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RNA transcribed from enhancers, i.e., eRNA, has been suggested to directly activate transcription by recruiting transcription factors and co-activators. Although there have been specific examples of eRNA functioning in this way, it is not clear how general this may be. We find that the AT-hook of SWI/SNF preferentially binds RNA and, as part of the esBAF complex, associates with eRNA transcribed from intronic and intergenic regions. Our data suggest that SWI/SNF is globally recruited in cis by eRNA to cell-type-specific enhancers, representative of two distinct stages that mimic early mammalian development, and not at enhancers that are shared between the two stages. In this manner, SWI/SNF facilitates recruitment and/or activation of MLL3/4, p300/CBP, and Mediator to stage-specific enhancers and super-enhancers that regulate the transcription of metabolic and cell lineage priming-related genes. These findings highlight a connection between ATP-dependent chromatin remodeling and eRNA in cell identity and typical- and super-enhancer activation.
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Linhagem da Célula , DNA Helicases , Elementos Facilitadores Genéticos , Proteínas Nucleares , Fatores de Transcrição , Animais , Humanos , Linhagem da Célula/genética , Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , DNA Helicases/metabolismo , DNA Helicases/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Background: Platinum-based combination chemotherapy, including cisplatin and carboplatin, are important cytotoxic anti-cancer agents that are widely used to treat various solid tumors. Carboplatin has a similar effect on survival in small cell lung cancer, but generally has a milder toxicity profile when compared with cisplatin. Both may cause moderate or severe neurotoxicity, but ocular neurotoxicity from carboplatin is rarely reported. Case presentation: A 79-year-old man underwent intravenous polychemotherapy (atezolizumab, etoposide, and carboplatin) for small cell lung cancer. One week after the second cycle of chemotherapy, he reported bilateral visual loss as hand motion in both eyes. Dilated fundus examination showed retinal arterial narrowing without hemorrhage, and diffuse choroidal and retinal thinning was observed in an optical coherence tomography scan. Fluorescein angiography revealed significantly delayed circulation without evidence of obstructive lesions. 30-Flicker electroretinogram testing showed a complete absence of cone response in both eyes. The patient's visual acuity aggravated to no light perception in both eyes, even after the cessation of chemotherapy. Conclusions: Carboplatin combination chemotherapy administered at therapeutic doses can result in irreversible visual loss, a side effect that is not widely acknowledged. When using carboplatin, physicians should be aware of its potential ocular toxicity.
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Carboplatina , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carboplatina/uso terapêutico , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Masculino , Idoso , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transtornos da Visão/induzido quimicamente , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagemRESUMO
A wireless solar water splitting device provides a means to achieve an inexpensive and highly distributed solar-to-fuel system owing to its portability, flexible scale, and simple design. Here, a highly efficient hydrogen-generating artificial leaf is introduced, which is a wireless configuration for converting solar energy into chemical energy, by integrating a hybrid perovskite (PSK) as the light absorber with catalysts for electrochemical reaction. First, a single integrated photoelectrochemical photocathode, and a spatially decoupled hydrogen evolution reaction catalyst, are fabricated. A decoupled geometry is adopted to enable the physical protection of the PSK layer from the electrolyte, thus allowing excellent stability for over 85 h. Additionally, an efficient dual photovoltaic module photocathode is fabricated to produce sufficient photovoltage to drive water splitting reactions, as well as a high photocurrent to achieve the applied-bias photoconversion efficiency (13.5%). To investigate the overall water splitting performance, a NiFe-OH catalyst is employed, and the device with a wired configuration achieves a photocurrent density of 9.35 mA cm-2 , corresponding to a solar to hydrogen (STH) efficiency of 11.5%. The device with a fully integrated wireless artificial leaf configuration exhibited a similar STH efficiency of over 11%, demonstrating the effectiveness of this cell design.
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Cleaning a fouled membrane using warm water, instead of commonly used fouling control chemicals, is an approach advocated in resource-limited settings, where small-scale membrane filtration is used to provide clean water. Thermoresponsive polymers coated onto membranes undergo a conformational change across their lower critical solution temperature (LCST), enabling foulant removal during such temperature-swing cleaning. However, their intrinsic hydrophobicity above the LCST poses a fundamental material challenge. In this study, we examine how thermoresponsive polymers can be optimally copolymerized with hydrophilic polymers by precisely manipulating monomer arrangement of thermoresponsive N-isopropylacrylamide and hydrophilic 2-[2-(2-methoxyethoxy)ethoxy]ethyl acrylate. We successfully grafted these copolymers with different monomer arrangements onto poly(ether sulfone) ultrafiltration membranes while maintaining other polymer characteristics, such as the degree of polymerization and grafting density, constant. We found that placing hydrophilic polymer blocks at the outermost surface above the thermoresponsive polymer blocks is critical to achieving high surface hydrophilicity while preserving the thermoresponsive functionality. We demonstrate enhanced fouling resistance and efficient temperature-swing cleaning with optimized copolymer design based on their interaction with bovine serum albumin during static adsorption, filtration, and cleaning processes. These findings emphasize the importance of accurately tailoring the polymer architecture to enable more efficient filtration with reduced fouling and the capability to effectively clean the fouled membrane by simply using warm water.
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Incrustação Biológica , Polímeros , Polímeros/química , Incrustação Biológica/prevenção & controle , Interações Hidrofóbicas e Hidrofílicas , Temperatura , Água/química , Membranas ArtificiaisRESUMO
PURPOSE: To evaluate the long-term prognosis of polypoidal choroidal vasculopathy (PCV) treated with anti-vascular endothelial growth factor (anti-VEGF) combined with verteporfin photodynamic therapy (PDT), according to polypoidal lesion regression. METHODS: This study retrospectively reviewed the data of 33 naïve eyes with PCV treated with anti-VEGF combined with verteporfin PDT and followed-up for at least 7 years. The collected data included demographic profile, best-corrected visual acuity (BCVA), central foveal thickness (CFT), PED volume, and presence of submacular hemorrhage. Regression of polypoidal lesion was determined using indocyanine green angiography and optical coherence tomography. All eyes were divided into regression or persistent groups, based on the polypoidal lesion regression one year after the initial combined treatment. RESULTS: BCVA improvement was maintained for 3 years in the regression (p = 0.001) and 1 year in the persistent (p = 0.006) groups, respectively. The mean BCVA of the regression group was better than that of the persistent group over 7 years, but the difference was significant only at 1 year (p = 0.037). The number of eyes which maintained BCVA less than or equal to 0.3 logMAR at 7 years was 11 eyes (64.7%) in regression group and 4 eyes (25.0%) in persistent group (p = 0.022). CONCLUSIONS: Regression of the polypoidal lesion at 1 year after the initial combination treatment was associated with favorable long-term visual prognosis, particularly in terms of maintaining good visual acuity.
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Doenças da Coroide , Fotoquimioterapia , Humanos , Verteporfina/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Fatores de Crescimento Endotelial/uso terapêutico , Fotoquimioterapia/métodos , Fator A de Crescimento do Endotélio Vascular , Vasculopatia Polipoidal da Coroide , Estudos Retrospectivos , Doenças da Coroide/diagnóstico , Doenças da Coroide/tratamento farmacológico , Angiofluoresceinografia , Injeções Intravítreas , Tomografia de Coerência ÓpticaRESUMO
Mechanically compliant conductors are of utmost importance for the emerging fields of soft electronics and robotics. However, the development of intrinsically deformable organic conductors remains a challenge due to the trade-off between mechanical performance and charge mobility. In this study, we report a solution to this issue based on size-selective ionic crosslinking. This rationally designed crosslinking mediated by length-regulated oligo(ethylene glycol) pendant groups and metal ions simultaneously improved the softness and toughness and ensured excellent mixed ionic-electronic conductivity in poly(3,4-ethylenedioxythiophene):polystyrene sulfonate composite materials. Moreover, the added ions remarkably promoted accumulation of charge carriers in response to temperature gradient, thus offering a viable approach to stretchable thermoelectric generators with enhanced stability against humidity.
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Chiral perovskites have emerged as promising candidates for polarization-sensing materials. Despite their excellent chiroptical properties, the nature of their multiple-quantum-well structures is a critical hurdle for polarization-based and spintronic applications. Furthermore, as the origin of chiroptical activity in chiral perovskites is still illusive, the strategy for simultaneously enhancing the chiroptical activity and charge transport has not yet been reported. Here, we demonstrated that incorporating a Lewis base into the lattice can effectively tune the chiroptical response and electrical properties of chiral perovskites. Through solid-state nuclear magnetic resonance spectroscopic measurements and theoretical calculations, it was demonstrated that the material property manipulation resulted from the change in the time-averaged structure induced by the Lewis base. Finally, as a preliminary proof of concept, a vertical-type circularly polarized light photodetector based on chiral perovskites was developed, exhibiting an outstanding performance with a distinguishability of 0.27 and a responsivity of 0.43 A W-1.
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Quasi 2D perovskite solar cells (PSCs) are promising light absorbers that overcome the inherent instabilities of 3D perovskites. High-performance and stable 2D PSCs require careful control over the crystallographic orientation and phase distribution. This study introduces a simple and universal bifacial stamping method to obtain highly oriented perovskite crystals with a reverse-graded structure, where the low-n-value 2D perovskite phases are located mainly at the film surfaces. Bifacial stamping of 3D perovskite films atop the 2D films enables incorporation of 2D spacer cations into the 3D film surfaces, forming reverse-graded quasi-2D perovskite films. During stamping, suppressed evaporation of the precursor solvent induces heterogeneous nucleation from the contact interface between the 2D and 3D films, resulting in well-crystallized perovskite films having out-of-plane alignments with respect to the substrate. Thus, a highly oriented and reverse-graded quasi-2D perovskite with an average n value of 18 is obtained with power conversion efficiency exceeding 17% and high open-circuit voltage of 1.11 V for iso-butylammonium (iso-BA)-based (iso-BA2 MAn -1 Pbn I3 n +1 ) PSCs. The unencapsulated device retains 92% of its initial efficiency after aging at 40 ± 5% relative humidity for 1200 h. This work provides a new strategy for fabricating highly oriented and phase-controlled quasi-2D PSCs.
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Neuroretinitis is a rare clinical entity, characterized by optic nerve edema and star-shape hard exudate around fovea. The clinical features include acute unilateral visual loss, dyschromatopsia, relative afferent pupillary defect and visual field abnormalities. Increased vascular permeability of the optic disc is the main pathophysiology. As it is a not fully known clinical entity, diagnosis is challenging. In this case, we use multimodal imaging to reveal pathophysiology and anatomical change of early mild neuroretinitis. Case presentation: A 28-year-old healthy woman presented to the clinic with mild blurred vision in her left eye. After complete ophthalmic examination, outer retinal thickening of the temporal peripapillary area and optic disc edema were observed. Two days after diagnosis, the retinal edema and visual symptoms were aggravated. A hard exudate, maybe a part of macular star, was observed. Multimodal imaging including optical coherence tomography (OCT), swept-source OCT angiography (SS-OCTA), fluorescein angiography, and indocyanine green angiography visualized choroidal thinning and insufficient circulation beneath the outer retinal edema. Following steroid pulse therapy, the retinal edema and blurred vision were completely resolved. Conclusions: Multimodal imaging suggested that unilateral optic disc edema and early macular star help the diagnosis of neuroretinitis. In SS-OCTA, we found focal choroidal insufficiency. The focal insufficient choroidal circulation might be a contribution factor for idiopathic neuroretinitis. Multimodal imaging including SS-OCTA may be a valuable tool for detecting and monitoring disease progression.
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Disco Óptico , Retinite , Adulto , Feminino , Angiofluoresceinografia , Humanos , Imagem Multimodal , Retinite/diagnóstico por imagem , Tomografia de Coerência ÓpticaRESUMO
Human action recognition is an important research area in the field of computer vision that can be applied in surveillance, assisted living, and robotic systems interacting with people. Although various approaches have been widely used, recent studies have mainly focused on deep-learning networks using Kinect camera that can easily generate data on skeleton joints using depth data, and have achieved satisfactory performances. However, their models are deep and complex to achieve a higher recognition score; therefore, they cannot be applied to a mobile robot platform using a Kinect camera. To overcome these limitations, we suggest a method to classify human actions in real-time using a single RGB camera, which can be applied to the mobile robot platform as well. We integrated two open-source libraries, i.e., OpenPose and 3D-baseline, to extract skeleton joints on RGB images, and classified the actions using convolutional neural networks. Finally, we set up the mobile robot platform including an NVIDIA JETSON XAVIER embedded board and tracking algorithm to monitor a person continuously. We achieved an accuracy of 70% on the NTU-RGBD training dataset, and the whole process was performed on an average of 15 frames per second (FPS) on an embedded board system.
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Atividades Humanas , Redes Neurais de Computação , Robótica , Algoritmos , Humanos , Articulações/fisiologia , Movimento , Fotografação/instrumentação , Esqueleto/fisiologiaRESUMO
Sample preparation steps (e.g., preconcentration and separation) are key to enhancing sensitivity and reliability in biomedical and analytical chemistry. However, conventional methods (e.g., ultracentrifugation) cause significant loss of sample as well as their contamination. In this study, we developed a paper-based three-dimensional (3D) origami ion concentration polarization preconcentrator (POP) for highly efficient and facile sample preparation. The unique design of POP enables simultaneous preconcentration and spatial separation of target analytes rapidly and economically. The POP comprises accordion-like multifolded layers with convergent wicking areas that can separate analytes based on their sizes in different layers, which can then be easily isolated by unfolding the POP. We first demonstrated 100-fold preconcentration of albumin and its isolation on the specific layers. Then, we demonstrated the simultaneous preconcentration and spatial separation of microspheres of three different sizes (with diameters of 0.02, 0.2, and 2 µm) on the different layers.
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EVs/exosomes are considered as the next generation of biomarkers, including for liquid biopsies. Consequently, the quantification of EVs/exosomes is crucial for facilitating EV/exosome research and applications. Paper-based enzyme-linked immunosorbent assay (p-ELISA) is a portable diagnostic system with low cost that is simple and easy to use; however, it shows low sensitivity and linearity. In this study, we develop p-ELISA for targeting EVs/exosomes by using streptavidin agarose resin-based immobilization (SARBI). This method reduces assay preparation times, provides strong binding, and retains good sensitivity and linearity. The time required for the total assay, including preparation steps and surface immobilization, was shortened to â¼2 h. We evaluated SARBI p-ELISA systems with/without CD63 capture Ab and then with fetal bovine serum (FBS) and EVs/exosome-depleted fetal bovine serum (dFBS). The results provide evidence supporting the selective capture ability of SARBI p-ELISA. We obtain semiquantitative p-ELISA results using an exosome standard (ES) and human serum (HS), with R2 values of 0.95 and 0.92, respectively.
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Exossomos , Papel , Sefarose/química , Estreptavidina/química , Anticorpos Imobilizados/imunologia , Biomarcadores/análise , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Soro/química , Tetraspanina 29/imunologia , Tetraspanina 30/imunologiaRESUMO
In this paper, we propose an averaging pixel current adjustment technique for reducing fixed pattern noise (FPN) in the bolometer-type uncooled infrared image sensor. The averaging pixel current adjustment technique is composed of active pixel, reference pixel, and calibration circuit. Polysilicon resistors were used in each active pixel and reference pixel. Resistance deviation among active pixels integrated with the same resistance value cause FPN. The principle of the averaging pixel current adjustment technique for removing FPN is based on the subtraction of dark current of the active pixel from the dark current of the reference pixel. The subtracted current is converted into the voltage, which contains pixel calibration information. The calibration circuit is used to adjust the calibration current. After calibration, the nano-ampere current is output with small deviation. The proposed averaging pixel current adjustment technique is implemented by a chip composed of a pixel array, a calibration circuit, average current generators, and readout circuits. The chip was fabricated using a standard 0.35 µm CMOS process and its performance was evaluated.
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This paper presents the effects of offset pixel aperture width on the performance of monochrome (MONO) CMOS image sensors (CISs) for a three-dimensional image sensor. Using a technique to integrate the offset pixel aperture (OPA) inside each pixel, the depth information can be acquired using a disparity from OPA patterns. The OPA is classified into two pattern types: Left-offset pixel aperture (LOPA) and right-offset pixel aperture (ROPA). These OPAs are divided into odd and even rows and integrated in a pixel array. To analyze the correlation between the OPA width and the sensor characteristics, experiments were conducted by configuring the test elements group (TEG) regions. The OPA width of the TEG region for the measurement varied in the range of 0.3-0.5 µm. As the aperture width decreased, the disparity of the image increased, while the sensitivity decreased. It is possible to acquire depth information by the disparity obtained from the proposed MONO CIS using the OPA technique without an external light source. Therefore, the proposed MONO CIS with OPA could easily be applied to miniaturized devices. The proposed MONO CIS was designed and manufactured using the 0.11 µm CIS process.
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Nutlin-3a is a non-genotoxic, p53-activating, MDM2 inhibitor being investigated as an anticancer agent. Although Nutlin-3a selectively antagonizes the ubiquitin E3 ligase activity of MDM2, its efficacy is not entirely regulated by MDM2 levels in cancer cells. Here, we report that the cytotoxic effects of Nutlin-3a are regulated by TRIAD1 via a positive feedback loop with p53. We found that Nutlin-3a enhanced TRIAD1 transcription in a p53-dependent manner. Using in silico analysis and promoter luciferase assays, we demonstrated that p53-mediated transcription of TRIAD1 is mediated by a p53 consensus sequence in the TRIAD1 promoter region. Silencing TRIAD1 expression in wild-type p53 (p53WT ) cancer cells suppressed Nutlin-3a-mediated p53 activation and p53 target gene expression. These effects were enhanced in TRIAD1-overexpressing p53WT cancer cells, but not in p53-deficient cancer cells. Furthermore, TRIAD1 knockdown significantly reduced the growth inhibitory and cytotoxic effects of Nutlin-3a in p53WT cancer cells, as demonstrated by cell viability assays, cell cycle analysis, clonogenic growth, and soft-agar colony forming assays. Together, these data indicate that TRIAD1 regulates Nutlin-3a-mediated p53 activation and the cytotoxic activity of Nutlin-3a. J. Cell. Biochem. 118: 1733-1740, 2017. © 2016 Wiley Periodicals, Inc.
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Imidazóis/farmacologia , Piperazinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Western Blotting , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Linhagem Celular Tumoral , Humanos , Interferência de RNA , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismoRESUMO
In addition to having proper energy levels and high hole mobility (µh) without the use of dopants, hole-transporting materials (HTMs) used in n-i-p-type perovskite solar cells (PSCs) should be processed using green solvents to enable environmentally friendly device fabrication. Although many HTMs have been assessed, due to the limited solubility of HTMs in green solvents, no green-solvent-processable HTM has been reported to date. Here, we report on a green-solvent-processable HTM, an asymmetric D-A polymer (asy-PBTBDT) that exhibits superior solubility even in the green solvent, 2-methylanisole, which is a known food additive. The new HTM is well matched with perovskites in terms of energy levels and attains a high µh (1.13 × 10-3 cm2/(V s)) even without the use of dopants. Using the HTM, we produced robust PSCs with 18.3% efficiency (91% retention after 30 days without encapsulation under 50%-75% relative humidity) without dopants; with dopants (bis(trifluoromethanesulfonyl) imide and tert-butylpyridine, a 20.0% efficiency was achieved. Therefore, it is a first report for a green-solvent-processable hole-transporting polymer, exhibiting the highest efficiencies reported so far for n-i-p devices with and without the dopants.
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Two Gram-stain-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacteria, designated strains T2T and T5, were isolated from a culture of Microcystis from Daejeon, Republic of Korea. Comparative 16S rRNA gene sequence studies placed the new isolates in the class Alphaproteobacteria and, notably, most closely related to Blastomonasaquatica PE 4-5T, Blastomonas natatoria DSM 3183T and Blastomonas ursincola KR-99T showing 99.4â%, 98.2â% and 97.9â% 16S rRNA gene sequence similarities, respectively. The two novel strains shared 100â% similarity with each other. The cells of strains T2T and T5 formed yellow colonies on R2A agar and contained Q-10 as the only ubiquinone, sphingoglycolipid, phosphatidylethanolamine, phosphatidylcholine, and phosphatidylglycerol as major polar lipids, and C17â:â1ω6c, summed feature 8 (C18â:â1ω7c and/or C18â:â1ω6c), C17â:â1ω8c and C17â:â0 as the major fatty acids (>5â%). The DNA G+C content of the genomes was determined to be 64.2 mol% for strain T2T and 64.4 mol% for strain T5. The DNA-DNA hybridization values of strains T2T and T5 with B.aquatica PE 4-5T, B. natatoria DSM 3183T, and B. ursincola KR-99T were 19.7-42.4â%. Based on the combined genotypic and phenotypic data, we propose that strains T2T and T5 represent a novel species of the genus Blastomonas, for which the name Blastomonas fulvasp. nov. is proposed. The type strain is T2T (=KCTC 42354T=JCM 30467T).
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Microcystis , Filogenia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Ubiquinona/químicaRESUMO
Dermal papilla (DP) is a pivotal part of hair follicle, and the smaller size of the DP is related with the hair loss. In this study, we investigated the effect of titrated extract of Centella asiatica (TECA) on hair growth inductive property on 3D spheroid cultured human DP cells (HDP cells). Significantly increased effect of TECA on cell viability was only shown in 3D sphered HPD cells, not in 2D cultured HDP cells. Also, TECA treatment increased the sphere size of HDP cells. The luciferase activity of STAT reporter genes and the expression of STAT-targeted genes, SOCS1 and SOCS3, were significantly decreased. Also, TECA treatment increased the expression of the hair growth-related signature genes in 3D sphered HDP cells. Furthermore, TECA led to downregulation of the level of phosphorylated STAT proteins in 3D sphered HDP cells. Overall, TECA activates the potential of hair inductive capacity in HDP cells.
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Centella/química , Derme/citologia , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Esferoides Celulares/citologia , Esferoides Celulares/metabolismoRESUMO
Charge carriers typically move faster in crystalline regions than in amorphous regions in conjugated polymers because polymer chains adopt a regular arrangement resulting in a high degree of π-π stacking in crystalline regions. In contrast, the random polymer chain orientation in amorphous regions hinders connectivity between conjugated backbones; thus, it hinders charge carrier delocalization. Various studies have attempted to enhance charge carrier transport by increasing crystallinity. However, these approaches are inevitably limited by the semicrystalline nature of conjugated polymers. Moreover, high-crystallinity conjugated polymers have proven inadequate for soft electronics applications because of their poor mechanical resilience. Increasing the polymer chain connectivity by forming localized aggregates via π-orbital overlap among several conjugated backbones in amorphous regions provides a more effective approach to efficient charge carrier transport. A simple strategy relying on the density of random copolymer alkyl side chains was developed to generate these localized aggregates. In this strategy, steric hindrance caused by these side chains was modulated to change their density. Interestingly, a random polymer exhibiting low alkyl side chain density and crystallinity displayed greatly enhanced field-effect mobility (1.37 cm(2)/(V·s)) compared with highly crystalline poly(3-hexylthiophene).
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The positioning of the nucleosome by ATP-dependent remodellers provides the fundamental chromatin environment for the regulation of diverse cellular processes acting on the underlying DNA. Recently, genome-wide nucleosome mapping has revealed more detailed information on the chromatin-remodelling factors. Here, we report that the Schizosaccharomyces pombe CHD remodeller, Hrp3, is a global regulator that drives proper nucleosome positioning and nucleosome stability. The loss of Hrp3 resulted in nucleosome perturbation across the chromosome, and the production of antisense transcripts in the hrp3Δ cells emphasized the importance of nucleosome architecture for proper transcription. Notably, perturbation of the nucleosome in hrp3 deletion mutant was also associated with destabilization of the DNA-histone interaction and cell cycle-dependent alleviation of heterochromatin silencing. Furthermore, the effect of Hrp3 in the pericentric region was found to be accomplished via a physical interaction with Swi6, and appeared to cooperate with other heterochromatin factors for gene silencing. Taken together, our data indicate that a well-positioned nucleosome by Hrp3 is important for the spatial-temporal control of transcription-associated processes.