Produced water from an oil extraction site in South Kuwait was sampled after primary oil – water separation had been carried out. The produced water was filtered through a mixture of activated charcoal and esterified...Produced water from an oil extraction site in South Kuwait was sampled after primary oil – water separation had been carried out. The produced water was filtered through a mixture of activated charcoal and esterified cellulosic material gained from spent coffee grounds as a tertiary adsorption treatment. The earth-alkaline metal ions and heavy metals were separated from the de-oiled produced water by addition of either sodium or potassium hydroxide in the presence of carbon dioxide or by direct addition of solid sodium carbonate. The resulting filtrate gave salt of industrial purity upon selective crystallization on evaporation.展开更多
Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline ...Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline metal ions, specifically calcium ions, of the de-oiled PW were removed by precipitation with sodium carbonate to give access to pure sodium chloride as industrial salt from the remaining PW. While the purity of the precipitated calcium carbonate (CaCO3) depends on the precipitation conditions, CaCO3 of up to 95.48% purity can be obtained, which makes it a salable product. The precipitation of CaCO3 decreases the amount of calcium ions in PW from 11,300 ppm to 84 ppm.展开更多
BACKGROUND Inflammation-related markers including neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),monocyte-to-lymphocyte ratio(MLR),systemic immune-inflammation index(SII),systemic inflammation r...BACKGROUND Inflammation-related markers including neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),monocyte-to-lymphocyte ratio(MLR),systemic immune-inflammation index(SII),systemic inflammation response index(SIRI)and prognostic nutritional index(PNI)could reflect tumor immune microenvironment and predict prognosis of cancers.However,it had not been explored in alpha-fetoprotein(AFP)producing gastric cancer(GC).AIM To determine the predictive value of inflammation-related peripheral blood markers including as NLR,PLR,MLR,SII,SIRI and PNI in the prognosis of AFPproducing GC(AFPGC).Besides,this study would also compare the differences in tumor immune microenvironment,clinical characteristics and prognosis between AFPGC and AFP-GC patients to improve the understanding of this disease.METHODS 573 patients enrolled were retrospectively studied.They were divided into AFP+group(AFP≥20 ng/mL)and AFP-group(AFP<20 ng/mL),comparing the levels of NLR/PLR/MLR/SII/SIRI/PNI and prognosis.In AFP+group,the impact of NLR/PLR/MLR/SII/SIRI/PNI and their dynamic changes on prognosis were further explored.RESULTS Compared with AFP-patients,AFP+patients had higher NLR/PLR/MLR/SII/-SIRI and lower PNI levels and poorer overall survival(OS).In the AFP+group,mortality was significantly lower in the lower NLR/PLR/MLR/SII/SIRI group and higher PNI group.Moreover,the dynamic increase(NLR/PLR/MLR/SII/-SIRI)or decrease(PNI)was associated with the rise of mortality within 1 year of follow-up.CONCLUSION Compared with AFP-patients,the level of inflammation-related peripheral blood markers significantly increased in AFP+patients,which was correlated with OS of AFP+patients.Also,the gradual increase of SII and SIRI was associated with the risk of death within one year in AFP+patients.AFPGC should be considered as a separate type and distinguished from AFP-GC because of the difference in tumor immune microenvironment.It requires basic experiments and large clinical samples in the future.展开更多
Artificial intelligence is increasingly entering everyday healthcare.Large language model(LLM)systems such as Chat Generative Pre-trained Transformer(ChatGPT)have become potentially accessible to everyone,including pa...Artificial intelligence is increasingly entering everyday healthcare.Large language model(LLM)systems such as Chat Generative Pre-trained Transformer(ChatGPT)have become potentially accessible to everyone,including patients with inflammatory bowel diseases(IBD).However,significant ethical issues and pitfalls exist in innovative LLM tools.The hype generated by such systems may lead to unweighted patient trust in these systems.Therefore,it is necessary to understand whether LLMs(trendy ones,such as ChatGPT)can produce plausible medical information(MI)for patients.This review examined ChatGPT’s potential to provide MI regarding questions commonly addressed by patients with IBD to their gastroenterologists.From the review of the outputs provided by ChatGPT,this tool showed some attractive potential while having significant limitations in updating and detailing information and providing inaccurate information in some cases.Further studies and refinement of the ChatGPT,possibly aligning the outputs with the leading medical evidence provided by reliable databases,are needed.展开更多
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ...Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index.展开更多
Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production w...Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production well, the produced fluids commonly contain water. The understanding of this water’s constituents and volumes is vital for the sustainable continuity of production operations, as PW has a number of negative impacts on the infrastructure integrity of the operation. On the other hand, PW can be an alternative source of irrigation water as well as of industrial salt. Interestingly, both the quantity as well as the quality of PW do not remain constant but can vary, both progressively and erratically, even over short periods of time. This paper discusses such a situation of variable PW in an oil and gas operation in the State of Kuwait.展开更多
Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro stud...Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro study had given rise to hopes as to the management of sickle cell disease (SCD) by the use of this plant species. In this paper, the authors aimed to investigate the effect of the aqueous extract of C. pentandra on the production of fetal hemoglobin in SCD patients. The work carried out hemoglobin electrophoresis, for a period of six months, on blood samples from SCD patients who voluntarily undergone routine treatment, based on the medicinal recipe prepared from the bark of the trunk and branches of C. pentandra, in a hospital center of herbal medicines located in Kinshasa. The medicinal recipe called BEAT-SS is a patented product of the hospital center named Centre de Phytothérapie Moderne NIECA. Blood samples from patients under treatment were taken to evaluate the behavior of different forms of hemoglobin (hemoglobin S, hemoglobin F and hemoglobin A2). Agarose gel electrophoresis with integrated reading was used for the separation of the different forms of hemoglobin, as well as their dosage on each sample of sickle blood. A reduction in the proportion of hemoglobin S and an increase in the proportion of fetal hemoglobin were found in all sickle cell patients during the treatment period. This observation could affirm that the management of sickle cell patients using the recipe prepared from the aqueous extract of C. pentandra could increase the level of fetal hemoglobin in these patients.展开更多
Following the reform of the governance of irrigation schemes in Niger, producer cooperatives are encountering real difficulties in ensuring effective and efficient management of irrigation water, infrastructure mainte...Following the reform of the governance of irrigation schemes in Niger, producer cooperatives are encountering real difficulties in ensuring effective and efficient management of irrigation water, infrastructure maintenance and renewal of hydromechanical equipment. The objective of this research is to analyze the issues and challenges of capacity building for Konni producers in the context of AHA management reform in Niger. The methodological approach adopted is based on documentary research and field surveys with all the actors directly concerned with the management of the Konni irrigated perimeter. A total of 448 people were interviewed in all the localities selected. Direct observation and interview are the two field data collection techniques adopted. The data collected was processed and on the basis of the established diagnosis, the training needs were identified. The results show that there are several experiences in terms of training and capacity building of actors in charge of the management of irrigation systems at the Konni AHA level. However, the sustainability of the perimeter is threatened by various crises. The main themes that founded the first training were related to the mobilization, transport and distribution of irrigation water, operation and maintenance, and setting and collection of the fee. In view of the expectations of operators, future issues and challenges, the training modules are increasingly oriented towards social management, the integration of gender in management and environmental impacts. Even if technical progress is possible, the real lever is organizational and requires the professionalization of irrigators. This process requires a new pedagogical approach aimed at irrigators.展开更多
Background: Nowadays, emergence of Carbapenemase-Producing Enterobacterales (CPE) throughout the world has become a public health problem, especially in countries with limited resources. In recent years, CPE of type O...Background: Nowadays, emergence of Carbapenemase-Producing Enterobacterales (CPE) throughout the world has become a public health problem, especially in countries with limited resources. In recent years, CPE of type OXA-48 (Ambler class D) have been identified in Dakar. The aim of this study was to evaluate the phenotypic detection of OXA-48 CPE using a temocillin disc (30 μg). Methodology: A retrospective study was carried out at Medical Biology Laboratory of Pasteur Institute in Dakar on Ertapenem-Resistant Enterobacterales (ERE) strains isolated from 2015 to 2017. These strains were then tested with a 30 μg temocillin disc. Any strain resistant to temocillin (inhibition diameter Results: Forty-one ERE isolated during the study period were tested, of which 34 (82.9%) were OXA-48 based on phenotypic detection using temocillin disc and confirmed by PCR (100%). OXA-48 CPE strains detected were composed of Klebsiella pneumoniae (n = 14;41.2%), Enterobacter cloacae (n = 8;23.5%), Escherichia coli (n = 7, 20.5%), Citrobacter freundii (n = 3;8.8%), Cronobacter sakazakii (n = 1;3%) and Morganella morganii (n = 1;3%). Conclusion: Temocillin resistance has a good positive predictive value for detecting OXA-48 CPE by phenotypic method, confirmed by PCR. Temocillin is therefore a good marker for detection of OXA-48 CPE except Hafnia alvei.展开更多
The Guangdong-Hong Kong-Macao Greater Bay Area is witnessing a surge in economic development,showcasing robust resilience in the co-agglomeration of producer services and manufacturing industries,along with the increa...The Guangdong-Hong Kong-Macao Greater Bay Area is witnessing a surge in economic development,showcasing robust resilience in the co-agglomeration of producer services and manufacturing industries,along with the increasingly evident impact generated by such co-agglomeration.Based on the panel data collected from ten cities in the Guangdong-Hong Kong-Macao Greater Bay Area(excluding Zhaoqing)spanning from 2010 to 2020,we examined the formation mechanism for industrial co-agglomeration in the area from three dimensions:industrial correlation,spatial correlation,and policy guidance.Our analysis was based on a vertical correlation model and was validated using the seemingly unrelated regressions(SUR)method.The findings are as follows:(a)There currently exists no spatial correlation between the producer services and manufacturing sectors in the area,and the correlation between the two remains limited to the former providing specialized services to the latter.(b)Policy guidance has a positive impact on the location selection of industries within the area.By implementing a comprehensive range of favorable policies,local governments can provide effective and scientifically guided recommendations regarding the location of producer services and manufacturing sectors.Therefore,it is crucial to foster the collaboration between producer services and manufacturing sectors and further enhance the co-agglomeration between the two sectors.In addition,the government authorities should also strive to enhance its economic governance capacity,thereby facilitating the formation of such co-agglomeration.展开更多
We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filament...We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma. We examined the performance of the applied scheme, in this context, we implemented the developed model to study selected phenomena in terahertz radiation production, such as the excitation energy and conversion efficiency of the produced THz radiation, in addition to the influence of the pulse chirping on properties of the produced radiation. The obtained numerical results have clarified that the applied HO-FDTD scheme is precisely accurate to solve Maxwell’s equations and sufficiently valid to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma.展开更多
文摘Produced water from an oil extraction site in South Kuwait was sampled after primary oil – water separation had been carried out. The produced water was filtered through a mixture of activated charcoal and esterified cellulosic material gained from spent coffee grounds as a tertiary adsorption treatment. The earth-alkaline metal ions and heavy metals were separated from the de-oiled produced water by addition of either sodium or potassium hydroxide in the presence of carbon dioxide or by direct addition of solid sodium carbonate. The resulting filtrate gave salt of industrial purity upon selective crystallization on evaporation.
文摘Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline metal ions, specifically calcium ions, of the de-oiled PW were removed by precipitation with sodium carbonate to give access to pure sodium chloride as industrial salt from the remaining PW. While the purity of the precipitated calcium carbonate (CaCO3) depends on the precipitation conditions, CaCO3 of up to 95.48% purity can be obtained, which makes it a salable product. The precipitation of CaCO3 decreases the amount of calcium ions in PW from 11,300 ppm to 84 ppm.
文摘BACKGROUND Inflammation-related markers including neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),monocyte-to-lymphocyte ratio(MLR),systemic immune-inflammation index(SII),systemic inflammation response index(SIRI)and prognostic nutritional index(PNI)could reflect tumor immune microenvironment and predict prognosis of cancers.However,it had not been explored in alpha-fetoprotein(AFP)producing gastric cancer(GC).AIM To determine the predictive value of inflammation-related peripheral blood markers including as NLR,PLR,MLR,SII,SIRI and PNI in the prognosis of AFPproducing GC(AFPGC).Besides,this study would also compare the differences in tumor immune microenvironment,clinical characteristics and prognosis between AFPGC and AFP-GC patients to improve the understanding of this disease.METHODS 573 patients enrolled were retrospectively studied.They were divided into AFP+group(AFP≥20 ng/mL)and AFP-group(AFP<20 ng/mL),comparing the levels of NLR/PLR/MLR/SII/SIRI/PNI and prognosis.In AFP+group,the impact of NLR/PLR/MLR/SII/SIRI/PNI and their dynamic changes on prognosis were further explored.RESULTS Compared with AFP-patients,AFP+patients had higher NLR/PLR/MLR/SII/-SIRI and lower PNI levels and poorer overall survival(OS).In the AFP+group,mortality was significantly lower in the lower NLR/PLR/MLR/SII/SIRI group and higher PNI group.Moreover,the dynamic increase(NLR/PLR/MLR/SII/-SIRI)or decrease(PNI)was associated with the rise of mortality within 1 year of follow-up.CONCLUSION Compared with AFP-patients,the level of inflammation-related peripheral blood markers significantly increased in AFP+patients,which was correlated with OS of AFP+patients.Also,the gradual increase of SII and SIRI was associated with the risk of death within one year in AFP+patients.AFPGC should be considered as a separate type and distinguished from AFP-GC because of the difference in tumor immune microenvironment.It requires basic experiments and large clinical samples in the future.
文摘Artificial intelligence is increasingly entering everyday healthcare.Large language model(LLM)systems such as Chat Generative Pre-trained Transformer(ChatGPT)have become potentially accessible to everyone,including patients with inflammatory bowel diseases(IBD).However,significant ethical issues and pitfalls exist in innovative LLM tools.The hype generated by such systems may lead to unweighted patient trust in these systems.Therefore,it is necessary to understand whether LLMs(trendy ones,such as ChatGPT)can produce plausible medical information(MI)for patients.This review examined ChatGPT’s potential to provide MI regarding questions commonly addressed by patients with IBD to their gastroenterologists.From the review of the outputs provided by ChatGPT,this tool showed some attractive potential while having significant limitations in updating and detailing information and providing inaccurate information in some cases.Further studies and refinement of the ChatGPT,possibly aligning the outputs with the leading medical evidence provided by reliable databases,are needed.
基金the Special Project of the National Science Foundation of China(NSFC)“Open Development of China’s Trade and Investment:Basic Patterns,Overall Effects,and the Dual Circulations Paradigm”(Grant No.72141309)NSFC General Project“GVC Restructuring Effect of Emergent Public Health Incidents:Based on the General Equilibrium Model Approach of the Production Networks Structure”(Grant No.72073142)+1 种基金NSFC General Project“China’s Industrialization Towards Mid-and High-End Value Chains:Theoretical Implications,Measurement and Analysis”(Grant No.71873142)the Youth project of The National Social Science Fund of China“Research on the green and low-carbon development path and policy optimization of China’s foreign trade under the goal of‘dual carbon’”(Grant No.22CJY019).
文摘Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index.
文摘Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production well, the produced fluids commonly contain water. The understanding of this water’s constituents and volumes is vital for the sustainable continuity of production operations, as PW has a number of negative impacts on the infrastructure integrity of the operation. On the other hand, PW can be an alternative source of irrigation water as well as of industrial salt. Interestingly, both the quantity as well as the quality of PW do not remain constant but can vary, both progressively and erratically, even over short periods of time. This paper discusses such a situation of variable PW in an oil and gas operation in the State of Kuwait.
文摘Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro study had given rise to hopes as to the management of sickle cell disease (SCD) by the use of this plant species. In this paper, the authors aimed to investigate the effect of the aqueous extract of C. pentandra on the production of fetal hemoglobin in SCD patients. The work carried out hemoglobin electrophoresis, for a period of six months, on blood samples from SCD patients who voluntarily undergone routine treatment, based on the medicinal recipe prepared from the bark of the trunk and branches of C. pentandra, in a hospital center of herbal medicines located in Kinshasa. The medicinal recipe called BEAT-SS is a patented product of the hospital center named Centre de Phytothérapie Moderne NIECA. Blood samples from patients under treatment were taken to evaluate the behavior of different forms of hemoglobin (hemoglobin S, hemoglobin F and hemoglobin A2). Agarose gel electrophoresis with integrated reading was used for the separation of the different forms of hemoglobin, as well as their dosage on each sample of sickle blood. A reduction in the proportion of hemoglobin S and an increase in the proportion of fetal hemoglobin were found in all sickle cell patients during the treatment period. This observation could affirm that the management of sickle cell patients using the recipe prepared from the aqueous extract of C. pentandra could increase the level of fetal hemoglobin in these patients.
文摘Following the reform of the governance of irrigation schemes in Niger, producer cooperatives are encountering real difficulties in ensuring effective and efficient management of irrigation water, infrastructure maintenance and renewal of hydromechanical equipment. The objective of this research is to analyze the issues and challenges of capacity building for Konni producers in the context of AHA management reform in Niger. The methodological approach adopted is based on documentary research and field surveys with all the actors directly concerned with the management of the Konni irrigated perimeter. A total of 448 people were interviewed in all the localities selected. Direct observation and interview are the two field data collection techniques adopted. The data collected was processed and on the basis of the established diagnosis, the training needs were identified. The results show that there are several experiences in terms of training and capacity building of actors in charge of the management of irrigation systems at the Konni AHA level. However, the sustainability of the perimeter is threatened by various crises. The main themes that founded the first training were related to the mobilization, transport and distribution of irrigation water, operation and maintenance, and setting and collection of the fee. In view of the expectations of operators, future issues and challenges, the training modules are increasingly oriented towards social management, the integration of gender in management and environmental impacts. Even if technical progress is possible, the real lever is organizational and requires the professionalization of irrigators. This process requires a new pedagogical approach aimed at irrigators.
文摘Background: Nowadays, emergence of Carbapenemase-Producing Enterobacterales (CPE) throughout the world has become a public health problem, especially in countries with limited resources. In recent years, CPE of type OXA-48 (Ambler class D) have been identified in Dakar. The aim of this study was to evaluate the phenotypic detection of OXA-48 CPE using a temocillin disc (30 μg). Methodology: A retrospective study was carried out at Medical Biology Laboratory of Pasteur Institute in Dakar on Ertapenem-Resistant Enterobacterales (ERE) strains isolated from 2015 to 2017. These strains were then tested with a 30 μg temocillin disc. Any strain resistant to temocillin (inhibition diameter Results: Forty-one ERE isolated during the study period were tested, of which 34 (82.9%) were OXA-48 based on phenotypic detection using temocillin disc and confirmed by PCR (100%). OXA-48 CPE strains detected were composed of Klebsiella pneumoniae (n = 14;41.2%), Enterobacter cloacae (n = 8;23.5%), Escherichia coli (n = 7, 20.5%), Citrobacter freundii (n = 3;8.8%), Cronobacter sakazakii (n = 1;3%) and Morganella morganii (n = 1;3%). Conclusion: Temocillin resistance has a good positive predictive value for detecting OXA-48 CPE by phenotypic method, confirmed by PCR. Temocillin is therefore a good marker for detection of OXA-48 CPE except Hafnia alvei.
基金This paper is funded by the National Social Science Foundation of China entitled“A Study on the Role of Digital Technology in Facilitating the Integration of Modern Services and Advanced Manufacturing Sectors”(21BJY144)Major project supported by the Key Research Base of Humanities and Social Sciences in Universities of the Ministry of Education entitled“An Exploration of the Paths for Promoting High-level Opening Up in Guangdong-Hong Kong-Macao Greater Bay Area and Corresponding Measures”(22JD790056)Key project of Universities in Guangdong Province entitled“Research on Mechanism and Effect of Co-agglomeration of Producer Services and Manufacturing in Guangdong-Hong Kong-Macao Greater Bay Area”(2019WZDXM029).
文摘The Guangdong-Hong Kong-Macao Greater Bay Area is witnessing a surge in economic development,showcasing robust resilience in the co-agglomeration of producer services and manufacturing industries,along with the increasingly evident impact generated by such co-agglomeration.Based on the panel data collected from ten cities in the Guangdong-Hong Kong-Macao Greater Bay Area(excluding Zhaoqing)spanning from 2010 to 2020,we examined the formation mechanism for industrial co-agglomeration in the area from three dimensions:industrial correlation,spatial correlation,and policy guidance.Our analysis was based on a vertical correlation model and was validated using the seemingly unrelated regressions(SUR)method.The findings are as follows:(a)There currently exists no spatial correlation between the producer services and manufacturing sectors in the area,and the correlation between the two remains limited to the former providing specialized services to the latter.(b)Policy guidance has a positive impact on the location selection of industries within the area.By implementing a comprehensive range of favorable policies,local governments can provide effective and scientifically guided recommendations regarding the location of producer services and manufacturing sectors.Therefore,it is crucial to foster the collaboration between producer services and manufacturing sectors and further enhance the co-agglomeration between the two sectors.In addition,the government authorities should also strive to enhance its economic governance capacity,thereby facilitating the formation of such co-agglomeration.
文摘We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma. We examined the performance of the applied scheme, in this context, we implemented the developed model to study selected phenomena in terahertz radiation production, such as the excitation energy and conversion efficiency of the produced THz radiation, in addition to the influence of the pulse chirping on properties of the produced radiation. The obtained numerical results have clarified that the applied HO-FDTD scheme is precisely accurate to solve Maxwell’s equations and sufficiently valid to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma.