CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier

Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.

Anti-Saccharomyces cerevisiae antibody titers are stable over time in Crohn's patients and are not inducible in murine models of colitis

AIM: To investigate ASCA production over time in CD and murine colitis in order to further our understanding of their etiology.MATERIALS AND METHODS: Sixty-six CD patients were compared to ulcerative colitis (UC) and irritable bowel syndrome patients with respect to ASCA production as measured by ELISA. ASCA IgG or IgA positivity as well as change in titers over a period of up to 3 years (ΔIgG/A) was correlated with clinical parameters such as CD activity index (CDAI) and C-reactive protein levels (CRP). Moreover, two murine models of colitis (DSS and IL-10 knock out) were compared to control animals with respect to ASCA titers after oral yeast exposure.RESULTS: ASCA IgG and IgA titers are stable over time in CD and non-CD patients. Fistular disease was associated with a higher rate of ASCA IgA positivity (P = 0.014). Ileal disease was found to have a significant influence on the ΔIgG of ASCA (P=0.032). There was no correlation found between ASCA positivity or ΔIgG/A and clinical parameters of CD: CDAI and CRP. In mice,neither healthy animals nor animals with DSS-induced or spontaneous colitis exhibited a marked increase in ASCA titers after high-dose yeast exposure. On the other hand, mice immunized intraperitoneally with mannan plus adjuvant showed a marked and significant increase in ASCA titers compared to adjuvant-only immunized controls (P=0.014).CONCLUSION: The propensity to produce ASCA in a subgroup of CD patients is largely genetically predetermined as evidenced by their stability and lack of correlation with clinical disease activity parameters. Furthermore,in animal models of colitis, mere oral exposure of mice to yeast does not lead to the induction of marked ASCA titers irrespective of concomitant colonic inflammation.Hence, environment may play only a minor role in inducing ASCA.

Partial overlap of anti-mycobacterial,and anti-Saccharomyces cerevisiae mannan antibodies in Crohn's disease

AIM:To test whether humoral immune reaction against mycobacteria may play a role in anti-Saccharomyces cerevisiae antibodies(ASCA) generation in Crohn's disease(CD) and/or whether it correlates with clinical subtypes. METHODS:The dominant ASCA epitope was detected by Galanthus nivalis lectin(GNL)-binding assay. ASCA and IgG against mycobacterial lysates(M avium,M smegmatis,M chelonae,M bovis BCG,M avium ssp. paratuberculosis(MAP)] or purified lipoarabinomannans(LAM) were detected by ELISA. ASCA and anti-mycobacterial antibodies were affinity purified to assess cross-reactivities. Anti-mycobacterial IgG were induced by BCG-infection of mice. RESULTS:GNL bound to different extents to mycobacterial lysates,abundantly to purified mannose-capped(Man) LAM from M tuberculosis,but not to uncapped LAM from M smegmatis . Fifteen to 45%of CD patients but only 0%-6% of controls were seropositive against different mycobacterial antigens. Anti-mycobacterial IgG correlated with ASCA(r = 0.37-0.64;P = 0.003-P < 0.001). ASCA-positivity and deficiency for mannan-binding lectin synergistically associated with anti-mycobacterial IgG. In some patients,anti-mycobacterial antibodies represent cross-reactive ASCA. Vice-versa,the predominant fraction of ASCA did not cross-react with mycobacteria. Finally,fistulizing disease associated with antibodies against M avium,M smegmatis and MAP(P = 0.024,0.004 and 0.045,respectively). CONCLUSION:Similar to ASCA,seroreactivity against mycobacteria may define CD patients with complicated disease and a predisposition for immune responses against ubiquitous antigens. While in some patients anti-mycobacterial antibodies strongly cross-react with yeast mannan;these cross-reactive antibodies only represent a minor fraction of total ASCA. Thus,mycobacterial infection unlikely plays a role in ASCA induction.

Managing stress granule disassembly with ubiquitin and its cousin

Recently,Maxwell et al.1 revealed a critical function of ubiquitylation in stress granule(SG)disassembly upon recovery from heat stress.Organisms are continuously exposed to endogenous or environmental stress.Genotoxic stress endangers DNA integrity,whereas proteotoxic stress causes an imbalance in protein homeostasis(proteostasis).Genotoxic insults activate DNA damage response pathways that halt the cell-cycle progression and initiate DNA repair.Protein quality control(PQC)systems in turn safeguard the integrity of the proteome and prepare for the restart of cellular activities upon stress release.Both genome and proteome integrity pathways are orchestrated by ubiquitin signaling and the ubiquitin-proteasome system(UPS).

斯图加特市图书馆

此项目选址在市中心一个略带坡度的区域，位于斯图加特欧洲区总规划图划定区域的中心地带。这个位于城市盆地内的区域南起斯图加特火车总站，北至北部边境的海尔布隆大街。建成之后，位于Mailander Platz的斯图加特市图书馆由于其独有的设计与规模将会带动周边的发展，未来新的市中心将在此形成规模。它全新的面貌，以浅灰色清水混凝土结构的外墙和边长达45米的立方体磨砂玻璃砖特点呈现，无不向人们宣告了它的存在。