Search Results (196)

Deposition of intramuscular fat (IM), also known as marbling, is the deciding factor of beef quality grade in the U.S. Defining molecular mechanisms underlying the differential deposition of adipose tissue in distinct anatomical areas in beef cattle is key to the development of strategies for marbling enhancement while limiting the accumulation of excessive subcutaneous adipose tissue (SAT). The objective of this exploratory study was to define the IM and SAT transcriptional heterogeneity at the whole tissue and single-nuclei levels in beef steers. Longissimus dorsi muscle samples (9–11th rib) were collected from two finished beef steers at harvest to dissect matched IM and adjacent SAT (backfat). Total RNA from IM and SAT was isolated and sequenced in an Illumina NovaSeq 6000. Nuclei from the same samples were isolated by dounce homogenization, libraries generated with 10× Genomics, and sequenced in an Illumina NovaSeq 6000, followed by analysis via Cell Ranger pipeline and Seurat in RStudio (v4.3.2) By the expression of signature marker genes, single-nuclei RNA sequencing (snRNAseq) analysis identified mature adipocytes (AD; ADIPOQ, LEP), adipose stromal and progenitor cells (ASPC; PDGFRA), endothelial cells (EC; VWF, PECAM1), smooth muscle cells (SMC; NOTCH3, MYL9) and immune cells (IMC; CD163, MRC1). We detected six cell clusters in SAT and nine in IM. Across IM and SAT, AD was the most abundant cell type, followed by ASPC, SMC, and IMC. In SAT, AD made up 50% of the cellular population, followed by ASPC (31%), EC (14%), IMC (1%), and SMC (4%). In IM depot, AD made up 23% of the cellular population, followed by ASPC at 19% of the population, EC at 28%, IMC at 7% and SMC at 12%. The abundance of ASPC and AD was lower in IM vs. SAT, while IMC was increased, suggesting a potential involvement of immune cells on IM deposition. Accordingly, both bulk RNAseq and snRNAseq analyses identified activated pathways of inflammation and metabolic function in IM. These results demonstrate distinct transcriptional cellular heterogeneity between SAT and IM depots in beef steers, which may underly the mechanisms by which fat deposits in each depot. The identification of depot-specific cell populations in IM and SAT via snRNAseq analysis has the potential to reveal target genes for the modulation of fat deposition in beef cattle. Full article

The ability to model the earliest stages of human embryonic development in vitro using pluripotent stem cells offers researchers new ways to understand and interrogate the intricacies of implantation. It also raises important ethical and regulatory considerations, both those common to research involving human embryos, as well as those unique to stem cell-based embryo and endometrial models. This review examines the underpinning scientific discoveries that have led to the development of this rapidly expanding area of research, and how three-dimensional embryo models could be employed in advancing assisted reproductive technologies and understanding implantation failure. Importantly, we also discuss the ethical and legal implications and explore various governance models that have been proposed to foster responsibility and innovation in this area of research. Given the heightened interest in the scientific community on this topic, we finish on the question of how and when to involve the public in the development of this technology and its regulation. Full article

This study evaluated the effects of mechanical agitation of Aloe vera Barbadensis Miller solution at different concentrations using passive ultrasonic irrigation (PUI), XP Endo Finisher (XPF), XP Clean (XPC), and Easy Clean (ECL), compared to conventional endodontic irrigation (CIE), on bond strength and adhesive failure patterns in the cervical, middle, and apical thirds of the root canal. Aloe vera solutions at 1%, 3%, and 5% were tested to reverse collagen fiber collapse induced by hypochlorous acid, a free radical released by 2.5% sodium hypochlorite, which impairs dentin hybridization and the light curing of resin cement. Fiberglass posts were cemented using an etch-and-rinse adhesive system (Ambar; FGM) and conventional dual resin cement (Allcem Core) in root dentin across all thirds. Human teeth underwent chemical–mechanical preparation, and the Aloe vera solution was agitated using the CIE, PUI, XPF, XPC, or ECL protocols. Slices from each root third were evaluated under a stereomicroscope at 10× magnification and subjected to the push-out test. Cytotoxicity was assessed by applying various Aloe vera concentrations to stem cells from the apical papilla (SCAPs) for 24 h, followed by analysis of cell metabolism (Alamar Blue), viability (Live/Dead), and proliferation (F-actin). Aloe vera demonstrated significant biological activity and enhanced bond strength, particularly at 3% and 5%, irrespective of the agitation method or root third. Thus, it can be concluded that using Aloe vera solution is an alternative for pre-treatment before the cementation of fiberglass posts with conventional dual-cure resin cement in endodontically treated dentin. Full article

Machining Nomex honeycomb composite structures is crucial for manufacturing components that meet stringent industry requirements. However, the complex characteristics of this material require specialized machining techniques to avoid defects, ensure optimal surface quality, and preserve the integrity of the cutting tool. Thus, hybrid ultrasonic-vibration-assisted machining (HUSVAM) technology, using a CZ10 combined cutting tool, was introduced to overcome these limitations. To this end, a 3D numerical model based on the finite element method, developed using Abaqus/Explicit 2017 software, allows us to simulate the interaction between the cutting tool and the thin walls of the structure to be machined. The objective of this study was to validate a numerical model through experimental tests while quantifying the impact of critical machining parameters, including the rotation speed and tilt angle, on process performance, in terms of surface finish, tool wear, cutting force components and chip size. The numerical results demonstrated that HUSVAM technology allows for a significant reduction in the cutting force components, with a decrease of between 12% and 35%. Furthermore, this technology improves cutting quality by limiting the deformation and tearing of cell walls, while extending tool life through a significant reduction in wear. These improvements thus contribute to a substantial optimization of the overall efficiency of the machining process. Full article

Cold stress disrupts broiler homeostasis, and a single intervention may be insufficient for protection. This study examined the effects of early cold conditioning (25 ± 1 °C for 3 h at 5 days) and glutamine (Gln) supplementation on broiler thermotolerance during a 16 ± 1 °C cold challenge at 35 days. A 2 × 3 factorial design assigned 360 Cobb-500 broilers to six treatments (six replicates/treatment, ten birds/replicate) with three Gln levels (0%, 0.3%, and 0.5%) and two temperature conditions: standard temperature and a 7 °C reduction at 5 days old. Supplementing with 0.3% and 0.5% Gln and cold conditioning improved growth performance (p < 0.05), except for feed intake during the grower-finisher phase and overall growth with cold conditioning alone. Adding 0.3% and 0.5% Gln enhanced hemoglobin, total protein, albumin, triiodothyronine (T₃), thyroxine (T₄), antioxidant capacity, catalase (CAT), superoxide dismutase (SOD), heat shock protein 70 (HSP70), interleukin 2 (IL2), IL10, IL4, interferon-γ (INF-γ), and troponin-T levels (p < 0.05). Cold conditioning influenced packed cell volume, T₃, T₄, CAT, HSP70, IL10, INF-γ, and troponin-T levels (p < 0.05). Diet-temperature interaction influenced growth, antioxidant, and immune responses, but not hematological or biochemical indicators. Overall, dietary Gln at 0.3% and 0.5% and early cold conditioning may serve as complementary strategies to mitigate cold stress in broilers. Full article

Humans are in constant contact with clothing and textiles throughout their lives, which can expose them to chemicals present in these materials. Chemicals used in fiber production and in material processing can be absorbed through the skin, ingested, or inhaled, causing allergic reactions. Advancements in modern textiles have made them more versatile and functional for a variety of applications, resulting in the use of more chemicals. Regarding the textile industry, several studies have focused on the environmental impact of its effluents and dyes, and, more recently, several studies have focused on textile waste impact in general. Nevertheless, few studies have been carried out on human cytotoxicity, and very little is known about the dangers of long-term use of textiles. The aim of this work was to review the literature to understand what has been done in the field of textile cytotoxicity. In addition, this work also highlights the existing gap regarding regulation and standardized tests for the analysis of everyday clothing. There is an urgent need to establish regulations and standardize testing protocols to assess the potential cytotoxic effects that may arise from finished textile products before they are marketed, in order to guarantee consumer safety. Full article

Wool textiles with multifunctional properties such as self-cleaning, antibacterial, electrical conductivity, UV blocking etc. have recently attracted interest. Among the materials employed towards their development, carbon nanotubes (CNTs) have been widely investigated due to their unique chemical, mechanical and electrical properties, exhibiting also notable UV-blocking properties. However, their limited dispersibility in solvents, particularly in water, has hindered their extensive industrial application and diminished their significant potential. In this work, two guanidinylated derivatives of hyperbranched polyethyleneimine (GPEI5k and PEI 25K) functionalized oxCNTs (oxCNTs@GPEI5K and oxCNTs@GPEI5K), with exceptional aqueous compatibility and colloidal stability, developed in our recent publication, were evaluated as to their antibacterial activity on Gram (-) Escherichia coli and Gram (+) Staphylococcus aureus bacteria and their cytotoxicity against mammalian cells, and the most promising, i.e., oxCNTs@GPEI5K, was subsequently used as finishing agent of wool fabric. The resulting wool textiles were evaluated for color, wash fastness, antibacterial properties, and UV-blocking performance. The GPEI-functionalized oxCNTs derivative, exhibited uniform distribution and good adhesion onto the wool fabrics yielding multifunctional wool fabrics with sustained antibacterial properties even after multiple washing cycles. Additionally, the modified textiles exhibited improved ultraviolet protection, highlighting their potential for multifunctional applications in antibacterial and UV-shielding textiles. Full article

Background: Adipose tissue growth follows a biphasic process involving both cellular hyperplasia (an increase in adipocyte number) and hypertrophy (an increase in adipocyte size). Rumen-protected fatty acid supplements have been utilized to alter fat deposition, modify the fatty acid composition of meat, and reduce methane emissions. However, limited research has explored how different fatty acid mixtures influence adipose tissue’s biphasic growth phases. Methods: The objectives of this study are to investigate the effects of fatty acid mixtures (seven different mixtures) on: (1) hyperplasia of undifferentiated stromal vascular fraction (SVF) cells, or (2) hypertrophy of chemically differentiated SVF cells isolated from subcutaneous adipocytes of finished steers. Results: Mixtures containing palmitic and linoleic acids stimulated hyperplasia, enhancing the proliferation of undifferentiated SVF cells, while mixtures with oleic acid (50%) predominantly promoted hypertrophy, driving lipid accumulation and adipocyte maturation. Conversely, mixtures composed solely of saturated fatty acids (50% palmitic and 50% stearic acids) exhibited a profound inhibitory effect on both hyperplasia and hypertrophy, underscoring the importance of fatty acid composition in regulating adipogenesis. Conclusions: These findings demonstrate that the composition of fatty acid mixtures directly influences adipogenesis and lipogenesis in vitro, highlighting their potential role in designing tailored rumen-protected supplements for modifying fat deposition in livestock. Full article

In this study, the mechanical behavior of AA6082 foams with Weaire–Phelan (WP) cell structures under compressive loading was analyzed. The foams were produced using the lost-PLA replication method, a cost-effective and straightforward manufacturing technique. A total of six aluminum alloy samples were fabricated and subjected to compression tests to assess both their mechanical performance and the repeatability of the results. The produced foams demonstrated a well-defined morphology and high-quality surface finish, accurately replicating the geometries of the original PLA 3D-printed templates. The experimental density of the foams closely matched theoretical values, confirming the consistency of the replication process. The compressive stress–strain response of the Weaire–Phelan cell foams displayed an initial linear elastic region, followed by three distinct plateau regions with increasing stress levels. The final densification phase occurred when the structure could no longer accommodate further plastic deformation, leading to a sharp increase in the compression load. From the stress–strain data, the specific energy absorption of the foams was calculated. The average specific energy absorption was measured to be 4 J/cm³, with a standard deviation of 0.49 J/cm³ across the six tested samples. These results indicate reliable mechanical performance and reproducibility of the manufacturing process, making these foams suitable for applications requiring energy absorption and lightweight structural components. Full article

Symmetric instruction machines (SIAs) and symmetric Turing machines (STMs) are models of computation involving concepts derived from those of classical Turing machines such as tape (memory) and head (processor), but with different functional and structural characteristics. The former model (SIAs) introduced in this paper and preferred by Mark Burgin is a result of a reformulation of the latter model (STMs) published in several articles by the second author in the past. The properties of both models are analyzed and compared. The word “symmetric” in both cases represents the feature of the design which is distinct from classical Turing machines where only cells on the tape change under the action of the head. In both models, symmetric computing involves changes of the tape and parallel (“symmetric”) changes of instructions listed in the head. The key difference between SIAs and STMs is in the dynamic of the changes, which in the former model has the form of compound one-way actions and in the latter model, it has the form of uniform mutual interactions, which only in specific realizations can be separated into a pair of actions. Because of the untimely passing of Mark Burgin, the discussion of the two models and cooperation on the paper has never been finished. For this reason, the arguments of both authors are reported even though, in some cases, they are mutually inconsistent or even contradictory. Full article

The aim of this study was to determine the load-bearing capacity of Klein’s floors under fire conditions using analytical and numerical analyses. Analytical and numerical simulations were performed considering different structural variants of Klein’s floors. A numerical FEM model was developed in Abaqus to create temperature profiles of the beam-to-beam slabs and steel beams, and the fire load-bearing capacity of Klein’s celling after being exposed to fire for 30, 60, and 120 min was calculated analytically. The analytical method of assessing the fire load-bearing capacity of Klein’s floors uses temperature profiles, which allow for calculations to verify fire resistance in the time domain of different structural variants of Klein’s floors. (1) Introduction: The structural solutions of Klein’s floors are widely known, but no studies in the literature have addressed the mechanics of these elements under fire conditions. Both the beam-to-beam slab and steel beams are sensitive to high temperatures. Providing the required level of fire safety in buildings with Klein’s ceilings is a complex issue that requires detailed analysis. This often involves the assessment of technical and material solutions that are not currently used, and a verification of their fire resistance may be necessary to adapt existing buildings to the presently applicable technical and construction regulations. (2) Methodology: This study was prepared based on domestic and foreign sources, including standards presenting available methods for verifying the fire resistance of Klein’s ceilings in terms of their load-bearing capacity. A calculation scheme was indicated that takes into account the inter-beam slab, treated as a reinforced masonry element subjected to bending, and steel ceiling beams. In addition, this article presents an original method for determining the temperature profiles of individual elements of Klein’s ceilings, based on numerical methods, to determine their reduced values of material properties. The temperature profiles included in this study take into account both different construction variants of Klein’s ceilings and different ways of finishing the lower surface of these ceilings. The presented analytical method of fire load-bearing capacity assessment is supported by a calculation example. (3) Conclusions: The calculation methodology presented in this paper, which is part of the analysis of the fire load-bearing capacity of Klein’s ceilings, allows for a safe estimation of their durability in fire conditions. The presented temperature profiles of individual Klein’s ceiling elements allow for the verification of their fire resistance in terms of load-bearing capacity, in accordance with the literature on the subject. The temperature values of individual Klein’s ceiling elements, presented in the form of a table, depending on the fire duration, indicate that the applied structural solutions of the ceilings have a significant influence on the rate of temperature increase in the partition. Based on the conducted analyses, it was found that steel beams in an unplastered Klein’s ceiling lose their fire load-bearing capacity before the 30 min fire duration, defined by the standard temperature–time curve. The use of gypsum plaster with a thickness of at least 1.5 cm can provide fire resistance of the above elements for up to 120 min of fire duration. It was found that the quality of the plaster is important, influencing its adhesion to the lower surface of the ceiling. The fire resistance of the inter-beam slabs is significantly influenced by the temperature of their reinforcement, which largely depends on the distance of the reinforcement from the lower edge of the slab. Full article

The mechanical behavior of AA6082 Kelvin cell foams under compressive tests has been investigated in this work. The lost-PLA replication technique, a simple and cheap technique, has been adopted as the production method. Six Al alloy samples have been made and successively subjected to compressive tests in order to examine the mechanical response and the repeatability too. The manufactured foams show good morphology and surface finishing, replicating the PLA 3D-printed foams with adequate accuracy. The experimental density of the foam has been found in good agreement with the theoretical one. When subjected to static compression, the Kelvin cell foams exhibit a load–strain diagram characterized by the initial linear stage followed by two plateaus at successively increasing load levels. Final densification occurs when there is no more space available for further plastic deformation and the load sharply increases. The specific absorbed energy has been calculated from load–strain curves: the average measured value was found to be 2.3 J/cm³, and standard deviation in the six compression tests was 0.3 J/cm³. Full article

The surfaces of beech wood samples were treated with polyethylenimine (PEI) solutions at three different concentrations—0.5%, 1% and 2%—and two molecular weights—low molecular weight (LMW) and high molecular weight (HMW). The effects of PEI surface treatment of wood were characterized by FT-IR spectroscopy, the penetration depth of PEI (EPI fluorescence spectroscopy), the bonding position of PEI (by SEM), the wetting and surface energy, and the water uptake. After PEI treatment, the samples were coated with a water-based transparent acrylic coating (WTAC). The dry film thickness, the penetration depth of the coating, the adhesion strength and the surface roughness of the coated wood surface were evaluated. EPI fluorescence and SEM micrographs showed that PEI HMW chains were deposited on the surface, in contrast to PEI LMW, which penetrates deeper into layers of the wood cells. Treatment with a 1% PEI HMW solution resulted in a 72% reduction in water uptake of the wood (compared to untreated samples after 5 min of applying water droplets to the surface) and a 23.2% reduction in surface energy (compared to untreated samples) while maintaining the adhesion strength of the applied WTAC. The lower water uptake of the treated wood samples reduced the roughness of the coated surface, which is particularly important when the wood surface is finished with water-based coatings. Full article

Human pluripotent stem cells (hPSCs) attract tremendous attention due to their unique properties. Manual extraction of trajectories of cell colonies in experimental image time series is labor intensive and subjective, thus the aim of the work was to develop a computer semi-automated protocol for colony tracking. The developed procedure consists of three major stages, namely, image registration, object detection and tracking. Registration using discrete Fourier transform and tracking based on the solution of a linear assignment problem was implemented as console programs in the Python 3 programming language using a variety of packages. Object detection was implemented as a multistep procedure in the ProStack in-house software package. The procedure consists of more than 40 elementary operations that include setting of several biologically relevant parameters, image segmentation and performing of quantitative measurements. The developed procedure was applied to the dataset containing bright-field images from time-lapse recording of the human embryonic cell line H9. The detection step took about 6 h for one image time series with a resolution of 2560 by 2160; about 1 min was required for image registration and trajectories extraction. The developed procedure was effective in detecting and analyzing the time series of images with “good” and “bad” phenotypes. The differences between phenotypes in the distance in pixels between the starting and finishing positions of trajectories, in the path length along the trajectory, and the mean instant speed and mean instant angle of the trajectories were identified as statistically significant by Mann–Whitney and Student’s tests. The measured area and perimeter of the detected colonies differed, on average, for different phenotypes throughout the entire time period under consideration. This result confirms previous findings obtained by analyzing static images. Full article

This study analyzes the influence of energy generated by emitters on the adhesive properties of varnish coatings in multilayer UV systems. The experimental material, in the form of a cell board finished with UV varnish products, was prepared on a prototype line under the conditions of Borne Furniture in Gorzów Wielkopolski. The roughness and wettability were measured using a OneAttension tensiometer integrated with a topographic module, taking into account the Wenzel coefficient. The adhesion of the examined systems was verified using the PositiTest AT-A automatic pull-off device. Energy consumption by the prototype production line was compared to the standard line, utilizing mercury emitters and mercury emitters with added gallium. Energy consumption was calculated for selected variants. The influence of the Wenzel coefficient on the wettability angle was observed. Significant differences between contact angles (CA and CAc) were noted for coatings formed with sealers (stages I and II). The largest discrepancies, reaching up to 30 degrees, were recorded at the lowest UVA and UVV doses of 26 mJ/cm². In adhesion tests, values below 1 MPa were obtained. Insufficient energy doses in the curing process of UV systems led to delamination between the coatings. Five variants were selected where delamination within the substrate predominated (˃90% A) and were characterized by the lowest energy consumption in the processes. Topographic images helped identify the presence of various surface microstructures at different stages of the production cycle. The greatest energy savings, up to 50%, were achieved in stages III and IV of the technological process. Full article