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Functional magnetic resonance imaging (fMRI) studies in schizophrenia found altered brain activation patterns during Theory of Mind (ToM) task performance in the so-called ToM-network, recently focusing on over- rather than under-activation. Even though most fMRI-studies applied tasks that might gradually activate the ToM-network, no study so far has investigated the time-course of ToM-performance. Some of the varying activation results might thus be due to time-course of performance.
Our aim was to investigate neural activation over time in schizophrenia compared with a healthy control sample.
Using a block design in fMRI, we presented a sophisticated paradigm that depicts moving geometrical shapes interacting in social patterns. 14 patients with schizophrenia and 15 healthy controls participated in the study. Functional activation patterns were investigated for the first and second half of the videos separately.
Both groups activated brain areas related to the ToM-network during performance of ToM videos as compared to a baseline condition. Most importanly, schizophrenia patients showed activation in ToM-related brain areas only in the second part, while healthy controls activated the ToM-network in the first part of the video presentation.
Results confirm recent findings of an increased activation in ToM-related brain areas in schizophrenia. Moreover, patients activated ToM-related brain areas later than healthy controls. This delay might be due to a general cognitive slowing, symptom-related inhibition of cognition-associated processes or specific delay in task processing. As this is the first study to investigate this time-course of ToM, more research is needed to classify results.
This case of a 65-year-old male with dermatillomania, diffuse anxiety symptoms, and avoidant personality disorder (PD) illustrates the interference of attention-deficit hyperactivity disorder (ADHD) in the diagnostic process and during schema-focused therapy. In conclusion, ADHD in older adults and interference with PD is a subject of clinical importance and worth further investigation.
The structure of crystals can be described by defining size and shape of a unit cell and the positions of the atoms within it. Many materials, however, exhibit a glassy or amorphous structure. Such disordered structures are described by structure factors. These are usually determined by small angle scattering experiments. The angular distribution recorded in these experiments is related to the structure factor. In this work we present an alternative approach using elemental maps obtained in an energy filtering transmission electron microscope. In this way we can even obtain chemically resolved partial structure factors giving additional information on the specimen.
The gastrointestinal tract is a complex milieu as a result of interaction between dietary ingredients and the intestinal bacteria. Following the European ban on the use of in-feed antibiotics, research has focused mainly on the potentially beneficial activities of the intestinal microbiota. Fermentable carbohydrates, or ‘prebiotics’, such as non-digestible oligosaccharides, are considered to have beneficial effects on the composition and activity of the indigenous microbiota, which can enhance the resistance of the host against colonisation of pathogenic bacteria in the GIT. Only a limited number of prebiotics has been tested in broilers that include fructo-oligosaccharides, inulin, mannan-oligosaccharides, alpha gluco-oligosaccharides, isomalto-oligosaccharides, different kestoses and lactose along with its derivatives. This review provides an overview pertaining to the potential impact of prebiotics on the intestinal bacterial population in broilers and summarizes the data regarding the role of prebiotics in preventing the colonisation of enteropathogens especially Salmonella spp., Campylobacter spp. and Clostridium spp. Moreover, the influence of prebiotics on the intestinal bacterial fermentation profile, particularly short chain fatty acids, ammonia and lactate, is also discussed. Prebiotics have been found to affect the intestinal bacterial population particularly elevating the caecal count of Lactobacillus spp. and Bifidobacterium spp. The effect of prebiotics on the intestinal bacteria is also evident in terms of change in the total concentration or relative proportion of short chain fatty acids. The ability of prebiotics in controlling the colonisation of different enterpathogens especially Salmonella spp., Clostridium perfringens or Campylobacter spp. showed inconsistent results depending upon the available literature.
Two series of Ni-Mn-Ga thin films with two different compositions and various thicknesses in the submicron range are investigated with respect to their structural and magnetic properties. The films are fabricated by sputter deposition on alumina substrates and subsequent heat treatment. The martensitic transformation occurs well above room temperature showing a small thermal hysteresis width of about 6 K. The magnetic properties turn out to be thickness-dependent in the submicron range. In particular, in-plane magnetic susceptibilities increase and critical field strengths for onset of saturation decrease for decreasing thickness down to 0.1 μm by factors of 3–5 depending on the chemical composition. The Curie temperature TC decreases by about 25 K for samples with TC higher than the martensitic transformation.
The dynamics of competitive colonisation of necrotic cyclamen tissue by the plant pathogenic fungus Botrytis cinerea and the saprophytic fungal antagonist Ulocladium atrum were studied immuno-histologically, while sporulation was studied macroscopically. The effect of different time intervals between inoculation of both fungi on resource capture by each species was explored. Colonisation and sporulation were used as indicators for competitive resource capture and the effectiveness of biological control of B. cinerea, using U. atrum. Mycelial biomass and sporulation showed logistical time courses in both species, in monocultures as well as in mixed cultures. Final colonisation and sporulation levels were lowered by competition, indicating competitive resource capture. Analysis of the extent to which sporulation of either fungus could be reduced by co-inoculation with the other fungus at different times, showed that B. cinerea can be completely excluded by ‘early’ pre-inoculation with U. atrum, but not vice versa, indicating that U. atrum can exploit resources in the leaf that are not accessible to B. cinerea. A model of competitive substrate colonisation and resource capture was developed on the basis of the experimental results. Model results confirm that competition for resources provides a sufficient biological explanation for the dynamic interactions between the fungi. The model provides a tool to optimise dose and timing of U. atrum applications providing effective biological control of B. cinerea.
This paper describes the first industrial application of the new DYNAFLEX oscillator developed by VAI
on the two billet casting machines at Lech-Stahlwerke (Germany). Its main features are : no
servohydraulic components, a system of leaf-springs arranged in cascade, simplicity of adjustment of
stroke, frequency and wave form during casting. These factors suppress the need for maintenance of
the oscillator, prevent mechanical backlash and result in a significant increase in machine availability
and product quality, as well as in reduced maintenance costs.
Carbon coated silica made by flame synthesis was investigated for reinforcement of styrene-butadiene (SBR) rubber. These composite silica/carbon fillers were examined through small angle x-ray scattering (SAXS), TEM, and AFM showing that these fillers have a rough fractal surface and have fractal aggregate structures. The carbon coated silica fillers were compounded with elastomers and their effect on reinforcement was measured using dynamic mechanical analysis and tensile testing. These fillers were also compared to commercial fumed silica, carbon black, and carbon black/silica composite fillers.
Three stands of Phragmites australis (Cav.) Trin. ex Steudel
were investigated regarding the relationship between
the number of efflux culms and convective ventilation efficiency affecting
the hypoxic status of roots and rhizomes.
The lack of old (efflux) culms after mowing the preceding winter caused
a significantly higher counterpressure
within the rhizome, thereby diminishing air flushing rate, i.e. oxygen
supply, of rhizomes. The levels of alanine
and c-aminobutyric acid in basal culm internodes increased significantly.
Both amino acids indicate the hypoxic
status of the root and rhizome metabolism of P. australis. Amino
acid patterns of the basal culm internodes are
discussed with respect to the maintenance of aerobic root metabolism and
Nitrate contamination of surface water resulting from inputs of agricultural drainage water is a widespread problem. To learn whether alternative agricultural practices might ameliorate this problem, we measured NO-3 in water draining from three neighboring fields from 1970 to 1992. Drainage water from two fields fertilized with N exclusively as composted and liquid manure had NO-3 concentrations less than 2 ppm (20% of the Public Health Service recommended limit for drinking water). When these fields were converted to a corn/soybean rotation fertilized with anhydrous ammonia, NO-3 concentration increased about 7- to 10-fold. On a third field, corn was always fertilized with anhydrous ammonia. Changing this field from a rotation of corn, oats and hay to corn/soybean and increasing the rate of N fertilization by about 18% almost doubled the NO-3 concentration in the drainage water. The corn/soybean rotation most prevalent in the Corn Belt today resulted in high NO-3 concentrations in the drainage water, while the alternative system prevented NO-3 problems.
There is considerable interest in insulators with static dielectric constants lower than SiO2; an alloy system attracting recent attention is Si-O-F. Alloying of F atoms into plasma-deposited SiO2 films leads to major changes in the SiO2 bond-stretching and -bending infrared bands accounting for a significant fraction of the reduction in the dielectric constant. These changes are explained by F induced modifications of force constants and effective charges of the neighboring Si-O-Si groups.
A novel polymer has been developed for use as a thin film dielectric in the interconnect structure of high density integrated circuits. The coating is applied to the substrate as an oligomeric solution, SiLK*, using conventional spin coating equipment and produces highly uniform films after curing at 400 °C to 450 °C. The oligomeric solution, with a viscosity of ca. 30 cPs, is readily handled on standard thin film coating equipment. Polymerization does not require a catalyst. There is no water evolved during the polymerization. The resulting polymer network is an aromatic hydrocarbon with an isotropie structure and contains no fluorine.
The properties of the cured films are designed to permit integration with current ILD processes. In particular, the rate of weight-loss during isothermal exposures at 450 °C is ca. 0.7 wt.%/hour. The dielectric constant of cured SiLK has been measured at 2.65. The refractive index in both the in-plane and out-of-plane directions is 1.63. The flow characteristics of SiLK lead to broad topographic planarization and permit the filling of gaps at least as narrow as 0.1 μm. The glass transition temperature for the fully cured film is greater than 490 °C. The coefficient of thermal expansivity is 66 ppm/°C below the glass transition temperature. The stress in fully cured films on Si wafers is ca. 60 MPa at room temperature. The fracture toughness measured on thin films is 0.62 MPa m ½. Thin coatings absorb less than 0.25 wt.% water when exposed to 80% relative humidity at room temperature.
Using Si and GaAs substrates, the coefficient of thermal expansion (CTE) and the bi-axial modulus of thin hydrogen silsesquioxanes (HSQ) films are deduced by means of wafer curvature measurement. The same properties of plasma-enhanced CVD oxide are also reported.
Interactions between fluorinated polyimide and aluminum under different thermal treatment conditions have been investigated using transmission electron microscopy (TEM) and x-ray diffractometry (XRD) techniques over a wide temperature range. Our results suggest that the oxygen from the dielectric materials may result in the oxidation of the underlying aluminum either on the surface or along the grain boundary. This work implies that processing conditions, such as curing temperature and time, may play critical roles in affecting the performance of polymeric dielectric materials.