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It remains challenging to comprehensively understand the packing models of conjugated polymers, in which side chains play extremely critical roles. The side chains are typically flexible and non‐conductive and are widely used to improve the polymer solubility in organic solutions. Herein, a buffer chain model is proposed to describe link between conjugated backbone and side chains for understanding the relationship of crystallization competition of conductive conjugated backbones and non‐conductive side chains. A longer buffer chain is beneficial for alleviating such crystallization competition and further promoting the spontaneous packing of conjugated backbones, resulting in enhanced charge transport properties. Our results provide a novel concept for designing conjugated polymers towards ordered organization and enhanced electronic properties and highlight the importance of balancing the competitive interactions between different parts of conjugated polymers. [ABSTRACT FROM AUTHOR]

Our previous research has shown that melatonin (MLT) can reduce cryopreserved ovarian damage in mice. Yet, the molecular mechanism of MLT protection is still unclear. Some studies have shown that melatonin receptor 1 (MT1) is very important for animal reproductive system. To evaluate whether MLT exerts its protective effect on cryopreserved mice ovarian tissue via MT1, we added antagonist of MT1/MT2 (Luzindor) or antagonist of MT2 (4P‐PDOT) to the freezing solution, followed by cryopreservation and thawing of ovarian tissue. The levels of total superoxide dismutase (T‐SOD), catalase (CAT), nitric oxide (NO) and malondialdehyde (MDA) were detected. Besides, by using RT‐PCR and Western blotting, the expression of Bcl‐2, Bax and Nrf2/HO‐1 signalling pathway‐related proteins was detected. These findings demonstrated that compared with the melatonin group, the addition of Luzindor increased apoptosis, NO and MDA activities, decreased CAT and T‐SOD activities and inhibited Nrf2/HO‐1 signalling pathway. In conclusion, melatonin can play a protective role in cryopreserved ovarian tissue of mice through MT1 receptor. [ABSTRACT FROM AUTHOR]

Background: The high mortality rate of patients with acute myocardial infarction (AMI) remains the most pressing issue of modern cardiology. Over the past 10 years, there has been no significant reduction in mortality among patients with AMI. It is quite obvious that there is an urgent need to develop fundamentally new drugs for the treatment of AMI. Angiotensin 1–7 has some promise in this regard. Objective: The objective of this article is analysis of published data on the cardioprotective properties of angiotensin 1–7. Methods: PubMed, Scopus, Science Direct, and Google Scholar were used to search articles for this study. Results: Angiotensin 1–7 increases cardiac tolerance to ischemia/reperfusion and mitigates adverse remodeling of the heart. Angiotensin 1–7 can prevent not only ischemic but also reperfusion cardiac injury. The activation of the Mas receptor plays a key role in these effects of angiotensin 1–7. Angiotensin 1–7 alleviates Ca2+ overload of cardiomyocytes and reactive oxygen species production in ischemia/reperfusion (I/R) of the myocardium. It is possible that both effects are involved in angiotensin 1–7‐triggered cardiac tolerance to I/R. Furthermore, angiotensin 1–7 inhibits apoptosis of cardiomyocytes and stimulates autophagy of cells. There is also indirect evidence suggesting that angiotensin 1–7 inhibits ferroptosis in cardiomyocytes. Moreover, angiotensin 1–7 possesses anti‐inflammatory properties, possibly achieved through NF‐kB activity inhibition. Phosphoinositide 3‐kinase, Akt, and NO synthase are involved in the infarct‐reducing effect of angiotensin 1–7. However, the specific end‐effector of the cardioprotective impact of angiotensin 1–7 remains unknown. Conclusion: The molecular nature of the end‐effector of the infarct‐limiting effect of angiotensin 1–7 has not been elucidated. Perhaps, this end‐effector is the sarcolemmal KATP channel or the mitochondrial KATP channel. [ABSTRACT FROM AUTHOR]

Incorporating heteroatoms can effectively modulate the molecular optoelectronic properties. However, the fundamental understanding of BN doping effects in BN‐embedded polycyclic aromatic hydrocarbons (PAHs) is underexplored, lacking rational guidelines to modulate the electronic structures through BN units for advanced materials. Herein, a concise synthesis of novel B2N2‐perylenes with BN doped at the bay area is achieved to systematically explore the doping effect of BN position on the photophysical properties of PAHs. The shift of BN position in B2N2‐perylenes alters the π electron conjugation, aromaticity and molecular rigidness significantly, achieving substantially higher electron transition abilities than those with BN doped in the nodal plane. It is further clarified that BN position dominates the photophysical properties over BN orientation. The revealed guideline here may apply generally to novel BN‐PAHs, and aid the advancement of BN‐PAHs with highly‐emissive performance. [ABSTRACT FROM AUTHOR]

Background: The use of percutaneous coronary intervention (PCI) in patients with ST‐segment elevation myocardial infarction (STEMI) is associated with a mortality rate of 5%–7%. It is clear that there is an urgent need to develop new drugs that can effectively prevent cardiac reperfusion injury. ATP‐sensitive K+ (KATP) channel openers (KCOs) can be classified as such drugs. Results: KCOs prevent irreversible ischemia and reperfusion injury of the heart. KATP channel opening promotes inhibition of apoptosis, necroptosis, pyroptosis, and stimulation of autophagy. KCOs prevent the development of cardiac adverse remodeling and improve cardiac contractility in reperfusion. KCOs exhibit antiarrhythmic properties and prevent the appearance of the no‐reflow phenomenon in animals with coronary artery occlusion and reperfusion. Diabetes mellitus and a cholesterol‐enriched diet abolish the cardioprotective effect of KCOs. Nicorandil, a KCO, attenuates major adverse cardiovascular event and the no‐reflow phenomenon, reduces infarct size, and decreases the incidence of ventricular arrhythmias in patients with acute myocardial infarction. Conclusion: The cardioprotective effect of KCOs is mediated by the opening of mitochondrial KATP (mitoKATP) and sarcolemmal KATP (sarcKATP) channels, triggered free radicals' production, and kinase activation. [ABSTRACT FROM AUTHOR]

The backbone conformation plays a vital role in the solution aggregation behavior and photophysical and electrical properties of conjugated polymers. Previous studies indicated that the backbone conformation modification mainly relied on introducing various functional groups. However, regulating the molecular conformation through non‐covalent interactions is highly susceptible to external factors such as solvents and temperature. Herein, four isoindigo‐based polymers, IIDDP, IIDDP‐C0, IIDDP‐C1, and IIDDP‐C2, are developed with distinct chain conformation. Covalent bonds are employed to fix the dihedral angle of the donor fragment and then control the main‐chain conformation. Due to conformation‐locking, it was observed that the planarization of the main chain from the solution to the thin film could not be achieved in the desired polymers with twisted backbones. Further investigations revealed that the relationship between the backbone conformation and the solution‐state supramolecular structures play a critical role in controlling solid‐state microstructures and optoelectronic performance of conjugated polymers. [ABSTRACT FROM AUTHOR]

Molecular ordering of conjugated polymers both in solution‐state aggregates and in solid‐state microstructures is a determining factor of the charge transport properties in optoelectronic devices. However, the effect of backbone conformation in conjugated polymers on assembly structures is still unclear. Herein, to understand such backbone conformation effect, three novel chlorinated benzodifurandionge‐based oligo(p‐phenylene vinylene) (BDOPV) polymers are systematically developed. These BDOPV‐based polymers exhibit significantly twisted backbone conformation (near 90° interunit torsion angle) between conjugated units, which can prevent polymer chains from forming ordered assembly structures by increasing conformational energy penalty in closely packed chains. A higher rotational barrier of the torsion angle would further prevent polymer chains from assembling, finally resulting in nonaggregated chains in solution and highly disordered solid‐state packing structures. This work will deepen the understanding of the relationship between polymer backbone conformation and assembly structures, contributing to the exploration of the structure–property relationship of polymers. [ABSTRACT FROM AUTHOR]

Despite the remarkable synthetic accomplishments in creating diverse polycyclic aromatic hydrocarbons with B−N bonds (BN‐PAHs), their optoelectronic applications have been less exploited. Herein, we report the achievement of high‐mobility organic semiconductors based on existing BN‐PAHs through a "periphery engineering" strategy. Tetraphenyl‐ and diphenyl‐substituted BN‐anthracenes (TPBNA and DPBNA, respectively) are designed and synthesized. DPBNA exhibits the highest hole mobility of 1.3 cm2 V−1 s−1 in organic field‐effect transistors, significantly outperforming TPBNA and all the reported BN‐PAHs. Remarkably, this is the first BN‐PAH with mobility over 1 cm2 V−1 s−1, which is a benchmark value for practical applications as compared with amorphous silicon. Furthermore, high‐performance phototransistors based on DPBNA are also demonstrated, implying the high potential of BN‐PAHs for optoelectronic applications when the "periphery engineering" strategy is implemented. [ABSTRACT FROM AUTHOR]

Strong interchain interactions of conjugated polymers usually result in poor miscibility with molecular dopants, limiting the doping efficiency because of uncontrolled phase separation. We have developed a strategy to achieve efficient charge‐transport and high doping miscibility in n‐doped conjugated polymers. We solve the miscibility issue through disorder side‐chains containing dopants better. Systemic structural characterization reveals a farther side‐chain branching point will lead to higher disorders, which provides appropriate sites to accommodate extrinsic molecular dopants without harming original chain packings and charge‐transport channels. Therefore, better sustainability of solid‐state microstructure is obtained, yielding a stable conductivity even when overloading massive dopants. This work highlights the importance of realizing high host‐dopant miscibility in molecular doping of conjugated polymers. [ABSTRACT FROM AUTHOR]

Introducing BN units into polycyclic aromatic hydrocarbons expands the chemical space of conjugated materials with novel properties. However, it is challenging to achieve accurate synthesis of BN‐PAHs with specific BN positions and orientations. Here, three new parent B2N2‐perylenes with different BN orientations are synthesized with BN‐naphthalene as the building block, providing systematic insight into the effects of BN incorporation with different orientations on the structure, (anti)aromaticity, crystal packing and photophysical properties. The intermolecular dipole–dipole interaction shortens the π–π stacking distance. The crystal structure, (anti)aromaticity, and photophysical properties vary with the change of BN orientation. The revealed BN doping effects may provide a guideline for the synthesis of BN‐PAHs with specific stacking structures, and the synthetic strategy employed here can be extended toward the synthesis of larger BN‐embedded PAHs with adjustable BN patterns. [ABSTRACT FROM AUTHOR]

The role of solution aggregates on the charge transport process of conjugated polymers in electronic devices has gained increasing attention; however, the correlation of the charge carrier mobilities between the solution aggregates and the solid‐state films remains elusive. Herein, three polymers, FBDOPV‐2T, FBDOPV‐2F2T, and FBDOPV‐4F2T, are designed and synthesized with distinct aggregation behavior in solution. By combining contact‐free ultrafast terahertz (THz) spectroscopy and field‐effect transistor measurements, we track the charge carrier mobility of the aggregates of these polymers from the solution to the thin‐film state. Remarkably, the mobility of these three polymers is found to follow nearly the same trend (FBDOPV‐2T>FBDOPV‐2F2T≫FBDOPV‐4F2T) in both solutions and thin‐film states. The quantitative mobility correlation indicates that the charge transport properties of solution aggregates play a critical role in determining the thin‐film charge transport properties and final device performance. Our results highlight the importance of investigating and controlling solution aggregation structures towards efficient organic electronic devices. [ABSTRACT FROM AUTHOR]

Crystal structure of conjugated molecules and polymers is fundamentally critical to understand their multilevel microstructures, carrier transport, and diverse functions. However, to determine the crystal structure of conjugated polymers is a significant challenge, mainly due to the poor crystallinity, weak diffraction, and instability under high‐energy radiation. Here, we build the possible crystal structures of eight typical conjugated polymers, covering several widely used molecular segments in organic optoelectronics. We model the packing structures of these seed polymers based on synchrotron X‐ray diffractions and molecular simulations. These crystal structures provide a new platform to predict the packing structures of more related polymer systems, extending the molecular scope. Based on this polymer crystal structure database, the multiscale microstructures and charge transport properties of conjugated polymers can be predicted before experiments. This study sets up a polymer crystal structure database to eliminate the current trial‐and‐error approaches and accelerating the design of high‐performance conjugated polymers. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: By combination of two special structural units, a boron‐nitrogen‐fused polycyclic aromatic hydrocarbon and azulene with strong intramolecular dipoles, a novel BN aromatics, BN‐Az, has been designed and synthesized with unique characteristics. The structure, optical and electrochemical properties, as well as charge transport property of BN‐Az have been investigated. Notably, BN‐Az selectively responds to fluoride ions and protons with a significant color change, which could also be monitored by NMR spectra and single‐crystal X‐ray analysis, indicating its potential as an effective ion sensing material in stimuli‐responsive electronic devices. [ABSTRACT FROM AUTHOR]

Molecular doping plays an important role in the modification of carrier density of organic semiconductors thus enhancing their optoelectronic performance. However, efficient n‐doping remains challenging, especially owing to the lack of strongly reducing and air‐stable n‐dopants. Herein, an N‐heterocyclic carbene (NHC) precursor, DMImC, is developed as a thermally activated n‐dopant with the excellent stability in air. Its thermolysis in situ regenerates free NHC and subsequently dopes typical organic semiconductors. In sequentially doped FBDPPV films, DMImC does not disturb the π–π packing of the polymer and achieves good miscibility with the polymer. As a result, a high electrical conductivity of up to 8.4 S cm−1 is obtained. Additionally, the thermally activated doping and the excellent air stability permit DMImC to be noninteractively co‐processed with polymers in air. Our results reveal that DMImC can be served as an efficient n‐dopant suitable for various organic semiconductors. [ABSTRACT FROM AUTHOR]

The carbon encapsulation in a pomegranate manner effectively avoids inner‐active pulverization and perfectly provides electronic transmission network during lithiation and delithiation for high performance lithium‐ion batteries. Carbon‐encapsulated homogeneous nanocomposites derived from host–guest inclusion are first realized based on molecular‐level encapsulating of β‐cyclodextrin. On the basis of this unique arrangement, lamellar nanosheet anodes are further prepared using a freeze‐drying method for favoring Li‐ion migration. As results of this design, large reversible capacity, high rate capability, and excellent cycling stability are achieved simultaneously. This host–guest encapsulation at the molecular scale offers a new and effective way for the development of carbon encapsulation electrode materials. [ABSTRACT FROM AUTHOR]

High‐spin conjugated radicals have great potential in magnetic materials and organic spintronics. However, to obtain high‐spin conjugated radicals is still quite challenging due to their poor stability. We report the successful synthesis and isolation of a stable triplet conjugated diradical, 10,12‐diaryldiindeno[1,2‐b:2′,1′‐e]pyrazine (m‐DIP). With the m‐xylylene analogue skeleton containing electron‐deficient sp2‐nitrogen atoms, m‐DIP displays significant aromatic character within its pyrazine ring and its spin density mainly delocalizes on the meta‐pyrazine unit, making it a triplet ground state conjugated diradical. Our work provides an effective "spin density tuning" strategy for stable high‐spin conjugated radicals. [ABSTRACT FROM AUTHOR]

In the past few decades, conjugated polymers have aroused extensive interest in organic electronic applications. The electrical performance of conjugated polymers has a close relationship with their backbone conformation. The conformation of the polymer backbone strongly affects the πelectron delocalization along polymer chains, the energy band gap, interchain interactions, and further affects charge transport properties. To realize a rigid coplanar backbone that usually possesses efficient intrachain charge transport properties and enhanced π–π stackings, such conformation control becomes a useful strategy to achieve high‐performance (semi)conducting polymers. This minireview summarizes the most important polymer structures through conformation control at the molecular level, and then divides these rigid coplanar conjugated polymers into three categories: 1) noncovalent interactions locked conjugated polymers; 2) double‐bond linked conjugated polymers; 3) ladder conjugated polymers. The effect of the conformation control on physical nature, optoelectronic properties, and their device performance is also discussed, as well as the challenges of chemical synthesis and structural characterization. [ABSTRACT FROM AUTHOR]

Controlling the solution‐state aggregation of conjugated polymers for producing specific microstructures remains challenging. Herein, a practical approach is developed to finely tune the solid‐state microstructures through temperature‐controlled solution‐state aggregation and polymer crystallization. High temperature generates significant conformation fluctuation of conjugated backbones in solution, which facilitates the polymer crystallization from solvated aggregates to orderly packed structures. The polymer films deposited at high temperatures exhibit less structural disorders and higher electron mobilities (up to two orders of magnitude) in field‐effect transistors, compared to those deposited at low temperatures. This work provides an effective strategy to tune the solution‐state aggregation to reveal the relationship between solution‐state aggregation and solid‐state microstructures of conjugated polymers. [ABSTRACT FROM AUTHOR]

Realizing high polymer chain orientation and ordered thin‐film microstructures is beneficial for efficient charge transport of conjugated polymers. However, achieving a high alignment degree remains a challenge due to the sensitive nature of polymers to the processing conditions. By simply varying concentrations during a dip‐coating method, the component of polymer aggregates that adopt the planar backbones is enlarged and the ensuing assembly process is promoted. Herein, highly oriented polymer thin films of an isoindigo‐based conjugated polymer (PII‐2T) are prepared to enhance polymer orientation resulting in a drastic booming in carrier mobilities of organic field‐effect‐transistors (OFETs). The maximum mobility from aligned polymer films increases by up to 8.3 cm2 V−1 s−1, which is tenfold beyond the value evaluated from the unaligned direction or traditional spin‐coated samples. The enhanced orientation can also reduce the adverse effects of the contact resistance and facilitate charge transport in transistors. This work demonstrates that the highly aligned conjugated polymer films can be approached by the dip‐coating method while offers a latent cornerstone toward understanding the critical role of processing‐related parameters in determining morphology of solution‐coated thin films. [ABSTRACT FROM AUTHOR]

Low n‐doping efficiency and inferior stability restrict the thermoelectric performance of n‐type conjugated polymers, making their performance lag far behind of their p‐type counterparts. Reported here are two rigid coplanar poly(p‐phenylene vinylene) (PPV) derivatives, LPPV‐1 and LPPV‐2, which show nearly torsion‐free backbones. The fused electron‐deficient rigid structures endow the derivatives with less conformational disorder and low‐lying lowest unoccupied molecular orbital (LUMO) levels, down to −4.49 eV. After doping, two polymers exhibited high n‐doping efficiency and significantly improved air stability. LPPV‐1 exhibited a high conductivity of up to 1.1 S cm−1 and a power factor as high as 1.96 μW m−1 K−2. Importantly, the power factor of the doped LPPV‐1 thick film degraded only 2 % after 7 day exposure to air. This work demonstrates a new strategy for designing conjugated polymers, with planar backbones and low LUMO levels, towards high‐performance and potentially air‐stable n‐type polymer thermoelectrics. [ABSTRACT FROM AUTHOR]

Considerable efforts have been devoted to achieving stable acene derivatives for electronic applications; however, the instability is still a major issue for such derivatives. To achieve higher stability with minimum structural change, CC units in the acenes were replaced with isoelectronic BN units to produce a novel BN‐embedded tetrabenzopentacene (BNTBP). BNTBP, with a planar structure, is highly stable to air, moisture, light, and heat. Compared with its carbon analogue tetrabenzopentacene (TBP), BN embedment lowered the highest occupied molecular orbital (HOMO) energy level of BNTBP, changed the orbital distribution, and decreased the HOMO orbital coefficients at the central carbon atoms, which stabilize BNTBP molecules upon exposure to oxygen and sunlight. The single‐crystal microribbons of BNTBP exhibited good performance in field‐effect transistors (FETs). The high stability and good mobility of BNTBP indicates that BN incorporation is an effective approach to afford stable large‐sized acenes with desired properties. [ABSTRACT FROM AUTHOR]

The joint of the donor and acceptor moieties allows a facile and effective strategy to develop novel organic conjugated materials. However, few pieces of work report the understanding of the donor–acceptor interactions at the molecular level. Herein, we developed three small molecules containing one acceptor motif with different amounts of the donor unit. By combining theoretical calculations and energy level characterization, the lowest unoccupied molecular orbital (LUMO) levels of the three molecules were proven to be almost identical. The molecular packing modes were evaluated from crystal structure prediction. Owing to the donor–acceptor interactions, the packing mode can be tuned from a 1D slipped stacking to a 2D brick layer. The 2D molecular packing and charge transport channel endowed the materials a higher electron mobility of 3.29 cm2 V−1 s−1 in the single‐crystal field‐effect transistors after such modulation. [ABSTRACT FROM AUTHOR]

Polycyclic conjugated hydrocarbons containing antiaromatic four‐membered cyclobutadienoids (CDB) are of great fundamental and technical interest. However, their challenging synthesis has hampered the exploration and understanding of such systems. Reported herein is a modular and efficient synthesis of novel CBD‐containing acene analogues, dinaphthobenzo[1,2:4,5]dicyclobutadiene (DNBDCs), with orthogonally tunable electronic properties and molecular packing. The design also features strong antiaromaticity of the CBD units, as revealed by nucleus‐independent chemical shift and anisotropy of the induced current density calculations, as well as X‐ray crystallography. Tuning the size of silyl substituents resulted in the most favorable "brick‐layer" packing for triisobutylsilyl‐DNBDC and a charge mobility of up to 0.52 cm2 V−1 s−1 in field‐effect transistors. Introducing strong antiaromaticity: Reported here is a modular and efficient synthesis of a series of dinaphthobenzo[1,2:4,5]dicyclobutadienes with strong antiaromaticity, orthogonally tunable electronics and molecular packing, and high charge mobility. These features allow the application of the structures in organic electronics. CANAL=catalytic arene‐(oxa)norbornene annulation. [ABSTRACT FROM AUTHOR]

During a CHO cell culture production process, important parameters are generally well controlled by a feedback mechanism (PID loop) in order to ensure consistency in both productivity and product quality. These parameters typically include pH, dissolved oxygen (DO), and temperature. While most of these parameters are very well controlled within their specific deadband, stable DO control can be challenging. Oscillations in DO concentration are not uncommon and these fluctuations can be exacerbated with an efficient mass transfer aeration strategy. In this study, where an IgG2 producing cell line was used, we observed increased lactate accumulation accompanied by decreased titer production in lots with fluctuations in DO concentration (DOF) when compared with lots with stable DO control (DOS). We demonstrate that DOF had a greater impact on performance with respect to titer production and lactate accumulation than DO setpoint. Furthermore, we report that estimated specific oxygen uptake rates (qOURs) were lower in DOF lots when compared with DOS lots. We also report that purified mAb sourced from DOF lots yielded lower drug‐to‐antibody ratio (DAR) after the sulfhydryl‐targeted maleimide conjugation process when equivalent reducing agent was used. All mAb lots were within the analytical specifications for release, though a slight increase in measureable trisulfides were observed in DOF mAb lots. DO control aimed to minimize fluctuations around DO setpoint was essential for us to produce consistent DAR without adjusting the conjugation process. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1427–1437, 2018 [ABSTRACT FROM AUTHOR]

Abstract: A pair of interconvertible stereoisomers of imide‐fused corannulene derivatives was mixed with C60, which resulted in cocrystallization into a 1:1 segregated packing motif through concave–convex π–π interactions. Only one conformation was observed in the cocrystal owing to guest‐induced conformational switching. The 1D assemblies of the complex showed promising applications in organic electronics. [ABSTRACT FROM AUTHOR]

Abstract: Thiazoloisoindigo, a novel structural variation of isoindigo, is for the first time utilized to synthesize conjugated polymers. The polymer based on thiazoloisoindigo merges the advantages of the one based on thienoisoindigo and diazaisoindigo; it not only exhibits a greatly redshifted UV/Vis absorption to the near‐infrared region owing to its strong tendency to form quinoidal structures, similar to that based on thienoisoindigo, but also shows excellent ambipolar mobility (hole: 3.93, electron: 1.07 cm2 V−1 s−1) in organic field‐effect transistors (OFETs), superior to that based on diazaisoindigo, showing the strong electron‐withdrawing capability of thiazoloisoindigo. [ABSTRACT FROM AUTHOR]

Abstract: The construction of hollow structures has been used as an efficient strategy to improve electrochemical properties in lithium‐ion batteries (LIBs). In this paper, novel Co2V2O7 hollow cylinders have been fabricated via a unique etching process, in which H2O2 and CO(NH2)2 were selected as the etching agent and the release rate controlling agent, respectively. The formation process for the hollow structure and the etching mechanism have been investigated. Benefiting from the improved diffusion and transport of Li+, the Co2V2O7 hollow cylinder electrode demonstrates higher electrochemical performance as an anode material for LIBs than that of Co2V2O7 solid hexagonal prisms. Under a current density of 0.4 A g−1, the cycling capacity can be improved to 2.5 times greater than that of non‐etched hexagonal prisms. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of accumulated spinal axial biomechanical loading on mice lumbar disc and the feasibility of applying this method to establish a mice intervertebral disc degeneration model using a custom‐made hot plate cage. In previous studies, we observed that the motion pattern of mice was greatly similar to that of humans when they were standing and jumping on their lower limbs. There is little data to demonstrate whether or not accumulated spinal axial biomechanical loading could induce intervertebral disc degeneration in vivo. Methods: Twenty‐four 0‐week‐old mice were randomly divided into model 1‐month and 3‐month groups, and control 1‐month and 3‐month groups (n = 6 per group). The model groups was transferred into the custom‐made hot plate cage three times per day for modeling. The control group was kept in a regular cage. The intervertebral disc samples of the L3–L5 were harvested for histologic, molecular, and immunohistochemical studies after modeling for 1 and 3 months. Results: Accumulated spinal axial biomechanical loading affects the histologic, molecular, and immunohistochemical changes of mice L3–L5 intervertebral discs. Decreased height of disc and endplate, fissures of annulus fibrosus, and ossification of cartilage endplate were found in morphological studies. Immunohistochemical studies of the protein level showed a similar expression of type II collagen at 1 month, but a slightly decreased expression at 3 months, and an increased expression level of type X collagen and matrix metalloproteinase 13 (MMP13). Molecular studies showed that ColIIa1 and aggrecan mRNA expression levels were slightly increased at 1 month (P > 0.05), but then decreased slightly (P > 0.05). ColXa1, ADAMTS‐5, and MMP‐13 expression levels werer increased both at 1 and 3 months (P < 0.05). In addition, increased expression of Runx2 was observed. Conclusion: Accumulated spinal axial loading provided by a custom‐made hot plate accelerated mice lumbar disc and especially endplate degeneration. However, this method requires further development to establish a lumbar disc degeneration model. [ABSTRACT FROM AUTHOR]

Pseudosasa amabilis (McClure) (Poales: Gramineae) is a typical bamboo species naturally distributed in large area of south China and famous for its culm strength. Although bamboos were found to share the same development rule, the detailed internode morphology of bamboo culm was actually not fully expressed. We explored internode morphology of P. amabilis using 11 different physical parameters in different dimensions (1-4). As Taylor's power law ( TPL) is generally applicable to describe relationship between mean and variance of population density, here we used TPL to evaluate the differences between internodes, and further, the relationship between dimension and TPL. Results showed that length (L), hollow radius ( HR), hollow area ( HA), hollow cylinder volume ( HCV), total cylinder volume ( TCV), density (De), and weight (W) all presented positive skewed distribution in varying degrees. For the basic one-dimensional parameters, the 9th internode was the longest, the 7th the heaviest, while thickness (T) decreased with internodes. Diameter (D) decreased in general but with an inconspicuous local mode at the 5-6th internodes, potentially due to the rapid height growth. The longest (9th) internode was the 'turning point' for T-D and HR-D relationships. Scatter plot changing trends of W to the one-dimensional parameters after the heaviest (7th) internode were reversed, indicating a deceleration of growth speed. TPL was not holding well in one-dimensional parameters ( R2: 0.5413-0.8125), but keep increasing as the parameter's dimension increasing ( R2 > 0.92 for two-dimensional, R2 > 0.97 for three-dimensional, and R2 > 0.99 for four-dimensional parameters.), suggesting an emergence mechanism of TPL related to both the physical dimensions of morphological measures and the allometric growth of bamboo. From the physical fundamental level, all existences are the expression of energy distribution in different dimensions, implying a more general rule that energy distribution holds better TPL in higher dimension level. [ABSTRACT FROM AUTHOR]

p- or n-Dopants have played significant roles in the improvement of organic electronic devices through the controllable doping of organic semiconductors. However, there has been little study of air-stable n-dopants under ambient conditions with strong doping capability due to the low electron affinities of organic semiconductors. Herein, a 1,4-dihydropyridine-based derivative is designed and facilely synthesized as an efficient n-dopant. The doping process is systematically investigated by UV-vis-NIR spectroscopy in solution and ultraviolet photoelectron spectroscopy in the solid state. Excellent conductivities are obtained for a variety of doped n-type semiconductors via a simple solution process without further treatment, suggesting a broad class of 1,4-dihydropyridine derivatives could be used as n-dopants in future organic electronic devices. [ABSTRACT FROM AUTHOR]

The article introduces various topics covered in the issue including benefits of using sequence representations in medical field, the effectiveness of the retrieval-given queries, and major improvements in template extraction post temporality classifications.

A new electron-deficient unit with a fused 5-membered heterocyclic ring was developed by replacing a cyclopenta-1,3-diene from electron-rich donor indacenodithiophene (IDT) with a cyclohepta-4,6-diene-1,3-diimde unit. The imide bridge endows dithienylbenzenebisimide (BBI) with a fixed planar configuration and low energy levels for both the highest occupied molecular orbital (HOMO; −6.24 eV) and the lowest unoccupied molecular orbit (LUMO; −2.57 eV). Organic field-effect transistors (OFETs) based on BBI polymers exhibit electron mobility up to 0.34 cm2 V−1 s−1, which indicates that the BBI is a promising n-type building block for optoelectronics. [ABSTRACT FROM AUTHOR]

Organic electron-acceptor materials play an important role in organic electronics, especially in organic bulk heterojunction (BHJ) solar cells. Recently, many non-fullerene small molecular acceptors have been developed, in which aromatic fused-imides were proven to be a promising family of excellent electron acceptors. We developed a series of acenaphtho[1,2- k]fluoranthene-fused diimides, AFIs ( AFI1, AFI2 and AFI3), employing the Diels-Alder reaction as the crucial synthetic step. With electron-withdrawing diimide groups in their large conjugated backbone, AFIs display a LUMO level around −3.50 eV. These AFI compounds were used as the electron acceptors to fabricate organic photovoltaic devices. The power conversion efficiency (PCE) of up to 2.37 % was achieved with a high open-circuit voltage ( Voc) up to 0.96 V. [ABSTRACT FROM AUTHOR]

A porous structure is widely considered as an efficient way to improve lithium storage performance. In this paper, a novel porous Cu-doped CoSe2 product is prepared by annealing a ZIF-67 precursor and Se powder. This Cu-doped CoSe2 sample is composed of interconnected nanoparticles. The average particle size of the nanoparticles is around 80 nm. When evaluated as anode materials for lithium-ion batteries, this porous structure could effectively shorten the charge-transport path and accommodate volume expansion during charge/discharge cycling. Therefore, porous Cu-doped CoSe2 manifests both a superior rate capacity of about 747 mAh/g at 5 A/g and a stable cycling capacity of about 807 mAh/g for 200 cycles. [ABSTRACT FROM AUTHOR]

In order to realize high performance electrode for long-lived lithium ion batteries (LIBs), engineering microstructures of electrode materials, especially porous, hollow, and hierarchical nanostructures, holds great promise in preventing the capacity fading stem from mechanical stress and volume change. Here, this paper reports a facile strategy to fabricate porous Co3V2O8 nanosheets with large surface-to-volume ratio via a dehydration process using Co2V2O7·3.3H2O as precursor. Benefiting from layer-to-layer nanosheets with mesoporous structure created form electrochemical reconstruction, the Co3V2O8 electrode exhibits ever-increasing lithium storage capacity after a period of fading. When cycled at high current density of 1 A g−1, it demonstrates an unprecedented rate capacity with long cycle stability (2190 mAh g−1 after 750 cycles). This paper emphasizes the synergetic effect of in situ electrochemical reconstruction and interfacial lithium storage, which not only offers a new conception for understanding the self-recover capacity phenomenon, but also opens up possibilities for designing high-performance electrodes for LIBs. [ABSTRACT FROM AUTHOR]

Organic field-effect transistors (OFETs) have attracted much attention for the next-generation electronics. Despite of the rapid developments of OFETs, operational stability is a big challenge for their commercial applications. Moreover, the actual mechanism behind the degradation of electron transport is still poorly understood. Here, the electrical characteristics of poly{[ N, N-9-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-bithiophene)} (P(NDI2OD-T2)) thin-film transistors (TFTs) as a function of semiconductor/dielectric interfacial property and environment are systematically investigated, in particular, how the copresence of water, oxygen, and active hydrogen on the surface of dielectric leads to a sharp drop-off in threshold voltage. Evidence is found that an acid-base neutralization reaction occurring at the interface, as a combined effect of the chemical instability of dielectrics and the electrochemical instability of organic semiconductors, contributes to the significant electron trapping on the interface of P(NDI2OD-T2) TFTs. Two strategies, increasing the intrinsic electrochemical stability of semiconductor and decreasing the chemical reactivity of gate dielectric, are demonstrated to effectively suppress the reaction and thus improve the operational stability of n-type OFETs. The results provide an alternative degradation pathway to better understand the charge transport instability in n-type OFETs, which is advantageous to construct high-performance OFETs with long-term stability. [ABSTRACT FROM AUTHOR]

A novel electron-deficient building block, 5,5′-diazaisoindigo ( 5DNIID), was synthesized through a facile method in good yield. As a derivative of isoindigo, 5DNIID shows an ultra-low LUMO level of −3.92 eV after incorporation of two electron-deficient nitrogen atoms into the para-position of the amine groups in the isoindigo π skeleton. Modified polymerization conditions were applied to efficiently afford the donor-acceptor (D-A) conjugated polymer 5DNIID-2T, which exhibited a p-type charge transport property. [ABSTRACT FROM AUTHOR]