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The enzyme diisopropyl fluorophosphatase (DFPase) from the squid Loligo vulgaris is of great interest because of its ability to catalyze the hydrolysis of highly toxic organophosphates. In this work, the enzyme structure in solution (native state) was studied by use of different scattering methods. The results are compared with those from hydrodynamic model calculations based on the DFPase crystal structure. Bicontinuous microemulsions made of sugar surfactants are discussed as host systems for the DFPase. The microemulsion remains stable in the presence of the enzyme, which is shown by means of scattering experiments. Moreover, activity assays reveal that the DFPase still has high activity in this complex reaction medium. To complement the scattering experiments cryo-SEM was also employed to study the microemulsion structure.
We define the Dirichlet to Neumann operator for an elliptic complex of first order differential operators on a compact Riemannian manifold with boundary. Under reasonable conditions the Betti numbers of the complex prove to be completely determined by the Dirichlet to Neumann operator on the boundary.
The formation of secondary Ln(III) solid phases (e.g. Nd(OH)CO3 and Sm(OH)CO3) has been studied as a function of the humic acid (HA) concentration in 0.1 M NaClO4 aqueous solution and their solubility has been investigated in the neutral pH range (6.5-8) under normal atmospheric conditions. Nd(III) and Sm(III) were selected as analogues for trivalent lanthanide and actinide ions. The solid phases under investigation have been prepared by alkaline precipitation and characterized by TGA, ATR-FTIR, XRD, TRLFS, DR-UV-Vis and Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicate that Nd(OH)CO3 and Sm(OH)CO3 are stable and remain the solubility limiting solid phases even in the presence of increased HA concentration (0.5 g/L) in solution. Upon base addition in the Ln(III)-HA system decomplexation of the previously formed Ln(III)-humate complexes and precipitation of two distinct phases occurs, the inorganic (Ln(OH)CO3) and the organic phase (HA), which is adsorbed on the particle surface of the former. Nevertheless, HA affects the particle size of the solid phases. Increasing HA concentration results in decreasing crystallite size of the Nd(OH)CO3 and increasing crystallite size of the Sm(OH)CO3 solid phase, and affects inversely the solubility of the solid phases. However, this impact on the solid phase properties is expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.
Most studies investigating the impact of literacy on oral language processing have shown that literacy provides phonological awareness skills in the processing of oral language. The implications of these results on aphasia tests could be significant and pose questions on the adequacy of such tools for testing non-literate individuals. Aiming at examining the impact of literacy on oral language processing and its implication on aphasia tests, this study tested 12 non-literate and 12 literate individuals with a modified Amharic version of the Bilingual Aphasia Test (Paradis and Amberber, 1991, Bilingual Aphasia Test. Amharic version. Hillsdale, NJ: Lawrence Erlbaum.). The problems of phonological awareness skills in oral language processing in non-literates are substantiated. In addition, compared with literate participants, non-literate individuals demonstrated difficulties in the word/sentence-picture matching tasks. This study has also revealed that the Amharic version of the Bilingual Aphasia Test may be viable for testing Amharic-speaking non-literate individuals with aphasia when modifications are incorporated.
The heterogeneity in species assemblages of epigeal spiders was studied in a natural forest and in a managed forest. Additionally the effects of small-scale microhabitat heterogeneity of managed and unmanaged forests were determined by analysing the spider assemblages of three different microhabitat structures (i. vegetation, ii. dead wood. iii. litter cover). The spider were collected in a block design by pitfall traps (n=72) in a 4-week interval. To reveal key environmental factors affecting the spider distribution abiotic and biotic habitat parameters (e.g. vegetation parameters, climate parameters, soil moisture) were assessed around each pitfall trap. A TWINSPAN analyses separated pitfall traps from the natural forest from traps of the managed forest. A subsequent discriminant analyses revealed that the temperature, the visible sky, the plant diversity and the mean diameter at breast height as key discriminant factors between the microhabitat groupings designated by the TWINSPAN analyses. Finally a Redundant analysis (RDA) was done revealing similar environmental factors responsible for the spider species distribution, as a good separation of the different forest types as well as the separation of the microhabitat groupings from the TWINSPAN. Overall the study revealed that the spider communities differed between the forest types as well as between the microhabitat structures and thus species distribution changed within a forest stand on a fine spatial scale. It was documented that the structure of managed forests affects the composition of spider assemblages compared to natural forests significantly and even small scale-heterogeneity seems to influence the spider species composition.
In current practice, business processes modeling is done by trained method experts. Domain experts are interviewed to elicit their process information but not involved in modeling. We created a haptic toolkit for process modeling that can be used in process elicitation sessions with domain experts. We hypothesize that this leads to more effective process elicitation. This paper brakes down "effective elicitation" to 14 operationalized hypotheses. They are assessed in a controlled experiment using questionnaires, process model feedback tests and video analysis. The experiment compares our approach to structured interviews in a repeated measurement design. We executed the experiment with 17 student clerks from a trade school. They represent potential users of the tool. Six out of fourteen hypotheses showed significant difference due to the method applied. Subjects reported more fun and more insights into process modeling with tangible media. Video analysis showed significantly more reviews and corrections applied during process elicitation. Moreover, people take more time to talk and think about their processes. We conclude that tangible media creates a different working mode for people in process elicitation with fun, new insights and instant feedback on preliminary results.
The effect of tannins on mediterranean ruminant ingestive behavior the role of the oral cavity
(2011)
Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion according to animal physiological limits of tolerance for plant secondary metabolites. This review will detail the effects of dietary tannins on feeding behavior, and the role of the oral cavity in this process, with focus on such ruminant species. The role of salivary protein profile in tannin perception in the oral cavity, and as a defense mechanism, will be discussed.
In this work, we present theoretical simulations of laser-driven vibrational control of NO adsorbed on a gold surface. Our goal is to tailor laser pulses to selectively excite specific modes and vibrational eigenstates, as well as to favor photodesorption of the adsorbed molecule. To this end, various control schemes and algorithms are applied. For adsorbates at metallic surfaces, the creation of electron hole pairs in the substrate is known to play a dominant role in the transfer of energy from the system to the surroundings. These nonadiabatic couplings are included perturbatively in our reduced density matrix simulations using a generalization of the state-resolved position-dependent anharmonic rate model we recently introduced. An extension of the reduced density matrix is also proposed to provide a sound model for photodesorption in dissipative systems.