Virtual reality for the psychophysiological assessment of phobic fear: Responses during virtual tunnel driving.

An overall assessment of phobic fear requires not only a verbal self-report of fear but also an assessment of behavioral and physiological responses. Virtual reality can be used to simulate realistic (phobic) situations and therefore should be useful for inducing emotions in a controlled, standardized way. Verbal and physiological fear reactions were examined in 15 highly tunnel-fearful and 15 matched control participants in 3 virtual driving scenarios: an open environment, a partially open tunnel (gallery), and a closed tunnel. Highly tunnel-fearful participants were characterized by elevated fear responses specifically during tunnel drives as reflected in verbal fear ratings, heart rate reactions, and startle responses. Heart rate and fear ratings differentiated highly tunnel-fearful from control participants with an accuracy of 88% and 93%, respectively. Results indicate that virtual environments are valuable tools for the assessment of fear reactions and should be used in future experimental research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Minimization of the Intermodulation Distortion of a Nonlinearly Amplified OFDM Signal

In the course of development of the HIPERLAN-Standard OFDM (Orthogonal Frequency Division Multiplexing) was a possible candidate for the modulation scheme.An advantage of OFDM is that it can be implemented simply and that it is suitable for the transmission of high data rates in the mobile radio channel. Furthermore, it is insensitive against disturbances caused by multipath propagation. However, the OFDM signal shows a nonconstant envelope that leads to unwanted out-of-band radiation, in case the transmitter amplifier has a nonlinear characteristic.In this paper a method for the reduction of the fluctuation of the envelope of an OFDM signal is presented. Combined with a predistortion to linearize the characteristic of the transmitter amplifier an efficient method for the reduction of the out-of-band radiation results so that OFDM could prove to be a suitable modulation scheme for future mobile telecommunication applications.     

Real-time simulation of heat transfer in continuous casting

A real-time heat-transfer model for continuous slab casting is presented. The model calculates the strand temperatures and the solid shell thickness profile along the machine as a function of the actual casting variables, strand geometry, and steel grade. The special requirements con-cerning the real-time use of the model and, in general, the accuracy of the model are also studied and discussed. The model has been tested by carrying out industrial trials. Some examples of the differences between the calculated and measured surface temperatures are presented. A spe-cial procedure to determine the boundary conditions for the secondary cooling zones from tem-perature measurements is also described.     

Targeting the Water Network in Cyclin G-Associated Kinase (GAK) with 4-Anilino-quin(az)oline Inhibitors

Water networks within kinase inhibitor design and more widely within drug discovery are generally poorly understood. The successful targeting of these networks prospectively has great promise for all facets of inhibitor design, including potency and selectivity for the target. Herein, we describe the design and testing of a targeted library of 4-anilinoquin(az)olines for use as inhibitors of cyclin G-associated kinase (GAK). GAK cellular target engagement assays, ATP binding-site modelling and extensive water mapping provide a clear route to access potent inhibitors for GAK and beyond.     

Bone morphogenetic protein 15 and growth differentiation factor 9 co-operate to regulate granulosa cell function

The oocyte-secreted polypeptide growth factors, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15, also known as GDF9B) have both been shown to be essential for ovarian follicular growth and function. The effects of murine (m) and ovine (o) GDF9 as well as oBMP15, alone or together, on 3H-thymidine uptake and progesterone and inhibin production by granulosa cells from rats were determined. Murine GDF9 stimulated thymidine incorporation by granulosa cells whereas oGDF9 and oBMP15 alone had no effect. However, oBMP15 given together with mGDF9 or oGDF9 was very potent in stimulating 3H-thymidine incorporation by granulosa cells with a greater than 3-fold stimulation compared with any growth factor alone. The synergistic effect of oBMP15 and oGDF9 was almost completely blocked by antibodies generated against these growth factors when administered either alone or in combination. While neither GDF9 (murine or ovine) nor oBMP15 were able to modulate FSH-stimulated progesterone production on their own, FSH-stimulated progesterone production by granulosa cells was potently inhibited when BMP15 and GDF9 were administered together. Immunoreactive alpha-inhibin levels increased more than 15-fold from granulosa cells when BMP15 and GDF9 were given together whereas consistent stimulatory effects of either growth factor alone were not observed. The effects of GDF9 and BMP15, when added together, were different than those observed for the growth factors alone. Therefore, we hypothesize that within the ovary, these oocyte-secreted growth factors co-operate to regulate proliferation and gonadotropin-induced differentiation of granulosa cells in mammals.     

Bone morphogenetic protein 15 and growth differentiation factor 9 co-operate to regulate granulosa cell function in ruminants

The oocyte-secreted polypeptide growth factors, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15, also known as GDF9B) have both been shown to be essential for ovarian follicular development and ovulation rate. In addition, it is known from both in vivo and in vitro studies that these factors co-operate in some manner. To date, most studies examining the in vitro effects of these growth factors have used the rodent model. However, the evidence suggests that these growth factors have somewhat different roles between rodents and ruminants. Therefore, the objectives of these studies were to examine the effects of GDF9 and BMP15, alone and together, on the functions of ovine and bovine granulosa cells under in vitro conditions. Ovine (o)BMP15 given together with murine (m)GDF9 or oGDF9 was more potent in stimulating (3)H-thymidine incorporation by ovine granulosa cells compared with each growth factor alone. For bovine granulosa cells, there appeared to be little or no co-operativity between oBMP15 and oGDF9 as oBMP15 alone was as potent as any combination of the two growth factors in stimulating (3)H-thymidine uptake. The species of origin of GDF9 affected the progesterone response in ovine granulosa cells with mGDF9 stimulating and oGDF9 inhibiting progesterone production. Ovine BMP15 alone had no effect on progesterone production by ovine granulosa cells and these growth factors did not appear to co-operate. FSH-stimulated progesterone production by bovine granulosa cells was most potently inhibited when oBMP15 and murine or ovine GDF9 were administered together. As was observed for progesterone, the species of origin of GDF9 affected inhibin production by ovine granulosa cells where mGDF9 inhibited while oGDF9 stimulated production. Murine GDF9 also inhibited inhibin production from bovine granulosa cells. For both ovine and bovine granulosa cells, BMP15 alone had no effect on inhibin production and there did not appear to be any co-operation between GDF9 and BMP15. These results indicate that the effects of BMP15 and GDF9 varied with respect to the species of origin of the growth factor. Moreover, the effects of GDF9 and BMP15 together were often co-operative and not always the same as those observed for these growth factors alone.     

SEM–EDS characterization of inorganic material in refuse-derived fuels

The utilisation of refuse-derived fuel (RDF) in energy production is restricted by their inorganic impurities, such as heavy metals and chlorine. In this contribution, three different types of RDF were studied by SEM–EDS. These materials originated from three locations: construction sites, households, and supermarkets. Several fuel samples of every type of RDF were used in this study. The compositional distributions of the inorganic particles were determined directly from each fuel and the results are presented as quasiternary diagrams. The presentation method makes it possible to identify inorganic particles such as sand, alkali metal chlorides, calcium chloride, gypsum, lime, titanium pigment, iron as an element or oxide, and metallic aluminium from fuel. The results can be used to discuss the origin of different inorganic components in these materials and serve as a base for discussion of the suitability to use each waste material as fuel. It also facilitates the design of appropriate purification steps that are needed.     

Induction of IgG in young nude mice by lipid A or thymus grafts

Postnatal serum concentrations of IgG2a of paternal allotype, measured in congenitally thymusless nude mice, increase with kinetics and titers comparable to their normal congeneic counterparts. Lipid A, the mitogenic part of LPS, stimulates IgG synthesis in nude mice when it is given 7 days after birth. IgG concentrations at 15 days of age are 6- to 8-fold higher than in untreated control nudes; this is considerably lower, however, than in normal mice, which show up to 45-fold higher IgG2ab levels after lipid A treatment. A thymus graft from nearly congeneic donors of the same age, transplanted at 4 days after birth, also stimulates long-lasting IgG synthesis in the nude recipients. If the grafted nudes are injected with lipid A 3 days later, IgG synthesis is further stimulated 8- to 16-fold. The data are discussed in relation to the thymus dependency of IgG production and the conditions for lipid A stimulation.     

On the optimal layout of multi-purpose trusses

This paper provides a solution to the problem of minimum mass design of multi-purpose trusses for which the design variables are not only the areas of the bars but also the positions of the joints. Displacement constraints and non-constant stress constraints (stability) are taken into account.

With multiple loading systems, the optimal structure is normally statically indeterminate and generally not even ·fully stressed”. The solution is obtained by successive iterations, using a gradient method with move-limits. For each iteration only the critical forces and displacements are considered and trusses with up to 40 joints have been optimized.

Analytical expressions are derived for the necessary gradients, i.e. for the partial derivatives of the displacements and forces with respect to the bar areas and joint coordinates.     

Low‐alloyed TRIP‐Steels with Optimized Strength,Forming and Welding Properties

To obtain the superior strength‐ductility‐balance of TRIP‐grades, a special chemical composition in combination with well adapted processing parameters are a prerequisite. Despite of their excellent formability performance in terms of drawability as characterized by high n‐ and elongation values, compared to mild steels TRIP‐grades are challenging in the press and the body shops. The high strength level in combination with the high work hardening of TRIP‐grades result in higher levels of spring back compared to mild steels and higher press forces are required. Furthermore, a higher sensitivity to failure for sharp bending radii and a deterioration of the formability of punched edges is reported for TRIP‐grades. While spring back can only be minimized by advanced forming processes supported by new simulation techniques with improved ability to predict spring back, the sensitivity to failure under special forming conditions can be influenced by optimizing microstructural features. Contrary to the forming behaviour, which is influenced significantly by the microstructure, the weldability is mainly governed by the chemical composition and the surface condition of the material. The high carbon content of TRIP‐grades compared to mild steels results in a higher hardening potential after welding. Additionally, a fracture behaviour untypical for mild steels after destructive testing of spot welds is sometimes observed for TRIP‐grades, which is assessed critically by some OEMs. In this work, after a discussion of the processing conditions, possibilities are demonstrated to improve the forming behaviour by an optimization of the microstructure and the spot weldability by adapting the chemical composition of low‐alloyed TRIP grades. First very promising results for TRIP‐grades with a minimum tensile strength level of 700 MPa are discussed.