Phytoplankton evolution during the creation of a biofloc system for shrimp culture

[EN] Microalgae play a key role in the dynamics of biofloc technology aquaculture systems. Some phytoplankton groups, such as diatoms, are desired for their high nutritional value and contribution to water quality. Other groups, such as cyanobacteria, are undesired because of their low nutritional value and capacity of producing toxins. So, monitoring the phytoplankton community structure and succession is key for managing biofloc systems. However, research on phytoplankton in these systems is scarce and mostly done by microscopy. The primary objective of this research was to estimate phytoplankton community structure in shrimp biofloc system water samples, using high-performance liquid chromatography methods and CHEMTAX software. The major groups present in our system were diatoms, euglenophytes, cyanobacteria and chlorophytes, while dinoflagellates were only remarkable at the initial period. We observed a clear dominance of diatoms all along the 5 months that comprised a complete biofloc system culture. The characteristic succession of autotrophic processes by heterotrophs of the biofloc systems, was observed by the reduction of net primary production. Light intensity played a key role in determining the phytoplankton composition and abundance. Algal pigment analyses using high-performance liquid chromatography and subsequent CHEMTAX analysis in water samples was useful for estimating the phytoplankton community structure in the biofloc systems. However, we found some limitations when the biofloc system was in heterotrophic mode. Under these conditions, some dinoflagellates and cyanobacteria behaved as heterotrophs and lost or decreased their biomarkers pigments. So, further research is needed to increase knowledge on the accuracy of high-performance liquid chromatography /CHEMTAX under these conditions.Financial support for this research was provided by Conselleria d’Educació, Investigació, Cultura i Esport of the Generalitat Valenciana, through the program VALi+D, fle number ACIF/2014/244. We would like to express our deepest thanks to Professor Luis Henrique da Silva Poersch of FURG (Universidade Federal do Rio Grande) and Ivan Vidal (Langostinos el Real) for his support. Finally, the authors wish to thank Le Gouessant and Michaël Metz for providing the commercial feed.Llario-Sempere, F.; Rodilla, M.; Escrivá-Perales, J.; Falco, S.; Sebastiá-Frasquet, M. (2018). Phytoplankton evolution during the creation of a biofloc system for shrimp culture. 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Type of day forecasting

In recent years the dynamic of the telecommunications industry has changed significantly. This industry becomes deregulated and more competitive in many countries, such as France, United States, United Kingdom, and Australia. In Australia, there are currently more than 10 active mobile phone providers. As a result, consumers are changing their patterns of behaviour. They move in and out of different segments of the market, and from arrangements with one provider to another, with prices becoming highly competitive. At the same time, the change in technology is producing an explosion of new products, increasing the difficulty of forecasting. The deregulation and increased competition in the telecommunications industry has increased the pressure for forecasters to understand the new market and to be able to incorporate and respond quickly to new changes. One of the challenges is to accurately forecast the monthly revenue of mobile usage - the topic of this research. In comparison with other deregulated industries such as for energy, the forecasting literature in telecommunications is very poor. An extensive search with different web engines, such as Econlit, Web of Science, and Google, did not show any work in forecasting the monthly revenue of mobile usage. The purpose of this paper is to develop a model in order to forecast, with high accuracy, the monthly revenue of mobile usage in a deregulated market. Usually, the monthly revenue of mobiles usage is forecast by the direct calculation of usage and forecast yield and contains high errors as a consequence of bundles, discounts and reward options. For any operator, a wrong prediction of the monthly revenue of mobile usage provides misleading results and negatively influences the planning process. The forecasting model presented in this paper is developed using the indexes obtained from the number of each day type in the month, the weekly call profile and underlying patterns. Minutes of use (MOU) and monthly revenue figures for the period January 2004 to February 2005 were used. The minutes represent the total time spent on the mobile-to-mobile calls. The historical data includes the monthly revenue ($ millions) and the daily profile for the minutes (millions) (Figure 1). (Graph Presented) The methodology presented in this paper forecasts the mobile revenue with very high accuracy, with errors less than 1%. The software used for the modelling was Minitab and Excel, with macros developed in Visual Basic for Applications. Due to the confidentiality and price sensitivity of data, a direct comparison between these two methodologies cannot be provided. The next phase of the research is to forecast the monthly revenue of mobile usage using larger data and to include a direct comparison of the results provided by the old and new methodology

Implantation intraluminaler Stents zur Behandlung des Trachealkollaps beim Hund

Tracheal collapse is a progressive disease particularly of small breed dogs. In the terminal stage, when dyspnea becomes the dominating sign and is no longer manageable with medical treatment, a surgical procedure is necessary. With increasing frequency intraluminal tracheal stents are implanted minimal-invasively. In individual animals this is a lifesaving procedure, leading to immediate elimination of dyspnea. In most dogs cough for some time has to be anticipated as the stent acts as a foreign body, but severe complications like excessive formation of granulation tissue, stent migration or stent fracture are rare. Stents represent an attractive treatment modality for tracheal collapse in dogs with dyspnea

Ten Years Of Sustainable Construction Aspects From A North And A South Perspective – A Review From Sustainable Building Conferences 1998-2007.

This paper is about, from a North and South different perspective, how the international focus of sustainable construction issues has changed over the past ten years. It is a review from four different international and regional sustainable building conferences between 1998 and 2007. The paper is mostly based of the first author's notes from the conferences, especially from the plenary sessions and discussions, but some contributions are also considered and selected from breakout sessions and from the proceedings. The reviewed conferences are GBC98 in Vancouver, Canada 1998, SB02 in Oslo, Norway 2002, SB05 in Tokyo, Japan 2005 and the regional conference SB07 in Malmö, Sweden 2007. The perspectives presented in the paper are those of construction project and environmental manager from northern Europe and from architects in southern Africa with an interest in sustainable construction. The findings of the paper shows that focus of sustainable construction matters has changed from almost solely environmental aspects to a more broad and transparent complexity of sustainability, including ecological-, economic- social- esthetical- and cultural aspects. It also reflects regional and national differences and some shifting views of focus about sustainability in the construction sector during the past ten years

Endoscopic ultrasonographic evaluation of the esophagus in healthy dogs

Objective-To characterize the ultrasonographic appearance of the canine esophagus. Animals-14 healthy Beagles. Procedures-Endoscopic ultrasonography (EUS) examinations were performed with a radial ultrasonographic gastrovideoscope in anesthetized dogs. Images were obtained at 3-cm intervals along the esophageal length to allow evaluation of the esophageal wall. Images were obtained with the probe in direct contact with the esophageal wall and with a water-filled balloon as a standoff. Results-Images were obtained with (12 dogs) and without (10) the water-filled balloon. Median thickness of the esophageal wall was 2.19 mm (range, 1.03 to 5.62 mm) in the proximal third of the esophagus, 2.15 mm (range, 1.10 to 4.45 mm) in the middle third, and 2.84 mm (range, 1.35 to 5.92 mm) in the distal third. Wall thickness differed significantly between proximal and distal thirds. Results were similar when the water-filled balloon was used. Esophageal wall layers appeared as 5 alternating hyperechoic and hypoechoic bands that could not be consistently identified in all dogs. All layers could be identified in 26 of 198 (13%) images, 3 layers could be identified in 67 of 198 (34%) images, and 105 of 198 (53%) images had no layers. Visual identification of layers in images obtained with and without the balloon did not differ significantly. Conclusions and Clinical Relevance-EUS appeared to be a useful technique for assessing esophageal wall integrity in dogs; however, complete evaluation of all layers could not be accomplished in all instances. Further studies with this technique in dogs are needed