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Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism‐derived carbons as supports for noble‐metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR‐1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm‐associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g−1 and 6.85 A m−2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high‐quality bio‐Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions. [ABSTRACT FROM AUTHOR]

Background: Precise regulation of partial critical proteins in cancer cells, such as anti‐apoptotic proteins, is one of the crucial strategies for treating cancer and discovering related molecular mechanisms. Still, it is also challenging in actual research and practice. The widely used CRISPR/Cas9‐based gene editing technology and proteolysis‐targeting chimeras (PROTACs) have played an essential role in regulating gene expression and protein function in cells. However, the accuracy and controllability of their targeting remain necessary. Methods: Construction of UMUC‐3‐EGFP stable transgenic cell lines using the Sleeping Beauty system, Flow cytometry, quantitative real‐time PCR, western blot, fluorescence microplate reader and fluorescence inverted microscope analysis of EGFP intensity. Characterization of Survivin inhibition was done by using Annexin V‐FITC/PI apoptosis, calcein/PI/DAPI cell viability/cytotoxicity assay, cloning formation assay and scratch assay. The cell‐derived xenograft (CDX) model was constructed to assess the in vivo effects of reducing Survivin expression. Results: Herein, we established a synergistic control platform that coordinated photoactivatable split‐Cas9 targeted gene editing and light‐induced protein degradation, on which the Survivin gene in the nucleus was controllably edited by blue light irradiation (named paCas9‐Survivin) and simultaneously the Survivin protein in the cytoplasm was degraded precisely by a nanobody‐mediated target (named paProtacL‐Survivin). Meanwhile, in vitro experiments demonstrated that reducing Survivin expression could effectively promote apoptosis and decrease the proliferation and migration of bladder cancerous cells. Furthermore, the CDX model was constructed using UMUC‐3 cell lines, results from animal studies indicated that both the paCas9‐Survivin system and paProtacL‐Survivin significantly inhibited tumour growth, with higher inhibition rates when combined. Conclusions: In short, the coordinated regulatory strategies and combinable technology platforms offer clear advantages in controllability and targeting, as well as an excellent reference value and universal applicability in controlling the fate of cancer cells through multi‐level regulation of key intracellular factors. [ABSTRACT FROM AUTHOR]

Background: Noninvasive determination of Notch signaling is important for prognostic evaluation and therapeutic intervention in glioma. Purpose: To predict Notch signaling using multiparametric (mp) MRI radiomics and correlate with biological characteristics in gliomas. Study Type: Retrospective. Population: A total of 63 patients for model construction and 47 patients from two public databases for external testing. Field Strength/Sequence: A 1.5 T and 3.0 T, T1‐weighted imaging (T1WI), T2WI, T2 fluid attenuated inversion recovery (FLAIR), contrast‐enhanced (CE)‐T1WI. Assessment: Radiomic features were extracted from CE‐T1WI, T1WI, T2WI, and T2FLAIR and imaging signatures were selected using a least absolute shrinkage and selection operator. Diagnostic performance was compared between single modality and a combined mpMRI radiomics model. A radiomic–clinical nomogram was constructed incorporating the mpMRI radiomic signature and Karnofsky Performance score. The performance was validated in the test set. The radiomic signatures were correlated with immunohistochemistry (IHC) analysis of downstream Notch pathway components. Statistical Tests: Receiver operating characteristic curve, decision curve analysis (DCA), Pearson correlation, and Hosmer–Lemeshow test. A P value < 0.05 was considered statistically significant. Results: The radiomic signature derived from the combination of all sequences numerically showed highest area under the curve (AUC) in both training and external test sets (AUCs of 0.857 and 0.823). The radiomics nomogram that incorporated the mpMRI radiomic signature and KPS status resulted in AUCs of 0.891 and 0.859 in the training and test sets. The calibration curves showed good agreement between prediction and observation in both sets (P= 0.279 and 0.170, respectively). DCA confirmed the clinical usefulness of the nomogram. IHC identified Notch pathway inactivation and the expression levels of Hes1 correlated with higher combined radiomic scores (r = −0.711) in Notch1 mutant tumors. Data Conclusion: The mpMRI‐based radiomics nomogram may reflect the intratumor heterogeneity associated with downstream biofunction that predicts Notch signaling in a noninvasive manner. Evidence Level: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Synthesis of maleic anhydride (MA) and styrene (St) copolymers possessing ultra‐high molecular weight, strictly alternating regularity and high glass transition temperature simultaneously is still an issure with great challenge. Herein, the spontaneous alternating copolymerization of MA and St derivatives were investigated by using various Lewis acids. In the presence of alkyl aluminum or butyl magnesium, the MA−St alternating copolymers with ultra‐high molecular weight (Mn≤166.5×104) and high glass transition temperature (211 °C≤Tg≤216 °C) were produced and the microstructure of MA−St copolymers were analyzed by 1H and 13C NMR spectra. The copolymerizations of MA with St derivatives, including divinylbenzene, p‐butenyl styrene, p‐methoxystyrene, trans‐anethole, p‐fluorostyrene and p‐chlorostyrene, also were explored by using AlOctyl3 as an activator in toluene at 50 °C. [ABSTRACT FROM AUTHOR]

Disentangled ultrahigh molecular weight polyethylene (dis‐UHMWPE) has excellent processability but can be achieved under extreme conditions. Herein, we report ethylene polymerization with the binuclear half‐sandwich scandium complexes C1‐Sc2 and C2‐Sc2 to afford UHMWPE. C1‐Sc2 bearing a short linker shows higher activity and gives higher molecular weight PEs than C2‐Sc2 containing a flexible spacer and the mononuclear Sc1. Strikingly, all UHMWPEs isolated from C1‐Sc2 under broad temperature range (25–120 °C) and wide ethylene pressures (2–13 bar) feature very low degree of entanglement as proved by rheological test, DSC annealing study and SEM. These dis‐UHMWPEs are facilely mediated solid‐state‐process at 130 °C and their tensile strength and modulus reach up to 149.2 MPa and 1.5 GPa, respectively. DFT simulations reveal that the formation of dis‐UHMWPE is attributed to the binuclear synergic effect and the agostic interaction between the active center and the growing chain. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Coordination polymerization of renewable (E)‐4,8‐dimethyl‐1,3,7‐nonatriene (DMNT) has been performed using pyridyl‐methylene‐ fluorenyl scandium complex 1, half‐sandwich scandium complex 2, diiminophosphinato rare‐earth metal complexes 3a—3c and 4a—4b, bis(phosphino)carbazolide yttrium complex 5 and β‐diketiminato yttrium complex 6. Fluorenyl scandium complexes 1 and 2, activated by [Ph3C][B(C6F5)4] and AliBu3, are moderately active and show perfect 1,2‐regioselective (1,2 > 99%). Conversely, asymmetric diiminophophinato complexes 3a—3c promote the DMNT polymerization to produce high trans‐1,4 regulated products with the activity trend: Sc < Lu < Y. Complexes 4—6 are virtually inactive for the DMNT polymerization although they are highly active in isoprene polymerization. A diblock copolymer bearing 3,4‐polyisoprene block and trans‐1,4‐poly(DMNT) block is obtained using complex 3c in one‐pot reaction. Hydrogenation of trans‐1,4‐poly(DMNT) affords an elastomer with a Tg of –10°C. The epoxidation reaction of trans‐1,4‐poly(DMNT) with 3‐chloroperbenzoic acid transfers the pendant double bonds in the cis configuration into the epoxy groups. [ABSTRACT FROM AUTHOR]

Aim: To develop a scoring system for the prediction of a successful pregnancy. Methods: Data were collected prospectively from women diagnosed with pregnancy from January 1, 2015, to December 31, 2018. Pregnant days, hormone levels, and gestational sac diameters were recorded. Relationships among the pregnancy days, hormones, and gestational sac were analyzed by Spearman correlation analysis. A scoring system was established and stratified by the 5th, 50th, and 95th percentile of hormone levels and gestational sac diameters on different pregnancy days. Pregnancy outcomes were predicted by the scores using quadratic polynomial regression analyses. A portable desktop analyzer was developed and the performance was evaluated by receiver operating characteristic (ROC) curve. Results: In 273 successful pregnancy cases, the length of gestational days was significantly correlated to beta‐human chorionic gonadotropin (β‐hCG) (r = 0.74, p < 0.001) and E2 (r = 0.79, p < 0.001) levels, and the size of the gestational sac (r = 0.88, p < 0.001). Meanwhile, the size of gestational sac was positively correlated with β‐hCG (r = 0.93, p < 0.001) and E2 (r = 0.55, p < 0.001). For 273 delivery and 103 miscarriage cases included in this study, our scoring‐based prediction model rendered an area under the ROC curve (AUC) of 0.86 with the sensitivity of 78.31% and the specificity of 80.83%. Conclusions: We successfully developed a scoring‐based analyzer to evaluate the viability of embryos at different gestation stages and to predict the probability of a successful delivery, which would provide a reference for clinicians in postpregnancy management. [ABSTRACT FROM AUTHOR]

Syndioselective polymerization of unprotected polar styrenes has achieved great success via specially designed catalysts and the establishment of "self‐assisted" theory. In contrast, isospecific polymerization of polar styrenes has remained less explored. Herein, we present new racemic ansa‐bis(benz[e]indenyl) rare‐earth metal complexes and their high activity and perfect isoselectivity (mmmm>99 %) for the polymerization of unmasked polar styrenes without any activators. Moreover, the copolymerizations of para‐ and meta‐methoxystyrenes with styrene give gradient and random copolymers, respectively. The insertion rate of polar monomers could be readily tuned in the range of 0–100 mol % by changing their loading ratios. The resultant isotactic polar polystyrenes are quantitatively transformed into hydroxyl or methylsulfonyl polystyrenes with high Tgs. DFT calculations reveal the isospecific mechanism. [ABSTRACT FROM AUTHOR]

One challenge in the application of traditional metastable intermolecular composite (MIC) material is that MIC particles are not compatible with micro‐electro‐mechanical system. In the authors' work, a solution casting method was employed to prepare aluminium/polyvinylidene fluoride (Al/PVDF) MIC films. The morphological, structural and compositional information of the samples were characterised by scanning electron microscopy, X‐ray diffraction, energy dispersive spectroscopy and Fourier transform infrared spectroscopy. The energy‐release characteristics of Al/PVDF films were studied by thermogravimetric analysis and differential scanning calorimetry. The results show that heat output and mass loss increased as the thickness of MIC films reduced. The maximum heat release of the main exothermic peak was 1032 J/g. The kinetics process could be divided into three stages with apparent activation energy calculated by Kissinger and Starink methods of 128.86, 164.69 and 153.16 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Hydrogenolysis of alkyl‐substituted cyclopentadienyl (CpR) ligated thorium tribenzyl complexes [(CpR)Th(p‐CH2‐C6H4‐Me)3] (1–6) afforded the first examples of molecular thorium trihydrido complexes [(CpR)Th(μ‐H)3]n (CpR=C5H2(tBu)3 or C5H2(SiMe3)3, n=5; C5Me4SiMe3, n=6; C5Me5, n=7; C5Me4H, n=8; 7–10 and 12) and [(Cp#)12Th13H40] (Cp#=C5H4SiMe3; 13). The nuclearity of the metal hydride clusters depends on the steric profile of the cyclopentadienyl ligands. The hydrogenolysis intermediate, tetra‐nuclear octahydrido thorium dibenzylidene complex [(Cpttt)Th(μ‐H)2]4(μ‐p‐CH‐C6H4‐Me)2 (Cpttt=C5H2(tBu)3) (11) was also isolated. All of the complexes were characterized by NMR spectroscopy and single‐crystal X‐ray analysis. Hydride positions in [(CpMe4)Th(μ‐H)3]8 (CpMe4=C5Me4H) were further precisely confirmed by single‐crystal neutron diffraction. DFT calculations strengthen the experimental assignment of the hydride positions in the complexes 7 to 12. [ABSTRACT FROM AUTHOR]

Streoregular poly(vinyl alcohol) is hard to obtain because vinyl alcohol is unstable relative to its tautomer acetaldehyde, and the monomer precursor vinyl ester is poisonous to the coordination catalyst. Herein, the coordination polymerization of 2‐vinyl‐2,1‐borazanaphthalene (BN2VN) is reported by the linked or unlinked half‐sandwich ligands attached scandium precursors ((FluSiMe3)Sc(CH2SiMe3)2(THF) (THF = tetrahydrofuran, 1), (FluCH2CH2‐NHC‐R)Sc(CH2SiMe3)2(THF) (R = mesityl 2, iPr 3, Me 4), and (FluCH2Py)Sc(CH2SiMe3)2 (5) for the first time. Among these precursors, complex 5 converts 600 equivalents of BN2VN into polymer within 5 min to reach an activity as high as 8.99 × 105 g molSc−1 h−1. The resultant products show excellent syndiotacticity and melting temperatures above 300 °C, which can be transferred to syndiotactic poly(vinyl alcohol) with 90% rr triad content by postpolymerization oxidation. [ABSTRACT FROM AUTHOR]

The chain‐transfer reaction is rather important in coordination polymerization regarding catalytic efficiency, adjustment of molecular weight, and control of chain structure. To date, chain transfer to H2 and Al, Mg, and Zn alkyl compounds and β‐H elimination are the commonly encountered modes. Now a novel chain transfer to toluene is reported. By introducing fluorine atoms into the β‐diketimine ligands, an inert catalytic system for styrene (St) coordination polymerization was transferred into the highly active one. The activity increased with an increase in the number of fluorines in the ligands. Surprisingly, the molecular weights of resultant polystyrenes are very low (Mn=2000–6600 Da) despite of St loadings, corresponding up to 121 chains per active species. The mechanisms were investigated by DFT simulation, MALDI‐TOF MS, isotope tracing experiment and 2D NMR spectrum analyses, which revealed that the fluorine activated the polymerization and directed chain transfer to toluene. [ABSTRACT FROM AUTHOR]

We present the reactivity of four‐coordinate lutetium‐methanediide‐alkyl complexes 1 and 2 ((BODDIR)Lu2(CH2SiMe3)2(µ2‐CHSiMe3)(THF)2, R = iPr (1), R = Et (2)). The reaction of 2 with N,N‐diisopropylcarbodiimide (iPrN=C=NiPr) afforded a nucleophilic adduct 3 through insertion of three molecules of iPrN=C=NiPr into the Lu‐µ2‐CHSiMe3 or Lu‐CH2SiMe3 bonds. In subsequent three component reactions of 1 with N,N‐dicyclohexylcarbodiimide (CyN=C=NCy) and pyridine, different addition patterns led to completely different products. Addition of CyN=C=NCy first and then pyridine into complex 1 resulted in the formation of (BODDIiPr)Lu2(CH2SiMe3)[CyNC(NCy)CHC(NCy)NCy(SiMe3)][CyNC(C6H4N)NCy] (4) with insertion of two molecules of CyN=C=NCy into the Lu‐µ2‐CHSiMe3 bond. Reversing the addition sequence generated (BODDIiPr)Lu2[CyNC(NCy)C6H4N][CyNC(=CHSiMe3)NCy)][CyNC(C6H4N)NCy] (5) with insertion of only one molecule of CyN=C=NCy into the Lu‐µ2‐CHSiMe3 bond. The possible mechanistic pathway to generate 4 was elucidated by DFT calculations. [ABSTRACT FROM AUTHOR]

Coordination polymerization of renewable 3-methylenecyclopentene has been investigated for the first time using rare-earth metal-based precursors bearing various bulky ligands. All the prepared complexes catalyze controllable polymerization of 3-methylenecyclopentene into high molecular weight polymers, of which the NPN- and NSN-tridentate non-Cp ligated lutetium-based catalytic systems exhibited extremely high activities up to 11 520 kg/(molLu⋅h) in a dilute toluene solution (3.2 g/100 mL) at room temperature. The resultant polymers have pure 1,4-regioregularity (>99 %) and tailorable number average molecular weights (1-20×104) with narrow molecular weight distributions (polydispersity index (PDI)=1.45-1.79). DFT simulations were employed to study the polymerization mechanism and stereoregularity control. [ABSTRACT FROM AUTHOR]

ABSTRACT Here we report on the coordination polymerization of a vinyl-functionalized butadiene monomer, 3-methylenehepta-1,6-diene (MHD) with exclusive conjugated diene chemoselectivity, high 1,2-regioselectivity and moderate isotacticity (1,2-selectivity > 99%, mm triad = 93%). Random copolymers of MHD and other conjugated diene (isoprene or myrcene) are also synthesized. The pendent vinyl groups of MHD homo or copolymers could be quantitatively converted into various functional groups via thiol-ene click reaction. The resulting functionalized polybutadiene-based material display versatile thermal and surface properties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1031-1039 [ABSTRACT FROM AUTHOR]

Stereoselective coordination/insertion polymerization of the polar ortho-methoxystyrene has been achieved for the first time by using the cationic β-diketiminato rare-earth-metal species. High activity and excellent isoselectivity ( mmmm>99 %) were acheived. The unmasked Lewis-basic methoxy group does not poison the Lewis-acidic metal center, but instead activates the polymerization through σ-π chelation to the active species together with the vinyl group, thus lower the coordination and activation energies as compared with those of styrene derivatives lacking the methoxy group. [ABSTRACT FROM AUTHOR]

The first four-coordinate methanediide/alkyl lutetium complex (BODDI)Lu2(CH2SiMe3)2(μ2-CHSiMe3)(THF)2 (BODDI=ArNC(Me)CHCOCHC(Me)NAr, Ar=2,6- iPr2C6H3) ( 1) was synthesized by a thermolysis methodology through α-H abstraction from a Lu-CH2SiMe3 group. Complex 1 reacted with equimolar 2,6- iPrC6H3NH2 and Ph2CO to give the corresponding lutetium bridging imido and oxo complexes (BODDI)Lu2(CH2SiMe3)2(μ2- N-2,6- iPr2C6H3)(THF)2 ( 2) and (BODDI)Lu2(CH2SiMe3)2(μ2-O)(THF)2 ( 3). Treatment of 3 with Ph2CO (4 equiv) caused a rare insertion of Lu-μ2-O bond into the CO group to afford a diphenylmethyl diolate complex 4. Reaction of 1 with PhN=CO (2 equiv) led to the migration of SiMe3 to the amido nitrogen atom to give complex (BODDI)Lu2(CH2SiMe3)2-μ-{PhNC(O)CHC(O)NPh(SiMe3)-κ3N,O,O}(THF) ( 5). Reaction of 1 with tBuNC formed an unprecedented product (BODDI)Lu2(CH2SiMe3){μ2-[η2:η2- tBuNC(=CH2)SiMe2CHCN tBu-κ1N]}( tBuNC)2 ( 6) through a cascade reaction of NC bond insertion, sequential cyclometalative γ-(sp3)-H activation, CC bond formation, and rearrangement of the newly formed carbene intermediate. The possible mechanistic pathways between 1, PhNCO, and tBuNC were elucidated by DFT calculations. [ABSTRACT FROM AUTHOR]

A mild and efficient PhI(OAc)2-mediated trifluoromethylation reaction of N-arylacrylamides with TMSCF3 under metal-free conditions was developed. This method provides convenient access to a variety of useful CF3-containing oxindoles in moderate to good yields. [ABSTRACT FROM AUTHOR]

A simple approach to synthesize extremely high glass transition temperature (Tg > 300 °C) hydrocarbon polymers that introduces bridged cyclic backbone and bulky pendant group simultaneously is reported. This method uses highly 3,4‐regulated poly(phenyl‐1,3‐butadiene) as a prepolymer for cationic cyclization postmodification. The Tg of cyclized highly 3,4‐regulated (94.0%) poly(1‐phenyl‐1,3‐butadiene) (P(1‐PB)) can reach 304 °C. To further restrict the movement of bridged cyclic backbone by changing the position of the pendant substituent group, highly 3,4‐regulated (96.2%) poly(2‐phenyl‐1,3‐butadiene) (P(2‐PB)) is used as the prepolymer. The Tg of its cyclized product reaches 325 °C, and this value is the highest ever reported among all hydrocarbon polymers. The results indicate that the regularity of poly(phenyl‐1,3‐butadiene) and the pendant substituent group are crucial factors when synthesizing high‐temperature hydrocarbon polymers through this approach. A simple approach for the synthesis of extremely high glass transition temperature (Tg) hydrocarbon polymers via cationic cyclization of diene polymers is reported. The Tg of cyclized 3,4‐regulated (94.0%) poly(1‐phenyl‐1,3‐butadiene) reaches 304 °C, and that of cyclized 3,4‐regulated (96.2%) poly(2‐phenyl‐1,3‐butadiene) reaches 325 °C. The combination of high regularity of prepolymer and aromatic bulky pendant group is the key for this approach. [ABSTRACT FROM AUTHOR]

A mild and efficient PhI(OAc)2-mediated trifluoromethylation reaction of N-arylacrylamides with TMSCF3 under metal-free conditions was developed. This method provides convenient access to a variety of useful CF3-containing oxindoles in moderate to good yields. [ABSTRACT FROM AUTHOR]

Notable features of the title process are functional group tolerance, operational simplicity, and mild reaction conditions. [ABSTRACT FROM AUTHOR]