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1.
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.
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.
Married couples with a female agoraphobic spouse (n = 22) were compared with demographically similar community control couples (n = 21) on self-report and observational measures of marital interaction. Consistent with hypotheses, husbands of agoraphobic women were more critical of their wives than were control husbands, and clinical couples were less likely to engage in positive problem solution than control couples. Contrary to hypothesis, clinical husbands were not less supportive than control husbands. Where general measures of marital distress were concerned, clinical couples, relative to control couples, evinced more distress by self-report, by their higher rate of negative nonverbal behavior, and by their longer sequences of negative exchanges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
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   
5.
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   
6.
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   
7.
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   
8.
The preparation of a cup of coffee may vary between countries, cultures and individuals. Here, an analysis of nine different extraction methods is presented regarding analytical and sensory aspects for four espressi and five lunghi. This comprised espresso and lungo from a semi-automatic coffee machine, espresso and lungo from a fully automatic coffee machine, espresso from a single-serve capsule system, mocha made with a percolator, lungo prepared with French Press extraction, filter coffee and lungo extracted with a Bayreuth coffee machine. Analytical measurements included headspace analysis with HS SPME GC/MS, acidity (pH), titratable acidity, content of fatty acids, total solids, refractive indices (expressed in °Brix), caffeine and chlorogenic acids content with HPLC. Sensory analysis included visual, aroma, flavor and textural attributes as well as aftersensation. The technical differences in the extraction methods led to a higher concentration of the respective quantities in the espressi than in the lunghi. Regarding the contents per cup of coffee, the lunghi generally had a higher content than the espressi. The extraction efficiency of the respective compounds was mainly driven by their solubility in water. A higher amount of water, as in the extraction of a lungo, generally led to higher extraction efficiency. Comparing analytical data with sensory profiles, the following positive correlations were found total solids ? texture/body, headspace intensity ? aroma intensity, concentrations of caffeine/chlorogenic acids ? bitterness and astringency.  相似文献   
9.
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   
10.
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   
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