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Draft Genome Sequence of Bacillus velezensis CE2, Which Genetically Encodes a Novel Multicomponent Lantibiotic.
Bacillus velezensis CE2 produces potent antimicrobial compound(s). The draft genome sequence of the strain reported here is 4.1 Mb with a G+C content of 46.1%. Whole-genome sequencing revealed that the strain genetically encodes a novel multicomponent lantibiotic, velezensicidin
An experimental and theoretical guide to strongly interacting Rydberg gases
We review experimental and theoretical tools to excite, study and understand
strongly interacting Rydberg gases. The focus lies on the excitation of dense
ultracold atomic samples close to, or within quantum degeneracy, to high lying
Rydberg states. The major part is dedicated to highly excited S-states of
Rubidium, which feature an isotropic van-der-Waals potential. Nevertheless, the
setup and the methods presented are also applicable to other atomic species
used in the field of laser cooling and atom trapping.Comment: 23 pages, 22 figures, tutoria
Genetic Mechanisms Underlying the Pathogenicity of Cold-Stressed Salmonella Enterica Serovar Typhimurium in Cultured Intestinal Epithelial Cells
Salmonella encounters various stresses in the environment and in the host during infection. The effects of cold (5 C, 48 h), peroxide (5 mM H2O2, 5 h) and acid stress (pH 4.0, 90 min) were tested on pathogenicity of Salmonella. Prior exposure of Salmonella to cold stress significantly (P \u3c 0.05) increased adhesion and invasion of cultured intestinal epithelial (Caco-2) cells. This increased Salmonella-host cell association was also correlated with significant induction of several virulence-associated genes, implying an increased potential of cold-stressed Salmonella to cause an infection. In Caco-2 cells infected with cold-stressed Salmonella, genes involved in the electron transfer chain were significantly induced, but no simultaneous significant increase in expression of antioxidant genes that neutralize the effect of superoxide radicals or reactive oxygen species was observed. Increased production of caspase 9 and caspase 3/7 was confirmed during host cell infection with cold-stressed Salmonella. Further, a prophage gene, STM2699, induced in cold-stressed Salmonella and a spectrin gene, SPTAN1, induced in Salmonella-infected intestinal epithelial cells were found to have a significant contribution in increased adhesion and invasion of cold-stressed Salmonella in epithelial cells
Quantitative maps of geomagnetic perturbation vectors during substorm onset and recovery
We have produced the first series of spherical harmonic, numerical maps of the time‐dependent surface perturbations in the Earth's magnetic field following the onset of substorms. Data from 124 ground magnetometer stations in the Northern Hemisphere at geomagnetic latitudes above 33° were used. Ground station data averaged over 5 min intervals covering 8 years (1998–2005) were used to construct pseudo auroral upper, auroral lower, and auroral electrojet (AU*, AL*, and AE*) indices. These indices were used to generate a list of substorms that extended from 1998 to 2005, through a combination of automated processing and visual checks. Events were sorted by interplanetary magnetic field (IMF) orientation (at the Advanced Composition Explorer (ACE) satellite), dipole tilt angle, and substorm magnitude. Within each category, the events were aligned on substorm onset. A spherical cap harmonic analysis was used to obtain a least error fit of the substorm disturbance patterns at 5 min intervals up to 90 min after onset. The fits obtained at onset time were subtracted from all subsequent fits, for each group of substorm events. Maps of the three vector components of the averaged magnetic perturbations were constructed to show the effects of substorm currents. These maps are produced for several specific ranges of values for the peak |AL*| index, IMF orientation, and dipole tilt angle. We demonstrate an influence of the dipole tilt angle on the response to substorms. Our results indicate that there are downward currents poleward and upward currents just equatorward of the peak in the substorms' westward electrojet.Key PointsShow quantitative maps of ground geomagnetic perturbations due to substormsThree vector components mapped as function of time during onset and recoveryCompare/contrast results for different tilt angle and sign of IMF Y‐componentPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110891/1/jgra51610.pd
RePulmo: A Remote Pulmonary Monitoring System
Remote physiological monitoring is increasing in popularity with the evolution of technologies in the healthcare industry. However, the current solutions for remote monitoring of blood-oxygen saturation, one of the most common continuously monitored vital signs, either have inconsistent accuracy or are not secure for transmitting over the network. In this paper, we propose RePulmo, an open-source platform for secure and accurate remote pulmonary data monitoring. RePulmo satisfies both robustness and security requirements by utilizing hospital-grade pulse oximeter devices with multiple layers of security enforcement. We describe two applications of RePulmo, namely (1) a remote pulmonary monitoring system for infants to support the Children’s Hospital of Philadelphia (CHOP) clinical trial; (2) a proof-of-concept of a low SpO2 smart alarm system
Neural Attentive Session-based Recommendation
Given e-commerce scenarios that user profiles are invisible, session-based
recommendation is proposed to generate recommendation results from short
sessions. Previous work only considers the user's sequential behavior in the
current session, whereas the user's main purpose in the current session is not
emphasized. In this paper, we propose a novel neural networks framework, i.e.,
Neural Attentive Recommendation Machine (NARM), to tackle this problem.
Specifically, we explore a hybrid encoder with an attention mechanism to model
the user's sequential behavior and capture the user's main purpose in the
current session, which are combined as a unified session representation later.
We then compute the recommendation scores for each candidate item with a
bi-linear matching scheme based on this unified session representation. We
train NARM by jointly learning the item and session representations as well as
their matchings. We carried out extensive experiments on two benchmark
datasets. Our experimental results show that NARM outperforms state-of-the-art
baselines on both datasets. Furthermore, we also find that NARM achieves a
significant improvement on long sessions, which demonstrates its advantages in
modeling the user's sequential behavior and main purpose simultaneously.Comment: Proceedings of the 2017 ACM on Conference on Information and
Knowledge Management. arXiv admin note: text overlap with arXiv:1511.06939,
arXiv:1606.08117 by other author
Heat flux operator, current conservation and the formal Fourier's law
By revisiting previous definitions of the heat current operator, we show that
one can define a heat current operator that satisfies the continuity equation
for a general Hamiltonian in one dimension. This expression is useful for
studying electronic, phononic and photonic energy flow in linear systems and in
hybrid structures. The definition allows us to deduce the necessary conditions
that result in current conservation for general-statistics systems. The
discrete form of the Fourier's Law of heat conduction naturally emerges in the
present definition
In vitro gas production as a surrogate measure of the fermentability of cellulosic biomass to ethanol
Current methods for measuring ethanol yields from lignocellulosic biomass are relatively slow and are not well geared for analyzing large numbers of samples generated by feedstock management and breeding research. The objective of this study was to determine if an in vitro ruminal fermentation assay used in forage quality research was predictive of results obtained using a conventional biomass-to-ethanol conversion assay. In the conventional assay, herbaceous biomass samples were converted to ethanol by Saccharomyces cerevisiae cultures in the presence of cellulase enzymes. Cultures were grown in sealed serum bottles and gas production monitored by measuring increasing head space pressure. Gas accumulation as calculated from the pressure measurements was highly correlated (r2\u3e0.9) with ethanol production measured by gas chromatography at 24 h or 7 days. The same
feedstocks were also analyzed by in vitro ruminal digestion, as also measured by gas accumulation. Good correlations (r2∼0.63–0.82) were observed between ethanol production during simultaneous saccharification and fermentation and gas accumulation in parallel in vitro ruminal fermentations. Because the in vitro ruminal fermentation assay can be performed without sterilization of the medium and does not require aseptic conditions, this assay may be useful for biomass feedstock agronomic and breeding research
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