bluuebunny/crossref_metadata_2025_split huggingface dataset:
Candidate super star cluster progenitor gas clouds possibly triggered by close passage to Sgr A*
Authors: Longmore S. N. , Kruijssen J. M. D. , Bally J. , Ott J. , Testi L. , Rathborne J. , Bastian N. , Bressert E. , Molinari S. , Battersby C. , Walsh A. J. 
Published: May 2013

Abstract
Super star clusters are the end product of star formation under the most extreme conditions. As such, studying how their final stellar populations are assembled from their natal progenitor gas clouds can provide strong constraints on star formation theories. An obvious place to look for the initial conditions of such extreme stellar clusters is gas clouds of comparable mass and density, with no star formation activity. We present a method to identify such progenitor gas clouds and demonstrate the technique for the gas in the inner few hundred pc of our Galaxy. The method highlights three clouds in the region with similar global physical properties to the previously identified extreme cloud, G0.253 + 0.016, as potential young massive cluster (YMC) precursors. The fact that four potential YMC progenitor clouds have been identified in the inner 100 pc of the Galaxy, but no clouds with similar properties have been found in the whole first quadrant despite extensive observational efforts, has implications for cluster formation/destruction rates across the Galaxy. We put forward a scenario to explain how such dense gas clouds can arise in the Galactic Centre environment, in which YMC formation is triggered by gas streams passing close to the minimum of the global Galactic gravitational potential at the location of the central supermassive black hole, Sgr A*. If this triggering mechanism can be verified, we can use the known time interval since closest approach to Sgr A* to study the physics of stellar mass assembly in an extreme environment as a function of absolute time.
Effect of blast cleaning parameters on corrosion of brass parts
Authors: Masmoudi N. , Khlif M. 
Published: May 2013

PurposeThe purpose of this present work is to investigate how different parameters of the blast cleaning process affect properties and quality of brass parts surface. It aims to study the following process variables: particle abrasive shape: (spherical (S) and angular (G) shot), particle abrasive size (S170, G40 and G50) and the impact velocity (40 m/s, 60 m/s and 80 m/s).Design/methodology/approachAn experimental approach based on three testing methods is used to quantify the analysis of particulate contaminants on substrates surfaces. These methods are: SEM, BSEM and EDXA plots from SEM imaging.FindingsThe results obtained clearly show that the particle embedment decreases with decreasing of the size of angular abrasive. An increase in the embedment could be noted as impact velocity increased. It was also found that the angular abrasives have delivered a contamination level higher than that delivered by spherical abrasives. Furthermore, it was demonstrated that the abrasive debris nature embedded in the treated surfaces is the iron. The coupling of this debris with the base metal (copper) in the presence of wetland causes an electrochemical corrosion. Then, if the contamination level decreases, the corrosion rate in treated brass parts by steel shots decreases also.Originality/valueSearch in the case of blast cleaning for the brass parts by steel shots has not been done previously. Using the spherical shape of the abrasive projected with a moderate impact velocity will be a solution in this case.
Effect of size‐distributed bubbles on acoustic properties of an elastic tube with polymeric liquid
Authors: Levitsky Semyon , Bergman Rudolf , Haddad Jehuda 
Published: May 2013

PurposeThe objective of this study is to model the influence of free gas, in the form of size‐distributed fine bubbles, on sound attenuation and dispersion in a thin‐walled elastic cylindrical tube filled with viscoelastic polymeric liquid.Design/methodology/approachSound wave propagation in the system is described within a three‐phase interaction scheme, based on a quasi‐homogeneous approach to liquid‐gas mixture dynamics in the wave. Coupled equations of tube wall deformations and viscoelastic liquid dynamics in the tube are solved using a long‐wave approximation. The dissipative losses, stemming from flow gradients in the wave, as well as from non‐equilibrium bubble‐liquid interaction, are accounted for. The dispersion equation for the waveguide is obtained and studied numerically.FindingsThe results of the study indicate that bubble‐size distribution in viscoelastic liquid has an essential impact on sound propagation in the tube at sufficiently high frequencies. The frequency range in which the mixture heterogeneity influences the acoustic properties of the system is sensitive to both the distribution parameters and the rheological properties of the liquid. As distinct to polydispersity features, the viscoelastic properties of liquid are also relevant in the low‐frequency range, where they lead to an increase of the wave speed and a decrease of its attenuation.Originality/valueA model of sound wave propagation in a tube filled with a heterogeneous viscoelastic liquid‐bubble mixture is formulated. The study provides a basis for modeling transient processes in tubes filled with polymeric liquids containing free gas, and for acoustic control of certain processes in polymer technologies.
Performance study of various tool materials for electrical discharge machining of hot pressed ZrB2
Authors: Sivasankar S. , Jeyapaul R. , Bhanu Prasad V.V. 
Published: May 2013

PurposeThis study aims to explore the machinability of ZrB2 using electrical discharge machining (EDM) with different tool materials.Design/methodology/approachThe workpiece for this study was fabricated through powder metallurgy compaction method. The disc is machined using diamond load grinding to have parallel surfaces, then, 2 mm diameter holes are machined on the disc using EDM spark erosion machine with different tool materials (graphite, aluminium, tantalum, niobium, copper, brass, silver, tungsten and titanium). Roundness, geometry of hole, and diameter of the hole at different diametric planes, surface roughness (SR), material removal rate (MRR), tool wear rate (TWR), taper angle and recast layer (RCL) thickness are measured. The photographic analysis of tools, holes in the top view, bottom view and sectional view. SEM analysis was conducted to study the recast layer. Desirability function analysis was employed to rate the performances of tools.FindingsA new theory is developed which relates recast layer thickness with melting point and thermal conductivity of the tool materials. Machining of ZrB2 by EDM is feasible; graphite is identified as the best tool. Recast layer thickness of the machined surfaces are indirectly proportional to the product of melting point and thermal conductivity of tool. Ablation behaviour of ceramic workpiece lead additional material losses in the tool.Originality/valueExtremely high strength and hardness of ZrB2 due to the coexistence of strong covalent and metallic bond make mechanical machining very difficult or even impossible. No machinability studies were conducted previously on ZrB2 using EDM; this work reveals machinability study of ZrB2 with different tool materials.
Fluid‐structure interaction computational analysis of a piston‐cylinder based blast‐wave‐mitigation concept
Authors: Grujicic M. , Snipes J.S. , Chandrasekharan N. 
Published: May 2013

PurposeThis paper aims to utilize purpose advanced fluid‐structure interaction, non‐linear dynamics, finite‐element analyses in order to investigate various phenomena and processes accompanying blast wave generation, propagation and interaction and to assess the blast‐wave‐mitigation potential of a piston‐cylinder assembly placed in front of the target structure.Design/methodology/approachThe employed computational methods and tools are verified and validated by first demonstrating that they can quite accurately reproduce analytical solutions for a couple of well‐defined blast wave propagation and interaction problems.FindingsThe methods/tools are used to investigate the piston‐cylinder blast‐mitigation concept and the results obtained clearly reveal that significant blast‐mitigation effects can be achieved through the use of this concept. Furthermore, the results showed that the extent of the blast‐mitigation effect is a sensitive function of the piston‐cylinder geometrical parameters. Specifically, the mass of the piston and the length of the cylinder are found to be the dominant factors controlling the extent of the blast‐wave‐mitigation.Originality/valueThe work demonstrates that, when assessing the blast‐wave‐mitigation potential of the piston‐cylinder concept, it is critical that loading experienced by the piston be defined by explicitly modeling (fluid/structure) interactions between the blast wave(s) and the piston.
Changes in risk factors for preterm birth in Western Australia 1984–2006
Authors: Hammond G , Langridge A , Leonard H , Hagan R , Jacoby P , DeKlerk N , Pennell C , Stanley F 
Published: May 2013

ObjectiveTo characterise changing risk factors of preterm birth in Western Australia between 1984 and 2006.DesignPopulation‐based study.SettingWestern Australia.PopulationAll non‐Aboriginal women giving birth to live singleton infants between 1984 and 2006.MethodsMultinomial, multivariable regression models were used to assess antecedent profiles by preterm status and labour onset types (spontaneous, medically indicated, prelabour rupture of membranes [PROM]). Population attributable fraction (PAF) estimates characterized the contribution of individual antecedents as well as the overall contribution of two antecedent groups: pre‐existing medical conditions (including previous obstetric history) and pregnancy complications.Main outcome measureAntecedent relationships with preterm birth, stratified by labour onset type.ResultsMarked increases in maternal age and primiparous births were observed. A four‐fold increase in the rates of pre‐existing medical complications over time was observed. Rates of pregnancy complications remained stable. Multinomial regression showed differences in antecedent profiles across labour onset types. PAF estimates indicated that 50% of medically indicated preterm deliveries could be eliminated after removing six antecedents from the population; estimates for PROM and spontaneous preterm reduction were between 10 and 20%. Variables pertaining to previous and current obstetric complications (previous preterm birth, previous caesarean section, pre‐eclampsia and antepartum haemorrhage) were the most influential predictors of preterm birth and adverse labour onset (PROM and medically indicated).ConclusionsPreterm antecedent profiles have changed markedly over the 23 years studied. Some changes may be attributable to true change, others to advances in surveillance and detection. Still others may signify change in clinical practice.
Development of Novel Methods to Determine Crystalline Glucose Content of Honey Based on DSC, HPLC, and Viscosity Measurements, and Their Use to Examine the Setting Propensity of Honey
Authors: Al‐Habsi Nasser A. , Davis Fred J. , Niranjan Keshavan 
Published: May 2013

Abstract Crystallization must occur in honey in order to produce set or creamed honey; however, the process must occur in a controlled manner in order to obtain an acceptable product. As a consequence, reliable methods are needed to measure the crystal content of honey (ϕ expressed as kg crystal per kg honey), which can also be implemented with relative ease in industrial production facilities. Unfortunately, suitable methods do not currently exist. This article reports on the development of 2 independent offline methods to measure the crystal content in honey based on differential scanning calorimetry and high‐performance liquid chromatography. The 2 methods gave highly consistent results on the basis of paired t‐test involving 143 experimental points (P > 0.05, r2 = 0.99). The crystal content also correlated with the relative viscosity, defined as the ratio of the viscosity of crystal containing honey to that of the same honey when all crystals are dissolved, giving the following correlation: . This correlation can be used to estimate the crystal content of honey in industrial production facilities. The crystal growth rate at a temperature of 14 °C—the normal crystallization temperature used in practice—was linear, and the growth rate also increased with the total glucose content in the honey.
SP‐Designer: a user‐friendly program for designing species‐specific primer pairs from DNA sequence alignments
Authors: Villard Pierre , Malausa Thibaut 
Published: May 2013

AbstractSP‐Designer is an open‐source program providing a user‐friendly tool for the design of specific PCR primer pairs from a DNA sequence alignment containing sequences from various taxa. SP‐Designer selects PCR primer pairs for the amplification of DNA from a target species on the basis of several criteria: (i) primer specificity, as assessed by interspecific sequence polymorphism in the annealing regions, (ii) the biochemical characteristics of the primers and (iii) the intended PCR conditions. SP‐Designer generates tables, detailing the primer pair and PCR characteristics, and a FASTA file locating the primer sequences in the original sequence alignment. SP‐Designer is Windows‐compatible and freely available from http://www2.sophia.inra.fr/urih/sophia_mart/sp_designer/info_sp_designer.php.
Knockout of 5‐lipoxygenase prevents dexamethasone‐induced tau pathology in 3xTg mice
Authors: Joshi Yash B. , Chu Jin , Praticò Domenico 
Published: May 2013

SummaryEmerging evidence suggests that dysregulation stress hormones, such as glucocorticoids, in aged persons put them at a higher risk to develop Alzheimer's disease (AD). However, the mechanisms underlying such vulnerability remain to be unraveled. Pharmacologic inhibition of 5‐lipoxygenase (5LO), an active player in AD pathogenesis whose protein level increases with aging in the human, has been shown to blunt glucocorticoid‐mediated amyloid β (Ab) formation in vitro. In this article, we investigated the role of this pathway in modulating the development of the corticosteroid‐dependent AD‐like phenotype in the triple transgenic mice (3xTg). Dexamethasone was administered for 1 week to 3xTg or 3xTg genetically deficient for 5LO (3xTg/5LO−/−) mice, and its effect on memory, amyloid‐β and tau levels, and metabolism assessed. At the end of the treatment, we observed that dexamethasone did not induce changes in behavior. Compared with controls, treated mice did not show significant alterations in brain soluble Aβ levels. While total tau protein levels were unmodified in all groups, we found that dexamethasone significantly increased tau phosphorylation at S396, as recognized by the antibody PHF‐13, which was specifically associated with an increase in the GSK3β activity. Additionally, dexamethasone‐treated mice had a significant increase in the tau insoluble fraction and reduction in the postsynaptic protein PDS‐95. By contrast, these modifications were blunted in the 3xTg/5LO−/− mice. Our findings highlight the functional role that 5LO plays in stress‐induced AD tau pathology and support the hypothesis that pharmacologic inhibition of this enzyme could be a useful tool for individuals with this risk factor.
Evaluation of Suction Detection During Different Pumping States in an Implantable Rotary Blood Pump
Authors: Ng Siew‐Cheok , Lim Einly , Mason David G. , Avolio Alberto P. , Lovell Nigel H. 
Published: May 2013

AbstractIn recent times, the problem of noninvasive suction detection for implantable rotary blood pumps has attracted substantial research interest. Here, we compare the performance of various suction indices for different types of suction and non‐suction events based on pump speed irregularity. A total of 171 different indices that consist of previously proposed as well as newly introduced suction indices are tested using regularized logistic regression. These indices can be classified as amplitude based (derived from the mean, maximum, and minimum values of a cycle), duration based (derived from the duration of a cycle), gradient based (derived from the first order as well as higher order differences) and frequency based (derived from the power spectral density). The non‐suction event data consists of ventricular ejection with or without arrhythmia and intermittent and continuous non‐opening of the aortic valve. The suction event data consists of partial ventricular collapse that occurs intermittently as well as continuously with or without arrhythmia. In addition, we also attempted to minimize the usage of multiple indices by applying the sequential forward floating selection method to find which combination of indices gives the best performance. In general, the amplitude‐based and gradient‐based indices performed quite well while the duration‐based and frequency‐based indices performed poorly. By having only two indices ([i] the maximum gradient change in positive slope; and [ii] the standard deviation of the maximum value in a cycle), we were able to achieve a sensitivity of 98.9% and a specificity of 99.7%.
Dyslipidemia Is Associated With Tunneled‐Cuffed Catheter‐Related Central Venous Thrombosis in Hemodialysis Patients: A Retrospective, Multicenter Study
Authors: Cheng Yuan , Cui Tianlei , Fu Ping , Liu Fang , Zhou Li 
Published: May 2013

AbstractThe aim of this study was to explore the risk factors of tunneled‐cuffed catheter (TCC)‐related central venous thrombosis (CVT) for the maintenance of hemodialysis patients. In this study, 285 patients on maintenance hemodialysis were enrolled who had received their first TCC in the right jugular vein. Patients were divided into CVT and control groups according to the diagnosis of TCC‐related CVT 6 months after catheterization. Patients with CVT had a higher prevalence of dyslipidemia (50.74 vs. 26.85%, respectively) and low protein store compared with the control group. After adjusting for confounders, serum triglycerides (OR: 3.632; 95% CI: 2.105–6.267), non‐HDL cholesterol (OR: 1.463; 95% CI:1.067–2.007), and low‐density lipoprotein/high‐density lipoprotein (LDL/HDL) cholesterol ratio (OR: 2.904; 95% CI: 1.797–4.692) were positively correlated with TCC‐related CVT, while serum HDL cholesterol (OR: 0.097; 95% CI: 0.037–0.257) and serum albumin (OR: 0.922; 95% CI: 0.864–0.985) were negatively correlated. Dyslipidemia and low serum albumin levels were significantly associated with TCC‐related CVT in hemodialysis patients.
Effects of exclusive breastfeeding intervention on child growth and body composition: theMINIMat trial,Bangladesh
Authors: Khan Ashraful I , Hawkesworth Sophie , Ekström Eva‐Charlotte , Arifeen Shams , Moore Sophie E , Frongillo Edward A , Yunus Md , Persson Lars Å , Kabir Iqbal 
Published: May 2013

AbstractAimExclusive breastfeeding (EBF) for 6 months is recommended for optimal infant health, but the evidence for longer‐term impacts is weak. We examined whether randomization to receiveEBFcounselling (BFC) in ruralBangladeshi women had an impact on childhood growth trajectories and body composition.MethodsIn the Maternal and Infant Nutrition Interventions in Matlab trial, 4436 pregnant women were randomized to six equally sized, food and micronutrient groups. Of these, 3214 were randomized during the last trimester of pregnancy to receive eitherBFCor the usual/standard health message (UHM). Their infants were extensively followed up, with anthropometric measurements between 0 and 54 months and assessment of body composition at 54 months.ResultsThe mean duration ofEBFin theBFCgroup was 111 days compared to 76 days in theUHMgroup (mean difference: 35.0 days, 95%CI30.6–39.5, p < 0.001). There was no difference in growth trajectories between theBFCandUHMgroups and no difference in body composition at 54 months. Children exposed to prenatal multiple micronutrients (vs 60 mg iron and folate) combined withBFC(vsUHM), however, had slower linear growth (mean difference −0.17SDscore, p < 0.01).ConclusionExclusive breastfeeding counselling resulted in neither differential growth trajectories in infancy and childhood, nor body composition differences at 54 months. The combination of prenatal multiple micronutrient supplementation (MMS) andBFCwas unfavourable for linear growth during 0–54 months, which raises questions about possible negative effects ofMMS.
INCENTIVE AND INSURANCE EFFECTS OF INCOME TAXATION
Authors: Andersen Torben M. 
Published: May 2013

ABSTRACTTax distortions cause a trade‐off between efficiency and equity. However, taxes not only affect incentives; they also provide implicit insurance, and this may critically affect the efficiency–equity relationship. For a standard labour supply problem it is shown that the insurance effect mutes the sensitivity of labour supply to taxes, which tends to reduce tax distortions and lower the marginal costs of public funds. The relation between incentives and insurance and thus efficiency and equity is flattened by the insurance effect and it may even be non‐monotone. However, the optimal utilitarian policy implies that there is always a trade‐off between efficiency and equity on the margin.
NKG2D blockade attenuated cardiac allograft vasculopathy in a mouse model of cardiac transplantation
Authors: Chen H , Xia J , Zhang L , Jin X , Yang M , Li J , Zhao Y 
Published: May 2013

SummaryA previous paper has reported that blockade of NKG2D was effective in protecting allograft in murine models of cardiac transplantation, but the mechanism of NKG2D blockade on attenuated cardiac allograft vasculopathy (CAV) was still unknown. In our current study, we found that wild-type recipients treated with anti-NKG2D monoclonal antibody (mAb) plus cytotoxic T lymphocyte antigen (CTLA)-4-immunoglobulin (I)g showed prolonged allograft survivals (&gt;90 days, P &lt; 0·001) significantly and attenuated CAV. These in-vivo results correlated with reduced alloantibody production, low expression of interleukin (IL)-17 and IL-6, while infiltration of regulatory T cells increased. IL-6 administration induced shorter allograft survival and higher CAV grade in CTLA-4–Ig plus anti-NKG2D mAb-treated recipients, whereas IL-17 had no significant effect on allograft survival and CAV grade in CTLA-4–Ig plus anti-NKG2D mAb-treated recipients. Furthermore, the prolonged allograft survival induced by NKG2D blockade was abrogated partially with depletion of regulatory T cells. In conclusion, blockade of NKG2D combined with CTLA-4–Ig attenuated CAV and this effect was associated with lower alloantibody production, inhibited IL-6 expression and enhanced expansion of regulatory T cells.