Homogeneous Texture Research Articles

Modeling shallow soil moisture dynamics in mountainous landslide active regions

Under the worsening climate change, the mountainous landslide active regions are more likely to suffer severe disasters threatening residents. To predict the occurrence of landslides, shallow soil moisture lying in the interface of the hydrological processes has been found as one of the critical factors. However, shallow soil moisture data are often scarce in the landslide active regions. To overcome the severe measurement deficiencies and provide predictions of soil moisture dynamics, we construct a physically-based shallow soil moisture model based on the assumptions of ideal flow, homogeneous and isotropic soil textures, and 1-dimensional water movement dominant by gravity forces. In the model, the meteorological conditions and the physical soil properties are taken into consideration. With limited field measurements, the model can provide reasonably accurate soil moisture predictions. In recognition of the seasonal weather characteristics, we perform a series of sensitivity analyses to examine the response of shallow soil moisture and relate the hydrological processes to air temperature, precipitation intensity, duration, and combinations thereof. Complex interactions of hydrological processes are found with variations in precipitation and air temperature, depending on the interlinked boundary conditions of the soil and water. It demonstrates a strong need for a decent forecast of the complex shallow soil moisture dynamics and the associated hydrologic processes in mountain regions to cope with climate change for landslide preparation and agricultural adaptation in the future.

Ore‑forming process revealed by sphalerite texture and geochemistry: A case study at the Kangjiawan Pb–Zn deposit in Qin-Hang Metallogenic Belt, South China

The origin of the abundant hydrothermal vein-type Pb–Zn deposits in the Qin-Hang Metallogenic Belt (QHMB) in South China remains disputed due to the poor constraints on the ore-forming process. The Kangjiawan (1.96 Mt @ 4.70% Zn and 6.02% Pb), is a representative Pb–Zn deposit in the central QHMB, and its mineralization can be divided into three stages: (I) pre-ore quartz-pyrite, (II) main-ore quartz-pyrite-galena-sphalerite, and (III) Late ore calcite-pyrite-galena-sphalerite. Stage II sphalerite (Sp2) commonly coexists with pyrite and chalcopyrite, and shows a homogeneous internal texture. Stage III sphalerite (Sp3) comprises two generations of sphalerite, namely the earlier, texturally homogeneous Sp3a (coexists with “chalcopyrite disease”), and the younger Sp3b that replaced Sp3a and coexists with galena.Sp2 is Fe-Mn-Co-In-rich, and characterized by the high In/Ga (avg. 2.6) and Zn/Cd (avg. 242.0), but low Zn/Fe (avg. 12.2) ratios, suggesting high ore-forming temperature, consistent with the results of the sphalerite GGIMFis geothermometer (307–314 ℃ with an average of 310 ℃). Sp3a has higher Se, Co, and Ni contents than Sp3b, implying the possible decline of temperature from Sp3a to Sp3b. Meanwhile, the Kangjiawan sphalerite geochemistry suggests a decreasing trend of fS2 from Sp2 (lg fS2 = − 10.5 to − 12.4) to Sp3 (lg fS2 = − 17.2 to − 20.3). These results indicate a dramatic change in the temperature and fS2 from the main-ore to the late-ore stage, probably caused by the mixing between meteoric water and magmatic-hydrothermal fluids in Stage III, as supported by published HO isotope data. The ubiquitous hydrothermal breccias with fine-grained pyrite cement suggest fluid boiling in Stage II. The Kangjiawan sphalerite geochemistry is similar to that of skarn-type sphalerite, consistent with the close spatial–temporal link between the Kangjiawan mineralization and the Shuikoushan granodiorite stock. Therefore, we inferred that the Kangjiawan is a Pb–Zn skarn deposit genetically related to the Shuikoushan granodiorite, with the ore precipitation caused by fluid boiling and meteoric water incursion.

Radiomic study on preoperative multi-modal magnetic resonance images identifies IDH-mutant TERT promoter-mutant gliomas.

Gliomas with comutations of isocitrate dehydrogenase (IDH) genes and telomerase reverse transcriptase (TERT) gene promoter (IDHmut pTERTmut) show distinct biological features and respond to first-line treatment differently in comparison with other gliomas. This study aimed to characterize the IDHmut pTERTmut gliomas in multimodal MRI using the radiomic method and establish a precise diagnostic model identifying this group of gliomas. A total of 140 patients with untreated primary gliomas were admitted between 2016 and 2020 to West China Hospital as a discovery cohort, including 22 IDHmut pTERTmut patients. Thirty-four additional cases from a different hospital were included in the study as an independent validation cohort. A total of 3654 radiomic features were extracted from the preoperative multimodal MRI images (T1c, FLAIR, and ADC maps) and filtered in a data-driven approach. The discovery cohort was split into training and test sets by a 4:1 ratio. A diagnostic model (multilayer perceptron classifier) for detecting the IDHmut pTERTmut gliomas was trained using an automatic machine-learning algorithm named tree-based pipeline optimization tool (TPOT). The most critical radiomic features in the model were identified and visualized. The model achieved an area under the receiver-operating curve (AUROC) of 0.971 (95% CI, 0.902-1.000), the sensitivity of 0.833 (95% CI, 0.333-1.000), and the specificity of 0.966 (95% CI, 0.931-1.000) in the test set. The area under the precision-recall curve (AUCPR) was 0.754 (95% CI, 0.572-0.833) and the F1 score was 0.833 (95% CI, 0.500-1.000). In the independent validation set, the model reached 0.952 AUROC, 0.714 sensitivity, 0.963 specificity, 0.841 AUCPR, and 0.769 F1 score. MR radiomic features of the IDHmut pTERTmut gliomas represented homogenous low-complexity texture in three modalities. An accurate diagnostic model was constructed for detecting IDHmut pTERTmut gliomas using multimodal radiomic features. The most important features were associated with the homogenous simple texture of IDHmut pTERTmut gliomas in MRI images transformed using Laplacian of Gaussian and wavelet filters.

In-situ U[sbnd]Pb geochronology of vesuvianite in skarn deposits

The timing of hydrothermal activity is a key factor in any predictive genetic model of skarn mineralization, but direct dating is often hindered by the absence of suitable minerals to date. Vesuvianite, a common mineral in skarn deposits, can incorporate U and has a high Pb closure temperature (>650 °C), and consequently may be suitable for dating for skarn deposits. Vesuvianite collected from nine Chinese skarn deposits, including the Jinchuantang SnBi, Shizhuyuan W–Sn–Mo–Bi polymetallic, Jiepai CuW, Dashunlong Sn, Xianghualing Sn, Furong Sn, and Huangshaping W–Sn–Mo–Cu polymetallic deposits in Nanling Range (Southern China), and the Kaerqueka and Saishitang Cu deposits in East Kunlun Orogen (Northwestern China), have high U concentrations (median 66.8 ppm for 460 LA-ICP-MS analysis spots). The flat and stable time-resolved signal spectra for U during LA-ICP-MS analysis, combined with the absence of nanoscale mineral inclusions, porosities, or lattice defects in the JCT vesuvianite, with high and consistent U concentrations, revealed by the HAADF-STEM images, and the marked positive relationships between U and REE collectively suggest that the U incorporation into vesuvianite was primarily controlled by replacement of Ca2+ in eight-fold coordination, confirming that vesuvianite may be a suitable UPb geochronometer. The JCT vesuvianite is characterized by high and consistent U concentrations (260–526 ppm, median 307 ppm) and homogeneous internal texture and elemental distribution, and yields an ID-TIMS UPb concordia age (2σ, 153.9 ± 0.2 Ma, MSWD = 1.6, n = 11), demonstrating that it can be taken as a potential LA-ICP-MS UPb reference material, which can be freely distributed to other laboratories. Using the JCT vesuvianite as a UPb reference material, the Kaerqueka, Saishitang, Jiepai, Dashunlong, Xianghualing, Furong, and Shizhuyuan vesuvianite yielded well-defined LA-ICP-MS UPb ages (239.0–152.1 Ma, 2σ), consistent with previously published age constraints of mineralization and cogenetic igneous rocks. Vesuvianite from the Huangshaping W–Sn–Mo–Cu polymetallic deposit, yielded UPb ages of 157.3 ± 1.4 Ma (2σ, MSWD = 1.8) and 161.0 ± 1.3 Ma (2σ, MSWD = 1.9), providing reliable constraints on the overprinting sequence of the skarn W–Sn–Mo and Cu mineralization events at Huangshaping, which was not previously detectable using other mineralization chronometers. Combined, these ages suggest that vesuvianite is a robust and reliable geochronometer, and offers a new tool for dating skarn deposits.

Chemistry and U–Pb geochronology of cassiterite in the Xiasai deposit, central Yidun Terrane (SW China): Link between Sn and Ag–Pb–Zn mineralisation

Tin and (Ag)–Pb–Zn mineralisation generally co-exist in SEDEX, porphyry, skarn, greisen, as well as magmatic-hydrothermal Sn and/or Pb–Zn polymetallic deposits. The genetic relationship between these two styles of mineralization, however, is not well defined. More than 20 skarn and hydrothermal-vein-type Ag–Pb–Zn–Sn deposits can be found in the central Yidun Terrane (YDT) of southwestern China. Amongst these is the large Xiasai deposit, which contains 1028 t Ag @ 337.8 g/t, 0.27 Mt Pb + Zn @ 8.33 %, and 20,000 t Sn @ 0.75 %. The deposit is zoned, comprising proximal cassiterite-quartz veins and distal Ag–Pb–Zn veins. We present micro-textural studies, LA–ICP–MS U–Pb dating results, as well as cassiterite major and trace element data that served to better constrain the link between the Sn and Ag–Pb–Zn mineralisation at Xiasai. Two types of cassiterite, i.e., Cst I and Cst II, can be distinguished using cathodoluminescence (CL) imagery. Cst I has a dull luminesce and oscillatory zonation, and it has been partially replaced by Cst II, which has a bright luminesce and a homogeneous texture. Whistle the SnO2 and TiO2 contents of Cst I and Cst II are similar, the latter has slightly higher FeO compositions (from bdl to 0.08 wt% and 0.01 to 0.11 wt%, respectively). LA–ICP–MS U–Pb dating of cassiterite yielded a Tera-Wasserburg U–Pb lower intercept age of 99.2 ± 0.8 Ma (n = 39, MSWD = 1.8), identical to the ages of granitic magmatism and Ag–Pb–Zn vein formations. LA–ICP–MS trace element analyses revealed that cassiterite is enriched in Ti and W, but depleted in Fe, Mn, Nb, and Ta. The Zr/Hf ratios of cassiterite range from 4.7 to 15.8 and Ti/Zr ratios range from 1.8 to 6.2. Overall, the measured Fe, W, Nb, and Ta concentrations, as well as the calculated Zr/Hf and Ti/Zr ratios, indicate that the cassiterite-quartz veins at Xiasai have a magmatic-hydrothermal origin. Our findings, when combined with previous micro-thermometrical fluid inclusion data (423–481 °C for Sn and 158–386 °C for Ag–Pb–Zn mineralisation), suggest that Sn and Ag–Pb–Zn mineralisation was cogenetic and linked to a common magmatic-hydrothermal system. The spatial relationship between Cretaceous A-type granitic magmatism and Ag–Pb–Zn–Sn mineralisation in the central YDT can be used as a guideline for mineral exploration of both skarn and hydrothermal veins.

A novel factor graph-based optimization technique for stereo correspondence estimation

Dense disparities among multiple views are essential for estimating the 3D architecture of a scene based on the geometrical relationship between the scene and the views or cameras. Scenes with larger extents of homogeneous textures, differing scene illumination among the multiple views and with occluding objects affect the accuracy of the estimated disparities. Markov random fields based methods for disparity estimation address these limitations using spatial dependencies among the observations and among the disparity estimates. These methods, however, are limited by spatially fixed and smaller neighborhood systems or cliques. Recent learning-based methods generate rich set of stereo features for generating cost volume and estimating disparity. In this work, we present a new factor graph-based probabilistic graphical model for disparity estimation that allows a larger and a spatially variable neighborhood structure determined based on the local scene characteristics. Our algorithm improves the accuracy of disparity estimates in stereo image pairs with varying texture and illumination characteristics by enforcing spatial dependencies among scene characteristics as well as among disparity estimates. We evaluated our method using the Middlebury benchmark stereo datasets and the Middlebury evaluation dataset version 3.0 and compared its performance with recent state-of-the-art disparity estimation algorithms. Our factor graph-based algorithm provided disparity estimates with higher accuracy when compared to the recent non-learning- and learning-based disparity estimation algorithms. The factor graph formulation can be used for obtaining maximum a posteriori estimates from models or optimization problems with complex dependency structure among hidden variables. The strategies of using a priori distributions with shorter support and spatial dependencies were useful for reducing the computational cost and improving message convergence in the model. The factor-graph algorithm is also useful for other dense estimation problems such as optical flow estimation.

Physical Stability and Antioxidant Activity of Pee-Off Gel Mask Ethanol Extract of Buas-buas Leaf (Premna serratifolia L.)

This study aims to determine the physical stability and antioxidant activity of peel-off gel mask ethanol extract of buas-buas leaf (Premna serratifolia L.). The ethanol extract of buas-buas leaves was obtained by maceration using 70% ethanol solvent, then concentrated using a rotary evaporator to get a thick extract. Formulation EEDB into a peel-off gel mask with a concentration of each EEDB (FI: 1%, FII: 2%, FIII : 3%). The EEDB peel-off gel mask formula was tested for physical stability by cycling test method using a climatic chamber at a temperature of 40°C ± 2°C and 4°C ± 2°C for six cycles. The tests included organoleptic, homogeneity, viscosity, pH, spreadability, and drying time. An antioxidant test was carried out using the DPPH method. The results of the physical stability test on the three EEDB peel-off gel mask formulas (FI: 1%, FII: 2%, FIII: 3%) showed good physical stability because there was no significant difference during six storage cycles (P>0.05) with the results of the preparation have a characteristic aroma of oleum citri, brownish-green in color, have a thick, homogeneous texture, meet the requirements of pH, viscosity, spreadability, and drying time. The stability test results of the antioxidant activity of the peel-off gel mask EEDB in the three formulas showed no significant change (P>0.05). The antioxidant activity during six storage cycles with the highest average percent inhibition before and after the cycling test, namely in Formula III, was 77.20 ± 0.28%.

Differentiated enrichment of magnetite in the Jurassic W–Sn and Cu skarn deposits in the Nanling Range (South China) and their ore-forming processes: An example from the Huangshaping deposit

Abundant Jurassic magnetite-rich W–Sn and magnetite-poor Cu skarn deposits were discovered in the Nanling Range of South China. However, their ore-forming processes and the mechanism of differentiated magnetite enrichment are still poorly constrained. The Huangshaping represents a typical skarn deposit in the Nanling Range, which developed both W–Mo–Sn and Cu mineralization systems, providing a good window to address this issue. In the Huangshaping W–Mo–Sn system, abundant magnetite was formed in three generations (Mag-1, Mag-2, and Mag-3). Mag-1 shows core (Mag-1c)-mantle (Mag-1 m)-rim (Mag-1r) texture, with abundant nano-inclusions trapped in the oscillatory-zoned Mag-1 m. Porous Mag-2 replaced Mag-1 along sharp and irregular boundaries, and both Mag-1 and Mag-2 were replaced by cassiterite. Mag-3 occurred along with quartz-bismuthinite veins and also replaced Mag-1. Magnetite-4 (Mag-4) has a homogeneous texture and occurs locally in the Huangshaping Cu system. The mineral assemblage, texture, and geochemistry suggest a hydrothermal origin for all these magnetite types and possible magmatic-hydrothermal pulses in the W-Mo-Sn system. The first magmatic-hydrothermal pulse was likely associated with granite porphyry and formed Mag-1 in a closed system with increasing oxygen fugacity (fO2) and decreasing concentrations of trace elements. The abundant nano-inclusions in Mag-1 m suggest probable local supersaturation of trace elements in the magnetite-fluid interface. The irregular contact, porosities, and lower trace element concentrations (e.g., Mg, Al, Si, Ca, and Mn) of Mag-2 reveal that it may have formed via the dissolution and reprecipitation process (DRP) of Mag-1. This process was possibly controlled by decreasing fO2. The second magmatic-hydrothermal pulse derived from the granite porphyry may have formed Mag-3, evidenced by the increasing temperature, decreasing fO2, and high trace element concentrations (e.g., Mg, Al, Si, Ca, and Mn). In the Cu system, the quartz porphyry-derived ore fluid may have formed Mag-4 under lower temperature and fO2 than in the W–Mo–Sn system. Besides, we suggested that the paucity of magnetite in these Jurassic Cu skarn deposits of the Nanling Range was likely caused by the low Fe concentration in the ore-related magma, genetically associated with the amphibole fractionation during the magma formation. This may respond to the extensional formation environment of Jurassic Cu and W–Sn skarn deposits in the Nanling Range, caused by the asthenosphere upwelling linked to the Paleo-Pacific subduction.

Fluid origin and critical ore-forming processes for the giant gold mineralization in the Jiaodong Peninsula, China: Constraints from in situ elemental and oxygen isotopic compositions of quartz and LA–ICP–MS analysis of fluid inclusions

The Jiaodong Peninsula, China, is one of the largest gold provinces in the world. During a short time interval in the Early Cretaceous, over 5000 t of gold were accumulated there. The mechanisms controlling the focused Au deposition and the origins of massive amounts of auriferous fluids are still controversial. Quartz–sulfide lode mineralization (Linglong-type) and disseminated/stockwork mineralization (Jiaojia-type) are the two major mineralization styles in the Jiaodong Peninsula. Herein, we conducted in situ textural, elemental and oxygen isotopic analyses using scanning electron microscopy (SEM), laser ablation-inductively coupled plasma-mass spectrometry (LA–ICP–MS) and secondary ion mass spectrometry (SIMS) on quartz from different hydrothermal stages and depths for three representative Linglong-type (Linglong deposit) and Jiaojia-type (Xiadian and Jiangjiayao deposits) gold deposits in the northwestern Jiaodong Peninsula, with the aim to constrain the ore-forming processes. The LA–ICP–MS analysis of individual fluid inclusions was also conducted to unravel the origin of the auriferous fluids. The results show that from the pre-mineralization to the ore-forming stages in the Linglong-type mineralization, the homogenization temperatures and salinities of fluid inclusions and the δ18Oquartz values change slightly, but the Al concentrations of quartz decrease continuously. Combined with the coexistence of CO2- and H2O-rich fluid inclusion endmembers, these trends indicate the increase of pH induced by CO2 degassing (fluid–fluid unmixing), which led to focused Au deposition. The quartz grains from the Jiaojia-type mineralization typically show a homogeneous texture with well-correlated lithophile elements (e.g., K, Al and Rb), which are distinct from those of the Linglong-type that are characterized by oscillatory zoning with much higher Al concentrations and δ18Oquartz values. These phenomena indicate that enhanced fluid–rock interaction occurred in the Jiaojia-type mineralization. In addition, the δ18Oquartz values show an increase from deep to shallow depths. In combination with thermodynamic modelling, it suggests decreasing fluid–rock interaction with decreasing depth. The above results corroborate that multiple mechanisms led to the efficient Au deposition in the Jiaodong Peninsula. Fluid–fluid unmixing typically occurred in the Linglong-type mineralization, while fluid–rock interaction was dominant in the Jiaojia-type mineralization. The different mechanisms might render mining challenging due to the changeable locations of favorable Au unloading.The LA–ICP–MS results of fluid inclusions suggest that the ore-forming fluids are metamorphic fluids rather than magmatic–hydrothermal fluids. In combination with the isotopic compositions of ores showing considerable mantle affinities and large-scale mafic underplating occurring beneath the study region, we propose a new genetic model that accounts for the origin of the auriferous fluids. The new model invokes the devolatilization of previously emplaced H2O- and Au-rich amphibole cumulates through amphibolite- to granulite-facies metamorphism in the middle–lower crust. It suggests an alternative way to generate the ‘orogenic-like’ gold deposits.

Developing a homogeneous texture dish by combining solid and liquid foodstuff matrices

A dish with a uniform texture was developed for people with a poor oral health problem: dysphagia. Its texture and color were studied, along with its consumption and cold storage with reheating. The dish was constituted by softening carrot and integrated into thickened soup. Carrot was softened by applying enzymes via freeze-thaw impregnation (FI). Soup was thickened by guar gum. The results indicate both components achieved a similar texture. Firmness and cohesiveness increased significantly as temperature dropped. Judges were unable to detect the presence or absence of carrot in the dish by a sensorial compression assay, but could detect color changes. These outcomes were also verified by a digital image analysis. The results demonstrate the feasibility of using FI treatment combined with enzymes to soften vegetables and subsequently incorporating them into thickened liquid foodstuff to develop safe, sensory-accepted and texture-modified products for specific populations.

Evaluation of potentially probiotic yeasts and Lactiplantibacillus plantarum in co-culture for the elaboration of a functional plant-based fermented beverage

This work aimed to evaluate the performance of co-cultivation of potential probiotic yeast and lactic acid bacteria (LAB) in producing plant-based fermented beverages. The co-culture comprised LAB Lactiplantibacillus plantarum CCMA0743 with the yeasts Pichia kluyveri CCMA 0615, Pichia guilliermondii CCMA 1753 and Debaryomyces hansenii CCMA 1761 separately. The plant substrate was 75 g oat, 175 g sunflower seeds, and 75 g almonds. The viability of microorganisms in the plant-based matrix was evaluated during fermentation, storage at 4 °C, and under simulated gastrointestinal tract (GIT) conditions. Chemical analysis, antioxidant activity, and sensory profile of the beverages were also determined. The three yeasts and the LAB showed counts greater than 6.0 log CFU/mL after fermentation, and the plant-based matrix protected the yeasts during simulated digestion. P. kluyveri and D. hansenii showed higher survival than P. guilliermondii and L. plantarum after exposure to simulated GIT conditions. The pH of the plant-based matrix reduced from approximately 7 to 3.8. Lactic acid was the main organic acid produced during fermentation. In addition, 113 volatile compounds were detected by gas chromatography-mass spectrometry (GC–MS), including alcohols, aldehydes, alkanes, alkenes, acids, ester, ether, ketones, phenol, and amides. The beverage sensory profile varied with the co-culture. The co-culture D. hansenii and L. plantarum showed higher antioxidant activity than the other co-culture tested, and the homogeneous texture attribute characterized the beverage produced with this combination. Results show the suitability of tested co-cultures to produce a plant-based fermented beverage and indicate more significant potential for D. hansenii and L. plantarum co-culture as a starter for its functionalization.

Pengaruh Penambahan Monosodium Fosfat pada Pembuatan Processed Cheese dengan Koagulan Sari Nanas terhadap Kadar Air, Rendemen, dan Akseptabilitas

Processed cheese is a natural cheese that has undergone further processing to produce a more homogeneous texture. Bromelain enzyme derived from pineapple fruit which was used as a coagulant. Emulsifier in the form of monosodium phosphate (NaH 2 PO 4 ) was used as an emulsifier. This study was aimed to determine the effect of the NaH 2 PO 4 addition on moisture content, yield, and acceptability of processed cheese with pineapple juice coagulant. This research was conducted by experimental method using a completely randomized design with a significance level of 5% for 3 treatment concentrations (P1=2%, P2-3%, and P3=4%). Each treatment was repeated 6 times. If there was a difference, Duncan’s further test is carried out. Acceptability data was tested using Kruskal-Wallis, if there was a difference, the Mann-Whitney further test was carried out. The results showed that the use of NaH2PO4 with concentration of P1 (2%), P2 (3%) and P3 (4%) had no effect on moisture content and yield. The best acceptability value was found in P2 (3%) with a numerical scale for the best taste, namely 3.67 (slightly like-like), color 3.73 (slightly like-like), aroma 4.27 (like-like very much), texture 3.60 (slightly like-like), and the total acceptance is 3.53 (slightly like-like).

Formulation of Semi Solid Lip Dying From Extract Areca Seeds (Areca Catechu L.) With Several Concentrations

Areca nut (Areca catechu L.) is a natural dye as a substitute for synthetic dyes which are less safe for skin health. This study aims to make a semi-solid form of lip color cosmetic preparations with several concentrations. Extracts was made by soaking the powder using 96% ethanol.The results of this reseach is that the lip color has a vanilla smell, soft and homogeneous texture, visually brown color, pH 6.00 to 6.50. Melting point between 41 – 440C Color release test or smear test for a 40% concentration formula shows a good and homogeneous color. Chemical test results using a chromameter formula 20% 0HUE 34.87 (red), 30% 23.10 (red) and 40% 15.03 (purple red)

Electrospun alginate mats embedding silver nanoparticles with bioactive properties

Polysaccharide-based composites embedding silver nanoparticles (AgNPs) represent a promising alternative to common antimicrobial materials because of the effective, broad-spectrum biocidal properties of AgNPs combined with the biocompatibility and environmental safety of the naturally occurring polymeric component. In this work, AgNPs stabilized with alginate chains (Alg@AgNPs) were successfully synthesized in situ within the polysaccharide solution through a wet chemical approach carried out at different concentrations of the silver salt precursor. Once obtained, the aqueous suspensions were electrospun to prepare non-woven membranes, showing a homogeneous nanostructured texture (with fiber diameter between 100 and 150 nm), which was found to be influenced by the size (between 20 and 35 nm) of the embedded metal nanoparticles.The biocidal potential of the nanocomposite mats was preliminarily tested against Gram-negative E. coli. The results showed that the antimicrobial response of the investigated samples occurred within a day of incubation and can be observed for AgNPs content in the polysaccharide fibers far below the nanomolar regime.

Deformation of Polycrystalline MgO Up to 8.3 GPa and 1270 K: Microstructures, Dominant Slip-Systems, and Transition to Grain Boundary Sliding

Ferropericlase is the second most abundant mineral in the Earth’s lower mantle and its mechanical properties have a strong influence on the rheology of this region. Here, we deform polycrystalline MgO, the magnesium end-member of ferropericlase, at conditions ranging from 1.6 to 8.3 GPa and 875–1,270 K. We analyse the flow laws and microstructures of the recovered samples using electron microscopy and compare our observations with predictions from the literature. We identify a first mechanism for samples deformed at 1,270 K, attributed to a regime controlled by grain boundary sliding accommodated by diffusion, and characterized by a small grain size, an absence of texture, and no intracrystalline deformation. At 1,070 K and below, the deformation regime is controlled by dislocations. The samples show a more homogeneous grain size distribution, significant texture, and intracrystalline strains. In this regime, deformation is controlled by the ⟨110⟩{110} slip system and a combined ⟨110⟩{110} and ⟨110⟩{100} slip, depending on pressure and temperature. Based on these results, we propose an updated deformation map for polycrystalline MgO at mantle conditions. The implications for ferropericlase and seismic observations in the Earth’s lower mantle are discussed.

Fluid-attenuated inversion recovery magnetic resonance imaging textural features as sensitive markers of white matter damage in midlife adults

White matter hyperintensities are common radiological findings in ageing and a typical manifestation of cerebral small vessel disease. White matter hyperintensity burden is evaluated by quantifying their volume; however, subtle changes in the white matter may not be captured by white matter hyperintensity volumetry. In this cross-sectional study, we investigated whether magnetic resonance imaging texture of both white matter hyperintensities and normal appearing white matter was associated with reaction time, white matter hyperintensity volume and dementia risk in a midlife cognitively normal population. Data from 183 cognitively healthy midlife adults from the PREVENT-Dementia study (mean age 51.9 ± 5.4; 70% females) were analysed. White matter hyperintensities were segmented from 3 Tesla fluid-attenuated inversion recovery scans using a semi-automated approach. The fluid-attenuated inversion recovery images were bias field corrected and textural features (intensity mean and standard deviation, contrast, energy, entropy, homogeneity) were calculated in white matter hyperintensities and normal appearing white matter based on generated textural maps. Textural features were analysed for associations with white matter hyperintensity volume, reaction time and the Cardiovascular Risk Factors, Aging and Dementia risk score using linear regression models adjusting for age and sex. The extent of normal appearing white matter surrounding white matter hyperintensities demonstrating similar textural associations to white matter hyperintensities was further investigated by defining layers surrounding white matter hyperintensities at increments of 0.86 mm thickness. Lower mean intensity within white matter hyperintensities was a significant predictor of longer reaction time (t = −3.77, P < 0.01). White matter hyperintensity volume was predicted by textural features within white matter hyperintensities and normal appearing white matter, albeit in opposite directions. A white matter area extending 2.5 – 3.5 mm further from the white matter hyperintensities demonstrated similar associations. White matter hyperintensity volume was not related to reaction time, although interaction analysis revealed that participants with high white matter hyperintensity burden and less homogeneous white matter hyperintensity texture demonstrated slower reaction time. Higher Cardiovascular Risk Factors, Aging, and Dementia score was associated with a heterogeneous normal appearing white matter intensity pattern. Overall, greater homogeneity within white matter hyperintensities and a more heterogeneous normal appearing white matter intensity profile were connected to a higher white matter hyperintensity burden, while heterogeneous intensity was related to prolonged reaction time (white matter hyperintensities of larger volume) and dementia risk (normal appearing white matter). Our results suggest that the quantified textural measures extracted from widely used clinical scans, might capture underlying microstructural damage and might be more sensitive to early pathological changes compared to white matter hyperintensity volumetry.

Effect of Mg Doping on the Physical Properties of Fe2O3 Thin Films for Photocatalytic Devices.

Undoped and Mg-doped (y = [Mg2+]/[Fe3+] = 1, 2, 3, and 4 at.%) Fe2O3 thin films were synthesized by a simple spray pyrolysis technique. The thin films were extensively characterized. X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) analysis confirmed the successful insertion of Mg in the rhombohedral structure of Fe2O3. In addition, scanning electronic microscope (SEM) and confocal microscope (CM) images showed a homogenous texture of the film, which was free of defects. The rough surface of the film obtained by spray pyrolysis is an important feature for photocatalysis and gas sensor applications. The direct band gap of the doped Fe2O3 films obtained for [Mg2+]/[Fe3+] = 3 at.% was Edir = 2.20 eV, which recommends the Mg-doped iron oxide as an optical window or buffer layer in solar cell devices. The photodegradation performance of Mg-doped Fe2O3 was assessed by studying the removal of methylene blue (MB) under sunlight irradiation, with an effective removal efficiency of 90% within 180 min. The excellent photodegradation activity was attributed to the strong absorption of Mg-doped Fe2O3 in the UV and most of the visible light, and to the effective separation of photogenerated charge carriers.

Fabrication and Characterization of Transparent and Uniform Cellulose/Polyethylene Composite Films from Used Disposable Paper Cups by the "One-Pot Method".

Disposable paper cups are usually composed of high-grade paper board and an inner polyethylene coatings and are extensively used in daily life. However, most disposable paper cups are only used for a short time and then incinerated or accumulated in landfill at the end of their service due to the difficulty in separating the components, leading to a serious threat to our ecosystem. Therefore, developing a facile and green method to recycle and reuse disposable paper cups is vital. By using ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl) as a solvent, transparent and homogenous cellulose/polyethylene composite films were successfully prepared from used bamboo-based disposable paper cups through the “one-pot method”, without any pre-treatment. It was found that there was a transformation of cellulose I to II after the dissolution and regeneration processes, and the crystallinity degree of the regenerated cellulose-based materials decreased significantly, resulting in a change in thermal properties. Meanwhile, compared to traditional pure cellulose films, the composite films possessed good UV-shielding properties and hydrophobicity. Moreover, they also displayed good mechanical properties. Additionally, the size of the ground PE coatings displayed obvious effects on the structures and properties of the composite films, where the CPE100 (sieved with 100–200 mesh) possessed the most homogeneous texture and the highest tensile strength (82 Mpa), higher than that of commercial polyethylene film (9–12 MPa), showing superiority as packaging or wrapping materials. Consequently, the goals to fabricate uniform cellulose/polyethylene composite films and valorize the solid waste from disposable paper cups were simultaneously achieved by a facile and green “one-pot method”.

Effect of Residual Deformation Energy and Critical Heating Rate on Cubic Texture and Grain Growth Behavior of Severely Deformed Aluminum Foil.

To clarify the microstructure, grain size, and recrystallization behavior during different annealing processes with controlled heating rates, the aim of this study was to investigate the effect of residual deformation energy after cold rolling and critical heating rate on cubic texture components, and grain growth behavior of aluminum plate, which was subjected to severe deformation. The experimental results revealed that the stored energy can be inferred from a calculation that fast annealing (FA) for 30 s was 2.2 times as large as slow annealing (SA) at 320 °C, which provided the driving force for grain growth during subsequent heating and resulted in a significant coarsening of grains in the FA process. In contrast, the intensity of cubic texture in SA was significantly higher than that in the FA process. A critical heating rate of 50 °C/min had been obtained to produce a homogeneous microstructure and strong cubic texture during the annealing processes with controlled heating rates and was verified by experiment. The relationship of Δηsur > 0.02ηb was as a criterion used to determine whether abnormal grain growth happened in aluminum foil, while the grain size exceeded the thickness of aluminum foil by examined calculation.

Microstructural evolution of a niobium-microalloyed steel during hot shear deformation and subsequent cooling

For the purpose of obtaining a niobium-microalloyed steel with a preferable ultrafine-grained ferrite microstructure, a thermomechanical controlled processing (TMCP) strategy that included a hot shear deformation conducted near the local phase transformation temperature and a subsequent cooling process is proposed. As a large plastic strain was enforced by the simple hot shear deformation, severe plastic deformation (SPD) of the niobium-microalloyed steel was realized. The proposed TMCP strategy was simulated physically on a Thermecmastor-Z compression machine combined with a multi-type cooling system. Various cooling rates of different cooling methods resulted in reconstructive and displacive phase transformations from γ-Fe to α-Fe and led to different microstructural morphologies. In addition to phase transformations, the precipitation of carbides, grain growth, plastic deformation, discontinuous dynamic recrystallization (dDRX) of retained austenite grains, and continuous dynamic recrystallization (cDRX) of ferrite grains occurred during hot shear and subsequent cooling. The effects of the strain rate and forming temperature on the microstructural and textural evolution of niobium-microalloyed steel during hot shear and subsequent cooling were investigated and discussed. A niobium-microalloyed steel with a homogenous ultrafine-grained ferrite microstructure and intense γ-fiber texture was fabricated when the forming temperature, strain rate of hot shear deformation, and cooling rate of subsequent mist cooling were 1073 K, 20 s−1, and 10 K·s-1, respectively.