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Pendent functionalization of biodegradable polymers provides unique importance in biological applications. In this work, we have synthesized a polymeric nanocarrier for the controlled release of the anticancer drug doxorubicin (DOXI). Inspired by the pH responsiveness of acylhydrazine bonds along with the interesting self-assembly behavior of amphiphilic copolymers, this report delineates the development of a PEG-SS-PCL-DOXI copolymer consisting of DOXI, PEG, and a caprolactone backbone. First, the inclusion of a PEG moiety in the copolymer helps to achieve biocompatibility and aqueous solubility as well as a prolonged circulation time of the nanocarrier. Second, an acid-sensitive acylhydrazine-based linkage is chosen to attach DOXI to trigger sustained drug release, whereas the inclusion of an enzymatically cleavable disulfide linkage in the backbone adds to the advantage of backbone biodegradability at the intracellular level.

With the aim to develop chemical adsorbents that are inherently nontoxic to living beings and the environment, a gel system based on thiol− norbornene photoclick chemistry was developed. Norbornene was strategically functionalized with different poly(ethylene glycol) (PEG) chains to produce PEGfunctionalized macromonomers. The influence of incorporating PEG in the crosslinked network was evaluated on the basis of its physical properties and dye-removing efficiency from aqueous solutions. The excellent swelling ability of the gels in organic solvents was found to improve with the PEG chain length. The rheological measurements of the as-synthesized materials also exhibited the presence of elasticity in the network, and a decrease in storage and loss moduli was observed with an increase in PEG molecular weight. The materials possess excellent thermal stability, which enhanced with an increase in PEG chain length, as revealed from thermogravimetric analysis (TGA). Differential scanning calorimetry (DSC) studies revealed the tendency of higher-molecular-weight PEG to form a crystalline phase in the network. Kinetic studies of dye removal from aqueous solutions by the as-prepared cross-linked networks indicate that the dye removal proceeds via pseudo-second-order kinetics. The study of adsorption isotherm of the removal process indicates that the adsorption follows the Langmuir isotherm model. In this present work, we have thoroughly evaluated the influence of PEG chain length on several physical properties and toxic cationic dye removal efficiencies of thiol−norbornene photo-cross-linked networks.

The past decade has been very productive for cellular operators of Pakistan, as their subscribers have grown exponentially with increase in revenue. After this wave of rising, the operators have now reached to saturation level, with the highest teledensity of all time. These Cellular Networks consist of Cell sites, which need electrical power to run. Because of electrical power shortage in Pakistan, the power needs of cell site are fulfilled by the use of electrical power generators which are installed on each site. These generators run on fossil fuel, a large amount of which is being theft from sites. This has very negative impact on Network availability and Operator's operational expenditure. To cope with this major issue of fuel theft, an embedded system is being designed and tested. This paper highlights this issue of the telecom sector and discusses the design and results of the proposed system. This system would reduce the cell site operational cost and will increase its availability in the service area.

Sustainability of old buildings is constantly challenged due to its non-compliance with energy saving practices. Old buildings which aim to deploy technologies to improve thermal comfort face some infrastructure constraints. The sustainability of such buildings is dependent on occupant's thermal comfort, low carbon emissions and reduced energy consumption. Such buildings face restraints in the way in which wired and wireless technologies could be used to implement sensing and control actions. Constraints include infrastructure limitations and space usage restrictions. This paper discusses retrofit solutions for old buildings for minimizing energy consumption and maximizing the occupant's comfort. The implementation of the retrofitted solution in an existing old building with minimal infrastructure change is elaborated. This includes implementation of thermal comfort based algorithm for zonal damper control, indoor air quality based window control and light sensor based blinds control. The sensing and control action is based on indigenous circuits communicating through ZigBee wireless protocol in Wireless SensorNetwork (WSN) of motes. A WingZ gateway runs the thermal comfort algorithm and acts as command centre for the WSN. The research aims to demonstrate the possibility of extending sustainability of existing old buildings by using energy conscious building automation solutions where large scale infrastructure change is not possible.

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We report the design and synthesis of thiol-norbornene based ingenious gels with pendent quaternary ammonium substituents on the norbornene backbone that are conducive to remove toxic anionic azo dye acid orange 7 (AO7) from wastewater. Three different alkyl side chains on the dangling quaternary ammonium moiety were chosen prudently and their performance towards removal of azo dye was scrutinised. The characterisation of all the precursor monomers and the ensuing gels were accomplished by 1 H, 13 C NMR and Mass spectrometry. The influence of extent of crosslinking on the solvent uptake ability was investigated and the swelling nature of the gels were correlated with the solubility parameter of different solvents. The surface morphology of the gels as visualised by FE-SEM analysis, revealed macropores in the range 4-12 μm. The relationship between the composition of quaternary ammonium moiety on the gels and their viscoelastic properties was realised. The dye removal kinetics as observed from UV-Vis spectra were best correlated with the pseudo-second-order model and the adsorption isotherm of dye removal process was best fitted with the Langmuir isotherm model with high correlation coefficient. The material was found to be fairly recyclable up to 10 th cycles with loss of only 8% efficiency. To the best of our knowledge, this is the first ever report on the removal of anionic dye based on thiolnorbornene photo crosslinked network. We believe that this design and composition-property relationship will enthuse the researchers to develop efficient chemical adsorbents based on environmentally benign systems.