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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

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

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

Simple approach to polyampholytes based on chain polarizabilities

The polarizabilities of polyampholytes have been calculated in Monte Carlo simulations. For chains with random charge topologies, the polarizability increases with the chain length and the chain flexibility. For block copolymers, the polarizability initially increases with the block size to a maximum and then decreases. The polarizability is used to characterize the interaction between polyampholy

Transvascular protein transport in mice lacking endothelial caveolae.

Caveolae are Omega-shaped vesicular structures postulated to play a role in transvascular protein transport. Studies on mice lacking endothelial caveolae, caveolin-1 knockout (Cav-1-KO) mice, indicate increased macromolecular transport rates. This was postulated to be due to the appearance of an alternative pathway. The present study tested whether an alternative pathway had appeared in Cav-1-KO m

The human P-k histo-blood group antigen provides protection against HIV-1 infection

Several human histo-blood groups are glycosphingolipids, including P/P1/P-k. Glycosphingolipids are implicated in HIV-host-cell-fusion and some bind to HIV-gp120 in vitro. Based on our previous studies on Fabry disease, where P-k accumulates and reduces infection, and a soluble P-k analog that inhibits infection, we investigated cell surface-expressed P-k in HIV infection. HIV-1 infection of perip

Absorption and lipoprotein transport of sphingomyelin

Dietary sphingomyelin (SM) is hydrolyzed by intestinal alkaline sphingomyelinase and neutral ceramidase to sphingosine, which is absorbed and converted to palmitic acid and acylated into chylomicron triglycerides (TGs). SM digestion is slow and is affected by luminal factors such as bile salt, cholesterol, and other lipids. In the gut, SM and its metabolites may influence TG hydrolysis, cholestero

Arthrodesis of the ankle secondary to replacement

One hundred total ankle arthroplasties were performed in our department between 1974 and 1994, and of these, 21 have been reoperated on with arthrodesis due to septic or nonseptic failures after 6 months to 15 years (median 40 months). Immobilization using a Hoffman external fixator was the dominating method. The total ankles were of six different designs. Sixteen of the 21 patients suffered from

mRNAs of tyrosine hydroxylase and dopa decarboxylase but not of GD2 synthase are specific for neuroblastoma minimal disease and predicts outcome for children with high-risk disease when measured at diagnosis

Several transcripts have been claimed to be clinically valuable for detecting minimal disease in neuroblastoma, but they have not been prospectively compared in a standardized manner. Tyrosine hydroxylase (TH), dopa decarboxylase (DDC) and GD2 synthase (GD2S) mRNAs were analyzed in 554 blood (PB) and bone marrow (BM) samples from 58 children with neuroblastoma. Samples from 44 children with other

Return of collective rotation in Er-157 and Er-158 at ultrahigh spin

A new frontier of discrete-line gamma-ray spectroscopy at ultrahigh spin has been opened in the rare-earth nuclei Er-157,Er-158. Four rotational structures, displaying high moments of inertia, have been identified, which extend up to spin similar to 65h and bypass the band-terminating states in these nuclei which occur at similar to 45h. Cranked Nilsson-Strutinsky calculations suggest that these s

Patterns in the distribution of Arctic freshwater zooplankton related to glaciation history.

We analysed circumpolar samples from 68 lakes within the 10°C-July isotherm from Arctic Canada, Nunavut, Greenland, Svalbard, Eastern Siberia, the Beringia region, and Alaska. In total, we found 3 species of Anostraca, 17 of Diplostraca, 1 species of cyclopoid and 14 species of calanoid copepods. Our study identifies a wider distribution for some copepods—e.g. Eurytemora pacifica, Leptodiaptomus s

Resistance of flight feathers to mechanical fatigue covaries with moult strategy in two warbler species

Flight feather moult in small passerines is realized in several ways. Some species moult once after breeding or once on their wintering grounds; others even moult twice. The adaptive significance of this diversity is still largely unknown. We compared the resistance to mechanical fatigue of flight feathers from the chiffchaff Phylloscopus collybita, a migratory species moulting once on its breedin

Peak torque and knee kinematics during gait after eccentric isokinetic training of quadriceps in healthy subjects

Objective: To evaluate the effects of eccentric isokinetic training on knee range of motion (ROM) of healthy subjects. Methods: The knee extensor and flexor isokinetic peak torques and ROM of flexion/extension and varus/valgus knee movements during gait of 18 healthy men (21.7 +/- 2.2 years; 1.73 +/- 0.10m; 68.7 +/- 9.4kg; body mass index: 22.6 +/- 2 kg/m(2)) were analyzed, before and after six we

The C-type lectin domains of lecticans, a family of aggregating chondroitin sulfate proteoglycans, bind tenascin-R by protein-protein interactions independent of carbohydrate moiety

The lecticans are a family of chondroitin sulfate proteoglycans including aggrecan, versican, neurocan, and brevican. The C-terminal globular domains of lecticans are structurally related to selectins, consisting of a C-type lectin domain flanked by epidermal growth factor and complement regulatory protein domains. The C-type lectin domain of versican has been shown to bind tenascin-R, an extracel

Dietary Supplementation With Phytohemagglutinin In Combination With Alpha-Ketoglutarate Limits The Excretion Of Nitrogen Via Urinary Tract

The aim of the study was to evaluate the effect of both phytohaemagglutinin (PHA) alone, and in combination with alpha-ketoglutaric acid (AKG), on nitrogen elimination via the urinary tract as opposed to the gastrointestinal tract of rats. In experiment I, rats were assigned to one of two experimental groups, (1) Control and (2) PHA, whilst in experiment 2, rats were assigned to one of three exper