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关键词： Type 1 diabetes   Bone health   Pediatrics  

摘要：

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  Youth with T1D have lower HAZ-adjusted TBLH BMD z-scores compared with normative pediatric reference data.
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  BMI z-scores, and 25(OH)D levels are key factors associated with HAZ-adjusted BMD z-scores in youth with T1D.
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  Vitamin D deficiency is linked to lower HAZ-adjusted BMD z-scores in this population.
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  Maintaining a healthy weight and adequate vitamin D may support bone health in youth with T1D.

关键词： (Ta-W)1-xCrxcoatings   Cr alloying   Mechanical properties   Microstructure   Phase evolution  

摘要： Mechanical properties of (Ta-W)_1-xCr_x coatings were successfully enhanced by Cr-driven phase and microstructure optimization. The (Ta-W)_1-xCr_x coatings exhibited a progressive phase evolution with increasing Cr content, changing from a single body-centered cubic phase to a dual-phase region, then transitioning to a fully amorphous region, followed by an amorphous matrix coexisting with a nanocrystalline region and, finally, an amorphous matrix coexisting with surface crystallization. Systematic phase stability analysis indicates that such evolution is driven by Cr-mediated atomic-size mismatch, which drives severe lattice distortion and synergizes with entropy/enthalpy effects to suppress crystallization during deposition. The hardness of (Ta-W)_1-xCr_x coatings increased with Cr content and reached the maximum value (20.3 GPa) at 56.2 at.% Cr, which can be attributed to the combined effect of solid-solution strengthening, amorphous strengthening, and grain-refinement strengthening. The (Ta-W)_1-xCr_x coatings achieved maximum H/E and H³/E² of 0.084 and 0.132, respectively, exceeding those reported for most refractory-metal and multi-principal-element alloy coatings.

关键词： Goethite   α-(Fe,Al)OOH   Aluminum substitution   Weak ferromagnetism   Antiferromagnetism  

摘要： Goethite (α-FeOOH) is an antiferromagnetic iron oxyhydroxide that frequently exhibits a weak ferromagnetic component, a behavior widely discussed in the literature but still not completely understood at the microscopic level. In Al-substituted goethites, this magnetic response becomes even more complex due to the combined effects of magnetic dilution and local structural perturbations introduced by the substitution of Fe³⁺ with non-magnetic Al³⁺ ions. In this study, we investigated the magnetic behavior of synthetic goethites with different Al contents through magnetization measurements as a function of the field and temperature, in combination with compositional and structural characterization using Wavelength Dispersive X-ray Fluorescence (WDXRF) and Raman spectroscopy. The results reveal a progressive reduction in the Néel temperature with increasing Al concentration, accompanied by pronounced magnetic irreversibility at low fields and a decoupling between the temperature evolution of the coercive field and the remanent magnetization. In contrast to pure goethite, where these quantities evolve more coherently, the Al-substituted samples show a faster suppression of remanence, while coercivity remains finite and close to the magnetic transition temperature, indicating distinct mechanisms governing magnetization reversal and magnetic remanence. When considered together with previous spectroscopic results reported for the same samples, these findings support the scenario of intrinsic magnetic inhomogeneity. The magnetic behavior is consistent with the diamagnetic-island model, in which Al incorporation leads to the formation of magnetically weakened regions within the goethite matrix, giving rise to local perturbations of antiferromagnetic order. The present results provide new magnetic evidence supporting the model previously proposed for Al-substituted goethites, while remaining compatible with literature models that attribute weak ferromagne

摘要： Solvent-dependent luminescence and excited-state relaxation of 1-aminoanthraquinone (1-AAQ) were investigated in methanol and n-pentane by combining steady-state absorption/fluorescence spectroscopy, femtosecond transient absorption (TA) spectroscopy, TD-DFT calculations, torsion-dependent state analysis, and an explicit microsolvated 1-AAQ···CH₃OH model. The central finding is that methanol does not merely act as a polar medium, but accelerates excited-state relaxation through carbonyl-centered hydrogen-bond-assisted stabilization of the anthraquinone acceptor framework. Experimentally, methanol induces bathochromic shifts of both absorption and fluorescence maxima from approximately 460/560 nm in n-pentane to 477/590 nm in methanol, together with a larger Stokes shift, consistent with increased stabilization of the relaxed emissive state. TD-DFT calculations reproduce this trend and show that the optically allowed S₀→S₁ transition is lowered in methanol from 2.6098 eV to 2.4945 eV, with a slightly increased oscillator strength. Frontier-orbital and dipole-moment analyses reveal pronounced donor-to-acceptor charge redistribution from the amino group to the anthraquinone core, accompanied by amino-group twisting, indicating an intramolecular charge-transfer/twisted intramolecular charge-transfer (ICT/TICT)-like relaxation coordinate. The optimized 1-AAQ···CH₃OH cluster further shows a representative C=O···H–OCH₃ hydrogen bond motif, with an H···O=C distance of approximately 1.8 Å and an O···O donor–acceptor distance of approximately 2.8 Å; the associated C=O elongation and O–H/C=O vibrational red shifts support local perturbation and stabilization of the carbonyl acceptor site. Femtosecond TA spectra reveal broader excited-state absorption (ESA)/stimulated emission (SE) overlap and clear early-time spectral evolution in methanol, whereas n-pentane exhibits narrower, more localized transient features. Sequential

关键词： Autoimmune thyroid disorder   Bangladeshi patients   Disease susceptibility   Genetic association with HT   Genetic polymorphisms   Hashimoto's thyroiditis   IL1Brs1143634   PTGS2rs2745557  

摘要： Hashimoto's thyroiditis (HT) is a chronic autoimmune thyroid disorder characterized by lymphocytic infiltration and progressive thyroid dysfunction. Genetic factors, particularly inflammation-related polymorphisms, play a critical role in disease susceptibility and progression. This study investigated the demographic, clinical, biochemical, and genetic characteristics of HT patients in a Bangladeshi population, focusing on PTGS2 rs2745557 (encoding COX-2) and IL1B rs1143634 (encoding IL-1β) polymorphisms.

关键词： DEHP   Environmental Toxicology   Male Infertility   Male Reproductive Health  

摘要： Di-(2-ethylhexyl) phthalate (DEHP) and its active metabolite mono-(2-ethylhexyl) phthalate (MEHP) are environmental endocrine disruptors associated with male reproductive toxicity, but the underlying mechanisms remain unclear. This study investigated whether N6-methyladenosine (m6A) modification is involved in DEHP/MEHP-induced reproductive damage using both an immature rat DEHP exposure model in vivo and MEHP-treated GC-1 cells in vitro. In vivo, DEHP exposure induced obvious testicular injury in immature rats, including structural disorder of seminiferous tubules and decreased seminiferous epithelium height and tubule diameter. In vitro, MEHP increased global m6A levels, altered cell cycle distribution, and disrupted the expression of self-renewal- and differentiation-related markers in GC-1 cells. MeRIP-seq further revealed increased m6A peaks and enrichment of cell cycle-related pathways after MEHP exposure. Among the examined m6A regulators, YTHDF1 showed significant upregulation after MEHP treatment. Moreover, YTHDF1 knockdown reversed the abnormal expression of self-renewal- and differentiation-related proteins induced by MEHP. These findings suggest that dysregulated m6A modification, potentially involving YTHDF1, participates in DEHP/MEHP-induced male reproductive damage.

关键词： Zeolite   Membrane   Separation   n-Alkane   Aviation fuel  

摘要： The removal of linear hydrocarbons from hydrocarbon mixtures using a silicalite-1 membrane has been demonstrated. The molecular sieving property of silicalite-1 membrane was evaluated by vapor permeation tests in unary systems using 15 hydrocarbons of various molecular sizes. The results of the unary permeation tests suggest that the permeance of each hydrocarbon strongly depends on its critical dimension. The hydrocarbon permeance through the silicalite-1 membrane can be explained by the ratio of the cross-sectional area of the molecules, calculated from their critical dimensions, to that of the micropore. Consequently, the silicalite-1 membrane exhibited superior n-alkane selectivity owing to the molecular sieving effect. For practical light oil, including C₈-C₂₈ hydrocarbons with 26 wt% linear hydrocarbons, the silicalite-1 membrane successfully removed linear hydrocarbons with a flux of 0.662 L m⁻² h⁻¹ and a purity of 94 wt% at 673 K. The membrane performance was maintained even after >200 h of intermittent use for various hydrocarbon separation.

关键词： Chlorine dioxide (ClO(2))   Human astrovirus (HAstV)   Immunofluorescence (IF) assay   Oyster   Peracetic acid (PAA)   Ultraviolet-C (UV-C)   Viral inactivation  

摘要： This study evaluated the antiviral efficacy of chlorine dioxide (ClO₂) and peracetic acid (PAA) as chemical disinfectants, and UV-C irradiation as a physical treatment, against HAstV-1, applied individually or sequentially on three relevant matrices: oysters, stainless steel (SS; food-contact surface), and low-density polyethylene (LDPE; packaging surface). Infectious viral titers were quantified using a modified immunofluorescence (IF) assay, which was optimized for oyster matrices in this study by adjusting virus adsorption time, antibody conditions, and buffer composition to enhance reproducibility and signal clarity. Treatment with ClO₂ (200 ppm, 5 min) and PAA (200 ppm, 1 min) resulted in greater reductions (>2 log₁₀ FFU/mL) on oyster tissues compared to UV-C irradiation (1800 mJ/cm²; 1.8 log₁₀ FFU/mL). HAstV-1 levels dropped below the detection limit when treated with ≥700 ppm ClO₂ and ≥1500 ppm PAA on SS and ≥300 ppm ClO₂ and ≥900 ppm PAA on LDPE, respectively. UV-C treatment at 3600 mJ/cm² achieved reductions of 1.37 and 1.63 log₁₀ FFU/mL on SS and LDPE, respectively. Sequential treatments combining ClO₂ (50 ppm) or PAA (150 ppm) with subsequent UV-C irradiation (600 mJ/cm²) significantly enhanced HAstV-1 inactivation on oyster surfaces, yielding additional reductions of 0.96 and 0.57 log₁₀ FFU/mL, respectively. Texture and color analyses indicated slight decreases in hardness and chewiness (p < 0.05); however, no significant differences were observed in elasticity or color parameters (p > 0.05). The modified IF assay demonstrated improved reproducibility and signal clarity and was successfully applied for detecting infectious HAstV-1 in oyster matrices.

关键词： 1-Hydroxypyrene glucuronide   3D printing   3D-printed electrochemical biosensor   Competitive immunoassay   Wood smoke biomarker  

摘要： The polycyclic aromatic hydrocarbons (PAHs) from wood smoke are harmful to human health. In this study, an innovative 3D-printed flexible electrochemical biosensor was developed for the detection of 1-hydroxypyrene glucuronide (1-OHPG), a major metabolite of PAHs in human urine. The proposed biosensor integrated competitive immunoassay and electrochemical analysis to enhance detection specificity and sensitivity. Three 3D printing techniques, fused deposition modeling (FDM), stereolithography (SLA), and direct ink writing (DIW), were synergistically combined to improve performance and reduce fabrication costs of the biosensor. Polylactic acid/carbon black-based electrodes were produced via FDM printing and activated through chemical treatment using N,N-dimethylformamide, 0.5 M H₂SO₄, 1 M NaOH followed by electrochemical treatment at 2.5 V for 100 s in 0.1 M PBS solution to enhance their electrochemical activity. The flexible biosensor substrate was fabricated using SLA printing to enable integration with the electrodes. Using the DIW method, Ag/AgCl conductive paste was printed to serve as the reference electrode. The hapten-bovine serum albumin conjugate was uniformly immobilized on the working electrode via DIW printing to enhance the sensitivity and selectivity of the bioassay. The biosensor exhibited a low detection limit of 0.012 ng/mL, a broad linear range from 0.01 to 200 ng/mL, and a recovery rate of 95% to 105% in spiked human urine samples. This study demonstrates a novel hybrid 3D-printed flexible biosensor for 1-OHPG detection in urine, offering a simple, accurate, sensitive and cost-effective strategy with great potential for rapid, portable and reliable biomonitoring of wood smoke exposure.