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Research Advances in the Control of Spider Mites Using Bioactive Substances of Biological Origin
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作者 Tongshu DAI Kaicheng LIU Yanjie LUO 《Asian Agricultural Research》 2025年第11期51-53,共3页
Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to th... Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development. 展开更多
关键词 Bioactive substances of BIOLOGICAL ORIGIN Spider MITE CONTROL RNA interference Plant-derived ACTIVE substances Microorganism-derived ACTIVE substances
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Reduction of iron oxide nanoparticles by Geobacter sulfurreducens PCA involves outer membrane proteins and secreted redox-active substances
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作者 Yifan Cui Xiaoyan Zhang +7 位作者 Peijie Yang Yanwei Liu Maoyong Song Yingying Guo Wentao Jiao Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2026年第1期767-774,共8页
Fe reducing bacteria(FRB),through extracellular electron transfer(EET)pathway,can reduce Fe(III)nanoparticles,thereby affecting the migration,transformation,and degradation of pollutants.However,the interaction of Fe(... Fe reducing bacteria(FRB),through extracellular electron transfer(EET)pathway,can reduce Fe(III)nanoparticles,thereby affecting the migration,transformation,and degradation of pollutants.However,the interaction of Fe(III)nanoparticles with the most commonly identified FRB,Geobacter sulfurreducens PCA,remains poorly understood.Herein,we demonstrated that the synergistic role of outer membrane proteins and periplasmic proteins in the EET process for-Fe_(2)O_(3),Fe3O4,and𝛽α-FeOOH nanoparticles by construction of multiple gene knockout strain.oxpG(involved in the type II secretion system)and omcST(outer membrane c-type cytochrome)medi-ated pathways accounted for approximately 67%of the total reduction of𝛼α-Fe_(2)O_(3) nanoparticles.The residual reduction of𝛼α-Fe_(2)O_(3) nanoparticles in∆oxpG-omcST strain was likely caused by redox-active substances in cell supernatant.Conversely,the reduction of dissolved Fe(III)was almost unaffected in∆oxpG-omcST strain at the same concentration.However,at high dissolved Fe(III)concentration,the reduction significantly decreased due to the formation of Fe(III)nanoparticles,suggesting that this EET process is specific to Fe(III)nanoparticles.Overall,our study provided a more comprehensive understanding for the EET pathways between G.sulfurreducens PCA and different Fe(III)species,enriching our knowledge on the role of microorganisms in iron biogeochemical cycles and remediation strategies of pollutants. 展开更多
关键词 Microbial Fe(III)reduction Fe(III)nanoparticles Extracellular electron transfer Redox-active substances Geobacter sulfurreducens PCA
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Psychoactive Substances:Transforming the Paradigm for Treating Mental Health Disorders in the Post‑Pandemic Era
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作者 Haojiang Zhai Yibo Wang Xiaohui Wang 《Neuroscience Bulletin》 2025年第3期536-538,共3页
Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,wit... Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,with~1 in 8 people,equivalent to 970 million individuals suffering from a mental disorder in 2019(https://vizhub.healthdata.org/gbd-results).Anxiety and depressive disorders are predominant,contributing significantly to the burden of mental health issues,according to the World Health Organization.The COVID-19 pandemic has further exacerbated this situation.It led to a notable upsurge in anxiety and major depressive disorders in 2020.Estimates indicate a 26%rise in anxiety and a 28%increase in depression within that year(https://www.who.int/publications/i/item/WHO-2019-nCoVSci_Brief-Mental_health-2022.1)[1]. 展开更多
关键词 psychoactive substances depressive disorders post pandemic era mental health disorders mental disorder global health challenge mental health problems ANXIETY
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Statistical Monitoring Method for Pesticides and Harmful Substances 被引量:1
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作者 Han Huaqiong Li Weige(China National Centre for Quality Supervision and Test of Feed Beijing 100081 P. R of China) 《中国农业科技导报》 CAS CSCD 1999年第1期71-73,共3页
A statistical monitoring method has been developedfor accurate, safety surveillance methods of γ-BHC resideueor harmful substances in foods or feeds. It is very importantfor safety monitoring and arbitrament inspecti... A statistical monitoring method has been developedfor accurate, safety surveillance methods of γ-BHC resideueor harmful substances in foods or feeds. It is very importantfor safety monitoring and arbitrament inspections. This paperintroduces a calculation formula by a six-point calibrationmethod and an example for detection of Y-BHC in corn.The method can guarantee the accuracy of the results,and it does very substantially reduce the probability of an er-ror by one-point calibration. 展开更多
关键词 STATISTICAL monitoring method PESTICIDE residueγ-BHC Harmful substances The statisticalexample Six-point CALIBRATION Single-pointcalibration
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Effects of NaCl stress on the biochemical substances in Bt cotton as well as on the growth and development and adult oviposition selectivity of Helicoverpa armigera 被引量:2
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作者 LUO Junyu ZHANG Shuai +6 位作者 ZHU Xiangzhen JI Jichao ZHANG Kaixin WANG Chunyi ZHANG Lijuan WANG Li CUI Jinlie 《Journal of Cotton Research》 2019年第1期17-25,共9页
Background:Recently,due to the development of food security strategies,cotton has been planted in inland saline-alkali dry soils or in coastal some saline-alkali soils in China.Under the condition,to comprehensively p... Background:Recently,due to the development of food security strategies,cotton has been planted in inland saline-alkali dry soils or in coastal some saline-alkali soils in China.Under the condition,to comprehensively prevent and control Helicoverpa armigera in cotton fields with saline-alkali soils,it is important to study the larval growth and development of H.armigero and to study adult oviposition selectivity in H.armigera adults that feed on NaCI-stNaCled cotton plants.Results:In this study,Bt cotton GK19 was used for the experimental group and its nontransgenic parent Simian 3 was used for the control to study the effects of biochemical substances in cotton as well as larval growth and development and adult oviposition selectivity of H.armigera.The experiments were performed by growing cotton indoors under NaCl stress at concentrations of 0 mmol-L^(-1),75 mmol-L^(-1)and 150 mmol-L^(-1),respectively.The results showed that the expression of Bt protein was significantly inhibited for NaCI-stressed Bt cotNaClThe content of soluble protein and K^(+)in the leaves of cotton were decreased,while the content of gossypol and Na+were increased.In addition,the 5th instar H.armigera larvae exhibited shorten the life span in a 13-day trial period.Under enclosure treatments and at different female densities,the adult oviposition of H.armigera decreased on high NaCI-stressed nontransgenic coNaCl,while the oviposition on Bt cotton tended to first increase but then decrease under low,moderate and high NaCl stress treatments.Conclusions:Under certain content ranges of NaCl stress treatments,larval of H.armigera growth and development,and adult oviposition were no significant difference in the change for a certain period.However,under high NaCl stress,larval growth,development and adult oviposition were affected,which may provide insights for the prevention and control of H.armigero for Bt cotton in saline-alkali soils. 展开更多
关键词 NaCl stress Bt cotton BIOCHEMICAL substance HELICOVERPA ARMIGERA Growth and development OVIPOSITION selectivity
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Evaluation of the secondary structures of protein in the extracellular polymeric substances extracted from activated sludge by different methods 被引量:8
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作者 Benyi Xiao Yu Liu +3 位作者 Meng Luo Tang Yang Xuesong Guo Hao Yi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第6期128-136,共9页
The changes of protein secondary structures in the extracellular polymeric substances(EPS) extracted from activated sludge by four different methods were studied by analyzing the amide I region(1700–1600 cm-1) of the... The changes of protein secondary structures in the extracellular polymeric substances(EPS) extracted from activated sludge by four different methods were studied by analyzing the amide I region(1700–1600 cm-1) of the Fourier transform infrared spectra and model protein test. The results showed the molecular weight distribution of organic matter extracted by centrifugation, heating and cation exchange resin(CER) was similar, while the EPS extracted by centrifugation(Control) and CER had similar fluorescent organic matter. The protein secondary structures of extracted EPS by the four methods were different. The similarities of protein secondary structures between the EPS extracted by CER with the Control were the highest among the four extracted EPS. Although the EPS yield extracted by formaldehyde + NaOH method were the highest, its protein secondary structures had the lowest similarity with those extracted by the Control. Additionally, the effects of centrifugation and CER extraction on the secondary structures of bovine serum albumin were also lower than that of other extraction processes. CER enables the second maximum extraction of EPS and maximum retention of the original secondary structure of proteins. 展开更多
关键词 Activated SLUDGE DIFFERENT extraction METHODS EXTRACELLULAR POLYMERIC substances Protein secondary structure
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Application of Coulometric Titration for the Certification of Primary Reference Materials of Pure Substances
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作者 Gennady I. Terentiev Alena V. Sobina +1 位作者 Alexandr J. Shimolin Veniamin M. Zyskin 《American Journal of Analytical Chemistry》 2014年第9期559-565,共7页
In this article, the block scheme and metrological characteristics of the State primary standard of the mass (molar) fraction and mass (molar) concentration of the component in the liquid and solid substances and mate... In this article, the block scheme and metrological characteristics of the State primary standard of the mass (molar) fraction and mass (molar) concentration of the component in the liquid and solid substances and materials based on coulometric titration GET 176-2010 are given. Primary reference materials certified by coulometric titration in the Ural Scientific and Research Institute for Metrology include eight certified reference materials (CRMs) of pure solid substances (mostly salts of sodium or potassium) and one hydrochloric acid solution CRM. The metrological characteristics of these reference materials and the scheme of their application in titrimetric analysis are shown. The expanded uncertainty of the certified value (mass fraction for the solid substances or molar concentration for the solution) is in the range from 0.018% to 0.05%. Information about two primary reference materials of high purity iron and lead nitrate certified by controlled-potential coulometry with expanded uncertainty from 0.04% to 0.07% is also given. 展开更多
关键词 Coulometric TITRATION Controlled-Potential COULOMETRY PRIMARY REFERENCE Materials High PURITY substances State PRIMARY Standard
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The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
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作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 Genetic Code CODON Populations Junk DNA Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME DNA SEQUENCE Phi the Golden Ratio Fibonacci NUMBERS Information Theory SYMMETRY Cellular Automata Chargaffs CODON Level SYMMETRY Principle Fractal Self-Similarity e Eulers Number Pi form and Substance Redundancy Encryption
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Shining a light on environmental science:Recent advances in SERS technology for rapid detection of persistent toxic substances 被引量:2
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作者 Zhenli Sun Xunlong Ji +1 位作者 Shaoyu Lu Jingjing Du 《Journal of Environmental Sciences》 2025年第7期251-263,共13页
Persistent toxic substances(PTS)represent a paramount environmental issue in the 21st century.Understanding the concentrations and forms of PTS in the environment is crucial for accurately assessing their environmenta... Persistent toxic substances(PTS)represent a paramount environmental issue in the 21st century.Understanding the concentrations and forms of PTS in the environment is crucial for accurately assessing their environmental health impacts.This article presents a concise overview of the components of PTS,pertinent environmental regulations,and conventional detection methodologies.Additionally,we offer an in-depth review of the principles,development,and practical applications of surface-enhanced Raman scattering(SERS)in environmental monitoring,emphasizing the advancements in detecting trace amounts of PTS in complex environmental matrices.Recent progress in enhancing SERS sensitivity,improving selectivity,and practical implementations are detailed,showcasing innovative materials and methods.Integrating SERS with advanced algorithms are highlighted as pivotal areas for future research. 展开更多
关键词 Persistent toxic substances Surface-enhanced Raman scattering Environmental monitoring Public health Sensitivity SPECIFICITY
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Roles of extracellular polymeric substances in arsenic accumulation and detoxification by cell wall intact and mutant strains of Chlamydomonas reinhardtii 被引量:1
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作者 Sadiq Naveed Qingnan Yu +3 位作者 Katarzyna Szewczuk-Karpisz Chunhua Zhang Shafeeq-Ur Rahman Ying Ge 《Journal of Environmental Sciences》 2025年第6期142-154,共13页
Arsenic(As)pollution seriously threatens human and ecological health.Microalgal cell wall and extracellular polymeric substances(EPS)are known to interactwith As,but their roles in the As resistance,accumulation and s... Arsenic(As)pollution seriously threatens human and ecological health.Microalgal cell wall and extracellular polymeric substances(EPS)are known to interactwith As,but their roles in the As resistance,accumulation and speciation inmicroalgae remain unclear.Here,we used two strains of Chlamydomonas reinhardtii,namely CC-125(wild type)and CC-503(cell walldeficientmutant),to examine the algal growth,EPS synthesis,As adsorption,absorption and transformation under 10–1000μg/L As(III)and As(V)treatments for 96 h.In both strains,the As absorption increased after the EPS removal,but the growth,As adsorption,and transformation of C.reinhardtii declined.The CC-125 strain was more tolerant to As stress and more efficient in EPS production,As accumulation,and redox transformation than CC-503,irrespective of EPS presence or absence.Three-dimension excitation-emission matrix(3DEEM)and attenuated total reflectance infrared spectroscopy(ATR-IR)analyses showed that As was bound with functional groups in the EPS and cell wall,such as-COOH,NH and-OH in proteins,polysaccharides and amino acids.Together,this study demonstrated that EPS and cell wall acted as barriers to lower the As uptake by C.reinhardtii.However,the cell wall mutant strain wasmore susceptible to As toxicity due to lower EPS induction and higher As absorption. 展开更多
关键词 Extracellular polymeric substances Cell wall ARSENIC ACCUMULATION Speciation MICROALGAE
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THE OVERLOOKED ECOSYSTEM DRIVING FORCE IN NON-EUTROPHICATED FRESHWATER SYSTEMS:DISSOLVED HUMIC SUBSTANCES-A SHORT REVIEW AND OUTLOOK
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作者 Christian E.W. Steinberg 《水生生物学报》 CAS CSCD 北大核心 2006年第6期721-733,共13页
This review starts with the description of the quantitative significance of dissolved organic material in general and dissolved humic substances (HS) in particular in various ecosystems. Despite their high quantities,... This review starts with the description of the quantitative significance of dissolved organic material in general and dissolved humic substances (HS) in particular in various ecosystems. Despite their high quantities, the knowledge about the role of HS is still very low and full of old, but still recycled paradigms. HS are thought to be inert or at least refractory and too large to be taken up by aquatic organisms. Instead, I present evidence that dissolved HS that mainly derives from the terrestrial environment, are taken up and directly and/or indirectly interfere with freshwater organisms and, thus, structure biocenoses. Relatively well known is in the meantime the fuelling function of allochthonous HS, which, upon irradiation, release fatty acids, which serve as substrates for microbial growth. This is an indirect effect of HS. Microbes, in turn, are food for mixotrophic algae and (heterotrophic) zooplankton. Thus, non-eutrophicated freshwaters are net-heterotrophic, meaning that respiration exceeds primary production. Furthermore, model calculations exemplify that only a very small portion of the terrestrial production is sufficient to cause net-heterotrophy in these freshwater bodies. But, recent papers show also that due to different stoichiometries the maximal plankton biomass production with algae or mixotrophs is higher than with bacteria. Very recently, several direct effects of HS have been elucidated. Among them are:induction of chaperons (stress shock proteins), induction and modulation of biotransformation enzymes, modulation (mainly inhibition) of photosynthetic oxygen release of aquatic plants, production of an internal oxidative stress, modulation of the offspring numbers in the nematode Caenorhabditis elegans[WTBZ], feminization of fish and amphibs, interference within the thyroid system, and action as chemical attractant to C. elegans. We are still in the phase of identifying the various physiological, biochemical, and molecular-biological effects. Hence, the ecological and ecophysiological significance of these HS-mediated effects still remain somewhat obscure. Nevertheless, HS appear generally to have an impact on the individual as well as on the community and even ecosystem level comparable to that of, for instance, nutrients. 展开更多
关键词 Humic substances Modulation of sex ratio Hormone-like effect Chemical attractant BIOTRANSFORMATION Oxidative stress Direct effects of humic substances Indirect effects of humic substances Net-heterotrophy Forest stocking
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Purification and Activity of Antibacterial Substances Derived from Soil Streptomyces sp.CaiF1
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作者 杨辉 彭桂香 +1 位作者 曾建民 谭志远 《Agricultural Science & Technology》 CAS 2012年第7期1460-1464,共5页
[Objective] This study aimed to separate and purify antibacterial substances from soil Streptomyces sp. CaiF1, and to explore the activities of this substance. [Method] The antibacterial substances were separated and ... [Objective] This study aimed to separate and purify antibacterial substances from soil Streptomyces sp. CaiF1, and to explore the activities of this substance. [Method] The antibacterial substances were separated and purified by Ethyl acetate extraction, macroporous adsorptive resin, silica gel chromatography and preparative high performance liquid chromatography (HPLC), and powdery mildew were taken as the indicating bacterial to study their activities. [Result] Antibacterial substances were purified and the stability analysis of the extracts from Streptomyces CaiF1 fermentation broth showed very stable at pH 2.0-pH 10.0, 100 ℃ and changed very little under UV treatment for 24 h. Inhibition rate of powdery mildew was 69.7%. [Conclusion] The purified antibacterial substances showed good stability, which provided theoretical foundation for their structural identifications and future applications. 展开更多
关键词 SOIL STREPTOMYCES sp. ANTIBACTERIAL substances SEPARATION and purifica- tion Stability
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Effect of Organic Fertilizer Doses on the Plant Growth,Essential Oil Production and Chemical Substances of "Carqueja" over Two Harvest Moments 被引量:1
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作者 Daniel Garcia Paulo Sérgio Siberti da Silva +3 位作者 Marcos Roberto Furlan Monica Tiho Chisaki Isobe Marcia Ortiz May Marques Lin Chau Ming 《Journal of Agricultural Science and Technology(B)》 2017年第2期114-124,共11页
This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response... This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response to five doses of organic fertilizer (0, 10, 20,30, 40 and 50 ton/ha) over two harvest moments-120 d and 242 d after transplanting (DAT). The work was carried out fromFebruary to October 2011 at the experimental farm of the Sao Paulo State University "Julio de Mesquita Filho" (UNESP), Brazil.The seedlings of B. trimera var. CPQBA-1 were respectively transplanted into experiment plots under six treatments: 0, 10, 20, 30,40 and 50 ton/ha of organic fertilizer. Each treatment had four replications and each plot consisted of 12 plants. Then they wereharvested at 120 DAT and 242 DAT, and the essential oil were extracted by hydrodistillation and analyzed by gas chromatograph.The results were subjected to analysis of variance and the means were analysed using Tukey's test (5%) followed by a regressionanalysis. The fertilizer dose significantly influenced the height of the plants in the second harvest, while the higher dose of organicfertilizer positively impacted the essential oil content in the first harvest. Also, the level of organic fertilizer was directly correlatedwith the production of dry matter during the regrowth. Twenty-seven substances were identified in the essential oil samples, and themajor components were: bicyclogermacrene, trans-caryophyllene, germacrene-D, spathulenol and caryophyllene oxide. Thesefindings suggest that to obtain higher yields of dry matter ofB. trimera, it should be harvested around 242 DAT and organic fertilizershould be applied approximately to 50 ton/ha. Furthermore, higher doses of organic fertilizer and harvest at 120 DAT is able toincrease the essential oil content. 展开更多
关键词 BACCHARIS trimera BRAZILIAN MEDICINAL plant dry matter CHEMICAL substances bicyclogermacrene.
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Characterization of atmospheric humic-like substances(HULIS)at a high elevation in North China:Abundance,molecular composition and optical properties
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作者 Chaofan Gong Xinghui Liu +4 位作者 Xiaoling Nie Xinmiao Xu Xinfeng Wang Likun Xue Yan Wang 《Journal of Environmental Sciences》 2025年第9期673-685,共13页
The optical absorption of large molecular compounds HULIS(humic-like substances)can significantly impact the aerosol light absorption and radiative forcing,influencing cloud condensation nuclei formation and thus the ... The optical absorption of large molecular compounds HULIS(humic-like substances)can significantly impact the aerosol light absorption and radiative forcing,influencing cloud condensation nuclei formation and thus the climate and atmospheric environment.This study collected aerosol(PM_(2.5))samples from the summit of Mount Tai in North China to investigate the concentration,molecular composition,and optical properties of HULIS.The average concentration of HULIS in the PM_(2.5) in this study was 1.26±0.54μg/m^(3),comprising for 56%of the water-soluble organic carbon(WSOC),with levels lower than urban areas but higher than other mountainous regions.Mass spectrometry revealed that CHO and CHON components,with high aromaticity and phenolic groups,are major contributors to absorption and fluorescence.These results indicate that HULIS is mainly composed of lignin and proteins/amino sugars,derived from combustion and secondary formation,and possesses a high light absorption capacity(withMAE365(mass absorption efficiency)and AAE(A˚ngstrom exponent)indices of 0.62m^(2)/g and 4.99,respectively).Parallel factor analysis identified three fluorescence components of HULIS,with proportions of 60.8%for less oxygen humic-like substances,21.0%for high oxygen humic-like substances,and 18.2%for protein-like substances.Our study highlights the significance of the light-absorbing capacity and secondary formation of HULIS at Mount Tai,laying the groundwork for investigation into the climate effects,formation mechanisms,and sources of HULIS generation. 展开更多
关键词 Humic-like substances(HULIS) PM_(2.5) ABUNDANCE Optical property FT-ICR MS Mount Tai
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Bioaccumulation of legacy and emerging per-and polyfluoroalkyl substances in hydroponic lettuce and risk assessment for human exposure
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作者 Qi Jin Yuwei Zhang +2 位作者 Yilin Gu Yali Shi Yaqi Cai 《Journal of Environmental Sciences》 2025年第8期378-389,共12页
Reclaimed water for irrigation or hydroponic cultivation provides exposure pathways for per-and polyfluoroalkyl substances(PFAS)to enter the human food chain.This study employed hydroponic methods to investigate the b... Reclaimed water for irrigation or hydroponic cultivation provides exposure pathways for per-and polyfluoroalkyl substances(PFAS)to enter the human food chain.This study employed hydroponic methods to investigate the behavior of legacy PFAS and emerging chlorinated polyfluoroalkyl ether sulfonic acids(Cl-PFESAs)in lettuce grown under environment-related exposure levels and assessed the human exposure risks from consuming contaminated lettuce.Overall,PFAS in lettuce were concentration-dependent,with long-chain PFAS tending to accumulate in roots and short-chain PFAS accumulating more in shoots.The enrichment of PFAS in lettuce was jointly influenced by their chain length and polar functional groups.Specifically,the root concentration factors(RCFs)of PFAS generally increased with increasing chain length,and RCF values of most perfluoroalkanesulfonic acids(PFSAs)were significantly higher than those of perfluoroalkyl carboxylic acids(PFCAs)with the same chain length(p<0.01),while the translocation factors(TFs)exhibited opposite trends.RCF values of perfluorooctane sulfonate(PFOS)and its alternatives,Cl-PFESAs,were ranked as follows:8:2 Cl-PFESA(mean:139)>6:2 Cl-PFESA(28.6)>PFOS(25.7),which was attributed to the increased molecular size and hydrophobicity resulting from the insertion of ether bonds and additional CF2 in 8:2 Cl-PFESA.Notably,TF value of 8:2 Cl-PFESA(mean:0.007)was the smallest among all PFAS,indicating 8:2 Cl-PFESA was difficult to transfer to nutritional compartments.Adults and children would exceed the most conservative health-based reference dose(RfD)by consuming approximately 15.9–148 g and 7.92–74.0 g of contaminated lettuce per day,implying high health risks. 展开更多
关键词 Chlorinated polyfluoroalkyl ether sulfonic acids Legacy per-and polyfluoroalkyl substances LETTUCE HYDROPONICS Human exposure risk
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Is there an Association between Per-and Poly-Fluoroalkyl Substances and Serum Pepsinogens?Evidence from Linear Regression and Bayesian Kernel Machine Regression Analyses
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作者 Jing Wu Shenglan Yang +2 位作者 Yiyan Wang Yuzhong Yan Ming Li 《Biomedical and Environmental Sciences》 2025年第6期763-767,共5页
Gastric cancer is the third leading cause of cancer-related mortality and remains a major global health issue^([1]).Annually,approximately 479,000individuals in China are diagnosed with gastric cancer,accounting for a... Gastric cancer is the third leading cause of cancer-related mortality and remains a major global health issue^([1]).Annually,approximately 479,000individuals in China are diagnosed with gastric cancer,accounting for almost 45%of all new cases worldwide^([2]). 展开更多
关键词 Bayesian kernel machine regression gastric canceraccounting gastric cancer per poly fluoroalkyl substances serum pepsinogens linear regression
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Effect of ulinastatin on vasoactive substances, oxidative stress and inflammatory response in patients with acute exacerbation of COPD
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作者 Chun-Lan Huang 《Journal of Hainan Medical University》 2017年第17期33-36,共4页
Objective:To study the effect of ulinastatin on vasoactive substances, oxidative stress and inflammatory response in patients with acute exacerbation of COPD.Methods:Patients with acute exacerbation of COPD who were t... Objective:To study the effect of ulinastatin on vasoactive substances, oxidative stress and inflammatory response in patients with acute exacerbation of COPD.Methods:Patients with acute exacerbation of COPD who were treated in Chengdu Fifth People's Hospital between August 2013 and July 2016 were selected as the research subjects and randomly divided into ulinastatin group and normal control group who received ulinastatin combined with conventional therapy and conventional therapy respectively. The serum contents of vasoactive substances, stress response hormones, oxidative stress products and inflammatory response mediators were detected before treatment and 7 d after treatment.Results: 7 d after treatment, serum D-D, AT-II, pro-BNP, ACTH, FC, NE, MDA, 8-iso-PG, HSP27, HSP70, PCT, CRP, CCL18 and MSP contents of both groups of patients were significantly lower than those before treatment while TT3 and TT4 contents were significantly higher than those before treatment;serum D-D, AT-II, pro-BNP, ACTH, FC, NE, MDA, 8-iso-PG, HSP27, HSP70, PCT, CRP, CCL18 and MSP contents of ulinastatin group 7 d after treatment were significantly lower than those of normal control group while TT3 and TT4 contents were significantly higher than those of normal control group.Conclusion:Ulinastatin therapy can correct the disturbance of vasoactive substances, and inhibit the oxidative stress and inflammatory response in patients with acute exacerbation of COPD. 展开更多
关键词 Chronic OBSTRUCTIVE PULMONARY disease ULINASTATIN Vasoactive substances OXIDATIVE stress INFLAMMATORY response
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Characterization of changes in extracellular polymeric substances and heavy metal speciation of waste activated sludge during typical oxidation solubilization processes 被引量:3
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作者 Qiongying Xu Huidi Wang +2 位作者 Qiandi Wang Weijun Zhang Dongsheng Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第6期146-158,共13页
Biopolymer solubilization is considered to be the rate-limiting stage of anaerobic digestion of waste activated sludge(WAS). Oxidation processes have been proven to be effective in disrupting sludge flocs and causing ... Biopolymer solubilization is considered to be the rate-limiting stage of anaerobic digestion of waste activated sludge(WAS). Oxidation processes have been proven to be effective in disrupting sludge flocs and causing solubilization of the solid biopolymers. In this study,WAS was treated by NaNO2 or H2 O2 oxidation at p H of 2. The changes in extracellular polymeric substances properties and the speciation of heavy metals were investigated. The results revealed that both NaNO2 and H2 O2 treatments were effective in solubilizing organics in WAS, while the conversion of biopolymers in the two treatment processes was different. Free nitrous acid destroyed the gel network structure of EPS, and organic materials were released from the solid phase to the supernatant. Indigenous peroxidase catalyzed H2 O2 to produce hydroxyl radicals which caused significant solubilization of biopolymers, and the protein-like substances were further degraded into micro-molecule polypeptides or amino acids at high dosages of H2 O2. During the oxidation processes, Zn, Cd and Cu, with excellent mobility, tended to migrate to the supernatant, and thus were easy to remove through the liquid–solid separation process. Ni and As showed moderate migration ability, of which the residual fraction tended to transform into reducible and soluble fractions. With poor mobility, Cr and Pb mainly existed in the forms of residual and oxidizable fractions, which were difficult to dissolve and remove from WAS. Both NaNO2 and H2 O2 treatment resulted in the enhancement of sludge solubilization efficiency and heavy metal mobility in WAS, but different heavy metals showed distinct migration and transformation behaviors. 展开更多
关键词 EXTRACELLULAR POLYMERIC substances(EPS) OXIDATION Biopolymers SOLUBILIZATION BIODEGRADABILITY Heavy metals
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The microbial community and flavour substances of off-flavoured rice sour soup during storage
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作者 Xiuli Li Na Liu +3 位作者 Likang Qin Ting Zhu Ruyue Xiao Song Miao 《Food Science and Human Wellness》 2025年第8期3280-3293,共14页
Fermented sour soup is a unique traditional sour food of the Miao and Dong ethnic groups in China.However,due to the commonly used traditional fermentation,the unstable fluctuation of microbial community often leads t... Fermented sour soup is a unique traditional sour food of the Miao and Dong ethnic groups in China.However,due to the commonly used traditional fermentation,the unstable fluctuation of microbial community often leads to some unpleasant inherent off-flavours in rice sour soup.In this study,the microbial composition and volatile flavour components of off-flavour and normal rice sour soup were examined by high-throughput sequencing and headspace solid-phase microextraction coupled with gas chromatography mass spectrometry.Then,based on Pearson correlation coefficients,the correlations between fungi and bacteria and those between core microorganisms and key volatile flavour components were investigated.The dominant fungal genera included Candida,Dekkera,Pichia,Rhizopus,and Issatchenkia,whereas the dominant bacterial genera included Lactobacillus,Pectinatus,Bifidobacterium,Pseudomonas,and Acetobacter.Compared to normal rice sour soup,off-flavoured rice sour soup contained the significantly increased relative abundance of Candida and the significantly decreased relative abundance of Dkkera.In addition,80 volatile flavour compounds detected in off-flavoured rice sour soup,mainly including esters,acids,and alcohols,were different from those detected in normal rice sour soup.Especially,some substances were only detected in off-flavoured rice sour soup,such as 1-hexanol(68-207μg/kg),butyric acid(20-92μg/kg)and heptanoic acid(12-45μg/kg),which might be the main source of off-flavours.These results provide new ideas and strategies of removing or abating odour from fermented rice sour soup. 展开更多
关键词 FERMENTATION Rice sour soup Microbial community Flavour substances OFF-FLAVOUR
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Proteomic insights from extracellular vesicles into the molecular mechanisms of health effects induced by Per-and polyfluoroalkyl substances
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作者 Yanping Li Yadan Luo +8 位作者 Yang Liu Na Li Kai Huang Lingxiangyu Li Zhigang Li Chao Han Nali Zhu Yawei Wang Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期395-411,共17页
Per-and polyfluoroalkyl substances(PFASs)can induce a range of adverse health effects,with the precise molecularmechanisms remaining elusive.Extracellular vesicles(EVs)have demonstrated their potential to elucidate un... Per-and polyfluoroalkyl substances(PFASs)can induce a range of adverse health effects,with the precise molecularmechanisms remaining elusive.Extracellular vesicles(EVs)have demonstrated their potential to elucidate unknown molecular mechanisms.Building upon the close alignment of their biological functions with the observed health effects of PFASs,this study innovatively focuses on proteomic insights from EVs into the molecular mechanisms underlying the systemic health effects of PFASs.Through rat exposure experiments and proteomics technology,it not only demonstrated the occurrence of PFASs in EVs but also revealed the alterations in the serum EVs and the expression of their protein cargos following mixed exposure to PFASs,leading to changes in related pathways.These changes encompass various biological processes,including proteasome activity,immune response,cytoskeletal organization,oxidative stress,cell signaling,and nervous system function.Particularly noteworthy is the uncovering of the activation of the proteasome pathway,highlighting significant key contributing proteins.These novel findings provide a new perspective for exploring the molecularmechanism underlying the systemic health effects of PFASs and offer reliable screening for potential biomarkers.Additionally,comparisons with serum confirmed the potential of serum EVs as biological responders and measurable endpoints for evaluating PFASs-induced toxicity. 展开更多
关键词 Per-and polyfluoroalkyl substances Extracellular vesicles Health effects PROTEOMICS PROTEASOME
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