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1.
Environ Sci Technol ; 57(35): 13258-13266, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37616046

RESUMO

Electrochemically mediated Fe(II)/Fe(III) redox-coupled uranium extraction can efficiently reduce the cell voltage of electrochemical uranium extraction (EUE). How to regulate the surface structure to enhance the uranium acyl ion adsorption capacity and strengthen the Fe(II)/Fe(III) redox cycle process is crucial for EUE. In this work, we developed surface sulfated nanoreduced iron (S-NRI) for EUE and exhibited improved properties for EUE at an ultralow cell voltage (-0.1 V). Compared with a nanoreduced iron (NRI) adsorbent, S-NRI displayed faster electrochemical extraction kinetics properties and higher extraction efficiency and capacity for uranium. In a more complex seawater electrolyte containing uranyl ion concentration ranging from 1 to 20 ppm, the removal efficiency could reach almost ∼100% after EUE for 24 h. At a higher 50 ppm uranium acyl ion concentration in a seawater electrolyte, S-NRI exhibited higher extraction capacity (755.03 mg/g), which is better than 528.53 mg/g of NRI at a cell voltage of -0.1 V. Outstanding EUE property could be attributed to the fact that sulfate species (M-SO42-) on the S-NRI surface not only enhanced selective adsorption of uranyl ions but also strengthened the Fe(II)/Fe(III) redox cycle, which accelerated electron transfer between Fe(II) and U(VI), promoted the regeneration of Fe(II) active sites, and finally enhanced the EUE property.


Assuntos
Compostos Férricos , Urânio , Adsorção , Ferro , Sulfatos , Óxidos de Enxofre , Compostos Ferrosos
2.
Environ Sci Technol ; 57(51): 21908-21916, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38085070

RESUMO

Improving the adsorption selectivity, enhancing the extraction capacity, and ensuring the structural stability of the adsorbent are the key to realize the high efficiency recovery of uranium. In this work, we utilized the strong Lewis acid-base interaction between S2- and U(VI)O22+ coupling rapid electron transfer at the MnS/U(VI)O22+ solid-liquid interface to achieve excellent selectivity, high adsorption capacity, and rapid extraction of uranium. The as-synthesized MnS adsorbent exhibited an ultrahigh uranium extraction capacity (2457.05 mg g-1) and a rapid rate constant (K = 9.11 × 10-4 g h-1 mg-1) in seawater with 100.7 ppm of UO2(NO3)2 electrolyte. The kinetic simulation reveals that this adsorption process is a chemical adsorption process and conforms to a pseudo-second-order kinetic model, indicating electron transfer at the MnS/U(VI)O22+ solid-liquid interface. The relevant (quasi) in situ spectroscopic characterization and theoretical calculation results further revealed that the outstanding uranium extraction property of MnS could be attributed to the highly selective UO22+ adsorption of MnS with lower adsorption energy as a result of the strong interaction between S2- and UO22+ and the rapid mass transfer and interface electron transfer from S2- and low-valent Mn(II) to U(VI)O22+.


Assuntos
Urânio , Urânio/química , Elétrons , Transporte de Elétrons , Enxofre , Adsorção , Água do Mar
3.
J Environ Sci Health B ; 58(2): 131-138, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36727586

RESUMO

Agrilus planipennis Fairmaire is an important wood boring pest of Fraxinus species in the family Oleaceae. Oxacyclotridecan-2-one is an attractant of A. planipennis. Traps with attractive lures can be used in mass trapping of insect pests, but the traps are a bit expensive and they must be set up and dismantled in the field. To develop an attract and kill method for A. planipennis, we enveloped oxacyclotridecan-2-one into sustained-released microspheres. The attractant microspheres were prepared using the solvent evaporation method. An orthogonal test L16(45) was used to optimize the five preparation factors: the quantities of polylactic acid (PLA), gelatin, Polyvinyl alcohol (PVA), attractant, and the rotational speed. The results showed that optimal conditions for preparation of microspheres were 2.5 g PLA, 0.5 g gelatin, 1.25 g PVA, 2 mL attractant and 600 r min-1 rotational speed. The encapsulation efficiency of the prepared microspheres was 95.22%, and the attractant loading rate was 15.61%. The release rate of attractant from prepared microspheres was about 26.74% on the first day, and then gradually entered a sustained-release stage for about 10 days that lasted for 17 days. Preliminary field control experiments showed that the prepared microspheres could attract and kill A. planipennis adults when sprayed together with insecticide.


Assuntos
Besouros , Inseticidas , Animais , Larva , Gelatina , Microesferas , Inseticidas/farmacologia
4.
Angew Chem Int Ed Engl ; 62(21): e202217601, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36905159

RESUMO

Nano-reduced iron (NRI) is a promising uranium adsorbent due to its strong reducibility and good selectivity, but it still faces the challenges of slow kinetics, limited and non-renewable active sites. In this work, we realized high efficiency uranium extraction under ultra-low cell voltage (-0.1 V) in seawater with 20 ppm UO2 (NO3 )2 solution by coupling electrochemical mediated FeII /FeIII redox and uranium extraction. The adsorption capacity and extraction efficiency of NRI after electrochemical uranium extraction (EUE) could reach 452 mg/g and 99.1 %, respectively. Combined with quasi-operando/operando characterization technologies, we clarified the mechanism of EUE and revealed that continuously regenerating FeII active sites by electroreduction could significantly enhance the property of EUE. This work here provides a new electrochemical mediated and low energy consumption uranium extraction strategy which also provides a reference for other metal resource recovery.

5.
Bull Entomol Res ; 111(2): 146-152, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32677606

RESUMO

Aggressive behaviour is common in animals and typically has lifetime consequences. As younger males have higher residual reproductive value than older males and lose more from injuries than older males do, the propensity for fighting tends to increase with age in many empirical reports and species. However, fighting patterns in those empirical reports cannot confirm the hypothesis that individuals cannot readily inflict injuries on their opponents. To address this shortcoming, a parasitoid wasp species, Anastatus disparis (Hymenoptera: Eupelmidae), was used as an experimental model to explore the characteristics of aggression from a life-history perspective; this wasp exhibits extreme fighting, resulting in contestants experiencing injury and death. Results showed that the energetic costs of fighting to injury significantly shortened life and caused the loss of most mating ability. Inconsistent with general predictions, the frequency and intensity of fighting in A. disparis significantly decreased with male age. Further study results showed significantly more young males were received by and successfully mated with virgin females, and most genes related to energy metabolism were downregulated in aged males. Our study provided supporting evidence that young A. disparis males show more aggression likely because of their resource holding potential and sexual attractiveness decline with age.


Assuntos
Agressão/fisiologia , Vespas/fisiologia , Fatores Etários , Animais , Metabolismo Energético/fisiologia , Feminino , Características de História de Vida , Masculino , Modelos Animais , Reprodução/fisiologia , Comportamento Sexual Animal
6.
BMC Genomics ; 21(1): 492, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32682391

RESUMO

BACKGROUND: Differences in the expression of genes present in both sexes are assumed to contribute to sex differences including behavioural, physiological and morphological dimorphisms. For enriching our knowledge of gender differences in an important egg parasitoid wasp, Anastatus disparis (Hymenoptera: Eupelmidae), sex-biased differences in gene expression were investigated using Illumina-based transcriptomic analysis. RESULTS: A total of 15,812 resulting unigenes were annotated, and a large set of genes accounting for 50.09% of the total showed sex-biased expression and included 630 sex-specific genes. Gene Ontology (GO) enrichment analyses showed that the functional categories associated with sex-biased genes were mainly related to reproduction. In addition, the transcriptome data provided evidence that sex pheromones in A. disparis are produced by the female, and activity of Δ12-desaturases appear to have been replaced by Δ9-desaturases playing roles in sex pheromone production. The large set of sex-biased genes identified in this study provide a molecular background for sexually dimorphic traits such as flyability, longevity, and aggression in this species and suggests candidate venom proteins expressed only in females that could be used for biological control. CONCLUSIONS: This study provides comprehensive insight into sexually dimorphic traits of a parasitoid wasp and can inform future research into the molecular mechanisms underlying such traits and the application of parasitoids to the biological control of pest species.


Assuntos
Vespas/genética , Agressão , Animais , Feminino , Voo Animal , Perfilação da Expressão Gênica , Longevidade/genética , Masculino , Caracteres Sexuais , Transcriptoma , Vespas/fisiologia
7.
J Chem Ecol ; 46(7): 567-580, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32676764

RESUMO

Two odorant receptors (ORs), OnubOR3 and OnubOR6, in the sex pheromone communication systems of E- and Z-strain European corn borers, Ostrinia nubilalis, were broadly receptive to analogs of their pheromone components. In addition to responding to their natural 14-carbon pheromone components, (Z)-11- and (E)-11-tetradecenyl acetates (Z11- and E11-14:OAc), these pheromone ORs responded to the longer-chain compounds, (Z)-11- and (E)-11-hexadecenyl acetate (Z11- and E11-16:OAc). Z11-16:OAc is a pheromone gland constituent of E-strain O. nubilalis females in Europe but has not previously been shown to have behavioral activity to males. Here, we demonstrate that Z11-16:OAc evokes high levels of upwind flight and source location in E-strain males when substituted for Z11-14:OAc (minor component) in the E-strain blend. Since Z11-16:OAc is found in the gland and has behavioral activity when Z11-14:OAc is missing, then it should be classified as a cryptic, redundant minor pheromone component in E-strain O. nubilalis. The opposite geometric isomer, E11-16:OAc, also functions in Z-strain O. nubilalis, substituting behaviorally for the E11-14:OAc minor component, but has not been found in Z-strain female glands. Single-sensillum recordings showed that sensory neurons of E- and Z-strain male antennae expressing OnubOR3 and OnubOR6 produced responses to these hexadecenyl acetates similar to those evoked by the natural (tetradecenyl acetate) pheromone components. We postulate that the wide responsiveness of these two ORs to the 16-carbon acetates could be a preadaptation for O. nubilalis to use these compounds as minor components in lieu of the respective 14-carbon acetates. Alternatively, the responsiveness of OnubOR3 to E11-16:OAc and OnubOR6 to Z11-16:OAc could represent a vestigial state of these receptors, with the 16-carbon acetates having previously acted as functional minor components in an ancestral blend.


Assuntos
Quimiotaxia , Mariposas/fisiologia , Receptores Odorantes/fisiologia , Atrativos Sexuais/fisiologia , Acetatos/metabolismo , Animais , Ácidos Graxos Monoinsaturados/metabolismo , Masculino , Especificidade da Espécie
8.
J Insect Sci ; 20(3)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32458992

RESUMO

Aggressive behavior is widely observed in animal species for acquiring important resources and usually includes both dangerous and nondangerous fighting patterns. Only a few species show dangerous fighting patterns that are defined by fights ending with contestants being severely injured or killed. Prior experience, an important factor in many species, has been demonstrated to affect a contestant's subsequent fighting behavior. Few studies have focused on the effect of experience on aggression involving dangerous fighting patterns. Here, an egg parasitoid wasp, Anastatus disparis, which shows extreme and dangerous fighting behavior to acquire mating opportunities, was used as an experimental model. Our results showed that the fighting intensity of the winning males significantly decreased subsequent fighting behavior, which was inconsistent with general predictions. Transcriptomic analyses showed that many genes related to energy metabolism were downregulated in winners, and winners increased their fighting intensity after dietary supplementation. Our study suggested that fighting in A. disparis is a tremendous drain on energy. Thus, although males won at combat, significant reductions in available energy constrained the intensity of subsequent fights and influenced strategic decisions. In addition, winners might improve their fighting skills and abilities from previous contests, and their fighting intensity after dietary supplementation was significantly higher than that of males without any fighting experience. Generally, in A. disparis, although winners increased their fighting ability with previous experience, the available energy in winners was likely to be a crucial factor affecting the intensity and strategic decisions in subsequent fights.


Assuntos
Comportamento Sexual Animal , Vespas/fisiologia , Agressão , Animais , Comportamento Animal , Acontecimentos que Mudam a Vida , Masculino
9.
Genome ; 62(10): 689-703, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31315001

RESUMO

Sea buckthorn (Hippophae rhamnoides L.) is a plant with economic and ecological value. It is uniquely capable of growing well under salt and drought stress. WRKY transcription factors play important roles in the ability of plants to resist stress. In this study, 48 HrWRKY genes were identified based on RNA sequencing of H. rhamnoides. Evaluation of expression pattern of HrWRKY1, HrWRKY17, HrWRKY18, HrWRKY21, HrWRKY33-2, HrWRKY40-2, HrWRKY41, and HrWRKY71 suggested that they were involved in abiotic stress. Interestingly, HrWRKY21, one of eight HrWRKY genes, was a positive regulator of abiotic stress tolerance in H. rhamnoides. In addition, most morphological attributes of roots in transgenic Nicotiana tabacum lines (overexpressing HrWRKY21) were also markedly increased compared with the wild-type (WT), including total lengths, specific root lengths, and surface areas. Stress tolerance of transgenic lines was also correlated with higher antioxidant activity (SOD and POD), lower percentage of relative conductivity (REC), and lower activity of malondialdehyde (MDA) under stress conditions. These findings represent a foundation of knowledge about the molecular mechanisms driving resistance to adverse conditions in plants; they are a promising step towards development of tree cultivars with improved tolerance to abiotic stress.


Assuntos
Genes de Plantas , Hippophae/genética , Família Multigênica , Estresse Fisiológico/genética , Germinação/genética , Hippophae/fisiologia , Filogenia , Plantas Geneticamente Modificadas , Frações Subcelulares/metabolismo , Nicotiana/genética
10.
J Chem Ecol ; 44(7-8): 637-649, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29956046

RESUMO

We performed single-sensillum recordings from male and female antennae of the Asian longhorned beetle, Anoplophora glabripennis, that included as stimuli the two components of this species' aggregation-sex pheromone in addition to various general odorants. We compared the aggregation-sex-pheromone-component responses of olfactory sensory neurons (OSNs) to those of OSNs that responded to a variety of plant-related odorants. In the smooth-tipped, tapered, trichoid sensilla on the most distal antennal flagellomeres nos. 10 or 11 of both males and females, we found OSNs with high-amplitude action potentials that were tuned to the aldehyde and alcohol pheromone components and that did not respond to various plant-related volatiles. Because this OSN type responded to both the alcohol and aldehyde components it cannot be considered to be specifically tuned to either component. These large-spiking OSNs were co-compartmentalized in these sensilla with a second, smaller-spiking OSN responding to plant-related volatiles such as geraniol, citronellal, limonene, 1-octanol, nerol and citral. The large-spiking OSNs thus appear to be a type that will be involved in aggregation-sex pheromone pathways targeting a specific glomerulus in the antennal lobe and in generating pheromone-related behavioral responses in A. glabripennis. In other sensilla located in these distal antennal flagellomeres as well as those located more proximally, i.e., mid-length along the antenna on flagellomere nos. 4-7, we found OSNs in blunt-tipped basiconic sensilla that were responsive to other plant-related volatiles, especially the terpenoids, (E,E)-alpha farnesene, (E)-ß-farnesene, ß-caryophyllene, and eugenol. Some of these terpenoids have been implicated in improving attraction to pheromone-baited traps. Some of these same OSNs responded additionally to either of the two sex pheromone components, but because these OSNs also responded to some of the above plant volatiles as shown by cross-adaptation experiments, these OSNs will not be the types that convey sex-pheromone-specific information to the antennal lobe.


Assuntos
Besouros/fisiologia , Neurônios Receptores Olfatórios/fisiologia , Sensilas/fisiologia , Atrativos Sexuais/metabolismo , Potenciais de Ação , Animais , Besouros/citologia , Feminino , Masculino , Neurônios Receptores Olfatórios/citologia , Plantas/química , Plantas/metabolismo , Sensilas/citologia , Atrativos Sexuais/química , Comportamento Sexual Animal , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
11.
Wei Sheng Yan Jiu ; 45(5): 795-806, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29903134

RESUMO

OBJECTIVE: To study the characteristics of indoor/outdoor organic and elemental carbon in the PM_(2. 5). METHODS: Seven type regions were selected in Beijing. The samples of OC and EC in PM_(2. 5)were collected and were measured in the indoor /outdoor of seven type areas respectively from May 2013 to April 2014. RESULTS: The overall concentrations( median and P25-P75) of indoor OC and EC in PM_(2. 5)were 13. 4 µg /m~3( 8. 82- 26. 6 µg/m~3) and 3. 79 µg /m~3( 2. 09-6. 98 µg /m~3), and the concentrations of outdoor OC and EC were 15. 4 µg / m~3( 10. 6- 35. 2 µg /m~3) and 4. 96 µg/m~3( 2. 92-9. 39 µg/m~3), respectively. Indoor and outdoor OC were the dominant species occupying78% and 73% of TC, respectively. Outdoor carbonaceous matter was higher than indoor matter and the concentration of OC was higher than that of EC. The outdoor OC concentration during heating period was the highest in all seasons and the concentrations ofother seasons found no difference. The outdoor OC concentration in weekend was high, while was lower during the period of Monday to Wednesday. The outdoor OC concentrations of seven type areas were different and the pollutants from dust area, aviation fuel emissions, industry and light industry were highest, followed by ones from vehicle emissions, coal-burning power plant, and one in clean district was the lowest. There were high linear relationships between outdoor OC and outdoor EC( r = 0. 886), between indoor OC and outdoor OC( r = 0. 915), between indoor EC and outdoor EC( r =0. 894), between carbonaceous matter and PM_(2. 5)( rOC-PM_(2. 5)= 0. 785, rEC-PM 2. 5= 0. 775), respectively. The indoor OC to outdoor OC ratio in summer was the highest in all seasons and the ratios of other seasons found no difference. The outdoor OC to outdoor EC ratio in heating period was highest, and was lowest in summer. CONCLUSION: We should pay attention to OC and EC pollution in Beijing air, should strengthen the protection to OC pollutants during the haze, and should take some measures to control the pollution of OC.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Carbono/análise , Monitoramento Ambiental , Tamanho da Partícula , Aerossóis , Pequim , Humanos , Material Particulado , Estações do Ano
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(3): 395-9, 2015 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-26080865

RESUMO

OBJECTIVE: To compare the differences of children's health in different area, and to confirm if the prevalence of respiratory diseases and symptoms among children are closely associated with the air pollution. METHODS: A cross-sectional study was conducted in an urban area A and a suburban area B with different levels of air pollution in Beijing. Using a cluster sampling method, we recruited 4 564 children from 3 primary schools in urban A and 4 primary schools in suburban B. Respiratory symptoms were investigated using an international standardized questionnaire including characteristics of children, living conditions, respiratory diseases and symptoms and situation of parents. The concentrations of air pollutants for recent five years were obtained from Reports on the Quality of the Beijing Environment. SPSS 16.0 was used to analyze data. RESULTS: The prevalence of cough, persistent cough, phlegm, persistent phlegm, wheeze and asthma in A area were higher than those in B area [(62.2% vs. 59.9%), (6.3% vs. 3.1%), (42.4% vs. 37.4%),(3.6% vs. 2.4%),(13.3% vs. 9.9%)and(9.5% vs. 5.4%)]. Except for cough, cough with cold, cough without cold, the prevalence of respiratory diseases and symptoms in A area were significantly higher than those in B area (P<0.05). Logistic regression analysis showed the prevalence of persistent cough, phlegm without cold, asthma in A area were significantly higher than those in B area (P<0.05). CONCLUSION: Respiratory diseases and symptoms among school-age children were closely associated with the level of air pollution.


Assuntos
Poluição do Ar/análise , Meio Ambiente , Doenças Respiratórias/epidemiologia , População Suburbana , População Urbana , Asma/epidemiologia , Criança , China , Cidades , Tosse/epidemiologia , Estudos Transversais , Humanos , Prevalência , Sons Respiratórios , Inquéritos e Questionários
13.
Plant Physiol Biochem ; 214: 108944, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39033651

RESUMO

Anoplophora glabripennis (ALB) is one of the most devastating wood boring insects of poplars. Populus deltoides 'Shalinyang (PdS), a new poplar variety, shows strong resistance to ALB infestation. However, the molecular mechanism of insect resistance in PdS is unclear. Here, we found that lignan content was much higher in PdS phloem after ALB infestation than in healthy trees, and that adding lignan to artificial diet significantly reduced: larval weight; digestive enzyme activity (cellulase [CL], polygalacturonase [PG]); detoxification enzyme activity (carboxylesterase [CarE], glutathione S-transferase [GSH-ST]); and defense enzyme activity (Catalase [CAT]). We further identified the lignan biosynthesis-related PdPLR1 gene (Pinoresinol-lariciresinol reductase, PLR) based on transcriptome analysis, and it was significantly up-regulated in the PdS phloem attacked by ALB. Overexpression of PdPLR1 in Arabidopsis increased th lignan content. In contrast, silencing PdPLR1 in PdS significantly decreased expression levels of PdPLR1 and lignan content by 82.45% and 56.85%. However, silencing PdPLR1 increased the number of adults ovipositions and eggs hatching. The activity of CL, PG, CarE, GSH-ST and CAT and the biomass of larvae fed on phloem of PdS with silenced PdPLR1 were significantly higher than in the control. Taken together, up regulation of PdPLR1 enhanced PdS resistance to ALB by regulating lignan synthesis. Our findings provide in-depth insights into the molecular mechanisms of PdS-ALB interactions, which lay the foundation for understanding of defense in poplars to pest infection.


Assuntos
Lignanas , Proteínas de Plantas , Populus , Lignanas/biossíntese , Lignanas/metabolismo , Populus/genética , Populus/metabolismo , Animais , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Larva , Plantas Geneticamente Modificadas , Besouros/metabolismo
14.
J Insect Sci ; 13: 59, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23906184

RESUMO

Anopiophora glabripennis (Motsch.) (Coleoptera: Cerambycidae) is a destructive woodborer, attacking many species of deciduous hardwood trees. Apriona swainsoni (Hope) (Coleoptera: Cerambycidae) is a woodborer of Sophora japonica L. (Angiospermae: Fabaceae). Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is an important natural enemy of both Cerambycid species in China. Kairomones for two populations of D. helophoroides that parasitize A. glabripennis and A. swainsoni respectively were studied. Based on identification and quantification of volatiles from larval frass produced by A. glabripennis and A. swainsoni, monoterpenes were selected to test their kairomonal activity to both populations of D. helophoroides adults using a Y-tube olfactometer. The results indicated that (S)-(-)-limonene served as a kairomone for the population of D. helophoroides parasitized A. glabripennis. α-pinene, (IR)-(+)-αpinene and (+)-ß-pinene were attractive to the population of D. helophoroides parasitized A. swainsoni. The results provide information about the co-evolution of D. helophoroides, its host, and host-food trees.


Assuntos
Besouros/fisiologia , Fezes/química , Interações Hospedeiro-Parasita , Monoterpenos/análise , Sophora , Animais , Evolução Biológica , Besouros/parasitologia , Sinais (Psicologia) , Herbivoria , Larva/parasitologia , Larva/fisiologia , Olfato , Estereoisomerismo
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(9): 832-6, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24351565

RESUMO

OBJECTIVE: To study the concentration level and characteristics of indoor particle matter ≤ 2.5 µm in aerodynamic diameter (PM2.5) under extreme weather condition. METHODS: During the period of haze in January 2013 and the fireworks and firecracker setting off in the Spring Festival of February 2013, three monitoring sites located indoor and outdoor were respectively selected by Beijing CDC, considering the vertical and horizontal distance, windows tightness and human activity indoor. PM2.5 samples were collected by filters and measured by laboratory weight method. At the same time, the meteorological data was also collected. RESULTS: The median (quartiles) of overall concentration level of indoor PM2.5 was 87.76 µg/m(3) (52.05-174.48 µg/m(3)) and was lower than that of outdoor PM2.5 (128.79 µg/m(3), 95.14-221.88 µg/m(3); Z = -4.13, P < 0.01). The concentration of three indoor monitoring sites was different (χ(2) = 23.09, P < 0.01). The PM2.5 concentrations of monitoring point B in poor sealing window was the highest (94.05 µg/m(3); 63.46-189.17 µg/m(3)) and point C in sealed and less human activity, which was the lowest (77.89 µg/m(3), 51.19-144.40 µg/m(3)). The concentration level of indoor PM2.5 in the haze period (273.22 µg/m(3), 223.44-308.47 µg/m(3)) was higher than the overall concentration level of indoor PM2.5 (Z = -5.20, P < 0.01). The concentration level of indoor PM2.5 in the fireworks and firecracker period (167.90 µg/m(3), 129.15-187.90 µg/m(3)) was higher than that in the Spring Festival period (7 days, 72.76 µg/m(3), 36.97-145.30 µg/m(3), Z = -2.34, P < 0.05) and the overall concentration level of indoor PM2.5 (Z = -1.98, P < 0.05); however, it was lower than the concentration level of indoor PM2.5 in the haze period (Z = -3.43, P < 0.01). The I/O ratio (indoor concentration/outdoor concentration) was all less than 1.00 except 4, which was between 1.00-1.09. The mean I/O ratio in monitoring site B, monitoring site A and monitoring site C was 0.69 ± 0.21, 0.64 ± 0.23 and 0.58 ± 0.18, respectively, show significant bias (F = 22.85, P < 0.01). During the period of haze, the fireworks and firecracker and fine weather (when ambient PM2.5 concentration was lower than the standard value of 75 µg/m(3)), the mean I/O ratio was 0.87 ± 0.14, 0.68 ± 0.08 and 0.51 ± 0.18, respectively, showing significant bias (F = 29.88, P < 0.05). Under conditions of snow and high wind speed ( ≥ 3.4 m/s), PM2.5 concentration decreased to the valley point. The valley value of I/O ratio only occurred after several days of high windy weather. Moreover, the PM2.5 concentration level of indoor air showed a delayed 1-2 days after the haze weakened or disappeared. CONCLUSION: Mass concentration of indoor PM2.5 increased significantly with increases of outdoor concentration. Haze and setting off fireworks/firecracker could lead to a serious decline of indoor air quality (IAQ), and the improvement of IAQ was lagging behind the outdoor changes.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Estações do Ano , China , Monitoramento Ambiental , Tamanho da Partícula
16.
Pest Manag Sci ; 79(10): 3538-3547, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37160852

RESUMO

BACKGROUND: The Asian longhorned beetle (ALB), Anoplophora glabripennis, is a serious wood borer of hardwood trees. Populus deltoides 'Shalinyang' (PdS) is attractive to ALB adults for oviposition but highly resistant to their offspring. Investigation of the chemicals regulating ALB oviposition is scarce in previous studies until now. To determine which chemicals emitted by PdS were attractive and induced oviposition behavior by ALB on non-host poplar tree species, we first: collected and identified the bio-active volatiles produced by PdS using coupled gas chromatography-mass spectrometry (GC-MS) and coupled gas chromatography-electroantennographic detector (GC-EAD); then evaluated which chemicals were attractive in a Y-tube olfactometer bioassay; and finally screened key compounds affecting ALB oviposition using a 'chemical-stimulated oviposition on non-host tree' bioassay. RESULTS: (E)-2-Hexenal, hexyl acetate, (Z)-3-hexenol acetate, 1-hexanol, (Z)-3-hexenol, ß-caryophyllene, and salicylaldehyde emitted from PdS were attractive to ALB. When (E)-2-hexenal, 1-hexanol, (Z)-3-hexenol acetate, and (Z)-3-hexenol were applied to the non-host tree Populus tomentosa, oviposition by ALB females was significantly increased. Furthermore, the mean number of oviposition pits increased as the (Z)-3-hexenol concentrations increased. Further tests on synergy between pairs of chemicals showed that (Z)-3-hexenol stimulated production of the most oviposition pits, but that the percentage of effective oviposition pits (those containing an egg and larva and not empty) decreased. CONCLUSION: (Z)-3-Hexenol is the main chemical component inducing ALB oviposition. These results increase understanding about the oviposition behavior of ALB and could help improve management strategies that regulate ALB behavior by planting mixed-species forests resistant to ALB. © 2023 Society of Chemical Industry.


Assuntos
Besouros , Árvores , Animais , Feminino , Oviposição , Cromatografia Gasosa-Espectrometria de Massas
17.
Pest Manag Sci ; 79(11): 4172-4185, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37318769

RESUMO

BACKGROUND: Terpenoids emitted from plants are important for regulating plant-insect interaction. However, it is still unclear how terpenoids affect the host defense system. There are few reports of terpenoids' involvement in the mechanisms that regulate woody plants' insect resistance. RESULTS: The (E)-ß-ocimene of terpenes was only found in RBO-resist leaves, and its content was higher than that of other type terpenes. Further, we also found (E)-ß-ocimene had a significant avoidance effect on RBO and reached 87.5% of the highest avoidance rate. Meanwhile, overexpression of HrTPS12 in Arabidopsis increased the HrTPS12 expression level, (E)-ß-ocimene content, and enhanced the defense against RBO. However, silencing HrTPS12 in sea buckthorn revealed that the expression levels of HrTPS12 and (E)-ß-ocimene significantly decreased, causing the attraction effect on RBO. CONCLUSION: HrTPS12 was an up-regulator, which improves sea buckthorn resistance to RBO by regulating the synthesis of volatile (E)-ß-ocimene. These results provide in-depth information about the interaction between RBO and sea buckthorn and provide a theoretical basis for developing plant-based insect repellents that can be used to manage RBO. © 2023 Society of Chemical Industry.

18.
Wei Sheng Yan Jiu ; 41(5): 805-8, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23213698

RESUMO

OBJECTIVE: To investigate the exposure level of 16 metal elements (Pb, Cd, Cu, Zn, Fe, Mn, Ni, Ag, Sb, Se, Al, Ba, Be,T1, Mo and Na) in drinking water for residents in Beijing. METHODS: To monitor 16 elements in drinking water collected by multi-stage cluster sampling method from 270 families in summer and winter and detected by inductively coupled plasma mass spectrometry. The data were analyzed by SPSS 17.0 COMPLEX SAMPLE. RESULTS: The exposure levels from low to high can be divided into three layers. The exposure level for Ag, Cd, Sb, Be and T1 was from not detected to 0.083 microg/L, for Mo,Pb, Ni and Se was 0.06-100 microg/L, for Cu,Al,Zn,Mn,Fe,Na and Ba was 0. 00036-6. 579mg/L. The exposure level of 11 elements ( Pb, Se, Mo, Cu, Zn, Mn, Ni, Al, Ba, Fe, Na) in summer was higher than that in winter. The qualified rate for Na, Al, Mn, Zn, Fe, Ba, Pb and Se was 95.6%, 98.9%, 93.3%, 95.9%, 87.4%, 96.7%, 98.1% and 93.7% in winter respectively. The qualified rate for Mn, Ni, Zn, Fe, Pb and Se was 95.9%, 99.6%, 95.2%, 98.1%, 96.7%, 98.1% in summer respectively. The qualified rate for other elements was 100%. CONCLUSION: The qualification of 16 metal elements in drinking water in Beijing were in low exposure levels. Most of indicators in municipal water supply were better than those in self-provided water supply.


Assuntos
Água Potável/análise , Monitoramento Ambiental/métodos , Metais/análise , Poluentes da Água/análise , Cádmio/análise , China , Cobre/análise , Exposição Ambiental/análise , Humanos , Chumbo/análise , Estudos de Amostragem
19.
Wei Sheng Yan Jiu ; 41(5): 809-13, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23213699

RESUMO

OBJECTIVE: To investigate the influencing factors for daily water intake of Beijing residents. METHODS: A multi-stage sampling method was constructed to interview 270 Beijing residents in the winter of 2009 and in the summer of 2010 by using a questionnaire to collect data on daily drinking water consumption. Multilevel models were used to analyze the variation and influencing factors for the amount of water intake. RESULTS: Multilevel model results showed that the average daily water intake of residents living in different villages or neighborhood committees was statistically significant (sigma2 mu0 = = 0.030 (0.009), P < 0.05). The individual variation in the same village or neighborhood committee was also significant (sigma2 e0 = 0.157 (0.010), P < 0.05). Season, gender, and body weight affected the daily water intake (P < 0.05). There were interaction between season and source of water supply. CONCLUSION: The average daily water intake of residents was affected by several factors. In the health risk assessment of drinking water, it needs considering not only the individual characteristics but also the differences of villages/neighborhood committees and the seasonal variation.


Assuntos
Água Potável/administração & dosagem , Ingestão de Líquidos , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multinível , Estudos de Amostragem , Inquéritos e Questionários
20.
Zhong Yao Cai ; 35(10): 1557-61, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23627117

RESUMO

OBJECTIVE: To explore the relation between the quality of the Herb-Paris and their cultivation of soil nutritional status. METHODS: The soil nutrient status (0 - 30 cm) of Paris polyphylla var. yunnanensis, artificially cultivated areas were determined in 2009 and their rhizome qualities harvested in 2010 were evaluated respectively. Determination of 0 - 30cm depth soil ingredients status with soil conventional five nutritional analysis method of 29 artificial cultivation area, 9 Prefectures of Yunnan Province. RESULTS: Soil nutrient has effect on quality of Herb-Paris medicinal ingredients. CONCLUSION: The multiple linear stepwise regression analysis reveals that among a certain range, the steroidal saponin VII content is positively correlated with the content of soil organic matter and pH. Steroidal saponin H content is positively correlated with the content of soil organic matter, available P and pH. Steroidal saponin I is positively correlated with the content of available K, but negatively correlated with the content of available Herb-Paris, and steroidal saponin II is positively correlated with the content of soil organic matter and available K.


Assuntos
Liliaceae/química , Nitrogênio , Rizoma/química , Saponinas/análise , Solo/análise , Agricultura/métodos , China , Cromatografia Líquida de Alta Pressão , Fertilizantes , Concentração de Íons de Hidrogênio , Liliaceae/crescimento & desenvolvimento , Fósforo , Potássio , Controle de Qualidade , Análise de Regressão , Rizoma/crescimento & desenvolvimento , Solo/química
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