Abstract The objective of the present study was to evaluate growth, biochemical, hematological and intestinal enzymes responses and survival of Nile tilapia juveniles fed a diet containing the ...essential oil of lemongrass Cymbopogum flexuosus (EOCF) and infected by Aeromonas hydrophila. Five diets were evaluated (in quadruplicate) with increasing levels of EOCF (0.0 - control; 0.25; 0.50; 1.0 and 2.0 mL kg diet-1). On day 45, eight fish per treatment were sampled and blood, liver and intestine samples were taken. Others eight fish per treatment were infected with A. hydrophila followed by a 15-day period of observation. Citral is the main constituent of EOCF. The inclusion of 2.0 mL EOCF kg diet-1 increased specific growth rate and survival after A. hydrophila infection and decreased feed conversion ratio of Nile tilapia. In general, higher concentrations of EOCF in the diet reduced plasma glucose and triglycerides levels, and increased plasma amino acids, alanine aminotransferase (ALT) and hepatic ALT levels, hematological parameters, and the activity of intestinal enzymes. It was concluded that the inclusion of 2.0 mL EOCF kg diet-1 improved growth performance, biochemical and physiological responses and decreased mortality of Nile tilapia after A. hydrophila infection.
We present a comprehensive review of the advent and impact of continuous flow chemistry with regard to the synthesis of natural products and drugs, important pharmaceutical products and definitely ...responsible for a revolution in modern healthcare. We detail the beginnings of modern drugs and the large scale batch mode of production, both chemical and microbiological. The introduction of modern continuous flow chemistry is then presented, both as a technological tool for enabling organic chemistry, and as a fundamental research endeavor. This part details the syntheses of bioactive natural products and commercial drugs.
Mauritia flexuosa L. f. is a native palm tree from the South American Amazon rainforest commercialized in food, cosmetics and medicine. This paper reported the antioxidant, antimicrobial activities ...and characterization of phenolics from buriti leafs, trunk and fruit extracts. The total phenolics of the buriti extracts ranged from 378.07±3.12 to 86.89±3.15mg GAEq/100g and flavonoid content ranged from 567.16±1.15 to 246.84±1.11mg QUEREq/100g. The antioxidant activity assays with EC50 of 12.28±0.022 to 19.58±0.064mg/mL revealed the antioxidant capacity of M. flexuosa extracts. Results of the antimicrobial tests against some pathogenic bacteria revealed its strong ability to inhibit the growth of pathogen with low MIC values, where the best results were found with the leaf extract against the pathogen Pseudomonas aeruginosa (MIC 50μg/mL). The characterization of the phenolic compounds using Ultra Performance Liquid Chromatography coupled to Electrospray Ionization Tandem Mass Spectrometry (UPLC–ESI-MS/MS) was based on CID experiments of the observed precursors, thus 13 compounds were tentatively identified ((+)-catechin, caffeic acid hexoside, chlorogenic acid, quercetin, narigenin, myricetin, vitexin, scoparin, rutin, cyanidin-3-rutinoside, cyanidin-3-glucoside, (−)-epicatechin and kaempferol). These results indicate that antioxidant and antimicrobial activities in buriti phenolic extracts are quite potent and implicate the presence of compounds with potent free-radical-scavenging activity.
► The Amazonian fruit buriti (Mauritia flexuosa) is a source of phenolic compounds. ► Different parts of M. flexuosa showed different antioxidant capacities. ► Low antimicrobial activity was detected for the phenolic extracts. ► The main phenolic compounds were identified by UPLC–MS/MS.
ABSTRACT
MicroRNAs (miRNAs) are endogenous, small non‐coding RNAs known to regulate expression of protein‐coding genes. A large proportion of miRNAs are highly conserved, localized as clusters in the ...genome, transcribed together from physically adjacent miRNAs and show similar expression profiles. Since a single miRNA can target multiple genes and miRNA clusters contain multiple miRNAs, it is important to understand their regulation, effects and various biological functions. Like protein‐coding genes, miRNA clusters are also regulated by genetic and epigenetic events. These clusters can potentially regulate every aspect of cellular function including growth, proliferation, differentiation, development, metabolism, infection, immunity, cell death, organellar biogenesis, messenger signalling, DNA repair and self‐renewal, among others. Dysregulation of miRNA clusters leading to altered biological functions is key to the pathogenesis of many diseases including carcinogenesis. Here, we review recent advances in miRNA cluster research and discuss their regulation and biological functions in pathological conditions.
Summary
Congenital bilateral absence of the vas deferens (CBAVD) is found in 1% to 2% of males with infertility and is present in 6% of obstructive azoospermia cases. Nearly 95% of men with cystic ...fibrosis (CF, an autosomal recessive disorder) have CBAVD. There are genetic links between CBAVD and CF. Some mutations in the gene encoding cystic fibrosis transmembrane conductance regulator (CFTR) can lead to CBAVD as a monosymptomatic form of CF. With the use of assisted reproductive techniques (ART), especially testicular or epididymal sperm aspiration, intracytoplasmic sperm injection, and in vitro fertilization, it is possible that men with CBAVD can produce offspring. Therefore, genetic counseling should be offered to couples undergoing ART to discuss the probability of having offspring that carry CFTR gene mutations. The aim of this review was to present the main cause of CBAVD, to call attention to its implications for assisted reproduction, and to show the importance of genetic counseling for couples where men have CBAVD, as they can have offspring with a lethal disease.
Soils provide essential ecosystem services for supporting both human and ecosystem needs and has been under pressures resulting from the intensification and expansion of human activities. In the last ...15 years, substantial efforts have been made to quantify the impacts on soils derived from production systems and their related supply chains. In this study, a systematic, qualitative evaluation of up-to-date models connecting land occupation and land transformation to soil impact indicators (e.g., soil properties, functions, and threats) is performed. The focus is on models that may be applied for assessing supply chains, namely in the context of life cycle assessment (LCA). A range of eleven soil-related models was selected and evaluated against different criteria, including scientific soundness, stakeholders' acceptance, reproducibility, and the applicability of models from the perspective of LCA practitioners. Additionally, this study proposes a new land use cause-effect chain to qualify the impacts of land use on soils. None of the models is fulfilling all the criteria and includes comprehensively the cause-effect impact pathways. Notably, trade-offs were most frequent between the relevance of the modeled impact processes and the models' applicability. On the one hand, models proposing multi-indicators cover several drivers of impacts and have a broader scope. On the other hand, several models just focus on one driver of impact, but may provide more relevant impact characterization. Our results provide common ground for the development and identification of models that provide a comprehensive and robust assessment of land use change and land use impacts on soils. Indeed, to ensure both a comprehensive and relevant characterization of impacts, the study identifies several research needs for further models' developments, namely: 1) adopting a common land use cause-effect chain and land use classification; 2) accounting for different land management and land use intensities; 3) expanding the inventory data beyond the accounting of the area related to a certain land use; 4) assessing the added value of multi-indicators compared to single indicators, including the reduction of possible redundancies in the impact evaluation; 5) improving consistency from midpoint to endpoint characterization, especially the link with biodiversity; 6) guiding the calculation of normalization factors; and 7) assessing systematically model's uncertainty.
•The study evaluated models focusing on soil properties and functions.•Both single-indicators and multi-indicators have been assessed.•Models were evaluated against criteria from scientific robustness to applicability in LCA.•No one model meets all the criteria needed to fully depict of impacts on soil properties and function.•Further research is needed to improve soil modeling and their applicability in LCA.
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•Interest for biodegradable polymers is increasing driven by sustainability trend.•Use of CNC as reinforcement in polymer nanocomposites is highlighted.•Effect of CNCs on the overall ...properties of the nanocomposites is discussed.•Focus on rheological, thermal, mechanical, barrier and biodegradation properties.
Cellulose nanocrystals (CNCs) are considered as one of the most attractive renewable reinforcements for biodegradable polymers due to their promising properties and broad range of applications in several fields. However, the knowledge of CNCs effect on the overall properties of these CNC-based nanocomposites is not fully clarified. This review proposes a comprehensive understanding on the effect of CNCs on the rheological, thermal, mechanical, barrier and biodegradation properties of the main biodegradable polymers. This further understanding is expected to facilitate progress in various sectors of nanotechnology and materials science.
This study focuses on the evaluation of the effect of hygrothermal conditioning on tensile, compressive, in-plane and interlaminar shear properties, and also on the viscoelastic characteristics of ...carbon fiber/epoxy laminates. Flat unidirectional laminates were manufactured by dry filament winding and cured under hot compression. The laminates were later exposed to hygrothermal conditioning in a chamber, following the recommendations of ASTM D5229M. All composite coupons were tested before and after conditioning. An analytical Fickian model was used to fit experimental data, showing very good estimates. Shear strength and modulus reduced to about 30 and 38 %, respectively. All specimens presented acceptable failure modes; shear specimens failed at the gage section with delaminations and fiber/matrix debonding, whereas short beam specimens failed via delaminations at the specimen mid-plane. Moisture penetration through the carbon/epoxy surface lead to interfacial debonding and matrix plasticization. Puck’s failure envelope accurately predicted failure under compressive and shear loading.
Abstract
Spatial arrangement of distinct Amazonian environments through time and its effect on specialized biota remain poorly known, fueling long-lasting debates about drivers of biotic ...diversification. We address the late Quaternary sediment deposition that assembled the world's largest seasonally flooded ecosystems. Genome sequencing was used to reconstruct the demographic history of bird species specialized in either early successional vegetation or mature floodplain forests. Sediment deposition that built seasonally flooded habitats accelerated throughout the Holocene (last 11,700 years) under sea level highstand and intensification of the South American Monsoon, at the same time as global increases in atmospheric methane concentration. Bird populations adapted to seasonally flooded habitats expanded due to enlargement of Amazonian river floodplains and archipelagos. Our findings suggest that the diversification of the biota specialized in seasonally flooded habitats is coupled to sedimentary budget changes of large rivers, which rely on combined effects of sea level and rainfall variations.
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•Functionalized cellulose nanocrystals (CNC) exhibit higher thermal stability.•Functionalization of CNC improves the dispersion and interaction with polymer matrix.•Good dispersion ...and interaction lead to nanocomposites with improved properties.
In this study, the effects of cellulose nanocrystals modified with octadecyl isocyanate on rheological, mechanical and degradation properties of nanocomposites based on poly (butylene adipate-co-terephthalate) (PBAT) were reported. Nanocomposites were prepared by melt mixing procedure of PBAT with 3, 5 and 7 wt% cellulose nanocrystals. The increase of PBAT-based nanocomposites mechanical strength was discussed as a function of the cellulose nanocrystals surface chemistry, and the optimal amount of nanofillers in the nanocomposites, whereas the biodegradation rate of the polymer was related to the cellulose nanocrystals hydrophobicity. The study here presented promotes further understanding of cellulose nanocrystals functionalization and its effect on the overall properties of polymeric nanocomposites.
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