Predators are traditionally classified as generalists and specialists based on the presence of adaptations that increase efficiency of prey capture and consumption and selection of particular prey types. Nevertheless, empirical evidence comparing foraging efficiency between generalist and specialist carnivores is scarce. We compared the prey-capture and feeding efficiency in a generalist and a specialist (araneophagous) spider predator. By using two related species, the generalist Harpactea rubicunda (Dysderidae) and the specialist Nops cf. variabilis (Caponiidae), we evaluated their fundamental trophic niche by studying the acceptance of different prey. Then, we compared their predatory behavior, efficiency in capturing prey of varying sizes, feeding efficiency, and nutrient extraction. Nops accepted only spiders as prey, while Harpactea accepted all offered prey, confirming that Nops is stenophagous, while Harpactea is euryphagous. Further, Nops displayed more specialized (stereotyped) capture behavior than Harpactea, suggesting that Nops is a specialist, while Harpactea is a generalist. The specialist immobilized prey faster, overcame much larger prey, and gained more mass (due to feeding on larger prey) than the generalist. Both the specialist and the generalist spider extracted more proteins than lipids, but the extraction of macronutrients in the specialist was achieved mainly by consuming the prosoma of the focal prey. We show that the specialist has more efficient foraging strategy than the generalist.

• MeSH
• druhová specificita MeSH
• fyziologická adaptace MeSH
• fyziologie výživy zvířat * MeSH
• pavouci fyziologie   MeSH
• predátorské chování * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Eutrophication of water by nutrient pollution remains an important environmental issue. The aim of this study was to evaluate the nutrient uptake capacity of an algal biofilm as a means to treat polluted water. In addition, the study investigated the nutrient removal process. The algal biofilm was able to remove 99% of phosphorus within 24 hours of P addition, with the PO4-P concentration in inflowing water ranging from 3 to 10 mg L-1. Different patterns of phosphorus and nitrogen removal were observed. Daily quantity of removed NO3-N ranged from 2 to 25% and was highly dependent on solar irradiance. Precipitation of phosphorus during the removal process was studied using X-ray diffraction analyses and was not confirmed in the biofilm. The biofilm system we constructed has a high efficiency for phosphorus removal and, therefore, has great potential for integration into wastewater treatment processes.

• MeSH
• biodegradace MeSH
• biofilmy * MeSH
• čištění vody * MeSH
• dusík * MeSH
• fosfor * MeSH
• odpad tekutý - odstraňování MeSH
• Publikační typ
• časopisecké články MeSH

This study summarizes the empirical literature on fat taxes and thin subsidies to assess their efficiency and efficacy as instruments of public policy to control obesity. Three specific types of taxes are studied in the literature: food group taxes; nutrient taxes; and nutrient index taxes. Anumber of studies use food expenditure data to assess the impact of various taxes on obesity and therefore only indirectly measure the impacts of taxes and subsidies on obesity. These studies generally conclude that food group taxes, nutrient taxes and nutrient index taxes have a small impact on the purchases of food and the nutrients purchased. Other studies use the body mass index as the explanatory variable and thus measure the impacts of taxes on body mass index directly. Nutrient taxes are found to be more effective than food group taxes, although even for nutrient taxes, the effects are small. In general, thin subsidies seem to offer more effective control of obesity than obesity taxes. However, due to the small effects of both fat taxes and thin subsidies, they are not recommended as instruments of food and nutrition policy.

• MeSH
• daně ekonomika   MeSH
• dietní sacharidy ekonomika   MeSH
• dietní tuky ekonomika   MeSH
• energetický příjem MeSH
• index tělesné hmotnosti MeSH
• lidé MeSH
• obchod ekonomika   MeSH
• obezita prevence a kontrola   MeSH
• potraviny ekonomika   MeSH
• socioekonomické faktory MeSH
• výživová politika * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The placenta plays a critical role in maternal-fetal nutrient transport and fetal protection against drugs. Creating physiological in vitro models to study these processes is crucial, but technically challenging. This study introduces an efficient cell model that mimics the human placental barrier using co-cultures of primary trophoblasts and primary human umbilical vein endothelial cells (HUVEC) on a Transwell®-based system. Monolayer formation was examined over 7 days by determining transepithelial electrical resistance (TEER), permeability of Lucifer yellow (LY) and inulin, localization of transport proteins at the trophoblast membrane (immunofluorescence), and syncytialization markers (RT-qPCR/ELISA). We analysed diffusion-based (caffeine/antipyrine) and transport-based (leucine/Rhodamine-123) processes to study the transfer of physiologically relevant compounds. The latter relies on the adequate localization and function of the amino-acid transporter LAT1 and the drug transporter P-glycoprotein (P-gp) which were studied by immunofluorescence microscopy and application of respective inhibitors (2-Amino-2-norbornanecarboxylic acid (BCH) for LAT1; cyclosporine-A for P-gp). The formation of functional monolayer(s) was confirmed by increasing TEER values, low LY transfer rates, minimal inulin leakage, and appropriate expression/release of syncytialization markers. These results were supported by microscopic monitoring of monolayer formation. LAT1 was identified on the apical and basal sides of the trophoblast monolayer, while P-gp was apically localized. Transport assays confirmed the inhibition of LAT1 by BCH, reducing both intracellular leucine levels and leucine transport to the basal compartment. Inhibiting P-gp with cyclosporine-A increased intracellular Rhodamine-123 concentrations. Our in vitro model mimics key aspects of the human placental barrier. It represents a powerful tool to study nutrient and drug transport mechanisms across the placenta, assisting in evaluating safer pregnancy therapies.

• MeSH
• biologické modely MeSH
• biologický transport MeSH
• endoteliální buňky pupečníkové žíly (lidské) * metabolismus   MeSH
• inulin metabolismus   MeSH
• isochinoliny MeSH
• kokultivační techniky MeSH
• leucin metabolismus   MeSH
• lidé MeSH
• maternofetální výměna látek * MeSH
• P-glykoprotein metabolismus   MeSH
• placenta * metabolismus   MeSH
• rhodamin 123 metabolismus   MeSH
• těhotenství MeSH
• trofoblasty * metabolismus   MeSH
• Check Tag
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Despite the importance of phosphorus as a nutrient for humans and its role in ecological sustainability, its high abundance, resulting in large part from human activities, causes eutrophication that negatively affects the environment and public health. Here, we present the use of ferrate(VI) as an alternative agent for removing phosphorus from aqueous media. We address the mechanism of phosphate removal as a function of the Fe/P mass ratio and the pH value of the solution. The isoelectric point of γ-Fe2O3 nanoparticles, formed as dominant Fe(VI) decomposition products, was identified to play a crucial role in predicting their efficiency in removing of phosphates. Importantly, it was found that the removal efficiency dramatically changes if Fe(VI) is added before (ex-situ conditions) or after (in-situ conditions) the introduction of phosphates into water. Removal under in-situ conditions showed remarkable sorption capacity of 143.4 mg P per gram of ferric precipitates due to better accessibility of active surface sites on in-situ formed ferric oxides/oxyhydroxides. At pH = 6.0-7.0, complete removal of phosphates was observed at a relatively low Fe/P mass ratio (5:1). The results show that phosphates are removed from water solely by sorption on the surface of γ-Fe2O3/γ-FeOOH core/shell nanoparticles. The advantages of Fe(VI) utilization include its environmentally friendly nature, the possibility of easy separation of the final product from water by a magnetic field or by natural settling, and the capacity for successful phosphate elimination at pH values near the neutral range and at low Fe/P mass ratios.

• MeSH
• chemické látky znečišťující vodu chemie   MeSH
• čištění vody MeSH
• fosfáty MeSH
• nanočástice MeSH
• železité sloučeniny chemie   MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH

We studied cell properties including carbon allocation dynamics in the globally abundant and important cyanobacterium Prochlorococcus marinus strain PCC 9511 grown at three different growth rates in nitrogen-limited continuous cultures. With increasing nitrogen limitation, cellular divinyl chlorophyll a and the functional absorption cross section of Photosystem II decreased, although maximal photosynthetic efficiency of PSII remained unaltered across all N-limited growth rates. Chl-specific gross and net carbon primary production were also invariant with nutrient-limited growth rate, but only 20% of Chl-specific gross carbon primary production was retained in the biomass across all growth rates. In nitrogen-replete cells, 60% of the assimilated carbon was incorporated into the protein pool while only 30% was incorporated into carbohydrates. As N limitation increased, new carbon became evenly distributed between these two pools. While many of these physiological traits are similar to those measured in other algae, there are also distinct differences, particularly the lower overall efficiency of carbon utilization. The latter provides new information needed for understanding and estimating primary production, particularly in the nutrient-limited tropical oceans where P. marinus dominates phytoplankton community composition.

• MeSH
• dusík metabolismus   MeSH
• Prochlorococcus metabolismus   MeSH
• sinice metabolismus   MeSH
• uhlík metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

The establishment of phytoextraction crops on highly contaminated soils can be limited by metal toxicity. A recent proposal has suggested establishing support crops during the critical initial phase by metal immobilization through soil amendments followed by subsequent mobilization using elemental sulphur to enhance phytoextraction efficiency. This 'combined phytoremediation' approach is tested for the first time in a pot experiment with a highly contaminated soil. During a 14-week period, relatively metal-tolerant maize was grown in a greenhouse under immobilization (before sulphur (S) application) and mobilization (after S application) conditions with soil containing Cd, Pb and Zn contaminants. Apart from the control (C) sample, the soil was amended with activated carbon (AC), lignite (Lig) or vermicompost (VC) all in two different doses (dose 1~45 g additive kg-1 soil and dose 2~90 g additive kg-1 soil). Elemental S was added as a mobilization agent in these samples after 9 weeks. Biomass production, nutrient and metal bioavailability in the soil were determined, along with their uptake by plants and the resulting remediation factors. Before S application, Cd and Zn mobility was reduced in all the AC, Lig and VC treatments, while Pb mobility was increased only in the Lig1 and VC1 treatments. Upon sulphur application, Fe, Mn, Cd, Pb and Zn mobility was not significantly affected in the C, AC and VC treatments, nor total Cd, Pb and Zn contents in maize shoots. Increased sulphate, Mn, Cd, Pb and Zn mobilities in soil together with related higher total S, Mn, Pb and Zn contents in shoots were observed in investigated treatments in the last sampling period. The highest biomass production and the lowest metal toxicity were seen in the VC treatments. These results were associated with effective metal immobilization and showed the trend of steady release of some nutrients. The highest remediation factors and total elemental content in maize shoots were recorded in the VC treatments. This increased phytoremediation efficiency by 400% for Cd and by 100% for Zn compared to the control. Considering the extreme metal load of the soil, it might be interesting to use highly metal-tolerant plants in future research. Future investigations could also explore the effect of carbonaceous additives on S oxidation, focusing on the specific microorganisms and redox reactions in the soil. In addition, the homogeneous distribution of the S rate in the soil should be considered, as well as longer observation times.

• MeSH
• biodegradace MeSH
• biologická dostupnost MeSH
• biomasa MeSH
• dřevěné a živočišné uhlí chemie   MeSH
• fosfor farmakokinetika   MeSH
• kompostování MeSH
• kukuřice setá účinky léků   růst a vývoj   metabolismus   MeSH
• látky znečišťující půdu analýza   farmakokinetika   MeSH
• půda chemie   MeSH
• regenerace a remediace životního prostředí metody   MeSH
• síra * farmakokinetika   MeSH
• těžké kovy analýza   farmakokinetika   MeSH
• výhonky rostlin účinky léků   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

Mineral nutrition of crop plants is one of the major challenges faced by modern agriculture, particularly in arid and semi-arid regions. In alkaline calcareous soils, the availability of phosphorus and zinc is critically less due to their fixation and precipitation as complexes. Farmers use fertilizers to fulfill crop requirements, but their efficacy is less, which increases production costs. Plant growth-promoting rhizobacteria (PGPR) can improve the availability of crop nutrients through solubilizing the insoluble compounds of phosphorus and zinc in soil. In the present study, a total of 40 rhizobacterial isolates were isolated from cotton rhizosphere and screened for improving cotton growth through the solubilization of phosphorus and zinc. Out of these 40 isolates, seven isolates (IA2, IA3, IA6, IA7, IA8, IA13, and IA14) efficiently solubilized insoluble rock phosphate while seven isolates (IA10, IA16, IA20, IA23, IA24, IA28, and IA30) were more efficient in solubilizing insoluble zinc oxide. In liquid media, strain IA7 (2.75 μg/mL) solubilized the highest amount of phosphate while the highest concentration of soluble zinc was observed in the broth inoculated with strain IA20 (3.94 μg/mL). Seven phosphate-solubilizing and seven zinc-solubilizing strains were evaluated using jar trial to improve the growth of cotton seedlings, and the results were quite promising. All the inoculated treatments showed improvement in growth parameters in comparison with control. Best results were shown by the combined application of IA6 and IA16, followed by the combination of strains IA7 and IA20. Based on the jar trial, the selected isolates were further characterized by plant growth-promoting characters such as siderophores production, HCN production, ammonia production, and exopolysaccharides production. These strains were identified through 16S rRNA sequencing as Bacillus subtilis IA6 (accession # MN005922), Paenibacillus polymyxa IA7 (accession # MN005923), Bacillus sp. IA16 (accession # MN005924), and Bacillus aryabhattai IA20 (accession # MN005925). It is hence concluded that the integrated use of phosphate-solubilizing and zinc-solubilizing strains as potential inoculants can be a promising approach for improving cotton growth under semi-arid conditions.

• MeSH
• Bacillus klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• fosfáty metabolismus   MeSH
• fosfor metabolismus   MeSH
• fylogeneze MeSH
• Gossypium růst a vývoj   mikrobiologie   MeSH
• očkovadla agrotechnická klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• Paenibacillus polymyxa klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• půda chemie   MeSH
• půdní mikrobiologie MeSH
• rhizosféra MeSH
• RNA ribozomální 16S genetika   MeSH
• zinek metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

Úprava konzistence tekutin a stravy je terapeutickou možností při dysfagii. Pro jednotlivé úpravy viskozity tekutiny a modifikace pevné stravy existuje množství označení, které jsou terminologicky nejednoznačné, vágní, např. „konzistence medu“ nebo „měkká strava“. Nejednoznačnost terminologie ovlivňuje efektivitu a bezpečnost aplikace této terapeutické metody, kdy výsledná konzistence tekutiny či potravy může být pro odlišné chápání vágního termínu reologicky odlišná od konzistence, která byla zjištěna jako bezpečná během objektivního vyšetření polykání. IDDSI (International Dysphagia Diet Standardization Initiative) je iniciativa usilující o aplikaci mezinárodní standardizované terminologie potravin a tekutin s upravenou texturou pro využití u osob s dysfagií všech věkových kategorií, v různých typech zdravotnických i sociálních zařízeních a v různých kulturních prostředích. Cílem IDDSI je zlepšit bezpečnost orálního příjmu u pacientů s dysfagií a zároveň zlepšit podmínky pro výzkum v oblasti dysfagie.

Texture-modified diet and thickening liquids are a therapeutic option for dysphagia. Many of the terms referring to liquid viscosity modifications and solid diet modifications are terminologically ambiguous and vague, e. g. “honey consistency liquid” or “soft-textured diet.” The inconsistent terminology adversely affects patient safety and the efficiency of the application of this therapeutic method. Possible misunderstanding of the vague terms between staff members can result in using a different consistency of the fluid or food from the consistency that was found to be safe during the objective swallowing examination. The International Dysphagia Diet Standardization Initiative (IDDSI) is seeking application of international standardized terminology for texture-modified foods and liquids for use in people with dysphagia of all ages, in all care settings, and in different cultural settings. The goal of IDDSI is to improve patient safety of oral intake and evolve the field of dysphagia research.

• MeSH
• lidé MeSH
• pití MeSH
• poruchy polykání * diagnóza   klasifikace   ošetřování   MeSH
• přijímání potravy * MeSH
• strava, jídlo, výživa MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

The alga Parachlorella kessleri, strain CCALA 255, grown under optimal conditions, is characterized by storage of energy in the form of starch rather than lipids. If grown in the complete medium, the cultures grew rapidly, producing large amounts of biomass in a relatively short time. The cells, however, contained negligible lipid reserves (1-10% of DW). Treatments inducing hyperproduction of storage lipids in P. kessleri biomass were described. The cultures were grown in the absence or fivefold decreased concentration of either nitrogen or phosphorus or sulfur. Limitation by all elements using fivefold or 10-fold diluted mineral medium was also tested. Limitation with any macroelement (nitrogen, sulfur, or phosphorus) led to an increase in the amount of lipids; nitrogen limitation was the most effective. Diluted nutrient media (5- or 10-fold) were identified as the best method to stimulate lipid overproduction (60% of DW). The strategy for lipid overproduction consists of the fast growth of P. kessleri culture grown in the complete medium to produce sufficient biomass (DW more than 10 g/L) followed by the dilution of nutrient medium to stop growth and cell division by limitation of all elements, leading to induction of lipid production and accumulation up to 60% DW. Cultivation conditions necessary for maximizing lipid content in P. kessleri biomass generated in a scale-up solar open thin-layer photobioreactor were described.

• MeSH
• biomasa MeSH
• biotechnologie MeSH
• chlorofyl analýza   metabolismus   MeSH
• Chlorophyta metabolismus   MeSH
• fotobioreaktory MeSH
• kultivační média MeSH
• lipidy biosyntéza   MeSH
• mastné kyseliny analýza   metabolismus   MeSH
• metabolismus lipidů MeSH
• mikrořasy metabolismus   MeSH
• oxid uhličitý metabolismus   MeSH
• škrob analýza   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH