bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal prediction of the South Pacific Convergence Zone in the austral wet season
Authors: Charles A. N. , Brown J. R. , Cottrill A. , Shelton K. L. , Nakaegawa T. , Kuleshov Y.
Published: October 2014

The position and orientation of the South Pacific Convergence Zone (SPCZ), modulated by the El Niño‐Southern Oscillation (ENSO), determine many of the potentially predictable interannual variations in rainfall in the South Pacific region. In this study, the predictability of the SPCZ in austral summer is assessed using two coupled (ocean‐atmosphere) global circulation model (CGCM)‐based seasonal prediction systems: the Japan Meteorological Agency's Meteorological Research Institute Coupled Ocean‐Atmosphere General Circulation Model (JMA/MRI‐CGCM) and the Australian Bureau of Meteorology's Predictive Ocean‐Atmosphere Model for Australia (POAMA‐M24). Forecasts of austral summer rainfall, initialized in November are assessed over the period 1980–2010. The climatology of CGCM precipitation in the SPCZ region compares favorably to rainfall analyses over subsets of years characterizing different phases of ENSO. While the CGCMs display biases in the mean SPCZ latitudes, they reproduce interannual variability in austral summer SPCZ position indices for forecasts out to 4 months, with temporal correlations greater than 0.6. The summer latitude of the western branch of the SPCZ is predictable with correlations of the order of 0.6 for forecasts initialized as early as September, while the correlation for the eastern branch only exceeds 0.6 for forecasts initialized in November. Encouragingly, the models are able to simulate the large displacement of the SPCZ during zonal SPCZ years 1982–1983, 1991–1992, and 1997–1998.
Impact of resolution on simulation of closed mesoscale cellular convection identified by dynamically guided watershed segmentation
Authors: Martini Matus N. , Gustafson William I. , Yang Qing , Xiao Heng
Published: October 2014

Organized mesoscale cellular convection (MCC) is a common feature of marine stratocumulus clouds that forms in response to interactions among dynamic, microphysical, and radiative processes at the mesoscale. Cloud resolving models begin to resolve some of these processes, but using high resolutions is extremely costly. To understand the impact of limited resolution on MCC, we use the Weather Research and Forecasting model with chemistry and fully coupled cloud‐aerosol interactions to simulate MCC over the southeast Pacific during the Variability of the American Monsoon Systems Ocean‐Cloud‐Atmosphere‐Land Study Regional Experiment (VOCALS‐REx). A suite of experiments with 3 and 9 km grid spacing indicates that the simulations with finer grid spacing have smaller liquid water paths and cloud fractions, while cloud tops are higher. The observed diurnal cycle is reasonably well simulated. To isolate organized MCC characteristics, we develop a new automated method that uses the watershed segmentation combining the detection of cloud boundaries with coincident vertical velocities. This ensures that the detected cloud fields are dynamically consistent for closed MCC, a common feature within the VOCALS‐REx region. We demonstrate that the 3 km simulation is able to reproduce the scaling between horizontal cell size and boundary layer depth seen in satellite observations for the conditions of 900–1400 m deep boundary layers. However, the 9 km simulation is unable to resolve smaller circulations corresponding to shallower boundary layers, instead producing MCC with an invariant horizontal scale for all simulated boundary layers depths. The results demonstrate that the grid spacing needed for proper simulation of the MCC structure in marine stratocumulus regions depends on the boundary layer depth.
Observed and projected urban extreme rainfall events in India
Authors: Ali Haider , Mishra Vimal , Pai D. S.
Published: October 2014

We examine changes in extreme rainfall indices over 57 major urban areas in India under the observed (1901–2010) and projected future climate (2010–2060). Between 1901 and 2010, only four out of the total 57 urban areas showed a significant (p‐value <0.05) increasing trend in the monsoon maximum rainfall (MMR). Time‐varying trends for the various rainfall indices exhibited that only a few urban areas experienced significant increases in the extreme rainfall indices for the different periods. Moreover, rainfall maxima for 1–10 day durations and at 100 year return period did not change significantly over the majority of urban areas in the post‐1955 period. Results do not indicate any significant change (p > 0.05) in the pooled mean and distribution of the extreme rainfall indices for the pre‐ and post‐1983 periods revealing an insignificant role of urbanization on rainfall extremes in the major urban areas in India. We find that at the majority of urban areas changes in the extreme rainfall indices are driven by large scale climate variability. Regional Climate Models (RCMs) that participated in the CORDEX‐South Asia program showed a significant bias in the monsoon maximum rainfall and rainfall maxima at 100 year return period for the majority of urban areas. For instance, most of the models fail to simulate rainfall maxima within ±10% bias, which can be considered appropriate for a storm water design at many urban areas. Rainfall maxima at 1–3 day durations and 100 year return period is projected to increase significantly under the projected future climate at the majority of urban areas in India. The number of urban areas with significant increases in rainfall maxima under the projected future climate is far larger than the number of areas that experienced significant changes in the historic climate (1901–2010), which warrants a careful attention for urban storm water infrastructure planning and management.
Statistical studies on Mars atmospheric sputtering by precipitating pickup O+: Preparation for the MAVEN mission
Authors: Wang Yung‐Ching , Luhmann Janet G. , Fang Xiaohua , Leblanc François , Johnson Robert E. , Ma Yingjuan , Ip Wing‐Huen
Published: October 2014

With the upcoming MAVEN mission, the role of escape in the evolution of the Martian atmosphere is investigated in more detail. This work builds on our previous modeling of the atmospheric impact of the pickup O+sputtering effects for various solar wind parameters, solar EUV intensities, and the surface crustal field distributions. Relationships between the incident ion properties and the ejected hot neutral components, often referred to as atmospheric sputtering, are derived for application to proposed MAVEN ion spectrometer measurements of precipitating O+. We show how our simulation results can be used to constrain the sputtering effects under present conditions and to interpolate toward estimates of sputtering efficiencies occurring in earlier epochs. Present‐day sputtering under typical circumstance is estimated to be weak but possibly detectable as an exospheric enhancement. The ultimate goal of estimating the importance of atmospheric sputtering effects on the evolution of the Martian atmosphere can be better deduced by the combining MAVEN measurements with models and the sputtering response relations derived here.
Steady state estimation of soil organic carbon using satellite‐derived canopy leaf area index
Authors: Fang Yilin , Liu Chongxuan , Huang Maoyi , Li Hongyi , Leung L. Ruby
Published: October 2014

Estimation of soil organic carbon (SOC) stock using models typically requires long term spin‐up of the carbon‐nitrogen (CN) models, which has become a bottleneck for global modeling. We report a new numerical approach to estimate global SOC stock that can alleviate long spin‐up. The approach uses satellite‐based canopy leaf area index (LAI) and takes advantage of a reaction‐based biogeochemical module—Next Generation BioGeoChemical Module (NGBGC) that was recently developed and incorporated in version 4 of the Community Land Model (CLM4). Although NGBGC uses the same CN mechanisms as in CLM4CN, it can be easily configured to run prognostic or steady state simulations. The new approach was applied at point and global scales and compared with SOC derived from spin‐up by running NGBGC in the prognostic mode, and SOC from the Harmonized World Soil Database (HWSD). The steady state solution is comparable to the spin‐up value when the satellite LAI is close to that from the spin‐up solution, and largely captured the global variability of the HWSD SOC across the different dominant plant functional types (PFTs). The correlation between the simulated and HWSD SOC was, however, weak at both point and global scales, suggesting the needs for improving the biogeochemical processes described in CLM4 and updating HWSD. Besides SOC, the steady state solution also includes all other state variables simulated by a spin‐up run, which makes the tested approach a promising tool to efficiently estimate global SOC distribution and evaluate and compare multiple aspects simulated by different CN mechanisms in the model.
Synthesis of Fused Quinoline and Quinoxaline Derivatives Enabled by Domino Radical Triple Bond Insertions
Authors: Sun Xiaoyang , Li Jiahong , Ni Yunpeng , Ren Daan , Hu Zhentao , Yu Shouyun
Published: October 2014

A practical and environmentally friendly strategy for the preparation of fused quinoline and quinoxaline derivatives has been developed, enabled by domino radical triple bond insertions. These reactions have very high regioselectivity and can be carried out under mild conditions in good to excellent chemical yields.
Scanning Electrochemical Microscopy of Individual Catalytic Nanoparticles
Authors: Sun Tong , Yu Yun , Zacher Brian J. , Mirkin Michael V.
Published: October 2014

Electrochemistry at individual metal nanoparticles (NPs) can provide new insights into their electrocatalytic behavior. Herein, the electrochemical activity of single AuNPs attached to the catalytically inert carbon surface is mapped by using extremely small (≥3 nm radius) polished nanoelectrodes as tips in the scanning electrochemical microscope (SECM). The use of such small probes resulted in the spatial resolution significantly higher than in previously reported electrochemical images. The currents produced by either rapid electron transfer or the electrocatalytic hydrogen evolution reaction at a single 10 or 20 nm NP were measured and quantitatively analyzed. The developed methodology should be useful for studying the effects of nanoparticle size, geometry, and surface attachment on electrocatalytic activity in real‐world application environment.
Hemodialysis membrane surface chemistry as a barrier to lipopolysaccharide transfer
Authors: Madsen Ben , Britt David W. , Ho Chih‐Hu , Henrie Michael , Ford Cheryl , Stroup Eric , Maltby Brent , Olmstead Doug , Andersen Marion
Published: October 2014

During hemodialysis bacterial lipopolysaccharide (LPS) in contaminated dialysate solution may translocate across the hollow fiber membrane (HFM) to a patient's blood, resulting in fever and possible systemic shock. This study investigates LPS transfer across, and adsorption within, native and modified Fresenius Optiflux® F200NRepolysulfone (PS)/polyvinyl pyrrolidone (PVP) HFMs. Modifications include varied PVP content, addition of a PS‐poly(ethylene glycol) copolymer (PS‐PEG), and bleach sterilization. Under clinically relevant flow conditions LPS from >400 EU mL−1spiked dialysate is not detected (<0.1 EU mL−1) in the lumens of native fibers, but is detected to varying degrees (0.2–15 EU mL−1) in the lumens of the modified fibers. Fluorescently labeled LPS predominantly adsorbs near the lumen of all membranes except the PS‐PEG containing membrane, where LPS localizes on the outer wall. Thus, addition of PS‐PEG may entrap LPS in the HFM spongy matrix, away from the blood‐contacting fiber lumen. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 41550.
Normal probability plots with confidence
Authors: Chantarangsi Wanpen , Liu Wei , Bretz Frank , Kiatsupaibul Seksan , Hayter Anthony J. , Wan Fang
Published: October 2014

Normal probability plots are widely used as a statistical tool for assessing whether an observed simple random sample is drawn from a normally distributed population. The users, however, have to judge subjectively, if no objective rule is provided, whether the plotted points fall close to a straight line. In this paper, we focus on how a normal probability plot can be augmented by intervals for all the points so that, if the population distribution is normal, then all the points should fall into the corresponding intervals simultaneously with probability . These simultaneous probability intervals provide therefore an objective mean to judge whether the plotted points fall close to the straight line: the plotted points fall close to the straight line if and only if all the points fall into the corresponding intervals. The powers of several normal probability plot based (graphical) tests and the most popular nongraphical Anderson‐Darling and Shapiro‐Wilk tests are compared by simulation. Based on this comparison, recommendations are given in Section 3 on which graphical tests should be used in what circumstances. An example is provided to illustrate the methods.
Meta-analysis of gut barrier dysfunction in patients with acute pancreatitis
Authors: Wu L M , Sankaran S J , Plank L D , Windsor J A , Petrov M S
Published: October 2014

Background

The gut is implicated in the pathogenesis of acute pancreatitis but there is discrepancy between individual studies regarding the prevalence of gut barrier dysfunction in patients with acute pancreatitis. The aim of this study was to determine the prevalence of gut barrier dysfunction in acute pancreatitis, the effect of different co-variables, and changes in gut barrier function associated with the use of various therapeutic modalities.

Methods

A literature search was performed using PRISMA and MOOSE guidelines. Summary estimates were presented as pooled prevalence of gut barrier dysfunction and the associated 95 per cent c.i.

Results

A total of 44 prospective clinical studies were included in the systematic review, of which 18 studies were subjected to meta-analysis. The pooled prevalence of gut barrier dysfunction was 59 (95 per cent c.i. 48 to 70) per cent; the prevalence was not significantly affected by disease severity, timing of assessment after hospital admission or type of test used, but showed a statistically significant association with age. Overall, nine of 13 randomized clinical trials reported a significant improvement in gut barrier function following intervention compared with the control group, but only three of six studies that used standard enteral nutrition reported a statistically significant improvement in gut barrier function after intervention.

Conclusion

Gut barrier dysfunction is present in three of five patients with acute pancreatitis, and the prevalence is affected by patient age but not by disease severity. Clinical studies are needed to evaluate the effect of enteral nutrition on gut function in acute pancreatitis.
Influence of visual force feedback on tissue handling in minimally invasive surgery
Authors: Rodrigues S P , Horeman T , Sam P , Dankelman J , van den Dobbelsteen J J , Jansen F-W
Published: October 2014

Background

Force feedback might improve surgical performance during minimally invasive surgery. This study sought to determine whether training with force feedback shortened the tissue-handling learning curve, and examined the influence of real-time visual feedback compared with postprocessing feedback.

Methods

Medical students without experience of minimally invasive surgery were randomized into three groups: real-time force feedback, postprocessing force feedback and no force feedback (control). All performed eight suturing tasks consecutively, of which the first and eighth were the premeasurement and postmeasurement tasks respectively (no feedback). Depending on randomization, either form of feedback was given during the second to seventh task. Time, mean force non-zero and maximum force were measured with a force sensor. Results of the groups were compared with one-way ANOVA, and intragroup improvement using a paired-samples t test.

Results

A total of 72 students took part. Both intervention groups used significantly lower interaction forces than the control group during the knot-tying phase of the postmeasurement task and improved their interaction forces significantly during the knot-tying phase. The form of feedback did not influence its effectiveness.

Conclusion

The tissue-handling skills of medical students improved significantly when they were given force feedback of their performance. This effect was seen mainly during the knot-tying phase of the suturing task.
Isolation and genetic analysis of an environmental bacteriophage: A 10‐session laboratory series in molecular virology
Authors: Williamson Ryan P. , Barker Brent T. , Drammeh Hamidou , Scott Jefferson , Lin Joseph
Published: October 2014

Bacterial viruses, otherwise known as bacteriophage (or phage), are some of the most abundant viruses found in the environment. They can be easily isolated from water or soil and are ideal for use in laboratory classrooms due to their ease of culture and inherent safety. Here, we describe a series of 10 laboratory exercises where students collect, isolate, and purify the genome of an environmental phage. Once the genome has been extracted, students then clone a fragment of their isolated phage genome into a plasmid and analyze its sequence to identify the phage in their original isolate. These exercises have been carefully designed to apply foundational concepts that will expose students to basic skills in microbiology, molecular biology, and bioinformatics. © 2014 by The International Union of Biochemistry and Molecular Biology, 42(6):480–485, 2014.
Under‐Fives Child Mortality and Child Abuse‐Related Deaths in the Former USSR: Is there an Under‐Reporting of Abuse‐Related Deaths?
Authors: Pritchard Colin , Mirza Saalim
Published: October 2014

The study explores the former Union of Soviet Socialist Republics (USSR) countries’ under‐fives child mortality rates (CMR) and child abuse‐related deaths (CARD) since the end of the Soviet Union, and asks whether there has been an ‘under‐reporting’ of CARD? World Health Organization under‐fives mortality rates per million (pm) were extracted for 1988–90 and compared with 2008–10 for CMR and confirmed and possible CARD.

Possible CARD are undetermined deaths (UnD) and ill‐defined signs and symptoms (IDSS) deaths as these categories have been linked to under‐reporting of CARD. CMR and CARD odds ratios were calculated and correlated to determine the possible under‐reporting of CARD. Seven countries met the United Nations International Children's Education Fund (UNICEF) objective of reducing CMR; five halving their previous USSR rate. The Russian CARD rate at 29 pm is the highest, but six countries’ rates were less than ten pm. UnD increased in Kazakhstan 13‐fold, Belarus eight times, Ukraine seven times and Russia more than four times. IDSS deaths trebled in Belarus, and rose more than 25 per cent in Kazakhstan, Georgia and Ukraine. CARD significantly correlated with UnD but not with CMR.

Odds ratios of CMR to all three CARD categories were substantial, more than 4.1:1 in Belarus, Kazakhstan, Russia and Ukraine, indicating possible under‐reporting of CARD.

Despite CMR improvements, this first‐ever study of the former USSR countries should alert the authorities of Belarus, Kazakhstan, the Russian Federation and Ukraine to the extent of possible child abuse. Copyright © 2014 John Wiley & Sons, Ltd.

‘Seven countries met the UNICEF objective of reducing CMR

Key Practitioner Messages:

This first‐ever study of child mortality and child abuse deaths in the former USSR found improvements in child mortality but unrecognised child protection issues.

Child homicides ostensibly fell in every country but Russia.

Major rises in undetermined and ill‐defined deaths in Belarus, Kazakhstan, Russia and Ukraine are indicative of under‐reporting but did not occur in the other former USSR countries.

There is an urgent need to focus upon violence against children as either child abuse is not recognised, or it is being deliberately ignored.

‘Either child abuse is not recognised, or it is being deliberately ignored’
Current Parental Attitudes Towards Upbringing Practices in Finland and Sweden 30 Years after the Ban on Corporal Punishment
Authors: Ellonen Noora , Jernbro Carolina , Janson Staffan , Tindberg Ylva , Lucas Steven
Published: October 2014

Thirty years have now passed since Sweden and Finland, as the first countries in the world, enacted national legislation against corporal punishment. This study examines the current attitudes towards corporal punishment among Finnish and Swedish parents of newborn to 12‐year‐old children. Differences between the countries in parents’ attitudes towards upbringing practices in relation to socio‐demographic background factors were also analysed. The study was based on identical survey data collected separately in Finland and Sweden in 2011 and later merged for analysis. The survey included questions regarding parental behaviour and attitudes towards upbringing practices. Data were analysed using univariate tests (chi‐2) and logistic regression. The analysis showed that a significantly larger proportion of Finnish parents approved of slapping or hitting their children compared to Swedish parents (OR = 6.20). Swedish parents, on the other hand, approved of shaking more than Finnish parents (OR = 0.54). Furthermore, a larger proportion of Finnish parents had positive attitudes towards non‐violent types of punishments compared to Swedish parents. The socio‐demographic background factors did not explain the differences between the countries. Cultural factors that may plausibly influence these attitudes are discussed. Copyright © 2014 John Wiley & Sons, Ltd.

Key Practitioner Messages:

Even in countries with a long‐standing ban on corporal punishment of children, there is reason to elucidate parents’ attitudes.

It is important to understand cultural factors, especially views on violent behaviour.

Even when a majority of parents have some knowledge about children's rights, its full meaning needs to be promoted through a general programme.

Preventive work against corporal punishment needs to take parents’ attitudes into account.

Children's right to a non‐violent childhood should be advocated at all levels of society.

‘A significantly larger proportion of Finnish parents approved of slapping or hitting their children compared to Swedish parents’

‘Children's right to a non‐violent childhood should be advocated at all levels of society’
Synthesis of LiNi0.5Mn1.5O4 Hollow Microspheres and Their Lithium‐Storage Properties
Authors: Luo Haifeng , Nie Ping , Shen Laifa , Li Hongshen , Deng Haifu , Zhu Yaoyao , Zhang Xiaogang
Published: October 2014

High‐voltage LiNi0.5Mn1.5O4 hollow microspheres have been synthesized through a facile solid‐state method. X‐ray diffraction and scanning electron microscopy results reveal that the as‐prepared LiNi0.5Mn1.5O4 microspheres are constructed with nanometer‐sized primary particles. The effects of the precursors on the morphologies and electrochemical properties of LiNi0.5Mn1.5O4 materials are systematically investigated. Electrochemical test results demonstrate that the materials with large porosity and smaller second particles exhibit higher reversible capacity as well as better cycle stability and rate capacities. LiNi0.5Mn1.5O4 prepared from MnCO3 precursors delivers high reversible capacities of 135.5, 147.5, and 132.1 mAh g−1 at 0.1, 0.5, and 2 C, respectively. Even at a high rate of 5 C, the electrode retains 93.4 % of the initial capacity at 0.1 C. Moreover, the electrode shows excellent cycle stability with a discharge capacity of 110 mAh g−1 at 1 C after 80 cycles at elevated temperature. The extremely attractive electrochemical properties are closely related to the unique structure and chemistry of the synthesized material.
Enhancing the Electrochemical and Electronic Performance of CVD‐Grown Graphene by Minimizing Trace Metal Impurities
Authors: Iost Rodrigo M. , Crespilho Frank N. , Zuccaro Laura , Yu Hak Ki , Wodtke Alec M. , Kern Klaus , Balasubramanian Kannan
Published: October 2014

The presence of unwanted impurities in graphene is known to have a significant impact on its physical and chemical properties. Similar to carbon nanotubes, any trace metals present in graphene will affect the electrocatalytic properties of the material. Here, we show by direct electroanalysis that traces of copper still remain in transferred CVD (chemical vapor deposition)‐grown graphene (even after the usual copper etching process) and strongly influence its electrochemical properties. Subsequently, we use a real‐time electrochemical etching procedure to remove more than 90 % of the trace metal impurities, with a clear improvement in both the electrochemical and electronic‐transport properties of monolayer graphene.
Aromaticity and Stability of Azaborines
Authors: Baranac‐Stojanović Marija
Published: October 2014

The influence of the relative boron and nitrogen positions on aromaticity of the three isomeric 1,2‐, 1,3‐, and 1,4‐azaborines has been investigated by computing the extra cyclic resonance energy, NICS(0)πzz index and by visualizing the π‐electron (de)shielding pattern as a response of the π system to a perpendicular magnetic field. The origin of the known stability trend, in which the 1,2‐/1,3‐isomer is the most/least stable, was examined by using an isomerization energy decomposition analysis. The 1,3‐arrangement of B and N atoms creates a charge separation in the π‐electron system, which was found to be responsible for the lowest stability of 1,3‐azaborine. This charge separation can, in turn, be considered as a driving force for the strongest cyclic π‐electron delocalization, making this same isomer the most aromatic. Despite the well‐known fact that the BN bond attenuates electron delocalization due to large electronegativity difference between the atoms, the 1,4‐B,N relationship reduces aromaticity to a greater extent by making the π‐electron delocalization more one‐directional (from N to B) than cyclic. Thus, 1,4‐azaborine was found to be the least aromatic. Its lower stability with respect to the 1,2‐isomer was explained by the larger exchange repulsion.
The ortho‐Substituent Effect on the Ag‐Catalysed Decarboxylation of Benzoic Acids
Authors: Grainger Rachel , Cornella Josep , Blakemore David C. , Larrosa Igor , Campanera Josep M.
Published: October 2014

A combined experimental and computational investigation on the Ag‐catalysed decarboxylation of benzoic acids is reported herein. The present study demonstrates that a substituent at the ortho position exerts dual effects in the decarboxylation event. On one hand, ortho‐substituted benzoic acids are inherently destabilised starting materials compared to their meta‐ and para‐substituted counterparts. On the other hand, the presence of an ortho‐electron‐withdrawing group results in an additional stabilisation of the transition state. The combination of both effects results in an overall reduction of the activation energy barrier associated with the decarboxylation event. Furthermore, the Fujita–Nishioka linear free energy relationship model indicates that steric bulk of the substituent can also exert a negative effect by destabilising the transition state of decarboxylation.
Current Status on Plastic Scintillators Modifications
Authors: Bertrand Guillaume H. V. , Hamel Matthieu , Sguerra Fabien
Published: October 2014

Recent developments of plastic scintillators are reviewed, from 2000 to March 2014, distributed in two different chapters. First chapter deals with the chemical modifications of the polymer backbone, whereas modifications of the fluorescent probe are presented in the second chapter. All examples are provided with the scope of detection of various radiation particles. The main characteristics of these newly created scintillators and their detection properties are given.
Dramatic Shape Modulation of Surfactant/Diacetylene Microstructures at the Air–Water Interface
Authors: Jiang Hao , Jelinek Raz
Published: October 2014

Langmuir monolayers constitute a powerful platform for self‐assembly and organization of amhiphilic molecules. Controlling the structural features of condensed domains formed within Langmuir monolayers, however, is a challenging task. The formation of remarkably diverse condensed microstructures is demonstrated in binary monolayers comprising of a surfactant (octadecylmelamine) and a diacetylene monomer. The mole ratio between the two constituents and composition of the aqueous subphases (specifically pH and which dissolved metal ions are present) dramatically modulated the shapes and dimensions of microstructures formed at the air–water interface. The self‐assembled microstructures could be transferred from the water surface onto solid substrates, and subsequently further served as templates for gold coating, yielding electrically conductive microwires.
Imidazolo‐dC Metal‐Mediated Base Pairs: Purine Nucleosides Capture Two Ag+ Ions and Form a Duplex with the Stability of a Covalent DNA Cross‐Link
Authors: Mei Hui , Ingale Sachin A. , Seela Frank
Published: October 2014

8‐Phenylimidazolo‐dC (phImidC, 2) forms metal‐mediated DNA base pairs by entrapping two silver ions. To this end, the fluorescent “purine” 2′‐deoxyribonucleoside 2 has been synthesised and converted into the phosphoramidite 6. Owing to the ease of nucleobase deprotonation, the new Ag+‐mediated base pair containing a “purine” skeleton is much stronger than that derived from the pyrrolo‐ [3,4‐d]pyrimidine system (phPyrdC, 1). The silver‐mediated phImidC–phImidC base pair fits well into the DNA double helix and has the stability of a covalent cross‐link. The formation of such artificial metal base pairs might not be limited to DNA but may be applicable to other nucleic acids such as RNA, PNA and GNA as well as other biopolymers.
Lewis and Brønsted Acid Cocatalyzed Reductive Deoxyallenylation of Propargylic Alcohols with 2‐Nitrobenzenesulfonylhydrazide
Authors: Liu Zhaohong , Liao Peiqiu , Bi Xihe
Published: October 2014

Reductive deoxyallenylation of sterically hindered tertiary propargylic alcohols was realized on reaction with 2‐nitrobenzenesulfonylhydrazide (NBSH) by the combined use of Lewis and Brønsted acid catalysts. This method features a broad substrate scope, mild reaction conditions, and good functional‐group tolerance, and affords various mono‐, di‐, and trisubstituted allenes in good‐to‐excellent yields. The synthetic utility of this method was demonstrated by the synthesis of 2H‐chromenes and 1,2‐dihydroquinolines.
Template‐Free Synthesis of Core–Shell TiO2 Microspheres Covered with High‐Energy {116}‐Facet‐Exposed N‐Doped Nanosheets and Enhanced Photocatalytic Activity under Visible Light
Authors: Chen Qifeng , Ren Baosheng , Zhao Yubao , Xu Xun , Ge Heyi , Guan Ruifang , Zhao Jincai
Published: October 2014

Core–shell TiO2 microspheres possess a unique structure and interesting properties, and therefore, they have received much attention. The high‐energy facets of TiO2 also are being widely studied for the high photocatalytic activities they are associated with. However, the synthesis of the core–shell structure is difficult to achieve and requires multiple‐steps and/or is expensive. Hydrofluoric acid (HF), which is highly corrosive, is usually used in the controlling high‐energy facet production. Therefore, it is still a significant challenge to develop low‐temperature, template‐free, shape‐controlled, and relative green self‐assembly routes for the formation of core–shell‐structured TiO2 microspheres with high‐energy facets. Here, we report a template‐ and hydrofluoric acid free solvothermal self‐assembly approach to synthesize core–shell TiO2 microspheres covered with high‐energy {116}‐facet‐exposed nanosheets, an approach in which 1,4‐butanediamine plays a key role in the formation of nanosheets with exposed {116} facets and the doping of nitrogen in situ. In the structure, nanoparticle aggregates and nanosheets with {116} high‐energy facets exposed act as core and shell, respectively. The photocatalytic activity for degradation of 2,4,6‐tribromophenol and Rhodamine B under visible irradiation and UV/Vis irradiation has been examined, and improved photocatalytic activity under visible light owing to the hierarchical core–shell structure, {116}‐plane‐oriented nanosheets, in situ N doping, and large surface areas has been found.
Inclusion of Two Different Guest Molecules within a Rationally Designed Macrocyclic Boronic Ester in Organic Solvent
Authors: Kikuchi Yuji , Ono Kosuke , Johmoto Kohei , Uekusa Hidehiro , Iwasawa Nobuharu
Published: October 2014

The inclusion of two different guest molecules in a macrocyclic boronic ester in organic solvent utilizing only π‐stacking interactions has been successfully realized. For this purpose, a new tetrol which has an appropriate distance between two 1,2‐diol units for the inclusion of two aromatic molecules is designed and synthesized. Simple mixing of the new tetrol with 2,7‐pyrenediboronic acid in the presence of pyrene‐4,5‐quinone efficiently affords the desired macrocyclic boronic ester, which is found by 1H NMR spectroscopy, ESI‐MS, and isothermal titration calorimetry studies to include one molecule each of a dinitronaphthalimide derivative and pyrene. Furthermore, inclusion of two planar molecules within the macrocyclic boronic ester is revealed by X‐ray analysis.
Unlocking the pH‐Responsive Degradability of Fumaramic Acid Derivatives Using Photoisomerization
Authors: Choi Wonmin , Kang Sunyoung , Mok Yeongbong , Park Euddeum , Song Youngjun , Choi So Jung , Lee Yan
Published: October 2014

Fumaramic acid derivatives can be converted into their cis isomer maleamic acid derivatives under UV illumination, and these maleamic acid derivatives show pH‐responsive degradability at acidic pH only after the preceding photoisomerization. The rate of the tandem photoisomerization–degradation of fumaramic acid derivatives can be finely controlled by changing the substituents on the double bond. Photoisomerization‐based unlocking of the pH‐responsive degradability of fumaramic acid derivatives has strong potential for the development of multisignal‐responsive smart materials in biomedical applications.
System with Potential Dual Modes of Metal–Ligand Cooperation: Highly Catalytically Active Pyridine‐Based PNNH–Ru Pincer Complexes
Authors: Fogler Eran , Garg Jai Anand , Hu Peng , Leitus Gregory , Shimon Linda J. W. , Milstein David
Published: October 2014

Metal–ligand cooperation (MLC) plays an important role in catalysis. Systems reported so far are generally based on a single mode of MLC. We report here a system with potential for MLC by both amine–amide and aromatization–dearomatization ligand transformations, based on a new class of phosphino–pyridyl ruthenium pincer complexes, bearing sec‐amine coordination. These pincer complexes are effective catalysts under unprecedented mild conditions for acceptorless dehydrogenative coupling of alcohols to esters at 35 °C and hydrogenation of esters at room temperature and 5 atm H2. The likely actual catalyst, a novel, crystallographically characterized monoanionic de‐aromatized enamido–RuII complex, was obtained by deprotonation of both the NH and the methylene proton of the N‐arm of the pincer ligand.
Identification of Structural Features of 2‐Alkylidene‐1,3‐Dicarbonyl Derivatives that Induce Inhibition and/or Activation of Histone Acetyltransferases KAT3B/p300 and KAT2B/PCAF
Authors: Castellano Sabrina , Milite Ciro , Feoli Alessandra , Viviano Monica , Mai Antonello , Novellino Ettore , Tosco Alessandra , Sbardella Gianluca
Published: October 2014

Dysregulation of the activity of lysine acetyltransferases (KATs) is related to a variety of diseases and/or pathological cellular states; however, their role remains unclear. Therefore, the development of selective modulators of these enzymes is of paramount importance, because these molecules could be invaluable tools for assessing the importance of KATs in several pathologies. We recently found that diethyl pentadecylidenemalonate (SPV106) possesses a previously unobserved inhibitor/activator activity profile against protein acetyltransferases. Herein, we report that manipulation of the carbonyl functions of a series of analogues of SPV106 yielded different activity profiles against KAT2B and KAT3B (pure KAT2B activator, pan‐inhibitor, or mixed KAT2B activator/KAT3B inhibitor). Among the novel compounds, a few derivatives may be useful chemical tools for studying the mechanism of lysine acetylation and its implications in physiological and/or pathological processes.
Size‐Induced Chiral Discrimination Switching by (S)‐(−)‐2(α‐Hydroxyethyl)Benzimidazole‐Derived Azacrowns
Authors: Pandey Anita D. , Mohammed Hasan , Pissurlenkar Raghuvir R. S. , Karnik Anil V.
Published: October 2014

(S)‐(−)‐2‐(α‐Hydroxyethyl)benzimidazole (1)‐derived diastereomeric monoaza‐[18]crown‐6 compounds 5 and 6 were synthesised with an additional chiral centre bearing a phenyl ring. The aim was to achieve enhanced enantioselective discrimination, compared with monoaza‐[15]crown‐5 (7). Surprisingly, reversal of enantioselective binding for chiral guest enantiomers between the two differently sized [15]crown‐5 and [18]crown‐6 azacrowns were discovered; all three were prepared from the same parent compound, 1. To complete the observations, another [18]crown‐6‐sized azacrown (10) without an additional chiral centre was synthesised from 1 and screened for its enantioselective binding abilities towards the chiral guest enantiomers investigated; these results corroborated the observations. Single‐crystal XRD analysis and molecular docking studies revealed that changes to the conformational aspects of [18]crown‐6 and [15]crown‐5 azacrowns were the major contributing factors to this peculiar behaviour.
Synthesis, Characterisation and Modelling of a Ferromagnetically Coupled Chromium(III) Dimer: Di‐μ‐hydroxobis[tetrakis(isothiocyanato)chromate(III)]
Authors: Morsing Thorbjørn J. , Weihe Høgni , Bendix Jesper
Published: October 2014

A rare example of a ferromagnetically coupled dinuclear chromium(III) complex, the di‐μ‐hydroxobis[tetrakis(isothiocyanato)chromate(III)] anion, is reported. This complex has been synthesised from the oxo‐bridged acetonitrile complex [(CH3CN)5CrOCr(NCCH3)5](BF4)4 and isolated as the solvated tetraphenylphosphonium salt, (Ph4P)4[(SCN)4Cr(OH)2Cr(NCS)4]·2CH3CN (1). From magnetometry the coupling constant, J, was determined to be –5.17 cm–1 (in an H = JSA·SB scheme). The X‐band EPR spectra were measured in the temperature range 2–305 K and the data were modelled. The spectra, which are very rich, are the first reported for a ferromagnetically coupled Cr‐diol, and they allow for detailed modelling that encompasses zero‐field splittings (ZFS) and fourth‐order spin‐Hamiltonian parameters for the coupled system. The structural parameters that determine the magnitude and sign of the exchange coupling were studied with broken‐symmetry DFT. These results are discussed in terms of and compared to existing angular overlap model (AOM)‐based magneto‐structural correlations. This furnishes qualitative as well as quantitative insight into the coupling mechanisms.
Synthesis and Structural Characterization of 2:1 [α/Aza]‐oligomers
Authors: Zhou Zhou , Deng Cheng , Abbas Cécile , Didierjean Claude , Averlant‐Petit Marie‐Christine , Bodiguel Jacques , Vanderesse Régis , Jamart‐Grégoire Brigitte
Published: October 2014

The design of a new β‐turn inducer is correlated to the discovery of new foldamers. In this paper, we report the liquid phase synthesis of 2:1 [α/aza]‐oligomers using a convergent Boc strategy. The NMR, FTIR, restrained molecular dynamics and X‐ray diffraction analyses show that 2:1 [α/aza]‐oligomers adopt a C=O(i)···H–N(i + 2) hydrogen‐bonded helical conformation.
Antibacterial Drug Release Electrochemically Stimulated by the Presence of Bacterial Cells – Theranostic Approach
Authors: Gamella Maria , Guz Nataliia , Mailloux Shay , Pingarrón José M. , Katz Evgeny
Published: October 2014

A modified electrode with bioaffinity to E. coli bacterial cells was used to detect bacteria presence on its surface and to produce an electrical signal triggering antibacterial drug release from another coupled electrode. The Sense‐and‐Treat system was realized in two different versions and suggested as the first step to future theranostic applications where bacteria presence results in automatic antibacterial treatment.
Collapse capacity of soil‐structure systems under pulse‐like earthquakes
Authors: Khoshnoudian Faramarz , Ahmadi Ehsan , Kiani Mahdi , Hadikhan Tehrani Mohammad
Published: October 2014

In this paper, a comprehensive study is carried out to examine the possibility of dynamic instability produced in soil‐structure systems using an ensemble of 50 pulse‐like records. A number of structural models with various vibration periods varying from 0.1 to 2 s are used in this study. The superstructure is simulated as a non‐linear SDOF oscillator with a two‐segment backbone curve having negative post‐yield stiffness. The soil is idealized based on the cone model concept widely used for practical purposes. The results of this investigation demonstrate that as the pulse period increases, the collapse relative lateral strength ratio decreases and probability of dynamic instability enhances. Moreover, soil flexibility makes the system dynamically more unstable, and as the non‐dimensional frequency increases, the collapse relative lateral strength ratio highly reduces. Additionally, the aspect ratio has insignificant effects on the collapse relative lateral strength ratio. Furthermore, comparison of the collapse relative lateral strength ratios resulting from pulse‐like motions with those obtained from studies under non‐pulse‐like motions (Miranda and Akkar; FEMA 440) for fixed‐base conditions shows that high‐velocity pulses exacerbate the dynamic instability problem and decrease the collapse relative lateral strength ratio. Copyright © 2014 John Wiley & Sons, Ltd.
Late‐life depression in Rural China: do village infrastructure and availability of community resources matter?
Authors: Li Lydia W. , Liu Jinyu , Zhang Zhenmei , Xu Hongwei
Published: October 2014

Objectives

This study aimed to examine whether physical infrastructure and availability of three types of community resources (old‐age income support, healthcare facilities, and elder activity centers) in rural villages are associated with depressive symptoms among older adults in rural China.

Method

Data were from the 2011 baseline survey of the Chinese Health and Retirement Longitudinal Study (CHARLS). The sample included 3824 older adults aged 60 years or older residing in 301 rural villages across China. A score of 12 on the 10‐item Center for Epidemiologic Studies Depression Scale was used as the cutoff for depressed versus not depressed. Village infrastructure was indicated by an index summing deficiency in six areas: drinking water, fuel, road, sewage, waste management, and toilet facilities. Three dichotomous variables indicated whether income support, healthcare facility, and elder activity center were available in the village. Respondents' demographic characteristics (age, gender, marital status, and living arrangements), health status (chronic conditions and physical disability), and socioeconomic status (education, support from children, health insurance, household luxury items, and housing quality) were covariates. Multilevel logistic regression was conducted.

Results

Controlling for individuals' socioeconomic status, health status, and demographic characteristics, village infrastructure deficiency was positively associated with the odds of being depressed among rural older Chinese, whereas the provision of income support and healthcare facilities in rural villages was associated with lower odds.

Conclusion

Village infrastructure and availability of community resources matter for depressive symptoms in rural older adults. Improving infrastructure, providing old‐age income support, and establishing healthcare facilities in villages could be effective strategies to prevent late‐life depression in rural China. Copyright © 2014 John Wiley & Sons, Ltd.
Comorbidity as predictor poor prognosis for patients with advanced head and neck cancer treated with major surgery
Authors: Omura Go , Ando Mizuo , Saito Yuki , Kobayashi Kenya , Yamasoba Tatsuya , Asakage Takahiro
Published: October 2014

Background

The impact of comorbidities on patients with advanced head and neck cancer treated with major surgery has not been reported before.

Methods

We retrospectively reviewed clinical charts between 2004 and 2011 at our institution and identified 185 patients with clinical stage III to IV head and neck cancer treated with major surgery. Comorbidities were scored using the Adult Comorbidity Evaluation‐27 (ACE‐27) index manual.

Results

Patients with ACE‐27 ≥2 had significantly worse overall survival (OS) and disease‐specific survival (DSS) than those with ACE‐27 ≤1 (p < .0001 and p = .0047, respectively). Multivariate analyses revealed that ACE‐27 ≥2 and extracapsular spread (ECS) were independently significant adverse prognostic factors for OS and DSS. In addition, patients with ACE‐27 ≥2 had a higher incidence of distant metastases (p = .0057).

Conclusion

The current study suggests that comorbidities may predict poor prognosis and development of distant metastases for patients with advanced head and neck cancer treated with major surgery. © 2015 Wiley Periodicals, Inc. Head Neck 38: 364–369, 2016
Menopausal hormone therapy and central nervous system tumor risk: Large UK prospective study and meta‐analysis
Authors: Benson Victoria S. , Kirichek Oksana , Beral Valerie , Green Jane
Published: October 2014

Female sex hormones are thought to affect women's risk of developing central nervous system (CNS) tumors. Some have reported an increased risk in users of menopausal hormone therapy (HT) but evidence is limited. In the UK General Practice Research Database we compared prospectively collected information on HT prescriptions in women aged 50–79 years with CNS tumors diagnosed in 1987–2011 with that in matched controls (four per case). Relative risks (RRs) in relation to prescribed HT were calculated overall and by CNS tumor subtype. Statistical tests are two‐sided. For all CNS tumors (n = 3,500), glioma (n = 689), meningioma (n = 1,197), acoustic neuroma (n = 439), and pituitary tumors (n = 273) adjusted RRs for women prescribed HT versus not were, respectively, 1.21 (95% confidence intervals (CI) = 1.10–1.32, p < 0.0001), 1.14 (0.93–1.40, p = 0.2), 1.30 (1.11–1.51, p = 0.001), 1.37 (1.06–1.75, p = 0.01), and 1.35 (0.99–1.85, p = 0.06). There was no significant difference in risk by tumor subtype (pheterogeneity = 0.6). A meta‐analysis was conducted, combining our results with those from other published studies with prospectively collected exposure information. The meta‐analyses yielded significantly increased risks for all CNS tumors, glioma and meningioma in users of estrogen‐only [1.35 (1.22–1.49), 1.23 (1.06–1.42) and 1.31 (1.20–1.43), respectively] but not estrogen‐progestin HT [1.09 (0.99–1.19), 0.92 (0.78–1.08) and 1.05 (0.95–1.16), respectively]; these differences were statistically significant (p < 0.005 for each tumor type). There was no significant difference between glioma and meningioma risk in users of estrogen‐only HT. The totality of the available evidence suggests an increased risk of all CNS tumors (and of glioma and meningioma separately) in users of estrogen‐only HT. Absolute excess risk (2 per 10,000 users over 5 years) is small.