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排序方式: 共有34条查询结果,搜索用时 15 毫秒
1.
Bruce Tonn K.C. Healy Amy Gibson Ashutosh Ashish Preston Cody Drew Beres Sam Lulla Jim Mazur A.J. Ritter 《Energy Policy》2009
This paper presents United States energy portfolios for the year 2030, developed from seven different Perspectives. The Perspectives are characterized by different weights placed on fourteen defining values (e.g., cost, social acceptance). The portfolios were constructed to achieve three primary goals, energy independence, energy security, and greenhouse gas reductions. The portfolios are also evaluated over a comprehensive set of secondary criteria (e.g., economic growth, technical feasibility). It is found that very different portfolios based on very different defining values can achieve the three primary goals. Commonalities among the portfolios include reliance upon cellulosic ethanol, nuclear power, and energy efficiency to meet year 2030 energy demands. It is concluded that the US energy portfolio must be diverse and to achieve national energy goals will require an explicit statement of goals, a strong role for government, and coordinated action across society. 相似文献
2.
T Tonn C Esser EM Schneider W Steinmann-Steiner-Haldenst?tt E Gleichmann 《Canadian Metallurgical Quarterly》1996,104(4):422-426
OBJECTIVE: To evaluate the distribution of mepivacaine hydrochloride after distal interphalangeal (DIP) joint injection in horses. DESIGN: Prospective, uncontrolled study. ANIMALS: 10 adult horses. PROCEDURE: 30 minutes before euthanasia, 8 ml of 2% mepivacaine hydrochloride was injected into the dorsal pouch of a forelimb DIP joint. Synovial tissue from the DIP joint and podotrochlear (navicular) bursa and bone tissue from the medullary cavity of the distal sesamoid (navicular) bone were taken from both forelimbs immediately after death. All synovial and bone specimens were analyzed for tissue concentration of mepivacaine by high-performance liquid chromatography. Synovial tissue and bone specimen concentrations from the injected forelimb were compared with corresponding specimens from the noninjected forelimb. All synovial tissue and bone specimen concentrations were compared with an estimated effective tissue concentration of mepivacaine (0.3 microgram/mg) for local anesthesia. RESULTS: Specimen concentrations of mepivacaine from the injected forelimb were significantly greater (P < 0.05) than those in the corresponding tissues of the contralateral noninjected forelimb. All DIP joint and navicular bursa synovial tissue specimens from the injected forelimb had greater than the estimated effective tissue concentration of mepivacaine for local anesthesia. Of the 10 navicular bone specimens from the injected forelimb, 4 were higher and 2 were within 20% of the estimated effective tissue concentration of mepivacaine for local anesthesia. CONCLUSIONS: Mepivacaine hydrochloride deposited into the DIP joint should anesthetize pain arising from navicular bursa synovia and may decrease pain arising from the medullary cavity of the navicular bone. CLINICAL RELEVANCE: DIP joint injection of mepivacaine hydrochloride is not specific for DIP joint pain. 相似文献
3.
An upcoming exchange of a machine tool spindle involves a downtime of several days for a cutting machine. This paper presents
an innovative counter spindle module which can be replaced in significantly less time. The counter spindle module is developed
in a methodical design process and is based on an effective high-precision alignment system, whose functionality and features
are described in detail. Furthermore, an appropriate measuring process to identify the present deviation of a main or counter
spindle is introduced. Finally, the operational capability and efficiency of the developed spindle alignment system is validated
on the basis of the introduced measuring process. 相似文献
4.
Abstract: In recent years, an increasing amount of research in Artificial Intelligence has focused on the representation and manipulation of uncertainty in expert systems. New approaches have been developed and justified because of their mathematical rigor or simplicity, cautiousness, programmability, and/or ability to capture the essence of natural language. Little attention has been paid to the psychological validity of any approach, new or old. To explore the psychological validity of rules that combine uncertainties, Oak Ridge National Laboratory (ORNL) has developed a computer program known as LES. Four applications of LES revealed that subjects' natural combining rules are (1) not best modeled by any generally accepted uncertainty approach and (2) may be highly idiosyncratic. Knowledge Engineers should be aware that cognitive representations of knowledge in expert systems are not routinely being matched with combining rules actually used by experts. Frustrating development activities and highly unsatisfactory expert system performance may result. 相似文献
5.
R Carrizo ME Sosa LS Favier F Penna E Guerreiro OS Giordano CE Tonn 《Canadian Metallurgical Quarterly》1998,61(10):1209-1211
Growth-inhibitory activities of selected natural benzofurans (4-9), trans-cinnamic acid derivatives (10-13), chromene compounds (14 and 16), and some semisynthetic derivatives were determined in last instar larvae of Tenebrio molitor via topical administration in Me2CO. The most inhibitory of the tested compounds were 3-gamma, gamma-dimethylallyl-p-coumaric acid (10) and the benzofuran derivative 12-(p-cumaroyloxy)-tremetone (5), the former compound acting on the pupae and the latter on the last instar larvae. Several developmental deficiencies were observed, and some structure-activity relationships are discussed. 相似文献
6.
Microstructure strongly influences the mechanical properties of cast iron. By inoculating the melt with proper inoculants, foreign substrates are brought into the melt and eventually the graphite can crystallize on them. The elements and substrates that really play a role for nucleation are yet unknown. Until now there is very little knowledge about the fundamentals of nucleation, such as composition and morphology of nuclei. In this work we utilized EN-GJL-200 as a base material and examined several produced specimens. The specimens were cast with and without inoculants and quenched at different solidification states. Specimens were also examined with a high and low oxygen concentration, but the results showed that different oxygen contents have no influence on the nucleation in cast iron melts. Our research was focused on the microscopic examination and phase-field simulations. For studying the samples we applied different analytical methods, where SEM-EDS, -WDS were proved to be most effective. The simulations were conducted by using the software MICRESS, which is based on a multiphase-field model and has been coupled directly to the TCFE3 thermodynamic database from TCAB. On the basis of the experimental investigations a nucleation mechanism is proposed, which claims MnS precipitates as the preferred site for graphite nucleation. This theory is supported by the results of the phase-field simulations. 相似文献
7.
Shafiq Murad Susanne Michen Alexander Becker Monika Füssel Gabriele Schackert Torsten Tonn Frank Momburg Achim Temme 《International journal of molecular sciences》2022,23(10)
In glioblastoma, non-classical human leucocyte antigen E (HLA-E) and HLA-G are frequently overexpressed. HLA-E loaded with peptides derived from HLA class I and from HLA-G contributes to inhibition of natural killer (NK) cells with expression of the inhibitory receptor CD94/NKG2A. We investigated whether NK cells expressing the activating CD94/NKG2C receptor counterpart were able to exert anti-glioma effects. NKG2C+ subsets were preferentially expanded by a feeder cell line engineered to express an artificial disulfide-stabilized trimeric HLA-E ligand (HLA-E*spG). NK cells expanded by a feeder cell line, which facilitates outgrowth of conventional NKG2A+, and fresh NK cells, were included for comparison. Expansion via the HLA-E*spG feeder cells selectively increased the fraction of NKG2C+ NK cells, which displayed a higher frequency of KIR2DL2/L3/S2 and CD16 when compared to expanded NKG2A+ NK cells. NKG2C+ NK cells exhibited increased cytotoxicity against K562 and KIR:HLA-matched and -mismatched primary glioblastoma multiforme (GBM) cells when compared to NKG2A+ NK cells and corresponding fresh NK cells. Cytotoxic responses of NKG2C+ NK cells were even more pronounced when utilizing target cells engineered with HLA-E*spG. These findings support the notion that NKG2C+ NK cells have potential therapeutic value for treating gliomas. 相似文献
8.
Abstract: Knowledge engineers often find that experts' estimates of uncertainty change from one day to the next and therefore often seem unreliable. This article explores the unreliability of probability estimates. Forty undergraduates answered 31 questions concerning the probability of daily events at two separate times. Three answer modalities were available: probability, chances and percent of the time. This paper finds that reliability decreases when answer modalities change from one time to the next. It is hypothesized that problem-solving approaches changed along with the modalities. The subjects represented a wide range in reliability, with the most reliable subjects changing answer modalities less than the unreliable subjects. These results suggest that knowledge engineers should endeavor to have experts express their uncertainty estimates using consistent modalities. 相似文献
9.
GH Vince H Bouterfa R Goldbrunner K Roosen JC Tonn 《Canadian Metallurgical Quarterly》1997,233(2-3):148-150
The azo-dye, Fast Blue (FB), initially employed for retrograde neuronal tracing is increasingly used in cell invasion and migration studies to detect living cells in monolayer and glioma tumor cell spheroid models. As yet, it is assumed that a cell stained with a tracker dye retains the characteristics of the original cell. The following experiments compared the adhesion, migration and proliferation properties of the cell lines U373 and GaMG with and without FB staining. FB staining reduced cell adhesion (P < 0.01) and proliferative activity (P < 0.01) and also had a significant inhibitory effect on cell migration (P < 0.001). From the results presented it follows that FB staining markedly influences basic cell characteristics. 相似文献
10.
We examined the ability of engineered rock structures to enhance the productive capacity of benthic macroinvertebrates 2 years after their installation in a constructed stream in the Northwest Territories, Canada. We used a control‐impact design to compare biological attributes of the structures to those of riffles in natural reference streams and among individual structures. The biomass of epilithon and coarse particulate organic matter, cover by bryophytes and macrophytes and volume of woody debris, however, were similar at structures and unenhanced control sites in the constructed stream and lower than at riffles in reference streams. Total macroinvertebrate density and densities of Chironomidae, Nematoda and Oligochaeta did not differ among engineered structures, unenhanced sites and reference riffles. In contrast, reference streams supported higher densities of Simuliidae and Ephemeroptera compared with engineered structures and unenhanced sites within the channel. Total biomass, biomass of Chironomidae, non‐chironomid Diptera and combined biomasses of (i) Nematoda, Oligochaeta and Turbellaria and (ii) Ephemeroptera, Plecoptera and Hemiptera from reference riffles exceeded those at engineered structures. Density and biomass of macroinvertebrates varied within and among structure types and were highest at one of two ramps, one of two vanes and at the single groin compared with other structures. In the majority of cases, density and biomass of macroinvertebrates from individual structures were less than those at reference streams. These results suggest that engineered structures had variable effects on the productive capacity of benthic macroinvertebrates of the constructed streams and may be related to the extent that structures provided habitat conditions characteristic of reference riffles. © Her Majesty the Queen in Right of Canada 2011. Reproduced with the permission of the Minister of Natural Resources. 相似文献