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Low-temperature epitaxial growth of AlN ultrathin films was realized by atomic layer deposition (ALD) together with the layer-by-layer, in-situ atomic layer annealing (ALA), instead of a high growth temperature which is needed in conventional epitaxial growth techniques. By applying the ALA with the Ar plasma treatment in each ALD cycle, the AlN thin film was converted dramatically from the amorphous phase to a single-crystalline epitaxial layer, at a low deposition temperature of 300 °C. The energy transferred from plasma not only provides the crystallization energy but also enhances the migration of adatoms and the removal of ligands, which significantly improve the crystallinity of the epitaxial layer. The X-ray diffraction reveals that the full width at half-maximum of the AlN (0002) rocking curve is only 144 arcsec in the AlN ultrathin epilayer with a thickness of only a few tens of nm. The high-resolution transmission electron microscopy also indicates the high-quality single-crystal hexagonal phase of the AlN epitaxial layer on the sapphire substrate. The result opens a window for further extension of the ALD applications from amorphous thin films to the high-quality low-temperature atomic layer epitaxy, which can be exploited in a variety of fields and applications in the near future.

Geopolymers (GPs) are gaining prominence due to their low carbon emissions and sustainable attributes. However, one challenge with GPs, particularly those made with ground granulated blast furnace slag (GGBFS), is their significant shrinkage during the geopolymerization process, limiting its practical applicability. This study focuses on how the substitution ratio of metakaolin (MK) and the concentration of sodium hydroxide (NaOH) in the activator can influence the shrinkage and strength of a GGBFS-based GP. The experimental approach employed a 3 × 3 parameter matrix, which varied MK substitution ratios (0%, 50%, and 100%) and adjusted the NaOH concentration (6 M, 10 M, and 14 M). The results revealed that increasing MK substitution, particularly with 6 M NaOH activation, reduced the GP shrinkage but also diminished compressive strength, requiring higher NaOH concentrations for strength improvement. Statistical tools, including analysis of variance (ANOVA) and second-order response surface methodology (RSM), were employed for analysis. ANOVA results indicated the significant impacts of both the MK content and NaOH concentration on compressive strength, with no observable interaction. However, the shrinkage exhibited a clear interaction between MK content and NaOH concentration. The RSM model accurately predicted compressive strength and shrinkage, demonstrating a high predictive accuracy, for which the coefficients of determination (R ) were 0.99 and 0.98, respectively. The model provides a reliable method for determining the necessary compressive strength and shrinkage for GGBFS-based GP based on MK substitution and NaOH concentration. Within the optimization range, the RSM model compared with experimental results showed a 6.04% error in compressive strength and 0.77% error in shrinkage for one interpolated parameter set. This study establishes an optimized parameter range ensuring a GP performance that is comparable to or surpassing OPC, with a parameter set achieving a compressive strength of 34.9 MPa and shrinkage of 0.287% at 28 days.

Single molecular changes on a tripeptide can have dramatic effects on their self-assembly and hydrogelation. Herein, we explore C-terminal residue variation on two consistent ultrashort peptide backbones, i.e. acetylated-Leu-Ile-Val-Ala-Gly-Xaa and acetylated-Ile-Val-Xaa (Xaa = His, Arg, Asn). The objective of this study is to identify candidates that can form hydrogels for small-molecule drug (SMD) delivery. Haemolysis and cytotoxicity (with human adipose-derived mesenchymal stem cells) assays showed that the new soluble peptides (Xaa = His, Arg) are cytocompatible. Gelation studies showed that all but acetylated-Ile-Val-Arg could gel under physiological conditions. Longer peptidic backbones drive self-assembly more effectively as reflected in field emission scanning electron microscopy (FESEM) and circular dichroism spectroscopy studies. Rheological studies revealed that the resultant hydrogels have varying stiffness and yield stress, depending on the backbone and C-terminal residue. Visible spectroscopy-based elution studies with SMDs (naltrexone, methotrexate, doxorubicin) showed that besides the C-terminal residue, the shape of the SMD also determines the rate and extent of SMD elution. Based on the elution assays, infrared spectroscopy, and FESEM, we propose models for the peptide fibril-SMD interaction. Our findings highlight the importance of matching the molecular properties of the self-assembling peptide and SMD in order to achieve the desired SMD release profile.

The control rate of hypertension remains concerning, indicating the requirement for better management strategies. The calcium channel blockers brand‐name amlodipine and nifedipine with extended‐release formulations demonstrate similar clinical efficacy. However, the efficacy of generic nifedipine remains obscure. We compared the efficacy of generic nifedipine and brand‐name amlodipine in terms of cardiovascular (CV) outcomes. Patients prescribed generic nifedipine (SRFC CYH) or brand‐name amlodipine besylate (Norvasc, Pfizer) between August 1, 2017, and July 31, 2018, were enrolled; patients with CV events within 3 months were excluded. CV outcomes included CV death, nonfatal myocardial infarction (MI), nonfatal ischemic stroke, hospitalization for heart failure, and composite endpoints of 3P‐ and 4P‐major adverse cardiac events (MACE). A total of 1625 patients treated with nifedipine (SRFC CYH) and 16 587 patients treated with Norvasc were included. After propensity score matching, there were 995 and 4975 patients in the nifedipine CYH and Norvasc groups, respectively. At a mean follow‐up period of 30.3 ± 6.4 months, nifedipine CYH was comparable to Norvasc in terms of CV death (P = .107), nonfatal MI (P = .121), nonfatal ischemic stroke (P = .453), hospitalization for heart failure (P = .330), 3P‐MACE (P = .584), and 4P‐MACE (P = .274). Cox regression analysis revealed that nifedipine CYH and Norvasc had similar efficacy in terms of 3P‐MACE (hazard ratio, 0.970; 95% confidence interval, 0.601–1.565, P = .900) and 4P‐MACE (hazard ratio, 0.880; 95% confidence interval, 0.628–1.233, P = .459). In conclusion, Nifedipine SRFC CYH and Norvasc have comparable clinical efficacy for hypertension management.

This study aimed to assess the feasibility of utilizing geopolymer for repairing reinforced concrete beams. Three types of beam specimens were fabricated: benchmark specimens without any grooves, rectangular-grooved beams, and square-grooved beams. The repair materials employed included geopolymer material, and epoxy resin mortar, while carbon fiber sheets were used as reinforcement in select cases. The repair materials were applied to the rectangular and square-grooved specimens, with the carbon fiber sheets attached to the tension side of the specimens. To evaluate the flexural strength of the concrete specimens, a third-point loading test was conducted. The test results indicated that the geopolymer exhibited higher compressive strength and shrinkage rate compared to the epoxy resin mortar. Furthermore, the specimens reinforced with carbon fiber sheets demonstrated even greater strength than the benchmark specimens. In terms of flexural strength under cyclic third-point loading tests, the carbon fiber-reinforced specimens exhibited the ability to withstand over 200 cycles of repeated loading at 0.8 times the ultimate load. In contrast, the benchmark specimens could only withstand seven cycles. These findings highlight that the use of carbon fiber sheets not only enhances compressive strength but also improves resistance to cyclic loading.

The key objective of this study was to develop marble-based geopolymer concrete and examine the viability of its application as a sustainable structural material for the construction industry. The results of the research demonstrated that marble-based geopolymer concrete can be developed, and its physical/mechanical properties were shown to have a very good performance. According to various experimental tests and a large-scale ready-mixed plant test, it was found that the marble-based geopolymer concrete displayed a good workability and was not easily influenced by temperature changes. The results showed that marble-based geopolymer concrete has an excellent potential for further engineering development in the future.

Background Cathepsin S (CTSS) is a cysteine protease that played diverse roles in immunity, tumor metastasis, aging and other pathological alterations. At the cellular level, increased CTSS levels have been associated with the secretion of pro-inflammatory cytokines and disrupted the homeostasis of Ca 2+ flux. Once CTSS was suppressed, elevated levels of anti-inflammatory cytokines and changes of Ca 2+ influx were observed. These findings have inspired us to explore the potential role of CTSS on cognitive functions. Methods We conducted classic Y-maze and Barnes Maze tests to assess the spatial and working memory of Ctss −/− mice, Ctss + / + mice and Ctss + / + mice injected with the CTSS inhibitor (RJW-58). Ex vivo analyses including long-term potentiation (LTP), Golgi staining, immunofluorescence staining of sectioned whole brain tissues obtained from experimental animals were conducted. Furthermore, molecular studies were carried out using cultured HT-22 cell line and primary cortical neurons that treated with RJW-58 to comprehensively assess the gene and protein expressions. Results Our findings reported that targeting cathepsin S (CTSS) yields improvements in cognitive function, enhancing both working and spatial memory in behavior models. Ex vivo studies showed elevated levels of long-term potentiation levels and increased synaptic complexity. Microarray analysis demonstrated that brain-derived neurotrophic factor (BDNF) was upregulated when CTSS was knocked down by using siRNA. Moreover, the pharmacological blockade of the CTSS enzymatic activity promoted BDNF expression in a dose- and time-dependent manner. Notably, the inhibition of CTSS was associated with increased neurogenesis in the murine dentate gyrus. These results suggested a promising role of CTSS modulation in cognitive enhancement and neurogenesis. Conclusion Our findings suggest a critical role of CTSS in the regulation of cognitive function by modulating the Ca 2+ influx, leading to enhanced activation of the BDNF/TrkB axis. Our study may provide a novel strategy for improving cognitive function by targeting CTSS.

The aim of this study is to assess the process of synthesizing potassium-based geopolymers (KGL) into leucite ceramics with regard to five variables, namely, alkaline solution ratio (R), sintering time (S), calcining temperature (T), mixing time (M), and curing time (C). Under these conditions, the specimens were tested by the viscosity test, the mechanical properties test, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) to understand the geopolymerization reactions and the characteristics of the KGL network. The results indicate that a KOH to K2O/SiO2 ratio of 1:1 promotes the reaction within metakaolin. XRD analysis of the KGL shows that, when the temperature is 1100 °C, the phase transforms into the leucite phase. Moreover, XRD analysis, mechanical properties, and FTIR all indicate improved characteristics when the curing time increases from 1 to 8 h. This might be attributed to the enhancement of the strong interaction between the matrix and the alkaline solution upon achieving adequate time to complete the geopolymerization process and forming a more stable three-dimensional structure. The formulation which formed the purest leucite phase consisted of: a 1:1 alkaline solution ratio, 10 min mixing time, 8 h curing time, 1200 °C calcining temperature, and 2 h sintering time.

Background The heart and kidneys had demonstrated a bidirectional interaction that dysfunction of the heart or kidneys can induce dysfunction in the other organ. Hypothesis Renal function and its decline during hospitalization may have impact on cardiovascular outcomes in patients with acute decompensated heart failure (ADHF). Methods A total of 119 consecutive Chinese patients admitted for ADHF were prospectively enrolled. The course of renal function was presented with estimated glomerular filtration rate (eGFR), calculated by the four‐variable equation proposed by the Modification of Diet in Renal Disease (MDRD) Study. Worsening renal function (WRF) was defined as eGFR decline between admission (eGFRadmission) and predischarge (eGFRpredischarge). Clinical outcomes were defined as 4P‐major adverse cardiovascular events (4P‐MACE), including the composition of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, and nonfatal HF hospitalization. Results During an average 2.6 ± 3.2 years follow‐up, 66 patients (55%) experienced 4P‐MACE. Patients with impaired eGFRpredischarge (<60 ml/min/1.73 m2) had more 4P‐MACE than those with preserved eGFRpredischarge (64.7% vs. 43.1%, p = .019). The Kaplan–Meier survival curves showed significantly higher incidence of 4P‐MACE in patients with impaired eGFRpredischarge than those with preserved eGFRpredischarge (p = .002). Cox regression analysis revealed that impaired eGFRpredischarge was significantly correlated with the development of 4P‐MACE (hazard ratio, 2.003; 95% confidence interval, 1.072–3.744; p = .029). In contrast, outcomes would be similar with regard to eGFR on admission and eGFR decline during hospitalization. Conclusions Impaired renal function before discharge, but not impaired renal function on admission or WRF, is a significant risk factor for poor outcomes in patients with ADHF.

This study investigates sustainable alternatives for thermal regulation in building materials by incorporating modified basic oxygen furnace slag (MBOFS) as a partial replacement for natural aggregates in concrete. MBOFS was produced by injecting oxygen and silica sand into molten BOF slag to reduce free CaO and MgO, enhancing stability and suitability for cementitious composites. Characterization revealed high mid-infrared emissivity (up to 95.92% in the 8–13 μm range), low solar reflectivity, and high absorptance—properties favorable for passive radiative cooling. Optical, physical, mechanical, and thermal evaluations included spectral analysis, tests for density, porosity, compressive strength, and indoor irradiation with heat flux and temperature monitoring. Increasing MBOFS content raised thermal resistance from 0.034 to 0.069 m2·K/W and lowered thermal transmittance from 3.644 to 3.235 W/m2·K. Higher heat storage capacity and higher emissivity (thermal radiation) suppress the thermal transmittance, thus improving the thermal resistance of the building walls. The 60% replacement showed the most balanced surface thermal response, whereas higher ratios yielded greater energy retention. These results demonstrate that MBOFS can enhance insulation, radiative cooling, and mechanical performance, advancing climate-responsive concrete for urban heat island mitigation.