Natural fiber is a resource that is found abundantly and cost effective. It is decomposed easily and biodegradable. Natural fibers have a vital place in the industry and have the capability of ...replacing carbon fibers and conventional glass because of their biodegradability and eco-friendly characteristics. They have significant chemical, mechanical, and physical properties, which vary according to cellulose content in the fiber. Usually, with the increase in the cellulose content, the tensile strength of the fiber increases and with the increase in the non-cellulose content, the tensile strength of the fiber decreases. However, these chemical constituents are not the only factors that determine the tensile strength of the fiber. Certain other factors such as fiber age, maturity, location, and processing methods along with the source of the fiber also influence the tensile strength of the fiber. These properties of the natural fibers make it a vital component in engineering applications. Natural fibers meet the needs of humans and the manufacturing industry with their positive environmental effect and economic outlook. This review provides basic information and a segregated study on the mechanical properties of natural fibers, thus creating opportunities for future research and studies related to natural fiber-reinforced composites.
Trace metals are stored in near-channel floodplain sediments along many rivers in industrial and mined watersheds of western European countries such as Germany. In this paper, I document the ...distribution of Cu, Pb, and Zn in 13 cores collected from near-channel floodplain sediments along a 25-km reach of the Dill River in central Germany. Mean concentrations of the three trace metals exceed background concentrations, an indication of anthropogenic enrichment along the study reach; many individual samples have concentrations several times the background levels and exceed standards for trace metals contained in the German Federal Soil Protection Act. Metal concentrations generally peak at depths of 0.2 to 0.7m below the floodplain surface and are assumed to represent the period of maximum metal releases to the environment through upstream industrial activity, ore mining, or both. In eight of the cores, radiocarbon ages obtained below the depth of peak metal concentrations provide maximum dates for sediment accumulation of between 90 and 1700years ago, with most ages clustering in the period of 90 to 300years ago. The ages and depth to peak metal concentrations indicate 0.6 to 1.0m of floodplain sedimentation over the last 150 to 300years (0.3–0.4cmy−1), which exceed sedimentation amounts and rates found in surrounding watersheds. Surface sediments contain lower metal concentrations, suggesting deposition recently of cleaner sediments. Trace metals stored along the Dill River serve as a reminder that stores of contaminants exist in geomorphically sensitive locations of the fluvial system. These legacy sediments bear the chemical imprint of industrial or mining activities that no longer occur in the watershed.
•Trace metal concentrations exceed non-anthropogenic concentrations.•Trace metal concentrations peak at depths of 0.20–0.70m.•Peak concentrations correspond to maximum metal releases upstream.•Rapid floodplain sedimentation over last 150 to 200year.•Stored trace metals are potential source of future downstream contamination.
Purpose
This paper aims to revisit Martin and Pranter’s (1989) Journal of Services Marketing article, “Compatibility Management …”, and by doing so, heighten service scholars’ and practitioners’ ...awareness of the historical and ongoing relevance of customer-to-customer (C2C) encounters, the challenges C2C encounters pose and the opportunities for future research.
Design/methodology/approach
A combination of review and commentary approaches is taken to summarize the 1989 article, the circumstances of its conception, the topic’s intersection with contemporary service topics and to illustrate the multi-faceted nature of C2C encounters and the challenges faced in their management.
Findings
Investigated in a number of service contexts, C2C encounters continue to be relevant in a multitude of service environments where customers converge.
Research limitations/implications
Because the evolution of service scholarship and practice is collectively shaped by an infinite number of people, events and sources, the attribution of effects to only one or a few influences is a highly subjective matter of interpretation.
Practical implications
Because C2C encounters are part of customers’ service experiences and can affect their satisfaction and patronage behaviors, service organizations can benefit by their efforts to influence C2C encounters.
Social implications
The criteria customers use to react to other customers and the bases used by service organizations/personnel to manage C2C encounters may not always be morally, ethically or legally defensible. For example, the Napa Valley Wine Train incident of 2015 involved allegations of racial discrimination and intentional infliction of emotional distress.
Originality/value
The retrospective analysis contributes to the field’s understanding of the historical development of services marketing and provides fodder for future research.
Porous membranes are used in chemical separations and in many electrochemical processes and devices. Research on the transport properties of a unique class of porous membranes that contain ...monodisperse gold nanotubes traversing the entire membrane thickness is reviewed here. These gold nanotubes can act as conduits for ionic and molecular transports through the membrane. Because the tubes are electronically conductive, they can be electrochemically charged by applying a voltage to the membrane. How this “voltage charging” affects the transport properties of gold nanotube membranes is the subject of this Review. Experiments showing that voltage charging can be used to reversibly switch the membrane between ideally cation‐ and anion‐transporting states are reviewed. Voltage charging can also be used to enhance the ionic conductivity of gold nanotube membranes. Finally, voltage charging to accomplish electroporation of living bacteria as they pass through gold nanotube membranes is reviewed.
Research on the transport properties of porous membranes containing gold nanotubes traversing the membrane thickness is reviewed here. Because the tubes are electronically conductive, they can be electrochemically charged by applying a voltage to the membrane. How this “voltage charging” affects the transport of ions and molecules through these gold nanotube conduits is the subject of this Review.
There are many applications that require the integration of a pump and a chemical sensor so that the solution being pumped can be analyzed in real time for a specific chemical species and the flow ...adjusted according to the measured concentration of that species. We describe here an alternative strategy: a chemoresponsive pump where a single device acts as both the sensor and pump simultaneously. We demonstrate this concept with a nanofluidic Pb2+-responsive pump that uses electroosmotic flow as the pumping technology, and a Pb2+-binding ionophore that allows the device to selectively respond to Pb2+. The pump yields high flow rates at low Pb2+ concentrations (<1 μM), but flow rate decreases with concentrations above this threshold and ultimately goes to zero at concentrations above 100 μM.
Sound production in fishes is vital to an array of behaviors including territorial defense, reproduction, and competitive feeding. Unfortunately, recent passive acoustic monitoring efforts are ...revealing the extent to which anthropogenic forces are altering aquatic soundscapes. Despite the importance of fish sounds, extensive endeavors to document them, and the anthropogenic threats they face, the field of fish bioacoustics has been historically constrained by the lack of an easily accessible and comprehensive inventory of known soniferous fishes, as is available for other taxa. To create such an inventory while simultaneously assessing the geographic and taxonomic prevalence of soniferous fish diversity, we extracted information from 834 references from the years 1874–2020 to determine that 989 fish species from 133 families and 33 orders have been shown to produce active (i.e., intentional) sounds. Active fish sound production is geographically and taxonomically widespread—though not homogenous—among fishes, contributing a cacophony of biological sounds to the prevailing soundscape globally. Our inventory supports previous findings on the prevalence of actively soniferous fishes, while allowing novel species-level assessments of their distribution among regions and taxa. Furthermore, we evaluate commercial and management applications with passive acoustic monitoring, highlight the underrepresentation of research on passive (i.e., incidental) fish sounds in the literature, and quantify the limitations of current methodologies employed to examine fishes for sound production. Collectively, our review expands on previous studies while providing the foundation needed to examine the 96% of fish species that still lack published examinations of sound production.
Abstract
Scope: Adipocyte‐derived extracellular vesicles (AdEVs) convey lipids that can play a role in the energy homeostasis. Vitamin D (VD) has been shown to limit the metabolic inflammation as it ...decreases inflammatory markers expression in adipose tissue (AT). However, VD effect on adipocytes‐derived EVs has never been investigated.
Methods and results: Thus, the aim of this study is to evaluate the AdEVs lipid composition by LC‐MS/MS approach in 3T3‐L1 cells treated with VD or/and pro‐inflammatory factor (tumor necrosis factor α TNFα). Among all lipid species, four are highlighted (glycerolipids, phospholipids, lysophospholipids, and sphingolipids) with a differential content between small (sEVs) and large EVs (lEVs). This study also observes that VD alone modulates EV lipid species involved in membrane fluidity and in the budding of membrane. EVs treated with VD under inflammatory conditions have different lipid profiles than the control group, which is more pronounced in lEVs. Indeed, 25 lipid species are significantly modulated in lEVs, compared with only seven lipid species in sEVs.
Conclusions: This study concludes that VD, alone or under inflammatory conditions, is associated with specific lipidomic signature of sEVs and lEVs. These observations reinforce current knowledge on the anti‐inflammatory effect of VD.
Scope
Vitamin D deficiency (VDD) is becoming a global issue and low 25‐hydroxyvitamin D (25(OH)D) plasma levels have been linked to hepatic steatosis in adulthood. Nevertheless, the impact of ...maternal VDD on lipid metabolism and hepatic steatosis remains poorly documented, especially under obesogenic condition. The goal of this study is to assess the effects of maternal VDD on hepatic lipid accumulation in adult offspring fed a normal or obesogenic diet.
Methods and results
Several approaches are implemented including histology and lipidomics on the liver in both males and females. No major impact of high‐fat (HF) or VDD is observed at histological level in both males and females. Nevertheless, in males born from VDD mice and fed an HF diet, an increase of total lipids and modulation of the relative lipid species distribution characterized by a decrease of triglycerides and increase of phospholipids is observed. In female no major lipid profile is noticed.
Conclusion
Maternal VDD combined with a HF diet in male may predispose to hepatic hypertrophia, with a specific lipid profile. Such observations reinforce our knowledge of the impact of maternal VDD on hepatic programming in the offspring.
The goal of this study is to assess the effects of maternal VDD on hepatic lipid accumulation in adult offspring fed a normal or obesogenic diet. This study demonstrates that maternal VDD combined with a high‐fat diet in male may predispose to hepatic lipid accumulation, with a specific lipid profile, whereas no major modification is observed in females.
Robots are traditionally bound by a fixed morphology during their operational lifetime, which is limited to adapting only their control strategies. Here we present the first quadrupedal robot that ...can morphologically adapt to different environmental conditions in outdoor, unstructured environments. Our solution is rooted in embodied AI and comprises two components: (1) a robot that permits in situ morphological adaptation and (2) an adaptation algorithm that transitions between the most energy-efficient morphologies on the basis of the currently sensed terrain. We first build a model that describes how the robot morphology affects performance on selected terrains. We then test continuous adaptation on realistic outdoor terrain while allowing the robot to constantly update its model. We show that the robot exploits its training to effectively transition between different morphological configurations, exhibiting substantial performance improvements over a non-adaptive approach. The demonstrated benefits of real-world morphological adaptation demonstrate the potential for a new embodied way of incorporating adaptation into future robotic designs.The morphology of a robot determines how efficiently it can traverse different terrain. Nygaard and colleagues present here a robot that can adapt it’s morphology when it is detecting different terrain and learn which configuration is most effective.
Prebiotic fibres like short-chain fructo-oligosaccharides (scFOS) are known to selectively modulate the composition of the intestinal microbiota and especially to stimulate Bifidobacteria. In ...parallel, the involvement of intestinal microbiota in host metabolic regulation has been recently highlighted. The objective of the study was to evaluate the effect of scFOS on the composition of the faecal microbiota and on metabolic parameters in an animal model of diet-induced obesity harbouring a human-type microbiota. Forty eight axenic C57BL/6J mice were inoculated with a sample of faecal human microbiota and randomly assigned to one of 3 diets for 7 weeks: a control diet, a high fat diet (HF, 60% of energy derived from fat)) or an isocaloric HF diet containing 10% of scFOS (HF-scFOS). Mice fed with the two HF gained at least 21% more weight than mice from the control group. Addition of scFOS partially abolished the deposition of fat mass but significantly increased the weight of the caecum. The analysis of the taxonomic composition of the faecal microbiota by FISH technique revealed that the addition of scFOS induced a significant increase of faecal Bifidobacteria and the Clostridium coccoides group whereas it decreased the Clostridium leptum group. In addition to modifying the composition of the faecal microbiota, scFOS most prominently affected the faecal metabolome (e.g. bile acids derivatives, hydroxyl monoenoic fatty acids) as well as urine, plasma hydrophilic and plasma lipid metabolomes. The increase in C. coccoides and the decrease in C. leptum, were highly correlated to these metabolic changes, including insulinaemia, as well as to the weight of the caecum (empty and full) but not the increase in Bifidobacteria. In conclusion scFOS induce profound metabolic changes by modulating the composition and the activity of the intestinal microbiota, that may partly explain their effect on the reduction of insulinaemia.
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