Search

Farmer profit can be increased and air quality improved

The genus Aeromonas is a widespread pathogen that includes more than 30 Gram-negative species, many of which are opportunistic bacteria. Aeromonas species are naturally distributed in various aquatic sources. Infectious processes in marine animals such as fish usually develop under stressful conditions, and when their immune systems are weakened. MicroRNAs (miRNAs/miRs) are short, non-coding RNAs that post-transcriptionally regulate gene expression. Their diverse biological functions, such as influencing cell development, proliferation, differentiation, tumorigenesis, metabolism, and apoptosis have been studied in various animals. Fish is the most important source of aquatic nutrients throughout the world, and its market is constantly growing. Overpopulation in aquaculture brings infectious diseases that threaten the development of aquaculture around the world. There is extensive evidence that microRNAs are involved in modulating infectious processes and regulating the inflammatory response to major bacterial fish infections, including Aeromonas. Here, we review the current literature on the fish microRNA repertoire and outline the physiological roles assigned to microRNAs to provide a foundation for future research during Aeromonas infection. Understanding the interaction between microRNAs and Aeromonas may provide clues to a remarkable strategy for preventing Aeromonas infections in fish. [ABSTRACT FROM AUTHOR]

The performance of all active photonic devices today is greatly limited by loss. Here, we show that one can engineer a low loss path in a metal-clad lossy multi-mode waveguide while simultaneously achieving high-performance active photonic devices. We leverage non-Hermitian systems operating beyond the exceptional point to enable the redistribution of losses in a multi-mode photonic waveguide. Consequently, our multi-mode waveguide offers low propagation losses for fundamental mode while other higher order modes experience prohibitively high losses. Furthermore, we show an application of this non-Hermitian waveguide platform in designing power-efficient thermo-optic phase shifters with significantly faster response times than conventional silicon-based thermo-optic phase shifters. Our device achieves a propagation loss of less than 0.02 dB μm−1 for our non-Hermitian waveguide-based phase shifters with high performance efficiency of P π ⋅ τ = 19.1 mW μs. In addition, our phase shifters have significantly faster response time (rise/fall time), τ ≈ 1.4 μs, compared to traditional silicon based thermo-optic phase shifters.

The coupled flexural-torsional vibration equations of a floating beam model, considering added fluid masses, are developed. The beam has varying bending stiffness, varying torsional stiffness and varying mass distribution; frequencies and mode shapes are calculated using Galerkin's method. Stiffness for the cracked beam (backbone) has been calculated using an energy procedure. Experimental values have been compared with the results of theoretical predictions and the agreement between the two found to be good. The frequency contour method has been used to identify the crack.

Abstract Background Virulence of the entomopathogenic nematode, Heterorhabditis indica against larvae (3rd, 4th and 5th larval instars) and pupae of citrus fruit piercing moth, Eudocima materna L. (Lepidoptera: Erebidae) was evaluated under laboratory conditions. The experiments included pathogenicity assessment of H. indica against larvae and pupae using a range of concentrations (10, 25, 50, 100 and 200 infective juveniles (IJs) larva−1 and pupa−1) as well as evaluation of their reproductive potential on different larval instars with different concentrations (50, 100, 200, 400 and 600 IJs larva−1). Results Application of increasing concentrations of IJs induced higher mortality on larval instars and pupae with mean mortality ranging from 26.6 to 100% (LC50- 3rd (14.43 IJs larva−1), 4th (17.08 IJs larva−1), 5th (23.63 IJs larva−1)) and 10–70% (LC50- 85.91 IJs pupa−1) after 48 h post-exposure, respectively. H. indica successfully reproduced in the 3rd, 4th and 5th larval instars of E. materna and their offspring emerged from the cadavers. The highest reproduction was recorded in 5th instar larvae (1,082,855 IJs larva−1) at 600 IJs larva−1 in E. materna. Conclusion The present study suggests that H. indica strain had the potential for biological control of E. materna.