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Combination of nonvolatile storage and in-memory computing promises to break through the "memory bottleneck" that computing device adopts von Neumann architecture with individual computing and memory unit. Thus, the advanced nonvolatile memory device with ultrafast operation speed is urgently required. Here, the optoelectronic hybrid phase-change memory based on the Ge2Sb2Te5 material is proposed, where the picosecond laser induced reversible phase-change is utilized to write and erase the information while the resistance difference is adopted to realize the accurate information readout. Due to the significant difference in resistance between crystalline and amorphous states, a partial crystallization strategy can be adopted to achieve ultrafast SET operation. Results indicate that SET operation speed of the Ge2Sb2Te5 film and device unit can be as fast as 52 and 130 ps, respectively, while the RESET speed reaches 13 ps. In parallel, the resistance ratio of RESET to SET state is still as high as two orders of magnitude. By using partial crystallization strategy, the phase-change induced by picosecond laser only occurs from amorphous to face-centered-cubic crystalline state with low crystallinity and the defective octahedral motif is observed in the Ge2Sb2Te5 film, which is beneficial to achieve the ultrafast operation speed. At the same time, the ordered clusters existed in the as-deposited and picosecond laser induced RESET films can accelerate the nucleation process of the Ge2Sb2Te5 film, which is one of the important reasons for achieving ultrafast SET speed. The optoelectronic hybrid phase-change memory with ultrafast operation speed may be one of the promising solutions for the in-memory computing. [ABSTRACT FROM AUTHOR]

The knowledge of intramolecular vibrational energy redistribution (IVR) and structural dynamics of rhenium photo-catalysts is essential for understanding the mechanism of the photo-catalytic process of CO2 reduction. In this study, the rhenium compound Re(dcbyp)(CO)3NCS (Re-NCS), which served as a model CO2 reduction catalyst, was investigated using two dimensional infrared (2D IR) spectroscopy. The vibrational relaxation dynamics and rotational dynamics of Re-NCS were measured by monitoring both the CO and NCS vibrational modes. The rotational dynamics measurement of the CO vibrational stretch shows a single exponential decay with a time constant of 140 ± 10 ps. In contrast, a bi-exponential decay is needed to describe the rotational dynamics of the NCS stretching mode with time constants of 1.5 ± 0.3 ps and 189 ± 15 ps. The 2D IR experiment indicated that the carbonyl CO vibrational modes in Re-NCS are strongly coupled. Furthermore, the intramolecular vibrational energy transfer between CO and NCS stretching modes was observed and analyzed based on an energy exchange model. The energy down flowing transfer from CN to CO stretching mode was determined using time constants of 50 ps. The relatively slow intramolecular vibrational energy transfer rate suggests that there is a weak coupling between CO and NCS ligands. Further theoretical calculation showed that the coupling strength between CO and CN is relatively weak and is about 5–6 times smaller than the coupling strength between the CO vibrational modes in Re-NCS. The distinct structural dynamics of the NCS ligand in Re-NCS presented in this study should provide a fundamental understanding of the role of an anionic ligand in rhenium photo-catalysts, which is believed to play an important role in the photo-catalytic reduction of CO2. [ABSTRACT FROM AUTHOR]

Enantioselective β‐Alkylation In article number 2303517, Yong Huang, Jiean Chen, and co‐workers, describe a novel SN2 reaction mode for NHC‐mediated homoenolate chemistry, enabling enantioselective β‐alkylation, allylation and propargylation of enals. By combining with a “transient acyl trap” strategy, a diverse collection of chiral oxindole derivatives could be accessed, offering an efficient synthetic entry to the pyrroloindoline motif frequently encountered in natural products. [ABSTRACT FROM AUTHOR]

The functionalization of the β-carbon of enals with electrophiles is a signature umpolung reactivity of N-heterocyclic carbene (NHC) derived homoenolates. However, only a limited number of electrophiles are shown to be compatible, with most of them being π-electrophiles. In this study, the successful enantioselective β-alkylation of homoenolates is reported using C sp3 electrophiles through an S N 2 strategy. The protocol shows a broad scope regarding alkyl electrophiles, delivering good yields, and excellent enantioselectivities (up to 99% ee). It enables the installation of drug-like structural motifs in either enals or alkylating agents, demonstrating its potential as a valuable tool for late-stage modification. Furthermore, a concise synthetic route is presented to chiral pyrroloindoline-type skeletons. Preliminary mechanistic studies support a direct S N 2 mechanism., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Integrins in the cell surface interact with functional motifs found in the extracellular matrix (ECM) that queue the cell for biological actions such as migration, adhesion, or growth. Multiple fibrous proteins such as collagen or fibronectin compose the ECM. The field of biomechanical engineering often deals with the design of biomaterials compatible with the ECM that will trigger cellular response (e.g., in tissue regeneration). However, there are a relative few number of known integrin binding motifs compared to all the possible peptide epitope sequences available. Computational tools could help identify novel motifs, but have been limited by the challenges in modeling the binding to integrin domains. We revisit a series of traditional and novel computational tools to assess their performance in identifying novel binding motifs for the I-domain of the α 2 β 1 integrin., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Liu and Perez.)

Background: Although previous studies have explored the moderating role of emotional regulation strategies in the relationship between empathy and depression, no studies have studied the moderating role of attentional control in the relationship between empathy and depression. To address this research gap, the present study investigated the moderating roles of rumination and attentional control in the relationship between empathy and depression., Methods: 423 participants filled out questionnaires anonymously, including Interpersonal Reactivity Index, Attention Control Scale, Self-rating Depression Scale, and Rumination Response Scale. PROCESS macro for SPSS was used for moderating effect analysis., Results: Rumination and attentional shift moderated the relationship between emotional empathy and depression. Specifically, the lower rumination or the higher attentional shift, the stronger the negative association between emotional empathy and depression. Attentional shift moderated the relationship between cognitive empathy and depression, and cognitive empathy was significantly associated with depression only among participants whose attentional shift is high., Conclusion: The study showed that rumination and attentional shift play important roles in the relationship between empathy and depression. The findings implicated that the positive role of good emotional regulation strategies and executive function for individuals in the relationship between empathy and depression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Zhao, Liu and Liu.)

Introduction: The increased social and economic burden caused by the novel COVID-19 outbreak is gradually becoming a worrisome issue for the health sector. The novel coronavirus invades the target cell by binding to ACE2, which is widely expressed in the ovaries, uterus, vagina and placenta. Significantly, the SARS-CoV-2 is said to interrupt female fertility through regulating ACE2. Thus, it is essential to investigate if the novel COVID-19 hampers female fertility, given that there is no systematic and comprehensive evidence on the association of COVID-19 with female fertility., Methods and Analysis: We will systematically search cohort studies, cross-sectional studies, case-control studies and self-controlled case series designs in the following databases: Web of Science, PubMed, EMBASE, Cochrane Library, Ovid, EBSCO, WHO COVID-19 Database, Chinese Biomedical Databases, China National Knowledge Internet, VIP and WanFang Database. Medical Subject Headings and free-text terms for "COVID-19" AND "female" AND "fertility" will be performed. Eligibility criteria are as follows: population (female patients aged 13-49 years); exposure (infection with SARS-CoV-2); comparison (population without SARS-CoV-2 infections or latent SARS-CoV-2 infections); and outcome (female fertility, such as ovarian reserve function, uterine receptivity, oviducts status and menstruation status). Article screening and data extraction will be undertaken independently by two reviewers, and discrepancies will be resolved through discussion. We will use the I 2 statistics to assess the heterogeneity and perform a meta-analysis when sufficiently homogeneous studies are provided. Otherwise, a narrative synthesis will be performed. We will explore the potential sources of heterogeneity using subgroup analyses and meta-regression., Ethics and Dissemination: Formal ethical approval is not required, and findings will be published in a peer-reviewed journal., Prospero Registration Number: CRD42020189856., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The knowledge of intramolecular vibrational energy redistribution (IVR) and structural dynamics of rhenium photo-catalysts is essential for understanding the mechanism of the photo-catalytic process of CO2 reduction. In this study, the rhenium compound Re(dcbyp)(CO)3NCS (Re-NCS), which served as a model CO2 reduction catalyst, was investigated using two dimensional infrared (2D IR) spectroscopy. The vibrational relaxation dynamics and rotational dynamics of Re-NCS were measured by monitoring both the CO and NCS vibrational modes. The rotational dynamics measurement of the CO vibrational stretch shows a single exponential decay with a time constant of 140 ± 10 ps. In contrast, a bi-exponential decay is needed to describe the rotational dynamics of the NCS stretching mode with time constants of 1.5 ± 0.3 ps and 189 ± 15 ps. The 2D IR experiment indicated that the carbonyl CO vibrational modes in Re-NCS are strongly coupled. Furthermore, the intramolecular vibrational energy transfer between CO and NCS stretching modes was observed and analyzed based on an energy exchange model. The energy down flowing transfer from CN to CO stretching mode was determined using time constants of 50 ps. The relatively slow intramolecular vibrational energy transfer rate suggests that there is a weak coupling between CO and NCS ligands. Further theoretical calculation showed that the coupling strength between CO and CN is relatively weak and is about 5-6 times smaller than the coupling strength between the CO vibrational modes in Re-NCS. The distinct structural dynamics of the NCS ligand in Re-NCS presented in this study should provide a fundamental understanding of the role of an anionic ligand in rhenium photo-catalysts, which is believed to play an important role in the photo-catalytic reduction of CO2.