The murmur of old broken heartstrings

Although it has long been hypothesized that gene expression might become more variable or noisy during aging, direct evidence has been scarce so far. A new study reports detection, by PCR analysis of individual cells, of increased cell-to-cell variability in gene expression in aging mouse heart; moreover, a similar variability can be generated in cultured cells using oxidative stress (Bahar et al., 2006)

Charge-coupled-device parallel-to-serial converter

A CCD parallel-to-serial converter comprising two successions of charge transfer stages, recurrently side-loaded with respective ones of parallelly supplied charge packets, then serially unloaded by time-interleaved respective shift register operations. The charge packets converted to time-division-multiplexed serial form are supplied to a shared electrometer, and the electrometer response is de-multiplexed. Preferably, shift register operations are carried forward concurrently at the same rate, but with the final charge transfer stages clocked in phases staggered in time

The genetics of gender and life span

Several possible and potentially overlapping genetic mechanisms have been suggested to explain differences in life span between males and females. Two recent papers in BMC Evolutionary Biology on the effects of inbreeding provide additional insight into the genetic architecture underlying life span differences between genders in two different insects

The JPL telerobot operator control station. Part 1: Hardware

The Operator Control Station of the Jet Propulsion Laboratory (JPL)/NASA Telerobot Demonstrator System provides the man-machine interface between the operator and the system. It provides all the hardware and software for accepting human input for the direct and indirect (supervised) manipulation of the robot arms and tools for task execution. Hardware and software are also provided for the display and feedback of information and control data for the operator's consumption and interaction with the task being executed. The hardware design, system architecture, and its integration and interface with the rest of the Telerobot Demonstrator System are discussed

A search for doxycycline-dependent mutations that increase Drosophila melanogaster life span identifies the VhaSFD, Sugar baby, filamin, fwd and Cctl genes

BACKGROUND: A P-type transposable element called PdL has been engineered with a doxycycline-inducible promoter directed out through the 3' end of the element. Insertion of PdL near the 5' end of a gene often yields doxycycline-dependent overexpression of that gene and a mutant phenotype. This functional genomics strategy allows for efficient screening of large numbers of genes for overexpression phenotypes. RESULTS: PdL was mobilized to around 10,000 new locations in the Drosophila melanogaster genome and used to search for genes that would extend life span when overexpressed. Six lines were identified in which there was a 5-17% increase in life span in the presence of doxyxcycline. The mutations were molecularly characterized and in each case a gene was found to be overexpressed using northern blots. Two genes did not have previously known phenotypes and are implicated in membrane transport: VhaSFD encodes a regulatory subunit of the vacuolar ATPase proton pump (H(+)-ATPase), whereas Sugar baby (Sug) is related to a maltose permease from Bacillus. Three PdL mutations identified previously characterized genes: filamin encodes the homolog of an actin-polymerizing protein that interacts with presenilins. four wheel drive (fwd) encodes a phosphatidylinositol-4-kinase (PI 4-kinase) and CTP:phosphocholine cytidylyltransferase-l (Cctl) encodes the rate-limiting enzyme in phosphatidylcholine synthesis. Finally, an apparently novel gene (Red herring, Rdh) was found in the first intron of the encore gene. CONCLUSIONS: Screening for conditional mutations that increase Drosophila life span has identified genes implicated in membrane transport, phospholipid metabolism and signaling, and actin cytoskeleton organization

Understanding Lifeguard Recruitment and Selection Practices in Victorian Aquatic and Recreation Centers (ARCs)

Extensive research has focused on human resource management (HRM) and recruitment and selection practices across different settings. However, there is a gap in the scholarly literature in ARC settings, including lifeguards. Additionally, the aquatics industry is experiencing unprecedented levels of lifeguard turnover within aquatic facilities. The recruitment and selection process can impact employee turnover. Therefore, an important first step to address lifeguard turnover is to better understand the current recruitment and selection practices of lifeguards. This study focuses on the recruitment and selection practices of ARC management to better understand the recruitment and selection of lifeguards. The analysis is based on 16 semi-structured interviews with ARC managers involved in lifeguard recruitment and selection. Participants included center managers, assistant center managers, and operations managers/coordinators. A deductive analysis was able to effectively explain the current recruitment and selection practices for recruiting lifeguards in Victorian ARCs

Simultaneous tracking of fly movement and gene expression using GFP

<p>Abstract</p> <p>Background</p> <p>Green Fluorescent Protein (GFP) is used extensively as a reporter for transgene expression in Drosophila and other organisms. However, GFP has not generally been used as a reporter for circadian patterns of gene expression, and it has not previously been possible to correlate patterns of reporter expression with 3D movement and behavior of transgenic animals.</p> <p>Results</p> <p>We present a video tracking system that allows tissue-specific GFP expression to be quantified and correlated with 3D animal movement in real time. <it>eyeless/Pax6 </it>reporter expression had a 12 hr period that correlated with fly activity levels.</p> <p><it>hsp70 </it>and <it>hsp22 </it>gene reporters were induced during fly aging in circadian patterns (24 hr and 18 hr periods, respectively), and spiked in the hours preceding and overlapping the death of the animal. The phase of <it>hsp </it>gene reporter expression relative to fly activity levels was different for each fly, and remained the same throughout the life span.</p> <p>Conclusion</p> <p>These experiments demonstrate that GFP can readily be used to assay longitudinally fly movement and tissue-specific patterns of gene expression. The <it>hsp22</it>-GFP and <it>hsp70</it>-GFP expression patterns were found to reflect accurately the endogenous gene expression patterns, including induction during aging and circadian periodicity. The combination of these new tracking methods with the <it>hsp</it>-GFP reporters revealed additional information, including a spike in <it>hsp22 </it>and <it>hsp70 </it>reporter expression preceding death, and an intriguing fly-to-fly variability in the phase of <it>hsp70 </it>and <it>hsp22 </it>reporter expression patterns. These methods allow specific temporal patterns of gene expression to be correlated with temporal patterns of animal activity, behavior and mortality.</p