6,645 research outputs found
Design and development of a multipurpose, boresighted star tracker
Design and development of boresighted star tracke
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Quantum spin Hall effect in bound states in continuum
Moving the polarization of the incident wave along a meridian of the Poincaré sphere, experimentally we show that the coupling with the fundamental Bloch's surface waves of the mode, provide a spatially coherent, macroscopic spinmomentum locked propagation along the symmetry axes of the PhCM. This novel mechanism of light-spin manipulation enables a versatile implementation of spin-optical structures that may pave the way to novel strategies for light spin technology and photonic multiplatform implementations
POTENTIAL DEMAND AND PRELIMINARY DESIGN OF DOOR TO DOOR DIAL A RYDE SYSTEMS
The paper aims to provide a framework for the preliminary design of dial a ride system. In this context we have carried out a stated preference survey to evaluate the potential
demand of service, taking into account a sample of citizens with limited disability to move.
Thus, we have submitted a questionnaire to users of some clinics of Palermo, considering in
the choice competitive scenario the dial a ride system. Furthermore a multinomial logit model
has been calibrated. Finally a preliminary design of service has been proposed
Bus speed estimation by neural networks to improve the automatic fleet management
In the urban areas, public transport service interacts with the private mobility. Moreover, on each link
of the urban public transport network, the bus speed is affected by a high variability over time. It depends
on the congestion level and the presence of bus way or no. The scheduling reliability of the public
transport service is crucial to increase attractiveness against private car use. A comparison between a
Radial Basis Function network (RBF) and Multi layer Perceptron (MLP) was carried out to estimate the
average speed, analysing the dynamic bus location data achieved by an AVMS (Automatic Vehicle
Monitoring System). Collected data concern bus location, geometrical parameters and traffic conditions.
Public Transport Company of Palermo provided these data
MULTIPLE PLURIPOTENT STEM CELL MARKERS IN HUMAN ANAPLASTIC THYROID CANCER: THE PUTATIVE UPSTREAM ROLE OF SOX-2
Background: Anaplastic Thyroid Carcinoma (ATC) is a rare and aggressive endocrine tumor, with highly undifferentiated morphology. It has been suggested that cancer stem cells (CSCs) might play a central role in ATC. The objectives of this study were the following: 1) to characterize CSCs from ex vivo ATC specimens by investigating the expression of several pluripotent stem cell markers; 2) to evaluate in vitro drug resistance modifications after specific CSC transcription factor switch off. Methods: Ex vivo: eight formalin-fixed, paraffin-embedded ATC specimens were analyzed by RT and qRT-PCR and immunohistochemistry. In vitro: in ATC SW1736 cells the expression levels of OCT-4, NANOG and ABCG2 and the sensitivity to either cisplatin or doxorubicin were evaluated after silencing. Results: OCT-4, KLF4 and SOX2 transcription factors and C-KIT and THY-1 stem surface antigens showed variable up-regulation in all ATC cases. The SW1736 cell line was characterized by a high percentage of stem population (10.4 \ub1 2.1 % of cells were aldehyde dehydrogenase positive) and a high expression of several CSC markers (SOX2, OCT4, NANOG, C-MYC, SSEA4). SOX2 silencing down-regulated OCT-4, NANOG and ABCG2. SOX2 silencing sensitized SW1736 cells, causing a significant cell death increase (1.8 fold) in comparison to control cells with 10 \ub5M cisplatin (93.9\ub13.4% vs. 52.6\ub19.4%, p<0.01) and 2.7 fold with 0.5\ub5M doxorubicin (45.8\ub19.9% vs. 17.1\ub13.4% p<0.01). ABCG2 silencing caused increased cell death with both cisplatin (74.9\ub11.4%) and doxorubicin treatment (74.1\ub10.1%) vs. no-target-treated cells (respectively, 45.8\ub11.0% and 48.6\ub11.0%, p<0.001). Conclusions: The characterization of CSCs in ATC through the analysis of multiple pluripotent stem cell markers might be useful in identifying cells with a stem-like phenotype capable of resisting conventional chemotherapy. In addition, our data demonstrate that SOX2 switch-off through ABCG2 transporter down-regulation has a major role in overcoming CSC chemotherapy resistance
Ketogenic diet-induced weight loss is associated with an increase in vitamin d levels in obese adults
Vitamin D is an important micronutrient involved in several processes. Evidence has shown a strong association between hypovitaminosis D and cardio-metabolic diseases, including obesity. A ketogenic diet has proven to be very effective for weight loss, especially in reducing fat mass while preserving fat-free mass. The aim of this study was to investigate the effect of a ketogenic diet-induced weight loss on vitamin D status in a population of obese adults. We enrolled 56 obese outpatients, prescribed with either traditional standard hypocaloric Mediterranean diet (SHMD) or very low-calorie ketogenic diet (VLCKD). Serum 25(OH)D concentrations were measured by chemiluminescence. The mean value of serum 25-hydroxyvitamin D (25(OH)D) concentrations in the whole population at baseline was 17.8 +/- 5.6 ng/mL, without differences between groups. After 12 months of dietetic treatment, in VLCKD patients serum 25(OH)D concentrations increased from 18.4 +/- 5.9 to 29.3 +/- 6.8 ng/mL (p < 0.0001), vs 17.5 +/- 6.1 to 21.3 +/- 7.6 ng/mL (p = 0.067) in the SHMD group (for each kilogram of weight loss, 25(OH)D concentration increased 0.39 and 0.13 ng/mL in the VLCKD and in the SHMD groups, respectively). In the VLCKD group, the increase in serum 25(OH)D concentrations was strongly associated with body mass index, waist circumference, and fatty mass variation. In a multiple regression analysis, fatty mass was the strongest independent predictor of serum 25(OH)D concentration, explaining 15.6%, 3.3%, and 9.4% of its variation in the whole population, in SHMD, and VLCKD groups, respectively. We also observed a greater reduction of inflammation (evaluated by high-sensitivity C reactive protein (hsCRP) values) and a greater improvement in glucose homeostasis, confirmed by a reduction of HOMA values, in the VLCKD versus the SHMD group. Taken together, all these data suggest that a dietetic regimen, which implies a great reduction of fat mass, can improve vitamin D status in the obese
The Effect of Advanced Traveller Information Systems (ATIS) on public transport demand and its uncertainty
Advanced Traveller Information Systems (ATISs) include a broad range of advanced computer and communication technologies. These systems are designed to provide transit riders pre-trip and real-time information, to make better
informed decisions regarding their mode of travel, planned routes and travel times. ATISs include in-vehicle displays, terminal or wayside based information centres, information by phone or mobile and internet. In this article, a Stated
Preference survey has been carried out in order to know the preferences of public transport\u2019s customers related to different ATISs and their willingness to pay in Palermo. An ordered probit demand model has been calibrated to determine the potential additional share of demand attracted by the adoption of ATISs. Finally, Monte Carlo simulation has been carried out to appraise the uncertainty on some parameters of the calibrated demand model. The results show that respondents give more importance to the type of information and its cost, whereas they are less interested in the system that provides the information
Effects of dopamine infusion on forearm blood flow in critical patients.
Piazza O, Zito G, Valente A, Tufano R.
Effects of dopamine infusion on forearm blood flow in critical patients.
Med Sci Monit. 2006 Feb;12(2):CR90-3. Epub 2006 Jan 26
Immunity, Inflammation and Heart Failure: Their Role on Cardiac Function and Iron Status
Aims: Heart failure is a clinical syndrome characterized by subclinical systemic inflammation and immune system activation associated with iron deficiency. No data exist on the various activations of immune-mediated mechanisms of inflammation in heart failure patients with reduced/preserved ejection fraction. We aimed to (1) investigate possible differences in inflammatory parameters and oxidative stress, and (2) detect a different iron status between groups. Materials and Methods: We enrolled 50 consecutive Caucasian outpatients with heart failure. All patients underwent echocardiographic measurements, laboratory determinations, evaluation of iron status and Toll-like receptors, and NF-κB expression in peripheral blood mononuclear cells, as well as pro-inflammatory cytokines. All statistical calculations were made using SPSS for Mac version 21.0. Results: Patients with reduced ejection fraction showed significantly lower hemoglobin levels (12.3 ± 1.4 vs. 13.6 ± 1.4 g/dl), serum iron (61.4 ± 18.3 vs. 93.7 ± 33.7 mcg/dl), transferrin iron binding capacity (20.7 ± 8.4 vs. 31.1 ± 15.6 %), and e-GFR values (78.1 ± 36.1 vs. 118.1 ± 33.9 ml/min/1.73 m2) in comparison to patients with preserved ejection fraction, while unsaturated iron binding capacity (272.6 ± 74.9 vs. 221.7 ± 61.4 mcg/dl), hepcidin (4.61 ± 0.89 vs. 3.28 ± 0.69 ng/ml), and creatinine (1.34 ± 0.55 vs. 1.03 ± 0.25 mg/dl) were significantly higher in the same group. When considering inflammatory parameters, patients with reduced ejection fraction showed significantly higher expression of both Toll-like receptors-2 (1.90 ± 0.97 vs. 1.25 ± 0.76 MFI) and Toll-like receptors-4 (4.54 ± 1.32 vs. 3.38 ± 1.62 MFI), respectively, as well as a significantly higher activity of NF-κB (2.67 ± 0.60 vs. 1.07 ± 0.30). Furthermore, pro-inflammatory cytokines, interleukin-1, and interleukin-6, was significantly higher in patients with reduced ejection fraction, while the protective cytokine interleukin-10 was significantly lower in the same group. Correlational analyses demonstrated a significant and inverse relationship between left ventricular function and inflammatory parameters in patients with reduced ejection fraction, as well as a direct correlation between ferritin and inflammatory parameters. Conclusions: Our data demonstrate a different immune-mediated inflammatory burden in heart failure patients with reduced or preserved ejection fraction, as well as significant differences in iron status. These data contribute to further elucidate pathophysiologic mechanisms leading to cardiac dysfunction
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