bluuebunny/crossref_metadata_2025 huggingface dataset:
Compositional effect on the deformation behavior of polyurethane pressure‐sensitive adhesive thin films
Authors: Akram Nadia , Zia Khalid Mahmood , Saeed Muhammad , Khosa Muhammad Kaleem , Khan Waheed Gul , Arain Muhammad Amir
Published: August 2019

The careful selection of composition for thin films is a critical issue to deal with. A mere change in stoichiometry deforms the thin adhesive films brusquely. In this work, a series of thin films of polyurethane‐based pressure‐sensitive adhesives have been synthesized and the factors responsible for collapsing of the adhesive films have been investigated. The pressure‐sensitive adhesives have been prepared by the use of polypropylene glycol and hydroxyl‐terminated polybutadiene macrodiols along with isophorone diisocyanate. The 40 wt % of solid contents have been maintained with hard segment contents of 28–64 wt %. Thin films of 70–100 μm have been utilized for probe‐tack analysis. The high storage modulus up to 1.83 MPa has been observed from dynamic mechanical analysis of PSA films. The adhesion properties evaluated by consideration of the ratio of the loss tangent to the storage modulus (tanδ/E′) for comparison resulted in the values from 0.03 to 0.45 MPa−1. The glass‐transition temperature is also appeared to be a decisive factor with variation from original values. The high‐molecular weight of macrodiols resulted in the loss of adhesiveness. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48395.
Electrochemically Generated γ‐LixV2O5 as Insertion Host for High‐Energy Li‐Ion Capacitors
Authors: Divya M. L. , Aravindan Vanchiappan
Published: August 2019

In this study, we explored the feasibility of using electrochemically generated γ‐LixV2O5 as an insertion‐type anode in the lithium‐ion capacitor (LIC) with activated carbon (AC) as a cathode. Along with the native form of V2O5, their carbon composites are also used as the electrode material which is prepared by high‐energy ball milling. The electrochemical pre‐lithiation strategy is used to generate the desired γ‐phase of V2O5 (γ‐LixV2O5). Under the optimized mass loading conditions, the LICs are assembled with γ‐LixV2O5 as anode and AC as a cathode in the organic medium. Among the different LICs fabricated, AC/γ‐LixV2O5‐BM50 configuration delivered an energy density of 33.91 Wh kg−1 @ 0.22 kW kg−1 with excellent capacity retention characteristics. However, a dramatic increase in energy density (43.98 Wh kg−1@0.28 kW kg−1) is noted after the electrolyte modification with fluoroethylene carbonate. The high temperature performance of the assembled LIC is also studied and found that γ‐LixV2O5 phase can be used as a potential battery‐type component to construct high‐performance hybrid charge storage devices.
A Functionally Graded Cathode Architecture for Extending the Cycle‐Life of Potassium‐Oxygen Batteries
Authors: Gilmore Paul , Sundaresan Vishnu Baba
Published: August 2019

Invited for this month's cover picture is the group of Prof. Vishnu Baba Sundaresan. The cover picture shows a functionally‐graded cathode for potassium‐oxygen batteries, regulating K+‐ion and oxygen transport at the trilayer electrolyte‐cathode‐air interface. Read the full text of the article at 10.1002/batt.201900025
An optimal Bayesian predictive probability design for phase II clinical trials with simple and complicated endpoints
Authors: Guo Beibei , Liu Suyu
Published: August 2019

Most existing phase II clinical trial designs focus on conventional chemotherapy with binary tumor response as the endpoint. The advent of novel therapies, such as molecularly targeted agents and immunotherapy, has made the endpoint of phase II trials more complicated, often involving ordinal, nested, and coprimary endpoints. We propose a simple and flexible Bayesian optimal phase II predictive probability (OPP) design that handles binary and complex endpoints in a unified way. The Dirichlet‐multinomial model is employed to accommodate different types of endpoints. At each interim, given the observed interim data, we calculate the Bayesian predictive probability of success, should the trial continue to the maximum planned sample size, and use it to make the go/no‐go decision. The OPP design controls the type I error rate, maximizes power or minimizes the expected sample size, and is easy to implement, because the go/no‐go decision boundaries can be enumerated and included in the protocol before the onset of the trial. Simulation studies show that the OPP design has satisfactory operating characteristics.
O2 sensitivity and H2 production activity of hydrogenases—A review
Authors: Lu Yuan , Koo Jamin
Published: August 2019

Hydrogenases are metalloproteins capable of catalyzing the interconversion between molecular hydrogen and protons and electrons. The iron–sulfur clusters within the enzyme enable rapid relay of electrons which are either consumed or generated at the active site. Their unparalleled catalytic efficiency has attracted attention, especially for potential use in H2 production and/or fuel cell technologies. However, there are limitations to using hydrogenases, especially due to their high O2 sensitivity. The subclass, called [FeFe] hydrogenases, are particularly more vulnerable to O2 but proficient in H2 production. In this review, we provide an overview of mechanistic and protein engineering studies focused on understanding and enhancing O2 tolerance of the enzyme. The emphasis is on ongoing studies that attempt to overcome O2 sensitivity of the enzyme while it catalyzes H2 production in an aerobic environment. We also discuss pioneering attempts to utilize the enzyme in biological H2 production and other industrial processes, as well as our own perspective on future applications.
The influence of lignin migration and relocation during steam pretreatment on the enzymatic hydrolysis of softwood and corn stover biomass substrates
Authors: Takada Masatsugu , Chandra Richard P. , Saddler John N.
Published: August 2019

To be effective, steam pretreatment is typically carried out at temperatures/pressures above the glass transition point (Tg) of biomass lignin so that it can partly fluidize and relocate. The relocation of Douglas‐fir and corn stover derived lignin was compared with the expectation that, with the corn stover lignin's lower hydrophobicity and molecular weight, it would be more readily fluidized. It was apparent that the Tg of lignin decreased as the moisture increased, with the easier access of steam to the corn stover lignin promoting its plasticization. Although the softwood lignin was more recalcitrant, when it was incorporated onto filter paper, it too could be plasticized, with its relocation enhancing enzymatic hydrolysis. When lignin recondensation was minimized, the increased hydrophobicity suppressed lignin relocation. It was apparent that differences in the accessibility of the lignin present in Douglas‐fir and corn stover to steam significantly impacted lignin fluidization, relocation, and subsequent cellulose hydrolysis.
Consequences of trace metal variability and supplementation on Chinese hamster ovary (CHO) cell culture performance: A review of key mechanisms and considerations
Authors: Graham Ryan J. , Bhatia Hemlata , Yoon Seongkyu
Published: August 2019

Trace metals are supplied to chemically‐defined media (CDM) for optimal Chinese hamster ovary (CHO) cell culture performance during the production of monoclonal antibodies and other therapeutic proteins. However, lot‐to‐lot and vendor‐to‐vendor variability in raw materials consequently leads to an imbalance of trace metals that are supplied to CDM. This imbalance can yield detrimental effects rooted in several primary mechanisms and pathways including oxidative stress, apoptosis, lactate accumulation, and unfavorable glycan synthesis. Recent research endeavors involve supplying zinc, copper, and manganese to CDM in excess to further maximize culture productivity and product quality. These treatments significantly impact critical quality attributes and furthermore highlight the degree to which trace metal availability can affect CHO cell culture performance. This review highlights the role of trace metal variability, supplementation, and interplay on key cellular mechanisms responsible for overall culture performance and the production and quality of therapeutic proteins.
Two years clinical outcomes with the state‐of‐the‐art PCI for the treatment of bifurcation lesions: A sub‐analysis of the SYNTAX II study
Authors: Modolo Rodrigo , Kogame Norihiro , Komiyama Hidenori , Chichareon Ply , de Vries Ton , Tomaniak Mariusz , Chang Chun Chin , Takahashi Kuniaki , Walsh Simon , Lesiak Maciej , Moreno Raul , Farrooq Vasim , Escaned Javier , Banning Adrian , Onuma Yoshinobu , Serruys Patrick W.
Published: August 2019

Background

Bifurcation PCI is associated with a lower rate of procedural success, especially in multivessel disease patients. We aimed to determine the impact of bifurcation treatment on 2‐years clinical outcomes when a state‐of‐the‐art PCI strategy (heart team decision‐making using the SYNTAX score II, physiology guided coronary stenosis assessment, thin strut bioresorbable polymer drug‐eluting stent, and intravascular ultrasound guidance) is followed.

Methods

Three‐vessel disease patients enrolled in the SYNTAX II trial (n = 454) were categorized in patients with (a) ≥1 treated bifurcation (n = 126), and (b) without bifurcation (n = 281). The primary endpoint was the occurrence of major adverse cardio and cerebrovascular events (MACCE—a composite of all‐cause death, stroke, any myocardial infarction, or any revascularization) at 2 years. Secondary endpoints were the occurrence of target lesion failure (TLF) defined as cardiac death, target‐vessel myocardial infarction and ischemia‐driven target lesion revascularization, and the individual components of the composite primary endpoint, as well as stent thrombosis.

Results

A total of 145 bifurcation were treated in 126 patients. At 2 years, MACCE occurred in 75/407 patients (20.7% for bifurcation versus 17.5% for nonbifurcation, hazard ratio [HR] of 1.28, CI95% 0.78–2.08, p = .32). TLF presented a trend toward higher occurrence in bifurcation (16.8% vs. 10.8%, HR 1.75, CI95% 0.99–3.09, p = .053). Definite stent thrombosis did not differ at 2‐year between groups (0.8% for the bifurcation vs. 0.7% for the nonbifurcation, p = .92).

Conclusion

Bifurcation treatment in patients with three‐vessel disease undergoing state‐of‐the‐art PCI had similar event rate of MACCE but was associated with a trend toward higher incidence of TLF compared with nonbifurcation lesions.
One‐Pot Three‐Step Consecutive Transformation of L‐α‐Amino Acids to (R)‐ and (S)‐Vicinal 1,2‐Diols via Combined Chemical and Biocatalytic Process
Authors: Zhang Jian‐Dong , Zhao Jian‐Wei , Gao Li‐Li , Zhao Jing , Chang Hong‐Hong , Wei Wen‐Long
Published: August 2019

Optically pure vicinal 1,2‐diols are versatile chiral building blocks in the fine chemical and pharmaceutical industries. L‐α‐amino acid is a good feedstock source for high value‐added product production since it is inexpensive and renewable. However, conversion of L‐α‐amino acids to enantioenriched vicinal 1,2‐diols remains a significant challenge. In this study, combining a simple chemical process and a three‐enzyme cascade biocatalysis system, we have successfully implemented a one‐pot sequential process for the transformation of L‐α‐amino acids into enantiopure vicinal 1,2‐diols in aqueous medium. Firstly, the NaBH4‐H2SO4 system converted L‐α‐amino acids to (S)‐amino alcohols via amino acid carboxyl reduction. Secondly, the three‐enzyme (transaminase, carbonyl reductase and glucose dehydrogenase) cascade biocatalysis system converted amino alcohols to enantiopure vicinal 1,2‐diols via amino alcohol deamination, α‐hydroxy ketone asymmetric reduction and cofactor regeneration. Taking advantage of the two different reaction systems, chiral vicinal 1,2‐diols could be obtained from L‐α‐amino acids with high yields (69–90 %) and excellent ee values (91–>99 % ee).
In‐situ One‐Step Preparation of Nickel‐Tipped N‐doped Carbon Nanotubes for Oxygen Reduction
Authors: Huai Jie , Ma Kongshuo , Lu Yizhong , Chen Tao , Zhao Zhenlu
Published: August 2019

Here, we successfully synthesized N‐doped carbon nanotubes embedded with nickel‐based nanoparticles on the top (N‐CNTs/E‐NNPs) by directly procedural calcination of melamine and nickel foam at 520 °C, 540 °C and 700 °C in Ar. When applied for oxygen reduction reaction (ORR), the onset potential and half‐wave potential are 0.96 V and 0.86 V in 0.1 M KOH, comparable to that of the commercial 10 wt% Pt/C. Moreover, the hybrids possess higher stability and better methanol tolerance. Additionally, the Tafel slope of N‐CNTs/E‐NNPs is 76 mV dec−1 in 0.1 M KOH, lower than 83 mV dec−1 of the commercial 10 wt% Pt/C, demonstrating a good kinetic process. The remarkable features are mainly ascribed to synergistic enhancement effect from N‐rich doped carbon nanotubes (N‐CNTs) and embedded Ni‐based nanoparticles on the top, promoting mass and electrons transport, enhancing the activity of active sites and making it a promising highly efficient non‐precious metal ORR catalyst.
Biochemical Conversion of Microalgae Biomass into Biofuel
Authors: Hossain S. M. Zakir
Published: August 2019

Biofuel production via microalgae is a promising and sustainable alternative to replace the typical fossil fuel that is the main contributor to the global warming. However, for a cost‐effective biofuel production, further advanced research is still needed for large‐scale operation. This article is a tutorial review on conversion processes of microalgae into biofuel, with emphasis on biochemical conversion. The following topics are discussed: (i) microalgae biomass and its composition, (ii) thermochemical conversion, (iii) chemical conversion, and (iv) biochemical conversion. In addition, various aspects of anaerobic digestion, digester designs, and effects of operating conditions on the production of methane, bioethanol, and biohydrogen are discussed. The general kinetics of biomass conversion into biofuel is presented. This study suggests, if that biomass contains less than 50 % moisture, then it is recommended to use the direct combustion method; otherwise, biochemical conversion is the most suitable process to biofuel production.
Preparative Protein Crystallization
Authors: Hubbuch Jürgen , Kind Matthias , Nirschl Hermann
Published: August 2019

Preparative protein crystallization can possibly replace one or more chromatographic steps in downstream processing. The development of such crystallization processes is demanding: first, promising principal crystallization conditions must be identified; second, details about the process must be defined; and third, the crystals have to be separated from the mother liquor without putting harm of their crystalline integrity. State‐of‐the‐art about these three steps is developing fast by (i) employing new screening methods which are based on fundamental understanding of the interaction of the protein molecules, (ii) application of existing concepts of technical bulk crystallization of small molecules to preparative protein crystallization, and (iii) making available specific gentle separation machinery.
Low‐Temperature Fast Production of Carbon and Acetic Acid Dual‐Promoted Pd/C Catalysts
Authors: Yao Xiuchao , Ni Lin , Yu Chang , Zhang Mengdi , Wei Qianbing , Huang Huawei , Guo Wei , Huang Hongling , Chang Jiangwei , Qiu Jieshan
Published: August 2019

The Pd/C catalysts are widely used in synthesis of fine chemicals in industry, but their production suffers from a complicated two‐step process involving impregnation and reduction, and requires large amounts of solvents and reductant, which would lead to a series of issues such as time consumption, resource waste and environmental pollution. Herein, ultra‐small Pd nanoparticles uniformly anchored on carbon nanotubes (Pd/CNTs) were synthesized by using a one‐pot and low‐temperature reduction strategy. The present process/technology is very sensitive to and controlled by the supports and solvents, and the carbon support and acetic acid synergistically play crucial and decisive roles in the fast production of Pd/C catalysts. Also, the used solvents can be recycled and reutilized, which meets the requirements of sustainable chemistry and green economy. When the as‐obtained Pd/CNTs catalyst was used to catalyze the oxidation of benzyl alcohol to benzaldehyde, it achieved a conversion efficiency as high as 99.3 % and a high selectivity up to >99.9 %. The simple, scalable and environmentally friendly strategy can be extended to anchor Pd nanoparticles on various carbon substrates, which sheds a new light on the synthesis of Pd/C catalysts.
Transient Phosphenium and Arsenium Ions versus Stable Stibenium and Bismuthenium Ions
Authors: Olaru Marian , Duvinage Daniel , Lork Enno , Mebs Stefan , Beckmann Jens
Published: August 2019

Fluoride abstraction from bis‐m‐terphenylelement fluorides (2,6‐Mes2C6H3)2EF (E=P, As) generated the highly reactive phosphenium ion [(2,6‐Mes2C6H3)2P]+ and the arsenium ion [(2,6‐Mes2C6H3)2As]+, which immediately underwent intramolecular electrophilic substitution and formation of an 1,2,4‐trimethyl‐6‐mesityl‐5‐m‐terphenyl‐benzo[b]phospholium ion and an 1,2,4‐trimethyl‐6‐mesityl‐5‐m‐terphenyl‐benzo[b]arsolium ion, respectively. The formation of the latter involved a methyl group migration from the ortho‐position of a flanking mesityl group to the meta‐position. This reactivity of [(2,6‐Mes2C6H3)2E]+ (E=P, As) is in sharp contrast to the related stibenium ion [(2,6‐Mes2C6H3)2Sb]+ and bismuthenium ion [(2,6‐Mes2C6H3)2Bi]+, which have been recently isolated and fully characterized (Angew. Chem. Int. Ed. 2018, 57, 10080–10084). On the basis of DFT calculations, a mechanism for the rearrangement of the phosphenium and arsenium ions into the phospholium and arsolium ions is proposed, which is not feasible for the stibenium and bismuthenium ions.
The Plasticity of the Carbohydrate Recognition Domain Dictates the Exquisite Mechanism of Binding of Human Macrophage Galactose‐Type Lectin
Authors: Diniz Ana , Coelho Helena , Dias Jorge S. , van Vliet Sandra J. , Jiménez‐Barbero Jesús , Corzana Francisco , Cabrita Eurico J. , Marcelo Filipa
Published: August 2019

The human macrophage galactose‐type lectin (MGL), expressed on macrophages and dendritic cells (DCs), modulates distinct immune cell responses by recognizing N‐acetylgalactosamine (GalNAc) containing structures present on pathogens, self‐glycoproteins, and tumor cells. Herein, NMR spectroscopy and molecular dynamics (MD) simulations were used to investigate the structural preferences of MGL against different GalNAc‐containing structures derived from the blood group A antigen, the Forssman antigen, and the GM2 glycolipid. NMR spectroscopic analysis of the MGL carbohydrate recognition domain (MGL‐CRD, C181‐H316) in the absence and presence of methyl α‐GalNAc (α‐MeGalNAc), a simple monosaccharide, shows that the MGL‐CRD is highly dynamic and its structure is strongly altered upon ligand binding. This plasticity of the MGL‐CRD structure explains the ability of MGL to accommodate different GalNAc‐containing molecules. However, key differences are observed in the recognition process depending on whether the GalNAc is part of the blood group A antigen, the Forssman antigen, or GM2‐derived structures. These results are in accordance with molecular dynamics simulations that suggest the existence of a distinct MGL binding mechanism depending on the context of GalNAc moiety presentation. These results afford new perspectives for the rational design of GalNAc modifications that fine tune MGL immune responses in distinct biological contexts, especially in malignancy.
Insights into the Electrochemical Polymerization of [Mo3S13]2− Generating Amorphous Molybdenum Sulfide
Authors: Duong Tuan M. , Nguyen Phuc D. , Nguyen Anh D. , Le Ly T. , Nguyen Loan T. , Pham Hai V. , Tran Phong D.
Published: August 2019

Amorphous molybdenum sulfide is an attractive electrode material for Li/Mg batteries and an efficient Pt‐free catalyst for the hydrogen evolution reaction in water. By using the electrochemical quartz crystal microbalance (EQCM) analysis, new insights were gained into the electrochemical polymerization of the [Mo3S13]2− cluster, which generates amorphous molybdenum sulfide thin films. In this work, it is shown that, at the anodic potential, a two‐electron oxidative elimination of the terminal disulfide ligand within the [Mo3S13]2− cluster induces the polymerization. A reductive elimination of the terminal disulfide ligand also occurs at the cathodic potential, inducing the polymerization. However, in sharp contrast to the anodic polymerization, according to which the film growth is rapid, the cathodic polymerization competes with the electrochemical reductive corrosion of the readily grown film, therefore occurring at a significant lower growth rate.
Structural and Mechanistic Insights into CO2 Activation by Nitrogenase Iron Protein
Authors: Rettberg Lee A. , Stiebritz Martin T. , Kang Wonchull , Lee Chi Chung , Ribbe Markus W. , Hu Yilin
Published: August 2019

The Fe protein of nitrogenase catalyzes the ambient reduction of CO2 when its cluster is present in the all‐ferrous, [Fe4S4]0 oxidation state. Here, we report a combined structural and theoretical study that probes the unique reactivity of the all‐ferrous Fe protein toward CO2. Structural comparisons of the Azotobacter vinelandii Fe protein in the [Fe4S4]0 and [Fe4S4]+ states point to a possible asymmetric functionality of a highly conserved Arg pair in CO2 binding and reduction. Density functional theory (DFT) calculations provide further support for the asymmetric coordination of O by the “proximal” Arg and binding of C to a unique Fe atom of the all‐ferrous cluster, followed by donation of protons by the proximate guanidinium group of Arg that eventually results in the scission of a C−O bond. These results provide important mechanistic and structural insights into CO2 activation by a surface‐exposed, scaffold‐held [Fe4S4] cluster.
A Tetra‐Porphyrin Host Exhibiting Interannular Cooperativity
Authors: Murphy Rhys B. , Pham Duc‐Truc , Johnston Martin R.
Published: August 2019

Recently identified as another form of cooperativity, interannular cooperativity is rarely observed in supramolecular chemistry. A tetra‐porphyrin molecular tweezer with two bis‐porphyrin binding sites is reported that exhibits archetypal interannular cooperativity when complexing 1,4‐diazabicyclo[2.2.2]octane (DABCO). The UV/Vis titration data best supported a 1:2 plus 2:2 plus 1:4 complexation model (host:guest), giving K12=6.32×1013 m−2, K22=3.04×1020 m−3, and K14=1.92×1016 m−4 in CHCl3. The NMR titration data supported the formation of two sandwich species, including tetra‐porphyrin⋅(DABCO)2 as the major species, although there are speciation differences between UV/Vis and NMR concentrations. Using statistical analysis, interannular cooperativity (γ) for tetra‐porphyrin⋅(DABCO)2 was determined to be negative (γ=2.41×10−3), which may be explained by DABCO being too small to be optimally bound simultaneously at both bis‐porphyrin binding sites.
Vinyl Triflate–Aldehyde Reductive Coupling–Redox Isomerization Mediated by Formate: Rhodium‐Catalyzed Ketone Synthesis in the Absence of Stoichiometric Metals
Authors: Shuler William G. , Swyka Robert A. , Schempp Tabitha T. , Spinello Brian J. , Krische Michael J.
Published: August 2019

Direct conversion of aldehydes to ketones is achieved via rhodium‐catalyzed vinyl triflate‐aldehyde reductive coupling‐redox isomerization mediated by potassium formate. This method circumvents premetalated C‐nucleophiles and discrete redox manipulations typically required to form ketones from aldehydes.
Phosphinoboration of Diazobenzene: Intramolecular FLP Synthon for PN2B‐Derived Heterocycles
Authors: LaFortune James H. W. , Trofimova Alina , Cummings Haley , Westcott Stephen A. , Stephan Douglas W.
Published: August 2019

Phosphinoboration of diazobenzene with Ph2PBR′2 cleanly affords products of the form Ph2P(PhNNPh)BR′2 (2: R′2=catechol, cat; 4: R′2=phenanthrenediol, quin) and shows evidence of Ph2P(PhNNPh)Bpin 7 (pin: pinacol). The mechanism of these reactions was probed computationally and shown to proceed via intermediates involving a diazobenzene‐adduct of the boron center of the PB reagent. The resulting PNNB species 2 and 4 are shown to be frustrated Lewis pairs (FLPs). Despite the presence of weakly Lewis acidic boron centers, these species react with diazobenzene. Additionally, the FLP reactivity of 2 was further probed with 4‐phenyl‐1,2,4‐triazole‐3,5‐dione, 1,10‐phenanthroline‐5,6‐dione, and benzyl azide to give unique five‐, six‐, and eight‐membered heterocyclic rings. Thus, phosphinoboration provides a new avenue to FLPs in which donor and acceptor sites are linked by nitrogen atoms.
Color effect of light sources on peridot based on CIE1976 L*a*b* color system and round RGB diagram system
Authors: Tang Jun , Guo Ying , Xu Chang
Published: August 2019

Previous research indicated that the peridot's color is dominated by the selective absorption of visible light caused by ferrous ion, the hue angle of which is in an inverse ratio of the concentration of Fe2+. This article focuses on the color effect of peridot under different standard light sources based on the CIE1976 L*a*b* color space system and round RGB diagram system and tries to find the best one for its grading and display. Based on the results of a series of experiments, including electron microprobe analysis, spectrophotometer, UV‐Vis spectrum, standard illumination box, and Munsell neutral color chips, it was suggested that the spectral power distribution and color temperature of a standard light source significantly influence the color of peridot in terms of lightness and chroma, particularly in the hue of peridot. As for color grading and displaying of peridot, standard light source A fails to fit in, and the color of peridot under a fluorescent light source has a higher chroma but a lower hue angle than that under daylight light source. The best choice for grading and displaying peridot is the standard light source D65. It is better to distinguish the hue of peridot when it is calculated by the round RGB diagram system.
Identification of the Polaron Measure I: Fixed Coupling Regime and the Central Limit Theorem for Large Times
Authors: Mukherjee Chiranjib , Varadhan S. R. S.
Published: August 2019

We consider the Fröhlich model of the polaron, whose path integral formulation leads to the transformed path measureurn:x-wiley:15347710:media:cpa21858:cpa21858-math-0001with respect to ℙ that governs the law of the increments of the three‐dimensional Brownian motion on a finite interval [−T, T], and Zα, T is the partition function or the normalizing constant and α > 0 is a constant, or the coupling parameter. The polaron measure reflects a self‐attractive interaction. According to a conjecture of Pekar that was proved in [9],
urn:x-wiley:15347710:media:cpa21858:cpa21858-math-0002
exists and has a variational formula. In this article we show that when α > 0 is either sufficiently small or sufficiently large, the limit exists, which is also identified explicitly. As a corollary, we deduce the central limit theorem for
urn:x-wiley:15347710:media:cpa21858:cpa21858-math-0003
under and obtain an expression for the limiting variance. © 2019 the Authors. Communications on Pure and Applied Mathematics is published by the Courant Institute of Mathematical Sciences and Wiley Periodicals, LLC.
Chiral Resolution of a Mn3+ Spin Crossover Complex
Authors: Jakobsen Vibe B. , O'Brien Luke , Novitchi Ghenadie , Müller‐Bunz Helge , Barra Anne‐Laure , Morgan Grace G.
Published: August 2019

Enantiopure Δ and Λ forms of the spin crossover Mn3+ chelate complex [Mn{5‐OCF3‐sal2(323)}]+ were prepared by co‐crystallization with the (R,R) and (S,S) forms of the chiral spiroborate anion bis[1,1′‐binaphthyl‐2,2′‐diolato]boron. The absolute structures of the enantiomers were established by X‐ray crystallography at 100 K and at 293 K. The enantiomeric purity of the Δ and Λ forms in acetonitrile solution was confirmed by circular dichroism spectroscopy in the UV/Vis range. Both enantiomers show a gradual and incomplete S = 1 ↔ S = 2 thermal spin crossover in the solid state but persist mainly in the spin triplet form between 3–200 K and retain a high percentage of spin triplet character at room temperature.
Aromatizative Inverse‐Electron‐Demand Hetero‐Diels‐Alder Reaction in the Synthesis of Benzothiophene Derivatives
Authors: Saktura Maciej , Joachim Bartłomiej , Grzelak Paulina , Albrecht Łukasz
Published: August 2019

An interesting inverse‐electron‐demand hetero‐Diels–Alder cycloaddition between azlactones and α,β‐unsaturated ketones derived from thioisatine has been developed. The reaction has been realized under basic conditions and benefits from its aromatizative character; the formation of benzothiophene moiety is the driving force of the cascade. An enantioselective variant of the cycloaddition has also been developed, with moderate enantioselectivities obtained.
Naproxen and Its Phototransformation Products: Persistence and Ecotoxicity to Toad Tadpoles (Anaxyrus terrestris), Individually and in Mixtures
Authors: Cory Wendy  C. , Welch Allison M. , Ramirez Jessica N. , Rein Luke C.
Published: August 2019

Although pharmaceutical pollution is a global environmental concern, much remains unknown about the transformation of pharmaceuticals in the wild and their effects on wildlife. In the environment, pharmaceuticals typically transform to some extent into different, structurally related compounds. Pharmaceutical transformation products resulting from exposure to sunlight (i.e., ultraviolet radiation) in surface waters are of particular concern; these products can be more hydrophobic, persistent, and toxic than their parent compounds. In the present study, naproxen, a widely used nonsteroidal anti-inflammatory drug, and its phototransformation products were studied to assess the overall persistence and photochemical fate of naproxen. Southern toad (Anaxyrus terrestris) larvae were used as model aquatic vertebrates to evaluate the acute toxicity of naproxen and its phototransformation products singly and in mixtures. The phototransformation products were observed to be more persistent and more toxic than naproxen itself. The slower phototransformation of the phototransformation products relative to naproxen suggests a greater potential to accumulate in the environment, particularly when naproxen is continually released. Mixtures of naproxen and its phototransformation products, in ratios observed during phototransformation, were more toxic than naproxen alone, as predicted by the model of concentration addition and the greater toxicity of the phototransformation products. Together, these results indicate that the ecological risk of naproxen may be underestimated by considering environmental levels of naproxen alone. Environ Toxicol Chem 2019;38:2008–2019. © 2019 SETAC.

Abstract

Phototransformation of naproxen generates transformation products of higher persistence and greater ecotoxicity to amphibian tadpoles. NAP-PT1 = 1-(6-methoxy-2-naphthyl)ethanol; NAP-PT2 = 2-acetyl-6-methoxynaphthalene.
The Toxicity of Nonaged and Aged Coated Silver Nanoparticles to Freshwater Alga Raphidocelis subcapitata
Authors: Lekamge Sam , Miranda Ana F. , Trestrail Charlene , Pham Ben , Ball Andrew S. , Shukla Ravi , Nugegoda Dayanthi
Published: August 2019

The transformation of coated silver nanoparticles (AgNPs) and their impacts on aquatic organisms require further study. The present study investigated the role of aging on the transformation of differently coated AgNPs and their sublethal effects on the freshwater alga Raphidocelis subcapitata. The stability of AgNPs was evaluated over 32 d, and the results indicated that transformation of AgNPs occurred during the incubation; however, coating-specific effects were observed. Fresh AgNPs increased reactive oxygen species (ROS) formation, whereas aged AgNPs induced excessive ROS generation compared with their fresh counterparts. Increased ROS levels caused increased lipid peroxidation (LPO) in treatment groups exposed to both fresh and aged NPs, although LPO was comparatively higher in algae exposed to aged AgNPs. The observed increase in catalase (CAT) activity of algal cells was attributed to early stress responses induced by excessive intracellular ROS generation, and CAT levels were higher in the aged NP treatment groups. In conclusion, AgNPs increased ROS levels and LPO in algae and caused the activation of antioxidant enzymes such as CAT. Overall, the results suggest that aging and coating of AgNPs have major impacts on AgNP transformation in media and their effects on algae. Environ Toxicol Chem 2019;38:2371–2382. © 2019 SETAC
Effects of grape pomace and seed polyphenol extracts on the recovery of gut microbiota after antibiotic treatment in high‐fat diet‐fed mice
Authors: Lu Feng , Liu Fengjiao , Zhou Qian , Hu Xiaosong , Zhang Yan
Published: August 2019

The widespread use of antibiotics all over the world increases the risk of many metabolic diseases by altering the gut microbiota. Grape by‐products are of particular interest in the prevention of metabolic diseases, while only minimum amounts of these wastes are up‐graded or recycled at present. The study investigated the effect of grape pomace (GPE) and seed (GSE) polyphenol extracts on the recovery of gut microbiota after antibiotic cocktail treatment in high‐fat diet‐fed (HFD) mice. C57BL/6J mice were fed HFD together with antibiotic treatment by drinking water for 3 weeks. Then, GPE and GSE were supplemented for 7 days after withdrawal of antibiotics. The gut microbiota was characterized by a significant loss of diversity and certain important taxon after a 3‐week antibiotic cocktail treatment. The GPE and GSE supplementation during the restore period of gut microbiota had some positive effects. The relative abundance of gut microbiota was improved by GPE and GSE compared to the spontaneous recovery group. And gut microbiota diversity was also greatly changed by GPE and GSE, being indicated by the changes of Verrucomicrobia and Akkermansia in feces. These findings suggested that grape polyphenol extracts have a great influence on the recovery of gut microbiota after antibiotics and high‐fat diet treatment.
Volatile components and nutritional qualities of Viscum articulatum Burm.f. parasitic on ancient tea trees
Authors: Wang Qiushuang , Chen Dong , Zhang Qianwen , Qin Dandan , Jiang Xiaohui , Li Hongjian , Fang Kaixing , Cao Junxi , Wu Hualing
Published: August 2019

Volatile flavor compounds (VFCs) and nutrients in Viscum articulatum Burm.f. parasitic on ancient tea trees (named TM) were studied in this research by headspace solid‐phase microextraction (HS‐SPME)/gas chromatography–mass spectrometry (GC–MS) and conventional methods. Sixty‐six volatile compounds belonging to different classes were identified by GC–MS. The ketones, alcohols, and aldehydes were the principal aroma groups in TM according to principle component analysis (PCA). The most abundant aroma components in TM included benzaldehyde (9.64%), geranylacetone (7.92%), epoxy‐β‐ionone (7.71%), β‐linalool (7.35%), methyl salicylate (6.96%), and hotrienol (6.14%), significantly higher than CKs (p < .05). The positive PC1 and PC2 in TM were correlated with benzaldehyde, hotrienol, methyl salicylate, and geranylacetone. The mistletoes could be differentiated from CKs due to the difference in aroma compounds. Clean and fresh, woody and nutty odor with minor floral scent was the characteristics of TM. Analysis of the nutritional components showed that contents of polyphenols and catechins in TM were at trace levels, significantly lower than CKs (p < .05). The total contents of polyphenols, amino acids, carbohydrates, and caffeine in TM were significantly lower from the total soluble solids (p < .05), indicating that there were still lots of compounds undetected in TM. The sensory test showed that the taste and aroma in TM can be accepted, which indicates TM could be developed into alternative tea drinks in the future.
Neoarchaean subduction tectonics in Western Shandong Province, China: Evidence from geochemistry and zircon U–Pb–Hf isotopes of metabasalts
Authors: Yang Lihui , Hou Guiting , Gao Lei , Liu Shuwen
Published: August 2019

Neoarchaean supracrustal rocks, which were discovered in the Longhuzhai and Menglianggu areas of the Western Shandong Province (WSP) in the Eastern Block of the North China Craton (NCC), are fine‐ to medium‐grained amphibolites that commonly underwent greenschist‐ to amphibolite‐facies metamorphism. LA‐ICP‐MS zircon U–Pb analyses revealed that these metabasalts erupted at 2,527 ± 5 to 2,514 ± 4 Ma. These supracrustal rocks are tholeiitic basalts in chemical composition and exhibit relatively high SiO2 (49.30–53.34 wt%) and MgO (5.24–11.82 wt%) contents but low TiO2 (0.41–0.75 wt%) contents. They display flat chondrite‐normalized rare earth element (REE) patterns ((La/Yb)N = 1.21–2.60) and negative Nb, Ta, and Ti anomalies ((Nb/La)PM = 0.16–0.54), which are similar to those of typical island arc tholeiites (IATs) in subduction‐related settings. These findings, combined with the positive zircon εHf(t) values (+2.51 to +8.90) and εNd(t) values (+0.19 to +3.65), suggest that these metabasalts were derived from the partial melting of a depleted mantle source that was metasomatized by slab‐derived fluids at shallow levels in the upper mantle. Accordingly, the development of arc‐related tholeiitic volcanic rocks within the interior of the WSP imply that the Neoarchaean (2.6–2.5 Ga) subduction‐related slab–wedge interaction mechanism was widespread in the WSP and played a crucial role in the formation of the continental crust and its growth.
Automated brain extraction of multisequence MRI using artificial neural networks
Authors: Isensee Fabian , Schell Marianne , Pflueger Irada , Brugnara Gianluca , Bonekamp David , Neuberger Ulf , Wick Antje , Schlemmer Heinz‐Peter , Heiland Sabine , Wick Wolfgang , Bendszus Martin , Maier‐Hein Klaus H. , Kickingereder Philipp
Published: August 2019

Brain extraction is a critical preprocessing step in the analysis of neuroimaging studies conducted with magnetic resonance imaging (MRI) and influences the accuracy of downstream analyses. The majority of brain extraction algorithms are, however, optimized for processing healthy brains and thus frequently fail in the presence of pathologically altered brain or when applied to heterogeneous MRI datasets. Here we introduce a new, rigorously validated algorithm (termed HD‐BET) relying on artificial neural networks that aim to overcome these limitations. We demonstrate that HD‐BET outperforms six popular, publicly available brain extraction algorithms in several large‐scale neuroimaging datasets, including one from a prospective multicentric trial in neuro‐oncology, yielding state‐of‐the‐art performance with median improvements of +1.16 to +2.50 points for the Dice coefficient and −0.66 to −2.51 mm for the Hausdorff distance. Importantly, the HD‐BET algorithm, which shows robust performance in the presence of pathology or treatment‐induced tissue alterations, is applicable to a broad range of MRI sequence types and is not influenced by variations in MRI hardware and acquisition parameters encountered in both research and clinical practice. For broader accessibility, the HD‐BET prediction algorithm is made freely available (www.neuroAI-HD.org) and may become an essential component for robust, automated, high‐throughput processing of MRI neuroimaging data.
MP2RAGE multispectral voxel‐based morphometry in focal epilepsy
Authors: Kotikalapudi Raviteja , Martin Pascal , Erb Michael , Scheffler Klaus , Marquetand Justus , Bender Benjamin , Focke Niels K.
Published: August 2019

We assessed the applicability of MP2RAGE for voxel‐based morphometry. To this end, we analyzed its brain tissue segmentation characteristics in healthy subjects and the potential for detecting focal epileptogenic lesions (previously visible and nonvisible). Automated results and expert visual interpretations were compared with conventional VBM variants (i.e., T1 and T1 + FLAIR). Thirty‐one healthy controls and 21 patients with focal epilepsy were recruited. 3D T1‐, T2‐FLAIR, and MP2RAGE images (consisting of INV1, INV2, and MP2 maps) were acquired on a 3T MRI. The effects of brain tissue segmentation and lesion detection rates were analyzed among single‐ and multispectral VBM variants. MP2‐single‐contrast gave better delineation of deep, subcortical nuclei but was prone to misclassification of dura/vessels as gray matter, even more than conventional‐T1. The addition of multispectral combinations (INV1, INV2, or FLAIR) could markedly reduce such misclassifications. MP2 + INV1 yielded generally clearer gray matter segmentation allowing better differentiation of white matter and neighboring gyri. Different models detected known lesions with a sensitivity between 60 and 100%. In non lesional cases, MP2 + INV1 was found to be best with a concordant rate of 37.5%, specificity of 51.6% and concordant to discordant ratio of 0.60. In summary, we show that multispectral MP2RAGE VBM (e.g., MP2 + INV1, MP2 + INV2) can improve brain tissue segmentation and lesion detection in epilepsy.
How are visual words represented? Insights from EEG‐based visual word decoding, feature derivation and image reconstruction
Authors: Ling Shouyu , Lee Andy C. H. , Armstrong Blair C. , Nestor Adrian
Published: August 2019

Investigations into the neural basis of reading have shed light on the cortical locus and the functional role of visual‐orthographic processing. Yet, the fine‐grained structure of neural representations subserving reading remains to be clarified. Here, we capitalize on the spatiotemporal structure of electroencephalography (EEG) data to examine if and how EEG patterns can serve to decode and reconstruct the internal representation of visually presented words in healthy adults. Our results show that word classification and image reconstruction were accurate well above chance, that their temporal profile exhibited an early onset, soon after 100 ms, and peaked around 170 ms. Further, reconstruction results were well explained by a combination of visual‐orthographic word properties. Last, systematic individual differences were detected in orthographic representations across participants. Collectively, our results establish the feasibility of EEG‐based word decoding and image reconstruction. More generally, they help to elucidate the specific features, dynamics, and neurocomputational principles underlying word recognition.
Pilot competencies as components of a dynamic human‐machine system
Authors: Mansikka Heikki , Harris Don , Virtanen Kai
Published: August 2019

This paper formulates a theoretical model of flight deck team performance as a dynamic human‐machine system, later referred to as CRM‐DYMO (Crew Resources Management‐DYnamic MOdel). The model identifies human and machine subsystems. The human subsystem describes the activities taken by the flight crew and the machine subsystem describes the changes in the aircraft's state. The human subsystem's output forms an input for the machine subsystem, and the machine subsystem's output feeds back to the human system creating a closed loop system. Pilots’ performance are described as competencies, which form part of the elements in the human subsystem. This paper concentrates only on CRM competencies as defined by the International Civil Aviation Authority and the International Air Transport Association. In addition to the detailed conceptual model of the human subsystem and associated competencies, the approach is illustrated with reference to two accident case studies. These demonstrate how CRM‐DYMO can assist in analyzing CRM and help in identifying how the different system components interact. Although the case studies demonstrate the benefits of CRM‐DYMO, they merely serve as a starting point to understand how CRM works and will hopefully encourage supporting quantitative simulation modeling and empirical studies.
Hsa‐miR‐139‐5p is a prognostic thyroid cancer marker involved in HNRNPF‐mediated alternative splicing
Authors: Montero‐Conde Cristina , Graña‐Castro Osvaldo , Martín‐Serrano Guillermo , Martínez‐Montes Ángel M. , Zarzuela Eduardo , Muñoz Javier , Torres‐Perez Rafael , Pita Guillermo , Cordero‐Barreal Alfonso , Leandro‐García Luis J. , Letón Rocío , López de Silanes Isabel , Guadalix Sonsoles , Pérez‐Barrios Andrés , Hawkins Federico , Guerrero‐Álvarez Almudena , Álvarez‐Escolá Cristina , Regojo‐Zapata Rita M. , Calsina Bruna , Remacha Laura , Roldán‐Romero Juan M. , Santos María , Lanillos Javier , Jordá Mireia , Riesco‐Eizaguirre Garcilaso , Zafon Carles , González‐Neira Anna , Blasco Maria A. , Al‐Shahrour Fátima , Rodríguez‐Antona Cristina , Cascón Alberto , Robledo Mercedes
Published: August 2019

It is critical to identify biomarkers and functional networks associated with aggressive thyroid cancer to anticipate disease progression and facilitate personalized patient management. We performed miRNome sequencing of 46 thyroid tumors enriched with advanced disease patients with a median follow‐up of 96 months. MiRNome profiles correlated with tumor‐specific histopathological and molecular features, such as stromal cell infiltration and tumor driver mutation. Differential expression analysis revealed a consistent hsa‐miR‐139‐5p downexpression in primary carcinomas from patients with recurrent/metastatic disease compared to disease‐free patients, sustained in paired local metastases and validated in publicly available thyroid cancer series. Exogenous expression of hsa‐miR‐139‐5p significantly reduced migration and proliferation of anaplastic thyroid cancer cells. Proteomic analysis indicated RICTOR, SMAD2/3 and HNRNPF as putative hsa‐miR‐139‐5p targets in our cell system. Abundance of HNRNPF mRNA, encoding an alternative splicing factor involved in cryptic exon inclusion/exclusion, inversely correlated with hsa‐miR‐139‐5p expression in human tumors. RNA sequencing analysis revealed 174 splicing events differentially regulated upon HNRNPF repression in our cell system, affecting genes involved in RTK/RAS/MAPK and PI3K/AKT/MTOR signaling cascades among others. These results point at the hsa‐miR‐139‐5p/HNRNPF axis as a novel regulatory mechanism associated with the modulation of major thyroid cancer signaling pathways and tumor virulence.
Revisiting the African origins of attachment research—50 years on from Ainsworth: A descriptive review
Authors: Voges Juané , Berg Astrid , Niehaus Dana J.H.
Published: August 2019

Culture plays a significant role in the variations observed in the manifestation, expression, and meaning of attachment behaviors. Africa is home to multiple cultures, with distinct organizations of caregiving relationships underlying the development of attachment. This review aims to consolidate knowledge about African attachment by describing studies of infant attachment conducted in Africa since Mary Ainsworth's Ugandan findings in 1967. Electronic databases were searched with the terms “Africa” (“attachment” or “bond”) and “infant.” Nine studies that assessed infant attachment style with self‐report or observation methods were included, but spanned only five countries. The Strange Situation Procedure was most frequently used. Most studies described dyads living in peri‐urban or township areas. Multiple socioeconomic factors affecting living conditions were identified, including, unemployment, financial difficulties, limited education, poor housing, single parenthood, lack of partner support, substance abuse, and depression. Overall distributions of attachment classification proportions appear consistent with global attachment‐classification patterns. Despite adverse conditions, secure attachment was relatively widespread, and some populations had low rates of avoidant attachment. Relatively high rates of disorganized attachment were found when the category was included. Africa remains an understudied continent regarding infant attachment. The continent's cultural diversity may hold important truths necessary for understanding the complex relationship between infant and attachment figure.