94 research outputs found
Climate robust culvert design: probabilistic estimates of fish passage impediments
*** This abstract is for a Snapshot (5-min) presentation. *** Many Washington State culverts are currently inadequate for fish passage. Apart from a few special cases, the standard for sizing culverts in Washington State is based on a simple linear function of bankfull width (BFW). This reflects a geomorphic approach to culvert design that can be applied across a large range of situations (Barnard et al. 2013, 2015). Future changes in BFW have previously been estimated by the Washington Department of Fish and Wildlife (WDFW) (Wilhere et al. 2016), by estimating the percent change in BFW derived from projected changes in runoff. This percent change can then be applied to direct observations of channel geometry. The main purpose of this talk is to present a novel new prototype for sizing culverts to account for the effects of climate change. The tool allows a user to enter some basic details about a culvert, choose a proposed design width, and evaluate the likelihood that it will fail to provide fish passage over a particular design lifetime. Likelihoods are estimated using a Monte Carlo approach, resulting in a probability distribution of future bankfull width. These probabilities will be used to assess the likelihood of culvert failure for different choices about how to size it. Since probabilities cannot be assigned to greenhouse gas scenarios, separate probabilities will be assessed for each greenhouse gas scenario, and likelihood estimates are produced for a given design lifetime. The talk will also include results from a recent evaluation of the climate and streamflow data used as the basis of the WDFW report. The work was funded by the Swinomish Indian Tribal Community (SITC) via the Skagit Climate Science Consortium (SC2)
Space matters: incorporating mechanistically determined spatial patterns into projected impacts of climate change on stream temperature
River temperatures are increasing as a results of climate change, and combined with decreased summertime flows, coldwater species are becoming increasingly stressed. In order to conserve sensitive species, managers need an estimate of how the availability of summertime thermal refuges in rivers will change in the future. Here, we applied the DHSVM-RBM, an existing process-based water temperature model that has been shown to accurately represent temporal variance in water temperature over hours to years. We calibrated this model to empirical data for two case study watersheds (Siletz River, Oregon and Snoqualmie River, Washington) to also ensure representation of observed spatial heterogeneity during summer. We used the model to predict future spatiotemporal patterns in water temperature that may arise as a result of climate change and to assess Pacific salmon vulnerability. We then compared our predictions to those made by statistical models to assess the unique benefits and constraints of a process-based approach. We found that a substantial decrease of snowmelt, and subsequently summer flow, will drive increases in water temperature and spatial variability in future summers. Our vulnerability analysis suggested that for salmon and steelhead exposed to warm August temperatures, conditions are already stressful in lower portions of the case study watersheds, and unlikely to become better in the future. All models predicted generally similar spatial patterns of water temperature in the future; across models, future cool patches will be reduced in number and located farther upstream. However, projected increases in water temperature were strikingly different among models, ranging from about +5 oC in the Snoqualmie River as predicted by DHSVM-RBM, to a negligible change in both watersheds as predicted by statistical methods. This information can be used to identify locations where protection and restoration of coolwater habitats may be most important into the future
Integrated floodplain management in Washington: How can we make it more resilient?
Floodplains are home to a wide range of economic, cultural, and natural resources. Although there is a strong desire to include climate change into these planning efforts, very little guidance has been developed to help incorporate climate impacts into planning and design. This is further complicated by weak or non-existent coordination among the various agencies, jurisdictions, and interests that have a stake in floodplain management. This talk will describe a recent assessment – from the perspective of agency-level flood risk managers – of ways to better integrate climate change in floodplain management. The work was focused on the Washington State Silver Jackets (WA SJ), an inter-agency group aimed at coordinating among flood risk management agencies: FEMA, Army Corps, USGS, National Weather Service, and the Washington State Departments of Ecology, Transportation, and the Emergency Management Division. Based on our findings, we developed a climate resilience and flood risk management workplan focused on the following five themes: (1) Improved projections of future flood impacts, (2) Resources to support local planners, (3) Improved coordination among agencies, scientists, and local floodplain managers, (4) Improved public engagement, and (5) Streamlined planning processes. Specific workplan actions were prioritized by the WA SJ team at a workshop in early June 2017, and the group is already taking action to fund and begin work on these priorities. Ultimately, the goal of this work is to widen the community of practice around climate-resilient integrated floodplain management through strengthened connections between agencies and locals, increased capacity, and improved technical resources for decision-makers
Projecting the Hydrologic Impacts of Climate Change on Montane Wetlands
Wetlands are globally important ecosystems that provide critical services for natural communities and human society. Montane wetland ecosystems are expected to be among the most sensitive to changing climate, as their persistence depends on factors directly influenced by climate (e.g. precipitation, snowpack, evaporation). Despite their importance and climate sensitivity, wetlands tend to be understudied due to a lack of tools and data relative to what is available for other ecosystem types. Here, we develop and demonstrate a new method for projecting climate-induced hydrologic changes in montane wetlands. Using observed wetland water levels and soil moisture simulated by the physically based Variable Infiltration Capacity (VIC) hydrologic model, we developed site-specific regression models relating soil moisture to observed wetland water levels to simulate the hydrologic behavior of four types of montane wetlands (ephemeral, intermediate, perennial, permanent wetlands) in the U. S. Pacific Northwest. The hybrid models captured observed wetland dynamics in many cases, though were less robust in others. We then used these models to a) hindcast historical wetland behavior in response to observed climate variability (1916–2010 or later) and classify wetland types, and b) project the impacts of climate change on montane wetlands using global climate model scenarios for the 2040s and 2080s (A1B emissions scenario). These future projections show that climate-induced changes to key driving variables (reduced snowpack, higher evapotranspiration, extended summer drought) will result in earlier and faster drawdown in Pacific Northwest montane wetlands, leading to systematic reductions in water levels, shortened wetland hydroperiods, and increased probability of drying. Intermediate hydroperiod wetlands are projected to experience the greatest changes. For the 2080s scenario, widespread conversion of intermediate wetlands to fast-drying ephemeral wetlands will likely reduce wetland habitat availability for many species
Effect of blood pressure and glycemic control on the plasma cell-free DNA in hemodialysis patients
AbstractBackgroundThe plasma levels of cell-free DNA (cfDNA) are known to be elevated under inflammatory or apoptotic conditions. Increased cfDNA levels have been reported in hemodialysis (HD) patients. The aim of this study was to investigate the clinical significance of cfDNA in HD patients.MethodsA total of 95 patients on HD were enrolled. We measured their predialysis cfDNA levels using real-time EIF2C1 gene sequence amplification and analyzed its association with certain clinical parameters.ResultsThe mean plasma cfDNA level in the HD patients was 3,884 ± 407 GE/mL, and the mean plasma cfDNA level in the control group was 1,420 ± 121 GE/mL (P < 0.05). Diabetic patients showed higher plasma cfDNA levels compared with nondiabetic patients (P < 0.01). Patients with cardiovascular complications also showed higher plasma cfDNA levels compared with those without cardiovascular complication (P < 0.05). In univariable analysis, the cfDNA level was associated with 3-month mean systolic blood pressure (SBP), white blood cell, serum albumin, creatinine (Cr), normalized protein catabolic rate in HD patients. In diabetic patients, it was significantly correlated with SBP, hemoglobin A1c, and serum albumin. In multivariate analysis, SBP was the independent determinant for the cfDNA level. In diabetic patients, cfDNA level was independently associated with hemoglobin A1c and SBP.ConclusionsIn patients with HD, cfDNA is elevated in diabetic patients and patients with cardiovascular diseases. Uncontrolled hypertension and poor glycemic control are independent determinants for the elevated cfDNA. Our data suggest that cfDNA might be a marker of vascular injury rather than proinflammatory condition in HD patients
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Comparing Large-Scale Hydrological Model Predictions with Observed Streamflow in the Pacific Northwest: Effects of Climate and Groundwater
Assessing uncertainties in hydrologic models can improve accuracy in predicting future streamflow. Here,
simulated streamflows using the Variable Infiltration Capacity (VIC) model at coarse (1/16°) and fine (1/120°)
spatial resolutions were evaluated against observed streamflows from 217 watersheds. In particular, the adequacy
of VIC simulations in groundwater- versus runoff-dominated watersheds using a range of flow metrics
relevant for water supply and aquatic habitat was examined. These flow metrics were 1) total annual
streamflow; 2) total fall, winter, spring, and summer season streamflows; and 3) 5th, 25th, 50th, 75th, and 95th
flow percentiles. The effect of climate on model performance was also evaluated by comparing the observed
and simulated streamflow sensitivities to temperature and precipitation. Model performance was evaluated
using four quantitative statistics: nonparametric rank correlation ρ, normalized Nash–Sutcliffe efficiency
NNSE, root-mean-square error RMSE, and percent bias PBIAS. The VIC model captured the sensitivity of
streamflow for temperature better than for precipitation and was in poor agreement with the corresponding
temperature and precipitation sensitivities derived from observed streamflow. The model was able to capture
the hydrologic behavior of the study watersheds with reasonable accuracy. Both total streamflow and flow
percentiles, however, are subject to strong systematic model bias. For example, summer streamflows were
underpredicted (PBIAS = -13%) in groundwater-dominated watersheds and overpredicted (PBIAS = 48%) in runoff-dominated watersheds. Similarly, the 5th flow percentile was underpredicted (PBIAS = -51%) in groundwater-dominated watersheds and overpredicted (PBIAS = 19%) in runoff-dominated
watersheds. These results provide a foundation for improving model parameterization and calibration in
ungauged basins.Keywords: Model errors, Hydrologic models, Model evaluation/performanc
Management of Complex Regional Pain Syndrome Type 1 With Total Spinal Block
Complex regional pain syndrome (CRPS) is a painful and disabling disorder that can affect one or more extremities. Unfortunately, the knowledge concerning its natural history and mechanism is very limited and many current rationales in treatment of CRPS are mainly dependent on efficacy originated in other common conditions of neuropathic pain. Therefore, in this study, we present a case using a total spinal block (TSB) for the refractory pain management of a 16-year-old male CRPS patient, who suffered from constant stabbing and squeezing pain, with severe touch allodynia in the left upper extremity following an operation of chondroblastoma. After the TSB, the patient's continuous and spontaneous pain became mild and the allodynia disappeared and maintained decreased for 1 month
Memory Impairment in Estrogen Receptor α Knockout Mice Through Accumulation of Amyloid-β Peptides
Impacts of Climate Change on Regulated Streamflow, Hydrologic Extremes, Hydropower Production, and Sediment Discharge in the Skagit River Basin
Monitoring and modeling riverine thermal regimes in a changing climate: implications for native and non-native fishes
Thermal landscapes include minute-to-minute fluctuations and meter-to-meter diversity; both of which are likely to shift with future changes in climate. We have designed a water temperature monitoring network on the Snoqualmie River with 40+ stations recording water temperature every 30-min and we now have 6 full years of data. Using spatial stream network models, these data are providing visualizations of how water temperatures fluctuate over time and space. By modeling facets of the thermal regime of importance to particular species and life-stages, we can map and estimate where and when suitable habitat conditions occur. Layering individual-based models of native and non-native species as well as forecasted future water temperature regimes, we can estimate how species of concern may respond to these future conditions. The record-breaking droughts and high temperatures in 2015 across the Pacific Northwest of the United States, USA also provide a window into what future thermal landscapes could look like. We observed drier and warmer conditions in 2015 as compared to what has been observed since 1960; however, patterns were neither consistent over the year nor on the network. Some sites showed dramatic increases in temperature while other sites displayed air and water temperature patterns that were not particularly different from typical years. We compared the distribution of thermally-suitable habitats in 2015 to that of previous, more typical years and conclude that if we observe years like 2015 more frequently in the future, we can expect shifts in the thermal landscape to be less favorable to native, cool-water fishes such as Chinook salmon and Bull trout while they benefit generalist non-native species such as large-mouth bass. Using the monitoring data collected so far, we can estimate where those changes are most likely to occur on the network
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