The goal of this study was to use life cycle assessment to evaluate whether using liquid hazardous waste as an alternative fuel source in cement manufacturing processes located in the United States ...improves system environmental impact when compared with a facility using coal. Results from this study indicate that replacing coal with hazardous waste reduces the environmental impacts associated with the global warming impact, acidification impact, and freshwater ecotoxicity, while the human toxicity impacts for cancer and eutrophication-related environmental impacts increase. Reducing grid purchased electricity by recuperating waste heat from the process, cooling the exhaust gases and generating electricity to offset electrical demand, could reduce environmental impacts associated with off-site grid purchased electricity and should be considered for further environmental impact reductions. In addition, these results confirm that there are certain positive environmental effects associated with the co-burning of hazardous waste during cement manufacturing and replacing fossil fuels, such as coal, with high energy content hazardous waste.
•Replacing coal with hazardous waste reduces some environmental impacts.•Using hazardous waste increases human toxicity and eutrophication impacts.•Results confirm positive environmental effects with the co-burning of hazardous waste.
•Life cycle assessment of the HTC process was conducted using EASETECH.•HTC products and hydrochar combustion influence system environmental impact.•Emission savings from electricity generated from ...hydrochar combustion are significant.•Liquid streams need to be appropriately managed to reduce environmental impact.•Sorting of food wastes from the waste stream reduces the load to the environment.
Although there are numerous studies suggesting hydrothermal carbonization is an environmentally advantageous process for transformation of wastes to value-added products, a systems level evaluation of the environmental impacts associated with hydrothermal carbonization and subsequent hydrochar combustion has not been conducted. The specific objectives of this work are to use a life cycle assessment approach to evaluate the environmental impacts associated with the HTC of food wastes and the subsequent combustion of the generated solid product (hydrochar) for energy production, and to understand how parameters and/or components associated with food waste carbonization and subsequent hydrochar combustion influence system environmental impact. Results from this analysis indicate that HTC process water emissions and hydrochar combustion most significantly influence system environmental impact, with a net negative GWP impact resulting for all evaluated substituted energy-sources except biomass. These results illustrate the importance of electricity production from hydrochar particularly when it is used to offset coal-based energy sources. HTC process water emissions result in a net impact to the environment, indicating a need for developing appropriate management strategies. Results from this analysis also highlight a need for additional exploration of liquid and gas-phase composition, a better understanding of how changes in carbonization conditions (e.g., reaction time and temperature) influence metal and nutrient fate, and the exploration of liquid-phase treatment.
•Carbonization of food wastes was conducted at different times and temperatures.•Leaching experiments to determine solid-phase nutrient availability were conducted.•Majority of nitrogen, calcium, and ...magnesium remain integrated within the solid-phase.•Phosphorus integration with the hydrochar increases with reaction temperature and time.•Nitrogen release from the solids is small, while almost all of the phosphorus is released.
Food waste represents a rather large and currently underutilized source of potentially available and reusable nutrients. Laboratory-scale experiments evaluating the hydrothermal carbonization of food wastes collected from restaurants were conducted to understand how changes in feedstock composition and carbonization process conditions influence primary and secondary nutrient fate. Results from this work indicate that at all evaluated reaction times and temperatures, the majority of nitrogen, calcium, and magnesium remain integrated within the solid-phase, while the majority of potassium and sodium reside in the liquid-phase. The fate of phosphorus is dependent on reaction times and temperatures, with solid-phase integration increasing with higher reaction temperature and longer time. A series of leaching experiments to determine potential solid-phase nutrient availability were also conducted and indicate that, at least in the short term, nitrogen release from the solids is small, while almost all of the phosphorus present in the solids produced from carbonizing at 225 and 250°C is released. At a reaction temperature of 275°C, smaller fractions of the solid-phase total phosphorus are released as reaction times increase, likely due to increased solids incorporation. Using these data, it is estimated that up to 0.96% and 2.30% of nitrogen and phosphorus-based fertilizers, respectively, in the US can be replaced by the nutrients integrated within hydrochar and liquid-phases generated from the carbonization of currently landfilled food wastes.
Bergé D, Carmona S, Rovira M, Bulbena A, Salgado P, Vilarroya O. Gray matter volume deficits and correlation with insight and negative symptoms in first‐psychotic‐episode subjects.
Objective: To ...determine brain areas reduced in first episode of psychotic subjects and its association with lack of insight and negative symptoms.
Method: Twenty‐one drug naive first‐episode subjects and 20 controls underwent a structural MRI scan and were clinically assessed. Optimized voxel‐based‐morphometry analysis (VBM) was implemented to find between‐group differences and correlations between GM volume and: (i) lack of insight and (ii) negative symptoms.
Results: Patients showed GM reduction in prefrontal and left temporal areas. A significant correlation was found between insight and GM volume in the cerebellum (corrected P = 0.01), inferior temporal gyrus (corrected P = 0.022), medial superior frontal gyrus (corrected P < 0.001), and inferior frontal gyrus (corrected P = 0.012), as the insight decreased, the volume decreased. Negative symptoms correlated with decreased GM volume at cerebellum (corrected P = 0.037) and frontal inferior regions (corrected P < 0.001), the more negative symptoms, the less volume.
Conclusion: Our findings support an association between prefrontal, temporal, and cerebellar deficits and lack of insight in schizophrenia and confirm previous findings of GM deficits in patients since the first episode of psychosis.
Decellularized tissue matrices are promising substrates for tissue generation by stem cells to replace poorly regenerating tissues such as cartilage. However, the dense matrix of decellularized ...cartilage impedes colonisation by stem cells. Here, we show that digestion of elastin fibre bundles traversing auricular cartilage creates channels through which cells can migrate into the matrix. Human chondrocytes and bone marrow-derived mesenchymal stromal cells efficiently colonise elastin-treated scaffolds through these channels, restoring a glycosaminoglycan-rich matrix and improving mechanical properties while maintaining size and shape of the restored tissue. The scaffolds are also rapidly colonised by endogenous cartilage-forming cells in a subcutaneously implanted osteochondral biopsy model. Creating channels for cells in tissue matrices may be a broadly applicable strategy for recellularization and restoration of tissue function.
The Wnt pathway constitutes one of the most attractive candidates for modulating skeletal tissue regeneration based on its functions during skeletal development and homeostasis. Wnts participate in ...every stage of skeletogenesis, from the self-renewal and proliferation of skeletal stem cells to the specification of osteochondroprogenitor cells and the maturation of chondrocytes and osteoblasts. We propose that the function of Wnts depend upon a skeletogenic cell’s state of differentiation. In this review we summarize recent data with a focus on the roles of Wnt signaling in mesenchymal stem cell fate, osteoprogenitor cell differentiation, chondrocyte maturation, bone remodeling, and bone regeneration.
The purpose of this study is to develop regression models that describe the role of process conditions and feedstock chemical properties on carbonization product characteristics. Experimental data ...were collected and compiled from literature-reported carbonization studies and subsequently analyzed using two statistical approaches: multiple linear regression and regression trees. Results from these analyses indicate that both the multiple linear regression and regression tree models fit the product characteristics data well. The regression tree models provide valuable insight into parameter relationships. Relative weight analyses indicate that process conditions are more influential to the solid yields and liquid and gas-phase carbon contents, while feedstock properties are more influential on the hydrochar carbon content, energy content, and the normalized carbon content of the solid.
In this study, the adsorption of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) from landfill leachate onto single-walled carbon nanotubes (SWCNTs) was investigated. Different leachate solutions ...were prepared by altering the pH, ionic strength, and dissolved organic carbon (DOC) in the solutions to mimic the varying water conditions that occur in leachate during the various stages of waste decomposition. The youngest and oldest leachate solutions contained varying DOC and background chemistry and were represented by leachate Type A (pH = 5.0; DOC = 2500 mg/L; conductivity = 12,500 μS/cm; Ca
2+ = 1200 mg/L; Mg
2+ = 470 mg/L) and Type E (pH = 7.5; DOC = 250 mg/L; conductivity = 3250 μS/cm; Ca
2+ = 60 mg/L; Mg
2+ = 180 mg/L). These solutions were subsequently combined in different ratios to produce intermediate solutions, labeled B–D, to replicate time-dependent changes in leachate composition. Overall, a larger fraction of EE2 was removed as compared to BPA, consistent with its higher log K
OW value. The total removal of BPA and EE2 decreased in older leachate solutions, with the adsorptive capacity of SWCNTs decreasing in the order of leachate Type A > Type B > Type C > Type D > Type E. An increase in the pH from 3.5 to 11 decreased the adsorption of BPA by 22% in young leachate and by 10% in old leachate. The changes in pH did not affect the adsorption of EE2 in the young leachate, but did reduce adsorption by 32% in the old leachate. Adjusting the ionic strength using Na
+ did not significantly impact adsorption, while increasing the concentration of Ca
2+ resulted in a 12% increase in the adsorption of BPA and a 19% increase in the adsorption of EE2. DOC was revealed to be the most influential parameter in this study. In the presence of hydrophilic DOC, represented by glucose in this study, adsorption of the endocrine disrupting compounds (EDCs) onto the SWCNTs was not affected. In the absence of SWCNTs, hydrophobic DOC (i.e., humic acid) adsorbed 15–20% of BPA and EE2. However, when the humic acid and SWCNTs were both present, the overall adsorptive capacity of the SWCNTs was reduced. Hydrophobic (π-π electron donor-acceptor) interactions between the EDCs and the constituents in the leachate, as well as interactions between the SWCNTs and the EDCs, are proposed as potential adsorption mechanisms for BPA and EE2 onto SWCNTs.
► We studied the adsorption of BPA and EE2 from landfill leachate onto single-walled carbon nanotubes. ► This study demonstrated high removal efficiencies of BPA and EE2 from landfill leachate using SWCNTs. ► The adsorptive capacity of the SWCNTs was higher for EE2 than BPA, due to the higher log K
OW value of EE2. ► The most influential parameter on the adsorption of EDCs onto SWCNTs was DOC.
H.E.S.S.—The High Energy Stereoscopic System—is a new system of large atmospheric Cherenkov telescopes for GeV/TeV γ-ray astronomy. This paper describes the trigger system of H.E.S.S. with emphasis ...on the multi-telescope array level trigger. The system trigger requires the simultaneous detection of air-showers by several telescopes at the hardware level. This requirement allows a suppression of background events which in turn leads to a lower system energy threshold for the detection of γ-rays. The implementation of the H.E.S.S. trigger system is presented along with data taken to characterise its performance.
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