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Polymer nanocomposites have attracted global attention as a metal replacement for electrical and electronic applications. Graphene nanoplatelets (GNPs) are widely used as a nanoreinforcement to enhance the functional and structural properties of thermoset and thermoplastic polymers. In the present study, ABS nanocomposites were prepared by reinforcing 3–15 wt.% GNPs in steps of 3 wt.%. The neat ABS and ABS+GNP nanocomposite specimens for the mechanical test were prepared using injection molding, followed by extrusion, as per American Society for Testing and Materials (ASTM) standards. It was found that the modulus of ABS improved due to the reinforcement of GNPs. Additionally, we noticed higher thermal stability of nanocomposites due to the faster heat-conducting path developed in the nanocomposites by the presence of GNPs. However, observed agglomeration of GNPs at higher concentrations and poor wetting with ABS led to the deterioration of the mechanical properties of the nanocomposites. Moreover, 350 µm thick nanocomposite films were manufactured by compression molding, followed by the extrusion method, and we investigated their electrical conductivity, magnetic permeability, permittivity, and electromagnetic-wave-shielding effectiveness. The developed nanocomposites showed improved conductivity and effective electromagnetic wave shielding by absorption. The 15 wt.% GNP-reinforced ABS composite film showed a maximum shielding effectiveness of 30 dB in the X-band.

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In this work Graphene nanoplatelets (GNPs) filled with Linear low-density polyethylene (LLDPE), nanocomposite films designated as LLDPE+1%GNP and LLDPE+5% GNP were manufactured using LLDPE pristine granules, 1 wt. % GNPs-LLDPE, and 5wt. % GNPs-LLDPE masterbatch granules by the extrusion-blow molding process. It was found that the ductile behaviour of neat LLDPE film and nanocomposite films are anisotropic in the machine direction (MD) and transverse direction (TD). The tensile strength of neat LLDPE films in the MD and TD is 25.93 & 20MPa. LLDPE+1GNPs nanocomposite films showed higher tensile strength in the MD and TD 28.38 & 23MPa, and LLDPE+5GNPs nanocomposite films showed 24.36 & 23MPa respectively. The high concentration of GNPs in LLDPE acts as plasticizers increased the elongation, reduced the strength, and increased the rate of thermal degradation. The XRD results reveal additional peeks observed in LLDPE+5GNPs nanocomposite films infer the slight change in crystallinity as compared to neat LLDPE film. This is evident in the change of tensile behaviour of nanocomposite as compared to LLDPE.

Aim: To measure macular thickness by optical coherence tomography (OCT) in various grades of diabetic retinopathy with no clinically significant macular edema (CSME) and its comparison with non-diabetics. Design: Prospective cross–sectional study. Methods: Macular thickness was measured by OCT in 72 healthy volunteers (107 control eyes), 45 patients with mild and moderate non-proliferative diabetic retinopathy (NPDR) (78 eyes) and 37 patients with severe NPDR and proliferative diabetic retinopathy (PDR) (66 eyes). Patients with diabetic macular edema (DME) as assessed by stereoscopic evaluation or photographs were excluded. One-way ANOVA test to compare the mean thickness and Tukey's test for multiple comparison between groups were used. Results: Central subfield thickness (CST) was 238.57 ± 25.077 µm, 251.22 ± 24.649 µm, and 270.45 ± 28.956 µm in the three groups respectively. As the severity of retinopathy increased, the macular thickness significantly increased (p = < 0.001) in all the nine zones on OCT. There was a significant increase in CST noted in all the grades of retinopathy when compared with non-diabetics (p = 0.004, p = < 0.0001). No significant difference in macular thickness was noted between genders, irrespective of their groups (p = 0.72), or between the three groups in all the nine zones (p = 0.609). Conclusion: There is a significant increase in CST in all grades of retinopathy, as well as with increasing severity of retinopathy when compared to non-diabetics. This warrants the need to obtain OCT measurements even in patients with moderate NPDR without CSME to rule out subclinical DME.

We report the case of a 1-year-old child who presented with complaints of redness and defective vision since birth. The child had no systemic abnormalities. On examination, complete keratinization of the bulbar conjunctiva and cornea was noted with dry, lustreless and irregular surface. Corneal sensation was intact. Orbital MRI revealed bilateral agenesis of the lacrimal gland with normal salivary glands. The child was given vitamin supplementation, cyclosporine eye drops along with lubricants and tape tarsorrhaphy in the night. Permanent occlusion of both the lower puncta was done. There was decreased ocular surface congestion, with frequent wetting of the ocular surface, which continued in the months to follow. We present a case of isolated bilateral lacrimal gland agenesis with normal salivary glands, a rare cause of dry eye in children. An early diagnosis and conservative management can help in maintaining functional vision in such cases.

In this paper an autopilot system is designed for cruise mode of a fixed wing unmanned aerial vehicle (UAV). The biggest challenge is to maneuver UAV at lower altitudes while overcoming strong coupling between longitudinal and lateral mode. The six-DoF simulation model of the UAV plant under consideration is a non-linear one, to control it for cruise mode it is trimmed at cruise conditions for decoupling of plant model. The control design is divided into two phase, in first phase PID controllers are designed for individual parameter hold related to the cruise flight envelope. In the next phase a decoupled single control with the capabilities of controlling all the parameters for cruise mode is designed. Parallel control loop structure are designed to generate the throttle and elevator control command which indeed control forward speed and altitude of the UAV during cruise. This paper will thus discuss the steps by step procedures in setting up the non-linear flight model/plant, trimming method, flight dynamics, designing control laws and plant validation using simulation software. The mathematical modelling and simulation of UAV aerodynamic wind tunnel test data are adopted from Indian Institute of S cience, Bangalore.