bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spanwise Cylinder Wake Hydrodynamics and Fish Behavior
Authors: Muhawenimana V. , Wilson C. A. M. E. , Ouro P. , Cable J. 
Published: October 2019

AbstractFlows generated near hydro‐engineering structures are characterized by energetic three‐dimensional flow structures that are markedly different from naturally occurring fish habitats. The current study evaluated the interaction of Nile tilapia (Oreochromis niloticus) with spanwise rollers in the turbulent wake of a cylinder in both the wake bubble and the vortex shedding further downstream. The flow field hydrodynamics were measured using an acoustic Doppler velocimeter for Reynolds number (ReD) regimes ranging from 3,730 to 33,590, over a streamwise length of six diameters downstream of the cylinder, and revealed a pair of alternating vortices rotating about a spanwise axis, which were rendered asymmetric by the bed boundary proximity. Fish avoided areas where vorticity, turbulence intensity, turbulent kinetic energy, eddy size, and Reynolds shear stress were highest. Events of stability loss, referred to as spills, were significantly correlated to the turbulence integral length scale relative to fish standard length, with the peak number of spills occurring when the eddy length approached 45% to 50% of the fish length. Spill events significantly depended on ReD, Reynolds stress, and vorticity and varied according to fish length and weight. Among zones of similar Reynolds stress and vorticity magnitude, spills were most frequent when Reynolds shear stress was positive, downward acting and eddies rotated clockwise, which highlights the importance of direction and orientation of flow structures in determining the hydrodynamic forces that affect fish swimming stability. Recommendations are made for the inclusion of these metrics in the design and refinement of hydro‐engineering schemes.
Physical Controls on Salmon Redd Site Selection in Restored Reaches of a Regulated, Gravel‐Bed River
Authors: Harrison Lee R. , Bray Erin , Overstreet Brandon , Legleiter Carl J. , Brown Rocko A. , Merz Joseph E. , Bond Rosealea M. , Nicol Colin L. , Dunne Thomas 
Published: October 2019

AbstractLarge‐scale river restoration programs have emerged recently as a tool for improving spawning habitat for native salmonids in highly altered river ecosystems. Few studies have quantified the extent to which restored habitat is utilized by salmonids, which habitat features influence redd site selection, or the persistence of restored habitat over time. We investigated fall‐run Chinook salmon spawning site utilization and measured and modeled corresponding habitat characteristics in two restored reaches: a reach of channel and floodplain enhancement completed in 2013 and a reconfigured channel and floodplain constructed in 2002. Redd surveys demonstrated that both restoration projects supported a high density of salmon redds, 3 and 14 years following restoration. Salmon redds were constructed in coarse gravel substrates located in areas of high sediment mobility, as determined by measurements of gravel friction angles and a grain entrainment model. Salmon redds were located near transitions between pool‐riffle bedforms in regions of high predicted hyporheic flows. Habitat quality (quantified as a function of stream hydraulics) and hyporheic flow were both strong predictors of redd occurrence, though the relative roles of these variables differed between sites. Our findings indicate that physical controls on redd site selection in restored channels were similar to those reported for natural channels elsewhere. Our results further highlight that in addition to traditional habitat criteria (e.g., water depth, velocity, and substrate size), quantifying sediment texture and mobility, as well as intragravel flow, provides a more complete understanding of the ecological benefits provided by river restoration projects.
Near‐Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion
Authors: Beeler N. M. , McLaskey Gregory C. , Lockner David , Kilgore Brian 
Published: October 2019

AbstractWe compared near‐fault velocity spectra recorded during laboratory experiments to that of natural earthquakes. We fractured crystalline rock samples at room temperature and intermediate confining pressure (50 MPa). Subsequent slip events were generated on the fracture surfaces under higher confinement (300 MPa). Velocity spectra from rock fracture resemble the inverse frequency (1/f) decay of natural earthquake velocity. This spectrum can be attributed to fault creation via seismic fracturing over a wide range of spatial scales. In contrast, subsequent slips on the rough fracture surfaces are depleted in high frequency energy and falloff approximately as 1/f2. The 1/f2 spectrum is more consistent with a slider‐block model obeying static‐kinetic friction than a natural earthquake. The depleted high frequency content precludes the rough fault experiments from being directly analogous to natural sources. The suppression of high frequencies may have resulted from two possible factors: (1) the presence of a well‐developed shear zone and coseismic damping of the fault motion by dissipation within it or, in our favored interpretation, (2) a smaller amount of energy dissipated by shearing relative to the total energy release at elevated confining pressure. In context of the latter explanation, a unifying concept that applies to these experiments, earthquakes, ground motion, and models of complex radiated motion is that high frequency radiated energy is relatively enhanced when total energy release is nearly balanced within the source region by dissipative processes. This near‐critical energy release condition can be accessed at low normal stress in laboratory experiments.
Polarimetric Radar Convective Cell Tracking Reveals Large Sensitivity of Cloud Precipitation and Electrification Properties to CCN
Authors: Hu Jiaxi , Rosenfeld Daniel , Ryzhkov Alexander , Zrnic Dusan , Williams Earle , Zhang Pengfei , Snyder Jeffrey C. , Zhang Renyi , Weitz Richard 
Published: October 2019

AbstractHypotheses have been proposed for decades about the effect of activated cloud condensation nuclei (CCN) on delaying the warm rain process, invigorating deep convective cloud vertical development, and enhancing mixed‐phase processes. Observational support has been only qualitative with mixed results due to the lack of regional measurements of CCN concentration (NCCN), while simulations have not produced a robust consensus. Quantitative assessments of these relationships became possible with the advent of NCCN retrievals from satellites; when combined with measurements by polarimetric radar and Lightning Mapping Array (LMA), tracking convective cells observed on radar and examining precipitation properties throughout the cells' life cycle has permitted the study of the impact of NCCN on cloud and precipitation characteristics. We composited more than 2,800 well‐tracked cells in the Houston region and stratified them by NCCN, convective available potential energy (CAPE), and urban/rural locations. The results show that increased NCCN invigorates the convection until saturation near NCCN = 1,000 cm3; increasing NCCN from ~400 to an optimum of ~1,000 cm3 increases lightning activity by an order of magnitude. A further increase in CCN decreases lightning rates. Adding CAPE enhances lightning only under low NCCN (e.g., less than 500 cm3). The presence of the urban area enhances lightning for similar NCCN concentrations, although this applies mainly under low NCCN conditions. The urban heat island as manifested by cloud base height cannot explain this observation. It is suspected that the urban ultrafine aerosols contribute to the storm electrification.
Modeling Soil Wind Erosion From Agroecological Classes of the Pacific Northwest in Response to Current Climate
Authors: Pi Huawei , Huggins David R. , Abatzoglou John T. , Sharratt Brenton 
Published: October 2019

AbstractSoil wind erosion is a major concern of the agricultural community in the inland Pacific Northwest (iPNW) United States. This study quantitatively predicts dust emissions from agroecological classes (AECs) of iPNW based on soil and land use types in response to climate change. The Wind Erosion Prediction System (WEPS) was used to simulate daily soil and PM10 (particulate matter ≤10 μm in aerodynamic diameter) loss at 29 meteorological stations across the iPNW. From 2009 to 2018, annual soil and PM10 loss decreased 1.18 and 0.05 kg m−2 yr−1, respectively. We presume that this decrease may be due to decreased wind speed, rather than other parameters like precipitation or solar radiation. St. John, WA had not only the highest annual soil loss but also the greatest mean wind speed and number of events with wind speeds >8 m/s. However, Lind, WA appeared to have greater soil surface erodibility in terms of greater rates of hourly soil and PM10 loss. Wind erosion occurred most frequently during March and April. The average maximum annual soil and PM10 loss in the grain‐fallow stable (24.7 and 0.63 kg/m2, respectively) exceeded that of all other agroecosystems. This suggested that maintaining crop cover is critical for protecting the soil surface from erosion.
Experimental Validation of the Near‐Bed Particle‐Borne Stress Profile in Aeolian Transport Systems
Authors: O'Brien Patrick , McKenna Neuman Cheryl 
Published: October 2019

AbstractSelf‐regulation of sediment transport by wind is widely assumed to derive from the partitioning of momentum from the fluid flow to the particle cloud. Consequently, the fluid stress on the bed surface is suggested by some to drop below that required to entrain particles, while the cloud is sustained by particle ricochet and splash that derive from the impacts of particles moving ballistically along the bed surface. While these theoretical constructs underpin present‐day numerical models of aeolian saltation, the particle‐borne stress has never been measured directly in either a laboratory or field setting. Such measurements are required for model validation and calibration of numerical simulations and were undertaken in vertical profile in the Trent Environmental Wind Tunnel using particle tracking velocimetry. Test sand was normally distributed with a median diameter of 590 μm. Particle momentum was calculated from the diameter and velocity of each image pair captured using high‐speed photography and then summed within each elevation band. The median diameter of the air‐borne particles was found to increase with friction velocity (u*), suggestive of sorting of the bed surface, and to decrease with elevation. Within a two‐dimensional framework, the vertical and windward components of the particle velocity were found to increase with elevation, with u* having little to no influence. Confirming the results of previous numerical simulations, these experiments show that the normalized particle‐borne stress increases exponentially toward the bed surface; however, within the lowest few millimeters where particle splash dominates, no consistent change is observed with elevation.
K‐Ar Dating of Fossil Seismogenic Thrusts in the Shimanto Accretionary Complex, Southwest Japan
Authors: Fisher Donald M. , Tonai Satoshi , Hashimoto Yoshitaka , Tomioka Naotaka , Oakley David 
Published: October 2019

AbstractK‐Ar ages of clay‐sized mineral grains are used to determine the timing of activity on fossil seismogenic faults within the Cretaceous‐Paleogene Shimanto accretionary complex, southwest Japan. Samples were collected from three regional faults that separate hanging wall coherent rocks from footwall subduction mélange: the Goshikinohama Fault that caps the Yokonami mélange, the roof thrust of the Okitsu mélange, and the Nobeoka Thrust that caps the Hyuga mélange. The K‐Ar ages of fault rocks decrease with decreasing 2M1 illite polytype component, indicating a mixture of 1Md and 2M1 illite polytypes. Based on illite dating analysis, the extrapolated ages of the pure 2M1 illite polytype from the Goshikinohama Fault, the roof thrust of the Okitsu mélange, and the Nobeoka Thrust are 79.3 ± 5.0, 66.1 ± 8.1, and 46.7 ± 8.2 Ma, respectively, similar to the depositional age of each host rock. Lower intercepts of regression lines, which correspond to samples containing 100% authigenic illite, are calculated as 50.7 ± 1.4, 18.4 ± 1.2, and 24.4 ± 1.4 Ma, respectively. These ages are significantly younger than both the depositional ages and the timing of accretion. These results indicate that authigenic illite associated with fault slip is not related to underthrusting along the subduction interface but rather formed during out‐of‐sequence thrusting in the upper plate. Early Miocene slip along faults of the northern Shimanto belt is coincident with major tectonic events along the convergent margin, including collision with elements of the Izu‐Bonin volcanic arc‐backarc system, and opening of the Japan Sea.
Evolutionary Cooperation in Transboundary River Basins
Authors: Yu Yang , Tang Pingzhong , Zhao Jianshi , Liu Bo , Mclaughlin Dennis 
Published: October 2019

AbstractCooperation in transboundary river basins can make water resources systems more efficient and benefit riparian stakeholders. However, in a basin with upstream and downstream stakeholders that have different interests, noncooperative outcomes have often been observed. These can be described by a one‐shot prisoners' dilemma game where noncooperation (defection) is a dominant equilibrium strategy. However, cooperative outcomes have also been observed in several transboundary settings, such as the Lancang‐Mekong River Basin in Asia. Such cooperation motivates our research effort to refine relevant game theoretic descriptions to account for the evolution of players' behaviors, from conflict to cooperation. In this study, a repeated game model is proposed to analyze evolutionary transboundary cooperation. A generalized evolutionary cooperation pattern with four stages is summarized, starting with noncooperation and ending with in‐depth cooperation. The Lancang‐Mekong River Basin and three other typical transboundary river management case studies are chosen to validate our theoretical findings. Upstream and downstream stakeholder behaviors are analyzed for these case studies, in accordance with a game payoff matrix that accounts for incentives to cooperate. The results indicate that patience and incremental benefits can lead stakeholders to adopt a cooperative equilibrium strategy if appropriate institutional mechanisms are in place. Such mechanisms can be developed through negotiations that recognize the wide range of stakeholder interests that may influence the decision to cooperate. Our analysis suggests that game theory can provide useful insights into the conditions and institutional mechanisms that foster cooperative strategies for managing transboundary water resources.
Comparison of AC breakdown characteristics on insulation paper (pressboard) immersed by three‐element mixed insulation oil and mineral oil
Authors: Feng Dawei , Hao Jian , Yang Lijun , Liao Ruijin , Chen Xin , Li Jian 
Published: October 2019

Insulation oil is an important dielectric in power devices, and many studies on mixed insulation oil have been conducted in recent years to improve the performance of insulation oils. To replace mineral oil directly, the authors previously developed a novel three‐element mixed insulation oil successfully; the main parameters of which satisfy the IEC 60296‐2012 standard for mineral oil. In the present study, the AC breakdown properties of insulation paper (pressboard) immersed by the new mixed oil and naphthenic mineral oil were compared. For both insulation oils, the increase in temperature cannot significantly reduce the breakdown strength of oil‐immersed insulation paper (pressboard) at a low moisture content, and the increment of moisture content cannot reduce the breakdown voltage at a low temperature (25°C). The breakdown voltage decreases only when the two factors increase simultaneously. For the mixed and mineral oils, the AC breakdown voltage of oil‐immersed paper (pressboard) with different thicknesses has significant difference. The mineral oil has a high breakdown voltage for the thin insulation paper, whereas the mixed oil has a high breakdown voltage when the thickness of the insulation paper (pressboard) exceeds 0.2 mm. This phenomenon is mainly caused by the breakdown field strength that varies with the increase of dielectric thickness and the different change trends of paper (pressboard) immersed with the mixed and the mineral oils. Moreover, the stack of thin multilayer insulation paper enables the mixed oil‐immersed paper to have a higher breakdown strength than the mineral oil‐immersed paper. For the AC breakdown voltage of oil‐immersed pressboard with an oil‐gap structure, the mixed oil is comprehensively superior to the mineral oil due to its larger relative permittivity.
Diagnostic Performance and Reliability of Non-Enhanced Imaging Characterization Quotients for the Differentiation of Infectious and Malignant Pulmonary Nodules in Hematological Patients Using 3T MRI
Authors: Nagel Sebastian Niko , Kim Damon , Wylutzki Tatjana , Steffen Ingo G. , Schwartz Stefan , Penzkofer Tobias , Hamm Bernd , Elgeti Thomas 
Published: October 2019

Purpose To evaluate the diagnostic performance and reliability of non-enhanced imaging characterization quotients (NICQs) derived from magnetic resonance imaging (MRI) in the differential diagnosis of pulmonary nodules in hematological patients.
Materials and Methods A total of 83 lesions in 45 consecutive hematological patients were analyzed (10 bacterial pneumonias, 16 fungal pneumonias, 19 pulmonary lymphoma manifestations). The MRI protocol included T2-weighted single-shot fast spin echo (FSE) and T1-weighted gradient echo (GRE) sequences. T2-based T2-NICQmean and T2-NICQ90th were calculated from signal intensities measured in the lesion, muscle, and fat ((SILesion – SIMuscle)/(SIFat – SIMuscle) * 100), and simple T1-based T1-Qmean from signal intensities of the lesion and muscle (SILesion/SIMuscle). Images were read by one radiologist with > 7 years and one with 1 year of experience. For statistical evaluation the Kruskal-Wallis or Mann-Whitney U-test, receiver operating characteristic (ROC) analysis with calculation of areas under the curve (AUC), and intraclass correlation coefficients (ICCs) were used.
Results Medians of T2-NICQs differed significantly when comparing infectious lesions and lymphoma manifestations in general (T2-NICQmean 20.33 vs. 10.14; T2-NICQ90th 34.96 vs. 25.52) or fungal lesions and lymphoma manifestations in particular (T2-NICQmean 19.00 vs. 10.14; T2-NICQ90th 34.49 vs. 25.25). The AUCs for T2-NICQs on the per-patient level ranged from 0.73 to 0.79. ICCs were at least > 0.85, except for intrarater testing of T2-NICQ90th (0.79).
Conclusion The overall diagnostic performance of T2-NICQs is adequate for differentiating infectious and fungal lesions from lymphoma manifestations. The results show good to excellent intra- and interrater agreement. We therefore consider NICQs helpful in the diagnostic workup of pulmonary nodules in hematological patients.
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Cardiac Autonomic and Physiological Responses to Moderate- intensity Exercise in Hypoxia
Authors: Fornasiero Alessandro , Skafidas Spyros , Stella Federico , Zignoli Andrea , Savoldelli Aldo , Rakobowchuk Mark , Pellegrini Barbara , Schena Federico , Mourot Laurent 
Published: October 2019

AbstractExercise physiological responses can be markedly affected by acute hypoxia. We investigated cardiac autonomic and physiological responses to different hypoxic training protocols. Thirteen men performed three exercise sessions (5×5-min; 1-min passive recovery): normoxic exercise at 80% of the power output (PO) at the first ventilatory threshold (N), hypoxic exercise (FiO2=14.2%) with the same PO as N (HPO) and hypoxic exercise at the same heart rate (HR) as N (HHR). PO was lower in HHR (21.1±9.3%) compared to N and HPO. Mean HR was higher in HPO (154±11 bpm, p<0.01) than N and HHR (139±10 vs. 138±9 bpm; p=0.80). SpO2 was reduced (p<0.01) to a similar extent (p>0.05) in HPO and HHR compared to N. HR recovery (HRR) and HR variability indices were similar in N and HHR (p>0.05) but reduced in HPO (p<0.05), mirroring a delayed parasympathetic reactivation. Blood lactate and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.001). During recovery oxygen consumption and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.01). Moderate HR-matched hypoxic exercise triggers similar cardiac autonomic and physiological responses to normoxic exercise with a reduced mechanical load. On the contrary, the same absolute intensity exercise in hypoxia is associated with increased exercise-induced metabolic stress and delayed cardiac autonomic recovery.
Warum und wie fördern Menschen Medizin? Spenderverhalten an Universitätskliniken in Deutschland
Authors: Ness Jorit , Heyder Ralf , Hassel Thomas , Helfers Carina , Horst Pit , Kreßirer Philipp , Lutz Roger , Metzger Sabine , Morchner Annika , Raubinger Anja , Schenke Eckhard , Stumpf Birgit , Pieper Claudia , Jöckel Karl-Heinz 
Published: October 2019

Zusammenfassung
Zielsetzung Viele Einrichtungen im Gesundheitswesen erzielen hierzulande Spenden in beträchtlichem Umfang, die Projekte über den medizinischen Versorgungsbedarf finanzieren. Die vorliegende Studie untersucht Motive, Einflussfaktoren und soziodemografische Merkmale von Spendern, die auf dem Gebiet der Universitätsmedizin Projekte in Krankenversorgung, Forschung und Lehre unterstützen.
Methodik Die acht teilnehmenden Universitätskliniken versandten an 7205 ihrer Spenderinnen und Spender einen vierseitigen Fragebogen. Es wurden soziodemografische Daten ausgewertet und persönliche Interessen und Motive im Zusammenhang mit getätigten Spenden erfragt.
Ergebnisse 60 % der 1317 Responder sind ehemalige Patienten der Einrichtung, zu deren Gunsten sie spenden. Zwei Drittel der Responder sind verheiratet, im Ruhestand und verfügen zumeist über ein monatliches Haushaltsnettoeinkommen zwischen 1500 und 2500 EUR. Die älteren Teilnehmer spenden häufiger aus Dankbarkeit für die erhaltene medizinische Versorgung, die Jüngeren aus altruistischer Motivation heraus. Es existiert ein signifikanter Zusammenhang zwischen dem Einkommen und der Bereitschaft, eine Testamentsspende vorzunehmen.
Schlussfolgerung Spender an Einrichtungen des Gesundheitswesens in Deutschland weisen heterogene Motivationslagen auf. Die Spendenmotivation ist abhängig von soziodemografischen Einflussfaktoren. Die Studie vermittelt Einblicke, wie sich Einrichtungen im Gesundheitswesen positionieren können, um Spenden für ihre zusätzlichen Bedarfe zu erhalten.