1,507 research outputs found

    Sources, mechanisms, and timescales of sediment delivery to a New England salt marsh

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baranes, H., Woodruff, J., Geyer, W., Yellen, B., Richardson, J. & Griswold, F. Sources, mechanisms, and timescales of sediment delivery to a New England salt marsh. Journal of Geophysical Research: Earth Surface, 127, (2022): e2021JF006478, https://doi.org/10.1029/2021jf006478.he availability and delivery of an external clastic sediment source is a key factor in determining salt marsh resilience to future sea level rise. However, information on sources, mechanisms, and timescales of sediment delivery are lacking, particularly for wave-protected mesotidal estuaries. Here we show that marine sediment mobilized and delivered during coastal storms is a primary source to the North and South Rivers, a mesotidal bar-built estuary in a small river system impacted by frequent, moderate-intensity storms that is typical to New England (United States). On the marsh platform, deposition rates, clastic content, and dilution of fluvially-sourced contaminated sediment by marine material all increase down-estuary toward the inlet, consistent with a predominantly marine-derived sediment source. Marsh clastic deposition rates are also highest in the storm season. We observe that periods of elevated turbidity in channels and over the marsh are concurrent with storm surge and high wave activity offshore, rather than with high river discharge. Flood tide turbidity also exceeds ebb tide turbidity during storm events. Timescales of storm-driven marine sediment delivery range from 2.5 days to 2 weeks, depending on location within the estuary; therefore the phasing of storm surge and waves with the spring-neap cycle determines how effectively post-event suspended sediment is delivered to the marsh platform. This study reveals that sediment supply and the associated resilience of New England mesotidal salt marshes involves the interplay of coastal and estuarine processes, underscoring the importance of looking both up- and downstream to identify key drivers of environmental change.The project described in this publication was in part supported by Grant or Cooperative Agreement No. G20AC00071 from the U.S. Geological Survey and a Department of Interior Northeast Climate Adaptation Science Center graduate fellowship awarded to H.E.B (G12AC00001)

    New genus Volborattella.

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    71 pages : illustrations (some color), maps (some color) ; 26 cm. "Species descriptions were generated with the aid of the oonopid PBI descriptive database"--Page 10.A new genus of goblin spider from Madagascar, Volborattella Saucedo and Ubick, is proposed and its five included species newly described and illustrated: V. teresae, the type species, V. guenevera, V. nasario, V. paulyi, and V. toliara. These species differ from other oonopids in several unusual characters, especially the variously modified setae: abdominal scutes having thick recumbent setae with large bases and conspicuous pits; the pedicel region with mats of plumose setae and associated cuticular projections; and anterior metatarsi with prolateral combs. The male palp of Volborattella appears to be unique in having a terminal projection (embolar superior prong, ESP) that forms an abrupt spiral and the female a receptaculum with an accessory duct (curved tube). Volborattella resemble members of the Gamasomorpha complex in lacking leg spines and having a flattened abdomen with complete scutes, but differ genitalically. The Volborattella female has a receptaculum that is wider than long (as opposed to longer than wide in the Gamasomorpha complex) and the male has the embolar region sharply bent (as opposed to evenly curved), which places the genus in the Pelicinus complex. The relationship of Volborattella to other pelicinoids is not resolved. Although the genus most closely resembles some Silhouettella Benoit, Noideattella Álvarez-Padilla et al. and Lionneta Benoit in various genitalic features, somatically it shares with Tolegnaro Álvarez-Padilla et al. and two undescribed Malagasy genera the gamasomorphoid body form and plumose setae. Volborattella females are unusual in having antisymmetrical internal genitalia, with the CTs occurring in either a left or right position, and that these differences in handedness (antisymmetry) are evenly distributed. The shape and size of the CT, as examined through light and scanning microscopy, suggest that it is a coupling pocket for the ESP; if so, Volborattella females are either righties or lefties in their palpal preference

    Prediabetes and Diabetes Are Associated With Arterial Stiffness in Older Adults: The ARIC Study

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    To determine whether prediabetes and diabetes in older adults are associated with arterial stiffness measured in central and peripheral arteries and to examine characteristics that modify these associations

    A Comparative Study of the ReCellÂź Device and Autologous Spit-Thickness Meshed Skin Graft in the Treatment of Acute Burn Injuries.

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    Early excision and autografting are standard care for deeper burns. However, donor sites are a source of significant morbidity. To address this, the ReCellÂź Autologous Cell Harvesting Device (ReCell) was designed for use at the point-of-care to prepare a noncultured, autologous skin cell suspension (ASCS) capable of epidermal regeneration using minimal donor skin. A prospective study was conducted to evaluate the clinical performance of ReCell vs meshed split-thickness skin grafts (STSG, Control) for the treatment of deep partial-thickness burns. Effectiveness measures were assessed to 1 year for both ASCS and Control treatment sites and donor sites, including the incidence of healing, scarring, and pain. At 4 weeks, 98% of the ASCS-treated sites were healed compared with 100% of the Controls. Pain and assessments of scarring at the treatment sites were reported to be similar between groups. Significant differences were observed between ReCell and Control donor sites. The mean ReCell donor area was approximately 40 times smaller than that of the Control (P < .0001), and after 1 week, significantly more ReCell donor sites were healed than Controls (P = .04). Over the first 16 weeks, patients reported significantly less pain at the ReCell donor sites compared with Controls (P ≀ .05 at each time point). Long-term patients reported higher satisfaction with ReCell donor site outcomes compared with the Controls. This study provides evidence that the treatment of deep partial-thickness burns with ASCS results in comparable healing, with significantly reduced donor site size and pain and improved appearance relative to STSG

    Covert Neurological Symptoms Associated With Silent Infarcts From Midlife to Older Age: The Atherosclerosis Risk in Communities Study

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    Unrecognized or unreported stroke-like symptoms, called covert symptoms, occur in persons free of clinical stroke. Whether covert symptoms are associated with subclinical brain infarcts (SBI) is unknown. This study examined the association between covert stroke-like symptoms and SBI/stroke in persons with no history of stroke or TIA

    Operationalizing Frailty in the Atherosclerosis Risk in Communities Study Cohort

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    Background: Factors that may contribute to the development of frailty in late life have not been widely investigated. The Atherosclerosis Risk in Communities (ARIC) Study cohort presents an opportunity to examine relationships of midlife risk factors with frailty in late life. However, we first present findings on the validation of an established frailty phenotype in this predominantly biracial population of older adults. Methods: Among 6,080 participants, we defined frailty based upon the Cardiovascular Health Study (CHS) criteria incorporating measures of weight loss, exhaustion, slow walking speed, low physical activity, and low grip strength. Criterion and predictive validity of the frailty phenotype were estimated from associations between frailty status and participants' physical and mental health status, physiologic markers, and incident clinical outcomes. Results: A total of 393 (6.5%) participants were classified as frail and 50.4% pre-frail, similar to CHS (6.9% frail, 46.6% pre-frail). In age-adjusted analyses, frailty was concurrently associated with depressive symptoms, low self-rated health, low medication adherence, and clinical biomarker levels (ie, cholesterol, hemoglobin A1c, white blood cell count, C-reactive protein, and hemoglobin). During 1-year follow-up, frailty was associated with falls, low physical ability, fatigue, and mortality. Conclusions: These findings support the validity of the CHS frailty phenotype in the ARIC Study cohort. Future studies in ARIC may elucidate early-life exposures that contribute to late-life frailty

    Gender-Sensitive Violence Risk Assessment:Predictive Validity of Six Tools in Female Forensic Psychiatric Patients

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    Most violence risk assessment tools have been validated predominantly in males. In this multicenter study, the Historical, Clinical, Risk Management-20 (HCR-20), Historical, Clinical, Risk Management-20 Version 3 (HCR-20(V3)), Female Additional Manual (FAM), Short-Term Assessment of Risk and Treatability (START), Structured Assessment of Protective Factors for violence risk (SAPROF), and Psychopathy Checklist-Revised (PCL-R) were coded on file information of 78 female forensic psychiatric patients discharged between 1993 and 2012 with a mean follow-up period of 11.8 years from one of four Dutch forensic psychiatric hospitals. Notable was the high rate of mortality (17.9%) and readmission to psychiatric settings (11.5%) after discharge. Official reconviction data could be retrieved from the Ministry of Justice and Security for 71 women. Twenty-four women (33.8%) were reconvicted after discharge, including 13 for violent offenses (18.3%). Overall, predictive validity was moderate for all types of recidivism, but low for violence. The START Vulnerability scores, HCR-20(V3), and FAM showed the highest predictive accuracy for all recidivism. With respect to violent recidivism, only the START Vulnerability scores and the Clinical scale of the HCR-20(V3) demonstrated significant predictive accuracy

    A direct path to dependable software

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    What would it take to make software more dependable? Until now, most approaches have been indirect: some practices – processes, tools or techniques – are used that are believed to yield dependable software, and the argument for dependability rests on the extent to which the developers have adhered to them. This article argues instead that developers should produce direct evidence that the software satisfies its dependability claims. The potential advantages of this approach are greater credibility (since the argument is not contingent on the effectiveness of the practices) and reduced cost (since development resources can be focused where they have the most impact)
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