Lamellar Structure Research Articles

Mechanical properties of AlCoCrFeNi2.1 EHEA controlled via the coherent nano-precipitated phase during hot rolling

In the present work, the AlCoCrFeNi2.1 EHEA was hot rolled in multiple passes at different temperatures and reductions. The L12/B2 lamellar eutectic structure of the as-cast alloy disappeared after hot rolling and evolved into an irregular distribution of FCC and B2 phases resembling a heterogeneous structure. Combined with SEM and TEM microscopic characterization, it is evident that the nanoprecipitates in both the FCC and B2 phases simultaneously maintain a highly coherent relationship with their matrix structure, with the ordered L12 nanoprecipitates in FCC phase rich in Al and Ni, and the disordered BCC nanoprecipitates in B2 phase rich in Cr. The strength of the alloy can be greatly improved through microstructure evolution which can be directly derived from the back stress effect in the heterogeneous structure. The tensile fracture morphology and fracture mechanism were analyzed to further study this effect. More importantly, this work examined the effects of changes in the mean-free path of the dislocation induced by the morphology evolution and density of the nanoprecipitates on the mechanical properties. As a result, the microstructure and mechanical properties of hot rolled AlCoCrFeNi2.1 EHEA can be controlled to a certain extent.

Assessment of marine and urban-industrial environmental impact on stone acting as the base of a quaternary bronze sculpture

This work investigates the influence of a marine and urban-industrial environment on the deterioration of a funerary memorial in Getxo (Basque Country, Spain). The sculpture and artificial stone materials as well as their degradation products were characterised via a multi-analytical approach. An in situ characterisation of the bronze statue and its artificial limestone base was carried out with portable Energy Dispersive X-Ray Fluorescence (ED-XRF) and Raman spectrometers. In addition, several samples of white crusts as well as metal runoff crusts and biological patina were collected and some of them were prepared as cross-sections. High Resolution Micro-X-ray fluorescence and micro-Raman spectroscopy were used as non-destructive methods to detect original and degradation compounds. The test of soluble salts was also carried out on the samples and ion chromatography was employed in the laboratory. Exclusively calcite salt-efflorescences were found at the monument side with ED-XRF and Raman spectroscopy. While their morphology was compact at unsheltered sites, they showed a lamellar structure at sheltered locations, whose increased volume strongly influences the destruction of the memorial. The spectroscopic characterization of metal runoff showed that its excessive occurrence on the memorial surface was due to the dissolution of the copper-alloy caused by chemical reactivity with the surrounding acidic atmosphere. The formation of brochantite Cu4(SO4)(OH)6, posnjakite Cu4(SO4)(OH)6·(H2O), langite Cu4(SO4)(OH)6·2(H2O), or malachite Cu2(CO3)(OH)2 was favored exclusively in metal runoff crusts at unsheltered locations. However, much thinner crusts collected at sheltered sites showed a different composition, with copper species such as moolooite (Cu(C2O4)·nH2O) and atacamite Cu2Cl(OH)3. The soluble salt extraction showed a variable concentration of soluble ions depending on the area where the samples come from. The sample from north west sheltered location showed the highest content of sulfate, nitrate and chloride compounds. In addition, the concentration of fluoride and nitrate reflects the impact of contamination of surrounding industries.

Effect of peak stress and dwell time on the fatigue damage behavior of Ti-22Al-23Nb-2(Mo, Zr) alloy with lamellar microstructure

Ti2AlNb alloy is one of the candidate high strength titanium alloy materials under consideration for compressor disc, which will endure dwell loading at high peak stress level during service. In this work, low cycle fatigue (LCF) and low cycle dwell fatigue (LCDF) deformation behaviors and damage mechanism of Ti2AlNb alloy with lamellar microstructure under high loading level were investigated. The results show that fatigue life is highly dependent on the peak stress (σpeak) and dwell time (tdwell). With increasing the σpeak, the LCF life decreases gradually since higher loading stress can accelerate plastic strain accumulation and lead to faster crack propagation. When at the same σpeak, the LCDF life is lower than the LCF life due to greater plastic strain accumulation caused by dwell effect, indicating a dwell life debit of the Ti2AlNb alloy. Moreover, dwell fatigue sensitivity exhibits an increasing trend as the tdwell increases. Under different loading waveforms, the fractography shows remarkably different features. Crack source of LCF appears on sample surface, while crack source of LCDF appears on surface and sub-surface of sample. The research of LCDF behavior is relevant to aviation industry to prevent premature failure of rotating components made of Ti2AlNb alloys.

Effects of recrystallization on interfacial microstructure evolution and shear strength of TiAl alloy joints

The effects of dynamic recrystallization (DRX) and post-bonding heat treatment (PBHT) on the interfacial microstructure evolution and mechanical properties enhancement of Ti-43Al-4Nb-1Mo-0.2B alloy joints, subjected to various bonding parameters, were thoroughly investigated through detailed microstructural characterization and shear performance tests. A strip-like DRX area was observed at the interface when bonding at 1100 °C, ≥30 MPa, for 60 min. Equiaxial- γ grains underwent discontinuous dynamic recrystallization during the bonding process, and tended to form flat grains parallel to the lamellae direction during recrystallization annealing (1000 °C/6 h) owing to the hindrance imposed by the lamellae on both sides. The orientations of lamellae on the both sides of bonding interface affects the lamellae's stress distribution and deformation behavior at the bonding interface, subsequently influencing the DRX behavior and the width of the DRX zone. Static recrystallization (SRX) during the recrystallization annealing treatment can eliminate bonding defects of joints bonding at lower pressures or temperatures. Optimal joints with fully lamellar interfacial microstructure and excellent shear properties can be obtained through single-α phase annealing treatment. Lamellae microstructure tailored through PBHT can significantly enhance the quality of joints, attributed to the homogeneity of the microstructure between the interface and matrix. The highest shear strength of 478 MPa, accounting for 82 % of the matrix strength, was obtained under the bonding parameters of 1100 °C/30 MPa/60 min-1290 °C/15 min. This work provides important DB process parameters for fabricating of complex structural parts of TiAl alloy.

Spontaneous symmetry breaking in polar fluids

Spontaneous symmetry breaking and emergent polar order are each of fundamental importance to a range of scientific disciplines, as well as generating rich phase behaviour in liquid crystals (LCs). Here, we show the union of these phenomena to lead to two previously undiscovered polar liquid states of matter. Both phases have a lamellar structure with an inherent polar ordering of their constituent molecules. The first of these phases is characterised by polar order and a local tilted structure; the tilt direction processes about a helix orthogonal to the layer normal, the period of which is such that we observe selective reflection of light. The second new phase type is anti-ferroelectric, with the constituent molecules aligning orthogonally to the layer normal. This has led us to term the phases the SmCPH\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{{{{\\rm{Sm}}}}}}{{{{{{\\rm{C}}}}}}}_{{{{{{\\rm{P}}}}}}}^{{{{{{\\rm{H}}}}}}}$$\\end{document} and SmAAF phases, respectively. Further to this, we obtain room temperature ferroelectric nematic (NF) and SmCPH\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{{{{\\rm{Sm}}}}}}{{{{{{\\rm{C}}}}}}}_{{{{{{\\rm{P}}}}}}}^{{{{{{\\rm{H}}}}}}}$$\\end{document} phases via binary mixture formulation of the novel materials described here with a standard NF compound (DIO), with the resultant materials having melting points (and/or glass transitions) which are significantly below ambient temperature. The new soft matter phase types discovered herein can be considered as electrical analogues of topological structures of magnetic spins in hard matter.

General toxicity and screening of reproductive and developmental toxicity following bioaccumulation of oral-dosed perfluorooctanoic acid: Loss of the Golgi apparatus

Despite its widespread use as a stabilizer across various industries over the past several decades, the health effects of chronic exposure to PFOA are still unclear. We administered PFOA by oral gavage (0, 12.5, 50, and 200 μg/day/mouse, eight groups) to male and female mice for six months. Body weight gain decreased with dose accompanied by increased liver weight, and PFOA altered liver damage-related-blood biochemical indicators and induced pathological lesions, including hepatocellular hypertrophy, cholangiofibrosis, and centrilobular hepatocellular vacuolation. Loss of the Golgi apparatus, formation of lamellar body-like structures, and lipid accumulation were observed in the liver of PFOA-treated mice. We also cohabited five pairs of male and female mice for the last ten days of administration, dosed PFOA to dam up to 28 days after birth, and investigated effects on reproduction and development. The survival rate of pups and the sex ratio of surviving mice decreased significantly at the highest dose. PFOA tissue concentration increased with the dose in the parent mice's liver and the pups' blood and brain. Taken together, we suggest that PFOA primarily affects the liver and reproduction system and that disturbance in lipid metabolism and Golgi's structural stability may be involved in PFOA-induced toxicity.

Evolution of elliptical SAXS patterns in aligned systems.

Small-angle X-ray and neutron scattering (SAXS and SANS) patterns from certain semicrystalline polymers and liquid crystals contain discrete reflections from ordered assemblies and central diffuse scattering (CDS) from uncorrelated structures. Systems with imperfectly ordered lamellar structures aligned by stretching or by a magnetic field produce four distinct SAXS patterns: two-point 'banana', four-point pattern, four-point 'eyebrow' and four-point 'butterfly'. The peak intensities of the reflections lie not on a layer line, or the arc of a circle, but on an elliptical trajectory. Modeling shows that randomly placed lamellar stacks modified by chain slip and stack rotation or interlamellar shear can create these forms. On deformation, the isotropic CDS becomes an equatorial streak with an oval, diamond or two-bladed propeller shape, which can be analyzed by separation into isotropic and oriented components. The streak has elliptical intensity contours, a natural consequence of the imperfect alignment of the elongated scattering objects. Both equatorial streaks and two- and four-point reflections can be fitted in elliptical coordinates with relatively few parameters. Equatorial streaks can be analyzed to obtain the size and orientation of voids, fibrils or surfaces. Analyses of the lamellar reflection yield lamellar spacing, stack orientation (interlamellar shear) angle α and chain slip angle ϕ, as well as the size distribution of the lamellar stacks. Currently available computational tools allow these microstructural parameters to be rapidly refined.

Getting Nosy: Olfactory Rosette Morphology and Lamellar Microstructure of Two Chondrichthyan Species.

To smell, fish rely on passive water flow into their olfactory chambers and through their olfactory rosettes to detect chemical signals in their aquatic environment. The olfactory rosette is made up of secondarily folded tissues called olfactory lamellae. The olfactory morphology of cartilaginous fishes varies widely in both rosette gross morphology and lamellar microstructure. Previous research has shown differences in lamellar sensory morphology depending on the position along the rosette in hammerheads (family Sphyrnidae). Here, we investigate if this pattern continues in members of two other chondrichthyan families: Squalidae and Chimaeridae. Using contrast-enhanced microCT and scanning electron microscopy, we investigated patterns in lamellar morphology based on lamellar position along the olfactory rosette in Pacific spiny dogfish (Squalus suckleyi) and spotted ratfish (Hydrolagus colliei). We describe the gross olfactory rosette anatomy and lamellar microstructure of both species. We also put forth a new method, combining 3D morphological microCT data with 2D SEM microstructure data to better approximate lamellar sensory surface area. We found that in both species, lamellae in the center of the rosette were larger with more secondary folds. However, we found no significant differences in lamellar sensory surface area among lamellar positions. Previously, differences in lamellar sensory morphology have been tied to the internal fluid dynamics of the olfactory chamber. It is possible that the internal flow dynamics of these species are like other chondrichthyan models, where water flow patterns differ in the lateral vs the medial part of the organ, and the consistent distribution of sensory tissue does not correspond to this flow. Alternatively, the olfactory morphology of these species may result in uniform flow patterns throughout the olfactory chamber, correlating with the consistent distribution of sensory tissue throughout the organ. This study emphasizes that further investigations into chondrichthyan fluid dynamics is paramount to any future studies on the correlations between distribution of sensory tissues and water flow.

Enhancing coercivity and thermal stability of (Nd,Y)–Fe–B sintered magnets through lamellar structure design

Enhancing coercivity and thermal stability of (Nd,Y)–Fe–B sintered magnets through lamellar structure design

Preparation and Effect of CO2 Response Gel for Plugging Low-Permeability Reservoirs.

In order to solve the problem of gas channeling during CO2 flooding in low-permeability reservoirs, a novel CO2 responsive gel channeling system was prepared by using carrageenan, branched polyethylene imide and ethylenediamine under laboratory conditions. Based on the Box-Behnken response surface design method, the optimal synthesis concentration of the system was 0.5 wt% carrageenan, 2.5 wt% branchized polyethylenimide and 6.5 wt% ethylenediamine. The micromorphology of the system before and after response was characterized by scanning electron microscopy. The rheology and dehydration rate were tested under different conditions. The channeling performance and enhanced oil recovery effect of the gel system were simulated by a core displacement experiment. The experimental results show that the internal structure of the system changes from a disordered, smooth and loosely separated lamellae structure to a more uniform, complete and orderly three-dimensional network structure after exposure to CO2. The viscosity of the system was similar to aqueous solution before contact with CO2 and showed viscoelastic solid properties after contact with CO2. The experiment employing dehydration rates at different temperatures showed that the internal structure of the gel would change at a high temperature, but the gel system had a certain self-healing ability. The results of the displacement experiment show that the plugging rate of the gel system is stable at 85.32% after CO2 contact, and the recovery rate is increased by 17.06%, which provides an important guide for the development of low-permeability reservoirs.

Dynamic Response of Ti-6Al-2Zr-1Mo-1V Alloy Manufactured by Laser Powder-Bed Fusion.

Titanium parts fabricated by additive manufacturing, i.e., laser or electron beam-powder bed fusion (L- or EB-PBF), usually exhibit columnar grain structures along the build direction, resulting in both microstructural and mechanical anisotropy. Post-heat treatments are usually used to reduce or eliminate such anisotropy. In this work, Ti-6Al-2Zr-1Mo-1V (TA15) alloy samples were fabricated by L-PBF to investigate the effect of post-heat treatment and load direction on the dynamic response of the samples. Post-heat treatments included single-step annealing at 800 °C (HT) and a hot isotropic press (HIP). The as-built and heat-treated samples were dynamically compressed using a split Hopkinson pressure bar at a strain rate of 3000 s-1 along the horizontal and vertical directions paralleled to the load direction. The microstructural observation revealed that the as-built TA15 sample exhibited columnar grains with fine martensite inside. The HT sample exhibited a fine lamellar structure, whereas the HIP sample exhibited a coarse lamellar structure. The dynamic compression results showed that post-heat treatment at 800 °C led to reduced flow stress but enhanced uniform plastic strain and damage absorption work. However, the HIP samples exhibited both higher stress, uniform plastic strain, and damage absorption work owing to the microstructure coarsening. Additionally, the load direction had a subtle influence on the flow stress, indicating the negligible anisotropy of flow stress in the samples. However, there was more significant anisotropy of the uniform plastic strain and damage absorption. The samples had a higher load-bearing capacity when dynamically compressed perpendicular to the build direction.

Heterogeneous‐Structured Refractory High‐Entropy Alloys: A Review of State‐of‐the‐Art Developments and Trends

AbstractRefractory high‐entropy alloys (RHEAs) inspire the development of novel high‐temperature structural materials due to their outstanding resistance to softening and phase stability at elevated temperatures. However, they struggle to simultaneously achieve high‐temperature strength and room‐temperature ductility, while exhibiting insufficient room‐temperature strain hardening capability. Heterogeneous structure strengthening possesses a unique plastic self‐coordinated ability, which can effectively maintain strain hardening rate to achieve an excellent combination of strength and ductility. Benefiting from slow atomic diffusion, severe lattice distortion, and broad compositional design space, RHEAs with heterogeneous structures can be prepared from both chemical composition and interface structure perspectives. Chemical composition heterogeneity primarily focuses on fluctuations of alloying elements at the nanoscale, along with the formation of heterogeneous precipitates and unique lamellar eutectic structures. While, interface structure heterogeneity manifests in the activation of phase transformation and twin boundaries within grains, along with the formation of grains of vastly different sizes. The trend in RHEAs development is toward structural‐functional integration. Heterogeneous structures can also optimize functional properties, such as irradiation resistance, biomedical properties, and high‐temperature softening resistance of RHEAs. Finally, a brief outlook is provided on the future development direction of heterogeneous structure RHEAs.

Lightweight, Elastic, and Superhydrophobic Multifunctional Organic-Inorganic Fibrous Aerogels for Efficient Oily Wastewater Purification and Electromagnetic Microwave Absorption.

Lightweight and robust aerogels with multifunctionality are highly desirable to meet the technological demands of current society. Herein, we designed lightweight, elastic, and superhydrophobic multifunctional organic-inorganic fibrous hybrid aerogels which were assembled with organic aramid nanofibers and inorganic hierarchical porous carbon fibers. Thanks to the organic-inorganic fiber hybridization strategy, the optimal aerogels possessed remarkable compressibility and elasticity. Benefiting from the microscopic hierarchical porous structure of carbon fibers and the macroscopic macroporous lamellar structure of aerogels, the optimal aerogels exhibited superb lightweight property, conspicuous electromagnetic microwave absorption ability, and outstanding oily wastewater purification capacity. As for electromagnetic microwave absorption, it achieved a strong reflection loss of -41.8 dB, and the effective absorption bandwidth reached 6.86 GHz. Besides, the oil adsorption capacity for trichloromethane reached as high as 93.167 g g-1 with a capacity retention of 95.6% after 5 cycles. Meanwhile, it could act as a gravity-driven separation membrane to continuously separate trichloromethane from a trichloromethane-water mixture with a high flux of 7867.37 L·m-2·h-1, even for surfactant-stabilized water-in-n-heptane emulsions of 3794.94 L·m-2·h-1. Such a strategy might shed some light on the construction of multifunctional aerogels toward broader applications.

Effect of Heterogeneous Deformation on Microstructure and Microtexture Evolution of Ti‐6Al‐4V Alloy during Multidirectional Isothermal Forging

The heterogeneous deformation of Ti‐6Al‐4V alloy during multidirectional isothermal forging and its effect on microstructure, microtexture, and related mechanical properties are investigated here. It is found that lowering the deformation temperature, combined with increasing the number of forging times, accelerates the grain refinement and recrystallization process in the as‐received billet, especially in the surface section rather than the inner of the billet. Finally, a heterogeneous lamellar structure is formed after annealing the billet with a fourth step of forging. The heterogeneous lamella structure enables a better synergy of strength and ductility when compared to its equiaxed counterpart, achieving a high tensile strength of 1194 MPa and an elongation of 13.1%. During the deformation, a high proportion of back stress to total flow stress, ranging from 64–67%, denotes that back stress strengthening is one of the main reasons for the better synergy of strength and ductility. This study guides a low‐cost and convenient way for the regulation of microstructure and mechanical properties of titanium alloy with good performance.

Supramolecular structure and physiochemical properties of annealed maize starches: Effect of starch granule-associated surface and channel proteins

To investigate the effect of starch granule-associated surface and channel proteins (GSCP) on starch during annealing, normal maize starch (NMS) and waxy maize starch (WMS) were subjected to protease treatment then annealing for 0–36 h to study changes in structural and physicochemical properties. The removal of GSCP accelerated the rate of increase in granule size of NMS during annealing. XRD results showed that annealing initially decreases the crystalline order of starch granules, but with prolonged annealing, the relative crystallinity increases. Also, GSCP removal decreases the rate of reduction in relative crystallinity during annealing. The lamellar structure of starch becomes compact in the initial state of annealing. With extended annealing time, the rearrangement of the microcrystalline structure may result in a decrease in compactness. The dual treatment increased the thickness of crystalline lamellae (dc), and the removal of GSCP advanced the change of lamellar structure during annealing. From pasting results, the rigidity of swollen starch was reduced after GSCP removal, while it increased with annealing time for NMS. This study adopted a GSCP removal method that had minimal impact on the structure of starch granules, providing novel information about the role of GSCP in the annealing of maize starch.

Machinability of Ti6Al4V Alloy: Tackling Challenges in Milling Operations

This study extensively elaborates the approach towards making ease in 3D milling of Titanium Alloy Grade 5; by adapting the controlled parameters and specific strategies in cutting tool encroachment in milling. Every manufacturer is anxious about the machinability index (20%) of Ti6Al4V, which affects the machining efficiency proportionally. During machining, Phase alteration above the 8820C produces a Beta lamellar equiaxed microstructure, which is hard; also, limited thermal conductivity allows the generated heat towards the cutting tool to lead the Thermo-assisted wear. Higher temperatures also initiated chemically eagerness of Ti6Al4V and reacted with cutting tool edge and escorts towards catastrophic failure. The difficult Machinability demonstrates the detrimental notable effect on the cutting tool's health and follows the Ti6Al4V surface quality. The Cooling methods can flush out chips and frictional heat with ample lubrication, desirably controlling the worse effect of Machinability to some extent blissfully. The cutting tool material and coating, has chemically inert and excellent thermal conductivity with an aggressive rake angle with higher relief angle, improves the shearing tendency of Ti6Al4V by avoiding smearing, ultimately speculated surface quality with desired Tool life through higher Machining efficiency in milling.

Lamellar structure of high-strength direct-spun CNT yarns: Implications for interface failure

A previously unreported nanoscale lamella structure in a direct spun high strength carbon nanotube (CNT) yarn was identified and characterized. The thickness of the lamellae is in the order of 100 nm. The lamella structure is present in the entire cross-section. It is hypothesized that the lamella structure originates from a single thin sheet (felt) during the manufacturing process, between steps of CNT aerogel and CNT roving. The existence of this lamella structure has direct implications on the yarn-resin interface behavior of derived composites and, subsequently, the mechanical performance of CNT yarn composites. Peridynamic simulations of four distinct yarn pullout experiments captured the observed failure behavior influenced by microstructure.

The formation of lamellar body-like structures may be a trigger of cetylpyridinium chloride-induced cell death and inflammatory response

Cetylpyridinium chloride (CPC) is a quaternary ammonium compound used widely in health and personal care products. Meanwhile, due to its increasing use, its potential adverse health effects are emerging as a topic of public concern. In this study, we first administered CPC by pharyngeal aspiration to determine the survival level (the maximum concentration at which no death is observed) and then administered CPC to mice repeatedly for 28 days using the survival level as the highest concentration. CPC increased the total number of pulmonary cells secreting pro- and anti-inflammatory cytokines and chemokines. Infiltration of inflammatory cells, production of foamy alveolar macrophages, and chronic inflammatory lesions were found in the lung tissue of male and female mice exposed to the highest dose of CPC. We also investigated the toxicity mechanism using BEAS-2B cells isolated from normal human bronchial epithelium. At 6 h after exposure to CPC, the cells underwent non-apoptotic cell death, especially at concentrations greater than 2 μg/mL. The expression of the transferrin receptor was remarkably enhanced, and the expression of proteins that contribute to intracellular iron storage was inhibited. The expression of both mitochondrial SOD and catalase increased with CPC concentration, and PARP protein was cleaved, suggesting possible DNA damage. In addition, the internal structure of mitochondria was disrupted, and fusion between damaged organelles was observed in the cytoplasm. Most importantly, lamellar body-like structures and autophagosome-like vacuoles were found in CPC-treated cells, with enhanced expression of ABCA3 protein, a marker for lamellar body, and a docking score between ABCA3 protein and CPC was considered to be approximately −6.8969 kcal/mol. From these results, we propose that mitochondrial damage and iron depletion may contribute to CPC-induced non-apoptotic cell death and that pulmonary accumulation of cell debris may be closely associated with the inflammatory response. Furthermore, we hypothesize that the formation of lamellar body-like structures may be a trigger for CPC-induced cell death.

Combination of a Topical Anti-Inflammatory Drug and a Moisturizer, Both with a Lamellar Structure Containing Synthetic Pseudo-Ceramides, for the Treatment of Patients with Mild-to-Moderate Atopic Dermatitis.

Atopic dermatitis is characterized by chronic inflammation and dryness accompanied by severe itching. The combined use of moisturizers and topical anti-inflammatory drugs is essential for alleviating atopic dermatitis. We have developed a topical anti-inflammatory drug with a steroid and a moisturizer with heparinoid, both in lamellar structure-based formulations containing synthetic pseudo-ceramides. Here, assessed the efficacy of this combination in the treatment of atopic dermatitis. We included 22 patients with mild to moderate atopic dermatitis and subjected them to a seven-week treatment with the test formulations, followed by a four-week post-treatment period. Clinical findings and the quality of life of participants remarkably improved after one week of treatment. Furthermore, skin hydration and transepidermal water loss considerably improved at weeks one and three, respectively. The Cer [NP]/[NS] ratio, an indicator of epidermal turnover, substantially increased during the treatment period and remained elevated even thereafter. The improvement in stratum corneum function was distinctive in participants with lower barrier function. These findings indicated that the combined use of the anti-inflammatory drug and moisturizer, both in lamellar structure-based formulations, is effective in treating atopic dermatitis in patients with fragile barrier function.

In vivo evaluation of bioactivity of alginate/chitosan based osteoplastic nanocomposites loaded with inorganic nanoparticles

The influence of two nanostructured osteoplastic materials with different compositions: i) alginate (Alg) matrix, loaded with Zn2+ ions and nanostructured hydroxyapatite (HA) - S1/HA-Zn, and ii) chitosan (CS) matrix loaded with brushite nanoparticles (NPs, dicalcium phosphate dihydrate, DCPD) - S2/DCPD on the healing of an experimental femoral diaphysis defect was investigated. The structure of cellular elements and the lacunar tubular system of the regenerated bone tissue were studied by electron microscopy. Osteogenic cells on the surface and inside S1/HA-Zn formed bone tissue. On the 30th day, the latter had a reticulofibrous and later lamellar structure. On the 30th day, the S2/DCPD biomaterial was integrated mainly into connective tissue and, starting from the 90th day, into the bone tissue, which was formed only on its outer surface. Thus, it has been proven that both biomaterials contribute to the healing of bone wounds. The regenerative potential of the new bone tissue formation of S1/HA-Zn prevails over that of S2/DCPD.