bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Response Surface Methodology to Design and Optimize Purification of Acetone or Aqueous Acetone Extracts of Hop Cones (Humulus lupulus L.) Using Superparamagnetic Iron Oxide Nanoparticles for Xanthohumol Isolation
Authors: Żuk Natalia , Pasieczna-Patkowska Sylwia , Flieger Jolanta
Published: September 2024

Iron oxide nanoparticles (IONPs) are an ideal sorbent for magnetic dispersion extraction due to their superparamagnetic properties and developed and active surface. This work aims to use IONPs, obtained by chemical co-precipitation, to purify 100% acetone and 50% acetone extracts from hop cones (Humulus lupulus L.) obtained by ultrasonic-assisted solvent extraction. The extracts were purified from bitter acids (i.e., humulones, lupulones) to isolate xanthohumol. The sorption conditions were optimized depending on the composition of the extraction mixture, specifically the mass of IONPs and the time needed to achieve effective sorption using response surface methodology (RSM). An analysis of variance (ANOVA) was performed to assess the adequacy of the developed model, and a good agreement was found between the experimental data and the proposed model. The polynomial equation describing the model is highly significant (p < 0.05), with a precision of Adeq (above 4). This indicates the usefulness of the polynomial regression model for prediction in experimental design. The final products of the purification for 100% acetone extracts and 50% acetone contain 40.58 ± 2.84 µg mL−1 and 57.64 ± 0.83 µg mL−1 of xanthohumol, respectively. The use of 50% acetone extract provides more favorable conditions due to the smaller amount of nanoparticles required for extract purification and a higher recovery of xanthohumol. The development of a reliable multivariate model allowed for the optimization of the extract purification process, resulting in high-purity xanthohumol from natural sources.
Effect of Phosphoric Acid and Soluble Phosphate on the Properties of Magnesium Oxychloride Cement
Authors: Huang Qing , Wang Su , Du Yongsheng , Yin Zhigang , Chen Bing , Zhang Jie , Zheng Weixin
Published: September 2024

This study investigates the effects of phosphoric acid (H3PO4), potassium dihydrogen phosphate (KH2PO4) and sodium dihydrogen phosphate (NaH2PO4) admixtures on the setting time, compressive strength and water resistance of magnesium oxychloride cement (MOC). MOC samples incorporating different admixtures are prepared, and their hydration products and microstructures are studied via X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that the addition of H3PO4, KH2PO4 and NaH2PO4 reduces the initial and final setting times and decreases the compressive strength. However, the compressive strength of MOC is higher than 30.00 MPa with the addition of 2.0 wt.% phosphoric acid and its phosphate after 14 days of air curing. The water resistance of modified MOC slurries is significantly improved. The softening coefficient of MOC with 2.0 wt.% H3PO4 is 1.2 after 14 days of water immersion, which is 3.44 times higher than that of the neat MOC. The enhancement in water resistance is attributed to the formation of amorphous gel facilitated by H3PO4, KH2PO4 and NaH2PO4. Furthermore, the improvement in water resistance is manifested as H3PO4 > KH2PO4 > NaH2PO4.
Curriculum Design and Sim2Real Transfer for Reinforcement Learning in Robotic Dual-Arm Assembly
Authors: Wrede Konstantin , Zarnack Sebastian , Lange Robert , Donath Oliver , Wohlfahrt Tommy , Feldmann Ute
Published: September 2024

Robotic systems are crucial in modern manufacturing. Complex assembly tasks require the collaboration of multiple robots. Their orchestration is challenging due to tight tolerances and precision requirements. In this work, we set up two Franka Panda robots performing a peg-in-hole insertion task of 1 mm clearance. We structure the control system hierarchically, planning the robots’ feedback-based trajectories with a central policy trained with reinforcement learning. These trajectories are executed by a low-level impedance controller on each robot. To enhance training convergence, we use reverse curriculum learning, novel for such a two-armed control task, iteratively structured with a minimum requirements and fine-tuning phase. We incorporate domain randomization, varying initial joint configurations of the task for generalization of the applicability. After training, we test the system in a simulation, discovering the impact of curriculum parameters on the emerging process time and its variance. Finally, we transfer the trained model to the real-world, resulting in a small decrease in task duration. Comparing our approach to classical path planning and control shows a decrease in process time, but higher robustness towards calibration errors.
Configuration and Parameter Optimization Design of a Novel RBR-2RRR Spherical Hybrid Bionic Shoulder Joint
Authors: Shi Shuyang , Wang Fengxin , Zhou Yulin
Published: September 2024

To improve the workspace, linear displacement stiffness, and driving torque utilization of humanoid robot shoulder joint mechanisms, an offset-designed RBR-2RRR (R represents the revolute pair, and B represents the ball cage joint) spherical hybrid bionic shoulder joint configuration (SHBSJC) is proposed and its structural parameters are optimized. Firstly, the shoulder joint’s physiological structure is biomimetically designed, a prototype mechanism of RBR-2RRR SHBSJC is proposed, and its kinematics are solved. The deformation response of RBR-2RRR and 3-RRR under the same load is compared to verify the obtained configuration can improve the linear displacement stiffness. Considering the workspace and singularity, using the GCI and GDCI as optimization functions, the recommended and adopted values of structural parameters are obtained. The distribution diagrams of the LCI and LDCI demonstrate that the configuration meets performance expectations. To further increase the prototype mechanism’s workspace and match the human shoulder joint’s motion range, an offset-designed RBR-2RRR SHBSJC is proposed, and the offset angle, installation posture angle, and spatial mapping relationship of the mechanism are determined. The results of workspace comparison and virtual model machine action simulation indicate that the final configuration meets the workspace expectations. This work enriches the shoulder joint configuration types and has engineering application value.
Test Stand for Microjet Engine Prototypes
Authors: Tărăbîc Cornel Mihai , Cican Grigore , Olariu Cristian , Dediu Gabriel , Catană Răzvan Marius
Published: September 2024

To investigate the functionality and performance of a prototype microjet engine, we constructed a versatile test stand tailored to the specifications of a 400 N prototype. This test stand facilitated a comprehensive study by enabling real-time recording of 45 essential parameters for analysis, encompassing temperatures, pressures, speed, fuel flow, thrust, vibration, and various other monitored metrics. All parameters and control elements were seamlessly integrated via a data acquisition and control system, utilizing a compactDAQ (Data Acquisition) system from National Instruments and a custom Virtual Instrument programmed with graphical language. The test stand offers both manual and automated operation modes, with the flexibility for hybrid operation. For instance, following the idle regime, manual control using a potentiometer can seamlessly transition from automated control via a proportional control (P control) mechanism. Before the experimental campaign, rigorous verification and validation tests were conducted to ensure the reliability and accuracy of the setup. The experimental campaign comprised a series of manual tests focusing on the fuel system and automated tests covering starting, idle, working, and stopping regimes. This structured approach allowed for a comprehensive evaluation across different operational scenarios, providing insights into the engine’s behavior and performance under varying conditions.
Magnetohydrodynamic Analysis and Fast Calculation for Fractional Maxwell Fluid with Adjusted Dynamic Viscosity
Authors: Liu Yi , Jiang Mochen
Published: September 2024

From the perspective of magnetohydrodynamics (MHD), the heat transfer properties of Maxwell fluids under MHD conditions with modified dynamic viscosity present complex challenges in numerical simulations. In this paper, we develop a time-fractional coupled model to characterize the heat transfer and MHD flow of Maxwell fluid with consideration of the Hall effect and Joule heating effect and incorporating a modified dynamic viscosity. The fractional coupled model is numerically solved based on the L1-algorithm and the spectral collocation method. We introduce a novel approach that integrates advanced algorithms with a fully discrete scheme, focusing particularly on the computational cost. Leveraging this approach, we aim to significantly enhance computational efficiency while ensuring accurate representation of the underlying physics. Through comprehensive numerical experiments, we explain the thermodynamic behavior in the MHD flow process and extensively examine the impact of various critical parameters on both MHD flow and heat transfer. We establish an analytical framework for the MHD flow and heat transfer processes, further investigate the influence of magnetic fields on heat transfer processes, and elucidate the mechanical behavior of fractional Maxwell fluids.
Facile Synthesis of Core-Shell Magnetic Iron Oxide@SiO2-NH2 Nanoparticles and Their Application in Rapid Boron Removal from Aqueous Solutions
Authors: Hu Qinqin , Zhang Manman , Peng Jiaoyu , Dong Yaping , Li Wu , Meng Lingzong
Published: September 2024

In this study, amino-functionalized magnetic particles (iron oxide@SiO2-NH2) with core-shell structures were synthesized and evaluated for rapid boron removal from aqueous solutions. The results showed that the specific surface area of the iron oxide@SiO2-NH2 (131.24 m2⋅g−1) increased greatly compared to pure iron oxide (30.98 m2⋅g−1). The adsorption equilibrium was less than 2 h, with an adsorption capacity of 29.76 mg⋅g−1 at pH = 6 at 15 °C. The quasi-second-order kinetic model described the boron adsorption process well, and both the Langmuir and Freundlich models were suitable for characterizing the adsorption isotherms. The zeta potential and XPS analysis before and after adsorption revealed that the main adsorption mechanism was the hydrogen bonding formation between the terminal -NH2 groups of the adsorbent and the boric acid. In addition, the adsorbent still maintained a high adsorption performance after five adsorption–desorption cycles, which illustrated that the iron oxide@SiO2-NH2 may be a potential adsorbent for environmental boron removal treatment.
Meshless Error Recovery Parametric Investigation in Incompressible Elastic Finite Element Analysis
Authors: Althaqafi Essam , Singh Devinder , Ahmed Mohd
Published: September 2024

The meshless displacement error-recovery parametric investigation in finite element method-based incompressible elastic analysis is presented in this study. It investigates key parameters such as interpolation schemes, patch configurations, dilation indexes, weight functions, and meshing patterns. The study evaluates error recovery effectiveness (local and global), convergence rates, and adaptive mesh improvement for triangular/quadrilateral discretization schemes. It uses meshless moving least squares (MLS) interpolation with rectangular and circular support regions and solves benchmark plate and cylinder problems. It is observed that a circular influence region, a cubic spline weight function, and regular mesh patterns yield a better performance of than an MLS-based error recovery method. The study also concludes that lower dilation index values with rectangular influence regions are preferable for regular meshes, while higher dilation index values with radial influence regions are suitable for preferable meshes to enhance MLS error recovery.
Unraveling the Omega-3 Puzzle: Navigating Challenges and Innovations for Bone Health and Healthy Aging
Authors: Ali Zayana , Al-Ghouti Mohammad Ahmed , Abou-Saleh Haissam , Rahman Md Mizanur
Published: September 2024

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs, n-3 PUFAs), including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), are essential polyunsaturated fats primarily obtained from fatty fish and plant-based sources. Compelling evidence from preclinical and epidemiological studies consistently suggests beneficial effects of ω-3 PUFAs on bone health and healthy aging processes. However, clinical trials have yielded mixed results, with some failing to replicate these benefits seen in preclinical models. This contraindication is mainly due to challenges such as low bioavailability, potential adverse effects with higher doses, and susceptibility to oxidation of ω-3 fatty acids, hindering their clinical effectiveness. This review comprehensively discusses recent findings from a clinical perspective, along with preclinical and epidemiological studies, emphasizing the role of ω-3 PUFAs in promoting bone health and supporting healthy aging. Additionally, it explores strategies to improve ω-3 PUFA efficacy, including nanoparticle encapsulation and incorporation of specialized pro-resolving mediators (SPM) derived from DHA and EPA, to mitigate oxidation and enhance solubility, thereby improving therapeutic potential. By consolidating evidence from various studies, this review underscores current insights and future directions in leveraging ω-3 PUFAs for therapeutic applications.
A Review of Sponge-Derived Diterpenes: 2009–2022
Authors: Xia Jinmei , Chen Xiangwei , Li Guangyu , Qiu Peng , Wang Weiyi , Shao Zongze
Published: September 2024

Sponges are a vital source of pharmaceutically active secondary metabolites, of which the main structural types are alkaloids and terpenoids. Many of these compounds exhibit biological activities. Focusing specifically on diterpenoids, this article reviews the structures and biological activities of 228 diterpenes isolated from more than 33 genera of sponges from 2009 to 2022. The Spongia sponges produce the most diterpenoid molecules among all genera, accounting for 27%. Of the 228 molecules, 110 exhibit cytotoxic, antibacterial, antifungal, antiparasitic, anti-inflammatory, and antifouling activities, among others. The most prevalent activity is cytotoxicity, present in 54 molecules, which represent 24% of the diterpenes reported. These structurally and biologically diverse diterpenoids highlight the vast, yet largely untapped, potential of marine sponges in the discovery of new bioactive molecules for medicinal use.
Innovative Trends in Modified Membranes: A Mini Review of Applications and Challenges in the Food Sector
Authors: do Nascimento Nicole Novelli , Paraíso Carolina Moser , Molina Luiza C. A. , Dzyazko Yuliya S. , Bergamasco Rosângela , Vieira Angélica Marquetotti Salcedo
Published: September 2024

Membrane technologies play a pivotal role in various industrial sectors, including food processing. Membranes act as barriers, selectively allowing the passage of one or other types of species. The separation processes that involve them offer advantages such as continuity, energy efficiency, compactness of devices, operational simplicity, and minimal consumption of chemical reagents. The efficiency of membrane separation depends on various factors, such as morphology, composition, and process parameters. Fouling, a significant limitation in membrane processes, leads to a decline in performance over time. Anti-fouling strategies involve adjustments to process parameters or direct modifications to the membrane, aiming to enhance efficiency. Recent research has focused on mitigating fouling, particularly in the food industry, where complex organic streams pose challenges. Membrane processes address consumer demands for natural and healthy products, contributing to new formulations with antioxidant properties. These trends align with environmental concerns, emphasizing sustainable practices. Despite numerous works on membrane modification, a research gap exists, especially with regard to the application of modified membranes in the food industry. This review aims to systematize information on modified membranes, providing insights into their practical application. This comprehensive overview covers membrane modification methods, fouling mechanisms, and distinct applications in the food sector. This study highlights the potential of modified membranes for specific tasks in the food industry and encourages further research in this promising field.
Based on Sportomics: Comparison of Physiological Status of Collegiate Sprinters in Different Pre-Competition Preparation Periods
Authors: Fu Pengyu , Duan Xiaomin , Zhang Yuting , Dou Xiangya , Gong Lijing
Published: September 2024

This study aimed to assess the impact of pre-competition training by comparing the differences of collegiate sprinters in physiological state between strengthening and tapering training period by sportomics and combining their sport performance. Fifteen collegiate sprinters were investigated or tested on their body composition, dietary habits, energy expenditure, sleep efficiency, heart rate and respiratory rate during training, blood (blood cells, biochemical and immune markers) and urine (urinalysis), gut microbiome distribution, microbiome and blood metabolites, and their functions during the strengthening (Group A) and tapering training period (Group B) prior to competing in the national competitions. We found that 26.67% of sprinters achieved personal bests (PB) after the competition. The limb skeletal muscle mass and lymphocyte ratio of male sprinters in Group B were lower than those in Group A, and the serum creatine kinase (CK) level was higher than Group A (p < 0.05). The levels of serum CK, interleukin-6 (IL-6), interleukin-1β (IL-1β), and urine-specific gravity (SG) of the two groups were higher than the upper limit of the reference value. The detection rates of urine white blood cell (WBC) and protein in Group B were higher than those in Group A. The gut microbiome health index (GMHI) of Group A was higher than that of Group B, and the microbial dysbiosis index was lower than that of Group B. The ratio of Firmicutes/Bacteroidota (F/B) in Group A was higher than that in Group B. There were 65 differential metabolites in the A/B group, and the enriched pathway was mainly the NF-kappa B signaling pathway (up); B/T cell receptor signaling pathway (up); Th1 and Th2 cell differentiation (up); phenylalanine metabolism (up); and growth hormone synthesis, secretion, and action (up). There were significant differences in blood metabolites between the A and B groups, with a total of 89 differential metabolites, and the enriched pathway was mainly the NF-kappa B signaling pathway (up), T cell receptor signaling pathway (up), Th1 and Th2 cell differentiation (up), and glycerophospholipid metabolism (down). In conclusion, the imbalance of the gut microbiome and inflammation and immune-related metabolites of collegiate sprinters during the pre-competition tapering training period may be the cause of their limited sports performance.
Improved DC and RF Characteristics of GaN-Based Double-Channel HEMTs by Ultra-Thin AlN Back Barrier Layer
Authors: Yu Qian , Shi Chunzhou , Yang Ling , Lu Hao , Zhang Meng , Zou Xu , Wu Mei , Hou Bin , Gao Wenze , Wu Sheng , Ma Xiaohua , Hao Yue
Published: September 2024

In order to improve the off-state and breakdown characteristics of double-channel GaN HEMTs, an ultra-thin barrier layer was chosen as the second barrier layer. The strongly polarized and ultra-thin AlN sub-barrier and the InAlN sub-barrier are great candidates. In this article, the two epitaxial structures, AlGaN/GaN/AlN/GaN (sub-AlN) HEMTs and AlGaN/GaN/InAlN/GaN (sub-InAlN) HEMTs, were compared to select a more suitable sub-barrier layer. Through TEM images of the InAlN barrier layer, the segregation of In components can be seen, which decreases the mobility of the second channel. Thus, the sub-AlN HEMTs have a higher output current density and transconductance than those of the sub-InAlN HEMTs. Because the high-quality AlN barrier layer shields the gate leakage current, a 294 V breakdown voltage was achieved by the sub-AlN HEMTs, which is higher than the 121 V of the sub-InAlN HEMTs. The current gain cut-off frequency (fT) and maximum oscillation frequency (fmax) of the sub-AlN HEMTs are higher than that of the sub-InAlN HEMTs from low to high bias voltage. The power-added efficiency (PAE) and output power density (Pout) of the sub-AlN HEMTs are 57% and 11.3 W/mm at 3.6 GHz and 50 V of drain voltage (Vd), respectively. For the sub-InAlN HEMTs, the PAE and Pout are 41.4% and 8.69 W/mm, because of the worse drain lag ratio. Thus, the Pout of the sub-AlN HEMTs is higher than that of the sub-InAlN HEMTs.
A Pressure Sensor Based on the Interaction between a Hard Magnet Magnetorheological Elastomer and a Hall Effect Structure
Authors: Sul Onejae , Choo Sung Joong , Jee In-Sik , Kim Jeengi , Kim Hyeong-Jun
Published: September 2024

In this article, we report a novel pressure sensing method based on the Hall effect and a hard magnet magnetorheological elastomer (hmMRE). The elastic property of the MRE under pressure was used to generate spatial variation in the magnetic flux density around the MRE, and the variation was detected by the Hall effect device underneath. As the first development in this kind of pressure sensing mechanism, we conducted research for the following three purposes: (1) to verify the Hall effect on the output signal, (2) to understand the sensor output variations under different modes of operation, and (3) to utilize the mechanism as a pressure sensor. We characterized the sensor with its operation parameters, such as signal polarity switching depending on wiring directions, signal amplitude, and offset shift depending on the input voltage. Based on the analyses, we concluded that the Hall voltage represents the pressure applied on the hmMRE, and the new pressure sensing mechanism was devised successfully.
A Novel Sensing Method to Detect Malachite Green Contaminant on Silicon Substrate Using Nonlinear Optics
Authors: Ahyad Muhammad , Hardhienata Hendradi , Hasdeo Eddwi Hesky , Wella Sasfan Arman , Handayasari Faridah , Alatas Husin , Birowosuto Muhammad Danang
Published: September 2024

We propose a nonlinear-optics-based nanosensor to detect malachite green (MG) contaminants on semiconductor interfaces such as silicon (Si). Applying the simplified bond hyperpolarizability model (SBHM), we simplified the second-harmonic generation (SHG) analysis of an MG-Si(111) surface and were able to validate our model by reproducing experimental rotational anisotropy (RA) SHG experiments. For the first time, density functional theory (DFT) calculations using ultrasoft pseudopotentials were implemented to obtain the molecular configuration and bond vector orientation required by the SBHM to investigate and predict the second-harmonic generation contribution for an MG-Si 001 surface. We show that the SBHM model significantly reduces the number of independent components in the nonlinear tensor of the MG-Si(111) interface, opening up the possibility for real-time and non-destructive contaminant detection at the nanoscale. In addition, we derive an explicit formula for the SHG far field, demonstrating its applicability for various input polarization angles. Finally, an RASHG signal can be enhanced through a simulated photonic crystal cavity up to 4000 times for more sensitivity of detection. Our work can stimulate more exploration using nonlinear optical methods to detect and analyze surface-bound contaminants, which is beneficial for environmental monitoring, especially for mitigating pollution from textile dyes, and underscores the role of nonlinear optics in real-time ambient-condition applications.
Fabrication of Electrospun Porous TiO2 Dielectric Film in a Ti–TiO2–Si Heterostructure for Metal–Insulator–Semiconductor Capacitors
Authors: Yoo Jin-Uk , Choi Tae-Min , Pyo Sung-Gyu
Published: September 2024

The development of metal–insulator–semiconductor (MIS) capacitors requires device miniaturization and excellent electrical properties. Traditional SiO2 gate dielectrics have reached their physical limits. In this context, high-k materials such as TiO2 are emerging as promising alternatives to SiO2. However, the deposition of dielectric layers in MIS capacitors typically requires high-vacuum equipment and challenging processing conditions. Therefore, in this study, we present a new method to effectively fabricate a poly(vinylidene fluoride) (PVDF)-based TiO2 dielectric layer via electrospinning. Nano-microscale layers were formed via electrospinning by applying a high voltage to a polymer solution, and electrical properties were analyzed as a function of the TiO2 crystalline phase and residual amount of PVDF at different annealing temperatures. Improved electrical properties were observed with increasing TiO2 anatase content, and the residual amount of PVDF decreased with increasing annealing temperature. The sample annealed at 600 °C showed a lower leakage current than those annealed at 300 and 450 °C, with a leakage current density of 7.5 × 10−13 A/cm2 when Vg = 0 V. Thus, electrospinning-based coating is a cost-effective method to fabricate dielectric thin films. Further studies will show that it is flexible and dielectric tunable, thus contributing to improve the performance of next-generation electronic devices.
A Comparison of Growth Performance, Blood Parameters, Rumen Fermentation, and Bacterial Community of Tibetan Sheep When Fattened by Pasture Grazing versus Stall Feeding
Authors: Ji Huiying , Chen Lili , Ma Yi , Degen Abraham Allan , Yuan Zhengrong , Chen Hualong , Zhou Jianwei
Published: September 2024

Traditionally, Tibetan sheep only graze pastures without any supplementary feed. However, in recent years, feedlots are being used for fattening Tibetan sheep. The present study compared the growth rates, blood parameters, rumen fermentation, and bacterial communities in Tibetan sheep fattened by pasture grazing (PG) versus those fattened by stall feeding (SF). Twenty 18-month-old Tibetan sheep wethers (42.6 ± 2.11 kg) were divided randomly into PG (n = 10) and SF (n = 10) groups. The PG sheep grazed the grasslands without any supplementary feed, while the SF sheep were offered a commercial total mixed ration (TMR) at a crude protein content of 16.2% DM and an ME of 10.59 MJ/kg. The sheep were on their treatments for 70 days, which included 10 days for adaptation and 60 days for measurements. The average daily gain, white blood cell and lymphocyte counts were greater (p < 0.05), while the platelet count was lower (p < 0.05) in the SF group than in the PG group. The serum glutathione peroxidase activity, and concentrations of total proteins and albumin were greater (p < 0.05), while glucose was lower (p < 0.01) in the PG group compared to the SF group. The concentrations of ruminal ammonia–N and total volatile fatty acids (VFAs) were greater (p < 0.05), while the pH was lower (p < 0.05) in the SF group compared to the PG group. The molar proportion of acetate and the ratio of acetate to propionate were greater (p < 0.01) in the PG sheep than in the SF sheep, but the molar proportion of propionate and iso-VFAs did not differ (p > 0.05) between the groups. Based on the PCoA, the ruminal bacterial communities were distinct between groups, and the alpha diversity was greater (p < 0.001) in the PG sheep than in the SF sheep. The dominant phyla of the rumen bacteria were Firmicutes and Bacteroidetes, while the Firmicutes to Bacteroidetes ratio was greater (p < 0.001) in the SF group than in the PG group. At the genus level, the relative abundance of Ruminococcus was greater (p < 0.05) in the SF group, while the abundances of Prevotella, the Rikenellaceae_RC9_gut_group, Butyrivibrio, and unclassified_f_Lachnospiraceae were greater (p < 0.05) in the PG group. It was concluded that the Tibetan sheep adopted a short-term intensive fattening strategy when stall fed which altered the rumen bacterial community and blood parameters, enhanced rumen fermentation, and, ultimately, improved their average daily gain.
Mediterranean Diet Effect on the Intestinal Microbiota, Symptoms, and Markers in Patients with Functional Gastrointestinal Disorders
Authors: Garicano Vilar Elena , López Oliva Sara , Penadés Bruno F. , Sánchez Niño Guerthy Melissa , Terrén Lora Ana , Sanz Rojo Sara , Mauro Martín Ismael San
Published: September 2024

The Mediterranean diet (MD) has beneficial effects on the intestinal microbiota by the promotion of bacteria associated with a healthy gut. However, its impact on intestinal fungi, among others, is still unknown, and how it affects digestive symptoms and different biomarkers in patients with gastrointestinal (GI) disorders has hardly been explored. The present study evaluated the effect of the MD on gut microbial diversity and structure and intestinal symptoms and biomarkers after 6 weeks of dietary intervention in 46 patients with GI disorders. Dysbiosis in fungal composition and diversity was observed, with a significantly lower abundance of Sordariomycetes, Leotiomycetes, and Orbiliomycetes; a significantly higher abundance of Saccharomycetes; the Chytridiomycota and Mucoromycota phyla were significantly reduced; and the bacterial microbiota remained unchanged. In addition, various GI disorders decreased and associations between stool consistency and intestinal permeability were found with the bacterial genera Alistipes and Roseburia. Thus, the data suggest that MD can alter the fungal intestinal microbiota and improve GI disorders.
Garlic-Induced Enhancement of Bifidobacterium: Enterotype-Specific Modulation of Gut Microbiota and Probiotic Populations
Authors: Ha Jina , Kim Jinwoo , Kim Seongok , Lee Kwang Jun , Shin Hakdong
Published: September 2024

The gut microbiome is a dynamic ecosystem crucial for maintaining its host’s health by regulating various immune and metabolic functions. Since diet plays a fundamental role in shaping the gut microbiome, understanding the relationship between food consumption and microbiome structure is essential. Although medicinal plants are widely recognized for their broad health benefits, their specific impact on the gut microbiome remains unclear. In this study, we investigated the effects of garlic (Allium sativum) on the gut microbiome using an in vitro human fecal incubation model. Our findings revealed that the impact of garlic on gut microbial structure varied depending on the dominant gut microbiome components (enterotypes). The Bacteroides-dominant enterotype exhibited significant changes in overall microbial diversity in response to garlic, while the Prevotella-dominant enterotype remained unaffected. Additionally, the garlic treatment led to specific alterations in microbiota composition, such as an increase in beneficial probiotics like Bifidobacterium. We validated garlic’s prebiotic potential by promoting the growth of Bifidobacterium adolescentis under in vitro culture conditions. Our study highlights the importance of understanding enterotype-specific responses to diet and suggests that garlic may serve as a dietary supplement for modulating gut microbiota and promoting the growth of beneficial probiotics.
Enrichment Mechanism of Polymetallic Elements at the Base of the Niutitang Formation in Southeast Chongqing
Authors: Wang Guozhi , Zhang Can , Liu Dayong , Qiu Linfei , Li Ziying , Peng Ping’an
Published: September 2024

Polymetallic enrichment layers are commonly found at the base of the Lower Cambrian and extensively distributed across the Upper Yangtze Platform, yet their genetic models remain controversial. This study systematically collected samples from a typical section in the southeastern Chongqing region for mineral, organic, and inorganic analyses. It investigates the relationship between the abundance of various trace metal elements and organic matter at the base of the Niutitang Formation, as well as the vertical distribution characteristics of organic carbon isotopes and organic matter features. The results indicate that the Niutitang Formation shale exhibits a distinct three-part structure from bottom to top. Various metal elements are enriched in the lower interval, showing a close correlation between the abundance of polymetallic elements and the carbon isotopes of shale organic matter. The middle interval contains the highest TOC value and the lowest Ti/Al ratio, while the upper interval shows a significant decrease in organic matter abundance, with a clear positive correlation between the excess silicon content and Ti/Al ratio. Additionally, the mixing effect of deep-sea upwelling is the primary control on the formation of polymetallic enrichment layers in the lower interval, followed by the adsorption of organic matter under anoxic conditions. The sedimentary environment of the upper interval of the Niutitang Formation trends toward oxidation, with paleoclimate shifting toward colder and drier conditions, exhibiting aeolian sedimentary features that are unfavorable for the enrichment of trace metal elements. Consequently, upwelling is a key factor in the enrichment and mineralization of trace metal elements at the base of the Lower Cambrian in the Upper Yangtze region.
First U-Pb (CA-ID-TIMS) Dating of the Uppermost Permian Coal Interval in the Minusinsk Coal Basin (Siberia, Russia) Using Zircon Grains from Volcanic Ashfalls
Authors: Silantiev Vladimir V. , Arbuzov Sergey I. , Tichomirowa Marion , Käßner Alexandra , Izmailova Alsu Kh. , Ilenok Sergey S. , Soktoev Bulat R. , Nurgalieva Nouria G. , Gutak Yaroslav M. , Felker Anastasia S. , Porokhovnichenko Lyubov G. , Eliseev Nikolai A. , Zharinova Veronika V. , Nurieva Evgenia M. , Urazaeva Milyausha N.
Published: September 2024

This study presents the first U-Pb (CA-ID-TIMS) radioisotopic dating of zircon grains extracted from tonsteins within the uppermost Permian coal interval of the Minusinsk Coal Basin (Siberia, Russia). Petrographic, structural, and mineralogical analyses confirm the volcanic ash origin of the tonsteins. The parent pyroclastic materials are identified as rhyolite–pantellerite for tonstein I-22 and dacite–rhyodacite for tonstein I-12. Morphological analysis of zircon crystals, along with cathodoluminescence and melt inclusion studies, confirms their volcanic origin and crystallisation temperatures of 700–900 °C. New radioisotopic dates of 261.4 ± 0.7 Ma and 261.3 ± 0.4 Ma clarify the age of the Izykh Formation, enabling its direct correlation with the Capitanian Stage of the International Chronostratigraphic Chart. The results emphasise the possible discontinuity of the coal-bearing succession of Siberian palaeocontinent and highlight the potential for further stratigraphic refinement through continued radioisotopic dating of tonsteins.
3D Geological Modeling and Metallogenic Prediction of Kamust Sandstone-Type Uranium Deposit in the Eastern Junggar Basin, NW China
Authors: Geng Yingying , Liu Zhangyue , He Zhongbo , Zhu Pengfei , Huang Shaohua , Ji Huali
Published: September 2024

Sandstone-type uranium deposits hold significant value and promise within China’s uranium resource portfolio, with the majority of these deposits found at the junctions of basins and mountains within Mesozoic and Cenozoic basins. The Kamust uranium mining area, located in the eastern part of the Junggar Basin, represents a significant recent discovery. Prior research on this deposit has been confined to two-dimensional analyses, which pose limitations for a comprehensive understanding of the deposit’s three-dimensional characteristics. To address the issue of uranium resource reserve expansion, this study employs 3D geological modeling and visualization techniques, guided by uranium deposit models and mineral prediction methods. First, a 3D model database of the Kamust uranium deposit was constructed, comprising drill holes, uranium ore bodies, ore-controlling structures, interlayer oxidation zones, and provenance areas. This model enables a transparent and visual representation of the spatial distribution of favorable mineralization horizons, structures, stratigraphy, and other predictive elements in the mining area. Second, based on the three-dimensional geological model, a mineral prediction model was established by summarizing the regional mineralization mechanisms, ore-controlling factors, and exploration indicators. Combined with big-data technology, this approach facilitated the quantitative analysis and extraction of ore-controlling factors, providing data support for the three-dimensional quantitative prediction of deep mineralization in the Kamust uranium deposit. Finally, using three-dimensional weights of evidence and three-dimensional information-quantity methods, comprehensive information analysis and quantitative prediction of deep mineralization were conducted. One prospective area was quantitatively delineated, located east of the Kalasay monocline, which has been well-validated in geological understanding. The research indicates that the area east of the Kalasay monocline in the Kamust mining district has significant exploration potential.
Optoelectronic Properties of Triply Twisted Möbius Carbon Nanobelt and the Design of Its Isomeric Nanomaterials
Authors: Yao Cailian , Wang Tao
Published: September 2024

The triply twisted Möbius carbon nanobelt (TMCNB) possesses an extremely distinctive geometric and electronic structure and therefore is anticipated to demonstrate outstanding optical properties. In this paper, through integrating quantum chemical calculations and wave function analysis approaches, in-depth studies are conducted on the one-photon absorption (OPA) and two-photon absorption (TPA) characteristics, aromaticity, and circular dichroism of the TMCNB. Inspired by this structure, we further deform it to construct a novel structure, MCNB2, and verify the stability of this structure, thereby confirming its rationality. Since variations in structure will result in dissimilar optical properties, we also undertake theoretical analyses on the absorption properties and circular dichroism of MCNB2. The outcomes of this study offer a significant theoretical foundation for the design and construction of chiral optoelectronic materials.
Efficient Production of Some Bioactive Depsides and Simple Phenolic Acids by Microshoots of Aronia × Prunifolia (Purple Aronia) Agitated Cultures as the Result of Feeding Strategy with Four Different Biogenetic Precursors
Authors: Kubica Paweł , Szopa Agnieszka , Setkiewicz Adam , Ekiert Halina
Published: September 2024

A precursor feeding strategy was used for the first time in agitated microshoot cultures of Aronia × prunifolia. This strategy involved the addition of biogenetic precursors of simple phenolic acids (phenylalanine, cinnamic acid, and benzoic acid) and depsides (caffeic acid) into the culture media, with an assessment of its effect on the production of these bioactive compounds. The in vitro cultures were maintained in Murashige–Skoog medium (1 mg/L BAP and 1 mg/L NAA). Precursors at five concentrations (0.1, 0.5, 1.0, 5.0, and 10.0 mmol/L) were fed into the medium at the time of culture initiation (point “0”) and independently on the 10th day of growth cycles. The contents of 23 compounds were determined in methanolic extracts of biomass collected after 20 days of growth cycles using an HPLC method. All extracts contained the same four depsides (chlorogenic, neochlorogenic, rosmarinic, and cryptochlorogenic acids) and the same four simple phenolic acids (protocatechuic, vanillic, caffeic, and syringic acids). Chlorogenic and neochlorogenic acids were the predominant compounds in all extracts (max. 388.39 and 263.54 mg/100 g d.w.). The maximal total contents of all compounds were confirmed after feeding with cinnamic acid (5 mmol/L, point “0”) and caffeic acid (10 mmol/L, point “0”), which caused a 2.68-fold and 2.49-fold increase in the contents of the estimated compounds vs. control cultures (603.03 and 558.48 mg/100 g d.w., respectively). The obtained results documented the efficacy of the precursor feeding strategy in enhancing the production of bioactive compounds in agitated cultures of A. × prunifolia and suggest a potential practical application value.
Organic and Metal–Organic Polymer-Based Catalysts—Enfant Terrible Companions or Good Assistants?
Authors: Králik Milan , Koóš Peter , Markovič Martin , Lopatka Pavol
Published: September 2024

This overview provides insights into organic and metal–organic polymer (OMOP) catalysts aimed at processes carried out in the liquid phase. Various types of polymers are discussed, including vinyl (various functional poly(styrene-co-divinylbenzene) and perfluorinated functionalized hydrocarbons, e.g., Nafion), condensation (polyesters, -amides, -anilines, -imides), and additional (polyurethanes, and polyureas, polybenzimidazoles, polyporphyrins), prepared from organometal monomers. Covalent organic frameworks (COFs), metal–organic frameworks (MOFs), and their composites represent a significant class of OMOP catalysts. Following this, the preparation, characterization, and application of dispersed metal catalysts are discussed. Key catalytic processes such as alkylation—used in large-scale applications like the production of alkyl-tert-butyl ether and bisphenol A—as well as reduction, oxidation, and other reactions, are highlighted. The versatile properties of COFs and MOFs, including well-defined nanometer-scale pores, large surface areas, and excellent chemisorption capabilities, make them highly promising for chemical, electrochemical, and photocatalytic applications. Particular emphasis is placed on their potential for CO2 treatment. However, a notable drawback of COF- and MOF-based catalysts is their relatively low stability in both alkaline and acidic environments, as well as their high cost. A special part is devoted to deactivation and the disposal of the used/deactivated catalysts, emphasizing the importance of separating heavy metals from catalysts. The conclusion provides guidance on selecting and developing OMOP-based catalysts.
Carbon-Supported Fe-Based Catalyst for Thermal-Catalytic CO2 Hydrogenation into C2+ Alcohols: The Effect of Carbon Support Porosity on Catalytic Performance
Authors: Chen Yongjie , Jiang Lei , Lin Simin , Dong Pei , Fu Xiaoli , Wang Yang , Liu Qiang , Wu Mingbo
Published: September 2024

Carbon materials supported Fe-based catalysts possess great potential for the thermal-catalytic hydrogenation of CO2 into valuable chemicals, such as alkenes and oxygenates, due to the excellent active sites’ accessibility, appropriate interaction between the active site and carbon support, as well as the excellent capacities in C-O bond activation and C-C bond coupling. Even though tremendous progress has been made to boost the CO2 hydrogenation performance of carbon-supported Fe-based catalysts, e.g., additives modification, the choice of different carbon materials (graphene or carbon nanotubes), electronic property tailoring, etc., the effect of carbon support porosity on the evolution of Fe-based active sites and the corresponding catalytic performance has been rarely investigated. Herein, a series of porous carbon samples with different porosities are obtained by the K2CO3 activation of petroleum pitch under different temperatures. Fe-based active sites and the alkali promoter Na are anchored on the porous carbon to study the effect of carbon support porosity on the physicochemical properties of Fe-based active sites and CO2 hydrogenation performance. Multiple characterizations clarify that the bigger meso/macro-pores in the carbon support are beneficial for the formation of the Fe5C2 crystal phase for C-C bond coupling, therefore boosting the synthesis of C2+ chemicals, especially C2+ alcohols (C2+OH), while the limited micro-pores are unfavorable for C2+ chemicals synthesis owing to the sluggish crystal phase evolution and reactants’ inaccessibility. We wish our work could enrich the horizon for the rational design of highly efficient carbon-supported Fe-based catalysts.
Polyphosphoric Acid-Promoted Efficient Synthesis of Cinnamides via Aldol Condensation of Amide
Authors: Wang Enhua , Yang Lishou , He Lanfeng , Yang Qian , Wang Xue , Liu Yunlu , Li Manxiang , Lei Yang , Yang Xiaosheng
Published: September 2024

Cinnamides are common core structures that exist in a great number of pharmaceuticals and natural products. The development of efficient methods for preparing cinnamides is in great need. We report herein an efficient polyphosphoric acid (PPA)-promoted direct aldol condensation of an amide for the convenient and straightforward preparation of cinnamides. A variety of cinnamides were obtained in moderate-to-excellent yields (65–89%). This strategy features the use of equivalent amides and a short reaction time.
Rational Design of ZnO/Sc2CF2 Heterostructure with Tunable Electronic Structure for Water Splitting: A First-Principles Study
Authors: Tang Yong , Lu Yidan , Ma Benyuan , Song Jun , Bai Liuyang , Wang Yinling , Chen Yuanyuan , Liu Meiping
Published: September 2024

Heterostructures are highly promising photocatalyst candidates for water splitting due to their advanced properties than those of pristine components. The ZnO/Sc2CF2 heterostructure was designed in this work, and its electronic structure was investigated to explore its potential for water splitting. The assessments of binding energy, phonon spectrum, ab initio molecular dynamics, and elastic constants provide strong evidence for its stability. The ZnO/Sc2CF2 heterostructure has an indirect band gap of 1.93 eV with a type-Ⅰ band alignment. The electronic structure can be modified with strain, leading to a transition in band alignment from type-Ⅰ to type-Ⅱ. The heterostructure is suitable for water splitting since its VBM and CBM stride over the redox potential. The energy barrier and built-in electric field, resulting from the charge transfer, facilitate the spatial separation of photogenerated carriers, enhancing their utilization efficiency for redox processes. The photogenerated carriers in the heterostructures with lattice compression greater than 6% follow the direct-Z transfer mechanism. The ZnO/Sc2CF2 heterostructure is confirmed with high photocatalytic activity by a Gibbs free energy change of HER, which is 0.89 eV and decreases to −0.52 eV under an 8% compressive strain. The heterostructure exhibits a remarkable enhancement in both absorption range and intensity, which can be further improved with strains. All these findings suggest that the ZnO/Sc2CF2 heterostructure is an appreciated catalyst for efficient photocatalytic water splitting.
A Novel Approach to Waste Recycling and Dye Removal: Lithium-Functionalized Nanoparticle Zeolites
Authors: Guaya Diana , Debut Alexis , Campoverde Jhuliana
Published: September 2024

A zeolitic sample, named MT-ZLSH, was synthesized using mining tailings (MT) as the precursor material, resulting in a structure comprising: Linde type A (LTA) and sodalite-hydroxysodalite (ZLSH). This naming convention reflects the material’s origin and its structural characteristics. The material was further modified by incorporating lithium, producing MT-ZLSH-Li+. Physicochemical characterizations were performed, and the material was evaluated for its potential to remove methylene blue (MB) from synthetic wastewater through adsorption and photocatalysis. Efficient adsorption was observed under typical wastewater pH conditions, with a maximum adsorption capacity of 23.4 mg·g−1, which fit well with the Langmuir isotherm model. The key mechanisms governing MB adsorption were identified as ion exchange, electrostatic attraction, and hydrogen bonding. The adsorption process was exothermic, with kinetic data fitting both the pseudo-second order and intraparticle diffusion models, achieving 82% removal and a maximum adsorption capacity of 40 mg·g−1 over 12 h. MB adsorption followed a two-step process, initially involving film diffusion, followed by intraparticle diffusion. Additionally, photocatalytic degradation of MB achieved 77% degradation within 180 min. However, a decrease in reusability was observed during a second cycle of MB adsorption and photodegradation, highlighting the need for further optimization to enhance the material’s long-term performance.