Search Results (138)

Polyurethanes (PUs) are widely used in biomedical applications; however, their surface properties critically determine bacterial colonization and cell response. In this study, medical-grade PU films were modified using low-pressure C₃H₂F₄ plasma (50 W, 300 s, 0.2 mbar), and the resulting changes in surface chemistry, wettability, topography, bacterial adhesion, and cell compatibility were evaluated. X-ray photoelectron spectroscopy (XPS) analysis confirmed the incorporation of fluorine-containing groups (CF₂, CF₃) and the appearance of an F 1s signal at ~688.3 eV. Plasma treatment increased the water contact angle from 92.6° ± 5.6° to 97.9° ± 3.1° and elevated the root mean square (RMS) surface roughness (Sq) from 39.0 nm to 77.3 nm. Surface free energy slightly decreased after plasma treatment due to reductions in both polar and dispersive components. Quantitative adhesion assays revealed strain-dependent effects. For S. aureus DSM 4910, S. epidermidis DSM 28319, and P. aeruginosa DSM 22644, no consistent reduction in adhesion was observed on plasma-treated surfaces. In contrast, E. coli DSM 18039 demonstrated significantly higher adhesion on modified PU at all incubation times, reaching 5.96 ± 0.44 logCFU/mL after 240 min compared to 5.05 ± 0.27 log colony-forming units per milliliter (logCFU/mL) on unmodified PU. Fluorescence microscopy confirmed increased surface coverage by E. coli on fluorinated samples. Biocompatibility studies using A549 cells showed no cytotoxic effects. Cell spreading area remained comparable between surfaces (1188.6 vs. 1185.1 µm²; p = 0.958). However, cells on plasma-treated PU exhibited reduced major axis length (38.6 vs. 46.7 µm; p < 0.001) and decreased focal adhesion area (8.88 vs. 10.94 µm²; p = 0.002), indicating moderate alterations in cell morphology without compromised viability. These results demonstrate that C₃H₂F₄ plasma fluorination moderately increases PU hydrophobicity and nanoscale roughness, induces strain-dependent changes in bacterial adhesion—particularly enhancing E. coli colonization—while fully preserving mammalian cell viability and showing no cytotoxic effects of the modified surface. Full article

Spectral interrogation of fiber Bragg gratings (FBGs) in the ~850 nm band remains relatively uncommon, largely due to the limited availability of commercial instruments and the restricted applicability of conventional interrogation schemes in this wavelength range. This work presents a practical and high-precision wavelength demodulation method for 850 nm FBG sensing based on an imaging Charge-Coupled Device (CCD) spectrometer. A Czerny–Turner (C–T) optical configuration is employed for spatial spectral dispersion, and the optical system is theoretically analyzed and optimized using ZEMAX to balance spectral resolution, optical throughput, and compactness. A polynomial wavelength–pixel calibration model is established, and Gaussian fitting is adopted for robust peak-position extraction under multimode fiber conditions. Experimental validation is carried out using four serially cascaded FBGs distributed over 830–880 nm. The wavelength–pixel calibration yields an RMS residual of 0.46 nm. Within a strain range of 0–2000 με, the average wavelength demodulation bias of a single FBG is 6.8 pm, with a wavelength demodulation RMS error of 86.9 pm and a measured strain sensitivity of 0.72 pm/με. The results demonstrate that the proposed CCD-based imaging interrogation scheme is feasible for 850 nm FBG sensing and enables accurate wavelength demodulation in this relatively underexplored band. Since the system is implemented using standard off-the-shelf components, it also provides a practical technical route for the deployment of FBG sensing systems in engineering applications. Full article

The formulation of rhizobial bioinoculants remains a critical bottleneck for the large-scale deployment of biological nitrogen fixation in sustainable agriculture, mainly due to limitations in the stability and viability of conventional liquid products. In this study, a spray-drying-based process was developed and optimized to produce a stable and functional bioinoculant using Ensifer meliloti Rm8530, an EPS II–producing strain with enhanced stress tolerance. Strain robustness was evaluated through thermal and osmotic stress assays, together with growth performance across relevant temperature and pH ranges. Six carrier-based formulations combining polysaccharides and proteins were then tested under controlled spray-drying conditions. Process performance was assessed in terms of powder recovery, residual moisture, bacterial survival, yield, and storage stability over 16 weeks. The morphological integrity of spray-dried particles and rehydrated cells was analyzed by scanning electron microscopy. The biological functionality of selected formulations was subsequently validated in planta using alfalfa as a host model. Among the formulations tested, a mixed alginate–gum Arabic matrix showed the best overall balance between process efficiency, post-drying viability, long-term stability, and symbiotic performance. Spray-dried cells retained the ability to induce nodulation and support early plant responses under the conditions evaluated. These results demonstrate that spray drying, combined with appropriate strain selection and formulation design, constitutes a viable and scalable platform for producing stable, functional rhizobial bioinoculants. Full article

Efficient energy harvesting from open-channel flows offers a sustainable solution for powering distributed sensing systems in water infrastructure. This study investigates a piezoelectric wake-excited membrane vortex-induced vibration (VIV) energy harvester through a combined numerical and mechanical approach. The device features an upstream cylindrical bluff body that generates a periodic vortex street, exciting a downstream flexible membrane equipped with surface-mounted piezoelectric patches. A one-way coupled CFD–FEM framework implemented in ANSYS was employed to assess the effects of membrane length, material stiffness, and flow conditions on hydrodynamic loading, structural deformation, and deformation power. Results show that membrane length mainly affects oscillation amplitude and force levels, whereas material stiffness has a stronger influence on membrane deformation and RMS mechanical power. Among the investigated materials, low-stiffness polyethylene yields the highest deformation power, while none of the analysed configurations reaches a full lock-in condition within the explored parameter range. Complementary mechanical analysis revealed that the stiffness of commercial piezoelectric patches significantly reduces local strain, thereby constraining the practically harvestable energy in the present baseline configuration. Spectral power density analysis identified the dominant shedding frequency and its harmonics, confirming that the flow response is governed by a coherent periodic excitation. These findings highlight key design trade-offs in wake-excited membrane harvesters and provide useful guidance for the future optimisation of self-powered hydraulic monitoring systems. Full article

This work presents the results of an integrated monitoring of soil radon gas and seismic activity at Mt. Etna from August 2023 to May 2025, aimed at enhancing comprehension of magma migration and eruption dynamics. Radon data were collected using a permanent station with an alpha particle probe, aggregated hourly. The INGV-OE network monitored seismic activity at 100 Hz; volcanic tremor was analyzed using Root-Mean-Square (RMS) values from the Serra La Nave station. Earthquakes were located using the Hypoellipse algorithm and a 1D crustal velocity model. A robust correlation was found between radon and RMS anomalies, with the former preceding the latter with increasing probability over time (e.g., 30.1% within 1 day, 46.4% within 3 days). Correlations were also found between radon anomalies and Strombolian activity at the summit craters (e.g., 23.8% within 1 day for the Central Crater), suggesting a potential predictive role for radon. Conversely, correlations with paroxysmal events were weaker in the short term but increased over longer time windows. No clear correlation was found between radon anomalies and seismic strain release, likely due to differing temporal resolutions. These results support the idea that radon plays a role as a short-term precursor in volcanic unrest. Full article

Background/Objectives: Luteinizing hormone-releasing hormone agonists (LHRHa) are widely used to induce ovarian suppression in premenopausal women with hormone receptor-positive breast cancer. Although effective, abrupt medical menopause may negatively affect sexual health and intimate partner interactions. Sexual coercion—ranging from manipulation to explicit pressure—remains an underrecognized psychosocial burden in oncology. This multicenter study aimed to evaluate the association between LHRHa therapy and sexual coercion, including relational dynamics measured through the Sexual Coercion in Intimate Relationships Scale (SCIRS). Methods: This cross-sectional study included 81 premenopausal breast cancer patients receiving endocrine therapy at three tertiary centers in Türkiye. Participants were categorized into tamoxifen monotherapy users (n = 39) and LHRHa users (n = 42). Sexual coercion was assessed using the validated Turkish SCIRS, which includes Resource Manipulation/Violence, Defection Threat, and Commitment Manipulation domains. Mann–Whitney U, Kruskal–Wallis, and ANCOVA analyses were performed, adjusting for age, treatment duration, surgery type, chemotherapy, radiotherapy, and education level. The study was ethically approved (2023-KAEK-148) and prospectively registered (NCT06840847). Results: LHRHa users demonstrated significantly higher SCIRS scores across all domains compared with non-users (RM/V: p = 0.039; DT: p = 0.001; CM: p < 0.001; Total: p = 0.004). ANCOVA confirmed LHRHa therapy as an independent predictor after adjusting for covariates (p = 0.001–0.006). The largest effect was observed in the Commitment Manipulation domain (partial η² = 0.177). Younger patients (≤ 36 years) reported significantly greater coercion exposure across all domains (p = 0.018–0.042). Conclusions: LHRHa therapy is associated with increased sexual coercion and strained relational dynamics in premenopausal breast cancer patients, particularly among younger women. These findings emphasize the need for routine sexual health assessment, confidential psychosocial screening, and age-sensitive supportive interventions in endocrine therapy management. Full article

Background/Objectives: Sheep pox, a highly contagious disease, is prevalent in Africa and Asia, with sporadic outbreaks in Europe, and inflicts tremendous economic losses. Vaccination represents the primary and most effective prevention method. The genetic diversity of circulating SPPV strains worldwide is poorly studied, and vaccine selection is typically guided by the availability of a particular vaccine. In this study, four sheep pox vaccines, including the RM65, KSGP 0240, KSGP ARRIAH, and NISKHI ARRIAH vaccines, were evaluated against a contemporary virulent strain circulating in Asia. Methods: The level of antibodies in the blood serum was determined using the ELISA and microneutralization assay. Blood samples and nasal swabs were obtained for PCR examination. Comprehensive clinical and postmortem pathological examinations were conducted. Results: The body temperature of all experimental animals remained within the physiological norm, with no clinical manifestations, local reactions, viremia, or necropsy pathological lesions, demonstrating the effectiveness and safety of the vaccines used against the contemporary virulent strain. Furthermore, immunization was associated with the formation of neutralizing and specific antibodies in all vaccinated groups post vaccination, with a significant increase in their levels after challenge, indicating a high level of immunogenicity. The NISKHI ARRIAH vaccine exhibited statistically significant superiority over the other vaccinated groups. However, the unvaccinated control group demonstrated post-challenge moderate-to-severe clinical signs, postmortem lesions, with high levels of virus shedding, and lower levels of neutralizing and specific antibodies, compared with the vaccinated groups. Conclusions: Our study results indicate that the experimental group immunized with the NISKHI ARRIAH vaccine exhibited the initial and most substantial immune response, maintaining the highest antibody levels on the 28th day after vaccination in comparison to the other studied vaccines. Full article

The concept of using ‘acid-adapted’ challenge cultures in the microbial validation of food processes that incorporate an acidic treatment is that they would be more resistant to acid and require a robust process to obtain targeted log reductions. The recent confirmation that acid-adapted Salmonella challenge cultures for droëwors and biltong processes are more sensitive to those processes than non-adapted cultures changes that preference for the use of non-adapted cultures for validation studies with these specific processes. However, it is difficult to achieve > 5-log reductions with non-adapted cultures, one of two USDA-FSIS parameters available for validation of processes that are not aligned with traditional process conditions for dried beef products in the USA (i.e., beef jerky). A natural multipurpose (flavor, antimicrobial) commercial product, described as a refined liquid smoke flavorant, provided >7-log reductions with droëwors when challenged with non-adapted cultures of Salmonella (5-serovar mixture), Shiga toxigenic Escherichia coli (STEC, four-strain mixture), and Listeria monocytogenes (four-strain mixture) as well as a >7-log reduction with biltong processing (vs Salmonella). Comparisons between standard droëwors and biltong processes (all <5-log reductions) using non-adapted challenge cultures vs. the same formulation plus 0.75% pyrolyzed liquid smoke extracts (Flavoset) showed greater and significant (p < 0.05) reductions in duplicate trials with triplicate samples at each sampling point in each trial (total n = 6) when analyzed by repeated measures analysis of variance (RM-ANOVA). Although sold as a flavorant, this study examines the antimicrobial properties of Flavoset 5400L to improve the safety of droëwors and biltong by achieving a >5-log reduction with non-adapted pathogenic challenge cultures. Validation processes for droëwors and biltong established with these parameters should result in greater safety of marinaded, non-thermally processed meats from traditional foodborne pathogens commonly associated with meats or meat processing environments. Full article

Germanium (Ge) has long been regarded as a promising channel material, owing to its superior carrier mobility and highly tunable electronic band structure. The new generation of low-power electronics is approaching the formation of fully depleted (FD) transistors on Si-on-insulator (SOl) and Ge-on-insulator (GOl) substrates. In this work, we present a full process of a novel FDGOI transistor formed on a strained GOI with low defect density. This scalable and industry-compatible approach enables the formation of uniform 50 nm thick Ge layers by using spinning wet etch with ultrasmooth surfaces (RMS roughness = 0.262 nm) and a low etch-pit density of ~10⁵ cm⁻². Electrical measurements reveal excellent carrier transport properties, with back-gate (BG) transistors achieving mobilities of 550–600 cm²/V·s, while front-gate (FG) devices exhibit sharp switching behavior and steep subthreshold slopes, yielding I_ON/I_OFF ratios up to 10⁵. Temperature-dependent measurements further demonstrate a pronounced enhancement of device performance: the I_ON/I_OFF ratio increases to 106, the subthreshold swing (SS) decreases from 179 mV/dec at room temperature to 137 mV/dec at 120 K, and the threshold-voltage shift with temperature is as low as 1.87 mV/K across the range of 30–300 K. Such behavior highlights the potential of band-gap engineering for precise threshold-voltage control. Taken together, these results establish GOI as a CMOS-compatible material platform and provide a solid technological basis for the development of next-generation low-power transistors beyond conventional CMOS scaling. Full article

The growing demand for sustainable construction practices has driven research into self-sensing materials incorporating recycled waste for smart SHM (Structural Health Monitoring) systems. However, previous works did not investigate the influence of rheological behavior and piezoresistive properties of sustainable cementitious sensors containing red mud (RM) on the strain monitoring of concrete beams. To address this gap, this study presents an experimental analysis of the rheological, mechanical, and self-sensing performance of mortars incorporating carbon black nanoparticles (CBN) and varying levels of RM (25–100% sand replacement by volume), followed by their application in monitoring strain in a reinforced concrete beam under dynamic loading. The results showed that increasing RM content led to higher viscosity and yield stress, with a 60% reduction in consistency index. Compressive strength increased by up to 80%, while mortars with RM content higher than 50% showed high electrical conductivity and reversible resistivity changes under load cycles. Mortars containing 50–100% RM demonstrated improved piezoresistive response, with a 23% increase in gauge factor, and the best-performing sensor embedded in a concrete beam exhibited stable and reversible fractional changes in resistivity, closely matching strain gauge data during dynamic loading conditions. These findings highlight the potential of RM-based smart mortars to enhance sustainability and performance in SHM applications. Full article

Autochthonous enterococci surviving mild thermization of raw milk (RM) before traditional Greek cheese processing may simultaneously comprise safe and virulent thermoduric strains with multiple antibiotic resistances (ARs). Therefore, this study biotyped and then compared the ARs of 60 Enterococcus isolates from two antilisterial sheep milks of native Epirus breeds before (RM) and after (TM) thermization at 65 °C for 30 s; the RM isolates were previously genotyped and evaluated for primary safety traits, namely, hemolytic activity, vanA/vanB, cytolysin, and virulence genes, by molecular methods. Biochemically typical and atypical strains of Enterococcus faecium (six biotypes), E. durans (five biotypes), E. faecalis (two biotypes), and E. hirae (one biotype), which were subdominant to other LAB species in RM (19 isolates), prevailed in TM (41 isolates). E. faecium biotypes 1A, 1D, and 1H included multiple-Ent+ (entA/entB/entP or entA/entB) strains with strong antilisterial CFS activity, whereas E. faecium 1X (entA), E. durans 2A, 2B, 2C, and 2X (entA/entP or entP), E. faecalis 3B, and E. hirae 4A (entA) biotypes displayed direct in vitro antilisterial activity only. Biotypes 1D, 1X, and 2A were selected in TM. All E. faecium/durans isolates were susceptible to vancomycin, but the m-Ent + E. faecium biotype 1A and 1D strains were resistant to penicillin, erythromycin, ciprofloxacin, and ampicillin. In contrast, all biotype 1X isolates were susceptible to all antibiotics tested. All E. faecalis and most E. durans isolates were resistant to penicillin but susceptible to erythromycin and ciprofloxacin. Biotype 2X isolates and one virulent (ace; gelE) E. faecalis isolate from RM were tetracycline-resistant. A sporadic RM isolate of E. hirae that was resistant to penicillin and vancomycin was not retrieved from the counterpart TM, but the inclusion of three vancomycin-resistant isolates from TM in the primary biotype 3B of E. faecalis was a cause for concern. In conclusion, based on the results, antibiotic-susceptible representatives of all strain biotypes of the E. faecium/durans group, as well as antagonistic m-Ent+ E. faecium strains from sheep milk that were susceptible to vancomycin and ampicillin and lacking virulence genes, can be included in safe complex natural starters to be developed for onsite use in traditional Greek hard cheese technologies. Full article

Porphyridium purpureum can synthesize a high phycoerythrin content, which has strong potential application in nutrition, pharmaceuticals, and cosmetics. An effective culture strategy is the key to producing biomass of P. purpureum rich in phycoerythrin. However, there are still bottlenecks in the large-scale production of Porphyridium, such as nutrient supplementation and cultivation mode. In this study, P. purpureum SCS-02, isolated from the South China Sea, was used as experimental microalga strain. The effects of different salinity (10, 20 and 34 ppt) and semi-continuous culture on accumulation of biomass and phycoerythrin were investigated. The semi-continuous culture modes include recycled culture medium mode (RM) and fresh culture medium mode (FM). The results showed that low salinity (10 ppt) could enhance the accumulation of phycoerythrin, the content and yield of which were 8.39% DW and 160 mg L⁻¹, respectively. The yield of phycoerythrin of P. purpureum in semi-continuous culture with a 30% renewal rate of fresh culture medium was 253% higher than the batch culture. In summary, the semi-continuous culture strategy with fresh medium renewal under low salinity conditions increased the phycoerythrin yield to 641.47 mg after 30 days of cultivation, while exopolysaccharide accumulation was significantly reduced compared with batch culture. These results provide useful reference for optimizing culture strategies of P. purpureum, and may serve as a basis for future attempts to scale phycoerythrin production under industrially relevant conditions. Full article

Developing highly efficient and cost-effective immobilized biocatalysts is essential for optimizing diacylglycerol (DAG) production via biotransformation of natural oil. To address this, the 1,3-regiospecific MAS1-H108W lipase, derived from marine Streptomyces sp. strain W007, was produced through high-density fermentation (20 °C, pH 7.0, 132 h). This lipase was immobilized by XAD1180 resin adsorption, yielding an immobilized MAS1-H108W lipase with a lipase activity of 4943.5 U/g and a protein loading of 201.5 mg/g under selected conditions (lipase/support ratio 100 mg/g, initial buffer pH of 8.0). After immobilization, the lipase maintained its optimal temperature at 70 °C and shifted its optimal pH from 7.0 to 8.0, along with enhanced thermostability. The immobilized MAS1-H108W lipase demonstrated superior efficiency in DAG synthesis compared to non-regiospecific immobilized MAS1 lipase and commercial lipases (Novozym 435 and Lipozyme RM IM). Under the optimized reaction conditions (reaction temperature 60 °C, olive oil/glycerol molar ratio 1:2, adding amount of immobilized MAS1-H108W lipase 1.0 wt.%), a maximum DAG content of 49.3% was achieved within 4 h. The immobilized lipase also exhibited excellent operational stability, retaining 81.9% of its initial production capacity after 10 reuse cycles. Furthermore, in the glycerolysis of various vegetable oils (corn oil, rapeseed oil, peanut oil, sunflower oil, and soybean oil), the DAG content catalyzed by immobilized MAS1-H108W lipase consistently exceeded 48%. This work provides a highly efficient and economical immobilized biocatalyst for DAG production, and highlights the significant potential of regioselective lipases in promoting efficient DAG synthesis via glycerolysis. Full article

Type I restriction-modification (RMI) systems play a crucial role in bacterial defense against mobile elements by distinguishing self and foreign DNA through sequence-specific methylation and cleavage. Here, we characterize BlihIA, a novel RMI system from Bacillus licheniformis DSM13 which features redundancy in its hsdS gene copies. Using ONT sequencing, we identify the bipartite recognition site of BlihIA as RTAC(N)₅GCT. We demonstrate the system’s activity both in vivo through efficiency of plaquing (EOP) assay and in vitro in a nuclease reaction with purified BlihIA complex. Notably, mutation of the recognition site abolished in vitro DNA cleavage, confirming sequence specificity. Furthermore, we show that the antirestriction protein ArdB from plasmid R64 effectively prevents DNA cleavage by BlihIA, suggesting a direct mechanism of inhibition. This study provides the first functional characterization of a novel RM system BlihIA, extending the diversity of RM systems in Bacillus species and suggesting potential applications for improving genetic transformation in industrial strains. Full article

Objectives: The aim of this study was to assess the safety and feasibility of resistance training (RT) in middle-aged and young individuals by examining cardiocirculatory and metabolic responses to squat performed under low and high external loads as per current exercise prescription guidelines. Methods: Eighteen RT-trained individuals (nine middle-aged individuals, including eight women who were equally distributed) performed a cycling incremental test for the determination of their maximal aerobic capacity and three sessions of RT, respectively, to determine their one repetition maximum (1RM) of squat and their physiological responses during different training protocols of squat with equal training loads (3 × 12 at 55% 1RM vs. 5 × 5 at 80% 1RM). Whole-body metabolic (oxygen update and blood lactate) and cardiocirculatory (heart rate and blood pressure) responses and rate of perceived exertion (RPE) were compared across age groups and % 1RM to determine the metabolic stimulus and cardiovascular strain imposed by this form of training. Results: Young and middle-aged individuals exhibited similar cardiocirculatory responses to RT, with the only exception being a higher diastolic response in the middle-aged group for both protocols (present also at rest). No difference was found between the two age groups in terms of metabolic response and RPE. 80% 1RM induced a similar cardiocirculatory response and a higher RPE but a lower metabolic response compared to 55% 1RM. Conclusions: While no difference in physiological responses was found between the groups, the lower-load and higher-repetition training scheme demonstrated better time efficiency, metabolic activation, and perceived effort with equivalent cardiocirculatory strain. These findings support the safety of RT and can guide practitioners in the design of training protocols. Full article