Spin transition zone in Earth's lower mantle

Mineral properties in Earth's lower mantle are affected by iron electronic states, but representative pressures and temperatures have not yet been probed. Spin states of iron in lower-mantle ferropericlase have been measured up to 95 gigapascals and 2000 kelvin with x-ray emission in a laser-heated diamond cell. A gradual spin transition of iron occurs over a pressure-temperature range extending from about 1000 kilometers in depth and 1900 kelvin to 2200 kilometers and 2300 kelvin in the lower mantle. Because low-spin ferropericlase exhibits higher density and faster sound velocities relative to the high-spin ferropericlase, the observed increase in low-spin (Mg,Fe)O at mid-lower mantle conditions would manifest seismically as a lower-mantle spin transition zone characterized by a steeper-than-normal density gradient.     

Determination and depletion of residues of carbadox, tylosin, and virginiamycin in kidney, liver, and muscle of pigs in feeding experiments

The results of residue determinations of the growth promotors carbadox, tylosin, and virginiamycin in kidney, liver, and muscle from pigs in feeding experiments are described as well as the analytical methods used. Residues of the carbadox metabolite quinoxaline-2-carboxylic acid were found in liver from pigs fed 20 mg/kg in the diet with a withdrawal time of 30 days. No residues were detected in muscle with zero withdrawal time. The limit of determination was 0.01 mg/kg for both tissues. No residues of virginiamycin and tylosin were found in pigs fed 50 and 40 mg/kg, respectively, in the diet, even with zero withdrawal time. Residues of tylosin of 0.06 mg/kg and below were detected in liver and kidney from pigs fed 200 or 400 mg/kg and slaughtered within 3 h after the last feeding.     

Effects of lactoferrin, phytic acid, and EDTA on oxidation in two food emulsions enriched with long-chain polyunsaturated fatty acids

The influence of the addition of metal chelators on oxidative stability was studied in a milk drink and in a mayonnaise system containing highly polyunsaturated lipids. Milk drinks containing 5% (w/w) of specific structured lipid were supplemented with lactoferrin (6-24 muM) and stored at 2 degrees C for up to 9 weeks. Mayonnaise samples with 16% fish oil and 64% rapeseed oil (w/w) were supplemented with either lactoferrin (8-32 muM), phytic acid (16-124 muM), or EDTA (16-64 muM) and were stored at 20 degrees C for up to 4 weeks. The effect of the metal chelators was evaluated by determination of peroxide values, secondary volatile oxidation products, and sensory analysis. Lactoferrin reduced the oxidation when added in concentrations of 12 muM in the milk drink and 8 muM in the mayonnaise, whereas it was a prooxidant at higher concentrations in both systems. In mayonnaise, EDTA was an effective metal chelator even at 16 muM, whereas phytic acid did not exert a distinct protective effect against oxidation. The differences in the equimolar effects of the metal chelators are proposed to be due to differences in their binding constants to iron and their different stabilities toward heat and low pH.     

Space,Time, and Local Employment Growth: An Application of Spatial Regression Analysis

ABSTRACT Local and regional employment growth is generally studied either by searching for local qualitative explanatory factors such as governance, synergy between firms, and milieu effects, or by searching for general growth factors using statistical techniques. The body of work that relies on this approach has tended, in keeping with economics’ nomothetic tradition, to assume that local and regional growth factors are constant over space. The focus of this paper is on exploring the spatial stationarity of employment growth factors in Canada, but it also seeks to clarify some of the broad principles behind spatial regression techniques in order to provide a point of entry and a conceptual framework for empirical researchers. To do so, we apply a recently developed technique, Geographically Weighted Regression (GWR), and we explore the method's advantages and limits for answering our research question. We find evidence that growth factors differ across Canada, but we also conclude that the GWR technique, given the number and shape of regions available for our analysis and given certain limitations that are currently inherent to the method, can only provide tentative and exploratory results.     

Congenital hypothyroidism in Scottish Deerhound puppies

Two Scottish Deerhound puppies had clinical and pathological features consistent with the diagnosis of congenital non-goitrous hypothyroidism. They were from separate litters, but were the progeny of the same sire and dam. The puppies were smaller, had shorter limbs and shorter, broader heads than their littermates. They also had histories of weakness, difficulty in walking and somnolence. A characteristic radiographic feature was the absence of epiphyseal growth centres. Both had depressed serum thyroxine (T4) levels and one did not respond to exogenous thyroid stimulating hormone. On necropsy, the thyroid glands were small, the follicles varied in size and contained little or no colloid. The adenohypophysis contained many cells with markedly vacuolated cytoplasm. It is suggested that the clinicopathological pattern is the result of a primary thyroid abnormality. Possible mechanisms include either primary thyroid hypoplasia or an unresponsiveness to thyroid stimulating hormone.     

Synthesis and insecticidal properties of derivatives of propane-1, 3-dithiol (analogues of the insecticidal derivatives of dithiolane and trithiane from the alga Chara globularis Thuillier)

Functional derivatives of 2-(methylthio)propane-1, 3-dithiol (open chain analogues of the insecticidal 4-methyithio-1, 2-dithiolane and 5-methylthio-1, 2, 3-trithiane from the alga Chara globularis) possess insecticidal properties similar to those of the structurally related nereistoxin. Some derivatives of propane-1, 3-dithiol, bearing 2-substituents different from the methylthio group, have also been shown to have insecticidal pioperties.     

Herbicide perfluidone (1,1,1-trifluoro-N-[2-methyl-4-(phenylsulfonyl)phenyl]methanesulfonamide): Its metabolism in rats and chickens

Rats and chickens were each given a single oral dose (10 or 100 mg/kg body wt) of 1,1,1-trifluoro-N-[2-methyl-4-(phenylsulfonyl)phenyl-¹⁴C(U)]methanesulfonamide ([¹⁴C]perfluidone). Depending on the size of the dose, from 8.4 to 36.2% of the [¹⁴C] was eliminated in the urine and from 36.4 to 85.4% was eliminated in the feces within 48 hr after dosing. Less than 1% of the [¹⁴C] given to laying hens as [¹⁴C]perfluidone was present in the eggs produced during the first 96 hr after dosing. The percentage of the administered [¹⁴C] that remained in these animals (body with G.I. tract and contents removed) varied from 0.34 (96 hr after dosing) to 1.68% (48 hr after dosing). ¹⁴C-labeled compunds in the urine and feces from the rats and chickens were purified by solvent extraction, column chromatography, and gas-liquid chromatography, and then identified by infrared and mass spectrometry. The parent compound was the major ¹⁴C-labeled component in the urine and feces of both animals. 1,1,1-Trifluoro-N-[2-methyl-4-(3-hydroxyphenylsulfonyl)phenyl]methanesulfonamide was present in the feces of both animals. The proposed structures of other metabolites were 1,1,1-trifluoro-N-hydroxy-N-[2-methyl-4-(phenylsulfonyl)phenyl]methanesulfonamide (rat urine) and 1,1,1-trifluoro-N-{2-methyl-4-[(methylsulfonyl)-phenylsulfonyl]phenyl}methanesulfonamide (chicken urine).     

Spatial variability in the mineralisation of the phenylurea herbicide linuron within a Danish agricultural field: multivariate correlation to simple soil parameters

The spatial variability in the mineralisation rate of linuron [N-(3,4-dichlorophenyl)-N'-methoxy-N'-methylurea] was studied within a previously treated Danish agricultural field by sampling soils from eleven different plots randomly distributed across an area of 20 x 20 m. The soils were characterised with respect to different abiotic and biotic properties including moisture content, organic matter content, pH, nutrient content, bacterial biomass, potential for mineralisation of MCPA [(4-chloro-2-methylphenoxy)acetic acid] and linuron. Five soils had a potential for mineralisation of linuron, with 5-15% of the added [ring-U-14C]linuron metabolised to 14CO2 within 60 days at 10 degrees C, while no extensive mineralisation of linuron was observed in the six remaining soils within this period. A TLC analysis of the methanol-extractable residues showed no development of 14C-labelled metabolites from linuron in any of the samples. Multivariate analysis was conducted to elucidate relationships between the intrinsic properties of single soil samples and initial rate of linuron mineralisation. The analysis indicated that important soil parameters in determining the spatial heterogeneity included the C(total)/N(total) ratio, pH and the water-extractable potassium contents, with the first of these highly negatively correlated and the last two highly positively correlated to the initial linuron mineralisation rate. This study shows that enhanced biodegradation of linuron may develop with successive field treatments, but that considerable in-field spatial heterogeneity in the degradation rate still exists. Combined with a parallel enrichment study focused on the underlying microbial processes, the present results suggest that intrinsic soil properties affect the linuron-metabolising bacterial population and thereby determine the spatial variability in the linuron mineralisation activity.