Optimal Policy Combinations of Abatement Subsidy and Pollution Tax in Vertical Oligopolies

AbstractThis article investigates environmental regulations on eco-industry in vertical oligopolies, in which the upstream industry produces abatement goods reducing pollutants and the downstream industry produces consumption goods emitting pollutants. We devise the optimal combination of appropriate policy instruments and show that an optimal pollution tax should be used for the negative externality and output restrictions in final production, and an optimal abatement subsidy should incorporate the effect of upstream market restrictions on abatement activity. We also examine the welfare effect of the subsidy policy on the abatement technology in tax/subsidy combination

EFFECTS OF LIQUID SWIRLING ON GAS-TO-LIQUID MASS TRANSFER IN THREE-PHASE FLUIDIZED BEDS

The swirling flow mode of liquid phase was adopted to promote the gas-to-liquid mass transfer in three-phase(gas-liquid-solid) fluidized beds. Effects of gas(0.01-0.09m/s) and liquid(0.035-0.172m/s) velocities, particle size(1.7-6.0mm) and swirling ratio of liquid phase(0-0.5) on the volumetric gas-to-liquid mass transfer coefficient in the bed were examined. The mass transfer coefficient increased up to 70% by adjusting the swirling flow of liquid phase, especially when the gas velocity is relatively low range. The value of gas-to-liquid mass transfer coefficient was well correlated in terms of dimensionless groups which were derived from the dimensional analysis on the mass transfer system

Visual Genome-Wide RNAi Screening to Identify Human Host Factors Required for Trypanosoma cruzi Infection

The protozoan parasite Trypanosoma cruzi is the etiologic agent of Chagas disease, a neglected tropical infection that affects millions of people in the Americas. Current chemotherapy relies on only two drugs that have limited efficacy and considerable side effects. Therefore, the development of new and more effective drugs is of paramount importance. Although some host cellular factors that play a role in T. cruzi infection have been uncovered, the molecular requirements for intracellular parasite growth and persistence are still not well understood. To further study these host-parasite interactions and identify human host factors required for T. cruzi infection, we performed a genome-wide RNAi screen using cellular microarrays of a printed siRNA library that spanned the whole human genome. The screening was reproduced 6 times and a customized algorithm was used to select as hits those genes whose silencing visually impaired parasite infection. The 162 strongest hits were subjected to a secondary screening and subsequently validated in two different cell lines. Among the fourteen hits confirmed, we recognized some cellular membrane proteins that might function as cell receptors for parasite entry and others that may be related to calcium release triggered by parasites during cell invasion. In addition, two of the hits are related to the TGF-beta signaling pathway, whose inhibition is already known to diminish levels of T. cruzi infection. This study represents a significant step toward unveiling the key molecular requirements for host cell invasion and revealing new potential targets for antiparasitic therapy

Rational understanding of substituent effects on multi carbazole thermally activated delayed fluorescence emitters

Multi-carbazole thermally activated delayed fluorescence (TADF) molecules are promising emitters due to their fast reverse intersystem crossing (RISC) rate, and high device efficiency. They are composed of a benzonitrile acceptor and four or five carbazole donors or other functional groups that are connected to the acceptor. Since multiple moieties can be attached to benzonitrile, modification of the carbazole donors or other functional groups of multi-carbazole TADF molecules is facile. In addition, these modifications largely affect the emission spectrum, RISC rate, and device efficiency, which has Led to the development of various multi-carbazole TADF molecules and OLEDs based on them. Still, the effect of the modification of functional groups attached to the acceptor core has not been clearly investigated due to the complicated excited states of the multi-carbazole TADF molecules. Herein, we report two novel multi-carbazole TADF molecules developed by ortho-biphenyl and ortho-indolocarbazole substitutions of a multi-carbazole TADF molecule based on a benzonitrile backbone. The new TADF molecules, 4CzBN-BP and 4CzBN-ICz, comprise four carbazole donors, a benzonitrile acceptor core, and an ortho-biphenyl/indolocarbazole triplet scaffold. The devices based on 4CzBN-BP and 4CzBN-ICz showed maximum external quantum efficiencies (EQEs) of 12.5% and 4.2%, which were improved and decreased values, respectively, from the 10.9% of the 4CzBN device. To investigate the effect of substitutions on the excited-state dynamics and photophysical properties of the TADF molecule, we performed various photoluminescence measurements along with time-dependent density functional theory (TD-DFT) calculations. Based on comprehensive experimental and theoretical investigations, we found that not only the local triplet state of the triplet scaffold but also the local singlet state and the energy transfer to the charge-transfer singlet state of the TADF molecule are critical to the TADF emission process.11Nsciescopu

Development of a cell-defined siRNA microarray for analysis of gene function in human bone marrow stromal cells

Small interfering RNA (siRNA) screening approaches have provided useful tools for the validation of genetic functions; however, image-based siRNA screening using multiwell plates requires large numbers of cells and time, which could be the barrier in application for gene mechanisms study using human adult cells. Therefore, we developed the advanced method with the cell-defined siRNA microarray (CDSM), for functional analysis of genes in small scale within slide glass using human bone marrow stromal cells (hBMSCs). We designed cell spot system with biomaterials (sucrose, gelatin, poly-l-lysine and matrigel) to control the attachment of hBMSCs inside spot area on three-dimensional (3D) hydrogel-coated slides. The p65 expression was used as a validation standard which described our previous report. For the optimization of siRNA mixture, first, we detected five kinds of commercialized reagent (Lipofectamine 2000, RNAi-Max, Metafectine, Metafectine Pro, TurboFectin 8.0) via validation. Then, according to quantification of p65 expression, we selected 2 μl of RNAi-Max as the most effective reagent condition on our system. Using same validation standard, we optimized sucrose and gelatin concentration (80 mM and 0.13%), respectively. Next, we performed titration of siRNA quantity (2.66–5.55 μM) by reverse transfection time (24 h, 48 h, 72 h) and confirmed 3.75 μM siRNA concentration and 48 h as the best condition. To sum up the process for optimized CDSM, 3 μl of 20 μM siRNA (3.75 μM) was transferred to the 384-well V-bottom plate containing 2 μl of dH2O and 2 μl of 0.6 M sucrose (80 mM). Then, 2 μl of RNAi-Max was added and incubated for 20 min at room temperature after mixing gently and centrifugation shortly. Five microliters of gelatin (0.26%) and 2 μl of growth factor reduced phenol red-free matrigel (12.5%) were added and mixed by pipetting gently. Finally, optimized siRNA mixture was printed on 3D hydrogel-coated slides and cell-defined attachment and siRNA reverse transfection were induced. The efficiency of this CDSM was verified using three siRNAs (targeting p65, Slug, and N-cadherin), with persistent gene silencing for 5 days. We obtained the significant and reliable data with effective knock-down in our condition, and suggested our method as the qualitatively improved siRNA microarray screening method for hBMSCs