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1.
Numerous investigations have been carried out on the spectral distribution of the light of different species of fireflies. Here we record the emission spectrum of the Indian species of the firefly Luciola praeusta Kiesenwetter 1874 (Coleoptera : Lampyridae : Luciolinae) on a color film. Green and red color-sectors, with an intense yellow one in between, appear in this spectrum. Intensity profile of this spectrum reveals a hitherto undetected strong narrow yellow line, which lies within the full-width-at-half maximum (FWHM) of the intensity profile. The spectrum recorded in a high-resolution spectrometer confirms the presence of this sharp intense line. This finding lends support to an earlier drawn analogy between the in vivo emission of the firefly and laser light. 相似文献
2.
European Union (EU) Member States have agreed to limit their greenhouse gas (GHG) emissions from sectors not covered by the EU Emissions Trading Scheme, including emissions from agricultural sector. The aggregated GHG emission rate (i.e. t CO2 eq. from agricultural sector per country) is commonly used to measure the overall size of agriculture’s influence on climate. And indeed, since 2005, EU has managed to decrease its aggregated GHG emissions by 3.1%. However, the question is—does that mean that EU’s agriculture has become less emission intensive? This paper answers the question by providing a different perspective for the assessment and comparison of the agricultural GHG emissions in 28 EU Member States. It is done by applying three different approaches, including creation of derived indicators and application of multi-criteria analysis (TOPSIS), which is a novel approach for comparison of agricultural GHG emission mitigation performance. The results show that each EU Member State performs very differently in emission intensities. Even more, the emission intensity results show an alarming tendency of increase in most of the EU Member States, which indicates that the measured changes in aggregate agricultural GHG emission rates are misleading. Therefore, the paper suggests reconsidering the policy targets for GHG emission limits. 相似文献
3.
《Bioorganic & medicinal chemistry》2016,24(9):2043-2052
3-[18F]Fluoro-2-hydroxypropyl substituted compounds were synthesized and evaluated as novel 18F-labeled PET tracers for imaging Aβ plaque in a living brain. All compounds exhibited high binding affinities toward the synthetic Aβ1–42 aggregate and/or Alzheimer’s disease brain homogenate. In the microPET study with normal mice, the 3-[18F]fluoro-2-hydroxypropyl substituted compounds resulted in fast brain washout by reducing the lipophilicities of the compounds. Intriguingly, (S)-configured PET tracers, (S)-[18F]1b and (S)-[18F]1c, exhibited a 2.8 and 4.0-fold faster brain washout rate at a peak/30 min in the mouse brain than the corresponding (R)-configured PET tracers despite there being no meaningful difference in binding affinities toward Aβ plaque. A further evaluation of (S)-[18F]1c with healthy rhesus monkeys also revealed excellent clearance from the frontal cortex with ratios of 7.0, 16.0, 30.0 and 49.0 at a peak/30, 60, 90, and 120 min, respectively. These results suggest that (S)-[18F]1c may be a potential PET tracer for imaging Aβ plaque in a living brain. 相似文献
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In order to investigate the reliability of the Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) for trace
element analysis of biological materials, we have carried out extensive investigations on human plasma, using an Applied Research
Laboratory’s ICP-AES. When we aspirated the untreated plasma into the spectrometer, we obtained unreliable and nonreproducible
results. However, when we pretreated the plasma by wet digestion (to destroy all the organic material), we achieved reproducible
and consistent results. It is, therefore, suggested that biological samples should be pretreated, preferably by wet digestion,
before being aspirated into the ICP-AES for analysis. 相似文献
7.
Yuichi Moriguchi Atsushi Terazono 《The International Journal of Life Cycle Assessment》2000,5(5):281-286
We developed a simplified emission dispersion and exposure-assessment model designed to reflect the site-specific health impacts
of air pollution in life-cycle impact assessment (LCIA). We proposed an EXposure Per Emission Coefficient (EXPEC), a dimensionless
parameter representing the relative amount of pollutant inhaled per emission. EXPEC values were calculated for two typical
source categories - electric power plants and road vehicles — on a concentric circle model. The EXPEC values were significantly
different for different locations and source categories. We examined the application of EXPEC in a case study that compared
the effects of emissions from electric and gasoline-engine vehicles. EXPEC is a useful tool for assessing spatially differentiated
potential impacts. 相似文献
8.
Due to their exquisite affinity and specificity, antibodies have become extremely promising vectors for the delivery of radioisotopes to cancer cells for PET imaging. However, the necessity of labeling antibodies with radionuclides with long physical half-lives often results in high background radiation dose rates to non-target tissues. In order to circumvent this issue, we have employed a pretargeted PET imaging strategy based on the inverse electron demand Diels-Alder cycloaddition reaction. The methodology decouples the antibody from the radioactivity and thus exploits the positive characteristics of antibodies, while eschewing their pharmacokinetic drawbacks. The system is composed of four steps: (1) the injection of a mAb-trans-cyclooctene (TCO) conjugate; (2) a localization time period during which the antibody accumulates in the tumor and clears from the blood; (3) the injection of the radiolabeled tetrazine; and (4) the in vivo click ligation of the components followed by the clearance of excess radioligand. In the example presented in the work at hand, a 64Cu-NOTA-labeled tetrazine radioligand and a trans-cyclooctene-conjugated humanized antibody (huA33) were successfully used to delineate SW1222 colorectal cancer tumors with high tumor-to-background contrast. Further, the pretargeting methodology produces high quality images at only a fraction of the radiation dose to non-target tissue created by radioimmunoconjugates directly labeled with 64Cu or 89Zr. Ultimately, the modularity of this protocol is one of its greatest assets, as the trans-cyclooctene moiety can be appended to any non-internalizing antibody, and the tetrazine can be attached to a wide variety of radioisotopes. 相似文献
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Structural decomposition analysis (SDA) has been widely used by researchers to study changes in carbon emissions or aggregate emission intensity over time in a country. These studies may be called temporal-SDA analysis. Similarly, SDA analysis can be conducted by studying variations in carbon emissions or aggregate emission intensity between countries or between regions in a country, i.e. a decomposition analysis conducted spatially. In spatial-SDA analysis, the objective is often to understand the contributions of factors such as emission intensity, Leontief structure, and final demand in explaining the difference in total carbon emissions or aggregate emission intensities between two countries or regions. We review the literature of spatial-SDA analysis and propose a spatial-SDA framework for multi-region comparisons. Both the additive and multiplicative SDA forms are presented in the framework. Using the framework, 30 geographical regions in China are compared and ranked based on their emission performance. This proposed framework can also be used to evaluate other performance indicators in multi-region comparisons. 相似文献