Rate Of Volume Change Research Articles

Acceleration of Brain Atrophy and Progression From Normal Cognition to Mild Cognitive Impairment

It remains unclear which risk factors accelerate brain atrophy along with a progression from normal cognition to mild cognitive impairment (MCI). To examine risk factors associated with the acceleration of brain atrophy and progression from normal cognition to MCI based on long-term longitudinal data for middle-aged and older adults. Data for this cohort study were extracted from the Biomarkers for Older Controls at Risk for Dementia (BIOCARD) cohort, initiated at the National Institutes of Health from January 1, 1995, to December 31, 2005, and continued at Johns Hopkins University from January 1, 2015, to October 31, 2023. All participants were cognitively normal at baseline. The participants whose structural magnetic brain imaging (MRI) of the brain and cerebrospinal fluid (CSF) measures were available for over 10 years were included. Longitudinal structural MRI of the brain and measurement of CSF biomarkers for Alzheimer disease pathology (ratio of amyloid β peptide 42 [Aβ42] to Aβ40, tau phosphorylated at threonine 181, and total tau). Annual change rates of segmental brain volumes, Kaplan-Meier survival curves plotting time to event for progression to MCI symptom onset, and hazard ratios (HRs) determined by Cox proportional hazards regression models. A total of 185 participants (mean [SD] age, 55.4 [8.4] years; 116 women [63%]) were included and followed up for a maximum of 27 years (median, 20 [IQR, 18-22] years). The groups with high levels of atrophy in the white matter and enlargement in the ventricles had an earlier progression from normal cognition to MCI symptom onset (HR for white matter, 1.86 [95% CI, 1.24-2.49]; P = .001; HR for ventricles, 1.71 [95% CI, 1.19-2.24]; P = .009). Diabetes was associated with progression to MCI (HR, 1.41 [95% CI, 1.06-1.76]; P = .04), as was a low CSF Aβ42:Aβ40 ratio (HR, 1.48 [95% CI, 1.09-1.88]; P = .04), and their combination had a higher HR of 1.55 (95% CI, 1.13-1.98]; P = .03), indicating a synergic association of diabetes and amyloid pathology with MCI progression. In this cohort study of middle-aged and older adults, higher rates of volume change in the white matter and ventricles, along with the presence of diabetes and a low CSF Aβ42:Aβ40 ratio, were identified as important risk factors for the progression to MCI. These results support the importance of identifying individuals who have accelerated brain atrophy to optimize preventive strategies for progression to MCI.

Predictive Modelling and Functional Group of Clay Soil Treated with Steel Slag and Calcium Carbide Residue

Swell-shrink subgrade soils like clay are rich in sulphate and exhibit a high rate of volume change by swelling and shrinking during wet and dry cycles, respectively, leading to heaves, cracks, and differential settlement of pavement layers. The aim of this study was to establish predictive simulation models and functional group of clay soil treated with steel slag and calcium carbide residue. Physical and geotechnical tests (such as California bearing ratio (CBR), compaction characteristics, and consistency parameters) were carried out on the unstabilised and stabilised clay soil. Using SPSS statistical software (version 23), multiple linear regression analysis was applied to the experimental data that relate CBR to compaction parameters and additive contents (steel slag and calcium carbide residues). The generated models gave a reliable coefficient of determination, R2 , of 0.990, and 0.998, which can be used to successfully predict both unsoaked and soaked CBR of the stabilised clay soil, respectively. Fourier transform infrared spectroscopy (FTIR) analysis was examined on the clay soil, the additives, and the stabilised clay soils. The FTIR analysis showed weak peaks at 1115 and 1103 cm-1 for all the stabilised clay soils, and this revealed that both additives drastically reduced the sulphate content in the clay soil, which consequently reduced the expansion, cracking, and disintegration rates. As a result, the clay soil's chemical bonding was enhanced through physico- chemical mechanisms.

Evaluation of water supply function in the Economic Belt of the Northern Slope of the Tianshan Mountains based on the InVEST model

The Economic Belt of the Northern Slope of the Tianshan Mountains (EBNSTM) is a composite ecosystem with mountains, oases, and desert areas; it also serves as an active area for anthropogenic activities. Frequent changes in soil and water resources have significant impacts on regional ecosystems. However, research on the ecosystem water yield function of EBNSTM is relatively limited; additionally, the spatiotemporal variations in the water supply function based on land use changes have not been sufficiently elucidated. This study aimed to explore the land use changes and the spatial variability of water supply service functions in the region at the macro level and uses the land transfer matrix as an important tool to study the changes in land use in the different years of 2000, 2005, 2010, 2015, and 2020. Using the InVEST model, we conducted a quantitative assessment and comprehensive study on the water supply function of EBNSTM across the aforementioned years. Additionally, the study delved into the structure of ecosystem service functions, alongside investigating the spatial and temporal variability of ecosystem services under the multi-scale units of administrative divisions, ecological zones, and land classes. We found that during the 20-year period, the area of construction land of EBNSTM increased by 1089 km2, with the highest dynamic change rate of 4.09 %; 2015–2020 period was the most drastic period of change for each land use type. The average multi-year depth of water production was 87.49 mm, totaling 71.59 × 108 m3. The spatial distribution pattern of the water supply function in the study area during the last 20 years consistently exhibited a distinct pattern: mountainous areas displayed the highest water supply capacity, followed by oases, and deserts ranked the lowest. Further, the water supply service function within the study area is currently experiencing a modest rate of increase. The rate of change in water supply depth was 2.76 mm/a, while the rate of change in water supply volume was 0.47 × 108 m3/a. Areas with enhanced water supply capacity are mostly distributed in the southeast of EBNSTM, whereas the northwest, encompassing the mountainous areas, exhibited a declined water supply capacity. Between 2000 and 2020, the water supply capacity in the study area was ranked as follows: woodland > grassland > unutilized land > cultivated land > urban construction land, with woodland displaying the strongest water supply capacity. When woodlands, grasslands, and croplands were converted to other land use types, their water supply functions generally decreased, and vice versa. Our findings provide a scientific basis for the sustainable management of water and soil resources in EBNSTM.

Lung function decline in people with serious mental illness: A call to action

This prospective observational study aimed to evaluate the rate of change in forced expiratory volume in the first second (FEV1) and to explore the factors associated with changes in FEV1 in people with serious mental illness (SMI). Sixty subjects diagnosed with schizophrenia or bipolar disorder who were smokers and without history of respiratory illness agreed to participate. The mean (range) follow-up period was 3.54 (3.00–4.98) years. The mean (standard deviation) annual rate of change in FEV1 decreased by 39.1 (105.2) mL/year. Thirty-one (51.7 %) patients experienced a decrease in the FEV1 ≥40 mL/year (i.e. a rapid decline). The factors associated with the absolute change in FEV1 were the baseline International Physical Activity Questionnaire activity score in metabolic equivalents of tasks (β 0.145, 95 % confidence interval [CI] 0.043 to 0.246; p = 0.005), baseline FEV1 (β -0.025, 95 % CI -0.076 to 0.027; p = 0.352), and the interaction term of both variables (β -3.172e-05, 95 % CI -6.025e-05 to -0.319e-05; p = 0.029). The factors associated with rapid FEV1 decline were income (odds ratio [OR] 0.999, 95 % CI 0.995 to 1.003; p = 0.572), the rate of change in abdominal circumference (OR 0.000, 95 % CI 0.000 to 0.890; p = 0.081), and the interaction term of both variables (OR 1.038, 95 % CI 1.010 to 1.082; p = 0.026). In conclusion, a substantial proportion of people with SMI experienced a rapid decrease in FEV1. If our results are confirmed in larger samples, the routine evaluation of lung function in people with SMI would be an opportunity to identify individuals at greater risk of morbidity and mortality.

Cementation characteristics and hydration mechanism of magnesium slag-phosphogypsum composite cementitious materials

The selection and mixing proportion of cementitious materials in cemented backfills are of great engineering importance to ensure the quality of the backfill. Therefore, based on the mixing proportion test of magnesium slag-phosphogypsum composite cementitious materials, the strength change characteristics and volume change rate of the cemented backfill under different cementitious material proportions were investigated. Combined with indoor tests such as hydration heat test, X-ray diffraction, thermogravimetric-differential thermogravimetric, scanning electron microscopy, and mercury intrusion porosimetry, the hydration mechanism of the cemented backfill under different cementitious material proportions was investigated. The results showed that the highest strength of the cemented backfill was observed with only magnesium slag as the activator. The strength of magnesium slag-phosphogypsum and magnesium slag-desulfurized gypsum cemented backfill was greater than that of cement cemented backfill, yet lower than that of magnesium slag alone cemented backfill. The shrinkage trend and magnitude of magnesium slag alone excites blast furnace slag cemented backfill and cement cemented backfill were similar. With the increasing content of phosphogypsum and desulfurized gypsum, the shrinkage of the backfill tended to increase, especially when the content was 18%. The gel-like products of backfill with magnesium slag-based cementitious materials increased rapidly at 7 days, which strongly bonded the aggregates and filled the backfill pores, resulting in high backfill strength. Although the porosity of backfill with magnesium slag-based cementitious material showed an increasing trend with the increase of age, its most available pore size decreased and harmful pores became less. The results can provide a reference for the application of magnesium slag-phosphogypsum composite cementitious materials.

Computer Modelling Study of Volume Kinetics in Intraocular Segments Following Airbag Impact Using Finite Element Analysis.

We have previously studied the physiological and mechanical responses of the eye to blunt trauma in various situations using finite element analysis (FEA). In this study, we evaluated the volume kinetics of an airbag impact on the eye using FEA to sequentially determine the volume change rates of intraocular segments at various airbag deployment velocities. The human eye model we created was used in simulations with the FEA program PAM-GENERISTM (Nihon ESI, Tokyo, Japan). Different airbag deployment velocities, 30, 40, 50, 60 and 70 m/s, were applied in the forward direction. The volume of the deformed eye impacted by the airbag was calculated as the integrated value of all meshes in each segment, and the decrease rate was calculated as the ratio of the decreased volume of each segment at particular timepoints to the value before the airbag impact. The minimum volume of the anterior chamber was 63%, 69% and 50% at 50, 60 and 70 m/s airbag impact velocity, respectively, showing a curve with a sharp decline followed by gradual recovery. In contrast to the anterior chamber, the volume of the lens recovered promptly, reaching 80-90% at the end of observation, except for the case of 60 m/s. Following the decrease, the volume increased to more than that of baseline at 60 m/s. The rate of volume change of the vitreous was distributed in a narrow range, 99.2-100.4%. In this study, we found a large, prolonged decrease of volume in the anterior chamber, a similar large decrease followed by prompt recovery of volume in the lens, and a time-lag in the volume decrease between these tissues. These novel findings may provide an important insight into the pathophysiological mechanism of airbag ocular injuries through this further evaluation, employing a refined FEA model representing cuboidal deformation, to develop a more safe airbag system.

Experimental study on the effect of hydrothermal activation on the physicochemical properties and mineralization efficiency of fly ash-supercritical CO2

To address the challenge of low mineralization efficiency of fly ash-supercritical carbon dioxide (CO2), a hydrothermal activation method was proposed to enhance fly ash-supercritical CO2 mineralization. The study systematically investigated the mechanism through which hydrothermal activation parameters influenced the efficiency of fly ash-supercritical CO2 mineralization through a series of experimental reactions. The effects of hydrothermal activation temperature and time on mineralization efficiency were investigated macroscopically. The results indicated that the mineralization efficiency increased by 202.93 % when hydrothermally activated at 220 °C for 30 min. Furthermore, when the activation time was ≤10 min, 220 °C exhibited a significant effect on the mineralization efficiency. For activation time ≥20 min, mineralization efficiency exhibited high stability with increasing temperature. Subsequently, under 220 °C conditions, mineralization efficiency reached 18.79 % for 5 min and 21.69 % for 30 min, representing only a 15.43 % increase despite a six-fold increase in time. Microscopic analysis of the pore structure of hydrothermally activated fly ash indicated that pore parameters (volume, specific surface area, and volume change rate) exceeded those of original fly ash for pore diameters ≥9 nm, and the opposite was observed for pore diameters <9 nm. Additionally, compared with the pristine fly ash, the pore size and volume fraction of the mineralized fly ash macropores increased, while mesopores decreased, and small pores exhibited a slight decrease in volume fraction and size. This indicated that pores ≥9 nm were primarily affected by hydration expansion, while pores <9 nm were primarily affected by mineralization precipitation. The hydrothermal activation mineralization reaction predominantly affected medium and large pores ≥9 nm, exhibiting less effect on smaller pores.

Power prediction of oscillating water column power generation device based on physical information embedded neural network

Due to its simplicity and high reliability, Oscillating Water Column (OWC) wave energy conversion devices hold great promise for practical applications. The optimization of OWC parameters is currently a hot research topic. In this study, we address the challenges of rapid response prediction and parameter optimization for OWC systems by developing a physics-informed neural networks (PINN) model. The influence of different physical constraints on the performance of the PINN model is investigated. Our research demonstrates that incorporating the key parameter of wave elevation in the intermediate layer enhances the interpretability, prediction accuracy, and scalability of the model but may affect its convergence. By including the prior physical knowledge of the correlation between water volume change rate and power generation efficiency into the loss function, the convergence of the neural network model can be improved, albeit with minimal impact on prediction accuracy and scalability. Additionally, introducing the critical laws discovered in subsequent analyses regarding the relationship between wave elevation distribution and power generation efficiency into the loss function enhances the convergence of the PINN model while significantly improving its scalability. In summary, by integrating various physical constraints, including key parameters, prior knowledge, and critical laws, into the neural network model, significant improvements can be achieved in the interpretability, accuracy, convergence, and scalability of the model. The findings of this study highlight the avenues through which neural network model performance can be improved from these three perspectives, aiming to provide guidance for related modeling endeavors.

Effect of Complex Well Conditions on the Swelling and Tribological Properties of High-Acrylonitrile Stator Rubber in Screw Pumps.

The effects of complex well conditions in shale oil wells on the swelling and tribological properties of high-acrylonitrile stator rubber used in screw pumps were investigated in this study. Tests were conducted considering the combined effects of immersion medium, temperature, and duration. The key parameters measured included mass change rate, volume change rate, hardness, elongation at break, tensile strength, surface micro-morphology of the rubber after thermal expansion and swelling, friction coefficient, and wear quantity. The results indicated that in the actual well fluids, the mass change rate of high-acrylonitrile rubber ranged from -1.08% to 1.29%, with a maximum volume change rate of 2.78%. In diesel oil, the greatest mass change rate of the rubber was 4.68%, and the volume change rate did not exceed ±1%, indicating superior swelling resistance. In both actual well fluids and diesel oil, the maximum decreases in hardness were 8.7% and 9.5%, respectively. Tensile strength and elongation at break decreased with increasing immersion temperature, with elongation at break in 80 °C diesel oil decreasing by over 50%, indicating a significant decline in the tensile properties of the rubber. The average friction coefficient of rubber specimens immersed in actual well fluids at three temperatures, as well as in diesel oil at 25 and 50 °C, decreased compared with the high-acrylonitrile rubber without thermal expansion and swelling. However, the average friction coefficient of rubber specimens immersed in diesel oil at 80 °C increased. The wear quantity of the rubber increased following immersion in both media. Additionally, the friction coefficient and wear quantity of the rubber increased with increasing immersion temperatures. The results of the study can offer valuable insights into assessing the durability of properties in high-acrylonitrile stator rubber under complex well conditions.

Experimental investigation on thermal performance of phase change materials–metal foam composites in ocean thermal engine

Because battery-powered underwater vehicles have limited long-term mission capacity, the development of ocean thermal engines that can harvest ocean thermal energy (OTE) is a potential solution to this “energy limitation” issue. Ocean thermal engines using solid-liquid phase change materials (PCM) for thermal–mechanical energy conversion. This study examined the effects of combining PCMs with metal foams (MF) on OTE harvesting. Two phase change materials and three MFs were considered. Experiments were conducted to measure the temperature change inside the PCM, phase change duration, and volume change to evaluate the thermal and energy-harvesting performances under different temperature and pressure conditions. Results show that(1) Mixed PCM composed of 95 % n-hexadecane and 5 % n-octane melting point decreased by 0.9–1.6 °C and volume change rate reduced by 16–40 % compared to pure n-hexadecane. (2) The mixed PCM has by 14–18 % higher output power than pure n-hexadecane. (3) Within the test range, to maximize the power density, the optimal porosity of copper foam and back pressure during melting were 94 % and 20 MPa, respectively. This study provides useful insights into the design and optimization of ocean thermal engines.

Longitudinal changes in the volume of residual lung lobes after lobectomy for lung cancer: a retrospective cohort study.

It is unclear how the residual lobe volume changes over time after lobectomy. This study aims to clarify the temporal patterns of volume changes in each remaining lung lobe post-lobectomy. A retrospective review was conducted on patients who underwent lobectomy for lung cancer at Yueyang Central Hospital from January to December 2021. Lung CT images were reconstructed in three dimensions to calculate the volumes of each lung lobe preoperatively and at 1, 6, and 12months postoperatively. A total of 182 patients were included. Postoperatively, the median total lung volume change rates relative to preoperative values were -20.1%, -9.3%, and -5.9% at 1, 6, and 12months, respectively. Except for the right middle lobe in patients who underwent right upper lobectomy, the volumes of individual lung lobes exceeded preoperative values. The volume growth of the lung on the side of the resection was significantly more than that of the lung on the opposite side. For left lobectomy patients, the right lower lobe's volume change rate exceeded that of the right upper and middle lobes. Among right lobectomy patients, the left lower lobe and the relatively inferior lobe of right lung had higher volume change rates than the superior one. Right middle lobe change rate was more in patients with right lower lobectomy than right upper lobectomy. Six months postoperatively, FEV1% and right middle lobectomy were positively correlated with the overall volume change rate. One year postoperatively, only age was negatively correlated with the overall volume change rate. 75 patients had pulmonary function tests. Postoperative FEV1 change linearly correlated with 1-year lung volume change rate, but not with theoretical total lung volume change rate or segmental method calculated FEV1 change. Time-dependent compensatory volume changes occur in remaining lung lobe post-lobectomy, with stronger compensation observed in the relatively inferior lobe compared to the superior one(s). Preoperative lung function and age may affect compensation level.

A simple method of shape transformation using the modified Gray–Scott model

In this paper, based on the original Gray–Scott model, we propose a modified Gray–Scott model by introducing a target term into the reaction–diffusion equations. We apply this modified model in the context of shape transformation problems. To expedite the process from the source shape to the target shape, we utilize the explicit Euler method to solve our proposed modified Gray–Scott model, making our approach simpler and more efficient. To validate the feasibility of our method, we conduct simulation experiments in both two-dimensional (2D) and three-dimensional (3D) spaces. By progressing through experiments of increasing complexity, we demonstrate the natural effectiveness of our simulation method as a viable approach for shape transformation. To demonstrate the efficiency of the method, we provide the runtime consumed by the simulated shape transformation experiment. Additionally, to assess the correspondence between the ground truth values of the target shape and the simulated results, we calculate the corresponding area change rate and volume change rate in 2D and 3D spaces to prove that our proposed method can effectively transform into the target shape.

Molecular dynamics study of confined liquid film viscosity in Constant-Pressure and Constant-Distance systems

Viscosity changes in confined liquids have been explored using experimental techniques including surface force apparatus (SFA) and fiber wobbling method (FWM), revealing different magnitudes of viscosity increment as the gap between confining solid surfaces decreases. To address this disparity, we performed molecular dynamics simulations to gain insights into the mechanisms of viscosity changes in confined liquid UV-curable resin films used in nanoimprint lithography. Solid surfaces were fixed to maintain a constant pressure or distance, resembling SFA and FWM, respectively. Consistent with experimental results, our simulations confirmed that the viscosity increases with decreasing solid–solid gaps, notably, more pronounced in the constant-distance system than in the constant-pressure one. However, the two systems exhibited no distinct difference in the liquid molecular distribution. By introducing a new concept of free volume change rate, we conducted an in-depth analysis of liquid molecular motion, revealing more active motion in the constant-pressure system, particularly in the central region between the solid surfaces. This motion correlated positively with atomic vibrations of the confining surfaces. Our findings emphasize that different confinement conditions (constant pressure or constant distance) distinctly alter the liquid molecular motion and thus the magnitude of viscosity, underscoring the necessity for precise characterization of the rheological properties of confined UV-curable resins.

Increases in regional brain volume across two native South American male populations

Industrialized environments, despite benefits such as higher levels of formal education and lower rates of infections, can also have pernicious impacts upon brain atrophy. Partly for this reason, comparing age-related brain volume trajectories between industrialized and non-industrialized populations can help to suggest lifestyle correlates of brain health. The Tsimane, indigenous to the Bolivian Amazon, derive their subsistence from foraging and horticulture and are physically active. The Moseten, a mixed-ethnicity farming population, are physically active but less than the Tsimane. Within both populations (N = 1024; age range = 46–83), we calculated regional brain volumes from computed tomography and compared their cross-sectional trends with age to those of UK Biobank (UKBB) participants (N = 19,973; same age range). Surprisingly among Tsimane and Moseten (T/M) males, some parietal and occipital structures mediating visuospatial abilities exhibit small but significant increases in regional volume with age. UKBB males exhibit a steeper negative trend of regional volume with age in frontal and temporal structures compared to T/M males. However, T/M females exhibit significantly steeper rates of brain volume decrease with age compared to UKBB females, particularly for some cerebro-cortical structures (e.g., left subparietal cortex). Across the three populations, observed trends exhibit no interhemispheric asymmetry. In conclusion, the age-related rate of regional brain volume change may differ by lifestyle and sex. The lack of brain volume reduction with age is not known to exist in other human population, highlighting the putative role of lifestyle in constraining regional brain atrophy and promoting elements of non-industrialized lifestyle like higher physical activity.

Inducing Na+ Site Rearrangement Through a Cosubstitution Strategy for Rapid Na Diffusion Kinetics of P2-Type Layered Metal Oxides.

The P2-layered metal oxide cathode materials are crucial for constructing high-rate sodium-ion batteries (SIBs); however, its practical application is hindered by the high Na+ diffusion barrier resulting from Na+/vacancy ordering. Herein, a Li/Zn cosubstitution P2-Na0.67Ni0.33Mn0.67O2 (NLNZM) cathode was synthesized via a sol-gel method assisted with citric acid, which can induce the rearrangement of Na+ sites to disrupt ordered structures. The XRD Rietveld refinement confirms a higher occupancy of Na+ at Nae sites with low diffusion barriers through the Li/Zn cosubstitution. In addition, the highly reversible phase evolution of the NLNZM is confirmed through in situ XRD results, thereby ensuring the stability of the structure with low volume change rate (0.78%). Furthermore, Li and Zn can reduce the surface energy and increase the interlayered distance to achieve rapid interfacial kinetics. As a result, the NLNZM has exhibited a high reversible capacity of 152.8 mAh g-1 and an outstanding rate performance of 103.4 mAh g-1 at 5C. After 200 cycles at 5C, the capacity retention rate is 81.1%. This work proposes a cosubstitution strategy to induce Na+/vacancy disorder for achieving rapid Na+ migration as a cathode material for SIBs.

Development and Validation of Deep Learning-Based Automated Detection of Cervical Lymphadenopathy in Patients with Lymphoma for Treatment Response Assessment: A Bi-institutional Feasibility Study.

The purpose is to train and evaluate a deep learning (DL) model for the accurate detection and segmentation of abnormal cervical lymph nodes (LN) on head and neck contrast-enhanced CT scans in patients diagnosed with lymphoma and evaluate the clinical utility of the DL model in response assessment. This retrospective study included patients who underwent CT for abnormal cervical LN and lymphoma assessment between January 2021 and July 2022. Patients were grouped into the development (n = 76), internal test 1 (n = 27), internal test 2 (n = 87), and external test (n = 26) cohorts. A 3D SegResNet model was used to train the CT images. The volume change rates of cervical LN across longitudinal CT scans were compared among patients with different treatment outcomes (stable, response, and progression). Dice similarity coefficient (DSC) and the Bland-Altman plot were used to assess the model's segmentation performance and reliability, respectively. No significant differences in baseline clinical characteristics were found across cohorts (age, P = 0.55; sex, P = 0.13; diagnoses, P = 0.06). The mean DSC was 0.39 ± 0.2 with a precision and recall of 60.9% and 57.0%, respectively. Most LN volumes were within the limits of agreement on the Bland-Altman plot. The volume change rates among the three groups differed significantly (progression (n = 74), 342.2%; response (n = 8), - 79.2%; stable (n = 5), - 8.1%; all P < 0.01). Our proposed DL segmentation model showed modest performance in quantifying the cervical LN burden on CT in patients with lymphoma. Longitudinal changes in cervical LN volume, as predicted by the DL model, were useful for treatment response assessment.

Study on unconfined compressive strength and deformation characteristics of chlorine saline soil

The distribution of saline soil is wide and the area is large in China. The saline soil in different regions shows their own characteristics. The saline soil of single salt is configured by adding different contents of NaCl to the loess in Xi'an. The effects of chlorine content and water content on soil strength and volume change in a large water content range was studied, and the change mechanism was analyzed by scanning electron microscopy. The results show that the strength of chloride saline soil increases with the decrease of water content. The moisture content of 12% is the critical point of strength change of chloride saline soil. When the moisture content is greater than 12%, the strength of soil decreases with the increase of salt content. When the water content is less than 12%, the strength of saline soil is 3% NaCl content > 1% NaCl content > 5% NaCl content > 0% NaCl content. The volume change of the sample consists of three parts: elastic deformation during sample pressing, volume shrinkage during water loss and salt expansion. In the absence of NaCl and 1% NaCl content, the sample was in the state of shrinkage during the loading process, in which with the decrease of moisture content shrinkage rate slowed down. The volume change rate of 3% and 5% NaCl showed an inflection point from negative to positive when the water content was 15%. When the water content is less than 12%, the saline soil with 3% NaCl content has the characteristics of high strength and unobvious salt expansion. The method of adding 3% NaCl to loess in Xi 'an area can be used to simulate the cement between soil particles, which provides a reference for artificially preparing structural soil. According to the microstructure analysis, the higher the salt content of saline soil, the smaller the soil pores, and the contact form of soil particles gradually develops from the point contact between soil particles to the salt-wrapped structure.

Enhancing Exchange-Traded Fund Price Predictions: Insights from Information-Theoretic Networks and Node Embeddings.

This study presents a novel approach to predicting price fluctuations for U.S. sector index ETFs. By leveraging information-theoretic measures like mutual information and transfer entropy, we constructed threshold networks highlighting nonlinear dependencies between log returns and trading volume rate changes. We derived centrality measures and node embeddings from these networks, offering unique insights into the ETFs' dynamics. By integrating these features into gradient-boosting algorithm-based models, we significantly enhanced the predictive accuracy. Our approach offers improved forecast performance for U.S. sector index futures and adds a layer of explainability to the existing literature.

Different inflammatory signatures based on CSF biomarkers relate to preserved or diminished brain structure and cognition

Neuroinflammation is a hallmark of Alzheimer’s disease (AD) and both positive and negative associations of individual inflammation-related markers with brain structure and cognitive function have been described. We aimed to identify inflammatory signatures of CSF immune-related markers that relate to changes of brain structure and cognition across the clinical spectrum ranging from normal aging to AD. A panel of 16 inflammatory markers, Aβ42/40 and p-tau181 were measured in CSF at baseline in the DZNE DELCODE cohort (n = 295); a longitudinal observational study focusing on at-risk stages of AD. Volumetric maps of gray and white matter (GM/WM; n = 261) and white matter hyperintensities (WMHs, n = 249) were derived from baseline MRIs. Cognitive decline (n = 204) and the rate of change in GM volume was measured in subjects with at least 3 visits (n = 175). A principal component analysis on the CSF markers revealed four inflammatory components (PCs). Of these, the first component PC1 (highly loading on sTyro3, sAXL, sTREM2, YKL-40, and C1q) was associated with older age and higher p-tau levels, but with less pathological Aβ when controlling for p-tau. PC2 (highly loading on CRP, IL-18, complement factor F/H and C4) was related to male gender, higher body mass index and greater vascular risk. PC1 levels, adjusted for AD markers, were related to higher GM and WM volumes, less WMHs, better baseline memory, and to slower atrophy rates in AD-related areas and less cognitive decline. In contrast, PC2 related to less GM and WM volumes and worse memory at baseline. Similar inflammatory signatures and associations were identified in the independent F.ACE cohort. Our data suggest that there are beneficial and detrimental signatures of inflammatory CSF biomarkers. While higher levels of TAM receptors (sTyro/sAXL) or sTREM2 might reflect a protective glia response to degeneration related to phagocytic clearance, other markers might rather reflect proinflammatory states that have detrimental impact on brain integrity.

Non-isochoric stable granular models taking into account fluidisation by pore gas pressure

In this paper, we study non-isochoric models for mixtures of solid particles, at high volume concentration, and a gas. One of the motivations for this work concerns geophysics and more particularly the pyroclastic density currents, whose dense basal parts are precisely mixtures of pyroclasts and lithic fragments and air. They are extremely destructive phenomena, capable of devastating urbanised areas, and are known to propagate over long distances, even over almost flat topography. Fluidisation of these dense granular flows by pore gas pressure is one response that could explain this behaviour and must therefore be taken into account in the models. Starting from a solid–gas mixing model and invoking the compressibility of the gas through a law of state, we rewrite the conservation of mass equation of the gas phase into an equation of the pore gas pressure whose net effect is to reduce the friction between the particles. The momentum equation of the solid phase is completed by generic constitutive laws, specified as in Schaeffer et al. (J. Fluid Mech., vol. 874, 2019, pp. 926–951) by a yield function and a dilatancy function. Therefore, the divergence of the velocity field, which reflects the ability of the granular flow to expand or compress, depends on the volume fraction, pressure, strain rate and inertial number. In addition, we require the dilatancy function to describe the rate of volume change of the granular material near an isochoric equilibrium state, i.e. at constant volume. This property ensures that the volume fraction, which is the solution to the conservation of mass equation, is positive and finite at all times. We also require that the non-isochoric fluidised model be linearly stable and dissipate energy (over time). In this theoretical framework, we derive the dilatancy models corresponding to classical rheologies such as Drucker–Prager and $\mu (I)$ (with or without expansion effects). The main result of this work is to show that it is possible to obtain non-isochoric and fluidised granular models satisfying all the properties necessary to correctly account for the physics of granular flows and which are well posed, at least linearly stable.