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Improved modeling and bounds for NQR spectroscopy signals

Nuclear Quadrupole Resonance (NQR) is a method of de- tection and unique characterization of compounds containing quadrupolar nuclei, commonly found in many forms of ex- plosives, narcotics, and medicines. Typically, multi-pulse sequences are used to acquire the NQR signal, allowing the resulting signal to be well modeled as a sum of exponentially damped sinusoidal echoes. In this paper, we improv

Systematic trends in beta-delayed particle emitting nuclei: The case of beta p alpha emission from Mg-21

We have observed beta(+)-delayed alpha and p alpha emission from the proton-rich nucleus Mg-21 produced at the ISOLDE facility at CERN. The assignments were cross-checked with a time distribution analysis. This is the third identified case of beta p alpha emission. We discuss the systematic of beta-delayed particle emission decays, show that our observed decays fit naturally into the existing patt

First Trimester Urine and Serum Metabolomics for Prediction of Preeclampsia and Gestational Hypertension: A Prospective Screening Study.

Hypertensive disorders of pregnancy, including preeclampsia, are major contributors to maternal morbidity. The goal of this study was to evaluate the potential of metabolomics to predict preeclampsia and gestational hypertension from urine and serum samples in early pregnancy, and elucidate the metabolic changes related to the diseases. Metabolic profiles were obtained by nuclear magnetic resonanc

Structural and magnetic properties of MnAs/GaAs ferromagnetic semiconductor nanocomposite material

Self-organized (Ga,Mn)As nanoclusters, embedded in GaAs and formed during thermal annealing of Ga1-xMnxAs layer at 500 degrees C or 600 degrees C, were studied using Transmission Electron Microscopy (TEM) and Magnetic Force Microscopy (MFM). We found that 10-20 nm large NiAs-type hexagonal MnAs nanocrystals gave magnetic contrast in MFM images, whereas smaller zinc-blende nanoinclusions were not v

Progress in regional downscaling of west African precipitation

We review the recent progress in dynamical and statistical downscaling approaches for west African precipitation and perform a regional climate model (RCM) intercomparison using the novel multi-model RCM data set from the Ensembles-based Predictions of Climate Changes and Their Impacts (ENSEMBLES) and African Monsoon Multidisciplinary Analyses (AMMA) projects. Present RCMs have distinct systematic

Dynamic metabolomics differentiates between carbon and energy starvation in recombinant Saccharomyces cerevisiae fermenting xylose

Background: The concerted effects of changes in gene expression due to changes in the environment are ultimately reflected in the metabolome. Dynamics of metabolite concentrations under a certain condition can therefore give a description of the cellular state with a high degree of functional information. We used this potential to evaluate the metabolic status of two recombinant strains of Sacchar

Regional Innovation Systems: Theory, Empirics and Policy

ASHEIM B. T., LAWTON SMITH H. and OUGHTON C. Regional innovation systems: theory, empirics and policy, Regional Studies. Interest in regional innovation systems has grown significantly over the past three decades driven partly by advances in theoretical analysis, partly by the growing interest in innovation as a source of competitive advantage, and partly by the need for new policies to address re

Enzymatic Hydrolysis of Organic Phosphates Adsorbed on Mineral Surfaces

Esters of phosphoric acid constitute a sizable fraction of the total phosphorus supply in the environment and thus play an important role in the global phosphorus cycle. Enzymatic hydrolysis of these esters to produce orthophosphate is often a required reaction preceding phosphorus uptake by plants and microorganisms. Generally, adsorption to environmental particles is assumed to limit this proces

Styrmedel för en ökad produktion av gödselbaserad biogas - En fallstudie för Skåne och Västra Götalands län

Produktion av biogas från gödsel har i flera studier visat sig leda till stora positiva miljöeffekter, i synnerhet vad gäller emissioner av växthusgaser, jämfört med andra förnybara energibärare. Skälet är att produktionen av biogas, utöver att ersätta fossila bränslen, också ger en minskad miljöpåverkan från konventionell hantering av stallgödsel. Trots dessa positiva miljöeffekter utnyttjas dock

Variants at the 9p21 locus and melanoma risk

Background: The influence of variants at the 9p21 locus on melanoma risk has been reported through investigation of CDKN2A variants through candidate gene approach as well as by genome wide association studies (GWAS). Methods: In the present study we genotyped, 25 SNPs that tag 273 variants on chromosome 9p21 in 837 melanoma cases and 1154 controls from Spain. Ten SNPs were selected based on previ

Mödrars röster om samordnare i ungdomsvården

Syftet med denna studie är att utifrån mitt empiriska material kartlägga och beskriva hur föräldrar till barn intagna på särskilda ungdomshemmen tolkar, definierar och upplever ett behandlingsprojekt, som involverade olika myndigheter, benämnt Motverka Våld och Gäng. Dessutom uppmärksammas hur de anställda samordnarna uppfattades och kategoriserades av föräldrarna. ”Föräldrar” blir i undersökninThe aim of this study is to analyze how mothers with children placed in Swedish juvenile homes interpret, define and perceive, on the one hand, the project “Motverka Våld och Gäng” meaning “Counteract Violence and Gangs”, and on the other hand the role of the Coordinators employed in this project. The mothers who were interviewed spoke about some Coordinators that they appreciated. They then pain

Bet-hedging as an evolutionary game: the trade-off between egg size and number.

Bet-hedging theory addresses how individuals should optimize fitness in varying and unpredictable environments by sacrificing mean fitness to decrease variation in fitness. So far, three main bet-hedging strategies have been described: conservative bet-hedging (play it safe), diversified bet-hedging (don't put all eggs in one basket) and adaptive coin flipping (choose a strategy at random from a f

The effect of turbidity and prey fish density on consumption rates of piscivorous Eurasian perch Perca fluviatilis

Predator-prey interaction strengths in variable environments constitute a fundamental link to the understanding of aquatic ecosystem responses to environmental change. The present study investigates the effects of visibility conditions and prey fish density on predation rates of visually oriented piscivorous Eurasian perch Perca fluviatilis L. This was done in outdoor mesocosm (16 m(2)) experiment

Measurement of the differential cross section for the two-body photodisintegration of He-3 at theta(LAB)=90 degrees using tagged photons in the energy range 14-31 MeV

The two-body photodisintegration of He-3 has been investigated using tagged photons with energies from 14-31 MeV at MAX-lab in Lund, Sweden. The two-body breakup channel was unambiguously identified by the (nonsimultaneous) detection of both protons and deuterons. This approach was made feasible by the overdetermined kinematic situation afforded by the tagged-photon technique. Proton-and deuteron-

Synchrotron photoemission study of (Zn,Co)O films with uniform Co distribution

We present results of a resonant photoemission study of (Zn,Co)O films with Co content between 2% and 7%. The films were grown by Atomic Layer Deposition (ALD) at low temperature of 160 degrees C and show fully paramagnetic behavior. The Co ions are uniformly distributed in the ZnO matrix and are free of foreign phases and metal accumulations as indicated by TEM data. The electronic structure of (

Ash Shutbah: A possible impact structure in Saudi Arabia

We have investigated the Ash Shutbah circular structure in central Saudi Arabia (21 degrees 37N 45 degrees 39E) using satellite imagery, field mapping, thin-section petrography, and X-ray diffraction of collected samples. The approximately 2.1km sized structure located in flat-lying Jurassic Tuwaiq Mountain Limestone has been nearly peneplained by erosional processes. Satellite and structural data

Optimal Inventory Policies when Purchase Price and Demand Are Stochastic

In this paper we consider the problem of a firm that faces a stochastic (Poisson) demand and must replenish from a market in which prices fluctuate, such as a commodity market. We describe the price evolution as a continuous stochastic process and we focus on commonly used processes suggested by the financial literature, such as the geometric Brownian motion and the Ornstein-Uhlenbeck process. It