Search Results (151)

Cross-laminated timber (CLT) is increasingly used in multi-story timber construction, but its combustible nature requires reliable fire protection, particularly in layered wall assemblies with concealed cavities. This study compares two medium-scale cross-laminated timber (CLT) sandwich wall assemblies exposed to radiant heat flux of 20 kW/m² for 90 min: an uncoated reference assembly and an assembly with PROMADUR^® intumescent coating applied to the CLT surfaces. Both specimens consisted of a 90 mm three-ply CLT panel encapsulated with 12.5 mm gypsum-fiber boards fixed to a wooden stud frame forming a 40 mm installation cavity. Fire-test observations were supplemented by simultaneous thermal analysis (STA), i.e., thermogravimetry (TG)/differential thermogravimetry (DTG)/differential scanning calorimetry (DSC), of uncoated and coated CLT specimens under oxidative conditions. During the applied medium-scale radiant exposure, the unexposed-face temperatures of both assemblies remained below the insulation temperature-rise limits defined in STN EN 1363-1; however, these limits were used only as a comparative benchmark and the test does not represent a formal fire-resistance classification. The coated assembly showed improved thermal protection during the early and intermediate stages of exposure, delaying a critical thermal event near the wooden stud by approximately 35 min. However, flaming combustion of the stud occurred at about 75 min and led to degradation of the intumescent char within the cavity. In contrast, the uncoated assembly reached higher early CLT surface temperatures but showed no flaming combustion during the test. STA results supported the fire-test interpretation: the coated specimen showed a 37% reduction in peak DTG rate, a higher residual mass at the end of the test, and substantially greater mass loss in the 150–280 °C range, consistent with intumescent activation and volatile release. The results indicate that, under the tested medium-scale exposure, the intumescent coating improved early and intermediate thermal protection of the CLT surface, but did not prevent late-stage cavity flaming involving the wooden stud. Therefore, the behavior of intumescent-coated CLT in partially enclosed cavities with combustible framing should be validated under replicated, standardized and larger-scale fire exposure. Full article

The aim of this study was to explore the compactibility of unidirectional staple carbon fibre laminates in comparison with their uni- and biaxial continuous fibre counterparts. Resin-preimpregnated plies were inserted into a heated compression mould at an elevated mould temperature of 110 °C. By applying stepwise loading, the correlation between consolidation pressure and fibre volume content was derived and related to fibre orientation distribution. The fibre orientation distribution is obtained from photographic image analyses of 2D ply sections of the same samples using the structure tensor approach. For commonly used autoclave prepreg pressure of 6.8 bar results indicate that lower-oriented staple carbon fibre unidirectional laminates with a fibre orientation distribution factor η₀ = 0.74 can potentially reach a maximum of 39% fibre volume fraction, while higher-oriented laminates with η₀ = 0.78 end up at 43%. An exponential extrapolation suggests that a consolidation pressure of ≥90 bar is required to achieve 60% fibre volume content with highly oriented unidirectional staple carbon fibre laminates. Full article

This study investigates the mechanical performance and blast resistance of high-performance aramid, carbon, and ultra-high molecular weight polyethylene (UHMWPE) fiber fabrics, responding to the need for lightweight and flexible materials in anti-explosion containers for aviation and critical infrastructure. The experimental methodology integrated quasi-static and dynamic tensile tests to characterize the strain-rate effect, followed by near-field air blast tests on both single-material and hybrid multi-ply fabric specimens to analyze their dynamic response, failure modes, and overpressure attenuation. Key findings revealed that carbon fabric exhibited high stiffness but was strain-rate insensitive and susceptible to brittle perforation failure, whereas aramid and UHMWPE fabrics demonstrated strain-rate sensitivity, with UHMWPE showing superior ductility and energy absorption. The hybrid multi-ply configuration (A-C-U sequence) achieved the least amount of failure, effectively utilizing the wave impedance of aramid fabric for initial shock reflection, high stiffness of carbon fabric for stress homogenization, and plasticity of UHMWPE fabric for energy dissipation. Additionally, all fabrics attenuated peak overpressure by over 80%, with enhancement observed for increased thickness. The study concludes that the strategic layering of different fabrics creates a synergistic effect, mitigating the weaknesses of individual fabrics and establishing an effective design paradigm for advanced blast-resistant structures, further enhancing the protective performance. Full article

This study developed a combined computational-experimental approach to investigate crack kinking in thick adhesively bonded Glass Fibre Reinforced Polymer (GFRP) composite joints, focusing on the adhesive joints found at wind turbine blade trailing edges. Double Cantilever Beam (DCB) tests were performed on composite joints with a 10-mm thick epoxy adhesive, representative of trailing-edge joints. Finite Element (FE) models included cross-ply GFRP composites and an adhesive layer. Subsequently, both the composite/adhesive interfaces and voids were explicitly modelled, allowing separate and combined evaluations of their effects on crack kinking. A cohesive zone model was used to capture the fracture along the composite/adhesive interfaces, while a Drucker-Prager plasticity model combined with a ductile damage model was used for the adhesive. The numerical findings indicated that crack kinking in FE simulations with explicit interfaces was primarily governed by the lower fracture resistance of the composite/adhesive interface relative to that of the bulk adhesive. Voids with a total volume fraction of approximately 1% were modelled by randomly deleting cubic 1 mm C3D8R elements in the adhesive layer to reproduce the voids typically observed in thick adhesive joints. The predicted crack paths closely matched experimental results. Simulations with voids revealed that voids above or below the adhesive midplane caused crack deflection toward the nearest interface. In models combining both features, cracks were consistently redirected toward the composite/adhesive boundary near voids, reproducing experimental observations. These results provide new insights into trailing-edge adhesive joint failure and establish a foundation for better modelling and design. Full article

Background: The PITX1 gene encodes a transcription factor that plays a crucial role in the development of the lower limbs, pelvis, and structures derived from the first branchial arch. Pathogenic variants in PITX1 are associated with a limited spectrum of rare disorders, including congenital talipes equinovarus with or without long bone anomalies and/or mirror-image polydactyly, and Liebenberg syndrome. In 2020, a novel clinical phenotype, Mandibular–Pelvic–Patellar (MPP) syndrome, resulting PITX1 missense variants, was proposed. Case presentation: We report the fourth documented case of MPP syndrome worldwide, identified in a 17-year-old female patient presenting with congenital lower limb deformities, patellar aplasia, and micrognathia. Whole-genome sequencing revealed a heterozygous PITX1 missense variant NM_002653.5: c.412A>C, p.(Lys138Gln). The clinical phenotype included knee flexion contractures and severe equinovarus and planovalgus foot deformities requiring multiple staged reconstructive surgical procedures. Conclusions: This case supports recognition of MPP syndrome as a clinically and genetically distinct PITX1-related disorder. Our findings expand the phenotypic spectrum of MPP syndrome and suggest that severe congenital foot deformities represent a consistent and clinically relevant feature of this condition. Full article

Background and Clinical Significance: Adams–Oliver syndrome type 3 (AOS3) is a rare congenital disorder typically characterised by terminal transverse limb defects and variable involvement of other organ systems. Although pathogenic variants in RBPJ are well established in AOS3, associated neurodevelopmental or psychiatric features have been only sporadically documented. Case Presentation: We describe a male patient first evaluated at the age of 10 years and subsequently re-evaluated at 14 years, with AOS3 presenting terminal limb defects together with autistic-like behaviour, cognitive difficulties, dyslexia, and recurrent depressive symptoms. Whole-exome sequencing (WES) identified a heterozygous pathogenic variant in RBPJ (c.505A>G; p.Lys169Glu), confirming the molecular diagnosis of autosomal dominant AOS3. Additional findings included a heterozygous missense variant in CACNA1A (p.Arg1678Cys), a gene linked to neurological disorders with broad phenotypic variability. Because of elevated homocysteine levels, the patient was also tested for MTHFR variants and was found to be heterozygous for C677T and A1298C. Conclusions: This case illustrates a rare combination of a validated AOS3-associated RBPJ variant, along with additional CACNA1A and MTHFR variants that may influence the patient’s neurocognitive and psychiatric characteristics. The results underscore the importance of comprehensive genetic testing in atypical AOS presentations and highlight the complexity of interpreting overlapping genetic factors. Full article

This study characterizes two novel Bacillus phages, B450T and B450C, isolated from Bacillus thuringiensis VKM B-450 via mitomycin C induction, along with their endolysin, PlyC19. Both phages, siphoviruses with 41,205 bp genomes, lysed 38% of the tested Bacillus cereus sensu lato strains, with B450C showing enhanced lytic activity due to mutations in the repressor protein. PlyC19 lysed 56% of the strains tested, including Priestia flexa, demonstrating broader efficacy. Its Amidase_2 domain and dual SH3 cell wall-binding domains enable targeted peptidoglycan hydrolysis, with optimal activity at pH 9.0 and thermal stability up to 40 °C. We propose the taxonomic designation Bquatquinnuvirus eskimopiis for these phages, with B450T and B450C representing distinct strains, based on genomic divergence in the repressor protein’s HTH_Xre domain, consistent with their turbid and clear plaque morphologies, respectively. PlyC19′s broad specificity underscores its potential as an enzybiotic against multidrug-resistant Bacillus cereus group strains in food safety and medicine. Full article

In-plane shear is the dominant deformation mode during thermoforming of fiber-reinforced composites, and accurate characterization of shear behavior is essential for reliable forming simulations. The present work investigates the shear response of a unidirectional cross-ply UHMWPE material system (DSM Dyneema^® HB210) using the picture-frame test, with emphasis on sample configuration, normalization methods, and shear rate effects. Three cruciform sample sizes were tested at 120 °C, along with a configuration in which cross-arm material was removed to isolate the gage region. Finite element analyses using LS-DYNA^® were performed to evaluate the shear rate distribution during forming and to validate the experimental characterization. To maintain a constant shear rate during testing, a decreasing crosshead speed profile was implemented in the test software. Results showed that normalizing by the full specimen area yielded consistent shear stiffness curves across sample sizes, indicating that the arm region contributes equally to the load. Samples with cross-arm material removed exhibited greater scatter than those specimens without cross-arm material removed, confirming that preparation of cross-arm removal complicates repeatability. Rate dependence was observed at room temperature but not at elevated processing temperatures, suggesting that rate-dependent shear models are unnecessary for forming simulations of this material system. These findings provide a practical methodology for shear characterization of UHMWPE cross-ply laminates suitable for thermoforming analyses. Full article

In an interlayered carbon fiber reinforced polycarbonate (CFRPC) composite constructed of nine CF plies alternating between ten PC sheets, designated [PC]₁₀[CF]₉, applying homogeneous low voltage electron beam irradiation (HLEBI) at 200 kV cathode potential, with V_c setting at a 43.2 kGy dose, to both finished sample surfaces resulted in a 47% increase in Charpy impact strength and a_uc at median fracture probability (P_f) of 0.50 over that of untreated, from 118 kJm⁻² to 173 kJm⁻². Increasingly higher V_c settings of 150, 175, and 200 kV successively increased a_uc at median-P_f of 0.50 to 128, 155, and 173 kJm⁻², respectively. Strengthening is attributed to increasing the HLEBI penetration depth, D_th, into the sample thickness. Since the [PC]₁₀[CF]₉ has an inhomogeneous structure, D_th is calculated for each ply successively into the thickness. Scanning electron microscopy (SEM) photos showed a hierarchy of fracture mechanisms from poor PC/CF adhesion in untreated; to sporadic PC adhesion with aggregated CF at 150 kV; to high consolidation of CFs by PC at 200 kV. X-ray photoelectron spectroscopy (XPS) examination of the CF surface in the fracture area showed C1s carbonate O–(C=O)–O and ester O–(C=O)–R peak generation at 289 to 292 eV to be non-existent in untreated; well-defined at 150 kV; and increased in intensity at 200 kV, after which a reduction was observed at 225 kV. Moreover, the 200 kV yielded the largest area sp³ peak at 49.5%, signifying an increase in graphitic edge planes in the CF, apparently as dangling bonds, for increased adhesion sites to PC. For O1s scan, 200 kV yielded the largest area O–(C=O)–O peak at 34%, indicating maximum PC adhesion to CF. At the higher 225 kV, increase in a_uc at P_f of 0.50 was less, to 149 kJm⁻², and XPS indicated a lower amount of O–(C=O)–O groups, apparently by excess bond severing by the higher V_c setting. Full article

We present the cloning and heterologous expression of the α-amylase gene amyBL159 from a thermophilic strain Bacillus licheniformis MGMM159, which was isolated from wastewater sediments self-heated to 70 °C. The gene was successfully cloned into the pET22b and pHT01 vectors, expressed and AmyBL159_Ec and AmyBL159_Bs recombinant α-amylases were purified from Escherichia coli BL21(DE3)pLys and Bacillus subtilis 168 strains, respectively. The AmyBL159_Ec enzyme was most active in the range of 75–95 °C, while AmyBL159_Bs showed maximum activity at temperatures from 45 to 75 °C. AmyBL159_Bs was shown to be more thermostable. Both enzymes were active over a broad pH range of 4.0–12.0. It was shown that Mn²⁺ ions enhanced the activity of both enzymes (up to 163% for AmyBL159_Ec and 142% for AmyBL159_Bs). These results highlight the importance of choosing an expression system for modulating the functional characteristics of recombinant α-amylase. The obtained AmyBL159_Ec and AmyBL159_Bs enzymes are promising for biotechnological applications under extreme conditions. The structure of the α-amylase was generated using the AlphaFold 3 web service. A structure–function analysis of this enzyme and previously studied α-amylases from B. licheniformis identified significant amino acid substitutions at positions 134(133) and 210(209) of the amino acid chain which may contribute to enhanced enzyme thermostability. Full article

On the road to developing more sustainable and cost-efficient carbon fibres (CFs), replacing the conventional polyacrylonitrile (PAN) precursor with polyethylene (PE) is a promising alternative. Yet most PE-CF studies focus on fibre properties at laboratory or pilot scale and largely overlook scalability—especially in melt-spinning, where precursor filament counts have typically been limited to 32–100, far below industrial CF tows (1000–48,000). This study addresses that gap by (i) modifying a staple-fibre melt-spinning line (MSFP) to directly produce a 10,000-filament PE precursor and (ii) demonstrating inline filament merging on an industrial yarn (IDY) plant at Institut für Textiltechnik (ITA) as a pragmatic scale-up route. Direct 10 k spinning proved technically feasible but did not meet convertibility targets owing to inhomogeneous extrusion and quench: the MSFP precursor showed 18.1 ± 2.0 µm filament diameter, 21.9 ± 3.8 cN/tex tenacity and 130.8 ± 40.8% elongation (total solid draw ratio 2.02). In contrast, the IDY route delivered a fine and uniform precursor with a 9.43 ± 0.02 µm filament diameter, 38.42 ± 0.43 cN/tex tenacity, 15.91 ± 0.76% elongation, and 15.32 ± 1.16% shrinkage at 120 °C (total solid draw ratio 4.55). After discontinuous sulfonation, TGA indicated superior cross-linking of the IDY precursor (≈15% mass loss at 400–600 °C) versus MSFP (≈18%). Inline merging doubled filament count inline and small-scale plying enabled a 6 k tow. Transferring the IDY precursor into continuous sulfonation and carbonisation yielded PE-based CF with a filament diameter < 8.5 µm, tensile strength up to 2.0 GPa, tensile modulus up to 170 GPa, and elongation at break up to 1.75%, without surface defects. The results establish a clear scale-up roadmap: prioritise homogeneous fine-filament extrusion at low throughputs, co-develop segmented quench, and use a stepwise strategy (1–2 k filaments → inline merging → ≥6 k) to enable industrially relevant, cost-effective PE-based CF production. Full article

Background/Objectives: CLIFAHDD syndrome (OMIM # 616266) is a rare neurodevelopmental disorder caused by mutations in the NALCN gene. It is characterized by hypotonia, developmental delay, and congenital contractures of the limbs and face. We report a 33-year-old Italian woman with a mild form of CLIFAHDD who exhibited early-onset language difficulties and mild intellectual disability and later developed gait and balance impairments in adulthood. Methods and Results: Whole Exome Sequencing (WES) identified a novel missense variant c.1514A>T; p.(Lys505Met) in the NALCN gene. The allele frequency of this variant is not detected (MAF = 0.0), the variant is classified as likely pathogenic according to ACMG criteria, and predicted to be probably damaging by PolyPhen-2. It affects a critical residue within the second pore-forming domain of the NALCN channel, potentially altering lipid interactions and channel regulation. Sanger sequencing and segregation analysis confirmed the variant to be heterozygous and de novo. Conclusions: The patient’s milder symptoms and later onset, compared to severe pediatric cases, suggest that the clinical spectrum of CLIFAHDD syndrome may be broader than previously recognized. These findings underscore the potential influence of mutation location on disease presentation and severity. Full article

This work provides a comparison of two commercial carbon fiber reinforced plastic (CFRP) materials: HexPly^® M18 1/G939 and RTM6/G939. Differences due to the additional thermoplastic in one CFRP are investigated for the two otherwise nearly identical, aromatic epoxy-based composites with respect to thermal degradation. The scenario chosen for testing is based on real incidents of repeated overheating by hot gases between roughly 200 and 320 °C, leading to moderate thermal damage. A special test setup is designed to continuously and alternately load CFRP with hot air in a rapid change. Post-mortem analysis is performed by mass loss, ultrasonic, and mechanical testing. Polymer degradation is analyzed by infrared spectroscopy. Even if the temperature-resistant thermoplastic polyetherimide (PEI) in the M18-1 matrix is enriched between the plies and a compensation of thermal strain during rapid temperature changes is expected, only a weak improvement is observed for residual strength in the presence of PEI, for continuous as well as alternating thermal loading. Thermally induced delaminations are even more pronounced in M18-1/G939. Deep insight is gained into degradation after repeated overheating of CFRP within the chosen scenario. Multivariate data analyses based on infrared spectroscopy allow for the determination of thermal history and residual strength, valuable for failure analysis. Full article

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is an autosomal recessive disorder of fatty acid oxidation that can have life-threatening consequences if not promptly treated. Early diagnosis by means of newborn screening (NBS) has the potential to reduce morbidity and mortality. This study investigates the incidence and molecular characteristics of MCADD in Italy over a five-year period within the framework of the expanded NBS program. Between January 2019 and December 2023, a total of 1,976,473 newborns were screened. Ninety unrelated neonates were diagnosed with MCADD, providing an estimated incidence of 1/21,960 live births (95% CI: 1:17,780–1:27,200), comparable to rates reported in other Mediterranean populations. Molecular analysis identified c.985A>G (p.Lys329Glu) as the most frequent pathogenic ACADM gene variant, observed in 56 patients (63%), including eighteen patients (20%) who were homozygous and thirty-eight (43%) who were compound heterozygotes for this variant. To our knowledge, this study represents the first comprehensive investigation to document the high prevalence of MCADD among the Italian population. Full article

Pathogenic variants in ODAD4 are an ultra-rare cause of primary ciliary dyskinesia (PCD). Previously reported cases display classic disease phenotypes, including chronic oto-sino-pulmonary disease and development of bronchiectasis by adulthood. We report five individuals with PCD harboring biallelic ODAD4 variants (median age 14, range 3–41 years). Participants underwent standardized PCD diagnostic evaluations. Three individuals shared the novel homozygous ODAD4 genotype [NM_031421.5: c.245delA, p.(Lys82Argfs*29)], and genealogy analysis highly suggests a founder effect in French-Canadians from two regions of Quebec. All five participants had normal pulmonary function values. Two Quebec participants lacked radiographic pneumonias or bronchiectasis (ages 14 and 38 years) despite life-long suppurative respiratory symptoms, low nasal nitric oxide levels, and outer dynein arm defects on electron microscopy. Reverse transcription polymerase chain reaction of the c.245delA variant showed abnormal splicing with in-frame skipping of exon 2, allowing expression of a mildly shortened mRNA product. However, functional analysis showed overall static cilia, absence of ODAD4 protein on Western blot, and absence of in vivo mucociliary clearance. The reason for a milder pulmonary phenotype with the c.245delA variant in ODAD4 remains unclear, but regional screening for this variant in Quebec may identify more cases and enhance understanding of this mild form of PCD. Full article