Peak Volume Research Articles

A numerical study on the performance of a hybrid ventilation and power generation system

Ventilation, cooling and power are essential requirements of buildings. Integration of solar chimney, earth-air heat exchanger and photovoltaic panel forms a new hybridsystem, which is able to provide simultaneous ventilation, cooling capacity and electricity in an effective manner for buildings. The contribution of this study is to quantitatively identify the thermal and electrical performances of the hybrid system using a comprehensive validated numerical model. In addition, a parametric study was also performed to examine the effect of the number of EAHE pipe and solar collector on the performance of the hybrid system in order to further enhance the system performance. The results revealed that the peak daytime ventilation of the proposed hybrid system is reduced by 22.05 % compared to the ventilation system of solar chimney integrated with earth-air heat exchanger, and the outlet air temperature is reduced by 0.12 °C in average; the indoor temperatures for the hybrid and ventilation systems are slightly different. Moreover, the minimum electrical efficiency of hybrid system is 1.34 % higher than that for stand-alone photovoltaic system. Increasing the number of earth-air heat exchangers leads to more than 36.43 % increase in peak ventilation volume and 3.7 % improvement in electrical efficiency. In addition, increasing the quantity of solar chimney-photovoltaic modules can effectively increase the induced ventilation volume, and the outlet air temperature, but has slight effect on the temperature and electrical efficiency of photovoltaic panel. Therefore, the hybrid system not only can supply appropriate ventilation but also can generate electric power to buildings. The findings provide a preliminary guidance for optimizing design of the hybrid system.

Optimising Flood Risk Reduction in Bali's Provincial Government Center through Cultural Philosophy Approach and GIS-based Conservation of Infiltration Wells

Bali's administrative center, Renon Village, faces an increased risk of flooding due to land cover change. Conservation is needed to reduce this risk by improving water infiltration capacity. Infiltration wells are a solution to increase infiltration capacity. The Tri Hita Karana concept approach, especially Palemahan, in Balinese culture is adopted to implement infiltration well conservation with the support of GIS technology and by flood regulations and infiltration wells. The analysis showed that with a land area of 100 m2, the dimensions of the infiltration well were obtained in diameter of 1 m, and a depth of 2 m with a total of 2 pieces could absorb 2.46 m3 of rainwater. The application of infiltration wells in the study area can reduce the discharge and volume of flood peaks of 2 years, 5 years, 10 years, 25 years, 50 years, 100 years, and 200-year flood peaks, effectively reducing from 8.61% to 31.24%. This research supports the planning of sustainable drainage with a Low Impact Development approach. In addition, the construction of infiltration wells also contributes to preserving water conservation and applying green buildings that are environmentally friendly and energy efficient.

Peak Edema Extension Distance: An Edema Measure Independent from Hematoma Volume Associated with Functional Outcome in Intracerebral Hemorrhage.

Our objective was to test the association between hematoma volume and long-term (> 72h) edema extension distance (EED) evolution and the association between peak EED and early EED increase with functional outcome at 3months in patients with intracerebral hemorrhage (ICH). This retrospective cohort study included patients with spontaneous supratentorial ICH between January 2006 and January 2014. EED, an edema measure defined as the distance between the hematoma border and the outer edema border, was calculated by using absolute hematoma and edema volumes. We used multivariable logistic regression accounting for age, ICH volume, and location and receiver operating characteristic analysis for assessing measures associated with functional outcome and EED evolution. Functional outcome after 3months was assessed by using the modified Rankin Scale (0-3 = favorable, 4-6 = unfavorable). To identify properties associated with peak EED multivariable linear and logistic regression analyses were conducted. A total of 292 patients were included. Median age was 70years (interquartile range [IQR] 62-78), median ICH volume on admission 17.7mL (IQR 7.9-40.2), median peak perihemorrhagic edema (PHE) volume was 37.5mL (IQR 19.1-60.6), median peak EED was 0.67cm (IQR 0.51-0.84) with an early EED increase up to 72h (EED72-0) of 0.06cm (- 0.02 to 0.15). Peak EED was found to be independent of ICH volume (R2 = 0.001, p = 0.6). In multivariable analyses, peak EED (odds ratio 0.224, 95% confidence interval [CI] [0.071-0.705]) and peak PHE volume (odds ratio 0.984 [95% CI 0.973-0.994]) were inversely associated with favorable functional outcome at 3months. Receiver operating characteristic analysis identified a peak PHE volume of 26.8mL (area under the curve 0.695 [95% CI 0.632-0.759]; p ≤ 0.001) and a peak EED of 0.58cm (area under the curve 0.608 [95% CI 0.540-0.676]; p = 0.002) as best predictive values for outcome discrimination. Compared with absolute peak PHE volume, peak EED represents a promising edema measure in patients with ICH that is largely hematoma volume-independent and nevertheless associated with functional outcome.

The testing of a multivariate probabilistic framework for reservoir safety evaluation and flood risks assessment in Slovakia: A study on the Parná and Belá Rivers

Abstract Intense floods represent a challenge to risk management. While they are multivariate in their nature, they are often studied in practice from univariate perspectives. Classical frequency analyses, which establish a relation between the peak flow or volume and the frequency of exceedance, may lead to improper risk estimations and mitigations. Therefore, it is necessary to study floods as multivariate stochastic events having mutually correlated characteristics, such as peak flood flow, corresponding volume and duration. The joint distribution properties of these characteristics play an important role in the assessment of flood risk and reservoir safety evaluation. In addition, the study of flood hydrographs is useful because of the inherent dependencies among their practice-relevant characteristics present on-site and in the regional records. This study aims to provide risk analysts with a consistent multivariate probabilistic framework using a copula-based approach. The framework respects and describes the dependence structures among the flood peaks, volumes, and durations of observed and synthetic control flood hydrographs. The seasonality of flood generation is respected by separate analyses of floods in the summer and winter seasons. A control flood hydrograph is understood as a theoretical/synthetic discharge hydrograph, which is determined by the flood peak with the chosen probability of exceedance, the corresponding volume, and the time duration with the corresponding probability. The framework comprises five steps: 1. Separation of the observed hydrographs, 2. Analysis of the flood characteristics and their dependence, 3. Modelling the marginal distributions, 4. A copula-based approach for modelling joint distributions of the flood peaks, volumes and durations, 5. Construction of synthetic flood hydrographs. The flood risk assessment and reservoir safety evaluation are described by hydrograph analyses and the conditional joint probabilities of the exceedance of the flood volume and duration conditioned on flood peak. The proposed multivariate probabilistic framework was tested and demonstrated based on data from two contrasting catchments in Slovakia. Based on the findings, the study affirms that the trivariate copula-based approach is a practical option for assessing flood risks and for reservoir safety.

Abstract 13447: Political Orientation of Online Media Sources and Reporting of COVID-19 Vaccine Myocarditis

Background: Political orientation has played a role in patients' perceptions of risk associated with COVID-19 vaccination, including COVID-19 vaccine myocarditis (CVM). We examined the relationship between political orientation of popular online media outlets and reporting of CVM. Methods: Media sites were classified as “left” or “right" biased using the Allsides media bias rating report. For each site “COVID vaccine myocarditis” was searched in articles posted 5/21-12/22. Each search return was reviewed for the following: 1) Did it contain numerical data or reference the source of numerical data regarding CVM risk? 2) Did it report benefits of covid vaccination? 3) Did it mention covid infection -related myocarditis? Monthly reports of vaccine-related adverse events were obtained directly from the Vaccine Adverse Events Reporting System (VAERS). Correlations of reports of left- vs. right-leaning media were performed using Pearson Product Moment Correlation. Results: A total of 520 unique online reports regarding CVM were reviewed. Comparison of report volumes from left vs. right biased media sources by month during the assessment period demonstrated modest correlation (r=0.546, p=0.013), suggesting that monthly reporting volumes were driven by availability of information regarding CVM rather than media political alignment. Peak reporting across both left and right biased media was temporally proximate to peak volume of VAERS reporting. Left biased media sources were significantly more likely to include numerical data and/or links to source data vs. right biased sources (76.6% vs. 24.3%, p<0.001) and likewise were more likely to include data supporting benefits of covid vaccination (85.1% vs. 21.7%. p<0.001). In contrast, there was no difference regarding mention of COVID-19 infection-related myocarditis (24.5% vs. 24.3%, p=0.957). Conclusion: Political orientation of online news sites was not associated with frequency of CVM reports but was significantly related to report content, most notably whether reports included numerical vs verbal representations of CVM risk. These bias-related reporting characteristics may contribute to the relationship between political orientation and patient understanding of risk of CVM.

Effects of initial unloading level on the mechanical, micro failure and energy evolution characteristics of stratified rock mass under triaxial unloading confining pressure

In order to study the strength, micro crack distribution and energy evolution characteristics of stratified rock mass under unloading confining pressure conditions, triaxial compression tests and triaxial unloading confining pressure tests at different initial unloading levels were carried out. The experimental results indicated that the triaxial unloading confining pressure plus axial stress is a stress path between the stress state of uniaxial compression and triaxial compression. With the increasing initial unloading level, the specimen is closer to the stress state of triaxial compression, the peak stress, peak axial strain, peak circumferential strain and peak volume strain increase linearly, Poisson’s ratio decreases linearly, failure type of specimens shows 4 typical characteristics. When the bedding plane inclination is 45°, 3D reconstruction and quantitative characterization of micro cracks of stratified rock mass specimens are conducted based on CT scanning results. Variations of area fraction along the specimen height show 3 typical characteristics. The stratified rock mass mainly stores and dissipates energy before the peak stress, and mainly releases and dissipates energy after the peak stress under different conditions. With the increasing initial unloading level, the input energy, elastic energy, dissipative energy and energy dissipation rate at the peak stress increase approximately linearly.

The Onset, Middle, and Climax of Precursory Hydrothermal Intrusion of the 2018 Phreatic Eruption at Kusatsu‐Shirane Volcano

AbstractTriggering intrusions of phreatic eruptions are often observed as seismic and ground deformation signals on a time scale of minutes. The current understanding of hydrothermal intrusions still needs improvement to obtain insight into the eruption scale from the observables. We examine local geophysical data from the precursory hydrothermal intrusion of the 2018 phreatic eruption of Kusatsu‐Shirane volcano. To achieve an integrated intrusion model, we divide analyzing time window into the onset, middle, and climax. Focusing on the transient response of tilt data for the sudden pressurization, we estimate a vertical tensile opening (1.7 × 103 m3/s in 40 s) at 1.1 km depth for the intrusion onset. Pressurization can represent the start of vapourization. Very long period (VLP, 0.033–0.1 Hz) seismic signals are adopted to constrain the middle and climax phases. We obtained two sequential semi‐horizontal tensile crack oscillation sources with peak volume changes of 3.6 × 104–1.9 × 105 m3 at 0.3–0.6 km depths. The second VLP source acted as a final trigger of the eruption to cause depressurization in the shallow portion of the intruded region, which is constrained as having reached 0.1 km depth by surface deformation. Simultaneously, we find another depressurization originated from depth in the climax due to a decrease in the hydrothermal intrusion rate. Through comparison with the 2014 Ontake phreatic eruption, the total inflation volume may correlate with eruption scales. Intruded hydrothermal fluid and local structure characteristics also may have to be considered to evaluate the eruptions scales from inferred signal source intensity.

Hamstring harvest results in significantly reduced knee muscular protection during side-step cutting two years after anterior cruciate ligament reconstruction.

The purpose of this study was to determine the effect of donor muscle morphology following tendon harvest in anterior cruciate ligament (ACL) reconstruction on muscular support of the tibiofemoral joint during sidestep cutting. Magnetic resonance imaging (MRI) was used to measure peak cross-sectional area (CSA) and volume of the semitendinosus (ST) and gracilis (GR) muscles and tendons (bilaterally) in 18 individuals following ACL reconstruction. Participants performed sidestep cutting tasks in a biomechanics laboratory during which lower-limb electromyography, ground reaction loads, whole-body motions were recorded. An EMG driven neuro-musculoskeletal model was subsequently used to determine force from 34 musculotendinous units of the lower limb and the contribution of the ST and GR to muscular support of the tibiofemoral joint based on a normal muscle-tendon model (Standard model). Then, differences in peak CSA and volume between the ipsilateral/contralateral ST and GR were used to adjust their muscle-tendon parameters in the model followed by a recalibration to determine muscle force for 34 musculotendinous units (Adjusted model). The combined contribution of the donor muscles to muscular support about the medial and lateral compartments were reduced by 52% and 42%, respectively, in the adjusted compared to standard model. While the semimembranosus (SM) increased its contribution to muscular stabilisation about the medial and lateral compartment by 23% and 30%, respectively. This computer simulation study demonstrated the muscles harvested for ACL reconstruction reduced their support of the tibiofemoral joint during sidestep cutting, while the SM may have the potential to partially offset these reductions. This suggests donor muscle impairment could be a factor that contributes to ipsilateral re-injury rates to the ACL following return to sport.

Criteria to Evaluate Tumor Enlargement During the Active Surveillance of High-Risk Thyroid Nodules: Which is Better, Diameter or Volume?

Tumor enlargement is the most common parameter identifying disease progression during active surveillance, but the value and significance of the changes in tumor diameter and volume in the evaluation of tumor growth have not been compared. This cohort study included 468 patients with high-risk thyroid nodule, in whom nodule size change was monitored using ultrasound, to compare the changes in tumor diameter and volume in assessing tumor growth. A total of 569 high-risk thyroid nodules were found in the 468 patients. A total of 14 nodules (2.5%) showed a diameter increase ≥ 3mm. The number of nodules with a peak volume change exceeding 50% and 100% was 185 (32.5%) and 86 (15.1%), respectively. Among the 555 stable nodules, the number of nodules with volume fluctuations exceeding 50% and 100% was 171 (30.8%) and 72 (13.0%), respectively. Among 212 stable nodules at the baseline and in the first three follow-up, the percentage of peak volume fluctuations exceeding 50% (48.5% vs. 28.5%, p = 0.004) and 100% (26.5% vs. 8.3%, p < 0.001) in the nodules with the sum of three diameters (SOTDs) ≤ 1cm was significantly higher than that of nodules with SOTDs > 1cm. A statistically significant difference was also found in the range distribution of SOTDs ≤ 1cm and SOTDs > 1cm (p = 0.007). Volume is not an appropriate method for determining tumor growth. Tumor diameter measurement alone serves as a better surrogate for disease progression in sonographically high-risk thyroid nodules than volume.

Brain Growth Charts for Quantitative Analysis of Pediatric Clinical Brain MRI Scans with Limited Imaging Pathology.

Background Clinically acquired brain MRI scans represent a valuable but underused resource for investigating neurodevelopment due to their technical heterogeneity and lack of appropriate controls. These barriers have curtailed retrospective studies of clinical brain MRI scans compared with more costly prospectively acquired research-quality brain MRI scans. Purpose To provide a benchmark for neuroanatomic variability in clinically acquired brain MRI scans with limited imaging pathology (SLIPs) and to evaluate if growth charts from curated clinical MRI scans differed from research-quality MRI scans or were influenced by clinical indication for the scan. Materials and Methods In this secondary analysis of preexisting data, clinical brain MRI SLIPs from an urban pediatric health care system (individuals aged ≤22 years) were scanned across nine 3.0-T MRI scanners. The curation process included manual review of signed radiology reports and automated and manual quality review of images without gross pathology. Global and regional volumetric imaging phenotypes were measured using two image segmentation pipelines, and clinical brain growth charts were quantitatively compared with charts derived from a large set of research controls in the same age range by means of Pearson correlation and age at peak volume. Results The curated clinical data set included 532 patients (277 male; median age, 10 years [IQR, 5-14 years]; age range, 28 days after birth to 22 years) scanned between 2005 and 2020. Clinical brain growth charts were highly correlated with growth charts derived from research data sets (22 studies, 8346 individuals [4947 male]; age range, 152 days after birth to 22 years) in terms of normative developmental trajectories predicted by the models (median r = 0.979). Conclusion The clinical indication of the scans did not significantly bias the output of clinical brain charts. Brain growth charts derived from clinical controls with limited imaging pathology were highly correlated with brain charts from research controls, suggesting the potential of curated clinical MRI scans to supplement research data sets. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Ertl-Wagner and Pai in this issue.

Spatio-temporal characteristics of human activities using location big data in Qilian Mountain National Park

ABSTRACT Human activities significantly impact the environment. Understanding the patterns and distribution of these activities is crucial for ecological protection. With location-based technology advancement, big data such as location and trajectory data can be used to analyze human activities on finer temporal and spatial scales than traditional remote sensing data. In this study, Qilian Mountain National Park (QMNP) was chosen as the research area, and Tencent location data were used to construct time series data. Time series clustering and decomposition were performed, and the spatio-temporal distribution characteristics of human activities in the study area were analyzed in conjunction with GPS trajectory data and land use data. The study found two distinct human activity patterns, Pattern A and Pattern B, in QMNP. Compared to Pattern B, Pattern A had a higher volume of location data and clear nighttime peaks. By incorporating land use and trajectory data, we conclude that Pattern A and Pattern B represent the activity patterns of the resident and tourist populations, respectively. Moreover, the study identified seasonal variations in human activities, with human activity in summer being approximately two hours longer than in winter. We also conducted an analysis of human activities in different counties within the study area.

Optimizing Catalyst Layer Structure with Carbon Nanofiber Additive for Better Performance of Proton Exchange Membrane Fuel Cell

Increasing the power density of proton exchange membrane fuel cell (PEMFC) is essential for its commercialization. Cathode catalyst layer (CCL) carbon additive is an effective method that can improve membrane electrode assembly (MEA) performance under high current density. In this work, carbon nanofiber (CNF) is used as CCL additive and its mechanism is studied. The influence of CNF on the CCL structure is studied by scanning electron microscope (SEM), nitrogen adsorption method and contact angle experiment. Meanwhile, the mechanism is examined by using polarization decomposition and impedance analysis combined with the result in characterization experiments. The results show that: (1) the MEA used in this work has the best performance when adding 1 wt%. The voltage rises 74 mV (15.42%) at 2 A cm−2; (2) CNF varies the MEA performance mainly through changing the hydrophobicity of CCL, influencing the mass transport resistance and the concentration polarization. The mass transport resistance decreases 57.18% at 2 A cm−2; (3) activation polarization values have a negative linear correlation with the peak volume values of the primary pores at around 4 nm in diameter. This study provided a detailed understanding of the mechanism of CNF additive in CCL and will be helpful for improving PEMFC performance.

Cardiopulmonary exercise testing criteria for advanced therapies in patients with heart failure.

Many cardiology associations endorse the role of the cardiopulmonary exercise test (CPET) to define the severity of impairment of functional capacity in individuals with heart failure with reduced ejection fraction (HFrEF) and when evaluating the need for advanced therapies for these patients. The focus of the CPET within the cardiology community has been on peak volume of oxygen uptake (VO2). However, several CPET variables are associated with outcomes in individuals with and without chronic disease and can inform clinical decisions in individuals with HFrEF. In this manuscript, we will review the normal cardiopulmonary response to a graded exercise test and review current guideline recommendations relative to CPET in patients with HFrEF.

The geochronometry of Idaho and the bumpy barcode revisited: Snake River detrital zircons in Hells Canyon and beyond

Detrital zircons in modern stream sands and terraces of the Snake River drainage upstream of and within Hells Canyon, western Idaho, U.S.A, effectively reproduce the geochronometry of Idaho magmatic rocks, both from Laurentia in eastern Idaho, and from the accreted terranes west of the Salmon River Suture. We used large-n (300 grain) analysis of detrital zircon ages and Monte Carlo-based mixture modeling to estimate the percent contributions from the upper Snake River and several tributaries. The large number of grains analyzed allows more precise statistical modeling than previous studies, which used 60 or 100 grains.Immediately upstream of the Hells Canyon Complex of dams modeling suggests that the Snake River at Farewell Bend contains detrital zircon contributions of Payette River 50 % and Boise River 10 % (mainly from the Atlanta lobe, Idaho batholith). The upper Snake River has 30 % contribution and contains a complex detrital zircon signature including both primary zircons derived from magmatic sources and recycled zircons derived from sedimentary rocks with an ultimate magmatic source. Thus, 60 % of the detrital zircons come from the 98–73 Ma southern Idaho batholith, with less than a third coming from the upper Snake River drainage, despite it representing 60 % of the drainage area. The Owyhee, Malheur, and Weiser rivers contribute <5 % each.Within Hells Canyon, modeling suggests that the main Snake River contributes by far the largest component (85 %); side canyons contribute <5 % of the zircon load. Mixing models for Snake River stream sediment downstream of Lewiston, below Lower Granite Dam (sampled from sands deposited before installation of the dam), suggest 53 % contribution from the main Snake River above the Salmon River, 34 % from the Clearwater River, 7 % from the Salmon River, and 6 % from the Grande Ronde River.Comparing relative zircon inputs from the modern Snake and Salmon rivers to a pre-dam river terrace just downstream from their confluence suggests that the Snake River in Hells Canyon today contributes only 4 % of the detrital zircons whereas before installation of the Hells Canyon Dams it contributed 29 %. We interpret this reduction in detrital zircon supply to be caused by sediment trapping above the dams.One influence on the detrital zircon contribution of various streams is peak flow volume. Zircon fertility of specific source rocks is the main influence on detrital zircon percentages within individual drainages. Mesoproterozoic, Cretaceous and Eocene granitic rocks produce euhedral magmatic detrital zircon grains that dominate several drainages. Mesozoic metavolcanic and Eocene Challis Volcanic Group rocks yield fewer and often broken detrital zircon grains. Large outcrop areas of Neogene Columbia River and Snake River Plain basalts provide almost none. Recycling of older magmatic detrital zircon through Proterozoic and Paleozoic sandstones is a signature of the eastern and central Idaho thrust belt.

Perihematomal edema after minimally invasive surgery: a matter of concern to neurosurgeons.

The purpose of this study is to explore the evolution of brain edema after minimally invasive surgery in deep spontaneous cerebral hemorrhage (DSICH) treatment and to analyze the differences in edema after different surgical methods. The clinical data of 105 patients with DSICH treated at Renmin Hospital of Wuhan University from January 2020 to June 2022 were analyzed retrospectively. Among them, 54 patients were treated with minimally invasive puncture and drainage surgery (MIPDS group), and 51 were treated with neuroendoscopic surgery (NES group). Continuous computed tomography images of patients in the hospital and 3D Slicer software were used to quantitatively calculate the edematous area to explore the changes in perihematomal edema volume in the two groups after the operation. The peak volume of postoperative edema (37.36±10.51 mL) in the MIPDS group was more extensive than that in the NES group, and its net increase in edema volume was 16.86±10.01 mL more than that in the NES group. The relative edema index (0.86±0.26) was lower in the NES group than in the MIPDS group (P < 0.05). The peak of postoperative edema in the MIPDS group was at 6-8 days after the operation, and that in the NES group was most often at 3-5 days after the operation. There are differences in perihematomal edema of DSICH treated by different minimally invasive methods. Compared with the MIPDS group, the NES group showed earlier peak of cerebral edema and lower degree of cerebral edema. The absolute regression volume of edema in the MIDPs group was greater than that in the NEs group, but there was no difference in the regression rate of edema between the two groups.

The Value of Stress-Gated Blood Pool SPECT in Predicting Early Postoperative Period Complications in Ischemic Cardiomyopathy Patients: Focus on Mechanical Dyssynchrony.

(1) Objective: The objective of this study was to assess the prognostic value of stress-gated blood pool SPECT (GBPS) estimates in patients with ischemic cardiomyopathy (ICM) in the early postoperative period. (2) Methods: A total of 57 patients (age 59.7 ± 6.6, 47 men) with ICM and LV ejection fraction (30 [27.5; 35]%) were enrolled in the study. Before surgical treatment, all patients underwent GBPS (rest-stress, dobutamine doses of 5/10/15 µg/kg/min). Stress-induced changes in left ventricular (LV) ejection fraction, peak ejection rate, volumes, and mechanical dyssynchrony (phase histogram standard deviation, phase entropy (PE), and phase histogram bandwidth) were estimated. Two-dimensional transthoracic echocardiography was performed baseline. Serum levels of NT-proBNP were analyzed with enzyme-linked immunoassay. (3) Results: After surgical treatment, patients were divided into two groups, one, with death, the need for an intra-aortic balloon pump (IABP) or/and inotropic support with a stay in the intensive care unit for more than two days and two, without complications in the early postoperative period (EPOP). Complicated EPOP (CEPOP) was observed in 17 (30%) patients (death-2, IABP-4, extra inotropic support in intensive care unit-11), and 40 patients had no complications (NCEPOP). GBPS showed differences in LV EDV (mL) (321 [268; 358] vs. 268 [242; 313], p = 0.02), LV ESV (mL) (242 [201; 282] vs. 196 [170; 230], p = 0.005), and stress-induced changes in PE (1 (-2; 3) vs. -2 (-4; 0), p = 0.02). Aortic cross-clamp time and stress-induced changes in PE between rest and dobutamine dose of 10 µg/kg/min were the only independent predictors of CEPOP. An increase in LV entropy ≥ 1 on the dobutamine dose of 10µg/kg/min in comparison to rest investigation showed AUC = 0.853 (sensitivity = 62%, specificity = 90%, PPV = 71%; NPV = 85%; p < 0.0001). Conclusion: Stress-induced changes in PE obtained during low-dose dobutamine GBPS are associated with a complicated course of the early postoperative period after surgical treatment for ICM.

Spatial Distributions of Cloud Occurrences in Terms of Volume Fraction as Inferred from CloudSat and CALIPSO

The cloud amount, referred to as the frequency of cloud occurrences, is of great importance for the Earth–atmosphere system. It was conventionally quantified as the area fraction of clouds in a given region, discarding the three-dimensional nature of both cloud entities and their spatial distribution. Although the area fraction is explicit, it is the volume fraction that fully depicts cloud occurrences, and the area fraction is just related to a projection of the volume fraction. In this study, by using spaceborne radar measurements, the spatial distribution of cloud volume fraction throughout the troposphere was investigated, and the contributions of various cloud types at each location were clarified. Overall, the volume fraction of total clouds in the whole troposphere is 15.9%, while the corresponding area fraction relative to the global surface is 73.6%. The peak volume fraction occurs at 1 km altitude, mainly contributed by stratocumulus and cumulus. For a single cloud type, the maximum fraction is 48.8%, which is from stratocumulus and occurs at 1 km altitude above the Greenland Sea. Half of the eight cloud types, altostratus, cirrus, nimbostratus, and deep convective clouds, reach the nominal tropopause. In particular, the vertical distribution difference among multiple cloud types in each category (low-level, middle-level, and vertically extending) was clarified, and it was found that the dominant cloud type in a category varies notably with the location in the atmosphere.

Comparative pharmacokinetics and tissue distribution of polydatin, resveratrol, and emodin after oral administration of Huzhang and Huzhang-Guizhi herb-pair extracts to rats

Ethnopharmacological relevanceHuzhang-Guizhi herb pair (HGHP), composed of Polygonum cuspidatum (Huzhang [HZ] in Chinese, the root of Polygonum cuspidatum Sieb. & Zucc.) and Ramulus Cinnamomi (Guizhi [GZ] in Chinese, the dried twig of Cinnamomum cassia Presl.), is a popular herb pair commonly used to treat arthritis and involved in many Chinese prescriptions. In order to reveal the influence of GZ on HZ on bioavailability, the pharmacokinetic behaviors and tissue distribution variations of the three analytes from HZ were detected between oral administration of HZ and HGHP extracts to rats. Materials and methodsMale Sprague-Dawley rats were randomly assigned to two groups for pharmacokinetics study and eight groups for tissues distribution research with the equivalent dose of 18 g crude HZ/kg. Assays for analytes from HZ (polydatin, resveratrol, emodin) were developed and validated using high performance liquid chromatography with ultraviolet detection (HPLC-UV). ResultsPart pharmacokinetic parameters including area under the concentration-time curve (AUC), the maximum plasma concentration (Cmax), biological half-life (t1/2), mean residence time (MRT), time to peak concentration (Tmax), clearance rate/bioavailability (CL/F) and volume of distribution/bioavailability (Vd/F) showed significant difference (P < 0.05) after oral administration of HGHP, as compared to those of HZ. The three analytes could be detected in heart, liver, spleen, lung, kidney and brain. Compared with the HZ group, AUC0-t of polydatin in heart, liver and kidney increased significantly (p < 0.05) while that in spleen decreased significantly (p < 0.05); AUC0-t of resveratrol in all detected tissues increased conspicuously (p < 0.05) in the HGHP group; AUC0-t of emodin in heart, liver, spleen, lung, and kidney increased conspicuously (p < 0.05), and decreased obviously (p < 0.05) in brain in the HGHP group. ConclusionsGZ could strongly influence the pharmacokinetic parameters and tissue distribution characteristics of polydatin, resveratrol and emodin in rats when administrated with HZ or HGHP extracts. It might provide a reference for further explanation of the compatibility mechanism and the clinical application of HGHP.

An integrated modeling approach to evaluate the impacts of nature-based solutions of flood mitigation across a small watershed in the southeast United States

Abstract. Floods are among the most destructive natural hazards in the world, posing numerous risks to societies and economies globally. Accurately understanding and modeling floods driven by extreme rainfall events has long been a challenging task in the domains of hydrologic science and engineering. Unusual catchment responses to flooding cause great difficulty in predicting the variability and magnitude of floods, as well as proposing solutions to manage large volumes of overland flow. The usage of nature-based solutions (NBSs) has proved to be effective in the mitigation of flood peak rate and volume in urban or coastal areas, yet it is still not widely implemented due to limited knowledge and testing compared to traditional engineering solutions. This research examined an integrated hydrological and hydraulic modeling system to understand the response of an at-risk watershed system to flooding and evaluate the efficacy of NBS measures. Using the Hydrologic Engineering Center Hydrologic Modeling System and River Analysis System (HEC-HMS and HEC-RAS) software, an integrated hydrologic–hydraulic model was developed for Hurricane Matthew- (2016) and Florence-driven (2018) floods across the Little Pee Dee–Lumber River watershed, North and South Carolina (the Carolinas), US. The focus was on Nichols, a small town that has disproportionately been impacted by flooding during these two hurricane events. The present article proposes a methodology for selecting, modeling, and evaluating the performance of NBS measures within a catchment, which can be extended to other case studies. Different NBS measures, including flood storage ponds, riparian reforestation, and afforestation in croplands, were designed, modeled, and evaluated. Hurricane Matthew's flooding event was used for evaluating the NBS scenarios given its high simulation accuracy in flood inundation compared to the less accurate results obtained for Hurricane Florence. The scenario comparison evidenced that large-scale natural interventions, such as afforestation in croplands, can reduce the inundated area in Nichols by 8 % to 18 %. On the contrary, the smaller-scale interventions such as riparian reforestation and flood storage ponds showed a negligible effect of only 1 % on flood mitigation.

Can the combining of wetlands with reservoir operation reduce the risk of future floods and droughts?

Abstract. Wetlands and reservoirs are important water flow and storage regulators in a river basin; therefore, they can play a crucial role in mitigating flood and hydrological drought risks. Despite the advancement of river basin theory and modeling, our knowledge is still limited about the extent to which these two regulators could perform such a role, especially under future climate extremes. To improve our understanding, we first coupled wetlands and reservoir operations into a semi-spatially explicit hydrological model and then applied it in a case study involving a large river basin in northeast China. The projection of future floods and hydrological droughts was performed using the hydrological model during different periods (near future: 2026–2050, middle century: 2051–2075, and end century: 2076–2100) under five future climate change scenarios. We found that the risk of future floods and hydrological droughts can vary across different periods – in particular, it will experience relatively large increases and slight decreases. This large river basin will experience flood events of longer duration, with larger peak flows and volume, and of enhanced flashiness compared to the historical period. Simultaneously, the hydrological droughts will be much more frequent, with longer durations and more serious deficits. Therefore, the risk of floods and droughts will, overall, increase further under future climate change even under the combined influence of reservoirs and wetlands. These findings highlight the hydrological regulation function of wetlands and reservoirs and attest that the combining of wetlands with reservoir operation cannot fully eliminate the increasing future flood and drought risks. To improve a river basin's resilience to the risks of future climate change, we argue that the implementation of wetland restoration and the development of accurate forecasting systems for effective reservoir operation are of great importance. Furthermore, this study demonstrated a wetland–reservoir integrated modeling and assessment framework that is conducive to risk assessment of floods and hydrological droughts and that can be used for other river basins in the world.