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Powders of multidomain magnetite were subjected to fatigue-related cyclic loading at ambient conditions between 30 and 500°C using a dynamical mechanical analysis system. The mechanical losses, tan δ, are sensitive to the loading frequency and correlate with decreasing coherent crystallite size of the magnetite and its lattice distortion. While the selected loading frequencies are similar to those observed during earthquake propagation, the observed signatures of magnetic fatigue are discussed towards understanding the physics of natural and human-induced seismic events.

Aims Borderline personality disorder (BPD) is characterized by self-regulation deficits, including impulsivity and affective lability. Transference-focused psychotherapy (TFP) is an evidence-based treatment proven to reduce symptoms across multiple cognitive–emotional domains in BPD. This pilot study aimed to investigate neural activation associated with, and predictive of, clinical improvement in emotional and behavioral regulation in BPD following TFP. Methods BPD subjects (n = 10) were scanned pre- and post-TFP treatment using a within-subjects design. A disorder-specific emotional–linguistic go/no-go functional magnetic resonance imaging paradigm was used to probe the interaction between negative emotional processing and inhibitory control. Results Analyses demonstrated significant treatment-related effects with relative increased dorsal prefrontal (dorsal anterior cingulate, dorsolateral prefrontal, and frontopolar cortices) activation, and relative decreased ventrolateral prefrontal cortex and hippocampal activation following treatment. Clinical improvement in constraint correlated positively with relative increased left dorsal anterior cingulate cortex activation. Clinical improvement in affective lability correlated positively with left posterior-medial orbitofrontal cortex/ventral striatum activation, and negatively with right amygdala/parahippocampal activation. Post-treatment improvements in constraint were predicted by pre-treatment right dorsal anterior cingulate cortex hypoactivation, and pre-treatment left posterior-medial orbitofrontal cortex/ventral striatum hypoactivation predicted improvements in affective lability. Conclusions These preliminary findings demonstrate potential TFP-associated alterations in frontolimbic circuitry and begin to identify neural mechanisms associated with a psychodynamically oriented psychotherapy.

In this introductory review, we give an overview of the computational chemistry methods commonly used in the field of metal–organic frameworks (MOFs), to describe or predict the structures themselves and characterize their various properties, either at the quantum chemical level or through classical molecular simulation. We discuss the methods for the prediction of crystal structures, geometrical properties and large-scale screening of hypothetical MOFs, as well as their thermal and mechanical properties. A separate section deals with the simulation of adsorption of fluids and fluid mixtures in MOFs.

Background: As conventional immunotherapy is less efficacious in patients with allergic multi-sensitivities compared with mono-sensitized subjects, new intervention strategies are needed. Therefore, an allergen chimer was genetically engineered for treatment of multi-sensitization with birch and grass pollen on the basis of mucosal tolerance induction. Methods: The major birch pollen allergen Bet v 1 served as a scaffold for N- and C-terminal linkage of the immunodominant peptides of the grass pollen allergens Phl p 1 and Phl p 5 and this new construct was cloned and expressed in Escherichia coli. After purification, physicochemical and immunological characterization the chimer was used for intranasal tolerance induction prior to poly-sensitization with Bet v 1, Phl p 1 and Phl p 5. Results: The immunological characterization revealed that the conformation of Bet v 1 within the chimer was comparable to that of natural as well as recombinant Bet v 1. The chimer was immunogenic in mice for T and B cell responses to the three allergens. Intranasal application of the chimer prior to poly-sensitization significantly suppressed humoral and cellular allergen-specific Th2 responses and prevented development of airway inflammation upon allergen challenge. Moreover, local allergen-specific IgA antibodies were induced by the chimer. The mechanisms of poly-tolerance induction seemed to be mediated by regulatory cytokines, since TGF-β and IL-10 mRNA in splenocytes were upregulated and tolerance was transferable with these cells. Conclusion: The data indicate that such allergen chimers harboring several unrelated allergens or allergen peptides could serve as mucosal polyvalent vaccines for prevention of multi-sensitivities.

Background: Prior studies suggest racial/ethnic differences in the associations between alcohol misuse and spouse abuse. Some studies indicate that drinking patterns are a stronger predictor of spouse abuse for African Americans but not whites or Hispanics, while others report that drinking patterns are a stronger predictor for whites than African Americans or Hispanics. This study extends prior work by exploring associations between heavy drinking, alcohol-related problems, and risk for spouse abuse within racial/ethnic groups as well as variations associated with whether the perpetrator is drinking during the spouse abuse incident. Methods: Cases (N=7,996) were all active-duty male, enlisted Army spouse abusers identified in the Army's Central Registry (ACR) who had also completed an Army Health Risk Appraisal (HRA) Survey between 1991 and 1998. Controls (N=17,821) were matched on gender, rank, and marital and HRA status. Results: We found 3 different patterns of association between alcohol use and domestic violence depending upon both the race/ethnicity of the perpetrator and whether or not alcohol was involved in the spouse abuse event. First, after adjusting for demographic and psychosocial factors, weekly heavy drinking (>14 drinks per week) and alcohol-related problems (yes to 2 or more of 6 alcohol-related problem questions, including the CAGE) were significant predictors of domestic violence among whites and Hispanics only. Also for the white soldiers, the presence of family problems mediated the effect of alcohol-related problems on spouse abuse. Second, alcohol-related problems predicted drinking during a spouse abuse incident for all 3 race groups, but this relation was moderated by typical alcohol consumption patterns in Hispanics and whites only. Finally, alcohol-related problems predicted drinking during a spouse abuse incident, but this was a complex association moderated by different psychosocial or behavioral variables within each race/ethnic group. Conclusion: These findings suggest important cultural/social influences that interact with drinking patterns. Language: en

Summary Background Profilins are cross-reactive plant allergens responsible for multiple pollen sensitization and pollen-associated food allergy. While it is assumed that profilins from different species are immunologically equivalent, some studies suggest partial or even lacking IgE cross-reactivity between certain profilins. Objective We aimed to obtain a semi-quantitative assessment of the contributions of conserved and species-specific epitopes to IgE binding of plant profilins. Methods We compared model structures of profilins from timothy, mugwort, celery and bell pepper with crystal structures of birch and latex profilins. We predicted potential conformational epitopes that consisted of contiguous patches of at least 20% surface-exposed residues. Celery and timothy profilins were purified from their natural sources, and profilins from birch, mugwort, bell pepper and latex were expressed in Escherichia coli. The structural integrity of all purified proteins was confirmed by circular dichroism spectroscopy. IgE ELISAs and ELISA inhibitions using sera from 22 profilin-sensitized allergic patients were carried out. Results Peptide backbone conformations of all six profilins were highly similar. Nine variable epitopes and two containing high proportions of conserved residues were predicted. IgE from all sera bound to all tested profilins and the amounts were highly correlated. However, IgE inhibition experiments revealed that up to 60% of total IgE binding was mediated by species-specific epitopes. The extent of cross-reactivity among profilins from timothy, birch, latex and celery was greater than cross-reactivity to mugwort and bell pepper profilins. This pattern was mirrored by sequence similarities among one of the predicted variable epitopes. Patients with IgE to cross-reactive epitopes displayed allergic reactions to a greater number of plant foods than patients having IgE directed to species-specific epitopes. Conclusion The large extent of cross-reactivity among plant profilins justifies using a single profilin for diagnosis. However, the fine specificity of IgE directed to variable epitopes may influence the clinical manifestation of profilin sensitization.

For the case of eye tumor therapy with protons, improvements are introduced compared to the standard dose calculation which implies straight-line optics and the constant-density assumption for the eye and its surrounding. The progress consists of (i) taking account of the lateral scattering of the protons in tissue by folding the entrance fluence distribution with the pencil beam distribution widening with growing depth in the tissue, (ii) rescaling the spread-out Bragg peak dose distribution in water with the radiological path length calculated voxel by voxel on ray traces through a realistic density matrix for the treatment geometry, yielding a trajectory dependence of the geometrical range. Distributions calculated for some specific situations are compared to measurements and/or standard calculations, and differences to the latter are discussed with respect to the requirements of therapy planning. The most pronounced changes appear for wedges placed in front of the eye, causing additional widening of the lateral falloff. The more accurate prediction of the dose dependence at the field borders is of interest with respect to side effects in the risk organs of the eye.

Numerical studies with a spherical dynamo model have shown two remarkable phenomena. The model consists of a spherical body of an electrically conducting incompressible uid surrounded by free space. In addition to a rotation of the body an inner motion due to a given forcing is considered which satisfies a no–slip condition at the boundary. The full interaction of magnetic field and motion is taken into account. Starting from a fluid motion capable of dynamo action and a very weak magnetic field it was observed that the growing magnetic field destroys the dynamo property of the motion and then decays, and that the system ends up in a state with another motion incapable of dynamo action and zero magnetic field. In another case with a motion unable to prevent small magnetic fields from decay it proved to be possible that stronger magnetic fields deform it so that a dynamo starts to work which enables the system to approach a steady state with a finite magnetic field.

Summary Bleak (Alburnus alburnus, L.) and chub (Leuciscus cephalus, L.) populations from Rivers Main, Isar and Danube were screened for different banding patterns in random amplified polymorphic DNA (RAPD) and random amplified microsatellite polymorphism (RAMPO) fingerprints. In chub two markers and in bleak four marker systems were established that enabled us to distinguish fishes from either population. In bleak a 600 bp RAPD fragments was detected in all samples from the River Main but in none from the River Danube. In order to find out whether these polymorphic RAPD and RAMPO bands were population or River specific, two further bleak populations from River Main and one additional bleak population from River Danube were checked through for these markers. Two further marker systems based on point mutations were also applied to the bleak samples. Marker frequencies differed significantly between bleak populations from River Main and bleaks from River Danube, but populations of the same River showed very similar marker frequencies. Thus, bleaks from the River Danube can be clearly distinguished from bleaks originating from the River Main. For chub two RAPD markers displaying different frequencies in the populations of the Rivers Main and Isar are presented. Zusammenfassung Unterscheidung von Lauben-bzw. Aitelpopulationen in Main, Isar und Donau mit Hilfe molekulargenetischer Marker Mit Hilfe von RAPD und RAMPO wurden Lauben- bzw. Aitelpopulationen aus den Flussen Main, Isar und Donau auf unterschiedliche Bandenmuster uberpruft. Beim Aitel konnten zwei, bei der Laube 4 Markersysteme etabliert werden, die es ermoglichen, Tiere der einzelnen Populationen genetisch zu unterscheiden. Bei der Laube wurde ein 600 bp RAPD-Fragment gefunden, das in allen Proben aus dem Main, aber in keiner aus der Donau vorhanden war. Um die Frage zu klaren, welche der polymorphen RAPD- oder RAMPO-Banden populations-oder flusspezifisch waren, wurden zwei weitere Laubenpopulationen des Mains und eine aus der Donau auf diese Marker untersucht, und zwei zusatzliche Marker in Form von Punktmutationen angewendet. Die Markerfrequenzen unterschieden sich signifikant zwischen Main- und Donaupopulationen, waren aber sehr ahnlich innerhalb eines Flusses. Damit konnen Lauben des Mains eindeutig von solchen der Donau unterschieden werden. Fur den Aitel werden zwei RAPD-Marker mit unterschiedlichen Frequenzen in Main und Donau vorgestellt.

Psychologists and baseball players were among those Americans who formed professional associations in the last quarter of the nineteenth century. Psychologists used laboratory tasks to quantify mental and behavioral processes while sportswriters and baseball organizers measured individual and team performance. The most popular baseball player of the 1920s, George Herman “Babe” Ruth, possessed superior batting skills that were evident in the statistical indices of baseball performance. In 1921, he was brought to the psychological laboratory at Columbia University to perform standard laboratory tasks in an effort to discover the basis for his success in hitting home runs and to suggest the potential of tests for identifying future baseball stars. Baseball's addiction to quantitative indices of performance was thus brought together with a new science devoted to quantitative assessment and a desire to make such assessments useful. The attempt to analyze the basis of Ruth's batting skills is part of the history of applied psychology, sport psychology, and popular interest in the science of psychology. © 1998 John Wiley & Sons, Inc.

Recent progress in the computation of thermodynamic properties of guest molecules in zeolites, using classical molecular simulation techniques, is reviewed. It is shown that grand canonical Monte Carlo simulations, using statistical biaising for studying large anisotropic molecules, together with an appropriate guest−guest force field, may provide a reasonably accurate prediction of single component and binary mixture adsorption data for systems such as normal and branched alkanes, benzene, alkyl benzene isomers and halocarbon molecules in a variety of aluminosilicate hosts. The Monte Carlo algorithms used to obtain reliable thermodynamics data (adsorption isotherms and heats) are discussed as well as the newly developed semiempirical force fields, which allow a better transferability of the potential parameters from one guest/host system to another.

Tetrads which are parallelpropagated along time-like geodesics in static spherically symmetric spce-times are constructed. Its connection with the geodesic precession is explained. Moreover, we express the solution of the equations of geodesic deviation in terms of the Killing vectors and the fourvelocity.

For static spherically symmetric space-times the equations of geodesic deviation are solved for circular geodesics. We discuss the connection between the obtained solutions and the stability behaviour of the geodesics. The perihelion shift for test bodies moving on nearly circular geodesics is also derived. Fur die allgemeine statische kugelsymmetrische Raum-Zeit werden die Gleichungen der geodatischen Deviation fur kreisformige Geodaten gelost. Wir diskutieren den Zusammenhang dieser Losungen mit dem Stabilitatsverhalten der Geoaten. Die Perihelverschiebung fur Probekorper, die sich auf nahezu kreisformigen Geodaten bewegen, wird ebenfalls angegeben.

Comparison of nucleotide sequences of the growth hormone gene of two populations of bleak from the Main Donau Rivers, Southern Germany, revealed an A/T point mutation resulting in an AluI restriction fragment length polymorphism. The frequencies of alleles T and A are 0–95/0–05 in the Donau and 0–62/0–38 in the Main.

How is chemistry standing in the land of Lavoisier, while we re celebrating the 100th anniversary of the Nobel Prize in Chemistry to Paul Sabatier and Victor Grignard, within a rapidly changing higher education and research landscape? France has a long-standing tradition of research and innovation in chemistry, and its chemical industry (ranked fifth in the world) is still a strong pillar of French economic development. More than 3300 chemical companies directly employ 200000 people (inducing 600000 indirect jobs). Most of these are small or medium companies, together with some large industrial groups such as Total, Arkema, Rhodia, Michelin, and Air Liquide. This strong industrial activity has generated, in the first part of the 20th century, the foundation of several chemistry and chemical engineering graduate schools all over the country, attracting very good students educated as chemical engineers to amasters level. On the academic side, some 5300 researchers and 2700 technical staff work in chemistry laboratories and teams, located in the most important French academic cities. All of the main research topics are addressed in the core of chemical science and in all of its interfaces with physics (such as materials science, nanosciences, soft matter, spectroscopies), life sciences (medicinal chemistry, bioinspired chemistry, structural biology), and engineering (optoelectronic devices, energy storage, metallurgy).

In the framework of TREDER'S dynamics, in which according to the MACH-EINSTEIN-doctrin the inertial masses are induced by the gravitational interaction with the particles of the cosmos, we calculate the secular post-NEWTONian effects for the restricted three-body problem. The dominant secular post-NEWTONian variation of nodes and apsides is shown to be the same as in EINSTEIN'S theory of gravitation. The formulation of the gravodynamics in the HERTZian configuration space allows – as in General Relativity – the explanation of the effect as an “geodetic precession” of the lines of nodes and apsides. Im Rahmen von TREDERS Dynamik, in der entsprechend der MACH-EINSTEIN-Doktrin die tragen Massen durch die gravitative Wechselwirkung mit den Teilchen des Kosmos erzeugt werden, berechnen wir sakulare nach-NEWTONsche Effekte fur das restringierte 3-Korperproblem. Die dominante sakulare nach-NEWTONsche Variation der Knoten und Apsiden ist von gleicher Grose wie fur die EINSTEINsche Gravitationstheorie. Geht man zur Formulierung der Gravodynamik im ertzschen Konfigurationsraum uber, so last sich der Effekt wie in der Allgemeinen Relativitatstheorie als “geodatische Prazession” der Knoten- und Apsidenlinie erklaren, wie dies TREDERS Interpretation dieser Dynamik entspricht.

The meteoritic occurrence of rhonite-bearing calcium and aluminum rich inclusions (CAIs) appears to be restricted to the Allende meteorite. These inclusions, however, are very scarce as only four are known to the author. This report is primarily concerned with the descriptive mineralogy of one of these rare CAIs. The inclusion contains, in decreasing order of abundance, melilite (Ak15-Ak55), spinel, fassaite, rhonite, perovskite, grossular, Ni-Fe metal, hibonite, troilite, a vanadium-iron oxide (20–27 wt % V2O3), molybdenite, geikielo-ilmenite and magnetite. Although this mineral assemblage formed under nonequilibrium conditions from a molten drop, the coarse grained texture does not indicate rapid crystallization. Local chemistries evidently played a significant role in the formation of metastable phase relationships and symplectites, thereby confounding the construction of a plausible thermal history for this CAI.

Grossular garnet has been observed in several white inclusions in the Allende meteorite. Compositions range from Gro(95)Py(5) to Gro(88)Py(12) in five inclusions. Its mottled appearance indicates that it crystallized from a glass of near-grossular composition and not by a solid-state reaction between wollastonite, anorthite, and melilite. These grossular-bearing inclusions either condensed directly as metastable liquids from the solar nebula or, if initial solid condensates were liquefied, by some subsequent heating process. In either case, a prolonged residence time in a thermal blanket appears necessary to effect crystallization of the grossular.

In the framework of TREDERS' tetrad theory of gravitation the interaction of pole-particles is considered in post-NEWTONian approximation. The perihelion shift for the two-body problem is calculated for different matter-field-couplings. In general it depends not only from the sum of the masses but also from the reduced mass. The additional term is connected with the absorption of gravitation. Im Rahmen der TREDERschen Tetradentheorie wird die Wechselwirkung von Polteilchen in nach-NEWTONscher Naherung betrachtet. Die Perihelbewegung fur das Zweikorperproblem wird fur verschiedene Materie-Feld-Kopplungen angegeben. Sie hangt im allgemeinen nicht nur von der Summe der beiden Massen, sondern auch von der reduzierten Masse ab. Der zusatzliche Term ist eine Folge der Absorption der Schwere.

Vor gerade erst zehn Jahren begannen Gerd Binnig und Heinrich Rohrer am IBM-Forschungslabor in Zurich, eine neue, hochauflosende Methode zur spektroskopischen Untersuchung dunner Oxidfilme zu entwickeln. Das Ergebnis ihrer unkonventionellen Vorgehensweise war das Raster-Tunnelmikroskop (RTM) [1]. Es sollte sehr bald die ursprunglichen Erwartungen hinsichtlich seines lateralen Auflosungsvermogens in topographischen und energieselektiven Abbildungstechniken und vor allem hinsichtlich der Breite seiner Anwendungsmoglichkeiten weit ubertreffen. Heute, nach drei internationalen Konferenzen seit 1986 und weit uber eintausend Publikationen zum Thema Tunnelmikroskopie (vgl. [2]) zeigt sich, das die Methode nicht nur eine sehr nutzliche Erweiterung des „Gerate-Zoos” der Oberflachenphysiker darstellt, sondern im Begriff ist, auch in Chemie und Biologie neue Einsichten in atomare und molekulare Mechanismen zu vermitteln. Im kreativen und kooperativen Klima, das in der Gemeinde der Tunnelmikroskopiker herrscht, entstand inzwischen eine Reihe interessanter technischer Erweiterungen, und in den drei letzten Jahren entwickelten sich aus dem RTM sogar neue eigenstandige Mikroskopieverfahren, wie die Kraftmikroskopie, die Thermoskopie und die optische und akustische Nahfeldmikroskopie. Uber einige jungere Ergebnisse und Weiterentwicklungen der Tunnelmikroskopie wird in diesem Artikel berichtet.

We review the present status of the singularity problem in gravitation theory. First we repeat the known results for Einstein's theory. After this, different other gravitation theories are considered under the following aspect: Which of the presumptions leading to singularities in Einstein's theory are not fulfilled, and can this prevent the singularities? In detail: scalar matter fields do not fulfil the positive energy condition, bimetric theories change the gravitational vacuum, theories with torsion and fourth order gravity add new geometric terms. It turns out that the answer is never simply no or yes, but requires new conditions, and new types of singularities occur. Otherwise there exist essential situations where the alternative theories satisfactorily prevent the singular behaviour known from Einstein's theory. Finally, we review on chaotic singularities.

Die Kohlenoxydverbindungen des Rheniums, die Halogenopentacarbonyle wie das reine dimere Pentacarbonyl, erweisen sich der CO-Substitution durch Pyridin oder o-Phenanthrolin zuganglich, wie dies schon fruher bei den Metallen der Eisen- und Chromgruppe aufgedeckt wurde. Die aminsubstituierten Rheniumcarbonyle enthalten samtlich noch wenigstens 3 Mol CO pro Rheniumatom, d.h.es werden stets nur 2Mol CO durch 2Mol Pyridin oder 1 Mol o-Phenanthrolin ersetzt: ReHal(CO)3Pyr2 nnd ReHal(CO)3 Phthrl sowie Re(CO)3Pyr2 und Re(CO)3, Phthrl2; letztere sind eventuell dimer wie das Rheniumpentacarbonyl. Die aminsubstituierten Rheniumcarbonyle erinnern bezuglich ihrer Entstehungsweise, ihres Baus und ihrer grosen Bestandigkeit durchaus an die aminsubstituierten Carbonyle der Chromgruppe.

The authors describe a technique which allows the direct transfer of the results of thin-layer chromatography or paper chromatography to preparative scale separations: a horizontal column is made using finely powdered adsorbents (silica gel, alumina, or cellulose powder) in a cellophane tube which can be cut into slices after development.

In a nuclear reactor, quartz alters gradually to an amorphous form. Some of the property changes observed are (a) decreases in density, refractive indices, rotatory power, and birefringence, (b) disappearance of the α-β transition, and (c) changes in the absorption spectrum. The properties of vitreous silica also alter in a nuclear reactor, the density and refractive index increasing somewhat. On heating the irradiated solids the properties alter in a complex manner.

Eine aus Brom und Natronlauge hergestellte Natriumhypobromitlosung wird zur Darstellung des Natriumbromits durch Disproportionierung benutzt. Das im Maximum der Bromitkonzentration vorhandene Hypobromit mus zerstort werden. Mit Bromwasser oder stickstoffverdunnten Bromdampfen kann bei niedrigen Temperaturen eine bromitfreie Hypobromitlosung hergestellt werden. Sodium bromite may be prepared by dismutation of hypobromite solution produced by the addition of bromine to concentrated caustic soda at 0 °C, the hypobromite being destroyed after the maximum bromite concentration has been reached. Using bromine water or bromine vapour diluted by nitrogen at low temperatures, it is possible to prepare bromite-free hypobromite solutions.

Nachdem die Bemuhungen, durch Hochdrucksynthese aus metallischem Rhenium oder durch weitere Reaktionen der Halogenopentacarbonyle reines Rheniumcarbonyl zu erhalten, unter verschiedensten Bedingungen erfolglos blieben, wurde gefunden, das oxydische Rheniumverbindungen, insbesondere Re2O7 oder auch ReO4K u. a. unter hoherem CO-Druck und bei hoherer Temperatur direkt halogenfreies, reines Rheniumcarbonyl liefern. Uber den Reaktionsmechanismus der einfach zu formulierenden Umsetzungen werden verschiedene Vorstellungen entwickelt.

The age, rate of growth, reproduction, feeding habits, and population dynamics of the emerald shiner (Notropis atherinoides) were studied from 10,375 fish collected in Lewis and Clark Lake, South Dakota. The population in this 28,000-acre reservoir consisted of four age groups dominated by young-of-the-year during the summer and fall and by age-group I during the spring and early summer. Age-group II was common only in the spring and early summer while age-group III was rarely encountered. Average lengths at first and second annulus formations were 66 and 84 mm. Females attained larger sizes than males after the first year. The spawning season extended from June through August. A rapid and precise method was devised for conducting food-habit determinations that could be analyzed statistically. Adult emerald shiners fed selectively on large zooplankton. A gradual change in young-of-the-year food habits was evident; fish smaller than 40 mm fed primarily on algae, whereas larger fish fed chiefly on ...