237 research outputs found
The Effects of Low Dose-Rate Ionizing Radiation on the Shapes of Transients in the LM124 Operational Amplifier
Shapes of single event transients (SETs) in a linear bipolar circuit (LM124) change with exposure to total ionizing dose (TID) radiation. SETs shape changes are a direct consequence of TID-induced degradation of bipolar transistor gain. A reduction in transistor gain causes a reduction in the drive current of the current sources in the circuit, and it is the lower drive current that most affects the shapes of large amplitude SETs
Studies on malarial sporozoites. I. Effect of various environmental conditions
Data are presented on the infectivity of sporozoites of P. gallinaceum under various conditions. Mosquitoes exposed to ether in excess or to temperatures below freezing showed drastic reduction of infectivity. Considerable exposure to tobacco smoke, DDT or pyrethrum, minimal exposure to ether, or chilling at temperatures above freezing were apparently harmless to sporozoites.Saline solutions of 0.21, 0.43 and 0.85% were injurious to sporozoites. In the presence of 4.5% blood 0.85% saline was less deleterious than more or less concentrated saline solutions. Heparinized chick blood, plasma, or serum inactivated at 56 [deg]C for 30 minutes were good media, allowing prolonged survival of sporozoites. Normal serum slightly but definitely reduced infectivity. Temperatures up to 21 [deg]C allowed nearly quantitative survival of sporozoites for 3-4 hours. Temperatures of 26 [deg]C or higher markedly reduced infectivity within this period.Intravenous inoculation of sporozoites gave regular, intense infections. Intrahepatic injection was apparently nearly as good. Intramuscular, subcutaneous, and intraperitoneal inoculations resulted in irregular infections of mostly prolonged incubation period. Inoculations by stomach tube were negative. One of four orally inoculated chicks became infected with a prolonged prepatent period.A convenient method is described for routine quantitative induction of infection with sporozoites of Plasmodium gallinaceum.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32540/1/0000651.pd
Studies on malarial sporozoites. II. Effect of age and dosage of sporozoites on their infectiousness
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32533/1/0000635.pd
Community Engagement E-News - September 2019
Welcome Parkland\u27s New Volunteer Coordinator; Visit Parkland\u27s New Center for Community Engagement (C-134); Volunteer & Activities Fair, September 4; Join the Garden Hills Homework Club; Wesley Food Pantry at Parkland College; Project REA
Total Dose Effects on Single Event Transients in Digital CMOS and Linear Bipolar Circuits
This presentation discusses the effects of ionizing radiation on single event transients (SETs) in circuits. The exposure of integrated circuits to ionizing radiation changes electrical parameters. The total ionizing dose effect is observed in both complementary metal-oxide-semiconductor (CMOS) and bipolar circuits. In bipolar circuits, transistors exhibit grain degradation, while in CMOS circuits, transistors exhibit threshold voltage shifts. Changes in electrical parameters can cause changes in single event upset(SEU)/SET rates. Depending on the effect, the rates may increase or decrease. Therefore, measures taken for SEU/SET mitigation might work at the beginning of a mission but not at the end following TID exposure. The effect of TID on SET rates should be considered if SETs cannot be tolerated
Atypical Effect of Displacement Damage on LM124 Bipolar Integrated Circuits
International audienceLM124 operational amplifiers from three different manufacturers are irradiated with 60Co gamma rays and neutrons. During neutrons irradiation, one of the three integrated circuits exhibits an unexpected slew rates increase while its open loop gain and supply bias current follow the usual monotonic decrease as described in the literature. Analysis at circuit level shows that this phenomenon is due to an increase in the radiation-induced base current of the transistor used as buffer stage in the amplification chain. It is then demonstrated that a slight modification of the buffer transistor design, which is not implemented on the two other devices, enhances this phenomenon. Finally, the impact of the buffer transistor design on displacement damage and total ionizing dose response is investigated
A cross-national study on the antecedents of work–life balance from the fit and balance perspective
Drawing on the perceived work–family fit and balance perspective, this study investigates demands and resources as antecedents of work–life balance (WLB) across four countries (New Zealand, France, Italy and Spain), so as to provide empirical cross-national evidence. Using structural equation modelling analysis on a sample of 870 full time employees, we found that work demands, hours worked and family demands were negatively related to WLB, while job autonomy and supervisor support were positively related to WLB. We also found evidence that resources (job autonomy and supervisor support) moderated the relationships between demands and work–life balance, with high resources consistently buffering any detrimental influence of demands on WLB. Furthermore, our study identified additional predictors of WLB that were unique to some national contexts. For example, in France and Italy, overtime hours worked were negatively associated with WLB, while parental status was positively associated with WLB. Overall, the implications for theory and practice are discussed.Peer ReviewedPostprint (author's final draft
DNA microarray profiling of genes differentially regulated by the histone deacetylase inhibitors vorinostat and LBH589 in colon cancer cell lines
<p>Abstract</p> <p>Background</p> <p>Despite the significant progress made in colon cancer chemotherapy, advanced disease remains largely incurable and novel efficacious chemotherapies are urgently needed. Histone deacetylase inhibitors (HDACi) represent a novel class of agents which have demonstrated promising preclinical activity and are undergoing clinical evaluation in colon cancer. The goal of this study was to identify genes in colon cancer cells that are differentially regulated by two clinically advanced hydroxamic acid HDACi, vorinostat and LBH589 to provide rationale for novel drug combination partners and identify a core set of HDACi-regulated genes.</p> <p>Methods</p> <p>HCT116 and HT29 colon cancer cells were treated with LBH589 or vorinostat and growth inhibition, acetylation status and apoptosis were analyzed in response to treatment using MTS, Western blotting and flow cytometric analyses. In addition, gene expression was analyzed using the Illumina Human-6 V2 BeadChip array and Ingenuity<sup>® </sup>Pathway Analysis.</p> <p>Results</p> <p>Treatment with either vorinostat or LBH589 rapidly induced histone acetylation, cell cycle arrest and inhibited the growth of both HCT116 and HT29 cells. Bioinformatic analysis of the microarray profiling revealed significant similarity in the genes altered in expression following treatment with the two HDACi tested within each cell line. However, analysis of genes that were altered in expression in the HCT116 and HT29 cells revealed cell-line-specific responses to HDACi treatment. In addition a core cassette of 11 genes modulated by both vorinostat and LBH589 were identified in both colon cancer cell lines analyzed.</p> <p>Conclusion</p> <p>This study identified HDACi-induced alterations in critical genes involved in nucleotide metabolism, angiogenesis, mitosis and cell survival which may represent potential intervention points for novel therapeutic combinations in colon cancer. This information will assist in the identification of novel pathways and targets that are modulated by HDACi, providing much-needed information on HDACi mechanism of action and providing rationale for novel drug combination partners. We identified a core signature of 11 genes which were modulated by both vorinostat and LBH589 in a similar manner in both cell lines. These core genes will assist in the development and validation of a common gene set which may represent a molecular signature of HDAC inhibition in colon cancer.</p
Online and realtime dosimetry using optically stimulated luminescence
International audienceA new generation of Optically stimulated materials has been synthesized at the University Montpellier II. The very high sensitivity of these phosphors, the short time constant of the luminescence and the perfectly separated spectra enable many applications in real time and online dosimetry. Dosimetry can be considered as real-time when the dose change between two measurements is considered as low enough . For satellite applications, we have developed an integrated sensor to measure the dose received orbit by orbit. In radiotherapy, OSL has been used to control the dose deposited during intra-operative in-vivo irradiation. At CERN, we have proposed an online system to monitor the dose simultaneously in about one hundred locations inside the Compact Muon Solenoid (CMS) experiment
- …