Length Density Research Articles

Application of Hybrid External Skeletal Fixation with Bone Tissue Engineering Techniques for Comminuted Fracture of the Proximal Radius in a Dog

A seven-month-old male Pomeranian presented with left forelimb lameness after a fall. Radiographic assessment confirmed proximal radial head and ulnar comminuted fracture. The initial surgical intervention involved the use of hybrid external skeletal fixation (ESF) to stabilize the radial head, concomitant with the application of a composite of bone morphogenetic protein type 2 (BMP-2)-loaded hydroxyapatite and gelatin microparticles at the fracture site. Although successful radial head healing was achieved, the ESF pinholes caused a defect in the proximal ulnar diaphysis. Subsequently, the ESF was removed, and a locking plate was applied in conjunction with the BMP-2-loaded collagen membrane to correct the radius defect. Clinical follow-up at 4.8 years postoperatively revealed a mildly decreased range of motion of the affected elbow joint, but no clinical symptoms such as lameness. Radiography revealed minimal degenerative changes and a radioulnar synostosis. Computed tomography revealed differences in the leg length and bone density. Gait analysis revealed that the left forelimb had a significant improvement in weight-bearing capacity based on weight distribution–peak vertical force metrics, compared with the right forelimb. Based on clinical outcomes, the combined application of hybrid ESF and bone tissue engineering techniques can be considered a feasible alternative treatment for radial head fractures.

Structure, microstructure, and ESR properties of concentration-dependent Zn1-xMnxO nanoparticles

In this study, the estimated stress, strain, and crystallite sizes of different Mn-doped ZnO nanoparticles were calculated using the Williamson-Hall method and compared with the values obtained from the Debye-Scherrer formula. Moreover, defects, and magnetic properties of Mn-doped ZnO nanoparticles at different concentrations were investigated. The sol-gel method was used to synthesize nanoparticles. The X-ray diffraction and Rietveld analysis results confirm that the desired structure is formed and that no secondary phase is present up to an Mn concentration of x=0.2. In and out of plane lattice parameters, cell volumes, bond length, atomic locality, and dislocation density (δ) were clarified. The grain size of the concentration-dependent samples was provided by scanning electron microscope. Photoluminescence (PL) spectra exhibited ultraviolet emission along with a broad band encompassing violet, blue, and red regions, attributed to defect-related and excitonic emissions. These emissions were notably influenced by synthesis conditions and doping elements and ratios. Electron spin resonance properties of the concentration-dependent samples were analyzed to figure out the g-factor through line widths of pike-to-pike (ΔHPP) of ESR spectra. Mn-doped ZnO nanoparticles exhibited ferromagnetism at room temperature.

Reactive retinal vasodilation may mask capillary loss in eyes without diabetic retinopathy and isolated neurodegeneration

Reactive retinal vasodilation occurs in healthy individuals when the demand for oxygen surpasses the supply that the vascular bed can provide. This phenomenon may also occur in individuals with diabetes who do not have diabetic retinopathy, potentially masking circulation deficiencies caused by early capillary closure. As a result, eyes with reactive retinal vasodilation may show a seemingly normal circulation area, while also displaying other diabetes-related changes such as neurodegeneration. Our hypothesis suggests that in eyes without overt ischemia, which is one of the phenotypes of diabetic retinal disease, neurodegeneration could be the result of undetected ischemia in the presence of reactive retinal vasodilation. We propose methodologies to investigate this hypothesis, including the assessment of retinal capillaries using optical coherence tomography angiography, as well as the measurement of neurodegeneration markers such as retinal sensitivity, electroretinogram amplitude reductions, and retinal layer thinning. Additionally, we outline an approach for estimating the contribution of large retinal vessels to the percentage of circulation within a measured retinal area, using variables such as vessel length density and vessel area density. If our hypothesis is confirmed, it could lead to the early identification of ischemia before the onset of diabetic retinopathy and offer an opportunity to assess interventions when endothelial and neural damage can still be mitigated.

Learning continuous scattering length density profiles from neutron reflectivitiesusing convolutional neural networks

Abstract Interpreting neutron reflectivity (NR) data using ad hoc multi-layer models and
physics-based models provides information about spatially resolved neutron scattering
length density (NSLD) profiles. Recent improvements in data acquisition systems
have allowed acquiring thousands of NR curves in a couple of hours, which has led to
a need for automated data analysis tools to interpret NR measurements in real-time.
Here, we present a machine learning analysis workflow that uses a series of models,
based on a Convolutional Neural Network (CNN), to learn the relation between the
NSLDs and the NRs, and subsequently produce continuous NSLD profiles directly
from NRs. The usefulness of our CNN-based models is demonstrated by constructing
NSLDs from NRs of several films containing homopolymer polyzwitterions (PZs) and
diblock copolymers mixed with different types of salts. Comparisons of the NSLDs
with those constructed using ad hoc multi-layer models reveal a very good agreement,
suggesting the potential of CNN-based models for real-time automated data analysis
of NRs.

Genetic variations in morphology, chromosome number, and physiology of backcross progeny of the triploid hybrid clone ‘Beilinxiongzhu 1#’

BackgroundAneuploidy in plants commonly presents as large variations in morphology, physiology, biochemistry, and genetic effects owing to its karyotypic imbalance.ResultsIn this study, the trait variations of 393 offspring obtained by pollinating Populus alla × Populus glandulosa ‘YXY 7’ (2n = 2x = 38) with Populus ‘Beilinxiongzhu 1#’ (2n = 3x = 57) were explored. The results showed several morphological variations in the cotyledons, including two (69.68%), three (24.07%), and four cotyledons (6.25%). Additionally, the progeny exhibited extensive segregation of ploidy levels, ranging from 38 to 74. Furthermore, seedlings with different chromosome numbers varied in growth traits and physiological activities during growth and development. The backcross progeny with 51–60 chromosomes had a significantly larger basal diameter and seedling height than those with other chromosome numbers. The phenotypic correlations between the traits indicated that the dose effect of the chromosomes significantly affected the basal diameter, petiole length, and leaf length, particularly with stomatal length and stomatal density. Weak and negative estimated correlations were observed between the physiological traits associated with photosynthesis and most of the studied traits.ConclusionsThis study provides new genetic material with different chromosome compositions, which will contribute to analyzing chromosomal function and integrate the variations in chromosomal dosage into Populus breeding programs.

Choriocapillaris flow deficit is associated with disease duration in type 2 diabetic patients without retinopathy: a cross-sectional study

BackgroundDiabetes mellitus (DM) causes microvascular damage due to long-term hyperglycemia, even before the onset of retinal changes. We aimed to investigate the association between optical coherence tomography angiography (OCTA) metrics and disease duration in type 2 diabetic patients without retinopathy.MethodsEighty-two eyes of 82 type 2 diabetic patients without diabetic retinopathy (DR) were included. Choriocapillaris flow deficit (CC FD%), vessel density (VD), vessel length density (VLD) in the superficial (SVP) and deep vascular plexus (DVP) were calculated and compared between different sectors of the macula. Foveal avascular zone circularity (FAZc) was also calculated. Linear regression was used to study the association of each vascular parameter with disease duration both in a univariate and multivariate design adjusting for age, sex, Hb1Ac and arterial hypertension.ResultsCC FD% increased by 3.7, 2.3, 3.8 and 4.6% in the nasal, superior, temporal and inferior sectors per decade of disease duration, after adjusting for confounders. Mean values of VD and VLD in the SVP and DVP, as well as FAZc decreased with increased duration of DM, but the association was weaker. Only the VD in the superior and temporal sectors of the SVP were significant in the multivariate analysis (ß=-0.12 (95% CI -0.24 to -0.01) and − 0.13 (95%CI -0.25 to -0.002), respectively).ConclusionCC FD% is independently associated with disease duration in type 2 diabetes independent of the presence of clinical retinopathy. Further longitudinal studies are needed to investigate the role of choroidal changes in predicting DR onset in order to individualize screening protocols.

Vascular Characteristics of Treatment-resistant and -responsive Actinic Keratosis Identified with Dynamic Optical Coherence Tomography.

Treatment-resistant actinic keratosis (AK) is of concern in clinical practice, often requiring retreatment. Microvascular assessments might help differentiate treatment-resistant from treatment-responsive AKs, enabling targeted treatment. Using dynamic optical coherence tomography, AK vascularization was investigated following daylight photodynamic therapy, comparing treatment-resistant with cleared AKs. AKs on face/scalp were graded according to the Olsen Classification Scheme and scanned with dynamic optical coherence tomography pre-treatment, and 3- and 12-months post-treatment. Employing dynamic optical coherence tomography, total vessel length, mean vessel length, mean vessel diameter, vessel area density, and branchpoint density were quantified. Thirty-eight patients with 62 AKs were enrolled, including 37 AK I, 18 AK II, and 7 AK III. Treatment-resistant AKs displayed a trend toward intensified vascularization compared with cleared AK at baseline (AKs I, II), suggested by higher total vessel length (median 144.0, IQR 104.3-186.6) and vessel area density (median 27.7, IQR 18.4-34.2) than in cleared AK (median 120.9, IQR 86.9-143.0 and median 22.9, IQR 17.3-26.8). Additionally, vascularization in treatment-resistant AK I-II appeared disorganized, with trends toward shorter mean vessel length (median 151.0, IQR 138.5-167.5) and increased branchpoint density (median 3.2, IQR 2.3-3.8) compared with cleared AK (median 160.0, IQR 152.0-169.3 and median 2.6, IQR 2.2-3.0). These findings suggest that dynamic optical coherence tomography holds potential to identify treatment-resistant AKs.

Surface Depth Analysis of Chemical Changes in Random Copolymer Thin Films Composed of Hydrophilic and Hydrophobic Silicon-Based Monomers Induced by Plasma Treatment as Studied by Hard X-ray Photoelectron Spectroscopy and Neutron Reflectivity Measurements.

In this study, a silicon-based copolymer, poly(tris(trimethylsiloxy)-3-methacryloxypropylsilane)-co-poly(N,N-dimethyl acrylamide), thin film was subjected to plasma surface treatment to make its surface hydrophilic (biocompatible). Neutron reflectivity (NR) measurement of the plasma-treated thin film showed a decrease in the film thickness (etching width: ∼20 nm) and an increase in the scattering length density (SLD) near the surface (∼15 nm). The region with a considerably high SLD adsorbed water (D2O) from its saturated vapor, indicating its superior surface hydrophilicity. Nevertheless of the hydrophilicity, the swelling of the thin film was suppressed. Hard X-ray photoelectron spectroscopy (HAXPES) performed at various takeoff angles revealed that the thin-film surface (∼20 nm depth) underwent extensive oxidation. NR and HAXPES analysis quantitatively yielded the depth profiling of elemental compositions in a few tens of nm scale. Si oxidation and hydrogen elimination (probably CH3 groups) in the vicinity of the surface region increased the SLD and decreased the hydrophobicity. A combination of Soft X-ray photoelectron spectroscopy and NR measurements revealed the surface chemical composition and mass density. It was considered that the surface near the film was chemically composed close to SiO2, forming a gel-like (three-dimensional network) structure that is hydrophilic and suppresses swelling due to moisture, indicating it can be expected to maintain stable hydrophilicity on the film surface.

Phosphazene Tripeptide Conjugates: Design, Synthesis, In Vitro Cytotoxicity and Genotoxicity, Molecular Interactions in Binding Pockets on Human Breast and Colon Cancer Cell Lines.

The biological activity of both cyclophosphazenes and peptides makes these compounds important for new studies in medicinal chemistry. For this purpose, five different phosphazene-peptide conjugates synthesized from dichlorocyclotriphosphazene and tyrosine-containing tripeptides. The synthesized compounds were evaluated for their in vitro cytotoxic activities against human breast (MCF-7) and colon (Caco-2) cancer cell lines using MTT assay. The derivatives induced cell death through DNA damage, with notable effects in Caco-2 cell lines. Specifically, DTVV, DTVG, and DTVA were cytotoxic at 50 and 100 μM, while DTVP and DTVM were effective at 25, 50, and 100 μM. DTVM outperformed Tamoxifen at 50 μM in the MCF-7 cell line. DNA damage studies of the compounds were performed using the comet assay method, evaluating tail length, tail density, olive tail moment, head length, and head density parameters. The findings indicated that cell death occurred via a DNA damage mechanism. The molecular intricacies of DTVA, DTVG, DTVM, DTVP and DTVV within the VEGFR2 kinase domain (3VHE) and Cyclophilin_CeCYP16-Like Domain (2HQ6) binding pockets and various interactions, docking scores and potential activities of these derivatives were investigated. The differences in docking scores and interaction profiles highlight the potential efficacy and specificity of these compounds in targeting breast and colon cancer cells. These findings highlight the potential of phosphazene-peptide derivatives as therapeutic agents in cancer treatment.

Effect of Flax By-Products on the Mechanical and Cracking Behaviors of Expansive Soil.

Expansive soils, prone to significant volume changes with moisture fluctuations, challenge engineering infrastructure due to their swelling and shrinking. Traditional stabilization methods, including mechanical and chemical treatments, often have high material and environmental costs. This study explores fibrous by-products of flax processing, a sustainable alternative, for reinforcing expansive clay soil. Derived from the Linum usitatissimum plant, flax fibers offer favorable mechanical properties and environmental benefits. The research evaluates the impact of flax tow (FT) reinforcement on enhancing soil strength and reducing cracking. The results reveal that incorporating up to 0.6% randomly distributed FTs, consisting of technical flax fibers and shives, significantly improves soil properties. The unconfined compressive strength (UCS) increased by 29%, with 0.6% FT content, reaching 525 kPa, compared to unreinforced soil and further flax tow additions, which led to a decrease in UCS. This reduction is attributed to diminished soil-fiber interactions and increased fiber clustering. Additionally, flax tows effectively reduce soil cracking. The crack length density (CLD) decreased by 6% with 0.4% FTs, and higher concentrations led to increased cracking. The crack index factor (CIF) decreased by 71% with 0.4% flax tows but increased with higher FT concentrations. Flax tows enhance soil strength and reduce cracking while maintaining economic and environmental efficiency, offering a viable solution for stabilizing expansive clays in geotechnical applications.

The SGLT2 inhibitor empagliflozin exerts neuroprotective effect against hydrogen peroxide-induced toxicity on primary neurons.

Oxidative stress has been implicated in several chronic pathological conditions, leading to cell death and injury. Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) have several overlapping mechanisms as they are both characterized by increased oxidative stress, inflammation, insulin resistance, and autophagy dysfunction. The objective of this study was to elucidate the possible neuroprotective effect of empagliflozin, a sodium-glucose co-transporter 2 inhibitor (SGLT2i), against hydrogen peroxide-induced neurotoxicity in primary hippocampal neurons derived from wild-type (WT) and transgenic AD rats (TgF344-AD). An in vitro oxidative stress model was established using hydrogen peroxide to induce damage to neurons. Empagliflozin pretreatment was tested on this model initially through a cell viability assay. Flow cytometry and cell sorting were employed to discriminate the apoptotic and necrotic neuronal cell populations. Finally, the morphological and morphometric features of the neurons, including dendritic length and spine density, were evaluated using the SNT ImageJ plug-in following immunostaining with GFP. Sholl analysis was used to evaluate the impact of empagliflozin and hydrogen peroxide on dendritic arborization. Empagliflozin tended to ameliorate hydrogen peroxide-induced toxicity in primary neurons derived from WT rats and led to the preservation of dendritic spine density in both WT and TgF344-AD neurons (one-way ANOVA, p < 0.05). A modest improvement in dendrites' length was also observed. Empagliflozin pretreatment can partially mitigate dendritic and spine alterations induced by hydrogen peroxide in primary neurons. These results underscore the impact of empagliflozin on neuronal morphology and highlight its potential as a candidate for the treatment and/or prevention of AD.

Structure and dynamics of the active site of hen egg-white lysozyme from atomic resolution neutron crystallography.

Hen egg-white lysozyme (HEWL) is a widely used model protein in crystallographic studies and its enzymatic mechanism has been extensively investigated for decades. Despite this, the interaction between the reaction intermediate and the catalytic Asp52, as well as the orientation of Asn44 and Asn46 side chains, remain ambiguous. Here, we report the crystal structures of perdeuterated HEWL and D2O buffer-exchanged HEWL from 0.91 and 1.1Å resolution neutron diffraction data, respectively. These structures were obtained at room temperature and acidic pH, representing the active state of the enzyme. The unambiguous assignment of hydrogen positions based on the neutron scattering length density maps elucidates the roles of Asn44, Asn46, Asn59, and nearby water molecules in the stabilization of Asp52. Additionally, the identification of hydrogen positions reveals unique details of lysozyme's folding, hydrogen (H)/deuterium (D)exchange, and side chain disorder.

Variations of soil infiltration in response to vegetation restoration and its influencing factors on the Loess Plateau

Soil infiltration is essential in the hydrological cycle, fulfilling plant water requirements, particularly in semi-arid regions such as the Loess Plateau. However, comprehensive characterization of soil infiltration responses to different vegetation restoration types remains unclear. Therefore, this study aims to examine the effects of revegetation on soil infiltration by conducting field experiments with nine representative plant species across five vegetation restoration types. Specifically, we focused on how revegetation affects soil and root properties to determine key factors impacting soil infiltration. The results showed that artificial forestland and natural grassland exhibited the most substantial effects on soil properties. Natural grassland exhibited the highest soil aggregate stability and organic matter content. Root length density and root surface area increased after vegetation restoration, most notably in artificial forestland. Root characteristics were positively correlated with aggregate stability, soil organic matter, and porosity. An increase in root surface area significantly enhanced the steady infiltration rate and saturated hydraulic conductivity (P < 0.01). Except for economic forestland, all types of vegetation restoration improved soil infiltration properties, especially notable in Artemisia sacrorum and Platycladus orientalis. The soil infiltration properties in forestland surpassed those in natural grassland, artificial grassland, and shrubland. Random Forest Regression (RFR) suggested that soil particle size, porosity, and aggerate stability were key predictors of soil infiltration properties. Partial least squares structural equation modeling (PLS-SEM) indicated that soil infiltration rates were altered by root-mediated changes in soil porosity. Additionally, soil organic matter exerts an indirect positive effect on infiltration rates by influencing soil aggregate stability. These findings are crucial for evaluating hydrological processes and devising more effective ecological restoration and soil and water conservation strategies in the Loess Plateau.

Comparative study between swept-source and spectral-domain OCTA for imaging of choroidal neovascularization in age-related macular degeneration.

To compare the differences of choroidal neovascularization (CNV) measurements between swept-source and spectral-domain optical coherence tomography angiography (SS-OCTA and SD-OCTA) in neovascular age-related macular degeneration (nAMD) and the imaging reliability of the two devices. Prospective comparative study. SS-OCTA and SD-OCTA were used to scan the same eye with the modes of 3×3 and 6×6 mm2 centered on the neovascularization. Only qualified images were chosen and the border of CNV was manually delineated by two graders independently. The area of CNV (ACNV), vascular perfusion density (PD), and vessel length density (VLD) within the delineation were calculated using Image J. The differences of CNV measurements between the two OCTA devices were compared using Bland-Altman analysis. The agreement between the two graders on the measurements of each device was compared using the intraclass correlation coefficient (ICC). A total of 18 patients (22 eyes) with nAMD were included. The measurements of ACNV, PD, and VLD were 7.247±4.586 and 4.901±3.741 mm2, 43.202±9.636 and 34.904±10.489, 6.339±1.228 and 5.908±1.741 mm-1 for SS-OCTA and SD-OCTA, respectively. The differences between the two devices were 2.346±3.030 mm2 (Z=-3.782, P<0.0001), 8.298±14.160 (Z=-2.419, P=0.016), and 0.431±2.114 mm-1 (Z=-0.828, P=0.408) for ACNV, PD and VLD, respectively. The ICC between two graders were 0.893 (P<0.001), 0.902 (P<0.001), 0.885 (P<0.001) for ACNV, PD, VLD in SS-OCTA, and 0.971 (P<0.001), 0.976 (P<0.001), 0.973 (P<0.001) in SD-OCTA, respectively. Both OCTA devices have high imaging reliability. Compared with SD-OCTA, SS-OCTA has a larger ACNV measurements, but doesn't show better resolution of internal vessels of CNV and well signal strength.

Molecular dynamics study of the microstamping of TiAl6V4 alloy.

Microstamping has been shown to enhance the surface strength of alloy materials by improving interatomic density. This paper delves into the damage mechanism of TiAl6V4(TC4), which has been processed using high-speed stamping with varying overlap ratios at the atomic level. Additionally, the general trend of stress variation between loading and unloading is discussed. The mechanical properties of the substrate and the changes in microstructure resulting from varying overlap rates in microstamping were investigated. The impact of different machining overlap ratios on the depth of the damaged layer, the number of dislocation density lines, and the density of the matrix is also explored. The results indicate that the dislocation density remains relatively unchanged due to material hardening, while the overlap ratio increases continuously. Based on this analysis, a more optimal microstamping overlay ratio parameter is proposed to effectively enhance the surface strength of the substrate and reduce processing time. First, an alloy model with titanium, aluminum, and vanadium was created in ATOMSK and LAMMPS software. The model was divided into three layers: fixed, constant temperature, and Newton. To ensure the accuracy of the simulation, the system was annealed in order to minimize energy and replicate real-world conditions. Zhou's EAM alloy potential was employed to represent the interaction between the alloy atoms, while the Tersoff potential was used to represent the interatomic interaction of the diamond indenter. Additionally, the LJ potential function was selected to depict the interaction between the metal atom and the diamond indenter. The construct surface mesh method in OVITO software was then utilized to construct a surface mesh and analyze the impact of different machining overlap rates on surface topography. The common neighborhood analysis (CNA) module in OVITO was used to calculate the number of defective atoms and the depth of the damaged layer. Finally, the DXA (dislocation extraction analysis) module in OVITO was used to calculate the dislocation density length and dislocation density.

X-ray Reflectivity Probing the Structural Evolution of Sunflower Proteins Adsorbed at the Air-Water Interface.

The study delves into the adsorption of sunflower proteins at the air/water interface using specular X-ray reflection. The research involved fitting models of the protein films to the reflectivity data, resulting in detailed images of the X-ray scattering length density profiles perpendicular to the air/water interface. The sunflower protein isolate that is examined consists of multiple components, and the study proposes a transition from a 1-slab model to a 4-slab model to represent the changing layer structure over time. This transition is significant as it reflects the increasing complexity of the protein film as more proteins adsorb at the interface. Initially, sunflower proteins form a monolayer at the air/water boundary, consisting of a protein-rich, hydrophobic portion closest to the interface and a more diffuse, hydrophilic portion extending into the bulk aqueous phase. The structural changes at the interface over time depend on the bulk protein concentration in the solution. For solutions at relatively low concentrations (C ≤ 0.5 g/L), a lower amount of adsorption results in a larger, more extensive interface area for each species and a thinner protein adsorption layer. The overall thickness of a saturated monolayer is approximately 100 Å, which is close to the maximum dimension of sunflower globulins, with the thickness of the corresponding hydrophobic portion being about 20 Å. For solutions at relatively high concentrations (C ≥ 1.0 g/L), even after forming a saturated monolayer, structural evolution continues within the experimental time frame, occurring on both hydrophilic and hydrophobic sides. Additional proteins from the bulk diffuse toward the interface, forming an extra layer in the water phase and causing an increase in the overall thickness. Furthermore, a distinct sublayer develops next to the air phase, indicating a further structuration of the hydrophobic portion.

Effects of different land-use types on soil detachment capacity in loess areas

Against the background of similar geomorphological characteristics and environmental temperatures, land-use types alter the soil detachment capacity (Dc) by changing soil properties and root traits. However, there is a lack of in-depth discussion regarding the response of Dc to land-use types in loess areas. The purpose of this study was to quantify the influences of different land-use types in loess areas on Dc, soil erodibility (kr), and critical shear stress (τc) and explore the key factors affecting Dc under runoff erosion based on the links between root traits and soil properties, and combined with PLS-SEM algorithm, a meta-model of Dc influence mechanism was established. Two hundred and seventy undisturbed soil samples were collected from six different land-use types and scoured under nine specific combinations of flow rate and slope (flow rate: 0.167–0.5 L s−1, slope: 10.5–20.8 %). The results showed that with the change in land-use type, Dc changed considerably. The average Dc of the shrubland was only 1/22 of that of the cropland. The change trend of kr was consistent with that of Dc, while the change trend of τc had no obvious regularity. The relationships between the root density parameters and Dc were simulated using the exponential function and Hill curve, respectively, and the predictive effect of the Hill curve was better than that of the exponential function. Compared with the other comprehensive hydraulic parameters, shear stress (τ) was Dc’s most effective predictive factor. Correlation and path analyses revealed that soil organic matter (SOM) and root length density (RLD) were the best indicators of Dc. Furthermore, a dimensionless Dc prediction model suitable for different land-use types was established based on τ, SOM, and RLD, and the model exhibited a high accuracy (R2 = 0.955, NSE = 0.911).

Comparison of trial lens-fitting and software-fitting in orthokeratology for myopia control in children with high corneal eccentric value

PurposeTo compare the safety and efficacy of the trial lens-fitting and software-fitting in orthokeratology for myopia control in children with high corneal eccentric value. MethodsMyopic children with high corneal eccentric value (≥0.65) receiving treatment for orthokeratology from July 2020 to January 2022 were included in this retrospective study. Only the right eyes were included. The participants were allocated into two groups: the trial lens-fitting group (n = 41) and the software-fitting group (n = 48). The uncorrected visual acuity (UCVA), corneal topography, and ocular health (Efron grading scales) were recorded at baseline, one week, two weeks, one, three, six, and 12 months afterthe initiation of lens wear. The axial length and endothelial cell density were assessed at baseline and after 12 months of lens wear. ResultsThe success rate of the first fit in the software-fitting group and trial lens-fitting group reached 98 % and 95 %, respectively. The difference in UCVA and corneal staining were statistically insignificant between the two groups during all visits. The software-fitting group exhibited a smaller treatment zone size (radius 1.69 ± 0.21 mm vs 1.81 ± 0.16 mm, p = 0.004; area 9.13 ± 2.15 mm2 vs 10.36 ± 1.82 mm2, p = 0.005) and less decentration (0.58 ± 0.31 mm vs 0.74 ± 0.39 mm, p = 0.036) compared with the trial lens-fitting group. There were no significant differences in axial elongation (0.15 ± 0.12 mm vs. 0.17 ± 0.14 mm, p = 0.534) or changes in endothelial cell density (−36.63 ± 99.37/mm2 vs − 13.71 ± 87.72/mm2, p = 0.256) between the software-fitting group and the trial lens-fitting group at one-year follow-up visit. ConclusionBoth fitting methods were effective and safe. However, the software-fitting method resulted in a smaller treatment zone size and less decentration.

COD and CSD based model for in-plane stiffness of symmetric laminates with cracks in plies and local delaminations: Analysis of crack face sliding

In-plane thermo-elastic constants of symmetric damaged laminates containing transverse cracks in plies and local delaminations starting from crack tip are predicted using a crack opening (COD) and crack sliding displacement (CSD) based approach. An exact elastic analysis shows that the displacement gap on the delamination crack surfaces does not enter the stiffness expressions explicitly. The delamination affects the stiffness via larger COD and CSD of the intralaminar crack. This means that the same expressions for cracked laminates with and without delaminations can be used but with different expressions for COD and CSD. Finite element method is used to analyze the CSD dependence on delamination length and crack density. The obtained approximative expressions for CSD are in a good agreement with FEM. It is shown that in cases when it depends on CSD only, the predicted shear modulus of laminates is in an excellent agreement with direct FEM calculations. The used homogenization over couples of off-axis plies (monoclinic materials) in CSD expressions for balanced laminates is validated.

Artificial humic acid promotes carbon sequestration in rice-soil system

Artificial humic acid (AHA) is a new exogenous organic material with enormous carbon sequestration potential. However, the effects and mechanisms of applying AHA under different irrigation regimes on carbon sequestration in rice-soil systems still need to be clarified. This study applied carbon isotope labeling technology to analyze the photosynthetic carbon sequestration capacity, the carbon transport capacity of the root, and greenhouse gas emission flux in the rice-soil system under different irrigation regimes and AHA application conditions. The results showed that as the amount of AHA applied increased, the leaf area and chlorophyll concentration gradually increased, the Rubisco activity first increased and then decreased under two irrigation regimes. In alternate wetting and drying irrigation with 300 mg kg-1 AHA treatment (DWI3), the photosynthetic carbon fixation ability was the highest, with Pn, Fv/Fm, and qP increasing by 65.35%, 214.85%, and 43.15% compared to alternate wetting and drying irrigation without applying AHA treatment (DWI0), respectively. Meanwhile, during DWI3 treatment, the organic acid concentration in root exudates, root biomass, root length, root surface area, and root length density were also the highest. In summary, among all treatments in this study, the content of 13C in soil under DWI3 treatment was highest, closely related to the strongest photosynthetic carbon fixation and root transport capacity under this treatment, as well as the lower greenhouse gas emission flux. Therefore, it is recommended to apply 300 mg kg-1 AHA with alternate wetting and drying irrigation for carbon sequestration, water conservation, and sustainable agricultural development.