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Fitness costs of an immune response in the house martin (Delichon urbica)

Immune responses constitute a major way for hosts to defend themselves against parasites. Because hosts do not habitually produce strong responses all the time, immune responses might be costly to produce or maintain. We tested experimentally if the production of a response to a challenge with a novel antigen resulted in a cost in terms of fitness using the highly colonial house martin Delichon ur

Nalkas psykologin människan från fel håll?

Does psychology approach personality from the wrong direction? The present text argues that conventional personality psychology, spproaching its object of study from "above", i.e., mapping out the individual´s consciously held attitudes and view of him-/herself, has chosen the wrong path to a tenable science of personality. The alternative would be to scrutinize the processes by which the perceive

Dispersive effective material parameters

The author studied how effective material parameters call be defined for Maxwell's equations when taking dispersion into account. The reasoning is based oil the concept of dispersion relations, and is consequently primarily concerned with lossless media. The author essentially required that the effective material parameters should produce the same dispersion relations as the heterogeneous problem,

Use of history science methods in exposure assessment for occupational health studies

Aims: To show the power of history science methods for exposure assessment in occupational health studies, using the dry cleaning industry in Denmark around 1970 as the example. Methods: Exposure data and other information on exposure status were searched for in unconventional data sources such as the Danish National Archives, the Danish Royal Library, archives of Statistics Denmark, the National

Peak power reduction for OFDM systems with orthogonal pilot sequences

In this paper, a novel peak-to-average power reduction approach for orthogonal frequency division multiplexing (OFDM) has been addressed. Two-dimensional pilot-symbol assisted modulation (2D-PSAM) is employed in coherent OFDM for channel estimation, and it is based on inserting known symbols spread throughout the 2D time-frequency grid. These pilot symbols are employed to simultaneously perform di

End-to-side nerve repair in the upper extremity of rat.

The end-to-side nerve-repair technique, i.e., when the distal end of an injured nerve is attached end-to-side to an intact nerve trunk in an attempt to attract nerve fibers by collateral sprouting, has been used clinically. The technique has, however, been questioned. The aim of the present study was to investigate end-to-side repair in the upper extremity of rats with emphasis on functional recov

Can genital-tract human papillomavirus infection and cervical cancer be prevented with a vaccine?

Human papillomavirus (HPV) infection is the cause of squamous cell carcinoma of the uterine cervix. This causative relationship has provided the rationale and incentive for development of a prophylactic vaccine. Such a vaccine, if found to be effective, could reduce the need for cervical cancer screening and have a profound effect on the incidence of cervical and other anogenital cancers. This rev

Den rationella inbrottstjuven? : En studie om rationalitet och rationellt handlande i brott

Popular AbstractStudien behandlar temat rationalitet och bostadsinbrott. Ett syfte har varit att undersöka rationalitet och rationellt handlande. Rationalitetsbegreppet är komplext och diskuteras och definieras olika i litteraturen. Den teoretiska referensramen har utgjorts av rationalitetsteorier, främst de s.k. Rational Choice-teorierna. Den grundläggande betydelse som rationalitet fått i detta Rationality as purposive action among burglars is the theme of this study. Various theories concerning rationality, Rational Choice Theory especially, are discussed. The first purpose of this thesis is to highlight the concept of rationality. Rationality is a complex concept and it is defined in various ways in the literature. The basic definition is to act in a purposive way towards a defined goa

Ultrafast dynamics of singlet-singlet and singlet-triplet exciton annihilation in poly(3-2 '-methoxy-5 '-octylphenyl)thiophene films

Singlet-singlet (S-S) and singlet-triplet (S-T) exciton annihilation was studied in poly(3-2(')-methoxy-5(')octylphenyl)thiophene films. For the S-S exciton annihilation studies, transient absorption spectroscopy at excitation laser pulse fluences of 1.2x10(13)-4.4x10(14) photons/cm(2) and 2.5 kHz pulse repetition rate was applied. The obtained kinetics demonstrate a typical nonexponential charact

Design of a reverse osmosis plant for leachate treatment aiming for safe disposal

Leachate treatment is one of the major environmental issues faced by landfill owners. One promising method for reduction of pollutant discharge is reverse osmosis (RO). RO technology was tested at a pilot plant at Hedeskoga Landfill in southern Sweden. This landfill receives municipal solid waste (MSW) and industrial, commercial and institutional (IC&I) waste, and produces about 3000 m3/ha of

CCK regulates pancreatic enzyme secretion via short duodenal-pancreatic reflexes in pigs

Background: Different routes of administration of CCK-33 and blockage of CCK-A and muscarinic (m(3)) receptors are used in this study to evaluate the mechanisms by which cholecystokinin can stimulate the exocrine pancreas. Methods: The experiment was performed on eight anaesthetized pigs during control conditions and after administration of the CCK-A and m(3) receptor antagonists, Tarazepide and 4

Endogenous substrates utilized by rat brain in severe insulin-induced hypoglycemia

Several previous studies have demonstrated that severe hypoglycemia is accompanied by consumption of endogenous brain substrates (glycolytic and citric acid cycle metabolites and free amino acids) and some have shown a loss of structural components as well, notably phospholipids. In the present study, on paralysed and artificially ventilated rats, we measured cerebral oxygen and glucose consumptio

Amperometric detection of mono- and diphenols at Cerrena unicolor laccase-modified graphite electrode: correlation between sensitivity and substrate structure

Graphite electrode modified with laccase from Cerrena unicolor served as a biosensor for detection of 30 phenolic compounds with different structures. Some correlations of the sensor response to the structures of substrates are discussed. This biosensor responded to: (i) nanomolar concentrations of some of the selected phenolic compounds, e.g., 2,6-dimethoxyphenol,coniferyl alcohol, caffeic acid,