bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar rotation effects on the Martian ionosphere
Authors: Venkateswara Rao N. , Balan N. , Patra A. K.
Published: July 2014

We present a detailed investigation of the solar rotation effects on the Martian high‐latitude (~63°N–81°N) ionosphere using the electron density (Ne) data measured by Mars Global Surveyor and solar XUV and EUV fluxes measured by SOHO under high (2000–2001), medium (2003), and low (2005) solar activity conditions. A fast Fourier transform spectral analysis method is used to estimate the amplitude of the rotation period in these parameters. This method clearly reveals the presence of solar rotation effects in the Martian ionospheric Ne at all altitudes (90–220 km), peak electron density (NmM2), and total electron content under the three solar activity conditions. These effects are in phase with the solar UV fluxes (corrected for the Martian orbit). The period of rotation effect (~26 days) is the same at all altitudes, though its amplitude is strongest at the ionospheric M2 peak (~135–140 km, ~3.5–6% of the mean values) and has a secondary enhancement at the M1 peak (~110–115 km). The effect of solar rotation on the M2 peak is larger during medium solar activity (2003) than during high solar activity (2000–2001). The effect, however, is absent in the ionospheric peak height (hmM2). The rotation effects on Mars are also compared with those on the Earth. Unlike at Mars, the Earth's high‐latitude ionosphere shows no clear solar rotation effect, though the effect is observed clearly at lower latitudes.
Suprathermal magnetospheric minor ions heavier than water at Saturn: Discovery of 28M+ seasonal variations
Authors: Christon S. P. , Hamilton D. C. , Mitchell D. G. , DiFabio R. D. , Krimigis S. M.
Published: July 2014

Water group ions W+ (O+, OH+, H2O+, and H3O+), along with H+ and H2+, dominate Saturn's near‐equatorial magnetospheric suprathermal ion populations. The singly charged, minor heavy ions O2+ and 28M+ were also observed in the suprathermal energy range, but at much lower densities, having ≤10−2 the abundance of W+. From 2004 through 2013, Cassini's charge‐energy‐mass ion spectrometer has measured suprathermal 83–167 keV/e heavy ions at ~4–20 Rs (1 Saturn radius, Rs = 60,268 km). Christon et al. (2013) found apparent O2+/W+ transient and seasonal responses to variable insolation of Saturn's ring atmosphere prior to mid‐2012. A similar seasonal variation in 28M+/W+ (28M+ ~27–30 amu/e molecular minor ions) was suggested but inconclusive. Now with data from mid‐2012 through 2013, we find that both O2+ and 28M+ clearly exhibit seasonal recoveries from mid‐2012 onward. Prominent radial partial number density peaks at ~9 Rs identify W+, O2+, and 28M+ as clear ring current participants. It is presently unclear which part of Saturn's magnetosphere produces the seasonally varying 28M+ component. Dissimilar 28M+/W+ and O2+/W+ responses to a strong late 2011 solar UV burst suggest different seasonal ring‐based photolytic processes.
Ion cyclotron waves at Mars: Occurrence and wave properties
Authors: Wei H. Y. , Cowee M. M. , Russell C. T. , Leinweber H. K.
Published: July 2014

Ion cyclotron waves (ICWs) are generated during the interaction between the solar wind and the Martian exosphere in a process called ion pickup. Mars Global Surveyor (MGS) detected waves near the proton gyrofrequency, indicating pickup of the exospheric hydrogen. To analyze these waves, we first improve the zero levels of the MGS magnetic field data taken during the first aerobreaking phase and then perform a statistical study of the ICWs observed from just outside the Martian bow shock to over 14 Mars radii away. These ICW events typically last for 5 to 30 min but can occasionally last for hours. The wave power decreases slowly with distance on both the upstream and downstream sides. From the variation of wave properties with the strength of the background field, we find that there are likely still remaining offsets in at least some the data sets even after applying our calibration technique. Thus, we use the events with a strong background field to examine the wave properties that depend on an accurate determination of the field direction and strength. We find the pickup angle associated with the largest occurrence rate of ICWs to be around 45°, but neither the wave amplitude, nor wave frequency, nor wave duration appear to vary with pickup angle. Finally, we find the waves with background field strength greater than 4 nT occur on both the positive and negative electric field sides of Mars but have a larger occurrence rate on the side of Mars in the positive electric field direction (which is defined as the direction of the cross product of the magnetic field vector and solar wind flow vector).
SAR observation and numerical modeling of tidal current wakes at the East China Sea offshore wind farm
Authors: Li XiaoMing , Chi Lequan , Chen Xueen , Ren YongZheng , Lehner Susanne
Published: July 2014

A TerraSAR‐X (TS‐X) Synthetic Aperture Radar (SAR) image acquired at the East China Sea offshore wind farm presents distinct wakes at a kilometer scale on the lee of the wind turbines. The presumption was that these wakes were caused by wind movement around turbine blades. However, wind analysis using spaceborne radiometer data, numerical weather prediction, and in situ measurements suggest that the prevailing wind direction did not align with the wakes. By analyzing measurement at the tidal gauge station and modeling of the tidal current field, these trailing wakes are interpreted to have formed when a strong tidal current impinged on the cylindrical monopiles of the wind turbines. A numerical simulation was further conducted to reproduce the tidal current wake under such conditions. Comparison of the simulated surface velocity in the wake region with the TS‐X sea surface backscatter intensity shows a similar trend. Consequently, turbulence intensity (T.I.) of the tidal current wakes over multiple piles is studied using the TS‐X observation. It is found that the T.I. has a logarithmic relation with distance. Furthermore, another case study showing wakes due to wind movement around turbine blades is presented to discuss the differences in the tidal current wakes and wind turbine wakes. The conclusion is drawn that small‐scale wakes formed by interaction of the tidal current and the turbine piles could be also imaged by SAR when certain conditions are satisfied. The study is anticipated to draw more attentions to the impacts of offshore wind foundations on local hydrodynamic field.
Estimating satellite salinity errors for assimilation of Aquarius and SMOS data into climate models
Authors: Vinogradova Nadya T. , Ponte Rui M. , Fukumori Ichiro , Wang Ou
Published: July 2014

Constraining dynamical systems with new information from ocean measurements, including observations of sea surface salinity (SSS) from Aquarius and SMOS, requires careful consideration of data errors that are used to determine the importance of constraints in the optimization. Here such errors are derived by comparing satellite SSS observations from Aquarius and SMOS with ocean model output and in situ data. The associated data error variance maps have a complex spatial pattern, ranging from less than 0.05 in the open ocean to 1–2 (units of salinity variance) along the coasts and high latitude regions. Comparing the data‐model misfits to the data errors indicates that the Aquarius and SMOS constraints could potentially affect estimated SSS values in several ocean regions, including most tropical latitudes. In reference to the Aquarius error budget, derived errors are less than the total allocation errors for the Aquarius mission accuracy requirements in low and midlatitudes, but exceed allocation errors in high latitudes.
Impact of an extreme flood event on optical and biogeochemical properties in a subtropical coastal periurban embayment (Eastern Australia)
Authors: Oubelkheir Kadija , Ford Phillip W. , Clementson Lesley A. , Cherukuru Nagur , Fry Gary , Steven Andrew D. L.
Published: July 2014

Major floods impacted the city of Brisbane, eastern Australia, in January 2011, delivering large amounts of dissolved and particulate materials and nutrients into the adjacent coastal embayment, Moreton Bay. The resulting spatially resolved changes in biogeochemical and optical properties in Moreton Bay were examined 1, 2, 6, 19, and 49 weeks after the main freshwater discharge. One week postflood, total suspended matter (TSM) and chlorophyll a (TChla) concentrations varied over 1 order of magnitude throughout Moreton Bay, the particle scattering coefficient at 555 nm varied by a factor of 20, and the total absorption coefficient and colored dissolved organic matter (CDOM) absorption coefficient at 440 nm varied by a factor of 5. The largest changes in biogeochemical and optical properties observed during our study were from 1 to 2 weeks after the floods: near the Brisbane River mouth, TSM decreased by a factor of 3, CDOM by a factor of 2, while TChla increased by a factor of 3. Within a year, optical and biogeochemical properties recovered to levels similar to nonflood conditions. The strong changes in the characteristics of the particulate and dissolved material following the flood event and subsequent biological and photochemical processes led to a large spatial and temporal variability in the relative contribution of different constituents to the total absorption coefficient at 440 nm, the particle single scattering albedo, and the specific inherent optical properties. This work has significant implications for the accuracy of standard ocean color remote sensing algorithms in coastal waters during flood events.
Influences of soil moisture and vegetation on convective precipitation forecasts over the United States Great Plains
Authors: Collow Thomas W. , Robock Alan , Wu Wei
Published: July 2014

This study investigates the influences of soil moisture and vegetation on 30 h convective precipitation forecasts using the Weather Research and Forecasting model over the United States Great Plains with explicit treatment of convection. North American Regional Reanalysis (NARR) data were used as initial and boundary conditions. We also used an adjusted soil moisture (uniformly adding 0.10 m3/m3 over all soil layers based on NARR biases) to determine whether using a simple observationally based adjustment of soil moisture forcing would provide more accurate simulations and how the soil moisture addition would impact meteorological parameters for different vegetation types. Current and extreme (forest and barren) land covers were examined. Compared to the current vegetation cover, the complete removal of vegetation produced substantially less precipitation, while conversion to forest led to small differences in precipitation. Adding 0.10 m3/m3 to the soil moisture with the current vegetation cover lowered the near surface temperature and increased the humidity to a similar degree as using a fully forested domain with no soil moisture adjustment. However, these temperature and humidity effects on convective available potential energy and moist enthalpy nearly canceled each other out, resulting in a limited precipitation response. Although no substantial changes in precipitation forecasts were found using the adjusted soil moisture, the similarity found between temperature and humidity forecasts using the increased soil moisture and those with a forested domain highlights the sensitivity of the model to soil moisture changes, reinforcing the need for accurate soil moisture initialization in numerical weather forecasting models.
Geomagnetic storms, super‐storms, and their impacts on GPS‐based navigation systems
Authors: Astafyeva E. , Yasyukevich Yu. , Maksikov A. , Zhivetiev I.
Published: July 2014

Using data of GPS receivers located worldwide, we analyze the quality of GPS performance during four geomagnetic storms of different intensity: two super‐storms and two intense storms. We show that during super‐storms the density of GPS Losses‐of‐Lock (LoL) increases up to 0.25% at L1 frequency and up to 3% at L2 frequency, and up to 0.15% (at L1) and 1% (at L2) during less intense storms. Also, depending on the intensity of the storm time ionospheric disturbances, the total number of total electron content (TEC) slips can exceed from 4 to 40 times the quiet time level. Both GPS LoL and TEC slips occur during abrupt changes of SYM‐H index of geomagnetic activity, i.e., during the main phase of geomagnetic storms and during development of ionospheric storms. The main contribution in the total number of GPS LoL was found to be done by GPS sites located at low and high latitudes, whereas the area of numerous TEC slips seemed to mostly correspond to the boundary of the auroral oval, i.e., region with intensive ionospheric irregularities. Our global maps of TEC slips show where the regions with intense irregularities of electron density occur during geomagnetic storms and will let us in future predict appearance of GPS errors for geomagnetically disturbed conditions.
Fabrication of Nanoparticle‐Containing Films and Nano Layers for Alloying and Joining
Authors: Leifert Annika , Mondin Giovanni , Dörfler Susanne , Hampel Silke , Kaskel Stefan , Hofmann Evelyn , Zschetzsche Jörg , Pflug Erik , Dietrich Georg , Rühl Maximilian , Braun Stefan , Schädlich Stefan
Published: July 2014

Nanoparticles (NPs) can improve mechanical properties of construction elements. However, the integration is not trivial due to the nanoscopic nature of the particles and the different material properties of particle and device: new processing routes have to be found for homogeneous incorporation. Therefore, a wet chemical synthesis is established to incorporate various ceramic NPs such as TiO2, TiC, SiC, and WC in copper films in desired concentrations. Depending on the kind and concentration of NPs, hardness and wear resistance of copper are enhanced. The resulting metal matrix composite films are thus of high interest for various applications such as reinforced electrical contacts and in aerospace and automotive technology. The energy released in an exothermic reaction of a reactive multilayer system (RMS) can be used as a precise and well‐defined local heat source for joining the surface of polymers. In this case, a RMS consisting of alternating layers of nickel and aluminum is used. The design of the RMS is adjusted in a way that despite the intensive but very short reaction no damaging of the polymers occurs. The joining process takes only milliseconds and does not require any pre‐ or post‐treatment of the polymers. With the optimal joining parameters, e.g., the joining load, for fiber non‐reinforced polymers tensile strengths can be achieved, which lead to a material failure by tensile attempts. Preliminary tests of fiber reinforced polymers result in a tensile strength that is characteristic for adhesive polymer bonding. Model simulations show that only the first few micrometers of the materials surface are in a liquid state for a very short period of time. In addition to the applied joining load, the materials composition and specifically the resulting solidification process of the liquid polymer phase result in a strong bond between polymer samples that have to be joined. Materials with different thermal expansion coefficients are difficult to join thermally. Among them is the joining of solar cells. It is conventionally carried out by heating the whole assembly. Due to the thermal differences between tabbing wire and silicon, deformations as well as changes in the microstructure can occur. In the worst case, damage of the whole assembly is possible. Upon inspection of the joining process, the high energy consumption of the process itself is also critical.
Epitaxial Growth of PbSe Quantum Dots on MoS2 Nanosheets and their Near‐Infrared Photoresponse
Authors: Schornbaum Julia , Winter Benjamin , Schießl Stefan P. , Gannott Florentina , Katsukis Georgios , Guldi Dirk M. , Spiecker Erdmann , Zaumseil Jana
Published: July 2014

A facile one‐pot synthesis of hybrid materials consisting of PbSe quantum dots (QDs) that grow epitaxially on MoS2 nanoflakes resulting in three equivalent orientation variants of the PbSe QDs with respect to the MoS2 lattice is demonstrated. The epitaxial growth and cross‐sectional high‐resolution transmission electron microscopy (HRTEM) investigations verify a direct and linker‐free contact between the quantum dots and the transition metal dichalcogenide (TMD) nanoflakes, while maintaining surface passivation of the PbSe with oleic acid ligands on the outside. Solution‐processed photodetectors based on PbSe‐MoS2 hybrids exhibit stable photoconduction when illuminated with near‐IR light (wavelength > 1200 nm) without any laborious ligand‐exchange steps. Flexible devices fabricated on polyethylene terephthalate (PET) substrates show excellent stability upon repeated bending. These hybrid materials are air‐stable and solution‐processable at low temperatures and thus promising for low‐cost flexible near‐IR photodetectors.
Remarkably Improved Electrode Performance of Bulk MnS by Forming a Solid Solution with FeS – Understanding the Li Storage Mechanism
Authors: Zhao Liang , Yu Xiqian , Yu Juezhi , Zhou Yongning , Ehrlich Steven. N. , Hu Yong‐Sheng , Su Dong , Li Hong , Yang Xiao‐Qing , Chen Liquan
Published: July 2014

Transition metal compounds based on conversion reactions are promising electrode materials for lithium‐ion batteries due to their higher lithium storage capacity compared with currently available commercial battery electrodes. Most of the studies on these materials in the literature focus on transition metal oxides and fluorides, and not much work on transition metal sulphides has been reported, partially due to their relatively poor electrochemical performance. Here, synthesis and characterization of a series of solid solution FexMn1‐xS (x = 0.2, 0.5, 0.8) monosulphide compounds is reported. Interestingly, hexagonal FeS and cubic MnS can form a solid solution of FexMn1‐xS (x < 0.57). It is demonstrated that the lithium storage voltage can be tuned by changing the Fe concentration in the FexMn1‐xS matrix; meanwhile, the discharge‐charge coulombic efficiency and cycle stability of FexMn1‐xS are greatly enhanced in comparison with that of pure MnS. A half cell using Fe0.5Mn0.5S as electrode material achieves a high first cycle coulombic efficiency of 78.0% and a high reversible capacity of ca. 477 mAh g−1 after 35 cycles, while for pure MnS the first cycle coulombic efficiency is only 45.9% and the capacity rapidly fades to ≈200 mAh g−1 after 15 cycles. Although the solid solution state of Fe0.5Mn0.5S cannot be retained during conversion reaction as indicated by X‐ray diffraction (XRD), X‐ray absorption spectroscopy (XAS), and transmission electron microscopy (TEM), the initial discharge “polarization”, which has been considered as one of the major hurdles for conversion reaction, can be significantly reduced by this type of material design. In addition, the size and distribution of the nucleated nanophases might also be altered by the initial solid solution state of Fe0.5Mn0.5S, contributing to the improved electrochemical performance reported here.
Reduced Mesoporous Co3O4 Nanowires as Efficient Water Oxidation Electrocatalysts and Supercapacitor Electrodes
Authors: Wang Yongcheng , Zhou Tong , Jiang Kun , Da Peimei , Peng Zheng , Tang Jing , Kong Biao , Cai Wen‐Bin , Yang Zhongqin , Zheng Gengfeng
Published: July 2014

While electrochemical water splitting is one of the most promising methods to store light/electrical energy in chemical bonds, a key challenge remains in the realization of an efficient oxygen evolution reaction catalyst with large surface area, good electrical conductivity, high catalytic properties, and low fabrication cost. Here, a facile solution reduction method is demonstrated for mesoporous Co3O4 nanowires treated with NaBH4. The high‐surface‐area mesopore feature leads to efficient surface reduction in solution at room temperature, which allows for retention of the nanowire morphology and 1D charge transport behavior, while at the same time substantially increasing the oxygen vacancies on the nanowire surface. Compared to pristine Co3O4 nanowires, the reduced Co3O4 nanowires exhibit a much larger current of 13.1 mA cm‐2 at 1.65 V vs reversible hydrogen electrode (RHE) and a much lower onset potential of 1.52 V vs RHE. Electrochemical supercapacitors based on the reduced Co3O4 nanowires also show a much improved capacitance of 978 F g‐1 and reduced charge transfer resistance. Density‐functional theory calculations reveal that the existence of oxygen vacancies leads to the formation of new gap states in which the electrons previously associated with the Co‐O bonds tend to be delocalized, resulting in the much higher electrical conductivity and electrocatalytic activity.
Framework for correlating the effect of temperature on nonelectrolyte and ionic liquid activity coefficients
Authors: Frank Timothy C. , Arturo Steven G. , Holden Bruce S.
Published: July 2014

A power‐law expression is proposed for correlating the temperature dependence of infinite‐dilution activity coefficients (
) for nonelectrolyte solute–solvent binary pairs and for pairs including an ionic liquid:
, where θij = 0 for Lewis–Randall ideal solutions, θij = 1 for classic enthalpy‐based Scatchard–Hildebrand regular solution and van Laar models, and −5 < θij < 5 for most real binaries. The exponent θij is a function of partial molar excess enthalpy (
) and entropy (
) such that
. Real binaries are classified into seven types corresponding to distinct domains of
and θij. The new method provides a framework for correlating phase‐equilibrium driven temperature effects for a wide variety of chemical and environmental applications. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3675–3690, 2014
Enhancement of flux and solvent stability of Matrimid® thin‐film composite membranes for organic solvent nanofiltration
Authors: Sun Shi‐Peng , Chung Tai‐Shung , Lu Kang‐Jia , Chan Sui‐Yung
Published: July 2014

The development of high flux and solvent‐stable thin‐film composite (TFC) organic solvent nanofiltration (OSN) membranes was reported. A novel cross‐linked polyimide substrate, consisting of a thin skin layer with minimum solvent transport resistance and a sponge‐like sublayer structure that could withstand membrane compaction under high‐pressure was first fabricated. Then the solvent flux was significantly enhanced without compromising the solute rejection by the coupling effects of (1) the addition of triethylamine/camphorsulfonic acid into the monomer solution, and (2) the combined post‐treatments of glycerol/sodium dodecyl sulphate immersion and dimethyl sulfoxide (DMSO) filtration. Finally, the long‐term stability of the TFC membrane in aprotic solvents such as DMSO was improved by post‐crosslink thermal annealing. The novel TFC OSN membrane developed was found to have superior rejection to tetracycline (MW: 444 g/mol) but was very permeable to alcohols such as methanol (5.12 lm−2h−1bar−1) and aprotic solvents such as dimethylformamide (3.92 lm−2h−1bar−1) and DMSO (3.34 lm−2h−1bar−1). © 2014 American Institute of Chemical Engineers AIChE J, 60: 3623–3633, 2014
Silent cerebral infarction, income, and grade retention among students with sickle cell anemia
Authors: King Allison A. , Rodeghier Mark J. , Panepinto Julie Ann , Strouse John J. , Casella James F. , Quinn Charles T. , Dowling Michael M. , Sarnaik Sharada A. , Thompson Alexis A. , Woods Gerald M. , Minniti Caterina P. , Redding‐Lallinger Rupa C. , Kirby‐Allen Melanie , Kirkham Fenella J. , McKinstry Robert , Noetzel Michael J. , White Desiree A. , Kwiatkowski Janet K. , Howard Thomas H. , Kalinyak Karen A. , Inusa Baba , Rhodes Melissa M. , Heiny Mark E. , Fuh Ben , Fixler Jason M. , Gordon Mae O. , DeBaun Michael R.
Published: July 2014

Children with sickle cell anemia have a higher‐than‐expected prevalence of poor educational attainment. We test two key hypotheses about educational attainment among students with sickle cell anemia, as measured by grade retention and use of special education services: (1) lower household per capita income is associated with lower educational attainment; (2) the presence of a silent cerebral infarct is associated with lower educational attainment. We conducted a multicenter, cross‐sectional study of cases from 22 U.S. sites included in the Silent Infarct Transfusion Trial. During screening, parents completed a questionnaire that included sociodemographic information and details of their child's academic status. Of 835 students, 670 were evaluable; 536 had data on all covariates and were used for analysis. The students' mean age was 9.4 years (range: 5–15) with 52.2% male; 17.5% of students were retained one grade level and 18.3% received special education services. A multiple variable logistic regression model identified that lower household per capita income (odds ratio [OR] of quartile 1 = 6.36, OR of quartile 2 = 4.7, OR of quartile 3 = 3.87; P = 0.001 for linear trend), age (OR = 1.3; P < 0.001), and male gender (OR, 2.2; P = 0.001) were associated with grade retention; silent cerebral infarct (P = 0.31) and painful episodes (P = 0.60) were not. Among students with sickle cell anemia, household per capita income is associated with grade retention, whereas the presence of a silent cerebral infarct is not. Future educational interventions will need to address both the medical and socioeconomic issues that affect students with sickle cell anemia. Am. J. Hematol. 89:E188–E192, 2014. © 2014 Wiley Periodicals, Inc.
An unexpected prolonged coma due to a pharmacobezoar formed from Vegetamine A® tablet ingestion
Authors: Sato Chie , Kamijo Yoshito
Published: July 2014

Case

A 49‐year‐old man ingested massive quantities of Vegetamine A® tablets that contain two anticholinergic agents in addition to phenobarbital. The patient remained in an unexpectedly prolonged coma 4 days post‐hospitalization. An acute gastroscopy revealed a pinkish‐white pharmacobezoar on the lesser curvature of the stomach, which was extracted using a net. Direct hemoperfusion and treatment with multiple‐dose activated charcoal was then initiated. Phenobarbital serum concentrations eventually decreased, resulting in complete recovery of the patient.

Outcome

On day 30, the patient was transferred to the Psychiatric Department.

Conclusion

An intragastric pharmacobezoar should be suspected in patients with promoted and prolonged toxicity or if high serum concentrations of agents indicate their continuous absorption.
Genetic and phenotypic diversity of NHE6 mutations in Christianson syndrome
Authors: Pescosolido Matthew F. , Stein David M. , Schmidt Michael , El Achkar Christelle Moufawad , Sabbagh Mark , Rogg Jeffrey M. , Tantravahi Umadevi , McLean Rebecca L. , Liu Judy S. , Poduri Annapurna , Morrow Eric M.
Published: July 2014

Objective

Recently, Christianson syndrome (CS) has been determined to be caused by mutations in the X‐linked Na+/H+ exchanger 6 (NHE6). We aimed to determine the diagnostic criteria and mutational spectrum for CS.

Methods

Twelve independent pedigrees (14 boys, age = 4–19 years) with mutations in NHE6 were administered standardized research assessments, and mutations were characterized.

Results

The mutational spectrum was composed of 9 single nucleotide variants, 2 indels, and 1 copy number variation deletion. All mutations were protein‐truncating or splicing mutations. We identified 2 recurrent mutations (c.1498 c>t, p.R500X; and c.1710 g>a, p.W570X). Otherwise, all mutations were unique. In our study, 7 of 12 mutations (58%) were de novo, in contrast to prior literature wherein mutations were largely inherited. We also report prominent neurological, medical, and behavioral symptoms. All CS participants were nonverbal and had intellectual disability, epilepsy, and ataxia. Many had prior diagnoses of autism and/or Angelman syndrome. Other neurologic symptoms included eye movement abnormalities (79%), postnatal microcephaly (92%), and magnetic resonance imaging evidence of cerebellar atrophy (33%). Regression was noted in 50%, with recurrent presentations involving loss of words and/or the ability to walk. Medical symptoms, particularly gastrointestinal symptoms, were common. Height and body mass index measures were below normal ranges in most participants. Behavioral symptoms included hyperkinetic behavior (100%), and a majority exhibited high pain threshold.

Interpretation

This is the largest cohort of independent CS pedigrees reported. We propose diagnostic criteria for CS. CS represents a novel neurogenetic disorder with general relevance to autism, intellectual disability, Angelman syndrome, epilepsy, and regression. Ann Neurol 2014;76:581–593
Catalytic Enantioselective Carboannulation with Allylsilanes
Authors: Ball‐Jones Nicolas R. , Badillo Joseph J. , Tran Ngon T. , Franz Annaliese K.
Published: July 2014

The first catalytic asymmetric carboannulation with allylsilanes is presented. The enantioselective [3+2] annulation is catalyzed using a scandium(III)/indapybox complex with tetrakis‐[3,5‐bis(trifluoromethyl)phenyl]‐borate (BArF) to enhance catalytic activity and control stereoselectivity. Functionalized cyclopentanes containing a quaternary carbon center are derived from alkylidene oxindole, coumarin, and malonate substrates with high stereoselectivity. The enantioselective 1,4‐conjugate addition and enantioselective lactone formation (by trapping of the β‐silyl carbocation) is also described.
CNH2 Bond Formation Mediated by Iridium Complexes
Authors: Mena Inmaculada , Casado Miguel A. , Polo Víctor , García‐Orduña Pilar , Lahoz Fernando J. , Oro Luis A.
Published: July 2014

In the presence of phosphanes (PR3), the amido‐bridged trinuclear complex [{Ir(μ‐NH2)(tfbb)}3] (tfbb=tetrafluorobenzobarrelene) transforms into mononuclear discrete compounds [Ir(1,2‐η2‐4‐κ‐C12H8F4N)(PR3)3], which are the products of the CN coupling between the amido moiety and a vinylic carbon of the diolefin. An alternative synthetic approach to these species involves the reaction of the 18 e− complex [Ir(Cl)(tfbb)(PMePh2)2] with gaseous ammonia and additional phosphane. DFT studies show that both transformations occur through nucleophilic attack. In the first case the amido moiety attacks a diolefin coordinated to a neighboring molecule following a bimolecular mechanism induced by the highly basic NH2 moiety; the second pathway involves a direct nucleophilic attack of ammonia to a coordinated tfbb molecule.
Evidence of Dihydrogen Bonding of a Chiral Amine–Borane Complex in Solution by VCD Spectroscopy
Authors: Merten Christian , Berger Christopher J. , McDonald Robert , Xu Yunjie
Published: July 2014

IR and vibrational circular dichroism (VCD) spectra of a chiral amine–borane in solution are investigated. By comparison of experimental and calculated spectra, unique VCD spectral signatures, which can be attributed to the formation of dihydrogen‐bonded dimers in solution, are identified for the first time. These VCD features are highly sensitive to the specific dihydrogen‐bonding topologies utilized by the chiral amine–borane subunits and thus provide direct structural information of these dihydrogen‐bonded species in solution. Differences in the dihydrogen binding arrangements in solution and in solid state are also revealed.
High Correlation between Oxidation Loci on Graphene Oxide
Authors: Yang Jinrong , Shi Guosheng , Tu Yusong , Fang Haiping
Published: July 2014

Recent experiments have shown the coexistence of both large unoxidized and oxidized regions on graphene oxide (GO), but the underlying mechanism for the formation of the GO atomic structure remains unknown. Now, using density functional calculations, 52 oxidation pathways for local pyrene structures on GO were identified, and a kinetic profile for graphene oxidation with a high correlation between oxidation loci was proposed, which is different from the conventional view, which entails a random distribution of oxidation loci. The high correlation is an essential nature of graphene oxidation processes and can be attributed to three crucial effects: 1) breaking of delocalized π bonds, 2) steric hindrance, and 3) hydrogen‐bond formation. This high correlation leads to the coexistence of both large unoxidized and oxidized regions on GO. Interestingly, even in oxidized regions on GO, some small areas of sp2‐hybridized domains, similar to “islands”, can persist because of steric effects.
In Situ Quantification and Visualization of Lithium Transport with Neutrons
Authors: Liu Danny X. , Wang Jinghui , Pan Ke , Qiu Jie , Canova Marcello , Cao Lei R. , Co Anne C.
Published: July 2014

A real‐time quantification of Li transport using a nondestructive neutron method to measure the Li distribution upon charge and discharge in a Li‐ion cell is reported. By using in situ neutron depth profiling (NDP), we probed the onset of lithiation in a high‐capacity Sn anode and visualized the enrichment of Li atoms on the surface followed by their propagation into the bulk. The delithiation process shows the removal of Li near the surface, which leads to a decreased coulombic efficiency, likely because of trapped Li within the intermetallic material. The developed in situ NDP provides exceptional sensitivity in the temporal and spatial measurement of Li transport within the battery material. This diagnostic tool opens up possibilities to understand rates of Li transport and their distribution to guide materials development for efficient storage mechanisms. Our observations provide important mechanistic insights for the design of advanced battery materials.
Advancing the Drug Discovery and Development Process
Authors: Nicolaou K. C.
Published: July 2014

The current state of affairs in the drug discovery and development process is briefly summarized and then ways to take advantage of the ever‐increasing fundamental knowledge and technical knowhow in chemistry and biology and related disciplines are discussed. The primary motivation of this Essay is to celebrate the great achievements of chemistry, biology, and medicine and to inform and inspire students and academics to enter the field of drug discovery and development while, at the same time, continue to advance the fundamentals of their disciplines. It is also meant to encourage and catalyze multidisciplinary partnerships between academia and industry as scientists attempt to merge their often complementary interests and expertise to achieve new improvements and breakthroughs in their respective fields, and the common goal of applying them to the discovery and invention of new and better medicines, especially in areas of unmet needs.
A Polyphenylene Support for Pd Catalysts with Exceptional Catalytic Activity
Authors: Wang Feng , Mielby Jerrik , Richter Felix Herrmann , Wang Guanghui , Prieto Gonzalo , Kasama Takeshi , Weidenthaler Claudia , Bongard Hans‐Josef , Kegnæs Søren , Fürstner Alois , Schüth Ferdi
Published: July 2014

We describe a solid polyphenylene support that serves as an excellent platform for metal‐catalyzed reactions that are normally carried out under homogeneous conditions. The catalyst is synthesized by palladium‐catalyzed Suzuki coupling which directly results in formation of palladium nanoparticles confined to a porous polyphenylene network. The composite solid is in turn highly active for further Suzuki coupling reactions, including non‐activated substrates that are challenging even for molecular catalysts.
Enantioselective Formation of Cyano‐Bearing All‐Carbon Quaternary Stereocenters: Desymmetrization by Copper‐Catalyzed N‐Arylation
Authors: Zhou Fengtao , Cheng Gui‐Juan , Yang Wenqiang , Long Yan , Zhang Shasha , Wu Yun‐Dong , Zhang Xinhao , Cai Qian
Published: July 2014

The enantioselective construction of all‐carbon quaternary stereocenters is one of the most challenging fields in asymmetric synthesis. An asymmetric desymmetrization strategy offers an indirect and efficient method for the formation of all‐carbon stereocenters. An enantioselective formation of cyano‐bearing all‐carbon quaternary stereocenters in 1,2,3,4,‐tetrahydroquinolines and 2,3,4,5‐tetrahydro‐1H‐benzo[b]azepines by copper‐catalyzed desymmetric N‐arylation is demonstrated. The cyano group at the prochiral center plays a key role for the high enantioselectivity and works as an important functional group for further transformations. DFT studies provide a model which successfully accounts for the origin of enantioselectivity.
Highly Enantioselective Rhodium(I)‐Catalyzed Carbonyl Carboacylations Initiated by CC Bond Activation
Authors: Souillart Laetitia , Cramer Nicolai
Published: July 2014

The lactone motif is ubiquitous in natural products and pharmaceuticals. The Tishchenko disproportionation of two aldehydes, a carbonyl hydroacylation, is an efficient and atom‐economic access to lactones. However, these reaction types are limited to the transfer of a hydride to the accepting carbonyl group. The transfer of alkyl groups enabling the formation of CC bonds during the ester formation would be of significant interest. Reported herein is such asymmetric carbonyl carboacylation of aldehydes and ketones, thus affording complex bicyclic lactones in excellent enantioselectivities. The rhodium(I)‐catalyzed transformation is induced by an enantiotopic CC bond activation of a cyclobutanone and the formed rhodacyclic intermediate reacts with aldehyde or ketone groups to give highly functionalized lactones.
Statistical analysis of nanofibers alignment in magnetic‐field‐assisted electrospinning including an alignment percentage formula
Authors: Rahmani Shahrzad , Rafizadeh Mehdi , Afshar Taromi Framarz
Published: July 2014

Magnetic‐field‐assisted electrospinning (MFAES) is a simple and effective method to align polymer nanofibers. In this method, further research is needed to identify alignment mechanism. Hence, this article includes statistical analysis of affecting factors to investigate alignment mechanism in MFAES. Tip to target distance, magnets distance, voltage, and collection time, which are recognized as the most effective factors on nanofibers alignment, were applied in design of experiments. Central composite method was applied to get required experiments with designed expert 8 software. A response surface was proposed with regression coefficient of 97%. Then, the common physics concepts and statistical results were used to discuss the affecting mechanism of the electric and magnetic fields on the electrospinnig jet and the nanofibers alignment. Field emission scanning electron microscopy images were used to characterize the nanofibers alignment and calculate overall alignment percentage using a proposed statistical combinatorial weighted percentage formula. MFAES method, used in this research, achieved 95.3% polyacrylonitrile‐aligned nanofibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41179.
Impact of the coating process on the molecular structure of starch‐based barrier coatings
Authors: Menzel Carolin , Koch Kristine
Published: July 2014

Molecular analysis of starch structure can be used to explain and predict changes in physical properties, such as water vapor and oxygen barrier properties in packaging materials. Solution casting is a widely used technique to create films from starch formulations. This study compared the molecular properties of these standard films with those of experimental coatings applied to paper in laboratory‐scale and pilot‐scale trials, with all three techniques using the same starch formulation. The results revealed large differences in molecular structure, i.e., cross‐linking and hydrolysis, between films and coatings. The main differences were due to the shorter drying time allowed to laboratory‐scale coatings and the accelerated drying process in pilot trials owing to the high energy output of infrared dryers. Furthermore, surface morphology was highly affected by the coating technique used, with a rougher surface and many pinholes occurring in pilot‐scale coatings, giving lower water vapor permeability than laboratory‐scale coatings. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41190.
Polyaniline nanofibers for In situ MAO‐catalyzed polymerization of ethylene
Authors: de Souza Basso Nara Regina , Oliveira Felipo , Graebin Ana Paula , Moura Cássio Stein , de Carvalho Fim Fabiana , Galland Griselda Barrera , Bonnaud Leila , Murariu Oltea , Dubois Philippe
Published: July 2014

In this work electro‐conductive polyaniline nanofibers (PAni‐nanofibers) were prepared via interfacial methodology. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed that the synthesized PAni‐nanofibers present high aspect ratio with an average diameter of 80 nm, while they exhibit high conductivity (DC conductivity values: 4.19 ± 0.21 S cm−1). After specific treatment to remove moisture and remaining trapped HCl from PAni‐nanofibers, it was possible to prepare promising polyethylene (PE)/PAni composites by in situ polymerization of ethylene using bis(cyclopentadienyl) zirconium(IV) dichloride (Cp2ZrCl2) and methylaluminoxane (MAO) as catalytic system. More precisely, various contents of PAni‐nanofibers (from 0.2 to 7 wt %) were successfully incorporated in the in situ produced PE/PAni nanocomposites. PAni‐nanofibers were found to affect significantly the crystallization of the polyolefinic matrix while preserving its thermal stability. Preliminary measurements of electric properties showed PAni‐nanofibres are able to bring electro‐conductive properties to the in situ polymerized PE/PAni composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41197.
Ultrasound assisted continuous‐mixing for the preparation of PP/SEBS/OMMT ternary nanocomposites
Authors: Liu Ying , Xie Linsheng , Ma Yulu , Liu Haitao , Zhao Haili , Wang Yunxiang
Published: July 2014

Polypropylene (PP)/polystyrene‐block‐poly(ethylene‐co‐butylenes)‐block‐polystyrene (SEBS)/organo‐montmorillonite (OMMT) nanocomposites of varying concentrations of maleic anhydride‐grafted polypropylene (PP‐g‐MA) were prepared by continuous mixing assisted by ultrasonic oscillation. The structure and morphology of nanocomposites were investigated by X‐ray diffraction (XRD), transmission electron microscopy, and scanning electron microscopy. It was found that both PP‐g‐MA and ultrasonic oscillation could enhance the intercalation and exfoliation of OMMT in PP matrix. Meanwhile, the formation of
PP could be induced by ultrasonic irradiation at a power of more than 540 W. Rheological properties including complex viscosity, storage, and loss modulus of nanocomposites were increased after adding PP‐g‐MA or ultrasonic treatment. The results of mechanical properties showed that PP‐g‐MA could improve the tensile strength and tensile modulus of nanocomposites, but with the sacrifice of impact strength. This problem could be improved by ultrasound due to the reduced particle size of SEBS. However, the mechanical properties would be reduced by ultrasonic treatment with higher intensity due to the polymer degradation. Therefore, the synergistic effect of both compatibilizer and ultrasound should account for the balance between toughness and stiffness of PP/SEBS/OMMT ternary nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41202.
Journal maps, interactive overlays, and the measurement of interdisciplinarity on the basis of Scopus data (1996–2012)
Authors: Leydesdorff Loet , de Moya‐Anegón Félix , Guerrero‐Bote Vicente P.
Published: July 2014

Using Scopus data, we construct a global map of science based on aggregated journal–journal citations from 1996–2012 (N of journals = 20,554). This base map enables users to overlay downloads from Scopus interactively. Using a single year (e.g., 2012), results can be compared with mappings based on the Journal Citation Reports at the Web of Science (N = 10,936). The Scopus maps are more detailed at both the local and global levels because of their greater coverage, including, for example, the arts and humanities. The base maps can be interactively overlaid with journal distributions in sets downloaded from Scopus, for example, for the purpose of portfolio analysis. Rao‐Stirling diversity can be used as a measure of interdisciplinarity in the sets under study. Maps at the global and the local level, however, can be very different because of the different levels of aggregation involved. Two journals, for example, can both belong to the humanities in the global map, but participate in different specialty structures locally. The base map and interactive tools are available online (with instructions) at http://www.leydesdorff.net/scopus_ovl.
Remote Sulfonamido Group Enhances Reactivity and Selectivity for Asymmetric Michael Addition of Nitroalkanes to α,β‐Unsaturated Aldehydes
Authors: Huang Yu‐Chao , Uang Biing‐Jiun
Published: July 2014

The pyrrolidine–camphorsulfonamide‐based catalyst 1 a catalyzes the enantioselective conjugate addition of nitroalkanes to α,β‐unsaturated aldehydes in the presence of five equivalents of water in iPrOH to give the corresponding chiral Michael adducts in good yields and high enantioselectivities (up to 99 % ee) with a catalyst loading as low as 1 mol %.
Targeting cancer's weaknesses (not its strengths): Therapeutic strategies suggested by the atavistic model
Authors: Lineweaver Charles H. , Davies Paul C. W. , Vincent Mark D.
Published: July 2014

In the atavistic model of cancer progression, tumor cell dedifferentiation is interpreted as a reversion to phylogenetically earlier capabilities. The more recently evolved capabilities are compromised first during cancer progression. This suggests a therapeutic strategy for targeting cancer: design challenges to cancer that can only be met by the recently evolved capabilities no longer functional in cancer cells. We describe several examples of this target‐the‐weakness strategy. Our most detailed example involves the immune system. The absence of adaptive immunity in immunosuppressed tumor environments is an irreversible weakness of cancer that can be exploited by creating a challenge that only the presence of adaptive immunity can meet. This leaves tumor cells more vulnerable than healthy tissue to pathogenic attack. Such a target‐the‐weakness therapeutic strategy has broad applications, and contrasts with current therapies that target the main strength of cancer: cell proliferation.

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Preparation of carbon quantum dots based on starch and their spectral properties
Authors: Yan Zhengyu , Shu Juan , Yu Yan , Zhang Zhengwei , Liu Zhen , Chen Jianqiu
Published: July 2014

A simple method for the synthesis of water‐soluble carbon quantum dots (CQDs) has been developed based on chemical oxidation of starch. The structures and optical properties of the CQDs were characterized by ultraviolet–visible (UV–Vis) spectroscopy, photoluminescence spectroscopy (PL) and transmission electron microscopy. The CQDs were found to emit bright blue fluorescence and disperse uniformly. The effects of ambient temperature, light and pH on the properties of CQDs were studied. The CQDs exhibited good chemical stability, good photostability and pH sensitivity. Furthermore, the interaction between CQDs and bovine serum albumin (BSA) was investigated. Copyright © 2014 John Wiley & Sons, Ltd.