AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank...AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank,sham,I/R,and ischemia/reperfusion and drainage(I/R + D) groups(n = 8).All rats were subjected to 60 min ischemia by clamping the superior mesenteric artery,followed by 120 min reperfusion.The rats in the I/R + D group received intestinal lymph drainage for 180 min.In the sham group,the abdominal cavity was opened for 180 min,but the rats received no treatment.The blank group served as a normal and untreated control.A chromogenic limulus assay kit was used for quantita-tive detection of serum endotoxin.The serum concentrations of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β,soluble cell adhesion molecules(sICAM-1),and high mobility group protein box 1(HMGB1) were determined with an enzyme-linked immunosorbent assay kit.Histological evaluations of the intestine,liver,kidney,and lung were performed by hematoxylin and eosin staining and immunohistochemistry.HMGB1 protein expression was assayed by western blot analysis.RESULTS:The serum levels of endotoxin and HMGB1 in the I/R and I/R + D groups were significantly higher than those in the sham group(endotoxin,I/R and I/R + D vs sham:0.033 ± 0.004 EU/mL,0.024 ± 0.003 EU/mL vs 0.017 ± 0.009 EU/mL,respectively,P < 0.05;HMGB1,I/R and I/R + D vs sham:5.473 ± 0.963 EU/mL,4.906 ± 0.552 EU/mL vs 0.476 ± 0.406 EU/mL,respectively,P < 0.05).In addition,endotoxin and HMGB1 were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The serum inflammatory factors IL-6,IL-1β,and sICAM-1 in the I/R and I/R + D groups were significantly higher than those in the sham group(IL-6,I/R and I/R + D vs sham:41.773 ± 9.753 pg/mL,19.204 ± 4.136 pg/mL vs 11.566 ± 2.973 pg/mL,respectively,P < 0.05;IL-1β,I/R and I/R + D vs sham:144.646 ± 29.378 pg/mL,65.829 ± 10.888 pg/mL vs 38.178 ± 7.157 pg/mL,respectively,P < 0.05;sICAM-1,I/R and I/R + D vs sham:97.360 ± 12.714 ng/mL,48.401 ± 6.547 ng/mL vs 33.073 ± 5.957 ng/mL,respectively;P < 0.05).The serum TNF-α in the I/R group were significantly higher than in the sham group(45.863 ± 11.553 pg/mL vs 18.863 ± 6.679 pg/mL,respectively,P < 0.05).These factors were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The HMGB1 immunohistochemical staining results showed no staining or apparent injury in the blank group,and slight staining at the top of the microvillus was detected in the sham group.In the I/R group,both the top of villi and the basement membrane were stained for HMGB1 in most areas,and injury in the I/R + D group was less than that in the I/R group.HMGB1 expression in the liver,kidney,and lung of rats in the I/R + D group was significantly lower than the rats in the I/R group(P < 0.05).CONCLUSION:Lymph drainage could block the "gutlymph" pathway,improve intestinal barrier function,and attenuate distant organ injury incurred by intestinal I/R.展开更多
Nearly lattice-matched InAIGaN/GaN heterostructure is grown on sapphire substrates by pulsed metal organic chemical vapor deposition and excellent high electron mobility transistors are fabricated on this heterostruct...Nearly lattice-matched InAIGaN/GaN heterostructure is grown on sapphire substrates by pulsed metal organic chemical vapor deposition and excellent high electron mobility transistors are fabricated on this heterostructure. The electron mobility is 1668.08cm2/V.s together with a high two-dimensional-electron-gas density of 1.43 × 10^13 cm-2 for the InAlCaN/CaN heterostructure of 2Onto InAlCaN quaternary barrier. High electron mobility transistors with gate dimensions of 1 × 50 μm2 and 4μm source-drain distance exhibit the maximum drain current of 763.91 mA/mm, the maximum extrinsic transconductance of 163.13 mS/mm, and current gain and maximum oscillation cutoff frequencies of 11 GHz and 21 GHz, respectively.展开更多
Ecology seeks to explain species coexistence,but experimental tests of mechanisms for coexistence are difficult to conduct.We synthesized an arbuscular mycorrhizal(AM)fungal community with three fungal species that di...Ecology seeks to explain species coexistence,but experimental tests of mechanisms for coexistence are difficult to conduct.We synthesized an arbuscular mycorrhizal(AM)fungal community with three fungal species that differed in their capacity of foraging for orthophosphate(P)due to differences in soil exploration.We tested whether AM fungal species-specific hyphosphere bacterial assemblages recruited by hyphal exudates enabled differentiation among the fungi in the capacity of mobilizing soil organic P(P_(o)).We found that the less efficient space explorer,Gigaspora margarita,obtained less ^(13)C from the plant,whereas it had higher efficiencies in P_(o)mobilization and alkaline phosphatase(Al Pase)production per unit C than the two efficient space explorers,Rhizophagusintraradices and Funneliformis mosseae.Each AM fungus was associated with a distinct alp gene harboring bacterial assemblage,and the alp gene abundance and P_(o)preference of the microbiome associated with the less efficient space explorer were higher than those of the two other species.We conclude that the traits of AM fungal associated bacterial consortia cause niche differentiation.The trade-off between foraging ability and the ability to recruit effective P_(o)mobilizing microbiomes is a mechanism that allows co-existence of AM fungal species in a single plant root and surrounding soil habitat.展开更多
A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United Stat...A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United States. Twenty-four hour average ambient samples were collected for mass, ions, elements, organic carbon （OC）, elemental carbon （EC）, and trace organic markers analysis. Additional measurements were made to determine diurnal patterns in light-absorbing black carbon （BC） as a marker for combustion sources. Carbonaceous PM sources of on-road gasoline vehicles, on-road diesel vehicles, and off-road diesel engines were characterized with their chemical profiles, as well as fuel-based emission factors, using an In-Plume Sampling System. The Effective Variance Chemical Mass Balance （EV-CMB） source apportionment model was applied to the ambient samples collected, using source profiles developed in this study as well as profiles from other relevant studies. Four main sources contributed to PM2.5 carbon within the Las Vegas Valley： （1） paved road dust, （2） on-road gasoline vehicles, （3） residential wood combustion, and （4） on-road diesel vehicles. CMB estimated that on-road mixed fleet gasoline vehicles are the largest source for OC and EC at all the sites. The contribution of paved road dust to both OC and EC was 5-10% at the four sites. On-road diesel vehicles contribute 22% of the OC and 34% of the EC at a site near the city center, which is located immediately downwind of a major freeway. Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites, These results are consistent with our conceptual model, and the research methodology may be applied to studying other urban areas.展开更多
Multi-component active materials are widely used for organic electronic devices, with every component contributing complementary and synergistic optoelectronic functions. Mixing these components generally leads to low...Multi-component active materials are widely used for organic electronic devices, with every component contributing complementary and synergistic optoelectronic functions. Mixing these components generally leads to lowered crystallinity and weakened charge transport. Therefore, preparing the active materials without substantially disrupting the crystalline lattice is highly desired. Here, we show that crystallization of TIPS-pentacene from solutions in the presence of fluorescent nanofibers of a perylene bisimide derivative （PBI） leads to formation of composites with nanoflber vip incorporated in the crystal host. In spite of the binary composite structure, the TIPS-pentacene maintains the single- crystalline nature. As a result, the incorporation of the PB1 vip introduces additional fluorescence function but does not significantly reduce the charge transport property of the TIPS-pentacene host, exhibiting field-effect mobility as high as 3.34 cm^2 V^-1 s^-1 even though 26.4% of the channel area is taken over by the vip. As such, this work provides a facile approach toward high-performance multifunctional organic electronic materials.展开更多
基金Supported by The National Natural Science Foundation of China,No. 30940069the Natural Sciences Foundation of Beijing,No. 7102127
文摘AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank,sham,I/R,and ischemia/reperfusion and drainage(I/R + D) groups(n = 8).All rats were subjected to 60 min ischemia by clamping the superior mesenteric artery,followed by 120 min reperfusion.The rats in the I/R + D group received intestinal lymph drainage for 180 min.In the sham group,the abdominal cavity was opened for 180 min,but the rats received no treatment.The blank group served as a normal and untreated control.A chromogenic limulus assay kit was used for quantita-tive detection of serum endotoxin.The serum concentrations of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β,soluble cell adhesion molecules(sICAM-1),and high mobility group protein box 1(HMGB1) were determined with an enzyme-linked immunosorbent assay kit.Histological evaluations of the intestine,liver,kidney,and lung were performed by hematoxylin and eosin staining and immunohistochemistry.HMGB1 protein expression was assayed by western blot analysis.RESULTS:The serum levels of endotoxin and HMGB1 in the I/R and I/R + D groups were significantly higher than those in the sham group(endotoxin,I/R and I/R + D vs sham:0.033 ± 0.004 EU/mL,0.024 ± 0.003 EU/mL vs 0.017 ± 0.009 EU/mL,respectively,P < 0.05;HMGB1,I/R and I/R + D vs sham:5.473 ± 0.963 EU/mL,4.906 ± 0.552 EU/mL vs 0.476 ± 0.406 EU/mL,respectively,P < 0.05).In addition,endotoxin and HMGB1 were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The serum inflammatory factors IL-6,IL-1β,and sICAM-1 in the I/R and I/R + D groups were significantly higher than those in the sham group(IL-6,I/R and I/R + D vs sham:41.773 ± 9.753 pg/mL,19.204 ± 4.136 pg/mL vs 11.566 ± 2.973 pg/mL,respectively,P < 0.05;IL-1β,I/R and I/R + D vs sham:144.646 ± 29.378 pg/mL,65.829 ± 10.888 pg/mL vs 38.178 ± 7.157 pg/mL,respectively,P < 0.05;sICAM-1,I/R and I/R + D vs sham:97.360 ± 12.714 ng/mL,48.401 ± 6.547 ng/mL vs 33.073 ± 5.957 ng/mL,respectively;P < 0.05).The serum TNF-α in the I/R group were significantly higher than in the sham group(45.863 ± 11.553 pg/mL vs 18.863 ± 6.679 pg/mL,respectively,P < 0.05).These factors were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The HMGB1 immunohistochemical staining results showed no staining or apparent injury in the blank group,and slight staining at the top of the microvillus was detected in the sham group.In the I/R group,both the top of villi and the basement membrane were stained for HMGB1 in most areas,and injury in the I/R + D group was less than that in the I/R group.HMGB1 expression in the liver,kidney,and lung of rats in the I/R + D group was significantly lower than the rats in the I/R group(P < 0.05).CONCLUSION:Lymph drainage could block the "gutlymph" pathway,improve intestinal barrier function,and attenuate distant organ injury incurred by intestinal I/R.
基金Supported by the National Science and Technology Major Project of China under Grant No 2013ZX02308-002the National Natural Sciences Foundation of China under Grant Nos 61574108,61334002,61474086 and 61306017
文摘Nearly lattice-matched InAIGaN/GaN heterostructure is grown on sapphire substrates by pulsed metal organic chemical vapor deposition and excellent high electron mobility transistors are fabricated on this heterostructure. The electron mobility is 1668.08cm2/V.s together with a high two-dimensional-electron-gas density of 1.43 × 10^13 cm-2 for the InAlCaN/CaN heterostructure of 2Onto InAlCaN quaternary barrier. High electron mobility transistors with gate dimensions of 1 × 50 μm2 and 4μm source-drain distance exhibit the maximum drain current of 763.91 mA/mm, the maximum extrinsic transconductance of 163.13 mS/mm, and current gain and maximum oscillation cutoff frequencies of 11 GHz and 21 GHz, respectively.
基金supported by the National Natural Science Foundation of China (32272807,U1703232)the National Key Research and Development Program of China (2017YFD0200200)。
文摘Ecology seeks to explain species coexistence,but experimental tests of mechanisms for coexistence are difficult to conduct.We synthesized an arbuscular mycorrhizal(AM)fungal community with three fungal species that differed in their capacity of foraging for orthophosphate(P)due to differences in soil exploration.We tested whether AM fungal species-specific hyphosphere bacterial assemblages recruited by hyphal exudates enabled differentiation among the fungi in the capacity of mobilizing soil organic P(P_(o)).We found that the less efficient space explorer,Gigaspora margarita,obtained less ^(13)C from the plant,whereas it had higher efficiencies in P_(o)mobilization and alkaline phosphatase(Al Pase)production per unit C than the two efficient space explorers,Rhizophagusintraradices and Funneliformis mosseae.Each AM fungus was associated with a distinct alp gene harboring bacterial assemblage,and the alp gene abundance and P_(o)preference of the microbiome associated with the less efficient space explorer were higher than those of the two other species.We conclude that the traits of AM fungal associated bacterial consortia cause niche differentiation.The trade-off between foraging ability and the ability to recruit effective P_(o)mobilizing microbiomes is a mechanism that allows co-existence of AM fungal species in a single plant root and surrounding soil habitat.
基金funded by the Clark County Department of Air Quality and Environmental Management
文摘A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United States. Twenty-four hour average ambient samples were collected for mass, ions, elements, organic carbon （OC）, elemental carbon （EC）, and trace organic markers analysis. Additional measurements were made to determine diurnal patterns in light-absorbing black carbon （BC） as a marker for combustion sources. Carbonaceous PM sources of on-road gasoline vehicles, on-road diesel vehicles, and off-road diesel engines were characterized with their chemical profiles, as well as fuel-based emission factors, using an In-Plume Sampling System. The Effective Variance Chemical Mass Balance （EV-CMB） source apportionment model was applied to the ambient samples collected, using source profiles developed in this study as well as profiles from other relevant studies. Four main sources contributed to PM2.5 carbon within the Las Vegas Valley： （1） paved road dust, （2） on-road gasoline vehicles, （3） residential wood combustion, and （4） on-road diesel vehicles. CMB estimated that on-road mixed fleet gasoline vehicles are the largest source for OC and EC at all the sites. The contribution of paved road dust to both OC and EC was 5-10% at the four sites. On-road diesel vehicles contribute 22% of the OC and 34% of the EC at a site near the city center, which is located immediately downwind of a major freeway. Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites, These results are consistent with our conceptual model, and the research methodology may be applied to studying other urban areas.
基金supported by the 973 Program (No. 2014CB643503)National Natural Science Foundation of China (Nos. 51625304, 51373150, 51461165301, 51573055)the Open Foundation Project of the State Key Lab of Silicon Materials (No. SKL2017-08)
文摘Multi-component active materials are widely used for organic electronic devices, with every component contributing complementary and synergistic optoelectronic functions. Mixing these components generally leads to lowered crystallinity and weakened charge transport. Therefore, preparing the active materials without substantially disrupting the crystalline lattice is highly desired. Here, we show that crystallization of TIPS-pentacene from solutions in the presence of fluorescent nanofibers of a perylene bisimide derivative （PBI） leads to formation of composites with nanoflber vip incorporated in the crystal host. In spite of the binary composite structure, the TIPS-pentacene maintains the single- crystalline nature. As a result, the incorporation of the PB1 vip introduces additional fluorescence function but does not significantly reduce the charge transport property of the TIPS-pentacene host, exhibiting field-effect mobility as high as 3.34 cm^2 V^-1 s^-1 even though 26.4% of the channel area is taken over by the vip. As such, this work provides a facile approach toward high-performance multifunctional organic electronic materials.
