The microbial potential of Penicillium has received critical attention.The present research aimed to elucidate the efficacy of crude enzyme secreted from Penicillium oxalicum WX-209 in degrading citrus segments and ev...The microbial potential of Penicillium has received critical attention.The present research aimed to elucidate the efficacy of crude enzyme secreted from Penicillium oxalicum WX-209 in degrading citrus segments and evaluate the safety of the process.Results showed that citrus segment membranes gradually dissolved after treatment with the crude enzyme solution,indicating good degradation capability.No significant differences in body weight,food ingestion rate,hematology,blood biochemistry,and weight changes of different organs were found between the enzyme intake and control groups.Serial experiments showed that the crude enzyme had high biological safety.Moreover,the whole genome of P.oxalicum WX-209 was sequenced by PacBio and Illumina platforms.Twenty-five scaffolds were assembled to generate 36 Mbp size of genome sequence comprising 11369 predicted genes modeled with a GC content of 48.33%.A total of 592 genes were annotated to encode enzymes related to carbohydrates,and some degradation enzyme genes were identified in strain P.oxalicum WX-209.展开更多
[Objectives]To observe the clinical efficacy and safety of Zhuang Medicine Xiaoyan Zhiyang Formula by retrospective analysis of clinical use.[Methods]A total of 225 cases were collected,including 117 males and 108 fem...[Objectives]To observe the clinical efficacy and safety of Zhuang Medicine Xiaoyan Zhiyang Formula by retrospective analysis of clinical use.[Methods]A total of 225 cases were collected,including 117 males and 108 females,115 cases of contact dermatitis and 110 cases of acute eczema.Zhuang Medicine Xiaoyan Zhiyang Formula was administered to 225 patients with contact dermatitis and acute eczema and the clinical efficacy was evaluated.[Results]After one week of treatment,among 225 patients with contact dermatitis and acute eczema,76 cases were cured(33.78%),133 cases showed marked response(59.11%),16 cases(7.11%)were improved,0 case was ineffective,and the overall response rate was 92.89%.After one week of Zhuang Medicine Xiaoyan Zhiyang Formula treatment,the symptoms of itching,pain and swelling were significantly improved in all patients,and the rash was partially crusted without new symptom,and there were no complications and adverse reactions.[Conclusions]Zhuang Medicine Xiaoyan Zhiyang Formula therapy has a remarkable effect in the treatment of contact dermatitis and acute eczema.展开更多
Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of ...Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of human umbilical cord mesenchymal stem cells(hu MSCs) before clinical application. In this study, hu MSCs were harvested from human amniotic membrane and umbilical cord vascular tissue. A rat model of TBI was established using the controlled cortical impact method. Starting from the third day after injury, the rats were injected with 10 μL of 5 × 10^(6)/m L hu MSCs by cerebral stereotaxis or with 500 μL of 1 × 10^(6)/m L hu MSCs via the tail vein for 3 successive days. hu MSC transplantation decreased the serum levels of proinflammatory cytokines in rats with TBI and increased the serum levels of anti-inflammatory cytokines, thereby exhibiting good immunoregulatory function. The transplanted hu MSCs were distributed in the liver, lung and brain injury sites. No abnormal proliferation or tumorigenesis was found in these organs up to 12 months after transplantation. The transplanted hu MSCs negligibly proliferated in vivo, and apoptosis was gradually observed at later stages. These findings suggest that hu MSC transplantation for the treatment of traumatic brain injury displays good safety. In addition, hu MSCs exhibit good immunoregulatory function, which can help prevent and reduce secondary brain injury caused by the rapid release of inflammatory factors after TBI. This study was approved by the Ethics Committee of Wuhan General Hospital of PLA(approval No. 20160054) on November 1, 2016.展开更多
The wheel-rail force measurement is of great importance to the condition monitoring and safety evaluation of railway vehicles. In this paper, an improved indirect method for wheel-rail force measurement is proposed to...The wheel-rail force measurement is of great importance to the condition monitoring and safety evaluation of railway vehicles. In this paper, an improved indirect method for wheel-rail force measurement is proposed to evaluate the running safety of railway vehicles. In this method, the equilibrium equations of a suspended wheelset are derived and the wheel-rail forces are then be obtained from measured suspension and inertia forces. This indirect method avoids structural modifications to the wheelset and is applicable to the long-term operation of railway vehicles. As the wheel-rail lateral forces at two sides of the wheelset are difficult to separate, a new derailment criterion by combined use of wheelset derailment coefficient and wheel unloading ratio is proposed. To illustrate its effectiveness, the indirect method is applied to safety evaluation of rail- way vehicles in different scenarios, such as the cross wind safety of a high-speed train and the safety of a metro vehicle with hunting motions. Then, the feasibility of using this method to identify wheel-rail forces for low-floor light rail vehicles with resilient wheels is discussed. The values identified by this method is compared with that by Simpack simulation for the same low-floor vehicle, which shows a good coincidence between them in the time domain of the wheelset lateral force and the wheel-rail vertical force. In addition, use of the method to determine the high-frequency wheel-rail interaction forces reveals that it is possible to identify the high-frequency wheel-rail forces through the accelerations on the axle box.展开更多
This paper describes a set of on-site earthquake safety evaluation systems for buildings, which were developed based on a network platform. The system embedded into the quantitative research results which were complet...This paper describes a set of on-site earthquake safety evaluation systems for buildings, which were developed based on a network platform. The system embedded into the quantitative research results which were completed in accordance with the provisions from Post-earthquake Field Works, Part 2: Safety Assessment of Buildings, GB18208.2 -2001, and was further developed into an easy-to-use software platform. The system is aimed at allowing engineering professionals, civil engineeing technicists or earthquake-affected victims on site to assess damaged buildings through a network after earthquakes. The authors studied the function structure, process design of the safety evaluation module, and hierarchical analysis algorithm module of the system in depth, and developed the general architecture design, development technology and database design of the system. Technologies such as hierarchical architecture design and Java EE were used in the system development, and MySQL5 was adopted in the database development. The result is a complete evaluation process of information collection, safety evaluation, and output of damage and safety degrees, as well as query and statistical analysis of identified buildings. The system can play a positive role in sharing expert post-earthquake experience and promoting safety evaluation of buildings on a seismic field.展开更多
A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of...A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of a one-machine and three-base system is proposed. The framework of the three-base system has been designed and the structural framework constructed in turn. A practical example is given to illustrate the process of using this system and it can be used for comparison and analysis purposes. The key technology of the system is its ability to reorganize and improve the expert system's knowledge base by establishing the expert system. This system utilizes the computer technology inference process, making safety evaluation conclusions more reasonable and applicable to the actual situation. The system is not only advanced, but also feasible, reliable, artificially intelligent, and has the capacity to constantly grow.展开更多
The objective of the present study was to evaluate potential adverse effects of diacylglycerol microemulsion (DAGM) in rats/mice. Acute safety evaluation was carried out by giving intragastrically with 20 mL 25% DAG...The objective of the present study was to evaluate potential adverse effects of diacylglycerol microemulsion (DAGM) in rats/mice. Acute safety evaluation was carried out by giving intragastrically with 20 mL 25% DAG kg-1 body weight of DAGM or water with two groups of mice. Chronic safety evaluation with 40 male and 40 female Sprague-Dawley rats was carried out by setting a control group and 3 different dose groups (n=10 male+10 female) administered with DAGM with 6.7, 10 and 20 mL kg-1 body weight per day. Relevant parameters of liver and kidney function and biochemistry were determined by standard methods at end point. Acute toxicity study revealed the maximum tolerated dose (MTD) of DAGM was 20 mL kg-1 body weight in mice. No death was observed at the dose of 20 mL kg-1 body weight per day. Chronic safety evaluation did not show significant changes on hematological, histopathologic, clinical, and biochemical tests when administered at levels of 6.7, 10 and 20 mL kg-1 body weight per day to rats for 30 d. No significant body weight changes were observed in different dosages in both male and female rats. Our results suggested that acute and chronic adverse effects were not observed in histology and clinical parameters in both mice and rats. The results suggested that DAGM is safe at the experimental levels.展开更多
Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact z...Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact zones of the Xiaowan ultra-high arch dam. The principles of monitoring layout and design are introduced in detail. Prototype monitoring shows that the increment of the interfacial compressive stress is much larger in the impoundment stage than in the regulating stage. The water pressure and time-effect are two main factors affeeting the interfacial stress. The time-effect is the key factor in the initial impoundment stage, and the water pressure is the key factor after impoundment. The contact properties are significantly improved by grouting. This study shows that there are three typical stages in the joint opening hydrographs, namely the compression stage, opening stage, and stable stage. There is a nonlinear relationship between the joint opening and temperature, which can be well described by the S-function. In conclusion, the reinforcement effect is satisfying, and the abutment is safe.展开更多
Seismic safety evaluation is a basic work for determining the seismic resistance requirements of major construc-tion projects. The effect, especially the economic effect of the seismic safety evaluation has been gener...Seismic safety evaluation is a basic work for determining the seismic resistance requirements of major construc-tion projects. The effect, especially the economic effect of the seismic safety evaluation has been generally con-cerned. The paper gives a model for estimating the effect of seismic safety evaluation and calculates roughly the economic effect of seismic safety evaluation with some examples.展开更多
A subacute toxicity study of a potent tetanus toxoid (250 Lf) was carried out in guinea pigs.The toxoid was injected subcutaneously at the nape of the neck at dose levels of 1.0, 1.5.and 2.0 ml in Groups Ⅱ. Ⅲ. and ...A subacute toxicity study of a potent tetanus toxoid (250 Lf) was carried out in guinea pigs.The toxoid was injected subcutaneously at the nape of the neck at dose levels of 1.0, 1.5.and 2.0 ml in Groups Ⅱ. Ⅲ. and Ⅳ, respectively.In the controls (Group Ⅰ) 2.0 ml of aluminum phosphate suspension was given in each injection.Periodic evaluations of body weight, food/water intake, general observable behavior, hematology.and blood chemistry in toxoid-injected guinea pigs were similar to those in control guinea pigs.Thus, the toxoid did not cause any side effects up to four times the dose proposed for humans.1990 Academic Press, Inc.展开更多
Mechanical characterization of steel frame structure after fire are ana- lyzed based on fire dynamics, heat transfer theory, structural mechanics, and finite element theory. We study the temperature characteristics an...Mechanical characterization of steel frame structure after fire are ana- lyzed based on fire dynamics, heat transfer theory, structural mechanics, and finite element theory. We study the temperature characteristics and mechanical prop- erties of steel flame structure under different fire locations and propose a safety evaluation method. We also analyze damage level of main flame components, maximum temperature of fire, thermal characteristics of flame components, fir- ing duration, etc. to provide useful information for fire resistance design of the steel frame structure and post-disaster safety evaluation.展开更多
Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strict...Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strictly regulated. Considering their popular use and increasing safety concerns, thorough evaluations of their efficacy and safety are warranted to protect consumers from potential adverse effects. Toxicity tests (acute, sub- acute and chronic) using animals are widely applied to evaulate adverse effects of a drug and thereby determine its "No Observed Adverse Effect Level" (NOAEL).展开更多
Eight trials, with 439 human volunteers who consumed irradiated foods including rice, potatoes, mushrooms, peanuts, and Chinese sausages, as well as diets composed of multiple irradiated foods (irradiated at dosages o...Eight trials, with 439 human volunteers who consumed irradiated foods including rice, potatoes, mushrooms, peanuts, and Chinese sausages, as well as diets composed of multiple irradiated foods (irradiated at dosages of 0.2 to 8 kGy) that accounted for 60-66% of the entire diet, were carried out for 2-3 months according to a unified protocol. No adverse effects on body weight, blood pressure, ECG, hematology, blood enzyme activities, serum lipids, or blood or urine 17-hydroxycortisol contents and no chromosomal aberration of peripheral blood lymphocytes were found. It is especially worthwhile to note that there was no change in the polyploidy after consumption of irradiated diets. On the basis of these results and a comprehensive analysis of the physical and chemical characteristics of irradiated foods, temporary hygienic standards for irradiated rice, potatoes, onions, garlic, Chinese sausages, peanuts, and mushrooms were promulgated by the Chinese Ministry of Public Health. 1989 Academic Press, Inc.展开更多
In an abnormal high-temperature fire environment,a structure with mechanical-thermal weak-link can be used to predict the permanent failure before the failure of some strong-links,such as explosive initiator,thus to p...In an abnormal high-temperature fire environment,a structure with mechanical-thermal weak-link can be used to predict the permanent failure before the failure of some strong-links,such as explosive initiator,thus to protect the latter. An effective design can be defined as that the weak-link fails before the failure of the strong-link,and the system is safe; while an unsuccessful design means that the weak-link fails after the failure of the strong-link,and the system loses in safety. The probability of safety failure exists due to the uncertain failure temperatures of the weak-link and strong-link. In order to obtain the probability of safety failure,a statistical method was used to deal with the uncertainty of the failure temperatures. The integral method and stochastic simulation method were used in calculations. Finally,a sample was given to verify the consistence of the results given by two methods.展开更多
[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according t...[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according to the gender of male and female;the drug administration group was given different doses of Tongchui Baihua capsules,and the drug was administered by continuous gavage for 13 weeks;the general conditions,haematological indexes,blood biochemical indexes and visceral coefficients of the rats were detected at the 13th week and 4 weeks after the drug withdrawal respectively,and the toxic symptoms were observed.[Results]The rats were given Tongchui Baihua capsule in different doses by gavage for 13 weeks,and no obvious toxicity was observed in weight,haematological indexes,blood biochemical indexes and histopathology.[Conclusions]Under the condition of long-term toxicity experiment,Tongchui Baihua capsule was safe for rats.展开更多
Recent years have witnessed rapid advances in the toxicologic assessment of biotechproducts.Safety assessment of a biotech product is a complex and multiple process.This includes a knowledge of its pharmaco-biological...Recent years have witnessed rapid advances in the toxicologic assessment of biotechproducts.Safety assessment of a biotech product is a complex and multiple process.This includes a knowledge of its pharmaco-biological characteristics,and identifyingthe target patient population and the proposed clinical application. To make a decision on the safe human application(the products are administering tohumans for therapeutic purposes),besides the identity and purity of the final product,展开更多
By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 m...By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 mg/kg.By calculating the Maximum Theoretical Safety Limit,according to guidance of Scientific Committee on Consumer Safety(SCCS)of European Union and Toxicological Review of Thallium and Compounds 2009 of United States Environmental Protection Agency(EPA)to assess the risk of cosmetic products.As a result,if the mean concentration of thallium in different kind of cosmetic products does not exceed 0.031 mg/kg,the products will not show significant toxicological risk for consumers.展开更多
To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sifica...To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sification indexes were extracted using driving data from commercial vehicles and four primary and ten secondary safety evaluation indicators.Based on the stability of commercial vehicles transporting goods,the acceleration index is divided into three levels according to the statistical third quartile,and the evaluation expression of the safety index evaluation is established.Drivers were divided into conservative,moderate,and radical using K-means++.The weights corresponding to each index were calculated using a combination of the analytic hierarchy process(AHP)and criteria importance through intercriteria correlation(CRITIC),and the driving behavior scores of various drivers were calculated according to the safety index score standard.The established AHP-CRITIC safety evaluation model was verified using the actual driving behavior data of commercial vehicle drivers.The calculation results show that the proposed evaluation model can clearly distinguish between the types of drivers with different driving styles,verifying its rationality and validity.The evaluation results can provide a reference for transportation management departments and enterprises.展开更多
Metros are critical infrastructure in big cities and evaluation of their safe operation is of increasing im-portance.To make a reasonable safety evaluation for the metro during operation,this paper establishes a ratio...Metros are critical infrastructure in big cities and evaluation of their safe operation is of increasing im-portance.To make a reasonable safety evaluation for the metro during operation,this paper establishes a rational safety evaluation model based on long-term monitoring data of Shanghai Metro Line 2.Four evaluation indicators,ie.,absolute settlement,relative curvature,deformation rate and curvature radius,are adopted.Analytic hierar-chy process(AHP)and entropy method are combined to determine the weights of the indicators.The risk level values at different mileage are calculated and five danger levels are defined accordingly to determine the safety state of Shanghai Metro Line 2,ie.,safe,relatively safe,critical,relatively dangerous,and dangerous.Safety evaluation of Shanghai Metro Line 2 shows that:83.81%areas of Shanghai Metro Line 2 are in safe,relatively safe and critical states,while 15.63%and 0.57%areas are in relatively dangerous and dangerous states,respectively;the parts of Shanghai Metro Line 2 where the risk level values exceed the critical value are mainly distributed around the mileage at 6.0-7.5km and 8.5-11.0 km,and the risk level value peaks around the mileage at 7.3km,to which much attention should be attached and relevant protective measures be taken;the sections with the high risk level values coincide with the distinctly deforming arcas of the metro,indicating that this evaluation method is valid.展开更多
Purpose–It would take billions of miles’field road testing to demonstrate that the safety of automated vehicle is statistically significantly higher than the safety of human driving because that the accident of vehi...Purpose–It would take billions of miles’field road testing to demonstrate that the safety of automated vehicle is statistically significantly higher than the safety of human driving because that the accident of vehicle is rare event.Design/methodology/approach–This paper proposes an accelerated testing method for automated vehicles safety evaluation based on improved importance sampling(IS)techniques.Taking the typical cut-in scenario as example,the proposed method extracts the critical variables of the scenario.Then,the distributions of critical variables are statistically fitted.The genetic algorithm is used to calculate the optimal IS parameters by solving an optimization problem.Considering the error of distribution fitting,the result is modified so that it can accurately reveal the safety benefits of automated vehicles in the real world.Findings–Based on the naturalistic driving data in Shanghai,the proposed method is validated by simulation.The result shows that compared with the existing methods,the proposed method improves the test efficiency by 35 per cent,and the accuracy of accelerated test result is increased by 23 per cent.Originality/value–This paper has three contributions.First,the genetic algorithm is used to calculate IS parameters,which improves the efficiency of test.Second,the result of test is modified by the error correction parameter,which improves the accuracy of test result.Third,typical high-risk cut-in scenarios in China are analyzed,and the proposed method is validated by simulation.展开更多
基金the financial support of the National Natural Science Foundation of China[32201960,32073020]Science and Technology Innovation Program of Hunan Province[2022RC1150]+2 种基金Changsha Municipal Natural Science Foundation[kq2202332]Hunan innovative province construction project[2019NK2041]Agricultural Science and Technology Innovation Project of Hunan Province[2021CX05].
文摘The microbial potential of Penicillium has received critical attention.The present research aimed to elucidate the efficacy of crude enzyme secreted from Penicillium oxalicum WX-209 in degrading citrus segments and evaluate the safety of the process.Results showed that citrus segment membranes gradually dissolved after treatment with the crude enzyme solution,indicating good degradation capability.No significant differences in body weight,food ingestion rate,hematology,blood biochemistry,and weight changes of different organs were found between the enzyme intake and control groups.Serial experiments showed that the crude enzyme had high biological safety.Moreover,the whole genome of P.oxalicum WX-209 was sequenced by PacBio and Illumina platforms.Twenty-five scaffolds were assembled to generate 36 Mbp size of genome sequence comprising 11369 predicted genes modeled with a GC content of 48.33%.A total of 592 genes were annotated to encode enzymes related to carbohydrates,and some degradation enzyme genes were identified in strain P.oxalicum WX-209.
基金Supported by Scientific Research Project of Guangxi Zhuang Autonomous Region Food and Drug Administration(2021 Guangxi Drug Safety Scientific Research Project)"Safety Evaluation of Zhuang Medicine Xiaoyan Zhiyang Formula for the Treatment of Acute Eczema and Contact Dermatitis and Other Skin Diseases"State Administration of Traditional Chinese Medicine High-level Key Discipline Construction Project of Traditional Chinese Medicine-Ethnic Minority Pharmacy(Zhuang Pharmacy)(zyyzdxk-2023165)+2 种基金Guangxi Traditional Chinese Medicine Multidisciplinary Innovation Team Project(GZKJ2309)Funding Project of High-level Talent Cultivation and Innovation Team of Guangxi University of Traditional Chinese Medicine(2022A008)Key R&D Projects of Guangxi Science and Technology Department(Gui Ke AB21196057).
文摘[Objectives]To observe the clinical efficacy and safety of Zhuang Medicine Xiaoyan Zhiyang Formula by retrospective analysis of clinical use.[Methods]A total of 225 cases were collected,including 117 males and 108 females,115 cases of contact dermatitis and 110 cases of acute eczema.Zhuang Medicine Xiaoyan Zhiyang Formula was administered to 225 patients with contact dermatitis and acute eczema and the clinical efficacy was evaluated.[Results]After one week of treatment,among 225 patients with contact dermatitis and acute eczema,76 cases were cured(33.78%),133 cases showed marked response(59.11%),16 cases(7.11%)were improved,0 case was ineffective,and the overall response rate was 92.89%.After one week of Zhuang Medicine Xiaoyan Zhiyang Formula treatment,the symptoms of itching,pain and swelling were significantly improved in all patients,and the rash was partially crusted without new symptom,and there were no complications and adverse reactions.[Conclusions]Zhuang Medicine Xiaoyan Zhiyang Formula therapy has a remarkable effect in the treatment of contact dermatitis and acute eczema.
基金supported by the General Project of Hubei Health Committee of China,No.WJ2019M263(to GW)。
文摘Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of human umbilical cord mesenchymal stem cells(hu MSCs) before clinical application. In this study, hu MSCs were harvested from human amniotic membrane and umbilical cord vascular tissue. A rat model of TBI was established using the controlled cortical impact method. Starting from the third day after injury, the rats were injected with 10 μL of 5 × 10^(6)/m L hu MSCs by cerebral stereotaxis or with 500 μL of 1 × 10^(6)/m L hu MSCs via the tail vein for 3 successive days. hu MSC transplantation decreased the serum levels of proinflammatory cytokines in rats with TBI and increased the serum levels of anti-inflammatory cytokines, thereby exhibiting good immunoregulatory function. The transplanted hu MSCs were distributed in the liver, lung and brain injury sites. No abnormal proliferation or tumorigenesis was found in these organs up to 12 months after transplantation. The transplanted hu MSCs negligibly proliferated in vivo, and apoptosis was gradually observed at later stages. These findings suggest that hu MSC transplantation for the treatment of traumatic brain injury displays good safety. In addition, hu MSCs exhibit good immunoregulatory function, which can help prevent and reduce secondary brain injury caused by the rapid release of inflammatory factors after TBI. This study was approved by the Ethics Committee of Wuhan General Hospital of PLA(approval No. 20160054) on November 1, 2016.
基金supported by the National Natural Science Foundation of China (Grant No. U1334206 and No. 51475388)Science & Technology Development Project of China Railway Corporation (Grant No. J012-C)
文摘The wheel-rail force measurement is of great importance to the condition monitoring and safety evaluation of railway vehicles. In this paper, an improved indirect method for wheel-rail force measurement is proposed to evaluate the running safety of railway vehicles. In this method, the equilibrium equations of a suspended wheelset are derived and the wheel-rail forces are then be obtained from measured suspension and inertia forces. This indirect method avoids structural modifications to the wheelset and is applicable to the long-term operation of railway vehicles. As the wheel-rail lateral forces at two sides of the wheelset are difficult to separate, a new derailment criterion by combined use of wheelset derailment coefficient and wheel unloading ratio is proposed. To illustrate its effectiveness, the indirect method is applied to safety evaluation of rail- way vehicles in different scenarios, such as the cross wind safety of a high-speed train and the safety of a metro vehicle with hunting motions. Then, the feasibility of using this method to identify wheel-rail forces for low-floor light rail vehicles with resilient wheels is discussed. The values identified by this method is compared with that by Simpack simulation for the same low-floor vehicle, which shows a good coincidence between them in the time domain of the wheelset lateral force and the wheel-rail vertical force. In addition, use of the method to determine the high-frequency wheel-rail interaction forces reveals that it is possible to identify the high-frequency wheel-rail forces through the accelerations on the axle box.
基金Major Research Plan of the National Natural Science Foundation of China under Grant No.91315301-10Project of Earthquake Code Compilation and Revising:Postearthquake Field Works-Part 2:Safety Assessment of Buildings under Grant No.14410024701Basic Scientific Research Special Project of IEM,CEA under Grant No.2009A01
文摘This paper describes a set of on-site earthquake safety evaluation systems for buildings, which were developed based on a network platform. The system embedded into the quantitative research results which were completed in accordance with the provisions from Post-earthquake Field Works, Part 2: Safety Assessment of Buildings, GB18208.2 -2001, and was further developed into an easy-to-use software platform. The system is aimed at allowing engineering professionals, civil engineeing technicists or earthquake-affected victims on site to assess damaged buildings through a network after earthquakes. The authors studied the function structure, process design of the safety evaluation module, and hierarchical analysis algorithm module of the system in depth, and developed the general architecture design, development technology and database design of the system. Technologies such as hierarchical architecture design and Java EE were used in the system development, and MySQL5 was adopted in the database development. The result is a complete evaluation process of information collection, safety evaluation, and output of damage and safety degrees, as well as query and statistical analysis of identified buildings. The system can play a positive role in sharing expert post-earthquake experience and promoting safety evaluation of buildings on a seismic field.
基金supported by the National Natural Science Foundation of China (Grant No. 50539010)
文摘A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of a one-machine and three-base system is proposed. The framework of the three-base system has been designed and the structural framework constructed in turn. A practical example is given to illustrate the process of using this system and it can be used for comparison and analysis purposes. The key technology of the system is its ability to reorganize and improve the expert system's knowledge base by establishing the expert system. This system utilizes the computer technology inference process, making safety evaluation conclusions more reasonable and applicable to the actual situation. The system is not only advanced, but also feasible, reliable, artificially intelligent, and has the capacity to constantly grow.
基金supported by a grant from the National High-Tech R&D Program of China (863 Program, N20080753)
文摘The objective of the present study was to evaluate potential adverse effects of diacylglycerol microemulsion (DAGM) in rats/mice. Acute safety evaluation was carried out by giving intragastrically with 20 mL 25% DAG kg-1 body weight of DAGM or water with two groups of mice. Chronic safety evaluation with 40 male and 40 female Sprague-Dawley rats was carried out by setting a control group and 3 different dose groups (n=10 male+10 female) administered with DAGM with 6.7, 10 and 20 mL kg-1 body weight per day. Relevant parameters of liver and kidney function and biochemistry were determined by standard methods at end point. Acute toxicity study revealed the maximum tolerated dose (MTD) of DAGM was 20 mL kg-1 body weight in mice. No death was observed at the dose of 20 mL kg-1 body weight per day. Chronic safety evaluation did not show significant changes on hematological, histopathologic, clinical, and biochemical tests when administered at levels of 6.7, 10 and 20 mL kg-1 body weight per day to rats for 30 d. No significant body weight changes were observed in different dosages in both male and female rats. Our results suggested that acute and chronic adverse effects were not observed in histology and clinical parameters in both mice and rats. The results suggested that DAGM is safe at the experimental levels.
基金supported by the National Natural Science Foundation of China(Grant No51139001)the Natural Science Foundation of Jiangsu Province(Grant NoBK2009479)+2 种基金the Scientific Research Foundation of the State Human Resource Ministry for Returned Chinese Scholars(Grant No2009003)the Scientific Research Foundation for Doctors in Jiangsu Enterprises(Grant No2011-33)the Jiangsu Provincial Postdoctoral Sustentation Fund(Grant No1101049C)
文摘Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact zones of the Xiaowan ultra-high arch dam. The principles of monitoring layout and design are introduced in detail. Prototype monitoring shows that the increment of the interfacial compressive stress is much larger in the impoundment stage than in the regulating stage. The water pressure and time-effect are two main factors affeeting the interfacial stress. The time-effect is the key factor in the initial impoundment stage, and the water pressure is the key factor after impoundment. The contact properties are significantly improved by grouting. This study shows that there are three typical stages in the joint opening hydrographs, namely the compression stage, opening stage, and stable stage. There is a nonlinear relationship between the joint opening and temperature, which can be well described by the S-function. In conclusion, the reinforcement effect is satisfying, and the abutment is safe.
文摘Seismic safety evaluation is a basic work for determining the seismic resistance requirements of major construc-tion projects. The effect, especially the economic effect of the seismic safety evaluation has been generally con-cerned. The paper gives a model for estimating the effect of seismic safety evaluation and calculates roughly the economic effect of seismic safety evaluation with some examples.
文摘A subacute toxicity study of a potent tetanus toxoid (250 Lf) was carried out in guinea pigs.The toxoid was injected subcutaneously at the nape of the neck at dose levels of 1.0, 1.5.and 2.0 ml in Groups Ⅱ. Ⅲ. and Ⅳ, respectively.In the controls (Group Ⅰ) 2.0 ml of aluminum phosphate suspension was given in each injection.Periodic evaluations of body weight, food/water intake, general observable behavior, hematology.and blood chemistry in toxoid-injected guinea pigs were similar to those in control guinea pigs.Thus, the toxoid did not cause any side effects up to four times the dose proposed for humans.1990 Academic Press, Inc.
基金supported by the National Basic Research Program of China(2012CB719703)University of Anhui Provincial Natural Science Fund Project(J2013A068)
文摘Mechanical characterization of steel frame structure after fire are ana- lyzed based on fire dynamics, heat transfer theory, structural mechanics, and finite element theory. We study the temperature characteristics and mechanical prop- erties of steel flame structure under different fire locations and propose a safety evaluation method. We also analyze damage level of main flame components, maximum temperature of fire, thermal characteristics of flame components, fir- ing duration, etc. to provide useful information for fire resistance design of the steel frame structure and post-disaster safety evaluation.
文摘Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strictly regulated. Considering their popular use and increasing safety concerns, thorough evaluations of their efficacy and safety are warranted to protect consumers from potential adverse effects. Toxicity tests (acute, sub- acute and chronic) using animals are widely applied to evaulate adverse effects of a drug and thereby determine its "No Observed Adverse Effect Level" (NOAEL).
文摘Eight trials, with 439 human volunteers who consumed irradiated foods including rice, potatoes, mushrooms, peanuts, and Chinese sausages, as well as diets composed of multiple irradiated foods (irradiated at dosages of 0.2 to 8 kGy) that accounted for 60-66% of the entire diet, were carried out for 2-3 months according to a unified protocol. No adverse effects on body weight, blood pressure, ECG, hematology, blood enzyme activities, serum lipids, or blood or urine 17-hydroxycortisol contents and no chromosomal aberration of peripheral blood lymphocytes were found. It is especially worthwhile to note that there was no change in the polyploidy after consumption of irradiated diets. On the basis of these results and a comprehensive analysis of the physical and chemical characteristics of irradiated foods, temporary hygienic standards for irradiated rice, potatoes, onions, garlic, Chinese sausages, peanuts, and mushrooms were promulgated by the Chinese Ministry of Public Health. 1989 Academic Press, Inc.
基金Sponsored by Science and technology development fund of China academy of engineering physics( 2011A0203010)
文摘In an abnormal high-temperature fire environment,a structure with mechanical-thermal weak-link can be used to predict the permanent failure before the failure of some strong-links,such as explosive initiator,thus to protect the latter. An effective design can be defined as that the weak-link fails before the failure of the strong-link,and the system is safe; while an unsuccessful design means that the weak-link fails after the failure of the strong-link,and the system loses in safety. The probability of safety failure exists due to the uncertain failure temperatures of the weak-link and strong-link. In order to obtain the probability of safety failure,a statistical method was used to deal with the uncertainty of the failure temperatures. The integral method and stochastic simulation method were used in calculations. Finally,a sample was given to verify the consistence of the results given by two methods.
文摘[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according to the gender of male and female;the drug administration group was given different doses of Tongchui Baihua capsules,and the drug was administered by continuous gavage for 13 weeks;the general conditions,haematological indexes,blood biochemical indexes and visceral coefficients of the rats were detected at the 13th week and 4 weeks after the drug withdrawal respectively,and the toxic symptoms were observed.[Results]The rats were given Tongchui Baihua capsule in different doses by gavage for 13 weeks,and no obvious toxicity was observed in weight,haematological indexes,blood biochemical indexes and histopathology.[Conclusions]Under the condition of long-term toxicity experiment,Tongchui Baihua capsule was safe for rats.
文摘Recent years have witnessed rapid advances in the toxicologic assessment of biotechproducts.Safety assessment of a biotech product is a complex and multiple process.This includes a knowledge of its pharmaco-biological characteristics,and identifyingthe target patient population and the proposed clinical application. To make a decision on the safe human application(the products are administering tohumans for therapeutic purposes),besides the identity and purity of the final product,
文摘By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 mg/kg.By calculating the Maximum Theoretical Safety Limit,according to guidance of Scientific Committee on Consumer Safety(SCCS)of European Union and Toxicological Review of Thallium and Compounds 2009 of United States Environmental Protection Agency(EPA)to assess the risk of cosmetic products.As a result,if the mean concentration of thallium in different kind of cosmetic products does not exceed 0.031 mg/kg,the products will not show significant toxicological risk for consumers.
基金the Natural Science Foundation of Guangxi(No.2020GXNSFDA238011)the Open Fund Project of Guangxi Key Laboratory of Automation Detection Technology and Instrument(No.YQ21203)the Independent Research Project of Guangxi Key Laboratory of Auto Parts and Vehicle Technology(No.2020GKLACVTZZ02)。
文摘To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sification indexes were extracted using driving data from commercial vehicles and four primary and ten secondary safety evaluation indicators.Based on the stability of commercial vehicles transporting goods,the acceleration index is divided into three levels according to the statistical third quartile,and the evaluation expression of the safety index evaluation is established.Drivers were divided into conservative,moderate,and radical using K-means++.The weights corresponding to each index were calculated using a combination of the analytic hierarchy process(AHP)and criteria importance through intercriteria correlation(CRITIC),and the driving behavior scores of various drivers were calculated according to the safety index score standard.The established AHP-CRITIC safety evaluation model was verified using the actual driving behavior data of commercial vehicle drivers.The calculation results show that the proposed evaluation model can clearly distinguish between the types of drivers with different driving styles,verifying its rationality and validity.The evaluation results can provide a reference for transportation management departments and enterprises.
基金the National Natural Science Founda-tion of China(Nos.41602283 and 41977216)the Science and Technology Rising-Star Program of Shang-hai(No.19QC1400800)。
文摘Metros are critical infrastructure in big cities and evaluation of their safe operation is of increasing im-portance.To make a reasonable safety evaluation for the metro during operation,this paper establishes a rational safety evaluation model based on long-term monitoring data of Shanghai Metro Line 2.Four evaluation indicators,ie.,absolute settlement,relative curvature,deformation rate and curvature radius,are adopted.Analytic hierar-chy process(AHP)and entropy method are combined to determine the weights of the indicators.The risk level values at different mileage are calculated and five danger levels are defined accordingly to determine the safety state of Shanghai Metro Line 2,ie.,safe,relatively safe,critical,relatively dangerous,and dangerous.Safety evaluation of Shanghai Metro Line 2 shows that:83.81%areas of Shanghai Metro Line 2 are in safe,relatively safe and critical states,while 15.63%and 0.57%areas are in relatively dangerous and dangerous states,respectively;the parts of Shanghai Metro Line 2 where the risk level values exceed the critical value are mainly distributed around the mileage at 6.0-7.5km and 8.5-11.0 km,and the risk level value peaks around the mileage at 7.3km,to which much attention should be attached and relevant protective measures be taken;the sections with the high risk level values coincide with the distinctly deforming arcas of the metro,indicating that this evaluation method is valid.
基金The authors would like to thank the Natural Science Foundation of China(U1764261,51422812)the Shanghai Science and technology project of international cooperation(16510711400)for supporting this research.
文摘Purpose–It would take billions of miles’field road testing to demonstrate that the safety of automated vehicle is statistically significantly higher than the safety of human driving because that the accident of vehicle is rare event.Design/methodology/approach–This paper proposes an accelerated testing method for automated vehicles safety evaluation based on improved importance sampling(IS)techniques.Taking the typical cut-in scenario as example,the proposed method extracts the critical variables of the scenario.Then,the distributions of critical variables are statistically fitted.The genetic algorithm is used to calculate the optimal IS parameters by solving an optimization problem.Considering the error of distribution fitting,the result is modified so that it can accurately reveal the safety benefits of automated vehicles in the real world.Findings–Based on the naturalistic driving data in Shanghai,the proposed method is validated by simulation.The result shows that compared with the existing methods,the proposed method improves the test efficiency by 35 per cent,and the accuracy of accelerated test result is increased by 23 per cent.Originality/value–This paper has three contributions.First,the genetic algorithm is used to calculate IS parameters,which improves the efficiency of test.Second,the result of test is modified by the error correction parameter,which improves the accuracy of test result.Third,typical high-risk cut-in scenarios in China are analyzed,and the proposed method is validated by simulation.