2,585 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)
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
A Spectral Line Survey from 138.3 to 150.7 GHZ toward Orion-KL
We present the results of a spectral line survey from 138.3 to 150.7 GHz
toward Orion-KL. The observations were made using the 14 m radio telescope of
Taeduk Radio Astronomy Observatory. Typical system temperatures were between
500 and 700 K, with the sensitivity between K in units of .
A total of 149 line spectra are detected in this survey. Fifty lines have
been previously reported, however we find 99 new detections. Among these new
lines, 32 are `unidentified', while 67 are from molecular transitions with
known identifications. There is no detection of H or He recombination lines.
The identified spectra are from a total of 16 molecular species and their
isotopic variants. In the range from 138.3 to 150.7 GHz, the strongest spectral
line is the J=3-2 transition of CS molecule, followed by transitions of the
, , , and . Spectral lines from
the large organic molecules such as , , , and are prominent; with 80 % of the
identified lines arising from transitions of these molecules. The rotational
temperatures and column densities are derived using the standard rotation
diagram analysis for (), , and with and . These estimates are fairly comparable to the values for the
same molecule in other frequency regions by other studies.Comment: 10 figures, 2 tex files for a manuscript and tables, accepted to Ap
Third-order exceptional point in an ion-cavity system
We investigate a scheme for observing the third-order exceptional point (EP3)
in an ion-cavity setting. In the lambda-type level configuration, the ion is
driven by a pump field, and the resonator is probed with another weak laser
field. We exploit the highly asymmetric branching ratio of an ion's excited
state to satisfy the weak-excitation limit, which allows us to construct the
non-Hermitian Hamiltonian . Via fitting the
cavity-transmission spectrum, the eigenvalues of are
obtained. The EP3 appears at a point where the Rabi frequency of the pump laser
and the atom-cavity coupling constant balance the loss rates of the system.
Feasible experimental parameters are provided.Comment: 9 pages, 6 figure
Association of Body Mass Index and Fracture Risk Varied by Affected Bones in Patients with Diabetes: A Nationwide Cohort Study
Background Body mass index (BMI) is a risk factor for the type 2 diabetes (T2DM), and T2DM accompanies various complications, such as fractures. We investigated the effects of BMI and T2DM on fracture risk and analyzed whether the association varied with fracture locations. Methods This study is a nationwide population-based cohort study that included all people with T2DM (n=2,746,078) who received the National Screening Program during 2009–2012. According to the anatomical location of the fracture, the incidence rate and hazard ratio (HR) were analyzed by dividing it into four categories: vertebra, hip, limbs, and total fracture. Results The total fracture had higher HR in the underweight group (HR, 1.268; 95% CI, 1.228 to 1.309) and lower HR in the obese group (HR, 0.891; 95% CI, 0.882 to 0.901) and the morbidly obese group (HR, 0.873; 95% CI, 0.857 to 0.89), compared to reference (normal BMI group). Similar trends were observed for HR of vertebra fracture. The risk of hip fracture was most prominent, the risk of hip fracture increased in the underweight group (HR, 1.896; 95% CI, 1.178 to 2.021) and decreased in the obesity (HR, 0.643; 95% CI, 0.624 to 0.663) and morbidly obesity group (HR, 0.627; 95% CI, 0.591 to 0.665). Lastly, fracture risk was least affected by BMI for limbs. Conclusion In T2DM patients, underweight tends to increase fracture risk, and overweight tends to lower fracture risk, but association between BMI and fracture risk varied depending on the affected bone lesions
High-resolution crystal structure of the non-specific lipid-transfer protein from maize seedlings
AbstractBackground: The movement of lipids between membranes is aided by lipid-transfer proteins (LTPs). Some LTPs exhibit broad specificity, transferring many classes of lipids, and are termed non-specific LTPs (ns-LTPs). Despite their apparently similar mode of action, no sequence homology exists between mammalian and plant ns-LTPs and no three-dimensional structure has been reported for any plant ns-LTP.Results We have determined the crystal structure of ns-LTP from maize seedlings by multiple isomorphous replacement and refined the structure to 1.9 å resolution. The protein comprises a single compact domain with four α-helices and a long C-terminal region. The eight conserved cysteines form four disulfide bridges (assigned as Cys4–Cys52, Cys14–Cys29, Cys30–Cys75, and Cys50–Cys89) resolving the ambiguity that remained from the chemical determination of pairings in the homologous protein from castor bean. Two of the bonds, Cys4–Cys52 and Cys50–Cys89, differ from what would have been predicted from sequence alignment with soybean hydrophobic protein. The complex between maize ns-LTP and hexadecanoate (palmitate) has also been crystallized and its structure refined to 1.8 å resolution.Conclusion The fold of maize ns-LTP places it in a new category of all-α-type structure, first described for soybean hydrophobic protein. In the absence of a bound ligand, the protein has a tunnel-like hydrophobic cavity, which is large enough to accommodate a long fatty acyl chain. In the structure of the complex with palmitate, most of the acyl chain is buried inside this hydrophobic cavity
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