120 research outputs found

    Virginia\u27s Pfiesteria Monitoring Program: Water Quality

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    During the summer and early fall of 1998, 34 estuarine stations in Virginia were sampled for Pfiesteria like organisms (PLOs) and associated water quality conditions. Stations were sampled either bimonthly (20 stations) or monthly (14 stations) from June to October 1998. At each station, a set of live and Lugol\u27 s preserved samples were collected for presumptive counts of PLOs and water quality conditions were determined. Water quality parame­ters measured included standard field parameters, nutrients (total, dissolved, and particulate), chlorophyll a, and conventional water quality indicators. Although PLOs were relatively low in 1998 as compared to 1997, presump­tive PLO counts revealed higher PLO levels at stations located in the Northern Neck area (Potomac Embayments, Rappallannock River, and other smaller watersheds). The water quality parameters of pH, dissolved oxygen, and temperature were correlated with higher PLO counts, while several nutrients, salinity, and turbidity ,vere negatively correlated with PLOs. In the August 1997, relatively minor fish kills in the Pocomoke River and the Pocomoke Sound on the Virginia and Maryland border were attnbuted to the toxic dinoflagellate, Pfiesteria piscicida. Pfiesteria piscicida was first identified as a fish-killing dinoflagellate in fish tank at North Carolina State University (Noga et al., 1993 ). Pfiesteria piscicda has since been implicated in large widespread fish kills in North Carolina\u27s estuaries (Burkholder et al., 1992, 1995)

    Network Discovery Pipeline Elucidates Conserved Time-of-Day–Specific cis-Regulatory Modules

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    Correct daily phasing of transcription confers an adaptive advantage to almost all organisms, including higher plants. In this study, we describe a hypothesis-driven network discovery pipeline that identifies biologically relevant patterns in genome-scale data. To demonstrate its utility, we analyzed a comprehensive matrix of time courses interrogating the nuclear transcriptome of Arabidopsis thaliana plants grown under different thermocycles, photocycles, and circadian conditions. We show that 89% of Arabidopsis transcripts cycle in at least one condition and that most genes have peak expression at a particular time of day, which shifts depending on the environment. Thermocycles alone can drive at least half of all transcripts critical for synchronizing internal processes such as cell cycle and protein synthesis. We identified at least three distinct transcription modules controlling phase-specific expression, including a new midnight specific module, PBX/TBX/SBX. We validated the network discovery pipeline, as well as the midnight specific module, by demonstrating that the PBX element was sufficient to drive diurnal and circadian condition-dependent expression. Moreover, we show that the three transcription modules are conserved across Arabidopsis, poplar, and rice. These results confirm the complex interplay between thermocycles, photocycles, and the circadian clock on the daily transcription program, and provide a comprehensive view of the conserved genomic targets for a transcriptional network key to successful adaptation

    Coordinating Tissue Regeneration Through Transforming Growth Factorâ β Activated Kinase 1 Inactivation and Reactivation

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    Aberrant wound healing presents as inappropriate or insufficient tissue formation. Using a model of musculoskeletal injury, we demonstrate that loss of transforming growth factorâ β activated kinase 1 (TAK1) signaling reduces inappropriate tissue formation (heterotopic ossification) through reduced cellular differentiation. Upon identifying increased proliferation with loss of TAK1 signaling, we considered a regenerative approach to address insufficient tissue production through coordinated inactivation of TAK1 to promote cellular proliferation, followed by reactivation to elicit differentiation and extracellular matrix production. Although the current regenerative medicine paradigm is centered on the effects of drug treatment (â drug onâ ), the impact of drug withdrawal (â drug offâ ) implicit in these regimens is unknown. Because current TAK1 inhibitors are unable to phenocopy genetic Tak1 loss, we introduce the dualâ inducible COmbinational Sequential Inversion ENgineering (COSIEN) mouse model. The COSIEN mouse model, which allows us to study the response to targeted drug treatment (â drug onâ ) and subsequent withdrawal (â drug offâ ) through genetic modification, was used here to inactivate and reactivate Tak1 with the purpose of augmenting tissue regeneration in a calvarial defect model. Our study reveals the importance of both the â drug onâ (Creâ mediated inactivation) and â drug offâ (Flpâ mediated reactivation) states during regenerative therapy using a mouse model with broad utility to study targeted therapies for disease. Stem Cells 2019;37:766â 778Manipulating transforming growth factor βâ activated kinase 1 for cell and scaffold free tissue regeneration using a dualâ inducible Combinational Sequential Inversion Engineering mouse model.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149573/1/stem2991_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149573/2/stem2991.pd

    Borderline vs. unknown: comparing three-valued representations of imperfect information

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    International audienceIn this paper we compare the expressive power of elementary representation formats for vague, incomplete or conflicting information. These include Boolean valuation pairs introduced by Lawry and González-Rodríguez, orthopairs of sets of variables, Boolean possibility and necessity measures, three-valued valuations, supervaluations. We make explicit their connections with strong Kleene logic and with Belnap logic of conflicting information. The formal similarities between 3-valued approaches to vagueness and formalisms that handle incomplete information often lead to a confusion between degrees of truth and degrees of uncertainty. Yet there are important differences that appear at the interpretive level: while truth-functional logics of vagueness are accepted by a part of the scientific community (even if questioned by supervaluationists), the truth-functionality assumption of three-valued calculi for handling incomplete information looks questionable, compared to the non-truth-functional approaches based on Boolean possibility–necessity pairs. This paper aims to clarify the similarities and differences between the two situations. We also study to what extent operations for comparing and merging information items in the form of orthopairs can be expressed by means of operations on valuation pairs, three-valued valuations and underlying possibility distributions

    Adapted behavioural activation for the treatment of depression in Muslims

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    Background Incorporating religious beliefs into mental health therapy is associated with positive treatment outcomes. However, evidence about faith-sensitive therapies for minority religious groups is limited. Methods Behavioural Activation (BA), an effective psychological therapy for depression emphasising client values, was adapted for Muslim patients using a robust process that retained core effective elements of BA. The adapted intervention built on evidence synthesised from a systematic review of the literature, qualitative interviews with 29 key informants and findings from a feasibility study involving 19 patients and 13 mental health practitioners. Results Core elements of the BA model were acceptable to Muslim patients. Religious teachings could potentially reinforce and enhance BA strategies and concepts were more familiar to patients and more valued than the standard approaches. Patients appreciated therapist professionalism and empathy more than shared religious identity but did expect therapist acceptance that Islamic teachings could be helpful. Patients were generally enthusiastic about the approach, which proved acceptable and feasible to most participants; however, therapists needed more support than anticipated to implement the intervention. Limitations The study did not re-explore effectiveness of the intervention within this specific population. Strategies to address implementation issues highlighted require further research. Conclusions The adapted intervention may be more appropriate for Muslim patients than standard therapies and is feasible in practice. Therapist comfort is an important issue for services wishing to introduce the adapted therapy. The fusion of conceptual frameworks within this approach provides increased choice to Muslim patients, in line with policy and research recommendations

    Fine-scale Explosive Energy Release at Sites of Prospective Magnetic Flux Cancellation in the Core of the Solar Active Region Observed by Hi-C 2.1, IRIS, and SDO

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    The second Hi-C flight (Hi-C 2.1) provided unprecedentedly high spatial and temporal resolution (~250 km, 4.4 s) coronal EUV images of Fe ix/x emission at 172 Å of AR 12712 on 2018 May 29, during 18:56:21–19:01:56 UT. Three morphologically different types (I: dot-like; II: loop-like; III: surge/jet-like) of fine-scale sudden-brightening events (tiny microflares) are seen within and at the ends of an arch filament system in the core of the AR. Although type Is (not reported before) resemble IRIS bombs (in size, and brightness with respect to surroundings), our dot-like events are apparently much hotter and shorter in span (70 s). We complement the 5 minute duration Hi-C 2.1 data with SDO/HMI magnetograms, SDO/AIA EUV images, and IRIS UV spectra and slit-jaw images to examine, at the sites of these events, brightenings and flows in the transition region and corona and evolution of magnetic flux in the photosphere. Most, if not all, of the events are seated at sites of opposite-polarity magnetic flux convergence (sometimes driven by adjacent flux emergence), implying likely flux cancellation at the microflare's polarity inversion line. In the IRIS spectra and images, we find confirming evidence of field-aligned outflow from brightenings at the ends of loops of the arch filament system. In types I and II the explosion is confined, while in type III the explosion is ejective and drives jet-like outflow. The light curves from Hi-C, AIA, and IRIS peak nearly simultaneously for many of these events, and none of the events display a systematic cooling sequence as seen in typical coronal flares, suggesting that these tiny brightening events have chromospheric/transition region origin
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