bluuebunny/crossref_metadata_2025_split huggingface dataset:
Forecasting the Frequency and Magnitude of Postfire Debris Flows Across Southern California
Authors: Kean Jason W. , Staley Dennis M. 
Published: February 2021

AbstractSouthern California has a long history of damaging debris flows after wildfire. Despite recurrent loss, forecasts of the frequency and magnitude of postfire debris flows are not available for the region like they are for earthquakes. Instead, debris flow hazards are typically assessed in a reactive manner after wildfires. Such assessments are crucial for evaluating debris flow risk by postfire emergency response teams; however, time between the fire and first rainstorm is often insufficient to fully develop and implement effective emergency response plans like those in place for earthquakes. Here, we use both historical distributions of fire and precipitation frequency and empirical models of postfire debris flow likelihood and volume to map the expected frequency and magnitude of postfire debris flows across southern California. We find that at least small debris flows can be expected almost every year, while major debris flows capable of damaging 40 or more structures have a recurrence interval between 10 and 13 years, a return interval that is comparable to a magnitude 6.7 earthquake. A sensitivity analysis to possible future changes in current fire and precipitation regimes indicates that debris flow activity in southern California is more sensitive to increases in precipitation intensity than increases in fire frequency and severity. Projected increases in rainfall intensity of 18% result in an overall 110% increase in the probability of major debris flows. Our results, in combination with an assessment of exposure, can be used to prioritize watersheds for further analysis and possible prefire mitigation.
Ensemble Kalman Filter Parameter Estimation of Ocean Optical Properties for Reduced Biases in a Coupled General Circulation Model
Authors: Kitsios V. , Sandery P. , O’Kane T. J. , Fiedler R. 
Published: February 2021

AbstractCoupled general circulation models (GCM), and their atmospheric, oceanic, land, and sea‐ice components have many parameters. Some parameters determine the numerics of the dynamical core, while others are based on our current understanding of the physical processes being simulated. Many of these parameters are poorly known, often globally defined, and are subject to pragmatic choices arising from a complex interplay between grid resolution and inherent model biases. To address this problem, we use an ensemble transform Kalman filter, to estimate spatiotemporally varying maps of ocean albedo and shortwave radiation e‐folding length scale in a coupled climate GCM. These parameters are designed to minimize the error between short term (3–28 days) forecasts of the climate model and a network of real world atmospheric, oceanic, and sea‐ice observations. The data assimilation system has an improved fit to observations when estimating ocean albedo and shortwave e‐folding length scale either individually or simultaneously. However, only individually estimated maps of shortwave e‐folding length scale are also shown to systematically reduce bias in longer multiyear climate forecasts during an out‐of‐sample period. The bias of the multiyear forecasts is reduced for parameter maps determined from longer DA cycle lengths.
Understanding Ground Rupture Due to Groundwater Overpumping by a Large Lab Experiment and Advanced Numerical Modeling
Authors: Nardean S. , Ferronato M. , Zhang Y. , Ye S. , Gong X. , Teatini P. 
Published: February 2021

AbstractGround rupture due to groundwater pumping is a major environmental hazard accompanying land subsidence in some areas. Ground ruptures usually develop when a significant compaction affects a sedimentary sequence with peculiar geological conditions, for example, the presence of a shallow bedrock with buried ridges. A laboratory test was developed with the aim at improving our understanding of the mechanisms responsible for rupture generation in this particular hydrogeological setting, typical, for instance, of the Guangming village, China. A 0.8‐m high concrete prism, representing a rocky ridge, was placed in a 4.0‐m long, 1.8‐m wide, and 1.4‐m high box and buried by alluvial material. The box was saturated and then drained, with the formation of a main crack above the prism‐shaped ridge. The measured water content, vertical displacements, strains, rupture initiation, and growth are analyzed through an original coupled 3D‐numerical model, simulating the variably saturated groundwater flow in a deformable and fractured porous medium. To our knowledge, this is the first application of such a kind of model to a lab‐scale experiment. Despite the uncertainty on the material parameters, the numerical model allows satisfactorily reproducing the observed groundwater flow, land subsidence, and rupture features (depth and width). The rupture dynamics is captured in part as well, despite the employment of a simple Mohr–Coulomb failure criterion and although other forces (e.g., electrochemical) may likely play a role at the metric scale of the lab test. The modeling outcomes provide a clear view on how the rupture develops from the surface and propagates downward.
Installation Matters: Implications for In Situ Water Quality Monitoring
Authors: Erwin Elizabeth G. , McLaughlin Daniel L. , Stewart Ryan D. 
Published: February 2021

AbstractNovel in situ sensor technologies can measure water chemistry at high temporal frequencies, yet few studies have evaluated how installation affects measurements. In this study, we assessed the effects of commonly used protective housings on in situ sensor readings. Working in two mountain streams, we colocated specific conductance sensors in four different housing types that varied in openings for water exchange (mesh, screen, holes, and open). We compared measured conductance values through time and performed repeated salt tracer additions to evaluate the influence of housing type on calculated discharge. Sensors readings in mesh and, to a lesser extent, screen housings frequently diverged from housings with larger openings (i.e., holes and open), indicating reduced water exchange between stream water and housed sensors. Further, mesh and screen housings recorded more damped and delayed response to salt tracer additions compared to the other two housings, resulting in markedly different discharge values. From these findings, we recommend that water chemistry sensors should be deployed in a protective housing with large openings for sufficient water exchange.
Incorporating the Memory Effect of Turbulence Structures Into Suspended Sediment Transport Modeling
Authors: Tsai Christina W. , Huang Shih‐Hsun , Hung Serena Y. 
Published: February 2021

AbstractModeling of the random movement of fine sediment particles in open‐channel turbulent flow is mostly built upon the memoryless Brownian motion process. Such a process describes the chaotic behavior of small particles without considering temporal correlations in terms of the particle moving velocity and direction (i.e., memory). However, when particles are transported in time‐persistent turbulent flow, the movements of the suspended particles may exhibit persistency that depends on the various temporal durations of turbulent flow structures—such persistence results in direction and magnitude variations in the velocity of the fine moving particles. The diffusion property of the particles may then deviate from normal diffusion. The conventional memoryless random walk models may not provide a comprehensive description of the particle diffusion process for the duration of turbulence structures when the particles are subject to memory effects. In this study, a novel random walk model is proposed to present the temporal correlation of the suspended sediment particle velocity caused by turbulence structures in open channel flow. The probabilistic properties of the proposed model are discussed. In particular, enhanced physical insights are obtained regarding the particle diffusion behavior in turbulent flows. Numerical simulations are conducted to demonstrate that, similar to the conventional memoryless random walk models, the proposed model shows normal diffusion for long‐term observations, despite its local superdiffusion behavior. The effective diffusion coefficient of the proposed stochastic process on a long‐term time scale is formulated.
Predicting Latent and Sensible Heat Fluxes in Stream Temperature Models: Current Challenges and Potential Solutions
Authors: Moore R. D. , Leach J. A. 
Published: February 2021

AbstractStream temperature studies typically use either the Penman combination equation (PCE) or empirical wind functions to compute the latent heat flux, which can be an important control on daily maximum water temperature. The sensible heat flux is usually computed from the latent heat flux via the Bowen ratio or a bulk transfer model. Unfortunately, both the PCE and empirical wind functions involve challenges. The PCE is inappropriate for application to subdaily stream evaporation because, as implemented in many stream temperature studies, it does not account for energy associated with warming or cooling of the water column or bed heat fluxes. The PCE thus tends to overestimate evaporation under conditions typical of warm summer days during the diurnal warming phase, which is when evaporation is likely to be an important heat loss mechanism. Empirical wind functions involve substantial uncertainty given the broad range of coefficient values that have been reported in the literature and the lack of above‐stream meteorological data to use in their application. We provide suggestions for improving current practice and also identify research directions to support development of robust approaches to computing the latent and sensible heat fluxes.
Compound Cocktail Inhibits Influenza Viral Pneumonia via Phospholipase Cγ1 Phosphorylation-Related Necroptosis and Partial Autophagy in Natural Killer Cells
Authors: Ma Rong , Ma Rui-Qing , Chen Bei , Wang Li-Yu , Fan Xiao-Yong 
Published: February 2021

AbstractInfluenza viral infections are prone to global outbreaks and cause pneumonia in affected populations. High morbidity and mortality caused by pneumonia occur during an influenza pandemic. Antivirals or control of inflammation is the primary means of influenza treatment. A compound cocktail composed of arctiin, daidzein, glycyrrhizic acid, and liquiritin inhibited mouse pneumonia resulting from a PR8 viral infection and caused a weight gain after oral administration. Natural killer cell activating receptors, both Ly49D and Ly49H in the lungs, were increased in the treatment in mice. In H3N2 virus-infected natural killer-92MI cells, the cocktail treatment had different effects on phosphorylation sites of phospholipase Cγ1 (PLCγ1) and killed infected cells through necroptosis or late apoptosis, in which RIP3 was increased and both caspase-3 and phosphorylated-JNK in the cells were downregulated. Acid phosphatase activity in viral-infected natural killer-92MI cells was induced by the compound cocktail treatment, which could be related to the p62 decrease in natural killer-92MI cells. In addition, an autophagic flux induction was observed in alveolar basal epithelial cells (A549). Protein p65, but not phosphorylated-p65, was significantly decreased by the treatment. Our results indicate that the compound cocktail strengthened the phosphorylation of PLCγ1-related necroptosis and partial autophagy in natural killer cells, which could yield an inhibitory effect on viral pneumonia in influenza.
Bioaccessibility and Absorption of Flavonoid C-glycosides from Abrus mollis Using Simulated Digestion, Caco-2 Cell, and In Situ Single-pass Perfusion Models
Authors: Shen Wei , Hu Xiaolong , Niu Yajun , Lu Yimeng , Wang Baolin , Wang Hao 
Published: February 2021

Abstract
Abrus mollis is commonly used as a traditional Chinese medicine for the treatment of liver diseases due to its hepatoprotection and anti-inflammation, but the absorption properties of its main bioactive ingredients remain unclear. Our previous studies verified that the flavonoid C-glycosides, including vicenin-2 (1), isoschaftoside (2), and schaftoside (3), were the major active components in A. mollis for hepatic protection against nonalcoholic fatty liver disease, hepatitis, and hepatic fibrosis. This study investigated the bioaccessibility and transport mechanisms of total flavonoid C-glycoside, as well as vicenin-2 (1), isoschaftoside (2), and schaftoside (3), in A. mollis by simulated digestion and use of the Caco-2 cell model. Moreover, this study attempted to verify their absorption properties by in situ gastrointestinal perfusion in rats. Total flavonoid C-glycoside and 1, 2, and 3 exhibited similar bioaccessibility of 84.58%, 85.13%, 83.05%, and 81.65% respectively after simulated digestion. The transport of total flavonoid C-glycoside in the Caco-2 cell model increased with the concentration, and the transport showed saturation characteristics with the time and concentration of total flavonoid C-glycoside to a certain degree. The Papp values of total flavonoid C-glycoside and the 3 flavonoid C-glycosides were significantly improved by verapamil, probenecid, and EDTA-Na2. Their absorption properties in the gastrointestinal tract were consistent with that found in Caco-2 cells, and superior absorption rates were observed in the duodenum and jejunum. The absorption pattern of total flavonoid C-glycoside may involve multiple transport pathways, including active transport, passive diffusion, and the paracellular pathway. TFC was actively pumped out by P-glycoprotein and multidrug
resistance-associated protein. These results revealed that the bioaccessibility and intestinal absorption characteristic of total flavonoid C-glycoside were consistent with the 3 major flavonoids.
DMAP-Catalyzed Reaction of Diethyl 1,3-Acetonedicarboxylate with 2-Hydroxybenzylideneindenediones: Facile Synthesis of Fluorenone-Fused Coumarins
Authors: Shkoor Mohanad , Bayari Raghad 
Published: February 2021

AbstractThe base-catalyzed reaction of diethyl 1,3-acetonedicarboxylate with 2-hydroxybenzylidene indenediones was studied. The reaction provides a facile and expeditious protocol for the synthesis of natural product inspired fluorenone-fused coumarins in good to very good yields. This process resembles a combination of domino Michael–intramolecular Knoevenagel–aromatization–lactonization reactions in a single step. Although this reaction operates with many bases, the best yields were obtained with DMAP as a catalyst. This protocol could open new potential avenues for the synthesis of fused coumarins by the reaction of substituted β-keto esters with different 2-(2-hydroxybenzylidenes) of 1,3-dicarbonyl compounds.
(3+2)-Cycloaddition of Donor–Acceptor Cyclopropanes with Thiocyanate: A Facile and Efficient Synthesis of 2-Amino-4,5-dihydrothiophenes
Authors: Werz Daniel B. , Jacob Anu , Barkawitz Philip , Andreev Ivan A. , Ratmanova Nina K. , Trushkov Igor V. 
Published: February 2021

AbstractAn easy and efficient route to obtain 2-amino-4,5-dihydrothiophenes is presented. A formal (3+2)-cycloaddition of donor–acceptor cyclopropanes and ammonium thiocyanate catalyzed by Yb(OTf)3 delivers the desired products in good to excellent yields. A broad range of functional groups is tolerated during this process.
Outcomes of Combined Unicondylar Knee Arthroplasty and Anterior Cruciate Ligament Reconstruction
Authors: Aslan Hakan , Çevik Hüseyin Bilgehan 
Published: February 2021

AbstractYoung and more active patients with medial compartmental osteoarthritis (OA) in conjunction with anterior cruciate ligament (ACL) deficiency are challenging for orthopaedic surgeons. The aim of the present study was to examine the early–mid clinical and radiological outcomes of combined Oxford unicondylar knee arthroplasty (UKA) and ACL reconstruction for the patients presenting ACL deficiency and concomitant medial compartment symptomatic OA. Twelve patients were included in the study. All patients were treated by combination of ACL reconstruction with medial UKA. The varus–valgus angles of the tibial and femoral components, and pathological radiolucent lines were measured on anteroposterior and lateral knee radiographs. Clinical evaluations include knee osteoarthritis outcome score (KOOS pain, symptom, daily life, sports, and quality of life), Oxford knee score (OKS), EQ-5D-3L, and EQ-visual analog scale (VAS). All the patients were followed up for an average of 45.6 months. The leg alignment showed 3.6 degrees ± 1 of varus deformity before surgery and 2.6 degrees ± 1 of valgus after surgery. With the exception of KOOS sports (p > 0.001), the KOOS pain, symptom, daily life, and quality of life, OKS, EQ-5D-3L, and EQ-VAS improved significantly after surgery (p < 0.001). Preoperative knee instability showed anterior translation of 5 to 10 mm in eight patients and >10 mm in four patients. There were no complications at follow-up. The early–mid clinical data have shown that UKA in conjunction with ACL reconstruction has revealed promising results. However, long-term follow-up studies are required to confirm the combined procedure in these patients.
Impact of Biological Sex on Complications, Lengths of Stay, Readmission Rates, and Costs of Care Following Primary Total Knee Arthroplasty
Authors: Swiggett Samuel J. , Mannino Angelo , Vakharia Rushabh M. , Ehiorobo Joseph O. , Roche Martin W. , Mont Michael A. , Erez Orry 
Published: February 2021

AbstractThe impact of gender on total knee arthroplasty (TKA) postoperative complications, readmission rates, and costs of care has not been often evaluated. Therefore, the purpose of this study was to investigate which sex had higher rates of: (1) medical complications; (2) implant complications; (3) lengths of stay (LOSs); (4) readmission rates; and (5) costs after TKA. A query was performed using an administrative claims database from January 1, 2005, to March 31, 2015. Patients who had TKAs were identified using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes. Males and females were filtered separately and matched according to age and various medical comorbidities leading to 1,590,626 patients equally distributed. Primary outcomes analyzed included 90-day medical complications, LOSs, 90-day readmission rates, in addition to day of surgery and total global 90-day episode of care costs. Pearson's chi-square analyses were used to compare medical complications and readmission rates. Welch's t-tests were used to test for significance in matching outcomes and costs. A p-value of less than 0.01 was considered statistically significant. Males had a smaller risk of complications than women (1.35 vs. 1.40%, p < 0.006) and higher rates of implant-related complications (2.28 vs. 1.99%, p < 0.0001). Mean LOSs were lower for males: 3.16 versus 3.34 days (p < 0.0001). The 90-day readmission rates were higher in men (9.67 vs. 8.12%, p < 0.0001). This study demonstrated that males undergoing primary TKA have lower medical complications and shorter LOSs then their female counterparts. However, males have higher implant-related complications, readmission rates, and costs of care.
Predictors of Mid- to Long-Term Outcomes in Patients Experiencing a Knee Dislocation: A Systematic Review of Clinical Studies
Authors: Smith John-Rudolph H. , Belk John W. , Friedman Jamie L. , Dragoo Jason L. , Frank Rachel M. , Bravman Jonathan T. , Wolcott Michelle L. , McCarty Eric C. 
Published: February 2021

AbstractKnee dislocations (KDs) are devastating injuries for patients and present complex challenges for orthopaedic surgeons. Although short-term outcomes have been studied, there are few long-term outcomes of these injuries available in the literature. The purpose of this study is to determine factors that influence mid- to long-term clinical outcomes following surgical treatment of KD. A review of the current literature was performed by searching PubMed, the Cochrane Library, and Embase to identify clinical studies published from 2010 to 2019 with a minimum 2-year follow-up that reported outcomes following surgical treatment of KDs. Ten studies (6 level III, 4 level IV) were included. At mid- (2–10 y) to long-term (>10 y) follow-up, concomitant arterial, cartilage, and combined meniscus damage were predictive factors for inferior Lysholm and International Knee Documentation Committee (IKDC) scores when compared with patients without these associated injuries. Although concomitant neurological damage may influence short-term outcomes due to decreased mobility, at longer follow-up periods it does not appear to predict worse clinical outcomes when compared with patients without concomitant neurological injury. Frank and polytrauma KDs have been associated with worse mid- to long-term outcomes when compared with transient and isolated KDs. Patients who underwent surgery within 6 weeks of trauma experienced better long-term outcomes than those who underwent surgery longer than 6 weeks after the initial injury. However, the small sample size of this study makes it difficult to make valid recommendations. Lastly, female sex, patients older than 30 years at the time of injury and a body mass index (BMI) greater than 35 kg/m2 are factors that have been associated with worse mid- to long-term Lysholm and IKDC scores. The results of this review suggest that female sex, age >30 years, BMI >35 kg/m2, concomitant cartilage damage, combined medial and lateral meniscal damage, KDs that do not spontaneously relocate, and KDs associated with polytrauma may predict worse results at mid- to long-term follow-up.
Density functional theory study of single-molecule ferroelectricity in Preyssler-type polyoxometalates
Authors: Wang Fei , Lang Zhongling , Yan Likai , Stroppa Alessandro , Poblet Josep M. , de Graaf Coen 
Published: February 2021

A detailed study on the single-molecule ferroelectric property of Preyssler-type polyoxometalates (POMs), [M3+P5W30O110]12− (M = La, Gd, and Lu), is performed by density functional theory calculations. Linked to one H2O molecule, the cation (M3+) encapsulated in the cavity of the Preyssler framework is off-centered, and it generates a permanent dipole, which is essential for a ferroelectric ground state. Accompanied with a 180° rotation of H2O, the switching of M3+ between two isoenergetic sites on both sides of the cavity results in a calculated barrier of 1.15 eV for Gd3+, leading to the inversion of electric polarization. The height of the barrier is in good agreement with the experimentally measured barrier for the Tb3+ ion, whose ionic radius is similar to Gd3+. The total polarization value of the crystal is estimated to be 4.7 µC/cm2 as calculated by the modern theory of polarization, which is quite close to the experimental value. Considering that the order of contributions to the polarization is M3+–H2O &gt; counter-cations (K+) &gt; [P5W30O110]15−, the interconversion of M3+–H2O between the two isoenergetic sites is predicted to be the main origin of ferroelectricity with a polarization contribution of 3.4 µC/cm2; the K+ counter-cations contribute by 1.2 µC/cm2 and it cannot be disregarded, while the framework appears to contribute negligibly to the total polarization. Our study suggests that a suitable choice of M3+–H2O could be used to tune the single-molecule ferroelectricity in Preyssler-type polyoxometalates.