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Industry in developing nations has not attracted much attention from standard theorists. One of the reasons is that developing countries are considered 'standard takers.' As a result, the limited scholarship on standards in the context of developing countries largely remains occupied with global value chains and standards. Besides, industries in these countries are often marked with various degrees of informality. Due to this, the innate structure and governance of these industries depend a lot on socio-economic relations, over and above the formal legal and regulatory structures. This makes operationalization of standards much more complex than simple adoption of standards in codified and documented form, dominantly considered in mainstream discourse on standards. This paper attempts to answer a few of the limitations highlighted and adds to the scholarship on standards in the context of developing countries by considering the case of Aligarh padlock industry. The paper explores the socio-economic dynamics which govern the emergence, adherence and proliferation of these standards. To this end, the paper considers standards as a form of knowledge that brings order to an industry. Further, adapting upon the literature on global value chain and its role in standard proliferation and informality, the paper explores the role of local value chain in the proliferation of industry-level standards. [ABSTRACT FROM AUTHOR]

Uncharacterized and hypothetical pathogenicity genes of Colletotrichum orbiculare inciting anthracnose of cucumber are poorly annotated but could be potential antifungal targets in anthracnose control. Hence, to associate them with specific functions in fungal-host interactions for exploitation in anthracnose control, their responses to reactive oxygen species produced due to oxidative burst and constitutive or induced phenolics, the earliest known defence mechanisms of host plants were assessed. Among commercially available related phenolic compounds, at the lowest concentration of 1 mM, ferulic and chlorogenic acids were less toxic to the pathogen. Among the phenolics, a less significant expression of superoxide dismutase coupled with a strong expression of catalase in ferulic acid greater than that in menadione and hydrogen peroxide, respectively indicated its oxidative effect through generation of radicles similar to that of hydrogen peroxide. However, lack of expression of beta-ketoadipate pathway genes in response to the phenolic acids indicated the role of other phenol metabolizing genes of the pathogen. In planta expression followed by constitutive expression of uncharacterized and hypothetical pathogenicity genes of C. orbiculare in a minimal medium indicated that 6 of the genes are not redundant and may function under stress conditions. Among the genes, significant expression of ENH87556 in menadione (1.3-fold) together with a weak expression in hydrogen peroxide in relation to untreated control indicated its role in oxidative stress generated due to the superoxide radical of menadione. Additionally, a strong expression (3.8-fold) of the gene in ferulic acid greater than that of either control, minimal medium or minimal medium with leaf extract indicated its role in phenol metabolism. Thus, the gene could be a potential molecular target for anthracnose control upon validation by functional analysis. [ABSTRACT FROM AUTHOR]

The interaction between two polymer grafted surfaces is important in many applications, such as nanocomposites, colloid stabilization, and polymer alloys. In our previous work [Jain et al., J. Chem. Phys. 128, 154910 (2008)], we showed that interfacial statistical associating fluid density theory (iSAFT) successfully calculates the structure of grafted polymer chains in the absence/presence of a free polymer. In the current work, we have applied this density functional theory to calculate the force of interaction between two such grafted monolayers in implicit good solvent conditions. In particular, we have considered the case where the segment sizes of the free (σf) and grafted (σg) polymers are different. The interactions between the two monolayers in the absence of the free polymer are always repulsive. However, in the presence of the free polymer, the force either can be purely repulsive or can have an attractive minimum depending upon the relative chain lengths of the free (Nf) and grafted polymers (Ng). The attractive minimum is observed only when the ratio α=Nf/Ng is greater than a critical value. We find that these critical values of α satisfy the following scaling relation: ρgNgβ3∝α-λ, where β=σf/σg and λ is the scaling exponent. For β=1 or the same segment sizes of the free and grafted polymers, this scaling relation is in agreement with those from previous theoretical studies using self-consistent field theory (SCFT). Detailed comparisons between iSAFT and SCFT are made for the structures of the monolayers and their forces of interaction. These comparisons lead to interesting implications for the modeling of nanocomposite thermodynamics. [ABSTRACT FROM AUTHOR]

By using a classical density functional theory (interfacial statistical associating fluid theory), we investigate the structure and effective forces in nonadsorbing polymer-colloid mixtures. The theory is tested under a wide range of conditions and performs very well in comparison to simulation data. A comprehensive study is conducted characterizing the role of polymer concentration, particle/polymer-segment size ratio, and polymer chain length on the structure, polymer induced depletion forces, and the colloid-colloid osmotic second virial coefficient. The theory correctly captures a depletion layer on two different length scales, one on the order of the segment diameter (semidilute regime) and the other on the order of the polymer radius of gyration (dilute regime). The particle/polymer-segment size ratio is demonstrated to play a significant role on the polymer structure near the particle surface at low polymer concentrations, but this effect diminishes at higher polymer concentrations. Results for the polymer-mediated mean force between colloidal particles show that increasing the concentration of the polymer solution encourages particle-particle attraction, while decreasing the range of depletion attraction. At intermediate to high concentrations, depletion attraction can be coupled to a midrange repulsion, especially for colloids in solutions of short chains. Colloid-colloid second virial coefficient calculations indicate that the net repulsion between colloids at low polymer densities gives way to net attraction at higher densities, in agreement with available simulation data. Furthermore, the results indicate a higher tendency toward colloidal aggregation for larger colloids in solutions of longer chains. [ABSTRACT FROM AUTHOR]

Modified interfacial statistical associating fluid theory density functional theory is extended to tethered polymer chains in the absence or presence of free polymer chains. The structures of the “dry” and “wet” polymer brushes have been calculated and compared with simulation results available in the literature. The comparisons show that the theory accurately predicts the structure of the tethered polymer brush. The average brush heights calculated from the theory agree with well-established scaling theories for tethered polymers. However, these scaling theories cannot predict the detailed structure, accurately. The effects of the segment-segment interactions of the tethered polymer and the free polymer have been effectively captured by the theory. [ABSTRACT FROM AUTHOR]

A density functional theory based on Wertheim’s first order perturbation theory is developed for inhomogeneous complex fluids. The theory is derived along similar lines as interfacial statistical associating fluid theory [S. Tripathi and W. G. Chapman, J. Chem. Phys. 122, 094506 (2005)]. However, the derivation is more general and applies broadly to a range of systems, retaining the simplicity of a segment density based theory. Furthermore, the theory gives the exact density profile for ideal chains in an external field. The general avail of the theory has been demonstrated by applying the theory to lipids near surfaces, lipid bilayers, and copolymer thin films. The theoretical results show excellent agreement with the results from molecular simulations. [ABSTRACT FROM AUTHOR]