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BACKGROUND: Epimedin A (EA) has been shown to suppress extensive osteoclastogenesis and bone resorption, but the effects of EA remain incompletely understood. The aim of our study was to investigate the effects of EA on osteoclastogenesis and bone resorption to explore the corresponding signalling pathways. METHODS: Rats were randomly assigned to the sham operation or ovariectomy group, and alendronate was used for the positive control group. The therapeutic effect of EA on osteoporosis was systematically analysed by measuring bone mineral density and bone biomechanical properties. In vitro, RAW264.7 cells were treated with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) to induce osteoclast differentiation. Cell viability assays, tartrate-resistant acid phosphatase (TRAP) staining, and immunofluorescence were used to elucidate the effects of EA on osteoclastogenesis. In addition, the expression of bone differentiation-related proteins or genes was evaluated using Western blot analysis or quantitative polymerase chain reaction (PCR), respectively. RESULTS: After 3 months of oral EA intervention, ovariectomized rats exhibited increased bone density, relative bone volume, trabecular thickness, and trabecular number, as well as reduced trabecular separation. EA dose-dependently normalized bone density and trabecular microarchitecture in the ovariectomized rats. Additionally, EA inhibited the expression of TRAP and NFATc1 in the ovariectomized rats. Moreover, the in vitro results indicated that EA inhibits osteoclast differentiation by suppressing the TRAF6/PI3K/AKT/NF-κB pathway. Further studies revealed that the effect on osteoclast differentiation, which was originally inhibited by EA, was reversed when the TRAF6 gene was overexpressed. CONCLUSIONS: The findings indicated that EA can negatively regulate osteoclastogenesis by inhibiting the TRAF6/PI3K/AKT/NF-κB axis and that ameliorating ovariectomy-induced osteoporosis in rats with EA may be a promising potential therapeutic strategy for the treatment of osteoporosis.
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Diferenciación Celular , FN-kappa B , Osteoclastos , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Factor 6 Asociado a Receptor de TNF , Animales , Factor 6 Asociado a Receptor de TNF/metabolismo , Factor 6 Asociado a Receptor de TNF/genética , Osteoclastos/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Femenino , Fosfatidilinositol 3-Quinasas/metabolismo , Ratas , Ratones , Células RAW 264.7 , Flavonoides/farmacología , Osteogénesis/efectos de los fármacos , Ratas Sprague-Dawley , Osteoporosis/metabolismo , Osteoporosis/etiología , Ovariectomía/efectos adversos , Regulación de la Expresión Génica/efectos de los fármacos , Densidad Ósea/efectos de los fármacosRESUMEN
In recent years, as the abundance of residual mulch film (RMF) in agricultural soil continues to increase, whether the adsorption capacity of its surface affects the migration of heavy metals is a topic of current interest for scholars. Herein, this study investigated the distribution of RMF abundance and metal concentration in different soil layers of 75 plastic-mulching croplands in subtropical China; meanwhile, we also explored the associations of RMF characteristics with metal concentration. The results showed that land type, film mulching amount, and film mulching time were the main factors affecting RMF abundance, distribution, and particle size composition. The highest abundance of RMF was found in the garden soils (910 n·kg-1) with more than 15 years mulching period and more than 19.5 kg hm-2 of annual mulch amount. The lowest abundance of RMF was occurred in the group of field and conservation agricultural land (237 n·kg-1). Moreover, the concentrations of metals in soil, especially Cd, Cr, Cu, and Pb, were closely related to the extent of RMF contamination in the soil environment. In the 0-10 cm and 10-20 cm soil layers, microplastic abundance exhibited a negative correlation with Cr and Cu concentrations and a positive correlation with Pb concentration. Based on the above findings, it is demonstrated that RMF significantly influences the mobility of metals in soil via adsorption processes, with potential synergistic effects between RMF and heavy metals posing a heightened risk to the soil environment.
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Hollow CuS nanoparticles can achieve photothermal and photodynamic therapy (PDT) in tumor treatment. However, excessive GSH in the tumor cells will consume the reactive oxygen species produced by PDT and reduce the PDT effect. Cisplatin is a broad-spectrum antineoplastic drug that can be used in a variety of tumor treatments. However, cisplatin is cytotoxic to normal cells while it kills tumor cells. Therefore, we construct Pt(IV) complexes loaded hollow CuS nanoparticles to attenuate the toxicity of cisplatin and enhance the PDT effect of the hollow CuS nanoparticles. The nanoparticles were proved to be able to accumulate around the tumor site through the enhanced permeability and retention (EPR) effect to achieve a synergistic chemo/photothermal/photodynamic therapy.
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Antineoplásicos , Cobre , Nanopartículas , Fotoquimioterapia , Cobre/química , Cobre/farmacología , Nanopartículas/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Animales , Cisplatino/farmacología , Cisplatino/química , Ratones , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Platino (Metal)/química , Platino (Metal)/farmacología , Terapia Fototérmica , Supervivencia Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Sulfuros/química , Sulfuros/farmacología , Tamaño de la PartículaRESUMEN
Background: Managing adult degenerative lumbar scoliosis (ADLS) presents a complex challenge, requiring advanced, minimally invasive surgical techniques. Objective: This study aims to evaluate and compare the efficacy and outcomes of oblique lateral interbody fusion (OLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in treating ADLS, with an emphasis on surgical methods, recovery times, and spinal correction results. Methods: We reviewed 42 patients with ADLS who did not respond to conservative treatments. These patients underwent either OLIF or MIS-TLIF procedures. Key factors analyzed included surgical duration, blood loss, complications, and changes in preoperative and postoperative lumbar lordosis (LL), anterior and posterior disc height (ADH, PDH), and Cobb angles. Statistical analysis was conducted using SPSS software, with significance determined at p < 0.05. Results: The OLIF technique showed notable benefits in multi-segment spinal corrections, particularly in enhancing intervertebral disc height and correcting Cobb angles. While both surgical methods effectively addressed spinal deformities, OLIF was less invasive, resulting in reduced blood loss, shorter surgery times, and fewer complications. No significant differences were found between the two techniques for single-segment corrections. Conclusion: For multi-segment spinal corrections in ADLS, OLIF is a superior choice due to its minimal invasiveness and favorable recovery profile. However, for patients with primarily radicular symptoms and no significant postural alterations, MIS-TLIF may be more appropriate.
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CD4+ T cells are central mediators of protective immunity to blood-stage malaria, particularly for their capacity in orchestrating germinal center reaction and generating parasite-specific high-affinity antibodies. T follicular helper (Tfh) cells are predominant CD4+ effector T cell subset implicated in these processes, yet the factors and detailed mechanisms that assist Tfh cell development and function during Plasmodium infection are largely undefined. Here we provide evidence that receptor for activated C kinase 1 (RACK1), an adaptor protein of various intracellular signals, is not only important for CD4+ T cell expansion as previously implied but also plays a prominent role in Tfh cell differentiation and function during blood-stage Plasmodium yoelii 17XNL infection. Consequently, RACK1 in CD4+ T cells contributes significantly to germinal center formation, parasite-specific IgG production, and host resistance to the infection. Mechanistic exploration detects specific interaction of RACK1 with STAT3 in P. yoelii 17XNL-responsive CD4+ T cells, ablation of RACK1 leads to defective STAT3 phosphorylation, accompanied by substantially lower amount of STAT3 protein in CD4+ T cells, whereas retroviral overexpression of RACK1 or STAT3 in RACK1-deficient CD4+ T cells greatly restores STAT3 activity and Bcl-6 expression under the Tfh polarization condition. Further analyses suggest RACK1 positively regulates STAT3 stability by inhibiting the ubiquitin-proteasomal degradation process, thus promoting optimal STAT3 activity and Bcl-6 induction during Tfh cell differentiation. These findings uncover a novel mechanism by which RACK1 participates in posttranslational regulation of STAT3, Tfh cell differentiation, and subsequent development of anti-Plasmodium humoral immunity.
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Diferenciación Celular , Malaria , Plasmodium yoelii , Receptores de Cinasa C Activada , Factor de Transcripción STAT3 , Células T Auxiliares Foliculares , Animales , Receptores de Cinasa C Activada/metabolismo , Factor de Transcripción STAT3/metabolismo , Malaria/inmunología , Malaria/parasitología , Ratones , Plasmodium yoelii/inmunología , Células T Auxiliares Foliculares/inmunología , Células T Auxiliares Foliculares/metabolismo , Ratones Endogámicos C57BL , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Ratones Noqueados , Centro Germinal/inmunologíaRESUMEN
Piezoelectric atomization is becoming mainstream in the field of inhalation therapy due to its significant advantages. With the rapid development of high-viscosity gene therapy drugs, the demand for piezoelectric atomization devices is increasing. However, conventional piezoelectric atomizers with a single-dimensional energy supply are unable to provide the energy required to atomize high-viscosity liquids. To address this problem, our team has designed a flow tube internal cavitation atomizer (FTICA). This study focuses on dissecting the atomization mechanism of FTICA. In contrast to the widely supported capillary wave hypothesis, our study provides evidence in favor of the cavitation hypothesis, proving that cavitation is the key to atomizing high-viscosity liquids with FTICA. In order to prove that the cavitation is the key to atomizing in the structure of FTICA, the performance of atomization is experimented after changing the cavitation conditions by heating and stirring of the liquids.
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Coastal hypoxia (low dissolved oxygen in seawater) is a cumulative result of many physical and biochemical processes. However, it is often difficult to determine the key drivers of hypoxia due to the lack of frequent observational oceanographic and meteorological data. In this study, high-frequency time-series observational data of dissolved oxygen (DO) and related parameters in the coastal waters of Muping, China, were used to analyze the temporal pattern of hypoxia and its key drivers. Two complete cycles with the formation and destruction of hypoxia were captured over the observational period. Persistent thermal stratification, high winds and phytoplankton blooms are identified as key drivers of hypoxia in this region. Hypoxia largely occurs due to persistent thermal stratification in summer, and hypoxia can be noticeably relieved when strong wind mixing weakens thermal stratification. Furthermore, we found that northerly high winds are more efficient at eroding stratification than southerly winds and thus have a greater ability to relieve hypoxia. This study revealed an episodic hypoxic event driven by a phytoplankton bloom that was probably triggered by terrestrial nutrient loading, confirming the causal relationship between phytoplankton blooms and hypoxia. In addition, we found that the lag time between nutrient loading, phytoplankton blooms and hypoxia can be as short as one week. This study could help better understand the development of hypoxia and forecast phytoplankton and hypoxia, which are beneficial for aquaculture in this region.
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Monitoreo del Ambiente , Eutrofización , Oxígeno , Fitoplancton , Agua de Mar , China , Fitoplancton/fisiología , Agua de Mar/química , Oxígeno/análisis , Viento , Estaciones del AñoRESUMEN
Chromatographic separation processes are most often modeled in the form of partial differential equations (PDEs) to describe the complex adsorption equilibria and kinetics. However, identifying parameters in such a model requires substantial computational effort. In this work, a novel parameter estimation approach using a Physics-informed Neural Network (PINN) model is developed and tested for a binary component system. Numerical accuracy of our PINN model is confirmed by validating its simulations against those of the finite element method (FEM). Furthermore, model parameters in the kinetic model are estimated by the PINN model with sufficient accuracy from the observed data at the column outlet, where parameter fitting error can be reduced by up to 35.0 % from the conventional method. In a comparison with the conventional numerical method, our approach can reduce the computational time by up to 95 %. The robustness of the PINN model has also been demonstrated by estimating model parameters from noisy artificial experimental data.
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Redes Neurales de la Computación , Cinética , Adsorción , Análisis de Elementos Finitos , Simulación por Computador , Modelos Químicos , Algoritmos , Cromatografía/métodosRESUMEN
In recent years, with the rapid development of network applications and the increasing demand for high-quality network service, quality-of-service (QoS) routing has emerged as a critical network technology. The application of machine learning techniques, particularly reinforcement learning and graph neural network, has garnered significant attention in addressing this problem. However, existing reinforcement learning methods lack research on the causal impact of agent actions on the interactive environment, and graph neural network fail to effectively represent link features, which are pivotal for routing optimization. Therefore, this study quantifies the causal influence between the intelligent agent and the interactive environment based on causal inference techniques, aiming to guide the intelligent agent in improving the efficiency of exploring the action space. Simultaneously, graph neural network is employed to embed node and link features, and a reward function is designed that comprehensively considers network performance metrics and causality relevance. A centralized reinforcement learning method is proposed to effectively achieve QoS-aware routing in Software-Defined Networking (SDN). Finally, experiments are conducted in a network simulation environment, and metrics such as packet loss, delay, and throughput all outperform the baseline.
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BACKGROUND: Depressive episodes in adolescents are often accompanied by various physical symptoms, but few studies have explored the association between depression and fever, This case study is the first to report the relationship between unexplained recurrent high fever and depression. CASE PRESENTATION: H is a 15 year old adolescent female currently in junior year. 2 + months ago, H gradually felt depressed after a class change. Around the time, the patient suddenly developed chills with no obvious trigger and fever. H was treated with anti-infective and anti-viral treatments all of which did not show significant improvement. No significant abnormality was seen in any of the related examinations. Considering that the patient's anxiety, depression and somatic symptoms were obvious during the course of the disease, she was given venlafaxine hydrochloride extended-release capsule 75 mg/d; tandospirone citrate capsule 10 mg Bid; alprazolam tablets 0.4 mg qn to improve mood and sleep; supplemented with transcranial repetitive magnetic stimulation therapy 2 times/d; visible light therapy 1 time/d and psychological counseling once. Over the 6 days of treatment, the patient's body temperature gradually returned to the normal range and her mood improved significantly. CONCLUSION: Depression should be considered a potential cause of unexplained recurrent fevers in adolescents, even when the temperature is significantly outside the normal range.
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Psicoterapia , Humanos , Adolescente , Femenino , Clorhidrato de Venlafaxina/uso terapéuticoRESUMEN
BACKGROUND AND OBJECTIVES: Long-term pathological myocardial hypertrophy (MH) seriously affects the normal function of the heart. Dronedarone was reported to attenuate left ventricular hypertrophy of mice. However, the molecular regulatory mechanism of dronedarone in MH is unclear. METHODS: Angiotensin II (Ang II) was used to induce cell hypertrophy of H9C2 cells. Transverse aortic constriction (TAC) surgery was performed to establish a rat model of MH. Cell size was evaluated using crystal violet staining and rhodamine phalloidin staining. Reverse transcription quantitative polymerase chain reaction and western blot were performed to detect the mRNA and protein expressions of genes. JASPAR and luciferase activity were conducted to predict and validate interaction between forkhead box O3 (FOXO3) and protein kinase inhibitor alpha (PKIA) promoter. RESULTS: Ang II treatment induced cell hypertrophy and inhibited sirtuin 1 (SIRT1) expression, which were reversed by dronedarone. SIRT1 overexpression or PKIA overexpression enhanced dronedarone-mediated suppression of cell hypertrophy in Ang II-induced H9C2 cells. Mechanistically, SIRT1 elevated FOXO3 expression through SIRT1-mediated deacetylation of FOXO3 and FOXO3 upregulated PKIA expression through interacting with PKIA promoter. Moreover, SIRT1 silencing compromised dronedarone-mediated suppression of cell hypertrophy, while PKIA upregulation abolished the influences of SIRT1 silencing. More importantly, dronedarone improved TAC surgery-induced MH and impairment of cardiac function of rats via affecting SIRT1/FOXO3/PKIA axis. CONCLUSIONS: Dronedarone alleviated MH through mediating SIRT1/FOXO3/PKIA axis, which provide more evidences for dronedarone against MH.
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The investigation into the spectral properties and refractive index (RI) sensitivities at low RI region of helical intermedium-period fiber gratings (HIPFGs) with varied periods ranging from 10-48â µm is presented in detail for the first time. The structure of HIPFG is optimized for RI sensing in the RI range of 1.3-1.33 by comparing the optical properties of HIPFGs with different grating periods. The HIPFG with optimized structure is demonstrated to have a high average sensitivity of 302.5â nm/RIU in the RI ranging from 1.3 to 1.33, which is two orders more elevated than the traditional long-period fiber gratings. The improved HIPFG is also experimentally applied to breath monitoring in different states. Normal breath, slow breath, fast breath, and unhealthy breath are distinguished based on breathing rate, intensity, and time of exhalation and inhalation. The fastest response time is determined to be 10â ms. The results demonstrate that the optical fiber's sensitivity in the low RI region can be increased by shortening its period, offering a special strategy for improving detection performance of HIPFGs. By verifying its performance in breathing monitoring, it is proved that the optimized HIPFG sensor has the great potential to expand medical applications.
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The performance of the heavy-duty escalator truss greatly affects the stability and service life of the whole escalator system, and the manufacturing cost of truss structure accounts for more than 1/5. Thus, how to design the truss structure reasonably is a pivotal issue drawing the attention of numerous engineers and researchers. In this work, the experimental research of heavy-duty escalators under full load conditions were performed in terms of the end restraints, the docking port clearances, and the deflection. Based on the experimental results, the three-dimensional simulation model of truss structure was created, and the influences of various factors such as the internal chamfer of truss member, the lower deviation of truss member, the dead weight of escalator, and the pretension force of each bolt at the docking port were analyzed and quantified. Finally, the finite element model which can almost completely characterize the actual structure was obtained with slight difference. The conclusions drawn in this work provide the basis for the efficient design, correct simulation, low cost production and rapid installation of the heavy-duty escalator truss.
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BACKGROUND: The formation of sandwiched vertebrae (SDVs) after percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) has become a common phenomenon. Whether SDVs are more likely to fracture is still controversial. Therefore, we conducted a meta-analysis to provide medical evidence for whether SDVs are more prone to refracture than non-SDVs (NSDVs) after PVP or PKP. METHODS: This study was conducted in accordance with the criteria of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Several databases, including PubMed, Embase, Medline databases, China National Knowledge Infrastructure, Wanfang, and Weipu, were thoroughly searched for relevant studies included from any point up until June 2022. Statistical analyses were performed using Revman 5.4. RESULTS: A total of 4052 individuals from 9 studies were enrolled. Overall, patients with SDV presented more risk to have refracture than patients with NSDV (OR = 1.57, P = 0.04). The incidences of refracture were comparable between the 2 cohorts in studies with a follow-up time less than 3 years (OR = 1.28, P = 0.49). However, patients with SDV were more prone to have refracture than patients with NSDV in studies with a follow-up time longer than 3 years (OR = 1.92, P = 0.009). Moreover, patients with SDV were more likely to have refracture than patients with NSDV in studies that involved both PVP and PKP (OR = 1.62, P = 0.002). In addition, age, low bone density, and postoperative kyphosis angle of sandwich fracture segments >10° were independent factors to predict refracture. CONCLUSIONS: Patients with SDV were more likely to have refracture after PVP or PKP, especially when the follow-up time was longer than 3 years.
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The release and deposition of phytoplankton-derived particulate organic matter is crucial in marine carbon export, yet the roles of picoplankton in these processes were seldom considered. Therefore, this study aimed to shed light on the matter by investigating the aggregating (AG) lifestyle of Synechococcus, a main group of picoplankton, in the coastal waters of the Yellow River Estuary with ample sediments acting as ballast minerals. We revealed that AG Synechococcus constituted a substantial portion, maximally reaching up to 85.4 %, of the total Synechococcus population. Pearson correlations and random forest (RF) regression analyses found significant connections (p < 0.01) between AG Synechococcus and the content of particulate organic carbon (POC), which emphasized its underlying role in facilitating POC export in this region. Furthermore, by employing high-throughput sequencing of the RNA polymerase gene (rpoC1), it was demonstrated that S5.1 clade I exhibited a significantly higher proportion in the AG fraction than in the free-living (FL) fraction (p < 0.05). This suggests distinct inclinations in the phylogenetic preference for different Synechococcus lineages between different lifestyles in the studied area. Finally, we ascertained "small-world" and higher robustness attributes of aggregates formed through the co-occurrence construction between Synechococcus and heterotrophic bacteria, likely facilitated by the reciprocal exchange of carbon and nitrogen elements. Overall, these findings have implications for our understanding of the role of Synechococcus in the ecology and biogeochemistry of marine ecosystems, and they are significant for more accurately evaluating the contribution of picophytoplankton in ocean carbon export.
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Synechococcus , Carbono/análisis , Ecosistema , Filogenia , Estuarios , Material Particulado , Agua de Mar/microbiologíaRESUMEN
Emerging data suggest that induction of viral mimicry responses through activation of double-stranded RNA (dsRNA) sensors in cancer cells is a promising therapeutic strategy. One approach to induce viral mimicry is to target molecular regulators of dsRNA sensing pathways. Here, we show that the exoribonuclease XRN1 is a negative regulator of the dsRNA sensor protein kinase R (PKR) in cancer cells with high interferon-stimulated gene expression. XRN1 deletion causes PKR pathway activation and consequent cancer cell lethality. Disruption of interferon signaling with the JAK1/2 inhibitor ruxolitinib can decrease cellular PKR levels and rescue sensitivity to XRN1 deletion. Conversely, interferon-ß stimulation can increase PKR levels and induce sensitivity to XRN1 inactivation. Lastly, XRN1 deletion causes accumulation of endogenous complementary sense/anti-sense RNAs, which may represent candidate PKR ligands. Our data demonstrate how XRN1 regulates PKR and how this interaction creates a vulnerability in cancer cells with an activated interferon cell state.
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Interferones , Neoplasias , Interferón beta , Exorribonucleasas/metabolismo , Proteínas Quinasas , Neoplasias/genéticaRESUMEN
Diabetes mellitus (DM) is a chronic metabolic disease characterized by elevated blood glucose levels, resulting in multi-organ dysfunction and various complications. Fusion proteins can form multifunctional complexes by combining the target proteins with partner proteins. It has significant advantages in improving the performance of the target proteins, extending their biological half-life, and enhancing patient drug compliance. Fusion protein-based drugs have emerged as promising new drugs in diabetes therapeutics. However, there has not been a systematic review of fusion protein-based drugs for diabetes therapeutics. Hence, we conducted a comprehensive review of published literature on diabetic fusion protein-based drugs for diabetes, with a primary focus on immunoglobulin G (IgG) fragment crystallizable (Fc) region, albumin, and transferrin (TF). This review aims to provide a reference for the subsequent development and clinical application of fusion protein-based drugs in diabetes therapeutics.
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In this paper, a low-temperature thick oil demulsifier with high polarity was prepared by introducing ethylene oxide, propylene oxide block, and butylene oxide using m-diphenol as a starting agent. The main reasons for the difficulty involved in the low-temperature emulsification of extractive fluids were explained by analyzing the synthetic influencing factors and infrared spectra of the star comb polymer (PR-D2) and by analyzing the four fractions, interfacial energies, and zeta potentials of crude oils from the Chun and Gao fields. The effects of PR-D2 surfactant on the emulsification performance of crude oil recovery fluids were investigated via indoor and field experiments. The experimental results indicate that the optimal synthesis conditions for this emulsion breaker are as follows: a quality ratio of ionic reaction intermediates and meso-diphenol of R = 10:1; 1 g of the initiator; a polymerization temperature of 80 °C; and a reaction time of 8 h. Colloidal asphaltenes in the crude oil were the main factor hindering the low-temperature demulsification of the Gao oilfield's extractive fluids, and the reason for the demulsification difficulty of the extractive fluids in the Chun oilfield is that the temperature of demulsification is lower than the wax precipitation point. The demulsification rate of the Chun oilfield's extractive fluids reached more than 98% when the PR-D2 concentration reached 150 mg/L at 43 °C. The demulsification rate of the Gao oilfield's extractive fluids reached more than 98% at a PR-D2 concentration of 150 mg/L at 65 °C. The field experiments show that the Chun oilfield's extractive fluids can still demulsify after the temperature is reduced to 43 °C in winter. The emulsification temperature of the Gao oilfield's extractive fluids was reduced from 73 °C to 68 °C, with an excellent demulsification effect.
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Focusing on the problem of poor demulsification performance of light crude oil emulsions in low-permeability oilfields at low temperatures, the composition of the emulsion samples, clay particle size distribution, and the viscosity-temperature relationship curve of samples were analyzed. Based on the results of emulsion composition analysis and characteristics, the bottle test method was used to analyze the demulsifying effect of different commercial types of demulsifiers, revealing the demulsification mechanism. The field tests confirm the demulsification capabilities of Polyoxyethylene polyoxypropylene quaternized polyoxyolefins surfactants (PR demulsifiers). The results reveal that PR demulsifiers combine the features of decreasing the interfacial tension between oil and water and adsorbing SiO2, allowing for quick demulsification and flocculation at low temperatures. This research serves as a theoretical and practical foundation for the study and advancement of low-temperature demulsification technology in oilfields.