Artificial Intelligence(AI),as a strategic technology leading the new round of scientific and technological revolution and industrial transformation,is reshaping the global power dynamics.Major countries are accelerat...Artificial Intelligence(AI),as a strategic technology leading the new round of scientific and technological revolution and industrial transformation,is reshaping the global power dynamics.Major countries are accelerating their strategic deployment around technological innovation,standard-setting,and rule-building,making technology increasingly intertwined with geopolitics.Since the U.S.released Preparing for the Future of Artificial Intelligence in 2016,it has integrated AI into its national strategic system and continuously upgraded it,aiming to maintain its dominance in the global competition.Meanwhile,the internal and external tensions of the U.S.AI strategy have become increasingly prominent,profoundly influencing its global strategy and future trajectory.展开更多
In this research,microbiologically induced corrosion(MIC)performance of magnesium in tryptic soy broth with S.aureus or E.coli were systematically explored.The results showed that magnesium in biotic solution presente...In this research,microbiologically induced corrosion(MIC)performance of magnesium in tryptic soy broth with S.aureus or E.coli were systematically explored.The results showed that magnesium in biotic solution presented higher mass loss,thicker degradation product layer and more severe pitting corrosion compared to abiotic solution after 24 h of immersion.Electrochemical measurements including EIS spectra and polarization curve further suggested that the corrosion rate of Mg in biotic solution increased during the early stage owing to the decrease of p H,which was originated from the consumption of glucose and the resulting accumulation of acidic metabolites.However,corrosion rate subsequently decreased because of the reduction of acidic metabolites and production of alkaline compound as well as the corrosion protection provided by the corrosion product and biofilm.Moreover,the corrosion rate of magnesium in high concentration of S.aureus and E.coli solution was larger than that in low concentration of S.aureus and E.coli solution,respectively during the initial stage,but subsequently presented a reverse variation.In addition,more severe corrosion of magnesium was observed in S.aureus solution in comparison with E.coli solution.These results suggested that the MIC performance of magnesium was closely related to the concentration and species of bacteria.展开更多
Ciprofloxacin is a second-generation of fluoroquinolone,broad-spectrum antibiotic with bactericidal activity against Gram-positive and Gram-negative organisms.It is one of the most widely used antibiotics,because of i...Ciprofloxacin is a second-generation of fluoroquinolone,broad-spectrum antibiotic with bactericidal activity against Gram-positive and Gram-negative organisms.It is one of the most widely used antibiotics,because of its efficacy,safety,and relatively low cost.Ascorbic acid(vitamin C)is water-soluble monosaccharide antioxidant;it is essentially required by the body for its various biochemical and physiological processes.S.aureus is Gram-positive cocci;widely distributed in the environment,it is a member of the normal flora of the body.S.aureus is not always pathogenic;it is a common cause of skin infections including abscesses,respiratory infections such as sinusitis,and food poisoning.E.coli is Gram-negative bacteria,found in the environment,foods,and intestines.Most E.coli strains are harmless;it is part of the normal microbiota of the gut.However,some serotypes of E.coli cause serious food poisoning in their hosts;it can cause diarrhea,while others cause urinary tract infections,respiratory illness and pneumonia,and other illnesses.Method:Cup cut diffusion method was applied.Experiment I:is carried out to choose the concentration of vitamin C to be used in experiment II.The negative control is normal saline,added in cup in each plate,vitamin C(100 mg/mL,200 mg/mL,400 mg/mL)was added,the volume in each cup was 100μL.Experiment II:Eight groups of treatments were applied.The first is the negative control(1%normal saline),the second group is the positive control of vitamin C(200 mg/mL).The third,fourth and fifth groups are ciprofloxacin with different concentrations(10 mg/mL,20 mg/mL,40 mg/mL);the sixth,seventh and eighth are the combination of vitamin C with each concentration of ciprofloxacin(10 mg/mL,20 mg/mL,40 mg/mL).Each group includes six petri dishes.Bacterial plates were incubated at 37 oC for 24 h and 48 h.Zone of inhibition is measured in mm.Results and conclusion:Ciprofloxacin produces dose dependent increase in zone of inhibition of S.aureus and E.coli growth,after 24 and 48 hours incubation.While vitamin C in the concentration used produced inhibitory effect on the growth of S.aureus and E.coli,after 24 hours incubation,vitamin C effect was not changed after 48 hours incubation.After 24 hours incubation,vitamin C potentiated the effect of ciprofloxacin at low concentration(10 mg/mL);while vitamin C antagonized the effect of ciprofloxacin at higher concentrations(20 and 40 mg/mL)on S.aureus growth.In the same time,ciprofloxacin antagonized the inhibitory effect of vitamin C on S.aureus growth.After 48 hours incubation,S.aureus produced resistance against ciprofloxacin alone,and that combined with vitamin C compared to zone of inhibition after 24 hours.Ciprofloxacin produced dose dependent inhibition of E.coli growth after incubation for 24 and 48 hours.Vitamin C potentiated the inhibitory effect induced by ciprofloxacin(additive effect).The inhibitory effect of ciprofloxacin,vitamin C and the combination was not changed after 48 hours compared to 24 hours.展开更多
This text combines authors＇ visits and examinations on the spot of Silicon Valley of U.S.A. and Park of Singapore, after analyzing the Park development experience of U.S.A. and Singapore, elucidates ＂three culture e...This text combines authors＇ visits and examinations on the spot of Silicon Valley of U.S.A. and Park of Singapore, after analyzing the Park development experience of U.S.A. and Singapore, elucidates ＂three culture effects＂ of Park development in terms of cultural system emphatically, then proposes some suggestions of cultural innovation in the Park of China.展开更多
A concert by the China National Traditional Orchestra(CNTO)held in the northeast U.S.state of New Jersey on January 29,enthralled thousands of spectators with its music and performance.
In recent years,the political scene in major Western powers has undergone afundamental change in response to the fluid international situation:in the U-nited States,Bill Clinton was elected President in 1992 breaking ...In recent years,the political scene in major Western powers has undergone afundamental change in response to the fluid international situation:in the U-nited States,Bill Clinton was elected President in 1992 breaking Republican controlover White House;while on West European political stage,right-wing ruling pari-ties gave place to the left one after another.Currently,13 out of 15 EU memberstates,except Spain and Ireland,have a government run by left parties or展开更多
A 33-member performing group from Zhejiang Acrobatic Troupe went to the U.S.A on May 6, 2006. During their 11-day trip, they at- tended“06 Zhejiang Week”in New York,“Zhejiang Cultral Week”in Los Angeles and“Asia ...A 33-member performing group from Zhejiang Acrobatic Troupe went to the U.S.A on May 6, 2006. During their 11-day trip, they at- tended“06 Zhejiang Week”in New York,“Zhejiang Cultral Week”in Los Angeles and“Asia Arts Festival”展开更多
文摘Artificial Intelligence(AI),as a strategic technology leading the new round of scientific and technological revolution and industrial transformation,is reshaping the global power dynamics.Major countries are accelerating their strategic deployment around technological innovation,standard-setting,and rule-building,making technology increasingly intertwined with geopolitics.Since the U.S.released Preparing for the Future of Artificial Intelligence in 2016,it has integrated AI into its national strategic system and continuously upgraded it,aiming to maintain its dominance in the global competition.Meanwhile,the internal and external tensions of the U.S.AI strategy have become increasingly prominent,profoundly influencing its global strategy and future trajectory.
基金the Science and Technology Innovation Commission of Shenzhen(Nos.JCYJ20210324120009026,JCYJ20210324102013036,JCYJ20210324101809026,and JCYJ20200109114620793)the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110631)+2 种基金the SIAT Innovation Program for Excellent Young Researchers(No.E1G052)the National Natural Science Foundation of China(Nos.31870956 and U2001221)the Frontier Science Key Research Programs of CAS(No.QYZDB-SSWJSC030)for financially supporting this study。
文摘In this research,microbiologically induced corrosion(MIC)performance of magnesium in tryptic soy broth with S.aureus or E.coli were systematically explored.The results showed that magnesium in biotic solution presented higher mass loss,thicker degradation product layer and more severe pitting corrosion compared to abiotic solution after 24 h of immersion.Electrochemical measurements including EIS spectra and polarization curve further suggested that the corrosion rate of Mg in biotic solution increased during the early stage owing to the decrease of p H,which was originated from the consumption of glucose and the resulting accumulation of acidic metabolites.However,corrosion rate subsequently decreased because of the reduction of acidic metabolites and production of alkaline compound as well as the corrosion protection provided by the corrosion product and biofilm.Moreover,the corrosion rate of magnesium in high concentration of S.aureus and E.coli solution was larger than that in low concentration of S.aureus and E.coli solution,respectively during the initial stage,but subsequently presented a reverse variation.In addition,more severe corrosion of magnesium was observed in S.aureus solution in comparison with E.coli solution.These results suggested that the MIC performance of magnesium was closely related to the concentration and species of bacteria.
文摘Ciprofloxacin is a second-generation of fluoroquinolone,broad-spectrum antibiotic with bactericidal activity against Gram-positive and Gram-negative organisms.It is one of the most widely used antibiotics,because of its efficacy,safety,and relatively low cost.Ascorbic acid(vitamin C)is water-soluble monosaccharide antioxidant;it is essentially required by the body for its various biochemical and physiological processes.S.aureus is Gram-positive cocci;widely distributed in the environment,it is a member of the normal flora of the body.S.aureus is not always pathogenic;it is a common cause of skin infections including abscesses,respiratory infections such as sinusitis,and food poisoning.E.coli is Gram-negative bacteria,found in the environment,foods,and intestines.Most E.coli strains are harmless;it is part of the normal microbiota of the gut.However,some serotypes of E.coli cause serious food poisoning in their hosts;it can cause diarrhea,while others cause urinary tract infections,respiratory illness and pneumonia,and other illnesses.Method:Cup cut diffusion method was applied.Experiment I:is carried out to choose the concentration of vitamin C to be used in experiment II.The negative control is normal saline,added in cup in each plate,vitamin C(100 mg/mL,200 mg/mL,400 mg/mL)was added,the volume in each cup was 100μL.Experiment II:Eight groups of treatments were applied.The first is the negative control(1%normal saline),the second group is the positive control of vitamin C(200 mg/mL).The third,fourth and fifth groups are ciprofloxacin with different concentrations(10 mg/mL,20 mg/mL,40 mg/mL);the sixth,seventh and eighth are the combination of vitamin C with each concentration of ciprofloxacin(10 mg/mL,20 mg/mL,40 mg/mL).Each group includes six petri dishes.Bacterial plates were incubated at 37 oC for 24 h and 48 h.Zone of inhibition is measured in mm.Results and conclusion:Ciprofloxacin produces dose dependent increase in zone of inhibition of S.aureus and E.coli growth,after 24 and 48 hours incubation.While vitamin C in the concentration used produced inhibitory effect on the growth of S.aureus and E.coli,after 24 hours incubation,vitamin C effect was not changed after 48 hours incubation.After 24 hours incubation,vitamin C potentiated the effect of ciprofloxacin at low concentration(10 mg/mL);while vitamin C antagonized the effect of ciprofloxacin at higher concentrations(20 and 40 mg/mL)on S.aureus growth.In the same time,ciprofloxacin antagonized the inhibitory effect of vitamin C on S.aureus growth.After 48 hours incubation,S.aureus produced resistance against ciprofloxacin alone,and that combined with vitamin C compared to zone of inhibition after 24 hours.Ciprofloxacin produced dose dependent inhibition of E.coli growth after incubation for 24 and 48 hours.Vitamin C potentiated the inhibitory effect induced by ciprofloxacin(additive effect).The inhibitory effect of ciprofloxacin,vitamin C and the combination was not changed after 48 hours compared to 24 hours.
文摘This text combines authors＇ visits and examinations on the spot of Silicon Valley of U.S.A. and Park of Singapore, after analyzing the Park development experience of U.S.A. and Singapore, elucidates ＂three culture effects＂ of Park development in terms of cultural system emphatically, then proposes some suggestions of cultural innovation in the Park of China.
文摘A concert by the China National Traditional Orchestra(CNTO)held in the northeast U.S.state of New Jersey on January 29,enthralled thousands of spectators with its music and performance.
文摘In recent years,the political scene in major Western powers has undergone afundamental change in response to the fluid international situation:in the U-nited States,Bill Clinton was elected President in 1992 breaking Republican controlover White House;while on West European political stage,right-wing ruling pari-ties gave place to the left one after another.Currently,13 out of 15 EU memberstates,except Spain and Ireland,have a government run by left parties or
文摘A 33-member performing group from Zhejiang Acrobatic Troupe went to the U.S.A on May 6, 2006. During their 11-day trip, they at- tended“06 Zhejiang Week”in New York,“Zhejiang Cultral Week”in Los Angeles and“Asia Arts Festival”
