263 research outputs found

    An experimental study on adsorption characteristics of r134a and r404a onto silicagel adsorbents

    Get PDF
    The objective of this study is to evaluate adsorption characteristics of R134a and R404a on commercially available silica gel samples. A constant volume variable pressure method at different adsorption temperatures ranging from 293 to 323 K and for pressures up to 500 kPa is used in the experimental measurements. Three different type of commercially available silica gel samples were chosen as adsorbent. The isotherms obtained from the experimental measurements were presented. Adsorption parameters were evaluated from the isotherms in order to obtain correlations in the form of the Dubinin-Astakhov (DA) equation. The pressure and temperature dependence of the isosteric enthalpies of adsorption is computed with the evaluation of the measured data and the derived equations. Further, the enthalpy of adsorption data were extracted, and correlations are provided for adsorbent-adsorbate pairs obtained from the combinations of the three different silica gel specimens and two refrigerants.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

    Using photonic crystals for structural coloration of textiles

    Get PDF
    In this work, poly (styrene-methyl methacrylate-acrylic acid) P(St-MMA-AA) composite nanospheres were deposited on the woven cotton fabrics. The deposited photonic crystals on the fabrics were evaluated for coating efficiency and resistance, chemical analysis and color variation by optical and SEM microscopy, ATR-FTIR, diffuse reflectance spectroscopy and washing fastness. The photonic nanospheres show an average diameter of 280 nm and display a face centre cubic (FCC) with an average thickness of 10 µm.This work is supported by FEDER funding on the COMPETE program and by national funds through FCT-Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007136 and UID/CTM/00264.info:eu-repo/semantics/acceptedVersio

    Ordering ambiguity revisited via position dependent mass pseudo-momentum operators

    Get PDF
    Ordering ambiguity associated with the von Roos position dependent mass (PDM) Hamiltonian is considered. An affine locally scaled first order differential introduced, in Eq.(9), as a PDM-pseudo-momentum operator. Upon intertwining our Hamiltonian, which is the sum of the square of this operator and the potential function, with the von Roos d-dimensional PDM-Hamiltonian, we observed that the so-called von Roos ambiguity parameters are strictly determined, but not necessarily unique. Our new ambiguity parameters' setting is subjected to Dutra's and Almeida's [11] reliability test and classified as good ordering.Comment: 10 pages, no figures, revised/expanded, mathematical presentations in section 2 (Especially, the typological Errors in Eqs.(9)-(12))are now corrected. To appear in the Int. J. Theor. Phy

    Immigrant community integration in world cities

    Full text link
    As a consequence of the accelerated globalization process, today major cities all over the world are characterized by an increasing multiculturalism. The integration of immigrant communities may be affected by social polarization and spatial segregation. How are these dynamics evolving over time? To what extent the different policies launched to tackle these problems are working? These are critical questions traditionally addressed by studies based on surveys and census data. Such sources are safe to avoid spurious biases, but the data collection becomes an intensive and rather expensive work. Here, we conduct a comprehensive study on immigrant integration in 53 world cities by introducing an innovative approach: an analysis of the spatio-temporal communication patterns of immigrant and local communities based on language detection in Twitter and on novel metrics of spatial integration. We quantify the "Power of Integration" of cities --their capacity to spatially integrate diverse cultures-- and characterize the relations between different cultures when acting as hosts or immigrants.Comment: 13 pages, 5 figures + Appendi

    Genetic findings in short Turkish children born to consanguineous parents

    Get PDF
    IntroductionThe diagnostic yield of genetic analysis in the evaluation of children with short stature depends onassociated clinical characteristics, but the additional effect of parental consanguinity has not beenwell documented.MethodsThis observational case series of 42 short children from 34 consanguineous families was collected bysix referral centres of paediatric endocrinology (inclusion criteria: short stature and parentalconsanguinity). In eighteen patients (12 families, Group 1), the clinical features suggested a specificgenetic defect in the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis, and a candidategene approach was used. In others (Group 2) a hypothesis-free approach was chosen (gene panels,microarray analysis, and whole-exome sequencing), further subdivided into 11 patients with severeshort stature (height <-3.5 SDS) and microcephaly (head circumference <-3.0 SDS) (group 2a), 10patients with syndromic short stature (group 2b) and were 3 patients with nonspecific isolated GHdeficiency (group 2c).ResultsIn all 12 families from group 1, (likely) pathogenic variants were identified in GHR, IGFALS, GH1, andSTAT5B. In 9/12 families from group 2a, variants were detected in PCNT, SMARCAL1, SRCAP, WDR4and GHSR. In 5/9 families from group 2b, variants were found in TTC37, SCUBE3, NSD2, RABGAP1,and 17p13.3 microdeletions. In group 2c no genetic cause was found. Homozygous, compoundheterozygous and heterozygous variants were found in 21, 1 and 4 patients, respectively.ConclusionGenetic testing in short children from consanguineous parents has a high diagnostic yield, especiallyin cases of severe GH deficiency or insensitivity, microcephaly, and syndromic short stature

    Modulation of γ-Secretase Reduces β-Amyloid Deposition in a Transgenic Mouse Model of Alzheimer's Disease

    Get PDF
    SummaryAlzheimer's disease (AD) is characterized pathologically by the abundance of senile plaques and neurofibrillary tangles in the brain. We synthesized over 1200 novel gamma-secretase modulator (GSM) compounds that reduced Aβ42 levels without inhibiting epsilon-site cleavage of APP and Notch, the generation of the APP and Notch intracellular domains, respectively. These compounds also reduced Aβ40 levels while concomitantly elevating levels of Aβ38 and Aβ37. Immobilization of a potent GSM onto an agarose matrix quantitatively recovered Pen-2 and to a lesser degree PS-1 NTFs from cellular extracts. Moreover, oral administration (once daily) of another potent GSM to Tg 2576 transgenic AD mice displayed dose-responsive lowering of plasma and brain Aβ42; chronic daily administration led to significant reductions in both diffuse and neuritic plaques. These effects were observed in the absence of Notch-related changes (e.g., intestinal proliferation of goblet cells), which are commonly associated with repeated exposure to functional gamma-secretase inhibitors (GSIs)

    Risk Prediction Scores for Recurrence and Progression of Non-Muscle Invasive Bladder Cancer: An International Validation in Primary Tumours

    Get PDF
    Abstract Objective: We aimed to determine the validity of two risk scores for patients with non-muscle invasive bladder cancer in different European settings, in patients with primary tumours. Methods: We included 1,892 patients with primary stage Ta or T1 non-muscle invasive bladder cancer who underwent a transurethral resection in Spain (n = 973), the Netherlands (n = 639), or Denmark (n = 280). We evaluated recurrence-free survival and progression-free survival according to the European Organisation for Research and Treatment of Cancer (EORTC) and the Spanish Urological Club for Oncological Treatment (CUETO) risk scores for each patient and used the concordance index (c-index) to indicate discriminative ability. Results: The 3 cohorts were comparable according to age and sex, but patients from Denmark had a larger proportion of patients with the high stage and grade at diagnosis (p,0.01). At least one recurrence occurred in 839 (44%) patients and 258 (14%) patients had a progression during a median follow-up of 74 months. Patients from Denmark had the highest 10- year recurrence and progression rates (75% and 24%, respectively), whereas patients from Spain had the lowest rates (34% and 10%, respectively). The EORTC and CUETO risk scores both predicted progression better than recurrence with c-indices ranging from 0.72 to 0.82 while for recurrence, those ranged from 0.55 to 0.61. Conclusion: The EORTC and CUETO risk scores can reasonably predict progression, while prediction of recurrence is more difficult. New prognostic markers are needed to better predict recurrence of tumours in primary non-muscle invasive bladder cancer patients.This research received funding from the European Community's Seventh Framework program FP7/2007-2011 under grant agreement 201663 (Uromol project, http://www.uromol.eu/

    Plasma Brain-Derived Neurotrophic Factor Levels Predict the Clinical Outcome of Depression Treatment in a Naturalistic Study

    Get PDF
    Remission is the primary goal of treatment for major depressive disorder (MDD). However, some patients do not respond to treatment. The main purpose of this study was to determine whether brain-derived neurotrophic factor (BDNF) levels are correlated with treatment outcomes. In a naturalistic study, we assessed whether plasma BDNF levels were correlated with clinical outcomes by measuring plasma BDNF in patients with depressive syndrome (MADRS score ≥18), and subsequently comparing levels between the subgroup of patients who underwent remission (MADRS score ≤8) and the subgroup who were refractory to treatment (non-responders). Patients with depressive syndrome who underwent remission had significantly higher plasma BDNF levels (p<0.001), regardless of age or sex. We also found a significant negative correlation between MADRS scores and plasma BDNF levels within this group (ρ = –0.287, p = 0.003). In contrast, non-responders had significantly lower plasma BDNF levels (p = 0.029). Interestingly, plasma BDNF levels in the non-responder group were significantly higher than those in the remission group in the initial stage of depressive syndrome (p = 0.002). Our results show that plasma BDNF levels are associated with clinical outcomes during the treatment of depression. We suggest that plasma BDNF could potentially serve as a prognostic biomarker for depression, predicting clinical outcome
    corecore