bluuebunny/crossref_metadata_2025_split huggingface dataset:
trans‐Selective Aryldifluoroalkylation of Endocyclic Enecarbamates and Enamides by Nickel Catalysis
Authors: Xu Chang , Cheng Ran , Luo Yun‐Cheng , Wang Ming‐Kuan , Zhang Xingang 
Published: July 2020

AbstractEfficient methods for the dicarbofuntionalization of the cyclic alkenes 2‐pyrroline and 2‐azetine are limited. Particularly, the dicarbofunctionalization of endocyclic enecarbamates to achieve fluorinated compounds remains an unsolved issue. Reported here is a nickel‐catalyzed trans‐selective dicarbofunctionalization of N‐Boc‐2‐pyrroline and N‐Boc‐2‐azetine, a class of endocyclic enecarbamates previously unexplored for transition metal catalyzed dicarbofunctionalization. The reaction can be extended to six‐ and seven‐membered endocyclic enamides. A variety of arylzinc reagents and bromodifluoroacetate, and its derivatives, undergo the reaction, providing straightforward and efficient access to an array of pyrrolidine‐ and azetidine‐containing fluorinated amino acids and oligopeptides, which may have applications in the life sciences.
High‐Fidelity End‐Functionalization of Poly(ethylene glycol) Using Stable and Potent Carbamate Linkages
Authors: Shi Shengyu , Yao Chenzhi , Cen Jie , Li Lei , Liu Guhuan , Hu Jinming , Liu Shiyong 
Published: July 2020

AbstractCommercial PEG‐amine is of unreliable quality, and conventional PEG functionalization relies on esterification and etherification steps, suffering from incomplete conversion, harsh reaction conditions, and functional‐group incompatibility. To solve these challenges, we propose an efficient strategy for PEG functionalization with carbamate linkages. By fine‐tuning terminal amine basicity, stable and high‐fidelity PEG‐amine with carbamate linkage was obtained, as seen from the clean MALDI‐TOF MS pattern. The carbamate strategy was further applied to the synthesis of high‐fidelity multi‐functionalized PEG with varying reactive groups. Compared to with an ester linkage, amphiphilic PEG‐PS block copolymers bearing carbamate junction linkage exhibits preferential self‐assembly tendency into vesicles. Moreover, nanoparticles of the latter demonstrate higher drug loading efficiency, encapsulation stability against enzymatic hydrolysis, and improved in vivo retention at the tumor region.
Beyond the Polysulfide Shuttle and Lithium Dendrite Formation: Addressing the Sluggish Sulfur Redox Kinetics for Practical High‐Energy Li‐S Batteries
Authors: Zhao Chen , Xu Gui‐Liang , Zhao Tianshou , Amine Khalil 
Published: July 2020

AbstractElectrolyte modulation simultaneously suppresses polysulfide the shuttle effect and lithium dendrite formation of lithium–sulfur (Li‐S) batteries. However, the sluggish S redox kinetics, especially under high S loading and lean electrolyte operation, has been ignored, which dramatically limits the cycle life and energy density of practical Li‐S pouch cells. Herein, we demonstrate that a rational combination of selenium doping, core–shell hollow host structure, and fluorinated ether electrolytes enables ultrastable Li stripping/plating and essentially no polysulfide shuttle as well as fast redox kinetics. Thus, high areal capacity (>4 mAh cm−2) with excellent cycle stability and Coulombic efficiency were both demonstrated in Li metal anode and thick S cathode (4.5 mg cm−2) with a low electrolyte/sulfur ratio (10 μL mg−1). This research further demonstrates a durable Li‐Se/S pouch cell with high specific capacity, validating the potential practical applications.
Highly Efficient and Air‐Stable Lanthanide EuII Complex: New Emitter in Organic Light Emitting Diodes
Authors: Zhan Ge , Wang Liding , Zhao Zifeng , Fang Peiyu , Bian Zuqiang , Liu Zhiwei 
Published: July 2020

AbstractLuminescent EuII complexes with a characteristic 5d–4f transition have potential applications in many fields. However, their instability in ambient conditions impedes further exploration and application. Herein, we report two new EuII complexes, bis[hydrotris(3‐trifluoromethylpyrazolyl)borate]europium(II) (Eu‐1) and bis[hydrotris(3‐methylpyrazolyl)borate]europium(II) (Eu‐2). Intriguingly, the blue emissive Eu‐1 showed high air stability arising from fluorine protection and close molecular packing, as maintaining a photoluminescence quantum yield (PLQY) of 91 % (initial 96 %) upon exposure to air over 2200 hours. While the orange emissive Eu‐2 showed a maximum luminance of 30620 cd m−2, and a maximum external quantum efficiency (EQE) of 6.5 %, corresponding to an exciton utilization efficiency around 100 % in organic light‐emitting diodes (OLEDs). These results could inspire further research on stable and efficient EuII complexes and their application in OLEDs.
Interfacially Bridging Covalent Network Yields Hyperstable and Ultralong Virus‐Based Fibers for Engineering Functional Materials
Authors: Zhou Kun , Zhou Yihao , Yang Hongchao , Jin Huile , Ke Yonggang , Wang Qiangbin 
Published: July 2020

AbstractWe present a strategy of interfacially bridging covalent network within tobacco mosaic virus (TMV) virus‐like particles (VLPs). We arranged T103C cysteine to laterally conjugate adjacent subunits. In the axis direction, we set A74C mutation and systematically investigated candidate from E50C to P54C as the other thiol function site, for forming longitudinal disulfide bond chains. Significantly, the T103C‐TMV‐E50C‐A74C shows the highest robustness in assembly capability and structural stability with the largest length, for TMV VLP to date. The fibers with lengths from several to a dozen of micrometers even survive under pH 13. The robust nature of this TMV VLP allows for reducer‐free synthesis of excellent electrocatalysts for application in harshly alkaline hydrogen evolution.
Synthesis, characterization, molecular docking, and biological activities of coumarin–1,2,3‐triazole‐acetamide hybrid derivatives
Authors: Sepehri Nima , Mohammadi‐Khanaposhtani Maryam , Asemanipoor Nafise , Hosseini Samanesadat , Biglar Mahmood , Larijani Bagher , Mahdavi Mohammad , Hamedifar Haleh , Taslimi Parham , Sadeghian Nastaran , Gulcin Ilhami 
Published: July 2020

AbstractCoumarins and their derivatives are receiving increasing attention due to numerous biochemical and pharmacological applications. In this study, a series of novel coumarin–1,2,3‐triazole‐acetamide hybrids was tested against some metabolic enzymes including α‐glycosidase (α‐Gly), α‐amylase (α‐Amy), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), human carbonic anhydrase I (hCA I), and hCA II. The new coumarin–1,2,3‐triazole‐acetamide hybrids showed Ki values in the range of 483.50–1,243.04 nM against hCA I, 508.55–1,284.36 nM against hCA II, 24.85–132.85 nM against AChE, 27.17–1,104.36 nM against BChE, 590.42–1,104.36 nM against α‐Gly, and 55.38–128.63 nM against α‐Amy. The novel coumarin–1,2,3‐triazole‐acetamide hybrids had effective inhibition profiles against all tested metabolic enzymes. Also, due to the enzyme inhibitory effects of the new hybrids, they are potential drug candidates to treat diseases such as epilepsy, glaucoma, type‐2 diabetes mellitus (T2DM), Alzheimer's disease (AD), and leukemia. Additionally, these inhibition effects were compared with standard enzyme inhibitors like acetazolamide (for hCA I and II), tacrine (for AChE and BChE), and acarbose (for α‐Gly and α‐Amy). Also, those coumarin–1,2,3‐triazole‐acetamide hybrids with the best inhibition score were docked into the active site of the indicated metabolic enzymes.
Cas9 Cuts and Consequences; Detecting, Predicting, and Mitigating CRISPR/Cas9 On‐ and Off‐Target Damage
Authors: Newman Anthony , Starrs Lora , Burgio Gaetan 
Published: July 2020

AbstractLarge deletions and genomic re‐arrangements are increasingly recognized as common products of double‐strand break repair at Clustered Regularly Interspaced, Short Palindromic Repeats ‐ CRISPR associated protein 9 (CRISPR/Cas9) on‐target sites. Together with well‐known off‐target editing products from Cas9 target misrecognition, these are important limitations, that need to be addressed. Rigorous assessment of Cas9‐editing is necessary to ensure validity of observed phenotypes in Cas9‐edited cell‐lines and model organisms. Here the mechanisms of Cas9 specificity, and strategies to assess and mitigate unwanted effects of Cas9 editing are reviewed; covering guide‐RNA design, RNA modifications, Cas9 modifications, control of Cas9 activity; computational prediction for off‐targets, and experimental methods for detecting Cas9 cleavage. Although recognition of the prevalence of on‐ and off‐target effects of Cas9 editing has increased in recent years, broader uptake across the gene editing community will be important in determining the specificity of Cas9 across diverse applications and organisms.
Time to definitive care within major trauma networks in England
Authors: Haslam N R , Bouamra O , Lawrence T , Moran C G , Lockey D J 
Published: July 2020

Abstract

Background
Significant mortality improvements have been reported following the implementation of English trauma networks. Timely transfer of seriously injured patients to definitive care is a key indicator of trauma network performance. This study evaluated timelines from emergency service (EMS) activation to definitive care between 2013 and 2016.

Methods
An observational study was conducted on data collected from the UK national clinical audit of major trauma care of patients with an Injury Severity Score above 15. Outcomes included time from EMS activation to: arrival at a trauma unit (TU) or major trauma centre (MTC); to CT; to urgent surgery; and to death.

Results
Secondary transfer was associated with increased time to urgent surgery (median 7·23 (i.q.r. 5·48–9·28) h versus 4·37 (3·00–6·57) h for direct transfer to MTC; P &lt; 0·001) and an increased crude mortality rate (19·6 (95 per cent c.i. 16·9 to 22·3) versus 15·7 (14·7 to 16·7) per cent respectively). CT and urgent surgery were performed more quickly in MTCs than in TUs (2·00 (i.q.r. 1·55–2·73) versus 3·15 (2·17–4·63) h and 4·37 (3·00–6·57) versus 5·37 (3·50–7·65) h respectively; P &lt; 0·001). Transfer time and time to CT increased between 2013 and 2016 (P &lt; 0·001). Transfer time, time to CT, and time to urgent surgery varied significantly between regional networks (P &lt; 0·001).

Conclusion
Secondary transfer was associated with significantly delayed imaging, delayed surgery, and increased mortality. Key interventions were performed more quickly in MTCs than in TUs.
Mandibular canal vs. inferior alveolar canal: Evidence‐based terminology analysis
Authors: Iwanaga Joe , Matsushita Yuki , Decater Tess , Ibaragi Soichiro , Tubbs R. Shane 
Published: July 2020

AbstractIntroductionThe mandibular canal, as it was formerly named in Terminologia Anatomica (TA), has also been called the inferior alveolar (nerve) canal in many scientific publications. This study was conducted to investigate how these terms have been understood in different regions and different areas of expertise and to discuss the appropriate future application of the term “mandibular canal.”MethodsA literature search was conducted using PubMed, and articles using different terms for this structure were classified into two groups, inferior alveolar canal/inferior alveolar nerve canal (IAC/IANC) and the mandibular canal (MC). The 50 most recent articles in each group were included. Publication year, journal title, country of the first author, and affiliation of all authors were recorded in both groups for all 100 articles.ResultsThere was a significant difference between the IAC/IANC and MC groups in the numbers of anatomy journals, other journals, and anatomy affiliations. Turkey published most frequently with a total of 15 articles, followed by Iran with 10 articles, and China/India/United States with seven each. When the six countries of the first author that had three or more publications in each group were compared, only Turkey appeared in both groups; otherwise, different countries were in the two groups.ConclusionsBased on the results of this analysis, and considering that the tentative new term “inferior alveolar foramen” is used in the latest TA, we suggest that the mandibular canal should be renamed the “inferior alveolar canal.”
Switches of SOX17 and SOX2 expression in the development of squamous metaplasia and squamous intraepithelial lesions of the uterine cervix
Authors: Moshi Jobran M. , Hoogduin Klaas J. , Ummelen Monique , Henfling Mieke E. R. , van Engeland Manon , Wouters Kim A. D. , Stoop Hans , Demers Imke , Looijenga Leendert H. J. , Ramaekers Frans C. S. , Hopman Anton N. H. 
Published: July 2020

AbstractAimsThe dynamics and topographical distribution of SOX17 and SOX2 expression was studied in the transformation zone (TZ) of the uterine cervix. This TZ is a dynamic area where switches from glandular into squamous epithelium can be recognized, new squamocolumnar junctions are formed, and premalignant lesions originate. SOX17 and SOX2 show mutually exclusive expression patterns in the normal uterine cervix, with SOX2 being exclusively found in squamous epithelium, while SOX17 is detected in endocervical columnar cells and reserve cells.Methods and ResultsNormal cervices and squamous intraepithelial lesions (SIL) were studied with immunohistochemistry, methylation of SOX17, human papilloma virus (HPV) genotyping, and in situ hybridization. In the TZ squamous metaplasia originating from these reserve cells can still show SOX17 expression, while also remnants of SOX17‐positive immature metaplasia can be recognized in the normal squamous epithelium. SOX17 expression is gradually lost during maturation, resulting in the exclusive expression of SOX2 in the majority of (SIL). This loss of SOX17 expression is independent of methylation of the CpG island in its promotor region. HPV can be detected in SOX17‐positive immature metaplastic regions in the immediate vicinity of SOX2‐positive SIL, suggesting that switches in SOX17 and 2 expression can occur upon HPV infection.ConclusionsThis switch in expression, and the strong association between the distribution of reserve cells and squamous areas within the columnar epithelium in the TZ, suggests that reserve cell proliferations, next to basal cells in the squamous epithelium, are potential targets for the formation of squamous lesions upon viral infection.
Population bias in somatic measurement of microsatellite instability status
Authors: Saul Michelle , Poorman Kelsey , Tae Hongseok , Vanderwalde Ari , Stafford Phillip , Spetzler David , Korn Wolfgang M. , Gatalica Zoran , Swensen Jeff 
Published: July 2020

AbstractMicrosatellite instability (MSI) is a key secondary effect of a defective DNA mismatch repair mechanism resulting in incorrectly replicated microsatellites in many malignant tumors. Historically, MSI detection has been performed by fragment analysis (FA) on a panel of representative genomic markers. More recently, using next‐generation sequencing (NGS) to analyze thousands of microsatellites has been shown to improve the robustness and sensitivity of MSI detection. However, NGS‐based MSI tests can be prone to population biases if NGS results are aligned to a reference genome instead of patient‐matched normal tissue. We observed an increased rate of false positives in patients of African ancestry with an NGS‐based diagnostic for MSI status utilizing 7317 microsatellite loci. We then minimized this bias by training a modified calling model that utilized 2011 microsatellite loci. With these adjustments 100% (95% CI: 89.1% to 100%) of African ancestry patients in an independent validation test were called correctly using the updated model. This poses not only a significant technical improvement but also has an important clinical impact on directing immune checkpoint inhibitor therapy.
Competing Roles of Two Kinds of Ligand during Nonclassical Crystallization of Pillared‐Layer Metal‐Organic Frameworks Elucidated Using Microfluidic Systems
Authors: Tanaka Yoko , Kitamura Yu , Kawano Ryuji , Shoji Kan , Hiratani Moe , Honma Tetsuo , Takaya Hikaru , Yoshikawa Hirofumi , Tsuruoka Takaaki , Tanaka Daisuke 
Published: July 2020

AbstractTo diversify metal‐organic frameworks (MOFs), multi‐component MOFs constructed from more than two kinds of bridging ligand have been actively investigated due to the high degree of design freedom afforded by the combination of multiple ligands. Predicting the synthesis conditions for such MOFs requires an understanding of the crystallization mechanism, which has so far remained elusive. In this context, microflow systems are efficient tools for capturing non‐equilibrium states as they facilitate precise and efficient mixing with reaction times that correspond to the distance from the mixing point, thus enabling reliable control of non‐equilibrium crystallization processes. Herein, we prepared coordination polymers with pillared‐layer structures and observed the intermediates in the syntheses with an in‐situ measurement system that combines microflow reaction with UV/Vis and X‐ray absorption fine‐structure spectroscopies, thereby enabling their rapid nucleation to be monitored. Based on the results, a three‐step nonclassical nucleation mechanism involving two kinds of intermediate is proposed.
Linear Hydroaminoalkylation Products from Alkyl‐Substituted Alkenes
Authors: Warsitz Michael , Doye Sven 
Published: July 2020

AbstractThe regioselective conversion of alkyl‐substituted alkenes into linear hydroaminoalkylation products represents a strongly desirable synthetic transformation. In particular, such conversions of N‐methylamine derivatives are of great scientific interest, because they would give direct access to important amines with unbranched alkyl chains. Herein, we present a new one‐pot procedure that includes an initial alkene hydroaminoalkylation with an α‐silylated amine substrate and a subsequent protodesilylation reaction that delivers linear hydroaminoalkylation products with high selectivity from simple alkyl‐substituted alkenes. For that purpose, new titanium catalysts have been developed, which are able to activate the α‐C−H bond of more challenging α‐silylated amine substrates. In addition, a direct relationship between the ligand structure of the new catalysts and the obtained regioselectivity is described.
Synthesis and Insecticidal Evaluation of Novel Anthranilic Diamides Derivatives Containing 4‐Chlorine Substituted N‐Pyridylpyrazole
Authors: Li Huangong , Zhao Yangyang , Sun Pengwei , Gao Li , Li Yuxin , Xiong Lixia , Yang Na , Zhou Sha , Li Zhengming 
Published: July 2020

Main observation and conclusionTo search for potent insecticides targeting at ryanodine receptors (RyRs), a series of novel anthranilic diamides analogs containing 4‐chlorine N‐pyridylpyrazole were designed and synthesized. Their insecticidal activities were evaluated and the preliminary structure‐activity relationships (SARs) were discussed. The insecticidal results showed that some of the compounds (8a—8h, 8m, 8n) exhibited good larvicidal activities against oriental armyworm at 2.5 mg·L–1, and compound 8m possessed 60% insecticidal activity at 0.5 mg·L–1. For diamondback moth, 8m exhibited better activity than Chlorantraniliprole at a hundred fold preference. The calcium imaging technique experiment results suggested that compound 8m could increase the intracellular [Ca2+]i. With the neurons preincubated experiment, the results confirmed that the target of this series of compounds could be RyRs in the central larvae neurons of oriental armyworm. The results indicated that compound 8m could respond as a potential modulator of the insect ryanodine receptor.
Effect of Alkali Metal Cations on Length and Strength of Hydrogen Bonds in DNA Base Pairs
Authors: Stasyuk Olga A. , Solà Miquel , Swart Marcel , Fonseca Guerra Célia , Krygowski Tadeusz Marek , Szatylowicz Halina 
Published: July 2020

AbstractFor many years, non‐covalently bonded complexes of nucleobases have attracted considerable interest. However, there is a lack of information about the nature of hydrogen bonding between nucleobases when the bonding is affected by metal coordination to one of the nucleobases, and how the individual hydrogen bonds and aromaticity of nucleobases respond to the presence of the metal cation. Here we report a DFT computational study of nucleobase pairs interacting with alkali metal cations. The metal cations contribute to the stabilization of the base pairs to varying degrees depending on their position. The energy decomposition analysis revealed that the nature of bonding between nucleobases does not change much upon metal coordination. The effect of the cations on individual hydrogen bonds were described by changes in VDD charges on frontier atoms, H‐bond length, bond energy from NBO analysis, and the delocalization index from QTAIM calculations. The aromaticity changes were determined by a HOMA index.
Effects of embryo energy, egg size, and larval food supply on the development of asteroid echinoderms
Authors: Trackenberg Stacy N. , Richardson Emily L. , Allen Jonathan D. 
Published: July 2020

AbstractOrganisms have limited resources available to invest in reproduction, causing a trade‐off between the number and size of offspring. One consequence of this trade‐off is the evolution of disparate egg sizes and, by extension, developmental modes. In particular, echinoid echinoderms (sea urchins and sand dollars) have been widely used to experimentally manipulate how changes in egg size affect development. Here, we test the generality of the echinoid results by (a) using laser ablations of blastomeres to experimentally reduce embryo energy in the asteroid echinoderms (sea stars), Pisaster ochraceus and Asterias forbesi and (b) comparing naturally produced, variably sized eggs (1.7‐fold volume difference between large and small eggs) in A. forbesi. In P. ochraceus and A. forbesi, there were no significant differences between juveniles from both experimentally reduced embryos and naturally produced eggs of variable size. However, in both embryo reduction and egg size variation experiments, simultaneous reductions in larval food had a significant and large effect on larval and juvenile development. These results indicate that (a) food levels are more important than embryo energy or egg size in determining larval and juvenile quality in sea stars and (b) the relative importance of embryo energy or egg size to fundamental life history parameters (time to and size at metamorphosis) does not appear to be consistent within echinoderms.