Microstructural Changes Research Articles

Effect of phytic acid on chemical, structural, and mechanical characteristics of nickel–titanium endodontic files

This study investigated phytic acid (IP6) effect on chemical, structural, and mechanical characteristics of nickel–titanium (NiTi) files. The tested files were equally divided into groups according to the immersion protocol: sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), IP6, EDTA followed by NaOCl, and IP6 followed by NaOCl. These groups were then compared in terms of Ni, Ti, and chromium (Cr) ions release from the files. Microstructural changes using field emission scanning electron microscope (Fe-SEM) and energy dispersive X-ray spectroscopy (EDX) and surface roughness were analyzed. The mechanical characterization was conducted using cyclic fatigue resistance test. Fractured segments were scanned under SEM. Statistical analysis was performed using one-way ANOVA, Tukey test, Kruskal–Wallis test and Mann–Whitney U test. Results showed that NaOCl caused significant release of Cr, followed by IP6 and EDTA (P < 0.05). When files were pre-immersed in EDTA, NaOCl tended to induce less release of Ti and Cr. EDX evaluation revealed that the main surface elements were Ni, Ti, carbon, and oxygen. EDTA group contained the highest amount of carbon, while the control group showed the lowest. Surface roughness evaluation revealed no significant differences between groups despite the minor increases after immersion in certain groups. Black areas were observed in the NaOCl group which indicated corrosion. However, the cyclic fatigue test showed no significant differences between the groups.

No significant alteration in white matter microstructure in first-degree relatives of patients with obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is characterized by structural alteration within white matter tissues of cortico-striato-thalamo-cortical, temporal and occipital circuits. However, the presence of microstructural changes in the white matter tracts of unaffected first-degree relatives of patients with OCD as a vulnerability marker remains unclear. Therefore, here, diffusion-tensor magnetic resonance imaging (DTI) data were obtained from 29 first-degree relatives of patients with OCD and 59 healthy controls. We investigated the group differences in FA using whole-brain analysis (DTI analysis). For additional regions of interest (ROI) analysis, we focused on the posterior thalamic radiation and sagittal stratum, shown in recent meta-analysis of patients with OCD. In both whole-brain and ROI analyses, using a strict statistical threshold (family-wise error rate [FWE] corrected p<.05 for whole-brain analyses, and p<.0125 (0.05/4) with Bonferroni correction for ROI analyses), we found no significant group differences in FA. Subtle reductions were observed in the anterior corona radiata, forceps minor, cingulum bundle, and corpus callosum only when a lenient statistical was applied (FWE corrected p<.20). These findings suggest that alterations in the white matter microstructure of first-degree relatives, as potential vulnerability markers for OCD, are likely subtle.

Time-dependent 532 nm laser irradiation for tuning in optical, structural, and surface wettability changes of Te/In2Se3 thin films for optoelectronic applications

Laser irradiation for tuning the optoelectronic parameters of semiconducting thin films is widely applicable and has many benefits. The aim of the study is 532 nm laser irradiation of Te/In2Se3 film at different laser exposure time scales. The bilayer structure and its conversion to a single layer with laser annealing were confirmed from cross-sectional scanning electron microscopy. At the same time, the element's appearance was found in the EDX analysis. FESEM probed the corresponding surface structure change. XRD and Raman's spectroscopy analyzed the increase in crystallinity with laser irradiation by mixing Te into the In2Se3 layer and related microstructural changes. The shift in Raman peak with lasing time signifies the effect of time of exposure. There is a systematic decrement in the transmittance of the films. Also, the absorption edge shift resulted in the decrement in bandgap with laser irradiation. The static refractive index and optical density increased as well. The skin depth was decreased with a minimal change in the optical electronegativity. The nonlinear refractive index increased from 1.638 × 10–9 esu to 1.773 × 10–9 esu by 60 min laser irradiation. Similarly, there was an increment in 3rd-order nonlinear susceptibility from 1.58 × 10–10 esu to 1.73 × 10–10 esu. The surface wettability test confirmed the hydrophilic nature of the samples with decreasing hydrophilicity by laser irradiation. The tuning in different properties of the Te/In2Se3 film by laser irradiation is suitable for various optoelectronic applications.

Preparation and in vitro digestion of algal oil emulsion gel candy with high oxidation stability based on cold‐set gelation method

SummaryAlgal oil emulsion gel candies were prepared by a cold‐set gelation method, and the oxidative stability was analysed. Then, the release of algal oil and the microstructural changes of gel candies were investigated under in vitro simulated digestion conditions. The formula of gel candy was found to be 65% sucrose, 5% algal oil emulsion, 1.8% sodium alginate, 1.2% high methoxy pectin and 2% D‐glucono‐δ‐lactone. Cold‐set gel candies loaded with algal oil emulsion had good oxidative stability. Emulsion gel candies could maintain a relatively intact gel network structure in a gastric fluid environment, in which the DHA release rate was less than 5%, whereas the gel structure was loosened at 30 min of digestion in simulated intestinal fluid and destroyed at 60 min, with a release rate of about 75%. Altogether, these results lay a theoretical foundation for facilitating the development of novel DHA functional foods.

Microstructural evolution and mechanical behaviors of rock salt in energy storage: A molecular dynamics approach

The microstructure of rock salt significantly influences its macroscopic mechanical behaviors and deformation phenomena. Understanding the deformation and failure characteristics of rock salt at multiple scales is crucial for the secure and efficient functioning of energy storage in salt caverns. Although the macroscopic behaviors of rock salt are well understood, the microstructural changes occurring under uniaxial compression have not been thoroughly investigated. This study aims to investigate the evolving laws of rock salt microstructure and mechanical properties during the damage process, thereby providing a fundamental understanding of the underlying mechanism. To achieve this, a series of characterization tests on rock salt were conducted to study its microstructure and defects. Building on this, molecular dynamics simulations were utilized in rock mechanics to elucidate the mechanical behaviors, structural evolutions, and dislocation motions of rock salt during the damage process. The rock salt obtained from Qianjiang, China, is a polycrystalline material with an average subgrain size of 46 nm and an average dislocation density of 4.76 × 10−6 1/Å2. Uniaxial compression of single crystal NaCl exhibits three stages: elastic compression, rapid dislocation multiplication, and forest hardening. Scattered dislocations and isolated dislocation tangles trigger further plastic slippage, leading to decreased strength. Later, the formation of a dislocation cell network hinders further slip and reinforces the strength of rock salt. Plastic deformation is found to be a dominant factor in grain refinement and the formation of polycrystalline structures. Intergranular cracking results from cross-patterned dislocation lines on grain boundaries, which become vulnerable areas of the structure. This study describes the evolutionary process of rock salt microstructures and mechanical properties, identifies the micro-destruction mechanisms during the damage process at the ionic level, and provides insights into the micro-mechanical behavior of rock salt and for the design and stability assessment of underground energy storage facilities.

Effect of recycled fiber modified by CNTs-epoxy resin composite coating on mechanical properties of mortar

In this study, the wastes GFRP was mechanically crushed and recycled GFRP fibers with a uniform aspect ratio were obtained through vibration screening and water separation treatment. In light of the surface-based interfacial defects present in recycled GFRP fibers, an epoxy resin-based nanocomposite coating reinforced with carbon nanotubes (CNTs) was employed for interfacial modification. The chemical properties of the recycled GFRP fibers before and after modification were characterised by XRD, FTIR and DTA. The changes in alkali resistance, mechanical properties and microstructure of the recycled fibers before and after modification were investigated by Alkali resistance test, mechanical testing and Scanning Electron Microscopy (SEM). Results indicated that the improvement of the coating on the fibers mainly included, blocking the erosion of alkali ions on the surface of the fibers and improving the mechanical properties of the fibers, reduced the shrinkage, and water absorption, with the highest compressive and flexural strength of 59.60 MPa and 7.13 MPa, respectively. The surface roughness due to the presence of resin and CNTs prevents easy debonding of fibers from the mortar. This property promotes strong bonding of fibers with the mortar matrix resulting in more effective fiber performance and improved mortar strength while enabling fiber recycling.

Effect of Ceramic Veneering on the Microstructure of Pre-sintered Cobalt-Chromium, Compared to Pre-sintered Zirconia and Conventional Cast Alloys.

Objectives: We aimed to evaluate ceramic-alloy interface and emphasize the alteration of alloy microstructure after ceramic layering. Materials and Methods: Thirty-two discs made from a ceramic-alloy combination of pre-sintered cobalt-chromium (CoCr), cast CoCr, cast nickel-chromium (NiCr), or pre-sintered zirconia were prepared with eight discs in each group. Four specimens were examined as manufactured and four were ceramic-layered. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-Ray diffractometer (XRD), and an atomic force microscope were used for analysis. Non-layered specimens received ceramic fire-heating without adding any ceramic. Alloy microstructure was compared before and after ceramic veneering or heating within the same group. Mean differences in grain size and surface roughness were compared among groups. P<0.05 was considered significant. Results: SEM showed a close bonding interface between alloys and ceramics. EDX demonstrated differences compared to the manufacturer's composition. Ceramic-layering reduced grain size for both milled alloys (P<0.05), whereas grain size increased in cast groups (P=0.011). Heat treatment did the same for the CoCr groups (P=0.013). Ceramic veneering increased the surface roughness of the cast CoCr (Gi) (P=0.029) and NiCr (Wi) (P=0.005) groups, whereas zirconia roughness average (Ra) showed a slight decrease (P=0.282). XRD showed no differences among zirconia, NiCr, and milled CoCr groups before and after veneering. Crystallite size differed between monoclinic and tetragonal phases in zirconia. Conclusion: The study highlights that ceramic-layering induces significant microstructural changes in alloys, enhancing bonding potential and mechanical stability. Pre-sintered materials show a fine homogeneous surface, optimizing ceramic adherence and potentially improving clinical outcomes.

Diffusion tensor metrics, motor and non-motor symptoms in de novo Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic neurons' degeneration of the substantia nigra, presenting with motor and non-motor symptoms. We hypothesized that altered diffusion metrics are associated with clinical symptoms in de novo PD patients. Fractional Anisotropy (FA) and Mean (MD), Axial (AD), and Radial Diffusivity (RD) were assessed in 55 de novo PD patients (58.62 ± 9.85 years, 37 men) and 55 age-matched healthy controls (59.92 ± 11.25 years, 34 men). Diffusion-weighted images and clinical variables were collected from the Parkinson's Progression Markers Initiative study. Tract-based spatial statistics were used to identify white matter (WM) changes, and fiber tracts were localized using the JHU-WM tractography atlas. Motor and non-motor symptoms were evaluated in patients. We observed higher FA values and lower RD values in patients than controls in various fiber tracts (p-TFCE < 0.05). No significant MD or AD difference was observed between groups. Diffusion metrics of several regions significantly correlated with non-motor (state and trait anxiety and daytime sleepiness) and axial motor symptoms in the de novo PD group. No correlations were observed between diffusion metrics and other clinical symptoms evaluated. Our findings suggest microstructural changes in de novo PD fiber tracts; however, limited associations with clinical symptoms reveal the complexity of PD pathology. They may contribute to understanding the neurobiological changes underlying PD and have implications for developing targeted interventions. However, further longitudinal research with larger cohorts and consideration of confounding factors are necessary to elucidate the underlying mechanisms of these diffusion alterations in de novo PD.

Development and Validation of Artificial Intelligence Models for Prognosis Prediction of Juvenile Myoclonic Epilepsy with Clinical and Radiological Features.

Background: Juvenile myoclonic epilepsy (JME) is a common adolescent epilepsy characterized by myoclonic, generalized tonic-clonic, and sometimes absence seizures. Prognosis varies, with many patients experiencing relapse despite pharmacological treatment. Recent advances in imaging and artificial intelligence suggest that combining microstructural brain changes with traditional clinical variables can enhance potential prognostic biomarkers identification. Methods: A retrospective study was conducted on patients with JME at the Severance Hospital, analyzing clinical variables and magnetic resonance imaging (MRI) data. Machine learning models were developed to predict prognosis using clinical and radiological features. Results: The study utilized six machine learning models, with the XGBoost model demonstrating the highest predictive accuracy (AUROC 0.700). Combining clinical and MRI data outperformed models using either type of data alone. The key features identified through a Shapley additive explanation analysis included the volumes of the left cerebellum white matter, right thalamus, and left globus pallidus. Conclusions: This study demonstrated that integrating clinical and radiological data enhances the predictive accuracy of JME prognosis. Combining these neuroanatomical features with clinical variables provided a robust prediction of JME prognosis, highlighting the importance of integrating multimodal data for accurate prognosis.

Investigation of mechanical properties and high temperature wear resistance of CoFeNi1.5VZr0.4Six high entropy alloys optimized by Si alloying

The current work studies the mechanical properties and high-temperature wear resistance of CoFeNi1.5VZr0.4Six high entropy alloys by Si alloying. The Si alloying transforms Ni7Zr2 into a more wear-resistant silicide phase, and the microstructure changes from lamellar eutectic structure to dendritic structure. The high temperature microhardness, compressive strength and fracture toughness of the HEAs increase first and then decrease with the increasing Si content. The Si alloying in HEAs brings about significant improvements in wear resistance at elevated temperature through the combined effects of phase structure modifications and compositional changes in the tribo-layer. The augmented mechanical properties of the worn subsurface layer contribute to improved wear resistance at elevated temperatures.

Differential Tractography: A Biomarker for Neuronal Function in Neurodegenerative Disease.

GM1 gangliosidosis is an ultra-rare inherited neurodegenerative lysosomal storage disorder caused by biallelic mutations in the GLB1 gene. GM1 is uniformly fatal and has no approved therapies, although clinical trials investigating gene therapy as a potential treatment for this condition are underway. Novel outcome measures or biomarkers demonstrating the longitudinal effects of GM1 and potential recovery due to therapeutic intervention are urgently needed to establish efficacy of potential therapeutics. One promising tool is differential tractography, a novel imaging modality utilizing serial diffusion weighted imaging (DWI) to quantify longitudinal changes in white matter microstructure. In this study, we present the novel use of differential tractography in quantifying the progression of GM1 alongside age-matched neurotypical controls. We analyzed 113 DWI scans from 16 GM1 patients and 32 age-matched neurotypical controls to investigate longitudinal changes in white matter pathology. GM1 patients showed white matter degradation evident by both the number and size of fiber tract loss. In contrast, neurotypical controls showed longitudinal white matter improvements as evident by both the number and size of fiber tract growth. We also corroborated these findings by documenting significant correlations between cognitive global impression (CGI) scores of clinical presentations and our differential tractography derived metrics in our GM1 cohort. Specifically, GM1 patients who lost more neuronal fiber tracts also had a worse clinical presentation. This result demonstrates the importance of differential tractography as an important biomarker for disease progression in GM1 patients with potential extension to other neurodegenerative diseases and therapeutic intervention.

Simple construction of efficient graphite supported NiCoCu functional catalysts for methanol oxidation reaction using mechanical milling

A low-energy methodology has been proposed to synthesized Ni-based binary and ternary compounds from M-acetylacetonates (M = Ni, Co and Cu) and mechanical milling (MM) to be used as electrocatalysts for the methanol oxidation reaction in alkaline medium (1 M KOH). The strategies used in this study expand the possibilities of obtaining materials with efficient electrocatalytic activities from noble metal-free catalysts, while reducing the production cost. The prepared electrodes were characterized to evaluate changes in the thermal decomposition, as well as chemical, structural, morphological and microstructural changes with the composition. Electrochemical performance was evaluated by conventional methods such as cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The series of Ni-based catalysts demonstrated that after MM the composites integrate with oxides of the individual metallic materials without the formation of solid solutions. The electrocatalytic mass activities of the as-obtained composites were found in the following order: Ni0.80Co0.10Cu0.10/C (1181.14 A/g) ≅ Ni0.8Cu0.2/C (1124.45 A/g) > Ni0.80Co0.05Cu0.15/C (254.50 A/g) > Ni0.80Co0.15Cu0.05/C (209.34 A/g) > Ni0.8Co0.2/C (136.64 A/g). Among them, Ni0.80Co0.10Cu0.10/C showed the greatest stability and the leastwest charge transfer resistance that ranges between 0.28 and 0.80 Ω depending on the methanol concentration, and also presented activities higher than those of the commercial Pt/C catalysts. The results demonstrate that with this simple method, it is possible to modulate the electronic structure reducing CO poisoning on the surface of the catalysts and act as an alternative to replace high-cost noble metals during energy conversion from methanol.

Comparative analysis of brain age prediction using structural and diffusion MRIs in neonates

Using machine learning techniques to predict brain age from multimodal data has become a crucial biomarker for assessing brain development. Among various types of brain imaging data, structural magnetic resonance imaging (sMRI) and diffusion magnetic resonance imaging (dMRI) are the most commonly used modalities. sMRI focuses on depicting macrostructural features of the brain, while dMRI reveals the orientation of major white matter fibers and changes in tissue microstructure. However, their differential capabilities in reflecting newborn age and clinical implications have not been systematically studied. This study aims to explore the impact of sMRI and dMRI on brain age prediction. Comparing predictions based on T2-weighted(T2w) and fractional anisotropy (FA) images, we found their mean absolute errors (MAE) in predicting infant age to be similar. Exploratory analysis revealed for T2w images, areas such as the cerebral cortex and ventricles contribute most significantly to age prediction, whereas FA images highlight the cerebral cortex and regions of the main white matter tracts. Despite both modalities focusing on the cerebral cortex, they exhibit significant region-wise differences, reflecting developmental disparities in macro- and microstructural aspects of the cortex. Additionally, we examined the effects of prematurity, gender, and hemispherical asymmetry of the brain on age prediction for both modalities. Results showed significant differences (p<0.05) in age prediction biases based on FA images across gender and hemispherical asymmetry, whereas no significant differences were observed with T2w images. This study underscores the differences between T2w and FA images in predicting infant brain age, offering new perspectives for studying infant brain development and aiding more effective assessment and tracking of infant development.

Three-Dimensional Quantitative Analysis of Internal Limiting Membrane Peeling Related Structural Changes in Retinal Detachment Repair

PurposeTo assess macular microstructural changes associated with internal limiting membrane peeling (ILMP) using three-dimensional optical coherence tomography (3D-OCT) in primary macula-off rhegmatogenous retinal detachment (RRD) repairs with vitrectomy and silicone oil (SO) tamponade. DesignRetrospective, consecutive, interventional case series. MethodsSetting: Institutional practice. Patient Population: Patients who received primary RRD repair by a single experienced surgeon between January 2017 and December 2021. Main Outcome Measures: In the qualitative comparative analysis, the presence of macular changes among patients who underwent primary RRD repair with (21 eyes) or without ILMP (20 eyes) were observed. Subsequently, a detailed quantitative analysis of ILMP-related microstructural changes in 56 eyes using both 3D and 2D-OCT images were performed. ResultsIn the qualitative comparative analysis, macular microstructural changes were observed in 95% of ILMP eyes and 5% of non-ILMP eyes (p < 0.001). In the quantitative analysis, four major macular microstructural changes were detected: dimple (75%), dissociated nerve fiber layer (DONFL) (55%), ILM peeling edge thinning (IPET) (64%), and temporal macular groove (TMG) (23%). Dimples (n = 251, average 4.5 ± 5.8 per eye) could be further classified into type I (confined to the inner plexiform layer [IPL]; 73%) and type II (beyond IPL, 27%). The average depth of the deepest dimples was 58 ± 18 μm. The extent of IPET was 6.0 ± 3.7 clock hours. The average length of TMG was 1.8 ± 0.4 mm. Comparing to unoperated fellow eyes, the eyes after ILMP showed decreased inner temporal over nasal retinal thickness ratio (0.86 ± 0.07 versus 0.96 ± 0.03, p < 0.001), shorter disc-fovea distance (4.61 ± 0.32 µm versus 4.78 ± 0.37 µm, p = 0.041), and wider retinal vein trajectories (c’ = 2.48 ± 0.84 versus 3.39 ± 1.61, p = 0.002). ConclusionsMacular microstructural changes are common after ILMP in RRD repair, encompassing both focal changes (dimples, DONFL) and zonal changes (IPET, TMG). DONFL and dimples may be part of a continuum of findings stemming from the same mechanism. IPET and TMG are the results of macular tissue shift due to contracture of the optic disc and neurovascular bundle.

Diffusion tensor imaging in Behcet's disease with and without neurological involvement patients: evaluation of microstructural white matter abnormality with a tract-based spatial statistical analysis.

This study aims to assess the microstructural abnormalities in white matter (WM) among Behcet's disease (BD) patients, both with and without neurological involvement, utilising tract-based spatial statistics (TBSS) to elucidate the underlying causes of WM microstructural changes. This prospective study comprised 43 BD patients without neurological involvement, 15 neuro-Behcet's disease (NBD) patients with normal conventional MRI, and 54 healthy controls matched for age and sex. TBSS was applied in this diffusion tensor imaging study to conduct a whole-brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of WM. Compared to the control group, BD patients exhibited decreased FA and increased MD and RD in nearly all WM tracts, along with increased AD in the left corticospinal tract (CST), left inferior longitudinal fasciculus (ILF), and left superior longitudinal fasciculus (SLF). NBD patients also showed a widespread decrease in FA and increased MD and RD, similar to BD patients without neurological involvement. Additionally, NBD patients had increased AD in the left CST, left ILF, left SLF, left inferior fronto-occipital fasciculus (IFOF), and right CST. Compared to BD patients without neurological involvement, NBD patients exhibited a greater reduction in FA and an increase in MD and RD in WM tracts, with no significant differences in AD. These results suggest that the main mechanism of microstructural changes in the WM of BD patients may be related to impaired fibre integrity, demyelination, and decreased myelin sheath integrity. This study demonstrated BD patients without neurological involvement and NBD patients a decrease in FA and an increase in MD and RD were observed in larger areas of major WM tracts, while an increase in AD values was observed in fewer tracts. Our findings may be useful in understanding the pathophysiology underlying subclinical parenchymal involvement and neurological dysfunction in BD patients and the management of BD patients.

A NOVEL DOUBLE-SIDE LASER WELDED THICK PLATE: MICROSTRUCTURE AND NUMERICAL PREDICTION OF TENSILE TEST

The study aims to provide firsthand knowledge on finite element simulation (FES) of double-side laser welded (LW) stainless steel 304 (SS-304) thick plates used for automobile application. Double-side welding technique is an idea of achieving complete penetration with minimal heat input. The microstructural evaluation revealed the presence of dendritic growth that results in the enhancement of tensile strength (TS) for the welded sample. There is a slight increase in the delta ferrite content in weldment. The change in microstructure is due to thermal history during solidification. The TS of base metal (BM) was [Formula: see text][Formula: see text]MPa whereas the welded sample exhibited strength of [Formula: see text][Formula: see text]MPa. FES was successfully employed to simulate TS with error percentage less than 1.

Enhancing Heavy Metal Detection through Electrochemical Polishing of Carbon Electrodes.

Our research addresses the pressing need for environmental sensors capable of large-scale, on-site detection of a wide array of heavy metals with highly accurate sensor metrics. We present a novel approach using electrochemically polished (ECP) carbon screen-printed electrodes (cSPEs) for high-sensitivity detection of cadmium and lead. By applying a range of techniques, including scanning electron microscopy, energy-dispersive spectroscopy, Raman spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry, we investigated the impact of the electrochemical potential scan range, scan rate, and the number of cycles on electrode response and its ability to detect cadmium and lead. Our findings reveal a 41 ± 1.2% increase in voltammogram currents and a 51 ± 1.6% decrease in potential separations (n = 3), indicating a significantly improved active electrode area and kinetics. The impedance model elucidates the microstructural and electrochemical property changes in the ECP-treated electrodes, showing an 88 ± 2% (n = 3) decrease in the charge transfer resistance, leading to enhanced electrode electrical conductivity. A bismuth-reduced graphene oxide nanocomposite-modified, ECP-treated electrode demonstrated a higher cadmium and lead sensitivity of up to 5 ± 0.1 μAppb-1cm-2 and 2.7 ± 0.1 μAppb-1cm-2 (n = 3), respectively, resulting in sub-ppb limits of detection in spiked deionized water samples. Our study underscores the potential of optimally ECP-activated electrodes as a foundation for designing ultrasensitive heavy metal sensors for a wide range of real-world heavy metal-contaminated waters.

Drying kinetics of camellia oleifera seeds under hot air drying with ultrasonic pretreatment

Camellia oleifera seeds with high moisture content are prone to decay, leading to oil rancidity and seriously affecting subsequent processing and tea oil quality. Thus, an efficient drying method is needed. Hot air drying with ultrasonic pretreatment is a potential drying method for camellia oleifera seeds. In this paper, the effects of key parameters such as ultrasound power, ultrasound pretreatment time, and hot air drying temperature on the moisture ratio of camellia oleifera seeds, as well as the changes in microstructure of both seed shell and seed kernel, and the main quality parameters such as peroxide value and acid value of tea oil were explored. Results showed that the shorter the ultrasound pretreatment time, the greater the ultrasound power, the higher the temperature, the faster the drying rate, and the shorter the drying time. The drying time and specific energy consumption was reduced by up to 26.7 % and 16.8 % with the ultrasonic pretreatment, respectively. The optimal ultrasonic pretreatment time is 2 min, and the ultrasonic power is 300 W. A Genetic Algorithm Optimized Backpropagation Artificial Neural Network (GA-BP-ANN) drying model was proposed to predict the changes in moisture ratio during the drying process of camellia oleifera seeds to provide guidance for the development of intelligent drying system. The experimental results showed that the proposed drying model had a good predictive performance, with an RMSE of 0.0076969 and an R2 of 99.909 %, which can accurately estimate the effect of ultrasonic pretreatment on hot air drying. The research results of this study are expected to reduce post-harvest losses of camellia oleifera fruits and provide theoretical support for the development of drying systems of camellia oleifera seeds and similar agricultural products.

Cognitive Impairment in Cerebral Small Vessel Disease Is Associated with Corpus Callosum Microstructure Changes Based on Diffusion MRI.

to evaluate microstructural changes in the corpus callosum (CC) using diffusion MRI (D-MRI) approaches in cSVD patients with different severity of CI and reveal the most sensitive correlations of diffusion metrics with CI. the study included 166 cSVD patients (51.8% women; 60.4 ± 7.6 years) and 44 healthy volunteers (65.9% women; 59.6 ± 6.8 years). All subjects underwent D-MRI (3T) with signal (diffusion tensor and kurtosis) and biophysical (neurite orientation dispersion and density imaging, NODDI, white matter tract integrity, WMTI, multicompartment spherical mean technique, MC-SMT) modeling in three CC segments as well as a neuropsychological assessment. in cSVD patients, microstructural changes were found in all CC segments already at the subjective CI stage, which was found to worsen into mild CI and dementia. More pronounced changes were observed in the forceps minor. Among the signal models FA, MD, MK, RD, and RK, as well as among the biophysical models, MC-SMT (EMD, ETR) and WMTI (AWF) metrics exhibited the largest area under the curve (>0.85), characterizing the loss of microstructural integrity, the severity of potential demyelination, and the proportion of intra-axonal water, respectively. Conclusion: the study reveals the relevance of advanced D-MRI approaches for the assessment of brain tissue changes in cSVD. The identified diffusion biomarkers could be used for the clarification and observation of CI progression.

Oxidation and compositional modulation in single phase C14 Zr0.6Ti0.4Fe1Cr1 alloy

This study investigates the effects of heat treatment on the crystal structure and hydrogen absorption behavior of the AB2 type metal hydride Zr0.6Ti0.4Fe1Cr1. The objective is to understand how 3- and 6-day heat treatments at 1000°C influence the alloy's microstructure and hydrogenation properties. Using electron microscopy, EBSD analysis, X-ray diffraction, and hydrogenation measurements, we found that the as-cast alloy exhibits rapid hydrogen absorption with significant compositional variations due to segregation during casting, confirmed by a single C14 Laves phase in XRD. Heat treatment slowed hydrogen absorption and reduced hydrogen capacity, with XRD indicating the structure remained primarily C14 Laves phase. However, SEM/EDS analysis showed substantial microstructural changes, including the emergence of new phases and segregation of Zr-rich phases, likely non-hydride forming, influenced by elevated oxygen content. These new phases probably contribute to the reduced hydrogen uptake capacity.