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991.
We describe the anticipated performance of an x-ray microcalorimeter instrument on ITER. As part of the core imaging x-ray spectrometer, the instrument will augment the imaging crystal spectrometers by providing a survey of the concentration of heavy ion plasma impurities in the core and possibly ion temperature values from the emission lines of different elemental ions located at various radial positions.  相似文献   
992.
We present a nonlinear unmixing approach for extracting the ballistocardiogram (BCG) from EEG recorded in an MR scanner during simultaneous acquisition of functional MRI (fMRI). First, an overcomplete basis is identified in the EEG based on a custom multipath EEG electrode cap. Next, the overcomplete basis is used to infer non-Kirchhoffian latent variables that are not consistent with a conservative electric field. Neural activity is strictly Kirchhoffian while the BCG artifact is not, and the representation can hence be used to remove the artifacts from the data in a way that does not attenuate the neural signals needed for optimal single-trial classification performance. We compare our method to more standard methods for BCG removal, namely independent component analysis and optimal basis sets, by looking at single-trial classification performance for an auditory oddball experiment. We show that our overcomplete representation method for removing BCG artifacts results in better single-trial classification performance compared to the conventional approaches, indicating that the derived neural activity in this representation retains the complex information in the trial-to-trial variability.  相似文献   
993.
将纤维和纺织材料应用到受损膝关节韧带的修复治疗中已经有30多年了。如今,这个领域中最新的研究工作是利用纤维支架材料在根本上使受损组织重新生长。  相似文献   
994.
Because different psychopathologic components of depressive symptoms may have distinct etiologies, examining their differential effects on smoking cessation may elucidate mechanisms underlying the smoking-depression relationship. Negative affect (NA), somatic features (SF), low positive affect/anhedonia (PA), and interpersonal disturbance (IP) have been identified as unique dimensions of depression that can be measured using the Center for Epidemiologic Studies Depression Scale (CESD). This study examined common and unique associations between CESD subscales and baseline smoking characteristics, nicotine withdrawal, and relapse in 157 participants enrolled in a smoking cessation trial for heavy social drinkers. Each dimension was univariately associated with negative and positive reinforcement smoking motives. Only SF had unique relations with tolerance smoking motives and univariate associations with nicotine dependence severity. Only PA predicted cessation-related changes in withdrawal symptoms on quit day. Analyses predicting abstinence at 8, 16, and 26 weeks post quit date showed that NA, SF, and PA each univariately predicted relapse, ps< or =.0083. Only low PA predicted poorer outcomes incrementally to the other dimensions, even when controlling for level of nicotine dependence, smoking frequency, and history of major depression, p = .0018. Interventions targeting anhedonia and low positive affect may be useful for smokers trying to quit.  相似文献   
995.
The objective of this study was to determine the prevalence of antibiotic-resistant bacteria in various herbal products. Twenty-nine herbal supplements (18 traditional and 11 organic products) were purchased from stores and analyzed microbiologically. Total bacterial counts were determined by pour plate and surface spreading on tryptic soy agar (TSA). Antibiotic-resistant bacteria were enumerated on TSA supplemented with ceftriaxone (64 microg/ml) or tetracycline (16 microg/ml). Total bacterial counts ranged from <5 to 2.9 x 10(5) CFU/g. Ceftriaxone- and tetracycline-resistant bacteria were detected in ground garlic samples at 1.1 x 10(2) CFU/g and 3.0 x 102 CFU/g, respectively. Traditional and organic onion powder samples contained tetracycline-resistant bacteria at 17 and 28 CFU/g and ceftriaxone-resistant bacteria at 35 and 2.0 x 10(3) CFU/g, respectively. Other products such as ginger, rosemary, mustard, and goldenseal contained low levels of resistant bacteria. Fifty-two isolates were further evaluated against nine antibiotics, and the prevalence of antibiotic resistance was in the following order: ampicillin, nalidixic acid, trimethoprim, ceftriaxone, and streptomycin. Resistant bacteria were identified as Bacillus spp., Erwinia spp., and Ewingella americana. Staphylococcus spp., Enterobacter cloacae, and Stenotrophomonas maltophilia also were isolated. The presence of antibiotic-resistant bacteria and pathogens in these herbal products suggests that production and use of these products may need further evaluation.  相似文献   
996.
Among the few eukaryotes adapted to the extreme conditions prevailing in acid mine drainage, Euglenae are ubiquitous in these metal(loid)-impacted environments, where they can be exposed to As(III) concentrations up to a few hundreds of mg x L(-1). In order to evaluate their resistance to this toxic metalloid and to identify associated detoxification mechanisms, we investigated arsenic coordination in the model photosynthetic protozoan, Euglena gracilis, cultured at pH 3.2 and exposed to As(III) at concentrations ranging from 10 to 500 mg x L(-1). E. gracilis is shown to tolerate As(III) concentrations up to 200 mg * L(-1), without accumulating this metalloid. X-ray absorption spectroscopy at the As K-edge shows that, in the cells, arsenic mainly binds to sulfur ligands, likely in the form of arsenic-trisglutathione (As-(GS)3) or arsenic-phytochelatin (As-PC) complexes, and to a much lesser extent to carbon ligands, presumably in the form of methylated As(III)-compounds. The key role of the glutathione pathway in As(III) detoxification is confirmed by the lower growth rate of E. gracilis cultures exposed to arsenic, in the presence of buthionine sulfoximine, an inhibitor of glutathione synthesis. This study provides the first investigation at the molecular scale of intracellular arsenic speciation in E. gracilis and thus contributes to the understanding of arsenic detoxification mechanisms in a eukaryotic microorganism under extreme acid mine drainage conditions.  相似文献   
997.
998.
The objective of this research was to investigate the acceptability of muscadine grape (Vitis rotundifolia) genotypes (cultivars and selections) and to correlate overall liking to other quality measurements to determine the main drivers of liking. Twenty‐two genotypes grown at the Univ. of Georgia–Tifton Campus were evaluated. Four retail commercial grape genotypes (Vitis vinifera and “Concord”) were also evaluated for comparison. Panelists familiar with muscadine grapes used the hedonic general labeled magnitude scale (HgLMS, –100 = strongest disliking of any kind ever experienced, +100 = strongest liking of any kind ever experienced) to rate overall liking and the liking of appearance, flavor, pulp texture, and skin texture. Puncture testing was done to assess grape berry texture, and compositional attributes soluble solids and pH were also measured. The sensory results indicated that the grapes were variable with overall liking scores from 12.2 to 39.6. The factors highly correlated with overall liking scores were muscadine flavor, pulp and skin liking, while a significant negative correlation was found between skin liking and skin texture and mechanical texture measures. The muscadine grapes with the highest overall liking scores were Ga. 5‐1‐34 and Ga. 2‐8‐21. Principal component analysis confirmed that grapes with a thinner skin and a higher pH tended to group around overall liking and flavor points. These results indicate that even among panelists familiar with muscadine grapes, skin thickness is a negative characteristic. Breeding for thinner skins may be a positive step in muscadines gaining a more widespread appeal in the fresh fruit market.  相似文献   
999.
The Hughes Borehole is located in the bituminous coal region of south-central Pennsylvania and drains an underground mine complex of ca. 2,950 ha. The borehole discharge averages approximately 63 L/s of acidic (pH 4, 230 mg/L acidity) mine drainage that contains elevated concentrations of Fe(II) (100 mg/L). Long-term monitoring of the site showed that biological Fe(II) oxidation occurred without human intervention and, over previous decades, has produced a 0.6 ha iron mound up to 2 m deep. On-mound channel reactors along with laboratory-scale gutter reactors were constructed to determine conditions that can exploit biological Fe(II) oxidation for passive treatment. Dissolved Fe(II) was much more efficiently oxidized from gutter reactors that contained iron mound sediment than ones without any sediment. Close to 100% of the dissolved influent Fe(II) was oxidized in 5–10 h and 75% of the total dissolved Fe was removed. In addition, the reactors performed better as the sediment aged, so that shorter residence times of 1–2 h were also capable of oxidizing substantial amounts of the influent Fe(II). The addition of surface area to the on-mound reactors improved Fe(II) oxidation at residence times of 30 min or less. The results of this study can be used to help design and build treatment systems for low-pH acid mine drainage (AMD) discharges.  相似文献   
1000.
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