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41.
Characterisation of the optical properties of the internal structures of tomatoes enhances assessment of the composite appearance. Reflectance colorimetry and the Kubelka-Munk analysis to distinguish three distinct maturity groups of tomatoes were tested. Differences in the scatter, absorption and internal transmittance were found amongst the component structures of the intact tomato. Tomato fruit was also pulped and a range of dilutions prepared. The decrease in scatter, absorption and increase in internal transmittance with increased dilution suggests the importance of optical properties with changes in concentration.  相似文献   
42.
前两天我购买了一套索尼家庭影院DTX-S2000,觉得实在物超所值,说出来与大家分享。那天本来是想买一套传统落地式音箱的家庭影院,可看来看去感觉好象什么也没看到,都是清一色的四四方方,或高或矮  相似文献   
43.
We show two-photon spectra and lifetimes acquired using conventional confocal microscopes equipped with an ultra-short pulsed laser and a time-gated intensified charge coupled device. We report on the two-photon spectra and lifetimes of Alexa350, enhanced green fluorescent protein (EGFP), EGFP-CD46, and Cy3 labelled antibodies. Cellular and extracellular EGFP two-photon spectra and lifetimes are compared.  相似文献   
44.
Peritraumatic dissociation (PD) and experiential avoidance (EA) have been implicated in the etiology of posttraumatic stress symptomatology (PTSS); however, the function of these two factors in the onset and maintenance of PTSS following a potentially traumatic event is unclear. The temporal relationships between EA, PD, and the four clusters of PTSS proposed by the Simms/Watson dysphoria model (Simms, Watson, & Doebbeling, 2002) were examined in a three-wave prospective investigation of 532 undergraduate women participating in an ongoing longitudinal study at the time of a campus shooting. Path analyses indicated that preshooting EA predicted greater PD, intrusions, and dysphoria symptoms approximately one month postshooting. PD was associated with increased symptomatology across all four clusters 1-month postshooting, while 1-month postshooting EA was associated with higher dysphoria and hyperarousal symptoms eight months postshooting. PD had a significant indirect effect on all four PTSS clusters eight months postshooting via 1-month postshooting symptom reports. The results suggest that both EA and PD show unique influences as risk factors for PTSS following a potentially traumatic event. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
45.
We estimated the amount of oil remaining in Prince William Sound, Alaska, 12 yr after the 1989 Exxon Valdez spill to assess its importance as a long-term reservoir of toxic hydrocarbons. We found oil on 78 of 91 beaches randomly selected according to their oiling history. Surface oiling was recorded for randomly placed quadrats, which were then excavated and examined for subsurface oil. The cumulative area of beach contaminated by surface or subsurface oil was estimated at 11.3 ha. Surface oil varied little with tide height, but subsurface oil was more prevalent at the middle tide heights. The mass of remaining subsurface oil is conservatively estimated at 55 600 kg. Analysis of terpanes indicated that over 90% of the surface oil and all of the subsurface oil was from the Exxon Valdez and that Monterey Formation oil deposited after the 1964 Alaska earthquake accounted for the remaining surface oil. These results indicate that oil from the Exxon Valdez remains by far the largest reservoir of biologically available polycyclic aromatic hydrocarbons on beaches impacted by the spill and that biota dependent on these beaches risk continued exposure.  相似文献   
46.
Ba(Ti1−xy Sn x Ge y )O3 (BTSG-x-y; x = 0, 0.05; y = 0–0.05) powders were synthesized by a sol-gel (SG) method and for comparative purposes also by a mixed-oxide (MO) method. In this system, BaGeO3 functions as sintering additive. Due to smaller particle sizes of the SG powders a higher sintering activity was found, which resulted in reduced grain growth and in a more homogenous grain size distribution for the corresponding ceramics. The dependence on the paraelectric ⇆ ferroelectric phase transition, i.e. the phase transition temperature, the width of the transition region and completeness were examined by dielectric measurements, DTA as well as by SEM, EDX and XRD investigations with respect to the BaGeO3 content, synthesis method and sintering temperature. The phase transition temperatures of the SG ceramics are remarkably higher than those of the MO ceramics with the same nominal compositions. The reason is a lower tin concentration within the grains of SG ceramics as confirmed by EDX and XRD investigations. The presence of BaGeO3 in barium titanate–stannate system on the basis of a SG method caused an improved incorporation of tin in the BaTiO3 lattice.  相似文献   
47.
Osteoarthritis, the most common joint disorder, is characterised by deterioration of the articular cartilage. Many studies have identified potential therapeutic targets, yet no effective treatment has been determined. The aim of this study was to identify and rank osteoarthritis-associated genes and micro-RNAs to prioritise those most integral to the disease. A systematic meta-analysis of differentially expressed mRNA and micro-RNAs in human osteoarthritic cartilage was conducted. Ingenuity pathway analysis identified cellular senescence as an enriched pathway, confirmed by a significant overlap (p < 0.01) with cellular senescence drivers (CellAge Database). A co-expression network was built using genes from the meta-analysis as seed nodes and combined with micro-RNA targets and SNP datasets to construct a multi-source information network. This accumulated and connected 1689 genes which were ranked based on node and edge aggregated scores. These bioinformatic analyses were confirmed at the protein level by mass spectrometry of the different zones of human osteoarthritic cartilage (superficial, middle, and deep) compared to normal controls. This analysis, and subsequent experimental confirmation, revealed five novel osteoarthritis-associated proteins (PPIB, ASS1, LHDB, TPI1, and ARPC4-TTLL3). Focusing future studies on these novel targets may lead to new therapies for osteoarthritis.  相似文献   
48.
B6O-based materials are known as some of the hardest materials after diamond and cubic boron nitride with a hardness of 45 GPa measured on single crystals. Several attempts were made to produce B6O materials by hot pressing, but without success. Based on thermodynamic considerations the possibility of the use of sintering additives was discussed and the developed concepts were validated by densification of the materials using FAST (field assisted sintering technique)/SPS methods and analysing the microstructure and properties of the resulting materials. Two groups of materials were found to be suitable for the densification: transition metals which form borides with B6O, the elements of the first to fourth main groups of the periodic table and the rare earths (Sc, Y, and lanthanides) which are in equilibrium in the oxide form with B6O and form a liquid phase during densification at 1700–1900 °C. Superhard dense B6O materials were produced and their properties investigated.  相似文献   
49.
The objective of the study was to compare the clinical efficacy of 3 surgical approaches in the treatment of deep recession type defects. Fifty-four (54) gingival recessions > or = 5 mm were randomly assigned to 1 of the 3 treatment groups by blocking the prognostic variables. The first group was treated with a guided tissue regeneration (GTR) procedure using a bioabsorbable membrane, the second with non-resorbable membrane, and the third with a mucogingival surgical approach consisting of a connective tissue graft combined with a coronally advanced flap (bilaminar technique). No differences, in terms of baseline oral hygiene and defect characteristics, were observed among the 3 groups showing an effective blocking approach. The 1-year results indicated that 1) all treatment approaches resulted in clinically significant root coverage and attachment gain; 2) a statistically significant treatment effect (P = 0.012, ANOVA) was observed comparing the bioabsorbable (4.9+/-0.3 mm), the non-resorbable (4.5+/-0.8 mm), and the bilaminar (5.3+/-0.7 mm) groups, in terms of root coverage; 3) the difference in terms of root coverage between the bilaminar and the non-resorbable membrane groups was statistically significant while differences between the 2 GTR groups or between the bilaminar and the bioabsorbable membrane groups did not reach statistical value; 4) the 95% confidence intervals for the proportions of complete successes showed a similar pattern; 5) no statistical difference was demonstrated in the amount of attachment gain among the 3 groups (P=0.73, ANOVA). A regression model showed that the amount of root coverage was significantly affected by the initial recession depth, the procedure and smoking habits: a poorer root coverage result is expected in case of shallow recession type defects, when either bioabsorbable (P < 0.05) or non-resorbable (P < 0.001) membranes are used instead of a bilaminar technique and if the patient smokes (P < 0.01). It was concluded that the mucogingival bilaminar technique is at least as effective as GTR procedures in the treatment of gingival recession > or = 4 mm and thus recession depth is not the parameter which influences the selection of the surgical procedure.  相似文献   
50.
11月10日,力拓集团在上海公布最新的钻石营销计划。借助这个名为“钻动潮流”的项目,四大潮流趋势与公众见面。发布潮流趋势是力拓在华拓展时尚钻饰消费计划的一部分。  相似文献   
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