bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond the nuclear shell model
Authors: Dean David J.
Published: November 2007

Nuclear theorists are working to develop a comprehensive understanding of all nuclei. To achieve that goal, they'll need continuing advances in computational power along with data from new and challenging experiments.
What's your survey telling you?
Authors: Ivie Rachel , Czujko Roman
Published: November 2007

Subtle differences in the questionnaire can have large effects on the outcomes of a survey.
A Model of the Neural Mechanisms Underlying Multisensory Integration in the Superior Colliculus
Authors: Rowland Benjamin A , Stanford Terrence R , Stein Barry E
Published: November 2007

Much of the information about multisensory integration is derived from studies of the cat superior colliculus (SC), a midbrain structure involved in orientation behaviors. This integration is apparent in the enhanced responses of SC neurons to cross-modal stimuli, responses that exceed those to any of the modality-specific component stimuli. The simplest model of multisensory integration is one in which the SC neuron simply sums its various sensory inputs. However, a number of empirical findings reveal the inadequacy of such a model; for example, the finding that deactivation of cortico-collicular inputs eliminates the enhanced response to a cross-modal stimulus without eliminating responses to the modality-specific component stimuli. These and other empirical findings inform a computational model that accounts for all of the most fundamental aspects of SC multisensory integration. The model is presented in two forms: an algebraic form that conveys the essential insights, and a compartmental form that represents the neuronal computations in a more biologically realistic way.
Eye Position Affects Audio — Visual Fusion in Darkness
Authors: Hartnagel David , Bichot Alain , Roumes Corinne
Published: November 2007

We investigated the frame of reference involved in audio – visual (AV) fusion over space. This multisensory phenomenon refers to the perception of unity resulting from visual and auditory stimuli despite their potential spatial disparity. The extent of this illusion depends on the eccentricity in azimuth of the bimodal stimulus (Godfroy et al, 2003 Perception32 1233–1245). In a previous study, conducted in a luminous environment, Roumes et al 2004 ( Perception33 Supplement, 142) have shown that variation of AV fusion is gaze-dependent. Here we examine the contribution of ego- or allocentric visual cues by conducting the experiment in total darkness. Auditory and visual stimuli were displayed in synchrony with various spatial disparities. Subjects had to judge their unity (‘fusion’ or ‘no fusion’). Results showed that AV fusion in darkness remains gaze-dependent despite the lack of any allocentric cues and confirmed the hypothesis that the reference frame of the bimodal space is neither head-centred nor eye-centred.
Assessing the Automaticity of the Exogenous Orienting of Tactile Attention
Authors: Santangelo Valerio , Spence Charles
Published: November 2007

We examined whether or not abrupt tactile onsets are capable of exogenously capturing tactile spatial attention when visual spatial attention is focused elsewhere. In experiment 1, we compared performance under dual-task conditions (where participants performed a tactile exogenous cuing task and a rapid serial visual presentation—RSVP—task at the same time) with their performance under single-task conditions (where the participants had to perform only the cuing task, although the RSVP stream was still presented in the background) and to a no-stream condition (where only the cuing task was presented). Tactile cuing was completely suppressed in both the dual-task and single-task conditions, showing that exogenous tactile spatial orienting is modulated by visual-spatial attention, which hence appears to be far from truly automatic. In experiment 2, we demonstrated that the abolishment of exogenous tactile orienting was not caused by the transient presentation of abrupt onset stimuli (letters). These results therefore show that exogenous spatial attentional orienting toward abrupt peripheral tactile stimuli is possible as long as perceptual resources are not depleted by a perceptually demanding (RSVP) task.
Gaze Behaviour in Audiovisual Speech Perception: Asymmetrical Distribution of Face-Directed Fixations
Authors: Everdell Ian T , Marsh Heidi , Yurick Micheal D , Munhall Kevin G , Paré Martin
Published: November 2007

Speech perception under natural conditions entails integration of auditory and visual information. Understanding how visual and auditory speech information are integrated requires detailed descriptions of the nature and processing of visual speech information. To understand better the process of gathering visual information, we studied the distribution of face-directed fixations of humans performing an audiovisual speech perception task to characterise the degree of asymmetrical viewing and its relationship to speech intelligibility. Participants showed stronger gaze fixation asymmetries while viewing dynamic faces, compared to static faces or face-like objects, especially when gaze was directed to the talkers' eyes. Although speech perception accuracy was significantly enhanced by the viewing of congruent, dynamic faces, we found no correlation between task performance and gaze fixation asymmetry. Most participants preferentially fixated the right side of the faces and their preferences persisted while viewing horizontally mirrored stimuli, different talkers, or static faces. These results suggest that the asymmetrical distributions of gaze fixations reflect the participants' viewing preferences, rather than being a product of asymmetrical faces, but that this behavioural bias does not predict correct audiovisual speech perception.
N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2): an Efficient Reagent for the Synthesis of Chemical Weapons Convention-Related Dialkyl-N,N-dialkylphosphoramidates from Dialkylphosphites
Authors: Gupta Arvind K. , Pardasani Deepak , Gupta Hemendra K. , Dubey Devendra K.
Published: November 2007

The present paper describes the one-pot synthesis of dialkyl N,N-dialkylphosphoramidates (DADAP) from dialkylphosphites and dialkylamines using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as chlorinating reagent. DADAP belong to the schedule 2.B.6 category of the Chemical Weapons Convention (CWC), as they are the important markers of the chemical warfare agent tabun and its analogues. The study was undertaken to develop the spectral database of DADAP for verification of CWC. The reported synthetic strategy can be adopted to rapidly synthesize several analogues of DADAP during official proficiency tests.
Asymmetric Synthesis using Organoboranes. Relative Effectiveness of the B-Halobis(terpenyl)boranes for the Enantioselective Halogenative Cleavage of Representative meso-Epoxides
Authors: Roy Chandra D. , Brown Herbert C.
Published: November 2007

A comparative study of the relative effectiveness of various Ter2BX, such as dEap2BX, lEap2BX, 2-dIcr2BX, 4-dIcr2BX, and lCleap2BX along with dIpc2BX for the asymmetric ring opening of three representative meso-epoxides (cyclohexene, cyclopentene, and cis-2,3-butene oxides) is reported. Among all the reagents studied, 2-dIcr2BCl (78–80%) demonstrated significant improvement in enantiomeric excess over a previously explored reagent, dIpc2BCl (41%), especially for meso-cyclohexene oxide. Although all these three reagents, dIpc2BBr, dEap2BBr, and 2-dIcr2BBr provided comparable enantiomerically enriched 2-bromocyclohexan-1-ol (76–86%) from meso-cyclohexene oxide, the carene-based reagent, 2-dIcr2BBr showed considerable improvements in enantiomeric excesses in the cases of meso-cyclopentene oxide (67%) and meso-cis-2,3-butene oxide (78%) than those achieved with previously reported reagent, dIpc2BBr (57 and 61% respectively). The enantioselectivity of the reaction was observed to be highly substrate dependent. The present study represents a significant advance in asymmetric synthesis using the chiral organoborane chemistry.
Silica Chloride-Catalyzed One-Pot Isomerization - Chlorination, Arylation, and Etherification of Baylis - Hillman Adducts
Authors: Shanmugam Ponnusamy , Viswambharan Baby , Vaithiyanathan Vadivel
Published: November 2007

A convenient and efficient one-pot isomerization–chlorination, arylation, and etherification of several Baylis–Hillman adducts with silica chloride, an eco-friendly heterogeneous catalyst, silica chloride–arenes, and silica chloride–saturated and unsaturated alcohols as reagent systems are reported. These reactions furnished highly functionalized isomerized Baylis–Hillman derivatives in good yield. The efficiency and necessity of silica chloride catalyst was compared with thionyl chloride. A plausible mechanism of the reaction is proposed.
The Preparation of Solid-Supported Peptide Boronic Acids Derived from 4-Borono-L-phenylalanine and their Affinity for Alizarin
Authors: Duggan Peter J. , Offermann Daniel A.
Published: November 2007

A library of solid-supported pentapeptide diboronic acids, a ‘lysine series’ and an ‘arginine series’, has been efficiently prepared using N-Fmoc-4-pinacolatoborono-l-phenylalanine and standard solid phase peptide synthesis methods. A technique for measuring the affinity of the chromophoric diol, alizarin, to the solid-supported peptide boronic acids has been developed. Considerable variation in alizarin binding strengths, both within and between arginine and lysine series was observed, with association constants in the range 200–1100 M–1 being recorded. The selective binding characteristics of these boronic acid–peptide hybrids suggest their potential use in carbohydrate sensors and cell-specific diagnostics and therapeutics.
Characterization of Eucalyptus and Chemically Related Exudates by Nuclear Magnetic Resonance Spectroscopy
Authors: Lambert Joseph B. , Wu Yuyang , Kozminski Michael A. , Santiago-Blay Jorge A.
Published: November 2007

Exudates from six species of the genus Eucalyptus and one of the genus Corymbia (formerly Eucalyptus), from the family Myrtaceae, have been characterized by solid-state 13C and solution 1H NMR spectroscopy for the first time. Although these eucalypt kinos, as these exudates often are called, resemble resin (terpenoid) and gum (carbohydrate) exudates in physical appearance, their NMR spectra are dramatically different. In addition to lacking the characteristic terpene saturated resonances, they exhibit strong unsaturated resonances, which are weak for resins and absent for gums. We additionally report that exudates from genera of several other families of flowering plants (Amyris, Centrolobium, Guaiacum, Liquidambar, and Prosopis) also exhibit part or all of this kino spectroscopic signature.
Two New Three-Dimensional Networks Constructed on Polyoxovanadates
Authors: Qi Yan-fei , Xiao Dongrong , Wang Enbo , Zhang Zhiming , Wang Xinlong
Published: November 2007

To investigate the role of polyoxovanadates in network connectivity, two new organic–inorganic hybrid vanadates with three-dimensional entangled coordination frameworks, namely [Cu2(biim)3V4O12] 1 and [Co2(biim)3V4O12]·4H2O 2 have been synthesized and characterized by
infrared (IR), thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. Crystal data for compound 1: triclinic, P-1, a 9.504(2), b 10.650(2), c 11.993(2) Å; α 72.13(3), β 76.02(3), γ 65.40(3)°; V 1041.4(4) Å3, Z 2, R(final) 0.0492. Crystal data for compound 2: triclinic, P-1, a 9.037(3), b 10.577(2), c 11.9470(2) Å; α 87.80(3), β 81.71(3), γ 85.29(3)°; V 1125.8(4) Å3, Z 1, R(final) 0.0774. Compound 1 is a three-dimensional inclined hetero-catenated framework designed from two two-dimensional sub-layers, [Cu(biim)V4O12] and [Cu(biim)2]. Compound 2 is a rare case of a self-catenated ‘ilc’ network that displays an unusual 424·5·63 topology with the binuclear {Co2O4N6} units as eight-connected nodes.
Bi(NO3)3 - Al2O3-Mediated Efficient Synthesis of 4-Aryl-2,6-dicoumarinylpyridines Under Solventless Conditions
Authors: Verma Anil K. , Koul Summon , Kapoor Kamal K. , Razdan Tej K.
Published: November 2007

A new efficient and eco-friendly methodology has been developed for the synthesis of 4-aryl-2,6-dicoumarinylpyridines from coumarinylchalcones and urea, using Bi(iii) nitrate–Al2O3 as catalyst. Coumarinylchalcones were in turn prepared from salicylaldehyde and ethylacetoacetate by the tandem reaction with aldehydes on the surface of Bi(iii) nitrate–Al2O3 in the presence of the co-catalyst Zn(ii) chloride.
Use of the Anti-Oxidant Butylated Hydroxytoluene in situ for the Synthesis of Readily Oxidized Compounds: Application to the Synthesis of the Moth Pheromone (Z,Z,Z)-3,6,9-Nonadecatriene
Authors: Davies Noel W. , Meredith Graham , Molesworth Peter P. , Smith Jason A.
Published: November 2007

The triene (Z,Z,Z)-3,6,9-nonadecatriene was synthesized in three steps from methyl linolenate. The key to the synthesis was the use of the anti-oxidant butylated hydroxytoluene in situ to provide protection of the unstable triene from autoxidation during reaction workup. This simple modification resulted in an increase in the yield from 20 to 85% over three steps.
Selective Monoesterification of Malonic Acid Catalyzed by Boric Acid
Authors: Levonis Stephan M. , Bornaghi Laurent F. , Houston Todd A.
Published: November 2007

Boric acid catalyzes the monoesterification of malonic acid, likely through a chelation mechanism that is not available to the monoester product. Under more forcing conditions, diesters form to some extent, but conditions can be optimized to favour the monoester product (56–80%). With the easily handled solid acid catalyst, these reactions can be run with excess alcohol as solvent or with stoichiometric amounts of alcohol in acetonitrile with moderate heating.
Mono- and Di-nuclear Gold(I) Complexes Containing 1,12-Dicarba-closo-dodecaborane(12)
Authors: Ioppolo Joseph A. , Kepert Cameron J. , Price David J. , Rendina Louis M.
Published: November 2007

The first examples of gold(i) complexes containing monodentate diphenylphosphine-1,12-carborane and bidentate 1,12-bis(diphenylphosphine)-1,12-carborane ligands are reported.
Biodegradable Ionic Liquids: Selected Synthetic Applications
Authors: Bouquillon Sandrine , Courant Thomas , Dean Darrell , Gathergood Nicholas , Morrissey Saibh , Pegot Bruce , Scammells Peter J. , Singer Robert D.
Published: November 2007

3-Methyl-1-(propyloxycarbonylmethyl)imidazolium octylsulfate 1a and 3-methyl-1-(pentyloxycarbonylmethyl)imidazolium octylsulfate 2a are ionic liquids that have previously been shown to be readily biodegradable in the CO2 headspace test (ISO 14593). In the present study, these ionic liquids were evaluated as reaction media for Diels–Alder and hydrogenation reactions. The comparison of the performance of these two designer solvents in these reactions with those conducted in other, non-biodegradable ionic liquids has demonstrated that they are comparable and viable solvents.
Synthesis, Decoding, and Preliminary Screening of a Bead-Supported Split-Pool Library of Triboronic Acid Receptors for Complex Oligosaccharides
Authors: Manku Sukhdev , Hall Dennis G.
Published: November 2007

A controlled synthesis of a prototypic bead-supported combinatorial library of 289 triamine-derived triboronic acid receptors for oligosaccharides was achieved using the split-pool strategy with bead encoding using the method of partial termination synthesis. Although a preliminary screening of the library against the Lewis-b tetrasaccharide in neutral water failed to show tight-binding receptors, single beads from the library can be decoded efficiently using high performance liquid chromatography with electrospray mass spectrometric detection. This proof-of-concept could become generally applicable with the help of improved glycoside-binding boronic acid units.
Comparison of the expression profiles of susceptible and resistant Eucalyptus grandis exposed to Puccinia psidii Winter using SAGE
Authors: Moon David H. , Salvatierra Guillermo R. , Caldas Danielle G. G. , Gallo de Carvalho Mayra C. C. , Carneiro Raphael T. , Franceschini Lívia M. , Oda Shinitiro , Labate Carlos A.
Published: November 2007

Eucalyptus grandis Hill ex Maiden and its hybrids are commonly planted by the Brazilian pulp and paper industry, but they are the most susceptible to the neotropical rust disease caused by Puccinia psidii Winter. In an initial attempt to understand the mechanisms of resistance, we constructed two contrasting Serial Analysis of Gene Expression (SAGE) libraries using susceptible and resistant individuals from a segregating half-sibling E. grandis population. Using the Z-test we identified tags differentially expressed between the libraries, preferentially 239 in the susceptible and 232 in the resistant type individuals. Using public (Expressed Sequence Tags) EST databases, 40 of the susceptible and 70 of the resistant tags matched ESTs and were annotated. By comparing the type of genes and their expression levels, distinct differences between the libraries were observed. Susceptible plants showed gene expression linked to leaf senescence, generalised stress responses and detoxification, and are apparently incapable of inducing a competent host defence response. On the other hand, resistant plants showed genes upregulated for cellular polarisation, cytoskeleton restructuring, vesicle transport, and cellulose and lignin biosynthesis. In the resistant individuals, evidence for systemic resistance, anti-oxidative responses and a hypersensitive response was also observed, although no R gene was identified.
Characterisation of lanthanum toxicity for root growth of Arabidopsis thaliana from the aspect of natural genetic variation
Authors: Kobayashi Yuriko , Ikka Takashi , Kimura Kazuhiko , Yasuda Orito , Koyama Hiroyuki
Published: November 2007

The mechanism of lanthanum (La3+) toxicity on root growth of Arabidopsis was studied by physiological and genetic approaches using Landsberg erecta (Ler) × Columbia (Col) recombinant inbred lines (RILs) and other natural accessions. Quantitative trait locus (QTL) analyses revealed regulation of La3+ tolerance of the Ler × Col RILs by multiple genetic factors consisted of three significant QTLs and seven epistatic interacting loci pairs. The La content in the root tip was not correlated with La3+ tolerance in the RILs, indicating that the observed La3+ rhizotoxicity was not related to direct toxicity of La3+ in the symplast. The La3+ tolerance of root growth in the RILs was not correlated with Al3+ and Cu2+ tolerances, but was correlated with tolerances for other rare earth elements, including Gd3+, a known Ca2+ channel antagonist, and verapamil, a Ca2+ channel blocker. The genetic architecture of verapamil tolerance in root growth, which was identified by QTL analysis, was closely related to that of La3+ tolerance. La3+ tolerance and verapamil tolerance or Gd3+ tolerance in natural accessions of Arabidopsis also showed a positive correlation. These results indicate that the major La3+ toxicity on the root growth of Arabidopsis may involve its action as a Ca2+ channel antagonist.
Effect of a synthetic lure on site visitation and bait uptake by foxes (Vulpes vulpes) and wild dogs (Canis lupus dingo, Canis lupus familiaris)
Authors: Hunt Rob J. , Dall David J. , Lapidge Steven J.
Published: November 2007

Application of synthetic fermented egg (SFE), via aerosol, to the surface of bait stations increased site visitation by wild dogs and foxes when compared with the use of buried baits alone. An associated increase in bait uptake by foxes at SFE-treated bait stations was observed when compared with bait uptake at untreated stations, although this effect diminished with time, possibly due to the use of non-lethal baits leading to the discovery of all bait stations and the habituation of animals to sites of reward. Bait uptake by wild dogs, although limited, occurred only at stations treated with SFE. Use of an aerosol based form of SFE allowed an ease of field application not previously associated with the use of synthetic lures.
Current and future threats from non-indigenous animal species in northern Australia: a spotlight on World Heritage Area Kakadu National Park
Authors: Bradshaw Corey J. A. , Field Iain C. , Bowman David M. J. S. , Haynes Chris , Brook Barry W.
Published: November 2007

Non-indigenous animal species threaten biodiversity and ecosystem stability by damaging or transforming habitats, killing or out-competing native species and spreading disease. We use World Heritage Area Kakadu National Park, northern Australia, as a focal region to illustrate the current and potential threats posed by non-indigenous animal species to internationally and nationally recognised natural and cultural values. Available evidence suggests that large feral herbivores such as Asian swamp buffalo, pigs and horses are the most ecologically threatening species in this region. This may reflect the inherent research bias, because these species are highly visible and impact primary production; consequently, their control has attracted the strongest research and management efforts. Burgeoning threats, such as the already established cane toad and crazy ant, and potentially non-indigenous freshwater fish, marine invertebrates and pathogens, may cause severe problems for native biodiversity. To counter these threats, management agencies must apply an ongoing, planned and practical approach using scientifically based and well funded control measures; however, many stakeholders require direct evidence of the damage caused by non-indigenous species before agreeing to implement control. To demonstrate the increasing priority of non-indigenous species research in Australia and to quantify taxonomic and habitat biases in research focus, we compiled an extensive biography of peer-reviewed articles published between 1950 and 2005. Approximately 1000 scientific papers have been published on the impact and control of exotic animals in Australia, with a strong bias towards terrestrial systems and mammals. Despite the sheer quantity of research on non-indigenous species and their effects, management responses remain largely ad hoc and poorly evaluated, especially in northern Australia and in high-value areas such as Kakadu National Park. We argue that improved management in relatively isolated and susceptible tropical regions requires (1) robust quantification of density–damage relationships, and (2) the delivery of research findings that stimulate land managers to develop cost-effective control and monitoring programs.
Home range and habitat use of a low-density population of greater gliders, Petauroides volans (Pseudocheiridae: Marsupialia), in a hollow-limiting environment
Authors: Smith Geoffrey C. , Mathieson Michael , Hogan Luke
Published: November 2007

Greater gliders, Petauroides volans, were radio-tracked within a large tract of forest in the dry inland of southern Queensland. This forest has been commercially logged for timber for more than 100 years. Home-range estimates ranged from 1.4 ha (female) to 19.3 ha (male). Minimum convex polygon (MCP) estimates were larger for males (average, 11.5 ha) than females (average, 3.3 ha) and combined (6.8 ha, sexes pooled) were larger than estimates from other Australian populations. Gliders were located foraging in myrtaceous tree species only, using mostly Eucalyptus moluccana, E. fibrosa and Corymbia citriodora. E. moluccana was used for foraging more frequently than would be expected on the basis of its availability in the forest. E. fibrosa and C. citriodora were used in proportion to their availability in the forest. Gliders were not seen foraging in non-myrtaceous species or myrtaceous trees <20 cm diameter at breast height (dbh), preferring trees in 30–70-cm dbh classes and as ‘mature’ and ‘over-mature’ classified according to growth-stage characteristics. Den tree species included the same species used for foraging as well as dead trees (16% of den trees). E. fibrosa and E. tereticornis were preferred significantly more than expected by their availability in the forest. Non-myrtaceous species were not used as live den trees. Large (dbh >50 cm) and old living trees (in deteriorating and senescent condition: ‘late mature’ and ‘over-mature’ categories) were primarily used as den trees. Individual gliders utilised 4–20 den trees. Females utilised more den trees per unit area of home range (3.8 den trees ha–1, maximum) than males (0.9 den trees ha–1, maximum). Fewer den trees were used per unit area of home range than by gliders at a coastal location with approximately the same latitude. The density of live stems containing hollows suitable as dens is currently lower than 1 tree ha–1 in some parts of the study forest. Gliders were two and half times less likely to be observed during standardised spotlighting surveys in the study area than elsewhere in southern Queensland. It is likely that low availability of den trees is contributing to large home ranges and the apparent low population density observed in this study.
Usefulness of funnel traps in catching small reptiles and mammals, with comments on the effectiveness of the alternatives
Authors: Thompson Graham G. , Thompson Scott A.
Published: November 2007

Funnel traps were used in conjunction with pit traps (PVC buckets and pipes), Elliott traps and cage traps at 10 sites in southern Western Australia to examine sampling bias of trap types. Funnel traps seldom catch small mammals but catch more of the medium-sized and large terrestrial, diurnal snakes and some of the widely foraging, medium-sized skinks, medium-sized dragon lizards and arboreal geckos that climb out of PVC pit traps. For pit traps, buckets catch more reptiles, particularly smaller ones, than pipes. However, pipes catch more mammals than buckets. Elliott traps catch the same suite of small mammals as pipes plus some of the large, trappable species, such as Rattus spp. Cage traps are useful for trapping Tiliqua spp. and medium-sized mammals such as possums and bandicoots that are unlikely to be caught in pit and funnel traps. Funnel traps, pit traps and cage traps should be used in surveys of small terrestrial vertebrates to determine species richness and relative abundance in Western Australia and probably elsewhere. However, as cage traps are mostly useful for catching Tiliqua spp. and medium-sized mammals, they need only be used in faunal surveys undertaken for environmental impact assessments specifically targeting these species.
Increasing the target-specificity of ERADICAT® for feral cat (Felis catus) control by encapsulating a toxicant
Authors: Hetherington Cheryl A. , Algar David , Mills Harriet , Bencini Roberta
Published: November 2007

ERADICAT®, a sausage-type meat bait, has been developed for use in managing feral cat (Felis catus) populations throughout Western Australia. However, concern about potential exposure of non-target species to bait-delivered toxicants has led to the development of a technique to more specifically target feral cats using a pellet. Research into the consumption, by cats and native animals, of toxic pellets implanted within the ERADICAT® bait has been simulated using ball bearings as a substitute pellet. Results from our work indicate that encapsulating the toxicant may pose less risk of poisoning to chuditch (Dasyurus geoffroii), woylies (Bettongia pencillata) and southern brown bandicoots (Isoodon obesulus) as they consumed significantly fewer ball bearings (P = 0.003, <0.001, <0.001) than semi-feral cats (P = 0.07). Theoretically, a toxic pellet will not reduce the effectiveness of the ERADICAT® bait as there was no significant difference between consumption of baits and the consumption of ball bearings in feral cats (P = 0.07). Therefore, baits containing a toxic pellet have the potential to be a more selective method to control feral cats.
Effects of bait type and deployment strategy on uptake by free-living badgers
Authors: Cagnacci Francesca , Massei Giovanna , Cowan David P. , Walker Neil , Delahay Richard J.
Published: November 2007

Baits are increasingly used in wildlife management to deliver orally administered vaccines and contraceptives. The efficacy and cost-effectiveness of vaccination or fertility-control campaigns can be substantially affected by bait uptake rates. This study assessed whether bait type and deployment strategy affected bait uptake by free-living badgers (Meles meles L.). Six social groups of badgers were presented with three bait types (meat, fruit, cereals) and two deployment strategies (dispersed single baits versus aggregated multiple baits at fixed baiting stations) for six weeks. In each social group, the type of bait and deployment strategy were rotated every week so that by the end of the test every group had experienced all combinations. On three days, biomarkers (ethyl iophenoxic acid, propyl iophenoxic acid and rhodamine B) were added to the baits to determine the proportion of badgers ingesting these baits. The results indicated that both bait type and deployment strategy affected the proportion of baits eaten by badgers and the number of badgers gaining access to baits. Meat and fruit baits were taken significantly more frequently than cereals, and dispersed meat baits had the highest rates of disappearance. Biomarker levels suggested that the proportion of badgers that gained access to all baits was substantially lower when baits were aggregated, although small sample sizes prevented statistical assessment of this effect. The results suggest that dispersed single baits are likely to be consumed in greater proportions by a higher number of individual badgers than multiple baits at fixed stations.
Detecting predation of a burrow-nesting seabird by two introduced predators, using stable isotopes, dietary analysis and experimental removals
Authors: Harper Grant A.
Published: November 2007

Burrowing seabirds are vulnerable to extirpation by introduced predators such as rats, but much evidence of predation is circumstantial. On Taukihepa, an island off southern New Zealand, two possible predators exist with sooty shearwaters (Puffinus griseus): the weka (Gallirallus australis), a large rail, and the ship rat (Rattus rattus), both introduced to the island. It was expected that chick predation would be principally by weka, the much larger of the two predators. To measure losses of sooty shearwater chicks to weka or rats, nests were monitored with burrow-scopes at six sites in the summers of 2003–04 and 2004–05. In three of the sites rats were removed on 4-ha grids by trapping. In the other three sites rats were not trapped. In addition, weka were removed from all six sites in 2005. Concurrent diet analysis of weka and rat stomachs was undertaken as well as stable isotopic analysis (δ13C, δ15N) of samples from rats and weka. These were compared with possible prey items including sooty shearwaters. Additional stable isotope samples were taken from Pacific rats (Rattus exulans), a small rat species present with weka and sooty shearwaters on nearby Moginui Island. Weka diet comprised ~40% of bird remains by volume and calculations using Isosource, an isotopic source portioning model, estimated sooty shearwaters contributed 59% (range: 15–71%) of weka diet during the sooty shearwater chick-raising period. Ship rats, in contrast, had very depleted δ13C isotope signatures compared with sooty shearwaters and bird remains contributed <9% of diet by volume, with Isosource calculations suggesting that ship rats consumed more passerine birds (mean: 30%; range 5–51%) than sooty shearwaters (mean 24%; range: 0–44%). In both summers, more chicks were lost on sites from which rats had been removed than on control sites. When weka were removed in 2005, fewer chicks were lost than in 2004 and significantly fewer weka-killed chicks were found on weka-removal sites than on non-removal sites. Weka were the principal predator of sooty shearwater chicks, depredating an estimated 9.9% of nests. Combining several techniques quantified the loss and identified the principal predator of a seabird in decline.
Effects of drought on weight, survival and breeding success of agile antechinus (Antechinus agilis), dusky antechinus (A. swainsonii) and bush rats (Rattus fuscipes)
Authors: Parrott Marissa L. , Ward Simon J. , Temple-Smith Peter D. , Selwood Lynne
Published: November 2007

Extreme weather conditions, such as drought, significantly decrease the survival and breeding success of numerous species. Despite the frequent occurrence of such conditions in Australia, little is known about the effects of changing environmental conditions on the native small mammals. This study, conducted from 2002 to 2004, focussed on sympatric wild populations of the agile antechinus (Antechinus agilis), with more limited information on the dusky antechinus (A. swainsonii) and the bush rat (Rattus fuscipes). Bodyweights of agile antechinus before and during the breeding season were significantly lower in 2003 (drought) than in 2002 or 2004. Survival of female agile antechinus and the number of young per litter also decreased significantly during drought. In contrast, the dusky antechinus showed no difference in mean bodyweights between years, high survival rates of females and similar litter sizes in 2002 and 2003. There was also no difference in bodyweight of bush rats between years. Low rainfall was recorded during pregnancy and lactation in the agile antechinus, but rainfall was higher during pregnancy and lactation in the dusky antechinus. The survival and breeding success of the agile antechinus may have been adversely affected by a combination of interspecific competition, timing of the breeding season and severity of the drought.
In silico
and
in vitro
pharmacogenetic analysis in mice
Authors: Guo Yingying , Lu Peng , Farrell Erin , Zhang Xun , Weller Paul , Monshouwer Mario , Wang Jianmei , Liao Guochun , Zhang Zhaomei , Hu Steven , Allard John , Shafer Steve , Usuka Jonathan , Peltz Gary
Published: November 2007

Combining the experimental efficiency of a murine hepatic
in vitro
drug biotransformation system with
in silico
genetic analysis produces a model system that can rapidly analyze interindividual differences in drug metabolism. This model system was tested by using two clinically important drugs, testosterone and irinotecan, whose metabolism was previously well characterized. The metabolites produced after these drugs were incubated with hepatic
in vitro
biotransformation systems prepared from the 15 inbred mouse strains were measured. Strain-specific differences in the rate of 16α-hydroxytestosterone generation and irinotecan glucuronidation correlated with the pattern of genetic variation within
Cyp2b9
and
Ugt1a
loci, respectively. These computational predictions were experimentally confirmed using expressed recombinant enzymes. The genetic changes affecting irinotecan metabolism in mice mirrored those in humans that are known to affect the pharmacokinetics and incidence of adverse responses to this medication.
Regulatory evolution in proteins by turnover and lineage-specific changes of cyclin-dependent kinase consensus sites
Authors: Moses Alan M. , Liku Muluye E. , Li Joachim J. , Durbin Richard
Published: November 2007

Evolutionary change in gene regulation is a key mechanism underlying the genetic component of organismal diversity. Here, we study evolution of regulation at the posttranslational level by examining the evolution of cyclin-dependent kinase (CDK) consensus phosphorylation sites in the protein subunits of the pre-replicative complex (RC). The pre-RC, an assembly of proteins formed during an early stage of DNA replication, is believed to be regulated by CDKs throughout the animals and fungi. Interestingly, although orthologous pre-RC components often contain clusters of CDK consensus sites, the positions and numbers of sites do not seem conserved. By analyzing protein sequences from both distantly and closely related species, we confirm that consensus sites can turn over rapidly even when the local cluster of sites is preserved, consistent with the notion that precise positioning of phosphorylation events is not required for regulation. We also identify evolutionary changes in the clusters of sites and further examine one replication protein, Mcm3, where a cluster of consensus sites near a nucleocytoplasmic transport signal is confined to a specific lineage. We show that the presence or absence of the cluster of sites in different species is associated with differential regulation of the transport signal. These findings suggest that the CDK regulation of MCM nuclear localization was acquired in the lineage leading to
Saccharomyces cerevisiae
after the divergence with
Candida albicans
. Our results begin to explore the dynamics of regulatory evolution at the posttranslational level and show interesting similarities to recent observations of regulatory evolution at the level of transcription.
Prediction of the structure of symmetrical protein assemblies
Authors: André Ingemar , Bradley Philip , Wang Chu , Baker David
Published: November 2007

Biological supramolecular systems are commonly built up by the self-assembly of identical protein subunits to produce symmetrical oligomers with cyclical, icosahedral, or helical symmetry that play roles in processes ranging from allosteric control and molecular transport to motor action. The large size of these systems often makes them difficult to structurally characterize using experimental techniques. We have developed a computational protocol to predict the structure of symmetrical protein assemblies based on the structure of a single subunit. The method carries out simultaneous optimization of backbone, side chain, and rigid-body degrees of freedom, while restricting the search space to symmetrical conformations. Using this protocol, we can reconstruct, starting from the structure of a single subunit, the structure of cyclic oligomers and the icosahedral virus capsid of satellite panicum virus using a rigid backbone approximation. We predict the oligomeric state of EscJ from the type III secretion system both in its proposed cyclical and crystallized helical form. Finally, we show that the method can recapitulate the structure of an amyloid-like fibril formed by the peptide NNQQNY from the yeast prion protein Sup35 starting from the amino acid sequence alone and searching the complete space of backbone, side chain, and rigid-body degrees of freedom.
Remodeling a DNA-binding protein as a specific
in vivo
inhibitor of bacterial secretin PulD
Authors: Mouratou Barbara , Schaeffer Francis , Guilvout Ingrid , Tello-Manigne Diana , Pugsley Anthony P. , Alzari Pedro M. , Pecorari Frédéric
Published: November 2007

We engineered a class of proteins that binds selected polypeptides with high specificity and affinity. Use of the protein scaffold of Sac7d, belonging to a protein family that binds various ligands, overcomes limitations inherent in the use of antibodies as intracellular inhibitors: it lacks disulfide bridges, is small and stable, and can be produced in large amounts. An
in vitro
combinatorial/selection approach generated specific, high-affinity (up to 140 pM) binders against bacterial outer membrane secretin PulD. When exported to the
Escherichia coli
periplasm, they inhibited PulD oligomerization, thereby blocking the type II secretion pathway of which PulD is part. Thus, high-affinity inhibitors of protein function can be derived from Sac7d and can be exported to, and function in, a cell compartment other than that in which they are produced.
In vitro
synthesis of the iron–molybdenum cofactor of nitrogenase from iron, sulfur, molybdenum, and homocitrate using purified proteins
Authors: Curatti Leonardo , Hernandez Jose A. , Igarashi Robert Y. , Soboh Basem , Zhao Dehua , Rubio Luis M.
Published: November 2007

Biological nitrogen fixation, the conversion of atmospheric N
2
to NH
3
, is an essential process in the global biogeochemical cycle of nitrogen that supports life on Earth. Most of the biological nitrogen fixation is catalyzed by the molybdenum nitrogenase, which contains at its active site one of the most complex metal cofactors known to date, the iron–molybdenum cofactor (FeMo-co). FeMo-co is composed of 7Fe, 9S, Mo,
R
-homocitrate, and one unidentified light atom. Here we demonstrate the complete
in vitro
synthesis of FeMo-co from Fe
2+
, S
2−
, MoO
4
2−
, and
R
-homocitrate using only purified Nif proteins. This synthesis provides direct biochemical support to the current model of FeMo-co biosynthesis. A minimal
in vitro
system, containing NifB, NifEN, and NifH proteins, together with Fe
2+
, S
2−
, MoO
4
2−
,
R
-homocitrate,
S
-adenosyl methionine, and Mg-ATP, is sufficient for the synthesis of FeMo-co and the activation of apo-dinitrogenase under anaerobic-reducing conditions. This
in vitro
system also provides a biochemical approach to further study the function of accessory proteins involved in nitrogenase maturation (as shown here for NifX and NafY). The significance of these findings in the understanding of the complete FeMo-co biosynthetic pathway and in the study of other complex Fe-S cluster biosyntheses is discussed.
Antagonistic nature of T helper 1/2 developmental programs in opposing peripheral induction of Foxp3
+
regulatory T cells
Authors: Wei Jun , Duramad Omar , Perng Olivia A. , Reiner Steven L. , Liu Yong-Jun , Qin F. Xiao-Feng
Published: November 2007

Recent studies have highlighted the importance of peripheral induction of Foxp3-expressing regulatory T cells (Tregs) in the dominant control of immunological tolerance. However, Foxp3
+
Treg differentiation from naïve CD4
+
T cells occurs only under selective conditions, whereas the classical T helper (Th) 1 and 2 effector development often dominate T cell immune responses to antigen stimulation in the periphery. The reason for such disparity remains poorly understood. Here we report that Th1/Th2-polarizing cytokines can potently inhibit Foxp3
+
Treg differentiation from naïve CD4
+
precursors induced by TGF-β. Furthermore, antigen receptor-primed CD4
+
T cells are resistant to Treg induction because of autocrine production of IFNγ and/or IL-4, whereas neutralizing IFNγ and IL-4 not only can potentiate TGF-β-mediated Foxp3 induction
in vitro
but can also enhance antigen-specific Foxp3
+
Treg differentiation
in vivo
. Mechanistically, inhibition of Foxp3
+
Treg development by Th1/Th2-polarizing cytokines involves the activation of Th1/Th2 lineage transcription factors T-bet and GATA-3 through the canonical Stat1-, Stat4-, and Stat6-dependent pathways. Using IFNγ and IL-4 knockouts and retrovirus-mediated transduction of T-bet and GATA-3, we further demonstrate that enforced expression of the Th1/Th2 lineage-specific transcription factors is sufficient to block Foxp3 induction and Treg differentiation independent of the polarizing/effector cytokines. Thus, our study has unraveled a previously unrecognized mechanism of negative cross-regulation of Foxp3
+
Treg fate choice by Th1/Th2 lineage activities. In addition, these findings also provide an attainable explanation for the general paucity of antigen-triggered
de novo
generation of Foxp3
+
Tregs in the periphery.
Magnetic field-induced assembly of oriented superlattices from maghemite nanocubes
Authors: Ahniyaz Anwar , Sakamoto Yasuhiro , Bergström Lennart
Published: November 2007

Tailoring the structure of nanocrystal superlattices is an important step toward controlled design of novel nanostructured materials and devices. We demonstrate how the long-range order and macroscopic dimensions of magnetic nanoparticle arrays can be controlled by the use of a modulated magnetic field. Inducing a dipolar attraction during the initial stage of the drying-mediated self-assembly process was sufficient to assemble the superparamagnetic oleate-capped maghemite nanocubes into large and defect-free superstructures with both translational and orientational order. The characteristic dimensions of the superlattice are controlled by the particle concentration as well as the duration of the applied magnetic field. The superparamagnetic maghemite nanocubes assemble into large and highly oriented thin arrays by applying the magnetic field perpendicular to the substrate surface only during the initial phase of drying-mediated self-assembly. Micrometer-sized and thick three-dimensional mesocrystals are obtained when the drying dispersion is subjected to an external magnetic field of moderate strength for the entire duration of the assembly process. The discovery of how translational and orientation order of nanocrystal superlattices can be induced by a temporal modulation of an anisotropic interparticle force offers new insight on the importance of the initial nucleation stage in the self-assembly process and suggests new routes for controlled self-assembly of dipolar nanocrystals.
Self-recognition and self-selection in multicomponent supramolecular coordination networks on surfaces
Authors: Langner Alexander , Tait Steven L. , Lin Nian , Rajadurai Chandrasekar , Ruben Mario , Kern Klaus
Published: November 2007

Self-recognition, self-selection, and dynamic self-organization are of fundamental importance for the assembly of all supramolecular systems, but molecular-level information is not generally accessible. We present direct examples of these critical steps by using scanning tunneling microscopy to study mixtures of complementary organic ligands on a copper substrate. The ligands coordinate cooperatively with iron atoms to form well ordered arrays of rectangular multicomponent compartments whose size and shape can be deliberately tuned by selecting ligands of desired length from complementary ligand families. We demonstrate explicitly that highly ordered supramolecular arrays can be produced from redundant ligand mixtures by molecular self-recognition and -selection, enabled by efficient error correction and cooperativity, and show an example of failed self-selection due to error tolerance in the ligand mixture, leading to a disordered structure.
Identification of xanthurenic acid 8-
O
-β-
d
-glucoside and xanthurenic acid 8-
O
-sulfate as human natriuretic hormones
Authors: Cain Christopher D. , Schroeder Frank C. , Shankel Stewart W. , Mitchnick Mark , Schmertzler Michael , Bricker Neal S.
Published: November 2007

Hormonal regulation of salt excretion and water balance by the kidneys is well documented. Before 1961, it was widely believed that the glomerular filtration rate and the steroid hormone aldosterone controlled sodium balance in the body. In 1961, deWardener
et al.
[de Wardener HE, Mills IH, Clapham WF, Hayter CJ (1961)
Clin Sci
21:249–258] showed that when these two variables were controlled, the kidney was still able to increase sodium excretion in response to a salt load. Several lines of evidence argued for a small-molecule signal as a definitive modulator of sodium excretion by the kidney. However, the chemical nature of the suspected natriuretic agent remained unknown. Here we report the identification and natriuretic activity of two closely related small molecules isolated from human urine, xanthurenic acid 8-
O
-β-
d
-glucoside and xanthurenic acid 8-
O
-sulfate. The two compounds were partially purified by activity-guided fractionation and subsequently identified by using NMR spectroscopic analyses of enriched active fractions. Both compounds caused substantial and sustained (1- to 2-h) natriuresis in rats and no or minimal concomitant potassium excretion. We believe these compounds constitute a class of kidney hormones that also could influence sodium transport in nonkidney tissues given that these tryptophan metabolites presumably represent evolutionarily old structures.