21,415 research outputs found
Recommended from our members
e-Government awareness among the techno-disadvantaged in the United States
This exploratory research focuses on awareness among techno-disadvantaged citizens in the United States. Specifically, we address whether awareness is associated with visitation and whether there are differences between those who are aware and those who are not aware. Following up on on a theory-based community initiative designed to improve computer literacy and access to information and communication technologies (ICT) for members of an underserved public housing community, a survey was undertaken. The results indicate that awareness is associated with visitation. Differences in demographic characterisitics, perceived ease of use (PEOU), and perceived access barriers between those who are aware of e-government websites, and those who are not, were found. While nearly half of the respondents are neither aware of nor have visited e-government websites, a slight majority is partaking of e-government services. We identify directions for future research and conclude by emphasizing the value of a theory-based community initiative to improve computer literacy, provide access to ICT, and advance e-government inclusion
Are plants with anti-cancer activity resistant to crown gall? : A test of hypothesis
The Crown gall tumour assay (CGTA) is one of several bench top bioassays recommended for the rapid screening of plants with anti-cancer activity. The rationale for the use of the bioassay is that the tumorogenic mechanism initiated in plant tissues by _Agrobacterium tumefaciens_ is in many ways similar to that of animals. Several plant species with anti-cancer activity have already been discovered using this bioassay. However till date no explicit test of an association between anti-cancer activity of plants and their resistance to crown gall formation has been demonstrated. Demonstration of an association could have exploratory potential when searching for plants with anti-cancer activity. In this paper, we determined whether or not a statistically significant association between crown gall resistance and anti-cancer activity exists in plants found in existing published data sets. Our results indicate that plants with anti-cancer activity have a higher proportion of their species resistant to crown gall formation compared to a random selection of plants. We discuss the implications of our results especially when prospecting for newer sources of anti-cancer activity in plants
Information Communication and Technology for Political Communication Ethics
The purpose of the research is to know about political communication ethics in a demonstration. Political communication ethics is one of the efforts to prevent anarchic actions in demonstrations. In a demonstration, there are ways of expressing opinions to understand. Anarchic demonstrations can cause the goal of the demonstration not to be achieved. This research used a qualitative method with a descriptive approach. In this research, researchers use data analysis to explain political communication ethics in the demonstration in Indonesia. The results of this study show that in political communication ethics there is politeness. Therefore, demonstrating is required to understand ethics in expressing opinions. This political ethic is influenced by social, cultural, political, and economic factors developed in society. An ethical demonstration can lead to the achievement of the objectives of the demonstration. The result of this research's discussion is that political communication ethics adhere to politeness, so that political communication ethics requires political communication actors to understand the social, cultural, political, and economic influences on political communication. By understanding the ethics of political communication, it will create a peaceful demonstration
Efficient Dynamic Approximate Distance Oracles for Vertex-Labeled Planar Graphs
Let be a graph where each vertex is associated with a label. A
Vertex-Labeled Approximate Distance Oracle is a data structure that, given a
vertex and a label , returns a -approximation of
the distance from to the closest vertex with label in . Such
an oracle is dynamic if it also supports label changes. In this paper we
present three different dynamic approximate vertex-labeled distance oracles for
planar graphs, all with polylogarithmic query and update times, and nearly
linear space requirements
Fossil biomass preserved as graphitic carbon in a late paleoproterozoic banded iron formation metamorphosed at more than 550°C
Metamorphism is thought to destroy microfossils, partly through devolatilization and graphitization of biogenic organic matter. However, the extent to which there is a loss of molecular, elemental and isotope signatures from biomass during high-temperature metamorphism is not clearly established. We report on graphitic structures inside and coating apatite grains from the c. 1850 Ma Michigamme silicate banded iron formation from Michigan, metamorphosed above 550°C. Traces of N, S, O, H, Ca and Fe are preserved in this graphitic carbon and X-ray spectra show traces of aliphatic groups. Graphitic carbon has an expanded lattice around 3.6 Å, forms microscopic concentrically-layered and radiating polygonal flakes and has homogeneous δ13C values around −22‰, identical to bulk analyses. Graphitic carbon inside apatite is associated with nanometre-size ammoniated phyllosilicate. Precursors of these metamorphic minerals and graphitic carbon originated from ferruginous clayrich sediments with biomass. We conclude that graphite coatings and inclusions in apatite grains indicate fluid remobilization during amphibolite-facies metamorphism of precursor biomass. This new evidence fills in observational gaps of metamorphosed biomass into graphite and supports the existence of biosignatures in the highly metamorphosed iron formation from the Eoarchean Akilia Association, which dates from the beginning of the sedimentary rock record
Simultaneous production of raw starch degrading highly thermostable a-amylase and lactic acid by Lactobacillus fermentum 04BBA19
The widely used thermostable amylases were produced long time ago from Bacillus genus. Although, lactic acid bacteria (LAB) fermentation presents several advantages including the reduction of growth of pathogenic microorganisms, no study has yet reported thermostable amylases from lactic acid bacteria. An amylolytic LAB, Lactobacillus fermentum (04BBA19) isolated from starchy wastes of a soil sample from the western region of Cameroon was studied for amylase and lactic acid production. The bacterium exhibited maximal amylase and lactic acid production at temperature of 45°C, and within pH range of 4.0 to 6.5. Upon the optimization of various environmental and cultural conditions the yield of amylase and lactic acid reached 732.3±0.4 U/ml and 53.2±0.7 g/L respectively in fermented broth after 48 h of culture. The enzyme was identified as α-amylase, with a very high thermostability revealed by the retention of 100% of original activity after pre-incubation for 30 min at 80°C. The stability was improved significantly with the addition of 0.1% (w/v) CaCl2.2H2O; the half life of the enzyme in these conditions was 6 h at 80°C. Owing to its aptitude to exhibit a simultaneous production of thermostable amylase and lactic acid, L. fermentum (04BBA19) appeared as a potential candidate for the making of high density gruel from starchy material.Key words: Lactic acid bacteria, thermostable a-amylase, lactic acid, fermentation, high density gruel
Mind the Gap: A Study in Global Development through Persistent Homology
The Gapminder project set out to use statistics to dispel simplistic notions
about global development. In the same spirit, we use persistent homology, a
technique from computational algebraic topology, to explore the relationship
between country development and geography. For each country, four indicators,
gross domestic product per capita; average life expectancy; infant mortality;
and gross national income per capita, were used to quantify the development.
Two analyses were performed. The first considers clusters of the countries
based on these indicators, and the second uncovers cycles in the data when
combined with geographic border structure. Our analysis is a multi-scale
approach that reveals similarities and connections among countries at a variety
of levels. We discover localized development patterns that are invisible in
standard statistical methods
Photoacoustic imaging with a multi-view Fabry-Perot scanner
Planar Fabry-Pérot (FP) ultrasound sensor arrays have been used to produce in-vivo photoacoustic images of
high quality due to their broad detection bandwidth, small element size, and dense spatial sampling. However
like all planar arrays, FP sensors suffer from the limited view problem. Here, a multi-angle FP sensor system is
described that mitigates the partial view effects of a planar FP sensor while retaining its detection advantages.
The possibility of improving data acquisition speed through the use of sub-sampling techniques is also explored.
The capabilities of the system are demonstrated with 3D images of pre-clinical targets
Forecasting the severity of the Newfoundland iceberg season using a control systems model
The iceberg hazard for the Grand Banks area to the east of Newfoundland varies dramatically from one year to the next. In some years no icebergs penetrate south of 48°N, while in others well over 1000 icebergs enter the main shipping lanes between Europe and NE North America. Advance knowledge of this seasonal hazard would have major implications for ship routing, as well as the resources required for maintaining an effective ice hazard service. Here, a Windowed Error Reduction Ratio control system identification approach is used to forecast the severity of the 2018 iceberg season off Newfoundland, in terms of the predicted number of icebergs crossing 48°N, as well as to hindcast iceberg numbers for 2017. The best estimates are for 766 ± 297 icebergs crossing 48°N before the end of September 2017 and 685 ± 207 for 2018. These are both above the recent observed average of 592 icebergs for that date, and substantially so for 2017. Given the bimodal nature of the annual iceberg number, this means that our predictions for both 2017 and 2018 are for a high iceberg season, with a 71% level of confidence. However, it is most likely that the 2018 iceberg numbers will be somewhat less than 1000, while our higher hindcast for 2017 is consistent with the observed level of 1008. Our verification analysis, covering the 20-year period up to 2016, shows our model's correspondence to the high or low nature of the 48°N iceberg numbers is statistically robust to the 0.05% level, with a skill level of 80%
- …