Thermal Processes During Mechanical Treatment of ZnO and ZnO-TiO2 Powders and their Role in the Formation of Defect Structure

We used electron paramagnetic resonance (EPR) to determine the dependence of the defect structure of zinc oxide powders on the physical characteristics of admixed particles during prolonged mechanical treatment (MT). Our results demonstrate a sequential two-stage thermal process contributing to the defect structure during MT. In the first stage of MT a collective break-up process of individual ZnO particles occurs and the defects are caused by hyper-rapid thermal defects annealing (HRTDA) of the particles. The second stage of defect formation is associated with annealing effects caused by heat accumulation.     

Vorstellung eines neuartigen Brenners zur Erzeugung von turbulenten, verdrallten Kohlenwasserstoff – Diffusionsflammen

Technische industrielle Verbrennung ist meistens turbulente Verbrennung von Kohlenwasserstoffen in Diffusionsflammen. Die Grundlagenforschung auf diesem Gebiet basiert auf den drei Säulen physikalische Modellierung, numerische Simulationen und Validierung durch Experimente meistens mittels Laserdiagnostik. Es gibt eine lange Historie über die Konstruktion und den Bau von geeigneten Brennern, mit denen turbulente Kohlenwasserstoff Diffusionsflammen erzeugt werden können, die sowohl simuliert als auch vermessen werden können. Von diesen beiden Methoden ausgehend gibt es eine Reihe von Restriktionen bezüglich des endgültigen Designs des Brenners und der Flammen, die untersucht werden sollen. Ein kritischer Aspekt sind dabei die lokalen Ruß- und PAH- Konzentrationen in den Flammen, weil alle spektroskopischen Messtechniken, die für Konzentrationsmessungen verwendet werden müssen, durch Ruß und PAH stark gestört werden. Mit den meisten Brennern, die man bis jetzt verwendet hat, hat man versucht, dieses Problem mit mehr oder weniger Erfolg und mit mehr oder weniger Nachteilen bezüglich anderer Aspekte zu überwinden, indem man Kompromisse einging. Wir haben einen neuartigen Brenner entwickelt, der einige dabei auftretenden Probleme löst und den wir als neuen Testfallbrenner vorschlagen. Mit diesem Brenner werden verdrallte turbulente Diffusionsflammen mit sehr wenig lokalen Ruß- und PAH -Konzentrationen geschaffen. Bis jetzt wurde Methan als Brennstoff verwendet. Die Vor- und Nachteile des Brenners und der Flammen werden in diesem Artikel detailliert diskutiert. Weiterhin werden erste Ergebnisse vorgestellt. Mehr Informationen zu diesen Arbeiten sind zu finden unter: http://www. ltt-rostock.de/text/tmd_vbfltt.htm.Technical and industrial combustion is mostly turbulent diffusion combustion with hydrocarbon fuels. Fundamental research on this field is based on three columns, physical modeling, numerical simulations and validation experiments mostly done by laser diagnostics. There is a long tradition in constructing and building burners that will create turbulent hydrocarbon diffusion flames which can be both, simulated and measured. From these both methods result a number of different requirements for the final design of burner and flames to be investigated. One critical aspect is local soot and PAH concentration within the flames due to the fact, that spectroscopic measurement techniques which have to be used for concentration determination are strongly hampered by soot or PAHs. With most of the burners used so far it has been tried to overcome this problem with more or less success and with more or less disadvantages on other aspects as they tried to make a trade-off. We have developed a new kind of burner which will overcome some problems and which we propose as a new test case burner. It creates swirling turbulent diffusion hydrocarbon flames with very low level of local soot or PAHs. So far we used methane as fuel. The advantages and disadvantages of the burner and flames are discussed in detail within this paper. First results are also reported, more information about this work can be found under http://www.ltt-rostock.de/text/tmd_vbfltt.htm.

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Determination of pre-impact occupant postures and analysis of consequences on injury outcome. Part I: a driving simulator study

This paper considers pre-impact vehicle maneuvers and analyzes the resulting driver motion from their comfort seating position. Part I of this work consists of analyzing the driver behavior during a crash. The study is conducted using the LAMIH driving simulator and involves 76 participants. The emergency situation is created by a truck emerging from behind a tractor on the opposite side of the road and tearing along the participant. The driver positioning throughout the simulation is recorded via five video cameras allowing view of the front scene, the driver face, feet and pedals, hands on the steering wheel and global lateral view. Data related to braking force, seat pressure, muscular activity for major groups of muscles and actions on the steering wheel are also collected.The typical response to this type of emergency event is to brace rearward into the seat and to straighten the arms against the steering wheel, or, to swerve to attempt to avoid the impacting vehicle. While turning the steering wheel, the forearm can be directly positioned on the airbag module at time of crash which represents a potential injurious situation.These positions are used in Part II to determine scenario of positions for numerical simulation of a frontal collision.     

Single- and Multiscale Laser Patterning of 3D Printed Biomedical Titanium Alloy: Toward an Enhanced Adhesion and Early Differentiation of Human Bone Marrow Stromal Cells

This study explores the enhancement of biocompatible titanium-based implants through surface functionalization for improved bone healing. Specifically, a near-beta type Ti-13Nb-13Zr alloy is 3D printed using laser powder bed fusion and subsequently textured using nanosecond (ns) and picosecond (ps) direct laser interference patterning (DLIP) to create single-scale and multi-scale surface textures. On these textures, the cell behavior, morphology, metabolic activity and osteogenic differentiation potential of human bone marrow stromal cells are assessed using fluorescence microscopy and MTS assays. Moreover, tissue non-specific alkaline phosphatase activity served as an early osteoblast production marker. Compared to untextured specimens, both types of textures exhibited higher metabolic activity and cell proliferation. Single-scale ns-DLIP textures encouraged cell extensions anchored in groove regions, while ps-DLIP textures with hierarchical structures promoted cell extensions attaching to nanostructures on sidewalls. The groove width and nanotopographies in groove areas facilitated cell spreading. Surface topography, roughness, and surface chemistry (surface energy, wettability) influenced cell adhesion, proliferation, and differentiation. A comprehensive evaluation of DLIP-generated surface textures, including their topography and chemical states, complements the factors affecting in vitro cell behavior. Overall, this research demonstrates the potential of surface-functionalized 3Dprinted titanium for a novel generation of biocompatible implants.     

Sensor fault reconstruction and observability for unknown inputs,with an application to wastewater treatment plants

In this article, we propose a general methodology for identifying and reconstructing sensor faults on dynamical processes. This methodology is issued from the general identification theory developed in the previous papers (Busvelle, E., and Gauthier, J.-P. (2003), ‘On Determining Unknown Functions in Differential Systems, with an Application to Biological Reactor’, ESAIM: Control, Optimisation and Calculus of Variations, 9, 509–553; Busvelle, E., and Gauthier, J.-P. (2004), ‘New Results on Identifiability of Nonlinear Systems’, in 2nd Symposium on Systems, Structure and Control, Oaxaca, Mexico; Busvelle, E., and Gauthier, J.-P. (2005), ‘Observation and Identification Tools for Non Linear Systems. Application to a Fluid Catalytic Cracker’, International Journal of Control, 78, 208–234): in fact, this identification theory also provides a general framework for the problem of ‘observability with unknown inputs’. Indeed, many problems of fault detection can be formulated as such observability problems, the (eventually additive) faults being just considered as unknown inputs. Our application to ‘sensor fault detection’ for wastewater treatment plants (WWTP) constitutes an ideal academic context to apply the theory: first, in this 3-5 case (3 sensors, 5 states), the theory applies generically and, second, any system is naturally under the ‘observability canonical form’ required to apply the basic high-gain observer from Gauthier and Kupka (Gauthier, J.-P., and Kupka, I. (1994), ‘Observability and Observers for Nonlinear Systems’, SIAM Journal on Control, 32, 975–994). A simulation study on the Bleesbrük WWTP is proposed to show the effectiveness of this approach.     

Local and relational aspects of face distinctiveness

Distinctiveness contributes strongly to the recognition and rejection of faces in memory tasks. In four experiments we examine the role played by local and relational information in the distinctiveness of upright and inverted faces. In all experiments subjects saw one of three versions of a face: original faces, which had been rated as average in distinctiveness in a previous study (Hancock, Burton, & Bruce, 1996), a more distinctive version in which local features had been changed (D-local), and a more distinctive version in which relational features had been changed (D-rel). An increase in distinctiveness was found for D-local and D-rel faces in Experiment 1 (complete faces) and 3 and 4 (face internals only) when the faces had to be rated in upright presentation, but the distinctiveness of the D-rel faces was reduced much more than that of the D-local versions when the ratings were given to the faces presented upside-down (Experiments 1 and 3). Recognition performance showed a similar pattern: presented upright, both D-local and D-rel revealed higher performance compared to the originals, but in upside-down presentation the D-local versions showed a much stronger distinctiveness advantage. When only internal features of faces were used (Experiments 3 and 4), the D-rel faces lost their advantage over the Original versions in inverted presentation. The results suggest that at least two dimensions of facial information contribute to a face's apparent distinctiveness, but that these sources of information are differentially affected by turning the face upside-down. These findings are in accordance with a face processing model in which face inversion effects occur because a specific type of information processing is disrupted, rather than because of a general disruption of performance.     

Transposon-generated 'knock-out' and 'knock-in' gene-targeting constructs for use in mice

The conventional technique for targeted mutation of mouse genes entails placing a genomic DNA fragment containing the gene of interest into a vector for fine mapping, followed by cloning of two genomic arms around a selectable neomycin-resistance cassette in a vector containing thymidine kinase [1]; this generally requires 1-2 months of work for each construct. The single 'knock-out' construct is then transfected into mouse embryonic stem (ES) cells, which are subsequently subjected to positive selection (using G418 to select for neomycin-resistance) and negative selection (using FIAU to exclude cells lacking thymidine kinase), allowing the selection of cells which have undergone homologous recombination with the knockout vector. This approach leads to inactivation of the gene of interest [2]. Recently, an in vitro reaction was developed, on the basis of the yeast Ty transposon, as a useful technique in shotgun sequencing [3]. An artificial transposable element, integrase enzyme and the target plasmid are incubated together to engender transposition. The DNA is then purified, and subsequently electroporated into bacteria. The transposon and the target plasmid bear distinct antibiotic resistance markers (trimethoprim and ampicillin, respectively), allowing double selection for transposition events. In the present study, we have modified this system to allow the rapid, simultaneous generation of a palette of potential gene targeting constructs. Our approach led from genomic clone to completed construct ready for transfection in a matter of days. The results presented here indicate that this technique should also be applicable to the generation of gene fusion constructs [4-8], simplifying this technically demanding method.     

Gastric versus duodenal feeding and gastric tonometric measurements

OBJECTIVE: To compare the influence of gastric and postpyloric enteral feeding on the gastric tonometric PCO2 gap (tonometric PCO2 - PaCO2). DESIGN: A prospective, clinical trial. SETTING: Two intensive care units in a university hospital. PATIENTS: Twenty patients undergoing mechanical ventilation and enteral feeding without catecholamines, sepsis, or sign of hypoxia. INTERVENTIONS: Patients were randomized to receive feeding through the tonometer (gastric group), or through a postpyloric tube (postpyloric group). MEASUREMENTS AND MAIN RESULTS: The patients received tube feeding at a rate of 50 mL/hr during 4 hrs. Baseline measurements included: mean arterial pressure, heart rate, tonometric parameters, arterial gases, and arterial lactate concentration. Except for lactate concentration, these measurements were repeated after 1 and 4 hrs of enteral feeding and 2 hrs after stopping enteral feeding. During the study, arterial pH and PaCO2 did not change. During enteral feeding, the PCO2 gap increased in the gastric group from a mean of 7+/-5 to 17+/-14 (SD) torr (0.9 0.7 to 2.3+/-1.9 kPa) (p< .O01) and did not change in the postpyloric group (5+/-5 to 3+/-1 torr [0.7+/-0.7 to 0.4+/-0.1 kPa]). Two hours after stopping enteral feeding, the PCO2 gap was still increased in the gastric group (15+/-9 vs. 7+/-5 torr [2.0+/-1.2 vs. 0.9+/-0.7 kPa]) (p < .01). CONCLUSION: The results indicate that gastric enteral feeding increased the PCO2 gap. However, postpyloric enteral feeding does not interact with gastric tonometric measurements and should be used when using gastric tonometry in enterally fed patients.     

Sex and locus of control as determinants of children's responses to peer versus adult praise.

Gave 80 Black 1st graders varying in internal–external control (as identified by scores on the Stanford Preschool Internal–External Scale) a series of digit substitution problems during which their performance was praised by either a Black boy and girl or a Black man and woman ostensibly watching them from another room. Agents' feedback was previously videotaped. As predicted, boys were most responsive to peer feedback and girls were most responsive to adult feedback, as revealed by faster problem-solving rates on reinforced tasks, higher scores on a related substitution task, and greater attributions of agent helpfulness. Predictions involving locus of control received only modest support. The relationship of these results to earlier studies involving dissimilar populations is discussed and educational implications are drawn. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generalizability of locus of control: A Rep Grid investigation of personality consistency.

Developed 2 measures based on G. A. Kelly's Rep Grid Test, one dealing with personal events and the other with general societal events. Results from 258 undergraduates show that internals used significantly more internal constructs than did externals and that Ss chose more internal constructs on the personal than on the societal measure. Results suggest that the internal-external dichotomy is reflected in and may be mediated by modes of thinking and categorization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)