bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen controlled iron catalyst phase during carbon nanotube growth
Authors: Bayer Bernhard C. , Baehtz Carsten , Kidambi Piran R. , Weatherup Robert S. , Mangler Clemens , Kotakoski Jani , Goddard Caroline J. L. , Caneva Sabina , Cabrero-Vilatela Andrea , Meyer Jannik C. , Hofmann Stephan
Published: October 2014

Close control over the active catalyst phase and hence carbon nanotube structure remains challenging in catalytic chemical vapor deposition since multiple competing active catalyst phases typically co-exist under realistic synthesis conditions. Here, using in-situ X-ray diffractometry, we show that the phase of supported iron catalyst particles can be reliably controlled via the addition of NH3 during nanotube synthesis. Unlike polydisperse catalyst phase mixtures during H2 diluted nanotube growth, nitrogen addition controllably leads to phase-pure γ-Fe during pre-treatment and to phase-pure Fe3C during growth. We rationalize these findings in the context of ternary Fe-C-N phase diagram calculations and, thus, highlight the use of pre-treatment- and add-gases as a key parameter towards controlled carbon nanotube growth.
Dynamic characteristics of undoped and p-doped Fabry-Perot InAs/InP quantum dash based ridge waveguide lasers for access/metro networks
Authors: Mollet O. , Martinez A. , Merghem K. , Joshi S. , Provost J.-G. , Lelarge F. , Ramdane A.
Published: October 2014

In this paper, we report the characteristics of InAs/InP quantum dashes (QDash) based lasers emitting around 1.55 μm. An unprecedented high modal gain of ∼100 cm−1 is obtained for an optimized active structure by stacking 12 QDash layers. Directly modulated lasers allowed achieving a modulation bandwidth of ∼10 GHz and a Henry factor around 5. Thanks to p-type doping, the Henry factor value is reduced down to 2.7 while the modulation bandwidth still amounts to ∼10 GHz. This shows that doping of the active region is important to improve the dynamic characteristics of QDash lasers.
Predator recognition and responses in the endangered Macquarie perch (Macquaria australasica)
Authors: Brown Culum , Morgan Jennifer
Published: October 2014

Macquarie perch, Macquaria austalasica, is an endangered species endemic to southern Australia whose distribution is highly fragmented and continues to decline. Key threatening processes include habitat destruction, dams and weirs, overfishing and interactions with introduced species. Here, we examined the responses of small and large Macquarie perch to two native predators and to the introduced redfin perch, Perca fluviatilis. Our results showed that Macquarie perch generally avoided large-bodied native predators but was attracted to small-bodied native predators. Responses to large and small redfin perch lay between these two extremes, suggesting that the Macquarie perch does treat these foreign fish as potential threats. Macquarie perch relied on both visual and chemical cues to identify predators, although its response tended to be stronger when exposed to visual cues. The results suggest that Macquarie perch has the capacity to recognise and respond to invasive species in a threat-sensitive manner, which has positive implications for the conservation management of the species.
Effect of a rainfall pulse on phytoplankton bloom succession in a hyper-eutrophic subtropical lagoon
Authors: Meng Pei-Jie , Lee Hung-Jen , Tew Kwee Siong , Chen Chung-Chi
Published: October 2014

In the present study, we sought to understand the succession of phytoplankton species, after a natural nutrient pulse, in a subtropical lagoon located in southern Taiwan. The lagoon was surrounded by aquaculture ponds. The present study was performed during the wet summer season, before and after an episode of heavy precipitation. Before rainfall commenced, both the phosphate concentration and the level of phytoplankton were relatively low. After heavy precipitation, physical and chemical measurements indicated that significant amounts of dissolved inorganic nutrients had drained into the lagoon. A phytoplankton bloom occurred; organism levels reached 77.6×105 cells L–1. The dominant organism was Chaetoceros curvisetus (99.3%). After the bloom ceased, the levels of inorganic nutrients, especially silicate, fell. Phytoplankton became of low abundance once more. At the end of our study period, the ecosystem was dominated once more by diatoms (75.8%); this may have been caused by a low-level nutrient pulse following rainfall that occurred one day before final sampling. Overall, our results suggest that the bloom succession of phytoplankton species was principally dependent on nutrient dynamics in the lagoon, which was associated with nutrients discharged from drainage after heavy rainfall.
Who‘s cheating? Agreements about sexual exclusivity and subsequent concurrent partnering in Australian heterosexual couples
Authors: Richters Juliet , Heywood Wendy , Pitts Marian K. , Shelley Julia M. , Simpson Judy M. , Patrick Kent , Smith Anthony M. A.
Published: October 2014

Background Concurrent relationships are a driver of generalised epidemics of sexually transmissible infections (STIs). In Australia, explicit negotiation of agreements about sex outside regular relationships has been recommended in health promotion for gay men but not for heterosexuals. Objective: To ascertain the annual incidence of concurrency among people in ongoing male–female relationships according to their reported expectations of exclusivity. Methods: In a national cohort recruited by household random digit dialling in 2004–05, people aged 16–64 years completed computer-assisted telephone interviews including questions about expectations of sexual exclusivity, discussion and agreements. A year later, those in ongoing sexual relationships (5323 people) were asked about sexual partner numbers in the past year. Results: The huge majority (96%) expected sexual exclusivity of themselves and their partner. However, only 48% of men and 64% of women had discussed the matter and explicitly agreed. Older respondents were less likely to report discussion. Only 1% reported mutually nonexclusive (‘open’) relationships. A year later, 93% of respondents were still in the same relationship, among whom 4% of men and 2% of women had had sex outside the relationship. Those with agreements that one or both partners could have sex with others were more likely to do so, but the majority of respondents who had sex with someone else were in relationships that were explicitly or implicitly expected to be exclusive. Conclusions: Sexual health promotion should stress the importance of STI testing and establishing agreements about exclusivity before condoms are abandoned in new relationships.
Coastal acid sulfate soils in the Saloum River basin, Senegal
Authors: Fall Aïdara C. A. Lamine , Montoroi Jean-Pierre , Stahr Karl
Published: October 2014

Soils in boundary conditions of contrasting ecosystems generally show unique features. Transition often leads to changes in soil-forming processes, whereby the environment never comes to equilibrium and therefore the soil chemistry and mineralogy show different influences. Such an environment was analysed in the Saloum River basin, west-central Senegal. The objective was to identify the main pedogenic processes prevailing in this saline and acid pedoenvironment and to assess the influence of environmental factors (climate, topography, soil salinity and acidity) on local soil formation and mineral distribution. The terrace landscape is built up by a floodplain, a low terrace, which is still influenced by groundwater, and a middle terrace. The results show that soil properties are strongly influenced by hydrology, salinity and acidity in the entire toposequence: Gleyic Hyposalic and Hypersalic Solonchaks (Sulfatic) in the floodplain, Haplic Gleysols (Thionic) in the low terrace, and Endogleyic Arenosols in the middle terrace. The oxidation of pyrite followed by the redistribution of the main products (Fe2+ and SO42–) represents the major chemical process responsible for iron oxide and jarosite formation. Mineral distribution and crystallinity are linked to the landscape position, which controls the hydrological behaviour and reactions of Fe and S ions. Finally, we observed intrapedon processes such as gleysation, sulfidisation and sulfurisation, as well as interpedon processes such as salinisation, colluvio-alluviation and lateral eluviation. The combination of processes depends strongly on the landscape positions.
Interactive effects of clay and polyacrylamide properties on flocculation of pure and subsoil clays
Authors: Yan Xiaoqian , Zhang Xunjiang
Published: October 2014

Turbidity reduction is essential for improving surface water quality. Eroded fine sediments not only increase surface water turbidity, they also carry pollutants such as heavy metals and pathogens. The objectives of this study were to investigate the mechanisms of adsorption and desorption of polyacrylamide (PAM) by pure kaolinite and montmorillonite, and to test the ability of PAM to flocculate the two pure clays as well as four subsoils having distinct clay mineralogy. PAMs with different charge type, density, and molecular weights were used, and a standard flocculation series test and an isotherm adsorption method were employed. The results showed that the flocculating power of PAM for the two sodium (Na)-saturated clays followed the order cationic > non-ionic > anionic. Cationic PAM was the most effective flocculent and anionic PAM the least. The magnitude of PAM adsorption by pure clays was strongly affected by PAM charge, clay charge, and clay surface areas. Once adsorbed, desorption was almost impossible. The flocculation series test with natural subsoils showed that all six PAMs with different charge properties and molecular weights were more effective in flocculating the two kaolinitic loam soils than the two smectitic sand soils. The optimal flocculation concentration range was 1–3 mg L–1. The results also indicated that the presence of cation bridges was essential for anionic PAMs to flocculate montmorillonite-dominant soils effectively. The overall results showed that clay–PAM interactions were complex and dynamic, and such complexity necessitates that the optimal flocculation concentration be varied with clay mineralogy and PAM type.
Role of pendant proton relays and proton-coupled electron transfer on the hydrogen evolution reaction by nickel hangman porphyrins
Authors: Bediako D. Kwabena , Solis Brian H. , Dogutan Dilek K. , Roubelakis Manolis M. , Maher Andrew G. , Lee Chang Hoon , Chambers Matthew B. , Hammes-Schiffer Sharon , Nocera Daniel G.
Published: October 2014

Significance

The conversion of solar energy into fuels involves coupled multiproton–multielectron reactions. Because of different length scales for electron transfer and proton transfer, efficient catalysts must couple proton hops to redox events. We have developed a hangman motif where placing a pendant acid–base group over the face of a redox macrocycle ensures coupling of the electron to the proton. We now show that the presence of the pendant acid relay of a Ni hangman porphyrin facilitates proton-coupled electron transfer (PCET) during turnover of the hydrogen evolution reaction (HER). By comparing HER activity of the Ni hangman catalyst to its Co analog, a unified HER mechanism begins to emerge for complexes that use a secondary coordination sphere to manage PCET.
A case for a unified treatment of EFL and ESL
Authors: Deshors Sandra C.
Published: October 2014

This multifactorial corpus-based study focuses on dative alternation constructions (Mark gave his daughter a giftversusMark gave a gift to his daughter) and contrasts 1,313giveoccurrences in ditransitive and prepositional dative constructions across native, learner (EFL) and world (ESL) Englishes. Using cluster analysis and regression modeling, I analyze how grammatical contexts constrain syntactic choices in EFL and ESL and how speakers with different instructional backgrounds develop different variation patterns in their own English variety. The regression model reveals that the English variety factor accounts significantly for syntactic variation. In addition, the study identifies a prototypical prepositional dative construction in non-native English, which serves as a default construction for learners in more complex grammatical contexts. This study stresses the importance of reaching beyond structural linguistic differences by investigating processing (dis)similarities between EFL and ESL and shows the usefulness of a cognitive theoretical framework as a unified approach to cross-varietal variation.
The role of orthography in (apparent) L2 dialect acquisition
Authors: Drummond Rob
Published: October 2014

This paper investigates the role of orthographic representation in the production of the local variant of the STRUT vowel in the speech of Polish migrants living in Manchester. A previous study (Drummond 2013) showed that acquisition of the local variant depended on various social factors, yet this only took into account conversation data, leaving some word list data unexplored. Comparing the two data sets reveals a difference in degree of acquisition, with the word list data producing more of the local vowel. This is explained not as a case of dialect acquisition as such, but more as an effect of orthography triggering a connection to the L1 phonology, the particular nature of which mimics acquisition of the local variant.
Sulfated Bile Acids as Putative Sex Pheromone Components in Pacific Lamprey
Authors: Yun Sang‐Seon , Szeitz Andras , Wildbill Andrew , Siefkes Michael , Close David
Published: October 2014

Pacific Lamprey Entosphenus tridentatus, which is native to the Pacific coast of North America, is an important fisheries resource for some Native American communities and so has been a conservation concern. Chemical analysis of water conditioned with mature male Pacific Lampreys and electrophysiological examination of the identified sulfated bile acids revealed that Pacific Lampreys may use the two bile acid compounds, 3‐keto petromyzonol sulfate (3kPZS) and petromyzonol sulfate (PZS), as mating pheromones that can attract ovulatory females and stimulate them to nest. Liquid chromatography–mass spectrometry analysis on extracts of water conditioned with mature male Pacific Lampreys identified both 3kPZS, known as a major sex pheromone component, and PZS, known as a component of migratory pheromones in Sea Lamprey Petromyzon marinus. When combined with the previous electro‐olfactogram (EOG) data demonstrating olfactory sensitivity of Pacific Lampreys to both compounds, the identification of the two bile acid compounds suggests that Pacific Lamprey evolved to have a chemical communication system for reproduction similar to that of Sea Lamprey. Further studies are required to confirm putative pheromonal functions of these two compounds in Pacific Lamprey. Comprehensive understanding of the reproductive behavior mediated by sex pheromones may provide a helpful tool in restoring the dwindling Pacific Lamprey populations along the North Pacific coast of North America.

Received March 7, 2014; accepted July 10, 2014
Raft and Floating Radio Frequency Identification (RFID) Antenna Systems for Detecting and Estimating Abundance of PIT-tagged Fish in Rivers
Authors: Fetherman Eric R. , Avila Brian W. , Winkelman Dana L.
Published: October 2014

Portable radio frequency identification (RFID) PIT tag antenna systems are increasingly being used in studies examining aquatic animal movement, survival, and habitat use, and their design flexibility permits application in a wide variety of settings. We describe the construction, use, and performance of two portable floating RFID PIT tag antenna systems designed to detect fish that were unavailable for recapture using stationary antennas or electrofishing. A raft antenna system was designed to detect and locate PIT-tagged fish in relatively long (i.e., ≥10 km) river reaches, and consisted of two antennas: (1) a horizontal antenna (4 × 1.2 m) installed on the bottom of the raft and used to detect fish in shallower river reaches (<1 m), and (2) a vertical antenna (2.7 × 1.2 m) for detecting fish in deeper pools (≥1 m). Detection distances of the horizontal antenna were between 0.7 and 1.0 m, and detection probability was 0.32 ± 0.02 (mean ± SE) in a field test using rocks marked with 32-mm PIT tags. Detection probability of PIT-tagged fish in the Cache la Poudre River, Colorado, using the raft antenna system, which covered 21% of the wetted area, was 0.14 ± 0.14. A shore-deployed floating antenna (14.6 × 0.6 m), which covered 100% of the wetted area, was designed for use by two operators for detecting and locating PIT-tagged fish in shorter (i.e., <2 km) river reaches. Detection distances of the shore-deployed floating antenna were between 0.7 and 0.8 m, and detection probabilities during field deployment in the St. Vrain River exceeded 0.52. The shore-deployed floating antenna was also used to estimate abundance of PIT-tagged fish. Results suggest that the shore-deployed floating antenna could be used as an alternative to estimating abundance using traditional sampling methods such as electrofishing.

Received December 19, 2013; accepted July 1, 2014
Real ordinary characters and real Brauer characters
Authors: Tiep Pham
Published: October 2014

We prove that if

G
G

is a finite group and

p
p

is a prime such that the degree of every real-valued irreducible complex, respectively real-valued irreducible

p
p

-Brauer character, of

G
G

is coprime to

p
p

, then

O

p
′

(
G
)

\mathbf {O}^{p’}(G)

is solvable. This result is a generalization of the celebrated Ito–Michler theorem for real ordinary characters, respectively real Brauer characters, with Frobenius-Schur indicator

1
1

.
An astral simulacrum of the central spindle accounts for normal, spindle-less, and anucleate cytokinesis in echinoderm embryos
Authors: Su Kuan-Chung , Bement William M. , Petronczki Mark , von Dassow George
Published: October 2014

Cytokinesis in animal cells depends on spindle-derived spatial cues that culminate in Rho activation, and thereby actomyosin assembly, in a narrow equatorial band. Although the nature, origin, and variety of such cues have long been obscure, one component is certainly the Rho activator Ect2. Here we describe the behavior and function of Ect2 in echinoderm embryos, showing that Ect2 migrates from spindle midzone to astral microtubules in anaphase and that Ect2 shapes the pattern of Rho activation in incipient furrows. Our key finding is that Ect2 and its binding partner Cyk4 accumulate not only at normal furrows, but also at furrows that form in the absence of associated spindle, midzone, or chromosomes. In all these cases, the cell assembles essentially the same cytokinetic signaling ensemble—opposed astral microtubules decorated with Ect2 and Cyk4. We conclude that if multiple signals contribute to furrow induction in echinoderm embryos, they likely converge on the same signaling ensemble on an analogous cytoskeletal scaffold.
Corticosteroid use in neuro-oncology: an update
Authors: Roth Patrick , Happold Caroline , Weller Michael
Published: October 2014

Because of the lack of curative approaches for most patients with malignant brain tumors, supportive therapy, which aims at maintaining quality of life and functional independence, has a central role in the treatment of many patients. Steroids are particularly important in the setting of supportive therapy. They are commonly used to treat tumor-associated edema, and their administration is typically associated with rapid symptom relief, such as the resolution of headaches. Besides their antiedema activity, corticosteroids are characterized by their potent antilymphoma properties and their effects against acute or delayed emesis caused by systemic chemotherapy in cancer patients. Accordingly, steroids are among the most frequently used drugs in oncology. These desirable properties of steroids are counterbalanced by cardiovascular, muscular, and psychiatric side effects. On the cellular level, corticosteroids exert various effects that translate into the desired clinical activity, but they also evoke significant toxicity that may outweigh the beneficial effects. The mode of action and the limitations of steroid treatment are summarized in this review article. Interactions between steroids and other drugs must be considered. A particular challenge to the ongoing use of glucocorticoids is that newer therapeutic approaches are being introduced in neuro-oncology for which concomitant steroids are likely to be contraindicated. These include the emergence of various immunotherapeutic approaches including vaccination strategies and treatment with immune checkpoint inhibitors. Since the administration of steroids may interfere with the activity of these novel therapies, an even more critical evaluation of their use will be required.
A Copula Approach to the Problem of Selection Bias in Models of Government Survival
Authors: Chiba Daina , Martin Lanny W. , Stevenson Randolph T.
Published: October 2014

Theories of coalition politics in parliamentary democracies have suggested that government formation and survival are jointly determined outcomes. An important empirical implication of these theories is that the sample of observed governments analyzed in studies of government survival may be nonrandomly selected from the population of potential governments. This can lead to serious inferential problems. Unfortunately, current empirical models of government survival are unable to account for the possible biases arising from nonrandom selection. In this study, we use a copula-based framework to assess, and correct for, the dependence between the processes of government formation and survival. Our results suggest that existing studies of government survival, by ignoring the selection problem, overstate the substantive importance of several covariates commonly included in empirical models.
Pseudochelatococcus lubricantis gen. nov., sp. nov. and Pseudochelatococcus contaminans sp. nov. from coolant lubricants
Authors: Kämpfer Peter , Glaeser Stefanie P. , Gräber Marco , Rabenstein Andreas , Kuever Jan , Busse Hans-Jürgen
Published: October 2014

Two Gram-negative, rod-shaped, non-spore-forming bacteria, isolated from metal working fluids were investigated to determine their taxonomic positions. On the basis of 16S rRNA gene sequence phylogeny, both strains (MPA 1113T and MPA 1105T) formed a distinct cluster with 97.7 % sequence similarity between them, which was in the vicinity of members of the genera

Methylobacterium

,

Camelimonas

,

Chelatococcus

,

Bosea

,

Salinarimonas

and

Microvirga

to which they showed low sequence similarities (below 94 %). The predominant compounds in the polyamine pattern and in the quinone system of the two strains were spermidine and ubiquinone Q-10, respectively. The polar lipid profiles were composed of the major compounds: phosphatidylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine, major or moderate amounts of diphosphatidylglycerol, two unidentified glycolipids and three unidentified aminolipids. Several minor lipids were also detected. The major fatty acids were either C19 : 0 cyclo ω8c or C18 : 1ω7c. The results of fatty acid analysis and physiological and biochemical tests allowed both, the genotypic and phenotypic differentiation of the isolates from each other, while the chemotaxonomic traits allowed them to be differentiated from the most closely related genera. In summary, low 16S rRNA gene sequence similarities and marked differences in polar lipid profiles, as well as in polyamine patterns, is suggestive of a novel genus for which the name Pseudochelatococcus gen. nov. is proposed. MPA 1113T ( = CCM 8528T = LMG 28286T = CIP 110802T) and MPA 1105T ( = CCM 8527T = LMG 28285T) are proposed to be the type strains representing two novel species within the novel genus, Pseudochelatococcus gen. nov., for which the names Pseudochelatococcus lubricantis sp. nov. and Pseudochelatococcus contaminans sp. nov. are suggested, respectively.
Mesonia aquimarina sp. nov., a marine bacterium isolated from coastal seawater
Authors: Choi Ahyoung , Baek Kiwoon , Lee Hansol , Cho Jang-Cheon
Published: October 2014

A Gram-staining-negative, aerobic, yellow, non-flagellated, non-gliding, rod-shaped bacterium, designated strain IMCC1021T, was isolated off the coast of the East Sea. Optimal growth of strain IMCC1021T was observed at 25 °C, pH 7.0–7.5 and in the presence of 3.0–3.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain belonged to the genus

Mesonia

, showing a close relationship with

Mesonia mobilis

KMM 6059T (97.4 % similarity) followed by

Mesonia phycicola

MDSW-25T (96.1 %). DNA–DNA relatedness between strain IMCC1021T and

M. mobilis

KMM 6059T was 17.5 % (reciprocal 7.4 %), which indicated that the new isolate represents a novel genomic species of the genus

Mesonia

. The major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH, and the G+C content of the genomic DNA was 41.4 mol%. Strain IMCC1021T contained menaquinone-6 (MK-6) as the respiratory quinone, and polar lipids comprising phosphatidylethanolamine, two unknown aminolipids and three unknown polar lipids. On the basis of the phylogenetic distinctions and differential phenotypic characteristics, it is suggested that strain IMCC1021T ( = KCTC 32320T = NBRC 109485T) should be assigned to the genus

Mesonia

as the type strain of a novel species, for which the name Mesonia aquimarina sp. nov. is proposed.
Reconstitution of CPSF active in polyadenylation: recognition of the polyadenylation signal by WDR33
Authors: Schönemann Lars , Kühn Uwe , Martin Georges , Schäfer Peter , Gruber Andreas R. , Keller Walter , Zavolan Mihaela , Wahle Elmar
Published: October 2014

Cleavage and polyadenylation specificity factor (CPSF) is the central component of the 3′ processing machinery for polyadenylated mRNAs in metazoans: CPSF recognizes the polyadenylation signal AAUAAA, providing sequence specificity in both pre-mRNA cleavage and polyadenylation, and catalyzes pre-mRNA cleavage. Here we show that of the seven polypeptides that have been proposed to constitute CPSF, only four (CPSF160, CPSF30, hFip1, and WDR33) are necessary and sufficient to reconstitute a CPSF subcomplex active in AAUAAA-dependent polyadenylation, whereas CPSF100, CPSF73, and symplekin are dispensable. WDR33 is required for binding of reconstituted CPSF to AAUAAA-containing RNA and can be specifically UV cross-linked to such RNAs, as can CPSF30. Transcriptome-wide identification of WDR33 targets by photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation (PAR-CLIP) showed that WDR33 binds in and very close to the AAUAAA signal in vivo with high specificity. Thus, our data indicate that the large CPSF subunit participating in recognition of the polyadenylation signal is WDR33 and not CPSF160, as suggested by previous studies.
Application of histone modification-specific interaction domains as an alternative to antibodies
Authors: Kungulovski Goran , Kycia Ina , Tamas Raluca , Jurkowska Renata Z. , Kudithipudi Srikanth , Henry Chisato , Reinhardt Richard , Labhart Paul , Jeltsch Albert
Published: October 2014

Post-translational modifications (PTMs) of histones constitute a major chromatin indexing mechanism, and their proper characterization is of highest biological importance. So far, PTM-specific antibodies have been the standard reagent for studying histone PTMs despite caveats such as lot-to-lot variability of specificity and binding affinity. Herein, we successfully employed naturally occurring and engineered histone modification interacting domains for detection and identification of histone PTMs and ChIP-like enrichment of different types of chromatin. Our results demonstrate that histone interacting domains are robust and highly specific reagents that can replace or complement histone modification antibodies. These domains can be produced recombinantly inEscherichia coliat low cost and constant quality. Protein design of reading domains allows for generation of novel specificities, addition of affinity tags, and preparation of PTM binding pocket variants as matching negative controls, which is not possible with antibodies.
Crystal structure of bis{2-[bis(2-hydroxyethyl)amino]ethanol-κ3O,N,O′}zinc terephthalate
Authors: Li Ya-Ping , Zang Hu , Sun Dajun , Ming Julia , Su Guan-Fang
Published: October 2014

In the title salt, [Zn(C6H15NO3)2](C8H4O4), the ZnIIcation, located on a centre of inversion, is coordinated by four O atoms and two N atoms from two tridentate 2-[bis(2-hydroxyethyl)amino]ethanol (BHEA) ligands, giving rise to a slightly distorted octahedral geometry. The terephthalate dianion, located about a centre of inversion, is not coordinated to ZnIIbut is connected through O—H...O contacts with [Zn(BHEA)2]2+cations, leading to a three-dimensional crystal structure.
Crystal structure of 4-amino-5-fluoro-2-oxo-2,3-dihydropyrimidin-1-ium 3-hydroxypyridine-2-carboxylate
Authors: Karthikeyan Ammasai , Thomas Muthiah Packianathan , Perdih Franc
Published: October 2014

The asymmetric unit of the title salt, C4H5FN3O+·C6H4NO3−, contains one 4-amino-5-fluoro-2-oxo-2,3-dihydropyrimidin-1-ium (5-fluorocytosinium, 5FC) cation and a 3-hydroxypicolinate (3HAP) anion. The 4-amino-5-fluoro-2-oxo-2,3-dihydropyrimidine molecule is protonated at one of the pyrimidine N atoms. The typical intramolecular N—H...F and O—H...OS(5) andS(6) hydrogen-bond ring motifs are observed in the cations and anions. The protonated N atom and 2-amine group of the 5FC cation interact with the 3HPA anion through a pair of nearly parallel N—H...O hydrogen bonds, forming a robustR22(8) ring motif. The ions are further linked by N—H...N, O—H...O, N—H...O and C—H...O hydrogen bonds, generatingR22(7),R33(12) andR65(18) ring motifs, respectively, leading to supramolecular wave-like sheets parallel to (010). The crystal structure is further stabilized by C—H...π interactions, generating a three-dimensional architecture.
Crystal structure ofN-(quinolin-6-yl)hydroxylamine
Authors: Rajapakse Anuruddha , Hillebrand Roman , Lewis Sarah M. , Parsons Zachary D. , Barnes Charles L. , Gates Kent S.
Published: October 2014

The title compound, C9H8N2O, crystallized with four independent molecules in the asymmetric unit. The four molecules are linkedviaone O—H...N and two N—H...N hydrogen bonds, forming a tetramer-like unit. In the crystal, molecules are further linked by O—H...N and N—H...O hydrogen bonds forming layers parallel to (001). These layers are linkedviaC—H...O hydrogen bonds and a number of weak C—H...π interactions, forming a three-dimensional structure. The crystal was refined as a non-merohedral twin with a minor twin component of 0.319.
Crystal structure oftert-butyl-N-phenylcarbonitrilium tetrachloridoaluminate
Authors: Dijk Tom van , Zant Dirk W. , Wolf Robert , Lammertsma Koop , Slootweg J. Chris
Published: October 2014

In the title compound, (C11H14N)[AlCl4], the nitrilium (systematic name: 2,2-dimethyl-N-phenylpropanenitrilium) ion adopts a slightly distorted linear configuration [C—N[triple-bond]C = 178.87 (16) and N[triple-bond]C—C = 179.13 (17)°]. In the crystal, while there are no intermolecular hydrogen bonds, pairs of nitrilium ions are linked through π–π interactions [inter–centroid distance = 3.8091 (13) Å].
Crystal structure of dichlorido{2-[(2-hydroxyethyl)(pyridin-2-ylmethyl)amino]ethanolato-κ4N,N′,O,O′}iron(III) dihydrate from synchrotron data
Authors: Shin Jong Won , Kim Dae-Woong , Moon Dohyun
Published: October 2014

In the title compound, [Fe(C10H15N2O2)Cl2]·2H2O, the FeIIIion is coordinated by two N and two O atoms of the tetradentate 2-{(2-hydroxyethyl)(pyridin-2-ylmethyl)amino}ethanolate ligand and by two chloride anions, resulting in a distorted octahedral coordination sphere. The average Fe—X(X= ligand N and O atoms) and Fe—Cl bond lengths are 2.10 and 2.32 Å, respectively. In the crystal, duplex O—H...O hydrogen bonds between the hydroxyl and ethoxy groups of two neighbouring complexes give rise to a dimeric unit. The dimers are connected to the lattice water molecules (one of which is equally disordered over two sets of sites) through O—H...Cl hydrogen bonds, forming undulating sheets parallel to (010). Weak C—H...Cl hydrogen bonds are also observed.
Viruses and viral proteins
Authors: Verdaguer Nuria , Ferrero Diego , Murthy Mathur R. N.
Published: October 2014

For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes.
Coordination preferences of the alkali cations sodium and caesium in the mixed-cationic Zintl ammoniate Cs3.2Na0.8Ge9·5.3NH3
Authors: Gärtner Stefanie , Suchentrunk Christof , Korber Nikolaus
Published: October 2014

The involvement of two different alkali cations in the nonagermanide ammoniate Cs3.2Na0.8Ge9·5.3NH3[tricaesium sodium nonagermanide–ammonia (1/5.3)] provides insights into the coordination behaviour of ammonia towards sodium and caesium cations within one compound and represents the first mixed-cationic solvate structure of nonagermanide tetraanions. The compound crystallizes in the monoclinic space groupP21/mand, with the presence of pseudomerohedral twinning, mixed-cation sites and disordering of the nonagermanide cage anions, features a combination of crystallographic challenges which could all be resolved during the refinement.
Placement of DG for reliability improvement and loss minimization with reconfiguration of radial distribution systems
Authors: Pavani Ponnaganti , Singh S.N.
Published: October 2014

Purpose

– The purpose of the paper is to find the best distributed generators (DGs) location for improving reliability and reducing power loss using distribution system reconfiguration. This is implemented in the presence of the tie-switches. It proposes a search-based algorithm for the reconfiguration problem. Individual DG placement is obtained for all system configurations, and analytical hierarchy process tool is used for finding the overall best location. This is carried out for various system loadings.

Design/methodology/approach

– This paper proposes a knowledge-based search algorithm which needs the base conditions of the distribution system. A detailed analysis is carried out for finding the best DG locations from the obtained DG placements for various system configurations. Simulations are rigorously carried out with the help of programming. Results from these simulations are further given to analytical hierarchy tool for obtaining the DGs location.

Findings

– The findings of the paper are the DG placement for various system loadings and various system configurations and to obtain the best DG location for any system configuration. A search-based algorithm is designed for accomplishing it.

Originality/value

– The proposed method identifies the placement of distributed generation at distribution systems for reliability improvement and power loss reduction which is one of the present day needs for fulfilling the raising power consumers.
Organizational transformation and higher sustainability management education
Authors: Lee Ki-Hoon , Schaltegger Stefan
Published: October 2014

Purpose

– This paper aims to investigate the roles of leadership in enabling sustainability transformation of universities and higher sustainability management education. It advocates research into the role of leadership for a university’s sustainability transformation by exploring interactions between university members and institutional contexts.

Design/methodology/approach

– Using a case study approach, this study explores the sustainability transformation of a university and its influence on the MBA Sustainability Management by applying Mintzberg’s leadership framework.

Findings

– The findings suggest that leaders can strongly influence a process of change in mindsets, practices and curricula to incorporate sustainability into higher business education institutions. Whereas bottom-up leadership initiatives are crucial, leadership support from top management is seen as important to enable larger, more radical steps of transformation.

Originality/value

– It is worthy noting that in the medium run strategic leadership to develop good sustainability management education programs requires a consistent institutional commitment for sustainability.
The newly created Publicly Available Specification (PAS 141) for reusable electrical/electronic products
Authors: Quariguasi-Frota-Neto Joao , Reade Andrew , Dindarian Azadeh , Gibson Andrew
Published: October 2014

Purpose

– In 2011, a governmental initiative driven by the Department for Business Innovation and Skills invited the British Standards Institute (BSI) to write and publish a publicly available specification (PAS) for the reuse of waste electrical and electronic equipment entitled PAS 141. The specification's ambitious goals, chief among them to reduce the amount of e-waste generated in the UK, has prompted debate as to whether they are realistic and the extent to which they can be influenced by the certification. The purpose of this paper is to propose a comprehensive framework that can be used in future research to enhance understanding of the mechanisms by which the introduction of PAS 141 certification could lead to the fulfillment of its goals, that is, successful uptake. The authors believe this framework can serve as a roadmap for those interested in the investigation of this novel certification and its effect on the market for reusable electrical and electronic products.

Design/methodology/approach

– This paper is based on interviews with reuse organizations and first hand experience as a participant in the steering group that elaborated the certification being investigated, i.e. PAS 141.

Findings

– It is uncertain whether PAS 141 will fulfill its promises, which are, in the view of the authors, rather ambitious, e.g. reduce e-waste. Furthermore, more research is needed to examine the effect that the introduction of the certification has on the materialization of its goals, and on the complex inter-relationship that exist between the goals and what the authors define as intermediary necessary conditions.

Research limitations/implications

– This is the first attempt the outline the research needs that arise from the introduction of PAS-141, and the authors believe that there are other equally important questions that are yet to be presented and examined.

Practical implications

– This paper proposes 28 hypotheses which will help future work to empirically establish: the possibility of PAS-141 attaining its goals and the main necessary conditions for that to happen. This information is pivotal to determine whether the certification is working and to pinpoint opportunities for improvement.

Social implications

– This works contributes to the understanding of the role of certification on the market of reused products, which employs a large number of people, and in particular, whose coming from disadvantaged backgrounds.

Originality/value

– Although certification in general has been widely investigated in prior research, scant attention has been paid to certification in the context of electronic products. To the best of the knowledge, this is the first paper of its kind, as it is the first to examine certification in that context.
Hydrological niches in terrestrial plant communities: a review
Authors: Silvertown Jonathan , Araya Yoseph , Gowing David
Published: October 2014

Despite the fundamental significance of water to plants and the persisting question of how competing species coexist, this is the first review of hydrological niches. We define hydrological niche segregation (HNS) as: (i) partitioning of space on fine‐scale soil‐moisture gradients, (ii) partitioning of water as a resource and/or (iii) partitioning of recruitment opportunities among years caused by species specializing on particular patterns of temporal variance of water supply (the storage effect).

We propose that there are three types of constraint that lead to the trade‐offs that underlie HNS. (i) An edaphic constraint creates a trade‐off between the supply to roots of O2 on the one hand vs. water and nutrients on the other. (ii) A biophysical constraint governs gas exchange by leaves, leading to a trade‐off between CO2 acquisition vs. water loss. (iii) A structural constraint arising from the physics of water‐conducting tissues leads to a safety vs. efficiency trade‐off.

Significant HNS was found in 43 of 48 field studies across vegetation types ranging from arid to wet, though its role in coexistence remains to be proven in most cases. Temporal partitioning promotes coexistence through the storage effect in arid plant communities, but has yet to be shown elsewhere. In only a few cases is it possible to unequivocally link HNS to a particular trade‐off.

Synthesis. The field and experimental evidence make it clear that HNS is widespread, though it is less clear what its precise mechanisms or consequences are. HNS mechanisms should be revealed by further study of the constraints and trade‐offs that govern how plants obtain and use water, and HNS can be mechanistically linked to its consequences with appropriate community models. In a changing climate, such an integrated programme would pay dividends for global change research.
A phasin with extra talents: a polyhydroxyalkanoate granule‐associated protein has chaperone activity
Authors: Mezzina Mariela P. , Wetzler Diana E. , de Almeida Alejandra , Dinjaski Nina , Prieto M. Auxiliadora , Pettinari Maria Julia
Published: October 2014

Phasins are proteins associated to intracellular polyhydroxyalkanoate granules that affect polymer accumulation and the number and size of the granules. Previous work demonstrated that a phasin from Azotobacter sp FA‐8 (PhaPAz) had an unexpected growth‐promoting and stress‐protecting effect in Escherichia coli, suggesting it could have chaperone‐like activities. In this work, in vitro and in vivo experiments were performed in order to investigate this possibility. PhaPAz was shown to prevent in vitro thermal aggregation of the model protein citrate synthase and to facilitate the refolding process of this enzyme after chemical denaturation. Microscopy techniques were used to analyse the subcellular localization of PhaPAz in E. coli strains and to study the role of PhaPAz in in vivo protein folding and aggregation. PhaPAz was shown to colocalize with inclusion bodies of PD, a protein that aggregates when overexpressed. A reduction in the number of inclusion bodies of PD was observed when it was coexpressed with PhaPAz or with the known chaperone GroELS. These results demonstrate that PhaPAz has chaperone‐like functions both in vitro and in vivo in E. coli recombinants, and suggests that phasins could have a general protective role in natural polyhydroxyalkanoate producers.
Does Information about Sugar Source Influence Consumer Liking of Products Made with Beet and Cane Sugars?
Authors: Urbanus Brittany L. , Schmidt Shelly J. , Lee Soo‐Yeun
Published: October 2014

Beet sugar contains an off‐aroma, which was hypothesized to generate expectations on the acceptability of a product made with beet sugar. Thus, the objective of this study was to assess the impact of information about the sugar source (beet vs. cane) on the overall liking of an orange‐flavored beverage. One hundred panelists evaluated an orange‐flavored powdered beverage mix and beverage made with beet and cane sugars using a 5‐phase testing protocol involving a tetrad test and hedonic ratings performed under blind and informed conditions. Tetrad test results indicated that there was a significant difference (P < 0.05) between the beverage mix made with beet sugar and cane sugar; however, no difference was found between the beverage made with beet sugar and cane sugar. Hedonic ratings revealed the significance of information conditions on the panelists evaluation of sugar (F = 24.67, P < 0.001); however, no difference in the liking was identified for the beverage mix or beverage. Average hedonic scores were higher under informed condition compared to blind condition for all products, possibly because labels tend to reduce uncertainty about a product. Results from this study are representative of the responses from the general population and suggest that they are not affected by sugar source information in a beverage product. Based on concerns with the use of beet sugar expressed in the popular press, there may be a subgroup of the population that has a preconceived bias about sugar sources due to their prior experiences and knowledge and, thus, would be influenced by labels indicating the sugar source used in a product.
Evaluation of Texture Differences among Varieties of Cooked Quinoa
Authors: Wu Geyang , Morris Craig F. , Murphy Kevin M.
Published: October 2014

Texture differences of cooked quinoa were studied among 13 different varieties. Correlations between the texture parameters and seed composition, seed characteristics, cooking quality, flour pasting properties, and flour thermal properties were determined. The results showed that texture of cooked quinoa was significantly differed among varieties. ‘Black,’ ‘Cahuil,’ and ‘Red Commercial’ yielded harder texture, while ‘49ALC,’ ‘1ESP,’ and ‘Col.#6197’ showed softer texture. ‘49ALC,’ ‘1ESP,’ ‘Col.#6197,’ and ‘QQ63’ were more adhesive, while other varieties were not sticky. The texture profile correlated to physical‑‐chemical properties in different ways. Protein content was positively correlated with all the texture profile analysis (TPA) parameters. Seed hardness was positively correlated with TPA hardness, gumminess, and chewiness at P ≤ 0.09. Seed density was negatively correlated with TPA hardness, cohesiveness, gumminess, and chewiness, whereas seed coat proportion was positively correlated with these TPA parameters. Increased cooking time of quinoa was correlated with increased hardness, cohesiveness, gumminess, and chewiness. The water uptake ratio was inversely related to TPA hardness, gumminess, and chewiness. Rapid Visco Analyzer peak viscosity was negatively correlated with the hardness, gumminess, and chewiness (P < 0.07); breakdown was also negatively correlated with those TPA parameters (P < 0.09); final viscosity and setback were negatively correlated with the hardness, cohesiveness, gumminess, and chewiness (P < 0.05); setback was correlated with the adhesiveness as well (r = −0.63, P = 0.02). Onset gelatinization temperature (To) was significantly positively correlated with all the texture profile parameters, and peak temperature (Tp) was moderately correlated with cohesiveness, whereas neither conclusion temperature (Tc) nor enthalpy correlated with the texture of cooked quinoa.