On the Energy Efficiency Maximization of NOMA-Aided Downlink Networks With Dynamic User Pairing

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Effects of salinity and alkalinity on growth and survival of all-male giant freshwater prawn (Macrobrachium rosenbergii De Man, 1879) juveniles

All-male giant freshwater prawns (AMGFPs) have been a popular crop cultivated in the Mekong Delta, Vietnam, due to their proven production efficiency compared to all-female or mixed-sex prawn cultures. However, the crucial water quality factors impacting AMGFP aquaculture efficiency have yet to be elaborately investigated. Two separate experiments were randomly arranged with three replicates to evaluate the effects of salinity or alkalinity on the growth and survival of AMGFP juveniles during the grow-out period. The results show that the prawn survival rate in the salinity range of 0–15‰ varied from 66.1 to 74.8％ and in a salinity range of 0–5‰ was relatively low compared to the range of 10-15‰; however, the difference was not significant among salinities after 90 days of culture (p > 0.05). All the prawn growth performance parameters significantly decreased with increasing salinities of 0, 5, 10, and 15‰ after 30, 60, and 90 days of culture (p 0.05), and both were significantly higher than those at salinities of 10 and 15‰ (p < 0.05) after 90 days of culture. In addition, the survival rate reached 82.5–84.4％ and did not significantly differ among alkalinities of 80, 100, 120, 140, and 160 mgCaCO3 L−1. However, the growth performance parameters and yield of AMGFPs at an alkalinity of 160 mg L−1 were significantly higher than those at lower alkalinities (80, 100, 120, and 140 mg CaCO3 L−1) after 90 days of culture. Therefore, it is recommended that a salinity range of 0–5‰ and alkalinity of 160 mgCaCO3 L−1 is optimal for the growth-out culture of AMGFP juveniles

Widely targeted metabolomics reveals the species‐specific, matureness‐specific and post‐harvest‐specific discriminations in the chemical profiles of Vietnamese endemic golden camellias

International audienceSummary Vietnam is one of the countries with the highest diversity of golden camellias in the world, with more than forty endemic species. However, studies on Vietnamese golden camellias need to be expanded to fill a knowledge gap on these species' chemical profiles and pharmacological properties. This qualitative study focuses on six golden camellias: four endemic species from Tam Dao district, Vinh Phuc province, including Camellia hakodae , Camellia phanii , Camellia tamdaoensis , Camellia tienii and two species commonly cultivated in Quang Ninh province including Camellia petelotii and Camellia euphlebia . A mutual profile of 131 metabolites was obtained by using widely targeted metabolomics analysis using ultra‐performance liquid chromatography coupled with tandem mass spectrometry. Comparative metabolomics was performed among leaf extracts of six golden teas, between young and mature leaves and between freeze‐drying and oven‐drying leaves to discriminate these species, and determine the effect of developmental stage and post‐harvesting method on the plant metabolism. The PLS‐DA model successfully illustrated a clear separation of the six species and suggested apigenin C‐glycoside derivatives as chemical markers for the diversity. Young and mature leaves of all six species also produced distinguished metabolomes, differentiated by mostly amino acid derivatives. The multivariate analysis also indicated the conversion of some flavonoids and amino acids induced by heat in the drying process. These results offer metabolite markers for quality control of Vietnamese golden camellias and recommendations for their usage and preparation