HDL-C and HDL-C/ApoA-I predict long-term progression of glycemia in established type 2 diabetes

OBJECTIVE: Low HDL cholesterol (HDL-C) and small HDL particle size may directly promote hyperglycemia. We evaluated associations of HDL-C, apolipoprotein A-I (apoA-I), and HDL-C/apoA-I with insulin secretion, insulin resistance, HbA1c, and long-term glycemic deterioration, reflected by initiation of pharmacologic glucose control.

RESEARCH DESIGN AND METHODS: The 5-year Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study followed 9,795 type 2 diabetic subjects. We calculated baseline associations of fasting HDL-C, apoA-I, and HDL-C/apoA-I with HbA1c and, in those not taking exogenous insulin (n = 8,271), with estimated β-cell function (homeostasis model assessment of β-cell function [HOMA-B]) and insulin resistance (HOMA-IR). Among the 2,608 subjects prescribed lifestyle only, Cox proportional hazards analysis evaluated associations of HDL-C, apoA-I, and HDL-C/apoA-I with subsequent initiation of oral hypoglycemic agents (OHAs) or insulin.

RESULTS: Adjusted for age and sex, baseline HDL-C, apoA-I, and HDL-C/apoA-I were inversely associated with HOMA-IR (r = -0.233, -0.134, and -0.230; all P < 0.001; n = 8,271) but not related to HbA1c (all P > 0.05; n = 9,795). ApoA-I was also inversely associated with HOMA-B (r = -0.063; P = 0.002; n = 8,271) adjusted for age, sex, and HOMA-IR. Prospectively, lower baseline HDL-C and HDL-C/apoA-I levels predicted greater uptake (per 1-SD lower: hazard ratio [HR] 1.13 [CI 1.07-1.19], P < 0.001; and HR 1.16 [CI 1.10-1.23], P < 0.001, respectively) and earlier uptake (median 12.9 and 24.0 months, respectively, for quartile 1 vs. quartile 4; both P < 0.01) of OHAs and insulin, with no difference in HbA1c thresholds for initiation (P = 0.87 and P = 0.81). Controlling for HOMA-IR and triglycerides lessened both associations, but HDL-C/apoA-I remained significant.

CONCLUSIONS: HDL-C, apoA-I, and HDL-C/apoA-I were associated with concurrent insulin resistance but not HbA1c. However, lower HDL-C and HDL-C/apoA-I predicted greater and earlier need for pharmacologic glucose control.

Comparative growth rates and internal banding periodicity of maerl species (Corallinales, Rhodophyta) from northern Europe

Maerl is a type of rhodolith, found in ecologically important beds of high conservation value; a major conservation objective is to establish growth rates. Maerl shows internal banding of controversial periodicity that may contain a high-resolution record of palaeoceanographic-palaeoclimatic data. To investigate growth rates and banding periodicity, we used the vital stain Alizarin Red in combination with scanning electron microscopy (SEM). Three maerl species, Phymatolithon calcareum, Lithothamnion corallioides and L. glaciale, were collected from maerl beds in Ireland. Following staining, maerl was grown in three controlled temperature treatments and at two depths in the field (P. calcareum only), with Corallina officinalis as a control for the stain. Alizarin Red was shown to be a suitable marker for growth in European maerl species and for C. officinalis. The average tip growth rate of P. calcareum from Northern Ireland at 10 m depth and under constant laboratory conditions was c. 0.9 mm yr(-1), double the rates observed at 5 m depth and in L. corallioides. Our measurements and re-examination of reported data allow us to conclude that the three most abundant maerl species in Europe grow about 1 (0.5-1.5) mm per tip per year under a wide range of field and artificial conditions. Internal banding in temperate European maerl revealed by SEM is a result of regular changes in wall thickness; the approximately monthly periodicity of bands in field-grown specimens is consistent with previous suggestions that they may be lunar. The potential for maerl banding to be a high-resolution record of palaeoclimatic and palaeoenvironmental change could be realized with this vital stain in conjunction with isotopic or microgeochemical analyses.

Grazing under experimental hypercapnia and elevated temperature does not affect the radula of a chiton (Mollusca, Polyplacophora, Lepidopleurida)

Chitons (class Polyplacophora) are benthic grazing molluscs with an eight-part aragonitic shell armature. The radula, a serial tooth ribbon that extends internally more than half the length of the body, is mineralised on the active feeding teeth with iron magnetite apparently as an adaptation to constant grazing on rocky substrates. As the anterior feeding teeth are eroded they are shed and replaced with a new row. The efficient mineralisation and function of the radula could hypothetically be affected by changing oceans in two ways: changes in seawater chemistry (pH and pCO(2)) may impact the biomineralisation pathway, potentially leading to a weaker or altered density of the feeding teeth; rising temperatures could increase activity levels in these ectothermic animals, and higher feeding rates could increase wear on the feeding teeth beyond the animals' ability to synthesise, mineralise, and replace radular rows. We therefore examined the effects of pH and temperature on growth and integrity in the radula of the chiton Leptochiton asellus. Our experiment implemented three temperature (similar to 10, 15, 20 degrees C) and two pCO(2) treatments (similar to 400 mu atm, pH 8.0; similar to 2000 mu atm, pH 7.5) for six treatment groups. Animals (n = 50) were acclimated to the treatment conditions for a period of 4 weeks. This is sufficient time for growth of ca. 7-9 new tooth rows or 20% turnover of the mineralised portion. There was no significant difference in the number of new (non-mineralised) teeth or total tooth row count in any treatment. Examination of the radulae via SEM revealed no differences in microwear or breakage on the feeding cusps correlating to treatment groups. The shell valves also showed no signs of dissolution. As a lineage, chitons have survived repeated shifts in Earth's climate through geological time, and at least their radulae may be robust to future perturbations.

Rates of E1, E2, M1, and M2 transitions in Ni II

Aims. We present rates for all E1, E2, M1, and M2 transitions among the 295 fine-structure levels of the configurations 3d⁹, 3d⁸4s, 3d⁷4s², 3d⁸4p, and 3d⁷4s4p, determined through an extensive configuration interaction calculation. 

Methods. The CIV3 code developed by Hibbert and coworkers is used to determine for these levels configuration interaction wave functions with relativistic effects introduced through the Breit-Pauli approximation. 

Results. Two different sets of calculations have been undertaken with different 3d and 4d functions to ascertain the effect of such variation. The main body of the text includes a representative selection of data, chosen so that key points can be discussed. Some analysis to assess the accuracy of the present data has been undertaken, including comparison with earlier calculations and the more limited range of experimental determinations. The full set of transition data is given in the supplementary material as it is very extensive. 

Conclusions. We believe that the present transition data are the best currently available.

Differential Scanning Calorimetry Study and Computer Modeling of b a Phase Transformation in Ti-6Al-4V Alloy

The relationship between heat-treatment parameters and microstructure in titanium alloys has so far been mainly studied empirically, using characterization techniques such as microscopy. Calculation and modeling of the kinetics of phase transformation have not yet been widely used for these alloys. Differential scanning calorimetry (DSC) has been widely used for the study of a variety of phase transformations. There has been much work done on the calculation and modeling of the kinetics of phase transformations for different systems based on the results from DSC study. In the present work, the kinetics of the transformation in a Ti-6Al-4V titanium alloy were studied using DSC, at continuous cooling conditions with constant cooling rates of 5 °C, 10 °C, 20 °C, 30 °C, 40 °C, and 50 °C/min. The results from calorimetry were then used to trace and model the transformation kinetics in continuous cooling conditions. Based on suitably interpreted DSC results, continuous cooling–transformation (CCT) diagrams were calculated with lines of isotransformed fraction. The kinetics of transformation were modeled using the Johnson–Mehl–Avrami (JMA) theory and by applying the "concept of additivity." The JMA kinetic parameters were derived. Good agreement between the calculated and experimental transformed fractions is demonstrated. Using the derived kinetic parameters, the transformation in a Ti-6Al-4V alloy can be described for any cooling path and condition. An interpretation of the results from the point of view of activation energy for nucleation is also presented.

Rates of childhood trauma in a sample of patients with schizophrenia as compared with a sample of patients with non-psychotic psychiatric diagnoses

Despite strong evidence of high rates of childhood and adult trauma in schizophrenia, the area remains under-researched. Our objectives in the study were first, to examine the rates of exposure to childhood, adult and lifetime (child plus adult) trauma in a population with schizophrenia and a population with non-psychotic psychiatric diagnoses and second, to examine the effect of trauma on the symptoms of schizophrenia. Two groups, those with schizophrenia (n = 40), and those with a non-psychotic diagnosis (n = 30), were recruited. Data were collected for demographic, psychiatric and trauma histories for all participants and on psychosocial functioning and psychiatric symptomatology for the patients with schizophrenia. Childhood exposure to trauma was significantly more common in the schizophrenia group (t = 5.196, df = 68, p <0.001, Eta squared = 0.28), with the strongest relationship being childhood physical assault. In the schizophrenia group a history of trauma was significantly related to poor communication skills (r = -0.529, p <0.001) and depressive symptoms (r = 0.443, p = 0.004). Evidence that childhood exposure to trauma is more common in a population with schizophrenia is consistent with other studies and raises the possibility that such trauma is of etiological importance. Further research is required to replicate those findings, to elucidate possible pathways by which the experience of trauma may contribute to the development of schizophrenia, and to explore the relationship between a history of childhood trauma and the experience of depressive symptoms in schizophrenia.

Neural modelling, control and optimisation of an industrial grinding process

This paper describes the development of neural model-based control strategies for the optimisation of an industrial aluminium substrate disk grinding process. The grindstone removal rate varies considerably over a stone life and is a highly nonlinear function of process variables. Using historical grindstone performance data, a NARX-based neural network model is developed. This model is then used to implement a direct inverse controller and an internal model controller based on the process settings and previous removal rates. Preliminary plant investigations show that thickness defects can be reduced by 50% or more, compared to other schemes employed. (c) 2004 Elsevier Ltd. All rights reserved.

Phenotypic diversity amongst strains of Pleurotus sajor-caju: implications for cultivation in and environments

In arid regions, biodiversity and biomass are limited by water availability, and this problem has been compounded by desertification associated with global climate change. The saprotrophic macrofungi that are indigenous to hot subtropical and tropical regions, such as Pleurotus spp., can play key roles in water sequestration, nutrient cycling, human nutrition, and bioremediation of waste materials. We studied 15 strains of Pleurotus sajor-caju, a widespread and phenotypically-diverse species, to establish variability in growth response and primordium development over a range of stress parameters: osmotic potential (-0.5 to -5 MPa), temperature (5-40 degrees C) and pH (2-12). The initiation of primordia precedes basidiome production and therefore represents a key stage in bioremediation strategies and fungi-driven nutrient cycles. Primordia were produced at low pH (4-6), at suboptimal growth temperatures (<or =25 degrees C), and under moderate water stress (-0.5 to -3.5 MPa). Although the growth windows for different strains were similar, their maximum growth rates and the optimum conditions for growth varied. We discuss the phenotypic diversity of Pleurotus strains and discuss their potential for cultivation, bioremediation and ecological regeneration.

Uptake of carbon, nitrogen and phosphorus by phytoplankton along the 20 degrees W meridian in the NE Atlantic between 57.5 degrees N and 37 degrees N

Phytoplankton biomass and rate of production were measured along a transect from 57.54 degreesN to 37.01 degreesN in the northeast Atlantic during July 1996 and at a series of stations over a 7-day period at 37 degreesN 20 degreesW. Surface nutrient concentrations ranged from 4 mu mol l(-1) NO3-, and 0.35 mu mol l(-1) PO43- at 57.54 degreesN to <10 nmol l(-1) NO3- and similar to 10 nmol l(-1) PO43- at 37.01 degreesN. The greatest phytoplankton biomass and production were measured in the vicinity of a frontal system at 50 degreesN, and there was a general decline in total phytoplankton biomass and production to the south of the transect. Production was measured in three size fractions. At the station with the highest chlorophyll concentrations (50.34 degreesN), phytoplankton cells larger than 5 mum dominated the assemblage, accounting for 72% of the chlorophyll concentration (22.9 mg m(-2)) and 51% of primary production (54.1 mmol Cm-2 d(-1)), but picophytoplankton production was also high (43%). At 57 degreesN, carbon fixation by the > 5 mum fraction accounted for 75% of the daily production of 60.75 mmol Cm-2 d(-1). At 37 degreesN, picophytoplankton was the dominant group, accounting for similar to 58% (10 mg m(-2)) of chlorophyll and similar to 64% (46 mmol Cm-2 d(-1)), of primary production. Nitrate, ammonium and phosphate uptake rates also were determined. Although high nitrate uptake rates were measured in the surface water at similar to 50 degreesN, the greatest uptake rates of both depth-integrated nitrate and ammonium were at the south of the transect. At 37 degreesN, a deep euphotic zone was present and light penetrated through the nitracline; total nitrate uptake was enhanced because of assimilation at the base of the euphotic zone. As a consequence, high values of depth-integrated f-ratio were measured in the oligotrophic waters at the south of the transect. Phosphate was predominantly incorporated into the picoplankton fraction, which included heterotrophic and autotrophic components, at all stations and a significant proportion of phosphate uptake occurred in the dark. The C:N:P assimilation ratios were variable throughout the region; phosphate uptake was generally greater than would be expected if nutrient assimilation were in proportion to the Redfield ratio. (C) 2001 Elsevier Science Ltd. All rights reserved.

Comparisons of plankton at 59 degrees N and 37 degrees N during two Lagrangian drift experiments in the North Atlantic in June and July 1996

Data are summarised for two Lagrangian experiments in the North Atlantic in early summer 1996. At 59 degreesN 20 degreesW, plankton dynamics was studied in an SF, tracer release experiment within a mesoscale eddy over a 9-day period. At 37 degreesN 20 degreesW, a second experiment followed a drifting buoy for 7 days. The data obtained in these two experiments have been averaged for 3 depth strata; the euphotic zone, the surface mixed layer (SML), and the seasonal thermocline immediately beneath the surface mixed layer. At 59 degreesN, the euphotic zone was only marginally deeper than the SML, but at 37 degreesN the SML was ca 30 m and the euphotic depth was ca 110 m. At 37 degreesN, nutrient concentrations in the SML were low but significant new production occurred in the thermocline because of light penetration into the nutricline. The particulate organic carbon (POC) concentration of the SML at 59 degreesN was 13-15 mu mol C kg(-1), but at 37 degreesN POC concentrations were 4 mu mol C kg(-1). These POC measurements include biota and detritus. As a way of investigating latitudinal differences in the plankton communities, estimates have been made of the carbon and nitrogen content of phytoplankton, bacterioplankton, microzooplankton and mesozooplankton. At both 59 degreesN and 37 degreesN, phytoplankton was the largest component, accounting for ca 50% of the planktonic biomass in the SML. At 59 degreesN, microzooplankton was 16% of the planktonic carbon, but at 37 degreesN this reduced to 8% of the total. Mesozooplankton was a relatively constant proportion (ca 20%) of the planktonic carbon in the SML at both 59 degreesN and 37 degreesN. Bacterioplankton was 14% of the biomass at 59 degreesN, increasing to 24% in the microbial loop-dominated system at 37 degreesN. Mean carbon fixation rate in the oligotrophic southern station was 24% of that at the north, with more carbon fixation below the SML at 37 degreesN than at 59 degreesN. Respiration rates showed little variation with latitude, and the rates at 37 degreesN were 80% of those at 59 degreesN. Nitrate and ammonium uptake rates were very low in the oligotrophic conditions in the SML at 37 degreesN, but nitrate uptake in the euphotic zone was comparable to that at 59 degreesN. Ammonium uptake by phytoplankton was also significantly greater at 37 degreesN, in both the euphotic zone and thermocline, but uptake in the SML was only 20% of that in the SML at 59 degreesN. (C) 2001 Elsevier Science Ltd. All rights reserved.

The electrochemical oxidation and reduction of nitrate ions in the room temperature ionic liquid [C(2)mim][NTf2]; the latter behaves as a 'melt' rather than an 'organic solvent'

The electrochemical oxidation of 1-butyl-3-methylimidazolium nitrate [C(4)mim][NO3] was studied by cyclic voltammetry in the room temperature ionic liquid (RTIL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [C(2)mim][NTf2]. A sharp peak was observed on a Pt microelectrode (d = 10 mu m), and a diffusion coefficient at infinite dilution of ca. 2.0 x 10(-11) m(2) s(-1) was obtained. Next, the cyclic voltammetry of sodium nitrate (NaNO3) and potassium nitrate (KNO3) was studied, by dissolving small amounts of solid into the RTIL [ C2mim][ NTf2]. Similar oxidation peaks were observed, revealing diffusion coefficients of ca. 8.8 and 9.0 x 10(-12) m(2) s(-1) and solubilities of 11.9 and 10.8 mM for NaNO3 and KNO3, respectively. The smaller diffusion coefficients for NaNO3 and KNO3 (compared to [C(4)mim][NO3]) may indicate that NO3- is ion-paired with Na+ or K+. This work may have applications in the electroanalytical determination of nitrate in RTIL solutions. Furthermore, a reduction feature was observed for both NaNO3 and KNO3, with additional anodic peaks indicating the formation of oxides, peroxides, superoxides and nitrites. This behaviour is surprisingly similar to that obtained from melts of NaNO3 and KNO3 at high temperatures ( ca. 350 - 500 degrees C), and this observation could significantly simplify experimental conditions required to investigate these compounds. We then used X-ray photoelectron spectroscopy (XPS) to suggest that disodium( I) oxide (Na2O), which has found use as a storage compound for hydrogen, was deposited on a Pt electrode surface following the reduction of NaNO3.

A quantitative determination of reaction mechanisms from density functional theory calculations: Fischer-Tropsch synthesis on flat and stepped cobalt surfaces

We systematically investigated the mechanism of the C-1 + C-1 coupling reactions using density functional theory. The activation energies of C-1 + C-1 coupling and carbon hydrogenation reactions on both flat and stepped surfaces were calculated and analyzed. Moreover, the coverages of adsorbed C-1 species were estimated, and the reaction rates of all possible C-1 + C-1 coupling pathways were quantitatively evaluated. The results suggest that the reactions of CH2 + CH2 and CH3 + C at steps are most likely to be the key C-1 + C-1 coupling steps in FT synthesis on Co catalysts. The reactions of C-2 + C-1 and C-3 + C-1 coupling also were studied; the results demonstrate that in addition to the pathways of RCH + CH2 and RCH2 + C, the coupling of RC + C and RC + CH also may contribute to the chain growth after C-1. (C) 2008 Elsevier Inc. All rights reserved.

Absolute configuration assignment and enantiopurity determination of chiral alkaloids and coumarins derived from O- and C-prenyl epoxides

A combination method of ozonolysis and chiral stationary phase (CSP)-GC-MS analysis has been developed to determine the enantiopurity values and absolute configurations of a range of alkaloid and coumarin hemiterpenoids derived from C- and O-prenyl epoxides.

Volatile and persistent real exchange rates with or without sticky prices

The flexible-price two-country monetary model is extended to include a consumption externality with habit persistence. Two methodologies are employed to explore this model's ability to generate volatile and persistent exchange rates. In the first, actual data is used for the exogenous driving processes. In the second, the model is simulated using estimated forcing processes. The theory, in both cases, is capable of explaining the high volatility and persistence of real and nominal exchange rates as well as the high correlation between real and nominal rates. © 2007 Elsevier B.V. All rights reserved.

Energy levels, radiative rates, and electron impact excitation rates for transitions in OVII

Aims.
In this paper we report calculations for energy levels, radiative rates, and electron impact excitation rates for transitions in O vii.
Methods.
The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative
rates. For determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) and the
flexible atomic code (fac) are used.
Results.
Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest
49 levels of O vii. Collision strengths have been averaged over a Maxwellian velocity distribution, and the resulting effective collision
strengths are reported over a wide temperature range below 2 × 106 K. Additionally, lifetimes are also listed for all levels.
Key words.