Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of...Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of the normalized response spectra (NRS) of ground motions, respectively. Engineering characteristics of 5% -damped NRS, and the bi-normalized response spectra (BNRS) are investigated accounting for the effects of soil condition and fault distance. Nearly 600 horizontal ground motion components during the Chi-Chi earthquake are included in the analysis. It shows that the NRS strongly depends on soil condition and fault distance. However, soil condition and distance have only a slight influence on two kinds of BNRS. Dispersion analysis indicates that such normalization can reduce scatter in the derivation of response spectral shapes. Finally, a parametric analysis of the scalar periods (Tp, To) is performed and then compared with those of previous studies. These special and particular aspects of earthquake response spectra and scalar periods need to be considered in developing earthquake-resistant design criteria.展开更多
A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on ...A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products.展开更多
Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These...Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These powders were proved nanopaticles by transmission electron microscope. The effects on proliferation of periodontal ligament cell(PDLC) were observed in vitro with MTT [3-(4,5dimethylthiazo;-2-yl)-2,5-diphenytetralium bromide] method. Results: On the 2nd,3rd,4th day after treated with nanoparticles of hydroxyapatite, the proliferate activity of the PDLC increases significantly, compared with those with dense hydroxyaoatite and control but no significant difference could be found between the dense hydroxyapatite and the control. Conclusion: Nanophase hydroxyapatite can promote the regeneration of periodontal tissue.展开更多
The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annua...The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance.展开更多
Objective: To investigate the p21WAF1 /CIP1gene DNA sequence change and their relationship with the phenotype of human osteosarcoma. Methods: p21WAF1 /CIP1gene DNA of 36 osteosarcoma spec- ...Objective: To investigate the p21WAF1 /CIP1gene DNA sequence change and their relationship with the phenotype of human osteosarcoma. Methods: p21WAF1 /CIP1gene DNA of 36 osteosarcoma spec- imens was examined by using polymerase chain reaction-single strand conformation polymorphism (PCR- SSCP) method. The PCR products were sequenced directly. Results: In p21WAF1 /CIP1 gene exon3 of 36 cases of human osteosarcoma, the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 17 cases with the incidence being 44.4%. In 10 normal blood samples, DNA sequence analysis showed the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 8 cases with the incidence being 80%. Conclusion: The novel location of p21WAF1 /CIP1gene polymorphism of osteosarcoma, but not mutation was de?ned, and this location might provide the meaningful reference for the further research of p21WAF1/CIP1 gene.p2lWAF1/CIP1基因DNA序列分析及其与骨肉瘤表型的关系展开更多
Background: Research interest in both partnered Latin dance and non-partnered Latin-themed aerobic dance has increased in recent years, likely a result of the gaining popularity of these types of instructor-led group...Background: Research interest in both partnered Latin dance and non-partnered Latin-themed aerobic dance has increased in recent years, likely a result of the gaining popularity of these types of instructor-led group classes among the mainstream dance and fitness audiences; however, the efficacy of these activities for the purposes of health promotion currently remains unclear. The purpose of this study was to simultaneously assess the physiological responses and psychological experiences during salsa dance and Zumba fitness in a community sample of physically inactive women. Methods: Twenty-four participants, aged 22-56 years, visited the laboratory to perform a graded exercise test for determination of maximal oxygen uptake and maximal heart rate. The participants then attended 2 partnered salsa dance and 2 non-partnered Zumba fitness classes each in a counterbalanced order over a 2-week period. The 1-h classes were taught by certified instructors in established venues in the Royal Borough of Kingston and the surrounding communities of London, UK. Physiological data were collected using a wrist-worn ActiGraph wGT3X+ acceler- ometer with accompanying heart rate monitor and were processed using previously validated dance-specific techniques. Psychological experiences were measured via the Subjective Exercise Experiences Scale. Results: There was a significantly higher (p 〈 0.001) total time spent in moderate-to-vigorous physical activity (51.2± 3.1 vs. 32.6 ±5.9 min), total energy expenditure (411±66 vs. 210 ± 46 kcal), and total step count (6773 ± 556 vs. 4108 ±781 steps) during Zumba fitness when compared to salsa dance. Significant pre- to post-class improvements in positive well-being (p 〈 0.01, partial 7/2 = 0.4l) and psychological distress (p 〈 0.001, partial 02 = 0.72) were simultaneously observed for both salsa dance and Zumba fitness. Conclusion: The acute responses to classes of partnered Latin dance and non-partnered Latin-themed aerobic dance suggest that in physically inactive women participation is indeed efficacious in terms of community-based physical activity and psychosocial health promotion.展开更多
Friction stir welding (FSW) of 6061 aluminium alloy butt joint was carried out at each rotation speed of 600, 800, 1000, 1200 r/min for two different travel speeds, 80 and 100 mm/min, at a constant probe depth of 1....Friction stir welding (FSW) of 6061 aluminium alloy butt joint was carried out at each rotation speed of 600, 800, 1000, 1200 r/min for two different travel speeds, 80 and 100 mm/min, at a constant probe depth of 1.85 mm. The calculated energy input based on the FSW parameters studied shows that the ultimate tensile strength (UTS) of the butt joint is obtained within a certain range of energy input of 297 kJ to 354 kJ out of total range of energy input studied from 196 kJ to 405 kJ. The fatigue behaviors of high-strength and low-strength joints performed at different stress ratios, i.e., 0.5, 0.3, 0.1, -0.3, -0.5, indicate that the fatigue behaviors of both the welds are sensitive to the microstructural features, such as stir zone (SZ), thermo mechanically affected zone (TMAZ) and heat affected zone (HAZ). The observed fatigue strengths were discussed in terms of the microstructure, crack path behavior and fracture surface.展开更多
Objective: To explore the influence of perioperative blood transfusion on the postoperative survival of patients with colon cancer. Methods: Univariate and multivariate retrospective analyses were performed on the s...Objective: To explore the influence of perioperative blood transfusion on the postoperative survival of patients with colon cancer. Methods: Univariate and multivariate retrospective analyses were performed on the survival in a total of 723 colon cancer patients which were treated surgically during a period of 10 years. Results: Kaplan-Meier estimates showed that more than 800 mL perioperative blood transfusion was the survival predictor. Blood transfusion influenced significantly the prognosis of patients 40 years old and younger, those undergoing helicoloectomy left side, those with papillary adenocarcinoma, those with big tumors (diameter ≥ 8 cm), those with stage Ⅰ tumors, those with lymphatic node metastases and those without liver metastases. In multivariate analysis only the tumor location, radicality of operation, lymphatic invasion, liver metastasis, depth of tumor invasion and TNM stage retained their significance. Conclusion: Perioperative blood transfusion is some extent. The indication of blood transfusion the prognostic factor for patients with colon cancer to must be restricted strictly, specially in patients younger than 40 years old, with right side lesion, papillary adenocarcinoma, big tumors (diameter ≥8 cm), stage Ⅰ tumors and lymphatic node metastases or without liver metastases. But perioperative blood transfusion may not be deleterious for patients with staging Ⅳ disease and with distant metastases.展开更多
Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulati...Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulation model, using system dy- namics methodology, to assess the sustainable performance of projects. Three major factors are used to examine project sus- tainable performance (PSP): the sustainability of economic development (E), the sustainability of social development (S), and the sustainability of environmental development (En). Sustainable development ability (SDA) was used as a prototype to evaluate the degree of sustainable performance. The simulation software ‘ithink’ was used to help with the application of the model to a real life case. This paper explains and demonstrates the procedures used to develop the model and finally offers an approach for assessing the feasibility of a construction project in terms of its sustainable performance.展开更多
The damage tolerance for pipe/rod bar in the auxiliary power units (APUs) support system is studied. The main objective is to study whether planes can safely land when the fatigue crack appears on the bar. Firstly, ...The damage tolerance for pipe/rod bar in the auxiliary power units (APUs) support system is studied. The main objective is to study whether planes can safely land when the fatigue crack appears on the bar. Firstly, the stress intensity factors (K~) of two bar structures are computed, and the iso-stress intensity factor (iso-Kl) model is presented. The model uses the finite element model (FEM) instead of the parameters of material to com- pute the crack propagation. Then, the general relations between Kt vs crack size are obtained for different mate- rials, inner to outer diameter ratios (D^n/Dout) and external crack propagation angles (0). Finally, the FEM anal- ysis results are input to the ANSYS parametric design language(ANSYS-APDL) software. And the fatigue life of damaged bar is estimated under the condition of loading spectrum.展开更多
For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intr...For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune factors such as antibody then played important role in response to anti-infection at the latter stage.展开更多
AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter ...AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter of the perioperative course and long-term prognosis in patients with squamous cell carcinoma and aclenocarcinoma of the oesophagus. METHODS: Serum CRP was determined preoperatively in 291 of 371 patients undergoing oesophagectomy for cancer from December 1989 to March 2004. Median patient age was 59 (28-79) year, 82.5% of patients were males. Squamous cell carcinoma was diagnosed in 151 (51.9%) and aclenocarcinoma in 122 patients. Transhiatal oesophagectomy was clone in 151 (51.9%) patients and 134 (46.0%) patients underwent the abclominothoracic procedure. RESULTS: In 127 (43.6%) patients the preoperative serum CRP concentration was within the normal range (〈 5 mg/clL), elevated CRP levels were measured in 164 (56.4%) patients. Tumour extension (P 〈 0.0005) and the number of lymph nodes affected by metastatic spread (P = 0.015) were significantly increased in the group with elevated CRP levels. Among the perioperative parameters both the number of blood transfusions (P = 0.006) and the general complication rate (P = 0.002) were higher in patients with elevated preoperative CRP levels. The long-term survival rate of 13.6 (0-109.8) mo was poorer in the group with elevated CRP levels compared to 18.9 (0-155.4) mo in the group with normal CRP levels (log-rank test: P = 0.107). Multivariateanalysis with backward variables selection identified preoperative CRP as an independent prognostic factor of the long-term prognosis in patients with oesophageal carcinoma, with a hazard ratio of 1.182 (95% confidence interval: 1.030-1.356). CONCLUSION: The preoperative serum CRP-level is an easily determined independent prognostic marker in patients with squamous cell carcinoma and adenocarcinoma of the oesophagus.展开更多
The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on metha...The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the'square ways show that the better'average performance was obtainedwith the square way.展开更多
This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find t...This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find the optimal delay time for production and production time sequentially. It is found that the optimal delay time for production and the production time are not static, but dynamic and variant with time. It is important for a manufacturer to schedule the production so as to prevent facilities and workers from idling.展开更多
A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation...A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation of the generalized model was given. Simulations were conducted with different power values. The results show that the solution of the generalized equation is a periodic function. The expressions of the amplitude and the period(frequency) of the generalized equation were derived by the physical method. All the simulation results coincide with the calculation results of the derived expressions. A special function also was deduced and proven to be convergent in the theoretical analysis. The limit value of the special function also was derived. The generalized model can be used in solving a type of differential equation and to generate periodic waveforms.展开更多
基金China Postdoctoral Science Foundation ( No20060400826)
文摘Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of the normalized response spectra (NRS) of ground motions, respectively. Engineering characteristics of 5% -damped NRS, and the bi-normalized response spectra (BNRS) are investigated accounting for the effects of soil condition and fault distance. Nearly 600 horizontal ground motion components during the Chi-Chi earthquake are included in the analysis. It shows that the NRS strongly depends on soil condition and fault distance. However, soil condition and distance have only a slight influence on two kinds of BNRS. Dispersion analysis indicates that such normalization can reduce scatter in the derivation of response spectral shapes. Finally, a parametric analysis of the scalar periods (Tp, To) is performed and then compared with those of previous studies. These special and particular aspects of earthquake response spectra and scalar periods need to be considered in developing earthquake-resistant design criteria.
文摘A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products.
文摘Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These powders were proved nanopaticles by transmission electron microscope. The effects on proliferation of periodontal ligament cell(PDLC) were observed in vitro with MTT [3-(4,5dimethylthiazo;-2-yl)-2,5-diphenytetralium bromide] method. Results: On the 2nd,3rd,4th day after treated with nanoparticles of hydroxyapatite, the proliferate activity of the PDLC increases significantly, compared with those with dense hydroxyaoatite and control but no significant difference could be found between the dense hydroxyapatite and the control. Conclusion: Nanophase hydroxyapatite can promote the regeneration of periodontal tissue.
文摘The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance.
文摘Objective: To investigate the p21WAF1 /CIP1gene DNA sequence change and their relationship with the phenotype of human osteosarcoma. Methods: p21WAF1 /CIP1gene DNA of 36 osteosarcoma spec- imens was examined by using polymerase chain reaction-single strand conformation polymorphism (PCR- SSCP) method. The PCR products were sequenced directly. Results: In p21WAF1 /CIP1 gene exon3 of 36 cases of human osteosarcoma, the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 17 cases with the incidence being 44.4%. In 10 normal blood samples, DNA sequence analysis showed the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 8 cases with the incidence being 80%. Conclusion: The novel location of p21WAF1 /CIP1gene polymorphism of osteosarcoma, but not mutation was de?ned, and this location might provide the meaningful reference for the further research of p21WAF1/CIP1 gene.p2lWAF1/CIP1基因DNA序列分析及其与骨肉瘤表型的关系
文摘Background: Research interest in both partnered Latin dance and non-partnered Latin-themed aerobic dance has increased in recent years, likely a result of the gaining popularity of these types of instructor-led group classes among the mainstream dance and fitness audiences; however, the efficacy of these activities for the purposes of health promotion currently remains unclear. The purpose of this study was to simultaneously assess the physiological responses and psychological experiences during salsa dance and Zumba fitness in a community sample of physically inactive women. Methods: Twenty-four participants, aged 22-56 years, visited the laboratory to perform a graded exercise test for determination of maximal oxygen uptake and maximal heart rate. The participants then attended 2 partnered salsa dance and 2 non-partnered Zumba fitness classes each in a counterbalanced order over a 2-week period. The 1-h classes were taught by certified instructors in established venues in the Royal Borough of Kingston and the surrounding communities of London, UK. Physiological data were collected using a wrist-worn ActiGraph wGT3X+ acceler- ometer with accompanying heart rate monitor and were processed using previously validated dance-specific techniques. Psychological experiences were measured via the Subjective Exercise Experiences Scale. Results: There was a significantly higher (p 〈 0.001) total time spent in moderate-to-vigorous physical activity (51.2± 3.1 vs. 32.6 ±5.9 min), total energy expenditure (411±66 vs. 210 ± 46 kcal), and total step count (6773 ± 556 vs. 4108 ±781 steps) during Zumba fitness when compared to salsa dance. Significant pre- to post-class improvements in positive well-being (p 〈 0.01, partial 7/2 = 0.4l) and psychological distress (p 〈 0.001, partial 02 = 0.72) were simultaneously observed for both salsa dance and Zumba fitness. Conclusion: The acute responses to classes of partnered Latin dance and non-partnered Latin-themed aerobic dance suggest that in physically inactive women participation is indeed efficacious in terms of community-based physical activity and psychosocial health promotion.
文摘Friction stir welding (FSW) of 6061 aluminium alloy butt joint was carried out at each rotation speed of 600, 800, 1000, 1200 r/min for two different travel speeds, 80 and 100 mm/min, at a constant probe depth of 1.85 mm. The calculated energy input based on the FSW parameters studied shows that the ultimate tensile strength (UTS) of the butt joint is obtained within a certain range of energy input of 297 kJ to 354 kJ out of total range of energy input studied from 196 kJ to 405 kJ. The fatigue behaviors of high-strength and low-strength joints performed at different stress ratios, i.e., 0.5, 0.3, 0.1, -0.3, -0.5, indicate that the fatigue behaviors of both the welds are sensitive to the microstructural features, such as stir zone (SZ), thermo mechanically affected zone (TMAZ) and heat affected zone (HAZ). The observed fatigue strengths were discussed in terms of the microstructure, crack path behavior and fracture surface.
文摘Objective: To explore the influence of perioperative blood transfusion on the postoperative survival of patients with colon cancer. Methods: Univariate and multivariate retrospective analyses were performed on the survival in a total of 723 colon cancer patients which were treated surgically during a period of 10 years. Results: Kaplan-Meier estimates showed that more than 800 mL perioperative blood transfusion was the survival predictor. Blood transfusion influenced significantly the prognosis of patients 40 years old and younger, those undergoing helicoloectomy left side, those with papillary adenocarcinoma, those with big tumors (diameter ≥ 8 cm), those with stage Ⅰ tumors, those with lymphatic node metastases and those without liver metastases. In multivariate analysis only the tumor location, radicality of operation, lymphatic invasion, liver metastasis, depth of tumor invasion and TNM stage retained their significance. Conclusion: Perioperative blood transfusion is some extent. The indication of blood transfusion the prognostic factor for patients with colon cancer to must be restricted strictly, specially in patients younger than 40 years old, with right side lesion, papillary adenocarcinoma, big tumors (diameter ≥8 cm), stage Ⅰ tumors and lymphatic node metastases or without liver metastases. But perioperative blood transfusion may not be deleterious for patients with staging Ⅳ disease and with distant metastases.
基金Project supported by the Research Grant Council of Hong Kong,China
文摘Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulation model, using system dy- namics methodology, to assess the sustainable performance of projects. Three major factors are used to examine project sus- tainable performance (PSP): the sustainability of economic development (E), the sustainability of social development (S), and the sustainability of environmental development (En). Sustainable development ability (SDA) was used as a prototype to evaluate the degree of sustainable performance. The simulation software ‘ithink’ was used to help with the application of the model to a real life case. This paper explains and demonstrates the procedures used to develop the model and finally offers an approach for assessing the feasibility of a construction project in terms of its sustainable performance.
文摘The damage tolerance for pipe/rod bar in the auxiliary power units (APUs) support system is studied. The main objective is to study whether planes can safely land when the fatigue crack appears on the bar. Firstly, the stress intensity factors (K~) of two bar structures are computed, and the iso-stress intensity factor (iso-Kl) model is presented. The model uses the finite element model (FEM) instead of the parameters of material to com- pute the crack propagation. Then, the general relations between Kt vs crack size are obtained for different mate- rials, inner to outer diameter ratios (D^n/Dout) and external crack propagation angles (0). Finally, the FEM anal- ysis results are input to the ANSYS parametric design language(ANSYS-APDL) software. And the fatigue life of damaged bar is estimated under the condition of loading spectrum.
基金Supported by the National High Technology Research and Development Program of China (863 program, No. 2007AA09Z115)Technology Program of Xiamen (No. 3502Z73019)
文摘For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune factors such as antibody then played important role in response to anti-infection at the latter stage.
文摘AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter of the perioperative course and long-term prognosis in patients with squamous cell carcinoma and aclenocarcinoma of the oesophagus. METHODS: Serum CRP was determined preoperatively in 291 of 371 patients undergoing oesophagectomy for cancer from December 1989 to March 2004. Median patient age was 59 (28-79) year, 82.5% of patients were males. Squamous cell carcinoma was diagnosed in 151 (51.9%) and aclenocarcinoma in 122 patients. Transhiatal oesophagectomy was clone in 151 (51.9%) patients and 134 (46.0%) patients underwent the abclominothoracic procedure. RESULTS: In 127 (43.6%) patients the preoperative serum CRP concentration was within the normal range (〈 5 mg/clL), elevated CRP levels were measured in 164 (56.4%) patients. Tumour extension (P 〈 0.0005) and the number of lymph nodes affected by metastatic spread (P = 0.015) were significantly increased in the group with elevated CRP levels. Among the perioperative parameters both the number of blood transfusions (P = 0.006) and the general complication rate (P = 0.002) were higher in patients with elevated preoperative CRP levels. The long-term survival rate of 13.6 (0-109.8) mo was poorer in the group with elevated CRP levels compared to 18.9 (0-155.4) mo in the group with normal CRP levels (log-rank test: P = 0.107). Multivariateanalysis with backward variables selection identified preoperative CRP as an independent prognostic factor of the long-term prognosis in patients with oesophageal carcinoma, with a hazard ratio of 1.182 (95% confidence interval: 1.030-1.356). CONCLUSION: The preoperative serum CRP-level is an easily determined independent prognostic marker in patients with squamous cell carcinoma and adenocarcinoma of the oesophagus.
基金supported in part by the University of Sétif,and the Ministry of Higher Education and Scientific Research (Algeria) with Project No.E01220080023
文摘The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the'square ways show that the better'average performance was obtainedwith the square way.
基金Funded by National Social Sciences Fund for Young Scholar ( No.020JY027)
文摘This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find the optimal delay time for production and production time sequentially. It is found that the optimal delay time for production and the production time are not static, but dynamic and variant with time. It is important for a manufacturer to schedule the production so as to prevent facilities and workers from idling.
基金Funded by the National Natural Science Foundation of China (No. 50375113).
文摘A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation of the generalized model was given. Simulations were conducted with different power values. The results show that the solution of the generalized equation is a periodic function. The expressions of the amplitude and the period(frequency) of the generalized equation were derived by the physical method. All the simulation results coincide with the calculation results of the derived expressions. A special function also was deduced and proven to be convergent in the theoretical analysis. The limit value of the special function also was derived. The generalized model can be used in solving a type of differential equation and to generate periodic waveforms.