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Unregulated regional integrated development disrupts the reactive nitrogen (Nr) cycle, adding complexity to anthropogenic Nr environmental losses. The objective of this study was to establish a framework for mitigating anthropogenic Nr loss through a new regional integration perspective by analyzing anthropogenic Nr loss and integrated control strategies in the Yangtze River Delta (YRD) region from 2011 to 2020. The results revealed that the total Nr loss in the YRD ranged from 1780.7 to 1972.0 Gg N yr-1. Re-linking cropland and livestock is crucial for reducing Nr loss, as they act as the main sources of Nr loss. Spatial analysis at the regional scale revealed that regional integration has led to a dispersion of Nr loss, while uneven development among cities has resulted in a westward shift of 8.6 km in the Nr loss centroid, suggesting the need for the implementation of collaborative governance and integrated environmental regulation in the YRD. At the city scale, 27 cities were clustered into six types based on the similarity of Nr loss structural characteristics, allowing for the development of targeted reduction policies based on the specific Nr structural characteristics of each city. The results of driver and mitigation potential analysis indicated the feasibility of achieving the shared goal of sustainable regional integration and the application of optimal mitigation strategies in different cities and the YRD. Overall, the new-perspective framework established in this study provides valuable references for sustainable Nr management in the context of regional integration.
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Nanofiltration (NF) membranes, extensively used in advanced wastewater treatment, have broad application prospects for the removal of emerging trace organic micropollutants (MPs). The treatment performance is affected by several factors, such as the properties of NF membranes, characteristics of target MPs, and operating conditions of the NF system concerning MP rejection. However, quantitative studies on different contributors in this context are limited. To fill the knowledge gap, this study aims to assess critical impact factors controlling MP rejection and develop a feasible model for MP removal prediction. The mini-review firstly summarized membrane pore size, membrane zeta potential, and the normalized molecular size (λ = rs/rp), showeing better individual relationships with MP rejection by NF membranes. The Lindeman-Merenda-Gold model was used to quantitatively assess the relative importance of all summarized impact factors. The results showed that membrane pore size and operating pressure were the high impact factors with the highest relative contribution rates to MP rejection of 32.11% and 25.57%, respectively. Moderate impact factors included membrane zeta potential, solution pH, and molecular radius with relative contribution rates of 10.15%, 8.17%, and 7.83%, respectively. The remaining low impact factors, including MP charge, molecular weight, logKow, pKa and crossflow rate, comprised all the remaining contribution rates of 16.19% through the model calculation. Furthermore, based on the results and data availabilities from references, the machine learning-based random forest regression model was trained with a relatively low root mean squared error and mean absolute error of 12.22% and 6.92%, respectively. The developed model was then successfully applied to predict MPs' rejections by NF membranes. These findings provide valuable insights that can be applied in the future to optimize NF membrane designs, operation, and prediction in terms of removing micropollutants.
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Contaminantes Químicos del Agua , Purificación del Agua , Contaminantes Químicos del Agua/química , Purificación del Agua/métodosRESUMEN
Photosynthesis is a key process linking carbon and water cycles, and satellite-retrieved solar-induced chlorophyll fluorescence (SIF) can be a valuable proxy for photosynthesis. The TROPOspheric Monitoring Instrument (TROPOMI) on the Copernicus Sentinel-5P mission enables significant improvements in providing high spatial and temporal resolution SIF observations, but the short temporal coverage of the data records has limited its applications in long-term studies. This study uses machine learning to reconstruct TROPOMI SIF (RTSIF) over the 2001-2020 period in clear-sky conditions with high spatio-temporal resolutions (0.05° 8-day). Our machine learning model achieves high accuracies on the training and testing datasets (R2 = 0.907, regression slope = 1.001). The RTSIF dataset is validated against TROPOMI SIF and tower-based SIF, and compared with other satellite-derived SIF (GOME-2 SIF and OCO-2 SIF). Comparing RTSIF with Gross Primary Production (GPP) illustrates the potential of RTSIF for estimating gross carbon fluxes. We anticipate that this new dataset will be valuable in assessing long-term terrestrial photosynthesis and constraining the global carbon budget and associated water fluxes.
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BACKGROUND: Suid herpesvirus type 1 (SHV1) is a type of neurotropic virus able to infect various species. However, the clinical cases of human SHV1 encephalitis are still rarely reported, and the clinical characteristics, treatment, and prognosis of human SHV1 encephalitis are still unclear. METHODS: In this study, we reported 2 cases of human encephalitis associated with SHV1 infection and reviewed the other 18 cases from the literatures. A total of 20 cases with human SHV1 encephalitis were summarized and re-analyzed. RESULTS: Nineteen of 20 patients had a history of swine-related occupational exposure before illness onset. All patients initially presented with influenza-like symptoms and then developed seizures, disturbed consciousness, and endophthalmitis. All patients with clinical outcome of modified Rankin Scale of 5 or 6 suffered from rapid progressive respiratory failure. The results of cerebrospinal fluid (CSF) indicated aseptic or viral infection. MRI findings of SHV1 encephalitis were prone to distribute in temporal-frontal and insular cortex, which was similar to the pattern of herpes simplex virus encephalitis, while some cases with involvements of gray matter nuclei had a high rate of mortality. Metagenomic next-generation sequencing (mNGS) revealed that all patients had unique SHV1 sequences with variable reads in the CSF. CONCLUSIONS: The variant SHV1 can cause a new type of human viral encephalitis, characterized by acute, fulminating, and catastrophic central nervous system infection. Rapid progressive respiratory failure and extensive lesions of deep gray matter nuclei might be indicators to poor prognosis. No approved treatments for the encephalitis are available, but it is possible to diagnose encephalitis quickly by mNGS.
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Encefalitis por Herpes Simple , Encefalitis Viral , Herpesvirus Humano 1 , Herpesvirus Suido 1 , Animales , Encefalitis por Herpes Simple/diagnóstico , Encefalitis Viral/diagnóstico , Herpesvirus Humano 3 , Humanos , Imagen por Resonancia Magnética , PorcinosRESUMEN
In this work, with the purpose of developing an effective and inexpensive method, excitation-emission matrix fluorescence data and second-order calibration method based on the self-weighted alternating trilinear decomposition (SWATLD) algorithm were combined for simultaneous determination of 2-naphthoxyacetic acid (NOA) and 1-naphthaleneacetic acid methyl ester (NAAME) in environmental samples, i.e. soil and sewage samples. In order to investigate the prediction quality of the proposed method, different strategies, such as taking spectroscopic measurements in the presence of different matrix interferents and at different fluorescence spectrophotometers, were introduced to build calibration models and comparisons among them were done subsequently. The root-mean-square error of prediction and t-test were used to compare different SWATLD-based calibration models. The limits of detection obtained for NOA and NAAME were 0.36-0.95 ng mL(-1) and 1.32-2.69 ng mL(-1), respectively, for different models. Such a chemometrics-based protocol may possess great potential to be extended as a promising alternative for more practical applications in environment monitoring and for the design of small intelligent and field-portable analytical instruments that rely on statistical discrimination, not complete instrumental separation, of the target analytes even in the presence of unknown and uncalibrated interferences.
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Monitoreo del Ambiente , Modelos Estadísticos , Procesos Fotoquímicos , Reguladores del Crecimiento de las Plantas/análisis , Espectrometría de Fluorescencia , Algoritmos , Calibración , Límite de Detección , Control de Calidad , Aguas del Alcantarillado/análisis , Contaminantes del Suelo/análisisRESUMEN
In the present study, we developed a convenient, rapid, and sensitive immunochromatographic (IC) test strip to detect abrin in assay buffer and spiked abrin in test food samples. The abrin IC test strip was based on a sandwich format consisting of a monoclonal antibody and a polyclonal antibody. The anti-abrin A chain monoclonal antibody from mice was immobilized on a porous nitrocellulose membrane as a capture antibody, while the anti-abrin polyclonal antibody from rabbits was conjugated to colloidal gold particles, serving as a detection antibody. Both visual observation and quantitative analysis indicated that the lower detection of the strip was about 3 ng/ml when abrin was directly spiked into milk, orange juice, and drinking water at a concentration of 3 to 60 ng/ml; the analytical recovery rate was 92.2 to 128%. With this method, abrin spiked into food could be detected in less than 10 min. Moreover, the IC test strip showed no cross-reaction with the closely related phytotoxin ricin. Therefore, our test strip is an ideal candidate for the development of a kit for rapid and quantitative detection of abrin in food samples.
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Abrina/análisis , Cromatografía de Afinidad/métodos , Contaminación de Alimentos/análisis , Abrina/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Oro Coloide/química , Humanos , Ratones , Conejos , Juego de Reactivos para Diagnóstico , Tiras Reactivas , Sensibilidad y EspecificidadRESUMEN
The effectiveness of traditional Chinese medicine (TCM) against various diseases urges more low cost, speed and sensitive analytical methods for investigating the phamacology of TCM and providing a theoretical basis for clinical use. The potential of second-order calibration method was validated for the quantification of two effective ingredients of Schisandra chinensis in human plasma using spectrofluorimetry. The results obtained in the present study demonstrate the advantages of this strategy for multi-target determination in complex matrices. Although the spectra of the analytes are similar and a large number of interferences also exist, second-order calibration method could predict the accurate concentrations together with reasonable resolution of spectral profiles for analytes of interest owing to its 'second-order advantage'. Moreover, the method presented in this work allows one to simply experimental procedure as well as reduces the use of harmful chemical solvents.
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A rapid non-separative spectrofluorometric method based on the second-order calibration of excitation-emission matrix (EEM) fluorescence was proposed for the determination of napropamide (NAP) in soil, river sediment, and wastewater as well as river water samples. With 0.10 mol L(-1) sodium citrate-hydrochloric acid (HCl) buffer solution of pH 2.2, the system of NAP has a large increase in fluorescence intensity. To handle the intrinsic fluorescence interferences of environmental samples, the alternating penalty trilinear decomposition (APTLD) algorithm as an efficient second-order calibration method was employed. Satisfactory results have been achieved for NAP in complex environmental samples. The limit of detection obtained for NAP in soil, river sediment, wastewater and river water samples were 0.80, 0.24, 0.12, 0.071 ng mL(-1), respectively. Furthermore, in order to fully investigate the performance of second-order calibration method, we test the second-order calibration method using different calibration approaches including the single matrix model, the intra-day various matrices model and the global model based on the APTLD algorithm with nature environmental datasets. The results showed the second-order calibration methods also enable one or more analyte(s) of interest to be determined simultaneously in the samples with various types of matrices. The maintenance of second-order advantage has been demonstrated in simultaneous determinations of the analyte of interests in the environmental samples of various matrices.
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Contaminantes Ambientales/análisis , Naftalenos/análisis , Espectrometría de Fluorescencia/métodos , Calibración , Monitoreo del Ambiente/métodos , Fluorescencia , Herbicidas/análisis , Límite de Detección , Ríos , Contaminantes del Suelo/análisis , Espectrometría de Fluorescencia/normas , Contaminantes Químicos del Agua/análisisRESUMEN
A good immunogen was developed as an effective recombinant vaccine candidate that protected mice against botulinum neurotoxin serotype B (BoNT/B) intoxication. The Hc fragment of Clostridium botulinum neurotoxin type B (rBoNT/B-Hc) was cloned into the bacterial expression vector pQE-30, and the resulting vector was successfully expressed in the Escherichia coli M15 strain. The purified rBoNT/B-Hc protein was used to vaccinate mice and evaluate their survival against challenge with native BoNT/B. The mice that received three subcutaneous injections of rBoNT/B-Hc immunogen doses ranging from 0.25 to 6.25 µg mixed with Freund's adjuvant were completely protected against an intraperitoneal (i.p.) administration of 10,000 50% lethal doses (LD50) of BoNT/B. A dose response was observed in both the ELISA antibody titers and protective efficacy with increasing dose of immunogen. The work presented here demonstrates that the purified rBoNT/B-Hc was a highly effective immunogen and able to protect against a high-dose neurotoxin challenge.