Engineering nanoporosity for Ti ion irradiated Mylar (PET) polymer by positron beam

The interconnected, molecular sized pores of microporous materials as well as of nonporous materials are of great interest for absorption, separation and catalytic applications because of their large accessible surface area. Swift heavy ion (SHI) irradiation is a useful technique for the physical and chemical modifications of the polymers. To obtain calibrated pores in cylindrical shape the etching rate along the tracks should be essentially higher than the etching rate of undamaged polymer. Multiple pores, due to overlapping of the pores and inhomogeneous pore distribution, may arise due to high pore density and non-uniform target thickness. The shape of the pores in the polymers is affected by the conditions of chemical etching used for enlarging the latent track. It is well-established that pore size is the determining parameter for hydrogen storage as well as for nanofiltration. Slow positron beam in addition to Doppler Broadening Spectroscopy (DBS) is a useful technique to evaluate the nanoporosity of polymers.     

Amyloid-β Inspired Short Peptide Amphiphile Facilitates Synthesis of Silver Nanoparticles as Potential Antibacterial Agents

An amyloid-β inspired biocompatible short peptide amphiphile (sPA) molecule was used for controlled and targeted delivery of bioactive silver nanoparticles via transforming sPA nanostructures. Such sPA-AgNPs hybrid structures can be further used to develop antibacterial materials to combat emerging bacterial resistance. Due to the excellent antibacterial activity of silver, the growth of clinically relevant bacteria was inhibited in the presence of AgNPs-sPA hybrids. Bacterial tests demonstrated that the high biocompatibility and low cytotoxicity of the designed sPA allow it to work as a model drug delivery agent. It therefore shows great potential in locally addressing bacterial infections. The results of our study suggest that these nanodevices have the potential to trap and then engage in the facile delivery of their chemical payload at the target site, thereby working as potential delivery materials. This system has potential therapeutic value for the treatment of microbiota triggered progression of neurodegenerative diseases.     

Enhanced U-Net segmentation with ensemble convolutional neural network for automated skin disease classification

Knowledge and Information Systems - In recent years, skin-related problems induce psychological problems and also injure physical health, particularly if the patient’s face was disfigured or...     

Morphology,Mineralogy and Mixing of Individual Atmospheric Particles Over Kanpur (IGP): Relevance of Homogeneous Equivalent Sphere Approximation in Radiative Models

Estimation of the direct radiative forcing (DRF) by atmospheric particles is uncertain to a large extent owing to uncertainties in their morphology (shape and size), mixing states, and chemical composition. A region-specific database of the aforementioned physico-chemical properties (at individual particle level) is necessary to improve numerically-estimated optical and radiative properties. Till date, there is no detailed observation of the above mentioned properties over Kanpur in the Indo-Gangetic Plain (IGP). To fill this gap, an experiment was carried out at Kanpur (IITK; 26.52°N, 80.23°E, 142 m msl), India from April to July, 2011. Particle types broadly classified as (a) Cu-rich particles mixed with carbon and sulphur (b) dust and clays mixed with carbonaceous species (c) Fe-rich particles mixed with carbon and sulfur and (d) calcite (CaCO₃) particles aged with nitrate, were observed. The frequency distributions of aspect ratio (AR; indicator of extent of particle non-sphericity) of total 708 particles from April to June reveal that particles with aspect ratio range >1.2 to ≤1.4 were abundant throughout the experiment except during June when it was found to shift to high AR range, >1.4 to ≤1.6 (followed with another peak of AR i.e. >2 to ≤2.4) due to dust storm conditions enhancing the occurrence of more non-spherical particles over the sampling site. The spherical particles (and close to spherical shape; AR range, 1.0 to ≤1.2) were found to be <20% throughout the experiment with a minimum (11.5%) during June. Consideration of Homogeneous Equivalent Sphere Approximation (HESA) in the optical/radiative model over the study region is found to be irrelevant during the campaign.     

Influence of reduced graphene oxide on structural,optical, thermal and dielectric properties of SnO2 nanoparticles

The present work has been carried out with the aim to synthesize tin oxide decorated reduce graphene oxide nanocomposite (SnO₂/RGO-Nc) via in-situ synthesis process and the influence of RGO loading on structural, optical, thermal and dielectric properties of SnO₂ has been discussed. The XRD, FESEM coupled with EDX elemental mapping, TEM, FTIR, Raman and XPS results reveal that the SnO₂ nanoparticles have been successfully incorporated onto the RGO sheets. The reduction in the energy gap of the composite sample as compared to SnO₂ measured from the Tauc’s relation can be attributed to strong coupling between RGO and SnO₂ NPs. Thermogravimetric analysis (TGA) shows improved thermal stability of the SnO₂/RGO-Nc. From the dielectric measurements, it is observed that the dielectric constant and dielectric loss decreases as frequency of applied field increases. AC conductivity of all samples increases as applied frequency increases which follows Jonscher’s power law. All composite samples show better conductivity as compared to SnO₂. This is due to the formation of continuous conductive pathway between SnO₂ and RGO sheets. Further high dielectric constant, low loss and high ac conductivity have been observed at optimum loading of RGO in SnO₂/RGO2-Nc as compared to other composite samples which is due the percolation effects. The impedance analysis exhibits only one semicircle for SnO₂ and SnO₂/RGO composite which suggests that the involvement of grain boundaries dominated over the grain contribution.     

Development of noncontact end effector for handling of bakery products

The application of automation for handling of nonrigid or semirigid products and air permeable materials is limited due to lack of suitable end effectors. The majority of robotic manipulators and end effectors are not easily applicable because of lack of contact rigidity with nonrigid or semirigid products due to their unpredictable and unstable behaviour and with materials which are sensitive to deformation, especially bakery products (baked and unbaked) in the biscuits industry (Erzincanli and Sharp, Food Control 8:185–190, 1997). Also, during the handling process, the risk of contamination is high due to direct contact with food products. Hence, the need for noncontact robotic end effectors is strongly felt. In this paper a noncontact type end effector having a rectangular cross-section designed for handling bakery products is discussed for use in the biscuits manufacturing industry. These end effectors operate on the principle of generating vacuum, which lifts the material without any mechanical contacts. The present work explores the possibility of using radial flow nozzles in the biscuits industry. The basic working principle is presented, followed by experimental results. An automatic noncontact end effector system may be found quite useful for the food handling industry.     

Length–weight relationships of five catfish species (Siluriformes) from the Ganga River,India

Knowledge of the length–weight relationships (LWRs) of fish is an important tool to understand fish body form, growth pattern, stock management and their conservation. The present study focused on investigating the length–weight relationships for five catfish species, Pachypterus atherinoides (Bloch, 1794), belonging to family Horabagridae; Batasio batasio (Hamilton, 1822) family Bagridae; Bagarius yarrelli (Sykes, 1839), family Gogangra viridescens (Hamilton, 1822); and Sisor rhabdophorus (Hamilton, 1822) belonging to family Sisoridae. Specimens were collected from the middle stretch of the Ganga River in India from November 2016 to May 2018. A total of 174 specimens of five fish species were collected, and their total lengths were measured to the nearest centimetre and the body weight to the nearest gram. The value of the parameter slope (b) of LWRs of the five species ranged from 2.86 (B. yarrelli) to 3.16 (G. viridescens), with a mean value of 2.99. The results of the present study documented the new maximum total length (TL) for P. atherinoides and S. rhabdophorus. The present study also provides the first reference regarding LWRs for S. rhabdophorus.