Percutaneous endoscopic gastrostomy (PEG) is the preferred route of feeding and nutritional support in patients with a functional gastrointestinal system who require long-term enteral nutrition. Besides its well-known...Percutaneous endoscopic gastrostomy (PEG) is the preferred route of feeding and nutritional support in patients with a functional gastrointestinal system who require long-term enteral nutrition. Besides its well-known advantages over parenteral nutrition, PEG offers superior access to the gastrointestinal system over surgical methods. Considering that nowadays PEG tube placement is one of the most common endoscopic procedures performed worldwide, knowing its indications and contraindications is of paramount importance in current medicine. PEG tubes are sometimes placed inappropriately in patients unable to tolerate adequate oral intake because of incorrect and unrealistic understanding of their indications and what they can accomplish. Broadly, the two main indications of PEG tube placement are enteral feeding and stomach decompression. On the other hand, distal enteral obstruction, severe uncorrectable coagulopathy and hemodynamic instability constitute the main absolute contraindications for PEG tube placement in hospitalized patients. Although generally considered to be a safe procedure, there is the potential for both minor and major complications. Awareness of these potential complications, as well as understanding routine aftercare of the catheter, can improve the quality of care for patients with a PEG tube. These complications can generally be classified into three major categories: endoscopic technical difficulties, PEG procedure-related complications and late complications associated with PEG tube use and wound care. In this review we describe a variety of minor and major tube-related complications as well as strategies for their management and avoidance. Different methods of percutaneous PEG tube placement into the stomach have been described in the literature with the “pull” technique being the most common method. In the last section of this review, the reader is presented with a brief discussion of these procedures, techniques and related issues. Despite the mentioned PEG tube placeme展开更多
The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of sta...The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of standard stars for flux calibration, we use the photometric data of 15 intermediate bands in the Beijing-Arizona-Taipei-Connecticut （BATC） survey to calibrate the spectra. In to- tal, 59 spectra located in the bulge and disk of the galaxy are obtained. Kinematic and stellar population properties of the stellar content are derived with these spectra. We obtain the global velocity field and calculate corresponding rotation velocities out to about 7 kpc along the major axis. These rotation velocity measurements comple- ment those of the gas content, such as the H I and CO. The radial velocity dispersion shows that the stars in the bulge are more dynamically thermal and the disk is more rotationally-supported. The age distribution shows that the bulge was formed about 12 Gyr ago, the disk is relatively younger and the ages of some regions along the spi- ral arms can reach as young as about 1 Gyr. These young stellar populations have a relatively richer abundance and larger reddening. The overall average metallicity of the galaxy approximates the solar metallicity and a very weak abundance gradient is gained. The reddening map gives a picture of a dust-free bulge and a distinct dusty ring in the disk.展开更多
The airlines need to select the optional equipment according to their individual development demands and the manufacture′s standard specification manual when purchasing a new airplane.For this customization process,t...The airlines need to select the optional equipment according to their individual development demands and the manufacture′s standard specification manual when purchasing a new airplane.For this customization process,the selection theory is mainly based on qualitative analysis and quantitative analysis.The grey incidence analysis(GIA)is used for modeling,which evaluates the correlations between optional equipment and airlines′individual demands.Meanwhile,the customization demands are quantitatively processed as different weights in evaluation index system with analytical hierarchy process.Then,the value of grey incidence degree is obtained which shows whether the optional equipment is on the purchasing list or not.Finally,two airlines′customization demands are applied in the example of aircraft cabin′s seats,so two different purchasing priorities and equipment installation lists can be obtained.The results and comparisons verify the reasonable of modeling,which provides an objective scheme of aircraft equipment selection.展开更多
AIM: To generate novel tumor models for preclinicalvalidation of biomarkers that allow drug response prediction and individual therapeutic decisions.METHODS: Cell line establishment was conducted by both direct in vit...AIM: To generate novel tumor models for preclinicalvalidation of biomarkers that allow drug response prediction and individual therapeutic decisions.METHODS: Cell line establishment was conducted by both direct in vitro culturing and in vivo xenografting followed by in vitro culturing procedure.A comprehensive characterization was subsequently performed.This included quality control,consisting of the confirmation of human and colorectal cancer(CRC) origin by DNA fingerprint and epithelial cell adhesion molecule(EpC AM) staining,as well as mycoplasma and human virus testing.Phenotypic analysis was done by light microscopy and multicolor flow cytometry.Histopathological examination(β-catenin and cytokeratin staining) was conducted in direct comparison to parental tumor tissues.Extensive molecular-pathological profiling included mutation analysis for CRC-associated driver mutations,assessment of chromosomal and microsatellite instability,and the grade of CpG island methylation.Additionally,an arraybased comparative genomic hybridization analysis was performed.Drug responsiveness was assessed for a panel of classical and novel substances in clinical use for the treatment of solid cancers.Finally,tumorigenicity of the cell lines was tested by xenografting into immunocompromised nude mice.RESULTS: Herein we describe the establishment of three ultra-low passage cell lines from two individual patients suffering from sporadic CRC.One cell line was derived directly from an early stage case(HROC18),whereas two cell lines could be established both direct from patient material and after xenografting from a late stage tumor(HROC32).All cell lines were free of contaminating mycoplasma and viruses.Molecularpathological analysis allowed all cell lines to be classified as chromosomal instable(CIN+).They were aneuploid,with CpG island promoter methylation and microsatellite instability being absent.The following mutational profile was observed both in the cell lines and the parental tumor tissue: HROC18: APCmut,p53 mut,K-raswt; HR展开更多
We studied the perception of forest-dependent communities on climate change with its associated risk and their adaptation strategies in Mizoram, Northeast India. A total of 360 respondents (household heads) were rando...We studied the perception of forest-dependent communities on climate change with its associated risk and their adaptation strategies in Mizoram, Northeast India. A total of 360 respondents (household heads) were randomly selected from 24 villages across the three different agro-climatic zones prevalent. The community perceived awareness of climate change phenomena in the region with a positive correlation between age, education and occupation of the respondents. The overall perception of climate change in temperature was medium (0.49), while low for change in precipitation (0.26) and seasonal durability (0.23). The community showed over-all low score of perception on risk of climate change (0.10) where risk on livelihood and socio-economic factors was higher than risk to environment or forest. Perception on impact of climate change was high for forest abi-otic ecological factors (0.66) and flora and fauna (0.62), while medium on livelihood of forest-dependent communities (0.44). The majority (more than 75%) of the respondents agreed that human beings are involved and responsible for climate change. Adoption of adaptive strategies to cope climate change ranged from 0.07 to 0.91, amongst which zero tillage, use of traditional knowledge, forest fire prevention, soil and water conservation techniques, agroforestry practices and social forestry are popular. However, rain water harvesting and investments for crop insurance were adopted on low scores clearly implied by the educational and socio-economic status of the farmers in the majority. The study brings out the knowledge and perceptions to climate change by forest-dependent communities and their adaptive strategies to cope had been assessed. The finding results seek the attention of researchers and policy makers to integrate technological and financial interventions in supporting farmer’s effort to cope with climate change with a long term objective for improving their livelihood and climate sensitive resources at the same time.展开更多
This paper addresses the robust attitude control problem for quadrotors subject to model mismatch and disturbances.A dynamic inversion based attitude control scheme is proposed,which consists of an outer loop attitude...This paper addresses the robust attitude control problem for quadrotors subject to model mismatch and disturbances.A dynamic inversion based attitude control scheme is proposed,which consists of an outer loop attitude controller and an inner loop angular acceleration controller.The attitude controller is designed based on the Nonlinear Dynamic Inversion(NDI)to precisely linearize the nonlinear dynamics between the angular acceleration and the attitude.An onboard actuator model-based Incremental Nonlinear Dynamic Inversion(INDI)controller is designed in the angular acceleration control loop to improve the robustness against the model mismatch and disturbances.Meanwhile,the onboard actuator model with a modified structure eliminates the oscillation phenomenon when the sampling rate of the controller is higher than that of the actuator.Numerical simulations and flight tests demonstrate the effectiveness and robustness of the proposed controller in comparison with the PID controller.展开更多
20071738 Cao Shuhui(School of Earth and Space Science,Peking University,Beijing 100871,China);Zhang Lifei A Raman Spectroscopic Study of Phengite under High Pressure(Acta Petrologica et Mineralogica,ISSN1000-6524,CN11...20071738 Cao Shuhui(School of Earth and Space Science,Peking University,Beijing 100871,China);Zhang Lifei A Raman Spectroscopic Study of Phengite under High Pressure(Acta Petrologica et Mineralogica,ISSN1000-6524,CN11-1966/P,25(1),2006,p.71-76,4 illus.,2 tables,16 refs.)Key words:phengite,Raman spectra Within the diamond展开更多
Using AHP(Analytic Hierarchy Process)and GCA(Grey Comprehensive Analysis),this article measures the degree of urban-rural coordinated development of Chongqing City,and establishes GARCH model to analyze its dynamic fe...Using AHP(Analytic Hierarchy Process)and GCA(Grey Comprehensive Analysis),this article measures the degree of urban-rural coordinated development of Chongqing City,and establishes GARCH model to analyze its dynamic feature.The results show that urban-rural coordination degree of Chongqing City tended to decline year by year in the period 1985-2010 on the whole;after it became a municipality directly under the Central Government,the average annual rate of decline reached 1.78%.Further,from GARCH modeling analysis,there is no"clustering"in urban-rural coordination degree of Chongqing City,and the impact of fluctuation state in the past on the future will gradually intensify.There is no "leverage effect"in urban-rural coordination degree of Chongqing City,and if the government does not exert"external force",urban-rural coordination degree will decline year by year.But in the long run,urban-rural coordination degree will gradually converge to the equilibrium level.Based on this,we propose to strengthen institutional innovation and help propel coordinated urban and rural development,in terms of employment,social security,finance,land management and use.展开更多
目的评估万古霉素群体药动学软件(JPKD-vancomycin)在中国人群的预测,并验证其临床应用效果。方法根据万古霉素群体药动学(PPK)研究模型,在JPKD的自定义板块重新定义新的万古霉素药动学模型。利用贝叶斯反馈法方法估算万古霉素药动学参...目的评估万古霉素群体药动学软件(JPKD-vancomycin)在中国人群的预测,并验证其临床应用效果。方法根据万古霉素群体药动学(PPK)研究模型,在JPKD的自定义板块重新定义新的万古霉素药动学模型。利用贝叶斯反馈法方法估算万古霉素药动学参数。收集我院接受万古霉素治疗的住院患者,排除严重肾功能不全者(肌酐清除率<50 m L·min-1)以及合并用药者(甘露醇、多巴胺、多巴酚丁胺、呋塞米),筛选出有调整过万古霉素剂量且有稳态谷浓度测定数据者68例。将患者第1次的万古霉素给药剂量及相关的个体化信息输入JPKD-vancomycin,使用贝叶斯反馈法估算出患者个人的药动学参数,再输入第2次的万古霉素给药剂量,输注时间和给药间隔,由软件依据上述参数预测出更改剂量后的谷浓度数据,计算预测浓度与实测浓度之间的权重偏差(WRES),考察该软件的预测能力,并通过临床病例验证。结果所有患者使用万古霉素后的实际稳态谷浓度为(11.71±5.15)mg·L-1,以JPKD-vancomycin运算后预测的谷浓度为(11.55±5.19)mg·L-1,WRES为(11.6±7.9)%。模型对中国人群的预测能力良好;经临床初步验证,效果较为满意。结论 JPKD-vancomycin对中国人群万古霉素稳态谷浓度有良好的预测能力。本研究建立的JPKD-vancomycin个体化给药模式,有助于指导临床合理用药。展开更多
文摘Percutaneous endoscopic gastrostomy (PEG) is the preferred route of feeding and nutritional support in patients with a functional gastrointestinal system who require long-term enteral nutrition. Besides its well-known advantages over parenteral nutrition, PEG offers superior access to the gastrointestinal system over surgical methods. Considering that nowadays PEG tube placement is one of the most common endoscopic procedures performed worldwide, knowing its indications and contraindications is of paramount importance in current medicine. PEG tubes are sometimes placed inappropriately in patients unable to tolerate adequate oral intake because of incorrect and unrealistic understanding of their indications and what they can accomplish. Broadly, the two main indications of PEG tube placement are enteral feeding and stomach decompression. On the other hand, distal enteral obstruction, severe uncorrectable coagulopathy and hemodynamic instability constitute the main absolute contraindications for PEG tube placement in hospitalized patients. Although generally considered to be a safe procedure, there is the potential for both minor and major complications. Awareness of these potential complications, as well as understanding routine aftercare of the catheter, can improve the quality of care for patients with a PEG tube. These complications can generally be classified into three major categories: endoscopic technical difficulties, PEG procedure-related complications and late complications associated with PEG tube use and wound care. In this review we describe a variety of minor and major tube-related complications as well as strategies for their management and avoidance. Different methods of percutaneous PEG tube placement into the stomach have been described in the literature with the “pull” technique being the most common method. In the last section of this review, the reader is presented with a brief discussion of these procedures, techniques and related issues. Despite the mentioned PEG tube placeme
基金supported by the National Natural Science Foundation of China (GrantNos. 10873016,10633020,10603006,10803007,10903011,11003021 and 11073032)by the National Basic Research Program of China (973 Program Nos. 2007CB815403,2010CB833004 and 2009CB82480X)
文摘The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of standard stars for flux calibration, we use the photometric data of 15 intermediate bands in the Beijing-Arizona-Taipei-Connecticut （BATC） survey to calibrate the spectra. In to- tal, 59 spectra located in the bulge and disk of the galaxy are obtained. Kinematic and stellar population properties of the stellar content are derived with these spectra. We obtain the global velocity field and calculate corresponding rotation velocities out to about 7 kpc along the major axis. These rotation velocity measurements comple- ment those of the gas content, such as the H I and CO. The radial velocity dispersion shows that the stars in the bulge are more dynamically thermal and the disk is more rotationally-supported. The age distribution shows that the bulge was formed about 12 Gyr ago, the disk is relatively younger and the ages of some regions along the spi- ral arms can reach as young as about 1 Gyr. These young stellar populations have a relatively richer abundance and larger reddening. The overall average metallicity of the galaxy approximates the solar metallicity and a very weak abundance gradient is gained. The reddening map gives a picture of a dust-free bulge and a distinct dusty ring in the disk.
文摘The airlines need to select the optional equipment according to their individual development demands and the manufacture′s standard specification manual when purchasing a new airplane.For this customization process,the selection theory is mainly based on qualitative analysis and quantitative analysis.The grey incidence analysis(GIA)is used for modeling,which evaluates the correlations between optional equipment and airlines′individual demands.Meanwhile,the customization demands are quantitatively processed as different weights in evaluation index system with analytical hierarchy process.Then,the value of grey incidence degree is obtained which shows whether the optional equipment is on the purchasing list or not.Finally,two airlines′customization demands are applied in the example of aircraft cabin′s seats,so two different purchasing priorities and equipment installation lists can be obtained.The results and comparisons verify the reasonable of modeling,which provides an objective scheme of aircraft equipment selection.
文摘AIM: To generate novel tumor models for preclinicalvalidation of biomarkers that allow drug response prediction and individual therapeutic decisions.METHODS: Cell line establishment was conducted by both direct in vitro culturing and in vivo xenografting followed by in vitro culturing procedure.A comprehensive characterization was subsequently performed.This included quality control,consisting of the confirmation of human and colorectal cancer(CRC) origin by DNA fingerprint and epithelial cell adhesion molecule(EpC AM) staining,as well as mycoplasma and human virus testing.Phenotypic analysis was done by light microscopy and multicolor flow cytometry.Histopathological examination(β-catenin and cytokeratin staining) was conducted in direct comparison to parental tumor tissues.Extensive molecular-pathological profiling included mutation analysis for CRC-associated driver mutations,assessment of chromosomal and microsatellite instability,and the grade of CpG island methylation.Additionally,an arraybased comparative genomic hybridization analysis was performed.Drug responsiveness was assessed for a panel of classical and novel substances in clinical use for the treatment of solid cancers.Finally,tumorigenicity of the cell lines was tested by xenografting into immunocompromised nude mice.RESULTS: Herein we describe the establishment of three ultra-low passage cell lines from two individual patients suffering from sporadic CRC.One cell line was derived directly from an early stage case(HROC18),whereas two cell lines could be established both direct from patient material and after xenografting from a late stage tumor(HROC32).All cell lines were free of contaminating mycoplasma and viruses.Molecularpathological analysis allowed all cell lines to be classified as chromosomal instable(CIN+).They were aneuploid,with CpG island promoter methylation and microsatellite instability being absent.The following mutational profile was observed both in the cell lines and the parental tumor tissue: HROC18: APCmut,p53 mut,K-raswt; HR
文摘We studied the perception of forest-dependent communities on climate change with its associated risk and their adaptation strategies in Mizoram, Northeast India. A total of 360 respondents (household heads) were randomly selected from 24 villages across the three different agro-climatic zones prevalent. The community perceived awareness of climate change phenomena in the region with a positive correlation between age, education and occupation of the respondents. The overall perception of climate change in temperature was medium (0.49), while low for change in precipitation (0.26) and seasonal durability (0.23). The community showed over-all low score of perception on risk of climate change (0.10) where risk on livelihood and socio-economic factors was higher than risk to environment or forest. Perception on impact of climate change was high for forest abi-otic ecological factors (0.66) and flora and fauna (0.62), while medium on livelihood of forest-dependent communities (0.44). The majority (more than 75%) of the respondents agreed that human beings are involved and responsible for climate change. Adoption of adaptive strategies to cope climate change ranged from 0.07 to 0.91, amongst which zero tillage, use of traditional knowledge, forest fire prevention, soil and water conservation techniques, agroforestry practices and social forestry are popular. However, rain water harvesting and investments for crop insurance were adopted on low scores clearly implied by the educational and socio-economic status of the farmers in the majority. The study brings out the knowledge and perceptions to climate change by forest-dependent communities and their adaptive strategies to cope had been assessed. The finding results seek the attention of researchers and policy makers to integrate technological and financial interventions in supporting farmer’s effort to cope with climate change with a long term objective for improving their livelihood and climate sensitive resources at the same time.
基金co-supported by the National Natural Science Foundation of China(Nos.61803009,61903084)the Fundamental Research Funds for the Central Universities of China(No.YWF-20-BJ-J-542)。
文摘This paper addresses the robust attitude control problem for quadrotors subject to model mismatch and disturbances.A dynamic inversion based attitude control scheme is proposed,which consists of an outer loop attitude controller and an inner loop angular acceleration controller.The attitude controller is designed based on the Nonlinear Dynamic Inversion(NDI)to precisely linearize the nonlinear dynamics between the angular acceleration and the attitude.An onboard actuator model-based Incremental Nonlinear Dynamic Inversion(INDI)controller is designed in the angular acceleration control loop to improve the robustness against the model mismatch and disturbances.Meanwhile,the onboard actuator model with a modified structure eliminates the oscillation phenomenon when the sampling rate of the controller is higher than that of the actuator.Numerical simulations and flight tests demonstrate the effectiveness and robustness of the proposed controller in comparison with the PID controller.
文摘20071738 Cao Shuhui(School of Earth and Space Science,Peking University,Beijing 100871,China);Zhang Lifei A Raman Spectroscopic Study of Phengite under High Pressure(Acta Petrologica et Mineralogica,ISSN1000-6524,CN11-1966/P,25(1),2006,p.71-76,4 illus.,2 tables,16 refs.)Key words:phengite,Raman spectra Within the diamond
基金Supported by Key Chongqing Municipal Humanities and Social Sciences Research Base Project in Southwest University(SWU0810026)the Fundamental Research Funds for the Central Universities(SWU1209457and SWU0909510)+4 种基金National Soft Science Fund(2007GXS3D094)Youth Fund Project of Southwest Normal University(SWU07106)Chongqing Soft Science Project(CSTC,2009CE9016)2012 Shizhu Base Science and Technology Innovation Special Fund Projects(sz201208)Social Science Planning Fund of the Ministry of Education(07JA790104)
文摘Using AHP(Analytic Hierarchy Process)and GCA(Grey Comprehensive Analysis),this article measures the degree of urban-rural coordinated development of Chongqing City,and establishes GARCH model to analyze its dynamic feature.The results show that urban-rural coordination degree of Chongqing City tended to decline year by year in the period 1985-2010 on the whole;after it became a municipality directly under the Central Government,the average annual rate of decline reached 1.78%.Further,from GARCH modeling analysis,there is no"clustering"in urban-rural coordination degree of Chongqing City,and the impact of fluctuation state in the past on the future will gradually intensify.There is no "leverage effect"in urban-rural coordination degree of Chongqing City,and if the government does not exert"external force",urban-rural coordination degree will decline year by year.But in the long run,urban-rural coordination degree will gradually converge to the equilibrium level.Based on this,we propose to strengthen institutional innovation and help propel coordinated urban and rural development,in terms of employment,social security,finance,land management and use.
文摘目的评估万古霉素群体药动学软件(JPKD-vancomycin)在中国人群的预测,并验证其临床应用效果。方法根据万古霉素群体药动学(PPK)研究模型,在JPKD的自定义板块重新定义新的万古霉素药动学模型。利用贝叶斯反馈法方法估算万古霉素药动学参数。收集我院接受万古霉素治疗的住院患者,排除严重肾功能不全者(肌酐清除率<50 m L·min-1)以及合并用药者(甘露醇、多巴胺、多巴酚丁胺、呋塞米),筛选出有调整过万古霉素剂量且有稳态谷浓度测定数据者68例。将患者第1次的万古霉素给药剂量及相关的个体化信息输入JPKD-vancomycin,使用贝叶斯反馈法估算出患者个人的药动学参数,再输入第2次的万古霉素给药剂量,输注时间和给药间隔,由软件依据上述参数预测出更改剂量后的谷浓度数据,计算预测浓度与实测浓度之间的权重偏差(WRES),考察该软件的预测能力,并通过临床病例验证。结果所有患者使用万古霉素后的实际稳态谷浓度为(11.71±5.15)mg·L-1,以JPKD-vancomycin运算后预测的谷浓度为(11.55±5.19)mg·L-1,WRES为(11.6±7.9)%。模型对中国人群的预测能力良好;经临床初步验证,效果较为满意。结论 JPKD-vancomycin对中国人群万古霉素稳态谷浓度有良好的预测能力。本研究建立的JPKD-vancomycin个体化给药模式,有助于指导临床合理用药。
