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关键词： Critical behavior   Ferromagnetic-paramagnetic   Magnetic entropy   Magnetocaloric effect   Nanoparticles   Specific heat  

摘要： In this work, we investigate the effect of phase separation on the magnetic characteristics of La_1-xCs_xMnO₃ (0 ≤ x ≤ 0.1) manganites (LCMO). The nature of the magnetic transitions in LCMO nanoparticles has been fully studied in a large range of temperature, by AC susceptibility, specific heat, DC magnetization, magnetocaloric and critical behaviors. Non-conventional LaMnO₃ behavior has been observed as well as an unexcepted decreasing of ferromagnetic order with increasing Cs doping. The detailed analysis of the critical exponent as well as the universal curves suggests, in coherence with the specific heat results, that short-range ferromagnetic interactions are dominant in all our samples. A cogent picture based on a phase separation scenario is presented, suggesting a delicate balance between long and short-range interactions strongly controlled by the Cs doping. This work clearly shows that traditional perturbative models are not adapted for the whole range of composition explored, indicating that these models cannot represent a distribution of ordering temperatures in phase separated nanostructures. Finally, the magnetic entropy changes (ΔS) were calculated from magnetization data using Maxwell's relation. The maximum value of ΔS under a magnetic field change of 5 T is found to be 3.80, 2.32 and 1.56 J/kgK, respectively for x = 0, 0.05 and 0.1. The corresponding relative cooling power reaches 220 J/kg for the smallest Cs-doping which can be considered interesting for magnetic refrigerants technology in the sub-room temperature range [120K200K].

关键词： TRH   Nucleus accumbens   Central nucleus of amygdala   Feeding behavior   Anorexia   Electrical stimulation  

摘要： Thyrotropin-releasing hormone (TRH) is a hypothalamic neuropeptide that directs the thyroid axis function. Beyond this classical role, TRH is also synthesized in extrahypothalamic brain regions, where it is implicated with anorectic, anxiolytic and antiepileptic effects. Its anorectic role is supported by the reduced food intake of fasted rats when refed, after TRH is injected into their nucleus accumbens (NAc). The central nucleus of the amygdala (CeA) contains TRHergic cells, and its electrical stimulation (ES) induces a hypophagic effect on rats and transsynaptic changes in TRH content in the NAc and other brain regions. Since the G-protein-coupled type-1-TRH receptor is expressed in the NAc, we evaluated its participation in ES-amygdala-induced feeding regulation by using the electrical amygdaloid kindling model and by injecting antisense oligonucleotides (ASO) against type-1 TRH receptor (TRH-R1) in the NAc of rats. Male Wistar rats with an implanted electrode in CeA received daily ES (1 s, 60 Hz, 1 ms pulses) for seven days; then, fasted 48-h and on day 10, receiving a last ES, and refed for 2 h. Amygdala TRH mRNA expression was analyzed by in situ hybridization, while accumbal pro-TRH content by Western blot and immunohistochemistry. Amygdalar stimulation increased TRH mRNA in CeA, cortical amygdala and medial amygdalar nucleus; pro-TRH content increased in shell of NAc. Importantly, intra-NAc shell administration of ASO targeting TRH-R1, reversed the reduced food intake induced by CeA stimulation. These findings support the functional role of TRH-R1 in the NAc for the CeA electrical stimulation-induced hypophagia observed in re-fed fasted rats.

关键词： Terpinen-4-ol   1,8-Cineole   Nanoemulsions   Chitosan   Antibacterial  

摘要：

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  Artificial formulation has higher antibacterial activity than tea tree oil (TTO).
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  The formation and physical properties of nanoemulsions is studied systematically.
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  Nanoemulsions exhibit superior antibacterial efficacy than reported nano-TTO.
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  Chitosan and the essential oil components exhibit a synergistic antibacterial effect.

关键词： Acute lung injury   Calpain-1   Hydroxysafflor yellow A   Hypoxia-inducible factor-1α   Pulmonary microvascular endothelial barrier  

摘要： Pulmonary microvascular endothelial cell (PMEC) barrier dysfunction is a critical pathological hallmark of acute lung injury (ALI). Hydroxysafflor yellow A (HSYA), a major active component of safflower, exhibits potential protective effects against lung injury. The current study aimed to investigate whether HSYA preserves PMEC barrier integrity in lipopolysaccharide (LPS)-induced ALI by inhibiting the Calpain-1/hypoxia-inducible factor-1α (HIF-1α) pathway.

关键词： Component method   EN1993-1-8   Failure mode   Resistance   T-stubs   Yield pattern  

摘要： This paper presents the results of a comprehensive experimental study on 64 unstiffened T-stubs. All three failure modes defined in Eurocode EN 1993-1-8 were systematically examined by varying key parameters such as flange plate thickness, bolt-to-stem distance, edge distance, bolt diameter, and bolt grade. The experimental findings revealed average test-to-predicted strength ratios of 1.35 and 1.21 for Method 1 and Method 2 of EN 1993-1-8, respectively. For more than 15 specimens, however, the existing design model failed to accurately predict the failure mode. Classical double-curvature yielding was observed in the majority of specimens. However, some specimens displayed a distinct yield pattern, characterized by single-curvature yielding with corner yielding—behavior not explicitly addressed in the Eurocode. To resolve these discrepancies, the study proposes modifications to geometric parameters and introduces an additional yield pattern that incorporates the observed single-curvature yielding with corner yielding. These adjustments reduced the average test-to-predicted strength ratio to 1.06 and significantly improved the accuracy of both failure mode and yield pattern predictions. As part of the investigation, both ultimate and plastic resistances were evaluated. The average ratio of ultimate to plastic resistance was found to be 2.49, indicating a substantial reserve strength beyond the plastic limit. The proposed yield pattern was also validated through finite element analyses.

摘要： The timing of Yellow River integration through the Sanmen Gorge remains highly debated, with proposed ages ranging from ∼5 Ma to ∼0.15 Ma. This uncertainty largely reflects discontinuous stratigraphic records and insufficient multi-proxy constraints from the Fenwei Basin. Here, we present a 600.15 m continuous sediment core (YJ-1) from the western Yuncheng Basin, providing a ∼3.59 Ma paleoenvironmental archive from a key sector of the Fenwei Basin. Integrating sedimentary facies analysis, magnetostratigraphy, grain-size end-member modeling, ostracod assemblages, color reflectance, magnetic susceptibility, and detrital zircon U–Pb age spectra, we identify four distinct depositional stages: (I) stable lacustrine (∼3.59–2.1 Ma), (II) lacustrine-to-fluvial transitional (∼2.1–1.8 Ma), (III) fluvial-dominated (∼1.8–0.076 Ma), and (IV) aeolian (∼0.076 Ma–present). A pronounced multi-proxy shift at ∼1.8 Ma (466.7 m depth), characterized by abrupt changes in sedimentary facies, grain-size distributions, ostracod assemblages, environmental proxies, and provenance evidence, marks an irreversible lacustrine-to-fluvial transition. This transformation coincides with the widespread lacustrine-to-aeolian facies shift across the Fenwei Basin, signaling a fundamental reorganization of the hydrological and ecological system that heralds the initiation of Yellow River integration through Sanmen Gorge. By integrating our findings with regional tectonic and climatic records, we propose that the far-field tectonic effects of Tibetan Plateau uplift, coupled with the intensification of the East Asian Summer Monsoon, jointly drove this drainage reorganization. These findings advance our understanding of the complex interplay among tectonics, climate, and surface processes during major river system expansion.

关键词： 3D printing   Biocompatibility   Chondroitin sulfate   Collagen   Crosslinking  

摘要： Collagen and chondroitin sulfate scaffolds were fabricated using 3D printing. Once printed, the scaffolds were divided into three groups. Two of these groups were subjected to a chemical crosslinking treatment with 1,4-butanedioldiglycidyl ether at different concentrations, while the last group remained uncrosslinked. Fourier Transform Infrared Spectrometry analysis indicated that for higher BDDE concentrations, the scaffolds showed higher cross-linking and denaturation degree. The crosslinking treatment enhanced the mechanical properties of the scaffolds, increasing their resistance to collagenase degradation and reducing their solubility under physiological conditions. Scanning electron microscopy and porosity test revealed that all the scaffolds showed an adequate range of porosity. Furthermore, according to ISO 10993-5, none of the three groups of scaffold extracts were cytotoxic, with cell viability greater than 70% using Vero cells. Finally, in vitro evaluation using BJ line cells from human skin demonstrated that all scaffolds allowed cell attachment and proliferation. Based on these results, the obtained scaffolds exhibited adequate characteristics and properties for their possible application in soft tissue engineering.

关键词： Cubic Halin graph   Induced matching   S-packing edge-coloring  

摘要： For a non-decreasing positive integer sequence $S=(s_1,\dots ,s_k)$, an $S$-packing edge-coloring of a graph $G$ is a decomposition of edges of $G$ into disjoint sets $E_1$, $\dots ,$ $E_k$ such that for each $1\le i\le k$ the distance between any two distinct edges $e_1$, $e_2\in E_i$

关键词： Intramolecular charge transfer   Chemosensor   Limit of detection   Association constant   Real water apllication   BODIPY  

摘要： Acetyl acetone bearing BODIPY chemosensor (ABDP) was designed and successfully synthesized by refluxing BDPHY and acetyl acetone in methanol. ABDP selectively detects Hg²⁺ ions through an intramolecular charge transfer (ICT) mechanism. A distinct turn-on response of the chemosensor towards Hg²⁺ ions was observed, accompanied by a noticeable naked-eye colour change. The fluorescence emission intensity of ABDP increased with a concomitant blue shift upon the addition of Hg²⁺ ions. The sensing ability of the chemosensor depends on its cavity size and electron donor site O of acetyl acetone and N atom of ABDP. ABDP has a large cavity that effectively binds Hg²⁺ ions. The sensor exhibits a high binding constant (10⁴ M⁻¹) and a low detection limit (10⁻⁷ M). Furthermore, ABDP demonstrates practical applicability for the detection of Hg²⁺ ions in real water samples, including tap water, pond water, and coal water.