Low-cost household digesters are a promising appropriate technology which can help reducing the pressure on the environment due to deforestation and greenhouse gases emissions. The biogas and biofertilizer produced can alleviate poverty, by improving health conditions, increasing crops productivity and saving working time and burden for women and children. The aim of this study is to evaluate low-cost digesters technical, environmental and socio-economic impacts in rural communities of the Peruvian Andes, where a pilot project was developed during the last 3 years. Although the benefits are restricted by the performance of anaerobic digestion at high altitude, the results show that the digesters improve household living conditions and economy, while reducing environmental impacts. Biogas production covers around 60% of fuel needs for cooking, leading to 50-60% decrease in firewood consumption (i.e. deforestation) and greenhouse gases emissions; the annual income is increased by 3-5.5% due to fertilizer savings and potato sales. These values could be improved by enhancing digesters performance and the sustainability of the technology. 相似文献
In this paper, we present a new mathematical method that synthesizes normal data sets for quantification of regional myocardium perfusion. In clinical practice, regional myocardial perfusion is often measured with a gamma camera and quantified via circumferential profile analysis. Normal reference profile data is used to increase the accuracy of the clinical interpretations. Our goal is to create reference data from an existing set of archived studies. An iterative mathematical method, based on two statistical hypotheses, was used to generate the study set instead of collecting normal examinations from a healthy population. Clinical validation is based on interpretations by six independent observers. Results of evaluation with synthesized normal data and its validation are presented. 相似文献
A method to control activation of a DNA nanodevice by supplying a complementary DNA (cDNA) strand from an electro‐responsive nanoplatform is reported. To develop functional nanoplatform, hexalayer nanofilm is precisely designed by layer‐by‐layer assembly technique based on electrostatic interaction with four kinds of materials: Hydrolyzed poly(β‐amino ester) can help cDNA release from the film. A cDNA is used as a key building block to activate DNA nanodevice. Reduced graphene oxides (rGOs) and the conductive polymer provide conductivity. In particular, rGOs efficiently incorporate a cDNA in the film via several interactions and act as a barrier. Depending on the types of applied electronic stimuli (reductive and oxidative potentials), a cDNA released from the electrode can quantitatively control the activation of DNA nanodevice. From this report, a new system is successfully demonstrated to precisely control DNA release on demand. By applying more advanced form of DNA‐based nanodevices into multilayer system, the electro‐responsive nanoplatform will expand the availability of DNA nanotechnology allowing its improved application in areas such as diagnosis, biosensing, bioimaging, and drug delivery. 相似文献
We present a non-covalent compatibilization approach to prepare polypropylene (PP) composites containing expanded graphite (EG) and graphene nanoplatelets (GNPs) by melt compounding. This method involves PP matrix functionalization with pyridine (Py) moieties, which are capable of engaging in π-π interactions with the surface of the EG and GNPs. The addition of 10 wt% of PP grafted with amino-pyridine (PP-g-Py) to neat PP facilitated the break-up of EG particles, by intercalating between their layers and facilitating their separation into smaller tactoids. GNPs were prepared starting from EG through a thermomechanical exfoliation method. Addition of GNPs to PP resulted in well-dispersed platelets having aspect ratios as high as 40, whereas in the presence of the PP-g-Py compatibilizer the matrix contained sub-micron scale platelets. The electrical percolation thresholds were in the vicinity of 6 and 10 vol% in the compatibilized PP-EG and PP-GNP composites, respectively, and the maximum value of the electrical conductivity achieved was 10−1 S/m for the compatibilized GNP composites. Addition of GNPs resulted in increases in the flexural moduli by as much as 95% compared to the unfilled PP, whereas the impact strength remained unaffected up to 10 wt% GNP content. 相似文献
Punica granatum L. (pomegranate) fruit is known to be an important source of bioactive phenolic compounds belonging to hydrolysable tannins. Pomegranate extracts have shown antifungal activity, but the compounds responsible for this activity and their mechanism/s of action have not been completely elucidated up to now. The aim of the present study was the investigation of the inhibition ability of a selection of pomegranate phenolic compounds (i.e., punicalagin, punicalin, ellagic acid, gallic acid) on both plant and human fungal pathogens. In addition, the biological target of punicalagin was identified here for the first time. The antifungal activity of pomegranate phenolics was evaluated by means of Agar Disk Diffusion Assay and minimum inhibitory concentration (MIC) evaluation. A chemoinformatic analysis predicted for the first time topoisomerases I and II as potential biological targets of punicalagin, and this prediction was confirmed by in vitro inhibition assays. Concerning phytopathogens, all the tested compounds were effective, often similarly to the fungicide imazalil at the label dose. Particularly, punicalagin showed the lowest MIC for Alternaria alternata and Botrytis cinerea, whereas punicalin was the most active compound in terms of growth control extent. As for human pathogens, punicalagin was the most active compound among the tested ones against Candida albicans reference strains, as well as against the clinically isolates. UHPLC coupled with HRMS indicated that C. albicans, similarly to the phytopathogen Coniella granati, is able to hydrolyze both punicalagin and punicalin as a response to the fungal attack. Punicalagin showed a strong inhibitory activity, with IC50 values of 9.0 and 4.6 µM against C. albicans topoisomerases I and II, respectively. Altogether, the results provide evidence that punicalagin is a valuable candidate to be further exploited as an antifungal agent in particular against human fungal infections. 相似文献
The Polish Patent Office activity within the scope of its patent information policy—with emphasis on the changes since the 1990s—is described. In addition to aspects of patent searching, such as documentation and databases, dissemination activities, for example education and training, and the role of Patent Information Centres, is covered. New challenges associated with the promotion of intellectual property protection and its role for the economy are also highlighted. 相似文献
This paper reports results on the sensitivity of straight polymer-clad silica (PCS) detection fibers with short sensing parts coated with polysiloxane polymers to toluene dissolved in water. The detection was based on refractive index changes of the polymers induced by the penetration of toluene into them. These changes were detected by measuring changes of the output power from the detection fibers excited by an inclined collimated beam at 630 nm.
Commercially available Cablelite 950-701 and two types of polymethylphenylsiloxane polymers developed at the Romanian Academy were tested as materials for the fabrication of the detection part in the fiber cladding. These parts were prepared by application of polymer layers onto a bare silica core by a dip-coating technique. Layers with thicknesses of about 20 μm were prepared.
Examples of angular distributions of the output power determined for the detection polymers in contact with air, time response curves measured with the detection parts brought into contact with aqueous solutions of toluene under different hydrodynamic conditions, and sensitivity curves are shown in the paper. The best detection limit of about 10 mg/l of toluene, reversibility and linearity of the fiber response in a range 0–100 mg/l could be achieved with fibers coated with Cablelite 950-701 polymer. 相似文献