bluuebunny/crossref_metadata_2025_split huggingface dataset:
NIR‐II Hydrogen‐Bonded Organic Frameworks (HOFs) Used for Target‐Specific Amyloid‐β Photooxygenation in an Alzheimer's Disease Model
Authors: Zhang Haochen , Yu Dongqin , Liu Shuting , Liu Chun , Liu Zhenqi , Ren Jinsong , Qu Xiaogang 
Published: November 2021

AbstractPhototherapy has emerged as a powerful approach for interrupting β‐amyloid (Aβ) self‐assembly. However, deeper tissue penetration and safer photosensitizers are urgent to be exploited for avoiding damaging nearby normal tissues and improving therapeutic effectiveness. A hydrogen‐bonded organic framework (HOF)‐based NIR‐II photooxygenation catalyst is presented here to settle the abovementioned challenges. By encapsulating the pyridinium hemicyanine dye DSM with a large two‐photon absorption (TPA) cross‐section in NIR‐II window into the porphyrin‐based HOF, the resultant DSM@n‐HOF‐6 exhibits significant two‐photon NIR‐II‐excited Fluorescence Resonance Energy Transfer (FRET) to generate singlet oxygen (1O2) for Aβ oxidation. Further, the target peptides of KLVFFAED (KD8) are covalently grafted on DSM@n‐HOF‐6 to enhance the blood–brain barrier (BBB) permeability and Aβ selectivity. The HOF‐based photooxygenation catalyst shows an outstanding inhibitory effect of Aβ aggregation upon the NIR‐II irradiation. Further in vivo studies demonstrate the obvious decrease of craniocerebral Aβ plaques and recovery of memory deficits in triple‐transgenic AD (3×Tg‐AD) model mice.
Solar Urea: Towards a Sustainable Fertilizer Industry
Authors: Xia Meikun , Mao Chengliang , Gu Alan , Tountas Athanasios A. , Qiu Chenyue , Wood Thomas E. , Li Young Feng , Ulmer Ulrich , Xu Yangfan , Viasus Camilo J. , Ye Jessica , Qian Chenxi , Ozin Geoffrey 
Published: November 2021

AbstractUrea, an agricultural fertilizer, nourishes humanity. The century‐old Bosch–Meiser process provides the world's urea. It is multi‐step, consumes enormous amounts of non‐renewable energy, and has a large CO2 footprint. Thus, developing an eco‐friendly synthesis for urea is a priority. Herein we report a single‐step Pd/LTA‐3A catalyzed synthesis of urea from CO2 and NH3 under ambient conditions powered solely by solar energy. Pd nanoparticles serve the dual function of catalyzing the dissociation of NH3 and providing the photothermal driving force for urea formation, while the absorption capacity of LTA‐3A removes by‐product H2O to shift the equilibrium towards urea production. The solar urea conversion rate from NH3 and CO2 is 87 μmol g−1 h−1. This advance represents a first step towards the use of solar energy in urea production. It provides insights into green fertilizer production, and inspires the vision of sustainable, modular plants for distributed production of urea on farms.
Enantioselective Allenation of Terminal Alkynes Catalyzed by Copper Halides of Mixed Oxidation States and Its Application to the Total Synthesis of Scorodonin
Authors: Wu Guolin , Yao Yuan , Li Gen , Zhang Xue , Qian Hui , Ma Shengming 
Published: November 2021

AbstractNaturally occurring conjugated allenynes are of general interest owing to their potent and various biological activities. The 1,5‐H transfer of alka‐1,4‐diyn‐3‐yl amines would be one of the most straightforward yet challenging approaches to such compounds since, in principle, two regioisomers may be formed involving two C−C triple bonds. Herein, a catalytic recipe of copper halides with mixed oxidation states, i.e., CuCl/CuBr2, has been identified to address the issues of the side reaction of conjugate addition and the selectivity of 1,5‐H transfer of alka‐1,4‐diyn‐3‐yl amines in EATA (enantioselective allenation of terminal alkynes) reaction involving 2‐alkynals. This method provided various allenynes with excellent enantioselectivities, and was also applied to the first highly enantioselective total synthesis of natural product scorodonin. Mechanistic studies and DFT calculations elucidated the regioselectivity for the observed 1,5‐H transfer.
Visible‐Light‐Induced C4‐Selective Functionalization of Pyridinium Salts with Cyclopropanols
Authors: Vellakkaran Mari , Kim Taehwan , Hong Sungwoo 
Published: November 2021

AbstractThe site‐selective C−H functionalization of heteroarenes is of considerable importance for streamlining the rapid modification of bioactive molecules. Herein, we report a general strategy for visible‐light‐induced β‐carbonyl alkylation at the C4 position of pyridines with high site selectivity using various cyclopropanols and N‐amidopyridinium salts. In this process, hydrogen‐atom transfer between the generated sulfonamidyl radicals and O−H bonds of cyclopropanols generates β‐carbonyl radicals, providing efficient access to synthetically valuable β‐pyridylated (aryl)ketones, aldehydes, and esters with broad functional‐group tolerance. In addition, the mild method serves as an effective tool for the site‐selective late‐stage functionalization of complex and medicinally relevant molecules.
Fluorinated bis(arylimino)‐6,7‐dihydro‐5H‐quinoline‐cobalt polymerization catalysts: Electronic versus steric modulation in the formation of vinyl‐terminated linear PE waxes
Authors: Zuo Zheng , Han Mingyang , Ma Yanping , Solan Gregory A. , Hu Xinquan , Liang Tongling , Sun Wen‐Hua 
Published: November 2021

AbstractCondensation of 2‐benzoyl‐6,7‐dihydro‐5H‐quinolin‐8‐one with an excess of the respective fluorinated aniline in the presence of cobalt (II) chloride has provided an effective one‐flask synthesis of the 2‐(phenyl(arylimino)methyl)‐8‐arylimino‐6,7‐dihydro‐5H‐quinoline‐cobalt (II) chloride complexes, [2‐(ArN=CPh)‐8‐(NAr)‐C9H9N]CoCl2 (Ar = 2‐Me‐4,6‐(CH(p‐FC6H4)2)2C6H2 Co1, 2,6‐Me2‐4‐(CH(p‐FC6H4)2)C6H2 Co2, 2,4‐Me2‐6‐(CH(p‐FC6H4)2)C6H2 Co3, 2‐Et‐4,6‐(CH(p‐FC6H4)2)2C6H2 Co4, 2‐i‐Pr‐4,6‐(CH(p‐FC6H4)2)2C6H2 Co5, 2‐F‐4,6‐(CH(p‐FC6H4)2)2C6H2 Co6). Structural characterization of Co2 and Co4 revealed the unsymmetrical nature of the N,N,N‐chelating ligands and the five‐coordinate geometries around the metal ions. Complexes Co1–Co6 all exhibited high activities as precatalysts for ethylene polymerization when treated with either MAO or MMAO producing highly linear (Tm′s > 118°C) low molecular weight polyethylene (Mw range: 0.69–31.51 kg mol−1) with a variety of dispersities (Mw/Mn range: 2.2–17.5). 2,6‐Dimethyl‐containing Co2 was the most productive precatalyst of the series reaching an exceptionally high activity of 27.06 × 106 g (PE) mol−1 (Co) h−1 at a temperature of 50°C. Additionally, ortho‐fluoride Co6 maintained an impressive level of activity at an operating temperature of 70°C and was able to maintain a long catalytic lifetime. Furthermore, the presence of vinyl end groups (–CH=CH2) in the 1H/13C NMR and IR spectra of their polymers supports the key role played by β‐H elimination in chain transfer.
The forgotten ocean: Why COP26 must call for vastly greater ambition and urgency to address ocean change
Authors: Laffoley Dan , Baxter John M. , Amon Diva J. , Claudet Joachim , Downs Craig A. , Earle Sylvia A. , Gjerde Kristina M. , Hall‐Spencer Jason M. , Koldewey Heather J. , Levin Lisa A. , Reid Chris P. , Roberts Callum M. , Sumaila Rashid U. , Taylor Michelle L. , Thiele Torsten , Woodall Lucy C. 
Published: November 2021

Abstract

Of all the interconnected threats facing the planet, the top two are the climate and the biodiversity crises. Neither problem will be solved if we ignore the ocean. To turn the tide in favour of humanity and a habitable planet, we need to recognize and better value the fundamental role that the ocean plays in the earth system, and prioritize the urgent action needed to heal and protect the ocean at the ‘Earthscape’ level – the planetary scale at which processes to support life operate.
The countries gathering at COP26 have unparalleled political capacity and leadership to make this happen. COP26 could be the turning point, but there must be commitment to united action for the ocean, as well as planning to meet those commitments, based on science‐led solutions that address the interconnectivity of the ocean, climate, and biodiversity.
Key ways in which the ocean both contributes to and acts as the major buffer for climate change are summarized, focusing on temperature, but not forgetting the role of storing carbon. It is noted with ‘high confidence’ that the ocean has stored 91% of the excess heat from global warming, with land, melting ice, and the atmosphere only taking up approximately 5, 3, and 1%, respectively.
We also highlight the impact of the recent large release of heat from the ocean to the atmosphere during the 2015–2016 El Niño. We then present six science‐based policy actions that form a recovery stimulus package for people, climate, nature, and the planet. Our proposals highlight what is needed to view, value, and treat the planet, including the ocean, for the benefit and future of all life.
The relationship between FR0 radio galaxies and gigahertz‐peaked spectrum sources
Authors: Mikhailov Alexander , Sotnikova Yulia 
Published: November 2021

AbstractWe present the results of our study of the relationship between Fanaroff‐Riley type 0 (FR0) radio galaxies and gigahertz‐peaked spectrum (GPS) sources. Quasi‐simultaneous radio spectra of 34 FR0s were obtained at 2.25–22.3 GHz with the radio telescope RATAN‐600 in 2020–2021 during 2–6 epochs. Most FR0s have flat radio spectra, but we found many spectra with a peaked shape. Due to this fact and the compact nature of FR0s, we suggest their possible relationship with compact steep‐spectrum (CSS)/GPS radio sources. We analyzed broadband radio spectra of the 34 FR0s using the RATAN‐600 measurements and available literature data. There are 14 FR0 objects which can be CSS/GPS radio source candidates. Most FR0s have broader radio spectra than those of genuine GPS sources, with like in blazars. Most spectral indices at the frequencies below and above the peak do not correspond to the values typical of canonical GPS sources. We classified 3 FR0s as low‐power GPS sources according to the canonical criteria. The key issue is the variability properties of FR0s. Some FR0s demonstrate a variability level of up to 25% on a time scale of 1 year according to the RATAN‐600 measurements. The flare phenomena in FR0 objects can imply a relationship between them and blazars.
Unveiling the Unique Roles of Metal Coordination and Modulator in the Polymorphism Control of Metal‐Organic Frameworks
Authors: Li Zi‐Jian , Ju Yu , Zhang Zeya , Lu Huangjie , Li Yongxin , Zhang Ningjin , Du Xian‐Long , Guo Xiaofeng , Zhang Zhi‐Hui , Qian Yuan , He Ming‐Yang , Wang Jian‐Qiang , Lin Jian 
Published: November 2021

AbstractPolymorphism control of metal‐organic frameworks is highly desired for elucidating structure‐property relationships, but remains an empirical process and is usually done in a trial‐and‐error approach. We adopted the rarely used actinide cation Th4+ and a ditopic linker to construct a series of thorium‐organic frameworks (TOFs) with a range of polymorphs. The extraordinary coordination versatility of Th4+ cations and clusters, coupled with synthetic modulation, gives five distinct phases, wherein the highest degree of interpenetration (threefold) and porosity (75.9 %) of TOFs have been achieved. Notably, the O atom on the capping site of the nine‐coordinated Th4+ cation can function as a bridging unit to interconnect neighboring secondary building units (SBUs), affording topologies that are undocumented for other tetravalent‐metal‐containing MOFs. Furthermore, for the first time HCOOH has been demonstrated as a bridging unit of SBUs to further induce structural complexity. The resulting TOFs exhibit considerably different adsorption behaviors toward organic dyes, thus suggesting that TOFs represent an exceptional and promising platform for structure‐property relationship study.
Low‐Valent Titanium Species Stabilized with Aluminum/Boron Hydride Fragments
Authors: del Horno Estefanía , Jover Jesús , Mena Miguel , Pérez‐Redondo Adrián , Yélamos Carlos 
Published: November 2021

AbstractLow‐valent titanium species were prepared by reaction of [TiCp*X3] (Cp*=η5‐C5Me5; X=Cl, Br, Me) with LiEH4 (E=Al, B) or BH3(thf), and their structures elucidated by experimental and theoretical methods. The treatment of trihalides [TiCp*X3] with LiAlH4 in ethereal solvents (L) leads to the hydride‐bridged heterometallic complexes [{TiCp*(μ‐H)}2{(μ‐H)2AlX(L)}2] (L=thf, X=Cl, Br; L=OEt2, X=Cl). Density functional theory (DFT) calculations for those compounds reveal an open‐shell singlet ground state with a Ti−Ti bond and can be described as titanium(II) species. The theoretical analyses also show strong interactions between the Ti−Ti bond and the empty s orbitals of the Al atom of the AlH2XL fragments, which behave as σ‐accepting (Z‐type) ligands. Analogous reactions of [TiCp*X3] with LiBH4 (2 and 3 equiv.) in tetrahydrofuran at room temperature and at 85 °C lead to the titanium(III) compounds [{TiCp*(BH4)(μ‐X)}2] (X=Cl, Br) and [{TiCp*(BH4)(μ‐BH4)}2], respectively. The treatment of [TiCp*Me3] with 4 and 5 equiv. of BH3(thf) produces the diamagnetic [{TiCp*(BH3Me)}2(μ‐B2H6)] and paramagnetic [{TiCp*(μ‐B2H6)}2] complexes, respectively.
Diastereoselective Alkene Hydroesterification Enabling the Synthesis of Chiral Fused Bicyclic Lactones
Authors: Shi Zhanglin , Shen Chaoren , Dong Kaiwu 
Published: November 2021

AbstractPalladium‐catalysed diastereoselective hydroesterification of alkenes assisted by the coordinative hydroxyl group in the substrate afforded a variety of chiral γ‐butyrolactones bearing two stereocenters. Employing the carbonylation‐lactonization products as the key intermediates, the route from the alkenes with single chiral center to chiral THF‐fused bicyclic γ‐lactones containing three stereocenters was developed.
Racemization mechanism of lithium tert‐butylphenylphosphido‐borane: A kinetic insight
Authors: Fortrie Rémy , Gatineau David , Hérault Damien , Béal Aurélie , Naubron Jean‐Valère , Giordano Laurent , Buono Gérard 
Published: November 2021

AbstractThe racemization mechanism of tert‐butylphenylphosphido‐borane is investigated experimentally and theoretically. Based on this converging approach, it is shown, first, that several phosphido‐borane molecular species coexist at the time of the reaction and, second, that one particular of both initially assumed reactive routes most significantly contribute to the overall racemization process. From our converging modeling and experimental measurement, it comes out that the most probable species to be here encountered is a phosphido‐borane‐Li (THF)2 neutral solvate, whose P‐stereogenic center monomolecular inversion through a Y‐shaped transition structure (ΔrG°≠: 81 kJ mol−1) brings the largest contribution to the racemization process.
Temperature and Composition Dependent Optical Properties of CdSe/CdS Dot/Rod‐Based Aerogel Networks
Authors: Rusch Pascal , Pluta Denis , Lübkemann Franziska , Dorfs Dirk , Zámbó Dániel , Bigall Nadja C. 
Published: November 2021

AbstractEmploying nanocrystals (NCs) as building blocks of porous aerogel network structures allows the conversion of NC materials into macroscopic solid structures while conserving their unique nanoscopic properties. Understanding the interplay of the network formation and its influence on these properties like size‐dependent emission is a key to apply techniques for the fabrication of novel nanocrystal aerogels. In this work, CdSe/CdS dot/rod NCs possessing two different CdSe core sizes were synthesized and converted into porous aerogel network structures. Temperature‐dependent steady‐state and time‐resolved photoluminescence measurements were performed to expand the understanding of the optical and electronic properties of these network structures generated from these two different building blocks and correlate their optical with the structural properties. These investigations reveal the influence of network formation and aerogel production on the network‐forming nanocrystals. Based on the two investigated NC building blocks and their aerogel networks, mixed network structures with various ratios of the two building blocks were produced and likewise optically characterized. Since the different building blocks show diverse optical response, this technique presents a straightforward way to color‐tune the resulting networks simply by choosing the building block ratio in connection with their quantum yield.
Information seeking and health anxiety during the COVID‐19 pandemic: The mediating role of catastrophic cognitions
Authors: Jagtap Shreya , Shamblaw Amanda L. , Rumas Rachel , Best Michael W. 
Published: November 2021

AbstractCognitive–behavioural models of health anxiety propose a positive association between information seeking and health anxiety; however, it is unclear the extent to which cognitive mechanisms may mediate this relationship. Catastrophic cognitions are one type of cognition that may mediate this relationship, and the COVID‐19 pandemic has presented an opportunity to examine these relationships within the context of a global health catastrophe. The current study investigated both cross‐sectional (N = 797) and longitudinal (n = 395) relationships between information seeking, health anxiety and catastrophizing during the pandemic. Data were collected using Amazon Mechanical Turk during April and May 2020. Information seeking and health anxiety were positively associated both cross‐sectionally and longitudinally (rs = .25–.29). Catastrophic cognitions significantly mediated the relationship between information seeking and health anxiety both cross‐sectionally and longitudinally. Developing effective methods of reducing information seeking and catastrophizing may serve to reduce health anxiety during global health crises such as the current pandemic.
Therapeutic targeting of SPIB/SPI1‐facilitated interplay of cancer cells and neutrophils inhibits aerobic glycolysis and cancer progression
Authors: Wang Jianqun , Wang Xiaojing , Guo Yanhua , Ye Lin , Li Dan , Hu Anpei , Cai Shuang , Yuan Boling , Jin Shikai , Zhou Yi , Li Qilan , Zheng Liduan , Tong Qiangsong 
Published: November 2021

AbstractBackgroundAs a metabolic reprogramming feature, cancer cells derive most of their energy from aerobic glycolysis, while its regulatory mechanisms and therapeutic strategies continue to be illusive.MethodsIntegrative analysis of publically available expression profile datasets was used to identify critical transcriptional regulators and their target glycolytic enzymes. The functions and acting mechanisms of transcriptional regulators in cancer cells were investigated by using in vitro and in vivo assays. The Kaplan–Meier curve and log‐rank assay were used to conduct the survival study.ResultsSalmonella pathogenicity island 1 (SPI1/PU.1), a haematopoietic transcription factor, was identified to facilitate glycolytic process, tumourigenesis, invasiveness, as well as metastasis of colon cancer cells, which was interplayed by tumour‐associated neutrophils. Mechanistically, neutrophils delivered SPI1 mRNA via extracellular vesicles, resulting in enhanced SPI1 expression of cancer cells. Through physical interaction with SPI1‐related protein (SPIB), SPI1 drove expression of glycolytic genes within cancer cells, which in turn induced polarization of neutrophils via glycolytic metabolite lactate. Depletion of neutrophils or SPIB–SPI1 interaction in cancer cells significantly inhibited glycolytic process, tumourigenesis and aggressiveness. Upregulation of SPI1 or SPIB was found to be associated with poor prognosis in patients suffering from colon cancer.ConclusionsTherapeutic targeting of SPIB/SPI1‐facilitated interplay of cancerous cells and neutrophils suppresses aerobic glycolysis and progression of cancer.
An efficient three‐factor user authentication scheme for industrial wireless sensor network with fog computing
Authors: Sahoo Shreeya Swagatika , Mohanty Sujata , Majhi Banshidhar 
Published: November 2021

SummaryUser authentication in industrial wireless sensor network (IWSN) is a security issue due to the hostile deployment of sensors in the field. The generated data from these sensors are generally processed in a cloud environment to provide on‐demand services. However, cloud computing suffers from several issues such as transmission latency and response time, and fog computing is hence introduced to resolve these issues. In the fog environment, the fog devices are placed near the user and responsible for intermediate computation and storage. This paper proposes a three‐factor‐based user authentication scheme for IWSN using fog computing (UASFI). The proposed scheme supports dynamic sensor node addition and smart card revocation phase. We employed the real‐or‐random (ROR) model for formal security analysis, which demonstrates the secrecy of the session key during communication. Furthermore, the simulation using NS2 and the comparison with existing schemes in terms of communicational and storage cost show that the proposed scheme is efficient for practical use.
Life impact of VA‐ECMO due to primary graft dysfunction in patients after orthotopic heart transplantation
Authors: M'Pembele René , Roth Sebastian , Stroda Alexandra , Buse Giovanna Lurati , Sixt Stephan U. , Westenfeld Ralf , Polzin Amin , Rellecke Philipp , Tudorache Igor , Hollmann Markus W. , Aubin Hug , Akhyari Payam , Lichtenberg Artur , Huhn Ragnar , Boeken Udo 
Published: November 2021

AbstractAimsPrimary graft dysfunction (PGD) is a feared complication after heart transplantation (HTX). HTX patients frequently receive veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) until graft recovery. Long‐term mortality of patients weaned from VA‐ECMO after HTX is comparable with non‐ECMO patients. However, impact on quality of life is unknown. This study investigated days alive and out of hospital (DAOH) as patient‐centred outcome in HTX patients at 1 year after surgery.Methods and resultsThis retrospective single‐centre cohort study included patients who underwent HTX at the University Hospital Düsseldorf, Germany, from 2010 to 2020. Main exposure was VA‐ECMO due to PGD. VA‐ECMO and non‐VA‐ECMO patients were compared regarding the primary endpoint DAOH at 1 year after HTX. Subgroup analysis for patients weaned from VA‐ECMO was performed. In total, 144 patients were included into analysis; 1 year mortality was significantly lower in non‐ECMO patients [non‐ECMO 14.3% (14/98) vs. VA‐ECMO 34.8% (16/46), adjusted hazard ratio: 0.32, 95% confidence interval: 0.15–0.74; P = 0.002]. Mortality did not differ significantly between patients weaned from VA‐ECMO and non‐ECMO patients [non‐ECMO 14.3% (14/98) vs. VA‐ECMO (weaned) 18.9% (7/37), adjusted hazard ratio: 0.72, 95% confidence interval: 0.27–1.90; P = 0.48]. DAOH were significantly higher in non‐ECMO patients compared with VA‐ECMO patients and patients weaned from VA‐ECMO [non‐ECMO vs. VA‐ECMO: median 310 (inter‐quartile range 277–327) days vs. 243 (0–288) days; P < 0.0001; non‐ECMO vs. VA‐ECMO (weaned): 310 (277–327) days vs. 253 (208–299) days; P < 0.0001]. These results were still significant after multivariable adjustment with forced entry of predefined covariables.ConclusionsDespite similar survival rates, VA‐ECMO due to PGD has a relevant life impact as defined by DAOH in the first year after HTX. As a more patient‐centred endpoint, DAOH may contribute to a more comprehensive assessment of outcome in HTX patients.