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A series of new small-molecule acceptors-NA9, NA10, and NA11-based on benzo[ b ]phenazine are synthesized. The chlorinated NA10 and brominated NA11 exhibit improved molecular packing and enhanced charge transport, resulting in higher power conversion efficiencies (PCEs) of 15.65% and 16.64%, respectively, compared to 11.66% for the non-halogenated NA9. These results underscore the great potential of peripheral halogenation particularly bromination, in achieving high-performance OSCs.

The advancement of acceptors plays a pivotal role in determining photovoltaic performance. While previous efforts have focused on optimizing acceptor-donor-acceptor 1 -donor-acceptor (A-DA 1 -D-A)-typed acceptors by adjusting side chains, end groups, and conjugated extension of the electron-deficient central A 1 unit, the systematic exploration of the impact of peripheral aryl substitutions, particularly with different electron groups, on the A 1 unit and its influence on device performance is still lacking. In this study, three novel acceptors - QxTh, QxPh, and QxPy - with distinct substitutions on the quinoxaline (Qx) are designed and synthesized. Density functional theory (DFT) analyses reveal that QxPh, featuring a phenyl-substituted Qx, exhibits the smallest molecular binding energies and a tightest π···π stacking distance. Consequently, the PM6:QxPh device demonstrates a better power conversion efficiency (PCE) of 17.1% compared to the blends incorporating QxTh (16.4%) and QxPy (15.7%). This enhancement is primarily attributed to suppressed charge recombination, improved charge extraction, and more favorable molecular stacking and morphology. Importantly, introducing QxPh as a guest acceptor into the PM6:BTP-eC9 binary system yields an outstanding PCE of 19.5%, indicating the substantial potential of QxPh in advancing ternary device performance. The work provides deep insights into the expansion of high-performance organic photovoltaic materials through peripheral aryl substitution strategy., (© 2024 Wiley‐VCH GmbH.)

High-performance organic solar cells often rely on halogen-containing solvents, which restrict the photovoltaic industry. Therefore, it is imperative to develop efficient organic photovoltaic materials compatible with halogen-free solvents. Herein, a series of benzo[a]phenazine (BP)-core-based small-molecule acceptors (SMAs) achieved through an isomerization chlorination strategy is presented, comprising unchlorinated NA1, 10-chlorine substituted NA2, 8-chlorine substituted NA3, and 7-chlorine substituted NA4. Theoretical simulations highlight NA3's superior orbit overlap length and tight molecular packing, attributed to interactions between the end group and BP unit. Furthermore, NA3 demonstrates dense 3D network structures and a record electronic coupling of 104.5 meV. These characteristics empower the ortho-xylene (o-XY) processed PM6:NA3 device with superior power conversion efficiency (PCE) of 18.94%, surpassing PM6:NA1 (15.34%), PM6:NA2 (7.18%), and PM6:NA4 (16.02%). Notably, the significantly lower PCE in the PM6:NA2 device is attributed to excessive self-aggregation characteristics of NA2 in o-XY. Importantly, the incorporation of D18-Cl into the PM6:NA3 binary blend enhances crystallographic ordering and increases the exciton diffusion length of the donor phase, resulting in a ternary device efficiency of 19.75% (certified as 19.39%). These findings underscore the significance of incorporating new electron-deficient units in the design of efficient SMAs tailored for environmentally benign solvent processing of OSCs., (© 2024 Wiley‐VCH GmbH.)

Developing a new end group for synthesizing asymmetric small molecule acceptors (SMAs) is crucial for achieving high-performance organic photovoltaics (OPVs). Herein, an asymmetric small molecule acceptor, BTP-BO-4FO, featuring a new difluoro-methoxylated end-group is reported. Compared to its symmetric counterpart L8-BO, BTP-BO-4FO exhibits an upshifted energy level, larger dipole moment, and more sequential crystallinity. By adopting two representative and widely available solvent additives (1-chloronaphthalene (CN) and 1,8-diiodooctane (DIO)), the device based on PM6:BTP-BO-4FO (CN) photovoltaic blend demonstrates a power conversion efficiency (PCE) of 18.62% with an excellent open-circuit voltage (V OC ) of 0.933 V, which surpasses the optimal result of L8-BO. The PCE of 18.62% realizes the best efficiencies for binary OPVs based on SMAs with asymmetric end groups. A series of investigations reveal that optimized PM6:BTP-BO-4FO film demonstrates similar molecular packing motif and fibrillar phase distribution as PM6:L8-BO (DIO) does, resulting in comparable recombination dynamics, thus, similar fill factor. Besides, it is found PM6:BTP-BO-4FO possesses more efficient charge generation, which yields better V OC -J SC balance. This study provides a new ending group that enables a cutting-edge efficiency in asymmetric SMA-based OPVs, enriching the material library and shed light on further design ideas., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Background: This study aimed to investigate the knowledge, attitudes, and practices (KAP) toward cardiovascular complications among end-stage renal disease patients undergoing maintenance hemodialysis., Methods: This web-based cross-sectional study was conducted at Guangdong Provincial People's Hospital between December 2022, and May 2023., Results: A total of 545 valid questionnaires were collected, with an average age of 57.72 ± 13.47 years. The mean knowledge, attitudes and practices scores were 8.17 ± 2.9 (possible range: 0-24), 37.63 ± 3.80 (possible range: 10-50), 33.07 ± 6.10 (possible range: 10-50) respectively. Multivariate logistic regression analysis showed that patients from non-urban area had lower knowledge compared to those from urban area (odds ratio (OR) = 0.411, 95% CI: 0.262-0.644, P < 0.001). Furthermore, higher levels of education were associated with better knowledge, as indicated by OR for college and above (OR = 4.858, 95% CI: 2.483-9.504), high school/vocational school (OR = 3.457, 95% CI: 1.930-6.192), junior high school (OR = 3.300, 95% CI: 1.945-5.598), with primary school and below as reference group (all P < 0.001). Besides, better knowledge (OR = 1.220, 95% CI: 1.132-1.316, P < 0.001) and higher educational levels were independently associated with positive attitudes. Specifically, individuals with a college degree and above (OR = 2.986, 95% CI: 1.411-6.321, P = 0.004) and those with high school/vocational school education (OR = 2.418, 95% CI: 1.314-4.451, P = 0.005) have more positive attitude, with primary school and below as reference group. Next, better attitude (OR = 1.174, 95% CI: 1.107-1.246, P < 0.001) and higher education were independently associated with proactive practices. Those with college and above (OR = 2.870, 95% CI: 1.359-6.059, P = 0.006), and those with high school/vocational school education (OR = 1.886, 95% CI: 1.032-3.447, P = 0.039) had more proactive practices, with primary school and below as reference group., Conclusions: End-stage renal disease patients undergoing maintenance hemodialysis demonstrated insufficient knowledge, positive attitudes, and moderate practices regarding cardiovascular complications. Targeted interventions should prioritize improving knowledge and attitudes, particularly among patients with lower educational levels and income, to enhance the management of cardiovascular complications in end-stage renal disease., (© 2024. The Author(s).)

Utilizing intermolecular hydrogen-bonding interactions stands for an effective approach in advancing the efficiency and stability of small-molecule acceptors (SMAs) for polymer solar cells. Herein, we synthesized three SMAs (Qo1, Qo2, and Qo3) using indeno[1,2-b]quinoxalin-11-one (Qox) as the electron-deficient group, with the incorporation of a methylation strategy. Through crystallographic analysis, it is observed that two Qox-based methylated acceptors (Qo2 and Qo3) exhibit multiple hydrogen bond-assisted 3D network transport structures, in contrast to the 2D transport structure observed in gem-dichlorinated counterpart (Qo4). Notably, Qo2 exhibits multiple and stronger hydrogen-bonding interactions compared with Qo3. Consequently, PM6 : Qo2 device realizes the highest power conversion efficiency (PCE) of 18.4 %, surpassing the efficiencies of devices based on Qo1 (15.8 %), Qo3 (16.7 %), and Qo4 (2.4 %). This remarkable PCE in PM6 : Qo2 device can be primarily ascribed to the enhanced donor-acceptor miscibility, more favorable medium structure, and more efficient charge transfer and collection behavior. Moreover, the PM6 : Qo2 device demonstrates exceptional thermal stability, retaining 82.8 % of its initial PCE after undergoing annealing at 65 °C for 250 hours. Our research showcases that precise methylation, particularly targeting the formation of intermolecular hydrogen-bonding interactions to tune crystal packing patterns, represents a promising strategy in the molecular design of efficient and stable SMAs., (© 2023 Wiley-VCH GmbH.)

With plenty of popular and effective ternary organic solar cells (OSCs) construction strategies proposed and applied, its power conversion efficiencies (PCEs) have come to a new level of over 19% in single-junction devices. However, previous studies are heavily based in chloroform (CF) leaving behind substantial knowledge deficiencies in understanding the influence of solvent choice when introducing a third component. Herein, we present a case where a newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy, named BTP-BO-3FO with enlarged bandgap, brings different morphological evolution and performance improvement effect on host system PM6:BTP-eC9, processed by CF and ortho-xylene (o-XY). With detailed analyses supported by a series of experiments, the best PCE of 19.24% for green solvent-processed OSCs is found to be a fruit of finely tuned crystalline ordering and general aggregation motif, which furthermore nourishes a favorable charge generation and recombination behavior. Likewise, over 19% PCE can be achieved by replacing spin-coating with blade coating for active layer deposition. This work focuses on understanding the commonly met yet frequently ignored issues when building ternary blends to demonstrate cutting-edge device performance, hence, will be instructive to other ternary OSC works in the future., (© 2023. The Author(s).)

The central core in A-DA 1 D-A-type small-molecule acceptor (SMAs) plays an important role in determining the efficiency of organic solar cells (OSCs), while the principles governing the efficient design of SMAs remain elusive. Herein, we developed a series of SMAs with pyrido[2,3-b]quinoxaline (PyQx) as new electron-deficient unit by combining with the cascade-chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. The introduction of chlorine atoms reduces the intramolecular charge transfer effects but elevates the LUMO values. Density functional theory (DFT) reveals that Py2 with ortho chlorine substituted PyQx and Py5 with two chlorine atoms yield larger dipole moments and smaller π⋅⋅⋅π stacking distances, as compared with the other three acceptors. Moreover, Py2 shows the strongest light absorption capability induced by extended orbit overlap lengths and more efficient packing structures in the dimers. These features endow the best device performance of Py2 due to the better molecular packing and aggregation behaviors, more suitable domain sizes with better exciton dissociation and charge recombination. This study highlights the significance of incorporating large dipole moments, small π⋅⋅⋅π stacking distances and extended orbit overlap lengths in dimers into the development of high-performance SMAs, providing insight into the design of efficient A-DA 1 D-A-type SMAs for OSCs., (© 2023 Wiley-VCH GmbH.)

Zinc depletion is associated with alcohol-associated liver injury. We tested the hypothesis that increasing zinc availability along with alcohol consumption prevents alcohol-associated liver injury. Zinc-glutathione (ZnGSH) was synthesized and directly added to Chinese Baijiu. Mice were administered a single gastric dose of 6 g/kg ethanol in Chinese Baijiu with or without ZnGSH. ZnGSH in Chinese Baijiu did not change the likeness of the drinkers but significantly reduced the recovery time from drunkenness along with elimination of high-dose mortality. ZnGSH in Chinese Baijiu decreased serum AST and ALT, suppressed steatosis and necrosis, and increased zinc and GSH concentrations in the liver. It also increased alcohol dehydrogenase and aldehyde dehydrogenase in the liver, stomach, and intestine and reduced acetaldehyde in the liver. Thus, ZnGSH in Chinese Baijiu prevents alcohol-associated liver injury by increasing alcohol metabolism timely with alcohol consumption, providing an alternative approach to the management of alcohol-associated drinking., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors.)

All-polymer solar cells (all-PSCs) are organic solar cells in which both the electron donor and the acceptor are polymers and are considered more promising in large-scale production. Thanks to the polymerizing small molecule acceptor strategy, the power conversion efficiency of all-PSCs has ushered in a leap in recent years. However, due to the electrical properties of polymerized small-molecule acceptors (PSMAs), the FF of the devices is generally not high. The typical electron transport material widely used in these devices is PNDIT-F3N, and it is a common strategy to improve the device fill factor (FF) through interface engineering. This work improves the efficiency of all-polymer solar cells through interfacial layer engineering. Using PDINN as the electron transport layer, we boost the FF of the devices from 69.21% to 72.05% and the power conversion efficiency (PCE) from 15.47% to 16.41%. This is the highest efficiency for a PY-IT-based binary all-polymer solar cell. This improvement is demonstrated in different all-polymer material systems.

Rationally utilizing and developing synthetic units is of particular significance for the design of high-performance non-fullerene small-molecule acceptors (SMAs). Here, a thieno[3 , 2- b ]pyrrole synthetic unit was employed to develop a set of SMAs (ThPy1, ThPy2, ThPy3 and ThPy4) by changing the number or the position of the pyrrole ring in the central core based on a standard SMA of IT-4Cl, compared to which the four thieno[3 , 2- b ]pyrrole-based acceptors exhibit bathochromic absorption and upshifted frontier orbital energy level due to the strong electron-donating ability of pyrrole. As a result, the polymer solar cells (PSCs) of the four thieno[3 , 2- b ]pyrrole-based acceptors yield higher open-circuit voltage and lower energy loss relative to those of the IT-4Cl-based device. What is more, the ThPy3-based device achieves a power conversion efficiency (PCE) (15.3%) and an outstanding fill factor (FF) (0.771) that are superior to the IT-4Cl-based device (PCE = 12.6%, FF = 0.758). The ThPy4-based device realizes the lowest energy loss and the smallest optical band gap, and the ternary PSC device based on PM6:BTP-eC9:ThPy4 exhibits a PCE of 18.43% and a FF of 0.802. Overall, this work sheds light on the great potential of thieno[3,2- b ]pyrrole-based SMAs in realizing low energy loss and high PCE., (© The Author(s) 2022. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

This work demonstrates a simple yet effective method to significantly improve the power conversion efficiency (PCE) of highly efficient non-fullerene organic solar cells by mixing two electron transport materials. The new electron transport layer shows an energy level better aligned with the active layer and an improved morphology that could reduce the active layer-electrode contact. These improvements lead to enhanced charge extraction, better charge selectivity, suppressed exciton recombination, and finally a boosted PCE in the PM6:Y6-based solar cells. When applied in conjunction with the non-halogenated solvent-processed PM6:PY-IT-based active layer, the mixed ETL also gives rise to a leading result for binary all-polymer solar cells (PCE of >16%) with a concurrent increase in V OC , J SC , and FF .

Soybean mosaic virus (SMV) is one of the most widespread and devastating viral diseases worldwide. The genetic architecture of qualitative resistance to SMV in soybean remains unclear. Here, the Rsvg2 locus was identified as underlying soybean resistance to SMV by genome-wide association and linkage analyses. Fine mapping results showed that soybean resistance to SMV strains G2 and G3 was controlled by a single dominant gene, GmST1, on chromosome 13, encoding a sulfotransferase (SOT). A key variation at position 506 in the coding region of GmST1 associated with the structure of the encoded SOT and changed SOT activity levels between RSVG2-S and RSVG2-R alleles. In RSVG2-S allele carrier "Hefeng25", the overexpression of GmST1 carrying the RSVG2-R allele from the SMV-resistant line "Dongnong93-046" conferred resistance to SMV strains G2 and G3. Compared to Hefeng25, the accumulation of SMV was decreased in transgenic plants carrying the RSVG2-R allele. SMV infection differentiated both the accumulation of jasmonates and expression patterns of genes involved in jasmonic acid (JA) signalling, biosynthesis and catabolism in RSVG2-R and RSVG2-S allele carriers. This characterization of GmST1 suggests a new scenario explaining soybean resistance to SMV., (© 2021 John Wiley & Sons Ltd.)

Many highly efficient all-polymer-based organic solar cells (OSCs) have been achieved owing to material design and device engineering. However, most of them were achieved by using halogenated solvents to process the active layers, being not beneficial to its nature of green energy technology. In this work, we compared chloroform- and toluene-processed PM6:PY-IT-based all-polymer devices with the same blend solution recipe, same film formation speed, and same postcast treatment. The film cast from toluene exhibited weaker crystallinity. For device performance, toluene enabled a better power conversion efficiency (PCE) of 15.51%, outperforming that of chloroform (15.00%), and it is the highest value for non-halogenated solvent-cast all-polymer-based OSCs to date. Toluene's morphology tuning effect was characterized to increase and balance the charge transport and then suppress the exciton recombination and improve the charge extraction, considered to be the reason for efficiency enhancement. Besides, the toluene-cast active layer-based devices showed slightly better photostability than the chloroform-driven ones. This work provided a new direction for building low-toxicity solvent-treated all-polymer OSCs with cutting-edge performance.

Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance of all-polymer solar cells (all-PSCs). Different from our recent work about fluoro- and bromo- co-modified end group of IC-FBr (a mixture of IC-FBr1 and IC-FBr2), in this paper, we synthesized and purified two regiospecific fluoro- and bromo- substituted end groups (IC-FBr-o & IC-FBr-m), which were then employed to construct two regio-regular polymer acceptors named PYF-T-o and PYF-T-m, respectively. In comparison with its isomeric counterparts named PYF-T-m with different conjugated coupling sites, PYF-T-o exhibits stronger and bathochromic absorption to achieve better photon harvesting. Meanwhile, PYF-T-o adopts more ordered inter-chain packing and suitable phase separation after blending with the donor polymer PM6, which resulted in suppressed charge recombination and efficient charge transport. Strikingly, we observed a dramatic performance difference between the two isomeric polymer acceptors PYF-T-o and PYF-T-m. While devices based on PM6:PYF-T-o can yield power conversion efficiency (PCE) of 15.2 %, devices based on PM6:PYF-T-m only show poor efficiencies of 1.4 %. This work demonstrates the success of configuration-unique fluorinated end groups in designing high-performance regular polymer acceptors, which provides guidelines towards developing all-PSCs with better efficiencies., (© 2021 Wiley-VCH GmbH.)

Recent advances in the development of polymerized A-D-A-type small-molecule acceptors (SMAs) have promoted the power conversion efficiency (PCE) of all-polymer solar cells (all-PSCs) over 13%. However, the monomer of an SMA typically consists of a mixture of three isomers due to the regio-isomeric brominated end groups (IC-Br(in) and IC-Br(out)). In this work, the two isomeric end groups are successfully separated, the regioisomeric issue is solved, and three polymer acceptors, named PY-IT, PY-OT, and PY-IOT, are developed, where PY-IOT is a random terpolymer with the same ratio of the two acceptors. Interestingly, from PY-OT, PY-IOT to PY-IT, the absorption edge gradually redshifts and electron mobility progressively increases. Theory calculation indicates that the LUMOs are distributed on the entire molecular backbone of PY-IT, contributing to the enhanced electron transport. Consequently, the PM6:PY-IT system achieves an excellent PCE of 15.05%, significantly higher than those for PY-OT (10.04%) and PY-IOT (12.12%). Morphological and device characterization reveals that the highest PCE for the PY-IT-based device is the fruit of enhanced absorption, more balanced charge transport, and favorable morphology. This work demonstrates that the site of polymerization on SMAs strongly affects device performance, offering insights into the development of efficient polymer acceptors for all-PSCs., (© 2020 Wiley-VCH GmbH.)

A non-conjugated polymer acceptor PF1-TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >10 5  cm -1 , a high LUMO level of -3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1-TS4-based all-PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1-TS4-based all-PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16-based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non-conjugated thioalkyl segments., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

Understanding the conformation effect on molecular packing, miscibility, and photovoltaic performance is important to open a new avenue for small-molecule acceptor (SMA) design. Herein, two novel acceptor-(donor-acceptor1-donor)-acceptor (A-DA1D-A)-type asymmetric SMAs are developed, namely C-shaped BDTP-4F and S-shaped BTDTP-4F. The BDTP-4F-based polymer solar cells (PSCs) with PM6 as donor, yields a power conversion efficiency (PCE) of 15.24%, significantly higher than that of the BTDTP-4F-based device (13.12%). The better PCE for BDTP-4F-based device is mainly attributed to more balanced charge transport, weaker bimolecular recombination, and more favorable morphology. Additionally, two traditional A-D-A-type SMAs (IDTP-4F and IDTTP-4F) are also synthesized to investigate the conformation effect on morphology and device performance. Different from the device result above, here, IDTP-4F with S-shape conformation outperforms than IDTTP-4F with C-shape conformation. Importantly, it is found that for these two different types of SMA, the better performing binary blend has similar morphological characteristics. Specifically, both PM6:BDTP-4F and PM6:IDTP-4F blend exhibit perfect nanofibril network structure with proper domain size, obvious face-on orientation and enhance donor-acceptor interactions, thereby better device performance. This work indicates tuning molecular conformation plays pivotal role in morphology and device effciciency, shining a light on the molecular design of the SMAs., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Novel cores for high performance nonfullerene acceptors (NFAs) remain to be developed. In this work, two new n-type nitrogen-containing organic heterocyclic NFAs, namely, BDTN-BF and BDTN-Th, were designed and synthesized based on a new seven fused-ring core (BDTN) with two different end-capping groups. As a result, BDTN-BF possessed similar absorption spectra in solution and solid state to BDTN-Th, but a slightly higher maximum molar extinction coefficient. Manufacturing the polymer solar cells with PM6 as the donor, the photovoltaic performance of BDTN-BF and BDTN-Th was investigated. The PM6:BDTN-BF-based device achieved the highest power conversion efficiency (PCE) of 11.54% with a high J sc of 20.20 mA cm -2 , a fill factor (FF) of 61.46%, and a large V oc of 0.93 V, and the energy loss ( E loss ) was calculated to be 0.48 eV. Comparatively, the PM6:BDTN-Th-based device achieved the maximum PCE value of only 3.53% because of inadequate J sc and FF. The higher J sc and FF for the PM6:BDTN-BF-based device was mainly due to the effective electron transfer from PM6 to BDTN-BF, more balanced μ h /μ e , higher electron mobility of the neat film, better charge collection and dissociation efficiency, and more favorable morphology. These results demonstrate that the acceptors with nearly identical absorption spectra could result in a significant difference in photovoltaic performance, which stress the importance of end-capping units. Furthermore, few NFA-based devices achieve large V oc and high J sc simultaneously as one based on PM6:BDTN-BF, indicating that nitrogen hybridization of NFAs may be an efficient strategy to realize high and balanced V oc and J sc .

The thermal stability of organic solar cells is critical for practical applications of this emerging technology. Thus, effective approaches and strategies need to be found to alleviate their inherent thermal instability. Here, we show a polymer acceptor-doping general strategy and report a thermally stable bulk heterojunction photovoltaic system, which exhibits an improved power conversion efficiency of 15.10%. Supported by statistical analyses of device degradation data, and morphological characteristics and physical mechanisms study, this polymer-doping blend shows a longer lifetime, nearly keeping its efficiency (t = 800 h) under accelerated aging tests at 150 o C. Further analysis of the degradation behaviors indicates a bright future of this system in outer space applications. Notably, the use of polymer acceptor as a dual function additive in the other four photovoltaic systems was also confirmed, demonstrating the good generality of this polymer-doping strategy.

Background: Developing an ideal wound dressing that meets the multiple demands of safe and practical, good biocompatibility, superior mechanical property and excellent antibacterial activity is highly desirable for wound healing. Bacterial cellulose (BC) is one of such promising class of biopolymers since it can control wound exudates and can provide moist environment to a wound resulting in better wound healing. However, the lack of antibacterial activity has limited its application., Methods and Results: We prepared a flexible dressing based on a bacterial cellulose membrane and then modified it by chemical crosslinking to prepare in situ synthesis of nZnO/BCM via a facile and eco-friendly approach. Scanning electron microscopy (SEM) results indicated that nZnO/BCM membranes were characterized by an ideal porous structure (pore size: 30~ 90 μm), forming a unique string-beaded morphology. The average water vapor transmission of nZnO/BCM was 2856.60 g/m 2 /day, which improved the moist environment of nZnO/BCM. ATR-FITR further confirmed the stepwise deposition of nano-zinc oxide. Tensile testing indicated that our nanocomposites were flexible, comfortable and resilient. Bacterial suspension assay and plate counting methods demonstrated that 5wt. % nZnO/BCM possessed excellent antibacterial activity against S.aureus and E. coli , while MTT assay demonstrated that they had no measurable cytotoxicity toward mammalian cells. Moreover, skin irritation test and histocompatibility examination supported that 5wt. % nZnO/BCM had no stimulation to skin and had acceptable biocompatibility with little infiltration of the inflammatory cells. Finally, by using a bacteria-infected ( S. aureus and E. coli ) murine wound model, we found that nZnO/BCM could prevent in vivo bacterial infections and promote wound healing via accelerating the re-epithelialization and wound contraction, and these membranes had no obvious toxicity toward normal tissues., Conclusion: Therefore, the constructed nZnO/BCM has great potential for biomedical applications as an efficient antibacterial wound dressing., Competing Interests: Prof. Dr. Hai Lin reports a patent for the preparation and application of bacterial cellulose wound dressing with anti-bacterial property licensed to 201510301459X. The authors report no other conflicts of interest in this work., (© 2020 Luo et al.)

Electron transport materials (ETM) play an important role in the improvement of efficiency and stability for inverted perovskite solar cells (PSCs). This work reports an efficient ETM, named PDI-C 60 , by the combination of perylene diimide (PDI) and fullerene. Compared to the traditional PCBM, this strategy endows PDI-C 60 with slightly shallower energy level and higher electron mobility. As a result, the device based on PDI-C 60 as electron transport layer (ETL) achieves high power conversion efficiency (PCE) of 18.6 %, which is significantly higher than those of the control devices of PCBM (16.6 %) and PDI (13.8 %). The high PCE of the PDI-C 60 -based device can be attributed to the more matching energy level with the perovskite, more efficient charge extraction, transport, and reduced recombination rate. To the best of our knowledge, the PCE of 18.6 % is the highest value in the PSCs using PDI derivatives as ETLs. Moreover, the device with PDI-C 60 as ETL exhibits better device stability due to the stronger hydrophobic properties of PDI-C 60 . The strategy using the PDI/fullerene hybrid provides insights for future molecular design of the efficient ETM for the inverted PSCs., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Increased extravascular lung water (EVLW) correlates with pulmonary morbidity and mortality in critical illness. The extravascular lung water index (EVLWI), which reflects the degree of EVLW in an individual, increases in the fluid reabsorption stage rather than the initial resuscitation stage in severe burn cases. While many factors contribute to EVLWI variation, the risk factors contributing to its abnormal elevation in severe burns remain unclear. The aim of this study was to identify the risk factors and associated limit values for abnormal elevation of EVLWI during the fluid reabsorption stage in a cohort of severely burned adults., Method: This prospective, single-center study included only adults with burn sizes≥50% of the total body surface area (TBSA) who were admitted within 24h after burn. Demographic data were collected, and transpulmonary thermodilution (TPTD) measurements and blood biochemistry tests were performed upon admission and up to day (PBD) 9. Risk factors for abnormal EVLWI were analyzed by logistic regression. Receiver operating characteristic (ROC) curves were constructed to determine the optimal cut-offs for each risk factor., Results: Seventy-two patients were ultimately enrolled, with a mean age of 40.3 years and mean burn size of 69.4% TBSA. EVLWI began to abnormally increase (>7ml/kg) on day 3 and up to PBD 9, indicating that a supranormal EVLWI developed in the fluid reabsorption stage. Several relevant factors were considered, including patient age, burn size, intrathoracic blood volume index (ITBVI), pulmonary vascular permeability index (PVPI), cardiac index (CI), systemic vascular resistance index (SVRI), serum albumin, time of first excision and grafting, and number of operations and daily fluid administration. Among these factors, we found that only burn size and ITBVI were significantly correlated with EVLWI variation and were further identified as the independent risk factors for EVLWI abnormality. ROC analysis showed that the limits for predicting a supranormal EVLWI during the fluid reabsorption stage were 65.5% TBSA for burn size and 845ml/m 2 for ITBVI. Patients with burn sizes or ITBVIs higher than the limit showed significantly longer mechanical ventilation time and substantially higher occurrences of acute respiratory distress syndrome (ARDS) and pneumonia within two weeks after burn., Conclusions: Burn size and ITBVI are the independent risk factors for EVLWI abnormality during the fluid reabsorption stage in severely burned adults. The limit values for predicting a supranormal EVLWI in those patients are 65.5% TBSA for burn size and 845ml/m 2 for ITBVI., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

Myocardial ischemia leads to copper efflux from the heart. The ischemic tissue with a low copper content fails to take up copper from the circulation even under the conditions of serum copper elevation. Cardiac copper repletion thus requires other available forms of this element than those currently known to bind to copper transport proteins. The copper complex of triethylenetetramine (TETA) is a metabolite of TETA, which has the potential to increase cardiac copper content in vivo. In the present study, we synthesized Cu(ii)-TETA, analyzed its crystal structure, and demonstrated the role of this compound in facilitating copper accumulation in primary cultures of neonatal rat cardiomyocytes. The Cu(ii)-TETA compound formed a square pyramidal chloride salt [Cu(TETA)Cl]Cl structure, which dissociates from chloride in aqueous solution to yield the four-coordinate dication Cu(ii)-TETA. Cu(ii)-TETA was accumulated as an intact compound in cardiomyocytes. Analysis from time-dependent copper accumulation in cardiomyocytes defined a different dynamic process in copper uptake between Cu(ii)-TETA and CuCl2 exposure. An additive copper accumulation in cardiomyocytes was found when the cells were exposed to both CuCl2 and Cu(ii)-TETA. Gene silencing of copper transport 1 (CTR1) did not affect cross-membrane transportation of Cu(ii)-TETA, but inhibited copper cellular accumulation from CuCl2. Furthermore, the uptake of Cu(ii)-TETA by cardiomyocytes was ATP-dependent. It is thus concluded that the formation of Cu(ii)-TETA facilitates copper accumulation in cardiomyocytes through an active CTR1-independent transportation process.

A strategy that employs the central-core regiochemistry to develop two isomeric perylene diimide (PDI)-based small molecular acceptors (SMAs), BPT-Se and BPT-Se1, is introduced, and the effect of the central-core regiochemistry on the optical, electronic, charge-transport, photovoltaic, and morphological properties of the molecules and their devices is investigated. The PDBT-T1:BPT-Se1-based device delivers a power conversion efficiency (PCE) of 9.54% with an excellent fill factor (FF) of 73.2%, while the BPT-Se-based device yields a PCE of 7.78%. The large improvement of PCE upon isomerization of BPT-Se should be ascribed to the concurrent enhancement of FF, short circuit current (  J SC ), and open circuit voltage ( V OC ) of the PDBT-T1:BPT-Se1 devices. The higher FF of the organic solar cells (OSCs) based on PDBT-T1:BPT-Se1 can be attributed to the higher charge dissociation and charge collection efficiency, less bimolecular combination, more balanced µ h / µ e , better molecular packing and a more favorable morphology. It is worth mentioning that the FF of 73.2% is the highest value for PDI-based SMAs OSCs to date. The result shows that regiochemistry of the central core in PDI-based SMAs greatly affects the physicochemical properties and photovoltaic performance. The success of the isomerization strategy offers exciting prospects for the molecular design of PDI-based SMAs., Competing Interests: The authors declare no conflict of interest.

Although parallel alignment of fibroblasts to the tension lines of scar has been evidenced in vivo, how scar contracture generates directional contraction remains largely unclear due to the lack of effective in vitro model. Fibroblast populated collagen lattice (FPCL), a widely used in vitro model, fails to mimic scar contracture since it produces concentric contraction with the random orientation of fibroblast. We hypothesized that a novel FPCL model with fibroblast alignment might produce directional contraction and then simulate scar contracture better. Here, we showed that although direct current electric fields (DCEFs) enabled fibroblasts aligned perpendicularly to the field vector, it also promoted electrotactic migration of fibroblast in FPCL. By contrast, biphasic pulse direct current electric fields (BPDCEFs), featured by reversal of the EF direction periodically, abolished the electrotactic migration, but induced fibroblast alignment in a pulse frequency dependent manner. Specifically, BPDCEF at a pulse frequency of 0.0002 Hz induced fibroblast alignment comparable to that induced by DCEF under the same field strength (300 mV/mm), leading to an enhanced contraction of FPCL along the direction of cell alignment. FPCL pretreated by BPDCEF showed an elliptical contraction whereas it was concentric in control FPCL. Further study revealed that F-actin redistributions acted as a key mechanism for the induction of fibroblasts alignment by BPDCEF. Cytochalasin D, an inhibitor of actin dynamics, abolished F-actins redistribution, and significantly suppressed the fibroblasts alignment and the directional contraction of FPCL. Importantly, BPDCEF significantly increased RhoA activity in fibroblasts, while this response was attenuated by C3 transferase pre-treatment, a potent inhibitor of RhoA, caused F-actin depolymerization and actin filament bundle randomly distributed. Taken together, our study suggests a crucial role for fibroblast orientation in scar contracture, and provides a novel FPCL model that may be feasible and effective for investigating scar contracture in vitro., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)

Two fullerene/non-fullerene hybrids were designed and synthesized for polymer solar cells as small molecule acceptors. Polymer solar cells based on J71:A2 achieved a power conversion efficiency of 4.52% with the open circuit voltage at nearly 1.0 V. The success of the hybrids may pave a new way for small molecule acceptors.

Isomers with small structural changes usually exhibit different properties. Rationally designing isomers of some high-performance SMAs can further enhance their function. In this work, an asymmetrical small molecule acceptor (SMA) MeIC1 isomerized from MeIC is reported. Compared with the symmetrical MeIC, the asymmetrical isomer showed almost the same absorption range but an elevated LUMO energy level and simultaneously enhanced π-π stacking and electron mobility by replacing the thieno[3,2- b ]thiophene unit with a larger sized dithieno[3,2- b :2',3'- d ]thiophene unit in the ladder-type core of MeIC. As a result, the MeIC1-based PSCs achieved a higher PCE up to 12.58% with a promoted V oc and J sc and an unchanged FF compared with those of MeIC-based PSCs when blended with PBDB-T. This work reveals that asymmetrical isomerization is effective for PCE promotion.

In this work, an effectual strategy of constructing polar small molecule acceptors (SMAs) to promote fill factor (FF) of nonfullerene polymer solar cells (PSCs) is first reported. Three asymmetrical SMAs of IDT6CN, IDT6CN-Th, and IDT6CN-M, which own large dipole moments, are designed and synthesized. The PSCs based on three polar SMAs exhibit apparently higher FFs compared with their symmetrical analogues. The asymmetrical design strategy accompanied with side chain and end group engineering makes IDT6CN-Th- and IDT6CN-M-based nonfullerene PSCs achieve high power conversion efficiency with FFs approaching 77%., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two different non-fullerene small-molecule acceptors, m-PIB and p-PIB, based on 9,9'-bifluorenylidene (BF) and perylene diimide (PDI) were designed and synthesized. Four β-substituted PDIs were linked to BF in different positions. Based on DFT analysis, derivative p-PIB exhibited reduced intramolecular twisting between the PDI moieties, more delocalized wave function, and sufficiently wider π-electron delocalization than that of m-PIB. The absorption ability of p-PIB was enhanced due to increased intermolecular interactions. By blending p-PIB with poly{4,8-bis[5-(2ethylhexyl)thiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-co-3-fluorothieno[3,4-b]-thiophene-2-carboxylate} (PTB7-Th), organic solar cells (OSCs) based on p-PIB obtained a maximum power conversion efficiency of 5.95 % without any treatments. Due to the improved and balanced hole and electron mobilities, the short-circuit current and fill factor of OSCs based on PTB7-Th and p-PIB were significantly increased. The AFM and TEM results revealed that the PTB7-Th:p-PIB film had favorable nanoscale phase separation and formed a bicontinuous interpenetrating network., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel small molecule acceptor MeIC with a methylated end-capping group is developed. Compared to unmethylated counterparts (ITCPTC), MeIC exhibits a higher lowest unoccupied molecular orbital (LUMO) level value, tighter molecular packing, better crystallites quality, and stronger absorption in the range of 520-740 nm. The MeIC-based polymer solar cells (PSCs) with J71 as donor, achieve high power conversion efficiency (PCE), up to 12.54% with a short-circuit current (J SC ) of 18.41 mA cm -2 , significantly higher than that of the device based on J71:ITCPTC (11.63% with a J SC of 17.52 mA cm -2 ). The higher J SC of the PSC based on J71:MeIC can be attributed to more balanced μ h /μ e , higher charge dissociation and charge collection efficiency, better molecular packing, and more proper phase separation features as indicated by grazing incident X-ray diffraction and resonant soft X-ray scattering results. It is worth mentioning that the as-cast PSCs based on MeIC also yield a high PCE of 11.26%, which is among the highest value for the as-cast nonfullerene PSCs so far. Such a small modification that leads to so significant an improvement of the photovoltaic performance is a quite exciting finding, shining a light on the molecular design of the nonfullerene acceptors., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two new non-fullerene acceptors, IDTC and IDTO, were designed and synthesized for the application in organic solar cells (OSCs). Compared with IDTC, the introduction of electron-donating alkoxy groups of IDTO leads to a higher LUMO level with a slightly blue-shifted absorption. Using the polymer PBDB-T as donor and the two small molecules as acceptors in the conventional device structure, the IDTC-based OSC exhibits a power conversion efficiency (PCE) of 9.35% with an open-circuit voltage (V OC ) of 0.917 V, a short-circuit current density (J SC ) of 16.56 mA cm -2 , and a fill factor (FF) of 61.61%. For the OSC based on IDTO, a higher PCE of 10.02% with a V OC of 0.943 V, a J SC of 16.25 mA cm -2 , and an FF of 65.41% are obtained. The more balanced μ e /μ h , evident aggregation, and phase separation contribute to the higher FF for the device based on IDTO. The increased J SC for the device based on PBDB-T:IDTC can be attributed to the red-shifted and stronger absorption of the PBDB-T:IDTC blend film. These results indicate fine-tuning the electronic energy and absorption of non-fullerene acceptors is feasible to improve the performance of OSCs.

Objective: To explore the effects of direct current electric fields on directional migration and arrangement of dermal fibroblasts in neonatal BALB/c mice and the related mechanisms., Methods: Twelve neonatal BALB/c mice were divided into 4 batches. The skin on the back of 3 neonatal mice in each batch was obtained to culture fibroblasts. Fibroblasts of the second passage were inoculated in 27 square cover slips with the concentration of 5 × 10(4) cells per mL. (1) Experiment 1. Six square cover slips inoculated with fibroblasts of the second passage were divided into electric field group (EF) and sham electric field group (SEF), with 3 cover slips in each group. The cover slips were put in live cell imaging workstation. The cells in group EF was treated with electric power with EF intensity of 200 mV/mm, while simulating process without actual power was given to SEF group (the same below) for 6 h. Cell proliferation rate was subsequently counted. (2) Experiment 2. Six cover slips were divided and underwent the same processes as in experiment 1. Cell movement locus within EF hour (EFH) 6, direction change of cell migration at EFH 0 (immediately), 1, 2, 3, 4, 5, and 6 which was denoted as cos(α), cell migration velocity within EFH 6, direction change of long axis of cell within EFH 6, and direction change of cell arrangement at EFH 0, 1, 2, 3, 4, 5, and 6 which was denoted as polarity value cos[2(θ-90)] were observed under live cell imaging workstation. After EFH 6, the morphological changes in microtubules and microfilaments were observed with immunofluorescent staining. (3) Experiment 3. Six cover slips were divided into cytochalasin D group (treated with 1 μmol/L cytochalasin D for 10 min) and colchicine group (treated with 5 μmol/L colchicine for 10 min), with 3 cover slips in each group. The morphological changes in microfilaments and microtubules were observed with the same method as in experiment 2. (4) Experiment 4. Nine cover slips were divided into control group (no reagent was added), cytochalasin D group and colchicine group (added with the same reagents as in experiment 3), with 3 cover slips in each group. Cells in the 3 groups were exposed to an EF of 200 mV/mm for 6 h. Cell movement locus within EFH 6, cell migration velocity within EFH 6, cell polarity values at EFH 0, 3, and 6, and morphological changes of cells at EFH 0 and 6 were observed. Data were processed with independent samples t-test, one-way analysis of variance, and LSD test., Results: (1) There was no statistically significant difference in cell proliferation rate in group EF and group SEF (t=-0.24, P﹥0.05). (2) Within EFH 6, cells in group EF migrated towards the anode of EF, while cells in group SEF moved randomly. At EFH 0, the values of cos(α) of cells in the 2 groups were both 0. The absolute value of cos(α) of cells in group EF (-0.57 ± 0.06) was significantly higher than that in group SEF (0.13 ± 0.09, t=6.68, P<0.01) at EFH 1, and it was still higher than that in group SEF from EFH 2 to 6 (with t values from 5.33 to 6.83, P values below 0.01). Within EFH 6, migration velocity of cells in group EF was (0.308 ± 0.019) μm/min, which was significantly higher than that in group SEF [(0.228 ± 0.021) μm/min, t=-2.76, P<0.01]. Within EFH 6, long axis of cells in group EF was perpendicular to the direction of EF, while arrangement of cells in group SEF was irregular. Cell polarity values in group EF were significantly higher than that in group SEF from EFH 2 to 6 (with t values from -7.52 to -0.90, P values below 0.01). At EFH 6, the morphology of microfilaments and microtubules of cells in EF group was similar to that in SEF group. (3) The fluorescent intensity of microfilaments of cells in cytochalasin D group became weakened, and the filamentary structure became fuzzy. The microtubules of cells in colchicine group became fuzzy with low fluorescent intensity. (4) Within EFH 6, cells in control group migrated towards the anode of EF, while cells in cytochalasin D group and colchicine group moved randomly. Within EFH 6, there was statistically significant difference in migration velocity of cells in the 3 groups (F=6.36, P<0.01). Migration velocity of cells in cytochalasin D group and colchicine group was significantly slower than that in control group (P<0.05 or P<0.01). At EFH 0, 3, and 6, cell polarity values in the 3 groups were close (with F values from 0.99 to 1.51, P values above 0.05). At EFH 0, cells in control group were spindle; cells in cytochalasin D group were polygonal or in irregular shapes; cells in colchicine group were serrated circle or oval. At EFH 6, no morphological change was observed in cells in control group; cells in cytochalasin D group were spindle with split ends on both ends; cells in colchicine group were serrated oval., Conclusions: The physiologic strength of exogenous direct current EF can induce directional migration and alignment of dermal fibroblasts in neonatal BALB/c mice. Microfilaments and microtubules are necessary skeleton structure for cell directional migration induced by EF, while they are not necessary for cell directional arrangement induced by EF.