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Hyperlipidemia is a chronic disease that is difficult to cure, and long-term pharmacotherapy may have negative consequences. Dietary therapy is a very promising strategy, and Chinese rice wine (Huangjiu) will play an important role because of its many biologically active components. In this work, the alleviating effect of Stachys sieboldii Miq. Huangjiu (CSCHJ) on high-fat diet-induced hyperlipidemia in mice was investigated, which is brewed from the wheat Qu with the addition of Stachys sieboldii Miq. and contains 15.54 g/L of polysaccharides. The experimental results showed that CSCHJ inhibited appetite, reduced body weight and blood sugar levels, and downregulated the serum levels of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) while concurrently upregulating high-density lipoprotein cholesterol (HDL-C) in the high-fat diet-induced hyperlipidemia mice. At the same time, it was discovered that alcohol worsens hyperlipidemia symptoms and related physiological markers, implying that CSCHJ polysaccharides may play a role in hyperlipidemia treatment. Through the assessment of organ indices, liver and kidney function, and tissue staining, CSCHJ demonstrated efficacy in repairing liver, kidney, and colon mucosal damage in hyperlipidemic mice. Furthermore, 16S rDNA sequencing and gas chromatography studies revealed that CSCHJ effectively restored the intestinal microbial structure and enhanced the quantity of fecal short-chain fatty acids (SCFAs) in hyperlipidemic mice. Therefore, the alleviating effect of CSCHJ on hyperlipidemia in mice may be attributed to its regulation of energy metabolism by repairing liver, kidney, and colon mucosal damage and restoring the gut microbiota structure, among other mechanisms. Overall, our findings provide evidence that CSCHJ contains active ingredients capable of alleviating hyperlipidemia, thereby laying a theoretical foundation for the extraction of bioactive substances from Huangjiu for future medical or dietary use.
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Surface sediment samples were collected from the surrounding sea areas of the two largest tourist islands in Sanya City, China, to compare and assess the sources, distribution, and ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs). The total PAHs concentrations ranged from 31.16 to 163.3 ng/g, with an average concentration of 102.46 ng/g, which is still lower than the levels detected in most other sediment studies worldwide. PAHs from coal combustion (Flu, Pyr, Fl, Phe) showed positive correlations with TOC, Silt, and Clay, indicating that these PAHs are easily adsorbed in muddy and silty sediments. Sanya Bay is primarily composed of mud and silt, whereas Haitang Bay is mainly sandy. This corresponds to the significantly higher concentrations of Fl, Phe, and Pyr in Sanya Bay compared to Haitang Bay. The main industrial activities in the study area are related to power and heat production and supply. The results indicate that the primary sources of sediment PAHs are high-temperature combustion during heavy industrial production, followed by maritime transportation and petroleum sources. Overall, the PAHs pollution levels in the study area range from slight to moderate. Sediment quality assessments show that only Ace and Phe have higher individual risk values. Six stations in Sanya Bay have higher adverse impact risks, while in Haitang Bay, only HT07 poses a high risk to biological impact. These two areas require enhanced monitoring and pollution source control.
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Background: Breast cancer (BC) has the highest incidence rate among female malignant tumors. Adjuvant chemotherapy is commonly used to reduce micrometastasis in postoperative patients. However, monitoring the efficacy of chemotherapy in BC is a major challenge in clinical practice. In this study, 1H nuclear magnetic resonance (NMR) metabonomics was performed to explore the serum metabolic characteristics of BC patients before and after adjuvant chemotherapy. Methods: In this study, we collected serum samples from 51 healthy controls and 61 BC patients before and after chemotherapy for 1H NMR metabolomic analysis, and tested the performance of each metabolite and combination segment by the receiver operating characteristic (ROC) curves. Results: Nine metabolites, namely glutamine, citrate, creatine, glycerophosphatidylcholine/phosphatidylcholine, glycine, 1-methylhistidine, lactate, pyruvate and formate had significant changes in BC patients before chemotherapy compared with healthy controls. Lactate, pyruvate, 1-methylhistidine and formate were found to be inversely regulated by chemotherapy. ROC analysis showed that a combination of the four metabolites had good prediction for chemotherapy efficacy with area under the curve of 0.958, sensitivity of 98.36% and specificity of 91.30%. There was no significant correlation between chemotherapy-related metabolites and clinical indicators of cancer patients, indicating that they can be used to evaluate the chemotherapy efficacy of patients with different clinical indicators. Conclusions: Effectively, dynamic and non-invasive metabolic markers for the evaluation of the efficacy of chemotherapy were identified in this study.
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Respiratory syncytial virus (RSV) is the major cause of bronchiolitis and pneumonia in young children and the elderly. There are currently no approved RSV-specific therapeutic small molecules available. Using high-throughput antiviral screening, we identified an oral drug, the prenylation inhibitor lonafarnib, which showed potent inhibition of the RSV fusion process. Lonafarnib exhibited antiviral activity against both the RSV A and B genotypes and showed low cytotoxicity in HEp-2 and human primary bronchial epithelial cells (HBEC). Time-of-addition and pseudovirus assays demonstrated that lonafarnib inhibits RSV entry, but has farnesyltransferase-independent antiviral efficacy. Cryo-electron microscopy revealed that lonafarnib binds to a triple-symmetric pocket within the central cavity of the RSV F metastable pre-fusion conformation. Mutants at the RSV F sites interacting with lonafarnib showed resistance to lonafarnib but remained fully sensitive to the neutralizing monoclonal antibody palivizumab. Furthermore, lonafarnib dose-dependently reduced the replication of RSV in BALB/c mice. Collectively, lonafarnib could be a potential fusion inhibitor for RSV infection.
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Piridinas , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Proteínas Virales de Fusión , Humanos , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/genética , Piridinas/farmacología , Ratones , Animales , Virus Sincitial Respiratorio Humano/efectos de los fármacos , Virus Sincitial Respiratorio Humano/genética , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/antagonistas & inhibidores , Farnesiltransferasa/antagonistas & inhibidores , Farnesiltransferasa/genética , Antivirales/farmacología , Antivirales/química , Piperidinas/farmacología , Piperidinas/química , Ratones Endogámicos BALB C , Conformación Proteica , DibenzocicloheptenosRESUMEN
Understanding of characteristics and transport of perfluoroalkyl acids (PFAAs) in heterogeneous estuarine environments is limited. Furthermore, the role of suspended particles (SPS) in different layers remains unclear. This study explores the multiphase distribution process and mechanism of PFAAs controlled by SPS across surface and bottom layers in five small estuaries. Peaks in PFAA concentrations are consistently observed at strongly stratified sites. Concentrations of the PFAAs in both surface and bottom SPS decreased as the degree of mixing increased from strongly stratified levels to well-mixed levels. The water-SPS partitioning of some short-chain PFAAs (PFBS, PFHxA, and PFHpA) is influenced by environmental factors (pH, depth, temperature, and salinity) due to electrostatic interactions, while the sorption of some long-chain PFAAs (PFOA, PFOS, and PFNA) is controlled by SPS and dissolved organic carbon (OC), driven by hydrophobic interactions. Additionally, SPS dominates OC transport in estuarine systems, except in sandy sediment environments. SPS plays a dominant role in PFAA partitioning in both surface and bottom water-SPS systems (p < 0.05), and salinity only significantly affects PFBS in bottom layer (p < 0.01). These findings are critical for understanding the drivers of PFAA partitioning and the roles of SPS in different layers, underscoring the necessity of considering particle-associated PFAA fractions in future coastal environmental management.
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A chemselective catalyst-free three-component 1,3-dipolar cycloaddition has been described. The unique polycyclic THPI and THIQs were creatively employed as dipolarophiles, which led to the formation of functionalized ß-tetrahydrocarboline- and tetrahydroisoquinoline-fused spirooxindoles in 60-94% of yields with excellent diastereoselectivities (10: 1->99: 1 dr). This reaction not only realizes a concise THPI- or THIQs-based 1,3-dipolar cycloaddition, but also provides a practical strategy for the construction of two distinctive spirooxindole skeletons.
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Mangroves have received substantial attention for their pivotal role as ecological barriers between land and sea, owing to their capacity to effectively capture considerable quantities of terrestrial pollutants. Mangrove fragmentation has been a widespread global trend. There is limited information on the water quality status of these small scattered mangrove patches in coastal sub-developed areas, coupled with a paucity of efficient and intuitive assessment methodologies. To address this gap, the Water Quality Index (WQI) was introduced to evaluate the spatiotemporal characteristics of mangrove water quality. The major sources of pollution and anthropogenic activities that affect mangrove water quality were identified. The results revealed an average WQI value of 44.1 ± 13.3 for mangrove patches, consistently indicating a "low" water quality classification throughout all seasons. Both the size and natural conditions impact the water quality of mangroves. The large artificial patch (WQI: 56.4 ± 7.61) and the natural patch (WQI: 46.6 ± 13.6) exhibited relatively superior water quality, while the WQI value of a size-equivalent artificial patch compared with the natural patch is 38.6 ± 11.8. Aquaculture was the primary human activity that adversely affected the water quality of mangroves, and the potential sources of pollution were rainfall runoff and river discharge. These findings elucidate the unfavorable water quality characteristics and dominant pollution of fragmented mangroves, and validate the applicability of the WQI method for long-term evaluation of the water quality in mangrove patches. This study provides a basis for decision-making in water quality assessment and management of coastal wetlands and marine ecosystems. Scientific guidance to the management for mangrove protection and restoration was offered, such as regulating aquaculture activities, controlling non-point source pollution, implementing mangrove reforestation by using native species in historical mangrove sites.
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The coastal area was the major region receiving pollution from land-based sources into the sea. Perfluoroalkyl acids (PFAAs) in famous bays had aroused wide concern, but the importance of underdeveloped or small bays with notable levels of PFAAs were often neglected. Moreover, the roles of suspended sediment (SPS) and water column stratification on PFAA behaviors were unclear. In this study, PFAAs distribution in multiphase-multilayer in four underdeveloped bays (two urban bays and two island bays) were investigated. The urban bays not only had higher PFAA contamination but also posed a greater threat of short-chain PFAAs in water-SPS-sediment system than the island bays. The major source of PFAAs in water and SPS was domestic sewage in urban bays and was rainfall-runoff in island bays. Water column stratification with higher PFAA partition in water-SPS system in the surface layer than in the bottom layer was only found in the urban bays due to the higher human activity intensity. These provided new perspectives for managing emerging contaminants and establishing water quality criteria in the turbid coastal environment. The key role of SPS as a carrier offered possibilities to accurately differentiate the effects of dissolved and particulate PFAAs on bioavailability.
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Fluorocarburos , Contaminantes Químicos del Agua , Humanos , Bahías , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Fluorocarburos/análisis , Ríos , Sedimentos GeológicosRESUMEN
Background: Rituximab (RTX) is gaining increasing clinical acceptance in the treatment of primary membranous nephropathy (PMN), with demonstrated efficacy and safety. However, there are few clinical studies on RTX for PMN in Asian populations, especially in China. Methods: To observe and analyse the efficacy and safety of RTX treatment, 81 patients with PMN suffering from nephrotic syndrome (NS) were enrolled and divided into an initial therapy group, a conventional immunosuppressive therapy relapse group, and a conventional immunosuppressive therapy ineffective group according to their pre-RTX treatment background. Patients in each group were followed up for 12 months. The primary outcome was clinical remission at 12 months, and the secondary outcomes were safety and the occurrence of adverse events. Results: At 12 months, 65 of 81 (80.2%) patients achieved complete (n=21, 25.9%) or partial (n=44, 54.3%) remission after rituximab treatment. Thirty-two of 36 (88.9%) patients in the initial therapy group, 11 of 12 (91.7%) patients in the relapse group and 22 of 33 (66.7%) patients in the ineffective group achieved clinical remission. All 59 patients with positive anti-PLA2R antibodies showed a decreasing trend in antibody levels after RTX treatment, and 55 (93.2%) of them achieved antibody clearance (<20 U/mL). Logistic regression analysis showed that a high anti-PLA2R antibody titer (OR=0.993, P=0.032) was an independent risk factor for nonremission. Adverse events occurred in 18 (22.2%) patients, of which 5 (6.2%) were serious adverse events, and none were malignant or otherwise fatal. Conclusion: RTX alone can effectively induce remission PMN and maintain stable renal function. It is recommended as the first choice of treatment and is also effective in patients who relapse and have poor responses to conventional immunosuppressive therapy. Anti-PLA2R antibodies can be used as a marker for RTX treatment monitoring, and antibody clearance is necessary to achieve and improve the rates of clinical remission.
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Glomerulonefritis Membranosa , Humanos , Rituximab/efectos adversos , Estudios Retrospectivos , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Inmunosupresores/efectos adversos , Anticuerpos/uso terapéuticoRESUMEN
BACKGROUND: To investigate the clinical and kidney pathological features and prognosis of idiopathic membranous nephropathy (IMN) with kidney tubulointerstitial damage (TID). METHODS: Based on the presence or absence of kidney TID by kidney biopsy, 300 patients diagnosed with IMN were categorized into non-TID (TID-) and tubulointerstitial injury (TID+) groups. The clinical and pathological data were analyzed retrospectively. All patients were followed up for 6-24 months after treatment with glucocorticoids (GCs) combined with cyclophosphamide or GCs combined with calcineurin inhibitors (CNIs) to observe treatment effects on patient prognosis. RESULTS: The patients in the TID + group were older and more likely to be male. The 24-h urine protein, blood urea nitrogen, serum creatinine, cystatin C, ß2-microglobulin, and antiphospholipase A2 receptor antibody levels were higher than those in the TID - group and the pathological manifestations were more severe. After 1 year of follow-up, the overall response rate (complete response + partial response) in the TID + group was lower (66.67% vs. 80.89%, p = .022) than in the other. After combined GC and CNI therapy, the complete remission rate in the TID + group was significantly lower than that in the TID - group (13.79% vs. 35.46%, p = .022). The 24-h urine protein level was an independent risk factor for worsening kidney condition (p = .038). CONCLUSION: Patients with IMN with TID have more severe clinical manifestations and pathological damage and lower remission rates. IMN with TID is a risk factor for worsening kidney condition; however, it is not an independent risk factor.
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Glomerulonefritis Membranosa , Humanos , Masculino , Femenino , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/tratamiento farmacológico , Glomerulonefritis Membranosa/diagnóstico , Estudios Retrospectivos , Ciclofosfamida/uso terapéutico , Pronóstico , Glucocorticoides/uso terapéutico , Riñón/patología , Inmunosupresores/uso terapéuticoRESUMEN
Precise and accurate quantitation of important biomarkers is significant, especially in early-stage diseases diagnosis. To realized effective biosample preparation and trace-level biomarker detection, a microtrap-assisted microfluidic magnetic immunoassays (µMI) method was developed in this work. A microtrap was fabricated inside the straight microchannel of µMI device to help magnetic separation and concentration of immunocomplexes. These immunocomplexes were enriched in microtrap of µMI device to accomplish selective and sensitive biomarker detection. Horseradish peroxidase-labeled magnetic beads were employed to evaluate assay feasibility and microtrap effect on assay sensitivity. The microtrap-assisted µMI was then applied for model biomarkers detection. The limits of detection of µMI were 0.025 pg/mL for monocyte chemoattractant protein-1 (MCP-1) and 0.021 pg/mL for matrix metalloproteinase-9 (MMP-9), which corresponded up to 2014-fold sensitivity improvement compared to their standard microwell enzyme-linked immunosorbent assay (ELISA) results. In addition, the selectivity and reproducibility of microtrap-assisted µMI were confirmed. In clinical serum sample analysis, recoveries of 91.3%-106.7% with relative standard deviations less than 6.1% were obtained for MCP-1 and MMP-9, and method accuracy was verified by commercial ELISA kit. The developed µMI can accomplish ultratrace biomarker detection offering practical tool for laboratorial and clinical research.
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Metaloproteinasa 9 de la Matriz , Microfluídica , Reproducibilidad de los Resultados , Inmunoensayo/métodos , Biomarcadores , Ensayo de Inmunoadsorción Enzimática/métodos , Fenómenos MagnéticosRESUMEN
Steady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) have received significant attention owing to their high information transfer rate (ITR) and low training requirements. Previous SSVEP-based BCIs mostly adopt the stationary visual flickers where only a few studies have explored the effect of moving visual flickers on the SSVEP-BCI. In this study, a novel stimulus encoding method based on the simultaneous modulation of luminance and motion was proposed. We adopted the sampled sinusoidal stimulation method to encode the frequencies and phases of stimulus targets. In addition to luminance modulation, at the same time, visual flickers also moved horizontally towards right and left at different frequencies (i.e., 0, 0.2, 0.4, and 0.6 Hz) following a sinusoidal function. Accordingly, a nine-target SSVEP-BCI was built to evaluate the influence of motion modulation on the BCI performance. Filter bank canonical correlation analysis (FBCCA) approach was adopted to identify the stimulus targets. Offline experimental results of 17 subjects revealed that the system performance decreased with the increase of superimposed horizontal periodic motion frequency. Our online experimental results showed that the subjects achieved 85.00 ± 6.77 % and 83.15 ± 9.88 % accuracy for the superimposed horizontal periodic motion frequencies of 0 and 0.2 Hz, respectively. These results verified the feasibility of the proposed systems. In addition, the system with 0.2 Hz horizontal motion frequency provided the best visual experience for subjects. These results indicated that moving visual stimulus can provide an alternative option for SSVEP-BCIs. Furthermore, the proposed paradigm is expected to develop a more comfortable BCI system.
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The brain-computer interfaces (BCIs) based on steady-state visual evoked potential (SSVEP) have been extensively explored due to their advantages in terms of high communication speed and smaller calibration time. The visual stimuli in the low- and medium-frequency ranges are adopted in most of the existing studies for eliciting SSVEPs. However, there is a need to further improve the comfort of these systems. The high-frequency visual stimuli have been used to build BCI systems and are generally considered to significantly improve the visual comfort, but their performance is relatively low. The distinguishability of 16-class SSVEPs encoded by the three frequency ranges, i.e., 31-34.75 Hz with an interval of 0.25 Hz, 31-38.5 Hz with an interval of 0.5 Hz, 31-46 Hz with an interval of 1 Hz, is explored in this study. We compare classification accuracy and information transfer rate (ITR) of the corresponding BCI system. According to the optimized frequency range, this study builds an online 16-target high frequency SSVEP-BCI and verifies the feasibility of the proposed system based on 21 healthy subjects. The BCI based on visual stimuli with the narrowest frequency range, i.e., 31-34.5 Hz, have the highest ITR. Therefore, the narrowest frequency range is adopted to build an online BCI system. An averaged ITR obtained from the online experiment is 153.79 ± 6.39 bits/min. These findings contribute to the development of more efficient and comfortable SSVEP-based BCIs.
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BACKGROUND: This study aimed to explore the clinical efficacy of different treatment regimens for idiopathic membranous nephropathy (IMN). METHODS: Patients with IMN were retrospectively analyzed by dividing into two groups: glucocorticoids combined with cyclophosphamide group (GC + CYC) and glucocorticoids combined with calcineurin inhibitor group (GC + CNIs). After 1 year of treatment, those who found that the initial treatment was not effective were switched to another regimen. Patients continued to be followed up for at least 1 year to observe the treatment effects of different treatment regimens. RESULTS: This study found that the rate of complete and partial remission (CR + PR) in the GC + CYC and GC + CNIs groups was 76.19 vs. 82.63% after 1 year of follow-up (p > .05). In the GC + CYC and GC + CNIs groups, 27.78 and 11.95% of the patients switched treatment regimens, respectively. After 2 years of follow-up, the CR + PR rate was significantly higher in the change to GC + CNIs group after the switch compared to before the switch (80.00 vs. 31.43%, p < .001). It was also significantly higher in the change to GC + CYC group compared to before the switch (68.42 vs. 31.58%, p = .023). The recurrence rate was significantly higher in the maintain GC + CNIs and change to GC + CNIs groups than in the maintain GC + CYC and change to GC + CYC groups (25.14 vs 6.36%, p < .001). The disengagement rate from immunotherapy was significantly higher in the maintain GC + CYC group and the change to GC + CYC group than in the maintain GC + CNIs group and the change to GC + CNIs group (76.36% vs 29.71%, p < .001). High titer of anti-phospholipase A2 receptor (anti-PLA2R) antibody (95%CI: 0.199-0.947, p = .036) and serum C3 (95%CI: 0.030-0.570, p = .007) were independent risk factors, while serum IgG (95%CI: 1.000-1.331, p = .050) was a favorable factor for achieving CR. Anti-PLA2R antibody was the independent risk factor that affected the worse renal condition (p = .023). CONCLUSIONS: Timely change of treatment regimen can significantly enhance therapeutic effect. Compared with patients administered with CYC, those administered with CNIs were less likely to leave treatment and had a higher recurrence rate.
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Glomerulonefritis Membranosa , Humanos , Glomerulonefritis Membranosa/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Estudios Retrospectivos , Ciclofosfamida/uso terapéutico , Glucocorticoides/uso terapéutico , AutoanticuerposRESUMEN
N-fused pyrrolidinyl spirooxindole belongs to a class of privileged heterocyclic scaffolds and is prevalent in natural alkaloids and synthetic pharmaceutical molecules. To realize the switchable synthesis of divergent N-fused pyrrolidinyl spirooxindoles for further biological activity evaluation via a substrate-controlled strategy, a chemically sustainable, catalysis-free, and dipolarophile-controlled three-component 1,3-dipolar cycloaddition of isatin-derived azomethine ylides with diverse dipolarophiles is described in this work. A total of 40 functionalized N-fused pyrrolidinyl spirooxindoles were synthesized in 76-95% yields with excellent diastereoselectivities (up to >99:1 dr). The scaffolds of these products can be well-controlled by employing different 1,4-enedione derivatives as dipolarophiles in EtOH at room temperature. This study provides an efficient strategy to afford a spectrum of natural-like and potentially bioactive N-fused pyrrolidinyl spirooxindoles.
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Isatina , Reacción de Cicloadición , Isatina/químicaRESUMEN
In this study, we aimed to quantify the transport and fate of PAHs in different environmental phases (air, seawater, soil, sediment and fish), verify application of the Level III fugacity model in a bay simulation, and understand the transport and fate of PAHs in the bay environment on a macroscopic scale. The simulated average concentrations of ∑16PAH in the air and soil (23.8 ng/m3 and 1080.91 ng/g, respectively), which is as a background reference data for the Haizhou Bay. In addition, the soil (307 t), fish (29.4 t), and sediment (9.72 t) phases were found to be important reservoirs in the Haizhou Bay. Emissions from road vehicles (658 t) accounted for the largest share of PAH emissions in the area, and atmospheric deposition contributed most to the input of PAHs to the polluted area in the region. Whereas the contribution of river runoff input was small, and degradation loss was the main output pathway.
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Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Animales , Hidrocarburos Policíclicos Aromáticos/análisis , Bahías , Monitoreo del Ambiente , Agua de Mar , Suelo , China , Contaminantes Químicos del Agua/análisis , Sedimentos GeológicosRESUMEN
Novel monometallic (µ-LL')Ru, Ru(µ-LL'), homobimetallic Ru(µ-LL')Ru, and heterodimetallic Ru(µ-LL')Os and Os(µ-LL')Ru complexes based on two asymmetrical ligands LL' (where LL' = L1L1', L2L2') have been synthesized and characterized. Spectroscopic analysis indicates that all complexes exhibit intense spin-allowed ligand-centered (LC) transitions at 288 nm and Ru-based moderate spin-allowed MLCT absorption between 440-450 nm. The Ru(µ-LL')Os and Os(µ-LL')Ru dinuclear complexes show Os-based unit absorption in the range of 565-583 nm. The Ru-based units of the complexes present different emission intensities due to differing steric hindrance at the coordination sites of the two bridging ligands. The Os(µ-LL')Ru dinuclear complexes present weaker emission intensity than their parent monometallic complexes (µ-LL')Ru. These results indicate that the emission of Os(µ-LL')Ru dinuclear complexes is quenched by the Os(II)-based units.
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Rutenio , Estructura Molecular , Ligandos , Rutenio/química , Espectroscopía de Resonancia Magnética , Transferencia de EnergíaRESUMEN
Precise cell detecting and counting is meaningful in circulating tumor cells (CTCs) analysis. In this work, a simple cyclic olefin copolymer (COC) microflow cytometer device was developed for size-resolved CTCs counting. The proposed device is constructed by a counting channel and a pinched injection unit having three channels. Through injection flow rate control, microspheres/cells can be focused into the centerline of the counting channel. Polystyrene microspheres of 3, 9, 15, and 20 µm were used for the microspheres focusing characterization. After coupling to laser-induced fluorescence detection technique, the proposed device was used for polystyrene microspheres counting and sizing. A count accuracy up to 97.6% was obtained for microspheres. Moreover, the proposed microflow cytometer was applied to CTCs detecting and counting. To mimic blood sample containing CTCs and CTCs mixture with different subtypes, an MDA-MB-231 (human breast cell line) spiked red blood cells sample and a mixture of MDA-MB-231 and MCF-7 (human breast cell line) sample were prepared, respectively, and then analyzed by the developed pinched flow-based microfluidic cytometry. The simple fabricated and easy operating COC microflow cytometer exhibits the potential in the point-of-care clinical application.
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Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Humanos , Microfluídica/métodos , Células Neoplásicas Circulantes/patología , Poliestirenos , Citometría de Flujo , Eritrocitos/patología , Línea Celular Tumoral , Separación Celular/métodosRESUMEN
International students who pursue their academic goals in United States are prone to difficulties when attempting to build social resources and adjust to the new culture. Social media is a practical means of connection due to its ease of use and accessibility. Previous research has indicated contradictory effects of social media use on academic engagement. In addition to the direct effect, this research examined social media use influences on international students' learning engagement by mediating social capital and cultural adjustment. A total of 209 international students completed a web-based survey distributed via e-mail and social media between November 2021 and May 2022. Data were analyzed using Structural Equation Model. Results showed that only purposely using social media to collaborate with learning counterparts or materials directly improves international students' learning engagement. Other uses of social media (e.g., expanding new resources, solidifying close relationships) have no significant direct effects. Nonetheless, they are essential to improving levels of learning engagement via the mediation of bridging capital (social resources attributed to expanding relationships) and students' cultural adjustment in the U.S. International students' bonding capital (social resources available through trustworthy relationships) and home cultural retention showed little direct or indirect effects on learning engagement. This study recognizes the importance of social resources and cultural adjustment for international students. Also, this study provides valuable information to educators and administrators, as there is a need to identify the underlying mechanisms to contribute feasible learning intervention approaches and alleviate negative effects for international students.