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\"Perplexed by plate tectonics? Confused by climates? Disorientated by demographics? Help Your Kids With Geography helps parents to get a grasp on what their children learn in geography class by exploring all these topics and more.\"--Publisher's description.

Cell surface signaling (CSS) is a means of rapidly adjusting transcription in response to extracellular stimuli in Gram-negative bacteria. The pseudobactin BN7/8 uptake (Pup) system not only imports iron but also upregulates its own transcription through CSS in Pseudomonas capeferrum. In the absence of ferric pseudobactin BN7/8, the signaling components are maintained in a resting state via the formation of a periplasmic complex between the N-terminal signaling domain (NTSD) of the outer membrane iron-transporter, PupB, and the C-terminal CSS domain (CCSSD) of the sigma regulator, PupR. The previously determined 1.6 Å crystal structure of this periplasmic complex has allowed us to probe the structural and thermodynamic consequences of mutating key interfacial residues. In this report, we describe the solution structure of the PupB NTSD and use Nuclear Magnetic Resonance spectroscopy, Isothermal Titration Calorimetry, and Circular Dichroism spectroscopy together with thermal denaturation to investigate whether three PupB point mutations, Q69K, H72D, and L74A, influence the interaction merely due to the chemical nature of the amino acid substitution or also cause changes in overall protein structure. Our results demonstrate that binding to the PupR CCSSD does not alter the structure of PupB NTSD and that the individual mutations have only minor effects on structure. The mutations generally lower thermodynamic stability of the NTSD and weaken binding to the CCSSD. These findings validate the X-ray crystal structure interface, emphasizing the importance of amino acid chemical nature at the interface.

The Illinois River Watershed is a multi-facet basin with ecological and economic importance to its local stakeholders in northwest Arkansas and northeast Oklahoma, USA. The numbers, transport and sources of fecal bacteria in streams was identified as a research priority of the USDA NRI Water and Watershed Program in 2006, and the objective of this study was to evaluate the relation between fecal bacteria and other measured physicochemical parameters in water samples collected from selected sites throughout the Illinois River Watershed. An existing database (i.e., National Water Information Systems, NWIS) from the US Geological Survey (USGS) was used in this project. The data obtained includes discharge, pH, temperature, dissolved oxygen, Escherichia coli (E. coli), fecal coliform, and fecal streptococci among several other physic-chemical parameters. A synthetic model, based on multi-regression analysis, was developed to predict fecal bacteria numbers at these selected sites based on available USGS NWIS data, and the multiple regressions were significant at almost every site for all three bacteria groups. However, the physicochemical parameters used in the equations were very different across sites and fecal bacteria groups, suggesting that the development of such predictive models is site and bacteria group specific even within one watershed.

Hydraulic fracturing is one of the industrial processes behind the surging natural gas output in the United States. This technology inadvertently creates an engineered microbial ecosystem thousands of meters below Earth’s surface. Here, we used laboratory reactors to perform manipulations of persisting shale microbial communities that are currently not feasible in field scenarios. Metaproteomic and metabolite findings from the laboratory were then corroborated using regression-based modeling performed on metagenomic and metabolite data from more than 40 produced fluids from five hydraulically fractured shale wells. Collectively, our findings show that Halanaerobium, Geotoga, and Methanohalophilus strain abundances predict a significant fraction of nitrogen and carbon metabolites in the field. Our laboratory findings also exposed cryptic predatory, cooperative, and competitive interactions that impact microorganisms across fractured shales. Scaling these results from the laboratory to the field identified mechanisms underpinning biogeochemical reactions, yielding knowledge that can be harnessed to potentially increase energy yields and inform management practices in hydraulically fractured shales.

A panel of veterinary and academic experts reviewed current available evidence on age at death for labradors and reached a consensus that their average/typical life span was 12years of age.1 A prospective cohort study that described the longevity of 39 pedigree adult neutered labradors, showed that 89.7 per cent lived to meet/exceed this typical life span. The study showed that maintenance of lean body mass and reduced accumulation of body fat were associated with attaining a longer than average life span while sex and age at neutering were not associated with longevity.

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. Metagenomes from hydraulically fractured wells over time identified viral operational taxonomic units predicted to actively infect dominant bacteria, and in vitro experiments show that viral lysis of these hosts can release metabolites important for fermentation.

The polyamines spermine, spermidine, and putrescine are small organic molecules one or more of which are present in all living organisms. Many natural products contain polyamine residues. Polyamines are synthesized by a highly regulated pathway from arginine or ornithine and also can be transported in and out of cells. Polyamines are degraded to a variety of compounds the functions of which are largely unknown. Polyamines influence the transcriptional and translational stages of protein synthesis, stabilize membranes, and, in mammalian systems, modulate neurophysiological functions and may act as intracellular messengers. However, at the molecular level the mode of action of the polyamines is largely unknown.

Since the introduction of breast-conserving treatment, various radiation doses after lumpectomy have been used. In a phase 3 randomised controlled trial, we investigated the effect of a radiation boost of 16 Gy on overall survival, local control, and fibrosis for patients with stage I and II breast cancer who underwent breast-conserving treatment compared with patients who received no boost. Here, we present the 20-year follow-up results. Patients with microscopically complete excision for invasive disease followed by whole-breast irradiation of 50 Gy in 5 weeks were centrally randomised (1:1) with a minimisation algorithm to receive 16 Gy boost or no boost, with minimisation for age, menopausal status, presence of extensive ductal carcinoma in situ, clinical tumour size, nodal status, and institution. Neither patients nor investigators were masked to treatment allocation. The primary endpoint was overall survival in the intention-to-treat population. The trial is registered with ClinicalTrials.gov, number NCT02295033. Between May 24, 1989, and June 25, 1996, 2657 patients were randomly assigned to receive no radiation boost and 2661 patients randomly assigned to receive a radiation boost. Median follow-up was 17·2 years (IQR 13·0–19·0). 20-year overall survival was 59·7% (99% CI 56·3–63·0) in the boost group versus 61·1% (57·6–64·3) in the no boost group, hazard ratio (HR) 1·05 (99% CI 0·92–1·19, p=0·323). Ipsilateral breast tumour recurrence was the first treatment failure for 354 patients (13%) in the no boost group versus 237 patients (9%) in the boost group, HR 0·65 (99% CI 0·52–0·81, p<0·0001). The 20-year cumulative incidence of ipsilatelal breast tumour recurrence was 16·4% (99% CI 14·1–18·8) in the no boost group versus 12·0% (9·8–14·4) in the boost group. Mastectomies as first salvage treatment for ipsilateral breast tumour recurrence occurred in 279 (79%) of 354 patients in the no boost group versus 178 (75%) of 237 in the boost group. The cumulative incidence of severe fibrosis at 20 years was 1·8% (99% CI 1·1–2·5) in the no boost group versus 5·2% (99% CI 3·9–6·4) in the boost group (p<0·0001). A radiation boost after whole-breast irradiation has no effect on long-term overall survival, but can improve local control, with the largest absolute benefit in young patients, although it increases the risk of moderate to severe fibrosis. The extra radiation dose can be avoided in most patients older than age 60 years. Fonds Cancer, Belgium.

A panel of veterinary and academic experts reviewed current available evidence on age at death for Labrador and reached a consensus that their average/typical lifespan was 12 years of age (Adams and others, 2016). A prospective cohort study that described the longevity of 39 pedigree adult neutered Labradors, showed that 89.7% lived to meet/exceed this typical lifespan. The study showed that maintenance of lean body mass and reduced accumulation of body fat were associated with attaining a longer than average lifespan whilst gender and age at neutering were not associated with longevity (Adams and others 2016).

Hydraulic fracturing is one of the industrial processes behind the surging natural gas output in the United States. This technology inadvertently creates an engineered microbial ecosystem thousands of meters below Earth’s surface. Here, we used laboratory reactors to perform manipulations of persisting shale microbial communities that are currently not feasible in field scenarios. Metaproteomic and metabolite findings from the laboratory were then corroborated using regression based modeling performed on metagenomic and metabolite data from more than 40 produced fluids from five hydraulically fractured shale wells. Collectively, our findings show that Halanaerobium, Geotoga, and Methanohalophilius strain abundances predict a significant fraction of nitrogen and carbon metabolites in the field. Our laboratory findings also exposed cryptic predatory, cooperative, and competitive interactions that impact microorganisms across fractured shales. Scaling these results from the laboratory to the field identified mechanisms underpinning biogeochemical reactions, yielding knowledge that can be harnessed to potentially increase energy yields and inform management practices in hydraulically fractured shales.