22 research outputs found
Scalable Generation of Synthetic GPS Traces with Real-life Data Characteristics
Database benchmarking is most valuable if real-life data and workloads are
available. However, real-life data (and workloads) are often not publicly
available due to IPR constraints or privacy concerns. And even if
available, they are often limited regarding scalability and variability of
data characteristics. On the oth
Chromatin Immunoprecipitation to Analyze DNA Binding Sites of HMGA2
BACKGROUND: HMGA2 is an architectonic transcription factor abundantly expressed during embryonic and fetal development and it is associated with the progression of malignant tumors. The protein harbours three basically charged DNA binding domains and an acidic protein binding C-terminal domain. DNA binding induces changes of DNA conformation and hence results in global overall change of gene expression patterns. Recently, using a PCR-based SELEX (Systematic Evolution of Ligands by Exponential Enrichment) procedure two consensus sequences for HMGA2 binding have been identified. METHODOLOGY/PRINCIPAL FINDINGS: In this investigation chromatin immunoprecipitation (ChIP) experiments and bioinformatic methods were used to analyze if these binding sequences can be verified on chromatin of living cells as well. CONCLUSION: After quantification of HMGA2 protein in different cell lines the colon cancer derived cell line HCT116 was chosen for further ChIP experiments because of its 3.4-fold higher HMGA2 protein level. 49 DNA fragments were obtained by ChIP. These fragments containing HMGA2 binding sites have been analyzed for their AT-content, location in the human genome and similarities to sequences generated by a SELEX study. The sequences show a significantly higher AT-content than the average of the human genome. The artificially generated SELEX sequences and short BLAST alignments (11 and 12 bp) of the ChIP fragments from living cells show similarities in their organization. The flanking regions are AT-rich, whereas a lower conservation is present in the center of the sequences
An epitaph to Section 28? Telling tales out of school about changes and challenges to discourses of sexuality
This is a postprint of an article whose final and definitive form has been published in the International Journal of Qualitative Studies in Education,© 2007 Copyright Taylor & Francis; International Journal of Qualitative Studies in Education, is available online at http://www.informaworld.comThis article seeks to develop an understanding of the professional and personal lives of LGBT teachers in relation to the discriminatory statute Section 28, which prohibited 'promotion' of 'the acceptability of homosexuality as a pretended family relationship' by local education authorities in the UK (except Northern Ireland). Interviews with a small sample of serving teachers are analysed using a feminist poststructuralist methodology to discover whether the removal of this legislation marks a shift in theorization, policy or practice. Findings are arranged to focus on the workings of official policy, on informal or unofficial classroom and staffroom practices, and on relations with a local community. Analysis and discussion reveal a complex matrix of constituents (space, relationships and other variables) only some of which respond to the (perhaps) superficial stimulus of legislative change. Such change goes only a small way to challenge a deeply embedded discourse of inequality, which may respond only to a more profound epistemological transformation
Effect of seasonal large amplitude internal waves (LAIW) on annual coral growth and skeletal density of the coral Purites lutea.
In-Situ Activity of the Heterotrophic Microbial Community in Seep Sediments from the Santa Monica Basin
The role of microbes in marine sediments is of great importance for the understanding of processes and elemental cycles in the ocean. However, many microbes inhabiting the seafloor remain unculturable because the in-situ conditions are difficult to mimic in a laboratory setting. Incubations of sediment slurries are likewise limited as the retrieval of sample material from the seafloor is associated with depressurization and disruption of the sedimentary matrix, with still unknown effects on the microbial community and its activity.
To overcome some limitations of in vitro studies, we used an in-situ injector coring system deployed in the deep sea by a remotely operated vehicle. Specially designed push cores enable the injection of different substrates, including stable isotope labeled compounds, into the sediment, allowing an incubation directly in the deep-sea environment with minimal disturbance of the microbial community. For this study, an injector core and a reference neighboring push core without injected fluid were inserted in the center of an orange-colored sulfur-oxidizing microbial mat at an active methane seep in the Santa Monica Basin at 800 m water depth (Fig. 1a, b). 13C-labeled glucose, deuterated water and homopropargylglycine (HPG), an alkyne modified methionine analog, were injected through multiple needles aligned along the vertical core axis into the sediment. The core was incubated directly at the seafloor with the goal of better understanding the activity and diversity of heterotrophic microorganisms within this seep setting under in situ conditions. A similar injector core approach with 13C-labeled glucose (Takano et al., 2010) demonstrated archaeal activity after 9 days through the labeling of the glycerol backbone of archaeal membrane lipids. Here, we expand the scope of injected stable isotope labels and combine them with single cell resolved biorthogonal non-canonical amino acid tagging (BONCAT; Hatzenpichler et al., 2016) and fluorescence in situ hybridization microscopy (FISH) over a relatively short incubation period
Scalable Generation of Synthetic GPS Traces with Real-life Data Characteristics
Database benchmarking is most valuable if real-life data and workloads are
available. However, real-life data (and workloads) are often not publicly
available due to IPR constraints or privacy concerns. And even if
available, they are often limited regarding scalability and variability of
data characteristics. On the oth
G Protein-Independent Inhibition of GIRK Current by Adenosine in Rat Atrial Myocytes Overexpressing A1 Receptors after Adenovirus-Mediated Gene Transfer
G protein-activated inwardly rectifying K+ (GIRK) channels, important regulators of membrane excitability in the heart and central nervous system, are activated by interaction with ÎČÎł subunits from heterotrimeric G proteins upon receptor stimulation. In atrial myocytes various endogenous receptors couple to GIRK channels, including the canonical muscarinic M2 receptor (M2AChR) and the A1 adenosine receptor (A1AdoR). Saturating stimulation of A1AdoR in atrial myocytes activates only a fraction of the GIRK current that is activated via M2AChR, which reflects a lower density of A1AdoR. In the present study A1AdoR were overexpressed by means of adenovirus-mediated gene transfer using green fluorescent protein (GFP) as the reporter. Confirmatory to a previous study, this resulted in an increased sensitivity of macroscopic GIRK current (ACh-activated K+ current (IK(ACh))) to stimulation by Ado. However, in the majority of GFP-positive myocytes, exposure to Ado at concentrations â„ 1 ÎŒm resulted in activation of IK(ACh) followed by a rapid inhibition. In those cells a rebound activation of current was recorded upon washout of Ado. The inhibitory component could be recorded in isolation when IK(ACh) was activated by M2AChR-stimulation and brief pulses of Ado were superimposed. In myocytes loaded with GTP-Îł-S, IK(ACh), irreversibly activated by brief exposure to agonist, was still reversibly inhibited by Ado, suggesting that inhibition is independent of G protein cycling. In myocytes co-transfected with adenoviral vectors encoding A1AdoR and GIRK4 subunit, no inhibition of GIRK current by Ado was observed. As acute desensitization of atrial GIRK current, which is reminiscent of the inhibition described here, has been shown to be absent in myocytes overexpressing GIRK4, this suggests that acute desensitization and the novel inhibition might share a common pathway whose target is the GIRK channel complex or its GIRK1 subunit