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The deep terrestrial biosphere harbours a substantial fraction of Earth's biomass and remains understudied compared with other ecosystems. Deep biosphere life primarily consists of bacteria and archaea, yet knowledge of their co-occurring viruses is poor. Here, we temporally catalogued viral diversity from five deep terrestrial subsurface locations (hydraulically fractured wells), examined virus-host interaction dynamics and experimentally assessed metabolites from cell lysis to better understand viral roles in this ecosystem. We uncovered high viral diversity, rivalling that of peatland soil ecosystems, despite low host diversity. Many viral operational taxonomic units were predicted to infect Halanaerobium, the dominant microorganism in these ecosystems. Examination of clustered regularly interspaced short palindromic repeats-CRISPR-associated proteins (CRISPR-Cas) spacers elucidated lineage-specific virus-host dynamics suggesting active in situ viral predation of Halanaerobium. These dynamics indicate repeated viral encounters and changing viral host range across temporally and geographically distinct shale formations. Laboratory experiments showed that prophage-induced Halanaerobium lysis releases intracellular metabolites that can sustain key fermentative metabolisms, supporting the persistence of microorganisms in this ecosystem. Together, these findings suggest that diverse and active viral populations play critical roles in driving strain-level microbial community development and resource turnover within this deep terrestrial subsurface ecosystem.

The Gold King Mine spill in August 2015 released 11 million liters of metal-rich mine waste to the Animas River watershed, an area that has been previously exposed to historical mining activity spanning more than a century. Although adsorption onto fluvial sediments was responsible for rapid immobilization of a significant fraction of the spill-associated metals, patterns of longer-term mobility are poorly constrained. Metals associated with river sediments collected downstream of the Gold King Mine in August 2015 exhibited distinct presence and abundance patterns linked to location and mineralogy. Simulating riverbed burial and development of anoxic conditions, sediment microcosm experiments amended with Animas River dissolved organic carbon revealed the release of specific metal pools coupled to microbial Fe- and SO42--reduction. Results suggest that future sedimentation and burial of riverbed materials may drive longer-term changes in patterns of metal remobilization linked to anaerobic microbial metabolism, potentially driving decreases in downstream water quality. Such patterns emphasize the need for long-term water monitoring efforts in metal-impacted watersheds.

The microwave spectrum (6500-18 500 MHz) of 1-fluoro-1-silacyclopentane, c-C4H8SiHF has been recorded and 87 transitions for the 28Si, 29Si, 30Si, and 13C isotopomers have been assigned for a single conformer. Infrared spectra (3050-350 cm-1) of the gas and solid and Raman spectrum (3100-40 cm-1) of the liquid have also been recorded. The vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twist form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers to be saddle points with nearly the same energies but much lower energy than the planar conformer. By utilizing the microwave rotational constants for seven isotopomers (28Si, 29Si, 30Si, and four 13C) combined with the structural parameters predicted from the MP2(full)/6-311+G(d,p) calculations, adjusted r0 structural parameters have been obtained for the twist conformer. The heavy atom distances in Å are: r0(SiC2) = 1.875(3); r0(SiC3) = 1.872(3); r0(C2C4) = 1.549(3); r0(C3C5) = 1.547(3); r0(C4C5) = 1.542(3); r0(SiF) = 1.598(3) and the angles in degrees are: ∠CSiC = 96.7(5); ∠SiC2C4 = 103.6(5); ∠SiC3C5 = 102.9(5); ∠C2C4C5 = 108.4(5); ∠C3C5C4 = 108.1(5); ∠F6Si1C2 = 110.7(5); ∠F6Si1C3 = 111.6(5). The heavy atom ring parameters are compared to the corresponding rs parameters. Normal coordinate calculations with scaled force constants from MP2(full)/6-31G(d) calculations were carried out to predict the fundamental vibrational frequencies, infrared intensities, Raman activities, depolarization values, and infrared band contours. These experimental and theoretical results are compared to the corresponding quantities of some other five-membered rings. [ABSTRACT FROM AUTHOR]

During extended exploration trips in caves, it is sometimes not possible to remove all excreted urine due to its volume and weight. Excess urine can be particularly problematic in dry caves where, without dilution, urine introduces a significant source of nitrogen into these otherwise nitrogen-limited environments. It was the aim of this study to determine the impact that human urine could have on cave microbiota over an extended period of time. To do this, we examined the microbial community structure of a heavily impacted site in Lechuguilla Cave, USA. Using a molecular phylogenetic approach we generated a 136-member 16S rRNA clone library that demonstrated representatives of the Alpha- Beta- and Gammaproteobacteria, the Bacteroidetes, Firmicutes, Actinobacteria and Deinococcus-Thermus group at this site. The structure of the microbial community at the impacted site suggests that it is colonized by endemic cave species rather than human commensal organisms, while metabolic inference suggests that these organisms are taking advantage of both the nitrogenous and organic compounds in urine for growth. The intrinsic nature of such metabolic activity in the cave environment was confirmed by examining non-impacted sites using cultivation, which demonstrated that endemic species express both the capacity to degrade urine and to reduce urea to nitrogen gas. Our results differ from those of previous studies by implying a more resilient nature of the microbial ecosystem in caves to invasion by exogenous (commensal) species, while suggesting that endemic microbial species may be able to mitigate the impact of excess nitrogen in the cave through bioremediation. [ABSTRACT FROM AUTHOR]

The article focuses on the higher level of litigation explosion which consumes the productivity, profits and general effectiveness of industries in the U.S. It explores the reforms proposed by lawmakers and business leaders to reduce litigation and summarizes the evidences which establish the existence of litigation explosion. It evaluates the proposal of stricter limitations on the methods of litigation and reviews allegations that frivolous lawsuits impose burden on the legal system.

The goals of the resent study are (a) to asses the construct validity of the Comprehensive Level of Consciousness Scale (CLOCS), (b) to examine the contribution of behavioral measures to prediction of outcome following severe insult to the central nervous system, and (c) to determine the unique proportions of outcome variance explained by neurodiagnostic and behavioral measures. The results provide support for the construct validity of the CLOCS. In addition, the data indicate that behavioral measures do indeed possess significant prognostic value above and beyond that of neurodiagnostic measures alone. Finally, a decomposition of outcome variance demonstrates that behavioral measures explain a unique proportion of outcome variance which is roughly comparable to that explained by neurodiagnostic procedures. These results are discussed in terms of their clinical and research implications. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Ultrafiltration (UF) is used to treat patients with diuretic-resistant acute decompensated eart failure. The aim of this study was to identify predictors and the effect of worsening renal failure(WRF) on mortality in patients treated with UF. METHODS AND RESULTS: Based on changes in serum creatinine, 99 patients treated with UF were divided into WRF and control groups. Overall creatinine increased from 1.9 6 0.7 to 1.2 6 1.0 mg/dL (P!.001),and WRF developed in 41% of the subjects. The peak UF rate was higher in the WRF group in univariate analysis (174 6 75 vs 144 6 52 mL/h; P 5 .03). Based on multivariate analysis, aldosterone antagonist treatment (odds ratio [OR] 3.38, 95% confidence interval [CI] 1.17e13.46, P 5 .04), heart rate #65 beats/min (OR 6.03, 95% CI 1.48e48.42; P 5 .03), and E/E0 $15 (OR 3.78, 95% CI 1.26e17.55; P 5 .04) at hospital admission were associated with WRF. Patients with baseline glomerular filtration rate (GFR) #60mg/dL who developed WRF during UF had a 75% 1-year mortality rate. CONCLUSIONS: WRF occurred frequently during UF. Increased LV filling pressures, lower heart rate, and treatment with aldosterone antagonist at hospital admission can identify patients at increased risk for WRF. Patients with baseline GFR #60 mg/dL and WRF during UF have an extremely high 1-year mortality rate. [ABSTRACT FROM AUTHOR]