Search Results (98)

The aim of this study was to determine the connection between oscillations in operating pressure values and the appearance of various irregularities on machined surfaces. Such oscillations are a consequence of the high water pressure generated during abrasive water jet machining. Oscillations in the operating pressure values are periodic, namely due to the cyclic operation of the intensifier and the physical characteristics of water. One of the most common means of reducing this phenomenon is installing an attenuator in the hydraulic system or a phased intensifier system. The main hypothesis of this study was that the topography of a machined surface is directly influenced by the inability of the pressure accumulator to fully absorb water pressure oscillations. In this study, we monitored changes in hydraulic oil pressure values at the intensifier entrance and their connection with irregularities on the machined surface—such as waviness—when cutting aluminum AlMg3 of different thicknesses. Experimental research was conducted in order to establish this connection. Aluminum AlMg3 of different thicknesses—from 6 mm to 12 mm—was cut with different traverse speeds while hydraulic oil pressure values were monitored. The pressure signals thus obtained were analyzed by applying the fast Fourier transform (FFT) algorithm. We identified a single-sided pressure signal amplitude spectrum. The frequency axis can be transformed by multiplying inverse frequency data with traverse speed; in this way, a single-sided amplitude spectrum can be obtained, examined against the period in which striations are expected to appear (in millimeters). In the lower zone of the analyzed samples, striations are observed at intervals determined by the dominant hydraulic oil pressure harmonics, which are transferred to the operating pressure. In other words, we demonstrate how the machined surface topography is directly induced by water jet pressure frequency characteristics. Full article

The root conformation of soybean is critical to achieve physiological activities such as nodulation and nitrogen fixation; however, the molecular determinants behind genotypic differences in its early development remain poorly described. In this study, we compared the characteristics of the soybean varieties HN75 and HN76 and examined developmental disparities in their root architectural characteristics and the transcriptomic profiles of radicles between them. The plant height and 100-grain weight of HN75, which had a longer growth cycle of 170 days, were slightly higher than those of HN76, which had a shorter growth cycle of 120 days. However, the numbers of pods and grains per plant were slightly lower. In terms of quality traits, HN75 had a higher oil content (23.40% versus 21.50%), whereas HN76 had a higher protein content (41.39% versus 35.71%). HN75 exhibited markedly superior root elongation (13.27 cm versus 10.15 cm), enhanced lateral root proliferation, and significantly greater nodule formation (19.53 versus 8.60 nodules per plant) relative to HN76 at 30 days post-germination, notwithstanding comparable nodule biomass. Chronobiological analysis (0–96 h post-germination) identified a pivotal developmental window of 48–72 h post-germination. Transcriptomic profiling of radicle tissues revealed 4792 differentially expressed genes (DEGs) in HN75 compared to 896 in HN76 during this critical interval, indicating substantially heightened transcriptional activity in HN75. Functional annotation enrichment demonstrated that HN75 DEGs were significantly enriched in phytohormone signalling cascades and isoprenoid biosynthetic pathways, whereas HN76 DEGs were predominantly associated with protein processing within the endoplasmic reticulum. We screened for eight genes (Glyma 10G071400, Glyma 13G057500, Glyma 08G016900, Glyma 09G028000, Glyma 18G265800, Glyma 03G032800, Glyma 02G064100, and Glyma 01G238600) that may play a role in the critical period of radicle development by performing network analyses and verified their dramatic changes in expression during this period by qRT-PCR. These results elucidate varietal-specific physiological and molecular mechanisms governing early radicle development in soybeans. These findings unravel mechanisms governing leguminous radicle development while establishing molecular blueprints for engineering cultivation protocols that would enhance soybean sustainability in edaphically constrained environments. Full article

This study develops an integrated methodological approach for interpreting used oil analysis results in diesel engines, focusing on optimizing maintenance strategies. The methodology combines a literature review with a quantitative assessment of 156 lubricant analysis reports from a fleet of diesel waste collection trucks operating in Cuenca, Ecuador, a high-altitude city. The framework includes critical limits for key lubricant parameters, correlation analysis, and Principal Component Analysis (PCA) to identify dominant degradation mechanisms. The Binary Segmentation (BS) algorithm is also used for Change-Point Detection. The findings indicate four primary degradation pathways: thermal–chemical degradation influenced by sulfur, oxidation, and soot; metallic wear and base depletion, involving iron, chromium, and copper; external contamination linked to silica and copper; and viscosity alteration due to lubricant aging. Significant degradation shifts were identified at approximately 346 and 444 service hours, suggesting critical points for condition-based maintenance interventions. This study highlights the effectiveness of multivariate statistical tools in enhancing the interpretation of used oil analysis and optimizing predictive maintenance strategies. The integration of Change-Point Detection and multivariate analysis provides a robust framework for defining oil change intervals based on lubricant condition rather than fixed time- or mileage-based criteria. This approach offers practical benefits for fleet operations, enabling the reduction in operational costs, enhancing engine reliability, and minimizing the environmental impact of unnecessary lubricant changes. Full article

This study aimed to establish a hyperlipidemia model in ICR mice using a homemade high-fat diet. It further investigated hyperlipidemia-related indicators in control and model mice at various feeding durations to determine the optimal time frame for successful model establishment. Sixteen male ICR mice were introduced at intervals of 3 weeks, starting from weeks 0, 3, 6, 9, and 12. The control group was fed a standard diet, while the model group received a homemade high-fat diet to induce hyperlipidemia. Blood lipid related indices were detected at 15 weeks. The liver, scapular fat, abdominal fat, and epididymal fat were harvested to calculate the organ index. The contents of T-CHO, TG, and TBA in the liver were measured. HE staining was used to observe pathological changes in liver tissue and white adipose tissue, while Oil Red O staining was used to observe lipid droplets in liver tissue. The mRNA and protein expression of SREBP-2, insig1, HMGCR, LXRα, ABCA1, and CYP7A1 in the liver were detected by RT-qPCR and Western Blot. In the model group, blood lipid levels significantly increased by the 9th week, aligning with pathological changes indicative of hyperlipidemia. The mRNA and protein expression levels of SREBP-2, Insig-1, HMGCR, LXRα, ABCA1, and CYP7A1 were markedly elevated at 9 weeks and remained relatively stable thereafter. This study provides a reliable reference for determining the optimal establishment time of hyperlipidemia models and for in vivo hyperlipidemia animal experiments. Full article

Soybean oil is susceptible to thermal deterioration, especially during the deep-frying process due to its high polyunsaturated fatty acids. Soybean oil has been employed to enhance the nutritional profile and thermal stability by simply blending it with other oils, including palm olein, camelia, sesame, and cashew nut oil. In particular, coconut oil is more resistant to oxidation than those oils, so adding it to soybean oil that is prone to oxidation can make the mixture more stable. Therefore, this study aims to investigate the thermal stability of soybean oil by blending it with coconut oil and evaluating the blend’s physicochemical changes during the continuous deep frying of banana chips. Refined soybean oil was blended with refined coconut oil at different ratios (% v/v), including 100:0 (A), 80:20 (B), 70:30 (C), and 60:40 (D). All the mixtures were used for continuous deep frying at a constant temperature of 180 °C. The banana chips were fried for 1 min at 5 min intervals over a total of nine batches. The findings show that changes in the physicochemical properties of the frying oils were significantly affected by the soybean oil to coconut oil ratios and the frying duration, which were analyzed using a two-way analysis of variance (p < 0.05). The alteration in free fatty acids and peroxide values were found to be the lowest in treatment C, followed by D < B < A, by using a two-way analysis of variance (p < 0.05). Conversely, the highest total oxidation value was found in treatment A, followed by B > C > D. The lightness of the oil reached the highest value in the last frying cycle in treatments B and C, followed by D and A, while the color of the fried banana chips achieved the maximum value in treatment D, followed by C < B < A. In addition, the lipid content in the fried banana chips was observed to be the lowest in treatments D and C compared to B and A. This study indicated that blending highly unsaturated soybean oil with coconut oil could enhance its thermal stability. Consequentially, a 70:30 (% v/v) ratio of soybean oil with coconut oil exhibited good thermal stability during continuous deep frying. This study provides insights into an alternative blending technique for soybean and coconut oils to improve the thermal stability of frying oil during continuous deep frying. Full article

Organic matter (OM) is the primary carrier for the generation and occurrence of shale oil and gas. The combination of sequence stratigraphy and elemental geochemistry plays a crucial role in the study of organic matter enrichment mechanisms in marine shale, but it is rarely applied to terrestrial lacustrine basins. As a product of the last large-scale lake transgression in the Sichuan Basin, the Early Jurassic Lianggaoshan Formation (LGS Fm.) developed multiple organic-rich shale intervals, which is a good example for studying the OM enrichment in lacustrine basins. Based on a high-resolution sequence stratigraphic framework, the evolutionary process of terrestrial debris input, redox conditions, and paleo-productivity during the sedimentary period of the Lianggaoshan Formation lacustrine shale at different stages of lake-level variations has been revealed. The main controlling factors for OM enrichment and the establishment of their enrichment patterns have been determined. Sequence stratigraphy studies have shown that there are three third-order lake transgression-lake regression (T-R) cycles in the LGS Formation. The total organic carbon content (TOC) is higher in the TST cycle, especially in the T-R3 cycle, and lower in the RST cycle. There are differences in the redox conditions, paleo-productivity, terrestrial detrital transport, and OM accumulation under the influence of lacustrine shale deposition in different system tracts. The results indicate that changes in lake level have a significant impact on the reducibility of bottom water and paleo-productivity of surface seawater, but have a relatively small impact on the input of terrestrial debris. In the TST cycle, the reducibility of bottom water gradually increases, and the paleo-productivity gradually increases, while in the RST cycle, the opposite is true. Within the TST cycle, the OM accumulation is mainly influenced by paleo-productivity and redox condition of bottom water, with moderate input of terrestrial debris playing a positive role. In the RST cycle, the redox condition of bottom water is the main inducing factor for OM enrichment, followed by paleo-productivity, while terrestrial input flux plays a diluting role, which is generally not conducive to OM accumulation. Full article

Delayed or failed postpartum estrus can impede the reproductive performance of rebreeding dams. Our study aimed to test whether dietary fish oil can promote estrus return and improve fecal microbiota in multiparous sows. Forty-five sows were randomly allocated into three treatments: a basal diet, or a basal diet plus 30 or 60 g/day of fish oil from gestation day 90 to lactation day 21. Results showed that dietary fish oil significantly elevated circulating DHA in sows, without significant changes in litter size, litter weight, or backfat loss. Supplementation of fish oil (30 or 60 g/day) shortened the interval from weaning to estrus by 1.8 days and 1.67 days, respectively, associated with a significant boost of estradiol. Increases in prolactin and IgA were only significant in the high-dosage group. In addition, plasma MDA and antioxidant activities were up-regulated by fish oil, combined with elevated serum IL-1β and IL-6. Moreover, dietary fish oil significantly reduced serum zonulin, improved the Simpson index of fecal microbiota, and increased the abundance of Lactobacillus and Ruminococcaceae_UCG-014 genera. In conclusion, dietary omega-3 PUFA-enriched fish oil provides a promising approach to aiding estrus return and reshaping fecal microbiota in post-weaning sows. Full article

Nuclear magnetic resonance (NMR) and high-pressure mercury injection (HPMI) have been widely used as common characterization methods of pore-throat. It is generally believed that there is a power function relationship between transverse relaxation time (T₂) and pore-throat radius (r), but the segmentation process of the pore-throat interval is subjective, which affects the conversion accuracy. In this paper, ordered clustering is used to improve the existing segmentation method of the pore-throat interval, eliminate the subjectivity in the segmentation process, and obtain a more accurate distribution curve of the pore-throat. For the three kinds of cores with ordinary-low permeability (K > 1 mD), ultra-low permeability (0.1 mD < K < 1 mD), and super-low permeability (K < 0.1 mD), the pore-throat distribution curves of the cores were obtained by using the improved T₂ conversion method. Then, the oil and gas two-phase displacement experiment was carried out to investigate the degree of recovery and cumulative gas–oil ratio changes during the displacement process. Finally, the converted T₂ spectrum was used to quantify the utilization of different pore sizes. The improved T₂ conversion method not only has better accuracy but also is not limited by the pore-throat distribution types (such as unimodal, bimodal, and multi-modal, etc.) and is suitable for any core with measured HPMI pore-throat distribution and an NMR T₂ spectrum. Combined with the results of core displacement and the degree of pore-throat utilization, it is found that the potential of miscible flooding to improve the recovery degree is in the order of ordinary-low permeability core (18–22%), ultra-low permeability core (25–29%), and super-low permeability core (8–12%). The utilization degree of immiscible flooding to the <10 nm pore-throat is low (up to 35%), while miscible flooding can effectively use the <3.7 nm pore-throat (up to 73%). The development effect of supercritical CO₂ flooding on K < 0.1 mD reservoirs is not good, the seepage resistance of CO₂ is large, the miscible flooding makes it difficult to improve the recovery degree, and the utilization effect of pore-throat is poor. Full article

This study investigates the operational properties of mineral lubricating oil in gas engines used in cogeneration systems, with a focus on factors contributing to the degradation of lubricating properties critical for energy efficiency and system management. The research was conducted on a 4.3 MW gas engine operating for about 90,000 machine hours, using natural gas as fuel. Data obtained from SCADA (Supervisory Control and Data Acquisition) systems and laboratory analysis were utilized to establish oil quality criteria, enabling the prediction of oil degradation and optimization of oil change intervals. Parameters including viscosity, contamination levels, Total Base Number (TBN), and Total Acid Number (TAN), were identified as significant indicators of oil performance and engine reliability. The findings revealed that oil change intervals could be extended by an average of 37% compared to standard schedules, thereby minimizing unnecessary maintenance downtimes, enhancing system availability, and increasing electrical and thermal energy output. Optimized oil utilization reduced material costs for oil and filter replacements, lowering expenditures from 3021 to 1887 EUR per machine hour. Additionally, the predicted Global Warming Potential (GWP) for prematurely consumed oil amounted to 68 × 10³ kg CO₂ eq., while avoidable waste generation reached 18.2 m³ of mineral oil. Regular oil analysis conducted every 1000 operating hours proved critical for early detection of oil degradation, supporting proactive maintenance strategies and ensuring optimal engine performance and longevity. Full article

Background: Dyslipidemia, a leading risk factor for cardiovascular diseases (CVDs), significantly contributes to global morbidity and mortality. Rice bran, rich in bioactive compounds such as γ-oryzanol and tocotrienols, has demonstrated promising lipid-modulating effects. Objective: This meta-analysis aimed to evaluate the effects of rice bran on lipid profiles, including triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), and identify factors influencing its efficacy across different populations and intervention conditions. Methods: A systematic search of PubMed, Web of Science, and Scopus was conducted to identify randomized controlled trials (RCTs) published up to November 2024. Effect sizes were calculated as mean differences with 95% confidence intervals (CIs). Subgroup analyses were performed based on intervention form, dosage, duration, region, and participant characteristics. Heterogeneity was estimated by the I² statistic, and sensitivity analyses were conducted to assess the robustness of the findings. Results: Eleven RCTs involving 572 participants met the inclusion criteria. Pooled results showed that rice bran consumption significantly reduced TG (−15.13 mg/dL; 95% CI: −29.56, −0.71), TC (−11.80 mg/dL; 95% CI: −19.35, −4.25), and LDL-C (−15.11 mg/dL; 95% CI: −24.56, −5.66) with moderate heterogeneity (I² = 38.1–63.0%). No significant changes were observed for HDL-C. Subgroup analyses showed that rice bran oil had greater effects on TC and LDL-C than whole rice bran. High-dose interventions (≥30 g/mL) and longer durations (>4 weeks) yielded stronger effects. Asian populations demonstrated greater reductions compared to Western populations. Conclusion: Rice bran, especially in the form of rice bran oil, significantly improves lipid profiles, supporting its role as a functional food for CVD prevention. Future research should focus on long-term studies with diverse populations to confirm its efficacy and explore underlying mechanisms. Full article

The Yanchang Formation of the Triassic in the Ordos Basin comprises various stratigraphic intervals. The Chang 8 reservoir represents a significant oil-producing section of the Yanchang Formation, and its hydrocarbon accumulation mechanism is complex. In this study, we analyzed the diagenetic evolution and reservoir-forming stages of the Chang 8 member of the Yanchang Formation in the Late Triassic in the Fuxian area, the southern Ordos Basin, via thin-section casting, scanning electron microscopy (SEM), X-ray diffraction, and fluid inclusion petrology and homogenization temperature analyses. The relationship between the petrogenesis and hydrocarbon charging history was analyzed, which provided guidance for identifying and predicting the hydrocarbon reservoir distribution. The results show that the main diagenesis types of the Chang 8 reservoir are compaction, cementation, dissolution, and metasomatism. The comprehensive analysis of the reservoir mineral types, diagenesis, diagenetic sequence, and thermal evolution degree of organic matter shows that the Chang 8 reservoir of the Yanchang Formation is in the A stage of the middle diagenesis stage. Under the overpressure of hydrocarbon generation, oil and gas migrated into the Chang 8 reservoir along fractures and connected pores. The earlier-stage hydrocarbon charging occurred after compaction and later than the early clay film formation and early calcite precipitation, and it also occurred earlier than or simultaneously with the quartz overgrowth. The later hydrocarbon charging occurred after the significant quartz overgrowth and late calcite pore filling. Depending on the homogenization temperature and salinity, the fluid inclusions can be divided into two types: low-temperature, low-salt (90–105 °C, 1.4%–11.2%) fluid inclusions and high-temperature, high-salt (115–120 °C, 2.2%–12.5%) fluid inclusions. According to the analysis of the evolution of the burial history, hydrocarbon charging in the Chang 8 reservoir of the Yanchang Formation in the Fuxian area occurred in two consecutive periods: 133~126 Ma and 122~119 Ma, demonstrating one-scene, two-stage reservoir formation, characterized by simultaneous reservoir densification and hydrocarbon charging. In this research, we precisely ascertained the regional diagenetic characteristics and patterns and periods of hydrocarbon charging, thereby furnishing crucial evidence that deepens the comprehension of sedimentary basin evolution. Full article

For oil and gas reservoir characterization, permeability prediction is indispensable because it helps identify potential flow pathways and lowers risk. Estimating permeability in heterogeneous media is challenging due to the limited number of measurement tools, low-resolution sampling methods, and sampling bias. To combat these issues, we employed a probe permeameter to produce a high-resolution (4 in [10 cm] spacing) permeability dataset for cores from the Strawn Formation, Katz Field, Permian Basin, Texas, USA. We structured our sampling to record permeability changes related to facies variability and fluctuating bioturbation intensity. We compared probe permeameter data to wireline logs and core-plug porosity and permeability data recorded at larger spacings. The results show that permeability is affected by facies type, bioturbation intensity, and cementation. The effects of bioturbation are non-linear; in our study, moderate bioturbation enhances permeability by improving connections between sands while intense bioturbation decreases permeability by redistributing fines. Core-plug and probe measurements gave similar permeability values, but the number of core plugs taken in the finer-grained intervals was insufficient. The probe, however, provided better resolution and gave larger net-to-gross sand ratios than core-plug-based evaluations. Using only the core-plug porosity–permeability relationship with wireline density log porosities led to permeability predictions too large by a factor of three or more compared to averaged probe permeameter values. Full article

Hempseed oil (HSO) is extremely rich in unsaturated fatty acids, especially linoleic (18:2 n-6) and α-linolenic (18:3 n-3) acids, which determine its high sensitivity to oxidative and photo-oxidative degradations that can lead to rancidity despite the presence of antioxidant compounds. The aim of this work was to evaluate which material/temperature/light solutions better preserve HSO quality during its shelf life and to test NIR as a rapid, non-destructive technique for monitoring oxidation phenomena. Futura 75 hemp seeds were cold-pressed; the oil was packed into 20 mL vials of four different materials (polypropylene, clear glass, amber glass, and amber glass coated with aluminum foil) and stored for 270 days at 25 °C under diffused light and at 10 °C in dark conditions., Peroxides and conjugated dienes and trienes were evaluated at intervals to monitor oil stability. Moreover, NIR spectra were measured in transmission, and the sample dataset was analyzed using ASCA to test the significance of the experimental factors: the model showed the significance of all factors and of all the simple interactions. Our results demonstrate that oil stored in amber glass vials with aluminum foils at refrigerated temperatures receive the highest protection from environmental conditions, mitigating oxidative changes, and that the NIR technique could be used to rapidly monitor HSO oxidation parameters. Full article

Sleep deprivation (SD) disrupts circadian rhythms; however, its effects on SD and the mechanisms involved require further investigation. Previous studies on SD were mainly conducted on rodents, such as mice, with few studies on its effects on the liver of large diurnal animals, such as sheep. In this study, we used a Tibetan sheep model for the first time to investigate the effects of SD on the liver by exposing Tibetan sheep (Ovis aries) to 7 days of SD (6 h/day) and performed transcriptome sequencing analysis on liver samples taken at 4 h intervals over 24 h. The results revealed that SD significantly altered the circadian expression of genes and their expression patterns in the liver of Tibetan sheep. Enrichment analysis of the circadian rhythm-altered genes revealed changes in the pathways related to lipid metabolism in the liver. Further evidence from serum markers and gene expression analyses using qualitative real-time polymerase chain reaction and Oil Red O and apoptosis staining indicated that SD leads to abnormal lipid metabolism in the liver, potentially causing liver damage. Therefore, our results suggest that SD disrupts the circadian rhythms of metabolism-related genes in the Tibetan sheep liver, thereby affecting metabolic homeostasis. Full article

A problem has been noted regarding the admixture of fuel to a low viscosity lubricant in hybrid electric vehicles (HEVs). This is very detrimental to the wear and tear of engine operating components. In this study, the operating conditions of HEVs were analysed. Using X-ray fluorescence spectrometry (XRF), engine oils of two different viscosity classes were compared after the operating process and these data were compared with fresh reference samples. Attention was paid to the content of elements such as Ca, Zn, Mo, Sn, Cd, Fe Pb, Si, Cu, and Ni. The depletion of anti-wear additives, as well as the higher content of metallic wear products relative to the operated 5W30 (engine oil), contributed to the overall assessment of the lubricity of the 0W30 oil, as well as to the tribological results. Then, under laboratory conditions, oil samples contaminated with up to 1 to 8% fuel were subjected to rheological (mini AV-X viscometer) and tribological (four-ball tester) tests. The dependence of the local pressure at the metal-to-metal contact point in the kinematic node on viscosity showed the dissimilar nature of the used and fresh oil and the divergence of the domains for the two groups of samples. Increasing the fuel contamination of used oil above 4% drastically reduces the pressure responsible for maintaining the oil film. In order to improve lubricant performance during HEV operation in urban conditions, it was proposed to carry out extra-urban traffic driving in order to evaporate the fuel from the engine oil. A shorter oil change interval is also recommended. Full article