Regulating self-organized collaborative learning: the importance of homogeneous problem perception,immediacy and intensity of strategy use

Very often, university students deliberately form self-organized study groups, e.g. to study collaboratively for an upcoming exam. Yet, very little is known about what regulation problems such self-organized study groups encounter during their learning process and how they try to cope with these problems. Therefore, this study investigates how completely self-organized groups (i.e., non-guided groups outside the classroom that form without external impulse) regulate their collaborative learning process when faced with different kinds of regulation problems. More specifically, we tested the hypotheses that members of self-organized study groups are more satisfied with their group learning experience (a) the more homogeneous their problem perceptions are within their group, (b) the more they apply immediate (rather than non-immediate) strategies to remedy their regulation problems, and (c) the more frequently they apply regulation strategies. In a longitudinal study, N?=?122 students, voluntarily studying for their exams in N?=?52 groups, were asked to indicate the types of problems they experienced, the types of strategies they used to tackle those problems, and their satisfaction with their group learning experience after each of their self-organized study meetings. Hierarchical linear modeling confirmed all hypotheses. Qualitative analysis of two selected groups’ self-reported situational data provided additional insights about the mechanisms that may have contributed to the results. Our study provides important directions for future research, including the recommendation to identify the processes by which groups (a) can reach homogeneity of problem perceptions and (b) coordinate the choice of appropriate strategies within the group.

     

Erschließung eines Marmorkarstvorkommens als mitteltiefer Erdwärmesondenspeicher im Tuxertal,Tirol

Borehole heat exchangers can be economically beneficial for meeting heating and cooling demands of houses or buildings. In karst aquifers development of thermal storage and exchange systems may be problematic in terms of groundwater protection and storage design, due to possibly high groundwater velocities. The new development of the Hochstegen marble unit in the Tux Valley (Zillertal, Austria) was designed in two stages for the requested cooling and heating demands. An enhanced geothermal response test was completed using optical frequency domain reflectometry in an exploration drillhole. Additional studies focussing on local geology and hydrology were also conducted. Geothermal parameters obtained at precise depths allowed differentiating between conductive and convective heat flow and were correlated with the lithostratigraphically-conditioned karst characteristics. The borehole heat exchanger field was developed with nine 400 m deep dual U?shaped tube probes in 2013 for 1 GWh/a extraction and 400 MWh/a induction. Along with borehole geophysics and geothermal response tests, the study has provided relevant geothermal data for improving storage design and exploration.     

Ausbreitung und Vermischung geogener,kohlendioxidführender Thermalsole in oberflächennahem Grundwasser,Bad Nauheim

Anomalous high temperatures, salt contents and carbon dioxide concentrations were detected in shallow groundwater in the famous Art Deco ensemble, Sprudelhof. A carbon dioxide lifted thermal brine is discharged by ancient wells down to 180 m deep. Since 1856, the well installation had been operated without any changes and a low level of maintenance. During the last centuries, however, numerous anthropogenic interventions in the Sprudelhof’s underground led to changes of the natural brine system, as well as mixing, dilution and expansion processes in the near-surface aquifers. Recently, the thermal brine has been escaping from the well bore by uncontrolled means, contaminating the shallow underground. Corrosion of the casings has allowed the natural mixing system to reactivate. A groundwater monitoring network containing Duo-wells, allows independent samplings of the liquid and gaseous phases. Coinciding brine-groundwater mixing ratios were calculated for the two uppermost aquifers, as well as a gradient for increasing electric conductivities with depth.     

Osteopromotion with a plasmatransglutaminase on a β-TCP ceramic

We investigated the osteopromotive properties of plasmatransglutaminase (F XIII), bone marrow and venous blood on a resorbable β-tricalcium phosphate (β-TCP) scaffold. A baseline binding and release study of F XIII from the scaffold showed a continuous release of 18% of the total dose after 48 h. The main study consisted of 18 adult sheep with cylindrical defects in both tibiae. The defects were filled with a β-TCP cylinder impregnated either with bone marrow, venous blood, F XIII or sheep were treated with 1250 IU F XIII intravenously over 14 days (n = 4 in each group). The defects were left open in two sheep. QCT and histology was performed after 6 and 12 weeks. The best bone ingrowth was seen after 6 weeks in the bone marrow group and after 12 weeks in the local F XIII group. The highest ingrowth on the inside of the cylinder proving the osteopromoting potential of F XIII was found in the local F XIII group. In our opinion F XIII is a good and readily available osteopromoting agent which can be used with β-TCP in cases of bone deficit to promote bone regeneration.     

Whole model empirical validation on a full-scale building

This paper describes an empirical validation study undertaken on two identical full-size buildings within the scope of the IEA ECB Annex 58 project. Details of the experimental configuration and monitoring are included, together with results from measurements and from predictions made by 21 modelling teams using commercial and research simulation programmes. The two-month, side-by-side experiment was undertaken on buildings with high levels of thermal mass and in a period with high solar gains. The detailed specification and associated measurement data provide a useful empirical validation dataset for programme testing. Results from the modelling demonstrate good agreement between measured data and predictions for a number of programmes, in both absolute predictions of temperatures and heat inputs as well as dynamic response. On the other hand, a significant number of user input errors resulted in poor agreement for other programmes, especially in the blind validation phase of the modelling methodology.     

Exploring fluorescence antibunching in solution to determine the stoichiometry of molecular complexes

Fluorescence antibunching is a well-known technique for determining the number of independent emitters per molecule or molecular complex. It was rarely applied to autofluorescent proteins due to the necessity of collecting large numbers of fluorescence photons from a single molecule, which is usually impossible to achieve with rather photolabile autofluorescent proteins. Here, we measure fluorescence antibunching on molecules in solution, allowing us to accumulate data over a large number of molecules. We use that method for determining an average stoichiometry of molecular complexes. The proposed method is absolute in the sense that it does not need any calibration or referencing. We develop the necessary theoretical background and check the method on pure dye solutions and on molecular complexes with known stoichiometry.     

Stereochemical and steric control of the UDP-glucuronosyltransferase-catalyzed conjugation reaction: a rational approach for the design of inhibitors for the human UGT2B7

A set of 76 derivatives of the epimeric tricyclic sesquiterpenols longifolol and isolongifolol was subjected to inhibition and glucuronidation assays employing the human UDP-glucuronosyltransferase (UGT) 2B7. Detailed structure-activity relationships (SARs) with respect to functionality, stereochemical properties, and steric features were derived. To gain further insight into the SARs of UGT2B7 ligands herein, we have developed a 3D-quantitative structure-activity relationship (3D-QSAR) using Comparative Molecular Similarity Analysis (CoMSIA). The formation of the enzyme-inhibitor complex was predominantly controlled by spatially directed hydrophobic interactions. The glucuronidation rate was significantly influenced by the steric demand of substituents in proximity of the nucleophilic hydroxy group. The glucuronidation of the compounds was prevented by the introduction of bulky substituents such as isopropyl, tert-butyl, and phenyl groups. The epimeric longifolol derivatives of series D were the best inhibitors displaying IC(50) values as low as 4.6 nM. This study shows that high-potency substrates can be turned into potent inhibitors by addressing functional, stereochemical, and steric properties.