209 research outputs found

    Experimental Watersheds at Coshocton, Ohio, USA: Experiences and Establishing New Experimental Watersheds

    Get PDF
    The North Appalachian Experimental Watershed (NAEW) in Ohio was established in 1935 to improve economical and physical sustainability in agriculture. The objectives were to test management practices on small watersheds, investigate scaling of runoff and erosion to larger areas, and research ways to extrapolate the results to ungauged areas. The facility was equipped with a permanent infrastructure consisting of runoff stations and rain gauges for watersheds ranging in size from 0.26 to 1854 ha, and 11 large (0.008 ha) monolith lysimeters to investigate small-scale water balances, all in an area greater than 2000 ha. After about 1970, the NAEW was reduced in size to 425 ha consisting of mostly small watersheds (“test beds”) ranging in size from 0.26 to 3.07 ha. The NAEW was in operation for approximately 81 years generating a long record of runoff and other data for various watersheds, and closed in 2015. A wide variety of experiments were conducted on the NAEW with many high-impact accomplishments and addressing emerging issues that founders never envisioned. Nearly, 500 publications came from investigations during the history of the facility, and insights for establishing new experimental watersheds are presented covering site selection, funding, site specificity, extrapolation of results, generation of runoff in different physiographic regions, collaboration, off-site investigations, and instrumentation. The research on water quality was added to the research objectives in the 1970s, including nutrients (nitrogen and phosphorus) and pesticides in surface runoff and subsurface flow

    The Original USDA-ARS Experimental Watersheds in Texas and Ohio: Contributions from the Past and Visions for the Future

    Get PDF
    The USDA Soil Conservation Service (USDA‐SCS) realized the importance of understanding hydrologic processes on agricultural fields and watersheds in the mid‐1930s. Based on this realization, the research program of the Hydrologic Division of SCS established three experimental watersheds across the U.S. to analyze the impact of landuse practices on soil erosion, flood events, water resources, and the agricultural economy. Two of the original watersheds remain in operation today within the USDA Agricultural Research Service (USDA‐ARS): the Blacklands Experimental Watershed (now the Grassland, Soil and Water Research Laboratory) near Riesel, Texas, and the North Appalachian Experimental Watershed near Coshocton, Ohio. These original watersheds were designed for collection of hydrologic data on small watersheds and evaluation of hydrologic and soil loss response as influenced by various agricultural land management practices. A major contribution of these experimental watersheds is the quantification of soil loss reduction under conservation management, which has led to a drastic reduction in soil loss from cultivated agriculture in the 20th century. Riesel watershed studies produced the scientific basis for several watershed models that are now used worldwide to manage water quality and also facilitated fundamental analysis of the agronomic and environmental effects of tillage, fertilizer, and pesticide alternatives. Coshocton watershed studies led to the development of no‐till and pasture management practices to control runoff, erosion, and chemical loss and were instrumental in understanding water quality and hydrologic effects of soil macropores and mining and reclamation activities. The long‐term hydrologic records at each site have also improved understanding and management of water resources in their respective geographic regions. Because of their historical and future value, the USDA‐ARS has a unique responsibility to maintain these long‐term experimental watersheds, which are vital for addressing emerging research needs to meet future water availability, environmental quality, and food and fiber demands

    Travelling and sticky affects: : Exploring teens and sexualized cyberbullying through a Butlerian-Deleuzian- Guattarian lens

    Get PDF
    In this paper we combine the thinking of Deleuze and Guattari (1984, 1987) with Judith Butler’s (1990, 1993, 2004, 2009) work to follow the rhizomatic becomings of young people’s affective relations in a range of on- and off-line school spaces. In particular we explore how events that may be designated as sexual cyberbullying are constituted and how they are mediated by technology (such as texting or in/through social networking sites). Drawing on findings from two different studies looking at teens’ uses of and experiences with social networking sites, Arto in Denmark, and Bebo in the UK, we use this approach to think about how affects flow, are distributed, and become fixed in assemblages. We map how affects are manoeuvred and potentially disrupted by young people, suggesting that in the incidences discussed affects travel as well as stick in points of fixation. We argue that we need to grasp both affective flow and fixity in order to gain knowledge of how subjectification of the gendered/classed/racialised/sexualised body emerges. A Butlerian-Deleuzian-Guattarian frame helps us to map some of these affective complexities that shape sexualized cyberbully events; and to recognize technologically mediated lines of flight when subjectifications are at least temporarily disrupted and new terms of recognition and intelligibility staked out. Keywords

    Bronchial Thermoplasty Induced Airway Smooth Muscle Reduction and Clinical Response in Severe Asthma:The TASMA Randomized Trial

    Get PDF
    RATIONALE: Bronchial Thermoplasty (BT) is a bronchoscopic treatment for severe asthma targeting airway smooth muscle (ASM). Observational studies have shown ASM mass reduction after BT but appropriate control groups are lacking. Furthermore, as treatment response is variable, identifying optimal candidates for BT treatment is important. AIMS: First, to assess the effect of BT on ASM mass and second, to identify patient characteristics that correlate with BT-response. METHODS: Severe asthma patients (n=40) were randomized to immediate (n=20) or delayed (n=20) BT-treatment. Prior to randomization, clinical, functional, blood and airway biopsy data were collected. In the delayed control group, re-assessment, including biopsies, was performed after 6 months of standard clinical care, followed by BT. In both groups, post-BT data including biopsies were obtained after 6 months. ASM mass (% positive desmin or α-smooth muscle actin area in the total biopsy) was calculated with automated digital analyses software. Associations between baseline characteristics and Asthma Control and Asthma Quality of Life Questionnaire (ACQ/AQLQ) improvement were explored. RESULTS: Median ASM mass decreased by >50% in the immediate BT group (n=17) versus no change in the delayed control group (n=19) (p=0.0004). In the immediate group ACQ scores improved with -0.79 (-1.61;0.02 IQR) compared to 0.09 (-0.25;1.17 IQR) in the delayed group (p=0.006). AQLQ scores improved with 0.83 (-0.15;1.69 IQR) versus -0.02 (-0.77;0.75 IQR) (p=0.04). Treatment response in the total group (n=35) was positively associated with serum IgE and eosinophils, but not with baseline ASM mass. CONCLUSION: ASM mass significantly decreases after BT when compared to a randomized non-BT treated control group. Treatment response was associated with serum IgE and eosinophil levels but not with ASM mass. Clinical trial registration available at www.clinicaltrials.gov, ID:NCT0222539

    Endobronchial ultrasound for T4 staging in patients with resectable NSCLC

    Get PDF
    Background: In lung cancer patients, accurate assessment of mediastinal and vascular tumor invasion (stage T4) is crucial for optimal treatment allocation and to prevent unnecessary thoracotomies. We assessed the diagnostic accuracy of linear endobronchial ultrasound (EBUS) for T4-status in patients with centrally located lung cancer.Methods: This is a retrospective study among consecutive patients who underwent EBUS for diagnosis and staging of lung cancer in four hospitals in The Netherlands (Amsterdam, Leiden), Italy (Bologna) and Poland (Zakopane) between 04-2012 and 04-2019. Patients were included if the primary tumor was detected by EBUS and subsequent surgical-pathological staging was performed, which served as the reference standard. T4-status was extracted from EBUS and pathology reports. Chest CT's were re-reviewed for T4-status.Results: 104 patients with lung cancer in whom EBUS detected the primary tumour, and who underwent subsequent surgical-pathological staging were included. 36 patients (35 %) had T4-status, based on vascular (n = 17), mediastinal (n = 15), both vascular and mediastinal (n = 3), or oesophageal invasion (n = 1). For EBUS, sensitivity, specificity, PPV and NPV for T4-status were (n = 104): 63.9 % (95 %CI 46.2-79.2 %), 92.6 % (83.7-97.6 %), 82.1 % (65.6-91.7 %), and 82.9 % (75.7-88.2 %), respectively. For chest CT (n = 72): 61.5 % (95 %CI 40.6-79.8 %), 37.0 % (23.2-52.5 %), 35.6 % (27.5-44.6 %), and 63.0 % (47.9-75.9 %), respectively. When combining CT and EBUS with concordant T4 status (n = 33): 90.9 % (95 %CI 58.7-99.8 %), 77.3 % (54.6-92.20 %), 66.7 % (47.5-81.6 %), and 94.4 % (721-99.1%), respectively.Conclusion: Both EBUS and CT alone are inaccurate for assessing T4-status as standalone test. However, combining a negative EBUS with a negative CT may rule out T4-status with high certainty.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas

    A slow bar in the lenticular barred galaxy NGC 4277

    Get PDF
    Aims. We characterised the properties of the bar hosted in lenticular galaxy NGC 4277, which is located behind the Virgo cluster. Methods. We measured the bar length and strength from the surface photometry obtained from the broad-band imaging of the Sloan Digital Sky Survey and we derived the bar pattern speed from the stellar kinematics obtained from the integral-field spectroscopy performed with the Multi Unit Spectroscopic Explorer at the Very Large Telescope. We also estimated the co-rotation radius from the circular velocity, which we constrained by correcting the stellar streaming motions for asymmetric drift, and we finally derived the bar rotation rate. Results. We found that NGC 4277 hosts a short (Rbar = 3.2 +0.9 −0.6 kpc), weak (S bar = 0.21 ± 0.02), and slow (R = 1.8 +0.5 −0.3) bar and its pattern speed (℩bar = 24.7 ± 3.4 km s−1 kpc−1) is amongst the best-constrained ones ever obtained with the Tremaine-Weinberg (TW) method with relative statistical errors of ∌ 0.2. Conclusions. NGC 4277 is the first clear-cut case of a galaxy hosting a slow stellar bar (R > 1.4 at more than a 1σ confidence level) measured with the model-independent TW method. A possible interaction with the neighbour galaxy NGC 4273 could have triggered the formation of such a slow bar and/or the bar could be slowed down due to the dynamical friction with a significant amount of dark matter within the bar region

    Standardized research protocols enable transdisciplinary research of climate variation impacts in corn production systems

    Get PDF
    The important questions about agriculture, climate, and sustainability have become increasingly complex and require a coordinated, multifaceted approach for developing new knowledge and understanding. A multistate, transdisciplinary project was begun in 2011 to study the potential for both mitigation and adaptation of corn-based cropping systems to climate variations. The team is measuring the baseline as well as change of the system\u27s carbon (C), nitrogen (N), and water footprints, crop productivity, and pest pressure in response to existing and novel production practices. Nine states and 11 institutions are participating in the project, necessitating a well thought out approach to coordinating field data collection procedures at 35 research sites. In addition, the collected data must be brought together in a way that can be stored and used by persons not originally involved in the data collection, necessitating robust procedures for linking metadata with the data and clearly delineated rules for use and publication of data from the overall project. In order to improve the ability to compare data across sites and begin to make inferences about soil and cropping system responses to climate across the region, detailed research protocols were developed to standardize the types of measurements taken and the specific details such as depth, time, method, numbers of samples, and minimum data set required from each site. This process required significant time, debate, and commitment of all the investigators involved with field data collection and was also informed by the data needed to run the simulation models and life cycle analyses. Although individual research teams are collecting additional measurements beyond those stated in the standardized protocols, the written protocols are used by the team for the base measurements to be compared across the region. A centralized database was constructed to meet the needs of current researchers on this project as well as for future use for data synthesis and modeling for agricultural, ecosystem, and climate sciences

    Space Telescope and Optical Reverberation Mapping Project. VI. : reverberating disk models for NGC 5548

    Get PDF
    D.A.S. and K.D.H. acknowledge support from the UK Science and Technology Facilities Council through grant ST/K502339/1 and ST/J001651/1.We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light curves (1158 Å to 9157 Å) combine simultaneous Hubble Space Telescope, Swift, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination i = 36° ± 10°, temperature T1 =(44 ± 6) x 103 K at 1 light day from the black hole, and a temperature–radius slope (T α r-α) of α = 0.99 ± 0.03. We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at L/LEdd=0.1.PostprintPeer reviewe

    Space telescope and optical reverberation mapping project. IV. Anomalous behavior of the broad ultraviolet emission lines in NGC 5548

    Get PDF
    During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far UV continuum and broad emission line variations decorrelated for ∌60-70 days, starting ∌75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, characterized by significant deficits in flux and equivalent width of the strong broad UV emission lines, is the first of its kind to be unambiguously identified in an active galactic nucleus reverberation mapping campaign. The largest corresponding emission line flux deficits occurred for the high ionization, collisionally excited lines C iv and Si iv(+O iv]), and also He ii(+O iii]), while the anomaly in Lywas substantially smaller. This pattern of behavior indicates a depletion in the flux of photons with Eph > 54 eV relative to those near 13.6 eV. We suggest two plausible mechanisms for the observed behavior: (i) temporary obscuration of the ionizing continuum incident upon broad line region (BLR) clouds by a moving veil of material lying between the inner accretion disk and inner (BLR), perhaps resulting from an episodic ejection of material from the disk, or (ii) a temporary change in the intrinsic ionizing continuum spectral energy distribution resulting in a deficit of ionizing photons with energies >54 eV, possibly due to a transient restructuring of the Comptonizing atmosphere above the disk. Current evidence appears to favor the latter explanation.Publisher PDFPeer reviewe

    AGN STORM 2. IV. Swift X-ray and ultraviolet/optical monitoring of Mrk 817

    Full text link
    The AGN STORM 2 campaign is a large, multiwavelength reverberation mapping project designed to trace out the structure of Mrk 817 from the inner accretion disk to the broad emission line region and out to the dusty torus. As part of this campaign, Swift performed daily monitoring of Mrk 817 for approximately 15 months, obtaining observations in X-rays and six UV/optical filters. The X-ray monitoring shows that Mrk 817 was in a significantly fainter state than in previous observations, with only a brief flare where it reached prior flux levels. The X-ray spectrum is heavily obscured. The UV/optical light curves show significant variability throughout the campaign and are well correlated with one another, but uncorrelated with the X-rays. Combining the Swift UV/optical light curves with Hubble UV continuum light curves, we measure interband continuum lags, τ(λ)\tau(\lambda), that increase with increasing wavelength roughly following τ(λ)∝λ4/3\tau(\lambda) \propto \lambda^{4/3}, the dependence expected for a geometrically thin, optically thick, centrally illuminated disk. Modeling of the light curves reveals a period at the beginning of the campaign where the response of the continuum is suppressed compared to later in the light curve - the light curves are not simple shifted and scaled versions of each other. The interval of suppressed response corresponds to a period of high UV line and X-ray absorption, and reduced emission line variability amplitudes. We suggest that this indicates a significant contribution to the continuum from the broad line region gas that sees an absorbed ionizing continuum.Comment: 20 pages, 13 figures, 3 tables, accepted for publication in Ap
    • 

    corecore