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关键词： Glucagon   Pancreatic alpha-cell   Sodium-glucose cotransporter 1   Type 2 diabetes  

摘要： Pancreatic alpha-cells secrete glucagon, a hormone that elevates blood glucose levels. In type 2 diabetes, high plasma glucagon levels are associated with hyperglycemia. However, the underlying mechanisms of increasing glucagon secretion remain unclear. We focused on the intrinsic regulatory mechanisms of glucagon secretion in alpha-cells, in particular sodium- glucose cotransporter 1 (SGLT1), which is involved in the early steps of glucose sensing. We previously demonstrated that SGLT1 is expressed in alpha-cells and is significantly upregulated in diabetic mice compared with non-diabetic mice. In isolated islets from diabetic mice, SGLT1 knockdown attenuated glucagon hypersecretion, and in alpha TC1 cells, SGLT-specific substrates promoted glucagon secretion by raising intracellular calcium. On the basis of these findings, we hypothesized that SGLT1 upregulation in alpha-cells under diabetic conditions impairs the suppression of glucagon secretion, thereby contributing to hyperglycemia. However, a previous study showed that systemic SGLT1 knockout (KO) mice exhibit a higher proportion of alpha-cells in the islets and atypically high plasma glucagon levels. To clarify the roles of SGLT1 specifically in alpha-cells, we generated alpha-cell-specific SGLT1 KO mice using a tamoxifen-inducible Cre-loxP system and analyzed these mice fed a highfat, high-sucrose diet. The results clearly showed that, inconsistent with the results from the systemic SGLT1 KO mice, SGLT1 deficiency specifically in alpha-cells did not affect glucagon secretion, glucose tolerance, or alpha-cell proportion in the islets under diabetic conditions. Thus, though SGLT1 is upregulated in diabetic alpha-cells, this does not appear to contribute to hyperglucagonemia and impaired glucose tolerance in diabetic mice.

关键词： Biomass gasification   Performance optimisation   Statistical analysis & modelling  

摘要： The advanced dual fluidised bed steam gasification process can provide a versatile product gas from biomass residues and waste materials, applicable for different downstream syntheses processes. In Austria, current research utilises a demonstration scale plant to investigate fuel flexibility and optimise key performance parameters in an industrial environment. However, the dual reactor principle is a system with many potential interactions between its operating parameters which are difficult to distinctly evaluate. The design of experiments method as a statistical approach to experimental investigation can help to identify and quantify these interactions, as shown in multiple fields and industries. With the use of this method, a two-week experimental campaign (111 h) with the demonstration plant was planned and executed. In total, 19 individual operating points were investigated, and the resulting data was analysed to evaluate suitable settings for the generation of a product gas suited for downstream Fischer-Tropsch synthesis, with the aim of increasing conversion efficiency and product gas quality. Furthermore, results should provide plant operates with easy-to-understand instructions for plant operation with respect to specific in- and outputs. The data evaluation led to a first rudimentary system mapping of the reactor system, over a wide range of four main operating parameters. This first ever application of statistical methods in this process' scale shows that the approach is suited for this technology. The presented results provide a base for further system analysis and help future experimental campaigns and the ongoing technology optimisation process.

关键词： Biodiesel   Mn doping   Oxygen vacancies   Perovskite   Transesterification  

摘要： The coexistence of free fatty acids (FFAs) and moisture in biodiesel feedstock oils poses major limitations for conventional basic catalytic systems, which motivates the development of heterogeneous catalysts capable of promoting transesterification and esterification. In this work, a Mn-doped perovskite catalyst, BiFe_0.7Mn_0.3O₃, was synthesized using BiFeO₃ as the matrix for biodiesel preparation. Mn doping disrupted the lattice charge balance of BiFeO₃, which induced lattice distortion and promoted the formation of oxygen vacancies. These structural changes regulated the surface electronic environment and optimized the distribution of acidic-basic active sites. Under optimized reaction conditions of 140 °C, 3.5 h, methanol-to-oil molar ratio of 14:1, and catalyst amount of 3.0 wt%, BiFe_0.7Mn_0.3O₃ achieved a biodiesel yield of 95.20%. Even in reaction systems containing 30 wt% FFAs or 8 wt% moisture, the biodiesel yield remained above 80.00%, which confirms its strong resistance to FFAs and moisture-containing feedstocks. Mechanistic analysis reveals that Mn doping-induced oxygen vacancies create an optimized surface acid-base environment that enables the simultaneous promotion of transesterification and esterification reactions. Moreover, BiFe_0.7Mn_0.3O₃ exhibits favorable magnetic responsiveness, which enables rapid separation and recovery under an external magnetic field after reaction. Combined with the low synthesis cost and recyclability, this catalyst shows strong potential for sustainable biodiesel preparation from low-quality feedstock oils.

关键词： Algal biofuel   Aviation fuel   Chlorella variabilis   JET-A1   Sustainable aviation fuels  

摘要： Sustainable aviation fuels such as Algal biofuels are emerging as a promising alternative to fossil-based aviation fuels due to their renewable nature, high yield potential, and lower environmental impact, warranting extensive research into their performance and viability. Although earlier research has primarily concentrated on algal cultivation and fuel production processes, experimental validation of algal biodiesel blends under engine-level combustion and emission remains limited. The study evaluates the combustion efficiency, energy output, and emission performance characteristics of JET-A1 aviation fuel blended with hydrodeoxygenated algal biodiesel at volumetric ratios of 10:90, 20:80, and 30:70. The prepared blends were then characterized in accordance with the ASTM D1655 standards, and engine performance was assessed using a diesel engine under variable load conditions. Among the tested fuels, the 80:20 blend (JF80HAOBD20) demonstrated superior performance, recording a peak cylinder pressure of 49.1 bar, a maximum heat release rate of 28.76 J/deg, and a mean gas temperature of 1052.43 K. Importantly, it maintained brake thermal efficiency and specific fuel consumption comparable to pure Jet-A1. Emission analysis of the optimal fuel blend (JF80HAOBD20) demonstrated approximately 15% lower carbon monoxide emissions and 10 % lower nitrogen oxide emissions, along with significantly reduced smoke opacity (1.3 %) compared to standard Jet-A1. By integrating ASTM-compliant fuel characterization, FTIR-based confirmation of transesterification, and combustion diagnostics under controlled load conditions, this work provides comprehensive engine-level validation. The findings are systematically analyzed and compared against conventional Jet-A1 aviation fuel. These findings underscore the potential of algal biofuels as sustainable alternatives in aviation fuel applications.

关键词： Biomass gasification   Performance optimisation   Statistical analysis & modelling  

摘要： The advanced dual fluidised bed steam gasification process can provide a versatile product gas from biomass residues and waste materials, applicable for different downstream syntheses processes. In Austria, current research utilises a demonstration scale plant to investigate fuel flexibility and optimise key performance parameters in an industrial environment. However, the dual reactor principle is a system with many potential interactions between its operating parameters which are difficult to distinctly evaluate. The design of experiments method as a statistical approach to experimental investigation can help to identify and quantify these interactions, as shown in multiple fields and industries. With the use of this method, a two-week experimental campaign (111 h) with the demonstration plant was planned and executed. In total, 19 individual operating points were investigated, and the resulting data was analysed to evaluate suitable settings for the generation of a product gas suited for downstream Fischer-Tropsch synthesis, with the aim of increasing conversion efficiency and product gas quality. Furthermore, results should provide plant operates with easy-to-understand instructions for plant operation with respect to specific in- and outputs. The data evaluation led to a first rudimentary system mapping of the reactor system, over a wide range of four main operating parameters. This first ever application of statistical methods in this process’ scale shows that the approach is suited for this technology. The presented results provide a base for further system analysis and help future experimental campaigns and the ongoing technology optimisation process.

摘要： Synergistic interaction gels hold significant promise for applications in food engineering and biomedicine. This study investigates how 1,2-propanediol (PDO), as a cosolvent, influences the gelation behavior and microstructure of synergistic gels prepared from partially de-galactosylated tamarind gum (GRT) and xanthan. Results indicate that PDO modulates conformational transitions, chain association and molecular interactions between GRT and xanthan by dehydrating polysaccharide chains and increasing hydrophobicity of solvent. With increasing PDO concentration, it promotes the self-association of xanthan and GRT, as reflected by the increased exothermic peak and enlarged of scattering entity (d₁ and ξ₁). Concurrently, at lower temperature, PDO dissociates from GRT clusters formed at higher temperature. The released PDO further increases the solvent hydrophobicity, thereby inducing synergistic interaction between xanthan and GRT. Together, these effects enhance the physical cross-linking within the gel network, resulting in a stronger gel with higher storage modulus and gel hardness. However, at higher PDO levels (>15%), pronounced dehydration leads to excessive self-aggregation of GRT and thickening of xanthan helical bundles, which promotes phase separation, compromises network homogeneity, and ultimately reduces gel strength. This work elucidates the concentration-dependent regulatory role of PDO in gel-network formation, providing theoretical guidance for the design of advanced polysaccharide-based composite materials.

关键词： Autism Spectrum Disorder   Latino Families   Community-Based Participatory Research   Phase 1 Clinical Trial   Intersectionality  

摘要： This study presents a qualitative examination of a Phase 1 clinical trial evaluating ¡Iniciando!, a culturally adapted intervention for Latino autistic young adults and their families. Employing a community-based participatory research (CBPR) approach, we gathered feedback from parents (n = 46) and young adults (n = 46; Mean Age = 20.53, SD = 2.15) through open-ended surveys and rankings of program modules and optional webinars. Inductive thematic analysis revealed significant perceived benefits, including enhanced social connections, practical life skills, and personal understanding. Parents and young adults provided valuable suggestions for program improvement, emphasizing the need for increased social interaction, personalized content, and flexible scheduling. The program's cultural fit was positively rated, with participants highlighting the importance of Spanish language use and incorporation of Latino cultural values. Findings provide preliminary support for integrating cultural responsiveness and neurodiversity-affirming practices in interventions for this underserved population, informing future program refinements and dissemination.

关键词： Lagrange multipliers  

摘要： Optimizing classification evaluation metrics naturally results in a model comprising the composition of the 0/1 loss function and a linear term. The augmented Lagrangian Method (ALM) has stood out as a leading methodology for such problems. The main purpose of this paper is to extend the classical theory of ALM from smooth problems to 0/1-loss composite optimization arising from classification. We propose, for the first time, second-order optimality conditions for this problem. In particular, under a second-order sufficient condition (SOSC), we prove linear convergence rate of the proposed ALM. In order to identify the subspace used in SOSC, we employ the proximal operator of the 0/1 loss function, leading to an active-set identification technique. Built around this identification process, we design practical stopping criteria for any algorithm to be used for the subproblem of ALM. We justify that Newton’s method is an ideal candidate as a subroutine and it enjoys global convergence with local quadratic rate. Those considerations result in an inexact Newton ALM (iNALM). The method of iNALM is distinctive because the Newton subroutine, inexact criterion, and SOSC are all active-set based. These elements play an important role in its linear convergence analysis. The numerical results on both simulated and real datasets show the fast running speed and high accuracy of iNALM when compared with several leading solvers.

关键词： 镁植入物   整合素α10β1   成骨分化   骨膜干细胞   骨再生   Wnt/β-catenin信号通路   骨修复   骨质疏松  

摘要： 背景:骨膜干细胞是镁诱导新骨形成的关键细胞群。整合素α10β1是一类依赖Mg2+的异型细胞黏附分子,Mg2+可与整合素α10β1中的MIDAS结构域结合,作为分子开关调控下游生物学过程。目的:探究镁基植入物通过激活整合素α10β1调控骨膜干细胞成骨分化的机制。方法:将42只C57BL/6小鼠随机分为钛棒植入组(n=21)与镁棒植入组(n=21),分别在左侧膝关节股骨髁间窝骨髓腔内植入钛棒、镁棒,术后3 d取材,Tunel染色观察植入物周围细胞凋亡情况,Edu染色观察皮质骨增厚区域细胞增殖活性;术后14 d取材,Micro-CT分析股骨皮质骨增厚成骨情况,苏木精-伊红染色观察股骨皮质骨增厚区新生骨形态结构,钙黄绿素荧光双标染色分析骨膜干细胞成骨分化情况,qPCR检测成骨标志基因Runx2、成骨细胞特异性转录因子、碱性磷酸酶、骨唾液酸蛋白以及整合素α10、整合素β1表达,Western blot检测整合素α10、整合素β1、黏着斑激酶及磷酸化黏着斑激酶蛋白表达,转录组测序分析Wnt/β-catenin、丝裂原活化蛋白激酶信号通路表达以及整合素α10β1与成骨基因表达之间的相关性。结果与结论:①Tunel染色与Edu染色显示,钛棒周围聚集大量凋亡细胞,骨膜区域仅见少量增殖细胞,无成骨分化;镁棒周围无凋亡细胞,骨膜增厚区域增殖细胞明显增多。②Micro-CT分析显示,钛棒未降解,镁棒降解明显,镁棒植入组皮质骨增厚成骨情况优于钛棒植入组。苏木精-伊红与钙黄绿素荧光双标染色显示,镁棒植入组皮质骨增厚成骨情况优于钛棒植入组。qPCR检测结果显示,镁棒植入组Runx2、成骨细胞特异性转录因子、碱性磷酸酶、骨唾液酸蛋白、整合素α10、整合素β1 mRNA表达高于钛棒植入组;Western blot检测结果显示,整合素α10、整合素β1、黏着斑激酶及磷酸化黏着斑激酶蛋白以及Wnt/β-catenin表达高于钛棒植入组,丝裂原活化蛋白激酶表达低于钛棒植入组。转录组测序分析显示,整合素α10β1与Runx2、成骨细胞特异性转录因子、碱性磷酸酶、骨唾液酸蛋白表达具有显著的正相关性。③结果表明,镁基植入物通过激活整合素α10β1-黏着斑激酶/磷酸化黏着斑激酶信号通路上调Wnt/β-catenin信号、抑制部分丝裂原活化蛋白激酶信号,从而促进骨膜骨干细胞的成骨分化。