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All‐polymer solar cells (all‐PSCs) present compelling advantages for commercial applications, including mechanical durability and optical and thermal stability. However, progress in developing high‐performance polymer donors has trailed behind the emergence of excellent polymer acceptors. In this study, we report a new electron‐deficient arene, fluorinated bithiophene imide (F‐BTI) and its polymer donor SA1, in which two fluorine atoms are introduced at the outer β‐positions in the thiophene rings of BTI to fine‐tune the energy levels and aggregation of the resulting polymers. SA1 exhibits a deep HOMO level of −5.51 eV, a wide bandgap of 1.81 eV and suitable miscibility with the polymer acceptor. Polymer chains incorporating F‐BTI result in a highly ordered π–π stacking and favorable phase‐separated morphology within the all‐polymer active layer. Thus, SA1 : PY‐IT‐based all‐PSCs exhibit an efficiency of 16.31 % with excellent stability, which is further enhanced to a record value of 19.33 % (certified: 19.17 %) by constructing ternary device. This work demonstrates that F‐BTI offers an effective route for developing new polymer materials with improved optoelectronic properties, and the emergence of F‐BTI will change the scenario in terms of developing polymer donor for high‐performance and stable all‐PSCs. [ABSTRACT FROM AUTHOR]

Dopant‐free hole transport layers (HTLs) play a crucial role in achieving high‐efficiency and stable perovskite solar cells (PSCs). However, only a limited number of these HTLs have demonstrated power conversion efficiencies (PCEs) surpassing 21%. Herein, the design and synthesis of two polymeric HTLs with a novel DA'D–A backbone are presented. The incorporation of two A units (benzothiazole and imide functionalized aromatics) in the polymer imparts a rigid backbone, high mobility, appropriate film morphology, excellent thermal stability, and a deeper highest occupied molecular orbital energy level, crucial for achieving a more suitable energy‐level alignment between HTL and perovskite layer. Notably, the champion PSC based on our HTLs exhibits a remarkable PCE of 22.02% with minimal hysteresis and excellent thermal stability, surpassing the performance of devices based on the benchmark polymeric HTL PTAA under identical conditions. These findings underscore the immense potential of our DA'D‐A backbone strategy in developing high‐performance dopant‐free polymer HTLs for enhancing the PCE of PSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: All‐polymer solar cells (all‐PSCs) have attracted considerable attention due to their inherent advantages over other types of organic solar cells, including superior optical and thermal stability, as well as exceptional mechanical durability. Recently, all‐PSCs have experienced remarkable advancements in device performance thanks to the invention of polymerized small‐molecule acceptors (PSMAs) since 2017. Among these PSMAs, PY‐IT has garnered immense interest from the scientific community due to its exceptional performance in all‐PSCs. In this review, we presented the design principles of PY‐IT and discussed the various strategies employed in device engineering for PY‐IT‐based all‐PSCs. These strategies include additive and interface engineering, layer‐by‐layer processing methods, meniscus‐assisted coating methods, and ternary strategy. Furthermore, this review highlighted several novel polymeric donor materials that are paired with PY‐IT to achieve efficient all‐PSCs. Lastly, we summarized the inspiring strategies for further advancing all‐PSCs based on PY‐IT. These strategies aim to enhance the overall performance and stability of all‐PSCs by exploring new materials, optimizing device architectures, and improving fabrication techniques. By leveraging these approaches, we anticipate significant progress in the development of all‐PSCs and their potential as a viable renewable energy source. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: All‐polymer solar cells (all‐PSCs) have attracted considerable attention due to their inherent advantages over other types of organic solar cells, including superior optical and thermal stability, as well as exceptional mechanical durability. Recently, all‐PSCs have experienced remarkable advancements in device performance thanks to the invention of polymerized small‐molecule acceptors (PSMAs) since 2017. Among these PSMAs, PY‐IT has garnered immense interest from the scientific community due to its exceptional performance in all‐PSCs. In this review, we presented the design principles of PY‐IT and discussed the various strategies employed in device engineering for PY‐IT‐based all‐PSCs. These strategies include additive and interface engineering, layer‐by‐layer processing methods, meniscus‐assisted coating methods, and ternary strategy. Furthermore, this review highlighted several novel polymeric donor materials that are paired with PY‐IT to achieve efficient all‐PSCs. Lastly, we summarized the inspiring strategies for further advancing all‐PSCs based on PY‐IT. These strategies aim to enhance the overall performance and stability of all‐PSCs by exploring new materials, optimizing device architectures, and improving fabrication techniques. By leveraging these approaches, we anticipate significant progress in the development of all‐PSCs and their potential as a viable renewable energy source. [ABSTRACT FROM AUTHOR]

Violent behavior recognition is an important direction of behavior recognition research. For traditional violent behavior recognition algorithms, there is too much background information when processing video information, which will cause greater interference in feature extraction, so the recognition accuracy is not high. Improved on the basis of effective recurrent convolutional network, a long-term recurrent convolutional network with attention mechanism is proposed. In the video preprocessing stage, a variety of attention mechanisms are introduced. In the feature extraction stage, the lightweight end-to-side neural network architecture GhostNet and convLSTM are selected to build a long-term recurrent convolutional network. The global average pooling and fully connected layer are used in the classification process. The combined approach realizes the classification of behaviours. The final results show that in the Hockey dataset, the algorithm in this paper has increased by 0.4% compared to LRCN, in the RWF-2000 dataset with more samples, it has increased by 10.5% compared to LRCN, and has increased by 1.75% compared to I3D, indicating that the algorithm in this paper can effectively suppress the background information. Interference, improve the performance of the algorithm.

Spontaneous intracerebral haemorrhage (ICH) is the main presentation in adults with moyamoya disease (MMD), an unusual clinical entity with a poor prognosis. However, optimal management in the acute stage of ICH in patients with MMD remains a challenge. Since minimally invasive surgery (MIS) plus local thrombolysis has emerged as a promising strategy for ICH, we aimed to describe our experience of performing this procedure in this special population in the acute phase, while focusing on its efficacy and safety. The medical data of patients with ICH treated with MIS and local thrombolysis between November 2013 and December 2017 were retrospectively reviewed at our institution. MMD was identified based on the angiographic images. The primary outcome was postoperative intracranial rebleeding. The secondary outcomes were 30-day mortality and 6-month outcome graded using the modified Rankin scale (mRS). Logistic regression was applied to explore independent risk factors for the above outcomes. A cohort of consecutive 337 ICH patients was analysed, of whom 14 (4.15%) were diagnosed with MMD. In total, 36 (11.46%) patients experienced postoperative intracranial rehaemorrhage, of which one patient had MMD. No significant difference was found between the patients with and without MMD regarding postoperative rebleeding (9.09% vs. 11.55%, p = 1.000). Additionally, the 30-day mortality of patients with MMD was 21.42% (3/14), which was not significantly different from that of non-MMD patients (10.83%; p = 0.201). Moreover, 53.8% of patients had poor outcomes at the 6-month follow-up among MMD patients, similar to 43.9% of patients without MMD (p = 0.573). The coexistence of MMD failed to show a significant association with postoperative intracranial rebleeding (p = 0.348), 30-day mortality (p = 0.211), or poor outcome at the 6-month follow-up (p = 0.450). Our findings suggest that coexistent MMD is not associated with an increased risk of postoperative rebleeding or poor outcome after local thrombolysis for ICH. [ABSTRACT FROM AUTHOR]

Polymerized small molecule acceptors have recently greatly facilitated the development of all‐polymer solar cells (All‐PSCs) with respect to the power conversion efficiencies (PCEs). However, high‐performance and low‐cost polymer donors for All‐PSCs are still lacking, limiting further large‐scale manufacturing of All‐PSCs. Herein, this work designs and synthesizes a new thiophene derivative, FETVT, featuring vinyl‐bridged fluorine and ester‐substituted monothiophene. Incorporation of FETVT into a polymer yields a high‐performance polythiophene derivative PFETVT‐T, which exhibits deep‐lying HOMO level, suitable solution pre‐aggregation ability, finely‐tuned polymer crystallinity, and appropriate thermodynamic miscibility with the polymer acceptor L15. As a result, binary based on PFETVT‐T achieves a record PCE of 11.81% with agood stability, representing a breakthrough for polythiophenes and their derivatives‐based All‐PSCs, which is also significantly higher than that (1.92%) of All‐PSCs based on its isomerized analog. Remarkably, PFETVT‐T achieves an impressive PCE exceeding 16% via the implementation of a ternary blend design. These findings offer a hopeful pathway toward attaining high‐performance, stable, and cost‐effective PSCs. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Omicron variant is undergoing continuous evolution and convergent mutation. These new subvariants are raising concerns that they may evade neutralizing monoclonal antibodies (mAbs). We investigated the serum neutralization efficacy of Evusheld (cilgavimab and tixagevimab) against SARS‐CoV‐2 Omicron BA.2, BA.2.75, BA.2.76, BA.5, BF.7, BQ.1.1, and XBB.1.5. A total of 90 serum samples from healthy individuals were collected in Shanghai. Anti‐RBD antibodies were measured and symptoms of infection with COVID‐19 were compared among those individuals. The neutralizing activity of serum against Omicron variants was analyzed by pseudovirus neutralization assays in 22 samples. Evusheld retained neutralizing activity against BA.2, BA.2.75, and BA.5, albeit with somewhat reduced titers. However, the neutralizing activity of Evusheld against BA.2.76, BF.7, BQ.1.1, and XBB.1.5 significantly decreased, with XBB.1.5 showing the greatest escape activity among the subvariants. We also observed that Evusheld recipients displayed elevated antibody levels in their serum, which efficiently neutralized the original variant, and exhibited different characteristics of infection than those who did not receive Evusheld. The mAb has partial neutralization activity against Omicron sublineages. However, the increasing doses of mAb and a larger size of population should be further investigated. [ABSTRACT FROM AUTHOR]