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In this study, we have synthesized a new family of bioactive glass (BAG) comprising of SiO 2 , Na 2 O, CaO, K 2 O, P 2 O 5 and MgO via sol-gel route. The composition of these oxides has been selected in such a way that the BAG has a coefficient of thermal expansion close to the 316L stainless steel (SS). In vitro test by soaking the BAG in simulated body fluid (SBF) showed good bioactivity due to ion exchange between alkali ions from the BAG and the ions present in the SBF. The 316L SS substrates were textured using laser before application of BAG using sol-gel dip coating. Pull off test showed that the adhesion strength in case of textured and non-textured surfaces were 4.2 MPa and 2.46 MPa, respectively. This implies that texturing of the surface is helpful in increasing the adhesion strength of the coating. The bioactive glass-coated textured surface of 316L SS substrate showed better corrosion resistance in SBF than the bare substrate for which the respective corrosion current densities were 35 nA/cm2 and 353 nA/cm2, thereby indicating that the single layer sol-gel dip coating of bioactive glass improved the corrosion resistance of the 316L SS implants. The analysis of scanning electron microscopy (SEM) images of the coating after immersion in SBF shows the formation and growth of the apatite layer that will further inhibit the corrosion of the substrate. These results demonstrate the potential of the synthesized BAG as a coating material for 316L SS implants. [ABSTRACT FROM AUTHOR]

This paper puts forward the comparative performances for synchronisation between (i) systems from different chaotic system families, (ii) systems from the Unified Chaotic System (UCS) family, (iii) a hyperchaotic and a chaotic systems and (iv) identical chaotic systems. Three different well-known control techniques, i.e. Nonlinear Active Control (NAC), Sliding Mode Control (SMC) and Adaptive Control (AC) are used for synchronisation between various pairs of chaotic and/or hyperchaotic systems. Performances of NAC, SMC and AC techniques are investigated and compared with synchronisation of different pairs of chaotic systems based on the error dynamics and required control inputs. The integral square error and required control energy measures are considered for comparison. Finally, a generalised view on the use of the control techniques for synchronisation is finally proposed. Moreover, a new chaotic system is proposed and its qualitative analysis is done to illustrate the chaotic behaviour of the system. The new system is used as an example of synchronisation. MATLAB simulation results are presented which reflect the successful achievement of the objectives. [ABSTRACT FROM AUTHOR]

Background Several observational studies have shown that statins may modify the risk of gastric cancer (GC). We carried out a systematic review and meta-analysis of studies evaluating the effect of statins on GC risk. Patients and methods We conducted a systematic search of multiple databases up to December 2012. Studies that evaluated exposure to statins, reported GC outcomes and odds ratio (OR) or provided data for their estimation were included in the meta-analysis. Pooled OR estimates with 95% confidence intervals (CIs) were calculated using the random-effects model. Results Eleven studies (eight observational, three post-hoc analyses of 26 clinical trials) reporting 5581 cases of GC were included. Meta-analysis showed a significant 32% reduction in GC risk with statin use (adjusted OR, 0.68; 95% CI, 0.51–0.91). After exclusion of one study which was contributing to considerable heterogeneity, a significant 16% reduction in GC risk was a more conservative, consistent estimate (adjusted OR, 0.84; 95% CI, 0.78–0.90). This chemopreventive association was present in both Asian (adjusted OR, 0.68; 95% CI, 0.53–0.87) and Western population (adjusted OR, 0.86; 95% CI, 0.79–0.93). Conclusions Meta-analysis of studies supports a protective association between statin use and GC risk, in both Asian and Western population, in a dose-dependent manner. [ABSTRACT FROM PUBLISHER]

Abstract: Several small Mn–Fe oxide and Mn-oxide ore bodies associated with Precambrian Iron Ore Group of rocks are located within Koira-Noamundi province of north Orissa, India. These deposits are classified into in situ (stratiform), remobilized (stratabound) and reworked categories based on their field disposition. Volcaniclastic/terrigenous shale in large geographic extension is associated with these ore bodies. The in situ ore bodies are characterised by cryptomelane-, romanechite- and hematite-dominating minerals, low Mn/Fe ratio (1.1) and relatively lower abundance of trace (1500–2500ppm) constituents. In such type of deposits the stratigraphic conformity of oxides with the tuffaceous shale suggests precipitation of Mn and Fe at a time of decreased volcaniclastic/terrigenous contribution. The minor and trace elements were removed from solution by adsorption rather than by precipitation. Both Mn and Fe oxides when precipitated adsorb trace elements strongly but the partitioning of elements takes place during diagenesis. The inter-elemental relationship reveals that Cu, Co, Ni, Pb and Zn were adsorbed on precipitating hydrous Mn oxides and form manganates. Some of these elements probably get desorbed from Fe oxide because of their inability to substitute for Fe3+ in the lattice of its oxide. However, P, V, As and Mo were less partitioned and retained in Fe-oxide phase. Positive correlation between Al2O3 and SiO2, MgO, Na2O, TiO2 and some traces like Li, Nb, Sc, Y, Zr, Th and U points to their contribution through volcaniclastic/terrigenous detritus of both mafic and acidic composition. The remobilized ore bodies are developed in a later stage through dissolution, remobilization and reprecipitation of Mn oxides in favorable structural weak planes under supergene environment. Increase in average Mn/Fe ratio (8) and trace content (5000–8500ppm) by 5–2.5 orders of magnitude, respectively, or more above its abundance in adjoining/underlying protore is characteristic of these deposits. The newly formed Mn ores constituting lithiophorite, cryptomelane/romanechite and goethite get quantitatively enriched in traces like Cu, Co, Ni, Pb and Zn. Positive correlation between Mn, Li, Co and Zn is due to the formation of mineral of lithiophorite–chalcophanite group during redistribution and reconcentration of Mn oxide. P and V, which were present in Fe oxide, also get dissolved and reprecipitate with Fe oxyhydroxide in these ores. Some other elements like Y, Th and U show positive relation with Fe. This is probably due to leaching of these elements during chemical weathering of associated shale and getting re-adsorbed in Fe-oxyhydroxide phase. However, under oxidizing environment selective cations like Ba, K, etc. resorb from Mn-structure, resulting in the development of pyrolusite (Mn/Fe>20). In such transformation, trace metals from pyrolusitic structure expels out, resulting thereby in a considerable reduction in total trace value (<3000ppm). The reworked ore bodies are allochthonous in nature and developed through a number of stages during terrain evolution and lateritisation. Secondary processes such as reworking of pre-existing crust; solution and remobilization; precipitation and cementation and transport, etc. are responsible for their development. Such deposits are usually very low in Mn/Fe ratio (3) and trace content (<2000ppm). [Copyright &y& Elsevier]

Abstract: This study was conducted to evaluate the effects of intercropping Sesbania with dry-seeded rice up to its vegetative phase (Sesbania), mulching with wheat residue (mulch) and herbicides for managing weeds and optimising the yield of dry-seeded rice. The density of grass weeds was lower with the mulch at all stages of crop growth. Though the dry weight of grass weeds at 30 days after seeding (DAS) was lower with Sesbania than with mulch, they were similar at later stages. A lower broadleaved weed density and dry weight were observed with Sesbania than with the mulch. It is concluded that application of wheat residue mulch at 4tha–1 and Sesbania intercropping for 30 days were equally effective in controlling weeds associated with dry-seeded rice. However, pendimethalin (1000ga.i.ha–1) or pretilachlor with safener (500ga.i.ha–1) as pre-emergence applications followed by one hand-weeding were effective in controlling weeds, increasing grain yield of dry-seeded rice, and resulting in higher net returns than the weed-free treatment. [Copyright &y& Elsevier]

Abstract: Increased hematopoiesis, driven by colony-stimulating factors (CSFs), is known to occur in infectious diseases. However, whether Leishmania donovani component(s) can directly induce the synthesis and secretion of CSFs is not known. We report that L. donovani amastigote antigens soluble in culture medium (LDAA; 0.01–10 mg/kg), injected intravenously in BALB/c mice, induced the production of serum CSFs; maximum induction (128>16 colonies) occurred at 1 mg/kg. In vitro also, LDAA (0.01–1 mg/ml) induced mouse peritoneal macrophages (MØs) to elaborate CSFs in the conditioned medium (CM); 0.1 mg/ml LDAA appeared optimal (68±9 colonies). Both in vivo and in vitro, the kinetics of CSF production were similar with peak response occurring 24 h after stimulation and return to background levels by 72 h. A predominant ∼12 kDa LDAA protein (LDAA-12) also induced CSF production, both in serum and CM, in a dose-and time-dependent manner. Rabbit anti-LDAA-12 antibody significantly (p&#60;0.05) reduced both the LDAA-and LDAA-12-induced CSF production, in vitro. Functionally, the LDAA-12-induced CSFs, both in the serum and CM, appeared to be similar as they supported the formation of granulocyte (G), MØ (M) and GM colonies, in vitro, in similar proportion; GM colonies were maximum (>80%). Further, LDAA-12 induced significantly (p&#60;0.05) high GM-CSF levels both in serum and CM (19±3 and 15±2 ng/ml, respectively), as compared to the controls. Neutralizing (100%) goat anti-mouse tumour necrosis factor-α (TNF-α) immunoglobulin G did not affect the LDAA-12-induced CSF production by MØs, indicating it to be TNF-α-independent. LDAA-12 induced de novo CSF production, as MØs co-treated with LDAA-12 and cycloheximide (50 μg/ml) did not elaborate CSFs. The CSF-inducing capability of LDAA-12 appeared to be heat (70 C; 1 h)-labile, destroyed by proteases (pronase E and trypsin) and was unaffected by sodium periodate treatment. In LDAA-12-treated mice, the splenic and femur colony forming unit-GM counts showed a maximum of 2.2- and 1.9-fold increase, respectively, as compared to the controls. These data are the first to directly demonstrate that L. donovani amastigote components can induce the production of CSFs that may play important role(s) in the pathogenesis of visceral leishmaniasis. [Copyright &y& Elsevier]

High density and long multiwalled carbon nanotubes are deposited using nickel clusters formed from an electrodeposited nickel coating treated by ammonia. Tubes of length 40–50 μm having bamboo shaped structure are aligned nearly parallel to the copper substrate. The inner diameter of the tubes is in the range 20–50 nm. The selected area and nano area diffraction spots clearly show the crystalline nature of nickel clusters. At some locations of the samples in the vicinity of graphite layers, Ni3C phase is also detected. The formation of the Ni3C phase that is unstable at high temperature supports the idea of a vapor–liquid–solid (VLS) mechanism for the growth of the tubes. [Copyright &y& Elsevier]

In in-vitro, co-treatment with rm GM-CSF (3.2ng/ml) and TGG (10 SP -9 sp M) has shown maximum inhibition of intra-cellular amastigote growth than individual treatments of rm GM-CSF and TGG. Here, we have reported the bioimmunotherapeutic effect of recombinant mouse granulocyte-macrophage colony-stimulating factor (rm GM-CSF) and a synthetic enkephalin fragmented peptide Tyr-Gly-Gly (TGG) in L. donovani-infected BALB/c mice. rm GM-CSF (23kDa) is an immunoregulatory glycoprotein cytokine, regulates the activation status of the mature macrophages and plays an important role in host defence. In both in-vitro and in-vivo the combined bioimmunothearapeutic effect of rm GM-CSF and TGG was annulled by the treatment of anti rm GM-CSF antibody and naloxone, a non-selective opioid receptor blocker. [Extracted from the article]