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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]

Study Question: What are the features of FAM71D (Family with sequence similarity 71, member D) expression and is there an association between FAM71D expression and sperm motility?Summary Answer: FAM71D, a novel protein exclusively expressed in the testis, is located in sperm flagella and is functionally involved in sperm motility.What Is Known Already: Some testis-specific proteins have been reported as potential diagnostic biomarkers to evaluate the spermatogenesis process and sperm quality. We have identified a novel testis-specific protein, FAM71D, through microarray data analysis, yet little is known about its expression and function.Study Design, Size, Duration: FAM71D mRNA and protein expression was quantified during mouse testis development. Its localization in germ cells was detected by dual-labeled immunostaining in testis sections and sperm smears. The clinical significance was assessed by comparing FAM71D expression in spermatozoa from normozoospermic controls and asthenozoospermic patients.Participants/materials, Setting, Methods: Testes were dissected from C57BL/6 J male mice at postnatal ages of 1, 2, 3, 4, 6, 8 weeks and 6 months, and sperm was collected from cauda epididymides of adult mice by the swim-up method. Human spermatozoa were isolated from 100 human semen samples by density gradient Percoll centrifugation. RT-qPCR and western blot were performed to semi-quantify the expression of FAM71D in mouse testis, and in the ejaculated spermatozoa of normozoospermic controls and asthenozoospermic patients. Immunofluorescence staining was used to detect the localization of FAM71D. Co-immunoprecipitation assay was performed to evaluate the interaction between FAM71D and calmodulin. An antibody blocking assay was employed to assess the role of FAM71D in sperm motility.Main Results and the Role Of Chance: Our results showed that FAM71D was exclusively expressed in the testis in an age-dependent manner. FAM71D expression exhibited dynamic change in the cytoplasm of spermatids during spermiogenesis and was finally retained in sperm flagella. FAM71D could interact with calmodulin. Use of anti-FAM71D antibody on sperm significantly decreased sperm motility. Expression level of FAM71D was markedly reduced in the ejaculated spermataozoa of asthenozoospermic patients (P < 0.05), and this was correlated with sperm progressive motility (r = 0.7435, P < 0.0001).Large Scale Data: N/A.Limitations, Reasons For Caution: The sample size was limited and it is necessary to verify the correlation of FAM71D expression with sperm motility in larger cohorts. Furthermore, our results were descriptive and follow-up studies would be needed to elucidate the detailed role of FAM71D in sperm motility.Wider Implications Of the Findings: This is the first systematic study to document the expression of endogenous FAM71D and a function for FAM71D in sperm motility. It provides new insights into our understanding of sperm motility regulation and causes of male infertility.Study Funding/competing Interests: This study was funded by the National Natural Science Foundation of China, Guangdong Natural Science Foundation and the Shenzhen Project of Science and Technology. The authors have no competing interests. [ABSTRACT FROM AUTHOR]

Clear cell renal cell carcinoma (ccRCC) is the predominant and most aggressive type of kidney malignancy, however, the mechanism underlying its carcinogenesis remains to be elucidated. The present study aimed to determine the expression and function of microRNA (miR)‑429 in ccRCC carcinogenesis. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to detect the expression of miR‑429 in ccRCC specimens. Following transfection of miR‑429 synthetic mimics, the expression of miR‑429 was examined and cell proliferation, cell migration, apoptosis and luciferase assays were conducted in ccRCC cell lines. The results demonstrated that expression of miR‑429 was decreased in ccRCC cells. In addition, upregulation of miR‑429 by transfection of mimics reduced cellular proliferation and migration, and induced apoptosis in ACHN and 786‑0 cell lines. Furthermore, miR‑429 decreased the 3'UTR luciferase activity of vascular endothelial growth factor (VEGF) and c‑MYC, and RT‑qPCR analysis demonstrated that the cancer cells transfected with miR‑429 mimics exhibited decreased expression of VEGF, but not c‑MYC. To the best of our knowledge, the present study was the first to reveal that downregulated miR‑429 functioned as a tumor suppressor by restraining cellular proliferation and migration, and inducing apoptosis, as well as targeting VEGF in ccRCC cells.

Renal cell carcinoma (RCC) is the most common type of renal tumor, which has a poor prognosis. Improvements in understanding the underlying molecular biology of RCC has led to systemic treatments, which have markedly improved patient outcomes. Therefore, it is necessary and worthwhile to identify novel biomarkers for RCC. MicroRNAs (miRNAs) have been found to be important in a wide range of biological and pathological processes, including cell differentiation, migration, growth, proliferation, apoptosis and metabolism. Aberrant expression of miRNA‑130b has previously been reported in tumors, however, its role in RCC remains to be elucidated. In the present study, the upregulation of miR‑130b was observed in RCC tissues and cell lines using reverse transcription‑quantitative polymerase chain reaction analysis, which was consistent with previous microRNA profiling in RCC. Furthermore, the effects of miR‑130b on cell migration, proliferation and apoptosis were examined using a wound scratch assay, an MTT assay and flow cytometric analysis, respectively. The results demonstrated that the downregulation of miR‑130b by a synthesized inhibitor inhibited cell migration, suppressed cell proliferation and induced RCC cell apoptosis. The present study was the first, to the best of our knowledge, to suggest that miR‑130b may be a promising biomarker for diagnosis and a therapeutic target for the treatment of RCC. Further investigations are required to examine the roles and target genes of miR‑130b in RCC.

Kidney cancer is the 14th most common cancer in the world and its prognosis remains poor due to difficult early detection and treatment. Therefore, the identification of biomarkers for early-stage renal cell carcinoma (RCC) is important. MicroRNA-106b (miR-106b) has been described as an oncogene in several types of human cancer. Previous microarray studies have suggested that miR-106b was significantly upregulated in RCC tissues compared with paired normal kidney tissues and may be a promising biomarker for the prediction of early metastasis following nephrectomy. The present study aimed to determine the expression and function of miR-106b in RCC. The expression of miR-106b in RCC tissues and cells, and in paired normal tissues and cells was determined by reverse transcription quantitative polymerase chain reaction, based on the previous sequencing results of miRNAs. Furthermore, a wound scratch assay, MTT assay and flow cytometry were performed to examine the functions of miR-106b on cell migration, proliferation and apoptosis. The results demonstrated that miR-106b was upregulated in RCC tissues and cell lines compared with control normal tissues and cell lines. Downregulation of miR-106b with a synthesized inhibitor suppressed cell migration and proliferation and induced renal cancer cell apoptosis, suggesting that miR-106b can be characterized as an oncogene in RCC. To the best of our knowledge, the present study was the first to reveal that miR-106b is upregulated and affects cellular migration, proliferation and apoptosis in RCC. Further studies are required to examine the role and target genes of miR-106b in RCC.

MicroRNAs (miRNAs/miRs) serve an important role in the regulation of carcinogenic pathways. RCC is the most prevalent kidney cancer that occurs in adults. miRNAs have gained increasing attention due to their association with RCC tumorigenesis, serving as biomarkers for early detection and progression monitoring, and as potential targets for molecular therapy. Upregulation of miRNA-142-3p has been previously identified in RCC tissues by microarray profile, however, its expression and function in RCC have not yet been validated. In the present study, quantitative polymerase chain reaction was performed to quantify the relative expression of miR-142-3p in 53 paired RCC and adjacent normal tissues. Furthermore, wound healing, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry assays were performed to analyze the impacts of miR-142-3p on cellular migration, proliferation and apoptosis. The results demonstrated that miR-142-3p was significantly upregulated in RCC tissues compared with adjacent normal tissues. Downregulation of miR-142-3p, induced by chemically synthesized miR-142-3p inhibitor, significantly suppressed cell migration and proliferation, and promoted cell apoptosis in 786-O and ACHN cells, supporting the theory that miR-142-3p may function as an oncogene in RCC. The potential clinical significance of miR-142-3p, as a biomarker and therapeutic target, provides rationale for further investigation into the miR-142-3p-mediated molecular pathway and how it is associated with RCC development.

Renal cell carcinoma (RCC) is the most common type of kidney cancer in adults and is associated with a poor prognosis due to a lack of early‑warning signs, protean clinical manifestations, and resistance to radiotherapy and chemotherapy. Recently, increasing evidence has suggested that microRNAs (miRNAs) are involved in the proliferation, invasion and apoptosis of various types of human cancer cells. In a previous study, miRNA expression profiles from renal cell carcinoma (RCC) revealed that expression of miR‑20b‑5p was significantly downregulated in RCC tissues. The aim of this study was to investigate the expression and functional significance of miR‑20b‑5p in RCC. The expression of miR‑20b‑5p was quantified in 48 paired RCC tissues and cell lines, and compared with adjacent normal tissues and the 293T cell line by reverse transcription‑quantitative polymerase chain reaction. The functional impact of miR‑20b‑5p on cell proliferation, cell migration and apoptosis in the 786‑O and ACHN RCC cell lines, was determined by an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, a scratch assay and flow cytometry. To the best of our knowledge, the present study was the first to reveal that miR‑20b‑5p was downregulated in RCC tissues and cell lines. It also demonstrated that upregulation of miR‑20b‑5p inhibited cellular migration and proliferation, and promoted cellular apoptosis, suggesting that miR‑20b‑5p functioned as a potential tumor suppressor. However, further studies are required to fully determine the effects of miR‑20b‑5p and the miR‑20b‑5p‑mediated molecular pathway in RCC and other types of cancer. In conclusion, these results imply that miR‑20b‑5p may be a biomarker for early detection and prognosis prediction, as well as a therapeutic target for RCC.

MicroRNAs (miRNAs) have been demonstrated to exhibit abnormal expression patterns in various types of human cancer. The aim of the present study was to identify a novel tumor suppressor microRNA (miR) and investigate its physiological function and mechanism in renal cell carcinoma (RCC). The expression levels of miRNA (miR)‑362‑3p expres were measured in 47 pairs of RCC and adjacent normal tissue samples, using reverse transcription-quantitative polymerase chain reaction analysis. In addition, miR‑362‑3p was transfected into renal cancer cells to investigate its role in the regulation of cell proliferation, migration, invasion, apoptosis and cell cycle. Identification of the target gene of miR‑362‑3p was performed using luciferase reporter assays and western blot analyses. The results demonstrated that the expression levels of miR‑362‑3p were downregulated in the RCC tissue samples, compared with the adjacent normal tissue samples. The upregulation of miR‑362‑3p using a synthesized mimic suppressed the proliferation, migration and invasion of the renal cancer cells, and induced cell apoptosis and G1 phase arrest. Further experiments demonstrated that the overexpression of miR‑362‑3p resulted in decrease expression levels of nemo-like kinase. These results suggested that miR-362-3p functions as a tumor suppressor in RCC, and may serve as a potential molecular target in the treatment of RCC.