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In the face of environmental problems, the energy industry needs to convert energy sources into clean energy, but the technological maturity of renewable energy such as solar and wind power is not high enough, so each country is implementing expansion and dissemination policies based on various systems. The most representative energy policy, renewable energy certificate (REC) transaction system, based on the renewable portfolio standard (RPS), is a policy to supplement the economic feasibility of renewable generations until the technological maturity of them is completed, and is characterized by giving proper weights to each sources. TEG, a power generation source that utilizes waste pressure in the process of decompressing high-pressure gas, is one of the new renewable power candidates in the spotlight in terms of high eco-friendliness and energy recovery. In this paper, the economic and policy factors are evaluated to calculate the REC multipliers for new types of power sources. In particular, it is estimated based on the power generation and electricity sales performance data collected through the operation of the 300 kW TEG operating at the Gimhae decompression facility in Korea.

B cells play a major role in regulating disease incidence through various factors, including spleen tyrosine kinase (Syk), which transmits signals to all hematopoietic lineage cells. Hypoxia-inducible factor (HIF)-1α accumulates under hypoxic conditions, which is also oxidative stress to induce nuclear factor (erythroid-derived 2)-like 2 (Nrf2) responsible for gene expression of antioxidant enzymes. In the present study, we investigated whether B cells are regulated by crosstalk of HIF-1α and Nrf2 via reactive oxygen species (ROS)-mediated Syk activation. When B cells were incubated under hypoxic conditions, Syk phosphorylation, HIF-1α, and Nrf2 levels were increased. Hypoxia-inducible results were consistent with CoCl2 treatment, which mimics hypoxic conditions. Cell viability was reduced by the Syk inhibitor BAY 61-3606. Increased Nrf2 levels due to hypoxia or CoCl2 were inhibited by treatment with a HIF inhibitor. Hypoxia- or CoCl2-induced ROS increased HIF-1α and Nrf2 levels, which were attenuated by treatment with N-acetyl-L-cysteine (NAC), a ROS scavenger. HIF-1α levels were reduced in doxycycline-treated shNrf2 cells. Clobetasol propionate, a Nrf2 inhibitor, also inhibited HIF-1α levels induced by hypoxia or CoCl2. ROS-mediated Syk phosphorylation at tyrosine 525/526 was confirmed by treatment with H2O2, hypoxia, and CoCl2, and attenuated with NAC treatment. Inhibition of Syk phosphorylation by BAY 61-3606 is consistent with a decrease in protein HIF-1α and Nrf2 levels. Taken together, HIF-1α levels might control Nrf2 levels and vice versa, and could be associated with Syk phosphorylation in B cells. The results indicate that B cells could be regulated by crosstalk of HIF-1α and Nrf2 through ROS-mediated Syk activation.

Cell survival is facilitated by the maintenance of mitochondrial membrane potential (MMP). B cell activating factor (BAFF) plays a role in survival, differentiation, and maturation of B cells. In the present study, we examined whether BAFF could attenuate oxidative stress-induced B cell death by the regulation of MMP collapse via spleen tyrosine kinase (Syk) activation using WiL2-NS human B lymphoblast cells. BAFF binds to receptors on WiL2-NS cells. When the cells were incubated in serum-deprived conditions with 1% fetal bovine serum (FBS), BAFF reduced the percentage of dead cells as determined through trypan blue staining and caspase 3 activity. BAFF also inhibited MMP collapse with 1% FBS, as indicated by a decrease in the number of cells with high-red fluorescence of MitoProbe™ JC-1 reagent or a decrease in the percentage of DiOC6-stained cells. Reactive oxygen species (ROS) production was reduced by incubation with BAFF in the presence of 10% or 1% FBS. BAFF inhibited MMP collapse, cell growth retardation, dead cell formation, and caspase 3 activation caused by treatment with H2O2. Syk phosphorylation on tyrosine (Y) 525/526 was increased in cells incubated with 1% FBS in the presence of BAFF than cells incubated with 1% FBS or BAFF alone. BAY61-3606, a Syk inhibitor reduced the effect of BAFF on MMP collapse, caspase 3 activation, cell growth retardation, and dead cell formation. Together, these data demonstrate that BAFF might attenuate oxidative stress-induced B cell death and growth retardation by the maintenance of MMP through Syk activation by Y525/526 phosphorylation. Therefore, BAFF and Syk might be therapeutic targets in the pathogenesis of B cell-associated diseases such as autoimmune disease.

We investigated the hemodynamic and mortality effects of continuous ketamine infusion in critically ill pediatric patients. We conducted a retrospective cohort study in a tertiary pediatric intensive care unit (PICU). Patients who used continuous sedative from 2015 to 2017 for 24 hours or more were included. We compared blood pressure, heart and respiratory rates, vasogenic medications, and sedation and pain scores for 12 hours before and after initiation of continuous ketamine. The mortality rates for continuous ketamine and Non-ketamine groups were compared by multivariate logistic regression. A total of 240 patients used continuous sedation, and 82 used continuous ketamine. The median infusion rate of ketamine was 8.1 mcg/kg/min, and the median duration was 6 days. Heart rates (138 vs. 135 beat/minute, P = .033) and respiratory rates (31 vs. 25 respiration/minute, P = .001) decreased, but blood pressure (99.9 vs. 101.1 mm Hg, P = .124) and vasogenic medications did not change after ketamine infusion. Continuous ketamine was not a significant risk factor for mortality (hazard ratio 1.352, confidence interval 0.458-3.996). Continous ketamine could be used in PICU without hemodynamic instability. Further studies in randomized controlled design about the effects of continuous ketamine infusion on hemodynamic changes, sedation, and mortality are required.

Nonylphenol (NP) as well-known "endocrine disrupter" influences sexual and reproductive development. Here, we investigated the effect of NP on M1-/M2-type macrophages and their role in lipopolysaccharide (LPS)-induced sepsis. Polarized macrophages of M1- and M2-types were obtained by the treatment with LPS and interleukin-4 (IL-4) to bone marrow-derived macrophages (BMDM), respectively. Coincubation of M1-macrophages with NP decreased COX-2, iNOS, IL-6, and TNF-α expression but no changes were detected in the production of nitric oxide (NO). Survival probability of LPS-induced sepsis mice was enhanced by the injection of NP-treated BMDM as compared to the injection of NP-untreated control BMDM. In the meanwhile, the expression of arginase 1(Arg1), a marker for M2-polarized macrophages was increased by the stimulation with LPS in BMDM. Arg1 expression was also enhanced by the treatment with IL-4 in BMDM, which was reduced by the coincubation with NP. Survival probability of LPS-induced sepsis mice was decreased by the injection of BMDM treated with IL-4 and NP as compared to the injection of IL-4-treated BMDM. It suggests that NP might inhibit macrophage function and the polarization to M2-macrophages. Taken together, data demonstrate that NP could differently affect immune responses of polarized macrophages resulted in the modulation of LPS-induced sepsis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 2081-2089, 2016.

Autoimmune rheumatic lesions are often characterised by the immune cell recruitment including B lymphocytes and the presence of reactive oxygen species (ROS), which increase antioxidant gene transcription via nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Spleen tyrosine kinase (Syk) has a major role in the signal transmission of all haematopoietic lineage cells including B/T cells, mast cells, and macrophages. In this study, we investigated whether B cell survival is regulated by Nrf2 via ROS-mediated Syk activation in WiL2-NS human B lymphoblast cells. When WiL2-NS cells were incubated with 1% foetal bovine serum (FBS), the survival rate and mitochondrial membrane potential (MMP) were reduced. In addition, 1% FBS increased caspase 3 activity, cytochrome C release, nuclear localisation of Nrf2, and ROS production. N-acetylcysteine attenuated ROS production and nuclear translocation of Nrf2. It also inhibited cell death, caspase 3 activation, MMP collapse, and cytochrome C release. Results from the 1% FBS treatment were consistent with those of H

When defective or absent, Werner syndrome protein (WRN) causes a genetic premature aging disorder called Werner syndrome. Several studies have reported that defects in WRN function are responsible for not only progeria syndrome but also genomic instability via the deregulation of DNA repair, replication, recombination, and telomere stability. Given the importance of WRN in the repair process, we herein investigated the potential role of WRN in drug response by evaluating the DNA repair following exposure to cisplatin in human cancer cell lines. We found that the down-regulation of SIRT1 and inhibition of SIRT1 deacetylase activity blocked the translocation of WRN from the nucleolus to the nucleoplasm in response to genotoxic stresses. In addition, cells expressing low levels of WRN responded favorably to cisplatin, whereas cells expressing high levels responded poorly to cisplatin. The forced expression of WRN protein in chemosensitive cells resulted in an approximately two-fold increase in cell viability in response to cisplatin compared with vector controls and promoted DNA repair, while WRN-deficient cells accumulate unrepaired double-strand breaks following cisplatin exposure. These results suggest that WRN is regulated by SIRT1 and increased expression of WRN might be one of the determinants for the development of chemotherapeutic drug resistance.

Two small molecules with acceptor–donor–acceptor (A–D–A) structures, i.e. SN(BTTh2)2 and SN(BTAOTh2)2, denoted as J and K, respectively, containing an electron rich planar S,N-heteropentacene as the central core flanked with alkoxy substituted and un-substituted benzothiadiazole (BT) and end capped with hexyl-substituted bi-thiophene units, were designed and synthesized. Optical and electrochemical investigation of these two small molecules reveals that these compounds possess low optical bandgaps and broader absorption profiles to harvest solar photons, as well as suitable electrochemical molecular energy levels for application as donors in bulk heterojunction organic solar cells. The photovoltaic properties of these two small molecules as donors and PC71BM as the acceptor in solution processed bulk heterojunction cells were investigated. Devices based on cast J : PC71BM and K : PC71BM active layers showed power conversion efficiencies (PCE) of 1.96% and 1.57%, respectively; these efficiencies improved to 6.02% and 5.06% when the active layers were subjected to two steps annealing (TSA), i.e. combined thermal annealing followed by solvent vapor annealing. The increase in PCE was due to the enhancement of both the short circuit current (Jsc) and fill factor (FF) due to the enhancement of the light harvesting ability of the active layer, better phase separation between the small molecules and PC71BM, and more balanced charge transport induced by the TSA treatment.

Phthalates are widely used as plasticizers that influence sexual and reproductive development. Here, we investigated whether di-(2-ethylhexyl) phthalate (DEHP) affects macrophage polarization that are associated with tumor initiation and progression. No changes were observed in LPS- or ConA-stimulated in vitro spleen B or T cell proliferation for 48 h, respectively. In contrast, macrophage functions were inhibited in response to DEHP for 12 h as judged by LPS-induced H2O2 and NO production and zymosan A-mediated phagocytosis. When six weeks old male mice were pre-exposed to 4.0 mg/kg DEHP for 21 days before the injection of B16F10 melanoma cells and post-exposed to 4.0 mg/kg DEHP for 7 days, tumor nodule formation and the changes in tumor volume were higher than those in control group. Furthermore, when male mice were intraperitoneally pretreated with DEHP for 3 or 4 weeks and peritoneal exudate cells (PECs) or bone marrow-derived macrophages (BMDMs) were incubated with lipopolysaccharide (LPS), the expression of COX-2, TNF-α, and IL-6 was reduced in DEHP-pretreated cells as compared with that in LPS-stimulated control cells. While the production of nitric oxide (NO) for 18 h was reduced by LPS-stimulated PECs and M1-type BMDMs, IL-4 expression was enhanced in LPS-stimulated BMDMs. When BMDMs were incubated with IL-4 for 30 h, arginase 1 for M2-type macrophages was increased in transcriptional and translational level. Data implicate that macrophages were differentially polarized by DEHP treatment, which reduced M1-polarzation but enhanced M2-polarization. Taken together, these data demonstrate that DEHP could affect in vivo immune responses of macrophages, leading to the suppression of their tumor-preventing ability. This suggests that individuals at high risk for tumor incidence should avoid long-term exposure to various kind of phthalate including DEHP.

Two symmetrical star-shaped hole transporting materials (HTMs), i.e. FA-MeOPh and TPA-MeOPh with a fused triphenylamine or triphenylamine core and diphenylethenyl side arms were synthesized. FA-MeOPh showed a strong molar absorption coefficient and a red-shifted absorption compared with TPA-MeOPh because of its planar configuration. The power conversion efficiency (PCE) of the perovskite solar cells based on FA-MeOPh and TPA-MeOPh is about 11.86% and 10.79%, in which the efficiency of former is comparable to that (12.75%) of spiro-OMeTAD based cell. The high photocurrent (18.39 mA cm(-2)) of FA-MeOPh based solar cell relative to TPA-MeOPh based one may be attributable to the enhanced absorption in the near-IR region for mp-TiO2/CH3NH3PbI3/HTM based cell. The high mobility and low series resistance of mp-TiO2/CH3NH3PbI3/FA-MeOPh based cell led to the high fill factor (0.698) of FA-MeOPh based solar cell relative to TPA-MeOPh based one (0.627). In addition, the FA-MeOPh based cell showed a relative stability under light soaking for 250 h. The high efficiency, relative stability, synthetically simple and inexpensive materials as the HTMs hold promise to replace the expensive spiro-OMeTAD.

Building maintenance is closely related to the performance and sustainability of buildings. However, existing approaches to maintenance are limited in terms of estimating required repairs. Therefore, this study proposes a case-based reasoning (CBR)-based model for estimating the time when the first repair will be needed after the completion of construction, even in phases where maintenance-related information is scarce. CBR and fuzzy-analytic hierarchy process (AHP) were employed as research methodologies. A database was established by collecting 257 cases related to maintenance of apartment buildings, and attributes were extracted through literature reviews and expert interviews. Then, attributes were weighted by fuzzy-AHP and case similarities were computed by measuring the Euclidean distance. Similar cases were retrieved based on similarity scores. The model was validated via a comparison of 20 randomly selected test cases with the output of retrieved cases. The results showed that the average case similarities of 3-, 5-, 7-, and 10-nearest neighbors (NN) were 98.05%, 97.86%, 97.73%, and 97.59%, respectively, and mean absolute percentage errors for 3-, 5-, 7-, and 10-NN were mostly lower than 20%, confirming the applicability of the proposed model. The proposed method will help in the preliminary estimation of the repair time of building components.

Trichostatin A (TSA) is an anticancer drug that inhibits histone deacetylases (HDACs). Hypoxia-inducible factor 1 (HIF-1) participates in tumor angiogenesis by upregulating target genes, such as vascular endothelial growth factor (VEGF). In the present study, we investigated whether TSA treatment increases HIF-1α stabilization via acetylation under normoxic conditions, which would lead to VEGF upregulation and resistance to anticancer drugs. TSA enhanced total HIF-1α and VEGF-HRE reporter activity under normoxic conditions. When cells were transfected with GFP-HIF-1α, treatment with TSA increased the number of green fluorescence protein (GFP)-positive cells. TSA also enhanced the nuclear translocation of HIF-1α protein, as assessed by immunoblotting and as evidenced by increased nuclear localization of GFP-HIF-1α. An increase in the interaction between HIF-1α and the VEGF promoter, which was assessed by a chromatin immunoprecipitation (ChIP) assay, led to activation of the VEGF promoter. TSA acetylated HIF-1α at lysine (K) 674, which led to an increase in TSA-induced VEGF-HRE reporter activity. In addition, TSA-mediated cell death was reduced by the overexpression of HIF-1α but it was rescued by transfection with a HIF-1α mutant (K674R). These data demonstrate that HIF-1α may be stabilized and translocated into the nucleus for the activation of VEGF promoter by TSA-mediated acetylation at K674 under normoxic conditions. These findings suggest that HIF-1α acetylation may lead to resistance to anticancer therapeutics, such as HDAC inhibitors, including TSA.

Nonylphenol (NP) as well-known "endocrine disrupter" influences sexual and reproductive development. Here, we investigated the effect of NP on M1-/M2-type macrophages and their role in lipopolysaccharide (LPS)-induced sepsis. Polarized macrophages of M1- and M2-types were obtained by the treatment with LPS and interleukin-4 (IL-4) to bone marrow-derived macrophages (BMDM), respectively. Coincubation of M1-macrophages with NP decreased COX-2, iNOS, IL-6, and TNF-α expression but no changes were detected in the production of nitric oxide (NO). Survival probability of LPS-induced sepsis mice was enhanced by the injection of NP-treated BMDM as compared to the injection of NP-untreated control BMDM. In the meanwhile, the expression of arginase 1(Arg1), a marker for M2-polarized macrophages was increased by the stimulation with LPS in BMDM. Arg1 expression was also enhanced by the treatment with IL-4 in BMDM, which was reduced by the coincubation with NP. Survival probability of LPS-induced sepsis mice was decreased by the injection of BMDM treated with IL-4 and NP as compared to the injection of IL-4-treated BMDM. It suggests that NP might inhibit macrophage function and the polarization to M2-macrophages. Taken together, data demonstrate that NP could differently affect immune responses of polarized macrophages resulted in the modulation of LPS-induced sepsis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 2081-2089, 2016.

Patterns of adverse drug reactions (ADRs) in the medical intensive care unit (MICU) were analysed, and signals for detecting ADRs were developed from the analysis. A retrospective study was conducted in MICU wards at a tertiary care teaching hospital in Seoul, Korea. The areas included one general MICU and one cancer centre MICU. Two pharmacists evaluated ADRs in terms of length of stay, causality, severity, preventability, types, related organs, and incidence. Differences in ADR perception rates between physicians and pharmacists were also evaluated. ADR cases detected through the evaluation were reviewed to develop specific alerting signals for ICU ADRs. The study group included 346 patients admitted to the ICU over 4 months. The overall incidence of ADRs was 32%. ICU length of stay is closely related to ADRs (p = 0.014). Most ADR cases were mild, temporary, and harmful to the patient. Twenty percent of ADRs were preventable, and 74% were type A. Of the ADRs, 70% were noted by physicians; 80% required intervention. The most commonly implicated drug was amphotericin B, and the clinical presentation was a haematologic reaction. Data on the time required for pharmacists to identify ADRs indicated that they were not slower than physicians. Six signals for early detection of the ADRs were developed. The overall ADR incidence in the MICU was about one-third, and the length of stay of the ADR group was longer than that of those without this experience. Automated signal generation was developed. It seemed to be a valuable tool for faster and more efficient patient management, and possibly prevention of ADRs. A future study should scientifically evaluate the clinical relevance of this tool.

The Caenorhabditis elegans Werner syndrome protein, WRN-1, a member of the RecQ helicase family, has a 3'-5' DNA helicase activity. Worms with defective wrn-1 exhibit premature aging phenotypes and an increased level of genome instability. In response to DNA damage, WRN-1 participates in the initial stages of checkpoint activation in concert with C. elegans replication protein A (RPA-1). WRN-1 helicase is stimulated by RPA-1 on long DNA duplex substrates. However, the mechanism by which RPA-1 stimulates DNA unwinding and the function of the WRN-1-RPA-1 interaction are not clearly understood. We have found that WRN-1 physically interacts with two RPA-1 subunits, CeRPA73 and CeRPA32; however, full-length WRN-1 helicase activity is stimulated by only the CeRPA73 subunit, while the WRN-1(162-1056) fragment that harbors the helicase activity requires both the CeRPA73 and CeRPA32 subunits for the stimulation. We also found that the CeRPA73(1-464) fragment can stimulate WRN-1 helicase activity and that residues 335-464 of CeRPA73 are important for physical interaction with WRN-1. Because CeRPA73 and the CeRPA73(1-464) fragment are able to bind single-stranded DNA (ssDNA), the stimulation of WRN-1 helicase by RPA-1 is most likely due to the ssDNA binding activity of CeRPA73 and the direct interaction of WRN-1 and CeRPA73.

Background Curcumin, a major component of curry powder, which is a natural polyphenol product extracted from rhizoma curcumae longae, interacts with a specific binding site on microtubules. Vinblastine is an antitumor drug that induces microtubule depolymerization. Purpose We investigated whether curcumin influences the antitumor effect of vinblastine in HeLa human cervical cancer cells. Study design Changes in microtubule filaments were visualized by immuno-staining. Cell death was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) or water-soluble tetrazolium(WST) assay. Apoptotic cell formation was assessed by flow cytometry after staining cells with propidium iodide(PI) and/or Annexin V or with 6-diamidino-2-phenylindole(DAPI). Reactive oxygen species(ROS) were also measured by flow cytometry using dichloro-dihydro-fluorescein diacetate(DCF-DA). JC-1 was used to determine mitochondrial membrane potential (MMP). Results When cells were pretreated with curcumin, microtubule filaments were disordered. Vinblastine-induced microtubule depolymerization and cell death were reduced in HeLa human cervical cancer cells pretreated with curcumin compared to the control. The decrease in cell death was much greater in cells pretreated with curcumin compared to cotreatment or post-treatment. DNA condensation by vinblastine was also decreased in curcumin-pretreated cells. Curcumin reduced ROS production by vinblastine. However, no changes in vinblastine-mediated microtubule depolymerization were detected upon N-acetylcysteine(NAC) treatment. In contrast, vinblastine-induced MMP collapse was inhibited by pretreatment with curcumin or NAC. These findings suggest that vinblastine-induced tumor cell death might be inhibited by curcumin via ROS-independent microtubule dynamics and ROS-dependent MMP collapse. It also suggests that microtubule dynamics could be necessary for the optimal antitumor activity of vinblastine. Our results suggest that patients treated with vinblastine should not consume curcumin.

Literally hundreds of scales have been developed to measure personality constructs relevant to consumer behavior, marketing, and organizational behavior issues. A key problem is that to our knowledge no theory or model has been developed that provides an organizational structure for understanding the relationships among these many scales. The present article has two goals. The first is to present the theoretical basis for the 3M Model of Motivation and Personality [Mowen JC. The 3M Model of Motivation and Personality: Theory and Empirical Applications to Consumer Behavior . Kluwer Academic Publishers, 2000.] and identify how the model works to organize personality constructs into a hierarchically ordered nomological net. In addition, the article illustrates the 3M Model approach via an empirical study that compares the trait antecedents of enduring dispositions to send and receive marketplace information of respondents in the United States and Korea.

The paper examines the effects of usage goal (i.e., hedonic versus utilitarian usage), whether the consumer is offered a discount or the ability to trade-in the old product, and tightwadism on the likelihood of replacing a still-functioning product. Supporting previous research, the results revealed that the likelihood of replacing a still-functioning product is higher when a trade-in is offered. As expected, however, this main effect was moderated by whether the good was purchased for utilitarian rather than hedonic purposes. If the purchase was for hedonic purchases, the likelihood of purchase was significantly lower when the promotion was a sale rather than a trade-in. However, the promotion type did not influence the purchase if it was for utilitarian purposes. Additionally, when the usage goal was for hedonic purposes, the likelihood of replacement was significantly lower for those high in tightwadism. In contrast, tightwadism did not influence the likelihood of replacement when the usage was for utilitarian purposes. Copyright © 2007 John Wiley & Sons, Ltd.

Novel symmetric oligomer hole transporting materials (HTMs) incorporating 3,4-ethylenedioxythiophene (EDOT) and 2,1,3-benzothiadiazole (BTD) cores have been synthesized and tested for high performance perovskite solar cells. A maximum energy conversion efficiency of 14.23% has been achieved by employing with the electron donating EDOT unit as the core, which is comparable to that of the traditional (14.55%).

DNA damage responses are important for the maintenance of genome stability and the survival of organisms. Such responses are activated in the presence of DNA damage and lead to cell cycle arrest, apoptosis, and DNA repair. In Caenorhabditis elegans, double-strand breaks induced by DNA damaging agents have been detected indirectly by antibodies against DSB recognizing proteins. In this study we used a comet assay to detect DNA strand breaks and to measure the elimination of DNA strand breaks in mitotic germline nuclei of C. elegans. We found that C. elegans brc-1 mutants were more sensitive to ionizing radiation and camptothecin than the N2 wild-type strain and repaired DNA strand breaks less efficiently than N2. This study is the first demonstration of direct measurement of DNA strand breaks in mitotic germline nuclei of C. elegans. This newly developed assay can be applied to detect DNA strand breaks in different C. elegans mutants that are sensitive to DNA damaging agents.

Novel steric bulky hole transporting materials (HTMs) with two or four N,N-di(4-methoxyphenyl)aminophenyl units have been synthesized. When the EtheneTTPA was used as a hole transporting material in perovskite solar cell, the power conversion efficiency afforded 12.77 % under AM 1.5 G illumination, which is comparable to the widely used spiro-OMeTAD based solar cell (13.28 %).

The current research investigates how childhood wealth has perpetuating influences on directive and empowering leadership. With the data from 203 leaders at a health food company in Korea, we found...

Increasing global warming is recognized as the most critical issues encountered in this century. Therefore research target at solar energy harvesting is currently under extensive investigation. One promising technology would be organic solar cell, which is expected to dominate the low-cost market in the future. In the organic solar cell, numerous polymers have been used as light harvest. Due to the synthetic difficulty, molecular weight distribution, many research groups have expended endeavors to develop small molecules as the alternative sensitizers, which are easy to the synthesis. Recently, impressive photovoltaic performances have been reported on various well designed small molecules, showing promising efficiency in the range of 5~8.5%. Recently, we synthesized a new series of small molecules with thiophene perylene bisimide, benzothiadiazole, anthracene based chromophore and planar star-shaped unit. In this presentation, we want to report various different type of small molecules for efficient organic solar cells.