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1.
Phys Rev E ; 110(2-1): 024125, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39294999

RESUMEN

In one-dimensional low-density Jaynes-Cummings Hubbard (JCH) models [Phys. Rev. E 106, 064107 (2022)2470-004510.1103/PhysRevE.106.064107], we proved that the eigenstate thermalization hypothesis (ETH) is valid when the tunneling strength and coupling strength are of the same order. Surprisingly, at the weak tunneling limit, we observed that the entanglement entropy and scaling law of kinetic energy operators also exhibit obvious quantum chaotic properties, this is an unexpected result. To substantiate these findings, we further discuss their nonequilibrium dynamics in this paper. Our analysis reveals that when the model is a weak tunneling limit after the quench and the initial state is an equilibrium state of chaos, the system reaches an equilibrium state. This observation supports the conclusion that the low-density JCH model at the weak tunneling limit is nonintegrable, corroborating our previous results [Phys. Rev. E 106, 064107 (2022)2470-004510.1103/PhysRevE.106.064107]. Additionally, by discussing the validity of the fluctuation-dissipation theorem (FDT) and the evolution behavior of entanglement entropy and fidelity, we numerically demonstrate the differences between the one-dimensional low-density JCH model and general nonintegrable systems. Specifically, in the low-density JCH model, when the Hamiltonian after the quench is integrable, the validity of FDT depends on the thermal behavior of the initial Hamiltonian, and a metastable state is observed during the evolution of entanglement entropy. Our research presents an an intriguing and unique nonintegrable model, enriching the current understanding of nonintegrable systems.

2.
Phys Rev E ; 106(6-1): 064107, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36671177

RESUMEN

In the one-dimensional low-density Jaynes-Cummings Hubbard (JCH) model, we find that when the hopping strength is much smaller than the coupling strength, the average restricted energy gap ratio exhibits an abnormal statistical behavior that is neither a Poisson nor a Gaussian orthogonal ensemble. But the average half-chain entanglement entropy exhibits ergodicity, and the eigenstate thermalization hypothesis (ETH) is valid for the observable. These results are quite different from those of the standard JCH model. In addition, when the hopping and the coupling strengths are of the same order, quantum chaos still appears in the low-density JCH model, which is in contrast to the integrability of the one-dimensional hard-core bosons. Finally, the dipole-dipole interaction breaks the particle-hole symmetry and leads the abnormal statistical properties to be closer to those of the integrable system at the weak hopping strength limit, but the quantum chaos properties cannot be affected when the hopping strength is of the same order as the coupling strength. Our results demonstrate the counterintuitive behavior in the low-density JCH model and explain the physics behind them from the perspective of the energy spectrum.


Asunto(s)
Entropía , Distribución Normal
3.
Leuk Res ; 75: 1-6, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30419548

RESUMEN

Tyrosine kinase inhibitors have achieved unprecedented efficacy in the treatment of chronic myeloid leukemia (CML); however, imatinib resistance has emerged as a major problem in the clinic. Because the overexpression of BCR-ABL1 critically contributes to CML pathogenesis and drug resistance, targeting the regulation of BCR-ABL1 gene expression may be an alternative therapeutic strategy. In this study, we found that the transcriptional repressor MXD1 showed low expression in CML patients and was negatively correlated with BCR-ABL1. Overexpression of MXD1 markedly inhibited the proliferation of K562 cells and sensitized the imatinib-resistant K562/G01 cell line to imatinib, with decreased BCR-ABL1 mRNA and protein expression. Further investigation using reporter gene analysis showed that MXD1 significantly inhibited the transcriptional activity of the BCR-ABL1 gene promoter. Taken together, these data show that MXD1 functions as a negative regulator of BCR-ABL1 expression and subsequently inhibits proliferation and sensitizes CML cells to imatinib treatment.


Asunto(s)
Antineoplásicos/farmacología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Resistencia a Antineoplásicos/genética , Mesilato de Imatinib/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas Represoras/genética , Proteínas de Fusión bcr-abl/genética , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Humanos , Células K562
4.
Sci Rep ; 8(1): 14367, 2018 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-30254281

RESUMEN

We theoretically investigate the optomechanically induced transparency (OMIT) phenomenon in a N-cavity optomechanical system doped with a pair of Rydberg atoms with the presence of a strong control field and a weak probe field applied to the Nth cavity. It is found that 2N - 1 (N < 10) numbers of OMIT windows can be observed in the output field when N cavities couple with N mechanical oscillators and the mechanical oscillators coupled with different even- or odd-labelled cavities can lead to diverse effects on OMIT. Furthermore, the ATS effect appears with the increase of the effective optomechanical coupling rate. On the other hand, two additional transparent windows (extra resonances) occur, when two Rydberg atoms are coupled with the cavity field. With DDI strength increasing, the extra resonances move to the far off-resonant regime but the left one moves slowly than the right one due to the positive detuning effect of DDI. During this process, Fano resonance also emerges in the absorption profile of output field.

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-703569

RESUMEN

Objectives:This study aims to analyze the current status of the collaboration of medical staff among county,township,and village with comprehensive prevention and control of chronic diseases based on nine dimen-sions of DMIC integrated medical service development model,with a view to providing medical services collaboration on chronic diseases across the organization to provide direction for improvement. Methods:278 health workers sam-pled by the combination of typical sampling and multi-stage random sampling method received a questionnaire and the results were analyzed statistically. Results:According to the findings of this study,village doctors show higher partic-ipation in chronic care collaboration,but they are faced with the aging population and most of them are poorly educat-ed;the multi-institutional collaboration is of low efficiency in practice although it is well accepted by all health work-ers;there is no existing shared health information system among county,township and village. Conclusion:These re-sults suggest that the government should strengthen its leadership and promote primary health care management through medical staff collaboration;initiatives of health workers should be stimulated to promote the continuity of medical serv-ices;the shared health information system should be set up to facilitate the health workers' collaboration.

6.
Journal of Experimental Hematology ; (6): 1713-1717, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-278756

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effect of myeloma-derived exosomes on surface activating receptors of NK cells, and to explore the mechanism of the function defect of NK cells.</p><p><b>METHODS</b>The exosomes from the supernatant of multiple myeloma cell lines RPMI8226 and U266 were extracted by ultracentrifugation, and the size of them was identified under electron microscope; the human primary NK cells were extracted, and were co-cultured with the myeloma-derived exosomes (40 µg/ml), then the expression levels of surface activating receptors NKp46, NKp30 and NKG2D of NK cells at 0,1,4 and 24 hours were detected by flow cytometry.</p><p><b>RESULTS</b>The exosomes showed small vesicular, sized 30-100 nm under electron microscope. The expression of surface activating receptors of NK cells declined at different degree after co-cultured with myeloma-derived exosomes.</p><p><b>CONCLUSION</b>Myeloma-derived exosomes can inhibit the expression of surface activating receptors of NK cells.</p>

7.
Huan Jing Ke Xue ; 34(9): 3669-74, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289021

RESUMEN

Soil samples were collected from 18 sites at a relocated lead accumulator factory in the Southwest region, China. Among the 15 sample sites, profile soil samples at 0-20 cm, 20-40 cm and 40-60 cm were taken. Soil lead contents were analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Characteristics of Pb in topsoil and soil profiles collected from different sampling sites were discussed. Results showed that: (1) The total Pb contents in topsoil (0-20 cm) ranged from 18.18 to 52,332.50 mg x kg(-1). The maximum content greatly exceeded the national standard (HJ 350-2007). The Pb concentration in different workshops followed a decreasing order: the fourth workshop > the second workshop > waste lead storage pit > sewage works > the third workshop > the fifth workshop > the first workshop > the original fourth workshop > the packing workshop > the office area. (2) Results of profile distribution showed that soil depth had no significant effect on Pb content. Lead can be highly accumulated at different depths of the soil, which was quite different from natural soils. (3) Hakanson's potential ecological risk index evaluation showed that there was widespread ecological risk in the soil of the plant, and serious ecological risk existed in some workshops where a large number of lead was enriched. Therefore, the site must be restored in order to reuse it.


Asunto(s)
Plomo/análisis , Contaminantes del Suelo/análisis , Suelo/química , China , Monitoreo del Ambiente , Industrias
8.
Huan Jing Ke Xue ; 34(9): 3679-83, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289023

RESUMEN

In this research, six topsoil samples (0-20 cm) were collected in the heavy-metal lead contaminated soil of one lead battery factory in south-west China as research object, which were later divided into seven particle size fractions, and analyzed for the lead concentration as well as the correlation between the lead concentration and the organic matter content. The result showed that five soil samples were contaminated with lead with different pollution levels, and there were two different trends in the changes of lead concentration as of the change of soil particle size. The lead concentration of the three samples from sewage treatment workshop, the workshop A and the workshop B, showed a first declining and then ascending trend with the decreasing particle size. The lead concentration of the soil samples of the packing workshop and the former production workshop A showed a decreasing trend when the particle size decreased. The lead concentration and the organic matter content showed a positive linear correlation (R2 = 0.8232). Soil organic matter has the ability of lead enrichment, and the ability declines with the decreasing particle size. Soil texture may be an important factor for the interaction between soil organic matter and lead distribution.


Asunto(s)
Plomo/análisis , Tamaño de la Partícula , Contaminantes del Suelo/análisis , Suelo/química , China , Industrias
9.
Huan Jing Ke Xue ; 34(9): 3697-703, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289026

RESUMEN

Lead-contaminated soil with different pollution load in a lead battery factory in the southwest of China was chosen as the research object, the lead content and speciation were analyzed, and different washing agents were screened. The lead washing efficiency and lead speciation were analyzed under different pH conditions, and the soil of different particle size was washed using different duration to determine the best washing time. The results showed that the soil of sites A and B in the factory was severely contaminated, the lead concentration reaching 15,703.22 mg x kg(-1) and 1747.78 mg x kg(-1), respectively, and the proportion of the active-state lead was relatively high, while the residue state accounted for only 17.32%, 11.64%, 14.6% and 10.2%. EDTA and hydrochloric acid showed the best extraction effect in the 5 washing agents tested, which included EDTA, hydrochloric acid, citric acid, rhamnolipid and SDS. Cleaning under acidic conditions could not only effectively extract the total amount of lead but also effectively reduce the environmental risk of active-state lead. pH 4-7 was suggested as the most appropriate condition. The cleaning effect of coarse sand and fine sand was good, while for washing powder clay, it is better to improve the process, with the optimal washing time determined as 240 min.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Plomo/química , Contaminantes del Suelo/química , Suelo/química , China , Ácido Cítrico , Ácido Clorhídrico , Industrias , Tamaño de la Partícula , Dióxido de Silicio
10.
Huan Jing Ke Xue ; 34(9): 3704-8, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289027

RESUMEN

This research chose five lead-contaminated sites of a lead-acid battery factory to analyze the speciation distribution and concentration of lead. Under the same conditions (0.1 mol x L(-1) EDTA,30 min, 25 degrees C), the removal effect of heavy metal was compared between ultrasonic-assisted chemical extraction (UCE) and conventional chemical extraction ( CCE), and the variation of lead speciation was further explored. The results showed that the lead removal efficiency of UCE was significantly better than CCE. The lead removal efficiency of WS, A, B, C and BZ was 10.06%, 48.29%, 48.69%, 53.28% and 36.26% under CCE. While the removal efficiency of the UCE was 22.42%, 69.31%, 71.00%, 74.49% and 71.58%, with the average efficiency higher by 22%. By comparing the speciation distribution of the two washing methods, it was found that the acid extractable content maintained or decreased after UCE, whereas it showed an increasing trend after CCE. The reduction effect of the reducible was as high as 98% by UCE. UCE also showed a more efficient reduction effect of the organic matter-sulfite bounded form and the residual form. Hence, it is feasible to improve the washing efficiency of heavy metal contained in soil by conducting the cleaning process with the help of ultrasonic wave, which is a simple and fast mean to remove lead from contaminated sites.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Plomo/química , Contaminantes del Suelo/química , Suelo/química , Ultrasonido , Ácidos , Industrias
11.
Huan Jing Ke Xue ; 34(9): 3709-15, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289028

RESUMEN

Attrition scrubbing was used to remediate lead contaminated-site soil, and the main purpose was to remove fine particles and lead contaminants from the surface of sand. The optimal parameters of attrition scrubbing were determined by orthogonal experiment, and three soil samples with different lead concentration were subjected to attrition scrubbing experiments. The results showed that the optimal scrubbing parameters were: a solid ratio of 70% dry matter, a temperature of 25 degrees C, an attrition time of 30 min, and an attrition speed of 1200 r x min(-1). Before attrition scrubbing, the screening and analysis of soil showed that in all three soil samples, lead was mainly enriched on sand and fine particles, and the distribution of lead was highly correlated to the organic matter. After attrition scrubbing, the washing efficiency of the original state lead contaminated sand soil in triplicates was 67.61%, 31.71% and 41.01%, respectively, which indicates that attrition scrubbing can remove part of the fine soil and lead contaminants from the surface of sand, to accomplish the purpose of pollutants enrichment. Scanning electron microscopy (SEM) analysis showed that the sand surface became smooth after attrition scrubbing. The results above show that attrition scrubbing has a good washing effect for the remediation of lead contaminated sand soil.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Plomo/química , Contaminantes del Suelo/química , Suelo/química , Dióxido de Silicio
12.
Huan Jing Ke Xue ; 34(1): 401-8, 2013 Jan.
Artículo en Chino | MEDLINE | ID: mdl-23487968

RESUMEN

Constructed wetlands as a wastewater eco-treatment technology are developed in recent decades. It combines sewage treatment with the eco-environment in an efficient way. It treats the sewage effectively, and meanwhile beautifies the environment, creates ecological landscape, and brings benefits to the environment and economics. The unique advantages of constructed wetlands have attracted intensive attention since developed. Constructed wetlands are widely used in treatment of domestic sewage, industrial wastewater, and wastewater from mining and petroleum production. However, many problems are found in the practical application of constructed wetland, e. g. they are vulnerable to changes in climatic conditions and temperature, their substrates are easily saturated and plugged, they are readily affected by plant species, they often occupy large areas, and there are other problems including irrational management, non-standard design, and a single function of ecological service. These problems to a certain extent influence the efficiency of constructed wetlands in wastewater treatment, shorten the life of the artificial wetland, and hinder the application of artificial wetland. The review presents correlation analysis and countermeasures for these problems, in order to improve the efficiency of constructed wetland in wastewater treatment, and provide reference for the application and promotion of artificial wetland.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Administración de Residuos/métodos , Humedales , Biodegradación Ambiental , Arquitectura y Construcción de Instituciones de Salud , Eliminación de Residuos Líquidos/economía , Eliminación de Residuos Líquidos/instrumentación
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 13(11): 886-8, 2011 Nov.
Artículo en Chino | MEDLINE | ID: mdl-22099197

RESUMEN

OBJECTIVE: To study the diagnosis of vasovagal syncope (VVS) in children with postural orthostatic tachycardia syndrome (POTS). METHODS: The clinical data of 57 children with POTS diagnosed by the head-up tilt test between January 2007 and December 2010 were studied retrospectively. Of the 57 children, there were 29 boys and 28 girls who were aged from 5 to 16 years (12.2±1.9 years). RESULTS: Twenty-four (42%) out of 57 children were diagnosed with VVS by prolonging the duration of the head-up tilt test (for the children with orthostatic tolerance): cardioinhibitory (20 cases), mixed (3 cases) and vasoinhibitory (1 case). The POTS children with VVS were older than those without (13.0±1.4 years vs 11.5±2.1 years; P<0.05). There were no significant differences in gender and clinical symptoms between the POTS children with and without VVS. CONCLUSIONS: Some children with POTS may have coexisting VVS, suggesting that it is important to avoid misdiagnosis of VVS by prolonging the duration of head-up tilt test in POTS children with orthostatic tolerance. There are no obvious differences in gender and clinical symptoms between the POTS children with and without VVS.


Asunto(s)
Síndrome de Taquicardia Postural Ortostática/complicaciones , Síncope Vasovagal/diagnóstico , Adolescente , Niño , Preescolar , Errores Diagnósticos , Femenino , Humanos , Masculino , Pruebas de Mesa Inclinada
14.
Journal of Leukemia & Lymphoma ; (12): 218-221, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-471182

RESUMEN

Objective To investigate sequence variations of 12 miRNA genes in multiple myeloma(MM) in order to find whether sequence variations in miRNA genes are associated with tumorigenesis and discuss the clinical significance of MM associated with miRNA genes mutations. Methods The miRNA gene mutations in 20 cases of MM, 4 MM-derived cell lines and 20 controls were detected by the methods of polymerase chain reaction single stranded conformation polymorphism (PCR-SSCP) and silver staining technique. Both clinical features and laboratory results were analyzed simultaneously. Results The electrophoretic patterns showed a total of three variations in miR-19a, miR-19b and miRNA-335,which were observed in 3 MM cells (15 %, 3/20). We also found variations of miRNA-335 in MM-derived cell lines KM-3and RPMI8226. However, no sequence alteration in the miRNA genes was observed in our set of controls. One of the three MM patients died, and two of them were detected mutations at the terminal stage of the disease.Conclusion A relative high frequency of miRNA gene mutation was found in MM and MM derived cell lines, which suggests possibility of a main mechanism underlying tumorigenesis. And, detecting miRNA gene mutations in MM might be benefit to evaluate the progression and prognosis of disease.

15.
Journal of Leukemia & Lymphoma ; (12): 357-361, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-472873

RESUMEN

Objective To investigate the reversal effect of Topo Ⅱα-shRNA and Topo Ⅱβ-shRNA on Topo Ⅱ gene in K562/AS2 cells. Methods Three pieces of Topo Ⅱα-shRNA and three pieces of Topo Ⅱβ-shRNA were designed,synthesized and transfected into K562/AS2 cells by liposome. Expression level of Topo Ⅱα and Topo Ⅱβ mRNA were determined by real time fluorescence quantitative PCR. The expressions of Topo Ⅱα and Topo Ⅱβ protein were assayed with flow cytometer. Results After treated with Topo Ⅱα-shRNA or Topo Ⅱβ-shRN A for 24 hours,the expression level of Topo Ⅱα mRNA and Topo Ⅱβ mRNA protein in K562/AS2 cells decreased at most (78.22±0.01) %,(31.17±1.27) % (P <0.05),and (57.36±0.01)%,(23.98±1.22) % (P <0.05) respectively. Conclusion The expression of Topo Ⅱ gene can be down-regulated after infected with Topo Ⅱ-shRNA in K562/ AS2 cell line.

16.
Journal of Leukemia & Lymphoma ; (12): 652-655, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-474380

RESUMEN

ObjectiveTo investigate the gene expressions of TAZ and Wnt/β-catenin on the postosteogenic cells of mesenchymal stem cells(MSC)in multiple myeloma(MM)patients and to explore the potential therapeutic target of multiple myeloma bone disease (MBD).MethodsBone marrow mononuclear cells MNC from MM and controls were isolated,cultured,expanded and then induced to osteogenic differentiation.Realtime quantitative RT-PCR was employed to detect the osteogenic markers (TAZ,Wnt/β-catenin,OPN,OC,ALP and Cbf α1); and alizarin red staining for mineral deposition.The mRNA expressions of TAZ and Wnt/β-catenin in the two groups were analysed.ResultsAlizarin red staining was positive and the red calcium nodules were appeared on the post-osteogenic cells of MSC.The mRNA expressions of OC,ALP and Cbf α1 were 2.0958±0.5665,2.6670±0.3847,0.8463±0.3473,respectively,on the post-osteogenic cells of MSC in the experimental groups,which were significantly higher than those of pre-osteogenic cells(1.3487±0.9291,1.1452±0.6054,0.4439±0.2945) (t =2.171,6.709,2.795; all P < 0.05).The mRNA expressions of OPN,OC,ALP and Cbf α1 were 2.1096±0.8267,2.8991±0.3531,4.3045±0.2844,1.3273±0.4075,respectively,on the post-osteogenic cells of MSC in the controls,which were significantly higher than those of pre-osteogenic cells (1.2200±0.9091,0.8780±0.3927,1.9161±0.2684,0.6736±0.2513) (t =2.289,12.103,25.134,4.411; all P < 0.05).The mRNA expressions of OPN,OC,ALP,Cbf α1 were 1.2710±0.5636,2.0958±0.5665,2.6670± 0.3847,0.8463+0.3473,respectively,on the post-osteogenic cells of MSC in the experimental groups,which were significantly lower than those of control groups(2.1096 ±0.8267,2.8991 ±0.3531,4.3045±0.2844,1.3273±0.4075) (t =-2.650,-3.805,-10.822,-2.841; all P < 0.05).The mRNA expression of TAZ and β-catenin were 2.2315±1.0723 and 0.5801±0.2159 on the post-osteogenic cells of MSC in MM patients,which were significantly lower than those of control groups (4.4140±0.8325,0.9516±0.2920) (t =±5.085,-3.235;both P < 0.05).ConclusionThe gene expressions of OPN,OC,ALP and Cbf α1,the osteogenesis related genes,are increased in post-osteogenic cells of MSC,which showed the MSC have been successfully induced to osteoblasts.Comparing with control groups,the osteogenic potential of MSC in MM patients is lower.Based on the above research,TAZ and Wnt/β-catenin may present a novel target for the future therapy of MBD.

17.
Journal of Leukemia & Lymphoma ; (12): 276-280, 2010.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-472244

RESUMEN

Objective To construct a recombinant adenovirus vector of Hairpin RNA specific for MRP1 gene and study its inhibition of MRP1 gene expression in K562/AS2 cell line resistant to AS_2O_3 (ATO). Methods A MRP1-specific hairpin RNA recombinant adenovirus vector was constructed and used to infected K562/AS2 cells. Expression level of MRP1 mRNA detected by real-time fluorescent quantitative PCR. MRP1 protein detected by flow cytometry. MTT method was used to detected the cytotoxicity of ATO and etoposide. Results MRP1 mRNA and protein expression level in K562/AS2 cells before and after the pAd-MRPl-shRNA adenovirus infection was (34.70±0.28 vs 4.19±0.03, P <0.05) and (26.40±0.16 vs 10.85±0.37, P<0.05), respectively. RR of K562/AS2 to arsenic trioxide and etoposide was (11.4078±0.3183 fold vs 1.6126±0.3015 fold, P<0.05) and (5.9141 ±0.0149 fold vs 1.7664±0.1038 fold, P <0.05), respectively. The reversal fold of ATO and etoposide was (7.2409±1.3668) and (3.3555±0.1886), respectively. Conclusion Successfully constructed pAd-EGFP-U6-shRNA-MRPl adenovirus vector, the vector of infection K562/SA2 cells can inhibit MRP1 gene expression and reverse the resistance of the ATO and etoposide.

18.
Ying Yong Sheng Tai Xue Bao ; 18(9): 2013-8, 2007 Sep.
Artículo en Chino | MEDLINE | ID: mdl-18062305

RESUMEN

There are many difficulties in ascertaining the area that needs to be remedied in contaminated site. This paper integrated the experts' judgments with grids as the sampling strategy in an abandoned pesticide plant in northern China, and applied a geostatistical method, inverse distance weighted interpolation (IDW), to simulate the pollutants- and risk spatial distribution. Based on soil environmental benchmark, two scenarios were designed for ascertaining the polluted area. The results showed that the area needed to be remedied and determined by IDW was somewhat larger, according to the national environmental 2nd standard for agricultural soils, but the area and cost needed for remedy were smaller and more economic and reasonable, based on the health risk threshold level and IDW method. A combination of IDW and health risk assessment in ascertaining polluted area would be a new way for site assessment and soil remediation in the future.


Asunto(s)
Monitoreo del Ambiente/métodos , Salud Pública/métodos , Contaminantes del Suelo/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Residuos Peligrosos/análisis , Matemática , Salud Pública/estadística & datos numéricos , Medición de Riesgo
19.
Ying Yong Sheng Tai Xue Bao ; 18(8): 1869-76, 2007 Aug.
Artículo en Chino | MEDLINE | ID: mdl-17974259

RESUMEN

Ecological risk is a hotspot in the present environmental management study, which mainly focuses on the chemical, physical, and biological stressors that may damage ecosystem or its components. Ecological risk assessment (ERA) has a great significance for making scientific environmental management strategies. In order to lessen the damage of ecosystem or its parts, and to manage the ecosystem effectively, it is necessary to predict the probability the adverse ecological effects would occur and the consequences. This paper summarized the research methods, tools and trends of ERA, and pointed out the areas that need to be further studied. It was suggested that under the background of urbanization, urban ecological risk should be given more attentions. The prospects of further study were discussed, based on the issues existed in current researches.


Asunto(s)
Ecología , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Animales , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/prevención & control , Humanos , Modelos Biológicos , Medición de Riesgo
20.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-566256

RESUMEN

Objective To evaluate the influence of tissue factor pathway inhibitor 2(TFPI-2)gene on the proliferation and invasion of K562.Methods The expression vector pcDNA3.0/TFPI-2 was transfected into human leukemia line K562 cells(K562-T)by using liposome,then the mRNA and protein TFPI-2 were detected by real-time RT-PCR and western blot separately.The growth curve and the colony-forming unit assay were used to measure the ability of cells growth and transwell chamber model was employed to test the ability of cell invasion in vitro.Results Expression of mRNA and protein of TFPI-2 was detected in transfected cells.The growth rate and self-replication ability of K562-T cells were lower than those of the two control groups obviously.The number of K562-T cells to traverse a Matrigel-coated membrane was dramatically decreased compared with that of non-expressing cells.Conclusion The gene of TFPI-2 can inhibit the growth,proliferation and invasion of the K562 cells.

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