182 research outputs found
Does Innovation Facilitate Meeting the CO2 Emission Reduction Targets of China: A Non-Linear Approach
China has been implementing energy efficiency and CO2 emission reduction schemes at the provincial level that have been embedded in the National Five Year Plans of the country. We set out to investigate the relationship between R&D expenditures and CO2 emissions in China at the province level in the context of the planned emissions reduction targets. We explore the possibility of the existence of a non-linear relationship between R&D expenditures and CO2 emissions with a non-parametric methodology, a fixed effect panel data quantile (FEQR) regression estimator applied to a panel of 30 provinces. We stratify the sample according to the five emissions reduction target tiers of the 12th Five-Year National Plan of China and we investigate the role of R&D expenditures in emissions reduction within each of the tiers. We find an inverse U relationship with different turning points for the three middle tiers and a U-shaped relationship for the tier under the most stringent environmental regulation. We find no effect in the tier with the least stringent emissions reduction targets. A further investigation shows that the above results are attributed to sectors with relatively low energy intensity and not to the sectors of heavy industry. The results allow us to draw broad conclusions about the effectiveness of investment in new technologies as a means of meeting the CO2 targets in China
A systematic review on the relations between pasta consumption and cardio-metabolic risk factors
Aims: The traditional Italian dish pasta is major food source of starch with low glycemic index (GI), and also an important low-GI component of the Mediterranean diet. This systematic review aimed at assessing comprehensively and in-depth the potential benefit of pasta on cardio-metabolic disease risk factors.
Data Synthesis: Following a standard protocol, we conducted a systematic literature search of PubMed, CINAHL, and Cochrane Central Register of Controlled Trials, for prospective cohort studies and randomized controlled dietary intervention trials that examined pasta, and pasta-related fiber and grain intake in relation to cardio-metabolic risk factors of interest. Studies evaluating postprandial glucose response to pasta compared to bread or potato were quantitatively summarized using meta-analysis of standardized mean difference. Evidence from studies with pasta as part of low-GI dietary intervention and studies investigating different types of pasta were qualitatively summarized.
Conclusions: Pasta meals have significant lower postprandial glucose response compared to bread or potato meals, but evidence was lacking in terms of how the intake of pasta can influence cardio-metabolic disease risk. More long-term randomized controlled trials are needed where investigators directly contrast the cardio-metabolic effects of pasta and bread or potato. Long-term prospective cohort studies with required data available should also be analyzed regarding the effect of pasta intake on disease endpoints
Toxicological effects of cadmium on deep-sea mussel Gigantidas platifrons revealed by a combined proteomic and metabolomic approach
IntroductionMarine metal contamination caused by deep-sea mining activities has elicited great concern from both social and scientific communities. Among the various metals deep-sea organisms might encounter, cadmium (Cd) is a widely detected metal that in very small amounts is nonetheless capable of severe toxicity. Yet due to both remoteness and technical challenges, insights into the effects of metal exposure resulting from mining activities upon deep-sea organisms are limited.MethodsHere, we investigated Cd’s toxicological effects on deep-sea mussels of Gigantidas platifrons exposed to 100 or 1000 g/L of Cd for 7 days; an integrated approach was used that incorporated proteomics and metabolomics along with traditional approaches (metal concentrations, metal subcellular distribution, and anti-oxidative and immune-related biochemical indexes).Results and DiscussionResults showed that Cd exposure caused significant Cd’s accumulation in mussel gills and redistribution of Cd among subcellular compartments, with cellular debris being the primary binding site. Although anti-oxidative enzymes activities (superoxide dismutase and catalase) were not significantly altered in mussel gills of both exposed groups, the markedly increased level of glutathione S-transferase detected via proteomic technique clearly evinced that deep-sea mussels suffered from oxidative stress under Cd exposure. Besides, altered activities of acid phosphatase and alkaline phosphatase assayed by traditional methods along with the predominant presence of largely altered immune-related proteins detected by proteomic data strongly revealed an immune response of deep-sea mussels elicited by Cd. In addition, results of proteomics combined with those of non-targeted metabolomics demonstrated that Cd could exert toxicity by disrupting cytoskeleton structure, ion homeostasis, and primary metabolisms of energy, lipid, and nucleotide in deep-sea mussels. As demonstrated in this study, proteomics and metabolomics can be used in tandem to provide valuable insights into the molecular mechanisms of deep-sea organisms’ response to Cd exposure and for helping to discover potential biomarkers for application during deep-sea mining assessments
Quadrat soil pollen signal reflects plant important values in forests and shrublands from subtropical China
Pollen analysis, a crucial tool in botany and ecology for examining historical biotic dynamics, has elicited debate owing to its complex link with vegetation. The challenge lies in discerning the ecological significance of pollen data. In this study, we conducted detailed quadrat surveys on Jinhua Mountain, subtropical China, analyzing topsoil pollen to determine whether pollen signals accurately reflect key ecological components in the forests and shrublands. We performed direct comparisons between pollen and plant compositions and calculated pollen percentages and plant Important Values (IVs) for each quadrat. The results indicate greater homogeneity in pollen composition across the study area compared to plant composition, particularly in the high percentage of Pinus pollen. However, distinct plant communities exhibited significantly different pollen compositions, as evidenced by the multi-response permutation test. This divergence aligns with variations in the dominant plant species across different communities. There were significant correlations between pollen percentages and plant IVs, with correlation coefficients of 0.55 (p < 0.001) at the quadrat level and 0.78 (p < 0.001) at the taxon level. These results support the utility of pollen analysis for representing ecologically significant values in subtropical Chinese forests and shrublands. Such correlations might also be extrapolated to pollen-based paleoecological studies
Analysis of energy saving and emission reduction of secondary fiber mill based on data mining
Waste paper recycling is an important way to realize the environmental protection development of the papermaking industry. The quality of the pulp will affect the pulp sales of the secondary fiber paper mills. The waste paper pulp can be adjusted by controlling the pulping process working conditions, but the working conditions of the waste paper pulping process have too many parameters. And the parameters are coupled with each other, it is difficult to control. In order to find the best working conditions and improve the quality of the pulp, this study uses the association rules algorithm to optimize the parameters for the waste paper pulping process. These parameters are power of refiner, waste paper concentration of refiner, the volume of slurry that enters deinked process, deinking agent amount, deinking time, deinking temperature, bleaching agent amount, bleaching time, and bleaching temperature. The test results show that the qualified rate of the pulp produced under the improved working conditions is 92.56%, an increase of 6.93%, and the average electricity consumption per ton of pulp is reduced by 5.76 kWh/t. In addition to potential economic benefits, this method can reduce carbon emissions
Plant sedimentary DNA as a proxy for vegetation reconstruction in eastern and northern Asia
Plant DNA from sediments (sedDNA) are increasingly used to reconstruct the past vegetation composition, which contrasts with the few investigations on the relationship between the plant sedDNA signal and modern vegetation. Here, we applied broad-scale terrestrial plant sedDNA metabarcoding on surface sediments from 201 lakes in eastern and northern Asia to discuss the applicability as well as the limitations of using plant sedDNA metabarcoding for palaeovegetation studies. In total, 381 terrestrial plant taxa were determined with the universal plant primers of trnL g and h. Overall, plant sedDNA approach is able to retrieve major vegetation signals. The composition of plant sedDNA reflect well the vegetation types and related climate characteristics, and it also signals which are the dominant taxa in the vegetation. Our results indicate that plant sedDNA metabarcoding could be a reliable proxy of vegetation composition at a sub-continental scale and along large environmental gradients. But certain drawbacks such as limited taxonomic resolution, biases in the relative abundance of taxa, and a generally high variability of samples from similar vegetation types need to be solved before it can be widely applied to reconstruct palaeofloras
Resolved Raman sideband cooling of a single optically trapped cesium atom
We developed a resolved Raman sideband cooling scheme that can efficiently
prepare a single optically trapped cesium (Cs) atom in its motional ground
states. A two-photon Raman process between two outermost Zeeman sublevels in a
single hyperfine state is applied to reduce the phonon number. Our scheme is
less sensitive to the variation in the magnetic field than the commonly used
scheme where the two outermost Zeeman sublevels belonging to the two separate
ground hyperfine states are taken. Fast optical pumping with less spontaneous
emission guarantees the efficiency of the cooling process. After cooling for 50
ms, 82% of the Cs atoms populate their three-dimensional ground states. Our
scheme improves the long-term stability of Raman sideband cooling in the
presence of magnetic field drift and is thus suitable for cooling other trapped
atoms or ions with abundant magnetic sublevels.Comment: 4 pages, 3 figures, 1 tabl
Coherence time of 20 s with a single cesium atom in an optical dipole trap
We analyze the decoherence between two ground electronic states of an
optically trapped atom by adopting a full description of the atomic
wavefunction. The motional state, i.e., the phonon state, is taken into
account. In addition to the decoherence due to the variance of differential
light shift (DLS), a new decoherence mechanism, phonon-jumping-induced
decoherence (PJID), is discovered and verified experimentally. A coherence time
of s is then obtained for a single Cs atom by suppressing both
variances of DLS and PJID by trapping the atom in a blue-detuned BBT and
preparing the atom into its three-dimensional motional ground states. Our work
opens a new prospect to extend the coherence time of optically trapped single
atoms.Comment: 5 pages, 4 figures in the main text; 6 pages, 8 figures in the
supplementary materia
Application of plant DNA metabarcoding of lake sediments for monitoring vegetation compositions on the Tibetan Plateau
Benefiting from the rapid development of environmental DNA (eDNA) technologies, sedimentary DNA (sedDNA) emerges as a promising tool for monitoring plant compositions in remote regions. The Tibetan Plateau (TP), renowned for its harsh environment and numerous ponds and lakes, presents a potentially demanding region for the application of sedDNA on vegetation investigations. Here, we used the g and h universal primers for the P6 loop region of the chloroplast trnL (UAA) intron to amplify plant DNA in surface sediments from 59 ponds and small lakes on the southwestern TP. The applicability and limitations of using plant DNA metabarcoding for modern vegetation monitoring and palaeo-vegetation reconstructions have been assessed by comparing sedDNA, pollen, and vegetation survey data. Our results showed that plant DNA metabarcoding recorded 186 terrestrial taxa, of which 30.1% can be identified at the species level. The plant sedDNA approach can effectively disclose the dominant plant taxa (including Asteraceae, Cyperaceae and Poaceae) and significant vegetation assemblages in the vicinity of the investigated sites. The number of taxa and taxonomic resolution of plant sedDNA exceeded that of pollen analysis (75 taxa detected, 5.3% can be identified at species level). Unlike pollen that retains a broad spectrum of regional plant signals (including Pinus and Artemisia), plant sedDNA mirrors very local plants, underscoring its utility in local vegetation monitoring and reconstructions. To conclude, plant DNA metabarcoding of (small) lake sediments warrant increased attention in the future for local vegetation monitoring and reconstructions on the TP
Confocal Raman microscopy for assessing effects of preservation methods on symbiotic deep-sea mussel gills
Confocal Raman microscopy (CRM) is a powerful tool for biological research, which can provide information regarding the composition and distribution of biomolecules in an in situ, label-free, non-destructive manner and with high spatial resolution. Sample preservation is often an unavoidable step, especially for symbiotic deep-sea samples. Moreover, protocols for the preservation of samples for CRM have not been established and specific effects of different preservation methods on biomolecules have not been studied for relevant samples. In this study, we used deep-sea mussel Gigantidas platifrons, an ideal model in the study of deep-sea symbiosis and investigated the effect of four common preservation methods on the results of CRM imaging and signals. The methods included snap-freeze (SF), SF followed by rapid fixation in methanol (SF-MeOH), 2.5% glutaraldehyde and 2% paraformaldehyde fixation (SF-GP), and 4% paraformaldehyde and alcohol fixation (PS-PA). The results of this study indicate that SF was the most effective method for the comprehensive analysis of the biomolecular composition although the sectioning success rate was relatively low. Moreover, SF-MeOH was found to be effective when SF is not sufficient in obtaining good morphology in sections, or when the effect of chemical bonding on the composition of biomolecules upon SF-MeOH can be neglected. Finally, SF-GP and PS-PA were found to be the most effective methods considering the overall morphological observation. However, they were less suitable for metabolic studies. We believe our results can provide guidance for further studies of Raman on symbiotic deep-sea biological samples. It is of great importance for the wide application of Raman technique
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