bluuebunny/crossref_metadata_2025 huggingface dataset:
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‐Ray Emission Spectroscopic Techniques in Bioinorganic Applications
Authors: DeBeer Serena , Bergmann Uwe
Published: September 2016

Hard X‐ray core hole spectroscopy plays an important role in countless areas of research including chemistry, physics, biology, materials science, medicine, geoscience, and even natural and cultural heritage. The main attraction of these methods lies in the atomic level structural and chemical information, the elemental selectivity, and the practical advantages related to the penetration power of hard X‐rays, allowing for a wide range of samples and sample environments. Powerful synchrotron sources with intense, tunable, and highly collimated X‐ray beams have pushed the detection limit for X‐ray spectroscopy to minute elemental concentrations, including the active sites in dilute metalloproteins. Much of the focus over the past 40 years has been on X‐ray absorption spectroscopy (XAS) methods including X‐ray absorption near edge structure (XANES) and extended range X‐ray absorption fine structure (EXAFS) spectroscopy. More recently, there has been an increasing activity in X‐ray emission spectroscopy (XES) and other high‐resolution photon‐out techniques such as X‐ray Raman scattering. These efforts have been aided by the development of efficient, dedicated, high‐resolution photon‐out X‐ray spectrometers that are now routinely used at many synchrotron facilities. XES provides information on the local atomic and electronic structure that is complementary to X‐ray scattering and diffraction methods and XAS. We will discuss various XES techniques and their specific benefits and limitations regarding studies in bioinorganic chemistry and describe examples of recent results. We will present the basic information regarding the required instrumentation, discuss the various approaches, and give a comprehensive instrumentation literature review.

With the advent of X‐ray free electron lasers (XFELs), fourth‐generation synchrotron light sources that are many orders of magnitude brighter than storage rings, revolutionary new capabilities for the studies of many materials on times scales down to femtoseconds have become available. Owing to the stochastic nature of the XFEL pulses, XES techniques, where the whole spectrum is collected in a shot‐by‐shot manner, are specifically attractive and have been the predominant choice of the early XFEL‐based X‐ray spectroscopy work. We will discuss this work and the related instrumentation from the perspective of the bioinorganic field. We conclude with a few thoughts on potential future XES techniques, which take advantage of nonlinear processes that result from the interaction of very intense XFEL pulses with matter.
Photocatalytic Production of Hydrogen with Earth‐Abundant Metal Catalysts
Authors: Fukuzumi Shunichi , Yamada Yusuke
Published: September 2016

Photocatalytic production of hydrogen occurs by combination of model compounds of the photosynthetic reaction center with organic photocatalysts and earth‐abundant metal nanoparticles as proton reduction catalysts and with visible light irradiation of an acetonitrile–water mixture solvent containing a sacrificial electron donor. Mesoporous silica–alumina was utilized to incorporate organic photocatalysts and earth‐abundant metal nanoparticles together as composite catalysts in an aqueous solution. Earth‐abundant metal nanoparticles were produced
in situ
by the photoreduction of metal salts with oxalate anion in mesoporous silica–alumina. The photocatalytic hydrogen evolution with nicotinamide adenine dinucleotide (NADH) was enhanced by a synergistic effect of Ni and Cu supported on TiO
2
and SiO
2
. Such a synergistic effect among base metals and metal oxides provides a promising strategy to develop active catalysts for hydrogen evolution without using platinum group metals.
Ionic Liquids: Enzymatic Hydrolysis of Lignocellulose
Authors: Wahlström Ronny M. , Suurnäkki Anna K.
Published: September 2016

Lignocellulose is an abundant and renewable resource with potential to replace fossil raw materials. The general recalcitrance of lignocellulose makes it difficult to depolymerize plant cell wall polysaccharides to fermentable monosaccharides. Thus, efficient pretreatments are needed prior to polysaccharide hydrolysis, which, in current second generation bioethanol plants, is done by enzymatic hydrolysis. Ionic liquids (ILs) are salts with low melting points (<100 °C) and some ILs have been found to dissolve cellulose or even lignocellulose. It has been shown that different pretreatments with ILs, in which the whole lignocellulose sample, or components of it, are dissolved, lead to significantly increased enzymatic hydrolysis yields and kinetics. After IL pretreatment, the substrate is typically washed, but the washing is a very water‐intensive process. To skip process steps and improve water economy, a one‐pot procedure has been proposed, in which the IL pretreatment and enzymatic hydrolysis of lignocellulose are done subsequently in the same vessel without the intermediary step of IL removal.

Cellulose‐dissolving ILs inactivate cellulases and hemicellulases, the enzymes used in plant cell wall polysaccharide hydrolysis. This fact severely limits the applicability of the one‐pot hydrolysis procedure. The inactivation mechanisms of cellulases in ILs have not been fully elucidated so far, but proposed reasons for inactivation include structural unfolding, stripping of essential water molecules, reduced substrate‐binding affinity, competitive inhibition, and pH effects due to the basicity of cellulose‐dissolving ILs. In order to overcome cellulase inactivation in the presence of IL, several strategies have been tested. Cellulose‐dissolving ILs have been designed with special focus on features to ensure better enzyme compatibility. Enzymes with better IL tolerance have been screened from metagenomic libraries and organisms living in extreme environments, or enzyme IL tolerance has been improved by different directed evolution endeavors, mutagenesis or point mutation approaches. In addition, chemical modification of protein surfaces and immobilization have been reported as effective methods to increase enzyme IL tolerance. Impressive progress has been made in the area with several different approaches for providing enzyme‐compatible hydrolysis mixtures in the presence of even high IL concentrations.
Sustainable Biosurfactants
Authors: Bajpai Tripathy Divya , Mishra Anuradha
Published: September 2016

Biosurfactants or microbial surfactants are a diverse group of nonconventional surface active substances synthesized from microorganisms such as bacteria, fungi, and yeast. The hydrophilic moiety of biosurfactants can either be an amino acid, peptide group, phosphate group, carbohydrate (mono‐, di‐, or polysaccharides), or some other compounds, whereas the hydrophobic group is generally made up of long hydrocarbon tail. Commonly, biosurfactants are neutral or anionic in nature. On the basis of their mass, they are broadly classified in two categories namely low‐ and high‐mass biosurfactants. Glycolipids, phospholipids, lipopeptides, lipoproteins, and neutral lipids are low‐mass biosurfactants, whereas polymeric and particulate biosurfactants are high‐mass biosurfactants. Some commonly known examples of biosurfactants are surfactin produced fromBacillus subtilis, rhamnolipids produced fromPseudomonas aeruginosa, emulsan produced fromAcinetobacter calcoaceticus, and sophorolipids produced fromCandida bombicola. The nature of carbon and nitrogen sources, pH, temperature, and agitation are usually the factors that influence the production of biosurfactants. Their varied surface active properties such as excellent ability to lower the surface tension and interfacial tension, low CMC (critical micelle concentration) values, emulsification and de‐emulsification, HLB (hydrophilic–lipophilic balance), and better pH and thermal stability are due to their specific structure. Low or no toxicity, fast biodegradation, and specific structural properties of biosurfactants label them as green and sustainable materials. These properties make them superior over chemically synthesized counterparts and stimulate the interest of researchers and industry for their extensive use. Their easy dispersability, emulsifying and de‐emulsifying property, good wettability, and corrosion inhibition property are exploited in many industries such as detergent, agriculture, laundry, polymer, pharmaceuticals, cosmetics, food, and in microbial enhanced oil recovery. Despite having a large number of advantages, a few disadvantages are also linked with biosurfactants/microbial surfactants. The two most specific disadvantages are their production cost and purification. Biotechnological processes involved in the synthesis of biosurfactants are pretty expensive, and purification of surfactants is a bit problematic. Various research groups are working especially for the cost cutting of biosurfactants' production by using easily available and renewable bioresources as raw materials for the production of biosurfactants.

Use of biosurfactants at commercial level is the need of the hour to reduce of the harmful effects of conventional synthetic surfactants on environment. Disadvantages associated with them are to be surmounted by the scientists. Full potential of these sustainable versatile surfactants may be achieved by the economic balance between their production cost and benefits.
Multifunctional
MOF
‐Based Photocatalysis
Authors: Sun Dengrong , Li Zhaohui
Published: September 2016

The ever‐increasing global demand for energy has stimulated a new wave of research activities on efficient solar energy utilization. Photocatalysis is a promising pathway in the direct transformation of solar energy to chemical energy. Metal–organic frameworks (MOFs), a new class of porous crystalline materials, have emerged as intriguing photocatalytic materials owing to their unique structure properties such as high surface area, tunable but uniform cavities, and tailorable chemistry. In this chapter, we summarize the recent development of the applications of MOFs in photocatalysis, including hydrogen evolution, CO
2
reduction, organic transformations, and environmental remediation, in which MOFs act as photocatalysts, cocatalysts, or supports for homogeneous photoactive complexes. At the end of this chapter, personal perspectives on the opportunities and limitations of using MOFs in photocatalysis are also shared.
Unanimous versus partial rejection: How the number of excluders influences the impact of ostracism in children
Authors: Sandstrom Marlene J. , Deutz Marike H. F. , Lansu Tessa A. M. , van Noorden Tirza H. J. , Karremans Johan C. , Cillessen Antonius H. N.
Published: September 2016

Previous research has shown that ostracism—the experience of being ignored and excluded—has negative effects on all of us, young and old. Using a Cyberball paradigm, the present research replicates the effects of ostracism on the moods (anger, anxiety, happiness, and anger) and fundamental needs (belongingness, control, meaningful existence, and self‐esteem) of children (Study 1) and then extends the literature by examining the role of the number of ostracizers and inclusive members in this process by randomly assigning children to conditions varying in degree of ostracism (Study 2). Results of both studies showed that experiencing ostracism strongly and negatively affected all moods and fundamental needs—with the exception of anxiety. Study 2 in addition showed that the ratio of excluders to inclusive group members had different effects across outcomes. In all cases, complete ostracism produced the worst outcomes, suggesting that the presence of even a single ally reduces children's distress. For sadness, unanimous ostracism seemed particularly toxic. In some cases, facing two ostracizers produced significantly worse outcomes than only one, suggesting that consensual rejection might drive the negative effects on happiness, and sense of belonging, control, and meaningful existence. For self‐esteem, only one ostracizer (in the presence of two inclusive members) was sufficient to induce a negative effect. Aggr. Behav. 43:190–203, 2017. © 2016 Wiley Periodicals, Inc.
High‐κ Solid‐Gate Transistor Configured Graphene Biosensor with Fully Integrated Structure and Enhanced Sensitivity
Authors: Wang Cheng , Li Yijun , Zhu Yibo , Zhou Xiaohong , Lin Qiao , He Miao
Published: September 2016

A fully integrated graphene field‐effect transistor (GFET) nanosensor utilizing a novel high‐κ solid‐gating geometry for a practical biosensor with enhanced sensitivity is presented. Herein, an “in plane” gate supplying electrical field through a 30 nm HfO2 dielectric layer is employed to eliminate the cumbrous external wire electrode in conventional liquid‐gate GFET nanosensors that undesirably limits the device potential in on‐site sensing applications. In addition to the advantage in the device integration degree, the transconductance level is found to be increased by about 50% over liquid‐gate GFET devices in aqueous‐media, thereby improves the sensitivity performance in sensor applications. As the first demonstration of biosensing applications, a small‐molecule antibiotic, kanamycin A, is detected by means of an aptameric competitive affinity principle. It is experimentally shown that the label‐free and specific quantification of kanamycin A with a concentration resolution at 11.5 × 10−9
m is achievable through a single direct observation of the 200 s fast bioassay without any further noise canceling. These results demonstrate the utility and practicability of the new devices in label‐free biosensing as a novel analytical tool, and potentially hold great promise in other significant biomedical applications.
Wettability of Supported Monolayer Hexagonal Boron Nitride in Air
Authors: Li Xuemei , Qiu Hu , Liu Xiaofei , Yin Jun , Guo Wanlin
Published: September 2016

Hexagonal boron nitride (h‐BN), a wide band gap monolayer crystal with structure similar to graphene, is optically transparent with exceptionally high thermal and chemical stability, and should be ideal to serve as an atomically thin coating. However, limited by the challenges in fabricating h‐BN of high quality in large area, the wetting performance of h‐BN has seldom been studied. Here, it is shown that the water contact angle of freshly grown h‐BN film is nearly independent of the underlying materials as well as the h‐BN layer number, but increases gradually to a saturated stable value in air due to the spontaneous adsorption of airborne hydrocarbon. First‐principles calculations and molecular interaction modeling confirm that a monolayer h‐BN coating does efficiently tune the interaction of a water molecule with different substrates to a converging level. The saturated wettability of h‐BN coating is robust against variation of several factors, facilitating its practical applications.
In Situ Environmental TEM in Imaging Gas and Liquid Phase Chemical Reactions for Materials Research
Authors: Wu Jianbo , Shan Hao , Chen Wenlong , Gu Xin , Tao Peng , Song Chengyi , Shang Wen , Deng Tao
Published: September 2016

Gas and liquid phase chemical reactions cover a broad range of research areas in materials science and engineering, including the synthesis of nanomaterials and application of nanomaterials, for example, in the areas of sensing, energy storage and conversion, catalysis, and bio‐related applications. Environmental transmission electron microscopy (ETEM) provides a unique opportunity for monitoring gas and liquid phase reactions because it enables the observation of those reactions at the ultra‐high spatial resolution, which is not achievable through other techniques. Here, the fundamental science and technology developments of gas and liquid phase TEM that facilitate the mechanistic study of the gas and liquid phase chemical reactions are discussed. Combined with other characterization tools integrated in TEM, unprecedented material behaviors and reaction mechanisms are observed through the use of the in situ gas and liquid phase TEM. These observations and also the recent applications in this emerging area are described. The current challenges in the imaging process are also discussed, including the imaging speed, imaging resolution, and data management.
An Integrated Paper‐Based Readout System and Piezoresistive Pressure Sensor for Measuring Bandage Compression
Authors: Liana Devi D. , Raguse Burkhard , Gooding J. Justin , Chow Edith
Published: September 2016

The treatment of venous leg ulcers is commonly performed through the use of compression bandaging. However, applying an effective pressure can be a challenge, even for an experienced nurse. In this work, a simple and portable integrated platform consisting of a piezoresistive pressure sensor, paper‐based electrochromic readout system and battery is developed to directly monitor the applied pressure. The pressure sensor is fabricated using a mixture of copper particles and polydimethylsiloxane and tuned to the desired pressure sensitivity via the addition of carbon paste. Since the sensor is to be incorporated within the bandage, an external electronic display is not practical and thus a lightweight, paper‐based readout system comprising an electrochromic coating of Prussian blue/polyaniline on top of segments of gold nanoparticle films connected via graphite resistive films is developed. The readout system functions by measuring changes in the voltage drop across the readout system due to changes in the resistance of the pressure sensor. This allows the applied pressure to be visualized by the number of gold nanoparticle segments that have changed color in the readout system. This work opens the door to a lightweight and low‐cost sensing approach for compression bandaging at home or in community locations.
Friedel–Crafts Reaction of Indoles with Isatin‐Derived β,γ‐Unsaturated α‐Keto Esters Using a BINOL‐Derived Bisoxazoline (BOX)/Copper(II) Complex as Catalyst
Authors: Li Nai‐Kai , Kong Ling‐Pei , Qi Zheng‐Hang , Yin Shao‐Jie , Zhang Jun‐Qi , Wu Bing , Wang Xing‐Wang
Published: September 2016

Several chiral BINOL‐derived bisoxazoline (BOX)/copper(II) complexes were synthesized and evaluated as catalysts for the Friedel–Crafts reaction of indoles with isatin‐derived β,γ‐unsaturated α‐keto esters. The resulting bis‐indole products bearing a quaternary stereocenter were obtained in excellent yields and enantioselectivities. Additionally, the desired products were practically transformed to α‐amino esters, α‐hydroxy esters and α‐keto amides. It is noteworthy that this catalytic procedure was conducted with a catalyst loading of 0.5 mol% without any discernible decrease in the reactivity or enantioselectivity.

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Olefin Metathesis of Vinylgermanium Derivatives as Method for the Synthesis of Functionalized Cubic and Double‐Decker Germasilsesquioxanes
Authors: Żak Patrycja , Frąckowiak Dawid , Grzelak Magdalena , Bołt Małgorzata , Kubicki Maciej , Marciniec Bogdan
Published: September 2016

For the first time, olefin cross metathesis has been developed for vinylgermanium compounds. This paper also marks the first case of transition metal‐catalyzed functionalization of heterosilsesquioxanes, which in our case are cubic vinylgermasilsesquioxanes and newly synthesized di(vinylgermyl)substituted double‐decker silsesquioxane. These processes lead to a series of new molecular, unsaturated mono‐ and divinyl‐substituted germasilsesquioxanes, which can be potentially applied as precursors for optoelectronics and for the synthesis of new advanced materials. Additionally, preliminary tests of metathetic copolymerization of divinylsubstituted double‐decker digermasilsesquioxanes (DDSQ‐2ViGe) with selected diolefins proved to be very promising and resulted in the synthesis of novel stereoregular trans‐germasilsesquioxyl‐vinylene‐phenylene macromolecular derivatives. All newly obtained compounds were isolated and characterized by mass and spectroscopic methods.

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Copper‐Catalyzed Trifluoromethylation and Bicyclizations of 1,7‐Enynes Leading to Fused Polycycles
Authors: Wang Qiang , Song Hongjian , Liu Yuxiu , Song Haibin , Wang Qingmin
Published: September 2016

A series of trifluoromethyl‐containing heterocycles, like indene and dihydroquinolinone or dihydrocoumarin‐fused tetracyclic compounds have been prepared using copper‐catalyzed cascade reaction of benzene‐tethered 1,7‐enynes. A study of the mechanism indicated that radical trifluoromethylation and sequential 6‐exo‐dig/5‐endo‐trig bicyclization processes were involved in this protocol. Moreover, some selected products showed certain fungicidal activities against 14 kinds of plant fungi which means that these functionalized tetracyclic compounds might be used in the agrochemical field.

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Enantioselective Construction of Cyclic Enaminone‐Based 3‐Substituted 3‐Amino‐2‐oxindole Scaffolds via Catalytic Asymmetric Additions of Isatin‐Derived Imines
Authors: Zhou Lu‐Jia , Zhang Yu‐Chen , Jiang Fei , He Guofeng , Yan Jingjing , Lu Han , Zhang Shu , Shi Feng
Published: September 2016

The first catalytic asymmetric construction of the cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindole scaffold with potential bioactivity has been developed via chiral phosphoric acid‐catalyzed enantioselective addition reactions of cyclic enaminones to isatin‐derived imines, which afforded a series of cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindoles in high yields and excellent enantioselectivities (up to 99% yield, 97% ee). The investigation of the reaction mechanism suggested that it was facilitated by a dual hydrogen‐bonding activation mode between the two substrates and the chiral phosphoric acid. Besides, this method could be utilized for a large‐scale synthesis with maintained enantioselectivity. This approach will not only offer a useful method for enantioselective construction of the cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindole scaffold, but also enrich the research on catalytic asymmetric addition reactions of isatin‐derived imines by using electron‐rich olefins as nucleophiles. More importantly, a preliminary evaluation on the cytotoxicity of some selected products revealed that two of the enantio‐pure compounds exhibited moderate to strong cytotoxicity to A549, 786‐0, ECA109 and BT474 cancer cell lines.

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Facile, Efficient and Diastereoselective Construction of Indane‐Fused Pyrrolidin‐2‐ones via a Potassium Hydroxide‐Catalyzed Domino Reaction
Authors: Xing Siyang , Ren Jing , Wang Kui , Cui Hong , Xia Tian , Zhang Ming , Wang Dandan
Published: September 2016

A facile and efficient potassium hydroxide (KOH)‐catalyzed tandem reaction involving sequential Michael addition of electron‐deficient alkenes with malonic esters, ring opening of activated aziridines and lactamization has been described. A highly functionalized indane‐fused tricyclic scaffold containing three rings, three adjacent stereocenters and a quaternary center was constructed by the formation of two new C–C bonds and one new C–N bond in a diastereoselective manner.

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Distribution and Neighborhood Correlates of Sober Living House Locations in Los Angeles
Authors: Mericle Amy A. , Karriker‐Jaffe Katherine J. , Gupta Shalika , Sheridan David M. , Polcin Doug L.
Published: September 2016

Sober living houses (SLHs) are alcohol and drug‐free living environments for individuals in recovery. The goal of this study was to map the distribution ofSLHs in Los Angeles (LA) County, California (N = 260) and examine neighborhood correlates ofSLHdensity. Locations ofSLHs were geocoded and linked to tract‐level Census data as well as to publicly available information on alcohol outlets and recovery resources. Neighborhoods withSLHs differed from neighborhoods without them on measures of socioeconomic disadvantage and accessibility of recovery resources. In multivariate, spatially lagged hurdle models stratified by monthly fees charged (less than $1400/month vs. $1400/month or greater), minority composition, and accessibility of treatment were associated with the presence of affordableSLHs. Accessibility of treatment was also associated with the number of affordableSLHs in those neighborhoods. Higher median housing value and accessibility of treatment were associated with whether a neighborhood had high‐costSLHs, and lower population density was associated with the number of high‐costSLHs in those neighborhoods. Neighborhood factors are associated with the availability ofSLHs, and research is needed to better understand how these factors affect resident outcomes, as well as howSLHs may affect neighborhoods over time.
Exploring imperial expansion using an isotopic analysis of paleodietary and paleomobility indicators in Chachapoyas, Peru
Authors: Toyne J. Marla , Church Warren B. , Luis Coronado Tello Jose , Morales Gamarra Ricardo
Published: September 2016

Objectives

Inca imperial strategies of political and territorial expansion varied across conquered regions depending on local ecology and cultural resistance, and Chachapoya peoples in Peru's forested northeastern Andes were renowned for their rebellions against the invaders. The cliff tombs of Los Pinchudos (AD 1470–1535) present opportunities to use stable isotopes to: (1) explore dietary and mobility patterns from a mortuary community interred at a site attributed to the poorly‐known Chachapoya culture during the period of Inca domination, and (2) explore the origins of the individuals as either local or foreign (Inca). Using biochemical tracers, we can help resolve the impact of foreign influence and changes in population and social structure during imperial occupation.

Materials and Methods

While it is difficult to reconstruct individual life histories from incomplete skeletons, stable isotopic analysis of multiple skeletal tissues provides a direct means of characterizing diet and residential mobility. Values of stable carbon (δ13C), nitrogen (δ15N), and oxygen isotope (δ18O) ratios were determined in bone and dentine collagen and bone and enamel carbonate from 28 samples (11 paired tissues) from males, females, and juveniles from Los Pinchudos.

Results

Dietary signatures are consistent with a mixed but more C3‐based plant and protein‐based diet with moderate proportions of terrestrial animals. Oxygen isotopic values demonstrate limited variation between paired tissues, with a few possible nonlocal individuals buried in one particular tomb at the site. Compared to other Andean areas that underwent imperial domination, these data do not demonstrate expected dietary shifts.

Discussion

These are the first isotopic data from a Chachapoya site and our research shows evidence for minimal non‐local presence in this commingled burial assemblage. The regional diet reconstructed at Los Pinchudos (2850 masl) focused on resources of higher altitude tuber crops, beans, and grains (C3) and terrestrial protein rather than on lower elevation grasses such as maize (C4) as in other highland Andean regions under Inca control. During imperial domination, inhabitants of this region appropriated Inca materials goods but continued to construct tombs in the local manner even though a potentially diverse population was occupying them.
Survival and dementia in GBA‐associated Parkinson's disease: The mutation matters
Authors: Cilia Roberto , Tunesi Sara , Marotta Giorgio , Cereda Emanuele , Siri Chiara , Tesei Silvana , Zecchinelli Anna L. , Canesi Margherita , Mariani Claudio B. , Meucci Nicoletta , Sacilotto Giorgio , Zini Michela , Barichella Michela , Magnani Corrado , Duga Stefano , Asselta Rosanna , Soldà Giulia , Seresini Agostino , Seia Manuela , Pezzoli Gianni , Goldwurm Stefano
Published: September 2016

Objective

The objective of this work was to investigate survival, dementia, and genotype‐phenotype correlations in patients with Parkinson's disease (PD) with and without mutations on the glucocerebrosidase gene (GBA).

Methods

We included 2,764 unrelated consecutive PD patients: 123 GBA carriers (67 mild‐p.N370S and 56 severe mainly p.L444P) and 2,641 noncarriers. Brain perfusion and dopamine transporter imaging was analyzed, including dementia with Lewy Bodies (DLB) as an additional control group.

Results

Multivariable analysis adjusted by sex, age at onset, and disease duration attributed to GBA carriers a greater risk for dementia (hazard ratio [HR] = 3.16; p < 0.001) and death (HR = 1.85; p = 0.002) than noncarriers. When dementia was introduced in the model as a time‐dependent covariate, the mortality risk remained greater in carriers (HR = 1.65; p = 0.016), suggesting that other clinical features are likely to contribute to reduced survival. At last examination, GBA carriers had worse motor symptoms, particularly nondopaminergic features. Carriers of severe mutations had greater risk for dementia compared to mild mutations (p < 0.001), but similar mortality risk. Consistent with clinical data, GBA carriers showed reduced posterior parietal and occipital cortical synaptic activity and nigrostriatal function than PD noncarriers. Neuroimaging features of carriers of mild mutations overlapped with PD noncarriers, whereas carriers of severe mutations were closer to DLB.

Interpretation

Survival is reduced in GBA carriers compared to noncarriers; this seems to be partially independent from the increased risk for early dementia. The risk for dementia is strongly modulated by type of mutation. In the clinical continuum between PD and DLB, patients with GBA mutations seem to localize midway, with carriers of severe mutations closer to DLB than to idiopathic PD. Ann Neurol 2016;80:662–673
N−H Imine as a Powerful Directing Group for Cobalt‐Catalyzed Olefin Hydroarylation
Authors: Xu Wengang , Yoshikai Naohiko
Published: September 2016

N‐alkyl and N‐aryl imines have been frequently used as directing groups in rhodium‐ and cobalt‐catalyzed hydroarylation reactions of olefins and alkynes. However, the scope of such hydroarylation reactions has been limited by the difficulty of preparation of sterically hindered imines by condensation, and also by the steric bulkiness of the imine group itself. Reported herein is that an N−H imine serves as an alternative and highly effective directing group for cobalt‐catalyzed hydroarylation of olefins, and unlocks many of the limitations associated with the previously employed N‐aryl imine directing group. The power of this minimal nitrogen directing group is manifested in a fourfold ortho alkylation of benzophenone imine, and it occurs rapidly at ambient temperature.
Phase and Interface Engineering of Platinum–Nickel Nanowires for Efficient Electrochemical Hydrogen Evolution
Authors: Wang Pengtang , Jiang Kezhu , Wang Gongming , Yao Jianlin , Huang Xiaoqing
Published: September 2016

The design of high‐performance electrocatalysts for the alkaline hydrogen evolution reaction (HER) is highly desirable for the development of alkaline water electrolysis. Phase‐ and interface‐engineered platinum–nickel nanowires (Pt‐Ni NWs) are highly efficient electrocatalysts for alkaline HER. The phase and interface engineering is achieved by simply annealing the pristine Pt‐Ni NWs under a controlled atmosphere. Impressively, the newly generated nanomaterials exhibit superior activity for the alkaline HER, outperforming the pristine Pt‐Ni NWs and commercial Pt/C, and also represent the best alkaline HER catalysts to date. The enhanced HER activities are attributed to the superior phase and interface structures in the engineered Pt‐Ni NWs.
NHC‐CAAC Heterodimers with Three Stable Oxidation States
Authors: Munz Dominik , Chu Jiaxiang , Melaimi Mohand , Bertrand Guy
Published: September 2016

The synthesis of N‐heterocyclic carbene (NHC)–cyclic (alkyl)(amino) carbene (CAAC) heterodimers is presented. As the free carbenes do not react together in solution, the synthetic approach involves the addition of a free NHC to a cyclic iminium salt, which results in the formation of the protonated heterodimer. Subsequent deprotonation leads to the isolation of the corresponding mixed Wanzlick dimers. One‐ and two‐electron oxidations of these triazaolefins result in the formation of stable cationic radicals and bis(cations), respectively, which have been isolated and fully characterized. Cyclic voltammetry, UV/Vis spectroscopy, spin density, and DFT calculations suggest that these heterodimers feature complementary electronic properties to tetrathiafulvalenes (TTFs).
Catalytic Enantioselective Synthesis of C1‐ and C2‐Symmetric Spirobiindanones through Counterion‐Directed Enolate C‐Acylation
Authors: Rahemtulla Benjamin F. , Clark Hugh F. , Smith Martin D.
Published: September 2016

A catalytic enantioselective route to C1‐ and C2‐symmetric 2,2′‐spirobiindanones has been realized through an intramolecular enolate C‐acylation. This reaction employs a chiral ammonium counterion to direct the acylation of an in situ generated ketone enolate with a pentafluorophenyl ester. This reaction constitutes the first example of a direct catalytic enantioselective C‐acylation of a ketone and provides an efficient and highly enantioselective route to axially chiral spirobiindanediones. These products can be diastereoselectively derivatized, offering access to a range of functionalized spirocyclic architectures.
Subtle Interactions and Electron Transfer between UIII, NpIII, or PuIII and Uranyl Mediated by the Oxo Group
Authors: Arnold Polly L. , Dutkiewicz Michał S. , Zegke Markus , Walter Olaf , Apostolidis Christos , Hollis Emmalina , Pécharman Anne‐Fréderique , Magnani Nicola , Griveau Jean‐Christophe , Colineau Eric , Caciuffo Roberto , Zhang Xiaobin , Schreckenbach Georg , Love Jason B.
Published: September 2016

A dramatic difference in the ability of the reducing AnIII center in AnCp3 (An=U, Np, Pu; Cp=C5H5) to oxo‐bind and reduce the uranyl(VI) dication in the complex [(UO2)(THF)(H2L)] (L=“Pacman” Schiff‐base polypyrrolic macrocycle), is found and explained. These are the first selective functionalizations of the uranyl oxo by another actinide cation. At‐first contradictory electronic structural data are explained by combining theory and experiment. Complete one‐electron transfer from Cp3U forms the UIV‐uranyl(V) compound that behaves as a UV‐localized single molecule magnet below 4 K. The extent of reduction by the Cp3Np group upon oxo‐coordination is much less, with a NpIII‐uranyl(VI) dative bond assigned. Solution NMR and NIR spectroscopy suggest NpIVUV but single‐crystal X‐ray diffraction and SQUID magnetometry suggest a NpIII‐UVI assignment. DFT‐calculated Hirshfeld charge and spin density analyses suggest half an electron has transferred, and these explain the strongly shifted NMR spectra by spin density contributions at the hydrogen nuclei. The PuIII–UVI interaction is too weak to be observed in THF solvent, in agreement with calculated predictions.
3D Framework DNA Origami with Layered Crossovers
Authors: Hong Fan , Jiang Shuoxing , Wang Tong , Liu Yan , Yan Hao
Published: September 2016

Designer DNA architectures with nanoscale geometric controls provide a programmable molecular toolbox for engineering complex nanodevices. Scaffolded DNA origami has dramatically improved our ability to design and construct DNA nanostructures with finite size and spatial addressability. Here we report a novel design strategy to engineer multilayered wireframe DNA structures by introducing crossover pairs that connect neighboring layers of DNA double helices. These layered crossovers (LX) allow the scaffold or helper strands to travel through different layers and can control the relative orientation of DNA helices in neighboring layers. Using this design strategy, we successfully constructed four versions of two‐layer parallelogram structures with well‐defined interlayer angles, a three‐layer structure with triangular cavities, and a 9‐ and 15‐layer square lattices. This strategy provides a general route to engineer 3D framework DNA nanostructures with controlled cavities and opportunities to design host–guest networks analogs to those produced with metal organic frameworks.
A Boryl‐Substituted Diphosphene: Synthesis, Structure, and Reaction with n‐Butyllithium To Form a Stabilized Adduct by pπ‐pπ Interaction
Authors: Asami Shun‐suke , Okamoto Masafumi , Suzuki Katsunori , Yamashita Makoto
Published: September 2016

A boryl‐substituted diphosphene was synthesized through the nucleophilic borylation of PCl3 with a borylzinc reagent, followed by a reduction with Mg. A combined analysis of the resulting diboryldiphosphene by single‐crystal X‐ray diffraction, DFT calculations, and UV/Vis spectroscopy revealed a σ‐electron‐donating effect for the boryl substituent that was slightly weaker than that of the 2,4,6‐tri‐tert‐butylphenyl (Mes*) ligand. The reaction of this diboryldiphosphene with nBuLi afforded a boryl‐substituted phosphinophosphide that was, in comparison with the thermally unstable Mes*‐substituted diaryldiphosphene, stabilized by a π‐electron‐accepting effect of the boryl substituent.
Novel tools for early detection of a global aquatic invasive, the zebra mussel Dreissena polymorpha
Authors: Ardura Alba , Zaiko Anastasija , Borrell Yaisel J. , Samuiloviene Aurelija , Garcia‐Vazquez Eva
Published: September 2016

This study presents a species‐specific DNA‐based marker for detection of the zebra mussel Dreissena polymorpha, recognized as one of the worst invasive species worldwide.

The marker was developed in silico and experimentally tested on environmental samples. Gel and capillary electrophoreses for visualization of the PCR products were compared.

Marker specificity and sensitivity were assessed in vitro by cross‐amplifications and serial dilutions, respectively. The method allows detecting at least 0.7 ng of Dreissena DNA per μL and cross‐species amplification was not found in any case.

Next‐generation sequencing (NGS) metabarcoding (PCR amplification and massive sequencing of a DNA barcode) was used as an independent method for verifying presence of Dreissena DNA molecules in environmental plankton samples collected from the south‐eastern Baltic Sea.

The consistency between NGS results reporting presence of Dreissena and positive PCR amplification of the marker from the plankton samples confirmed the efficacy of this highly reproducible, fast, cheap and technically easy method.

Copyright © 2016 John Wiley & Sons, Ltd.
A Divergent Approach to the Diastereoselective Synthesis of 3,3‐Disubstituted Oxindoles from Atropisomeric N‐Aryl Oxindole Derivatives
Authors: Nakazaki Atsuo , Mori Ayako , Kobayashi Susumu , Nishikawa Toshio
Published: September 2016

3,3‐Disubstituted oxindoles were divergently synthesized by diastereoselective transformations including nucleophilic addition, alkylation, and cycloaddition using common, axially chiral N‐aryl oxindoles. Notably, high diastereoselectivities (up to >95:5) were observed with ortho‐monosubstituted N‐aryl oxindoles to give various oxindole scaffolds, and facile removal of the p‐(benzyloxy)aryl moiety in axially twisted amides was achieved by a mild, two‐step sequence.
Robust Finite‐Time H∞ Control of a Class of Disturbed Systems using Lmi‐Based Approach
Authors: Zhang Xiaoyu , Zhong Jihong , Zhang Quan , Ma Kemao
Published: September 2016

In this paper, the definition of robust finite‐time H∞ control is presented for a class of disturbed systems. Time‐varying norm‐bounded exogenous disturbance is considered in the system. A state feedback controller is designed, via a Linear Matrix Inequalities (LMIs) approach, which ensures that the closed‐loop system is finite‐time bounded (FTB) and reduces the effect of the disturbance input on the controlled output to a prescribed level. The main result, derived by Lyapunov functions, is a sufficient condition for FTB of disturbed systems and the sufficient condition can be reduced to a feasibility problem involving LMIs. Then a DC motor position control problem is simulated as a demonstration for this study. Simulation results are presented to show the effectiveness of the proposed method as a promising approach for controlling similar disturbed systems.
Multicentre study of the impact of morbidity on long-term survival following hepatectomy for intrahepatic cholangiocarcinoma
Authors: Doussot A , Lim C , Gómez-Gavara C , Fuks D , Farges O , Regimbeau J M , Azoulay D , Adam R , Pascal G , Castaing D , Cherqui D , Baulieux J , Mabrut J Y , Ducerf C , Belghiti J , Nuzzo G , Giuliante F , Le Treut Y-P , Hardwigsen J , Pessaux P , Bachellier P , Pruvot F R , Boleslawski E , Rivoire M , Chiche L
Published: September 2016

Background

The impact of morbidity on long-term outcomes following liver resection for intrahepatic cholangiocarcinoma is currently unclear.

Methods

This was a retrospective analysis of all consecutive patients who underwent liver resection for intrahepatic cholangiocarcinoma with curative intent in 24 university hospitals between 1989 and 2009. Severe morbidity was defined as any complication of Dindo–Clavien grade III or IV. Patients with severe morbidity were compared with those without in terms of demographics, pathology, management, morbidity, overall survival, disease-free survival and time to recurrence. Independent predictors of severe morbidity were identified by multivariable analysis.

Results

A total of 522 patients were enrolled. Severe morbidity occurred in 113 patients (21·6 per cent) and was an independent predictor of overall survival (hazard ratio 1·64, 95 per cent c.i. 1·21 to 2·23), as were age at resection, multifocal disease, positive lymph node status and R0 resection margin. Severe morbidity did not emerge as an independent predictor of disease-free survival. Independent predictors of time to recurrence included severe morbidity, tumour size, multifocal disease, vascular invasion and R0 resection margin. Major hepatectomy and intraoperative transfusion were independent predictors of severe morbidity.

Conclusion

Severe morbidity adversely affects overall survival following liver resection for intrahepatic cholangiocarcinoma.
Filtering and storage working memory networks in younger and older age
Authors: Vellage Anne‐Katrin , Becke Andreas , Strumpf Hendrik , Baier Bernhard , Schönfeld Mircea Ariel , Hopf Jens‐Max , Müller Notger G.
Published: September 2016

Introduction

Working memory (WM) is a multi‐component model that among others involves the two processes of filtering and storage. The first reflects the necessity to inhibit irrelevant information from entering memory, whereas the latter refers to the active maintenance of object representations in memory. In this study, we aimed at a) redefining the neuronal networks sustaining filtering and storage within visual working memory by avoiding shortcomings of prior studies, and b) assessing age‐related changes in these networks.

Methods

We designed a new paradigm that strictly controlled for perceptual load by presenting the same number of stimuli in each of three conditions. We calculated fMRI contrasts between a baseline condition (low filter and low storage load) and conditions that posed high demands on filtering and storage, respectively, in large samples of younger (n = 40) and elder (n = 38) participants.

Results

Our approach of comparing contrasts between groups revealed more extensive filter and storage WM networks than previous studies. In the younger group, filtering involved the bilateral insulae, the right occipital cortex, the right brainstem, and the right cerebellum. In the elder group, filtering was associated with the bilateral insulae, right precuneus, and bilateral ventromedial prefrontal cortex. An extensive neuronal network was also found during storage of information in the bilateral posterior parietal cortex, the left ventromedial prefrontal cortex, and the right precuneus in the younger participants. In addition to these brain regions, elder participants recruited the bilateral ventral prefrontal cortex, the superior, middle and inferior and temporal cortex, the left cingulum and the bilateral parahippocampal cortex.

Conclusions

In general, elder participants recruited more brain regions in comparison to younger participants to reach similar accuracy levels. Furthermore, in elder participants one brain region emerged in both contrasts, namely the left ventromedial prefrontal cortex. Hence, elder participants seem to routinely recruit this brain region in demanding tasks, irrespective of whether filtering or storing is challenged.
Associations between cancer and Alzheimer's disease in a U.S. Medicare population
Authors: Freedman Daryl Michal , Wu Jincao , Chen Honglei , Kuncl Ralph W. , Enewold Lindsey R. , Engels Eric A. , Freedman Neal D. , Pfeiffer Ruth M.
Published: September 2016

Several studies have reported bidirectional inverse associations between cancer and Alzheimer's disease (AD). This study evaluates these relationships in a Medicare population. Using Surveillance, Epidemiology, and End Results (SEER) linked to Medicare data, 1992–2005, we evaluated cancer risks following AD in a case–control study of 836,947 cancer cases and 142,869 controls as well as AD risk after cancer in 742,809 cancer patients and a non‐cancer group of 420,518. We applied unconditional logistic regression to estimate odds ratios (ORs) and Cox proportional hazards models to estimate hazards ratios (HRs). We also evaluated cancer in relation to automobile injuries as a negative control to explore potential study biases. In the case–control analysis, cancer cases were less likely to have a prior diagnosis of AD than controls (OR = 0.86; 95% CI = 0.81–0.92). Cancer cases were also less likely than controls to have prior injuries from automobile accidents to the same degree (OR = 0.83; 95% CI = 0.78–0.88). In the prospective cohort, there was a lower risk observed in cancer survivors, HR = 0.87 (95% CI = 0.84–0.90). In contrast, there was no association between cancer diagnosis and subsequent automobile accident injuries (HR = 1.03; 95% CI = 0.98–1.07). That cancer risks were similarly reduced after both AD and automobile injuries suggest biases against detecting cancer in persons with unrelated medical conditions. The modestly lower AD risk in cancer survivors may reflect underdiagnosis of AD in those with a serious illness. This study does not support a relationship between cancer and AD.
Effect of Particle Size upon Pt/SiO2 Catalytic Cracking of n‐Dodecane under Supercritical Conditions: In situ SAXS and XANES Studies
Authors: Lee Sungwon , Lee Sungsik , Kumbhalkar Mrunmayi D. , Wiaderek Kamila M. , Dumesic James , Winans Randall E.
Published: September 2016

The endothermic cracking and dehydrogenation of n‐dodecane is investigated over well‐defined nanometer size platinum catalysts supported on SiO2 to study the particle size effects in the catalytic cracking reaction, with simultaneous in situ monitoring of the particle size and oxidation state of the working catalysts by in situ SAXS (small angle X‐ray scattering) and XAS (X‐ray absorption spectroscopy). The selectivity toward olefins products was found dominant in the 1 nm size platinum catalysts, whereas paraffins are dominant in the 2 nm catalysts. This reveals a strong correlation between catalytic performance and catalyst size as well as the stability of the nanoparticles in supercritical condition of n‐dodecane. The presented results suggest that controlling the size and geometric structure of platinum nanocatalysts could lead to a fundamentally new level of understanding of nanoscale materials by monitoring the catalysts in realistic reaction conditions.