400 research outputs found

    Coevolution of metallicity and star formation in galaxies to z=3.7: I. A fundamental plane

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    With the aim of understanding the coevolution of star formation rate (SFR), stellar mass (M*), and oxygen abundance (O/H) in galaxies up to redshift z=3.7, we have compiled the largest available dataset for studying Metallicity Evolution and Galaxy Assembly (MEGA); it comprises roughly 1000 galaxies with a common O/H calibration and spans almost two orders of magnitude in metallicity, a factor of 10^6 in SFR, and a factor of 10^5 in stellar mass. From a Principal Component Analysis, we find that the 3-dimensional parameter space reduces to a Fundamental Plane of Metallicity (FPZ) given by 12+log(O/H) = -0.14 log (SFR) + 0.37 log (M*) + 4.82. The mean O/H FPZ residuals are small (0.16 dex) and consistent with trends found in smaller galaxy samples with more limited ranges in M*, SFR, and O/H. Importantly, the FPZ is found to be redshift-invariant within the uncertainties. In a companion paper, these results are interpreted with an updated version of the model presented by Dayal et al. (2013).Comment: 19 pages, 10 figures, 4 tables, accepted for publication in MNRA

    Aerodynamic Optimisation of a Morphing Leading Edge Airfoil

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    A morphing leading edge airfoil is optimized for aerodynamic performance with different objectives. A constant arc length parameterization employing the Class/Shape Transformation technique is built to limit the axial deformation introduced by morphing. The optimization is performed with a standard methodology based on genetic algorithms, comparing the results for three different aerodynamic models: a potential flow solver with boundary layer calculation (XFOIL), a fully turbulent RANS model (Spalart-Allmaras) and a transitional RANS model (gamma-theta). Whereas the solutions obtained with the third model are standard droop nose shapes, those found via transitional models show an uncommon deformation with an upward leading edge deflection. Development of optimization strategy is also performed by building an hybrid procedure based on a metamodel-assisted approach. Several nonlinear regression methods are investigated to compare the accuracy in fitness approximation and an Artificial Neural Network (ANN) was finally selected. Application of the improved algorithm to a probelm previously solved with a standard approach shows that the use of a surrogate model, combined with a gradient based method for local individual improvement, is able to provide a reduction of the convergence effort when approximating the highly nonlinear relationship between the constant arc length parameterization and the aerodynamic behavior predicted with gamma-theta model

    The Effect of \u3cem\u3eACP1-ADA1\u3c/em\u3e Genetic Interaction on Human Life Span

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    Acid phosphatase (ACP1) is a polymorphic enzyme which catalyzes the conversion of flavinmononucleotide (FMN) to riboflavin and regulates the cellular concentration of flavin-adeninedinucleotide (FAD) and, consequently, energy metabolism. Its activity is modulated by adenosine deaminase (ADA1) genotype. Aim of our work is to verify whether individuals with a high proportion of ACP1 f isozyme and carrying ADA*2 allele, displaying the highest phosphatase activity, may have a higher life expectancy. Genomic DNA was extracted from peripheral blood of 569 females and 509 males (18-106 years) randomly recruited from Central Italy. These samples were subdivided into three sexspecific age groups (the ages of women are in square bracket): Class 1:age \u3c66 [\u3c73]; Class 2: age 66-88 [73-91]; Class 3: age \u3e88 [\u3e91]. ACP1 and ADA1 SNPs were genotyped by RFLP-PCR methods and statistical analyses were performed using SPSS 14.0. The results showed a larger proportion of Class 3 individuals displaying high ACP1 f isozyme concen ration and carrying ADA1*2 allele than those of Class 2 and Class 2+1. Thus, we postulate that in Class 3 individuals the high phosphatase activity, resulting from the combined presence of high ACP1 f isozyme concentration and the ADA1*2 allele, lowers the rate of glycolysis which may reduce the amount of metabolic calories and, in turn, activate Sirtuin genes that protect cells against age-related diseases

    Do coxibs reduce prescription of gastroprotective agents? Results of a record linkage study

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    BACKGROUND: Coxibs are claimed to be cost-effective drugs and reduced prescription of gastroprotective agents is assumed to be one of their major benefits. Real life prescription of these drugs may be substantially different than that considered in pharmacoeconomic analyses or claimed by drug companies, yet. Our objective was to evaluate whether coxibs were associated with reduced prescription of gastro-protective agents (GPAs, specifically proton pump inhibitors, H(2 )blockers and misoprostol) compared to non selective NSAIDs. METHODS: A record-linkage study was performed using 2001 outpatient prescription data from the province of Modena (about 632,000 inhabitants, in Northern Italy). Logistic regression was used to calculate the odds ratio of GPA prescription for coxib and non-selective NSAID adult users (> 14 years). Three categories of users were further investigated: "acute", "chronic and "incident or new". Main outcome measures were same-day co-prescription and 30 days prescription of GPAs in coxibs and non selective NSAIDs users. To limit selection bias, data were adjusted for age, sex, DDD of coxibs and non selective NSAIDs received during 2001, DDD of GPAs and (for non-incident users) DDD of NSAIDs received during the previous 4 years RESULTS: Same day co-prescription rates were similar considering the overall population and "acute" users. Chronic coxibs users instead showed higher co-prescription rates than chronic NSAIDs users (OR = 1.2, p < 0.05). GPA prescription within thirty days was also higher among all subgroups of coxibs users (OR ranging from 1.6 to 2.0, p < 0.001). CONCLUSION: Assumptions made in pharmacoeconomic analyses on coxibs (lower GPA prescription associated with coxibs use) may be overly optimistic. Claims made through cost-effectiveness data should be carefully interpreted, and mechanisms for attributing drug prices revised accordingly

    Significant relationship of combined ACP1/PTPN22 genotype variants with the growth of uterine leiomyomas

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    Objective: To analyze the interaction between ACP1 and PTPN22 concerning their effects on the growth of the tumor. In previous paper we have shown (i) that ACP1*B/*B genotype of ACP1 is negatively associated with the growth of leiomyomas and (ii) that there is a negative association of *C/*C genotype of PTPN22 with tumor growth. Materials and methods: Two hundred and three White women from the population of Rome with symptomatic leiomyomas were recruited in the University of Rome Tor Vergata. All subjects gave consent for the participation in the study that was approved by the Council of Department. ACP1 and PTPN22 genotypes were determined by DNA analysis. Results: The proportion of women with small leiomyomas decreases with the decrease of the number of protective factors and it is 37.2% in women carrying the joint genotype ACP1*B/*B-PTPN22 *C/*C (two protective factors) and 0% in women carrying no protective factors. Three way contingency table analysis by a log linear model has shown no evidence of epistatic interaction between the two genetic systems but a highly significant cooperative effect on the dimension of leiomyomas. There is a highly significant negative correlation between the number of protective factors and the dimension of leiomyomas with a minimum (cm 4.74) in women carrying the joint genotype ACP1*B/B-PTPN22 *C/*C and a maximum (cm 7.25) in women carrying no protective factors. Conclusion: The present study suggests a cooperative interaction between ACP1 and PTPN22 concerning their effects on the growth of uterine leiomyomas. The determination of the genotype of the two systems may help to evaluate the risk of clinical manifestations of this common benign tumor. Keywords: ACP1, PTPN22, Uterine leiomyoma

    Thermally-Reconfigurable Quantum Photonic Circuits at Telecom Wavelength by Femtosecond Laser Micromachining

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    The importance of integrated quantum photonics in the telecom band resides on the possibility of interfacing with the optical network infrastructure developed for classical communications. In this framework, femtosecond laser written integrated photonic circuits, already assessed for quantum information experiments in the 800 nm wavelength range, have great potentials. In fact these circuits, written in glass, can be perfectly mode-matched at telecom wavelength to the in/out coupling fibers, which is a key requirement for a low-loss processing node in future quantum optical networks. In addition, for several applications quantum photonic devices will also need to be dynamically reconfigurable. Here we experimentally demonstrate the high performance of femtosecond laser written photonic circuits for quantum experiments in the telecom band and we show the use of thermal shifters, also fabricated by the same femtosecond laser, to accurately tune them. State-of-the-art manipulation of single and two-photon states is demonstrated, with fringe visibilities greater than 95%. This opens the way to the realization of reconfigurable quantum photonic circuits on this technological platform

    Augmented Interaction Systems for Supporting Autistic Children. Evolution of a Multichannel Expressive Tool: The SEMI Project Feasibility Study

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    International audienceBackground: Over the past ten years, the authors have been designing, developing, and testing pervasive technology to support children with autism (ASD). Methods: In the present study, an integrated system based on multimedia and augmented interaction technologies have been tested on young subjects with ASD and dyspraxia in the age range of 6-10 years, in charge for rehabilitation treatments; a team of clinical psychologists has analyzed the results of the experimentation. The ten children involved in the project underwent an initial assessment of praxis skills and motor coordination. Subsequently, the subjects were subdivided into two subgroups: five children participated in the experimentation and five were evaluated as the control group (treatment as usual). Results: The evaluation showed an increased score in the several aspects considered, and particularly those related to motor coordination. An improvement in balancing tests and in hands-movement testing was found. Conclusion: The children involved in the sessions showed greater ability to self-control the movement as well as to select specific motor areas. The methods used seem to be promising to improve emotional and social skills too in a motivating and enjoyable climate. A high level of acceptance by professionals was observed and parents' feedback was also positive

    Correlation between birth weight and placental weight in healthy and diabetic puerperae

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    Abstract Objective The birth weight/placental weight ratio has an important predictive value for perinatal mortality and morbidity and for cardiovascular diseases in adult life. In this study, we compared the birth weight/placental weight (BW/PW) ratio and the correlation between the two parameters in diabetic women with that observed in healthy women. Materials and Methods A total of 347 consecutive newborn infants from healthy puerperae, 164 newborns from puerperae with gestational diabetes, 148 newborns from puerperae with preexisting type 1 diabetes, and 40 newborns from puerperae with preexisting type 2 diabetes have been studied from the White population of Rome. The research project was approved by the Institutional Review Board and informed written consent was obtained from the participating mothers. Results The BW/PW ratio is higher, and the correlation between the two parameters is lower in all classes of diabetes as compared to healthy puerperae. A remarkably low correlation is observed in preexisting diabetes pointing to a dissociation of fetal growth from placental growth. Discussion In diabetic pregnancy the BW/PW ratio is higher, and the correlation between birth weight and placental weight is lower in all classes of diabetic as compared to healthy puerperae pointing to a relative dissociation between the two parameters. It has been suggested that the increase of glycemic levels in diabetic pregnancy predisposes to important diseases in adult life. The dissociation of BW from PW in infants of diabetic pregnancy could be a predictor of the risk for such diseases of adult life
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