bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of chromosomal mediated cadmium resistance in Pseudomonas aeruginosa strain BC15
Authors: Raja Chellaiah Edward , Selvam Govindan Sadasivam 
Published: October 2011

AbstractCadmium (Cd) has been used extensively in metal plating, mining, paints and plastic generation etc. In this study, Cd resistance (cadR) gene was characterized from the environmental isolate Pseudomonas aeruginosa BC15. The cadR sequences showed high homology with P. aeruginosa FLH033011 (100%), P. aeruginosa PAO1 (99%), and P. aeruginosa UCBPP‐PA14 (98%) respectively. Homology modeling of cadR was carried out by using swiss‐prot server. Crystal structures of E. coli CueR for Cu (1q05) and ZntR (1q08) for Zn have been used as a template. The sequence identity of P. aeruginosa cadR shares 34% for CueR and 43% for ZntR. Fold recognition of P. aeruginosa cadR was created by using PHYRE web server. Transcriptional regulator CueR (1q06a) from E. coli was chosen as the template. CadR has 31% identity and the estimated precision was 100%. The cadR gene was cloned in pET30b and transformed into E. coli BL21. The molecular weight protein of cadR was estimated to be 25 kDa by SDS‐PAGE. The recombinant E. coli cadR efficiently grow in the Cd supplemented LB medium and agar plate. The order of the resistance of E. coli cadR was Mn > Pb > Cu > Cd > Ni > Zn. These findings can lead to the use of P. aeruginosa BC15 for the remediation of Cd and other heavy metals present in the polluted environment. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation and characterization of heavy‐metal resistant microbes from roadside soil and phylloplane
Authors: Mohamed Rehab M. , Abo‐Amer Aly E. 
Published: October 2011

AbstractContamination by heavy metals is one of the major environmental problems in many countries and these contaminants reach from various sources such as traffic cars and other activities. Soil and phylloplane samples were collected from eight traffic and two non‐traffic sites in Sohag city, Egypt. Heavy metal contents of Cd2+, Zn2+ and Pb2+ of soil and phylloplane samples were determined and revealed high levels of Zn2+ and Pb2+ in traffic samples. A total of 112 bacterial and 62 fungal isolates were obtained from soil and phylloplane. Bacterial isolates were characterized on the basis of morphological, physicochemical and biochemical characteristics; and 16S rRNA gene sequences. Fungal isolates were identified according to morphological characterization. Minimal inhibitory concentrations (MICs) of Cd2+, Zn2+ and Pb2+ for each isolate were detected. All bacterial and fungal isolates demonstrated resistance to lead with MICs >0.528 mM and >0.211, respectively. Moreover, the maximum MICs of cadmium and zinc for bacteria were 0.821 mM and 1.471 mM, respectively, where as, MICs for fungi were 0.328 mM and 0.588 mM, respectively. The most resistant bacterial and fungal isolates were Pseudomonas aeruginosa RA65 and Penicillium corylophyllum, respectively. Therefore, P. aeruginosa RA65 was selected for further investigations. Growth curve study showed that 0.264 mM lead had no efficiently effect on the growth of P. aeruginosa RA65. Plasmid isolation evidenced by transformation studies indicated that P. aeruginosa RA65 harbored a single plasmid (∼9.5 kb) which mediated heavy meal resistance. Consequently, these microbial isolates could be potentially used in bioremediation of heavy metal‐contaminated environment. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and properties of poly(butylene succinate): Efficiency of different transesterification catalysts
Authors: Jacquel Nicolas , Freyermouth Floriane , Fenouillot Françoise , Rousseau Alain , Pascault Jean Pierre , Fuertes Patrick , Saint‐Loup René 
Published: October 2011

AbstractThe efficiency of organometal‐ (Ti, Zr, Sn, Hf, and Bi) and metal oxide‐ (Ge and Sb) based catalysts was investigated during the transesterification step of the synthesis of poly(butylene succinate) (PBS). PBS was prepared from succinic acid and 1,4‐butanediol via a two‐stage melt polycondensation process. The catalytic efficiency of the organometal catalysts was as follows: Ti≫Zr∼ Sn>Hf>Sb>Bi. The germanium and antimony metal oxides displayed desirable catalytic efficiency when were associated with hydroxy acids (lactic acid or glycolic acid), which acted as chelating agents. However, this catalytic system exhibited lower efficiency compared to the titanium system. Furthermore, at high concentrations of hydroxy acids the overall transesterification rate decreased. This effect can be explained by the substitution of PBS hydroxyl end groups by a lactic or glycolic unit, both of which are less reactive during the transesterification reaction. The role of catalytic residues during the storage and processing of PBS was also studied. The reduced viscosity of the PBS samples did not vary when processing at 190 °C from 1 to 10 minutes. However, when stored under ambient conditions, all PBS samples were prone to significant hydrolytic degradation, especially those containing a titanium catalyst. This behavior indicates that zirconium‐ and germanium‐based catalysts could be interesting substitutes for titanium‐based catalysts. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.
End‐group fidelity of copper(0)‐meditated radical polymerization at high monomer conversion: an ESI‐MS investigation
Authors: Nyström Fredrik , Soeriyadi Alexander H. , Boyer Cyrille , Zetterlund Per B. , Whittaker Michael R. 
Published: October 2011

AbstractCopper(0)‐mediated radical polymerization (single electron transfer‐living radical polymerization) is an efficient polymerization technique that allows control over the polymerization of acrylates, vinyl chloride and other monomers, yielding bromide terminated polymer. In this contribution, we investigate the evolution of the end‐group fidelity at very high conversion both in the presence and in the absence of initially added copper (II) bromide (CuBr2). High resolution electrospray‐ionization mass spectroscopy (ESI‐MS) allows determination of the precise chemical structure of the dead polymers formed during the polymerization to very high monomer conversion, including post polymerization conditions. Two different regimes can be identified via ESI‐MS analysis. During the polymerization, dead polymer results mainly from termination via disproportionation, whereas at very high conversion (or in the absence of monomer, that is, post‐polymerization), dead polymers are predominantly generated by chain transfer reactions (presumably to ligand). The addition of CuBr2 significantly reduces the extent of termination by both chain transfer and disproportionation, at very high monomer conversion and under post‐polymerization conditions, offering a convenient approach to maintaining high end‐group fidelity in Cu(0)‐mediated radical polymerization. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis of porphyrin‐end‐functionalized polycyclohexane with well‐controlled and defined polymer chain structure
Authors: Natori Itaru , Natori Shizue , Kanasashi Anna , Tsuchiya Kosuke , Ogino Kenji 
Published: October 2011

AbstractTetraphenylporphyrin‐end‐functionalized polycyclohexane (H2TPP‐PCHE) and its metal complexes (MTPP‐PCHE) were synthesized as the first successful example of porphyrin‐end‐functionalized transparent and stable polymers with a well‐controlled and defined polymer chain structure. Chloromethyl‐end‐functionalized poly(1,3‐cyclohexadiene) (CM‐PCHD) was synthesized as prerequisite prepolymer by the postpolymerization reaction of poly(1,3‐cyclohexadienyl)lithium and chloro(chloromethyl)dimethylsilane. CM‐end‐functionalized PCHE (CM‐PCHE) was prepared by the complete hydrogenation of CM‐PCHD with p‐toluenesulfonyl hydrazide. H2TPP was incorporated onto the polymer chain end by the addition of 5‐(4‐hydroxyphenyl)‐10,15,20‐triphenylporphyrin to CM‐PCHE. The complexation of H2TPP‐PCHE and Zn(OAc)2 (or PtCl2) yielded a zinc (or platinum) complex of H2TPP‐PCHE. H2TPP‐PCHE and MTPP‐PCHE were readily soluble in common organic solvents, and PCHE did not inhibit the optical properties of the H2TPP, ZnTPP, and PtTPP end groups. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Probing the effects of π–π stacking on the controlled radical polymerization of styrene and fluorinated styrene
Authors: Pickett Phillip D. , Radzinski Scott C. , Tillman Eric S. 
Published: October 2011

AbstractThe addition of the π–π stacking agent octafluorotoluene (OFT) resulted in up to a 50% reduction in monomer conversion after 24 h for atom transfer radical polymerization (ATRP) reactions of styrene, when performed at 85 °C with 1 eq of OFT compared with styrene in the initial reaction mixture. Monitoring the progress showed that the ATRP of styrene in the presence of either OFT or hexafluorobenzene (HFB) maintained a linear relationship between monomer conversion and number average molecular weights, while showing a first order rate dependence on monomer. The effects of π–π stacking on the KATRP could be overcome by using adjusting the redox activity of the metal‐ligand complex while maintaining reaction temperatures of 85 °C. Further experiments showed that nitroxide‐mediated polymerizations of St were affected to an identical extent by the presence of the π–π stacking agent HFB. The ATRP of pentafluorostyrene (PFSt) in the presence of π–π stackers benzene or toluene showed an increase in monomer conversion compared with reactions in their absence, consistent with Mn π–π stacking increasing the stability of the active radical. Interactions between the π–π stacking agents OFT and HFB and the aromatic groups in the ATRP of St or PFSt were verified by 1H NMR analysis. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
The effects of a HfO2 buffer layer on Al2O3‐passivated indium‐gallium‐zinc‐oxide thin film transistors
Authors: Ko Youngbin , Bang Seokhwan , Lee Seungjun , Park Soyeon , Park Joohyun , Jeon Hyeongtag 
Published: October 2011

AbstractIn this study, the effects of a HfO2 buffer layer between an Al2O3 passivation layer and an indium‐gallium‐zinc‐oxide (IGZO) thin film transistor (TFT) were investigated to enhance the environmental stability and electrical properties of the IGZO TFT. When applying the HfO2 buffer layer, the formation of HfAlx Oy at the Al2O3/HfO2 interface reduces the water vapor transmission rate (WVTR) due to densification of the passivation layer. Consequently, by adding the HfO2 buffer layer, WVTR of the TFT was highly improved; moreover, changes in the electrical characteristics can be prevented compared to both the non‐passivated and Al2O3‐passivated TFTs. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improving the image of delicate and complex biological surfaces
Authors: Rosowski J‐ R. , Hoagland K. D. , Roemer S. C. , Lee K. W. 
Published: October 2011

AbstractAn initial thermal evaporative coating with Au/Pd protects delicate biological surfaces from thermal damage caused by diode sputtering, allowing additional coating if necessary by the quicker and more complete sputtering method. Additional coating by either method (1) reduces charging and bright areas, (2) improves the physical stability of entire samples and of delicate cell features, and (3) may provide sharper images at high magnification by reducing subtle specimen drift. Most consistent elimination of charging occurred when 10 nm or more of Au/Pd was sputtered on specimens showing charging when previously coated with 30 nm of Au/Pd by thermal evaporation. Aquatic microcommunities, particularly those laden with silt, were characterized by extensive interstitial space so that adequate electrical conductivity required several additional sputter coatings.
A simple method for making composite anaglyph transparencies for viewing from a single light source
Authors: Pardoe D. L. 
Published: October 2011

AbstractThis paper presents an easy technique that enables one to make composite anaglyph transparencies in any size up to 11 × 14 inches from SEM or TEM negatives. For viewing with an overhead projector, right and left images are printed on separate, fine‐grain positive films, usually 5 × 7 to 8 × 10 inches in size. Standard black and white printing techniques are used throughout. The red and green stereo code is added to the two photographic emulsions with chemical toners. The transparencies are then superimposed, aligned, and presented using an overhead projector. As with other anaglyph processes, red and green spectacles are used for viewing.
A fragment‐based retransmission scheme with quality‐of‐service considerations for wireless networks
Authors: Kuo Chin‐Fu , Tseng Hsueh‐Wen , Pang Ai‐Chun 
Published: October 2011

ABSTRACTIn order to satisfy quality‐of‐service requirements for real‐time multimedia applications over wireless networks, IEEE 802.11e has been proposed to enhance wireless‐access functionalities. In IEEE 802.11e, collisions occur frequently as the system load becomes heavy, and then, the latency for successfully transmitting data is lengthened seriously because of contention, handshaking, and backoff overheads for collision avoidance. In this paper, we propose a fragment‐based retransmission (FBR) scheme with quality‐of‐service considerations for IEEE 802.11e‐based wireless local area networks. Our FBR can be used in all proposed fragmentation‐based schemes and greatly decrease redundant transmission overheads. By utilizing FBR, the retransmission delay will be significantly improved to conform strict time requirements for real‐time multimedia applications. We develop an analytical model and a simulation model to investigate the performance of FBR. The capability of the proposed scheme is evaluated by a series of simulations, for which we have encouraging results. Copyright © 2011 John Wiley & Sons, Ltd.
An efficient anonymous communication protocol for wireless sensor networks
Authors: Chen Juan , Du Xiaojiang , Fang Binxing 
Published: October 2011

ABSTRACTAnonymous communication is very important for many wireless sensor networks, because it can be used to hide the identity of important nodes, such as the base station and a source node. In sensor networks, anonymous communication includes several important aspects, such as source anonymity, communication relationship anonymity, and base station anonymity. Existing sensor network anonymous schemes either cannot achieve all the anonymities or have large computation, storage, and communication overheads. In this paper, we propose an efficient anonymous communication protocol for sensor networks that can achieve all the anonymities while having small overheads on computation, storage, and communication. We compare our anonymous communication protocol with several existing schemes, and the results show that our protocol provides strong anonymity protection and has low overheads. Copyright © 2011 John Wiley & Sons, Ltd.
Ionic Radii and Ionic Volumes, Models in Mutual Comparison Illustrated with Some Examples
Authors: Bronger Welf 
Published: October 2011

AbstractThe comparison of different concepts to approximate ionic radii and volumes (V.M. Goldschmidt, L. Pauling, R.D. Shannon, W. Biltz) reveal their usefulness although they are knowingly based on simple models. Nevertheless, calculations of atomic and ionic volumina based on the Quantum Theory of Atoms in Molecules (QTAIM) developed by Bader will prospectively afford deeper insights into bonding situations of compounds from the field of inorganic solid state chemistry.
Do waveless ships exist? Results for single-cornered hulls
Authors: Trinh Philippe H. , Chapman S. Jonathan , Vanden-Broeck Jean-Marc 
Published: October 2011

AbstractConsider low-speed potential flow past a ship modelled as a semi-infinite two-dimensional body with constant draught. Is it possible to design the hull in such a way as to eliminate the waves produced downstream of the ship? In 1977, Vanden-Broeck & Tuck had conjectured that a single-cornered piecewise-linear hull will always generate a wake; in this paper, we show how recently developed tools in exponential asymptotics can be used to confirm this conjecture. In particular, we show how the formation of waves near a ship is a necessary consequence of singularities in the ship’s geometry (or its analytic continuation). Comprehensive numerical computations confirm the analytical predictions.
The graptolite, conodont and sedimentary record through the late Ludlow Kozlowskii Event (Silurian) in the shale-dominated succession of Bohemia
Authors: MANDA ŠTĚPÁN , ŠTORCH PETR , SLAVÍK LADISLAV , FRÝDA JIŘÍ , KŘÍŽ JIŘÍ , TASÁRYOVÁ ZUZANA 
Published: October 2011

AbstractThe shale-dominated hemipelagic succession exposed in the southwestern part of the Prague Synform preserves the most complete Ludfordian graptolite record so far encountered from peri-Gondwanan Europe. Four graptolite biozones – theNeocucullograptus inexpectatus,Nc. kozlowskii,Pseudomonoclimacis latilobus–Slovinograptus balticusandPristiograptus fragmentalisbiozones – are recognized in the middle and late Ludfordian, between theBohemograptus tenuisBiozone and the base of the Pridoli Series. Conodont occurrences are restricted to scattered limestone beds, but enable tentative integration of the graptolite and conodont biozonal schemes. Particular attention was paid to faunal and sedimentary changes and the carbon isotope record across the middle Ludfordian Kozlowskii extinction Event. The Kozlowskii Event caused the almost simultaneous extinction of graptolites with ventrally curved rhabdosomes. The generaBohemograptus,PolonograptusandNeocucullograptus, along withPseudomonoclimacis dalejensis, disappeared from the fossil record. The offshore conodont fauna recorded in the section was not strongly affected and similarly the pelagic orthocerids and nektonicCeratiocarispassed unaffected through the extinction interval. The abundant and widespread pelagic myodocopid ostracodEntomis, however, became extinct. The late Ludfordian graptolite recovery gave origin to a novel fauna of Pridoli type from taxa that emerged or just reappeared above the Kozlowskii crisis. In Všeradice and elsewhere in the Prague Synform, the recovery, manifested by the appearance ofPseudomonoclimacis latilobusandSlovinograptus balticus, closely postdates the end of the isotope excursion but pre-dates the first appearance of the conodont index ‘Ozarkodina’snajdri. Here the graptolite recovery was delayed relative to the recovery of the benthic fauna. A canalized intraformational limestone conglomerate corresponds with a gap in the sedimentary record above the Kozlowskii extinction and just below the graptolite recovery. The benthic faunas from the conglomerate matrix and pebbles permit correlation with the shallower part of the basin indicating a distinct fall in sea-level. The present data demonstrate the coincidence of the graptolite crisis with benthic faunal change and eustatic fall in sea-level manifested by facies change and the carbon isotope excursion.Polonograptus chlupacisp. nov., from theNc. kozlowskiiBiozone, is described and several other graptolite taxa are redescribed.
Fatty acid composition as an indicator of possible sources of nutrition for soft corals of the genusSinularia(Alcyoniidae)
Authors: Imbs Andrey B. , Latyshev Nikolay A. 
Published: October 2011

Fatty acids (FAs) composition of eight zooxanthellate soft corals,Sinularia leptoclados, S. flexibilis, S.aff.deformis, S. lochmodes, S. cf.muralis, S. densa, S. notandaandS. cruciatacollected in Van Phong Bay (Vietnam) were studied to identify possible origin of unsaturated FAs. The main FAs were 14:0, 16:0, 7-Me-16:1n-10, 16:1n-7, 16:2n-7, 18:0, 18:1n-9, 18:4n-3, 20:4n-6, 20:5n-3, 22:6n-3, 24:5n-6 and 24:6n-3. On the average, saturated, monounsaturated, and polyunsaturated FAs (PUFAs) contributed 35.6, 6.2 and 54.0% of total coral FAs, respectively. PUFAs of n-6 series predominated in all animals (n-6/n-3 > 1.6). The content of 20:4n-6 varied from 10.2 to 23.8%. The main n-3 PUFA was 18:4n-3 (on the average, 5.4%); the contribution of 20:5n-3 and 22:6n-3, typical PUFAs of marine organisms, was not more than 2.4 and 3.9%, respectively. InSinularia, PUFAs were produced by endosymbiotic dinoflagellates (zooxanthellae) and the coral host tissue, or obtained with food. Zooxanthellae can be considered as the source of C16PUFAs and 18:4n-3. The coral host synthesized 18:2n-7, 24:5n-6 and 24:6n-3 acids. The low content of 18:1n-7, saturated odd-chain FAs and saturated methyl-branched FAs indicated a negligible contribution of bacteria to total lipids ofSinularia. A comparison of the levels of diatom and dinoflagellate FA markers in coral and plankton lipids showed eukaryotic microalgae to play a secondary role in feeding ofSinularia. The high level of 20:4n-6 may be considered as an indicator of heterotrophic feeding ofSinularia.
Coral farming: effects of light, water motion and artificial foods
Authors: Forsman Zac H. , Kimokeo Bethany K. , Bird Christopher E. , Hunter Cynthia L. , Toonen Robert J. 
Published: October 2011

Improved coral cultivation will facilitate the reduction of wild harvesting, reef restoration, preservation of biodiversity, and the use of corals as model experimental organisms. In this study, we examine species-specific responses in growth and survival of corals from the effects of light, water motion and artificial (i.e. non-living aquarium trade) food supplements. Three species representing distinct, diverse and abundant coral genera were chosen (Montipora capitata(Mc), Porites compressa (Pc) and Pocillopora damicornis (Pd)) for three experiments to examine: (1) the interaction of water flow and light on growth and survival of Mc and Pc; (2) the effects of artificial foods on Mc, Pc and Pd; and (3) the effects of increasing dosage of artificial foods in an open system on Mc and Pc. Pc thrived at the highest light levels with low flow, while Mc exhibited bleaching and reduced growth in the same conditions and grew best in shaded treatments. High constant flow (~11 cm s-1) resulted in slightly less overall growth than low constant flow (~4 cm s-1). Some artificial foods resulted in a significant increase in growth in Mc and Pd, but not in Pc. These combined results suggest that Mc may be more heterotrophic than Pc. This study illustrates that each species has unique requirements for optimal growth conditions that can be determined by relatively simple and low cost experiments, but that ideal conditions for one species might not be generalized to others.
Mercury concentrations of two toothfish and three of its prey species from the Pacific sector of the Antarctic
Authors: Hanchet Stuart M. , Tracey Dianne , Dunn Alistair , Horn Peter , Smith Neville 
Published: October 2011

AbstractMuscle tissue samples were collected from Antarctic toothfish (Dissostichus mawsoni Norman) and Patagonian toothfish (D. eleginoides Smitt) in 1998 and from D. mawsoni and three of its prey species - Whitson's grenadier (Macrourus whitsoni (Regan)), ice fish (Chionobathyscus dewitti Andriashev & Neyelov), and blue antimora (Antimora rostrata (Günther)) - in 2006 to determine their mercury. Mercury levels were highly variable both within and between the five species studied but were positively correlated with fish length in four of the species. Once the factors length and year had been accounted for, the mercury levels in D. eleginoides were more than four times greater than in D. mawsoni. The low levels of mercury in D. mawsoni relative to its prey species and the four-fold difference in mercury concentrations between it and D. eleginoides were unexpected. Reasons for these different levels of bioaccumulation were explored including differences in diet, growth and longevity, and location. Differences in bioaccumulation between the two toothfish species could be explained partly through differences in their geographic distribution and differences in trophic position. However, the low levels of mercury in D. mawsoni relative to its prey species can only be explained by a lower rate of mercury assimilation and/or a higher rate of mercury elimination by D. mawsoni.