Detection and discrimination between ochratoxin producer and non-producer strains of Penicillium nordicum on a ham-based medium using an electronic nose

The aim of this work was to evaluate the potential use of qualitative volatile patterns produced by Penicillium nordicum to discriminate between ochratoxin A (OTA) producers and non-producer strains on a ham-based medium. Experiments were carried out on a 3% ham medium at two water activities (aw ; 0.995, 0.95) inoculated with P. nordicum spores and incubated at 25°C for up to 14days. Growing colonies were sampled after 1, 2, 3, 7 and 14days, placed in 30-ml vials, sealed and the head space analysed using a hybrid sensor electronic nose device. The effect of environmental conditions on growth and OTA production was evaluated based on the qualitative response. However, after 7days, it was possible to discriminate between strains grown at 0.995 aw, and after 14days, the OTA producer and non-producer strain and the controls could be discriminated at both aw levels. This study suggests that volatile patterns produced by P. nordicum strains may differ and be used to predict the presence of toxigenic contaminants in ham. This approach could be utilised in ham production as part of a quality assurance system for preventing OTA contaminatio

Cooperative games and inclusion in physical education

De acuerdo con los principios teóricos de la praxeología motriz este estudio examinó cuatro tipos de conductas motrices cooperativas: ajustadas [AJUS], desajustadas [DESAJ], perversas [PER]) y de pacto (PACT) de 40 niños (18 con discapacidades and 22 sin discapacidades) de 8-11 años que participaron en un programa diseñado para promover la inclusión a través de juegos cooperativos. Las conductas motrices más frecuentes (24%) fueron las AJUS. Modelos de regresión múltiple mostraron que las variables dependientes tuvieron un considerable poder de explicación: AJUS, 34%; DESAJ, el 22%; PERV, 30% y 3% PACT. Con respecto a las variables independientes analizadas, es decir, la edad, el género y si la persona tenía discapacidad, sólo esta última explicó algunas de las conductas observadas.Based on the theoretical principles of motor praxeology this study examined four types of cooperative motor behaviours, namely well-matched [WMAT], mismatched [MISMAT], destructive [DEST] and cooperative agreement (PACT), among 40 children aged 8-11 years (18 children with disabilities and 22 without disabilities) who were taking part in a workshop designed to promote inclusion through cooperative games. The most commonly observed motor behaviour (24%) was WMAT. Multiple regression models showed that the dependent variables had considerable explanatory power: WMAT, 34%; MISMAT, 22%; DEST, 30%; and PACT 3%. With respect to the independent variables analysed, namely age, gender and whether or not the child had disabilities, only the latter explained some of the observed behaviour

Minimal set of generators of controllability space for singular linear dynamical systems

Due to the significant role played by singular systems in the form E ¿ x ( t ) = Ax ( t ) , on mathematical modeling of science and engineering problems; in the last years recent years its interest in the descriptive analysis of its structural and dynamic properties. However, much less effort has been devoted to studying the exact con- trollability by measuring the minimum set of controls needed to direct the entire system E ¿ x ( t ) = Ax ( t ) to any desired state. In this work, we focus the study on obtaining the set of all matrices B with a minimal number of columns, by making the singular system E ¿ x ( t ) = Ax ( t ) + Bu ( t ) controllable.Postprint (author's final draft

Accuracy control in Monte Carlo radiative calculations

The general accuracy law that rules the Monte Carlo, ray-tracing algorithms used commonly for the calculation of the radiative entities in the thermal analysis of spacecraft are presented. These entities involve transfer of radiative energy either from a single source to a target (e.g., the configuration factors). or from several sources to a target (e.g., the absorbed heat fluxes). In fact, the former is just a particular case of the latter. The accuracy model is later applied to the calculation of some specific radiative entities. Furthermore, some issues related to the implementation of such a model in a software tool are discussed. Although only the relative error is considered through the discussion, similar results can be derived for the absolute error

Thermal neutral format based on the step technology

The exchange of models is one of the most serious problems currently encountered in the practice of spacecraft thermal analysis. Essentially, the problem originates in the diversity of computing environments that are used across different sites, and the consequent proliferation of native tool formats. Furthermore, increasing pressure to reduce the development's life cycle time has originated a growing interest in the so-called spacecraft concurrent engineering. In this context, the realization of the interdependencies between different disciplines and the proper communication between them become critical issues. The use of a neutral format represents a step forward in addressing these problems. Such a means of communication is adopted by consensus. A neutral format is not directly tied to any specific tool and it is kept under stringent change control. Currently, most of the groups promoting exchange formats are contributing with their experience to STEP, the Standard for Exchange of Product Model Data, which is being developed under the auspices of the International Standards Organization (ISO 10303). This paper presents the different efforts made in Europe to provide the spacecraft thermal analysis community with a Thermal Neutral Format (TNF) based on STEP. Following an introduction with some background information, the paper presents the characteristics of the STEP standard. Later, the first efforts to produce a STEP Spacecraft Thermal Application Protocol are described. Finally, the paper presents the currently harmonized European activities that follow up and extend earlier work on the area

Synthèse des impacts écologiques des feux et des coupes forestières sur les lacs de l'écozone boréale au Québec

Cet article présente une première synthèse comparative des impacts des feux et des coupes forestières sur la qualité des eaux et les communautés aquatiques des lacs de l'écozone boréale de l'est du Canada. La recherche a été réalisée de 1996 à 1998 dans le cadre d'un projet du Réseau de centre d'excellence sur la gestion durable des forêts (RCE-GDF) et porte sur 38 lacs du Bouclier Canadien du Québec. Les changements dans la qualité de l'eau ainsi que dans la diversité, la biomasse et la structure des communautés de plancton et de poissons ont été suivis pendant trois ans dans 20 lacs dont les bassins versants étaient non perturbés, dans 9 lacs qui avaient subit des coupes forestières et dans 9 lacs qui avaient subit des feux de forêt.Notre étude montre que les feux et les coupes ont des impacts significatifs qui diffèrent selon le type de perturbation. En général, les lacs affectés par les coupes et les feux ont des concentrations de phosphore 2 à 3 fois plus élevées que les lacs de référence. Toutefois, les lacs affectés par les feux montrent des concentrations en nitrates beaucoup plus élevées tandis que les lacs affectés par les coupes sont moins transparents et ont des eaux plus colorées, très riches en carbone organique dissous. Les feux et les coupes affectent aussi de façon différente la minéralisation des eaux et les concentrations des ions majeurs. Les feux et les coupes n'ont pas d'effet sur la biodiversité des communautés planctoniques, sauf dans les lacs ayant un grand bassin versant et plus de 40 % de perturbation. Aucune différence n'a été observée entre les lacs de référence et les lacs perturbés au niveau de l'occurrence, l'abondance et la croissance des espèces de poissons. En revanche, les feux et les coupes affectent la production et la structure des communautés aquatiques. Dans les lacs affectés par les feux, l'enrichissement en azote et phosphore provoque une hausse de la concentration en chlorophylle a, et de la biomasse du phytoplancton et du limnoplancton (seston > 53 µm), en particulier des diatomées, des rotifères et des gros crustacés, pendant deux à trois années après les feux. En revanche, dans les lacs affectés par les coupes, l'enrichissement en phosphore n'entraîne qu'une augmentation très faible et limitée à un an de la biomasse des algues et pas de changement dans les biomasses du limnoplancton, en raison de la forte couleur et de la transparence réduite des eaux, qui limite la production biologique. Les coupes ont un impact négatif sur les copépodes calanoïdes, un groupe de zooplancton caractéristique des lacs oligotrophes et transparents. Une diminution significative de la proportion des individus de petite taille a été observée chez les populations de perchaude et de meunier noir des lacs perturbés (lacs de coupe et de feux formant un seul groupe). Les impacts observés dans la qualité des eaux et la production du plancton augmentent avec l'importance relative des perturbations au niveau du bassin versant. Cependant, la variabilité dans les caractéristiques des bassins versants et des lacs, en particulier le rapport de drainage et le temps de résidence des eaux, a des effets confondants sur les réponses des écosystèmes lacustres aux perturbations par les feux et les coupes.This paper presents a comparative review on ecological impacts of wildfires and harvesting on water quality and aquatic community attributes of boreal lakes in eastern Canada. This project was carried out from 1996 to 1998, as part of the research program of the Sustainable Forest Management Network Centre of Excellence (NCE-SFM), on 38 lakes of the Boreal Canadian Shield (Québec, Canada). Changes in water quality, and in diversity, biomass and community structure of pelagic plankton and fish populations were monitored for 3 years in 20 reference lakes, 9 cut lakes and 9 burnt lakes.Our study shows that wildfires and logging have significant impacts on water quality as well as primary and secondary producers in boreal lakes. However, fire and logging does not have similar impacts. In general, cut and burnt lakes showed higher concentrations of total phosphorus (TP: 2-3 folds) than reference lakes. However nitrates concentrations (NO3-) were higher in burnt lakes than in reference and cut lakes, whereas dissolved organic carbon (DOC), light extinction coefficient (e PAR) and water colour were higher in cut lakes than in reference lakes, burnt lakes showing intermediate values. Wildfire and logging also affect ionic composition of lake water. Both burnt and cut lakes had higher concentrations of potassium (K+), chloride (Cl-) and calcium (Ca2+) than reference lakes, while sulphates (SO42-) and magnesium (Mg2+) increased only in burnt lakes. The observed increases in organic and mineral elements reflect their export from the watershed and were related to the drainage ratio. As mobile ions are rapidly flushed from the perturbed watersheds, ionic water composition returned to normal levels within three years after the perturbation. In contrast, some changes in water quality (P and N enrichment in perturbed lakes; DOC increase in cut lakes) seems to be on longer term and might have a more important effect on limnological features of lakes such as thermal stratification, mixed and euphotic depth, plankton biomass and bioaccumulation of mercury in zooplankton and fish.Wildfires and logging do not have significant impacts on species richness of planktonic communities, except for lakes with large drainage basins and those where the perturbation was higher than 40% of the watershed area. However, wildfires and logging affect biomass of plankton communities. In burnt lakes, the nutrient enrichment induced important increases in Chl. a concentration and phytoplankton biomass, and a small increase in limnoplankton biomass (seston > 53 µm). Diatoms, rotifers and large crustaceans showed significant increases. In burnt lakes, increases in phytoplankton were observed during the three years of the survey and were highest in the first 2 years after fires. Limnoplankton increases lasted only 2 years and were highest the second year after fires. In cut lakes, nutrient enrichment was not reflected in a proportional increase in plankton production due to increase in DOC concentrations and lake water colour that reduced water transparency. Phytoplankton slightly increased only the first year after logging and no increase was observed for limnoplankton and zooplankton. Logging negatively affect calanoids, a zooplankton group characteristic of clear and oligotrophic lakes. No significant differences were observed in the occurrence, abundance and growth of fish populations among reference and perturbed lakes. However, the proportion of small yellow perch and white sucker were significantly lower in populations of impacted lakes (burned and logged lakes pooled). In most cases, impacts on water quality and plankton communities were related to the intensity of fire or logging, when expressed as the percent area of watershed harvested or burnt divided by the lake surface or volume. Simple models may then be developed and help to predict the effect of harvesting practices on lake ecosystems. However, environmental variation in watershed and lakes characteristics, especially drainage ratio and lake water residence time, are important confounding factors in the responses of lakes to watershed perturbations by fire or logging. Lakes with drainage ratio > 4 and with more of 30% of their watershed perturbed are the most sensitive to fire and logging. These factors should be considered when developing lake management models in the boreal forest impacted by fire and logging

Immunology: Investigations on the cell type responsible for the endometrial secretion of complement component 3 (C3)

It has been shown that and human endometria have the capacity to produce complement component 3 (C3). In rats, endometrial C3 is an oestrogen-dependent protein produced and secreted by glandular cells. The cell responsible for the synthesis and secretion of human endometrial C3 has not been clearly defined. Our study was aimed at answering this question. Samples of endometrium obtained from hysterectomies were either immunostained for C3 or digested with collagenase; then the stromal and glandular cells were separated and immunopurified (or not) with an antibody to CD45 coupled to magnetic beads to eliminate the endometrial lymphomyeloid cells. Cells were cultured for 2 weeks and C3 measured in the medium by an in-house radioimmunoassay. Glandular as well as stromal cells stained positively for C3 and released C3 in vitro. The release of C3 from both cell types could be inhibited by cycloheximide. Epithelial cells produced significantly more C3 than stromal cells, and endometrial C3 production was higher for both cell types when these were obtained from secretory as compared to proliferative endometria. Lymphomyeloid cells were possibly a source of C3 since after immunoadsorption of these cells, the remaining stromal or glandular cells produced significantly less C3. We conclude that endometrial stromal, glandular and lymphomyeloid cells all produce C

Seahorse aquaculture, biology and conservation: knowledge gaps and research opportunities

11 páginas, 6 figuras, 1 tablaSeahorses are currently experiencing an unprecedented level of anthropogenic pressure promoted by habitat destruction and increasing fishing effort to supply premium markets. This study provides an overview of the scientific literature on seahorses in the 21st century and critically discusses five major knowledge gaps and research opportunities to advance the state of the art on this research field. The average number of publications per year increased from 10 (2001–2002) to ∼40 (2001–2015), the majority addressing issues on seahorse ecology, biology, and aquaculture, with the most studied species being Hippocampus kuda, H. guttulatus, H. reidi, H. abdominalis, H. erectus, H. hippocampus, and H. trimaculatus. This study explores the opportunity of using seahorses as flagship species to foster mangrove conservation and decrease trawling fisheries. It also suggests that further scientific studies are needed to better understand and manage the populations of the most heavily traded seahorse species, as well as the need to monitor their vulnerability to emerging pollutants and climate change. Sustainable seahorse aquaculture can play an important role in seahorse conservation, as well as in the development of reliable traceability tools to fight the illegal trade of these highly priced organismsWe thank the São Paulo Research Foundation–FAPESP (grants nos. 2013/22260-6 and 2015/18050-0) and The National Council for Scientific and Technological Development–CNPq (grant nos. 441356/2014-1) for the financial support provided. Thanks also to FCT/MEC through national funds, and the cofunding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020 for the financial support to CESAM (UID/AMB/50017/2013)Peer reviewe

Functional output-controllability of time-invariant singular linear systems

In the space of finite-dimensional singular linear continuous-time-invariant systems described in the form \begin{equation}\label{eq1}\left . \begin{array}{rl} E \dot x(t)&= Ax(t)+Bu(t)\\ y(t)&=Cx(t)\end{array}{\kern-1mm}\right \}\end{equation} where $E,A\in M=M_{n}(\mathbb{C})$, $B\in M_{n\times m}(\mathbb{C})$, $C\in M_{p\times n}(\mathbb{C})$, functional output-controllability character is considered. A simple test based in the computation of the rank of a certain constant matrix that can be associated to the system is presentedPeer ReviewedPostprint (published version

HIV-1 selectively targets gut-homing CCR6+CD4+ T cells via mTOR-dependent mechanisms

Gut-associated lymphoid tissues are enriched in CCR6+ Th17-polarized CD4+ T cells that contribute to HIV-1 persistence during antiretroviral therapy (ART). This raises the need for Th17-targeted immunotherapies. In an effort to identify mechanisms governing HIV-1 permissiveness/persistence in gut-homing Th17 cells, we analyzed the transcriptome of CCR6+ versus CCR6- T cells exposed to the gut-homing inducer retinoic acid (RA) and performed functional validations in colon biopsies of HIV-infected individuals receiving ART (HIV+ART). Although both CCR6+ and CCR6- T cells acquired gut-homing markers upon RA exposure, the modulation of unique sets of genes coincided with preferential HIV-1 replication in RA-treated CCR6+ T cells. This molecular signature included the upregulation of HIV-dependency factors acting at entry/postentry levels, such as the CCR5 and PI3K/Akt/mTORC1 signaling pathways. Of note, mTOR expression/phosphorylation was distinctively induced by RA in CCR6+ T cells. Consistently, mTOR inhibitors counteracted the effect of RA on HIV replication in vitro and viral reactivation in CD4+ T cells from HIV+ART individuals via postentry mechanisms independent of CCR5. Finally, CCR6+ versus CCR6- T cells infiltrating the colons of HIV+ART individuals expressed unique molecular signatures, including higher levels of CCR5, integrin β7, and mTOR phosphorylation. Together, our results identify mTOR as a druggable key regulator of HIV permissiveness in gut-homing CCR6+ T cells