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Peacock Barlow
Peacock Barlow

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Bio-based hybrids made through wood fibres through self-bonding technologies.

In the present research, application of waste edible oil (WEO) as a suitable and abundant source for biodiesel production using CaO@MgO nanocatalyst derived from waste chicken eggshells was studied. To this end, FT-IR, XRD, SEM, EDX, Map, and TEM analyses were performed to investigate characteristics of the CaO@MgO nanocatalyst. Also, the physical properties of the biodiesel such as flash point, kinematic viscosity, density, distillation point, cloud point, pour point, cetane number, oxidation stability, and acid number were determined according to the international standards. In addition, FT-IR and HNMR analyses were used to determine the biodiesel characteristics. Moreover, the produced catalyst was successively reused for up to 6 cycles and the results showed that the catalytic activity of the catalyst produced was sufficient for biodiesel production from WEO for up to three cycles, beyond which its catalytic activity decreased. The present work further considered the effects of different parameters on biodiesel production using central composite design to determine optimal conditions. According to the results, the highest biodiesel conversion yield (98.37%) was achieved in a reaction time of 7.08 h, reaction temperature of 69.37 °C, methanol-to-oil ratio of 16.71, and catalyst concentration of 4.571 wt% which shows the highest biodiesel conversion yield ever achieved from waste edible oil. 5-lipoxygenase (5-LO), coded by the ALOX5 gene, is expressed in leukocytes and catalyzes the formation of leukotrienes, pro-inflammatory lipid mediators. Leukotrienes are central to immune responses, but are also involved in inflammatory disorders and 5-LO expression is associated with leukemia stem cell survival. It is therefore important to understand mechanisms that control 5-LO expression. This study investigated the control of 5-LO expression and leukotriene biosynthesis following the maturation of human monocytic cells. MonoMac-1 (MM1) and THP-1 cells were incubated for up to 72 h with or without LPS and TGF-β. LPS, but not TGF-β, increased CD14 expression in both MM1 and THP-1 cells. Incubation with LPS (100 ng/ml) and TGF-β (1 ng/ml) synergistically increased the capacity of MM1 cells to produce 5-LO products from undetectable levels to 40±5 pmol/106 cells. 5-LO product biosynthesis in THP-1 cells increased 25-fold. A synergistic effect of LPS and TGF-β was measured with increases in 5-LO mRNA of 54- and 13-fold in MM1 and THP-1 cells, respectively. 5-LO protein expression increased significantly in both MM1 and THP-1 cells. ALOX5 promoter activity was significantly elevated >2-fold in both cell lines following LPS treatment, but TGF-β was without effect. The main 5-LO products were cysteinyl-leukotrienes, however LPS and TGF-β did not impact on the capacity of the cells to metabolize leukotriene A4. Overall, this study demonstrates that receptor-mediated stimulation of MM1 and THP-1 cells by LPS is associated with increased 5-LO expression. This represents a new mechanism by which leukotriene biosynthesis can be modulated by pathological agents. Studies have showed that some of the most common male reproductive disorders present in adult life might have a fetal origin. Perfluorooctane sulfonic (PFOS) is one of the major environmental pollutants that may affect the development of male reproductive system if exposed during fetal or pubertal periods. However, whether PFOS exposure during fetal period affects testicular functions in the adult is still unclear. Herein, we investigated the effects of a brief gestational exposure to PFOS on the development of adult Leydig- and Sertoli-cells in the male offspring. Eighteen pregnant Sprague-Dawley rats were randomly divided into three groups and each received 0, 1 or 5 mg/kg/day PFOS from gestational day 5-20. The testicular functions of F1 males were evaluated on day 1, 35 and 90 after birth. PFOS treatment significantly decreased serum testosterone levels of animals by all three ages examined. The expression level of multiple mRNAs and proteins of Leydig (Scarb1, Cyp11a1, Cyp17a1 and Hsd17b3) and Sertoli (Dhh and Sox9) cells were also down-regulated by day 1 and 90. PFOS exposure might also inhibit Leydig cell proliferation since the number of PCNA-positive Leydig cells were significantly reduced by postnatal day 35. Accompanied by changes in Leydig cell proliferation and differentiation, PFOS also significantly reduced phosphorylation of glycogen synthase kinase-3β while increased phosphorylation of β-catenin. In conclusion, gestational PFOS exposure may have significant long-term effects on adult testicular functions of the F1 offspring. read more Changes in Wnt signaling may play a role in the process. Freshwater systems serve as important sources and transportation routes for marine microplastic pollution, and inadequate attention has been paid to this situation. Data on microplastic pollution of typical seagoing rivers in northern China are lacking. In the current study, we investigated the distribution and characteristics of microplastics in the main stream of the Haihe River, which flows through a metropolis with a high population density and level of industrialization and then flows into the Bohai Sea. The microplastic samples were collected by manta trawls with pore sizes of 333 μm, and the microplastic concentrations ranged from 0.69 to 74.95 items/m3. Fibers dominated in the surface water of the Haihe River; their shapes that were categorized as fibers, film, foam, fragments, and spheres, and contributed 17.4-86.7% of the total microplastics studied. The size distribution of the microplastics was concentrated in a range of 100-1000 μm, with 54.7% of the total sizes corresponding to the 333-μm trawl. Micro-Fourier transform infrared (μ-FT-IR) spectra showed that the main components were polyethylene, poly(ethylene-propylene) copolymer, and polypropylene. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) measurements revealed scratches, micropores, and cracks on the surfaces of the microplastics due to mechanical friction, chemical oxidation and degradation processes. The results of this study confirmed the high abundance and high diversity of microplastics in an urban river and indicated appreciable impacts from point-source inputs on the microplastic pollution, such as effluents from wastewater treatment plants (WWTPs).read more

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