Microalgal symbiosis in biotechnology

This review provides an analysis of recent published work on interactions between microorganisms, especially the ones involving mainly nutrient exchanges and at least with one microalga species. Examples of microbial partners are given, with a remark to the potential application of cultures of an autotroph and a heterotroph, which grow simultaneously, taking advantage of the complementary metabolisms. These are particularly interesting, either due to economic or sustainable aspects, and some applications have already reached the commercial stage of development. The added advantages of these symbiotic cultures are biomass, lipid, and other products productivity enhancement a better utilization of resources and the reduction or even elimination of process residues (including carbon dioxide and other greenhouse gases) to conduct an increasingly greener biotechnology. Among the several symbiotic partners referred, the microalgae and yeast cultures are the most used. The interaction between these two microorganisms shows how to enhance the lipid production for biodiesel purposes compared with separated (stand-alone) cultures

Using Consumer Behavior Scales to Examine the Persuasiveness of Travel Narratives

Currently, an understanding of how travelers process promotional travel-related narratives or information sources is lacking in tourism literature. Moreover, when examined in the context of tourism, promotional narratives have been largely examined by literary and history scholars from a more critical standpoint where, in short, conclusions often assume the narratives examined possess a certain level of persuasive power. As such, the purpose of this exploratory study was to examine the general persuasive power of travel narratives. To do so, the study incorporated two consumer behavior scales, Green and Brock’s (2000) Transportation scale, as well as Obermiller and Spangenberg’s (1988) Skepticism Toward Advertising scale (SKEP), to measure individuals processing of travel narratives, as well as their perceived level of skepticism towards travel narratives presented in two different formats—travel articles and travel brochures. The utilization of these consumer behavior scales allowed for an examination of the degree to which presentation format, message cue, skepticism towards travel articles, and skepticism towards travel brochures influenced participants’ narrative transportation. Additionally, the relationship between participants’ skepticism towards travel articles and travel brochures was examined

Preface of the "Symposium on dynamical systems applied to robotics"

[Excerpt] Robotics has been evolving in last years, considering the different fields that can be tackled. This is an important and diversified domain, which is normally solved using bio-inspired or model-based approaches. In this symposia, we focus on the use of the dynamical systems theory to address any related problems in the robotics domain. Dynamical systems exhibit some properties which makes them well suited to real-time robotic applications, such as movement generation for legged; modular and wheeled platforms; balance control; grasping; reaching, etc. [...](undefined

Influence of Gender and Age on the Processing of Travel Narratives

The purpose of this study was to investigate processing as well as perceived skepticism towards tourism persuasive communications. The importance of understanding processing and perceived skepticism resides in the fact that both have been linked to overall message persuasiveness; and as such, both are essential to developing and implementing effective travel promotional communications. Moreover, extant research suggests that general persuasability may differ depending upon such demographic characteristics as gender and age. Therefore, this study sought to examine if participants differed based on their demographic characteristics—gender and age—in (1) the degree to which participants’ were able to be transported by a narrative (i.e. process), and (2) participants’ level of perceived skepticism concerning travel articles and travel brochures. Overall, data analysis revealed several significant findings, indicating that age had a significant influence on participants’ skepticism towards travel articles and participants’ skepticism towards travel brochures. Additionally, gender was shown to have a significant influence on participants’ degree of narrative transportation

Human dermal exposure to galaxolide from personal care products

Musks are synthetic fragrances applied on personal care and household products as fixatives, by retarding the release of other fragrances with higher volatility. Galaxolide is the most used polycyclic musk since the 90th decade, and it has been detected in several environmental and biological matrices, particularly in human tissues and fluids. For exposure assessment purposes, large-monitoring data need to be obtained and rapid but reliable analytical techniques are requested. The main objective of this study is to develop and validate a new and fast analytical methodology to quantify galaxolide in personal care products and to apply this method to real matrices like skin care products (creams and lotions), shower products (soap bar), hair care products (shampoo and hair conditioner) and oral care products (toothpaste), to evaluate the human dermal exposure risk. A dispersive solid-phase extraction is proposed, using QuEChERS methodology, followed by HPLC with fluorescence detection. Some extraction parameters were studied, like the ratio of sample/solvent amounts, the homogenization time, the salt addition effect and the used sorbents. The validation parameters of the developed method were the following: a linearity range of 0.005-1.002 mg kg⁻¹ sample, a limit of detection of 0.001 mg kg⁻¹ sample, repeatability between 0.7% and 11.3% (variation coefficient of six standard injections), an intermediate precision of 2.5% (variation coefficient of six independent analysis of the same sample), mean recoveries ranging from 65% (soap bar) to 95% (body cream) and 3% of global uncertainty in most of the working range. The time of analysis, including the extraction steps, is 60 min, allowing a throughput of 4 samples h⁻¹ . Galaxolide was detected in all of the seven analysed products in concentrations ranging from 0.04 ± 0.01 mg kg⁻¹ sample (toothpaste) to 280.78 ± 8.19 mg kg⁻¹ sample (perfumed body cream), which may correspond to a significant estimated daily human dermal exposure of 904 μg day⁻¹.info:eu-repo/semantics/publishedVersio

potential strategy for assessing health care policies

© The Author(s) 2020. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.BACKGROUND: Tuberculosis (TB) causes pressure on healthcare resources, especially in terms of hospital admissions, despite being considered an ambulatory care-sensitive condition for which timely and effective care in ambulatory setting could prevent the need for hospitalization. Our objectives were to describe the spatial and temporal variation in pulmonary tuberculosis (PTB) hospitalizations, identify critical geographic areas at municipality level and characterize clusters of PTB hospitalizations to help the development of tailored disease management strategies that could improve TB control. METHODS: Ecologic study using sociodemographic, geographical and clinical information of PTB hospitalization cases from continental Portuguese public hospitals, between 2002 and 2016. Descriptive statistics, spatiotemporal cluster analysis and temporal trends were conducted. RESULTS: The space-time analysis identified five clusters of higher rates of PTB hospitalizations (2002-16), including the two major cities in the country (Lisboa and Porto). Globally, we observed a -7.2% mean annual percentage change in rate with only one of the identified clusters (out of six) with a positive trend (+4.34%). In the more recent period (2011-16) was obtained a mean annual percentage change in rate of -8.12% with only one cluster identified with an increase trend (+9.53%). CONCLUSIONS: Our results show that space-time clustering and temporal trends analysis can be an invaluable resource to monitor the dynamic of the disease and contribute to the design of more effective, focused interventions. Interventions such as enhancing the detection of active and latent infection, improving monitoring and evaluation of treatment outcomes or adjusting the network of healthcare providers should be tailored to the specific needs of the critical areas identified.publishersversionpublishe

A brainstem-like modulation approach for gait transition in a quadruped robot

The ability to traverse a wide variety of terrains while walking is basically a requirement for performing useful tasks in our human centric world. In this article, we propose a bio-inspired robotic controller able to generate locomotion and to easily switch between different type of gaits. In order to improve the robot stability and response while locomoting, we adjust both the duty factor and the interlimb phase relationships, according to the velocities. We extend previous work, by applying nonlinear oscillators to generate the rhythmic locomotor movements for a quadruped robot, similarly to the biological counterparts. The generated trajectories are modulated by a drive signal, that modifies the oscillator frequency, amplitude and the coupling parameters among the oscillators, proportionally to the drive signal strength. By increasing the drive signal, locomotion can be elicited and velocity increased while switching to the appropriate gaits. This drive signal can be specified according to sensory information or set a priori. The implementation of the central pattern generator network and the activity modulation layer is shown in simulation and in an AIBO robot

Identification and characterisation of xylanolytic yeasts isolated from decaying wood and sugarcane bagasse in Brazil

In this study, yeasts associated with lignocellulosic materials in Brazil, including decaying wood and sugarcane bagasse, were isolated, and their ability to produce xylanolytic enzymes was investigated. A total of 358 yeast isolates were obtained, with 198 strains isolated from decaying wood and 160 strains isolated from decaying sugarcane bagasse samples. Seventy-five isolates possessed xylanase activity in solid medium and were identified as belonging to nine species: Candida intermedia, C. tropicalis, Meyerozyma guilliermondii, Scheffersomyces shehatae, Sugiyamaella smithiae, Cryptococcus diffluens, Cr. heveanensis, Cr. laurentii and Trichosporon mycotoxinivorans. Twenty-one isolates were further screened for total xylanase activity in liquid medium with xylan, and five xylanolytic yeasts were selected for further characterization, which included quantitative analysis of growth in xylan and xylose and xylanase and ß-d-xylosidase activities. The yeasts showing the highest growth rate and cell density in xylan, Cr. laurentii UFMG-HB-48, Su. smithiae UFMG-HM-80.1 and Sc. shehatae UFMG-HM-9.1a, were, simultaneously, those exhibiting higher xylanase activity. Xylan induced the highest level of (extracellular) xylanase activity in Cr. laurentii UFMG-HB-48 and the highest level of (intracellular, extracellular and membrane-associated) ß-d-xylosidase activity in Su. smithiae UFMG-HM-80.1. Also, significant ß-d-xylosidase levels were detected in xylan-induced cultures of Cr. laurentii UFMG-HB-48 and Sc. shehatae UFMG-HM-9.1a, mainly in extracellular and intracellular spaces, respectively. Under xylose induction, Cr. laurentii UFMG-HB-48 showed the highest intracellular ß-d-xylosidase activity among all the yeast tested. C. tropicalis UFMG-HB 93a showed its higher (intracellular) ß-d-xylosidase activity under xylose induction and higher at 30 °C than at 50 °C. This study revealed different xylanolytic abilities and strategies in yeasts to metabolise xylan and/or its hydrolysis products (xylo-oligosaccharides and xylose). Xylanolytic yeasts are able to secrete xylanolytic enzymes mainly when induced by xylan and present different strategies (intra- and/or extracellular hydrolysis) for the metabolism of xylo-oligosaccharides. Some of the unique xylanolytic traits identified here should be further explored for their applicability in specific biotechnological processes

Anaerobic Digestion of Microalga Chlorella protothecoides and Metagenomic Analysis of Reddish-Colored Digestate

ABSTRACT: Microalga Chlorella protothecoides materials were assessed as substrates for anaerobic digestion (AD) aiming at the simultaneous production of biogas/methane and pigments: whole autotrophic (AA) and heterotrophic algae (H); extracted heterotrophic microalgae from lipid production (HExt); and pretreated heterotrophic microalgae through enzymatic (HPEnz), autoclave (HPA), and ultrasound (HPU) processes. AA was more suitable for AD than H, as it was more efficiently converted into methane (279 vs. 180 L CH4/kg VSin). In comparison, the pretreatment of heterotrophic microalgae had a positive effect on AD, with registered methane yield increases from 263 to 290 L CH4/kg VSin (HPU, HPA, HExt). Reddish pigmentation developed in H and HPU units due to the presence of purple non-sulfur bacteria (PNSB). This phenomenon and the changes in microbiota structure during AD were confirmed by metagenomic analysis. At the end of the process, the relative abundance of Clostridiales and Bacillales increased, enhancing the hydrolysis of compounds in acetate. Consistently, Methanosaeta became the comparatively dominant methanogen, meaning that methane was produced through the acetoclastic methanogenesis pathway. The obtained results indicate for AD biorefinery feasibility-regarding the simultaneous production of biogas/methane-a digestate flow and pigments (bacteriochlorophyll a and carotenoids).info:eu-repo/semantics/publishedVersio

Associations between emotion regulation, feeding practices, and preschoolers’ food consumption

: Previous research identified emotion dysregulation, non-responsive feeding practices, and unhealthy food consumption as risk factors for childhood obesity. However, little is known about the relationships between these factors. This study examined associations between children’s emotion regulation, parental feeding practices, and children’s food consumption. The sample consisted of 163 mothers of children aged 3–5 years. Mothers completed the Emotion Regulation Checklist, the Child Feeding Questionnaire, and the Child Health Section from the Parent Interview of the Early Childhood Longitudinal Study-B to assess model variables. Results showed that healthy food consumption was associated with higher emotion regulation abilities, higher monitoring, and lower pressure to eat. For unhealthy food consumption, the associations were in opposite directions. Higher emotion regulation abilities were also associated with higher monitoring, lower pressure to eat, and lower restriction. For lability, the associations were in opposite directions. Regression analyses revealed that children’s lability, pressure to eat, and monitoring were significant predictors of children’s food consumption. These findings suggest that children’s emotion regulation and feeding practices are important determinants of children’s food consumption. Future longitudinal studies that examine bidirectional associations between children’s emotion regulation, parental feeding practices, children’s food consumption, and potential mechanisms accounting for these associations are needed.info:eu-repo/semantics/publishedVersio