Use of carbon monoxide packaging for improving the shelf-life of pork

The effects of packaging atmosphere (aerobic, vacuum, MAP, or MAP-CO) on pork chops were investigated. Eighty pork loins (40 injected, 40 uninjected) of normal inherent muscle quality were used to evaluate the color, microbial growth, rancidity, purge, and sensory quality of pork chops in four different packaging environments during refrigerated storage. All treatments were evaluated 3 times/week for 5 weeks during storage at 0-20C. Hunter a* values (for both injected and uninjected chops) were significantly (P\u3c 0.001) higher in MAP-CO (11.25) than the aerobic (6.93), MAP (3.80), or the vacuum (2.74) packages. Sensory evaluations supported this, as color values (100 point scale) were also higher for chops in MAP-CO (85.91) than aerobic (62.47), MAP (42.42), and vacuum (44.52) packages. Rancidity (TBARS) was significantly (P\u3c 0.001) reduced during storage by MAP-CO (0.118) as compared to the aerobic packages (0.365). However, MAP-CO did not significantly reduce microbial growth or purge loss. The results showed that carbon monoxide significantly improved color stability and sensory characteristics of pork in modified atmosphere packages during refrigerated storage

Discriminative Clustering by Regularized Information Maximization

Is there a principled way to learn a probabilistic discriminative classifier from an unlabeled data set? We present a framework that simultaneously clusters the data and trains a discriminative classifier. We call it Regularized Information Maximization (RIM). RIM optimizes an intuitive information-theoretic objective function which balances class separation, class balance and classifier complexity. The approach can flexibly incorporate different likelihood functions, express prior assumptions about the relative size of different classes and incorporate partial labels for semi-supervised learning. In particular, we instantiate the framework to unsupervised, multi-class kernelized logistic regression. Our empirical evaluation indicates that RIM outperforms existing methods on several real data sets, and demonstrates that RIM is an effective model selection method

Exporters to countries that value CEO power will have more powerful CEOs

When in Rome, look like Caesar: legitimacy in the eyes of the customers is important, write Ryan Krause, Igor Filatotchev and Garry Bruto

Crowdclustering

Is it possible to crowdsource categorization? Amongst the challenges: (a) each worker has only a partial view of data, (b) different workers may have different clustering criteria and may produce different numbers of categories, (c) the underlying category structure may be hierarchical. We propose a Bayesian model of how workers may approach clustering and show how one may infer clusters/categories, as well as worker parameters, using this model. Our experiments, carried out on large collections of images, suggest that Bayesian crowdclustering works well and may be superior to single-expert annotations

Target of Opportunity Multipoint in Situ Measurements with Falconsat-2

This paper describes the FalconSAT-2 mission objectives to take advantage of targets of opportunity to make multipoint in situ measurements of ionospheric plasma depletions simultaneously with other spacecraft. Because these plasma depletions are known to interfere with radio transmissions over a broad range of frequencies, including 100-1000 MHz, the international space weather community is investigating the instigation, temporal evolution, and spatial propagation of these structures in the hopes that a prediction tool may be developed to warn operators of outages in communications or navigation. FalconSAT-2 will be launched into a low altitude (360 km), medium inclination (52 degrees) orbit with sensors designed to measure in situ suprathermal plasma spectra at a rate of 10 samples per second. The primary mission objectives are to 1) investigate F region ionospheric plasma depletion morphology relative to geomagnetic activity, and 2) demonstrate the utility of the Miniature Electrostatic Analyzer (MESA) in measuring energy-resolved spectra of ionospheric electrons over a dynamic range such that plasma density depletions down to 0.1% of the background may be resolved at a rate of 10 Hz. Simultaneous in situ multipoint observations of ionospheric plasma depletions are designated as a secondary objective since FalconSAT-2 consists of a single spacecraft, and opportunities to make these simultaneous measurements with other spacecraft in compatible orbits are not in our control. Both deep and shallow bubbles, frequently observed in the pre- and post-midnight sectors, respectively [Singh at al., 1997], are known to exhibit magnetic field-aligned behavior [Fagundes et al., 1997]; thus, there is the expectation (to first order) that multiple spacecraft entering a magnetic flux tube simultaneously have the opportunity to observe a depletion structure at different points within the structure. This observation would provide insight into the plasma depletion extent along the field line. Other conjunction types, such as non-simultaneous intersection of a flux tube or crossing of orbital paths simultaneously in different magnetic flux tubes, provide insight into other aspects of depletion structure, such as constraining the plasma depletion extent and propagation speed along the magnetic field line, or plasma depletion vertical extent. With this paper, a statistical analysis of the probability that FalconSAT-2 will intersect a magnetic flux tube during eclipse simultaneously with other spacecraft capable of measuring thermal electrons is presented

Biochemical and structural characterization of alanine racemase from Bacillus anthracis (Ames)

<p>Abstract</p> <p>Background</p> <p><it>Bacillus anthracis </it>is the causative agent of anthrax and a potential bioterrorism threat. Here we report the biochemical and structural characterization of <it>B. anthracis </it>(Ames) alanine racemase (Alr_<it>Bax</it>), an essential enzyme in prokaryotes and a target for antimicrobial drug development. We also compare the native Alr_{<it>Bax </it>}structure to a recently reported structure of the same enzyme obtained through reductive lysine methylation.</p> <p>Results</p> <p><it>B. anthracis </it>has two open reading frames encoding for putative alanine racemases. We show that only one, <it>dal1</it>, is able to complement a D-alanine auxotrophic strain of <it>E. coli</it>. Purified Dal1, which we term Alr_<it>Bax</it>, is shown to be a dimer in solution by dynamic light scattering and has a V_maxfor racemization (L- to D-alanine) of 101 U/mg. The crystal structure of unmodified Alr_{<it>Bax </it>}is reported here to 1.95 Å resolution. Despite the overall similarity of the fold to other alanine racemases, Alr_{<it>Bax </it>}makes use of a chloride ion to position key active site residues for catalysis, a feature not yet observed for this enzyme in other species. Crystal contacts are more extensive in the methylated structure compared to the unmethylated structure.</p> <p>Conclusion</p> <p>The chloride ion in Alr_{<it>Bax </it>}is functioning effectively as a carbamylated lysine making it an integral and unique part of this structure. Despite differences in space group and crystal form, the two Alr_{<it>Bax </it>}structures are very similar, supporting the case that reductive methylation is a valid rescue strategy for proteins recalcitrant to crystallization, and does not, in this case, result in artifacts in the tertiary structure.</p

RNA interference of gonadotropin-inhibitory hormone gene induces arousal in songbirds.

Gonadotropin-inhibitory hormone (GnIH) was originally identified in quail as a hypothalamic neuropeptide inhibitor of pituitary gonadotropin synthesis and release. However, GnIH neuronal fibers do not only terminate in the median eminence to control anterior pituitary function but also extend widely in the brain, suggesting it has multiple roles in the regulation of behavior. To identify the role of GnIH neurons in the regulation of behavior, we investigated the effect of RNA interference (RNAi) of the GnIH gene on the behavior of white-crowned sparrows, a highly social songbird species. Administration of small interfering RNA against GnIH precursor mRNA into the third ventricle of male and female birds reduced resting time, spontaneous production of complex vocalizations, and stimulated brief agonistic vocalizations. GnIH RNAi further enhanced song production of short duration in male birds when they were challenged by playbacks of novel male songs. These behaviors resembled those of breeding birds during territorial defense. The overall results suggest that GnIH gene silencing induces arousal. In addition, the activities of male and female birds were negatively correlated with GnIH mRNA expression in the paraventricular nucleus. Density of GnIH neuronal fibers in the ventral tegmental area was decreased by GnIH RNAi treatment in female birds, and the number of gonadotropin-releasing hormone neurons that received close appositions of GnIH neuronal fiber terminals was negatively correlated with the activity of male birds. In summary, GnIH may decrease arousal level resulting in the inhibition of specific motivated behavior such as in reproductive contexts

The networked micro-decision context: A new lens on transformative urban governance

Recent large-scale societal disruptions, from the COVID-19 pandemic to intensifying wildfires and weather events, reveal the importance of transforming governance systems so they can address complex, transboundary, and rapidly evolving crises. Yet current knowledge of the decision-making dynamics that yield transformative governance remains scant. Studies typically focus on the aggregate outputs of government decisions, while overlooking their micro-level underpinnings. This is a key oversight because drivers of policy change, such as learning or competition, are prosecuted by people rather than organizations. We respond to this knowledge gap by introducing a new analytical lens for understanding policymaking, aimed at uncovering how characteristics of decision-makers and the structure of their relationships affect their likelihood of effectuating transformative policy responses. This perspective emphasizes the need for a more dynamic and relational view on urban governance in the context of transformation