Fused Heptacyclic-Based Acceptor-Donor-Acceptor Small Molecules: N-Substitution toward High-Performance Solution-Processable Field-Effect Transistors

Zhang, Guobing,Zhao, Yao,Kang, Boseok,Park, Sangsik,Ruan, Jiufu,Lu, Hongbo,Qiu, Longzhen,Ding, Yunsheng,Cho, Kilwon American Chemical Society 2019 Chemistry of materials Vol.31 No.6

<P>Although various donor-acceptor (D-A) small molecules with high power conversion efficiency have been reported, D-A small molecules with high field-effect mobility are still rare. In this work, two new A-D-A small molecules with a rigid indacenodithieno[3,2-<I>b</I>]thiophene (<B>IDTT</B>) moiety as the central core and both ends capped with strong electron-withdrawing indole-2,3-dione (<B>IDD</B>) and N-substituted pyrrolo[2,3-<I>b</I>]pyridine-2,3-dione (<B>IDD-N</B>) were synthesized and characterized for applications in solution-processable organic field-effect transistors (OFETs). A N atom was introduced to the <B>IDD</B> units to enhance the planarity and structural ordering by noncovalent interactions, leading to a dramatic effect on the small molecule. The unsubstituted small molecule (<B>IDTT-IDD</B>) did not show any field-effect performance, whereas an encouraging hole mobility of 7.7 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP> with an average mobility of 6.1 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP> was obtained for solution-processable OFETs based on the N-substituted one (<B>IDTT-IDD-N</B>). This work provided a simple and effective molecular strategy for the design of D-A small molecules for high-performance solution-processable OFETs.</P> [FIG OMISSION]</BR>

Chirality detection of amino acid enantiomers by organic electrochemical transistor

Zhang, Lijun,Wang, Guiheng,Xiong, Can,Zheng, Lei,He, Jianbo,Ding, Yunsheng,Lu, Hongbo,Zhang, Guobing,Cho, Kilwon,Qiu, Longzhen Elsevier 2018 Biosensors & bioelectronics Vol.105 No.-

<P><B>Abstract</B></P> <P>Chiral recognition of α-amino acids is attracting increasing interest due to the importance of α-amino acids in protein metabolism as well as in food products and pharmaceuticals. Organic electrochemical transistors (OECTs) with gate electrodes modified with molecularly imprinted polymer (MIP) films were fabricated and successfully used as highly selective and sensitive chiral recognition biosensors for <SMALL>D/L</SMALL>-tryptophan (<SMALL>D</SMALL> <SMALL>/</SMALL> <SMALL>L</SMALL>-Trp) and <SMALL>D/L</SMALL>-tyrosine (<SMALL>D</SMALL> <SMALL>/</SMALL> <SMALL>L</SMALL>-Tyr). The MIP films, which can specifically recognize and has an electrocatalytic effect on the oxidation of Trp and Tyr, together with the amplification function of an OECT, provide a highly sensitive and selective OECT biosensor. The sensor showed a linear response range for <SMALL>L</SMALL>-Trp and <SMALL>L</SMALL>-Tyr from 300 nM to 10 μM with a sensitivity of 3.19 and 3.64 μA/μM, respectivity. And the detection limit for <SMALL>L</SMALL>-Trp and <SMALL>L</SMALL>-Tyr is of 2 nM and 30 nM (S/N > 3). The selectivity factors of <SMALL>L</SMALL>-Trp, <SMALL>D</SMALL>-Trp, <SMALL>L</SMALL>-Tyr and <SMALL>D</SMALL>-Tyr to their enantiomers are 11.6, 3.5, 14.5 and 2.6, respectively. This method can pave the way for widespread applications of OECT-based sensors in chiral material identification.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An novel chiral recognition MIP-OECT sensor was developed. </LI> <LI> The MIP films showed good performance of selective and electro-catalytic oxidation for Trp and Tyr. </LI> <LI> The MIP films together with the amplification function of an OECT afforded a highly sensitive, selective sensor for chirality detection of amino acid enantiomers. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A bis(2-oxoindolin-3-ylidene)-benzodifuran-dione containing copolymer for high-mobility ambipolar transistors

Zhang, Guobing,Li, Peng,Tang, Longxiang,Ma, Jingxuan,Wang, Xianghua,Lu, Hongbo,Kang, Boseok,Cho, Kilwon,Qiu, Longzhen The Royal Society of Chemistry 2014 Chemical communications Vol.50 No.24

<P>A bis(2-oxoindolin-3-ylidene)-benzodifuran-dione (BIBDF)-based low band gap polymer (PBIBDF-BT), containing a solubilizing alkyl chain bithiophene unit as a donor, has been synthesized. The polymer with a low-lying LUMO/HOMO energy level (−4.03/−5.55 eV) exhibits efficient ambipolar charge transport. The electron and hole mobilities are as high as 1.08 and 0.30 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>, respectively.</P> <P>Graphic Abstract</P><P>The PBIBDF-BT polymer exhibits high ambipolar charge transport with electron and hole mobilities as high as 1.08 and 0.30 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>, respectively. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc48695h'> </P>

Synthesis and characterization of thieno-isoindigo derivative-based near-infrared conjugated polymer for ambipolar field-effect transistors and photothermal conversion

Zhang, Guobing,Dai, Yanrong,Wang, Dong,Liu, Yu,Lu, Hongbo,Qiu, Longzhen,Cho, Kilwon Elsevier 2017 Dyes and pigments Vol.147 No.-

<P><B>Abstract</B></P> <P>A new thieno-isoindigo derivative, (3<I>E</I>,7<I>E</I>)-3,7-bis(4-(2-decyltetradecyl)-4<I>H</I>-thieno[3,2-<I>b</I>]pyrrole-5,6-dione)-5,7-dihydropyrrolo[2,3-<I>f</I>]indole-2,6(1<I>H</I>,3<I>H</I>)-dione (<B>BTPDI</B>), was designed and synthesized. A donor−acceptor conjugated polymer (<B>PBTPDI-TT</B>) was also synthesized with this new unit as the acceptor and thieno[3,2-<I>b</I>]thiophene as the donor. The microstructure, photophysical, electrochemical, field-effect properties and photothermal performances were investigated. The polymer showed a broad absorption spectrum that spanned across the near-infrared (NIR) region (780–1300 nm), with a very low bandgap (∼0.95 eV), deep lowest unoccupied molecular orbital, and suitable highest occupied molecular orbital levels. As a result, the polymer-based organic field-effect transistors showed highly balanced hole and electron transport characteristics with a hole mobility of 0.027 cm<SUP>2</SUP> V<SUP>−1</SUP>s<SUP>−1</SUP> and an electron mobility of 0.022 cm<SUP>2</SUP> V<SUP>−1</SUP>s<SUP>−1</SUP>. The polymer nanoparticles showed good reusability under NIR (980 nm) irradiation and could also effectively convert NIR light to heat at an excellent efficiency of 20.3%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new thieno-isoindigo derivative dye and its polymer were designed and synthesized. </LI> <LI> The polymer showed ultra broad absorption spectra that spanned across the near-infrared region and remarkably low bandgap. </LI> <LI> The new polymer showed highly balanced hole and electron transport characteristics. </LI> <LI> Polymer nanoparticles showed excellent photothermal conversion efficiency under 980 nm irradiation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

ROCK1 induces dopaminergic nerve cell apoptosis via the activation of Drp1-mediated aberrant mitochondrial fission in Parkinson’s disease

Qian Zhang,Changpeng Hu,Jingbin Huang,Wuyi Liu,Wenjing Lai,Faning Leng,Qin Tang,Yali Liu,Qing Wang,Min Zhou,Fangfang Sheng,Guobing Li,Rong Zhang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Dopamine deficiency is mainly caused by apoptosis of dopaminergic nerve cells in the substantia nigra of themidbrain and the striatum and is an important pathologic basis of Parkinson’s disease (PD). Recent research has shownthat dynamin-related protein 1 (Drp1)-mediated aberrant mitochondrial fission plays a crucial role in dopaminergicnerve cell apoptosis. However, the upstream regulatory mechanism remains unclear. Our study showed that Drp1knockdown inhibited aberrant mitochondrial fission and apoptosis. Importantly, we found that ROCK1 was activated inan MPP+-induced PD cell model and that ROCK1 knockdown and the specific ROCK1 activation inhibitor Y-27632blocked Drp1-mediated aberrant mitochondrial fission and apoptosis of dopaminergic nerve cells by suppressing Drp1dephosphorylation/activation. Our in vivo study confirmed that Y-27632 significantly improved symptoms in a PDmouse model by inhibiting Drp1-mediated aberrant mitochondrial fission and apoptosis. Collectively, our findingssuggest an important molecular mechanism of PD pathogenesis involving ROCK1-regulated dopaminergic nerve cellapoptosis via the activation of Drp1-induced aberrant mitochondrial fission.

Interference Management by Vertical Beam Control Combined with Coordinated Pilot Assignment and Power Allocation in 3D Massive MIMO Systems

( Guomei Zhang ),( Bing Wang ),( Guobing Li ),( Fei Xiang ),( Gangming Lv ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.8

In order to accommodate huge number of antennas in a limited antenna size, a large scale antenna array is expected to have a three dimensional (3D) array structure. By using the Active Antenna Systems (AAS), the weights of the antenna elements arranged vertically could be configured adaptively. Then, a degree of freedom (DOF) in the vertical plane is provided for system design. So the three-dimension MIMO (3D MIMO) could be realized to solve the actual implementation problem of the massive MIMO. However, in 3D massive MIMO systems, the pilot contamination problem studied in 2D massive MIMO systems and the inter-cell interference as well as inter-vertical sector interference in 3D MIMO systems with vertical sectorization exist simultaneously, when the number of antenna is not large enough. This paper investigates the interference management towards the above challenges in 3D massive MIMO systems. Here, vertical sectorization based on vertical beamforming is included in the concerned systems. Firstly, a cooperative joint vertical beams adjustment and pilot assignment scheme is developed to improve the channel estimation precision of the uplink with pilots being reused across the vertical sectors. Secondly, a downlink interference coordination scheme by jointly controlling weight vectors and power of vertical beams is proposed, where the estimated channel state information is used in the optimization modelling, and the performance loss induced by pilot contamination could be compensated in some degree. Simulation results show that the proposed joint optimization algorithm with controllable vertical beams` weight vectors outperforms the method combining downtilts adjustment and power allocation.

Portal pressure gradient and serum albumin: A simple combined parameter associated with the appearance of ascites in decompensated cirrhosis treated with transjugular intrahepatic portosystemic shunt

Dongmei Zhao,Guobing Zhang,Mingquan Wang,Chaoxue Zhang,Jiabin Li 대한간학회 2019 Clinical and Molecular Hepatology(대한간학회지) Vol.25 No.2

Background/Aims: In recent years, greater assessment accuracy after transjugular intrahepatic portosystemic shunt (TIPS) to ascertain prognosis has become important in decompensated cirrhosis due to portal hypertension. The aim of this study was to assess the ratio of the portal pressure gradient (PPG) pre-TIPS (pre-PPG) to albumin (PPA), which influence ascites formation in cirrhotic patients in the 6-months after TIPS placement, and is a metric introduced in our study. Methods: This was a retrospective cohort study of 58 patients with decompensated cirrhosis admitted to an academic hospital for the purpose of TIPS placement. We collected the following data: demographics, laboratory measures, and PPG during the TIPS procedure. Then we analyzed the association between the above data and ascites formation post- TIPS in cirrhosis patients. Results: Twenty-two patients with ascites and 28 without ascites were evaluated. Univariate and binary logistic regression analysis were adjusted for the following variables: to determine prognosis; Child-Pugh scores, lymphocyte count, platelet count, hemoglobin level, albumin level and pre-PPG or PPA. The outcome showed that PPA was better than pre-PPG and albumin for predicting ascites according to area under receiver operating characteristic curves and a statistical model that also showed PPA’s influence 6-months post-TIPS. Conclusions: The combined measurement of pre-PPG and albumin, defined as PPA, may provide a better way to predict post-TIPS ascites in decompensated cirrhosis, which underlines the need for a large clinical trial in the future.

A New Dynamic Transmission-Mode Selection Scheme for AMC/HARQ-Based Wireless Networks

( Xiaohui Ma ),( Guobing Li ),( Guomei Zhang ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.11

In this paper, we study the cross-layer design for the AMC/HARQ-based wireless networks, and propose a new dynamic transmission-mode selection scheme to improve system spectrum efficiency. In the proposed scheme, dynamic thresholds for transmission-mode selection in each packet transmission and retransmission are jointly designed under the constraint of the overall packet error rate. Comparing with the existing schemes, the proposed scheme is inclined to apply higher modulation order at the first several (re)transmissions, which corresponds to higher-rate transmission modes thus higher average system spectrum efficiency. We also extend the cross-layer design to MIMO (Multi-input Multi-output) communication scenarios. Numerical results show that the proposed new dynamic transmission-mode selection scheme generally achieves higher average spectrum efficiency than the conventional and existing cross-layer design.

Tuning the Energy Levels of Aza-Heterocycle-Based Polymers for Long-Term <i>n</i>-Channel Bottom-Gate/Top-Contact Polymer Transistors

Ma, Suxiang,Zhang, Guobing,Wang, Feifei,Dai, Yanrong,Lu, Hongbo,Qiu, Longzhen,Ding, Yunsheng,Cho, Kilwon American Chemical Society 2018 Macromolecules Vol.51 No.15

<P>Conjugated polymer-based organic thin film transistors (OTFTs) have received tremendous attention due to their potential applications. In addition to their high performances, air stability is also essential for application and another main property that OTFTs have. In this paper, three aza-heterocycle (BABDF)-based polymers were designed and synthesized using strong donor thiophene-vinylene-thiophene (TVT), weak donor thiophene-cyanovinylene-thiophene (TCNT), and weak acceptor dithiazole (TZ) as co-units. The lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) energy levels were effectively lowered by introducing TCNT and TZ units, especially for PBABDF-TZ, for which the too much deep LUMO/HOMO energy levels of −4.28/-6.06 eV were obtained. These levels are low enough for air-stable electron transport and large enough for the hole injection barriers in OTFTs. Consequently, the unencapsulated bottom-gate/top-contact (BG/TC) devices exhibited unipolar electron transport under air conditions. Furthermore, these devices had high air stability and maintained unipolar electron transport with a mobility of up to 0.01 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP> during the one-year characterization period. Very low LUMO and HOMO levels were necessary for electron transport and the hole barriers, respectively, and both were important for long-term, air-stable <I>n</I>-channel polymer transistors.</P> [FIG OMISSION]</BR>

Multiple-Phase Energy Detection and Effective Capacity Based Resource Allocation Against Primary User Emulation Attacks in Cognitive Radio Networks

( Zongyi Liu ),( Guomei Zhang ),( Wei Meng ),( Xiaohui Ma ),( Guobing Li ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.3

Cognitive radio (CR) is regarded as an effective approach to avoid the inefficient use of spectrum. However, CRNs have more special security problems compared with the traditional wireless communication systems due to its open and dynamic characteristics. Primary user emulation attack (PUEA) is a common method which can hinder secondary users (SUs) from accessing the spectrum by transmitting signals who has the similar characteristics of the primary users’ (PUs) signals, and then the SUs’ quality of service (QoS) cannot be guaranteed. To handle this issue, we first design a multiple-phase energy detection scheme based on the cooperation of multiple SUs to detect the PUEA more precisely. Second, a joint SUs scheduling and power allocation scheme is proposed to maximize the weighted effective capacity of multiple SUs with a constraint of the average interference to the PU. The simulation results show that the proposed method can effectively improve the effective capacity of the secondary users compared with the traditional overlay scheme which cannot be aware of the existence of PUEA. Also the good delay QoS guarantee for the secondary users is provided.