Search Results (1,131)

Fiber Bragg Grating (FBG) sensors facilitate compact, multiplexed, and electromagnetic interference-immune monitoring in embedded and harsh environments. The removal of the polymer jacket, a measure taken to withstand elevated temperatures or facilitate integration, exposes the fragile glass. This underscores the necessity of functional coatings, which are critical for enhancing durability, calibrating sensitivity, and improving compatibility with host materials. This review methodically compares coating materials and deposition routes for FBGs, encompassing a range of techniques including top-down physical-vapor deposition (sputtering, thermal/e-beam evaporation, cathodic arc), bottom-up chemical vapor deposition (CVD)/atomic layer deposition (ALD), wet-chemical methods (sensitization/activation, electroless plating (EL), electrodeposition (ED)), fusion-based processes (casting and melt coating), and hybrid stacks (e.g., physical vapor deposition (PVD) seed → electrodeposition; gradient interlayers). The consolidation of surface-preparation best practices and quantitative trends reveals a comprehensive understanding of the interrelationships between coating material/stack, thickness/microstructure, adhesion, and sensitivity across a range of temperatures, extending from approximately 300 K to cryogenic regimes. Practical process windows and design rules are distilled to guide method selection and reliable operation across cryogenic and high-temperature regimes. Full article

Acne is a multifactorial skin condition characterized by an infection in the pilosebaceous units in the skin. Patients with acne suffer from comedones, papules, pustules and nodules or cysts in severe cases. These clinical features might cause disfigurmentation, depression, anxiety and significantly impact the quality of life of patients. Systemic and continuous exposure of antibiotics put patients at risk of developing systemic toxicity, bacterial resistance and gut dysbiosis. Microneedles offer an innovative approach of providing targeted topical delivery of minocycline while insuring efficient permeation through skin layers. Methods: minocycline microneedles were formulated using casting method and characterized for insertion ability, mechanical strength, drug content, antibacterial activities, deposition and dissolution behavior using ex vivo full-thickness rat skin. Results: Insertion tests confirmed effective skin penetration and mechanical integrity with only 9.5% height reduction. Drug content was 673.06 ± 5.34 µg/array. Dissolution occurred within 2 min in skin, indicating user-friendly wear time. Ex vivo Franz diffusion studies showed 26% of the drug deposited into the skin, significantly higher (p = 0.0068) than the 18.3% that permeated through it. Antibacterial testing revealed strong activity against S. aureus, S. epidermidis, and C. acnes, with MIC values < 0.146 µg/mL and MBC values ranging from 9.375–18.75 µg/mL. Conclusions: The result of this research demonstrate that minocycline microneedles effectively deliver minocycline into the skin highlighting their potential as a safer and more efficient alternative for acne therapy. Full article

Background/Objectives: Epidemiological surveillance of healthcare-associated infections (HAIs) and multidrug-resistant (MDR) bacteria is a key responsibility of hospital infection control committees (HICC). Active surveillance swabs facilitate the early detection of colonized patients; helping to prevent MDR pathogen transmission in intensive care units. This study aimed to describe antimicrobial resistance profiles of bacterial isolates from clinical samples in neonatal and pediatric intensive care units. Methods: A retrospective cross-sectional study was conducted at a maternal and child hospital in Rio de Janeiro, Brazil including patients aged 0–18 years admitted to neonatal (NICU), surgical (SICU), and pediatric (PICU) intensive care units between January and December 2023. A total of 286 positive cultures were analyzed from different sample types including blood, urine, tracheal aspirates, cerebrospinal fluid (CSF), and catheter tips as well as screening swabs (nasal and rectal) for colonization surveillance. Bacterial isolates were identified and tested for antimicrobial susceptibility following BrCAST (Brazilian Committee on Antimicrobial Susceptibility Testing) guidelines. Results: Of the 286 cultures, 146 (51%) originated from the NICU, 70 (24%) from the SICU, and 70 (24%) from the PICU. Coagulase-negative staphylococci (CoNS) predominated in blood cultures, especially among neonates, while MRSA was found in all nasal swabs. Among the Gram-negative bacteria; Klebsiella pneumoniae and Pseudomonas aeruginosa were the most frequent isolates, with 30–50% resistant to third-generation cephalosporins or carbapenems. ESBL-producing organisms were found in 40% of rectal swabs. Conclusions: The predominance of CoNS in neonatal ICUs and high resistance rates among Gram-negative bacteria highlight the urgent need for continuous microbiological surveillance and antimicrobial stewardship in vulnerable pediatric populations. Full article

Disuse-induced bone loss during stall confinement and immobilization is a major concern in horses because it impairs recovery and increases susceptibility to further injury. Experimental models are needed to evaluate therapeutic options, but most available equine models rely on cast immobilization, which is technically demanding and may be associated with complications. This study aimed to assess a simpler and less restrictive model to induce a quantifiable decrease in bone density in horses. Six French Standardbred horses underwent eight weeks of stall confinement, with a wooden wedge fitted to one front foot to elevate the heels during the last four weeks. Bone density was assessed using computed tomography (CT) examinations of both forelimbs performed at the beginning (M0) and after the confinement period (M2). Serum markers of bone metabolism (CTX-I, osteocalcin, bone-specific alkaline phosphatase, and hydroxyproline) were analyzed monthly from baseline to 2 months post confinement. Statistical analysis used Wilcoxon signed-rank tests and mixed models as appropriate. Computed tomography revealed a significant decrease in bone density after confinement (p < 0.05), more pronounced distally in the wedge limb. CTX-I levels varied with physical activity. This model provides a practical and reproducible alternative to cast immobilization for inducing equine bone demineralization. Full article

This study reports the development of chitosan-based (CS) films incorporating riboflavin (RF) as a natural photosensitizer to create sustainable, light-activated antimicrobial packaging materials. The films were prepared by solvent casting, and their photochemical behavior under blue LED light (450 nm) was investigated, including RF photodegradation kinetics and structural changes in the film-forming solution analyzed by ¹H NMR spectroscopy. Mechanical, thermal, optical, and barrier properties were also characterized to assess packaging suitability. Upon illumination, CS/RF films generated reactive oxygen species, particularly singlet oxygen (¹O₂), leading to visible color changes and significant antimicrobial activity against Pseudomonas fluorescens. Bacterial growth was reduced by up to 97% after 120 min of irradiation (0.92 J cm⁻²), with efficacy observed at both room temperature and 4 °C. The incorporation of RF did not alter the films’ mechanical properties, while thermal stability was preserved, optical transparency was modulated, and excellent oxygen barrier performance was maintained, although water vapor permeability remained moderate. These findings demonstrate that CS/RF films combine functionality and sustainability, offering a promising strategy for extending food shelf life through light-activated antimicrobial action. Validation under real storage conditions is recommended to confirm their potential in diverse food systems. Full article

The effect of cross- or unidirectional rolling on the microstructure, corrosion rate, texture, and hemolysis of the Mg-0.5Zn-0.25Ga and Mg-1.5Zn-0.375Ga alloys was evaluated. After both rolling processes, the microstructure of the as-cast alloys was considerably refined due to the recrystallization process, obtaining higher grain refinement after cross-rolling. The Mg-1.5Zn-0.375Ga alloy showed a finer microstructure than the Mg-0.5Zn-0.25Mg alloy due to the effect of both the severe plastic deformation obtained after cross-rolling and the higher amount of alloying elements, which act as grain refiners. After unidirectional rolling, the texture intensity of the basal plane increases, while the cross-rolled alloys show lower texture intensity due to the activation of the pyramidal and/or prismatic slip systems. The cross-rolled alloys showed a higher corrosion rate than the unidirectionally rolled alloys due to the basal texture developed. The Mg-1.5Zn-0.375Ga alloy showed a higher corrosion rate than the Mg-0.5Zn-0.25Ga alloy since the voids formed during heat treating were not fully eliminated during rolling. The Mg-0.5Zn-0.25Ga alloy after unidirectional rolling was not hemolytic (4.7%) and showed the lowest corrosion rate (0.8 mm/y). Thus, this alloy may be an excellent candidate for use in the fabrication of biodegradable implants. Full article

Evidence-based medicine (EBM) supplies the best available data, yet clinicians still face low-value care, surrogate-driven reversals, and pseudoscientific claims. We propose Semi-Imperative Evidentialism (SIE), a normative framework that links evidential warrant to proportionate professional duties while preserving patient autonomy. Using a targeted narrative review in philosophy of science, bioethics, and clinical epidemiology, we distilled six binary attributes to classify activities as Science, Pseudoscience, or Non-science. Scientific items enter a two-tier ladder—Tier 1 (established clinical evidence) or Tier 2 (emerging or preclinical evidence)—with status re-scored as randomized trials, living meta-analyses, and post-marketing safety signals accrue. SIE maps tiers to action: Tier 1 should be offered or strongly recommended, with reasons documented if declined; Tier 2 should be discussed with explicit consent, preferably within trials or registries; Pseudoscience should be refused or discontinued with corrective education; Non-science may be acknowledged as contextual support when safe and non-substitutive. Worked examples—antiarrhythmic suppression post–myocardial infarction (CAST) and “complementary cancer cures”—illustrate earlier and more transparent course-correction. SIE provides a fallibilist bridge from evidence to duty, constraining discretion without eroding autonomy; prospective audits and cluster trials should test its impact on prescribing and consent. Full article

The food packaging industry is inclined toward biodegradable films, and jellyfish hold significant potential for exploitation due to their extraordinary collagen content. Thus, the primary objective of this research was to develop an antioxidant gelatine-based film from the blue cannonball jellyfish (Stomolophus sp. 2) (JG), using chitosan (CH) and the casting method, with glycerol (GLY) as a plasticiser to improve film flexibility. The JG obtained through alkaline, heat, and dialysis treatment exhibited high in vitro antioxidant activity. A commercial chitosan acetic acid solution (1%) was added to a JG water solution (1%) and a commercial gelatine (CG) solution (1%) was employed as a control. The film’s mass ratio was 4:1:2 (JG:CH:GLY). The physical, chemical, thermal, mechanical, and antioxidant properties of the JG-CH and CG-CH films were compared; JG-CH showed higher solubility and thermal stability than CG-CH. The colour and light transmittance were similar; however, their tensile strength and elongation differed. Furthermore, JG-CH films exhibited a higher ABTS radical-scavenging capacity compared to CG-CH films. FTIR and ¹H NMR spectra of the JG-CH films indicated excellent compatibility between the components, primarily due to hydrogen bonding. This study demonstrates that JG-CH films possess functional properties that make this material suitable for application as a biomaterial film for food. Full article

Background/Objectives: Citrus × paradisi Macfad., Rutaceae. peel is a rich source of naringin (NR), but its poor solubility and low bioavailability limit applications. This study aimed to improve NR delivery by comparing microencapsulation, liposomal microencapsulation, and buccal films containing either pure NR or grapefruit peel extract. Methods: Four spray-dried powder formulations—spray-dried NR (NS), liposomal NR (NLS), spray-dried extract (ES), and liposomal extract (ELS)—were produced using maltodextrin, β-cyclodextrin, and HPMC as wall materials. Buccal films (EP1, EP2, NP1, NP2) were prepared via solvent casting with HPMC, alginate (ALG), or polyvinyl alcohol (PVA). All samples were evaluated for solubility, moisture content, mucoadhesion, and in vitro release under simulated gastric, intestinal, and salivary conditions. Results: NR powders had the highest absolute solubility (306.42 ± 10.34 µg/mL), whereas ELS showed the lowest due to low loading. However, relative to theoretical NR content, ELS achieved the highest dissolution efficiency (55.3%), followed by NLS (42.7%), outperforming NS (5.6%) and ES (91.8%) in sustained release potential. Dual encapsulation (NLS, ELS) slowed gastric release and maintained intestinal delivery, while non-liposomal powders released rapidly. In buccal films, NP2 (NR + PVA) showed the highest release (69.97 ± 3.01 µg/mL; 40.9% efficiency) and strongest mucoadhesion (0.47 N·s). Extract-based films had lower absolute NR release but higher relative efficiency to content, likely due to co-extracted compounds enhancing wettability and matrix erosion. Conclusions: Liposomal microencapsulation improves relative dissolution efficiency and sustains intestinal release, while PVA-based buccal films enhance both release and mucoadhesion. Polymer choice and active ingredient composition are critical for optimising oral delivery of NR. These results demonstrate the potential of the proposed systems in the pharmaceutical or dietary supplement field, especially in improving the oral delivery of poorly soluble flavonoids. A graphical summary is included, visually summarising the main formulation strategies and results. Full article

Although bacterial and fungal communities play essential roles in organic matter degradation and humification during composting, their composition, interactions, abiotic compost properties, and succession patterns remain unclear. In this study, the succession of bacterial and fungal communities during algal sludge composting was explored using 16S and ITS rRNA amplicon sequencing. The compost rapidly entered the thermophilic phase (>50 °C) within the first phase. During the composting process, the diversity of bacterial and fungal communities did not show a significant response to the different composting phases. The physicochemical parameters and microbial community structures changed significantly during the thermophilic and cooling phases, particularly in the former, and gradually stabilized as the compost matured. Integrated random forest and network analyses suggested that the bacteria genera Geobacillus and Parapedobacter, along with the fungus genus Gilmaniella, could serve as potential biomarkers for different composting phases. The functional activity of the bacterial communities was obviously higher during the thermophilic phase than during the other phases, while fungal activity remained relatively high during both the thermophilic and cooling phases. Structural Equation Modeling (SEM) further indicated that bacterial communities primarily mediated nitrogen transformation and humification processes, while fungal communities mainly contributed to humification. These results cast a new light on understanding about microbial function during aerobic algal sludge composting. Full article

Food waste is a global challenge, with nearly 40% of food discarded annually, leading to economic losses, food insecurity, and environmental harm. Major factors driving spoilage include microbial contamination, enzymatic activity, oxidation, and excessive ethylene production. Active packaging offers a promising solution by extending shelf life through the selective absorption or release of specific substances. In this study, polyvinyl alcohol (PVA) films incorporating metal-organic frameworks (MOFs) were prepared via solvent casting to enhance their mechanical and barrier properties. Five MOFs (HKUST-1, MIL-88A, BASF-A520, UiO-66, and MOF-801) were embedded in the PVA matrix and analyzed for their physical, mechanical, and optical characteristics. The incorporation of TEMPO-oxidized cellulose nanofibers (CNF) improved MOF dispersion, significantly strengthening film performance. Among the formulations, PVA-CNF-MOF-801 exhibited the best performance, with a 130% increase in tensile strength, a 50% reduction in water vapor permeability, and a 168% improvement in UV protection compared with neat PVA films. Ethylene adsorption tests with climacteric fruits confirmed that CNF-containing films retained ethylene more effectively than those without CNFs, although the differences among the MOFs were minimal. These results highlight the potential of PVA-CNF-MOF composite films as sustainable active packaging materials, providing an effective strategy to reduce food waste and its environmental impact. Full article

The development of sustainable, active food packaging materials is essential for reducing plastic waste and improving food preservation. This study investigated the fabrication and characterization of bio-based films composed of sodium alginate (Na-alginate), bacterial nanocellulose (BNC), and grape seed extract (GSE) as a natural antioxidant. Films were prepared via casting solutions with 2% Na-alginate, 1% and 2% of BNC, glycerol as a plasticizer, and varying GSE concentrations (0, 0.5, 1, and 2% w/w). The films’ physicochemical properties, including thickness, mechanical strength, water vapor permeability, antimicrobial and antioxidant activity (DPPH assay), were evaluated. To assess practical applicability, blueberries were packaged in these films and stored at 4 °C for four weeks, with spoilage, weight loss, and visual quality monitored. The results demonstrated that GSE significantly enhanced the films’ antioxidant capacity, with 1% GSE achieving an optimal balance between mechanical integrity and bioactivity. Blueberries packaged in GSE-enriched films exhibited lower spoilage, reduced weight loss, and maintained better visual appearance compared to controls. These findings suggest that Na-alginate/BNC/GSE films possess potential as biodegradable active packaging materials for extending the shelf life of perishable fruits. Full article

This feasibility study evaluated a wearable sensor-based haptic feedback system designed to promote ergonomic awareness and influence posture and muscle activation patterns during a standard dental procedure. Inertial measurement units (IMUs) monitored posture by tracking back and neck angles, while four surface electromyography sensors recorded muscle activation in the lower erector spinae (LES) and upper trapezius (UT) muscles. Two IMUs with vibrotactile motors delivered real-time haptic feedback when participants maintained mechanically disadvantageous postures for extended periods during a cast metal crown preparation procedure on a manikin typodont. Data from four dental students participating in a total of 24 trials, half with and half without feedback, were analyzed via a two-way ANOVA to determine the effects of feedback and activity (e.g., inspections or drilling) on posture and muscle activation. Feedback slightly increased neck angles, but back angles remained nominally unchanged. Reduced UT activation and increased right LES activation suggests altered muscle recruitment strategies. Heatmap and RULA analyses indicated a shift toward more varied and potentially safer postural distributions during feedback trials. Postural and muscle activation data were also analyzed across four activity labels, which revealed that Drilling was consistently associated with higher ergonomic risk. Real-time haptic feedback influenced posture and muscle activation in dental students, particularly by reducing UT strain despite increased neck flexion. These findings support the integration of wearable feedback systems into preclinical training to enhance ergonomic awareness and potentially reduce the risk of developing musculoskeletal disorders, to which dentists are particularly prone. Full article

Grey cast iron brake discs with lamellar graphite (GJL) offer excellent strength and thermal conductivity but are prone to wear and dust emissions. To mitigate these issues, a multilayer coating was applied via Laser Metal Deposition (LMD), comprising a 316L stainless steel base layer and a WC-reinforced top layer. This study examines the microstructural evolution of the coatings under simulated thermomechanical and corrosive conditions using a brake shock corrosion test. Microstructural characterization was performed via Scanning Electron Microscopy (SEM) and Electron Backscatter Diffraction (EBSD), focusing on grain size, orientation, and texture before and after testing. EBSD analysis revealed significant grain coarsening, with sizes increasing from below 20 µm to 30–60 µm, and a shift toward <101> texture. Hardness measurements showed a reduction in the WC-reinforced layer from 478 HV to 432 HV and in the 316L base layer from 232 HV to 223 HV, confirming the influence of thermomechanical stress. SEM analysis revealed a transition from horizontal cracks—caused by residual stress during LMD—to vertical microcracks propagating from the substrate, activated by braking-induced loads. These findings provide insights into the microstructural response of LMD coatings under realistic service conditions and underscore the importance of grain boundary control in designing durable brake disc systems. Full article

Currently, the growing demand for sustainable hydrogen makes the oxygen evolution reaction (OER) increasingly important. To boost the performance of electrochemical cells for water electrolysis, both cathodic and anodic sides need to be optimized. Noble metal catalysts for the OER suffer from high costs and limited availability; therefore, developing efficient, low-cost alternatives is crucial. This work investigates manganese-based materials as potential noble-metal-free catalysts. Mn antimonates, Mn chlorates, and Mn bromates were synthesized using ultrasound-assisted techniques to enhance phase composition and homogeneity. Physicochemical characterizations were performed using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), together with energy-dispersive X-ray spectroscopy (EDX) and surface area analyses. All samples exhibited a low surface area and inter-particle porosity within mixed crystalline phases. Among the catalysts, Mn_7.5O₁₀Br₃, synthesized via ultrasound homogenization (30 min at 59 kHz) and calcined at 250 °C, showed the highest OER activity. Drop-casted on Fluorine-Doped Tin Oxide (FTO)-coated Ti mesh, it achieved an overpotential of 153 mV at 10 mA cm⁻², with Tafel slopes of 103 mV dec⁻¹ and 160 mV dec⁻¹ at 1, 2, and 4 mA cm⁻² and 6, 8, 10, and 11 mA cm⁻², respectively. It also demonstrated good short-term stability (1 h) in acidic media, with a strong signal-to-noise ratio. Its short-term stability is comparable to that of the benchmark IrO₂, with a potential drift of 15 mV h⁻¹ and a standard deviation of 3 mV for the best-performing electrode. The presence of multiple phases suggests room for further optimization. Overall, this study provides a practical route for designing noble metal-free Mn-based OER catalysts. Full article