Fluoroalkylether Compounds Affect Microbial Community Structures and Abundance of Nitrogen cycle-related Genes in Soil-microbe-plant Systems

As alternatives to conventional PFAS, ether-PFAS have not been studied much. Their effects to microbial communities, in particular, have not been reported. In this study, we investigated change of microbial community in soil-plant systems dosed with undecafluoro-2-methyl-3-oxahexanoic acid (GenX), dodecafluoro-3H-4,8-dioxanonanoate (ADONA), or 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B). It is revealed that the community structure and the species diversity were significantly affected by each of the three ether-PFAS at the two tested concentrations. The only exception was GenX at the low concentration. With respect to nitrification, amoA genes in ammonia oxidizing bacteria were not significantly affected while amoA gene abundance in ammonia oxidizing archaea was significantly decreased. In terms of denitrification, ether-PFAS at different concentrations had different impacts to the three studied genes: nirS, nirK, and norZ. This study thus demonstrated that ether-PFAS could bring significant changes to the soil microbial community structure and functions

Atypical chemokine receptors predict lymph node metastasis and prognosis in patients with cervical squamous cell cancer

AbstractObjectiveAtypical chemokine receptors (ACRs), including CCX-CKR, DARC, and D6, have been reported to be involved in cancer invasion and metastasis. The objective of this study was to investigate the prognostic importance of ACRs in patients with cervical squamous cell carcinoma (CSCC).MethodsThe expression of three ACRs was investigated by immunohistochemical (IHC) examination in a total of 317 cervical specimens including 40 normal cervical tissues, 50 cases of carcinoma in situ of cervix (CIS), and 227 cases of CSCC by immunohistochemistry.ResultsThe expression rate of DARC and CCX-CKR in CSCC, CIS, and normal cervix increased gradually (p<0.01). D6 expression is decreased in CSCC compared to either in CIS or in normal cervix (p<0.05). In addition, the expression of CCL2 and CCL19 was inversely associated with ACR expression (p<0.05), while that of LCA was positively correlated with ACR expression (p<0.05). Moreover, DARC expression, CCX-CKR expression, and ACR coexpression were negatively correlated with lymph node metastasis (P<0.01). D6 expression and ACR coexpression were negatively related to tumor size (p=0.018) and recurrence (p=0.028). In multivariate Cox regression analysis, CCX-CKR expression was a positive indicator for overall survival (p=0.008), and D6 expression was an independent predictor of both overall and recurrence-free survival (p=0.041) in CSCC.ConclusionsOur results suggest that the loss of ACRs may play important roles in the tumorigenesis and migration of cervical cancer. ACR expression may be considered as prognostic markers in patients with CSCC

Study on the adaptability and optimization of boom replacement methods for suspension bridges

To ensure the safe operation of bridges, the study of methods and techniques for boom replacement has become a crucial aspect of the scientific maintenance of suspension bridges. This study focuses on analyzing the bridge responses and evaluating the applicability of three different boom replacement methods: single-point, three-point and five-point, using finite element calculations. A sea-crossing suspension bridge is taken as a case study to simulate the process of boom replacement using temporary booms. Consequently, the optimal replacement method for booms of varying lengths is determined. Meanwhile, this research proposes a quantitative basis for classifying boom lengths based on calculation data and analysis results to determine the suitable boom lengths for different replacement methods. Besides, a comparison of the relationship between the force transmission efficiency of temporary booms and boom length reveals that longer booms exhibit lower force transmission efficiency, with the efficiency decreasing at a faster rate as boom length increases. Overall, these findings provide a theoretical basis for the study of boom replacement in suspension bridges

Laboratory scale optimization of alkali pretreatment for improvingenzymatic hydrolysis of sweet sorghum bagasse

Sweet sorghum has been identified as a promising feedstock for biological conversion to fuels as wellas other chemicals. The lignocellulosic stalk of sweet sorghum, called sweet sorghum bagasse (SSB) isa potential source of lignocellulosic biofuel. The primary goal of this study was to determine optimalalkali (lime: Ca(OH)2and lye: NaOH) pretreatment conditions to obtain higher yield of total reducingsugar while reducing the lignin content for biofuel production from SSB. Biomass conversion and ligninremoval were simultaneously optimized through four quadratic models analyzed by response surfacemethodology (RSM). The optimal conditions for lime pretreatment was 1.7% (w/v) lime concentration,6.0% (w/v) SSB loading, 2.4 h pretreatment time with predicted yields of 85.6 total biomass conversionand 35.5% lignin reduction. For lye pretreatment, 2% (w/v) alkali, 6.8% SSB loading and 2.3 h durationwere the optimal levels with predicted biomass conversion and lignin reduction of 92.9% and 50.0%,respectively. More intensive pretreatment conditions removed higher amounts of hemicelluloses andcellulose. Fourier transform infrared spectroscopy (FTIR) spectrum and scanning electron microscope(SEM) image revealed compositional and microstructural changes caused by the alkali pretreatment

Bioleaching of trace elements and rare earth elements from coal fly ash

Abstract Coal fly ash originated from coal combustion has high concentrations of metals. If suitable leaching techniques are identified, then coal fly ash could serve as a useful source of valuable minerals including rare earth elements (REEs). In this study, three microbial strains, Candida bombicola, Phanerochaete chrysosporium and Cryptococcus curvatus were tested on their performance of leaching trace elements and REEs from fly ash. Through comparing mineral loss and leaching efficiencies resulting from indirect leaching or use of the culture supernatant, C. bombicola was identified to be the best leading to the highest mineral loss and extracting efficiencies of trace elements and REEs among the three strains. The highest mineral loss observed from using the supernatant of this yeast strain was 59.7%. Among all trace elements, As and Mo had the highest leaching efficiency of 80.9% and 79.5%, respectively. The same leaching test led to 67.7% of Yb and 64.6% of Er dissolved from the ash. This study, thus, demonstrated that bioleaching is feasible for leaching metals out of fly ash. The C. bombicola strain deserves further investigation due to its robust actions on metal leaching

Optimizing Leaching of Rare Earth Elements from Red Mud and Spent Fluorescent Lamp Phosphors Using Levulinic Acid

Although various hydrometallurgical and solvometallurgical efforts have been made to extract REEs from end-of-life (EoL) products and waste, a systematic and statistical analysis of the impacts of leaching parameters to optimize the leaching process using organic acids is necessary, but lacking in the literature. This study employed the response surface methodology to develop mathematical models for optimal leaching by levulinic acid (LevA) of REEs in two waste materials, namely red mud and spent fluorescent lamp phosphors. The established models exhibited excellent statistical properties, in terms of significance, fitting, prediction, and error distribution. For red mud, the optimal conditions of liquid-to-solid ratio (L/S; v/w) of 40, temperature of 70 &deg;C, and duration of 60 h led to 100% leaching of REEs excluding Sc. At the same L/S and temperature, &gt;98.7% of REEs were leached from fluorescent phosphors after 96 h. The SEM&ndash;EDS analysis of the waste materials revealed and confirmed morphological and compositional changes after leaching under the optimal conditions

Optimizing Leaching of Rare Earth Elements from Red Mud and Spent Fluorescent Lamp Phosphors Using Levulinic Acid

Although various hydrometallurgical and solvometallurgical efforts have been made to extract REEs from end-of-life (EoL) products and waste, a systematic and statistical analysis of the impacts of leaching parameters to optimize the leaching process using organic acids is necessary, but lacking in the literature. This study employed the response surface methodology to develop mathematical models for optimal leaching by levulinic acid (LevA) of REEs in two waste materials, namely red mud and spent fluorescent lamp phosphors. The established models exhibited excellent statistical properties, in terms of significance, fitting, prediction, and error distribution. For red mud, the optimal conditions of liquid-to-solid ratio (L/S; v/w) of 40, temperature of 70 °C, and duration of 60 h led to 100% leaching of REEs excluding Sc. At the same L/S and temperature, >98.7% of REEs were leached from fluorescent phosphors after 96 h. The SEM–EDS analysis of the waste materials revealed and confirmed morphological and compositional changes after leaching under the optimal conditions

Experimental study of local scour around truncated piles in oscillatory flow

The paper presents an experimental study of local scour around truncated vertical piles subject to oscillatory flow. The experiments were conducted with six height-to-diameter ratios (h/D =0.25~3.5) and three KC numbers (33, 52 and 80). The development of scour depth around the pile was reported. It was found that the effect of h/D on the scour depth reduces with increasing KC, and h/D does not affect the finial scour depth anymore when h/D _ 2.5. For the three KC numbers tested here, the scour time scale reduces with the increase of h/D when h/D _ 0.5. The finial scour profiles were scanned through a three-dimensional scanner. The slope angle of the scour hole was extracted from the three-dimensional scan