Search Results (994)

Divinylisoprene rubber, a copolymer of butadiene and isoprene, is used as raw material for rubber technical products, combining isoprene rubber’s elasticity and butadiene rubber’s wear resistance. These properties depend quantitatively on the copolymer composition, which depends on the kinetics of its synthesis. This work aims to theoretically describe how the monomer mixture composition in the butadiene–isoprene copolymerization affects the activity of the TiCl₄–Al(i-C₄H₉)₃ catalytic system (expressed by active sites concentration) via kinetic modeling. This enables development of a reliable kinetic model for divinylisoprene rubber synthesis, predicting reaction rate, molecular weight, and composition, applicable to reactor design and process intensification. Active sites concentrations were calculated from experimental copolymerization rates and known chain propagation constants for various monomer compositions. Kinetic equations for active sites formation were based on mass-action law and Langmuir monomolecular adsorption theory. An analytical equation relating active sites concentration to monomer composition was derived, analyzed, and optimized with experimental data. The results show that monomer composition’s influence on active sites concentration is well described by a two-step kinetic model (physical adsorption followed by Ti–C bond formation), accounting for competitive adsorption: isoprene adsorbs more readily, while butadiene forms more stable active sites. Full article

Trauma-informed care (TIC) is an increasingly implemented approach in human services, but little research documents implementation within veterinary services. This study explored emotional experiences of veterinary clients and the perceived emotions/behaviors of their pets, studied experiences of TIC, and ascertained the extent to which experiences of TIC predicted client outcomes. Clients (N = 274) were surveyed about their experiences of veterinary care. Clients documented positive and negative emotional experiences, with negative emotions associated with more serious presenting issues. TIC was experienced during veterinary visits. Principal component analyses found that TIC fell into the following five factors: (1) transparent and client-centered communication; (2) client supports and strengths; (3) emotional safety and empowerment; (4) physical safety and comfort; (5) informed consent. Hierarchical regressions revealed that, after controlling for reason for the visit, client-reported emotions and pet emotions/behaviors, 53.9% and 56.3% of the variance in client satisfaction and client disappointment was accounted for by TIC practices, respectively. The results show that although the outcomes for pets receiving veterinary care might not always be positive, which can lead to negative emotional experiences for clients, these can be ameliorated and lead to positive client outcomes through utilizing TIC. Full article

Background/Objectives: The objective of this study was to validate a new parent-reported scale for tracking Pediatric Acute-onset Neuropsychiatric Syndrome (PANS). PANS is a condition characterized by a sudden and severe onset of neuropsychiatric symptoms. To meet diagnostic criteria, an individual must present with either obsessive–compulsive disorder (OCD) or severely restricted food intake, accompanied by at least two additional cognitive, behavioral, or emotional symptoms. These may include anxiety, emotional instability, depression, irritability, aggression, oppositional behaviors, developmental or behavioral regression, a decline in academic skills such as handwriting or math, sensory abnormalities, frequent urination, and enuresis. The onset of symptoms is usually triggered by an infection or an abnormal immune/inflammatory response. Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) is a subtype of PANS specifically linked to strep infections. Methods: We developed a 101-item PANS/PANDAS and Related Inflammatory Brain Disorders Treatment Evaluation Checklist (PTEC) designed to assess changes to a patient’s symptoms over time along 10 subscales: Behavior/Mood, OCD, Anxiety, Food intake, Tics, Cognitive/Developmental, Sensory, Other, Sleep, and Health. The psychometric quality of PTEC was tested with 225 participants. Results: The internal reliability of the PTEC was excellent (Cronbach’s alpha = 0.96). PTEC exhibited adequate test–retest reliability (r = 0.6) and excellent construct validity, supported by a strong correlation with the Health subscale of the Autism Treatment Evaluation Checklist (r = 0.8). Conclusions: We hope that PTEC will assist parents and clinicians in the monitoring and treatment of PANS. The PTEC questionnaire is freely available at neuroimmune.org/PTEC. Full article

High-titanium steel contains an elevated titanium content, which promotes the formation of abundant non-metallic inclusions in molten steel at high temperatures, including titanium oxides, sulfides, and nitrides. These inclusions adversely affect continuous casting operations and generate substantial internal/surface defects in cast slabs, ultimately compromising product performance and service reliability. Therefore, stringent control over the size, distribution, and population density of inclusions is imperative during the smelting of high-titanium steel to minimize their detrimental effects. In this paper, samples of high titanium steel (0.4% Ti, 0.004% N) casting billets were analyzed by industrial test sampling and full section comparative analysis of the samples at the center and quarter position. Using the Particle X inclusions, as well as automatic scanning and analyzing equipment, the number, size, location distribution, type and morphology of inclusions in different positions were systematically and comprehensively investigated. The results revealed that the primary inclusions in the steel consisted of TiN, TiS, TiC and their composite forms. TiN inclusions exhibited a size range of 1–5 µm on the slab surface, while larger particles of 2–10 μm were predominantly observed in the interior regions. Large-sized TiN inclusions (5–10 μm) are particularly detrimental, and this problematic type of inclusion predominantly concentrates in the interior regions of the steel slab. A gradual decrease in TiN inclusion number density was identified from the surface toward the core of the slab. Thermodynamic and kinetic calculations incorporating solute segregation effects demonstrated that TiN precipitates primarily in the liquid phase. The computational results showed excellent agreement with experimental data regarding the relationship between TiN size and solidification rate under different cooling conditions, confirming that increased cooling rates lead to reduced TiN particle sizes. Both enhanced cooling rates and reduced titanium content were found to effectively delay TiN precipitation, thereby suppressing the formation of large-sized TiN inclusions in high-titanium steels. Full article

TiO₂ was synthesized via the sol–gel method and employed as a support material for the deposition of CdS nanofibers using two novel techniques: impregnation and photodeposition. XRD characterization shows that crystallite size decreases when CdS is incorporated into TiO₂. UV-Vis spectroscopy showed that the bandgap of the CdS/TiO₂ heterostructured nanocomposites decreases compared to the raw TiO₂ support, making them very appropriate for photocatalytic applications in the visible region. The photocatalysts were tested for hydrogen production in methanol–water solutions under visible light conditions. It was observed that the TiC20 photocatalyst prepared by the impregnation method improved the photocatalytic activity compared with photodeposition technique (TiC20FD), achieving a maximum hydrogen production of 570.5 µmol H₂ ${\mathrm{g}}_{\mathrm{c}\mathrm{a}\mathrm{t}}^{-1}$ h⁻¹, while the latter attained 383.4 µmol H₂ ${\mathrm{g}}_{\mathrm{c}\mathrm{a}\mathrm{t}}^{-1}$ h⁻¹. Full article

The titanium matrix composites (TMCs) fabricated via Directed Energy Deposition (DED) effectively overcome the issue of coarse columnar grains typically observed in additively manufactured titanium alloys. In this study, systematic annealing heat treatments were applied to in situ (TiB + TiC)/Ti-6Al-4V composites to refine the microstructure and tailor mechanical properties. The results reveal that the plate-like α phase in the as-deposited composites gradually transforms into an equiaxed morphology with increasing annealing temperature and holding time. Notably, when the annealing temperature exceeds 1000 °C, significant coarsening of the TiC phase is observed, while the TiB phase remains morphologically stable. Annealing promotes decomposition of acicular martensite and stress relaxation, leading to a reduction in hardness compared to the as-deposited state. However, the reticulated distribution of the TiB and TiC reinforcement phases contributes to enhanced tensile performance. Specifically, the as-deposited composite achieves a tensile strength of 1109 MPa in the XOY direction, representing a 21.6% improvement over the as-cast counterpart, while maintaining a ductility of 2.47%. These findings demonstrate that post-deposition annealing is an effective strategy to regulate microstructure and achieve a desirable balance between strength and ductility in DED-fabricated titanium matrix composites. Full article

In this investigation, TiB₂–TiC composite powders, synthesized via the boron/carbon thermal reduction process, were employed as precursor materials. SiC, serving as the tertiary constituent, was incorporated to fabricate TiB₂–TiC–SiC composite ceramics utilizing spark plasma sintering technology. The present study initially elucidates the densification mechanisms and investigates the influence of sintering temperature on the densification behavior, microstructural evolution, and mechanical properties of the resultant ceramics. The experimental findings reveal that the sintering process of TiB₂–TiC–SiC ceramics exhibits characteristics consistent with solid-phase sintering. As the sintering temperature escalates, both the relative density and mechanical properties of the ceramics initially improve, reaching a maximum at an optimal sintering temperature of 1900 °C, before subsequently declining. Microstructural examinations conducted at this optimal temperature indicate a homogeneous distribution of the two primary phases, with no evidence of excessive grain growth. Furthermore, this research explores the effects of SiC addition on the mechanical performance and oxidation resistance of TiB₂–TiC–SiC composite ceramics. The results demonstrate that the incorporation of SiC effectively suppresses grain growth and promotes the formation of rod-like TiB₂ microstructures, thereby enhancing the mechanical attributes of the ceramics. Additionally, the addition of SiC significantly improves the oxidation resistance of the composite ceramics compared to their TiB₂–TiC binary counterparts Full article

The laser cladding (LC) of titanium matrix composite coatings (TMCCs) on titanium components not only effectively enhances the wear resistance, fatigue resistance, corrosion resistance, and biocompatibility of titanium and its alloys, but also circumvents the incompatibility and low bonding strength issues associated with other metallic composite coatings. While the incorporation of ceramic particles is a critical strategy for improving the coating performance, the limited interfacial bonding strength between ceramic particles and the matrix has historically constrained its advancement. To further elevate its performance and meet the demands of components operating in harsh environments, researchers worldwide have employed LC to synthesize in situ hard ceramic reinforcements such as TiC, TiB, TiN, and others within TMCCs on titanium substrates. This approach successfully addresses the aforementioned challenges, achieving coatings that combine a high interfacial bonding strength with superior mechanical properties. This paper provides a comprehensive review of the processing techniques, phase composition, microstructure, and mechanical properties of in situ-synthesized ceramic-reinforced TMCCs via LC on titanium components, with a focused summary of their strengthening mechanisms. Furthermore, it critically discusses the challenges and future prospects for advancing this technology. Full article

Background/Objectives: A direct link between sensory processing disorder (SPD) and strabismus has not been systematically investigated, though prior studies suggest sensory modulation may influence visual behaviors. Traditional approaches view strabismus through a binary lens—either normal or pathological motor deviation. This report presents a proof-of-concept case suggesting strabismus may represent a neurobehavioral manifestation of sensory processing imbalance, rooted within the broader framework of SPD. Methods: We report a pediatric case marked by episodic monocular eye closure triggered by environmental stimuli, without identifiable ophthalmologic or neurologic pathology. The child’s symptoms were most consistent with sensory over-responsivity (SOR), a subtype of SPD, manifesting as stimulus-bound monocular eye closure and secondary self-regulatory behaviors. Results: We propose the Fusion Dysregulation Hypothesis, suggesting that exotropia and esotropia represent opposing outcomes along a continuum of sensory connectivity: exotropia arising from neural underwiring (hyporesponsivity and fusion instability), and esotropia from overwiring (hyperresponsivity and excessive fusion drive). Our case, marked by sensory hyperresponsivity, showed frequent monocular eye closure that briefly disrupted but did not impair fusion. This suggests an “overwired” binocular system maintaining single vision despite sensory triggers. In early-onset esotropia, such overconnectivity may become maladaptive, leading to sustained convergence. Conversely, autism spectrum disorder, typically associated with hypoconnectivity, may predispose to exotropia through reduced fusion maintenance. Conclusions: These findings highlight the need for interdisciplinary evaluation. We advocate for structured sensory profiling in children presenting with strabismus and, conversely, for ophthalmologic assessment in those diagnosed with SPD. While our findings remain preliminary, they support a bidirectional screening approach and suggest that sensory modulation may play a previously under-recognized role in the spectrum of pediatric strabismus presentations. Full article

Powder injection molding (PIM) has been used to produce nearly net-shaped samples of tungsten-based alloys. These alloys have been previously shown to have favorable characteristics when compared with standard ITER-grade tungsten. Six different alloys were produced with this method: W-1TiC, W-2Y₂O₃, W-3Re-1TiC, W-3Re-2Y₂O₃, W-1HfC and W-1La₂O₃-1TiC. These were tested alongside ITER-grade tungsten in the PSI-2 linear plasma device under ITER-relevant plasma and heat loads to assess their suitability for use in a fusion reactor. All materials showed good behavior when exposed to the lower pulse number tests (≤1000 ELM-like pulses), although standard tungsten performed slightly better, with no observable difference in surface roughness. High-power shots, namely one laser pulse of 1.6 GWm⁻², revealed that samples containing yttria are more prone to melting and droplet ejection. After high pulse number tests (10,000 and 100,000 pulses), with and without plasma, the reference tungsten showed the most cracking and highest surface roughness of all materials, while the PIM samples seemed to have a higher resistance to cracking. This can be attributed to the higher ductility of these alloys, particularly those containing rhenium. This means that tungsten-based alloys, whether produced via PIM or other methods, could potentially be used in certain areas of a fusion reactor. Full article

Background/Objectives: Depression impairs the quality of life in older adults and represents a significant public health issue. Cognitive reserve may act as a protective factor against depressive symptoms in older adults. Additionally, interaction with pets may serve as another potential protective factor against these symptoms. Thus, this study aimed to evaluate whether higher cognitive reserve could predict a reduction in depressive symptoms in older adults and to investigate the moderating role of pet companionship in this relationship. Methods: The following instruments were used: a Sociodemographic Data Sheet, the Modified Telephone Interview for Cognitive Status (TICS-M), the Cognitive Reserve Index Questionnaire (CRIq), and the Geriatric Depression Scale (GDS-15). Data were collected via video calls through WhatsApp and analyzed using a moderation analysis with PROCESS for SPSS. Results: The final sample consisted of 215 older adults with a mean age of 69.13 years (SD = 6.89). Among the participants, 53% owned pets and 47% did not. The overall model revealed a significant association between the predictor variables and the outcome (F(3, 211) = 4.24, p < 0.01). For the group without pets, the effect was not significant (β = −0.1082, p = 0.2916), but for the group with pets, the effect was substantial and negative on the GDS (β = −0.1936, p < 0.05). Conclusions: We concluded that the relationship between cognitive reserve and depressive symptoms is moderated by the presence of pets in individuals’ lives. These findings highlight the role of pets in protecting against depressive symptoms in older adults. Future studies should explore this relationship with more diverse samples. Full article

Light curve analysis of W UMa-type contact binary systems using MCMC or MC methods can be time-consuming, primarily because the repeated generation of synthetic light curves tends to be relatively slow during the fitting process. Although various approaches have been proposed to address this issue, their implementation is often challenging due to complexity or uncertain performance. In this study, we introduce the BSN application, whose name is taken from the BSN project. The application is designed for analyzing contact binary system light curves, supporting photometric data, and employing an MCMC algorithm for efficient parameter estimation. The BSN application generates synthetic light curves more than 40 times faster than PHOEBE during the MCMC fitting process. The BSN application enhances light curve analysis with an expanded feature set and a more intuitive interface while maintaining compliance with established scientific standards. In addition, we present the first light curve analyses of four contact binary systems based on the TESS data, utilizing the BSN application version 1.0. We also conducted a light curve analysis using the PHOEBE Python code and compared the resulting outputs. Two of the target systems exhibited asymmetries in the maxima of their light curves, which were appropriately modeled by introducing a cold starspot on one of the components. The estimated mass ratios of these total-eclipse systems place them within the category of low mass ratio contact binary stars. The estimation of the absolute parameters for the selected systems was carried out using the $P-a$ empirical relationship. Based on the effective temperatures and masses of the components, three of the target systems were classified as A-subtype, while TIC 434222993 was identified as a W-subtype system. Full article

Composite electrodeposited coatings hold significant potential for marine and aerospace applications due to their synergistic corrosion resistance and wear durability, yet nanoparticle agglomeration and interfacial incompatibility persistently undermine their performance. Conventional dispersion techniques—mechanical agitation, surfactants, or high-energy methods—fail to resolve these issues, often introducing residual stresses, organic impurities, or thermal damage to substrates. This study addresses these challenges through a novel thermal-assisted alkaline etching (TAE) protocol that synergistically removes surface oxides and enhances colloidal stability in β-SiC nanoparticles. By combining NaOH-based etching with low-temperature calcination (250 °C), the method achieves oxide-free SiC surfaces with elevated hydrophilicity and a ζ-potential of −25 mV, enabling submicron clustering (300 nm) without surfactants. Electrodeposited Co/SiC coatings incorporating TAE-SiC exhibited current-modulated reinforcement, achieving optimal SiC incorporation (5.9 at% Si) at 8 A/dm² through electrophoretic–hydraulic synergy, along with uniform cross-sectional distribution validated by SEM. Tribological assessments revealed shorter wear tracks in TAE-SiC-enhanced coatings compared to their untreated counterparts, suggesting enhanced interfacial coherence despite a comparable mass loss. Demonstrating scalability through cost-effective aqueous-phase chemistry, this methodology provides a generalized framework applicable to other ceramic-reinforced systems (e.g., Al₂O₃ and TiC), offering transformative potential for next-generation protective coatings in harsh operational environments. Full article

The carbonate content serves as a fundamental proxy in lacustrine sediments for reconstructing palaeoclimate and environmental changes. Although multiple analytical techniques exist for its quantification, systematic comparisons between different methodologies and the precise identification of carbonate mineralogy are still needed. In this study, a 1020 cm continuous sediment core (YZH-1) from Lake Yangzong in Yunnan Province was employed. Initially, the semi-quantitative calcium (Ca) concentration was obtained via X-ray fluorescence (XRF) core scanning. Subsequently, the total inorganic carbon (TIC) content was determined using both the loss on ignition (LOI) and gasometric (GM) methods to evaluate methodological discrepancies and potential biases. Furthermore, a quantitative regression model was developed to estimate carbonate abundance based on the relationship between XRF-derived Ca data and the analytically determined carbonate content. A comparative analysis revealed a strong positive correlation (r = 0.97) between LOI and GM measurements, though LOI-derived values are systematically elevated by 2.6% on average. This overestimation likely stems from the thermal decomposition of non-carbonate minerals during LOI analysis. Conversely, GM measurements exhibit a ~5% underestimation relative to certified reference materials, attributable to instrumental limitations such as gas leakage. Strong covariation (r = 0.92) between XRF-Ca intensities and the TIC content indicates that carbonate minerals in Lake Yangzong sediments predominantly consist of calcite. A transfer function was established to convert XRF-Ca scanning data into absolute Ca concentrations, leveraging the robust Ca-TIC relationship. The proposed quantification model demonstrates high reliability when applied to standardized XRF-Ca datasets, offering a practical tool for paleolimnological studies in similar geological settings. Full article

Cannabinoid receptor 1 (CB₁) signalling is critical for weight gain and for milk intake in newborn pups. This is important as in humans, low birth weight increases the risk for attention-deficit hyperactivity disorder (ADHD). Moreover, some children with ADHD also have Tourette syndrome (TS). However, it remains unclear if insufficient CB₁ receptor signalling may promote ADHD/TS-like behaviours. Here, ADHD/TS-like behaviours were studied from postnatal to adulthood by exposing postnatal wild-type CB₁ and Cannabinoid receptor 2 (CB₂) knockout mouse pups to SR141716A (rimonabant), a CB₁ receptor antagonist/inverse agonist. Postnatal disruption of the cannabinoid system by SR141716A induced vocal-like tics and learning deficits in male mice, accompanied by excessive vocalisation, hyperactivity, motor-like tics and/or high-risk behaviour in adults. In CB₁ knockouts, rearing and risky behaviours increased in females. In CB₂ knockouts, vocal-like tics did not develop, and males were hyperactive with learning deficits. Importantly, females were hyperactive but showed no vocal-like tics. The appearance of vocal-like tics depends on disrupted CB₁ receptor signalling and on functional CB₂ receptors after birth. Inhibition of CB₁ receptor signalling together with CB₂ receptor stimulation underlie ADHD/TS-like behaviours in males. This study suggests that the ADHD/TS phenotype may be a single clinical entity resulting from incorrect cannabinoid signalling after birth. Full article