Reproductive biology of rock oyster, Saccostrea cucullata (Born, 1778) along Aare-Ware rocky shore of Ratnagiri, Maharashtra, India

802-809The present study regarding the reproductive biology of Saccostrea cucullata was carried out from May 2014 to April 2016. The observation has indicated that the peak spawning season is from the month of November to January along the Aare-Ware rocky shore of Ratnagiri. For females, the maximum values of Gonado Somatic Index (GSI) were observed in November 2014 (2.8890) and November 2015 (2.9910), whereas in males, GSI values were maximum in November 2014 (2.1964) and December 2015 (2.1681). During the study, the average male: female sex ratio of 1:1.4 was observed, with a minimum of 1:1 in the month of April 2015 and a maximum (1:1.8) during December 2014, indicating predominance of females in all the months. The size of the first maturity has been estimated to be 22.2 mm which can be utilized for signifying management measures for sustainable utilization of the resource

Robotic Extrusion of Algae-Laden Hydrogels for Large-Scale Applications

A bioprinting technique for large‐scale, custom‐printed immobilization of microalgae is developed for potential applications within architecture and the built environment. Alginate‐based hydrogels with various rheology modifying polymers and varying water percentages are characterized to establish a window of operation suitable for layer‐by‐layer deposition on a large scale. Hydrogels formulated with methylcellulose and carrageenan, with water percentages ranging from 80% to 92.5%, demonstrate a dominant viscoelastic solid–like property with G′ > G″ and a low phase angle, making them the most suitable for extrusion‐based printing. A custom multimaterial pneumatic extrusion system is developed to be attached on the end effector of an industrial multiaxis robot arm, allowing precision‐based numerically controlled layered deposition of the viscous hydrogel. The relationship between the various printing parameters, namely air pressure, material viscosity, viscoelasticity, feed rate, printing distance, nozzle diameter, and the speed of printing, are characterized to achieve the desired resolution of the component. Printed prototypes are postcured in CaCl2 via crosslinking. Biocompatibility tests show that cells can survive for 21 days after printing the constructs. To demonstrate the methodology for scale‐up, a 1000 × 500 mm fibrous hydrogel panel is additively deposited with 3 different hydrogels with varying water percentages

Reproductive biology of rock oyster, Saccostrea cucullata (Born, 1778) along Aare-Ware rocky shore of Ratnagiri, Maharashtra, India

The present study regarding the reproductive biology of Saccostrea cucullata was carried out from May 2014 to April 2016. The observation has indicated that the peak spawning season is from the month of November to January along the Aare-Ware rocky shore of Ratnagiri. For females, the maximum values of Gonado Somatic Index (GSI) were observed in November 2014 (2.8890) and November 2015 (2.9910), whereas in males, GSI values were maximum in November 2014 (2.1964) and December 2015 (2.1681). During the study, the average male: female sex ratio of 1:1.4 was observed, with a minimum of 1:1 in the month of April 2015 and a maximum (1:1.8) during December 2014, indicating predominance of females in all the months. The size of the first maturity has been estimated to be 22.2 mm which can be utilized for signifying management measures for sustainable utilization of the resource

Simulations of Aerodynamic Damping for MEMS Resonators

Aerodynamic damping for MEMS resonators is studied based on the numerical solution of Boltzmann-ESBGK equation. A compact model is then developed based on numerical simulations for a wide range of Knudsen numbers. The damping predictions are compared with both Reynold equation based models and several sets of experimental data. It has been found that the structural damping is dominant at low pressures (high Knudsen numbers). For cases with small length-to-width ratios and large vibration amplitudes, the threedimensionality effects must be taken into account. Finally, an uncertainty quantification approach based on the probability transformation method has been applied to assess the influence of pressure and geometric uncertainties. The output probability density functions (PDF) of the damping ratio has been studied for various input PDF of beam geometry and ambient pressure