bluuebunny/crossref_metadata_2025_split huggingface dataset:
NIR‐Emitting Gold Nanoclusters–Modified Gelatin Nanoparticles as a Bioimaging Agent in Tissue
Authors: El‐Sayed Nesma , Trouillet Vanessa , Clasen Anne , Jung Gregor , Hollemeyer Klaus , Schneider Marc 
Published: November 2019

AbstractGold nanocluster (AuNC) synthesis using a well‐distinguished polymer for nanoparticle‐mediated drug delivery paves the way for developing efficient theranostics based on pharmaceutically accepted materials. Gelatin‐stabilized AuNCs are synthesized and modified by glutathione for tuning the emission spectra. Addition of silver ions enhances the fluorescence, reaching also high quantum yield (26.7%). A simplified model can be proposed describing the nanoclusters' properties–structure relationship based on X‐ray photoelectron spectroscopy data and synthesis sequence. Furthermore, these modifications improve fluorescence stability toward pH changes and enzymatic degradation, offering different AuNCs for various applications. The impact of nanocluster formation on gelatin structure integrity is investigated by Fourier transform infrared spectrometry and matrix‐assisted laser desorption/ionization time of flight mass spectroscopy, being important to further formulate gelatin nanoparticles (GNPs). The 218 nm‐sized NPs show no cytotoxicity up to 600 µg mL−1 and are imaged in skin, as a challenging autofluorescent tissue, by confocal microscopy, when transcutaneously delivered using dissolving microneedles. Linear unmixing allows simultaneous imaging of AuNCs–GNPs and skin with accurate signal separation. This underlines the great potential for bioimaging of this system to better understand nanomaterials' behavior in tissue. Additionally, it is drug delivery system also potentially serving as a theranostic system.
“Hot” in Plasmonics: Temperature‐Related Concepts and Applications of Metal Nanostructures
Authors: Kuppe Christian , Rusimova Kristina R. , Ohnoutek Lukas , Slavov Dimitar , Valev Ventsislav K. 
Published: November 2019

AbstractRecent advances in nonlinear optics, hot electrons for renewable energy (e.g., solar cells and water‐splitting), acousto‐optics, nanometalworking, nanorobotics, steam generation, and photothermal cancer therapy are reviewed here. In all these areas, one of the key enabling properties is the ability of metallic nanoparticles to harvest and control light at the subwavelength scale by supporting coherent electronic oscillations, called localized surface plasmon resonances (LSPRs). Various physical properties and potential areas of application emerge depending on the decay mechanism of the LSPR and, especially, depending on the considered timescale. The field of plasmonics has mainly been associated with manipulating electromagnetic near‐fields at the nanoscale, where absorption is an obstacle. However, plasmonic absorption leads to a stream of temperature‐related phenomena that have only recently attracted significant attention. The goal of this review is to highlight exciting new areas of research (such as nanorobotics, nanometalworking, or acousto‐optical techniques) and to survey the most recent progress in more established areas (such as hot electrons, photothermal therapy, and plasmonic steam generation). To set each research area in context, the text is organized around the thermal cycle of the nanoparticles.
Ultrahigh‐Performance Self‐Powered Flexible Photodetector Driven from Photogating, Piezo‐Phototronic, and Ferroelectric Effects
Authors: Shen Tien‐Lin , Chu Yu‐Wei , Liao Yu‐Kuang , Lee Wen‐Ya , Kuo Hao‐Chung , Lin Tai‐Yuan , Chen Yang‐Fang 
Published: November 2019

AbstractOwing to the need for dynamic, real‐time, and on‐site data collection in internet of things applications, the realization of ultra‐sensitive sensing networks with self‐powered, flexible, and lightweight devices has become an important issue for the development of sensor systems. In this work, a novel, high‐performance, self‐powered photodetector is achieved through the combination of photogating, piezo‐phototronic, and ferroelectric effect by incorporating a ferroelectric thin film of poly(vinylidene fluoride‐co‐trifluoroethylene) in a rationally designed device structure with suitable band alignment, which can modulate carrier transport behavior at the interface due to the internal electric field produced by light illumination, external strain, or voltage‐poled dipole. This enables photocurrent and overall device performance to improve significantly. The unprecedented photodetector presented in this study has several merits, including mechanical flexibility and light weight that allow it to adapt to arbitrary surface topology; additionally, its self‐powering capability and high reliability are urgently needed for the demanding functionality of devices for the development of next‐generation optoelectronic devices, spanning from wearable communication to unattended harsh environments with a human‐friendly interface.
Engineering the Active Site of an (S)‐Selective Amine Transaminase for Acceptance of Doubly Bulky Primary Amines
Authors: Land Henrik , Ruggieri Federica , Szekrenyi Anna , Fessner Wolf‐Dieter , Berglund Per 
Published: November 2019

AbstractA protein engineering approach for expanding the substrate scope of the (S)‐selective Chromobacterium violaceum amine transaminase is presented. Amino acid residues in the small binding pocket of the active site were targeted in order to increase the pocket size for acceptance of primary amines bearing two bulky groups. A highly sensitive fluorescence assay was then used to evaluate the generated enzyme variants for their activity towards propyl‐ and benzyl‐substituted screening substrates. The best variant, L59A/F88A, was successfully applied in the kinetic resolution of 1,2‐diphenylethylamine using different conditions and substrate loadings. The variant L59A/F88A generated enantiomerically pure (R)‐1,2‐diphenylethylamine with ee>99% under all tested conditions. The variant also holds great promise for synthesis of hydrophobic compounds as it shows optimum activity when 20‐30% (v/v) DMSO is applied as cosolvent. The variant L59A/F88A provides a great addition to the available catalyst toolbox for synthesis of chiral amines, as it is the first published (S)‐selective amine transaminase showing activity towards benzyl‐substituted primary amines.magnified image
Palladium‐Catalyzed Intramolecular Mizoroki‐Heck‐Type Reaction of Diarylmethyl Carbonates
Authors: Matsude Akihiro , Hirano Koji , Miura Masahiro 
Published: November 2019

AbstractA palladium‐catalyzed intramolecular Mizoroki‐Heck‐type reaction of diarylmethyl tert‐butyl carbonates has been developed. The reaction proceeds under external base‐free, neutral conditions to form the corresponding methyleneindanes in good yields only with liberation of CO2 and tBuOH. The resulting exo‐methylene moiety is reactive and thus a good synthetic handle for further manipulations. Additionally, the asymmetric synthesis is also possible through a Pd/chiral Mandyphos ligand‐mediated kinetic resolution. To the best of our knowledge, this is the first successful example of catalytic enantioselective Mizoroki‐Heck‐type reaction of secondary benzyl electrophiles.magnified image
Tracking Pathogen Infections by Time‐Resolved Chemical Proteomics
Authors: Zhang Ying , Kao Der‐Shyang , Gu Bing , Bomjan Rajdeep , Srivastava Mayank , Lu Haojie , Zhou Daoguo , Tao W. Andy 
Published: November 2019

AbstractStudying the dynamic interaction between host cells and pathogen is vital but remains technically challenging. We describe herein a time‐resolved chemical proteomics strategy enabling host and pathogen temporal interaction profiling (HAPTIP) for tracking the entry of a pathogen into the host cell. A novel multifunctional chemical proteomics probe was introduced to label living bacteria followed by in vivo crosslinking of bacteria proteins to their interacting host‐cell proteins at different time points initiated by UV for label‐free quantitative proteomics analysis. We observed over 400 specific interacting proteins crosslinked with the probe during the formation of Salmonella‐containing vacuole (SCV). This novel chemical proteomics approach provides a temporal interaction profile of host and pathogen in high throughput and would facilitate better understanding of the infection process at the molecular level.
Crystal‐Growth‐Dominated Fabrication of Metal–Organic Frameworks with Orderly Distributed Hierarchical Porosity
Authors: Li Hang , Meng Fanchen , Zhang Suoying , Wang Liguang , Li Matthew , Ma Lu , Zhang Weina , Zhang Wenlei , Yang Zhuhong , Wu Tianpin , Lee Sungsik , Huo Fengwei , Lu Jun 
Published: November 2019

AbstractConstructing architectures with hierarchical porosity has been widely considered as the most efficient way to bypass the problems related to slow mass transfer and inaccessibility of internal space in MOFs. Now, a crystal‐growth‐dominated strategy is proposed to fabricate hierarchically porous MOFs (HP‐MOFs). When the crystal growth is dominated by the monomer attachment, the aggregation of nonionic surfactant or polymer can be easily captured and released during the crystal growth process, resulting in the formation and ordering hierarchical pores along the radial direction. Owing to the accelerated mass diffusion and more exposed active sites of this design, HP‐MOFs exhibited an enhanced catalytic efficiency in styrene oxidation.
Structure Determination of Alkynyl‐Protected Gold Nanocluster Au22(tBuC≡C)18 and Its Thermochromic Luminescence
Authors: Han Xu‐Shuang , Luan Xinqi , Su Hai‐Feng , Li Jiao‐Jiao , Yuan Shang‐Fu , Lei Zhen , Pei Yong , Wang Quan‐Ming 
Published: November 2019

AbstractAn alkynyl‐protected gold nanocluster, Au22(tBuC≡C)18 (1), has been synthesized and its structure has been determined by single‐crystal X‐ray diffraction. The molecular structure consists of a Au13 cuboctahedron kernel and three [Au3(tBuC≡C)4] trimeric staples. The cluster 1 has strong luminescence in the solid state with a 15 % quantum yield, and it displays interesting thermochromic luminescence as revealed by temperature‐dependent emission spectra. The enhanced room‐temperature emission is characterized as thermally activated delayed fluorescence.
Multiple Bonding Between Group 3 Metals and Fe(CO)3−
Authors: Wang Jia‐Qi , Chi Chaoxian , Hu Han‐Shi , Li Xiang , Luo Mingbiao , Li Jun , Zhou Mingfei 
Published: November 2019

AbstractHeteronuclear Group 3 metal/iron carbonyl anion complexes ScFe(CO)3−, YFe(CO)3−, and LaFe(CO)3− are prepared in the gas phase and studied by mass‐selective infrared (IR) photodissociation spectroscopy as well as quantum‐chemical calculations. All three anion complexes are characterized to have a metal–metal‐bonded C3v equilibrium geometry with all three carbonyl ligands bonded to the iron center and a closed‐shell singlet electronic ground state. Bonding analyses reveal that there are multiple bonding interactions between the bare group‐3 elements and the Fe(CO)3− fragment. Besides one covalent electron‐sharing metal–metal σ bond and two dative π bonds from Fe to the Group 3 metal, there is additional multicenter covalent bonding with the Group 3 atom bonded to Fe and the carbon atoms.
Sublimable Spin‐Crossover Complexes: From Spin‐State Switching to Molecular Devices
Authors: Kumar Kuppusamy Senthil , Ruben Mario 
Published: November 2019

AbstractSpin‐crossover (SCO) active transition metal complexes are an important class of switchable molecular materials due to their bistable spin‐state switching characteristics at or around room temperature. Vacuum‐sublimable SCO complexes are a subclass of SCO complexes suitable for fabricating ultraclean spin‐switchable films desirable for applications, especially in molecular electronics/spintronics. Consequently, on‐surface SCO of thin‐films of sublimable SCO complexes have been studied employing spectroscopy and microscopy techniques, and results of fundamental and technological importance have been obtained. This Review provides complete coverage of advances made in the field of vacuum‐sublimable SCO complexes: progress made in the design and synthesis of sublimable functional SCO complexes, on‐surface SCO of molecular and multilayer thick films, and various molecular and thin‐film device architectures based on the sublimable SCO complexes.
Iridium‐Catalyzed Hydrochlorination and Hydrobromination of Alkynes by Shuttle Catalysis
Authors: Yu Peng , Bismuto Alessandro , Morandi Bill 
Published: November 2019

AbstractDescribed herein are two different methods for the synthesis of vinyl halides by a shuttle catalysis based iridium‐catalyzed transfer hydrohalogenation of unactivated alkynes. The use of 4‐chlorobutan‐2‐one or tert‐butyl halide as donors of hydrogen halides allows this transformation in the absence of corrosive reagents, such as hydrogen halides or acid chlorides, thus largely improving the functional‐group tolerance and safety profile of these reactions compared to the state‐of‐the‐art. This method has granted access to alkenyl halide compounds containing acid‐sensitive groups, such as tertiary alcohols, silyl ethers, and acetals. The synthetic value of those methodologies has been demonstrated by gram‐scale synthesis where low catalyst loading was achieved.
Enriched Surface Oxygen Vacancies of Photoanodes by Photoetching with Enhanced Charge Separation
Authors: Feng Shijia , Wang Tuo , Liu Bin , Hu Congling , Li Lulu , Zhao Zhi‐Jian , Gong Jinlong 
Published: November 2019

AbstractA facile photoetching approach is described that alleviates the negative effects from bulk defects by confining the oxygen vacancy (Ovac) at the surface of BiVO4 photoanode, by 10‐minute photoetching. This strategy could induce enriched Ovac at the surface of BiVO4, which avoids the formation of excessive bulk defects. A mechanism is proposed to explain the enhanced charge separation at the BiVO4 /electrolyte interface, which is supported by density functional theory (DFT) calculations. The optimized BiVO4 with enriched surface Ovac presents the highest photocurrent among undoped BiVO4 photoanodes. Upon loading FeOOH/NiOOH cocatalysts, photoetched BiVO4 photoanode reaches a considerable water oxidation photocurrent of 3.0 mA cm−2 at 0.6 V vs. reversible hydrogen electrode. An unbiased solar‐to‐hydrogen conversion efficiency of 3.5 % is realized by this BiVO4 photoanode and a Si photocathode under 1 sun illumination.
Construction of Quaternary Carbon Center by Catalytic Asymmetric Alkylation of 3‐Arylpiperidin‐2‐ones Under Phase‐Transfer Conditions
Authors: Inukai Tomoaki , Kano Taichi , Maruoka Keiji 
Published: November 2019

AbstractA highly enantioselective synthesis of δ‐lactams having a chiral quaternary carbon center at the α‐position has been developed through an asymmetric alkylation of 3‐arylpiperidin‐2‐ones under phase‐transfer conditions. In this transformation, a 2,2‐diarylvinyl group on the δ‐lactam nitrogen atom plays a crucial role as a novel protecting group and an achiral auxiliary for improving both yield and enantioselectivity of the reaction.
Image‐Based Morphological Profiling Identifies a Lysosomotropic, Iron‐Sequestering Autophagy Inhibitor
Authors: Laraia Luca , Garivet Guillaume , Foley Daniel J. , Kaiser Nadine , Müller Sebastian , Zinken Sarah , Pinkert Thomas , Wilke Julian , Corkery Dale , Pahl Axel , Sievers Sonja , Janning Petra , Arenz Christoph , Wu Yaowen , Rodriguez Raphaël , Waldmann Herbert 
Published: November 2019

AbstractChemical proteomics is widely applied in small‐molecule target identification. However, in general it does not identify non‐protein small‐molecule targets, and thus, alternative methods for target identification are in high demand. We report the discovery of the autophagy inhibitor autoquin and the identification of its molecular mode of action using image‐based morphological profiling in the cell painting assay. A compound‐induced fingerprint representing changes in 579 cellular parameters revealed that autoquin accumulates in lysosomes and inhibits their fusion with autophagosomes. In addition, autoquin sequesters Fe2+ in lysosomes, resulting in an increase of lysosomal reactive oxygen species and ultimately cell death. Such a mechanism of action would have been challenging to unravel by current methods. This work demonstrates the potential of the cell painting assay to deconvolute modes of action of small molecules, warranting wider application in chemical biology.
Comparative effects of two different crosslinkers on the properties of vegetable oil‐based polyurethanes
Authors: Meiorin Cintia , Calvo‐Correas Tamara , Mosiewicki Mirna Alejandra , Aranguren Mirta Inés , Corcuera Maria Angeles , Eceiza Arantxa 
Published: November 2019

ABSTRACTThermoset polyurethanes (PUs) were prepared from a polyol derived from castor oil, 4,4′‐methylene diphenyl diisocyanate (MDI) and different trifunctional low‐molecular‐weight crosslinkers, biobased glycerol (Gly) and petroleum‐derived trimethylolpropane (TMP). The synthesis was carried out in bulk and without catalyst via one‐step polymerization varying the components equivalent weight ratio, Polyol:MDI:Gly and Polyol:MDI:TMP, respectively. The physicochemical, morphological, thermal, dynamic–mechanical, and mechanical properties of the PUs were determined. The success of the reaction between the polyol and MDI was confirmed by Fourier transform infrared spectroscopy. The dynamic–mechanical and the mechanical properties as well as hardness were determined and related to the concentration of the low‐molecular‐weight crosslinkers utilized (Gly or TMP). However, important differences were observed between the synthesized two series, due to phase separation produced during the curing reaction, which affected more the materials prepared from TMP. Scanning electron microscopy images and dynamic–mechanical results confirmed this difference, related to the reactivity of primary and secondary hydroxyls present in the crosslinkers. Thermogravimetric analysis also showed to be sensible to the different structure of the crosslinkers with TMP leading to more thermally stable samples. Finally, measurements of water contact angle indicated that the surfaces were mostly hydrophobic with minor differences between the samples. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48741.
Effect of phenolic compounds from the rind of Punica granatum on the activity of three metabolism‐related enzymes
Authors: Ahmed Mohamed H. , Aldesouki Hala M. , Badria Farid A. 
Published: November 2019

AbstractEnzyme activity modulation by synthetic compounds provide strategies combining the inhibitory and therapeutic mode of action of the confirmed inhibitors. However, natural modulators could offer a valuable alternative for synthetic ones for the treatment of different chronic diseases (diabetes, hypertension, cancer) due to the numerous side effects of the latter. In vitro screening assays were conducted for Punica granatum rind methanolic extract against three metabolism‐related enzymes: α‐amylase, tyrosinase, and hyaluronidase. The obtained results showed that the examined extract retained high multitarget inhibition with inhibition percentages 31.5 ± 1.3%, 75.9 ± 4.7%, and 68.5 ± 5.3% against α‐amylase, tyrosinase, and hyaluronidase, respectively. Bioguided fractionation of P. granatum rind extract revealed that quercetin is the major active compound with inhibitory activities: 54.3 ± 2.7%, 94.2 ± 3.5%, and 90.9 ± 2.7% against α‐amylase, tyrosinase, and hyaluronidase, respectively. Kinetic studies of enzymes showed that quercetin inhibition was noncompetitive, uncompetitive, and competitive for α‐amylase, tyrosinase, and hyaluronidase, respectively. The molecular docking of quercetin with α‐amylase and hyaluronidase showed high binding energy with different bonds stabilizing the ligand–protein complex. Compiling all obtained results led to conclude that both P. granatum rind extract and quercetin have multitarget activities with potential therapeutic applications in many metabolic disorders.
Study on the interaction of anti‐inflammatory drugs with human serum albumin using molecular docking, quantitative structure–activity relationship, and fluorescence spectroscopy
Authors: Mohammadnia F. , Fatemi M.H. , Taghizadeh S.M. 
Published: November 2019

AbstractThe interaction of 14 anti‐inflammatory drugs with human serum albumin (HSA) was investigated using fluorescence quenching, molecular docking studies, and quantitative structure–activity relationship (QSAR) methodology. Binding of anti‐inflammatory drugs to HSA plays a fundamental role in their transport, distribution, delivery, and elimination. Binding constants of these drugs to HSA, obtained using the fluorescence quenching method, were within the range 0.01 × 104 M−1 (acetaminophen) to 1881.05 × 104 M−1 (meloxicam). Binding sites and binding constants of these anti‐inflammatory drugs were estimated using molecular docking. Inspection of the obtained values for docking score, logKb and Kb, showed that the drugs in this data set have a relatively strong binding constant for HSA. QSAR modelling was applied for binding constants obtained from fluorescence quenching and theoretical molecular descriptors. This modelling led to a linear two‐parameter model with a correlation coefficient of 0.95 and adequate robustness. The descriptor results showed the importance of a bonding network and electronegativity as the discriminative structural factors in binding affinity for the HSA molecule.
Successful eco‐innovators: Exploring the association between open inbound knowledge strategies and the performance of eco‐innovative firms
Authors: Moreno‐Mondéjar Lourdes , Triguero Ángela , Sáez‐Martínez Francisco José 
Published: November 2019

AbstractThe main purpose of this paper is to analyse the association between open inbound knowledge strategies and the performance of eco‐innovative firms in the food and beverage industry. We propose a mixed framework based on the eco‐innovation literature and the open innovation approach. We consider the characteristics in a traditional sector based upon a resource‐based perspective. Three types of firms are distinguished in terms of their sales growth in the Spanish food industry from the least to the most successful eco‐innovators. Using multinomial logistic regression models, it is shown that the diversity of collaborators (breadth of external sources of knowledge) and joint adoption of product and process eco‐innovations are positively associated with the probability of achieving high sales growth. Moreover, we find an inverted U‐shaped relationship between the breadth of the external search and firm performance, but only for the group of the most successful firms. Moreover, operational flexibility, knowledge‐based capabilities and company size are also positively related to the group of successful eco‐innovators.