and tube length have been carried out to study their effects on this high-pressure hydrogen gas behaviour and how they would favour occurrence of spontaneous ignition.
Investigations Into Creep Behavior of Gas Turbine Component Assemblies
Authors: Raghavan Kotur S. 
Published: October 2013

Modern day gas turbines are very complex in construction and consist of a very large number of smaller parts and subassemblies. Hence the most vital parts of the entire assembly are the mechanical devices which are deployed to connect and keep them together. In gas turbines two approaches are normally used in the assembly process. They are the threaded fasteners such as bolt and nut and shrunk-fit or interference-fit assemblies. In the high temperature regions of the gas turbines the effect of creep on the integrity of such fastening arrangements needs to be assessed at the design stage.
A problem commonly faced pertains to lack of creep data which would facilitate detailed nonlinear analysis. The available data invariably exhibit scatter. In this paper parametric studies are undertaken. Creep curves are chosen so that both primary and secondary stages are accounted for. The coefficients are chosen to meet the design needs.
The performance of bolted joints and shrunk-fit assemblies get affected over time due to stress relaxation leading to loss of bolt pretension or the effective interference. The bolt preload as well as the interference is to be optimally chosen. Higher the preload or the interference the more effective is the joint. At the same time the stress levels are higher and hence the stresses will relax to a greater extent. For a design stage assessment of the behavior of assemblies there is need for correlation among the various operating parameters such as stress, temperature and time. For individual components one normally uses empirical correlations such as Larson-Miller to predict rupture life and also creep growth. For assemblies in which relaxation is the main design issue, such parameters are usually not available. There is need to carry out detailed nonlinear analysis.
Typical bolted flange and shrink-fit assemblies are chosen for study. Parametric studies are carried out. Using creep properties as described earlier, nonlinear structural responses are studied. The purpose is to correlate the creep properties, in terms of creep strain with respect to time, stress and temperature, with the joint behavior. The key joint behavior indices are the bolt tensile stress in the case of threaded fastening and the compressive force of “effective interference” in the case of shrunk-fit assemblies.
The studies have established the need for rigorous creep analysis of components having interference fits or threaded fasteners. Once the operational requirements are known, the approach presented helps in material selection.
Numerical Simulation of Effects of Tip Geometry on the Performance of an Axial Compressor
Authors: Ma Hongwei , Zhang Jun 
Published: October 2013

The purpose of this paper is to investigate numerically the effects of the tip geometry on the performance of an axial compressor rotor. There are three case studies which are compared with the base line tip geometry. 1) baseline (flat tip); 2) Cavity (tip with a cavity); 3) SSQA (suction side squealer tip) and 4) SSQB (modified suction side squealer tip). The case of SSQB is a combination of suction side squealer tip and the cavity tip. From leading edge to 10% chord, the tip has a cavity. From 10% chord to trailing edge, the tip has a suction side squealer. The numerical results of 2) show that the cavity tip leads to lower leakage mass flow and greater loss in tip gap and the rotor passage. The loading near the blade tip is lower than the baseline, thus the tangential force of the blade is lower. It leads to lower pressure rise than the baseline. The performance of the compressor for the tip with cavity is worse than the baseline.
The results of 3) show that the higher curvature of the suction side squealer increases the loading of the blade and the tangential blade force. With the suction side squealer tip, the leakage flow experiences two vena contractor thus the mass of the leakage flow is reduced which is benefit for the performance of the compressor. The loss in the tip gap is lower than baseline. The performance is better than the baseline with greater pressure rise of the rotor, smaller leakage mass flow and lower averaged loss. For the case the SSQB, the leakage mass flow is lower than the SSQA and the loss in the tip gap and the rotor passage is greater than SSQA. The performance of the case of the SSQB is worse than the case of SSQA.
Form Factor for the Top-Level Comparison of the Condition of Supply of High-Pressure Compressor Blades
Authors: Schrade Marcus , Staudacher Stephan , Weißschuh Matthias , Voigt Matthias 
Published: October 2013

High-pressure compressor (HPC) performance and maintenance of gas turbines is influenced by blade production scatter and in-service deterioration. Complex geometries in HPC, especially at blades, yield to a large amount of component features, which individually influence performance and maintenance characteristics. This results in a highly complex and poorly observable system. Hence, the correlation of a single component feature to performance or maintenance characteristics is not purposeful and a reduction of the parameter space is advantageous.
A form factor is introduced that reduces geometric deviations of component features to a scalar. Principal component analysis (PCA) of measured HPC blades is used to support the form factor concept. The meaningfulness of this approach is shown in identifying process capabilities of different forges based on the form factor.
CFD Simulation of Steam Ejector System in High Altitude Test (HAT) Facility
Authors: Sreekireddy Pavani , Reddy T. Kishen Kumar , Dadi Venugopal , Bhramara P. 
Published: October 2013

In the present work, the performance of Steam Ejector System in High Altitude Test (HAT) facility is numerically studied, in the absence of the condenser. Steam is used as secondary fluid to eject the burnt gases into atmosphere.
Experimental visualization of mixing of burnt gas and steam and subsequent flow pattern is difficult, hence numerical simulation using FLUENT was done and the resulting flow stream lines, static and total pressures, shock patterns are computed along the ejector system to understand the physics of the problem. Three burnt gas flow rates of 9.17, 27.5 and 45.8 kg/s corresponding to lower, mid and upper limits of ejection from the HAT facility with the steam flow rate of 50 kg/s from Ejector I and 130 kg/s from Ejector II are studied. This corresponds to three cases of Entrainment Ratios for each of the ejector.
Results show that for a burnt gas flow rate of 27.5 and 45.8 kg/s with the given dimensions of the HAT facility provided by ASL, DRDO, the gas and steam start mixing in the converging duct, pass through the mixing tube and attains atmospheric pressure at the exit of the HAT facility. For the burnt gas flow rate of 9.17 kg/s, reverse flow is observed in the Ejector II, indicating the malfunction mode of the system for the given design parameters.