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1.
Nature ; 608(7924): 757-765, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948641

RESUMO

The notion that mobile units of nucleic acid known as transposable elements can operate as genomic controlling elements was put forward over six decades ago1,2. However, it was not until the advancement of genomic sequencing technologies that the abundance and repertoire of transposable elements were revealed, and they are now known to constitute up to two-thirds of mammalian genomes3,4. The presence of DNA regulatory regions including promoters, enhancers and transcription-factor-binding sites within transposable elements5-8 has led to the hypothesis that transposable elements have been co-opted to regulate mammalian gene expression and cell phenotype8-14. Mammalian transposable elements include recent acquisitions and ancient transposable elements that have been maintained in the genome over evolutionary time. The presence of ancient conserved transposable elements correlates positively with the likelihood of a regulatory function, but functional validation remains an essential step to identify transposable element insertions that have a positive effect on fitness. Here we show that CRISPR-Cas9-mediated deletion of a transposable element-namely the LINE-1 retrotransposon Lx9c11-in mice results in an exaggerated and lethal immune response to virus infection. Lx9c11 is critical for the neogenesis of a non-coding RNA (Lx9c11-RegoS) that regulates genes of the Schlafen family, reduces the hyperinflammatory phenotype and rescues lethality in virus-infected Lx9c11-/- mice. These findings provide evidence that a transposable element can control the immune system to favour host survival during virus infection.


Assuntos
Elementos de DNA Transponíveis , Interações entre Hospedeiro e Microrganismos , Imunidade , Retroelementos , Viroses , Animais , Sistemas CRISPR-Cas/genética , Elementos de DNA Transponíveis/genética , Elementos de DNA Transponíveis/imunologia , Evolução Molecular , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/imunologia , Imunidade/genética , Camundongos , RNA não Traduzido/genética , Sequências Reguladoras de Ácido Nucleico/genética , Retroelementos/genética , Retroelementos/imunologia , Viroses/genética , Viroses/imunologia
2.
Chem Rev ; 124(5): 2138-2204, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38421811

RESUMO

Interfacial engineering has long been a vital means of improving thin-film device performance, especially for organic electronics, perovskites, and hybrid devices. It greatly facilitates the fabrication and performance of solution-processed thin-film devices, including organic field effect transistors (OFETs), organic solar cells (OSCs), perovskite solar cells (PVSCs), and organic light-emitting diodes (OLEDs). However, due to the limitation of traditional interfacial materials, further progress of these thin-film devices is hampered particularly in terms of stability, flexibility, and sensitivity. The deadlock has gradually been broken through the development of self-assembled monolayers (SAMs), which possess distinct benefits in transparency, diversity, stability, sensitivity, selectivity, and surface passivation ability. In this review, we first showed the evolution of SAMs, elucidating their working mechanisms and structure-property relationships by assessing a wide range of SAM materials reported to date. A comprehensive comparison of various SAM growth, fabrication, and characterization methods was presented to help readers interested in applying SAM to their works. Moreover, the recent progress of the SAM design and applications in mainstream thin-film electronic devices, including OFETs, OSCs, PVSCs and OLEDs, was summarized. Finally, an outlook and prospects section summarizes the major challenges for the further development of SAMs used in thin-film devices.

3.
J Proteome Res ; 23(4): 1360-1369, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38457694

RESUMO

Trypsin is the gold-standard protease in bottom-up proteomics, but many sequence stretches of the proteome are inaccessible to trypsin and standard LC-MS approaches. Thus, multienzyme strategies are used to maximize sequence coverage in post-translational modification profiling. We present fast and robust SP3- and STRAP-based protocols for the broad-specificity proteases subtilisin, proteinase K, and thermolysin. All three enzymes are remarkably fast, producing near-complete digests in 1-5 min, and cost 200-1000× less than proteomics-grade trypsin. Using FragPipe resolved a major challenge by drastically reducing the duration of the required "unspecific" searches. In-depth analyses of proteinase K, subtilisin, and thermolysin Jurkat digests identified 7374, 8178, and 8753 unique proteins with average sequence coverages of 21, 29, and 37%, including 10,000s of amino acids not reported in PeptideAtlas' >2400 experiments. While we could not identify distinct cleavage patterns, machine learning could distinguish true protease products from random cleavages, potentially enabling the prediction of cleavage products. Finally, proteinase K, subtilisin, and thermolysin enabled label-free quantitation of 3111, 3659, and 4196 unique Jurkat proteins, which in our hands is comparable to trypsin. Our data demonstrate that broad-specificity proteases enable quantitative proteomics of uncharted areas of the proteome. Their fast kinetics may allow "on-the-fly" digestion of samples in the future.


Assuntos
Peptídeo Hidrolases , Proteômica , Peptídeo Hidrolases/metabolismo , Tripsina/metabolismo , Proteoma/análise , Endopeptidase K , Termolisina , Subtilisinas
4.
Langmuir ; 40(9): 4772-4778, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38381871

RESUMO

Self-assembled monolayers (SAMs) emerging as promising hole-selective layers (HSLs) are advantageous for facile processability, low cost, and minimal material consumption in the fabrication of both perovskite solar cells (PSCs) and organic solar cells (OSCs). However, owing to the different nature between perovskites and organic semiconductors, few SAMs were reported to effectively accommodate both PSCs and OSCs at the same time. In this regard, a universally applicable SAM that can accommodate both perovskites and organic semiconductors could be desirable for simplifying cell manufacturing, especially from an industrial perspective. In this work, we designed a SAM, TDPA-Cl by introducing chlorinated phenothiazine as the headgroup and linking with anchor phosphonic acid through a butyl chain. The resulting dense SAM was carefully characterized in terms of molecular bonding, surface morphology, and packing density, and its functions in OSCs and PSCs were discussed from the aspects of interactions with the absorber layer, energy level alignment, and charge-selective dipoles. The PM6:Y6-based OSCs with TDPA-Cl SAM as the HSL showed a superior performance to those with PEDOT:PSS. Furthermore, the universality was proved with an efficiency of 17.4% in the D18:Y6 system. In PSCs, the TDPA-Cl-based devices delivered a better performance of 22.4% than the PTAA-based devices (20.8%) with improved processability and reproducibility. This work represents a SAM with reasonably good compromise between the differing requirements of OSCs and PSCs.

5.
Chem Rev ; 122(18): 14180-14274, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-35929847

RESUMO

Organic photovoltaics (OPVs) have progressed steadily through three stages of photoactive materials development: (i) use of poly(3-hexylthiophene) and fullerene-based acceptors (FAs) for optimizing bulk heterojunctions; (ii) development of new donors to better match with FAs; (iii) development of non-fullerene acceptors (NFAs). The development and application of NFAs with an A-D-A configuration (where A = acceptor and D = donor) has enabled devices to have efficient charge generation and small energy losses (Eloss < 0.6 eV), resulting in substantially higher power conversion efficiencies (PCEs) than FA-based devices. The discovery of Y6-type acceptors (Y6 = 2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]-thiadiazolo[3,4-e]-thieno[2″,3″:4',5']thieno-[2',3':4,5]pyrrolo-[3,2-g]thieno-[2',3':4,5]thieno-[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile) with an A-DA' D-A configuration has further propelled the PCEs to go beyond 15% due to smaller Eloss values (∼0.5 eV) and higher external quantum efficiencies. Subsequently, the PCEs of Y6-series single-junction devices have increased to >19% and may soon approach 20%. This review provides an update of recent progress of OPV in the following aspects: developments of novel NFAs and donors, understanding of the structure-property relationships and underlying mechanisms of state-of-the-art OPVs, and tasks underpinning the commercialization of OPVs, such as device stability, module development, potential applications, and high-throughput manufacturing. Finally, an outlook and prospects section summarizes the remaining challenges for the further development of OPV technology.

6.
J Cell Mol Med ; 27(1): 127-140, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36528873

RESUMO

Follistatin (FST) and activin A as gonadal proteins exhibit opposite effects on follicle-stimulating hormone (FSH) release from pituitary gland, and activin A-FST system is involved in regulation of decidualization in reproductive biology. However, the roles of FST and activin A in migration of decidualized endometrial stromal cells are not well characterized. In this study, transwell chambers and microfluidic devices were used to assess the effects of FST and activin A on migration of decidualized mouse endometrial stromal cells (d-MESCs). We found that compared with activin A, FST exerted more significant effects on adhesion, wound healing and migration of d-MESCs. Similar results were also seen in the primary cultured decidual stromal cells (DSCs) from uterus of pregnant mouse. Simultaneously, the results revealed that FST increased calcium influx and upregulated the expression levels of the migration-related proteins MMP9 and Ezrin in d-MESCs. In addition, FST increased the level of phosphorylation of JNK in d-MESCs, and JNK inhibitor AS601245 significantly attenuated FST action on inducing migration of d-MESCs. These data suggest that FST, not activin A in activin A-FST system, is a crucial chemoattractant for migration of d-MESCs by JNK signalling to facilitate the successful uterine decidualization and tissue remodelling during pregnancy.


Assuntos
Movimento Celular , Endométrio , Folistatina , Sistema de Sinalização das MAP Quinases , Animais , Feminino , Camundongos , Gravidez , Movimento Celular/fisiologia , Hormônio Foliculoestimulante/metabolismo , Folistatina/genética , Folistatina/metabolismo , Células Estromais/metabolismo , Útero/metabolismo , Endométrio/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia
7.
J Am Chem Soc ; 145(10): 5920-5929, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36877962

RESUMO

Functional additives that can interact with the perovskite precursors to form the intermediate phase have been proven essential in obtaining uniform and stable α-FAPbI3 films. Among them, Cl-based volatile additives are the most prevalent in the literature. However, their exact role is still unclear, especially in inverted perovskite solar cells (PSCs). In this work, we have systematically studied the functions of Cl-based volatile additives and MA-based additives in formamidinium lead iodide (FAPbI3)-based inverted PSCs. Using in situ photoluminescence, we provide clear evidence to unravel the different roles of volatile additives (NH4Cl, FACl, and MACl) and MA-based additives (MACl, MABr, and MAI) in the nucleation, crystallization, and phase transition of FAPbI3. Three different kinds of crystallization routes are proposed based on the above additives. The non-MA volatile additives (NH4Cl and FACl) were found to promote crystallization and lower the phase-transition temperatures. The MA-based additives could quickly induce MA-rich nuclei to form pure α-phase FAPbI3 and dramatically reduce phase-transition temperatures. Furthermore, volatile MACl provides a unique effect on promoting the growth of secondary crystallization during annealing. The optimized solar cells with MACl can achieve an efficiency of 23.1%, which is the highest in inverted FAPbI3-based PSCs.

8.
J Am Chem Soc ; 145(10): 5909-5919, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36877211

RESUMO

Organic photovoltaics (OPVs) have achieved great progress in recent years due to delicately designed non-fullerene acceptors (NFAs). Compared with tailoring of the aromatic heterocycles on the NFA backbone, the incorporation of conjugated side-groups is a cost-effective way to improve the photoelectrical properties of NFAs. However, the modifications of side-groups also need to consider their effects on device stability since the molecular planarity changes induced by side-groups are related to the NFA aggregation and the evolution of the blend morphology under stresses. Herein, a new class of NFAs with local-isomerized conjugated side-groups are developed and the impact of local isomerization on their geometries and device performance/stability are systematically investigated. The device based on one of the isomers with balanced side- and terminal-group torsion angles can deliver an impressive power conversion efficiency (PCE) of 18.5%, with a low energy loss (0.528 V) and an excellent photo- and thermal stability. A similar approach can also be applied to another polymer donor to achieve an even higher PCE of 18.8%, which is among the highest efficiencies obtained for binary OPVs. This work demonstrates the effectiveness of applying local isomerization to fine-tune the side-group steric effect and non-covalent interactions between side-group and backbone, therefore improving both photovoltaic performance and stability of fused ring NFA-based OPVs.

9.
Angew Chem Int Ed Engl ; 62(21): e202303066, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36946862

RESUMO

Organic solar cells (OSCs) have advanced rapidly due to the development of new photovoltaic materials. However, the long-term stability of OSCs still poses a severe challenge for their commercial deployment. To address this issue, a dimer acceptor (dT9TBO) with flexible linker is developed for incorporation into small-molecule acceptors to form molecular alloy with enhanced intermolecular packing and suppressed molecular diffusion to stabilize active layer morphology. Consequently, the PM6 : Y6 : dT9TBO-based device displays an improved power conversion efficiency (PCE) of 18.41 % with excellent thermal stability and negligible decay after being aged at 65 °C for 1800 h. Moreover, the PM6 : Y6 : dT9TBO-based flexible OSC also exhibits excellent mechanical durability, maintaining 95 % of its initial PCE after being bended repetitively for 1500 cycles. This work provides a simple and effective way to fine-tune the molecular packing with stabilized morphology to overcome the trade-off between OSC efficiency and stability.

10.
Angew Chem Int Ed Engl ; 62(46): e202311559, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37792667

RESUMO

Organic photovoltaics (OPV) are one of the most effective ways to harvest renewable solar energy, with the power conversion efficiency (PCE) of the devices soaring above 19 % when processed with halogenated solvents. The superior photocurrent of OPV over other emerging photovoltaics offers more opportunities to further improve the efficiency. Tailoring the absorption band of photoactive materials is an effective way to further enhance OPV photocurrent. However, the field has mostly been focusing on improving the near-infrared region photo-response, with the absorption shoulders in short-wavelength region (SWR) usually being neglected. Herein, by developing a series of non-fullerene acceptors (NFAs) with varied side-group conjugations, we observe an enhanced SWR absorption band with increased side-group conjugation length. The underpinning factors of how molecular structures and geometries improve SWR absorption are clearly elucidated through theoretical modelling and crystallography. Moreover, a clear relationship between the enhanced SWR absorption and reduced singlet-triplet energy gap is established, both of which are favorable for the OPV performance and can be tailored by rational structure design of NFAs. Finally, the rationally designed NFA, BO-TTBr, affords a decent PCE of 18.5 % when processed with a non-halogenated green solvent.

11.
Acc Chem Res ; 54(20): 3906-3916, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34606230

RESUMO

ConspectusOrganic photovoltaics (OPVs) with a photoactive layer containing a blend of organic donor and acceptor species are considered to be a promising technology for clean energy owing to their unique flexible form factor and good solution processability that can potentially address the scalability challenges. The delicate designs of both donors and acceptors have significantly enhanced the power conversion efficiency of OPVs to more than 18%. Nonfullerene small-molecule acceptors (NFAs) have played a critical role in enhancing the short-circuit current density (JSC) by efficiently harvesting near-infrared (NIR) sunlight. To take full advantage of the abundant NIR photons, the optical band gap of NFAs should be further reduced to improve the performance of OPVs. Incorporating highly polarizable selenium atoms onto the backbone of organic conjugated materials has been proven to be an effective way to decrease their optical band gap. For example, a selenium-substituted NFA recently developed by our group has attained a JSC of approximate 27.5 mA cm-2 in OPV devices, surpassing those of most emerging photovoltaic systems. Inspired by this advance, we concentrate on the topic of selenium-containing materials in this Account to incite readers' interest in further exploring this series of materials.In this Account, we first compare the differences among chalcogen heterocycles and discuss the influence of fundamental electronic behavior on the collective photoelectrical properties of the resulting materials. The superior features of selenium-substituted materials are summarized as follows: (1) The large covalent radius of selenium can diminish the π-orbital overlap, rendering enhanced quinoidal resonance character and a narrowed optical band gap of resulting materials. (2) The selenium atom is more polarizable than sulfur owing to its larger and looser outermost electron cloud, enabling enhanced intermolecular Se-Se interaction and increased charge carrier mobility of relevant materials in the solid state. We then focus on summarizing the design rules for various categories of selenium-containing materials including polymer donors, small-molecule acceptors, and polymer acceptors, especially those composed of ladder-type polycyclic units. The motivation for incorporating selenium atoms into these materials and the structure-property relationships were thoroughly elucidated. Specifically, we discuss the changes in the optical band gap, charge carrier mobility, and molecular packing induced by selenium substitution and correlate the effects of these changes with the exciton behaviors, energy loss, and nanoscale film morphology of corresponding OPV devices. Furthermore, we point out the intrinsic stability of selenium-containing materials under maximum-power-point tracking and long-term photo- or thermostress and indicate their potential use in semitransparent and tandem solar cells. At the end, the prospect of future research focuses and the possible applications of selenium-containing materials in the OPV field are discussed.

12.
Macromol Rapid Commun ; 43(16): e2200062, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35318766

RESUMO

Recently, the strategy of polymerized small-molecule acceptors (PSMAs) has attracted extensive attention for applications in all-polymer solar cells (all-PSCs). Although side-chain engineering is considered as a simple and effective strategy for manipulating polymer properties, the corresponding effect on photovoltaic performance of PSMAs in all-PSCs has not been systemically investigated. Herein, a series of PSMAs based on the benzotriazole (BTz)-core fused SMAs with different N-alkyl chains including branched 2-butyloctyl, linear n-octyl, and methyl on the BTz unit, namely PZT-C12, PZT-C8, and PZT-C1, respectively, is presented. Comparative studies show that the size of alkyl chains has a significant impact on the solid-state behavior of PZT polymers, which in turn affects their light absorption and charge transporting capacities, and subsequently the all-PSC performances. When combining with the polymer donor PBDB-T, PZT-C1 affords a champion power conversion efficiency of 14.9%, compared to 13.1% of PZT-C12, and 13.8% of PZT-C8 in the resultant all-PSCs, mainly benefiting from its better crystallinity and the more favorable blend morphology. This work emphasizes the importance of optimizing side-chain substituents on PSMAs for improving the device efficiency of all-PSCs.

13.
Angew Chem Int Ed Engl ; 61(51): e202213560, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36300589

RESUMO

Carbazole-derived self-assembled monolayers (SAMs) are promising hole-selective materials for inverted perovskite solar cells (PSCs). However, they often possess small dipoles which prohibit them from effectively modulating the workfunction of ITO substrate, limiting the PSC photovoltage. Moreover, their properties can be drastically affected by even subtle structural modifications, undermining the final PSC performance. Here, we designed two carbazole-derived SAMs, CbzPh and CbzNaph through asymmetric or helical π-expansion for improved molecular dipole moment and strengthened π-π interaction. The helical π-expanded CbzNaph has the largest dipole, forming densely packed and ordered monolayer, facilitated by the highly ordered assembly observed in its π-scaffold's single crystal. These synergistically modulate the perovskite crystallization atop and tune the ITO workfunction. Consequently, the champion PSC employing CbzNaph showed an excellent 24.1 % efficiency and improved stability.

14.
Angew Chem Int Ed Engl ; 61(30): e202203088, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35560775

RESUMO

Self-assembled monolayers (SAMs) have been widely employed as an effective way to modify interfaces of electronic/optoelectronic devices. To achieve a good control of the growth and molecular functionality of SAMs, we develop a co-assembled monolayer (co-SAM) for obtaining efficient hole selection and suppressed recombination at the hole-selective interface in inverted perovskite solar cells (PSCs). By engineering the position of methoxy substituents, an aligned energy level and favorable dipole moment can be obtained in our newly synthesized SAM, ((2,7-dimethoxy-9H-carbazol-9-yl) methyl) phosphonic acid (DC-PA). An alkyl ammonium containing SAM is co-assembled to further optimize the surface functionalization and interaction with perovskite layer on top. A champion device with an excellent power conversion efficiency (PCE) of 23.59 % and improved device stability are achieved. This work demonstrates the advantage of using co-SAM in improving performance and stability of PSCs.

15.
Angew Chem Int Ed Engl ; 61(33): e202205168, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35736791

RESUMO

Intramolecular Cl-S non-covalent interaction is introduced to modify molecular backbone of a benzodithiophene terthiophene rhodamine (BTR) benchmark structure, helping planarize and rigidify the molecular framework for improving charge transport. Theoretical simulations and temperature-variable NMR experiments clearly validate the existence of Cl-S non-covalent interaction in two designed chlorinated donors and explain its important role in enhancing planarity and rigidity of the molecules for enhancing their crystallinity. The asymmetric isomerization of side-chains further optimizes the molecular orientation and surface energy to strike a balance between its crystallinity and miscibility. This carefully manipulated molecular design helps result in increased carrier mobility and suppressed charge recombination to obtain simultaneously enhanced short-circuit current (Jsc ) and fill factor (FF) and a very high efficiency of 15.73 % in binary all-small-molecule organic solar cells.

16.
J Am Chem Soc ; 143(7): 2665-2670, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33566603

RESUMO

Despite the significant progresses made in all-polymer solar cells (all-PSCs) recently, the relatively low short-circuit current density (Jsc) and large energy loss are still quite difficult to overcome for further development. To address these challenges, we developed a new class of narrow-bandgap polymer acceptors incorporating a benzotriazole (BTz)-core fused-ring segment, named the PZT series. Compared to the commonly used benzothiadiazole (BT)-containing polymer PYT, the less electron-deficient BTz renders PZT derivatives with significantly red-shifted optical absorption and up-shifted energy levels, leading to simultaneously improved Jsc and open-circuit voltage in the resultant all-PSCs. More importantly, a regioregular PZT (PZT-γ) has been developed to achieve higher regiospecificity for avoiding the formation of isomers during polymerization. Benefiting from the more extended absorption, better backbone ordering, and more optimal blend morphology with donor component, PZT-γ-based all-PSCs exhibit a record-high power conversion efficiency of 15.8% with a greatly enhanced Jsc of 24.7 mA/cm2 and a low energy loss of 0.51 eV.

17.
Angew Chem Int Ed Engl ; 60(29): 15935-15943, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33939259

RESUMO

All-polymer solar cells (all-PSCs) progressed tremendously due to recent advances in polymerized small molecule acceptors (PSMAs), and their power conversion efficiencies (PCEs) have exceeded 15 %. However, the practical applications of all-PSCs are still restricted by a lack of PSMAs with a broad absorption, high electron mobility, low energy loss, and good batch-to-batch reproducibility. A multi-selenophene-containing PSMA, PFY-3Se, was developed based on a selenophene-fused SMA framework and a selenophene π-spacer. Compared to its thiophene analogue PFY-0Se, PFY-3Se shows a ≈30 nm red-shifted absorption, increased electron mobility, and improved intermolecular interaction. In all-PSCs, PFY-3Se achieved an impressive PCE of 15.1 % with both high short-circuit current density of 23.6 mA cm-2 and high fill factor of 0.737, and a low energy loss, which are among the best values in all-PSCs reported to date and much better than PFY-0Se (PCE=13.0 %). Notably, PFY-3Se maintains similarly good batch-to-batch properties for realizing reproducible device performance, which is the first reported and also very rare for the PSMAs. Moreover, the PFY-3Se-based all-PSCs show low dependence of PCE on device area (0.045-1.0 cm2 ) and active layer thickness (110-250 nm), indicating the great potential toward practical applications.

18.
Angew Chem Int Ed Engl ; 60(37): 20437-20442, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34227199

RESUMO

Delicately designed dopant-free hole-transporting materials (HTMs) with ordered structure have become one of the major strategies to achieve high-performance perovskite solar cells (PSCs). In this work, we report two donor-π linker-donor (D-π-D) HTMs, N01 and N02, which consist of facilely synthesized 4,8-di(n-hexyloxy)-benzo[1,2-b:4,5-b']dithiophene as a π linker, with 10-bromohexyl-10H-phenoxazine and 10-hexyl-10H-phenoxazine as donors, respectively. The N01 molecules form a two-dimensional conjugated network governed by C-H⋅⋅⋅O and C-H⋅⋅⋅Br interaction between phenoxazine donors, and synchronously construct a three-dimension lamellar structure with the aid of interlaminar π-π interaction. Consequently, N01 as a dopant-free small-molecule HTM exhibits a higher intrinsic hole mobility and more favorable interfacial properties for hole transport, hole extraction and perovskite growth, enabling an inverted PSC to achieve a very impressive power conversion efficiency of 21.85 %.

19.
Am J Physiol Cell Physiol ; 319(1): C75-C92, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32348173

RESUMO

Cell migration is central to development, wound healing, tissue regeneration, and immunity. Despite extensive knowledge of muscle regeneration, myoblast migration during regeneration is not well understood. C2C12 mouse myoblast migration and morphology were investigated using a triple-docking polydimethylsiloxane-based microfluidic device in which cells moved under gravity-driven laminar flow on uniform (=) collagen (CN=), fibronectin (FN=), or opposing gradients (CN-FN or FN-CN). In haptotaxis experiments, migration was faster on FN= than on CN=. At 10 h, cells were more elongated on FN-CN and migration was faster than on the CN-FN substrate. Net migration distance on FN-CN at 10 h was greater than on CN-FN, as cells rapidly entered the channel as a larger population (bulk-cell movement, wave 1). Hepatocyte growth factor (HGF) stimulated rapid chemotaxis on FN= but not CN=, increasing migration speed at 10 h early in the channel at low HGF in a steep HGF gradient. HGF accelerated migration on FN= and bulk-cell movement on both uniform substrates. An HGF gradient also slowed cells in wave 2 moving on FN-CN, not CN-FN. Both opposing-gradient substrates affected the shape, speed, and net distance of migrating cells. Gradient and uniform configurations of HGF and substrate differentially influenced migration behavior. Therefore, haptotaxis substrate configuration potently modifies myoblast chemotaxis by HGF. Innovative microfluidic experiments advance our understanding of intricate complexities of myoblast migration. Findings can be leveraged to engineer muscle-tissue volumes for transplantation after serious injury. New analytical approaches may generate broader insights into cell migration.


Assuntos
Quimiotaxia/fisiologia , Colágeno/metabolismo , Fibronectinas/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Microfluídica/métodos , Mioblastos/fisiologia , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Quimiotaxia/efeitos dos fármacos , Colágeno/administração & dosagem , Fibronectinas/administração & dosagem , Fator de Crescimento de Hepatócito/administração & dosagem , Humanos , Camundongos , Mioblastos/efeitos dos fármacos
20.
J Am Chem Soc ; 142(36): 15246-15251, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32830487

RESUMO

Understanding the molecular structure and self-assembly of thiadiazole-derived non-fullerene acceptors (NFAs) is very critical for elucidating the origin of their extraordinary charge generation and transport properties that enable high power conversion efficiencies to be achieved in these systems. A comprehensive crystallographic study on a state-of-the-art NFA, Y6, and its selenium analog, CH1007, has been conducted which revealed that the face-to-face π-core interaction induced by benzo[2,1,3]thiadiazole S-N-containing moieties plays a significant role in governing the molecular geometries and unique packing of Y6 and CH1007 to ensure their superior charge-transport properties. Moreover, benefitting from the red-shifted optical absorption via selenium substitution, photovoltaic devices based on a PM6:CH1007:PC71BM ternary blend delivered an exceptionally high short-circuit current of 27.48 mA/cm2 and a power conversion efficiency of 17.08%.

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