Search Results (1,604)

Developing more effective gold–support synergy is essential for enhancing the catalytic performance of supported gold nanoparticles (AuNPs) in the gas-phase oxidation of ethanol to acetaldehyde (AC) at lower temperatures. This study demonstrates a significantly improved Au–support synergy achieved by copper doping in LaMO₃ (M = Mn, Fe, Co, Ni) perovskites. Among the various Au/LaMCuO₃ catalysts, Au/LaMnCuO₃ exhibited exceptional catalytic activity, achieving an AC yield of up to 91% and the highest space-time yield of 764 g_AC g_Au⁻¹ h⁻¹ at 225 °C. Notably, this catalyst showed excellent hydrothermal stability, maintaining performance for at least 100 h without significant deactivation when fed with 50% aqueous ethanol. Comprehensive characterization reveals that Cu doping facilitates the formation of surface oxygen vacancies on the Au/LaMCuO₃ catalysts and enhances Au–support interactions. The LaMnCuO₃ perovskite stabilizes the crucial Cu⁺ species, resulting in a stable Au-Mn-Cu synergy within the Au/LaMnCuO₃ catalyst, which facilitates the activation of O₂ and ethanol at lower temperatures. The optimization of the reaction conditions further improves AC productivity. Kinetic studies indicate that the cleavages of both the O-H bond and the α-C-H bond of ethanol are the rate-controlling steps. Full article

Paeonia suffruticosa Andr. (tree peony) and Paeonia lactiflora Pall. (herbaceous peony) are traditional Chinese flowers with great ornamental value. To maintain the aesthetic value and show the characteristics of these species, preserved flowers named ‘germplasm display balls’ were developed. Firstly, dried flowers were obtained by vacuum freeze-drying. Secondly, to embed dried flowers and develop germplasm display balls, highly transparent crystal glue (in wrapped display balls type 1 and drop-type display balls type 2) and highly transparent silicone gel (in wrapped display balls, type 3) were used. Finally, the first pass yield (FPY), labor productivity (LP), average cost (AC), and popularity of three kinds of germplasm display balls were compared. The results showed that with the support of a paper cup, the deformation rate of flowers significantly decreased by 91.11%. The FPY of dried flowers was as high as 98.89% at 18 °C. The optimal process for type 1 and type 2 was a glue dosage of 20 g, stirring time of 3 min, and room temperature of 25 °C. Although there was a higher AC in type 3 display ball process, moderate LP and higher FPY and popularity than in other two types, accompanied by high durability, render it the best choice. Full article

The large-scale integration of renewable energy sources and new loads, such as distributed photovoltaics and electric vehicles, has resulted in frequent power quality issues within distribution networks. Traditional AC distribution networks lack the necessary flexibility and have limited capacity to accommodate these new energy sources and loads. Transforming the conventional distribution network into an AC-DC hybrid network using flexible interconnection devices like Voltage Source Converters can enhance the network’s flexibility, mitigating the power quality challenges arising from the integration of renewable energy and new loads. Electric buses, with their substantial capacity, mobility, and centralized management, offer potential as mobile energy storage. They can participate in the dispatching of the distribution network, thereby improving the network’s flexibility in power regulation. This paper proposes a coordinated optimization approach that integrates electric buses and VSCs for distribution network dispatch. This method enables electric buses to assist in power dispatch without interfering with their primary public transport duties, thus enhancing the network’s capacity to absorb new energy sources and loads. Firstly, considering the mobility characteristics of electric buses, a multi-layer stochastic Time–Space Network model is developed for bus dispatching. Secondly, an optimization model is constructed that accounts for the coordination of charging and discharging power between VSCs and electric buses, with the objective of minimizing the network losses in the distribution system. Finally, the proposed model is transformed into a second-order cone programming formulation, facilitating its solution through convex optimization techniques. The effectiveness of the proposed approach is demonstrated through a case study. Full article

The second messenger cAMP plays multiple critical roles in the control of sperm functions essential for male fertility, including motility. The enzyme soluble adenylyl cyclase (sAC; ADCY10) was shown genetically and pharmacologically to be the essential source of cAMP mediating many of these functions. Male mice and men with genetic deletions of sAC are infertile, and their sperm are progressively immotile. Pharmacologically, delivery of potent and specific sAC inhibitors to male mice renders them temporarily infertile, and their sperm are similarly immotile. Here, we show that males from a second, independently derived mouse sAC knockout line are also infertile with progressively immotile sperm. We use these mouse models to determine optimal conditions for pharmacologically elevating intracellular cAMP to rescue the sAC null motility defect. We show that cell-permeable cAMP analogs, but not forskolin, rescue the motility defects of sAC deficient sperm, and we demonstrate that 8Br-cAMP is an efficient cAMP analog to rescue motility. Full article

The increasing demand for electricity and the imperatives of climate change have made the optimization of power system planning critical for the energy transition and grid efficiency. This study presents an innovative planning method for inter-regional AC-DC hybrid power systems, leveraging the Classification and Regression Tree (CART) algorithm to optimize the operational characteristics of direct current (DC) channels. By designing a closed-loop iteration, precise operational constraints are considered by the CART algorithm, which immerged into the planning model to achieve safe and economic optimization. Based on the empirical analysis of the HRP-38 system, this study concludes that the CART algorithm offers a constructive approach to managing the operational complexities of modern power grids. By optimizing and refining DC operational characteristics based on actual system requirements, the algorithm contributes to improvements in safety, economic efficiency, and environmental sustainability within the confines of the HRP-38 node system. Consequently, the effectiveness of the CART optimization approach could be corroborated. Meanwhile, this study also acknowledges the limitations in generalizing these results to other power grid configurations and the need for further exploration in developing environmentally conscious planning methods. Full article

The biotechnological production of carotenoids offers a promising alternative to their chemical synthesis or extraction from plants. Mycolicibacterium species have shown potential as pigment-producing microorganisms. However, bacterial strains typically exhibit lower productivity compared to fungal and yeast strains. Earlier, we enhanced the β-carotene biosynthesis in M. neoaurum strain VKM Ac-3067D by modifying the cultivation medium. Key changes included replacing glucose with glycerol and soybean meal with skimmed milk powder (SMP) and increasing the urea content from 0.5 to 1.0 g/L. To further optimize β-carotene yield, a steepest ascent method was applied combining factorial design with a gradient-based optimization (Wilson–Box method). The resulting regression model showed that the most influential factors were the glycerol concentration and SPM use. The in-flask fermentation of the Ac-3067D strain in a medium containing 25.5 g/L of glycerol (carbon source) and 12.80 g/L of SMP (nitrogen source) increased β-carotene yield to 318.4 ± 8.3 mg/kg. In a 15 L bioreactor, β-carotene yield increased to 432.3 ± 10.4 mg/kg, while the biomass concentration reached 23.2 ± 1.2 g/L. The further scaling up to a 100 L bioreactor increased both β-carotene yield (450.4 ± 8.2 mg/kg) and biomass concentration (25.2 ± 1.1 g/L). Thus, β-carotene production technology using the M. neoaurum strain AC-3067D was successfully scaled up from 750 mL flasks to a 100 L bioreactor, confirming its potential for industrial-scale application. Full article

Effective available treatment options for patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who relapse after becoming refractory to both a covalent Bruton Tyrosine Kinase inhibitor (cBTKi) and a B cell leukemia/lymphoma 2 inhibitor (BCL2i) remain limited, and prognosis is very poor. Emerging areas of drug development include cellular therapies such as chimeric antigen receptor T-cell therapy and bispecific antibodies. However, cost, accessibility, toxicity, and the need for either prolonged or repeated hospitalization prevent universal application of these therapies. Given this area of unmet clinical need, we present this review article on Bruton Tyrosine Kinase (BTK) degraders in patients with CLL/SLL. We focus on their development as a drug class, the up-to-date clinical data available, as well as future directions. BTK protein degraders are a novel drug class with an alternate mechanism of action (MOA), compared to cBTKis and non-covalent BTKis (ncBTKis), causing ubiquitination of BTK, thereby leading to its degradation through the proteasome. Encouraging pre-clinical data show that this MOA allows BTK protein degraders to overcome common BTK mutations. We focus on four agents which are under investigation in B-cell malignancies in early clinical trials: BGB-16673, NX-2127, NX-5948, and AC676. Preliminary data suggest a comparable safety and toxicity profile between agents across this drug class with many patients on phase 1 trials deriving durable clinical benefit. Optimal sequencing of BTK degraders in the therapeutic landscape of CLL/SLL treatment is yet to be established. Further trials investigating these agents in combination with other targeted CLL agents may help to further understand their applicability. An effective, tolerable oral class of drugs would be invaluable in the treatment of patients with multiply relapsed CLL/SLL. Full article

This study examines the variability of sialic acids, specifically N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc), in beef from seven cattle breeds (Holstein Friesian, Red Pied, Maremmana, Chianina, Charolais, Limousin, and Piemontese). Neu5Gc, a non-human sialic acid linked to inflammation and disease risk, showed significant breed differences (p < 0.001), with the highest concentration in Holstein Friesian (61.02 µg/g) and the lowest in Piemontese (20.87 µg/g). Neu5Ac, known for its neuroprotective properties, was most abundant in Piemontese (112.99 µg/g, p = 0.032) and lowest in Limousin (81.25 µg/g). The Neu5Ac/Neu5Gc ratio, critical for dietary health, exceeded the threshold of 5:1 only in Piemontese (5.49), identifying it as a breed with a higher ratio. This study highlights the influence of breed, with limited effects of muscle type and aging, on sialic acid content. Significant correlations were observed between Neu5Gc and fatty acid classes (p < 0.05) and between Neu5Ac and polar amino acid groups (p < 0.01). The findings support selective breeding to optimize beef’s nutritional profile, enhancing its health benefits for consumers. Full article

UHV (ultra-high voltage) by instant AC transmission system is accompanied by huge reactive power transmission. When the load drops sharply, it is easy to produce serious power frequency overvoltage, which is also defined as load rejection overvoltage. This paper makes an in-depth analysis from the perspective of voltage increase caused by instantaneous load unloading, and obtains the causes and key influencing factors of load rejection overvoltage. Taking the UHV AC transmission line of a practical project as an example, the suppression effect of the suppression strategy represented by the installation of opening resistance and shunt reactor on the load rejection overvoltage is analyzed. The simulation results show that the above method has an obvious inhibitory effect on load rejection overvoltage. Based on the optimal suppression principle, the optional interval range of the opening resistance and shunt reactor parameters are designed. Full article

Our previous research demonstrated the health benefits of sericin-derived oligopeptides (SDOs) from yellow silk cocoons, particularly their hypoglycemic and antihypertensive properties. This study aims to produce SDOs at a pilot scale, preparing them for large commercial production as a novel food ingredient, and investigates the impact of scale-up on their characteristics and specifications. We compared the productivity of SDOs generated from 25 L and 300 L batches via the hydrolysis of sericin using 5% Neutrase (E/S) at 50 °C for 4 h. The 300 L production scale outperformed the 25 L scale, achieving a hydrolysis degree (DH) of 8.63%, a solid recovery rate of 94.35%, and enhanced inhibitory actions for dipeptidyl peptidase IV (DPP-IV) and angiotensin-converting enzyme (ACE). The characterization of peptides was carried out in ultrafiltered SDOs. Peptides < 3 kDa demonstrated optimal enzyme inhibition and were then fractionated by size exclusion chromatography into nine distinct fractions. Of the nine fractions, F1, F8, and F9 had significant enzyme inhibitory activity. LC-MS/MS analysis revealed 32 unique peptide sequences, with YPDLPYH exhibiting significant dual inhibitory effects on both DPP-IV (IC₅₀ 1.35 mM) and ACE (IC₅₀ 18.10 μM). The maximum residue limit (MRL) for trace metals, pesticide residues, and microbiological contamination in SDOs complies with food regulations. SDOs exhibited stability at 4, 25, and 45 °C for six months, based on their physical characteristics and biological activity. Considering their investigated characteristics, SDOs could be manufactured at a pilot capacity and used as a functional food component in commercial applications designed to improve metabolic health. Full article

This study optimizes the process conditions for preparing angiotensin-converting enzyme (ACE) inhibitory peptides from skimmed goat milk (SGM) hydrolyzed by multi-enzymes using response surface methodology. When the enzymatic hydrolysis time was 90 min, the optimal hydrolysis conditions were a pH of 8.49, enzyme-to-substrate ratio (E/S ratio) of 8.04%, and temperature of 61.54 °C. The hydrolysis degree and ACE inhibitory activity were 65.39% ± 0.01% and 84.65% ± 0.03%, respectively. After purification by ultrafiltration, macroporous resin, and gel filtration, the ACE inhibitory activity of F2-2 in the two components of F2 was higher, with the ACE inhibitory rate of 93.97% ± 0.15% and IC₅₀ of 0.121 ± 0.004 mg/mL. The content of hydrophobic amino acids, fatty amino acids, and aromatic amino acids in component F2-2 accounts for 73.17%, 33.86%, and 33.72%, respectively. Eleven peptides were isolated and identified from the F2-2 components of the enzymatic hydrolysate of SGM, including two peptides without an established database. The peptides mainly came from β casein, α_S1 casein, and α_S2 casein. Full article

Joint bearings are widely used in modern industry in order to improve the mechanical properties of the outer surface of its inner ring. A laser quenching experiment was carried out in this paper. First of all, an experimental investigation was conducted on GCr15 ball-bearing material utilizing laser quenching, focusing on the effects of laser irradiation angles ranging from 0° to 10° and laser power levels between 600 W and 1100 W on the degree of hardening and microstructural alterations of the bearing material. Additionally, a reliable finite element analysis model was developed to assess the temperature field throughout the process. The findings indicate that an inclined laser enhances the stability of the hardened layer. Specifically, the hardening effect is minimal when the laser power is below 700 W, and optimal hardening is observed at power levels between 800 W and 900 W. During the laser quenching process when the temperature of the bearing material surpasses Ac1, the cooling rate can exceed 1700 °C/s. In regions where the peak temperature exceeds Ac1, the microstructure will undergo refinement, resulting in a reduction in the size of the martensite and a significant decrease in the number of carbides. In addition, the hardness value of these regions can be increased by 6 to 8 HRC, and the thickness of the quenching layer may exceed 0.3 mm. In the temperature range between Ac1 and Ms, the bearing material undergoes tempering, resulting in lower hardness compared to the base material, along with larger martensite and carbide particles. Furthermore, when using the overlap technique during the laser quenching, there will be a tempering zone both inside and on the surface of the bearing; meanwhile, the heat zones generated by different passes of the laser may have partly interacted, and the hardened zone generated by the previous pass may undergo tempering again. Full article

Nandina domestica ‘Firepower’ is one of the most popular colorful foliage species in landscaping. However, it is currently propagated mainly by seeding and cuttings, with a low reproduction coefficient, hindering the cultivation of this species. Therefore, establishing an in vitro regeneration system would be beneficial for the industrialized production of Nandina domestica ‘Firepower’. In this study, an ex vivo regeneration system was established using the direct organogenesis pathway. In early April, the new shoots of Nandina domestica ‘Firepower’ were selected, and the stem segments of 1~2 cm were cut as the disinfection materials for the explants. The optimal formulation for inducing axillary shoots was 1/2 MS + 1.5 mg L⁻¹ 6-benzylaminopurine (BA) + 0.3 mg L⁻¹ indole-3-butric acid (IBA). The optimal formulation for the differentiation and proliferation of axillary shoots was 1/2 MS + 1.5 mg L⁻¹ BA + 0.01 mg L⁻¹ IBA with a multiplicity of proliferation of 9.22. We determined that the rooting of axillary shoots required a combination of IBA, naphthalene acetic acid (NAA), and activated carbon (AC). The optimal formulation for rooting was 1/2 MS + 0.2 mg L⁻¹ NAA + 0.3 mg L⁻¹ IBA + 0.2 mg L⁻¹ AC. After a two-day hardening period for tissue-cultured plantlets, a substrate consisting of peat soil, vermiculite, and perlite at a ratio of 2:2:1 was determined to be the optimal cultivation formulation. This system provides a framework for the industrialized production of Nandina domestica ‘Firepower’. Full article

Viburnum opulus L. ‘Roseum’ is a highly valuable ornamental plant for landscaping, but it has a long propagation cycle and low propagation coefficient. In this study, stem segments with axillary buds from Viburnum opulus L. ‘Roseum’ were used as explants. We systematically analyzed the use of sodium hypochlorite for the sterilization of explants, as well as the effects of different plant growth regulator combinations and concentrations on shoot bud induction, shoot proliferation, the rooting of tissue-cultured shoots, and the transplanting of the tissue-cultured shoots. A complete rapid propagation technology system for Viburnum opulus L. ‘Roseum’ was established. The results showed that a disinfection method using 75% ethanol for 30 s and soaking in 5% sodium hypochlorite for 5 min was the most suitable for disinfecting the stem segments of Viburnum opulus L. ‘Roseum’, which showed low contamination and a 73.33% survival rate. The ideal medium for primary bud induction was WPM (Woody Plant Basal Medium) + 2.0 mg·L⁻¹ 6-benzylaminopurine (6-BA) + 0.15 mg·L⁻¹ indole-3-butyric acid solution (IBA) + 25 g·L⁻¹ sucrose. The optimal medium for shoot proliferation was WPM + 1.0 mg·L⁻¹ 6-BA + 0.15 mg·L⁻¹ IBA + 25 g·L⁻¹ sucrose, achieving an induction rate of 7.17. For the rooting of tissue-cultured shoots, the most suitable formulation was 1/2 WPM + 0.3 mg·L⁻¹ naphthaleneacetic acid (NAA) + 0.3 mg·L⁻¹ activated charcoal (AC) + 25 g·L⁻¹ sucrose, which induced robust and developed root systems. This study provides a technical basis for the establishment of a fast propagation system for the industrial production of Viburnum opulus L. ‘Roseum’. Full article

Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ single crystals (PMN-PT SCs) are widely utilized in high-performance piezoelectric devices due to their exceptional piezoelectric properties. Among the various post-processing techniques for domain engineering in PMN-PT SCs, alternating current polarization (ACP) has become a widely adopted method for enhancing piezoelectric performance. This study proposes a new ultrahigh-temperature field-cooling polarization (UFCP) technique, combining direct current polarization (DCP) and ACP with field cooling above the Curie temperature. Dielectric spectra indicate that the UFCP method promotes electric field-induced phase transitions above the Curie point, forming a stable multiphase configuration. The transverse piezoelectric coefficient d31 of UFCP SCs is 1126pC/N, and the electromechanical coupling factor k31 is 0.559. Compared with traditional DCP, UFCP increases d31 by 68.6%, the mechanical quality factor Qm by 16.7%, and the piezoelectric figure of merit (FOM) by 98.3%. Furthermore, under high-power excitation with a root-mean-square voltage of 15V, UFCP achieves a 343% increase in power and a 130.5% improvement in the FOM compared with DCP, demonstrating its potential for enhancing high-power performance in practical applications. Full article