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Determinants of local ant (Hymenoptera: Formicidae) species richness and activity density across Europe
1. Species richness is influenced by local habitat features and large-scale climatic gradients. Usually, both influences are studied in isolation because of the divergent spatial scales at which they occur. Here, we compared the influence of large-scale climate and local habitat type on European ants using a continent-wide, standardised sampling programme. 2. We investigated species richness and a
Hepatic and extrahepatic malignancies in primary sclerosing cholangitis
Background/Aims: To assess the risk of hepatic and extrahepatic malignancies in a large cohort of Swedish primary sclerosing cholangitis (PSC) patients compared with that of the general Swedish population. Methods: The study cohort comprised 604 PSC patients identified between 1970 and 1998. Follow-up was provided through linkages to the Swedish Cancer and Death registries. Cumulative incidence of
Fast kriging of large data sets with Gaussian Markov random fields
Abstract in Undeterminedpatial data sets are analysed in many scientific disciplines. Kriging, i.e. minimum mean squared error linear prediction, is probably the most widely used method of spatial prediction. Computation time and memory requirement can be an obstacle for kriging for data sets with many observations. Calculations are accelerated and memory requirements decreased by using a Gaussian
Phase Behavior in Aqueous Two-Phase Systems Containing
The phase behavior of the three-component PEO-PPO-PEO/dextradwater system has been studied. Pluronic L64, P105, and F68 were used, and they are members of a family of triblock copolymers with the structure PEO-PPO-PEO, where PEO is poly(ethy1ene oxide) and PPO poly- (propylene oxide). Moreover, these triblock copolymers tend to self-aggregate in aqueous solution at increasing temperature. The phas
The global burden of diabetic foot disease
Diabetic foot problems are common throughout the world, resulting in major economic consequences for the patients, their families, and society. Foot ulcers are more likely to be of neuropathic origin, and therefore eminently preventable, in developing countries, which will experience the greatest rise in the prevalence of type 2 diabetes in the next 20 years. People at greatest risk of ulceration
Improved acetabular pressurization gives better cement penetration - In vivo measurements during total hip arthroplasty
During total hip arthroplasty, the intraoperative cementation pressure was measured inside one of the acetabular anchorage holes. Patients were randomized to pressurization of cement with either a conventional pressurizer or a sequential method including individual pressurization of each anchorage hole. The pressure was correlated to the cement penetration measured on digital radiographs. The earl
Combined lack of estrogen receptors alpha and beta affects vascular iNOS protein expression.
Endothelial and vascular smooth muscle cells express both estrogen receptor (ER) agr and beta. Recent findings indicate that vascular ERbeta and ERagr may substitute for one another. Here, we investigate vascular morphology, contractility and protein expression in intact aorta from adult (4 months old) female mice lacking both ERagr and ERbeta (DERKO). The body weights were 17% higher (P
Basal metabolic rate and the evolution of the adaptive immune system
Vertebrates have evolved an adaptive immune system in addition to the ancestral innate immune system. It is often assumed that a trade-off between costs and benefits of defence governs the evolution of immunological defence, but the costs and benefits specific to the adaptive immune system are poorly known. We used genetically engineered mice lacking lymphocytes (i.e. mice without adaptive, but wi
Differential Akt activation in the photoreceptors of normal and rd1 mice.
Retinitis pigmentosa is a blinding disease in which unknown mechanisms cause the degeneration of retinal photoreceptors. The retinal degeneration (rd1) mouse is a relevant model for this condition, since it carries a mutation also found in some forms of retinitis pigmentosa. To understand the degenerative process in the rd1 mouse, we must identify the survival and apoptosis-related signaling pathw
Effect of electrical stimulation on the activity of muscle exoproteases during beef ageing
Electrical stimulation was applied to bull carcasses at a low voltage (80 V, 15 Hz, 30 s). The pH decline, tenderness, myofibrillar protein degradation, and exoprotease activities were studied in semimembranosus and longissimus dorsi muscles during the ageing process. Electrical stimulation was found to be beneficial for tenderness in longissimus dorsi muscle as determined by shear force and confi
Genetic and morphological variation in Dunlin Calidris alpina breeding in the Palearctic tundra
The extensive overlap in morphological characters between populations of Dunlin Calidris alpina imposes problems of determining the origin of migrating and wintering birds. The morphology of the birds also varies between the sexes, and the sex of a Dunlin may often be difficult to determine. To clarify if mitochondrial DNA can be used to identify which breeding areas migrating Dunlin come from, we
Generating positrons with femtosecond-laser pulses
Utilizing a femtosecond table-top laser system, we have succeeded in converting via electron acceleration in a plasma channel, low-energy photons into antiparticles, namely positrons. The average intensity of this source of positrons is estimated to be equivalent to 2x10(8) Bq and it exhibits a very favorable scaling for higher laser intensities. The advent of positron production utilizing femtose
Decreases in myocardial glucose and increases in pyruvate but not ischaemia are observed during porcine endotoxaemia.
Myocardial dysfunction occurs commonly in septic shock. It is not known whether this is due to local ischaemia and metabolic disturbances. Our hypothesis was that endotoxaemic myocardial dysfunction may be associated with interstitial ischaemic and metabolic changes, measured using interstitial microdialysis (MD). Methods: Eighteen pigs were randomized to control (n=6) or endotoxin infusion (n=12)
A new understanding of au-assisted growth of III-V semiconductor nanowires
Semiconductor nanowires of III-V materials have generated much interest in recent years. However, the growth mechanisms by which these structures form are not well understood. The so-called vapor-liquid-solid (VLS) mechanism has often been proposed for III-V systems, with a chemically inert, liquid metal particle (typically Au) acting as a physical catalyst. We assert here that An is, in fact, not
More pronounced salt dependence and higher reactivity for platination of the hairpin r(CGCGUUGUUCGCG) compared with d(CGCGTTGTTCGCG)
The DNA interference pathways exhibited by cisplatin and related anticancer active metal complexes have been extensively studied. Much less is known to what extent RNA interaction pathways may operate in parallel, and perhaps contribute to both antineoplastic activity and toxicity. The present study was designed with the aim of comparing the reactivity of two model systems comprising RNA and DNA h
Country of birth, instrumental activities of daily living, self-rated health and mortality: a Swedish population-based survey of people aged 55-74.
There is scant knowledge of the effects of country of birth on the health of individuals in the years prior to and after retirement. The aim of this study was to consider country of birth in relation to health status, instrumental activities of daily living (IADL) and all-cause mortality when adjusted for socioeconomic status (SES). Cross-sectional data were collected between 1986 and 1991 on 8959
Genetic Variation in Brain-Derived Neurotrophic Factor Is Associated with Serotonin Transporter but Not Serotonin-1A Receptor Availability in Men
Background: The serotonergic system, including the serotonin transporter (5-HTT), which is the target of many antidepressants, seems to be influenced by brain-derived neurotrophic factor (BDNF). Methods: Positron emission tomography (PET) was used to address, in 25 and 53 healthy volunteers, respectively, the possible association between six polymorphisms in the gene encoding BDNF and the availabi
Economic evaluation of enzymatic hydrolysis of phenol-pretreated wheat straw
Experimental data from the enzymatic hydrolysis of phenol-pretreated Swedish wheat straw have been used to evaluate the cost fractions of capital and utility, enzyme, and raw material. Two different raw material prices and varying enzyme prices have been used. The evaluation is based on an empirical model for the enzymatic hydrolysis and a computer program where utility and equipment, enzyme, and
Time-dependent radiative transfer in magneto-optical traps
We investigate radiation-imprisonment (RI) phenomena in a system of cold atoms trapped in magneto-optical traps (MOTs) when cooling lasers are switched off for a short period. The problem is formulated within the framework of the Streater-Cooper-Sandle equation that belongs to the Markov class and accounts for photon frequency redistribution in multiple scattering processes. On the basis of a semi