Possible Eliashberg-Type Superconductivity Enhancement Effects in a Two-Band Superconductor MgB_{2} Driven by Narrow-Band THz Pulses.

We study THz-driven condensate dynamics in epitaxial thin films of MgB_{2}, a prototype two-band superconductor (SC) with weak interband coupling. The temperature and excitation density dependent dynamics follow the behavior predicted by the phenomenological bottleneck model for the single-gap SC, implying adiabatic coupling between the two condensates on the ps timescale. The amplitude of the THz-driven suppression of condensate density reveals an unexpected decrease in pair-breaking efficiency with increasing temperature-unlike in the case of optical excitation. The reduced pair-breaking efficiency of narrow-band THz pulses, displaying minimum near ≈0.7 T_{c}, is attributed to THz-driven, long-lived, nonthermal quasiparticle distribution, resulting in Eliashberg-type enhancement of superconductivity, competing with pair breaking.

Optically Triggered Néel Vector Manipulation of a Metallic Antiferromagnet Mn2Au under Strain.

The absence of stray fields, their insensitivity to external magnetic fields, and ultrafast dynamics make antiferromagnets promising candidates for active elements in spintronic devices. Here, we demonstrate manipulation of the Néel vector in the metallic collinear antiferromagnet Mn2Au by combining strain and femtosecond laser excitation. Applying tensile strain along either of the two in-plane easy axes and locally exciting the sample by a train of femtosecond pulses, we align the Néel vector along the direction controlled by the applied strain. The dependence on the laser fluence and strain suggests the alignment is a result of optically triggered depinning of 90° domain walls and their motion in the direction of the free energy gradient, governed by the magneto-elastic coupling. The resulting, switchable state is stable at room temperature and insensitive to magnetic fields. Such an approach may provide ways to realize robust high-density memory device with switching time scales in the picosecond range.

Analysis of Campylobacter jejuni isolates of various sources for loci associated with Guillain-Barré Syndrome.

Campylobacter jejuni is a major cause of the Guillain-Barré syndrome (GBS) and related diseases. These autoimmune diseases are caused by antibodies cross-reacting with the peripheral (GBS) and central neural tissue (Miller Fisher syndrome - MFS, Bicker-staff's brainstem encephalitis - BBE), leading to acute polyneuropathy. Recently, specific gene loci in C. jejuni have been distinguished which are associated with the onset of GBS, despite a molecular or phenotypic clustering. In this study, we used PCR to analyse C. jejuni isolates of different origin (i.e. bovine, poultry, human) for these genes. A total of 196 isolates were tested for cst-II and neuA. Of these, 101 isolates harboured the cst-II locus and 102 the neuA locus. Eighty-six isolates (44%) hold both genes. The frequency of cst-II in different sources of isolates of bovine, poultry and human isolates did not vary significantly (52, 50 and 52%, respectively). In contrast, the neuA locus was less often found in poultry isolates. Two human strains - from a family outbreak of campylobacteriosis (in 1989 in Austria) in which one person developed MFS - harboured both genes. Thus, although only one in more than 3000 patients with Campylobacter-associated enteritis develop GBS, about half of Campylobacter jejuni strains found in different environments are possibly able to cause GBS. These strains almost equally distributed in bovine, poultry and human isolates. Our results suggest that isolates associated with GBS are not selected by environmental or host-specific factors. Accordingly, this study indicates that host factors such as humoral and cellular immunity are possibly responsible for the development of these autoimmune diseases.

Transcriptional activation by the sexual pheromone and wounding: a new gene family from Volvox encoding modular proteins with (hydroxy)proline-rich and metalloproteinase homology domains.

The green alga Volvox represents the simplest kind of multicellular organism: it is composed of only two cell types, somatic and reproductive, making it suitable as a model system. The sexual development of males and females of Volvox carteri is triggered by a sex-inducing pheromone at a concentration of < 10-16 M. Early biochemical responses to the pheromone involve structural modifications within the extracellular matrix (ECM). By differential screenings of cDNA libraries made from mRNAs of pheromone-treated Volvox, four novel genes were identified that encode four closely related Volvox metalloproteinases that we use to define a new protein family, the VMPs. The existence of several features common to matrix glycoproteins, such as signal peptides, a (hydroxy)proline content of 12-25%, and Ser(Pro)2-4 repeats, suggest an extracellular localization of the VMPs within the ECM. Synthesis of VMP cDNAs is triggered not only by the sex-inducing pheromone, but also by wounding, and is restricted to the somatic cell type. Sequence comparisons suggest that the VMPs are members of the MB clan of zinc-dependent matrix metalloproteinases, although the putative zinc binding site of all VMPs is QEXXHXXGXXH rather than HEXXHXXGXXH. The presence of glutamine instead of histidine in the zinc binding motif suggests a novel family, or even clan, of peptidases. Like the matrixin family of human collagenases, Volvox VMPs exhibit a modular structure: they possess a metalloproteinase homology domain and a (hydroxy)proline-rich domain, and one of them, VMP4, also has two additional domains. Metalloproteinases seem to be crucial for biochemical modifications of the ECM during development or after wounding in the lower eukaryote Volvox with only two cell types, just as in higher organisms.

Response to the sexual pheromone and wounding in the green alga volvox: induction of an extracellular glycoprotein consisting almost exclusively of hydroxyproline.

The extracellular matrix (ECM) of Volvox is modified during development or in response to external stimuli, like the sex-inducing pheromone. It has recently been demonstrated that a number of genes triggered by the sex-inducing pheromone are also inducible by wounding. By differential screening of a cDNA library, a novel gene was identified that is transcribed in response to the pheromone. Its gene product was characterized as an ECM glycoprotein with a striking feature: it exhibits a hydroxyproline content of 68% and therefore is an extreme member of the family of hydroxyproline-rich glycoproteins (HRGPs). HRGPs are known as constituents of higher plant ECMs and seem to function as structural barriers in defense responses. The Volvox HRGP is also found to be inducible by wounding. This indicates that the wound response scenarios of higher plants and multicellular green algae may be evolutionary related.

[Discriminant analytic determination of prognostic variables from child psychiatric examination for school achievement in special education studies]. / Diskriminanzanalytische Bestimmung prognostischer Variablen aus der kinderpsychiatrischen Untersuchung für den Schulerfolg von Sonderschülern.

Scores on tests administered to learning disabled children in grade one during their examination by a child psychiatrist were analyzed for their predictive value with regard to the children's subsequent academic careers and type of school later attended. Upon starting school the learning disabled children exhibited marked deficits in intelligence and language and motor development. Variables predictive of the type of school to be attended later were intelligence scores and motor performance.

The sex-inducing pheromone and wounding trigger the same set of genes in the multicellular green alga Volvox.

The sex-inducing pheromone of the multicellular green alga Volvox carteri is a glycoprotein that triggers development of males and females at a concentration <10(-16) M. By differential screening of a cDNA library, two novel genes were identified that are transcribed under the control of this pheromone. Unexpectedly, one gene product was characterized as a lysozyme/chitinase, and the other gene product was shown to encode a polypeptide with a striking modular composition. This polypeptide has a cysteine protease domain separated by an extensin-like module from three repeats of a chitin binding domain. In higher plants, similar protein families are known to play an important role in defense against fungi. Indeed, we found that the same set of genes triggered by the sexual pheromone was also inducible in V. carteri by wounding.

[Follow-up of psychiatric disorders and specific developmental delay disorders in special education students]. / Verlauf psychiatrischer Störungen und umschriebener Entwicklungsrückstände bei Sonderschülern.

In a prospective longitudinal study 72 children who were attending a special school for children with learning disabilities in Erlangen were examined in 1990 and again in 1992/93. At the first examination the children's mean age was 7 years 1 month and at the second 8 years 10 months. The sample contained many more boys than girls. Reported here are the findings on the course of the psychiatric disorders and the specific developmental disorders of speech and language and motor function. There was a marked decrease in the prevalence of psychiatric disorders. Of the 17 children with a psychiatric disorder at follow-up, 13 (76%) also had a disorder at the start of the study and of the 23 with a psychiatric disorder at the start 13 (57%) still had a disorder at follow-up. Children with enuresis and those with disturbances of activity or attention had the best prognosis. The special school had a positive effect on conduct. The prevalence of specific developmental disorders also decreased over the two-year period. As expected, specific speech articulation disorders had the best prognosis. All other disorders had a poor prognosis. Increases in prevalence were mainly the result of different cutoff points for a given diagnosis at different ages. The high number of specific disorders of motor function at both time points is especially noteworthy.

[Intelligence and language performance of special education children at 7 and 9 years of age]. / Intelligenz und sprachliche Leistungen bei Sonderschulkindern mit 7 und 9 Jahren.

Prospective longitudinal data from children at a school for learning disabled were obtained. Intelligence and language scores were assessed at first grade and two years later. The results of two samples from Erlangen and München showed a high stability of the intelligence scores but less stability of the language scores. There were remarkable improvements in language comprehension. Expressive language had a constant lag compared with the test-standard of children of the same age; the articulation did improve as expected. The children from this special school still had problems with verbal short term memory.

[Psychomotor delay and psychiatric diagnoses in special education students]. / Motorische Entwicklungsstörungen und psychiatrische Diagnosen bei Sonderschülern.

76 first grade children of a special school for learning disabled were tested for specific developmental disorders of motor functions (SDDM). 15 children (19.7%), boys and girls proportionately, had a SDDM. This is a substantial increase compared to the unselected population. 8 children (15.5%) suffered from a specific disorder of body coordination and low finger-eye coordination. 4 children (5.3%) were found to have specific disorders of motor functions and specific language retardations. Isolated disorders of hand coordination were not found. 31% of the children with SDDM suffered from psychiatric disorders. Roughly the same percentage of psychiatric diagnosis was found in children without disorders of motor functions. A total of 24 children (33%) had impaired physical coordination: these children had significantly higher total scores in the Child Behavior Checklist (CBCL). Though this questionnaire was not sensitive for detection of disorders of motor functions.

[Reliability of the Child Behavior Checklist in a population of 6 to 8-year-old special education students]. / Untersuchung zur Anwendbarkeit der CBCL an einer Population von sechs- bis achtjährigen Sonderschülern.

66 children attending first grade at a special school for educationally subnormal children were examined medically and psychologically. Classification was done according to ICD-10. In addition, the parents were asked to rate their children's behavior with the "Child Behavior Checklist" by Achenbach and Edelbrock. The most common symptoms rated in this group of 6- to 8-year-old children were lack of concentration, speech and language problems, hyperactivity, demand for attention and arguing. The mean total score (cut-off score: 30) and the number of crucial items (cut-off score: at least two crucial items) differed significantly between the children with and those without psychiatric disorders. No significant correlation was found between the mean total score or the number of crucial items and the sex of the children or the other axes of the Multi-axial Classification of Child Psychiatric Disorders.

[Specific delays of language development in special education students]. / Umschriebene Sprachentwicklungsrückstände bei Sonderschülern.

The frequencies of specific language retardation and deficits in short term memory span are the subject of this epidemiological investigation of children attending the first grade of a special school for educationally subnormal children in Erlangen and München/Rosenheim. The children at the mean age of seven were examined according to the "Multi-axial Classification of Child Psychiatric Disorders". The following prevalences were found: 16 children (21%) of the sample from Erlangen and 24 children (33%) of the sample from München/Rosenheim had an specific language retardation, in both sample the most frequent disorders were retardations of the expressive language (11% and 21%). In both sample most children had substantially deficits in the acoustic short term memory span, while they were better on visual short term memory span. Significant correlations between acoustic short term memory span and specific language retardations were found.

[Multiple diagnoses and stresses in children of primary school age]. / Mehrfachdiagnosen und -belastungen bei Kindern im Grundschulalter.

The study was conducted to assess the consequences of multiple diagnoses and handicaps in children aged 6 to 8 years. Children were considered to be "multiply handicapped" if they suffered from two or more disorders or impairments included in the Multi-axial Classification Scheme. To this end children in special schools were compared with a random sample of children from three communities in Bavaria. As expected, all prevalences found in the population of children from special schools were substantially higher than those found in the random sample. Furthermore, the proportion of children with multiple handicaps in the special schools far exceeded what one would have expected based on the findings for the random sample. Most of the disturbances did not differ in respect to their comorbidity. But the mentally retarded children in the special schools were all "multiply handicapped". The importance of "multiple handicaps" for the assignment to special schools is discussed, as are the implications for the planning of services.