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A ROLE FOR LEARNING IN POPULATION DIVERGENCE OF MATE PREFERENCES.

ABSTRACT Learning and other forms of phenotypic plasticity have been suggested to enhance population divergence. Mate preferences can develop by learning, and species recognition might not be entirely genetic. We present data on female mate preferences of the banded demoiselle (Calopteryx splendens) that suggest a role for learning in population divergence and species recognition. Populations of t

Vegetation history and lake-level changes from the Younger Dryas to the present in Eastern Pyrenees (France): pollen, plant macrofossils and lithostratigraphy from Lake Racou (2000 m a.s.l.)

A multi-proxy palaeoecological investigation including pollen, plant macrofossil, radiocarbon and sedimentological analyses, was performed on a small mountain lake in the Eastern Pyrenees. This has allowed the reconstruction of: ( 1) the vegetation history of the area based on five pollen diagrams and eight AMS(14)C dates and ( 2) the past lake-level changes, based on plant macrofossil, lithologic

Stochastic Modeling and Operational Optimization in District Heating Systems

Operation of a district heating system is accomplished via a sequence of decisions by the operators controlling the system. These decisions are based on expectations of conditions in the system that are not known at decision time. The operators could be helped by a decision support system that computes predictions of future system variables and suggests appropriate control actions given the availa

One-year low-dose erythromycin treatment of persistent chronic sinusitis after sinus surgery: clinical outcome and effects on mucociliary parameters and nasal nitric oxide.

OBJECTIVE: In 17 patients with chronic sinusitis persistent after sinus surgery, long-term, low-dose erythromycin therapy was tested. The aim of the investigation was to study the clinical outcome and effects on nasal nitric oxide (NO), ciliary beat frequency (CBF), and mucociliary transport (saccharine transit time). STUDY DESIGN AND SETTING: We conducted a prospective open study at a tertiary te

Tobacco smoking increases dramatically air concentrations of endotoxin.

We used a mass spectrometry-based assay for identifying the endotoxin (lipopolysaccharide, LPS) marker (R)-3-hydroxytetradecanoic acid in cigarette smoke particles and found that smoking involved inhalation of 17.4 pmol of endotoxin per each smoked cigarette. Indoor exposure to environmental tobacco smoke (ETS) entailed inhalation of 12.1 pmol of LPS/m3 air, an amount that was 120 times higher tha

Integration between abutting retinas: Role of glial structures and associated molecules at the interface

PURPOSE. Integration between subretinal grafts and the host retina is limited in part by the presence of a barrier at the graft-host interface. This study was conducted to identify factors that may contribute to this barrier, by examining the distribution of glial structures and associated molecules in different setups of overlapping retinal pieces. METHODS. Neuroretinal tissue derived from mice t

Miljömålet i skogsbruket : Styrning och frivillighet

Popular Abstract in Swedish Införandet av 1993 års skogspolitiska beslut med ett jämställt miljö- och produktionsmål, belyser den historiskt befästa konflikten mellan allmänintresse och egenintresse: statens vilja och behov att styra produktion och avkastning kontra den enskilde skogsägarens rätt att själv bestämma över sin skog. Idag har denna konflikt styrt över mot en statligt uttalad målsättniThis dissertation analyzes the changes in the way Swedish forest policy has been developed and implemented in the past few decades. Its primary focus is on the period from the adoption of new legislation governing forestry in 1993 to date, though the historical antecedents of the more recent developments are also discussed. The dissertation focuses primarily on the interplay between changes in the

Enterolactone is differently associated with estrogen receptor beta-negative and -positive breast cancer in a Swedish nested case-control study

BACKGROUND: Differences in the estrogen receptor (ER) status of tumors may explain ambiguities in epidemiologic studies between the blood concentrations of enterolactone and breast cancer. To our knowledge, the association between enterolactone and ERbeta-defined breast cancer has previously not been examined.METHODS: A nested case-control study within the Malmö Diet and Cancer cohort used 366 cas

Frequent CXCR4 tropism of HIV-1 subtype A and CRF02_AG during late-stage disease - indication of an evolving epidemic in West Africa

Background: HIV-1 is one of the fastest evolving pathogens, and is distinguished by geographic and genetic variants that have been classified into different subtypes and circulating recombinant forms (CRFs). Early in infection the primary coreceptor is CCR5, but during disease course CXCR4-using HIV-1 populations may emerge. This has been correlated with accelerated disease progression in HIV-1 su

Ability and rates of return to schooling-making use of the Swedish enlistment battery test

Using the Swedish military enlistment test, this paper estimates the return to schooling for individuals belonging to different parts of the ability distribution. It also attempts to predict whether an endogenous test score causes bias in the "ability-specific" returns to schooling that varies with the test score. A significant finding is that a higher score in the test is associated with a higher

Meta-analysis identifies 13 new loci associated with waist-hip ratio and reveals sexual dimorphism in the genetic basis of fat distribution

Waist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association studies for WHR adjusted for body mass index (comprising up to 77,167 participants), following up 16 loci in an addit

A calibration system for soil carbon dioxide efflux measurement chambers: Description and application

Comparisons have revealed large discrepancies among the many methods for measuring soil CO2 efflux indicating the need for an absolute calibration of methods. This study presents a calibration system, constructed to imitate an area of soil, and its application to two different chamber systems for the measurement Of Soil CO2 efflux: one open and one closed dynamic. Air rich in CO2 was allowed to di

Approximate time-variable coherence analysis of multichannel signals

We present a new method for signal extraction from noisy multichannel epileptic seizure onset EEG signals. These signals are non-stationary which makes time-invariant filtering unsuitable. The new method assumes a signal model and performs denoising by filtering the signal of each channel using a time-variable filter which is an estimate of the Wiener filter. The approximate Wiener filters are obt