The development of the heart-lung machine made repair of intracardiac lesions possible. One of the key requirements of the heart-lung machine was anticoagulation. Heparin was discovered by a medical student, Jay McLea...The development of the heart-lung machine made repair of intracardiac lesions possible. One of the key requirements of the heart-lung machine was anticoagulation. Heparin was discovered by a medical student, Jay McLean, working in the laboratory of Dr. William Howell at Johns Hopkins. John Gibbon contributed more to the successful development of the heart-lung machine than anyone else. His interest began as a young doctor since 1930s. Gibbon＇s work on the heart-lung machine took place over the next 20 years in laboratories at Massachusetts General Hospital, the University of Pennsylvania, and Thomas Jefferson University In 1937, he reported the first successful demonstration that life could be maintained by an artificial heart and lung, and the native heart and lungs could resume fimction. After World War II, Dr. Gibbon resumed his work and received support from IBM to build a heart-lung machine on a more sophisticated scale. Eventually, the team developed a larger oxygenator that the IBM engineers incorporated into a new machine. On May 6, 1953, Dr. Gibbon performed the first successful operation using an extracorporeal circuit on an 18-year-old girl with a large atrial septal defect. It wasn＇t until 1958, when a system that involved bubbling blood was perfected, that ＂heart-lung＂ machines came of age. Despite so many chill winds and cold rains, ＂heart-lung＂ machine, the budding rose of surgery, was eventually blossom brightly in the radiant rays of sunlight. John Gibbon＇s dream had become a reality. His work serves as an important example to surgeons who are struggling today with the surgical therapies and technologies of tomorrow.展开更多
This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studi...This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored.展开更多
In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size...In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size).The data from measurements show that in the upper atmosphere the existence of an upper jet is important to the transition cyclone.When Mindulle moved to the area of the upper jet entrance,where high-altitude divergence existed, the pumping of the high-altitude divergence would enhance the vertical motion and low-level cyclone convergence. The enhanced vertical motion was confirmed by the simulation results and indicated that the existence of upper divergence enhanced the vertical motion which was favorable for the maintenance of Typhoon Mindulle.The process of extratropical transition (ET) and re-intensification always accompanies the process of cold air invasion. This process enhances the baroclinicity of the atmosphere and the formation of front at high altitudes, which converts baroclinic potential energy into kinetic energy and strengthens the cyclone vortex.The distributions of equivalent potential temperature (θe) and temperature anomalies show that the warm-core of the typhoon at the tropopause aids the re-intensification of the system. As the typhoon reenters the ocean, latent heat flux (LHF) increases in the north and west and the strong reflectivity and vertical motion occur in the east and southeast,and the west.With the re-intensification of the typhoon the wind field evolves from an oval to a circle at the lower atmosphere, the area coverage by high winds increases, and the distribution of the tangential wind shows an asymmetric pattern.展开更多
This invited paper reviews recent initiatives in teaching about randomized field trials at the graduate level in education research. Reports in a book on randomized trials by Mosteller and Boruch are used as a benchma...This invited paper reviews recent initiatives in teaching about randomized field trials at the graduate level in education research. Reports in a book on randomized trials by Mosteller and Boruch are used as a benchmark. The initiatives have been driven heavily by recent governmental emphasis on ＂evidence based policy＂ in education, criminology, welfare and other sectors. This policy has been backed, in the US at least, by substantial investments in mounting randomized controlled trials to evaluate curriculum packages and programs in grades K-12, crime prevention programs, welfare, and other work. Accelerated growth in randomized trials has entailed cross discipline pre-doctoral and post-doctoral institutes and graduate education programs aimed at enhancing the quality in trial design, execution, and analysis of results. Specific illustrations of graduate education in this area of statistics are taken mainly from experience at the University of Pennsylvania＇s Graduate School of Education and selected other institutions.展开更多
The paper analyzes John Presper Eckert and John William Mauchly＇s endeavours to design, sell, and build the revolutionary new technology of the first-large and commercial computers. It discusses how Eckert and Mauchl...The paper analyzes John Presper Eckert and John William Mauchly＇s endeavours to design, sell, and build the revolutionary new technology of the first-large and commercial computers. It discusses how Eckert and Mauchly＇s conceptualization of the computer grew out of their Electronic Numerical Integrator and Calculator （ENIAC） and Electronic Discrete Variable Automatic Computer （EDVAC） projects at University of Pennsylvania. They incorporated their own business to gain profit from production and attain the freedom needed to develop their revolutionary new computer technology through a series of small and separate computer projects with private and government customers. The paper approaches innovation as a chaotic process and uses uncertainty to conceptualize the basic relations between actors and organizations.展开更多
Alternative Low-Input Agriculture Systems （ALIAS） center advocates organic and sustainable food production system through farm/field demonstration and piloting. The center undertakes activities, including research a...Alternative Low-Input Agriculture Systems （ALIAS） center advocates organic and sustainable food production system through farm/field demonstration and piloting. The center undertakes activities, including research and development, extension and training, technology dissemination, linkaging and promotional activities. The study established a campus-based demonstration technology showcasing ALIAS to facilitate easy technology diffusion. The objectives of this research were to promote： （1） bio-fertilizers and plant-based pesticides in managing insect pests and diseases of organic vegetables and fruit crops; （2） lotus-tilapia integration as a new modality of farming system in frequently flooded areas; （3） honeybee as pollinators to enhance productivity of organic vegetable and fruit crops; （4） Adlai as intercrop to organic vegetable and fruit crops in support to rice sufficiency; （5） native chicken-coffee integration. The results show that： （1） microbial inoculants and plant-based pesticides are effective in controlling diseases and insect pest, respectively; （2） lotus integration in tilapia production system have no negative effect on the tilapia yield; （3） honeybees as pollinators enhances fruit setting by 42%-68% in different crops; （4） Adlai is a viable intercrop for organic vegetable and fruit crops; （5） native chicken integration was found to be beneficial in terms of soil fertility, insect pest control, natural weeding practices and cultivation in the coffee plantation.展开更多
文摘The development of the heart-lung machine made repair of intracardiac lesions possible. One of the key requirements of the heart-lung machine was anticoagulation. Heparin was discovered by a medical student, Jay McLean, working in the laboratory of Dr. William Howell at Johns Hopkins. John Gibbon contributed more to the successful development of the heart-lung machine than anyone else. His interest began as a young doctor since 1930s. Gibbon＇s work on the heart-lung machine took place over the next 20 years in laboratories at Massachusetts General Hospital, the University of Pennsylvania, and Thomas Jefferson University In 1937, he reported the first successful demonstration that life could be maintained by an artificial heart and lung, and the native heart and lungs could resume fimction. After World War II, Dr. Gibbon resumed his work and received support from IBM to build a heart-lung machine on a more sophisticated scale. Eventually, the team developed a larger oxygenator that the IBM engineers incorporated into a new machine. On May 6, 1953, Dr. Gibbon performed the first successful operation using an extracorporeal circuit on an 18-year-old girl with a large atrial septal defect. It wasn＇t until 1958, when a system that involved bubbling blood was perfected, that ＂heart-lung＂ machines came of age. Despite so many chill winds and cold rains, ＂heart-lung＂ machine, the budding rose of surgery, was eventually blossom brightly in the radiant rays of sunlight. John Gibbon＇s dream had become a reality. His work serves as an important example to surgeons who are struggling today with the surgical therapies and technologies of tomorrow.
基金Under the jointly auspices of the Special Public Research for Meteorological Industry (No. GYHY200806009)Wind Energy Resources Detailed Survey and Assessment WorkEU-China Energy and Environment Program (No. Europe Aid/ 123310/D/Ser/CN)
文摘This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored.
基金supported by the National Natural Science Foundation of China(Nos.40876004,40890155 and 40675060)National 973 Project(Nos.2009CB-421500 and 2007CB411801)
文摘In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size).The data from measurements show that in the upper atmosphere the existence of an upper jet is important to the transition cyclone.When Mindulle moved to the area of the upper jet entrance,where high-altitude divergence existed, the pumping of the high-altitude divergence would enhance the vertical motion and low-level cyclone convergence. The enhanced vertical motion was confirmed by the simulation results and indicated that the existence of upper divergence enhanced the vertical motion which was favorable for the maintenance of Typhoon Mindulle.The process of extratropical transition (ET) and re-intensification always accompanies the process of cold air invasion. This process enhances the baroclinicity of the atmosphere and the formation of front at high altitudes, which converts baroclinic potential energy into kinetic energy and strengthens the cyclone vortex.The distributions of equivalent potential temperature (θe) and temperature anomalies show that the warm-core of the typhoon at the tropopause aids the re-intensification of the system. As the typhoon reenters the ocean, latent heat flux (LHF) increases in the north and west and the strong reflectivity and vertical motion occur in the east and southeast,and the west.With the re-intensification of the typhoon the wind field evolves from an oval to a circle at the lower atmosphere, the area coverage by high winds increases, and the distribution of the tangential wind shows an asymmetric pattern.
文摘This invited paper reviews recent initiatives in teaching about randomized field trials at the graduate level in education research. Reports in a book on randomized trials by Mosteller and Boruch are used as a benchmark. The initiatives have been driven heavily by recent governmental emphasis on ＂evidence based policy＂ in education, criminology, welfare and other sectors. This policy has been backed, in the US at least, by substantial investments in mounting randomized controlled trials to evaluate curriculum packages and programs in grades K-12, crime prevention programs, welfare, and other work. Accelerated growth in randomized trials has entailed cross discipline pre-doctoral and post-doctoral institutes and graduate education programs aimed at enhancing the quality in trial design, execution, and analysis of results. Specific illustrations of graduate education in this area of statistics are taken mainly from experience at the University of Pennsylvania＇s Graduate School of Education and selected other institutions.
文摘The paper analyzes John Presper Eckert and John William Mauchly＇s endeavours to design, sell, and build the revolutionary new technology of the first-large and commercial computers. It discusses how Eckert and Mauchly＇s conceptualization of the computer grew out of their Electronic Numerical Integrator and Calculator （ENIAC） and Electronic Discrete Variable Automatic Computer （EDVAC） projects at University of Pennsylvania. They incorporated their own business to gain profit from production and attain the freedom needed to develop their revolutionary new computer technology through a series of small and separate computer projects with private and government customers. The paper approaches innovation as a chaotic process and uses uncertainty to conceptualize the basic relations between actors and organizations.
文摘Alternative Low-Input Agriculture Systems （ALIAS） center advocates organic and sustainable food production system through farm/field demonstration and piloting. The center undertakes activities, including research and development, extension and training, technology dissemination, linkaging and promotional activities. The study established a campus-based demonstration technology showcasing ALIAS to facilitate easy technology diffusion. The objectives of this research were to promote： （1） bio-fertilizers and plant-based pesticides in managing insect pests and diseases of organic vegetables and fruit crops; （2） lotus-tilapia integration as a new modality of farming system in frequently flooded areas; （3） honeybee as pollinators to enhance productivity of organic vegetable and fruit crops; （4） Adlai as intercrop to organic vegetable and fruit crops in support to rice sufficiency; （5） native chicken-coffee integration. The results show that： （1） microbial inoculants and plant-based pesticides are effective in controlling diseases and insect pest, respectively; （2） lotus integration in tilapia production system have no negative effect on the tilapia yield; （3） honeybees as pollinators enhances fruit setting by 42%-68% in different crops; （4） Adlai is a viable intercrop for organic vegetable and fruit crops; （5） native chicken integration was found to be beneficial in terms of soil fertility, insect pest control, natural weeding practices and cultivation in the coffee plantation.
