Genghis Khan (Gek) as a putative effector for Drosophila Cdc42 and regulator of actin polymerization

The small GTPases Cdc42 and Rac regulate a variety of biological processes, including actin polymerization, cell proliferation, and JNK/mitogen-activated protein kinase activation, conceivably via distinct effectors. Whereas the effector for mitogen-activated protein kinase activation appears to be p65PAK, the identity of effector(s) for actin polymerization remains unclear. We have found a putative effector for Drosophila Cdc42, Genghis Khan (Gek), which binds to Dcdc42 in a GTP-dependent and effector domain-dependent manner. Gek contains a predicted serine/threonine kinase catalytic domain that is 63% identical to human myotonic dystrophy protein kinase and has protein kinase activities. It also possesses a large coiled-coil domain, a putative phorbol ester binding domain, a pleckstrin homology domain, and a Cdc42 binding consensus sequence that is required for its binding to Dcdc42. To study the in vivo function of gek, we generated mutations in the Drosophila gek locus. Egg chambers homozygous for gek mutations exhibit abnormal accumulation of F-actin and are defective in producing fertilized eggs. These phenotypes can be rescued by a wild-type gek transgene. Our results suggest that this multidomain protein kinase is an effector for the regulation of actin polymerization by Cdc42.     

Irreführende Leitbilder Zum Mythos der Individualisierung durch pharmakogenetische Behandlungskonzepte. Eine kritische Anmerkung

Zusammenfassung Die prospektive Analyse der ethischen Implikationen medizinisch-technischer Innovationen läuft immer auch Gefahr, sich in den Wunschbildern von Marketingexperten zu verfangen. Vor diesem Hintergrund könnte es durchaus nützlich sein, die Erkenntnisse der Wissenschafts- und Technikforschung zur Genese und Entwicklung neuer Techniken auszuschöpfen. Dies erscheint gerade auch für die ins Phantastische weisende Zukunft der Individualisierung medikamentöser Therapie, wie man ihr häufig in der Beschreibung pharmakogenetischer Behandlungskonzepte begegnet, angebracht. Techniken, die sich noch im Entwicklungsstadium befinden und deren breite Anwendung noch einige Jahre auf sich warten lassen wird, sollten sehr sorgfältig auf ihren Realitätsgehalt und das zu erwartende Leistungspotenzial hin analysiert werden. Dazu gehört v. a. auch eine kritische Auseinandersetzung mit den Leitbildern, Visionen und Nutzenversprechen, mit denen technische Innovationen oft sehr absichtsvoll ausgestattet werden. Wird dabei die Distanz zur Rhetorik der Protagonisten der neuen Techniken nicht gewahrt, gerät die ethische Reflexion unvermittelt in die Rolle, profane Marketingstrategien wortgewandt und ideenreich zu veredeln.     

Beyond imprisonment of meaning: Technology facilitating redefining

Defining is a natural and necessary response to an ambiguous world, but causes fixation of categories and perspectives. On the basis of two earlier studies of project groups, we came to argue that redefining, and hence constructing various ways in which one perceives and understands something, enables groups to overcome imprisonment in meaning, establishing continuous development and flexibility. In this article, we first build a rationale for facilitating a process of redefining, to be taken into account when designing technology. Departing from this rationale, we discuss features of groupware technology that permit change by being flexible, and evoke redefining by engaging the user more actively. In so doing, we argue to think along new lines in the design of communication and collaboration technology. This paper proposes a specific perspective on technology, facilitating groups to engage in a productive, creative fashion of exploiting meaning potential.     

Chemical composition of new copper alloys for machining and its effect on their susceptibility to corrosion cracking

Zinc‐containing copper alloys, the so‐called α + β brasses, are commonly used in contact with potable water. These materials are alloyed with lead to improve machinability. In wrought special brass alloys, reducing the content of this alloying element or replacing it with alternative alloying additions may give rise to a new type of machinable copper alloys which differ from the original alloys by their contents of other modifier elements such as Si (or possibly, Mg, Bi, and P). These alloys have a very low content of lead required for the break‐up of chips during machining. Even though these types of brass exhibit a very good machinability, the effects of their chemical composition on the resistance of the alloy to corrosion cracking have not yet been given sufficient attention. This paper aims to present an assessment of three new types of machinable copper alloys regarding their susceptibility to stress corrosion cracking, in comparison to that of the lead‐alloyed variety, in 0.05 M NaCl, NaNO₂, and Na₂SO₄ solutions. The slow strain rate test has been used for this purpose, and its results were correlated with metallographic evaluation of the number and depth of the cracks observed on the test specimen surfaces on completion of the test.     

The combustion products of polymeric materials. III: GC–MS Analysis of the combustion products of polyethylene,polypropylene, polystyrene and polyamide

A series of gas chromatographic–mass spectrometric analyses was carried out on polyethylene, polypropylene, polystyrene and polyamide in CAB 4.5 and CAB 650 chambers in the flaming and non-flaming combustion mode. The combustion products formed were identified and used to characterize the combustion process in both chambers; procedures were selected for testing polymeric materials for the dangerous effects of their combustion products.     

Does disclosure of emotions facilitate recovery from bereavement? Evidence from two prospective studies.

Two longitudinal studies assessed whether disclosure of emotions facilitates recovery from bereavement. Study 1 tested prospectively over a 2-year period whether the extent to which bereaved persons talked about their loss to others and disclosed their emotions was associated with better adjustment to the loss of a marital partner. There was no evidence that disclosure facilitated adjustment. Study 2 randomly assigned recently bereaved individuals either to the Pennebaker writing task (J. W. Pennebaker & S. K. Beall, 1986) or to no-essay control conditions. The writing task did not result in a reduction of distress or of doctors visits either immediately after the bereavement or at a 6-month follow-up. Beneficial effects were not demonstrated for bereaved persons who had suffered an unexpected loss or who at the time of the study still expressed a high need for emotional disclosure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prospective/intentional and incidental everyday memory: Effects of age and passage of time.

Investigated the effects of age and passage of time on incidental and prospective/intentional everyday memory. 79 23–93 yr old volunteers were tested twice, and 33 of the Ss were tested 3 times over an 18-mo period. They were asked to recognize or recall, either in writing or orally, experiences from a 3-day period in which they served as research Ss. Results demonstrate that incidental, but not prospective/intentional, memory appeared to be influenced by age and passage of time. Results imply that salience and context are important factors in aging memory performance and that certain types of everyday retrospective reports may be reliable. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

OLED科技的未来最大功率效益的重要性

虽然最近几年有机发光二极管(Organic LjghtEmission Diode,OLED)显示器已经商品化,不过OLED显示器不论是发光效率、使用寿命,或是改用无晶硅基大型面板等问题仍有待改善.