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Studying tissue hemodynamics following breast compression has the potential to reveal new contrast mechanisms for evaluating breast cancer. However, how compression will be distributed and, consequently, how hemodynamics will be altered inside the compressed breast remain unclear. To explore the effect of compression, 12 healthy volunteers were studied by applying a step compression increase (4.5–53.4 N) using an optical imaging system capable of concurrently measuring pressure distribution and hemodynamic responses. Finite element analysis was used to predict the distribution of internal fluid pressure (IFP) in breast models. Comparisons between the measured pressure distribution and the reconstructed hemodynamic images for the healthy volunteers indicated significant (p < 0.05) negative correlations. The findings from a breast cancer patient showed that IFP distribution during compression strongly correlates with the observed differential hemodynamic images. We concluded that dynamic breast compression results in non-uniform internal pressure distribution throughout the breast that could potentially drive directed blood flow. The encouraging results obtained highlight the promise of developing dynamic optical imaging biomarkers for breast cancer by interpreting differential hemodynamic images of breast tissue during compression in the context of measured pressure distribution and predicted IFP.

•We studied the electronic structures of BeXP2 (X=Si and Ge) chalcopyrite.•Mechanical properties of both two compounds have been investigated.•The compounds are promising candidates for future optoelectronic applications.

AbstractDirect Geo-Referencing is a new technique in photogrammetry, especially in the aerial photogrammetry. Unlike the Aerial Triangulation “AT”, this method does not require Ground Control Points “GCPs”, to process aerial photographs into desired ground coordinates systems. Compared with the old method, this method has four main advantages: faster field work, faster data processing, simple workflow and less cost. Generally, direct geo-referencing using two systems, Global Navigational Satellite Systems “GNSS” and Inertial Navigational System “INS”. GNSS recording the camera coordinates “X, Y, Z”, and INS recording the camera orientation angles “w, φ, k” at the time of exposure. These parameters merged and are provided to each photograph in the processing stage.The current paper investigates the using GNSS system for providing the linear exterior orientation “EO” parameters “X, Y, Z” by two techniques, real time kinematic “RTK” and virtual reference system “VRS”. The accuracy of the applied method is tested on topographic survey project in Switzerland. The surveyed data of the specified project were collected by amateur digital camera Canon 18.2 MP, 182 captured images from approximately 85m flight height, 18 Ground Check Point “GCP” determined by static GNSS. Horizontal accuracy is 0.029m for VRS case, 0.034m for RTK case and vertical accuracy is 0.026m for VRS case, 0.029 for RTK case.

MP2 method and different functionals such as M06-HF, M06-2X, CAM-B3LYP, PBE0, B3LYP and M06L incorporating different XC amounts were used to calculate the static first hyperpolarizabilies β(0) of eight molecules which are derivatives of benzene, stilbene and diphenylacetylene. The values were then compared to the experimental ones. The M06-2X functional was then selected for further calculations. NBO calculations were also performed to define the intramolecular charge transfer in each molecule. TD-DFT calculations were performed taking into account the solvent effect using the IEF-PCM formalism. Some parameters characterizing the vertical transitions such as the wavelength of the maximum absorption λmaxwere compared to the experimental ones. Finally, solvation Gibbs free enthalpy ∆Gsolvvalues have also been examined in order to determine which the specific solvent for a given molecule is.

Continuous wave optical tomography is non-ionizing, uses endogenous contrast, and can be performed quickly and at low cost which makes it a suitable imaging modality for breast cancer screening. Using multiple wavelengths of light to illuminate the breast at various angles, three-dimensional images of the distribution of chromophores such as oxy- and deoxy-hemoglobin can help identify cancerous tissue. Dynamic optical imaging can provide additional insight into cancer characteristics such as angiogenesis and metabolism. Here we present the first clinical data acquired with our novel digital breast imaging system. This system is based upon a Digital Signal Processor (DSP) architecture that leverages the immediate digitization of acquired analog data to reduce noise and quickly process large amounts of data. Employing this new instrument we have investigated the dynamic changes due to a breath hold and its potential for use in breast cancer screening. Over the course of a breath hold, images have been collected simultaneously from both breasts at a rate of 1.7 frames per second with 32 sources and 64 detectors per breast and four wavelengths of light at 765, 805, 827, and 905nm. Initial results involving one healthy volunteer and one breast cancer patient support the potential use of dynamic imaging for breast cancer detection.

The lifetime of graphite anodes in sulphuric acid media can be increased by a factor of 3.2 by multiple impregnation with coal tar pitch. For single impregnation, linseed oil yielded the largest improvement. The results were interpreted on the premise that properties such as viscosity, melting point and coking value determine the effectiveness of the impregnant. The proper selection of the impregnant and procedure of impregnation is dependent on the electrolysis temperature.

Graphite electrodes were prepared by mixing calcined coke and coal tar pitch. They were pressed under 250 kg cm-2 and heat treated up to 2800° C. Rectangles measuring 70 mm x 40 mm x 8 mm were anodically polarized under galvanostatic and potentiostatic conditions. Electrolyses were conducted at 10–50 mA cm-2 for periods ranging from 10–120 hours in Na2SO4 solutions acidified with sulphuric acid to various pH values. The wear of graphite anodes increased with decreasing bath temperature, increasing acid concentration, decreasing pH of the electrolyte and increasing current density. A model is suggested which assumes that corrosion takes place via the formation of a lamellar crystal compound with the formula (C80O)(OH)3HSO4-·2H2SO4.

The lifetime of mechanical carbon sealing rings fitted into crude petroleum oil pumps can be increased by a factor of 43 by multiple impregnation with coal tar pitch. For single impregnation, epoxy resin yielded the largest improvement. The results were interpreted on the premise that properties such as viscosity, adhesion forces, and coking value determine the effectiveness of the impregnant. The proper selection of the impregnant and procedure of impregnation is dependent on the pumping pressure and oil properties.

Free powders as well as compacts of molybdenum and cobalt have been successfully recovered from spent hydrogenation and desulphurisation catalysts. A mixture of concentrated sulphuric and nitric acids (3: 1 by volume) achieved adequate levels of recovery of both metals, which increased with increase in acid concentration, time (up to 3 h), and temperature (100°C), and with decrease in particle diameter of the spent catalyst. The process flow sheet involved crushing, milling, particle sizing, acid leaching, and roasting of the obtained hydroxides in an atmospheric oxygen to obtain the respective oxides. These were reduced under a constant mass flowrate of hydrogen gas at 1100 and 900°C respectively. Parameters affecting the properties of the products and the recovery efficiency value, such as acid concentration, particle diameter of the solid catalyst, temperature, and time, have been investigated. The results obtained showed that the maximum recovery efficiency amounted to 96%. The recovered metal powders are technically pure, meeting the standard specifications. Compact shapes of molybdenum acquired density values which increased with an increase of the pressing load, whereby a density value of 2280 kg m−3is attained at ≥0 ·75 MPa. A model explaining the obtained results assumes that the molybdenum and cobalt in the spent catalyst are supported by the carrier. During operation, carbon particles are deposited and poison the catalyst. The weight ratio of carbon increases as the particle size of the catalyst decreases. Nitric acid helps dissolution of these metals to form complex sulphate salts. High oxide states of molybdenum and cobalt are formed by roasting in atmospheric oxygen. Reduction with hydrogen gas takes place in two steps, the overall activation energy of which amounts to 144·39 kJ mol−1for molybdenum and 143·4 kJ mol−1for cobalt. The metal powders have a rough surface with an irregular shape. Densification of these powders by pressing takes place as a result of random movement of the metal particles. Above a critical load, the minimum void volume is achieved at which the interparticle friction resists the applied load. A study has revealed that spent catalyst contains molybdenum and cobalt that are economically recoverable. Cost of recovery and the process of recovery is simple. PM/0709

The aim purpose of this study is to investigate the structural, elastic, magnetic, electronic properties and half-metallic stability under pressure of ScNiCrZ (Z=Al, Ga and In) quaternary Heusler alloys using full-potential linear muffin-tin orbital (FP-LMTO) method within the gradient generalized approximation (GGA) for exchange, and correlation potential. In order to evaluate the stability of our compounds, the formation energy, and elastic constants have been evaluated. The results showed that our compounds have ferromagnetic ground states and are energetically more stable in type-γconfiguration. True half-metallic ferromagnetic behavior with 100% spin polarization at Fermi level EFwith high Curie temperature Tc, and very interesting bandgap in the minority spin are obtained for the three alloys. The calculated total magnetic moment MTfor all three alloys is consistent with Slater−Pauling rule. The half-metallicity is maintained over a wide range of lattice constants making these alloys promising for spintronic, and magneto-electronics applications.

In this study, we carried out ab-initiocalculations of structural, electronic, optical and thermo-electric properties of CaTaO2N compound in Pnma orthorhombic structure, using the full-potential linearized augmented plane wave method (FP-LAPW), within the framework of density functional theory (DFT). The calculated structural parameters are found to be in good agreement with the experimental results. Moreover, we have studied the electronic band structure, total and partial density of states in order to explain the origin of band gaps and the nitrogen anion contribution in the valence and the conduction bands. The CaTaO2N band structure has shown a direct band gap in the direction Γ→Γ(with the value 2.32eV). The optical properties represented by the dielectric functions for CaTaO2N compound have revealed that the Pnma structure absorbs the light at a large window in the edge UV-Vis regions. In order to explain the thermo-electric properties, we have calculated Seebeck coefficient, electrical conductivity, thermal conductivity and the factor figure of merit in this temperature range 100–1000 K. The factor figure of mérit (ZT) of CaTaO2N takes a maximum value of 0.775 at T=1000K.

In this paper, we investigate the structural, electronic and magnetic properties of CoFeCrZ (Z=P, As,Sb) quaternary Heusler alloy, using the first-principles full potential linear muffin-tin orbital (FP-LMTO) method within the spin gradient generalized approximation (GGA) for the exchange and correlation potential. Our results demonstrate that in ferromagnetic phase, the all alloys CoFeCrZ are stable in type-1 configuration and are half-metallic ferromagnets (HMF) with gaps of 0.99eV, 0.57eV and 0.70Ev, respectively. The obtained negative formation energy shows that CoFeCrZ alloys have strong structural stability. The calculated total magnetic moment, MTfor all alloys exhibit Slater-Pauling rule, MT=(NV−24)μB. At zero pressure, the three alloys shown 100% spin-polarization at Fermi–level EFwith high Curie temperatures Tc. Our calculation indicate also that the half-metallicity and high magnetic moment of CoFeCrP, CoFeCrAs and CoFeCrSb are robust against the lattice compression (up to 7.80%, 5.40% and 11%, respectively). On the basis of these results, it is suggested that the CoFeCrZ Heusler could be suitable for spintronics devices applications.

A hydro-pyrometallurgical method was used to recover metal values from spent dry battery cells. Water-soluble ingredients were filtered, and solid residue was sorted by magnetic separation and water flotation. Parameters affecting the recovery efficiency were also studied. Results revealed that metallic parts, carbon rods, and paper were safely recovered; pure NH4Cl, MnO2, and ZnCl2salts were obtained. Maximum recovery efficiencies reached 93 percent for manganese and 99.5 percent for zinc and NH4.

Targeting the patient’s needs and preferences has become an important contributor for improving care delivery, enhancing patient satisfaction, and achieving better clinical outcomes. This study aimed to examine the impact of applying quality management practices on patient centeredness within the context of health care accreditation and to explore the differences in the views of various health care workers regarding the attributes affecting patient-centered care. Our study followed a cross-sectional survey design wherein 4 Jordanian public hospitals were investigated several months after accreditation was obtained. Total 829 clinical/nonclinical hospital staff members consented for study participation. This sample was divided into 3 main occupational categories to represent the administrators, nurses, as well as doctors and other health professionals. Using a structural equation modeling, our results indicated that the predictors of patient-centered care for both administrators and those providing clinical care were participation in the accreditation process, leadership commitment to quality improvement, and measurement of quality improvement outcomes. In particular, perceiving the importance of the hospital’s engagement in the accreditation process was shown to be relevant to the administrators (gamma = 0.96), nurses (gamma = 0.80), as well as to doctors and other health professionals (gamma = 0.71). However, the administrator staff (gamma = 0.31) was less likely to perceive the influence of measuring the quality improvement outcomes on the delivery of patient-centered care than nurses (gamma = 0.59) as well as doctors and other health care providers (gamma = 0.55). From the nurses’ perspectives only, patient centeredness was found to be driven by building an institutional framework that supports quality assurance in hospital settings (gamma = 0.36). In conclusion, accreditation is a leading factor for delivering patient-centered care and should be on a hospital’s agenda as a strategy for continuous quality improvement.

No abstract.