Automation of DEM Cutting for Hydrologic/Hydraulic Modeling, TR-631, 2015

Hydrologic analysis is a critical part of transportation design because it helps ensure that hydraulic structures are able to accommodate the flow regimes they are likely to see. This analysis is currently conducted using computer simulations of water flow patterns, and continuing developments in elevation survey techniques result in higher and higher resolution surveys. Current survey techniques now resolve many natural and anthropogenic features that were not practical to map and, thus, require new methods for dealing with depressions and flow discontinuities. A method for depressional analysis is proposed that uses the fact that most anthropogenically constructed embankments are roughly more symmetrical with greater slopes than natural depressions. An enforcement method for draining depressions is then analyzed on those depressions that should be drained. This procedure has been evaluated on a small watershed in central Iowa, Walnut Creek of the South Skunk River, HUC12 # 070801050901, and was found to accurately identify 88 of 92 drained depressions and place enforcements within two pixels, although the method often tries to drain prairie pothole depressions that are bisected by anthropogenic features.

Scale Effects in Hydraulic Model Tests of Rock Protected Structures, HR-119, 1970

A laboratory investigation was undertaken to determine the limiting model Reynolds number above which the scour behavior of rock protected structures can be reproduced in hydraulic models scaled according to the Froude criterion. A submerged jet was passed over an initially full scour pocket containing uniform glass spheres and the rate of scour was measured as a function of time. The dimensions of the scour pocket and jet and the particle diameters were varied as needed to maintain strict geometric similarity. For each of two different Froude numbers the Reynolds number was varied over a wide range. The normalized scour rate was found to be practically independent of the Reynolds number, R, (based on the jet velocity and particle diameter) at values of R above about 2.5 x 10^3, and to decrease with Rat smaller values. A grid placed in the jet was found to have a very strong effect on the scour rate. In an attempt to explain the effect of R on the scour behavior, turbulent pressure and velocity fluctuations were measured in air flows and water flows, respectively, over rigid scour pockets having the same geometry as those formed in the scour experiments. The normalized spectra of the fluctuations were found to be nearly independent of R, but the flow pattern was found to be very sensitive to the inlet condition, the jet deflecting upward or downward in a not wholly explainable manner. This indicates that scour behavior can be modeled only if the approach flow is also accurately modeled.

A non-linear Bayesian approach for upscaling local-scale hydraulic conductivity measurements based on local- and regional-scale geophysical data

Significant progress has been made with regard to the quantitative integration of geophysical and hydrological data at the local scale. However, extending the corresponding approaches to the regional scale represents a major, and as-of-yet largely unresolved, challenge. To address this problem, we have developed an upscaling procedure based on a Bayesian sequential simulation approach. This method is then applied to the stochastic integration of low-resolution, regional-scale electrical resistivity tomography (ERT) data in combination with high-resolution, local-scale downhole measurements of the hydraulic and electrical conductivities. Finally, the overall viability of this upscaling approach is tested and verified by performing and comparing flow and transport simulation through the original and the upscaled hydraulic conductivity fields. Our results indicate that the proposed procedure does indeed allow for obtaining remarkably faithful estimates of the regional-scale hydraulic conductivity structure and correspondingly reliable predictions of the transport characteristics over relatively long distances.

On-pump fibrillating heart mitral valve replacement with the SAPIEN? XT transcatheter heart valve.

In some high-risk patients, standard mitral valve replacement can represent a challenging procedure, requiring a risky extensive decalcification of the annulus. In particular, high-risk redo patients and patients with a previously implanted transcatheter aortic valve, who develop calcific mitral disease, would benefit from the development of new, minimally invasive, transcatheter or hybrid techniques for mitral valve replacement. In particular, mixing transcatheter valve therapies and well-established minimally invasive techniques for mitral replacement or repair can help in decreasing the surgical risk and the technical complexity. Thus, placing transcatheter, balloon-expandable Sapien? XT stent-valves in calcified, degenerated mitral valves through a right thoracotomy, a left atriotomy and on an on-pump fibrillating heart, represents an attractive alternative to standard surgery in redo patients, in patients with concomitant transcatheter aortic stent-valves in place and in patients with a high-risk profile. We describe this hybrid technique in detail.

Hydraulic Cement Grout Testing, MLR-89-14, 1990

Currently, hydraulic cement grouts are approved for Iowa Department of Transportation projects on the basis of a pullout test. However, other properties of the grouts should be evaluated. Therefore, this research was initiated to develop criteria to better evaluate hydraulic cement grouts. Fourteen grouts were tested for compressive strength, time of set, durability, consistency and shrinkage. Tested grouts all yielded compressive strengths higher than 3000 psi at 7 days and durability factors were well above 70. Time of set and consistency was adequate. The testing showed most grouts tested shrank, even though tested grouts were labeled non-shrink grouts. For many applications of grouts such as setting in anchor bolts and as a filler, minor shrinkage is not a problem. However, for some critical applications, shrinkage cannot be tolerated. The proposed Instructional Memorandum will identify those grouts which do not excessively shrink or expand in the tests used. Based on test results, criteria for evaluation of hydraulic cement grouts have been recommended. Evaluation consists of tests for compressive strength, time of set, durability, consistency, shrinkage and pullout test.

Stochastic inversion of tracer test and electrical geophysical data to estimate hydraulic conductivities.

Quantifying the spatial configuration of hydraulic conductivity (K) in heterogeneous geological environments is essential for accurate predictions of contaminant transport, but is difficult because of the inherent limitations in resolution and coverage associated with traditional hydrological measurements. To address this issue, we consider crosshole and surface-based electrical resistivity geophysical measurements, collected in time during a saline tracer experiment. We use a Bayesian Markov-chain-Monte-Carlo (McMC) methodology to jointly invert the dynamic resistivity data, together with borehole tracer concentration data, to generate multiple posterior realizations of K that are consistent with all available information. We do this within a coupled inversion framework, whereby the geophysical and hydrological forward models are linked through an uncertain relationship between electrical resistivity and concentration. To minimize computational expense, a facies-based subsurface parameterization is developed. The Bayesian-McMC methodology allows us to explore the potential benefits of including the geophysical data into the inverse problem by examining their effect on our ability to identify fast flowpaths in the subsurface, and their impact on hydrological prediction uncertainty. Using a complex, geostatistically generated, two-dimensional numerical example representative of a fluvial environment, we demonstrate that flow model calibration is improved and prediction error is decreased when the electrical resistivity data are included. The worth of the geophysical data is found to be greatest for long spatial correlation lengths of subsurface heterogeneity with respect to wellbore separation, where flow and transport are largely controlled by highly connected flowpaths.

FXYD Proteins Reverse Inhibition of the Na+-K+ Pump Mediated by Glutathionylation of Its {beta}1 Subunit.

The seven members of the FXYD protein family associate with the Na(+)-K(+) pump and modulate its activity. We investigated whether conserved cysteines in FXYD proteins are susceptible to glutathionylation and whether such reactivity affects Na(+)-K(+) pump function in cardiac myocytes and Xenopus oocytes. Glutathionylation was detected by immunoblotting streptavidin precipitate from biotin-GSH loaded cells or by a GSH antibody. Incubation of myocytes with recombinant FXYD proteins resulted in competitive displacement of native FXYD1. Myocyte and Xenopus oocyte pump currents were measured with whole-cell and two-electrode voltage clamp techniques, respectively. Native FXYD1 in myocytes and FXYD1 expressed in oocytes were susceptible to glutathionylation. Mutagenesis identified the specific cysteine in the cytoplasmic terminal that was reactive. Its reactivity was dependent on flanking basic amino acids. We have reported that Na(+)-K(+) pump β(1) subunit glutathionylation induced by oxidative signals causes pump inhibition in a previous study. In the present study, we found that β(1) subunit glutathionylation and pump inhibition could be reversed by exposing myocytes to exogenous wild-type FXYD3. A cysteine-free FXYD3 derivative had no effect. Similar results were obtained with wild-type and mutant FXYD proteins expressed in oocytes. Glutathionylation of the β(1) subunit was increased in myocardium from FXYD1(-/-) mice. In conclusion, there is a dependence of Na(+)-K(+) pump regulation on reactivity of two specifically identified cysteines on separate components of the multimeric Na(+)-K(+) pump complex. By facilitating deglutathionylation of the β(1) subunit, FXYD proteins reverse oxidative inhibition of the Na(+)-K(+) pump and play a dynamic role in its regulation.

Predictors of mortality from pump failure and sudden cardiac death in patients with systolic heart failure and left ventricular dyssynchrony: results of the CARE-HF trial.

BACKGROUND: Determining a specific death cause may facilitate individualized therapy in patients with heart failure (HF). Cardiac resynchronization therapy (CRT) decreased mortality in the Cardiac Resynchronization in Heart Failure trial by reducing pump failure and sudden cardiac death (SCD). This study analyzes predictors of specific causes of death. METHODS AND RESULTS: Univariate and multivariate analyses used 8 baseline and 3-month post-randomization variables to predict pump failure and SCD (categorized as "definite," "probable," and "possible"). Of 255 deaths, 197 were cardiovascular. There were 71 SCDs with a risk reduction by CRT of 0.47 (95% confidence interval 0.29-0.76; P = .002) with similar reductions in SCD classified as definite, probable, and possible. Univariate SCD predictors were 3-month HF status (mitral regurgitation [MR] severity, plasma brain natriuretic peptide [BNP], end-diastolic volume, and systolic blood pressure), whereas randomization to CRT decreased risk. Multivariate SCD predictors were randomization to CRT 0.56 (0.53-0.96, P = .035) and 3-month MR severity 1.82 (1.77-2.60, P = .0012). Univariate pump failure death predictors related to baseline HF state (quality of life score, interventricular mechanical delay, end-diastolic volume, plasma BNP, MR severity, and systolic pressure), whereas randomization to CRT and nonischemic cardiomyopathy decreased risk; multivariate predictors of pump failure death were baseline plasma BNP and systolic pressure and randomization to CRT. CONCLUSION: CRT decreased SCD in patients with systolic HF and ventricular dyssynchrony. SCD risk was increased with increased severity of MR (including the 3-month value for MR as a time-dependent covariate) and reduced by randomization to CRT. HF death was increased related to the level of systolic blood pressure, log BNP, and randomization to CRT. These results emphasize the importance and interdependence of HF severity to mortality from pump failure and SCD.

Eosinophilic oesophagitis and proton pump inhibitor-responsive oesophageal eosinophilia have similar clinical, endoscopic and histological findings.

BACKGROUND: Some patients with a phenotypic appearance of eosinophilic oesophagitis (EoE) respond histologically to PPI, and are described as having PPI-responsive oesophageal eosinophilia (PPI-REE). It is unclear if PPI-REE is a GERD-related phenomenon, a subtype of EoE, or a completely unique entity. AIM: To compare demographic, clinical and histological features of EoE and PPI-REE. METHODS: Two databases were reviewed from the Walter Reed and Swiss EoE databases. Patients were stratified into two groups, EoE and PPI-REE, based on recent EoE consensus guidelines. Response to PPI was defined as achieving less than 15 eos/hpf and a 50% decrease from baseline following at least a 6-week course of treatment. RESULTS: One hundred and three patients were identified (63 EoE and 40 PPI-REE; mean age 40.2 years, 75% male and 89% Caucasian). The two cohorts had similar dysphagia (97% vs. 100%, P = 0.520), food impaction (43% vs. 35%, P = 0.536), and heartburn (33% vs. 32%, P = 1.000) and a similar duration of symptoms (6.0 years vs. 5.8 years, P = 0.850). Endoscopic features were also similar between EoE and PPI-REE; rings (68% vs. 68%, P = 1.000), furrows (70% vs. 70%, P = 1.000), plaques (19% vs. 10%, P = 0.272), strictures (49% vs. 30%, P = 0.066). EoE and PPI-REE were similar in the number of proximal (39 eos/hpf vs. 38 eos/hpf, P = 0.919) and distal eosinophils (50 vs. 43 eos/hpf, P = 0.285). CONCLUSIONS: EoE and PPI-responsive oesophageal eosinophilia are similar in clinical, histological and endoscopic features and therefore are indistinguishable without a PPI trial. Further studies are needed to determine why a subset of patients with oesophageal eosinophilia respond to PPI.

DFMA- Analysis and Aspects of Applying Internet Based Collaborative Design for Axial Eccentric Oil-Pump Design

The integrated system of design for manufacturing and assembly (DFMA) and internet based collaborative design are presented to support product design, manufacturing process, and assembly planning for axial eccentric oil-pump design. The presented system manages and schedules group oriented collaborative activities. The design guidelines of internet based collaborative design & DFMA are expressed. The components and the manufacturing stages of axial eccentric oil-pump are expressed in detail. The file formats of the presented system include the data types of collaborative design of the product, assembly design, assembly planning and assembly system design. Product design and assembly planning can be operated synchronously and intelligently and they are integrated under the condition of internet based collaborative design and DFMA. The technologies of collaborative modelling, collaborative manufacturing, and internet based collaborative assembly for the specific pump construction are developed. A seven-security level is presented to ensure the security of the internet based collaborative design system.

Experimental thermal hydraulic studies on the enhancement of safety of LWRs

The safe use of nuclear power plants (NPPs) requires a deep understanding of the functioning of physical processes and systems involved. Studies on thermal hydraulics have been carried out in various separate effects and integral test facilities at Lappeenranta University of Technology (LUT) either to ensure the functioning of safety systems of light water reactors (LWR) or to produce validation data for the computer codes used in safety analyses of NPPs. Several examples of safety studies on thermal hydraulics of the nuclear power plants are discussed. Studies are related to the physical phenomena existing in different processes in NPPs, such as rewetting of the fuel rods, emergency core cooling (ECC), natural circulation, small break loss-of-coolant accidents (SBLOCA), non-condensable gas release and transport, and passive safety systems. Studies on both VVER and advanced light water reactor (ALWR) systems are included. The set of cases include separate effects tests for understanding and modeling a single physical phenomenon, separate effects tests to study the behavior of a NPP component or a single system, and integral tests to study the behavior of the whole system. In the studies following steps can be found, not necessarily in the same study. Experimental studies as such have provided solutions to existing design problems. Experimental data have been created to validate a single model in a computer code. Validated models are used in various transient analyses of scaled facilities or NPPs. Integral test data are used to validate the computer codes as whole, to see how the implemented models work together in a code. In the final stage test results from the facilities are transferred to the NPP scale using computer codes. Some of the experiments have confirmed the expected behavior of the system or procedure to be studied; in some experiments there have been certain unexpected phenomena that have caused changes to the original design to avoid the recognized problems. This is the main motivation for experimental studies on thermal hydraulics of the NPP safety systems. Naturally the behavior of the new system designs have to be checked with experiments, but also the existing designs, if they are applied in the conditions that differ from what they were originally designed for. New procedures for existing reactors and new safety related systems have been developed for new nuclear power plant concepts. New experiments have been continuously needed.

Modeling of Pressurizer Using APROS and TRACE Thermal Hydraulic Codes

Diplomityön tavoitteena on paineistimen yksityiskohtainen mallintaminen APROS- ja TRACE- termohydrauliikkaohjelmistoja käyttäen. Rakennetut paineistinmallit testattiin vertaamalla laskentatuloksia paineistimen täyttymistä, tyhjentymistä ja ruiskutusta käsittelevistä erilliskokeista saatuun mittausdataan. Tutkimuksen päätavoitteena on APROSin paineistinmallin validoiminen käyttäen vertailuaineistona PACTEL ATWS-koesarjan sopivia paineistinkokeita sekä MIT Pressurizer- ja Neptunus- erilliskokeita. Lisäksi rakennettiin malli Loviisan ydinvoimalaitoksen paineistimesta, jota käytettiin turbiinitrippitransientin simulointiin tarkoituksena selvittää mahdolliset voimalaitoksen ja koelaitteistojen mittakaavaerosta johtuvat vaikutukset APROSin paineistinlaskentaan. Kokeiden simuloinnissa testattiin erilaisia noodituksia ja mallinnusvaihtoehtoja, kuten entalpian ensimmäisen ja toisen kertaluvun diskretisointia, ja APROSin sekä TRACEn antamia tuloksia vertailtiin kattavasti toisiinsa. APROSin paineistinmallin lämmönsiirtokorrelaatioissa havaittiin merkittävä puute ja laskentatuloksiin saatiin huomattava parannus ottamalla käyttöön uusi seinämälauhtumismalli. Työssä tehdyt TRACE-simulaatiot ovat osa United States Nuclear Regulatory Commissionin kansainvälistä CAMP-koodinkehitys-ja validointiohjelmaa.

Evolution of the epithelial sodium channel and the sodium pump as limiting factors of aldosterone action on sodium transport.

Despite large changes in salt intake, the mammalian kidney is able to maintain the extracellular sodium concentration and osmolarity within very narrow margins, thereby controlling blood volume and blood pressure. In the aldosterone-sensitive distal nephron (ASDN), aldosterone tightly controls the activities of epithelial sodium channel (ENaC) and Na,K-ATPase, the two limiting factors in establishing transepithelial sodium transport. It has been proposed that the ENaC/degenerin gene family is restricted to Metazoans, whereas the α- and β-subunits of Na,K-ATPase have homologous genes in prokaryotes. This raises the question of the emergence of osmolarity control. By exploring recent genomic data of diverse organisms, we found that: 1) ENaC/degenerin exists in all of the Metazoans screened, including nonbilaterians and, by extension, was already present in ancestors of Metazoa; 2) ENaC/degenerin is also present in Naegleria gruberi, an eukaryotic microbe, consistent with either a vertical inheritance from the last common ancestor of Eukaryotes or a lateral transfer between Naegleria and Metazoan ancestors; and 3) The Na,K-ATPase β-subunit is restricted to Holozoa, the taxon that includes animals and their closest single-cell relatives. Since the β-subunit of Na,K-ATPase plays a key role in targeting the α-subunit to the plasma membrane and has an additional function in the formation of cell junctions, we propose that the emergence of Na,K-ATPase, together with ENaC/degenerin, is linked to the development of multicellularity in the Metazoan kingdom. The establishment of multicellularity and the associated extracellular compartment ("internal milieu") precedes the emergence of other key elements of the aldosterone signaling pathway.

How to Improve the Use of Proton Pump Inhibitors

Introduction: Proton pump inhibitors (PPI) are one of the most prescribed medications in the world with proven efficacy. However, several studies showed that their use often doesn't respect indications, leading to over-consumption, thus exposing patients to drug interactions and adverse events (for example pneumonias). Interruption of PPIs can induce a rebound phenomenon. This generates costs for health systems.Methods: This is a prospective interventional study performed in two hospitals: La Chaux-de-Fonds (CDF, cases) and Neucha^tel (NE, control) during two six-month periods, comparing use of PPIs before and after intervention. We elaborated recommendations (PPI doses and treatment duration) based on recent medical literature that we summarized on A6 cards and gave out to all prescribing doctors in the hospital of CDF and held a 30-minute information session for the departments of surgery, medicine and anesthesiology in March 2010. Doctors were asked to apply our recommendations as often as possible, leaving space for their own assessment. No information was given to the doctors of the control hospital. The number of PPI tablets that the pharmacy sent to each careunit in both hospitals was counted and adjusted to the number of patientdays from April to September 2009 (before intervention) and April to September 2010 (after intervention). The number of other antacids that were used in both hospitals was counted during the same periods. General practitioners (GP) in the region around CDF received an explanation letter to avoid re-introduction, after discharge from the hospital, of PPI treatment stopped during the stay. The number of gastro-duodenal ulcers and upper digestive hemorrhages was counted from April to December 2009 and the same period in 2010 in both hospitals.Results: In 2010, in the hospital of CDF, the use of PPIs per 100 patient-days decreased by 36% in the surgical and medical departments compared to 2009. In the control hospital the use of PPIs per 100 patient-days increased by 10% in the surgical department and decreased by 5% in the medical department during the same periods. The decrease from 2009 to 2010 of PPI utilization in CDF comparing to NE is statistically significant: p<0.0001. Use of other antacids didn't change, ulcers or digestive hemorrhages decreased slightly from 2009 to 2010 in both hospitals. Conclusions: The study showed that with a very low-cost intervention, it is possible to decrease considerably the use of PPIs in a hospital, without taking any risk for gastro-intestinal complications.