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The predissociation of highly excited states in acetylene by time-resolved photoelectron spectroscopy

We study the dynamics of highly excited states in acetylene initiated by an ultrashort vacuum ultraviolet laser pulse. Electronic states lying in the 4s-3d Rydberg region are excited with one femtosecond pulse, and the dynamic development of the states is monitored by a second short pulse which ionizes the system. We show that even for femtosecond pulses where the bandwidth of the exciting pulse c

Spatial Influence of Topographical Factors on Yield of Potato (Solanum Tuberosum L.) in Central Sweden

This study has evaluated the sampling density for creation of high-resolution digital elevation models (DEMs) for precision agriculture purposes. The relationships between yield and topographical factors were investigated in a study area located in the central Sweden province of Dalarna. The DEM data sampling was carried out with a RTK-GPS system. A dense sampling scheme was employed and data was

Random environment on coloured trees

In this paper, we study a regular rooted coloured tree with random labels assigned to its edges, where the distribution of the label assigned to an edge depends on the colours of its endpoints. We obtain some new results relevant to this model and also show how our model generalizes many other probabilistic models, including random walk in random environment on trees, recursive distributional equa

Experimental and theoretical evidence of overcharging of calcium silicate hydrate

Electrokinetic measurements such as electrophoresis may show an inversion of the effective surface charge of colloidal particle called overcharging. This phenomenon has been studied by various theoretical approaches but up to now very few attempts of confrontation between theory and experiment have been conducted. In this work we report electrophoretic measurements as well as Monte Carlo simulatio

Pressurized hot water extraction of insecticides from process dust - Comparison with supercritical fluid extraction

Pressurized hot liquid water and steam were used to investigate the possibilities of extracting insecticides (carbofuran, carbosulfan, and imidacloprid) from contaminated process dust remaining from seed-pellet production. Extraction temperature was the most important parameter in influencing the extraction efficiency and rate of extraction, while varying the pressure had no profound effect. A cle

A label of health: a previous immune challenge is reflected in the expression of a female plumage trait.

Studies of ornaments as indicators of individual quality have hitherto focused on males, while studies of female ornaments have been almost absent. However, females within the same species may show large variation in both outer appearance and individual quality. We experimentally examined the effect of an immune challenge on the size of white fringes in the wing feathers produced one to two months

Stability characteristics of a calcium-independent alkaline protease from Nesterenkonia sp.

Thermodynamic stability of an alkaline protease from a new alkaliphilic Nesterenkonia sp. AL-20, was investigated and compared with that of Subtilisin Carlsberg. The amount of calcium bound to the AL-20 protease was determined to be only about 0.14 mol/mol of protease. Differential scanning calorimetry scan of the enzyme at increasing temperature showed the denaturation of the enzyme to be a two-s

Islet amyloid polypeptide inhibits glucagon release and exerts a dual action on insulin release from isolated islets.

We have studied the influence of a wide concentration range of islet amyloid polypeptide (IAPP) on both glucagon and insulin release stimulated by various types of secretagogues. In an islet incubation medium devoid of glucose, the rate of glucagon release being high, we observed a marked suppressive action by low concentrations of IAPP, 10−10 and 10−8 M, on glucagon release. Similarly, glucagon r

Evidence for microbunching "sidebands" in a saturated free-electron laser using coherent optical transition radiation

We report the first measurements of z -dependent coherent optical transition radiation (COTR) due to electron-beam microbunching at high gains (>10(4) ) including saturation of a self-amplified spontaneous emission free-electron laser (FEL). In these experiments the fundamental wavelength was near 530 nm, and the COTR spectra exhibit the transition from simple spectra to complex spectra (5% spectr

A BAP1 Mutation in a Danish Family Predisposes to Uveal Melanoma and Other Cancers

Truncating germline mutations in the tumor suppressor gene BRCA-1 associated protein-1 (BAP1) have been reported in families predisposed to developing a wide range of different cancer types including uveal melanoma and cutaneous melanoma. There has also been an association between amelanotic tumor development and germline BAP1 mutation suggesting a possible phenotypic characteristic of BAP1 mutati

Efficient Generation of Hematopoietic Precursors and Progenitors From Human Pluripotent Stem Cell Lines.

By mimicking embryonic development of the hematopoietic system, we have developed an optimized in vitro differentiation protocol for the generation of precursors of hematopoietic lineages and primitive hematopoietic cells from human embryonic stem cells (ES) and induced pluripotent stem cells (iPS). Factors such as cytokines, extra cellular matrix components, and small molecules, as well as the te

cis-Bis(acetato-kO)bis(dimethyl sulfide-kS)platinum(II)

The title compound, cis-[Pt(CH3COO)2(C2H6S)2], crystallizes in the P21/c space group with a pseudo-square-planar geometry. The complex forms centrosymmetric dimeric packing units, with C-H...O-Pt interactions and a short Pt...Pt distance [3.5868(2) Å]. The coordination mode of the acetate ligands is monodentate and they are oriented almost perpendicular to the coordination plane. Cambridge Structu

The 'informal sector' and the political economy of development

This paper takes an initial step in integrating insights from two sets of literature which have focused on central aspects of development with unfortunate independence. It highlights politically valuable resources, which are identified in the political economy literature, and shows that the informal sector literature provides ample evidence that these resources in general are (i) scarcely availabl

Candelariella (Candelariaceae) in western United States and northern Mexico: the 8-spored, lecanorine species

This paper treats 12 Candelariella species occurring in western North America characterized by having lecanorine apothecia and 8-spored asci. Six new names are proposed: C. aggregata, C. californica, C. complanata, C. corallizoides, C. deppeanae and C. inmarginata. Candelariella terrigena and C. deflexa are treated as synonyms of C. citrina and C. aurella, respectively. Candelariella kansuensis is

Role of Aromatic Side Chains in the Binding of Volatile General Anesthetics to a Four-alpha-helix Bundle.

Currently, the mechanism by which anesthesia occurs is thought to involve the direct binding of inhaled anesthetics to ligand-gated ion channels. This hypothesis is being studied using four--helix bundles as model systems for the transmembrane domains of the natural "receptor" proteins. This study concerns the role in anesthetic binding played by aromatic side chains in the binding cavity of a fou

The temporal development of retinopathy and nephropathy in type 1 diabetes mellitus during 15 years diabetes duration

In this prospective study, the 10- and 15-year incidence and course of retinopathy were examined in relation to medical risk indicators from 3.1 +/- 1.9 (mean -/+ SD) years diabetes duration and onwards in 29 adult type 1 diabetic patients treated under routine care. A total of 28 patients were followed for 10 years and 20 patients for 15 years diabetes duration. After 10 years diabetes duration,

Risk assessment of false-positive quantitative real-time PCR results in food, due to detection of DNA originating from dead cells

Real-time PCR technology is increasingly used for detection and quantification of pathogens in food samples. A main disadvantage of nucleic acid detection is the inability to distinguish between signals originating from viable cells and DNA released from dead cells. In order to gain knowledge concerning risks of false-positive results due to detection of DNA originating from dead cells, quantitati