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Nonlinear electrical properties of Si three-terminal junction devices

This letter reports on the realization and characterization of silicon three-terminal junction devices made in a silicon-on-insulator wafer. Room temperature electrical measurements show that the fabricated devices exhibit pronounced nonlinear electrical properties inherent to ballistic electron transport in a three-terminal ballistic junction (TBJ) device. The results show that room temperature f

Nanoparticle-based capillary electroseparation of proteins in polymer capillaries under physiological conditions.

Totally porous lipid-based liquid crystalline nanoparticles were used as pseudostationary phase for capillary electroseparation with LIF detection of proteins at physiological conditions using unmodified cyclic olefin copolymer capillaries (Topas, 6.7 cm effective length). In the absence of nanoparticles, i.e. in CE mode, the protein samples adsorbed completely to the capillary walls and could not

Hard sphere-like glass transition in eye lens α-crystallin solutions.

We study the equilibrium liquid structure and dynamics of dilute and concentrated bovine eye lens α-crystallin solutions, using small-angle X-ray scattering, static and dynamic light scattering, viscometry, molecular dynamics simulations, and mode-coupling theory. We find that a polydisperse Percus-Yevick hard-sphere liquid-structure model accurately reproduces both static light scattering data an

Lawyers in Venture Capital Contracting: Theory and Evidence

Real-world financial contracts are sometimes so complex that it can be difficult to understand their exact payoff consequences. We develop and test a theoretical model of a venture capitalist (VC) negotiating with an entrepreneur who may overweigh or underweigh the payoff consequences of contractual downside protection (DP). A lawyer with expertise in venture capital can inform the entrepreneur ab

Serum levels of vitamin D, PTH, calcium and breast cancer risk - a prospective nested case-control study.

Previous studies indicate that calcium and its regulating hormones, i.e. parathyroid hormone (PTH) and vitamin D, might affect breast cancer risk. Evidence also suggests that this relationship could be influenced by menopausal status and BMI. We examined breast cancer risk related to pre-diagnostic serum levels of vitamin D (25OHD(2) and 25OHD(3)), PTH and calcium using a nested case-control desig

Generic Ising Trees

The Ising model on a class of infinite random trees is defined as a thermodynamic limit of finite systems. A detailed description of the corresponding distribution of infinite spin configurations is given. As an application, we study the magnetization properties of such systems and prove that they exhibit no spontaneous magnetization. Furthermore, the values of the Hausdorff and spectral dimension

Aminooxy analog of histamine is an efficient inhibitor of mammalian l-histidine decarboxylase: combined in silico and experimental evidence

Histamine plays highlighted roles in the development of many common, emergent and rare diseases. In mammals, histamine is formed by decarboxylation of l-histidine, which is catalyzed by pyridoxal-5'-phosphate (PLP) dependent histidine decarboxylase (HDC, EC 4.1.1.22). The limited availability and stability of the protein have delayed the characterization of its structure-function relationships. Ou

Flying with the winds: differential migration strategies in relation to winds in moth and songbirds.

The gamma Y moth selects to migrate in stronger winds compared to songbirds, enabling fast transport to distant breeding sites, but a lower precision in orientation as the moth allows itself to be drifted by the winds. Photo: Ian Woiwod. In Focus: Chapman, J.R., Nilsson, C., Lim, K.S., Bäckman, J., Reynolds, D.R. & Alerstam, T. (2015) Adaptive strategies in nocturnally migrating insects and so

Altitudinal divergence in maternal thermoregulatory behaviour may be driven by differences in selection on offspring survival in a viviparous lizard

Plastic responses to temperature during embryonic development are common in ectotherms, but their evolutionary relevance is poorly understood. Using a combination of field and laboratory approaches, we demonstrate altitudinal divergence in the strength of effects of maternal thermal opportunity on offspring birth date and body mass in a live-bearing lizard (Niveoscincus ocellatus). Poor thermal op

A Reversible Nanoconfined Chemical Reaction

Hydrogen is recognized as a potential, extremely interesting energy carrier system, which can facilitate efficient utilization of unevenly distributed renewable energy. A major challenge in a future "hydrogen economy" is the development of a safe, compact, robust, and efficient means of hydrogen storage, in particular, for mobile applications. Here we report on a new concept for hydrogen storage u

Competitive binding-based optical DNA mapping for fast identification of bacteria - multi-ligand transfer matrix theory and experimental applications on Escherichia coli.

We demonstrate a single DNA molecule optical mapping assay able to resolve a specific Escherichia coli strain from other strains. The assay is based on competitive binding of the fluorescent dye YOYO-1 and the AT-specific antibiotic netropsin. The optical map is visualized by stretching the DNA molecules in nanofluidic channels. We optimize the experimental conditions to obtain reproducible barcod

Pretreatment: The key to efficient utilization of lignocellulosic materials

Second-generation ethanol production from various lignocellulosic materials based on enzymatic hydrolysis of cellulose has moved from research in lab scale to pilot- and demo scale but has not yet reached commercial scale. One of the crucial process steps is the pretreatment of the biomass, which has as primary aim to make the biomass accessible to enzymatic attack, as it has a large impact on all

On Distributed Knowledge Bases for Robotized Small-Batch Assembly

The flexibility demands in manufacturing are severe, e.g., for rapid-change-over to new product variants, while robots are flexible machines that potentially can be adapted to a large variety of production tasks. Task definitions such as explicit robot programs are hardly reusable from an application point-of-view. To improve the situation, a knowledge-based approach exploiting distributed declara

Increase of club cell (Clara) protein (CC16) in plasma and urine after exercise challenge in asthmatics and healthy controls, and correlations to exhaled breath temperature and exhaled nitric oxide.

Exercise is known to affect the airway epithelium through dehydration, followed by a release of mediators, such as club cell (Clara) protein (CC16). The aim of this study was to follow the CC16 levels at repeated time points in plasma and urine after exercise in asthmatic subjects and controls, and to relate the findings to exhaled breath temperature (EBT) and exhaled nitric oxide (NO). Twenty-two

Serial monitoring of circulating tumor DNA in patients with primary breast cancer for detection of occult metastatic disease.

Metastatic breast cancer is usually diagnosed after becoming symptomatic, at which point it is rarely curable. Cell-free circulating tumor DNA (ctDNA) contains tumor-specific chromosomal rearrangements that may be interrogated in blood plasma. We evaluated serial monitoring of ctDNA for earlier detection of metastasis in a retrospective study of 20 patients diagnosed with primary breast cancer and

Trees tracking a warmer climate: The Holocene range shift of hazel (Corylus avellana) in northern Europe

Palaeoecological records provide a rich source of information to explore how plant distribution ranges respond to climate changes, but their use is complicated by the fact that, especially when based on pollen data, they are often spatially too inaccurate to reliably determine past range limits. To solve this problem, we focus on hazel (Corylus avellana), a tree species with large and heavy fruits

Icosahedral capsid formation by capsomers and short polyions.

Kinetical and structural aspects of the capsomer-polyion co-assembly into icosahedral viruses have been simulated by molecular dynamics using a coarse-grained model comprising cationic capsomers and short anionic polyions. Conditions were found at which the presence of polyions of a minimum length was necessary for capsomer formation. The largest yield of correctly formed capsids was obtained at w