bluuebunny/crossref_metadata_2025 huggingface dataset:
Bayesian multistate models for measuring invasive carp movement and evaluating telemetry array performance
Authors: Stanton Jessica C. , Brey Marybeth K. , Coulter Alison A. , Stewart David R. , Knights Brent
Published: August 2024

Understanding the movement patterns of an invasive species can be a powerful tool in designing effective management and control strategies. Here, we used a Bayesian multistate model to investigate the movement of two invasive carp species, silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis), using acoustic telemetry. The invaded portions of the Illinois and Des Plaines Rivers, USA, are a high priority management zone in the broader efforts to combat the spread of invasive carps from reaching the Laurentian Great Lakes. Our main objective was to characterize the rates of upstream and downstream movements by carps between river pools that are maintained by navigation lock and dam structures. However, we also aimed to evaluate the efficacy of the available telemetry infrastructure to monitor carp movements through this system. We found that, on a monthly basis, most individuals of both species remained within their current river pools: averaging 76.2% of silver carp and 75.5% of bighead carp. Conversely, a smaller proportion of silver carp, averaging 14.2%, and bighead carp, averaging 13.9%, moved to downstream river pools. Movements towards upstream pools were the least likely for both species, with silver carp at an average of 6.7% and bighead carp at 7.9%. The highest probabilities for upstream movements were for fish originating from the three most downstream river pools, where most of the population recruitment occurs. However, our evaluation of the telemetry array’s effectiveness indicated low probability to detect fish in this portion of the river. We provide insights to enhance the placement and use of these monitoring tools, aiming to deepen our comprehension of these species’ movement patterns in the system.
On an energy‐latitude dispersion pattern of ion precipitation potentially associated with magnetospheric EMIC waves
Authors: Liang Jun , Donovan E. , Ni B. , Yue C. , Jiang F. , Angelopoulos V.
Published: September 2014

Ion precipitation mechanisms are usually energy dependent and contingent upon magnetospheric/ionospheric locations. Therefore, the pattern of energy‐latitude dependence of ion precipitation boundaries seen by low Earth orbit satellites can be implicative of the mechanism(s) underlying the precipitation. The pitch angle scattering of ions led by the field line curvature, a well‐recognized mechanism of ion precipitation in the central plasma sheet (CPS), leads to one common pattern of energy‐latitude dispersion, in that the ion precipitation flux diminishes at higher (lower) latitudes for protons with lower (higher) energies. In this study, we introduce one other systematically existing pattern of energy‐latitude dispersion of ion precipitation, in that the lower energy ion precipitation extends to lower latitude than the higher‐energy ion precipitation. Via investigating such a “reversed” energy‐latitude dispersion pattern, we explore possible mechanisms of ion precipitation other than the field line curvature scattering. We demonstrate via theories and simulations that the H‐band electromagnetic ion cyclotron (EMIC) wave is capable of preferentially scattering keV protons in the CPS and potentially leads to the reversed energy‐latitude dispersion of proton precipitation. We then present detailed event analyses and provide support to a linkage between the EMIC waves in the equatorial CPS and ion precipitation events with reversed energy‐latitude dispersion. We also discuss the role of ion acceleration in the topside ionosphere which, together with the CPS ion population, may result in a variety of energy‐latitude distributions of the overall ion precipitation.
Nuclear Magnetic Resonance as Analytical Tool for Crude Plant Extracts
Authors: Bilia Anna R.
Published: September 2014

Authentication, quality control, and stability testing of crude plant extracts are generally achieved and well established through HPLC, HPTLC, and capillary GC, using specific detectors such as UV–vis, RI, and coupled systems (MS), which allow the qualitative and quantitative determination of the composition of the markers or active substances. The major disadvantages of these conventional methods lie in the time consuming for the development of simple and rapid chromatographic separation and for the preparation of samples before measurements. In addition, these techniques are not able to reveal unknown plant metabolites that can contribute to the biological activity.

NMR spectroscopy is nondestructive, selective, and capable of simultaneous detection of a great number of constituents. The identification by NMR provides on both major and minor components, with no restrictions relating to volatility, polarity, or the presence of specific chromophores. Finally, the method can be applied without knowledge of the composition of the sample. NMR spectra contain information about the identity of the molecules in the extracts and are useful to quantify the constituents. NMR spectroscopy coupled with chemometric tools has been successfully applied to the characterization of various herbs and plant extracts for quality control, authentication, determining geographical origin, and detecting adulteration of herbal drugs and extracts.
Analysis of Plant Saponins
Authors: Krzyzanowska Justyna , Kowalczyk Mariusz , Oleszek Wieslaw
Published: September 2014

Saponins are naturally occurring secondary metabolites, which can be widely found in a number of plant families. They can be found in different parts of plants usually as multicomponent mixtures. They are composed of the triterpene or steroidal aglycone to which a number of sugars in the form of one, two, or three sugar chains are attached. Depending on the chemical structure, they show different biological activities. The common feature of these compounds is surface activity, so they can be used as emulsifiers, and in the past, they were used as soap substitutes. Some of them have found application in food industry, whereas the others are being considered as antinutritional substances. Owing to the fact that saponins occur in quite complex mixtures, their separation to individual compounds is still a challenge. Also, their determination with chromatographic techniques creates some problems as they are lacking chromophores allowing ultraviolet (UV) detection. Precolumn derivatization, light scattering detection, and liquid chromatography coupled with mass detector are the methods of choice for their determination.
Length Scale Selects Directionality of Droplets on Vibrating Pillar Ratchet
Authors: Agapov Rebecca L. , Boreyko Jonathan B. , Briggs Dayrl P. , Srijanto Bernadeta R. , Retterer Scott T. , Collier C. Patrick , Lavrik Nickolay V.
Published: September 2014

Directional control of droplet motion at room temperature is of interest for applications such as microfluidic devices, self‐cleaning coatings, and directional adhesives. Here, arrays of tilted pillars ranging in height from the nanoscale to the microscale are used as structural ratchets to directionally transport water at room temperature. Water droplets deposited onto vibrating chips with a nanostructured ratchet move preferentially in the direction of the feature tilt while the opposite directionality is observed in the case of microstructured ratchets. This remarkable switch in directionality is consistent with changes in the contact angle hysteresis. To glean further insights into the length scale dependent asymmetric contact angle hysteresis, the contact lines formed by a nonvolatile room temperature ionic liquid placed onto the tilted pillar arrays were visualized and analyzed in situ in a scanning electron microscope. The ability to tune droplet directionality by merely changing the length scale of surface features all etched at the same tilt angle would be a versatile tool for manipulating multiphase flows and for selecting droplet directionality in other lap‐on‐chip applications.
Transition Metal‐Free Intermolecular α‐CH Amination of Ethers at Room Temperature
Authors: Buslov Ivan , Hu Xile
Published: September 2014

We describe a new method for the intermolecular amination of the α‐CH bonds of ethers. A hypervalent iodine reagent was used as oxidant to enable the amination of cyclic and acyclic alkyl ethers with a wide range of amides, imides, and amines. The amination occurred at room temperature and without a transition metal catalyst. The method could be used to synthesize the anti‐cancer prodrug Tegafur and its analogues.

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Novel mutation in TSPAN12 leads to autosomal recessive inheritance of congenital vitreoretinal disease with intra‐familial phenotypic variability
Authors: Gal Moran , Levanon Erez Y. , Hujeirat Yasir , Khayat Morad , Pe'er Jacob , Shalev Stavit
Published: September 2014

Developmental malformations of the vitreoretinal vasculature are a heterogeneous group of conditions with various modes of inheritance, and include familial exudative vitreoretinopathy (FEVR), persistent fetal vasculature (PFV), and Norrie disease. We investigated a large consanguineous kindred with multiple affected individuals exhibiting variable phenotypes of abnormal vitreoretinal vasculature, consistent with the three above‐mentioned conditions and compatible with autosomal recessive inheritance. Exome sequencing identified a novel c.542G > T (p.C181F) apparently mutation in the TSPAN12 gene that segregated with the ocular disease in the family. The TSPAN12 gene was previously reported to cause dominant and recessive FEVR, but has not yet been associated with other vitreoretinal manifestations. The intra‐familial clinical variability caused by a single mutation in the TSPAN12 gene underscores the complicated phenotype‐genotype correlation of mutations in this gene, and suggests that there are additional genetic and environmental factors involved in the complex process of ocular vascularization during embryonic development. Our study supports considering PFV, FEVR, and Norrie disease a spectrum of disorders, with clinical and genetic overlap, caused by mutations in distinct genes acting in the Norrin/β‐catenin signaling pathway. © 2014 Wiley Periodicals, Inc.
Aquaporin expression profiles in normal sinonasal mucosa and chronic rhinosinusitis
Authors: Frauenfelder Claire , Woods Charmaine , Hussey Damian , Ooi Eng , Klebe Sonja , Carney A. Simon
Published: September 2014

Background

Thickened secretions, mucosal edema, and polyp formation are pathological features in chronic rhinosinusitis (CRS) that could theoretically be caused by aberrant water flow through sinonasal mucosa. Aquaporins (AQPs) are a family of proteins with roles in water transport, with tissue‐specific expression profiles. This study aims to determine if AQP expression in sinonasal mucosa is different between normal controls and patients with CRS, either with (CRSwNP) or without (CRSsNP) nasal polyps.

Methods

During endoscopic sinus surgery or transsphenoidal surgery, sinonasal tissue was collected and classified as CRSwNP (n = 13), CRSsNP (n = 10), or normal (n = 10). Messenger RNA (mRNA) expression of human AQP0 to AQP12b was determined using quantitative real‐time polymerase chain reaction (qRT‐PCR). Cellular localization of AQP1, AQP3, AQP4, AQP5, AQP7, and AQP11 was determined by immunohistochemistry.

Results

mRNA of AQP0 to AQP11 was identified in all samples. AQP12b mRNA was not detected. Significant differences in the mRNA expression levels of AQP4 and AQP11 were identified between normal and CRSwNP patients (p < 0.05). Differences in the cellular localization of AQPs were observed in both CRSsNP and CRSwNP patients vs normal controls. More intense localization to the cell cytoplasm was observed for AQP5 in glandular epithelium (CRSwNP; p < 0.05) and surface epithelium (CRSsNP; p < 0.05), and AQP4 in glandular epithelium (CRSsNP; p < 0.05).

Conclusion

This study characterized AQP mRNA expression and protein localization in normal human sinonasal tissue. Significant differences in mRNA expression were found for AQP4 and AQP11 in CRSwNP and differences in protein localization patterns of AQP4 and AQP5 were identified in both types of CRS.
Photocatalytic Generation of N‐Centered Hydrazonyl Radicals:  A Strategy for Hydroamination of β,γ‐Unsaturated Hydrazones
Authors: Hu Xiao‐Qiang , Chen Jia‐Rong , Wei Qiang , Liu Feng‐Lei , Deng Qiao‐Hui , Beauchemin André M. , Xiao Wen‐Jing
Published: September 2014

A visible‐light photocatalytic generation of N‐centered hydrazonyl radicals has been accomplished for the first time. This approach allows efficient intramolecular addition of hydrazonyl radical to terminal alkenes, thus providing hydroamination and oxyamination products in good yields. Importantly, the protocol involves deprotonation of an NH bond and photocatalytic oxidation to an N‐centered radical, thus obviating the need to prepare photolabile amine precursors or the stoichiometric use of oxidizing reagents.
Enantioselective Synthesis of a Chiral Coordination Polymer with Circularly Polarized Visible Laser
Authors: Wu Shu‐Ting , Cai Zhen‐Wen , Ye Qiao‐Yan , Weng Chen‐Hao , Huang Xi‐He , Hu Xiao‐Lin , Huang Chang‐Cang , Zhuang Nai‐Feng
Published: September 2014

Circular dichroism is known to be the feature of a chiral agent which has inspired scientist to study the interesting phenomena of circularly polarized light (CPL) modulated molecular chirality. Although several organic molecules or assemblies have been found to be CPL‐responsive, the influence of CPL on the assembly of chiral coordination compounds remains unknown. Herein, a chiral coordination polymer, which is constructed from achiral agents, was used to study the CPL‐induced enantioselective synthesis. By irradiation with either left‐handed or right‐handed CPL during the reaction and crystallization, enantiomeric excesses of the crystalline product were obtained. Left‐handed CPL resulted in crystals with a left‐handed helical structure, and right‐handed CPL led to crystals with a right‐handed helical structure. It is exciting that the absolute asymmetric synthesis of a chiral coordination polymer could be enantioselective when using CPL, and provides a strategy for the control of the chirality of chiral coordination polymers.
Synthesis of Extended π‐Systems through C–H Activation
Authors: Segawa Yasutomo , Maekawa Takehisa , Itami Kenichiro
Published: September 2014

Activation of aromatic CH bonds by a transition metal catalyst has received significant attention in the synthetic chemistry community. In recent years, rapid and site‐selective extension of π‐electron systems by C–H activation has emerged as an ideal methodology for preparing organic materials with extended π‐systems. This Review focuses on recently reported π‐extending C–H activation reactions directed toward new optoelectronic conjugated materials.
Formation and Rearrangement of Homoserine Depsipeptides and Depsiproteins in the α‐Ketoacid–Hydroxylamine Ligation with 5‐Oxaproline
Authors: Wucherpfennig Thomas G. , Rohrbacher Florian , Pattabiraman Vijaya R. , Bode Jeffrey W.
Published: September 2014

The primary products of the chemical ligation of α‐ketoacids and 5‐oxaproline peptides are esters, rather than the previously reported amides. The depsipeptide product rapidly rearranges to the amide in basic buffers. The formation of esters sheds light on possible mechanisms for the type II KAHA ligations and opens an avenue for the chemical synthesis of depsiproteins.
Tuning the Selectivity of Photocatalytic Synthetic Reactions Using Modified TiO2 Nanotubes
Authors: Tripathy Jyotsna , Lee Kiyoung , Schmuki Patrik
Published: September 2014

Differently modified TiO2 nanotubes were used to achieve a drastic change in the selectivity of a photocatalytic reaction. For the photocatalytic oxidation of toluene, depending on the electronic properties of TiO2 (anatase, rutile, Ru‐doped), a strong change in the main reaction product (namely benzoic acid versus benzaldehyde) can be achieved, and certain undesired reaction pathways can be completely shut down.
Traceless Preparation of C‐Terminal α‐Ketoacids for Chemical Protein Synthesis by α‐Ketoacid–Hydroxylamine Ligation: Synthesis of SUMO2/3
Authors: Wucherpfennig Thomas G. , Pattabiraman Vijaya R. , Limberg Felix R. P. , Ruiz‐Rodríguez Javier , Bode Jeffrey W.
Published: September 2014

A novel protecting group for enantiopure α‐ketoacids delivers C‐terminal peptide α‐ketoacids directly upon resin cleavage and allows the inclusion of all canonical amino acids, including cysteine and methionine. By using this approach, SUMO2 and SUMO3 proteins were prepared by KAHA ligation with 5‐oxaproline. The synthetic proteins containing homoserine residues were recognized by and conjugated to RanGAP1 by SUMOylation enzymes.
Semisynthesis of Biologically Active Glycoforms of the Human Cytokine Interleukin 6
Authors: Reif Andreas , Siebenhaar Sebastian , Tröster Andrea , Schmälzlein Marina , Lechner Carolin , Velisetty Phanindra , Gottwald Karen , Pöhner Claudia , Boos Irene , Schubert Volker , Rose‐John Stefan , Unverzagt Carlo
Published: September 2014

Human interleukin 6 (IL‐6) is a potent cytokine with immunomodulatory properties. As the influence of N‐glycosylation on the in vivo activities of IL‐6 could not be elucidated so far, a semisynthesis of homogeneous glycoforms of IL‐6 was established by sequential native chemical ligation. The four cysteines of IL‐6 are convenient for ligations and require only the short synthetic glycopeptide 43–48. The Cys‐peptide 49–183 could be obtained recombinantly by cleavage of a SUMO tag. The fragment 1–42 was accessible by the simultaneous cleavage of two inteins, leading to the 1–42 thioester with the native N‐terminus. Ligation and refolding studies showed that the inherently labile AspPro bond 139–140 was detrimental for the sequential C‐ to N‐terminal ligation. A reversed ligation sequence using glycopeptide hydrazides gave full‐length IL‐6 glycoproteins, which showed full bioactivity after efficient refolding and purification.
Carbon Dioxide Reduction to Methylamines under Metal‐Free Conditions
Authors: Blondiaux Enguerrand , Pouessel Jacky , Cantat Thibault
Published: September 2014

The first metal‐free catalysts are reported for the methylation of amines with carbon dioxide. Proazaphosphatrane superbases prove to be highly active catalysts in the reductive functionalization of CO2, in the presence of hydroboranes. The new methodology enables the methylation of NH bonds in a wide variety of amines, including secondary amines, with increased chemoselectivity.
Synergistic effects of N, N′‐bis (benzoyl) sebacic acid dihydrazide and talc on the physical and mechanical behaviors of poly(l‐latic acid)
Authors: Xiao Hongqin , Guo Dan , Bao Jianjun
Published: September 2014

The important practical problem of poor heat stability of poly(l‐lactic acid) (PLLA) is addressed by the addition of N, N′‐bis (benzoyl) sebacic acid dihydrazide (BSAD) and talc as a nucleating agent system. The idea of incorporating talc into the PLLA/BSAD composites is that talc can provide supplementary nucleation effect with very small amount of BSAD (0.2 wt %) and therefore can improve the heat deflection resistance of PLLA materials. Effects of BSAD/talc on morphology, crystallization behavior, heat resistance, and mechanical properties of PLLA/BSAD/talc were investigated after annealing processes. The results indicated that the BSAD/talc system increased the crystallinity from 6.0% of pure PLLA to a maximum 42.9% by the synergistic effects of BSAD and talc increasing the growth of spherulites and nucleation density, respectively. After annealing at different temperatures, the heat deflection temperature (HDT) of PLLA was improved dramatically due to synergistic effects of BSAD/talc between restricted chain movement and acceleration of crystallization. At high temperature (above Tg), the thermo‐mechanical properties of PLLA is mainly determined by the crystallinity and the reinforcement effect of talc acted as a filler. Moreover, effects of BSAD/talc on mechanical properties were discussed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41454.
Efficient Synthesis of Frutinone A and Its Derivatives through Palladium‐Catalyzed CH Activation/Carbonylation
Authors: Shin Yongje , Yoo Changho , Moon Youngtaek , Lee Yunho , Hong Sungwoo
Published: September 2014

Frutinone A, a biologically active ingredient of an antimicrobial herbal extract, demonstrates potent inhibitory activity towards the CYP1A2 enzyme. A three‐step total synthesis of frutinone A with an overall yield of 44 % is presented. The construction of the chromone‐annelated coumarin core was achieved through palladium‐catalyzed CH carbonylation of 2‐phenolchromones. The straightforward synthetic route allowed facile substitutions around the frutinone A core and thus rapid exploration of the structure–activity relationship (SAR) profile of the derivatives. The inhibitory activity of the synthesized frutinone A derivatives were determined for CYP1A2, and ten compounds exhibited one‐to‐two digit nanomolar inhibitory activity towards the CYP1A2 enzyme.
The oscillation of the perturbation potential energy between the extratropics and tropics in boreal winter
Authors: Wang Lei , Li Jianping , Wang Zhanggui , Li Yanjie , Zheng Fei
Published: September 2014

Correlation analyses reveal that the perturbation potential energy (PPE) in the extratropics and tropics in boreal winters undergoes out‐of‐phase oscillations (PPE1 extratropics–tropics oscillation, PETO). PETO is closely related to both El Niño‐Southern Oscillation (ENSO) and kinetic energy, furthermore, PETO tends to dominate over the extratropics while ENSO is more important over the tropics. In the Northern (Southern) Hemisphere, positive PETO phases tend to strengthen (weaken) Hadley circulation and to weaken (strengthen) an expanded Ferrel circulation, resulting in equatorward shift of the subtropical jet streams. In addition, precipitation is enhanced in regions of ascending vertical motion, and warmer temperatures are observed in the tropics except over the western Pacific.
An investigation into the architecture of the vastus medialis oblique muscle in athletic and sedentary individuals: An in vivo ultrasound study
Authors: Benjafield A.J. , Killingback A. , Robertson C.J. , Adds P.J.
Published: September 2014

There is thought to be a relationship between the vastus medialis oblique muscle (VMO) and patellofemoral pain syndrome (PFPS), a condition that has a high prevalence in young athletic individuals. Following a suggestion that there may be a link between the architecture of the VMO and an individual's activity level, the aim of this study was to determine any differences in two measurable parameters of the VMO between two populations with widely differing activity levels. The parameters measured were VMO fiber angle and insertion ratio, which is the proportion of the medial patellar border with VMO fibers inserting onto it (%). Eighty‐two knees from 26 athletic volunteers and 15 sedentary volunteers (aged 20–28 years) were assessed using ultrasound. Activity level was defined using the Tegner scoring system. The mean VMO angle (°) for the athletic group was significantly higher than for the sedentary group at 67.8° and 53.6°, respectively. There was no significant difference in insertion ratio between the athletic group, 43.0%, and the sedentary group, 39.5%. This study found that greater VMO fiber angles were seen in individuals with higher activity levels, exerting a stronger medial stabilizing force on the patella. This has important implications for the treatment of PFPS, particularly in athletic patients, which frequently focus on VMO strengthening exercises. Clin. Anat. 28:262–268, 2015. © 2014 Wiley Periodicals, Inc.
Degradable Hybrid Materials Based on Cationic Acylhydrazone Dynamic Covalent Polymers Promote DNA Complexation through Multivalent Interactions
Authors: Bouillon Camille , Paolantoni Delphine , Rote Jennifer C. , Bessin Yannick , Peterson Larryn W. , Dumy Pascal , Ulrich Sébastien
Published: September 2014

The design of smart nonviral vectors for gene delivery is of prime importance for the successful implementation of gene therapies. In particular, degradable analogues of macromolecules represent promising targets as they would combine the multivalent presentation of multiple binding units that is necessary for achieving effective complexation of therapeutic oligonucleotides with the controlled degradation of the vector that would in turn trigger drug release. Toward this end, we have designed and synthesized hybrid polyacylhydrazone‐based dynamic materials that combine bis‐functionalized cationic monomers with ethylene oxide containing monomers. Polymer formation was characterized by 1H and DOSY NMR spectroscopy and was found to take place at high concentration, whereas macrocycles were predominantly formed at low concentration. HPLC monitoring of solutions of these materials in aqueous buffers at pH values ranging from 5.0 to 7.0 revealed their acid‐catalyzed degradation. An ethidium bromide displacement assay and gel electrophoresis clearly demonstrated that, despite being dynamic, these materials are capable of effectively complexing dsDNA in aqueous buffer and biological serum at N/P ratios comparable to polyethyleneimine polymers. The self‐assembly of dynamic covalent polymers through the incorporation of a reversible covalent bond within their main chain is therefore a promising strategy for generating degradable materials that are capable of establishing multivalent interactions and effectively complexing dsDNA in biological media.
Exchange‐Coupled fct‐FePd/α‐Fe Nanocomposite Magnets Converted from Pd/Fe3O4 Core/Shell Nanoparticles
Authors: Liu Fei , Dong Yunhe , Yang Wenlong , Yu Jing , Xu Zhichuan , Hou Yanglong
Published: September 2014

We report the controlled synthesis of exchange‐coupled face‐centered tetragonal (fct) FePd/α‐Fe nanocomposite magnets with variable Fe concentration. The composite was converted from Pd/Fe3O4 core/shell nanoparticles through a high‐temperature annealing process in a reducing atmosphere. The shell thickness of core/shell Pd/Fe3O4 nanoparticles could be readily tuned, and subsequently the concentration of Fe in nanocomposite magnets was controlled. Upon annealing reduction, the hard magnetic fct‐FePd phase was formed by the interdiffusion between reduced α‐Fe and face‐centered cubic (fcc) Pd, whereas the excessive α‐Fe remained around the fct‐FePd grains, realizing exchange coupling between the soft magnetic α‐Fe and hard magnetic fct‐FePd phases. Magnetic measurements showed variation in the magnetic properties of the nanocomposite magnets with different compositions, indicating distinct exchange coupling at the interfaces. The coercivity of the exchange‐coupled nanocomposites could be tuned from 0.7 to 2.8 kOe and the saturation magnetization could be controlled from 93 to 160 emu g−1. This work provides a bottom‐up approach using exchange‐coupled nanocomposites for engineering advanced permanent magnets with controllable magnetic properties.
Methanol production by bi‐reforming
Authors: Santos Bruno A. V. , Loureiro José M. , Ribeiro Ana M. , Rodrigues Alírio E. , Cunha Adelino F.
Published: September 2014

Population growth and emerging economies have as consequence increasing energy demands associated with fossil fuel depletion and environmental impacts. A new philosophy emerges: the concept of green chemistry. Carbon dioxide, a well‐known greenhouse gas, is a source for the production of fine chemicals and fuels such as methanol. It appears in abundance due to anthropogenic human activities. Nowadays, methanol is typically produced from synthesis‐gas which requires conventional fossil fuels; however, the availability of these fuels is limited. As an alternative, the vent streams of steam reforming units, which are rich in carbon dioxide and steam, can be used together with methane (natural gas) in a bi‐reforming process for methanol synthesis. The essential idea is that carbon dioxide and water are recycled like in a synthetic photosynthesis process.
Synaptic connections of first‐stage visual neurons in the locust Schistocerca gregaria extend evolution of tetrad synapses back 200 million years
Authors: Wernitznig Stefan , Rind Frances Claire , Pölt Peter , Zankel Armin , Pritz Elisabeth , Kolb Dagmar , Bock Elisabeth , Leitinger Gerd
Published: September 2014

The small size of some insects, and the crystalline regularity of their eyes, have made them ideal for large‐scale reconstructions of visual circuits. In phylogenetically recent muscomorph flies, like Drosophila, precisely coordinated output to different motion‐processing pathways is delivered by photoreceptors (R cells), targeting four different postsynaptic cells at each synapse (tetrad). Tetrads were linked to the evolution of aerial agility. To reconstruct circuits for vision in the larger brain of a locust, a phylogenetically old, flying insect, we adapted serial block‐face scanning electron microscopy (SBEM). Locust lamina monopolar cells, L1 and L2, were the main targets of the R cell pathway, L1 and L2 each fed a different circuit, only L1 providing feedback onto R cells. Unexpectedly, 40% of all locust R cell synapses onto both L1 and L2 were tetrads, revealing the emergence of tetrads in an arthropod group present 200 million years before muscomorph flies appeared, coinciding with the early evolution of flight. J. Comp. Neurol. 523:298–312, 2015. © 2014 Wiley Periodicals, Inc.
An optical model relating (L*a*b*) values for a scattering surface covered with a scattering layer to (L*a*b*) values for the uncovered surface and its application to tooth colour
Authors: Battersby Stephen J. , Battersby Paul D.
Published: September 2014

The appearance of human dentition is important both psychologically and commercially. Many people perceive the lightness and chromaticity of their teeth as key factors in their overall appearance leading to large businesses in materials for colour‐matched fillings and crowns and in tooth whitening products. The human eye is very sensitive to small colour differences, recognizing a row of highly colour‐matched crowns as unnatural yet seeing excessive colour variation or darkness as unattractive. One cause of tooth discolouration is a darkening of the dentine, visible through the enamel. This has lead the authors to develop a model capable of relating (
) measurements on a scattering surface, in our case dentine, to (
) measurements when overlaid by a translucent scattering layer, in our case tooth enamel. The model can be used when any scattering layer is superimposed on a coloured surface. In contrast to existing models, no spectral measurements are necessary allowing the use of colourimeters rather than spectrophotometers. However, there are limitations on the degree of colour saturation for both the coloured surface and the scattering layer as the model uses an approximation valid only for weakly saturated colours. As neither the enamel nor the dentine have strongly saturated colouration, the limitation is entirely acceptable for our work. The use of (
) measurements directly rather than having to measure the spectrum of reflected light is of practical importance as such measurements in a dental surgery are impossible in all but exceptional cases whilst (
) measurements in the surgery are routine. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 504–517, 2015
Structure–Activity Relationships of Glycogen Phosphorylase Inhibitor FR258900 and Its Analogues: A Combined Synthetic, Enzyme Kinetics, and Computational Study
Authors: Juhász László , Varga Gergely , Sztankovics Andrea , Béke Ferenc , Docsa Tibor , Kiss‐Szikszai Attila , Gergely Pál , Kóňa Juraj , Tvaroška Igor , Somsák László
Published: September 2014

Invited for this month’s cover are a group of collaborators from the University of Debrecen (L. Somsák and P. Gergely) and the Institute of Chemistry of the Slovak Academy of Sciences (I. Tvaroška). The cover picture shows the natural product FR258900, some synthetic analogues, and the binding of the most active inhibitor to the allosteric site of the enzyme. Read the full text of the article at 10.1002/cplu.201402181
Quantized control for polynomial fuzzy discrete‐time systems
Authors: Zhou Qi , Chen Ziran , Li Xinchen , Gao Yabin
Published: September 2014

This article investigates the
control problem for polynomial fuzzy discrete‐time systems. Signal quantization is considered in this article. To deal with this issue, a logarithmic quantizer is adopted to quantize the control signal. First, a novel method is first proposed to model polynomial fuzzy discrete‐time systems and handle the quantized control problem of the systems. Second, based on Lyapunov‐stability theory, sufficient conditions are obtained in terms of sum of squares to guarantee the asymptotical stability of the systems and satisfy a
performance. Finally, a simulation example is given to illustrate the effectiveness of the proposed results. © 2014 Wiley Periodicals, Inc. Complexity 21: 325–332, 2015
An initial evaluation of drone‐based monitoring of boulder beaches in Galicia, north‐western Spain
Authors: Pérez‐Alberti Augusto , Trenhaile Alan S.
Published: September 2014

Low altitude flights by a micro‐drone were made in 2012 and 2013 over two boulder beaches in north‐western Spain. Geographical information system software was used to map the data. Boulder outlines from the first flight were recorded on 4796 clasts at Laxe Brava and 2508 clasts at Oia. Changes in location were identified by overlaying these outlines on the 2013 images. About 17.5% of the boulders (mean surface area 0.32 m2) moved at Laxe Brava and about 53% (mean surface area 0.23 m2) at Oia. Most movement on both beaches was between the mid‐tide to about 2 m above the high tidal level. The location and elevation of the highest points were also recorded on the 2012 images on 4093 boulders at Laxe Brava and 3324 boulders at Oia. These elevations were compared with the elevations at the same locations in 2013. The occurrence and scale of the elevational changes were generally consistent with changes in the boulder outlines. The study confirmed that boulder beaches can be cheaply and effectively monitored using high resolution, micro‐drone technology. Copyright © 2014 John Wiley & Sons, Ltd.
Over the Hedge: Do Exporters Practice Selective Hedging?
Authors: Fabling Richard , Grimes Arthur
Published: September 2014

What determines exporters’ exchange rate hedging decisions and do exporters attempt to “time the market?” We use a unique longitudinal dataset on firm exports to find the determinants of exporters’ currency hedging choices. Determinants include financial fragility, prior hedging experience, and natural hedge opportunities. We also find that firms alter their hedging ratios when the currency has recently trended in one direction. This behavior is ubiquitous for all but large firms and for all times other than when the exchange rate is near its extreme historical values. These results are consistent with most firms exhibiting (sub‐optimal) selective hedging behavior. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:321–338, 2015
Business Strategies: Increasing Brand Trust Among Utility Customers Lowers Costs and Turnover
Authors: Oberle Chris
Published: September 2014

Interactions between utilities and customers have evolved over time from those that were once largely transactional and service‐based to those that are now initiative‐ and relationship‐oriented. This migration makes it clear that new tools for measuring the full strength of a utility's bond with customers are needed. Accordingly, research recently completed by Market Strategies International indicates that in addition to delivering on traditional operational satisfaction and product experience, utilities must deliver on a third factor—brand trust—if they are to develop strong and engaged relationships with their customers.
Conjugate Heat Transfer Analysis for a Finite Thickness Cylinder in a Hypersonic Flow
Authors: Peetala Ravi K. , Das Dipankar , Kulkarni Vinayak , Sahoo Niranjan
Published: September 2014

Prediction of surface heating rates is of prime importance for the hypersonic flow regime. Experimental and conventional computational efforts overlook the heat transfer phenomenon in the solid due to the rigid assumptions involved in the solution methodologies. In order to address this fact, conjugate heat transfer (CHT) studies are carried out using various coupling techniques to examine their implementation abilities. Three types of solution methodologies are adopted, namely, decoupled, strongly coupled, and loosely coupled analysis. This study is also focused on looking into the effect of a hypersonic flow field on wall heat flux for a finite thickness insulating cylinder at moderately large time scales. Increase in wall temperature and decrease in surface heat flux have been noticed using strong and loose coupling techniques with an increase in simulation time. Decoupled fluid and solid domain analysis is found to be useful for typical shock tunnel test durations (∼1 ms) while investigations with loose coupling techniques are advisable for time scales corresponding to flight testing (∼1 s). Efforts are also made to reason the discrimination in prediction of stagnation point heat flux using conventional computational and experimental analysis.
Nanopillar, Nanowall, and Nanowire Devices for Fast Separation of Biomolecules
Authors: Yasui Takao , Rahong Sakon , Kaji Noritada , Baba Yoshinobu
Published: September 2014

Nanostructures based on nanotechnologies have opened up a novel research field for the fast analysis of biomolecules with ultrahigh resolution, including the analysis of single biomolecules. Nanostructures for electrophoretic separation, especially, are an exciting topic among researchers in many areas, and their designs are widely expected to contribute to the goal of developing a single separation tool for a wide range of biomolecules. In this review, nanopillar, nanowall, and nanowire devices are introduced for fast separation of DNA molecules and protein samples, and the numerous advantages of these devices are described. This review also outlines the fabrication processes for nanostructures, including “top‐down” and “bottom‐up” nanofabrication approaches. Besides describing the fast separation of biomolecules, the electroosmotic flow (EOF) suppression effect, and its related online concentration technique in nanopillar devices, is reviewed. The nanowall devices have the unique feature that longer DNA molecules migrate faster than shorter ones, and that is completely different from the separation behavior of DNA molecules based on nanopillar devices. The feasibility is shown for self‐assembly of the nanowire structure embedded in a microchannel on a fused silica substrate, as a means to separate DNA molecules. Applications of a newly‐fabricated 3D network structure with spatial density control for the fast separation of a wide range of DNA molecules are also given.
CHARACTERISTICS OF EXAMINEES WHO LEAVE QUESTIONS UNANSWERED ON THE GRE GENERAL TEST UNDER RIGHTS‐ONLY SCORING
Authors: Grandy Jerilee
Published: September 2014

The purpose of the study was to determine why some examinees taking the GRE General Test leave items blank when they have been told that they will not be penalized for guessing and have been instructed to guess on questions they cannot answer.

Data from the October 1984 test administration were analyzed to establish whether nonguessers were different in any way from those who completed, or nearly completed, each test section. Nonguessers were defined as examinees who left large numbers of items blank, whether by omitting or by not finishing a test section. The analyses in this study did not separate these two ways of leaving items blank. A sample of non‐guessers was also surveyed by mail to determine whether they understood the instructions and why they omitted items.

The tendency to leave items blank was most evident among the following groups of examinees:

women

non‐Whites, particularly Blacks

resident aliens or foreign non‐citizens

members of families with less than average formal education

older examinees

examinees who were out of school or already in graduate school

examinees who had taken the GRE previously, under old instructions

examinees planning to study humanities or social sciences

examinees with lower than average undergraduate grades

examinees with lower than average GRE scores, even when the scores were corrected for not guessing

In regression analyses, GRE scores provided the best estimate of number of items left unanswered. For the verbal section, ethnicity was the second best predictor. Age, sex, and GPA made small but significant contributions to the equation. For the quantitative section, age was the second best predictor after test score, with sex and ethnicity each contributing a small amount. The analytical score was also predicted best by test score and second by age. Ethnicity and GPA provided small but significant weights.

Survey results suggested that many nonguessers did not fully understand guessing strategies and may have been confused by the new instructions because they conflicted with what the examinees had learned earlier. Their questionnaire responses were often inconsistent, and many claimed to have read and heard instructions not to guess.
REMOTE SCORING OF ESSAYS
Authors: Breland Hunter M. , Jones Robert J.
Published: September 2014

Essays written by college freshmen on two different topics were scored first by readers working in a conference setting and second by another set of readers working in their own homes or offices. The conference readers were trained in the standard manner on the specific topics to be scored and were monitored by table leaders, as is done in standard scoring procedures. The remote readers received only written instructions in the mail and there was no monitoring of their scoring. Analyses of the reliability and validity of the two scoring methods were then conducted.

Reliability comparisons favored the conference method over the remote method (.75 for conference scoring versus an average of .62 for remote scoring of two essays by three readers). Validity was assessed through multiple correlations with two criteria: (1) a four‐essay criterion, with each essay scored by three readers different from those who scored the essays being examined, and (2) freshman English course grade. The conference scores yielded a slightly higher average multiple correlation with the four‐essay criterion than did the remote scores (.67 versus .63), but for the English course grade criterion the average multiple correlation was the same for both types of scoring (.50). Average incremental validity (the contribution of essay score over and beyond the multiple correlation using multiple‐choice scores—TSWE and ECT) was .06 for the conference scoring and .05 for the remote scoring when the four‐essay criterion was used.

The remote scores were also statistically calibrated by adjusting scores for reader tendencies. These calibrations were effective in reducing score discrepancies, and reliabilities and validities were increased slightly as a result of the calibrations.

The comparisons conducted suggest some promise for remote scoring, especially if more sophisticated calibration procedures can be developed and if improved reader monitoring can be implemented, but with current procedures remote scoring is not as effective as conference scoring. Under certain circumstances, however, where cost or convenience may be relatively more important than reliability and validity, remote scoring may be preferable to conference scoring.
STATISTICAL APPROACHES TO THE STUDY OF ITEM DIFFICULTY
Authors: Olson John F. , Scheuneman Janice , Grima Angela
Published: September 2014

Traditionally, item difficulty has been defined in terms of the performance of examinees. For test development purposes, a more useful concept would be some kind of intrinsic item difficulty, defined in terms of the item's content, context, or characteristics and the task demands set by the item. To the extent that we can come to understand more fully the intrinsic difficulty of items, we can also begin to understand better the functioning of test items and to bring that functioning increasingly under control. An important step in developing the knowledge base required to acquire an understanding of those item properties that affect difficulty is appropriate analyses of existing test data. In this investigation, the measurement literature was surveyed for statistical approaches which might be fruitfully applied to the study of item difficulty. Two broad methodological approaches were identified: exploratory and confirmatory approaches. Exploratory methods were those that attempt to categorize or cluster items that appear to measure similar abilities and that function in a similar manner in order to determine their common characteristics as well as those that differentiate them from other items not in the cluster. Confirmatory methods would be applied to test hypotheses developed from exploratory results or from psychological theory. Described in the final section of the paper are the results of analyses using real test data that assessed the usefulness of two of the exploratory methods.
Purification and characterization of cloned alkaline protease gene of Geobacillus stearothermophilus
Authors: Iqbal Irfana , Aftab Muhammad Nauman , Afzal Mohammed , Ur‐Rehman Asad , Aftab Saima , Zafar Asma , Ud‐Din Zia , Khuharo Ateeque Rahman , Iqbal Jawad , Ul‐Haq Ikram
Published: September 2014

Thermostable alkaline serine protease gene of Geobacillus stearothermophilus B‐1172 was cloned and expressed in Escherichia coli BL21 (DE3) using pET‐22b(+), as an expression vector. The growth conditions were optimized for maximal production of the protease using variable fermentation parameters, i.e., pH, temperature, and addition of an inducer. Protease, thus produced, was purified by ammonium sulfate precipitation followed by ion exchange chromatography with 13.7‐fold purification, with specific activity of 97.5 U mg−1, and a recovery of 23.6%. Molecular weight of the purified protease, 39 kDa, was determined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). The enzyme was stable at 90 °C at pH 9. The enzyme activity was steady in the presence of EDTA indicating that the protease was not a metalloprotease. No significant change in the activity of protease after addition of various metal ions further strengthened this fact. However, an addition of 1% Triton X‐100 or SDS surfactants constrained the enzyme specific activity to 34 and 19%, respectively. Among organic solvents, an addition of 1‐butanol (20%) augmented the enzyme activity by 29% of the original activity. With casein as a substrate, the enzyme activity under optimized conditions was found to be 73.8 U mg−1. The effect of protease expression on the host cells growth was also studied and found to negatively affect E. coli cells to certain extent. Catalytic domains of serine proteases from eight important thermostable organisms were analyzed through WebLogo and found to be conserved in all serine protease sequences suggesting that protease of G. stearothermophilus could be beneficially used as a biocontrol agent and in many industries including detergent industry.