633 research outputs found
Octopamine Receptor Gene Expression in Lepidopteran Insects
The invertebrate octopaminergic system affects many diverse processes and represents the counterpart to the vertebrate adrenergic/noradrenergic system with the classes of octopamine receptor (OAR) being homologous to those of vertebrate adrenergic receptors. However, there is still little information on the OARs present in different species, and the levels and distribution of these receptors throughout the body. cDNAs sharing high similarity with known insect OARs were cloned in three lepidopteran species: the cabbage looper, Trichoplusia nr, the true armyworm, Pseudaletia unipuncta; and the cabbage white, Pieris rapae. Seven major larval tissues and one adult tissue were examined in T. ni using quantitative real-time PCR to determine the relative expression levels of receptor transcripts. A subset of these tissues was also examined in P. unipuncta and P. rapae. All receptor transcripts were expressed in the nervous system of all three, however, the distribution of the different receptor types varied between species
Social media, networking, and marketing performance : a study of social enterprises in Hong Kong
Over the past few years, the number of social enterprises has been increasing in Hong Kong. The marketing performance of these social enterprises, however, are found to be problematic. Although some studies have investigated the ways for improving marketing performance of social enterprises through launching various marketing activities, this is surprising that the roles of social media and networking are lacking attention in the literature. In this conceptual paper, we aim at investigating how the implementation of these cost-effective marketing activities, namely (i) social media and (ii) networking, may improve the marketing performance of social enterprises in Hong Kong
VennDiagramWeb: a web application for the generation of highly customizable Venn and Euler diagrams.
BackgroundVisualization of data generated by high-throughput, high-dimensionality experiments is rapidly becoming a rate-limiting step in computational biology. There is an ongoing need to quickly develop high-quality visualizations that can be easily customized or incorporated into automated pipelines. This often requires an interface for manual plot modification, rapid cycles of tweaking visualization parameters, and the generation of graphics code. To facilitate this process for the generation of highly-customizable, high-resolution Venn and Euler diagrams, we introduce VennDiagramWeb: a web application for the widely used VennDiagram R package. VennDiagramWeb is hosted at http://venndiagram.res.oicr.on.ca/ .ResultsVennDiagramWeb allows real-time modification of Venn and Euler diagrams, with parameter setting through a web interface and immediate visualization of results. It allows customization of essentially all aspects of figures, but also supports integration into computational pipelines via download of R code. Users can upload data and download figures in a range of formats, and there is exhaustive support documentation.ConclusionsVennDiagramWeb allows the easy creation of Venn and Euler diagrams for computational biologists, and indeed many other fields. Its ability to support real-time graphics changes that are linked to downloadable code that can be integrated into automated pipelines will greatly facilitate the improved visualization of complex datasets. For application support please contact [email protected]
Principle of Optimal Page Replacement and the LRU Stack Model
Program reference strings generated by the LRU stack model are
considered, and expressions for the expected times to next reference for all pages occupying different LRU stack positions are derived. Using these expressions, necessary and sufficient conditions as well as sufficient conditions on the distance distribution are obtained which guarantee implementation by
the LRU replacement algorithm of the "informal principle of optimality" for
page replacements. The sufficient conditions are found to be the same as those under which the LRU replacement algorithm is shown to be optimal. Relaxed conditions are also obtained for special cases where the number of page frames
is fixed
Post-TTM Rebound Pyrexia after Ischemia-Reperfusion Injury Results in Sterile Inflammation and Apoptosis in Cardiomyocytes
Introduction. Fever is frequently observed after acute ischemic events and is associated with poor outcome and higher mortality.
Targeted temperature management (TTM) is recommended for neuroprotection in comatose cardiac arrest survivors, but
pyrexia after rewarming is proven to be detrimental in clinical trials. However, the cellular mechanisms and kinetics of post-
TTM rebound pyrexia remain to be elucidated. Therefore, we investigated the effects of cooling and post-TTM pyrexia on the
inflammatory response and apoptosis in a cardiomyocyte ischemia-reperfusion (IR) injury model. Methods. HL-1
cardiomyocytes were divided into the following groups to investigate the effect of oxygen-glucose deprivation/reperfusion
(OGD/R), hypothermia (33.5°C), and pyrexia (40°C): normoxia controls maintained at 37°C and warmed to 40°C, OGD/R
groups maintained at 37°C and cooled to 33.5°C for 24 h with rewarming to 37°C, and OGD/R pyrexia groups further warmed
from 37 to 40°C. Caspase-3 and RBM3 were assessed by Western blot and TNF-α, IL-6, IL-1β, SOCS3, iNOS, and RBM3
transcriptions by RT-qPCR. Results. OGD-induced oxidative stress (iNOS) in cardiomyocytes was attenuated post-TTM by
cooling. Cytokine transcriptions were suppressed by OGD, while reperfusion induced significant TNF-α transcription that was
exacerbated by cooling. Significant inductions of TNF-α, IL-6, IL-1β, and SOCS3 were observed in noncooled, but not in cooled
and rewarmed, OGD/R-injured cardiomyocytes. Further warming to pyrexia induced a sterile inflammatory response in
OGD/R-injured groups that was attenuated by previous cooling, but no inflammation was observed in pyrexic normoxia groups.
Moreover, cytoprotective RBM3 expression was induced by cooling but suppressed by pyrexia, correlating with apoptotic
caspase-3 activation. Conclusion. Our findings show that maintaining a period of post-TTM “therapeutic normothermia” is
effective in preventing secondary apoptosis-driven myocardial cell death, thus minimizing the infarct area and further release of
mediators of the innate sterile inflammatory response after acute IR injury
Working-Set-Like Memory Management Algorithms
This paper considers the design and evaluation of memory management
algorithms to be applied to multiprogramming computer systems with virtual
memory. The operation of the Denning working set algorithm is studied and
is recognized to be a replacement process of time indices based on a rule
closely related to the replacement rule of the First-In-First-Out replacement
algorithm. Basing on these analyses, a framework in the time domain is then
proposed. A duality rule capable of transforming a replacement algorithm
in the space domain into a working-set-like algorithm (retention algorithm)
in the time domain is designed. Some properties of these newly-designed
retention algorithms are derived. The performances of some retention
algorithms with respect to their space duals are experimentally studied by
simulation. Results show generally better performance for retention algorithms
than for their space dual replacement algorithms
Two-dimensional projected-momentum covariance mapping for coulomb explosion imaging
We introduce projected-momentum covariance mapping, an extension of recoil-frame covariance mapping for 2D ion imaging studies. By considering the two-dimensional projection of the ion momenta as recorded by the detector, one opens the door to a complex suite of analysis tools adapted from three-dimensional momentum imaging studies. This includes the use of different frames of reference to unravel the dynamics of fragmentation and the application of fragment momentum constraints to isolate specific fragmentation channels. The technique is demonstrated on data from a two-dimensional ion imaging study of the Coulomb explosion of the cis and trans isomers of 1,2-dichloroethene, following strong-field ionization by an intense near-infrared femtosecond laser pulse. Classical simulations are used to guide the interpretation of projected-momentum covariance maps. The results offer a detailed insight into the distinct Coulomb explosion dynamics for this pair of isomers and lay the groundwork for future time-resolved studies of photoisomerization dynamics in this molecular system
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