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In the light of growing importance of semiconductor nanocrystals for photonics, we report on the growth and characterization of annealed germanosilicate layers used for Ge nanocrystal formation. The films are grown using plasma enhanced chemical vapor deposition (PECVD) and post-annealed in nitrogen at temperatures between 600 and 1200°C for as long as 2h. Transmission electron microscopy (TEM), Raman scattering and photoluminescence spectroscopy (PL) has been used to characterize the samples both structurally and optically. Formation of Ge precipitates in the germanosilicate layers have been observed using Raman spectroscopy for a variety of PECVD growth parameters, annealing temperatures and times. Ge–Ge mode at ~300cm−1 is clearly observed at temperatures as low as 700°C for annealing durations for 45min. Raman results indicate that upon annealing for extended periods of time at temperatures above 900°C; nanocrystals of few tens of nanometers in diameter inside the oxide matrix and precipitation and interdiffusion of Ge, forming SiGe alloy at the silicon and oxide interface take place. Low temperature PL spectroscopy has been used to observe luminescence from these samples in the vicinity of 1550nm, an important wavelength for telecommunications. Observed luminescence quenches at 140K. The photoluminescence data displays three peaks closely interrelated at approximately 1490, 1530 and 1610nm. PL spectra persist even after removing the oxide layer indicating that the origin of the infrared luminescent centers are not related to the Ge nanocrystals in the oxide layer. [ABSTRACT FROM AUTHOR]

The Kayranlik Mountain (Goksun) in Kahramanmaras is a rich resource of an attractive conglomerate with many uses in the construction industry including blocks, shaped stones, pavement, sidewalks and landscape architecture. The paper reports a study to assess their compliance with the relevant Turkish and European Standards and provides correlations between the uniaxial compressive strength, flexural strength, Brazilian tensile strength, water absorption, abrasion and density. [ABSTRACT FROM AUTHOR]

Abstract: In this work, differential geometry of the -graded quantum supergroup is constructed. The corresponding quantum Lie superalgebra is obtained. [ABSTRACT FROM AUTHOR]

The Kayranlik Mountain (Goksun) in Kahramanmaras is a rich resource of an attractive conglomerate with many uses in the construction industry including blocks, shaped stones, pavement, sidewalks and landscape architecture. The paper reports a study to assess their compliance with the relevant Turkish and European Standards and provides correlations between the uniaxial compressive strength, flexural strength, Brazilian tensile strength, water absorption, abrasion and density. [ABSTRACT FROM AUTHOR]

Abstract: Kinetical, morphological and magnetic characteristics of thermally induced martensite in an Fe–30%Ni–3.6%Mo alloy has been studied by scanning electron microscopy, transmission electron microscopy and Mössbauer spectroscopy. Scanning electron microscope and transmission electron microscope observations revealed the occurrence of both athermal and isothermal martensitic transformation in the alloy. In addition, the magnetic properties of both the austenite and martensite phases were determined by the Mössbauer spectroscopy. The Mössbauer spectra showed a paramagnetic character for the austenite phase and an antiferromagnetic character for the martensite phase. [Copyright &y& Elsevier]

The effect of austenitising temperature and cooling rate on the morphology and magnetic properties of martensite in Fe–24·5%Ni–4·5%Si alloy has been studied by means of scanning electron microscopy, Mössbauer spectroscopy and AC susceptibility. Martensite morphology was found to be closely dependent on the austenitising temperature and cooling rate. The changes in volume fraction of martensite and austenite phases, the internal magnetic field of martensite phase and the isomery shift values have been determined by Mössbauer spectroscopy. The Mössbauer study revealed that the martensite volume fractions increased with increasing austenitising temperature and cooling rate. Also internal magnetic field of martensite was decreased by increasing the martensite volume fractions. AC magnetic susceptibility measurements showed that the Neel temperatures TN and the magnetic susceptibility χ increase with increasing austenitising temperatures. [ABSTRACT FROM AUTHOR]

The effect of austenitizing time on the formation of martensite in Fe–24.5%Ni–4.5%Si alloy has been studied by means of transmission electronmicroscope (TEM), scanning electronmicroscope (SEM) and Mössbauer spectroscopy technique. TEM and SEM observations revealed that the martensite morphology was found to be closely dependent on the austenitizing time. The orientation relationship between austenite and thermally induced martensite was found as the Kurdjumov-Sachs type. The volume fraction changes of martensite and austenite phases, the hyperfine magnetic field of martensite phase and isomery shift values have been determined by Mössbauer spectroscopy. The Mössbauer study also revealed that the martensite volume fractions increased with increasing austenite grain size. [ABSTRACT FROM AUTHOR]

PURPOSE: To assess the effectiveness of a hinged ankle-foot orthoses on gait impairments and energy expenditure in children with hemiplegic cerebral palsy (CP) whom orthoses were indicated to control equines. METHOD: Eleven children (seven males, four females) who had a diagnosis of hemiplegic cerebral palsy were included in the study. Each child underwent gait analysis and energy consumption studies with and without ankle-foot orthosis (AFO). The AFOs were all custom-made for the individual child and had plantarflexion stop at 0 degrees with no dorsoflexion stop. The Vicon 512 Motion analysis system was used for gait analysis. Walking energy expenditure measurements were done with breath by breath method using an open-circuit indirect calorimeter (Vmax 29c, Sensormedics, USA). All tests were carried out on the same day with enough resting period. RESULTS: AFO application, as compared with the barefoot condition improved walking speed, stride length and single support time. Double support time was decreased significantly with AFOs and no change in cadance. Ankle dorsiflexion at initial contact, midstance and midswing showed significiant increase. Knee flexion at initial contact was decreased and no significant change in maximum knee extension at stance and maximum knee flexion at swing was obtained. The oxygen consumption was significantly reduced during AFO walking. CONCLUSION: The hinged AFO is useful in controlling dynamic equinus deformity and reducing the energy expenditure of gait in children with hemiplegic spastic cerebral palsy. [ABSTRACT FROM AUTHOR]

Abstract: The thermally induced γ–ɛ and γ–α′ martensitic transformation in Fe–30%Ni–x%Mo alloys with different Mo contents have been studied by transmission electron microscopy (TEM). Observations reveal that α′ martensite is found in alloys containing 0.8, 1.8, and 2.6% Mo, and ɛ martensite in the alloy containing 5%Mo. The first three display the Kurdjumov–Sachs (K–S) orientation relationship between γ and α′, while the other displays the Shoji–Nishiyama (S–N) orientation relationship between γ and ɛ. [Copyright &y& Elsevier]

Abstract: The paramagnetic–magnetically ordered transition and the effect of Mo content on the magnetic properties of martensite phase in Fe–30% Ni–x% Mo alloys have been investigated by AC susceptibility and Mössbauer spectroscopy. The results show that martensitic transformation temperature (M S) indicates the magnetic transition from paramagnetic to magnetically ordered state. Hyperfine magnetic field, isomery shift and volume fractions of phases were determined by Mössbauer spectroscopy. It is also found that volume fraction of thermally induced martensite and M S temperature decreased with the increasing Mo content. [Copyright &y& Elsevier]

This paper presents experimental results obtained from the direct pull-out test using different types of rockbolts having different shape of lugs. These are smooth surface bars, ribbed bars, single conical lugged bars, double conical lugged bars and triple conical lugged bars. It is found that the failure mechanism of the conical lugged rock bolt is different from that of conventional rockbolts, in which the adhesion or the shear strength at the bolt–grout interface provides the load bearing capacity. From the results of experimental study, the use of the conical lugged rock bolts is suggested, because it provides a greater anchorage strength due to wedging effect that is a combination of the shear and compressive strength of the grouting material. [Copyright &y& Elsevier]

This paper represents the result of a project conducted with developing a safe, practical and economical support system for engineering workings. In rock engineering, untensioned, fully cement-grouted rock bolts have been used for many years. However, there is only limited information about the action and the pull-out load capacity of rock bolts, and the relationship between bolt–grout or grout–rock and the influence of the grout properties on the pull-out load capacity of a rock bolt. The effect of grout properties on the ultimate bolt load capacity in a pull-out test has been investigated in order to evaluate the support effect of rock bolts. Approximately 80 laboratory rock bolt pull-out tests in basalt blocks have been carried out in order to explain and develop the relations between the grouting materials and untensioned, fully grouted rock bolts. The effects of the mechanical properties of grouting materials on the pull-out load capacity of a fully grouted bolt have been qualified and a number of empirical formulae have been developed for the calculating of the pull-out load capacity of the fully cement-grouted bolts on the basis of the shear strength, the uniaxial compressive strength of the grouting material, the bolt length, the bolt diameter, the bonding area and the curing time of the grouting material. [Copyright &y& Elsevier]

In this paper we obtain soliton solutions to chiral nonlinear Schrödinger's equation with the Bohm potential by the modified simple equation method and trial equation method. Solitons and shock wave solutions are obtained. Additionally, singular periodic solutions are revealed as a by-product of these approaches and these are also listed. The existence criteria of these form of solutions are also presented. [ABSTRACT FROM AUTHOR]

Abstract: Kinetical, morphological, crystallographical and several thermal properties of thermally induced martensite in the austenite phase of Fe–30% Ni–5% Cu alloy were investigated. Scanning electron microscope (SEM), transmission electron microscope (TEM) and differential scanning calorimetry (DSC) techniques were used during study. Kinetics of the transformation was found to be as athermal type. SEM and TEM observations revealed α′ (BCC) martensite formation in the austenite phase of alloy by thermal effect. These thermally induced α′ martensites exhibited a thin plate-like morphology with twinnings. [Copyright &y& Elsevier]

Objective: The aim of this study was to investigate the effects of cervical traction and exercise in addition to moist heat in thoracic outlet syndrome [TOS]. Methods: Forty patients [28 males, 12 females] with the diagnosis of TOS were randomly divided into two groups. While hot pack and a standard exercise program were applied to one group [the control group], cervical traction was added to that program in the other group [the study group] for 10 sessions. The provocative physical maneuvers were applied to all patients before treatment and after three weeks of the treatment. At follow-up, every patient was questioned with a Likert scale [no cure, little, moderate, much, very much]. Results: After a rehabilitation program, improvements in Adson, hyperabduction, and hyperextension maneuvers were statistically significant in both groups [P < 0.05]. While improvements in Roos, costoclavicular, Wright's maneuvers, and Erb tenderness were statistically significant in the study group [P < 0.05], they were not found significant in the control group [P > 0.05]. Improvement in pectoral tenderness was not statistically significant in either group [P > 0.05]. Improvement in pain was not statistically significant between the groups [90 percent versus 75 percent, P > 0.05]. Difference in numbness scores between the groups was statistically significant in favor of the study group [80 percent versus 20 percent, P < 0.001]. Conclusions: We suggest that hot pack and exercise together achieve some improvements in TOS. However, cervical traction in addition to exercise and hot pack obtains additional benefits in the conservative management of TOS. [ABSTRACT FROM AUTHOR]

Hyperglycemia increases reactive oxygen species (ROS) and the resulting oxidative stress contributes to the development of diabetic complications. Dexpanthenol (Dxp) is the biological active form of pantothenic acid. We investigated whether Dxp administration could decrease oxidative stress as a way to treat renal complications of diabetes mellitus (DM). Thirty-two male Wistar albino rats were divided into four groups: control, Dxp, DM and DM + Dxp. Experimental diabetes was induced by a single dose of streptozotocin (STZ). After administration of STZ, the DM + Dxp group was administered 500 mg/kg Dxp intraperitoneally every day for 6 weeks. At the end of the study, blood glucose levels were measured and rats were sacrificed. Kidneys were embedded in paraffin, sectioned and stained with hematoxylin and eosin, and periodic acid-Schiff. The mean malondialdehyde levels, glutathione peroxidase, superoxide dismutase and catalase activities, and total antioxidant and total oxidant status also were measured. The control group was normal in histological appearance. We observed congestion, inflammation, glomerulosclerosis, tubular desquamation, loss of villi and hydropic degeneration in tubule cells in the DM group. Indicators of oxidative stress were elevated and antioxidant activity was reduced in the DM group compared to controls. In the DM + Dxp group, oxidative stress was decreased, antioxidant activity was increased and histopathological changes were reduced compared to the DM group. We found that Dxp exhibited ameliorative effects on STZ induced diabetic nephropathy by increasing antioxidant activity. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) sequestered in saline aquifers undergoes a variety of chemically-coupled mechanical effects, which may cause CO 2 -induced mechanical changes and time-dependent reservoir deformation. This paper investigates the mineralogical and microstructural changes that occur in reservoir rocks following injection of CO 2 in deep saline aquifers and the manner in which these changes influence the mechanical properties of the reservoir rocks. In this study, cylindrical sandstone specimens, 38 mm in diameter and 76 mm high, obtained from the Gosford basin, were used to perform a series of unconfined compressive strength (UCS) tests. Different saturation conditions: dry, water- and brine-saturated sandstone samples with and without scCO 2 (super-critical carbon dioxide) injection, were considered in the study to obtain a comprehensive understanding of the impact of scCO 2 injection during the CO 2 sequestration process on saline aquifer mechanical properties. An acoustic emission (AE) system was employed to identify the stress threshold values of crack closure, crack initiation and crack damage for each testing condition during the whole deformation process of the specimens. Finally, scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses were performed to evaluate the chemical and mineralogical changes that occur in reservoir rocks during CO 2 injection. From the test results, it is clear that the CO 2 -saturated samples possessed a lower peak strength compared to non-CO 2 saturated samples. According to SEM, XRD and XRF analyses, considerable quartz mineral corrosion and dissolution of calcite and siderite were observed during the interactions of the CO 2 /water/rock and CO 2 /brine/rock systems, which implies that mineralogical and geochemical rock alterations affect rock mechanical properties by accelerating the collapse mechanisms of the pore matrix. AE results also reveal the weakening effect of rock pore structure with CO 2 injection, which suggests a significant effect of CO 2 on failure mechanisms of the reservoir rock, with CO 2 saturation showing a significant influence on crack initiation and crack damage stages. [ABSTRACT FROM AUTHOR]

The petroleum industry spends millions of dollars each year to prevent and overcome sand control problems and their prediction has therefore become essential to minimize the adverse effects of sand production. This paper reviews existing experimental and modelling studies of the prediction of sand production. In experimental studies, the trapdoor system has been commonly used. The early experimental set-ups had a simple trapdoor configuration with a fluid inlet port to inject a single fluid to conduct qualitative tests. Other facilities were added over time, including facilities to conduct qualitative and quantitative tests, inject radial, axial and multiphase fluids and conduct tests in uniaxial and tri-axial stress environments. Experimental findings on sand production can be categorized into four different effects: the flowing fluid characteristics effect, the material characteristics effect, the loading effect, and the outlet size effect. However, the application of laboratory findings to field conditions has become doubtful due to the various assumptions used in laboratory studies, including the scaling down of the reservoir, the use of sieved river sands and/or synthetic samples, and the use of limited combinations of two-phase flows. In model development, some basic mechanisms have been recognized as responsible for sand production: shear and tensile failure, the critical pressure gradient and drawdown pressure, and erosion. Tensile failure occurs when the effective minimum principle stress applying on the rock mass reaches its tensile strength, and shear failure occurs when the applied stress on some planes in the wellbore area is higher than their bearing capacity. Reduction of reservoir pressure causes the effective hydrostatic stresses on it to be increased, breaking its pore structure, and the rock formation can be eroded internally and externally, producing sand by dynamic seepage drag forces. To date, both continuum and discrete element method (DEM) approaches have been considered in sand production models. Most approaches have been developed considering the hydro-mechanical or shear failure mechanisms and some have combined them. [ABSTRACT FROM AUTHOR]

A 58 year old man was admitted with a complaint of chest pain upon exertion during the previous 10 days. The patient was hospitalised with a diagnosis of unstable angina. Following stabilization with medical treatment, coronary angiography was performed. In the right coronary artery (RCA), consecutive non-significant lesions in the mid segment and severe stenosis on the posterior descending artery bifurcation in the RCA at the left anterior oblique position were determined. Slow contrast progression was observed in the region of the conus artery at the same position.

We report a 22-yr-old man who was admitted to our inpatient rehabilitation center 17 mos after a traumatic brain injury (TBI). He was also diagnosed to have bilateral sciatic nerve entrapment attributable to hip heterotopic ossification (HO). Presenting the first report of a sciatic nerve entrapment secondary to a HO in TBI, we herein discuss the concurrence of a lower-motor nerve problem in a patient with an upper-motor nerve injury. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Heart rate variability dynamics during controlled hypotension with nicardipine, remifentanil and dexmedetomidine," by S. Shin, J. W. Lee, S. H. Kim, Y. S. Jung, and Y. J. Oh in the 2013 issue.