bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of the oceanic bridge in linking the 18.6 year modulation of tidal mixing and long‐term SST change in the North Pacific
Authors: Osafune S. , Masuda S. , Sugiura N. 
Published: October 2014

AbstractThe impact of the 18.6 year modulation of tidal mixing on sea surface temperature (SST) in the North Pacific is investigated in a comparative study using an ocean data synthesis system. We show that remote impact through a slow ocean response can make a significant contribution to the observed bidecadal variation in wintertime SST near the center of action of the Pacific Decadal Oscillation in the eastern Pacific. A comparative data synthesis experiment showed that the modified SST variation is amplified by bidecadal variation in the westerly wind. This relationship between SST and wind variations is consistent with an observed air‐sea coupled mode in the extratropics, which suggests that a midlatitude air‐sea interaction plays an important role in enhancing the climate signal of the 18.6 year modulation. This result supports the hypothesis that the 18.6 year tidal cycle influences long‐term variability in climate; thus, knowledge of this cycle could contribute toward improving decadal predictions of climate.
An improved satellite‐based approach for estimating vapor pressure deficit from MODIS data
Authors: Zhang Hongmei , Wu Bingfang , Yan Nana , Zhu Weiwei , Feng Xueliang 
Published: October 2014

AbstractVapor pressure deficit (VPD) is an important variable widely used in ecosystem and climate models. In this paper, an improved satellite‐based approach to estimating VPD was presented that uses several remote sensing products coupled with field measured data. The proposed method exploits an optimized algorithm to derive near‐surface actual vapor pressure (ea) from Moderate Resolution Imaging Spectroradiometer (MODIS) data and upgrades Smith's (1966) methodology for estimating ea. The proposed new algorithm for calculating ea was evaluated against in situ measurements at 119 validation sites in China for 2 months in 2013. The mean absolute error (MAE) and root‐mean‐square error (RMSE) were less than 0.25 kPa and 0.33 kPa, respectively. The near‐surface air temperature (Ta), which is an important input data for calculating VPD, was estimated from satellite‐retrieved land surface temperature, and had an RMSE of less than 2.5 K. The estimated VPD values were validated with ground observation data from the Heihe River Basin for 5 months in 2012 and for all of China for August 2013. A coefficient of determination (R2) of 0.912, MAE of 0.27 kPa, and RMSE value of 0.32 kPa were achieved for the 2012 test data, and corresponding values of 0.88, 0.278 kPa, and 0.367 kPa for the 2013 test data. These results are promising, especially considering the comparatively high spatial resolution (1 km) of the VPD map estimated from the satellite data. Potential applications include global evapotranspiration estimation, fire warning, and vegetation analysis.
Difference in particle formation at a mountaintop location during spring and summer: Implications for the role of sulfuric acid and organics in nucleation
Authors: Yu Fangqun , Hallar A. Gannet 
Published: October 2014

AbstractNew particle formation (NPF) has been observed frequently at Storm Peak Laboratory (SPL), a high‐elevation mountaintop observatory in Colorado. A detailed analysis of field measurements taken in March and July 2012 at SPL reveals significant and interesting differences in NPF during the spring and summer months. Persistent long‐lasting NPF occurred on a daily basis in March but was absent in July. Bursts of ultrafine particles did occur frequently in July, but such bursts were short‐lasting and did not show any obvious pattern. A global chemical transport model (GEOS‐Chem) coupled with a size‐resolved advanced particle microphysics model is used to interpret in‐depth this observed nucleation phenomenon. The model captures well the observed persistent daily nucleation events in March and the absence of regional‐scale NPF in July. Model simulations indicate that aerosol precursors were dominated by H2SO4 gas in March and by low‐volatile secondary organic gases (LV‐SOGs) in July, which are consistent with previous particle composition measurements at SPL. The observed persistent daily NPF in March and the absence of regional‐scale nucleation in July at SPL indicate that H2SO4 gas plays a much more critical role in the initial nucleation process, although LV‐SOGs dominate particle growth in July. Our analysis suggests that the short‐lasting bursts of ultrafine particles observed at SPL in July are likely associated with nucleation in subgrid power plant plumes, where concentrations of H2SO4 rather than LV‐SOGs are expected to be higher.
Random Evolutions
Authors: Koroliuk V.S. , Limnios N. 
Published: October 2014

AbstractThis article gives a short presentation of random evolutions. First, the following two examples are presented: dynamical stochastic systems and increment processes, both in Markov media. Then, an introduction to semi‐Markov Random evolution in a Banach space is given, where the previous evolutionary systems are obtained as particular cases. Finally, two abstract limit theorems of average and diffusion approximation for continuous and jump semi‐Markov random evolutions are presented. Remarks on bibliography and further topics related to random evolutions are given.
Preparation of Stereoregular Isotactic Poly(mandelic acid) through Organocatalytic Ring‐Opening Polymerization of a Cyclic O‐Carboxyanhydride
Authors: Buchard Antoine , Carbery David R. , Davidson Matthew G. , Ivanova Petya K. , Jeffery Ben J. , Kociok‐Köhn Gabriele I. , Lowe John P. 
Published: October 2014

AbstractPoly(mandelic acid) (PMA) is an aryl analogue of poly(lactic acid) (PLA) and a biodegradable analogue of polystyrene. The preparation of stereoregular PMA was realized using a pyridine/mandelic acid adduct (Py⋅MA) as an organocatalyst for the ring‐opening polymerization (ROP) of the cyclic O‐carboxyanhydride (manOCA). Polymers with a narrow polydispersity index and excellent molecular‐weight control were prepared at ambient temperature. These highly isotactic chiral polymers exhibit an enhancement of the glass‐transition temperature (Tg) of 15 °C compared to the racemic polymer, suggesting potential future application as high‐performance commodity and biomedical materials.
Dilithium Hexaorganostannate(IV) Compounds
Authors: Schrader Ireen , Zeckert Kornelia , Zahn Stefan 
Published: October 2014

AbstractHypercoordination of main‐group elements such as the heavier Group 14 elements (silicon, germanium, tin, and lead) usually requires strong electron‐withdrawing ligands and/or donating groups. Herein, we present the synthesis and characterization of two hexaaryltin(IV) dianions in form of their dilithium salts [Li2(thf)2{Sn(2‐pyMe)6}] (pyMe=C5H3N‐5‐Me) (2) and [Li2{Sn(2‐pyOtBu)6}] (pyOtBu=C5H3N‐6‐OtBu) (3). Both complexes are stable in the solid state and solution under inert conditions. Theoretical investigations of compound 2 reveal a significant valence 5s‐orbital contribution of the tin atom forming six strongly polarized tin–carbon bonds.
Asymmetric Triple Relay Catalysis: Enantioselective Synthesis of Spirocyclic Indolines through a One‐Pot Process Featuring an Asymmetric 6π Electrocyclization
Authors: Yin Xiao‐Ping , Zeng Xing‐Ping , Liu Yun‐Lin , Liao Fu‐Min , Yu Jin‐Sheng , Zhou Feng , Zhou Jian 
Published: October 2014

AbstractA rare example of a one‐pot process that involves asymmetric triple relay catalysis is reported. The key step is an asymmetric [1,5] electrocyclic reaction of functionalized ketimines. The substrates for this process were obtained in situ in a two‐step process that involved the hydrogenation of nitroarenes with a Pd/C catalyst to yield aryl amines and their subsequent coupling with isatin derivatives in a Brønsted acid catalyzed ketimine formation reaction. The electrocyclization was catalyzed by a bifunctional chiral Brønsted base/hydrogen bond donor catalyst. The one‐pot process gave the desired products in good yields and with excellent enantioselectivity.
A Simple and Highly Effective Ligand System for the Copper(I)‐Mediated Assembly of Rotaxanes
Authors: Campbell Christopher J. , Leigh David A. , Vitorica‐Yrezabal Inigo J. , Woltering Steffen L. 
Published: October 2014

AbstractA [2]rotaxane was produced through the assembly of a picolinaldehyde, an amine, and a bipyridine macrocycle around a CuItemplate by imine bond formation in close‐to‐quantitative yield. An analogous [3]rotaxane is obtained in excellent yield by replacing the amine with a diamine, thus showing the suitability of the system for the construction of higher order interlocked structures. The rotaxanes are formed within a few minutes simply through mixing the components in solution at room temperature and they can be isolated through removal of the solvent or precipitation.
Nasal Morphometry in Marmosets: Loss and Redistribution of Olfactory Surface Area
Authors: Smith Timothy D. , Eiting Thomas P. , Bonar Christopher J. , Craven Brent A. 
Published: October 2014

ABSTRACTThe two major groups of primates differ in internal nasal anatomy. Strepsirrhines (e.g., lemurs) have more numerous turbinals and recesses compared with haplorhines (e.g., monkeys). Since detailed quantitative comparisons of nasal surface area (SA) have not been made, we measured mucosa in serially sectioned monkeys (Callithrix jacchus, Cebuella pygmaea). Data were compared with previously published findings on the mouse lemur, Microcebus murinus. The nasal airways were digitally reconstructed using computed tomography scanned heads of Cebuella and Microcebus. In addition, morphometric and functional analyses were carried out using segmented photographs of the histological sections of Cebuella and Microcebus. The SA of the ethmoturbinal complex is about half as large in marmosets compared with Microcebus, and is covered with less olfactory mucosa (18%–24% in marmosets, compared with ∼50% in Microcebus). Whereas the ethmoturbinal complex of Microcebus bears half of the total olfactory mucosa in the nasal airway, most (∼80%) olfactory mucosa is distributed on other surfaces in the marmosets (e.g., nasal septum). A comparison to previously published data suggests all primate species have less olfactory surface area (OSA) compared with other similar‐sized mammals, but this is especially true of marmosets. Taken together, these findings support the hypothesis that there is a reduced OSA in at least some haplorhines, and this can be linked to diminished posterosuperior dimensions of the nasal fossae. However, haplorhines may have minimized their olfactory loss by redistributing olfactory mucosa on non‐turbinal surfaces. Our findings also imply that airflow patterns in the olfactory region differ among primates. Anat Rec, 297:2093–2104, 2014. © 2014 Wiley Periodicals, Inc.
Review of the Cetacean Nose: Form, Function, and Evolution
Authors: Berta Annalisa , Ekdale Eric G. , Cranford Ted W. 
Published: October 2014

ABSTRACTThe cetacean nose presents a unique suite of anatomical modifications. Key among these is posterior movement of the external nares from the tip of the rostrum to the top of the head. Concomitant with these anatomical changes are functional changes including the evolution of echolocation in odontocetes, and reduction of olfaction in Neoceti (crown odontocetes and mysticetes). Anatomical and embryological development of the nose in crown cetaceans is reviewed as well as their functional implications. A sequence of evolutionary transformations of the nose is proposed in the transition from a terrestrial to an aquatic lifestyle made by whales. Basilosaurids and all later whales reduce the nasal turbinates. The next stage characterizes Neoceti which exhibit reduction of the major olfactory structures, i.e. the ethmoturbinates, cribriform plate and maxilloturbinates with further reduction and subsequent loss in odontocetes. These anatomical modifications reflect underlying genetic changes such as the reduction of olfactory receptor genes, although mysticetes retain some olfactory abilities. Modifications of the facial and nasal region of odontocetes reflect specialization for biosonar sound production. Anat Rec, 297:2205–2215, 2014. © 2014 Wiley Periodicals, Inc.
Nitro‐Substituted Bishomocubanes: Synthesis, Characterization, and Application as Energetic Materials
Authors: Lal Sohan , Rajkumar Sundaram , Tare Amit , Reshmi Sasidharakurup , Chowdhury Arindrajit , Namboothiri Irishi N. N. 
Published: October 2014

AbstractSeveral high‐energy‐density strained polycyclic compounds nitromethyl‐l,3‐bishomocubane (NMBHC), nitromethylene‐1,3‐bishomocubane (NMyBHC), and bis(nitromethyl)‐1,3‐bishomocubane (DNTMBHC), which were synthesized for the first time from bishomocubanone, hold potential for application as standalone fuels in liquid bipropellant systems or as additives in liquid and solid propellant formulations. DFT analysis at the B3LYP/6‐31G(d) level of theory was employed to optimize the geometries of the compounds and to determine their densities, heats of formation, and various thermodynamic properties. The density specific impulse, determined by using equilibrium thermodynamics, demonstrated an improvement of 75 s for NMBHC and NMyBHC over standard hydrocarbons. The specific impulse with ammonium perchlorate showed an improvement of 25–30 s over hydroxy‐terminated polybutadiene. Thermogravimetric analysis revealed that NMBHC, NMyBHC, and DNTMBHC evaporated readily with activation energies of 58.8, 69.2, and 74.5 kJ mol−1, respectively.
Formation Tracking Control of Multi‐Vehicle Systems
Authors: Dong Runsha , Geng Zhiyong 
Published: October 2014

AbstractIn this paper, the problem of trajectory tracking of multiple vehicles in a manner of rigid formation is studied. Each vehicle is modeled as a rigid body whose dynamics evolve on Euclidean groups and by which, both position and attitude of the vehicle are considered. The formation control problem of multiple vehicles is decomposed into decentralised control problems of pairs of a vehicle and its parent vehicle. A distributed control law is proposed for vehicles to track a predefined trajectory with desired formations. A numerical simulation is finally included to verify the theoretical results.
Genetic variation in GABRA2 moderates peer influence on externalizing behavior in adolescents
Authors: Villafuerte Sandra , Trucco Elisa M. , Heitzeg Mary M. , Burmeister Margit , Zucker Robert A. 
Published: October 2014

AbstractBackgroundGenetic predisposition and environmental influences are both important factors in the development of problematic behavior leading to substance use in adolescence. Involvement with delinquent peers also strongly predicts adolescent externalizing behavior. Several lines of evidence support a role of GABRA2 on externalizing behavior related to disinhibition. However, whether this genetic association is influenced by the environment such as peer behavior remains unknown.MethodsWe examined the moderating role of GABRA2 genetic variation on the socialization model of delinquent peer affiliation (at ages 12–14 years) on externalizing behavior (at ages 15–17 years) in the Michigan Longitudinal Study (MLS) adolescent sample.The sample consisted of 244 adolescents (75 females and 152 with at least one parent with a DSM‐IV lifetime alcohol dependence/abuse diagnosis). Peer delinquent activity reported by the participant and teacher‐reported adolescent externalizing behavior (Teacher Report Form (TRF) were assessed.ResultsNo main effect of the GABRA2 SNP rs279826, which tags a large haplotype, on externalizing behavior was observed. However, there was a statistically reliable GABRA2 × peer delinquency interaction. The effect of peer delinquent involvement on externalizing scores and the rule breaking subscale is significantly stronger for those with the GG genotype compared to A‐carriers, whereas there was no effect of genotype on externalizing in the absence of peer delinquent involvement. No interaction was observed for the aggression subscale.ConclusionOur results suggest that the genetic effect of GABRA2 on externalizing behavior, more specifically on rule breaking is, at least in part, due to its effect on susceptibility to environmental exposure (i.e., peer delinquency).
Electrochemical Characterisation of Nanoscale Liquid|Liquid Interfaces Located at Focused Ion Beam‐Milled Silicon Nitride Membranes
Authors: Sairi Masniza , Chen‐Tan Nigel , Neusser Gregor , Kranz Christine , Arrigan Damien W. M. 
Published: October 2014

AbstractThe electrochemical behaviour of single and arrayed nanoscale interfaces between two immiscible electrolyte solutions (single and array nanoITIES) is presented. The interfaces were formed at nanopores fabricated through the focused ion beam (FIB) milling of silicon nitride (SiN) membranes by using nanopores with approximately 30–80 nm radii and with pore‐to‐pore separations to pore radius ratios in the range of 16–32. Electrochemistry was performed through the interfacial transfer of tetrapropylammonium (TPrA+) across single and array nanoITIES between water and 1,6‐dichlorohexane. The ion‐transfer limiting current at the single nanoITIES was in excellent agreement with the current predicted by using an inlaid disc interface model. At nanoITIES arrays, experimental currents were lower than predicted for an array of inlaid interfaces, which is attributed to overlapped diffusion zones. As a result, FIB milling offers an attractive strategy to form nanoITIES for diverse investigations.
Rationally Designed Axially Chiral Diarylethene Switches with High Helical Twisting Power
Authors: Li Yannian , Wang Mengfei , Wang Hao , Urbas Augustine , Li Quan 
Published: October 2014

AbstractThree rationally designed axially chiral diarylethene switches were synthesized and their application as chiral dopants for phototunable cholesteric liquid crystal devices was investigated. Design of these molecules was based on the combination of photochromic dithienylcyclopentene core with bridged binaphthyl units as chiral precursors. Aromatic groups were introduced to the molecules at 6,6′‐positions of binaphthyls through a Suzuki–Miyaura coupling reaction. Their helical twisting powers (HTPs) are significantly higher than those of the known chiral diarylethenes reported as chiral dopants so far. Photocyclization of these molecules upon light irradiation brought out dramatic variation in HTPs between different states. The primary colors, red, green, and blue, were obtained in reflection on light irradiation and with thermal stability. Moreover, a multi‐switchable photodisplay was demonstrated using one of these chiral molecular switches.
A Stereoselective Switch: Enantiodivergent Approach to the Synthesis of Isoflavanones
Authors: Doran Robert , Carroll Michael P. , Akula Ramulu , Hogan Bryan F. , Martins Marta , Fanning Séamus , Guiry Patrick J. 
Published: October 2014

AbstractA modular six‐step asymmetric synthesis of two naturally occurring and three non‐natural isoflavanones containing tertiary α‐aryl carbonyls is reported. This synthetic route, utilising a Pd‐catalyzed decarboxylative asymmetric protonation, produces isoflavanones in excellent enantioselectivities from 76–97 %. A switch in the sense of stereoinduction was observed when different H+ sources were employed, showing the first example of dual stereocontrol in an asymmetric protonation reaction. The first enantioselective synthesis of the naturally occurring isoflavanones sativanone and 3‐o‐methylviolanone has been accomplished.
Enantioselective Degradation of Metalaxyl in Grape, Tomato, and Rice Plants
Authors: Wang Meiyun , Hua Xiude , Zhang Qing , Yang Yu , Shi Haiyan , Wang Minghua 
Published: October 2014

AbsractEnantioselective biodegradation of chiral pesticide metalaxyl in grape, tomato, and rice plants under field conditions were studied. Metalaxyl enantiomers were completely separated with a resolution (Rs) of 5.01 by high‐performance liquid chromatography (HPLC) based on a cellulose tris (3‐chloro‐4‐methyl phenyl carbamate) chiral column (Lux Cellulose‐2). Metalaxyl enantiomers from matrixes were extracted by acetonitrile and purged using Cleanert Alumina‐A solid phase extraction (SPE). The linearity, recovery, precision, sensitivity, and matrix effect of the method were assessed. The result showed that significant stereoselectivity occurred in grape, tomato, and rice plants. In grape, (+)‐S‐metalaxyl with a half‐life of 5.5 d degraded faster than (–)‐R‐metalaxyl with that of 6.9 d, and the enantiomer fraction (EF) value reached 0.37 at 21 d. The same enantioselectivity was observed in tomato, and the half‐life was 2.2 d for the S‐enantiomer and 3.0 d for the R‐enantiomer. The EF values decreased from 0.49 of 0 d to 0.26 of 14 d. On the other hand, a preferential degradation of the R‐form was found in rice plants, with an EF value of 0.70 at 14 d, and the corresponding half‐life was 2.3 d for the R‐form and 2.8 d for the S‐form. Chirality 27:109–114, 2015. © 2014 Wiley Periodicals, Inc.
Comparison of different kinetic models for the chlorohydrin process using real data from an industrial tubular reactor
Authors: Petric Ivan , Husanović Amel 
Published: October 2014

AbstractThe main objective of this study was to investigate how different kinetic models for the chlorohydrin process can influence the simulation results. In order to accomplish this objective, a simplified reactor model was developed and applied on the kinetic models. The simulation results were compared with actual process data (three different data sets) from an industrial tubular reactor in order to find the most appropriate kinetic model as well as to validate the model. The results of numerical simulations showed good agreement with the measured actual values. The influences of the reactor length, the input flow temperature and the entering molar flows of components on the process performance were studied using the validated mathematical model. The maximum molar flow rate of propylene oxide was achieved with temperature of the entering reaction mixture of 57 °C. The reactor length, the input flow temperature and the molar flows of components have the strongest influence on overall selectivity of propylene oxide related to propylene glycol.
Drug Delivery to the Malaria Parasite Using an Arterolane‐Like Scaffold
Authors: Fontaine Shaun D. , Spangler Benjamin , Gut Jiri , Lauterwasser Erica M. W. , Rosenthal Philip J. , Renslo Adam R. 
Published: October 2014

AbstractAntimalarial agents artemisinin and arterolane act via initial reduction of a peroxide bond in a process likely mediated by ferrous iron sources in the parasite. Here, we report the synthesis and antiplasmodial activity of arterolane‐like 1,2,4‐trioxolanes specifically designed to release a tethered drug species within the malaria parasite. Compared with our earlier drug delivery scaffolds, these new arterolane‐inspired systems are of significantly decreased molecular weight and possess superior metabolic stability. We describe an efficient, concise and scalable synthesis of the new systems, and demonstrate the use of the aminonucleoside antibiotic puromycin as a chemo/biomarker to validate successful drug release in live Plasmodium falciparum parasites. Together, the improved drug‐like properties, more efficient synthesis, and proof of concept using puromycin, suggests these new molecules as improved vehicles for targeted drug delivery to the malaria parasite.