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This research paper reports a high frequency Third Order Electronically Tunable Quadrature Oscillator (TOETQO) using an active element termed as Dual-X Current Conveyor Transconductor Amplifier (DXCCTA) in which active element MOS and passive Capacitor (C) contribute the implementation performance of the proposed design as MOS-C TOETQO. Due to the presence of DXCCTA with active grounded capacitor and MOS-based resistor, the proposed quadrature oscillator facilitates a suitable design for integrated circuits (ICs). The proposed TOETQO circuit produces current as well as voltage outputs simultaneously. Moreover, the non-ideal analysis of the proposed oscillator circuit is also included. The proposed design shows a good agreement for the oscillation criteria due to the acceptable limit of %THD and gives the variation in frequency of oscillation (up to MHz) values with respect to bias current. Moreover, by keeping the bias current constant, frequency of oscillation can also be electronically tuned independently by varying the values of resistor. Finally, Cadence simulation results are depicted to verify the theoretical analyses and practical feasibility of proposed TOETQO design is also well verified with experimental set up by using IC AD844 and CA3080. A fair comparison of the proposed quadrature oscillator with existing literatures is also tabulated. [ABSTRACT FROM AUTHOR]

The current work investigates the reciprocating wear behavior of surface mechanical attrition–treated (SMAT) AISI 316L stainless steel with and without polymer and composite coatings. The high-performance aromatic thermoset polymer (ATSP) and its composite with MoS2 are deposited on non-SMATed and SMATed steel using the spin coating technique. Further, a reciprocating wear test is performed on non-SMATed, SMATed, and coated surfaces against an alumina ball using different loads and reciprocation cycles. Enhanced surface hardness (∼89%), presence of an α′ (body-centered cubic [bcc] Fe) phase, and lower oxidation during reciprocation cause a decrease in wear loss and coefficient of friction (COF) of the SMATed surface by ∼37, and ∼20%, respectively, under 15 N load and most extended reciprocation cycle. The wear loss and COF of the steel are further reduced by depositing ATSP polymer and ATSP-MoS2 composite coatings. The adhesion and durability of coatings are enhanced by the SMAT process. This enhanced durability lowers the wear loss and COF of ATSP and ATSP-MoS2 composite coatings when deposited on the SMATed substrate. Polymer coating reduces the COF of non-SMATed and SMATed steel by ∼68 and ∼85%, respectively. Depending on the concentration of MoS2 in the composite coating, the COF ranges from 0.04 to 0.32 and from 0.02 to 0.07 for non-SMATed and SMATed specimens, respectively. The best performance of a composite coating was observed at ∼10 wt% MoS2. The COF of composite coated steel is ∼96% lower than that of the noncoated and nontreated steel surface. The SMAT processing of substrate and ATSP-MoS2 composite coating considerably enhances the tribological performance of AISI 316L steel. [ABSTRACT FROM AUTHOR]

The present study deals with the properties of boronized and non-boronized low-alloy steel (34CrAlMo5-10). Specimens are characterised using microscopy, various spectroscopic techniques, nanoindentation, surface profilometer, and tribometer. The boronized region contains (i) (Fe, M)2B columns and (ii) matrix between the columns. Nanoindentation study reveals the difference in the mechanical behaviour of boride, matrix, and core regions. Strain-rate sensitivity of different regions of the specimen cross-section varies between 0.005 and 0.011. The boride phase is more sensitive to the strain-rate than matrix and core. The room-temperature oxidation resistance of the steel surface is enhanced by the presence of a higher proportion of mixed-boride and the oxide layer enriched with Cr2O3. At 550 and 850°C, boronized specimens have higher oxidation resistance than the non-boronized specimens, where the layer of iron-borates protects the surface. At 200°C, the boronized specimen has deprived oxidation resistance. Amongst the investigated wear-parameters, the maximum and minimum wear-resistance of the boronized surface is about 46 and 8 times the wear-resistance of the non-boronized surface, respectively. A steeper drop in the tribological advantage gained by the boronizing treatment is perceived with the increase in load, especially under higher sliding speed. [ABSTRACT FROM AUTHOR]

Since the mid-1990s, the aim of keeping climate change within 2 °C has become firmly entrenched in policy discourses. In the past few years, the likelihood of achieving it has been increasingly called into question. The debate around what to do with a target that seems less and less achievable is, however, only just beginning. As the UN commences a two-year review of the 2 °C target, this article moves beyond the somewhat binary debates about whether or not it should or will be met, in order to analyse more fully some of the alternative options that have been identified but not fully explored in the existing literature. For the first time, uncertainties, risks, and opportunities associated with four such options are identified and synthesized from the literature. The analysis finds that the significant risks and uncertainties associated with some options may encourage decision makers to recommit to the 2 °C target as the least unattractive course of action. [ABSTRACT FROM AUTHOR]

The effects of Ocimum sanctum (Lamiaceae), Tulsi on the cellular oxidative state in a hepatocyte cell line (HepG2) and its putative potency to enhance endogenous antioxidant defenses were investigated. Cells were incubated with aqueous extracts of Tulsi (1–100 μg·ml−1) between 4 and 48 h, and biochemical markers of OS were determined. Tulsi up to 100 μg·ml−1 concentrations had no effect either on cytotoxicity or cell proliferation but increased the levels of glutathione (18%–32%) and antioxidant capacity (19%–31%) of cells and enhanced activities of endogenous antioxidant enzymes. Results suggested that aqueous extract of Tulsi reduced the basal OS in HepG2 cells, by induction of antioxidant enzymes and enhancing levels of antioxidant molecules either of which can potentially effect faster dissipation of ROS. [ABSTRACT FROM AUTHOR]

Context: Amla [ Emblica officinalis Gaertn. (Euphorbiaceae)], a major constituent of several herbal formulations, is a well-known hepatoprotectant. Despite its extensive use, mechanistic understanding of its antioxidant action is rather limited. Objective: In the current study, we investigated the effects of E. officinalis extracts (from dried fruits) on cellular oxidative state using a hepatocyte cell line (HepG2). We hypothesize that E. officinalis aqueous extracts have potency to modulate basal oxidative markers and enhance endogenous antioxidant defenses. Materials and methods: Cells were incubated with aqueous extracts of E. officinalis (1-100 μg/ml) for varied time points (4-24 h) and biochemical markers of oxidative stress were determined in cell lysate. Discussion: Aqueous extracts of E. officinalis at 100 μg/ml can significantly modulate the basal levels of oxidative markers and enhance antioxidant defenses of the cells. Conclusions: Our findings clearly indicate the propensity of E. officinalis aqueous extracts to improve endogenous antioxidant defenses in HepG2 cells. Although further studies are required to assess their efficacy under experimentally induced oxidative, our data suggest that the hepatoprotective effects of E. officinalis reported earlier may be largely due to its potential to enhance the antioxidant defenses in vivo. Results: Because E. officinalis up to 100 μg/ml concentrations had no effect on cell viability; it was considered noncytotoxic. Incubation with E. officinalis for 24 h resulted in significant diminution in the levels of lipid hydroperoxide (18-42%) and reactive oxygen species (11-29%). Furthermore; E. officinalis increased the levels of glutathione (GSH; 18-32%); antioxidant capacity (19-31%); and activities of antioxidant enzymes (superoxide dismutase; 25-41%; catalase; 39-50%; GSH peroxidase; 20-35%; GSH reductase; 26-35%; and GSH S-transferase; 12-30%). [ABSTRACT FROM AUTHOR]

The Liberation Tigers of Tamil Eelam (LTTE) are a guerilla/terrorist group representing the minority Tamil community, fighting for an Eelam, or homeland in the northern and eastern provinces of Sri Lanka. Led by V. Pirabhakaran, the group started as a small forty to fifty man outfit in the early 1980s, but has since grown to an organization of several thousand. A unique, if macabre feature of its tactics has been the use of suicide commandos, both men and women, some in their early teem, for individual assassination as well as mass attacks. A former Indian prime minister, a Sri Lankan president, and several top aides have been targeted and killed in this way. The LTTE has not hesitated to kill prominent Sinhala civilians. Between 1987 and 1990 LTTE fought the Indian Army, which was sent to disarm it as part of an Indian-Sri Lankan agreement. After the Indian pullout in 1990, the organization used a suicide bomber to carry out the assassination of former Indian Prime Minister Rajiv Gandhi. Thereafter Indian authorities unravelled a well-organized network of safe houses, supporters, and logistics depots in Tamil Nadu. India maintains a strict naval cordon sanitaire around the area of conflict, which shows no signs of abating. [ABSTRACT FROM AUTHOR]