On oscillatorlike Hamiltonians and squeezing

Generalizing a recent proposal leading to one-parameter families of Hamiltonians and to new sets of squeezed states, we construct larger classes of physically admissible Hamiltonians permitting new developments in squeezing. Coherence is also discussed.Comment: 15 pages, Late

Biodegradable, lignin-based encapsulation enables delivery of Trichoderma reesei with programmed enzymatic release against grapevine trunk diseases

Antagonistic fungi such as Trichoderma reesei are promising alternatives to conventional fungicides in agriculture. This is especially true for worldwide occurring grapevine trunk diseases, causing losses of US$1.5 billion every year, at which conventional fungicides are mostly ineffective or prohibited by law. Yet, applications of Trichoderma against grapevine trunk diseases are limited to preventive measures, suffer from poor shelf life, or uncontrolled germination. Therefore, we developed a mild and spore-compatible layer-by-layer assembly to encapsulate spores of a new mycoparasitic strain of T. reesei IBWF 034-05 in a bio-based and biodegradable lignin shell. The encapsulation inhibits undesired premature germination and enables the application as an aqueous dispersion via trunk injection. First injected into a plant, the spores remain in a resting state. Second, when lignin-degrading fungi infect the plant, enzymatic degradation of the shell occurs and germination is selectively triggered by the pathogenic fungi itself, which was proven in vitro. Germinated Trichoderma antagonizes the fungal pathogens and finally supplants them from the plant. This concept enables Trichoderma spores for curative treatment of esca, one of the most infective grapevine trunk diseases worldwide

Corrosion studies of different ferrous alloys for rolling cylinders

peer reviewedThe aim of this work is to study the corrosion behaviour in chloride media of a high chromium iron alloy. The influence of the surface finishing as well as the heat treatment was analysed. The technique employed for measuring the corrosion behaviour was the Electrochemical Impedance Spectroscopy, an electrochemical technique that allows the observation not only of the corrosion rates but also the changes on the corrosion mechanism of the alloy. The results showed that it is worth performing a double tempering and a having smoother surface finishing only for long exposure periods. A comparison between different oxidising conditions was also performed simulating the life in service of the hot rolling cylinders and revealed an increase in the protective properties as the oxidising time increased due to the chromium present on the alloy (18%). (c) 2005 Elsevier Ltd. All rights reserved

Spectropolarimetric observations of Herbig Ae/Be Stars I: HiVIS spectropolarimetric calibration and reduction techniques

Using the HiVIS spectropolarimeter built for the Haleakala 3.7m AEOS telescope in Hawaii, we are collecting a large number of high precision spectropolarimetrc observations of stars. In order to precisely measure very small polarization changes, we have performed a number of polarization calibration techniques on the AEOS telescope and HiVIS spectrograph. We have extended our dedicated IDL reduction package and have performed some hardware upgrades to the instrument. We have also used the ESPaDOnS spectropolarimeter on CFHT to verify the HiVIS results with back-to-back observations of MWC 361 and HD163296. Comparision of this and other HiVIS data with stellar observations from the ISIS and WW spectropolarimeters in the literature further shows the usefulness of this instrument.Comment: 35 pages, 44 figures, Accepted by PAS

Solar Physics - Plasma Physics Workshop

A summary of the proceedings of a conference whose purpose was to explore plasma physics problems which arise in the study of solar physics is provided. Sessions were concerned with specific questions including the following: (1) whether the solar plasma is thermal or non-themal; (2) what spectroscopic data is required; (3) what types of magnetic field structures exist; (4) whether magnetohydrodynamic instabilities occur; (5) whether resistive or non-magnetohydrodynamic instabilities occur; (6) what mechanisms of particle acceleration have been proposed; and (7) what information is available concerning shock waves. Very few questions were answered categorically but, for each question, there was discussion concerning the observational evidence, theoretical analyses, and existing or potential laboratory and numerical experiments

Comment on ``the Klein-Gordon Oscillator''

The different ways of description of the $S=0$ particle with oscillator-like interaction are considered. The results are in conformity with the previous paper of S. Bruce and P. Minning.Comment: LaTeX file, 5p

Pregnancy associated glyciprotein and progesterone concentrations in plasma of sheep during gestation and post-partum period

Contributed to: 109th meeting of the British Society of Animal Production (Scarborough, UK, Mar 21-23, 1994).Peer reviewe

On realizations of nonlinear Lie algebras by differential operators

We study realizations of polynomial deformations of the sl(2,R)- Lie algebra in terms of differential operators strongly related to bosonic operators. We also distinguish their finite- and infinite-dimensional representations. The linear, quadratic and cubic cases are explicitly visited but the method works for arbitrary degrees in the polynomial functions. Multi-boson Hamiltonians are studied in the context of these ``nonlinear'' Lie algebras and some examples dealing with quantum optics are pointed out.Comment: 21 pages, Latex; New examples added in Sect.

Einfluss unterschiedlicher Biochars auf die Mobilisierung von Methyl-, Ethyl- und Gesamtquecksilber aus einem kontaminierten Auenboden unter variierenden Redoxbedingungen

Die Auenböden der Wupper weisen durch die metallverarbeitende, die chemische und die Textilindustrie, sowie den Einsatz von Fungiziden zum Teil sehr hohe Quecksilberkonzentrationen auf. Quecksilber (Hg) ist hoch toxisch, wobei seine Toxizität durch die Methylierung noch einmal deutlich verstärkt wird. Die Methylierung erfolgt hierbei vor allem unter anaeroben Bedingungen durch sulfatreduzierende Bakterien. In Auenböden stellen sich aufgrund regelmäßiger Überflutungen häufig anaerobe Bedingungen ein. Dies erhöht das Risiko der Quecksilbermethylierung und des Austrags von Methylquecksilber (MeHg) in die Wupper, wo dieses in Fischen angereichert werden kann. Biochar wird als Bodenzuschlagsstoff zur Verringerung der Mobilisierung von vielen Schwermetallen empfohlen (In-situ-Sanierung). Jedoch ist die Auswirkung von Biochars auf das Mobilisierungsverhalten von Hg, MeHg und Ethylquecksilber (EtHg) unter kontrollierten Redoxbedingungen kaum erforscht. Daher war es das Ziel, das Mobilisierungsverhalten von Hg, MeHg und EtHg in einem kontaminierten Auenboden der Wupper unter variierenden Redoxbedingungen im Labor zu quantifizieren, steuernde Prozesse zu identifizieren und den Einfluss zweier unterschiedlicher Biochars zu prüfen. Die Biochars basierten auf Kiefernzapfen und wurden bei Pyrolysetemperaturen von 200 und 500°C hergestellt. Unter Verwendung technisch ausgereifter biogeochemischer Mikrokosmen, wurden Überflutungssituationen simuliert, wobei das Redoxpotential (EH) gezielt gesteuert wurde. Die Probenahmen erfolgten bei definierten EH Werten, wobei neben Hg, MeHg und EtHg weitere Parameter analysiert wurden, die die Freisetzung und Bildung bestimmter Quecksilberformen beeinträchtigen. Die Freisetzung von Hg war unter niedrigem EH (≤ 0 mV) besonders ausgeprägt, während die höchsten MeHg-Konzentrationen bei einem EH von 100 mV gemessen wurden. Die höchsten EtHg-Konzentrationen fanden sich bei einem EH von 0 mV. Die Zugabe der Biochars zeigte nur geringfügige Auswirkungen auf die Freisetzung und Methylierung von Hg