bluuebunny/crossref_metadata_2025 huggingface dataset:
Triosmium Clusters Containing 2-Mercaptobenzothiazolate Ligands
Authors: Khaleque Md. Abdul , Azam Kazi A. , Karim Md. Manzurul , Ghosh Shishir , Hogarth Graeme , Kabir Shariff E.
Published: February 2012

Reaction of the labile cluster [Os3(CO)10(NCMe)2] with 2,2′-benzothiazyl disulfide leads to the isolation of four products, namely the known hydride complex [Os3(CO)10(µ-H)(µ- S2NC7H4)], [Os3(CO)10(µ-S2NC7H4)2] (1) in which both thiolate ligands act as three-electron donor ligands and span a single osmium-osmium vector and two isomers of [Os3(CO)9(µ-S2NC7H4)(µ3-η2-S2NC7H4)] (2, 3) in which one thiolate caps a face of the triosmium cluster via secondary nitrogen coordination. In a separate experiment thermolysis of 1 in n-heptane affords only 2. Cluster 1 contains two 2-mercaptobenzothiazolate ligands in a µ-η1 mode of bonding, while 2 and 3 are isomers differing in the relative disposition of the two 2-mercaptobenzothiazolate ligands.
Australian health professionals’ social media (Web 2.0) adoption trends: early 21st century health care delivery and practice promotion
Authors: Usher Wayne T.
Published: February 2012

This study was concerned with indentifying reasons behind patterns of social media (Web 2.0) usage associated with eight of Australia’s major health professions. Attention was given to uncovering some of the more significant motivations for the resistance or adoption of Web 2.0 technologies for health care delivery and practice promotion by Australian health professionals. Surveys were developed from a common set of questions with specific variations between professions negotiated with professional health societies. Survey questions were constructed in an attempt to identify Web 2.0 adoption trends. An online survey (www.limesurvey.org) was used to collect data. Initial data preparation involved the development of one integrated SPSS file to incorporate all responses from the eight surveys undertaken. Initial data analysis applied Frequencies and Crosstabs to the identified groups and provided a profile of respondents by key business and demographic characteristics. Of the 935 respondents, 9.5% of participants indicated that they used Web 2.0 for their professional work, 19.1% of them did not use it for work but used it for their personal needs and 71.3% of them did not use Web 2.0 at all. Participants have indicated that the main reason for ‘choosing not to adopt’ Web 2.0 applications as a way of delivering health care to their patients is due to the health professionals’ lack of understanding of Web 2.0 (83.3%), while the main reason for ‘choosing to adopt’ Web 2.0 applications is the perception of Web 2.0 as a quick and effective method of communication (73.0%). This study has indicated that Australian health professionals ‘choose not to adopt’ Web 2.0 usage as a way of delivering health care primarily due to ‘a lack of understanding as to how social media would be used in health care’ (83.3%). This study identifies that Australian health professionals are interacting with Web 2.0 technologies in their private lives but are failing to see how such technologies might be used throughout their professions. Australian health professionals are willing to undertake online educational courses (n = 553, 58%) designed to upskill them about how Web 2.0 may be used for practice promotion and health care delivery.
Electrical resistivity and thermal conductivity of liquid Fe alloys at high
P
and
T
, and heat flux in Earth’s core
Authors: de Koker Nico , Steinle-Neumann Gerd , Vlček Vojtěch
Published: February 2012

Earth’s magnetic field is sustained by magnetohydrodynamic convection within the metallic liquid core. In a thermally advecting core, the fraction of heat available to drive the geodynamo is reduced by heat conducted along the core geotherm, which depends sensitively on the thermal conductivity of liquid iron and its alloys with candidate light elements. The thermal conductivity for Earth’s core is very poorly constrained, with current estimates based on a set of scaling relations that were not previously tested at high pressures. We perform first-principles electronic structure computations to determine the thermal conductivity and electrical resistivity for Fe, Fe–Si, and Fe–O liquid alloys. Computed resistivity agrees very well with existing shock compression measurements and shows strong dependence on light element concentration and type. Thermal conductivity at pressure and temperature conditions characteristic of Earth’s core is higher than previous extrapolations. Conductive heat flux near the core–mantle boundary is comparable to estimates of the total heat flux from the core but decreases with depth, so that thermally driven flow would be constrained to greater depths in the absence of an inner core.
Cellulose microfibril crystallinity is reduced by mutating C-terminal transmembrane region residues CESA1
A903V
and CESA3
T942I
of cellulose synthase
Authors: Harris Darby M. , Corbin Kendall , Wang Tuo , Gutierrez Ryan , Bertolo Ana L. , Petti Carloalberto , Smilgies Detlef-M. , Estevez José Manuel , Bonetta Dario , Urbanowicz Breeanna R. , Ehrhardt David W. , Somerville Chris R. , Rose Jocelyn K. C. , Hong Mei , DeBolt Seth
Published: February 2012

The mechanisms underlying the biosynthesis of cellulose in plants are complex and still poorly understood. A central question concerns the mechanism of microfibril structure and how this is linked to the catalytic polymerization action of cellulose synthase (CESA). Furthermore, it remains unclear whether modification of cellulose microfibril structure can be achieved genetically, which could be transformative in a bio-based economy. To explore these processes
in planta
, we developed a chemical genetic toolbox of pharmacological inhibitors and corresponding resistance-conferring point mutations in the C-terminal transmembrane domain region of CESA1
A903V
and CESA3
T942I
in
Arabidopsis thaliana
. Using
13
C solid-state nuclear magnetic resonance spectroscopy and X-ray diffraction, we show that the cellulose microfibrils displayed reduced width and an additional cellulose C4 peak indicative of a degree of crystallinity that is intermediate between the surface and interior glucans of wild type, suggesting a difference in glucan chain association during microfibril formation. Consistent with measurements of lower microfibril crystallinity, cellulose extracts from mutated CESA1
A903V
and CESA3
T942I
displayed greater saccharification efficiency than wild type. Using live-cell imaging to track fluorescently labeled CESA, we found that these mutants show increased CESA velocities in the plasma membrane, an indication of increased polymerization rate. Collectively, these data suggest that CESA1
A903V
and CESA3
T942I
have modified microfibril structure in terms of crystallinity and suggest that in plants, as in bacteria, crystallization biophysically limits polymerization.
Contrasting Maturation and Growth of Northern Rock Sole in the Eastern Bering Sea and Gulf of Alaska for the Purpose of Stock Management
Authors: Stark James W.
Published: February 2012

The primary purpose of this study was to provide commercial fishery managers with the age- and length-at-maturity information about northern rock sole Lepidopsetta polyxystra needed for them to set a sustainable overfishing limit and evaluate the precision of the two predictors of maturity. The estimated length at which 50% of eastern Bering Sea female northern rock sole matured (L  50) was 309 mm, which was significantly smaller than that for Gulf of Alaska females. We determined that the differences in L  50 between populations were probably the result of differences in the rate of female growth. Growth was significantly faster in the Gulf of Alaska than in the eastern Bering Sea during 1996 and 1999. However, by 2007 the growth rates were similar between these areas. The variability in growth was correlated with seawater temperature. There were also differences in the age at which 50% of the females matured (A  50) between the populations in the eastern Bering Sea (9 years) and the Gulf of Alaska (7 years). In contrast, within the eastern Bering Sea, females maintained a similar A  50 over several years, which indicates that age is the most reliable predictor of maturity for northern rock sole.

Received April 8, 2011; accepted August 11, 2011
A Method to Train Groups of Predator-Naive Fish to Recognize and Respond to Predators When Released into the Natural Environment
Authors: Olson Justin A. , Olson Jenae M. , Walsh Rachel E. , Wisenden Brian D.
Published: February 2012

Hatcheries are effective at producing large numbers of fish for augmenting fisheries or conserving endangered populations, but the fish they produce are often predator-naive, resulting in high levels of predation mortality when the fish are first released into natural water bodies. Fish normally acquire recognition of novel stimuli as indicators of danger when injury-released chemical cues from conspecifics (a known indicator of an actively foraging predator) are presented simultaneously with a novel stimulus (e.g., predator odor, image). Thus, fish in wild populations quickly learn the sight and smell of their predators. Past research has demonstrated that predator-naive, hatchery-reared fish can be trained to recognize predators and that fish trained by this method have a significantly greater probability of surviving an encounter with a predator. To implement predator training in fishery management, predator recognition training must be feasible on a large scale in a way that does not place an undue financial or logistical burden on fisheries managers. Here, we demonstrate that groups of fish can be quickly and easily conditioned to recognize the odor of a novel predator and react to it with antipredator behavior. This simple method could improve the cost effectiveness of any stocking program, result in greater densities of managed stocks, and enhance the direct and indirect economic benefits of a fishery.

Received April 21, 2011; accepted October 11, 2011
Influence of gender and types of sports training on QT variables in young elite athletes
Authors: Omiya Kazuto , Sekizuka Hiromitsu , Kida Keisuke , Suzuki Kengo , Akashi Yoshihiro J. , Ohba Haruo , Musha Haruki
Published: February 2012

Influence of gender and sports training on QT variables such as QT interval and dispersion (QT dispersion: QTD) in young elite athletes were evaluated. Subjects included 104 male and 97 female Japanese elite athletes (mean age 21.6 years). Sports included basketball, fencing, gymnastics, judo, swimming, tennis, track and field and volleyball. Age‐matched healthy non‐athletes (32 men and 20 women) were enrolled as controls. QT measurements were manually obtained from a 12‐lead resting electrocardiogram and QTD was calculated as the difference between the longest and shortest QT intervals. A corrected QT interval (QTc) was obtained using Bazett's formula. Subjects were divided into two groups; an endurance training group and a static training group on the basis of their training types. Results: Maximum and minimum QTc were significantly longer in female athletes than in male athletes (max: 414.2 vs. 404.5 ms, min: 375.1 vs. 359.2 ms, p<0.0001 respectively), whereas QTc dispersion (QTcD) was shorter in female athletes than in male athletes (39.2 vs. 45.3 ms, p<0.0001). QTcD was significantly shorter in female athletes than in the female control group (39.2 vs. 45.2 ms, p<0.05). However, no statistically significant difference was observed between male athletes and the male control group. Male gymnasts exhibited significantly longer QTcD than the control group (p<0.01), but female gymnasts had significantly shorter QTcD than the control group (p<0.05). Maximum QTc intervals were prolonged in the male static training group compared with non‐athletes, and QTcDs in the static training group were prolonged compared with the endurance training group. However, no significant difference was observed in the female group. In conclusion, both gender and different characteristics of sports training may affect QT variables even in young elite athletes. Vigorous static exercise training may independently prolong QT variables.
Intraflagellar transport—the “new motility” 20 years later
Authors: Kozminski Keith G.
Published: February 2012

Intraflagellar transport is the rapid, bidirectional movement of protein complexes along the length of most eukaryotic cilia and flagella. Discovery of this intracellular process in Chlamydomonas reinhardtii 20 years ago led to a rapid discovery of cellular mechanisms that underlie a large number of human ciliopathies. Described herein are the events that led to this discovery.
Cucumis melo MicroRNA Expression Profile During Aphid Herbivory in a Resistant and Susceptible Interaction
Authors: Sattar Sampurna , Song Yan , Anstead James A. , Sunkar Ramanjulu , Thompson Gary A.
Published: February 2012

Aphis gossypii resistance in melon (Cucumis melo) is due to the presence of a single dominant virus aphid transmission (Vat) gene belonging to the nucleotide-binding site leucine-rich repeat family of resistance genes. Significant transcriptional reprogramming occurs in Vat+ plants during aphid infestation as metabolism shifts to respond to this biotic stress. MicroRNAs (miRNAs) are involved in the regulation of many biotic stress responses. The role of miRNAs was investigated in response to aphid herbivory during both resistant and susceptible interactions. Small RNA (smRNA) libraries were constructed from bulked leaf tissues of a Vat+ melon line following early and late aphid infestations. Sequence analysis indicated that the expression profiles of conserved and newly identified miRNAs were altered during different stages of aphid herbivory. These results were verified by quantitative polymerase chain reaction experiments in both resistant Vat+ and susceptible Vat– interactions. The comparative analyses revealed that most of the conserved miRNA families were differentially regulated during the early stages of aphid infestation in the resistant and susceptible interactions. Along with the conserved miRNA families, 18 cucurbit-specific miRNAs were expressed during the different stages of aphid herbivory. The comparison of the miRNA profiles in the resistant and susceptible interactions provides insight into the miRNA-dependent post-transcriptional gene regulation in Vat-mediated resistance.
Pseudomonas fluorescensInduces Strain-Dependent and Strain-Independent Host Plant Responses in Defense Networks, Primary Metabolism, Photosynthesis, and Fitness
Authors: Weston David J. , Pelletier Dale A. , Morrell-Falvey Jennifer L. , Tschaplinski Timothy J. , Jawdy Sara S. , Lu Tse-Yuan , Allen Sara M. , Melton Sarah J. , Martin Madhavi Z. , Schadt Christopher W. , Karve Abhijit A. , Chen Jin-Gui , Yang Xiaohan , Doktycz Mitchel J. , Tuskan Gerald A.
Published: February 2012

Colonization of plants by nonpathogenic Pseudomonas fluorescens strains can confer enhanced defense capacity against a broad spectrum of pathogens. Few studies, however, have linked defense pathway regulation to primary metabolism and physiology. In this study, physiological data, metabolites, and transcript profiles are integrated to elucidate how molecular networks initiated at the root–microbe interface influence shoot metabolism and whole-plant performance. Experiments with Arabidopsis thaliana were performed using the newly identified P. fluorescens GM30 or P. fluorescens Pf-5 strains. Co-expression networks indicated that Pf-5 and GM30 induced a subnetwork specific to roots enriched for genes participating in RNA regulation, protein degradation, and hormonal metabolism. In contrast, only GM30 induced a subnetwork enriched for calcium signaling, sugar and nutrient signaling, and auxin metabolism, suggesting strain dependence in network architecture. In addition, one subnetwork present in shoots was enriched for genes in secondary metabolism, photosynthetic light reactions, and hormone metabolism. Metabolite analysis indicated that this network initiated changes in carbohydrate and amino acid metabolism. Consistent with this, we observed strain-specific responses in tryptophan and phenylalanine abundance. Both strains reduced host plant carbon gain and fitness, yet provided a clear fitness benefit when plants were challenged with the pathogen P. syringae DC3000.
First Report of Anthracnose Caused by Colletotrichum gloeosporioides on Malus prunifolia in Korea
Authors: Cheon W. , Kim Y. S. , Jeon Y. H.
Published: February 2012

In 2010 and 2011, crab apples in Andong Province, Korea were found with dark brown spots on the fruit and mummified fruit on a tree. The fruit surface had red, circular spots that contained smaller, white spots; the color of the inner spots later changed to brown or black. Eventually, the rotten fruit dried and became mummified. Microscopic examination revealed the presence of acervuli and dark brown-to-black, needle-shaped setae. To isolate potential pathogens from infected fruit, small sections (5 to 10 mm2) were excised from the margins of lesions. These sections were surface sterilized with 70% ethanol and 1% NaOCl for 1 min and then rinsed three times with sterile distilled water. The fungus that was isolated produced whitish mycelia when grown on potato dextrose agar (PDA); the mycelia later became gray to dark gray with aerial mycelia in tufts and numerous conidia were produced. The conidia were straight, cylindrical with an obtuse apex and a truncated base, and measured 11.4 to 17.5 × 4.2 to 7.1 μm. The measurements and taxonomic characteristics coincide with those of Colletotrichum gloeosporioides (Penz.) (1). The isolated fungus was tested for pathogenicity on crab apples and cv. Fuji apples by inoculation with a conidial suspension (105 conidia/ml) prepared from 20-day-old PDA cultures. A 20-μl drop of the conidial suspension was placed onto crab apple and apple fruits that had been wounded by piercing them 1 to 2 mm deep with a pin. Small, dark lesions were observed on the artificially inoculated fruit 3 days after inoculation. Nine days after inoculation, dark lesions with salmon-colored masses of conidia were observed on fruit, which were also soft and sunken. Abundant masses of conidia were produced in the decayed tissues. The fungus was reisolated from the parts of the fruits showing the symptoms. The internal transcribed spacer (ITS) rDNA of the isolated fungus was amplified and sequenced by PCR as described by White et al. (2). The resulting 582-bp of ITS rDNA sequence was deposited in GenBank (Accession No. JQ405742). A BLAST analysis for sequence similarity of the ITS region revealed 100% identity with nucleotide sequences for C. gloeosporioides isolates (Accession Nos. HQ645080 and AB458667). The results obtained on morphological characteristics, pathogenicity, and molecular data corresponded with those of C. gloeosporioides described by Sutton (1). To our knowledge, this is the first report of the presence of C. gloeosporioides on crab apple in Korea (3). Crab apple is used as a pollinator for single-cultivar apple orchards and may become a possible source of inoculum for cultivated apple.

References: (1) T. B. Sutton. Compendium of Apple and Pear Diseases. The American Phytopathological Society, St. Paul, MN, 1990. (2) T. J. White et al. PCR Protocols: A Guide to Methods and Applications, Academic Press, Inc., New York, 1990. (3) S. H. Yu. List of Plant Diseases in Korea. 5th ed. (in Korean). The Korean Society of Plant Pathology, 2009.
Comprehensive Evaluation of Virulence and Resistance Data: A New Analysis Tool
Authors: Schachtel Gabriel A. , Dinoor Amos , Herrmann Antje , Kosman Evsey
Published: February 2012

The functioning and features of the new software package VAT (Virulence Analysis Tool) are introduced. VAT provides a range of methods for the analysis of plant pathosystems. The techniques are applicable to other binary data sets that are organized in large two-way tables, e.g., molecular marker data. The main features are data entry, descriptive tools, and inference statistics by resampling. About 50 well-established or newly developed indices allow a detailed diversity analysis of sexually and asexually reproducing populations. VAT facilitates a comprehensive, effective, and logically consistent evaluation and presentation of virulence and resistance data. A translation option simplifies the comparison of results from differently coded pathotypes. The software package comes with a detailed manual and is freely available on the internet at tau.ac.il/lifesci/departments/plant_s/members/kosman/VAT.html and at va-tipp.de .
First Report of the Lesion Nematode, Pratylenchus agilis, Parasitizing Wheat in China
Authors: Wang Z. Y. , Shi Y. , Li H. L. , Zhang M.
Published: February 2012

Wheat (Triticum aestivum L.) fields in Zhengzhou, Henan Province that exhibited reduced height and number of tillers were surveyed in 2008, and samples were collected for analyses. Fifteen of thirty-five samples contained a nematode suspected of causing small, brown lesions in roots. Both lateral roots and root hairs were reduced in infected plants. Nematode presence was associated with enlarging lesions and necrotic roots. We also observed lesion nematode infestation in samples with no symptoms in the roots. During the growing season, wheat yield increased by 14% with nematocide treatments in Zhengzhou suburb fields. The morphological and molecular analyses of the nematodes isolated from soil samples established the identity of the species as the lesion nematode, Pratylenchus agilis (2,3). Morphological characteristics that were used for identification included female body, lip annules, tail terminus, number of lines in the lateral field, stylet knobs, stylet length, and vulva location in relation to body length. Females were cylindrical, measured 452 to 811 μm long, and contained two lip annules, a smooth tail terminus, four lateral lines, a vulva at 72.64 to 79.97%, a stylet of 16.20 to 17.55 μm, basal esophageal lobes elongated less than twice the body width, and stylet knobs rounded posteriorly. Males were rare and the spermatheca was empty. Molecular analysis was conducted by amplifying the internal transcribed spacer (ITS) regions ITS1 and 2. Sequence of ITS regions from this population (GenBank Accession No. JQ039330) showed highest sequence homology to P. agilis isolate PagKL5 (GenBank Accession No. FJ71289.1) with the identity of 90%. High variability at species level has been found for Pratylenchus species (1). On the basis of the morphological traits and molecular analyses, the nematodes were identified as P. agilis. To our knowledge, this is the first report of P. agilis parasitizing wheat.

References: (1) F. De Luca et al. Eur. J. Plant Pathol. 130:415, 2011. (2) A. M. Golden et al. Plant Dis. Rep. 62:430, 1978. (3) R. V. Rebois et al. J. Nematol. 18:392, 1986.
Severe Outbreak of Rust Caused by Coleosporium pulsatillae Detected on Pulsatilla spp. in China
Authors: Su D. , Fu J. F. , Zhou R. J. , Yan X. R.
Published: February 2012

Windflower (Pulsatilla spp.) is a perennial medicinal plant in the Ranunculaceae with high economic value as well as medicinal value in China. It is a commonly used Chinese herbal medicine. In 2007, two species, Pulsatilla koreana Nakai and P. chinensis Regel, were observed with severe rust symptoms at three locations (Shenyang City, Benxi City, and Fushun County) in Liaoning, China. The diseased area was estimated to be more than 500 ha and the yield was reduced by 30% on average with up to 65% yield losses in some fields. Since its first record in 2007, the disease has been recorded every year in parts of China. A survey of all cultivated fields in August 2011 revealed that 90% of the Pulsatilla plants were heavily infected with rust. Early symptoms on the adaxial leaf surfaces were small, circular, yellow spots that later enlarged, coalesced, and developed necrotic centers. On the abaxial side, numerous yellow rust uredinia were visible. Urediniospores are globose or ellipsoidal, sometimes angular in shape, with a yellowish content, and measured 22.6 to 39.4 × 15.2 to 23.9 μm. Spore walls were coarsely verrucose when examined by light and scanning electron microscopy. Telia and teliospores were observed in mid-August. Hypophyllous telia often formed around uredinial clusters. Telia were 0.3 to 1.1 mm wide and erumpent with numerous teliospores in a compact layer. Teliospores were clavate, oblong to ellipsoidal, 60.2 to 120.8 × 12.1 to 24.4 μm, gelatinous, and one celled. Teliospores were four celled with the division of the protoplast into an internal four-celled basidium. Pathogenicity tests included inoculation of young P. koreana plants by spraying a urediniospore suspension (30,000 spores/ml of deionized water). Inoculated plants were incubated at 25°C for 48 h, and typical rust symptoms and uredinia developed in 10 to 15 days. On the basis of symptomatology, the host, and morphology of uredinial and telia, the fungus was identified as Coleosporium pulsatillae (Str.) Lév (2). The internal transcribed spacer (ITS) region was amplified using ITS1-F and ITS4-B primers (3), and an amplified product of 817 bp, specific for the species C. pulsatillae, was obtained. The sequence was deposited in GenBank (Accession No. JQ029765). Although this pathogen has been mentioned as part of a fungal species survey from China, it was not fully described (4). This pathogen has been reported on Anemone chinensis in Austria, Sibiria (2), and Korea (1). It has not been reported from anywhere else in China. To our knowledge, this is the first fully described record and most severe outbreak of C. pulsatillae on windflower.

References: (1) W. D. Cho and H. D. Shin. List of Plant Diseases in Korea. Korean Society of Plant Pathology, Seoul, Korea, 2004. (2) J. B. De-Toni. Sylloge Fungorum 7:754, 1888. (3) M. Gardes et al. Mol. Ecol. 2:113, 1993. (4) F. L. Tai. Sylloge Fungorum Sinicorum. Science Press, Beijing, 1979.
Control of Xiphinema index Populations by Fallow Plants Under Greenhouse and Field Conditions
Authors: Villate Laure , Morin Elisa , Demangeat Gérard , Van Helden Maarten , Esmenjaud Daniel
Published: February 2012

The dagger nematode Xiphinema index has a high economic impact in vineyards by direct pathogenicity and above all by transmitting the Grapevine fanleaf virus (GFLV). Agrochemicals have been largely employed to restrict the spread of GFLV by reducing X. index populations but are now banned. As an alternative to nematicides, the use of fallow plants between two successive vine crops was assessed. We selected plant species adapted to vineyard soils and exhibiting negative impact on nematodes and we evaluated their antagonistic effect on X. index in greenhouse using artificially infested soil, and in naturally infested vineyard conditions. The screening was conducted with plants belonging to the families Asteraceae (sunflower, marigold, zinnia, and nyjer), Poaceae (sorghum and rye), Fabaceae (white lupin, white melilot, hairy vetch, and alfalfa), Brassicaceae (rapeseed and camelina), and Boraginaceae (phacelia). In the greenhouse controlled assay, white lupin, nyjer, and marigold significantly reduced X. index populations compared with that of bare soil. The vineyard assay, designed to take into account the aggregative pattern of X. index distribution, revealed that marigold and hairy vetch are good candidates as cover crops to reduce X. index populations in vineyard. Moreover, this original experimental design could be applied to manage other soilborne pathogens.
Estimating maximum bite performance in
Tyrannosaurus rex
using multi-body dynamics
Authors: Bates K. T. , Falkingham P. L.
Published: February 2012

Bite mechanics and feeding behaviour in
Tyrannosaurus rex
are controversial. Some contend that a modest bite mechanically limited
T. rex
to scavenging, while others argue that high bite forces facilitated a predatory mode of life. We use dynamic musculoskeletal models to simulate maximal biting in
T. rex
. Models predict that adult
T. rex
generated sustained bite forces of 35 000–57 000 N at a single posterior tooth, by far the highest bite forces estimated for any terrestrial animal. Scaling analyses suggest that adult
T. rex
had a strong bite for its body size, and that bite performance increased allometrically during ontogeny. Positive allometry in bite performance during growth may have facilitated an ontogenetic change in feeding behaviour in
T. rex
, associated with an expansion of prey range in adults to include the largest contemporaneous animals.
General theory of geometric Lévy models for dynamic asset pricing
Authors: Brody Dorje C. , Hughston Lane P. , Mackie Ewan
Published: February 2012

The geometric Lévy model (GLM) is a natural generalization of the geometric Brownian motion (GBM) model used in the derivation of the Black–Scholes formula. The theory of such models simplifies considerably if one takes a pricing kernel approach. In one dimension, once the underlying Lévy process has been specified, the GLM has four parameters: the initial price, the interest rate, the volatility and the risk aversion. The pricing kernel is the product of a discount factor and a risk aversion martingale. For GBM, the risk aversion parameter is the market price of risk. For a GLM, this interpretation is not valid: the excess rate of return is a nonlinear function of the volatility and the risk aversion. It is shown that for positive volatility and risk aversion, the excess rate of return above the interest rate is positive, and is increasing with respect to these variables. In the case of foreign exchange, Siegel's paradox implies that one can construct foreign exchange models for which the excess rate of return is positive for both the exchange rate and the inverse exchange rate. This condition is shown to hold for any geometric Lévy model for foreign exchange in which volatility exceeds risk aversion.
Bottlenose dolphins exchange signature whistles when meeting at sea
Authors: Quick Nicola J. , Janik Vincent M.
Published: February 2012

The bottlenose dolphin,Tursiops truncatus, is one of very few animals that, through vocal learning, can invent novel acoustic signals and copy whistles of conspecifics. Furthermore, receivers can extract identity information from the invented part of whistles. In captivity, dolphins use such signature whistles while separated from the rest of their group. However, little is known about how they use them at sea. If signature whistles are the main vehicle to transmit identity information, then dolphins should exchange these whistles in contexts where groups or individuals join. We used passive acoustic localization during focal boat follows to observe signature whistle use in the wild. We found that stereotypic whistle exchanges occurred primarily when groups of dolphins met and joined at sea. A sequence analysis verified that most of the whistles used during joins were signature whistles. Whistle matching or copying was not observed in any of the joins. The data show that signature whistle exchanges are a significant part of a greeting sequence that allows dolphins to identify conspecifics when encountering them in the wild.
Brilliant camouflage
: photonic crystals in the diamond weevil,
Entimus imperialis
Authors: Wilts Bodo D. , Michielsen Kristel , Kuipers Jeroen , De Raedt Hans , Stavenga Doekele G.
Published: February 2012

The neotropical diamond weevil,
Entimus imperialis
, is marked by rows of brilliant spots on the overall black elytra. The spots are concave pits with intricate patterns of structural-coloured scales, consisting of large domains of three-dimensional photonic crystals that have a diamond-type structure. Reflectance spectra measured from individual scale domains perfectly match model spectra, calculated with anatomical data and finite-difference time-domain methods. The reflections of single domains are extremely directional (observed with a point source less than 5°), but the special arrangement of the scales in the concave pits significantly broadens the angular distribution of the reflections. The resulting virtually angle-independent green coloration of the weevil closely approximates the colour of a foliaceous background. While the close-distance colourful shininess of
E. imperialis
may facilitate intersexual recognition, the diffuse green reflectance of the elytra when seen at long-distance provides cryptic camouflage.
Iron starvation regulates the type III secretion system in Bordetella bronchiseptica
Authors: Kurushima Jun , Kuwae Asaomi , Abe Akio
Published: February 2012

The type III secretion system (T3SS) plays a key role in the exertion of full virulence by Bordetella bronchiseptica. However, little is known about the environmental stimuli that induce expression of T3SS genes. Here, it is reported that iron starvation is a signal for T3SS gene expression in B. bronchiseptica. It was found that, when B. bronchiseptica is cultured under iron‐depleted conditions, secretion of type III secreted proteins is greater than that in bacteria grown under iron‐replete conditions. Furthermore, it was confirmed that induction of T3SS‐dependent host cell cytotoxicity and hemolytic activity is greatly enhanced by infection with iron‐depleted Bordetella. In contrast, production of filamentous hemagglutinin is reduced in iron‐depleted Bordetella. Thus, B. bronchiseptica controls the expression of virulence genes in response to iron starvation.
Endoscopic evaluation of the gastro‐duodenal tolerance of short‐term analgesic treatment with 25 mg diclofenac‐K liquid capsules
Authors: Hawkey C. , Burnett I. , Gold M. S. , Garsed K. , Stevenson D. , Mannath J. , Norman A. , Shepherd V. , Subramanian V. , Johnston R. D. , Brown M.
Published: February 2012

Background

Diclofenac‐potassium (diclofenac‐‐K) 25 mg liquid capsule is absorbed more quickly than the tablet formulation. It offers potential for rapid pain relief, but may alter gastro‐duodenal tolerability.

Aim

To evaluate the gastro‐duodenal tolerance of diclofenac‐K 25 mg liquid capsules vs. diclofenac‐K 12.5 mg tablets, acetylsalicylic acid (ASA) 500 mg tablets and ibuprofen 200 mg liquid capsules.

Methods

In an endoscopist‐blinded, randomised, parallel‐group study, volunteers received 15 doses of diclofenac‐K 25 mg liquid capsules (n = 36), diclofenac‐K 2 × 12.5 mg tablets (n = 36), ibuprofen 2 × 200 mg liquid capsules (n = 24) or ASA 2 × 500 mg tablets (n = 36) over 5 days. The primary outcome was the incidence of erosive gastro‐duodenal lesions at Day 6. Secondary outcomes included modified Lanza score and change in gastric mucosal prostaglandin synthesis.

Results

The lowest incidence of erosive gastro‐duodenal lesions was with diclofenac‐K liquid capsules (53%), compared to 61% with diclofenac‐K tablets (P = 0.52), 75% with ibuprofen (P = 0.08) and 94% with ASA (P = 0.001). Results were similar for the Lanza scores, although diclofenac‐K liquid capsules were significantly superior to ibuprofen liquid capsules (P = 0.04). Diclofenac‐K liquid capsules inhibited prostaglandin synthesis by 52% compared to 64% for diclofenac‐K tablets (P = 0.10), 50% for ibuprofen (P = 0.85) and 79% for ASA (P = 0.002). With respect to safety, adverse events were most frequent in the ASA group, predominantly gastrointestinal events.

Conclusions

Mucosal injury with diclofenac‐K liquid 25 mg liquid capsules was similar to diclofenac‐K 25 mg tablets, significantly lower than ASA 1 g tablets and showed some superiority over ibuprofen 400 mg liquid capsules (EudraCT Number 2009‐011278‐14).
Changes in the herbage nutritive value and yield associated with threshold responses of vegetation to grazing in Mongolian rangelands
Authors: Sasaki T. , Ohkuro T. , Jamsran U. , Takeuchi K.
Published: February 2012

We examined the changes in the nutritive value and yield of herbage along a grazing gradient, where abrupt changes in community composition occurred, at multiple ecological sites in Mongolian rangelands. At grassland sites, changes in the herbage nutritive value could be attributed to rapid replacement of perennial grasses or forbs with weedy annual forbs along a grazing gradient. Crude protein (CP) concentration increased sharply in approaching the source of grazing gradient, whereas neutral detergent fibre and metabolizable energy (ME) concentrations decreased sharply. As ME can be utilized as a main index of herbage nutritive value, these results indicated its overall loss with severe grazing. Consequently, gradual increases in the yields of CP and ME in the direction of the gradient source at the grassland sites did not necessarily indicate the improvement of rangeland condition. In contrast, at shrubland sites, we could not generally detect any significant trends in the herbage nutritive value. The yield of ME gradually decreased in the direction of gradient source, suggesting that grazing affects herbage yield rather than herbage feed value at shrubland sites. Thus, the nutritive value and yield of herbage can be modified greatly in association with nonlinear responses of vegetation to livestock grazing.
Oxytocin and Vasopressin Agonists and Antagonists as Research Tools and Potential Therapeutics
Authors: Manning M. , Misicka A. , Olma A. , Bankowski K. , Stoev S. , Chini B. , Durroux T. , Mouillac B. , Corbani M. , Guillon G.
Published: February 2012

We recently reviewed the status of peptide and nonpeptide agonists and antagonists for the V1a, V1b and V2 receptors for arginine vasopressin (AVP) and the oxytocin receptor for oxytocin (OT). In the present review, we update the status of peptides and nonpeptides as: (i) research tools and (ii) therapeutic agents. We also present our recent findings on the design of fluorescent ligands for V1b receptor localisation and for OT receptor dimerisation. We note the exciting discoveries regarding two novel naturally occurring analogues of OT. Recent reports of a selective VP V1a agonist and a selective OT agonist point to the continued therapeutic potential of peptides in this field. To date, only two nonpeptides, the V2/V1a antagonist, conivaptan and the V2 antagonist tolvaptan have received Food and Drug Administration approval for clinical use. The development of nonpeptide AVP V1a, V1b and V2 antagonists and OT agonists and antagonists has recently been abandoned by Merck, Sanofi and Pfizer. A promising OT antagonist, Retosiban, developed at Glaxo SmithKline is currently in a Phase II clinical trial for the prevention of premature labour. A number of the nonpeptide ligands that were not successful in clinical trials are proving to be valuable as research tools. Peptide agonists and antagonists continue to be very widely used as research tools in this field. In this regard, we present receptor data on some of the most widely used peptide and nonpeptide ligands, as a guide for their use, especially with regard to receptor selectivity and species differences.
Same old Salmo? Changes in life history and demographic trends of North Iberian salmonids since the Upper Palaeolithic as revealed by archaeological remains and beast analyses
Authors: TURRERO P. , HORREO J. L. , GARCIA‐VAZQUEZ E.
Published: February 2012

Life history traits determine fitness and hence the ability of populations and species to survive through adverse conditions. Therefore, identifying temporal changes in life history traits over large timescales is necessary to understand and predict the effect of current global change on wild populations. In this study, we compare life history traits between Palaeolithic and present‐day vertebrates, analysing the number of winters spent in the river and at sea by North Iberian salmonids (Salmo salar and Salmo trutta) from two separate time frames: the Upper Palaeolithic, based on archaeological remains, and the present day, based on sport catches. The river stage did not change significantly, but the marine period has been shortened in modern anadromous specimens, accordingly shortening mean generation time. Population growth rates have been estimated through Bayesian analyses of the mitochondrial DNA control region of modern specimens for the two Salmo species using two different mutation rates (1% and 3.6%). Coincidence of coalescent Ne estimates with independent Ne calculated from catches suggests that the 3.6% mutation rate fits better the evolution of the studied populations. Population growth rate declines would have occurred in the last millennium and could be explained by a combination of climatic events and anthropogenic activities.
A glycine betaine importer limits Salmonella stress resistance and tissue colonization by reducing trehalose production
Authors: Pilonieta M. Carolina , Nagy Toni A. , Jorgensen Dana R. , Detweiler Corrella S.
Published: February 2012

Mechanisms by which Salmonella establish chronic infections are not well understood. Microbes respond to stress by importing or producing compatible solutes, small molecules that stabilize proteins and lipids. The Salmonella locus opuABCD (also called OpuC) encodes a predicted importer of the compatible solute glycine betaine. Under stress conditions, if glycine betaine cannot be imported, Salmonella enterica produce the disaccharide trehalose, a highly effective compatible solute. We demonstrate that strains lacking opuABCD accumulate more trehalose under stress conditions than wild‐type strains. ΔopuABCD mutant strains are more resistant to high‐salt, low‐pH and ‐hydrogen peroxide, conditions that mimic aspects of innate immunity, in a trehalose‐dependent manner. In addition, ΔopuABCD mutant strains require the trehalose production genes to out‐compete wild‐type strains in mice and macrophages. These data suggest that in the absence of opuABCD, trehalose accumulation increases bacterial resistance to stress in broth and mice. Thus, opuABCD reduces bacterial colonization via a mechanism that limits trehalose production. Mechanisms by which microbes limit disease may reveal novel pathways as therapeutic targets.
The de novo and salvage pathways of GDP‐mannose biosynthesis are both sufficient for the growth of bloodstream‐form Trypanosoma brucei
Authors: Kuettel Sabine , Wadum Majken C. T. , Güther Maria Lucia S. , Mariño Karina , Riemer Carolin , Ferguson Michael A. J.
Published: February 2012

The sugar nucleotide GDP‐mannose is essential for Trypanosoma brucei. Phosphomannose isomerase occupies a key position on the de novo pathway to GDP‐mannose from glucose, just before intersection with the salvage pathway from free mannose. We identified the parasite phosphomannose isomerase gene, confirmed that it encodes phosphomannose isomerase activity and localized the endogenous enzyme to the glycosome. We also created a bloodstream‐form conditional null mutant of phosphomannose isomerase to assess the relative roles of the de novo and salvage pathways of GDP‐mannose biosynthesis. Phosphomannose isomerase was found to be essential for parasite growth. However, supplementation of the medium with low concentrations of mannose, including that found in human plasma, relieved this dependence. Therefore, we do not consider phosphomannose isomerase to be a viable drug target. We further established culture conditions where we can control glucose and mannose concentrations and perform steady‐state [U‐13C]‐d‐glucose labelling. Analysis of the isotopic sugar composition of the parasites variant surface glycoprotein synthesized in cells incubated in 5 mM [U‐13C]‐d‐glucose in the presence and absence of unlabelled mannose showed that, under physiological conditions, about 80% of GDP‐mannose synthesis comes from the de novo pathway and 20% from the salvage pathway.
Balearic archipelago: three islands, three beta‐thalassemia population patterns
Authors: López‐Escribano H , Parera MM , Guix P , Serra JM , Gutierrez A , Balsells D , Oliva‐Berini E , Castro JA , Ramon MM , Picornell A
Published: February 2012

López‐Escribano H, Parera MM, Guix P, Serra JM, Gutierrez A, Balsells D, Oliva‐Berini E, Castro JA, Ramon MM, Picornell A. Balearic archipelago: three islands, three beta‐thalassemia population patterns.

The mutation spectrum of 175 β‐thalassemia (β‐thal) carriers, identified in pilot carrier screening on 22,713 individuals from Balearic Islands (Spain), is reported. The β0 CD39 (C>T) mutation is the most frequent (61.1%), followed by β+ IVS‐I‐110 (G>A) (12.0%), β+ IVS‐I‐6 (T>C) and β0 IVS‐1‐1 (G>A) (3.4% both) and eight other rare mutations (2.9–0.6%); with a distinct prevalence and distribution between islands. Minorca shows the highest prevalence in Iberian populations, with a single mutation, CD39 (C>T), present in most β‐thal carriers. Ibiza is the only Western Mediterranean population where the most frequent β‐thal mutation is IVS‐I‐110 (G>A). These results can be explained by a combination of historical–demographic characteristics together with evolutionary forces such as founder effect, genetic drift and probably selection by malaria. Knowledge of the mutational spectrum in the Balearic Islands will enable to optimize mutation detection strategy for genetic diagnosis of β‐thal in these islands.
Immune reconstitution to cytomegalovirus following partially matched‐related donor transplantation: impact of in vivo T‐cell depletion and granulocyte colony‐stimulating factor‐primed peripheral blood/bone marrow mixed grafts
Authors: Luo X.‐H. , Huang X.‐J. , Li D. , Liu K.‐Y. , Xu L.‐P. , Liu D.‐H.
Published: February 2012

Cytomegalovirus (CMV) infection and delayed immune reconstitution remains a serious obstacle for successful partially matched‐related donor transplantation (PMRD). We evaluated 42 patients for the development of CMV‐specific CD8+ T lymphocytes (CTLCMV) following granulocyte colony‐stimulating factor‐primed peripheral blood (PB) and bone marrow (BM) with anti‐thymocyte globulin (ATG)‐based PMRD. PMRD recipients achieved a high frequency, proliferation capacity, and interferon‐γ response of CTLCMV at 1 year post transplantation. CTLCMV with the central memory CD45RO+CD62L+ cell phenotype expanded in PB and BM‐resident CTLCMV displayed distinct phenotypes when CMV was reactivated. Although the incidence of CMV reactivation was high in PMRD patients (87.67%), only 11.90% of them developed CMV disease. In conclusion, after PMRD using mixed grafts with ATG‐based conditioning, immune recovery to CMV seems to be early and fast, thereby reducing the incidence of CMV disease.
Skull Typology of Byzantine Dogs from the Theodosius Harbour at Yenikapı, Istanbul
Authors: Onar V. , Çakırlar C. , Janeczek M. , Kızıltan Z.
Published: February 2012

This study presents the results of craniometric analysis of 500 Byzantine Era dog skulls from the ancient site of the Theodosius Harbour in Istanbul (modern Yenikapı neighbourhood). To determine the typology of the skulls, up to 36 craniometric measurements were taken on each specimen. Fourteen indices and ratios were calculated from the measurements. Results show that the majority (97%) of the Byzantine dogs from the Yenikapı excavations were of mesocephalic type. Only 15 of the analysed skulls (3%) were of the dolichocephalic type. Only one dog skeleton has been recoveredin situduring the excavations; analysis indicates that this individual belonged to a mesocephalic type dog. Brachycephalic dog skulls were absent in the samples studied from Byzantine Yenikapı. The results give important insight in continuities and discontinuities in dog‐breeding traditions from the Roman to the Byzantine Eras, and between the West and the East during Medieval times.