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An investigation of the reaction mechanism for the promotion of propane oxidation over Pt/Al2O3 by SO2

Total oxidation of propane with oxygen in the absence and the respective presence of SO2 in the feed gas was studied over 1 wt% Pt on gamma -Al2O3 using transient experiments with TAP (temporal analysis of products) and in situ DRIFT spectroscopy. The TAP experiments confirm the promoting role of SO2 on the conversion of propane and, moreover, show an inhibiting effect from SO2 on the conversion o

Changes in pore morphology and fluid transport in compressed articular cartilage and the implications for joint lubrication

Cartilage sections were cut from the middle zone of pig knee articular cartilage and attached to substrates in two different kinds of newly designed 'pressure cells', one for fluorescence the other for NMR measurements, The fluorescence cell was filled with buffer solution containing fluorescently marked 70 kDa dextran which was allowed to diffuse into the cartilage pores. A second glass surface w

Enhanced expression of iNOS intratumorally and at the immunization site after immunization with IFNgamma-secreting rat glioma cells

Nitric oxide (NO) can modulate both tumor growth and antitumor immune responses. In order to elucidate the mechanism of curative therapeutic immunization with IFNgamma-producing glioma cells, we examined the expression of inducible nitric oxide synthase (iNOS) in tissue sections from immunized animals. There was a significantly enhanced iNOS expression both intratumorally and at the immunization s

A uniqueness theorem in the inverse spectral theory of a certain higher-order ordinary differential equation using Paley-Wiener methods

The paper examines a higher-order ordinary differential equation of the form P[u]:= Sigma(j,k=0)(m) D(j)a(jk)D(k)u = gimel u, x is an element of [0, b), where D=i(d/dx), and where the coefficients a(jk), j, k is an element of [0,M], with a = 1, satisfy certain regularity conditions and are chosen so that the matrix (a(jk)) is hermitean. It is also assumed that m > 1. More precisely, it is proved,

An Integrated Model of the European Extremely Large Telescope

Integrated models including optics, structures, control systems, and disturbances are important design tools for Extremely Large Telescopes (ELTs). An integrated model has keen formulated for the European ELT and it includes telescope structure, main servos, primary mirror segment control system, wind, optics, wavefront sensor, deformable mirror, and an AO reconstructor and controller. There are t

Assembling ferromagnetic single-electron transistors by atomic force microscopy

We demonstrate the assembly of nanoscale ferromagnetic single-electron transistors using atomic force microscopy for imaging as well as for nanoscale manipulation. A single 30 nm Au disc, forming the central island of the transistor, is manipulated with angstrom precision into the gap between a plasma-oxidized Ni source and drain electrodes. The tunnel resistances can be tuned in real time during

Improvement of the detection of myocardial ischemia thanks to information technologies

Background: The standard 12-lead ECG remains one of the basic investigations for the early detection and assessment of acute coronary syndromes. It is easy to perform, anywhere and anytime, and can be digitally transmitted within minutes to an emergency medical service for remote advice and triage. But the conventional ST-segment deviation criteria are of limited diagnostic accuracy. The purpose o

IL-1 beta induces murine airway 5-HT2A receptor hyperresponsiveness via a non-transcriptional MAPK-dependent mechanism

Background: Interleukin 1 beta ( IL- I beta) is found in bronchoalveolar lavage fluids from asthmatic patients and plays an important role in normal immunoregulatory processes but also in pathophysiological inflammatory responses. The present study was designed to investigate if IL- I beta could be involved in the development of airway hyperresponsiveness and if transcriptional mechanisms, epithel

Marker-based relatedness predicts egg-hatching failure in great reed warblers

I examine the relationship between reproductive success and marker-based relatedness (MBR; inferred from variation at 21 microsatellite loci) of pair-mates in a semi-isolated population of great reed warblers (Acrocephalus arundinaceus) over a 12 year period. There was a negative relationship between egg-hatching success and MBR, but no association between MBR and three other components of fitness

Effect of graded testicular doses of radiotherapy in patients treated for carcinoma-in-situ in the testis

PURPOSE: To determine the effect of radiotherapy in doses 14 to 20 Gy on eradication of carcinoma-in-situ (CIS) testis and on the Leydig cell function. PATIENTS AND METHODS: Forty-eight patients presented with unilateral testicular germ cell cancer and CIS of the contralateral testis. The CIS-bearing testis was treated with daily irradiation doses of 2 Gy, 5 days a week, to a cumulative dose of 20

An approach for on-line cutting edge stress estimation

Cutting edge deteriorations are attributed to higher mechanical and thermal stresses working on it during metal cutting. However, the stress estimation is a difficult task, especially when on-line estimation is desired. This paper presents a new approach for cutting edge mechanical stress estimation and load simulation. The approach can be applied in the implementation of on-line stress estimation

Stabilization of internal charges in a protein: Water penetration or conformational change?

The ionizable amino acid side chains of proteins are usually located at the surface. However, in some proteins an ionizable group is embedded in an apolar internal region. Such buried ionizable groups destabilize the protein and may trigger conformational changes in response to pH variations. Because of the prohibitive energetic cost of transferring a charged group from water to an apolar medium,

Comparison of overlap-based models for approximating the exchange-repulsion energy

Different ways of approximating the exchange-repulsion energy with a classical potential function have been investigated by fitting various expressions to the exact exchange-repulsion energy for a large set of molecular dimers. The expressions involve either the orbital overlap or the electron-density overlap. For comparison, the parameter-free exchange-repulsion model of the effective fragment po