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International audience; Genetic differentiation occurs when gene flow is prevented, due to reproductive barriers or asexuality. Investigating the early barriers to gene flow is important for understanding the process of speciation. Here, we therefore investigated reproductive isolation between different genetic clusters of the fungus Penicillium roqueforti, used for maturing blue cheeses, and also occurring as food spoiler or in silage. We investigated premating and postmating fertility between and within three genetic clusters (two from cheese and one from other substrates), and we observed sexual structures under scanning electron microscopy. All intercluster types of crosses showed some fertility, suggesting that no intersterility has evolved between domesticated and wild populations despite adaptation to different environments and lack of gene flow. However, much lower fertility was found in crosses within the cheese clusters than within the noncheese cluster, suggesting reduced fertility of cheese strains, which may constitute a barrier to gene flow. Such degeneration may be due to bottlenecks during domestication and/or to the exclusive clonal replication of the strains in industry. This study shows that degeneration has occurred rapidly and independently in two lineages of a domesticated species. Altogether, these results inform on the processes and tempo of degeneration and speciation.

Gross-motor impairments are common after stroke, but efficacious and motivating therapies for these impairments are scarce. We present a novel musical sonification therapy especially designed to retrain gross-motor functions. Four stroke patients were included in a clinical pre-post feasibility study and were trained with our sonification training. Patients' upper-extremity functions and their psychological states were assessed before and after training. The four patients were subdivided into two groups, with both groups receiving 9 days of musical sonification therapy (music group, MG) or a sham sonification training (control group, CG). The only difference between these training protocols was that, in the CG, no sound was played back. During the training the patients initially explored the acoustic effects of their arm movements, and at the end of the training the patients played simple melodies by moving their arms. The two patients in the MG improved in nearly all motor function tests after the training. They also reported in the stroke impact scale, which assesses well-being, memory, thinking, and social participation, to be less impaired by the stroke. The two patients in the CG did benefit less from the movement training. Taken together, musical sonification may be a promising therapy for impairments after stroke.

Objective.–To determine whether injections of botulinum toxin could be of therapeutic value in the treatment of tension-type headache. Background.–Botulinum toxin A is very effective at reducing muscle tenderness and pain in many diseases. Increased muscle tension may contribute to tension-type headache. Methods.–We performed a double-blind, placebo-controlled study with 21 patients fulfilling the International Headache Society criteria for tension-type headache. Participants were randomly assigned to treatment (pericranial injection of 10 × 20 mouse units botulinum toxin A) or placebo (injection of isotonic saline in the same manner). Results.–After 4, 8, and 12 weeks, no significant differences between placebo and treatment could be observed (with respect to visual analog scale, frequency and duration of headache attacks, consumption of analgesics, pressure pain threshold, total tenderness score, and quality-of-life parameters). Conclusions.–The findings of our study strongly support the hypothesis that peripheral mechanisms, such as increased muscle tenderness, only play a minor role in the pathogenesis of tension-type headache.

Several intervening variables may influence motor evoked potentials (MEP) from transcranial magnetic stimulation (TMS). Among the most common are motor (e.g. executed or intended muscle contraction) and sensory factors. However, little is known about the effects of a well defined stressor on MEPs and thus on central motor control. We studied 11 healthy right-handed volunteers (five men and six women), aged 21-32 years (mean 25.2 years. SD = 3.5). All subjects underwent a 20 min rest and a 20 min stress period (sequence-controlled, cross-over design). The stressor employed a competitive videogame. MEPs from the left abductor digiti minimi muscle were obtained immediately after rest and stress. We found that six (54.5 per cent) subjects presented a significant increase (p < 0.05) of MEP amplitudes from rest to stress, three (27.3 per cent; p < 0.05) decreased, and two (18.2 per cent) did not change, F- and M-waves did not change significantly. Psychological testing (state and trait anxiety inventory, STAI) revealed that individuals who presented an increase in MEP latency scored lower in state and trait anxiety than others, probably mdicating a lower vulnerability to stress. We believe that the observed increase in MEP amplitudes, combined with a decrease in MEP latency, can be regarded as neurophysiological evidence of stress-induced facilitation related to higher excitability of the corticospinal system and/or presynaptic neurons.

Propofol is a widely used general anaesthetic with growing usage outside anaesthesia. Despite its potential for abuse only five cases of propofol dependency have yet been reported. These comprise health care professionals with easy access to the drug. This is the first reported case of propofol dependency in a lay person. One should be aware of the abuse potential of propofol with regard to its growing use outside the context of general anaesthesia.

The prefrontal cortex plays an important role in central motor control. We have examined whether prefrontal repetitive transcranial magnetic stimulation (rTMS) induces changes of motor cortex excitability determined by motor evoked potentials (MEPs) following single-pulse TMS. We studied 18 healthy volunteers stimulated at 5 Hz with 10% subthreshold prefrontal vs. occipital rTMS for 12 s. MEPs from the flexor carpi radialis muscle after single-pulse vertex stimulation were recorded during rTMS at 0, 4, 8, and 12 s. MEP areas decreased significantly after 8 s of prefrontal rTMS (P < 0. 05) but not after occipital rTMS. We conclude that rTMS of the prefrontal cortex may inhibit the primary motor areas.

Transcranial magnetic stimulation was used to study motor evoked potentials (MEPs) of leg muscles in controls and patients with multiple sclerosis (MS) before and after walking. In controls, MEP areas were significantly reduced after walking. A similar or greater reduction was seen in most patients, although there was a wide range of values. The M waves were unchanged. We conclude that walking induces functional changes of the corticospinal system and/or connected neurons contributing to central fatigue, especially in patients with MS.

Im Oktober des letzten Jahres konnte die Kultusministerin des nordlichsten der neuen Bundeslander feststellen, das die 1. Stufe der personellen Erneuerung der Hochschulen abgeschlossen sei. Mecklenburg-Vorpommern war damit das erste der neuen Bundeslander, das diese Zwischenstufe des Umbaus des Hochschulsystems erreichte. Fur die Physik lautet das Ergebnis, das etwa drei Viertel der C2-, C3- und C4-Professuren an den beiden Universitaten des Landes in Greifswald und Rostock sowie an der neugegrundeten Fachhochschule Wismar durch Ubernahme von qualifizierten Fachkollegen besetzt werden konnten. Die restlichen Positionen werden nach dem ublichen Berufungsverfahren ausgeschrieben.

Als Antwort auf den verscharften weltweiten Wettbewerb in der Mikroelektronik wurde mit JESSI eine europaische Forschungsinitiative fur eine eigenstandige Mikroelektronik-Industrie in Europa gegrundet. Anfang 1992 ist JESSI in seine Hauptphase getreten – Anlas genug, das bisher Erreichte vorzustellen.

Mit den Worten, die Berliner Physikalische Gesellschaft war „ein Kreis aufstrebender Talente, der durch die entschlossene Selbsthilfe eines freiwilligen Zusammenschlusses, eine Statte schuf, an der sich durch lebhafte, anregende Wechselbeziehung eine seltene Blute geistigen Lebens entfaltete”, kennzeichnete der Mathematiker Felix Klein die Physikalische Gesellschaft zu Berlin [1]. In der Tat gilt dieser Bezug auf die Physiker selbst -nach § 3 der DPG-Satzung - auch heute noch. Er spiegelt sich auch in den Themen der Empfehlungen und Stellungnahmen wider, die die DPG abgegeben hat. Dennoch hat die Aufgabe, fur die Physik und die Physiker zu wirken, die DPG immer wieder veranlast, Empfehlungen auch nach ausen an die politischgesellschaftliche Umwelt zu richten.

Einer Schilderung der Entwicklung der Physikalischen Institute und Fachbereiche von 1950 bis 1977 folgt die Darstellung der Entwicklung der Studentenzahlen im Fach Physik seit 1960 sowie der voraussichtlichen weiteren Entwicklung. Einige Schlusfolgerungen schliesen den Uberblick ab.

Stellungnahmen der Konferenz der Fachbereiche Physik (KFP) und der Gesellschaft fur Didaktik der Chemie und Physik (GDCP) zu den „Einheitlichen Prufungsanforderungen in der Abiturprufung/Chemie/Physik”.