bluuebunny/crossref_metadata_2025 huggingface dataset:
Sleep phenotype of individuals with autism spectrum disorder bearing mutations in the PER2 circadian rhythm gene
Authors: Hoang Ny , Yuen Ryan K.C. , Howe Jennifer , Drmic Irene , Ambrozewicz Patricia , Russell Carolyn , Vorstman Jacob , Weiss Shelly K. , Anagnostou Evdokia , Malow Beth A. , Scherer Stephen W.
Published: January 2021

The Per family of genes functions as a primary circadian rhythm maintenance in the brain. Mutations in PER2 are associated with familial advanced sleep‐phase syndrome 1 (FASPS1), and recently suggested in delayed sleep phase syndrome and idiopathic hypersomnia. The detection of PER2 variants in individuals with autism spectrum disorder (ASD) and without reported sleep disorders, has suggested a role of circadian‐relevant genes in the pathophysiology of ASD. It remains unclear whether these individuals may have, in addition to ASD, an undiagnosed circadian rhythm sleep disorder. The MSSNG database was used to screen whole genome sequencing data of 5,102 individuals with ASD for putative mutations in PER2. Families identified were invited to complete sleep phenotyping consisting of a structured interview and two standardized sleep questionnaires: the Pittsburgh Sleep Quality Index and the Morningness‐Eveningness Questionnaire. From 5,102 individuals with ASD, two nonsense, one frameshift, and one de novo missense PER2 variants were identified (0.08%). Of these four, none had a diagnosed sleep disorder. Three reported either a history of, or ongoing sleep disturbances, and one had symptoms highly suggestive of FASPS1 (as did a mutation carrier father without ASD). The individual with the missense variant did not report sleep concerns. The ASD and cognitive profiles of these individuals varied in severity and symptoms. The results support a possible role of PER2‐related circadian rhythm disturbances in the dysregulation of sleep overall and sometimes FASPS1. The relationship between dysregulated sleep and the pathophysiology of ASD require further exploration.
Regiodivergent Synthesis of Spirocyclic Compounds through Pd‐Catalyzed Regio‐ and Enantioselective [3+2] Spiroannulation
Authors: Trost Barry M. , Zuo Zhijun
Published: January 2021

A novel Pd0‐catalyzed highly regio‐ and enantioselective [3+2] spiroannulation reaction has been developed for rapid assembly of a new class of [5,5] spirocyclic carbo‐ and heterocycles. Notably, the regioselectivity could be dominated by fine‐tuning of the Pd‐π‐allyl intermediate. An array of coupling partners could be well‐tolerated with excellent regio‐, and enantioselectivities. Moreover, the potential application of this reaction was exemplified by several further transformations.
Chiral Self‐sorting of Giant Cubic [8+12] Salicylimine Cage Compounds
Authors: Wagner Philippe , Rominger Frank , Zhang Wen‐Shan , Gross Jürgen H. , Elbert Sven M. , Schröder Rasmus R. , Mastalerz Michael
Published: January 2021

Chiral self‐sorting is intricately connected to the complicated chiral processes observed in nature and no artificial systems of comparably complexity have been generated by chemists. However, only a few examples of purely organic molecules have been reported so far, where the self‐sorting process could be controlled. Herein, we describe the chiral self‐sorting of large cubic [8+12] salicylimine cage compounds based on a chiral TBTQ precursor. Out of 23 possible cage isomers only the enantiopure and amesocage were observed to be formed, which have been unambiguously characterized by single crystal X‐ray diffraction. Furthermore, by careful choice of solvent the formation ofmesocage could be controlled. With internal diameters ofdin=3.3–3.5 nm these cages are among the largest organic cage compounds characterized and show very high specific surface areas up to approx. 1500 m2 g−1after desolvation.
Colloidal Metal Nanocrystals with Metastable Crystal Structures
Authors: Janssen Annemieke , Nguyen Quynh N. , Xia Younan
Published: January 2021

In addition to the conventional knobs such as composition, size, shape, and defect structure, the crystal structure (or phase) of metal nanocrystals offers a new avenue for engineering their properties. Various strategies have recently been developed for the fabrication of colloidal metal nanocrystals in metastable phases different from their bulk counterparts. With a focus on noble metals, we begin with a brief introduction to their atomic packing, followed by a discussion about five major synthetic approaches to their colloidal nanocrystals in unconventional phases. We then highlight the success of synthesis in terms of mechanistic insights and experimental controls, as well as the enhanced catalytic properties. We end this Minireview with perspectives on the remaining issues and future opportunities.
Photochemically Activated Dimagnesium(I) Compounds: Reagents for the Reduction and Selective C−H Bond Activation of Inert Arenes
Authors: Jones Dafydd D. L. , Douair Iskander , Maron Laurent , Jones Cameron
Published: January 2021

The photochemical activation of dimagnesium(I) compounds, and subsequent high yielding, regioselective reactions with inert arenes are reported. Irradiating benzene solutions of [{(ArNacnac)Mg}2] (ArNacnac=[HC(MeCNAr)2]−; Ar=2,6‐diisopropylphenyl (Dip) or 2,4,6‐tricyclohexylphenyl (TCHP)) with blue or UV light, leads to double reduction of benzene and formation of the “Birch‐like” cyclohexadienediyl bridged compounds, [{(ArNacnac)Mg}2(μ‐C6H6)]. Irradiation of [{(DipNacnac)Mg}2] in toluene, and each of the three isomers of xylene, promoted completely regio‐ and chemo‐selective C−H bond activations, and formation of [(DipNacnac)Mg(Ar′)] (Ar′=meta‐tolyl; 2,3‐, 3,5‐ or 2,5‐dimethylphenyl), and [{(DipNacnac)Mg(μ‐H)}2]. Fluorobenzene was cleanly defluorinated by photoactivated [{(DipNacnac)Mg}2], leading to biphenyl and [{(DipNacnac)Mg(μ‐F)}2]. Computational studies suggest all reactions proceed via photochemically generated magnesium(I) radicals, which reduce the arene substrate, before C−H or C−F bond activation processes occur.
Frequency‐Upconverted Stimulated Emission by Up to Six‐Photon Excitation from Highly Extended Spiro‐Fused Ladder‐Type Oligo(p‐phenylene)s
Authors: Jiang Yi , Li King Fai , Gao Kun , Lin He , Tam Hoi Lam , Liu Yuan‐Yuan , Shu Yu , Wong Ka‐Leung , Lai Wen‐Yong , Cheah Kok Wai , Huang Wei
Published: January 2021

Frequency‐upconverted fluorescence and stimulated emission induced by multiphoton absorption (MPA) have attracted much interest. As compared with low‐order MPA processes, the construction of high‐order MPA processes is highly desirable and rather attractive, yet remains a formidable challenge due to its inherent low transition probability. We report the observation of the first experimental frequency‐upconverted fluorescence and stimulated emission by simultaneous six‐photon excitation in an organic molecular system. The well‐designed organic conjugated system based on cross‐shaped spiro‐fused ladder‐type oligo(p‐phenylene)s (SpL−z, z=1–3) manifests reasonably high MPA cross‐sections and brilliant luminescence emission simultaneously. The six‐photon absorption cross‐section of SpL‐3 with an extended π‐conjugation was evaluated as 8.67×10−169 cm12 s5 photon−5. Exceptionally efficient 2‐ to 6‐photon excited stimulated emission was achieved under near‐infrared laser excitation.
An Organic–Inorganic Hybrid Electrolyte as a Cathode Interlayer for Efficient Organic Solar Cells
Authors: Zhao Chaowei , Zhang Zhou , Han Faming , Xia Dongdong , Xiao Chengyi , Fang Jie , Zhang Yuefeng , Wu Binghui , You Shengyong , Wu Yonggang , Li Weiwei
Published: January 2021

An organic–inorganic hybrid electrolyte based on a cyclic Ti‐oxo cluster as the inorganic core and naphthalene‐based organic ammonium bromide salts as the electrolyte was developed with easy synthesis and low cost. The new hybrid electrolyte exhibits excellent solubility in methanol, aligned work function, good conductivity, and amorphous state in thin film, enabling its successful application as a cathode interlayer in organic solar cells with a high power conversion efficiency of 17.19 %. This work demonstrates that the hybrid electrolytes are a new kind of semiconductor, exhibiting promising applications in organic electronics.
Development of High‐Performance Pyrimidine Nucleoside and Oligonucleotide Diarylethene Photoswitches
Authors: Kolmar Theresa , Büllmann Simon M. , Sarter Christopher , Höfer Katharina , Jäschke Andres
Published: January 2021

Nucleosidic and oligonucleotidic diarylethenes (DAEs) are an emerging class of photochromes with high application potential. However, their further development is hampered by the poor understanding of how the chemical structure modulates the photochromic properties. Here we synthesized 26 systematically varied deoxyuridine‐ and deoxycytidine‐derived DAEs and analyzed reaction quantum yields, composition of the photostationary states, thermal and photochemical stability, and reversibility. This analysis identified two high‐performance photoswitches with near‐quantitative, fully reversible back‐and‐forth switching and no detectable thermal or photochemical deterioration. When incorporated into an oligonucleotide with the sequence of a promotor, the nucleotides maintained their photochromism and allowed the modulation of the transcription activity of T7 RNA polymerase with an up to 2.4‐fold turn‐off factor, demonstrating the potential for optochemical control of biological processes.
Fe‐Catalyzed Anaerobic Mukaiyama‐Type Hydration of Alkenes using Nitroarenes
Authors: Bhunia Anup , Bergander Klaus , Daniliuc Constantin Gabriel , Studer Armido
Published: January 2021

Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama‐type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe‐catalyzed anaerobic Markovnikov‐selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov‐selectivity. The method features large functional group tolerance and is also applicable for late‐stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.
Strain‐Modulated Reactivity: An Acidic Silane
Authors: Tretiakov Serhii , Witteman Léon , Lutz Martin , Moret Marc‐Etienne
Published: January 2021

Compounds of main‐group elements such as silicon are attractive candidates for green and inexpensive catalysts. For them to compete with state‐of‐the‐art transition‐metal complexes, new reactivity modes must be unlocked and controlled, which can be achieved through strain. Using a tris(2‐skatyl)methylphosphonium ([TSMPH3]+) scaffold, we prepared the strained cationic silane [TSMPSiH]+. In stark contrast with the generally hydridic Si−H bond character, it is acidic with an experimental pKaDMSO within 4.7–8.1, lower than in phenol, benzoic acid, and the few hydrosilanes with reported pKa values. We show that ring strain significantly contributes to this unusual acidity along with inductive and electrostatic effects. The conjugate base, TSMPSi, activates a THF molecule in the presence of CH‐acids to generate a highly fluxional alkoxysilane via trace amounts of [TSMPSiH]+ functioning as a strain‐release Lewis acid. This reaction involves a formal oxidation‐state change from SiII to SiIV, presenting intriguing similarities with transition‐metal‐mediated processes.
Efficient and Selective Interplay Revealed: CO2 Reduction to CO over ZrO2 by Light with Further Reduction to Methane over Ni0 by Heat Converted from Light
Authors: Zhang Hongwei , Itoi Takaomi , Konishi Takehisa , Izumi Yasuo
Published: January 2021

The reaction mechanism of CO2 photoreduction into methane was elucidated by time‐course monitoring of the mass chromatogram, in situ FTIR spectroscopy, and in situ extended X‐ray absorption fine structure (EXAFS). Under 13CO2, H2, and UV/Vis light, 13CH4 was formed at a rate of 0.98 mmol h−1 gcat−1 using Ni (10 wt %)‐ZrO2 that was effective at 96 kPa. Under UV/Vis light irradiation, the 13CO2 exchange reaction and FTIR identified physisorbed/chemisorbed bicarbonate and the reduction because of charge separation in/on ZrO2, followed by the transfer of formate and CO onto the Ni surface. EXAFS confirmed exclusive presence of Ni0 sites. Then, FTIR spectroscopy detected methyl species on Ni0, which was reversibly heated to 394 K owing to the heat converted from light. With D2O and H2, the H/D ratio in the formed methane agreed with reactant H/D ratio. This study paves the way for using first row transition metals for solar fuel generation using only UV/Vis light.
Interplay between a Foldamer Helix and a Macrocycle in a Foldarotaxane Architecture
Authors: Gauthier Maxime , Koehler Victor , Clavel Caroline , Kauffmann Brice , Huc Ivan , Ferrand Yann , Coutrot Frédéric
Published: January 2021

The design and synthesis of a novel rotaxane/foldaxane hybrid architecture is reported. The winding of an aromatic oligoamide helix host around a dumbbell‐shaped thread‐like guest, or axle, already surrounded by a macrocycle was evidenced by NMR spectroscopy and X‐ray crystallography. The process proved to depend on the position of the macrocycle along the axle and the associated steric hindrance. The macrocycle thus behaves as a switchable shield that modulates the affinity of the helix for the axle. Reciprocally, the foldamer helix acts as a supramolecular auxiliary that compartmentalizes the axle. In some cases, the macrocycle is forced to move along the axle to allow the foldamer to reach its best recognition site.
30th Anniversary of comprehensive two‐dimensional gas chromatography: Latest advances
Authors: Zanella Delphine , Focant Jean‐François , Franchina Flavio A.
Published: January 2021

In this review, we report on the latest (2020‐Early 2021) instrumental advances and applications of comprehensive two‐dimensional gas chromatography (GC×GC), including its hyphenation with novel upstream or downstream processes (sample preparation approaches or detection technologies). We also discuss software and analysis workflow developments necessary to elaborate the dense chemical information obtained. Thirty years after its inception, the use of GC×GC, as the main analytical tool or as a complementary platform, is undoubtedly shifting toward more applied challenges in a vast breadth of applications. Therefore, we consider the major fields (energy, fuel, foodstuff, plant, biological, and environmental) in which GC×GC has been successfully used, discussing some of the recent innovative research works.
A review of retention mechanism studies for packed column supercritical fluid chromatography
Authors: Si‐Hung Le , Bamba Takeshi
Published: January 2021

The packed column supercritical fluid chromatography has risen as a promising alternative separation technique to the conventional liquid chromatography and gas chromatography. Although the packed column supercritical fluid chromatography has many advantages compared to other chromatographic techniques, its separation mechanism is not fully understood due to the complex combination effects of many chromatographic parameters on separation quality and the lacking of global strategies for studying separation mechanisms. This review aims to provide recent information regarding the chromatographic behaviors and the effects of the parameters on the separation, discuss the results, and point out the remaining bottlenecks in the packed column supercritical fluid chromatography retention mechanism studies.
Sulfonamide functionalized amino acid‐based pH‐ and temperature‐sensitive biodegradable injectable hydrogels: Synthesis, physicochemical characterization and in vivo degradation kinetics
Authors: Le Thai Minh Duy , Nguyen Vu Viet Linh , Trinh Thuy An , Pham Ngoc Sinh , Lee Doo Sung , Huynh Dai Phu
Published: January 2021

In this research, a novel pH and temperature‐sensitive biodegradable oligomer serin‐b‐poly(lactide)‐b‐poly (ethylene glycol)‐b‐poly(lactide)‐b‐ oligomer serin (OS‐PLA–PEG–PLA‐OS) pentablock copolymer was synthesized with modification of serine to sulfonamide group. The properties of the different pentablock copolymer structures were detail characterized. The copolymer solution easily flowed at high pH and changed to gel state at physiological conditions (37°C, pH 7.4). The sol to gel behavior of these block copolymer solutions were controllable by tuning the length of PEG segment, PLA/PEG block ratio, the molecular weight and the concentration of the pentablock copolymer. The in vivo gelation of the copolymer solution was investigated. The stable gel was formed after injection into the back of the adult male Mus musculus Swiss Albino mice. The degradation process was observed after 6 weeks and showed that the hydrogel depot was bioresorbable without any detection of inflammation sign. The results in this study suggest that the OS‐PLA–PEG–PLA‐OS pentablock copolymer has the potential application as an injectable delivery vehicle for therapeutic drugs that easily denatured at low‐pH condition.
Buzzing with possibilities: Training and olfactory generalization in conservation detection dogs for an endangered stonefly species
Authors: Rutter Nicholas J. , Mynott Julia H. , Howell Tiffani J. , Stukas Arthur A. , Pascoe Jack H. , Bennett Pauleen C. , Murphy Nicholas P.
Published: January 2021

Professionally trained conservation detection dogs (CDDs) are taught to locate biological targets, including cryptic and low‐density plant and animal species, but have been largely underused in detecting endangered invertebrates.

This pilot study assessed the ability of four volunteer CDD/handler teams to detect the endangered Alpine stonefly (Eustheniidae: Thaumatoperla alpina). Once trained, all teams identified 100% of the targets when present in container line‐up searches, with no false alerts.

In the field, all available dog–handler teams (n = 3) alerted to the presence of numerous T. alpina individuals, including individuals that were not seen by experienced visual surveyors.

Three of the four CDDs also spontaneously alerted (i.e. exhibited olfactory generalization) to a closely related species, the Stirling stonefly (Thaumatoperla flaveola), in an initial container search.

These preliminary results demonstrate that volunteer dog–handler teams can be trained to detect T. alpina in situ. In addition, CDDs may be able to perform olfactory generalization effectively: from detecting a commonly occurring species to detecting a closely related, rare, or cryptic species.
Red and risk preferences: The effects of culture and individual differences
Authors: Jiang Feng , Zhang Rui , Lu Su
Published: January 2021

Color is shown to affect decision making and judgment. However, no prior research has examined both between‐ and within‐culture variations in color associations. To this end, we test the red (vs. green) effects on risk preferences in the United States and China while assessing individual differences in color associations. Across three studies, we find cultural reactance effects, that is, in the domain of risk aversion, the color associated with gain (American: green/Chinese: red) leads participants to become more risk averse when they personally associate green (in America) and red (in China) with loss. In the domain of risk seeking, the color associated with loss (American: red/Chinese: green) leads participants to become more risk seeking when they personally associate green (in China) and red (in America) with gain. By providing a novel perspective that integrates between‐ and within‐culture variations, our findings have implications for understanding the generalizability of the color effects across individuals and cultures.
LC–MS‐based plasma metabolomics study of the intervention effect of different polar parts of hawthorn on gastrointestinal motility disorder rats
Authors: Wang Kaiyang , Luo Lan , Xu Xiaoli , Chen Xingyu , He Qiong , Zou Zhongjie , Wang Shumei , Liang Shengwang
Published: January 2021

Dyspepsia, one of the most prevalent diseases of the digestive tract that impacts the quality of patient life, is mainly caused by gastrointestinal motility disorder. Hawthorn is a commonly used traditional Chinese medicine for treating dyspepsia, and has been proven to improve gastrointestinal motility. Herein, a rat model of gastrointestinal motility disorder was established by subcutaneous injection with atropine. The modeled rats were treated with four polar parts (T1–4 in descending polarity, corresponding to water,n‐butanol, ethyl acetate and petroleum ether extracts, respectively) of hawthorn. Through metabolomics analysis, a total of 20 significantly metabolites were identified with significant changes in their abundance levels and these metabolites were related to many metabolic pathways such as amino acid metabolism and primary bile acid biosynthesis. The results showed that T3 had the best therapeutic effect of promoting gastrointestinal motility. Other parts showed no obvious therapeutic effect, demonstrating that the effective components of hawthorn may be compounds of medium polarity. T3 might achieve good therapeutic effects owing to the gastrointestinal motility promotion activity, and by rectifying the disturbed metabolic pathways in the gastrointestinal motility disorder model.
Diphlorethohydroxycarmalol inhibits melanogenesis via protein kinase A/cAMP response element‐binding protein and extracellular signal‐regulated kinase‐mediated microphthalmia‐associated transcription factor downregulation in α‐melanocyte stimulating hormone‐stimulated B16F10 melanoma cells and zebrafish
Authors: Ding Yuling , Jiang Yunfei , Im Seung Tae , Myung Seungwon , Kim Hyun‐Soo , Lee Seung‐Hong
Published: January 2021

Diphlorethohydroxycarmalol (DPHC) is a marine polyphenolic compound derived from brown alga Ishige okamurae. A previously study has suggested that DPHC possesses strong mushroom tyrosinase inhibitory activity. However, the anti‐melanogenesis effect of DPHC has not been reported at cellular level. The objective of the present study was to clarify the melanogenesis inhibitory effect of DPHC and its molecular mechanisms in murine melanoma cells (B16F10) and zebrafish model. DPHC significantly inhibited tyrosinase activity and melanin content dose‐dependently in α‐melanocyte stimulating hormone (α‐MSH)‐stimulated B16F10 cells. This polyphenolic compound also suppressed the expression of phosphorylation of cAMP response element‐binding protein (CREB) by attenuating phosphorylation of cAMP‐dependent protein kinase A, resulting in decreased MITF expression levels. Furthermore, DPHC downregulated MITF protein expression levels by promoting the phosphorylation of extracellular signal‐regulated kinase. It also inhibited tyrosinase, tyrosinase‐related protein 1 (TRP‐1), and TRP‐2 in α‐MSH stimulated B16F10 cells. In in vivo studies using zebrafish, DPHC also markedly inhibited melanin synthesis in a dose‐dependent manner. These results demonstrate that DPHC can effectively inhibit melanogenesis in melanoma cells in vitro and in zebrafish in vivo, suggesting that DPHC could be applied in fields of pharmaceutical and cosmeceuticals as a skin‐whitening agent.

Significance of study: The present study showed for the first time that DPHC could inhibit a‐MSH‐stimulated melanogenesis via PKA/CREB and ERK pathway in melanoma cells. It also could inhibit pigmentation in vivo in a zebrafish model. This evidence suggests that DPHC has potential as a skin whitening agent. Taken together, DPHC could be considered as a novel anti‐melanogenic agent to be applied in cosmetic, food, and medical industry.
Emergent mechanical thrombectomy for right atrial clot and massive pulmonary embolism using flowtriever
Authors: Bayona Molano Maria del Pilar , Salsamendi Jason , Mani Naganathan
Published: January 2021

This case demonstrated a feasible alternative to treat "clot in transit" associated with pulmonary embolism using FlowTriever Inari device. The pre‐existing approved AngioVac device requires extracorporeal circulation support and more invasiveness. FlowTriever permits mechanical thrombectomy with versatile approach without additional extracorporeal perfusion setting. Additional studies are required to reach a definitive conclusion.
Contained hypopharyngeal and cervical esophageal perforation masquerading as retropharyngeal abscess
Authors: Klug Theodore D. , Shires Courtney B.
Published: January 2021

It is possible to have a spontaneous hypopharyngeal and cervical esophageal perforation following yelling. We believe our case is the first study showing such an event, which can become catastrophic if not addressed in a timely manner.
Dendrite‐free lithium and sodium metal anodes with deep plating/stripping properties for lithium and sodium batteries
Authors: Wang Jianyi , Kang Qi , Yuan Jingchao , Fu Qianru , Chen Chunhua , Zhai Zibo , Liu Yang , Yan Wei , Li Aijun , Zhang Jiujun
Published: January 2021

Although lithium (Li) and sodium (Na) metals can be selected as the promising anode materials for next‐generation rechargeable batteries of high energy density, their practical applications are greatly restricted by the uncontrollable dendrite growth. Herein, a platinum (Pt)–copper (Cu) alloy‐coated Cu foam (Pt–Cu foam) is prepared and then used as the substrate for Li and Na metal anodes. Owing to the ultrarough morphology with a three‐dimensional porous structure and the quite large surface area as well as lithiophilicity and sodiophilicity, both Li and Na dendrite growths are significantly suppressed on the substrate. Moreover, during Li plating, the lithiated Pt atoms can dissolve into Li phase, leaving a lot of microsized holes on the substrate. During Na plating, although the sodiated Pt atoms cannot dissolve into Na phase, the sodiation of Pt atoms elevates many microsized blocks above the current collector. Either the holes or the voids on the surface of Pt–Cu foam what can be extra place for deposited alkali metal, what effectively relaxes the internal stress caused by the volume exchange during Li and Na plating/stripping. Therefore, the symmetric batteries of Li@Pt–Cu foam and Na@Pt–Cu foam have both achieved long‐term cycling stability even at ultrahigh areal capacity at 20 mAh cm−2.
Hydrodechlorination of Dichloromethane by a Metal‐Free Triazole‐Porphyrin Electrocatalyst: Demonstration of Main‐Group Element Electrocatalysis**
Authors: Williams Caroline K. , Lashgari Amir , Devi Nilakshi , Ang Marcus , Chaturvedi Ashwin , Dhungana Pranita , Jiang Jianbing Jimmy
Published: January 2021

In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element‐based molecular triazole‐porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70 % and current density of −13 mA cm−2 at a potential of −2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms.
Dynamic Covalent Properties of a Novel Indolo[3,2‐b]carbazole Diradical
Authors: Badía‐Domínguez Irene , Peña‐Álvarez Miriam , Wang Deliang , Pérez Guardiola Andrés , Vida Yolanda , Rodríguez González Sandra , López Navarrete Juan T. , Hernández Jolín Víctor , Sancho García Juan C. , García Baonza Valentín , Nash Rosie , Hartl František , Li Hongxiang , Ruiz Delgado M. Carmen
Published: January 2021

This work describes the synthesis and properties of a dicyanomethylene‐substituted indolo[3,2‐b]carbazole diradical ICz‐CN. This quinoidal system dimerises almost completely to (ICz‐CN)2, which contains two long C(sp3)−C(sp3) σ‐bonds between the dicyanomethylene units. The minor open‐shell ICz‐CN component in the solid‐state mixture was identified by EPR spectroscopy. Cyclic voltammetry and UV–visible spectroelectrochemical data, as well as comparison with reference monomer ICz‐Br reveal that the nature of the one‐electron oxidation of (ICz‐CN)2 at ambient temperature and ICz‐CN at elevated temperature is very similar in all these compounds due to the prevailing localization of their HOMO on the ICz backbone. The peculiar cathodic behaviour reflects the co‐existence of (ICz‐CN)2 and ICz‐CN. The involvement of the dicyanomethylene groups stabilizes the close‐lying LUMO and LUMO+1 of (ICz‐CN)2 and especially ICz‐CN compared to ICz‐Br, resulting in a distinctive cathodic response at low overpotentials. Differently from neutral ICz‐CN, its radical anion and dianion are remarkably stable under ambient conditions. The UV/Vis(–NIR) electronic transitions in parent (ICz‐CN)2 and ICz‐CN and their different redox forms have been assigned convincingly with the aid of TD‐DFT calculations. The σ‐bond in neutral (ICz‐CN)2 is cleaved in solution and in the solid‐state upon soft external stimuli (temperature, pressure), showing a strong chromism from light yellow to blue–green. Notably, in the solid state, the monomeric diradical species is predominantly formed under high hydrostatic pressure (>1 GPa).
Reactions of Late First‐Row Transition Metal (Fe‐Zn) Dichlorides with a PGeP Pincer Germylene
Authors: Arauzo Ana , Cabeza Javier A. , Fernández Israel , García‐Álvarez Pablo , García‐Rubio Inés , Laglera‐Gándara Carlos J.
Published: January 2021

The reactivity of the PGeP germylene 2,2’‐bis(di‐isopropylphosphanylmethyl)‐5,5’‐dimethyldipyrromethane‐1,1’‐diylgermanium(II), Ge(pyrmPiPr2)2CMe2, with late first‐row transition metal (Fe‐Zn) dichlorides has been investigated. All reactions led to PGeP pincer chloridogermyl complexes. The reactions with FeCl2 and CoCl2 afforded paramagnetic square planar complexes of formula [MCl{κ3P,Ge,P‐GeCl(pyrmPiPr2)2CMe2}] (M=Fe, Co). While the iron complex maintained an intermediate spin state (S1; μeff=3.0 μB) over the temperature range 50–380 K, the effective magnetic moment of the cobalt complex varied linearly with temperature from 1.9 μB at 10 K to 3.6 μB at 380 K, indicating a spin crossover behavior that involves S1/2 (predominant at T<180 K) and S3/2 (predominant at T>200 K) species. Both cobalt(II) species were detected by electron paramagnetic resonance at T<20 K. The reaction of Ge(pyrmPiPr2)2CMe2 with [NiCl2(dme)] (dme=dimethoxyethane) gave a square planar nickel(II) complex, [NiCl{κ3P,Ge,P‐GeCl(pyrmPiPr2)2CMe2}], whereas the reaction with CuCl2 involved a redox process that rendered a mixture of the germanium(IV) compound GeCl2(pyrmPiPr2)2CMe2 and a binuclear copper(I) complex, [Cu2{μ‐κ3P,Ge,P‐GeCl(pyrmPiPr2)2CMe2}2], whose metal atoms are in tetrahedral environments. The reaction of the germylene with ZnCl2 led to the tetrahedral derivative [ZnCl{κ3P,Ge,P‐GeCl(pyrmPiPr2)2CMe2}].
A Mild, General, Metal‐Free Method for Desulfurization of Thiols and Disulfides Induced by Visible‐Light
Authors: Qiu Wenting , Shi Shuai , Li Ruining , Lin Xianfeng , Rao Liangming , Sun Zhankui
Published: January 2021

Main observation and conclusion

A visible‐light‐induced metal‐free desulfurization method for thiols and disulfides has been explored. This radical desulfurization features mild conditions, robustness, and excellent functionality compatibility. It was successfully applied not only to the desulfurization of small molecules, but also to peptides.
Optogenetic Control of Phosphatidylinositol (3,4,5)‐Triphosphate Production by Light‐Sensitive Cryptochrome Proteins on the Plasma Membrane
Authors: Yang Lingzhi , Ozawa Takeaki , Dong Haifeng , Zhang Xueji
Published: January 2021

Main observation and conclusion

Phosphatidylinositol (3,4,5)‐triphosphate (PIP3), acting as a fundamental second messenger, is emerging as a promising biomarker for disease diagnosis and prognosis. However, the real time analysis of phosphoinositide in living cells remains a key challenge owing to the low basal abundance and its fast metabolic rate. Herein, we design an optogenetic system that uses light sensitive protein‐protein interaction between Arabidopsis cryptochrome 2 (CRY2) and CIB1 to spatiotemporally visualize the PIP3 production with sub‐second timescale. In this system, a CIBN is anchored on the plasma membrane, whereas a CRY2 fused with a constitutively active PI3‐kinase (acPI3K) would be driven from the cytosol to the membrane by the blue‐light‐activated CRY2‐CIB1 interaction upon light irradiation. The PIP3 production is visualized via a fused fluorescent protein by the translocation of a Pleckstrin Homology (PH) domain (GRP1) from the cytosol to the plasma membrane with high specificity. We demonstrated the fast dynamics and reversibility of the optogenetic system initiated PIP3 synthesis on the plasma membrane. Notably, the real‐time cell movements were also observed upon localized light stimulation. The established optogenetic method provides a novel spatiotemporal strategy for specific PIP3 visualization, which is beneficial to improve the understanding of PIP3 functions.
Recent Advances in Pt‐Based Ultrathin Nanowires: Synthesis and Electrocatalytic Applications†
Authors: Wang Yu , Yuan Yuliang , Huang Hongwen
Published: January 2021

Electrochemical energy conversion devices, with typical examples of fuel cells, are the centers in building a sustainable energy system that avoids environmental pollution and lowers the dependence on fossil fuels. Platinum (Pt)‐based catalysts are among the most potential candidates to drive these reactions due to their superior catalytic performance. Among the various Pt‐based catalysts, Pt‐based ultrathin nanowires exhibit remarkable catalytic performance due to the unique structural merits (i.e., high Pt atom utilization and strong interaction with supports). In this review, we attempt to summarize the recent advances in the synthesis of Pt‐based ultrathin nanowires, as well as their applications in various kinds of electrocatalytic reactions. We conclude this review with an emphasis on the current challenges in terms of synthesis and applications of Pt‐based ultrathin nanowires. Perspectives on further development are also proposed, which is expected to guide the related research in the future.
Quantum approach for nanoparticle fluorescence by sub‐ns photon detection
Authors: Yamamoto Masanobu , Robinson J. Paul
Published: January 2021

Well defined detection and analysis of nanoparticle‐sized samples such as extracellular vesicles or viruses may be important for potential disease diagnostics. However, using conventional flow‐cytometry optical methods to evaluate such small particles is quite challenging. The reason is that the particle is smaller than the diffraction limit, making detection difficult. An alternative approach is fluorescence detection via conjugated fluorochromes attached to the nanoparticles; the challenge in this case is the limitation imposed upon detection of a very small number of emitted photons buried in high background photon counts. Emitted fluorescence is described by the well‐known equation kf = σa I Q, which describes the emitted fluorescence rate (kf) (photons/s) as the multiplication of molecular absorption cross section(σa), excitation intensity (I), and quantum yield (Q). In addition, the excitation rate is equal to 1/t, which is the inverse of the lifetime of several ns representing the most typical conjugated fluorescent molecules used in flow cytometry. We recently developed a sub‐ns photon sensor that is faster than most fluorescence lifetimes, since sub‐ns speed is a critically important parameter for the separation of individual emitted photons. Based on our observation of fluorescence and background levels on typical commercial flow cytometers it is evident that a significant component of the background is induced by water‐molecular vibrations. Therefore, understanding what constitutes all the components that contribute to the signals we measure in flow cytometry would help in defining what we currently call “background signals.” We attempted to define a theoretical model to try to unravel these issues. This model was based on use of a reflective dry surface in the absence of water molecules. Our objective was to determine if it is possible to minimize background and enhance signal, and to provide valuable information on the contributing components of the signals collected. In order to test this model, we tested a single dried particle 50 nm in diameter on a reflective surface with minimum background. While this is clearly not a standard biological system, our results suggest that this quantum approach closely follows established photon base theory. Our goal was to define the parameters for practical nanoparticle‐fluorescence analysis while enhancing our knowledge of the contribution of background properties.
Program helps adults with learning disabilities develop core skills for life
Authors: Bannister Mary
Published: January 2021

Program Manager Brad Baranowski and Associate Dean Pilar Lopez of the Occupational & Life Skills program at Bellevue College explained how the program achieves its goal of helping students develop self‐awareness, self‐advocacy, and self‐determination.
Prognostic value of impaired hepato‐renal function and liver fibrosis in patients admitted for acute heart failure
Authors: Kawahira Masatsugu , Tamaki Shunsuke , Yamada Takahisa , Watanabe Tetsuya , Morita Takashi , Furukawa Yoshio , Kawasaki Masato , Kikuchi Atsushi , Kawai Tsutomu , Seo Masahiro , Nakamura Jun , Kayama Kiyomi , Kimura Takanari , Ueda Kunpei , Sakamoto Daisuke , Kogame Takehiro , Ito Shota , Chang Yongchol , Fukunami Masatake
Published: January 2021

Aims

Cardiohepatic interactions have been a focus of attention in heart failure (HF). The model for end‐stage liver disease excluding international normalized ratio (MELD‐XI) score has been shown to be useful for predicting poor outcomes in patients with acute decompensated HF (ADHF). Furthermore, the fibrosis‐4 (FIB‐4) index, a simple marker to assess liver fibrosis, predicts adverse prognoses in patients with HF as well. However, there is little information available on the prognostic significance of the combination of the MELD‐XI score and FIB‐4 index in patients with ADHF and its association with left ventricular ejection fraction (LVEF) subgroup.

Methods and results

We prospectively studied 466 consecutive patients who were admitted for ADHF [HF with reduced LVEF (LVEF < 40%): n = 164, HF with mid‐range LVEF (40% ≤ LVEF < 50%): n = 104, and HF with preserved LVEF (LVEF ≥ 50%): n = 198]. We calculated the MELD‐XI score and FIB‐4 indices at discharge. The primary endpoint was all‐cause death (ACD). During the mean follow‐up period of 2.8 years, 143 patients had ACD. In the multivariate Cox analysis, the MELD‐XI score and FIB‐4 index were independently associated with ACD. Patients were stratified into the following three groups according to the median value of MELD‐XI score (=11) and FIB‐4 index (=2.13): Group 1 had both a low MELD‐XI score and a low FIB‐4 index; Group 2 had either a high MELD‐XI score (MELD‐XI score ≥11) or a high FIB‐4 index (FIB‐4 index ≥2.13); and Group 3 had both a high MELD‐XI score and a high FIB‐4 index. Kaplan–Meier analysis revealed that Group 2 and Group 3 had a significantly greater risk of ACD than Group 1 [Group 2 vs. Group 1: adjusted hazard ratio, 2.48 (95% confidence interval: 1.75–3.53), P < 0.0001; Group 3 vs. Group 1: adjusted hazard ratio, 7.03 (95% confidence interval: 3.95–13.7), P < 0.0001]. In addition, the patients with both a higher MELD‐XI score and FIB‐4 index showed a significantly higher risk of ACD also in the patients with HF with reduced LVEF, HF with mid‐range LVEF, and HF with preserved LVEF (all P < 0.0001).

Conclusions

The combination of MELD‐XI score and FIB‐4 index may be useful for stratifying patients at risk for ACD in patients with ADHF, irrespective of LVEF.
Sulfonium Salts Enable the Direct Sulfenylation of Activated C(sp3)−H Bonds
Authors: Zhang Liang , Nagaraju Sakkani , Paplal Banoth , Lin Yunliang , Liu Shuhua
Published: January 2021

Herein, the direct α‐sulfenylation of a series of β‐dicarbonyl, β‐ketophosphonate, and β‐ketonitrile compounds, mediated by sulfonium salts has been described. Traditionally, sulfonium salts which are synthesized by activation of dialkylsulfoxides serve as oxidizing agents or precursors of sulfur ylide. In this transformation, sulfonium salts as readily prepared and operationally simple sulfenylation reagents firstly achieved alkylsulfenylation of various activated C(sp3)−H bonds with the formation of tetra‐substituted carbon center.
Synthesis of γ‐Spirolactams by Birch Reduction of Arenes
Authors: Krüger Tobias , Linker Torsten
Published: January 2021

A convenient method for the synthesis of γ‐spirolactams in only three steps is described. Birch reduction of inexpensive and commercially available aromatic carboxylic acids in the presence of chloroacetonitrile affords nitriles in moderate to good yields. Suitable precursors are methyl‐substituted benzoic acids, naphthoic, and anthroic acid. Subsequent catalytic hydrogenation proceeds smoothly with PtO2 or Raney Ni as catalysts and lactams are isolated in excellent yields and stereoselectivities. Thus, up to 3 new stereogenic centers can be constructed as sole diastereomers from achiral benzoic acids. Furthermore, it is possible to control the degree of saturation at different pressures, affording products with 0, 1, or 2 double bonds. Overall, more than 15 new γ‐spirolactams have been synthesized in analytically pure form.
Testing the viability of measuring intraocular pressure using soundwaves from a smartphone
Authors: Soanes Matthew , Essa Khamis , Butt Haider
Published: January 2021

Early detection of increasing values of intraocular pressure (IOP) due to glaucoma can prevent severe ocular diseases and ultimately, prevent loss of vision. Currently, the need for an accurate, mobile measurement of IOP that shows no correlation to central corneal thickness is unmet within the modern healthcare practices. There is a potential to utilize soundwaves as a mobile measurement method and therefore, the relationship between IOP and the reflection coefficient of sound waves is investigated. Simulations are conducted using COMSOL Multiphysics to provide theoretical confirmation of the worthiness of the experiment. An experiment is conducted to further investigate the relationship between the internal pressure of an object and its acoustic reflection coefficient. The experiment exploits the use of hydrostatic pressure to determine internal pressure, and the reflection coefficient is measured and analyzed. An initial experiment is conducted to identify the resonant frequency of the object and the optimal frequency for maximizing reflection. The experiment shows comprehensively that there is a relationship between the internal pressure of an object and its acoustic reflection coefficient, providing a confirmation of the theory that would allow mobile measurements of IOP to be conducted with the use of a smart phone.
Brucea Javanica: A novel nonedible feedstock for bio‐based lubricant application with the effect of ZrO2 nanoparticles
Authors: Singh Yashvir , Singh Nishant Kumar , Sharma Abhishek , Lila Manish Kumar , Singla Amneesh , Chinnasamy Vivekanandhan
Published: January 2021

The rise in demand for energy and pollution of the environment from the usage of petroleum products promote research to explore environmentally friendly substitutes. Brucea Javanica oil has the potential to be a mineral oil and is plentiful and cheap in India. In this research work, the oil was epoxidized to focus on improving the oxidation stability of the Brucea Javanica oil. In addition, ZrO2 nanoparticles are introduced to the chemically modified Brucea Javanica oil in a particular proportion and tested for tribological behavior. The epoxidation process provided better lubricating properties due to an increase in viscosity, flash point, and pour point. During the assessment, 0.5% consisting of ZrO2 nanoparticles resulted in significant reductions in coefficient of friction and rate of wear. Worn surfaces were analyzed using scanning electron microscope and they exhibit excellent surfaces when nanoparticles were introduced up to 0.5% concentration due to improved lubricant film formation on metal surfaces. The optimal level of inclusion to the epoxidized Brucea Javanica oil was discovered at a concentration of 0.5%, and an increase after this limit results in maximum wear of the surfaces due to their agglomeration on the surface. So, nanoparticles up to a certain limit are useful for reducing the friction and wear of the surfaces.
Effect of superstructure modeling assumptions on the seismic performance of seismically isolated buildings
Authors: Kitayama Shoma , Constantinou Michael C.
Published: January 2021

Recent studies on the seismic performance of seismically isolated buildings with braced frames designed using the minimum criteria of the ASCE 7‐16 standard resulted in observations that seismically isolated buildings have unacceptable collapse performance due to either insufficient isolator displacement capacity or excessive inelastic structural deformations. The collapse performance and the overall performance could be improved by increasing the displacement capacity of the isolators and by limiting inelastic action in the superstructure while still providing ductile detailing. These observations may have been dependent on the modeling assumptions for the superstructure. This article investigates the effect of various modeling methods that are commonly used in research and design practice on the seismic performance of a six‐story braced seismically isolated building with two different isolation systems, and a comparable nonisolated six‐story building, all designed to meet the minimum criteria of ASCE 7‐16. Performance measures considered in this study include story drift ratios, residual story drift ratios, floor accelerations, isolator horizontal displacement, and collapse. The study found that for seismically isolated buildings and for the modeling assumptions considered, only the inclusion of the effect of gravity frames has a beneficial effect of reducing the occurrence of small to moderate peak floor accelerations while there is insignificant effect on the other performance measures and particularly the computed probabilities of collapse in the MCER. Also, the different modeling assumptions were found to have a more important effect on the seismic performance of nonisolated buildings than that of comparable seismically isolated buildings.