Search Results (38)

With the increasingly severe problem of water shortage and the increasing contradiction between supply and demand, the optimal allocation of water resources has become an essential method for alleviating the water crisis. In this context, natural-element-inspired optimization algorithms have been extensively used to solve water resource optimization problems. The hunting search (HUS) algorithm has a slow convergence speed, and low accuracy, which makes it easy to fall into local optima when solving multi-objective problems, and it is also not easy to apply directly to multi-objective optimization. It is improved by introducing a fast, non-dominated sorting, congestion comparison operator, and elite retention strategy. The improved algorithm was evaluated against popular algorithms using the ZTD series of objective functions, and the results indicate that the improved algorithm performs better in terms of convergence and diversity of solution sets. The improved algorithm is then applied to solve the optimal allocation model for water resources in the receiving area of the South-to-North Water Diversion Project in Hebei Province, which is based on the objective of social and economic benefits. Based on the obtained Pareto optimal frontier, the scheme with a special preference for the minimum shortage of water resources is selected as the ultimate decision-making scheme. The optimization results show that in 2030, the total water demand of water users in the receiving area is 4661.82 × 10⁶ m³, the total water allocation is 4082.88 × 10⁶ m³, and the water deficit is 578.94 × 10⁶ m³. The improved hunting search algorithm offers a new solution method for the multi-objective water resource optimization allocation problem. Full article

Alfalfa (Medicago sativa) is a perennial forage crop with significant economic and ecological significance. If alfalfa can be planted in saline-alkali land, it will not only improve the utilization rate of marginal land and alleviate the competition between forage and cereal crops for arable land but will also increase the yield of high-quality domestic forage. In this study, we conducted transcriptomic analysis on the saline-alkali-tolerant alfalfa cultivar NQ-1 and compared its metabolite accumulation levels with saline-alkali-sensitive cultivars. The results showed that under saline-alkali stress, the photosynthesis and some secondary metabolic pathways in NQ-1 were activated, such as α-Linolenic acid metabolism, Phenylpropanoid and Flavonoid biosynthesis, and Photosynthesis-related pathways, providing substances and energy for enhancing NQ-1 stress tolerance. Furthermore, some specific flavonoids were detected that may contribute to the saline-alkali tolerance of NQ-1. In addition, transcription factors that may regulate flavonoid biosynthesis in NQ-1 under saline-alkali stress were also identified. This study deepens the understanding of the resistance mechanism of saline-alkali-tolerant cultivars of alfalfa and provides valuable information for molecular design breeding strategies for stress-resistant alfalfa. Full article

Consumers are increasingly demanding higher-quality mutton. Crossbreeding has been recognized as an effective means to improve meat quality. However, the phenomenon underlying these molecular system mechanisms remains largely unidentified. In this study, 48 male lambs aged 3 months were selected, including ♂ Hu sheep × ♀ Hu (HH, n = 16), ♂ Polled Dorset × ♀ Hu sheep F₁ hybrid lambs (DH, n = 16), and ♂ Southdown × ♀ Hu sheep (SH, n = 16) F₁ hybrid lambs, and raised in a single pen under the same nutritional and management conditions for 95 days. Then, seven sheep close to the average weight of the group were selected and fasted for 12 h prior to slaughter. By comparing the muscle fiber characteristics of the Longissimus dorsi of the three groups of sheep, and through transcriptomic and metabolomic analyses, we revealed molecular differences in the meat quality of Hu sheep crossbred with different parent breeds. The results of this study showed that muscle fiber diameter and cross-sectional area were significantly greater in the DH group than in the HH group, and collagen fiber content in the DH group was also significantly higher than in the HH group (p < 0.05). A total of 163 differential genes and 823 differential metabolites were identified in the three groups, most of which were related to muscle development and lipid metabolism. These included the AMPK signaling pathway, the PI3K-Akt signaling pathway, glycerophospholipid metabolism, and the related genes EFHB, PER3, and PPARGC1A. The results of this study offer valuable insights into the molecular mechanisms underlying the impact of crossbreeding on meat quality and provide a theoretical foundation for sheep crossbreed production. Full article

The degradation of black soil cropland has occurred to varying degrees in the northern agropastoral ecotone. Crop–forage rotation is an effective way to improve soil quality, with Medicago being the preferred perennial legume. The C, N, and P stoichiometric ratios are key indicators of soil quality and organic matter composition, reflecting the status of the internal C, N, and P cycles in soil. This study aims to investigate the ecological stoichiometric ratios of Medicago grassland soils with different planting durations, explore the regulatory effects of nitrogen fertilizer on soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) content, and assess the impacts of these changes on the Medicago grassland ecosystem. This study was conducted on the long-term cultivated grassland core experimental platform of the Hulunber National Field Station. Based on forage yield and soil nutrient measurements, field-based observations and laboratory analyses were carried out. Medicago × varia was the study subject, with different nitrogen fertilizer treatments: CK (0 kg N ha⁻¹), N₇₅ (75 kg N ha⁻¹), and N₁₅₀ (150 kg N ha⁻¹). A randomized block design was adopted. Variance analysis, boxplot statistics, and scatterplot fitting methods were used to examine soil properties and assess the effects of nitrogen application on the C, N, and P stoichiometry of soils in established perennial Medicago grasslands. The results indicate that, based on the growth characteristics of alfalfa, soil nutrient dynamics, and its effectiveness in improving soil quality, the optimal rotation period for alfalfa in the northern agropastoral ecotone is 4–5 years, but it can also be shortened to 3 years. Soil carbon, nitrogen, and phosphorus contents are significantly influenced by the planting duration. As the planting years increase, soil carbon and nitrogen contents first increase and then decrease, while soil phosphorus content initially decreases followed by a slight increase. Soil pH gradually rises with both planting years and soil depth. Both low and high levels of nitrogen fertilizer application reduce soil organic carbon concentration (by 0.40% and 10.14%, respectively). Low nitrogen fertilizer application increases soil nitrogen concentration (by 1.50%), whereas high nitrogen fertilizer application decreases it (by 7.6%). Both nitrogen levels increase soil phosphorus concentration (by 36.67% and 35.26%, respectively). For soil from an alfalfa grassland planted for 8 years, the carbon-to-nitrogen ratio ranges from 9.08 to 9.76, the carbon-to-phosphorus ratio from 13.00 to 151.32, and the nitrogen-to-phosphorus ratio from 1.65 to 17.14. In summary, alfalfa yield is primarily influenced by the nitrogen fertilizer application rate, planting duration, stoichiometric ratios, and pH. Nitrogen fertilizer application has a positive regulatory effect on soil stoichiometric ratios. The annual yield can reach 8.94 to 10.07 tons per hectare., but phosphorus remains a limiting factor. These findings provide crucial data for understanding the impact of ecological stoichiometry on crop–forage rotation cycles, as well as optimal land use and quality improvement. Full article

Rolling Bearings are important supporting components of rotating machines in industrial processes; the faults of rolling bearings will cause the deterioration of the operation conditions of rotating machines. How to effectively extract the fault features and identify the fault modes of rolling bearings quickly and accurately has become a key issue for the safe operation of rotating machines. In this paper, a novel hybrid fault diagnosis method of an optimized random forests classifier for rolling bearings is proposed. Firstly, the original vibration signals are decomposed by recursive variational mode decomposition (RVMD), and the typical time–frequency domain features are extracted from decomposed signals at different scales. The Relief-F ranking method is utilized to assess the quality of time–frequency domain features, and the top-ranked features with high weight gain are selected for identifying the fault modes. Then, an improved bee colony algorithm is proposed based on the simulated binary crossover criterion, which is used to optimize the key parameters of random forests (RF). Finally, several experiments are conducted on the Case Western Reserve University bearing dataset and the dataset collected from our rolling bearing fault testbed. The experimental results show that the proposed method can accurately identify bearing faults and outperform other state-of-the-art methods. Full article

Background: Several COVID-19 vaccines were developed and approved in China. Of these, the BIBB-CorV and CoronaVac inactivated whole-virion vaccines were widely distributed in China and developing countries. However, the performance of the two vaccines in the real world has not been summarized. Methods: A living systematic review based on findings from ongoing post-licensure studies was conducted, applying standardized algorithms. Articles published between 1 May 2020 and 31 May 2022 in English and Chinese were searched for in Medline, Embase, WanFang Data, medRxiv, bioRxiv, arXiv, SSRN, and Research Square, using SARS-CoV-2, COVID-19, and vaccine as the MeSH terms. Studies with estimates of safety, immunogenicity, and effectiveness from receiving the BIBB-CorV or CoronaVac vaccine that met the predefined screening criteria underwent a full-text review. The Joanna Briggs Institute’s Critical Appraisal Checklist and the Cochrane risk of bias were used for assessment of the quality. A random-effects meta-regression model was applied to identify the potential impact factors on the vaccines’ effectiveness. Results: In total, 32578 articles were identified, of these, 770 studies underwent a full-text review. Eventually, 213 studies were included. The pooled occurrence of solicited and unsolicited adverse events after any dose of either vaccine varied between 10% and 40%. The top five commonly reported rare adverse events were immunization stress-related responses (211 cases, 50.0%), cutaneous responses (43 cases, 10.2%), acute neurological syndrome (39 cases, 9.2%), anaphylaxis (17 cases, 4.0%), and acute stroke (16 cases, 3.8%). The majority (83.3%) recovered or were relieved within several days. The peak neutralization titers against the ancestral strain was found within 1 month after the completion of the primary series of either vaccine, with a GMT (geometric mean titer) of 43.7 (95% CI: 23.2–82.4), followed by a dramatic decrease within 3 months. At Month 12, the GMT was 4.1 (95% CI: 3.8–4.4). Homologous boosting could restore humoral immunity, while heterologous boosting elicited around sixfold higher neutralization titers in comparison with homologous boosting. The effectiveness of receiving either vaccine against death and severe disease was around 85% for both shortly after the primary series. At Month 12, the protection against death did not decline, while the protection against severe disease decreased to ~75%. Conclusions: Both the BIBP-CorV and CoronaVac inactivated vaccines are safe. Sustained vaccine effectiveness against death was determined 12 months after the primary series, although protection against severe disease decreased slightly over time. A booster dose could strengthen the waning effectiveness; however, the duration of the incremental effectiveness and the additional benefit provided by a heterologous booster need to be studied. Full article

In this study, processing tomato (Solanum lycopersicum L.) ‘Ligeer 87-5’ was hydroponically cultivated under 100 mM NaCl to simulate salt stress. To investigate the impacts on ion homeostasis, osmotic regulation, and redox status in tomato seedlings, different endogenous levels of ascorbic acid (AsA) were established through the foliar application of 0.5 mM AsA (NA treatment), 0.25 mM lycorine (LYC, an inhibitor of AsA synthesis; NL treatment), and a combination of LYC and AsA (NLA treatment). The results demonstrated that exogenous AsA significantly increased the activities and gene expressions of key enzymes (L-galactono-1,4-lactone dehydrogenase (GalLDH) and L-galactose dehydrogenase (GalDH)) involved in AsA synthesis in tomato seedling leaves under NaCl stress and NL treatment, thereby increasing cellular AsA content to maintain its redox status in a reduced state. Additionally, exogenous AsA regulated multiple ion transporters via the SOS pathway and increased the selective absorption of K⁺, Ca²⁺, and Mg²⁺ in the aerial parts, reconstructing ion homeostasis in cells, thereby alleviating ion imbalance caused by salt stress. Exogenous AsA also increased proline dehydrogenase (ProDH) activity and gene expression, while inhibiting the activity and transcription levels of Δ1-pyrroline-5-carboxylate synthetase (P5CS) and ornithine-δ-aminotransferase (OAT), thereby reducing excessive proline content in the leaves and alleviating osmotic stress. LYC exacerbated ion imbalance and osmotic stress caused by salt stress, which could be significantly reversed by AsA application. Therefore, exogenous AsA application increased endogenous AsA levels, reestablished ion homeostasis, maintained osmotic balance, effectively alleviated the inhibitory effect of salt stress on tomato seedling growth, and enhanced their salt tolerance. Full article

A layered Ti₃C₂T_x MXene structure was prepared by etching MAX-phase Ti₃AlC₂ with hydro-fluoric acid (HF), followed by alkalization in sodium hydroxide (NaOH) solutions of varying concentrations and for varying durations. Compared to sensors utilizing unalkalized Ti₃C₂T_x, those employing alkalized Ti₃C₂T_x MXene exhibited enhanced sensitivity for NH₃ detection at room temperature and a relative humidity of 40%. Both the concentration of NaOH and duration of alkalization significantly influenced sensor performance. Among the tested conditions, Ti₃C₂T_x MXene alkalized with a 5 M NaOH solution for 12 h exhibited optimal performance, with high response values of 100.3% and a rapid response/recovery time of 73 s and 38 s, respectively. The improved sensitivity of NH₃ detection can be attributed to the heightened NH₃ adsorption capability of oxygen-rich terminals obtained through the alkalization treatment. This is consistent with the observed increase in the ratio of oxygen to fluorine atoms on the surface terminations of the alkalization-treated Ti₃C₂T_x. These findings suggest that the gas-sensing characteristics of Ti₃C₂T_x MXene can be finely tuned and optimized through a carefully tailored alkalization process, offering a viable approach to realizing high-performance Ti₃C₂T_x MXene gas sensors, particularly for NH₃ sensing applications. Full article

This paper aims to perform a comparative investigation on the corrosion protection of steel in the simulated pore solutions of alkali-activated slag (SH) by NO₃⁻ and NO₂⁻ intercalated Mg-Al layered double hydroxides (MAL) which were fabricated by the calcination rehydration method. The corrosion potential, electrochemical impedance spectroscopy, potentiodynamic polarization and corrosion condition of steel were measured. Furthermore, changes in the microstructures of NO₃⁻ intercalated MAL (MAL-N3) and NO₂⁻ intercalated MAL (MAL-N2) before and after the adsorption of chloride ion were observed by X-ray diffraction and Fourier transform infrared spectroscopy. The results show that compared to the simulated concrete pore solution (OPCH), MAL-N3 and MAL-N2 exhibit lower chloride adsorption capacities and better corrosion inhibition effects in SH. The chloride adsorption capacity of MAL-N2 is lower compared with that of MAL-N3 due to the different volumes of intercalated anions. In contrast, MAL-N2 presents superior corrosion inhibition than MAL-N3. Furthermore, the decreases in [OH⁻] in SH due to the additions of MAL-N3 and MAL-N2 are more prominent than those in OPCH. The different synergistic effects due to the competitive anion-exchanges in the interlayers of NO₃⁻ and NO₂⁻ intercalated MAL in the two solutions contribute to the above effects. Full article

Morphological engineering and semiconductor coupling show significant potential to increase the photocatalytic performance of graphite carbon nitride (g-C₃N₄). In this work, a unique Z-scheme heterojunction photocatalyst composed of tubular g-C₃N₄ (TCN) and α-F₂O₃ was successfully synthesized. Combining the experimental results and characterization, we extensively investigated the charge transfer mechanism of the α-F₂O₃/tubular g-C₃N₄ (FO-TCN) heterojunctions and processes in the photocatalytic degradation of tetracycline (TC). The tubular morphology provided a larger specific surface area, enhancing the light absorption area and thus improving the exposure of the active sites. Not only was the light absorption range expanded through the coupling with α-F₂O₃, but the charge transfer properties of the sample were also strengthened. The synergism between photocatalysis and the Fenton reaction enhanced the photocatalytic performance of the FO-TCN. Due to the previously mentioned beneficial factors, the performance of the FO-TCN photocatalyst was significantly increased; its reaction rate k value in the degradation of TC (0.0482 min⁻¹) was 4.05 times faster than that of single g-C₃N₄ and it exhibited the best photocatalytic performance (95.02%) for the degradation of TC in 60 min, with an enhancement of 38.41%. Quenching experiments showed that h⁺ and ·O₂⁻ were the major active substances in the photocatalytic degradation process. Full article

Milk is one of the preferred beverages in modern healthy diets, and its freshness is of great significance for product sales and applications. By combining the two-dimensional (2D) correlation spectroscopy technique and chemometrics, a new method based on visible/near-infrared (Vis/NIR) spectroscopy was proposed to discriminate the freshness of milk. To clarify the relationship be-tween the freshness of milk and the spectra, the changes in the physicochemical indicators of milk during storage were analyzed as well as the Vis/NIR spectra and the 2D-Vis/NIR correlation spectra. The threshold-value method, linear discriminant analysis (LDA) method, and support vector machine (SVM) method were used to construct the discriminant models of milk freshness, and the parameters of the SVM-based models were optimized by the grid search method and particle swarm optimization algorithm. The results showed that with the prolongation of storage time, the absorbance of the Vis/NIR spectra of milk gradually increased, and the intensity of autocorrelation peaks and cross peaks in synchronous 2D-Vis/NIR spectra also increased significantly. Compared with the SVM-based models using Vis/NIR spectra, the SVM-based model using 2D-Vis/NIR spectra had a >15% higher prediction accuracy. Under the same conditions, the prediction performances of the SVM-based models were better than those of the threshold-value-based or LDA-based models. In addition, the accuracy rate of the SVM-based model using the synchronous 2D-Vis/NIR autocorrelation spectra was >97%. This work indicates that the 2D-Vis/NIR correlation spectra coupled with chemometrics is a great pattern to rapidly discriminate the freshness of milk, which provides technical support for improving the evaluation system of milk quality and maintaining the safety of milk product quality. Full article

To clarify the effects of dietary inflammatory and pro-oxidative potential, we investigated the impact of the Dietary Inflammation Index (DII) and the Dietary Oxidative Balance Score (DOBS) on all-cause and disease-specific mortality. For DII and DOBS, 17,550 and 24,527 participants were included. Twenty-six and seventeen dietary factors were selected for scoring. Cox proportional hazards regression models were used. DII and DOBS were significantly associated with all-cause, CVD, and cancer mortality in this nationally representative sample of American adults. Compared with the lowest DII, the multivariable-adjusted hazard ratios (95% CI) of all-cause, CVD, and cancer mortality for the highest were 1.49 (1.23–1.80), 1.58 (1.08–2.33), and 1.56 (1.07–2.25). The highest quartile of DOBS was associated with the risk of all-cause death (HR 0.71, 95% CI 0.59–0.86). Pro-inflammatory and pro-oxidative diets were associated with increased risk for all-cause (HR 1.59, 95% CI 1.28–1.97), and CVD (HR 2.29, 95% CI 1.33–3.94) death compared to anti-inflammatory and antioxidant diets. Similar results were observed among the stratification analyses. Inflammation-reducing and oxidative-balancing diets are linked to lower all-cause and CVD mortality. Diets impact health by regulating inflammation and oxidative stress. Full article

Panax notoginseng (P. notoginseng) has excellent medicinal and food dual-use characteristics. However, P. notoginseng with a unique origin label has become the target of fraud because of people confusing or hiding its origin. In this study, an untargeted nuclear magnetic resonance (NMR)-based metabolomics approach was used to discriminate the geographical origins of P. notoginseng from four major producing areas in China. Fifty-two components, including various saccharides, amino acids, saponins, organic acids, and alcohols, were identified and quantified through the NMR spectrum, and the area-specific geographical identification components were further screened. P. notoginseng from Yunnan had strong hypoglycemic and cardiovascular protective effects due to its high acetic acid, dopamine, and serine content, while P. notoginseng from Sichuan was more beneficial for diseases of the nervous system because of its high content of fumarate. P. notoginseng from Guizhou and Tibet had high contents of malic acid, notoginsenoside R1, and amino acids. Our results can help to distinguish the geographical origin of P. notoginseng and are readily available for nutritional recommendations in human consumption. Full article

The electrochemical reduction of CO₂ is an efficient method to convert CO₂ waste into hydrocarbon fuels, among which methanol is the direct liquid fuel in the direct methanol fuel cells (DMFC). Copper is the most widely used catalyst for CO₂ reduction reaction (CO₂RR); the reaction is affected by the surface morphology of the copper. Here, the morphology effect and the mechanism of CO₂RR on three typical low-index Cu (100), Cu (110) and Cu (111) surfaces are studied. According to our results, Cu (110) provides the optimum surface for the CO₂RR via CO₂ → *COOH → *CO → *CHO → *CH₂O → *CH₂OH → CH₃OH pathway, where the reduction reaction of CO₂ to *COOH is the potential-determining step (PDS). This is because Cu (110) has the highest d band center, which promotes the adsorption of *COOH. Full article

This study investigated the protective effects of exogenous ascorbic acid (AsA, 0.5 mmol·L⁻¹) treatment on salt-induced photosystem inhibition in tomato seedlings under salt stress (NaCl, 100 mmol·L⁻¹) conditions with and without the AsA inhibitor lycorine. Salt stress reduced the activities of photosystem II (PSII) and PSI. AsA treatment mitigated inhibition of the maximal photochemical efficiency of PSII (F_v/F_m), maximal P700 changes (P_m), the effective quantum yields of PSII and I [Y(II) and Y(I)], and non-photochemical quenching coefficient (NPQ) values under salt stress conditions both with and without lycorine. Moreover, AsA restored the balance of excitation energy between two photosystems (β/α-1) after disruption by salt stress, with or without lycorine. Treatment of the leaves of salt-stressed plants with AsA with or without lycorine increased the proportion of electron flux for photosynthetic carbon reduction [Je(PCR)] while decreasing the O₂-dependent alternative electron flux [Ja(O₂-dependent)]. AsA with or without lycorine further resulted in increases in the quantum yield of cyclic electron flow (CEF) around PSI [Y(CEF)] while increasing the expression of antioxidant and AsA–GSH cycle-related genes and elevating the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG). Similarly, AsA treatment significantly decreased the levels of reactive oxygen species [superoxide anion (O₂⁻) and hydrogen peroxide (H₂O₂)] in these plants. Together, these data indicate that AsA can alleviate salt-stress-induced inhibition of PSII and PSI in tomato seedlings by restoring the excitation energy balance between the photosystems, regulating the dissipation of excess light energy by CEF and NPQ, increasing photosynthetic electron flux, and enhancing the scavenging of reactive oxygen species, thereby enabling plants to better tolerate salt stress. Full article