Objective Hyperbaric oxygen treatment(HBOT)has demonstrated efficacy in improving hearing levels of patients with idiopathic sudden sensorineural hearing loss(ISSHL);however,the underlying mechanisms are not well unde...Objective Hyperbaric oxygen treatment(HBOT)has demonstrated efficacy in improving hearing levels of patients with idiopathic sudden sensorineural hearing loss(ISSHL);however,the underlying mechanisms are not well understood.HBOT alleviates the inflammatory response,which is mediated by Toll-like receptor(TLR)4 and nuclear factor(NF)-κB.In this study we investigated whether HBOT attenuates inflammation in ISHHL patients via alteration of TLR4 and NF-κB expression.Methods ISHHL patients(n=120)and healthy control subjects(n=20)were enrolled in this study.Patients were randomly divided into medicine group treated with medicine only(n=60)and HBO group receiving both HBOT and medicine(n=60).Audiometric testing was performed pre-and posttreatment.TLR4,NF-кB,and TNF-αexpression in peripheral blood of ISSHL patients and healthy control subjects was assessed by ELISA before and after treatment.Results TLR4,NF-κB,and TNF-αlevels were upregulated in ISSHL patients relative to healthy control subjects;the levels were decreased following treatment and were lower in the HBO group than that in the medicine group post-treatment(P<0.05 and P<0.01).Conclusion HBOT alleviates hearing loss in ISSHL patients by suppressing the inflammatory response induced by TLR4 and NF-κB signaling.展开更多
As the global burden of diabetes is rapidly increasing,the incidence of diabetic foot ulcers is continuously increasing as the mean age of the world population increases and the obesity epidemic advances.A significant...As the global burden of diabetes is rapidly increasing,the incidence of diabetic foot ulcers is continuously increasing as the mean age of the world population increases and the obesity epidemic advances.A significant percentage of diabetic foot ulcers are caused by mixed micro and macro-vascular dysfunction leading to impaired perfusion of foot tissue.Left untreated,chronic limb-threatening ischemia has a poor prognosis and is correlated with limb loss and increased mortality;prompt treatment is required.In this review,the diagnostic challenges in diabetic foot disease are discussed and available data on minimally invasive treatment options such as endovascular revascularization,stem cells,and gene therapy are examined.展开更多
Hyperbaric oxygen therapy as a new treatment approach for Alzheimer’s disease(AD):Alongside the increase in life expectancy,the prevalence of age-related disorders,such as neurodegenerative diseases,is on the rise...Hyperbaric oxygen therapy as a new treatment approach for Alzheimer’s disease(AD):Alongside the increase in life expectancy,the prevalence of age-related disorders,such as neurodegenerative diseases,is on the rise.For example,AD,the most common form of dementia in the elderly,accounts for 60–80%of all dementia cases.展开更多
The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and diso...The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and disordered carbon on the surface of the particles are etched away,so that diamond with regular crystal plane,smaller lattice stress,and better crystal quality is exposed,producing a Ge-V photoluminescence(PL)intensity 4 times stronger and PL peak FWHM(full width at half maximum)value of 6.6 nm smaller than the as-deposited sample.It is observed that the cycles of‘diamond is converted into graphite and disordered carbon,then the graphite and disordered carbon are etched’can occur with the treatment time further increasing.During these cycles,the particle surface alternately appears smooth and rough,corresponding to the strengthening and weakening of Ge-V PL intensity,respectively,while the PL intensity is always stronger than that of the as-deposited sample.The results suggest that not only graphite but also disordered carbon weakens the Ge-V PL intensity.Our study provides a feasible way of enhancing the Ge-V PL properties and effectively controlling the surface morphology of diamond particle.展开更多
Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain inju...Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain injury were treated by routine therapy combined with HBOT and 29 patients by routine therapy.展开更多
Objective:To determine the effect of hyperbaric oxygenation(HBO) on treating acute cerebral infarction(ACI). Methods: We randomly divided 60 patients with acute cerebral infarction into the treatment group and the con...Objective:To determine the effect of hyperbaric oxygenation(HBO) on treating acute cerebral infarction(ACI). Methods: We randomly divided 60 patients with acute cerebral infarction into the treatment group and the control group. Hyperbaric oxygenation treatment was applied in the treatment group as routine drug therapy was used. The neurological function, living ability, clinical therapeutic effectiveness and hemorrheology changes of pa tients in the two groups before and after treatment were observed and evaluated. Results: The indexes of treatment were obviously improved one month after treatment (P < 0.05 ). Clinical effective rate was 93.3 % in this group,which was obviously higher than that of the control group(P < 0.05). Conclusion: Hyperbaric oxygenation can accelerate the recovery of neurological function of patients with acute cerebral infarction.展开更多
The time evolution of oxygen plasma treated polystyrene(PS)surfaces was investigated upon storing them in theair under controlled humidity conditions.The methods of water contact angle,X-ray photoelectron spectroscopy...The time evolution of oxygen plasma treated polystyrene(PS)surfaces was investigated upon storing them in theair under controlled humidity conditions.The methods of water contact angle,X-ray photoelectron spectroscopy(XPS),sumfrequency generation(SFG)vibrational spectroscopy,and atomic force microscopy(AFM)were used to infer the surfaceproperties and structure.Chemical groups containing oxygen were formed on the PS surface with the plasma treatment,demonstrated by water contact angle and XPS.The surface polarity decayed markedly on time,as assessed by steady increasein the water contact angle as a function of storage time,from zero to around 60°.The observed decay is interpreted as arisingfrom surface rearrangement processes to burying polar groups away from the uppermost layer of the surfaces,which is incontact with air.On the other hand,XPS results show that the chemical composition in the first 3 nm surface layer isunaffected by the surface aging,and the depth profile of oxygen is essentially the same with time.A possible change of PSsurface roughness was examined by AFM,and it showed that the increase of water contact angle during surface aging couldnot be attributed to surface roughness.Thus,it is concluded that surface aging is attributable to surface reorganization andthe motion of oxygen containing groups is confined within the XPS probing depth.SFG spectroscopy,which is intrinsicallyinterface-specific,was used to detect the chemical structure of PS surface at the molecular level after various aging times.The results are interpreted as follows.During the aging of the plasma treated PS surfaces,the oxygen containing groupsundergo reorientation processes toward the polymer bulk and/or parallel to the surface,while the CH_2 moiety stands up onthe PS surface.Our results indicate that the surface configuration changes do not require large length scale segmentalmotions or migration of macromolecules.Motions that are responsible for surface configuration changes could be relativelysmall rotational motions.The aging behaviors under different relative humidity conditions were shown to be similar from18% to 91%,whereas the kinetics of surface polarity decays were faster in higher relative humidity.Here,the surfacerearrangement of polystyrene films that were previously treated by oxygen plasma and aged,and was investigated in terms ofcontact angle after the water immersion.The contact angles of the water-immersed samples were found to change andapproach the initial values before the immersion asymptotically.展开更多
Background:Hyperbaric oxygen treatment(HBOT)has been demonstrated to influence the keloid recurrence rate after surgery and to relieve keloid symptoms and other pathological processes in keloids.To explore the mechani...Background:Hyperbaric oxygen treatment(HBOT)has been demonstrated to influence the keloid recurrence rate after surgery and to relieve keloid symptoms and other pathological processes in keloids.To explore the mechanism of the effect of HBOT on keloids,tumor immune gene expression and immune cell infiltration were studied in this work.Methods:From February 2021 to April 2021,HBOT was carried out on keloid patients four times before surgery.Keloid tissue samples were collected and divided into an HBOT group(keloid with HBOT before surgery[HK]group,n=6)and a non-HBOT group(K group,n=6).Tumor gene expression was analyzed with an Oncomine Immune Response Research Assay kit.Data were mined with R package.The differentially expressed genes between the groups were compared.Hub genes between the groups were determined and verified with Quantitative Real-time PCR.Immune cell infiltration was analyzed based on CIBERSORT deconvolution algorithm analysis of gene expression and verified with immunohistochemistry(IHC).Results:Inflammatory cell infiltration was reduced in the HK group.There were 178 upregulated genes and 217 downregulated genes.Ten hub genes were identified,including Integrin Subunit Alpha M(ITGAM),interleukin(IL)-4,IL-6,IL-2,Protein Tyrosine Phosphatase Receptor Type C(PTPRC),CD86,transforming growth factor(TGF),CD80,CTLA4,and IL-10.CD80,ITGAM,IL-4,and PTPRC with significantly downregulated expression were identified.IL-10 and IL-2 were upregulated in the HK group but without a significant difference.Infiltration differences of CD8 lymphocyte T cells,CD4 lymphocyte T-activated memory cells,and dendritic resting cells were identified with gene CIBERSORT deconvolution algorithm analysis.Infiltration levels of CD4 lymphocyte T cell in the HK group were significantly higher than those of the K group in IHC verification.Conclusion:HBOT affected tumor gene expression and immune cell infiltration in keloids.CD4 lymphocyte T cell,especially activated memory CD4+T,might be the key regulatory immune cell,and its related gene expression needs further study.展开更多
Graphene based nanosheets have been widely used as building blocks for fabrication of superior separation membrane for water processing.In particular,membranes made of reduced graphene oxide(rGO)show better stability ...Graphene based nanosheets have been widely used as building blocks for fabrication of superior separation membrane for water processing.In particular,membranes made of reduced graphene oxide(rGO)show better stability compared with graphene oxide(GO).However,densely stacked of rGO often results in low water flux.In this study,cellulose nanofibers(CNFs)were incorporated into the rGO laminates by vacuum filtration of dilute GO/CNF solution and thermal reduction at 150C for 1.5 h.The resulting rGO/CNF membrane was treated with oxygen plasma for 1–4 min to create nanopores on the membrane surface for the purpose of enhancing nano-filtration performance.The results showed that the optimum membrane performance was obtained by using the equal amount of GO(31.83 mg m^(-2))and CNFs accompanied by 3 min of plasma treatment,exhibiting a pure water permeance of 37.23.9 L m^(-2)h^(-1)bar^(-1)maintaining a rejection above 90%for Acid Fuchsin(1.2×1.1 nm),Rose Bengal(1.5×1.2 nm)and Brilliant Blue(2.2×1.7 nm).展开更多
Developing an electrically conductive and corrosion-resistant coating is essential for metal bipolar plates of polymer electrolyte membrane fuel cells(PEMFCs). Although enhanced corrosion resistance was seen for Cr co...Developing an electrically conductive and corrosion-resistant coating is essential for metal bipolar plates of polymer electrolyte membrane fuel cells(PEMFCs). Although enhanced corrosion resistance was seen for Cr coated stainless steel(Cr/SS) bipolar plates, they experience a quick decrease of through-plane electrical conductivity due to the formation of a porous and low-conductive corrosion product layer at the plate surface, thus leading to an increase in interfacial contact resistance(ICR). To tackle this issue, the multilayer Cr coatings were deposited using the magnetron sputtering with a remote inductively coupled oxygen plasma(O-ICP) in the present study. After the O-ICP treatment, a Cr oxide layer(Cr O*) is formed on the specimen surface. The Cr O*/Cr/SS has a remarkably lower stable corrosion rate(iss) than that of the native Cr oxides(Cr On/Cr/SS). Compared with Cr On/Cr/SS, the excellent performance of Cr O*/Cr/SS is attributed to a denser and thicker surface layer of Cr O* with Cr being oxidized to its highest valence state,Cr(VI). More importantly, the through-plane electrical conductivity of the specimens treated by the optimized O-ICP decreases much slowly than Cr On/Cr/SS and thus, the increament of ICR of Cr O*/Cr/SS after the potentiostatic polarization test is considerably smaller than that of Cr On/Cr/SS, which is benefited from the reduced issthat mitigates the deposition of corrosion products and hinders further oxidation of Cr coating. Therefore, Cr O*/Cr/SS proves to be a well balanced trade-off between corrosion resistance and through-plane electrical conductivity. The results of this study demonstrate that O-ICP treatment on a conductive metal coating is an effective strategy to improve the corrosion resistance and suppress the increase of ICR over the long-term polarization. The technique reported herein exhibits its promising potential application in preparing corrosion resistant and electrically conductive coatings on metal bipolar plates to be used in PEMFCs.展开更多
Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the applicatio...Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the application of conventional CC-based electrodes for zinc(Zn)storage severely hinders Zn ion transport and induces deleterious Zn dendrite growth,resulting in poor electrochemical reliability.Herein,a novel oxygen plasma-treated carbon cloth(OPCC)is rationally designed as a current collector for flexible hybrid Zn ion supercapacitors(ZISs).The modified interface of OPCC with abundant oxygenated groups enables enhanced electrolyte wettability and uniform superficial electric field distribution.A prolonged working lifespan for Zn electrodeposition is achieved by the OPCC due to the improved interfacial kinetics and homogenized ion gradient.The as-prepared hybrid ZIS also delivers excellent cycling endurance(98.5%capacity retention for 1500 cycles)with outstanding operation stability under various extreme conditions.This facile surface modification strategy provides a new way for developing future flexible electrodes for wearable electronic products.展开更多
Nitrogen-doped graphene is a promising candidate for the replacement of noble metal-based electrocatalysts for oxygen reduction reactions (ORRs). The addition of pores and holes into nitrogen-doped graphene enhances...Nitrogen-doped graphene is a promising candidate for the replacement of noble metal-based electrocatalysts for oxygen reduction reactions (ORRs). The addition of pores and holes into nitrogen-doped graphene enhances the ORR activity by introducing abundant exposed edges, accelerating mass transfer, and impeding aggregation of the graphene sheets. Herein, we present a straightforward but effective strategy for generating porous holey nitrogen-doped graphene (PHNG) via the pyrolysis of urea and magnesium acetate tetrahydrate. Due to the combined effects of the in situ generated gases and MgO nanoparticles, the synthesized PHNGs featured not only numerous out-of-plane pores among the crumpled graphene sheets, but also interpenetrated nanoscale (5-15 nm) holes in the assembled graphene. Moreover, the nitrogen doping configurations of PHNG were optimized by post-thermal treatments at different temperatures. It was found that the overall content of pyridinic and quaternary nitrogen positively correlates with the ORR activity; in particular, pyridinic nitrogen generates the most desirable characteristics for the ORR. This work reveals new routes for the synthesis of PHNG-based materials and elucidates the contributions of various nitrogen species to ORRs.展开更多
InA1N/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF...InA1N/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGs = 2 V, a low on-resistance (Ron) of 1.49 x2.mm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency (fT) is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.展开更多
基金supported by Beijing Science and Technology Special Fund[grants number 2161100000116067]。
文摘Objective Hyperbaric oxygen treatment(HBOT)has demonstrated efficacy in improving hearing levels of patients with idiopathic sudden sensorineural hearing loss(ISSHL);however,the underlying mechanisms are not well understood.HBOT alleviates the inflammatory response,which is mediated by Toll-like receptor(TLR)4 and nuclear factor(NF)-κB.In this study we investigated whether HBOT attenuates inflammation in ISHHL patients via alteration of TLR4 and NF-κB expression.Methods ISHHL patients(n=120)and healthy control subjects(n=20)were enrolled in this study.Patients were randomly divided into medicine group treated with medicine only(n=60)and HBO group receiving both HBOT and medicine(n=60).Audiometric testing was performed pre-and posttreatment.TLR4,NF-кB,and TNF-αexpression in peripheral blood of ISSHL patients and healthy control subjects was assessed by ELISA before and after treatment.Results TLR4,NF-κB,and TNF-αlevels were upregulated in ISSHL patients relative to healthy control subjects;the levels were decreased following treatment and were lower in the HBO group than that in the medicine group post-treatment(P<0.05 and P<0.01).Conclusion HBOT alleviates hearing loss in ISSHL patients by suppressing the inflammatory response induced by TLR4 and NF-κB signaling.
文摘As the global burden of diabetes is rapidly increasing,the incidence of diabetic foot ulcers is continuously increasing as the mean age of the world population increases and the obesity epidemic advances.A significant percentage of diabetic foot ulcers are caused by mixed micro and macro-vascular dysfunction leading to impaired perfusion of foot tissue.Left untreated,chronic limb-threatening ischemia has a poor prognosis and is correlated with limb loss and increased mortality;prompt treatment is required.In this review,the diagnostic challenges in diabetic foot disease are discussed and available data on minimally invasive treatment options such as endovascular revascularization,stem cells,and gene therapy are examined.
基金supported in part by the Israeli Ministry of Science,Technology and Space to UA(Grant number 3-12069)
文摘Hyperbaric oxygen therapy as a new treatment approach for Alzheimer’s disease(AD):Alongside the increase in life expectancy,the prevalence of age-related disorders,such as neurodegenerative diseases,is on the rise.For example,AD,the most common form of dementia in the elderly,accounts for 60–80%of all dementia cases.
基金the Key Project of the National Natural Science Foundation of China(Grant No.U1809210)the National Key Research and Development Program of China(Grant No.2016YFE0133200)+3 种基金the Belt and Road Initiative International Cooperation Project from Key Research and Development Program of Zhejiang Province,China(Grant No.2018C04021)the European Union’s Horizon 2020 Research and Innovation Staff Exchange Scheme(Grant No.734578)the Natural Science Foundation of Zhejiang Province,China(Grant No.LY18E020013)the International Science Technology Cooperation Program,China(Grant No.2014DFR51160).
文摘The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and disordered carbon on the surface of the particles are etched away,so that diamond with regular crystal plane,smaller lattice stress,and better crystal quality is exposed,producing a Ge-V photoluminescence(PL)intensity 4 times stronger and PL peak FWHM(full width at half maximum)value of 6.6 nm smaller than the as-deposited sample.It is observed that the cycles of‘diamond is converted into graphite and disordered carbon,then the graphite and disordered carbon are etched’can occur with the treatment time further increasing.During these cycles,the particle surface alternately appears smooth and rough,corresponding to the strengthening and weakening of Ge-V PL intensity,respectively,while the PL intensity is always stronger than that of the as-deposited sample.The results suggest that not only graphite but also disordered carbon weakens the Ge-V PL intensity.Our study provides a feasible way of enhancing the Ge-V PL properties and effectively controlling the surface morphology of diamond particle.
文摘Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain injury were treated by routine therapy combined with HBOT and 29 patients by routine therapy.
文摘Objective:To determine the effect of hyperbaric oxygenation(HBO) on treating acute cerebral infarction(ACI). Methods: We randomly divided 60 patients with acute cerebral infarction into the treatment group and the control group. Hyperbaric oxygenation treatment was applied in the treatment group as routine drug therapy was used. The neurological function, living ability, clinical therapeutic effectiveness and hemorrheology changes of pa tients in the two groups before and after treatment were observed and evaluated. Results: The indexes of treatment were obviously improved one month after treatment (P < 0.05 ). Clinical effective rate was 93.3 % in this group,which was obviously higher than that of the control group(P < 0.05). Conclusion: Hyperbaric oxygenation can accelerate the recovery of neurological function of patients with acute cerebral infarction.
基金This work was funded in part by NSF(DMR-0084301)Eastman Kodak Company.
文摘The time evolution of oxygen plasma treated polystyrene(PS)surfaces was investigated upon storing them in theair under controlled humidity conditions.The methods of water contact angle,X-ray photoelectron spectroscopy(XPS),sumfrequency generation(SFG)vibrational spectroscopy,and atomic force microscopy(AFM)were used to infer the surfaceproperties and structure.Chemical groups containing oxygen were formed on the PS surface with the plasma treatment,demonstrated by water contact angle and XPS.The surface polarity decayed markedly on time,as assessed by steady increasein the water contact angle as a function of storage time,from zero to around 60°.The observed decay is interpreted as arisingfrom surface rearrangement processes to burying polar groups away from the uppermost layer of the surfaces,which is incontact with air.On the other hand,XPS results show that the chemical composition in the first 3 nm surface layer isunaffected by the surface aging,and the depth profile of oxygen is essentially the same with time.A possible change of PSsurface roughness was examined by AFM,and it showed that the increase of water contact angle during surface aging couldnot be attributed to surface roughness.Thus,it is concluded that surface aging is attributable to surface reorganization andthe motion of oxygen containing groups is confined within the XPS probing depth.SFG spectroscopy,which is intrinsicallyinterface-specific,was used to detect the chemical structure of PS surface at the molecular level after various aging times.The results are interpreted as follows.During the aging of the plasma treated PS surfaces,the oxygen containing groupsundergo reorientation processes toward the polymer bulk and/or parallel to the surface,while the CH_2 moiety stands up onthe PS surface.Our results indicate that the surface configuration changes do not require large length scale segmentalmotions or migration of macromolecules.Motions that are responsible for surface configuration changes could be relativelysmall rotational motions.The aging behaviors under different relative humidity conditions were shown to be similar from18% to 91%,whereas the kinetics of surface polarity decays were faster in higher relative humidity.Here,the surfacerearrangement of polystyrene films that were previously treated by oxygen plasma and aged,and was investigated in terms ofcontact angle after the water immersion.The contact angles of the water-immersed samples were found to change andapproach the initial values before the immersion asymptotically.
基金supported by a grant from the National Natural Science Foundation of China(No.81871538).
文摘Background:Hyperbaric oxygen treatment(HBOT)has been demonstrated to influence the keloid recurrence rate after surgery and to relieve keloid symptoms and other pathological processes in keloids.To explore the mechanism of the effect of HBOT on keloids,tumor immune gene expression and immune cell infiltration were studied in this work.Methods:From February 2021 to April 2021,HBOT was carried out on keloid patients four times before surgery.Keloid tissue samples were collected and divided into an HBOT group(keloid with HBOT before surgery[HK]group,n=6)and a non-HBOT group(K group,n=6).Tumor gene expression was analyzed with an Oncomine Immune Response Research Assay kit.Data were mined with R package.The differentially expressed genes between the groups were compared.Hub genes between the groups were determined and verified with Quantitative Real-time PCR.Immune cell infiltration was analyzed based on CIBERSORT deconvolution algorithm analysis of gene expression and verified with immunohistochemistry(IHC).Results:Inflammatory cell infiltration was reduced in the HK group.There were 178 upregulated genes and 217 downregulated genes.Ten hub genes were identified,including Integrin Subunit Alpha M(ITGAM),interleukin(IL)-4,IL-6,IL-2,Protein Tyrosine Phosphatase Receptor Type C(PTPRC),CD86,transforming growth factor(TGF),CD80,CTLA4,and IL-10.CD80,ITGAM,IL-4,and PTPRC with significantly downregulated expression were identified.IL-10 and IL-2 were upregulated in the HK group but without a significant difference.Infiltration differences of CD8 lymphocyte T cells,CD4 lymphocyte T-activated memory cells,and dendritic resting cells were identified with gene CIBERSORT deconvolution algorithm analysis.Infiltration levels of CD4 lymphocyte T cell in the HK group were significantly higher than those of the K group in IHC verification.Conclusion:HBOT affected tumor gene expression and immune cell infiltration in keloids.CD4 lymphocyte T cell,especially activated memory CD4+T,might be the key regulatory immune cell,and its related gene expression needs further study.
基金the Australian Research Council(Project No.IH170100009)。
文摘Graphene based nanosheets have been widely used as building blocks for fabrication of superior separation membrane for water processing.In particular,membranes made of reduced graphene oxide(rGO)show better stability compared with graphene oxide(GO).However,densely stacked of rGO often results in low water flux.In this study,cellulose nanofibers(CNFs)were incorporated into the rGO laminates by vacuum filtration of dilute GO/CNF solution and thermal reduction at 150C for 1.5 h.The resulting rGO/CNF membrane was treated with oxygen plasma for 1–4 min to create nanopores on the membrane surface for the purpose of enhancing nano-filtration performance.The results showed that the optimum membrane performance was obtained by using the equal amount of GO(31.83 mg m^(-2))and CNFs accompanied by 3 min of plasma treatment,exhibiting a pure water permeance of 37.23.9 L m^(-2)h^(-1)bar^(-1)maintaining a rejection above 90%for Acid Fuchsin(1.2×1.1 nm),Rose Bengal(1.5×1.2 nm)and Brilliant Blue(2.2×1.7 nm).
基金financially supported by the National Natural Science Foundation of China(No.51901188,51701113)the Natural Science Basic Research Program from Shaanxi province(No.2020JQ-171)+2 种基金the Fundamental Research Funds for the Central Universitiesthe Canada First Research Excellence Fundthe Natural Sciences and Engineering Research Council of Canada(No.RGPIN-2016-05494)。
文摘Developing an electrically conductive and corrosion-resistant coating is essential for metal bipolar plates of polymer electrolyte membrane fuel cells(PEMFCs). Although enhanced corrosion resistance was seen for Cr coated stainless steel(Cr/SS) bipolar plates, they experience a quick decrease of through-plane electrical conductivity due to the formation of a porous and low-conductive corrosion product layer at the plate surface, thus leading to an increase in interfacial contact resistance(ICR). To tackle this issue, the multilayer Cr coatings were deposited using the magnetron sputtering with a remote inductively coupled oxygen plasma(O-ICP) in the present study. After the O-ICP treatment, a Cr oxide layer(Cr O*) is formed on the specimen surface. The Cr O*/Cr/SS has a remarkably lower stable corrosion rate(iss) than that of the native Cr oxides(Cr On/Cr/SS). Compared with Cr On/Cr/SS, the excellent performance of Cr O*/Cr/SS is attributed to a denser and thicker surface layer of Cr O* with Cr being oxidized to its highest valence state,Cr(VI). More importantly, the through-plane electrical conductivity of the specimens treated by the optimized O-ICP decreases much slowly than Cr On/Cr/SS and thus, the increament of ICR of Cr O*/Cr/SS after the potentiostatic polarization test is considerably smaller than that of Cr On/Cr/SS, which is benefited from the reduced issthat mitigates the deposition of corrosion products and hinders further oxidation of Cr coating. Therefore, Cr O*/Cr/SS proves to be a well balanced trade-off between corrosion resistance and through-plane electrical conductivity. The results of this study demonstrate that O-ICP treatment on a conductive metal coating is an effective strategy to improve the corrosion resistance and suppress the increase of ICR over the long-term polarization. The technique reported herein exhibits its promising potential application in preparing corrosion resistant and electrically conductive coatings on metal bipolar plates to be used in PEMFCs.
基金This work was financially supported by Natural Science Foundation of Jiangsu Province(BK20210480)Hong Kong Scholars Program(P0035017).
文摘Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the application of conventional CC-based electrodes for zinc(Zn)storage severely hinders Zn ion transport and induces deleterious Zn dendrite growth,resulting in poor electrochemical reliability.Herein,a novel oxygen plasma-treated carbon cloth(OPCC)is rationally designed as a current collector for flexible hybrid Zn ion supercapacitors(ZISs).The modified interface of OPCC with abundant oxygenated groups enables enhanced electrolyte wettability and uniform superficial electric field distribution.A prolonged working lifespan for Zn electrodeposition is achieved by the OPCC due to the improved interfacial kinetics and homogenized ion gradient.The as-prepared hybrid ZIS also delivers excellent cycling endurance(98.5%capacity retention for 1500 cycles)with outstanding operation stability under various extreme conditions.This facile surface modification strategy provides a new way for developing future flexible electrodes for wearable electronic products.
基金Acknowledgements We gratefully acknowledge the financial support from the National Natural Science Foundation of China (Nos. 21503253, 21403276 and 91545109), Natural Science Foundation of Shan-Xi province of China (No. 2015011010), and Youth Innovation Promotion Association CAS (No. 2015141).
文摘Nitrogen-doped graphene is a promising candidate for the replacement of noble metal-based electrocatalysts for oxygen reduction reactions (ORRs). The addition of pores and holes into nitrogen-doped graphene enhances the ORR activity by introducing abundant exposed edges, accelerating mass transfer, and impeding aggregation of the graphene sheets. Herein, we present a straightforward but effective strategy for generating porous holey nitrogen-doped graphene (PHNG) via the pyrolysis of urea and magnesium acetate tetrahydrate. Due to the combined effects of the in situ generated gases and MgO nanoparticles, the synthesized PHNGs featured not only numerous out-of-plane pores among the crumpled graphene sheets, but also interpenetrated nanoscale (5-15 nm) holes in the assembled graphene. Moreover, the nitrogen doping configurations of PHNG were optimized by post-thermal treatments at different temperatures. It was found that the overall content of pyridinic and quaternary nitrogen positively correlates with the ORR activity; in particular, pyridinic nitrogen generates the most desirable characteristics for the ORR. This work reveals new routes for the synthesis of PHNG-based materials and elucidates the contributions of various nitrogen species to ORRs.
基金supported by the National Natural Science Foundation of China(No.61306113)
文摘InA1N/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGs = 2 V, a low on-resistance (Ron) of 1.49 x2.mm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency (fT) is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.