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The land use types and soil management have a significant effect on soil properties. However, their impact on the stratification of soil properties, carbon management index (CMI) and soil degradation index (SDI) is still poorly documented in coastal light soils of south-eastern India. Soil samples were collected from six divergent land use types, Sugarcane (SC), Fallow-Tobacco (F-T), Paddy-Maize-Fallow (P-M-F), Eucalyptus + Bamboo (AF), Oil Palm (OP), and Forest (NF). The soil samples were collected at 0–5, 5–15, 15–30, and 30–45 cm soil depths, and contents of total organic carbon (TOC), labile organic carbon (LC), non-labile organic carbon (NLC), total nitrogen (TN), their stocks, stratification ratios (SRs), CMI, and SDI were determined. Results showed that the contents of TOC, LC, NLC, and TN in NF were significantly higher followed by OP, whereas the parameters were lower in F-T followed by P-M-F. The proportion of SOC and N stocks under NF were higher than F-T by 56.6% and 50.3%, respectively. With NF as a reference, the mean CMI followed the order of OP (78) > AF (60) > SC (59.5) > P-M-F (43.8) > F-T (36.3). The SR values of SOC and TN were highest (1.34 to 2.70) for NF, whereas it was lowest (1.10 to 1.54) in F-T in all soil depths. The highest cumulative SDI of −133.2% was observed in F-T followed by P-M-F (−117%). The CMI, SRs were lower and SDI was higher under F-T and P-M-F indicating poor soil quality and its degradation. [ABSTRACT FROM AUTHOR]

This paper presents a high-order computational scheme for numerical solution of a time-fractional diffusion equation (TFDE). This scheme is discretized in time by means of L1-scheme and discretized in space using a compact finite difference method. Stability analysis of the method is discussed. Further, convergence analysis of the present numerical scheme is established and we show that this scheme is of O (Δ t 2 - α + Δ x 4) convergence, where α ∈ (0 , 1) is the order of fractional derivative (FD) appearing in the governing equation and Δ t and Δ x are the step sizes in temporal and spatial direction, respectively. Three numerical examples are considered to illustrate the accuracy and performance of the method. In order to show the advantage of the proposed method we compare our results with those obtained by finite element method and B-spline method. Comparison reveals that the proposed method is fast convergent and highly accurate. Moreover, the effect of α on the numerical solution of TFDE is investigated. The CPU time of the present method is provided. [ABSTRACT FROM AUTHOR]

This paper presents an efficient numerical technique for solving a class of time‐fractional diffusion equation. The time‐fractional derivative is described in the Caputo form. The L1 scheme is used for discretization of Caputo fractional derivative and a collocation approach based on sextic B‐spline basis function is employed for discretization of space variable. The unconditional stability of the fully‐discrete scheme is analyzed. Two numerical examples are considered to demonstrate the accuracy and applicability of our scheme. The proposed scheme is shown to be sixth order accuracy with respect to space variable and (2 − α)‐th order accuracy with respect to time variable, where α is the order of temporal fractional derivative. The numerical results obtained are compared with other existing numerical methods to justify the advantage of present method. The CPU time for the proposed scheme is provided. [ABSTRACT FROM AUTHOR]

In this work, a fast numerical scheme is proposed for numerical solution of a general class of nonlinear singular boundary value problems (SBVPs), which describe various physical phenomena in applied science and engineering. It is worth noting that the standard cubic B-spline collocation method provides a second order convergent approximation to the solution of a second-order SBVP, while the proposed method provides a sixth-order convergent approximation. To demonstrate the applicability and accuracy of the method, we consider six nonlinear examples, including five real-life problems. It is shown that the experimental rate of convergence of present scheme is six and our method produces significantly more accurate results than the existing ones. Additionally, the CPU time for the method is provided. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is a global prevalent ailment that causes lives in a predominant number. CKD is the 11th most deadly cause of global mortality with 1.2 million death each year and according to kidney Foundation of Bangladesh, around 40,000 CKD people experienced kidney failure annually as well as several thousand passed away in short stage of life because of CKD. Predictive analytics for healthcare using machine learning is a challenged task to help doctors decide the exact treatments for saving lives. Scientist researched collaboratively chronic kidney diseases, with the majority of their work on pure statistical models, generating numerous gaps in the development of machinelearning models. In this work we discussed the current methods and suggested improved technology based on the Correlation, which combined significant characteristics of the F scores and evaluated two pre-processing scenarios. In addition, we provided machine training methods for anticipating chronic renal disease with clinical information. Two techniques of master teaching are explored like Random Forest Classifier (RFC) and Logistic Regression (LR). The components are made from UCI dataset of chronic kidney disease and the results of these models are compared to determine the best regression model for the prediction. From this two preprocessing cases, replacing missing values with mean values of each column and choosing important features was most logical as it allows to train with more data without dropping. However, correlation gave the best outcomes in both two cases where it obtained 98% accuracy. Thus, the system can be implemented for early stage CKD prediction in a cost efficient way which will be helpful for under developed and developing countries. [ABSTRACT FROM AUTHOR]

This paper is concerned with the development of a high order numerical technique for solving time‐fractional reaction–diffusion equation. The fractional derivative in the governing equation is described in the Caputo sense and a collocation method based on quintic B‐spline basis function is used to discretize the space variable. The stability and convergence analysis of the method are investigated, and it is shown that the proposed method converges to the exact solution of the problem with order of convergence O(Δt2 − α + Δx4), where α is the order of fractional derivative (0 < α < 1). Three test problems are considered to illustrate the efficiency and accuracy of present numerical scheme and to verify the theoretical result. It is shown that the order of fractional derivative has a profound effect on the solution of time‐fractional reaction–diffusion equation. [ABSTRACT FROM AUTHOR]

In this paper, we describe an optimal B-spline collocation method to solve one-dimensional non-linear Bratu problem. Convergence result of the method is established through Green's function technique and it is proved that the method has sixth order convergence. The applicability and accuracy of the method are demonstrated through two numerical examples. It is shown that the computational result is consistent with theoretical prediction. Moreover, the numerical results obtained by the present method are compared with those obtained by two other B-spline collocation approaches reported in the literature. The computed results reveal that our method is accurate and easy to implement. [ABSTRACT FROM AUTHOR]

Carnosic acid is a benzenediol abietane diterpene having antioxidant and other medicinal activities. The medicinally active compound carnosic acid was isolated from leaves of the herb Rosmarinus officinalis. A simple solid-liquid extraction with solvent acetone in Soxhlet extractor was used for the extraction of compound from the plant source. The purity of the compound was studied using thin layer chromatography (TLC) and liquid chromatography-mass spectroscopy (LCMS) studies and the results were compared with standard carnosic acid. The result proves that the isolated compound was found to have 98.10% purity and no other impurities were observed. The molecular structure of the isolated compound was derived using spectral studies like UV, IR, NMR, C13 and mass spectroscopy. The spectral study proves that the compound has a molecular structure of 332 g/mol and molecular formula of C20H28O4. The molecular mass, formula and the molecular structure of the isolated compound was found to be similar to that of standard carnosic acid. [ABSTRACT FROM AUTHOR]

Mental disorders are highly prevalent and have been associated with considerable suffering and impacts on emotional and physical health, functioning, and costs. Worldwide, epidemiological surveys have estimated rates of lifetime prevalence of mental disorders among adults and children ranging from 12.2 to 48.6%, and 12-month prevalence rates ranging from 8.4 to 29.1%. Recognizing barriers and their individual contributions to delaying or preventing access to mental health services is a key step to overcome obstacles. To assess barriers to access psychiatric care in children and adolescents with first episode psychosis. This study is cross sectional, hospital based, single contact, time bound study from June to December, 2012. Purposive sampling technique is used to select the samples of the study. This study is conducted at Out-Patient Department of Centre for Child and Adolescent Psychiatry (CCAP) of Central Institute of Psychiatry (CIP), Kanke, Ranchi. Respondents of present study were the primary caregivers of the patient. The tools were assessed on Socio Demographic and Clinical Data Sheet and the Barriers to Access to Care Evaluation (BACE) scale was developed in the Health Services and Population Research Department of the Institute of Psychiatry, King's College, in London. The present study findings indicates that children and adolescents with first episode psychosis had moderate level of barriers having to access psychiatric care, children and adolescents had experienced more instrumental barriers, the reasons why people with mental ill health sometimes avoid or delay seeking help from health services are numerous and include instrumental barriers. Present study findings indicate that early recognition and treatment is crucial to improve illness course and prognosis and to reduce treatment complexity and costs for children and adolescents with first episode psychosis. Barriers to access, children and adolescents, first episode & psychiatric care. [ABSTRACT FROM AUTHOR]

Abstract: Solid state Stellite6 coatings were deposited on steel substrate by friction surfacing and compared with Stellite6 cast rod and coatings deposited by gas tungsten arc and plasma transferred arc welding processes. Friction surfaced coatings exhibited finer and uniformly distributed carbides and were characterized by the absence of solidification structure and compositional homogeneity compared to cast rod, gas tungsten arc and plasma transferred coatings. Friction surfaced coating showed relatively higher hardness. X-ray diffraction of samples showed only face centered cubic Co peaks while cold worked coating showed hexagonally close packed Co also. [Copyright &y& Elsevier]

Abstract: Two pass and three pass bead-over-bead (BoB) electron beam weld technique was attempted on Ti6Al4V to improve its Charpy impact and fracture toughness of weld metal portion. Hardness and microstructural studies were also done to support the findings. The hardness values of the weld metals were found to be higher than their base metal counterpart. The weld metal hardness came down when deposited with bead-over-bead technique. Conventional stringer bead welding caused reduction in Charpy impact toughness compared to its base metal counterpart. Bead-over-bead technique improved the notch toughness of weld metals. The fracture toughness values of the weld metals were found to be superior to that of base metal. This is in contrast to the Charpy impact toughness values where the impact toughness of base metal was better than the stringer and bead-over-bead weld metals. The better fracture toughness of weld metals was related to the basket-weave structure compared to the equi-axed structure of base metal. Bead-over-bead technique was found to help in improving the fracture toughness of weld metal further. Overall, the study showed that the bead-over-bead technique improved both notch toughness and fracture toughness of Ti6Al4V electron beam weld metals. [Copyright &y& Elsevier]

Six linear chain coordination polymers containing alternating Ce IVand Zn II/Cd IIcoordination polyhedra are formed with dipicolinic acid (dipicH 2) depending upon the crystallization conditions. They belong to three isomeric types that differ in the way the tricapped trigonal prismatic polyhedra of [Ce(dpic) 3] 2−are linked with the Zn/Cd octahedra. The different isomers differ in complexity as reflected in their angularity and repeat units. Highly angular chains lead to porous structures, one of which incorporates a 16-water cluster. [ABSTRACT FROM AUTHOR]

Single-phase nanocrystalline powder of barium zirconium titanate, Ba(Zr x Ti1−x )O3 (BZT), x =0.10, 0.20 and 0.30, was synthesized at low-temperature using an aqueous co-precipitation technique. X-ray diffraction (XRD) of the as-precipitated powder showed single-phase BZT formation. The decrease in precipitant concentration resulted in impurity barium carbonate phase formation. Transmission electron microscopy studies of as-prepared powders showed an average particle size of 30nm and the crystallite size from XRD was estimated to be 13nm. The microstructural studies of sintered bodies showed an average grain size of 4μm and the dielectric and ferroelectric behaviour of BZT with 10mol.% Zr is reported. [Copyright &y& Elsevier]

Summary: Understanding the effect of chemical reactions on the hydrologic properties of sub-surface media is critical to many natural and engineered sub-surface systems. Methods and information for such characterization of fractured media are severely lacking. Influence of glass corrosion (precipitation and dissolution) reactions on fractured glass blocks HAN28 and LAWBP1, two candidate waste glass forms for a proposed immobilized low-activity waste (ILAW) disposal facility at the Hanford, WA site, was investigated. Flow and tracer transport experiments were conducted in such randomly and multiply fractured ILAW glass blocks, before and after subjecting them to corrosion using vapor hydration testing (VHT) at 200°C temperature and 200psig (1379KPa) pressure, causing the precipitation of alteration products. A tri-axial fractured media flow and transport experimental apparatus, which allows the simultaneous measurement of flow and transport properties and their anisotropy, has been designed and built for this purpose. Such apparatus for fractured media characterization are being reported in the literature only recently. Hydraulic properties of fractured blocks were measured in different orientations and along different cardinal directions, before and after glass corrosion reactions. Miscible displacement experiments using a non-reactive dye were also conducted, before and after glass corrosion reactions, to study the tracer transport behavior through such media. Initial efforts to analyze breakthrough curve (BTC) data using a 1D advection dispersion equation (ADE) solution revealed that a different fractured media transport model, which accurately accounts for the heterogeneous transport behavior in 3D, may be necessary for such interpretation. It was found that glass reactions could have a significant influence on the hydrologic properties of fractured ILAW glass media. The methods and results are useful to better understand the effect of chemical reactions on the hydrologic properties of fractured geomedia in general and glass media in particular. [Copyright &y& Elsevier]

The crystal structure of Ce(dipic)2(H2O)3·4H2O reveals an unusual hydrogen-bonded water octamer. The centrosymmetric octamer is built by bridging two water molecules to the chair form of a water hexamer. The structure, predicted to be unstable relative to other octameric structures, is stabilized by hydrogen bonding with the carboxylate groups lining the cavity in the host crystal. The water cluster is removed by heating at 100 °C but can be reassembled by exposing the dehydrated form to an atmosphere saturated with water vapor. [ABSTRACT FROM AUTHOR]

The addition of copper increases the strength of aluminium, but decreases the localised corrosion resistance of the metal to seawater as the copper containing intermetallics exhibit different electrochemical properties from the matrix. The main requirement of corrosion resistance could be met through the surface modification by removing the copper rich phase. The present work involves investigations of the influence of prior copper removal treatment on the pitting and general corrosion resistance of AA2219 alloy containing a high copper content in different initial thermal tempers. Significant improvement in the pitting and general corrosion resistance after surface copper removal treatment was evident from the results of electrochemical polarisation and the impedance tests. Attempts were also was made to modify the surface further, with a conversion layer of cerium as an alternative to the chromate coating. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of partially melted zones and heat affected zones of gas tungsten arc (GTA) welds in AA2219 and AA6061 alloys with different initial thermal tempers has been studied. Continuous and pulsed current GTA welding techniques were used. Potentiodynamic polarisation testing was carried out to determine the corrosion resistance. Optical and scanning electron microscopy studies were carried out to determine the corrosion mechanism. The partially melted zone of the welds was found to be attacked severely. A pulsing technique was found to decrease the severity of corrosion damage in the partially melted zone. The prior thermal temper of the alloys was found to influence the corrosion of heat affected zones of welds. [ABSTRACT FROM AUTHOR]

Cu—Al2O3 nanocomposite is successfully synthesized by reactive milling of CuO/Cu2O and Al. Wet milling in toluene transforms the combustion reaction to a progressive reaction. The extent of reduction reaction increases with increase in excess reductant (Al). The crystallite size of Cu obtained from reactive milling is much finer than that obtained from ball milling of Cu and Al2O3. [Copyright &y& Elsevier]

Presents an interfacial area ratio (IAR) model for the prediction of diffusion coefficients as a function of the degree of water saturation. Definition of tortuosity factor in the IAR model; Factor that affects diffusion behavior in unsaturated media; Diffusion coefficients for conservative solutes as a function of water content.

AbstractThe harmful by-product of paracetamol is known as N-Acetyl-p-benzoquinoneimine, (NAPQI). When paracetamol is given at therapeutic dosages or in excess, it undergoes Phase I metabolism in the liver via Cytochrome P-450 2E1 (CYP2E1), and then it produces NAPQI. Previous studies reported that a nonionic surfactant known as Brij 35 (Polyoxyethylene lauryl ether) has been shown to be an effective inhibitor of CYP2E1 and P-glycoprotein (P-gp). Hence, this in vitro and in vivo investigation set out to assess Brij 35 impact on paracetamol CYP2E1-mediated metabolism. For the in vitro investigation, isolated rat hepatocytes were used. Male Wistar rats were used for in vivo studies. There were 30 rats in total, with six individuals each group distributed among the five groups. The first group animals received 0.5% sodium carboxy methyl cellulose (control group); the second group animals treated with 300 mg/kg of paracetamol; the third group animals treated with Brij 35 (5 mg/kg) along with 300 mg/kg of paracetamol; the fourth group animals treated with 10 mg/kg of Brij 35 along with 300 mg/kg of paracetamol, and the fifth group animals treated with 20 mg/kg of Brij 35 along with 300 mg/kg of paracetamol for consecutive 21 days. The current study found that paracetamol plasma concentrations were much higher and NAPQI plasma concentrations were much lower when Brij 35 was co-administered may be due to inhibition of CYP2E1-mediated metabolism and P-gp-mediated intestinal transport of paracetamol. Brij 35 also reduced the increased hepatic and renal markers with significant hepatoprotective and nephroprotective changes in the histopathological investigation. [ABSTRACT FROM AUTHOR]

Presents information pertaining to the nonaqueous phase liquids (NAPLs). Identification of empirical indices; How can the presented methods and results were used; Availability of methods.

Describes an experimental method to measure specific fluid-fluid interfacial areas of immiscible fluids in porous media. Environmental hydrology; Morphology of immiscible fluids; Photoluminescent imaging technique; Interfacial tension measurement.

Use of different seed priming treatments improves seed germination and thus increases plant growth and yield potential. Eco-friendly, cost-effective, simple, and effective seed treatments need to be developed for a high-consuming crop like chickpea (Cice rarietinum Lin.). In the present study, manganese oxide nanoparticles were synthesized using an aqueous extract of roots of Kigelia africana (lam.) Benth and used as nano priming agents for chickpea seeds. The synthesized nanoparticles were found to have rod-like morphology with heterogeneous size distribution. The nanoparticle's average size was found to be 67 nm with a metal content of 52.04 %. The sprout's emergence was found to be high in nanometal-treated chickpea seeds than in untreated and metal treated seeds. The seedling rate after ten days of sowing was found to be high in nanoparticle-treated seeds. The nanometal treatment shows low mean germination time, high germination rate, root length and shoot length of the chickpea compared to untreated samples. The present study results demonstrates that seed priming with manganese oxide nanoparticles could enhance seed germination and growth through an eco-friendly and sustainable nanotechnological approach. [ABSTRACT FROM AUTHOR]

This paper is concerned with the development of a collocation method based on the Bessel polynomials for numerical solution of a general class of nonlinear singular boundary value problems (SBVPs). Due to the existence of singularity at the point x = 0 , we first modify the problem at the singular point. The proposed method is then developed for solving the resulting regular boundary value problem. To demonstrate the effectiveness and accuracy of the method, we apply it on several numerical examples. The numerical results obtained confirm that the present method has an advantage in terms of numerical accuracy over the uniform mesh cubic B-spline collocation (UCS) method (Roul and Goura in Appl Math Comput 341:428–450, 2019), non-standard finite difference (NSFD) method (Verma and Kayenat in J Math Chem 56:1667–1706, 2018), three-point finite difference methods (FDMs) (Pandey and Singh in Int J Comput Math 80:1323–1331, 2003; Pandey and Singh in J Comput Appl Math 205:469–478, 2007) and the cubic B-spline collocation (CBSC) method (Caglar et al. in Chaos Solitons Fractals 39:1232–1237, 2009) [ABSTRACT FROM AUTHOR]

The present study was investigate possible mechanism of action of anti cataract activity of fractions isolated from Albizia procera stem bark chloroform extract against glucose induced cataract lenses. Goat eye lenses were divided into nine groups. Group I lenses were incubated in artificial aqueous humor with glucose concentration 5.5 mM (normal control). Group II lenses were incubated with glucose concentration 55 mM (toxic control), remain groups were incubated with glucose concentration 55 mM along with isolated fractions (4mg/ml). After 72 hrs of incubation, lens was subjected to photographic evaluation for opacity, lens homozenate supernatant used for estimation of total proteins, glutathione and Na + K+ ATPase activity. After 72 h of incubation in glucose 55 mM, lens becomes completely opaque as against lenses incubated in 5.5 mM glucose. Incubated lenses with isolated fractions C of Albizia procera stem bark chloroform extract at concentration 4 mg/ml, seems to greater retard the progression of lens opacification, increase total protein (P<0.05) and glutathione (P<0.05) and balanced Na+ and K+ levels by improving Na+ K+ ATPase activity (P<0.05) in cataract lens compare to other fractions treated lenses. It was concluded that fraction C of Albizia procera stem bark chloroform extract possesses anti cataract potential due to their anti oxidant activity and improving Na+ K+ ATPase activity. [ABSTRACT FROM AUTHOR]

Lipozyme® TL IM immobilized on silica catalyses the deacylation of 4-C-acyloxymethyl-3,5-di-O-acyl-1,2-O-(1-methylethylidene)-β-l-threo-pentofuranose to form 3,5-di-O-acyl-4-C-hydroxymethyl-1,2-O-(1-methylethylidene)-α-d-xylo-pentofuranose in a highly selective and efficient manner. [ABSTRACT FROM AUTHOR]

Abstract: Hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) represent the main types of calcium phosphates used for bone and dental surgery. HA is thermodynamically the most stable phase in physiological conditions and has the ability for direct chemical bonding to bone while β-TCP is found to be resorbable in-vivo with new bone growth replacing the implanted β-TCP. The bioactivity and bioresorbability of the biphasic calcium phosphate (BCP) ceramics can be controlled by varying HA/β-TCP ratio. Nanostructured calcium phosphates promote osseointegration, which is critical for the clinical success of orthopedic/dental implants. The present study demonstrates the preparation of nanostructured BCP ceramics by microwave processing. Since the physiological stability is, important parameter while selecting the material for implantation, the in-vitro dissolution studies of BCPs with different HA/β-TCP ratios were carried out under the conditions of osteoclastic resorption. The results suggest the dissolution of the BCP ceramics can be fine-tuned by varying the HA/β-TCP ratios. [Copyright &y& Elsevier]

Phosphoinositol phosphatases are important regulators of signaling pathways relevant to both diabetes and cancer. A 3′-phosphoinositol phosphatase, phosphatase homologous to tensin (PTEN), is both a tumor suppressor and a negative regulator of insulin action. A 5′-phosphoinositol phosphatase, SH2-containing 5′-inositol phosphatase (SHIP2), regulates insulin signaling and its genetic knockout prevents high-fat diet-induced obesity in mice. SHIP2 also regulates cytoskeleton remodeling and receptor endocytosis. This and the fact that both PTEN and SHIP2 act on the same substrate suggest a potential role for SHIP2 in cancer. Here we report that, in direct contrast to PTEN, SHIP2 protein expression is elevated in a number of breast cancer cell lines. RNA interference-mediated silencing of SHIP2 in MDA-231 cells suppresses epidermal growth factor receptor (EGFR) levels by means of enhanced receptor degradation. Furthermore, endogenous SHIP2 in MDA-231 breast cancer cells supports in vitro cell proliferation, increases cellular sensitivity to drugs targeting the EGFR and supports cancer development and metastasis in nude mice. In addition, significantly high proportions (44%; P = 0.0001) of clinical specimens of breast cancer tissues in comparison with non-cancerous breast tissues contain elevated expression of SHIP2 protein. Taken together, our results demonstrate that SHIP2 is a clinically relevant novel anticancer target that links perturbed metabolism to cancer development. [ABSTRACT FROM AUTHOR]

Arabidopsis Flagellin sensitive2 (FLS2) is a transmembrane leucine-rich repeat receptor-like kinase, which recognizes a conserved 22 amino acid peptide (flg22) of bacterial flagellin and activates downstream defense signaling pathways resulting in enhanced resistance against plant pathogens. The underlying mechanisms for the activation of FLS2 in the cell membrane, however, are not fully understood. Using fluorescence recovery after photobleaching (FRAP), we demonstrate that approximately 75% of the FLS2 in the plasma membrane diffuses laterally with a diffusion coefficient of 0.34 μm2 s−1, indicating that it moves rapidly. Further, we show that FLS2 is less mobile in the presence of flg22, suggesting its ligand-dependent confinement to microdomains or transient interaction with other less mobile membrane proteins. Using an in vivo bimolecular fluorescence complementation (BiFC) system and fluorescence resonance energy transfer (FRET), which reveals in vivo protein–protein interactions, we show that FLS2 does not homodimerize either constitutively or in the presence of flg22. Our data suggest that the reduced mobility of FLS2 after binding flg22 and its existence in monomeric form are important mechanistic features of FLS2 early signaling. [ABSTRACT FROM AUTHOR]

This article comprehensively presents an overview of the technological advances in automated aircraft sheet metal component production technology developments due to the initiative by the Aeronautical Development Agency, Ministry of Defense, Government of India, since 1989 in collaboration with the Indian Institute of Technology, Bombay. Commencing with a modest computer-aided flat pattern development software system suitable for a class of sheet metal components, this activity after several stages of development has now resulted in the development of full-fledged, personal-computer-based graphical interactive, three-dimensional application flat pattern development and automated production loft generation system. This research, encompassing the practical methods (exclusively developed for flat pattern software), literature survey, development of key algorithms suitable for designing a system for automated loft generation for a variety of surfaces with complex geometric features characteristic of aircraft sheet metal components with the aid of a wide choice of surface model creations, and testing and validation (carried out through an associated aircraft factory, Hindustan Aeronautics Limited), is now being published through four full-length papers concluding with the present paper. In fact, comprehensive illustrations of production lofts sampled from over thousands of parts used in the factory pertinent to the Indian Light Combat Aircraft (termed as Tejas) and other projects like Advanced Light Helicopter (termed as Dhruv) sheet metal components are included here to provide insight into these developments, and also to provide a glimpse of the success of the mission of indigenous automated aircraft sheet metal component manufacture. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "High Plasma Levels of Factor VIII and the Risk of Recurrent Venous Thromboembolism," by P.A. Kyrle and colleagues, previously published in the August 17, 2000 issue of the "New England Journal of Medicine."

The present research is focused on investigating the phytochemical analysis and antioxidant activity of Aegialitis rotundifolia Roxb. leaf. Different solvent extracts of A. rotundifolia Roxb. leaves are screened for secondary metabolites by qualitative and quantitative analysis. The resultant phytochemical screening proves that the plant leaves consist of various secondary metabolites. The quantitative analysis proves that phenolic compounds and flavonoids are dominant among them. Four different antioxidant activity methods, namely, ABTS radical scavenging activity, phosphomolybdate assay, peroxide activity and FRAP (Ferric Reducing Antioxidant Power), are used for assessing the activity of the leaf extract. Ethanolic and aqueous extracts of the leaf have high potency of antioxidant activity and reported dose-dependent activity. Similar promising antioxidant results are also reported for ABTS radical scavenging activity (82.4% reduction at 200 µg mL-1 of ethanol and 90.0% reduction at 200 µg mL-1 of aqueous extract), phosphomolybdate assay (82.4% reduction at 200 µg mL-1 of ethanol and 74.5 % reduction at 200 µg mL-1 of aqueous extract) and peroxide activity (92.1 % reduction at 200 µg mL-1 of ethanol and 93.1 % reduction at 200 µg mL-1 of aqueous extract). The antioxidant activity reported with ethanol (157.4 mmol Fe2+/g) and aqueous extract (129.8 mmol Fe2+/g) was also studied by analyzing with FRAP reduction. The obtained findings confirmed the high antioxidant activity of plant leaf extract and its application for pharmacological activity. [ABSTRACT FROM AUTHOR]

The present study was investigate possible mechanism of action of anti cataract activity of fractions isolated from Albizia procera stem bark chloroform extract against glucose induced cataract lenses. Goat eye lenses were divided into nine groups. Group I lenses were incubated in artificial aqueous humor with glucose concentration 5.5 mM (normal control). Group II lenses were incubated with glucose concentration 55 mM (toxic control), remain groups were incubated with glucose concentration 55 mM along with isolated fractions (4mg/ml). After 72 hrs of incubation, lens was subjected to photographic evaluation for opacity, lens homozenate supernatant used for estimation of total proteins, glutathione and Na + K+ ATPase activity. After 72 h of incubation in glucose 55 mM, lens becomes completely opaque as against lenses incubated in 5.5 mM glucose. Incubated lenses with isolated fractions C of Albizia procera stem bark chloroform extract at concentration 4 mg/ml, seems to greater retard the progression of lens opacification, increase total protein (P<0.05) and glutathione (P<0.05) and balanced Na+ and K+ levels by improving Na+ K+ ATPase activity (P<0.05) in cataract lens compare to other fractions treated lenses. It was concluded that fraction C of Albizia procera stem bark chloroform extract possesses anti cataract potential due to their anti oxidant activity and improving Na+ K+ ATPase activity. [ABSTRACT FROM AUTHOR]

Objective: The present Study was to identify more effective hypoglycemic fractions from chloroform extract of Albizia procera stem bark. Material and methods: Isolated fractions of Albizia procera stem bark chloroform extract were given individually to different batches of rats both normal (80 mg/kg of b.wt animals) and STZ induced diabetic rats (160mg/kg b.wt animals) after an overnight fast. The blood glucose levels were measured at 0, 1, 2, 3, 5 and 6 hours after the treatment. Fractions were also treated to STZ induced diabetic rats by chronically (80mg/kg b.wt). Results: The fractions E of Albizia procera stem bark chloroform extract was shown maximum blood glucose lowering effect in both normal and STZ diabetic rats with acute and chronic treatment. The other fractions are also showing hypoglycemic and antihyperglycemic activity, but the effect is significantly less than that of fraction E. The antihyperglycemic activity of fractions of Albizia procera stem bark chloroform extract was compared with the treatment of glibenclamide. Conclusion: The present data confirm the anti diabetic activity of Albizia procera in Indian traditional medicine for Diabetes mellitus treatment. The anti hyperglycemic action attributed to the presence of valuable flavonoids, terpinoids in the fraction E. [ABSTRACT FROM AUTHOR]

Highlights: [•] Instantaneous cooling rate is maximum with the modified pulse mode and Helium shielding gas by steeper temperature gradient. [•] The maximum instantaneous cooling rate is effective in laves formation temperature range. [•] Reduction in laves phase has been demonstrated. [•] Segregation of Nb decreases with enhanced cooling rates and the phenomenon need to be further probed for Mo. [•] Reduction in laves phase and alloying element segregation has been confirmed with dendrite arm spacing. [ABSTRACT FROM AUTHOR]

Highlights: [•] Solid state coating by friction surfacing method. [•] D2 tool steel is coated over relatively softer low carbon steel. [•] Defect free interface between tool steel coating and low carbon steel substrate. [•] D2 coatings exhibited higher hardness and good wear resistance. [•] Highly refined martensitic microstructure in the coating. [ABSTRACT FROM AUTHOR]

Abstract: The present work deals with the effects of pre- and post-weld heat treatments on microstructure and mechanical properties of alloy 718 friction weld joints. Prior to friction welding, alloy 718 rods were subjected to two types of heat treatments - solution treatment (ST) and solution treatment followed by aging (STA). In the as-welded condition, samples welded with prior ST condition exhibited higher hardness in the weld zone compared to the base material in ST condition and this is attributed to grain refinement due to dynamic recrystallization. Samples welded with prior STA condition exhibited decreased hardness in the weld zone and room temperature tensile properties in relation to the base material in STA condition. It is due to dissolution of γ″ (Ni3Nb) phase as the temperature measured at weld zone was found to be 1118°C. In order to retrieve the hardness and room temperature tensile properties, friction weld joints were subjected to direct aging (DA) treatment. A significant increase in hardness was observed in the weld zone after direct aging for both samples welded in ST and STA conditions. This is attributed to the grain refinement due to dynamic recrystallization and formation of precipitates by the DA treatment. [Copyright &y& Elsevier]

New blue- to yellow-emitting materials have been developed by incorporating fluorene-based chromophores on pyrene core with acetylene linkage and using multifold palladium-catalyzed cross-coupling reactions. Both mono- and tetrasubstituted derivatives have been synthesized and characterized. The tetrasubstituted derivatives displayed red-shifted emission when compared to the monosubstituted derivative indicative of an extended conjugation in the former. End-capping with a diphenylamine unit further red-shifted the absorption and emission profiles and imparted a weak dipolar character to the molecules. Amine-containing derivatives displayed positive solvatochromism in the fluorescence spectra indicating a more polar excited state due to an efficient charge migration from the diphenylamine donor to the pyrene π-acceptor. All of the derivatives were tested as emitting dopants with host material 4,4'-bis(9H-carbazol-9-yl)biphenyl (CBP) in a multilayered OLED and found to exhibit bright blue or yellow electroluminescence. The device utilizing 1,3,6,8-tetrasubstituted pyrene derivative as a dopant emitter displayed highest maximum luminescence 4630 cd/m² with power efficiency 3.8 lm/W and current efficiency 7.1 cd/A at 100 cd/m² attributable to the proper alignment of energy levels that led to the efficient harvesting of excitons. All of the devices exhibited color purity over a wide range of operating voltages. [ABSTRACT FROM AUTHOR]

Synthetic hydroxyapatite (HA) has been extensively used as an implant material owing to its excellent osteoconductive properties. The preparation of nanocrystalline HA is of paramount importance as the large surface area of the diminutive crystals makes them very active and consequently strongly affects the properties of it. In this paper, to study the effect of microwave irradiation power and time, nanocrystalline HA was synthesised at different microwave irradiation times (15, 45, 120, 240 and 600 min) and with different microwave powers (800 and 1100 W). This study also investigated the crystallisation of HA in the presence of sodium alginate and alginic acid at different addition levels (5, 10 and 15 wt-% to the final HA). It was found that crystallinity of the HA increases with increasing microwave irradiation time and/or power. Sodium alginate or alginic acid addition during crystallisation of HA decreases the crystal size and crystallinity of the precipitated HA. [ABSTRACT FROM AUTHOR]

Abstract: Fusion zone of AA2219 alloy gas tungsten arc welds was subjected to compressive deformation by rolling the crown of the weld in the welding direction. Twelve percent compressive deformation improved the as-weld hardness from 75 to 100 VHN. The yield strength increased from 125 to 220MPa. The welds made by pulsed current technique exhibited better strength and ductility compared to their continuous current weld counterparts, both in the as-welded condition and the deformed condition. The improvement in strength was found to be due to dislocation loops formed near the grain boundaries in the fusion zone. Direct aging of fusion zone at 190°C, increased the yield strength significantly from 125 to about 200MPa. Aging of the deformed fusion zone did not improve tensile strength further. [Copyright &y& Elsevier]

Abstract: Multipass friction stir processing of AA 2219-T87 aluminium alloy to a depth of 2 mm in a 5 mm plate resulted in fine α-Al grains, reduction and dissolution of both eutectic phase (CuAl2) and the strengthening precipitates (CuAl2). Anodic polarization and electrochemical impedance tests in 3.5% NaCl showed an improved corrosion resistance of the processed alloy, which increased with the number of passes. Salt spray and immersion tests also showed improved resistance to corrosion. The increased resistance to corrosion is attributed to the dissolution of CuAl2 particles, which was established by XRD and DSC studies. [Copyright &y& Elsevier]

Abstract: In the current investigation, nickel-base hardfacing alloy AWS NiCr-B was deposited on austenitic stainless steel substrate 316 LN using the plasma transferred arc-welding process. The deposit was characterized by hardness measurements, microstructural examination and sliding wear assessment. Identification of precipitates was carried out using X-ray diffraction, scanning electron microscope/energy dispersive X-ray analysis (SEM/EDAX), electron probe micro analyzer (EPMA) mappings and line-scan profiles. The microstructure of the hardfacing deposit predominantly consists of the γ-Ni phase and the interdendritic eutectic mixture comprised of γ-nickel and nickel-rich borides. These studies also revealed the presence of chromium-rich carbides and borides in a γ-nickel matrix. The sliding wear behaviour of the hardfacing alloy was investigated in air at three different temperatures viz., room temperature, 300 and 500°C. The study revealed significant weight loss at room temperature and abrupt decrease at high temperatures. This behaviour at high temperatures has been attributed to the formation of a wear protective oxide layer at the surface during sliding. To evaluate the microstructural stability of the deposit, ageing studies were carried out at 650°C for 250h. Microstructural examination and hardness testing revealed that there is no deterioration in the microstructure and that the hardness remains intact. Sliding wear tests at room temperature and at high temperatures also demonstrated that there is no significant change in the weight loss or the wear behaviour after the thermal exposure. [Copyright &y& Elsevier]

Abstract: Galling is a severe form of wear characterized by localized, macroscopic material transfer or removal of material when two solid surfaces experience relative sliding under load. The current paper describes the development of a wear testing machine capable of testing both galling resistance and sliding wear behaviour (pin-on-disc) at high stress levels. For evaluating galling resistance using this equipment, a stationary button is placed in contact with a rotating flat block at a desired pressure by means of a hydraulic system. The block is rotated through one revolution and both the specimens are inspected for the presence of galling as per ASTM G98-91 galling procedure. In this, button axis coincides with the rotating block axis. Surface damage as a result of galling is also evaluated by applying the desired load to the button specimen and rotating the block about its vertical axis, back and forth 10 times through 120° in 90s. To evaluate sliding wear behaviour, button axis is offset to a required distance and it is used as pin-on-disc apparatus. The apparatus developed in this work could be successfully used for assessing the sliding wear behaviour, as also the galling resistance. Various features of this apparatus and results from the tests are discussed in this paper. [Copyright &y& Elsevier]

Synthetic hydroxyapatite, (Ca10 (PO4)6(OH)2, HA), is an important material used for orthopedic and dental implant applications. The biological hydroxyapatite in the human bone and tooth is of nanosize and differs in composition from the stoichiometric HA by the presence of other ions such as carbonate, magnesium, fluoride, etc. Osseointegration is enhanced by using nanocrystalline HA. This stimulates the interest in synthesizing nanocrystalline HA by different routes and among the methods, microwave processing seems to form the fine grain size and uniform characteristic nanocrystalline materials. Fluorinated hydroxyapatite, (FHA, Ca10(PO4)6(OH)2-xFx), possesses higher corrosion resistance in biofluids than pure HA and reduces the risk of dental caries. The present work deals with the synthesis of nanocrystalline FHAs by microwave processing. The crystal size and morphology of the nanopowders were examined by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) methods. The functional groups present in FHA powders were ascertained by Fourier transform infrared spectroscopy (FT-IR) and laser Raman spectroscopy. Since the physiological stability is an important parameter while selecting the material for implantation, the in vitro dissolution studies of FHAs with different fluorine contents were carried out. [ABSTRACT FROM AUTHOR]

Solid state transition joints made, by cold extrusion, between steel and Cu powder metallurgical (P/M) preform tubes were heat treated at various temperatures and time, with and without interlayer, to evaluate the weld strength and microstructural characteristics. Post-joining heat treatments lead to different recrystallized structures near the interface due to strain localization and solute drag effect. The strain localization and residual porosity in the joints enhanced void formation in the diffusion zone when the interlayer was absent. Coarse Ni powder as an interlayer reduced the weld strength due to physical discontinuities and residual particles at the interface, after heat treatment. On the other hand, finer Ni powder improved the weld strength. Use of 1 μm Ni interlayer in combination with optimal heat treatment conditions (950°C for 2 h) resulted in about 45% increase in weld strength. [ABSTRACT FROM AUTHOR]

Abstract: The present article reports the results of preliminary studies, carried out for the first time, related to the production of bimetallic tubes by tailoring the initial materials characteristics through powder metallurgy (P/M) and cold extrusion route. It is shown that the domination of consolidation (volume change) during simultaneous deformation of P/M preforms reduces the differential velocity between the core and the sleeve as indicated by lower failure propensity of extrudes. High interfacial friction at the dissimilar P/M preform interface and in turn the high interfacial bond aids the sound flow over a wide range of processing conditions. In addition, the non-uniformities of deformation would be accommodated by the softer preform near the interface through micro-mechanical interactions. It is believed that the current approach of producing the bimetals greatly enhances the manufacturing flexibility and reduces the tool cost. [Copyright &y& Elsevier]

Bead on plate, full penetration electron beam welds were produced in 2 mm thickness sheets of Inconel 718 in the solution treated condition. Welds were subjected to an aging treatment with and without post-weld solution treatment. Weld microstructures, high temperature tensile properties and stress rupture properties were evaluated. The as welded fusion zone showed a considerable amount of interdendritic niobium segregation and brittle intermetallic Laves phase. The tensile and stress rupture properties of the welds after post-weld aging treatment were found to be inferior in relation to the base metal. Post-weld solution treatment at 980°C was found to result in partial dissolution of Laves phase, some reduction in niobium segregation and the formation of δ phase needles around the Laves particles. The use of 980°C solution treatment was found to improve the weld properties to some extent, although not to the level of the base metal. The reasons for this behaviour are discussed, correlating microstructures, fracture features and mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract: Partially melted zone (PMZ) of aluminium alloy welds is an important region and requires careful attention. This is mainly because PMZ in these materials is weak link in the weldments and is significantly affected by welding parameters. Microstructure changes in PMZ are related not only to welding heat input and techniques, but also depend on the initial thermal history of alloy (for example, whether it is in T6 or T87 condition etc.). Interestingly, not many detailed studies were available in this respect. In the present work, effect of prior thermal temper and welding techniques mainly continuous and pulsed current gas tungsten arc welding (GTAW) on the PMZ behaviour of AA2219 alloy was studied. Susceptibility to liquation was found to be high in T6 temper of AA2219 alloy than in T87. Pulsed current technique was found to improve the resistance to the susceptibility to liquation in PMZ. [Copyright &y& Elsevier]

This article reports that weld fusion zones in Inconel 718 are known to exhibit poor mechanical properties in relation to the base metal as a result of extensive interdendritic Nb segregation and consequent formation of Nb-rich, brittle, intermetallic Laves phase during weld metal solidification, which depletes the matrix of useful alloying elements and aids in easy crack initiation and propagation. Post-weld solution treatments cannot be entirely relied upon in dealing with the Laves problem as dissolution of Laves phase to any significant extent is not possible without simultaneously causing undesirable grain coarsening in the base metal. Therefore, there is a need to control Nb segregation and Laves formation during welding itself.