This paper discussed the experimental results of the performance of an organic Rankine cycle(ORC)system with an ultra-low temperature heat source.The low boiling point working medium R134a was adopted in the system.Th...This paper discussed the experimental results of the performance of an organic Rankine cycle(ORC)system with an ultra-low temperature heat source.The low boiling point working medium R134a was adopted in the system.The simulated heat source temperature(SHST)in this work was set from 39.51°C to 48.60°C by the simulated heat source module.The influence of load percentage of simulated heat source(LPSHS)between 50%and 70%,the rotary valve opening(RVO)between 20%and 100%,the resistive load between 36Ωand 180Ωor the no-load of the generator,as well as the autumn and winter ambient temperature on the system performance were studied.The results showed that the stability of the system was promoted when the generator had a resistive load.The power generation(PG)and generator speed(GS)of the system in autumn were better than in winter,but the expander pressure ratio(EPR)was lower than in winter.Keep RVO unchanged,the SHST,the mass flow rate(MFR)of the working medium,GS,and the PG of the system increased with the increasing of LPSHS for different generator resistance load values.When the RVO was 60%,LPSHS was 70%,the SHST was 44.15°C and the resistive load was 72Ω,the highest PG reached 15.11 W.Finally,a simulation formula was obtained for LPSHS,resistance load,and PG,and its correlation coefficient was between 0.9818 and 0.9901.The formula can accurately predict the PG.The experimental results showed that the standard deviation between the experimental and simulated values was below 0.0792,and the relative error was within±5%.展开更多
Metal-air batteries face a great challenge in developing efficient and durable low-cost oxygen reduction reaction(ORR)electrocatalysts.Single-atom iron catalysts embedded into nitrogen doped carbon(Fe-N-C)have emerged...Metal-air batteries face a great challenge in developing efficient and durable low-cost oxygen reduction reaction(ORR)electrocatalysts.Single-atom iron catalysts embedded into nitrogen doped carbon(Fe-N-C)have emerged as attractive materials for potential replacement of Pt in ORR,but their catalytic performance was limited by the symmetrical electronic structure distribution around the single-atom Fe site.Here,we report our findings in significantly enhancing the ORR performance of Fe-N-C by moderate Fe_(2)O_(3) integration via the strong electronic interaction.Remarkably,the optimized catalyst(M-Fe_(2)O_(3)/Fe_(SA)@NC)exhibits excellent activity,durability and good tolerance to methanol,outperforming the benchmark Pt/C catalyst.When M-Fe_(2)O_(3)/Fe_(SA)@NC catalyst was used in a practical zinc-air battery assembly,peak power density of 155 mW cm^(-2)and specific capacity of 762 mA h g_(Zn)^(-1)were achieved and the battery assembly has shown superior cycling stability over a period of 200 h.More importantly,theoretical studies suggest that the introduction of Fe_(2)O_(3) can evoke the crystal field alteration and electron redistribution on single Fe atoms,which can break the symmetric charge distribution of Fe-N_(4) and thereby optimize the corresponding adsorption energy of intermediates to promote the O_(2)reduction.This study provides a new pathway to promote the catalytic performance of single-atom catalysts.展开更多
AIM: To explore the contribution of AXIN1, AXIN2 and beta-catenin, components of Wnt signaling pathway, to the carcinogenesis of gastric cancer (GC), we examined AXIN1, AXIN2 exon7 and CTNNB1 (encoding beta- catenin) ...AIM: To explore the contribution of AXIN1, AXIN2 and beta-catenin, components of Wnt signaling pathway, to the carcinogenesis of gastric cancer (GC), we examined AXIN1, AXIN2 exon7 and CTNNB1 (encoding beta- catenin) exon3 mutations in 70 GCs. METHODS: The presence of mutations was identified by polymerase chain reaction (PCR)-based denaturing high-performance liquid chromatography and direct DNA sequencing. Beta-catenin expression was detected by immunohistochemical analysis. RESULTS: Among the 70 GCs, 5 (7.1%) had mutations in one or two of these three components. A frameshift mutation (1 bp deletion) in exon7 of AXIN2 was found in one case. Four cases, including the case with a mutation in AXIN2, had frameshift mutations and missense mutations in AXIN1. Five single nucleotide polymorphisms (SNPs), 334 C>T, 874 C>T, 1396 G>A, 1690 C>T and 1942 T>G, were identified in AXIN1. A frameshift mutation (27 bp deletion) spanning exon3 of CTNNB1 was observed in one case. All four cases with mutations in AXIN1 and AXIN2 showed nuclear beta- catenin expression. CONCLUSION: These data indicate that the mutationsin AXIN1 and AXIN2 may contribute to gastric carcino- genesis.展开更多
Objective:To identify serum biomarkers that may predict the short or long term outcomes of anti-Helicobacter pylori(H.pylori)treatment,a follow-up study was performed based on an intervention trial in Linqu County,Chi...Objective:To identify serum biomarkers that may predict the short or long term outcomes of anti-Helicobacter pylori(H.pylori)treatment,a follow-up study was performed based on an intervention trial in Linqu County,China.Methods:A total of 529 subjects were selected randomly from 1,803 participants to evaluate total anti-H.pylori immunoglobulin G(Ig G)and 10 specific antibody levels before and after treatment at 1-,2-and 7.3-year.The outcomes of anti-H.pylori treatment were also parallelly assessed by 13C-urea breath test at 45-d after treatment and 7.3-year at the end of follow-up.Results:We found the medians of anti-H.pylori Ig G titers were consistently below cut-off value through 7.3years in eradicated group,however,the medians declined in recurrence group to 1.2 at 1-year after treatment and slightly increased to 2.0 at 7.3-year.While the medians were significantly higher(>3.0 at 2-and 7.3-year)among subjects who failed the eradication or received placebo.For specific antibody responses,baseline seropositivities of Fli D and Hpa A were reversely associated with eradication failure[for Fli D,odds ratio(OR)=0.44,95%confidence interval(95%CI):0.27–0.73;for Hpa A,OR=0.32,95%CI:0.17–0.60].The subjects with multiple positive specific antibodies at baseline were more likely to be successfully eradicated in a linear fashion(Ptrend=0.006).Conclusions:Our study suggested that total anti-H.pylori Ig G level may serve as a potential monitor of longterm impact on anti-H.pylori treatment,and priority for H.pylori treatment may be endowed to the subjects with multiple seropositive antibodies at baseline,especially for Fli D and Hap A.展开更多
AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled study.METHODS: From 2004 to 2006, a total ...AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled study.METHODS: From 2004 to 2006, a total of 1024 Chinese patients (aged 35 to 64 years) with severe chronic atrophic gastritis, intestinal metaplasia or dysplasia were randomly assigned to receive 200 mg of celecoxib twice daily or placebo in Linqu County (Shandong Province, China), a high-risk area of gastric cancer. All gastroduodenal ulcer and cardiovascular events occurred were recorded and the patients were followed up for 1.5 years after treatment. At the end of the trial, a systematic interview survey about other adverse events was conducted. RESULTS: Gastroduodenal ulcer was detected in 19 of 463 (3.72%) patients who received celecoxib and 17 of 473 (3.31%) patients who received placebo, respectively (odds ratio = 1.13, 95% CI = 0.58-2.19). Cardiovascular (CV) events occurred in 4 patients who received celecoxib and in 5 patients who received placebo, respectively. Compared with those who received placebo, patients who received celecoxib had no signif icant increase in occurrence of CV events (hazard ratio = 0.84, 95% CI = 0.23-3.15). Among the adverse events acquired by interview survey, only the frequency of bloating was signif icantly higher in patients treated with celecoxib than in those treated with placebo. CONCLUSION: Treatment of gastric cancer with celecoxib is not associated with increased risk of gastroduodenal ulcer and cardiovascular events.展开更多
In this paper, we propose a novel method for finger-vein recognition. We extract the features of the vein patterns for recognition. Then, the minutiae features included bifurcation points and ending points are extract...In this paper, we propose a novel method for finger-vein recognition. We extract the features of the vein patterns for recognition. Then, the minutiae features included bifurcation points and ending points are extracted from these vein patterns. These feature points are used as a geometric representation of the vein patterns shape. Finally, the modified Hausdorff distance algorithm is provided to evaluate the identifica-tion ability among all possible relative positions of the vein patterns shape. This algorithm has been widely used for comparing point sets or edge maps since it does not require point cor-respondence. Experimental results show these minutiae feature points can be used to perform personal verification tasks as a geometric rep-resentation of the vein patterns shape. Fur-thermore, in this developed method. we can achieve robust image matching under different lighting conditions.展开更多
Objective The potential of all central nervous system synapses to exhibit long term potentiation (LTP) or long term depression (LTD) is subject to modulation by prior synaptic activity, a higher-order form of plastici...Objective The potential of all central nervous system synapses to exhibit long term potentiation (LTP) or long term depression (LTD) is subject to modulation by prior synaptic activity, a higher-order form of plasticity that has been termed metaplasticity. This study is designed to examine the plasticity and metaplasticity in the lateral perforant path of rat. Methods Field potential was measured with different priming and conditioning stimulation protocols. Results Ten-hertz priming, which does not affect basal synaptic transmission, caused a dramatic reduction in subsequent LTP at lateral perforant path synapses in vitro, and the reduced LTP lasted for at least 2 h. The LTD was unaffected. The reduction of LTP in the lateral perforant path was also readily induced by applying priming antidromically at the mossy fibers. Conclu- sion Priming with 10 Hz, which is within a frequency range observed during physiological activity, can cause potent, long-lasting inhibition of LTP, but not LTD. This form of metaplasticity adds a layer of complexity to the activity-depen- dent modification of synapses within the dentate gyrus.展开更多
Objective:To study the influence of propofol or etomidate combined with remifentanil in painless gastroscopy on inflammatory stress response.Methods: 117 patients with suspected gastritis who underwent painless gastro...Objective:To study the influence of propofol or etomidate combined with remifentanil in painless gastroscopy on inflammatory stress response.Methods: 117 patients with suspected gastritis who underwent painless gastroscopy in our hospital between July 2015 and August 2016 were divided into propofol group (n=67) and etomidate group (n=50) according to the anesthesia schemes. Propofol group received propofol combined with remifentanil anesthesia, and etomidate group received etomidate combined with remifentanil anesthesia. The differences in serum levels of inflammatory factors, stress hormones and oxidative stress indicators were compared between the two groups before the examination (T0), immediately after the examination (T1) and 15 min after the examination (T2).Results: At T0, there were no significant differences in serum levels of inflammatory factors, stress hormones or oxidative stress indexes between the two groups (P>0.05). At T1 and T2, serum inflammatory factors IL-1, IL-6 and CRP levels of etomidate group were lower than those of propofol group;serum stress hormones Cor, NE and E levels were lower than those of propofol group;serum oxidation indexes AOPPs and LHP levels were lower than those of propofol group while anti-oxidation indexes CAT and SOD levels were higher than those of propofol group (P<0.05). Conclusion: Etomidate for painless gastroscopy is better than propofol in maintaining depth of anesthesia and reducing operation trauma.展开更多
Objective:To observe the effect of Icariin on diabetic myocardial hypertrophy and explore its molecular mechanism.Methods:C57BL/6 mice were randomly divided into Ctrl group(normal control group),DM group(STZ intraperi...Objective:To observe the effect of Icariin on diabetic myocardial hypertrophy and explore its molecular mechanism.Methods:C57BL/6 mice were randomly divided into Ctrl group(normal control group),DM group(STZ intraperitoneal injection model),and DM+ICA group(diabetic C57BL/6 mice by intragastric Icariin solution 80mg/kg/d,for 3 consecutive weeks).Real-time quantitative PCR was used to detect myocardial hypertrophy markers BNP andβ-MHC.Western blotting was used to detect myocardial AMPK,p-AMPK,mTOR,p-mTOR,LC3B and Beclin1 protein expression.Echocardiogram was used to detect left ventricular mass and ejection fraction.Results:Compared with the normal control group,the expression of myocardial hypertrophy markers BNP andβ-MHC mRNA in diabetic mice were significantly increased;the expression of phosphorylated AMPK protein,autophagy-related protein LC3B and Beclin1 were significantly increased,and the expression of phosphorylated mTOR protein is significantly reduced;the left ventricular mass is significantly increased.The above changes can be reversed after treatment with Icariin,but the effect of Icariin is blocked by the autophagy inhibitor rapamycin.Conclusion:Icariin may inhibit autophagy and reduce diabetic myocardial hypertrophy through AMPK-mTOR signaling pathway.展开更多
Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflo...Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research.展开更多
This paper briefly summarizes the current status of typical solar thermal power plant system,including system composition,thermal energy storage medium and performance.The thermo-physical properties of the storage med...This paper briefly summarizes the current status of typical solar thermal power plant system,including system composition,thermal energy storage medium and performance.The thermo-physical properties of the storage medium are some of the most important factors that affect overall efficiency of the system,because some renewable energy sources such as solar and wind are unpredictable.A thermal storage system is therefore necessary to store energy for continuous usage.Based on the form of storage or the mode of system connection,heat exchangers of a thermal storage system can produce different temperature ranges of heat transfer fluid to realize energy cascade utilization.Founded upon the review,a small hybrid energy system with a molten-salt energy storage system is proposed to solve the problems of heating,cooling,and electricity consumption of a 1000 m2 training hall at school.The system uses molten-salt storage tank,water tank and steam generator to change the temperature of heat transfer fluid,in order to realize thermal energy cascade utilization.Compared to the existing heating and cooling system,the proposed system needs more renewable energy and less municipal energy to achieve the same results according to simulation analysis.Furthermore,by improving the original heating and cooling system,PMV has been improved.The comprehensive efficiency of solar energy utilization has been increased to 83%.展开更多
Considered as the widespread renewable energy,solar energy is used to produce the electricity and heat for carbon peaking and carbon neutralization.However,the photo-electric conversion efficiency will decrease with t...Considered as the widespread renewable energy,solar energy is used to produce the electricity and heat for carbon peaking and carbon neutralization.However,the photo-electric conversion efficiency will decrease with the increase of cells temperature.To solve this problem,a water-type hybrid photovoltaic/thermal(PV/T)solar system has been designed and tested in Hong Kong.The outdoor experiment proceeded all days in 6 months with three different operating modes.The data of selected 33 days were used to analyze the performance of the system.The results showed that the thermal efficiencies were 33.6%,52%,and 48.3%at zero reduced temperature,corresponding to three modes.Besides,the overall efficiencies were 43.2%,60.9%,and 55.2%accordingly,which are higher than those of the conventional flat-plate solar collector.The average water temperature in the storage tank could reach 39.9°C,and the system could produce 0.07 kWh electric power after one-day operation,when the collector with 96 kg/m2 M/Ac installed vertically combining with external wall for each family.It is realizable to utilize the developed building integrated water-type photovoltaic/thermal(BIPVT)solar system for residential-intensive high-rise buildings in Hong Kong,satisfying the needs of hot water,and eventually reducing energy consumption of the buildings.展开更多
Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low wh...Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low when the gas concentration is at 10^(-9)(PPB),which cannot meet the requirements of using exhaled breath to pre-diagnose diabetes.Herein,Pd-SmFeO_(3)hollow nanotubes with an extremely high specific surface area and porosity were synthesized by electrospinning.After Pd doping,the specific surface area improved by more than two times,and the acetone response improved by more than three times.In addition,the response further improved by more than 1.5 times,and the optimum operating temperature reduced by 100℃under light irradiation.Moreover,the relative humidity adaptability,long-term stability,and selectivity of the material were significantly improved after Pd doping or light irradiation.Finally,the acetone concentration in a person’s exhaled breath was detected by a Pd-SmFeO_(3)-based gas sensor,and the error was less than 10%compared to that obtained by gas chromatography-mass spectrometry method.展开更多
Androgenic alopecia(AGA)is the most common type of clinical alopecia.Androgen receptor(AR)is the most logical candidate gene for regulating the occurrence of AGA.Dermal papilla cells(DPCs)are a special kind of mesench...Androgenic alopecia(AGA)is the most common type of clinical alopecia.Androgen receptor(AR)is the most logical candidate gene for regulating the occurrence of AGA.Dermal papilla cells(DPCs)are a special kind of mesenchymal cells,located in the hair bulb of hair follicles.DPCs play a role in maintaining and inducing the periodic cycling of hair follicles,and are considered as a key cell target of androgen in hair follicles.展开更多
基金This work was supported by Tianjin Natural Science Foundation(No.21JCZDJC00750).
文摘This paper discussed the experimental results of the performance of an organic Rankine cycle(ORC)system with an ultra-low temperature heat source.The low boiling point working medium R134a was adopted in the system.The simulated heat source temperature(SHST)in this work was set from 39.51°C to 48.60°C by the simulated heat source module.The influence of load percentage of simulated heat source(LPSHS)between 50%and 70%,the rotary valve opening(RVO)between 20%and 100%,the resistive load between 36Ωand 180Ωor the no-load of the generator,as well as the autumn and winter ambient temperature on the system performance were studied.The results showed that the stability of the system was promoted when the generator had a resistive load.The power generation(PG)and generator speed(GS)of the system in autumn were better than in winter,but the expander pressure ratio(EPR)was lower than in winter.Keep RVO unchanged,the SHST,the mass flow rate(MFR)of the working medium,GS,and the PG of the system increased with the increasing of LPSHS for different generator resistance load values.When the RVO was 60%,LPSHS was 70%,the SHST was 44.15°C and the resistive load was 72Ω,the highest PG reached 15.11 W.Finally,a simulation formula was obtained for LPSHS,resistance load,and PG,and its correlation coefficient was between 0.9818 and 0.9901.The formula can accurately predict the PG.The experimental results showed that the standard deviation between the experimental and simulated values was below 0.0792,and the relative error was within±5%.
基金supported by the Australian Research Council Australian Laureate Fellowship(No.FL200100049)the support of Natural Science Foundation for Young Scholars of Jiangsu Province(No.BK20220879)+1 种基金National Natural Science Foundation for Young Scholars of China(No.22209072)Monash University for a PhD scholarship as part of the university support for establishment of the ARC Research Hub for Energy-efficient Separation(H170100009)。
文摘Metal-air batteries face a great challenge in developing efficient and durable low-cost oxygen reduction reaction(ORR)electrocatalysts.Single-atom iron catalysts embedded into nitrogen doped carbon(Fe-N-C)have emerged as attractive materials for potential replacement of Pt in ORR,but their catalytic performance was limited by the symmetrical electronic structure distribution around the single-atom Fe site.Here,we report our findings in significantly enhancing the ORR performance of Fe-N-C by moderate Fe_(2)O_(3) integration via the strong electronic interaction.Remarkably,the optimized catalyst(M-Fe_(2)O_(3)/Fe_(SA)@NC)exhibits excellent activity,durability and good tolerance to methanol,outperforming the benchmark Pt/C catalyst.When M-Fe_(2)O_(3)/Fe_(SA)@NC catalyst was used in a practical zinc-air battery assembly,peak power density of 155 mW cm^(-2)and specific capacity of 762 mA h g_(Zn)^(-1)were achieved and the battery assembly has shown superior cycling stability over a period of 200 h.More importantly,theoretical studies suggest that the introduction of Fe_(2)O_(3) can evoke the crystal field alteration and electron redistribution on single Fe atoms,which can break the symmetric charge distribution of Fe-N_(4) and thereby optimize the corresponding adsorption energy of intermediates to promote the O_(2)reduction.This study provides a new pathway to promote the catalytic performance of single-atom catalysts.
文摘AIM: To explore the contribution of AXIN1, AXIN2 and beta-catenin, components of Wnt signaling pathway, to the carcinogenesis of gastric cancer (GC), we examined AXIN1, AXIN2 exon7 and CTNNB1 (encoding beta- catenin) exon3 mutations in 70 GCs. METHODS: The presence of mutations was identified by polymerase chain reaction (PCR)-based denaturing high-performance liquid chromatography and direct DNA sequencing. Beta-catenin expression was detected by immunohistochemical analysis. RESULTS: Among the 70 GCs, 5 (7.1%) had mutations in one or two of these three components. A frameshift mutation (1 bp deletion) in exon7 of AXIN2 was found in one case. Four cases, including the case with a mutation in AXIN2, had frameshift mutations and missense mutations in AXIN1. Five single nucleotide polymorphisms (SNPs), 334 C>T, 874 C>T, 1396 G>A, 1690 C>T and 1942 T>G, were identified in AXIN1. A frameshift mutation (27 bp deletion) spanning exon3 of CTNNB1 was observed in one case. All four cases with mutations in AXIN1 and AXIN2 showed nuclear beta- catenin expression. CONCLUSION: These data indicate that the mutationsin AXIN1 and AXIN2 may contribute to gastric carcino- genesis.
基金supported by the National Natural Science Foundation of China (No. 81171989, 30801346)National Basic Research Program of China (973 Program: 2010CB529303)the Capital Health Research and Development of Special (2014-2-1022)
文摘Objective:To identify serum biomarkers that may predict the short or long term outcomes of anti-Helicobacter pylori(H.pylori)treatment,a follow-up study was performed based on an intervention trial in Linqu County,China.Methods:A total of 529 subjects were selected randomly from 1,803 participants to evaluate total anti-H.pylori immunoglobulin G(Ig G)and 10 specific antibody levels before and after treatment at 1-,2-and 7.3-year.The outcomes of anti-H.pylori treatment were also parallelly assessed by 13C-urea breath test at 45-d after treatment and 7.3-year at the end of follow-up.Results:We found the medians of anti-H.pylori Ig G titers were consistently below cut-off value through 7.3years in eradicated group,however,the medians declined in recurrence group to 1.2 at 1-year after treatment and slightly increased to 2.0 at 7.3-year.While the medians were significantly higher(>3.0 at 2-and 7.3-year)among subjects who failed the eradication or received placebo.For specific antibody responses,baseline seropositivities of Fli D and Hpa A were reversely associated with eradication failure[for Fli D,odds ratio(OR)=0.44,95%confidence interval(95%CI):0.27–0.73;for Hpa A,OR=0.32,95%CI:0.17–0.60].The subjects with multiple positive specific antibodies at baseline were more likely to be successfully eradicated in a linear fashion(Ptrend=0.006).Conclusions:Our study suggested that total anti-H.pylori Ig G level may serve as a potential monitor of longterm impact on anti-H.pylori treatment,and priority for H.pylori treatment may be endowed to the subjects with multiple seropositive antibodies at baseline,especially for Fli D and Hap A.
基金(in part) Grants from National High Technology R&D Program (No. 2002BA711A06) National "211" Project in Peking University 529 and 533, Beijing Municipal Commission of Science and Technology (No. H209-20030130)+1 种基金 National Natural Science Foundation of China (No. 30471957)Research Grant Council Earmarked Grant (HKU 7256/01M) of the Hong Kong Special Administration Region, and Research Grant from Peking University School of Oncology, Beijing Cancer Hospital & Institute, China
文摘AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled study.METHODS: From 2004 to 2006, a total of 1024 Chinese patients (aged 35 to 64 years) with severe chronic atrophic gastritis, intestinal metaplasia or dysplasia were randomly assigned to receive 200 mg of celecoxib twice daily or placebo in Linqu County (Shandong Province, China), a high-risk area of gastric cancer. All gastroduodenal ulcer and cardiovascular events occurred were recorded and the patients were followed up for 1.5 years after treatment. At the end of the trial, a systematic interview survey about other adverse events was conducted. RESULTS: Gastroduodenal ulcer was detected in 19 of 463 (3.72%) patients who received celecoxib and 17 of 473 (3.31%) patients who received placebo, respectively (odds ratio = 1.13, 95% CI = 0.58-2.19). Cardiovascular (CV) events occurred in 4 patients who received celecoxib and in 5 patients who received placebo, respectively. Compared with those who received placebo, patients who received celecoxib had no signif icant increase in occurrence of CV events (hazard ratio = 0.84, 95% CI = 0.23-3.15). Among the adverse events acquired by interview survey, only the frequency of bloating was signif icantly higher in patients treated with celecoxib than in those treated with placebo. CONCLUSION: Treatment of gastric cancer with celecoxib is not associated with increased risk of gastroduodenal ulcer and cardiovascular events.
文摘In this paper, we propose a novel method for finger-vein recognition. We extract the features of the vein patterns for recognition. Then, the minutiae features included bifurcation points and ending points are extracted from these vein patterns. These feature points are used as a geometric representation of the vein patterns shape. Finally, the modified Hausdorff distance algorithm is provided to evaluate the identifica-tion ability among all possible relative positions of the vein patterns shape. This algorithm has been widely used for comparing point sets or edge maps since it does not require point cor-respondence. Experimental results show these minutiae feature points can be used to perform personal verification tasks as a geometric rep-resentation of the vein patterns shape. Fur-thermore, in this developed method. we can achieve robust image matching under different lighting conditions.
基金supported by a grant from the Program of National Natural Science Foundation of China(No.30772515)the National"863"High-Tech Res & Dev Program of China(No.2006A A02A402)
文摘Objective The potential of all central nervous system synapses to exhibit long term potentiation (LTP) or long term depression (LTD) is subject to modulation by prior synaptic activity, a higher-order form of plasticity that has been termed metaplasticity. This study is designed to examine the plasticity and metaplasticity in the lateral perforant path of rat. Methods Field potential was measured with different priming and conditioning stimulation protocols. Results Ten-hertz priming, which does not affect basal synaptic transmission, caused a dramatic reduction in subsequent LTP at lateral perforant path synapses in vitro, and the reduced LTP lasted for at least 2 h. The LTD was unaffected. The reduction of LTP in the lateral perforant path was also readily induced by applying priming antidromically at the mossy fibers. Conclu- sion Priming with 10 Hz, which is within a frequency range observed during physiological activity, can cause potent, long-lasting inhibition of LTP, but not LTD. This form of metaplasticity adds a layer of complexity to the activity-depen- dent modification of synapses within the dentate gyrus.
文摘Objective:To study the influence of propofol or etomidate combined with remifentanil in painless gastroscopy on inflammatory stress response.Methods: 117 patients with suspected gastritis who underwent painless gastroscopy in our hospital between July 2015 and August 2016 were divided into propofol group (n=67) and etomidate group (n=50) according to the anesthesia schemes. Propofol group received propofol combined with remifentanil anesthesia, and etomidate group received etomidate combined with remifentanil anesthesia. The differences in serum levels of inflammatory factors, stress hormones and oxidative stress indicators were compared between the two groups before the examination (T0), immediately after the examination (T1) and 15 min after the examination (T2).Results: At T0, there were no significant differences in serum levels of inflammatory factors, stress hormones or oxidative stress indexes between the two groups (P>0.05). At T1 and T2, serum inflammatory factors IL-1, IL-6 and CRP levels of etomidate group were lower than those of propofol group;serum stress hormones Cor, NE and E levels were lower than those of propofol group;serum oxidation indexes AOPPs and LHP levels were lower than those of propofol group while anti-oxidation indexes CAT and SOD levels were higher than those of propofol group (P<0.05). Conclusion: Etomidate for painless gastroscopy is better than propofol in maintaining depth of anesthesia and reducing operation trauma.
基金Project of Medical and Health Research,Gansu Province(No.GSWSKY2020-13)。
文摘Objective:To observe the effect of Icariin on diabetic myocardial hypertrophy and explore its molecular mechanism.Methods:C57BL/6 mice were randomly divided into Ctrl group(normal control group),DM group(STZ intraperitoneal injection model),and DM+ICA group(diabetic C57BL/6 mice by intragastric Icariin solution 80mg/kg/d,for 3 consecutive weeks).Real-time quantitative PCR was used to detect myocardial hypertrophy markers BNP andβ-MHC.Western blotting was used to detect myocardial AMPK,p-AMPK,mTOR,p-mTOR,LC3B and Beclin1 protein expression.Echocardiogram was used to detect left ventricular mass and ejection fraction.Results:Compared with the normal control group,the expression of myocardial hypertrophy markers BNP andβ-MHC mRNA in diabetic mice were significantly increased;the expression of phosphorylated AMPK protein,autophagy-related protein LC3B and Beclin1 were significantly increased,and the expression of phosphorylated mTOR protein is significantly reduced;the left ventricular mass is significantly increased.The above changes can be reversed after treatment with Icariin,but the effect of Icariin is blocked by the autophagy inhibitor rapamycin.Conclusion:Icariin may inhibit autophagy and reduce diabetic myocardial hypertrophy through AMPK-mTOR signaling pathway.
基金supported by the Tianjin Science and Technology Project(Project No.19JCTPJC44300)The Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Project No.2018KJ261)Science and Technology Program Project of Jin Nan District Tianjin(Project Nos.201805015&20190111).
文摘Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research.
基金funded by 2017 Research Project of Tianjin Sino-German University of Applied Sciences(Project No.zdkt2017-001)The Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Project No.2018KJ260)The Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Project No.2020ZD03).
文摘This paper briefly summarizes the current status of typical solar thermal power plant system,including system composition,thermal energy storage medium and performance.The thermo-physical properties of the storage medium are some of the most important factors that affect overall efficiency of the system,because some renewable energy sources such as solar and wind are unpredictable.A thermal storage system is therefore necessary to store energy for continuous usage.Based on the form of storage or the mode of system connection,heat exchangers of a thermal storage system can produce different temperature ranges of heat transfer fluid to realize energy cascade utilization.Founded upon the review,a small hybrid energy system with a molten-salt energy storage system is proposed to solve the problems of heating,cooling,and electricity consumption of a 1000 m2 training hall at school.The system uses molten-salt storage tank,water tank and steam generator to change the temperature of heat transfer fluid,in order to realize thermal energy cascade utilization.Compared to the existing heating and cooling system,the proposed system needs more renewable energy and less municipal energy to achieve the same results according to simulation analysis.Furthermore,by improving the original heating and cooling system,PMV has been improved.The comprehensive efficiency of solar energy utilization has been increased to 83%.
基金the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Project No.2020ZD03)Tianjin Science and Technology Plan Project Technical Innovation and Guide Special Project Science and Technology Commissioner Project(Grant No.21YDTPJC01000).
文摘Considered as the widespread renewable energy,solar energy is used to produce the electricity and heat for carbon peaking and carbon neutralization.However,the photo-electric conversion efficiency will decrease with the increase of cells temperature.To solve this problem,a water-type hybrid photovoltaic/thermal(PV/T)solar system has been designed and tested in Hong Kong.The outdoor experiment proceeded all days in 6 months with three different operating modes.The data of selected 33 days were used to analyze the performance of the system.The results showed that the thermal efficiencies were 33.6%,52%,and 48.3%at zero reduced temperature,corresponding to three modes.Besides,the overall efficiencies were 43.2%,60.9%,and 55.2%accordingly,which are higher than those of the conventional flat-plate solar collector.The average water temperature in the storage tank could reach 39.9°C,and the system could produce 0.07 kWh electric power after one-day operation,when the collector with 96 kg/m2 M/Ac installed vertically combining with external wall for each family.It is realizable to utilize the developed building integrated water-type photovoltaic/thermal(BIPVT)solar system for residential-intensive high-rise buildings in Hong Kong,satisfying the needs of hot water,and eventually reducing energy consumption of the buildings.
基金financially supported by Shandong Natural Science Foundation(No.ZR2021QE265)the Fundamental Research Funds of Taishan University(No.Y01-2020015)+1 种基金the National Natural Science Foundation of China(Nos.61574098,61204051)Shandong Province Key Research and Development Program(No.2019GGX101016)。
文摘Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low when the gas concentration is at 10^(-9)(PPB),which cannot meet the requirements of using exhaled breath to pre-diagnose diabetes.Herein,Pd-SmFeO_(3)hollow nanotubes with an extremely high specific surface area and porosity were synthesized by electrospinning.After Pd doping,the specific surface area improved by more than two times,and the acetone response improved by more than three times.In addition,the response further improved by more than 1.5 times,and the optimum operating temperature reduced by 100℃under light irradiation.Moreover,the relative humidity adaptability,long-term stability,and selectivity of the material were significantly improved after Pd doping or light irradiation.Finally,the acetone concentration in a person’s exhaled breath was detected by a Pd-SmFeO_(3)-based gas sensor,and the error was less than 10%compared to that obtained by gas chromatography-mass spectrometry method.
基金This work was supported by The National Natural Science Foundation of China(No.82073460,82173446,82103761).
文摘Androgenic alopecia(AGA)is the most common type of clinical alopecia.Androgen receptor(AR)is the most logical candidate gene for regulating the occurrence of AGA.Dermal papilla cells(DPCs)are a special kind of mesenchymal cells,located in the hair bulb of hair follicles.DPCs play a role in maintaining and inducing the periodic cycling of hair follicles,and are considered as a key cell target of androgen in hair follicles.
