The beta subunit of the signal recognition particle receptor is a transmembrane GTPase that anchors the alpha subunit, a peripheral membrane GTPase, to the endoplasmic reticulum membrane.

The signal recognition particle receptor (SR) is required for the cotranslational targeting of both secretory and membrane proteins to the endoplasmic reticulum (ER) membrane. During targeting, the SR interacts with the signal recognition particle (SRP) which is bound to the signal sequence of the nascent protein chain. This interaction catalyzes the GTP-dependent transfer of the nascent chain from SRP to the protein translocation apparatus in the ER membrane. The SR is a heterodimeric protein comprised of a 69-kD subunit (SR alpha) and a 30-kD subunit (SR beta) which are associated with the ER membrane in an unknown manner. SR alpha and the 54-kD subunits of SRP (SRP54) each contain related GTPase domains which are required for SR and SRP function. Molecular cloning and sequencing of a cDNA encoding SR beta revealed that SR beta is a transmembrane protein and, like SR alpha and SRP54, is a member of the GTPase superfamily. Although SR beta defines its own GTPase subfamily, it is distantly related to ARF and Sar1. Using UV cross-linking, we confirm that SR beta binds GTP specifically. Proteolytic digestion experiments show that SR alpha is required for the interaction of SRP with SR. SR alpha appears to be peripherally associated with the ER membrane, and we suggest that SR beta, as an integral membrane protein, mediates the membrane association of SR alpha. The discovery of its guanine nucleotide-binding domain, however, makes it likely that its role is more complex than that of a passive anchor for SR alpha. These findings suggest that a cascade of three directly interacting GTPases functions during protein targeting to the ER membrane

Ermittlung der Griffikeit von Verkehrsflächen mittels KFZ-Datenspeicherung

Das Forschungsprojekt betrifft ein Verfahren und eine Vorrichtung zur Ermittlung der Griffigkeit von Verkehrsoberflächen mittels Daten, die von einem Satelliten-Navigations-System in Verbindung mit Kfz-typischen Daten während eines Bremsvorganges erhalten werden. Die Bewegungsdaten des Fahrzeuges werden aus relativ genauen Navigationsinformationen in sehr kurzen Zeitintervallen per Funkübertragung oder direkt im Fahrzeug auf einem Datenträger abgelegt. Hieraus werden die ortsbezogenen Bremsverzögerungen ermittelt und ggf. mit denjenigen eines mitgeführten Beschleunigungsmeßgerätes verglichen. Aus den Bremsverzögerungen werden in Verbindung mit den Kfz-Kennwerten und der Straßengeometrie die jeweils ausnutzbaren Kraftschlussbeiwerte (sog. Reibwertmaxima) bzw. die örtliche Griffigkeit der Verkehrsoberfläche ermittelt

North Carolina Organic Vegetable Production Cost Study

Crop Production/Industries,

Book Review Department : SOCIAL REALITIES AND THE SOCIAL WORK RESPONSE: THE ROLE OF SCHOOLS OF SOCIAL WORK, Proceedings of the XVIIIth International Congress of Schools of Social Work. New York : Inter national Association of Schools of Social Work, 1977

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67864/2/10.1177_002087287802100109.pd

Education for Sustainability: The Effectiveness of a Place Based Environmental Education Unit in Food Waste Reduction on the Environmental Awareness of Fourth Grade Students

Implementation of a place-based composting unit for food reduction in the Spring of 2019 with 10 fourth-grade students utilized qualitative methodologies in order to measure its effects on environmental awareness in the individuals. Guided by Capra’s (1997) notion of sustainability in an ecoliterate society and Sobel’s (2008) place-based pedagogy, the curriculum and instructional decisions during the construction of the unit utilized read alouds and outdoor activities that aimed to increase the students’ connectedness to their local setting in order to motivate students for engagement in ecoliterate behaviors. Pre- and post-intervention surveys, artifacts and exit slips in student nature journals, teacher-researcher field notes, and formal interviews each developed rich data which were first examined individually. From these independent data analyses, three themes then emerged that holistically captured the overall findings of the study; (a) students developed a heightened level of connectedness to nature, (b) an increase in sense of empowerment, and (c) expressed an overall value of ecoliteracy in school settings. Results from this action research suggests a place based environmental education approach has a positive effect in fostering environmental awareness of fourth grade students. The results of the study also suggest that ecoliteracy, as both a framework for sustainable practices and character development, should further be explored because of its effects on empowering students for positive change and actively engaging students in class activities