The composition and the distribution of extracellular polymeric substances (EPS) and pellets of autotrophic nitrifying biofilm and activated sludge were investigated in this work. Fourier-transform ...Infrared Spectroscopy, fluorescent in situ hybridization and fluorescence staining were used to examine proteins, carbohydrates, humic substances and DNA being present in the biofilms and the sludge samples. To investigate extraction efficiency and its effect on characterization of tightly bounded EPS, four extraction methods (ethylenediamine tetraacetic acid (EDTA), NaOH, cationic exchange resin (CER), ultrasound) were compared. EDTA and ultrasound showed more effective extraction ability than NaOH and CER. NaOH and ultrasound extraction led to high activity of glucose-6-phosphate dehydrogenase from cell lysis, which was confirmed by fluorescence staining analysis. Ultrasound and NaOH extraction yielded 18% and 11% of dead cells in biofilm, respectively, whereas they obtained 11% and 9% of dead cells in activated sludge, respectively. Four layers of extractible products were separated from autotrophic nitrifiering flocs. The extraction results indicated that extraction yield in different layers varied in a wide range: 3–6% of soluble EPS, 5–10% of loosely bound EPS, 34–67% of tightly bound EPS and 30–60% of pellets.
Variations of the North Atlantic subtropical high (NASH) western ridge and their implication to the Southeastern United States (SE US) summer precipitation were analyzed for the years 1948–2007. The ...results show that the movement of the NASH western ridge regulates both moisture transport and vertical motion over the SE US, especially in the last three decades, during which the ridge moved westward towards the American continent. When the NASH western ridge is located southwest (SW) of its mean climate position, excessive summer precipitation is observed due to an enhanced moisture transport. In contrast, when the western ridge is located in the northwest (NW), a precipitation deficit prevails as downward motion dominates the region. Composite analysis indicates that SW ridging results mainly from the NASH center’s intensification; whereas NW ridging is likely caused by stationary wave propagation from the eastern Pacific/US western coast. In recent decades, both the SW and NW ridge positions have been observed to increase in frequency. Our results suggest that the increase in the SW ridging consistently follows the NASH’s intensification associated with anthropogenic forcing as projected by coupled climate models. However, the increased frequency of NW ridging tends to follow the positive Pacific decadal oscillation (PDO) index. Thus, the enhanced variability in the SE US summer precipitation in recent decades might be a combined result of anthropogenic forcing and internal variability of the climate system. Results suggest that, as anthropogenic forcing continues to increase, the SE US will experience more frequent wet summers and an increase in the frequency of dry summers during positive PDO phases.
This study investigates the changes of the North Atlantic subtropical high (NASH) and its impact on summer precipitation over the southeastern (SE) United States using the 850-hPa geopotential height ...field in the National Centers for Environmental Prediction (NCEP) reanalysis, the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40), long-term rainfall data, and Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) model simulations during the past six decades (1948–2007). The results show that the NASH in the last 30 yr has become more intense, and its western ridge has displaced westward with an enhanced meridional movement compared to the previous 30 yr. When the NASH moved closer to the continental United States in the three most recent decades, the effect of the NASH on the interannual variation of SE U.S. precipitation is enhanced through the ridge’s north–south movement. The study’s attribution analysis suggested that the changes of the NASH are mainly due to anthropogenic warming. In the twenty-first century with an increase of the atmospheric CO₂ concentration, the center of the NASH would be intensified and the western ridge of the NASH would shift farther westward. These changes would increase the likelihood of both strong anomalously wet and dry summers over the SE United States in the future, as suggested by the IPCC AR4 models.
Lung cancer is the most common malignancy and leads to around one-quarter of all cancer deaths. Great advances have been achieved in the treatment of lung cancer with novel anticancer agents and ...improved technology. However, morbidity and mortality rates remain extremely high, calling for an urgent need to develop novel anti-lung cancer agents. 1,2,3-Triazole could be readily interact with diverse enzymes and receptors in organisms through weak interaction. 1,2,3-Triazole can not only be acted as a linker to tether different pharmacophores but also serve as a pharmacophore. This review aims to summarize the recent advances in 1,2,3-triazole-containing compounds with anti-lung cancer potential, and their structure-activity relationship (SAR) together with mechanisms of action is also discussed to pave the way for the further rational development of novel anti-lung cancer candidates.
We have observed that the dry-season length (DSL) has increased over southern Amazonia since 1979, primarily owing to a delay of its ending dates (dry-season end, DSE), and is accompanied by a ...prolonged fire season. A poleward shift of the subtropical jet over South America and an increase of local convective inhibition energy in austral winter (June–August) seem to cause the delay of the DSE in austral spring (September–November). These changes cannot be simply linked to the variability of the tropical Pacific and Atlantic Oceans. Although they show some resemblance to the effects of anthropogenic forcings reported in the literature, we cannot attribute them to this cause because of inadequate representation of these processes in the global climate models that were presented in the Intergovernmental Panel on Climate Change's Fifth Assessment Report. These models significantly underestimate the variability of the DSE and DSL and their controlling processes. Such biases imply that the future change of the DSE and DSL may be underestimated by the climate projections provided by the Intergovernmental Panel on Climate Change's Fifth Assessment Report models. Although it is not clear whether the observed increase of the DSL will continue in the future, were it to continue at half the rate of that observed, the long DSL and fire season that contributed to the 2005 drought would become the new norm by the late 21st century. The large uncertainty shown in this study highlights the need for a focused effort to better understand and simulate these changes over southern Amazonia.
Conversion of agricultural lands to urban uses affects regional and global climate not only through the release of greenhouse gases but also through altering land surface physical processes such as ...energy and water balances. Most existing studies on the meteorological impacts of urbanization focus on urban heat island effects with little attention on its impacts of atmospheric humidity, a key variable in hydrometeorology and climate science. We define the influences of urbanization on reducing atmospheric humidity and elevating vapor pressure deficit as urban dry island (UDI) effects. We conduct a case study in the Yangtze River Delta, a typical humid area in southern China that is under rapid urbanization. We examine spatiotemporal characteristics of UDI and identify potential drivers during 2001–2014. Relationships and interactions between variations of air temperature, atmospheric humidity, evapotranspiration, and leaf area index of different land cover were determined using correlation and attribution analyses at both station and regional levels. We show that atmospheric humidity decreased dramatically and vapor pressure deficit increased sharply in the urban core, resulting in enhanced UDI. In addition to global warming and localized urban heat island, UDI is closely related to the loss of vegetation cover (i.e., natural wetlands and paddies). Reduction of evapotranspiration or latent heat is another important factor contributing to UDI effects. We conclude that the role of vegetated land cover and associated ecohydrological processes in moderating UDI and maintaining a stable climate and environment should be considered in massive urban planning and global change impact assessment in southern China.
Key Points
Proposed urban dry island (UDI) to characterize urbanization effects on reducing atmospheric humidity and elevating vapor pressure deficit
Enhanced UDI effects are explained by feedback of the ecohydrological cycle to urban land cover change
Urban heat island and UDI effects are coupled and should be collectively addressed in urban planning and climate change assessment
Technological innovation is a pivotal driver of high-quality economic development, and China's distinctive fiscal decentralization model stands out as a crucial institutional factor behind the ...country's economic growth miracle. Despite its significant academic and practical implications, there is a noticeable scarcity of literature on examining government fiscal decentralization through the lens of technological innovation. This paper addresses fundamental research questions regarding the relationship between technological innovation and fiscal decentralization. Leveraging balanced panel data from 30 provinces in China spanning 2005 to 2020, our findings indicate that technological innovation positively impacts the fiscal decentralization of local governments. Specifically, for each standard deviation increase in technological innovation, there is a corresponding 0.1508 standard deviation in fiscal decentralization. The mechanism driving this relationship lies in technological innovation's ability to enhance enterprise profit levels, increasing tax and non-tax revenues for local governments. Importantly, when non-tax revenue at the central government level surpasses tax revenue, the resulting augmentation in local government revenue contributes to an elevated level of fiscal decentralization. In conclusion, this paper offers valuable insights into the government's endeavors to promote scientific and technological innovation while enhancing local fiscal decentralization. These insights contribute to an improved quality of economic development.
Atmospheric moisture budget and its regulation of the summer (June–July–August) precipitation over the Southeastern United State (SE U.S.) were examined during 1948–2007 using PRECipitation ...REConstruction over Land and multiple reanalysis datasets. The analysis shows that the interannual variation of SE U.S. summer precipitation can be largely explained by the leading Empirical Orthogonal Function mode showing a spatially homogenous sub-continental scale pattern. Consequently, areal-averaged precipitation was investigated to focus on the large-scale rainfall changes over the SE U.S. The wavelet analysis identifies an increased 2–4 year power spectrum in recent 30 years (1978–2007), suggesting an intensification of the interannual variability. Analysis of the atmospheric moisture budget indicates that the increase in precipitation variability is mainly caused by moisture transport, which exhibits a similar increase in the 2–4 year power spectrum for the same period. Moisture transport, in turn, is largely controlled by the seasonal mean component rather than the subseasonal-scale eddies. Furthermore, our results indicate that dynamic processes (atmospheric circulation) are more important than thermodynamic processes (specific humidity) in regulating the interannual variation of moisture transport. Specifically, the North Atlantic Subtropical High western ridge position is found to be a primary regulator, with the ridge in the northwest (southwest) corresponding to anomalous moisture divergence (convergence) over the SE U.S. Changes in moisture transport consistent with the increased frequency of these two ridge types in recent 30 years favor the intensification of summer precipitation variability.
Myzus persicae is an important pest that has developed resistance to nearly all currently used insecticidal products. The employment of insecticide synergists is one of the effective strategies that ...need to be developed for the management of this resistance. Our study showed that treatment with a combination of the antibiotic, rifampicin, with imidacloprid, cyantraniliprole, or clothianidin significantly increased their toxicities against M. persicae, by 2.72, 3.59, and 2.41 folds, respectively. Rifampicin treatment led to a noteworthy reduction in the activities of multifunctional oxidases (by 32.64%) and esterases (by 23.80%), along with a decrease in the expression of the CYP6CY3 gene (by 58.57%) in M. persicae. It also negatively impacted the fitness of the aphids, including weight, life span, number of offspring, and elongation of developmental duration. In addition, bioassays showed that the combination of rifampicin and a detoxification enzyme inhibitor, piperonyl butoxide, or dsRNA of CYP6CY3 further significantly improved the toxicity of imidacloprid against M. persicae, by 6.19- and 7.55-fold, respectively. The present study suggests that development of active ingredients such as rifampicin as candidate synergists, show promise to overcome metabolic resistance to insecticides in aphids.
•Rifampicin significantly increased toxicityies of imidacloprid, cyantraniliprole, and clothianidin to Myzus persicae.•Fitness, metabolic detoxification enzymes, and the P450 gene CYP6CY3 were related to insecticide toxicity to M. persicae.•Imidacloprid toxicity against M. persicae was improved by combination with rifampicin and PBO or dsCYP6CY3.
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