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A simple test device for electrometers

Electrometers used in dosimetric instruments need to be checked regularly in order to measure and maintain the prescribed dose to the patient. This paper describes the function of a simple but accurate test device for electrometers. A number of electrometers have been tested and compared with calibrations performed by the Swedish Standard Dosimetry Laboratory (SSDL). The device can be used to test

The history of echocardiography

Following a brief review of the development of medical ultrasonics from the mid-1930s to the mid-1950s, the collaboration between Edler and Hertz that began in Lund in 1953 is described. Using an industrial ultrasonic flaw detector, they obtained time-varying echoes transcutaneously from within the heart. The first clinical applications of M-mode echocardiography were concerned with the assessment

The Danish Prostatic Symptom Score (DAN-PSS-1) questionnaire is reliable in stroke patients

Aims: To investigate the test-retest reliability of Danish Prostatic Symptom Score (DAN-PSS-1) questionnaire in a sample of stroke patients. Methods: A prospective study design was used in which the stroke patients were invited to complete a postal self-administrated DAN-PSS-1 questionnaire twice. The questionnaire consists of 12 questions related to lower urinary tract symptoms (LUTS). The partic

Irinotecan plus carboplatin versus oral etoposide plus carboplatin in extensive small-cell lung cancer: A Randomized phase III trial

Purpose A Japanese randomized trial showed superior survival for patients with extensive-disease (ED) small-cell lung cancer (SCLC) receiving irinotecan plus cisplatin compared with etoposide plus cisplatin. The present trial evaluated the efficacy of irinotecan plus carboplatin (IC) compared with oral etoposide plus carboplatin (EC). Patients and Methods Patients with ED SCLC were randomly assign

Exposure to polybrominated diphenyl ethers and tetrabromobisphenol A among computer technicians.

This study investigates exposure to polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), which are used as flame retardants in electronic equipment, in a group of technicians with intense computer work. Thirteen PBDE congeners and TBBPA were quantified in serum from 19 computer technicians. Previously investigated groups of hospital cleaners with no computer experience, and cl

Pilot-scale extraction of an intracellular recombinant cutinase from E. coli cell homogenate using a thermoseparating aqueous two-phase system

A thermoseparating aqueous two-phase system for extraction of a recombinant cutinase fusion protein from Escherichia coli homogenate has been scaled up to pilot scale. The target protein ZZ-cutinase-(WP)4 was produced in a fed batch process at 500 l to a concentration of 12% of the total protein and at a cell concentration of 19.7 g l-1. After harvest and high-pressure homogenisation a first extra

Effect of polyamine deficiency on proteins involved in Okazaki fragment maturation.

Polyamine depletion causes S phase prolongation, and earlier studies indicate that the elongation step of DNA replication is affected. This led us to investigate the effects of polyamine depletion on enzymes crucial for Okazaki fragment maturation in the two breast cancer cell lines MCF-7 and L56Br-C1. In MCF-7 cells, treatment with N(1),N(11)-diethylnorspermine (DENSPM) causes S phase prolongatio

Manifestation of anharmonic resonance in the interaction of intense ultrashort laser pulses with microstructured targets

Identification of the basic processes responsible for an efficient heating of intense laser produced plasmas is one of the important features of high intensity laser matter interaction studies. Collisionless absorption due to the anharmonicity in the self-consistent electrostatic potential of the plasma, known as anharmonic resonance (AHR), has been proposed to be a basic mechanism but a clear exp

Evolution of nucleotide sequences and expression patterns of hydrophobin genes in the ectomycorrhizal fungus Paxillus involutus

Hydrophobins are small, secreted proteins that play important roles in the development of pathogenic and symbiotic fungi. Evolutionary mechanisms generating sequence and expression divergence among members in hydrophobin gene families are largely unknown. Seven hydrophobin (hyd) genes and one hyd pseudogene were isolated from strains of the ectomycorrhizal fungus Paxillus involutus. Sequences wer

Strengthening the case for stimulus-specificity in artificial grammar learning: No evidence for abstract representations with extended exposure

Different theories have been proposed regarding the nature of the mental representations formed as a result of implicit learning of sequential regularities. Some theories postulate abstract surface-independent representations, while other theories postulate stimulus-specific representations. This article reports three experiments investigating the development of abstract representations in artific

Adaptive variation of airspeed in relation to wind, altitude and climb rate by migrating birds in the Arctic

The power expenditure of flapping flight in birds is characterised by a U-shaped function of speed through the air. From this relationship and the assumption of limited power available from flight muscles, it is possible to predict changes in the birds' airspeed in relation to external factors such as wind. These predictions are derived from flight mechanical theory and optimality criteria concern

Induction of platelet thrombi by bacteria and antibodies

We have characterized 2 distinct mechanisms through which infectious agents may promote platelet adhesion and thrombus formation in flowing blood, thus contributing to the progression of disease. In one case, the process initiates when the integrin alpha(IIb)beta(3) mediates platelet arrest onto immobilized bacterial constituents that have bound plasma fibrinogen. If blood contains antibodies agai

Topography of vision and behaviour

Given the great range of visual systems, tasks and habitats, there is surprisingly little experimental evidence of how visual limitations affect behavioural strategies under natural conditions. Analysing this relationship will require an experimental system that allows for the synchronous measurement of visual cues and visually guided behaviour. The first step in quantifying visual cues from an an

Evidence for Two Mg Related Acceptors in GaN

The optical signatures of Mg-related acceptors in GaN have been revisited in samples specifically grown on bulk GaN templates, to avoid strain broadening of the optical spectra. Bound-exciton spectra can be studied in these samples for Mg concentrations up to [Mg]approximate to 2x10(19) cm(-3). Contrary to previous work it is found that instabilities in the photoluminescence spectra are not due to

Coordinated patterns of cytochrome bd and lactate dehydrogenase expression in Bacillus subtilis

A variety of pathways for electron and carbon flow in the soil bacterium Bacillus subtilis are differentially expressed depending on whether oxygen is present in the cell environment. This study characterizes the regulation of the respiratory oxidase cytochrome bd and the NADH-linked fermentative lactate dehydrogenase, (LDH). Transcription of the cydABCD operon, encoding cytochrome bd, is highly r

Computer program (shock) to predict acid shocks in watersheds using stochastic analysis

High hydrogen ion concentrations of runoff events were analyzed in terms of the probability distributions of frequency, duration, magnitude, and time of occurrence. Simple stochastic models were applied to the probability distributions of the annual frequency of high hydrogen ion concentration flows and their magnitudes. A consideration of the statistical properties of the given stochastic variabl