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Abstract: Ferroelectric SrBi2Ta2O9 (SBT) thin films were grown on p-type (100) Si substrates by radio frequency sputtering technique. The crystallinity of the films was studied using grazing incidence X-ray diffraction pattern. The spectra showed the films were polycrystalline with dominant orientation along (115) plane. The surface morphology was investigated by atomic force microscope. The chemical composition was studied by Rutherford back-scattering, which yielded a near stoichiometric composition of SBT. The capacitance–voltage characteristics of Al/SBT/Si capacitors measured at 100kHz showed a hysteresis nature with a clockwise rotation and the memory window of the hysteresis loop was 0.88V with the gate voltage ±5V. The interface trap density was calculated by using Hills method at room temperature and a value in the order of 1011–1012 eV−1 cm−2 was found depending on the crystallization temperature at midgap region. [Copyright &y& Elsevier]

The GEFSOC Project developed a system for estimating soil carbon (C) stocks and changes at the national and sub-national scale. As part of the development of the system, the Century ecosystem model was evaluated for its ability to simulate soil organic C (SOC) changes in environmental conditions in the Indo-Gangetic Plains, India (IGP). Two long-term fertilizer trials (LTFT), with all necessary parameters needed to run Century, were used for this purpose: a jute (Corchorus capsularis L.), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) trial at Barrackpore, West Bengal, and a rice–wheat trial at Ludhiana, Punjab. The trials represent two contrasting climates of the IGP, viz. semi-arid, dry with mean annual rainfall (MAR) of <800mm and humid with >1600mm. Both trials involved several different treatments with different organic and inorganic fertilizer inputs. In general, the model tended to overestimate treatment effects by approximately 15%. At the semi-arid site, modelled data simulated actual data reasonably well for all treatments, with the control and chemical N+farm yard manure showing the best agreement (RMSE=7). At the humid site, Century performed less well. This could have been due to a range of factors including site history. During the study, Century was calibrated to simulate crop yields for the two sites considered using data from across the Indian IGP. However, further adjustments may improve model performance at these sites and others in the IGP. The availability of more long-term experimental data sets (especially those involving flooded lowland rice and triple cropping systems from the IGP) for testing and validation is critical to the application of the model''s predictive capabilities for this area of the Indian sub-continent. [Copyright &y& Elsevier]

The Global Environment Facility co-financed Soil Organic Carbon (GEFSOC) Project developed a comprehensive modelling system for predicting soil organic carbon (SOC) stocks and changes over time. This research is an effort to predict SOC stocks and changes for the Indian, Indo-Gangetic Plains (IGP), an area with a predominantly rice (Oryza sativa)–wheat (Triticum aestivum) cropping system, using the GEFSOC Modelling System and to compare output with stocks generated using mapping approaches based on soil survey data. The GEFSOC Modelling System predicts an estimated SOC stock for the IGP, India of 1.27, 1.32 and 1.27Pg for 1990, 2000 and 2030, respectively, in the top 20cm of soil. The SOC stock using a mapping approach based on soil survey data was 0.66 and 0.88Pg for 1980 and 2000, respectively. The SOC stock estimated using the GEFSOC Modelling System is higher than the stock estimated using the mapping approach. This is due to the fact that while the GEFSOC System accounts for variation in crop input data (crop management), the soil mapping approach only considers regional variation in soil texture and wetness. The trend of overall change in the modelled SOC stock estimates shows that the IGP, India may have reached an equilibrium following 30–40 years of the Green Revolution. This can be seen in the SOC stock change rates. Various different estimation methods show SOC stocks of 0.57–1.44Pg C for the study area. The trend of overall change in C stock assessed from the soil survey data indicates that the soils of the IGP, India may store a projected 1.1Pg of C in 2030. [Copyright &y& Elsevier]

Abstract: Exposure to environmental toxins increases the risk of neurodegenerative diseases including Parkinson’s disease (PD). Rotenone is a neurotoxin that has been used to induce experimental Parkinsonism in rats. We used the rotenone model of experimental Parkinsonism to explore a novel aspect of extra-nigral degeneration, the neurodegeneration of spinal cord (SC), in PD. Rotenone administration to male Lewis rats caused significant neuronal cell death in cervical and lumbar SC as compared with control animals. Dying neurons were motoneurons as identified by double immunofluorescent labeling for terminal deoxynucleotidyl transferase, recombinant–mediated dUTP nick-end labeling-positive (TUNEL+) cells and choline acetyltransferase (ChAT)-immunoreactivity. Neuronal death was accompanied by abundant astrogliosis and microgliosis as evidenced from glial fibrillary acidic protein (GFAP)-immunoreactivity and OX-42-immunoreactivity, respectively, implicating an inflammatory component during neurodegeneration in SC. However, the integrity of the white matter in SC was not affected by rotenone administration as evidenced from the non co-localization of any TUNEL+ cells with GFAP-immunoreactivity and myelin basic protein (MBP)-immunoreactivity, the selective markers for astrocytes and oligodendrocytes, respectively. Increased activities of 76 kD active m-calpain and 17/19 kD active caspase-3 further demonstrated involvement of these enzymes in cell death in SC. The finding of ChAT+ cell death also suggested degeneration of SC motoneurons in rotenone-induced experimental Parkinsonism. Thus, this is the first report of its kind in which the selective vulnerability of a putative parkinsonian target outside of nigrostriatal system has been tested using an environmental toxin to understand the pathophysiology of PD. Moreover, rotenone-induced degeneration of SC motoneuron in this model of experimental Parkinsonism progressed with upregulation of calpain and caspase-3. [Copyright &y& Elsevier]

Abstract: In contrast to generally observed non-acidic and less weathered Mollisols in temperate semi-arid and humid climate, acidic and fairly weathered Mollisols on Deccan basalt are observed in hills of central (Satpura Range, Madhya Pradesh) and Western India (Western Ghats, Maharashtra) under forest in the present tropical humid climatic conditions. The detailed morphological, chemical and mineralogical investigations of these Mollisols of central and western India indicates that due to the presence of zeolites in the Deccan basalt, the transformation of smectite to kaolinite was prevented and the retention of adequate amount of smectite and continuous supply of calcium ions from zeolites made the formation of Mollisols in forest even under tropical humid climate. The formation and the persistence of these Mollisols in association with acidic Alfisols under sparse forest in the basaltic landscape of millions of years in central and western India demonstrates the primary importance of the quality of parent material rich in expanding clay mineral and bases in their formation. This unique example thus expands the basic knowledge on the formation of Mollisols in the humid tropical part of the world. [Copyright &y& Elsevier]

Abstract: Cluster assembled selenium oxide (SeO2) thin films, as a function of oxygen flow pressure (OFP) have been synthesized by a low energy cluster beam deposition (LECBD) technique. The OFP dependent surface morphology leading to well separated nanoclusters (size ranging from 50 to 200nm) and fractal features are confirmed from transmission electron microscopic (TEM) measurements. A diffusion limited aggregation (DLA) mediated fractal growth with dimension as 1.71±0.01 has been observed for high OFP (60mbar). Structural analysis by glancing angle X-ray diffraction (GXRD) and selected area diffraction (SAD) studies identify the presence of tetragonal phase SeO2 in the deposit. Micro-Raman studies indicate the shifts in bending and stretching vibrational phonon modes in cluster assembled SeO2 as compared to their bulk counter part due to the phonon confinement effect. [Copyright &y& Elsevier]

Abstract: Glioblastoma is the most malignant and prevalent brain tumor that still remains incurable. Recent studies reported anti-cancer effect of the broccoli-derived compound sulforaphane. We explored the mechanisms of sulforaphane-mediated apoptosis in human glioblastoma T98G and U87MG cells. Wright staining and ApopTag assay confirmed apoptosis in glioblastoma cells treated with sulforaphane. Increase in intracellular free Ca2+ was detected by fura-2 assay, suggesting activation of Ca2+-dependent pathways for apoptosis. Western blotting was used to detect changes in expression of Bax and Bcl-2 proteins resulting in increased Bax:Bcl-2 ratio that indicated a commitment of glioblastoma cells to apoptosis. Upregulation of calpain, a Ca2+-dependent cysteine protease, activated caspase-12 that in turn caused activation of caspase-9. With the increased Bax:Bcl-2 ratio, cytochrome c was released from mitochondria to cytosol for sequential activation of caspase-9 and caspase-3. Increased calpain and caspase-3 activities generated 145 kD spectrin breakdown product and 120 kD spectrin breakdown product, respectively. Activation of caspase-3 also cleaved the inhibitor-of-caspase-activated-DNase. Accumulation of apoptosis-inducing-factor in cytosol suggested caspase-independent pathway of apoptosis as well. Two of the inhibitor-of-apoptosis proteins were downregulated because of an increase in ‘second mitochondrial activator of caspases/Direct inhibitor-of-apoptosis protein binding protein with low pI.’ Decrease in nuclear factor kappa B and increase in inhibitor of nuclear factor kappa B alpha expression favored the process of apoptosis. Collectively, our results indicated activation of multiple molecular mechanisms for apoptosis in glioblastoma cells following treatment with sulforaphane. [Copyright &y& Elsevier]

Abstract: We have studied microstructural, magnetic and electrical transport properties of melt-spun Cu90Co5Fe5 granular alloys. XRD results show the phase formation and the decomposition of the Cu–Co (Fe) solid solution, occurred by the annealing of the samples at a certain temperature. AFM (atomic force microscopy) investigation demonstrates the distribution of particles size and MFM (magnetic force microscopy) directly shows the ferromagnetic granules on the copper matrix. These results are corroborated by the magnetic properties of the samples. Magnetic and electrical transport properties have been studied in the temperature range 15–300 K through ac susceptibility and dc resistivity measurements in the presence of magnetic field. The measured magnetoresistance of the samples reaches the highest value at an optimum annealing temperature. [Copyright &y& Elsevier]

Abstract: The interfacial characteristics of high-κ HfO2 on NH3- and N2O-plasma treated p-Si substrates have been investigated using high-resolution transmission electron microscopy (HRTEM), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), and auger electron spectroscopy (AES). NH3- and N2O-plasma treated films show the formation of a nitrogen-rich Hf-silicate interfacial layer between the deposited HfO2 and Si substrates. The electrical characteristics have been studied using metal–oxide-semiconductor (MOS) structures. Interfacial nitrogen increases the capacitances by ∼33% for NH3 and ∼47% for N2O-treated Si as compared to the untreated surface. A dielectric constant of ∼26 for HfO2 film, ∼6.0 for Hf-silicate, ∼9.0 for NH3- and ∼11.0 for N2O-treated interfacial layers have been calculated from the accumulation capacitances of the MOS capacitors. The relatively higher dielectric constant, lower capacitance equivalent thickness (CET), lower leakage current and higher breakdown voltage for N2O-plasma treated film makes it attractive for scaled Si MOSFET applications. [Copyright &y& Elsevier]

Abstract: A pinion, which was a part of an air-motor driving a diesel generator (DG) of a power plant’s emergency power-supply system, was found to have failed into three parts during a routine check-up of the DG. This pinion, attached to the air-motor shaft is active only for a short duration during the start up, when the motion of the air-motor shaft is transferred to the ring gear attached to the DG which in turn starts the DG. Once the DG has started, the pinion disengages from the ring gear and the air-motor stops. The pinion that failed had been in operation for a long time and experienced several start-up operations before failure. A systematic failure analysis was carried out to find out the reasons for this unexpected fracture of the pinion during operation. The results indicate that the fracture was caused by fatigue with a fatigue crack initiating from the fillet of one of the pinion teeth. Due to misalignment that was present, the pinion did not mesh properly with the ring gear during the start-up operation and this led to a high stress concentration at the root of the pinion. The misalignment also led to severe wear and excessive heat generation at the mating surface. Misalignment, improper heat treatment, non-uniform distribution of sulphide inclusions and sharp corners would have all contributed to the failure of the pinion. [Copyright &y& Elsevier]

Abstract: Ultrathin (&#60;100Å) oxynitrides were grown on strained Si0.74Ge0.26/Si heterolayers by low energy plasma source nitrogen implantation followed by microwave plasma oxidation at a low temperature. Secondary ion mass spectroscopy analysis revealed the incorporation of nitrogen into the strained Si0.74Ge0.26/Si heterolayers, forming good quality oxynitride films upon plasma oxidation. Though the fixed oxide and interface charge densities are relatively high, grown films exhibit low leakage current and high breakdown field strength (6–9MV/cm), indicating that the oxynitrides formed by plasma source nitrogen implantation are suitable for metal-oxide-semiconductor devices. [Copyright &y& Elsevier]

Approximately 5% of spinal cord injuries in the US occur in patients younger than 16 years. These young patients have an increased mortality within the 24 h after trauma but have a greater capacity for functional recovery than adults, suggesting age-related differences in injury tolerance. Unfortunately, the response of the developing cord to secondary injury has not been thoroughly investigated. Calpain, a Ca2+-dependent protease, has been implicated in the pathogenesis of spinal cord injury (SCI) in rats. Our current investigation revealed that following SCI, calpain upregulation was qualitatively less in the 21-day-old rats than in adult rats, as shown by immunofluorescent labeling. Decreased levels of TUNEL+ neurons were also noted in juvenile rat spinal cord, indicating that the developing cord may have an increased resistance to injury. [Copyright &y& Elsevier]

Studies of stimulated THz emission from boron-doped Si/Si1−xGex/n-Si quantum-well (QW) structures of various potential and doping profiles are presented. In the single-QW structures with the optical resonator, the stimulated THz emission is observed only for Ge content x=0.07, 0.1, and 0.15. Two different regimes for excitation of the emission are observed in the same sample depending on charging the surface and thermal ionization of donors in the substrate. [Copyright &y& Elsevier]

Presents an overview of an advanced multichip module technology for high-performance IBM UNIX-class servers. Fabrication of the technology; Insight on the assembly testing; Reliability qualification of the technology.

• Characterising crack growth resistance of IF steel sheet by energy dissipation rate. • New method proposed for determining stationary energy dissipation rate, R ∞ • Simulation of R - Δ a curves by cohesive zone modelling in DENT and SENT specimens. • Normalizing o f R - Δ a curves resolved geometry dependence of energy dissipation rate. The present study aims at charactering the crack growth resistance parameter in an 1 mm thick interstitial-free (IF) steel sheet using the energy dissipation rate parameter, R. The R - Δ a plots of single-edge and double-edge notched tension specimens have been determined with only additional computations of mechanical and optical test data already generated in the course of determining the variation of crack tip opening angle with Δ a following the optical method of ASTM E 2472. A new method has been adopted for determining the stationary value of energy dissipation rate, R ∞ , This has been done by analyzing mechanical test data generated in the course of essential work fracture (EWF) testing, with additional inputs on crack initiation points identified in those EWF tests. An attempt has been made to normalize the R - Δ a plots in order to reduce the specimen geometry dependence of the energy dissipation results. [ABSTRACT FROM AUTHOR]

• Evaluation of EWF parameters for IF steel by testing SENT specimens. • Transferability of EWF parameters between SENT and DENT specimen geometry. • Notch size dependence of EWF parameters in case of SENT specimens. • 3D-Cohesive Zone Modellingfor crack propagation in SENT specimens. Ductile tearing resistance of a 1 mm thick interstitial free steel sheet has been characterized using single edge notched tensile (SENT) specimens with or without fatigue precracks at quasistatic strain rates. In this study, the critical Crack Tip Opening Angle (CTOA), and also crack initiation parameters, namely the initiation energy per unit ligament area (w i), critical value for the J -integral (J c), and critical crack tip opening displacement (δ c) have been examined and compared with the corresponding parameters from the Essential Work of Fracture (EWF) method. Dependence of these parameters on specimen geometry has also been examined. The EWF paradigm has been extended to the initial mixed-constraint regime of crack extension. 3D cohesive zone modelling for flat fracture becomes reasonably successful in simulating crack growth in the SENT specimens. [ABSTRACT FROM AUTHOR]

• Tearing resistance characterisation by SENT and DENT specimen of IF steel sheet. • Transferability of CTOA tearing resistance data between SENT and DENT geometry. • Reduce experimental burden to characterise tearing resistance for thin sheet. • Cohesive zone modeling corroborates experimental tearing resistance data. The present study addresses characterizing ductile tearing resistance of a 1 mm thick sheet of an interstitial free steel sheet using crack tip opening angle (φ), and δ 5 concepts. The transferability of the φ - crack growth (Δ a) data between two geometry, namely single edge notch tensile (SENT) and double edge notch tensile (DENT), was verified. For a specified thickness the δ 5 - Δ a data can also be used as a material parameter. Cohesive zone modeling (CZM) successfully reproduced the experimentally determined φ - Δ a and δ 5 - Δ a plots for pre-cracked specimens, and confirmed transferability of the CZM parameters between the two geometries. [ABSTRACT FROM AUTHOR]

Eu3+-doped BST (65:35), and BST (80:20) were prepared at different compositional ratios of BaTiO3, SrTiO3 and Eu2O3. Both structural and microsurface analyses were done using X-ray diffraction and scanning electron microscopy, respectively. The photoluminescence (PL) properties of doped samples were investigated at room temperature. The presented measurements monitor the emission wavelengths of the Eu2O3 with emission peaks at 617, 667, and 695 nm. The structural difference between both kinds of doped samples accounts for the intensification of the luminescence intensity. [Copyright &y& Elsevier]

Metal-oxide-semiconductor capacitors with a trilayer structure consisting of the cap gate oxide, sputtered SiGe layers and thermally grown tunnel oxide were fabricated on p-Si substrates. The trilayer structures were rapid thermal annealed at 1000 °C in nitrogen atmosphere for different durations. Cross-sectional transmission electron micrographs revealed the complete isolation of Ge nanocrystals in the sandwiched structure annealed for a longer duration. The optical and charge storage characteristics of trilayer structures were studied through photoluminescence spectroscopy and capacitance-voltage measurements, respectively. Under optimized annealing conditions, an enhancement of the charge storage capability of nanocrystals was observed in agreement with the optical emission characteristics. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

• Estimation of CTOA using EWF test is recommended for sheet steels. • The method has been applied for DP 780 grade automotive steel sheet (thickness = 1 mm). • The estimated CTOA is independent of machined notch tip radius of DENT specimen. • The essential work of fracture and estimated CTOD depends on notch tip radius. The Essential Work of Fracture (EWF) method is adopted to study the ductile tearing resistance of Dual-Phase steel (DP 780) sheet of 1 mm nominal thickness. All the three characterizing parameters, namely EWF, estimate of crack tip opening displacement (CTOD) for crack initiation and crack tip opening angle (CTOA), that can be determined by the EWF testing paradigm have been examined. It is concluded that, of these three parameters, the CTOA estimated by this easy and rapid procedure is the best choice both in terms of statistical robustness and for potential application in integrity assessment. [ABSTRACT FROM AUTHOR]

Metal-oxide-semiconductor structures with germanium nanocrystals embedded in the oxide matrix have been fabricated by rf sputtering followed by rapid thermal annealing. The cross-sectional transmission electron micrographs of the structure provide a clear indication of the formation of isolated germanium nanocrystals sandwiched between tunnelling and cap gate oxides. The optical properties of the structure studied by photoluminescence spectroscopy show the emission in the visible range due to quantum confinement of carriers. The C-V measurements of the trilayer structure have been used to demonstrate the charge storage characteristics in the Ge nanocrystals. [ABSTRACT FROM AUTHOR]