5,157 research outputs found
Clouds of Small Things: Provisioning Infrastructure-as-a-Service from within Community Networks
Community networks offer a shared communication infrastructure where communities of citizens build and own open networks. While the IP connectivity of the networking devices is successfully achieved, the number of services and applications available from within the community network is typically small and the usage of the community network is often limited to providing Internet access to remote areas through wireless links. In this paper we propose to apply the principle of resource sharing of community networks, currently limited to the network bandwidth, to other computing resources, which leads to cloud computing in community networks. Towards this vision, we review some characteristics of community networks and identify potential scenarios for community clouds. We simulate a cloud computing infrastructure service and discuss different aspects of its performance in comparison to a commercial centralized cloud system. We note that in community clouds the computing resources are heterogeneous and less powerful, which affects the time needed to assign resources. Response time of the infrastructure service is high in community clouds even for a small number of resources since resources are distributed, but tends to get closer to that of a centralized cloud when the number of resources requested increases. Our initial results suggest that the performance of the community clouds highly depends on the community network conditions, but has some potential for improvement with network-aware cloud services. The main strength compared to commercial cloud services, however, is that community cloud services hosted on community-owned resources will follow the principles of community network and will be neutral and open
Asteroseismology of the GW Virginis stars SDSS J0349-0059 and VV 47
We present an asteroseismological study of SDSS J0349-0059 and VV 47 aimed
mainly at deriving their total mass on the basis of state-of-the-art PG 1159
evolutionary models. We compute adiabatic nonradial -mode pulsation periods
for PG 1159 evolutionary models with stellar masses ranging from to
0.741\ M_{\sun}, that take into account the complete evolution of the
progenitor stars. We first estimate a mean period spacing for both SDSS
J0349-0059 and VV 47. By comparing the observed period spacing with the
asymptotic period spacing we obtain M_{\star}\sim 0.569\ M_{\sun} for SDSS
J0349-0059 and M_{\star}\sim 0.523\ M_{\sun} for VV 47. If we compare the
observed period spacing with the average of the computed period spacings we
found M_{\star}\sim 0.535\ M_{\sun} for SDSS J0349-0059 and M_{\star}\sim
0.528 M_{\sun} for VV 47. Searching for the best period fit we found, in the
case of SDSS J0349-0059, an asteroseismological model with $M_{\star}= 0.542\
M_{\sun}T_{\rm eff}= 91\, 255\ P_{\rm rot}= 1/\Omega \sim 0.407$
days. The results presented in this work constitute a further step in the study
of GW Vir stars through asteroseismology in the frame of fully evolutionary
models of PG 1159 stars. In particular, once again it is shown the potential of
asteroseismology to derive stellar masses of PG 1159 stars with an
unprecedented precision.Comment: 13 pages, 16 figures, 6 tables. To be published in Astronomy and
Astrophysic
Effects of C-terminal truncations of the histone acetyltransferase p300 on the growth and gene expression patterns of human diffuse large B-cell lymphoma cell lines
Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkinâs B- cell lymphoma, accounting for about 30% of these lymphomas in the United States. Large-scale genome analyses of DLBCL have identified mutations in the related histone acetyltransferases (HATs) p300 and CBP in approximately 15% of patient samples and patient-derived cell lines. The research presented herein characterizes two human DLBCL cell lines, RC-K8 and SUDHL2, which express C-terminally truncated HAT domain-deficient p300 proteins, p300ÎC-1087 and p300 p300ÎC-820, respectively. It is shown that p300ÎC-820 localizes to sites of active transcription in the nucleus, interacts with NF-ÎșB transcription factor REL, weakly enhances REL-dependent transactivation, and has a half-life similar to wild-type p300. Results demonstrate that knockdown of p300ÎC-820 in SUDHL2 cells reduces cell proliferation in vitro. In RC-K8 cells, p300ÎC-1087 suppresses expression of the NF-ÎșB target genes A20 and IÎșBα, both of which are cytotoxic when overexpressed in RC-K8 cells. Microarray analysis of p300ÎC1087 knockdown compared to wild-type RC-K8 cells indicated that p300ÎC-1087 suppresses an NF-ÎșB gene expression program and activates a MYC gene expression program in RC-K8 cells. Bioinformatic analysis demonstrated that cancer cell linesâ regardless of tissue typeâwith truncating p300 mutations have altered expression of a MYC target gene set as compared to cancer cell lines with wild-type p300/CBP. Taken together, this research indicates that p300 truncations contribute to cell growth in DLBCL by modifying the transcriptional output of two lymphoid cell-specific oncoproteins, NF- ÎșB and MYC, to optimal levels and suggests that p300 truncating mutations similarly modify the activity of oncogenic drivers in other cancer cell types. Based on this work, p300 truncation is proposed to represent a new class of oncogenic mutation that serves to optimize the activity of context-specific oncogenic transcription factors, and it is suggested that such oncogenic mutations be termed âcancer modifyingâ mutations.2017-09-30T00:00:00
A Study of Multiple Predictors of Cognitive Fatigue in Individuals with Multiple Sclerosis
Persons with multiple sclerosis (PwMS) commonly experience cognitive fatigue (CF), defined as a decrease in cognitive performance over a sustained activity and measured objectively or subjectively. In the present research, we evaluated the extent to which depression, anxiety, information processing speed, sleep quality, and disease severity predict subjective and objective CF, in a sample of 55 PwMS (37 females, M = 44.23). Although no statistically significant predictors of objective CF were demonstrated, all variables predicted subjective CF, R2adj = .384 [F (6, 40) = 5.783, p = .0002]. In particular, depression and information processing speed were found to be significant predictors of subjective CF when controlling for anxiety, sleep quality, and disease severity. Findings are discussed in the context of treating subjective CF through treatment of these affective and cognitive factors (e.g., through psychotherapy)
Alien Registration- Shaw, Leila M. (Auburn, Androscoggin County)
https://digitalmaine.com/alien_docs/30396/thumbnail.jp
Image Memory for Hyperpalatable Foods in University Aged Females
Hyperpalatable foods are high in sugar and/or fat and highly processed. These foods increase dopamine in the brain similar to other rewards, such as drugs of abuse, producing pleasure and an enhanced drive to consume them. Undergraduate students (n = 44) completed an explicit memory task where they were asked if they recalled various types of food (high sugar, high fat, sugar+fat, fruits, vegetables and breads) and non-food images. Questionnaires evaluating eating patterns were also completed. It was hypothesized that hyperpalatable foods would be recalled better and faster than less-palatable foods or non-food images. The study found that hyperpalatable foods, especially high sugar and high fat foods, were recalled significantly faster than less palatable foods. Results also revealed significantly fewer false alarms for high sugar, high fat, and sugar+fat foods. Thus, hyperpalatable foods appear to create stronger memories, which may contribute to stronger motivation and consumption drives
ASSESSING THE IMPACT OF EMERGING CONTAMINANTS ON ANAEROBIC MICROBIAL COMMUNITIES
The impact of emerging contaminants on anaerobic microbial communities is critical an
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