bluuebunny/crossref_metadata_2025 huggingface dataset:
Tunable Fano Resonance and Plasmon–Exciton Coupling in Single Au Nanotriangles on Monolayer WS2 at Room Temperature
Authors: Wang Mingsong , Krasnok Alex , Zhang Tianyi , Scarabelli Leonardo , Liu He , Wu Zilong , Liz‐Marzán Luis M. , Terrones Mauricio , Alù Andrea , Zheng Yuebing
Published: April 2018

Tunable Fano resonances and plasmon–exciton coupling are demonstrated at room temperature in hybrid systems consisting of single plasmonic nanoparticles deposited on top of the transition metal dichalcogenide monolayers. By using single Au nanotriangles (AuNTs) on monolayer WS2 as model systems, Fano resonances are observed from the interference between a discrete exciton band of monolayer WS2 and a broadband plasmonic mode of single AuNTs. The Fano lineshape depends on the exciton binding energy and the localized surface plasmon resonance strength, which can be tuned by the dielectric constant of surrounding solvents and AuNT size, respectively. Moreover, a transition from weak to strong plasmon–exciton coupling with Rabi splitting energies of 100–340 meV is observed by rationally changing the surrounding solvents. With their tunable plasmon–exciton interactions, the proposed WS2–AuNT hybrids can open new pathways to develop active nanophotonic devices.
Porphyrin Organic Framework Hollow Spheres and Their Applications in Lithium–Sulfur Batteries
Authors: Li Bo‐Quan , Zhang Shu‐Yuan , Kong Long , Peng Hong‐Jie , Zhang Qiang
Published: April 2018

Organic frameworks represent an emerging family of advanced materials that can be precisely controlled at the atomic level. However, morphology control of organic frameworks remains perplexing and difficult, strongly limiting the advantages of organic frameworks in multiple practical applications. Herein, porphyrin organic framework hollow spheres (POF‐HSs) are fabricated by a template method as a proof of concept of organic frameworks with precisely controlled morphology. POF‐HS exhibits explicit chemical structures of 2D POF and an expected hollow structure. The morphology of POF‐HS is further regulated in terms of void size and shell thickness. Benefited from the polar chemical structures and the hollow spherical morphology, POF‐HS sufficiently mitigates the shuttle of polysulfides by taking the dual effects of chemical adsorption and physical confinement and functions as a desirable host material for sulfur cathode to endow lithium–sulfur batteries with high capacity, long cycling life, and excellent rate performance. The accurate synthesis of POF‐HSs demonstrates the highly controllable and versatile morphology of organic framework materials beyond precise integration of organic building blocks and represents infinite possibility of offering exotic organic frameworks for chemistry, sustainable energy, and material science.
Phosphine‐Catalyzed Domino Reaction of α,β‐Unsaturated Ketone and Allenoate: Stereoselective Synthesis of Polysubstituted Dihydro‐2H‐Pyran
Authors: Li Jianxiong , Chen Yaoyao , Yuan Hongdong , Hu Jie , Cui Yongmei , Yang Meng , Li Min , Li Jian
Published: April 2018

A phosphine‐catalyzed domino reaction of allenoate and two molecular α,β‐unsaturated ketone is reported. In particular, this unexpected strategy incorporates [2+4] annulation and subsequent Michael addition into one reaction, thus providing a new access to polysubstituted dihydropyran derivatives in an efficient manner. The reaction optimization outcome reveals that not only the catalyst, but also the experiment parameters including the solvent and temperature play significant roles for the synthesis of the products. This protocol represents a new reaction mode of two basic chemicals involving C−C and C−O bond‐forming process. The present strategy also features the excellent stereoselectivity, broad substrate scope and atom economy.

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Cross‐linked ultra‐high‐molecular‐weight polyethylene prepared by silane‐induced cross‐linking under in situ development of water
Authors: Li Qiuying , Chen Tenghui , Sun Lewen , Guo Weihong , Wu Chifei
Published: April 2018

This work aimed at providing a suitable method for preparing the cross‐linked ultra‐high‐molecular‐weight polyethylene (UHMWPE). First, UHMWPE was grafted with a silane compound using organic peroxide as an initiator in the molten state. Then, cross‐linking was performed by compression molding of the mixture of the silane‐grafted UHMWPE and CaC2O4·H2O. Water released from CaC2O4·H2O made the silane‐grafted UHMWPE cross‐link. In particular, no catalyst was added in the cross‐linking step. Fourier Transform Infrared results confirmed that the silane has been grafted onto the UHMWPE chain successfully and the grafting index varied with the dosage of the initiator. With the increasing of CaC2O4·H2O content, the gel ratio increased and average molecular weight of the cross‐linked UHMWPE decreased, which proved that the cross‐linked UHMWPE can be prepared by this method. Moreover, there existed different cross‐linked network structures (loose and tight networks) in the samples with the same gel ratio.
Predictors of Farmers’ Market Shopping among People Receiving Supplemental Nutrition Assistance Program Benefits
Authors: Freedman Darcy A. , Lee Eunlye , Ohri‐Vachaspati Punam , Trapl Erika , Borawski Elaine , Bess Kimberly , Flocke Susan
Published: April 2018

Promoting use of farmers’ markets (FMs) is a promising community‐level strategy to increase access to nutritious foods such as fruits and vegetables. Yet, FM shopping among people with Supplemental Nutrition Assistance Program (SNAP) benefits remains low. This research examined predictors of FM shopping among SNAP recipients living within 1 mile of a FM. A cross‐sectional survey of SNAP participants (N = 270) was conducted in 2015 in Cleveland and East Cleveland, OH, USA. Multinomial regression and zero‐truncated Poisson regression analyses were conducted to examine factors associated with FM shopping. Results indicate 48% reported shopping at a FM at least once in the past year, 26% had shopped at a FM before, but not in the last year, and 26% had never shopped at a FM. The multivariable analyses found awareness of FMs and a healthy food incentive program, and four dimensions of healthy food access are significantly associated with FM shopping among SNAP recipients. The food access dimensions included service delivery, spatial‐temporal, personal, and social access. Findings highlight modifiable leverage points for improving the reach of FMs among low‐income populations.
RASopathies are associated with a distinct personality profile
Authors: Bizaoui Varoona , Gage Jessica , Brar Rita , Rauen Katherine A. , Weiss Lauren A.
Published: April 2018

Personality is a complex, yet partially heritable, trait. Although some Mendelian diseases like Williams‐Beuren syndrome are associated with a particular personality profile, studies have failed to assign the personality features to a single gene or pathway. As a family of monogenic disorders caused by mutations in the Ras/MAPK pathway known to influence social behavior, RASopathies are likely to provide insight into the genetic basis of personality. Eighty subjects diagnosed with cardiofaciocutaneous syndrome, Costello syndrome, neurofibromatosis type 1, and Noonan syndrome were assessed using a parent‐report BFQ‐C (Big Five Questionnaire for Children) evaluating agreeableness, extraversion, conscientiousness, intellect/openness, and neuroticism, along with 55 unaffected sibling controls. A short questionnaire was added to assess sense of humor. RASopathy subjects and sibling controls were compared for individual components of personality, multidimensional personality profiles, and individual questions using Student tests, analysis of variance, and principal component analysis. RASopathy subjects were given lower scores on average compared to sibling controls in agreeableness, extraversion, conscientiousness, openness, and sense of humor, and similar scores in neuroticism. When comparing the multidimensional personality profile between groups, RASopathies showed a distinct profile from unaffected siblings, but no difference in this global profile was found within RASopathies, revealing a common profile for the Ras/MAPK‐related disorders. In addition, several syndrome‐specific strengths or weaknesses were observed in individual domains. We describe for the first time an association between a single pathway and a specific personality profile, providing a better understanding of the genetics underlying personality, and new tools for tailoring educational and behavioral approaches for individuals with RASopathies.
Efficient CO2 Insertion and Reduction Catalyzed by a Terminal Zinc Hydride Complex
Authors: Tüchler Michael , Gärtner Lisa , Fischer Susanne , Boese A. Daniel , Belaj Ferdinand , Mösch‐Zanetti Nadia C.
Published: April 2018

The terminal zinc hydride complex [Tntm]ZnH (2; Tntm=tris(6‐tert‐butyl‐3‐thiopyridazinyl)methanide) is an efficient hydrosilylation catalyst of CO2 at room temperature without the need of Lewis acidic additives. The inherent electrophilicity of the system leads to selective formation of the monosilylated product (MeO)3SiO2CH (at room temperature with a TOF of 22.2 h−1 and at 45 °C with a TOF of 66.7 h−1). In absence of silanes, the intermediate formate complex [Tntm]Zn(O2CH) (3) is quantitatively formed within 5 min. All complexes were fully characterized by 1H and 13C NMR spectroscopy and single‐crystal X‐ray diffraction analyses. Density functional theory (DFT) calculations reveal a high positive charge on zinc and the increased preference of the ligand to adopt a κ3‐coordination mode.
Regioselective Formation of (E)‐β‐Vinylstannanes with a Topologically Controlled Molybdenum‐Based Alkyne Hydrostannation Catalyst
Authors: Mandla Kyle A. , Moore Curtis E. , Rheingold Arnold L. , Figueroa Joshua S.
Published: April 2018

The regioselective formation of (E)‐β‐vinylstannanes has been a long‐standing challenge in transition‐metal‐catalyzed alkyne hydrostannation. Herein, we report a well‐defined molybdenum‐based system featuring two encumbering m‐terphenyl isocyanides that reliably and efficiently delivers (E)‐β‐vinylstannanes from a range of terminal and internal alkynes with high regioselectivity. The system is particularly effective for aryl alkynes and can discriminate between alkyl chains of low steric hindrance in unsymmetrically substituted dialkyl alkynes. Catalytic hydrostannation with this system is also characterized by an electronic effect that leads to a decrease in regioselectivity when electron‐withdrawing groups are present on the alkyne substrate.
Rapid Aqueous Late‐Stage Radiolabelling of [GaF3(BnMe2‐tacn)] by 18F/19F Isotopic Exchange: Towards New PET Imaging Probes
Authors: Monzittu Francesco M. , Khan Imtiaz , Levason William , Luthra Sajinder K. , McRobbie Graeme , Reid Gillian
Published: April 2018

A simple and rapid method for 18F radiolabelling of [GaF3(BnMe2‐tacn)] by 18F/19F isotopic exchange is described. The use of MeCN/H2O or EtOH/H2O (75:25) and aqueous [18F]F− (up to 200 MBq) with heating (80 °C, 10 min) gave 66±4 % 18F incorporation at a concentration of 268 nm, and 37±5 % 18F incorporation at even lower concentration (27 nm), without the need for a Lewis acid promoter. A solid‐phase extraction method was established to give [Ga18F19F2(BnMe2‐tacn)] in 99 % radiochemical purity in an EtOH/H2O mixture.
Regioselective C−H Xanthylation as a Platform for Polyolefin Functionalization
Authors: Williamson Jill B. , Czaplyski William L. , Alexanian Erik J. , Leibfarth Frank A.
Published: April 2018

Polyolefins that contain polar functional groups are important materials for next‐generation lightweight engineering thermoplastics. Post‐polymerization modification is an ideal method for the incorporation of polar groups into branched polyolefins; however, it typically results in chain scission events, which have deleterious effects on polymer properties. Herein, we report a metal‐free method for radical‐mediated C−H xanthylation that results in the regioselective functionalization of branched polyolefins without coincident polymer‐chain scission. This method enables a tunable degree of polymer functionalization and capitalizes on the versatility of the xanthate functional group to unlock a wide variety of C−H transformations previously inaccessible on branched polyolefins.
Enantioselective Formation of 2‐Azetidinones by Ring‐Assisted Cyclization of Interlocked N‐(α‐Methyl)benzyl Fumaramides
Authors: Martinez‐Cuezva Alberto , Bautista Delia , Alajarin Mateo , Berna Jose
Published: April 2018

The synthesis of optically active interlocked and non‐interlocked 2‐azetidinones by intramolecular cyclization of N‐(α‐methyl)benzyl fumaramide [2]rotaxanes is described. Two different strategies of asymmetric induction were tested in which the chiral group was located either proximal or distal to the reacting center of the thread. During these experiments, an interesting equilibration process inside the macrocyclic void occurred, thus leading to the cyclization through the (α‐methyl)benzyl carbon atom and giving rise to β‐lactams, with a quaternary carbon atom, in an enantio‐ and diastereocontrolled manner. This cyclization also proceeds in kinetically stable chiral pseudo[2]rotaxanes, thus allowing further dethreading to provide enantioenriched 3,4‐disubstituted trans‐2‐azetidinones. The stereochemical outcomes of the cyclizations inside and outside the macrocycle demonstrated noticeable differences.
Catholyte‐Free Electrocatalytic CO2 Reduction to Formate
Authors: Lee Wonhee , Kim Young Eun , Youn Min Hye , Jeong Soon Kwan , Park Ki Tae
Published: April 2018

Electrochemical reduction of carbon dioxide (CO2) into value‐added chemicals is a promising strategy to reduce CO2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO2 reduction (CO2R) is the low solubility of CO2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte‐free electrocatalytic CO2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm−2, despite the decrease in CO2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L−1 is obtained as a one‐path product at 343 K with high PCD (51.7 mA cm−2) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V.
Reversible Response of Luminescent Terbium(III)–Nanocellulose Hydrogels to Anions for Latent Fingerprint Detection and Encryption
Authors: Hai Jun , Li Tianrong , Su Junxia , Liu Weisheng , Ju Yanmin , Wang Baodui , Hou Yanglong
Published: April 2018

Fingerprint fluorescence imaging has become one of the most prominent technologies in the field of forensic medicine, but it seldom considers the security protection of detection information, which is of great importance in modern society. Herein we demonstrate that luminescent TbIII–carboxymethyl cellulose (CMC) complex binding aptamer hydrogels that are reversibly responsive to ClO−/SCN− can be used for the selective detection, protection, and storage of fingerprint information. The imaging information of the fingerprint can be quenched and recovered by ClO−/SCN− regulation, respectively, resulting in reversible on/off conversion of the luminescence signals for the encryption and decryption of multiple levels of information. The present study opens new avenues for multilevel imaging, data recording, and security protection of fingerprint information with tunable fluorescent hydrogels.
Selective Hydrogenation of CO2 to Ethanol over Cobalt Catalysts
Authors: Wang Lingxiang , Wang Liang , Zhang Jian , Liu Xiaolong , Wang Hai , Zhang Wei , Yang Qi , Ma Jingyuan , Dong Xue , Yoo Seung Jo , Kim Jin‐Gyu , Meng Xiangju , Xiao Feng‐Shou
Published: April 2018

Methods for the hydrogenation of CO2 into valuable chemicals are in great demand but their development is still challenging. Herein, we report the selective hydrogenation of CO2 into ethanol over non‐noble cobalt catalysts (CoAlOx), presenting a significant advance for the conversion of CO2 into ethanol as the major product. By adjusting the composition of the catalysts through the use of different prereduction temperatures, the efficiency of CO2 to ethanol hydrogenation was optimized; the catalyst reduced at 600 ° gave an ethanol selectivity of 92.1 % at 140 °C with an ethanol time yield of 0.444 mmol g−1 h−1. Operando FT‐IR spectroscopy revealed that the high ethanol selectivity over the CoAlOx catalyst might be due to the formation of acetate from formate by insertion of *CHx, a key intermediate in the production of ethanol by CO2 hydrogenation.
Organocatalytic Atroposelective Intramolecular [4+2] Cycloaddition: Synthesis of Axially Chiral Heterobiaryls
Authors: Liu Yidong , Wu Xiaoyan , Li Shan , Xue Lu , Shan Chunhui , Zhao Zhengxing , Yan Hailong
Published: April 2018

The enantioselective construction of axially chiral aryl‐naphthopyran skeletons was realized by organocatalytic atroposelective intramolecular [4+2] cycloaddition of in situ generated vinylidene ortho‐quinone methides, from 2‐ethynylphenol derivatives, with alkynes. Through this method, the heteroatropisomers were obtained with excellent yields and enantioselectivities. Moreover, a speculative model of the stereochemical outcome is proposed based on preliminary mechanistic studies. The products having various functional groups can be easily transformed into valuable intermediates as either potential ligands or organocatalysts.
Direct Aryloxylation/Alkyloxylation of Dialkyl Phosphonates for the Synthesis of Mixed Phosphonates
Authors: Huang Hai , Denne Johanna , Yang Chou‐Hsun , Wang Haobin , Kang Jun Yong
Published: April 2018

A strategy for the direct functionalization strategy of inertial dialkyl phosphonates with hydroxy compounds to afford diverse mixed phosphonates with good yields and functional‐group tolerance has been developed. Mechanistic investigations involving both NMR studies and DFT studies suggest that an unprecedented highly reactive PV species (phosphoryl pyridin‐1‐ium salt), a key intermediate for this new synthetic transformation, is generated in situ from dialkyl phosphonate in the presence of Tf2O/pyridine.
Design of Trifluoroalkenyl Iodonium Salts for a Hypervalency‐Aided Alkenylation–Cyclization Strategy: Metal‐Free Construction of Aziridine Rings
Authors: Mészáros Ádám , Székely Anna , Stirling András , Novák Zoltán
Published: April 2018

The synthesis of fluorinated compounds and their use as pharmaceutical ingredients or synthetic building blocks have been in the focus of chemical and medicinal research. However, the efficient synthesis of trifluoromethylated nitrogen heterocycles is sometimes challenging. Herein, we disclose a simple aziridination process that relies on the use of amines and novel alkenyl iodonium reagents for the synthesis of strained, trifluoromethylated heterocycles. With the utilization of a newly designed and bench‐stable but highly reactive hypervalent alkenyl iodonium species, these three‐membered‐ring heterocyclic compounds can be efficiently constructed from simple amines under mild conditions in the absence of transition‐metal catalysts. The special reactivity of the new trifluoropropenyl synthon towards nucleophilic centers could be exploited in more general cyclization and alkenylation reactions in the future.
CuH‐Catalyzed Asymmetric Hydroamidation of Vinylarenes
Authors: Zhou Yujing , Engl Oliver D. , Bandar Jeffrey S. , Chant Emma D. , Buchwald Stephen L.
Published: April 2018

A CuH‐catalyzed enantioselective hydroamidation reaction of vinylarenes has been developed using readily accessible 1,4,2‐dioxazol‐5‐ones as electrophilic amidating reagents. This method provides a straightforward and efficient approach to synthesize chiral amides in good yields with high levels of enantiopurity under mild conditions. Moreover, this transformation tolerates substrates bearing a broad range of functional groups.
Cobalt‐Catalyzed Intramolecular Reactions between a Vinylcyclopropane and an Alkyne: Switchable [5+2] Cycloaddition and Homo‐Ene Pathways
Authors: Wu Chunlin , Yoshikai Naohiko
Published: April 2018

Cobalt–diphosphine catalysts have been found to promote intramolecular reactions between a vinylcyclopropane and an alkyne to selectively afford either the [5+2] cycloaddition product or the homo‐ene reaction product under solvent control. The former product is exclusively formed in noncoordinating 1,2‐dichloroethane, whereas the latter is dominant in coordinating solvents, such as acetonitrile and dimethylacetamide. Furthermore, a highly enantioselective variant of the homo‐ene reaction afforded chiral tetrahydrofuran, pyrrolidine, and cyclopentane derivatives bearing 1,3‐diene and alkylidene substituents.
Electrochemical Functional‐Group‐Tolerant Shono‐type Oxidation of Cyclic Carbamates Enabled by Aminoxyl Mediators
Authors: Wang Fei , Rafiee Mohammad , Stahl Shannon S.
Published: April 2018

An electrochemical method has been developed for α‐oxygenations of cyclic carbamates by using a bicyclic aminoxyl as a mediator and water as the nucleophile. The mediated electrochemical process enables substrate oxygenation to proceed at a potential that is approximately 1 V lower than the redox potential of the carbamate substrate. This feature allows for functional‐group compatibility that is inaccessible with conventional Shono oxidations, which proceed by direct electrochemical substrate oxidation. This reaction also represents the first α‐functionalization of non‐activated cyclic carbamates with oxoammonium oxidants.
Variation among macroinvertebrate communities suggests the importance of conserving desert springs
Authors: Stanislawczyk Keara , Walters Ashley D. , Haan Tara J. , Sei Makiri , Lang Brian K. , Berg David J.
Published: April 2018

Desert springs are highly threatened ecosystems inhabited by a substantial number of endemic species.

Macroinvertebrate communities of five springs in the northern Chihuahuan Desert of west Texas and south‐eastern New Mexico were sampled seasonally. Rather than focusing on individual taxa, this study examined the community structure of springs to identify patterns that are likely to reflect both local conditions and potential dispersal barriers.

In total, 46 774 individuals representing 109 taxa were collected with high relative abundances of gastropods, amphipods, and oligochaetes. Spatial variation in community composition was greater than temporal variation.

Although there were differences in the salinity content and concentrations of several major anions and cations among sites, these were not significant predictors of difference in community structure. Two springs sharing the same groundwater source contained similar macroinvertebrate communities and had similar physicochemical conditions. Results from this study suggest that springs in the northern Chihuahuan Desert contain unique communities and endemic species owing to historical processes such as isolation and dispersal limitation, rather than contemporary processes such as environmental filtering and species sorting.

Springs located in the northern Chihuahuan Desert, like those located in other arid regions of the world, are valuable for their biodiversity because of their distinct invertebrate communities and high rates of endemism. Thus, they should be conserved individually to ensure the preservation of unique species and communities.
An investigation of salmonid host utilization by the endangered freshwater pearl mussel (Margaritifera margaritifera) in north‐west Scotland
Authors: Clements Elizabeth A. , Thomas Rhian , Adams Colin E.
Published: April 2018

The complex life cycle of the globally threatened Margaritifera margaritifera includes a parasitic stage, where glochidia attach to the gills of fishes of the genus Salmo; however, the species of Salmo used appears to vary across its range. In previous literature the reported primary host in Scotland, home to a high proportion of the world's remaining M. margaritifera populations, is the Atlantic salmon Salmo salar, and in its absence the brown trout Salmo trutta.

In this study, the prevalence of infection in putative Salmo hosts in eight rivers in north‐west Scotland was determined. At a selected site on each river, where both S. trutta and S. salar were collected in abundance, S. trutta was the preferred host.

At sites where S. salar were abundant but S. trutta were at low density, however, S. salar showed a high prevalence of infection (with the exception of one river where neither S. salar nor S. trutta were infected). Thus, the primary host appears to be very site‐specific in the rivers sampled.

We speculate that this may be because M. margaritifera have population‐specific responses to cues for attachment to a host. Alternatively, it may be that host population‐specific immune responses mediate infections by glochidia. In addition, larger fish were less likely to be infected than smaller fish, and gills 1 and 5 were less heavily infected than gills 2–4.

One consequence of this finding, for both national and international conservation management of this globally endangered species, is that any current or future management activity must take into account local population host preferences, otherwise conservation efforts may be in vain.
Development and Functional Organization of the Cranial Nerves in Lampreys
Authors: Pombal Manuel A. , Megías Manuel
Published: April 2018

Lampreys, together with hagfishes, are the only extant representatives of the oldest branch of vertebrates, the agnathans, which are the sister group of gnathostomes; therefore, studies on these animals are of great evolutionary significance. Lampreys exhibit a particular life cycle with remarkable changes in their behavior, concomitant, in part, with important modifications in the head and its musculature, which might influence the development of the cranial nerves. In this context, some cranial nerves such as the optic nerve and the ocular motor nerves, which develop slowly during an extremely long larval period lasting more than five years, have been more thoroughly investigated; however, much less experimental information is available about others, such as the facial or the hypoglossal nerves. In addition, the possible existence of a “true” accessory nerve in these animals is still a matter of conjecture. Although growing in last decades, investigations on the physiology of the lamprey cranial nerves is scanty. This review focuses on past and recent findings that have contributed to characterize the anatomical organization of the cranial nerves in lampreys, including their components and nuclei, and their relations in the brain; in addition, comments on their development and functional role are also included. Anat Rec, 302:512–539, 2019. © 2018 Wiley Periodicals, Inc.
Hypochlorite‐Mediated Modulation of Photoinduced Electron Transfer in a Phenothiazine–Boron dipyrromethene Electron Donor–Acceptor Dyad: A Highly Water Soluble “Turn‐On” Fluorescent Probe for Hypochlorite
Authors: Soni Disha , Duvva Naresh , Badgurjar Deepak , Roy Tapta Kanchan , Nimesh Surendra , Arya Geeta , Giribabu Lingamallu , Chitta Raghu
Published: April 2018

A highly water‐soluble phenothiazine (PTZ)–boron dipyrromethene (BODIPY)‐based electron donor–acceptor dyad (WS‐Probe), which contains BODIPY as the signaling antennae and PTZ as the OCl− reactive group, was designed and used as a fluorescent chemosensor for the detection of OCl−. Upon addition of incremental amounts of NaOCl, the quenched fluorescence of WS‐Probe was enhanced drastically, which indicated the inhibition of reductive photoinduced electron transfer (PET) from PTZ to 1BODIPY*; the detection limit was calculated to be 26.7 nm. Selectivity studies with various reactive oxygen species, cations, and anions revealed that WS‐Probe was able to detect OCl− selectively. Steady‐state fluorescence studies performed at varied pH suggested that WS‐Probe can detect NaOCl and exhibits maximum fluorescence in the pH range of 7 to 8, similar to physiological conditions. ESI‐MS analysis and 1H NMR spectroscopy titrations showed the formation of sulfoxide as the major oxidized product upon addition of hypochlorite. More interestingly, when WS‐Probe was treated with real water samples, the fluorescence response was clearly visible with tap water and disinfectant, which indicated the presence of OCl− in these samples. The in vitro cell viability assay performed with human embryonic kidney 293 (HEK 293) cells suggested that WS‐probe is non‐toxic up to 10 μm and implicates the use of the probe for biological applications.
Ruthenium(II)−Bipyridine/NanoC3N4 Hybrids: Tunable Photochemical Properties by Using Exchangeable Alkali Metal Cations
Authors: Mori Kohsuke , Tatsumi Daisuke , Iwamoto Tomoyuki , Masui Yoichi , Onaka Makoto , Yamashita Hiromi
Published: April 2018

A series of nanoporous carbon nitrides that contained a range of alkali metal cations (M@nanoC3N4: M=Li+, Na+, K+, Rb+, and Cs+) have been successfully synthesized from as‐synthesized g‐C3N4 by delamination with concentrated sulfuric acid, followed by neutralization with aqueous solutions of the corresponding alkali metal hydroxides. Tris(2,2′‐bipyridine)ruthenium(II) complexes, [Ru(bpy)3]2+, were grafted onto the carbon nitrides in an effort to explore the physicochemical properties of the deposited [Ru(bpy)3]2+, as well as its photocatalytic activity in the aerobic photooxidation of phenylboronic acid and H2 production from aqueous media in the presence of a Pt co‐catalyst under visible‐light irradiation. Highly porous nanoC3N4 could significantly enhance photocatalytic activity, because of its high surface area, owing to its unique porous structure. More interestingly, the photoluminescence intensities of [Ru(bpy)3]2+ complexes that were associated with M@nanoC3N4 increased in the presence of lighter alkali metal cations, which correlated with increased photocatalytic activities for both reactions. This study demonstrates that M@nanoC3N4 are fascinating supports, in which the local environment of an immobilized metal complex can be precisely controlled by varying the alkali metal cation from Li+ to Cs+.
Vergleichende Betrachtung klimatischer Referenzdatensätze hinsichtlich ihres Einflusses auf die energetische Simulation eines Gebäudes
Authors: Schöner Tobias , Zirkelbach Daniel
Published: April 2018

Die Bedeutung von Simulationen des Bauteil‐ und Gebäudeverhaltens als Teil einer ganzheitlichen Betrachtung im Rahmen des Building Information Modeling (BIM) nimmt stetig zu. Die Qualität der erzeugten Ergebnisse wird dabei maßgeblich von den gewählten klimatischen Randbedingungen bestimmt. Derzeit ist der Anwender dazu gezwungen, abhängig von der Fragestellung unterschiedliche klimatische Referenzdatensätze für seine Simulation zu verwenden. In diesem Beitrag wird die Auswirkung unterschiedlicher deutscher Referenzklimata auf den Gebäudeenergiebedarf eines Beispielgebäudes näher betrachtet. Für den Vergleich werden die stationären Heizgradtage sowie das instationäre Gebäudeverhalten bei Verwendung unterschiedlicher Randbedingungen miteinander verglichen. Abschließend werden die mit den Referenzdatensätzen erzeugten Ergebnisse in Relation zu den natürlich auftretenden klimatischen Schwankungen gesetzt.
The Butanol Producing Microbe Clostridium beijerinckii NCIMB 14988 Manipulated Using Forward and Reverse Genetic Tools
Authors: Little Gareth T. , Willson Benjamin J. , Heap John T. , Winzer Klaus , Minton Nigel P.
Published: April 2018

The solventogenic anaerobe Clostridium beijerinckii has potential for use in the sustainable bioconversion of plant‐derived carbohydrates into solvents, such as butanol or acetone. However, relatively few strains have been extensively characterised either at the genomic level or through exemplification of a complete genetic toolkit. To remedy this situation, a new strain of C. beijerinckii, NCIMB 14988, is selected from among a total of 55 new clostridial isolates capable of growth on hexose and pentose sugars. Chosen on the basis of its favorable properties, the complete genome sequence of NCIMB 14988 is determined and a high‐efficiency plasmid transformation protocol devised. The developed DNA transfer procedure allowed demonstration in NCIMB 14988 of the forward and reverse genetic techniques of transposon mutagenesis and gene knockout, respectively. The latter is accomplished through the successful deployment of both group II intron retargeting (ClosTron) and allelic exchange. In addition to gene inactivation, the developed allelic exchange procedure is used to create point mutations in the chromosome, allowing for the effect of amino acid changes in enzymes involved in primary metabolism to be characterized. ClosTron mediated disruption of the currently unannotated non‐coding region between genes LF65_05915 and LF65_05920 is found to result in a non‐sporulating phenotype.
Systematic review of the influence of socioeconomic deprivation on mortality after colorectal surgery
Authors: Poulton T E , Salih T , Martin P , Rojas-Garcia A , Raine R , Moonesinghe S R
Published: April 2018

Background

Socioeconomic deprivation is a potentially important factor influencing surgical outcomes. This systematic review aimed to summarize the evidence for any association between socioeconomic group and mortality after colorectal surgery, and to report the definitions of deprivation used and the approaches taken to adjust for co-morbidity in this patient population.

Methods

MEDLINE, Embase, the Cochrane Library and Web of Science were searched for studies up to November 2016 on adult patients undergoing major colorectal surgery, which reported on mortality according to socioeconomic group. Risk of bias and study quality were assessed by extracting data relating to study size, and variations in inclusion and exclusion criteria. Quality was assessed using a modification of a previously described assessment tool.

Results

The literature search identified 59 studies published between 1993 and 2016, reporting on 2 698 403 patients from eight countries. Overall findings showed evidence for higher mortality in more deprived socioeconomic groups, both in the perioperative period and in the longer term. Studies differed in how they defined socioeconomic groups, but the most common approach was to use one of a selection of multifactorial indices based on small geographical areas. There was no consistent approach to adjusting for co-morbidity but, where this was considered, the Charlson Co-morbidity Index was most frequently used.

Conclusion

This systematic review suggests that socioeconomic deprivation influences mortality after colorectal surgery.
With a little help from a stranger: The impact of external change agents on corporate sustainability investments
Authors: Hoppmann Joern , Sakhel Alice , Richert Marcel
Published: April 2018

We investigate the role external change agents (e.g., consultants), play in stimulating corporate sustainability investments. Using data on more than 5,300 energy efficiency investment decisions by 462 firms, we find that firms that draw more strongly on external change agents seize significantly more sustainable investment opportunities. We show that external change agents are more effective in stimulating investments if they broadly search for investment opportunities and are more strongly involved in the implementation of change initiatives. Moreover, surprisingly, we do not find that using internal change agents in parallel with external agents enhances the effectiveness of external change agents. Our findings have important implications for the literature on corporate sustainability as they point to external change agents as an important means of steering firms onto more sustainable pathways. Additionally, we shed light on the conditions under which external change agents can be used to most effectively overcome organizational path dependencies.
Traditional and new media's influence on suicidal behavior and contagion
Authors: Ortiz Patricia , Khin Khin Eindra
Published: April 2018

The role of nonfictional and fictional media in suicide contagion has been well established, ostensibly beginning with the publication of Goethe's The Sorrows of Young Werther in 1774. In recent decades, the emergence of several new forms of media (e.g. websites, social media, blogs, smartphone applications) has revolutionized the communication and social interaction paradigms. This article reviews “the Werther effect” (or suicide contagion related to media), special populations who are more influential or susceptible, current media reporting guidelines and their effectiveness, and the latest research on new media and its effect on suicide and suicide contagion. The aim is to update recommendations on how to mitigate the potential negative effects of both traditional and new media on suicidal behavior and suicide contagion.
MiR‐340 suppresses the metastasis by targeting EphA3 in cervical cancer
Authors: Xiao Hemei , Yu Lijie , Li Fengdan , Wang Haili , Li Wenxiu , He Xinxia
Published: April 2018

MicroRNAs (miRNAs) play key roles in cervical cancer metastasis progression. Accumulated evidences have revealed that miRNAs are related to the pathophysiological process. However, the role of miR‐340 in cervical cancer and how it works is still not fully interpreted. Using qRT‐PCR to examine the expression of miR‐340 in cervical cancer tissues. Transwell migration and invasion experiments were used to detect the role of miR‐340 in migration and invasion. Luciferase reporter assay, qRT‐PCR, and Western blot were used to detect the relationship between miR‐340 and EphA3. Using Transwell migration and invasion experiments to investigate the role of EphA3 on migration and invasion. Restoration expriments were also performed. Western blot was used to assay the influence of miR‐340 and EphA3 on EMT. We found that miR‐340 was downregulated in cervical cancer tissues compared with the normal tissues. Transwell migration and invasion experiments indicated that overexpression of miR‐340 frequently inhibited the migration and invasion of cervical cancer cells. EphA3 is a target of miR‐340, and ectopic expression of EphA3 can promote the migration and invasion of cervical cancer cells, whereas restoration of EphA3 in miR‐340‐overexpressing cervical cancer cells reversed the suppressive effects of miR‐340. What's more, the process of migration and invasion which regulated by miR‐340/EphA3 was depended on adjusting the EMT way. These findings indicate that miR‐340 may act as an anti‐tumor factor during the process of tumor metastasis through targeting EphA3, suggesting that miR‐340 might be a potential new diagnostic and therapeutic molecule for the treatment of cervical cancer.
Dynamics and Rigidity of an Intact Filamentous Bacteriophage Virus Probed by Magic Angle Spinning NMR
Authors: Aharoni Tom , Goldbourt Amir
Published: April 2018

The capsid dynamics of filamentous bacteriophages is related to their function, stability, and interactions with the genome, and can be assessed by measuring the chemical shift anisotropy (CSA) of 15N amides, which are sensitive to large amplitude motions. In this study, CSA recoupling experiments under magic‐angle spinning NMR were used to probe the dynamics of the y21m capsid mutant of fd bacteriophage. Based on fitting the generated CSA lineshapes, residues located in the N‐terminus undergo increased motional amplitudes suggesting its global motion, whereas other backbone residues are rigid, and imply a tight hydrophobic packing of the phage.
Majority‐Rules Effect and Allostery in Molecular Recognition of Calix[4]arene‐Based Triple‐Stranded Metallohelicates
Authors: Yamasaki Yutaro , Shio Hidemi , Amimoto Tomoko , Sekiya Ryo , Haino Takeharu
Published: April 2018

The triple‐stranded metallohelicates1 a,/1 b–3 a/3 bpossessing internal guest binding cavities surrounded by calix[4]arene units were synthesized through coordination‐driven self‐assembly. UV/Vis titration experiments verified that the metallohelicates encapsulatedN‐methyl pyridinium cations bearing amino acid groups to form host–guest complexes. The guest chirality was transferred to the helicity of the helicates through the steric contact between the stereogenic center of the amino acid group and the metal cores. The (M) helicity was induced when guests the (R)‐4‐‐(R)‐6were accommodated within the cavities. The multiple guest complexation within the self‐assembled helicates2 aand3 adisplayed large positive cooperative effects, indicating that the first guest complexation preorganizes the rest of the cavities to facilitate a subsequent guest binding. This cooperativity results in the majority‐rules effect in the chiral guest binding for2 aand3 a.
BIII 5‐Arylsubporphyrins and BIII Subporphine
Authors: Kise Koki , Yoshida Kota , Kotani Ryota , Shimizu Daiki , Osuka Atsuhiro
Published: April 2018

Boron(III) 5‐arylsubporphyrins and BIII subporphine are promising precursors for functional BIII subporphyrins bearing asymmetric meso‐substituents. Herein, we report the first synthesis of these molecules. Among many aryl acid chlorides examined, 4‐nitrobenzoyl chloride gave BIII 5‐(4‐nitrophenyl)subporphyrin in 10 % yield in condensation with triethylamine‐tri‐N‐tripyrromethene‐borane. The nitro group of this BIII subporphyrin was reduced with NaBH4 to prepare BIII 5‐(aminophenyl)subporphyrin, which was converted into BIII 5‐phenylsubporphyrin via the corresponding diazonium salt. BIII subporphine was synthesized by condensation of triethyl orthoformate with triethylamine‐tri‐N‐tripyrromethene‐borane. Progressive removal of meso‐phenyl substituents leads to continuous changes in the optical properties, whereas the BIII subporphine deviates from this trend in some properties.
Chiral syntheses of methyl (R)‐2‐Sulfanylcarboxylic esters and acids with optical purity determination using HPLC
Authors: Sasaki Ryosuke , Tanabe Yoo
Published: April 2018

Accessible chiral syntheses of 3 types of (R)‐2‐sulfanylcarboxylic esters and acids were performed: (R)‐2‐sulfanylpropanoic (thiolactic) ester (53%, 98%ee) and acid (39%, 96%ee), (R)‐2‐sulfanylsucciinic diester (59%, 96%ee), and (R)‐2‐mandelic ester (78%, 90%ee) and acid (59%, 96%ee). The present practical and robust method involves (i) clean SN2 displacement of methanesulfonates of (S)‐2‐hydroxyesters by using commercially available AcSK with tris(2‐[2‐methoxyethoxy])ethylamine and (ii) sufficiently mild deacetylation. The optical purity was determined by the corresponding (2R,5R)‐trans‐thiazolidin‐4‐one and (2S,5R)‐cis‐thiazolidin‐4‐one derivatives based on accurate high‐performance liquid chromatography analysis with high‐resolution efficiency. Compared with the reported method utilizing AcSCs (generated from AcSH and CsCO3), the present method has several advantages, that is, the use of odorless AcCOSK reagent, reasonable reaction velocity, isolation procedure, and accurate, reliable optical purity determination.

The use of accessible AcSK has advantages because of easy‐to‐handle odorless and hygroscopic solid that can be used in a bench‐top procedure. The Ti(OiPr)4 catalyst promoted smooth trans‐cyclo‐condensation to afford (2R,5R)‐trans‐thiazolidin‐4‐one formation of (R)‐2‐sulfanylcarboxylic esters with available N‐(benzylidene)methylamine under neutral conditions without any racemization, whereas (2S,5R)‐cis‐thiazollidin‐4‐ones were obtained via cis‐cyclo‐condensation and no catalysts. Direct high‐performance liquid chromatography analysis of methyl (R)‐mandelate was also performed; however, the resolution efficiency was inferior to that of the thaizolidin‐4‐one derivatizations.
Managing work and cancer treatment: Experiences among survivors of hematological cancer
Authors: Thomson Maria D. , Siminoff Laura A.
Published: April 2018

BACKGROUND

The current study was performed to characterize the employment status of survivors of hematological cancer who have an informal caregiver from the time of diagnosis through the first 6 months of treatment.

METHODS

Using a mixed methods approach, semistructured interviews with survivors of hematological cancer were conducted within 6 months of the initiation of cancer treatment. Interviews assessed cancer treatment status, barriers and facilitators to employment, financial and insurance status, and relationship with the primary caregiver. These results are part of a longitudinal study of cancer survivors and informal caregivers.

RESULTS

A total of 171 patients were enrolled. Within 6 months of beginning cancer treatments, approximately 35% were no longer employed. Reasons to remain employed included financial need, employee benefits, and a sense of purpose and normalcy. Employer accommodations and supportive colleagues facilitated continued employment. Logistic regression analysis demonstrated that having a higher household income, a desire to work, nonphysical job tasks, and congruent survivor‐caregiver communication were associated with greater odds of remaining employed.

CONCLUSIONS

Within 6 months of initiating cancer treatment, the majority of survivors of hematological cancer had maintained employment. Because of the limitations imposed by the physical stress of cancer treatments, as well as the need to maintain employment to continue receiving employee benefits to cover such treatments, survivors of hematological cancer likely would benefit from employment accommodations that are sensitive to their unique needs. Cancer 2018;124:2824‐2831. © 2018 American Cancer Society
Racial disparities in postmastectomy breast reconstruction: National trends in utilization from 2005 to 2014
Authors: Epstein Sherise , Tran Bao N. , Cohen Justin B. , Lin Samuel J. , Singhal Dhruv , Lee Bernard T.
Published: April 2018

BACKGROUND

Evidence of racial disparities in the receipt of postmastectomy breast reconstruction is well documented. The objective of this study was to describe trends in racial disparities overall and by reconstructive technique.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was used to identify women who underwent mastectomy and/or breast reconstruction from 2005 to 2014. Patient demographics were recorded, and cases were grouped by reconstructive status and technique. Trends were assessed with the Cochran‐Armitage test and the index of disparity.

RESULTS

Over the study period, 92,960 postmastectomy patients were identified (77,049 white women, 10,396 black women, 4939 Asian women, and 576 Native American women), of whom 46,931 underwent reconstruction. Of these, 7692 women underwent autologous reconstructions (3913 free flaps and 3696 pedicled flaps). From 2005 to 2014, receipt of breast reconstruction by postmastectomy patients rose from 33.2% to 60.0%, receipt of autologous reconstruction by patients who underwent breast reconstruction fell from 30.4% to 15.9%, and receipt of free‐flap reconstruction by patients who underwent autologous reconstruction rose from 15.0% to 70.8%. These trends were significant in all racial subgroups (P < .001), except for Native Americans (P = .269). The index of disparity decreased from 51.4% to 22.6% for overall receipt of breast reconstruction, decreased from 10.7% to 7.0% for tissue expander and implant‐based reconstruction, increased from 18.0% to 27.3% for autologous reconstruction, and decreased from 66.7% to 4.3% for free‐flap reconstruction.

CONCLUSIONS

The use of postmastectomy breast reconstruction is steadily rising in the United States. Racial disparities persist, but progress has been made. Further efforts are needed to reduce racial disparities. Cancer 2018;124:2774‐2784. © 2018 American Cancer Society