250 research outputs found

    AN INVESTIGATION OF MICROSEISMICITY DURING THE 2018 KILAUEA CALDERA COLLAPSE

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    The 2018 Kīlauea volcano eruption and incremental caldera collapse was accompanied by more than 60,000 seismic events cataloged by the Hawaiian Volcano Observatory as well as 62 caldera collapse events that occurred roughly once per day. The majority of seismicity occurred on the eastern side of the caldera between daily collapses. However, the majority of caldera subsidence occurred to the west. To understand the collapse mechanics behind this variance in subsidence and seismicity across the caldera region, repetitive waveforms and source properties can be studied. Repeating seismic events suggest a common source that is not moving or destroyed. At Kīlauea, clusters of repeating events can indicate source processes throughout collapse cycles. REDPy, a repeating earthquake detector tool for Python, cross correlates seismic events to determine repetition. Events are separated into families or listed as orphans if no matches are found. We used data from HVO network stations surrounding Kīlauea’s summit. Possible events were identified using an STA/LTA trigger algorithm with a long-time average trigger of 8 seconds, a short-time average trigger of 1 second, and a trigger on/off range of 1-2.5. A minimum correlation coefficient of 0.7 was used to group over 167,000 recognized events from April 29th to August 2nd into nearly 6,000 families. Of these families, 697 were chosen as ‘clusters of interest’ for including \u3e100 events or persisting for 7 days or more. P-wave first-motions were manually picked for waveforms associated with clusters of interest, these clusters were then located using P-wave arrival times, and focal mechanisms were modeled for viable events to learn more about their source processes and relationship to collapse mechanics. Dilatational first motions dominate our catalog and focal mechanism models have mismatched station polarities indicative of non-double-couple sources. In fact, focal spheres show evidence of reverse motion on ring faults, which is the opposite sense of slip associated with the large, daily caldera collapse events. This change in slip direction suggests that much of the microseismicity results from shortening within the down dropped caldera and rebound in areas adjacent to the caldera

    Results of a Tracker Study Conducted Within Constructed Wetlands with Varying Cell Characteristics

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    2010 S.C. Water Resources Conferences - Science and Policy Challenges for a Sustainable Futur

    Results of an Intensive Water Quality Study of the Middle and Lower Savannah River Basin

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    2010 S.C. Water Resources Conference - Science and Policy Challenges for a Sustainable Futur

    Characterization of three Agrobacterium tumefaciens avirulent mutants with chromosomal mutations that affect induction of vir genes.

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    Three Agrobacterium tumefaciens mutants with chromosomal mutations that affect bacterial virulence were isolated by transposon mutagenesis. Two of the mutants were avirulent on all hosts tested. The third mutant, Ivr-211, was a host range mutant which was avirulent on Bryophyllum diagremontiana, Nicotiana tabacum, N. debneyi, N. glauca, and Daucus carota but was virulent on Zinnia elegans and Lycopersicon esculentum (tomato). That the mutant phenotype was due to the transposon insertion was determined by cloning the DNA containing the transposon insertion and using the cloned DNA to replace the wild-type DNA in the parent bacterial strain by marker exchange. The transposon insertions in the three mutants mapped at three widely separated locations on the bacterial chromosome. The effects of the mutations on various steps in tumor formation were examined. All three mutants showed no alteration in binding to carrot cells. However, none of the mutants showed any induction of vir genes by acetosyringone under conditions in which the parent strain showed vir gene induction. When the mutant bacteria were examined for changes in surface components, it was found that all three of the mutants showed a similar alteration in lipopolysaccharide (LPS). LPS from the mutants was larger in size and more heavily saccharide substituted than LPS from the parent strain. Two of the mutants showed no detectable alteration in outer membrane and periplasmic space proteins. The third mutant, Ivr-225, was missing a 79-kDa surface peptide. The reason(s) for the failure of vir gene induction in these mutants and its relationship, if any, to the observed alteration in LPS are unknown

    The global decline of reptiles, deja’ vu amphibians

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    Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change

    Accounting for variability when resurrecting dormant propagules substantiates their use in eco-evolutionary studies

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    There has been a steady rise in the use of dormant propagules to study biotic responses to environmental change over time. This is particularly important for organisms that strongly mediate ecosystem processes, as changes in their traits over time can provide a unique snapshot into the structure and function of ecosystems from decades to millennia in the past. Understanding sources of bias and variation is a challenge in the field of resurrection ecology, including those that arise because often-used measurements like seed germination success are imperfect indicators of propagule viability. Using a Bayesian statistical framework, we evaluated sources of variability and tested for zero-inflation and overdispersion in data from 13 germination trials of soil-stored seeds of Schoenoplectus americanus, an ecosystem engineer in coastal salt marshes in the Chesapeake Bay. We hypothesized that these two model structures align with an ecological understanding of dormancy and revival: zero-inflation could arise due to failed germinations resulting from inviability or failed attempts to break dormancy, and overdispersion could arise by failing to measure important seed traits. A model that accounted for overdispersion, but not zero-inflation, was the best fit to our data. Tetrazolium viability tests corroborated this result: most seeds that failed to germinate did so because they were inviable, not because experimental methods failed to break their dormancy. Seed viability declined exponentially with seed age and was mediated by seed provenance and experimental conditions. Our results provide a framework for accounting for and explaining variability when estimating propagule viability from soil-stored natural archives which is a key aspect of using dormant propagules in eco-evolutionary studies

    Using intervention mapping and behavior change techniques to develop a digital intervention for self-management in stroke: Development study

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    BACKGROUND: Digital therapeutics, such as interventions provided via smartphones or the internet, have been proposed as promising solutions to support self-management in persons with chronic conditions. However, the evidence supporting self-management interventions through technology in stroke is scarce, and the intervention development processes are often not well described, creating challenges in explaining why and how the intervention would work. OBJECTIVE: This study describes a specific use case of using intervention mapping (IM) and the taxonomy of behavior change techniques (BCTs) in designing a digital intervention to manage chronic symptoms and support daily life participation in people after stroke. IM is an implementation science framework used to bridge the gap between theories and practice to ensure that the intervention can be implemented in real-world settings. The taxonomy of BCTs consists of a set of active ingredients designed to change self-management behaviors. METHODS: We used the first 4 steps of the IM process to develop a technology-supported self-management intervention, interactive Self-Management Augmented by Rehabilitation Technologies (iSMART), adapted from a face-to-face stroke-focused psychoeducation program. Planning group members were involved in adapting the intervention. They also completed 3 implementation measures to assess the acceptability, appropriateness, and feasibility of iSMART. RESULTS: In step 1, we completed a needs assessment consisting of assembling a planning group to codevelop the intervention, conducting telephone surveys of people after stroke (n=125) to identify service needs, and performing a systematic review of randomized controlled trials to examine evidence of the effectiveness of digital self-management interventions to improve patient outcomes. We identified activity scheduling, symptom management, stroke prevention, access to care resources, and cognitive enhancement training as key service needs after a stroke. The review suggested that digital self-management interventions, especially those using cognitive behavioral theory, effectively reduce depression, anxiety, and fatigue and enhance self-efficacy in neurological disorders. Step 2 identified key determinants, objectives, and strategies for self-management in iSMART, including knowledge, behavioral regulation, skills, self-efficacy, motivation, negative and positive affect, and social and environmental support. In step 3, we generated the intervention components underpinned by appropriate BCTs. In step 4, we developed iSMART with the planning group members. Especially, iSMART simplified the original psychoeducation program and added 2 new components: SMS text messaging and behavioral coaching, intending to increase the uptake by people after stroke. iSMART was found to be acceptable (mean score 4.63, SD 0.38 out of 5), appropriate (mean score 4.63, SD 0.38 out of 5), and feasible (mean score 4.58, SD 0.34 out of 5). CONCLUSIONS: We describe a detailed example of using IM and the taxonomy of BCTs for designing and developing a digital intervention to support people after stroke in managing chronic symptoms and maintaining active participation in daily life

    Borrelia valaisiana resist complement-mediated killing independently of the recruitment of immune regulators and inactivation of complement components

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    Spirochetes belonging to the Borrelia (B.) burgdorferi sensu lato complex differ in their resistance to complement-mediated killing, particularly in regard to human serum. In the present study, we elucidate the serum and complement susceptibility of B. valaisiana, a genospecies with the potential to cause Lyme disease in Europe as well as in Asia. Among the investigated isolates, growth of ZWU3 Ny3 was not affected while growth of VS116 and Bv9 was strongly inhibited in the presence of 50% human serum. Analyzing complement activation, complement components C3, C4 and C6 were deposited on the surface of isolates VS116 and Bv9, and similarly the membrane attack complex was formed on their surface. In contrast, no surface-deposited components and no aberrations in cell morphology were detected for serum-resistant ZWU3 Ny3. While further investigating the protective role of bound complement regulators in mediating complement resistance, we discovered that none of the B. valaisiana isolates analyzed bound complement regulators Factor H, Factor H-like protein 1, C4b binding protein or C1 esterase inhibitor. In addition, B. valaisiana also lacked intrinsic proteolytic activity to degrade complement components C3, C3b, C4, C4b, and C5. Taken together, these findings suggest that certain B. valaisiana isolates differ in their capability to resist complement-mediating killing by human serum. The molecular mechanism utilized by B. valaisiana to inhibit bacteriolysis appears not to involve binding of the key host complement regulators of the alternative, classical, and lectin pathways as already known for serum-resistant Lyme disease or relapsing fever borreliae

    Borrelia burgdorferi EbfC defines a newly-identified, widespread family of bacterial DNA-binding proteins

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    The Lyme disease spirochete, Borrelia burgdorferi, encodes a novel type of DNA-binding protein named EbfC. Orthologs of EbfC are encoded by a wide range of bacterial species, so characterization of the borrelial protein has implications that span the eubacterial kingdom. The present work defines the DNA sequence required for high-affinity binding by EbfC to be the 4 bp broken palindrome GTnAC, where ‘n’ can be any nucleotide. Two high-affinity EbfC-binding sites are located immediately 5′ of B. burgdorferi erp transcriptional promoters, and binding of EbfC was found to alter the conformation of erp promoter DNA. Consensus EbfC-binding sites are abundantly distributed throughout the B. burgdorferi genome, occurring approximately once every 1 kb. These and other features of EbfC suggest that this small protein and its orthologs may represent a distinctive type of bacterial nucleoid-associated protein. EbfC was shown to bind DNA as a homodimer, and site-directed mutagenesis studies indicated that EbfC and its orthologs appear to bind DNA via a novel α-helical ‘tweezer’-like structure

    A megbocsátás pszichológiája: kialakulása, hatásai és fejlesztése

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    A megbocsátás az interperszonális sérelmekre adott egyik lehetséges válasznak tekinthető, melynek fókuszában a sérelmet elszenvedő személy kognitív, érzelmi és viselkedéses válaszaiban bekövetkező proszociális változás áll. A megbocsátás mentális és fizikai egészségre kifejtett pozitív hatása jól dokumentált. Magas szintje alacsony szorongás- és depressziószinttel társul, illetve sikeresen csökkenti a stresszre adott fizikai választ (kortizol és kardiovaszkuláris reaktivitás). A megbocsátást - hatásai alapján - olyan emóció fókuszú megküzdési módként definiálhatjuk, mely sikeresen csökkenti az interperszonális sérelem nyomán kialakult stresszreakciót. Az utóbbi években számos intervenciós technikát dolgoztak ki, melyek a megbocsátás támogatását, illetve fejlesztését tűzték ki célként. Ezek a módszerek általában sikeresen növelik a megbocsátásra való hajlandóságot.</o:p
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