bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermoporometry applied to hydrothermally aged silica hydrogels
Authors: Titulaer M. K. , van Miltenburg J. C. , Jansen J. B. H. , Geus J. W.
Published: September 2010

Aged porous 13 wt% silica hydrogel beads were characterized by measuring the freezing point depression of water in silica gel pores, which provides information about the ice crystal radius (Rn), the ice‐pore volume (Vn), the pore shape (F), and the ice‐surface area (An). Hydrothermal treatment at high temperatures increases both the pore size and apparent pore volume of not previously dried hydrogel beads. The ice crystal radius, is increased from 8.6 to 27 nm after ageing for 7 h at 473K, while the apparent ice‐pore volume increases from 0.9 to 1.4 ml/g. The pore size and pore volume decrease upon drying. At Rn values of 8.6 and 27 nm, the drop ΔRn on drying is 5.1 and 7 nm, respectively, and the decrease of Vn, ΔVn, is 0.4 and 0.6 ml/g, which amounts to 44 and 38%, respectively. The exceptionally small decrease of pore volume for a gel upon drying suggests that this measurement is underestimated by thermoporometry. The soft gel is compressed as liquid is drained from the network during freezing. The apparent increase of the pore volume of the hydrogel must be interpreted to indicate the effect of stiffening (through ageing) on the amount of compression during the measurement. Based on the probably real pore volume Vn of the hydrogel of 1.4 ml/g, instead of 0.9 ml/g, the pore volume decrease at Rn = 8.6 nm would be 0.9, not 0.4 ml/g, so the percentage change would be 64%, rather than 44%. By contrast, at a Rn value of 10.9 and 25 nm, the thermoporometric surface area An* of the hydrogels, which is the surface area of the ice crystals corrected for a non‐freezing layer of water, is equal to the BET surface areas of the xerogel measured by nitrogen sorption, which indicates that no pores are enclosed. The increase in pore volume of the aged xerogels by both mercury penetration and thermoporometry is real. It reflects the coarsening and stiffening by ageing, which leads to less shrinkage during drying. The xerogels are probably stiff enough that they experience little contraction on application of thermoporometry.
The initial oxidation of polycrystalline thorium
Authors: Bagge‐Hansen M. , Outlaw R. A. , Zhu M. Y. , Manos D. M.
Published: September 2010

The initial oxidation of clean, polycrystalline α‐Th from background CO/CO2 and saturation of the Th surface by O2 has been examined by angle‐resolved Auger electron spectroscopy (ARAES) and time of flight secondary ion mass spectrometry (ToF‐SIMS). Following dissociative adsorption of very low doses of background CO/CO2 (<1 L), the carbon surface population was dominant and spontaneously formed thorium carbide. The accompanying oxygen population increased at a rate roughly one‐third that of the carbon, suggesting simultaneous oxygen incorporation into the bulk. To further corroborate the surface kinetics of adsorbed oxygen, O2 was admitted, following heating and sputter cleaning of the Th; some oxygen atoms continued to diffuse into the bulk until formation of stoichiometric ThO2 at ∼37 L. ARAES measurements showed an oxygen concentration gradient in the near‐surface region confirming rapid oxygen incorporation at low doses; however, once the surface is saturated, virtually no variation in the oxygen intensity is observed. AES and ToF‐SIMS depth profiling revealed complete oxide formation to a depth of 2 nm. Copyright © 2010 John Wiley & Sons, Ltd.
Interval estimation of the over‐dispersion parameter in the analysis of one‐way layout of count data
Authors: Saha Krishna K.
Published: September 2010

The over‐dispersion parameter is an important and versatile measure in the analysis of one‐way layout of count data in biological studies. For example, it is commonly used as an inverse measure of aggregation in biological count data. Its estimation from finite data sets is a recognized challenge. Many simulation studies have examined the bias and efficiency of different estimators of the over‐dispersion parameter for finite data sets (see, for example, Clark and Perry,Biometrics1989; 45:309–316 and Piegorsch,Biometrics1990; 46:863–867), but little attention has been paid to the accuracy of the confidence intervals (CIs) of it. In this paper, we first derive asymptotic procedures for the construction of confidence limits for the over‐dispersion parameter using four estimators that are specified by only the first two moments of the counts. We also obtain closed‐form asymptotic variance formulae for these four estimators. In addition, we consider the asymptotic CI based on the maximum likelihood (ML) estimator using the negative binomial model. It appears from the simulation results that the asymptotic CIs based on these five estimators have coverage below the nominal coverage probability. To remedy this, we also study the properties of the asymptotic CIs based on the restricted estimates of ML, extended quasi‐likelihood, and double extended quasi‐likelihood by eliminating the nuisance parameter effect using their adjusted profile likelihood and quasi‐likelihoods. It is shown that these CIs outperform the competitors by providing coverage levels close to nominal over a wide range of parameter combinations. Two examples to biological count data are presented. Copyright © 2010 John Wiley & Sons, Ltd.
Drug delivery: Layer‐By‐Layer‐Assembled Capsules and Films for Therapeutic Delivery (Small 17/2010)
Authors: Becker Alisa L. , Johnston Angus P. R. , Caruso Frank
Published: September 2010

Polymeric materials formed via layer‐by‐layer (LbL) assembly have promise for use as drug delivery vehicles. These multilayered materials, both as capsules and thin films, can encapsulate a high payload of toxic or sensitive drugs, and can be readily engineered and functionalized with specific properties. This review highlights important and recent studies that advance the use of LbL‐assembled materials as therapeutic devices. It also seeks to identify areas that require additional investigation for future development of the field. A variety of drug‐loading methods and delivery routes are discussed. The biological barriers to successful delivery are identified, and possible solutions to these problems are discussed. Finally, state‐of‐the‐art degradation and cargo release mechanisms are also presented.
Durchrutschende Grout‐Verbindungen in OWEA – Tragverhalten, Instandsetzung und Optimierung
Authors: Schaumann Peter , Lochte‐Holtgreven Stephan , Lohaus Ludger , Lindschulte Nick
Published: September 2010

Grout‐Verbindungen werden für die Verbindung zwischen den Gründungs‐ und Turmstrukturen von Offshore‐Windenergieanlagen (OWEA) vielfach eingesetzt. Insbesondere die seit Beginn der 90er Jahre im Meer installierten Windturbinen mit Monopile‐Gründung verfügen über diese hybride Verbindungskonstruktion, bei der Stahlzylinder mit glatter Mantelfläche übereinander gefädelt werden und der Zwischenraum mit hochfesten Feinkornmörteln vergossen wird. Bislang wurde auf eine spezielle Oberflächenprofilierung der Stahlrohre verzichtet. Während standardmäßiger Wartungsintervalle wurden nun an Rohr‐in‐Rohr‐Steckverbindungen in Monopiles in Dänemark, Großbritannien und den Niederlanden vertikale Verschiebungen festgestellt, die auf ein Versagen des Haftverbunds zwischen Stahl und Füllmaterial schließen lassen. Im Rahmen dieses Beitrags wird zunächst der Aufbau sowie das Trag‐ und Ermüdungsverhalten der Grout‐Verbindung erläutert und eigene Untersuchungen an diesen Verbindungen mit Ergebnissen präsentiert. Darauf aufbauend werden mögliche Gründe für die aufgetretenen Schäden diskutiert und Instandsetzungsvorschläge unterbreitet. Neben der Betrachtung der offshore‐spezifischen Einbaubedingungen werden die Maßnahmen hinsichtlich des technischen Aufwands vorgestellt und Kerbfallklassen für die Stahlbauteile zur Bestimmung der Materialermüdung präsentiert. Für zukünftige Gründungsstrukturen werden Optimierungsmöglichkeiten vorgestellt.

Sinking grouted joints in offshore wind turbines – Bearing behaviour, repair, and optimisation. Grouted joints are mainly used for the connection of foundation piles and substructures of offshore wind turbines. Grouted joints consist of tube‐to‐tubeconnections where the annulus is filled with a high performance mortar. Since the early 90s, grouted joints have been installed in offshore wind energy converters with monopiles using plain steel sections with no additional mechanical interlock. During maintenance work vertical slippages have been detected at substructures with monopiles in Denmark, UK and the Netherlands. The movements may result from a loss of bond between steel and mortar. Within this paper the construction and the bearing behaviour of grouted joints is presented. Additionally experimental investigations are shown. Based on own experiences reasons for failure and repair opportunities are introduced and optimisation opportunities for future turbines are proposed.
Cardiac intervention using high‐intensity focused ultrasound: creation of interatrial communication in beating heart of an anesthetized rabbit
Authors: Fujisaki M. , Chiba T. , Enosawa S. , Dohi T. , Takamoto S.
Published: September 2010

Objective

Current fetal cardiac intervention for restrictive atrial septum is invasive and technically demanding. We investigated the feasibility of computer‐assisted high‐intensity focused ultrasound (HIFU) for cardiac intervention on the atrial septum of a beating heart.

Methods

To create an interatrial communication in the beating heart of nine anesthetized rabbits, the heart was exposed surgically and placed under a water‐filled tank, in contact with the tank's membranous base. A HIFU transducer (3.3 MHz) coupled with a diagnostic ultrasound probe (10.0 MHz) was placed in the tank over the beating heart. The focus of the HIFU transducer was set so that it could create a hole in the target area on the atrial septum during the early diastolic phase. HIFU delivery was controlled based on ultrasound images captured with real‐time image‐recognition software. We attempted to create interatrial communication using HIFU and assessed the cardiac tissue specimen pathologically.

Results

In eight of nine rabbits, small holes in the atrial septum were successfully created. Serious complications occurred in two animals: a fatal atrioventricular block in one and a cardiac tamponade in the other.

Conclusion

HIFU combined with a computer‐assisted imaging system might be useful to create interatrial communication in beating hearts. This procedure may be helpful for making current fetal cardiac intervention less invasive. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Synthesis, Structural Characterization, and Catalytic Activity of Scandium, Samarium, and Dysprosium Complexes Supported by Tris(pyrrolyl‐α‐methyl)amine Ligand
Authors: Zhou Fengying , Wu Jing , Lin Miaoshui , Zhao Yang , Wu Jian , Zhang Yong , Li Wu , Li Yahong
Published: September 2010

The synthesis, structures and catalytic activities of three organolanthanide complexes supported by the H3tpa ligand (H3tpa = tris(pyrrolyl‐α‐methyl) amine) are described. Treatment of H3tpa with one equivalent of Ln[N(SiMe3)2]3 (Ln = Sc, Sm, Dy) in THF gives, after recrystallization from toluene/THF solution, Sc(tpa)(THF)2 (1), Sm(tpa)(THF)3 (2) and Dy(tpa)(THF)3 (3) in good yields. The structures of complexes 1–3 were determined by single‐crystal X‐ray diffraction and elemental analysis. Complexes 2 and 3 exhibited good catalytic activity for the polymerization of ϵ‐caprolactone.
The contribution of adhesion signaling to lactogenesis
Authors: Morrison Bethanie , Cutler Mary Lou
Published: September 2010

The mammary gland undergoes hormonally controlled cycles of pubertal maturation, pregnancy, lactation, and involution, and these processes rely on complex signaling mechanisms, many of which are controlled by cell–cell and cell–matrix adhesion. The adhesion of epithelial cells to the extracellular matrix initiates signaling mechanisms that have an impact on cell proliferation, survival, and differentiation throughout lactation. The control of integrin expression on the mammary epithelial cells, the composition of the extracellular matrix and the presence of secreted matricellular proteins all contribute to essential adhesion signaling during lactogenesis. In vitro and in vivo studies, including the results from genetically engineered mice, have shed light on the regulation of these processes at the cell and tissue level and have led to increased understanding of the essential signaling components that are regulated in temporal and cell specific manner during lactogenesis. Recent studies suggest that a secreted matricellular protein, CTGF/CCN2, may play a role in lactogenic differentiation through binding to β1 integrin complexes, enhancing the production of extracellular matrix components and contributions to cell adhesion signaling.
NEIGHBOURHOODS OF UNIVALENT FUNCTIONS
Authors: PASCU MIHAI N. , PASCU NICOLAE R.
Published: September 2010

The main result shows that a small perturbation of a univalent function is again a univalent function, hence a univalent function has a neighbourhood consisting entirely of univalent functions. For the particular choice of a linear function in the hypothesis of the main theorem, we obtain a corollary which is equivalent to the classical Noshiro–Warschawski–Wolff univalence criterion. We also present an application of the main result in terms of Taylor series, and we show that the hypothesis of our main result is sharp.
ON THE DENSITY TYPE TOPOLOGIES IN HIGHER DIMENSIONS
Authors: HORBACZEWSKA GRAŻYNA
Published: September 2010

The topologies of the density type in Euclidean space of dimension higher than one are introduced. Definitions are based on a notion of density point connected with a set of sequences of real numbers. Our purpose is to study properties of these topologies and connections between them.
SOME REMARKS ON PRINCIPAL PRIME IDEALS
Authors: ANDERSON D. D. , CHUN SANGMIN
Published: September 2010

In this paper we investigate principal prime ideals in commutative rings. Among other things we characterize the principal prime ideals that are both minimal and maximal and characterize the maximal ideals of a polynomial ring that are principal. Our main result is that if (p) is a principal prime ideal of an atomic ring R, then ht(p)≤1.
DECOMPOSING LINEAR TRANSFORMATIONS
Authors: WANG LU , ZHOU YIQIANG
Published: September 2010

Let R be the ring of linear transformations of a right vector space over a division ring D. Three results are proved: (1) if |D|>4, then for any a∈R there exists a unit u of R such that a+u,a−u and a−u−1 are units of R; (2) if |D|>3 , then for any a∈R there exists a unit u of R such that both a+u and a−u−1 are units of R; (3) if |D|>2 , then for any a∈R there exists a unit u of R such that both a−u and a−u−1 are units of R. The second result extends the main result in H. Chen, [‘Decompositions of countable linear transformations’, Glasg. Math. J. (2010), doi:10.1017/S0017089510000121] and the third gives an affirmative answer to the question raised in the same paper.
A waterborne Campylobacter jejuni outbreak on a Greek island
Authors: KARAGIANNIS I. , SIDEROGLOU T. , GKOLFINOPOULOU K. , TSOURI A. , LAMPOUSAKI D. , VELONAKIS E. N. , SCOULICA E. V. , MELLOU K. , PANAGIOTOPOULOS T. , BONOVAS S.
Published: September 2010

A case-control and a case-crossover study were performed to investigate a Campylobacter jejuni outbreak in Crete in 2009. Most cases originated from rural areas, served by a different water-supply system from that of the adjacent town. Thirty-seven cases and 79 controls were interviewed; cases were interviewed for two different time periods for the case-crossover study. Stool cultures, PFGE and MLST subtyping were run in human samples. Univariately, consumption of tap water was associated with C. jejuni infection. Stratified analysis revealed that water-supply system was an effect modifier of this association. In the multivariable analysis, the rural areas' water supplier and drinking tap water were risk factors. No risk factors were revealed in the case-crossover study. No Campylobacter were isolated in the tested water samples. There is strong epidemiological evidence that tap water was the vehicle of the outbreak.
George Augustus Selwyn, First Bishop of New Zealand and the Origins of the Anglican Communion
Authors: Jacob W.M.
Published: September 2010

This article aims to identify the significance of George Augustus Selwyn, the first Bishop of New Zealand, for the development of the Anglican Communion. It is based on evidence derived from secondary sources, most obviously the two-volume life of Selwyn written shortly after his death by his former chaplain, and on recent studies of the development of the Anglican Communion, especially the development of provincial synodical government in Australasia, and on the constitution of the Episcopal Church in the United States.

The article concludes that Selwyn had ideal qualities and experiences to enable him to achieve a constitution for a new Anglican province independent of the state, and with self-government, including elected representatives of laity and clergy, as well as bishops meeting together. His commitment to creating a constitutional framework for the dioceses and provinces of the Anglican Communion, including the Episcopal Church, enabled a second Lambeth Conference to happen.
Response of Arctic 1000 hPa circulation to changes in horizontal resolution and sea ice forcing in the Community Atmospheric Model
Authors: Higgins Matthew E. , Cassano John J.
Published: September 2010

Arctic winter surface atmospheric circulation biases inherent to the Community Atmospheric Model version 3 (CAM3) are examined with emphasis on the influence of horizontal resolution (T42, ∼2.8° versus T85, ∼1.4°). Using geopotential height at 1000 hPa (Z1000) to represent surface circulation, the self‐organizing map technique is used to better understand these biases from a synoptic climatology perspective. The previously documented low sea level pressure (SLP) bias over the Beaufort Sea, Canadian Archipelago, Greenland Sea, Norwegian Sea, and northern Europe and high SLP bias over the northern Pacific and Atlantic oceans are shown to result from an underprediction of weak Aleutian and Icelandic low patterns and an overprediction of strong Arctic low patterns, strong Icelandic low patterns, and patterns with pronounced ridges spanning the Arctic Ocean. Resolution‐caused differences are shown to be the result of CAM3 at T85 resolution predicting fewer strong Icelandic lows, North Atlantic lows, and strong high‐pressure ridges across the Arctic relative to CAM3 at T42 resolution. In addition, CAM3 at T85 resolution predicts more strong Arctic low patterns relative to CAM3 at T42 resolution. The ability of CAM3 at both resolutions to resolve mesoscale features such as polar lows near the sea ice edge is also explored. Despite these biases, CAM3 can still be used experimentally to examine atmospheric response to changing climatic conditions, particularly if results are viewed in the framework of a sensitivity study. With this in mind, the impact of future projections of sea ice on winter Arctic circulation is examined at both model resolutions. It is found that weak Arctic low patterns and strong Icelandic low patterns increase in frequency in the winter, while Aleutian/Icelandic low patterns and North Atlantic low/Pacific high patterns decrease in frequency in the winter with future projections of sea ice.
An improved limited area model for describing the dust cycle in the atmosphere
Authors: Spyrou C. , Mitsakou C. , Kallos G. , Louka P. , Vlastou G.
Published: September 2010

During the last decade, several numerical schemes have been deployed for the simulation of mineral dust processes in the atmosphere. The developed models have various deficiencies in the representation of dust particle physical properties and effects on climate. On the basis of the present status of the dust modeling tools, a combined effort was devoted to upgrading the SKIRON/Dust forecasting system by incorporating new features for the description of the lower boundary characteristics of the atmospheric model and the dust aerosol properties. In this paper, the updated model version is presented along with sensitivity simulations and evaluation of the model results with available observational data. The analysis is separated into two main parts, namely, the improvements that correspond to the atmospheric modeling system SKIRON and the upgrading of the physical mechanisms incorporated in the dust transport submodel. The analysis showed that the incorporation of the new model correction schemes led to a better and more accurate representation of the processes concerning meteorology and dust properties. The new soil characterization schemes significantly improve the energy‐partitioning predictions at the surface and therefore the boundary layer processes that play a substantial role in the determination of the dust production mechanisms. Significant differences were detected in the radiation balance between atmosphere and ground surface by incorporating statistical corrections for the description of terrain slopes and azimuths, mainly in areas with highly rough terrain. Finally, the more accurate description of the transported dust aerosol distribution (eight size bins) and the new dust production and deposition schemes led to more efficient determination of the dust particle optical properties (aerosol optical depths).
Psoriasis: from pathogenesis to novel therapeutic approaches
Authors: Monteleone Giovanni , Pallone Francesco , MacDonald Thomas T. , Chimenti Sergio , Costanzo Antonio
Published: September 2010

Psoriasis is one of the commonest chronic inflammatory disorders. Its cause is unknown, but a wealth of studies indicate that the disease results from a complex and dynamic interplay between genetic and environmental factors that trigger an excessive inflammatory response in the skin. Dendritic cells and effector T-cells are central in the development of the psoriastic lesion, and cytokines produced by these cells stimulate keratinocytes to proliferate and increase the migration of inflammatory cells into the skin, promoting epidermal hyperplasia and inflammation. Understanding the immunology of the psoriatic plaque has led to new therapeutic options and novel candidates for immunomodulation, and has changed the ways psoriatic patients are managed.
Adaptive Wavelength Calibration Algorithm for LAMOST
Authors: Qin H. Q. , Zhu J. , Zhu Z. Q. , Ye Z. F. , Luo A. L.
Published: September 2010

An adaptive algorithm is presented for the wavelength calibration of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). The new algorithm can identify emission lines of calibration lamp without manual interaction and then fit relationship between the pixel positions and the wavelengths by utilizing a polynomial function. In this study, experiments are performed both on the actual data observed by LAMOST and the simulated data to analyze the accuracy and the robustness.The experimental results show that the proposed automatic algorithm can perform the lines identification exactly and acquire the wavelength solution accurately. Thus, an applicable approach is provided for the wavelength calibration of LAMOST.
A Direct Detection of Gas Accretion: The Lyman Limit System in 3C 232
Authors: Stocke John T. , Keeney Brian A. , Danforth Charles W.
Published: September 2010

The gas added to and removed from galaxies over cosmic time greatly affects their stellar populations and star formation rates. QSO absorption line studies in close QSO/galaxy pairs create a unique opportunity to study the physical conditions and kinematics of this gas. Here we present new Hubble Space Telescope (HST) images of the QSO/galaxy pair, 3C 232/NGC 3067. The quasar spectrum contains a Lyman limit (NHi = 1 × 1020 cm−2) absorption system (LLS) at cz = 1421 km s−1 that is associated with the nearby Sab galaxy NGC 3067. Previous work identifies this absorber as a high-velocity cloud (HVC) in NGC 3067 but the kinematics of the absorbing gas, infalling or outflowing, were uncertain. The HST images presented here establish the orientation of NGC 3067 and so establish that the LLS/HVC is infalling. Using this system as a prototype, we extend these results to higher-z MgII/LLS to suggest that Mgii/LLSs are a sightline sampling of the so-called ‘cold mode accretion’ (CMA) infalling onto luminous galaxies. To match the observed MgII absorber statistics, the CMA must be more highly ionised at higher redshifts. The key observations needed to further the study of low-z LLSs is HST UV spectroscopy, for which a new instrument, the Cosmic Origins Spectrograph, has just been installed greatly enhancing our observational capabilities.
The Correlated Multi-color Optical Variations of BL Lac Object S5 0716+714
Authors: Zhang Bingkai , Dai Benzhong , Zhang Li , Liu Jiali , Cao Zhen
Published: September 2010

S5 0716+714 is a well-studied BL Lac object in the sky. Verifying the existence of correlations among the flux variations in different bands serves as an important tool to investigate the emission processes. To examine the possible existence of a lag between variations in different optical bands on this source, we employ a discrete correlation function analysis on the light curves. In order to obtain statistically meaningful values for the cross-correlation time lags and their related uncertainties, we perform Monte Carlo simulations called ‘flux redistribution/random subset selection’. Our analysis confirms that the variations in different optical light curves are strongly correlated. The time lags show a hint of the variations in high frequency band leading those in low frequency band of the order of a few minutes.
Establishment of HIV-1 latency in resting CD4
+
T cells depends on chemokine-induced changes in the actin cytoskeleton
Authors: Cameron Paul U. , Saleh Suha , Sallmann Georgina , Solomon Ajantha , Wightman Fiona , Evans Vanessa A. , Boucher Genevieve , Haddad Elias K. , Sekaly Rafick-Pierre , Harman Andrew N. , Anderson Jenny L. , Jones Kate L. , Mak Johnson , Cunningham Anthony L. , Jaworowski Anthony , Lewin Sharon R.
Published: September 2010

Eradication of HIV-1 with highly active antiretroviral therapy (HAART) is not possible due to the persistence of long-lived, latently infected resting memory CD4
+
T cells. We now show that HIV-1 latency can be established in resting CD4
+
T cells infected with HIV-1 after exposure to ligands for CCR7 (CCL19), CXCR3 (CXCL9 and CXCL10), and CCR6 (CCL20) but not in unactivated CD4
+
T cells. The mechanism did not involve cell activation or significant changes in gene expression, but was associated with rapid dephosphorylation of cofilin and changes in filamentous actin. Incubation with chemokine before infection led to efficient HIV-1 nuclear localization and integration and this was inhibited by the actin stabilizer jasplakinolide. We propose a unique pathway for establishment of latency by direct HIV-1 infection of resting CD4
+
T cells during normal chemokine-directed recirculation of CD4
+
T cells between blood and tissue.
Orientation saliency without visual cortex and target selection in archer fish
Authors: Mokeichev Alik , Segev Ronen , Ben-Shahar Ohad
Published: September 2010

Our visual attention is attracted by salient stimuli in our environment and affected by primitive features such as orientation, color, and motion. Perceptual saliency due to orientation contrast has been extensively demonstrated in behavioral experiments with humans and other primates and is believed to be facilitated by the functional organization of the primary visual cortex. In behavioral experiments with the archer fish, a proficient hunter with remarkable visual abilities, we found an orientation saliency effect similar to that observed in human subjects. Given the enormous evolutionary distance between humans and archer fish, our findings suggest that orientation-based saliency constitutes a fundamental building block for efficient visual information processing.
Rapid weight gain after birth predicts life history and reproductive strategy in Filipino males
Authors: Kuzawa Christopher W. , McDade Thomas W. , Adair Linda S. , Lee Nanette
Published: September 2010

Ecological cues during prenatal and postnatal development may allow organisms to adjust reproductive strategy. The hypothalamic-pituitary-gonadal (HPG) axis is a prime candidate for adaptive plasticity as a result of its critical period of birth to 6 mo (B6M) in humans and the role of testosterone in the development and maintenance of costly sexually dimorphic somatic and behavioral traits. We hypothesized that weight velocity specific to B6M would predict male life history characteristics, including maturational timing, reproductive hormones, adult size, strength, and sexual activity. Data come from 770 Filipino men (age 20.5–22.5 y) followed since birth, with predictor variables including birth weight and weight velocities calculated at 6-mo intervals during the first 2 y of life. As expected, infants who were breastfed experienced less diarrhea, lived in wealthier households with better hygiene, and grew faster from B6M. Males with rapid B6M growth reached puberty earlier and, as young adults, had higher testosterone levels, were taller, more muscular, and had higher grip strength. They also had sex earlier and were more likely to report having had sex in the past month, resulting in more lifetime sex partners. Relationships between B6M weight gain and physical outcomes were generally not present or weaker in female subjects. We conclude that rapid weight gain specific to the brief postnatal hypothalamic-pituitary-gonadal critical period predicts early maturation and sexual activity, elevated hormone production, and more costly adult somatic characteristics among the male subjects in this sample. These findings provide evidence for early life developmental plasticity in male life history and reproductive strategy in humans.
Nonneuronal cells regulate synapse formation in the vestibular sensory epithelium via erbB-dependent BDNF expression
Authors: Gómez-Casati Maria E. , Murtie Joshua C. , Rio Carlos , Stankovic Konstantina , Liberman M. Charles , Corfas Gabriel
Published: September 2010

Recent studies indicate that molecules released by glia can induce synapse formation. However, what induces glia to produce such signals, their identity, and their in vivo relevance remain poorly understood. Here we demonstrate that supporting cells of the vestibular organ—cells that have many characteristics of glia—promote synapse formation only when induced by neuron-derived signals. Furthermore, we identify BDNF as the synaptogenic signal produced by these nonneuronal cells. Mice in which erbB signaling has been eliminated in supporting cells have vestibular dysfunction caused by failure of synapse formation between hair cells and sensory neurons. This phenotype correlates with reduced BDNF expression in supporting cells and is rescued by reexpression of BDNF in these cells. Furthermore, knockdown of BDNF expression in supporting cells postnatally phenocopies the loss of erbB signaling. These results indicate that vestibular supporting cells contribute in vivo to vestibular synapse formation and that this is mediated by reciprocal signals between sensory neurons and supporting cells involving erbB receptors and BDNF.
Shared molecular amino acid signature in the HLA-DR peptide binding pocket predisposes to both autoimmune diabetes and thyroiditis
Authors: Menconi Francesca , Osman Roman , Monti Maria C. , Greenberg David A. , Concepcion Erlinda S. , Tomer Yaron
Published: September 2010

There is strong genetic association between type 1A diabetes (T1D) and autoimmune thyroid disease (AITD). T1D and AITD frequently occur together in the same individual, a condition classified as a variant of the autoimmune polyglandular syndrome type 3 (APS3). Because T1D and AITD are individually strongly associated with different HLA class II sequences, we asked which HLA class II pocket sequence and structure confer joint susceptibility to both T1D and AITD in the same individual (APS3v). We sequenced the HLA-DR gene in 105 APS3v patients and 153 controls, and identified a pocket amino acid signature, DRβ-Tyr-26, DRβ-Leu-67, DRβ-Lys-71, and DRβ-Arg-74, that was strongly associated with APS3v (
P
= 5.4 × 10
−14
, odds ratio = 8.38). Logistic regression analysis demonstrated that DRβ-Leu-67 (
P
= 9.4 × 10
−13
) and DRβ-Arg-74 (
P
= 1.21 × 10
−13
) gave strong independent effects on disease susceptibility. Structural modeling studies demonstrated that pocket 4 was critical for the development of T1D+AITD; all disease-associated amino acids were linked to areas of the pocket that interact directly with the peptide and, therefore, influence peptide binding. The disease-susceptible HLA-DR pocket was more positively charged (Lys-71, Arg-74) compared with the protective pocket (Ala-71, Gln-74). We conclude that a specific pocket amino acid signature confers joint susceptibility to T1D+AITD in the same individual by causing significant structural changes in the MHC II peptide binding pocket and influencing peptide binding and presentation. Moreover, Arg-74 is a major amino acid position for the development of several autoimmune diseases. These findings suggest that blocking the critical Arg-74 pocket might offer a method for treating certain autoimmune conditions.
Trapping and spectroscopic characterization of an FeIII-superoxo intermediate from a nonheme mononuclear iron-containing enzyme
Authors: Mbughuni Michael M. , Chakrabarti Mrinmoy , Hayden Joshua A. , Bominaar Emile L. , Hendrich Michael P. , Münck Eckard , Lipscomb John D.
Published: September 2010

intermediates are well known in heme enzymes, but none have been characterized in the nonheme mononuclear FeIIenzyme family. Many steps in the O2activation and reaction cycle of FeII-containing homoprotocatechuate 2,3-dioxygenase are made detectable by using the alternative substrate 4-nitrocatechol (4NC) and mutation of the active site His200 to Asn (H200N). Here, the first intermediate (Int-1) observed after adding O2to the H200N-4NC complex is trapped and characterized using EPR and Mössbauer (MB) spectroscopies. Int-1 is a high-spin (S1 = 5/2) FeIIIantiferromagnetically (AF) coupled to anS2 = 1/2 radical (J ≈ 6 cm-1in). It exhibits parallel-mode EPR signals atg = 8.17 from theS = 2 multiplet, andg = 8.8 and 11.6 from theS = 3 multiplet. These signals are broadened significantly byhyperfine interactions (A17O ≈ 180 MHz). Thus, Int-1 is an AF-coupledspecies. The experimental observations are supported by density functional theory calculations that show nearly complete transfer of spin density to the bound O2. Int-1 decays to form a second intermediate (Int-2). MB spectra show that it is also an AF-coupled FeIII-radical complex. Int-2 exhibits an EPR signal atg = 8.05 arising from anS = 2 state. The signal is only slightly broadened by(< 3% spin delocalization), suggesting that Int-2 is a peroxo-FeIII-4NC semiquinone radical species. Our results demonstrate facile electron transfer between FeII, O2, and the organic ligand, thereby supporting the proposed wild-type enzyme mechanism.
Regional aerobic glycolysis in the human brain
Authors: Vaishnavi S. Neil , Vlassenko Andrei G. , Rundle Melissa M. , Snyder Abraham Z. , Mintun Mark A. , Raichle Marcus E.
Published: September 2010

Aerobic glycolysis is defined as glucose utilization in excess of that used for oxidative phosphorylation despite sufficient oxygen to completely metabolize glucose to carbon dioxide and water. Aerobic glycolysis is present in the normal human brain at rest and increases locally during increased neuronal activity; yet its many biological functions have received scant attention because of a prevailing energy-centric focus on the role of glucose as substrate for oxidative phosphorylation. As an initial step in redressing this neglect, we measured the regional distribution of aerobic glycolysis with positron emission tomography in 33 neurologically normal young adults at rest. We show that the distribution of aerobic glycolysis in the brain is differentially present in previously well-described functional areas. In particular, aerobic glycolysis is significantly elevated in medial and lateral parietal and prefrontal cortices. In contrast, the cerebellum and medial temporal lobes have levels of aerobic glycolysis significantly below the brain mean. The levels of aerobic glycolysis are not strictly related to the levels of brain energy metabolism. For example, sensory cortices exhibit high metabolic rates for glucose and oxygen consumption but low rates of aerobic glycolysis. These striking regional variations in aerobic glycolysis in the normal human brain provide an opportunity to explore how brain systems differentially use the diverse cell biology of glucose in support of their functional specializations in health and disease.
Spatial correlation between brain aerobic glycolysis and amyloid-β (Aβ) deposition
Authors: Vlassenko Andrei G. , Vaishnavi S. Neil , Couture Lars , Sacco Dana , Shannon Benjamin J. , Mach Robert H. , Morris John C. , Raichle Marcus E. , Mintun Mark A.
Published: September 2010

Amyloid-β (Aβ) plaque deposition can precede the clinical manifestations of dementia of the Alzheimer type (DAT) by many years and can be associated with changes in brain metabolism. Both the Aβ plaque deposition and the changes in metabolism appear to be concentrated in the brain's default-mode network. In contrast to prior studies of brain metabolism which viewed brain metabolism from a unitary perspective that equated glucose utilization with oxygen consumption, we here report on regional glucose use apart from that entering oxidative phosphorylation (so-called “aerobic glycolysis”). Using PET, we found that the spatial distribution of aerobic glycolysis in normal young adults correlates spatially with Aβ deposition in individuals with DAT and cognitively normal participants with elevated Aβ, suggesting a possible link between regional aerobic glycolysis in young adulthood and later development of Alzheimer pathology.
The Plant Homeo Domain finger protein, VIN3-LIKE 2, is necessary for photoperiod-mediated epigenetic regulation of the floral repressor, MAF5
Authors: Kim Dong-Hwan , Sung Sibum
Published: September 2010

In facultative photoperiodic flowering plants, noninductive photoperiods result in a delay in flowering, but such plants eventually flower, illustrating plasticity in an important developmental transition, flowering. The model plant,
Arabidopsis
, has a facultative photoperiod response. Although the inductive flowering promotion pathway has been extensively studied, the pathway to flowering in noninductive photoperiods is not well understood. Here, we show that a Plant Homeo Domain finger-containing protein, VIN3-LIKE 2 (VIL2), is necessary to maintain the epigenetically repressed state of
MAF5
and permit more rapid flowering in noninductive photoperiods in
Arabidopsis
. Levels of both VIL2 mRNA and protein are under diurnal fluctuation and maintain the repressed state at
MAF5
chromatin in a photoperiod-specific manner. VIL2 binds preferentially to dimethylated histone H3 Lys-9 (H3K9me2) peptides in vitro and VIL2 is required for the maintenance of H3K9me2 at
MAF5
chromatin in vivo. Furthermore,
VIL2
is required for the maintenance of trimethylated histone H3 Lys-27 at
MAF5
through the physical association with a component of polycomb repression complex 2. Thus, the repression of
MAF5
by
VIL2
provides a mechanism to promote flowering in noninductive photoperiods, which contributes to the facultative nature of the
Arabidopsis
photoperiodic response.
Navigating transformations in governance of Chilean marine coastal resources
Authors: Gelcich Stefan , Hughes Terry P. , Olsson Per , Folke Carl , Defeo Omar , Fernández Miriam , Foale Simon , Gunderson Lance H. , Rodríguez-Sickert Carlos , Scheffer Marten , Steneck Robert S. , Castilla Juan C.
Published: September 2010

Marine ecosystems are in decline. New transformational changes in governance are urgently required to cope with overfishing, pollution, global changes, and other drivers of degradation. Here we explore social, political, and ecological aspects of a transformation in governance of Chile's coastal marine resources, from 1980 to today. Critical elements in the initial preparatory phase of the transformation were (
i
) recognition of the depletion of resource stocks, (
ii
) scientific knowledge on the ecology and resilience of targeted species and their role in ecosystem dynamics, and (
iii
) demonstration-scale experimental trials, building on smaller-scale scientific experiments, which identified new management pathways. The trials improved cooperation among scientists and fishers, integrating knowledge and establishing trust. Political turbulence and resource stock collapse provided a window of opportunity that triggered the transformation, supported by new enabling legislation. Essential elements to navigate this transformation were the ability to network knowledge from the local level to influence the decision-making processes at the national level, and a preexisting social network of fishers that provided political leverage through a national confederation of artisanal fishing collectives. The resultant governance scheme includes a revolutionary national system of marine tenure that allocates user rights and responsibilities to fisher collectives. Although fine tuning is necessary to build resilience of this new regime, this transformation has improved the sustainability of the interconnected social–ecological system. Our analysis of how this transformation unfolded provides insights into how the Chilean system could be further developed and identifies generalized pathways for improved governance of marine resources around the world.
Anti-inflammatory protein TSG-6 reduces inflammatory damage to the cornea following chemical and mechanical injury
Authors: Oh Joo Youn , Roddy Gavin W. , Choi Hosoon , Lee Ryang Hwa , Ylöstalo Joni H. , Rosa Robert H. , Prockop Darwin J.
Published: September 2010

Previous reports demonstrated that adult stem/progenitor cells from bone marrow (multipotent mesenchymal stem cells; MSCs) can repair injured tissues with little evidence of engraftment or differentiation. In exploring this phenomenon, our group has recently discovered that the therapeutic benefits of MSCs are in part explained by the cells being activated by signals from injured tissues to express an anti-inflammatory protein TNF-α–stimulated gene/protein 6 (TSG-6). Therefore, we elected to test the hypothesis that TSG-6 would have therapeutic effects in inflammatory but noninfectious diseases of the corneal surface. We produced a chemical and mechanical injury of the cornea in rats by brief application of 100% ethanol followed by mechanical debridement of corneal and limbal epithelium. Recombinant human TSG-6 or PBS solution was then injected into the anterior chamber of the eye. TSG-6 markedly decreased corneal opacity, neovascularization, and neutrophil infiltration. The levels of proinflammatory cytokines, chemokines, and matrix metalloproteinases were also decreased. The data indicated that TSG-6, a therapeutic protein produced by MSCs in response to injury signals, can protect the corneal surface from the excessive inflammatory response following injury.
Selective impairment of masked priming in dual-task performance
Authors: Fischer Rico , Kiesel Andrea , Kunde Wilfried , Schubert Torsten
Published: September 2010

This study investigated the impact of divided attention on masked priming. In a dual-task setting, two tasks had to be carried out in close temporal succession: a tone discrimination task and a masked priming task. The order of the tasks was varied between experiments, and attention was always allocated to the first task—that is, the first task was prioritized. The priming task was the second (nonprioritized) task in Experiment 1 and the first (prioritized) task in Experiment 2. In both experiments, “novel” prime stimuli associated with semantic processing were essentially ineffective. However, there was intact priming by another type of prime stimuli associated with response priming. Experiment 3 showed that all these prime stimuli can reveal significant priming effects during a task-switching paradigm in which both tasks were performed consecutively. We conclude that dual-task specific interference processes (e.g., the simultaneous coordination of multiple stimulus–response rules) selectively impair priming that is assumed to rely on semantic processing.
Stop being neutral: Simon takes control!
Authors: Aisenberg Daniela , Henik Avishai
Published: September 2010

The Simon task is one of the well known tasks that recruit cognitive control. The Simon effect, the reaction time (RT) difference between congruent and incongruent stimuli, has been commonly discussed as interference based. Nevertheless, in recent years some studies have referred to the facilitation component of the task. In the current research we measured effects of cognitive control by conducting sequential analysis and adding neutral conditions. Two neutral stimuli were employed in order to examine their effect and their validity as neutrals. It was found that presentation of Simon stimuli on the central meridian at the top or bottom of a screen (but not at the centre of the screen) created a valid neutral condition. Facilitation as well as interference effects were found. Adding a nonconflict condition modulated cognitive control independently of sequential effects. Namely, the Simon effect increased by adding both types of neutrals, but the decrease in the effect after incongruent trials was only present for the vertical neutral block, in which the Simon effect appeared after congruent but not after incongruent trials. We suggest the possibility of two different mechanisms of cognitive control.
Phosphoinositide 3-kinase δ regulates membrane fission of Golgi carriers for selective cytokine secretion
Authors: Low Pei Ching , Misaki Ryo , Schroder Kate , Stanley Amanda C. , Sweet Matthew J. , Teasdale Rohan D. , Vanhaesebroeck Bart , Meunier Frédéric A. , Taguchi Tomohiko , Stow Jennifer L.
Published: September 2010

Phosphoinositide 3-kinase (PI3K) p110 isoforms are membrane lipid kinases classically involved in signal transduction. Lipopolysaccharide (LPS)-activated macrophages constitutively and abundantly secrete proinflammatory cytokines including tumor necrosis factor-α (TNF). Loss of function of the p110δ isoform of PI3K using inhibitors, RNA-mediated knockdown, or genetic inactivation in mice abolishes TNF trafficking and secretion, trapping TNF in tubular carriers at the trans-Golgi network (TGN). Kinase-active p110δ localizes to the Golgi complex in LPS-activated macrophages, and TNF is loaded into p230-labeled tubules, which cannot undergo fission when p110δ is inactivated. Similar blocks in fission of these tubules and in TNF secretion result from inhibition of the guanosine triphosphatase dynamin 2. These findings demonstrate a new function for p110δ as part of the membrane fission machinery required at the TGN for the selective trafficking and secretion of cytokines in macrophages.