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Extracting rare earth elements (REEs) from wastewater is essential for the growth and an eco-friendly sustainable economy. However, it is a daunting challenge to separate individual rare earth elements by their subtle differences. To overcome this difficulty, we report a unique REE nanotrap that features dense uncoordinated carboxyl groups and triazole N atoms in a two-fold interpenetrated metal-organic framework (named NCU-1). Notably, the synergistic effect of suitable pore sizes and REE nanotraps in NCU-1 is highly responsive to the size variation of rare-earth ions and shows high selectivity toward light REE. As a proof of concept, Pr/Lu and Nd/Er are used as binary models, which give a high separation factor of SFPr/Lu = 796 and SFNd/Er = 273, demonstrating highly efficient separation over a single step. This ability achieves efficient and selective extraction and separation of REEs from mine tailings, establishing this platform as an important advance for sustainable obtaining high-purity REEs.
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Effective and selective removal of 99TcO4-, one of the most nuisance radionuclides in nuclear waste, is highly desirable but remains a significant challenge. Herein, two isostructural MOFs, NCU-3-X (X = Cl, Br) were constructed by ZnX2 coordinated to nitrogen-containing neutral ligand tri(4-(1H-imidazole-1-l) phenyl) amine for efficient adsorption ReO4-/TcO4-. Owning to the twofold interpenetrating structure, both of them exhibit strong alkaline resistance. Consequently, NCU-3-Br exhibited superior adsorption performances with a maximum capacity as high as 483 mg/g, which is 2.23 times larger than that of NCU-3-Cl. The primary reasons accounting for the enhanced adsorption performances of NCU-3-Br are that compared to chlorine atoms, the smaller electronegativity of bromine atoms as halogen bonds donor can facilitate the formation of σ-holes, enhance positively charged skeleton, and reduce the adsorption energy associated with ReO4-/TcO4-. In addition, the one-dimensional hydrophobic channels in the NCU-3-Br framework enable NCU-3-Br to have highly selective toward ReO4-, which has a low relative charge density against interfering ions. The SRS simulation removal experiment further confirmed the excellent adsorption capacity of NCU-3-Br to ReO4-/TcO4-. This work illustrated that the halogenated new strategy incorporated different halogen atoms into MOF skeletons can dramatically modulate the adsorption performances for ReO4-/TcO4-.
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Rationally designed new materials for the selective detection and adsorption of 99Tc, a problematic element in nuclear waste, are important and challenging in environmental monitoring. Here, we utilize an interpenetration approach to develop a cationic fluorescent metal-organic framework (NCU-2), which was constructed by a flexible tridentate nitrogen-containing ligand and Ag+ metal ions. The NCU-2 is a scarce case of 14-fold interpenetrated with excellent chemical stability even under 0.5 M HNO3, which is helpful for the detection and removal of ReO4-/TcO4- from nuclear waste. Excitingly, the fluorescence signal of NCU-2 was obviously quenched in the presence of ReO4- (a nonradioactive surrogate of TcO4-) due to the robust interaction between ReO4- and the host for the formation of a non-fluorescent complex. Furthermore, the NCU-2 exhibits a high selectivity sensing of ReO4- in the presence of excess competitive ions. The superior response of NCU-2 toward ReO4- is ascribed to the high-fold structure and the luxuriant unsaturated Ag metal sites on the wall of 1D pore channels, which can enhance the framework positive charge and accelerate the transport of guest molecules to strengthen the interaction between them. Notably, NCU-2 successfully quantified trace levels of ReO4- in simulated Hanford waste with a broad linear range (0.2-200 µM) and a low detection limit of 66.7 nM. Moreover, NCU-2 also shows a high adsorption capacity to ReO4- (541 mg/g) and rapid sorption kinetics, making it extremely attractive for waste monitoring and emergency remediation.
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Estructuras Metalorgánicas , Residuos Radiactivos , Adsorción , Cationes , MetalesRESUMEN
99Tc is one of the most problematic nuclear fuel products due to its long half-life and high environmental mobility. Direct removal of TcO4- from the highly alkaline solution of nuclear fuel is a serious and challenging environmental issue. In this work, the first efficient synthetic approach introducing halogens into a two-dimensional metal-organic framework, named Mn-MOF, is established using MnCl2·4H2O coordinating with neutral nitrogen-donor ligand, showing ultrahigh stability in alkaline aqueous even under 1 M NaOH. The luxuriant Mn-Cl bonds and ordered hydrophobic pore channels enable the Mn-MOF to have an efficient adsorption capacity for ReO4- with a large capacity (403 mg g-1), which is higher than most MOF adsorbents. More importantly, the Mn-MOF shows an excellent selectivity toward ReO4- in high-density competitive anions, such as NO3- and SO42-. Moreover, the outstanding performance of Mn-MOF in removing ReO4- endowed it successfully separated ReO4- from the simulated Savannah River Site (SRS) high-level waste (HLW) stream with high removal of 66.84% at the phase ratio of 10. The adsorption mechanism is further demonstrated by FT-IR, XPS analysis, and DFT calculation, showing that the ReO4- can selectively interact with Mn-Cl bonds and imidazole groups, forming unique halogen bonds Cl-O-Re, and a series of hydrogen bonds, respectively. This work suggests a new approach to the removal of TcO4- from nuclear fuel.
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Estructuras Metalorgánicas , Halógenos , Álcalis , Espectroscopía Infrarroja por Transformada de Fourier , AnionesRESUMEN
Background: Iron ions affect the expression of outer membrane protein A (OmpA), a major pathogenic protein in Acinetobacter baumannii. Objective: To analyze the effect of iron ions on the expression of the OmpA protein of A. baumannii and explore its association with the virulence of OmpA. Methods: Site-directed mutagenesis was used to construct ompA gene deletion strains and gene repair strains. The OmpA protein expression of A. baumannii under culture with different contents of iron ions was detected. The virulence of A. baumannii with different OmpA protein expression levels were evaluated in macrophages and mice. Results: OmpA protein levels of the three strains were enhanced under iron-rich conditions. They were reduced in the presence of the iron-chelating agent 2,2'-bipyridine. A. baumannii wild type and + ompA had a remarkable toxic effect on RAW246.7 macrophages (P < 0.05). In contrast, the ΔompA had a significantly reduced toxic effect on RAW246.7 macrophages (P < 0.05). The levels of the inflammatory factors IL-1ß, IL-6, IL-8, and TNFα in the mice spleen were significantly increased in the + ompA strain treatment group compared with the ΔompA strain group (all P < 0.05). In addition, the levels were higher in the presence of iron ions than in the presence of the chelating agent. Conclusion: Iron-rich conditions increase the OmpA protein expression of A. baumannii. Strains with high OmpA protein expression were more invasive, which may be a key determinant of A. baumannii infection and pathogenicity. Iron control strategies might be used for the management of A. baumannii.
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Cotton Verticillium wilt (VW) is a devastating disease seriously affecting fiber yield and quality, and the most effective and economical prevention measure at present is selection and extension of Gossypium varieties harboring high resistance to VW. However, multiple attempts to improve the VW resistance of the most widely cultivated upland cottons have made little significant progress. The introduction of chromosome segment substitution lines (CSSLs) provide the practical solutions for merging the superior genes related with high yield and wide adaptation from Gossypium hirsutum and VW resistance and the excellent fiber quality from Gossypium barbadense. In this study, 300 CSSLs were chosen from the developed BC5F3:5 CSSLs constructed from CCRI36 (G. hirsutum) and Hai1 (G. barbadense) to conduct quantitative trait locus (QTL) mapping of VW resistance, and a total of 40 QTL relevant to VW disease index (DI) were identified. Phenotypic data were obtained from a 2-year investigation in two fields with two replications per year. All the QTL were distributed on 21 chromosomes, with phenotypic variation of 1.05%-10.52%, and 21 stable QTL were consistent in at least two environments. Based on a meta-analysis, 34 novel QTL were identified, while 6 loci were consistent with previously identified QTL. Meanwhile, 70 QTL hotspot regions were detected, including 44 novel regions. This study concentrates on QTL identification and screening for hotspot regions related with VW in the 300 CSSLs, and the results lay a solid foundation not only for revealing the genetic and molecular mechanisms of VW resistance but also for further fine mapping, gene cloning and molecular designing in breeding programs for resistant cotton varieties.
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Verticillium , Cromosomas de las Plantas/genética , Gossypium/genética , Fenotipo , Fitomejoramiento , Sitios de Carácter CuantitativoRESUMEN
Chromosome segment substitution lines (CSSLs) are ideal materials for identifying genetic effects. In this study, CSSL MBI7561 with excellent fiber quality that was selected from BC4F3:5 of CCRI45 (Gossypium hirsutum) × Hai1 (Gossypium barbadense) was used to construct 3 secondary segregating populations with 2 generations (BC5F2 and BC5F2:3). Eighty-one polymorphic markers related to 33 chromosome introgressive segments on 18 chromosomes were finally screened using 2292 SSR markers which covered the whole tetraploid cotton genome. A total of 129 quantitative trait loci (QTL) associated with fiber quality (103) and yield-related traits (26) were detected on 17 chromosomes, explaining 0.85-30.35% of the phenotypic variation; 39 were stable (30.2%), 53 were common (41.1%), 76 were new (58.9%), and 86 had favorable effects on the related traits. More QTL were distributed in the Dt subgenome than in the At subgenome. Twenty-five stable QTL clusters (with stable or common QTL) were detected on 22 chromosome introgressed segments. Finally, the 6 important chromosome introgressed segments (Seg-A02-1, Seg-A06-1, Seg-A07-2, Seg-A07-3, Seg-D07-3, and Seg-D06-2) were identified as candidate chromosome regions for fiber quality, which should be given more attention in future QTL fine mapping, gene cloning, and marker-assisted selection (MAS) breeding.
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Cromosomas de las Plantas/genética , Gossypium/genética , Sitios de Carácter Cuantitativo/genética , Mapeo Cromosómico/métodos , Fibra de Algodón , Cruzamientos Genéticos , Genoma de Planta/genética , FenotipoRESUMEN
BACKGROUND: Verticillium wilt (VW), also known as "cotton cancer," is one of the most destructive diseases in global cotton production that seriously impacts fiber yield and quality. Despite numerous attempts, little significant progress has been made in improving the VW resistance of upland cotton. The development of chromosome segment substitution lines (CSSLs) from Gossypium hirsutum × G. barbadense has emerged as a means of simultaneously developing new cotton varieties with high-yield, superior fiber, and resistance to VW. RESULTS: In this study, VW-resistant investigations were first conducted in an artificial greenhouse, a natural field, and diseased nursery conditions, resulting in the identification of one stably VW-resistant CSSL, MBI8255, and one VW-susceptible G. hirsutum, CCRI36, which were subsequently subjected to biochemical tests and transcriptome sequencing during V991 infection (0, 1, and 2 days after inoculation). Eighteen root samples with three replications were collected to perform multiple comparisons of enzyme activity and biochemical substance contents. The findings indicated that VW resistance was positively correlated with peroxidase and polyphenol oxidase activity, but negatively correlated with malondialdehyde content. Additionally, RNA sequencing was used for the same root samples, resulting in a total of 77,412 genes, of which 23,180 differentially expressed genes were identified from multiple comparisons between samples. After Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis on the expression profiles identified using Short Time-series Expression Miner, we found that the metabolic process in the biological process, as well as the pathways of phenylpropanoid biosynthesis and plant hormone signal transduction, participated significantly in the response to VW. Gene functional annotation and expression quantity analysis indicated the important roles of the phenylpropanoid metabolic pathway and oxidation-reduction process in response to VW, which also provided plenty of candidate genes related to plant resistance. CONCLUSIONS: This study concentrates on the preliminary response to V991 infection by comparing the VW-resistant CSSL and its VW-susceptible recurrent parent. Not only do our findings facilitate the culturing of new resistant varieties with high yield and superior performance, but they also broaden our understanding of the mechanisms of cotton resistance to VW.
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Cromosomas de las Plantas/genética , Gossypium/genética , Gossypium/microbiología , Transcriptoma/genética , Verticillium/patogenicidad , Regulación de la Expresión Génica de las Plantas/genéticaRESUMEN
BACKGROUND: How to develop new cotton varieties possessing high yield traits of Upland cotton and superior fiber quality traits of Sea Island cotton remains a key task for cotton breeders and researchers. While multiple attempts bring in little significant progresses, the development of Chromosome Segment Substitution Lines (CSSLs) from Gossypium barbadense in G. hirsutum background provided ideal materials for aforementioned breeding purposes in upland cotton improvement. Based on the excellent fiber performance and relatively clear chromosome substitution segments information identified by Simple Sequence Repeat (SSR) markers, two CSSLs, MBI9915 and MBI9749, together with the recurrent parent CCRI36 were chosen to conduct transcriptome sequencing during the development stages of fiber elongation and Secondary Cell Wall (SCW) synthesis (from 10DPA and 28DPA), aiming at revealing the mechanism of fiber development and the potential contribution of chromosome substitution segments from Sea Island cotton to fiber development of Upland cotton. RESULTS: In total, 15 RNA-seq libraries were constructed and sequenced separately, generating 705.433 million clean reads with mean GC content of 45.13% and average Q30 of 90.26%. Through multiple comparisons between libraries, 1801 differentially expressed genes (DEGs) were identified, of which the 902 up-regulated DEGs were mainly involved in cell wall organization and response to oxidative stress and auxin, while the 898 down-regulated ones participated in translation, regulation of transcription, DNA-templated and cytoplasmic translation based on GO annotation and KEGG enrichment analysis. Subsequently, STEM software was performed to explicate the temporal expression pattern of DEGs. Two peroxidases and four flavonoid pathway-related genes were identified in the "oxidation-reduction process", which could play a role in fiber development and quality formation. Finally, the reliability of RNA-seq data was validated by quantitative real-time PCR of randomly selected 20 genes. CONCLUSIONS: The present report focuses on the similarities and differences of transcriptome profiles between the two CSSLs and the recurrent parent CCRI36 and provides novel insights into the molecular mechanism of fiber development, and into further exploration of the feasible contribution of G. barbadense substitution segments to fiber quality formation, which will lay solid foundation for simultaneously improving fiber yield and quality of upland cotton through CSSLs.
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Cromosomas de las Plantas/genética , Fibra de Algodón , Perfilación de la Expresión Génica , Gossypium/crecimiento & desarrollo , Gossypium/genética , Hibridación Genética , Pared Celular/metabolismo , Gossypium/citología , Fenotipo , Reproducibilidad de los ResultadosRESUMEN
Background Atypical choroid plexus papilloma (APP) is a rare, newly introduced entity with intermediate characteristics. To date, few reports have revealed the magnetic resonance (MR) findings. Purpose To analyze the clinicopathological and MR features of APP. Material and Methods The clinicopathological data and preoperative MR images of six patients with pathologically proven APP were retrospectively reviewed. The MR features including tumor location, contour, signal intensity, degree of enhancement, intratumoral cysts, and necrosis; and flow voids, borders, peritumoral edema, and associated hydrocephalus were analyzed. Results The APP were located in the ventricle (n = 4) and cerebellopontine angle (CPA, n = 2). Tumor dissemination along the spinal subarachnoid space was found in one patient. The tumors appeared as milt-lobulated (n = 5) or round mass (n = 1), with slightly heterogeneous signals (n = 5) or mixed signals (n = 1) on T1-weighted and T2-weighted images. Heterogeneous and strong enhancement were found in five cases on contrast-enhanced images. Three of four intraventricular tumors had a partly blurred border with ventricle wall. Four tumors had mild to moderate extent of surrounding edema signals. A slight hydrocephalus was seen in four patients. Incomplete capsule was seen in four tumors at surgery. Histopathologically, mild nuclear atypia was seen in all tumors with a mitotic rate of 2-5 per 10 high-power fields. Conclusion APP should be included in the differential diagnosis when an intraventricular or CPA tumor appearing as a multi-lobulated solid mass with slight heterogeneity, heterogeneous strong enhancement, partly blurred borders, mild to moderate peritumoral edema, or slight hydrocephalus are present.
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Imagen por Resonancia Magnética/métodos , Papiloma del Plexo Coroideo/diagnóstico por imagen , Papiloma del Plexo Coroideo/patología , Adulto , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
OBJECTIVE: To study the features of chordoid glioma of the third ventricle. METHODS: The MRI findings of five cases of chordoid glioma of the third ventricle pathologically proved were reviewed and correlated with operative and pathologic reports. RESULTS: The patients were 3 women and 2 men, 30 - 50 years old in age. The main symptoms were progressive headache, and usually erratic irregular menstruation in women.Five cases of chordoid glioma were located in the third ventricles. Grossly, the 5 tumors size range were 2 - 4 cm in diameter, and were well-circumscribed mass with rounded or irregular morphological features on standard MRI. They were isointense to slightly hypointense relative to normal white matter in T1WI, slightly hyperintense in T2WI and hypointense in DWI on MR. The significant contrast enhancement of this tumour on postcontrast T1WI result from a breakdown of the blood-brain barrier and extravasation of contrast medium, as confirmed by the absence of vascular proliferation on histological examination.4 tumors were enhanced equivalently and 1 tumor had central nonenhancing components representing small cysts, because of its large size (4 cm in diameter). CONCLUSIONS: Chordoid glioma of the third ventricle is rare and the MR appearances possess unique features which are very helpful in diagnosis of chordoid glioma, but to make a definite diagnosis is based on clinical and histopathological features and immunohistochemical staining.
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Neoplasias del Ventrículo Cerebral/patología , Glioma/patología , Tercer Ventrículo/patología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Recognizing renal vascular variants preoperatively is important in order to avoid vascular complications during surgery. This study aimed to investigate the renal vascular variants with dual-energy computed tomography (DECT) angiography to provide valuable information for surgery. METHODS: A total of 378 patients underwent DECT. The number, size, course and relationships of the renal vessels were retrospectively observed from the scans. Anomalies of renal arteries and veins were recorded and classified. Multiplanar reformations (MPR), maximum intensity projections (MIP), and volume renderings (VR) were used for analysis. RESULTS: In 378 patients (756 kidneys), renal artery variations were discovered and recorded in 123 kidneys (16.3%, 123/756) of 106 patients (28.0%, 106/378). Type IB (early branches of the only one main renal artery) and IC (accessory renal artery with only one main renal artery) were found most frequently with an incidence of 11.4% (43/378) and 14.5% (55/378). The incidence of renal artery variations in the left kidney was not statistically different than in the right kidney (12.4% vs. 11.1%). The incidence of renal vein variations was detected in 104 patients (27.5%, 104/378). The incidence of venous variants in the right kidney was higher than in the left kidney (20.1% vs. 7.4%), but left renal vein variations were more complex. Variants of the left renal vein were detected in 28 patients including type 1 (circumaortic left renal vein) in eight cases, type 2 (retroaortic left renal vein) in seven cases, type 3 (abnormal reflux) in six cases, type 4 (late venous confluence of left renal vein) in five cases, and type 5 (rare type) in two cases. The frequency of left renal vein variation associated with the left renal accessory artery was significantly higher than with early branches of the left renal artery (P = 0.037). CONCLUSIONS: The renal vascular variants are rather common and complex. DECT angiography can demonstrate the precise anatomy of the renal vessels, which is a benefit for renal transplantation or other renal operations.
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Angiografía/métodos , Riñón/irrigación sanguínea , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Venas Renales/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: To explore the effect of plasminogen activator inhibitor-1 (PAI-1) on the proliferation and conversion of rat embryonic lung fibroblasts and the synthesis of collagen, and therefore to explore the function of PAI-1 in pulmonary fibrosis. METHODS: The embryonic lung fibroblasts from pregnant Wistar rats were isolated and cultured in vitro. The reproduction rate of fibroblasts at 12 h, 24 h, and 48 h after being stimulated by PAI-1 with different concentrations (5, 10, 20, 40, 80, and 100 µg/L) was measured by MTT assay. After being stimulated by PAI-1 with the most suitable concentration (20 µg/L) for 48 h and 72 h, the expression of proliferating cell nuclear antigen (PCNA) was measured by immunocytochemical technique, and the mRNA expression of α-SMA and type-1 collagen at 24 h and 48 h was measured by real-time PCR. RESULTS: PAI-1 with different concentrations stimulated the proliferation of fibroblasts. The highest proliferation rate and absorbance in concentration of 20 µg/L and at 12 h were 62.6% and 0.573 ± 0.039. The comparison of different concentrations showed that the difference was significant (F = 111.112, P = 0.000). Therefore, 20 µg/L was selected as the most suitable concentration. Using immunocytochemical method, the optical density of PCNA at 48 h and 72 h were 3685 ± 686 and 2530 ± 477 after being stimulated with 20 µg/L PAI-1. The comparison showed significant difference (F = 7.85, P = 0.02). The expression of α-SMA increased (230 ± 11)% and (159 ± 9)% at 24 h and 48 h after being stimulated with 20 µg/L PAI-1, and the difference was significant (F = 39.92, P = 0.0003). The expression of type-1 collagen increased (92 ± 8)% and (65 ± 12)%, the difference being significant (F = 32.61, P = 0.0006). CONCLUSION: PAI-1 can promote the proliferation and conversion of fibroblasts and the synthesis of collagen, which may be involved in the pathogenesis of pulmonary interstitial fibrosis.
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Proliferación Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/farmacología , Animales , Células Cultivadas , Femenino , Fibroblastos/citología , Pulmón/citología , Embarazo , Ratas , Ratas WistarRESUMEN
A self-made new indoor environmental chamber facility for the study of atmospheric processes leading to the formation of ozone and secondary organic aerosols has been introduced and characterized. The characterization experiments include the measurements of wall effects for reactive species and the determination of chamber dependent * OH radical sources by CO-NO(x) irradiation experiments. Preliminary ethene-NO(x) and benzene-NO(x) experiments were conducted as well. The results of characterization experiments show that the wall effects for O3 and NO2 in a new reactor are not obvious. Relative humidity has a great effect on the wall losses in the old reactor, especially for O3. In the old reactor, the rate constant for O3 wall losses is obtained to be 1.0 x 10(-5) s(-1) (RH = 5%) and 4.0 x10(-5) s(-1) (RH = 91%), whereas for NO2, it is 1.0 x 10(-6) s(-1) (RH = 5%) and 0.6 x 10(-6) s(-1) (RH = 75%). The value for k(NO2 --> HONO) determined by CO-NO(x) irradiation experiments is (4.2-5.2) x 10(-5) s(-1) and (2.3-2.5) x 10(-5) s(-1) at RH = 5% and RH 75% -77%, respectively. The average *OH concentration is estimated to be (2.1 +/- 0.4) x 10(6) molecules/cm3 by using a reaction rate coefficient of CO and * OH. The sensitivity of chamber dependent auxiliary reactions to the O3 formation is discussed. Results show that NO2 --> HONO has the greatest impact on the O3 formation during the initial stage, N2O5 + H2O --> 2HNO3 has a minus effect to maximum O3 concentration, and that the wall losses of both O3 and NO2 have little impact on the O3 formation. The results from the ethene-NO(x) and benzene-NO(x) experiments are in good agreement with those from the MCM simulation, which reflects that the facility for the study of the formation of secondary pollution of ozone and secondary organic aerosols is reliable. This demonstrates that our facility can be further used in the deep-going study of chemical processes in the atmosphere.
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Monitoreo del Ambiente/instrumentación , Dióxido de Nitrógeno/química , Ozono/química , Fotoquímica/métodos , Aerosoles/análisis , Atmósfera/análisis , Dióxido de Nitrógeno/análisis , Oxidación-Reducción/efectos de la radiación , Ozono/análisis , Fotólisis , Esmog/análisisRESUMEN
The data of O3, NOx (NO and NO2), CO and SO2 observed at Beijing 325m meteorological tower from June 25 to July 7, 2000 and from July 26 to August 22, 2000 are used to analyze the difference of pollutant concentrations on weekends and weekdays, and its causes. Results show that except SO2, the correlations of O3, NOx, NO, NO2 and CO concentrations between weekends and weekdays are very significant,since they all pass the t-test significance level at alpha = 0.05. The correlation coefficients (R) are 0.99, 0.61, 0.56, 0.80 and 0.61 for O3, NOx, NO, NO2 and CO3, respectively. Weekend NO, and CO concentrations are lower than weekday concentrations in rush hours (06:00-08:00), and the mean deviations for NOx and CO concentrations are -28% and -9%, respectively. The regression coefficient of O3 concentrations between weekends and weekdays is 1.25 +/- 0.02. Furthermore, the maximum 1-h average O3 concentration and maximum 8-h average O3 concentration on weekends are 23% and 26% higher than those on weekdays, respectively, indicating an obvious O3 "weekend effect".
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Contaminantes Atmosféricos/análisis , Óxido Nítrico/análisis , Ozono/análisis , Emisiones de Vehículos/análisis , China , Ciudades , Dióxido de Nitrógeno/análisis , Oxidantes Fotoquímicos/análisis , Estaciones del Año , Dióxido de Azufre/análisisRESUMEN
OBJECTIVE: To evaluate the therapeutic effects of auricular plaster therapy for obstructive sleep apnea syndrome (OSAS) and the influence on sleeping structure. METHODS: 45 OSAS patients were randomly divided into a treatment group of 30 cases and a control group of 15 cases for comparison of the changes in parameters of respiration and sleep at night. RESULTS: The auricular plaster therapy significantly improved the hypoventilation index, respiratory disturbance index and other respiratory parameters as well as the sleeping parameters such as the time and rate of sleep at stage I and II, and the waking time and rate. CONCLUSION: Auricular plaster therapy may show good therapeutic effects for OSAS, and with the advantages of low cost and less side effects.
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Acupresión , Pabellón Auricular , Apnea Obstructiva del Sueño/terapia , Puntos de Acupuntura , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Respiración , Apnea Obstructiva del Sueño/fisiopatologíaRESUMEN
Hai1, a Gossypium barbadense L. variety with super fiber quality, and CCRI36 and Zhong221, two upland cotton cultivars (Gossypium hirsutum L.), were used as recurrent parents to develop two backcross combinations of CCRI36xHai1 and Zhong221xHai1. Fiber quality of inter-crossing bolls and self-crossing bolls were analyzed from different generations of the two combinations. The results showed that there existed significant difference in the average value, pole difference and CV% of fiber quality traits, and no significant correlation in fiber quality traits between inter-crossing bolls (BC2F0) and self-crossing bolls (BC1F1) from male parent plants. There existed no significant difference in the average value, pole difference and CV% of fiber quality traits between inter-crossing bolls (BC2F0) and self-crossing bolls from the recurrent parents when BC1F1 plants were used as male parents and the recurrent parents (CCRI36, Zhong221) as female parents. The results also showed that average value, pole difference and CV% of fiber traits of inter-crossing bolls (BC3F0) were close to those of the female parents (BC2F1). When BC2F1 populations were used as female parents and the recurrent parents (CCRI36, Zhong221) were used as male parents, there were extremely significant positive correlation for fiber length, strength, micronaire value and elongation, except for fiber uniformity between inter-crossing bolls (BC3F0) and self-crossing bolls (BC2F1). So, fiber quality of inter-crossing bolls were close to those of self-crossing bolls of maternal plants and the male parent pollen genotype had no prominent effect to fiber quality traits of inter-crossing bolls. Fiber quality traits were controlled mainly by maternal plant genotype, while the contemporary seed embryonal genotype showed no significant effects for fiber quality.
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Fibra de Algodón , Gossypium/anatomía & histología , Gossypium/genética , Genotipo , Hibridación GenéticaRESUMEN
OBJECTIVE: To evaluate the effectiveness of de-escalation therapy (DET) in patients with severe lower airway infection in the respiratory care unit. METHODS: Sixty-seven cases of severe lower airway infection (SLAI) were divided into two groups: a DET group (n = 29), and a non-DET group (NDET, n = 38). Samples of lower airway secretions were collected by blinded protected specimen brush for culture and Gram stain. The clinical data were compared between the DET group and the NDET group, including the time of mechanical ventilation, time of stay in hospital, APACHE-II score, treatment responses and outcome, cost of antibiotics and total cost in the hospital. RESULTS: There were significant differences in time in hospital (14 +/- 8; 19 +/- 12), the time of mechanical ventilation (22 +/- 16; 32 +/- 16) and the total cost in-hospital (52 871 +/- 54 457; 82 913 +/- 49 564. t = 2.195, 2.449, 2.354, all P < 0.05), while there was no significant difference in the cost on antibiotics between the DET group (7896 +/- 4718) and the NDET group (8490 +/- 5786. t = 0.449, P > 0.05). The mortality and inappropriate antibiotic therapy rate of the DET group (13.8%, 27.6%) were lower than those of the NDET group (36.8%, 60.5%; chi(2) = 4.45, 7.18, all P < 0.05). CONCLUSION: The mortality of SLAI was significantly decreased by DET. DET also led to shorter time of mechanical ventilation, shorter course of therapy and less total cost of therapy.
Asunto(s)
Antibacterianos/administración & dosificación , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/economía , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/economía , Antibacterianos/uso terapéutico , Análisis Costo-Beneficio , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Respiración Artificial , Infecciones del Sistema Respiratorio/mortalidad , Resultado del TratamientoRESUMEN
OBJECTIVE: To explore the changes of the platelet function and serum anticardiolipin antibody (ACA) in patients with pulmonary thromboembolism (PTE). METHODS: Forty-eight patients with PTE diagnosed by spiral computed tomographic pulmonary angiography (CTPA) were included as the trial group, while 20 person in which PTE was excluded served as the control group. P-selectin, and GPIIb/IIIa expressed on platelets were measured by flow cytometry, and plasma TXB(2), 6-Keto-PGF1alpha, vWF, D-dimer and serum ACA were measured by ELISA and the changes of these parameters were compared 1 week later. RESULTS: In the trial group, the levels of P-selectin, GPIIb/IIIa, TXB(2), vWF, D-dimer and T/K were significantly higher than those in the control group (P < 0.01). But the plasma level of 6-Keto-PGF1alpha in the patients with PTE was significantly lower than that in the control group (P < 0.01). The levels of ACA-IgG and ACA-IgA were significantly higher than those in the control group (P < 0.01). After therapy the level of 6-Keto-PGF1alpha was significantly higher than that before therapy (P < 0.01), and other parameters were significantly lower than those before therapy (P < 0.01). P-selectin, GPIIb/IIIa and vWF were positively correlated with D-dimer (P < 0.01). CONCLUSION: Endothelium damage, platelet activation and hypercoagulation combined with fibrinolytic activation occur in patients with PTE.