The NEOWISE-Discovered Comet Population and the CO+CO_2 production rates

The 163 comets observed during the WISE/NEOWISE prime mission represent the largest infrared survey to date of comets, providing constraints on dust, nucleus size, and CO + CO_2 production. We present detailed analyses of the WISE/NEOWISE comet discoveries, and discuss observations of the active comets showing 4.6 μm band excess. We find a possible relation between dust and CO + CO_2 production, as well as possible differences in the sizes of long and short period comet nuclei

Centaurs and Scattered Disk Objects in the Thermal Infrared: Analysis of WISE/NEOWISE Observations

The Wide-field Infrared Survey Explorer (WISE) observed 52 Centaurs and scattered disk objects (SDOs) in the thermal infrared, including 15 new discoveries. We present analyses of these observations to estimate sizes and mean optical albedos. We find mean albedos of 0.08 ± 0.04 for the entire data set. Thermal fits yield average beaming parameters of 0.9 ± 0.2 that are similar for both SDO and Centaur sub-classes. Biased cumulative size distributions yield size-frequency distribution power law indices of ~–1.7 ± 0.3. The data also reveal a relation between albedo and color at the 3σ level. No significant relation between diameter and albedos is found

Whole-genome sequencing and annotation of Bacillus safensis RIT372 and Pseudomonas oryzihabitans RIT370 from Capsicum annuum (bird\u27s eye chili) and Capsicum chinense (yellow lantern chili), respectively

Here, we report the genome sequences of Bacillus safensis RIT372 and Pseudomonas oryzihabitans RIT370 from Capsicum spp. Annotation revealed gene clusters for the synthesis of bacilysin, lichensin, and bacillibactin and sporulation killing factor (skfA) in Bacillus safensis RIT372 and turnerbactin and carotenoid in Pseudomonas oryzihabitans RIT370

Genome sequencing-assisted identification and the first functional validation of N-acyl-homoserine-lactone synthases from the Sphingomonadaceae family

Background Members of the genus Novosphingobium have been isolated from a variety of environmental niches. Although genomics analyses have suggested the presence of genes associated with quorum sensing signal production e.g., the N-acyl-homoserine lactone (AHL) synthase (luxI) homologs in various Novosphingobium species, to date, no luxI homologs have been experimentally validated. Methods In this study, we report the draft genome of the N-(AHL)-producing bacterium Novosphingobium subterraneum DSM 12447 and validate the functions of predicted luxI homologs from the bacterium through inducible heterologous expression in Agrobacterium tumefaciens strain NTL4. We developed a two-dimensional thin layer chromatography bioassay and used LC-ESI MS/MS analyses to separate, detect and identify the AHL signals produced by the N. subterraneum DSM 12447 strain. Results Three predicted luxI homologs were annotated to the locus tags NJ75_2841 (NovINsub1), NJ75_2498 (NovINsub2), and NJ75_4146 (NovINsub3). Inducible heterologous expression of each luxI homologs followed by LC-ESI MS/MS and two-dimensional reverse phase thin layer chromatography bioassays followed by bioluminescent ccd camera imaging indicate that the three LuxI homologs are able to produce a variety of medium-length AHL compounds. New insights into the LuxI phylogeny was also gleemed as inferred by Bayesian inference. Discussion This study significantly adds to our current understanding of quorum sensing in the genus Novosphingobium and provide the framework for future characterization of the phylogenetically interesting LuxI homologs from members of the genus Novosphingobium and more generally the family Sphingomonadaceae

Functional connectivity of the default mode network predicts subsequent polysomnographically measured sleep in people with symptoms of insomnia

Insomnia is often accompanied by excessive pre-sleep rumination. Such ruminative thinking is also associated with increased connectivity of the default mode network (DMN). It is likely that DMN connectivity and associated rumination contribute to the pathogenesis of insomnia. We hypothesized that resting state functional connectivity (rsFC) between the DMN and other brain regions prior to bedtime would predict objectively measured sleep among individuals with insomnia. Twenty participants (12 female; M age = 26.9, SD = 6.6 years) with symptoms of insomnia underwent an rsFC scan in the early evening followed by a night of polysomographically (PSG) measured sleep. Connectivity of the DMN with other brain regions was regressed against several PSG sleep metrics, including time in wake, N1, N2, N3, REM, total sleep time (TST), and sleep efficiency (SE) at a cluster corrected false discovery rate (FDR) correction P < 0.05. The connectivity between DMN and cortical regions was negatively correlated with PSG indices of poorer sleep including time in wake (right angular gyrus) and N1 (precuneus) but positively correlated with time in REM (orbitofrontal cortex), TST (insula, orbitofrontal cortex, superior frontal gyrus, paracingulate gyrus), SE (orbitofrontal cortex). Connectivity between DMN and the pons was negatively correlated with SE. Among individuals with symptoms of insomnia, better sleep was predicted by rsFC between the DMN and cortical regions involved in executive functioning, consciousness, and complex cognition. Findings raise the possibility that future interventions aimed at suppressing pre-sleep DMN activation may weaken synergy between pre-sleep ruminative worry and complex cognitions, potentially ameliorating problems falling asleep. Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.Open access articleThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Chemical Composition and Disruption of Quorum Sensing Signaling in Geographically Diverse United States Propolis

Propolis or bee glue has been used for centuries for various purposes and is especially important in human health due to many of its biological and pharmacological properties. In this work we showed quorum sensing inhibitory (QSI) activity of ten geographically distinct propolis samples from the United States using the acyl-homoserine lactone- (AHL-) dependent Chromobacterium violaceum strain CV026. Based on GC-MS chemical profiling the propolis samples can be classified into several groups that are as follows: (1) rich in cinnamic acid derivatives, (2) rich in flavonoids, and (3) rich in triterpenes. An in-depth analysis of the propolis from North Carolina led to the isolation and identification of a triterpenic acid that was recently isolated from Hondurian propolis (Central America) and ethyl ether of p-coumaric alcohol not previously identified in bee propolis. QSI activity was also observed in the second group US propolis samples which contained the flavonoid pinocembrin in addition to other flavonoid compounds. The discovery of compounds that are involved in QSI activity has the potential to facilitate studies that may lead to the development of antivirulence therapies that can be complementary and/or alternative treatments against antibiotic resistant bacterial pathogens and/or emerging pathogens that have yet to be identified