Spatial and temporal organization of a coastal lagoon fish community: Ria de Aveiro, Portugal

The fish community and its spatial and temporal organization were studied in the Ria de Aveiro. This lagoon system (43 km2 in area), has both marine and fluvial influences and is located between 40º 30’ - 40º 52’N and 8º35’ - 8º 47’W on the central coast of Portugal. The ichthyofauna was sampled monthly, from December 1996 to November 1997, at nine selected stations, with “chincha”, a traditionally-used beach-seine-type net of the region. A total of 14,598 specimens representing 43 species from 21 families were caught. The abiotic parameters (temperature, salinity and dissolved oxygen) showed significant seasonal variations, although only salinity and transparency showed statistically significant trends among sampling stations. The diversity and evenness were greater at the borders of the lagoon. The species richness, diversity and evenness peaked in mid-Summer. Marine seasonal migrant species were the most numerous, and the marine juvenile and estuarine resident categories had the highest number of species. Species number and diversity of the ecological guilds showed some spatio-temporal patterns due to some particular dominant species. Mugilidae, Atherinidae, Moronidae and Clupeidae were the most abundant families. Six species were dominant and represented more than 74% of the total fish abundance, although they did not occur over the whole lagoon area or during the whole sampling period. The study concludes that the fish community of the Ria de Aveiro has well-defined seasonal and spatial patterns.Organis ation spatiale et temporelle de la communauté de poissons d’une lagune côtière – Ria de Aveiro, Portugal. La communauté de poissons et son organisation spatiale et temporelle ont été étudiées dans la Ria de Aveiro. Ce système de lagune (43 km2 de superficie) subit des influences maritimes et fluviales et est situé entre 40º 30’ - 40º 52’N et 8º35’ - 8º 47’W sur la côte centrale du Portugal. Des échantillons ont été prélevés mensuellement de décembre 1996 à novembre 1997, dans neuf stations, avec un filet de pêche traditionnel de la région, la “chincha”. Au total 14 2 598 spécimens ont été collectés représentant 43 espèces et 21 familles. Les paramètres abiotiques (température, salinité et oxygène dissou) ont montré des variations saisonnières significatives, tandis que sur l’ensemble des stations de prélèvement seules la salinité et la transparence ont présenté une variation significative. La diversité et l’équatibilité ont été maximales le long des rives de la lagune. La richesse en espèces, diversité et équatibilité ont leur maximum été. Les espèces marines étaient les plus nombreuses et les catégories “juvénile marin” et “résident estuarien” sont celles qui avaient le plus grand nombre d’espèces. Le nombre d’espèces et la diversité des catégories écologiques ont montré des patterns liés à certaines espèces dominantes. Mugilidae, Atherinidae, Moronidae et Clupeidae étaient les familles les plus abondantes. Six espèces dominaient, même si elles n’étaient pas présentes sur toute la superficie de la lagune ou durant toute la période des échantillons, représentant plus de 74% du total de l’abondance en poisson. Cette étude permet de conclure que la communauté de poisson de la Ria de Aveiro a des patrons saisonniers et spatiaux très bien définis

Serine 58 of 14-3-3ζ Is a molecular switch regulating ASK1 and oxidant stress-induced cell death

Oxidant stress is a ubiquitous stressor with negative impacts on multiple cell types. ASK1 is a central mediator of oxidant injury, but while mechanisms of its inhibition, such as sequestration by 14-3-3 proteins and thioredoxin, have been identified, mechanisms of activation have remained obscure and the signaling pathways regulating this are not clear. Here, we report that phosphorylation of 14-3-3ζ at serine 58 (S58) is dynamically regulated in the cell and that the phosphorylation status of S58 is a critical factor regulating oxidant stress-induced cell death. Phosphorylation of S58 releases ASK1 from 14-3-3ζ, and ASK1 then activates stress-activated protein kinases, leading to cell death. While several members of the mammalian sterile 20 (Mst) family of kinases can phosphorylate S58 when overexpressed, we identify Ste20/oxidant stress response kinase 1 (SOK-1), an Mst family member known to be activated by oxidant stress, as a central endogenous regulator of S58 phosphorylation and thereby of ASK1-mediated cell death. Our findings identify a novel pathway that regulates ASK1 activation and oxidant stress-induced cell death

Review engagements -- new and expanded guidance on analytical procedures, inquiries, and other procedures

https://egrove.olemiss.edu/aicpa_guides/1278/thumbnail.jp

Review engagements -- new and expanded guidance on analytical procedures, inquiries, and other procedures

https://egrove.olemiss.edu/aicpa_comm/1200/thumbnail.jp

A study on wear evaluation of railway wheels based on multibody dynamics and wear computation

The wear evolution of railway wheels is a very important issue in railway engineering. In the past, the reprofiling intervals of railway vehicle steel wheels have been scheduled according to designers' experience. Today, more reliable and accurate tools in predicting wheel wear evolution and wheelset lifetime can be used in order to achieve economical and safety benefits. In this work, a computational tool that is able to predict the evolution of the wheel profiles for a given railway system, as a function of the distance run, is presented. The strategy adopted consists of using a commercial multibody software to study the railway dynamic problem and a purpose-built code for managing its pre- and post-processing data in order to compute the wear. The tool is applied here to realistic operation scenarios in order to assess the effect of some service conditions on the wheel wear progression

Distributed energy resources network connection considering reliability optimization using a NSGAII algorithm.

Trabalho apresentado conferência IEEE CPE-POWERENG, 4 a 6 de abril de 2017, Cádiz, EspanhaDistributed Energy Resources (DER) has been widely introduced in distribution networks in response to the increase of environmental awareness of the consumers. The benefits with the use of DER are increased with network reconfiguration, but in some countries exists the impossibility of island operation as well as the obligation to buy all the electricity generated. These limitations, in a network fault situation, causes a waste of resources, because of the unavailability of the DER. On other hand, the location of DER connection under the context of the improvement of the reliability indexes has not been studied. Thus, this paper will propose a multi objective optimization of the location of DER connection considering the switching devices placement to increase network reliability and availability of DER, minimizing at the same time the investment in equipment in a no island operation environment. For the resolution of the proposed formulation, it will be used the multi objective algorithm NSGA-II (Fast Non-dominated Sorting Genetic Algorithm). The formulation of the problem also considers a composite index made up of DER and interruption duration. This approach is applied to a real utility distribution network, with the results presented and discussed.N/

Contact detection approach between wheel and rail surfaces

This work presents a general formulation to identify the contact points for the interaction between wheels and rails in the context of railway dynamics simulations. This formulation treats the wheel and rail as parametric surfaces and searches the contact between each wheel strip and the rail independently to avoid the numerical difficulties due to the wheel concave zone. This methodology assumes the rail as locally straight and takes advantage that its potential contacting surface is always convex. For the evaluation of contact forces, two Hertzian-based models are employed for normal and creep forces. A trailer vehicle running on a curved track is used to demonstrate the effectiveness of this methodology.The first authorissupported by the Portuguese Foundation for Science and Technology (FCT) under grant PD/BD/114154/2016.This work is also supported by FCT with the reference project UIDB/04436/202