334 resultados para SUBSTITUTED 1,8-NAPHTHALIMIDE DERIVATIVES


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Purpose The purpose of this study was to examine the validity of current practice in smoking cessation for the general population i.e., a telephone counselling and nicotine replacement therapy (NRT) intervention and its applicability to people with chronic hepatitis-C. Methods A randomised controlled trial was conducted over twelve weeks. Following consent, ninety-two smokers (outpatients) with chronic hepatitis-C were recruited by the Nurse Practitioner hepatology, randomly assigned and stratified by number of cigarettes smoked (i.e., 15 and greater; <15) into the intervention group (telephone counselling and NRT) and control group (telephone counselling). Outcomes measured included socio-demographics, nicotine dependence, depression, anxiety and stress and quality of life (QOL). All statistical data were analysed using SPSS. Results After 12 weeks, the intervention group showed a sustained reduction of smoking i.e., 5.8(CI: 2.4,9.3) cigarettes less per day, whereas the control group showed 1.6(CI:-1.9,5.2) cigarette reduction. Although not statistically significantly different (F=2.9, p=0.090) the intervention group on average smoked 4.2 fewer cigarettes compared to the control group. After twelve weeks, seven patients in the intervention group and three patients in the control group reported quitting. Whilst not statistically significant (Fisher’s Exact, p=0.311) this was a clinically significant result. No differences were found for nicotine dependence or depression, anxiety and stress. The intervention group experienced no change in QOL (-0.1,CI:-0.9, 0.6), however, the environmental score for the control group decreased by 1.8(CI:1.0, 2.6,p= 0.001). This was statistically significant. Conclusion A telephone counselling and nicotine replacement therapy intervention from the nurse practitioner, hepatology reduced smoking in patients with chronic hepatitis-C. The intervention group showed a sustained reduction over the 12 weeks. A total of 10 patients quit smoking at the end of the study. QOL deteriorated in the environmental subscale for the control group. These results informed a nurse practitioner model of care for approaches to smoking cessation.

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Introduction Standing radiographs are the ‘gold standard’ for clinical assessment of adolescent idiopathic scoliosis (AIS), with the Cobb Angle used to measure the severity and progression of the scoliotic curve. Supine imaging modalities can provide valuable 3D information on scoliotic anatomy, however, due to changes in gravitational loading direction, the geometry of the spine alters between the supine and standing position which in turn affects the Cobb Angle measurement. Previous studies have consistently reported a 7-10° [1-3] Cobb Angle increase from supine to standing, however, none have reported the effect of endplate pre-selection and which (if any) curve parameters affect the supine to standing Cobb Angle difference. Methods Female AIS patients with right-sided thoracic major curves were included in the retrospective study. Clinically measured Cobb Angles from existing standing coronal radiographs and fulcrum bending radiographs [4] were compared to existing low-dose supine CT scans taken within 3 months of the reference radiograph. Reformatted coronal CT images were used to measure Cobb Angle variability with and without endplate pre-selection (end-plates selected on the radiographs used on the CT images). Inter and intra-observer measurement variability was assessed. Multi-linear regression was used to investigate whether there was a relationship between supine to standing Cobb Angle change and patient characteristics (SPSS, v.21, IBM, USA). Results Fifty-two patients were included, with mean age of 14.6 (SD 1.8) years; all curves were Lenke Type 1 with mean Cobb Angle on supine CT of 42° (SD 6.4°) and 52° (SD 6.7°) on standing radiographs. The mean fulcrum bending Cobb Angle for the group was 22.6° (SD 7.5°). The 10° increase from supine to standing is consistent with existing literature. Pre-selecting vertebral endplates was found to increase the Cobb Angle difference by a mean 2° (range 0-9°). Multi-linear regression revealed a statistically significant relationship between supine to standing Cobb Angle change with: fulcrum flexibility (p=0.001), age (p=0.027) and standing Cobb Angle (p<0.001). In patients with high fulcrum flexibility scores, the supine to standing Cobb Angle change was as great as 20°.The 95% confidence intervals for intra-observer and inter-observer measurement variability were 3.1° and 3.6°, respectively. Conclusion There is a statistically significant relationship between supine to standing Cobb Angle change and fulcrum flexibility. Therefore, this difference can be considered a measure of spinal flexibility. Pre-selecting vertebral endplates causes only minor changes.

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The aim of this work was to investigate changes in particle number concentration (PNC) within naturally ventilated primary school classrooms arising from local sources either within or adjacent to the classrooms. We quantify the rate at which ultrafine particles were emitted either from printing, grilling, heating or cleaning activities and the rate at which the particles were removed by both deposition and air exchange processes. At each of 25 schools in Brisbane, Australia, two weeks of measurements of PNC and CO2 were taken both outdoors and in the two classrooms. Bayesian regression modelling was employed in order to estimate the relevant rates and analyse the relationship between air exchange rate (AER), particle infiltration and the deposition rates of particle generated from indoor activities in the classrooms. During schooling hours, grilling events at the school tuckshop as well as heating and printing in the classrooms led to indoor PNCs being elevated by a factor of more than four, with emission rates of (2.51 ± 0.25) x 1011 p min-1, (8.99 ± 6.70) x 1011 p min-1 and (5.17 ± 2.00) x 1011 p min-1, respectively. During non-school hours, cleaning events elevated indoor PNC by a factor of above five, with an average emission rate of (2.09 ± 6.30) x 1011 p min-1. Particles were removed by both air exchange and deposition; chiefly by ventilation when AER > 0.7 h-1 and by deposition when AER < 0.7 h-1.

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An electricity demand reduction project based on comprehensive residential consumer engagement was established within an Australian community in 2008. By 2011, both the peak demand and grid supplied electricity consumption had decreased to below pre-intervention levels. This case study research explored the relationship developed between the utility, community and individual consumer from the residential customer perspective through qualitative research of 22 residential households. It is proposed that an energy utility can be highly successful at peak demand reduction by becoming a community member and a peer to residential consumers and developing the necessary trust, access, influence and partnership required to create the responsive environment to change. A peer-community approach could provide policymakers with a pathway for implementing pro-environmental behaviour for low carbon communities, as well as peak demand reduction, thereby addressing government emission targets while limiting the cost of living increases from infrastructure expenditure.

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Spreading cell fronts are essential features of development, repair and disease processes. Many mathematical models used to describe the motion of cell fronts, such as Fisher’s equation, invoke a mean–field assumption which implies that there is no spatial structure, such as cell clustering, present. Here, we examine the presence of spatial structure using a combination of in vitro circular barrier assays, discrete random walk simulations and pair correlation functions. In particular, we analyse discrete simulation data using pair correlation functions to show that spatial structure can form in a spreading population of cells either through sufficiently strong cell–to–cell adhesion or sufficiently rapid cell proliferation. We analyse images from a circular barrier assay describing the spreading of a population of MM127 melanoma cells using the same pair correlation functions. Our results indicate that the spreading melanoma cell populations remain very close to spatially uniform, suggesting that the strength of cell–to–cell adhesion and the rate of cell proliferation are both sufficiently small so as not to induce any spatial patterning in the spreading populations.

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Carbon-doped hydrogenated silicon oxide (SiOCH) low-k films have been prepared using 13.56 MHz discharge in trimethylsilane (3MS) - oxygen gas mixtures at 3, 4, and 5 Torr sustained with RF power densities 1.3 - 2.6 W/cm2. The atomic structure of the SiOCH films appears to be a mixture the amorphous SiO2-like and the partially polycrystalline SiC-like phases. Results of the infra-red spectroscopy reflect the increment in the volume fraction of the SiC-like phase from 0.22 - 0.28 to 0.36 - 0.39 as the RF power increment. Steady-state near-UV laser-excited (364 nm wavelength, 40±2 mW) photoluminescence (PL) has been studied at room temperatures in the visible (1.8 eV - 3.1 eV) subrange of photon spectrum. Two main bands of the PL signal (at the photon energies of 2.5 - 2.6 eV and 2.8 - 2.9 eV) are observed. Intensities of the both bands are changed monotonically with RF power, whereas the bandwidth of ∼0.1 eV remains almost invariable. It is likely that the above lines are dumped by the non-radiative recombination involving E1-like centres in the amorphous-nanocrystalline SiC-like phases. Such explanation of the PL intensity dependences on the RF power density is supported by results of experimental studies of defect states spectrum in bandgap of the SiOCH films.

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The aim of this paper is to determine the strain-rate-dependent mechanical behavior of living and fixed osteocytes and chondrocytes, in vitro. Firstly, Atomic Force Microscopy (AFM) was used to obtain the force-indentation curves of these single cells at four different strain-rates. These results were then employed in inverse finite element analysis (FEA) using Modified Standard neo-Hookean Solid (MSnHS) idealization of these cells to determine their mechanical properties. In addition, a FEA model with a newly developed spring element was employed to accurately simulate AFM evaluation in this study. We report that both cytoskeleton (CSK) and intracellular fluid govern the strain-rate-dependent mechanical property of living cells whereas intracellular fluid plays a predominant role on fixed cells’ behavior. In addition, through the comparisons, it can be concluded that osteocytes are stiffer than chondrocytes at all strain-rates tested indicating that the cells could be the biomarker of their tissue origin. Finally, we report that MSnHS is able to capture the strain-rate-dependent mechanical behavior of osteocyte and chondrocyte for both living and fixed cells. Therefore, we concluded that the MSnHS is a good model for exploration of mechanical deformation responses of single osteocytes and chondrocytes. This study could open a new avenue for analysis of mechanical behavior of osteocytes and chondrocytes as well as other similar types of cells.

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Optimisation of Organic Rankine Cycles (ORCs) for binary cycle applications could play a major role in determining the competitiveness of low to moderate renewable sources. An important aspect of the optimisation is to maximise the turbine output power for a given resource. This requires careful attention to the turbine design notably through numerical simulations. Challenges in the numerical modelling of radial-inflow turbines using high-density working fluids still need to be addressed in order to improve the turbine design and better optimise ORCs. This paper presents preliminary 3D numerical simulations of a radial-inflow turbine working with high-density fluids in realistic geothermal ORCs. Following extensive investigation of the operating conditions and thermodynamic cycle analysis, the refrigerant R143a is chosen as the high-density working fluid. The 1D design of the candidate radial-inflow turbine is presented in details. Furthermore, commercially-available software Ansys-CFX is used to perform the 3D CFD simulations for a number of operating conditions including off-design conditions. The real-gas properties are obtained using the Peng-Robinson equations of state. The preliminary design created using dedicated radial-inflow turbine software Concepts-Rital is discussed and the 3D CFD results are presented and compared against the meanline analysis.

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High voltage powerlines may give rise to corona breakdown, resulting in the release of large concentrations of charged ions into the surrounding environment. These ions quickly attach to aerosols and the resulting charged particles are carried by prevalent winds. This paper describes a study carried out at a site near an overhead double circuit ac transmission voltage powerline to investigate factors that control the rate at which charged particles are produced, and to determine the total particle number concentrations, total particle charge concentrations and vertical dc electric fields in the proximity of the line. Measured mean values of these three parameters at a perpendicular distance of 50m from the line were 1.8 x 103 particle cm-3, 518 ions cm3 and 520 V m-1 respectively. The net electric charge was positive and the electric field was directed downwards. These parameters were correlated with each other and monitored at four different distances from the line. Effects of meteorological parameters such as wind speed and wind direction were also investigated.

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Taking into consideration of growing energy needs and concern for environmental degradation, clean and inexhaustible energy source, such as solar energy, is receiving greater attention for various applications. The use of solar energy system reduces pollution, waste and has little or no harmful effects on the environment. It is appreciated that this source of energy can be complementary rather than being competitive to conventional energy sources. In order to collect and harness energy from the sun, a solar collector is essential. A solar collector is basically a heat exchanger that transforms solar radiant energy into heat or thermal energy. Improvement of performance is essential for commercial acceptance of their use in such applications. Many studies have been undertaken on the enhancement of thermal performance of solar collectors, using diverse materials of various shapes, dimensions and layouts. In the literature, various collector designs have been proposed and tested with the objective of meeting these requirements [1-8]. Omer et al. [1] found the efficiency of a solar collector of about 70% in a solar assisted heat pump system. Traditional solar collectors are single phase collectors, in which the working fluid is either air or water. Different modifications are suggested and applied to improve the heat transfer between the absorber and working fluid in a collector. These modifications include the use of absorber with fins attached [2,3], corrugated absorber [4,5], matrix type absorber [6], V-groove solar air collector [7]. Karim et al. [8] approached a review of design and construction of three types (flat, vee-grooved, and finned) of air collectors. Two-phase collectors, on the other hand, have significant potential for continuous operation round the clock, when used in conjunction with a compressor, as found in a solar assisted heat-pump cycle.

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Optimisation is a fundamental step in the turbine design process, especially in the development of non-classical designs of radial-inflow turbines working with high-density fluids in low-temperature Organic Rankine Cycles (ORCs). The present work discusses the simultaneous optimisation of the thermodynamic cycle and the one-dimensional design of radial-inflow turbines. In particular, the work describes the integration between a 1D meanline preliminary design code adapted to real gases and the performance estimation approach for radial-inflow turbines in an established ORC cycle analysis procedure. The optimisation approach is split in two distinct loops; the inner operates on the 1D design based on the parameters received from the outer loop, which optimises the thermodynamic cycle. The method uses parameters including brine flow rate, temperature and working fluid, shifting assumptions such as head and flow coefficients into the optimisation routine. The discussed design and optimisation method is then validated against published benchmark cases. Finally, using the same conditions, the coupled optimisation procedure is extended to the preliminary design of a radial-inflow turbine with R143a as working fluid in realistic geothermal conditions and compared against results from commercially-available software RITAL from Concepts-NREC.

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Time-resolved photoluminescence spectroscopy experiments of three poly(2,8-indenofluorene) derivatives bearing different pendant groups are presented. A comparison of the photophysical properties of dilute solutions and thin films provides information on the chemical purity of the materials. The photophysical properties of poly(2,8-indenofluorene)s are correlated with the morphological characteristics of their corresponding films. Wide-angle X-ray scattering experiments reveal the order in these materials at the molecular level. The spectroscopic results confirm the positive impact of a new synthetic approach on the spectral purity of the poly(indenofluorene)s. It is concluded that complete side-chain substitution of the bridgehead carbon atoms C-6 and C-12 in the indenofluorene unit, prior to indenofluorene ring formation, reduces the probability of keto formation. Due to the intrinsic chemical purity of the arylated derivative, identification of a long-delayed spectral feature, other than the known keto band, is possible in the case of thin films. Controlled doping experiments on the arylated derivative with trace amounts of an indenofluorene-monoketone provide quantitative information on the rates of two major photophysical processes, namely, singlet photoluminescence emission and singlet photoluminescence quenching. These results allow the determination of the minimum keto concentration that can affect the intrinsic photophysical properties of this polymer. The data suggest that photoluminescence quenching operates in the doped films according to the Stern-Volmer formalism.

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New push-pull copolymers based on thiophene (donor) and benzothiadiazole (acceptor) units, poly[4,7-bis(3-dodecylthiophene-2-yl) benzothiadiazole-co- thiophene] (PT3B1) and poly[4,7-bis(3-dodecylthiophene-2-yl) benzothiadiazole-co-benzothiadiazole] (PT2B2), are designed and synthesized via Stille and Suzuki coupling routes respectively. Gel permeation chromatography shows the number average molecular weights are 31100 and 8400 g mol-1 for the two polymers, respectively. Both polymers have shown absorption throughout a wide range of the UV-vis region, from 300 to 650 nm. A significant red shift of the absorption edge is observed in thin films compared to solution of the copolymers; the optical band gap is in the range of 1.7 to 1.8 eV. Cyclic voltammetry indicates reversible oxidation and reduction processes with HOMO energy levels calculated to be in the range of 5.2 to 5.4 eV. Upon testing both materials for organic field-effect transistors (OFETs), PT3B1 showed a hole mobility of 6.1 × 10-4 cm2 V-1 s -1, while PT2B2 did not show any field effect transport. Both copolymers displayed a photovoltaic response when combined with a methanofullerene as an electron acceptor. The best performance was achieved when the copolymer PT3B1 was blended with [70]PCBM in a 1:4 ratio, exhibiting a short-circuit current of 7.27 mA cm-2, an open circuit voltage of 0.85 V, and a fill factor of 41% yielding a power conversion efficiency of 2.54% under simulated air mass (AM) 1.5 global (1.5 G) illumination conditions (100 mW cm-2). Similar devices utilizing PT2B2 in place of PT3B1 demonstrated reduced performance with a short-circuit current of 4.8 mA cm -2, an open circuit voltage of 0.73 V, and a fill factor of 30% resulting in a power conversion efficiency of roughly 1.06%.

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This study investigates potential demand for infrastructure investment for alternative fuel vehicles by applying stated preference methods to a Japanese sample. The potential demand is estimated on the basis of how much people are willing to pay for alternative fuel vehicles under various refueling scenarios. Using the estimated parameters, the economic efficiency of establishing battery-exchange stations for electric vehicles is examined. The results indicate that infrastructural development of battery-exchange stations can be efficient when electric vehicle sales exceed 5.63% of all new vehicle sales. Further, we find a complementary relationship between the cruising ranges of alternative fuel vehicles and the infrastructure established.

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The paper analyses technical efficiency of the Japanese banks from 2000 to 2007. The estimation technique is based on the Russell directional distance function that takes into consideration not only desirable outputs but also an undesirable output that is represented by non-performing loans (NPLs). The results indicate that NPLs remain a significant burden as for banks' performance. We show that banks' inputs have to be utilised more efficiently, particularly labour and premises. We also argue that a further restructuring process is needed in the segment of Regional Banks. We conclude that the Japanese banking system is still far away from being fully consolidated and restructured.