The influence of selenium and deiodinases blockers on juvenile rats body weight

In this work there was investigated the influence of selenium and deodinases blockers on juvenile rats body weight during three months. The experiment was carried out on 64 rats divided into eight groups with eight individual animals per group. Following groups were formed: 1. Se+PTU-IA- (control group), 2. Se+PTU+IA+, 3. Se+PTU+IA-, 4. Se+PTU- IA+, 5. Se-PTU-IA-, 6. Se-PTU+IA+, 7. Se-PTU+IA- and 8. Se-PTU-IA+. The groups labeled (Se+) were selenium adequate and they were fed with food that contained 0.334 mg Se/kg. The groups labeled (Se-) were selenium deficient and obtained food with 0.031 mg Se/kg. As deiodinases blockers there were used propylthiouracil (PTU+) in a dose of 150 mg/L of drinking water and iopanoic acid (IA+) in a dose of 6 mg/100 g TM intraperitoneally. Body weight of experimental rats was measured every seven days. After three weeks of treatment there were taken blood samples of animals from all experimental groups and following parameters were determined: selenium concentration in blood, thyroxine (T4), triiodothyronine (T3) and thyroidstimulating hormone (TSH) in blood plasma. Analysis of the samples showed that the animals from the groups treated with PTU had lower body weight in regard to the control group, as well as lower concentration of T3 and T4 in plasma. Selenium deficient rats had lower average body weight compared to the selenium adequate ones after three weeks, but there were no differences in thyroid hormones concentration. The lowest average body weight was noticed in selenium deficient rats groups treated with PTU. [Projekat Ministartsva nauke Republike Srbije, br. TR31050 i br. TR31003

Power generation using parallel connected microbial fuel cells systems

The use of microbial fuel cells (MFCs) for the purpose of obtaining energy from nature has grown in the second decade of the 21st century. Due to the lack of fossil fuels and less and less available renewable energy sources, MFCs have great potential for obtaining small amounts of electricity. Increasing attention is focused on the use of such types of energy. The aim of this paper is to analyse the current generation of two parallel-connected MFC cells and the power generation obtained in this way

Respiration of microorganisms in the MFC system during the generation of energy from river sediment

Aktivnost mikroorganizama je direktno povezana sa njihovim disanjem. U prisustvu velikih količina biodostupne organske supstance, brzina disanja mikroorganizama je veća. Praćenje disanja je postalo bitan parametar u raznim procesima biodegradacije otpadne supstance. Stoga, cilj ovog rada obuhvata praćenje ćelijskog disanja pomoću Micro-Oxymax respirometra, kako bi se dobio bolji uvid u prisustvo dostupne organske supstance u upotrebljenom rečnom sedimentu za generisanje električne energije pomoću MF

Evaluation of Physiological State of Pen Shell Pinna nobilis (Linnaeus, 1758) by a Non-Invasive Heart Rate Recording under Short-Term Hyposalinity Test

A non-invasive laser fiber-optic method based on infrared sensors for heart rate (Hr) recording was applied to assess the physiological condition of Pinna nobilis. During 2017, the specimens of P. nobilis were sampled at three sites within the Boka Kotorska Bay, Montenegro and used for ex situ experiments with short-term reduction/restoration of ambient salinity to evaluate their physiological adaptive capacity based on heart rate recovery time (Trec). Mean Trec for specimens from Sv. Nedjelja (reference site), Dobrota and Sv. Stasije were 72 ± 3, 91 ± 7 and 117 ± 15 min, while the coefficients of variation (CV) were 0.12, 0.13 and 0.17, respectively. Resting heart rate (Hrrest) and Trec showed statistically significant differences between the groups of mussels from Dobrota and Sv. Stasije in comparison to the reference site. Statistically significant correlations were observed between Trec and shell length/width, which was not the case in comparison between Hrrest and shell length/width. The lower adaptive capacity within the P. nobilis specimens from Dobrota and Sv. Stasije in comparison to the reference site could occur due to stress induced by deterioration of environmental conditions, which could have led to impairment of the physiological state of the mussels evaluated by Hr. All the specimens of P. nobilis survived the experimental treatments; afterwards, they were successfully transplanted at the Dobrota site. The experimental unit with sensor technology applied in this study can provide Hr recording in real time and could have an application in monitoring the physiological/health state of P. nobilis individuals maintained in aquaria

Utilization of carbon fiber in the context of microbial fuel cell systems

The paramount challenge of the 21st century lies in the profound energy demands imposed by contemporary society. The utilization of energy derived from non-renewable sources, notably coal, oil, and their byproducts, is intrinsically associated with grave environmental repercussions, primarily manifested in the form of pollution. The notion of fuel cells stands as a prospective resolution to this problem, offering a sustainable avenue for energy production devoid of environmentally adverse emissions. The aim of this research was to explore the potential of carbon cloth electrodes in the Microbial Fuel Cell (MFC) system

Influence of Microbial Community on Power generation Using MFC System

Global worldwide population and urbanization in general have created an increasing need for new energy sources. These sources need to be renewable, but it is also very important to respect the principles of environmental protection. Microbial fuel cells (MFC) are a green technology that has been attracting more and more attention in the last decade. MFC presents a system that produces electrical current through metabolic processes of microorganisms, such as the decomposition of organic matter. In this process, chemical energy is directly converted into electrical energy

Analytical aspects of a single-chamber system of microbial fuel cells (MFC)

Description of a single chamber microbial fuel cells (MFC), its construction and operation, processing and analysis of experimental measurements in laboratory conditions is give

Influence of Microbial Community on Power Generation Using MFC System

Introduction: Global worldwide population and urbanization in general have created an increasing need for new energy sources. These sources need to be renewable, but it is also very important to respect the principles of environmental protection. Microbial fuel cells (MFC) are a green technology that is attracting more and more attention in the last decade. MFC presents a system which produces electrical current through metabolic processes of microorganisms such is the decomposition of organic matter. In this process chemical energy is directly converted into electrical energy [1-3]. The performance of MFC depends on several factors: temperature, the composition of the sediment, the material from which the electrodes are made, but certainly, one of the prominent factors is the activity of a microbial community. In this paper, efficiency of two MFC systems will be compared to obtain the highest current and power generation. One of them contains only river sediment as a source of microorganisms, while the other was biostimulated by microorganisms isolated from the same river sediment [2-3]. Methods: The river sediment was placed between a set of inox electrodes in a plastic container, with a total volume of 201 cm3 (MFC I). The second MFC (MFC II) was made in the same way, but a consortium of microorganisms, Clostridium sp., Bacillus sp. and Tepidibacter sp. isolated from the river sediment was added to the sediment. The set of resistors already established in our previous studies were used for the measurement of the amount of voltage, which was then used to obtained the values of current and power [4]. Results: After five days of measuring the generated voltage via MFC I and II, the results for current and power density were obtained. In MFC I, the highest current density was recorded on the fifth day and was 76 mA/ m3 while the power was 1.5 mW/m3 . With MFC II, the results were visibly higher, where the current was increased three times (up to 210 mA/m3 ), and the power by as much as 4 times higher compared to the results of MFC I (6 mW/m3 ). Conclusion: Results show that MFC I has lower values than the sediment stimulated by a consortium of microorganisms in the MFC II. The community of microorganisms greatly contributes to improving the performance of the sediment itself, by generating more power density

Analytical aspects of a single-chamber system of microbial fuel cells (MFC)

Description of a single chamber microbial fuel cells (MFC), its construction and operation, processing and analysis of experimental measurements in laboratory conditions is give

Mikrobna gorivna ćelija – hemijska i mikrobiološka karakterizacija sedimenta

Microbial fuel cells (MFCs) represent new potential energy sources through which electricity is generated, and among numerous advantages is that the emission of harmful gases is missing. MFC is a type of biological fuel cell, a system that converts chemical energy into electrical power by microorganisms. These systems can be constructed in many ways so that there are one-chamber, two-chamber and complex MFCs. MFCs are good alternative sources of energy offering possibility of application that can be found in the biosensor industry, hydrogen or electricity production systems and wastewater treatment plants. In this paper, characterization of the sediment used in a single chamber MFC is presented. The sediment used to form the microbial fuel cell is characterized by microbiological, chemical and analytical parameters.Mikrobne gorivne ćelije (Microbial fuel cell-MFC) predstavljaju nove potencijalne izvore energije, preko kojih se generiše električna energija, a među brojnim prednostima je i ta što izostaje emisija štetnih gasova. MFC su vrsta bioloških gorivnih ćelija, sistema koji konvertuju hemijsku energiju u električnu pomoću mikroorganizama. Postoji više načina konstrukcije i među njima se nalaze jednokomorne, dvokomorne i složene MFC. Takođe, mikroorganizmi i supstrati koji se koriste u MFC, koje ti mikroorganizmi obrađuju u hemijskim procesima, mogu da budu različitog porekla i da imaju različite karakteristike. MFC su dobri alternativni izvori energije koji svoju potencijalnu primenu nalaze u industriji biosenzora, sistemima za proizvodnju vodonika ili električne energije i postrojenjima za prečišćavanje otpadnih voda. U ovom radu dat je opis sedimenta korišćenog u sistemu jednokomorne MFC, okarakterisan pomoću mikrobioloških, hemijskih i analitičkih parametara.Related to: [http://cer.ihtm.bg.ac.rs/handle/123456789/3307