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Size dependent fragmentation of argon clusters in the soft x-ray ionization regime.

Photofragmentation of argon clusters of average size ranging from 10 up to 1000 atoms is studied using soft x-ray radiation below the 2p threshold and multicoincidence mass spectroscopy technique. For small clusters (N=10), ionization induces fast fragmentation with neutral emission imparting a large amount of energy. While the primary dissociation takes place on a picosecond time scale, the fragm

Detection of short lived radioisotopes as a fast diagnostic for intense laser-solid interactions

As a diagnostic of high-intensity laser interactions (> 10(19) W cm(-2)), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to meas

Significant others of persons with mental health problems: The testing of a questionnaire on the burden of significant others

The importance of family and friends for patients with mental health problems has been recognized over the past few years. Significant others (SO) of patients admitted to a psychiatric ward specializing in affective disorders and suicide prevention filled in a self-rating questionnaire concerning their burden as SOs, the Involvement Evaluation Questionnaire (IEQ). The aims of this study were twofo

The structure and function of the vegetative mycelium of ectomycorrhizal plants .3. Ultrastructural and autoradiographic analysis of inter-plant carbon distribution through intact mycelial systems

Plants of Pinus sylvestris L. were grown in mycorrhizal association with Suillus bovinus (Fr.) O. Kuntze in observation chambers until an interconnecting mycelial network had developed between the seedlings. The shoot of an individual seedling was then sealed in a perspex cuvette and exposed to 14CO2. After incubation for 48 h, the 'donor' shoot was removed and components of the mycelial network a

Combustion process in a biomass grate fired industry furnace: a CFD study

This paper presents a CFD investigation of the combustion process in a 50 MW grate fired furnace. The CFD results were compared with available experimental data at the furnace Outlet to validate the models for the volatile oxidation and NOx formation. The models were then used to predict the effect of a 'ECO' tube system on NOx emissions. It was shown that with an improved flow structure and air d

Influences of Family Based Prerequisites, Reading Attitude, and Self-Regulation on Reading Ability

This study investigated the effect of self-regulated learning, as indicated by academic self-concept, motivation and learning strategies, reading attitude and family based prerequisites on reading ability. Students (n=4018) in the eighth grade answered the IEA reading literacy test, the self-regulated learning questionnaire and a student questionnaire about their background. The exploratory factor

Mitotic instability in cancer - Is there method in the madness?

It has been known for more than a century that neoplastic cells often exhibit disturbances of the mitotic process, but the causes have only recently been thoroughly explored. In many cancers, a combination of cell cycle checkpoint deficiency and abnormal shortening of telomeres predisposes to unbalanced chromosome segregation at cell division and the development of complex genomic rearrangements.

Scope of nucleotide chemistry as studied by isothermal titration microcalorimetry

The area of isothermal titration microcalorimetric (ITC) studies on solution systems involving nucleotides is reviewed. 62 references are cited. About 25 ITC studies on nucleotide systems have been published during the last two decades. The main part (ca 95%) of these papers deal with nucleotide-protein interactions and one paper involves nucleotide-nucleotide binding studies. The results of such

Neuronal death in nigral grafts in the absence of poly (ADP-ribose) polymerase activation

The exact causes of the extensive cell death in nigral transplants are still unknown. Since poly-(ADP-ribose) polymerase (PARP) overactivation has been implicated in neuronal death, we examined the effects of PARP on the survival of nigral grafts by using donor tissue from PARP knock-out or wild-type mice. Eight hours after preparation of the nigral cell suspension, cell damage was quantified by m

Concentrations of Metals, beta-Amyloid and Tau-Markers in Cerebrospinal Fluid in Patients with Alzheimer's Disease

Background/Aims: In this study, metal concentrations were related to the levels of well-known Alzheimer markers in cerebrospinal fluid (CSF), such as amyloid-beta (A beta), total tau (T-tau) and phosphorylated-tau (P-tau). Methods: Concentrations of 19 metals (Mg, Ca, V, Mn, Fe, Co, Ni, Cu, Zn, Se, Rb, Sr, Mo, Cd, Sn, Sb, Cs, Hg and Pb by inductively coupled plasma-mass spectrometry) and the level

Large scale differentiation and population dynamics in tundra plants and vegetation

The inclusion of the botanical projects in the Swedish-Russian Tundra Ecology -94 expedition provided new information on the ecology of tundra plants. The vegetation patterns on different scales were documented, and interpreted as the result of a complex interaction with environmental factors. The distribution of fruticose lichens was studied, and it was shown that these lichens rely on different

Traveling Architects – A New Way of Herding Cats

Making software developers work towards a common goal may be likened to herding cats. If we further spread developers around the globe, we run increased risks of being unable to design and impose coherent software architectures on projects, potentially leading to lower quality of the resulting systems. Based on our experiences in a large, distributed research and development project, PalCom, we pr

Self-diffusion of nonfreezing water in porous carbohydrate polymer systems studied with nuclear magnetic resonance

Water is an integral part of the structure in biological porous materials such as wood and starch. A problem often encountered in the preparation of samples for, e.g., electron microscopy is that removal of water leads to a decreasing distance between supermolecular structural elements and a distortion of the structure. It is, therefore, of interest to find methods to investigate these materials i

Jump Spillover in International Equity Markets

In this article we study jump spillover effects between a number of country equity indexes. In order to identify the latent historical jumps of each index, we use a Bayesian approach to estimate a jump-diffusion model on each index. We look at the simultaneous jump intensities of pairs of countries and the probabilities that jumps in large countries cause jumps or unusually large returns in other

Measured CMOS Switched High-Quality Capacitors in a Reconfigurable Matching Network

Switched capacitors are here investigated for use in reconfigurable matching networks, particularly for DVB-H frequencies. A 0.13 um CMOS circuit is evaluated through both simulations and measurements. Source grounded NMOS transistors are used to switch high quality metal capacitors located above metal layer 8. The quality factor and tuning range depend on frequency, switch voltage, capacitor size

Effects of grassland abandonment, restoration and management on butterflies and vascular plants

When semi-natural pastures are abandoned, specialized grassland species are lost as a consequence of succession. As a counter-measure, previously abandoned grasslands may be restored by clearing shrubs and trees and re-introducing grazing livestock. In order to examine the effects of this type of habitat restoration, we compared species richness of plants and of specialized plants thought to be de

Sample preparation effects on the compaction properties of Swedish fine-grained tills

Fine-grained tills are a dominant feature of the drift geology of Sweden. Until recently their use in earthworks applications has been limited due to the plentiful supply of naturally occurring gravel and crushed rock, and their high sensitivity to moisture content change which often leads to the view that fine-grained tills are problem soils. Environmental and economic factors are, however, leadi