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The first case of the unstable Hb Genova as a result of sporadic mutation is described. It is found in a 3-year-old Canadian boy of East Indian extraction with chronic Heinz body haemolytic anaemia. 相似文献
35.
The thermal energy available from high-temperature magma is calculated to be 8 × 1014 kcal/km3 and an upper bound for volcanic energy of 3 × 1018 kcal/volcano is determined. Approximately one-third of the energy may be obtained between about 750 and 1150 °C (i.e. above the solidification temperature of the magma), while the remaining two-thirds is available from magma in the solid state between ambient and around 750 °C. Gas dissolved in the magma possesses about 4% of the thermal energy and a large portion of that energy is potentially available as high-temperature steam. After removal of water, the gas remaining is a low-Btu gas with a heat of combustion of about 0.3 kcal/l. Utilization of both the thermal and combustion energy is the subject of current research projects. 相似文献
36.
Three representatives of a novel class of amide (isopeptide) glycoconjugates have been synthesised: N alpha-D-galacturonoyl-L-lysine and N epsilon-D-galacturonoyl-L-lysine and N epsilon-D-polygalacturonoyl-L-lysine. Galacturonoyl-lysine amide bonds were labile in 2 M trifluoroacetic acid at 120 degrees and in alkali, but relatively stable in cold acid. The amide bonds were resistant to digestion by Driselase, Pronase and trypsin. The polysaccharide backbone of N epsilon-D-polygalacturonoyl-L-lysine was hydrolysed by Driselase to yield two major ninhydrin-positive compounds which were shown by 1H and 13C NMR spectroscopy to be tri- and tetra-alpha-(1-->4)-D-galacturonoyl-L-lysines. To investigate the possible natural occurrence of N-galacturonoyl isopeptide bonds, we fed cell-suspension cultures of spinach and tomato with D-[6-14C]glucuronic acid, which radio-labels pectic polysaccharides. The radioactive cell walls were digested with, sequentially, Driselase, mild acid, and proteinases. On electrophoresis at pH 2.0, several of the radioactive digestion-products were cathodic. Some of the cathodic products yielded [14C]galacturonic acid upon complete acid hydrolysis. The existence of these products is compatible with the presence of novel N-galacturonoyl isopeptide bonds, which could serve as cross-links in plant cell walls. 相似文献
37.
Electrochromic fabric devices represent a further extension to the plethora of available literature on conductive fabrics. This article contains a brief overview of electrochromic devices, electrochromic polymers, conductive materials, conductive fabrics, and electrochromic fabric devices. A tabulated list of the perceived colour of a number of electrochromic polymers that is contained herein is designed to serve as an aide to colour mixing studies. The challenges of optimisation and commercialisatiion of electrochromic fabric devices and their mitigating factors are conjectured, along with some future potential applications for electrochromic fabric device technologies. 相似文献
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Here, we describe the development of a reacting flow multi-species/combustion methodology, implemented as an extension to the differential reduced ejector analysis (DREA) computer program [Mathematical and computer modeling, vol. 31, 2000, p. 21; Appl. Math. Model. 25 (2001) 427; Comput. Math. Appl. 43(10–11); NASA Contractor Report, 1998]. Use of the single fluid IVP solver framework that was developed for the original DREA model has been directly coupled into the combustion formulation. With these modifications, the analysis has an elementary single step reaction Fuel+Oxidizer→Product combustion capability. Though approximate in nature, the simplicity and efficiency of the DREA formulation make it suitable for its original niche, namely design and preliminary design environments where more complex and expensive models may be inappropriate. 相似文献
39.
David A. Conner Ph.D. P.E. Gary J. Grimes Ph.D. Jay Goldman D.SC. P.E. 《Journal of Systems Integration》2000,10(1):81-94
For telemedicine to reach its potential in the Internet2 environment,significant progress must be made in a number of areas. The emergingtelecommunications will include the Internet2 between medicalinstitutions and emerging broadband loop and wireless technologiesfor interconnections to homes. Within the technical environment,problems that must be addressed include the development of robotic-controlled,remote-monitoring devices unique to the various medical specialties;the encoding, transmission, and decoding of raw data specificto the specialized needs of various medical application areas;and the reduction of data for storage and retrieval in patientrecords. Institutionally, human factor and information accessissues with respect to physicians, patients, and non-physicianhealthcare providers must be addressed; healthcare insuranceprovider policies, government regulation, and state licensinglaws must be adapted for a new paradigm of healthcare delivery;and the philosophy of capital investment for the delivery ofhealthcare must be revised.Many current practiceswill be supplanted by home healthcare alternatives, the use ofpatient-initiated preventive healthcare initiatives, and remote-clinicactivity. These applications will result in central record archivingsystems; the need for encryption schemes, virus protection, andvandalism protection; extensive, additional connectivity betweenhealthcare providers and professionals; and new commercial playersin the healthcare arena.The hot applicationareas will include women's health, children's health, healthcarefor senior citizens, home healthcare, well-patient monitoring,and early-detection of medical problems. 相似文献
40.
Quarterly Time-Series Forecasting With Neural Networks 总被引:2,自引:0,他引:2
Forecasting of time series that have seasonal and other variations remains an important problem for forecasters. This paper presents a neural network (NN) approach to forecasting quarterly time series. With a large data set of 756 quarterly time series from the M3 forecasting competition, we conduct a comprehensive investigation of the effectiveness of several data preprocessing and modeling approaches. We consider two data preprocessing methods and 48 NN models with different possible combinations of lagged observations, seasonal dummy variables, trigonometric variables, and time index as inputs to the NN. Both parametric and nonparametric statistical analyses are performed to identify the best models under different circumstances and categorize similar models. Results indicate that simpler models, in general, outperform more complex models. In addition, data preprocessing especially with deseasonalization and detrending is very helpful in improving NN performance. Practical guidelines are also provided. 相似文献