Use Of Complex Mixtures Research Articles

Nitrogen, potassium and sulphur availability from residue-based fertilisers produced in Denmark applied singly or combined

In organic farming systems, nutrients taken up by crops should be replenished by the recycling of agricultural and urban organic waste to close nutrient cycles. However, the availability of organic wastes permitted for application in organic farming is limited, and organic farmers usually have to apply manure from conventional farms, which is considered to be contentious. Alternative nutrient sources acceptable for application in organic farming are therefore needed to supply available nutrients to maintain or increase organic food production. In this study, we investigated the ability of manure, digested manure, manure co-digested with the organic fraction of municipal solid waste, Fertigro® (a by-product from heparin production), and ash from straw to supply N, K and S to ryegrass grown in pots. We sought to establish whether the use of complex mixtures to obtain more suitable nutrient ratios can benefit plant growth. Digested manure and manure co-digested with the organic fraction of municipal solid waste gave on average 50% greater plant growth and 63% higher N recovery than manure, while no significant differences were observed in terms of K recovery. Fertigro® showed similar plant growth and nutrient uptake to the mineral S and N positive controls, while the addition of straw ash demonstrated similar K recovery as that observed for the mineral K positive control. The mixture of Fertigro® with manure co-digested with the organic fraction of municipal solid waste and ash was outstanding among the waste-based fertilisers in terms of amount of N, K and S supplied for plant uptake. However, further efforts are needed to confirm these benefits under field conditions.

Interactions between Medical Plant-Derived Bioactive Compounds: Focus on Antimicrobial Combination Effects.

It is accepted that the medicinal use of complex mixtures of plant-derived bioactive compounds is more effective than purified bioactive compounds due to beneficial combination interactions. However, synergy and antagonism are very difficult to study in a meticulous fashion since most established methods were designed to reduce the complexity of mixtures and identify single bioactive compounds. This study represents a critical review of the current scientific literature on the combined effects of plant-derived extracts/bioactive compounds. A particular emphasis is provided on the identification of antimicrobial synergistic or antagonistic combinations using recent metabolomics methods and elucidation of approaches identifying potential mechanisms that underlie their interactions. Proven examples of synergistic/antagonistic antimicrobial activity of bioactive compounds are also discussed. The focus is also put on the current challenges, difficulties, and problems that need to be overcome and future perspectives surrounding combination effects. The utilization of bioactive compounds from medicinal plant extracts as appropriate antimicrobials is important and needs to be facilitated by means of new metabolomics technologies to discover the most effective combinations among them. Understanding the nature of the interactions between medicinal plant-derived bioactive compounds will result in the development of new combination antimicrobial therapies.

Compound mixtures based on hydrolyzed Polyacrylonitrilereducing soil electrical resisctivity

THE PURPOSE. The purpose of the article is to define the reasons to improve the system of grounding devices design. Author studies technical decisions that reduce grounding resistance values. Results are given researches how a mineral conductive mixture, that normalizes grounding, influences a seasonal coefficient. Analysed the results of the experimental surveys. Аlso evaluates a test grounding devise’s resistance decrease compared to the resistance decrease of a control grounding device. METHODS. While solving the above problem, a number of field experiments were carried out to measure the resistance values of experimental circuit grounding devices after their near-electrode soil space had been treated with the mixture that improves the resistance of a grounding wire. RESULTS. The composition of the mixture that normalizes (reduces) soil electrical resistivity has been developed, it has contained hydro-stabilizing and lowdispersed conducting additives. There has been proposed the analytical expressions to evaluate equivalent soil electrical resistivity values after aporton of soil had been submitted by the mineral conducting mixture. CONCLUSION. The use of the mixtures based on hydrolyzed polyacrylonitrile is most effective together with the grounding wires buried in soil no deeper than the soil freezing depth that is located in the soil layers with maximum seasonal fluctuations, and will increase with the increase of the contact area of such grounding wires with the soil treated with hydrolyzed polyacrylonitrile. Additional decrease of a seasonal coefficient for the vertical compound grounding wires apparently is due to the mixture influencing their parts mounded near the ground surface. The use of complex mixtures containing both hydro-stabilizing additives and low-dispersed conducting substances allows up to three times decrease of the resistance values of a grounding device compared to a control grounding device, it allows to even seasonal fluctuation of resistance of a grounding device, and to decrease mounting capital investment for a grounding device by means of the decrease of the number of the electrodes and the territory on which they are located.

<i>In sit</i> assessment of genotoxicity in tadpoles (Amphibia: Anura) in impacted and protected areas of Chapada Diamantina, Brazil

We evaluated the genotoxic potential of surface water bodies in an area impacted by agrochemicals, in the Ibicoara-Mucugê agropole, Bahia and those within protected areas in Chapada Diamantina, Bahia, Brazil, using the micronucleus test as a biomarker in tadpole species native neotropicals. Our hypothesis is that the closer to agricultural farms, the more affected by mutagenic and genotoxic substances will be the environment and resident organisms. The micronucleus frequencies were determined in tadpoles of 11 species collected in 11 surface water bodies in coffee, corn, vegetable, and pumpkin plantations, as well as in adjacent sites within a protection area. Tadpoles of seven species found in agricultural sites exhibited higher frequencies of micronuclei compared to the six species from the protected locations. The species Bokermannohyla oxente and Leptodactylus latrans collected in agricultural areas exhibited the highest frequencies of micronucleated erythrocytes compared to the populations from the protected areas (p <0.05). Our results indicate that compounds present in surface water bodies in agricultural areas of the Ibicoara-Mucugê farm have genotoxic effects on anurans, showing the stress responses caused by agricultural activities associated with the use of complex mixtures of pesticides. Thus, anurans are excellent sentinel species in environmental monitoring, previously indicating the effect of xenobiotics on the environment.

Ancient restorations at Hierapolis of Phrygia (Denizli, Turkey): Interdisciplinary research on materials and technologies

The restoration of architectural monuments constituted a common practice in the ancient Mediterranean world and the use of artificial binders in repairing blocks is attested both by literary sources and archaeological evidence. However, the knowledge on the use of these ancient binders and their components is limited, due to the shortness and indefiniteness of the ancient recipes and the difficulty of obtaining and analyzing samples from blocks that have remained exposed to atmospheric agents and have undergone degradation.The paper focuses on the exceptional context of Hierapolis of Phrygia (Denizli, Turkey), where many ancient binders used in the restoration of Roman Imperial-era buildings (Sanctuary of Apollo, Theatre, North Agora and Ploutonion) have been identified. Thanks to the good state of conservation of these materials, the paper offers the unique opportunity for studying the role of organic additives used in the ancient bonding mortars and understanding the technologies adopted in the architectural restoration. Several analytical methodologies (Pyrolosis and Gas chromatography coupled with Mass Spectroscopy; X-ray diffractometry and Optical Microscopy) were applied to identify the organic and inorganic components.The mortars sampled in Hierapolis showed the presence of casein, animal glue, beeswax and Pinaceae resin, in agreement with the survived ancient recipes on bonding mortars. However, the archaeometric data revealed the use of complex mixtures, which are also attested by the literary sources. In particular, the use of calcite together with various organic additives appeared to be a common practice. Criteria of selection and use of the different mixtures have been discussed.

Improved Canine and Human Visceral Leishmaniasis Immunodiagnosis Using Combinations of Synthetic Peptides in Enzyme-Linked Immunosorbent Assay

BackgroundZoonotic visceral leishmaniasis (VL) is a severe infectious disease caused by protozoan parasites of the genus Leishmania and the domestic dogs are the main urban parasite reservoir hosts. In Brazil, indirect fluorescence antibody tests (IFAT) and indirect enzyme linked immunosorbent assay (ELISA) using promastigote extracts are widely used in epidemiological surveys. However, their sensitivity and specificity have often been compromised by the use of complex mixtures of antigens, which reduces their accuracy allowing the maintenance of infected animals that favors transmission to humans. In this context, the use of combinations of defined peptides appears favorable. Therefore, they were tested by combinations of five peptides derived from the previously described Leishmania diagnostic antigens A2, NH, LACK and K39.Methodology/Principal FindingsCombinations of peptides derived A2, NH, LACK and K39 antigens were used in ELISA with sera from 44 human patients and 106 dogs. Improved sensitivities and specificities, close to 100%, were obtained for both sera of patients and dogs. Moreover, high sensitivity and specificity were observed even for canine sera presenting low IFAT anti-Leishmania antibody titers or from asymptomatic animals.Conclusions/SignificanceThe use of combinations of B cell predicted synthetic peptides derived from antigens A2, NH, LACK and K39 may provide an alternative for improved sensitivities and specificities for immunodiagnostic assays of VL.

Integration of biological monitoring, environmental monitoring and computational modelling into the interpretation of pesticide exposure data: Introduction to a proposed approach

Open field, variability of climatic and working conditions, and the use of complex mixtures of pesticides makes biological and environmental monitoring in agriculture, and therefore risk assessment and management, very complicated. A need of pointing out alternative risk assessment approaches, not necessarily based on measures, but simple, user-friendly and reliable, feasible also in the less advanced situations and in particular in small size enterprises, arises. This aim can be reached through a combination of environmental monitoring, biological monitoring and computational modelling. We have used this combination of methods for the creation of “exposure and risk profiles” to be applied in specific exposure scenarios, and we have tested this approach on a sample of Italian rice and maize herbicide applicators. We have given specific “toxicity scores” to the different products used and we have identified, for each of the major working phases, that is mixing and loading, spraying, maintenance and cleaning of equipment, the main variables affecting exposure and inserted them into a simple algorithm, able to produce “exposure indices”. Based on the combination of toxicity indices and exposure indices it is possible to obtain semiquantitative estimates of the risk levels experienced by the workers in the exposure scenarios considered. Results of operator exposure data collected under real-life conditions can be used to validate and refine the algorithms; moreover, the AOEL derived from pre-marketing studies can be combined to estimate tentative biological exposure limits for pesticides, useful to perform individual risk assessment based on technical surveys and on simple biological monitoring. A proof of principle example of this approach is the subject of this article.

Combined use of Paracoccidioides brasiliensis recombinant rPb27 and rPb40 antigens in an enzyme-linked immunosorbent assay for immunodiagnosis of paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is one of the most important endemic mycoses in Latin America; it's usually diagnosed by observation and/or isolation of the etiologic agent, Paracoccidioides brasiliensis, as well as by a variety of immunological methods, such as complement fixation and immunodiffusion. Although these approaches are useful, historically their sensitivity and specificity have often been compromised by the use of complex mixtures of undefined antigens. The use of combinations of purified, well-characterized antigens appears preferable and may yield good results. In the present study combinations of the previously described 27-kDa recombinant antigen (rPb27) and a recombinant 40-kDa-molecular-mass antigen (rPb40) from this fungus, that was identified by Goes et al. (2005) through the AST strategy as a homolog of Neurospora crassa calcineurin B, were used in an indirect enzyme linked immunosorbent assay (ELISA) for diagnosis and follow-up of patients with PCM. The complete coding cDNA of rPb40 and rPb27 were cloned into a pET-21a and a pET-DEST 42 plasmid, respectively, expressed in E. coli with a his-tag and purified by affinity chromatography. Among 109 PCM serum samples analyzed, a homogeneous IgG response to these proteins was observed. 62 serum samples from patients with other diseases, 18 from patients with other mycosis and 23 from healthy individuals were also studied. Detection of anti-rPb27 and anti-rPb40 antibodies in sera of patients with PCM by ELISA using a combination of the two purified proteins showed a sensitivity of 96% with a specificity of 100% in relation to control normal human sera and to sera from patients with other systemic mycosis and 93.5% to sera from patients with diverse infections. The use of this two proteins combination provided an excellent immunodiagnosis assay with great values of sensitivity and specificity, even in relation to sera from patients with other mycosis, making possible the standadization of a new methodology to diagnose this important mycosis, with a good confiability and reprodutibility.

Grazing Schedule Effect on Forage Production and Nutritive Value of Diverse Forage Mixtures

The use of complex mixtures (mixtures of more than three species) may increase yield of pastures; however, we know little about how grazing management affects the productivity of mixtures. A grazing experiment was performed during 2005 and 2006 near State College, PA, to compare mixtures of grasses, legumes, and chicory (Cichorium intybus L.) for their botanical composition, nutritive value, and forage production under two grazing schedules: when the sward reached 25 cm in height (sward height schedule, SH) or when alfalfa (Medicago sativa L.) reached the bud stage (morphology or MP schedule). The SH schedule produced 30% more dry matter (DM) than the MP schedule averaged for 2 yr. Forage yield of the five‐species (6427 kg ha−1 in 2005 and 6624 kg ha−1 in 2006) and seven‐species (6816 kg ha−1 in 2005 and 6772 kg ha−1 in 2006) mixtures was stable during the contrasting weather of 2005 and 2006. Grass monoculture with N and simple mixtures (two species, grass–legume) produced 989 kg ha−1 more DM than the complex mixtures in 2006 when weather conditions were favorable. The SH schedule produced forage of better nutritive value compared with the MP schedule at first harvest in both years [20 g kg−1 less acid detergent fiber (ADF) in 2006; 25 g kg−1 in 2005, 53 g kg−1 in 2006 more neutral detergent fiber (NDF); 21 g kg−1 in 2005, 30 g kg−1 in 2006 more crude protein (CP); and 33 g kg−1 in 2006, 53 g kg−1 more in vitro true dry matter digestibility (IVTDMD)]. Complex mixtures of forage species provide more consistent yields of DM than binary grass–legume mixtures or grass monocultures in variable environments.

Intake and Performance of Lactating Cows Grazing Diverse Forage Mixtures

Twenty multiparous Holstein cows in midlactation grazed pastures of 4 forage mixtures in a 12-wk study repeated during 2 grazing seasons to determine if forage mixture complexity affected intake and productivity of lactating dairy cows. The forage mixtures were 1) orchardgrass plus white clover [2 species (SP)]; 2) orchardgrass, white clover, and chicory (3SP); 3) orchardgrass, tall fescue, perennial ryegrass, red clover, birdsfoot trefoil, and chicory (6SP); and 4) 6SP mixture plus white clover, alfalfa, and Kentucky bluegrass (9SP). Total herbage intake was similar among forage mixtures, averaging 12.0kg/d across all forage mixtures and years. Milk production and composition were not affected by forage mixture or year, and averaged 34.6kg/d, 3.4%, and 2.8% for milk production, milk fat percentage, and milk protein percentage, respectively. The conjugated linoleic acid content of milk fat was higher for cows that grazed the 3SP, 6SP, and 9SP mixtures than from cows that grazed the 2SP mixture (1.02 vs. 0.87g of conjugated linoleic acid/100g of fatty acids, respectively). Blood glucose, blood urea nitrogen, and nonesterified fatty acids were not affected by forage mixture and averaged 69.2mg/dL, 13.4mg/dL, and 277.5μEq/L, respectively. The results of this study indicate that altering the forage mixture in pastures did not affect dry matter intake, milk production, or blood metabolite profiles of lactating cows. The use of complex mixtures of forages in grazing systems should not affect dairy cow performance.

Gradient elution reversed-phase chromatographic isolation of individual glycerophospholipid molecular species

We describe a gradient elution reversed-phase high-performance liquid chromatographic approach for isolation of individual glycerophospholipid molecular species which greatly improves resolution and reduces run time compared to isocratic techniques. Separations were optimized and elution order and retention time data established by synthesizing 37 different homogeneous phospholipids comprising the major alkylacyl, diacyl and plasmalogen molecular species in samples derived from mammalian sources. Empirical equations which predict the elution order of individual species were derived. The method was validated with the use of complex mixtures of choline and ethanolamine glycerophospholipid species from isolated rabbit cardiomyocytes and porcine endothelial cells.

NADH:ubiquinone oxidoreductase from bovine heart mitochondria. cDNA sequences of the import precursors of the nuclear-encoded 39 kDa and 42 kDa subunits

The 39 kDa and 42 kDa subunits of NADH:ubiquinone oxidoreductase from bovine heart mitochondria are nuclear-coded components of the hydrophobic protein fraction of the enzyme. Their amino acid sequences have been deduced from the sequences of overlapping cDNA clones. These clones were amplified from total bovine heart cDNA by means of the polymerase chain reaction, with the use of complex mixtures of oligonucleotide primers based upon fragments of protein sequence determined at the N-terminals of the proteins and at internal sites. The protein sequences of the 39 kDa and 42 kDa subunits are 345 and 320 amino acid residues long respectively, and their calculated molecular masses are 39,115 Da and 36,693 Da. Both proteins are predominantly hydrophilic, but each contains one or two hydrophobic segments that could possibly be folded into transmembrane alpha-helices. The bovine 39 kDa protein sequence is related to that of a 40 kDa subunit from complex I from Neurospora crassa mitochondria; otherwise, it is not related significantly to any known sequence, including redox proteins and two polypeptides involved in import of proteins into mitochondria, known as the mitochondrial processing peptidase and the processing-enhancing protein. Therefore the functions of the 39 kDa and 42 kDa subunits of complex I are unknown. The mitochondrial gene product, ND4, a hydrophobic component of complex I with an apparent molecular mass of about 39 kDa, has been identified in preparations of the enzyme. This subunit stains faintly with Coomassie Blue dye, and in many gel systems it is not resolved from the nuclearcoded 36 kDa subunit.