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Fused deposition modeling is preferred to fabricate the biodegradable poly lactic acid (PLA) parts, owing to its impeccable characteristics, such as, customization, waste minimization and scalability. However, limited printing volume constraint restricts the ubiquitous applications of this technique. The current experimental investigation is focused on the employment of ultrasonic welding technique to address the printing volume challenge. The effect of infill density, type of energy directors (triangular (TED), semicircular (SCED) and cross energy directors (CED)) and different levels of welding parameters have been investigated on the mechanical and thermal behavior of welded joints. Presence of rasters and gap between them plays a pivotal role in overall heat generation at weld interface. The joint performance of 3D printed parts has also been compared with injection molded specimens of same material. All printed/molded welded specimens with CED recorded higher tensile strength than equivalent specimens with TED and SCED. Moreover, These specimens also performed better than specimens without energy directors and recorded higher tensile strength, that is, 317, 73.5, 59.7 and 42% higher for injection molded (IM), 80%, 90% and 100% infill density (IF) specimens without energy directors at lower level of welding parameters (LLWP). These specimens also exhibited higher tensile strength at optimal levels of welding parameters. Although, at medium and higher levels of welding parameters, both printed/molded specimens with CED observed comparatively more degradation of joints due to higher concentration of energy at weld interface. The dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG) and field emission scanning electron microscopy (FESEM) analysis have been performed to substantiate the experimental results., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

We studied the impact of weather parameters on the population build-up of Brevicoryne brassicae (L.) (Cabbage aphid), Lipaphis erysimi (Kalt.) (Mustard aphid), Myzus persicae (Sulzer) (Green peach aphid) and their biocontrol agents (coccinellids, syrphids, and a parasitoid, Diaeretiella rapae M'Intosh) on oilseed brassicas in Himachal Pradesh, India, during winters from 2016-2017 to 2018-2019. The temperature and sunshine resulted in the build-up of B. brassicae and their biocontrol agents' population, while rainfall and relative humidity caused a negative influence at surveyed locations. The L. erysimi and M. persicae populations showed an inverse correlation with the density-independent factors at most locations. Correlation coefficients indicated a negative correlation of the coccinellids population with the build-up of L. erysimi and M. persicae, while the predator population was positively related to the B. brassicae population at maximum locations. Parasitization by D. rapae showed a negative relationship with the aphid population. Stepwise regression analysis showed that minimum temperature and rainfall had a significant effect on the variability in the population of aphids. The predictive model could interpret more than 90% variation by minimum temperature in the coccinellid population at the surveyed locations. Further, regression analysis with temperature could explain up to 94% variability in parasitization by D. rapae. This study will contribute to predicting the changes that may occur in a population of aphids concerning the weather., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Moraxella species are gram-negative diplobacilli and are rare cause of bacterial keratitis. We report a case of a 55-year-old woman presented with pain, redness and profound decrease in vision in both eyes for 2 weeks. One month back she had been treated as acute follicular conjunctivitis elsewhere. She had been treated with ofloxacin drops. On examination, she had central oval full-thickness infiltrate with thinning of cornea and hypopyon in both eyes. She had pseudomembrane in the tarsal conjunctiva. Corneal culture, done separately, showed isolation of Moraxella species, which was resistant to fluoroquinolones. She responded to fortified amikacin and ulcer healed with best-corrected vision of 6/24 and 6/18 in right and left eye respectively. Moraxella keratitis can cause severe keratitis. Conjunctivitis may be complicated by keratitis. Antibiotic resistance can cause problem. Bilateral keratitis should be referred promptly to higher centers if not responding well to treatment.

The stringent requirements on size and power consumption constrain the conventional hearing aid devices from providing the patients an economic and user friendly solution, specifically for better noise cancellation. With the advancements in technologies such as integrated circuits design, wireless communications and digital signal processing techniques, the wireless hearing aids having multi-microphones, analog, digital and mixed signals and radio frequency signals processing circuits, DSP and programmable units seem to be promising to provide enhanced performance. The focus of this paper is about the system simulation of a typical wireless hearing aid using Agilent Advanced Design System™. The behavioral modeling features are exploited to enable the whole system simulations including electro-acoustic transducers. A few system level simulation results are included.