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The collapse of cycles in the dynamics of North American grouse populations

Cyclic dynamics of bird and mammal populations are commonly reported in northern latitudes throughout the world, and recent European observations on rodents and grouse suggest that cycle periods decline towards southern latitudes. To investigate latitudinal patterns of cyclic dynamics in North America, we assembled 27 long-term data sets collected between 1939 and 2001 for three grouse species. By

HIV-1 Nef mimics an integrin receptor signal that recruits the polycomb group protein Eed to the plasma membrane

The Nef protein of human and simian immunodeficiency virus (HIV/SIV) is believed to interfere with T cell activation signals by forming a signaling complex at the plasma membrane. Composition and function of the complex are not fully understood. Here we report that Nef recruits the Polycomb Group (PcG) protein Eed, so far known as a nuclear factor and repressor of transcription, to the membrane of

Optimizing factor prophylaxis for the haemophilia population: where do we stand?

The hallmark of severe haemophilia, defined as a circulating level of factor (F) VIII (haemophilia A cases) or FIX (haemophilia B cases) of < 1%, is recurrent bleeding into muscles and joints (haemarthroses) from an early age of life. The inevitable result of such bleeding is progressive joint damage, leading to disabling arthritis that is typically evident within the first 2 decades of life in pe

Spread of synaptic activity along parallel fibres in cat cerebellar anterior lobe

1. Mossy fibre evoked activity in the cerebellar cortex elicited by peripheral electrical stimulation was studied in chloralose anesthetized cats. The distribution of intracortical field potentials in the C3 and D zones was mapped in order to determine if there is a spread of synaptic activity outside the mossy fibre termination area. This area was identified by the presence of short latency synap

Nestling growth and song repertoire sire in great reed warblers: evidence for song learning as an indicator mechanism in mate choice

Females of many songbird species show a preference for mating with males that have larger song repertoires, but the advantages associated with this preference are uncertain. We tested the hypothesis that song complexity can serve as an indicator of male quality because the development of the brain regions underlying song learning and production occurs when young birds typically face nutritional an

Familial risks in nervous-system tumours: a histology-specific analysis from Sweden and Norway

Background There are limited data available on tumour subtype-specific familial risks for nervous-system tumours. We aimed to provide such data at the population level. Methods We used data from the nationwide Swedish and Norwegian databases on familial cancer to calculate standardised incidence ratios (SIRS) for the familial risk of developing a nervous-system tumour in offspring born after 1931

Key factors for human islet isolation and clinical transplantation

Background. To further improve the outcome of clinical islet transplantation analysis of the impact of donor- and process-related factors could be of great importance. Materials and Methods. Thirty-eight consecutive clinical islet transplantations were performed with consecutive islet isolations. Univariate analysis for donor- and isolation-related variables were correlated with recipient C-peptid

Identity regulation as organizational control: Producing the appropriate individual

This paper takes the regulation of identity as a focus for examining organizational control. It considers how employees are enjoined to develop self-images and work orientations that are deemed congruent with managerially defined objectives. This focus on identity extends and deepens themes developed within other analyses of normative control. Empirical materials are deployed to illustrate how man

Comparison of SO2 and H2SO4 impregnation of softwood prior to steam pretreatment on ethanol production

The pretreatment of softwood with sulfuric acid impregnation in the production of ethanol, based on enzymatic hydrolysis, has been investigated. The parameters investigated were: H2SO4 concentration (0.5-4.4% w/w liquid), temperature (180-240 degrees C), and residence time (1-20 minutes). The combined severity (log Ro-pH) was used to combine the parameters into a single reaction ordinate. The high

Differences in prolactin receptor (PRLR) in mouse and human fallopian tubes: Evidence for multiple regulatory mechanisms controlling PRLR isoform expression in mice

The anterior pituitary-derived hormone prolactin (PRL) signals through the PRL receptor (PRLR) and is important for female reproductive function in mammals. In contrast to the extensive studies of PRLR expression and regulation in human and mouse ovary and uterus, the mechanisms controlling the regulation of PRLR isoform expression in the fallopian tube are poorly understood. Because dynamic inter

Automated reporting from gel-based proteomics experiments using the open source Proteios database application

The assembly of data from different parts of proteomics workflow is often a major bottleneck in proteomics. Furthermore, there is an increasing demand for the publication of details about protein identifications due to the problems with false-positive and false-negative identifications. In this report, we describe how the open-source Proteios software has been expanded to automate the assembly of

Propagation in bianisotropic media-reflection and transmission

A systematic analysis for solving the wave propagation problem in a general bianisotropic, stratified medium is presented. The method utilises the concept of propagators, and the representation of these operators is simplified by introducing the Cayley-Hamilton theorem. The propagators propagate the total tangential electric and magnetic fields in the slab and only outside the slab do the up- and

Lunar dust: A negative control for biomarker analyses of extraterrestrial samples?

The purpose of this study was to assess, for the first time, the presence of muramic acid (Mur) and 3-hydroxy fatty acids (3-OH FAs), chemical markers for terrestrial bacteria in "curated" lunar samples by use of state-of-the-art gas chromatography-tandem mass spectrometry. The Apollo lunar sample collection has been stored, under isolation conditions, at the Johnson Space Center since 1969. Marke

Pain relief after esophagectomy: Thoracic epidural analgesia is better than parenteral opioids

OBJECTIVE: To compare postoperative pain relief and pulmonary function in patients after thoracoabdominal esophagectomy treated by continuing perioperative thoracic epidural anesthesia or changing to parenteral opioids. DESIGN: Prospective, randomized study. SETTING: University teaching hospital. PARTICIPANTS: Thirty-three patients undergoing thoracoabdominal esophagectomy. INTERVENTIONS: General

Seizure suppression in kindling epilepsy by intracerebral implants of GABA- but not by noradrenaline-releasing polymer matrices

Gamma-aminobutyric acid (GABA)-releasing polymer matrices were implanted bilaterally, immediately dorsal to the substantia nigra, in rats previously kindled in the amygdala. Two days after implantation, rats with GABA-releasing matrices exhibited only focal limbic seizures in response to electrical stimulation, whereas animals with control matrices devoid of GABA had generalized convulsions. GABA

Impact of transposable elements on the evolution of mammalian gene regulation.

Transposable elements (TEs) are present in all organisms and nearly half of the human and mouse genome is derived from ancient transpositions. This fact alone suggests that TEs have played a major role in genome organization and evolution. Studies undertaken over the last two decades or so clearly show that TEs of various kinds have played an important role in organism evolution. Here we review th