Stimulated Amplification of Propagating Spin Waves

Spin-wave amplification techniques are key to the realization of magnon-based computing concepts. We introduce a novel mechanism to amplify spin waves in magnonic nanostructures. Using the technique of rapid cooling, we create a nonequilibrium state in excess of high-energy magnons and demonstrate the stimulated amplification of an externally seeded, propagating spin wave. Using an extended kinetic model, we qualitatively show that the amplification is mediated by an effective energy flux of high energy magnons into the low energy propagating mode, driven by a nonequilibrium magnon distribution.

Photoswitchable Bis(amidopyrroles): Modulating Anion Transport Activity Independent of Binding Affinity

Toward photocontrol of anion transport across the bilayer membrane, stiff-stilbene, which has dimethyl substituents in the five-membered rings, is functionalized with amidopyrrole units. UV-vis and 1H NMR studies show high photostability and photoconversion yields. Where the photoaddressable (E)- and (Z)-isomers exhibit comparable binding affinities, as determined by 1H NMR titrations, fluorescence-based transport assays reveal significantly higher transport activity for the (Z)-isomers. Changing the binding affinity is thus not a necessity for modulating transport. Additionally, transport can be triggered in situ by light.

Hemithioindigo-Based Trioxobicyclononadiene: 3D Multiswitching of Electronic and Geometric Properties

Molecular photoswitches that offer simultaneous precise control over geometrical and electronic changes are rare yet highly sought tools for the development of responsive nanosystems. Here we present such an advantageous combination of property control within a novel multiphotoswitch architecture. Hemithioindigo-based trioxobicyclononadiene (HTI-TOND) offers a rigid three-dimensional molecular structure that undergoes different exotic rearrangement reactions upon photochemical and thermal signaling. Three to four different states with distinct geometric and electronic properties can be accessed reversibly in high yields within this molecular framework. Thus, a highly promising and unique switching tool has become available to instill the next level of addressability at the smallest scales.

Controlling the Nonlinear Relaxation of Quantized Propagating Magnons in Nanodevices

Relaxation of linear magnetization dynamics is well described by the viscous Gilbert damping processes. However, for strong excitations, nonlinear damping processes such as the decay via magnon-magnon interactions emerge and trigger additional relaxation channels. Here, we use space- and time-resolved microfocused Brillouin light scattering spectroscopy and micromagnetic simulations to investigate the nonlinear relaxation of strongly driven propagating spin waves in yttrium iron garnet nanoconduits. We show that the nonlinear magnon relaxation in this highly quantized system possesses intermodal features, i.e., magnons scatter to higher-order quantized modes through a cascade of scattering events. We further show how to control such intermodal dissipation processes by quantization of the magnon band in single-mode devices, where this phenomenon approaches its fundamental limit. Our study extends the knowledge about nonlinear propagating spin waves in nanostructures which is essential for the construction of advanced spin-wave elements as well as the realization of Bose-Einstein condensates in scaled systems.

Shifted factor analysis for the separation of evoked dependent MEG signals

Decomposition of evoked magnetoencephalography (MEG) data into their underlying neuronal signals is an important step in the interpretation of these measurements. Often, independent component analysis (ICA) is employed for this purpose. However, ICA can fail as for evoked MEG data the neuronal signals may not be statistically independent. We therefore consider an alternative approach based on the recently proposed shifted factor analysis model, which does not assume statistical independence of the neuronal signals. We suggest the application of this model in the time domain and present an estimation procedure based on a Taylor series expansion. We show in terms of synthetic evoked MEG data that the proposed procedure can successfully separate evoked dependent neuronal signals while standard ICA fails. Latency estimation of neuronal signals is an inherent part of the proposed procedure and we demonstrate that resulting latency estimates are superior to those obtained by a maximum likelihood method.

[Somatoform Pain Disorder and Fibromyalgia--difficulties and problems of their judgement in German consultant praxis]

In the last 20 years the fibromyalgia syndrome and the somatoform pain disorder became more and more important in clinical medicine and in legal affairs. The consultant meets progressive more specific questions, which are not sufficient mentioned in the medico-legal recommendations and at least national "guide-lines" of medical societies.

METHODS

By an casuistic approach we try to show the implications of the often seen comorbidity of these two common disorders (i.e. the fibromyalgia syndrome and the somatoform pain disorder) both in legal and in medical perspectives.

RESULTS

At the moment the medico-legal recommendations and the national "guide-lines" of medical societies are often not sufficient to decide many of the the legal implications and consultant questions that result from the comorbidity ot these often seen "modern disorders". Therefore we try to develop in an single case the solution principles of appropriate judgement for the functional effects of comorbidity with fibromyalgia syndrome and the somatoform pain disorder.

CONCLUSIONS

Because of the wide spectrum of comorbid symptoms between these both disorders one must analyse any specific case very exactly and prove the individual functional implications of the comorbidity in correlation to the degree of impairement. We try to show in an casuistic presentation the possibilities of judgement according the appointments of german law.

["Agoraphobia--place anxiety/place fear--place-related vertigo". The classical description of place anxiety by Carl Westphal and Emil Cordes and its significance for the history of the concept and current discussion of anxiety disorders]

We discuss the history of "agoraphobia" and related descriptions as the "Platzangst" from M. Benedikt and the artile of E. Cordes, who used the same title "agoraphobia" as Westphals original paper. It is remarkable that Westphal and Cordes recognized the psychological character of the phenomenon, whereas Benedikt in 1870 suspected a neuroophthalmological origin for his "Platzschwindel". Regarding the details of these first three descriptions one can show that the primary authorities set up a discussion, which is still going on: The relation between agoraphobia, dizziness, fear and panic is until now object of many controversies, as shown in the final chapter.

[A pharmaceutical of the century will be 100. A historical vignette on the introduction of acetylsalicylic acid to the market in 1899]

This article describes the historic roots of acetylsalicylic acid (ASA) from the first experiments at 1800 until the introduction into the pharmaceutical market in 1899. In 1869, Hermann Kolbe enlightened the chemical structure of salicylic acid, which was used at that time as an analgetic and antipyretic drug. Because of the side effects, for example the irritation of the stomach, analytical chemists and pharmacologists searched for chemical modifications. In August 1897 Felix Hoffmann (1868-1946) was successful in acetylizing the salicylic acid to acetylsalicylic acid (ASA). Between 1897 and 1899 Kurt Witthauer (1865-1911) collected clinical data and experiences on the efficiency of ASA as an analgetic and antipyretic drug. In 1899 ASA was introduced into the pharmaceutical market as Aspirin and became soon one of the most successful drugs of its time. The indication exceeds analgesia in the mean time and to prophylaxis of myocardial ischaemia or cerebral stroke, among others.

[The beginning of Emil Kraepelin's classification of psychoses. A historical-methodological reflection on the occasion of the 100th anniversary of his "Heidelberg Address" 27 November 1898 on "nosologic dichotomy" of endogenous psychoses]

Emil Kraepelin's (1856-1926) famous lecture "Zur Diagnose und Prognose der Dementia praecox" was held in Heidelberg 100 years ago on 27. November 1889. In this lecture Kraepelin suggested for the first time his famous "nosological dichotomy" between the group of "manisch-depressives Irresein" and the so-called "Dementia-praecox-Gruppe". This dichotomy became world famous since the publication of his "Lehrbuch der Psychiatrie", 6th edition 1899. Kraepelin founded his psychiatric system on outcome observations and the nosological principles of Kahlbaum. His nosology is very influential to the present day. The revision of American psychiatry in the 1970's and 1980's is unthinkable without Kraepelin's concept. Therefore the name "Neo-Kraepelinianism" was created.

[The pharyngeal anxiety syndrome: globus perception and pharyngeal sensations as an oligosymptomatic abortive form of an anxiety disorder? Nosologic, diagnostic and therapeutic aspects, illustrated with a case]

Since the introduction of the modern psychiatric diagnosis systems anxiety disorders have been intensively discussed. As clinical subtypes in panic disorder the cardial type and the vestibular type are widely accepted. We describe in a case report another of these subtypes, the pharyngeal type; it is characterised by symptoms that are related to the pharynx such as feeling a lump in the throat, swallow disturbance or pain in the pharynx region. It may therefore be called "throat-anxiety syndrome" or "phagophobia". Nosological implications are also discussed.

[The "Illenau Psychiatric School"--on the significance of the "model institution" as an educational site]

The great importance of the "illenau", the so-called "first model asylum of the Germans" (letter) has been increasingly appreciated in recent years. This article describes the "illenau" especially as place of education for young psychiatrists. It seems legitimate to speak of the "illenau psychiatric school" in respect of its function for the practical education of young psychiatrists, but not as a special academic mode of teaching or research.

[Philippe Pinel and the legendary "unchaining" at the Paris Bicêtre (1793) and Salpêtrière (1795) Hospitals. II: Historical background, allegorical descriptions discipline generated myths]

Part I of this article has described Pinels carrier upto the 1790ies. This second part concentrates of the actual events and the general historical backgrounds of the so-called "chain liberation." This--in our opinion--cannot be regarded as one singular act, but as symbol for a complex and multistage process. The very common conception of a selective act of "chain liberation" is very simplified and influenced by the "myth of Pinel, " built by the 19th century psychiatrists and historians. Nevertheless: a scientifically sophisticated biography founded on archives material is yet expected.

[Philippe Pinel and the legendary "chain liberation" in the Bicêtre (1793) and Salpêtrìere (1793) Paris hospitals. I: Pinel's personality and previous reform attempts]

Philippe Pinel is generally regarded as the leading con-founder of scientific psychiatry. His "chain liberation" of the insane is in this context often seen as breakbrough to an human conception of psychiatry. This article describes in two parts the historical backgrounds of Pinels activities and analyses the discipline-genetic myths connected with them. Part one follows Pinels carrier upto the 1790ies and describes contemporary efforts to reform psychiatric asylums.

[Bernhard von Gudden (1824-1886)--institutional psychiatrist, brain anatomist and influential university teacher]

Nowadays B. v. Gudden is primary known as psychiatrist of the dream-king Ludwig II.; nevertheless he was not only a doctor of the top people, but one of the great clinicians, neuropathologists and psychiatric teachers in the last third of the 19th century. Trained at Siegburg and Illenau, the leading institutions of german mental hospital psychiatry, he was formed by Conolly's "no-restraint"-movement as well as by Griesingers neuropathological concepts. So he became one of the most influential academic teachers of german psychiatry, who attracted important pupils like August Forel or Emil Kraepelin.

[Wagner von Jauregg and development of malaria therapy]

In this history of psychiatric therapy the progressive paralysis deserves special interest: for the first time an organic psychosis was treatable successfully by a procedure found by scientific methods. This article describes life and work of Julius Wagner, Ritter von Jauregg (1857-1940) and remembers the introduction of the malaria-therapy, which was developed by Wagner 75 years ago.

Development of a multiple thin-film semimicro DC-probe for intracerebral recordings

A thin-film multiple-electrode probe for measuring de potentials at eight sites with interdistances of 1 mm was constructed for the investigation of slow potential changes in deep regions of the human brain during surgery. The thin-film electrodes had to be placed on curved cylinder-shaped surgical instruments with dimensions of 2 mm diameter and 33 cm length used with the Freiburg stereotactic equipment. Several novel technological steps had to be introduced for the solution of the encountered problems: 1) Structuring of the metal layers on curved substrates was accomplished by using flexible masks. 2) Special feed-through technologies had to be invented in order to obtain reliable connections between the thin-film sensors and the copper wires inside the stereotactic instrument. 3) Thin-film Ag-AgCl electrodes had to be formed in order to obtain satisfying recordings of slow potential changes below 10 Hz. Slow potential changes were recorded from different depths in interdistances of only 1 mm with these new miniaturized thin film Ag-AgCl electrodes and bipolar recordings with an electrode interdistance of only 3 mm showed clearly the appearance of Bereitschaftspotentials.