Mobility gradients yield rubbery surfaces on top of polymer glasses.

Many emerging materials, such as ultrastable glasses1,2 of interest for phone displays and OLED television screens, owe their properties to a gradient of enhanced mobility at the surface of glass-forming liquids. The discovery of this surface mobility enhancement3-5 has reshaped our understanding of the behaviour of glass formers and of how to fashion them into improved materials. In polymeric glasses, these interfacial modifications are complicated by the existence of a second length scale-the size of the polymer chain-as well as the length scale of the interfacial mobility gradient6-9. Here we present simulations, theory and time-resolved surface nano-creep experiments to reveal that this two-scale nature of glassy polymer surfaces drives the emergence of a transient rubbery, entangled-like surface behaviour even in polymers comprised of short, subentangled chains. We find that this effect emerges from superposed gradients in segmental dynamics and chain conformational statistics. The lifetime of this rubbery behaviour, which will have broad implications in constraining surface relaxations central to applications including tribology, adhesion, and surface healing of polymeric glasses, extends as the material is cooled. The surface layers suffer a general breakdown in time-temperature superposition (TTS), a fundamental tenet of polymer physics and rheology. This finding may require a reevaluation of strategies for the prediction of long-time properties in polymeric glasses with high interfacial areas. We expect that this interfacial transient elastomer effect and TTS breakdown should normally occur in macromolecular systems ranging from nanocomposites to thin films, where interfaces dominate material properties5,10.

GRP78 recognizes EV-F 3D protein and activates NF-κB to repress virus replication by interacting with CHUK/IKBKB.

Enteroviruses are the causative agents associated with several human and animal diseases, posing a significant threat to human and animal health. As one of the host immune defense strategies, innate immunity plays a crucial role in defending against invading pathogens, where the host utilizes a variety of mechanisms to inhibit or eliminate the pathogen. Here, we report a new strategy for the host to repress enterovirus replication by the 78 kDa glucose-regulated protein (GRP78), also known as heat shock protein family A member 5 (HSPA5). The GRP78 recognizes the EV-encoded RNA-dependent RNA polymerases (RdRPs) 3D protein and interacts with the nuclear factor kappa B kinase complex (CHUK) and subunit beta gene (IKBKB) to facilitate the phosphorylation and nuclear translocation of NF-κB, which induces the production of inflammatory factors and leads to a broad inhibition of enterovirus replication. These findings demonstrate a new role of GRP78 in regulating host innate immunity in response to viral infection and provide new insights into the mechanism underlying enterovirus replication and NF-κB activation.IMPORTANCEGRP78 is known as a molecular chaperone for protein folding and plays a critical role in maintaining protein folding and participating in cell proliferation, cell survival, apoptosis, and metabolism. However, the functions of GRP78 to participate in enterovirus genome replication and innate immune responses are rarely documented. In this study, we explored the functions of the EV-3D-interacting protein GRP78 and found that GRP78 inhibits enterovirus replication by activating NF-κB through binding to EV-F 3D and interacting with the NF-κB signaling molecules CHUK/IKBKB. This is the first report that GRP78 interacts with CHUK/IKBKB to activate the NF-κB signaling pathway, which leads to the expression of the proinflammatory cytokines and inhibition of enterovirus replication. These results demonstrate a unique mechanism of virus replication regulation by GRP78 and provide insights into the prevention and treatment of viral infections.

A Discrete, Boron-Containing Triangular Triradical.

A neutral boron-containing triangular triradical based on a triptycene derivative has been designed and synthesized. Its structure, bonding and physical property have been studied by EPR spectroscopy, SQUID magnetometry and single crystal X-ray diffraction, as well as theoretical calculations. The triradical has a series of isosceles triangle conformations in the solution due to the Jahn-Teller distortion, leading to the splitting of the two low-lying doublet states. This factor together with negligible spin-orbit coupling (SOC) of composing light atoms quenches the spin frustration. The work represents a rare example of a neutral through-space triangular triradical.

Molecular and Family Analyses of a Novel RHD1058G>C Allele in a Chinese RhD Population.

BACKGROUND: Rh(D) phenotype in a sample from a 19-year-old female patient showed weak positivity (1+). A follow-up sample was requested to further define the Rh(D) phenotype, her Rh(D) phenotype was tested by using another reagent, Rh(D) phenotype still showed weak reactivity (1+), RhCcEe phenotype was Ccee. METHODS: Seven samples from the family members of the proposita were received. The RhDCcEe phenotypes were typed by the microcolumn gel card and the unexpected antibodies were assayed by indirect anti-human globulin test (IAT). Genomic DNA was extracted from the blood sample and the novel RHD1058G>C allele was detected through an established sequence-specific primer PCR (PCR-SSP), RHD exons 1 - 10 were sequenced afterward by exon-specific amplification. The distribution of RHD1058G>C allele and RHD weak positive phenotype were investigated in the pedigrees. RESULTS: The unexpected antibodies all were negative in the family members. The novel RHD1058G>C allele was found in the proposita, her father, and grandfather. Five family members were detected serologically with the common Rh(D)-positive phenotypes either as homozygote of RHD/RHD or heterozygote of RHD/RHd. Two family members were detected as weak D phenotypes in accordance with the genotyping results by PCR-SSP, and both of them have a D1058Ce haplotype and a dce haplotype. One member, her father, was tested common Rh(D)-positive with D1058Ce haplotype and a Dce haplotype. CONCLUSIONS: These data allow us to describe the characteristics of the weak D phenotype with a novel c.RHD-1058G>C allele, which may be partial D and increase the risk of RHD alloantibody. The novel RHD1058G>C allele was inherited in three generations in a family rather than spontaneous mutation in an individual.

A chemical accident cause text mining method based on improved accident triangle.

BACKGROUND: With the rapid development of China's chemical industry, although researchers have developed many methods in the field of chemical safety, the situation of chemical safety in China is still not optimistic. How to prevent accidents has always been the focus of scholars' attention. METHODS: Based on the characteristics of chemical enterprises and the Heinrich accident triangle, this paper developed the organizational-level accident triangle, which divides accidents into group-level, unit-level, and workshop-level accidents. Based on 484 accident records of a large chemical enterprise in China, the Spearman correlation coefficient was used to analyze the rationality of accident classification and the occurrence rules of accidents at different levels. In addition, this paper used TF-IDF and K-means algorithms to extract keywords and perform text clustering analysis for accidents at different levels based on accident classification. The risk factors of each accident cluster were further analyzed, and improvement measures were proposed for the sample enterprises. RESULTS: The results show that reducing unit-level accidents can prevent group-level accidents. The accidents of the sample enterprises are mainly personal injury accidents, production accidents, environmental pollution accidents, and quality accidents. The leading causes of personal injury accidents are employees' unsafe behaviors, such as poor safety awareness, non-standard operation, illegal operation, untimely communication, etc. The leading causes of production accidents, environmental pollution accidents, and quality accidents include the unsafe state of materials, such as equipment damage, pipeline leakage, short-circuiting, excessive fluctuation of process parameters, etc. CONCLUSION: Compared with the traditional accident classification method, the accident triangle proposed in this paper based on the organizational level dramatically reduces the differences between accidents, helps enterprises quickly identify risk factors, and prevents accidents. This method can effectively prevent accidents and provide helpful guidance for the safety management of chemical enterprises.

Distribution, sources and ecological risks of PAHs and n-alkanes in water and sediments of typically polluted estuaries: Insights from the Xiaoqing River.

Seasonal water and sediment samples were collected from the Xiaoqing River estuary and the neighboring sea to study the spatial and temporal distributions, sources and ecological risks of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes. The results showed significant spatial and temporal differences in the concentrations of PAHs and n-alkanes under the influence of precipitation, temperature, and human activities. The concentrations of PAHs in water were lower in the wet season than in the dry season, and those in sediments were higher in the wet season than in the dry season. The concentrations of n-alkanes were higher in the rainy season than in the dry season for both water and sediments. The spatial distributions of PAHs and n-alkanes were estuarine > offshore. The concentration ranges of ∑PAHs in water and sediments were 230.66-599.86 ng/L and 84.51-5548.62 ng/g, respectively, in the wet season and 192.46-8649.55 ng/L and 23.39-1208.92 ng/g, respectively, in the dry season. The proportion of three-ring PAHs in water (57.03% and 78.27% in the wet and dry seasons, respectively) was high, followed by two-ring PAHs (27.31% and 13.59% in the wet and dry seasons, respectively). The proportion of four-ring PAHs was higher in sediments (24.79% and 32.20% in the wet and dry seasons, respectively). The ecological risk of PAHs assessed using the toxicity equivalent quotient and risk quotient was at moderate to moderately high risk levels. The high concentration of n-alkane fraction C16 (611.65-75594.58 ng/L) in the water is indicative of petroleum or other fossil fuel inputs. The main peaks of n-alkanes in river sediments were C27, C29 and C31, indicating higher inputs of plant sources. The sediments in the estuary showed dominance of both short-chain C16 and long-chain C25-C31, indicating a combined input of higher plants and petroleum. The diagnostic ratios of PAHs and n-alkanes indicated that their sources were mainly oil/coal/biomass combustion and petroleum spills attributed to frequent vehicular, vessel and mariculture activities. Given the potential ecological risks of PAHs and n-alkanes in water and sediments, future studies should focus on their bioaccumulation and biotoxicity.

Spin Frustration in Organic Radicals.

Spin frustration, which results from geometric frustration and a systematical inability to satisfy all antiferromagnetic (AF) interactions between unpaired spins simultaneously, is under the spotlight for its importance in physics and materials science. Spin frustration is treated as the structural basis of quantum spin liquids (QSLs). Featuring flexible chemical structures, organic radical species exhibit great potential in building spin-frustrated molecules and lattices. So far, the reported examples of spin-frustrated organic radical compounds include triradicals, tetrathiafulvalene (TTF) radicals and derivatives, [Pd(dmit)2 ] compounds (dmit=1,3-dithiol-2-thione-4,5-dithiolate), nitronyl nitroxides, fullerenes, polycyclic aromatic hydrocarbons (PAHs), and other heterocyclic compounds where the spin frustration is generated intra- or intermolecularly. In this Minireview, we provide a brief summary of the reported radical compounds that possess spin frustration. The related data, including magnetic exchange coupling parameters, spin models, frustration parameters, and crystal lattices, are summarized and discussed.

Isolable T-Shaped Planar Silyl Anion.

Silyl anions have garnered significant attention due to their synthetic abilities. However, previously reported silyl anions have been limited to either trigonal-pyramidal or trigonal-planar geometries, which confine them primarily as nucleophiles in substitution reactions. Herein, we report the isolation of the unprecedented T-shaped planar silyl anion salt 2 by employment of a geometrically constrained triamido pincer ligand. Theoretical calculations disclosed that the silicon centre in 2 possesses both a lone pair of electrons and an empty 3pz orbital. In addition to nucleophilic substitution reactions with Ph3PAuCl and W(CO)6, 2 readily undergoes oxidative additions with CO2 and 2,6-dimethylphenylisonitrile at room temperature. Furthermore, under mild conditions, compound 2 cleaves Csp2-H, Csp3-H, and H-H bonds in 1,2,4,5-tetrafluorobenzene, an intramolecular iPr group, and dihydrogen, representing the first examples of C-H and H-H activations mediated by a silyl anion, respectively. This work unveils new reactivity of silyl anions owing to the non-classical geometry and electronic structure.

Metal-Free Catalytic Formation of a Donor-Acceptor-Donor Molecule and Its Lewis Acid-Adduct Singlet Diradical with High-Efficient NIR-II Photothermal Conversion.

We have synthesized a quinone-incorporated bistriarylamine donor-acceptor-donor (D-A-D) semiconductor 1 by B(C6F5)3 (BCF) catalyzed C-H/C-H cross coupling via radical ion pair intermediates. Coordination of Lewis acids BCF and Al(ORF)3 (RF=C(CF3)3) to the semiconductor 1 afforded diradical zwitterions 2 and 3 by integer electron transfer. Upon binding to Lewis acids, the LUMO energy of 1 is significantly lowered and the band gap of the semiconductor is significantly narrowed from 1.93 eV (1) to 1.01 eV (2) and 1.06 eV (3). 2 and 3 are rare near-infrared (NIR) diradical dyes with broad absorption both centered around 1500 nm. By introducing a photo BCF generator, 2 can be generated by light-dependent control. Furthermore, the integer electron transfer process can also be reversibly regulated via the addition of CH3CN. In addition, the temperature of 2 sharply increased and reached as high as 110 °C in 10 s upon the irradiation of near-infrared-II (NIR-II) laser (1064 nm, 0.7 W cm-2), exhibiting a fast response to laser. It displays excellent photothermal stability with a photothermal (PT) conversion efficiency of 62.26 % and high-quality PT imaging.

The Dynamic Lewis Acid-Carbene Hybrid: Pushing the Electrophilicity of Carbenes to the Limit.

This work describes a Lewis-acid-coordination strategy to efficiently enhance the electrophilicity of a carbene beyond structural modification. A hybrid BCF-DAC is formed by the coordination of a Lewis acid, B(C6F5)3 (BCF), to an N,N'-diamidocarbene (DAC), possessing superior low LUMO energy that is indicated by theoretical calculation. This endows the hybridized carbene with a unique reactivity that speeds up the activation of the sp3-hybridized C-H bond of toluene and the [2+1] cycloaddition with C2H2. More strikingly, the hybrid readily undergoes [2+1] cycloaddition with C2H4 under ambient conditions, which is the first example of a stable carbene reacting with ethylene. The Lewis acid approach also features dynamic behavior and electrophilicity tunability.

A Dynamic Triradical: Synthesis, Crystal Structure, and Spin Frustration.

Polyradicals, i.e., multispin organic molecules, are playing important roles in radical-based material applications for their spin-spin interaction. A dynamic covalently bonded multispin molecule may endow materials with added function such as memory and switching. However, such a species has yet to be reported. We here report the synthesis, characterization, and crystal structure of a dynamic triradical species. It is generated by the self-assembly of two molecules through a Lewis acid coupled electron transfer. The crystalline species is spin-frustrated without Jahn-Teller distortion at low temperature, while it dissociates back to diamagnetic starting material in solution at high temperature. The reversible process is tracked by variable-temperature NMR, EPR, and UV-vis-NIR spectroscopy. Isolation, property study, and dynamic bonding investigation on such a species lay the foundation for the design of functional polyradicals with potential application as memory or switching devices.

Expression and immunogenicity of hepatitis E virus-like particles based on recombinant truncated ORF2 capsid protein.

Hepatitis E is an emerging zoonotic disease, posing a severe threat to public health in the world. Since there are no specific treatments available for HEV infection, it is crucial to develop vaccine to prevent this infection. In this study, the truncated ORF2 encoded protein of 439aa∼617aa (HEV3-179) from HEV CCJD-517 isolates was expressed as VLPs in E. coli with diameters of approximate 20 nm. HEV3-179 protein was immunized with mice, and the results showed that a higher titre of antibody was induced in NIH mice in comparison with that of KM mice (P < 0.01) and BALB/c mice (P < 0.01). The induced antibody titer is much higher in subcutaneous immunization mice than that in the mice inoculated via abdominal immunization (P < 0.05) and muscles immunization (P < 0.01). Mice immunized with 12 µg and 6 µg candidate vaccine induced higher level of antibody titer than that of 3 µg dosage group (P < 0.01, P < 0.05). Antibody change curve showed that HEV IgG antibody titer increased from 14 days post immunization (dpi) to 1:262144 and reached the peak level on 42 dpi before gradually retreated with the same level antibody titer with 1:131072 until 84 dpi. Mice inoculated with HEV3-179 produced higher titer of cytokines than the mock group, and the concentration of IL-1ß (P < 0.01) and IFN-γ (P < 0.01) further increased after stimulated by candidate vaccine. The result indicated that HEV3-179 possesses good immunogenicity, which could be used as a potential candidate for future HEV vaccine development.

The downstream PPARγ target LRRC1 participates in early stage adipocytic differentiation.

LRRC1 is a regulator of cellular polarity that is expressed at high levels in a range of tumor tissue types. Here, we conducted an analysis of the previously unexplored role of LRRC1 as a component of the adipogenic differentiation network. During the early stage (days 3-7) adipocytic differentiation of human mesenchymal stem cells (MSCs), LRRC1 was found to be upregulated at both the mRNA and protein levels. Moreover, the expression of LRRC1 was found to be controlled by PPARγ, which is a key transcriptional regulator of adipogenesis. Inhibiting LRRC1 expression reduced the adipogenic potential of hMSCs, with a concomitant reduction in the expression of three adipogenesis-associated proteins (SCD, LIPE, FASN). Together, these data offer new insight into the functional importance of LRRC1 both in general and in the context of adipocytic differentiation.

Flattened chains dominate the adsorption dynamics of loosely adsorbed chains on modified planar substrates.

Herein, the adsorption of polystyrene (PS) on phenyl-modified SiO2-Si substrates was investigated. Different from those for PS adsorption on a neat SiO2-Si substrate, the growth rate (vads) in the linear regime and hads/Rg (hads, thickness of flattened and loosely adsorbed layers on the substrate; Rg, radius of gyration) declined with increasing molecular weight (Mw) of PS and the phenyl content on the modified substrates, while the thickness of the flattened layer (hflat) and its coverage increased with increasing phenyl content. The results indicated that the adsorption of loose chains was controlled by the adsorption of flattened chains, as it only occurred in the empty contact sites remaining after the adsorption of flattened chains. Before approaching quasi-equilibrium (t < tcross), the number of flattened chain contact sites increased due to an enthalpically favorable process and, correspondingly, their spatial positions dynamically changed, which perturbed the adsorption of loose chains. When the adsorption of flattened chains reached quasi-equilibrium (t > tcross), the adsorption of loose chains was determined by the empty contact sites. The coverage of flattened chains and time to reach quasi-equilibrium were increased with more phenyl groups on the substrate, enhancing π-π interfacial interactions and resulting in a decreased adsorption rate and fewer loosely adsorbed chains. Mw-dependent vads and hads/Rg differed on phenyl-modified substrates compared to the neat SiO2-Si substrate owing to fewer empty contact sites for loose chains. The study findings improve our understanding of the mechanism responsible for the formation and structure of the adsorbed layer on solid surfaces.

The Role of Bacteria in the Formation and Migration of Oil-Particle Aggregates (OPAs) after Marine Oil Spills and the Associated Mechanism.

Oil spills interact with mineral particles to form oil-particle aggregates (OPAs), which promotes the oil's natural diffusion and biodegradation. We investigated the effect of bacteria on the formation and vertical migration of OPAs under different concentrations and types of particles and proposed and elucidated an oil-particle-bacteria coupling mechanism. The depth of particle penetration into oil droplets (13-17 µm) was more than twice that of the nonbacterial group. Oil that remained in the water column and deposited to the bottom decreased from 87% to 49% and increased from 14% to 15% at high/low concentration, respectively. Interestingly, the median droplet diameter showed a negative correlation (R2 = 0.83) and positive correlation (R2 = 0.60) at high/low concentration, respectively, with the relative penetration depth first proposed. We further demonstrated that bacteria increased the penetrating depth by a combination of reducing/increasing the interfacial tension, reducing the oil amount (C17-C38) in the OPAs, and increasing the particle width. These effects reduced the droplet size and ultimately changed the vertical migration of OPAs. Finally, we provided a simple assessment of the vertical distribution of OPAs in nearshore environments based on experimental data and suggested that the role of bacteria in increasing the depth of particles penetrating into the oil droplets should not be ignored. These findings will broaden the research perspective of marine oil spill migration.

Study on the prediction model of atherosclerotic cardiovascular disease in the rural Xinjiang population based on survival analysis.

PURPOSE: With the increase in aging and cardiovascular risk factors, the morbidity and mortality of atherosclerotic cardiovascular disease (ASCVD), represented by ischemic heart disease and stroke, continue to rise in China. For better prevention and intervention, relevant guidelines recommend using predictive models for early detection of ASCVD high-risk groups. Therefore, this study aims to establish a population ASCVD prediction model in rural areas of Xinjiang using survival analysis. METHODS: Baseline cohort data were collected from September to December 2016 and followed up till June 2022. A total of 7975 residents (4054 males and 3920 females) aged 30-74 years were included in the analysis. The data set was divided according to different genders, and the training and test sets ratio was 7:3 for different genders. A Cox regression, Lasso-Cox regression, and random survival forest (RSF) model were established in the training set. The model parameters were determined by cross-validation and parameter tuning and then verified in the training set. Traditional ASCVD prediction models (Framingham and China-PAR models) were constructed in the test set. Different models' discrimination and calibration degrees were compared to find the optimal prediction model for this population according to different genders and further analyze the risk factors of ASCVD. RESULTS: After 5.79 years of follow-up, 873 ASCVD events with a cumulative incidence of 10.19% were found (7.57% in men and 14.44% in women). By comparing the discrimination and calibration degrees of each model, the RSF showed the best prediction performance in males and females (male: Area Under Curve (AUC) 0.791 (95%CI 0.767,0.813), C statistic 0.780 (95%CI 0.730,0.829), Brier Score (BS):0.060, female: AUC 0.759 (95%CI 0.734,0.783) C statistic was 0.737 (95%CI 0.702,0.771), BS:0.110). Age, systolic blood pressure (SBP), apolipoprotein B (APOB), Visceral Adiposity Index (VAI), hip circumference (HC), and plasma arteriosclerosis index (AIP) are important predictors of ASCVD in the rural population of Xinjiang. CONCLUSION: The performance of the ASCVD prediction model based on the RSF algorithm is better than that based on Cox regression, Lasso-Cox, and the traditional ASCVD prediction model in the rural population of Xinjiang.

Intergenerational toxic effects of parental exposure to [Cn mim]NO3 (n = 2,4,6) on nervous and skeletal development in zebrafish offspring.

Ionic liquids (ILs) are thought to have negative effects on human health. Researchers have explored the effects of ILs on zebrafish development during the early stages, but the intergenerational toxicity of ILs on zebrafish development has rarely been reported. Herein, parental zebrafish were exposed to different concentrations (0, 12.5, 25, and 50 mg/L) of [Cn mim]NO3 (n = 2, 4, 6) for 1 week. Subsequently, the F1 offspring were cultured in clean water for 96 h. [Cn mim]NO3 (n = 2, 4, 6) exposure inhibited spermatogenesis and oogenesis in F0 adults, even causing obvious lacunae in the testis and atretic follicle oocytes in ovary. After parental exposure to [Cn mim]NO3 (n = 2, 4, 6), the body length and locomotor behavior were measured in F1 larvae at 96 hours post-fertilization (hpf). The results showed that the higher the concentration of [Cn mim]NO3 (n = 2, 4, 6), the shorter the body length and swimming distance, and the longer the immobility time. Besides, a longer alkyl chain length of [Cn mim]NO3 had a more negative effect on body length and locomotor behavior. RNA-seq analysis revealed several downregulated differentially expressed genes (DEGs)-grin1b, prss1, gria3a, and gria4a-enriched in neurodevelopment-related pathways, particularly the pathway for neuroactive ligand-receptor interaction. Moreover, several upregulated DEGs, namely col1a1a, col1a1b, and acta2, were mainly associated with skeletal development. Expression of DEGs was tested by RT-qPCR, and the outcomes were consistent with those obtained from RNA-Seq. We provide evidence showing the effects of parental exposure to ILs on the regulation of nervous and skeletal development in F1 offspring, demonstrating intergenerational effects.

Retention in nursing education and scholarship programs: Survival analysis of the Veterans Health Administration National Nursing Education Initiative Data.

AIMS: To investigate factors affecting non-completion by registered nurses (RNs) participating in degree programs supported by the scholarship program of the National Nursing Education Initiative of the United States Veterans Health Administration. Secondarily, to assess overall retention in the scholarship program over time. DESIGN: Retrospective longitudinal design using administrative data. METHODS: Defining retention time as the time elapsed from enrollment date to non-completion, we performed survival (retention) analysis (i.e.,Kaplan-Meier survival functions, log-rank tests and Cox regressions) to retrospectively analyzea national sample of RNs (N  = 15,908) enrolled in the scholarship program between the United States federal fiscal years 2000 and 2020. RESULTS: Nurses' mean age was 44 years (range: 19-71), and 86% were females. Six- and 12-month cumulative educational program retention rates were 92% and 84% respectively. The newest group of enrollees (2016-2020), younger nurses (<50 years), and nurses in traditional degree programtype were more likely to complete their academic programs than the earlier groups, older nurses and nurses in non-traditional type, respectively. Male nurses who aspired to advanced occupational levels upon completion were more likely to complete their academic programs compared to those who expected no change from their current level of practice. CONCLUSION: Multiple factors affected non-completion of academic degree programs by RNs enrolled in the scholarship program. More work is needed to examine these plus additional plausible factors and their correlates extensively. IMPACT: Our findings highlighted areas for quality improvement in employee scholarship programs for RNs. The findings are expected to inform tailoring of proactive helpful intervention towards individual needs and prioritization of limited resources to maximize graduation rate from academic programs for scholarship recipients. The study will have impact on nursing workforce policy makers interested in implementing employee scholarship programs, and on their scholarship recipients.

Recent advances in stable main group element radicals: preparation and characterization.

Radical species are significant in modern chemistry. Their unique chemical bonding and novel physicochemical properties play significant roles not only in fundamental chemistry, but also in materials science. Main group element radicals are usually transient due to their high reactivity. Highly stable radicals are often stabilized by π-delocalization, sterically demanding ligands, carbenes and weakly coordinating anions in recent years. This review presents the recent advances in the synthesis, characterization, reactivity and physical properties of isolable main group element radicals.

Lewis Acid-Mediated Radical Stabilization and Dynamic Covalent Bonding: Tunable, Reversible and Photocontrollable.

This work describes a strategy not only to isolate a dynamically stable radical with physical property tunability, but to efficiently regulate the radical dissociation with reversibility and photo controllability. The addition of Lewis acid B(C6 F5 )3 (BCF) into the solution of a radical σ-dimer (1-1) led to a stable radical (1⋅-2B), which has been characterized by EPR spectroscopy, UV/Vis spectroscopy and single crystal X-ray diffraction, in conjunction with theoretical calculation. The radical species is stabilized mainly by captodative effect, single electron transfer and steric effect. The absorption maximum of the radical can be tuned by using different Lewis acids. Dimer 1-1 can be achieved back by addition of a stronger base into the solution of 1⋅-2B, exhibiting a reversible process. By introducing a photo BCF generator, the dissociation of the dimer and the formation of the radical adduct become photocontrollable.