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We report on a novel, noninvasive method applying Thomson scattering to measure the evolution of the electron beam energy inside a laser-plasma accelerator with high spatial resolution. The determination of the local electron energy enabled the in-situ detection of the acting acceleration fields without altering the final beam state. In this Letter we demonstrate that the accelerating fields evolve from (265±119) GV/m to (9±4) GV/m in a plasma density ramp. The presented data show excellent agreement with particle-in-cell simulations. This method provides new possibilities for detecting the dynamics of plasma-based accelerators and their optimization.

The performance of future ultra-long haul communication systems exploiting phase-encoded signals is likely to be compromised by noise generated during signal transmission. One potential way to mitigate such noise is to use Phase Sensitive Amplifiers (PSAs) which have been demonstrated to help remove phase as well as amplitude noise from phase-encoded signals. Recently, we showed that a PSA-based signal regenerator based on degenerate four-wave mixing can be implemented in a network-compatible manner in which only the (noisy) signal is present at the device input (black-box operation). The developed regenerator was also able to perform simultaneous wavelength conversion and multicasting, details/analysis of which are presented herein. However, this scheme was tested only with artificial noise generated in the laboratory and with the regenerator placed in front of the receiver, rather than in-line where even greater performance benefits are to be expected. Here, we address both theoretically and experimentally the important issue of how such a regenerator, operating for convenience in a multicasting mode, performs as an in-line device in an installed transmission fiber link. We also investigate the dispersion tolerance of the approach. © 2006 IEEE.

The controlled imaging and transport of ultra‐relativistic electrons from laser‐plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak‐brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV‐photon flux. In addition, first experimental findings of utilizing cavity‐based monitors for non‐invasive beam‐position measurements in a noisy electromagnetic laser‐plasma environment are discussed.

A laser plasma accelerator is under development at the Max‐Planck‐Institut fur Quantenoptik in Garching. This accelerator will be part of an X‐ray table top FEL in the future. The FEL radiation will be produced with a small period in‐vacuum undulator. The coercivity of the magnetic material has to be sufficiently high in order to avoid demagnetization due to electron losses. The best performance can be achieved with a cryogenic permanent magnet undulator design. (Nd0.2Pr0.8)2Fe14B magnets are suited for low temperatures since they do not suffer from a spin reorientation. A new (Nd0.2Pr0.8)2Fe14B material has been characterized at various temperatures and the results are presented. Based on this material a 20 period prototype with a period length of 9 mm and a magnetic gap of 2.5 mm is currently under construction.

The design and current status of experiments to couple the Tapered Hybrid Undulator (THUNDER) to the Lawrence Berkeley National Laboratory (LBNL) laser plasma accelerator (LPA) to measure electron beam energy spread and emittance are presented.

Latest developments in the field of laser-wakefield accelerators (LWFAs) have led to relatively stable electron beams in terms of peak energy, charge, pointing and divergence from mmsized accelerators. Simulations and LWFA theory indicate that these beams have low transverse emittances and ultrashort bunch durations on the order of ∼ 10 fs. These features make LWFAs perfectly suitable for driving high-brightness X-ray undulator sources and free-electron lasers (FELs) on a university-laboratory scale.With the detection of soft-X-ray radiation from an undulator source driven by laser-wakefield accelerated electrons, we succeeded in achieving a first milestone on this path. The source delivers remarkably stable photon beams which is mainly due to the stable electron beam and our miniature magnetic quadrupole lenses, which significantly reduce its divergence and angular shot-to-shot variation. An increase in electron energy allows for compact, tunable, hard-Xray undulator sources. Improvements of the electron beams in terms of charge and energy spread will put table-top FELs within reach. © 2010 American Institute of Physids.

A design of a compact free‐electron laser (FEL), generating ultra‐fast, high‐peak flux, XUV pulses is presented. The FEL is driven by a high‐current, 0.5 GeV electron beam from the Lawrence Berkeley National Laboratory (LBNL) laser‐plasma accelerator, whose active acceleration length is only a few centimeters. The proposed ultra‐fast source (∼10 fs) would be intrinsically temporally synchronized to the drive laser pulse, enabling pump‐probe studies in ultra‐fast science. Owing to the high current (≳10 kA) of the laser‐plasma‐accelerated electron beams, saturated output fluxes are potentially greater than 1013 photons/pulse. Devices based both on self‐amplified spontaneous emission and high‐harmonic generated input seeds, to reduce undulator length and fluctuations, are considered.

Quasi-monoenergetic, laser-driven electron beams of up to ∼ 200 MeV in energy have been generated from steady-state-flow gas cells [1], These beams are emitted within a low-divergence cone of 2.1 ± 0.5 mrad FWHM and feature unparalleled shot-to-shot stability in energy (2.5% rms), pointing direction (1.4 mrad rms) and charge (16% rms) owing to a highly reproducible plasma-density profile within the laser-plasma-interaction volume. Laser-wakefield acceleration (LWFA) in gas cells of this type constitutes a simple and reliable source of relativistic electrons with well defined properties, which should allow for applications such as the production of extreme-ultraviolet undulator radiation in the near future. © 2009 American Institute of Physics.

The literature on lithium treatment during chronic dialysis is reviewed and a new case presented. In a patient suffering from bipolar affective disorder, onset of hemodialysis precipitated a manic episode. Oral lithium, given in single postdialysis doses, was well-tolerated, effective, and easy to handle. During 19 months of constant dosing, 10.8 mEq after each dialysis maintained steady-state predialysis levels at 0.50-0.77 mEq/L. Steady-state levels of the published cases were plotted against the maintenance doses and the regression function through the origin was calculated. From this, it is concluded that the average maintenance dose (in mEq), which is 18 times the desired predialysis level (in mEq/L), might serve as a starting dose, provided predialysis levels are closely monitored and doses readjusted accordingly. Preliminary evidence suggests that one to two weeks of constant dosing are needed to achieve steady-state, but that months or even years are required to fully assess the long-term fluctuations in lithium levels.

Das Kernproblem bei der Diagnose der Sucht liegt anders als in der ubrigen Medizin darin, das viele dieser Patienten nicht uber ihre Symptome klagen, sondern sie im Gegenteil nicht wahrhaben wollen. Deshalb haben diagnostische Verfahren, die von der Mitarbeit des Patienten unabhangig sind, hier einen hohen Stellenwert. Beim chronischen Alkoholismus ist dies in erster Linie die Bestimmung der γ-Glutamyltransferase (GGT), des mittleren korpuskularen Erythrozytenvolumens (MCV) und des Carbohydrate Deficient Transferrins (CDT). Die Sensitivitat dieser Parameter liegt bei 70–90%, ihre Spezifitat liegt im Falle des GGT und des MCV bei 70% und im Falle des CDT bei uber 90% (5). Falsch-positive Befunde treten bei der GGT relativ haufig durch cholestatische Lebererkrankungen und die Behandlung mit Enzyminduktoren wie Carbamazepin auf. MCV wird durch nicht-alkoholische Lebererkrankungen, Vitamin-B12- und Folsauremangel erhoht (Ubersicht in 3). Falsch-positive CDT-Werte sind auserst selten und kommen fast ausschlieslich bei schweren Lebererkrankungen wie biliarer Zirrhose, chronisch aktiver Hepatitis und dekompensierter Leberzirrhose, bei genetischen Transferrin-D-Varianten und beim CDG-Syndrom (Carbohydrate Deficient Glycoprotein Syndrome) vor (Ubersicht in 2). Falsch-negative Befunde sind dagegen haufiger (1, 2, 3, 16). Disulfiram (Antabus®), welches wir oft einsetzen (s.u.), beeinflust CDT nicht (9). Die Zeit bis zur Erhohung bzw. bis zur Normalisierung von GGT, MCV und CDT bei Beginn bzw. nach dem Ende des regelmasigen Alkoholgebrauchs betragt fur GGT und CDT mehrere Wochen und fur MCV (wegen der langen Erythrozytenuberlebensdauer) mehrere Monate.

In a review of the literature it is shown that most HIV-infected patients experience psychoreactive disorders early in the course of the disease and psycho-organic disorders at its more advanced stages. The latter are due either to the HIV itself or to opportunistic infections and malignancies. Differential diagnoses comprise adverse-effects of chemotherapeutics or illicit drugs and, in addition, independent psychiatric disorders certains of which may be over-represented in high-risk groups. Diagnostic and therapeutic strategies are reviewed.

Due to the strong electrostatic repulsion of Polystyrene latexes in water, these systems show shortrrange liquid-like order at low concentrations and long range, crystalline order at higher concentrations. Both phases were investigated by photon correlation spectroscopy. The first dynamic light scattering experiments on single crystals are reported. The dynamics of the colloidal liquids may be described by two diffusion coefficients for short and long times.

The short and long-time diffusion coefficient in suspensions of charged polystryrene spheres was determined by photon correlation spectroscopy over a wide range of concentrations and k-vectors. The results indicate, that the long time diffusion of interacting Brownian particles may be described by the static structure factor which gives the concentration dependence and a reduced memory function M′(k,ω=0) which is independent of the concentration and describes the dynamical aspects of the repulsive interaction potential.

Mechanisierung der Arbeit bedeutet, das das jedesmalige Nachdenken daruber, wie eine Arbeit erledigt werden soll, ausgeschaltet wird.

Es ist eine grose Zahl von Buchungsmaschinen auf dem Markte. Jede soll die beste sein. So sagen die Verkaufer.

Die Anordnung der Konti in Karten- oder Loseblattform gibt die Moglichkeit ihrer beliebigen Ordnung. Die Durchbildung solcher Ordnungssysteme hatte keine Bedeutung, solange man mit gebundenen Buchern arbeitete. Dort war es ja kaum moglich, eine bestimmte Ordnung dauernd einzuhalten, und sobald man mit Ubertragungen auf eine andere Seite beginnen muste, wurde die richtige Aufeinanderfolge schon unterbrochen.

Man kann bei Buchungsmaschinen nur unter Vorbehalt von Leistungen sprechen. Selbst und allein leisten sie nichts. Sie sind nur geeignet, die Leistungsfahigkeit eines Menschen zu steigern.

Auch die besten Buchhaltungsmaschinen werden zusammen mit den vorteilhaftest entworfenen Formularen nicht den richtigen Nutzeffekt ergeben, wenn nicht der ganze Buchhaltungsbetrieb in bezug auf Zusammenarbeit in der richtigen Weise eingestellt ist. Hierher gehort die Ausbildung der Arbeitskrafte, die Begrenzung und Feststellung der Verantwortlichkeit, die Einrichtung der notwendigen Kontrollen und die Aufstellung einer genauen Arbeitsordnung, die es einem jeden Mitarbeiter ermoglicht, zu verstehen, wie seine eigene Arbeit mit der seiner Mitarbeiter zusammenhangt.

Nachdem nunmehr alles besprochen ist, was auf die Organisation der maschinellen Buchhaltung Einflus hat, mus noch eine andere Seite dieser Frage beleuchtet werden, namlich die Wirtschaftlichkeit. Der Wirtschaftlichkeit wegen sind alle Anstrengungen gemacht worden. Ihretwegen strebt man nach besseren Leistungen. Wirtschaftlichkeit bedeutet aber nicht allein bessere Leistungen, sondern in erster Linie Leistungen zu einem billigeren Preise.

Stehen nun die Karten in ihrer bestimmten Ordnung, dann sind noch sogenannte Leitkarten notwendig, um die einzelnen Gruppen der Kartei zu bezeichnen. Leitkarten sind starkere Karten mit einem Vorsprung, der uber die anderen Karten hinausragt und der das betreffende Ordnungszeichen tragt, also den Buchstaben, die Zahl, das Symbol oder die Kontobezeichnung.

Unter den Hilfsmitteln der Leistungssteigerung bei maschinisierten Buchhaltungen sind nicht die Maschinen selbst zu verstehen, sondern die Funktionen, die sie erfullen. So unterscheiden wir drei Gruppen von Hilfsmitteln, namlich solche der Beschleunigung, Arbeitszusammenlegung und Automatisierung.