Previous studies showed that 4 D-Var technique used for data assimilation could be modified for weather control. This study demonstrates the ability of 4 D-Var to influence the future path of a tropical cyclone by cal...Previous studies showed that 4 D-Var technique used for data assimilation could be modified for weather control. This study demonstrates the ability of 4 D-Var to influence the future path of a tropical cyclone by calculating perturbations in WRF simulation. Given the background error covariance matrix, the initial field is improved by the vortex dynamic initialization technique. Our results show that 4 D-Var can be applied to control the trajectory of simulated tropical cyclones by producing "optimal" perturbations. In the numerical simulation experiment of Typhoon Mitag in 2019, after this kind of weather control similar to data assimilation, the tropical cyclone moved obviously,and the damaging wind over the coastline weakened. The prediction results after the initial field modified by 4 D-Var have a great change, and the position of the tropical cyclone moved about 0.5° southeastward after assimilation,which misses the southeast coast of China. Moreover, the damaging wind is also weakened. Since the 4 D-Var is premised on the assumption that the model is perfect and does not consider the model error, then the research plan to consider model error and introduce new methods is discussed in the paper.展开更多
Hall thrusters have been widely used in orbit correction and the station-keeping of geostationary satellites due to their high specific impulse, long life, and high reliability. During the operating life of a Hall thr...Hall thrusters have been widely used in orbit correction and the station-keeping of geostationary satellites due to their high specific impulse, long life, and high reliability. During the operating life of a Hall thruster, high-energy ions will bombard the discharge channel and cause serious erosion. As time passes, this sputtering process will change the macroscopic surface morphology of the discharge channel, especially near the exit, thus affecting the performance of the thruster.Therefore, it is necessary to carry out research on the motion of the sputtering products and erosion process of the discharge wall. To better understand the moving characteristics of sputtering products, based on the hybrid particle-in-cell（PIC） numerical method, this paper simulates the different erosion states of the thruster discharge channel in different moments and analyzes the moving process of different particles, such as B atoms and B~＋ ions. In this paper,the main conclusion is that B atoms are mainly produced on both sides of the channel exit, and B~＋ ions are mainly produced in the middle of the channel exit. The ionization rate of B atoms is approximately 1%.展开更多
Load balancing is essential for efficient utilization of resources and enhancing the responsiveness of a computational grid, especially that hosts of services most frequently used, i.e. food, health and nutrition. Var...Load balancing is essential for efficient utilization of resources and enhancing the responsiveness of a computational grid, especially that hosts of services most frequently used, i.e. food, health and nutrition. Various techniques have been developed and applied;each has its own limitations due to the dynamic nature of the grid. Efficient load balancing can be achieved by an effective measure of the node’s/cluster’s utilization. In this paper, as a part of an NSTIP project # 10-INF1381-04 and in order to assess of FAQIH framework ability to support the load balance in a computational grid that hosts of food, health and nutrition inquire services. We detail the design and implementation of a proposed fuzzy-logic-based scheme for dynamic load balancing in grid computing services. The proposed scheme works by using a fuzzy logic inference system which uses some metrics to capture the variability of loads and specifies the state of each node per a cluster. Then, based on the overall nodes’ states, the state of the corresponding cluster will be defined in order to assign the newly arrived inquires such that load balancing among different clusters and nodes is accomplished. Many experiments are conducted to investigate the effectiveness of the proposed fuzzy-logic-based scheme to support the load balance where the results show that the proposed scheme achieves really satisfactory and consistently load balance than of other randomize approaches in grid computing services.展开更多
Background. Cutaneous leishmaniasis is a common disease in Iran, espe cially i n the north-east, central and southern parts of the country. Many treatments h ave been suggested for this disease but none is completely ...Background. Cutaneous leishmaniasis is a common disease in Iran, espe cially i n the north-east, central and southern parts of the country. Many treatments h ave been suggested for this disease but none is completely effective and without side-effects such as pain, arthralgia and renal or cardiac complications. Las ers have been used for treatment of several skin diseases since 1970, and CO2 la sers are now being used for treatment of leishmaniasis. In this study, a CO2 las er (Sonic 500 machine)-was used as a source of a continuous CO2 laser wave. Me thods. Atotal of 123 patients (68 female and 55male) with 183 lesions were treat ed with the CO2 laser. The maximum power was 100 W and the pulse width was 0.5- 5 s. For the control group, 110 patients (with 250 lesions) were treated with g lucantime 50 mg/kg/day for 15 days and, after 15 days of rest, this treatment wa s repeated (GlucantimeAmps, 1.5 g in a 50- mLsolution,was used). For follow-u p, the patients were visited 1, 3, 4, 8, 12 and 24 weeks after treatment and any complications, recurrences or other wound characteristics were recorded. In the second group, Finally, all collected data were analyzed statistically. Results. Statistical analysis with the χ 2 test showed that treatment with the CO2 lase r was more effective than treatment with glucantime (P=0.0007). Complications we re also seen less often with the laser treatment than with glucantime and were l imited to the ulcer site. The CO2 laser was more effective in treating cutaneous leishmaniasis than glucantime (1.12 times), had fewer side-effects (4.5% vs . 24% ) and resulted in a shorter healing time (1 month vs. 3 months), and trea tment could be applied in a single session. Conclusions. The results of this and previous studies suggest that cutaneous leishmaniasis can be treated effectivel y with CO2 laser if those providing the treatment are sufficiently experienced. Laser treatment is more cost-effective than other treatments and can be used a s first-line therapy for cutaneous leishmaniasis (wet and dry types).展开更多
Background: Warts occur commonly in humans. Destructive modalities are generally the first physician- administered therapy. Other treatment options include immunotherapy. Intralesionalimmunotherapyusingmumps,Candida,o...Background: Warts occur commonly in humans. Destructive modalities are generally the first physician- administered therapy. Other treatment options include immunotherapy. Intralesionalimmunotherapyusingmumps,Candida,orTrichophyton skin test antigens has proved efficacy in the treatment of warts. Objectives: To determine rates of wart resolution in response to injection of antigen alone, antigen plus interferon alfa- 2b, interferon alfa- 2b alone, and normal saline; and to compare response according to viral type, major histocompatibility complex antigens, and peripheral blood mononuclear cell proliferation to autologous human papillomavirus antigen before and after injection. Design: Randomized, single- blinded, placebo- controlled, clinical trial. Setting: Medical school- based dermatology department. Patients: Two hundred thirty- three patients clinically diagnosed as having 1 or more warts. Main Outcome Measure: Clinical resolution of warts in response to intralesional immunotherapy. Results: Responders were observed in all treatment arms, but were significantly more likely to have received antigen (P < .001). Resolution of distant untreated warts was observed, and was significantly more likely in subjects receiving antigen (P < .001). Interferon did not significantly enhance the response rate (P=.20) and did not differ from normal saline (P=.65). No viral type or major histocompatibility complex antigen correlated with response or lack of response (P > .99 and P=.86, respectively). A positive peripheral blood mononuclear cell proliferation assay result (2 times pretreatment levels) was significantly more likely among responders (P=.002). While there was no significant difference in response based on sex (P=.56), older subjects (>40 years) were less likely to respond (P=.01). Conclusions: Intralesional immunotherapy using injection of Candida, mumps, or Trichophyton skin test antigens is an effective treatment for warts, as indicated by significantly higher response rates and distant response rates in subjects receiving antigen. Viral type and major histocompatibility complex antigens did not seem to influence treatment response. Response is accompanied by proliferation of peripheral blood mononuclear cells to human papillomavirus antigens, suggesting that a human papilloma- virus- directed cell- mediated immune response plays a role in wart resolution.展开更多
Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predi...Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predicted at high temperature. The temperature dependence and frequency dependence of dielectric constant and dielectric loss were discussed, respectively. As the result, the data calculated by theoretical dielectric model are in agreement with experimental data.展开更多
The trade war between the USA and China has shocked many across the world.A disruption to the interdependence of the two largest economies seemed unfathomable.However,in an effort to thwart China’s economic practices...The trade war between the USA and China has shocked many across the world.A disruption to the interdependence of the two largest economies seemed unfathomable.However,in an effort to thwart China’s economic practices and boost the US economy,President Trump’s administration levied tariffs on Chinese imports shortly after taking office,moving US foreign economic policy from liberalism,practiced for decades,to protectionism.China has retaliated,and the trade war continues today.With conceptual insights from the nationalism literature,we explore the nationalist roots of the trade war from both the US and Chinese perspectives.In the USA,the Trump administration’s plan to achieve energy autonomy,decrease reliance on foreign resources,and reinvigorate the manufacturing sector has led to protectionist policies,the othering of China,and hence the trade war.Although reluctant to enter the conflict,China has rebuffed the USA,resisting and counterattacking US actions,owing to a long-felt sense of persecution in the global space and an eagerness to participate fully,and lead in some issue areas,in international affairs.The conflict continues into the COVID-19 era,marked by US scapegoating of China and hits to economic performance.Until both sides are convinced they have achieved their goals,or the USA undergoes an administration change,the conflict will likely continue.展开更多
This paper studies Morita duality of semigroup-graded rings, and discusses an equiva, lence between duality functors of graded module category and bigraded bimodules. An important result is obtained： A semigroup bigr...This paper studies Morita duality of semigroup-graded rings, and discusses an equiva, lence between duality functors of graded module category and bigraded bimodules. An important result is obtained： A semigroup bigraded R-A-bimodule Q defines a semigroup graded Morita duality if and only if Q is gr-faithfully balanced and Ref（RQ）, Ref（QA） is closed under graded submodules and graded quotients.展开更多
One of the major concerns regarding currently proposed public blockchain systems relates to the feasible transaction processing rate.It is common for such systems to limit this rate to maintain the required levels of ...One of the major concerns regarding currently proposed public blockchain systems relates to the feasible transaction processing rate.It is common for such systems to limit this rate to maintain the required levels of security and decentralisation.State channels are an approach to overcome this limitation,as they aim to decrease the required on-chain transactions for a given application and thus indirectly increase the capacity(in terms of applications)of public blockchain systems.In the present paper,we propose a state channel design that,through the use of RSA accumulators,operates on a compact state structure.This scheme is optimal for applications whose state includes large sets of elements.The novel state channel design is presented by analysing all state channel operations and how they have to be revised.The security of the design is discussed,while a practical use case scenario regarding the use of the design for an on-chain asset(e.g.,non-fungible tokens)exchange application is also analysed.展开更多
Coconut water(CW)is a popular natural hydration drink in tropical countries.It is rich in essential electrolytes,vitamins,minerals,and bioactive compounds with functional properties.Therefore,this work aimed to evalua...Coconut water(CW)is a popular natural hydration drink in tropical countries.It is rich in essential electrolytes,vitamins,minerals,and bioactive compounds with functional properties.Therefore,this work aimed to evaluate the functional properties(i.e.,antioxidant and anti-aging activities)and to determine selected bioactive compounds in young and mature CW from the four most popular coconut varieties in Malaysia namely,Aromatic Green Dwarf(PDN),Malaysian Yellow Dwarf(MYD),MATAG(MYD×Tagnanan)and MAWA(MYD×West African Tall).Spectrophotometric and liquid chromatography methods were used to quantify the changes in the tested parameters.It is shown that the quantification of selected bioactive compounds and functional activities of CW displayed a mixed pattern at different maturation.Results from antioxidant,anti-aging activities,amino acids profile and bioactive compounds such as gallic acid,catechin,trans-zeatin,and dihydrozeatin were measured to decrease with the coconuts’maturation.Meanwhile,the amount of kinetin,kinetin riboside and trans-zeatin riboside increased with the maturation of the coconuts.Specifically,CW from young MYD showed the highest antioxidant and anti-aging activities and possessed diverse bioactive compounds that could serve as novel sources of natural functional ingredients targeted for skin anti-aging.In addition,the sensory evaluation showed that the taste of young and mature CW is acceptable for consumption with the young PDN,young MYD and mature MYD displaying the highest score.To the best of our knowledge,the present work reported the first attempt to elucidate the inhibitory activities of CW towards elastase and collagenase enzymes.展开更多
基金National Natural Science Foundation of China(41405062, 41775017)。
文摘Previous studies showed that 4 D-Var technique used for data assimilation could be modified for weather control. This study demonstrates the ability of 4 D-Var to influence the future path of a tropical cyclone by calculating perturbations in WRF simulation. Given the background error covariance matrix, the initial field is improved by the vortex dynamic initialization technique. Our results show that 4 D-Var can be applied to control the trajectory of simulated tropical cyclones by producing "optimal" perturbations. In the numerical simulation experiment of Typhoon Mitag in 2019, after this kind of weather control similar to data assimilation, the tropical cyclone moved obviously,and the damaging wind over the coastline weakened. The prediction results after the initial field modified by 4 D-Var have a great change, and the position of the tropical cyclone moved about 0.5° southeastward after assimilation,which misses the southeast coast of China. Moreover, the damaging wind is also weakened. Since the 4 D-Var is premised on the assumption that the model is perfect and does not consider the model error, then the research plan to consider model error and introduce new methods is discussed in the paper.
文摘Hall thrusters have been widely used in orbit correction and the station-keeping of geostationary satellites due to their high specific impulse, long life, and high reliability. During the operating life of a Hall thruster, high-energy ions will bombard the discharge channel and cause serious erosion. As time passes, this sputtering process will change the macroscopic surface morphology of the discharge channel, especially near the exit, thus affecting the performance of the thruster.Therefore, it is necessary to carry out research on the motion of the sputtering products and erosion process of the discharge wall. To better understand the moving characteristics of sputtering products, based on the hybrid particle-in-cell（PIC） numerical method, this paper simulates the different erosion states of the thruster discharge channel in different moments and analyzes the moving process of different particles, such as B atoms and B~＋ ions. In this paper,the main conclusion is that B atoms are mainly produced on both sides of the channel exit, and B~＋ ions are mainly produced in the middle of the channel exit. The ionization rate of B atoms is approximately 1%.
文摘Load balancing is essential for efficient utilization of resources and enhancing the responsiveness of a computational grid, especially that hosts of services most frequently used, i.e. food, health and nutrition. Various techniques have been developed and applied;each has its own limitations due to the dynamic nature of the grid. Efficient load balancing can be achieved by an effective measure of the node’s/cluster’s utilization. In this paper, as a part of an NSTIP project # 10-INF1381-04 and in order to assess of FAQIH framework ability to support the load balance in a computational grid that hosts of food, health and nutrition inquire services. We detail the design and implementation of a proposed fuzzy-logic-based scheme for dynamic load balancing in grid computing services. The proposed scheme works by using a fuzzy logic inference system which uses some metrics to capture the variability of loads and specifies the state of each node per a cluster. Then, based on the overall nodes’ states, the state of the corresponding cluster will be defined in order to assign the newly arrived inquires such that load balancing among different clusters and nodes is accomplished. Many experiments are conducted to investigate the effectiveness of the proposed fuzzy-logic-based scheme to support the load balance where the results show that the proposed scheme achieves really satisfactory and consistently load balance than of other randomize approaches in grid computing services.
文摘Background. Cutaneous leishmaniasis is a common disease in Iran, espe cially i n the north-east, central and southern parts of the country. Many treatments h ave been suggested for this disease but none is completely effective and without side-effects such as pain, arthralgia and renal or cardiac complications. Las ers have been used for treatment of several skin diseases since 1970, and CO2 la sers are now being used for treatment of leishmaniasis. In this study, a CO2 las er (Sonic 500 machine)-was used as a source of a continuous CO2 laser wave. Me thods. Atotal of 123 patients (68 female and 55male) with 183 lesions were treat ed with the CO2 laser. The maximum power was 100 W and the pulse width was 0.5- 5 s. For the control group, 110 patients (with 250 lesions) were treated with g lucantime 50 mg/kg/day for 15 days and, after 15 days of rest, this treatment wa s repeated (GlucantimeAmps, 1.5 g in a 50- mLsolution,was used). For follow-u p, the patients were visited 1, 3, 4, 8, 12 and 24 weeks after treatment and any complications, recurrences or other wound characteristics were recorded. In the second group, Finally, all collected data were analyzed statistically. Results. Statistical analysis with the χ 2 test showed that treatment with the CO2 lase r was more effective than treatment with glucantime (P=0.0007). Complications we re also seen less often with the laser treatment than with glucantime and were l imited to the ulcer site. The CO2 laser was more effective in treating cutaneous leishmaniasis than glucantime (1.12 times), had fewer side-effects (4.5% vs . 24% ) and resulted in a shorter healing time (1 month vs. 3 months), and trea tment could be applied in a single session. Conclusions. The results of this and previous studies suggest that cutaneous leishmaniasis can be treated effectivel y with CO2 laser if those providing the treatment are sufficiently experienced. Laser treatment is more cost-effective than other treatments and can be used a s first-line therapy for cutaneous leishmaniasis (wet and dry types).
文摘Background: Warts occur commonly in humans. Destructive modalities are generally the first physician- administered therapy. Other treatment options include immunotherapy. Intralesionalimmunotherapyusingmumps,Candida,orTrichophyton skin test antigens has proved efficacy in the treatment of warts. Objectives: To determine rates of wart resolution in response to injection of antigen alone, antigen plus interferon alfa- 2b, interferon alfa- 2b alone, and normal saline; and to compare response according to viral type, major histocompatibility complex antigens, and peripheral blood mononuclear cell proliferation to autologous human papillomavirus antigen before and after injection. Design: Randomized, single- blinded, placebo- controlled, clinical trial. Setting: Medical school- based dermatology department. Patients: Two hundred thirty- three patients clinically diagnosed as having 1 or more warts. Main Outcome Measure: Clinical resolution of warts in response to intralesional immunotherapy. Results: Responders were observed in all treatment arms, but were significantly more likely to have received antigen (P < .001). Resolution of distant untreated warts was observed, and was significantly more likely in subjects receiving antigen (P < .001). Interferon did not significantly enhance the response rate (P=.20) and did not differ from normal saline (P=.65). No viral type or major histocompatibility complex antigen correlated with response or lack of response (P > .99 and P=.86, respectively). A positive peripheral blood mononuclear cell proliferation assay result (2 times pretreatment levels) was significantly more likely among responders (P=.002). While there was no significant difference in response based on sex (P=.56), older subjects (>40 years) were less likely to respond (P=.01). Conclusions: Intralesional immunotherapy using injection of Candida, mumps, or Trichophyton skin test antigens is an effective treatment for warts, as indicated by significantly higher response rates and distant response rates in subjects receiving antigen. Viral type and major histocompatibility complex antigens did not seem to influence treatment response. Response is accompanied by proliferation of peripheral blood mononuclear cells to human papillomavirus antigens, suggesting that a human papilloma- virus- directed cell- mediated immune response plays a role in wart resolution.
文摘Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predicted at high temperature. The temperature dependence and frequency dependence of dielectric constant and dielectric loss were discussed, respectively. As the result, the data calculated by theoretical dielectric model are in agreement with experimental data.
文摘The trade war between the USA and China has shocked many across the world.A disruption to the interdependence of the two largest economies seemed unfathomable.However,in an effort to thwart China’s economic practices and boost the US economy,President Trump’s administration levied tariffs on Chinese imports shortly after taking office,moving US foreign economic policy from liberalism,practiced for decades,to protectionism.China has retaliated,and the trade war continues today.With conceptual insights from the nationalism literature,we explore the nationalist roots of the trade war from both the US and Chinese perspectives.In the USA,the Trump administration’s plan to achieve energy autonomy,decrease reliance on foreign resources,and reinvigorate the manufacturing sector has led to protectionist policies,the othering of China,and hence the trade war.Although reluctant to enter the conflict,China has rebuffed the USA,resisting and counterattacking US actions,owing to a long-felt sense of persecution in the global space and an eagerness to participate fully,and lead in some issue areas,in international affairs.The conflict continues into the COVID-19 era,marked by US scapegoating of China and hits to economic performance.Until both sides are convinced they have achieved their goals,or the USA undergoes an administration change,the conflict will likely continue.
基金Foundation item： the National Natural Science Foundation of China （No. 10571043 10671053） the Natural Science Foundation of Hebei Province （No. 102132） and the Fundation of the Education Department of Hebei Province （No. 2004108）.
文摘This paper studies Morita duality of semigroup-graded rings, and discusses an equiva, lence between duality functors of graded module category and bigraded bimodules. An important result is obtained： A semigroup bigraded R-A-bimodule Q defines a semigroup graded Morita duality if and only if Q is gr-faithfully balanced and Ref（RQ）, Ref（QA） is closed under graded submodules and graded quotients.
文摘One of the major concerns regarding currently proposed public blockchain systems relates to the feasible transaction processing rate.It is common for such systems to limit this rate to maintain the required levels of security and decentralisation.State channels are an approach to overcome this limitation,as they aim to decrease the required on-chain transactions for a given application and thus indirectly increase the capacity(in terms of applications)of public blockchain systems.In the present paper,we propose a state channel design that,through the use of RSA accumulators,operates on a compact state structure.This scheme is optimal for applications whose state includes large sets of elements.The novel state channel design is presented by analysing all state channel operations and how they have to be revised.The security of the design is discussed,while a practical use case scenario regarding the use of the design for an on-chain asset(e.g.,non-fungible tokens)exchange application is also analysed.
基金Universiti Putra Malaysia for funding the present work[grant no.:IPM-9595500 and IPS-9688500]financing the first author’s postgraduate studies(Graduate Research Fellowship)MARDI Bagan Datuk Station for supplying the coconuts.
文摘Coconut water(CW)is a popular natural hydration drink in tropical countries.It is rich in essential electrolytes,vitamins,minerals,and bioactive compounds with functional properties.Therefore,this work aimed to evaluate the functional properties(i.e.,antioxidant and anti-aging activities)and to determine selected bioactive compounds in young and mature CW from the four most popular coconut varieties in Malaysia namely,Aromatic Green Dwarf(PDN),Malaysian Yellow Dwarf(MYD),MATAG(MYD×Tagnanan)and MAWA(MYD×West African Tall).Spectrophotometric and liquid chromatography methods were used to quantify the changes in the tested parameters.It is shown that the quantification of selected bioactive compounds and functional activities of CW displayed a mixed pattern at different maturation.Results from antioxidant,anti-aging activities,amino acids profile and bioactive compounds such as gallic acid,catechin,trans-zeatin,and dihydrozeatin were measured to decrease with the coconuts’maturation.Meanwhile,the amount of kinetin,kinetin riboside and trans-zeatin riboside increased with the maturation of the coconuts.Specifically,CW from young MYD showed the highest antioxidant and anti-aging activities and possessed diverse bioactive compounds that could serve as novel sources of natural functional ingredients targeted for skin anti-aging.In addition,the sensory evaluation showed that the taste of young and mature CW is acceptable for consumption with the young PDN,young MYD and mature MYD displaying the highest score.To the best of our knowledge,the present work reported the first attempt to elucidate the inhibitory activities of CW towards elastase and collagenase enzymes.
