bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial and temporal effects of grazing management and rainfall on the vertebrate fauna of a tropical savanna
Authors: Kutt A. S. , Vanderduys E. P. , O'Reagain P.
Published: June 2012

Grazing by domestic livestock is one of the most widespread uses of the rangelands of Australia. There is limited information on the effects of grazing by domestic livestock on the vertebrate fauna of Australia and the establishment of a long-term grazing experiment in north-eastern Queensland at Wambiana provided an opportunity to attempt an examination of the changes in vertebrate fauna as a consequence of the manipulation of stocking rates. The aim was to identify what the relative effects of vegetation type, stocking rate and other landscape-scale environmental factors were on the patterns recorded. Sixteen 1-ha sites were established within three replicated treatments (moderate, heavy and variable stocking rates). The sites were sampled in the wet and dry seasons in 1999–2000 (T0) and again in 2003–04 (T1). All paddocks of the treatments were burnt in 1999. Average annual rainfall declined markedly between the two sampling periods, which made interpretation of the data difficult. A total of 127 species of vertebrate fauna comprising five amphibian, 83 bird, 27 reptile and 12 mammal species were recorded. There was strong separation in faunal composition from T0 to T1 although changes in mean compositional dissimilarity between the grazing stocking rate treatments were less well defined. There was a relative change in abundance of 24 bird, four mammal and five reptile species from T0 to T1. The generalised linear modelling identified that, in the T1 data, there was significant variation in the abundance of 16 species explained by the grazing and vegetation factors. This study demonstrated that vertebrate fauna assemblage did change and that these changes were attributable to the interplay between the stocking rates, the vegetation types on the sites surveyed, the burning of the experimental paddocks and the decrease in rainfall over the course of the two surveys. It is recommended that the experiment is sampled again but that the focus should be on a rapid survey of abundant taxa (i.e. birds and reptiles) to allow an increase in the frequency of sampling and replication of the data. This would help to articulate more clearly the trajectory of vertebrate change due to the relative effects of stocking rates compared with wider landscape environmental changes. Given the increasing focus on pastoral development in northern Australia, any opportunity to incorporate the collection of data on biodiversity into grazing manipulation experiments should be taken for the assessment of the effects of land management on faunal species.
Characterising the spatial and temporal activities of free-ranging cows from GPS data
Authors: Anderson Dean M. , Winters Craig , Estell Rick E. , Fredrickson Ed L. , Doniec Marek , Detweiler Carrick , Rus Daniela , James Darren , Nolen Barbara
Published: June 2012

Electronic tracking provides a unique way to document behaviour by cows on a continuous basis. Over 2 years 17 beef cows with calves were fitted with global positioning system (GPS) devices programmed to record uncorrected GPS locations at 1-s intervals in a semi-desert rangeland. Each cow was periodically observed during daylight hours and foraging, walking and stationary (standing/lying) activity times were recorded across days and individual cows to calculate a mean travel rate for each activity. Data without observers present were collected immediately preceding and following the abrupt weaning of calves at between 223 and 234 days of age to evaluate the potential of classifying various travel rates into foraging, walking and stationary activity. The three activities were further characterised within a 24-h period based on the sun’s angle with respect to the horizon. Only data from cows whose equipment acquired ≥ 90% of the potential GPS positional data among consecutive days were analysed. Due to problems with the equipment, data from two cows in 2009 and two cows in 2011 met these criteria. The interval evaluated consisted of four 24-h periods before abrupt weaning and seven 24-h periods following weaning. Results suggested that uncorrected 1-s positional GPS data are satisfactory to classify the behaviour by free-ranging beef cows into foraging, walking and stationary activities. Furthermore, abrupt weaning caused cows to change their spatial and temporal behaviour across and within days. Overall, travel by cows increased post-weaning with subtle within-day behavioural changes. Further research will be required to fully understand the biological importance of spatio-temporal behaviour to optimise cattle and landscape management goals.
The diet of the dingo (Canis lupus dingo and hybrids) in north-eastern Australia: a supplement to the paper of Brook and Kutt (2011)
Authors: Allen Lee , Goullet Mark , Palmer Russell
Published: June 2012

Dingoes and other wild dogs (Canis lupus dingo and hybrids) are generalist predators that consume a wide variety of different prey species within their range. Little is known, however, of the diets of dingoes in north-eastern Australia where the potential for impacts by dingoes exists. Recently new information has been provided on the diets of dingoes from several sites in Queensland, Australia, significantly adding to the body of published knowledge on ecosystems within this region. Further information on the diet of dingoes in north-eastern Australia is added from 1460 scats collected from five sites, representing tropical savannahs, tropical offshore islands (and a matched mainland area), dry sclerophyll forests and peri-urban areas on the fringe of Townsville. Macropods, possums and bandicoots were found to be common prey for dingoes in these areas. Evidence suggested that the frequency of prey remains in scats can be an unreliable indicator of predation risk to potential prey and it was found that novel and unexpected prey species appear in dingo diets as preferred prey become unavailable. The results support the generalisation that dingoes prefer medium- to large-sized native prey species when available but also highlight the capacity for dingoes to exploit populations of both large and small prey species that might not initially be considered at risk from predation based solely on data on scats.
Foraging behaviour of beef cattle in the hilly terrain of a Mediterranean grassland
Authors: Henkin Z. , Ungar E. D. , Dolev A.
Published: June 2012

The objective of this study was to determine the role of terrain in the foraging behaviour of beef cows grazing hilly Mediterranean grasslands. The study was conducted in eastern Galilee, Israel, during 2002 and 2003 on two similar 28-ha paddocks encompassing distinct terrain types in terms of slope and rock cover. The paddocks were continuously grazed by cows from mid winter (January–February) to autumn (September) at two different stocking rates (1.1 and 0.56 cows per ha). From early June to the end of September the cows were offered poultry litter ad libitum as a supplementary feed. The location and activity of cows were monitored with GPS collars during four periods in each year: early spring (February–March), late spring (April), early summer (June) and late summer (August). Herbage mass was measured at the beginning of each of these periods. During early and late spring, when the herbage mass and nutritive value of herbage were high, the cows spent 40–50% of the day grazing, with peaks in the morning and afternoon. In the dry, late summer period (August), grazing of the herbage was 20–22% of the day, occurring only in the early morning and late afternoon with sporadic bouts of grazing until midnight. In all periods the cows tended to prefer the flattest terrain sites. As the herbage mass declined to 1000–1500 kg ha–1, the exploitation of the pasture during grazing became increasingly similar among the different terrains. Even on relatively small paddocks, where grazing pressure was close to the full potential of the site, free-ranging cows tended to prefer less sloping and rocky sites. It is concluded that the grazing strategy of beef cows is determined by the interaction between terrain, the distribution of the herbage mass and the nutritive value of the herbage. As herbage mass declines during the growing season, the distribution of grazing becomes uniform and all terrain types are exploited.
Primary somatosensory cortex discriminates affective significance in social touch
Authors: Gazzola Valeria , Spezio Michael L. , Etzel Joset A. , Castelli Fulvia , Adolphs Ralph , Keysers Christian
Published: June 2012

Another person’s caress is one of the most powerful of all emotional social signals. How much the primary somatosensory cortices (SIs) participate in processing the pleasantness of such social touch remains unclear. Although ample empirical evidence supports the role of the insula in affective processing of touch, here we argue that SI might be more involved in affective processing than previously thought by showing that the response in SI to a sensual caress is modified by the perceived sex of the caresser. In a functional MRI study, we manipulated the perceived affective quality of a caress independently of the sensory properties at the skin: heterosexual males believed they were sensually caressed by either a man or woman, although the caress was in fact invariantly delivered by a female blind to condition type. Independent analyses showed that SI encoded, and was modulated by, the visual sex of the caress, and that this effect is unlikely to originate from the insula. This suggests that current models may underestimate the role played by SI in the affective processing of social touch.
Structure and regulon of
Campylobacter jejuni
ferric uptake regulator Fur define apo-Fur regulation
Authors: Butcher James , Sarvan Sabina , Brunzelle Joseph S. , Couture Jean-François , Stintzi Alain
Published: June 2012

The full regulatory potential of the ferric uptake regulator (Fur) family of proteins remains undefined despite over 20 years of study. We report herein an integrated approach that combines both genome-wide technologies and structural studies to define the role of Fur in
Campylobacter jejuni
(Cj). CjFur ChIP-chip assays identified 95 genomic loci bound by CjFur associated with functions as diverse as iron acquisition, flagellar biogenesis, and non-iron ion transport. Comparative analysis with transcriptomic data revealed that CjFur regulation extends beyond solely repression and also includes both gene activation and iron-independent regulation. Computational analysis revealed the presence of an elongated holo-Fur repression motif along with a divergent holo-Fur activation motif. This diversity of CjFur DNA-binding elements is supported by the crystal structure of CjFur, which revealed a unique conformation of its DNA-binding domain and the absence of metal in the regulatory site. Strikingly, our results indicate that the apo-CjFur structure retains the canonical V-shaped dimer reminiscent of previously characterized holo-Fur proteins enabling DNA interaction. This conformation stems from a structurally unique hinge domain that is poised to further contribute to CjFur’s regulatory functions by modulating the orientation of the DNA-binding domain upon binding of iron. The unique features of the CjFur crystal structure rationalize the binding sequence diversity that was uncovered during ChIP-chip analysis and defines apo-Fur regulation.
Specific inactivation of two immunomodulatory
SIGLEC
genes during human evolution
Authors: Wang Xiaoxia , Mitra Nivedita , Secundino Ismael , Banda Kalyan , Cruz Pedro , Padler-Karavani Vered , Verhagen Andrea , Reid Chris , Lari Martina , Rizzi Ermanno , Balsamo Carlotta , Corti Giorgio , De Bellis Gianluca , Longo Laura ,   NISC Comparative Sequencing Program, Beggs William , Caramelli David , Tishkoff Sarah A. , Hayakawa Toshiyuki , Green Eric D. , Mullikin James C. , Nizet Victor , Bui Jack , Varki Ajit ,   NISC Comparative Sequencing Program Members, Benjamin Betty , Blakesley Robert , Bouffard Gerry , Brooks Shelise , Chu Grace , Coleman Holly , Dekhtyar Mila , Gregory Michael , Guan Xiaobin , Gupta Jyoti , Han Joel , Hargrove April , Ho Shi-ling , Johnson Taccara , Legaspi Richelle , Lovett Sean , Maduro Quino , Masiello Cathy , Maskeri Baishali , McDowell Jenny , Montemayor Casandra , Novotny Betsy , Park Morgan , Riebow Nancy , Schandler Karen , Schmidt Brian , Sison Christina , Stantripop Mal , Thomas James , Vemulapalli Meg , Young Alice
Published: June 2012

Sialic acid-recognizing Ig-like lectins (Siglecs) are signaling receptors that modulate immune responses, and are targeted for interactions by certain pathogens. We describe two primate Siglecs that were rendered nonfunctional by single genetic events during hominin evolution after our common ancestor with the chimpanzee.
SIGLEC13
was deleted by an
Alu
-mediated recombination event, and a single base pair deletion disrupted the ORF of
SIGLEC17
. Siglec-13 is expressed on chimpanzee monocytes, innate immune cells that react to bacteria. The human
SIGLEC17P
pseudogene mRNA is still expressed at high levels in human natural killer cells, which bridge innate and adaptive immune responses. As both resulting pseudogenes are homozygous in all human populations, we resurrected the originally encoded proteins and examined their functions. Chimpanzee Siglec-13 and the resurrected human Siglec-17 recruit a signaling adapter and bind sialic acids. Expression of either Siglec in innate immune cells alters inflammatory cytokine secretion in response to Toll-like receptor-4 stimulation. Both Siglecs can also be engaged by two potentially lethal sialylated bacterial pathogens of newborns and infants, agents with a potential impact on reproductive fitness. Neanderthal and Denisovan genomes show human-like sequences at both loci, corroborating estimates that the initial pseudogenization events occurred in the common ancestral population of these hominins. Both loci also show limited polymorphic diversity, suggesting selection forces predating the origin of modern humans. Taken together, these data suggest that genetic elimination of Siglec-13 and/or Siglec-17 represents signatures of infectious and/or other inflammatory selective processes contributing to population restrictions during hominin origins.
Impaired function of the Tie-2 receptor contributes to vascular leakage and lethality in anthrax
Authors: Ghosh Chandra C. , Mukherjee Aditi , David Sascha , Knaus Ulla G. , Stearns-Kurosawa Deborah J. , Kurosawa Shinichiro , Parikh Samir M.
Published: June 2012

The anthrax lethal toxin (LT) enters host cells and enzymatically cleaves MAPKKs or MEKs. How these molecular events lead to death from anthrax remains poorly understood, but published reports suggest a direct effect of LT on vascular permeability. We have found that LT challenge in mice disrupts signaling through Tie-2, a tonically activated receptor tyrosine kinase in the endothelium. Genetic manipulations favoring Tie-2 activation enhanced interendothelial junctional contacts, prevented vascular leakage, and promoted survival following a lethal dose of LT. Cleavage of MEK1/2 was necessary for LT to induce endothelial barrier dysfunction, and activated Tie-2 signaled through the uncleaved fraction of MEKs to prevent LT’s effects on the endothelium. Finally, primates infected with toxin-secreting
Bacillus anthracis
bacilli developed a rapid and marked imbalance in the endogenous ligands that signal Tie-2, similar to that seen in LT-challenged mice. Our results show that
B. anthracis
LT blunts signaling through Tie-2, thereby weakening the vascular barrier and contributing to lethality of the disease. Measurement of circulating Tie-2 ligands and manipulation of Tie-2 activity may represent future prognostic and therapeutic avenues for humans exposed to
B. anthracis
.
Wet-surface–enhanced ellipsometric contrast microscopy identifies slime as a major adhesion factor during bacterial surface motility
Authors: Ducret Adrien , Valignat Marie-Pierre , Mouhamar Fabrice , Mignot Tâm , Theodoly Olivier
Published: June 2012

In biology, the extracellular matrix (ECM) promotes both cell adhesion and specific recognition, which is essential for central developmental processes in both eukaryotes and prokaryotes. However, live studies of the dynamic interactions between cells and the ECM, for example during motility, have been greatly impaired by imaging limitations: mostly the ability to observe the ECM at high resolution in absence of specific staining by live microscopy. To solve this problem, we developed a unique technique, wet-surface enhanced ellipsometry contrast (Wet-SEEC), which magnifies the contrast of transparent organic materials deposited on a substrate (called Wet-surf) with exquisite sensitivity. We show that Wet-SEEC allows both the observation of unprocessed nanofilms as low as 0.2 nm thick and their accurate 3D topographic reconstructions, directly by standard light microscopy. We next used Wet-SEEC to image slime secretion, a poorly defined property of many prokaryotic and eukaryotic organisms that move across solid surfaces in absence of obvious extracellular appendages (gliding). Using combined Wet-SEEC and fluorescent-staining experiments, we observed slime deposition by gliding
Myxococcus xanthus
cells at unprecedented resolution. Altogether, the results revealed that in this bacterium, slime associates preferentially with the outermost components of the motility machinery and promotes its adhesion to the substrate on the ventral side of the cell. Strikingly, analogous roles have been proposed for the extracellular proteoglycans of gliding diatoms and apicomplexa, suggesting that slime deposition is a general means for gliding organisms to adhere and move over surfaces.
Bioinspired nanofibers support chondrogenesis for articular cartilage repair
Authors: Coburn Jeannine M. , Gibson Matthew , Monagle Sean , Patterson Zachary , Elisseeff Jennifer H.
Published: June 2012

Articular cartilage repair remains a significant and growing clinical challenge with the aging population. The native extracellular matrix (ECM) of articular cartilage is a 3D structure composed of proteinaceous fibers and a hydrogel ground substance that together provide the physical and biological cues to instruct cell behavior. Here we present fibrous scaffolds composed of poly(vinyl alcohol) and the biological cue chondroitin sulfate with fiber dimensions on the nanoscale for application to articular cartilage repair. The unique, low-density nature of the described nanofiber scaffolds allows for immediate cell infiltration for optimal tissue repair. The capacity for the scaffolds to facilitate cartilage-like tissue formation was evaluated in vitro. Compared with pellet cultures, the nanofiber scaffolds enhance chondrogenic differentiation of mesenchymal stems cells as indicated by increased ECM production and cartilage specific gene expression while also permitting cell proliferation. When implanted into rat osteochondral defects, acellular nanofiber scaffolds supported enhanced chondrogenesis marked by proteoglycan production minimally apparent in defects left empty. Furthermore, inclusion of chondroitin sulfate into the fibers enhanced cartilage-specific type II collagen synthesis in vitro and in vivo. By mimicking physical and biological cues of native ECM, the nanofiber scaffolds enhanced cartilaginous tissue formation, suggesting their potential utility for articular cartilage repair.
Multisite phosphoregulation of Cdc25 activity refines the mitotic entrance and exit switches
Authors: Lu Lucy X. , Domingo-Sananes Maria Rosa , Huzarska Malwina , Novak Bela , Gould Kathleen L.
Published: June 2012

Cyclin-dependent kinase 1 (Cdk1) kinase dephosphorylation and activation by Cdc25 phosphatase are essential for mitotic entry. Activated Cdk1 phosphorylates Cdc25 and other substrates, further activating Cdc25 to form a positive feedback loop that drives the abrupt G2/mitosis switch. Conversely, mitotic exit requires Cdk1 inactivation and reversal of Cdk1 substrate phosphorylation. This dephosphorylation is mediated, in part, by Clp1/Cdc14, a Cdk1-antagonizing phosphatase, which reverses Cdk1 phosphorylation of itself, Cdc25, and other Cdk1 substrates. Thus, Cdc25 phosphoregulation is essential for proper G2–M transition, and its contributions to cell cycle control have been modeled based on studies using
Xenopus
and human cell extracts. Because cell extract systems only approximate in vivo conditions where proteins interact within dynamic cellular environments, here, we use
Schizosaccharomyces pombe
to characterize, both experimentally and mathematically, the in vivo contributions of Cdk1-mediated phosphorylation of Cdc25 to the mitotic transition. Through comprehensive mapping of Cdk1 phosphosites on Cdc25 and characterization of phosphomutants, we show that Cdc25 hyperphosphorylation by Cdk1 governs Cdc25 catalytic activation, the precision of mitotic entry, and unvarying cell length but not Cdc25 localization or abundance. We propose a mathematical model that explains Cdc25 regulation by Cdk1 through a distributive and disordered phosphorylation mechanism that ultrasensitively activates Cdc25. We also show that Clp1/Cdc14 dephosphorylation of Cdk1 sites on Cdc25 controls the proper timing of cell division, a mechanism that is likely due to the double negative feedback loop between Clp1/Cdc14 and Cdc25 that controls the abruptness of the mitotic exit switch.
Effect of mass transfer on the oxygen reduction reaction catalyzed by platinum dendrimer encapsulated nanoparticles
Authors: Dumitrescu Ioana , Crooks Richard M.
Published: June 2012

Here we report on the effect of the mass transfer rate (
k
t
) on the oxygen reduction reaction (ORR) catalyzed by Pt dendrimer-encapsulated nanoparticles (DENs) comprised of 147 and 55 atoms (Pt
147
and Pt
55
). The experiments were carried out using a dual-electrode microelectrochemical device, which enables the study of the ORR under high
k
t
conditions with simultaneous detection of H
2
O
2
. At low
k
t
(0.02 to 0.12 cm s
-1
) the effective number of electrons involved in ORR,
n
eff
, is 3.7 for Pt
147
and 3.4 for Pt
55
. As
k
t
is increased, the mass-transfer-limited current for the ORR becomes significantly lower than the value predicted by the Levich equation for a 4-electron process regardless of catalyst size. However, the percentage of H
2
O
2
detected remains constant, such that
n
eff
barely changes over the entire
k
t
range explored (0.02 cm s
-1
). This suggests that mass transfer does not affect
n
eff
, which has implications for the mechanism of the ORR on Pt nanoparticles. Interestingly, there is a significant difference in
n
eff
for the two sizes of Pt DENs (
n
eff
 = 3.7 and 3.5 for Pt
147
and Pt
55
, respectively) that cannot be assigned to mass transfer effects and that we therefore attribute to a particle size effect.
Tobacco calmodulin-like protein provides secondary defense by binding to and directing degradation of virus RNA silencing suppressors
Authors: Nakahara Kenji S. , Masuta Chikara , Yamada Syouta , Shimura Hanako , Kashihara Yukiko , Wada Tomoko S. , Meguro Ayano , Goto Kazunori , Tadamura Kazuki , Sueda Kae , Sekiguchi Toru , Shao Jun , Itchoda Noriko , Matsumura Takeshi , Igarashi Manabu , Ito Kimihito , Carthew Richard W. , Uyeda Ichiro
Published: June 2012

RNA silencing (RNAi) induced by virus-derived double-stranded RNA (dsRNA), which is in a sense regarded as a pathogen-associated molecular pattern (PAMP) of viruses, is a general plant defense mechanism. To counteract this defense, plant viruses express RNA silencing suppressors (RSSs), many of which bind to dsRNA and attenuate RNAi. We showed that the tobacco calmodulin-like protein, rgs-CaM, counterattacked viral RSSs by binding to their dsRNA-binding domains and sequestering them from inhibiting RNAi. Autophagy-like protein degradation seemed to operate to degrade RSSs with the sacrifice of rgs-CaM. These RSSs could thus be regarded as secondary viral PAMPs. This study uncovered a unique defense system in which an rgs-CaM–mediated countermeasure against viral RSSs enhanced host antiviral RNAi in tobacco.
Accurate protein structure modeling using sparse NMR data and homologous structure information
Authors: Thompson James M. , Sgourakis Nikolaos G. , Liu Gaohua , Rossi Paolo , Tang Yuefeng , Mills Jeffrey L. , Szyperski Thomas , Montelione Gaetano T. , Baker David
Published: June 2012

While information from homologous structures plays a central role in X-ray structure determination by molecular replacement, such information is rarely used in NMR structure determination because it can be incorrect, both locally and globally, when evolutionary relationships are inferred incorrectly or there has been considerable evolutionary structural divergence. Here we describe a method that allows robust modeling of protein structures of up to 225 residues by combining

,
13
C, and
15
N backbone and
13
C
β
chemical shift data, distance restraints derived from homologous structures, and a physically realistic all-atom energy function. Accurate models are distinguished from inaccurate models generated using incorrect sequence alignments by requiring that (
i
) the all-atom energies of models generated using the restraints are lower than models generated in unrestrained calculations and (
ii
) the low-energy structures converge to within 2.0 Å backbone rmsd over 75% of the protein. Benchmark calculations on known structures and blind targets show that the method can accurately model protein structures, even with very remote homology information, to a backbone rmsd of 1.2–1.9 Å relative to the conventional determined NMR ensembles and of 0.9–1.6 Å relative to X-ray structures for well-defined regions of the protein structures. This approach facilitates the accurate modeling of protein structures using backbone chemical shift data without need for side-chain resonance assignments and extensive analysis of NOESY cross-peak assignments.
Photochemically driven redox chemistry induces protocell membrane pearling and division
Authors: Zhu Ting F. , Adamala Katarzyna , Zhang Na , Szostak Jack W.
Published: June 2012

Prior to the evolution of complex biochemical machinery, the growth and division of simple primitive cells (protocells) must have been driven by environmental factors. We have previously demonstrated two pathways for fatty acid vesicle growth in which initially spherical vesicles grow into long filamentous vesicles; division is then mediated by fluid shear forces. Here we describe a different pathway for division that is independent of external mechanical forces. We show that the illumination of filamentous fatty acid vesicles containing either a fluorescent dye in the encapsulated aqueous phase, or hydroxypyrene in the membrane, rapidly induces pearling and subsequent division in the presence of thiols. The mechanism of this photochemically driven pathway most likely involves the generation of reactive oxygen species, which oxidize thiols to disulfide-containing compounds that associate with fatty acid membranes, inducing a change in surface tension and causing pearling and subsequent division. This vesicle division pathway provides an alternative route for the emergence of early self-replicating cell-like structures, particularly in thiol-rich surface environments where UV-absorbing polycyclic aromatic hydrocarbons (PAHs) could have facilitated protocell division. The subsequent evolution of cellular metabolic processes controlling the thiol:disulfide redox state would have enabled autonomous cellular control of the timing of cell division, a major step in the origin of cellular life.
Anomalously weak solar convection
Authors: Hanasoge Shravan M. , Duvall Thomas L. , Sreenivasan Katepalli R.
Published: June 2012

Convection in the solar interior is thought to comprise structures on a spectrum of scales. This conclusion emerges from phenomenological studies and numerical simulations, though neither covers the proper range of dynamical parameters of solar convection. Here, we analyze observations of the wavefield in the solar photosphere using techniques of time-distance helioseismology to image flows in the solar interior. We downsample and synthesize 900 billion wavefield observations to produce 3 billion cross-correlations, which we average and fit, measuring 5 million wave travel times. Using these travel times, we deduce the underlying flow systems and study their statistics to bound convective velocity magnitudes in the solar interior, as a function of depth and spherical-harmonic degree
ℓ
. Within the wavenumber band
ℓ
 < 60, convective velocities are 20–100 times weaker than current theoretical estimates. This constraint suggests the prevalence of a different paradigm of turbulence from that predicted by existing models, prompting the question: what mechanism transports the heat flux of a solar luminosity outwards? Advection is dominated by Coriolis forces for wavenumbers
ℓ
 < 60, with Rossby numbers smaller than approximately 10
-2
at
r
/
R
⊙
 = 0.96, suggesting that the Sun may be a much faster rotator than previously thought, and that large-scale convection may be quasi-geostrophic. The fact that isorotation contours in the Sun are not coaligned with the axis of rotation suggests the presence of a latitudinal entropy gradient.
Metalloenzyme-like catalyzed isomerizations of sugars by Lewis acid zeolites
Authors: Bermejo-Deval Ricardo , Assary Rajeev S. , Nikolla Eranda , Moliner Manuel , Román-Leshkov Yuriy , Hwang Son-Jong , Palsdottir Arna , Silverman Dorothy , Lobo Raul F. , Curtiss Larry A. , Davis Mark E.
Published: June 2012

Isomerization of sugars is used in a variety of industrially relevant processes and in glycolysis. Here, we show that hydrophobic zeolite beta with framework tin or titanium Lewis acid centers isomerizes sugars, e.g., glucose, via reaction pathways that are analogous to those of metalloenzymes. Specifically, experimental and theoretical investigations reveal that glucose partitions into the zeolite in the pyranose form, ring opens to the acyclic form in the presence of the Lewis acid center, isomerizes into the acyclic form of fructose, and finally ring closes to yield the furanose product. The zeolite catalysts provide processing advantages over metalloenzymes such as an ability to work at higher temperatures and in acidic conditions that allow for the isomerization reaction to be coupled with other important conversions.
Temporal expression of microRNA cluster miR-17-92 regulates effector and memory CD8
+
T-cell differentiation
Authors: Wu Tuoqi , Wieland Andreas , Araki Koichi , Davis Carl W. , Ye Lilin , Hale J. Scott , Ahmed Rafi
Published: June 2012

MicroRNAs are important regulators of various developmental and physiological processes. However, their roles in the CD8
+
T-cell response are not well understood. Using an acute viral infection model, we show that microRNAs of the miR-17-92 cluster are strongly induced after T-cell activation, down-regulated after clonal expansion, and further silenced during memory development. miR-17-92 promotes cell-cycle progression of effector CD8
+
T cells, and its expression is critical to the rapid expansion of these cells. However, excessive miR-17-92 expression enhances mammalian target of rapamycin (mTOR) signaling and strongly skews the differentiation toward short-lived terminal effector cells. Failure to down-regulate miR-17-92 leads to a gradual loss of memory cells and defective central memory cell development. Therefore, our results reveal a temporal expression pattern of miR-17-92 by antigen-specific CD8
+
T cells during viral infection, the precise control of which is critical to the effector expansion and memory differentiation of CD8
+
T cells.
Wenn die Möglichkeit in Notwendigkeit umschlägt
Authors: Gerogiorgakis Stamatios D.
Published: June 2012

Aristotle produced several arguments to vindicate the futura contingentia and to refute the conception of modalities which do not allow incidental facts. This conception was coined mainly by Diodorus Cronus and implied the view that whatever may happen, is to happen necessarily. Although Aristotle condemned this view and refuted the theology which it implies, Diodorean modalities were employed by the scholastics (at least since Abaelard, as Leibniz pointed out) to support their theology. Abaelard’s Diodorean formula reads: God wishes (and ultimately cannot but do) no more and no less than what He is able to do – i. e. God’s ability to do something implies necessity. In the Summa theologiae, Thomas Aquinas employed Diodorean modalities along with this result of Abaelard’s. Leibniz himself confessed his debt to Diodorean modalities as well as to the work of Abaelard in formulating his own ontological proof. Kurt Gödel was under the influence of Leibniz when he wrote his »Ontological Proof«, which employs Diodorean modalities. — For the Greek-speaking scholars of the Middle Ages, however, Aristotelian influences were stronger than Diodorean as regards theory building on modalities. Philosophers from the East from the 2nd to the 11th century A.D., such as Alexander of Aphrodisias, John Philoponus and Michael Psellos, condemned Diodorean modalities as fallacious. In the same period, Greek Church Fathers such as Cyril of Alexandria, Maximus Confessor and John of Damascus gave an orthodox account of God and the modalities, according to which (contrary to what Abaelard says) God is able to do whatever He wishes. The absence of Leibniz-like modal ontological proofs in the Greek tradition seems more plausible under these circumstances.
Sätze und Dinge
Authors: Rode Christian
Published: June 2012

This article examines the role of the mediaeval theory of the propositio in re, as proposed by Walter Burley and others, which bears a striking resemblance to the theory of the “proposition” advocated by G. E. Moore and B. Russell. Burley’s proposition composed of real things has the function of an ultimate significate for every sentence of natural language. The main problems of such a theory are on the one hand absurdities like a bird flying between the subject and predicate of a sentence, on the other hand Burley’s assumption that a relation of identity holds between subject and predicate, which might render propositiones in re tautological. Moreover, the particular nature of this relation is left unexplained. But these difficulties can be solved: The former by applying objective being, being as being cognized, to the terms of a propositio, as did Scotus and Franciscus de Prato, the latter by specifying multiple forms of real predication as being or being-in-something apart from a mere identity-relation (e. g. William Milverley).
Zum Begriff der formalen und materialen Folgerung
Authors: Weber-Schroth Stephanie
Published: June 2012

The theory of consequences was one of the most important developments in logic during the Middle Ages. The distinction between formal consequences (consequentiae formales) and material consequences (consequentiae materiales) was probably introduced by Ockham and soon became the main division of consequences, to be found in nearly all 14th-century treatises on the theory of consequences. This paper discusses the concept of a formal and material consequence according to the English tradition (which differs from the continental tradition). It is based mainly on Richard Bil­lingham’s De consequentiis, but also takes into account other 14th-century authors. Billingham defines the formal consequence as one where the consequent is understood in (intelligitur in) the antecedent and differentiates this kind of consequence from the material one. The definition is followed by a list of rules for valid consequences. However, with respect to some of these valid consequences the question arises whether they are formal or not and, if they are formal, how it is possible to explain the criterion of the intelligitur in. After explaining the material (part 2.1) and the formal consequence (part 2.2) and discussing these difficulties, the question is raised whether the intelligitur in is an appropriate structural criterion to distinguish between formal and material consequences (part 2.3). Finally, two interpretations for the intelligitur in compatible with the text situation are proposed.
Aristoteles und der naturalistische Fehlschluß
Authors: Müller Jörn
Published: June 2012

Is Aristotle’s ethics founded on a naturalistic fallacy? This article examines in detail the criticism which was levelled at Aristotle by George Edward Moore in his Principia Ethica in 1903. In order to check the correctness of this assumption, Aristotle’s notion of goodness is reconstructed by an analysis of his theoretical as well as his ethical writings. The picture which emerges shows that Aristotle does not understand goodness as a univocal term but as an analogical concept the focal meaning of which is closely related to the perfection of the different natural things or species. Since Moore’s criticism presupposes a univocal definition of goodness, Aristotle’s treatment of this notion does not fall prey to it. Although his understanding of goodness is connected with his teleology of nature, Aristotle is not guilty of deriving ›ought‹ from ›is‹; therefore, his ethics is also immune to the second argument against the naturalistic fallacy which is usually traced back to David Hume.
Differenzen zwischen Augustin und Eckhart in der Beurteilung des epikureischen Lustbegriffs
Authors: Hoffmann Heinz
Published: June 2012

Eckhart describes lust as a principle of life in his German Sermon 63. The examples he mentions indicate that he was inspired by his reading of Augustine’s De civitate dei. But while Augustine condemns the Epicurean concept of pleasure emphatically, Eckhart – by contrast – admits that pleasure has an eminent positive value because it is the goal of creation.
Modern Scholarship (1900-2000) on Albertus Magnus: A Complement
Authors: Tremblay Bruno
Published: June 2012

The renewal of interest in Albert Magnus’ works which has taken place in the last one hundred years or so has in fact produced a multilingual body of studies whose size and diversity are making it more and more difficult for the scholar to identify and to know precisely and with certainty what has been written about this very important philosopher. The partial bibliographies which have been published throughout the 20th century were of some use, but none can compare, in terms of completeness, to the new, selectively annotated bibliography composed by I. M. Resnick and K. F. Kitchell. After briefly analyzing this impressive piece of scholarship and identifying some of the mistakes it inevitably contains, the present paper provides a list of approximately 350 items which are missing from Resnick and Kitchell’s bibliography and which for the most part were written before 2001.
Document design: Complex evolution
Authors: Hunter Lawrie
Published: June 2012

Karen A. Schriver is the author of dynamics in document design: creating texts for readers, an extensive, multidimensional portrait of what readers need from documents and of ways to integrate word and image in order to better meet those needs. She is the former codirector of the graduate program in technical communication and document design at Carnegie Mellon University (Pittsburgh, Pennsylvania). She has been a visiting professor at the University of Utrecht in the Netherlands and at the University of Washington in Seattle. A popular speaker, she has presented her ideas in Japan, the United Kingdom, Canada, and across the United States. Winner of five awards for her research, she now heads her own company, KSA Document Design & Research. She helps organizations improve the quality of their paper and electronic communications through strategies based on research and best practices. She is now working on a book about the nature of expertise in information design. When she is not writing, working with clients, or running to catch a plane, she spends time playing with her two crazy dogs: Cody (a Bearded Collie) and Tika (a little Muttley). She can be contacted via e-mail at schriver@cmu.edu
Text types and varying degrees of interpretative constraint
Authors: Wang Sungsune
Published: June 2012

This paper attempts to identify linguistic regularity underlying text-internal type variation by analyzing three different text types in relevance-theoretic, pragmatic perspective, and suggests a unitary text-classification criterion. It is assumed that text type variation is a matter of how tightly or loosely the text producer constrains the text interpretation by controlling the verbal givenness of information. This assumption is tested through the analysis of text interpretation processes focusing on what types of utterances and referring expressions are used in each different text type (academic text, news text, poetic text) following the relevance-theoretic account of utterance type variation. The result of the analysis shows that a certain degree of interpretative constraint at the utterance level is kept constant throughout a text and that text types vary according to the degrees of interpretative constraint. Such a finding provides a theoretical basis for explaining how text types form a continuum for practical relevance.
Current views on risk communication and their implications for crisis and reputation management
Authors: Gutteling Jan M.
Published: June 2012

Organizations prepare for crisis communication by designing, implementing, and evaluating procedures, scenarios, and emergency measures. In addition to crisis communication, risk communication is a concern for many organizations as well. Risk communication is viewed as an interactive, multi-actor democratic process. Traditionally, risk communication is seen as a linear, top-down, elitist, expert-to-public approach. In this paper, the relation between crisis communication and risk communication is described. In addition, a model is presented based on the notion that crisis communication should be proactive, and focusing on the management of the relation between the organization and its relevant stakeholders or the organization’s reputation. The new thinking on the risk communication process is essential for an organization’s crisis and reputation management.
Technology in crisis management systems - Ideas and effects
Authors: Johansson Bjorn , Artman Henrik , Waern Yvonne
Published: June 2012

This article presents empirically based research on the use of future technology for crisis management. In particular, it sets out to challenge ideas of future technology by contrasting them with examples from current practice with new, high-tech systems in emergency rescue centers and military command and control environments. The following three dichotomies are singled out: to start with, that between commitment and information storage;secondly, that between silence and transparency; and finally, that between mimetic representation and interpretation of representa- tions. Our research points to a contradiction between current system design for crisis management systems and actual work practice. Generally speaking, it is suggested that the information technology is becoming both a burden and a saver.
The influence of politeness on the perception of product recall notices
Authors: Van Waes Luuk , van Wijk Carel
Published: June 2012

When companies decide — or are forced — to publish a product recall notice, their aim is to give consumers clear information on how to handle the problem and to warn them of a possible danger. On the other hand companies try to preserve their corporate image in order to guarantee a (commercial) relation in the future. This article deals with the question whether politeness strategies lead to differences in the appreciation, acceptance and perception of product recall notices. In two experimental studies we evaluated the effect of positive and negative politeness strategies in different conditions. The results show that the use of elaborated negative politeness strategies positively influences the appreciation and acceptance of the message, and has a positive effect on the perception of the corporate image. However in a context where the product recall warns of a severe risk, writers of product recalls should use politeness strategies more cautiously. In this context the use of politeness strategies even seems to have a negative effect on the acceptability of the recall message.
The effect of prenotification techniques on refusal rate in telephone surveys
Authors: Gerritsen Marinel , Palmen Marie-José
Published: June 2012

Response rate is of great importance for the representativeness of a study. When it is low, there is a chance that response is selective, as the people who refuse may constitute a selective sample of the target population. Much research has already been done into the sociopsychological aspects affecting response, but so far little attention has been paid to the effect of different communicative approaches. In our study we examine the effects of a two-phased communication plan on refusal rate in telephone surveys. In real-life experiments, we investigated the effects of two prenotification techniques: sending advance letters and leaving a message on an answeringmachine or voice mail. Sending advance letters led to a statistically significant decrease in refusals by 25%, but leaving a message on answering machines or voice mail led to no statistically significant decrease in refusals. The results are interpreted in the light of Compliance Theory and Elaboration Likelihood Theory. Possible consequences for research bureaus that conduct telephone surveys are discussed.
The phylogenesis of hypotaxis in Vedic
Authors: Viti Carlotta
Published: June 2012

Hypotaxis has been found since the earliest records of Vedic, especially for relative and adverbial functions. However, some adverbial relations more often resort to alternative structures such as clause juxtaposition, nominalization, or particles. The principles underlying the inconsistent representation of hypotaxis remain unclear. My analysis of clause linkage strategies in the Rig-Veda shows that non-hypotactic constructions are used preferentially for relations, such as purpose or concession, that are considered complex in studies of the ontogenesis of hypotaxis in first language acquisition. This suggests that the spread of hypotaxis follows a cognitive path of increasing complexity through the diachronic stages of Vedic. Moreover, the different entrenchment of some adverbial relations, particularly of conditionals, in Vedic with respect to ontogenetic studies allows us to refine the concept of cognitive complexity in the adverbial domain, and to consider it as a contrast to the speaker’s expectations rather than to the extra-linguistic world, as it is usually seen.
The use of colloquial words in advanced French interlanguage
Authors: Dewaele Jean-Marc , Regan Vera
Published: June 2012

This article addresses the issue of underrepresentation or avoidance of colloquial words in a cross-sectional corpus of advanced French interlanguage (IL) of 29 Dutch L1 speakers and in a longitudinal corpus of 6 Hiberno-Irish English L1 speakers compared with a control group of 6 native speakers of French. The main independent variable analysed in the longitudinal corpus is the effect of spending a year in a francophone environment. This analysis is supplemented by a separate study of sociobiographical and psychological factors that affect the use of colloquial vocabulary in the cross-sectional corpus. Colloquial words are not exceptionally complex morphologically and present no specific grammatical difficulties, yet they are very rare in our data. Multivariate regression analyses suggest that only active authentic communication in the target language (TL) predicts the use of colloquial lexemes in the cross-sectional corpus. This result was confirmed in the longitudinal corpus where a t-test showed that the proportion of colloquial lexemes increased significantly after a year abroad.