Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma...Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma generators can match the system best.A higher power input can always bring a higher conversion,but the selectivity to C2H6 decreased from 52.48% to 39.43% as the power increased from 20W to 49W.When discharge distance was 4mm,selectivities to almost all main products reached the max.The inner electrode made of stainless steel and the outer electrode with aluminum foil were one of the best options which can obviously enhance the conversion of methane.A larger flow rate always resulted in a lower conversion of methane.In the most time,19.93% steam promoted conversion of methane.展开更多
Laboratory-reared Schizothorax davidi larvae and juveniles were examined to assess the formation and characteristics of David’s schizothoracin otoliths.Otolith development was observed and their formation period was ...Laboratory-reared Schizothorax davidi larvae and juveniles were examined to assess the formation and characteristics of David’s schizothoracin otoliths.Otolith development was observed and their formation period was verifi ed by monitoring larvae and juveniles of knownage.The results revealed that lapilli and sagittae developed before hatching,and the first otolith increment was identified at 2 days post hatching in both.The shape of lapilli was relatively stable during development compared with that of sagittae;however,growth of four sagittae and lapilli areas was consistent,but the posterior area grew faster than the anterior area and the ventral surface grew faster than the dorsal surface.Similarly,the sum length of the radius of the anterior and posterior areas on sagittae and lapilli were linearly and binomially related to total fish length,respectively.Moreover,daily deposition rates were validated by monitoring knownage larvae and juveniles.The increase in lapilli width was 1.88±0.080 0μm at the ninth increment,which reached a maximum and the decreased gradually toward the otolith edge,whereas that of sagittae increased more slowly.These results illustrate the developmental biology of S.davidi,which will aid in population conservation and fish stock management.展开更多
Objective: To study the perfusion CT features of rabbit VX2 brain tumor with correlation to MVD and VEGF, and to validate perfusion CT for reflection of tumor angiogenesis. Methods: Rabbit VX2 brain tumor model was ...Objective: To study the perfusion CT features of rabbit VX2 brain tumor with correlation to MVD and VEGF, and to validate perfusion CT for reflection of tumor angiogenesis. Methods: Rabbit VX2 brain tumor model was established by injection of 100 μL viable tumor cells (10qmL) through a 2 mm-hole 5 mm to the right of the sagittal suture and 5 mm posterior to the coronal suture bored by dental drill. MRI was performed every 2 days after seven days of implantation to evaluate the growth of the tumor. Twenty New Zealand White rabbits with tumor size over 3 mm in diameter were randomly divided into 2 groups according to the tumor growth time with those less than 3 weeks as group 1 and those more than 3 weeks as group 2, and perfusion CT were performed accordingly. CT measurements of BV, BF and PS from tumor, peritumor and contralateral normal tissue regions were obtained. After that the animals were sacrificed and 2% Evans blue (2 mL/kg) was given intravenously in 16 of these animals 1 h prior to sacrifice to detect breakdown of the blood brain barrier. VEGF and MVD were evaluated in immunohistochemical examination of the specimens. Results: Tumor had significantly higher BV, BF and PS (P=0.000) than peritumor and normal tissue region. Tumor BV, BF and MVD in group 2 were significantly higher than that in group 1 (P〈0.01). Significant linear correlation was found between MVD and BV (t=-0.915, P=-0.000), MVD and BF (t=0.901, P=-0.000), and MVD and PS (t=-0.459, P=0.042). We also found a rank correlation between PS and blue stain of tumor (rs=0.861, P=0.000). Conclusion: Perfusion CT can distinguish tumor from peritumor and normal tissue clearly, reflect tumor angiogenesis accurately, and provide useful information for the evaluation of brain tumor.展开更多
Objective: To explore the possibility of the transfection of MyoD gene induced bone marrow mesenchymal stem cells ( MSCs) to differentiate into myoblasts in vitro. Methods: The eukaryotic expression plasmid vector pIR...Objective: To explore the possibility of the transfection of MyoD gene induced bone marrow mesenchymal stem cells ( MSCs) to differentiate into myoblasts in vitro. Methods: The eukaryotic expression plasmid vector pIRES2-EGFP-MyoD was transfected into MSCs with lipotransfection method, and the positive cells were selected by G418; The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified, purified product was identified by sequencing; The reporter gene enhanced green fluorescence protein ( EFGP) was observed in the transfected cells under a fluorescent and a laser confocal microscopes; Immunohistochemical methods was used to examine the expressions of MyoD, myogenin, myosin, myoglobin and desmin in the differentiated cells. The ultrastructure changes of the cells before and after transfection were observed with electron microscopy. Results: The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified, purified product was as same in sequence as that from Genbank; Green fluorescence was observed in the transfected cells under a fluorescent and a laser confocal microscopes; Immunohistochemical methods indicated that MyoD, myogenin, myosin, myoglobin and desmin were expressed in the transfected cells; The transfected cells showed the morphological characteristics of mature cells with filaments in their cytoplasm. Conclusion: MyoD gene can induce cultured MSCs to successfully differentiate into myoblasts , probably providing an experimental foundation for trauma repair.展开更多
Objective: To evaluate the inhibitory effect of heparanase antisense oligodeoxynucleotide (AS-ODN) on the angiogenesis and metastasis of human mammary carcinoma cell xenografts in nude mice. Methods: The AS-ODN co...Objective: To evaluate the inhibitory effect of heparanase antisense oligodeoxynucleotide (AS-ODN) on the angiogenesis and metastasis of human mammary carcinoma cell xenografts in nude mice. Methods: The AS-ODN complementary to the start codon region of heparanase mRNA and its control, scrambled nonsense oligodeoxynucleotide (NS-ODN) were designed and synthesized. A subcutaneous growth model and an acute hematogenous metastasis model of human mammary carcinoma were established in nude mice and were treated with ODNs. The heparanase expression in tumor was evaluated by RT-PCR and Western blot. The microvessel density (MVD) was measured by immunohistochemistry for factor VS. The tumor volume was calculated and lung metastatic nodules were counted. Results : The heparanase expression, MVD, tumor volume and lung metastatic nodules in AS-ODN treated group were significantly decreased compared with that in NS-ODN treated group and that in PBS group (P〈0.01). Conclusion : Heparanase AS-ODN has significant inhibitory effect on the angiogenesis and metastasis of human mammary carcinoma cell xenografts in nude mice.展开更多
A middle size experiental wave generator has been implemented is the Ujikawa Open Laboratory, Disaster Prevention Research Institute, Kyoto University. The generator is composed of a pistontype wave maker, a head stra...A middle size experiental wave generator has been implemented is the Ujikawa Open Laboratory, Disaster Prevention Research Institute, Kyoto University. The generator is composed of a pistontype wave maker, a head strage water tank and a current generator to mainly reproduce long waves like tsunami and storm surge. The paper desribes several experimental series to predict the applicability of the generator to model tests. The three operating sysemes are capable to be controlled in one operating sysytem and start time is contorolled separately according with the target tsunami and storm surge profiles. A sharp tsunami profile is reproduced in adjusting the start timing of piston type wave maker and opening gates of head storage tunk. Any type of tsunami waves are reproduced in the generator and it becomes a storong tool to predict the effective of"resiliency" of hardwares.展开更多
"Mass entrepreneurship and innovation" as become the new engine of China's economic development. In this paper, based on the policy network theory, to conduct the thorough research to the college students' innovat..."Mass entrepreneurship and innovation" as become the new engine of China's economic development. In this paper, based on the policy network theory, to conduct the thorough research to the college students' innovative undertaking policy in yunnan province, and connecting with the present situation of college students' innovative undertaking in yunnan, through to explain the framework For the college students' innovative undertaking policy change for empirical analysis. In order to further promote the innovation and entrepreneurship of yuunan university students, it also needs to solve the problems of policy overlap, reintroduction, light execution, and long management.展开更多
The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few sp...The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few species have been studied under well-controlled laboratory conditions. In this work, the effects of temperature and photoperiod on gonad development and spawning of Cephalothrix hongkongiensis were observed by rearing worms under different temperatures and photoperiods. Worms reared at 4~C and 6~C showed no growth or gonadal development, and all died within 109 days. At 8~C and 12~C, gonads could be seen from 90 days to the termination of the 360-day experiment, but no spawning was observed. Worms maintained at 16, 24, and 28~C showed both gonadal development and spawning, and matured faster at higher temperatures. Under a fixed temperature (16℃), photoperiod did not have any significant impact on maturation and spawning. It is likely that temperature plays a major role in regulating the maturation and reproductive cycle of C. hongkongiensis.展开更多
This paper uses empirical data to examine the issue of fairness of higher education student financial aid in China, noting different levels of regional economic development as the reason to explain the wide differ...This paper uses empirical data to examine the issue of fairness of higher education student financial aid in China, noting different levels of regional economic development as the reason to explain the wide differences in available financial resources for student aid. Government efforts aimed at reducing the gap in recent years is discussed.展开更多
Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly,...Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly, glycerol can generate environmental impact. One of the promises, the application of the crude glycerol is the production of citric acid by microbial fermentation. Citric acid is industrially produced by a submerged fermentation process with Aspergillus niger, using sucrose as carbon source, but due to increased demand for citric acid, alternative processes using renewable sources or waste materials as substrates and the cultivation of yeast strains are being studied. The aim of the study was to determine the best culture condition for maximum citric acid synthesis and lower isocitric acid production from crude glycerol through experimental design tool. For this purpose, the yeast strain Yarrowia lipolytica IMUFRJ-50682 was cultivated in nitrogen-limited glycerol-based media. Therefore, glycerol and yeast extract concentrations and agitation speed were evaluated as independent variables. With pure glycerol, the highest citric acid production achieved was 16.5 g/L with an isocitric acid production of 7.7% (in relation to citric acid). With crude glycerol, citric acid production reduced to 6.7 g/L because of higher biomass yield. Therefore, an increase in the initial carbon to nitrogen molar ratio from 714 to 1,561 was necessary to increase citric acid production to 9.2 g/L, reducing isocitric acid production and to achieve a yield of 0.41 g of citric acid per glycerol consumed. In this condition, less nitrogen source was used, reducing production costs.展开更多
Generative resources are mainly derived from the students (sometimes from the teachers), which is dynamically generated in the students' practice, self-inquiry, and cooperative communication. Gifted children refer ...Generative resources are mainly derived from the students (sometimes from the teachers), which is dynamically generated in the students' practice, self-inquiry, and cooperative communication. Gifted children refer to a group of children who have such characteristics as high IQ (intelligence quotient), strong creativity, and good personality. Their intelligence and capability have great potential for further development. As cognitive ability is one of the prominent characteristics of supernormal children, the lecturers can not only pay attention to teaching knowledge (facts teaching), but also need provide proper opportunities for them to develop their aggressiveness, creativities, and challenges when teaching these children. Because students are active in thinking, in the classroom, students often have some unexpected ideas, that is, the generation of the classroom, in the face of this situation, teachers should be how to do? A joke between students in the class, sparked the interest of a classmate, and then under the teachers' guidance, they invented a chemistry experiment instrument Ω type pipe, illustrated the importance of the teachers focus on creating teaching.展开更多
基金Supported by the National iqatural Science Foundation of China (20606023, 20490203).
文摘Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma generators can match the system best.A higher power input can always bring a higher conversion,but the selectivity to C2H6 decreased from 52.48% to 39.43% as the power increased from 20W to 49W.When discharge distance was 4mm,selectivities to almost all main products reached the max.The inner electrode made of stainless steel and the outer electrode with aluminum foil were one of the best options which can obviously enhance the conversion of methane.A larger flow rate always resulted in a lower conversion of methane.In the most time,19.93% steam promoted conversion of methane.
基金Supported by the Double Branch Plan of Sichuan Agricultural University(Nos.03571421,03571779)
文摘Laboratory-reared Schizothorax davidi larvae and juveniles were examined to assess the formation and characteristics of David’s schizothoracin otoliths.Otolith development was observed and their formation period was verifi ed by monitoring larvae and juveniles of knownage.The results revealed that lapilli and sagittae developed before hatching,and the first otolith increment was identified at 2 days post hatching in both.The shape of lapilli was relatively stable during development compared with that of sagittae;however,growth of four sagittae and lapilli areas was consistent,but the posterior area grew faster than the anterior area and the ventral surface grew faster than the dorsal surface.Similarly,the sum length of the radius of the anterior and posterior areas on sagittae and lapilli were linearly and binomially related to total fish length,respectively.Moreover,daily deposition rates were validated by monitoring knownage larvae and juveniles.The increase in lapilli width was 1.88±0.080 0μm at the ninth increment,which reached a maximum and the decreased gradually toward the otolith edge,whereas that of sagittae increased more slowly.These results illustrate the developmental biology of S.davidi,which will aid in population conservation and fish stock management.
文摘Objective: To study the perfusion CT features of rabbit VX2 brain tumor with correlation to MVD and VEGF, and to validate perfusion CT for reflection of tumor angiogenesis. Methods: Rabbit VX2 brain tumor model was established by injection of 100 μL viable tumor cells (10qmL) through a 2 mm-hole 5 mm to the right of the sagittal suture and 5 mm posterior to the coronal suture bored by dental drill. MRI was performed every 2 days after seven days of implantation to evaluate the growth of the tumor. Twenty New Zealand White rabbits with tumor size over 3 mm in diameter were randomly divided into 2 groups according to the tumor growth time with those less than 3 weeks as group 1 and those more than 3 weeks as group 2, and perfusion CT were performed accordingly. CT measurements of BV, BF and PS from tumor, peritumor and contralateral normal tissue regions were obtained. After that the animals were sacrificed and 2% Evans blue (2 mL/kg) was given intravenously in 16 of these animals 1 h prior to sacrifice to detect breakdown of the blood brain barrier. VEGF and MVD were evaluated in immunohistochemical examination of the specimens. Results: Tumor had significantly higher BV, BF and PS (P=0.000) than peritumor and normal tissue region. Tumor BV, BF and MVD in group 2 were significantly higher than that in group 1 (P〈0.01). Significant linear correlation was found between MVD and BV (t=-0.915, P=-0.000), MVD and BF (t=0.901, P=-0.000), and MVD and PS (t=-0.459, P=0.042). We also found a rank correlation between PS and blue stain of tumor (rs=0.861, P=0.000). Conclusion: Perfusion CT can distinguish tumor from peritumor and normal tissue clearly, reflect tumor angiogenesis accurately, and provide useful information for the evaluation of brain tumor.
文摘Objective: To explore the possibility of the transfection of MyoD gene induced bone marrow mesenchymal stem cells ( MSCs) to differentiate into myoblasts in vitro. Methods: The eukaryotic expression plasmid vector pIRES2-EGFP-MyoD was transfected into MSCs with lipotransfection method, and the positive cells were selected by G418; The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified, purified product was identified by sequencing; The reporter gene enhanced green fluorescence protein ( EFGP) was observed in the transfected cells under a fluorescent and a laser confocal microscopes; Immunohistochemical methods was used to examine the expressions of MyoD, myogenin, myosin, myoglobin and desmin in the differentiated cells. The ultrastructure changes of the cells before and after transfection were observed with electron microscopy. Results: The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified, purified product was as same in sequence as that from Genbank; Green fluorescence was observed in the transfected cells under a fluorescent and a laser confocal microscopes; Immunohistochemical methods indicated that MyoD, myogenin, myosin, myoglobin and desmin were expressed in the transfected cells; The transfected cells showed the morphological characteristics of mature cells with filaments in their cytoplasm. Conclusion: MyoD gene can induce cultured MSCs to successfully differentiate into myoblasts , probably providing an experimental foundation for trauma repair.
文摘Objective: To evaluate the inhibitory effect of heparanase antisense oligodeoxynucleotide (AS-ODN) on the angiogenesis and metastasis of human mammary carcinoma cell xenografts in nude mice. Methods: The AS-ODN complementary to the start codon region of heparanase mRNA and its control, scrambled nonsense oligodeoxynucleotide (NS-ODN) were designed and synthesized. A subcutaneous growth model and an acute hematogenous metastasis model of human mammary carcinoma were established in nude mice and were treated with ODNs. The heparanase expression in tumor was evaluated by RT-PCR and Western blot. The microvessel density (MVD) was measured by immunohistochemistry for factor VS. The tumor volume was calculated and lung metastatic nodules were counted. Results : The heparanase expression, MVD, tumor volume and lung metastatic nodules in AS-ODN treated group were significantly decreased compared with that in NS-ODN treated group and that in PBS group (P〈0.01). Conclusion : Heparanase AS-ODN has significant inhibitory effect on the angiogenesis and metastasis of human mammary carcinoma cell xenografts in nude mice.
文摘A middle size experiental wave generator has been implemented is the Ujikawa Open Laboratory, Disaster Prevention Research Institute, Kyoto University. The generator is composed of a pistontype wave maker, a head strage water tank and a current generator to mainly reproduce long waves like tsunami and storm surge. The paper desribes several experimental series to predict the applicability of the generator to model tests. The three operating sysemes are capable to be controlled in one operating sysytem and start time is contorolled separately according with the target tsunami and storm surge profiles. A sharp tsunami profile is reproduced in adjusting the start timing of piston type wave maker and opening gates of head storage tunk. Any type of tsunami waves are reproduced in the generator and it becomes a storong tool to predict the effective of"resiliency" of hardwares.
文摘"Mass entrepreneurship and innovation" as become the new engine of China's economic development. In this paper, based on the policy network theory, to conduct the thorough research to the college students' innovative undertaking policy in yunnan province, and connecting with the present situation of college students' innovative undertaking in yunnan, through to explain the framework For the college students' innovative undertaking policy change for empirical analysis. In order to further promote the innovation and entrepreneurship of yuunan university students, it also needs to solve the problems of policy overlap, reintroduction, light execution, and long management.
基金Supported by the National Natural Science Foundation of China(Nos.30970333,31172046)
文摘The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few species have been studied under well-controlled laboratory conditions. In this work, the effects of temperature and photoperiod on gonad development and spawning of Cephalothrix hongkongiensis were observed by rearing worms under different temperatures and photoperiods. Worms reared at 4~C and 6~C showed no growth or gonadal development, and all died within 109 days. At 8~C and 12~C, gonads could be seen from 90 days to the termination of the 360-day experiment, but no spawning was observed. Worms maintained at 16, 24, and 28~C showed both gonadal development and spawning, and matured faster at higher temperatures. Under a fixed temperature (16℃), photoperiod did not have any significant impact on maturation and spawning. It is likely that temperature plays a major role in regulating the maturation and reproductive cycle of C. hongkongiensis.
文摘This paper uses empirical data to examine the issue of fairness of higher education student financial aid in China, noting different levels of regional economic development as the reason to explain the wide differences in available financial resources for student aid. Government efforts aimed at reducing the gap in recent years is discussed.
文摘Due to the scarcity of fossil fuels in the world, there is increasing interest in the commercial production of biodiesel, which leads to obtaining large amounts of glycerol as a byproduct. If not disposed of properly, glycerol can generate environmental impact. One of the promises, the application of the crude glycerol is the production of citric acid by microbial fermentation. Citric acid is industrially produced by a submerged fermentation process with Aspergillus niger, using sucrose as carbon source, but due to increased demand for citric acid, alternative processes using renewable sources or waste materials as substrates and the cultivation of yeast strains are being studied. The aim of the study was to determine the best culture condition for maximum citric acid synthesis and lower isocitric acid production from crude glycerol through experimental design tool. For this purpose, the yeast strain Yarrowia lipolytica IMUFRJ-50682 was cultivated in nitrogen-limited glycerol-based media. Therefore, glycerol and yeast extract concentrations and agitation speed were evaluated as independent variables. With pure glycerol, the highest citric acid production achieved was 16.5 g/L with an isocitric acid production of 7.7% (in relation to citric acid). With crude glycerol, citric acid production reduced to 6.7 g/L because of higher biomass yield. Therefore, an increase in the initial carbon to nitrogen molar ratio from 714 to 1,561 was necessary to increase citric acid production to 9.2 g/L, reducing isocitric acid production and to achieve a yield of 0.41 g of citric acid per glycerol consumed. In this condition, less nitrogen source was used, reducing production costs.
文摘Generative resources are mainly derived from the students (sometimes from the teachers), which is dynamically generated in the students' practice, self-inquiry, and cooperative communication. Gifted children refer to a group of children who have such characteristics as high IQ (intelligence quotient), strong creativity, and good personality. Their intelligence and capability have great potential for further development. As cognitive ability is one of the prominent characteristics of supernormal children, the lecturers can not only pay attention to teaching knowledge (facts teaching), but also need provide proper opportunities for them to develop their aggressiveness, creativities, and challenges when teaching these children. Because students are active in thinking, in the classroom, students often have some unexpected ideas, that is, the generation of the classroom, in the face of this situation, teachers should be how to do? A joke between students in the class, sparked the interest of a classmate, and then under the teachers' guidance, they invented a chemistry experiment instrument Ω type pipe, illustrated the importance of the teachers focus on creating teaching.