280 research outputs found
Biological properties of the BCL-2 family protein BCL-RAMBO, which regulates apoptosis, mitochondrial fragmentation, and mitophagy
Mitochondria play an essential role in the regulation of cellular stress responses, including cell death. Damaged mitochondria are removed by fission and fusion cycles and mitophagy, which counteract cell death. BCL-2 family proteins possess one to four BCL-2 homology domains and regulate apoptosis signaling at mitochondria. BCL-RAMBO, also known as BCL2-like 13 (BCL2L13), was initially identified as one of the BCL-2 family proteins inducing apoptosis. Mitophagy receptors recruit the ATG8 family proteins MAP1LC3/GABARAP via the MAP1LC3-interacting region (LIR) motif to initiate mitophagy. In addition to apoptosis, BCL-RAMBO has recently been identified as a mitophagy receptor that possesses the LIR motif and regulates mitochondrial fragmentation and mitophagy. In the 20 years since its discovery, many important findings on BCL-RAMBO have been increasingly reported. The biological properties of BCL-RAMBO are reviewed herein
Revisiting the Rist diagram for predicting operating conditions in blast furnaces with multiple injections
Background: The Rist diagram is useful for predicting changes in blast furnaces when the operating conditions are modified. In this paper, we revisit this methodology to provide a general model with additions and corrections. The reason for this is to study a new concept proposal that combines oxygen blast furnaces with Power to Gas technology. The latter produces synthetic methane by using renewable electricity and CO2 to partly replace the fossil input in the blast furnace. Carbon is thus continuously recycled in a closed loop and geological storage is avoided. Methods: The new model is validated with three data sets corresponding to (1) an air-blown blast furnace without auxiliary injections, (2) an air-blown blast furnace with pulverized coal injection and (3) an oxygen blast furnace with top gas recycling and pulverized coal injection. The error is below 8% in all cases. Results: Assuming a 280 tHM/h oxygen blast furnace that produces 1154 kgCO2/tHM, we can reduce the CO2 emissions between 6.1% and 7.4% by coupling a 150 MW Power to Gas plant. This produces 21.8 kg/tHM of synthetic methane that replaces 22.8 kg/tHM of coke or 30.2 kg/tHM of coal. The gross energy penalization of the CO2 avoidance is 27.1 MJ/kgCO2 when coke is replaced and 22.4 MJ/kgCO2 when coal is replaced. Considering the energy content of the saved fossil fuel, and the electricity no longer consumed in the air separation unit thanks to the O2 coming from the electrolyzer, the net energy penalizations are 23.1 MJ/kgCO2 and 17.9 MJ/kgCO2, respectively. Discussion: The proposed integration has energy penalizations greater than conventional amine carbon capture (typically 3.7 – 4.8 MJ/kgCO2), but in return it could reduce the economic costs thanks to diminishing the coke/coal consumption, reducing the electricity consumption in the air separation unit, and eliminating the requirement of geological storage
Limits on the integration of power to gas with blast furnace ironmaking
This article compares 16 Power to Gas integrations for blast furnace ironmaking by using 17 key performance indicators. The study includes 4 types of PtG (PtH2, PtSNG using pure CO2, PtSNG using treated BFG, and PtSNG using BFG), two types of blast furnaces (air-blown and oxygen) and two types of fossil replacement (coal or coke). The blast furnaces are modelled using the Rist diagram, validated with literature data (<2% deviation). For most cases, the decrease in total CO2 emissions is around 150–215 kgCO2/tHM per MW/(tHM/h) of electrolysis. The energy penalty (in terms of electricity consumption) was found to be mostly independent on the size of the PtG plant, but greatly dependent on the type of integration (10.1–20.6 MJ/kgCO2). If significant CO2 reductions are aimed, self-sufficiency in electricity consumption will not be achieved. In practice, the maximum PtG capacity to install is limited by the decrease in the flame temperature. In this context, the PtSNG integration consuming treated BFG, applied to OBF for coal replacement, provides the best results. Assuming a 500 tHM/h blast furnace, the PtG capacity of this concept could be as large as 490 MW and avoid up to 21% of the CO2 emissions
Optimal labor income taxation and social security programs when private savings are unobservable
Modifications on the hydrogen bond network by mutations of Escherichia coli copper efflux oxidase affect the process of proton transfer to dioxygen leading to alterations of enzymatic activities
CueO has a branched hydrogen bond network leading from the exterior of the protein molecule to the trinuclear copper center. This network transports protons in the four-electron reduction of dioxygen. We replaced the acidic Glu506 and Asp507 residues with the charged and uncharged amino acid residues. Peculiar changes in the enzyme activity of the mutants relative to the native enzyme indicate that an acidic amino acid residue at position 506 is essential for effective proton transport. The Ala mutation resulted in the formation of a compensatory hydrogen bond network with one or two extra water molecules. On the other hand, the Ile mutation resulted in the complete shutdown of the hydrogen bond network leading to loss of enzymatic activities of CueO. In contrast, the hydrogen bond network without the proton transport function was constructed by the Gln mutation. These results exerted on the hydrogen bond network in CueO are discussed in comparison with proton transfers in cytochrome oxidase. © 2012 Elsevier Inc
A novel resting form of the trinuclear copper center in the double mutant of a multicopper oxidase, CueO, Cys500Ser/Glu506Ala
A multicopper oxidase, CueO was doubly mutated at its type I copper ligand, Cys500 and an acidic amino acid residue located in the proton transfer pathway, Glu506, to Ser and Ala, respectively. Cys500Ser/Glu506Ala was mainly in a novel resting form to afford the absorption band at ca. 400. nm and an EPR signal with a highly anisotropic character derived from type III copper. However, Cys500Ser/Glu506Ala gave the same reaction intermediate (peroxide intermediate) as that from Cys500Ser and Cys500Ser/Glu506Gln. © 2015 Elsevier Inc.Embargo Period 24 month
A novel resting form of the trinuclear copper center in the double mutant of a multicopper oxidase, CueO, Cys500Ser/Glu506Ala
Advanced Dry Gas Seal By The Dynamic Ion Beam Mixing Technique.
LecturePg. 39-48Ductile materials have been used for dry gas seal mating rings to
replace conventional sintered materials that have experienced
occasional brittle fracture. The ductile materials require a coating
to make them suitable for dry gas seal designs.
This paper describes the dynamic ion beam mixing (DM)
technique as an improvement in coating technology. Excellent
tribological properties of thin titanium nitride (TiN) films formed
by the dynamic ion beam mixing technique (DM/TiN) are
demonstrated. Further, performance of a dry gas seal provided with
a mating ring comprising a martensitic stainless steel substrate,
having a DM/TiN coating formed thereon, is demonstrated, while
making a comparison with the performance of a dry gas seal
utilizing conventional materials. Considerations necessary for
designing the ductile mating ring, its durability under abnormal
and severe conditions, testing of the DM coating, and results of
field experience are also discussed, together with problems
accompanying the use of ductile materials
Replacement of cisplatin with nedaplatin in a definitive 5-fluorouracil/cisplatin-based chemoradiotherapy in Japanese patients with esophageal squamous cell carcinoma
Objective: The effects of replacing cisplatin (CDDP) with cis-diammineglycolatoplatinum (nedaplatin, NDP), a second-generation platinum complex, on the pharmacokinetics of 5-fluorouracil (5-FU) were investigated in Japanese patients with esophageal squamous cell carcinoma, who were treated with a definitive 5-FU/CDDP-based chemoradiotherapy
Caspase Activation Is Required for T Cell Proliferation
Triggering of Fas (CD95) by its ligand (FasL) rapidly induces cell death via recruitment of the adaptor protein Fas-associated death domain (FADD), resulting in activation of a caspase cascade. It was thus surprising that T lymphocytes deficient in FADD were reported recently to be not only resistant to FasL-mediated apoptosis, but also defective in their proliferative capacity. This finding suggested potentially dual roles of cell growth and death for Fas and possibly other death receptors. We report here that CD3-induced proliferation and interleukin 2 production by human T cells are blocked by inhibitors of caspase activity. This is paralleled by rapid cleavage of caspase-8 after CD3 stimulation, but no detectable processing of caspase-3 during the same interval. The caspase contribution to T cell activation may occur via TCR-mediated upregulation of FasL, as Fas-Fc blocked T cell proliferation, whereas soluble FasL augmented CD3-induced proliferation. These findings extend the role of death receptors to the promotion of T cell growth in a caspase-dependent manner
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