Are 10 min of seating enough to guarantee stable haemoglobin and haematocrit readings for the athlete's biological passport?

Haemoglobin (Hb) and haematocrit (Hct) are measured as indirect markers of doping in athletes. We studied the effect of posture on these parameters in a typical antidoping setting. Venous blood samples were obtained from nine endurance athletes (six males, three females) and nine control subjects (six males, three females) immediately and after 5, 10, 15, 20 and 30 min after having adopted a seated position from normal daily activity. Hb (CV 0.72%) and Hct (CV 0.87%) were determined using an automated cell counter, plasma volume changes were calculated. Differences between the time points, gender and groups were calculated using a mixed-model procedure. Significant changes were observed in the first 10 min after sitting down but no further changes were noted between 10 and 30 min. Mean directional change for Hb and Hct between 0 min and the average of the period from 10 to 30 min was -2.4% (-0.35 g/dl) for Hb and -2.7% (-1.2%) for Hct. Plasma volume increased accordingly. Neither group nor gender had significant effects. Under typical conditions encountered during blood testing in doping control, a period of 10 min in a seated position is sufficient for the vascular volumes to re-equilibrate and to adapt to the new posture.

Mineralogical, K-Ar, stable and Sr isotope systematics of K-white micas during very low-grade metamorphism of limestones (Helvetic nappes, Western Switzerland)

Mineralogical, K-Ar, Rb-Sr and stable isotope analyses have been carried out on K-white micas from Helvetic Malm limestones in order to examine their evolution during very low- to low-grade Alpine metamorphism, associated with intense ductile deformation. Metamorphic temperatures were estimated al approximately 300-degrees-C from stable isotopes (quartz-calcite thermometry), occurrence of chloritoid, and `'epizonal'' illite crystallinity index. K-white micas consist of variable mixtures of 2M, phengite and muscovite, as revealed by detailed X-ray diffraction analyses using peak decomposition of the (060, 331) spectra. K-Ar apparent ages display a strong grain-size dependence in which mainly fine-grained size fractions (< 2 mum) record Alpine ages (37-15 Ma). However, these ages provide a relative rather than an absolute chronology of the diachronous Alpine metamorphic evolution of the Helvetic nappes. The resetting of the K-Ar isotopic system of K-white micas to Alpine metamorphic conditions reflects an apparent combination of crystallization/recrystallization and radiogenic Ar-40 diffusion loss. The oxygen isotope compositions of micas (+ 15 to + 22 parts per thousand) are intermediate between detrital and O-18-enriched values expected for micas neoformed within an abundant marine carbonate matrix. No isotopic equilibrium has been reached between calcite and micas. The variable depletion of hydrogen isotope compositions (- 126 to - 82 parts per thousand) is influenced by the interaction with organic matter under closed-system conditions. Organic matter, if not removed, may also represent a serious source of error in K-Ar age determination, by introducing radiogenic Ar-40 contamination. Sr-87/Sr-86 isotope ratios of micas range from 0.70879 to 0.70902 with one outlier at 0.71794. The low values reflect Sr exchange with calcite occurring during crystallization/recrystallization of micas under closed-system conditions.

Transformation kernel density estimation of actuarial loss functions

[cat] Es presenta un estimador nucli transformat que és adequat per a distribucions de cua pesada. Utilitzant una transformació basada en la distribució de probabilitat Beta l’elecció del paràmetre de finestra és molt directa. Es presenta una aplicació a dades d’assegurances i es mostra com calcular el Valor en Risc.

Suboptimal filtering and nonlinear time scale transformation for the analysis of multiexponential decays

Multiexponential decays may contain time-constants differing in several orders of magnitudes. In such cases, uniform sampling results in very long records featuring a high degree of oversampling at the final part of the transient. Here, we analyze a nonlinear time scale transformation to reduce the total number of samples with minimum signal distortion, achieving an important reduction of the computational cost of subsequent analyses. We propose a time-varying filter whose length is optimized for minimum mean square error

Stable one-step technetium-99m labeling of His-tagged recombinant proteins with a novel Tc(I)-carbonyl complex.

We have developed a technetium labeling technology based on a new organometallic chemistry, which involves simple mixing of the novel reagent, a 99m Tc(I)-carbonyl compound, with a His-tagged recombinant protein. This method obviates the labeling of unpaired engineered cysteines, which frequently create problems in large-scale expression and storage of disulfide-containing proteins. In this study, we labeled antibody single-chain Fv fragments to high specific activities (90 mCi/mg), and the label was very stable to serum and all other challenges tested. The pharmacokinetic characteristics were indistinguishable from iodinated scFv fragments, and thus scFV fragments labeled by the new method will be suitable for biodistribution studies. This novel labeling method should be applicable not only to diagnostic imaging with 99mTc, but also to radioimmunotherapy approaches with 186/188 Re, and its use can be easily extended to almost any recombinant protein or synthetic peptide.

Aggregate monotonic stable single-valued solutions for cooperative games

[cat] En aquest treball caracteritzem les solucions puntuals de jocs cooperatius d'utilitat transferible que compleixen selecció del core i monotonia agregada. També mostrem que aquestes dues propietats són compatibles amb la individualitat racional, la propietat del jugador fals i la propietat de simetria. Finalment, caracteritzem les solucions puntuals que compleixen les cinc propietats a l'hora.

Transformation kernel density estimation of actuarial loss functions

[cat] Es presenta un estimador nucli transformat que és adequat per a distribucions de cua pesada. Utilitzant una transformació basada en la distribució de probabilitat Beta l’elecció del paràmetre de finestra és molt directa. Es presenta una aplicació a dades d’assegurances i es mostra com calcular el Valor en Risc.

Labile and stable fractions of soil organic matter under management systems and native cerrado

Soil organic matter can be analyzed on the basis of the different fractions. Changes in the levels of organic matter, caused by land use, can be better understood by alterations in the different compartments. The aim of this study was to evaluate the effect of different management systems on the labile and stable organic matter of a dystrophic Red Latosol (Oxisol). The following properties were determined: total organic C and total N (TOC and TN), particulate organic C and particulate N (POC and PN), organic C and N mineral-associated (MOC and NM) and particulate organic C associated with aggregate classes (POCA). Eight treatments were used: seven with soil management systems and one with native Cerrado as a reference. The experiment was designed to study the dynamics of systems of tillage and crop rotation, alternating in time and space. The experimental design was a randomized block design with three replications. The soil samples were collected from five depths: 0-5, 5-10, 10-20, 20-30 and 30-40 cm. Changes in organic C by land use occurred mainly in the fraction of particulate organic matter (> 53 mm). Proper management of grazing promoted increased levels of particulate organic matter by association with larger aggregates (2-8 mm), demonstrating the importance of the formation of this aggregate class for C protection in pasture.

The daily energy expenditure in stable chronic obstructive pulmonary disease.

Resting energy expenditure is frequently increased in chronic obstructive pulmonary disease (COPD), but it is unknown if this hypermetabolism holds true over 24 h. The aim of this study was to measure the actual 24-h energy expenditure (24-h EE) in patients with stable COPD. Energy expenditure was measured by indirect calorimetry, using a metabolic chamber for 24-h EE and a canopy for basal metabolic rate (BMR). Physical activity was detected in the chamber by a radar system, and its duration was quantified. Two groups matched for age and height were studied: 16 male ambulatory patients with stable COPD and 12 male normal subjects. Body weight was 92 +/- 12% of ideal body weight in the group with COPD and 108 +/- 11% in the control group (p = 0.01). BMR was 120 +/- 7% of predicted in the group with COPD and 108 +/- 12% in the control group (p < 0.01). However, 24-h EE was similar in the two groups, amounting to 1,935 +/- 259 kcal in patients with COPD and 2,046 +/- 253 kcal in the control group (NS). This corresponded to 145% and 137% of predicted BMR, and to 121% and 126% of measured BMR in patients with COPD and the control group, respectively (NS). Patients were allowed to pursue their usual treatment within the chamber, and a positive correlation existed between 24-h EE and the daily dose of inhaled beta 2-agonists (p < 0.03). During daytime, physical activity was lower in patients with COPD. This study shows that patients with stable COPD are characterized by a normal daily energy expenditure in controlled conditions in spite of an increased basal metabolic rate. They appear to save energy by reducing their spontaneous level of physical activity.

Post-transcriptional down-regulation of expression of transcription factor NF1 by Ha-ras oncogene.

NF1 is a family of polypeptides that binds to discrete DNA motifs and plays varying roles in the regulation of gene expression. These polypeptides are also thought to mediate the expression of differentiation-specific markers such as adipocyte and mammary cell type-specific genes. The expression of a number of cellular differentiation-specific markers is down-regulated during neoplastic transformation. We therefore investigated whether oncogenic transformation interferes with the action of NF1. Stable transfection of activated Ha-ras into a number of murine cells correlated with a down-regulation of the expression of the NF1 genes NF1/CTF and NF1/X. The down-regulation was not at the transcriptional level but at the level of stability of the NF1 mRNAs. The level of the DNA binding activity of the NF1 proteins was also reduced in Ha-v-ras-transformed cells, and the expression of a gene that depends on this family of transcription factors was specifically repressed. These results demonstrate that an activated Ha-ras-induced pathway destabilizes the half-life of mRNAs encoding specific members in the NF1 family of transcription factors, which leads to a decrease in NF1-dependent gene expression.