Structure and dynamics of a 1,4-polybutadiene melt in an alumina nanopore: A molecular dynamics simulation.

We present results of molecular dynamics simulations of a chemically realistic model of 1,4-polybutadiene confined in a cylindrical alumina nanopore of diameter 10 nm. The simulations are done at three different temperatures above the glass transition temperature Tg. We investigate the density layering across the nanopore as well as the orientational ordering in the polymer melt, brought about by the confinement, on both the segmental and chain scales. For the chain scale ordering, the magnitude and orientation of the axes of the gyration tensor ellipsoid of single chains are studied and are found to prefer to align parallel to the pore axis. Even though double bonds near the wall are preferentially oriented along the pore walls, studying the nematic order parameter indicates that there is no nematic ordering at the melt-wall interface. As for the dynamics in the melt, we focus here on the mean-square-displacement of the monomers for several layers across the nanopore as well as the movement of the chain center of mass both of which display a slowing down of the dynamics in the layer at the wall. We also show the strong adsorption of the monomers to the pore wall at lower temperatures.

Role of torsional potential in chain conformation, thermodynamics, and glass formation of simulated polybutadiene melts.

For polymer chains, the torsional potential is an important intramolecular energy influencing chain flexibility and segmental dynamics. Through molecular dynamics simulations of an atomistic model for melts of cis-trans-1,4-polybutadiene (PBD), we explore the effect of the torsions on conformational properties (bond vector correlations and mean-square internal distances), fundamental thermodynamic quantities (density, compressibility, internal energy, and specific heat), and glass transition temperature Tg. This is achieved by systematically reducing the strength of the torsional potential, starting from the chemically realistic chain (CRC) model with the full potential toward the freely rotating chain (FRC) model without the torsional potential. For the equilibrium liquid, we find that the effect of the torsions on polymer conformations is very weak. Still weaker is the influence on the monomer density ρ and isothermal compressibility κT of the polymer liquid, both of which can be considered as independent of the torsional potential. We show that a van der Waals-like model proposed by Long and Lequeux [Eur. Phys. J. E 4, 371 (2001)] allows us to describe very well the temperature (T) dependence of ρ and κT. We also find that our data obey the linear relation between 1/kBTρκT and 1/T (with the Boltzmann constant kB) that has recently been predicted and verified on the experiment by Mirigian and Schweizer [J. Chem. Phys. 140, 194507 (2014)]. For the equilibrium liquid, simulations result in a specific heat, at constant pressure and at constant volume, which increases on cooling. This T dependence is opposite to the one found experimentally for many polymer liquids, including PBD. We suggest that this difference between simulation and experiment may be attributed to quantum effects due to hydrogen atoms and backbone vibrations, which, by construction, are not included in the classical united-atom model employed here. Finally, we also determine Tg from the density-temperature curve monitored in a finite-rate cooling process. While the influence of the torsional potential on ρ(T) is vanishingly small in the equilibrium liquid, the effect of the torsions on Tg is large. We find that Tg decreases by about 150 K when going from the CRC to the FRC model.

Validación de la versión española del Test de Ejercicio Compulsivo en varones universitarios: Análisis Factorial Confirmatorio y un estudio de invarianza / Validação da versão espahola do Teste de Exercício Compulsivo em estudantes universitários do sexo masculino: uma análise fatorial confirmatória e estudo da sua invariância / Validation of the Spanish Compulsive Exercise Test Version in Male University Students: A Confirmatory Factor Analysis and invariance study

Los varones son mas vulnerables a realizar conductas patológicas relacionadas con el ejercicio físico. El Cuestionario de Ejercicio Compulsivo (CET) es una de las medidas mas utilizadas sobre ejercicio patológico. Sin embargo, existen algunas inconsistencias con respecto a sus propiedades psicométricas, especialmente en muestras masculinas. El objetivo fue evaluar las propiedades psicométricas de la versión española del CET en una muestra representativa de varones.Un total de 750 estudiantes universitarios varones respondieron al CET junto con el Inventario Revisado de Obsesividad-Compulsividad, Inventario de Trastorno Dismórfico Muscular y Cuestionario Internacional de Actividad Física. Para evaluar la estructura interna, se probaron dos modelos mediante Análisis Factorial Confirmatorio. Se estudió la invarianza de la escala en función del nivel competitivo, la consistencia interna, la validez convergente y concurrente.Los resultados no replicaron la estructura original de cinco factores. Por el contrario, se apoyó una solución de tres factores, así como la invarianza de la escala. La validez convergente y concurrente fue confirmada por la correlación con la sintomatología de dismorfia muscular, la obsesividad y el ejercicio físico vigoroso.La escala muestra buena consistencia interna.La versión española del CET es un instrumento fiable y válido, aunque se requiere de mayor investigación que aborde las cogniciones y conductas patológicas relacionadas con el ejercicio compulsivo, queafectan mayoritariamente a los varones. (AU)

Men are more vulnerable to engaging in pathological behaviors related to physical exercise. Compulsive Exercise Test (CET) is one of the most used measures of pathological exercise. However, there are some inconsistencies regarding their psychometric properties, especially in male samples. The aim was to psychometrically evaluate the Spanish version of the CET in a representative sample of Spanish males. A total 750 male university students answered to the CET together with the Obsessive-Compulsive Inventory Revised, Muscle Dysmorphic Disorder Inventory and International Physical Activity Questionnaire. To assess the internal structure, two models of the CET were tested by confirmatory factor analysis. Measurement invariance by competitive level, internal consistency, convergent and concurrent validity was also studied. Results did not replicate the original five-factor. In contrast, the three-factor solution was supported, as well as the measurement invariance. Convergent and concurrent validity was confirmed by correlations with muscle dysmorphia symptomatology, obsessiveness, and vigorous physical activity. Adequate levels of internal consistency were shown for the scale. The Spanish CET is a reliable and valid instrument although further research is required addressing specific problematic cognitions and behaviors related to compulsive exercise, which affects mainly males. (AU)

Os varões são mais vulneráveis a comportamentos patológicos relacionados com o exercício físico. O Teste de Exercício Compulsivo (Compulsive Exercise Test, CET, em Inglês) é uma das medidas de exercício patológico mais amplamente utilizadas. Contudo, existem algumas inconsistências no que diz respeito às suas propriedades psicométricas, especialmente em amostras masculinas. O objetivo era avaliar as propriedades psicométricas da versão espanhola do CET numa amostra representativa de homens. 750 estudantes universitários varões responderam ao CET juntamente com o Inventário Obsessivo-Compulsivo Revisado, Inventário de Desordens Dismórficas Musculares e o Questionário Internacional de Actividade Física. Para avaliar a estrutura interna, dois modelos foram testados por Análise Confirmativa de Fatores. A invariância da escala também foi estudada em função do nível competitivo, da consistência interna, e da validade da convergência e concorrente. Os resultados não reproduziram a estrutura original de cinco fatores. Mas em vez disso, foi mostrada asolução de três fatores, bem como a invariância da escala. A validade convergente e simultânea foi confirmada pela correlação com a sintomatologia da dismorfia muscular, obsessividade e exercício físico vigoroso. A escala mostra uma boa consistência interna. A versão espanhola do CET é um instrumento fiável e válido, embora seja necessária mais investigação para abordar os comportamentos cognitivos e patológicos relacionados com o exercício compulsivo, que afetam sobretudo aos homens. (AU)

Clinical predictors of complications in patients with left-sided infective endocarditis: A retrospective study of 206 episodes.

PURPOSE: Early identification of specific patient subgroups at high risk of developing life-threatening infective endocarditis (IE) complications is of paramount importance. Better stratification may allow more intensive treatment of these patients and positively influences clinical outcomes. METHODS: We carried out a retrospective survey of consecutive left-sided IE adult patients, admitted over a 15-year period to two main tertiary care centres in the Czech Republic. RESULTS: Among a group of 196 patients (155 males; median age 64 years), a total of 206 left-sided IE episodes were identified. Perivalvular extension of infection was most frequently seen in prosthetic aortic valve endocarditis (OR 6.706, p<0.0001). Valve prolapse/perforation during IE episodes was significantly associated with mitral valve IE (OR 2.136, p=0.026) and vegetation length (OR 1.055, p=0.009). Septic shock was significantly related to two main risk factors: S. aureus infection (OR 8.459, p=<0.0001) and smoking (OR 8.403, p=0.001). Mitral valve IE with a vegetation length ≥13 mm was the strongest risk factor for this complication (OR 3.24, p=0.001), followed by S. aureus infection (OR 3.59, p=0.002). Finally, septic shock (OR 6.000, p=0.001) represented the most important risk factor of in-hospital mortality. CONCLUSIONS: This study provides the most detailed profile of complication predictors related to left-sided IE in Central Europe. Early individual stratification of IE related occurrence of complications might help to decrease extremely high morbidity and mortality of this disease (Tab. 5, Ref. 37).

Relaxation processes and glass transition of confined polymer melts: A molecular dynamics simulation of 1,4-polybutadiene between graphite walls.

Molecular dynamics simulations of a chemically realistic model for 1,4-polybutadiene in a thin film geometry confined by two graphite walls are presented. Previous work on melts in the bulk has shown that the model faithfully reproduces static and dynamic properties of the real material over a wide temperature range. The present work studies how these properties change due to nano-confinement. The focus is on orientational correlations observable in nuclear magnetic resonance experiments and on the local intermediate incoherent neutron scattering function, Fs(qz, z, t), for distances z from the graphite walls in the range of a few nanometers. Temperatures from about 2Tg down to about 1.15Tg, where Tg is the glass transition temperature in the bulk, are studied. It is shown that weakly attractive forces between the wall atoms and the monomers suffice to effectively bind a polymer coil that is near the wall. For a wide regime of temperatures, the Arrhenius-like adsorption/desorption kinetics of the monomers is the slowest process, while very close to Tg the Vogel-Fulcher-Tammann-like α-relaxation takes over. The α-process is modified only for z≤1.2 nm due to the density changes near the walls, less than expected from studies of coarse-grained (bead-spring-type) models. The weakness of the surface effects on the glass transition in this case is attributed to the interplay of density changes near the wall with the torsional potential. A brief discussion of pertinent experiments is given.

Dielectric α-relaxation of 1,4-polybutadiene confined between graphite walls : Molecular dynamics investigations through numerical simulations of polymer molecules relaxation.

We present results of Molecular Dynamics (MD) simulations of a chemically realistic model of 1,4-polybutadiene confined by crystalline graphite walls. The simulations cover a large range of temperatures from T ≈ 2T g to T ≈ 1.15T g, where relevant time scales are accessible using such computational methods. We investigate the dielectric relaxation close to the walls in comparison to the one in the center of the film, and study the latter as a function of the film thickness from the walls. The segmental dynamics in the film is slowed down close to the walls, in comparison to the bulk. In addition to the α-process, the relaxation exhibits an additional long time decay, the so-called wall desorption process. We focus here on the α-process and find no significant shift of the dielectric T g as a function of layer thickness, in agreement with recent dielectric experiments. These findings can be correlated with the importance of the dihedral dynamics for all relaxation processes in polymers, which is unaltered except for the first nanometer next to the walls.

The role of urinary aldosterone for the diagnosis of primary aldosteronism.

When diagnosing primary aldosteronism, the measurement of urinary aldosterone after oral sodium loading is one of the currently recommended confirmatory tests. The aim of the study was to assess the repeatability and interpretation of urinary aldosterone in patients examined for suspected primary aldosteronism. Sixty-four hypertensive patients with suspected primary aldosteronism were prospectively enrolled and examined according to the study protocol. After antihypertensive medications interfering with renin-angiotensin-aldosterone system were withdrawn for at least 2 weeks, the confirmatory testing was performed: oral sodium loading preceded the collection of 24-h urine sample and subsequent saline infusion test. The identical procedures were repeated after 2 weeks. The concordant results of both saline infusion tests served for confirmation/exclusion of primary aldosteronism. Forty-nine patients were included in data analysis. Primary aldosteronism was excluded in 16, and confirmed in 33 individuals. The repeatability of urinary aldosterone was evaluated in 44 patients: the difference of urinary aldosterone levels ranged between 1 and 88% (median 31%). Ninety-three urine samples from 49 patients were used to validate the interpretation of urinary aldosterone in respect to the diagnosis of primary aldosteronism made by saline infusion testing; 96% sensitivity was characterized by urinary aldosterone ≥19 nmol/day, and 96% specificity was associated with urinary aldosterone ≥92 nmol/day. In 22 (45%) patients, urinary aldosterone remained in the "gray" zone between 19 and 92 nmol/day in all provided samples. The estimation of urinary aldosterone excretion after oral sodium loading is associated with marked intraindividual variability, and significant number of inconclusive results.

Comparación in vitro del efecto del pulido en la morfología superficial de tres resinas compuestas / In vitro comparison of the effect of polishing the surface morphology three composites

Objetivos: El objetivo del presente estudio fue evaluar la morfolog¡a de las superficie de tres resinas compuestas de restauración directa Filtek Z 250 (3M), TetricCeram (Ivoclar-Vivadent) y Te Econom (Ivoclar-Vivadent) pulidas con el sistema de pulido Astropol (Ivoclar-Vivadent), dada la importancia de obtener superficies altamente estáticas y adecuadamente lisas que dificulten el acúmulo de placa bacteriana, la tinción de la restauración que pueda afectar el color y la salud bucal del paciente. Material y Métodos: Se evaluaron 15 espec¡menes, cinco de cada resina compuesta las cuales fueron pulidas con el sistema Astropol© para posteriormente obtener las medidas con el microscopio confocal de superficie y tras procesar los datos con el programa ArRUGa 2.0 y utilizar los par metros utilizados fueron el Ra, RMS, Skewness, Kurtosis, factor de Wenzel y dimensi¢n fractal. Los resultados fueron analizados con las pruebas de ANOVA de una sola v¡a y de Sheffe con un nivel de confianza del 0.05, los cuales indicaron que hab¡a una diferencia estad¡sticamente significativa en los par metros de rugosidad de las tres resinas. Resultados: En el presente estudio se encontró que la superficie más lisa fue la obtenida utilizando la resina Z-250-3M y el sistema de pulido Astropol-IvoclarVivadent. Conclusiones: La utilizacián de los par metros de rugosidad de forma y un instrumento como el microscopio confocal nos da mayor información del comportamiento de las rugosidades.

Objetives: In the present study were evaluated the surface’s morphology of three composed resin of direct recovery as Filtek z 250 (3M), Tetric Ceram (Ivoclar-Vivadent) an TeEconom (Ivoclar-Vivadent) They were polished with the Astropol polish system (Ivoclar-Vivadent) It will give the important to obtain an adequate high esthetic flat surgace into them which doesn’t let the accumulate of bacteria biofilm, meithendyling on the recovery, so that it can to change the color and the patient’s oral health. Material and Methods: They were evaluated 15 samples, five of each composed resin, so we proceed to polish the surfaces with Astropol system, for then to obtain the measure in the Confocal Microscope, the dates were proced throught ArRuga 2.0 program and use roughness parameters. The parameters used were Ra, RMS, Skewness, kurtosis, Wenzel factor and Fractal dimention, the results were analyzed by the Anova Test on one way and the Sheffe’s test, with the confidence’s level of 0.05 those indicated that there were a significant stadistict difference into the winkled state’s parameter of the three resin. Results: In the present study we found that followed the most flat surface was obtained throught of the used Filtek Z-250-3M resin and the Astropol-IvoclarVivadent polish system of this was obtained a good polish. Conclusions: We found is too important to obtained a good polish, so we found is too important parameter, of form and an instrument like Confocal microscope, it describes us the best conduct of the winkled states.

Analysis of local properties during a scratch test on a polymeric surface using molecular dynamics simulations.

This work demonstrates a possible route to connect a particle (chain) based understanding with continuum mechanical questions about contact mechanics. The bond orientation, chain conformation and stress field of a polymer film were analyzed during scratch tests (tangential contact) using a molecular dynamics (MD) simulation approach. Scratch tests with a conical tip at constant scratching velocity were simulated on linear amorphous polymer surfaces at various temperatures and roughnesses of the tip and for various interactions between the tip and the particles of the polymer chains. The second Legendre polynomial (computed for small domains around the tip) gave the bond orientation inside the polymer film during sliding of the tip. The gyration tensor (layer-resolved in the direction of the polymer film thickness) provided information about the conformation of the polymer chains. These results allowed us to argue in favor of Briscoe's hypothesis (thin film sheared vs. "bulk" compressive behavior) concerning the friction properties of the polymer surfaces. Finally, the first stress measurements of the virial stress tensor (in sub-boxes placed in the MD cell) revealed a complex combination between compressive hydrostatic pressure and shear stress, which may be interpreted as a complex sheared domain at the interface.

Size and surface effects in the magnetic properties of maghemite and magnetite coated nanoparticles.

An increasing number of promising applications for future technology is arising from size constraints in nanoparticles (NPs) and from the chemical manipulation of their surfaces. In this work, we analyse the finite-size and surface effects on polyacrylic acid-coated Fe(3)O(4) NPs and oleic acid-coated gamma-Fe(2)O(3) NPs by studying their magnetization curves at different temperatures. The measured thermal dependence of the saturation magnetization is no longer explained by the typical T(3/2) Bloch law, yielding higher values than those expected for its exponent. When incorporated in polymeric matrixes to form magnetic transparent nanocomposites, the oleic acid-coated gamma-Fe(2)O(3) NPs also deviate from Bloch's law, but following the opposite trend observed in free coated NPs.

Radiofrequency-induced thermal inactivation of Toxoplasma gondii oocysts in water.

Toxoplasma gondii, a ubiquitous parasitic protozoan, is emerging as an aquatic biological pollutant. Infections can result from drinking water contaminated with environmentally resistant oocysts. However, recommendations regarding water treatment for oocyst inactivation have not been established. In this study, the physical method of radiofrequency (RF) power was evaluated for its ability to inactivate T. gondii oocysts in water. Oocysts were exposed to various RF energy levels to induce 50, 55, 60, 70 and 80 degrees C temperatures maintained for 1 min. Post-treatment oocyst viability was determined by mouse bioassay with serology, immunohistochemistry and in vitro parasite isolation to confirm T. gondii infections in mice. None of the mice inoculated with oocysts treated with RF-induced temperatures of > or =60 degrees C in an initial experiment became infected; however, there was incomplete oocyst activation in subsequent experiments conducted under similar conditions. These results indicate that T. gondii oocysts may not always be inactivated when exposed to a minimum of 60 degrees C for 1 min. The impact of factors such as water heating time, cooling time and the volume of water treated must be considered when evaluating the efficacy of RF power for oocyst inactivation.

[Is confirmation of an adrenal adenoma in patients with primary aldosteronism sufficient for indication of adrenalectomy?]. / Je prukaz adenomu nadledviny u pacientu s primárním hyperaldosteronizmem dostatecný pro indikati adrenalektomie?

BACKGROUND: Primary aldosteronism is one of the most common forms of secondary arterial hypertension. Adrenalectomy is effective in patients with proven unilateral hypersecretion of aldosterone whereas pharmacotherapy is indicated in bilateral forms of the disease. We can meet the opinion that in patients with confirmed primary aldosteronism and finding ofsuprarenal adenoma > or = 1 cm on computed tomography (CT) scanning, adrenalectomy can be recommended without further investigation. On the other hand we can perform adrenal venous sampling (AVS) to prove unilateral overproduction of aldosterone. OBJECTIVES: To evaluate whether AVS is necessary in all patients with unilateral adenoma > or = 1 cm. METHODS: We analyzed data from patients with proven primary aldosteronism, CT finding of adenoma > or = 1 cm along with normal morphology of contralateral adrenal gland, and successfully performed AVS. RESULTS: Out of 107 patients with proven primary aldosteronism, indicated for AVS, we included 30 patients with CT finding of suprarenal adenoma > or = 1 cm along with normal morphology of contralateral adrenal gland and successful AVS. Unilateral overproduction of aldosterone was found only in 17 cases (56.7%), the results in remaining 13 patients (43.3%) did not confirm activity of adenoma. CONCLUSION: Our results support necessity of performing AVS in all patients with primary aldosteronism in whom surgical treatment is considered, CT confirmation ofan adenoma is insufficient in this indication.

Neurovascular compression: sympathetic activity in severe arterial hypertension.

Compression of the rostral ventrolateral medulla oblongata (RVLM) by an abnormally located artery is regarded as one possible cause of arterial hypertension. There exists a limited set of data suggesting that increased sympathetic activity in patients with RVLM compression may lead to arterial hypertension. Accordingly, we decided to assess the sympathetic activity in patients with severe arterial hypertension and to investigate any correlation with the presence of RVLM compression. Sixty-four patients with severe arterial hypertension were enrolled in our study. Sympathetic activity was evaluated using 24-hour urinary norepinephrine as measured by high-pressure liquid chromatography with electrochemical detection. The presence of RVLM compression was assessed with magnetic resonance imaging. Neurovascular compression of the RVLM was identified in 40 patients, 27 of whom presented left-sided compression. Twenty-four hour urinary norepinephrine averaged 263.6+/-135.9 nmol in patients with neurovascular compression - 255.6+/-137.3 nmol in those with left-sided compression and 251.6+/-138.5 nmol in patients without RVLM compression. We did not identify any increase in urinary norepinephrine in patients with severe arterial hypertension and neurovascular compression of the RVLM. Our results do not support the hypothesis that neurovascular compression of RVLM may exhibit a sympathetically mediated increase in blood pressure.

Maghemite-silica nanocomposites: sol-gel processing enhancement of the magneto-optical response.

The preparation and processing of maghemite-silica gel nanocomposites have been investigated in order to maximize their magneto-optical response for magnetic field sensing applications. In situ precipitation of maghemite nanoparticles from an iron salt precursor during the sol-gel processing of the silica matrix has been carried out while controlling the time, temperature, and environment at each step of the whole process. In this paper, the nanostructural, magnetic, and magneto-optical properties of these materials are correlated with the processing path followed, from the starting sol to the partially densified monolith. Results demonstrate that introducing a washing treatment prevents the formation of hematite phase as well as an excessive particle agglomeration. Different processing conditions of identical sols may lead to nanocomposites with a Verdet constant at low magnetic fields (0.01 T) ranging from 200 to 950 rad T(-1) m(-1), which is the typical value of commercial terbium gallium garnets used in Faraday rotators.

[Current use of magnetic resonance imaging in cardiology]. / Soucasné moznosti zobrazení magnetickou rezonancí v kardiologii.

Magnetic resonance imaging is a modern imaging technique that is characterized by high resolution and variable tomographic slices. The development of magnetic resonance technology in last decade led to the expansion of this method in many fields of medicine. In cardiology, the imaging is focused on the heart, aorta, pulmonary, coronary and renal arteries. Dynamic imaging is used for the evaluation of the kinetics and the function of the ventricles. Static imaging serves for the assessment of the myocardial wall in patients with cardiomyopathies and coronary artery disease. The quality of static imaging can improve paramagnetic contrast agent that increasingly accumulates in areas of acute necrosis, fibrosis or infiltration of the myocardium. Magnetic resonance imaging can also diagnose intracardiac tumors and thrombi, valvular heart disease and pericardial disorders. Despite of wide spectrum of diagnostic applications, the clinical use of magnetic resonance imaging is reduced by limited availability and high cost of the examination.

Hyperglycaemic hyperosmolar nonketotic state as a cause of low gonadotrophin levels in postmenopausal diabetic women: a role for severe hypernatraemia.

Hypogonadotrophic hypogonadism is associated with uncontrolled diabetes mellitus. Hyperglycaemia is a unique metabolic abnormality of the hyperglycaemic hyperosmolar nonketotic state (HHNKS) and, as glucose availability regulates gonadotrophin release, we investigated whether gonadotrophin release is inhibited in diabetic women with HHNKS, and whether hyperglycaemia, hypernatraemia or both inhibit in vitro gonadotrophin-releasing hormone (GnRH) expression in GT1-7 neurones. Three groups of postmenopausal women were studied: nine diabetics with HHNKS, nine hospitalised ill nondiabetics and 15 healthy women. In addition, the effects of glucose (5.55, 33.3, 66.6 mmol/l) and sodium chloride (150 and 170 mmol/l) on GnRH expression were investigated using GT1-7 neurones. Postmenopausal diabetics with HHNKS showed a decrease in serum levels of luteinising hormone (diabetic HHNKS 2.2 +/- 0.9 IU/l versus ill nondiabetic 21.0 +/- 2.3 IU/l and healthy controls 20.9 +/- 2.8 IU/l, P < 0.01), follicle-stimulating hormone (diabetic HHNKS 8.2 +/- 2.1 IU/l versus ill nondiabetic 50.4 +/- 9.1 IU/l and controls 60.2 +/- 6.9 IU/l, P < 0.01) and free 3,5,3'-triiodothyronine (diabetic HHNKS 1.48 +/- 0.57 pmol/l versus ill nondiabetic 4.28 +/- 0.26 pmol/l and controls 3.88 +/- 0.11 pmol/l, P < 0.01). The plasma cortisol level was higher in both diabetic (985 +/- 130 nmol/l) and ill nondiabetic (726 +/- 52 nmol/l) women than in healthy women (512 +/- 47 nmol/l), but no differences were observed in plasma oestradiol, thyroid-stimulating hormone or free thyroxine. In vitro GT1-7 neurones expressed three-fold less GnRH at 170 mmol/l than at 150 mmol/l NaCl, whereas changing glucose concentrations in the culture medium did not affect GnRH expression. In conclusion, postmenopausal diabetic women with HHNKS show decreased serum gonadotrophin levels, and severe hypernatraemia may participate in the hypogonadotropism observed in HHNKS.

Thermal analysis in the evaluation of sediment pollution.

Characterization of organic matter in four sediments in the infuence area of wastewater discharges was carried out by both chemical and thermal analysis in order to assess their pollution level. Oxidisable organic carbon and organic matter were calculated by the standard methodology in laboratory. Thermogravimetry (TG), between 50 and 900 degrees C, was simultaneously performed in oxidizing conditions on ground sediments samples after three different pretreatments. Linear regression adjust of thermal analysis results versus chemical parameters provides the better Pearson's coefficients, leading to the best coefficients for weight loss in 250-400 degree C temperature range versus oxidisable organic carbon and organic matter at 360 degrees C, respectively. These results demonstrated the utility of thermoanalysis technique for the evaluation of the organic matter content of fresh sediments.

Disinfection of dairy and animal farm wastewater with radiofrequency power.

Radiofrequency (RF) power was investigated as a new, physical (nonchemical), thermal process to disinfect wastewater from dairy and animal facilities. Samples (n = 38) from 8 dairy, 2 calf, and 3 swine facilities in California were collected over a 3-yr period and characterized for their dielectric properties, chemical composition, and suitability for thermal processing using RF power. To establish efficacy for disinfection, selected samples were inoculated with high levels (10(6) to 10(9) cfu/mL) of bacterial pathogens such as Salmonella sp., Escherichia coli O157:H7, and Mycobacterium avium ssp. paratuberculosis and processed with an RF prototype system. The capabilities of RF power as a method for thermal disinfection of wastewater were demonstrated when bacteria pathogens were completely and rapidly (<1 min) inactivated when temperatures of 60 to 65 degrees C were achieved. Furthermore, RF technology can be used for large-scale, batch or continuous and portable applications, allowing significant improvements in energy-use efficiencies compared with conventional thermal (surface heating) technologies. Therefore, RF power has potential as an alternative to disinfect dairy/animal farm wastewater before recycling.