bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural characteristics of yeast F1-ATPase before and after 16-degree rotation of the γ subunit: Theoretical analysis focused on the water-entropy effect
Authors: Yoshidome Takashi , Ito Yuko , Matubayasi Nobuyuki , Ikeguchi Mitunori , Kinoshita Masahiro
Published: July 2012

We have recently proposed a novel picture of the rotation mechanism for F1-ATPase [T. Yoshidome, Y. Ito, M. Ikeguchi, and M. Kinoshita, J. Am. Chem. Soc. 133, 4030 (2011)]10.1021/ja109594y. In the picture, the asymmetric packing in F1-ATPase, originating from the water-entropy effect, plays the key role in the rotation. Here, we analyze the differences between the experimentally determined structures of yeast F1-ATPase before and after 16° rotation of the γ subunit with the emphasis on the water-entropy effect. For each of these structures, we calculate the hydration entropies of three sub-complexes comprising the γ subunit, one of the β subunits, and two α subunits adjacent to them. The βE, βTP, and βDP subunits are involved in sub-complexes I, II, and III, respectively. The calculation is performed using a hybrid of the angle-dependent integral equation theory combined with the molecular model for water and the morphometric approach. The absolute value of the hydration entropy is in the following order: sub-complex I > sub-complex II > sub-complex III. The packing efficiency of the sub-complex follows the opposite order. The rotation gives rise to less efficient packing in sub-complex III and a corresponding water-entropy loss. However, the other two sub-complexes, accompanying water-entropy gains, become more efficiently packed. These results are consistent with our picture of the rotation mechanism, supporting its validity. The water-entropy analysis shows that the interfaces of αDP-βDP and αE-βE become more open after the rotation, which is in accord with the experimental observation.
Mass-analyzed threshold ionization of an excited state of lanthanum dioxide
Authors: Wu Lu , Liu Yang , Zhang Changhua , Li Shenggang , Dixon David A. , Yang Dong-Sheng
Published: July 2012

LaO2 was produced in a pulsed laser-vaporization molecular beam source and studied by mass-analyzed threshold ionization (MATI) spectroscopy and ab initio electronic structure calculations. The calculations included density functional theory, second-order perturbation theory, coupled cluster theory, and complete active space self-consistent field methods. The adiabatic ionization energy of the molecule and vibrational frequencies of the molecule and its cation were measured accurately for the first time from the MATI spectrum. Numerous ionization processes of lanthanum dioxide, peroxide, and superoxide were considered; the 3B2 ← 4B2 electronic transition of the dioxide was assigned upon comparison with the observed spectrum. The ionization energy and O-La-O bending frequency of the 4B2 neutral state are 4.9760 (6) eV and 92 cm−1, respectively. The La-O stretching and O-La-O bending frequencies of the 3B2 cationic state are 656 and 122 cm−1, respectively. The 4B2 state is formed by two electron transfer from lanthanum to oxygen atoms, and the 3B2 state is produced by the further removal of a lanthanum 6s-based electron.
Ultrafast semiconductor x-ray detector
Authors: Baker K. L. , Stewart R. E. , Steele P. T. , Vernon S. P. , Hsing W. W.
Published: July 2012

The National Ignition Campaign has the goal of developing a burning plasma platform producing up to ∼1019 neutrons in ∼20 picoseconds, ps. Diagnosis will require instruments operating with a time resolution of a few ps within this extremely large neutron flux environment. A diagnostic, which performs an ultrafast conversion of the x-ray signals into the optical regime, has been developed using a linearly chirped probe beam to measure the temporal history of the x-ray pulse. This diagnostic technique was tested on a laser-produced x-ray source and obtained a measurement of the full-width-at-half-maximum, FWHM, of the x-ray pulse of ∼7.2 ps.
Microwave absorption in nanocomposite material of magnetically functionalized carbon nanotubes
Authors: Labunov V. A. , Danilyuk A. L. , Prudnikava A. L. , Komissarov I. , Shulitski B. G. , Speisser C. , Antoni F. , Le Normand F. , Prischepa S. L.
Published: July 2012

The interaction of electromagnetic radiation in X and Ka bands with magnetic nanocomposite of disordered carbon nanotubes arrays has been investigated both experimentally and theoretically. Samples were synthesized on the quartz reactor walls by decomposition of ferrocene and xylene which provided random intercalation of iron phase nanoparticles in carbon nanotube array. The exhaustive characterization of the samples by means of the scanning electron microscopy, Raman spectroscopy, and x-ray photoemission spectroscopy was performed. It was found that the absorption of the electromagnetic wave monotonically increases with the frequency. To describe these experimental data, we extended the Bruggeman effective medium theory to a more complex case of a magnetic nanocomposite with randomly distributed spherical ferromagnetic nanoparticles in a conducting medium. The essential feature of the developed model is the consideration of the complex nature of the studied material. In particular, such important parameters as magnetic and dielectric properties of both the carbon nanotube medium and the nanoparticles, the volume concentration and the dimensions of the nanoparticles, the wave impedance of the resistive-capacitive shells of the conductive nanoparticles are explicitly taken into account in our model. Moreover, analysing the experimental results, we were able to obtain the frequency dependencies of permittivity and permeability of the studied nanocomposite.
Selective mode suppression in a W-band second harmonic coaxial-waveguide gyrotron backward-wave oscillator
Authors: Hung C. L. , Syu M. F. , Yang M. T. , Chen K. L.
Published: July 2012

A gyrotron backward-wave oscillator (gyro-BWO) encounters increasingly severe mode competition problems during development toward the goal of higher power at high frequencies. A coaxial interaction waveguide with distributed losses is proposed to enhance the stability and frequency tunability of a W-band second harmonic gyro-BWO. The losses of the inner and outer cylinders complement each other and effectively stabilize all of the competing modes while having minor effects on the operating mode. Under stable operating conditions, the W-band second harmonic coaxial gyro-BWO has a predicted peak output power of 71 kW with a magnetic tuning bandwidth of 1.0 GHz.
Very high thermoelectric power factor in a Fe3O4/SiO2/p-type Si(100) heterostructure
Authors: Viskadourakis Z. , Paramês M. L. , Conde O. , Zervos M. , Giapintzakis J.
Published: July 2012

The thermoelectric and transport properties of a Fe3O4/SiO2/p-Si(100) heterostructure have been investigated between 100 and 300 K. Both Hall and Seebeck coefficients change sign from negative to positive with increasing temperature while the resistivity drops sharply due to tunneling of carriers into the p-Si(100). The low resistivity and large Seebeck coefficient of Si give a very high thermoelectric power factor of 25.5 mW/K2m at 260 K which is an underestimated, lower limit value and is related to the density of states and difference in the work functions of Fe3O4 and Si(100) that create an accumulation of majority holes at the p-Si/SiO2 interface.
Serine/threonine acetylation of TGFβ-activated kinase (TAK1) by
Yersinia pestis
YopJ inhibits innate immune signaling
Authors: Paquette Nicholas , Conlon Joseph , Sweet Charles , Rus Florentina , Wilson Lindsay , Pereira Andrea , Rosadini Charles V. , Goutagny Nadege , Weber Alexander N. R. , Lane William S. , Shaffer Scott A. , Maniatis Stephanie , Fitzgerald Katherine A. , Stuart Lynda , Silverman Neal
Published: July 2012

The Gram-negative bacteria
Yersinia pestis
, causative agent of plague, is extremely virulent. One mechanism contributing to
Y. pestis
virulence is the presence of a type-three secretion system, which injects effector proteins, Yops, directly into immune cells of the infected host. One of these Yop proteins, YopJ, is proapoptotic and inhibits mammalian NF-κB and MAP-kinase signal transduction pathways. Although the molecular mechanism remained elusive for some time, recent work has shown that YopJ acts as a serine/threonine acetyl-transferase targeting MAP2 kinases. Using
Drosophila
as a model system, we find that YopJ inhibits one innate immune NF-κB signaling pathway (IMD) but not the other (Toll). In fact, we show YopJ mediated serine/threonine acetylation and inhibition of dTAK1, the critical MAP3 kinase in the IMD pathway. Acetylation of critical serine/threonine residues in the activation loop of
Drosophila
TAK1 blocks phosphorylation of the protein and subsequent kinase activation. In addition, studies in mammalian cells show similar modification and inhibition of hTAK1. These data present evidence that TAK1 is a target for YopJ-mediated inhibition.
Structural basis for receptor sharing and activation by interleukin-20 receptor-2 (IL-20R2) binding cytokines
Authors: Logsdon Naomi J. , Deshpande Ashlesha , Harris Bethany D. , Rajashankar Kanagalaghatta R. , Walter Mark R.
Published: July 2012

Interleukin 20 (IL-20) is a pleotropic IL-10 family cytokine that protects epithelial surfaces from pathogens. However, dysregulated IL-20 signaling is implicated in several human pathologies including psoriasis, rheumatoid arthritis, atherosclerosis, and osteoporosis. IL-20, and related cytokines IL-19 and IL-24, designated IL-20 subfamily cytokines (IL-20SFCs), induce cellular responses through an IL-20R1/IL-20R2 (type I) receptor heterodimer, whereas IL-20 and IL-24 also signal through the IL-22R1/IL-20R2 (type II) receptor complex. The crystal structure of the IL-20/IL-20R1/IL-20R2 complex reveals how type I and II complexes discriminate cognate from noncognate ligands. The structure also defines how the receptor–cytokine interfaces are affinity tuned to allow distinct signaling through a receptor complex shared by three different ligands. Our results provide unique insights into the complexity of IL-20SFC signaling that may be critical in the design of mechanistic-based inhibitors of IL-20SFC–mediated inflammatory disease.
Mn(II) oxidation by an ascomycete fungus is linked to superoxide production during asexual reproduction
Authors: Hansel Colleen M. , Zeiner Carolyn A. , Santelli Cara M. , Webb Samuel M.
Published: July 2012

Manganese (Mn) oxides are among the most reactive minerals within the environment, where they control the bioavailability of carbon, nutrients, and numerous metals. Although the ability of microorganisms to oxidize Mn(II) to Mn(III/IV) oxides is scattered throughout the bacterial and fungal domains of life, the mechanism and physiological basis for Mn(II) oxidation remains an enigma. Here, we use a combination of compound-specific chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete filamentous fungus,
Stilbella aciculosa
, oxidizes Mn(II) to Mn oxides by producing extracellular superoxide during cell differentiation. The reactive Mn oxide phase birnessite and the reactive oxygen species superoxide and hydrogen peroxide are colocalized at the base of asexual reproductive structures. Mn oxide formation is not observed in the presence of superoxide scavengers (e.g., Cu) and inhibitors of NADPH oxidases (e.g., diphenylene iodonium chloride), enzymes responsible for superoxide production and cell differentiation in fungi. Considering the recent identification of Mn(II) oxidation by NADH oxidase-based superoxide production by a common marine bacterium (
Roseobacter
sp.), these results introduce a surprising homology between some prokaryotic and eukaryotic organisms in the mechanisms responsible for Mn(II) oxidation, where oxidation appears to be a side reaction of extracellular superoxide production. Given the versatility of superoxide as a redox reactant and the widespread ability of fungi to produce superoxide, this microbial extracellular superoxide production may play a central role in the cycling and bioavailability of metals (e.g., Hg, Fe, Mn) and carbon in natural systems.
Fighting malaria with engineered symbiotic bacteria from vector mosquitoes
Authors: Wang Sibao , Ghosh Anil K. , Bongio Nicholas , Stebbings Kevin A. , Lampe David J. , Jacobs-Lorena Marcelo
Published: July 2012

The most vulnerable stages of
Plasmodium
development occur in the lumen of the mosquito midgut, a compartment shared with symbiotic bacteria. Here, we describe a strategy that uses symbiotic bacteria to deliver antimalaria effector molecules to the midgut lumen, thus rendering host mosquitoes refractory to malaria infection. The
Escherichia coli
hemolysin A secretion system was used to promote the secretion of a variety of anti-
Plasmodium
effector proteins by
Pantoea agglomerans
, a common mosquito symbiotic bacterium. These engineered
P. agglomerans
strains inhibited development of the human malaria parasite
Plasmodium falciparum
and rodent malaria parasite
Plasmodium berghei
by up to 98%. Significantly, the proportion of mosquitoes carrying parasites (prevalence) decreased by up to 84% for two of the effector molecules, scorpine, a potent antiplasmodial peptide and (EPIP)
4
, four copies of
Plasmodium
enolase–plasminogen interaction peptide that prevents plasminogen binding to the ookinete surface. We demonstrate the use of an engineered symbiotic bacterium to interfere with the development of
P. falciparum
in the mosquito. These findings provide the foundation for the use of genetically modified symbiotic bacteria as a powerful tool to combat malaria.
Hot days induced by precipitation deficits at the global scale
Authors: Mueller Brigitte , Seneviratne Sonia I.
Published: July 2012

Global warming increases the occurrence probability of hot extremes, and improving the predictability of such events is thus becoming of critical importance. Hot extremes have been shown to be induced by surface moisture deficits in some regions. In this study, we assess whether such a relationship holds at the global scale. We find that wide areas of the world display a strong relationship between the number of hot days in the regions’ hottest month and preceding precipitation deficits. The occurrence probability of an above-average number of hot days is over 70% after precipitation deficits in most parts of South America as well as the Iberian Peninsula and Eastern Australia, and over 60% in most of North America and Eastern Europe, while it is below 30–40% after wet conditions in these regions. Using quantile regression analyses, we show that the impact of precipitation deficits on the number of hot days is asymmetric, i.e. extreme high numbers of hot days are most strongly influenced. This relationship also applies to the 2011 extreme event in Texas. These findings suggest that effects of soil moisture-temperature coupling are geographically more widespread than commonly assumed.
Gain and loss of multiple functionally related, horizontally transferred genes in the reduced genomes of two microsporidian parasites
Authors: Pombert Jean-François , Selman Mohammed , Burki Fabien , Bardell Floyd T. , Farinelli Laurent , Solter Leellen F. , Whitman Douglas W. , Weiss Louis M. , Corradi Nicolas , Keeling Patrick J.
Published: July 2012

Microsporidia of the genus
Encephalitozoon
are widespread pathogens of animals that harbor the smallest known nuclear genomes. Complete sequences from
Encephalitozoon intestinalis
(2.3 Mbp) and
Encephalitozoon cuniculi
(2.9 Mbp) revealed massive gene losses and reduction of intergenic regions as factors leading to their drastically reduced genome size. However, microsporidian genomes also have gained genes through horizontal gene transfers (HGT), a process that could allow the parasites to exploit their hosts more fully. Here, we describe the complete sequences of two intermediate-sized genomes (2.5 Mbp), from
Encephalitozoon hellem
and
Encephalitozoon romaleae
. Overall, the
E
.
hellem
and
E
.
romaleae
genomes are strikingly similar to those of
Encephalitozoon cuniculi
and
Encephalitozoon intestinalis
in both form and content. However, in addition to the expected expansions and contractions of known gene families in subtelomeric regions, both species also were found to harbor a number of protein-coding genes that are not found in any other microsporidian. All these genes are functionally related to the metabolism of folate and purines but appear to have originated by several independent HGT events from different eukaryotic and prokaryotic donors. Surprisingly, the genes are all intact in
E
.
hellem
, but in
E
.
romaleae
those involved in de novo synthesis of folate are all pseudogenes. Overall, these data suggest that a recent common ancestor of
E
.
hellem
and
E
.
romaleae
assembled a complete metabolic pathway from multiple independent HGT events and that one descendent already is dispensing with much of this new functionality, highlighting the transient nature of transferred genes.
Large mutational target size for rapid emergence of bacterial persistence
Authors: Girgis Hany S. , Harris Kendra , Tavazoie Saeed
Published: July 2012

Phenotypic heterogeneity displayed by a clonal bacterial population permits a small fraction of cells to survive prolonged exposure to antibiotics. Although first described over 60 y ago, the molecular mechanisms underlying this behavior, termed persistence, remain largely unknown. To systematically explore the genetic basis of persistence, we selected a library of transposon-mutagenized
Escherichia coli
cells for survival to multiple rounds of lethal ampicillin exposure. Application of microarray-based genetic footprinting revealed a large number of loci that drastically elevate persistence frequency through null mutations and domain disruptions. In one case, the C-terminal disruption of methionyl-tRNA synthetase (MetG) results in a 10,000-fold higher persistence frequency than wild type. We discovered a mechanism by which null mutations in transketolase A (
tktA
) and glycerol-3-phosphate (G3P) dehydrogenase (
glpD
) increase persistence through metabolic flux alterations that increase intracellular levels of the growth-inhibitory metabolite methylglyoxal. Systematic double-mutant analyses revealed the genetic network context in which such persistent mutants function. Our findings reveal a large mutational target size for increasing persistence frequency, which has fundamental implications for the emergence of antibiotic tolerance in the clinical setting.
Giant birefringence in optical antenna arrays with widely tailorable optical anisotropy
Authors: Kats Mikhail A. , Genevet Patrice , Aoust Guillaume , Yu Nanfang , Blanchard Romain , Aieta Francesco , Gaburro Zeno , Capasso Federico
Published: July 2012

The manipulation of light by conventional optical components such as lenses, prisms, and waveplates involves engineering of the wavefront as it propagates through an optically thick medium. A unique class of flat optical components with high functionality can be designed by introducing abrupt phase shifts into the optical path, utilizing the resonant response of arrays of scatterers with deeply subwavelength thickness. As an application of this concept, we report a theoretical and experimental study of birefringent arrays of two-dimensional (V- and Y-shaped) optical antennas which support two orthogonal charge-oscillation modes and serve as broadband, anisotropic optical elements that can be used to locally tailor the amplitude, phase, and polarization of light. The degree of optical anisotropy can be designed by controlling the interference between the waves scattered by the antenna modes; in particular, we observe a striking effect in which the anisotropy disappears as a result of destructive interference. These properties are captured by a simple, physical model in which the antenna modes are treated as independent, orthogonally oriented harmonic oscillators.
Are there multiple memory systems? Tests of models of implicit and explicit memory
Authors: Shanks David R. , Berry Christopher J.
Published: July 2012

[Formula: see text]

This article reviews recent work aimed at developing a new framework, based on signal detection theory, for understanding the relationship between explicit (e.g., recognition) and implicit (e.g., priming) memory. Within this framework, different assumptions about sources of memorial evidence can be framed. Application to experimental results provides robust evidence for a single-system model in preference to multiple-systems models. This evidence comes from several sources including studies of the effects of amnesia and ageing on explicit and implicit memory. The framework allows a range of concepts in current memory research, such as familiarity, recollection, fluency, and source memory, to be linked to implicit memory. More generally, this work emphasizes the value of modern computational modelling techniques in the study of learning and memory.
The bigram trough hypothesis and the syllable number effect in lexical decision
Authors: Muncer Steven J. , Knight David C.
Published: July 2012

There has been an increasing volume of evidence supporting the role of the syllable in various word processing tasks. It has, however, been suggested that syllable effects may be caused by orthographic redundancy. In particular, it has been proposed that the presence of bigram troughs at syllable boundaries cause what are seen as syllable effects. We investigated the bigram trough hypothesis as an explanation of the number of syllables effect for lexical decision in five-letter words and nonwords from the British Lexicon Project. The number of syllables made a significant contribution to prediction of lexical decision times along with word frequency and orthographic similarity. The presence of a bigram trough did not. For nonwords, the number of syllables made a significant contribution to prediction of lexical decision times only for nonwords with relatively long decision times. The presence of a bigram trough made no contribution. The evidence presented suggests that the bigram trough cannot be an explanation of the syllable number effect in lexical decision. A comparison of the results from words and nonwords is interpreted as providing some support for dual-route models of reading.
A Standardized Terminology for Describing Reproductive Development in Fishes
Authors: Brown-Peterson Nancy J. , Wyanski David M. , Saborido-Rey Fran , Macewicz Beverly J. , Lowerre-Barbieri Susan K.
Published: July 2012

As the number of fish reproduction studies has proliferated, so has the number of gonadal classification schemes and terms. This has made it difficult for both scientists and resource managers to communicate and for comparisons to be made among studies. We propose the adoption of a simple, universal terminology for the phases in the reproductive cycle, which can be applied to all male and female elasmobranch and teleost fishes. These phases were chosen because they define key milestones in the reproductive cycle; the phases include immature, developing, spawning capable, regressing, and regenerating. Although the temporal sequence of events during gamete development in each phase may vary among species, each phase has specific histological and physiological markers and is conceptually universal. The immature phase can occur only once. The developing phase signals entry into the gonadotropin-dependent stage of oogenesis and spermatogenesis and ultimately results in gonadal growth. The spawning capable phase includes (1) those fish with gamete development that is sufficiently advanced to allow for spawning within the current reproductive cycle and (2) batch-spawning females that show signs of previous spawns (i.e., postovulatory follicle complex) and that are also capable of additional spawns during the current cycle. Within the spawning capable phase, an actively spawning subphase is defined that corresponds to hydration and ovulation in females and spermiation in males. The regressing phase indicates completion of the reproductive cycle and, for many fish, completion of the spawning season. Fish in the regenerating phase are sexually mature but reproductively inactive. Species-specific histological criteria or classes can be incorporated within each of the universal phases, allowing for more specific divisions (subphases) while preserving the overall reproductive terminology for comparative purposes. This terminology can easily be modified for fishes with alternate reproductive strategies, such as hermaphrodites (addition of a transition phase) and livebearers (addition of a gestation phase).
The Use of Hepatic and Somatic Indices and Histological Information to Characterize the Reproductive Dynamics of Atlantic Sardine Sardina pilchardus from the Portuguese Coast
Authors: Nunes Cristina , Silva Alexandra , Soares Eduardo , Ganias Konstantinos
Published: July 2012

Samples of Atlantic sardine Sardina pilchardus (also known as European pilchard) were collected bimonthly from 2004 to 2008 off the central west coast of Portugal to describe the reproductive activity of this indeterminate batch-spawning species; compare the seasonality of somatic growth, condition, and feeding; and evaluate differences between sexes. Monthly assessments of individual biological information for both males and females were complemented by histological analysis of ovaries during 1 year and liver tissues (both sexes) at different times of the reproductive cycle. The temporal patterns of the gonadosomatic index and various histological indices (most advanced oocyte stage, atresia incidence and prevalence, and spawning activity) indicated that Atlantic sardine were reproductively active mainly from October to March and that residual activity occurred in the remaining months. For both sexes, condition indices (hepatosomatic index, relative weight, and amount of fat stored) increased mainly during spring, reached a maximum at the end of summer just before the subsequent spawning season began, and then decreased during autumn and winter, declining to minimum levels at the beginning of spring coincident with a significant reduction in reproductive activity. Somatic growth took place mainly during spring and early summer for both sexes. The observed seasonal patterns in these biological properties suggest a seasonal transition from a period in which energy resources are allocated to reproduction (autumn and winter) to a period in which resources are allocated to growth and fat deposition (spring and summer). The only exception was the distinct hepatosomatic index pattern and the histological differences in hepatocytes between males and females during the spawning season, which may be related to the dual function of the liver in females (lipid metabolism and yolk precursor synthesis).
Skipped Spawning in Fishes: More Common than You Might Think
Authors: Rideout Rick M. , Tomkiewicz Jonna
Published: July 2012

The traditional view of iteroparity in fishes is one of an annual reproductive cycle that culminates each year in spawning. More recently, a more flexible view of fish reproduction has been adopted, including the potential for mature fish to skip spawning. Here, we review the abundance of recent research on skipped spawning, covering a broad range of fishes with diverse life history strategies. Evidence for skipped spawning has been collected by use of traditional histological techniques as well as modern technological advances, such as satellite tags and the ability to track fish movements based on elemental and isotope signatures. Skipped spawning is most commonly attributed to deficient diet and poor nutritional condition. Advances made in this field of study in recent years include descriptions of hormonal changes that precede and perhaps initiate skipped spawning, the development of life history models that incorporate the potential for skipped spawning, and estimates of the degree to which skipped spawning influences the reproductive potential of fish populations. In addition to summarizing this new research, we attempt to advance current knowledge by (1) providing the first review discussion of skipped spawning in males, (2) exploring skipped spawning in anadromous fishes by using the Atlantic salmon Salmo salar as an example, and (3) discussing the potential for and difficulties in identifying skipped spawning in species with indeterminate fecundity.
Variations in Growth of Tautog in Nursery Areas in Narragansett Bay and Rhode Island Coastal Ponds
Authors: Mateo Ivan , Durbin Edward G. , Bengtson David A. , Durant Daisy
Published: July 2012

In the present study, the growth of juvenile tautogs Tautoga onitis in Narragansett Bay (Gaspee Point, Mount Hope Bay, and Rose Island) and Rhode Island coastal ponds (Point Judith and Charleston ponds) was evaluated by means of otolith microstructure. The widths of the daily increments in otoliths in the region that represents the postsettlement period (20–50 d) of tautogs collected in two separate years were compared among these stations. Significant differences were found in the growth trajectories within stations between years as well as among stations in each year. This study demonstrates that there can be significant variability in short-term growth for juvenile tautogs within and among estuaries. This variability may change from year to year, potentially affecting the interpretation of growth. A better understanding of the conditions affecting single factors of tautog production, such as growth over several years, may enable researchers to successfully characterize fish nursery value.
Relationship between Gulf Menhaden Recruitment and Mississippi River Flow: Model Development and Potential Application for Management
Authors: Vaughan Douglas S. , Govoni John J. , Shertzer Kyle W.
Published: July 2012

The Gulf menhaden Brevoortia patronus is one of the most abundant pelagic fishes in the northern coastal Gulf of Mexico (hereafter, “Gulf”) and is the principal forage for various commercial and sport fishes, sea birds, and marine mammals. Part of the life history of Gulf menhaden is spent on the continental shelf and part is spent within estuaries. Adults spawn near the mouth of the Mississippi River, and larvae aggregate within the river plume front. Larval Gulf menhaden transit the continental shelf and enter estuaries of the northern Gulf as juveniles. Govoni (1997) demonstrated an association between the discharge of the Mississippi and Atchafalaya rivers and Gulf menhaden recruitment. In particular, he found an inverse association between Mississippi River discharge and estimated recruitment of half-year-old fish based on recruitment data from Vaughan et al. (1996). Vaughan et al. (2000) updated this relationship with a regression analysis. Here, we revisit the relationship with additional years of data through 2004. The inverse relationship continues to hold. In addition, we reframed this relationship to produce a 1-year-ahead prediction model for forecasting recruitment to age 1 from Mississippi River discharge; this model can be used in proactive fishery management. Finally, we revisited the stock assessment model of Vaughan et al. (2007) and demonstrated an improvement in model performance when information on annual river discharge was incorporated.

Received August 4, 2010; accepted March 10, 2011
Class II formin targeting to the cell cortex by binding PI(3,5)P2 is essential for polarized growth
Authors: van Gisbergen Peter A.C. , Li Ming , Wu Shu-Zon , Bezanilla Magdalena
Published: July 2012

Class II formins are key regulators of actin and are essential for polarized plant cell growth. Here, we show that the class II formin N-terminal phosphatase and tensin (PTEN) domain binds phosphoinositide-3,5-bisphosphate (PI(3,5)P2). Replacing the PTEN domain with polypeptides of known lipid-binding specificity, we show that PI(3,5)P2 binding was required for formin-mediated polarized growth. Via PTEN, formin also localized to the cell apex, phragmoplast, and to the cell cortex as dynamic cortical spots. We show that the cortical localization driven by binding to PI(3,5)P2 was required for function. Silencing the kinases that produce PI(3,5)P2 reduced cortical targeting of formin and inhibited polarized growth. We show a subset of cortical formin spots moved in actin-dependent linear trajectories. We observed that the linearly moving subpopulation of cortical formin generated new actin filaments de novo and along preexisting filaments, providing evidence for formin-mediated actin bundling in vivo. Taken together, our data directly link PI(3,5)P2 to generation and remodeling of the cortical actin array.
CENP-E–dependent BubR1 autophosphorylation enhances chromosome alignment and the mitotic checkpoint
Authors: Guo Yige , Kim Christine , Ahmad Sana , Zhang Jiayin , Mao Yinghui
Published: July 2012

How the state of spindle microtubule capture at the kinetochore is translated into mitotic checkpoint signaling remains largely unknown. In this paper, we demonstrate that the kinetochore-associated mitotic kinase BubR1 phosphorylates itself in human cells and that this autophosphorylation is dependent on its binding partner, the kinetochore motor CENP-E. This CENP-E–dependent BubR1 autophosphorylation at unattached kinetochores is important for a full-strength mitotic checkpoint to prevent single chromosome loss. Replacing endogenous BubR1 with a nonphosphorylatable BubR1 mutant, as well as depletion of CENP-E, the BubR1 kinase activator, results in metaphase chromosome misalignment and a decrease of Aurora B–mediated Ndc80 phosphorylation at kinetochores. Furthermore, expressing a phosphomimetic BubR1 mutant substantially reduces the incidence of polar chromosomes in CENP-E–depleted cells. Thus, the state of CENP-E–dependent BubR1 autophosphorylation in response to spindle microtubule capture by CENP-E is important for kinetochore function in achieving accurate chromosome segregation.
Structural and magnetic properties of tetragonal and orthorhombic Pr0.5Sr0.5MnO3 thin films
Authors: Chen X G , Ma X B , Yang Y B , Liu S Q , Du H L , Han J Z , Wang C S , Yang Y C , Yang J B
Published: July 2012

Pr0.5Sr0.5MO3 (PSMO) films with tetragonal and orthorhombic structures were epitaxially grown on a [0 0 1]-oriented LaAlO3 substrate (LAO) and a BaTiO3 substrate (BTO), respectively. It was found that the M(T) curves of the tetragonal PSMO films exhibit one/two distinguished magnetic transition peaks depending on the thickness of the film, which is related to the competition between ferromagnetic (FM) and antiferromagnetic (AFM) interactions in the films. The tetragonal film shows an insulator-to-metal transition (MIT) as well as a metal-to-semiconductor transition with increasing temperature from 10 to 300 K, and the AFM insulating state of the film can be transformed into the metallic state under a magnetic field of 5 T due to the collapse of the AFM insulator state. For the orthorhombic film on BTO substrate, only a FM metallic state is observed without MIT from 10 to 300 K. In addition, a significant colossal magnetoresistance effect is observed with a wide temperature range from T
C (182 K) to 10 K for the tetragonal films, while only around T
C (240 K) for the orthorhombic films.
Neonatal DNA methylation profile in human twins is specified by a complex interplay between intrauterine environmental and genetic factors, subject to tissue-specific influence
Authors: Gordon Lavinia , Joo Jihoon E. , Powell Joseph E. , Ollikainen Miina , Novakovic Boris , Li Xin , Andronikos Roberta , Cruickshank Mark N. , Conneely Karen N. , Smith Alicia K. , Alisch Reid S. , Morley Ruth , Visscher Peter M. , Craig Jeffrey M. , Saffery Richard
Published: July 2012

Comparison between groups of monozygotic (MZ) and dizygotic (DZ) twins enables an estimation of the relative contribution of genetic and shared and nonshared environmental factors to phenotypic variability. Using DNA methylation profiling of ∼20,000 CpG sites as a phenotype, we have examined discordance levels in three neonatal tissues from 22 MZ and 12 DZ twin pairs. MZ twins exhibit a wide range of within-pair differences at birth, but show discordance levels generally lower than DZ pairs. Within-pair methylation discordance was lowest in CpG islands in all twins and increased as a function of distance from islands. Variance component decomposition analysis of DNA methylation in MZ and DZ pairs revealed a low mean heritability across all tissues, although a wide range of heritabilities was detected for specific genomic CpG sites. The largest component of variation was attributed to the combined effects of nonshared intrauterine environment and stochastic factors. Regression analysis of methylation on birth weight revealed a general association between methylation of genes involved in metabolism and biosynthesis, providing further support for epigenetic change in the previously described link between low birth weight and increasing risk for cardiovascular, metabolic, and other complex diseases. Finally, comparison of our data with that of several older twins revealed little evidence for genome-wide epigenetic drift with increasing age. This is the first study to analyze DNA methylation on a genome scale in twins at birth, further highlighting the importance of the intrauterine environment on shaping the neonatal epigenome.
Pressure-induced phase transitions in L-alanine, revisited. Corrigendum
Authors: Tumanov N. A. , Boldyreva E. V. , Kolesov B. A. , Kurnosov A. V. , Quesada Cabrera R.
Published: July 2012

Tables 2 and 3 in the paper by Tumanov et al. [(2010), Acta Cryst. B66, 458–471] are corrected.
Inductive Selectivity in Children’s Cross‐Classified Concepts
Authors: Nguyen Simone P.
Published: July 2012

Cross‐classified items pose an interesting challenge to children’s induction as these items belong to many different categories, each of which may serve as a basis for a different type of inference. Inductive selectivity is the ability to appropriately make different types of inferences about a single cross‐classifiable item based on its different category memberships. This research includes 5 experiments that examine the development of inductive selectivity in 3‐, 4‐, and 5‐year‐olds (n = 272). Overall, the results show that by age 4, children have inductive selectivity with taxonomic and script categories. That is, children use taxonomic categories to make biochemical inferences about an item whereas script categories to make situational inferences about an item.
Effects of high and low stress on proinflammatory and antiinflammatory cytokines
Authors: Koh Kyung Bong , Lee Young‐Joon , Beyn Keyng Min , Chu Sang Hee , Kim Duck Man , Seo Won Youl
Published: July 2012

The effects of stress, which varies throughout an academic year, on proinflammatory and antiinflammatory cytokines were examined in 44 medical students. This was tested by comparing stimulated cytokines during a baseline period, stress period, and poststress vacation period. During the stress period, compared with the baseline period, levels of IL‐6 were reduced, while levels of IL‐10 were elevated. During the poststress vacation period, compared with the stress period, levels of IL‐6 and TNF‐α were increased. However, the changes in stress‐related psychological and physiological variables were not significantly associated with changes in levels of proinflammatory and antiinflammatory cytokines. These results suggest that vacation is more likely to have a counterstress effect on proinflammatory cytokines than on an antiinflammatory cytokine and that a stressor may affect changes in immune function independently of self‐reported stress.
Risk Attitudes and Political Participation
Authors: Kam Cindy D.
Published: July 2012

This article contributes to existing explanations of political participation by proposing that citizens’ attitudes towards risk predict participation. I argue that people who are risk accepting participate in political life because politics offers novelty and excitement. Analyses of two independent Internet surveys establish a positive, significant relationship between risk attitudes and general political participation. The analyses also suggest that the relationship between risk attitudes and action varies with the political act: people who are more risk accepting are more likely to participate in general political acts, but they are no more or less likely to turn out in elections. Further analyses suggest that two key mechanisms—novelty seeking and excitement seeking—underlie the relationship between risk attitudes and political participation.
Relationship Between Workplace Spirituality and Organizational Citizenship Behavior Among Nurses Through Mediation of Affective Organizational Commitment
Authors: Kazemipour Farahnaz , Mohamad Amin Salmiah , Pourseidi Bahram
Published: July 2012

Purpose: This study aims to investigate the relationships between workplace spirituality, organizational citizenship behavior (OCB), and affective organizational commitment among nurses, and whether affective commitment mediates the relationship between workplace spirituality and OCB.

Methods: In the present correlational study, a cross‐sectional design was employed, and data were collected using a questionnaire‐based survey. Based on the random sampling, 305 nurses were chosen and questionnaires were distributed among respondents in four public and general hospitals located in Kerman, Iran. To analyze the data descriptive statistics, Pearson coefficient, simple and multiple regression, and path analyses were also conducted.

Findings: Workplace spirituality has a positive influence on nurses’ OCB and affective commitment. Workplace spirituality explained 16% of the variation in OCB, while it explained 35% of the variation in affective commitment among nurses. Moreover, affective organizational commitment mediated the impact of workplace spirituality on OCB.

Conclusions: Workplace spirituality predicts nurses’ OCB and affective organizational commitment. It emphasizes benefits from the new perspective of workplace spirituality, particularly among nurses who need to be motivated in their work.

Clinical Relevance: This study illustrates that there are potential benefits owing to the positive influence of workplace spirituality on OCB and affective commitment among nurses. Managers of nursing services should consider workplace spirituality and its positive influence on nurses’ outcomes in order to improve their performance and, subsequently, the healthcare system.
Increased Heat Shock Protein 70 Gene Expression in the Brains of Cocaine‐Related Fatalities may be Reflective of Postdrug Survival and Intervention rather than Excited Delirium
Authors: Johnson Magen M. , David James A. , Michelhaugh Sharon K. , Schmidt Carl J. , Bannon Michael J.
Published: July 2012

Abstract:  Cocaine‐related fatalities can pose forensic challenges, particularly when accompanied by excited delirium (ED) syndrome and interventions by law enforcement and medical personnel. A recent report concluded that elevated heat shock protein 70 (HSP70) expression in autopsy brain samples constitutes a reliable forensic biomarker for the identification of ED as a cause of death. The present study quantified the abundance of both HSPA1A and HSPA1B gene (HSP70‐encoding) transcripts in midbrain specimens from a series of cocaine‐related fatalities and matched drug‐free control subjects. HSP70 expression was increased significantly in cocaine abusers as a group compared to control subjects, irrespective of the presence or absence of ED. Furthermore, elevated HSP70 expression was predictive of a period of survival between cocaine use and death that included medical and/or police intervention. The present data do not support the assertion that HSP70 expression is a reliable brain biomarker for identifying ED as a cause of death.
Diagnosis of Hemorrhagic Stroke in an Exhumed Brain After Three Years of Burial in a Deep Grave
Authors: Omalu Bennet , Hammers Jennifer , Luckasevic Todd
Published: July 2012

Abstract:  We present the forensic neuropathologic analysis of an exhumed decomposed brain following long‐term interment in a 50‐year‐old white woman, who had been buried for 34 months. Next of kin authorized exhumation of the body for an autopsy to determine the cause of death. The embalmed body was anatomically intact and revealed decompositional changes with mold colonies. Internal viscera showed intact histomorphology. The brain revealed diffuse congestive swelling and extracellular edema with dissecting parenchymal hemorrhage and hematoma originating from the left putamen and thalamus and extending to the left lateral ventricle. Excitotoxic neuronal injury as well as penumbric parenchymal changes was noted. Cause of death was determined to be a hypertensive cerebral parenchymal hemorrhage. This case and our previously reported case are sentinel cases, which should encourage and guide the forensic neuropathologic work‐up and investigation of causes of death in spite of long‐term burial in deep graves.
Comparison of the Volatile Organic Compounds from Different Biological Specimens for Profiling Potential*
Authors: Kusano Maiko , Mendez Eladio , Furton Kenneth G.
Published: July 2012

Previous work has demonstrated the ability to differentiate individuals based on the analysis of human scent hand odor chemicals. In this paper, a range of forensic biological specimens are shown to also have the ability to differentiate individuals based upon the volatile organic compounds (VOCs) present. Human VOC profiles from hand odor, oral fluid, breath, blood, and urine of 31 individuals were analyzed by solid‐phase microextraction–gas chromatography–mass spectrometry (SPME‐GC‐MS) and combined methods of chromatogram comparison, Spearman rank correlation comparison, and principal component analysis. Intra‐specimen comparisons demonstrated the distinguishability of individuals above 99%. Inter‐specimen VOC profiles from the same individual were found to be too different to be used for scent‐matching purposes, with Spearman rank coefficients below 0.15. A 6‐month VOC profile monitoring of two individuals demonstrated the consistency of VOC profiles over time across specimens.
Voice gender differences and separation of simultaneous talkers in cochlear implant users with residual hearing
Authors: Visram Anisa S. , Kluk Karolina , McKay Colette M.
Published: July 2012

Perception of a target voice in the presence of a competing talker, of same or different gender as the target, was investigated in cochlear implant users, in implant-alone and bimodal (acoustic hearing in the non-implanted ear) conditions. Recordings of two male and two female talkers acted as targets and maskers, to investigate whether bimodal benefit increased for different compared to same gender target/maskers due to increased ability to perceive and utilize fundamental frequency and spectral-shape differences. In both listening conditions participants showed benefit of target/masker gender difference. There was an overall bimodal benefit, which was independent of target/masker gender difference.