Enhanced Performance of Solution‐Processed TESPE‐ADT Thin‐Film Transistors

Chen, Liang&#x2010,Hsiang,Hu, Tarng&#x2010,Shiang,Huang, Peng&#x2010,Yi,Kim, Choongik,Yang, Ching&#x2010,Hao,Wang, Juin&#x2010,Jie,Yan, Jing&#x2010,Yi,Ho, Jia&#x2010,Chong,Lee, Cheng&#x2010,Chung,Chen WILEY‐VCH Verlag 2013 Chemphyschem Vol.14 No.12

<P><B>Abstract</B></P><P>A solution‐processed anthradithiophene derivative, 5,11‐bis(4‐triethylsilylphenylethynyl)anthradithiophene (TESPE‐ADT), is studied for use as the semiconducting material in thin‐film transistors (TFTs). To enhance the electrical performance of the devices, two different kinds of solution processing (spin‐coating and drop‐casting) on various gate dielectrics as well as additional post‐treatment are employed on thin films of TESPE‐ADT, and <I>p</I>‐channel OTFT transport with hole mobilities as high as ∼0.12 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> are achieved. The film morphologies and formed microstructures of the semiconductor films are characterized in terms of film processing conditions and are correlated with variations in device performance.</P>

Laser Raman detection of platelet as a non‐invasive approach for early and differential diagnosis of Alzheimer's disease

Chen, P.,Tian, Q.,Baek, S.J.,Shang, X.L.,Park, A.,Liu, Z.C.,Yao, X.Q.,Wang, J.Z.,Wang, X.H.,Cheng, Y.,Peng, J.,Shen, A.G.,Hu, J.M. WILEY‐VCH Verlag 2011 Laser physics letters Vol.8 No.7

<P><B>Abstract</B></P><P>Early and differential diagnosis of Alzheimer's disease (AD) is a problem that puzzled many doctors. Reliable markers in easy‐assembling samples are of considerable clinical diagnostic value. In this work, laser Raman spectroscopy (LRS) was developed a new method that potentially allows early and differential diagnosis of AD from the platelet sample. Raman spectra of platelets isolated from different ages of AD transgenic mice and non‐transgenic controls were collected and analyzed. Multilayer perceptron networks (MLP) classification method was used to classify spectra and establish the diagnostic models. For differential diagnosis, spectra of platelets isolated from AD, Parkinson’s disease (PD) and vascular dementia (VD) mice were also discriminated. Two notable spectral differences at 740 and 1654 cm<SUP>–1</SUP> were revealed in the mean spectrum of platelets isolated from AD transgenic mice and the controls. MLP displayed a powerful ability in the classifying of early, advanced AD and the control group, and in differential diagnosis of PD and advanced AD, as well as VD and advanced AD. The results suggest that platelet detecting by LRS coupled with MLP analysis appears to be an easy and accurate method for early and differential diagnosis of AD. This technique could be rapidly promoted from laboratory to the hospital. (© 2011 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA) (© 2011 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)</P>

Obovatol improves cognitive functions in animal models for Alzheimer’s disease

Choi, Dong&#x2010,Young,Lee, Jae Woong,Peng, Jin,Lee, Young Jung,Han, Jin&#x2010,Yi,Lee, Yeon Hee,Choi, Im Seop,Han, Sang Bae,Jung, Jae Kyung,Lee, Woong Soo,Lee, Seung&#x2010,Ho,Kwon, Byoung&#x2010,Mo Blackwell Publishing Ltd 2012 Journal of Neurochemistry Vol.120 No.6

<P><I>J. Neurochem.</I> (2012) <B>120</B>, 1048–1059.</P><P><B>Abstract</B></P><P>Etiology of Alzheimer’s disease (AD) is obscure, but neuroinflammation and accumulation of β‐amyloid (Aβ) are implicated in pathogenesis of AD. We have shown anti‐inflammatory and neurotrophic properties of obovatol, a biphenolic compound isolated from <I>Magnolia obovata</I>. In this study, we examined the effect of obovatol on cognitive deficits in two separate AD models: (i) mice that received intracerebroventricular (i.c.v.) infusion of Aβ<SUB>1–42</SUB> (2.0 μg/mouse) and (ii) Tg2576 mice‐expressing mutant human amyloid precursor protein (K670N, M671L). Injection of Aβ<SUB>1–42</SUB> into lateral ventricle caused memory impairments in the Morris water maze and passive avoidance tasks, being associated with neuroinflammation. Aβ<SUB>1–42</SUB>‐induced abnormality was significantly attenuated by administration of obovatol. When we analyzed with Tg2576 mice, long‐term treatment of obovatol (1 mg/kg/day for 3 months) significantly improved cognitive function. In parallel with the improvement, treatment suppressed astroglial activation, BACE1 expression and NF‐κB activity in the transgenic mice. Furthermore, obovatol potently inhibited fibrillation of Aβ<I>in vitro</I> in a dose‐dependent manner, as determined by Thioflavin T fluorescence and electron microscopic analysis. In conclusion, our data demonstrated that obovatol prevented memory impairments in experimental AD models, which could be attributable to amelioration of neuroinflammation and amyloidogenesis by inhibition of NF‐κB signaling pathway and anti‐fibrillogenic activity of obovatol.</P>

Enhancing dendritic cell vaccine potency by combining a <i>BAK/BAX</i> siRNA‐mediated antiapoptotic strategy to prolong dendritic cell life with an intracellular strategy to target antigen to lysosomal compartments

Kang, Tae Heung,Lee, Jin Hyup,Noh, Kyung Hee,Han, Hee Dong,Shin, Byung Cheol,Choi, Eun Young,Peng, Shiwen,Hung, Chien&#x2010,Fu,Wu, T.&#x2010,C.,Kim, Tae Woo Alan R. Liss, Inc 2007 International journal of cancer Vol.120 No.8

<P><B>Abstract</B></P><P>Dendritic cell (DC)‐based vaccines have become important in immunotherapeutics as a measure for generating antitumor immune responses. We have previously demonstrated that linkage of the antigen gene to a lysosomal targeting signal, a sorting signal of the lysosome‐associated membrane protein type 1 (LAMP‐1), enhances the potency of DC‐based vaccines. DCs have a limited life span, hindering their long‐term ability to prime antigen‐specific T cells. In this study, we attempted to further improve the potency of a DC vaccine that targets human papilloma virus 16 (HPV16) E7 to a lysosomal compartment (DC‐Sig/E7/LAMP‐1) by combining a strategy to prolong DC life. We show that small interfering RNA‐targeting Bak and Bax proteins can be used to allow transfected DCs to resist being killed by T cells. This is done by downregulating these proapoptotic proteins, which have been known as so‐called gate keepers in mitochondria‐mediated apoptosis. DCs expressing intact E7 or Sig/E7/LAMP‐1 became resistant to attack by CD8<SUP>+</SUP> T cells after transfection with <I>BAK/BAX</I> siRNA, leading to enhanced E7‐specific T cell activation <I>in vitro</I> and <I>in vivo</I>. More importantly, vaccination with E7‐presenting DCs transfected with <I>BAK/BAX</I> siRNA generated a strong therapeutic effect against an E7‐expressing tumor in vaccinated mice, compared with DCs transfected with control siRNA. Our data indicate that a combination of strategies to enhance intracellular Ag processing and to prolong DC life may offer a promising strategy for improving DC vaccine potency. © 2007 Wiley‐Liss, Inc.</P>

Microwave Absorption and Magnetic Properties of Cobalt Ferrites/Carbon Nanotubes Nanocomposites

B. B. Zhang,P. F. Wang,J. C. Xu,Y. B. Han,H. X. Jin,D. F. Jin,X. L. Peng,B. Hong,J. Li,J. Gong,H. L. Ge,Z. W. Zhu,X. Q. Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.5

Owing to the unique microstructure and the excellent dielectric properties, carbon nanotubes(CNTs) were decorated with CoFe2O4 nanoparticles to synthesize the CoFe2O4/CNTs nanocomposites by the solvothermal method. The phase structure, morphology, magnetic properties and microwave absorption performance of the as-prepared CoFe2O4/CNTs were characterized and discussed by X-ray diffraction (XRD), thermal gravity analysis (TGA), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). All results indicated that the diameter of CoFe2O4 nanoparticles decorating on the surface of CNTs increased with the solvothermal temperature. CoFe2O4/CNTs prepared at 180℃, 200℃ and 220℃ exhibited superparamagnetism, while the other samples presented ferromagnetism at room temperature. And with the increasing solvothermal temperature, the saturation magnetization and coercivity increased up to 72 emu/g and 2000 Oe for the sample prepared at 260℃ (S-26). And the reflection loss of CoFe2O4/CNTs nanocomposites increased with the solvothermal temperature up to -15.7 dB for S-26 with the bandwidth of 2.5 GHz.

Delayed Afterdepolarization in Intact Canine Sinoatrial Node as a Novel Mechanism for Atrial Arrhythmia

JOUNG, BOYOUNG,ZHANG, HONG,SHINOHARA, TETSUJI,MARUYAMA, MITSUNORI,HAN, SEONGWOOK,KIM, DAEHYEOK,CHOI, EUE&#x2010,KEUN,ON, YOUNG&#x2010,KEUN,LIN, SHIEN&#x2010,FONG,CHEN, PENG&#x2010,SHENG Blackwell Publishing Inc 2011 Journal of cardiovascular electrophysiology Vol.22 No.4

<P> <B>Delayed Afterdepolarization in Sinoatrial Node. <I>Introduction:</I></B> Recent evidence indicates that spontaneous sarcoplasmic reticulum Ca release and Na‐Ca exchanger current activation contribute to the sinoatrial node (SAN) automaticity. These findings suggest that SAN activity may share mechanisms that underlie both automaticity and triggered activity. The aim of this study is to test the hypothesis that spontaneous, nonvoltage gated, intracellular Ca (Ca<SUB>i</SUB>) elevation may induce delayed afterdepolarization (DAD) in intact SAN during isoproterenol infusion.</P><P> <B> <I>Methods and Results:</I> </B> We simultaneously mapped Ca<SUB>i</SUB> and membrane potential in 31 isolated Langendorff‐perfused canine right atriums (RA). Isoproterenol increased heart rate and late diastolic Ca<SUB>i</SUB> elevation (LDCAE) of the superior SAN, leading to consistent SAN automaticity in all 31 RAs. However, DAD‐like diastolic depolarizations (DD) were transiently observed in 4 RAs during isoproterenol infusion. These DAD‐like DDs were preceded by LDCAE, but did not trigger a full action potential. The LDCAE preceding DAD‐like DDs had smaller amplitude (0.41 ± 0.08 AU vs 0.48 ± 0.07 AU, P = 0.001) and less steep slopes (3.7 ± 1.3 AU/s vs 4.8 ± 1.4 AU/s, P = 0.001) than that of sinus beats. The coupling interval of DAD‐like DDs was longer than that of the preceding normal beats (407 ± 48 ms vs 371 ± 44 ms, P = 0.002).</P><P> <B> <I>Conclusion:</I> </B> The isoproterenol‐induced LDCAE of superior SAN induced a full action potential in most cases. However, if the LDCAE was too small to trigger an action potential, then it induces only DAD‐like DD. The failure of DAD‐like DD to consistently trigger a sinus beat is a novel mechanism of atrial arrhythmogenesis. <I>(J Cardiovasc Electrophysiol, Vol. 22, pp. 448‐454)</I></P>

Perovskite Solar Cells with 12.8% Efficiency by Using Conjugated Quinolizino Acridine Based Hole Transporting Material

Qin, Peng,Paek, Sanghyun,Dar, M. Ibrahim,Pellet, Norman,Ko, Jaejung,Gra&#x308,tzel, Michael,Nazeeruddin, Mohammad Khaja American Chemical Society 2014 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.136 No.24

<P>A low band gap quinolizino acridine based molecule was designed and synthesized as new hole transporting material for organic–inorganic hybrid lead halide perovskite solar cells. The functionalized quinolizino acridine compound showed an effective hole mobility in the same range of the state-of-the-art spiro-MeOTAD and an appropriate oxidation potential of 5.23 eV vs the vacuum level. The device based on this new hole transporting material achieved high power conversion efficiency of 12.8% under the illumination of 98.8 mW cm<SUP>–2</SUP>, which was better than the well-known spiro-MeOTAD under the same conditions. Moreover, this molecule could work alone without any additives, thus making it to be a promising candidate for solid-state photovoltaic application.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2014/jacsat.2014.136.issue-24/ja503272q/production/images/medium/ja-2014-03272q_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja503272q'>ACS Electronic Supporting Info</A></P>

Fine-tuning the Electronic Structure of Organic Dyes for Dye-Sensitized Solar Cells

Gao, Peng,Tsao, Hoi Nok,Gra&#x308,tzel, Michael,Nazeeruddin, Mohammad K. American Chemical Society 2012 Organic letters Vol.14 No.17

<P>A series of metal-free organic dyes exploiting different combinations of (hetero)cyclic linkers (benzene, thiophene, and thiazole) and bridges (4<I>H</I>-cyclopenta[2,1-<I>b</I>:3,4-<I>b′</I>]dithiophene (CPDT) and benzodithiophene (BDT)) as the central π-spacers were synthesized and characterized. Among them, the sensitizer containing the thiophene and CPDT showed the most broad incident photon-to-current conversion efficiency spectra, resulting in a solar energy conversion efficiency (η) of 6.6%.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orlef7/2012/orlef7.2012.14.issue-17/ol301730c/production/images/medium/ol-2012-01730c_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ol301730c'>ACS Electronic Supporting Info</A></P>

Thermal Behavior of Methylammonium Lead-Trihalide Perovskite Photovoltaic Light Harvesters

Dualeh, Amalie,Gao, Peng,Seok, Sang Il,Nazeeruddin, Mohammad Khaja,Gra&#x308,tzel, Michael American Chemical Society 2014 Chemistry of materials Vol.26 No.21

<P>Recently organic–inorganic hybrid perovskites have attracted attention as light harvesting materials in mesoscopic cells. While a considerable number of deposition and formation methods have been reported for the perovskite crystalline material, most involve an annealing step. As such, the thermal behavior of this material and its individual components is of crucial interest. Here, we examine the thermal properties of the CH<SUB>3</SUB>NH<SUB>3</SUB>PbX<SUB>3</SUB> (X = I or Cl) perovskite using thermogravimetric analysis. The role of the precursors is exposed, and the effect of the formation of excess organic species is investigated. The sublimation behavior of the organic component is intensively scrutinized. Furthermore, differential scanning calorimetry is employed to probe the crystal phase structure, revealing subtle differences depending on the deposition method.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cmatex/2014/cmatex.2014.26.issue-21/cm502468k/production/images/medium/cm-2014-02468k_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cm502468k'>ACS Electronic Supporting Info</A></P>

Correlations between Ion Conductivity and Polymer Dynamics in Hyperbranched Poly(ethylene oxide) Electrolytes for Lithium-Ion Batteries

Lee, Sung-Il,Scho&#x308,mer, Martina,Peng, Huagen,Page, Kirt A.,Wilms, Daniel,Frey, Holger,Soles, Christopher L.,Yoon, Do Y. American Chemical Society 2011 Chemistry of materials Vol.23 No.11

<P>Poly(ethylene oxide)s with varying degrees of hyperbranching are effective at preventing the crystallization of PEO and lead to approximately a 100-fold increase in the Li-ion conductivity below 50 °C as compared with linear PEO. The Li-ion conductivities, which increase further upon permethylation of the hydroxyl termini, are found to correlate quantitatively with the fast segmental dynamics of PEO as measured by inelastic neutron scattering.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cmatex/2011/cmatex.2011.23.issue-11/cm103696g/production/images/medium/cm-2010-03696g_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cm103696g'>ACS Electronic Supporting Info</A></P>