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Nanowire-based multiple quantum dot memory

The authors propose and demonstrate an alternative memory concept in which a storage island is connected to a nanowire containing a stack of nine InAs quantum dots, each separated by thin InP tunnel barriers. Transport through the quantum dot structure is suppressed for a particular biasing window due to misalignment of the energy levels. This leads to hysteresis in the charging/discharging of the

Distribution and diel migration of macroinvertebrates within dense submerged vegetation

1. We studied vertical and horizontal distribution of macroinvertebrates within a dense stand of Chara spp. in Lake Krankesjon, southern Sweden. Invertebrates were sampled at three depths within the vegetation and at three distances from the vegetation edge during day and night in July and August. Corresponding samples of oxygen content of the water were taken. 2. The densities (number of inverteb

Perilipin A is essential for the translocation of hormone-sensitive lipase during lipolytic activation

A key step in lipolytic activation of adipocytes is the translocation of hormone-sensitive lipase (HSL) from the cytosol to the surface of the lipid storage droplet. Adipocytes from perilipin-null animals have an elevated basal rate of lipolysis compared with adipocytes from Wild-type mice, but fail to respond maximally to lipolytic stimuli. This defect is downstream of the p-adrenergic receptor-a

Cytogenetic and molecular genetic evolution of chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is genetically characterized by the presence of the reciprocal translocation t(9;22)(q34;q11), resulting in a BCR/ABL gene fusion on the derivative chromosome 22 called the Philadelphia (Ph) chromosome. In 2-10% of the cases, this chimeric gene is generated by variant rearrangements, involving 9q34, 22q11, and one or several other genomic regions. All chromosomes hav

Comparison of different extraction techniques for isolation of antioxidants from sweet grass (Hierochloe odorata)

Strong antioxidants, 5,8-dihydroxycoumarin and 5-hydroxy-8-O-beta-D-glucopyranosyl-benzopyranone were extracted from sweet grass (Hierochloe odorata L.) by using Soxhlet (SE), microwave-assisted (MAE) and supercritical fluid carbon dioxide (SFE) extractions at different extraction schemes and parameters. One-step MAE gave the most concentrated extract with 8.15% of 5,8-dihydroxycoumarin (extract y

Introduction of human papillomavirus (HPV) vaccination in Sweden

The Swedish National Board of Health and Welfare (NBH) decided that a vaccine that protects against cervical cancer caused by human papillomavirus (HPV) should be included in the childhood vaccination directive as a nationwide-programme targeting 12-yearold girls from 2010 as a part of the school-health programme. Currently, vaccination of girls 13-18 years of age is covered by the public insuranc

An amperometric biosensor based on laccase immobilized in polymer matrices for determining phenolic compounds

An amperometric enzyme electrode based on laccase for determining phenolic compounds is proposed. The following three types of polymer materials were used for enzyme immobilization on the surface of a glassy-carbon electrode: positively charged cetyl ethyl poly (ethyleneimine) (CEPEI) and negatively charged commercial Nafion and Eastman AQ 29D polymers. The advantages and disadvantages of each of

Short-range structure of proton-conducting perovskite BaInxZr1-xO3-x/2 (x=0-0.75)

In a systematic study, we investigate the effect of dopant level and hydration on the short-range structure of the proton-conducting perovskite-type oxide BaInxZr1-xO3-x/2 (x = 0 - 0.75), using infrared and Raman spectroscopy. The results show that the doping leads to significant local distortions of the average cubic structure of these materials. By increasing the In concentration from x = 0 to x

Capturing ion exchanger-bound infectious pancreatic necrosis virus - design and application for large volume water samples

A method was designed for rapid and reliable demonstration of the presence of infectious pancreatic necrosis virus retrieved from 5 1 water samples. Viruses together with an added carrier protein were adsorbed to a resin of an added anion exchanger. Then the resin was collected rapidly and quantitatively through a specific device which we designed. The resin was transferred to a column from which

Magnetic CLEAR supports for solid-phase synthesis of peptides and small organic molecules

Paramagnetic versions of the CLEAR supports were prepared by entrapment of magnetite particles during suspension polymerization of allylamine, trimethylolpropane ethoxylate (14/3 EO/OH) triacrylate, and trimethylolpropane trimethacrylate. Swelling studies in a broad range of solvents showed comparable swelling of magnetic beads and regular CLEAR beads. The application of the magnetic beads as the

Quantification of Membrane Proteins Using Nonspecific Protease Digestions

We present a mass spectrometry-based method for the identification and quantification of membrane proteins using the low-specificity protease Proteinase K, at very high pH, to digest proteins isolated by a modified SDS-PAGE protocol. The resulting peptides are modified with a fragmentation-directing isotope labeled tag. We apply the method to quantify differences in membrane protein expression of

Fuel use and metabolic response to endurance exercise: a wind tunnel study of a long-distance migrant shorebird

This study examines fuel use and metabolism in a group of long-distance migrating birds, red knots Calidris canutus (Scolopacidae), flying under controlled conditions in a wind tunnel for up to 10 h. Data are compared with values for resting birds fasting for the same time. Plasma levels of free fatty acids, glycerol and uric acid were elevated during flight, irrespective of flight duration (1-10h

Fracture mechanics analysis of microcracks in thermally cycled thermal barrier coatings

The effects from thermal shock loading on pre-existing microcracks within thermal barrier coatings (TBCs) have been investigated through a finite element based fracture mechanical analysis. The TBC system consists of a metallic bond coat and a ceramic top coat. The rough interface between the top and bond coats holds an alumina oxide layer. Stress concentrations at the interface due to the interfa

More pronounced salt dependence and higher reactivity for platination of the hairpin r(CGCGUUGUUCGCG) compared with d(CGCGTTGTTCGCG)

The DNA interference pathways exhibited by cisplatin and related anticancer active metal complexes have been extensively studied. Much less is known to what extent RNA interaction pathways may operate in parallel, and perhaps contribute to both antineoplastic activity and toxicity. The present study was designed with the aim of comparing the reactivity of two model systems comprising RNA and DNA h

Allergen-induced eosinophil cytolysis is a primary mechanism for granule protein release in human upper airways

Cytotoxic eosinophil granule proteins are considered important in the pathogenesis of allergic airway diseases such as rhinitis and asthma. To explore the cellular mechanisms behind eosinophil granule release in human allergic airways, 16 symptom-free patients with seasonal allergic rhinitis were challenged daily with allergen during 1 wk. Nasal lavage samples and biopsies, obtained before and 24

N-terminal domain linkage modulates the folding properties of protein S epidermal growth factor-like modules

Protein S interacts with activated protein C to play a crucial role in blood anticoagulation, and protein S deficiency is associated with increased risk of thrombosis. Despite the large volume of functional data available for this protein, no atomic resolution structure data have yet been reported. This is due at least in part to difficulties encountered when trying to produce fragments dissected

Measurement of helicity-dependent photoabsorption cross sections on the neutron from 815 to 1825 MeV

Helicity-dependent total photoabsorption cross sections on the deuteron have been measured for the first time at ELSA (Bonn) in the photon energy range from 815 to 1825 MeV. Circularly polarized tagged photons impinging on a longitudinally polarized LiD target have been used together with a highly efficient 4 pi detector system. The data around 1 GeV are not compatible with predictions from existi