Chromatin proteins and RNA are associated with DNA during all phases of mitosis.

Mitosis brings about major changes to chromosome and nuclear structure. We used recently developed proximity ligation assay-based techniques to investigate the association with DNA of chromatin-associated proteins and RNAs in Drosophila embryos during mitosis. All groups of tested proteins, histone-modifying and chromatin-remodeling proteins and methylated histones remained in close proximity to DNA during all phases of mitosis. We also found that RNA transcripts are associated with DNA during all stages of mitosis. Reduction of H3K27me3 levels or elimination of RNAs had no effect on the association of the components of PcG and TrxG complexes to DNA. Using a combination of proximity ligation assay-based techniques and super-resolution microscopy, we found that the number of protein-DNA and RNA-DNA foci undergoes significant reduction during mitosis, suggesting that mitosis may be accompanied by structural re-arrangement or compaction of specific chromatin domains

Cooperative Carbon Dioxide Adsorption in Alcoholamine- and Alkoxyalkylamine-Functionalized Metal-Organic Frameworks.

A series of structurally diverse alcoholamine- and alkoxyalkylamine-functionalized variants of the metal-organic framework Mg2 (dobpdc) are shown to adsorb CO2 selectively via cooperative chain-forming mechanisms. Solid-state NMR spectra and optimized structures obtained from van der Waals-corrected density functional theory calculations indicate that the adsorption profiles can be attributed to the formation of carbamic acid or ammonium carbamate chains that are stabilized by hydrogen bonding interactions within the framework pores. These findings significantly expand the scope of chemical functionalities that can be utilized to design cooperative CO2 adsorbents, providing further means of optimizing these powerful materials for energy-efficient CO2 separations

Multihospital System Affiliation as a Survival Strategy for Rural Hospitals Under the Prospective Payment System

The introduction of Medicare's Prospective Payment System (PPS) has disproportionately increased financial pressures on rural hospitals and posed challenges to the survival of these institutions. Increasingly, rural hospitals are seeking strategies that can enhance their chances for survival in a turbulent and hostile environment. This study examined the survival effects of one such strategy, multihospital system affiliation. Specifically, we assessed: (1) whether and how different types of system affiliation in the post-PPS era affect the likelihood of rural hospital survival; (2) whether particular structural, environmental and hospital performance characteristics moderate the effects of system affiliation on rural hospital survival; and (3) whether systematic selection by rural hospitals into multihospital systems potentially accounts for observed relationships between system affiliation and survival. Proportional hazards analyses indicate that system affiliation with investor-owned systems significantly reduces survival probabilities of rural hospitals. Affiliation with not-for-profit systems or system affiliation under contract management arrangements does not affect survival probabilities of rural hospitals. These general findings are moderated by the effects of hospital ownership and size at the time of affiliation. Finally, study findings indicated that systematic selection by poor performing rural hospitals into investor-owned systems has occurred in the post-PPS era. No evidence of selection into not-for-profit systems was discovered.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73618/1/j.1748-0361.1992.tb00334.x.pd

Structure of the RNA-dependent RNA polymerase of poliovirus

AbstractBackground: The central player in the replication of RNA viruses is the viral RNA-dependent RNA polymerase. The 53 kDa poliovirus polymerase, together with other viral and possibly host proteins, carries out viral RNA replication in the host cell cytoplasm. RNA-dependent RNA polymerases comprise a distinct category of polymerases that have limited sequence similarity to reverse transcriptases (RNA-dependent DNA polymerases) and perhaps also to DNA-dependent polymerases. Previously reported structures of RNA-dependent DNA polymerases, DNA-dependent DNA polymerases and a DNA-dependent RNA polymerase show that structural and evolutionary relationships exist between the different polymerase categories.Results: We have determined the structure of the RNA-dependent RNA polymerase of poliovirus at 2.6 Å resolution by X-ray crystallography. It has the same overall shape as other polymerases, commonly described by analogy to a right hand. The structures of the ‘fingers’ and ‘thumb’ subdomains of poliovirus polymerase differ from those of other polymerases, but the palm subdomain contains a core structure very similar to that of other polymerases. This conserved core structure is composed of four of the amino acid sequence motifs described for RNA-dependent polymerases. Structure-based alignments of these motifs has enabled us to modify and extend previous sequence and structural alignments so as to relate sequence conservation to function. Extensive regions of polymerase–polymerase interactions observed in the crystals suggest an unusual higher order structure that we believe is important for polymerase function.Conclusions: As a first example of a structure of an RNA-dependent RNA polymerase, the poliovirus polymerase structure provides for a better understanding of polymerase structure, function and evolution. In addition, it has yielded insights into an unusual higher order structure that may be critical for poliovirus polymerase function

Hydrometeorology and flood pulse dynamics drive diarrheal disease outbreaks and increase vulnerability to climate change in surface-water-dependent populations: A retrospective analysis

Background The impacts of climate change on surface water, waterborne disease, and human health remain a growing area of concern, particularly in Africa, where diarrheal disease is one of the most important health threats to children under 5 years of age. Little is known about the role of surface water and annual flood dynamics (flood pulse) on waterborne disease and human health nor about the expected impact of climate change on surface-water-dependent populations. Methods and findings Using the Chobe River in northern Botswana, a flood pulse river—floodplain system, we applied multimodel inference approaches assessing the influence of river height, water quality (bimonthly counts of Escherichia coli and total suspended solids [TSS], 2011–2017), and meteorological variability on weekly diarrheal case reports among children under 5 presenting to health facilities (n = 10 health facilities, January 2007–June 2017). We assessed diarrheal cases by clinical characteristics and season across age groups using monthly outpatient data (January 1998–June 2017). A strong seasonal pattern was identified, with 2 outbreaks occurring regularly in the wet and dry seasons. The timing of outbreaks diverged from that at the level of the country, where surface water is largely absent. Across age groups, the number of diarrheal cases was greater, on average, during the dry season. Demographic and clinical characteristics varied by season, underscoring the importance of environmental drivers. In the wet season, rainfall (8-week lag) had a significant influence on under-5 diarrhea, with a 10-mm increase in rainfall associated with an estimated 6.5% rise in the number of cases. Rainfall, minimum temperature, and river height were predictive of E. coli concentration, and increases in E. coli in the river were positively associated with diarrheal cases. In the dry season, river height (1-week lag) and maximum temperature (1- and 4-week lag) were significantly associated with diarrheal cases. During this period, a 1-meter drop in river height corresponded to an estimated 16.7% and 16.1% increase in reported diarrhea with a 1- and 4-week lag, respectively. In this region, as floodwaters receded from the surrounding floodplains, TSS levels increased and were positively associated with diarrheal cases (0- and 3-week lag). Populations living in this region utilized improved water sources, suggesting that hydrological variability and rapid water quality shifts in surface waters may compromise water treatment processes. Limitations include the potential influence of health beliefs and health seeking behaviors on data obtained through passive surveillance. Conclusions In flood pulse river—floodplain systems, hydrology and water quality dynamics can be highly variable, potentially impacting conventional water treatment facilities and the production of safe drinking water. In Southern Africa, climate change is predicted to intensify hydrological variability and the frequency of extreme weather events, amplifying the public health threat of waterborne disease in surface-water-dependent populations. Water sector development should be prioritized with urgency, incorporating technologies that are robust to local environmental conditions and expected climate-driven impacts. In populations with high HIV burdens, expansion of diarrheal disease surveillance and intervention strategies may also be needed. As annual flood pulse processes are predominantly influenced by climate controls in distant regions, country-level data may be inadequate to refine predictions of climate—health interactions in these systems

Semi-Supervised First-Person Activity Recognition in Body-Worn Video

Body-worn cameras are now commonly used for logging daily life, sports, and law enforcement activities, creating a large volume of archived footage. This paper studies the problem of classifying frames of footage according to the activity of the camera-wearer with an emphasis on application to real-world police body-worn video. Real-world datasets pose a different set of challenges from existing egocentric vision datasets: the amount of footage of different activities is unbalanced, the data contains personally identifiable information, and in practice it is difficult to provide substantial training footage for a supervised approach. We address these challenges by extracting features based exclusively on motion information then segmenting the video footage using a semi-supervised classification algorithm. On publicly available datasets, our method achieves results comparable to, if not better than, supervised and/or deep learning methods using a fraction of the training data. It also shows promising results on real-world police body-worn video

The Properties of the local Interstellar Medium and the Interaction of the Stellar Winds of epsilon Indi and lambda Andromedae with the Interstellar Environment

We present new observations of the Ly alpha lines of Epsilon Indi (K5 5) and A Andromedae (G8 4-3 + ?) These data were obtained by the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope. Analysis of the interstellar H 1 and D 1 absorption lines reveals that the velocities and temperatures inferred from the H 1 lines are inconsistent with the parameters inferred from the D 1 lines, unless the H 1 absorption is assumed to be produced by two absorption components. One absorption component is produced by interstellar material. For both lines of sight observed, the velocity of this component is consistent with the velocity predicted by the local flow vector. For the Epsilon Indi data, the large velocity separation between the stellar emission and the interstellar absorption allows us to measure the H 1 column density independent of the shape of the intrinsic stellar Ly alpha profile. This approach permits us to quote an accurate column density and to assess its uncertainty with far more confidence than in previous analyses, for which the errors were dominated by uncertainties in the assumed stellar profiles