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Of fundamental importance for the functioning of a community is the flow of energy and elements through its components. However, the question of how (if at all) the edge effect of habitats can drive elemental traits of organisms has hitherto been largely neglected issue in ecosystem ecology at the community level. We quantified the abundance of invertebrates and measured the elemental composition (K, Na, Ca, Mg, Cu, Zn, Fe, Mn, As, Cd, Co and Pb) of 15 different organisms within the plant-invertebrate food web (plant – oilseed rape pests/herbivores – pollinators = wild bees – saprovores – predators – parasitoids) sampled in 34 fields of a key bioenergy crop that is an exceptionally strong biodiversity driver, the oilseed rape. Then these were related to the individual field edge habitat features (including typically anthropogenic ones like dirt and tarred roads) measured within a 100 m radius around the invertebrate sampling sites. Our study showed that elemental traits of the plant-invertebrate food web components in oilseed rape crops varied owing to the habitat specificity determined at the relatively small spatial scale of an individual field, and that the elemental traits of these organisms differed from both an inter- and an intra-guild perspective. The major mechanistic explanation for most of these relationships seems to derive from the secondary gut content effect. Determining one single state for the homeostatic/stoichiometric regulation of chemical elements in invertebrates based on the application of whole-body metal concentrations is in principle impossible, because of the unknown noise caused by the inclusion of extracellular portions of metals in the analysis. It is thus imperative to develop consistent principles for assessing elemental traits of organisms that are based on highly sensitive and high-throughput analytical methods for the ionomic profiling of microsamples at the organ, tissue, cellular or even sub-cellular levels.

Objective The purpose of this study was to examine the relationship between dynapenia and metabolic risk factors in obese and nonobese older adults. Methods A total of 1453 men and women (age ≥70 years) from the Lifestyle Interventions and Independence for Elders (LIFE) Study were categorized as (1) nondynapenic/nonobese (NDYN-NO), (2) dynapenic/nonobese (DYN-NO), (3) nondynapenic/obese (NDYN-O), or (4) dynapenic/obese (DYN-O), based on muscle strength (Foundation for the National Institute of Health criteria) and body mass index. Dependent variables were blood lipids, fasting glucose, blood pressure, presence of at least 3 metabolic syndrome (MetS) criteria, and other chronic conditions. Results A significantly higher likelihood of having abdominal obesity criteria in NDYN-NO compared with DYN-NO groups (55.6 vs 45.1%, P ≤ .01) was observed. Waist circumference also was significantly higher in obese groups (DYN-O = 114.0 ± 12.9 and NDYN-O = 111.2 ± 13.1) than in nonobese (NDYN-NO = 93.1 ± 10.7 and DYN-NO = 92.2 ± 11.2, P ≤ .01); and higher in NDYN-O compared with DYN-O ( P = .008). Additionally, NDYN-O demonstrated higher diastolic blood pressure compared with DYN-O (70.9 ± 10.1 vs 67.7 ± 9.7, P ≤ .001). No significant differences were found across dynapenia and obesity status for all other metabolic components ( P > .05). The odds of having MetS or its individual components were similar in obese and nonobese, combined or not with dynapenia (nonsignificant odds ratio [95% confidence interval]). Conclusion Nonobese dynapenic older adults had fewer metabolic disease risk factors than nonobese and nondynapenic older adults. Moreover, among obese older adults, dynapenia was associated with lower risk of meeting MetS criteria for waist circumference and diastolic blood pressure. Additionally, the presence of dynapenia did not increase cardiometabolic disease risk in either obese or nonobese older adults.

Amino acid ionic liquids and amino acid ionic liquid-supported Schiff bases, derivatives of salicylaldehyde or benzaldehyde and various amino acids ( l -valine, l -leucine, L-isoleucine, l -threonine, l -histidine, l -methionine and l -tryptophan) have been investigated by means of various spectroscopic techniques (NMR, UV–Vis, IR). Their physico-chemical properties (glass transition temperature (T g ), decomposition temperatures at 5% (T d 5% ) and 50% (T d 50% ) weight loss, specific rotation [α], miscibility) have been also determined and compared. The influence of the Schiff base formation and presence of the intramolecular hydrogen bond on spectral parameters, thermal stability, glass transition temperature of tetrabutylammonium salts of amino acids have been shown.

Aerial insectivores through their insect diet can contribute to biotransfer of elements across habitats. We investigate the relationship between dietary composition as expressed by the contributions of six functional invertebrate prey groups (primarily of agriculturally subsidised invertebrates characteristic of agricultural areas in temperate regions of Europe) and concentrations of essential (Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Co) and non-essential (As, Cd, Pb) elements of environmental concern in the faeces of nestlings of three species of avian aerial insectivores – Common Swift Apus apus , Barn Swallow Hirundo rustica and House Martin Delichon urbicum – which breed sympatrically and use apparently similar resources of flying insect prey. There were significant differences between the species for 7 of the 12 elements (Ca, Zn, Cu, Co, As, Pb, Cd); these differences were attributable to the variable dietary composition, even though the concentrations of the elements varied enormously between the faecal samples from the individual species. Partial correlation analysis between the biomass (expressed in mg dry weight) of the six functional prey groups and faecal concentrations of elements showed the highest number of significant relationships for toxic metals (As, Pb and Cd). The results of the General Regression Model explaining faecal element concentrations revealed the different explanatory power of the effects of PCA (of six functional prey groups) dietary scores. A significant fit of GRM was obtained for 7 elements (Na, Mg, Fe, Mn, As, Pb, Cd) for Barn Swallows, 2 elements (Cu, As) for House Martins and 1 element (Mn) for Common Swifts. Overall, the results confirmed our predictions that the biomass of consumed coprophilous taxa and insects from crop habitats was positively correlated with the faecal concentrations of toxic elements. Unexpectedly, however, the faecal samples (primarily those of Common Swifts) that contained many oil-seed rape insect pests had lower Ca, Pb and Cd levels and a higher As level. Our study implies that the cross-boundary transfer of contaminants, primarily non-essential elements, by aerially foraging birds through the considerable accumulation of their faeces has potential consequences for the local biogeochemical cycle and environmental quality.

Three model metal complexes: Ni(NCS)L, Zn2(NCS)2L2 and Cd2(NCS)2L2, consisting of the SCN− anion(s) and L = 2-[(2-dimethylaminoethylimino)-methyl]-phenolate, have been studied by X-ray diffraction and solid state NMR spectroscopy. The metal cations in these complexes have different coordination modes: Ni2+ is almost square-planar, the Zn2+ cation in Zn2(NCS)2L2 is pentacoordinated, whereas Cd2+ is penta- and hexacoordinated in [Cd2(NCS)2L2]. The different coordination of the metal cations influences the chemical shifts of the metal cations and also the nitrogen atoms. These chemical shifts can be correlated with the M–N and M–O bond lengths (M = Ni2+, Zn2+, Cd2+).

The structures of the main tautomers of the Schiff base of salicylaldehyde with ethylamine and its protonated species have been studied by ESI MS, FT-IR as well as 1H, 13C and 15N NMR methods. The spectroscopic methods have provided clear evidence that the Schiff base exists in acetonitrile solution in a low barrier O⋯H⋯N imine–oxo tautomeric form. This form is also energetically favourable as indicated by PM5 calculations. This untypical Schiff base form is stabilized by a resonance effect with the nitro group and the interaction of the intramolecular hydrogen-bonded proton with acetonitrile via a intermolecular hydrogen bond. The protonated Schiff base exists in solution as imine–hydroxy form stabilized by intermolecular hydrogen bonds with nitro groups and solvent molecules.

Three Schiff bases obtained from substituted salicylaldehydes and 2-hydroxy-1-naphthaldehyde and aliphatic amines were investigated in terms of possible withdrawal of tautomeric proton from intramolecular hydrogen bridge. Three strong nitrogen bases: 1,8-bis(dimethylamino)naphtalene (DMAN), 1,1,3,3-tetramethylguanidine (TMG) and 1,8-bis(tetramethylguanidino)naphthalene (TMGN) were used as deprotonating agents in acetonitrile solution at room temperature. In the specified conditions it was found that only in the case of 5-nitrosalicylaldehyde and isopropyl amine derivative this process could be performed using TMG and TMGN as a base. The other derivatives, where bridged proton is shifted to oxygen or nitrogen atom, do not undergo such reaction. The deprotonation process was monitored by nitrogen and proton NMR measurements.

The aim of this study was to investigate the activity of antioxidant enzymes in the blood of White Stork Ciconia ciconia chicks (aged 19-54 days) in Poland in 2006. We took under consideration superoxide dismutase (SOD), catalase (CAT), ceruloplasmine (CP), glutathione peroxidase (GPx), glutathione reductase (GR) and the content of thiobarbituric acid-reactive substances (malondialdehyde) in polluted (copper manufacture), suburban areas, at the Odra meadows, and at swamps near Baltic Sea in the Pomeranian region. We examined the levels of Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Co, Cd, and Pb and compared ecophysiological determinations for developing storks. Blood samples of wing venous were collected from 91 chicks from 33 nests. The degree of activity of antioxidant enzymes studied has been different in White Stork chicks' blood from Poland regions, as a rule. We have stated a relatively high level of CAT, GPx, SOD, and GR activity and malondialdehyde (MDA) content in chicks from polluted areas. However, relative value for GR in storks from Odra meadows was considerably higher (about 112 nmol NADPH(2)/min ml) than those in chicks from other environments (56-84 nmol on average). Relatively high levels of CAT, CP, and GPx (2.7 mkM/min l, 22.2 mg/l, and 3.8 nmol GSH/min ml, respectively) were also stated in chicks nested in swamps near Baltic Sea. Simultaneously, we have stated differences (p0.02-p0.001) in the level of elements (besides Ca) in blood of young storks from the studied areas. We found a high level of toxic metals, e.g. Cd, either from swamps near Baltic Sea (2.7 mg/kg) or from Głogów smelter (2.2mg/kg), whilst Pb concentration was high in chicks from Głogów (7.2 mg/kg). Cd and Pb levels in blood of chicks were different in individuals from each region (p0.001). Birds from a smelter have the highest level of these elements, whereas the lowest one was stated in chicks from Odra meadows (Cd: 1.45, Pb: 0.84 mg/kg). Thus, Cd could be a useful marker of response for polluted stress. We also observed a relatively high level of Mg in chicks from both Pomeranian (7000 mg/kg) and polluted (about 6000 mg/kg) areas. Potassium, zinc, and cobalt levels were highest in chicks from suburbs (4.65, 10.1, and 2.7 mg/kg, respectively) and polluted regions (3.8, 9.7, and 5.6 mg/kg, respectively), whilst Cu and Mn were highest in those from polluted (10.9 and 47.6 mg/kg, respectively) and Pomeranian regions (11 and 42.2 mg/kg, respectively). Concentrations of Na, K, and Ca in chicks from Głogów smelter (143.2, 3.8, and 115.9 mg/kg, respectively) were often similar to those from Odra meadows (147.8, 3.6, and 112.5 mg/kg, respectively). This was probably due to a similar degree of homeostatic regulations of an organism. The levels of Mg, Fe, Zn, and Cu were often different (p0.02-p0.001) in the blood of White Stork chicks from the studied areas. Co, Pb, and Cd levels were higher (p0.001) in chicks from Głogów smelter than in those from Odra meadows. It is evidence for importance of anthropopression, which influenced the course of biogeochemical processes and the bioaccumulation of toxic metals locally. This takes place also in chicks from swamps near Baltic Sea, in which the level of Cd was high (2.7 mg/kg); so we can state the high intensity of intoxication in this region. We can conclude that the use of hematological research assesses the condition of birds and might give a positive association with miscellaneous environmental loads. The high concentration of toxic heavy metals involved greater intensity of antioxidant enzymes' activity. Environmental intoxication causes an increase of lipoperoxidation intensity in growing chicks and changes the response of their immunological system.

A series of model Schiff bases – 2,6-bis(alkylimino)phenol derivatives (Me, c-Pr, c-Bu, c-Pen and Ph) – has been studied by the solution and solid state (c-Pr and Ph derivatives) NMR methods. All compounds under investigations exhibit tautomeric equilibria in which proton is distributed between two imine sites. For the whole series, the strongest intramolecular H-bond is formed by the methyl derivative. The cycloaliphatic derivatives form weaker H-bonds. Their strength is proportional to the size of the aliphatic ring. The principal components of 15 N chemical shift anisotropy (CSA) tensor have been measured in the solid state for the cyclopropyl derivative. The first two principal components of the CSA tensor change in the same way with respects to hydrogen bond formation as the isotropic nitrogen chemical shift values. A relationship between the CSA principal components and structure of tautomers present in the system has been discussed. In chloroform solutions we also measured the coalescence temperatures to estimate the reaction rate and activation energy. For the c-Pr Schiff-base derivative, the X-ray structure has been established. This compound crystallizes in the monoclinic P 2 1 space group. There are two independent molecules in the crystal lattice. The geometry of the two moieties is very similar with the exception of some subtle changes in the intramolecular hydrogen bond and its vicinity. Although the molecules seem to be related by a glide plane, the symmetry is non-crystallographic and there is no indication of the existence of such a plane in the intensities of the reflections. We present details of the hydrogen bonds in both moieties.

Eight Schiff bases (N-(R-salicylidene)–cycloalkilamines, R=H, 5-NO2 and 5-Br) obtained from cyclopropyl, cyclobutyl- and cyclopentylamine were investigated in terms of intramolecular hydrogen bond formation in chloroform solution and in the solid state. The relationship between cycloalkyl ring size and proton position was discussed. For the compounds which exist as OH form (salicylaldehyde and 5-bromosalicylaldehyde derivatives), no correlation between ring size and proton position in hydrogen bond was found. For 5-nitro derivatives, the structure of hydrogen bridge strongly depends on the cycloaliphatic ring size.

In present work set of eight Schiff bases derived from substituted salicylaldehydes and aliphatic and aromatic amines has been studied in the solid state by 15 N and 13 C CPMAS NMR methods. 15 N CPMAS NMR measurement is especially useful for investigation of the tautomerism in the compounds considered, owing to the large difference in the nitrogen chemical shifts of OH and NH tautomers. In the solid state, four of the compounds examined were shown by 15 N CPMAS NMR to exist as OH tautomeric forms, and the remaining four as the corresponding NH forms with different stage of proton transfer process, from oxygen to nitrogen site. This was confirmed by 13 C CPMAS. The results reported were compared with those obtained for only two compounds in CDCl 3 solutions (solubility problems).

Three Schiff's bases and two Schiff–Mannich bases derivatives of 4-bromophenol were synthesised and studied by FT-IR and 1H, 13C, 15N NMR and CPMAS spectroscopy. For comparison the Schiff's base of 5-bromo-2-methoxy-benzaldehyde with pentafluoroaniline was also studied. The structures of Schiff's bases and the hydrogen bonds within these structures are discussed.

The 1 H, 13 C and 15 N NMR spectra of 4-bromo-6-diethylaminomethyl-2-R-iminomethyl-phenol have been recorded in CDCl 3 , in temperatures of 230–300 K. The presence of equilibrium between the two competitive OH⋯NCH 2 and OH⋯NC intramolecular hydrogen bonds has been found. The rotation of the OH group slows down at 230 K (in the NMR-time scale). Compound 1 (RNC 2 H 5 ) exists mainly with the OH group engaged in the intramolecular hydrogen bond to the imine-N atom (85%). The weakening the hydrogen bond by substitution of the N -alkyl by the N -aniline group (compound 2 ) increases the population of the Mannich type form (to 40%).

15 N NMR spectra of a series of N -(R-salicylidene)-alkylamines in CDCl 3 solution were measured. Proton transfer equilibrium has been established on the basis of the temperature dependence of the 15 N chemical shift and 1 J NH coupling constants.

The title compound in the solid state exists in the proton transfer − δ O⋯H–N + δ state. This is due, most probably, to the fact that dimeric species are formed that promotes more polar charge distribution. The studies performed in various non-polar and medium-polar solvents show that in such cases no proton transfer takes place. Only in very polar solvents like acetonitrile we are dealing with intramolecular ion-pairs. The ab initio calculations confirm such finding. The detailed vibrational analysis was performed based on ab initio calculations, Infrared (IR), Raman (R) and inelastic neutron scattering (INS) studies, over the whole frequency range. Of particular interest were the frequencies sensitive to the proton transfer with participation of the bridge atoms.

Two 3-diethylaminomethyl-5-R-salicylic aldehydes were obtained and studied in chloroform solutions by FTIR and NMR spectroscopy. The existence of an equilibrium between the structures with OH⋯OC and N⋯HO intramolecular hydrogen bonds was suggested. In the case of compound 1 (R=OCH3) the OH⋯OC intramolecular hydrogen bond was more favorable whereas in the case of compound 2 (R=Br) the structure with the OH⋯N intramolecular hydrogen bond was predominant.

Background: Reductions in global longitudinal strain (GLS) may be observed prior to the onset of systolic dysfunction in patients receiving trastuzumab and anthracycline agents and has been targeted as a method of early detection of cardiotoxicity. Data on cardiotoxicity in the setting of non

A new mixed finite element method is presented that has improved numerical stability and has similar numerical accuracy compared to the EVSS/FEM developed by Rajagopalan et al. (J. Non-Newtonian Fluid Mech. 36 (1990) 159–192). The new method, denoted EVSS-G/FEM, is based on separate bilinear interpolation of all relevant components of the velocity gradient tensor. Lagrangian bilinear approximations of this variable are formed by least-squares interpolation of the derivatives of a Lagrangian biquadratic approximation to the velocity field that is generated by solution of the momentum and continuity equations using a standard mixed formulation for velocity and pressure. Elastic components of the stress are computed by solving the constitutive equation using either the streamline upwinding (SU) or streamline upwind Petrov-Galerkin (SUPG) methods with bilinear interpolation. The motivation for the interpolation of the velocity gradients and for the stress interpolation is to force the compatibility between these variables that is needed to satisfy differential viscoelastic constitutive equations in the limit where the velocity field vanishes, as it does near solid boundaries. The enhanced numerical stability of the EVSS-G/FEM over the EVSS/FEM formulation is demonstrated for the calculation of the linear stability of planar Couette flow of a UCM fluid, where closed form results exist for the linear stability of the steady-state flow; hence, any instability detected in the numerical solution is a result of either the finite element approximation or the time integration method. The second possibility is eliminated by using a fully implicit time integration method. Calculations with the EVSS-G/FEM are stable for De >100, whereas calculations with the EVSS/FEM become numerically unstable for De >5. The EVSS-G formulation is combined with finite element discretizations that incorporate local adaptive mesh refinement for increasing the accuracy of the calculations in regions where the stress and velocity gradients change rapidly. The accuracy of the EVSS-G/FEM is demonstrated by steady-state calculations for the flow between eccentric rotating cylinders, flow through a wavy-walled tube, and for flow through a square array of cylinders; each has been used before as a test problem for the accuracy of viscoelastic flow calculations. As in previous calculations, discretization of the constitutive equation by SUPG gives superior accuracy at high values of De compared to the application of SU.

A sample of xenon enriched in 136Xe has been obtained with the ultracentrifuge system of the United States Department of Energy in Oak Ridge, Tennessee. The same system has also been used for cleanup only, namely to eliminate undesired gas impurities. Measurements of radioactivity carried out with a multicell proportional chamber show that ultracentrifugation is indeed very effective in the elimination of krypton.