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Evolution and maintenance of pollen-colour dimorphisms in Nigella degenii: habitat-correlated variation and morph-by-environment interactions

Dimorphism in pollen colour is rare among flowering plants, but occurs in two geographically and morphologically distinct subspecies of Nigella degenii (Ranunculaceae). We evaluated the role of genotype-by-environment interactions in the maintenance of two pollen morphs within each of these subspecies. Morph frequencies in a number of populations were related to current habitat conditions, and an

Computer simulation allows goal-oriented mechanical ventilation in acute respiratory distress syndrome

Introduction To prevent further lung damage in patients with acute respiratory distress syndrome ( ARDS), it is important to avoid overdistension and cyclic opening and closing of atelectatic alveoli. Previous studies have demonstrated protective effects of using low tidal volume ( VT), moderate positive end-expiratory pressure and low airway pressure. Aspiration of dead space ( ASPIDS) allows a r

Decay kinetic properties of atoms in photonic crystals with absolute gaps

Decay kinetic properties of a two-level atom near the band edges of photonic crystals (PCs) with absolute gaps are studied based on the Green's function expression for the evolution operator. The local coupling strength between the photons and an atom is evaluated by an exact numerical method. It is found that the decay behavior of an excited atom can be fundamentally changed by the variation of t

Differential expression of cysteine and aspartic proteases during progression of atherosclerosis in apolipoprotein E-deficient mice

Several groups of proteolytic enzymes are able to degrade components of the extracellular matrix. During atherosclerosis, matrix remodeling is believed to influence the migration and proliferation of cells within the plaque. In the present study, gene expression of several proteases and their inhibitors was analyzed during the development of atherosclerosis in apolipoprotein E-deficient (ApoE-/-)

Determination of magnetic properties of rocks by analysis of demagnetization curves: Hematite-ilmenite bearing rocks from SW Sweden

Granulites from the high-grade Sveconorwegian (corresponding to Grenvillian) gneiss terrane of SW Sweden were investigated in order to relate magnetic properties to the granulite facies mineralogy and the amphibolite facies retrograde mineralogy. We used standard paleomagnetic techniques, susceptibility measurements, electron and optical microscopy, and a new way to analyze demagnetization curves

Bone marrow-derived microglia play a critical role in restricting senile plaque formation in Alzheimer's disease

Microglia are the immune cells of the brain. Here we show a massive infiltration of highly ramified and elongated microglia within the core of amyloid plaques in transgenic mouse models of Alzheimer's disease (AD). Many of these cells originate from the bone marrow, and the beta-amyloid-40 and -42 isoforms are able to trigger this chemoattraction. These newly recruited cells also exhibit a specifi

Chilled ceiling displacement ventilation design charts correlations to employ in optimized system operation for feasible load ranges

This paper expands Ghaddar et al. [N. Ghaddar, K. Ghali, R. Saadeh, A. Keblawi, Design charts for combined chilled ceiling displacement ventilation system (1438-RP), ASHRAE Transactions, 143 (2) (2008) 574-587] design charts of combined chilled ceiling (CC) displacement ventilation (DV) system to operating sensible load ranges from 40 W/m(2) to 100 W/m(2). It develops a global correlation of syste

LCA queries in directed acyclic graphs

We present two methods for finding a lowest common ancestor (LCA) for each pair of vertices of a directed acyclic graph (dag) on n vertices and m edges. The first method is surprisingly natural and solves the all-pairs LCA problem for the input dag on n vertices and m edges in time O(nm). As a corollary, we obtain an O(n(2))-time algorithm for finding genealogical distances considerably improving

Feasibility of a branched stent-graft in common iliac artery aneurysms.

Purpose: To evaluate the short-term feasibility, efficacy, and safety of a modular bifurcated stent-graft with an internal iliac artery (IIA) side branch for endovascular repair of aortoiliac aneurysms. Methods: Between 2002 and 2005, 10 male patients (median age 75 years, range 59–83) were treated with a bifurcated stent-graft that included a unilateral side branch for the IIA. The median diamet

Postmodern vitalism: från D'Arcy Thompson till Mandelbrot

Man har gett namnet ”vitalister” till de tänkare som tillskriver den levande materian en särskild status. Den särskilda statusen kräver vissa uppoffringar. Vitalismen är tvungen att erkänna ett orsaksbegrepp som avviker markant från det dominerande mekanistiska modellen i det modernistiska programmet. Den vitala ”kraften” eller ”principen”, agerar genom den organiska vävnaden för att orsaka den rö

Impact of chronic illness in children on parental living conditions. A population-based study in a Swedish primary care district

In a geographically defined child population aged 0-15, every twelfth child suffered from chronic illness. Their parents and randomly selected control children's parents were asked about their living conditions using questionnaires. Non-responders (30%) had the same sociodemographic profile as responders. The socioeconomic level in index families (n = 95) was lower than in control families (n = 16

Colonization of plant roots by egg-parasitic and nematode-trapping fungi

• The ability of the nematode-trapping fungus Arthrobotrys oligospora and the nematode egg parasite Verticillium chlamydosporium to colonize barley (Hordeum vulgare) and tomato (Lycopersicum esculentum) roots was examined, together with capability of the fungi to induce cell wall modifications in root cells. • Chemotropism was studied using an agar plate technique. Root colonization was investiga

Primary care patients with musculoskeletal pain. Value of health-status and sense-of-coherence measures in predicting long-term work disability

OBJECTIVE: To investigate long-term sick leave among primary care patients with musculoskeletal disorders and the predictive value of health-status and sense-of-coherence measures. METHODS: Patients aged 17 to 64 years who, during seven weeks, attended one of six primary care centers because of non-traumatic musculoskeletal pain and who completed the SF-36 health questionnaire and the sense of coh

Early cerebral metabolic and electrophysiological recovery during controlled hypoxemic resuscitation in piglets

We tested the hypothesis that controlled hypoxemic resuscitation improves early cerebral metabolic and electrophysiological recovery in hypoxic newborn piglets. Severely hypoxic anesthetized piglets were randomly divided into three resuscitation groups: hypoxemic, 21% O2, and 100% O2 groups (8 in each group). The hypoxemic group was mechanically ventilated with 12-18% O2 adjusted to achieve a cere