[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components（poliumoside and forsythoside B...[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components（poliumoside and forsythoside B） in the plant and to compare the contents of these components in the medicinal materials from different habitats.[Methods] Comparison and analysis of the contents of the two target components in different parts（root,branch,leaf and fruit） of Callicarpa kwangtungensis from the same habitat and in Callicarpa kwangtungensis from different production areas were performed according to the pharmacopoeia standard.[Result]The highest content of poliumoside wasdetected in fruit,and the content of forsythoside B was the highest in the branch.The contents of the two kinds of components were in order of branch fruit leafroot;The contents of the components were four times higher than China pharmacopeia（0.5%） in Jian,Tonggu,Anyuan,and Ganzhou of Jiangxi Province and the fifth area,Taijiang County of Qiandongnan Miao and Dong Autonomous Prefecture（QMDAP）,among which Ganzhou and Taijiang showed the highest contents.[Conclusion] The differences of poliumoside and forsythoside B were obvious in different habitats and different parts of Callicarpa kwangtungensis.展开更多
As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri（Chai-Hu） is commonly used for the treatment of influenza,which is derived from the dried root...As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri（Chai-Hu） is commonly used for the treatment of influenza,which is derived from the dried roots of Bupleurum chinense DC.and Bupleurum scorzonerifolium Willd.Among of diverse chemical components,saikosaponins are the key active components of the herb medicine.In the present study,we established a method of high performance liquid chromatography（HPLC） coupled with evaporative light scattering detection（ELSD） for simultaneous determination of saikosaponin a,c and d in root,stem,leaf and flower of Bupleurum chinense（B chinense） collected from different areas of Shanxi Province,China.The results from 16 samples of root,stem,leaf and flower of B chinense demonstrated that the total contents of the three saikosaponins in the root of B chinense collected from Dongshan Taiyuan,Xishan,Tianlongshan and Pangquangou were 4.26 mg/g,3.22 mg/g,4.23 mg/g and 3.05 mg/g,respectively.However,there was scarcely any saikosaponins in the stem,leaf and flower of B chinense collected from above-mentioned areas.The method of HPLC coupled with ELSD was suitable for quality control of Radix Bupleuri.The result also confirmed that the root of B chinense was the best medicinal part.展开更多
[Objectives] To analyze the volatile components in different parts of Polygala japonica Houtt. and compare the differences of these volatile components. [Methods] The volatile components in different parts of P. japon...[Objectives] To analyze the volatile components in different parts of Polygala japonica Houtt. and compare the differences of these volatile components. [Methods] The volatile components in different parts of P. japonica Houtt. were analyzed by the headspace solid-phase microextraction( HS-SPME) combined with GC-MS,and the relative percentage of each component was determined by peak area normalization. [Results] Thirty kinds of volatile components were identified from the leaves and rhizomes of P. japonica Houtt.,mainly including olefins,aromatic hydrocarbons,alkanes and esters. [Conclusions] The volatile components in different parts of P. japonica Houtt. were different,and there may be difference in the medicinal value of volatile components in different parts,thus it is required to take an overall consideration of these differences in the development and utilization of P. japonica Houtt.展开更多
BACKGROUND： Previous researches found that animal models with Parkinson disease （PD） could be established by injecting 6-hydroxydopamine （6-OHDA） into medial forebrain bundle （MFB）, substantia nigra compacta （...BACKGROUND： Previous researches found that animal models with Parkinson disease （PD） could be established by injecting 6-hydroxydopamine （6-OHDA） into medial forebrain bundle （MFB）, substantia nigra compacta （SNC） and caudate-putamen complex （CPU） of the nigrostriatal pathway. OBJECTIVE ： To compare behavioral, biochemica 6-OHDA injections in the areas of MFB, SNC and DESIGN： Controlled observational study and histological properties of these rats undergoing the CPU respectively. SEI-IING： Department of Neurology, First Affiliated Hospital of Guangxi Medical University MATERIALS： A total of 64 adult female SD rats weighing 180-230 g were provided by the Animal Experimental Center of Guangxi Medical University. 6-OHDA （Sigma Company, USA）; Brain solid positioner （Standard model 51600, Stoelting Co., IL, USA）; rotational monitoring of little animal （type QL-1, USA）; high liquid chromatography （HLC, Waters Company）. METHOOS： The experiment was carried out in the Medical Experimental Center of Guangxi Medical University from February to December 2005. ① According to digital table, 64 SD rats were divided into MFB group, SNC group, CPU group and control group with 16 in each group. On the basis of the brain atlas of Paxinos, rats in the first three groups were injected with 5 μL 6-OHDA into right MFB （0 mm of line of incisor tooth, A/P 4.4 mm, L/R 1.2 mm, ON -7.8 mm）, SNC （line of incisor tooth just equal to horizon, A/P -4.8 mm, L/R 1.6 mm, ON -7.8 mm） and CPU （0 mm of line of incisor tooth, A/P 1.2 mm, L/R 2.7 mm, ON -5.4 mm）, respectively. The rats in control group were injected with 5 μL ascorbic acid solution （2 g/L）. One week after operation, 0.1 g/L apomorphine （Apo, 0.05 mg/kg） was subcutaneously injected into neck and then rotational behavior induced by Apo was recorded once a week for 8 weeks. The PD models were considered successful only when rotational times more than or equal to 7 times per minute. Eight weeks after operation, micro-perfusion was used to obtain micro-perfusate in bilateral CPU and contents of 3,4-dihydroxyphenylacetic acid （3,4-DOPAC） and homovanillic acid （HVA） were also measured. In addition, amount of tyrosine hydroxylase positive cells （TH＊） in SNC was counted with immuno- histochemical staining. MAIN OUTCOME MEASURES ： ① Successful rate of PD models; ② contents of dopamine and its metabolite in MFB, SNC and CPU groups and TH＊ amount. RESULTS： All 64 SD rats were involved in the final analysis. ③ Successful rate and rotational behavior： One week after operation, there were 6 successful models both in SNC and MFB groups; in the 2^nd week, there were 6 both in SNC and MFB groups and 1 in CPU group; in the 3^nd week, there were 1 in MFB group and 3 in CPU group; in the 4^nd week, there were 3 in CPU group. Otherwise, no successful case was found out in the next 3 weeks. Abnormal rotational behavior was not observed in control group. Four weeks after operation, successful rates were 81% （13/16） in MFB group, 75% （12/16） in SNC group and 44% （7/16） in CPU group.② Contents of 3, 4-DOPAC and HVA： Eight weeks after operation, contents in the SNC area of the injured side were lower than those on non-lesion side （P 〈 0.01）.③Changes of TH＋ amount： Eight weeks after operation, TH＋ amount in the SNC area of the lesion side was lower than that on non-lesion side （P 〈 0.01 ）. CONCLUSION： Injecting 6-OHDA into MFB, SNC and CPU can damage dopaminergic cells and establish successful PD models.展开更多
[Objectives] This study was conducted to analyze the composition of volatile oil in different parts of fennel(Foenicuzu vulgare Mill.) and to compare the differences in the composition of volatile oil in different par...[Objectives] This study was conducted to analyze the composition of volatile oil in different parts of fennel(Foenicuzu vulgare Mill.) and to compare the differences in the composition of volatile oil in different parts of fennel.[Methods]The steam distillation method was applied to extract volatile oil from different parts of fennel,and the components of volatile oil from different parts of fennel were separated and identified by GC-MS.The relative content of each component was determined by the peak area normalization method.[Results]37,33,18,and 44 chemical components were separated from the volatile oil of fennel roots,stems,young leaves and fruit,respectively,accounting for 98.64%,99.34%,99.59% and 95.99% of the total volatile oil of corresponding parts.A total of 77 chemical components were identified in the four parts,of which 5 were common components.The main component of the volatile oil in the stems and young leaves was trans-anethole.The main components of the volatile oil in fruit were estragole and trans-anethole.And the main component of the volatile oil in the roots was dill apiol.The components in the volatile oil of fennel roots,stems,young leaves and fruit were different in type and content.[Conclusions]This study provides a theoretical reference for the further effective development and utilization of fennel resources.展开更多
[Objectives] To analyze and compare the difference in volatile components of different cultivars and different parts of Artemisia argyi by using headspace solid phase microextraction( HS-SPME) and provide scientific b...[Objectives] To analyze and compare the difference in volatile components of different cultivars and different parts of Artemisia argyi by using headspace solid phase microextraction( HS-SPME) and provide scientific basis for comprehensive development and rational utilization of Artemisia argyi. [Methods]Firstly,HS-SPME was used to extract the volatile components from the leaves,seeds,and stems of seven-tip Artemisia argyi,five-tip Artemisia argyi,and golden Artemisia argyi. Their chemical composition was analyzed by gas chromatographymass spectrometry( GC-MS),and the relative mass fraction of each component was determined by area normalization method. [Results] For the same variety of Artemisia argyi,the content of volatile components in leaves was higher than in seeds and stems except camphor,and the content of volatile components in seven-tip Artemisia argyi leaves was higher than in five-tip Artemisia argyi and golden Artemisia argyi leaves.HS-SPME-GC-MS analysis showed that eucalyptol,camphor,thujone,α-pinene,1-caryophyllene and caryophyllene oxide with higher content were detected in different parts of the different cultivars of Artemisia argyi. [Conclusions]Seven-tip Artemisia argyi leaves were the best medicinal parts of the three cultivars,followed by seven-tip Artemisia argyi seeds.展开更多
[Objectives]This study aimed to determine the total coumarin content and antioxidant activity in vitro of Obazema,a Yi Medicine.[Methods]The extraction process of coumarin from Obazema was optimized by response surfac...[Objectives]This study aimed to determine the total coumarin content and antioxidant activity in vitro of Obazema,a Yi Medicine.[Methods]The extraction process of coumarin from Obazema was optimized by response surface method,and the total contents of coumarin in different sources and different parts of Obazema were compared.With Vc,chlorogenic acid and citric acid as positive controls,the antioxidant activity of the ethanol extracts of different parts of Obazema was determined.[Results]The optimum extraction process for coumarin from Obazema were as follows:80%ethanol,solid to liquid ratio 1∶67,extraction time 120 min and extraction temperature 57℃.The total contents of coumarin in roots,stems,leaves,flowers and fruit of Boenninghausenia sessilicarpa Levl.and B.albiflora(Hook.)Reichb.were 7.75,6.50,33.45 and 44.35,and 8.1,4.6,17.8 and 18.7 mg/g,respectively.The free radicle-scavenging activity of coumarin from Obazema had certain dose-effect relationship,and was slightly stronger than that of the positive drugs.Under the phenanthroline-Fe ^2+method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>citric acid>chlorogenic acid;under the DPPH method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid;and under the ABSTS+method,the free radicle-scavenging capacity ranked was in the order as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid.[Conclusions]There are significant differences in coumarin content between different sources and different parts of Obazema.When coumarin is used as the main active substance,Obazema is better harvested during the flowering period,and the free radicle-scavenging activity of B.sessilicarpa Levl.is higher than that of B.albiflora(Hook.)Reichb.The antioxidant activity of the flower-fruit ethanol extracts of B.sessilicarpa Levl.and B.albiflora(Hook.)Reichb.is stronger than that of the commonly used antioxidants such as Vc,chlorogenic acid and citric acid,which is related to antioxidant components in the ethanol extracts.展开更多
Objective:This study aims to explore the benefit analysis of the same disease in different departments of public hospitals under the DIP payment method.Methods:This study is a retrospective analysis that selected clin...Objective:This study aims to explore the benefit analysis of the same disease in different departments of public hospitals under the DIP payment method.Methods:This study is a retrospective analysis that selected clinical data from patients who received treatment in the Department of Orthopedics and the Department of Acupuncture and Moxibustion at our hospital from January 1,2023,to December 31,2023.The study compared the costs of medications,examinations,treatments,laboratory tests,nursing and other expenses,and total treatment costs between the two departments.It analyzed the cost structure of the two departments and proposed further improvement suggestions.Results:The study results indicated that the total costs in the Department of Acupuncture and Moxibustion were significantly higher than those in the Department of Orthopedics.Among medication costs,the total medication costs in the Department of Orthopedics were higher than those in the Department of Acupuncture and Moxibustion,with costs for Western medicine,proprietary Chinese medicine,and herbal medicine all being higher(p<0.05).Regarding examination costs,consultation fees in the Department of Orthopedics were lower than those in the Department of Acupuncture and Moxibustion,while examination costs were higher(p<0.05).In terms of treatment costs,orthopedic treatment and surgical fees were higher than those in the Department of Acupuncture and Moxibustion(p<0.05).For laboratory test costs,orthopedic laboratory fees were significantly higher than those in the Department of Acupuncture and Moxibustion(p<0.05).Among nursing and other expenses,orthopedic blood transfusion,bed fees,and other expenses were higher than those in the Department of Acupuncture and Moxibustion,while nursing fees were lower(p<0.05).Conclusion:Treatment fees in the Department of Acupuncture and Moxibustion are the core and account for a relatively high proportion of the total costs.The benefits generated by the Department of Orthopedics are primarily derived from medication,examination,and laboratory fees,aligning with the characteristics of combining diagnosis,medication,and surgical intervention in orthopedic treatment.Consultation fees,nursing fees,and bed fees in the Department of Acupuncture and Moxibustion are higher than those in the Department of Orthopedics,indicating a longer treatment cycle in acupuncture,which warrants clinical attention.展开更多
A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who...A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who are at the initial moment of service period is analyzed by using a total probability theorem,and the stability condition of the system is obtained.The stationary distribution of the queue length is solved by the regeneration cycle method.The stochastic decomposition of queue length in the steady state is calculated,and the service cycle is obtained.Moreover,classified discussions are established in order to solve the steady-state distribution for the waiting time.The variation of system performance indicators with parameters is analyzed by performing numerical experiments.展开更多
SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing...SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing machine under loads of 20 to 50 N against YG6 cemented carbide.The experimental results show that the friction coefficients of all samples increase with increasing load.The 25vol%composite exhibits the lowest friction coefficient(0.1669-0.2716),while the 60vol%composite exhibits the highest(0.3237-0.3990),with the 6092 aluminum alloy falling between the two.The wear volume and specific wear rate also increase with load,but the composites with a higher Si C content demonstrate smaller increments,with the 60vol%composite exhibiting superior wear resistance.Under a 30 N load,the wear scars of the 60vol%composite show a significant increase in the contents of elements such as C,Co,W,and O,indicating more severe wear of the counterpart material.Scanning electron microscopy(SEM)reveals wear mechanisms including adhesive wear,two-body sliding and three-body rolling wear of particles,and delamination.展开更多
Imidazole(IM)particles in the atmosphere affect climate,atmospheric chemical reactions,and human health.However,research on IM particles in the Sichuan Basin(SCB),one of the areas of China affected most heavily by haz...Imidazole(IM)particles in the atmosphere affect climate,atmospheric chemical reactions,and human health.However,research on IM particles in the Sichuan Basin(SCB),one of the areas of China affected most heavily by haze,remains very scarce.This study used single-particle aerosol mass spectrometry to investigate IM-containing particles in Chengdu,one of the megacities in the SCB,during summer and winter before and after implemen-tation of the Three-year Action Plan to Win the Blue-Sky Defense War(BSDW).We found that IM-containing particles accounted for 1.2%–12.0%of all detected particles,and they highly mixed with carbonaceous com-ponents,secondary inorganic species,and organic nitrogen.From before to after the BSDW,the proportion of IM-containing particles decreased by 1.8%in summer,but increased by 9.6%in winter.Ammonium/amines and carbonyl compounds were closely related to IM-containing particles;the highest proportion of IM-containing particles occurred in particles mixed with amines and carbonyls.The number fraction of IM-containing particles in all seasons was higher at night than during daytime.The potential source areas of IM-containing particles showed notable narrowing after the BSDW,and the high-value areas were found distributed closer to Chengdu and its surrounding areas.In the winter before the BSDW,most IM-containing particles(>70%)were mixed with organic carbon(OC)particles,and the contributions of OC and mixed organic–elemental carbon(OC-EC)particles increased with aggravation of pollution,whereas OC-EC and Metal particles played a more crucial role in the winter after the BSDW.展开更多
Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and...Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and gridded data)and actual climate data(fixed-point observations near the sampling sites),in northeastern China’s warm temperate zone and analyzed differences in their correlations with tree-ring width index.The results were:(1)Gridded temperature data,as well as precipitation and relative humidity data from the Huailai meteorological station,was more consistent with the actual climate data;in contrast,gridded soil moisture content data showed significant discrepancies.(2)Horizontal distance had a greater impact on the representativeness of actual climate conditions than vertical elevation differences.(3)Differences in consistency between alternative and actual climate data also affected their correlations with tree-ring width indices.In some growing season months,correlation coefficients,both in magnitude and sign,differed significantly from those based on actual data.The selection of different alternative climate datasets can lead to biased results in assessing forest responses to climate change,which is detrimental to the management of forest ecosystems in harsh environments.Therefore,the scientific and rational selection of alternative climate data is essential for dendroecological and climatological research.展开更多
This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△...This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2.展开更多
Cistanche deserticola(CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein,~1H NMR spectroscopy was employed to characterize the chemical profile and to distingui...Cistanche deserticola(CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein,~1H NMR spectroscopy was employed to characterize the chemical profile and to distinguish the different parts, as well as to propose a new processing workflow for CD.Signal assignment was achieved by multiple one and two dimensional NMR spectroscopic techniques in combination with available databases and authentic compounds. The upper parts of the plant were distinguished from the lower parts by combining ~1H NMR spectroscopic dataset with multivariate statistical analysis. A new processing method that hyphenated steaming with freeze-drying, was demonstrated to be superior to either steaming coupled with oven-drying or direct freeze-drying via holistic ~1H NMR-based metabolomic characterization. Phenylethanoid glycosides, mainly echinacoside and acteoside, were screened out and confirmed as the chemical markers responsible for exhibiting the superiority of the new processing workflow, whereas serial primary metabolites, especially carbohydrates and tricarboxylic acid cycle metabolites, were found as the primary molecules governing the discrimination between the upper and lower parts of the plant. Collectively,~1H NMR spectroscopy was demonstrated as a versatile analytical tool to characterize the chemical profile and to guide the indepth exploitation of CD by providing comprehensive qualitative and quantitative information.展开更多
A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx...A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx 4).展开更多
Velvet antler is an important and precious traditional Chinese animal medicine,and was used for strengthening the kidney,anti-fatigue,improving sexual function and so on.But the evaluation methods of velvet antler and...Velvet antler is an important and precious traditional Chinese animal medicine,and was used for strengthening the kidney,anti-fatigue,improving sexual function and so on.But the evaluation methods of velvet antler and the scientific evidence for the use of antler is insufficient.Materials and Vacuum freeze drier was used for dehydration of the fresh antler at-60.,6 pa for 24 h.展开更多
The formation and development of weather events has a great impact on the diffusion, accumulation and transport of air pollutants, and causes great changes in the particulate pollution level. It is very important to s...The formation and development of weather events has a great impact on the diffusion, accumulation and transport of air pollutants, and causes great changes in the particulate pollution level. It is very important to study their influence on particulate pollution. Lanzhou is one of the most particulate-polluted cities in China and even in the world. Particulate matter （PM） including TSP, PM〉10, PMzs-10, PM2.5 and PM1.0 concentrations were simultaneously measured during 2005-2007 in Lanzhou to evaluate the influence of three kinds of weather events - dost, precipitation and cold front - on the concentrations of PM with different sizes and detect the temporal evolution. The main results are as follows： （1） the PM pollution in Lanzhou during dust events was very heavy and the rate of increase in the concentration of PM2.5-10 was the highest of the five kinds of particles. During dust-storm events, the highest peaks of the concentrations of fine particles （PM2.5 and PM1.0） occurred 3 hr later than those of coarse particles （PM〉10 and PM/.5-10）. （2） The major effect of precipitation events on PM is wet scavenging. The scavenging rates of particles were closely associated with the kinds of precipitation events. The scavenging rates of TSP, PM〉10 and PMa.5-10 by convective precipitation were several times as high as those caused by frontal precipitation for the same precipitation amount, the reason being the different formation mechanism and precipitation characteristics of the two kinds of precipitation. Moreover, there exists a limiting value for the scavenging rates of particles by precipitation. （3） The major effect of cold-front events on particles is clearance. However, during cold-front passages, the PM concentrations could sometimes rise first and decrease afterwards, which is the critical difference in the influence of cold fronts on the concentrations of particulate pollutants vs. gaseous pollutants.展开更多
Background： Among numerous health benefits, sports participation has been shown to reduce the risk of overweight and obesity in children and adolescents. Schools represent an ideal environment for increasing sports p...Background： Among numerous health benefits, sports participation has been shown to reduce the risk of overweight and obesity in children and adolescents. Schools represent an ideal environment for increasing sports participation, but it is unclear how access and choice influence participation and whether characteristics of the school sports program differentially influence boys＇ and girls＇ participation. The purpose of this study was to evaluate the characteristics of high school athletic programs and determine the extent to which these characteristics influenced boys＇ and girls＇ sports team participation. Methods： Longitudinal telephone surveys were conducted with 1244 New Hampshire and Vermont students. Students self-reported their sports team participation at baseline （elementary school） and follow-up （high school）. High school personnel were surveyed to assess sports oppor- tunities, which were defined for this analysis as the number of sports offered per 100 students （i.e., choice） and the percent of sports offered that did not restrict the number of players （i.e., access）. Results： Approximately 70% of children participated on at least one sports team, including 73% of boys and 66% of girls. We detected sta- tistically significant interactions between sex and two school opportunity variables： 1） the number of sports offered per 100 students （i.e., choice） and 2） the percent of sports offered that did not restrict the number of players （i.e., access）. After controlling for children＇s baseline sports participation and other covariates, boys were more likely to play on at least one sports team per year if their school did not restrict participation in the most popular sports （relative risk, RR = 1.12, p 〈 0.01）; in contrast, girls were more likely to play on at least one sports team per year if their school offered a wider variety of sports （RR = 1.47, p 〈 0.001）. Conclusion： Sports participation has previously been shown to confer a number of health benefits; as such, school sports programs may be an important, effective, and underused target for public health efforts, including obesity prevention programs. Efforts to increase physical activity among youth should consider both access and choice in school athletic programs. Schools may need to use different strategies to increase sports participation in boys and girls.展开更多
Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared （NIR） and mid-infrared （MIR） technology combined ...Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared （NIR） and mid-infrared （MIR） technology combined with supervised pattern recognition based on partial least-squares discriminant analysis （PLSDA） was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct （MSC） fingerprint and second derivative （2nd derivative） fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu.展开更多
A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is impro...A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation stages.The remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status information.The late operating trend is predicted by the use of the particle filter algorithm.The rolling bearing full life experimental data validate the proposed method.Further,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability.展开更多
文摘[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components（poliumoside and forsythoside B） in the plant and to compare the contents of these components in the medicinal materials from different habitats.[Methods] Comparison and analysis of the contents of the two target components in different parts（root,branch,leaf and fruit） of Callicarpa kwangtungensis from the same habitat and in Callicarpa kwangtungensis from different production areas were performed according to the pharmacopoeia standard.[Result]The highest content of poliumoside wasdetected in fruit,and the content of forsythoside B was the highest in the branch.The contents of the two kinds of components were in order of branch fruit leafroot;The contents of the components were four times higher than China pharmacopeia（0.5%） in Jian,Tonggu,Anyuan,and Ganzhou of Jiangxi Province and the fifth area,Taijiang County of Qiandongnan Miao and Dong Autonomous Prefecture（QMDAP）,among which Ganzhou and Taijiang showed the highest contents.[Conclusion] The differences of poliumoside and forsythoside B were obvious in different habitats and different parts of Callicarpa kwangtungensis.
基金Shanxi Educational Committee(Grant No.20111113)Shanxi Science and Technology Department(Grant No.2016ZD0201)
文摘As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri（Chai-Hu） is commonly used for the treatment of influenza,which is derived from the dried roots of Bupleurum chinense DC.and Bupleurum scorzonerifolium Willd.Among of diverse chemical components,saikosaponins are the key active components of the herb medicine.In the present study,we established a method of high performance liquid chromatography（HPLC） coupled with evaporative light scattering detection（ELSD） for simultaneous determination of saikosaponin a,c and d in root,stem,leaf and flower of Bupleurum chinense（B chinense） collected from different areas of Shanxi Province,China.The results from 16 samples of root,stem,leaf and flower of B chinense demonstrated that the total contents of the three saikosaponins in the root of B chinense collected from Dongshan Taiyuan,Xishan,Tianlongshan and Pangquangou were 4.26 mg/g,3.22 mg/g,4.23 mg/g and 3.05 mg/g,respectively.However,there was scarcely any saikosaponins in the stem,leaf and flower of B chinense collected from above-mentioned areas.The method of HPLC coupled with ELSD was suitable for quality control of Radix Bupleuri.The result also confirmed that the root of B chinense was the best medicinal part.
文摘[Objectives] To analyze the volatile components in different parts of Polygala japonica Houtt. and compare the differences of these volatile components. [Methods] The volatile components in different parts of P. japonica Houtt. were analyzed by the headspace solid-phase microextraction( HS-SPME) combined with GC-MS,and the relative percentage of each component was determined by peak area normalization. [Results] Thirty kinds of volatile components were identified from the leaves and rhizomes of P. japonica Houtt.,mainly including olefins,aromatic hydrocarbons,alkanes and esters. [Conclusions] The volatile components in different parts of P. japonica Houtt. were different,and there may be difference in the medicinal value of volatile components in different parts,thus it is required to take an overall consideration of these differences in the development and utilization of P. japonica Houtt.
基金Foundation for the Returned Overseas Chinese Scholars of Guangxi Zhuang Autonomous Region, No. 0448017
文摘BACKGROUND： Previous researches found that animal models with Parkinson disease （PD） could be established by injecting 6-hydroxydopamine （6-OHDA） into medial forebrain bundle （MFB）, substantia nigra compacta （SNC） and caudate-putamen complex （CPU） of the nigrostriatal pathway. OBJECTIVE ： To compare behavioral, biochemica 6-OHDA injections in the areas of MFB, SNC and DESIGN： Controlled observational study and histological properties of these rats undergoing the CPU respectively. SEI-IING： Department of Neurology, First Affiliated Hospital of Guangxi Medical University MATERIALS： A total of 64 adult female SD rats weighing 180-230 g were provided by the Animal Experimental Center of Guangxi Medical University. 6-OHDA （Sigma Company, USA）; Brain solid positioner （Standard model 51600, Stoelting Co., IL, USA）; rotational monitoring of little animal （type QL-1, USA）; high liquid chromatography （HLC, Waters Company）. METHOOS： The experiment was carried out in the Medical Experimental Center of Guangxi Medical University from February to December 2005. ① According to digital table, 64 SD rats were divided into MFB group, SNC group, CPU group and control group with 16 in each group. On the basis of the brain atlas of Paxinos, rats in the first three groups were injected with 5 μL 6-OHDA into right MFB （0 mm of line of incisor tooth, A/P 4.4 mm, L/R 1.2 mm, ON -7.8 mm）, SNC （line of incisor tooth just equal to horizon, A/P -4.8 mm, L/R 1.6 mm, ON -7.8 mm） and CPU （0 mm of line of incisor tooth, A/P 1.2 mm, L/R 2.7 mm, ON -5.4 mm）, respectively. The rats in control group were injected with 5 μL ascorbic acid solution （2 g/L）. One week after operation, 0.1 g/L apomorphine （Apo, 0.05 mg/kg） was subcutaneously injected into neck and then rotational behavior induced by Apo was recorded once a week for 8 weeks. The PD models were considered successful only when rotational times more than or equal to 7 times per minute. Eight weeks after operation, micro-perfusion was used to obtain micro-perfusate in bilateral CPU and contents of 3,4-dihydroxyphenylacetic acid （3,4-DOPAC） and homovanillic acid （HVA） were also measured. In addition, amount of tyrosine hydroxylase positive cells （TH＊） in SNC was counted with immuno- histochemical staining. MAIN OUTCOME MEASURES ： ① Successful rate of PD models; ② contents of dopamine and its metabolite in MFB, SNC and CPU groups and TH＊ amount. RESULTS： All 64 SD rats were involved in the final analysis. ③ Successful rate and rotational behavior： One week after operation, there were 6 successful models both in SNC and MFB groups; in the 2^nd week, there were 6 both in SNC and MFB groups and 1 in CPU group; in the 3^nd week, there were 1 in MFB group and 3 in CPU group; in the 4^nd week, there were 3 in CPU group. Otherwise, no successful case was found out in the next 3 weeks. Abnormal rotational behavior was not observed in control group. Four weeks after operation, successful rates were 81% （13/16） in MFB group, 75% （12/16） in SNC group and 44% （7/16） in CPU group.② Contents of 3, 4-DOPAC and HVA： Eight weeks after operation, contents in the SNC area of the injured side were lower than those on non-lesion side （P 〈 0.01）.③Changes of TH＋ amount： Eight weeks after operation, TH＋ amount in the SNC area of the lesion side was lower than that on non-lesion side （P 〈 0.01 ）. CONCLUSION： Injecting 6-OHDA into MFB, SNC and CPU can damage dopaminergic cells and establish successful PD models.
基金Supported by Anshun Science and Technology Innovation Platform Construction Project(ASKP[2017]03)。
文摘[Objectives] This study was conducted to analyze the composition of volatile oil in different parts of fennel(Foenicuzu vulgare Mill.) and to compare the differences in the composition of volatile oil in different parts of fennel.[Methods]The steam distillation method was applied to extract volatile oil from different parts of fennel,and the components of volatile oil from different parts of fennel were separated and identified by GC-MS.The relative content of each component was determined by the peak area normalization method.[Results]37,33,18,and 44 chemical components were separated from the volatile oil of fennel roots,stems,young leaves and fruit,respectively,accounting for 98.64%,99.34%,99.59% and 95.99% of the total volatile oil of corresponding parts.A total of 77 chemical components were identified in the four parts,of which 5 were common components.The main component of the volatile oil in the stems and young leaves was trans-anethole.The main components of the volatile oil in fruit were estragole and trans-anethole.And the main component of the volatile oil in the roots was dill apiol.The components in the volatile oil of fennel roots,stems,young leaves and fruit were different in type and content.[Conclusions]This study provides a theoretical reference for the further effective development and utilization of fennel resources.
基金Supported by Natural Science Foundation of Hubei Province(2004AB242)
文摘[Objectives] To analyze and compare the difference in volatile components of different cultivars and different parts of Artemisia argyi by using headspace solid phase microextraction( HS-SPME) and provide scientific basis for comprehensive development and rational utilization of Artemisia argyi. [Methods]Firstly,HS-SPME was used to extract the volatile components from the leaves,seeds,and stems of seven-tip Artemisia argyi,five-tip Artemisia argyi,and golden Artemisia argyi. Their chemical composition was analyzed by gas chromatographymass spectrometry( GC-MS),and the relative mass fraction of each component was determined by area normalization method. [Results] For the same variety of Artemisia argyi,the content of volatile components in leaves was higher than in seeds and stems except camphor,and the content of volatile components in seven-tip Artemisia argyi leaves was higher than in five-tip Artemisia argyi and golden Artemisia argyi leaves.HS-SPME-GC-MS analysis showed that eucalyptol,camphor,thujone,α-pinene,1-caryophyllene and caryophyllene oxide with higher content were detected in different parts of the different cultivars of Artemisia argyi. [Conclusions]Seven-tip Artemisia argyi leaves were the best medicinal parts of the three cultivars,followed by seven-tip Artemisia argyi seeds.
文摘[Objectives]This study aimed to determine the total coumarin content and antioxidant activity in vitro of Obazema,a Yi Medicine.[Methods]The extraction process of coumarin from Obazema was optimized by response surface method,and the total contents of coumarin in different sources and different parts of Obazema were compared.With Vc,chlorogenic acid and citric acid as positive controls,the antioxidant activity of the ethanol extracts of different parts of Obazema was determined.[Results]The optimum extraction process for coumarin from Obazema were as follows:80%ethanol,solid to liquid ratio 1∶67,extraction time 120 min and extraction temperature 57℃.The total contents of coumarin in roots,stems,leaves,flowers and fruit of Boenninghausenia sessilicarpa Levl.and B.albiflora(Hook.)Reichb.were 7.75,6.50,33.45 and 44.35,and 8.1,4.6,17.8 and 18.7 mg/g,respectively.The free radicle-scavenging activity of coumarin from Obazema had certain dose-effect relationship,and was slightly stronger than that of the positive drugs.Under the phenanthroline-Fe ^2+method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>citric acid>chlorogenic acid;under the DPPH method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid;and under the ABSTS+method,the free radicle-scavenging capacity ranked was in the order as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid.[Conclusions]There are significant differences in coumarin content between different sources and different parts of Obazema.When coumarin is used as the main active substance,Obazema is better harvested during the flowering period,and the free radicle-scavenging activity of B.sessilicarpa Levl.is higher than that of B.albiflora(Hook.)Reichb.The antioxidant activity of the flower-fruit ethanol extracts of B.sessilicarpa Levl.and B.albiflora(Hook.)Reichb.is stronger than that of the commonly used antioxidants such as Vc,chlorogenic acid and citric acid,which is related to antioxidant components in the ethanol extracts.
文摘Objective:This study aims to explore the benefit analysis of the same disease in different departments of public hospitals under the DIP payment method.Methods:This study is a retrospective analysis that selected clinical data from patients who received treatment in the Department of Orthopedics and the Department of Acupuncture and Moxibustion at our hospital from January 1,2023,to December 31,2023.The study compared the costs of medications,examinations,treatments,laboratory tests,nursing and other expenses,and total treatment costs between the two departments.It analyzed the cost structure of the two departments and proposed further improvement suggestions.Results:The study results indicated that the total costs in the Department of Acupuncture and Moxibustion were significantly higher than those in the Department of Orthopedics.Among medication costs,the total medication costs in the Department of Orthopedics were higher than those in the Department of Acupuncture and Moxibustion,with costs for Western medicine,proprietary Chinese medicine,and herbal medicine all being higher(p<0.05).Regarding examination costs,consultation fees in the Department of Orthopedics were lower than those in the Department of Acupuncture and Moxibustion,while examination costs were higher(p<0.05).In terms of treatment costs,orthopedic treatment and surgical fees were higher than those in the Department of Acupuncture and Moxibustion(p<0.05).For laboratory test costs,orthopedic laboratory fees were significantly higher than those in the Department of Acupuncture and Moxibustion(p<0.05).Among nursing and other expenses,orthopedic blood transfusion,bed fees,and other expenses were higher than those in the Department of Acupuncture and Moxibustion,while nursing fees were lower(p<0.05).Conclusion:Treatment fees in the Department of Acupuncture and Moxibustion are the core and account for a relatively high proportion of the total costs.The benefits generated by the Department of Orthopedics are primarily derived from medication,examination,and laboratory fees,aligning with the characteristics of combining diagnosis,medication,and surgical intervention in orthopedic treatment.Consultation fees,nursing fees,and bed fees in the Department of Acupuncture and Moxibustion are higher than those in the Department of Orthopedics,indicating a longer treatment cycle in acupuncture,which warrants clinical attention.
基金supported by the National Natural Science Foundation of China(61973261)the Natural Science Foundation of Jilin Province(20210101151JC).
文摘A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who are at the initial moment of service period is analyzed by using a total probability theorem,and the stability condition of the system is obtained.The stationary distribution of the queue length is solved by the regeneration cycle method.The stochastic decomposition of queue length in the steady state is calculated,and the service cycle is obtained.Moreover,classified discussions are established in order to solve the steady-state distribution for the waiting time.The variation of system performance indicators with parameters is analyzed by performing numerical experiments.
基金Funded by the Provincial Talent Project of Gansu Province(No.2025QNGR18)the Natural Science Foundation of Gansu Province(No.23JRRA1647)+2 种基金the"Qizhi"Talent Cultivation Project of Lanzhou Institute of Technology(No.2025QZ-02)the Education Science and Technology Innovation Project of Gansu Province(No.2025A-229)the Lanzhou Science and Technology Development Guidance Plan Project(No.2024-9-307)。
文摘SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing machine under loads of 20 to 50 N against YG6 cemented carbide.The experimental results show that the friction coefficients of all samples increase with increasing load.The 25vol%composite exhibits the lowest friction coefficient(0.1669-0.2716),while the 60vol%composite exhibits the highest(0.3237-0.3990),with the 6092 aluminum alloy falling between the two.The wear volume and specific wear rate also increase with load,but the composites with a higher Si C content demonstrate smaller increments,with the 60vol%composite exhibiting superior wear resistance.Under a 30 N load,the wear scars of the 60vol%composite show a significant increase in the contents of elements such as C,Co,W,and O,indicating more severe wear of the counterpart material.Scanning electron microscopy(SEM)reveals wear mechanisms including adhesive wear,two-body sliding and three-body rolling wear of particles,and delamination.
基金supported by Sichuan Science and Technology Program(No.2024NSFSC0060)the National Natural Science Foundation of China(No.U23A2030)the Basic Research Cultivation Support Plan of Southwest Jiaotong University(No.2682023ZTPY016).
文摘Imidazole(IM)particles in the atmosphere affect climate,atmospheric chemical reactions,and human health.However,research on IM particles in the Sichuan Basin(SCB),one of the areas of China affected most heavily by haze,remains very scarce.This study used single-particle aerosol mass spectrometry to investigate IM-containing particles in Chengdu,one of the megacities in the SCB,during summer and winter before and after implemen-tation of the Three-year Action Plan to Win the Blue-Sky Defense War(BSDW).We found that IM-containing particles accounted for 1.2%–12.0%of all detected particles,and they highly mixed with carbonaceous com-ponents,secondary inorganic species,and organic nitrogen.From before to after the BSDW,the proportion of IM-containing particles decreased by 1.8%in summer,but increased by 9.6%in winter.Ammonium/amines and carbonyl compounds were closely related to IM-containing particles;the highest proportion of IM-containing particles occurred in particles mixed with amines and carbonyls.The number fraction of IM-containing particles in all seasons was higher at night than during daytime.The potential source areas of IM-containing particles showed notable narrowing after the BSDW,and the high-value areas were found distributed closer to Chengdu and its surrounding areas.In the winter before the BSDW,most IM-containing particles(>70%)were mixed with organic carbon(OC)particles,and the contributions of OC and mixed organic–elemental carbon(OC-EC)particles increased with aggravation of pollution,whereas OC-EC and Metal particles played a more crucial role in the winter after the BSDW.
基金supported by the International Partnership program of the Chinese Academy of Sciences(170GJHZ2023074GC)National Natural Science Foundation of China(42425706 and 42488201)+1 种基金National Key Research and Development Program of China(2024YFF0807902)Beijing Natural Science Foundation(8242041),and China Postdoctoral Science Foundation(2025M770353).
文摘Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and gridded data)and actual climate data(fixed-point observations near the sampling sites),in northeastern China’s warm temperate zone and analyzed differences in their correlations with tree-ring width index.The results were:(1)Gridded temperature data,as well as precipitation and relative humidity data from the Huailai meteorological station,was more consistent with the actual climate data;in contrast,gridded soil moisture content data showed significant discrepancies.(2)Horizontal distance had a greater impact on the representativeness of actual climate conditions than vertical elevation differences.(3)Differences in consistency between alternative and actual climate data also affected their correlations with tree-ring width indices.In some growing season months,correlation coefficients,both in magnitude and sign,differed significantly from those based on actual data.The selection of different alternative climate datasets can lead to biased results in assessing forest responses to climate change,which is detrimental to the management of forest ecosystems in harsh environments.Therefore,the scientific and rational selection of alternative climate data is essential for dendroecological and climatological research.
文摘This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2.
基金financially supported by National Natural Science Foundation of China (Nos. 81222051 and 81403073)Quality Guarantee System of Chinese Herbal Medicines (No. 201507002)International Quality Standards R&D Program of Traditional Chinese Medicine (No. 201307002)
文摘Cistanche deserticola(CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein,~1H NMR spectroscopy was employed to characterize the chemical profile and to distinguish the different parts, as well as to propose a new processing workflow for CD.Signal assignment was achieved by multiple one and two dimensional NMR spectroscopic techniques in combination with available databases and authentic compounds. The upper parts of the plant were distinguished from the lower parts by combining ~1H NMR spectroscopic dataset with multivariate statistical analysis. A new processing method that hyphenated steaming with freeze-drying, was demonstrated to be superior to either steaming coupled with oven-drying or direct freeze-drying via holistic ~1H NMR-based metabolomic characterization. Phenylethanoid glycosides, mainly echinacoside and acteoside, were screened out and confirmed as the chemical markers responsible for exhibiting the superiority of the new processing workflow, whereas serial primary metabolites, especially carbohydrates and tricarboxylic acid cycle metabolites, were found as the primary molecules governing the discrimination between the upper and lower parts of the plant. Collectively,~1H NMR spectroscopy was demonstrated as a versatile analytical tool to characterize the chemical profile and to guide the indepth exploitation of CD by providing comprehensive qualitative and quantitative information.
文摘A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx 4).
文摘Velvet antler is an important and precious traditional Chinese animal medicine,and was used for strengthening the kidney,anti-fatigue,improving sexual function and so on.But the evaluation methods of velvet antler and the scientific evidence for the use of antler is insufficient.Materials and Vacuum freeze drier was used for dehydration of the fresh antler at-60.,6 pa for 24 h.
基金supported by the National Special Project for Commonweal Industry in China (No. GY-HY201006023,GYHY201106034)the National Support Projects for Science and Technology in China (No.2009BAC53B02)+2 种基金the Project of National Natural Science Foundation of China (No. 41075103)the Application and Foundation Research Program of Sichuan Province (No.2009JY0116)the Project of the Scientific Research Foundation of CUIT (No. KYTZ201008)
文摘The formation and development of weather events has a great impact on the diffusion, accumulation and transport of air pollutants, and causes great changes in the particulate pollution level. It is very important to study their influence on particulate pollution. Lanzhou is one of the most particulate-polluted cities in China and even in the world. Particulate matter （PM） including TSP, PM〉10, PMzs-10, PM2.5 and PM1.0 concentrations were simultaneously measured during 2005-2007 in Lanzhou to evaluate the influence of three kinds of weather events - dost, precipitation and cold front - on the concentrations of PM with different sizes and detect the temporal evolution. The main results are as follows： （1） the PM pollution in Lanzhou during dust events was very heavy and the rate of increase in the concentration of PM2.5-10 was the highest of the five kinds of particles. During dust-storm events, the highest peaks of the concentrations of fine particles （PM2.5 and PM1.0） occurred 3 hr later than those of coarse particles （PM〉10 and PM/.5-10）. （2） The major effect of precipitation events on PM is wet scavenging. The scavenging rates of particles were closely associated with the kinds of precipitation events. The scavenging rates of TSP, PM〉10 and PMa.5-10 by convective precipitation were several times as high as those caused by frontal precipitation for the same precipitation amount, the reason being the different formation mechanism and precipitation characteristics of the two kinds of precipitation. Moreover, there exists a limiting value for the scavenging rates of particles by precipitation. （3） The major effect of cold-front events on particles is clearance. However, during cold-front passages, the PM concentrations could sometimes rise first and decrease afterwards, which is the critical difference in the influence of cold fronts on the concentrations of particulate pollutants vs. gaseous pollutants.
基金funded by the U.S.National Institute of Environmental Health Sciences(ES014218)the U.S.National Cancer Institute(CA94273)
文摘Background： Among numerous health benefits, sports participation has been shown to reduce the risk of overweight and obesity in children and adolescents. Schools represent an ideal environment for increasing sports participation, but it is unclear how access and choice influence participation and whether characteristics of the school sports program differentially influence boys＇ and girls＇ participation. The purpose of this study was to evaluate the characteristics of high school athletic programs and determine the extent to which these characteristics influenced boys＇ and girls＇ sports team participation. Methods： Longitudinal telephone surveys were conducted with 1244 New Hampshire and Vermont students. Students self-reported their sports team participation at baseline （elementary school） and follow-up （high school）. High school personnel were surveyed to assess sports oppor- tunities, which were defined for this analysis as the number of sports offered per 100 students （i.e., choice） and the percent of sports offered that did not restrict the number of players （i.e., access）. Results： Approximately 70% of children participated on at least one sports team, including 73% of boys and 66% of girls. We detected sta- tistically significant interactions between sex and two school opportunity variables： 1） the number of sports offered per 100 students （i.e., choice） and 2） the percent of sports offered that did not restrict the number of players （i.e., access）. After controlling for children＇s baseline sports participation and other covariates, boys were more likely to play on at least one sports team per year if their school did not restrict participation in the most popular sports （relative risk, RR = 1.12, p 〈 0.01）; in contrast, girls were more likely to play on at least one sports team per year if their school offered a wider variety of sports （RR = 1.47, p 〈 0.001）. Conclusion： Sports participation has previously been shown to confer a number of health benefits; as such, school sports programs may be an important, effective, and underused target for public health efforts, including obesity prevention programs. Efforts to increase physical activity among youth should consider both access and choice in school athletic programs. Schools may need to use different strategies to increase sports participation in boys and girls.
基金supported by the National Natural Science Foundation of China(Nos.21205145,21276006,21036009)the Open Funds of State Key Laboratory of Chemo/Biosensing and Chemometrics of Hunan University(No.201111)+1 种基金the Special Fund for Basic Scientific Research of Central Colleges,South-Central University for Nationalities(Nos.CZZ10005 and CZQ11012)the 'Five-twelfth' National Science and Technology Support Program (No.2012BAI27B00)
文摘Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared （NIR） and mid-infrared （MIR） technology combined with supervised pattern recognition based on partial least-squares discriminant analysis （PLSDA） was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct （MSC） fingerprint and second derivative （2nd derivative） fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu.
文摘A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation stages.The remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status information.The late operating trend is predicted by the use of the particle filter algorithm.The rolling bearing full life experimental data validate the proposed method.Further,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability.
