This paper examines the phenomenon of sociocultural transfer and its motivating factors within the realization patterns of speech act refusal by Chinese EFL learners. EFL refusal data were collected using a written da...This paper examines the phenomenon of sociocultural transfer and its motivating factors within the realization patterns of speech act refusal by Chinese EFL learners. EFL refusal data were collected using a written data collection test (DCT), which was designed and then followed by semi-structured interviews. Using semantic formulas as units of analysis, EFL refusal responses were compared with similar data elicited from native speakers of English. The results show two areas in which sociocultural transfer is existent in EFL learners' speech: options of selecting semantic formulas and content of semantic formulas. Each was found to reflect cultural values transferred from Chinese to English. Furthermore, based on the interview data, it was found that learners' social system and political factors, traditional socio-psychological ideology and economy possibly motivate sociocultural transfer.展开更多
Pandemic outbreaks disrupt agricultural trade.The possible strengthening of import barriers to products from countries at the epicenter of a pandemic by their trade partners could aggravate this situation.This paper e...Pandemic outbreaks disrupt agricultural trade.The possible strengthening of import barriers to products from countries at the epicenter of a pandemic by their trade partners could aggravate this situation.This paper examines the responses of the US Food and Drug Administration(FDA),import refusals,and subsequent trade impacts on the agricultural exports from the developing countries that were the epicenters of four pandemics in the past two decades.Using monthly data for the period 2002-2020,we find increased import refusals and amplified trade-impeding impacts on agricultural exports during pandemic outbreaks.Increased import refusals and the amplification of the trade-impeding effect of import refusals were especially large when China was the epicenter.We further examine possible differences in these results across products and FDA inspection methods,and the main conclusions remain robust.This paper offers a better understanding of the economic outcomes of pandemic outbreaks and provides policy suggestions for China.展开更多
In complex environments such as high dynamics and weak signals,a satellite signal compensation method based on prefabricated trajectory assistance and an improved adaptive Kalman filter is proposed for a 155 mm differ...In complex environments such as high dynamics and weak signals,a satellite signal compensation method based on prefabricated trajectory assistance and an improved adaptive Kalman filter is proposed for a 155 mm differential rotating rear-body control-guided projectile to address the situation of satellite signal flickering and loss in projectile navigation systems due to environmental limitations.First,establish the system state and measurement equation when receiving satellite signals normally.Second,a seven-degree-of-freedom external ballistic model is constructed,and the ideal trajectory output from the ballistic model is used to provide the virtual motion state of the projectile,which is input into a filter as a substitute observation when satellite signals are lost.Finally,an adaptive Kalman filter(AKF)is designed,the proposed adaptive Kalman filter can accurately adjust the estimation error covariance matrix and Kalman gain in real-time based on information covariance mismatch.The simulation results show that compared to the classical Kalman filter,it can reduce the average positioning error by more than 38.21%in the case of short-term and full-range loss of satellite signals,providing a new idea for the integrated navigation of projectiles with incomplete information under the condition of satellite signal loss.展开更多
This paper is to present a typology of refusal strategies which may be employed in the analysis of refusal performance from a discourse approach.Some previous research carried out is reviewed in order to classify non-...This paper is to present a typology of refusal strategies which may be employed in the analysis of refusal performance from a discourse approach.Some previous research carried out is reviewed in order to classify non-native speakers' production of this speech act.Then,the suggested taxonomy will be described in a systematized way from an interlanguage pragmatic perspective and within a conversational analysis framework.Finally,it is emphasized that effective communicative competence plays an important role in the production of this face-threatening speech act of refusing.展开更多
A three-dimensional numerical model verified by previous experimental data is developed to simulate the fluidized bed gasification of refuse derived fuel （RDF）. The CaO dechlorination model obtained by the thermal g...A three-dimensional numerical model verified by previous experimental data is developed to simulate the fluidized bed gasification of refuse derived fuel （RDF）. The CaO dechlorination model obtained by the thermal gravity analysis （TGA） is coupled to investigate the process of CaO dechlorination. An Eulerian-Eulerian method is adopted to simulate the gas-solid flow and self-developed chemical reaction modules are used to simulate chemical reactions. Flow patterns, gasification results and dechlorination efficiency are obtained by numerical simulation. Meanwhile, simulations are performed to evaluate the effects of Ca/Cl molar ratio and temperature on dechlorination efficiency. The simulation results show that the presence of bubbles in the gasifier lowers the CaO dechlorination efficiency. Increasing the Ca/Cl molar ratio can enhance the dechlorination efficiency. However, with the temperature increasing, the dechlorination efficiency increases initially and then decreases. The optimal Ca/Cl molar ratio is in the range of 3. 0 to 3. 5 and the optimal temperature is 923K.展开更多
Edward Hall offers us an effective means of examining cultural similarities and differences,that is the classification of high-context and low-context culture.The paper attempts to analyze a case of a Chinese refusal ...Edward Hall offers us an effective means of examining cultural similarities and differences,that is the classification of high-context and low-context culture.The paper attempts to analyze a case of a Chinese refusal from the perspective of highcontext and low-context communication and explores the differences between the two types of communication.展开更多
Objective: To assess the prevalence of HIV infection, to highlight HIV-testing refusal rates among participants in a population-based tuberculosis survey and to assess the implication for programme implementation.Meth...Objective: To assess the prevalence of HIV infection, to highlight HIV-testing refusal rates among participants in a population-based tuberculosis survey and to assess the implication for programme implementation.Methods: This cross-sectional study on the characteristics of participants who refused HIV testing was conducted in a national survey in Zambia. All eligible participants were aged above 15 years and included in the analysis.Results: Out of the 44 791 tuberculosis survey participants, 14 164(31.6%) refused to participate in HIV testing. The unemployed, rural dwellers, married, and those aged 15-24 years were associated with higher refusal rates.Conclusions: Strategies to improve HIV testing acceptance are necessary. Qualitative research is recommended to understand the reasons for testing refusals so that remedial interventions can be implemented.展开更多
The given article deals with the development of analytical model of request service process by multichannel technical system with unreliable, repaired and reconfigured service facilities. It is assumed that the system...The given article deals with the development of analytical model of request service process by multichannel technical system with unreliable, repaired and reconfigured service facilities. It is assumed that the system is functioning in service mode of random length random request flows. The system considers the existence of time redundancy for afterservice of calls, the service of which is interrupted with refusal, non-depreciating the performed part of the task. Special probability functions are introduced which on the basis of probability reasoning allow to make the systems of integral equations describing the dynamics of request service process.展开更多
Requests and requesting language have been a popular topic for researchers from a wide range of fields including linguistic philosophy,pragmatics,social-pragmatics,and discourse analysis since 1960s.Requesting is a dy...Requests and requesting language have been a popular topic for researchers from a wide range of fields including linguistic philosophy,pragmatics,social-pragmatics,and discourse analysis since 1960s.Requesting is a dynamic process which is the combination of requests and pre-requests,as well as request negotiations.By now,studies mostly focused on the study of how request was initiated and what were the factors lying behind specific choice of one request form over others,and how request-makers pursued their demands when grants were not given as expected.However,limited studies have been published about the development of the strategies children took to avoid predictable refusals.This paper aims to make a contribution to this topic by conducting a longitudinal study lasting for approximately one year with a four-year-old Chinese girl as the subject.By contrasting and comparing the subject’s natural linguistic performance,the author tried to reveal the developmental procedure,and profound cognitive and cultural factors.展开更多
The present study analyzes ten English refusal letters of two subcategories based on Swales' genre analysis model and finds that difference exists in the generic features of the two subcategorized types. Teachers ...The present study analyzes ten English refusal letters of two subcategories based on Swales' genre analysis model and finds that difference exists in the generic features of the two subcategorized types. Teachers should reveal the underlying rationale behind linguistic features of a specific genre so that students can not only identify genre but also apply it appropriately.展开更多
This paper tries to analyze Philip Larkin's poem"High Window"from a deconstructive perspective. It is to show that in the poem the key words/signifiers are always under erasure, and thus the chain of sig...This paper tries to analyze Philip Larkin's poem"High Window"from a deconstructive perspective. It is to show that in the poem the key words/signifiers are always under erasure, and thus the chain of signification is endless since the poem is self-deconstructing. Then, the paper argues that the linguistic features of the poem paradoxically meaningful in the sense that it reflects the poet's skepticism and anxiety.展开更多
Appropriate autophagy has protective effects on ischemic nerve tissue,while excessive autophagy may cause cell death.The inflammatory response plays an important role in the survival of nerve cells and the recovery of...Appropriate autophagy has protective effects on ischemic nerve tissue,while excessive autophagy may cause cell death.The inflammatory response plays an important role in the survival of nerve cells and the recovery of neural tissue after ischemia.Many studies have found an interaction between autophagy and inflammation in the pathogenesis of ischemic stroke.This study outlines recent advances regarding the role of autophagy in the post-stroke inflammatory response as follows.(1)Autophagy inhibits inflammatory responses caused by ischemic stimulation through mTOR,the AMPK pathway,and inhibition of inflammasome activation.(2)Activation of inflammation triggers the formation of autophagosomes,and the upregulation of autophagy levels is marked by a significant increase in the autophagy-forming markers LC3-II and Beclin-1.Lipopolysaccharide stimulates microglia and inhibits ULK1 activity by direct phosphorylation of p38 MAPK,reducing the flux and autophagy level,thereby inducing inflammatory activity.(3)By blocking the activation of autophagy,the activation of inflammasomes can alleviate cerebral ischemic injury.Autophagy can also regulate the phenotypic alternation of microglia through the nuclear factor-κB pathway,which is beneficial to the recovery of neural tissue after ischemia.Studies have shown that some drugs such as resveratrol can exert neuroprotective effects by regulating the autophagy-inflammatory pathway.These studies suggest that the autophagy-inflammatory pathway may provide a new direction for the treatment of ischemic stroke.展开更多
Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their long term stabilization process. In this paper, this process is also referred to as m...Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their long term stabilization process. In this paper, this process is also referred to as mineralization process and the resultant stabilized refuse referred to as aged refuse. Aged refuse contains a wide spectrum and huge quantity of microorganisms with strong decomposition capability for refractory organic matter present in some wastewater such as leachate. In this study, aged refuse excavated from 2 to 10 years old closed landfill compartments in Shanghai Refuse Landfill is characterized in terms of particulate distribution by screening, total nitrogen, total phosphorus, biodegradable matter. The approaches for redevelopment of both land and aged refuse in the stabilized landfills are proposed.展开更多
A field-scale aged refuse （AR） biofilter constructed in Shanghai Refuse Landfill, containing about 7000 m^3 aged refuse inside, was evaluated for its performance in the treatment of landfill leachate. This AR biofil...A field-scale aged refuse （AR） biofilter constructed in Shanghai Refuse Landfill, containing about 7000 m^3 aged refuse inside, was evaluated for its performance in the treatment of landfill leachate. This AR biofilter can be divided into three stages and can manage 50 m^3 landfill leachate per day. The physical, chemical, and biological characteristics of AR were analyzed for evaluating the AR biofilter as leachate treatment host. The results revealed that over 87.8%-96.2% of COD and 96.9%-99.4% of ammonia nitrogen were removed by the three-stage AR biofilter when the infiuent leachate COD and ammonia nitrogen concentration were in the range 5478-10842 mg/L and 811-1582 mg/L, respectively. The final effluent was inodorous and pale yellow with COD and ammonia nitrogen below 267-1020 mg/L and 6-45 mg/L, respectively. The three-stage AR biofilter had efficient nitrification but relative poor denitrification capacity with a total nitrogen （TN） removal of 58%-73%. The external temperature of AR biofilter did not influence the total ammonia nitrogen removal significantly. It was concluded that the scale-up AR biofilter can work very well and can be a promising technology for the treatment of landfill leachate.展开更多
To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laog...To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laogang MSW landfills, Shanghai, China. Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity. The maximum specific cell growth rates （μmax= 0.042 hr-1, R2= 0.995） was derived through Boltzmann simulation, and the apparent half-saturation constants （Km（app） = 7.08 mmol/L, R2 = 0.982） was calculated according to Michaelis-Menton hyperbolic model, indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs. By way of adding the strain JTA1 culture, the methane consumption of aged refuse reached 115 mL, almost two times of control experiment. In addition, high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers. At the chloroform concentration of 50 mg/L, the methane-oxidation rate of bio-cover reached 0.114 mL/（day.g）, much higher than the highest rate, 0.0135 mL/（day.g）, of reported bio-covers. In conclusion, strain JTA1 opens up a new possibility for environmental biotechnology, such as soil or landfills bioremediation and wastewater decontamination.展开更多
Approximately 7000 m^3 of aged refuse （AR） with a placement of over eight years was excavated from Shanghai Refuse Landfill, the largest landfill in China, and used for the construction of a two-stage bioreactor （A...Approximately 7000 m^3 of aged refuse （AR） with a placement of over eight years was excavated from Shanghai Refuse Landfill, the largest landfill in China, and used for the construction of a two-stage bioreactor （AR biofilter） media for the biological treatment of 100 m3 of refuse landfill leachate. It was found that over 64% of COD, 96.9%-99.8% of NH4^＋-N, and 95.8%-99.8% of BOD5 could be removed by the AR biofilter, when the leachate with initial COD, BOD5, and NH4^＋-N concentrations were 986-4128 mg/L, 264--959 mg/L,m and 538-1583 mg/L, respectively. The corresponding concentrations in the effluent were reduced to below 30（000 mg/L, 2-12 mg/L, and 10-20 mg/L, respectively. The effluent was clear and pale yellow with suspended solid below 150 mg/L and color below 150 Pt/Co degree. Meanwhile, the total nitrogen removal was only 49%-63%, indicating a relative poor denitrification capacity of AR biofilter. The effluent pH was neutral and the population of Escherichia coli was less than 10^-1 CFU/mL. Hence, it was considered that the demonstration project can work well for the effective treatment of leachate.展开更多
Biologically-treated municipal solid waste （MSW） leachate still contains many kinds of bit-recalcitrant organic matter. A new plate and frame electrochemical reactor was designed to treat these materials under flow ...Biologically-treated municipal solid waste （MSW） leachate still contains many kinds of bit-recalcitrant organic matter. A new plate and frame electrochemical reactor was designed to treat these materials under flow conditions. In the electrochemical oxidation process, NH3 and color could be easily removed by means of electro-generated chlorinefaypochlorite within 20 min. The effects of major process parameters on the removal of organic pollutants were investigated systematically. Under experimental conditions, the optimum operation parameters were current density of 65 mA/cm^2, flow velocity of 2.6 cm/sec in electrode gap, and initial chloride ion concentration of 5000 mg/L. The COD in the leachate could be reduced below 100 mg/L after 1 hr of treatment. The kinetics and mechanism of COD removal were investigated by simultaneously monitoring the COD change and chlorine/hypochlorite production. The kinetics of COD removal exhibited a two-stage kinetic model, and the decrease of electro-generated chlorine/hypochlorite production was the major mechanism for the slowing down of the COD removal rate in the second stage. The narrowing of the electrode gap is beneficial for COD removal and energy consumption.展开更多
AIM: To assess the feasibility, accuracy and acceptability of PillCam Colon 2 in detection of significant lesions in colorectal cancer risk patients, unable or unwilling to perform colonoscopy. METHODS: This is a pros...AIM: To assess the feasibility, accuracy and acceptability of PillCam Colon 2 in detection of significant lesions in colorectal cancer risk patients, unable or unwilling to perform colonoscopy. METHODS: This is a prospective, single center study using the second generation of PillCam Colon capsule. In all patients the readers were instructed to review the entire colon capsule endoscopy(CCE) examination using Rapid 7 software and additionally to note significant extra-colonic findings. Colonic significant findings were described according to European Society of Gastrointestinal Endoscopy guidelines. CCE procedure completion rate, level of bowel preparation and rate of adverse events were assessed. RESULTS: A total of 70 patients at risk of colorectal cancer were enrolled in the study. In three patients the procedure failed because the capsule was not functioning when entered the colon. PillCam Colon 2 showed positive findings in 23(34%, 95%CI: 21.6%-44.1%) of the remaining 67 patients. Six patients were diagnosedwith tumors: 4 with colon cancers, 1 with gastric cancer and 1 with a small bowel cancer. The capsule findings were confirmed after surgery in all these patients. The capsule excretion rate in twelve hours was 77% with 54 patients having a complete examination. The rectum was not explored during CCE procedure, in 16 patients(23%, 95%CI: 13.7%-34.1%). Every patient accepted CCE as an alternative exploration tool and 65/70(93%) agreed to have another future control by CCE. No complications were reported during or after CCE examination. CONCLUSION: PillCam Colon 2 capsule was effective in detecting significant lesions and might be considered an adequate alternative diagnostic tool in patients unable or unwilling to undergo colonoscopy.展开更多
文摘This paper examines the phenomenon of sociocultural transfer and its motivating factors within the realization patterns of speech act refusal by Chinese EFL learners. EFL refusal data were collected using a written data collection test (DCT), which was designed and then followed by semi-structured interviews. Using semantic formulas as units of analysis, EFL refusal responses were compared with similar data elicited from native speakers of English. The results show two areas in which sociocultural transfer is existent in EFL learners' speech: options of selecting semantic formulas and content of semantic formulas. Each was found to reflect cultural values transferred from Chinese to English. Furthermore, based on the interview data, it was found that learners' social system and political factors, traditional socio-psychological ideology and economy possibly motivate sociocultural transfer.
基金This research was supported by the National Natural Science Fund of China(No.71873H9)the Ministry of Education Social Science Fund(No.19JHQ060)Zhejiang University-IFPRI Center for International Development Studies.
文摘Pandemic outbreaks disrupt agricultural trade.The possible strengthening of import barriers to products from countries at the epicenter of a pandemic by their trade partners could aggravate this situation.This paper examines the responses of the US Food and Drug Administration(FDA),import refusals,and subsequent trade impacts on the agricultural exports from the developing countries that were the epicenters of four pandemics in the past two decades.Using monthly data for the period 2002-2020,we find increased import refusals and amplified trade-impeding impacts on agricultural exports during pandemic outbreaks.Increased import refusals and the amplification of the trade-impeding effect of import refusals were especially large when China was the epicenter.We further examine possible differences in these results across products and FDA inspection methods,and the main conclusions remain robust.This paper offers a better understanding of the economic outcomes of pandemic outbreaks and provides policy suggestions for China.
基金funded by the National Natural Science Foundation of China (Grant No. 62471048)Open Fund Project of Beijing Key Laboratory of High Dynamic Navigation TechnologyKey Laboratory Fund Project of Modern Measurement and Control Technology, Ministry of Education
文摘In complex environments such as high dynamics and weak signals,a satellite signal compensation method based on prefabricated trajectory assistance and an improved adaptive Kalman filter is proposed for a 155 mm differential rotating rear-body control-guided projectile to address the situation of satellite signal flickering and loss in projectile navigation systems due to environmental limitations.First,establish the system state and measurement equation when receiving satellite signals normally.Second,a seven-degree-of-freedom external ballistic model is constructed,and the ideal trajectory output from the ballistic model is used to provide the virtual motion state of the projectile,which is input into a filter as a substitute observation when satellite signals are lost.Finally,an adaptive Kalman filter(AKF)is designed,the proposed adaptive Kalman filter can accurately adjust the estimation error covariance matrix and Kalman gain in real-time based on information covariance mismatch.The simulation results show that compared to the classical Kalman filter,it can reduce the average positioning error by more than 38.21%in the case of short-term and full-range loss of satellite signals,providing a new idea for the integrated navigation of projectiles with incomplete information under the condition of satellite signal loss.
文摘This paper is to present a typology of refusal strategies which may be employed in the analysis of refusal performance from a discourse approach.Some previous research carried out is reviewed in order to classify non-native speakers' production of this speech act.Then,the suggested taxonomy will be described in a systematized way from an interlanguage pragmatic perspective and within a conversational analysis framework.Finally,it is emphasized that effective communicative competence plays an important role in the production of this face-threatening speech act of refusing.
基金The National Natural Science Foundation of China(No.51476032)
文摘A three-dimensional numerical model verified by previous experimental data is developed to simulate the fluidized bed gasification of refuse derived fuel （RDF）. The CaO dechlorination model obtained by the thermal gravity analysis （TGA） is coupled to investigate the process of CaO dechlorination. An Eulerian-Eulerian method is adopted to simulate the gas-solid flow and self-developed chemical reaction modules are used to simulate chemical reactions. Flow patterns, gasification results and dechlorination efficiency are obtained by numerical simulation. Meanwhile, simulations are performed to evaluate the effects of Ca/Cl molar ratio and temperature on dechlorination efficiency. The simulation results show that the presence of bubbles in the gasifier lowers the CaO dechlorination efficiency. Increasing the Ca/Cl molar ratio can enhance the dechlorination efficiency. However, with the temperature increasing, the dechlorination efficiency increases initially and then decreases. The optimal Ca/Cl molar ratio is in the range of 3. 0 to 3. 5 and the optimal temperature is 923K.
文摘Edward Hall offers us an effective means of examining cultural similarities and differences,that is the classification of high-context and low-context culture.The paper attempts to analyze a case of a Chinese refusal from the perspective of highcontext and low-context communication and explores the differences between the two types of communication.
基金Supported by the government of the Republic of Zambia(GRZ) through Ministry of Health(budget support)United States Government(USG)through USAID and CDC Zambia,Grant U2GPS001792
文摘Objective: To assess the prevalence of HIV infection, to highlight HIV-testing refusal rates among participants in a population-based tuberculosis survey and to assess the implication for programme implementation.Methods: This cross-sectional study on the characteristics of participants who refused HIV testing was conducted in a national survey in Zambia. All eligible participants were aged above 15 years and included in the analysis.Results: Out of the 44 791 tuberculosis survey participants, 14 164(31.6%) refused to participate in HIV testing. The unemployed, rural dwellers, married, and those aged 15-24 years were associated with higher refusal rates.Conclusions: Strategies to improve HIV testing acceptance are necessary. Qualitative research is recommended to understand the reasons for testing refusals so that remedial interventions can be implemented.
文摘The given article deals with the development of analytical model of request service process by multichannel technical system with unreliable, repaired and reconfigured service facilities. It is assumed that the system is functioning in service mode of random length random request flows. The system considers the existence of time redundancy for afterservice of calls, the service of which is interrupted with refusal, non-depreciating the performed part of the task. Special probability functions are introduced which on the basis of probability reasoning allow to make the systems of integral equations describing the dynamics of request service process.
文摘Requests and requesting language have been a popular topic for researchers from a wide range of fields including linguistic philosophy,pragmatics,social-pragmatics,and discourse analysis since 1960s.Requesting is a dynamic process which is the combination of requests and pre-requests,as well as request negotiations.By now,studies mostly focused on the study of how request was initiated and what were the factors lying behind specific choice of one request form over others,and how request-makers pursued their demands when grants were not given as expected.However,limited studies have been published about the development of the strategies children took to avoid predictable refusals.This paper aims to make a contribution to this topic by conducting a longitudinal study lasting for approximately one year with a four-year-old Chinese girl as the subject.By contrasting and comparing the subject’s natural linguistic performance,the author tried to reveal the developmental procedure,and profound cognitive and cultural factors.
文摘The present study analyzes ten English refusal letters of two subcategories based on Swales' genre analysis model and finds that difference exists in the generic features of the two subcategorized types. Teachers should reveal the underlying rationale behind linguistic features of a specific genre so that students can not only identify genre but also apply it appropriately.
文摘This paper tries to analyze Philip Larkin's poem"High Window"from a deconstructive perspective. It is to show that in the poem the key words/signifiers are always under erasure, and thus the chain of signification is endless since the poem is self-deconstructing. Then, the paper argues that the linguistic features of the poem paradoxically meaningful in the sense that it reflects the poet's skepticism and anxiety.
基金supported by the Natural Science Foundation of Shanghai of China,No.17ZR1425800(to KYL)the Shanghai Pudong District Health Bureau of China,No.PDZX2017-25(to KYL)
文摘Appropriate autophagy has protective effects on ischemic nerve tissue,while excessive autophagy may cause cell death.The inflammatory response plays an important role in the survival of nerve cells and the recovery of neural tissue after ischemia.Many studies have found an interaction between autophagy and inflammation in the pathogenesis of ischemic stroke.This study outlines recent advances regarding the role of autophagy in the post-stroke inflammatory response as follows.(1)Autophagy inhibits inflammatory responses caused by ischemic stimulation through mTOR,the AMPK pathway,and inhibition of inflammasome activation.(2)Activation of inflammation triggers the formation of autophagosomes,and the upregulation of autophagy levels is marked by a significant increase in the autophagy-forming markers LC3-II and Beclin-1.Lipopolysaccharide stimulates microglia and inhibits ULK1 activity by direct phosphorylation of p38 MAPK,reducing the flux and autophagy level,thereby inducing inflammatory activity.(3)By blocking the activation of autophagy,the activation of inflammasomes can alleviate cerebral ischemic injury.Autophagy can also regulate the phenotypic alternation of microglia through the nuclear factor-κB pathway,which is beneficial to the recovery of neural tissue after ischemia.Studies have shown that some drugs such as resveratrol can exert neuroprotective effects by regulating the autophagy-inflammatory pathway.These studies suggest that the autophagy-inflammatory pathway may provide a new direction for the treatment of ischemic stroke.
基金TheNationalNaturalScienceFoundationofChina (No .2 97770 19)theExcellentYouthFoundationofChinaEducationMinistry
文摘Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their long term stabilization process. In this paper, this process is also referred to as mineralization process and the resultant stabilized refuse referred to as aged refuse. Aged refuse contains a wide spectrum and huge quantity of microorganisms with strong decomposition capability for refractory organic matter present in some wastewater such as leachate. In this study, aged refuse excavated from 2 to 10 years old closed landfill compartments in Shanghai Refuse Landfill is characterized in terms of particulate distribution by screening, total nitrogen, total phosphorus, biodegradable matter. The approaches for redevelopment of both land and aged refuse in the stabilized landfills are proposed.
基金supported by the Ministry of Education of China (No. 305005)the Science and Technology Commission of Shanghai Municipality (No. 05DZ12003).
文摘A field-scale aged refuse （AR） biofilter constructed in Shanghai Refuse Landfill, containing about 7000 m^3 aged refuse inside, was evaluated for its performance in the treatment of landfill leachate. This AR biofilter can be divided into three stages and can manage 50 m^3 landfill leachate per day. The physical, chemical, and biological characteristics of AR were analyzed for evaluating the AR biofilter as leachate treatment host. The results revealed that over 87.8%-96.2% of COD and 96.9%-99.4% of ammonia nitrogen were removed by the three-stage AR biofilter when the infiuent leachate COD and ammonia nitrogen concentration were in the range 5478-10842 mg/L and 811-1582 mg/L, respectively. The final effluent was inodorous and pale yellow with COD and ammonia nitrogen below 267-1020 mg/L and 6-45 mg/L, respectively. The three-stage AR biofilter had efficient nitrification but relative poor denitrification capacity with a total nitrogen （TN） removal of 58%-73%. The external temperature of AR biofilter did not influence the total ammonia nitrogen removal significantly. It was concluded that the scale-up AR biofilter can work very well and can be a promising technology for the treatment of landfill leachate.
基金supported by the National Natural Science Foundation of China (No. 51008322)the Natural Science Foundation Project of Chongqing (No. CSTC 2010BB7300,5309)the State Key Laboratory of Pollution Control and Resource Reuse (No. PCRRF10001)
文摘To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laogang MSW landfills, Shanghai, China. Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity. The maximum specific cell growth rates （μmax= 0.042 hr-1, R2= 0.995） was derived through Boltzmann simulation, and the apparent half-saturation constants （Km（app） = 7.08 mmol/L, R2 = 0.982） was calculated according to Michaelis-Menton hyperbolic model, indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs. By way of adding the strain JTA1 culture, the methane consumption of aged refuse reached 115 mL, almost two times of control experiment. In addition, high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers. At the chloroform concentration of 50 mg/L, the methane-oxidation rate of bio-cover reached 0.114 mL/（day.g）, much higher than the highest rate, 0.0135 mL/（day.g）, of reported bio-covers. In conclusion, strain JTA1 opens up a new possibility for environmental biotechnology, such as soil or landfills bioremediation and wastewater decontamination.
文摘Approximately 7000 m^3 of aged refuse （AR） with a placement of over eight years was excavated from Shanghai Refuse Landfill, the largest landfill in China, and used for the construction of a two-stage bioreactor （AR biofilter） media for the biological treatment of 100 m3 of refuse landfill leachate. It was found that over 64% of COD, 96.9%-99.8% of NH4^＋-N, and 95.8%-99.8% of BOD5 could be removed by the AR biofilter, when the leachate with initial COD, BOD5, and NH4^＋-N concentrations were 986-4128 mg/L, 264--959 mg/L,m and 538-1583 mg/L, respectively. The corresponding concentrations in the effluent were reduced to below 30（000 mg/L, 2-12 mg/L, and 10-20 mg/L, respectively. The effluent was clear and pale yellow with suspended solid below 150 mg/L and color below 150 Pt/Co degree. Meanwhile, the total nitrogen removal was only 49%-63%, indicating a relative poor denitrification capacity of AR biofilter. The effluent pH was neutral and the population of Escherichia coli was less than 10^-1 CFU/mL. Hence, it was considered that the demonstration project can work well for the effective treatment of leachate.
基金supported by the special action project "Saving energy and reducing emission" of Chongqing City( No.CSTC2010AA7060)the National Natural Science Foundation of China (No.21176273)
文摘Biologically-treated municipal solid waste （MSW） leachate still contains many kinds of bit-recalcitrant organic matter. A new plate and frame electrochemical reactor was designed to treat these materials under flow conditions. In the electrochemical oxidation process, NH3 and color could be easily removed by means of electro-generated chlorinefaypochlorite within 20 min. The effects of major process parameters on the removal of organic pollutants were investigated systematically. Under experimental conditions, the optimum operation parameters were current density of 65 mA/cm^2, flow velocity of 2.6 cm/sec in electrode gap, and initial chloride ion concentration of 5000 mg/L. The COD in the leachate could be reduced below 100 mg/L after 1 hr of treatment. The kinetics and mechanism of COD removal were investigated by simultaneously monitoring the COD change and chlorine/hypochlorite production. The kinetics of COD removal exhibited a two-stage kinetic model, and the decrease of electro-generated chlorine/hypochlorite production was the major mechanism for the slowing down of the COD removal rate in the second stage. The narrowing of the electrode gap is beneficial for COD removal and energy consumption.
文摘AIM: To assess the feasibility, accuracy and acceptability of PillCam Colon 2 in detection of significant lesions in colorectal cancer risk patients, unable or unwilling to perform colonoscopy. METHODS: This is a prospective, single center study using the second generation of PillCam Colon capsule. In all patients the readers were instructed to review the entire colon capsule endoscopy(CCE) examination using Rapid 7 software and additionally to note significant extra-colonic findings. Colonic significant findings were described according to European Society of Gastrointestinal Endoscopy guidelines. CCE procedure completion rate, level of bowel preparation and rate of adverse events were assessed. RESULTS: A total of 70 patients at risk of colorectal cancer were enrolled in the study. In three patients the procedure failed because the capsule was not functioning when entered the colon. PillCam Colon 2 showed positive findings in 23(34%, 95%CI: 21.6%-44.1%) of the remaining 67 patients. Six patients were diagnosedwith tumors: 4 with colon cancers, 1 with gastric cancer and 1 with a small bowel cancer. The capsule findings were confirmed after surgery in all these patients. The capsule excretion rate in twelve hours was 77% with 54 patients having a complete examination. The rectum was not explored during CCE procedure, in 16 patients(23%, 95%CI: 13.7%-34.1%). Every patient accepted CCE as an alternative exploration tool and 65/70(93%) agreed to have another future control by CCE. No complications were reported during or after CCE examination. CONCLUSION: PillCam Colon 2 capsule was effective in detecting significant lesions and might be considered an adequate alternative diagnostic tool in patients unable or unwilling to undergo colonoscopy.
