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Aquatic plants are a crucial component of the aquatic ecosystem in the Tibetan Plateau region. Researching the adaptability of plateau aquatic plants in photosynthesis to the plateau environment can enhance understanding of the operational mechanisms of plateau ecosystems, thereby providing a scientific basis for the protection and management of plateau aquatic ecosystems. This study presents an investigation of photosynthetic inorganic carbon utilization strategies and photosynthetic efficiency of 17 aquatic plants under natural growing conditions in Niyang River basin on the Tibetan Plateau. In pH-drift experiments, 10 of 17 species were able to utilize HCO3-, and environmental factors like water pH were shown to have a significant effect on the ability of the tested species to utilize HCO3-. Titratable acidity in the leaves of Stuckenia filiformis, Zannichellia palustris, Batrachium bungei, and Myriophyllum spicatum showed significant diurnal fluctuations at certain sampling sites, indicating the presence of CAM. In B. bungei, water pH positively correlated with CAM activity, while CO2 concentration negatively correlated with CAM activity. The chlorophyll fluorescence analysis revealed that aquatic plants inhabiting the Tibetan Plateau exhibited photosynthetic adaptations. In conclusion, the aquatic plants on the Tibetan Plateau employ diverse strategies for utilizing inorganic carbon during photosynthesis, exhibiting their flexible adaptability to the native high-altitude habitats of the Tibetan Plateau.
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Lignin hydrothermal silica-carbon material served as a backbone for MgCl2 activation to prepare lignin-based silicon/magnesia biochar (ALB/Si-Mg) for Cd2+, Pb2+, Cu2+, and Zn2+ removal from water and soil environment. Characterization studies revealed a 1017.71-fold increase in the specific surface area of ALB/Si-Mg compared to the original lignin biochar (ALB), producing abundant oxygen functional groups (OC-O, Si-O, Mg-O), and mineral matter (Mg2SiO4 and MgO). Crucially, batch adsorption experiments demonstrated that the adsorption capacity of ALB/Si-Mg for Cd2+, Pb2+, Cu2+, and Zn2+ was 848.17, 665.07, 151.84, and 245.78 mg/g, which were 29.09-140.45 times of the ALB. Soil remediation experiments showed that applying ALB/Si-Mg increased soil effective silicon (109.04%-450.2%) and soil exchangeable magnesium (276.41%-878.66%), enhanced plant photosynthesis, and notably reduced the bioavailability of heavy metals in soil as well as the content of heavy metals in Pakchoi, thereby promoting Pakchoi growth and development. The presence of oxygen-containing functional groups on ALB/Si-Mg, along with Mg2SiO4 and MgO nanoparticles, enhanced the adsorption capacity for heavy metals through the promotion of heavy metal precipitation, ion exchange, and complexation mechanisms. This study establishes the groundwork for the coupling of silica and magnesium elements in biochar and the remediation of composite heavy metal environmental pollution.
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Carvão Vegetal , Recuperação e Remediação Ambiental , Lignina , Metais Pesados , Dióxido de Silício , Metais Pesados/química , Carvão Vegetal/química , Dióxido de Silício/química , Lignina/química , Adsorção , Recuperação e Remediação Ambiental/métodos , Magnésio/química , Solo/química , Poluentes do Solo/químicaRESUMO
Microbial communities inhabiting sedimentary environments in river source regions serve as pivotal indicators of pristine river ecosystems. While the correlation between antibiotic resistome and pathogenicity with core gut bacteria in humans is well established, there exists a significant knowledge gap concerning the interaction of antibiotic resistance genes (ARGs) and human pathogenic bacteria (HPB) with specific microbes in river source basins, often referred to as "terrestrial gut". Understanding the microbial composition, including bacteria and resident genetic elements such as ARGs, HPB, Mobile Genetic Elements (MGEs), and Virulence Factors (VFs), within natural habitats against the backdrop of global change, is imperative. To address this gap, an enrichment-based culturomics complementary along with metagenomics was conducted in this study to characterize the microbial biobank and provide preliminary ecological insights into profiling the dissemination of ARGs in the Lancang River Source Basin. Based on our findings, in the main stream of the Lancang River Source Basin, 674 strains of bacteria, comprising 540 strains under anaerobic conditions and 124 under aerobic conditions, were successfully isolated. Among these, 98 species were identified as known species, while 4 were potential novel species. Of these 98 species, 30 were HPB relevant to human health. Additionally, bacA and bacitracin emerged as the most abundant ARGs and antibiotics in this river, respectively. Furthermore, the risk assessment of ARGs predominantly indicated the lowest risk rank (Rank â £) in terms of endangering human health. In summary, enrichment-based culturomics proved effective in isolating rare and unknown bacteria, particularly under anaerobic conditions. The emergence of ARGs showed limited correlation with MGEs, indicating minimal threats to human health within the main stream of the Lancang River Source Basin.
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Controlling light qualities have been acknowledged as an effective method to enhance the efficiency of phytoremediation, as light has a significant impact on plant growth. This study examined the effects of light qualities on cadmium (Cd) tolerance in aquatic plant Egeria densa using a combination of biochemical and transcriptomic approaches. The study revealed that E. densa exhibits higher resistance to Cd toxicity under red light (R) compared to blue light (B), as evidenced by a significant decrease in photosynthetic inhibition and damage to organelle ultrastructure. After Cd exposure, there was a significantly reduced Cd accumulation and enhanced levels of both glutathione reductase (GR) activity and glutathione (GSH), along with an increase in jasmonic acid (JA) in R-grown E. densa compared to B. Transcriptional analysis revealed that R caused an up-regulation of Cd transporter genes such as ABCG (G-type ATP-binding cassette transporter), ABCC (C-type ATP-binding cassette transporter), and CAX2 (Cation/H+ exchanger 2), while down-regulated the expression of HIPP26 (Heavy metal-associated isoprenylated plant protein 26), resulting in reduced Cd uptake and enhanced Cd exportation and sequestration into vacuoles. Moreover, the expression of genes involved in phytochromes and JA synthesis was up-regulated in Cd treated E. densa under R. In summary, the results suggest that R could limit Cd accumulation and improve antioxidant defense to mitigate Cd toxicity in E. densa, which might be attributed to the enhanced JA and phytochromes. This study provides a foundation for using light control methods with aquatic macrophytes to remediate heavy metal contamination in aquatic systems.
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Antioxidantes , Cádmio , Luz , Cádmio/toxicidade , Cádmio/metabolismo , Antioxidantes/metabolismo , Hydrocharitaceae/metabolismo , Hydrocharitaceae/efeitos dos fármacos , Hydrocharitaceae/efeitos da radiação , Oxilipinas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Ciclopentanos/metabolismo , Fotossíntese/efeitos dos fármacos , Glutationa/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Luz VermelhaRESUMO
Introduction: Position adherence of patients with Pars Plana Vitrectomy with Silicone Oil Tamponade after discharge is of positive significance. However, patients undergoing a day surgery makes the quality of discharge teaching and readiness for hospital discharge is insufficient, which will influence their position adherence at home. Aim: This study aimed to find the correlation of discharge teaching, readiness for hospital discharge, and position adherence in patients who underwent PPV with silicone oil tamponade from the day ward. Methods: This was a cross-sectional survey. One hundred ninety-four patients with day surgery were recruited by convenient sampling from Zhongshan Ophthalmic Center, China. Data were collected using the quality of discharge teaching scale, readiness for hospital discharge scale, and position adherence scale. Results: Patients' education level, residence, poor postoperative vision, ophthalmic surgery history, and quality of discharge teaching are the main factors of readiness for discharge. Only 41(21%) patients had good position adherence, and education level and readiness for discharge are the main factors of position adherence. Discussion: Discharge teaching improves patients' knowledge and competence of self-care and helps patients prepare for the transition from hospital to home, and readiness for hospital discharge significantly influences position adherence after discharge and indirectly plays a vital role in postoperative vision recovery and surgical effect.
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The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb2O5thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb2O5with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb2O5compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb2O5exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb2O5make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb2O5are 0.28 S/mWcm-2and 1.68 × 1011Jones respectively. The sensor response towards NO2gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb2O5exhibits high selectivity towards the NO2gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb2O5. The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life.
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The vast majority of processes in the carbon and nitrogen cycles are driven by microorganisms. The nitrite-dependent anaerobic oxidation of methane (N-DAMO) process links carbon and nitrogen cycles, offering a novel approach for the simultaneous reduction of methane emissions and nitrite pollution. However, there is currently no comprehensive summary of the current status of the N-DAMO process in natural aquatic environments. Therefore, our study aims to fill this knowledge gap by conducting a comprehensive review of the global research trends in N-DAMO processes in various aquatic environments (excluding artificial bioreactors). Our review mainly focused on molecular identification, global study sites, and their interactions with other elemental cycling processes. Furthermore, we performed a data integration analysis to unveil the effects of key environmental factors on the abundance of N-DAMO bacteria and the rate of N-DAMO process. By combining the findings from the literature review and data integration analysis, we proposed future research perspectives on N-DAMO processes in global aquatic environments. Our overarching goal is to advance the understanding of the N-DAMO process and its role in synergistically reducing carbon emissions and removing nitrogen. By doing so, we aim to make a significant contribution to the timely achievement of China's carbon peak and carbon neutrality targets.
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Metano , Nitritos , Anaerobiose , Bactérias Anaeróbias , Oxirredução , Reatores Biológicos , Carbono , DesnitrificaçãoRESUMO
AIM: To explore the factors influencing individuals' willingness to participate in ophthalmic clinical trials. METHODS: A questionnaire survey was conducted from January to April 2021 among patients and their family members at Zhongshan Ophthalmic Center, Sun Yat-sen University, in Guangzhou, China. The survey gathered data on respondents' willingness, demographic and socioeconomic profiles, as well as their reasons and concerns regarding engagement in clinical trials. RESULTS: Of the 1078 residents surveyed (mean age 31.2±13.1y; 65.8% females) in Guangzhou, 749 (69.5%) expressed a willingness to participate in future ophthalmic clinical trials. Specific characteristics associated with greater willingness included a younger age, lower annual income, higher education, prior participation experience, previous ophthalmic treatment, and a better understanding of clinical trials. With the exception of age, these characteristics were significantly linked to a higher willingness. The primary barrier to participation, expressed by 64.8% of those willing and 54.4% of those unwilling, was "Uncertain efficacy". In terms of motivations, the willing group ranked "Better therapeutic benefits" (35.0%), "Professional monitoring" (34.3%), and "Trust in healthcare professionals" (33.1%) as their top three reasons, whereas the unwilling participants indicated "Full comprehension of the protocol" (46.2%) as the key facilitator. CONCLUSION: This study reveals a substantial willingness to participate in ophthalmic clinical trials and demonstrates the predictive role of demographic and socioeconomic factors. Variations in motivators and concerns between willing and unwilling participants highlight the significance of tailored recruitment strategies. Importantly, the need for and trust in healthcare professionals stand out as powerful motivations, underscoring the importance of enhancing physician-patient relationships, adopting patient-centered communication approaches, and addressing individualized needs to improve accrual rates.
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The purpose of the study was to determine the associations of self-perception, motor skills, and clinical features of young school-age children with glaucoma (CG). This is a cross-sectional observational study. Children from preschool to second grade, including CG (N = 19), children with amblyopia (CA, N = 28), and controls (N = 32), completed the Manual Dexterity and Aiming and Catching Scales of the Movement Assessment Battery for Children-2nd edition (MABC-2), including Manual Dexterity, Aiming and Catching, and Balance. CG, CA, and their parent completed the Pictorial Scale of Perceived Competence and Social Acceptance for Young Children, respectively, assessing the child's cognitive competence, peer acceptance, physical competence, and maternal acceptance. The Kruskal-Wallis H test and Bonferroni post hoc test compared motor skills among groups. Spearman's correlation analysis evaluated the correlations between motor skills, self-perception, and clinical features. The CG reported lower peer acceptance than CA (P = 0.040), and the parents of CG reported lower cognitive competence than CG reported (P = 0.046). Compared with controls, CG had worse performance of Aiming and Catching, and Balance (P = 0.018 and P = 0.001), and CA had worse performance of Balance (P = 0.009). The motor skills were comparable between CG and CA. For CG, older age correlated with worse competence of Aiming and Catching (r = - 0.620, P = 0.005), better best-corrected visual acuity of better-seeing eye correlated with higher competence of Manual Dexterity and Balance (r = - 0.494, P = 0.032, and r = - 0.516, P = 0.024), and longer duration of glaucoma correlated with worse competence of Manual Dexterity (r = - 0.487, P = 0.034). CONCLUSION: Glaucoma and amblyopia have significant negative impacts on children's daily motor skills. The acuity of a better-seeing eye is an important factor influencing motor movement. TRIAL REGISTRATION: ClinicalTrials.gov identifier, ChiCTR2100050415. WHAT IS KNOWN: ⢠The state of mental health in early childhood influences the development of their future personality and physical development. The prognosis and management of glaucoma may seriously impair the mental health development of the affected children. However, the exploration of psychological aspects and motor movement of childhood glaucoma was limited. WHAT IS NEW: ⢠Children with glaucoma have impaired motor skills and self-perception development, especially in terms of peer socialization.
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Ambliopia , Glaucoma , Percepção de Movimento , Criança , Humanos , Pré-Escolar , Ambliopia/psicologia , Estudos Transversais , Destreza Motora , Autoimagem , Glaucoma/diagnósticoRESUMO
Importance: Visual impairment in working-age individuals can affect their general health and employment prospects, leading to decreased social and economic productivity and increased poverty rates. Nonetheless, investigations in this population appear to be limited. Objective: To investigate the trends of visual impairment prevalence and disability-adjusted life-years (DALYs) in working-age individuals from 1990 to 2019. Design, Setting, and Participants: This cross-sectional, population-based study used data for individuals of working age (15-64 years) from 204 countries and territories obtained from the Global Burden of Disease 2019 study. The data analysis was performed between May 1 and 10, 2023. Exposure: Visual impairment, defined as visual acuity of less than 6/18 (20/60) or near visual acuity of less than 6/12 (20/40) distance equivalent as determined by Snellen chart. Main Outcomes and Measures: Trends of visual impairment prevalence, DALYs, and corresponding estimated annual percent changes (EAPCs) from 1990 to 2019 were stratified according to region, nation, and sociodemographic index (SDI). Results: There were 437â¯539â¯484 (95% uncertainty interval [UI], 325â¯463â¯851-575â¯573â¯588) prevalent cases of visual impairment globally (53.12% female and 46.88% male) in 2019, representing an increase of 91.46% from 1990 (prevalent cases, 228â¯530â¯964; 95% UI, 172â¯515â¯833-297â¯118â¯596). Over 3 decades, visual impairment-associated DALYs increased from 7â¯601â¯852 (95% UI, 5â¯047â¯030-11â¯107â¯897) to 12â¯563â¯276 (95% UI, 8â¯278â¯866-18â¯961â¯723). Among the 5 SDI groups, the low-SDI group had the largest increase in DALYs (898 167 [95% UI, 597 161-1 301 931] in 1990 to 1 634 122 [95% UI, 1 079 102-2 444 381] in 2019). Regionally, the greatest increase in prevalence was observed in Eastern Europe (EAPC, 0.10; 95% CI, 0.02-0.19). Among all countries and territories, Nepal had the highest national prevalence of visual impairment per 100â¯000 population in 2019 (26â¯008.45; 95% UI, 19â¯987.35-32â¯482.09), while South Sudan had the highest DALY rate per 100â¯000 population (480.59; 95% UI, 316.06-697.06). Conclusions and Relevance: Despite the mild decrease in visual impairment prevalence rates in less-developed countries, these findings suggest that the number of prevalent cases globally has increased substantially, with discernible unfavorable patterns in developed regions. The findings support the notion that visual impairment in working-age individuals is a growing global health challenge. A better understanding of its epidemiology may facilitate the development of appropriate measures for prevention and treatment from both medical and social perspectives.
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Carga Global da Doença , Saúde Global , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Estudos Transversais , Prevalência , Transtornos da Visão/epidemiologia , IncidênciaRESUMO
Among the various pollutants detected in aquatic ecosystems, cadmium (Cd) is considered as one of the most hazardous. Freshwater macrophytes have been recognized as possible candidates for eliminating Cd from environment. Nevertheless, the impact of light quality on their ability to tolerate Cd toxicity remains unclear, and the underlying mechanisms have yet to be fully elucidated. In this study, we utilized physiological testing and metabolomics to explore the potential mechanisms by which light quality influences the ability of Egeria densa, a significant Cd hyperaccumulator, to withstand Cd toxicity. The study demonstrated that following Cd treatment, E. densa grown under red light exhibited superior photosynthetic efficiency compared to those grown under blue light, as evidenced by significantly increased photosynthetic rate, higher starch content, and greater activity of photosynthetic enzymes. Moreover, metabolomic analyses revealed that under Cd stress, E. densa grown under red light exhibited an enhanced glycolysis for increased energy production. Sucrose metabolism was also improved to generate sufficient sugar including glucose, fructose and mannose for osmotic adjustment. Moreover, under red light, the heightened production of α-ketoglutarate via tricarboxylic acid (TCA) cycle redirected nitrogen flow towards the synthesis of resilient substances such as γ-Aminobutyric Acid (GABA) and methionine. The production of these substances was â¼2.0 and 1.3 times greater than that of treatment with Cd under blue light, thereby improving E. densa's capacity to withstand Cd stress. This study represents the initial investigation into the possible mechanisms by which light quality influences the ability of E. densa to withstand Cd toxicity through regulating CN metabolism. Furthermore, these findings have the potential to improve phytoremediation strategies aimed at reducing Cd pollution.
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Cádmio , Poluentes Químicos da Água , Cádmio/toxicidade , Ecossistema , Luz Vermelha , Carbono , Poluentes Químicos da Água/toxicidade , Metabolismo Energético , NitrogênioRESUMO
Local feature extractions have been verified to be effective for person re-identification (re-ID) in recent literature. However, existing methods usually rely on extracting local features from single part of a pedestrian while neglecting the relationship of local features among different pedestrian images. As a result, local features contain limited information from one pedestrian image, and cannot benefit from other pedestrian images. In this paper, we propose a novel approach named Local Relation-Aware Graph Convolutional Network (LRGCN) to learn the relationship of local features among different pedestrian images. In order to completely describe the relationship of local features among different pedestrian images, we propose overlap graph and similarity graph. The overlap graph formulates the edge weight as the overlap node number in the node's neighborhoods so as to learn robust local features, and the similarity graph defines the edge weight as the similarity between the nodes to learn discriminative local features. To propagate the information for different kinds of nodes effectively, we propose the Structural Graph Convolution (SGConv) operation. Different from traditional graph convolution operations where all nodes share the same parameter matrix, SGConv learns different parameter matrices for the node itself and its neighbor nodes to improve the expressive power. We conduct comprehensive experiments to verify our method on four large-scale person re-ID databases, and the overall results show LRGCN exceeds the state-of-the-art methods.
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Cadmium (Cd) is highly toxic and widely distributed in aquatic systems due to its high solubility and mobility in water, which can severely inhibit the survival of aquatic macrophytes. The phytotoxicity of Cd depends on environmental factors; however, it remains unclear whether and how light quality affects its toxicity on aquatic macrophytes. In this study, we investigated the effects of Cd on aquatic macrophytes Potamogeton crispus under different light qualities (white, blue, and red light). We evaluated morphological and photo-physiological traits, as well as the cellular antioxidant defense system. Our findings indicate that P. crispus under Cd stress showed notable damage in leaf morphology, decreased photosynthetic efficiency, inhibited HCO3- uptake, and reduced antioxidant enzyme activities, as well as oxidative damage indicated by MDA accumulation and superoxide (O2-) overproduction. However, compared with white or red light under Cd stress, blue light reduced structural damage and oxidative stress caused by Cd while increasing pigment synthesis and photosynthetic efficiency, as well as increasing ascorbate peroxidase (APX) activity. In conclusion, the changes induced by blue light in P. crispus's photosynthesis and antioxidant system strengthen its tolerance to Cd. Further research on signal transmission in relation to light quality in Cd-exposed aquatic plants is still needed.
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Developing countries are struggling to balance the economic development and environment protection. This paper examines the impact of high-speed rail (HSR) on firm-level environmental performance in China. Using the staggered expansion of China's passenger-dedicated HSR and the panel data of Chinese manufacturing firm-level data from 2002 to 2012, we find that firms exhibit a lower level of chemical oxygen demand (COD) emissions after the opening of HSR. The average geographical slope of city is used as an instrumental variable to address the potential endogeneity problem of the HSR variable. Furthermore, the reduction effect of HSR introduction on firms' COD emission intensity is more pronounced for firms that located in eastern regions as well as technology-intensive and labor-intensive firms. Agglomeration economies, scale effects, and technological innovation are three plausible channels that allow HSR to promote firm environmental performance. Our paper provides new insights into the impacts of introduction of HSR on firm environmental performance and the development of green city.
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Comércio , Conservação dos Recursos Naturais , China , Cidades , Invenções , Política AmbientalRESUMO
In this work, a simple electrochemical oxidation method has been used to prepare p-typeß-Ga2O3nanoparticles. This method overcomes the problem of doping high energy gap semiconductors to form p-type. The electron holes ofß-Ga2O3were caused by oxygen vacancy (Vo) and showed the shorter lattice constant and preferred orientation in XRD analysis. The peak area of oxygen vacancy also reflects a higher ratio than n-type Ga2O3in x-ray photoelectron spectroscopy (XPS). The adsorption of reducing gas (CO, CH4, and H2) enhanced the resistance of theß-Ga2O3confirming the p-type character of NPs. The DFT calculations showed that oxygen vacancy leads to higher energy of the Fermi level and is near the valence band. The binding energy of Ga2O3and after interaction with gas molecular was also calculated which is analogous to our experimental data.
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Carbon and nitrogen metabolism are basic, but pivotal metabolic pathways in plants and are tightly coupled. Maintaining the balance of carbon and nitrogen metabolism is critical for plant survival. Comprehensively revealing the metabolic balance of carbon-nitrogen interactions is important and helpful for understanding the adaptation of freshwater plants to CO2 limited aqueous environment. A comprehensive metabolomics analysis combined with physiological measurement was performed in the freshwater plant Ottelia alismoides acclimated to high and low CO2, respectively, for a better understanding of how the carbon and nitrogen metabolic adjustment in freshwater plants respond to carbon limitation. The present results showed that low CO2 acclimated O. alismoides exhibited significant diurnal titratable acidity and malate fluctuations, as well as an opposite diel pattern of starch change and high enzymatic activities required for crassulacean acid metabolism (CAM) photosynthesis, which indicates that CAM was induced under low CO2. Moreover, the metabolomic analysis showed that most intermediates of glycolysis, pentose phosphate pathway (PPP) and tricarboxylic acid (TCA) cycle, were increased under low CO2, indicative of active respiration in low-CO2-treated O. alismoides. Meanwhile, the majority of amino acids involved in pathways of glutamate and arginine metabolism, aspartate metabolism, and the branched-chain amino acids (BCAAs) metabolism were significantly increased under low CO2. Notably, γ-aminobutyric acid (GABA) level was significantly higher in low CO2 conditions, indicating a typical response with GABA shunt compensated for energy deprivation at low CO2. Taken together, we conclude that in low-CO2-stressed O. alismoides, CAM photosynthesis was induced, leading to higher carbon and nitrogen as well as energy requirements. Correspondingly, the respiration was greatly fueled via numerous starch degradation to ensure CO2 fixation in dark, while accompanied by linked promoted N metabolism, presumably to produce energy and alternative carbon sources and nitrogenous substances for supporting the operation of CAM and enhancing tolerance for carbon limitation. This study not only helps to elucidate the regulating interaction between C and N metabolism to adapt to different CO2 but also provides novel insights into the effects of CO2 variation on the metabolic profiling of O. alismoides.
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Neurons convert external stimuli into action potentials, or spikes, and encode the contained information into the biological nervous system. Despite the complexity of neurons and the synaptic interactions in between, rate models are often adapted to describe neural encoding with modest success. However, it is not clear whether the firing rate, the reciprocal of the time interval between spikes, is sufficient to capture the essential features for the neuronal dynamics. Going beyond the usual relaxation dynamics in Ginzburg-Landau theory for statistical systems, we propose that neural activities can be captured by the U(1) dynamics, integrating the action potential and the "phase" of the neuron together. The gain function of the Hodgkin-Huxley neuron and the corresponding dynamical phase transitions can be described within the U(1) neuron framework. In addition, the phase dependence of the synaptic interactions is illustrated and the mapping to the Kinouchi-Copelli neuron is established. It suggests that the U(1) neuron is the minimal model for single-neuron activities and serves as the building block of the neuronal network for information processing.
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Modelos Neurológicos , Neurônios , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Adaptação Fisiológica , Simulação por ComputadorRESUMO
Aflatoxin B1 (AFB1) is one of the most harmful mycotoxins, raising serious global health and economic problems. Searching for biological approaches for effective and safe AFB1 degradation is imminent. In our study, Microbacterium proteolyticum B204 isolated from bovine faeces degraded 77% of AFB1 after 24 h, becoming the first reported bacteria from the Microbacterium family to possess AFB1 degradation characteristics. Temperature variation showed little effect on its degradation ratio, demonstrating high thermostability of 75% and 79% after boiling and sterilization, respectively. We suppose that the components playing a key role during this process were proteins, considering the decreased degradation rate caused by Proteinase K. Cell viability detection on HepG2 cells indicated that the degradation products were much less toxic than pure AFB1. Furthermore, B204 cell-free culture supernatant also degraded AFB1-contaminated food, such as peanuts, corn and cheese. These results suggested that this strain with AFB1 degradation properties could be a prospective candidate for application in the food and feed industries.
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Aflatoxina B1 , Arachis , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidade , Animais , Arachis/metabolismo , Bovinos , Fezes , Inativação Metabólica , MicrobacteriumRESUMO
In this work, we use a chemical method to design novel 2D-material/0D-quantum dot (MoS2/SnS) heterostructures. Furthermore, the unique 2D/0D heterostructure enhanced the NO2 gas-sensing capability 3 times and increased the sensing recoverability by more than 90%. Advanced characterization tools such as SEM, TEM, XRD, and AFM confirm the formation of MoS2/SnS heterojunction nanomaterials. Using AFM data, the average thickness of the MoS2 layer was found to be 5 nm. The highest sensor response of 0.33 with good repeatability was observed at 250 ppb of NO2. Sensing characterization reveals the ultra-fast response time, that is, 74 s, at 50 ppb of NO2. The limit of detection for detecting NO2 was also found to be very low, that is, 0.54 ppb, by using MoS2/SnS heterostructures. The theoretical calculations based on density functional theory well corroborated and quantified the intermolecular interaction and gas adsorption on the surface of MoS2/SnS.
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Pine needles are reliable passive bio-samplers that can be used to monitor atmospheric pollution levels. This study applied Pb isotope and multivariate statistical analyses to pine needles to examine the characteristics, sources, and ecological risks of atmospheric heavy metal pollution in the cities of the middle reaches of the Yangtze River, China. The heavy metal concentrations were higher than those measured in pine needles elsewhere in the world. They were higher in the metropolitan city (Wuhan) than in the medium-sized city (Yichang) and lowest in the natural setting (Shennongjia Forestry District), which is consistent with trends in urbanization and industrialization. Principal component analysis grouped the metals into three main sets associated with industrial activities and traffic sources. The Pb composition determined the main anthropogenic Pb sources were vehicle exhaust and industrial activities related to the lead-zinc ore, only a few of which were coal combustion. Three risk assessment indexes (pollution load index, ecological risk index, and bioconcentration factor) suggest that atmospheric heavy metals in the study area pose moderate environmental and health risks.