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Early/late heterobimetallic complexes are widely recognized as one of the most effective catalysts for activating coupling reactions. Herein, DFT calculations were used to investigate the specific mechanisms of terminal alkyne dimerization facilitated by two types of Zr/Co complexes: the bis (phosphinoamide) complex B and the mono (phosphinoamide) complex C. In addition, their reaction activities were compared with that of three ligand‐bridged Zr/Co complex A. The results show that the activated mechanisms of the three reactions are similar, all of them contain inner‐ and outer‐sphere mechanisms, and the inner one is the optimal process. Compared to A, the terminal alkyne dimerizations activated by B and C have the lower energy barriers and better selectivity for the E‐isomer; thus, the mono‐ and bis‐(phosphinoamide) Zr/Co complexes are expected to show better activity and selectivity than tris (phosphinoamide) complexes. The stereoselectivity of E‐, Z‐, and gem‐isomers is controlled by the reductive elimination process. The IRI analysis reveals that the selectivity for E‐ and Z‐isomers is influenced due to the notable repulsion and vdW interaction between the second alkyne and the MeNPMe2 ligand. Our work provides a theoretical basis for experimental applications and offers inspiration for the design of high selectivity heterobimetallic complexes. [ABSTRACT FROM AUTHOR]

Objectives: This systematic review and meta‐analysis aimed to determine the prevalence of loneliness and social isolation among informal carers of individuals with dementia and to identify potential influencing factors. Methods: We conducted a comprehensive search across 10 electronic databases, including PubMed, Cochrane, Embase, Web of Science, PsycINFO, CINAHL, Scopus, Chinese Biomedical, China National Knowledge Internet, and WANFANG. Our search strategy covered the inception of the databases up to September 16, 2023, with an updated search conducted on March 8, 2024. Prevalence estimates of loneliness and social isolation, presented with 95% confidence intervals, were synthesized through meta‐analysis. Subgroup analyses and meta‐regression were employed to explore potential moderating variables and heterogeneity. Results: The study encompassed 27 research papers involving 11,134 informal carers from 17 different countries. The pooled prevalence of loneliness among informal carers of individuals with dementia was 50.8% (95% CI: 41.8%–59.8%), while the pooled prevalence of social isolation was 37.1% (95% CI: 26.7%–47.6%). Subgroup analyses and meta‐regression indicated that various factors significantly influenced the prevalence of loneliness and social isolation. These factors included the caregiving setting, study design, the intensity of loneliness, geographical location (continent), data collection time, and the choice of assessment tools. Conclusions: This study underscores the substantial prevalence of loneliness and social isolation among informal carers of individuals with dementia. It suggests that policymakers and healthcare providers should prioritize the development of targeted interventions and support systems to alleviate loneliness and social isolation within this vulnerable population. Key points: Informal carers of people with dementia contend with unique circumstances that render them susceptible to both loneliness and social isolation.There is a significant prevalence of loneliness and social isolation in informal carers of individuals with dementia.Several significant moderators influence the prevalence of loneliness and social isolation among informal carers of individuals with dementia.Moderator analysis can guide targeted interventions and support systems for at‐risk informal carers of people with dementia to alleviate loneliness and social isolation. [ABSTRACT FROM AUTHOR]

Chalcogen bond catalysis, particularly cationic hypervalent chalcogen bond catalysis, is considered to be an effective strategy for organocatalysis. In this work, the cationic hypervalent chalcogen bond catalysis for the Povarov reaction between N‐benzylideneaniline and ethyl vinyl ether was investigated by density functional theory (DFT). The catalytic reaction involves the cycloaddition process and the proton transfer process, and the rate‐determining step is the cycloaddition process. Cationic hypervalent tellurium derivatives bearing CF3 and F groups exhibit superior catalytic activity. For the rate‐determining step, the Gibbs free energy barrier decreases as the positive electrostatic potential of the chalcogen bond catalysts increases. More importantly, the Gibbs free energy barrier has a strong linear correlation with the electrostatic energy of the chalcogen bond in the catalyst‐substrate complex. Furthermore, the catalytic reactions include the endo pathway and exo pathway. The C−H⋅⋅⋅π interaction between the substituent of the ethyl vinyl ether and the aryl ring of the N‐benzylideneaniline contributes to the endo‐selectivity of the reaction. This research contributes to a deeper understanding of chalcogen bond catalysis, providing insights for designing chalcogen bond catalysts with high performance. [ABSTRACT FROM AUTHOR]

The nature of π-hole spodium bonds in the HgLCl2⋯ZH3/CH2Y complexes (L = pyrrole 1, pyrazole 2, imidazole 3, pyridine 4, pyridazine 5, and pyrimidine 6; Z = N, P, As, and Sb; Y = O, S, Se, and Te) has been studied using theoretical calculations. The electrophilicity of the π-hole in the tri-coordinated HgII complexes varies with the type of N-heterocyclic ligand. The strength and nature of the π-hole spodium bond is closely related to the properties of the Lewis bases. In the case of HgLCl2⋯ZH3, the strength of the π-hole spodium bond weakens as the nucleophilicity of the base decreases, following the sequence HgLCl2⋯NH3 > HgLCl2⋯PH3 > HgLCl2⋯AsH3 > HgLCl2⋯SbH3. The Hg⋯Z spodium bonds change from a partially covalent interaction to a close-shelled noncovalent interaction. The nucleophilic ability of CH2Y decreases in the order CH2O > CH2S > CH2Se > CH2Te, while the strength of the π-hole spodium bond follows the order HgLCl2⋯OCH2 < HgLCl2⋯SCH2 < HgLCl2⋯SeCH2 < HgLCl2⋯TeCH2. The Hg⋯Y spodium bond undergoes a transition from a close-shelled noncovalent to a partially covalent interaction, resulting in an incremental increase in the degree of covalence. The Hg⋯Te spodium bond exhibits certain characteristics resembling those of a coordinate covalent bond. The inter-orbital interactions observed in the formation of the HgLCl2⋯YCH2 complexes appear to be significantly stronger compared to those observed in the HgLCl2⋯ZH3 complexation. [ABSTRACT FROM AUTHOR]

Accessible Summary: What is known on the subject?: Nurses often encounter traumatic events in their clinical practice.Trauma can have both negative effects, such as post‐traumatic stress disorder and positive effects, such as growth and positive emotions.Posttraumatic growth is beneficial for nurses, as it contributes to positive mental health outcomes and increases life satisfaction. What the paper adds to existing knowledge?: Our study confirms that nurses commonly experience posttraumatic growth after being exposed to traumatic events, and the level of growth is moderate.We have identified individual, work‐related, and social and organizational factors that may influence the occurrence of posttraumatic growth among nurses. What are the implications for practice?: Our findings provide valuable insights for interventions aimed at promoting posttraumatic growth among nurses. It is crucial to consider individual factors, work‐related factors, and social and organizational factors when designing these interventions. By addressing these factors, healthcare professionals can support nurses in coping with trauma and facilitate their posttraumatic growth. Introduction: While the negative effects of trauma on nurses have been well‐documented, it is equally important to focus on ways to promote posttraumatic growth (PTG) among nurses. Aim: This study aims to explore the levels and related factors of PTG among nurses. Method: A comprehensive search was conducted across nine databases up to 26 December 2022. The pooled mean score for PTG was calculated and presented with a 95% confidence interval. Subgroup and meta‐regression analyses were performed to identify potential moderators of PTG among nurses. Results: A total of 55 studies, involving 35,621 nurses from 11 countries and regions, were included in this review. The pooled scores of the PTG indicated that nurses experienced a moderate level of PTG (55.69, 95% CI: 50.67–60.72). Discussion: Nurses commonly experience PTG following exposure to traumatic events, with a moderate level of PTG. Our systematic review highlights the potential determinants of PTG among nurses, including individual, work‐related, and social and organizational factors. Implications for Practice: Targeting these factors in interventions can provide nurses with the necessary resources and support to effectively cope with stress and trauma, and potentially facilitate PTG. [ABSTRACT FROM AUTHOR]

Criegee intermediates (CIs), the key intermediates in the ozonolysis of olefins in atmosphere, have received much attention due to their high activity. The reaction mechanism of the most simple Criegee intermediate CH2OO with vinyl alcohol (VA) was investigated by using the HL//M06-2X/def2TZVP method. The temperature and pressure dependent rate constant and product branching ratio were calculated using the master equation method. For CH2OO + syn-VA, 1,4-insertion is the main reaction channel while for the CH2OO + anti-VA, cycloaddition and 1,2-insertion into the O–H bond are more favorable than the 1,4-insertion reaction. The 1,4-insertion or cycloaddition intermediates are stabilized collisionally at 300 K and 760 torr, and the dissociation products involving OH are formed at higher temperature and lower pressure. The rate constants of the CH2OO reaction with syn-VA and anti-VA both show negative temperature effects, and they are 2.95 × 10−11 and 2.07 × 10−13 cm3 molecule−1 s−1 at 300 K, respectively, and the former is agreement with the prediction in the literature. [ABSTRACT FROM AUTHOR]

Halogen bond donor catalysts have been widely used in organic reactions because they are environmentally friendly, inexpensive and recyclable. The [4+2] cycloaddition reaction is a key reaction in organic synthesis because of its ease of use, fast speed, and wide range of applications. In this work, halogen bond catalysis in the [4+2] cycloaddition reaction between 2-alkenylindoles was investigated based on DFT calculations. There are two modes of I⋯π halogen bond catalysis: either on the ethenyl of 2-alkenylindole (mode A) or on the five-membered ring of 2-alkenylindole (mode B). Both modes involve two steps: the formation of carbon–carbon bonds and the formation of six-membered rings. Gibbs free energy barriers were determined to investigate the stereoselectivity of the endo pathway and exo pathway. For mode A, the exo products were more easily generated when the substituent R = H, and the N–H⋯π interaction promoted high endo selectivity in the case of the substituent R = Ph. For mode B, an increasing proportion of endo products can be obtained in the order of catalyst I2, IBr and ICl. The π⋯π interaction of the substituent R = Ph promotes the [4+2] cycloaddition reaction, which is consistent with the experimental observation that R = Ph has a higher yield than R = H. The study of different catalytic modes and stereoselectivity would provide new ideas for the further study of the [4+2] cycloaddition reaction. [ABSTRACT FROM AUTHOR]

Recently, chalcogen bond catalysts with telluronium cations have garnered considerable attention in organic reactions. In this work, chalcogen bond catalysis on the bromination reaction of anisole with N‐bromosuccinimide (NBS) with the telluronium cationic catalysts has been explored with density functional theory (DFT). The catalytic reaction is divided into two stages: the bromine transfer step and the proton transfer step. Based on the computational results, one can find the rate‐determining step is the bromine transfer step. Moreover, the present study elucidates that a stronger chalcogen bond between catalysts and NBS will give better catalytic performance. Additionally, this work also clarified the importance of the electrostatic and polarization effects in the chalcogen bond between the oxygen atom of NBS and the Te atom of the catalyst in this bromination reaction. The electrostatic and polarization effects are significantly influenced by the electron‐withdrawing ability of the substitution groups on the catalysts. Moreover, the structure‐property relationship between the strength of chalcogen bond, electrostatic effect, polarization effect and catalytic performance are established for the design of more efficient chalcogen bond catalysts. [ABSTRACT FROM AUTHOR]

This qualitative systematic review aims to comprehensively understand the experiences and perspectives of nurses infected with COVID‐19, addressing a significant gap in the current literature. Following the JBI meta‐synthesis approach, a rigorous search was conducted across nine electronic databases and references until January 16, 2023. Seventeen eligible studies underwent quality assessment using the JBI critical checklist. Data were synthesized using standardized tools, and the ConQual tool evaluated confidence in the findings. Seven key findings emerged, providing valuable insights into emotional experiences, adaptation to COVID‐19 challenges, influence of support systems, coping strategies, posttraumatic growth perceptions, and effects on professional identity and career advancement. The findings highlight emotional toll, adaptive strategies, and professional implications for nurses. Moreover, they emphasize the importance of support systems, coping mechanisms, and posttraumatic growth in promoting nurses' well‐being and resilience. These insights have practical implications for targeted interventions and support mechanisms to enhance infected nurses' well‐being and improve healthcare outcomes. [ABSTRACT FROM AUTHOR]

Compressed sensing (CS) is a popular data compression theory for many computer vision tasks, but the high reconstruction complexity for images prevents it from being used in many real-world applications. Existing end-to-end learning methods achieved real time sensing but lack theory guarantee for robust reconstruction results. This paper proposes a neural network called RootsNet, which integrates the CS mechanism into the network to prevent error propagation. So, RootsNet knows what will happen if some modules in the network go wrong. It also implements real-time and successfully reconstructed extremely low measurement rates that are impossible for traditional optimization-theory-based methods. For qualitative validation, RootsNet is implemented in two real-world measurement applications, i.e., a near-field microwave imaging system and a pipeline inspection system, where RootsNet easily saves 60% more measurement time and 95% more data compared with the state-of-the-art optimization-theory-based reconstruction methods. Without losing generality, comprehensive experiments are performed on general datasets, including evaluating the key components in RootsNet, the reconstruction uncertainty, quality, and efficiency. RootsNet has the best uncertainty performance and efficiency, and achieves the best reconstruction quality under super low-measurement rates. [ABSTRACT FROM AUTHOR]

Except for the well-known σ-hole regium bonds formed by metal nanoparticles and M(I) (M = Cu, Ag, and Au) derivatives, the existence of π-hole regions located above and below the Au atom in gold(III) derivatives suggests that gold(III) also functions as an efficient electrophilic site. In this study, a comprehensive analysis was conducted on the electrophilicity of trichloro-(p-toluonitrilo-N)-gold(III) derivatives AuL3(NCC6H4X) (L = Cl, Br, CN; X = NH2, CH3, CF3, NC, and CN) and the nature of π-hole regium bonds in the AuL3(NCC6H4X)⋯LB (LB = NH3, N(NH3)3, CH2O, C2H2, C2H4, C6H6) and (AuCl3(NCC6H4Y))n (Y = Cl, CN, NC, NO2; n = 2, 3)) complexes. The characteristics of the π-hole regium bonds were studied with respect to the influence of ligands and substituents, the strength of intermolecular interactions between Au(III) derivatives and Lewis bases, and those in the polymers. In the case of the AuL3(NCC6H4X)⋯NH3 complexes, the strength of the regium bonds increases gradually in the order of L = Cl < Br < CN and X = NH2 < CH3 < CF3 ≈ NC < CN. The ligands (L) attached to the Au atom exert a significant effect on the strength of the π-hole regium bonds in comparison to the substituents (X) on the benzene ring. The regium bonds are primarily dominated by electrostatic interaction, accompanied by moderate contribution from polarization. Linear relationships were identified between the electrostatic energies and the local most positive potentials over the Au atom, as well as between the polarization energies and the amount of charge transfer. Most of the π-hole regium bonds in the AuL3(NCC6H4X)⋯LB complexes exhibit the characters of closed shell noncovalent interactions. In the polymers (AuCl3(NCC6H4Y))n, weak face-to-face π–π stacking interactions are also present, in addition to regium bonds. The trimers displayed a slightly negative cooperativity in comparison to the dimers. [ABSTRACT FROM AUTHOR]

There have been remarkable advances in the syntheses and applications of groups 13 and 14 homonuclear ethene analogues. However, successes are largely limited to aryl‐ and/or silyl‐substituted species. Analogues bearing two or more heteroatoms are still scarce. In this work, the block‐localized wavefunction (BLW) method at the density functional theory (DFT) level was employed to study dialumene and disilene bearing two amino substituents whose optimal geometries exhibit significantly stretched central M=M (M=Al or Si) double bonds compared with aryl‐ and/or silyl‐substituted species. Computational analyses showed that the repulsion between the lone electron pairs of amino substituents and M=M π bond plays a critical role in the elongation of the M=M bonds. Evidently, replacing the substituent groups −NH2 with −BH2 can enhance the planarity and shorten the central double bonds due to the absence of lone pair electrons in BH2. [ABSTRACT FROM AUTHOR]

Halogen bond catalysis, especially iodine derivatives catalysis, has attracted increasing attention in recent years owing to the advantages of relatively cheap, stable, green, easy to handle, and favorable catalytic activity. To obtain insights into the catalytic mechanism and activity of halogen bond donor catalysts, iodine(I)-based and iodine(III)-based halogen bond catalysis on the Friedel–Crafts reaction were investigated in this study. The entire reaction contains several key steps: carbon–carbon bond coupling, proton transfer, hydroxyl departure, indole addition, and deprotonation process. According to the energetic span model, iodine(III)-based donor catalysts exhibit higher catalytic activity than iodine(I)-based catalysts and double cationic catalysts are more potent than single cationic ones. For halogen bond catalysis, the Gibbs energy barriers have linear relation to the electron density at the halogen bond critical points. Furthermore, the Gibbs energy barriers are also linearly related to the integral charge values of the increased region of electron density outside the oxygen atom of reactants. Therefore, the stronger halogen bond results in lower Gibbs energy barrier, and the stronger polarization further benefits the halogen bond catalysis. [ABSTRACT FROM AUTHOR]

Recently, the green and high efficient of chalcogen bond (ChB) catalysis has been aroused great interest. In this work, the ChB catalysis has been applied to the intramolecular Rauhut‐Currier (RC) reaction of bis(enones). The mechanism was divided into four processes: the promoter addition process, the carbon‐carbon bond coupling process, the hydrogen transfer process, and the promoter elimination process. This study shows that the ChB catalyst could act on the promoter and reactant in the RC reaction, respectively. And the path 2 of ChB catalyst direct acting on the reactant is considered to be a relatively favorable channel of the reaction due to a lower energy barrier. In addition, all six catalysts could achieve good catalytic effect. Analysis of the properties shows that the formation of chalcogen bond mainly promotes the charge transfer of LP(O)−BD*(C−Se) in the carbon‐carbon bond formation (key step), so that the charge of C(4) atom become more positive, thereby accelerating the reaction. [ABSTRACT FROM AUTHOR]