Volume Curves Research Articles

Influences of interface bonding behavior on the arresting performance of CFRP buckle arrestors - Part I: Experiments

CFRP can effectively serve as buckle arrestors for subsea pipelines in virtue of the advantages of lightweight, high strength, and corrosion resistance. In this paper, the interface bonding tests were firstly carried out to assess the bonding performance between the CFRP and pipelines. Three types of tests were designed to evaluate the circumferential, axial, and radial bonding properties, respectively, covering the double-strap joint shear test, axial tensile test, and normal tensile test. The stress-bonding slip responses were measured and various failure modes were identified. The effect of CFRP thickness, type of adhesive, adhesive thickness, and interface roughness on the interface bonding property was explored. Subsequently, SS304 pipe specimens wrapped with CFRP buckle arrestors were tested in a hyperbaric vessel. The pressure-variation in volume curves were obtained, and the flattening and U-shape modes were observed. The influences of adhesive type, adhesive thickness, interface roughness, number of CFRP layers, CFRP thickness, and CFRP length on the crossover pressure were examined. The results demonstrate that the number of CFRP layers and CFRP thickness remarkably affect the arresting performance of CFRP arrestors, and the influence of interface bonding properties on the arresting ability is not as significant as the adhesive strength.

Adaptive stereotactic radiosurgery for cerebral metastases of non-small cell lung cancer: a retrospective study

INTRODUCTION: Non-small cell lung cancer (NSCLC) is a common cause of brain metastases (BM). Adaptive stereotactic radiosurgery (ASRS) may be a useful option in the treatment of patients with large unresectable brain metastases (BM), but to date there are only a limited number of studies evaluating the effectiveness of this method.OBJECTIVE: To analyze the effectiveness of ASRS in patients with large BM NSCLC not subject to surgical resection.MATERIAL AND METHODS: We retrospectively analyzed data from 37 patients suffering from NSCLC with 45 large (>2 cm in diameter, volume >4 cm3) unresectable BM treated with the Gamma Knife Perfexion model using two- and three-fraction ASRS. Of these, 14 foci (31.1%) were metastases of squamous cell lung cancer, 31 (68.9%) were metastases of adenocarcinoma. The median volume of lesions treated with ASRS was 9.8 (range 4.6–30.6 cm3). The dynamics of volume changes between fractions and the cumulative incidence of local relapses (CILR) were studied, and ROC analysis was performed for the tumor volume parameter. Intracranial progression-free survival (iPFS) and overall survival (OS) were assessed. Statistics: To establish statistical significance of differences for related variables, the Wilcoxon test for pairwise comparisons and the Friedman test for three or more groups were used. The Kaplan-Meier method was used to calculate local control, PFS, and OS rates. The log-rank test was used to compare survival data in two groups.RESULTS: The median follow-up period was 19.4 months. With two-fraction ASRS, the median volume of metastasis decreased by 28.6% by the second session, with three-fraction — by 40.0% by the third session. The 1-year and 2-year CILR rates were 8.6±6.1%, respectively; 26.1±12.3%. In ROC analysis, the area under the curve (AUC) for tumor volume was 0.80 (95% CI 0.6– 1.0) with an optimal cutoff of 18.5 cm3. The differences in CILR between the groups with metastasis volume <18.5 cm3 and ≥18.5 cm3 were statistically significant (p<0.001). Median iPFS was 8.3 (95% CI 5.9–10.7) months, 1-year iPFS was 33.5±8.1%;2-year — 7.8±5.2%. Median OS was 13.2 (95% CI 9.0–17.4) months; 1-year OS — 52.9±8.7%, 2-year — 22.4±8.8%.DISCUSSION: Using two- and three-fraction ASRS, we delivered doses to large BM sufficient for a high level of local control with an acceptable risk of neurotoxicity: 1-year local control was 91.4%; 2-year — 73.9%; the incidence of radionecrosis is 8.5%. A statistically significant effect of lesion volume ≥18.5 cm3 on the risk of local recurrence was found. The iPFS and OS indicators after ASRS can be considered satisfactory for this group of patients.CONCLUSION: ASRS is an effective and perhaps optimal strategy for the treatment of large unresectable BM in patients with NSCLC, but comparison with other modern radiotherapy modalities such as stereotactic hypofractionated radiotherapy and WBRT with simultaneous integrated boost is needed.

Drought response strategies of vascular epiphytes in isolated pasture trees in a Costa Rican tropical montane landscape.

Vascular epiphytes of tropical montane cloud forests are vulnerable to climate change, particularly as cloud bases elevate and reduce atmospheric inputs to the system. However, studies have generally focused on epiphytes in contiguous forests, with little research being done on epiphytes on isolated pasture trees. We investigated water relations of pasture-tree epiphytes at three sites located below and above the elevation of the average cloud base in Monteverde, Costa Rica. We measured sap velocity and four microclimate variables in both the dry and wet season of 2018. We also measured functional traits, including pressure volume (PV) curves, predawn/midday water potential, and various lab-based water relations traits. We used linear mixed models to assess the correlation between microclimate and sap velocity in both seasons and ANOVA to assess the variation in PV curve and water potential variables. The turgor loss point generally increased from the wettest to driest site. However, this trend was driven primarily by the increasing prevalence of leaf succulence at drier sites. Microclimatic variables correlated strongly with sap velocity in the wet season, but low soil moisture availability caused this correlation to break down during the dry season. Our results emphasize the vulnerability of cloud forest epiphytes to rising cloud bases. This vulnerability may be more severe in pasture trees that lack the potential buffer of surrounding forest, but additional research that directly compares the canopy microclimate conditions between forest and pasture trees is needed to confirm this possibility.

Estimation of Systolic and Diastolic Left Ventricular Blood Flow From Derivatives of Transesophageal Echocardiographic 3D Volume Curves in Cardiac Surgery Patients: A Proof-of-Concept Study

Estimation of Systolic and Diastolic Left Ventricular Blood Flow From Derivatives of Transesophageal Echocardiographic 3D Volume Curves in Cardiac Surgery Patients: A Proof-of-Concept Study

Robotic-assisted versus laparoscopic-assisted extended mesorectal excision: a comprehensive meta-analysis and systematic review of perioperative and long-term outcomes.

Concurrent neoadjuvant chemo-radiation (nCRT) with total mesorectal excision (TME) alone sometimes fails to cure lateral lymph node metastasis (LLNM). Therefore, additional lateral lymph node dissection (LLND) can help in the treatment of these patients. This is what we refer to as extended total mesorectal excision (eTME). Such operations (TME alone or eTME) can be performed using conventional laparoscopic techniques and robotic-assisted techniques as well. Our meta-analysis aims to compare the results of robot-assisted (R-eTME) versus laparoscopic-assisted extended mesorectal excision (L-eTME) in terms of short- and long-term outcomes. Databases searched using title and abstract included Medline (via PubMed), Web of Science, Scopus, and Embase, up to February 20, 2024. All studies that documented robotic versus laparoscopic procedures for extended total mesorectal excision (R-eTME versus L-eTME) and reported more than two relevant outcomes, were included in the study. Our meta-analysis demonstrates four significant outcomes (operative time, urinary complications, overall recurrence, and admission days) between the laparoscopic and robotic groups. The robotic approach shows advantages over the laparoscopic approach in these outcomes except for the operative time (minute), which was longer in the robotic group compared to the laparoscopic group. The laparoscopic group is associated with a higher overall recurrence than the robotic group with an Odds Ratio of 2(95% CI, 1-4, p = 0.05). This meta-analysis study showed that the R-eTME group had a lower recurrence rate compared to the L-eTME group. Additionally, hospital admission days increased significantly in the laparoscopic group. Other long-term outcomes did not differ significantly between the two groups. Short-term outcomes were similar, except for more urinary complications in the laparoscopic group. In conclusion, the study suggests that robotic surgery may offer advantages over laparoscopic surgery for eTME. Further research and analysis could provide further insight into the potential benefits of robotic surgery in this procedure, particularly when surgeon experience, center volume, and learning curve are taken into consideration.

Evaluation of proudP: A sound-based approach to uroflowmetry.

We sought to assess the performance of the proudP AI algorithm, integrated into a mobile application, in estimating uroflow curves and parameters using recorded urination sounds. A direct comparison was made between the peak flow rate (Qmax), voided volume, and uroflow curves predicted by the proudP algorithm and those obtained through established validation methods. A hardware uroflow simulator replicated uroflow profiles by precisely controlling water flow rates and extracting corresponding sound data. Ten uroflow profiles, representing typical patterns observed in male subjects, were selected. Simulation experiments with proudP were conducted using a standard toilet setup. The uroflow simulator was calibrated to reproduce uroflow profiles, and validation was performed against a Flowmaster uroflowmetry device. Statistical analysis included descriptive summaries, Bland-Altman analysis, and Concordance Correlation Coefficient (CCC) analysis. The proudP accurately captured various uroflow patterns generated by the simulator, with low standard deviations in Qmax predictions and biases near zero. The SDs of voided volume were slightly larger, primarily due to uroflow patterns with extended voiding times. The study validated the accuracy of proudP against in-office uroflowmetry, demonstrating robustness across different smartphone models. proudP proved to be as accurate as in-office uroflowmetry in estimating uroflow rate across various patterns. Its convenience in home monitoring offers patients a means to observe their urination patterns accurately, while enabling healthcare professionals to gain detailed insights remotely. proudP emerges as an essential solution for clinical practice and urological research.

First-Principles insights to probe structural and opto-electronic properties of [formula omitted] (Y=Mg, Sr) halide perovskites with variety of DFT methods

This study reports the structural, electronic, optical, phonon, thermodynamic and thermoelectric properties of AgYF3 (X=Mg, Sr) for photovoltaic and energy applications. We performed first principles calculations using full potential linearized augmented plane wave, FP-LAPW method implemented in Wien2k. The generalized gradient approximations of Perdew–Burke–Ernzerhof PBE-GGA, and PBE revised for solids, PBEsol, is employed for structural optimization of these lead free halide perovskites. The Birch–Murnaghan energy volume curve fitting comprehend the structural stability. The optimized lattice constant of AgMgF3 and AgSrF3 obtained with PBE-GGA(PBEsol) is 3.99(3.92)Å and 4.42(4.65)Å. The stability is further tested with the help of formation energy and positive phonon dispersion curves calculations. For the calculations of explicit electronic and optical properties, we also employed Tran–Blaha modified Beck–Johnson (TB-mBJ) and Strongly Constrained but Appropriately Normed, SCAN, exchange and correlations functionals. The electronic band gap of AgMgF3 computed with PBEsol, TB-mBJ and SCAN is 1.96 eV, 5.25 eV and 2.59 eV exhibiting M-Γ indirect band gap. The band gap energy of AgSrF3 is 2.06 eV, 6.42 eV and 2.70 eV with PBEsol, TB-mBJ and SCAN. The indirect band gap nature of AgSrF3 is confirmed by PBEsol and TB-mBJ while it anticipated direct band gap behavior with meta-GGA SCAN. The different optical parameters like dielectric constant, optical conductivity, energy loss function, absorption, reflectivity and refractive index are calculated to assess optical activity of both perovskites. Comprehensive electronic and optical analysis advocates the utility of AgMgF3 and AgSrF3 for different applications is solar technology and optoelectronic devices.

Exploring mesophase formation: Structural characterization approaches in a soft sphere model

This study employs Molecular Dynamics simulations to enhance the structural characterization of sphere mixture systems, focusing on local order parameters to identify order-disorder transitions within lamellar and hexagonal mesophases. The structural characterization included the use of neural networks and the search for clusters with topological order. We have identified the order-disorder transition at a characteristic temperature TOD, effectively captured by the structural parameters analyzed. Below TOD, the system organizes into an ordered mesophase, while above this temperature, it transitions into an isotropic liquid state. Moreover, within the isotropic region, we observe that the liquid begins to form clusters. This clustering phenomenon becomes evident below a specific temperature, denoted as T⁎. At T⁎, there are noticeable changes in the volume versus temperature curves, indicating a process of micellization or clustering in the system. The structural parameters used in our study also register this behavioral change at T⁎, further supporting the occurrence of this phenomenon. Additionally, our analysis of the overlap in detecting ordered particles between the two structural parameters using the Sørensen-Dice similarity coefficient reveals a significant spatial correlation in the isotropic phase, with a correlation higher than what would be expected in a random case. This indicates that both neural networks and topological cluster classification detect statistically similar ordered regions in the isotropic phase, highlighting the clustering. Our findings reveal that the structural parameters effectively capture both the order-disorder transition at TOD and the clustering process at T⁎. These results provide valuable insights into the self-assembly mechanisms and phase behavior in this soft-sphere model, advancing our understanding of self-assembly processes in material science, particularly in exploring phase behavior in mesogenic nanoparticle systems.

Oscillometry Reference Values for Children and Adolescents

BackgroundOscillometry devices allow quantification of respiratory function at tidal breathing but device-specific reference equations are scarce: the present study aims to create sex-specific oscillometric reference values for children and adolescents using the Resmon PRO FULL device.MethodsHealthy participants (N=981) aged 6 to 17 years of the Austrian LEAD general population cohort were included. Subjects had normal weight (BMI≤99th percentile) and normal lung volumes (total lung capacity (TLC)≥lower limit of normal). Oscillometry data were collected using a single frequency mode of 8 Hz. Sex-specific prediction equations were developed for total (tot), inspiratory (insp) and expiratory (exp) resistance (R) and reactance (X) as well as for the modulus of impedance (Z) value using the LMS (lambda, mu, sigma) method. Height was used as a single covariate.ResultsReference equations for all oscillometry parameters were created for Caucasian children aged 6 to 17 years with a height span from 101 to 183 cm and a lung volume span from 1.7 L to 8.8 L TLC. R and Z values progressively decrease and X values increase with increasing height. Oscillometry parametersversuslung volume curves differ from thoseversusheight curves. Stratified for lung size, no sex differences are found for oscillometry parameters.ConclusionOur study provides reference values for oscillometry parameters in children and adolescents using strictly defined criteria for weight and lung volumes. No sex related differences in oscillometry parameters corrected for height or lung size are found.

Prognostic Implication of Ventricular Volumetry in Early Brain Computed Tomography after Cardiac Arrest.

Brain swelling after cardiac arrest may affect brain ventricular volume. This study aimed to investigate the prognostic implications of ventricular volume on early thin-slice brain computed tomography (CT) after cardiac arrest. We measured the gray-to-white matter ratio (GWR) and the characteristics and volumes of the lateral, third, and fourth ventricles. The primary outcome was a poor 6-month neurological outcome. Of the 166 patients, 115 had a poor outcome. The fourth ventricle was significantly smaller in the poor outcome group (0.58 cm3 [95% CI, 0.43-0.80]) than in the good outcome group (0.74 cm3 [95% CI, 0.68-0.99], p < 0.001). Ventricular characteristics and other ventricular volumes did not differ between outcome groups. The area under the curve for the fourth ventricular volume was 0.68, comparable to 0.69 for GWR. Lower GWR (<1.09) and lower fourth ventricular volume (<0.41 cm3) predicted poor outcomes with 100% specificity and sensitivities of 8.7% (95% CI, 4.2-15.4) and 20.9% (95% CI, 13.9-29.4), respectively. Combining these measures improved the sensitivity to 25.2% (95% CI, 17.6-34.2). After adjusting for covariates, the fourth ventricular volume was independently associated with neurologic outcome. A marked decrease in fourth ventricular volume, with concomitant hypoattenuation on CT scans, more accurately predicted outcomes.

An experimental test of endfire synthetic aperture sonar for sediment characterisation

AbstractThe validation of seafloor scattering models used for seabed characterisation requires quantifying the contributions from the sediment interface and volume to the total acoustic returns. At low‐frequencies, direct measurements of sediment volume scattering have rarely been made, due to the bias in interface roughness scattering caused by large beamwidths of low‐frequency sonars. Endfire Synthetic Aperture Sonar (EF‐SAS) can achieve narrower beamwidths by forming a vertically oriented synthetic array as a transmitter and/or receiver and moving it through the water column. The narrower beamwidths achieved by EF‐SAS allow for more accurate measurements of volume scattering by reducing interface scattering bias in acoustic returns. The application of EF‐SAS for sediment characterisation is explored for the first time. The authors demonstrate that EF‐SAS can be used to construct the angular response curve for both interface and volume scattering as well as to estimate the attenuation and reflection coefficients, which can be inverted for grain size.

Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer.

Colorectal cancer (CRC) is a prevalent cancer type in clinical settings; its early signs can be difficult to detect, which often results in late-stage diagnoses in many patients. The early detection and diagnosis of CRC are crucial for improving treatment success and patient survival rates. Recently, imaging techniques have been hypothesized to be essential in managing CRC, with magnetic resonance imaging (MRI) and spiral computed tomography (SCT) playing a significant role in enhancing diagnostic and treatment approaches. To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic treatment. Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with CRC. The precision of MRI and SCT for the presurgical classification of CRC was assessed, and pathological staging was used as a reference. Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume, blood flow, time to peak, permeability surface, blood reflux constant, volume transfer constant, and extracellular extravascular space volume fraction on the prognosis of patients with CRC. Pathological biopsies confirmed the following CRC stages: 23, 23, 32, and 17 at T1, T2, T3, and T4, respectively. There were 39 cases at the N0 stage, 22 at N1, 34 at N2, 44 at M0 stage, and 51 at M1. Using pathological findings as the benchmark, the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity, specificity, and accuracy compared with either modality alone, with a statistically significant difference in accuracy (P < 0.05). Receiver operating characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis, as indicated by the areas under the curve for blood volume, blood flow, time to peak, and permeability surface, blood reflux constant, volume transfer constant, and extracellular extravascular space volume fraction were 0.750, 0.683, 0.772, 0.761, 0.709, 0.719, and 0.910, respectively. The corresponding sensitivity and specificity values were also obtained (P < 0.05). MRI with SCT is effective in the clinical diagnosis of patients with CRC and is worthy of clinical promotion.

A DFT study to explore structural, elastic, mechanical, phonon, electronic and optical properties of halide perovskites AgXF3(X=Be,Ca)$$ {\mathrm{AgXF}}_3\left(\mathrm{X}=\mathrm{Be},\mathrm{Ca}\right) $$ with PBEsol, TB‐mBJ and SCAN functionals

AbstractFirst principles calculations have been performed using full potential linearized augmented plane wave, FP‐LAPW, within Wien2k to elucidate structural, elastic, mechanical, phonon, electronic and optical properties of lead free halide perovskites . The energy volume curve fitting is used to examine structural stability. For structural optimization and mechanical properties, we employed Perdew–Burke–Ernzerhof generalized gradient approximation and PBEsol, revised for solids, exchange and correlation functional. The optimized lattice constant of and is 3.631 and 4.349Å. The elastic constant , and are computed to extract different mechanical parameters like Poisson's ratio, Pugh's ratio, bulk modulus, shear modulus, Young's modulus, anisotropic ratio, Cauchy pressure and shear constant. The mechanical parameters exhibit greater structural, mechanical and dynamical stability of than . The electronic and optical properties are calculated by using TB‐mBJ and SCAN potentials in addition to PBEsol. The electronic band gap of and is 4.71 and 6.01 eV with TB‐mBJ and both perovskites are indirect band gap materials. The optical response of these perovskites against wide range of incident electromagnetic radiation is assessed by calculating absorption, reflection, optical conductivity, dielectric constant, energy loss function and refraction. Strong absorption, high optical conductivity and low reflectivity indicates that and are promising materials for photovoltaic applications.

The Ecosystem as Super-Organ/ism, Revisited: Scaling Hydraulics to Forests under Climate Change.

Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO2) uptake and water vapor loss, important for predicting and managing the future of Earth's ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.e., representing the ecosystem as an aggregate of its individuals or as a metaphorical or literal super-organ or organism. We review recent approaches to scaling-up plant water relations (hydraulics) concepts developed for organs and organisms to enable and interpret measurements at ecosystem-level. We focus on three community-scale versions of water relations traits that have potential to provide mechanistic insight into climate change responses of forest CO2 and H2O gas exchange and productivity: leaf water potential (Ψcanopy), pressure volume curves (eco-PV), and hydraulic conductance (Keco). These analyses can reveal additional ecosystem-scale parameters analogous to those typically quantified for leaves or plants (e.g., wilting point and hydraulic vulnerability) that may act as thresholds in forest responses to drought, including growth cessation, mortality, and flammability. We unite these concepts in a novel framework to predict Ψcanopy and its approaching of critical thresholds during drought, using measurements of Keco and eco-PV curves. We thus delineate how the extension of water relations concepts from organ- and organism-scales can reveal the hydraulic constraints on the interaction of vegetation and climate and provide new mechanistic understanding and prediction of forest water use and productivity.

Liriodenine and Its Probable Role as an Osmolyte during Water Stress in Annona lutescens (Annonaceae)

In tropical deciduous forests (TDFs), plants have developed various strategies to tolerate desiccation during the dry season. One strategy is osmotic adjustment, which includes the accumulation of secondary metabolites. Annona lutescens, a species that inhabits TDFs, increases and accumulates liriodenine alkaloid in its roots during the dry season. In this study, we evaluate the possible role of this molecule as an osmolyte and in pH homeostasis. We performed growth analyses and determined liriodenine concentrations during water stress in Annona lutescens seedlings grown under controlled temperature, water, and light conditions. We also calculated their osmotic adjustment based on pressure–volume curves and performed solubility tests along a pH gradient. Osmotic adjustment was compared between control plants (irrigated) and plants subjected to 15, 25, and 35 days of water stress. Osmotic adjustment was dramatically higher in plants subjected to 35 days of water stress compared to the control. The solubility of liriodenine was 54% at pH 4.5, and when liriodenine was in contact with malic acid solutions, the pH increased slightly. The highest concentration of liriodenine was in the roots, with a significant increase from 540.855 μg g−1 after 15 days of water stress to 1239.897 μg g−1 after 35 days. Our results suggest that liriodenine plays an important role in the response to water stress as an osmolyte and in pH homeostasis.

Multi-objective optimization of membrane cavity curve of diaphragm compressor and its verification

According to the trend of compressor upgrades in hydrogen refueling stations, this article optimizes the single exponential curve of membrane chamber volume and diaphragm stress that performs poorly. First, set the optimization goals as the membrane cavity volume and the arc length of the curve, use the MOPSO algorithm to optimize the curve, and fit the optimization results to obtain a new curve mathematical model. Then, select three curves for comparison. Theoretical calculations and finite element simulations were performed on the membrane cavity volume and diaphragm stress, and the theoretical calculation methods and results were verified with the help of existing experiments. Finally, it was found that the new curve can increase the membrane cavity volume and reduce the diaphragm stress requirement by changing its own parameters, and the new curve has a small amount of cavity volume near the transition point, which has little impact on the membrane cavity volume. Under the same maximum radial stress, the membrane cavity volume of the new curve can be increased by 5.56% compared to the single exponential curve, while under the same membrane cavity volume, the new curve can reduce the maximum stress on the gas side by 8.9% compared with the single exponential curve, and the maximum stress on the oil sides is reduced by 9.8%.

ARIMA-based Freight Forecasting and Network Optimization in E-commerce Logistics

Considering the proliferation of e-commerce platforms exemplified by Taobao and JD, the paradigm of online shopping has evolved into an integral facet of contemporary societal existence. To enhance network transport performance, it is essential to predict freight volume, assess existing capacity, and establish new sites to alleviate network pressure. This study focuses on a logistics transportation network, utilizing daily freight turnover data from January 1, 2021, to December 31, 2022. The ARIMA time series method is employed to forecast freight volumes at different sites within the e-commerce logistics network. Taking three logistics site route combinations, namely DC14→DC10, DC20→DC35, and DC25→DC62, as examples, two differencing operations are applied to meet the stationarity requirement of the ARIMA model. Autocorrelation and partial autocorrelation coefficients are used for preliminary model order determination. By minimizing the Akaike Information Criterion (AIC) value, an ARIMA (5) model is established. Single and multiple-step predictions are conducted, resulting in forecast curves for future freight volumes. Subsequently, an evaluation of the transportation network is performed, considering the importance of nodes and routes. The entropy weight method is applied to determine the weights of evaluation indicators. Importance indices for nodes and routes are calculated, leading to a ranking. For the assessment and selection of new site capabilities, Fisher's discriminant function is employed to classify different sites. The valuation level for site selection is determined, providing a scientific basis for the systematic choice of new sites.

Preliminary study on the mechanical behavior of clay in one-dimensional compression with DEM simulations

The mechanical behavior and physical properties of clay are closely associated with its microstructure. Current research on the macroscopic mechanics and physical properties of clay is comprehensive and systematic. However, the microstructural variations underlying these characteristics have been predominantly examined under mercury intrusion porosimetry and scanning electron microscopy, while quantitative and systematic studies are notably limited. This research employs the discrete element method (DEM) simulation to investigate the microscopic responses of clay, simulating one-dimensional compression tests on two clay types: card-house and book-house structures. The analysis of pore size and morphology was conducted using virtual mercury intrusion porosimetry and the pore segmentation method. The clay microstructure was quantitatively characterized by parameters such as pore aspect ratio, orientation distribution, and cumulative pore volume curve. The findings demonstrate that DEM effectively replicates the fundamental mechanical behavior of clay, revealing and explaining the evolution pattern of clay pore structure during one-dimensional compression in terms of platelet alignment adjustment. This macroscopic compression is characterized by variations in pore size distribution, orientation, and aspect ratio.

Evaluation and clinical significance of contrast-enhanced ultrasound on changes in liver blood flow perfusion after TIPS surgery.

To investigate the clinical value of contrast-enhanced ultrasound in the prediction of hepatic encephalopathy (HE) in patients with hepatitis B cirrhosis after intrahepatic portal-systemic shunt via jugular vein. In this retrospective study, we collected data from 75 patients with hepatitis B, cirrhosis, and portal hypertension who underwent jugular intrahepatic portosystemic shunt from February 2019 to February 2022. The diagnostic instrument used was the TOSHIBA Aplio500 color Doppler ultrasound with contrast-enhanced ultrasound capabilities. The trial group comprised 20 patients with HE within 3 months postsurgery, while the control group (CG) included 55 patients without HE within the same postoperative period. All patients underwent various examinations before and within 48 hours after surgery, including observation of liver and spleen size and stent position, as well as assessment of blood flow direction in portal and hepatic veins. Subsequently, contrast-enhanced ultrasound was employed to examine and observe perfusion changes of contrast agents in hepatic veins, hepatic arteries, and portal veins (PV). Changes in PV pressure gradient, intrahepatic, and stent blood flow perfusion (BFP) were explored in both postoperative trials and CGs. The trial group exhibited higher BFP volume, PV pressure gradient difference, and percentage decrease compared to the CG. A weak positive correlation was observed between blood flow within the liver stent and PV pressure gradient difference, as well as the percentage decrease in PV pressure gradient. The correlation coefficient between blood flowing perfusion volume within the stent and the difference in PV pressure gradient was R = 0.415 (P = .000). The correlating coefficient between BFP amount within the stent and the percentage decrease in PV pressure gradient was R = 0.261 (P = .027). The area under the receiver operating characteristic curve for stent perfusion volume, difference in PV pressure gradient, and percentage decrease in PV pressure gradient was 0.691, 0.759, and 0.742, respectively. An increase in PV pressure gradient accelerates blood flow within the stent, predisposing to HE. Changes in hepatic BFP following transjugular intrahepatic portosystemic shunt can effectively predict the occurrence of HE, demonstrating significant clinical relevance.

AI-enabled left atrial volumetry in coronary artery calcium scans (AI-CACTM) predicts atrial fibrillation as early as one year, improves CHARGE-AF, and outperforms NT-proBNP: The multi-ethnic study of atherosclerosis

BackgroundCoronary artery calcium (CAC) scans contain actionable information beyond CAC scores that is not currently reported. MethodsWe have applied artificial intelligence-enabled automated cardiac chambers volumetry to CAC scans (AI-CACTM) to 5535 asymptomatic individuals (52.2% women, ages 45–84) that were previously obtained for CAC scoring in the baseline examination (2000–2002) of the Multi-Ethnic Study of Atherosclerosis (MESA). AI-CAC took on average 21 ​s per CAC scan. We used the 5-year outcomes data for incident atrial fibrillation (AF) and assessed discrimination using the time-dependent area under the curve (AUC) of AI-CAC LA volume with known predictors of AF, the CHARGE-AF Risk Score and NT-proBNP. The mean follow-up time to an AF event was 2.9 ​± ​1.4 years. ResultsAt 1,2,3,4, and 5 years follow-up 36, 77, 123, 182, and 236 cases of AF were identified, respectively. The AUC for AI-CAC LA volume was significantly higher than CHARGE-AF for Years 1, 2, and 3 (0.83 vs. 0.74, 0.84 vs. 0.80, and 0.81 vs. 0.78, respectively, all p ​< ​0.05), but similar for Years 4 and 5, and significantly higher than NT-proBNP at Years 1–5 (all p ​< ​0.01), but not for combined CHARGE-AF and NT-proBNP at any year. AI-CAC LA significantly improved the continuous Net Reclassification Index for prediction of AF over years 1–5 when added to CHARGE-AF Risk Score (0.60, 0.28, 0.32, 0.19, 0.24), and NT-proBNP (0.68, 0.44, 0.42, 0.30, 0.37) (all p ​< ​0.01). ConclusionAI-CAC LA volume enabled prediction of AF as early as one year and significantly improved on risk classification of CHARGE-AF Risk Score and NT-proBNP.