bluuebunny/crossref_metadata_2025_split huggingface dataset:
Limits to sustained energy intake XII: is the poor relation between resting metabolic rate and reproductive performance because resting metabolism is not a repeatable trait?
Authors: Duarte L. C. , Vaanholt L. M. , Sinclair R. E. , Gamo Y. , Speakman J. R. 
Published: December 2009

SUMMARY
Many studies have investigated the consequences of individual variation in resting metabolic rate at thermoneutrality (RMRt) on reproductive performance. Despite strong theoretical reasons for expecting such an association, results have generally been disappointing. A fundamental assumption of these studies is that RMRt is a repeatable trait. We examined repeatability of RMRt in female MF1 mice over short (15 days apart; N=238) and long intervals (110 days apart; N=33). In the long-term experiment, after the first RMRt measurement, females were separated in two groups: the first was kept virgin (N=16); the second was allowed to breed (N=17) and measured 15 days after they had weaned their pups. We also examined the association between RMRt and reproduction. We used Pearson's correlation (r) and intraclass correlation coefficients (ρ) to estimate repeatability. There was a strong effect of body mass on RMRt for all measurements. Over the short interval, repeatability was significant for body mass (r=0.86; ρ=0.86), RMRt (r=0.68; ρ=0.68,) and residual-RMRt (r=0.58; ρ=0.58). Over long intervals, repeatability of residual-RMRt was high in virgin females (r=0.59; ρ=0.60), but not in the breeders (r=0.38; ρ=0.39); body mass was repeatable only for non-breeders measured by r (r=0.55). There was no significant correlation between RMRt or residual-RMRt and litter size or litter mass. In conclusion, RMRt and residual-RMRt are highly repeatable traits in virgin MF1 female mice. The lack of association between non-reproductive RMRt and reproductive performance in MF1 mice does not come about because of its poor repeatability.
Eating chemically defended prey: alkaloid metabolism in an invasive ladybird predator of other ladybirds (Coleoptera: Coccinellidae)
Authors: Sloggett J. J. , Davis A. J. 
Published: December 2009

SUMMARY
By comparison with studies of herbivore physiological adaptation to plant allelochemicals, work on predator physiological adaptation to potentially toxic prey has been very limited. Such studies are important in understanding how evolution could shape predator diets. An interesting question is the specificity of predator adaptation to prey allelochemicals, given that many predators consume diverse prey with different chemical defences. The ladybird Harmonia axyridis, an invasive species in America, Europe and Africa, is considered a significant predatory threat to native invertebrates, particularly other aphid-eating ladybirds of which it is a strong intraguild predator. Although ladybirds possess species-specific alkaloid defences, H. axyridis exhibits high tolerance for allospecific ladybird prey alkaloids. Nonetheless, it performs poorly on species with novel alkaloids not commonly occurring within its natural range. We examined alkaloid fate in H. axyridis larvae after consumption of two other ladybird species, one containing an alkaloid historically occurring within the predator's native range (isopropyleine) and one containing a novel alkaloid that does not (adaline). Our results indicate that H. axyridis rapidly chemically modifies the alkaloid to which it has been historically exposed to render it less harmful: this probably occurs outside of the gut. The novel, more toxic alkaloid persists in the body unchanged for longer. Our results suggest metabolic alkaloid specialisation, in spite of the diversity of chemically defended prey that the predator consumes. Physiological adaptations appear to have made H. axyridis a successful predator of other ladybirds; however, limitations are imposed by its physiology when it eats prey with novel alkaloids.
The moment before touchdown: landing manoeuvres of the honeybee Apis mellifera
Authors: Evangelista C. , Kraft P. , Dacke M. , Reinhard J. , Srinivasan M. V. 
Published: December 2009

SUMMARY
Although landing is a crucial part of insect flight, it has attracted relatively little study. Here, we investigate, for the first time, the final moments of a honeybee's (Apis mellifera) landing manoeuvre. Using high-speed video recordings, we analyse the behaviour of bees as they approach and land on surfaces of various orientations. The bees enter a stable hover phase, immediately prior to touchdown. We have quantified behaviour during this hover phase and examined whether it changes as the tilt of the landing surface is varied from horizontal (floor), through sloped (uphill) and vertical (wall), to inverted (ceiling). The bees hover at a remarkably constant distance from the surface, irrespective of its tilt. Body inclination increases progressively as the tilt of the surface is increased, and is accompanied by an elevation of the antennae. The tight correlation between the tilt of the surface, and the orientation of the body and the antennae, indicates that the bee's visual system is capable of inferring the tilt of the surface, and pointing the antennae toward it. Touchdown is initiated by extending the appendage closest to the surface, namely, the hind legs when landing on horizontal or sloping surfaces, and the front legs or antennae when landing on vertical surfaces. Touchdown on inverted surfaces is most likely triggered by a mechanosensory signal from the antennae. Evidently, bees use a landing strategy that is flexibly tailored to the varying topography of the terrain.
Cellular mechanisms of acid secretion in the posterior midgut of the larval mosquito (Aedes aegypti)
Authors: Jagadeshwaran U. , Onken H. , Hardy M. , Moffett S. B. , Moffett D. F. 
Published: December 2009

SUMMARYThe gut contents of larval mosquitoes are alkalinized by the anterior midgut and reacidified by the posterior midgut. In the present study the cellular mechanisms of reacidification were studied in isolated, perfused posterior midgut by measuring the transepithelial voltage (Vte) and the rate of acid secretion as indicated by the color change of m-cresol purple during intervals of perfusion stop. The lumen-positive Vte and reacidification were significantly increased by serotonin (0.2 μmol l−1). The V-type H+-ATPase inhibitor concanamycin A (10 μmol l−1) on the luminal side inhibited acidification and decreased Vte. On the hemolymph side the carbonic anhydrase (CA) inhibitor acetazolamide (1 mmol l−1) almost abolished Vte, but had no effect on acidification. Similarly, hemolymph-side DIDS (0.1 mmol l−1), DPC (0.5 mmol l−1), amiloride (1 mmol l−1) and ouabain (2.5 mmol l−1) significantly reduced Vte, whereas Ba2+ (5 mmol l−1) was without effect. DPC and amiloride also reduced Vte when applied to the luminal side of the epithelium. Unilateral substitution of gluconate for Cl− affected Vte in a way consistent with a greater permeability for Cl−versus Na+. Cl− replacement in the lumen decreased Vte, whereas replacement on the hemolymph side increased it. Bilateral replacement left the control voltage unaffected. Na+ replacement on either side of the tissue reduced Vte to different degrees. Omission of luminal amino acids was followed by a significant decrease in Vte. Except for concanamycin A, none of the above manipulations impaired acidification, indicating that acidification requires only the apical proton pump. However, the chemical source of secreted H+ is still unknown and needs to be investigated.
Responses of alkaline phosphatase activity to phosphorus stress in Daphnia magna
Authors: McCarthy S. D. S. , Rafferty S. P. , Frost P. C. 
Published: December 2009

SUMMARY
We examined how alkaline phosphatase (AP) activity within the bodies and in the materials released by the crustacean Daphnia magna responds to variable algal food phosphorus (P)-content. We found that Daphnia eating P-poor food (C:P∼700) had significantly higher AP activity in their bodies on a mass-specific basis compared with individuals eating P-rich food (C:P∼100). This dietary P effect on AP activity was not altered by Daphnia starvation but was partially related to differences in the P concentration of animal body homogenates. By contrast, poor P-nutrition of Daphnia lowered AP activity in released materials compared with that measured from their P-sufficient conspecifics. Moreover, AP activity in Daphnia release was lowest in animals consuming P-poor food for longer time periods. Our results support the hypothesis that AP activity increases inside P-limited Daphnia as a mechanism to increase P-acquisition and retention from ingested algae in these nutritionally stressed animals. The lower level of AP activity present in the water of P-deprived animals could reflect a change from largely free to membrane-bound AP isotypes in the digestive tracts of P-starved animals or a decrease in the shedding of membrane-anchored AP from their intestinal lining. These results supplement accumulating evidence that P-poor algal food reduces the dietary mineral P available to Daphnia. In addition, animal body AP activity measurements, with some refinement, may prove useful as an in situ indicator of P-stress in aquatic consumers.
A Fully Photoreversible Supramolecular Polymer Having a Diarylethene Photoswitch
Authors: Takeshita Michinori , Hayashi Miyuki , Miyazaki Takashi 
Published: December 2009

Abstract
The particle size of a supramolecular polymer composed of a diarylethene photoswitch and two quadruple hydrogen-bonding sites having C17 chain changes photoreversibly in tetrahydrofuran at room temperature, while that in a CHCl3 solution is not photoreversible but is reversible with the assistance of heat.
Designing Chiral Quaternary Ammonium Polymers: Novel Type of Polymeric Catalyst for Asymmetric Alkylation Reaction
Authors: Itsuno Shinichi , Paul Devproshad K , Ishimoto Mikiya , Haraguchi Naoki 
Published: December 2009

Abstract
Optically active polymers containing chiral quaternary ammonium salt structure in their main chain have been prepared by simple polycondensation reaction. These polymers were used as catalyst for asymmetric alkylation of N-diphenylmethylidene glycine tert-butyl ester.
Highly Sensitive Detection of N1,N12-Diacetylspermine Based on Electrochemical Charge Accumulation
Authors: Yasukawa Tomoyuki , Inadumi Shingo , Harada Rie , Shinagawa Shingo , Nose Hiroshi , Mizutani Fumio 
Published: December 2009

Abstract
A novel immunosensor is presented based on a charge accumulation system using an electrode modified with a polymer containing [osmium(4,4′-dimethyl-2,2′-bipyridine)2chloride]+/2+ and horseradish peroxidase (Os/HRP polymer) to detect N1,N12-diacetylspermine (DiAcSpm). Glucose oxidase (GOx)-labeled antibody captured with immunoreaction on Os/HRP polymer catalyzed the production of hydrogen peroxide, which oxidizes [Os(bpy)2Cl]+ in polymer with HRP. [Os(bpy)2Cl]2+ was gradually accumulated in the polymer and reduced back to [Os(bpy)2Cl]+ by applying −0.1 V. This accumulation system of redox species allows enhancement of the response.
Electrochemical Formation of Mg–Li–Yb Alloys at Solid Magnesium Electrode from LiCl–KCl–YbCl3 Melts at Low Temperature
Authors: Ye Ke , Chen Ye , Zhang Milin , Han Wei , Yan Yongde , Wei Shuquan 
Published: December 2009

Abstract
This work presents a novel study on electrochemical preparation of Mg–Li–Yb alloys at a magnesium electrode in LiCl–KCl–YbCl3 melts at 743 K. Cyclic voltammograms showed that the reduction of ytterbium(III) ions is a stepwise reaction. The codeposition of Yb and Li takes place at magnesium electrode when the current intensity exceeds 60 mA in LiCl–KCl melts containing 2 wt % YbCl3. α, α + β, and β phases. Mg–Li–Yb alloys with different lithium contents were obtained by potentiostatic electrolysis at a magnesium electrode from LiCl–KCl melts with different concentrations YbCl3.
Manipulation of Single DNA Using a Micronanobubble Formed by Local Laser Heating on a Au-coated Surface
Authors: Fujii Sho , Kobayashi Katsuaki , Kanaizuka Katsuhiko , Okamoto Tetsuaki , Toyabe Shoichi , Muneyuki Eiro , Haga Masa-aki 
Published: December 2009

Abstract
We report a method for manipulating sequential single DNA strands by using a micronanobubble formed by local laser heating on a Au surface. DNA strands near the laser focal point were quickly pulled toward the focal point. This DNA pull-in phenomenon can be explained by Marangoni convection due to a micronanobubble generated by laser heating on the Au surface. The thickness of Au film plays a crucial role for absorbing the IR laser light.
MnIII Salen-type Single-molecule Magnet Fixed in a Two-dimensional Network
Authors: Kachi-Terajima Chihiro , Mori Erina , Eiba Tasuku , Saito Toshiaki , Kanadani Chikahide , Kitazawa Takafumi , Miyasaka Hitoshi 
Published: December 2009

Abstract
A two-dimensional network compound, [{Mn(saltmen)}4{Co(CN)6}](ClO4)·9H2O (2) (saltmen2− = N,N′-(1,1,2,2-tetramethylethylene)bis(salicylideneiminate)), was synthesized. Magnetic measurements characterized the [Mn2(saltmen)2]2+ subunit as a single-molecule magnet with an ST = 4 spin ground state, indicating that the MnIII dimer is magnetically isolated not only by the diamagnetic [Co(CN)6]3− unit but also by the space between the layers.
Preparation of Ester-group Substituted Allylic Zinc by Palladium-catalyzed Umpolung of γ-Acyloxy-α,β-unsaturated Ester by Bis(iodozincio)methane
Authors: Ueno Shizue , Sada Mutsumi , Matsubara Seijiro 
Published: December 2009

Abstract
Treatment of γ-acyloxy-α,β-unsaturated ester with bis(iodozincio)methane in the presence of palladium catalyst gave an allylic zinc carrying an ester group; the allylic zinc, which is prepared by this umpolung process, reacts with ketones regioselectively.
A Novel Synthesis of Mesoporous Nickel Oxide with Excellent Cycling Stability Used in Supercapacitors
Authors: Ni Wenbin , Wang Dengchao , Zhao Zhenzhen , Huang Zhongjie , Zhao Jianwei 
Published: December 2009

Abstract
Mesoporous nickel oxide is synthesized by a novel method by calcining a nickel–organic coordination complex precursor in this work. The prepared NiO has a uniform pore distribution evidenced by TEM and N2 adsorption–desorption tests. The NiO electrode presents a high specific capacitance of 143 F g−1, excellent rate capability (54.2% capacity retention at 100 mV s−1) and long cycling stability (no decrease in 1000 charge–discharge cycles), indicating a promising electrode material for supercapacitors.
Newborn Screening for Cystic Fibrosis by Use of a Multiplex Immunoassay
Authors: Lindau-Shepard Barbara A , Pass Kenneth A 
Published: December 2009

Abstract
Background: Since its beginnings, newborn screening for cystic fibrosis (CF) using an assay for immunoreactive trypsinogen (IRT) has been plagued by a high rate of false-positive results (screen positive, diagnosis negative), despite attempts to reduce this rate by use of altered cutoffs and second-tier DNA testing. IRT exists as 2 isoforms: IRT1 and IRT2, with IRT2 being more closely aligned with pancreatic disease, including CF. Assay standardization between programs is a continuing problem because the IRT assays currently in use variously recognize either 1 or both isoforms. Here we report the development of a multiplexed assay for both forms of IRT simultaneously.
Methods: Using 2 different Luminex bead sets, we developed assays for each IRT isoform separately and then combined them. Using the sum of IRT1 and IRT2 values (IRT1+IRT2), we compared the results with a CF kit currently in use.
Results: In a sample set consisting of 16 cases confirmed positive for CF, we established a cutoff at &gt;97 μg/L total IRT. Seven of 8 carriers with 1 CF mutation screen-positive by the standard method were also screen-positive by IRT1+IRT2. Of 32 cases screen-positive by standard IRT, 11 were screen-negative by IRT1+IRT2. None of these 11 cases had CF mutations identified by the screening program.
Conclusions: These data indicate that the multiplex method with specificity for 2 isoforms of IRT has performance comparable to that of a standard IRT method and the advantage of improved standardization by detection of the 2 isoforms.
Alternative Splicing Modulates Ubx Protein Function inDrosophila melanogaster
Authors: Reed Hilary C , Hoare Tim , Thomsen Stefan , Weaver Thomas A , White Robert A H , Akam Michael , Alonso Claudio R 
Published: December 2009

AbstractThe Drosophila Hox gene Ultrabithorax (Ubx) produces a family of protein isoforms through alternative splicing. Isoforms differ from one another by the presence of optional segments—encoded by individual exons—that modify the distance between the homeodomain and a cofactor-interaction module termed the “YPWM” motif. To investigate the functional implications of Ubx alternative splicing, here we analyze the in vivo effects of the individual Ubx isoforms on the activation of a natural Ubx molecular target, the decapentaplegic (dpp) gene, within the embryonic mesoderm. These experiments show that the Ubx isoforms differ in their abilities to activate dpp in mesodermal tissues during embryogenesis. Furthermore, using a Ubx mutant that reduces the full Ubx protein repertoire to just one single isoform, we obtain specific anomalies affecting the patterning of anterior abdominal muscles, demonstrating that Ubx isoforms are not functionally interchangeable during embryonic mesoderm development. Finally, a series of experiments in vitro reveals that Ubx isoforms also vary in their capacity to bind DNA in presence of the cofactor Extradenticle (Exd). Altogether, our results indicate that the structural changes produced by alternative splicing have functional implications for Ubx protein function in vivo and in vitro. Since other Hox genes also produce splicing isoforms affecting similar protein domains, we suggest that alternative splicing may represent an underestimated regulatory system modulating Hox gene specificity during fly development.
Fabrication of Nanomodified Anodes for Power Density Enhancement of Microbial Fuel Cells
Authors: Schaller Rebecca , Fan Yanzhen , Xu Shoutao , Fern Alan , Chaplen Frank , Liu Hong , Jiao Jun 
Published: December 2009

AbstractMicrobial fuel cells (MFCs) use microorganisms to simultaneously break down organic materials and generate electricity. One of the greatest challenges in the practical application of MFCs is to sufficiently increase their power generation. Nanomodified graphite carbon anodes were prepared for use in MFCs to enhance the electron transport from the microbes to the electrode. Nanomodification to the anodes included growth of nanoparticles and multi-walled carbon nanotubes (MWCNTs). Nanoparticles of various metals, including Au, Ni, Pd, and Fe, were synthesized through thermal annealing and Fe catalyzed MWCNTs were synthesized through chemical vapor deposition. Power density was measured in MFCs for each type of nanomodified electrodes. Significant increase in power density was observed for the MFC with anodes decorated with MWCNTs (with 50-100nm diameters).
Tunneling and anisotropic-tunneling magnetoresistance in iron nanoconstrictions fabricated by focused-ion-beam
Authors: Fernandez-Pacheco Amalio , De Teresa Jose M , Cordoba Rosa , Ibarra Ricardo 
Published: December 2009

AbstractWe report the magnetoresistance (MR) measurements in a nanoconstriction fabricated by focused-ion-beam (FIB) in the tunneling regime of conductance. The resistance of the contact was controlled during the fabrication process, being stable in the metallic regime, near the conductance quantum, and under high vacuum conditions. The metallic contact was deteriorated when exposed to atmosphere, resulting in a conduction mechanism by tunneling. The TMR was found to be of 3% at 24 K. The anisotropic tunneling magnetoresistance (TAMR) was around 2% for low temperatures, with a field angle dependence more abrupt than in bulk Fe. This preliminary result is promising for the application of this technique to fabricate stable ferromagnetic constrictions near the atomic regime of conductance, where high MR values are expected.
Simulation of Ion-beam Induced Etching and Deposition Using a Non-local Recoil-based Algorithm
Authors: Ebm Christoph , Hobler Gerhard 
Published: December 2009

AbstractIon-beam induced etching and deposition rates are proportional to the flux of recoils reaching the surface. Based on this finding we propose an improved algorithm for etching and deposition simulations. In this algorithm the recoil flux at each point on the surface is calculated by summing up the recoil fluxes originating from ions impinging on any other surface point. The latter are determined by interpolation in tables calculated by binary collision simulations. For concave surfaces a correction to this algorithm is proposed. Fluxes calculated by this model are in good agreement with binary collision simulations of collision cascades in the same 2-d structure. Consistent with experimental findings, the model predicts that deposited pillars are broader than the ion beam, while etched trenches do not show such broadening. The pillar broadening is related to the lateral straggling of the recoils.
My Modeling Nanocluster Formation During Ion Beam Synthesis
Authors: Yuan Chun-Wei , Yi Diana O. , Sharp Ian D. , Shin Swanee J. , Liao Christopher Y. , Guzman Julian , Ager Joel , Haller Eugene , Chrzan Daryl 
Published: December 2009

AbstractIon beam synthesis of nanoclusters is studied via both kinetic Monte Carlo simulations and the self-consistent mean-field solution to a set of coupled rate equations. Both approaches predict a steady-state shape for the cluster size distribution that depends only on a characteristic length determined by the ratio of the effective diffusion coefficient times the effective solubility to the ion flux. The average cluster size in the steady state regime is determined by the implanted species/matrix interface energy.
Quantum and Classical Molecular Dynamics Studies of the Threshold Displacement Energy in Si Bulk and Nanowires
Authors: Holmström Eero , Krasheninnikov Arkady , Nordlund Kai 
Published: December 2009

AbstractUsing quantum mechanical and classical molecular dynamics computer simulations, we study the full three-dimensional threshold displacement energy surface in Si. We show that the SIESTA density-functional theory method gives a minimum threshold energy of 13 eV that agrees very well with experiments, and predicts an average threshold displacement energy of 36 eV. Using the quantum mechanical result as a baseline, we discuss the reliability of the classical potentials with respect to their description of the threshold energies. We also examine the threshold energies for sputtering in a nanowire, and find that this threshold depends surprisingly strongly on which layer the atom is in.
Low-energy Ion Beam Biotechnology at Chiang Mai University
Authors: Yu Liangdeng , Anuntalabhochai S. 
Published: December 2009

AbstractMeV-ion beam has long been applied to biology research and applications for many decades as highly energetic ions are undoubtedly able to interact directly with biology molecules to cause changes in biology. However, low-energy ion beam at tens of keV and even lower has also been found to have significant biological effects on living materials. The finding has led to applications of ion-beam induced mutation and gene transfer. From the theoretical point of view, the low-energy ion beam effects on biology are difficult to understand since the ion range is so short that the ions can hardly directly interact with the key biological molecules for the changes. This talk introduces interesting aspects of low-energy ion beam biology, including basis of ion beam biotechnology and recent developments achieved in Chiang Mai University in relevant applications such as mutation and gene transfer and investigations on mechanisms involved in the low-energy ion interaction with biological matter such as eV-keV ion beam bombardments of naked DNA and the cell envelopes.