bluuebunny/crossref_metadata_2025_split huggingface dataset:
Convergent Assembly of the Tricyclic Labdane Core Enables Synthesis of Diverse Forskolin‐like Molecules
Authors: Szczepanik Paweł M. , Mikhaylov Andrey A. , Hylse Ondřej , Kučera Roman , Daďová Petra , Nečas Marek , Kubala Lukáš , Paruch Kamil , Švenda Jakub 
Published: November 2022

AbstractWe report a new synthetic strategy for the flexible preparation of forskolin‐like molecules. The approach is different from the previously published works and employs a convergent assembly of the tricyclic labdane‐type core from pre‐functionalized cyclic building blocks. Stereoselective Michael addition enabled the fragment coupling with excellent control over three newly created contiguous stereocenters, all‐carbon quaternary centers included. Silyl enol ether‐promoted ring‐opening metathesis paired with ring closure were the other key steps enabling concise assembly of the tricyclic core. Late‐stage functionalization sequences transformed the tricyclic intermediates into a set of different forskolin‐like molecules. The modular nature of the synthetic scheme described herein has the potential to become a general platform for the preparation of analogs of forskolin and other complex tricyclic labdanes.
RNA Probes for Visualization of Sarcin/ricin Loop Depurination without Background Fluorescence
Authors: Klimek Robin , Kaiser Christoph , Murmann Nina S. , Kaltenschnee Nina , Spanò Teresa , Wachtveitl Josef , Schuman Erin M. , Heckel Alexander 
Published: November 2022

AbstractProtein synthesis via ribosomes is a fundamental process in all known living organisms. However, it can be completely stalled by removing a single nucleobase (depurination) at the sarcin/ricin loop of the ribosomal RNA. In this work, we describe the preparation and optimization process of a fluorescent probe that can be used to visualize depurination. Starting from a fluorescent thiophene nucleobase analog, various RNA probes that fluoresce exclusively in the presence of a depurinated sarcin/ricin‐loop RNA were designed and characterized. The main challenge in this process was to obtain a high fluorescence signal in the hybridized state with an abasic RNA strand, while keeping the background fluorescence low. With our new RNA probes, the fluorescence intensity and lifetime can be used for efficient monitoring of depurinated RNA.
Association between body mass index and localized prostate cancer management and disease‐specific quality of life
Authors: Samora Nathan L. , Wallis Christopher J. D. , Huang Li‐Ching , Tallman Jacob E. , Zhao Zhiguo , Hoffman Karen , Morgans Alicia , Cooperberg Matthew , Goodman Michael , Greenfield Sheldon , Hamilton Ann S. , Hashibe Mia , Kaplan Sherrie , O'Neil Brock , Paddock Lisa E. , Stroup Antoinette , Wu Xiao‐Cheng , Koyama Tatsuki , Penson David F. , Barocas Daniel A. 
Published: November 2022

AbstractPurposeThe purpose of this work is to describe the association between body mass index (BMI) and (1) management option for localized prostate cancer (PCa) and (2) disease‐specific quality of life (ds‐QoL) after treatment or active surveillance.Subjects/patients and methodsWe analysed data from men with localized PCa managed with radical prostatectomy (RP), radiation therapy (RT), or active surveillance (AS) in a prospective, population‐based cohort study. We evaluated the association between BMI and management option with multivariable multinomial logistic regression analysis. The association between BMI and ds‐QoL was assessed using multivariable longitudinal linear regression. Regression models were adjusted for baseline domain scores, demographics, and clinicopathologic characteristics.ResultsA total of 2378 men were included (medians [quartiles]: age 64 [59–69] years; BMI 27 kg/m2; 77% were non‐Hispanic white); 29% were obese (BMI ≥ 30). Accounting for demographic and clinicopathologic features, BMI ≥ 28 kg/m2 was inversely associated with the likelihood of receiving RP (compared with RT) and became statistically significant at BMI ≥ 33 kg/m2 (maximum adjusted relative risk ratio = 0.80, 95% CI 0.67 to 0.95, p = 0.013 for BMI ≥ 33 vs. 25). Conversely, BMI was not significantly associated with the likelihood of receiving AS compared with RT. After stratification by management option, obese men who underwent definitive treatment were not found to have clinically worse ds‐QoL. Obese men initially on AS appeared to have worse urinary incontinence than nonobese men, but this was not significant on an as‐treated sensitivity analysis.ConclusionsAmong men with localized PCa, those with BMI ≥ 33 kg/m2 were less likely to receive surgery than radiation. Obesity was not associated with ds‐QoL in men undergoing definitive treatment, nor in men who remained on AS.
Effects of Charged Lipids on Giant Unilamellar Vesicle Fusion and Inner Content Mixing via Freeze‐Thawing
Authors: Shimomura Ayu , Ina Shiori , Oki Masaya , Tsuji Gakushi 
Published: November 2022

AbstractFusion between giant unilamellar vesicles (GUVs) can incorporate and mix components of biochemical reactions. Recently, GUV fusion induced by freeze‐thawing (F/T) was employed to construct artificial cells that can easily and repeatedly fuse GUVs with efficient content mixing. However, GUVs were ruptured during F/T, and the inner contents leaked. Herein, we investigated the effects of charged lipids on GUV fusion via F/T. The presence of 10 %‐50 % (w/w%) negatively charged lipids in GUV membranes, mainly composed of the neutral charged lipid 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (POPC), improved resistance to GUV rupture and decreased inner content leakage. Furthermore, we found that the presence of positively charged lipids in GUV membranes elevated GUV rupture compared with F/T between GUVs containing POPC alone. Modified GUVs may better incorporate nutrients and lipid membranes with less damage following GUV fusion via F/T, providing an improved artificial model.
Mesenchymal stem cells: A novel treatment option for primary sclerosing cholangitis
Authors: Lightner Amy L. , Dadgar Neda , Vaidya Anil , Simon Robert , Fulmer Clifton , Siddiki Hassan , Narayanan Menon K. V. , Liu Peter , Matthew Walsh R. 
Published: November 2022

AbstractPrimary sclerosing cholangitis (PSC) is a progressive liver disease for which there is no effective therapy. Hepatocytes and cholangiocytes from a PSC patient were cocultured with mesenchymal stem cells (MSCs) to assess in vitro change. A single patient with progressive PSC was treated with 150 million MSCs via direct injection into the common bile duct. Coculture of MSCs with cholangiocytes and hepatocytes showed in vitro improvement. Local delivery of MSCs into a single patient with progressive PSC was safe. Radiographic and endoscopic evaluation showed stable distribution of multifocal structuring in the early postoperative period. MSCs may be effective for the treatment of PSC.
Prediction of functional results of percutaneous coronary interventions with virtual stenting and quantitative flow ratio
Authors: Lee Hyun‐Jong , Mejía‐Rentería Hernán , Escaned Javier , Doh Joon‐Hyung , Lee Joo Myung , Hwang Doyeon , Yuasa Sonoka , Choi Ki Hong , Jang Ho‐Jun , Jeon Ki‐Hyun , Lee Juneyoung , Nam Chang‐Wook , Shin Eun‐Seok , Koo Bon‐Kwon 
Published: November 2022

AbstractBackgroundThe clinical value of residual quantitative flow ratio (rQFR), a novel function of QFR technique, is unknown.AimWe investigated the clinical value of rQFR, aimed to predict residual ischemia after virtual percutaneous coronary intervention (vPCI).MethodsThis is a substudy of the COE‐PERSPECTIVE registry, which investigated the prognostic value of post‐PCI fractional flow reserve (FFR). From pre‐PCI angiograms, QFR and rQFR were analyzed and their diagnostic performance was assessed at blinded fashion using pre‐PCI FFR and post‐PCI FFR as reference, respectively. The prognostic value of rQFR after vPCI was assessed according to vessel‐oriented composite outcome (VOCO) at 2 years.ResultsWe analyzed 274 patients (274 vessels) with FFR‐based ischemic causing lesions (49%) from 555 screened patients. Pre‐PCI QFR and FFR were 0.63 ± 0.10 and 0.66 ± 0.11 (R = 0.756, p < 0.001). rQFR after vPCI and FFR after real PCI were 0.93 ± 0.06 and 0.86 ± 0.07 (R = 0.528, p < 0.001). The mean difference between rQFR and post‐PCI FFR was 0.068 (95% limit of agreement: −0.05 to 0.19). Diagnostic performance of rQFR to predict residual ischemia after PCI was good (area under the curve [AUC]: 0.856 [0.804−0.909], p < 0.001). rQFR predicted well the incidence of 2‐year VOCO after index PCI (AUC: 0.712 [0.555−0.869], p = 0.041), being similar to that of actual post‐PCI FFR (AUC: 0.691 [0.512−0.870], p = 0.061). rQFR ≤0.89 was associated with increased risk of 2‐year VOCO (hazard ratio [HR]: 12.9 [2.32−71.3], p = 0.0035). This difference was mainly driven by a higher rate of target vessel revascularization (HR: 16.98 [2.33−123.29], p = 0.0051).ConclusionsrQFR estimated from pre‐PCI angiography and virtual coronary stenting mildly overestimated functional benefit of PCI. However, it well predicted suboptimal functional result and long‐term vessel‐related clinical events.Clinical Trial RegistrationInfluence of fractional flow reserve on the Clinical OutcomEs of PERcutaneouS Coronary Intervention (COE‐PESPECTIVE) Registry, NCT01873560.
Separation of Tellurium from Metal Chalcogenides through Mild Anhydrous Chlorination
Authors: Uible Madeleine C. , Kieser Jerod M. , Bart Suzanne C. 
Published: November 2022

AbstractThe separation of tellurium from cadmium telluride is examined using a unique combination of mild, anhydrous chlorination and complexation of the subsequent tellurium tetrachloride with 3,5‐di‐tert‐butylcatecholate ligands (dtbc). The resulting tellurium complex, Te(dtbc)2, is isolated in moderate yield and features a 103to 104reduction in cadmium content, as provided by XRF and ICP‐MS analysis. Similar results were obtained from zinc telluride. A significant separation between Te, Se, and S was observed after treating a complex mixture of metal chalcogenides with this protocol. These three tunable steps can be applied for future applications of CdTe photovoltaic waste.
Observation and Characterization of the Hg‐O Diatomic Molecule: A Matrix‐Isolation and Quantum‐Chemical Investigation
Authors: Andrews Lester S. , Tsegaw Yetsedaw A. , Cho Han‐Gook , Riedel Sebastian 
Published: November 2022

AbstractMercuric oxide is a well‐known and stable solid, but the diatomic molecule Hg−O is very fragile and does not survive detection in the gas phase. However, laser ablation of Hg atoms from a dental amalgam alloy target into argon or neon containing about 0.3 % of 16O2 or of 18O2 during their condensation into a cryogenic matrix at 4 K allows the formation of O atoms which react on annealing to make ozone and new IR absorptions in solid argon at 521.2 cm−1 for Hg‐16O or at 496.4 cm−1 for Hg‐18O with the oxygen isotopic frequency ratio 521.2/496.4=1.0499. Solid neon gives a 529.0 cm−1 absorption with a small 7.8 cm−1 blue shift. CCSD(T) calculations found 594 cm−1 for Hg16O and 562 cm−1 for Hg18O (frequency ratio=1.0569). Such calculations usually produce harmonic frequencies that are slightly higher than the anharmonic (observed) values, which supports their relationship. These observed frequencies have the isotopic shift predicted for Hg−O and are within the range of recent high‐level frequency calculations for the Hg−O molecule. Spectra for the related mercury superoxide and ozonide species are also considered for the first time.
Direct Aroylation of Olefins through a Cobalt/Photoredox‐Catalyzed Decarboxylative and Dehydrogenative Coupling with α‐Oxo Acids
Authors: Davies Alex M. , D. Hernandez Rafael , Tunge Jon A. 
Published: November 2022

AbstractA photoredox/cobalt dual catalytic procedure has been developed that allows benzoylation of olefins. Here the photoredox catalyst effects the decarboxylation of α‐ketoacids to form benzoyl radicals. After addition of this radical to styrenes, the cobalt catalyst abstracts a H‐atom. Hydrogen evolution from the putative cobalt hydride intermediate allows a Heck‐like aroylation without the need for a stoichiometric oxidant. Mechanistic studies reveal that electronically different styrenes lead to a curved Hammett plot, thus suggesting a change in product‐determining step in the catalytic mechanism.
Electrophile‐Promoted Nucleophilic Cyclization of 2‐Alkynylindoles to Give 4‐Substituted Oxazinoindolones
Authors: Leonel Guilherme , Klann Isabella , Back Davi F. , Iglesias Bernardo A. , Nogueira Cristina W. , Zeni Gilson 
Published: November 2022

AbstractA method for the synthesis of 4‐organoselanyl oxazinoindolone derivatives by the cascade cyclization of N‐(alkoxycarbonyl)‐2‐alkynylindoles using iron(III) chloride and diorganyl diselenides as promoters was developed. This protocol was applied to a series of N‐(alkoxycarbonyl)‐2‐alkynylindoles containing different substituents. The reaction conditions also tolerated a variety of diorganyl diselenides having both electron donating and electron withdrawing groups. However, the reaction did not work for diorganyl disulfides and ditellurides. The reaction mechanism seems to proceed via an ionic pathway and the cooperative action between iron(III) chloride and diorganyl diselenides is crucial for successful cyclization. We also found that using the same starting materials, by simply changing the electrophilic source to iodine, led to the formation of 4‐iodo‐oxazinoindolones. The high reactivity of Csp2−Se and Csp2−I bonds were tested under cross‐coupling conditions leading to the preparation of a new class of functionalized indole derivatives. In addition, the absorption, emission and electrochemical properties of 4‐organoselanyl oxazinoindolones showed an important relationship with the substituents of the aromatic rings. The advantages of the methodology include the use of electrophilic to promote the cyclization reaction and functionalization of the indole ring, and the electronic properties presented by the prepared compounds can be exploited as probes, analyte detectors and optical materials.
Design and Synthesis of a Ferrocene‐Based Diol Library and Application in the Hetero‐Diels‐Alder Reaction
Authors: Cunningham Laura , Guiry Patrick J. 
Published: November 2022

AbstractDiol scaffolds have been utilized as highly effective catalysts and ligands in a wide range of catalytic asymmetric transformations. For scaffolds to be successful as broadly used motifs, they should be prepared cheaply through facile routes and be easily handled. Herein, the synthesis of a family of planar chiral diols based on a modular and robust three‐step route is described, which yields catalytically active diols in >99 % de and >99 % ee, with up to seven different chiral elements. These diols have been characterized by X‐ray crystallographic analysis, which provides clear evidence for the likely transition state when applied in the asymmetric hetero‐Diels‐Alder reaction. Without altering the stereochemistry of the catalyst backbone, it is possible to access both enantiomers of the product by varying the substitution of the catalyst at the α‐position.
Ion Migration and Accumulation in Halide Perovskite Solar Cells†
Authors: Zuo Lijian , Li Zexin , Chen Hongzheng 
Published: November 2022

Comprehensive SummaryThe halide perovskite semiconductors‐based solar cells (PVSCs) show great promise as next‐generation renewable energy sources, with the merits of low cost, high performance, good flexibility, etc. A major difference distinguishing the perovskite semiconductors from others lies in their ionic feature. This intrinsic property induces “freely‐moving” ions to migrate and accumulate in the perovskite films and devices under different external stresses. As a charge carrier, these processes will strongly couple with the electronic process, and dramatically affect the performance and stability of PVSCs. This review summarizes and discusses the recent progresses and fundamental understandings of ion migration and accumulation behaviors in PVSCs. First, the basic principles of the general ion migration are reviewed. Second, following the fundamental understandings, the critical factors, e.g., ion migration activation energy, ion density, ion diffusion coefficient, etc., are extracted to understand the ion migration and accumulation in perovskite film. Third, the principles governing ion accumulation behaviors under different external stresses are discussed. Finally, the effect of ion migration and accumulation on band bending, and device performance is presented. Therefore, we hope this review provides a tutorial and insightful perspective regarding the most prominent ionic feature of perovskite semiconductors and their application for photovoltaics.
Nucleophilic Radicals as Hydrogen Atom Abstractors in C(sp3)‐H Functionalization Reactions
Authors: Li Tao , Li Jian , Huo Haohua 
Published: November 2022

Comprehensive SummaryHydrogen atom transfer (HAT) is an elementary mechanistic step in organic synthesis. The photoredox‐catalyzed HAT has transformed organic synthesis by enabling the activation and subsequent cross‐coupling of traditionally inert yet ubiquitous C(sp3)‐H bonds. While diverse electrophilic radical species have proven to be exceptionally effective HAT catalysts for selective functionalization of hydridic and electron‐neutral C(sp3)‐H, general methods using nucleophilic radicals as hydrogen atom abstractors in C(sp3)‐H functionalization remain relatively underdeveloped. Herein, we highlight two creative and strategic advances in addressing this long‐standing challenge, and emphasize reaction achievements, mechanistic insights, potential, and future challenges.
Design and Synthesis of N‐Alkylaniline‐Substituted Low Band‐Gap Electron Acceptors for Photovoltaic Application
Authors: Li Jiayao , Li Hao , Ma Lijiao , Zhang Shaoqing , Hou Jianhui 
Published: November 2022

Comprehensive SummaryA novel electron donating unit, namely N‐octyl‐N‐phenyl‐thiophene (OPT), was designed in preparing electron acceptors with non‐fused ring chemical structures. By introducing different functional atoms/groups into the para‐position of phenyl in the OPT units, three non‐fused ring acceptors (NFREAs), C8‐2F, FC8‐2F and MeC8‐2F, were synthesized. The absorption spectrum of the three acceptors can be extended to about 950 nm with band‐gaps of 1.28—1.32 eV due to the strong electron donating ability of OPT. The frontier molecular orbital distribution of OPT based molecules obtained by quantum chemistry calculation results reveals that their energy alignment can be finely tuned to meet different requirements. Moreover, by changing the substituents on the OPT units, their Flory‐Huggins interaction parameter (χ) with the donor will be greatly influenced and different phase separation behavior can be accomplished. After blended with PBDB‐TF, the FC8‐2F‐based cell yields short circuit current density (Jsc) of 23.21 mA·cm–2, fill factor (FF) of 72.11% and the highest power conversion efficiency (PCE) of 12.42%. This work provides a new pathway for molecular design of new NFREAs, and demonstrates the application potential of OPT unit in realizing low band‐gap photovoltaic materials.
Design and Synthesis of Al7Ni2 Heterometallic Clusters Based on Metal Substitution and Ligands Protection Strategies†
Authors: Liu Ya‐Jie , Cui Li‐Min , Fang Wei‐Hui , Zhang Jian 
Published: November 2022

Comprehensive SummaryThe synthesis of heterometallic aluminum‐based materials is challenging yet attractive, due to their potential applications in optics, catalysis, magnetism and semiconductor device. We have now successfully synthesized two Al7Ni2 heterometallic clusters bearing different peripheral alkoxide ligands through a heterometal substitution strategy. Single crystal structure analysis shows that they are isostructural, only with slight differences in the number of OH and guests. We found that benzyl alkoxides protected Al7Ni2 cluster compound is more stable in H2O and various organic solvents when compared with ethoxides coordinated one. Moreover, it can be used as a reliable catalyst in aldol condensation reactions with higher activity. This work provides a new method for the design of stable crystalline heterometallic aluminum oxo compounds and reveals their excellent catalysis performance.
Lightweight, secure, efficient, and dynamic scheme for mutual authentication of devices in Internet‐of‐Things‐Fog environment
Authors: Jain Usha , Pirasteh Saied , Hussain Muzzammil 
Published: November 2022

AbstractSecurity is a major challenge in the design and implementation of Internet‐of‐Things (IoT)‐Fog networks and it can be resolved by an efficient authentication mechanism. As the devices have limited resources like battery, processor and memory, any mechanism designed for IoT‐Fog has to be resource aware. In this paper, we proposed a lightweight, secure, dynamic, and efficient scheme for mutual authentication of devices in IoT‐Fog networks. In the proposed scheme, the devices obtain a primary security value from the cloud server and this acquired primary security value is used to authenticate them mutually. We used XOR operation, concatenation operation, one‐way hash function and symmetric key cryptography to accommodate resource constraint nature of devices. The proposed scheme has been analyzed for security formally using BAN logic and automated using Automated Validation of Internet Security Protocols and Applications & ProVerif tools and it is proved that the proposed scheme is secure from the known attacks. The comparative analysis of the proposed scheme with the existing schemes proved that it is better than existing schemes and its experimental analysis showed that it consumes 20%–30% less energy compared to existing schemes. Our proposed scheme is better with reference to security and efficient in respect of computation, communication, and storage overheads.
A Constitutive Model for Polycrystalline U–Nb Alloy Considering Multiple Phase Transition
Authors: Liu Tingyi 
Published: November 2022

AbstractThis study proposes a thermomechanical constitutive model for the shape memory effect of U–12.8 at.% Nb (U–Nb) alloy. The phenomenological model uses two variables for transformation. A transitional evolution function based on dissipative force is constructed, which removes the consistency condition. This improvement leads to a natural smoothness of all transitions, without any specifically defined hardening function. In addition, hysteresis is a natural result of the same reference force being converted forward and backward, and defining two different mixing energies is not necessary. The effect of strain rate is captured in the same frame by a function of the transition coefficient. This paper designs a robust and efficient numerical algorithm for the ordinary differential equation system. The model is validated by several special load cases. The simulation results are then compared with previous experimental data in the paper.