Low Discharge Research Articles

Reliability of reservoir inflow for supporting the operation simulation model of multi reservoir

This research intends to analyze the inflow reliability of the Tugu-Bagong multi-reservoir. The utilization of Tugu Dam is as follows: for fulfilling the irrigation water need of Ngasinan Irrigation Area an area is 1,200 ha, supplying 12 l/s of raw water, controlling the yearly flood in Trenggalek Regency with the discharge is 76.21 m3/s, as the potency of mini-hydro electrical generation (PLTM) in the amount of 0.40 MW, and as the tourism means. However, Bagong Dam, besides being utilized for flood control, is also utilized for supplying raw water, irrigation, and domestic water; for water resources conservation; and recreation or tourism. The methodology consists of collecting the rainfall data and watershed parameters like watershed area, infiltration coefficient each for dry and rainy seasons, retention coefficient, SMC value, etc.; to analyze the dependable discharge due to the rainfall analysis input in 4 discharge conditions: dry season discharge, low water discharge, normal water discharge, and sufficient water discharge. The result of inflow reliability is hoped to be able to support the operation simulation modeling of the Tugu-Bagong multi-reservoir.

Mixing of the Connecticut River Plume During Ambient Flood Tides: Spatial Heterogeneity and Contributions of Bottom‐Generated and Interfacial Mixing

AbstractThe Connecticut River plume is influenced by energetic ambient tides in the Long Island Sound receiving waters. The objectives of this modeling study are (a) characterizing the spatial heterogeneity of turbulent buoyancy fluxes, (b) partitioning turbulent buoyancy fluxes into bottom‐generated and interfacial shear contributions, and (c) quantifying contributions to plume‐integrated mixing within the tidal plume. The plume formed during ambient flood tides under low river discharge, spring tides, and no winds is analyzed. Turbulent buoyancy fluxes (B) and depth‐integrated B through the plume (Bd) are characterized by pronounced spatial heterogeneity. Strong mixing (Bd ∼ 10−5‐10−4 m3/s3) occurs near the mouth, in the nearfield plume turning region, over shoals, and nearshore shallow areas. Low to moderate mixing (Bd ∼ 10−8‐10−6 m3/s3) occupies half the plume. Buoyancy fluxes are first partitioned based on the depth of the shear stress minimum between plume‐generated and bottom‐generated shear maxima. Four other tested partitioning methods are based on open channel flow and stratified shear flow parameterizations. Interfacial and bottom‐generated shear contribute to different areas of intense and moderate mixing. All methods indicate a significant plume mixing role for bottom‐generated mixing, but interfacial mixing is a bigger contributor. Plume‐integrated total and interfacial mixing peak at max ambient flood and the timing of peak bottom‐generated mixing varies among partitioning methods. Two‐thirds of the mixing occurs in concentrated intense mixing areas. A parameter space with the ambient tidal Froude number and plume thickness to depth ratio as axes indicates many tidally modulated plumes are moderately to dominantly influenced by bottom‐generated tidal mixing.

Self-supporting sulfonated covalent organic framework as a highly selective continuous membrane for vanadium flow battery

The application of sulfonated covalent organic frameworks (SCOFs) in vanadium redox flow battery (VRFB) is limited by the nano-scale non-sieving pores and low additive amount in mixed matrix membranes. Herein, a self-supporting continuous SCOF membrane interlaced with Nafion chains (SCOF/Nf) is proposed to possess high H+/Vn+ selectivity via the wedge-tenon like reinforce structure. The continuous self-supporting SCOF layer provides crystalline ordered dense sulfonic acid groups for proton hopping and contributes to the considerably high proton conductivity (143.9 mS cm−1, 25 °C) at a very low swelling ratio (3.1 %). The flexible Nafion polymer chains can be inserted into the pores of SCOF by hydrogen bonds and ionic interactions, reducing the pore size from 15.0 Å to 5–10 Å for efficiently sieving H+/Vn+ ions. With a SCOF weight proportion of 0.6, the SCOF/Nf-0.6 membrane achieves to a high energy efficiency and extremely low discharge capacity decay rate (85.5 % and 0.13 % per cycle at 100 mA cm−2, respectively), which are much superior to the most state-of-the-art Nafion and COFs based ion conductive membranes. With the interlaced Nafion layer, the SCOF/Nf-0.6 membrane keeps stable and intact in the 500-cycle test (>900 h) in VRFB. The application of SCOF in VRFB from mixed matrix membranes to self-supporting continuous membrane provides an efficient way to maximize the function of the crystalline ordered two-dimensional materials.

Treatment of greywater with nanofiltration for nutrient removal – 2-year experience from Helsingborg

Abstract Source-separated sanitation and greywater treatment have become an increasingly attractive alternative to traditional wastewater management systems in recent years due to their potential to combat water scarcity, ease resource recovery, and meet tightening effluent demands. In Helsingborg, Sweden, source-separated wastewater from the new city district of Oceanhamnen is being collected and treated in a new treatment plant (RecoLab) to test, among other issues, how efficient greywater treatment can be in achieving low discharge limits for pollutants. The greywater treatment consists of activated sludge treatment, drum filter micro-sieving, and nanofiltration. In the first two years of operation, the robustness of the treatment system during periods with extreme conditions, e.g., very low and very high organic matter concentrations, was tested. The combination of biological treatment and nanofiltration has achieved stable effluent concentrations below 10 mg/L chemical oxygen demand, 2 mg/L total nitrogen, and 0.2 mg/L total phosphorus as average values for 22 months of operation with an average flow of 43 m3/day. The treatment system for greywater treatment thus shows the possibility to achieve low discharge limits and meet the new proposed effluent demands of the EU Urban Wastewater Treatment Directive.

Hydro‐Sedimentary Processes of a Plunging Hyperpycnal River Plume Revealed by Synchronized Remote Imagery and Gridded Current Measurements

AbstractThe present knowledge of plunging hyperpycnal river plumes is mainly based on two‐dimensional (confined) laboratory experiments. Several hypotheses on three‐dimensional (unconfined) flow processes have been made, but not tested in situ. In this field study, the dominant three‐dimensional hydro‐sedimentary processes related to unconfined plunging were elucidated by synchronizing autonomous time‐lapse camera images with boat‐towed acoustic Doppler current profiler measurements. It was found that the flow field complies with two‐dimensional conceptualizations along the plume centerline. Perpendicular to the centerline, the plume slumped laterally due to its density excess and simultaneously converged laterally due to its vertical divergence. This combination led to a narrowing of the plume near the surface, resulting in a sediment‐rich triangle‐shaped pattern on the surface near the inflow, and a rather stable width near the bed. The formation of secondary flow cells transporting riverine water and suspended particulate matter (SPM) away from the plume near the bed, up toward the surface and back toward the plume near the surface, was revealed. An increase of the average SPM concentration and the SPM flux in the main flow direction indicates net sediment erosion under the investigated conditions of high discharge and sediment load. This suggests transient storage of sediment during conditions of lower discharge and sediment load, and high morphological activity in the plunging area. These findings allowed extending a classical conceptual plunging model to laterally unconfined sediment‐laden plunging inflows for conditions of well‐mixed ambient water in the plunging region and inflow densimetric Froude numbers exceeding 1, common in nature.

Hydropower Development and Economic Growth in Nepal: Challenges and Prospects

Nepal is rich in water resources, and hydropower development has been a key issue for the country's socio-economic development. But, it needs to produce huge amounts of electricity to support economic activities and growth, though it faces challenges. The paper attempts to fill this gap by studying hydropower development in support of economic growth and overall development, and further discussing its challenges through a literature review analysis and Key Informant Interviews. Economically, Nepal has more than 42000 MW of hydropower generation capacity, but the present generation capacity is 2945 MW, though only below more than 50 percent of the total generation capacity works out in the dry season due to low water discharge and faces a deficiency of electricity. Nepal also imports electricity from India to fulfill domestic demands in the season. There is a gap in the demand and supply lines. Hydropower has become a de-facto reality in light of economic development and the production of hydropower is crucial as Nepal exported electricity of Rs.15.4 billion worth last year. However, this study shows that the prospect of hydropower development is optimistic, though, there are several challenges in terms of priorities of needy projects, investment, environment-forest-land policies, and governance aspects. If pragmatic policy, effective governance, and leadership interventions are adopted on time, challenges can be overcome.

Use of interrupted time-series analyses in evaluating health economic outcomes following implementation of multilayer water-tight wound closure in a primary total joint arthroplasty population.

Aim: Total joint arthroplasty (TJA) with multi-layer, watertight closure (MLWC) using knotless barbed suture and 2-octyl cyanoacrylate plus polymer mesh tape was compared with conventional closure (CC) using Vicryl™ sutures and staples. Patients & methods: Electronic medical records of patients undergoing TJA (1574: total knee arthroplasty; 580: total hip arthroplasty; 13: unknown) from a single surgeon at a US hospital (CC 2011 to 2013; MLWC 2015 to 2020) were reviewed. Outcomes were length of stay (LOS), discharge to skilled nursing facility (SNF), 90-day surgical site infection (SSI) and 90-day readmission. Logistic regression controlled for baseline characteristics. Adjusted interrupted time series (ITS) analyses accounted for decreasing trends in LOS and SNF discharge over time. Results: Among 2167 TJA cases (mean [standard deviation] age 66.0 [9.7]years, 53.3% female), 906 received CC and 1261 received MLWC. Bivariate analysis showed no statistically significant differences in 90-day SSI rates; however, MLWC patients had 60% lower 90-day readmission rates (1.5 vs 3.8%, p<0.05), 44% lower LOS (1.4 vs 2.5days, p<0.05) and 40% lower discharge rates to a skilled care facility (8.5 vs 14.1%, p<0.05). Multivariable analyses showed CC patients were 2.45-times more likely to be readmitted within 90days, 1.88-times more likely to be discharged to SNF and had 1.67-times longer LOS compared with MLWC. ITS analyses showed a sharp decline in LOS (0.9days) and discharge to SNF (5.6% incidence) after implementation of MLWC, followed by no further changes for the remainder of the study period. Conclusion: MLWC was associated with ≥40% reduction in 90-day readmission, LOS and SNF discharge compared with TJA CC. LOS and discharge rate to SNF declined sharply after the implementation of MLWC.

Metal contamination, their ecological risk, and relationship with other variables in surface sediments of urban rivers in a big city in Asia: case study of Hanoi, Vietnam.

Urban rivers are significantly impacted by anthropogenic pressure. This study presents the updated assessment of the concentrations of 11 metals and other variables (pH, total organic carbon (TOC) and nutrients (total nitrogen, total phosphorus, and total silica)) in the sediments of four urban rivers in inner Hanoi city, Vietnam, during the period 2020-2022. The mean concentrations of Fe, Zn, As, and Cr were higher than the permissible values of the Vietnam National technical regulation on the surface sediment quality. Moreover, Zn and Cr were at the severe effect level of the US EPA guidelines for sediment quality. The calculation of pollution indices (Igeo and EF) demonstrated that Mn, Ni, and Fe were from natural sources whereas other metals were from both anthropogenic and natural sources. The ecological risk index revealed that metals in Hanoi riverine sediments were classified at considerable ecological risk. High values of metals, TOC, and nutrients in the sediments of these urban rivers mostly originate from the accumulation of untreated urban wastewater that is enhanced by low river discharge. Our results may provide scientific base for better management decisions to ensure environmental protection and sustainable development of Hanoi city.

Preoperative hypocoagulative state is an independent risk factor for wound complications and infection in gender-affirming bottom surgeries

BackgroundBottom gender affirmation surgery (GAS) involves the risks of bleeding and associated complications. Effective preoperative blood management is paramount across surgical disciplines with international normalized ratio (INR)≤1.5 advised prior to certain surgeries. This study aimed to examine the proportion of patients who were hypocoagulative before they underwent bottom GAS and assess the influence of hypocoagulability on their 30-day post-operative outcomes. MethodA retrospective study on female-to-male (FtM) and male-to-female (MtF) bottom GAS was performed based on American college of surgeons national surgical quality improvement program (ACS-NSQIP) database from 2005 to 2021. Patients with hypocoagulation were identified when PTT> 60 s, PT > 30 s, and/or INR> 2. Multivariable logistic regression was used to compare the 30-day perioperative outcomes between patients with hypocoagulation and controls. ResultsIn this study, 380 patients (182 FtM, 198 MtF) with hypocoagulation and 1176 controls (886 FtM, 310 MtF) were included. Mortality and organ system complications were infrequent in both groups. Patients with hypocoagulation had higher wound complication rates (13.68% vs. 2.64%, aOR 2.858, p < 0.01), especially wound dehiscence (10.00% vs. 0.60%, aOR 4.424, p < 0.01) and organ space infection rates (2.11% vs. 0.26%, aOR 12.77, p < 0.01). Additionally, patients with hypocoagulation had higher sepsis (0.79% vs. 0.09%, aOR 15.508, p = 0.04) and readmission rates (4.74% vs. 2.47%, aOR 1.919, p = 0.03), but lower rates of discharge not to home (7.92% vs. 25.38%, aOR 0.324, p < 0.01). ConclusionPreoperative hypocoagulative state is observed in approximately a quarter of the patients undergoing bottom GAS and is an independent risk factor for increased risks of 30-day wound complications and infections. Therefore, meticulous monitoring of preoperative hemostasis and implementing hemostasis control before surgery may be necessary. Thus, it may be advisable to discontinue oral anticoagulants before the surgery.

Remote Sensing-Based Extension of GRDC Discharge Time Series - A Monthly Product with Uncertainty Estimates

The Global Runoff Data Center (GRDC) data set has faced a decline in the number of active gauges since the 1980s, leaving only 14% of gauges active as of 2020. We develop the Remote Sensing-based Extension for the GRDC (RSEG) data set that can ingest legacy gauge discharge and remote sensing observations. We employ a stochastic nonparametric mapping algorithm to extend the monthly discharge time series for inactive GRDC stations, benefiting from satellite imagery- and altimetry-derived river width and water height observations. After a rigorous quality assessment of our estimated discharge, involving statistical validation, tests and visual inspection, results in the extension of discharge records for 3377 out of 6015 GRDC stations. The quality of discharge estimates for the rivers with a large or medium mean discharge is quite satisfactory (average KGE value > 0.5) however for river reaches with a low mean discharge the average KGE value drops to 0.33.The RSEG data set regains monitoring capability for 83% of total river discharge measured by GRDC stations, equivalent to 7895 km3/month.

Incidence, risk factors and impact of anemia after elective neurosurgery: A retrospective cohort study

ObjectivesAnemia after surgery is common and is associated with adverse clinical outcomes. Understanding the incidence and risk factors for postoperative anemia is important to reduce anemia-related complications and blood transfusion. There is lack of data regarding postoperative anemia and its contributing factors in neurosurgery. This study evaluates the incidence and risk factors of postoperative anemia, and its impact on clinical outcomes. MethodsThis was a single centre, retrospective study of patients who underwent elective neurosurgery over seven months. Data regarding age, gender, body mass index, American Society of Anesthesiologists (ASA) physical status, diagnosis, surgery, preoperative hemoglobin, surgery duration, intraoperative blood loss and red blood cell (RBC) transfusion, dose of tranexamic acid, intraoperative fluid balance, years of surgeon’s experience, postoperative hemoglobin, postoperative RBC transfusion, Glasgow Coma Scale (GCS) score at hospital discharge, and duration of postoperative intensive care unit and hospital stay were collected. Logistic regression was used to identify predictors of postoperative anemia. ResultsThe incidence of postoperative anemia was 11.3% (116/1025). On univariate analysis; age, preoperative hemoglobin, surgery duration, gender, ASA grade, surgery type, and surgeon’s experience were associated with postoperative anemia. Lower preoperative hemoglobin (p<0.001) and non-tumor surgery (p<0.001) were predictive of postoperative anemia on multivariate analysis. Postoperative anemia resulted in increased RBC transfusion (p<0.001) and lower GCS score at discharge (p=0.012). ConclusionsAtleast one in ten patients undergoing elective neurosurgery develop postoperative anemia. Lower preoperative hemoglobin and non-tumor surgery predict anemia. Anemia results in increased RBC transfusion and lower discharge GCS score.

Assessing the salinization mechanisms of coastal brackish springs

Brackish springs have been extensively reported in Mediterranean coastal carbonate formations. The phenomenon is puzzling because these springs may discharge high flow rates with significant salinities at elevations of several meters above sea level. Although these springs have been studied for millennia (since the ancient Greeks), controversy persists. In essence, they are typically assumed to consist of a karstic conduit bringing fresh groundwater that meets a saltwater conduit at a branching point, where the brackish mixture flows up to the spring mouth. Here, we analyze the hydraulics of the system for two simple cases, depending on whether seawater flow occurs through an open conduit or a porous aquifer. To this end, we derive the equations governing variable-density turbulent flow through the conduits. These turn out to be similar to the traditional ones, except that (1) Bernouilli’s head (energy per unit weight) is substituted by the energy per unit volume, and (2) this energy is not a potential, as a flow path dependent term needs to be added. We solve these equations to obtain the characteristic functions relating fresh to seawater discharge depending on spring concentration. These functions are specific to every brackish spring and representative of the karst system and salinization mechanism. They allow us to show that the spring salinity is mostly controlled by the weight of the water column flowing towards the spring mouth (for low flow rates) and by energy dissipation (for high flow rates). When concentration and flow rate data are available, it is possible to characterize: (1) the resistance of the upwards conduit from the response at high flow rate; (2) the depth of the branching point from the concentration at low discharges; and (3) the hydraulic resistance of the seawater conduit from the slope of concentration vs. flow rate at low spring discharges. These patterns are compared to field data from three different springs, which yields insights on the conceptual model governing every particular spring.

Double-phase electrolyte enabling the long-lasting redox mediation in Li–O2 batteries

The achievement of practical Li–O2 batteries is impeded by their low discharge capacity, large charge overpotential, and short lifespan. In general, the use of electrolyte with a high-donor-number solvent such as dimethyl sulfoxide (DMSO) is able to drive the solution-mediated pathway, alleviating the premature passivation of cathode from the surface-mediated Li2O2 film growth, gaining large Li2O2 toroidal particles, and extending the discharge lifetime. However, direct electrochemical decomposition of Li2O2 toroidal products typically occurs at a high charge potential owing to the poor solid-solid contact between cathode catalysts and Li2O2 toroids. Besides, DMSO-based electrolytes are unstable to Li anode, leading to undesired parasitic reactions. To overcome above issues, herein, a double-phase electrolyte composed of 10-methylphenothiazine (MPT)-dissolved DMSO-based catholyte and octyltrimethoxysilane (TOOS)-based anolyte is designed taking advantages of the immiscibility of DMSO and TOOS solvents and the insolubility of MPT in TOOS. Benefiting from the rapid liquid-solid reaction between MPT+ and Li2O2 products, the blocked MPT shuttling in TOOS, and the good compatibility of TOOS-based electrolyte to Li anode, the assembled Li–O2 battery delivers a reduced charge overpotential and a robust cyclability over 250 cycles. This study provides a promising strategy for electrolyte design towards next-generation high-performance Li–O2 batteries.

Association between neighborhood household income and inpatient atrial fibrillation outcomes

BackgroundThe impact of socioeconomic status on the clinical outcomes of patients admitted to the hospital for atrial fibrillation (AF) is not well described. ObjectiveThe purpose of this study was to determine the association between median neighborhood household income (mNHI) and clinical outcomes among patients admitted to the hospital for AF. MethodsWe retrospectively analyzed primary AF hospitalizations from the United States National Inpatient Sample between 2016 and 2020. The analyzed sample was divided into quartiles based on the mNHI in the zip code of the patient’s residence. The lowest quartile was used as the reference category. Study outcomes included inpatient procedure utilization (ablation, cardioversion, percutaneous left atrial appendage closure), length of stay, cost, mortality, and disposition. Weighted multivariable logistic and linear regression, adjusting for multiple patient and hospital-level characteristics, was performed. ResultsPatients in the highest mNHI quartile had lower comorbidity burden, lower in-hospital mortality (odds ratio [OR] 0.78; 95% confidence interval [CI] 0.7–0.87; P <.001), lower discharges to care facility (OR 0.86; 95% CI 0.83–0.9; P <.001), shorter length of stay (adjusted mean difference –0.26; 95% CI –0.30 to –0.22; P <.001), higher procedure utilization, and higher health care costs ($12,124 vs $10,018) compared to the lowest mNHI quartile patients. ConclusionWe identified significantly higher in-hospital mortality and lower procedural/resource utilization in patients living in lower-income neighborhoods compared to higher-income neighborhoods. Further research is needed to better understand the drivers of these disparities and the strategies to improve health care disparities between socioeconomic groups.

A System and Method for Retrieving Energy Potential through Irrigation Gate of an Agricultural Dependent Hydro Power Plant

The modern economics depends on the electrical energy and the share of decarburized electrical energy is the base of 2050 net zero emission targets. Non-fossil fuel and fossil fuel energy resources are the integral part of net zero energy system. The net zero emission activities are affected by increasing demand of electricity and its related CO2 emission in 2021. The contribution of 41.4% of renewable energy as compared to 56.8% of non-renewable energy in the year of 2023 at national level necessities attention of green sources of energy like solar, wind, hydro, waste to energy, small hydropower, etc. Hydropower is one of the reliable backbones of clean energy system which should be used effectively for power generation. The turbine dependent hydropower plant of 45-60 years old requires renovation, modernization, uprating and digitization (RMUD) to resolve socio-economic concerns and increasing demands. This scenario imposes the need of finding solution in existing hydropower plant than investing on new unit. Both high and low discharge should be potentially used for power generation to improve the capacity factor of the plant. Therefore, present work focusses on improving capacity factor of an existing agricultural dependent hydro power plants having reaction type turbine. Reaction turbines operates at high flow and low/medium head conditions. The operational conditions of low flow and low head for reaction turbines may lead to noise, vibration and directed to major catastrophic failure of turbines. There is a need of utilizing the energy potentials balancing power generation and irrigation even during low flow releases. Thus, this paper is an attempt to a design and develop a modified irrigation gate with sliding gate and mini hydropower system at the inlet of existing irrigation diversion gate. Stochastic nature of flows through different hydraulic structures is to be addressed by this modification. A case study of an irrigation dependent hydropower plant Dhom (2X1 MW), MAHAGENCO, Satara, Maharashtra having TWO irrigation gates have been considered. In addition to 2MW, the suggested design can generate 680kW by average irrigation releases of 2.47m3/sec through each gate. The suggested model can be used on any hydropower plant and canal locations.

Development of Patented Autonomous Quantum Gravitational Electric Energy Generator Prototypes

After quantum physics modelling of Gravitational interaction from hypotheses, we performed experimental confirmation experiments of predicted increased Faraday&amp;rsquo;s induction. Brief and low energy electric discharges were made, at room temperature, into partially superconducting Graphite based devices, patented and named &amp;ldquo;emitters&amp;rdquo;, inserted in series with the primary low inductance of a transformer. The high voltage secondary inductance of that transformer was connected to a capacitor, so the secondary current oscillated during several milliseconds.&#x0D; &#x0D; We Measured the global energy efficiency of Faraday&amp;rsquo;s induction, during each electric discharge into the emitter of the primary circuit. We also measured evolution of the peak primary discharge current, and of its derivative, versus the initial charge voltage. We observed systematically a much larger than 100% energy efficiency. That energy efficiency increases with the primary discharge energy. The peak discharge current is observed to be much larger than predicted by Ohm&amp;rsquo;s Law, and the discharge current derivative is also observed to be much larger than classically predicted.&#x0D; &#x0D; Same experiments, performed with &amp;ldquo;normal conductive devices (control)&amp;rdquo;, gave energy efficiencies much lower than 100 %, independent of the stored energy. And their peak discharge currents and derivatives followed Ohm&amp;rsquo;s Law.&#x0D; &#x0D; From these confirmations of predicted results, we proposed and tested successfully concepts of Autonomous electric Generators prototypes, extracting their energy from the cosmological Gravitational quantum field. Their industrial use into electric vehicles should preserve Earth fossil energy resources, as well as reduce the detrimental climate effects of greenhouse gases emissions. Hypotheses are suggested to explain the observed experimental facts.

Determinants of Guideline-Directed Medical Therapy Implementation During Heart Failure Hospitalization

BackgroundDespite evidence that guideline-directed medical therapies (GDMTs) improve outcomes in patients with heart failure (HF) with reduced ejection fraction (HFrEF), implementation remains suboptimal. ObjectivesThe purpose of this study was to measure GDMT implementation during acute HFrEF hospitalization, evaluate the association between socioeconomic factors and GDMT implementation, and assess the association of GDMT utilization with subsequent clinical events. MethodsRetrospective determination of GDMT utilization using a modified optimal medical therapy (mOMT) score (which accounts for specific contraindications to drugs) during unplanned HF hospitalization of consecutive adult patients with new-onset or previously diagnosed HFrEF from 2017 to 2018. Outcomes included discharge mOMT score, association between socioeconomic factors and GDMT implementation (assessed using both the Mann-Whitney U test for binary variables and the Kruskall-Wallace for nonbinary variables), composite outcome 1-year all-cause mortality and 1-year HF readmission, and each component as a function of discharge mOMT score (assessed using univariate and multivariable Cox proportional hazards regression models). ResultsOf 391 patients fulfilling entry criteria (of which 152 [38.9%] had new-onset HFrEF), only 49 (12.5%) had a perfect or near-perfect discharge mOMT score. Black patients and those experiencing homelessness had significantly lower discharge mOMT scores. Higher discharge mOMT score is associated with a lower rate of composite endpoint events, particularly in patients with new-onset HFrEF. Overall, a 0.1-increase in the mOMT score resulted in a 9.2% reduction in the composite endpoint. ConclusionsSuboptimal implementation of GDMT during HF hospitalization is widespread and is associated with a worse outcome. Black patients and patients experiencing homelessness were less likely to have GDMT optimized.

Isotope effects on transport characteristics of edge and core plasmas heated by neutral beam injection (NBI) in an inward shifted configuration at the Large Helical Device

Isotope effects have been investigated in Neutral Beam Injection (NBI) heated plasmas on the Large Helical Device with similar operational parameters between Hydrogen (H) and Deuterium (D) plasmas. Experimental results show that the global energy confinement has no significant dependence on the isotope mass under similar discharge conditions with nearly the same heating power, line-averaged density ( nˉe ) and magnetic field. For both electron and ion energy transport, the transport coefficients, which are obtained based on local power balance analysis, have analogous profiles between H and D dominant plasmas. For neoclassical χe and χi values, they are almost equal between H and D dominant plasmas in low nˉe discharges, whereas in high nˉe cases they are lower in H plasmas than those in D ones. At low nˉe , the electron and ion thermal transport in both H and D plasmas are dominated by neoclassical transport at a certain zone ( ρ≈0.6−0.85 ), while the anomalous transport process has primary effects in the remaining area, and the density fluctuations exhibit ion temperature gradient mode nature. With increase of nˉe , the anomalous transport becomes prevailing and the density fluctuations propagate along electron diamagnetic drift direction. Bispectral analysis reveals that the H plasma has stronger nonlinear coupling in edge density fluctuations in both low and high density discharges, which is probably due to that the D plasma has stronger damping rate for the nonlinear interaction of turbulence. For a comparative study, the present results have been compared with those observed in the ECRH discharges (Tanaka et al 2019 Nucl. Fusion 59 126040). The reasons for the similarities and dissimilarities between these two different heating manners are not clear yet. To unravel the underlying physics, essential inputs from theories and simulations are required.

Path length and sediment transport estimation from DEMs of difference: a signal processing approach

Abstract. The difficulties of measuring bedload transport in gravel-bed rivers have given rise to the morphological method wherein sediment transport can be inferred from changes in riverbed elevation and estimates of the distance traveled by sediment: its path length. Because current methods for estimating path length are time- and labor-intensive, we present a method to estimate a characteristic path length from repeat digital elevation models (DEMs of difference, i.e., DoDs). We propose an automated method to extract the spacing between erosional and depositional sites on the DoD by the application of variational mode decomposition (VMD), a signal processing method, to quantify the spacing as a proxy for path length. We developed this method using flume experiments where bed topography and sediment flux were measured and then applied it to published field data with physical path length measured from tracer measurements. Our sediment transport estimates were not significantly different than the measured sediment flux at lower discharges in the lab. However, we observed an underestimation of sediment flux at the higher discharges in the flume study. We interpret this as a limit of the method in confined settings, where sediment transport becomes decoupled from morphological changes. We also explore how the time between survey acquisitions, the morphological active width relative to the channel width, and DoD thresholding techniques affect the proposed method and the potential issues they pose for the morphological method in general.

River plastic transport affected by tidal dynamics

Abstract. Plastic is an emerging pollutant, and the quantities in rivers and oceans are expected to increase. Rivers are assumed to transport land-based plastic into the ocean, and the fluvial and marine transport processes have been relatively well studied to date. However, the processes controlling the transport in tidal rivers and estuaries, the interface between fluvial and marine systems, remain largely unresolved. For this reason, current estimates of riverine plastic pollution and export into the ocean remain highly uncertain. Hydrodynamics in tidal rivers and estuaries are influenced by tides and freshwater discharge. As a consequence, flow velocity direction and magnitude can change diurnally. In turn, this impacts the transport dynamics of solutes and pollutants, including plastics. Plastic transport dynamics in tidal rivers and estuaries remain understudied, yet the available observations suggest that plastics can be retained here for long time periods, especially during periods of low net discharge. Additional factors such as riparian vegetation and riverbank characteristics, in combination with bi-directional flows and varying water levels, can lead to an even higher likelihood of long-term retention. Here, we provide a first observation-based estimate of net plastic transport on a daily timescale in tidal rivers. For this purpose, we developed a simple Eulerian approach using sub-hourly observations of plastic transport and discharge during full tidal cycles. We applied our method to the highly polluted Saigon River, Vietnam, throughout six full tidal cycles in May 2022. We show that the net plastic transport is about 20 %–33 % of the total plastic transport. We found that plastic transport and river discharge are positively and significantly correlated (Pearson's R2 = 0.76). The net transport of plastic is higher than the net discharge (20 %–33 % and 16 %, respectively), suggesting that plastic transport is governed by factors other than water flow. Such factors include wind, varying plastic concentrations in the water, and entrapment of plastics downstream of the measurement site. The plastic net transport rates alternate between positive (seaward) net transport and negative (landward) net transport as a result of the diurnal inequality in the tidal cycles. We found that soft and neutrally buoyant items had considerably lower net transport rates than rigid and highly buoyant items (10 %–16 % vs. 30 %–38 %), suggesting that transport dynamics strongly depend on item characteristics. Our results demonstrate the crucial role of tidal dynamics and bi-directional flows in plastic transport dynamics. With this paper we emphasize the importance of understanding fundamental transport dynamics in tidal rivers and estuaries to ultimately reduce the uncertainties of plastic emission estimates into the ocean.