46 research outputs found
Microbial Fuel Cell for Renewable Energies Generation from Manure Treatment
In the process of society, high-density livestock farms have developed rapidly to satisfy the increasing demand for meat products. Excessive wastewater from the livestock farms accordingly brought multiple pollution and deteriorate the environment, with the wastewater containing abundant chemical energy regarded as futility. Furthermore, the ingredients of wastewater varied from distinct livestock farms as a result of different animal feeding habits. Consequently, it is a necessity for specific wastewater treatment applied to a certain farm to control various pollution incidents while effectively recovering the potential chemical energy in wastewater. Microbial fuel cell, a device that converts chemical energy in the organic matter directly into electrical energy by a microorganism, is expected to be integrated with the existing wastewater treatment systems to make up for the shortcomings of existing technologies, improve the treatment efficiency and energy recovery rate. Therefore, it is a predictable trend for the microbial fuel cell to be combined with the traditional farm wastewater treatment system. This article demonstrates two traditional manure treatment methods: composting and biogas fermentation, followed by an evaluation of four advanced wastewater treatment technologies merged with microbial fuel cell. It is concluded that incorporating microbial fuel cells with separate wastewater treatment system will be a consequential sustainable development strategy in the future, with the purpose of fecal water treatment and energy recovery efficiently achieved
ANN Model-Based Simulation of the Runoff Variation in Response to Climate Change on the Qinghai-Tibet Plateau, China
Precisely quantitative assessments of stream flow response to climatic change and permafrost thawing are highly challenging and urgent in cold regions. However, due to the notably harsh environmental conditions, there is little field monitoring data of runoff in permafrost regions, which has limited the development of physically based models in these regions. To identify the impacts of climate change in the runoff process in the Three-River Headwater Region (TRHR) on the Qinghai-Tibet Plateau, two artificial neural network (ANN) models, one with three input variables (previous runoff, air temperature, and precipitation) and another with two input variables (air temperature and precipitation only), were developed to simulate and predict the runoff variation in the TRHR. The results show that the three-input variable ANN model has a superior real-time prediction capability and performs well in the simulation and forecasting of the runoff variation in the TRHR. Under the different scenarios conditions, the forecasting results of ANN model indicated that climate change has a great effect on the runoff processes in the TRHR. The results of this study are of practical significance for water resources management and the evaluation of the impacts of climatic change on the hydrological regime in long-term considerations
Identification, characterization, and function of GRP94 and HSP90β in cold stress response in cold water fish Phoxinus lagowskii
The glucose-regulated protein (GRP94) and HSP90β are highly conserved and diverse molecular chaperones that could prevent protein aggregation and denaturation while also playing an important role in cellular stress responses. We show through our study the cloning and characterization of GRP94 and HSP90β genes and analyze their mRNA expression in the brain, heart, liver, and muscle tissues of Phoxinus lagowskii after exposure to cold stress. The strong stress resistance to the temperature of this cold-water fish in high latitudes makes it a good model for this study. GRP94 and HSP90β contain a KDEL and a MEEVD motif at the C-terminus and a histidine kinase-like ATPases (HATPases-c domain) at the N-terminus. These genes were found to be highly expressed in the liver, gills, ovary, testis, and other tissues. In the brain, liver, and muscle tissue, there was an increase in GRP94 mRNA expression during early acute cold stress compared to a control fish. However, the mRNA expression levels of HSP90β increase in the brain and heart in response to exposure to acute cold stress. Relative long-term stress showed no significant difference in the GRP94 and HSP90β expression levels in the liver, heart, and muscle tissue. Significantly high expression of GRP94 was shown in the brain during 14 days, suggesting that these two genes may protect brain tissue from damage during relative long-term cold stress. Our work suggests that HSP90 enhances AKT signaling and may participate in the glucose mechanism. Furthermore, HSP90 may activate IKK signaling via AKT, resulting in a variety of immune responses. This concludes the first study to focus on the GRP94 and HSP90β functions in P. lagowskii during cold stress and provides important tools for future research into HSP90 and GRP94 genes in cold-water fish
Environmental factors driving the succession and differentiation of ecological strategy spectrum in tropical lowland rain forest
We aimed to determine the environmental driving factors underpinning successional changes in a tropical lowland rain forest in Hainan. Using hectare scale plots, we evaluated woody plant community composition and collected a variety of environmental variables. We found that the ecological strategy spectrum of communities in the four succession stages differentiated along the C-S axis, but no major communities were found in the R strategy group. The spectrum of ecological strategy of different communities is significantly different with succession, among which C strategy group is on the rise, S strategy group is on the decline, and the intermediate (INT) group strategy is on the rise after the first decline. For the C strategy group, population density and canopy openness explain most of the differences. The S strategy group are explained by slope and population density, while the first two explanatory factors of intermediate strategy group differences are slope and soil total potassium content. The change of plant ecological strategy is the result of comprehensive action of biotic factors, topographic factors and soil factors, among which biotic factors play a leading role
Face Mask Identification Using Spatial and Frequency Features in Depth Image from Time-of-Flight Camera
Face masks can effectively prevent the spread of viruses. It is necessary to determine the wearing condition of masks in various locations, such as traffic stations, hospitals, and other places with a risk of infection. Therefore, achieving fast and accurate identification in different application scenarios is an urgent problem to be solved. Contactless mask recognition can avoid the waste of human resources and the risk of exposure. We propose a novel method for face mask recognition, which is demonstrated using the spatial and frequency features from the 3D information. A ToF camera with a simple system and robust data are used to capture the depth images. The facial contour of the depth image is extracted accurately by the designed method, which can reduce the dimension of the depth data to improve the recognition speed. Additionally, the classification process is further divided into two parts. The wearing condition of the mask is first identified by features extracted from the facial contour. The types of masks are then classified by new features extracted from the spatial and frequency curves. With appropriate thresholds and a voting method, the total recall accuracy of the proposed algorithm can achieve 96.21%. Especially, the recall accuracy for images without mask can reach 99.21%
Novel Insights on 6:6 Perfluoroalkyl Phosphonic Acid-Induced Melanin Synthesis Disorders Leading to Pigmentation in Tadpoles
As alternatives to traditional per- and polyfluoroalkyl
substances,
perfluoroalkyl phosphonic acids (PFPiAs) are widely present in aquatic
environments and can potentially harm aquatic organisms. Pigmentation
affects the probability of aquatic organisms being preyed on and serves
as an important toxic endpoint of development, but little is known
about the impacts of PFPiAs on the development of aquatic organisms.
In this study, Xenopus laevis embryos
were exposed to 6:6 PFPiA (1, 10, and 100 nM) for 14 days. The developed
tadpoles exhibited evident pigmentation with increased melanin particle
size and density on the skin. Pathological and behavioral experiments
revealed that the retinal layers became thinner, reducing the photosensitivity
and disturbing the circadian rhythm of the tadpoles. Compared to the
control group, the exposed tadpoles showed higher levels but less
changes of melanin throughout the light/dark cycle, as well as distinct
oxidative damage. Consequently, the expression level of microphthalmia-associated
transcription factor (MITF), a key factor inducing melanin synthesis,
increased significantly. Molecular docking analysis suggested that
6:6 PFPiA forms strong interactions in the binding pocket of MITF,
implying that it could activate MITF directly. The activation of MITF
ultimately promotes melanin synthesis, resulting in pigmentation on
tadpoles
Study on Hydrogen Sensitivity of Ziegler–Natta Catalysts with Novel Cycloalkoxy Silane Compounds as External Electron Donor
Two novel cycloalkoxy silane compounds (ED1 and ED2) were synthesized and used as the external electron donors (EEDs) in Ziegler–Natta catalysts with diethyl 2,3-diisopropylsuccinate as internal electron donor. The results indicated that the Ziegler–Natta catalysts using ED1 and ED2 as EEDs had high catalytic activities and good stereoselectivities. The melt flow rate (MFR) and gel permeation chromatography (GPC) results revealed that the obtained polypropylene has higher MFR and lower average molecular weights than the commercial EED cyclohexyl methyl dimethoxysilane. The differential scanning calorimetry (DSC) results indicated that new isospecific active centers formed after the introduction of new external donors. The work implied that the novel EEDs could improve the hydrogen sensitivities of the catalyst system and obtain polymers with high melt flow rate
Novel Insight into the Mechanisms of Neurotoxicity Induced by 6:6 PFPiA through Disturbing the Gut–Brain Axis
As
alternatives to traditional per- and polyfluoroalkyl substances,
perfluoroalkyl phosphonic acids (PFPiAs) are frequently detected in
aquatic environments, but the neurotoxic effects and underlying mechanisms
remain unclear. In this study, male zebrafish were exposed to 6:6
PFPiA (1 and 10 nM) for 28 days, which exhibited anxiety-like symptoms.
Gut microbiome results indicated that 6:6 PFPiA significantly increased
the abundance of Gram-negative bacteria, leading to enhanced levels
of lipopolysaccharide (LPS) and inflammation in the gut. The LPS was
delivered to the brain through the gut–brain axis (GBA), damaged
the blood–brain barrier (BBB), stimulated neuroinflammation,
and caused apoptosis as well as neural injury in the brain. This mechanism
was verified by the fact that antibiotics reduced the LPS levels in
the gut and brain, accompanied by reduced inflammatory responses and
anxiety-like behavior. The BBB damage also resulted in the enhanced
accumulation of 6:6 PFPiA in the brain, where it might bind strongly
with and activate aryl hydrocarbon receptor (AhR) to induce brain
inflammation directly. Additionally, as the fish received treatment
with an inhibitor of AhR, the inflammation response and anxiety-like
behavior decreased distinctly. This study sheds light on the new mechanisms
of neurotoxicity-induced 6:6 PFPiA due to the interruption on GBA