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Hydrogels based on polyacrylamide (PAM) and sodium alginate (AG) were fabricated via gamma irradiation. The structure–property behavior of PAM/AG hydrogels was characterized by FTIR spectroscopy, and water absorption measurements. The PAM/AG hydrogels were applied as drug delivery taking chlortetracycline and ketoprofen as drug models. In addition, the water diffusion and drug release kinetics were investigated by applying the Fick's law, in which the mechanism for water diffusion and drug release was suggested. The results clarified the pH-sensitivity of the PAM/AG blend hydrogels towards the drug-release medium in the case of both drugs. [ABSTRACT FROM AUTHOR]

The main objective of this work is to impart UV protection properties to cotton and cotton/polyester fabrics and enhance the original chemical and physical properties. In this procedure, the fabrics were coated with nanocomposites based on poly(vinyl alcohol)/plasticized starch (PVA/PLST (80/20%)/Zn NPs. The coated fabrics were then exposed to gamma radiation to induce cross-linked layer structure covering the fibers of the fabrics. The formation of Zn NPs was confirmed by UV/Vis and XRD analysis. In addition, the coated fabrics were characterized by the measurements of water absorption, crease recovery, thermal stability, surface morphology and tensile mechanical measurements. The UV protection of the coated fabrics was determined. The results indicated that the coated fabrics showed highly reducing UV-A, UV-B and ultraviolet protection factor (UPF), particularly with increasing irradiation dose, regardless of fabric kind. It was found that cotton and cotton/PET fabrics treated with PVA/PLST/Zn NPs nanocomposites irradiated to a dose of 30 kGy displayed UPF excellent rating values of 44.31 and 58.23, respectively. [ABSTRACT FROM AUTHOR]

The nonlinear absorption (NLA) properties of ITO thin films were performed by utilizing femtosecond (100 fs), a high-repetition rate (80 MHz), and near-infrared (NIR) (750–820 nm) laser pulses. A radio frequency (RF) magnetron sputtering system was used to prepare ITO thin films of two different thicknesses. A scanning electron microscope was used to determine the film thickness and a UV–Visible spectrophotometer was used to observe the linear optical properties of the thin films. The open aperture Z-scan technique's nonlinear absorption studies of ITO thin films exhibited a reverse saturable absorption. The NLA properties of the ITO films varied depending on ITO thickness, incident laser power, and excitation wavelength, attributed to the increasing localized defect states in the band gap. The results showed that increasing the excitation wavelength from 750 to 820 nm reduces the nonlinear absorption coefficient of the ITO thin films from 15.88 × 10−7 to 9.43 × 10−7 cm/W and from 6.72 × 10−7 to 5.15 × 10−7 cm/W at ITO thicknesses of 280 and 170 nm, respectively. In contrast to the film thickness, the nonlinear absorption coefficient was inversely proportional to the excitation laser wavelength. Additionally, the optical limiting of ITO thin films was investigated, and it was found that there is a clear correlation between optical limiting and thin film thickness. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) and spermine (SPM) elicit particular responses in response to various environmental stressors. However, there is little known about the underlying mechanism of their combination treatments' mediating effect on salt stress tolerance. In this investigation, the potential impact of 100 mg L−1 SA and/or 30 mg L−1 SPM in avoiding salt damage at saline environments of 6.0 and 12.0 dS m–1 in wheat was examined. Results showed that by increasing mineral acquisition, chlorophyll a and b contents, antioxidant enzymes activity, osmolytes accumulation, leaf water content, grains carbohydrate and protein content as well as reducing Na+ accumulation, membrane electrolyte leakage, malondialdehyde and hydrogen peroxide contents, exogenously applied SA and/or SPM significantly reduced the detrimental impacts of soil salinization and increased wheat growth and productivity. The best outcomes came from combining the SA and SPM treatments. Overall, this combined treatment enhanced mineral homeostasis, osmolytes accumulation, and antioxidant response, pointing to a potential role for it in minimizing the negative consequences of salt stress. Therefore, combining SA and SPM in a sustainable agricultural system can be viewed as a successful technique for reducing salt damage. [ABSTRACT FROM AUTHOR]

Due to the frequent urban air pollution episodes over Kuwait recently, decision-makers and government agencies are struggling for sustainable strategies to optimize urban land use and land cover change (LUCC) and improve air quality. This article is targeting to identify the underlying relationships between dust concentration variations and LUCC, using the numerical modelling approach. The RegCM4 and WRF-CHEM models were employed to explore the impacts of land use change over Kuwait to be Evergreen Broad-leaf instead of Desert. Results reveal that both models performed good estimate in two severe dust storm cases, as they detected these cases with reasonable concentrations compared to the reanalysis data with positive correlation, and the overall mean dust concentrations in the target area declined by approximately 6–50% using RegCM4 and 25% with WRF in both dust episodes. Besides, the LUCC affected the wind directions around the area of LUCC; however, it had no impact on the wind's strength. These results suggested that LUCC caused by an increase in long trees might be an important factor for the PM10 concentration reduction in Kuwait and would need to be investigated over a longer period. [ABSTRACT FROM AUTHOR]

Herein, I describe a study on the impact of substrate temperature on the structural, optical and photo-catalytic activity of sputtered Cu-doped ZnO thin films. Cu-doped ZnO nanocrystalline thin films of 10 wt.% Cu were first prepared at different substrate temperatures by radio frequency magnetron sputtering. Energy-dispersive X-ray spectroscopy was used to verify the percentage of Cu-doping. Both the structural and optical changes for the deposited thin films were measured by different characterization techniques. The nature of the deposited films was measured by X-ray diffraction analysis (XRD) that showed four characteristic peaks (002), (103), (100), and (111) related to ZnO. The intensity of the XRD peaks was affected by Cu-doping and increasing the substrate temperatures. The surface morphology and roughness for the prepared thin films were measured by atomic force microscopy. The calculated optical band gap of the prepared thin films deceased from 3.16 eV for the pure ZnO to 2.74 eV, 2.71 eV, 2.69 eV and 2.66 eV for the 10 wt.% Cu-doped ZnO thin film deposited at room temperature, 100°C, 200°C, and 300°C, respectively. The photoluminescence (PL) spectra for the prepared thin films were recorded to examine the impact of Cu-doping and the effect of increasing the substrate temperatures. As a photo-catalyst, the deposited thin films demonstrated high efficiency and stability concerning the degradation of methylene blue organic dye under a 500 W visible lamp and reusability for photo-catalytic experiments without much loss. [ABSTRACT FROM AUTHOR]

The electrical contact nature between metal and semiconductor plays a key role in the devices operating and performance. An investigation of the contact ohmicity of different metals with p-NiO and n-ZnO semiconducting material is addressed in the present work. The investigated metals are the commonly used ones: Au, Cu, Mo, Ti, Ag, and indium tin oxide (ITO). All the studied metals lead to an ohmic contact with NiO and ZnO semiconductors expected in the case of ITO on NiO where the contact was rectifying. The formation of ohmic contact is explained in terms of the difference between the metal work function and the semiconductors affinity in one hand and on the other hand, in terms of highly doped interface formation due to the oxygen vacancies appearance, reducing then the depletion layer width which favors the carrier transport through tunneling effect. High sheet resistance is measured when using Ag metal as a contact on both ZnO and NiO, due to the diffusion of the latter in the film bulk and to the formation of Ag cluster. Mo, as well, leads to higher sheet resistance when used on NiO due to the metal diffusion. However, due to the conduction band gap offset at the interface ITO/NiO and ITO /ZnO, ITO leads to a Schottky contact with NiO and ohmic one with ZnO. [ABSTRACT FROM AUTHOR]

Copper oxide thin films have prepared by sputtering technique. Silicon intercalated copper oxide thin films as a dopant with a ratio ranged from 2.1 to 6.2 at%. The thickness of the prepared films decreased as Si dopant increase from 153 nm for the base CuO films to 54 nm for the 6.2 at% Si containing samples. Copper atoms are presented in divalent states, whereas silicon dopant existed as a major Si–O and minor metallic Si states. X-ray photoelectron spectroscopy (XPS) proved the chemical state of CuO, while the X-ray diffraction (XRD) approved the monoclinic crystal structure. The average crystallite size values decreased as the Si content increase from 164 to 124 Å. The surface morphology and roughness were examined by Atomic Force Microscopy (AFM). The existence of Si content in CuO lattice improved the morphology by reducing the grain size and surface roughness. The optical properties of studied films showed the dependence of optical band gap and static refractive index on the Si content. With the increase in Si content, the optical transition decreased from 2.18 to 1.88 eV. Moreover, the optical dispersion parameters were determined and discussed in terms of Wemple-DiDomenico model. The films are suggested to use as transparent semiconducting materials. [ABSTRACT FROM AUTHOR]

Zinc oxide nanorods have been prepared, to our knowledge, for the first time using the green chemistry route. The used growth solution was a mixture of Artemisia flowers extract zinc precursor salt. Nanorods have been grown on glass substrate preliminary coated with ZnO thin film prepared by sputtering, used as a seed layer. The synthesized nanostructures have been characterized by means of X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscope (SEM). The XRD analysis reveals that the nanorods are formed with hexagonal wurtzite structure with (002) preferential orientation. An interesting feature was observed is that the nanorods adopt the seed layer crystallographic orientation. [ABSTRACT FROM AUTHOR]

Nanocrystalline nickel oxide thin films were prepared by combined techniques of direct current sputtering (DC sputtering) and microwave plasma chemical vapor deposition to perform high-quality films. The prepared films were subjected to three different microwave powers at 400, 800, and 1200 W. The structural and morphological properties of the prepared films were investigated by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). The prepared films have a trigonal structure. The crystallite size was calculated from Scherer's formula and uniform dimensional model (UDM). The calculated size increased from 213 to 241 Å as the microwave power increases from 400 to 1200 W, respectively. The lattice strain was also calculated from UDM model, and it had a lower value of 1.8 × 10–3 at 800 W. The optical properties such as transmittance, reflectance, absorption coefficient, extinction coefficient, and the dispersion were investigated. The optical transition of such films was direct transition, and the optical band gap values were observed to decrease from 3.950 to 3.367 eV as the microwave power increase from 400 to 1200 W, respectively. The refractive index and the dispersion energy parameters were studied in detail, and the static and lattice dielectric constant were deduced. [ABSTRACT FROM AUTHOR]

Seasonal abundance of the two spotted spider mite, Tetranychus urticae (Koch) (Acari) infesting cucumber plants in Upper Egypt was studied during three seasons of 2014, 2015 and 2016 in Assiut Governorate. The obtained results showed that the spider mite, T. urtica population during spring plantations fluctuated in relatively high densities during whole season with a peak during the middle of May when the plant age was 43 day-old and the presence of an average level of temperature and relative humidity. In addition, the data indicated that the number of predators was not significantly correlated with pest populations during the spring plantations of 2015 and 2016 seasons, probably because of the lowest numbers of predators recorded in the studied area. The present study showed that the cucumber plants severely affected by the two spotted spider mite, T. urticae. In addition to the scarce numbers of predators recorded during spring and/or summer plantations. [ABSTRACT FROM AUTHOR]

This is a multidimensional review of mangrove fungi occurring as saprobes, pathogens and endophytes of a wide range of host substrates and those isolated from the water columns and sediments in mangroves. Eight-hundred and fifty taxa including 658 that are supported by both morphology and molecular data and 192 with only morphological data are listed. These constitute Ascomycota, the dominant group with 773 species, and 58 Basidiomycota, one Blastocladiomycota, five Chytridiomycota, and 13 Mucoromycota. This study also includes data on mangrove yeasts 103 Ascomycota, 39 Basidiomycota and 193 taxa isolated from sediments. Endophytes isolated from submerged parts of mangrove plants total 38. The most specious orders of mangrove fungi are Pleosporales 133, Saccharomycetales 102, Microascales 101, Eurotiales 87, Hypocreales 60 and Xylariales 54. Speciose genera include Candida 39, Aspergillus 53, Penicillium 17 and Corollospora 16. The highest number of mangrove fungi have been recorded from the Pacific Ocean 553, which is the largest ocean, followed by Indian 408 and Atlantic Oceans 259. Geographical distribution of mangrove fungi varied from ocean to ocean with only 109 taxa common to the Atlantic, Indian and Pacific Oceans. Of the various countries reported for mangrove fungi, India accommodates the highest number (339) followed by Thailand 303, Malaysia 171, Florida Everglades, USA 134 and Brunei 134. A total of 60 different mangrove plants and their associates have been surveyed for mangrove fungi. These results are discussed and compared with previous studies. [ABSTRACT FROM AUTHOR]

Copper oxide–zinc oxide (CuO–ZnO) thin films were prepared by a sputtering technique to examine the creation of a CuZnO thin-film nanocomposite. The base film was a zinc oxide layer. A copper oxide layer was deposited on glass coated with ZnO for different deposition times. The structure was examined by x-ray diffraction analysis. Plane (002) was detected for ZnO phase, while planes (111) and 1 ¯ 11 were detected for CuO phase. The crystallite size was calculated for both ZnO and CuO. The crystallite size of CuO phases increased with increasing deposition time, whereas the size of crystals of ZnO phase decreased. The film morphology and roughness were evaluated by scanning electron microscopy. Agglomeration of fine particles was observed. The film roughness decreased from 0.0685 nm for base ZnO films to 0.0357 nm for 800 s CuO–ZnO films. Elemental analysis of the film components was carried out by energy-dispersive x-ray spectroscopy. The ratio of O atoms remained constant at 50 at.%, while the Zn content decreased from 50% for the base sample to 27.66% for the 800 s CuO–ZnO sample. Optical properties, such as the optical absorption spectra, optical transition, and refractive index of the prepared films, were investigated. The optical transition was affected by the CuO layer and the film thickness. The optical bandgap decreased from 3.258 eV for ZnO films with thickness of 107 nm to 3.162 eV for 800 s CuO–ZnO films with thickness of 163 nm. Nonlinear optical behavior was deduced from the optical parameters, and was enhanced by the presence of CuO layers, increasing from 4.151 × 10−11 esu for the ZnO sample to 4.434 × 10−11 esu for the 800 s CuO–ZnO sample. The photoluminescence spectra of the films were investigated and interpreted. [ABSTRACT FROM AUTHOR]

This article is part of the Topical Collection on Infection and Inflammation Introduction The COVID-19 pandemic is in transition. Nuclear medicine patients Patients, being encouraged to follow proper hygiene procedures, are something that remains relevant during the transition phase and also in a post-COVID-19 world. Nuclear medicine imaging Currently, most nuclear medicine departments are reducing patient numbers by cutting down on the appointments given for routine, elective studies, and focusing on more urgent cases. [Extracted from the article]

In December 2019, a new type of coronavirus 2019-nCoV/SARS-CoV-2, causing COVID-19 disease, was extracted and identified from the lower respiratory tract samples of several patients in Wuhan, China [[3]]. The total number of confirmed cases, deaths associated with COVID-19, and affected countries and territories continues to grow; detailed statistics can be found at the WHO-Coronavirus disease (COVID-19) Pandemic site [[5]] or the John Hopkins Coronavirus Resource Centre. All staff members should receive specific training in identifying COVID-19 symptoms, hygiene procedures, handling COVID-19 patients, disinfection procedures, and use of personal protective equipment (PPE), among others [[10]]. Teleconsulting with patients prior to scheduling and the day before attending the nuclear medicine center must be established, in order to identify patients who may have COVID-19 symptoms. [Extracted from the article]

The study presents the deposition of nanostructured indium tin oxide thin films with thicknesses of 10, 30 and 50 nm on the polylactic acid (PLA) substrate by sputtering at 30°C . The absence of ITO peaks on the X-ray diffraction patterns confirms the amorphous state of ITO films and the X-ray photoelectron spectroscopy spectrum validates the deposition of ITO films on the PLA substrate. The results of atomic force microscopy of films exhibit variation in the average roughness of 0.3–1.5 nm when the thickness is increased. It was examined that optical transmission is dependent on the thickness of films which varies from 78 to 87% in the visible spectrum of 400–700 nm and the energy band gap varies from 3.95 to 4.02 eV. The films exhibit the low sheet resistance which is due to the formation of oxygen vacancies and dangling bonds. An increase in transmittance enhances the FOM of the ITO films on the PLA substrate. [ABSTRACT FROM AUTHOR]

Two 12-year simulations were conducted with the RegCM4 model to study how different hydrology schemes can affect the terrestrial hydrology cycle, the surface energy balance, and the regional climate of Africa and in particular tropical Africa. One simulation used the default TOP hydrology scheme in the CLM4.5 land surface model; the other used the variable infiltration capacity (VIC) hydrology model coupled to CLM4.5. The results show that the VIC scheme has a lower soil infiltration rate and hence lower surface soil moisture (10 cm in this study) relative to the default TOP scheme. This leads to a different partitioning of terms in the surface energy balance, with low evapotranspiration and high sensible heat flux, resulting in a net warming effect. The VIC simulation also has low relative humidity due to the low evapotranspiration rate. The low infiltration rate of the VIC hydrology also results in accumulation of moisture on the soil surface. In addition, the VIC scheme generates more precipitation, especially in the summer (JJA) season. Thus, the hydrology parameterization can affect not just the terrestrial hydrology cycle but also energy balance partitioning and hence the surface climate. Moreover, the VIC simulation has smaller biases in the surface energy flux and other surface climate variables in comparison with the default CLM4.5 run. We conclude that the VIC land surface hydrology scheme succeeds in controlling the infiltration rate, the surface soil moisture, and hence total evapotranspiration, which improves the surface energy balance and hence produces a better surface climate. Thus, we recommend the VIC hydrology scheme for future climate studies over Africa. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) belongs to carbon family with honeycomb structure having hydroxide, carbonyl, and carboxylic moieties at its basal plane. These functionalities are decreased in reduced graphene oxide (rGO), and this boosts the intrinsic properties of GO. Herein, in this work, the effect on physical and chemical properties of GO and rGO in combination with copper-doped zinc oxide (Cu-ZnO) thin films, prepared via DC/RF sputtering, was investigated for the very first time. The deposition of Cu-ZnO over rGO (Cu-ZnO@rGO) showed remarkably superior properties and presented an extension in d-spacing without preferred plane orientation of Cu-ZnO plane, and this was found to be due to its hydrophobic nature. The decrease in band gap of composite thin films was due to the surface electric charge conducted by GO or rGO. The enhanced dielectric constant is attributed due to increase in electron-hole pairs owing to the increase in sp2 hybridization. However, sp2 network was also found to be responsible to provide the conductivity path way which increases the dielectric loss in Cu-ZnO@rGO thin films as compared to that in Cu-ZnO@GO; this might be due to aggregation of Cu-ZnO nanoparticles over the rGO films in comparison with GO as evident from the morphological analysis by AFM. The change in surface chemistry was ascribed with the ratio of COOH, C=O, C-OH and C-C bonding in the Cu-ZnO@GO and Cu-ZnO@rGO thin films as unveiled in their XPS analysis. The developed thin films exhibited enhanced antimicrobial activity against E. coli and E. faecalis which might be due to the synergistic effects of Cu-ZnO with GO or rGO. [ABSTRACT FROM AUTHOR]

Pure and cobalt (Co) doped CuO thin films have been deposited by DC and AC reactive magnetron sputtering technique. The doping ratio has been controlled by the RF power of the AC sputtering unit. The sputtering power ranges from 0 to 50 W. The crystal structure of the films has been identified by X-ray diffraction. One of the peaks has been shifted toward the high diffraction angle. Energy dispersive analysis shows cationic deficiency of the pure and doped samples. Morphology of the films has been investigated by atomic force microscopy. Film roughness decrease with the increase of sputtering power. Spectrophotometry studies reveal that films darken with the increase of sputtering power. The current-voltage curves show Ohmic contacts and an enhancement in the conductivity with the increase of Co concentrations. Photoresponse measurements have shown that the film doped at 50 W is the best photodetector sensor. [ABSTRACT FROM AUTHOR]

Despite the recent advancement in graphene oxide (GO) as a host material in energy and environmental sectors, its composite thin films with metal oxides such as nickel oxide (NiO) and its optical, structural, chemical state, and photocatalytic activities have been poorly explored. Herein, we have reported the GO/NiO thin films preparation by a combination of chemical and physical deposition techniques (i.e. spin coating followed by DC/RF sputtering). The as-prepared composites thin films were characterised using Raman spectroscopy, X-ray diffraction/photoelectron spectroscopy scanning electron microscopy, and atomic force microscopy. The surface topography confirmed the uniform deposition of NiO over thin films of GO. The XPS results showed the formation of NiC along with the partial reduction in GO into graphene with their existing four constituents, i.e. NiO, NiC, GO, in the thin film composites. The classical plasmon, Wemple and Didomenico model, was first time applied for GO/NiO to compute energy loss functions, and dispersion energy parameters. The theoretical calculated values for the deposited GO/NiO thin films were found to be in very close agreement to the standard classical plasmon values. The change in spin orbital movement of Ni is considered due to the interaction between its nanoparticles and basal planes of GO. Thin films applied for the photodegradation of recalcitrant organic pollutant 2-chlorophenol (2-CP) revealed the dependence of photocatalytic efficiency on particle size and also on the interaction of GO with NiO rather than the ratio of NiO and GO in the films. [ABSTRACT FROM AUTHOR]

In this work, p-NiO/n-ZnO heterostructures were successfully prepared at room temperature using RF sputtering technique. The influence of ZnO layer thickness on the performance of the heterojunction was investigated. The deposited ZnO layers have a hexagonal Wurtzite structure with preferable growth orientations along (002) and (103) for thinner films. Increasing the thickness results in more crystallographic orientation randomness. The current-voltage measurements of the realized heterojunctions showed a clear rectifying behavior. The measured ideality factor varies from 2.5 to 1.6 according to the thickness of ZnO layer. The series resistance of the device is enlarged with increasing ZnO thickness. The deduced parameters from the I-V characteristics suggest that 200 nm is the optimal thickness of the ZnO layer according to our experimental conditions. We attribute the relatively better performance of this thickness to achieving reasonable compensation between serial resistance and ideality factor. The best heterojunction was tested and successfully used as a UV detector. [ABSTRACT FROM AUTHOR]

Zinc aluminate (ZnAl2O4) thin films have been deposited through direct current/radio frequency (DC/RF) magnetron sputtering by varying the applied power of an Aluminum (Al) target. The X-ray diffraction (XRD) pattern showed the formation of monophase ZnAl2O4 with spinel structure. Moreover, structural analysis like grain size, dislocation density, and lattice strain was calculated through the XRD obtained data. The surface morphological analysis through field emission scanning electron microscopy (FESEM) confirmed the formation of nano-size spinel ZnAl2O4. The transmittance of the ZnAl2O4 thin film was found to be dependent on the aluminum (Al) target power. An inverse relation was noticed between the transmittance and the Al-power. The optical band gap dependent refractive index, high-frequency dielectric, and static dielectric constant were calculated.Scheme of experimental work [ABSTRACT FROM AUTHOR]

ZnO thin films containing different ratios of Ti metal were prepared by the DC/RF sputtering technique. XPS analysis showed the presence of Ti content in the range from 0.9 to 1.5 at.%, and Ti was existed as Ti4+ states. Zincite phase has been detected by XRD technique through all samples and the crystallite size, the strain, and the dislocation density were estimated. Surface morphology and roughness were examined by atomic force microscopy. Optical absorbance and optical band gap were measured and determined. The optical band gap is proposed to be direct and varied from 3.25 to 3.282 eV as the Ti content increase. Photoluminescence properties show a highly intense peak at 412 nm related to the transition from shallow donor level to valence band comes from the interface traps through the grain boundaries. [ABSTRACT FROM AUTHOR]

Copyright of Der Kardiologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We studied the influence of balancing internal combustion engines on the performance of hydrodynamic plain bearings. A non-linear approach makes it possible to calculate the forces of pressure generated by the lubricant film. This approach is coupled with a dynamic calculation, which determines the inertia forces of the rod. The counterweight to balance the engine is applied to the heads of rods and not to the crankshaft. We chose three models of connecting rod (rod of an engine in series, rod with partial and rod with complete counterweight). To determine the lubricant pressure field in the bearing, the modified Reynolds equation was solved using the finite difference method, taking into account the boundary conditions of Reynolds. Since the bearing is subjected to a variable load, the mobility method was used to facilitate the resolution of the Reynolds equation. The proposed numerical simulation allowed us to analyze the influence of counterweight applied to the connecting rod head on the variation of the lubricant pressure field, the minimum film thickness, the axial flow and the friction torque in the big end bearing during the operating cycle. [ABSTRACT FROM AUTHOR]

Copyright of Der Kardiologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present a generalized shear deformation theory in combination with isogeometric (IGA) approach for nonlinear transient analysis of smart piezoelectric functionally graded material (FGM) plates. The nonlinear transient formulation for plates is formed in the total Lagrange approach based on the von Kármán strains, which includes thermo-piezoelectric effects, and solved by Newmark time integration scheme. The electric potential through the thickness of each piezoelectric layer is assumed to be linear. The material properties vary through the thickness of FGM according to the rule of mixture and the Mori-Tanaka schemes. Various numerical examples are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Pure and Si-doped ZnO (SZO) thin films at different concentration of Si (1.9 and 2.4 wt%) were deposited on highly cleaned glass substrate by radio frequency (DC/RF) magnetron sputtering. The morphological and structural investigations have been performed by atomic force electron microscope (AFM) and X-ray diffraction (XRD). The X-ray photoelectron spectroscopy was employed to study the composition and the change in the chemical state of Si-doped ZnO thin films. The optical observations like transmittance, energy band gap, extinction coefficient, refractive index, dielectric loss of pure and Si-doped ZnO thin films have been calculated. The linear optical susceptibility, nonlinear refractive index, and nonlinear optical susceptibility were also studied by the spectroscopic approach rather than conventional Z-scan method. The energy gap of Si-doped ZnO thin films was found to increase as compared to pure ZnO thin films. The crystallinity of the ZnO thin films was effected by the Si doping. The O1s spectra in pure and Si-doped ZnO revealed the bound between O and Zn ions and reduction in the surface oxygen with the Si doping. The chemical state analysis of Si 2p showed the conversation of Si to SiO and SiO. The increase in the first-order linear optical susceptibility χ and third-order nonlinear optical susceptibility χ was observed with the Si doping. The nonlinear studies gave some details about the applications of metal oxides in nonlinear optical devices. In short, this study showed that Si doping through sputtering has effected on the structural, surface and optical properties of ZnO thin films which could be quite useful for advanced applications such as metal-oxide-based optical devices. [ABSTRACT FROM AUTHOR]

This paper presents a generalized layerwise higher-order shear deformation theory for laminated composite and sandwich plates. We exploit a higher-order shear deformation theory in each layer such that the continuity of the displacement and transverse shear stresses at the layer interfaces is ensured. Thanks for enforcing the continuity of the displacement and transverse shear stresses at an inner-laminar layer, the minimum number of variables is retained from the present theory in comparison with other layerwise theories. The method requires only five variables, the same as what obtained from the first- and higher-order shear deformation theories. In comparison with the shear deformation theories based on the equivalent single layer, the present theory is capable of producing a higher accuracy for inner-laminar layer shear stresses. The free boundary conditions of transverse shear stresses at the top and bottom surfaces of the plate are fulfilled without any shear correction factors. The discrete system equations are derived from the Galerkin weak form, and the solution is obtained by isogeometric analysis (IGA). The discrete form requires the C continuity of the transverse displacement, and hence NURBS basis functions in IGA naturally ensure this condition. The laminated composite and sandwich plates with various geometries, aspect ratios, stiffness ratios and boundary conditions are studied. The obtained results are compared with the 3D elasticity solution, the analytical as well as numerical solutions based on various plate theories. [ABSTRACT FROM AUTHOR]

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In this study, the climatology of Saharan cyclones is presented in order to understand the Saharan climate, its variability and its changes. This climatology includes an analysis of seasonal and interannual variations, the identification and classification of cyclone tracks, and a presentation of their chief characteristics. The data used are drawn from the 1980-2009, 2.5° × 2.5°, NCEP/NCAR reanalysis (NNRP I) dataset. It is found that cyclone numbers increase in September-October-November (SON) at 4.9 cyclones per decade, while they decrease in June-July-August at 12.3 cyclones per decade. The identification algorithm constructed 562 tracks, which are categorized into 12 distinct clusters. Around 75 % of the Saharan cyclones originate south of the Atlas Mountains. The percentage of tracks that move over the Sahara is around 48 %. The eastern Mediterranean receives 27 % of the Saharan tracks, while the western basin receives only 17 and 8 % of all the Saharan cyclones decay over the Arabian Peninsula. The maximum cyclonic activity occurs in April. There is a general decrease in the number of tracks in all categories between 1993 and 2009, compared with the period between 1980 and 1992. About 72 % of the Saharan cyclones do not live more than 3 days, and about 80 % of the cyclones in the tracks never reach central pressures 1,000 hPa during their lifetimes. The maximum deepening in the tracks occurs over the western Mediterranean and over northern Algeria. [ABSTRACT FROM AUTHOR]

Objective: This phase II study aimed at investigating the correlation between O-methylguanine-DNA methyltransferase (MGMT) promoter methylation and protein expression, together with Ki-67 labeling index (LI), to response, time to progression (TTP), and overall survival (OS) in newly diagnosed glioblastoma multiforme (GBM) patients treated with temozolomide (TMZ) concomitant with and adjuvant to radiotherapy (RT). Methods: From June 2005 to August 2008, 34 adult patients (18-65 years), PS ≥70, with newly diagnosed GBM received TMZ 75 mg/m plus RT up to 60 Gy, followed by TMZ 175 mg/m 5 days every 4 weeks for 12 doses. MGMT Methylation-specific PCR assay, MGMT protein expression, and Ki-67 expression using immunohistochemistry (IHC) were performed on the tissue blocks. The patients were followed by MRI while MR spectroscopy (MRS) was performed for the stable cases or to confirm progression and accordingly Bevacizumab 10 mg/kg every 2 weeks was added to 7 patients till further progression was proved. Results: 31 cases were evaluable, 12 (38.7%) had unmethylated MGMT, while 19 (61.3%) were methylated. Seventeen cases (55%) were MGMT immunonegative while 14 cases (45%) were immunopositive. The cut off value of Ki-67 LI in relation to survival was 17%, where 15 were < 17% (48.4%), and 16 were ≥ 17% (51.6%). Response evaluation started after the second dose of the adjuvant TMZ and was repeated every 2 months. The overall disease control rate (ODC) was 74.2%, where 2 patients had complete response (CR), 14 had partial response (PR), and 7 had stable disease (SD), while 8 (25.8%) had progressive disease (PD). The ODC was significantly higher among methylated patients and in those with Ki-67 < 17% ( P = 0.0003). The median overall TTP was 12 months and the median OS was 20 months for all the patients including those who received Bevacizumab for some stable cases or as a salvage treatment in patients with good PS, the MGMT-methylated patients had a higher median TTP of 13 months (range 8 to 18 months, 95% CI of 9.36 to 12.9), and OS of 24 months (range 12 to 31 months, 95% CI of 16.1 to 21.32), while the unmethylated patients had a median TTP of 6.5 months and a median OS of 12 months, such correlations were highly significant ( P = 0.0001). MGMT immunoexpression failed to show significant correlation with MGMT promotor methylation or the outcome of the patients. Patients with Ki-67 < 17% had a median TTP of 16 months and median OS of 24 months compared to 7 and 12.5 months respectively for the patients with Ki-67 ≥17%. Significant correlation was found between the ODC, TTP, and OS with age < 52, near total excision, and TMZ doses received ≥ 10. The commonest grade 3 and 4 toxicities was neutropenia recorded in 3 patients (9.67%), thrombocytopenia in 4 patients (12.9%), and one patient with G3 nausea, vomiting, and constipations (3%), all were medically manageable. Conclusion: MGMT promotor methylation status and Ki-67 LI (but not the MGMT protein expression), could serve as prognostic markers for survival, also MGMT could identify the newly diagnosed GBM patients who will have better response to TMZ. [ABSTRACT FROM AUTHOR]

A 3-D, dynamic, non-linear Finite Element Model (FEM) involving contact is used to determine apparent coefficients of friction, μ, for the interaction between the bristles of a flicking brush for street sweeping and concrete. Also, brush contact arcs, as well as suitable brush penetrations as functions of the debris height, are determined for cutting and F128 brushes. Available experimental results are used to determine the coefficients of friction. The bristles are modelled through beam elements, which are subjected to inertia forces. The results suggest that the model is valid and that the coefficient of friction affects the brush vertical force in the flicking brush, but it does not significantly affect its counterpart in the cutting brush. The results also indicate that the coefficient of friction for the flicking brush depends on the sliding velocity, v, and these were fitted to an exponential μ − v curve. [ABSTRACT FROM AUTHOR]

The northeast Nile Delta, Egypt’s most polluted region, appears to have a high incidence of pancreatic cancer. We sought to determine whether there is any geographic clustering of pancreatic cancers there and, if so, whether such clustering might be associated with environmental pollution. Using data from the medical records of the Gastrointestinal Surgical Center of Mansoura University in the Dakahleia Province of Egypt and detailed geographical maps of the northeast Nile Delta region, we plotted the residences of all 373 patients who had pancreatic cancer diagnosed between 1995 and 2000. The study region has 15 administrative districts, whose centroid coordinates, population, and number of pancreatic cancer patients were determined for this study. Monte Carlo simulation identified statistically significant clustering of pancreatic cancer in five subdivisions located near the Nile River and Delta plains. This clustering was independent of population size and formed two larger clusters. When data were analyzed by sex, clustering of pancreatic cancer was observed in the same five subdivisions for men but only two subdivisions showed clustering for women. Together, our data suggest that there is clustering of pancreatic cancer cases in the northeast Nile delta region and that this clustering may be related to water pollution. Our data also warrant future studies of the association between water pollution and pancreatic cancer in the region. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether quantitative flow cytometric androgen receptor density expression (MFC ratio) in prostate cancer was associated with S-phase fraction.Methods: Flow cytometry was performed to determine DNA aneuploidy, S-phase fraction, percentage of androgen receptor (AR)-positive cells, and MFC ratio in prostate cancer patients.Results: MFC ratio showed distinct clustering. Eight patients had a low MFC ratio of 1.78-2.74, while 10 patients had high MFC ratios between 4.99 and 6.48. The S-phase fraction had average values of 11.05 vs 4.92 in tumors with high vs low MFC ratio (P<0.01).Conclusion: S-phase fraction was significantly higher in tumors with high AR density.Prostate Cancer and Prostatic Diseases (2003) 6, 294-300. doi:10.1038/sj.pcan.4500672 [ABSTRACT FROM AUTHOR]

An analysis of the kinetic energy budget is made for a cyclonic development over the Mediterranean. Horizontal flux convergence constitutes a major energy source. Generation of kinetic energy via cross-contour flow is a persistent sink except only a weak energy source for the decay period of our case study. Dissipation of kinetic energy, computed as a residual, has local maxima both in the lower troposphere and near the jet stream level. By investigating the relative importance of divergent and non-divergent components in the kinetic energy budget we found that when calculating the magnitude of the kinetic energy one may safely replace the total wind with the non-divergent one. But the horizontal flux convergence of kinetic energy and the generation of kinetic energy are sensitive to the magnitude of the divergent wind. A large increase in the kinetic energy of the total flow fields and the nondivergent component of the flows occurs over the southeastern Mediterranean with the existence of the subtropical jet. This indicates that the subtropical jet steadily receives energy from divergent flow. Maximum energy conversion and transport occur near the time of maximum storm intensity while smaller values are observed during the development and decay stages. [ABSTRACT FROM AUTHOR]

A new eccentric-cylinder rheometer with guard-ring equipment was constructed as an auxiliary set-up to a Rheometrics Mechanical Spectrometer, type 7200, which enables measurements with the eccentric disk technique. Experimental tests with Newtonian fluids and polymer solutions of relatively low viscosity show that this instrument yields reliable plots of shear viscosity and first normal-stress coefficient over several decades of the effective average shear rate. These coincide very well with plots from a commercial cone-and-plate rheometer even for higher relative eccentricities (up to 0.75). However, no systematic effects of eccentricity, to be expected for higher shear rates, could be observed with these fluids, so that supplementary tests applying fluids with more pronounced viscoelastic properties are to be carried out. [ABSTRACT FROM AUTHOR]

The isothermal, stationary and isochoric flow of a fluid of grade two between a pair of rotating eccentric spheres is investigated. The equations of motion of first and second order are formulated and solved for the first order only. However, the equation of second order indicates the presence of secondary flow. The stress distributions are computed and used to determine the resultant forces and torques acting on the stationary outer sphere. An important result for rheometry is that the resultant torques can be used to determine the coefficient of viscosity, while the resultant force in the direction of the axis of symmetry may be employed to determine the second normal stress difference. [ABSTRACT FROM AUTHOR]

The results of an investigation on the fluidized bed roasting of molybdenite are reported. Molybdenite mixed with quartz was subjected to an oxidizing roast in a 22 mm diam stainless steel batch fluidized bed reactor. Enriched air (with O) or diluted air (with N) was used as the fluidizing and oxidizing gas. In addition to the MoS content of the solids and the O content of the gas, the effect of temperature and flow rate was also examined. For the range of variables investigated, it was found that the temperature influences the rate of the roasting reaction greatly. The gas flow rate affects the conversion favorably up to a certain fluidizing flow rate. An increase in the O content of the gas and the MoS of the solids results in higher conversion levels. The unreacted core kinetic model was applied to the results; and the energy of activation for the reaction was obtained from the Arrhenius plot as 31,100 cal/gmol of MoS. The data obtained should be useful in the design and operation of larger scale roasting reactors. [ABSTRACT FROM AUTHOR]

Bleeding from esophageal varices is a common and serious problem in Schistosomiasis mansoni. A simple and accurate method of detection would facilitate measurement of individual and community morbidity and allow institution of preventive measures. An ultrasonographic scoring system grading periportal fibrosis, portal vein diameter, spleen size, and portasystemic anastomoses was evaluated as a predictor of esophageal varices and a past history of upper gastrointestinal hemorrhage in 43 patients with hepatosplenic schistosomiasis. Ultrasonographic variceal score correlated (r = 0.86, p < 0.001) with the endoscopic variceal grade. Patients with a sonographic score of 5 or greater were highly likely (21 of 23) to have varices of grade II or greater (sensitivity, 91.3%; specificity, 94.7%). Only those with sonographic scores of 5 or greater (15 of 23) had bled from esophageal varices. The ultrasonographic score provided a simple, inexpensive, accurate, and noninvasive means of screening individuals with hepatosplenic schistosomiasis for esophageal varices, and correlated strongly with prior gastrointestinal hemorrhage. It is not known whether a similar score would be useful in hepatic cirrhosis. [ABSTRACT FROM AUTHOR]

The decay ofEu toGd has been studied using H. P. Ge and H. P. Ge−NaI(Tl) spectrometers in coincidence measurements. 141 gamma transitions have been observed. One of these transitions is found to be new and has an energy of 202.5 keV. The 165.9, 202.5, 229.8 and 484.6 keV transitions are placed correctly in the decay scheme ofEu. The levels from this and previous work are compared with those calculated by means of the unified model. [ABSTRACT FROM AUTHOR]

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