639 research outputs found
A program to evaluate a control system based on feedback of aerodynamic pressure differentials, part 1
The use of pressure differentials in a flight control system was evaluated. The pressure profile around the test surface was determined using two techniques: (1) windtunnel data (actual); and (2) NASA/Langley Single Element Airfoil Computer Program (theoretical). The system designed to evaluate the concept of using pressure differentials is composed of a sensor drive and power amplifiers, actuator, position potentiometer, and a control surface. The characteristics (both desired and actual) of the system and each individual component were analyzed. The desired characteristics of the system as a whole are given. The flight control system developed, the testing procedures and data reduction methods used, and theoretical frequency response analysis are described
Reference gene alternatives to Gapdh in rodent and human heart failure gene expression studies
<p>Abstract</p> <p>Background</p> <p>Quantitative real-time RT-PCR (RT-qPCR) is a highly sensitive method for mRNA quantification, but requires invariant expression of the chosen reference gene(s). In pathological myocardium, there is limited information on suitable reference genes other than the commonly used <it>Gapdh </it>mRNA and <it>18S </it>ribosomal RNA. Our aim was to evaluate and identify suitable reference genes in human failing myocardium, in rat and mouse post-myocardial infarction (post-MI) heart failure and across developmental stages in fetal and neonatal rat myocardium.</p> <p>Results</p> <p>The abundance of <it>Arbp</it>, <it>Rpl32</it>, <it>Rpl4</it>, <it>Tbp</it>, <it>Polr2a</it>, <it>Hprt1</it>, <it>Pgk1</it>, <it>Ppia </it>and <it>Gapdh </it>mRNA and <it>18S </it>ribosomal RNA in myocardial samples was quantified by RT-qPCR. The expression variability of these transcripts was evaluated by the geNorm and Normfinder algorithms and by a variance component analysis method. Biological variability was a greater contributor to sample variability than either repeated reverse transcription or PCR reactions.</p> <p>Conclusions</p> <p>The most stable reference genes were <it>Rpl32</it>, <it>Gapdh </it>and <it>Polr2a </it>in mouse post-infarction heart failure, <it>Polr2a</it>, <it>Rpl32 </it>and <it>Tbp </it>in rat post-infarction heart failure and <it>Rpl32 </it>and <it>Pgk1 </it>in human heart failure (ischemic disease and cardiomyopathy). The overall most stable reference genes across all three species was <it>Rpl32 </it>and <it>Polr2a</it>. In rat myocardium, all reference genes tested showed substantial variation with developmental stage, with <it>Rpl4 </it>as was most stable among the tested genes.</p
Ovine herpesvirus-2 encoded microRNAs target virus genes involved in virus latency
Herpesviruses encode miRNAs that target both virus and host genes; however their role in herpesvirus biology is poorly understood. We previously identified eight miRNAs encoded by OvHV-2; the causative agent of malignant catarrhal fever (MCF) and have now investigated the role of these miRNAs in regulating expression of OvHV-2 genes that play important roles in virus biology. ORF 20 (cell cycle inhibition), ORF 50 (reactivation) and ORF 73 (latency maintenance) each contain predicted targets for several OvHV-2 miRNAs. Co-transfection of miRNA mimics with luciferase reporter constructs containing the predicted targets showed the 5’ UTRs of ORF 20 and ORF 73 contain functional targets for ovhv-miR-2 and ovhv2-miR-8 respectively, and the 3’UTR of ORF 50 contains a functional target for ovhv2-miR-5. Transfection of BJ1035 cells (an OvHV-2 infected bovine T cell line) with the relevant miRNA mimic resulted in a significant decrease in ORF 50 and a smaller but non-significant decrease in ORF 20. However, we were unable to demonstrate a decrease in ORF 73. MCF is a disease of dysregulated lymphocyte proliferation, miRNA inhibition of ORF 20 expression may play a role in this aberrant lymphocyte proliferation. The proteins encoded by ORFs 50 and 73 play opposing roles in latency, it has been hypothesized that miRNA-induced inhibition of virus genes acts to ensure that fluctuations in virus mRNA levels do not result in reactivation in conditions that are unfavourable for viral replication, our data would support this hypothesis
Different routes, common directions? Activation policies for young people in Denmark and the UK
This article analyses and compares the development of activation policies for young people in Denmark and the UK from the mid-1990s. Despite their diverse welfare traditions and important differences in the organisation and delivery of benefits and services for the unemployed, both countries have recently introduced large-scale compulsory activation programmes for young people. These programmes share a number of common features, especially a combination of strong compulsion and an apparently contradictory emphasis on client-centred training and support for participants. The suggested transition from the ‘Keynesian welfare state’ to the ‘Schumpeterian workfare regime’ is used as a framework to discuss the two countries’ recent moves towards activation. It is argued that while this framework is useful in explaining the general shift towards active labour-market policies in Europe, it alone cannot account for the particular convergence of the Danish and British policies in the specific area of youth activation. Rather, a number of specific political factors explaining the development of policies in the mid-1990s are suggested. The article concludes that concerns about mass youth unemployment, the influence of the ‘dependency culture’ debate in various forms, cross-national policy diffusion and, crucially, the progressive re-engineering of compulsory activation by strong centre-left governments have all contributed to the emergence of policies that mix compulsion and a commitment to the centrality of work with a ‘client-centred approach’ that seeks to balance more effective job seeking with human resource development. However, attempts to combine the apparently contradictory concepts of ‘client-centredness’ and compulsion are likely to prove politically fragile, and both countries risk lurching towards an increasingly workfarist approach
Current management of limited-stage SCLC and CONVERT trial impact:Results of the EORTC Lung Cancer Group survey
Objectives: The CONVERT trial showed that twice-daily (BD) concurrent chemoradiotherapy should continue tobe considered the standard of care in localised LS-SCLC. A survey was conducted to assess the impact of theCONVERT trial in clinical practice and to identify any relevant research questions for future trials in this setting.Methods and materials: An EORTC Group online survey of LS-SCLC practice was distributed to the EORTC LCGand to members of several European thoracic oncology societies between April and December 2018.Results: 198 responses were analysed. The majority of respondents (88%, n=174) were aware of the CONVERTtrial. Radiation oncologists comprised 56% of all respondents. Once-daily (OD) radiotherapy is still the mostcommonly used regimen, however the use of concurrent BD radiotherapy increased after the publication ofCONVERT (n=59/186, 32% prior to and n=78/187, 42% after the publication, p=0.053). The main reasonsfor not implementing BD after the CONVERT publication were logistical issues (n=88, 44%), inconvenience forpatients (n=56, 28%), and the absence of a statistical survival difference between the two arms in CONVERT(n=38, 19%). Brain MRI was used by 28% during staging but more than half (60%) of the respondents did notroutinely image the brain during follow-up. The main research questions of interest in LS-SCLC were 1) integratingnovel targeted therapies-immunotherapies (n=160, 81%), 2) PCI (+/- hippocampal sparing) vs. MRIsurveillance (n=140, 71%) and, 3) biomarker driven trials (n=92, 46%).Conclusion: Once daily radiotherapy (60–66 Gy in 30–33 fractions) remains the most prescribed radiotherapyfractionation, despite the findings suggested by the CONVERT trial.info:eu-repo/semantics/publishe
Relationship between the Social Cognition and Object Relations Scale (SCORS) and attachment style in a clinical sample
This present study examined the relationship between the Social Cognition and Object Relations Scale (SCORS) and two measures of adult attachment: the Relationship Questionnaire (RQ) and the Experiences in Close Relationships Questionnaire‐Revised (ECR‐R). Forty‐five patients (76% female) at a university‐based outpatient treatment clinic participated in this study. We hypothesized that higher levels of attachment security would be associated with higher, more adaptive ratings on the SCORS variables. Results indicated that the SCORS Self‐Esteem (SE) variable was significantly positively related to the RQ's Secure Attachment ratings and negatively related with the ECR‐R's Anxious Attachment scale. Additionally, negative trends were noted between SE and the RQ's Fearful and Preoccupied Attachment scores. The SCORS Emotional Investments in Relationships and Affective Quality of Representations variables were associated with higher Secure scores and lower, more maladaptive Preoccupied scores on the RQ. It was also associated with greater attachment anxiety as measured by the ECR‐R. Using both clinician (SCORS) and participant‐rated measures (ECR‐R and RQ), this study provides further understanding on how object representations and attachment style relate within a clinical sample. Results are discussed in light of prior research examining relationships between object relations and adult attachments, and clinical implications are also reviewed. Copyright © 2010 John Wiley & Sons, Ltd. Key Practitioner Message: • Individuals with higher levels of attachment anxiety may enter therapy with more self‐image problems. • Individuals with higher levels of attachment anxiety may enter therapy with more maladaptive expectations about relationships. • Patients who endorse high levels of attachment anxiety (e.g., fearful and preoccupied) may be more likely to present with Axis II complaints. • Examining a patient's attachment style and object relations using different measures of assessment (e.g., explicit and implicit) can help gain a deeper and more comprehensive understanding of a patient.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88074/1/721_ftp.pd
The use of information theory in evolutionary biology
Information is a key concept in evolutionary biology. Information is stored
in biological organism's genomes, and used to generate the organism as well as
to maintain and control it. Information is also "that which evolves". When a
population adapts to a local environment, information about this environment is
fixed in a representative genome. However, when an environment changes,
information can be lost. At the same time, information is processed by animal
brains to survive in complex environments, and the capacity for information
processing also evolves. Here I review applications of information theory to
the evolution of proteins as well as to the evolution of information processing
in simulated agents that adapt to perform a complex task.Comment: 25 pages, 7 figures. To appear in "The Year in Evolutionary Biology",
of the Annals of the NY Academy of Science
Environmental Effects on the Metal Enrichment of Low Mass Galaxies in Nearby Clusters
In this paper we study the chemical history of low-mass star-forming (SF)
galaxies in the local Universe clusters Coma, A1367, A779, and A634. The aim of
this work is to search for the imprint of the environment on the chemical
evolution of these galaxies. Galaxy chemical evolution is linked to the star
formation history (SFH), as well as to the gas interchange with the
environment, and low-mass galaxies are well known to be vulnerable systems to
environmental processes affecting both these parameters. For our study we have
used spectra from the SDSS-III DR8. We have examined the mass-metallicity
relation of cluster galaxies finding well defined sequences. The slope of these
sequences, for galaxies in low-mass clusters and galaxies at large
cluster-centric distances, follows the predictions of recent hydrodynamic
models. A flattening of this slope has been observed for galaxies located in
the core of the two more massive clusters of the sample, principally in Coma,
suggesting that the imprint of the cluster environment on the chemical
evolution of SF galaxies should be sensitive to both the galaxy mass and the
host cluster mass. The HI gas content of Coma and A1367 galaxies indicate that
low-mass SF galaxies, located at the core of these clusters, have been severely
affected by ram-pressure stripping. The observed mass-dependent enhancement of
the metal content of low-mass galaxies in dense environments seems plausible,
according to hydrodynamic simulations. This enhanced metal enrichment could be
produced by the combination of effects such as wind reaccretion, due to
pressure cofinement by the intra-cluster medium (ICM), and the truncation of
gas infall, as a result of the ram-pressure stripping. Thus, the properties of
the ICM should play an important role in the chemical evolution of low-mass
galaxies in clusters.Comment: ApJ accepted, 31 pages, 13 figure
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