Search results for "Water"

Underwater Multirobot Cooperative Intervention MAC Protocol

2020

This work introduces a Medium Access Control (MAC) protocol designed to allow a group of underwater robots that share a wireless communication channel to effectively communicate with each other. The goal of the Underwater Multirobot Cooperative Intervention MAC (UMCI-MAC) protocol presented in this work is to minimize the end to end delay and the jitter. The access to the medium in UMCI-MAC follows a Time Division Multiple Access (TDMA) strategy which is arbitrated by a master, which also has the capability to prioritize the transmission of some nodes over the rest of the network. Two experiments have been carried out with a team of four Autonomous Underwater Vehicles (AUV) in order to comp…

Lemna minor L. jako biomonitor punktowych źródeł zanieczyszczenia metalami ciężkimi ekosystemów wodnych

2017

Regulation of motility of cells from marine sponges by calcium ions

1996

Sponges are known not to contain muscle and nerve cells. Since sponge cells are characterized by high motility we determined the effect of intracellular calcium ion concentration ([Ca2+]i) on their motility. Addition of the Ca2+ ionophore ionomycin to dissociated cells from the marine sponge Suberites domuncula caused in Ca(2+)-containing artificial seawater (ASW) an increase in motility from 0.2 micron/min (absence of the ionophore) to 3.7 microns/min (presence of ionomycin). When the experiments were performed in Ca(2+)-free medium, no effect of ionomycin could be observed. In parallel experiments the changes of [Ca2+]i using the dye Fura-2 were measured. The experiments revealed that ion…

Analysis of the Potential of an Increase in Yeast Output Resulting from the Application of Additional Process Wastewater in the Evaporator Station

2019

This paper reports the results of an analysis of process wastewater streams in the context of an increase in yeast production. This research is based on the analysis of data from the biggest yeast factory in Europe. The research presented in this paper involves the analysis of the influence of direction of additional wastewater into the evaporator station on yeast production. In the process wastewater, nitrogen is mainly present in organic forms. The analysis reported in this paper involves the concentration of total nitrogen in wastewater streams, as it is the main parameter applied to determine the amount of wastewater that can be applied in agricultural fields. Directing additional waste…

Zastosowanie badań biomonitoringowych do oceny zanieczyszczenia metalami ciężkimi wybranych ekosystemów

2016

Celem przeprowadzonych badań był biomonitoring zanieczyszczenia wybranymi metalami ciężkimi: Mn, Fe, Cu, Zn, Cd, Ni i Pb terenu w pobliżu zbiornika Janów (woj. świętokrzyskie) oraz wody w niecce zbiornika. Metale ciężkie w matrycach środowiskowych, takich jak glony Palmaria palmata, mchy Pleurozium schreberi i gleba, oznaczano metodą absorpcyjnej spektrometrii atomowej. Na podstawie przeprowadzonych badań i wyznaczonych współczynników akumulacji względnej (RAF) dla eksponowanych próbek glonów wykazano niejednorodne zanieczyszczenie wód zbiornika, szczególnie miedzią i kadmem. Wartości RAF dla tych metali wynosiły odpowiednio od 0,08 do 0,51 i od 0,17 do 0,91. W nielicznych miejscach pomiaro…

Analysis of Water Quality of the Stobrawa River at the Location of the Walce Small Retention Reservoir

2018

Małe zbiorniki wodne spełniają funkcje gospodarcze, energetyczne, przyrodnicze, rekreacyjne i poprawiają bilans wodny. Budując zbiornik wodny, oprócz zagadnień ilościowych wody, należy także wziąć pod uwagę jakość wody, która będzie retencjonowana w zbiorniku. Często wykorzystaniu zbiornika, jak i jego istnieniu, mogą zagrozić zanieczyszczenia dopływające do niego głównie z wodą i rumowiskiem. Ważne są badania monitoringowe w zlewniach rzek na których zamierza się budować małe zbiorniki wodne, ponieważ w tych zlewniach najczęściej nie prowadzi się badań jakości wody. Bardzo ważnym problemem jest więc zanieczyszczenie zbiorników planowanych. Celem pracy jest analiza jakości wód rzeki Stobraw…

Cadmium Metal–Organic Frameworks Based on Ditopic Triazamacrocyclic Linkers: Unusual Structural Features and Selective CO 2 Capture

2017

International audience; Two three-dimensional cadmium metal organic frameworks with general formula [Cd-2(L-1)(H2O)(3)](NO3)(0.7)(HCOO)(0.2)Br-0.1 (Cd2L1, L-1 = 1,4,7-tris(4-carboxybenzy1)-1,4,7-triazacyclononane) and Cd(HL2)(H2O)(2) (CdL2, L-2 = 1,4,7-tris(3-(4-benzoate)prop-2-yn-1-yl)-1,4,7-triazacydononane) based on 1,4,7-triazacyclononane N-functionalized by different arylcarboxylic acids were prepared under solvothermal conditions and characterized by single crystal X-ray analysis and porosity measurements. The crystal structure of Cd2L1 reveals a cationic net with a bcs topology,. and nodes are constituted by dinuclear cadmium complexes, in which each cadmium atom adopts a hexacoordin…

Terrestrial carbohydrates support freshwater zooplankton during phytoplankton deficiency

2016

Article

Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

2016

Abstract Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective p…

Inferring phytoplankton community composition with a fatty acid mixing model

2015

Abstract. The taxon specificity of fatty acid composition in algal classes suggests that fatty acids could be used as chemotaxonomic markers for phytoplankton composition. The applicability of phospholipid-derived fatty acids as chemotaxonomic markers for phytoplankton composition was evaluated by using a Bayesian fatty acid-based mixing model. Fatty acid profiles from monocultures of chlorophytes, cyanobacteria, diatoms, euglenoids, dinoflagellates, raphidophyte, cryptophytes and chrysophytes were used as a reference library to infer phytoplankton community composition in five moderately humic, large boreal lakes in three different seasons (spring, summer and fall). The phytoplankton commu…