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Multiple paternity in reptiles: patterns and processes

The evolution of female promiscuity poses an intriguing problem as benefits of mating with multiple males often have to arise via indirect, genetic, effects. Studies on birds have documented that multiple paternity is common in natural populations but strong evidence for selection via female benefits is lacking. In an attempt to evaluate the evidence more broadly, we review studies of multiple pat

Temporary increase of FSH levels in healthy, nulliparous, young women after cessation of low-dose oral contraceptive use

PIP: At the University Hospital in Lund, Sweden, researchers grouped healthy nulliparous women aged 19-25 into current, former, and never users of low-dose combined oral contraceptives (OCs) to examine the effect of the OCs on the levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH). The subjects were from two independent samples. Based on the day the blood was sampled, their

Management of patients with polycythaemia vera: results of a survey among Swedish haematologists

The prevailing attitudes regarding diagnostic and therapeutic procedures in patients with polycythaemia vera (PV) among Swedish haematologists were surveyed by way of a mailed questionnaire in August 2002. Among diagnostic procedures frequent use is reported for arterial O-2 saturation, spleen size determination, bone marrow histology, serum erythropoietin, serum cobalamins and leukocyte alkaline

A piecewise hyperbolic map with absolutely continuous invariant measure

We consider a class of non-invertible piecewise affine hyperbolic endomorphisms with singularities and show that for an open set of parameters there exists almost surely an absolutely continuous invariant measure. Also, exponential decay of correlations is proved for Holder continuous functions.

Genetic isolation and divergence in sexual traits: evidence for the northern rockhopper penguin Eudyptes moseleyi being a sibling species

The taxonomic status of populations of rockhopper penguins (Eudyptes chrysocome) is still enigmatic. Northern populations differ from southern ones in breeding phenology, song characteristics and head ornaments used as mating signals. We conducted a molecular analysis using mitochondrial DNA sequencing to test if there is a gene flow barrier between northern (subtropical) populations and southern

Height-controlled nanowire branches on nanotrees using a polymer mask

The production of complex three-dimensional dendritic structures is an important step in the application of semiconductor nanowires. One promising method for achieving this is the sequential seeding of multiple generations of epitaxial nanowires using metal seed particles. However, it is difficult to control and predict the position of second and higher generation nanowires with respect to the fir

Aggressive treatment of acute limb ischemia due to thrombosed popliteal aneurysms

OBJECTIVE: The absence of infra-popliteal runoff in patients with acute limb ischemia and thrombosed popliteal aneurysms carries a high risk of amputation. A combined treatment method involving thrombolysis and surgery is reported. MATERIAL AND METHODS: Information regarding six patients was reviewed. Ankle brachial indices and degree of ischemia were recorded. All patients underwent digital subtr

Lines of O IV and S IV in the Goddard High-Resolution Spectrograph spectrum of RR Tel: constraints on atomic data

High signal-to-noise ratio spectra of RR Tel obtained at medium resolution with the Goddard High-Resolution Spectrograph (GHRS) on the Hubble Space Telescope (HST) are used to test available atomic data for the O IV 2s(2)2p P-2-2s2p(2) P-4 multiplet (UV 0.01). The fine-structure intervals of the 2s2p(2) P-4 term given by Moore (1983) appear to need revision. The flux ratios of lines within multipl

Quantitative assessment of swallowing in healthy adults

Swallowing has hitherto been evaluated during physical examination, radiologic barium studies, manometry, and cervical auscultation. Radiography principally demonstrates qualitative aspects of oral and pharyngeal function, whereas quantitative aspects have primarily been documented by manometry. To evaluate swallowing quantitatively, without using invasive methods or radiation, we have applied a c

Isolation and characterization of galactoglucomannan from spruce (Picea abies)

Water-soluble hemicelluloses were extracted from spruce chips by microwave heat fractionation. The chips were impregnated with water at different pH values. Screening of heat-fractionation conditions, i.e. impregnation medium, temperature and residence time was performed with the aim to extract O-acetyl-galactoglucomannan. The impregnation and heat fractionation conditions were evaluated on the ba

Time course of cerebellar morphological development in postnatal ferrets: Ontogenetic and comparative perspectives.

We provide the first systematic description of the morphological ontogenesis of the ferret cerebellum and compare its relative time-course to that of the rat cerebellum. Overall cerebellar size, foliation, and thickness of cortical layers were quantified and Purkinje cell morphology was characterized at 24 timepoints in ferrets from postnatal day (P)1 to P63. The ferret cerebellum was substantiall

Biosorption of chromium (III) and chromium (VI) by untreated and pretreated Cassia fistula biomass from aqueous solutions

The present study explained the effect of pretreatments on the biosorption of Cr (III) and Cr (VI) by Cassia fistula biomass from aqueous solutions. For this purpose Cassia fistula biomass was pretreated physically by heating, autoclaving, boiling and chemically with sodium hydroxide, formaldehyde, gluteraldehyde, acetic acid, hydrogen peroxide, commercial laundry detergent, orthophosphoric, sulph

Group I intron versus ITS sequences in phylogeny of cetrarioid lichens.

Phylogenetic trees based on group I intron sequences and on internal transcribed spacer (ITS) sequences of mycobiont ribosomal genes were calculated and compared. Eight cetrarioid and four non-cetrarioid species of the Parmeliaceae were compared. The phylogeny based on group I intron sequences is partly congruent with the ITS sequence phylogeny. Group I intron sequences are presumably less informa

Appropriate assessment of neighborhood effects on individual health: Integrating random and fixed effects in multilevel logistic regression

The logistic regression model is frequently used in epidemiologic studies, yielding odds ratio or relative risk interpretations. Inspired by the theory of linear normal models, the logistic regression model has been extended to allow for correlated responses by introducing random effects. However, the model does not inherit the interpretational features of the normal model. In this paper, the auth

Early Holocene history of the Baltic Sea, as reflected in coastal sediments in Blekinge, southeastern Sweden

Integrated palaeoecological studies of two fiord sediment sequences in the province of Blekinge, SE Sweden, covering the time span 11,000-5000 cal BP, reveal the timing and the environment for the Ancylus Lake/Littorina Sea transition 9800-8500 cal BP. The first ingression of saline water into the Baltic Sea through the Danish Straits occurred earlier than formerly assumed. New evidence, particula

Formation of a liquid crystalline phase from phosphatidylcholine at the oil-aqueous interface

Adsorption of phospholipid (1,2-dioleoyl-sn-glycero-3-phosphatidylcholine) and formation of a surface phase at the oil-water interface has been followed by using ellipsometry. The properties of the interfacial phase were found to depend strongly on whether phospholipid was added to the oil phase or to the aqueous phase as liposomal structures. In the latter case a monolayer formed, while if the ph