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Conjugated polymers (CPs) as photocatalysts have evoked substantial interest. Their geometries and physical (e.g., chemical and thermal stability and solubility), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential, and exciton binding energy) can be easily tuned via structural design. In addition, they are of light weight (i.e., mainly composed of C, N, O, and S). To improve the photocatalytic performance of CPs and better understand the catalytic mechanisms, many strategies with respect to material design have been proposed. These include tuning the bandgap, enlarging the surface area, enabling more efficient separation of electron–hole pairs, and enhancing the charge carrier mobility. In particular, donor–acceptor (D–A) polymers were demonstrated as a promising platform to develop high-performance photocatalysts due to their easily tunable bandgaps, high charge carrier mobility, and efficient intramolecular charge transfer. In this minireview, recent advances of D–A polymers in photocatalytic hydrogen evolution are summarized with a particular focus on modulating the optical and electronic properties of CPs by varying the acceptor units. The challenges and prospects associated with D–A polymer-based photocatalysts are described as well.

Five carbazole and diketopyrrolopyrrole-based donor-acceptor (D-A) new π-conjugated oligomers (π-COs) with gradually elongated lengths are facilely synthesized via a single pot of direct C–H arylation with merits of atom- and step-economy. The structure-property-performance correlations of these π-COs and their parent polymer are studied in detail by opto-electronic characterizations and bulk heterojunction (BHJ) organic photovoltaic (OPV) devices. It is found that the π-COs having longer lengths enable better performance in OPVs owing to the enhanced intermolecular interaction with the elongation of the conjugations. The above results not only highlight the powerful synthetic strategy here provided, but also reveal that π-COs with unique properties might find promising application in OPVs.

Background: Temporal lobe epilepsy (TLE) is the most common intractable epilepsy in adults, and elucidation of the underlying pathological mechanisms is needed. Voltage-gated chloride channels (ClC) play diverse physiological roles in neurons. However, less is known regarding their functions in the epilepogenesis of TLE. Methods: ClC-mediated current and the spontaneous inhibitory synaptic currents (sIPSC) in hippocampal neurons of epileptic lesions were investigated by electrophysiological recording. The EEG data were analyzed by Z-scored wavelet and Fourier transformations. The expression of ClC-3, a member of ClC gene family, was detected by immunostaining and western blot. Findings: ClC-mediated current was increased in the hippocampal neurons of chronic TLE mice. Application of chloride channel blockers, NPPB (5-Nitro-2- [3-phenylpropylamino] benzoic acid) and DIDS (4,4’-Diisothiocyanato-2,2’-stilbenedisulfonic acid disodium salt) reduced ClC-mediated current and increased inhibitory synaptic transmission in TLE mice. NPPB and DIDS reduced the seizure frequency and the average absolute power of ictal high-frequency oscillations (HFOs, 80-500 Hz) in TLE mice. In addition, both drugs induced outwardly rectified currents, which might be tonic inhibitory currents in the hippocampal neurons of TLE patients. Furthermore, the expression of ClC-3 was increased in the hippocampus of TLE mice and patients and positively correlated with both the absolute power and number of ictal HFOs per seizure in the sclerotic hippocampus. Interpretation: These data suggest that ClC participate in the epilepogenetic process of TLE and the inhibition of ClC may have anti-epileptic effect. Funding: This work was supported by National Natural Science Foundation of China (No. 81601143, No. 81771217).

Objective: Central nervous system infections (CNSIs), especially viral encephalitis and meningitis, are well-recognized causes of medically refractory epilepsy. Although surgery is an effective and durable intervention against these infections, the seizure control outcomes described in previous surgical series have been variable. Accordingly, it is not clear which variables are most valuable in predicting seizure control following surgery for CNSI. The aim of this meta-analysis was to identify the predictors of favorable surgical outcomes in CNSI-related epilepsy.Methods: The PubMed, EMBASE, Cochrane Library, WANGFANG, VIP, CBM, and CNKI databases were searched for studies according to the inclusion criteria. Prognostic factors, surgical outcomes, and patient characteristics were extracted. Heterogeneity was detected by the I2 and Q statistics.Results: Seventeen studies were included in our meta-analysis. Eight predictors of favorable outcomes (Engel Class I/II) were determined, including abnormal MRI findings, meningitis, temporal location only, regional ictal pattern, unilateral ictal pattern, older age at epilepsy, longer silent period, and longer time from infection, as follows: OR = 3.34 (95% CI 1.44–7.74), OR = 0.31 (95% CI 0.13–0.70), OR = 0.34 (95% CI 0.16–0.74), OR = 5.65 (95% CI 1.75–18.30), and OR = 9.53 (95% CI 2.36–38.48), respectively, and MD = 2.15 (95% CI 0.20–4.11), MD = 2.40 (95% CI 0.09–4.70), and MD = 8.49 (95% CI 1.50–15.48), respectively. A subgroup analysis found the following associations: regional and unilateral ictal patterns in viral encephalitis, a younger age at infection in parasitic encephalopathy, an older age at surgery, a longer time from onset, and a longer time from infection in unexplained meningitis. A sensitivity analysis restricted to studies that included each variable yielded robust results. Little evidence of publication bias was observed.Conclusions: This meta-analysis suggests that abnormal MRI findings, meningitis, temporal location only, regional and unilateral ictal patterns, older age at epilepsy, longer silent period, and longer time from infection are predictive factors in patients with favorable surgical outcomes in CNSI-related epilepsy. In addition, different infective agents influenced the results in regional and unilateral ictal patterns in ictal electroencephalography, as well as the relationship between age at infection and surgery and the time from epilepsy onset and infection.

Diketopyrrolopyrrole (DPP) is an important type of π-conjugated building block for high-performance organic electronic materials. DPP-based conjugated materials are usually synthesized via Suzuki, Stille, or Negishi cross-coupling reactions, which require organometallic precursors. In this paper, a series of novel phenyl-cored DPP molecules, including five meta-phenyl-cored molecules and four para-phenyl-cored molecules, have been synthesized in moderate to good yields, in a facile manner, through the Pd-catalyzed direct arylation of C−H bonds, and their optoelectrical properties have been investigated in detail. All new molecules have been fully characterized by NMR, MALDI-TOF MS, elemental analysis, UV−visible spectroscopy, and cyclic voltammetry. This synthetic strategy has evident advantages of atom- and step-economy and low cost, compared with traditional cross-coupling reactions.

In the title compound, C15H13FN2O, the dihedral angle between the benzene rings is 16.9 (2)°. The F atom and the O atom are in a syn conformation. In the crystal, molecules are linked by N—H...O hydrogen bonds to generate C(4) chains propagating along the b-axis direction.

In the title compound, C15H13N3O3, the dihedral angle between the benzene rings is 1.01 (3)° and that between the nitro group and its attached ring is 5.99 (15)°. In the crystal, molecules are linked by N—H...O hydrogen bonds generating C(4) chains along [010].

Lennox-Gastaut syndrome (LGS) is a devastating and refractory generalized epilepsy affecting children and adolescents. In this study we report the results of resective surgery in 18 patients with LGS phenotype who underwent single-lobe/lesionectomy or multilobe resection plus multiple subpial transection and/or callosotomy. After surgery, seven patients became completely seizure-free (Engel Class I) and five almost seizure-free (Engel Class II). Additional four had significant seizure control (Engel Class III), and two had no change in seizure frequency (Engel Class IV). Of the 4 patients without any lesion on brain MRI, 2 ended with Engel Class II, 1 with III and the other with IV in Engels’ classification. Mean intelligence quotient (IQ) increased from 56.1 ± 8.1 (mean ± SD) before operation to 67.4 ± 8.2 (mean ± SD) after operation, a significant improvement (P=0.001). Results also indicated that the younger the patient at surgery, or the shorter the interval between onset of seizure and resective operation, the better the intellectual outcome. Our data suggest that resective epilepsy surgery can be successful in patients with LGS phenotype as long as the EEG shows dominance of discharges in one hemisphere and corresponding ipsilateral imaging findings, even with contralateral ictal discharges.

In the title molecule, C15H13BrN2O2, an intramolecular O—H...N hydrogen bond influences the molecular conformation; the two benzene rings form a dihedral angle of 13.6 (3)°. In the crystal, intermolecular N—H...O hydrogen bonds link the molecules into chains along the a axis and weak intermolecular C—H...O hydrogen bonds further link these chains into layers parallel to the ac plane.

In the molecule of the title compound, C17H13N3O2, the naphthyl ring system and the pyridine ring form a dihedral angle of 12.2 (3)°. An intramolecular O—H...N hydrogen bond generates a six-membered ring with an S(6) ring motif. This also contributes to the relative overall near planarity of the molecule [r.m.s. deviation of all 22 non-H atoms = 0.107 (5) Å]. In the crystal, molecules are linked through intermolecular N—H...N hydrogen bonds, forming chains along the a axis.

In the hydrazone molecule of the title compound, C15H12ClN3O4·H2O, the two benzene rings form a dihedral angle of 3.6 (1)°. In the crystal structure, the solvent water molecules are involved in the formation of intermolecular N—H...O and O—H...N hydrogen bonds, which link the molecules into double ribbons extending along the b axis. Intermolecular π–π interactions between the aromatic rings [centroid–centroid distances = 3.712 (3) and 3.672 (3) Å] link these ribbons further into layers parallel to the ab plane.

In the hydrazone molecule of the title compound, C13H9I2N3O2·CH3CN, the aromatic rings form a dihedral angle of 9.4 (3)°. In the crystal structure, intermolecular I...N interactions [3.099 (4) Å] link hydrogen-bonded aggregates of the hydrozone and solvent molecules related by translation along the b axis into chains. An intramolecular O—H...N hydrogen bond forms an S(6) ring.

In the title compound, C19H16N2O2, the benzene ring and naphthyl ring system are inclined at a dihedral angle of 16.1 (3)°. An intramolecular O—H...N hydrogen bond influences the molecular conformation. In the crystal, molecules are linked through N—H...O hydrogen bonds into chains running along the a axis.

In the title compound, C15H13BrN2O3, the two benzene rings form a dihedral angle of 16.9 (2)°. An intramolecular O—H...N hydrogen bond affects the molecular conformation. In the crystal structure, molecules are linked through N—H...O hydrogen bonds into chains running along the a axis.

In the title compound, C17H19N3O2, the two benzene rings form a dihedral angle of 89.2 (2)°. In the crystal structure, molecules are linked through N—H...O hydrogen bonds, forming C(4) chains running along the c axis.

In the title compound, C15H13BrN2O3, the molecule adopts an E configuration about the C=N bond and the two benzene rings form a dihedral angle of 20.3 (3)°. In the molecule, there are two intramolecular hydrogen bonds, viz. O—H...N and N—H...O, involving the hydroxy substituent, the methoxy O atom and the hydrazide NH group and N atom. In the crystal structure, molecules are linked through N—H...O hydrogen bonds, forming chains propagating along [010].

In the title compound, C15H13BrN2O4·CH4O, the two benzene rings form a dihedral angle of 3.2 (2)°. An intramolecular O—H...N hydrogen bond is observed. In the crystal structure, molecules are linked through O—H...O and N—H...O hydrogen bonds, forming a two-dimensional network parallel to (10overline{1}).

In the title compound, C14H11N3O4, the two benzene rings form a dihedral angle of 45.3 (3)°. The nitro group is twisted out of the attached ring by a dihedral angle of 37.5 (3)°. In the crystal structure, molecules are linked into a two-dimensional network parallel to (100) by O—H...O and N—H...O hydrogen bonds.

Background: Focal cortical dysplasia type IIb (FCD IIb) and tuberous sclerosis complex (TSC) are well-recognized causes of chronic intractable epilepsy in children. Accumulating evidence suggests that activation of the microglia/macrophage and concomitant inflammatory response in FCD IIb and TSC may contribute to the initiation and recurrence of seizures. The membrane glycoproteins CD47 and CD200, which are highly expressed in neurons and other cells, mediate inhibitory signals through their receptors, signal regulatory protein α (SIRP-α) and CD200R, respectively, in microglia/macrophages. We investigate the levels and expression pattern of CD47/SIRP-α and CD200/CD200R in surgically resected brain tissues from patients with FCD IIb and TSC, and the potential effect of soluble human CD47 Fc and CD200 Fc on the inhibition of several proinflammatory cytokines associated with FCD IIb and TSC in living epileptogenic brain slices in vitro. The level of interleukin-4 (IL-4), a modulator of CD200, was also investigated.Methods: Twelve FCD IIb (range 1.8-9.5 years), 13 TSC (range 1.5-10 years) patients, and 6 control cases (range 1.5-11 years) were enrolled. The levels of CD47/SIRP-α and CD200/CD200R were assessed by quantitative real-time polymerase chain reaction and western blot. The expression pattern of CD47/SIRP-α and CD200/CD200R was investigated by immunohistochemical analysis, and the cytokine concentrations were measured by enzyme-linked immune-sorbent assays.Results: Both the messenger RNA and protein levels of CD47, SIRP-α, and CD200, as well as the mRNA level of IL-4, were downregulated in epileptogenic lesions of FCD IIb and TSC compared with the control specimens, whereas CD200R levels were not significantly changed. CD47, SIRP-α, and CD200 were decreasingly expressed in dysmorphic neuron, balloon cells, and giant cells. CD47 Fc and CD200 Fc could inhibit IL-6 release but did not suppress IL-1β or IL-17 production.Conclusions: Our results suggest that microglial activation may be partially caused by CD47/SIRP-α- and CD200/CD200R-mediated reductions in the immune inhibitory pathways within FCD IIb and TSC cortical lesions where chronic neuroinflammation has been established. Upregulation or activation of CD47/SIRP-α and CD200/CD200R may have therapeutic potential for controlling neuroinflammation in human FCD IIb and TSC. [ABSTRACT FROM AUTHOR]

A novel 315-MHz OOK self-quenching super-regenerative wireless receiver is presented in this letter. A self-acceleration start-up mechanism is proposed, which employs a positive feedback to speed up the start-up time of super-regenerative oscillator for the “1” input signals. An adaptive reference generation is proposed to track the strength of input signal dynamically. The presented receiver can alleviate the design difficulties of the demodulation circuit and improve the rejection of interferences effectively. The prototype chip is fabricated with Central Semiconductor Manufacturing Corporation 0.5- \mu \textm mixed CMOS process. The chip area is 770\,\,\mu \textm\,\,\times680\,\,\mu \textm and the current consumption is 2.5 mA with 5-V supply voltage. The measurement results show that the sensitivity of the proposed receiver improves 11 dB for 2-kb/s OOK input signal when the self-acceleration start-up is activated. [ABSTRACT FROM PUBLISHER]

We demonstrate that the electroluminescent performances of organic light-emitting diodes are significantly improved by employing a zinc phthalocyanine (ZnPc)-based composite hole transport layer (c-HTL). The optimum ris-(8-hydroxyquinoline)aluminum (Alq3)-based organic light-emitting diode with a c-HTL exhibits a lower turn-on voltage of 2.8 V, a higher maximum current efficiency of 3.40 cd/A and a higher maximum power efficiency of 1.91 lm/W, which are superior to those of the conventional device (turn-on voltage of 3.8 V, maximum current efficiency of 2.60 cd/A, and maximum power efficiency of 1.21 lm/W). We systematically studied the effects of different kinds of N'-diphenyl-N,N'-bis(1-naphthyl)(1,1'-biphenyl)-4,4'diamine (NPB):ZnPc c-HTL. Meanwhile, we also investigate their mechanisms different from that in the case of using ZnPc as buffer layer. The specific analysis is based on the absorption spectra of the hole transporting material and current density—voltage characteristics of the corresponding hole-only devices. [ABSTRACT FROM AUTHOR]

In terms of the transmission theory of the arrayed waveguide grating (AWG), parameter optimization is performed, and bending effect of arrayed waveguides on transmission characteristics is analyzed for a 33x33 polymeric AWG multiplexer around the central wavelength of 1550.918 nm with the wavelength spacing of 0.8 nm. Analytical results show that the bending of arrayed waveguides causes the phaseshift of the light propagating in the AWG, results in the shift of the transmission spectrum, and brings about the variation of the crosstalk. For the designed AWG device, the shift of the transmission spectrum is about 0.01 nm, which is much less than the wavelength spacing of 0.8 nm. [ABSTRACT FROM AUTHOR]

This study demonstrates a novel athermal arrayed waveguide grating (AWG) which is composed of silica/polymer hybrid materials on a silicon substrate. The temperature -dependent wavelength shift of the AWG depends on the refractive indices of the materials and the size of the waveguide. The athermalization of the AWG can be realized by selecting the proper values of the material and structural parameters of the device. [ABSTRACT FROM AUTHOR]

An efficient technique is proposed to flatten the spectral response of an arrayed waveguide grating (AWG) multiplexer. By subtracting an increment from the length difference of odd arrayed waveguides and by adding the same increment to that of even arrayed waveguides, a boxlike spectral response can be obtained. The simulated result for a 17 × 17 polymer AWG shows that the boxlike spectral response has a 3-dB bandwidth of 0.49 nm, and the crosstalk is about or less than -28 dB for every output channel. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 916–919, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21518 [ABSTRACT FROM AUTHOR]

We report on a white hybrid light-emitting device employing a mixture of ternary CdSe/ZnS quantum dots (QDs) as an emitting layer (EML) and a small molecular material tris(8-hydroxyquinoline) aluminum (Alq3) as an electron-transporting layer. The film morphology of the spin-coated mixture of QDs is strongly improved via thermal annealing, and therefore a close-packed QD-EML is realized between organic charge-transporting layers. As a result, compared to the device with an unannealed QD-EML, the emission of Alq3 is deeply suppressed. In addition, a maximum luminance of more than 1000 cd/m2 and a maximum luminous efficiency of 2.2 cd/A are achieved. [ABSTRACT FROM AUTHOR]

A 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine thin film doped with Fe3O4 has been demonstrated an efficient p-type hole-injection layer (HIL) in organic light-emitting devices (OLEDs). The tris-(8-hydroxyquinoline) aluminum-based OLEDs with the p-type HIL exhibit a very low turn-on voltage of 2.4 V and a high luminance of 29 360 cd/m2 at 8 V, while it is 3 V and 6005 cd/m2, respectively, for the nondoped devices. The improvement in the device performance is clarified as arising from the improved hole injection and transport by the results of ultraviolet/visible/near-infrared absorption, x-ray photoelectron spectra and current density-voltage characteristics of hole-only devices. [ABSTRACT FROM AUTHOR]

Hole injection improvement in organic light-emitting devices with Fe3O4 as a buffer layer on indium tin oxide (ITO) has been demonstrated. The luminance and the current density are significantly enhanced by using the Fe3O4/ITO anode, as well as the turn-on voltage is reduced by 1.5 V compared to the devices without the buffer. Results of atom force microscopy, x ray, and UV photoelectron spectroscopy studies reveal that the enhanced hole injection is attributed to the modification of the ITO surface and the reduced hole-injection barrier by the insertion of the Fe3O4 thin film between the ITO and hole-transporting layer. [ABSTRACT FROM AUTHOR]