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High levels of genetic variation in the haploid leafy liverwort Porella platyphylla from the southeastern United States

The few studies that have investigated levels of genetic variation in liverworts have found very little polymorphism. Our electrophoretic data show, however, that the leafy liverwort Porella platyphylla maintains high levels of genetic variation in at least some natural populations from the southeastern United States. Within a single population from southwestern North Carolina, we detected 26 dist

Determinants of woody cover in African savannas

Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties(1-3). The availability of resources ( water, nutrients) and disturbance regimes ( fire, herbivory) are thought to be important in regulating woody cover(1,2,4,5), but percep

The long-term stability of temperament traits measured after a suicide attempt. A 5-year follow-up of ratings of Karolinska Scales of Personality (KSP)

The main aim of the present study was to investigate whether or not temperament dimensions are stable over time. Twenty-six patients (21 women and five men) filled in the Karolinska Scales of Personality (KSP) both at admission after a suicide attempt (index) and at follow-up 5 years later. KSP changes were significantly associated with low severity of psychiatric symptoms and no reported reattemp

Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system

An airfreight container with automated instruments for measurement of atmospheric gases and trace compounds was operated on a monthly basis onboard a Boeing 767-300 ER of LTU International Airways during long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container, http://www.caribic-atmospheric.com). Subsequently a m

Water uptake and release from iodine-containing bone cement.

Water uptake and release characteristics of PMMA cement containing the water-soluble contrast media iohexol or iodixanol have been investigated. The water uptake study revealed that iohexol had the highest uptake of water (3.7%) and that iodixanol had an uptake close to that of Palacos(R) R (2.3% and 1.9%). The curves obtained showed the materials to follow classic diffusion theory, with an initia

Galileo dust data from the jovian system: 1997-1999

The dust detector system on board the Galileo spacecraft recorded dust impacts in circumjovian space during the craft's orbital mission about Jupiter. This is the eighth in a series of papers dedicated to presenting Galileo and Ulysses dust data. We present data from the Galileo dust instrument for the period January 1997-December 1999 when the spacecraft completed 21 revolutions about Jupiter. In

Determination of short-chain fatty acids in serum by hollow fiber supported liquid membrane extraction coupled with gas chromatography

A method based on hollow fiber supported liquid membrane extraction coupled with a gas chromatograph equipped with flame ionization detector (GC-FID) was developed for the determination of six short-chain fatty acids including acetic acid, propionic acid, i-butyric acid, n-butyric acid, i-valeric acid and n-valeric acid in serum. Hollow fiber supported liquid membrane extraction was employed for p

The influence of surgical trauma on factor XaI and IIaI activity and heparin concentration after a single dose of low-molecular-weight heparin

To study the influence of surgical trauma on the XaI and IIaI activity after injection of a low-molecular-weight heparin (LMWH) 24 patients undergoing elective cholecystectomy received one subcutaneous injection of the LMWH Fragmin. Each group of eight patients received either 2,500 or 5,000 XaI U 2 h before operation or 5,000 XaI U 10 h before surgery. For comparison an additional eight patients

A morphometrical comparison of right and left whole human vastus lateralis muscle: how to reduce sampling errors in biopsy techniques

In studies of the effects of different training programmes, one muscle--most commonly the vastus lateralis--is used for the experiment while the contralateral muscle serves as a control, at the same time as muscle biopsies are taken from both sides. In order to increase the reliability of such studies, the sources and the magnitude of the sampling errors in the biopsy techniques need to be assesse

Regulation of protein kinase B in rat adipocytes by insulin, vanadate, and peroxovanadate. Membrane translocation in response to peroxovanadate

Protein kinase B (PKB) (also referred to as RAC/Akt kinase) has been shown to be controlled by various growth factors, including insulin, using cell lines and transfected cells. However, information is so far scarce regarding its regulation in primary insulin-responsive cells. We have therefore used isolated rat adipocytes to examine the mechanisms, including membrane translocation, whereby insuli

Direct heterogeneous electron transfer reactions of bilirubin oxidase at a spectrographic graphite electrode

Mediatorless (direct) electron transfer between Myrothecium verrucaria bilirubin oxidase and spectroscopic graphite electrode has been demonstrated. The electrochemical activity of the enzyme under aerobic and anaerobic conditions is clearly shown using cyclic voltammetry. It is concluded that the T1 site of the enzyme is the first electron acceptor, both in solution (homogenous case) and when the

Comparing atmospheric transport models for future regional inversions over Europe : part 1 : mapping the atmospheric CO2 signals

The CO2 source and sink distribution across Europe can be estimated in principle through inverse methods by combining CO2 observations and atmospheric transport models. Uncertainties of such estimates are mainly due to insufficient spatiotemporal coverage of CO2 observations and biases of the models. In order to assess the biases related to the use of different models the CO2 concentration field o

Impact of an 84-hour workweek on biomarkers for stress, metabolic processes and diurnal rhythm

Objectives This study examined the degree to which long workhours in combination with an extended workweek (12 hours/7 days) with permanent day shifts (0700-1900), as requested by the workers, influenced biomarkers for stress, metabolic processes, and diurnal rhythm. Methods Construction workers (N=50) working 84 hours a week, with alternate weeks off, were compared with construction workers (N=25

An open randomised trial of second-line endocrine therapy in advanced breast cancer: comparison of the aromatase inhibitors letrozole and anastrozole

It was previously shown that letrozole (Femara(R)) was significantly more potent than anastrozole (Arimidex(R)) in inhibiting aromatase activity in vitro and in inhibiting total body aromatisation in patients with breast cancer. The objective of this study was to compare letrozole (2.5 mg per day) and anastrozole (1 mg per day) as endocrine therapy in postmenopausal women with advanced breast canc

Enzyme conformational alterations detected by partition column chromatography

In this paper, we demonstrate the ability of liquid-liquid partition chromatography (LLPC) to detect conformational alterations occurring in well-characterized enzymes. The conformational changes induced in dehydrogenases such as alcohol dehydrogenase (ADH), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), lactate dehydrogenases (LDH) and malate dehydrogenase (MDH) upon binding of ligand(s) were

Association interaction and voltammetric determination of 1-aminopyrene and 1-hydroxypyrene at cyclodextrin and DNA based electrochemical sensors

The aim of this work was voltammetric determination of 1-aminopyrene and 1-hydroxypyrene using carbon paste electrodes modified with cyclodextrin derivatives and double stranded deoxyribonucleic acid (dsDNA). The detection schemes based on a preconcentration and differential pulse voltammetric (DPV) determination at beta-cyclodextrin and gamma-cyclodextrin modified carbon paste electrode (beta-CD/

Fresh frozen plasma reduces thrombin formation in newborn infants

BACKGROUND: Newborn infants undergoing intensive care are at risk of bleeding and thrombotic complications. Fresh frozen plasma (FFP) is used in hope of preventing these complications, despite poorly defined effects on the coagulation system and lack of proven clinical efficacy. OBJECTIVES AND METHODS: We prospectively evaluated coagulopathy and the effect of standardized amount of FFP transfusion