Viborgsunesen7130

2,4-Dinitrophenol (2,4-DNP) is an important organic environmental pollutant that is highly toxic to all forms of living organisms. A gram-positive strain (designated XM24D) was isolated from 2,4-DNP-contaminated soil by an enrichment technique.

The study was designed to analyze the ability of XM24D to degrade 2,4-DNP and its analogs and to reveal the degradation pathways of these aromatic compounds.

The degradation ability of XM24D was tested by a growth experiment. 2,4-DNP and its analog degradation pathways were predicted by genome and comparative transcriptome sequencing.

Growth profiles showed that XM24D was able to utilize 2,4-DNP as the sole source of carbon, nitrogen and energy. Analogs of 2,4-DNP, including 4-nitrophenol (PNP) and 2-chloro-4-nitrophenol (2C4NP), can also be degraded by XM24D. Genome analysis showed that the XM24D genome contains two chromosomes with a combined size of 9.08Mb and an average GC content of 67.07 %. Average nucleotide identity analysis indicated that Rhodococcus imtechensis RKJ300 is the most closely related strain to XM24D. Comparative transcriptome analysis revealed that the 2,4-DNP/PNP/2C4NP degradation pathway in XM24D is highly similar in sequence and organization to the 2,4-DNP degradation pathway in Rhodococcus opacus HL PM-1, the PNP degradation pathway in Rhodococcus opacus SAO101 and the 2C4NP degradation pathway in Rhodococcus imtechensis RKJ300. These results suggested that 2,4-DNP/PNP/2C4NP was degraded via the 2,4-dinitrocyclohexanone/4-nitrocatechol/hydroxyquinol pathway in XM24D.

Genomic and transcriptomic information on XM24D provides a valuable reference for further investigating the evolutionary characteristics of nitrophenol degradation pathways in microorganisms.

Genomic and transcriptomic information on XM24D provides a valuable reference for further investigating the evolutionary characteristics of nitrophenol degradation pathways in microorganisms.This study provides new insight by introducing the role of fiscal decentralization and natural resources rent in affecting CO2 emissions. For assessing this objective, this paper use panel data from seven highly fiscal decentralized Organization for Economic Cooperation and Development (OECD) countries from 1990 to 2018. For empirical analysis, we use the Westerlund test and cross-sectional autoregressive distributive lag model. In order to ascertain the integration order of variables, the study utilizes the Pesaran second-generation unit-root test. The findings reveal that all the variables are stationary at first difference. The long-run results confirm that fiscal decentralization and natural resources rent improve the atmosphere by reducing CO2 emissions. Moreover, gross domestic product and total natural resources rent increase, while improvement in institutional quality reduces CO2 emissions. For policy implication, this study recommends that transferring the power to the local governments will further reduce CO2 emissions and shift these countries to more environmentally friendly sources.A new two-step modification method has been proposed where 1.8% HCl and 3.1% HNO3 were applied to modify the interlayer of vermiculite (VMT). This product was given 90 °C of heat in 30% H2SO4 solution that was used for Pb (II) and Sb (III) adsorption. The EDTA presence on the individual adsorption was assessed. X-ray diffraction revealed that the VMT inter-stratified reflection through acid intercalation within the interlayer decreased the parallel gaps between the atoms, witnessing on the outer-sphere adsorption. The driving force was found electrostatic, which fits well with pseudo-second-order kinetics and Langmuir isotherm. The Pb (II) and Sb (III) uptake followed descending order adsorption with increasing concentration of chelating EDTA. Three consecutive desorption cycles revealed that the prepared adsorbent was suitable that may be regarded as a good candidate for complex wastewaters.Cadmium (Cd) is one of the toxic elements entering the food chain in various ways, including chemical fertilizers. This study aimed to assess different amounts and forms of available Cd in soils under wheat cultivation affected by long-term use of phosphorus chemical fertilizers and also to study the rate of Cd intake by people with age and gender differences. To investigate the Cd status in wheat-cultivated lands, 105 soil samples and also 24 wheat samples were collected from three land uses of rainfed, irrigated, and control one. Phosphorus levels were also measured in soil samples to investigate the relationship between the amount of chemical fertilizer consumption and the amount of Cd. The mean values of available Cd were 0.15, 0.18, and 0.08 (mg/kg) under three land-use types of rainfed, irrigated, and control one, respectively, and the mean values of total Cd were also 1.9, 2.22, and 1.30 in the rainfed land, irrigated land, and control one, respectively. The results showed that the amount of available and total Cd in the irrigated and rainfed lands was higher than the amount of Cd in the control sample. According to the results of Cd fractionation, the highest amounts of Cd were in the residual, carbonate, organic, soluble, and exchangeable fractions, respectively. The amounts of Cd in the three parts of root, stem, and grain were 1.08, 0.65, 0.91 (mg/kg), respectively. Finally, the results showed that the rate of Cd entry into the children's body was higher than that of adults and the elderly.Substantial pieces of evidence support the potential of exogenous toxins in disrupting neuroimmune homeostasis. It appears that mycotoxins are one of the noticeable sources of naturally occurring substances dysregulating the immune system, which involves the physiology of many organs, such as the central nervous system (CNS). The induction of inflammatory responses in microglial cells and astrocytes, the CNS resident cells with immunological characteristics, could interrupt the hemostasis upon even with low-level exposure to mycotoxins. The inevitable widespread occurrence of a low level of mycotoxins in foods and feed is likely increasing worldwide, predisposing individuals to potential neuroimmunological dysregulations. This paper reviews the current understanding of mycotoxins' neuro-immunotoxic features under low-dose exposure and the possible ways for detoxification and clearance as a perspective.Tunnel excavation has significant disturbance on groundwater system and related geo-environment, especially in karst regions like southwestern China. The present research was conducted to quantitatively understand the negative impacts posed by tunnel construction on the karst groundwater system and reveal the behavior of karst groundwater system under the tunnel disturbance, with the aid of field survey, hydrogeological analysis, and numerical simulation. The results suggested that negative impacts such as loss of surface and underground water, ground collapse, and house deformation would be posed directly and indirectly to the karst groundwater system and its dependent geo-environment as the result of groundwater level drawdown by tunnel excavation. The degree and range of groundwater drainage impact were determined by the lithological and hydrogeological characteristics of strata. These negative impacts were dominantly distributed in the karst depressions valleys, and the direct ones occurred at first and followed by the indirect ones. Simulation results showed groundwater level drawdown would not occur synchronously in spatial, but always occurred around the tunnel axis at first and gradually expanded towards far away over time. The maximum disturbance on groundwater system can reach to approximately 25 m vertically and 3000 m horizontally for present modeling tunnel. With the aid of numeral simulation, three response stages were identified for the karst groundwater system behavior to the tunnel disturbance. The impacts of tunnel practice on groundwater and surface water bodies can be gradually eliminated since the second stage, but would continue if existing failure of tunnel waterproof until a new balance state achieved. The present research can improve the understanding of the impacts of tunnel excavation on karst groundwater system and dependent geo-environment, and provide reference to the protection of water resources and geo-environment in karst regions like Chongqing worldwide.Constructed wetland is a common measure for water purification and biodiversity conservation, but the mechanism of carbon storage is still unclear. Here, we researched the content and composition of soil organic carbon (SOC) and the influencing factors in surface sediment in surface flow constructed wetlands (SFCW) and subsurface flow constructed wetlands (SSFCW). Results showed that the content and storage of SOC in SSFCW were significantly higher than those in SFCW. check details However, the higher proportion of light fraction organic carbon (LFOC) and lower proportion of heavy fraction organic carbon (HFOC) in SSFCW indicated that SSFCW had less stable organic carbon storage than SFCW. The composition of SOC in the two types of constructed wetlands was mainly affected by total nitrogen, which suggesting carbon-nitrogen coupling in constructed wetlands. The abundant microbial species in SSFCW and their positive correlation with SOC could explain the higher carbon storage in SSFCW than in SFCW. In addition, plant biomass was the principle factor limiting LFOC proportion in SFCW, while it was moisture content in SSFCW. The study has important implications for understanding and management of ecological function of carbon sequestration in contrasted wetlands, and also provides a special perspective to understand the carbon storage mechanism in wetlands.Louhajang River, Bangladesh, which crosses Tangail as a densely industrialized and urbanized city, supplies water for different purposes. This study reports the levels of pH, electrical conductivity (EC), and some toxic heavy metals in 40 water samples collected during the summer and winter seasons from Louhajang River. The winter season reported higher levels of the examined parameters than the summer season with significant variation (p 1.0 × 10-6, indicating possible cancer risk. The adopted collection of different approaches (comparison against standard levels of toxicants, statistical analysis, spatial distribution, and health risk assessment) successfully demonstrates a whole picture of the environmental status of Louhajang River, Bangladesh.Passivation of heavy metals is one of the most efficient techniques to remediate soil pollution. However, passivators with single component are usually unsatisfactory in the case of multi-metal contaminated soils. To resolve this problem, a series of combined passivators containing different ratios of Fe-Mn ore, Fe powder, zeolite, bentonite, etc. were designed and used to study their effects on the growth, heavy metal accumulation, and the antioxidant response of Chinese cabbage (Brassica chinensis L.) as well as the soil available forms of heavy metals in a copper refinery's multi-metal (As, Cd, Pb, Cu) contaminated yellow-brown soil and an artificially contaminated (As, Cd, Pb, Cu) calcareous alluvial soil. The results showed that compared with the control, the addition of combined passivators significantly promoted cabbage growth, with the biomass increase up to 1.77 and 3.54 times in yellow-brown soil and calcareous alluvial soil, respectively. The activity of antioxidant enzymes (SOD, CAT, POD) and the content of malondialdehyde (MDA) and glutathione (GSH) decreased, while the chlorophyll content increased significantly, as compared with no passivators.