3D Optical data storage is demonstrated in co‐extruded multilayer films using organic materials. Co‐extrusion is able to produce films on a much larger scale at a much lower cost than current methods. The material compatibility and mechanical flexibility allow for new data formats with higher capacities to be realized.

In order to achieve a high capacity 3D optical data storage medium, a nonlinear or threshold writing process is necessary to localize data in the axial dimension. To this end, commercial multilayer discs use thermal ablation of metal films or phase change materials to realize such a threshold process. This paper addresses a threshold writing mechanism relevant to recently reported fluorescence-based data storage in dye-doped co-extruded multilayer films. To gain understanding of the essential physics, single layer spun coat films were used so that the data is easily accessible by analytical techniques. Data were written by attenuating the fluorescence using nanosecond-range exposure times from a 488 nm continuous wave laser overlapping with the single photon absorption spectrum. The threshold writing process was studied over a range of exposure times and intensities, and with different fluorescent dyes. It was found that all of the dyes have a common temperature threshold where fluorescence begins to attenuate, and the physical nature of the thermal process was investigated.

We demonstrate that fluorogenic molecules that “turn-on” upon redox reactions can sense the corrosion of iron at the single-molecule scale. We first observe the cathodic reduction of nonfluorescent resazurin to fluorescent resorufin in the presence of iron in bulk solution. The progression of corrosion is seen as a color change that is quantified as an increase in fluorescence emission intensity. We show that the fluorescence signal is directly related to the amount of electrons that are available due to corrosion progression and can be used to quantify the catalyzed increase in the rate of corrosion by NaCl. By using modern fluorescence microscopy instrumentation we detect real-time, single-molecule “turn-on” of resazurin by corrosion, overcoming the previous limitations of microscopic fluorescence corrosion detection. Analysis of the total number of individual resorufin molecules shows heterogeneities during the progression of corrosion that are not observed in ensemble measurements. Finally, we discuss the potential for single-molecule kinetic and super-resolution localization analysis of corrosion based on our findings. Single-molecule florescence microscopy opens up a new spatiotemporal regime to study corrosion at the molecular level.

Proteins within nanoporous hydrogels have important biotechnological applications in pharmaceutical purification, tissue engineering, water treatment, biosensors, and medical implants. Yet, oftentimes proteins that are functional in solution lose activity when in contact with soft, nanostructured, condensed phase materials due to perturbations in the folded state, conformation, diffusion, and adsorption dynamics of the protein by the material. Fluorescence microscopy experimentally measures the biophysical dynamics of proteins within hydrogels at the nanoscale and can overcome the limitations of conventional ensemble techniques. An explanation of the benefits of fluorescence is provided, and principles of fluorescence microscope instrumentation and analysis are discussed. Then several nanoscale fluorescence microscopies that image nanoscale protein dynamics within hydrogels are introduced. First, location-based super-resolution imaging resolves the adsorption kinetics of proteins to charged ligands within hydrogels used in pharmaceutical separations. Next, correlation-based super-resolution techniques image the heterogeneity of the nanoscale pore size of the hydrogels and the diffusion of analytes within the pores simultaneously. Finally, fluorescence resonance energy transfer imaging combined with temperature jump perturbations determines the folding and stability of a protein within hydrogels. A common finding with all three fluorescence microscopies is that heterogeneous nanoporous hydrogel materials cause variability of protein behavior dependent on gel sterics and/or interfacial electrostatic forces. Overall, in situ observations of proteins in hydrogels using fluorescence microscopies can inform and inspire soft nanomaterial design to improve the performance, shelf life, and cost of biomaterials.

In the present study, Saccharopolyspora erythraea MTCC 1103 was used for the enhanced production of erythromycin. To enhance the yield of erythromycin, effects of various parameters such as bagasse concentration, organic nitrogen source, inorganic nitrogen source, pH and temperature were analysed. It was found that bagasse can be used as an alternate carbon source in erythromycin production medium. Erythromycin production in the new formulation of bagasse based medium was found to be 512 mg/L which was 28 % higher than glucose based medium. Strain improvement was done by random UV-mutagenesis. When compared to wild type strain, mutant strain showed 40 % higher yield in production medium. Erythromycin potency assay and HPLC analysis were performed to confirm the presence of erythromycin in the partially purified samples. These optimized conditions could be used for the commercial production of this unique antibiotic which gave significant industrial perspectives.

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Background Corporate social marketing (CSM), as a type of corporate social initiative, is considered to be the most effective tool for creating social good through behavioural change. However, the relevance and benefits of CSM in the business context are largely unknown. The understanding of ‘the business case’ of CSM initiatives can provide useful insights to practitioners in this field. In this paper, we study the boundary spanning benefits of CSM in the area of employer branding. Research Questions This research aims to answer one major question: Do CSM campaigns play any role in building an organization’s employer brand? If yes, then how? Further, two associated supplementary questions include (i) how do managers perceive the use of CSM campaigns during campus engagement initiatives? (ii) how do job seekers perceive the use of CSM campaigns in campus engagement initiatives? Methods We use a qualitative research approach to answer the above questions. Using a purposive sampling method, we interviewed 6 managers who manage and 13 management students who attended campus engagement initiatives. The research was carried out in an emerging economy context, namely India, which has had several successful CSM campaigns and is home to the youngest working population, particularly millennials. Results The study shows that CSM leads to three major employer branding outcomes – increasing employer awareness, enhancing employer attractiveness and differentiating an employer from other competing organizations. Students prefer employers who provide them opportunities to work for society and are even willing to accept a lower pay in such organizations. Managers revealed the importance of showcasing CSMs during campus presentations and confirmed the relevance of social causes in employer branding initiatives. Recommendations for Practice The study offers useful insights to human resource managers on the role of CSM campaigns in creating employer awareness and attracting talent during campus engagement. We recommend that CSM campaigns be leveraged during campus engagement sessions for achieving differentiation in a competitive talent market. Lesser-known employers can use CSM campaigns for increasing employer awareness among potential student recruits. Organizations may proactively design and implement CSM campaigns, consistent with their values and mission, for the positive spill-over effects it can yield for their employer brand. The study aims to contribute to the CSM literature by studying the boundary spanning role of CSM in employer branding.

Most approaches to high-capacity 3D optical data storage (ODS) require confinement of the writing action to a specified depth in the writing medium. This is achieved by a nonlinear photoresponse, usually two-photon absorption, which requires a pulsed long-wavelength source. Fluorescence photobleaching of a dye/polymer composite can be used at a short wavelength to store data at the diffraction limit in a layered storage medium. In this work, the writing response of a bleachable dye/polymer system illuminated with single pulses of various duration obtained from a modulated 405 nm wavelength CW laser was studied. A transition from a linear to nonlinear writing mechanism was observed near the microsecond time scale. Concentration-dependent measurements indicate that a photothermal mechanism accounts for the nonlinear response in the short pulse, higher power regime. This nonlinear response may be useful for realizing terabyte scale ODS in multilayered polymer media.