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Regions can meet their development demands through trade, with the attendant environmental costs being shifted to other regions, and carbon emissions emitted from different industries could be transferred over long distances through the increasingly diversified trade network. However, it remains unclear how regional trade leads to the tele-connection and transfer of embodied carbon emissions form industries, and what is the structure and characteristics of the transfer. Thus, multiregional inputâoutput models and complex network analysis are employed to reveal the tele-connection of carbon emissions from industries in China. The results show that embodied carbon emissions from trade increased by 869.47 million tons during in five years, with North China being the largest outflow area, while the coastal regions being the inflow areas. Moreover, the secondary industry is the highest source of embodied carbon emissions, accounting for 96.68 % of the volume, and the transfer of carbon emissions mainly occurs in North and East China. In carbon emissions networks, North China holds a controlling position, as analysed by degree and strength. The first 23.3%-30% of nodes carry about 62.6%-72.4% of the entire carbon emissions flow, and the network conforms to scale-free features. Centrality further reveals that northern and coastal areas occupy core positions, with interregional carbon flows dominating the critical pathways in the network. The number of clusters evolved from three to four communities during 2012-2017 in the network, demonstrating that the carbon flow network is developing towards multipolarity and modularity. This study underscores the urgency of mitigating carbon emissions in industrial trade by identifying key nodes and cluster structures in emission networks.
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Carbono , Industrias , China , Comercio , Monitoreo del AmbienteRESUMEN
Electrocatalytic hydrogen atom-hydroxyl radical (H*-·OH) redox system is a promising approach for contaminant removal and mineralization. However, its working mechanism, especially the effect of H*, remains unclear, hindering its practical application. Herein, we constructed an electrochemical reactor equipped with our self-made Pd-loaded Ti/TiO2 nanotube cathode and a commercial boron-doped diamond anode. After fulfilling the electrode characterization and free radical detection, we employed coumarin and 7-azido-4-methylcoumarin as probes to confirm the participation of H* in the transformation of organic compounds. A comprehensive study on the degradation kinetics, reaction, and mineralization mechanisms using benzoic acid (BA) and 4-chlorophenol (4-CP) as model compounds was further conducted. The rate constants and total organic carbon removal of BA and 4-CP in the redox system increased compared with those of the individual oxidation and reduction processes. Theoretical calculations demonstrate that H* opens up alternative pathways for BA and 4-CP ring cleavage, forming quinones as reactive intermediates. Furthermore, H* facilitates the mineralization of the typical intermediates, maleic acid and fumaric acid, through C=C bond addition and H-abstraction from the 1,1-diol structure. The presence of H* provides alternative pathways for pollutant transformation, consequently reducing the treatment duration.
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Hidrógeno , Oxidación-Reducción , Hidrógeno/química , CinéticaRESUMEN
Industrial hypersaline wastewaters contain diverse pollutants that harm the environment. Recovering clean water, alkali and acid from these wastewaters can promote circular economy and environmental protection. However, current electrochemical and advanced oxidation processes, which rely on hydroxyl radicals to degrade organic compounds, are inefficient and energy intensive. Here we report a flow-through redox-neutral electrochemical reactor (FRER) that effectively removes organic contaminants from hypersaline wastewaters via the chlorination-dehalogenation-hydroxylation route involving radical-radical cross-coupling. Bench-scale experiments demonstrate that the FRER achieves over 75% removal of total organic carbon across various compounds, and it maintains decontamination performance for over 360 h and continuously treats real hypersaline wastewaters for two months without corrosion. Integrating the FRER with electrodialysis reduces operating costs by 63.3% and CO2 emissions by 82.6% when compared with traditional multi-effect evaporation-crystallization techniques, placing our system at technology readiness levels of 7-8. The desalinated water, high-purity NaOH (>95%) and acid produced offset industrial production activities and thus support global sustainable development objectives.
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Bacteria are pivotal to drinking water treatment and public health. However, the mechanisms of bacterial assembly and their impact on species coexistence remain largely unexplored. This study explored the assembly and succession of bacterial communities in two full-scale drinking water systems over one year. We observed a decline in bacterial biomass, diversity, and co-occurrence network complexity along the treatment processes, except for the biological activated carbon filtration stage. The conventional plant showed higher bacterial diversity than the advanced plant, despite similar bacterial concentrations and better removal efficiency. The biological activated carbon filter exhibited high phylogenetic diversity, indicating enhanced bacterial metabolic functionality for organic matter removal. Chlorination inactivated most bacteria but favored some chlorination-resistant and potentially pathogenic species, such as Burkholderia, Bosea, Brevundimonas, and Acinetobacter. Moreover, the spatiotemporal dynamics of the bacterial continuum were primarily driven by stochastic processes, explaining more than 78% of the relative importance. The advanced plant's bacterial community was less influenced by dispersal limitation and more by homogeneous selection. The stochastic process regulated bacterial diversity and influenced the complexity of the species co-occurrence network. These findings deepen our understanding of microbial ecological mechanisms and species interactions, offering insights for enhancing hygienic safety in drinking water systems.
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Bacterias , Agua Potable , Microbiología del Agua , Purificación del Agua , Agua Potable/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Purificación del Agua/métodos , Halogenación , Filtración , Biodiversidad , Abastecimiento de AguaRESUMEN
The occurrence and removal of 38 antibiotics from nine classes in two drinking water treatment plants (WTPs) were monitored monthly over one year to evaluate the efficiency of typical treatment processes, track the source of antibiotics in tap water and assess their potential risks to ecosystem and human health. In both source waters, 18 antibiotics were detected at least once, with average total antibiotic concentrations of 538.5 ng/L in WTP1 and 569.3 ng/L in WTP2. The coagulation/flocculation and sedimentation, sand filtration and granular activated carbon processes demonstrated limited removal efficiencies. Chlorination, on the other hand, effectively eliminated antibiotics by 48.7 ± 11.9%. Interestingly, negative removal was observed along the distribution system, resulting in a significant antibiotic presence in tap water, with average concentrations of 131.5 ng/L in WTP1 and 362.8 ng/L in WTP2. Source tracking analysis indicates that most antibiotics in tap water may originate from distribution system. The presence of antibiotics in raw water and tap water posed risks to the aquatic ecosystem. Untreated or partially treated raw water could pose a medium risk to infants under six months. Water parameters, for example, temperature, total nitrogen and total organic carbon, can serve as indicators to estimate antibiotic occurrence and associated risks. Furthermore, machine learning models were developed that successfully predicted risk levels using water quality parameters. Our study provides valuable insights into the occurrence, removal and risk of antibiotics in urban WTPs, contributing to the broader understanding of antibiotic pollution in water treatment systems.
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Antibacterianos , Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Agua Potable/química , Purificación del Agua/métodos , Antibacterianos/análisis , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , HumanosRESUMEN
BACKGROUND: The effect of radiotherapy waiting time after last induction chemotherapy (IC-RT) on prognosis of patients with locally advanced nasopharyngeal carcinoma (LANPC) needs further discussion. METHODS: Three hundred and six patients with LANPC diagnosed pathologically by induction chemotherapy (IC) and radiotherapy (RT) from 2013 to 2018 were selected for this study. RESULTS: The IC-RT was a risk factor for the post-treatment progression of LANPC (OR = 1.017 95%CI: 1.003-1.031), For patients with LANPC, the IC-RT > 40 days significantly reduced 5-year PFS (70% vs. 55%; p = 0.0012), 5-year OS (84% vs. 73%; p = 0.028), 5-year DMFS (80% vs. 66%; p = 0.003), 5-year LRFS (77% vs. 67%; p = 0.012). Indicating that patients with stage IVa who IC-RT > 40 days were found to be a significant predictor of aggravated PFS (HR = 2.69; 95%CI: 1.57-4.6), OS (HR = 2.55; 95%CI: 1.29-5.03), DMFS (HR = 3.07; 95%CI: 1.64-5.76) and LRFS (HR = 2.26; 95%CI: 1.21-4.21). CONCLUSION: The prognosis of patients will be adversely affected if the IC-RT exceeds 40 days, especially for stage IVa patients.
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Carcinoma , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Quimioterapia de Inducción , Listas de Espera , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/patología , Quimioradioterapia/efectos adversos , Carcinoma/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéuticoRESUMEN
In this paper, a wideband transmission unit cell is proposed for programmable metasurfaces operating in the Ka-band. The unit cell features a compact period of only 2.91 mm, corresponding to 0.34 λ0 at the center frequency of 35 GHz. A receiving layer, consisting of a patch loaded with two PIN diodes, is utilized to achieve 1-bit phase modulation, while a U-shaped patch serves as the transmitting layer to enable selection of linear polarization hold or conversion. Based on the multi-resonance principle, the proposed unit cell exhibits broadband behavior, as demonstrated by simulation results under periodic boundary conditions, which indicate a 3 dB transmission bandwidth of 29.4-40 GHz (30.5%). Two unit cells were fabricated and tested in a standard waveguide, with the minimum insertion loss of the two states tested being 1.2 dB and 3 dB bandwidths of 30.1-31.2 GHz and 33.5-38.5 GHz, respectively. The maximum 180° phase error is 10°, indicating the high quality of the proposed unit cell.
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Rhizosphere microbial colonization of the tea plant provides many beneficial functions for the host, But the factors that influence the composition of these rhizosphere microbes and their functions are still unknown. In order to explore the interaction between tea plants and rhizosphere microorganisms, we summarized the current studies. First, the review integrated the known rhizosphere microbial communities of tea tree, including bacteria, fungi, and arbuscular mycorrhizal fungi. Then, various factors affecting tea rhizosphere microorganisms were studied, including: endogenous factors, environmental factors, and agronomic practices. Finally, the functions of rhizosphere microorganisms were analyzed, including (a) promoting the growth and quality of tea trees, (b) alleviating biotic and abiotic stresses, and (c) improving soil fertility. Finally, we highlight the gaps in knowledge of tea rhizosphere microorganisms and the future direction of development. In summary, understanding rhizosphere microbial interactions with tea plants is key to promoting the growth, development, and sustainable productivity of tea plants.
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Camellia sinensis , Microbiota , Micorrizas , Rizosfera , Suelo , Árboles , Té , Microbiología del Suelo , Raíces de Plantas/microbiologíaRESUMEN
Density functional theory (DFT) is a powerful quantum mechanical computational tool to perform electronic structure calculations for materials. Few DFT methods can ensure accuracy and efficiency simultaneously. DFT + U + V is an alternative effective approach to overcome this drawback. However, the accuracy sensitively depends on the self-consistent estimation of the high-dimensional onsite and intersite Hubbard interaction U and V terms. We propose Bayesian optimization using a dropout (BOD) algorithm, one type of active learning method, to optimize U and V terms. The DFT + U + V with U/V obtained by BOD can produce improved electronic properties for diverse bulk materials of comparable quality to the hybrid functionals with lower computational cost compared to the linear response approach. Note that the band gaps calculated by BOD are somewhat different from that of hybrid functionals by simply applying the same U/V parameters as in the case of surface slabs and interfaces, which suggests that the transferability of U/V from the bulk models to slabs and interfaces is not as well as expected. BOD is extended to calculate the U/V parameters for slabs and interfaces and reach similar results as bulk solids. Moreover, we find that the U/V are reasonably transferable between surface slabs and interfaces with different thicknesses under various effects of quantum confinement, which contributes to fast access to the electronic properties of large-scale systems with higher accuracy.
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Glycyrrhizin (GL) is one of the antagonists of highly conserved nuclear protein (HMGB1). The researches have shown that the glycosyl of GL is an important pharmacophore for GL binding to HMGB1, and it is the determinant factor for mechanism of action. To get the HMGB1 inhibitors with higher activity and good pharmacokinetic properties, two classes of GL analogues containing C-N glycoside bond were synthesized, and their anti-inflammatory, anti-oxidative stress and anti-septic kidney injury were evaluated. The results are as follows. First, in the anti-inflammatory assay, all the compounds inhibited NO release in some degree; among them, compound 6 displayed the strongest NO inhibitory effect with IC50 value of 15.9 µM, and compound 15 with IC50 of 20.2 µM. The two compounds not only decreased IL-1ß and TNF-α levels in RAW264.7 cells and HK-2 cells, but also downregulated the levels of NLRP3, P-NF-κB p65 and HMGB1 in activated HK-2 cells in a dose-dependent manner. Second, in the renal protection assay with H2O2-stimulated HK-2 cell line, they reduced MDA level and increased SOD in HK-2 cells; additionally, they also inhibited the HK-2 cell apoptosis and downregulated the Caspase-1 p20 level. Third, in the in vivo activity tests of the septic mouse, they also showed good activities just like in vitro, decreasing the IL-1ß, TNF-α, MDA, blood creatinine (Scr) and urea nitrogen (BUN) in serum, and increasing SOD levels in a dose-dependent manner. The immunoblotting results showed the two compounds downregulated the levels of HMGB1, P-NF-κB p65, NLRP3 and Caspase-1 p20 protein. All in all, the two compounds improved the renal injury of septic mice, and alleviated the tube wall structure damage and renal tubular dilation in kidney, which further proved by H&E staining. This suggests the two compounds have septic acute kidney injury activity, and they will be potential therapeutic drugs for septic acute kidney injury.
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Lesión Renal Aguda , Proteína HMGB1 , Sepsis , Ratones , Animales , Ácido Glicirrínico/farmacología , Ácido Glicirrínico/uso terapéutico , FN-kappa B/metabolismo , Proteína HMGB1/metabolismo , Proteína HMGB1/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR , Peróxido de Hidrógeno , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Sepsis/tratamiento farmacológico , Sepsis/metabolismo , Caspasas , Superóxido DismutasaRESUMEN
PURPOSE: Recurrence of breast cancer leads to a high lifetime risk and a low 5 year survival rate. Researchers have used machine learning to predict the risk of recurrence in patients with breast cancer, but the predictive performance of machine learning remains controversial. Hence, this study aimed to explore the accuracy of machine learning in predicting breast cancer recurrence risk and aggregate predictive variables to provide guidance for the development of subsequent risk scoring systems. METHODS: We searched Pubmed, EMBASE, Cochrane, and Web of Science. The risk of bias in the included studies was evaluated using prediction model risk of bias assessment tool (PROBAST). Meta-regression was adopted to explore whether there was a significant difference in the recurrence time by machine learning. RESULTS: Thirty-four studies involving 67,560 subjects were included, among whom 8695 experienced breast cancer recurrence. The c-index of prediction models was 0.814 (95%CI 0.802-0.826) and 0.770 (95%CI 0.737-0.803) in the training and validation sets, respectively; the sensitivity and specificity were 0.69 (95% CI 0.64-0.74), 0.89 (95% CI 0.86-0.92) in the training, and 0.64 (95% CI 0.58-0.70), 0.88 (95% CI 0.82-0.92) in the validation, respectively. Age, histological grading, and lymph node status are the most commonly used variables in model construction. Attention should be paid to unhealthy lifestyles such as drinking, smoking and BMI as modeling variables. Risk prediction models based on machine learning have long-term monitoring value for breast cancer population, and subsequent studies should consider using large-sample and multi-center data to establish risk equations for verification. CONCLUSION: Machine learning may be used as a predictive tool for breast cancer recurrence. Currently, there is a lack of effective and universally applicable machine learning models in clinical practice. We expect to incorporate multi-center studies in the future and attempt to develop tools for predicting breast cancer recurrence risk, so as to effectively identify populations at high risk of recurrence and develop personalized follow-up strategies and prognostic interventions to reduce the risk of recurrence.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Mama/patología , Pronóstico , Sensibilidad y Especificidad , Aprendizaje AutomáticoRESUMEN
We report here the clinical diagnosis and treatment and genetic mutations of an infant with You-Hoover-Fong syndrome (YHFS). The relevant literature review was conducted. A female infant aged 17 months was admitted to Nanhai Affiliated Maternity and Children's Hospital of Guangzhou University of Chinese Medicine due to "global development delay complicated with postnatal growth retardation for more than 1 year." The infant was diagnosed with YHFS due to the onset of extremely severe mental retardation, microcephaly, abnormal hearing, severe protein-energy malnutrition, congenital cataract, cleft palate (I°), congenital atrial septal defect, brain atrophy, hydrocephalus, and brain hypoplasia. The whole exon sequencing revealed two compound heterozygous mutations, including a likely pathogenic TELO2 variant, c.2245A > T (p.K749X) from her mother and an uncertain variant, c.2299C > T (p.R767C) from her father, validated by Sanger sequencing. After bilateral cataract surgery, the infant obtained better visual acuity and showed more responses and interactions with her parents. Diagnosis and treatment of this case prompt that these TELO2 variants have not been reported, deepening the understanding of the molecular and genetic mechanism of YHFS in clinical practice.
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Cardiac tissue suffers much from sepsis, and the incidence of myocardial injury is high in septic patients. The treatment of sepsis myocardial injury (SMI) has been the focus of clinical medicine. Salidroside shows myocardial cell protection, anti-oxidation and anti- inflammation effects, and it is thought as one of the potential compounds to treat sepsis myocardial injury. However, its anti-inflammatory activity is lower and its pharmacokinetic properties are not ideal, which is far from clinical application. Here, a series of salidroside analogs were synthesized, and their bioactivities were evaluated from several aspects, including their anti-oxidant and anti-inflammatory activities in vitro and anti-sepsis myocardial injury activities in vivo. Of all the compounds which synthesized, compounds 2 and 3 exhibited stronger anti-inflammatory activities than the others; after treating LPS-stimulated RAW264.7 or H9c2 cells with each of them, the levels of IL-1ß, IL-6 and TNF-α were down-regulated in a dose-dependent manner. In the anti-oxidative stress injury test, compounds 2 and 3 not only markedly increased the survival rate of cells, and but also improved the cellular oxidative stress-related indicators MDA, SOD and cell damage marker LDH in a dose-dependent manner. In the LPS-induced septic rat myocardial injury models (in vivo), the two compounds also showed good bioactivities. They also reduced the expression of IL-1ß, IL-6 and TNF-α, and blocked cell damage by suppressing overhauled oxidation in septic rats. In addition, the myocardial injury was significantly improved and the inflammatory infiltration was reduced after treatment with the two compounds. In conclusion, the salidroside analogs (2 and 3) showed promising therapeutical effect on septic myocardial injury in LPS-model rats, and they could be good candidates for clinical trials against inflammation and septic myocardial injury.
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Sepsis , Factor de Necrosis Tumoral alfa , Ratas , Animales , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Antiinflamatorios/farmacología , Sepsis/tratamiento farmacológico , InflamaciónRESUMEN
Wheel flats are amongst the most common local surface defect in railway wheels, which can result in repetitive high wheel-rail contact forces and thus lead to rapid deterioration and possible failure of wheels and rails if not detected at an early stage. The timely and accurate detection of wheel flats is of great significance to ensure the safety of train operation and reduce maintenance costs. In recent years, with the increase of train speed and load capacity, wheel flat detection is facing greater challenges. This paper focuses on the review of wheel flat detection techniques and flat signal processing methods based on wayside deployment in recent years. Commonly used wheel flat detection methods, including sound-based methods, image-based methods, and stress-based methods are introduced and summarized. The advantages and disadvantages of these methods are discussed and concluded. In addition, the flat signal processing methods corresponding to different wheel flat detection techniques are also summarized and discussed. According to the review, we believe that the development direction of the wheel flat detection system is gradually moving towards device simplification, multi-sensor fusion, high algorithm accuracy, and operational intelligence. With continuous development of machine learning algorithms and constant perfection of railway databases, wheel flat detection based on machine learning algorithms will be the development trend in the future.
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The phytohormones, jasmonates (JAs), mediate many plant developmental processes and their responses to important environmental stresses, such as herbivore attack. Bioactive JAs are perceived by CORONATINE INSENSITIVE (COI)-receptors, and associated JAZ proteins, to activate downstream responses. To date, the JA receptors of the important monocot crop plant, rice, remain to be explored. Here, we studied all three rice COI proteins, OsCOI1a, OsCOI1b, and OsCOI2, by ligand binding, genome editing, and phenotyping and examining some of the responsible mechanisms for the different responses. OsCOI2 binds to most individual OsJAZs in the presence of endogenous JA ligands, as OsCOI1a /1b do, albeit with greater partner selectivity. Single mutants of each OsCOI and OsCOI1a/1b double mutants were constructed by CRIPSR-Cas9-based genome editing and used to phenotype developmental and defense responses. OsCOI1b is involved in root growth and grain-size control and plays overlapping roles with OsCOI1a in spikelet development, while OsCOI2 regulates leaf senescence, male sterility, root growth, and grain size. All OsCOIs mediated resistance to the devastating rice pest, the brown planthopper. However, the defense sectors regulated by OsCOI1a/1b and OsCOI2 clearly differed. Our results revealed that all three OsCOIs are functional JA receptors that play diverse roles in regulating downstream JA responses.
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Proteínas de Arabidopsis , Arabidopsis , Oryza , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Plantas/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
OBJECTIVE: This study aimed to investigate the prevalence characteristics of human papillomavirus (HPV) infections in 29,508 female cases in Jinshan District, Shanghai. MATERIALS AND METHODS: The current research represents a retrospective study that included 29,508 women who received cervical screening in the Jinshan Branch of Shanghai Sixth People's Hospital from 2010 to 2020. The overall prevalence, distribution types, age-specific prevalence and annual trends were analysed. RESULTS: The overall HPV infection rate among the patients was 21.97%. They were primarily high-risk HPV (HR-HPV) infections (20.30%) and single HPV infections (15.91%). A general decline in HPV and HR-HPV prevalence was observed with time from 33.52% to 25.45% in 2011 to 21.47% and 20.18% in 2020. The most common HPV genotypes were HPV52, HPV16, HPV58, HPV51, HPV53 and HPV68. The infection rates of HPV genotypes, including HPV6, HPV11, HPV16, HPV18, HPV31, HPV33, HPV35, HPV39, HPV42, HPV43, HPV66 and HPV68, showed overall declines across different years. The age-specific prevalence of total HPV and HR-HPV infections formed an approximate U-shaped curve with two peaks, one in the ≥55 age group (29.75%, 28.43%) and the other in the <25 age group (22.93%, 20.85%). Both total HPV and HR-HPV infection rates decreased to their lowest in the 25-34-year age groups. CONCLUSIONS: The prevalence of HPV infections showed a downward tendency with time. Single HPV genotype infections and HR-HPV infections were predominantly detected. The after prevalent characteristics of HPV can help to guide HPV vaccinations and cervical cancer screenings: 1) non-HPV16/HPV18 H R-HPV genotypes were prevalent; 2) non-vaccine-covered HPV53, HPV51 and HPV68 were also prevalent; 3) women above the age of 55 years had the highest HPV and HR-HPV infection rates.
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Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Detección Precoz del Cáncer , Estudios Retrospectivos , Genotipo , China/epidemiología , Papillomaviridae/genética , Papillomavirus Humano 16/genéticaRESUMEN
Nanofiltration (NF) is an effective technology for removing trace organic contaminants (TrOCs), while the inherent trade-off effect between water permeance and solute rejections hinders its widespread application in water treatment. Herein, we propose a novel scheme of "monomers with sacrificial groups" to regulate the microstructure of the polyamide active layer via introducing a hydrolyzable ester group onto piperazine to control the diffusion and interfacial polymerization process. The achieved benefits include narrowing the pore size, improving the interpore connectivity, enhancing the microporosity, and reducing the active layer thickness, which collectively realized the simultaneous improvement of water permeance and enhancement of TrOCs rejection performance. The resulting membranes were superior to both the control and commercial membranes, especially in water-TrOCs selectivity. The effects of using the new monomers on the membrane physicochemical properties were systematically studied, and underlying mechanisms for the enhanced separation performance were further revealed by simulating the polymerization process through density functional theory calculation and measuring the trans-interface diffusion rate of monomers. This study demonstrates a novel promising NF membrane synthesis strategy by designing the structure of reaction monomers for achieving excellent rejection of TrOCs with a low energy input in water treatment.
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Quasi-optical mode conversion technology plays a very important role in the development of high-power terahertz radiation sources. The ability of metamaterials to manipulate wave-front paves a new way in the field of quasi-optical mode conversion. In this paper, the approach for quasi-optical mode conversion by all-dielectric metalens and polarization conversion is proposed and investigated. Three metalens are designed to converter cylindrical waveguide TE01 mode to linear polarized (LP), left-hand circularly polarized (LHCP), and right-hand circularly polarized (RHCP) Gaussian beams at 350â GHz. Electromagnetic simulations show that the Gaussian mode contents of output waves from three metalens are all over 98% with high polarization contents. Furthermore, a metalens is designed for dual circularly polarized (DCP) which could convert cylindrical waveguide TE01 mode to LHCP and RHCP simultaneously. This work unveils the potential application for metalens in terahertz region.
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The ignition methods used by micro-radio frequency (RF) ion thrusters have a disadvantage, that is, the starting voltage and flow rate are obviously higher than the rated value, which will easily damage the grid after long-term use. To decrease the starting voltage and flow and reduce the damage to the grid, a new ignition system is proposed in this paper. This system uses an intake pipe as the ground electrode, has an inductance coil and a pre-ionization chamber, and enables the miniature RF ion thruster (Harbin Institute of Technology's RF Ion Thruster 4, HRIT-4) to ignite at the rated voltage and flow by means of strong electric field breakdown and electromagnetic coupling. The experimental results show that when the flow rate is 1.0 SCCM, the ignition voltage is lower than 1900 V, and when the flow rate is 1.5 SCCM, the ignition voltage is lower than 1400 V.
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BACKGROUND: It is worrisome that several pollutants can enhance the abundance of antibiotic resistance genes (ARGs) in the environment, including agricultural fungicides. As an important bioindicator for environmental risk assessment, earthworm is still a neglected focus that the effects of the fungicide carbendazim (CBD) residues on the gut microbiome and resistome are largely unknown. In this study, Eisenia fetida was selected to investigate the effects of CBD in the soil-earthworm systems using shotgun metagenomics and qPCR methods. RESULTS: CBD could significantly perturb bacterial community and enrich specific bacteria mainly belonging to the phylum Actinobacteria. More importantly, CBD could serve as a co-selective agent to elevate the abundance and diversity of ARGs, particularly for some specific types (e.g., multidrug, glycopeptide, tetracycline, and rifamycin resistance genes) in the earthworm gut. Additionally, host tracking analysis suggested that ARGs were mainly carried in some genera of the phyla Actinobacteria and Proteobacteria. Meanwhile, the level of ARGs was positively relevant to the abundance of mobile genetic elements (MGEs) and some representative co-occurrence patterns of ARGs and MGEs (e.g., cmx-transposase and sul1-integrase) were further found on the metagenome-assembled contigs in the CBD treatments. CONCLUSIONS: It can be concluded that the enhancement effect of CBD on the resistome in the earthworm gut may be attributed to its stress on the gut microbiome and facilitation on the ARGs dissemination mediated by MGEs, which may provide a novel insight into the neglected ecotoxicological risk of the widely used agrochemicals on the gut resistome of earthworm dwelling in soil. Video abstract.