bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ocean dynamical processes associated with the tropical Pacific cold tongue mode
Authors: Li Yang , Li Jianping , Zhang Wenjun , Zhao Xia , Xie Fei , Zheng Fei 
Published: August 2015

AbstractThe cold tongue mode (CTM) is the second EOF mode of sea surface temperature anomaly (SSTA) variability over the tropical Pacific and represents the out‐of‐phase relationship in SSTA variability between the Pacific cold tongue region and elsewhere in the tropical Pacific. A positive CTM is characterized by cold SSTA in the Pacific cold tongue region and warm SSTA in the rest of the tropical Pacific, with conditions reversed for a negative CTM. The CTM is a coupled air‐sea mode, and its long‐term variability is most probably induced by ocean dynamical processes in response to global warming [Zhang et al., 2010]. This study focuses on the specific ocean dynamical processes associated with the CTM and its possible relationship with global warming. A heat budget diagnosis of ocean temperature in the eastern equatorial Pacific shows that the net heat flux plays a damping role and the four ocean advection terms (
,
,
, and
) contribute to the temperature change associated with the CTM. Among them, the vertical advection of the anomalous temperature by the mean upwelling (
) makes a dominant contribution to the long‐term change in the CTM. The long‐term change of the term
is controlled mainly by the decreasing vertical gradient of the ocean temperature anomaly (
). The other three advection terms make a minor contribution to the long‐term change in the CTM.
Reassessment and update of long‐term trends in downward surface shortwave radiation over Europe (1939–2012)
Authors: Sanchez‐Lorenzo A. , Wild M. , Brunetti M. , Guijarro J. A. , Hakuba M. Z. , Calbó J. , Mystakidis S. , Bartok B. 
Published: August 2015

AbstractThis paper presents trends in downward surface shortwave radiation (SSR) over Europe, which are based on the 56 longest series available from the Global Energy Balance Archive that are mainly concentrated in central Europe. Special emphasis has been placed on both ensuring the temporal homogeneity and including the most recent years in the data set. We have generated, for the first time, composite time series for Europe covering the period 1939–2012, which have been studied by means of running trend analysis. The mean annual SSR series shows an increase from the late 1930s to the early 1950s (i.e., early brightening), followed by a reduction until mid‐1980s (i.e., global dimming) and a subsequent increase up to the early 2000s (i.e., global brightening). The series ends with a tendency of stabilization since the early 21st century, but the short time period is insufficient with regard to establishing whether a change in the trend is actually emerging over Europe. Seasonal and regional series are also presented, which highlight that similar variations are obtained for most of the seasons and regions across Europe. In fact, due to the strong spatial correlation in the SSR series, few series are enough to capture almost the same interannual and decadal variability as using a dense network of stations. Decadal variations of the SSR are expected to have an impact on the modulation of the temperatures and other processes over Europe linked with changes in the hydrological cycle, agriculture production, or natural ecosystems. For a better dissemination of the time series developed in this study, the data set is freely available for scientific purposes.
Sources and atmospheric processes impacting oxalate at a suburban coastal site in Hong Kong: Insights inferred from 1 year hourly measurements
Authors: Zhou Yang , Huang Xiaohui Hilda , Bian Qijing , Griffith Stephen M. , Louie Peter K. K. , Yu Jian Zhen 
Published: August 2015

AbstractOxalic acid is one of the most abundant dicarboxylic acids in the atmosphere, receiving a great deal of attention due to its potential influence on cloud condensation nucleus activities. In this work, we report 10 months of hourly oxalate measurements in particulate matter of less than 2.5 µm in aerodynamic diameter (PM2.5) by a Monitor for Aerosols and Gases in ambient Air at a suburban coastal site in Hong Kong from April 2012 to February 2013. A total of more than 6000 sets of oxalate and inorganic ion data were obtained. The mean (±SD) oxalate concentration was 0.34 (±0.18) µg m−3, accounting for 2.8% of the total ion mass and 1.5% of the PM2.5 mass. Seasonal variation showed higher concentrations in fall and winter (0.54 and 0.36 µg m−3, respectively) and lower concentrations in spring and summer (~0.26 µg m−3). Different from the inorganic ions, a shallow dip in the oxalate concentration consistently occurred in the morning after sunrise (around 9:00 A.M.) throughout all seasons. Our analysis suggests that this was likely due to photolysis of oxalate‐Fe (III) complex under sunlight. In summer, a small daytime peak was discernable for oxalate and nitrate. This characteristic, together with a more evident diurnal variation of O3, indicates comparatively more active photochemical oxidation in summer than other seasons. High correlations were observed between oxalate and non‐sea‐salt SO42− (NSS) (R2 = 0.63) and Ox (O3 + NO2) (R2 = 0.48), indicating significant commonality in their secondary formation. Positive matrix factorization analysis of oxalate and other real‐time gas and particle‐phase component data estimates that secondary formation processes, including secondary gas or aqueous oxidation processes (49%), oxidation processes of biomass burning emissions (37%), accounted for the majority of PM2.5 oxalate. A backward trajectories cluster analysis found that higher oxalate/NSS ratios were associated with low pollution samples under the influence of marine air masses while the ratios were lower in high pollution samples that were typically associated with continental air masses passing through areas of high anthropogenic emissions. Isolating the “low pollution marine” aerosols across the entire data set indicates that oxalate production increased in the summer compared to other seasons, suggesting either more active marine emissions of oxalate precursors or stronger photochemical processes in the summer.
Fault‐tolerant control using command‐filtered adaptive back‐stepping technique: Application to hypersonic longitudinal flight dynamics
Authors: Xu Bin , Guo Yuyan , Yuan Yuan , Fan Yonghua , Wang Danwei 
Published: August 2015

SummaryIn this paper, the adaptive back‐stepping controller is investigated for a class of strict‐feedback systems using the command filter technique. Adaptive laws are designed for updating the controller parameters when both the plant parameters and actuator‐failure parameters are unknown. Furthermore, the auxiliary dynamics is developed to deal with the input constraints. Closed‐loop stability and asymptotic‐state tracking are ensured. The method is applied to the longitudinal dynamics of a generic hypersonic aircraft in the presence of actuator faults and input constraints. Based on the parameter estimation, the command‐filtered adaptive back‐stepping control is presented. Simulation results on the control‐oriented model show that the proposed approach achieves good tracking performance. Copyright © 2015 John Wiley & Sons, Ltd.
Optimal expansions of multivariable ARX processes on Laguerre bases via the Newton–Raphson method
Authors: El Anes Amani , Maraoui Saber , Bouzrara Kais 
Published: August 2015

SummaryIn this article, an optimal linear MIMO system approximation by using discrete‐time MIMO autoregressive with exogenous input (ARX) model is proposed. Each polynomial function of the MIMO ARX model associated with the inputs and with the outputs is expanded on independent Laguerre orthonormal basis. The resulting model is entitled MIMO ARX–Laguerre model. The optimal approximation of which is ensured once the poles characterizing each Laguerre orthonormal basis are set to their optimal values. In this paper, a new method to estimate, from input/output measurements, the optimal Laguerre poles of the MIMO ARX–Laguerre model is proposed. The method consists in applying the Newton–Raphson's iterative technique in which the gradient and the Hessian are expressed analytically. The proposed algorithm is tested on a numerical example and on a benchmark system. Simulation results show the effectiveness of the proposed optimal modeling method. Copyright © 2015 John Wiley & Sons, Ltd.
Enantioselective Addition of Heteroarylboronates to Arylimines Catalyzed by a Rhodium‐Diene Complex
Authors: Chen Ya‐Jing , Cui Zhe , Feng Chen‐Guo , Lin Guo‐Qiang 
Published: August 2015

AbstractAn enantioselective rhodium‐catalyzed 1,2‐addition of heteroarylboronates to aryl N‐tosylimines and N‐nosylimines has been developed. Our chiral rhodium‐diene catalyst showed high efficiency in the stereochemical control of this reaction. Under the optimal reaction conditions, a variety of boronates bearing pyridinyl, furyl or thienyl groups were successfully reacted with aryl imines. The boronate type, with balance of the stability and reactivity, is critical for achieving high reaction yields in this reaction.magnified image
The association between weekly work hours, crew familiarity, and occupational injury and illness in emergency medical services workers
Authors: Weaver Matthew D. , Patterson P. Daniel , Fabio Anthony , Moore Charity G. , Freiberg Matthew S. , Songer Thomas J. 
Published: August 2015

ObjectiveEmergency Medical Services (EMS) workers are shift workers in a high‐risk, uncontrolled occupational environment. EMS‐worker fatigue has been associated with self‐reported injury, but the influence of extended weekly work hours is unknown.MethodsA retrospective cohort study was designed using historical shift schedules and occupational injury and illness reports. Using multilevel models, we examined the association between weekly work hours, crew familiarity, and injury or illness.ResultsIn total, 966,082 shifts and 950 reports across 14 EMS agencies were obtained over a 1–3 year period. Weekly work hours were not associated with occupational injury or illness. Schedule characteristics that yield decreased exposure to occupational hazards, such as part‐time work and night work, conferred reduced risk of injury or illness.ConclusionsExtended weekly work hours were not associated with occupational injury or illness. Future work should focus on transient exposures and agency‐level characteristics that may contribute to adverse work events. Am. J. Ind. Med. 58:1270–1277, 2015. © 2015 Wiley Periodicals, Inc.
Styrene‐associated health outcomes at a windblade manufacturing plant
Authors: McCague Anna‐Binney , Cox‐Ganser Jean M. , Harney Joshua M. , Alwis K. Udeni , Blount Benjamin C. , Cummings Kristin J. , Edwards Nicole , Kreiss Kathleen 
Published: August 2015

BackgroundHealth risks of using styrene to manufacture windblades for the green energy sector are unknown.MethodsUsing data collected from 355 (73%) current windblade workers and regression analysis, we investigated associations between health outcomes and styrene exposure estimates derived from urinary styrene metabolites.ResultsThe median current styrene exposure was 53.6 mg/g creatinine (interquartile range: 19.5–94.4). Color blindness in men and women (standardized morbidity ratios 2.3 and 16.6, respectively) was not associated with exposure estimates, but was the type previously reported with styrene. Visual contrast sensitivity decreased and chest tightness increased (odds ratio 2.9) with increasing current exposure. Decreases in spirometric parameters and FeNO, and increases in the odds of wheeze and asthma‐like symptoms (odds ratios 1.3 and 1.2, respectively) occurred with increasing cumulative exposure.ConclusionsDespite styrene exposures below the recommended 400 mg/g creatinine, visual and respiratory effects indicate the need for additional preventative measures in this industry. Am. J. Ind. Med. 58:1150–1159, 2015. © 2015 Wiley Periodicals, Inc.
The Expanded Genetic Alphabet
Authors: Malyshev Denis A. , Romesberg Floyd E. 
Published: August 2015

AbstractAll biological information, since the last common ancestor of all life on Earth, has been encoded by a genetic alphabet consisting of only four nucleotides that form two base pairs. Long‐standing efforts to develop two synthetic nucleotides that form a third, unnatural base pair (UBP) have recently yielded three promising candidates, one based on alternative hydrogen bonding, and two based on hydrophobic and packing forces. All three of these UBPs are replicated and transcribed with remarkable efficiency and fidelity, and the latter two thus demonstrate that hydrogen bonding is not unique in its ability to underlie the storage and retrieval of genetic information. This Review highlights these recent developments as well as the applications enabled by the UBPs, including the expansion of the evolution process to include new functionality and the creation of semi‐synthetic life that stores increased information.
Practical Electrochemical Anodic Oxidation of Polycyclic Lactams for Late Stage Functionalization
Authors: Frankowski Kevin J. , Liu Ruzhang , Milligan Gregory L. , Moeller Kevin D. , Aubé Jeffrey 
Published: August 2015

AbstractElectrochemistry provides a powerful tool for the late‐stage functionalization of complex lactams. A two‐stage protocol for converting lactams, many of which can be prepared through the intramolecular Schmidt reaction of keto azides, is presented. In the first step, anodic oxidation in MeOH using a repurposed power source provides a convenient route to lactams bearing a methoxy group adjacent to nitrogen. Treatment of these intermediates with a Lewis acid in dichloromethane permits the regeneration of a reactive acyliminium ion that is then reacted with a range of nucleophilic species.
Structure, Biosynthesis, and Occurrence of Bacterial Pyrrolizidine Alkaloids
Authors: Schimming Olivia , Challinor Victoria L. , Tobias Nicholas J. , Adihou Hélène , Grün Peter , Pöschel Laura , Richter Christian , Schwalbe Harald , Bode Helge B. 
Published: August 2015

AbstractPyrrolizidine alkaloids (PAs) are widespread plant natural products with potent toxicity and bioactivity. Herein, the identification of bacterial PAs from entomopathogenic bacteria using differential analysis by 2D NMR spectroscopy (DANS) and mass spectrometry is described. Their biosynthesis was elucidated to involve a non‐ribosomal peptide synthetase. The occurrence of these biosynthesis gene clusters in Gram‐negative and Gram‐positive bacteria indicates an important biological function in bacteria.
Synthesis of Bridged Diketopiperazines by Using the Persistent Radical Effect and a Formal Synthesis of Bicyclomycin
Authors: Amatov Tynchtyk , Pohl Radek , Císařová Ivana , Jahn Ullrich 
Published: August 2015

AbstractA conceptually new and unified approach to diverse bridged diketopiperazines (DKPs) with widely variable ring sizes was developed by taking advantage of the persistent radical effect. This method enables synthesis of the core structures of bridged DKP alkaloids and was applied to a formal synthesis of the antibiotic bicyclomycin.
Porphyrin Boxes: Rationally Designed Porous Organic Cages
Authors: Hong Soonsang , Rohman Md. Rumum , Jia Jiangtao , Kim Youngkook , Moon Dohyun , Kim Yonghwi , Ko Young Ho , Lee Eunsung , Kim Kimoon 
Published: August 2015

AbstractThe porphyrin boxes (PB‐1 and PB‐2), which are rationally designed porous organic cages with a large cavity using well‐defined and rigid 3‐connected triangular and 4‐connected square shaped building units are reported. PB‐1 has a cavity as large as 1.95 nm in diameter and shows high chemical stability in a broad pH range (4.8 to 13) in aqueous media. The crystalline nature as well as cavity structure of the shape‐persistent organic cage crystals were intact even after complete removal of guest molecules, leading to one of the highest surface areas (1370 m2g−1) among the known porous organic molecular solids. The size of the cavities and windows of the porous organic cages can be modulated using different sized building units while maintaining the topology of the cages, as illustrated with PB‐2. Interestingly, PB‐2 crystals showed unusual N2 sorption isotherms as well as high selectivity for CO2 over N2 and CH4 (201 and 47.9, respectively at 273 K at 1 bar).
Optogenetic Apoptosis: Light‐Triggered Cell Death
Authors: Hughes Robert M. , Freeman David J. , Lamb Kelsey N. , Pollet Rebecca M. , Smith Weston J. , Lawrence David S. 
Published: August 2015

AbstractAn optogenetic Bax has been designed that facilitates light‐induced apoptosis. We demonstrate that mitochondrial recruitment of a genetically encoded light‐responsive Bax results in the release of mitochondrial proteins, downstream caspase‐3 cleavage, changes in cellular morphology, and ultimately cell death. Mutagenesis of a key phosphorylatable residue or modification of the C‐terminus mitigates background (dark) levels of apoptosis that result from Bax overexpression. The mechanism of optogenetic Bax‐mediated apoptosis was explored using a series of small molecules known to interfere with various steps in programmed cell death. Optogenetic Bax appears to form a mitochondrial apoptosis‐induced channel analogous to that of endogenous Bax.
Parental risk factors for oral clefts among Central Africans, Southeast Asians, and Central Americans
Authors: Figueiredo Jane C. , Ly Stephanie , Magee Kathleen S. , Ihenacho Ugonna , Baurley James W. , Sanchez‐Lara Pedro A. , Brindopke Frederick , Nguyen Thi‐Hai‐Duc , Nguyen Viet , Tangco Maria Irene , Giron Melissa , Abrahams Tamlin , Jang Grace , Vu Annie , Zolfaghari Emily , Yao Caroline A. , Foong Athena , DeClerk Yves A. , Samet Jonathan M. , Magee William 
Published: August 2015

BackgroundSeveral lifestyle and environmental exposures have been suspected as risk factors for oral clefts, although few have been convincingly demonstrated. Studies across global diverse populations could offer additional insight given varying types and levels of exposures.MethodsWe performed an international case–control study in the Democratic Republic of the Congo (133 cases, 301 controls), Vietnam (75 cases, 158 controls), the Philippines (102 cases, 152 controls), and Honduras (120 cases, 143 controls). Mothers were recruited from hospitals and their exposures were collected from interviewer‐administered questionnaires. We used logistic regression modeling to estimate odds ratios (OR) and 95% confidence intervals (CI).ResultsFamily history of clefts was strongly associated with increased risk (maternal: OR = 4.7; 95% CI, 3.0–7.2; paternal: OR = 10.5; 95% CI, 5.9–18.8; siblings: OR = 5.3; 95% CI, 1.4–19.9). Advanced maternal age (5 year OR = 1.2; 95% CI, 1.0–1.3), pregestational hypertension (OR = 2.6; 95% CI, 1.3–5.1), and gestational seizures (OR = 2.9; 95% CI, 1.1–7.4) were statistically significant risk factors. Lower maternal (secondary school OR = 1.6; 95% CI, 1.2–2.2; primary school OR = 2.4, 95% CI, 1.6–2.8) and paternal education (OR = 1.9; 95% CI, 1.4–2.5; and OR = 1.8; 95% CI, 1.1–2.9, respectively) and paternal tobacco smoking (OR = 1.5, 95% CI, 1.1–1.9) were associated with an increased risk. No other significant associations between maternal and paternal factors were found; some environmental factors including rural residency, indoor cooking with wood, chemicals and water source appeared to be associated with an increased risk in adjusted models.ConclusionOur study represents one of the first international studies investigating risk factors for clefts among multiethnic underserved populations. Our findings suggest a multifactorial etiology including both maternal and paternal factors. Birth Defects Research (Part A) 103:863–879, 2015. © 2015 The Authors Birth Defects Research Part A: Clinical and Molecular Teratology Published by Wiley Periodicals, Inc.
Facile Synthesis of Highly Efficient p–n Heterojunction CuO/BiFeO3 Composite Photocatalysts with Enhanced Visible‐Light Photocatalytic Activity
Authors: Niu Feng , Chen Da , Qin Laishun , Zhang Ning , Wang Jiangying , Chen Zhi , Huang Yuexiang 
Published: August 2015

AbstractA novel heterostructured CuO/BiFeO3 composite photocatalyst was successfully prepared through a simple combination of hydrothermal and impregnation process. CuO was uniformly deposited on the surface of BiFeO3 particles with a p–n heterojunction formed at the interface between CuO and BiFeO3. CuO/BiFeO3 heterostructured photocatalysts improved the UV/Vis spectral absorption ability, and exhibited enhanced photocatalytic activities for photodegradation of methylorange or a colorless compound (i.e., phenol) under visible light. In addition, after five recycles for the photodegradation of methylorange, CuO/BiFeO3 did not exhibit significant loss of photocatalytic activity, confirming its stability and long‐time reusability. The enhanced photocatalytic activity could be mainly ascribed to the p–n heterojunction structure between CuO and BiFeO3, which could significantly facilitate the separation and transfer of photogenerated electron–hole pairs. On the basis of the calculated energy bands, the photocatalytic mechanism was also proposed.
A Self‐Reporting Tetrazole‐Based Linker for the Biofunctionalization of Gold Nanorods
Authors: Stolzer Lukas , Vigovskaya Antonina , Barner‐Kowollik Christopher , Fruk Ljiljana 
Published: August 2015

AbstractA photochemical approach based on nitrile imine‐mediated tetrazole‐ene cycloaddition is introduced to functionalize gold nanorods with biomolecules. For this purpose, a bifunctional, photoreactive linker containing thioctic acid as the Au anchoring group and a tetrazole moiety for the light‐induced reaction with maleimide‐capped DNA was prepared. The tetrazole‐based reaction on the nanoparticles’ surface results in a fluorescent pyrazoline product allowing for the spectroscopic monitoring of the reaction. This first example of nitrile imine‐mediated tetrazole‐ene cycloaddition (NITEC)‐mediated biofunctionalization of Au nanorods paves the way for the attachment of sensitive biomolecules, such as antibodies and other proteins, under mild conditions and expands the toolbox for the tailoring of nanomaterials.
Base‐Promoted Coupling of Carbon Dioxide, Amines, and Diaryliodonium Salts: A Phosgene‐ and Metal‐Free Route to O‐Aryl Carbamates
Authors: Xiong Wenfang , Qi Chaorong , Peng Youbin , Guo Tianzuo , Zhang Min , Jiang Huanfeng 
Published: August 2015

AbstractA phosgene‐ and metal‐free synthesis of O‐aryl carbamates is realized through a three‐component coupling of carbon dioxide, amines and diaryliodonium salts. The reaction only requires a base as the promoter, providing access to a diverse array of O‐aryl carbamates in moderate to high yields with excellent chemoselectivity.
Efficient Automated Solid‐Phase Synthesis of DNA and RNA 5′‐Triphosphates
Authors: Sarac Ivo , Meier Chris 
Published: August 2015

AbstractA fast, high‐yielding and reliable method for the synthesis of DNA‐ and RNA 5′‐triphosphates is reported. After synthesizing DNA or RNA oligonucleotides by automated oligonucleotide synthesis, 5‐chloro‐saligenyl‐N,N‐diisopropylphosphoramidite was coupled to the 5′‐end. Oxidation of the formed 5′‐phosphite using the same oxidizing reagent used in standard oligonucleotide synthesis led to 5′‐cycloSal‐oligonucleotides. Reaction of the support‐bonded 5′‐cycloSal‐oligonucleotide with pyrophosphate yielded the corresponding 5′‐triphosphates. The 5′‐triphosphorylated DNA and RNA oligonucleotides were obtained after cleavage from the support in high purity and excellent yields. The whole reaction sequence was adapted to be used on a standard oligonucleotide synthesizer.