1,662 research outputs found
Human activity and demographics drive the fire regime in a highly developed European boreal region
Organization of successful wildfire prevention and suppression require detailed information on ignition causes, size distributions and relations to weather. From a large and highly detailed dataset of Swedish wildfire incidents (n = 124 000) we assess temporal, geographical and human-related patterns over a 25-year-period (1996-2020). We find strong positive correlations between population density and wildfire occurrence, primarily caused by a wide spectrum of human activities. However, fires >10 ha mostly occurred in sparsely populated regions and were more often ignited by lightning or heavy machinery. Further, large fires had a history of long response times and insufficient mop-up, in turn intimately linked to low population density. We detect no trend over the 25-year-period in either fire weather, number of ignitions or burned area, but a dramatic decline in wildfire caused by children's play as well as by springtime burning of dead grass, a traditional fire use in rural areas. Our results indicate that irrespective of climate change, societal changes such as rural depopulation and cultural shifts are imminently important for the future fire regime in this intensely managed part of the boreal, and may warrant more attention worldwide
Clinical Decision-Making of Nurses Regarding Elder Abuse
A descriptive correlational design based on an adapted model of Donabedian’s Structure, Process, Outcome model and Benner’s Novice to Expert theory was used to examine the clinical decision-making of nurses regarding elder abuse. The relationship of the nurses applied knowledge (assessment cues) of elder abuse; demographic questions (e.g. years of experience as a Registered Nurse (RN) and their clinical level of practice status), the use of intuition in nursing practice; and clinical decision outcomes (interventions) for patients in cases of suspected elder abuse was examined. A convenience sample of RNs who worked in the emergency department (ED) in three acute care hospitals, in southeastern United States were asked to complete questionnaires on education about elder abuse, their intuition use, demographic information, applied knowledge of elder abuse, and clinical decision outcomes for suspected elder abuse. The majority of the nurses had participated in the clinical level of practice status program.The convenience sample of 84 RNs consisted of 68 females (81%) and 16 males (19%). The average age of the respondents was 41.43 years. The mean number of years worked as a RN was 13.87 years. Multiple regression results indicated an overall model of two predictors (RNs applied knowledge (assessment cues) and years worked as a RN) significantly predicted clinical decision outcomes (interventions). The model accounted for 25.1% variance in clinical decision outcomes. The t-test revealed there was no difference (applied knowledge (assessment cues) of elder abuse, intuition use in nursing, years working as a RN, clinical level of practice status, and clinical decision outcomes (interventions)) between RNs who received elder abuse education at orientation and those who did not receive the education. The study results suggest that years of working as a nurse supported elder abuse recognition and intervention. The clinical level of practice status of nurses was found not to be a sensitive indicator. Elder abuse education during orientation varied between the hospital settings. The results indicate the educational need for nurses regarding suspected elder abuse
An Analytic Framework for Design-Oriented Research Concepts
Over the last few decades, the field of information systems has shown a steadily increasing interest in design-oriented research. This is manifested through the emergence of different ontological and epistemological positions among IS researchers. Some challenges arise from this development, such as (a) a need to understand design-oriented IS research in relation to design-oriented approaches in other disciplines, and (b) a need for design theory representation that targets and is useful to stakeholders in both research and practice. This paper proposes a conceptual framework for understanding designoriented research, and its implications for research with a focus on meeting the two challenges mentioned above
Investigation of the limits of nanoscale filopodial interactions
Mesenchymal stem cells are sensitive to changes in feature height, order and spacing. We had previously noted that there was an inverse relationship between osteoinductive potential and feature height on 15-, 55- and 90 nm-high titania nanopillars, with 15 nm-high pillars being the most effective substrate at inducing osteogenesis of human mesenchymal stem cells. The osteoinductive effect was somewhat diminished by decreasing the feature height to 8 nm, however, which suggested that there was a cut-off point, potentially associated with a change in cell–nanofeature interactions. To investigate this further, in this study, a scanning electron microscopy/three-dimensional scanning electron microscopy approach was used to examine the interactions between mesenchymal stem cells and the 8 and 15 nm nanopillared surfaces. As expected, the cells adopted a predominantly filopodial mode of interaction with the 15 nm-high pillars. Interestingly, fine nanoscale membrane projections, which we have termed ‘nanopodia,’ were also employed by the cells on the 8 nm pillars, and it seems that this is analogous to the cells ‘clinging on with their fingertips’ to this scale of features
Aridification of Central Asia and uplift of the Altai and Hangay mountains, Mongolia: stable isotope evidence
Central Asia has become increasingly arid during the Cenozoic, though the mechanisms behind this aridification remain unresolved. Much attention has focused on the influence and uplift history of the Tibetan Plateau. However, the role of ranges linked to India-Asia convergence but well north of the Plateau—including the Altai, Sayan, and Hangay—in creating the arid climate of Central Asia is poorly understood. Today, these ranges create a prominent rain shadow, effectively separating the boreal forest to the north from the deserts of Central Asia. To explore the role of these mountains in modifying climate since the late Eocene, we measured carbon and oxygen stable isotopes in paleosol carbonates from three basins along a 650 km long transect at the northern edge of the Gobi Desert in Mongolia and in the lee of the Altai and Hangay mountains. We combine these data with modern air-parcel back-trajectory modeling to understand regional moisture transport pathways at each basin. In all basins, δ¹³C increases, with the largest increase in western Mongolia. The first δ¹³C increase occurs in central and southwestern Mongolia in the Oligocene. δ¹³C again increases from the upper Miocene to the Quaternary in western and southwestern Mongolia. We use a 1-D soil diffusion model to demonstrate that these δ¹³C increases are linked to declines in soil respiration driven by dramatic increases in aridity. Using modern-day empirical relations between mean annual precipitation and soil respiration, we estimate that precipitation has likely more than halved over the Neogene. Given the importance of the Hangay and Altai in steering moisture in Mongolia, we attribute these changes to differential surface uplift of the Hangay and Altai. Surface uplift in the Hangay began by the early Oligocene, blocking Siberian moisture and aridifying the northern Gobi. In contrast, surface uplift of the Altai began in the late Miocene, blocking moisture from reaching western Mongolia. Thus, the northern Gobi became increasingly arid east to west since the late Eocene, likely driven by orographic development in the Hangay during the Oligocene and the Altai in the late Miocene through Pliocene
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Informing and Enhancing Scientific and Management Understanding of Oregon’s Nearshore Groundfish Trawl Fishery by Engaging Local Ecological Knowledge
Oregon’s Coastal nearshore ecosystems are a nexus between living marine resources and coincident human recreational, industrial and socio-economic development. These nearshore regions also provide habitats vital to early life history stages of commercial non-whiting groundfish species, which supplied 21% of the Oregon fishing economy in 2018. The very shallow portions of the Oregon Coast (the area of the shelf inshore of ~30fm (180 ft or 55m) have been the subject of little to no scientific survey monitoring, and much of the details of the ecology, health and processes in these habitats remain poorly understood. Furthermore, while the activity of the offshore Pacific Whiting (Merluccius productus) fleet and deeper water demersal fisheries have remained more consistent from 1976-present, the nearshore sector (which for the purposes of this thesis is defined as the region of shelf extending seaward to a water depth of 110 fathoms (200 meters or 660 feet)), has become increasingly underutilized by the Oregon commercial groundfish trawl fleet. This thesis assesses the potential for a more comprehensive reconstruction and understanding of broad-timescale trawl effort in the Oregon nearshore to be extracted from the combined knowledge of the commercial fishing community, fisheries managers, and fisheries scientists. By better defining what has impacted Oregon’s small nearshore fleet members, this thesis explores whether the collective experiences of fishermen in the nearshore sector through time may contribute local ecological knowledge (LEK) to lesser-studied groundfish fishery habitats in Oregon. Fisheries-dependent data were collected in the form of commercial trawl logbooks, fishticket landings, and industry interviews and assessed using mixed quantitative and qualitative methods. Results expose the nearshore sector of Oregon’s groundfish trawl fishery as a niche fishery recovering from a 20-year period of management reform and fisheries rebuilding. Less tangibly, it recognizes the self-contained identity of a small, specialized subset of the broader Oregon groundfish trawl fleet, whose endemic knowledge and experiences of the nearshore shelf prove valuable to reconstructing the history and social-constructs of the unique nearshore ecosystem. The experiential knowledge and consistency in exposure of the nearshore groundfish trawl fleet offer a detailed and long-standing record of the drivers and health of the groundfish fishery both spatially and temporally. Findings from this research provide an opportunity to utilize LEK to augment scientific ecological knowledge (SEK). Adopting the LEK and contacts established within the Oregon nearshore groundfish fleet from this thesis establishes a baseline for ongoing conversations, cooperation and prospective collaboration among scientists, fisheries managers and fishermen moving forward
Effects of the sodium-glucose co-transporter-2 inhibitor dapagliflozin on estimated plasma volume in patients with type 2 diabetes
Aims To compare the effects of the sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin on estimated (ePV) and measured plasma volume (mPV) and to characterize the effects of dapagliflozin on ePV in a broad population of patients with type 2 diabetes. Materials and methods The Strauss formula was used to calculate changes in ePV. Change in plasma volume measured with I-125-human serum albumin (mPV) was compared with change in ePV in 10 patients with type 2 diabetes randomized to dapagliflozin 10 mg/d or placebo. Subsequently, changes in ePV were measured in a pooled database of 13 phase 2b/3 placebo-controlled clinical trials involving 4533 patients with type 2 diabetes who were randomized to dapagliflozin 10 mg daily or matched placebo. Results The median change in ePV was similar to the median change in mPV (-9.4% and -9.0%) during dapagliflozin treatment. In the pooled analysis of clinical trials, dapagliflozin decreased ePV by 9.6% (95% confidence interval 9.0 to 10.2) compared to placebo after 24 weeks. This effect was consistent in various patient subgroups, including subgroups with or without diuretic use or established cardiovascular disease. Conclusions ePV may be used as a proxy to assess changes in plasma volume during dapagliflozin treatment. Dapagliflozin consistently decreased ePV compared to placebo in a broad population of patients with type 2 diabetes
Influence of Fiber-Bragg Grating-Induced Group-Delay Ripple in High-Speed Transmission Systems
The implementation of a chirped fiber-Bragg grating (FBG) for dispersion compensation in high-speed (up to 120 Gbit/s) transmission systems with differential and coherent detection is, for the first time, experimentally investigated. For systems with differential detection, we examine the influence of group-delay ripple (GDR) in 40 GBd 2-, 4-, and 8-ary differential phase shift keying (DPSK) systems. Furthermore, we conduct a nonlinear-tolerance comparison between the systems implementing dispersion-compensating fibers and FBG modules, using a 5 x 80 Gbit/s 100-GHz-spaced wavelength division multiplexing 4-ary DPSK signal. The results show that the FBG-based system provides a 2 dB higher optimal launch power, which leads to more than 3 dB optical signal-to-noise ratio (OSNR) improvement at the receiver. For systems with coherent detection, we evaluate the influence of GDR in a 112 Gbit/s dual-polarization quadrature phase shift keying system with respect to signal wavelength. In addition, we demonstrate that, at the optimal launch power, the 112 Gbit/s systems implementing FBG modules and that using electronic dispersion compensation provide similar performance after 840 km transmission despite the fact that the FBG-based system delivers lower OSNR at the receiver. Lastly, we quantify the GDR mitigation capability of a digital linear equalizer in the 112 Gbit/s coherent systems with respect to the equalizer tap number (N-tap). The results indicate that at least N-tap = 9 is required to confine Q-factor variation within 1 dB
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Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, October 1--December 31, 1996
The U.S. Department of Energy (DOE) has issued Public Service Company of Colorado (PSCo) a cost sharing contract to evaluate carbon-based sorbents for mercury control on a 600 acfm laboratory scale particulate control module (PCM). The PCM can simulate an electrostatic precipitator, a pulse-jet fabric filter, and a reverse air fabric filter and uses actual flue gas from an operating coal-fired power plant. Up to 3 different dry carbon-based sorbents will be tested to determine the mercury removal capability in the different configurations. The project is currently in the fifth quarter of an eight quarter Phase I project. The PCM has been fabricated and mercury removal testing with the ESP configuration has been completed. Original plans included the use on an on-line meercury analyzer to collect the test data. However, due to very low baseline mercury concentration, on-line measurement did not provide accurate data. The project has continued using a modified MESA method grab sample technique to determine inlet and outlet mercury concentrations. A major concern during sorbent evaluations has been the natural ability of the flyash at the test site to remove mercury. This has made determination of sorbent only mercury removal difficult. Overall vapor-phase mercury removals of 15 to 70% have been obtained but this includes mercury removals in the range of 30% by the flyash. It is believed that a maximum of approximately 40% removal due to the sorbent only has been obtained. A number of test and sampling modifications are in progress to increase the data confidence and many questions remain. Startup of the pulse jet configuration began in early November but results of this testing are not available at this time. The project team has decided to proceed with pulse jet testing using flue gas that does not contain significant flyash quantities to further investigate the sorbent only mercury removal
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Mirroring and switching authoritative personae: A ventriloquial analysis of shareholder engagement on carbon emissions
We examine how the authority of investors to speak about climate change with corporations is established. Leveraging the ‘communication as constitutive of organizations’ (CCO) perspective, we analyse who speaks on behalf of whom (or what) in shareholder engagement on corporate carbon emissions. Based on access to private dialogues between an engager acting on behalf of a pool of investors with twenty utility corporations, we identify how three authoritative personae—that of diplomat, advocate and coach—convey climate change concerns. We find that the mirroring of these authoritative personae by corporations may lead to deliberation, evasion, or rejection of the suggested courses of action. We theorise how relational authority is communicatively constituted in shareholder engagement through a process of mirroring and switching between authoritative personae. Our framework contributes to the study of CCO and relational authority by highlighting how meta-figures are used by external actors in an attempt to author appropriate corporate actions. We discuss the implications of our framework for the role of shareholder engagement in current attempts at greening financial capitalism
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