1,614 research outputs found
Frictional Duality Observed during Nanoparticle Sliding
One of the most fundamental questions in tribology concerns the area
dependence of friction at the nanoscale. Here, experiments are presented where
the frictional resistance of nanoparticles is measured by pushing them with the
tip of an atomic force microscope. We find two coexisting frictional states:
While some particles show finite friction increasing linearly with the
interface areas of up to 310,000nm^2, other particles assume a state of
frictionless sliding. The results further suggest a link between the degree of
surface contamination and the occurrence of this duality.Comment: revised versio
Программные решения организации работы с ЭМК на мобильных устройствах в off-line режиме
The article deals with software solutions for e-health card under the access to the services of a medical information system. Consideration of some cross-platform solution for e-health card, as well as highlights the main approaches to the development of this service
ADE string vacua with discrete torsion
We complete the classification of (2,2) string vacua that can be constructed
by diagonal twists of tensor products of minimal models with ADE invariants.
Using the \LG\ framework, we compute all spectra from inequivalent models of
this type. The completeness of our results is only possible by systematically
avoiding the huge redundancies coming from permutation symmetries of tensor
products. We recover the results for (2,2) vacua of an extensive computation of
simple current invariants by Schellekens and Yankielowitz, and find 4
additional mirror pairs of spectra that were missed by their stochastic method.
For the model we observe a relation between redundant spectra and
groups that are related in a particular way.Comment: 13 pages (LaTeX), preprint CERN-TH.6931/93 and ITP-UH-20/93
(reference added
Ink transport modelling in Dip-Pen Nanolithography and Polymer Pen Lithography
Dip-pen nanolithography (DPN) and Polymer pen lithography (PPL) are powerful lithography techniques being able to pattern a wide range of inks. Transport and surface spreading depend on the ink physicochemical properties, defining its diffusive and fluid character. Structure assembly on surface arises from a balance between the entanglement of the ink itself and the interaction with the substrate. According to the transport characteristics, different models have been proposed. In this article we review the common types of inks employed for patterning, the particular physicochemical characteristics that make them flow following different dynamics as well as the corresponding transport mechanisms and models that describe them
Evangelische Bildung im Lebenslauf - ökonomisiert
Erwachsenenbildungsträger befinden sich nachgerade in einem Zustand der doppelten Ökonomisierung: von außen durch Nachfragetransformation und von innen durch Finanzierungszwang. Der Beitrag beschreibt die Entwicklung der zunehmenden Ökonomisierung von Bildung. Zunächst werden im Rahmen einer Subjekttheorie die entscheidenden ökonomischen und politischen Transformationen benannt. Im zweiten Schritt dann werden die praktischen Auswirkungen auf Einrichtungen nachgezeichnet - längst schon wirkt sich die Ökonomisierung auch auf das Angebotsspektrum Evangelischer Erwachsenenbildung aus. (DIPF/Orig.
Commentary CeNTech:nanotechnological research and application
The Centre for Nanotechnology (CeNTech), Münster, Germany, represents one of the first dedicated nanotechnology centres in Germany providing space and infrastructure for application, research and development in the area of nanotechnology. It offers an optimised environment for entrepreneurs to fur-ther develop their research ideas into marketable products as well as excellent conditions for application ori-ented research and further education. Three years after the opening of the CeNTech building most of the ex-pectations are fulfilled. The article describes the general aspects of the CeNTech concept and reviews its de-velopment in the first years
Taste, A New Incentive to Switch to (R)-Praziquantel in Schistosomiasis Treatment
Schistosomiasis, or Bilharzia, is a parasitic disease caused by flatworms, which affects about 200 million people worldwide. Praziquantel (PZQ) is the drug compound of choice in the control and treatment of this disease. Only half of the drug dose currently administered actually has activity against schistosomiasis, whereas the other half has no activity. Therefore, the WHO has assigned the low-cost preparation of the pure active component a key priority for future PZQ research and development. PZQ has two major administration drawbacks, the first being the high dose needed, the second its well documented bitter taste. Attempts of masking the unpleasant taste have not been successful. We hypothesized that the non-active component in PZQ would be the main contributor to the unpleasant taste of the drug. We determined the extent of bitterness for regular PZQ compared to the pure active component in a taste study in humans. We found that the pure active component alone is significantly less bitter than regular PZQ. This new finding should serve as an additional incentive for the PZQ research and development community to provide a low-cost, large-scale preparation route to the pure active component of PZQ
Serum Neopterin Is Not Increased in Obese Juveniles
Objective. Cardiovascular disease is associated with inflammation and immune activation, concentrations of immune activation markers like neopterin predict outcome in adults. Methods. Serum neopterin concentrations and early metabolic and pre-atherosclerotic symptoms were analyzed in 295 obese juveniles and 101 normal weight controls of similar age. Additionally, the influence of a 12 months weight reduction program on neopterin levels was investigated in 31 obese juveniles. Results. Intima-media thickness of common carotid arteries (IMT) and the concentrations of C-reactive protein (CRP) were increased in the obese juveniles (P < .001). Also triglycerides, oxidized LDL, fasted insulin levels, HOMA-index, leptin, liver transaminases and uric acid were increased compared to the controls. However, serum neopterin was decreased in the obese versus non-obese juveniles (P < .03). The intervention consisting of regular sports, nutritional devices, and a psychologic attendance led after 12 months to an increase of neopterin concentration (P < .05; paired test). Conclusions. Neopterin concentrations in juvenile obesity behaved considerably different from what was demonstrated in adults, levels did not correlate with metabolic and pre-atherosclerotic symptoms found in early phases although early vascular burden and chronic low grade inflammation was indicated by increased IMT and CRP. Neopterin concentrations increased after a 12 months intervention program
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