Search Results (1,484,244)

This review summarizes studies dedicated to the assessment of microvascular function based on microcirculatory oscillations monitored by the Flow-Mediated Skin Fluorescence (FMSF) technique. Two approaches are presented. The first approach uses oscillatory parameters measured under normoxic conditions, expressed as flowmotion (FM), vasomotion (VM), and the normoxia oscillatory index (NOI). These parameters have been used for the identification of impaired microcirculatory oscillations associated with intense physical exercise, post-COVID syndrome, psychological stress, and erectile dysfunction. The second approach involves characterization of the microcirculatory response to hypoxia based on the measurement of hypoxia sensitivity (HS). The HS parameter is used to characterize microvascular complications in diabetes, such as diabetic kidney disease and diabetic foot ulcers. Based on research conducted by the authors of this review, the FMSF parameter ranges characterizing microvascular function are presented. The diagnostic approach to assessing microvascular function based on flowmotion monitored by the FMSF technique has a wide range of applications and the potential to be integrated into widespread medical practice. Full article

Background: Obesity is a global issue, the development of which depends on many interacting factors. Among these, hormones secreted in the gastrointestinal tract play an important role. The aim of this review was to assess the impact of these hormones on the functions of adipose tissue. Methods: The analysis was based on the latest research concerning both adipose tissue and gastrointestinal hormones. Results: It was found that these hormones can significantly affect adipose tissue, both directly and indirectly. Some hormones, when secreted in excess, can stimulate adipose tissue formation processes, while others can inhibit them. The impact of hormones depends on the location and type of adipose tissue as well as the physiological state of the body. It should also be noted that no hormone acts in isolation but in close cooperation with other factors. Conclusions: The relationship between gastrointestinal hormones and adipose tissue, and their role in obesity, is a complex and evolving field of study. Further research is necessary, particularly into the interactions between hormones and other factors, as well as their mutual interactions. Full article

In this paper, we present the design and fabrication of a novel chip-on-tip catheter, which uses a microcamera and optical fibres to capture in vivo images in a beating porcine heart thanks to a saline flush to clear the blood field. Here, we demonstrate the medical utility and mechanical robustness of this catheter platform system, which could be used for other optical diagnostic techniques, surgical guidance, and clinical navigation. We also discuss some of the challenges and system requirements associated with developing a miniature prototype for such a study and present assembly instructions. Methods of clearing the blood field are discussed, including an integrated flush channel at the distal end. This permits the capture of images of the endocardial walls. The device was navigated under fluoroscopic guiding, through a guiding catheter to various locations of the heart, where images were successfully acquired. Images were captured at the intra-atrial septum, in the left atrium after a trans-septal cross procedure, and in the left ventricle, which are, to the best of our knowledge, the first images captured in an in vivo beating heart using endoscopic techniques. Full article

Fabry disease (FD) is an X-linked lysosomal disease whose ultimate consequences are the accumulation of sphingolipids and subsequent inflammatory events, mainly at the endothelial level. The outcomes include different nervous system manifestations as well as multiple organ damage. Despite the availability of known biomarkers, early detection of FD remains a medical need. This study aimed to develop an in silico model based on machine learning to identify candidate vascular and nervous system proteins for early FD damage detection at the cellular level. A combined systems biology and machine learning approach was carried out considering molecular characteristics of FD to create a computational model of vascular and nervous system disease. A data science strategy was applied to identify risk classifiers by using 10 K-fold cross-validation. Further biological and clinical criteria were used to prioritize the most promising candidates, resulting in the identification of 36 biomarker candidates with classifier abilities, which are easily measurable in body fluids. Among them, we propose four candidates, CAMK2A, ILK, LMNA, and KHSRP, which have high classification capabilities according to our models (cross-validated accuracy ≥ 90%) and are related to the vascular and nervous systems. These biomarkers show promise as high-risk cellular and tissue damage indicators that are potentially applicable in clinical settings, although in vivo validation is still needed. Full article

Sinkhole formation caused by leaking pipes in karst soluble rocks is a significant concern, leading to infrastructure damage and safety risks. In this paper, an experiment was conducted to investigate sinkhole formation in dense sand induced by a leaking pipe. Fibre Bragg grating (FBG) sensors were used to record the strain. A balloon was gradually deflated within a bed of wet silica sand to create an underground cavity. Eighteen FBG sensors, with a wavelength range between 1550 nm and 1560 nm, were embedded horizontally and vertically in the physical model at different levels to monitor deformation at various locations. A leaking pipe was installed to induce the collapse of the formed arch above the cavity. The strain measurements suggested the following four phases in the sinkhole formation process: (1) cavity formation, (2) progressive weathering and erosion, (3) catastrophic collapse, and (4) subsequent equilibrium conditions. The results showed differences in the strain signatures and distributions between the horizontal and vertical measurements. During the critical phase of the sinkhole collapse, the horizontal measurements primarily showed tension, while the vertical measurements indicated compression. This investigation demonstrates the effectiveness of FBGs as advanced monitoring tools for sinkhole precursor identification. The study also suggests using FBGs in geotechnical monitoring applications to improve the understanding and mitigation of sinkholes and related geohazards. Full article

The energy sector in Poland is primarily based on fossil fuels, mainly coal. Hard coal mining is one of the most important industries in Poland. Hard coal deposits in Poland are found in three basins, but mining is currently carried out in the Upper Silesian Coal Basin (USCB) and the Lublin Coal Basin (LCB). The Upper Silesian Coal Basin is Poland’s central hard coal basin, with the most significant coal production extending across Poland and the Czech Republic. Approximately 80% of proven hard coal resources in Poland are found in the Upper Silesian Coal Basin (USCB). There is a tremendous amount of water in active and abandoned hard coal mines, which must be drained daily. Relatively high temperatures characterize mine water. This study analyzed the geological and hydrogeological conditions of the Upper Silesian Coal Basin and determined the potential for the use of mine waters for energy purposes. Depending on the location of the mine, the volume of mine water inflow ranges from 1 to 60 m³/min. The temperature of the pumped water is between 13 and 25 °C. In Poland, several such pilot installations have already been created; it is worth taking a closer look at the following examples. Heat recovery from mine drainage water can significantly reduce atmospheric emissions, which is particularly important in mining areas affected by low emissions. Therefore, Poland must raise the issue of using mined water for energy purposes, especially when making decisions related to decommissioning mines and developing post-mining areas. Full article

Joint attention (JA), a core deficit in children with autism spectrum disorder (ASD), is crucial for social interaction, emotional understanding, and cognitive development. This study aims to compare and analyze the eye-tracking data of ASD and typically developing children (TDC) during virtual games, exploring how different cue types affect JA performance in ASD children. A total of 31 TDC and 40 ASD children participated in the study. Using eye-tracking devices, we recorded the children’s eye movements as they played virtual games, selecting the correct target based on cues provided by virtual characters. Our findings revealed that different cue types significantly impacted the game scores of ASD children but had no significant effect on TDC, highlighting a notable disparity between the two groups. ASD children showed a lower fixation frequency, irregular fixation paths, and increased attention to non-target objects compared to TDC. Interestingly, among the three cue types, ASD children exhibited a preference for the third type, leading to longer fixation on the region of interest and higher game scores. These results underscore the importance of cue selection in enhancing JA in ASD children. This study provides novel insights into the JA deficits in ASD children and offers a scientific basis for the development of targeted and individualized intervention programs. Full article

Helium ions implanted into metals can form ordered bubbles that are isomorphic to the host lattice. While long-range elastic interactions are generally believed to drive bubble superlattice formation, the interactions between individual helium solutes are not yet fully understood. Our first-principles calculations reveal that in molybdenum, Friedel oscillations induced by individual helium atoms generate potential barriers and wells that influence helium pairing and clustering at short He-He distances. These repulsive and attractive interactions at high concentrations provide thermodynamic driving forces that align randomly distributed helium atoms into Mo-He superlattices. Friedel oscillations may have broad impacts on solute–solute interactions in alloys. Full article

Epitranscriptomics is the study of modifications of RNA molecules by small molecular residues, such as the methyl (-CH₃) group. These modifications are inheritable and reversible. A specific group of enzymes called “writers” introduces the change to the RNA; “erasers” delete it, while “readers” stimulate a downstream effect. Epitranscriptomic changes are present in every type of organism from single-celled ones to plants and animals and are a key to normal development as well as pathologic processes. Oncology is a fast-paced field, where a better understanding of tumor biology and (epi)genetics is necessary to provide new therapeutic targets and better clinical outcomes. Recently, changes to the epitranscriptome have been shown to be drivers of tumorigenesis, biomarkers, and means of predicting outcomes, as well as potential therapeutic targets. In this review, we aimed to give a concise overview of epitranscriptomics in the context of neoplastic disease with a focus on N¹-methyladenosine (m¹A) modification, in layman’s terms, to bring closer this omics to clinicians and their future clinical practice. Full article

Background: The study aimed to evaluate the immediate effect of Heat-Compression-Therapy with Game Ready equipment (GR-HCT) on biomechanical properties at different treatment times. Reducing the duration of stimulation through HCT can help optimize recovery processes in sports. Methods: Twenty male MMA fighters (26.5 ± 4.5 years, BMI 24.75 ± 3.0, training experience: 10.3 ± 5.0 years) performed two experimental sessions: (a) 5 min heat-compression therapy (HCT) stimulation (GR-HCT-5); and (b) 10 min heat-compression therapy (GR-HCT-10). All registered parameters, tissue perfusion (PU), tissue temperature (°C), muscle tone (T-Hz) stiffness (S—N/m), elasticity (E—arb), pressure pain threshold (PPT—N/cm) and isometric muscle strength (Fmax—kgf), were measured at rest (r—2 min before GR-HCT stimulation) and 1 min after GR-HCT (p-post) for the flexor carpi radialis muscle (MFCR) and the brachioradialis muscle (MBR). Results: The Friedman’s test for MBR revealed significant differences between GR-HCT5min vs. GR-HCT10min for PU (p < 0.0001), S (p = 0.008), and for MBR and MFCR for °C (p < 0.0001). The pairwise comparisons for PU, S, and °C showed significant differences between rest vs. post values for 5 min as well as between rest vs. post values for 10 min. Further, there was a significant interaction effect (5 min-10 min × Rest-Post p < 0.0001) for PU for MFCR. The post hoc comparison for the interaction effect showed significantly higher PU for post- compared to premeasurement in 5 min PU and 10 min PU (p < 0.001). Further, there was a significant main effect of condition for Fmax both for MFCR and MBR (5 min vs. 10 min p < 0.001); The post hoc comparison for the main effect of condition showed a significantly higher Fmax for post- compared to premeasurement in 5 min and 10 min (p < 0.001). Further, there was a significant main effect of condition for pressure pain threshold [N/cm] both for MFCR and MBR and for T for MBR time of measurement rest vs. post (p < 0.001; p = 0.006; p < 0.001, respectively). The post hoc comparison for the interaction effect showed a significantly lower PPT for post vs. rest in 5 min (p < 0.001 only for MFCR) and in 10 min (p < 0.001). The delta values for PU (post-rest) and ΔTemp °C showed significant differences between the 5 min and 10 min conditions (MFCR; p < 0.0001); (MBR p < 0.001) and (MFCR p < 0.0001); (MBR p < 0.001). Conclusion: Our results show that GR-HCT significantly affects recovery of muscle biomechanical parameters, pain threshold, strength, tissue perfusion, and temperature. Our findings show that a 5 min effect can be sufficient when compared to a 10 min one which is a clue for designing effective recovery protocols. Full article

This paper presents a novel reference model designed to optimize the integration of preventive and predictive maintenance strategies for offshore wind farms (OWFs), enhancing operational decision-making. The model’s flexible and declarative architecture facilitates the incorporation of new constraints while maintaining computational efficiency, distinguishing it from existing methodologies. Unlike previous research that did not explore the intricate cost dynamics between predictive and preventive maintenance, our approach explicitly addresses the balance between maintenance expenses and wind turbine (WT) downtime costs. We quantify the impacts of these maintenance strategies on key operational metrics, including the Levelized Cost of Energy (LCOE). Using a constraint programming framework, the model enables rapid prototyping of alternative maintenance scenarios, incorporating real-time data on maintenance history, costs, and resource availability. This approach supports the scheduling of service logistics, including the optimization of vessel fleets and service teams. Simulations are used to evaluate the model’s effectiveness in real-world scenarios, such as handling the maintenance of up to 11 wind turbines per business day using no more than four service teams and four vessels, achieving a reduction in overall maintenance costs in simulated case of up to 32% compared to a solution that aims to prevent all downtime events. The prototype implementation as a task-oriented Decision Support System (DSS) further shows its potential in minimizing downtime and optimizing logistics, providing a robust tool for OWF operators. Full article

Objectives. Oral mucositis (OM) is a common adverse reaction associated with chemotherapy. We conducted a six-month longitudinal study to estimate the cumulative incidence of OM during the first six months of chemotherapy in adult patients with cancer other than head and neck cancer. Secondary objectives were as follows: (a) to scrutinize the oral health status of these patients and its evolution during chemotherapy, as assessed by oral health indices; (b) to estimate adherence to prescribed oral hygiene protocol during chemotherapy; and (c) to analyze ulceration-free survival in these patients. Methods. Sixty-four patients participated. Dental health and oral hygiene were assessed at baseline and at the end. Every month, blood tests were performed and oral lesions were recorded. This study was observational, with the only intervention being instruction in the hygiene protocol. The cumulative incidence of OM was estimated with the patient as the unit of analysis. A repeated measures ANOVA was applied to analyze the monthly blood test results. Ulceration-free survival analysis was conducted with adherence to the oral hygiene protocol as a grouping factor, followed by Cox proportional-hazards regression. Results . The six-month cumulative incidence rate was 43.75%, 95%CI (31.58–56.67%) for OM grade 2 or higher. The hazard ratio of ulceration associated with adherence to the hygiene protocol was 0.154, 95%CI (0.049–0.483), adjusted for age, sex, baseline hygiene index, and class of treatment. Conclusions. Compliance with hygiene recommendations would decrease the OM risk by more than six times, compared to non-compliance. Full article

Currently, the technology of imparting the necessary reflective properties to a surface is becoming increasingly important. Darkening the surface and matting it helps to diffuse the reflected beam and prevent glare. The surface’s reflective properties are determined by its microstructure. Modern pico- and femtosecond lasers make it possible to obtain surfaces with high precision and create various LIPSS (laser-induced periodic surface structure) types. In this article, we describe the process of formation of a complex two-periodic microstructure on the surface of AISI 321 stainless steel under the influence of radiation from femtosecond lasers and describe the process of scattering of a light beam by the resulting surface. Modeling shows that the presence of an additional transparent coating on a flat surface does not improve its scattering properties and does not eliminate glare. In the event that a complex two-periodic structure is formed on the reflective surface and the coating surface, the nature of the reflection has a clearly defined scattered character, regardless of the angle of incidence of the light beam. This study shows the feasibility and effectiveness of forming a two-periodic structure in order to give it stealth characteristics and reduce visibility. Full article

Future 6G networks will inherit and develop Network Function Virtualization (NFV) architecture. With the NFV-enabled network architecture, it becomes possible to establish different virtual networks within the same infrastructure, create different Virtual Network Functions (VNFs) in different virtual networks, and form Service Function Chains (SFCs) that meet different service requirements through the orderly combination of VNFs. These SFCs can be deployed to physical entities as needed to provide network functions that support different services. To meet the highly dynamic service requirements in the future 6G Internet of Things (IoT) scenario, the highly flexible and efficient SFC reconfiguration algorithm is the key research direction. Deep-learning-based algorithms have shown their advantages in solving this type of dynamic optimization problem. Considering that the efficiency of the traditional Actor Critic (AC) algorithm is limited, the policy does not directly participate in the value function update. In this paper, we use the Proximal Policy Optimization (PPO) clip function to restrict the difference between the new policy and the old policy, to ensure the stability of the updating process. We combine PPO with AC, and further bring the historical decision information as the network knowledge to offer better initial policies, to accelerate the training speed. We also propose the Knowledge = Assisted Actor Critic Proximal Policy Optimization (KA-ACPPO)-based SFC reconfiguration algorithm to ensure the Quality of Service (QoS) of end-to-end services. Simulation results show that the proposed KA-ACPPO algorithm can effectively reduce computing cost and power consumption. Full article

Planar catechin (PCat), a natural antioxidant with a fixed 3D catechin structure on a plane, exhibits radical-scavenging activity approximately five times stronger than the conventional catechin. We synthesized a compound, PCat-TrOH, by binding Trolox (TrOH), an α-tocopherol analog, to PCat to enhance its antioxidant effect against oxidative stress, such as lipid peroxidation. TrOH shows radical-scavenging activity about 6.5 times greater than PCat, and PCat-TrOH exhibited a similar level of radical-scavenging activity to TrOH. Additionally, PCat-TrOH demonstrated twice the radical-scavenging activity against reactive oxygen species compared to PCat or TrOH. This compound is also expected to exhibit an excellent antioxidant effect against lipid peroxidation caused by radical chain reactions, through interactions with vitamin C, similar to that in the case of α-tocopherol. Full article