bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bismuth‐Mediated Diastereoselective Allylation Reaction of Carbonyl Compounds with Cyclic Allylic Halides or Cinnamyl Halide
Authors: Liu Xuan‐Yu , Cheng Bu‐Qing , Guo Yi‐Cong , Chu Xue‐Qiang , Li Yong‐Xin , Loh Teck‐Peng , Shen Zhi‐Liang 
Published: November 2018

AbstractAn efficient diastereoselective allylation of various carbonyl compounds with cyclic allylic halides by using commercially available bismuth powder in the presence of LiI was developed. Among all the metals screened, bismuth was found to be the best mediator for the transformation. The reactions involving various cyclic allylic halides proceeded smoothly at room temperature to produce the desired homoallylic alcohols in good to excellent yields with high diastereoselectivities (>99:1 dr). Reversed diastereoselectivity was obtained when carbonyl substrate (e. g., 2‐pyridinecarboxaldehyde, glyoxylic acid) containing chelating substituent was used in the allylation reaction. In addition, the reactions involving acyclic (E)‐cinnamyl bromide as substrate worked equally well with high diastereocontrol.magnified image
Dendrimer‐Stabilized Gold Nanoflowers Embedded with Ultrasmall Iron Oxide Nanoparticles for Multimode Imaging–Guided Combination Therapy of Tumors
Authors: Lu Shiyi , Li Xin , Zhang Jiulong , Peng Chen , Shen Mingwu , Shi Xiangyang 
Published: November 2018

AbstractDevelopment of multifunctional theranostic nanoplatforms with improved diagnostic sensitivity and therapeutic efficiency of tumors still remains a great challenge. A unique multifunctional theranostic nanoplatform based on generation 5 (G5) poly(amidoamine) dendrimer–stabilized gold nanoflowers (NFs) embedded with ultrasmall iron oxide (USIO) nanoparticles (NPs) for multimode T1‐weighted magnetic resonance (MR)/computed tomography (CT)/photoacoustic (PA) imaging–guided combination photothermal therapy (PTT) and radiotherapy (RT) of tumors is reported here. G5 dendrimer–stabilized Au NPs and citric acid–stabilized USIO NPs are separately prepared, the two particles under a certain Fe/Au molar ratio are mixed to form complexes, the complexes are exposed to Au growth solution to form NFs via a seed–mediated manner, and the remaining dendrimer terminal amines are acetylated. The formed dendrimer‐stabilized Fe3O4/Au NFs (for short, Fe3O4/Au DSNFs) have a mean diameter of 99.8 nm, display good colloidal stability and cytocompatibility, and exhibit a near‐infrared absorption feature. The unique structure and composition of the Fe3O4/Au DSNFs endows them with a high r1 relaxivity (3.22 mM−1 s−1) and photothermal conversion efficiency (82.7%), affording their uses as a theranostic nanoplatform for multimode MR/CT/PA imaging and combination PTT/RT of tumors with improved therapeutic efficacy, which is important for translational nanomedicine applications.
Stabilizing Li–S Battery Through Multilayer Encapsulation of Sulfur
Authors: Ansari Younes , Zhang Sonia , Wen Bohua , Fan Frank , Chiang Yet‐Ming 
Published: November 2018

AbstractAdvancements in portable electronic devices and electric powered transportation has drawn more attention to high energy density batteries, especially lithium–sulfur batteries due to the low cost of sulfur and its high energy density. However, the lithium–sulfur battery is still quite far from commercialization mostly because of incompatibility between all major components of the battery—the cathode, anode, and electrolyte. Here a methodology is demonstrated that shows promise in significantly improving battery stability by multilayer encapsulation of sulfur particles, while using conventional electrolytes, which allows a long cycle life and an improved Coulombic efficiency battery at low electrolyte feeding. The multilayer encapsulated sulfur battery demonstrates a Coulombic efficiency as high as 98%, when a binder‐free electrode is used. It is also shown that the all‐out self‐discharge of the cell after 168 h can be reduced from 34% in the regular sulfur battery to less than 9% in the battery with the multilayer encapsulated sulfur electrode.
A Maverick Asymmetrical Backbone with Distinct Flanked Twist Angles Modulating the Molecular Aggregation and Crystallinity for High Performance Nonfullerene Solar Cells
Authors: Wang Xunchang , Du Zurong , Dou Keke , Jiang Huanxiang , Gao Chenglin , Han Liangliang , Yang Renqiang 
Published: November 2018

AbstractIn this work, a new asymmetrical backbone thienobenzodithiophene (TBD) containing four aromatic rings is designed, and then four polymers PTBD‐BZ, PTBD‐BDD, PTBD‐FBT, and PTBD‐Tz are synthesized. The planar and high degree of π‐conjugation configuration can guarantee effective charge carrier transport and the distinct flanked dihedral angles between the TBD core and conjugated side chain can subtly regulate the molecular aggregation and crystallinity. The four polymer/3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone)‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]‐dithiophene (ITIC) blending films exhibit predominantly face‐on orientation. The photovoltaic devices based on wide bandgap polymers PTBD‐BZ and PTBD‐BDD achieve power conversion efficiencies (PCEs) as high as 12.02% and 11.39% without any post‐treatment. For the medium bandgap polymers PTBD‐FBT and PTBD‐Tz, the devices also show good PCEs of 10.18% and 11.02% with high VOC of 0.94 and 1.02 V, respectively, which indicates simultaneously achieving a VOC > 1 V and a high JSC is feasible to further improve the PSCs' performance by modifying this new backbone. This work reveals that the versatile asymmetric backbone is an excellent moiety to construct light‐harvesting copolymers and to modulate the microstructure for highly efficient PSCs.
Metal Halide Perovskite Materials for Solar Cells with Long‐Term Stability
Authors: Zhao Ziran , Gu Feidan , Rao Haixia , Ye Senyun , Liu Zhiwei , Bian Zuqiang , Huang Chunhui 
Published: November 2018

AbstractMetal halide perovskite solar cells (PSCs) have emerged as promising candidates for photovoltaic technology with their power conversion efficiencies over 23%. For prototypical organic–inorganic metal halide perovskites, their intrinsic instability poses significant challenges to the commercialization of PSCs. Recently, the scientific community has done tremendous work in composition engineering to develop more robust light‐absorbing layers, including mixed‐ion hybrid perovskites, low‐dimensional hybrid perovskites, and all‐inorganic perovskites. This review provides an overview of the impact of these perovskites on the efficiency and long‐term stability of PSCs.
Excess mortality among Indiana firefighters, 1985‐2013
Authors: Muegge Carolyn M. , Zollinger Terrell W. , Song Yiqing , Wessel Jennifer , Monahan Patrick O. , Moffatt Steven M. 
Published: November 2018

BackgroundFirefighters are exposed to toxic agents increasing their risk for cancer and cardiovascular disease. We examined the odds of cancer and cardiovascular mortality of firefighters relative to a matched group of non‐firefighters from the general population.MethodsFirefighter death records were matched to four non‐firefighter death records on age at time of death, sex, race, ethnicity, and year of death. Exact odds ratios, 95% confidence intervals, and P‐values were calculated using conditional logistic regression to compare groups.ResultsThe odds of death due to malignant cancers was significantly higher for firefighters than non‐firefighters (OR: 1.19; 95%CI 1.08, 1.30). There was no difference in the odds of death for cardiovascular diseases, including ischemic heart disease, between the two groups.ConclusionsThe study suggests the importance of early and effective cancer prevention strategies among firefighters including worksite health promotion programs and incumbent physical activity evaluation.
Hierarchical Microboxes Constructed by SnS Nanoplates Coated with Nitrogen‐Doped Carbon for Efficient Sodium Storage
Authors: Wang Sibo , Fang Yongjin , Wang Xiao , Lou Xiong Wen (David) 
Published: November 2018

AbstractThe design and synthesis of hierarchical microboxes, assembled from SnS nanoplates coated with nitrogen‐doped carbon (NC) as an anode material for sodium‐ion batteries, is demonstrated. The template‐engaged multistep synthesis of the SnS@NC microboxes involves sequential phase transformation, polydopamine coating, and thermal annealing in N2. The SnS@NC composite with two‐dimensional nano‐sized subunits rationally integrates several advantages including shortening the diffusion path of electrons/Na+ ions, improving electric conductivity, and alleviating volume variation of the electrode material. As a result, the SnS@NC microboxes show efficient sodium storage performance with high capacity, good cycling stability, and excellent rate capability.
Conductance Photoswitching of Metal–Organic Frameworks with Embedded Spiropyran
Authors: Garg Shubham , Schwartz Heidi , Kozlowska Mariana , Kanj Anemar Bruno , Müller Kai , Wenzel Wolfgang , Ruschewitz Uwe , Heinke Lars 
Published: November 2018

AbstractConductive metal–organic frameworks (MOFs) as well as smart, stimuli‐responsive MOF materials have attracted considerable attention with respect to advanced applications in energy harvesting and storage as well as in signal processing. Here, the conductance of MOF films of type UiO‐67 with embedded photoswitchable nitro‐substituted spiropyrans was investigated. Under UV irradiation, the spiropyran (SP) reversibly isomerizes to the open merocyanine (MC) form, a zwitterionic molecule with an extended conjugated π‐system. The light‐induced SP–MC isomerization allows for remote control over the conductance of the SP@UiO‐67 MOF film, and the conductance can be increased by one order of magnitude. This research has the potential to contribute to the development of a new generation of photoelectronic devices based on smart hybrid materials.
Red‐ and green‐emitting nano‐clay materials doped with Eu3+ and/or Tb3+
Authors: Santos Hellen S. , Laihinen Tero , Rodrigues Lucas C.V. , Sinkkonen Jari , Mäkilä Ermei , Damlin Pia , Nakamura Liana K.O. , Brito Hermi F. , Hölsä Jorma , Lastusaari Mika 
Published: November 2018

AbstractTrivalent europium (Eu3+) and terbium (Tb3+) ions are important activator centers used in different host lattices to produce red and green emitting materials. The current work shows the design of new clay minerals to act as host lattices for rare earth (RE) ions. Based on the hectorite structure, nano‐chlorohectorites and nano‐fluorohectorites were developed by replacing the OH− present in the hectorite structure with Cl− or F−, thus avoiding the luminescence quenching expected due to the OH− groups. The produced matrices were characterized through X‐ray powder diffraction (XPD), transmission electron microscopy (TEM), FT‐IR, 29Si MAS (magic angle spinning) NMR, nitrogen sorption, thermogravimetry‐differential scanning calorimetry (TGA‐DSC) and luminescence measurements, indicating all good features expected from a host lattice for RE ions. The nano‐clay materials were successfully doped with Eu3+ and/or Tb3+ to yield materials preserving the hectorite crystal structure and showing the related luminescence emissions. Thus, the present work shows that efficient RE3+ luminescence can be obtained from clays without the use of organic ‘antenna’ molecules.
Parenting programmes for parents of children and young people with behavioural difficulties
Authors: Lindsay Geoff 
Published: November 2018

AbstractChildren and young people exhibiting behavioural difficulties present a major challenge not only to parents but also to education and health professionals and to society as a whole. In this paper, I shall address some key issues regarding these parenting programmes, based particularly on a programme of research over 13 years in the Centre for Educational Development, Appraisal and Research at the University of Warwick. This has comprised large‐scale studies across all areas of England, both programmes targeted at parents whose children are presenting or at risk of developing behavioural difficulties: the Parenting Early Intervention Pathfinder and Parenting Early Intervention Programme; and universal programmes aimed at all parents, as a positive contribution to behavioural development across the population: the CANparent trial. All were funded by the Department for Education plus the continuation of the CANparent trial was funded by the Department of Health. In addition, I consider studies that have built on this research to examine the use of parenting programmes with parents of children and young people with special educational needs; and also the effectiveness of programmes during sustained implementation, beyond formal trials and similar research initiatives, that is, as day‐to‐day practice. I show that well‐constructed parenting programmes that are acceptable to parents are effective, that these positive effects on parents can remain over time, and also that the positive effects found in well‐organised trials can be maintained when programmes are delivered by community services as part of their normal practice.
Photocatalytic Hydrodehalogenation for the Removal of Halogenated Aromatic Contaminants
Authors: Wang Yuanyuan , Wei Yan , Song Wenjing , Chen Chuncheng , Zhao Jincai 
Published: November 2018

AbstractThe environmental distribution and bioaccumulation of anthropogenic halogenated aromatic pollutants cause severe health problems. Hydrodehalogenation is an effective route to remove these types of compounds, generating hydrogenated products and halide anions. Photocatalytic systems can provide highly reactive species to break carbon‐halogen bonds, leading to hydrodehalogenation under mild conditions with simple alcohols or amines instead of hazardous stoichiometric reagents. Here, we review significant advances in light‐driven hydrodehalogenation based on different types of photocatalysts for the transformation of halogenated aromatics. We detail the reaction pathways and product distributions. Challenges, key principles and strategies to improve dehalogenation efficiency are also discussed.
Molecule‐Driven Shape Control of Metal Co‐Catalysts for Selective CO2 Conversion Photocatalysis
Authors: Cho Hyunjin , Dong Kim Whi , Yu Jiwon , Lee Sangheon , Lee Doh C. 
Published: November 2018

AbstractIn photocatalysis of CO2 conversion, metal co‐catalysts draw photo‐generated electrons from semiconductor components and act as reaction sites by adsorbing CO2 and its intermediates. Optimization of the metal co‐catalyst structure is indispensable to improving the efficiency of the photocatalyst, which is currently not meeting performance requirements. By performing a series of experiments and simulations, we demonstrate the effect of selective particle shape control of metal co‐catalysts (Au, Ag, Cu and Pt) by the CO2 induced gas ligands (CO2 and CO) on photocatalytic CO2 conversion activity and selectivity. Indeed, facet formation for adsorption of CO2 and CO proves to be an effective way to improve the CO2 conversion activity. In particular, proper interaction between the gas ligand and the metal co‐catalyst surface, realized by strengthening the metal‐CO2 adsorption and weakening the metal‐CO adsorption, is identified as essential factor for increasing the CO2 conversion activity. Pt and Cu, which exhibit relatively strong interaction with gas molecules, have the improved photocatalytic CO2 conversion activity when grown under CO2. In contrast, Au and Ag, which exhibit relatively weak interaction with gas molecules, have the enhanced photocatalytic CO2 conversion activity when grown under CO. This systematic understanding can be a guideline for controlling the metal co‐catalyst surface structure and will maximize the photocatalytic selectivity of the CO2 conversion.
Mechanisms and Beyond: Elucidation of Fluxional Dynamics by Exchange NMR Spectroscopy
Authors: Nikitin Kirill , O'Gara Ryan 
Published: November 2018

AbstractDetailed mechanistic information is crucial to our understanding of reaction pathways and selectivity. Dynamic exchange NMR techniques, in particular 2D exchange spectroscopy (EXSY) and its modifications, provide indispensable intricate information on the mechanisms of organic and inorganic reactions and other phenomena, for example, the dynamics of interfacial processes. In this Review, key results from exchange NMR studies of small molecules over the last few decades are systemised and discussed. After a brief introduction to the theory, the key types of dynamic processes are identified and fundamental examples given of intra‐ and intermolecular reactions, which, in turn, could involve, or not, bond‐making and bond‐breaking events. Following that logic, internal molecular rotation, intramolecular stereomutation and molecular recognition will first be considered because they do not typically involve bond breaking. Then, rearrangements, substitution‐type reactions, cyclisations, additions and other processes affecting chemical bonds will be discussed. Finally, interfacial molecular dynamics and unexpected combinations of different types of fluxional processes will also be highlighted. How exchange NMR spectroscopy helps to identify conformational changes, coordination and molecular recognition processes as well as quantify reaction energy barriers and extract detailed mechanistic information by using reaction rate theory in conjunction with computational techniques will be shown.
Gold‐Catalyzed Facile Synthesis and Crystal Structures of Benzene‐/Naphthalene‐Based Bispentalenes as Organic Semiconductors
Authors: Sekine Kohei , Schulmeister Jürgen , Paulus Fabian , Goetz Katelyn P. , Rominger Frank , Rudolph Matthias , Zaumseil Jana , Hashmi A. Stephen K. 
Published: November 2018

AbstractThe gold‐catalyzed facile synthesis of U‐shaped and S‐shaped bispentalenes is described from easily available tetra(arylethynyl)‐benzenes and ‐naphthalenes. The optoelectronic and transistor properties were also investigated. The selectivity between the U‐shaped and S‐shaped bispentalene isomers can be tuned by the bulkiness of the ligand and the substrates. The S‐shaped naphthalene‐based bispentalene shows a one‐dimensional face‐to‐face packing pattern in solid state and a good hole mobility, indicating that the S‐shaped bispentalene core is highly suitable for transistor applications. The gold‐catalyzed annulation of tetraynes provides a useful protocol in the synthesis of bispentalenes for organic semiconductors.
Cover Picture: Synthesis of Macrocyclic Oligoparaphenylenes Derived from Anthracene Photodimer (Chin. J. Chem. 12/2018)
Authors: Guo Lifeng , Yang Xiaodi , Cong Huan 
Published: November 2018

The cover picture shows a highly warped oligoparaphenylene‐derived “nanoring” prepared employing the anthracene [4+4] photodimer as the core synthon. The macrocyclic compound can further undergo cycloreversion under thermal conditions to afford a carbon nanohoop containing an anthracene moiety. This work demonstrates the synthetic utility of the anthracene photodimerization‐cycloreversion strategy in the context of synthesizing strained conjugated macrocycles. More details are discussed in the article by Cong et al. on page 1135–1138.
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Alcohol septal ablation vs myectomy for symptomatic hypertrophic obstructive cardiomyopathy: Systematic review and meta‐analysis
Authors: Osman Mohammed , Kheiri Babikir , Osman Khansa , Barbarawi Mahmoud , Alhamoud Hani , Alqahtani Fahad , Alkhouli Mohamad 
Published: November 2018

BackgroundSurgical myectomy (SM) and Alcohol septal ablation (ASA) are effective therapies for patients with hypertrophic cardiomyopathy who remain symptomatic despite medical therapy. A plethora of data has recently emerged on the long‐term outcomes of these procedures. We hence sought to perform an updated meta‐analysis comparing both procedures.MethodsStudies reporting long‐term (>3‐years) outcomes of SM and/or ASA were included. The primary endpoint was all‐cause mortality. Secondary endpoints included cardiovascular mortality, sudden cardiac death (SCD), reintervention, and complications including death, pacemaker implantation, and stroke.ResultsTwenty‐two ASA cohorts (n = 4213; follow‐up = 6.6‐years) and 23 SM cohorts (n = 4240; follow‐up = 6.8‐years) were included. Septal myectomy was associated with higher periprocedural mortality and stroke (2% vs 1.2%, P = 0.009 and 1.5% vs 0.8% P = 0.013, respectively), but ASA was associated with more need of pacemaker (10% vs 5%, P < 0.001). During long‐term follow‐up, all‐cause mortality, cardiovascular mortality, and sudden cardiac death rates were 1.5%, 0.4%, and 0.3% per person‐year in the ASA group and 1.1%, 0.5%, and 0.3% per person‐year in the SM group (P = 0.21, P = 0.53, P = 0.43), respectively. Repeat septal reduction intervention(s) were more common after ASA (11% vs 1.5%, P < 0.001).ConclusionCompared with SM, ASA is associated with lower periprocedural mortality and stroke but higher rates of pacemaker implantations and reintervention. However, there was no difference between ASA and SM with regards to long‐term all‐cause mortality, cardiovascular mortality, or SCD.
Ten‐year change in neighborhood socioeconomic status and colorectal cancer
Authors: Zhang Dong , Matthews Charles E. , Powell‐Wiley Tiffany M. , Xiao Qian 
Published: November 2018

BackgroundA growing body of research has demonstrated that individuals who live in neighborhoods with more severe socioeconomic deprivation may have higher risks for colorectal cancer (CRC). However, previous studies have examined neighborhood socioeconomic status (SES) at only 1 point in time, and it is unclear whether changes in neighborhood SES also can influence the risks of CRC.MethodsCox regression analysis was used to examine different trajectories of change in neighborhood SES over 10 years in relation to the incidence of CRC among 266,804 participants (ages 51‐70 years) in the National Institutes of Health‐AARP Diet and Health Study. Eligible participants reported living in the same neighborhood at baseline (1995‐1996) and from 2004 to 2006 according to a follow‐up questionnaire. Changes in neighborhood SES were measured between 1990 and 2000 by SES indices derived from Census data. Neighborhoods were grouped into 4 categories based on median SES indices in 1990 and 2000 (low‐low, low‐high, high‐low, and high‐high).ResultsCompared with residents whose neighborhoods were in the higher SES group at both time points (reference category), those whose neighborhoods were consistently in the low SES group had a 7% higher risk of developing CRC (hazard ratio, 1.07; 95% confidence interval, 1.00‐1.14). Moreover, the risk of CRC was 15% higher (hazard ratio, 1.15; 95% confidence interval, 1.02‐1.28) for those living in neighborhoods with decreasing SES (high‐low) over time.ConclusionsThe current findings suggest that exposure to consistently low SES neighborhoods and/or a decrease in neighborhood SES over a period of time may be associated with higher risks of CRC.
Self‐Assembly Synthesis of Mulberry‐Like Fe/N/S‐Doped Highly Porous Carbon Materials: Efficient and Stable Catalysts for Oxygen Reduction Reaction
Authors: Liu Wenqi , Xu Dongyan , Li Xiaojin 
Published: November 2018

AbstractIn this work, unique structures of mulberry‐like Fe/N/S‐doped nanoporous carbon materials (NCMs) are synthesized via a simple self‐assembly assisted process. The Fe2+‐mediated polymerization of dopamine (DA) and further interaction with triblock copolymer F127 micelles induce the formation of mulberry‐like Fe/PDA/F127 structures. After carbonization, the Fe/N/S‐doped NCMs are obtained with a highly porous structure and large Brunauer‐Emmett‐Teller (BET) surface area of 913.2 m2 g−1. Moreover, DA and iron salt introduce active sites, such as Sp2 C, graphitic N, pyridinic N, Fe−Nx, C−S−C, etc. Benefiting from these unique structural features and chemical compositions, the optimized Fe/N/S‐doped NCMs exhibit enhanced electrocatalytic activity and excellent durability for oxygen reduction reaction (ORR) compared with commercial Pt/C catalyst. These studies provide not only a new synthesis method for heteroatom‐doped NCMs, but also a platform for various applications.