Search Results (1,315)

Background/Objectives: The melt-spinning process has seen limited application in the pharmaceutical industry. However, nano- and microfibrous structures show significant potential for novel drug delivery systems, due to their high specific surface area. To facilitate broader adoption in pharmaceutical technology, critical parameters influencing fiber quality and yield must be investigated. In this study, we aimed to develop an isomalt-based microfibrous carrier system for active pharmaceutical ingredients. Methods: The effects of different isomalt compositions—specifically, varying ratios of GPS (6-O-α-d-glucopyranosyl-d-sorbitol) and GPM (1-O-α-d-glucopyranosyl-d-mannitol)—as well as key process parameters, were systematically investigated to optimize fiber formation. The prepared fibers underwent different treatments. Morphological changes were monitored with a microscope, and microstructural changes were studied using a differential scanning calorimeter and X-ray diffractometer. The macroscopic behavior of the fibers was evaluated by image analysis under monitored conditions. Results: Statistical analysis was used to determine the optimal setting to produce isomalt-based fibers. We found that storage over ethanol vapor has a positive effect on the stability of the fibers. We successfully prepared ibuprofen sodium-containing fibers that remained stable after alcohol treatment and enabled drug release within 15 s. Conclusions: It was found that the applied GPS:GPM isomalt ratio significantly influenced fiber formation and that storage over ethanol positively influenced the processability and stability of the fibrous structure. An isomalt-based microfibrous system with advantageous physicochemical and structural properties was successfully developed as a potential drug carrier. The system is also resistant to the destructive effects of ambient humidity, enabling preparation of suitable dosage forms. Full article

Biomaterials modified by antibacterial substances, including nanoparticles, open new opportunities for the effective treatment of infected wounds. Unfortunately, most publications focused only on experiments in vitro, with limited understanding of their potential for the clinic. This study evaluates the effectiveness in vivo of electrospun chitosan/polylactic acid (Ch/PLA) membranes enriched with silver nanoparticles (AgNPs) for purulent wound treatment. The composite biomaterial integrates chitosan’s biocompatibility and antimicrobial activity with PLA’s structural integrity, while AgNPs enhance antibacterial efficacy against major wound pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia aureus. A full-thickness purulent wound model was established in a rat model, and the animals were divided into three treatment groups: (i) Ch/PLA, (ii) Ch/PLA-AgNPs, and (iii) PLA-chlorhexidine (control). Wound healing was monitored over 21 days through macroscopic evaluation, histology, immunohistochemistry, and microbiological analysis. The Ch/PLA-AgNPs membranes significantly reduced bacterial colonization within 4–6 days, promoted granulation tissue formation, and accelerated epithelialization compared to the non-modified Ch/PLA scaffold. By day 15, complete wound closure was observed in the Ch/PLA-AgNPs group, comparable to PLA-chlorhexidine-treated wounds. Immunohistochemical analysis revealed a controlled inflammatory response with a balanced macrophage M1/M2 transition, supporting efficient tissue regeneration. Furthermore, systemic toxicity assessments indicated no significant adverse effects on internal organs. These findings demonstrate that electrospun Ch/PLA-AgNPs membranes effectively accelerate purulent wound healing by combining antimicrobial protection with biocompatible tissue support. This innovative approach presents a promising alternative to conventional wound dressings and paves the way for clinical applications in managing infected wounds. Full article

The plastic deformation during equal-channel angular pressing (ECAP) can be affected by various material- and processing-related factors. For instance, the initial crystal orientation and grain size play an important role in determining the material flow, which may cause localized deformation in terms of macroscopic deformation banding. In this study, we use a continuous cast AA1080 aluminum alloy with coarse columnar grains to analyze the influence of casting texture on the local material flow during ECAP. Billets are extracted with their columnar grains inclined either in the same direction as the ECAP shear plane or opposite to it. Visio-plastic analysis is performed on split billets. The pass is interrupted halfway through the ECAP tool to accurately capture steady-state deformation conditions. Flow lines at several positions within the billet are identified based on the positions of deformed and undeformed marker points and fitted to a phenomenological model based on a super-ellipse function. For further characterization, hardness measurements, optical and electron microscopy are carried out on the ECAP-deformed samples. Significant differences in terms of local material flow and microstructure evolution regarding the resulting crystal orientation and deformation banding are observed. Our results confirm and emphasize the importance of initial grain size and texture effects for ECAP processing. Full article

Background/Objectives: Brown tumors are bone manifestations of hyperparathyroidism, and they are characterized by histologic similarities with Central Giant Cell Granuloma (CGCG). Their diagnosis requires clinical, microscopic, macroscopic, and serologic correlation, as there is usually an elevation in parathormone levels due to the underlying metabolic disorder. Methods: This case describes a patient with a left mandibular lesion and a history of CGCG. Results: Through the joint analysis of clinical, histologic, and serologic findings, the diagnosis of a brown tumor associated with hyperparathyroidism was confirmed. Conclusions: This case highlights the importance of a comprehensive evaluation of oral and systemic features for accurate diagnoses and appropriate patient management. Full article

Coal is still China’s primary energy source, and the production process of coal produces industrial byproduct coal gangue. This study explores the possibility of using industrial byproducts of thermal power generation, fly ash (FA) and calcined coal gangue (CCG), as a partial (10% and 20%) substitute for cement in construction materials. Methodical research was conducted to determine how these two substances affect the microstructure and macroscopic characteristics of cement-based materials. Macroscopic performance test findings indicate that replacing 20% of cement with CCG had no discernible effect on the specimens’ performance. At the same time, adding FA required 28 days to be comparable to the control group. Mercury intrusion porosimetry (MIP) test results show that using CCG can refine microscopic pores. Additional hydration products could be produced by these materials, according to analyses using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The production of hydration products by CCG to fill the microscopic pores was further demonstrated by scanning electron microscopy (SEM) pictures. After 28 days of hydration, a layer of hydration products developed on the surface of FA. When supplementary cementitious materials (SCMs) were added, calcium hydroxide (CH) was consumed by interacting with FA and CCG to form additional hydration products, according to thermogravimetric analysis (TG) data after 28 days. Furthermore, an evaluation of FA and CCG’s effects on the environment revealed that their use performed well in terms of sustainable development. Full article

The depositional environment of the Permian Longtan shale (LS) in southwestern Guizhou Province, China, has been analyzed using mineralogical and geochemical approaches. Macroscopic observations of those studied LS samples showed that the LS is rather homogeneous and interbedded with coal strips, suggesting a relatively stable and shallow water environment. A detailed microscopic analysis demonstrated that higher land plants contributed the predominant proportion of organic matter in the LS. Inorganic geochemical analysis revealed a mixed source of materials with relatively larger proportions of basalt and andesite. Semiarid to humid and warm climates corresponding to an overall intensive weathering were deduced in the late Permian periods. The LS was deposited in a brackish-to-marine water environment with an oxic to dysoxic redox condition. Sea level rise/down coupled with changes in climate, water salinity, and redox condition jointly controlled the formation of the Longtan shale. Mineralogical composition indicates that the LS mainly comprises of argillaceous with minor siliceous facies, which will likely bring challenges for hydraulic fracturing. Full article

As a discontinuous deformation method, the block element method (BEM) characterizes a material’s elastoplastic behavior through the constitutive relation of thin-layer elements between adjacent blocks. To realistically simulate rock damage paths, this work improves the traditional BEM by using random Voronoi polygonal grids for discrete modeling. This approach mitigates the distortion of damage paths caused by regular grids through the randomness of the Voronoi grids. As the innovation of this work, the iterative algorithm is combined with polygonal geometric features so that the area–perimeter fractal dimension can be introduced to optimize random Voronoi grids. The iterative control index can effectively improve the geometric characteristics of the grid while maintaining the necessary randomness. On this basis, a constitutive relation model that considers both normal and tangential damage is proposed. The entire process from damage initiation to macroscopic fracture failure in rocks is described using two independent damage surfaces and a damage relationship based on geometric mapping relationships. The analysis results are in good agreement with existing experimental data. Furthermore, the sensitivity method is used to analyze the influence of key mechanical parameters in the constitutive model. Full article

This study aims to clarify the nonlinear pressure loss patterns of the pneumatic system in a pneumatic seeder under varying pipeline structures and airflow parameters, and to develop a rapid prediction equation for the main pipe’s pressure loss. The studied multi-branch pipeline system consists of a main pipe, a header, and ten branch pipes. The main pipe is vertically installed at the center of the header in a straight-line configuration. The ten branch pipes are symmetrically and evenly spaced along the axial direction of the header, distributed on both sides of the main pipe. The outlet directions of the branch pipes are arranged in a 180° orientation opposite to the inlet direction of the main pipe, forming a symmetric multi-branch configuration. Firstly, this study investigated the flow characteristics within the multi-branch pipeline of the pneumatic system and elaborated on the mechanism of flow division in the pipeline. The key geometric factors affecting airflow were identified. Secondly, from a microscopic perspective, CFD simulations were employed to analyze the fundamental causes of pressure loss in the multi-branch pipeline system. Finally, from a macroscopic perspective, a dimensional analysis method was used to establish an empirical equation describing the relationship between the pressure loss (P) and several influencing factors, including the air density (ρ), air’s dynamic viscosity (μ), closed-end length of the header (Δl), branch pipe 1’s flow rate (Q), main pipe’s inner diameter (D), header’s inner diameter (γ), branch pipe’s inner diameter (d), and the spacing of the branch pipe (δ). The results of the bench tests indicate that when 0.0018 m³·s⁻¹ ≤ Q ≤ 0.0045 m³·s⁻¹, 0.0272 m < d ≤ 0.036 m, 0.225 m < δ ≤ 0.26 m, 0.057 m ≤ γ ≤ 0.0814 m, and 0.0426 m ≤ D ≤ 0.0536 m, the prediction accuracy of the empirical equation can be controlled within 10%. Therefore, the equation provides a reference for the structural design and optimization of pneumatic seeders’ multi-branch pipelines. Full article

Papillomaviruses (PVs) are double-stranded DNA viruses known to induce a variety of epithelial lesions in dogs, ranging from benign hyperplasia to malignancies. In regions of rich biodiversity such as the Western Amazon, data on the circulation and genetic composition of canine papillomaviruses (CPVs) remain scarce. This study investigated CPV types present in oral and cutaneous papillomatous lesions in domiciled dogs from Acre and Rondônia States, Brazil. Sixty-one dogs with macroscopically consistent lesions were clinically evaluated, and tissue samples were collected for histopathological examination and PCR targeting the L1 gene. Among these, 37% were histologically diagnosed as squamous papillomas or fibropapillomas, and 49.2% (30/61) tested positive for papillomavirus DNA. Sequencing of the L1 gene revealed that most positive samples belonged to CPV1 (Lambdapapillomavirus 2), while one case was identified as CPV8 (Chipapillomavirus 3). Complete genomes of three CPV1 strains were obtained via high-throughput sequencing and showed high identity with CPV1 strains from other Brazilian regions. Phylogenetic analysis confirmed close genetic relationships among isolates across distinct geographic areas. These findings demonstrate the circulation of genetically conserved CPVs in the Amazon and reinforce the value of molecular and histopathological approaches for the accurate diagnosis and surveillance of viral diseases in domestic dogs, especially in ecologically complex regions. Full article

Spruce wood is a natural polymeric material, consisting of cellulose, lignin, hemicelluloses and other secondary components, which gives it a unique chemical footprint and architecture. Varnishes are used in musical instruments to protect the wood against humidity variations, wood being a hygroscopic material, but also to protect the wood from dirt. The varnishes used both to protect the wood from resonance and to ensure a special aesthetic appearance are either polymeric varnishes (nitrocellulose, oil-based) or volatile solvents (spirit). In this study, the color changes, the surface morphology and the chemical spectrum produced by three types of varnishes, applied in 5, 10 and 15 layers, on resonance spruce plates were analyzed. The results revealed significant changes in the color parameters: the lightness decreased by approximately 17% after the first layer, by 50% after 5 layers, by 65% after 10 layers and by 70% after 15 layers. The color parameters are most influenced by the anatomical quality of spruce wood (annual ring width and earlywood/latewood ratio) in the case of oil-based varnishes and least influenced in the case of nitrocellulose varnishes. The chemical fingerprint was determined by FTIR spectrum analysis, which revealed that the most pronounced absorptions were the double band 2926–2858 cm⁻¹, corresponding to aliphatic methylene and methyl groups (asymmetric and symmetrical C-H stretch), and the bands at 1724 cm⁻¹ (oil-based varnish), 1722 cm⁻¹ (nitrocellulose varnish) and 1708 cm⁻¹ (spirit varnish), all assigned to non-conjugated carbonyl groups in either carboxylic acids, esters aldehydes or ketones. The novelty of the study lies in the comparative analysis of three types of varnishes used in the musical instrument industry, applied to samples of spruce resonance wood with different macroscopic characteristics in three different layer thicknesses. Full article

The Junggar Basin contains a large amount of coal resources and is an important coal production base in China. The coal seam in Zhundong coalfield has a large single-layer thickness and high content of inertinite, but large particle Fe-sulphide minerals are associated with coal seams in some mining areas. A series of economic and environmental problems caused by the combustion of large-grained Fe-sulphide minerals in coal have seriously affected the economic, clean and efficient utilization of coal. In this paper, the ultra-thick coal seam of the Xishanyao formation in the Yihua open-pit mine of the Zhundong coalfield is taken as the research object. Through the analysis of coal quality, X-ray fluorescence spectrometer test of major elements in coal, inductively coupled plasma mass spectrometry test of trace elements, SEM-Raman identification of Fe-sulphide minerals in coal and LA-MC-ICP-MS test of sulfur isotope of marcasite, the coal quality characteristics, main and trace element characteristics, macro and micro occurrence characteristics of Fe-sulphide minerals and sulfur isotope characteristics of marcasite in the ultra-thick coal seam of the Xishanyao formation are tested. On this basis, the occurrence state and genesis of large particle Fe-sulphide minerals in the ultra-thick coal seam of the Xishanyao formation are clarified. The main results and understandings are as follows: (1) the occurrence state of Fe-sulphide minerals in extremely thick coal seams is clarified. The Fe-sulphide minerals in the extremely thick coal seam are mainly marcasite, and concentrated in the YH-2, YH-3, YH-8, YH-9, YH-14, YH-15 and YH-16 horizons. Macroscopically, Fe-sulphide minerals mainly occur in three forms: thin film Fe-sulphide minerals, nodular Fe-sulphide minerals, and disseminated Fe-sulphide minerals. Microscopically, they mainly occur in four forms: flake, block, spearhead, and crack filling. (2) The difference in sulfur isotope of marcasite was discussed, and the formation period of marcasite was preliminarily divided. The overall variation range of the δ³⁴S value of marcasite is wide, and the extreme values are quite different. The polyflake marcasite was formed in the early stage of diagenesis and the δ³⁴S value was negative, while the fissure filling marcasite was formed in the late stage of diagenesis and the δ³⁴S value was positive. (3) The coal quality characteristics of the thick coal seam were analyzed. The organic components in the thick coal seam are mainly inertinite, and the inorganic components are mainly clay minerals and marcasite. (4) The difference between the element content in the thick coal seam of the Zhundong coalfield and the average element content of Chinese coal was compared. The major element oxides in the thick coal seam are mainly CaO and MgO, followed by SiO₂, Al₂O₃, Fe₂O₃ and Na₂O. Li, Ga, Ba, U and Th are enriched in trace elements. (5) The coal-accumulating environment characteristics of the extremely thick coal seam are revealed. The whole thick coal seam is formed in an acidic oxidation environment, and the horizon with Fe-sulphide minerals is in an acidic reduction environment. The acidic reduction environment is conducive to the formation of marcasite and is not conducive to the formation of pyrite. (6) There are many matrix vitrinite, inertinite content, clay content, and terrigenous debris in the extremely thick coal seam. The good supply of peat swamp, suitable reduction environment and pH value, as well as groundwater leaching and infiltration, together cause the occurrence of large-grained Fe-sulphide minerals in the extremely thick coal seam of the Xishanyao formation in the Zhundong coalfield. Full article

The kinetics of liquid transport in textiles are determined by the thermodynamic boundary conditions and the substrate’s structure. The knitting process offers a wide range of possibilities for modifying the fabric structure, making it ideal for high-performance garments and technical applications. Given the highly complex nature of textiles’ interaction with liquids, this paper investigates how fabric structure affects combined wicking and drying behaviour. This facilitates comprehension of the underlying transport processes on the yarn and fabric scale, which is important for understanding the behaviour of the material as a whole. The presented experiment combines analysis of wicking through radial liquid spread using imaging techniques and analysis of the drying process through gravimetric measurement of evaporation. Eight samples of single jersey knitted fabrics were produced using polyester yarns of different texturization and fibre diameters on flat and circular knitting machines. The fabrics demonstrate significantly different wicking behaviours depending on their structure. The fabric’s drying time and rate are directly linked to the macroscopic spread of the liquid. Large inter-yarn pores hinder liquid spread. For the lowest liquid saturations, the yarn structure plays a critical role. Using fine, dense yarns can hinder convective drying within the yarn. Textured yarns tend to exhibit higher specific drying rates. The results offer a comprehensive insight into the interplay between the fabric’s structure and its wicking and drying behaviour, which is crucial for the development of functional fabrics in the knitting process. Full article

High-energy solid propellants are multiphase engineering materials, whose mechanical behavior is predominantly governed by the characteristics of embedded crystalline particles. While microstructural influences have been extensively examined, quantitative correlations between microstructure and macroscopic mechanical properties remain underexplored. This work develops a cohesive finite element method (CFEM) framework to quantify the thermomechanical response of high-energy solid propellants at the microstructural scale. The analysis focuses on impact loading at strain rates ranging from 10³ to 10⁴ s⁻¹, accounting for large deformation, thermomechanical coupling, and microcrack-induced failure. Damage evolution under impact conditions was evaluated using a combined neural network-based inverse identification method and a three-dimensional cohesive finite element model to determine temperature-dependent bilinear-polynomial cohesive parameters. Results demonstrate a strong dependence of the propellant’s mechanical behavior on both strain rate and temperature. Validation against experimental data confirms that the proposed temperature-sensitive CFEM accurately predicts both damage progression and macroscopic mechanical responses. Full article

Oregano (Origanum vulgare) cultivation is of great economic importance in Peru. Tacna stands out as its main producer. However, the presence of phytopathogenic fungi represents a challenge for its production. This study aimed to characterize both the morphological and molecular levels of the causal agent of crown and root rot in a crop field in the Camilaca district, Candarave, Tacna. To this end, systematic sampling was carried out using the five-gold method, collecting plants with typical symptoms. Fungi were isolated from diseased roots and characterized using macroscopic and microscopic morphological analysis as well as sequencing and multilocus phylogenetic analysis (ITS, 28S, HIS3, TEF1, TUB2). In addition, pathogenicity tests were performed on healthy plants to confirm the infectivity of the isolates. The results demonstrated that root rot was caused by a complex of phytopathogenic fungi through phylogenetic analysis of Dactylonectria torresensis, Fusarium oxysporum, F. iranicum, and F. redolens. These findings represent the first report of these species as causal agents of oregano root rot in Peru, highlighting the need for integrated management strategies that reduce the economic impact of these diseases and contribute to the sustainability of the crop in key producing regions such as Tacna. Full article

Shoulder-assisted heating friction plug welding (SAH-FPW) experiments were conducted to repair keyhole-like volumetric defects in 6082-T6 aluminum alloy, employing a novel concave backing hole technique on a flat backing plate. This approach yielded well-formed plug welded joints without significant macroscopic defects. Notably, the joints exhibited no thinning on the top surface while forming a reinforcing boss structure within the concave backing hole on the backside, resulting in a slight increase in the overall load-bearing thickness. The introduction of the concave backing hole led to distinct microstructural zones compared to joints welded without it. The resulting joint microstructure comprised five regions: the nugget zone, a recrystallized zone, a shoulder-affected zone, the thermo-mechanically affected zone, and the heat-affected zone. Significantly, this process eliminated the poorly consolidated ‘filling zone’ often associated with conventional plug repairs. The microhardness across the joints was generally slightly higher than that of the base metal (BM), with the concave backing hole technique having minimal influence on overall hardness values or their distribution. However, under identical welding parameters, joints produced using the concave backing hole consistently demonstrated higher tensile strength than those without. The joints displayed pronounced ductile fracture characteristics. A maximum ultimate tensile strength of 278.10 MPa, equivalent to 89.71% of the BM strength, was achieved with an elongation at fracture of 9.02%. Analysis of the grain structure revealed that adjacent grain misorientation angle distributions deviated from a random distribution, indicating dynamic recrystallization. The nugget zone (NZ) possessed a higher fraction of high-angle grain boundaries (HAGBs) compared to the RZ and TMAZ. These findings indicate that during the SAH-FPW process, the use of a concave backing hole ultimately enhances structural integrity and mechanical performance. Full article