6,460 research outputs found
"Investment in Innovation, Corporate Governance and Employment: Is Prosperity Sustainable in the United States?"
Over the past decades foreign enterprises have gained competitive advantage over U.S. industrial corporations not by paying lower wages than American companies pay, Lazonick and O'Sullivan argue, but by developing and utilizing broader and deeper skill bases than American companies do. Since the 1970s corporate America has become obsessed with shedding employees to cut costs and with distributing revenue to stockholders. However, the way for it to regain its competitive edge and thus to restore the promise of secure and remunerative employment for its workers is to reform its system of governance. It must reject organizational segmentation and extraction of short-term returns and instead emphasize organizational integration and long-term value creation through financial commitment to investment in the collective and cumulative learning that is the foundation of industrial innovation.
High-throughput DNA sequencing to survey bacterial histidine and tyrosine decarboxylases in raw milk cheeses
peer-reviewedBackground
The aim of this study was to employ high-throughput DNA sequencing to assess the incidence of bacteria with biogenic amine (BA; histamine and tyramine) producing potential from among 10 different cheeses varieties. To facilitate this, a diagnostic approach using degenerate PCR primer pairs that were previously designed to amplify segments of the histidine (hdc) and tyrosine (tdc) decarboxylase gene clusters were employed. In contrast to previous studies in which the decarboxylase genes of specific isolates were studied, in this instance amplifications were performed using total metagenomic DNA extracts.
Results
Amplicons were initially cloned to facilitate Sanger sequencing of individual gene fragments to ensure that a variety of hdc and tdc genes were present. Once this was established, high throughput DNA sequencing of these amplicons was performed to provide a more in-depth analysis of the histamine- and tyramine-producing bacteria present in the cheeses. High-throughput sequencing resulted in generation of a total of 1,563,764 sequencing reads and revealed that Lactobacillus curvatus, Enterococcus faecium and E. faecalis were the dominant species with tyramine producing potential, while Lb. buchneri was found to be the dominant species harbouring histaminogenic potential. Commonly used cheese starter bacteria, including Streptococcus thermophilus and Lb. delbreueckii, were also identified as having biogenic amine producing potential in the cheese studied. Molecular analysis of bacterial communities was then further complemented with HPLC quantification of histamine and tyramine in the sampled cheeses.
Conclusions
In this study, high-throughput DNA sequencing successfully identified populations capable of amine production in a variety of cheeses. This approach also gave an insight into the broader hdc and tdc complement within the various cheeses. This approach can be used to detect amine producing communities not only in food matrices but also in the production environment itself.This work was funded by the Department of Agriculture, Food and the Marine under the Food Institutional Research Measure through the
‘Cheeseboard 2015’ project. Daniel J. O’Sullivan is in receipt of a Teagasc Walsh Fellowship, Grant Number: 2012205
Robust quantum state engineering through coherent localization in biased-coin quantum walks
We address the performance of a coin-biased quantum walk as a generator for
non-classical position states of the walker. We exploit a phenomenon of
coherent localisation in the position space --- resulting from the choice of
small values of the coin parameter and assisted by post-selection --- to
engineer large-size coherent superpositions of distinguishable position states
of the walker. The protocol that we design appears to be remarkably robust
against both the actual value taken by the coin parameter and strong
dephasing-like noise acting on the spatial degree of freedom. We finally
illustrate a possible linear-optics implementation of our proposal, suitable
for both bulk and integrated-optics platforms.Comment: 7 pages, 7 figure
"Corporate Governance and Corporate Employment: Is Prosperity Sustainable in the United States?"
Temporal and spatial differences in microbial composition during the manufacture of a Continental-type cheese
peer-reviewedWe sought to determine if the time, within a production day, that a cheese is manufactured has an influence on the microbial community present within that cheese. To facilitate this, 16S rRNA amplicon sequencing was used to elucidate the microbial community dynamics of brine salted Continental-type cheese in cheeses produced early and late in the production day. Differences in microbial composition of the core and rind of the cheese were also investigated.
Throughout ripening, it was apparent that late production day cheeses had a more diverse microbial population than their early day equivalents. Spatial variation between the cheese core and rind was also noted in that cheese rinds were found to initially have a more diverse microbial population but thereafter the opposite was the case. Interestingly, the genera Thermus, Pseudoalteromonas and Bifidobacterium, not routinely associated with a Continental-type cheese produced from pasteurised milk were detected. The significance, if any, of the presence of these genera will require further attention. Ultimately, the use of high throughput sequencing has facilitated a novel and detailed analysis of the temporal and spatial distribution of microbes in this complex cheese system and established that the period during a production cycle at which a cheese is manufactured can influence its microbial composition.This work was funded by the Department of Agriculture, Food and the Marine under the Food Institutional Research Measure through the ‘Cheeseboard 2015’ project. Daniel J. O’Sullivan is in receipt of a Teagasc Walsh Fellowship, Grant Number: 201220
Trending Paths: A New Semantic-level Metric for Comparing Simulated and Real Crowd Data
We propose a new semantic-level crowd evaluation metric in this paper. Crowd simulation has been an active and important area for several decades. However, only recently has there been an increased focus on evaluating the fidelity of the results with respect to real-world situations. The focus to date has been on analyzing the properties of low-level features such as pedestrian trajectories, or global features such as crowd densities. We propose the first approach based on finding semantic information represented by latent Path Patterns in both real and simulated data in order to analyze and compare them. Unsupervised clustering by non-parametric Bayesian inference is used to learn the patterns, which themselves provide a rich visualization of the crowd behavior. To this end, we present a new Stochastic Variational Dual Hierarchical Dirichlet Process (SV-DHDP) model. The fidelity of the patterns is computed with respect to a reference, thus allowing the outputs of different algorithms to be compared with each other and/or with real data accordingly. Detailed evaluations and comparisons with existing metrics show that our method is a good alternative for comparing crowd data at a different level and also works with more types of data, holds fewer assumptions and is more robust to noise
New insights into the evolution of the FR I radio galaxy 3C 270 (NGC 4261) from VLA and GMRT radio observations
We present Giant Metrewave Radio Telescope (GMRT) 240 MHz observations of the
nearby luminous FR I radio source 3C 270, in the group-central elliptical NGC
4261. Combining these data with reprocessed Very Large Array (VLA) 1.55 and 4.8
GHz observations, we produce spectral index maps that reveal a constant
spectral index along the jets and a gradual steepening from the ends of the
jets through the lobes towards the nucleus. A Jaffe & Perola (JP) model fitted
to the integrated spectrum of the source gives an asymptotic low-frequency
index of , while JP models fitted to the
observed spectral index trend along the lobes allow us to estimate radiative
ages of Myr and Myr for the west and east lobes respectively.
Our age estimates are a factor of two lower than the 75-Myr upper limit derived
from X-ray data (O'Sullivan et al. 2011). We find unlikely the scenario of an
early supersonic phase in which the lobe expanded into the ISM at approximately
Mach 6 (3500 km s), and suggest that either the source underwent
multiple AGN outbursts with possible large changes in jet power, or possibly
that the source age that we find is due to a backflow that transports young
electrons from the jet tips through the lobes toward the nucleus relatively
quickly. We calculate that in the lobes the energy ratio of non-radiating to
radiating particles is indicating significant gas entrainment. If
the lobes are in pressure balance with their surroundings, the total energy
required to heat the entrained material is erg, 40% of the
total enthalpy of the lobes.Comment: 14 pages, 11 figures, 8 tables. Accepted for publication by MNRAS.
Revised throughout in response to referee's comment
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