Surveying colloid sedimentation by coplanar waveguides.

By using coplanar waveguides, direct access to the dielectric properties of aqueous solutions of polystyrene beads with different diameters from 330 nm to 10 µm is provided. The relative variation of the transmission parameter with respect to water is monitored, ranging from [Formula: see text] obtained for a 9.5% solution with 330 nm diameter beads to ∼22% for 10 µm diameter particles at the same concentration. To highlight its applicability in biosensing, the technique was further employed to survey the clustering between biotin and streptavidin-coated beads. The transmission parameter displays a ∼50% increase for mixtures containing nine volumes of biotin and one volume of streptavidin-modified beads (4.5 ng µl(-1) of streptavidin) and reaches ∼400% higher values when equal volumes of biotin and streptavidin-coated beads (22.5 ng µl(-1) of streptavidin) were mixed.

[New approaches to prenatal diagnosis of rhesus incompatibility]. / Nouvelles stratégies dans la prise en charge de l'allo-immunisation foeto-maternelle anti-RHD (Rhésus).

Despite generalisation of anti-D immunoprophylaxis, RhD allo-immunisation still remains the major cause of severe haemolytic disease of the fetus and of the newborn (HDFN). The routine follow up of pregnant women comprises: the ABO/D, Rh/Kell red cells typing and the search for irregular antibodies. In case of anti-D immunisation, the paternal Rh phenotype, when known, provides useful information regarding the probability for the fetus to have inherited the D antigen and thereby to be exposed to the risk of HDFN. The antibody titre, which is predictive of possible in vivo haemolysis, must be interpreted in the light of the previous obstetric history, and can lead to the decision of invasive amniocentesis. Then the measurement of the optical density (deltaOD450 nm) and the fetal RhD typing can be realised on amniotic fluid. New molecular techniques make it possible now to demonstrate the presence of fetal DNA in maternal plasma. These methods lying on non invasive procedures could advantageously be applied to the genotyping of fetal RHD during pregnancy. The present paper aims to discuss the predictive values of RHD fetal genotype in maternal plasma of RhD negative mothers. The ante-partum management of immunised pregnant women is reviewed in the light of this new molecular approach combined to Doppler ultrasonography of the fetal middle cerebral artery. This non invasive method for determining fetal RHD genotype could be systematically proposed to all RhD negative pregnant women for a better targeted prenatal follow-up and an increased efficacy of RhD prophylaxis.

Current management of facial wounds in UK accident and emergency departments.

INTRODUCTION: The objective of this study was to determine the current practice in the management of adult facial soft tissue injuries in patients presenting to UK accident and emergency departments. MATERIALS AND METHODS: Questionnaire study to the lead clinicians of 217 UK emergency departments seeing over 30,000 new patients annually. RESULTS: There was a 76% response rate. Suturing was the preferred method of closure, with the majority of clinicians preferring 6/0 or 5/0 non-resorbable sutures. Use of a regional nerve block would be considered by a quarter of clinicians, and adrenaline vasoconstrictor by a third. Referral rates ranged from 5-77% for a more complex wound. Maxillofacial services were preferred by 51% of respondents; on-site referral availability was indicated by only 28%, with an average journey of 16 miles for treatment. Up to 30% of clinicians considered prescribing antibiotics after wound closure, with flucloxacillin and co-amoxiclav most commonly suggested. Accident and emergency review rates ranged from 16% to 45%, with most wounds either being referred to the GP or no formal review being suggested. CONCLUSIONS: The results of this survey suggest that there is considerable variation in the initial management, referral and review of facial wounds in the UK. Further work is required to formulate guidelines for optimal patient care, ideally in conjuncture with the receiving surgical specialties.

A normal' category-specific advantage for naming living things.

'Artefactual' accounts of category-specific disorders for living things have highlighted that compared to nonliving things, living things have lower name frequency, lower concept familiarity and greater visual complexity and greater within-category structural similarity or 'visual crowding' [7]. These hypotheses imply that deficits for living things are an exaggeration of some 'normal tendency'. Contrary to these notions, we found that normal subjects were consistently worse at naming nonliving than living things in a speeded presentation paradigm. Moreover, their naming was not predicted by concept familiarity, name frequency or visual complexity; however, a novel measure of visual familiarity (i.e. for the appearance of things) did significantly predict naming. We propose that under speeded conditions, normal subjects find nonliving things harder to name because their representations are less visually predictable than for living things (i.e. nonliving things show greater within-item structural variability). Finally, because nonliving things have multiple representations in the real world, this may lower the probability of finding impaired naming and recognition in this category.