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The potential of magnetic nanofluids as fracturing fluids in tight oil reservoir development is investigated. Hydrophobic magnetic nanoparticles (MNPs) are synthesized using a chemical co-precipitation method and characterized by Fourier transform infrared spectroscopy, dynamic light scattering, and scanning electron microscopy. A magnetic nanofluid is prepared as a pad fracturing fluid in accordance with the aforementioned methodology. Significantly, the effects of homogeneous and heterogeneous magnetic fields were evaluated on oil recovery and formation damage through core flooding experiments. The synthesized MNPs are hydrophobic, 20 nm in diameter, and stabilized by one layer of surfactant molecules in an aqueous solution. The nanofluid exhibits a relatively higher oil recovery than the surfactant solution because of its superior function of wettability alteration. The chaining behavior of MNPs under homogeneous magnetic fields leads to severe particle retention in the pore throats, which results in a significant decrease in core permeability. In contrast, the magnetic force gradient is unique to heterogeneous magnetic fields, resulting in a 40% increase in oil recovery at a magnetic intensity of 900 G near the core, while the permeability reduction is negligible. In conclusion, the retention of nanoparticles in pore throats represents a significant obstacle to the application of nanotechnology in tight reservoirs. The utilization of hydrophobic MNPs in conjunction with heterogeneous magnetic fields presents a potential solution to this conundrum. [ABSTRACT FROM AUTHOR]

Due to overexploitation and habitat loss, the Chinese pangolin (Manis pentadactyla) is in such extreme decline that it is so rare in the wild as to be considered functionally extinct, even in Guangdong, which was historically a major distribution area for the species. This study sought to verify whether functional extinction has occurred using observation records from field surveys, infrared wildlife cameras, rescue and enforcement cases and the published literature. The results indicated that suitable habitat occurred within 63.4% of the forested land in Guangdong, but only 17.6% of this area was deemed highly suitable, and 82.3% of all suitable habitat occurred outside of protected areas. Thus, the Chinese pangolin is not yet functionally extinct in Guangdong, but urgent conservation and restoration actions must be taken to ensure its persistence. Chinese pangolins in Guangdong Province are primarily distributed in the Lianhua Mountain and Nanling Mountains, with 91.6% belonging to a single population. From 1980 to 2020, the urban area increased by 776 km2, largely via conversion from agricultural land (48.6%). Suitable habitat for Chinese pangolins was reduced and became more fragmented over this time period, highlighting the urgent need for the establishment of protected areas, habitat restoration and cooperation with local residents. [ABSTRACT FROM AUTHOR]

This study provides an in-depth examination of gender differences in informal employment and its time evolution in Brazil, uses an LSTM model to quantitatively predict gender differences in informal employment and its evolution in Brazil, and explores the deeper reasons that lead to gender differences in informal employment based on labor market segmentation theory and gender role theory. The predictive analysis shows that Brazilian male and female informal employment will show a slight downward trend from the fourth quarter of 2023 to the third quarter of 2026, and that male informal employment is generally higher than that of females throughout the time series. In addition, market segmentation theory reveals that the structural segmentation of the informal employment market as a peripheral component of lower wages and social security affects the sexes differently, while gender role theory further expands on socio-cultural expectations of men's and women's behaviors and occupational choices, highlighting the reinforcement of gender differences by these structural barriers. Ultimately, the study makes policy recommendations to promote gender equality and improve the conditions of informal employment in support of the sustainable development goals. [ABSTRACT FROM AUTHOR]

Drop bruising is among the most common forms of mechanical damage to fruit during postharvest procedures. To minimize the damage inflicted on apples by free falling during harvesting, transportation and preservation processes and to better understand the mechanism of this damage, this paper investigates the area and contact pressure distribution of a drop bruise when an apple of a certain weight is dropped from a specific height onto a steel substrate. The characteristics of the contact pressure were measured using Prescale® pressure-sensitive film and subsequently analyzed to determine the relationship between the bruise area and the pressure distribution upon impact. Our findings indicate that the peak range of contact pressure stood between 0.5 and 0.6 MPa for an apple dropped from a height of 20-80 cm onto a steel substrate. The pressures displayed a fairly regular distribution with a relatively small pressure area, closely matching the bruised area. Additionally, the area with a pressure range of 0.2-0.4 MPa was found to be the largest, with an average pressure of 0.25-0.28 MPa. The pressure area showed a linear increase in correspondence with the increase in fruit weight and drop height, maintaining a consistent peak. The linear regression model, formulated using the product of the pressure area and average pressure, accurately predicts and assesses the bruised area of a dropped apple. This research could inform the design of mechanized and automated equipment aiming to reduce the frequency of bruising in apples. [ABSTRACT FROM AUTHOR]

Efforts have been made to streamline the abstract as follows. If further changes are made we are concerned that the integrity of the content may be compromised. We hope you will understand. This study aimed to investigate the impact damage experienced by Pucheng crisp pears during various stages, including harvest, transportation, and processing. Drop impact tests were conducted on pears, considering drop height and collision contact material as factors influencing damage. The bruise area was used as an indicator for damage evaluation. Additionally, the pressure-sensitive film technique was employed to measure the contact stress distribution characteristics of Pucheng crisp pears after the drop impact. The relationship between contact stress distribution and damage area was examined, and the stress area range close to the damage area was determined. The results revealed that the damage area of pears increased linearly with the increasing drop height. Among the four contact materials, foam board exhibited the best cushioning properties, with a maximum safe drop height of 20 cm. The pressure distribution tended to follow a normal distribution, with a pressure range of 0.2-0.3 MPa covering the largest area, corresponding to the majority of the bruise area on the pears. Furthermore, the pressure area and average pressure were found to be related to the severity of bruising. When pears were dropped onto steel, rubber plate and corrugated board, for the former two the stress area exceeding 0.2 MPa closely approximated the damage area, with an average relative error of 7.2%. For the latter, the closest range was above 0.3 MPa, with an average relative error of 3.6%. However, when dropped onto foam board, the average relative error was 75%. This research provides valuable insights for designing packaging tools to minimize damage and serves as a theoretical basis for predicting and assessing pear bruise area using finite element analysis. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) can cause cell injury and death via mitochondrial-dependent pathways, and supplementation with antioxidants has been shown to ameliorate these processes. The c-Jun N[H.sub.2]-terminal kinase (JNK) pathway has been shown to play a critical role in ROS-induced cell death. To determine if targeting catalase (CAT) to the mitochondria provides better protection than cytosolic expression against [H.sub.2][O.sub.2]-induced injury, the following two approaches were taken: 1) adenoviral-mediated transduction was performed using cytosolic (CCAT) or mitochondrial (MCAT) CAT cDNAs and 2) stable cell lines were generated overexpressing CAT in mitochondria (n = 3). Cells were exposed to 250 [micro]M [H.sub.2][O.sub.2], and cell survival, mitochondrial function, cytochrome c release, and JNK activity were analyzed. Although all viral transduced cells had a transient twofold increase in CAT activity, MCAT cells had significantly higher survival rates, the best mitochondrial function, and lowest JNK activity compared with CCAT and LacZ controls. The improved protection with MCAT was observed in primary type II lung epithelial cells and in transformed lung epithelial cells. In the three stable cell lines, cell survival directly correlated with extent of mitochondrial localization (r = 0.60572, P < 0.05) and not overall CAT activity (r = -0.45501, P < 0.05). Data indicate that targeting of antioxidants directly to the mitochondria is more effective in protecting lung epithelial cells against ROS-induced injury. This has important implications in antioxidant supplementation trials to prevent ROS-induced lung injury in critically ill patients. antioxidants; apoptosis; reactive oxygen species; c-Jun N[H.sub.2]-terminal kinase; c-Jun N[H.sub.2]-terminal kinase pathway

Prolonged exposure to supraphysiological oxygen concentrations results in the generation of reactive oxygen species, which can cause significant lung injury in critically ill patients. Supplementation with human recombinant antioxidant enzymes (AOE) may mitigate hyperoxic lung injury, but it is unclear which combination and concentration will optimally protect pulmonary epithelial cells. First, stable cell lines were generated in alveolar epithelial cells (MLE12) overexpressing one or more of the following AOE: Mn superoxide dismutase (MnSOD), CuZnSOD, or glutathione peroxidase 1. Next, A549 cells were transduced with 50-300 particles/cell of recombinant adenovirus containing either LacZ or each of the three AOE (alone or in combination). Cells were then exposed to 95% [O.sub.2] for up to 3 days, with cell number and viability determined daily. Overexpression of either MnSOD (primarily mitochondrial) or CuZnSOD (primarily cytosolic) reversed the growth inhibitory effects of hyperoxia within the first 48 h of exposure, resulting in a significant increase in viable cells (P < 0.05), with 1.5- to 3-fold increases in activity providing optimal protection. Protection from mitochondrial oxidation was confirmed by assessing aconitase activity, which was significantly improved in cells overexpressing MnSOD (P < 0.05). Data indicate that optimal protection from hyperoxic injury occurs in cells coexpressing MnSOD and glutathione peroxidase 1, with prevention of mitochondrial oxidation being a critical factor. This has important implications for clinical trials in preterm infants receiving SOD supplementation to prevent acute and chronic lung injury. viral transduction: gene therapy; adenovirus; antioxidants

Bacterial infection of the tracheobronchial tree is a frequent, serious complication in patients receiving treatment with oxygen and mechanical ventilation, resulting in increased morbidity and mortality. Using human airway epithelial cell culture models, we examined the effect of hyperoxia on bacterial adherence and the expression of interleukin-8 (IL-8), an important mediator involved in the inflammatory process. A 24-h exposure to 95% 02 increased Pseudomonas aeruginosa (PA) adherence 57% in A549 cells (P < 0.01) and 115% in 16HBE cells (P < 0.01) but had little effect on Staphylococcus aureus (SA) adherence. Exposure to hyperoxia, followed by a 1-h incubation with SA, further enhanced PA adherence (P < 0.01), suggesting that hyperoxia and SA colonization may enhance the susceptibility of lung epithelial cells to gram-negative infections. IL-8 expression was also increased in cells exposed to both hyperoxia and PA. Stable or transient overexpression of manganese superoxide dismutase reduced both basal and stimulated levels of PA adherence and IL-8 levels in response to exposure to either hyperoxia or PA. These data indicate that hyperoxia increases susceptibility to infection and that the pathways are mediated by reactive oxygen species. Therapeutic intervention strategies designed to prevent accumulation of intracellular reactive oxygen species may reduce opportunistic pulmonary infections. bacteria; inflammation; cytokines; antioxidants; adenovirus