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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2008.12.008 Byline: Guiqin Wang (a), Li Qin (b), Guoxue Li (a), Lijun Chen (c) Abstract: Site selection is an important and necessary issue for waste management in fast-growing regions. Because of the complexity of waste management systems, the selection of the appropriate solid waste landfill site requires consideration of multiple alternative solutions and evaluation criteria. Based on actual conditions of the study area, we considered economic factors, calculated criteria weights using the analytical hierarchy process (AHP), and built a hierarchy model for solving the solid waste landfill site-selection problem in Beijing, China. A geographic information system (GIS) was used to manipulate and present spatial data. All maps are graded from 1 (lowest suitability) to 5 (highest suitability) using spatial information technologies. The candidate sites were determined by aggregation based on the criteria weights. The candidate sites are divided by 'best', 'good' and 'unsuitable' landfill areas. Best landfill areas represent optimal sites; good landfill areas can be used as back-up candidate sites. Our work offers a siting methodology and provides essential support for decision-makers in the assessment of waste management problems in Beijing and other rapidly developing cities in developing countries. Author Affiliation: (a) College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094, China (b) Agro-Environmental Protection Institute of the Ministry of Agriculture, Tianjin 300191, China (c) College of Food, Agricultural, and Environmental Sciences, Ohio State University, Columbus, OH 43210, USA Article History: Received 10 January 2008; Revised 20 August 2008; Accepted 1 December 2008

Abstract: The Fe3O4 nanoparticles were prepared by a novel wet-chemical method which shows its highly synthesizing efficiency and controllability. A possible formation mechanism was also proposed to explain the synthesizing process. X-ray diffraction (XRD) and transmission electron microscope (TEM) were employed and yielded an examination of an average diameter of 77nm of the as-synthesized Fe3O4 nanoparticles with face-centered cubic structure. Vibrating sample magnetometer (VSM) and vector network analyzer were employed to measure the magnetic property and electromagnetic parameters of the nanoparticles, then reflection losses (RL (dB)) were calculated in the frequency range of 2–18GHz. A large saturation magnetization (72.36emu/g) and high coercivity (95Oe) were determined and indicated that the Fe3O4 nanoparticles own strong magnetic performance. Following simulation results showed that the lowest reflection loss of the sample was −21.2dB at 5.6GHz with layer thickness of 6mm. Effect of nanometer-sized further provided an explanation for the excellent microwave absorption behavior shown by the Fe3O4 nanoparticles. [Copyright &y& Elsevier]

Abstract: The flake-shaped barium titanate (FBT) was prepared by a modified sol–gel method, and their microstructure and electromagnetic (EM) properties (2–18GHz) were investigated by means of differential thermal analysis (DTA), thermogravimetry analysis (TG), X-ray diffraction (XRD), scanning electronic microscope (SEM) and a network analyser. The reflection loss R of FBT (annealing at different temperatures from 700 to 1200°C)/paraffin composite samples with thickness of 1mm and FBT (annealing at 1000°C)/paraffin composite samples with different thickness from 1 to 5mm were calculated in 2–18GHz using the relative complex permittivity and permeability according to the transmit-line theory. It was found that the electromagnetic characteristics and the wave absorption properties of FBT were improved. The maximal reflection loss of FBT (annealing at 1000°C)/paraffin composite sample reached −29.6dB at 12GHz with a matching thickness of 4mm. [Copyright &y& Elsevier]

Immune checkpoint inhibitors have some efficacy in the treatment of hepatocellular carcinoma (HCC). Programmed cell death 1 ligand 1 (PD-L1), expressed on some cancer cells, binds to the receptor programmed cell death 1 (PDCD1, also called PD1) on T cells to prevent their proliferation and reduce the antigen-tumor immune response. Immune cells that infiltrate some types of HCCs secrete interferon gamma (IFNG). Some HCC cells express myocyte enhancer factor 2D (MEF2D), which has been associated with shorter survival times of patients. We studied whether HCC cell expression of MEF2D regulates expression of PD-L1 in response to IFNG. We analyzed immune cells from 20 fresh HCC tissues by flow cytometry. We analyzed 225 fixed HCC tissues (from 2 cohorts) from patients in China by immunohistochemistry and obtained survival data. We created mice with liver-specific knockout of MEF2D (MEF2DLPC-KO mice). We knocked out or knocked down MEF2D, E1A binding protein p300 (p300), or sirtuin 7 (SIRT7) in SMMC-7721, Huh7, H22, and Hepa1-6 HCC cell lines, some incubated with IFNG. We analyzed liver tissues from mice and cell lines by RNA sequencing, immunoblot, dual luciferase reporter, and chromatin precipitation assays. MEF2D protein acetylation and proteins that interact with MEF2D were identified by coimmunoprecipitation and pull-down assays. H22 cells, with MEF2D knockout or without (controls), were transplanted into BALB/c mice, and some mice were given antibodies to deplete T cells. Mice bearing orthotopic tumors grown from HCC cells, with or without knockout of SIRT7, were given injections of an antibody against PD1. Growth of tumors was measured, and tumors were analyzed by immunohistochemistry and flow cytometry. In human HCC specimens, we found an inverse correlation between level of MEF2D and numbers of CD4+ and CD8+ T cells; level of MEF2D correlated with percentages of PD1-positive or TIM3-positive CD8+ T cells. Knockout of MEF2D from H22 cells reduced their growth as allograft tumors in immune-competent mice but not in immune-deficient mice or mice with depletion of CD8+ T cells. When MEF2D-knockout cells were injected into immune-competent mice, they formed smaller tumors that had increased infiltration and activation of T cells compared with control HCC cells. In human and mouse HCC cells, MEF2D knockdown or knockout reduced expression of PD-L1. MEF2D bound the promoter region of the CD274 gene (encodes PD-L1) and activated its transcription. Overexpression of p300 in HCC cells, or knockout of SIRT7, promoted acetylation of MEF2D and increased its binding, along with acetylated histones, to the promoter region of CD274. Exposure of HCC cells to IFNG induced expression of p300 and its binding MEF2D, which reduced the interaction between MEF2D and SIRT7. MEF2D-induced expression of PD-L1 upon IFNG exposure was independent of interferon-regulatory factors 1 or 9. In HCC cells not exposed to IFNG, SIRT7 formed a complex with MEF2D that attenuated expression of PD-L1. Knockout of SIRT7 reduced proliferation of HCC cells and growth of tumors in immune-deficient mice. Compared with allograft tumors grown from control HCC cells, in immune-competent mice, tumors grown from SIRT7-knockout HCC cells expressed higher levels of PD-L1 and had reduced infiltration and activation of T cells. In immune-competent mice given antibodies to PD1, allograft tumors grew more slowly from SIRT7-knockout HCC cells than from control HCC cells. Expression of MEF2D by HCC cells increases their expression of PD-L1, which prevents CD8+ T-cell–mediated antitumor immunity. When HCC cells are exposed to IFNG, p300 acetylates MEF2D, causing it to bind the CD274 gene promoter and up-regulate PD-L1 expression. In addition to promoting HCC cell proliferation, SIRT7 reduced acetylation of MEF2D and expression of PD-L1 in HCC cells not exposed to IFNG. Strategies to manipulate this pathway might increase the efficacy of immune therapies for HCC. [ABSTRACT FROM AUTHOR]

Abstract: Petrography and mineral chemistry of two new ureilites, GRV 021512 and 022931, from the Grove Mountains, Antarctica, are reported in this paper. GRV 021512 exhibits a typical ureilite texture, and consists of 48.3% olivine, 9.4% pigeonite and 38.1% carbonaceous interstitial material and/or reduction product. GRV 022931 has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3% carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed. [Copyright &y& Elsevier]

This study investigates the influence of aeration on volatile sulfur compounds (VSCs) and ammonia (NH 3 ) emissions during kitchen waste composting. Aerobic composting of kitchen waste and cornstalks was conducted at a ratio of 85:15 (wet weight basis) in 60 L reactors for 30 days. The gas emissions were analyzed with force aeration at rates of 0.1 (A1), 0.2 (A2) and 0.3 (A3) L (kg DM min) −1 , respectively. Results showed that VSCs emission at the low aeration rate (A1) was more significant than that at other two rates (i.e., A2 and A3 treatment), where no considerable emission difference was observed. On the other hand, NH 3 emission reduced as the aeration rate decreased. It is noteworthy that the aeration rate did not significantly affect the compost quality. These results suggest that the aeration rate of 0.2 L (kg DM min) −1 may be applied to control VSCs and NH 3 emissions during kitchen waste composting. [ABSTRACT FROM AUTHOR]