Probing conserved amino acids in phospholipase D (Brassica oleracea var. capitata) for their importance in hydrolysis and transphosphatidylation activity

In addition to hydrolysis of glycerophospholipids, phospholipases D (PLDs) catalyze the head group exchange. The molecular basis of this transphosphatidylation potential, which strongly varies for PLDs from different sources, is unknown hitherto. Recently, the genes of two PLD isoenzymes from white cabbage have been sequenced and expressed in Escherchia coli, yielding the basis for mutational studies. In the present paper, three sequence characteristics of the isoenzyme (PLD2) that corresponds to the often used enzyme isolated from cabbage leaves have been probed for their importance in hydrolysis as well as transphosphatidylation activities: (i) the two HKD motifs, (ii) the C terminus and (iii) the eight cysteine residues. All these regions or amino acids are highly conserved in alpha-type plant PLDs. Based on multiple alignments, predictions of secondary structure and comparisons of hydrophobicity profiles, 35 enzyme variants were created and assayed. All positions tested proved to be very sensitive towards amino acid exchanges with respect to hydrolytic activity in the absence of glycerol as well as to the ratio of hydrolytic and transphosphatidylation activities in the presence of glycerol. A significant increase of total activity and transphosphatidylation activity could be obtained by the substitutions C310S and C625S.     

Highly active screen-printed IrTi4O7 anodes for proton exchange membrane electrolyzers

Electroceramic support materials can help reducing the noble-metal loading of iridium in the membrane electrodes assembly (MEA) of proton exchange membrane (PEM) electrolyzers. Highly active anodes containing Ir-black catalyst and submicronic Ti₄O₇ are manufactured through screen printing technique. Several vehicle solvents, including ethane-1,2-diol; propane-1,2-diol and cyclohexanol are investigated. Suitable functional anodic layer with iridium loading as low as 0.4 mg cm^?2 is obtained. Surface properties of the deposited layers are investigated by atomic force microscopy (AFM). The most homogeneous coating with the highest electronic conductivity is obtained using cyclohexanol. Tests in PEM electrolyzer operating at 1.7 V and 40 °C demonstrate that the CCM with anode coated with cyclohexanol presents a 1.5-fold higher Ir-mass activity than that of the commercial CCM.     

Bioaccumulation of cyanuric acid in edible tissues of shrimp following experimental feeding

Due to concerns that cyanuric acid (CYA)-contaminated feed had been used in aquaculture and could enter the human food chain, a method to quantify CYA residues in the edible tissues of fish and shrimp was previously developed and validated. This paper provides further data on the deliberate feeding of CYA to shrimp to determine the extent of residue accumulation in edible tissue. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for the analysis of CYA in shrimp tissue. Edible tissue of shrimp fed 1666 or 3333 mg kg?1 CYA in their diet (approximately 55 and 124 mg kg?1 body weight) contained 0.767 and 0.406 mg kg?1 CYA, respectively. The residue levels are below the World Health Organization (WHO) tolerable daily intake level for CYA and are generally considered unlikely to pose a human health risk.     

Stability of Older Adults' Preferences for Life-Sustaining Medical Treatment.

The use of instructional advance directives assumes that preferences for life-sustaining medical treatment remain stable over time and across changes in life condition. A sample of 332 older adults recorded their preferences for 4 life-sustaining treatments in 9 illness scenarios. These preferences were elicited again 1 and 2 years after the original interview. Overall, preferences for life-sustaining treatment were moderately stable over time, but stability varied significantly across judgments. Preferences were most stable for illness scenarios that were most and least serious and for decisions to refuse treatment. Age, gender, education, and prior completion of an advance directive were all related to preference stability, and evidence indicated that declines in physical or psychological functioning resulted in decreased interest in life-sustaining treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A∕E∕C Teamwork: A Collaborative Design and Learning Space

This paper describes an ongoing effort focused on combined research and curriculum development for multidisciplinary, geographically distributed architecture∕engineering∕construction (A∕E∕C) teamwork. It presents a model for a distributed A∕E∕C learning environment and an Internet-based Web-mediated collaboration tool kit. The distributed learning environment includes six universities from Europe, Japan, and the United States. The tool kit is aimed to assist team members and owners (1) capture and share knowledge and information related to a specific project; (2) navigate through the archived knowledge and information; and (3) evaluate and explain the product's performance. The A∕E∕C course offered at Stanford University acts as a testbed for cutting-edge information technologies and a forum to teach new generations of professionals how to team up with practitioners from other disciplines and take advantage of information technology to produce a better, faster, more economical product. The paper presents new assessment metrics to monitor students' cross-disciplinary learning experience and track programmatic changes. The paper concludes with challenges and quandaries regarding the impact of information technologies on team performance and behavior.     

Coping with identity threat: The role of religious orientation and implications for emotions and action intentions.

Religiosity is typically related to positive outcomes following distress, yet it remains unclear how religiosity may alter responses when one's religious identity itself is challenged. The present investigation examined the role of appraisal-coping processes in the relations between religious orientations, emotions, and action intentions following identity threat. Study 1 (N = 63) assessed associations with religious orientations (intrinsic and extrinsic) following a threat targeting one's religion. Although both orientations evoked a broad array of responses, those related to an intrinsic orientation were stronger and included more negative reactions (e.g., sadness, confrontation). Study 2 (N = 59) evaluated the impact of a nonreligious identity threat, which elicited only adaptive responses (i.e., problem-focused coping, support seeking) that were associated with an intrinsic orientation. Appraisal-coping processes mediated relations between religiosity and responses to an identity threat in both studies but were most evident following religious threat. Taken together, these findings suggest that whereas an extrinsic religious orientation may function as a social identity in response to religious threats, the positive effects of an intrinsic religious orientation appear to be undermined by threats targeting the social group and belief system therein. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Hand supports to assist toilet use among the elderly

Improving the toilet environment holds promises for increasing the quality of life for elderly and disabled persons. This is one of the goals of the Friendly Rest Room (FRR) project. The study described in this article explored the preference and use of supports in the toilet environment during the entire toilet ritual. An adjustable test frame was built with a toilet and three types of supports. Fourteen subjects were asked which positions they favoured for each support. After using all three supports, they were asked which support they found most comfortable. In general, the preferred positions depended on personal preferences more than on dimensions of the body. It was concluded that there is a preference for vertical supports for sitting down and standing up. During toilet use the side supports were equally appreciated.     

Person-centered technology enhanced learning: Dimensions of added value

Extensive research has shown that person-centered learning aiming at students’ development on the levels of intellect, skills, and attitudes is effective in face-to-face education. More recently, advances in web-technology let us ask: Is humanistic, person-centered learning also effective along the application of modern technology? In this contribution we reflect 10 years of research at the University of Vienna, Austria. Essentially, we found that, given learners perceive the teacher’s or facilitator’s person-centered attitudes and courses employ a thoughtful blend of face-to-face and online elements, courses tend to be perceived by students as carrying value far beyond just cognitive gains: for example, students indicate that – more than with traditional instruction – they are motivated to engage in active, self-initiated learning. In particular, they improve their team skills, interpersonal relationships, and become better listeners. They learn significantly from the multiple perspectives they perceive.     

NTM gedenkt—Dirk Jan Struik 30. September 1894–21. Oktober 2000

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