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Psittacidae is one of the most endangered families of birds in the world. Knowledge of their nutrition is important for understanding their survival and productivity in the wild, as well as for their adequate husbandry under human care. Hand‐rearing is a common practice for psittacines, however research on their nutrition is limited. We analysed the predicted metabolisable energy, crude protein, crude fat, minerals and the essential amino acid profiles of the crop contents from free‐living nestlings of scarlet macaws (Ara macao) and red‐and‐green macaws (Ara chloropterus) from southeastern Peru, Cuban Amazons (Amazona leucocephala bahamensis) from the Bahamas, lilac‐crowned Amazons (Amazona finschi) from northwestern Mexico and thick‐billed parrots (Rhynchopsitta pachyrhyncha) from northern Mexico. The crop content of the different parrot species displayed remarkably similar nutritional profiles, considering their diversity in habitats, geographic ranges and food sources. The crude protein and crude fat concentrations in crop samples were particularly similar for the Ara and Amazona species, while the thick‐billed parrot stood out for its higher crude fat and lower crude protein content. Wider variations were found among the concentrations of sodium (Na) and iron (Fe), proline and tryptophan. Compared with the requirements of 6−12 weeks leghorn chickens, all free‐ranging parrot diets contained lower crude protein, calcium (Ca), potassium (P) and Na concentrations. The hand‐feeding formulas contained lower crude fat, magnesium (Mg), arginine, valine and phenylalanine concentrations, as well as much higher levels of Ca and zinc (Zn), in comparison with parrot crop samples. Our data suggest that a single formulation could be used to hand‐rear Ara and Amazona sp. of 3 weeks of age and older, while a different formulation would likely be more appropriated for Rhynchopsitta sp. Experimental studies should evaluate if increasing the concentration of crude fat, Mg, arginine, valine and phenylalanine enhances psittacine chick growth and health. [ABSTRACT FROM AUTHOR]

Research on psittacine nutrition is limited, and nestling requirements are poorly understood. This study analysed fatty acid (FA) profiles of crop contents of free‐living scarlet macaws (Ara macao, n = 18), red‐and‐green macaws (Ara chloropterus, n = 5), Cuban parrots (Amazona leucocephala bahamensis, n = 27), lilac‐crowned Amazons (Amazona finschi, n = 33) and thick‐billed parrots (Rhynchopsitta pachyrhyncha, n = 32). The same analysis was carried out on 15 commercial parrot hand‐feeding formulas. The mean FA concentration of the crop samples of each species ranged from 15% to 53% DM for crop samples and ranged from 6% to 22% for hand‐feeding formulas. Long‐chain FA represented over 92% of all FA in the crop samples and over 81% of all FA in the commercial formulas. Parrot species shared similarities in saturation profiles of crop samples, ranging between 13%–29% saturated fatty acids (SFA), 12%–40% monounsaturated fatty acids (MUFA) and 39%–58% polyunsaturated fatty acids (PUFA). All studied psittacines, except for the red‐and‐green macaw, were within the range of values for hand‐rearing formulas. Palmitic acid was the most common SFA in scarlet macaws, red‐and‐green macaws, Cuban parrot, thick‐billed parrot and in all but one commercial formula. Palmitic and stearic acids dominated the SFA in the samples of the Lilac‐crowned Amazon. Oleic acid was the most common MUFA in all hand‐feeding formulas as well as in the crop samples, except for the lilac‐crowned amazon and the thick‐billed parrot where vaccenic acid dominated. Linoleic acid was by far the most common PUFA found in the crop samples as well as in the hand‐feeding formulas. PUFA were largely dominated by the n6 family, both in the crop samples and the formulas. The data presented on nestling diets of free‐living parrot species provide a foundation for future researchers to test whether increasing FA concentration in hand‐feeding formulas improves nestling development or if species‐specific formulas will be advantageous. [ABSTRACT FROM AUTHOR]

We determine the number of non‐isomorphic semi‐Heyting algebras on an n‐element chain, where n is a positive integer, using a recursive method. We then prove that the numbers obtained agree with those determined in [1]. We apply the formula to calculate the number of non‐isomorphic semi‐Heyting chains of a given size in some important subvarieties of the variety of semi‐Heyting algebras that were introduced in [5]. We further exploit this recursive method to calculate the numbers A(n,m) of non‐isomorphic semi‐Heyting chains with n elements such that removing the mth element (1

Static magnetic field gradients superimposed on the electromagnetic trapping potential of a Penning trap can be used to implement laser‐less spin–motion couplings that allow the realization of elementary quantum logic operations in the radio‐frequency regime. An important scenario of practical interest is the application to g‐factor measurements with single (anti‐)protons to test the fundamental charge, parity, time reversal (CPT) invariance as pursued in the Baryon Antibaryon Symmetry Experiment (BASE) collaboration. The classical and quantum behavior of a charged particle in a Penning trap with a superimposed magnetic field gradient is discussed. Using analytic and numerical calculations, it is found that it is possible to carry out a SWAP gate between the spin and the motional qubit of a single (anti‐)proton with high fidelity, provided the particle has been initialized in the motional ground state. The implications of the findings for the realization of quantum logic spectroscopy in this system are discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND Imazaquin is a chiral herbicide which displays high mobility in soils. Like other imidazolinones, imazaquin is available for use only as racemic mixture of its enantiomers. In this work, several clay materials were assayed as adsorbents of imazaquin, and then the most suitable material was selected to prepare a clay‐based slow release imazaquin nanoformulation containing exclusively the biologically active R‐enantiomer. Next, laboratory experiments were conducted to illustrate the benefits of using the clay‐based R‐imazaquin formulation over the free (non‐supported) racemic herbicide or the free pure R‐imazaquin enantiomer regarding its leaching behavior and bioefficacy. RESULTS: The clay material selected as a carrier for R‐imazaquin, hexadecyltrimethylammonium‐saturated montmorillonite (SA‐HDTMA), combined a high affinity for the herbicide and a high stability of the clay‐herbicide adsorption complex. In a simulated scenario of high water input shortly after herbicide application, the clay‐based R‐imazaquin formulation displayed reduced leaching and increased bioefficacy compared to free racemic imazaquin and free R‐imazaquin. CONCLUSION: The new clay‐R‐imazaquin formulation prepared, besides avoiding the environmental impact caused by the application of the less active S‐enantiomer, reduced the herbicide leaching losses and prolonged the herbicidal activity, by increasing the residence time of the herbicide in the topsoil. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Soil incubation and column leaching experiments were conducted to address the question of whether the type of formulation (unsupported versus clay supported) and repeated applications of the chiral fungicide ( RS)-metalaxyl affected the enantioselectivity of its dissipation and leaching in a slightly alkaline, loamy sand agricultural soil. RESULTS Regardless of the type of formulation and the number of fungicide applications, the R-enantiomer of metalaxyl was degraded faster than the S-enantiomer, but the individual degradation rates of R- and S-metalaxyl were highly affected by the different application regimes assayed ( t 1/ 2 = 2-104 days). Repeated applications accelerated the degradation of the biologically active R-metalaxyl enantiomer, whereas they led to slower degradation of the non-active S-metalaxyl enantiomer. The type of formulation had less influence on the dissipation rates of the enantiomers. For all formulations tested, soil column leachates became increasingly enriched in S-enantiomer as the number of fungicide applications was increased, and application of metalaxyl to soil columns as clay-based formulations reduced the leaching of both enantiomers. CONCLUSION Pesticide application conditions can greatly influence the enantioselective dissipation of chiral pesticides in soil, and hence are expected to exert a great impact on both the biological efficacy and the environmental chiral signatures of pesticides applied as mixtures of enantiomers or racemates to agricultural soils. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Oxyfluorfen herbicide residues have been previously reported in surface and ground water in the Guadalquivir river basin in Spain. Soil factors and processes (sorption, dissipation, and leaching) influencing the potential offsite transport of oxyfluorfen to surface and ground water were characterized in laboratory experiments for two soils from Southern Spain. The influence of olive-oil mill waste amendment on the soil processes was also determined. Oxyfluorfen sorption in unamended soils was not significantly affected by soil active components (organic matter and clay fraction). However, a significant increase in soil sorption of the herbicide was observed upon amendment. Laboratory half-life values for oxyfluorfen in unamended sandy clay loam and silty clay soils at 40% moisture content and 25°C were 29 and 19 days, respectively, and it increased by a factor of four upon amendment. Oxyfluorfen's mobility along soil profile increased with the amendment in leaching studies at 25°C, suggesting that dissolved organic matter of amendment can play an important role enhancing soil vertical movement of the pesticide. The increase in soil adsorption and persistence observed with olive-oil mill waste amendment can promote its losses by runoff following winter application, whereas vertical movement of oxyfluorfen can be enhanced following spring application when olive-oil mill waste amendment is also applied. [ABSTRACT FROM AUTHOR]

Bentazone and S-metolachlor are herbicides widely used for the control of broad leaf weeds in crops such as corn and soybean. The effect of the addition to soils with different texture and organic matter content of an organic waste (OW) from oil olive production (alperujo) on different processes affecting behaviour of both herbicides was evaluated. Sorption of S-metolachlor increased upon amendment. A six-fold increase could be observed for Kd values on the sandy soil amended at 10% rate and a five-fold increase on the soil with higher content on clay (48%) and same rate of OW (10%). The results revealed that although an increase in soil total pore volume was found upon amendment (from 210 to 266 mm3 g−1 in sandy (S) soil, from 215 to 251 in clayey (19% silt) (T) soil, and from 240 to 289 in clayey (50% silt) (E) soil), leaching of the herbicide S-metolachlor was greatly reduced (from 61 to 3.5% in the S-soil and from 37 to <1% in the clayey T-soil) since its behaviour in soils is strongly affected by sorption processes. Bentazone leaching was only slightly delayed upon amendment. Half-life of both herbicides also increased upon amendment. The greatest increase was observed with the higher rate of OW (10%) in the soils with higher content of clay (48% in T-soil and 31% in E-soil). A 17-fold increase was observed for S-metolachlor half-life in T-soil and a four-fold increase for bentazone in E-soil. Thus, the use of the by-product from olive oil extraction can be a good strategy to reduce the off-site movement of S-metolachlor by increasing its soil sorption, and therefore the risk of water pollution can be diminished. However, the higher persistence of both herbicides in organic amended soils should be taken into account. [ABSTRACT FROM AUTHOR]

In this paper we prove that the free algebras in a subvariety \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal V$\end{document} of the variety \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {SH}$\end{document} of semi-Heyting algebras are directly decomposable if and only if \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal V$\end{document} satisfies the Stone identity. [ABSTRACT FROM AUTHOR]

There are few experiments aiming at determining directly the mass of the electron antineutrino with a sensitivity of 0.2 eV by analyzing the end of the β-decay spectrum of specific nuclei. This sensitivity can be only reached if the uncertainties arising from systematic effects are very small and very well determined. The same holds for experiments aiming at improving the sensitivity in the determination of the mass of the electron neutrino using electron-capture (ϵ)-decaying nuclei. One important input in these cases is an accurate Q-value of the decay which can be unambiguously determined from the difference of the mass of the mother and the daughter nuclei by means of Penning traps. In order to reach the required sensitivity, a novel device called Quantum Sensor is under construction at the University of Granada (Spain). The device will allow measuring atomic masses, and therefore Q-values from decays with unprecedented accuracy and sensitivity, using fluorescence photons from a laser-cooled ion instead of electronic detection. This paper will give an overview on Q-value measurements performed with Penning traps, relevant for neutrino mass spectrometry, describing the Quantum Sensor and the facility under construction. It will end by presenting the status of the project. [ABSTRACT FROM AUTHOR]

We conducted nutritional analyses of diets offered to and ingested by seven pairs of horned guans ( Oreophasis derbianus) in three zoos. Digestibility was calculated with individually housed birds ( n=1 at each zoo). Diets offered varied widely among institutions, both in ingredients fed as well as in nutrient composition. Feeding selectivity was evident through differences in composition of diets offered vs. consumed, with fruit (bananas, grape, and/or plantain) and avocado (when offered) highly preferred; green leaves, poultry pellets, and other vegetables comprised lesser proportions of the diet. All facilities fed 2-3X more food than consumed, allowing a great degree of choice of preferred items and potentially consumption of nutritionally imbalanced diets-in particular, mineral constituents. Diets were highly digestible; dry matter (DM) digestion coefficients ranged from 70 to ∼90%; protein digestibility varied from 30 to 80%; fat was >90% digestible. Diet composition was compared with known nutritional requirements of domestic avian species, and feeding recommendations discussed. Despite the wide variability in nutrient composition of diets eaten (i.e. protein 6-10% of DM; fat 2-17% of DM), no overt health problems were noted and all pairs had successfully reproduced on these diets. It is suggested that horned guans may have nutrient requirements more similar to those suggested for other frugivorous birds than values determined for poultry as the physiologic model. Comparisons with native food items, as well as more detailed nutrient balance studies, may provide even better guidelines for captive management of this highly endangered species. Zoo Biol 28:319-330, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The article reports on a study of the effects of organoclay-based formulations of 4-chloro-2-methylphenoxyacetic acid (MCPA) and olive oil waste amendment in decreasing MCPA leaching in a sandy loam soil. It made batch adsorption and column leaching studies for its analysis. It used an organic residue which was a solid waste from olive oil production. Its results found out that organoclay-based formulations of MCPA lessen the release rate and the leaching of the herbicide as compared to conventional formulation. It also showed that greater adsorption and reduced leaching of MCPA in the soil has resulted from increase of soil organic matter upon MCPA amendment.

Metalaxyl and tricyclazole are two fungicides widely used in Spain in vineyard and rice crops respectively. In this study an investigation has been made of the effect of three organic amendments [two commercial amendments, solid fertiormont (SF) and liquid fertiormont (LF), and a residue from the olive oil production industry, alperujo (OW)] on fungicide fate in soils. Changes in soil porosity on amendment were studied by mercury intrusion porosimetry, sorption-desorption studies were performed by the batch equilibration method, dissipation of metalaxyl and tricyclazole in the soil was studied at -33 kPa moisture content and 20 °C and leaching was studied in hand-packed soil columns. Amendments with SF and LF reduced soil porosity, while OW increased porosity through an increase in pore volume in the highest range studied. Tricyclazole sorbed to soils to a much higher extent than metalaxyl. With some exceptions, sorption of both fungicides increased on amendment, especially in the case of SF-amended soils, which rendered the highest Koc values. In soils amended with the liquid amendment LF, sorption either remained unaffected or decreased, and this decrease was much higher in the case of metalaxyl and a soil with 70% clay. In this clay soil, amendment with OW, of very high soluble organic matter content, also decreased metalaxyl sorption. Tricyclazole is more persistent in soil than metalaxyl, and both fungicides were found to be more persistent in amended soils than in unamended soils. Leaching of metalaxyl and tricyclazole in soil columns was inversely related to sorption capacity. The low recoveries of tricyclazole in leachates and in soil columns when compared with metalaxyl, a less persistent fungicide, were attributed to diffusion into micropores and to increase in sorption with residence time in the soil, both processes favoured by the low mobility of tricyclazole. [ABSTRACT FROM AUTHOR]

Sorption-desorption interactions of pesticides with soil determine the availability of pesticides in soil for transport, plant uptake and microbial degradation. These interactions are affected by the physical and chemical properties of the pesticide and soil and, for some pesticides, their residence time in the soil. While sorption-desorption of many herbicides has been characterised, very little work in this area has been done on herbicide metabolites. The objective of this study was to characterise sorption-desorption of two sulfonylaminocarbonyltriazolinone herbicides, flucarbazone and propoxycarbazone, and their benzenesulfonamide and triazolinone metabolites in two soils with different physical and chemical properties. Kf values for all four chemicals were greater in clay loam soil, which had higher organic carbon and clay contents than loamy sand. Kf-oc ranged from 29 to 119 for the herbicides and from 42 to 84 for the metabolites. Desorption was hysteretic in every case. Lower desorption in the more sorptive system might indicate that hysteresis can be attributed to irreversible binding of the molecules to soil surfaces. These data show the importance of characterisation of both sorption and desorption of herbicide residues in soil, particularly in the case of prediction of herbicide residue transport. In this case, potential transport of sulfonylaminocarbonyltriazolinone herbicide metabolites would be overpredicted if parent chemical soil sorption values were used to predict transport. [ABSTRACT FROM AUTHOR]

Presents information on adsorption-desorption studies of metalaxyl in fifteen agricultural soil samples from Southern Portugal and Spain following a batch equillibrium method. Experimental methods; Results and discussion on the study; Conclusions.

Organoclays were assayed as matrices in which to associate herbicides, with the aim of decreasing product losses that could give rise to water contamination from agricultural activities. Fenuron was selected as model of a very mobile and highly water-soluble herbicide. Two different organoclays of high (A-HDT) and low (H-C18) reversible fenuron sorption were selected. Herbicide-organoclay complexes were prepared from the two organoclays and with two different fenuron contents (20 and 40g AIkg -1) and two different mixing times, so as to form a series of weak and strong complexes. The release of fenuron from those complexes into water and water/soil suspensions gave values of T50 (time to release 50% of the fenuron content) ranging from 0.3 mill to 2400 h. The total fenuron released in these closed systems ranged from 48 to 80% of the fenuron in the complex. The organoclay type (high or low sorptivity) had the greatest influence on fenuron release, followed by the strong or weak complex, suggesting that herbicide-organoclay interactions are the main factors controlling release. Soil column leaching experiments showed fenuron-organoclay complexes to be effective in reducing the peak herbicide concentration in the leachate to a half (6 μm) or a quarter (3 (μm) of that obtained from the free technical compound (12(μm). Herbicide lost through leaching was reduced from 78% for the free technical fenuron to 50-30%, depending on the organoclay used as carrier and the strength of the complex. Bioassay with ryegrass showed that the weak fenuron/H-C18 complex (40g AIkg -1) gave the same herbicidal activity as technical fenuron. The potential suitability of low-sorptive organoclays for conferring slow-release properties on the fenuron complex has been demonstrated. [ABSTRACT FROM AUTHOR]

SummaryThe phytobilin chromophores of phycobiliproteins and phytochromes are biosynthesized from heme in a pathway that begins with the opening of the tetrapyrrole macrocycle of protoheme to form biliverdin IXα, in a reaction catalyzed by heme oxygenase. A gene containing an open reading frame with a predicted polypeptide that has a sequence similar to that of a conserved region of animal microsomal heme oxygenases was identified in the published genomic sequence of Synechocystis sp. PCC 6803. This gene, named ho1, was cloned and expressed in Escherichia coli under the control of the lacZ promoter. Cells expressing the gene became green colored due to the accumulation of biliverdin IXα. The size of the expressed protein was equal to the predicted size of the Synechocystis gene product, named HO1. Heme oxygenase activity was assayed in incubations containing extract of transformed E. coli cells. Incubations containing extract of induced cells, but not those containing extract of uninduced cells, had ferredoxin‐dependent heme oxygenase activity. With mesoheme as the substrate, the reaction product was identified as mesobiliverdin IXα by spectrophotometry and reverse‐phase HPLC. Heme oxygenase activity was not sedimented by centrifugation at 100 000 g. Expression of HO1 increased several‐fold during incubation of the cells for 72 h in iron‐deficient medium. [ABSTRACT FROM AUTHOR]