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Watershed ecosystems play a pivotal role in maintaining the global carbon cycle and reducing global warming by serving as vital carbon reservoirs for sustainable ecosystem management. In this study, we based on the "quantity-mechanism-scenario" frameworks, integrate the MCE-CA-Markov and InVEST models to evaluate the spatiotemporal variations of carbon stocks in mid- to high-latitude alpine watersheds in China under historical and future climate scenarios. Additionally, the study employs the Geographic Detector model to explore the driving mechanisms influencing the carbon storage capacity of watershed ecosystems. The results showed that the carbon stock of the watershed increased by about 15.9 Tg from 1980 to 2020. Fractional Vegetation Cover (FVC), Digital Elevation Model (DEM), and Mean Annual Temperature (MAT) had the strongest explanatory power for carbon stocks. Under different climate scenarios, it was found that the SSP2-4.5 scenario had a significant rise in carbon stock from 2020 to 2050, roughly 24.1 Tg. This increase was primarily observed in the southeastern region of the watersheds, with forest and grassland effectively protected. Conversely, according to the SSP5-8.5 scenario, the carbon stock would decrease by about 50.53 Tg with the expansion of cultivated and construction land in the watershed's southwest part. Therefore, given the vulnerability of mid- to high-latitude mountain watersheds, global warming trends continue to pose a greater threat to carbon sequestration in watersheds. Our findings carry important implications for tackling potential ecological threats in mid- to high-latitude watersheds in the Northern Hemisphere and assisting policymakers in creating carbon sequestration plans, as well as for reducing climate change.
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Carbono , Cambio Climático , Ecosistema , Monitoreo del Ambiente , China , Carbono/análisis , Secuestro de Carbono , Ciclo del Carbono , Conservación de los Recursos Naturales , Modelos TeóricosRESUMEN
Proton exchange membrane water electrolysers promise to usher in a new era of clean energy, but they remain a formidable obstacle in designing active and durable electrocatalysts for the acidic oxygen evolution reaction (OER). In this study, a protonated iridium oxide embedded with single-atom dispersed ruthenium atoms (H3.8Ir1- xRuxO4) that demonstrates exceptional activity and stability in acidic water oxidation is introduced. The single Ru dopants favorably induce localized oxygen vacancies in the IrâO lattice, synergistically strengthening the adsorption of OOH* intermediates and enhancing the intrinsic OER activity. In addition, the preferential oxidation of Ru and the electronegativity of the oxygen vacancies significantly stabilize the IrâO active sites, improving the OER stability. Consequently, the H3.8Ir1â xRuxO4 catalyst shows an overpotential of 255 mV at 10 mA cm-2 and displays exceptional catalytic endurance in acidic electrolytes, surpassing 1100 h, representing a remarkable one-order-of-magnitude increase in stability compared to that of pristine H3.8IrO4. A proton exchange membrane electrolyser utilizing the H3.8Ir1- xRuxO4 catalyst as an anode exhibits stable performance for more than 1280 h under a high current density of 2 A cm-2.
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Premature ovarian insufficiency (POI) critically affects female reproductive health, with obesity being a significant and recognized risk factor. Interleukin-27 (IL-27), known for its role in immune modulation and inflammation, has garnered attention in metabolic syndrome research. Nonetheless, the role of these immunometabolic factors on the initiation of POI remains to be unraveled. Our investigation delves into the influence of impaired IL-27 signaling on POI induction, particularly under the challenge of a high-fat diet (HFD). We analyzed patients' serum profiles and established a correlation of increased serum triglycerides with decreased IL-27 levels in POI cases. Experiments on C57BL/6 mice lacking the IL-27 receptor alpha (Il27ra-/-) revealed that when subjected to HFD, these mice developed hallmark POI symptoms. This includes escalated lipid deposition in both liver and ovarian tissues, increased ovarian macrophages cellular aging, and diminished follicle count, all pointing to compromised ovarian function. These findings unveil a novel pathway wherein impaired IL-27 signaling potentiates the onset of POI in the presence of HFD. Understanding the intricate interplay between IL-27, metabolic alterations, and immune dysregulation sheds light on potential therapeutic avenues for managing POI, offering hope for improved reproductive health outcomes.
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BACKGROUND: Radioresistance and immune escape are crucial reasons for unsatisfactory therapeutic effects of glioblastoma (GBM). Although triggering receptor expressed on myeloid cells-2 (TREM2) involved in forming immunosuppressive microenvironment, but the underlying mechanism and its roles in mediating cancer radioresistance remain unclear, moreover, the efficient delivery of drugs targeting TREM2 to GBM encounters serious challenges. Hence, this study aimed to elucidate the effect and mechanisms of targeted TREM2 silencing on reversing the radioresistance and immune escape of GBM aided by a glutathione-responsive biomimetic nanoparticle (NP) platform. METHODS: Radioresistant GBM cell lines and TREM2 stable knockdown GBM cell lines were firstly established. RNA sequencing, colony formation assay, western blot, enzyme-linked immunosorbent assay and co-immunoprecipitation assay were used to detect the molecular mechanisms of TREM2 in regulating the radioresistance and immune escape of GBM. The glutathione-responsive biomimetic NP, angiopep-2 (A2)- cell membrane (CM)-NP/siTREM2/spam1, was then constructed to triply and targeted inhibit TREM2 for in vivo study. Orthotopic GBM-bearing mouse models were established to evaluate the anti-GBM effect of TREM2 inhibition, multiplex immunofluorescence assay was conducted to detect the infiltration of immune cells. RESULTS: TREM2 was a regulator in accelerating the radioresistance and immune escape of GBM through participating in DNA damage repair and forming a positive feedback loop with high mobility group box 1 (HMGB1) to cascade the activation of Toll-like receptor 4 (TLR4)/protein kinase B (Akt) signaling. A2-CM-NP/siTREM2/spam1 was successfully synthesized with excellent passive targeting, active targeting and homologous targeting, and the in vivo results exhibited its remarkable anti-GBM therapeutic effect through promoting the infiltration of type 1 helper T cells and CD8+T cells, reducing the infiltration of type 2 helper T cells and regulatory T cells, repolarizing macrophages to M1-type, and decreasing the secretion of pro-tumor and immunosuppressive cytokines. CONCLUSIONS: Targeting TREM2 therapy is a promising avenue for optimizing radiotherapy and immunotherapy to improve the prognosis of GBM patients.
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Glioblastoma , Proteína HMGB1 , Glicoproteínas de Membrana , Proteínas Proto-Oncogénicas c-akt , Tolerancia a Radiación , Receptores Inmunológicos , Transducción de Señal , Receptor Toll-Like 4 , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/inmunología , Glioblastoma/genética , Receptores Inmunológicos/metabolismo , Humanos , Animales , Línea Celular Tumoral , Glicoproteínas de Membrana/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor Toll-Like 4/metabolismo , Proteína HMGB1/metabolismo , Escape del Tumor , Ratones , Retroalimentación Fisiológica , Ratones Desnudos , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patologíaRESUMEN
This study aims to evaluate the pork meat quality after ultrasonic brining at different frequencies, thereby providing a more comprehensive understanding of the effects of ultrasound marination on meat. The texture profile analysis showed that ultrasonic curing at various frequencies significantly improved the textural properties of samples, especially at 26.8 kHz, resulting in a reduction of tenderness, hardness, and chewiness values by 44%, 43%, and 44%, respectively. The cooking loss of samples marinated by ultrasound decreased from 27% without ultrasonic treatment to 22%, indicating a significant improvement in water-holding capacity, while the changes in pH had only a subtle impact on pork quality. Meanwhile, the color of pork became more rosy hue due to decreased Lâ values and increased aâ values, which was mainly attributed to an elevated proportion of oxymyoglobin and reduced metmyoglobin content. Additionally, ultrasonic marination did not exert a negative impact on the oxidation of pork protein and lipids. After roasting, samples marinated by ultrasound exhibited a significantly higher abundance of volatile flavor compounds compared to static marinated meat (with an increase of 16 flavor substances) and fresh pork (with an increase of 24 flavor substances), demonstrating the efficacy of ultrasonic marination in enhancing the overall flavor and taste profile of pork. Consequently, the application of ultrasonic technology holds great potential for the "home kitchen type" rapid marination.
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OBJECTIVE: Combing PD-1/PD-L1 immune checkpoint inhibitors with natural products has exhibited better efficacy than monotherapy. Hence, the purpose of this research was to examine the anti-cancer effects of brusatol, a natural quassinoid-terpenoid derived from Brucea javanica, when used in conjunction with an anti-mouse-PD-1 antibody in a murine head and neck squamous cell carcinoma (HNSCC) model and elucidate underlying mechanisms. DESIGN: A murine HNSCC model and an SCC-15 cell xenograft nude mouse model were established to investigate the anti-cancer effects of brusatol and anti-PD-1 antibody. Mechanistic studies were performed using immunohistochemistry. Cell proliferation, migration, colony formation, and invasion were evaluated by MTT, migration, colony formation, and transwell invasion assays. PD-L1 levels in oral squamous cell carcinoma (OSCC) cells were assessed through qRT-PCR, flow cytometry, and western blotting assays. The impact of brusatol on Jurkat T cell function was assessed by an OSCC/Jurkat co-culture assay. RESULTS: Brusatol improved tumor suppression by anti-PD-1 antibody in HNSCC mouse models. Mechanistic studies revealed brusatol inhibited tumor cell growth and angiogenesis, induced apoptosis, increased T lymphocyte infiltration, and reduced PD-L1 expression in tumors. Furthermore, in vitro assays confirmed brusatol inhibited PD-L1 expression in OSCC cells and suppressed cell migration, colony formation, and invasion. Co-culture assays indicated that brusatol's PD-L1 inhibition enhanced Jurkat T cell-mediated OSCC cell death and reversed the inhibitory effect induced by OSCC cells. CONCLUSIONS: Brusatol improves anti-PD-1 antibody efficacy by targeting PD-L1, suggesting its potential as an adjuvant in anti-PD-1 immunotherapy.
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Antígeno B7-H1 , Proliferación Celular , Ratones Desnudos , Receptor de Muerte Celular Programada 1 , Cuassinas , Carcinoma de Células Escamosas de Cabeza y Cuello , Animales , Ratones , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Humanos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Cuassinas/farmacología , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Ensayos Antitumor por Modelo de Xenoinjerto , Células Jurkat , Citometría de Flujo , Apoptosis/efectos de los fármacos , Western Blotting , InmunohistoquímicaRESUMEN
In this study, a targeted nanocarrier was developed by functionalizing graphene oxide with polyethyleneimine and folic acid, intended for loading oridonin. The nanocarrier was successfully synthesized and characterized using an ultraviolet spectrum, Fourier transform infrared spectroscopy and scanning electron microscopy. The nanocarrier demonstrated a remarkable oridonin loading capacity, reaching 424.8 µg/mg, as determined by ultra-high performance liquid chromatography. In vitro drug release experiments exhibited a pH-dependent release profile, with a higher cumulative release in an acidic environment. The release mechanism followed the Ritger-Peppas equation model. Cytotoxicity assays indicated minimal toxicity of the nanocarrier. Enhanced cellular uptake by MCF7 cells was observed for carriers functionalized with folate and polyethyleneimine. These findings highlight the potential of functionalized graphene oxide as a promising carrier for oridonin delivery in biomedical applications.
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Neoplasias de la Mama , Diterpenos de Tipo Kaurano , Portadores de Fármacos , Grafito , Grafito/química , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/farmacología , Humanos , Células MCF-7 , Portadores de Fármacos/química , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Antineoplásicos/farmacología , Antineoplásicos/química , Liberación de Fármacos , Supervivencia Celular/efectos de los fármacos , Ácido Fólico/química , Nanopartículas/química , Cromatografía Líquida de Alta Presión/métodosRESUMEN
A fluorescence biosensor for determination of aflatoxin B1 (AFB1) based on polydiacetylene (PDA) liposomes and exonuclease III (EXO III)-assisted recycling amplification was developed. The AFB1 aptamer partially hybridizes with complementary DNA (cDNA), which is released upon recognition of AFB1 by the aptamer. Subsequently, the cDNA hybridizes with hairpin H to form double-stranded DNA that undergoes digestion by EXO III, resulting in the cyclic release of cDNA and generation of capture DNA for further reaction. The capture DNA then hybridizes with probe modified on PDA liposomes, leading to aggregation of liposomes and subsequent fluorescence production. This strategy exhibited a limit of detection of 0.18 ng/mL within the linear range 1-100 ng/mL with a determination coefficient > 0.99. The recovery ranged from 92.81 to 106.45%, with relative standard deviations (RSD) between 1.73 and 4.26%, for corn, brown rice, peanut butter, and wheat samples. The stability, accuracy, and specificity of the method demonstrated the applicability for real sample analysis.
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Aflatoxina B1 , Técnicas Biosensibles , Exodesoxirribonucleasas , Límite de Detección , Liposomas , Polímero Poliacetilénico , Polímero Poliacetilénico/química , Liposomas/química , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/metabolismo , Técnicas Biosensibles/métodos , Aflatoxina B1/análisis , Aptámeros de Nucleótidos/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Poliinos/química , Espectrometría de Fluorescencia/métodos , Zea mays/química , Triticum/química , Oryza/química , Polímeros/química , Contaminación de Alimentos/análisisRESUMEN
Improving the hydrophobic properties of aluminum alloys is crucial for industry. In previous reports, researchers prepared superhydrophobic surfaces by fabricating micro-nanostructures on the metal surface with a nanosecond laser. However, no researchers have formed microquadrangular groove structures on the metal surface. In this article, inspired by the bamboo leaf, a microquadrangular structure is designed and processed using nanosecond laser technology to form a superhydrophobic functional surface. The effects of laser processing parameters, such as laser power, scanning speed, scanning time, defocus and fill spacing on the size, surface morphology features, and wettability of the microquadrangular structure, are investigated by a single-factor experimental method. The experimental results show the optimal size of the processed microquadrangular structure obtained from the experiment with an error of 1.28% from the design size, where the fill spacing has the greatest effect on the size and the scanning time, defocus, and fill spacing have great influence on the surface morphology. The contact angle of water drops on the surface can reach 154.7°, and the power has the greatest influence on the wettability. Laser parameters have distinct effects on the properties of the materials. Therefore, by regulation of the laser parameters, the formation of the microstructure can be availably controlled and the result of hydrophobicity can be achieved.
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In this study, a sensitive dual-signal electrochemiluminescence (ECL) immunosensor was developed for okadaic acid (OA) detection utilizing copper nanoclusters (CuNCs) and Ru(bpy)32+-doped silica nanoparticles (RuSiNPs). Interestingly, the CuNCs could simultaneously enhance both cathodic (-0.95 V) and anodic (+1.15 V) ECL signals of RuSiNPs, forming a dual-signal ECL sensing platform. Further, RuSiNPs@CuNCs were used as immunomarkers by covalently conjugating them with an anti-OA monoclonal antibody (mAb) to form probes. Finally, dual ECL signals of the immunosensor were fabricated and showed good linear relationships with OA concentrations in the range of 0.05-70 ng mL-1, having a median inhibitory concentration (IC50) of 1.972 ng mL-1 and a limit of detection of 0.039 ng mL-1. Moreover, the constant ratio of the cathodic and anodic ECL peaks achieved self-calibration of the detection signal and improved the reliability of the results. Finally, we successfully applied the ECL sensor to detect OA in spiked oyster samples.
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Cobre , Técnicas Electroquímicas , Mediciones Luminiscentes , Ácido Ocadaico , Dióxido de Silicio , Cobre/química , Dióxido de Silicio/química , Mediciones Luminiscentes/métodos , Mediciones Luminiscentes/instrumentación , Ácido Ocadaico/análisis , Nanopartículas/química , Animales , Técnicas Biosensibles , Límite de Detección , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Nanopartículas del Metal/químicaRESUMEN
Chlorinated organic compounds (COCs) are typical refractory organic compounds, having high biological toxicity. These compounds are a type of pervasive pollutants that can be present in polluted soil, air, and various types of waterways, such as groundwater, rivers, and lakes, posing a significant threat to the ecological environment and human health. Bioelectrochemical systems (BESs) are an effective strategy for the degradation of bio-refractory compounds. BESs improve the waste treatment efficiency through the application of weak electrical stimulation. This review discusses the processes of BESs configurations and degradation performances in different environmental media including wastewater, soil, waste gas and groundwater. In addition, the degradation mechanisms and performance-enhancing additives are summarized. The future challenges and perspectives on the development of BES for COCs removal are briefly discussed.
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Biodegradación Ambiental , Técnicas Electroquímicas , Aguas Residuales/química , Hidrocarburos Clorados/metabolismo , Contaminantes Químicos del Agua/metabolismo , Agua Subterránea/química , Compuestos Orgánicos/metabolismoRESUMEN
Proper timing of vigilance states serves fundamental brain functions. Although disturbance of sleep onset rapid eye movement (SOREM) sleep is frequently reported after orexin deficiency, their causal relationship still remains elusive. Here, we further study a specific subgroup of orexin neurons with convergent projection to the REM sleep promoting sublaterodorsal tegmental nucleus (OXSLD neurons). Intriguingly, although OXSLD and other projection-labeled orexin neurons exhibit similar activity dynamics during REM sleep, only the activation level of OXSLD neurons exhibits a significant positive correlation with the post-inter-REM sleep interval duration, revealing an essential role for the orexin-sublaterodorsal tegmental nucleus (SLD) neural pathway in relieving REM sleep pressure. Monosynaptic tracing reveals that multiple inputs may help shape this REM sleep-related dynamics of OXSLD neurons. Genetic ablation further shows that the homeostatic architecture of sleep/wakefulness cycles, especially avoidance of SOREM sleep-like transition, is dependent on this activity. A positive correlation between the SOREM sleep occurrence probability and depression states of narcoleptic patients further demonstrates the possible significance of the orexin-SLD pathway on REM sleep homeostasis.
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To explore the potential mechanism in Cuscuta sinensis on diarrhea-type irritable bowel syndrome using network pharmacology and molecular docking techniques. First, the active components and related targets of Cuscuta were found setting oral utilization >30% and drug-like properties greater than or equal to 0.18 as filter information from TCMSP database. The targets of diarrheal irritable bowel syndrome were compiled by searching DrugBank, GeneCards, OMIM, PharmGkb, and TTD databases. The intersections of drugs and targets related to the disease were taken for gene ontology enrichment and Kyoto encyclopedia of genes and genomes enrichment analyses, to elucidate the potential molecular mechanisms and pathway information of Cuscuta sinensis for the treatment of diarrheal irritable bowel syndrome. The protein-protein interaction network was constructed by using the STRING database and visualized with Cytoscape_v3.10.0 software to find the protein-protein interaction network core At last, molecular docking was performed to validate the combination of active compounds with the core target. The target information of Cuscuta and diarrhea-type irritable bowel syndrome was compiled, which can be resulted in 11 active compounds such as quercetin, kaempferol, isorhamnetin, ß-sitosterol, and another 17 core targets such as TP53, IL6, AKT1, IL1B, TNF, EGFR, etc, whose Kyoto encyclopedia of genes and genomes was enriched in the pathways of lipids and atherosclerosis, chemical carcinogenesis-receptor activation, PI3K-Akt signaling pathway, and fluid shear stress and atherosclerosis, etc. Docking demonstrated that the core targets and the active compounds were able to be better combined. Cuscuta chinensis may exert preventive effects on diarrhea-type irritable bowel syndrome by reducing intestinal inflammation, protecting intestinal mucosa, and playing an important role in antioxidant response through multi-targets and multi-pathways.
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Cuscuta , Diarrea , Síndrome del Colon Irritable , Simulación del Acoplamiento Molecular , Farmacología en Red , Mapas de Interacción de Proteínas , Síndrome del Colon Irritable/tratamiento farmacológico , Humanos , Diarrea/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéuticoRESUMEN
BACKGROUND: The Chinese government has formulated a series of policies and strengthened training of general practitioners (GPs) to support their role as "gatekeepers" of residents' health. This study aimed to explore the core competencies of Chinese GPs and develop a competency framework in line with China's actual conditions, which can provide a more scientific basis for the education, training, and evaluation of GPs. METHODS: Literature analysis and behaviour event interviews were conducted to build the competency dictionary and the initial version of the competency model. Two rounds of Delphi were performed to gain consensus on the final model. The questionnaire survey was carried out in 10 provinces (municipalities, autonomous regions) of China, and GPs were invited to score the importance of each competency item. The total sample was randomly divided into two groups. One group was for exploratory factor analysis (EFA), and the other was for confirmatory factor analysis (CFA) to examine the scale's reliability and validity. RESULTS: The dictionary of general practitioners' competency including 107 competency items was constructed. After two rounds of Delphi, a consensus was reached on 60 competencies in 6 domains. A total of 1917 valid questionnaires were obtained in the nationwide survey. The average importance score of all second-level indicators is 4.53 ± 0.45. The Cronbach's α coefficient is 0.984. The results of the five factors extracted by EFA showing the 68.16% cumulative explained variance variation is considered to be consistent with the six dimensions obtained by Delphi after thorough discussion. The model fitness indexes obtained by CFA were acceptable (χ2/df = 4.909, CFI = 0.869, NFI = 0.841, RMSEA = 0.065). The values of the composite reliability (CR) of the six dimensions were all greater than 0.7 (0.943, 0.927, 0.937, 0.927, 0.943, 0.950), and the average of variance extracted (AVE) were all greater than 0.5 (0.562, 0.613, 0.649, 0.563, 0.626, 0.635). The results showed that the model has good reliability and validity. CONCLUSION: A competency model for GPs suited to China has been developed, which may offer guidance for future training and medical licensing examinations of GPs.
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Competencia Clínica , Técnica Delphi , Médicos Generales , Humanos , Competencia Clínica/normas , China , Encuestas y Cuestionarios , Masculino , Femenino , Reproducibilidad de los Resultados , Adulto , Persona de Mediana Edad , Análisis Factorial , ConsensoRESUMEN
The main disposal method for municipal solid waste (MSW), including the growing worldwide volumes of kitchen waste, involves transport to landfills. Because kitchen waste is mainly composed of organic matter and has a high moisture content, large amounts of leachate and landfill gas are generated when it is sent to landfills. Therefore, rapid waste stabilization is essential. In this study, four semi-aerobic bioreactors (named NS, SS, MS, and LS) were established with void fractions of 33.76%, 39.84%, 44.62%, and 41.31%, respectively. The results showed that the void fractions of landfill directly affected the gas flow path. When the landfill void fraction was small (e.g., NS), most airflow traveled directly through the pipeline and minimal airflow entered the waste layer. When the landfill void fraction was large (e.g., MS), air easily entered the waste layer and some air flowed into the gas vent with the landfill gas. As the reaction proceeded, the void fraction gradually decreased due to gravity-induced sedimentation. During the water addition experiment, the voids were occupied by water, leading to formation of an anaerobic area. Among the four bioreactors, only MS had negligible formation of an anaerobic zone in the center. Methane (CH4) generation was detected only at the connection between the gas vent and the leachate collection pipe. A larger void fraction led to formation of a smaller anaerobic zone. The ratio of air flowing in pipeline was lowest in MS. These results indicated that a large void fraction promotes the decomposition of organic matter.
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Reactores Biológicos , Eliminación de Residuos , Instalaciones de Eliminación de Residuos , Eliminación de Residuos/métodos , Aerobiosis , Residuos Sólidos/análisisRESUMEN
The II-I phase transition of isotactic poly(1-butene) (iPBu) leads to improved mechanical performance. However, this will take several weeks and increase storage and processing costs. In this work, shear forces are introduced into the supercooled iPBu melt, and the effects of isothermal crystallization temperature (Tc) and shear temperature (Tshear) on crystallization and phase transition are explored. Shear-induced transcrystalline morphology of Form II with a significantly shortened crystallization induction period can be observed at relatively high Tc (105 °C). Besides, the shear-induced Form II can transit to Form I faster than the unsheared one. In addition, the phase transition rate increases as the Tshear decreases, with the fastest rate occurring at Tshear of 120 °C. The half transition time (t1/2) is measured as 6.3 h when Tc = 105 °C, Tshear = 120 °C, which is much shorter than the 20.7 h required for unsheared samples. The accelerated phase transition of iPBu can be attributed to the stretching of molecular chains, resulting from shear treatment. This study provides a quantitative analysis of the influence of the shear treatment and the Tshear on the II-I phase transition rate. It also presents a cost-effective and straightforward approach for expediting the phase transition process.
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Transición de Fase , Polienos/química , Cristalización , Temperatura , Polímeros/química , Resistencia al CorteRESUMEN
The mitochondrial enzyme arginase-2 (Arg-2) is implicated in the pathophysiology of contrast-induced acute kidney injury (CI-AKI). Therefore, Arg-2 represents a candid target for CI-AKI prevention. Here, layer-by-layer (LbL) assembled renal-targeting polymeric nanoparticles are developed to efficiently deliver small interfering RNA (siRNA), knockdown Arg-2 expression in renal tubules, and prevention of CI-AKI is evaluated. First, near-infrared dye-loaded poly(lactic-co-glycolic acid) (PLGA) anionic cores are electrostatically coated with cationic chitosan (CS) to facilitate the adsorption and stabilization of Arg-2 siRNA. Next, nanoparticles are coated with anionic hyaluronan (HA) to provide protection against siRNA leakage and shielding against early clearance. Sequential electrostatic layering of CS and HA improves loading capacity of Arg-2 siRNA and yields LbL-assembled nanoparticles. Renal targeting and accumulation is enhanced by modifying the outermost layer of HA with a kidney targeting peptide (HA-KTP). The resultant kidney-targeting and siRNA loaded nanoparticles (PLGA/CS/HA-KTP siRNA) exhibit proprietary accumulation in kidneys and proximal tubular cells at 24 h post-tail vein injection. In iohexol-induced in vitro and in vivo CI-AKI models, PLGA/CS/HA-KTP siRNA delivery alleviates oxidative and nitrification stress, and rescues mitochondrial dysfunction while reducing apoptosis, thereby demonstrating a robust and satisfactory therapeutic effect. Thus, PLGA/CS/HA-KTP siRNA nanoparticles offer a promising candidate therapy to protect against CI-AKI.
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Lesión Renal Aguda , Arginasa , Medios de Contraste , Nanopartículas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , ARN Interferente Pequeño , Nanopartículas/química , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/metabolismo , Animales , ARN Interferente Pequeño/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Medios de Contraste/química , Ratones , Arginasa/metabolismo , Arginasa/genética , Quitosano/química , Técnicas de Silenciamiento del Gen , Riñón/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Ácido Hialurónico/química , Masculino , Humanos , Ácido Láctico/química , Ácido Poliglicólico/química , Nanopartículas Capa por CapaRESUMEN
The addition of corn starch (CS) enhances the interfacial adhesion of the film-forming liquids (FFLs), weakening the internal relative molecular motion. As a result, the rheological properties and zeta potential values of the FFLs were affected. A tight spatial network structure between capsicum leaf protein (CLP), lignocellulose nanocrystals (LNCs) and CS can be formed through intermolecular entanglement and hydrogen bonding interactions. The crystallinity, thermal degradation temperature, tensile strength and water contact angle of the protein-based bionanocomposite films (PBBFs) increased with increasing CS addition. This is due to the transformation of the secondary space structure of the CLP inside the PBBFs and the increase in cohesion. However, the excessive addition of CS forms aggregated clusters on the surface of PBBFs, which increases the surface roughness of PBBFs and causes more light scattering. Therefore, the brightness and yellowness values of the PBBFs increase, and the transmittance decreases.
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Capsicum , Embalaje de Alimentos , Nanocompuestos , Hojas de la Planta , Proteínas de Plantas , Almidón , Zea mays , Nanocompuestos/química , Capsicum/química , Almidón/química , Hojas de la Planta/química , Embalaje de Alimentos/instrumentación , Proteínas de Plantas/química , Zea mays/química , Resistencia a la TracciónRESUMEN
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Ordinal response is commonly found in medicine, biology, and other fields. In many situations, the predictors for this ordinal response are compositional, which means that the sum of predictors for each sample is fixed. Examples of compositional data include the relative abundance of species in microbiome data and the relative frequency of nutrition concentrations. Moreover, the predictors that are strongly correlated tend to have similar influence on the response outcome. Conventional cumulative logistic regression models for ordinal responses ignore the fixed-sum constraint on predictors and their associated interrelationships, and thus are not appropriate for analyzing compositional predictors.To solve this problem, we proposed Bayesian Compositional Models for Ordinal Response to analyze the relationship between compositional data and an ordinal response with a structured regularized horseshoe prior for the compositional coefficients and a soft sum-to-zero restriction on coefficients through the prior distribution. The method was implemented with R package rstan using efficient Hamiltonian Monte Carlo algorithm. We performed simulations to compare the proposed approach and existing methods for ordinal responses. Results revealed that our proposed method outperformed the existing methods in terms of parameter estimation and prediction. We also applied the proposed method to a microbiome study HMP2Data, to find microorganisms linked to ordinal inflammatory bowel disease levels. To make this work reproducible, the code and data used in this paper are available at https://github.com/Li-Zhang28/BCO.