bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐similar earthquake triggering, Båth's law, and foreshock/aftershock magnitudes: Simulations, theory, and results for southern California
Authors: Shearer Peter M.
Published: May 2012

Båth's law, the observation that the largest aftershock is, on average, 1.2 magnitudes smaller than its main shock, independent of main shock size, suggests some degree of self‐similarity in earthquake triggering. This behavior can largely be explained with triggering models in which the increased triggering caused by larger magnitude events is exactly compensated for by their decreased numbers, and these models can account for many features of real seismicity catalogs. The Båth's law magnitude difference of 1.2 places a useful constraint on aftershock productivity in these models. A more general test of triggering self‐similarity is to plot foreshock and aftershock rates as a function of magnitude m relative to the main shock magnitude, mmax, of the largest event in the sequence. Both computer simulations and theory show that these dN/dm curves should be nearly coincident, regardless of main shock magnitude. The aftershock dN/dm curves have the same Gutenberg‐Richter b‐value as the underlying distribution, but the foreshock dN/dm curves have the same b‐value only for foreshock magnitudes less than about mmax − 3. For larger foreshock values, the dN/dm curve flattens and converges with the aftershock dN/dm curve at m = mmax. This effect can explain observations of anomalously low b‐values in some foreshock sequences and the decrease in apparent aftershock to foreshock ratios for small magnitude main shocks. Observed apparent foreshock and aftershock dN/dm curves for events close in space and time to M 2.5 to 5.5 main shocks in southern California appear roughly self‐similar, but differ from triggering simulations is several key respects: (1) the aftershock b‐values are significantly lower than that of the complete catalog, (2) the number of aftershocks is too large to be consistent with Båth's law, and (3) the foreshock‐to‐aftershock ratio is too large to be consistent with Båth's law. These observations indicate for southern California that triggering self‐similarity is not obeyed for these small main shocks or that the space/time clustering is not primarily caused by earthquake‐to‐earthquake triggering.
Integrating different types of information into hydrological model parameter estimation: Application to ungauged catchments and land use scenario analysis
Authors: Bulygina Nataliya , Ballard Caroline , McIntyre Neil , O'Donnell Greg , Wheater Howard
Published: May 2012

In hydrological modeling, two areas of application present particular challenges, first the modeling of ungauged catchments, and second the modeling of catchment nonstationarity; for example due to effects of land use change. The ungauged catchment problem requires that prior knowledge of the catchment is combined with evidence of behavior; for example from a regionalization exercise and/or spot flow measurements. Simulation of the effects of land use change requires that prior knowledge of the catchment is combined with information on the effects of that change on model parameters, generally in the absence of direct observations with which to condition the parameters. In both cases, ideally, all available sources of information about the behavior should be considered, and integrated in a way that maximizes the value of the information for model identification and uncertainty estimation. Using a formal Bayesian procedure, we combine three different sources of knowledge into a catchment scale conceptual model: (1) small‐scale physical properties; (2) regionalized signatures of flow; and (3) available flow measurements. Applying the methodology to a distributed model for the Hodder catchment, UK, the physics‐based information source contributed most to improving model performance, followed by peak flow times, and lastly the regionalized signatures. The flood frequency curve was evaluated under scenarios of land use change, and those changes that were significant relative to model uncertainty were identified.
Robust streamline tracing using inter‐cell fluxes in locally refined and unstructured grids
Authors: Zhang Y. , King M. J. , Datta‐Gupta A.
Published: May 2012

We present a comprehensive study of velocity interpolation methods in polygons. These methods are often used as postprocessing procedures for numerical schemes that do not directly calculate the velocity field but only provide cell boundary flux conditions, such as the finite volume schemes. These methods extend the widely used velocity interpolation algorithms, such as the Pollock's algorithm, to more complex geometries such as perpendicular bisection (PEBI) grids, unstructured triangular grids and grids with local refinement. Once the velocity field is interpolated, streamline trajectories and time of flight along the streamlines can be calculated for reservoir simulation, model calibration and waterflood management, for instance. These velocity interpolation methods assume known lower‐order or higher‐order cell boundary fluxes, which satisfy global mass conservation and normal flux continuity. However, they differ in the interpolation of velocities within the interior of the cells. The interpolating velocity may be locally conservative or nonconservative, continuous or discontinuous, lower order or higher order. Results show that the interpolated velocity field has to be locally conservative in order to guarantee the correct volumetric transformation for the calculated streamlines and the time of flight. Velocity continuity is not as important as local conservation for the purpose of streamline applications. Compared to higher‐order interpolation for the streamline trajectories, lower‐order interpolation has the advantage of an analytic solution and an efficient implementation. Based on our analysis, we recommend a lower‐order locally conservative method for the most robust and numerically efficient calculation of streamline trajectories on unstructured grids.
Entropy‐copula method for single‐site monthly streamflow simulation
Authors: Hao Z. , Singh V. P.
Published: May 2012

An entropy‐copula method is proposed for single‐site monthly streamflow simulation. In this method, the joint distribution of adjacent monthly streamflows is constructed using the copula method, whereas the marginal distribution of streamflow for each month is derived using the entropy method. Then, the conditional distribution is derived from which monthly streamflow is generated. Moment statistics of monthly streamflow (such as mean, standard deviation and skewness) can be modeled by the entropy‐based marginal distribution while the dependence structure between streamflows of adjacent months can be modeled by the copula‐based joint distribution. The proposed entropy‐copula method can be extended by incorporating an aggregate variable for modeling the interannual dependence. Application to the simulation of monthly streamflow from the Colorado River illustrates the effectiveness of the proposed method.
South China Sea throughflow impact on the Indonesian throughflow
Authors: Gordon Arnold L. , Huber Bruce A. , Metzger E. Joseph , Susanto R. Dwi , Hurlburt Harley E. , Adi T. Rameyo
Published: May 2012

In 2008–2009 the Makassar throughflow profile changed dramatically: the characteristic thermocline velocity maximum increased from 0.7 to 0.9 m/sec and shifted from 140 m to 70 m, amounting to a 47% increase in the transport of warmer water between 50 and 150 m during the boreal summer. HYCOM output indicates that ENSO induced change of the South China Sea (SCS) throughflow into the Indonesian seas is the likely cause. Increased SCS throughflow during El Niño with a commensurate increase in the southward flow of buoyant surface water through the Sulu Sea into the northern Makassar Strait, inhibits tropical Pacific surface water injection into Makassar Strait; during La Niña SCS throughflow is near zero allowing tropical Pacific inflow. The resulting warmer ITF reaches into the Indian Ocean, potentially affecting regional sea surface temperature and climate.
Statistical evidence for the natural variation of the central Pacific El Niño
Authors: Kim Jin‐Soo , Kim Kwang‐Yul , Yeh Sang‐Wook
Published: May 2012

Extensive studies claimed that the central equatorial Pacific (CP) El Niño has occurred more frequently and strongly than the eastern equatorial Pacific El Niño in recent years. To explain this phenomenon, spatial patterns and principal component time series from several sea surface temperature (SST) data sets in the tropical Pacific are analyzed for the period of 1951–2010. Cyclostationary empirical orthogonal function analysis separates two modes of SST variability, which explain about 50% and 10% of the total SST variability, respectively. Their spatial and temporal patterns are similar among the different SST data sets. The first mode captures the typical El Niño pattern, while the second mode is a dipole pattern in the tropical Pacific. The two modes are, by definition, uncorrelated over the analysis period but are in phase since the late 1990s; superposition of the two modes results in a significant warming in the CP region, which is a potential explanation for a more frequent occurrence of the CP El Niño in the recent decades. Similar analysis is conducted based on the 500 year data from the Geophysical Fluid Dynamics Laboratory Climate Model version 2.1 under the preindustrial condition. The result is generally consistent with the observations yielding occasional in‐phase relationship between the two modes. Thus, it cannot be ruled out that a more frequent occurrence of the CP El Niño in recent years is a natural feature of the equatorial climate system.
Quantifying soil surface change in degraded drylands: Shrub encroachment and effects of fire and vegetation removal in a desert grassland
Authors: Sankey Joel B. , Ravi Sujith , Wallace Cynthia S. A. , Webb Robert H. , Huxman Travis E.
Published: May 2012

Woody plant encroachment, a worldwide phenomenon, is a major driver of land degradation in desert grasslands. Woody plant encroachment by shrub functional types ultimately leads to the formation of a patchy landscape with fertile shrub patches interspaced with nutrient‐depleted bare soil patches. This is considered to be an irreversible process of land and soil degradation. Recent studies have indicated that in the early stages of shrub encroachment, when there is sufficient herbaceous connectivity, fires (prescribed or natural) might provide some reversibility to the shrub encroachment process by negatively affecting shrub demography and homogenizing soil resources across patches within weeks to months after burning. A comprehensive understanding of longer term changes in microtopography and spatial patterning of soil properties following fire in shrub‐encroached grasslands is desirable. Here, we investigate the changes in microtopography with LiDAR (light detection and ranging), vegetation recovery, and spatial pattering of soil properties in replicated burned, clipped, and control areas in a shrub‐grass transition zone in the northern Chihuahuan Desert four years after prescribed fire or clipping. Results indicate a greater homogeneity in soil, microtopography, and vegetation patterning on burned relative to clipped and control treatments. Findings provide further evidence that disturbance by prescribed fire may allow for reversal of the shrub encroachment process, if the event occurs in the early stages of the vegetation shift. Improved understanding of longer‐term effects of fire and associated changes in soil patterning can inform the use and role of fire in the context of changing disturbance regimes and climate.
Blocking of Bradykinin Receptor B1 Protects from Focal Closed Head Injury in Mice by Reducing Axonal Damage and Astroglia Activation
Authors: Albert-Weissenberger Christiane , Stetter Christian , Meuth Sven G , Göbel Kerstin , Bader Michael , Sirén Anna-Leena , Kleinschnitz Christoph
Published: May 2012

The two bradykinin receptors B1R and B2R are central components of the kallikrein–kinin system with different expression kinetics and binding characteristics. Activation of these receptors by kinins triggers inflammatory responses in the target organ and in most situations enhances tissue damage. We could recently show that blocking of B1R, but not B2R, protects from cortical cryolesion by reducing inflammation and edema formation. In the present study, we investigated the role of B1R and B2R in a closed head model of focal traumatic brain injury (TBI; weight drop). Increased expression of B1R in the injured hemispheres of wild-type mice was restricted to the later stages after brain trauma, i.e. day 7 ( P<0.05), whereas no significant induction could be observed for the B2R ( P>0.05). Mice lacking the B1R, but not the B2R, showed less functional deficits on day 3 ( P<0.001) and day 7 ( P<0.001) compared with controls. Pharmacological blocking of B1R in wild-type mice had similar effects. Reduced axonal injury and astroglia activation could be identified as underlying mechanisms, while inhibition of B1R had only little influence on the local inflammatory response in this model. Inhibition of B1R may become a novel strategy to counteract trauma-induced neurodegeneration.
Brain Response to Food Stimulation in Obese, Normal Weight, and Successful Weight Loss Maintainers
Authors: Sweet Lawrence H. , Hassenstab Jason J. , McCaffery Jeanne M. , Raynor Hollie A. , Bond Dale S. , Demos Kathryn E. , Haley Andreana P. , Cohen Ronald A. , Parigi Angelo D. , Wing Rena R.
Published: May 2012

As many people struggle with maintenance of weight loss, the study of successful weight loss maintainers (SWLM) can yield important insights into factors contributing to weight loss maintenance. However, little research has examined how SWLM differ from people who are obese or normal weight (NW) in brain response to orosensory stimulation. The goal of this study was to determine if SWLM exhibit different brain responses to orosensory stimulation. Brain response to 1‐min orosensory stimulation with a lemon lollipop was assessed using functional magnetic resonance imaging among 49 participants, including SWLM (n = 17), NW (n = 18), and obese (n = 14) controls. Significant brain responses were observed in nine brain regions, including the bilateral insula, left inferior frontal gyrus, left putamen, and other sensory regions. All regions also exhibited significant attenuation of this response over 1 min. The SWLM exhibited greater response compared with the other groups in all brain regions. Findings suggest that the response to orosensory stimulation peaks within 40 s and attenuates significantly between 40 and 60 s in regions associated with sensation, reward, and inhibitory control. Greater reactivity among the SWLM suggests that greater sensory reactivity to orosensory stimulation, increased anticipated reward, and subsequently greater inhibitory processing are associated with weight loss maintenance.
Inhibition of XO or NOX attenuates diethylstilbestrol-induced endothelial nitric oxide deficiency without affecting its effects on LNCaP cell invasion and apoptosis
Authors: Youn Ji-Youn , Nguyen Andrew , Cai Hua
Published: May 2012

Oestrogen protects cardiovascular health partially via an up-regulation of NO• (NO radical) production. Its synthetic analogue DES (diethylstilbestrol), used as a potent androgen deprivation therapy for patients with prostate cancer, is however associated with high incidence of thromboembolic events. Exposure of BAECs (bovine aortic endothelial cells) to pharmacologically relevant dosage (12.5 μmol/l, 24 h) of DES resulted in a marked reduction in endothelial NO• bioavailability determined by ESR (electron spin resonance), while 17β-oestradiol instead increased NO• production as expected. Intriguingly, endothelial O2•− (superoxide anion) production was up-regulated by DES in vitro and in vivo, which was, however, attenuated by the ER (oestrogen receptor) antagonist ICI 182780, the XO (xanthine oxidase) inhibitor oxypurinol or the NOX (NADPH oxidase) inhibitor NSC23766. These agents also restored NO• production. DES alone in a cell-free system did not produce any ESR-sound O2•− signal. Of note, eNOS (endothelial NO synthase) mRNA and protein remained unchanged in response to DES. These results suggest that receptor-dependent activation of XO or NOX, and subsequent production of O2•−, mediate DES-induced NO• deficiency. This could represent a previously unrecognized mechanism that is responsible for cardiovascular complications of DES administration. Importantly, DES-induced suppression of LNCaP cell invasion and apoptosis were not affected by XO or NOX inhibitor. Therefore combinatorial therapy of DES and XO/NOX inhibitor may prove to be an innovative and useful therapeutic option in eliminating cardiovascular complications of DES, while preserving its anti-cancer effects, benefiting patients with advanced cancer who do not respond well to any other treatments but DES.
Red wine extract protects against oxidative-stress-induced endothelial senescence
Authors: Botden Ilse P. G. , Oeseburg Hisko , Durik Matej , Leijten Frank P. J. , Van Vark-Van Der Zee Leonie C. , Musterd-Bhaggoe Usha M. , Garrelds Ingrid M. , Seynhaeve Ann L. B. , Langendonk Janneke G. , Sijbrands Eric J. G. , Danser A. H. Jan , Roks Anton J. M.
Published: May 2012

Red wine polyphenols may preserve endothelial function during aging. Endothelial cell senescence enhances age-related endothelial dysfunction. We investigated whether RWE (red wine extract) prevents oxidative-stress-induced senescence in HUVECs (human umbilical-vein endothelial cells). Senescence was induced by exposing HUVECs to tBHP (t-butylhydroperoxide), and quantified by senescence-associated β-galactosidase staining. RWE (0–50 μg/ml) concentration dependently decreased senescence by maximally 33±7.1%. RWE prevented the senescence-associated increase in p21 protein expression, inhibited tBHP-induced DNA damage of endothelial cells and induced relaxation of PCAs (porcine coronary arteries). Inhibition of SIRT1 (sirtuin 1) by sirtinol partially reversed the effect of RWE on tBHP-induced senescence, whereas both the NOS (nitric oxide synthase) inhibitor L-NMMA (NG-monomethyl-L-arginine) and the COX (cyclo-oxygenase) inhibitor indomethacin fully inhibited it. Furthermore, incubation of HUVECs with RWE increased eNOS (endothelial NOS) and COX-2 mRNA levels as well as phosphorylation of eNOS at Ser1177. RWE protects endothelial cells from tBHP-induced senescence. NO and COX-2, in addition to activation of SIRT1, play a critical role in the inhibition of senescence induction in human endothelial cells by RWE.
Looking at Op Art: Gaze Stability and Motion Illusions
Authors: Hermens Frouke , Zanker Johannes
Published: May 2012

Various Op artists have used simple geometrical patterns to create the illusion of motion in their artwork. One explanation for the observed illusion involves retinal shifts caused by small involuntary eye movements that observers make while they try to maintain fixation. Earlier studies have suggested a prominent role of the most conspicuous of these eye movements, small rapid position shifts called microsaccades. Here, we present data that could expand this view with a different interpretation. In three experiments, we recorded participants' eye movements while they tried to maintain visual fixation when being presented with variants of Bridget Riley's Fall, which were manipulated such as to vary the strength of induced motion. In the first two experiments, we investigated the properties of microsaccades for a set of stimuli with known motion strengths. In agreement with earlier observations, microsaccade rates were unaffected by the stimulus pattern and, consequently, the strength of induced motion illusion. In the third experiment, we varied the stimulus pattern across a larger range of parameters and asked participants to rate the perceived motion illusion. The results revealed that motion illusions in patterns resembling Riley's Fall are perceived even in the absence of microsaccades, and that the reported strength of the illusion decreased with the number of microsaccades in the trial. Together, the three experiments suggest that other sources of retinal image instability than microsaccades, such as slow oculomotor drift, should be considered as possible factors contributing to the illusion.
Perceptual Organization of Shape, Color, Shade, and Lighting in Visual and Pictorial Objects
Authors: Pinna Baingio
Published: May 2012

The main questions we asked in this work are the following: Where are representations of shape, color, depth, and lighting mostly located? Does their formation take time to develop? How do they contribute to determining and defining a visual object, and how do they differ? How do visual artists use them to create objects and scenes? Is the way artists use them related to the way we perceive them? To answer these questions, we studied the microgenetic development of the object perception and formation. Our hypothesis is that the main object properties are extracted in sequential order and in the same order that these roles are also used by artists and children of different age to paint objects. The results supported the microgenesis of object formation according to the following sequence: contours, color, shading, and lighting.
How Simultaneous is the Perception of Binocular Depth and Rivalry in Plaid Stimuli?
Authors: Buckthought Athena , Mendola Janine D
Published: May 2012

Psychophysical experiments have demonstrated that it is possible to perceive both binocular depth and rivalry in plaids (Buckthought and Wilson 2007, Vision Research 47 2543–2556). In a recent study, we investigated the neural substrates for depth and rivalry processing with these plaid patterns, when either a depth or rivalry task was performed (Buckthought and Mendola 2011, Journal of Vision 11 1–15). However, the extent to which perception of the two stimulus aspects was truly simultaneous remained somewhat unclear. In the present study, we introduced a new task in which subjects were instructed to perform both depth and rivalry tasks concurrently. Subjects were clearly able to perform both tasks at the same time, but with a modest, symmetric drop in performance when compared to either task carried out alone. Subjects were also able to raise performance levels for either task by performing it with a higher priority, with a decline in performance for the other task. The symmetric declines in performance are consistent with the interpretation that the two tasks are equally demanding of attention (Braun and Julesz 1998, Perception & Psychophysics 60 1–23). The results demonstrate the impressive combination of binocular features that supports coincident depth and rivalry in surface perception, within the constraints of presumed orientation and spatial frequency channels.
With or without a Hole: Young Infants' Sensitivity for Topological versus Geometric Property
Authors: Chien Sarina Hui-Lin , Lin Yun-Lan , Qian Wenli , Zhou Ke , Lin Ming-Kuan , Hsu Hsin-Yueh
Published: May 2012

Evidence from adult psychophysics, brain imaging, and honeybee's behaviour has been reported to support the notion that topological properties are the primitives of visual representation (Chen, 1982 Science218 699–700). Here, we ask how the sensitivity to topological property might originate during development. Specifically, we tested 1.5- to 6-month-old infants' visual sensitivity for topological versus geometric properties with the forced-choice novelty preference technique. A disk and a ring were used in the topologically different condition (experiment 1), while a disk and a triangle were used in the geometrically different condition (experiment 2). Spontaneous preferences for the disk, the ring, and the triangle were measured pairwise using the preferential looking-time technique (experiment 3). The results showed that infants could reliably discriminate stimuli based on topological differences, but failed to do so with geometric differences. Moreover, in the generalisation task, infants showed higher novelty preference for the topologically different figure (the ring). In addition, the results of both experiments cannot be attributed to a spontaneous preference for the ring or for the disk. Further analysis on individual infants' age and performance revealed two distinct developmental trends. Infants seem to be sensitive to topological differences as young as 1.5 months, while their ability to discriminate geometric differences was at chance before 3 months and gradually improved with age. Taken together, our findings suggested an early sensitivity for topological property, at least for the detection of stimuli with or without a hole.
Effects of backgrounding and finishing growth rates on P8 fat and intramuscular fat in Bos taurus steers
Authors: McPhee M. J. , Harden S. , Robinson D. L. , Dicker R. W. , Oddy V. H.
Published: May 2012

The present study investigates the effects of backgrounding and finishing growth rates of Bos taurus steers grown out on three post-weaning growth pathways, across 4 years (1995–1998) on fat deposition. Scanned P8 fat at backgrounding exit (SP8exit), scanned P8 fat before slaughter (SP8sla) and carcass intramuscular fat (IMF, %) were evaluated. Four equations to predict SP8sla and four equations to predict carcass IMF across years were developed. Three post-weaning growth pathways (GPs) generated by different nutritional treatments across years were used in the study. Growth pathways were created by backgrounding steers on pasture with no supplementation (GP1), pasture plus supplementary feeding formulated pellets (GP2) or pasture with access to a forage crop (GP3). The steers were then finished in a feedlot or on pasture to slaughter weights of 520 kg (Korean market specification) or 600 kg (Japanese market specification). Cubic smoothing splines were fitted to the liveweight of all animals from the start of backgrounding until slaughter. Backgrounding growth rates were interpolated off the GP curves and the mean average daily gain (ADG, kg/day) at Day 100 (D100, Days 100–91 before relocation to the finishing phase), and Day 150 (D150, Days 150–141 before relocation to the finishing phase) were calculated. Significant (P < 0.01) differences between SP8exit and backgrounding ADG (BADG) were detected in all years except GP2 v. GP3 in 1997. GP1 steers had the lowest BADG across all years, ranging from 0.39 to 0.88 kg/day. At backgrounding exit, the mean SP8exit for the different GPs was ranked, with GP1 < GP3 for all years, with significant (P < 0.01) differences among GP1, GP2 and GP3 in all years except 1996. At the end of finishing, the mean carcass IMF over all years and finish (pasture and feedlot) (P < 0.05) was 4.71% for GP1 v. 5.09% for GP3 for Korean market steers and the mean SP8sla (P < 0.01) was 14.59 mm for GP1 v. 16.04 mm for GP3 and the mean carcass IMF (P < 0.01) was 5.54% for GP1 v. 6.27% for GP3 for Japanese market steers. The residual correlation of the multivariate response variables, namely, D100, D150 and BADG v. SP8exit (n = 1054), SP8sla (n = 1049) and carcass IMF (n = 1002), indicated that the highest correlations, all significant (P < 0.01), were 0.33, 0.20 and 0.12 for BADG v. SP8exit, SP8sla and carcass IMF, respectively. The residual variances (mm2) of the four SP8sla equations were 6.14, 7.44, 8.72 and 10.73 for 1995, 1996, 1997 and 1998, respectively, and the residual variances (%2) for the four carcass IMF equations were 2.51, 2.26, 1.75 and 0.84, for 1995, 1996, 1997 and 1998, respectively.
Growth and carcass characteristics of crossbred lambs in various production systems
Authors: Fogarty N. M. , Mulholland J. G.
Published: May 2012

Lamb growth, carcass and pelt measurements are reported from 5775 lambs born to Border Leicester × Merino (BLM) and Hyfer (Dorset × Merino composite) ewes joined to Dorset, Suffolk and Hyfer rams in three lamb-production systems at Cowra and Wagga Wagga over 5 years. The production systems involved lambings at different seasons of the year and increasing levels of intensification from autumn annual joining, spring joining with a backup mating for non-pregnant ewes, to an accelerated 8-monthly lambing system. Lambs from BLM ewes were 0.7 kg heavier at birth and grew 3% faster and reached slaughter, at 18 kg carcass weight, 1–2 weeks earlier than did lambs from Hyfer ewes (P < 0.01). The advantage in growth rate of lambs from BLM compared with Hyfer ewes was greater for lambs born in November. These lambs had poorer growing conditions over the summer months, with 22% lower growth rate and taking 5 weeks longer to reach slaughter than did lambs born in March or August. There was no difference between Dorset and Suffolk sire breeds for any lamb growth traits, with lambs from Hyfer sires growing 7% slower. Ram and cryptorchid lambs reached slaughter 1 week earlier than did wethers, with ewes a further 9 days later (P < 0.01). Sex differences were maximised when lamb growth was greatest. There were no differences in carcass fat measurements between ram and cryptorchid lambs, although both were considerably leaner than wethers (2.2–3.0 mm fat at the GR site), which were 1.3–2.1 mm leaner than ewes at 18-kg carcass weight. The range in average growth rate of progeny of the BLM ewes from the 12 different source flocks at Cowra and Wagga Wagga was 10–14% of the mean which was twice the difference in average growth rate of progeny from the BLM and Hyfer dams. There was also significant variation among the BLM source flocks for carcass fat measurements. Lamb progeny from the different sire- and dam-breed combinations had varying levels of heterozygosity. There appears to be little loss of heterosis or hybrid vigour for lamb growth, although the sire breed × dam breed interaction was significant (P < 0.01) for age at slaughter at Wagga Wagga, in which the ranking of the lamb types was consistent with the levels of heterozygosity. The estimates of between-lambing repeatability for the ewes were highest for birthweight (0.35 Cowra and 0.27 Wagga Wagga) and declined at later ages (0.26–0.17), with lower estimates for carcass traits.
Choline-releasing glycerophosphodiesterase EDI3 drives tumor cell migration and metastasis
Authors: Stewart Joanna D. , Marchan Rosemarie , Lesjak Michaela S. , Lambert Joerg , Hergenroeder Roland , Ellis James K. , Lau Chung-Ho , Keun Hector C. , Schmitz Gerd , Schiller Juergen , Eibisch Mandy , Hedberg Christian , Waldmann Herbert , Lausch Ekkehart , Tanner Berno , Sehouli Jalid , Sagemueller Jens , Staude Hagen , Steiner Eric , Hengstler Jan G.
Published: May 2012

Metastasis from primary tumors remains a major problem for tumor therapy. In the search for markers of metastasis and more effective therapies, the tumor metabolome is relevant because of its importance to the malignant phenotype and metastatic capacity of tumor cells. Altered choline metabolism is a hallmark of cancer. More specifically, a decreased glycerophosphocholine (GPC) to phosphocholine (PC) ratio was reported in breast, ovarian, and prostate cancers. Improved strategies to exploit this altered choline metabolism are therefore required. However, the critical enzyme cleaving GPC to produce choline, the initial step in the pathway controlling the GPC/PC ratio, remained unknown. In the present work, we have identified the enzyme, here named EDI3 (endometrial differential 3). Purified recombinant EDI3 protein cleaves GPC to form glycerol-3-phosphate and choline. Silencing EDI3 in MCF-7 cells decreased this enzymatic activity, increased the intracellular GPC/PC ratio, and decreased downstream lipid metabolites. Downregulating EDI3 activity inhibited cell migration via disruption of the PKCα signaling pathway, with stable overexpression of EDI3 showing the opposite effect. EDI3 was originally identified in our screening study comparing mRNA levels in metastasizing and nonmetastasizing endometrial carcinomas. Both Kaplan–Meier and multivariate analyses revealed a negative association between high EDI3 expression and relapse-free survival time in both endometrial (
P
< 0.001) and ovarian (
P
= 0.029) cancers. Overall, we have identified EDI3, a key enzyme controlling GPC and choline metabolism. Because inhibition of EDI3 activity corrects the GPC/PC ratio and decreases the migration capacity of tumor cells, it represents a possible target for therapeutic intervention.
Position sensitivity in the visual word form area
Authors: Rauschecker Andreas M. , Bowen Reno F. , Parvizi Josef , Wandell Brian A.
Published: May 2012

Seeing words involves the activity of neural circuitry within a small region in human ventral temporal cortex known as the visual word form area (VWFA). It is widely asserted that VWFA responses, which are essential for skilled reading, do not depend on the visual field position of the writing (position invariant). Such position invariance supports the hypothesis that the VWFA analyzes word forms at an abstract level, far removed from specific stimulus features. Using functional MRI pattern-classification techniques, we show that position information is encoded in the spatial pattern of VWFA responses. A right-hemisphere homolog (rVWFA) shows similarly position-sensitive responses. Furthermore, electrophysiological recordings in the human brain show position-sensitive VWFA response latencies. These findings show that position-sensitive information is present in the neural circuitry that conveys visual word form information to language areas. The presence of position sensitivity in the VWFA has implications for how word forms might be learned and stored within the reading circuitry.
The chromatin remodeling complex NuRD establishes the poised state of rRNA genes characterized by bivalent histone modifications and altered nucleosome positions
Authors: Xie Wenbing , Ling Te , Zhou Yonggang , Feng Weijun , Zhu Qiaoyun , Stunnenberg Henk G. , Grummt Ingrid , Tao Wei
Published: May 2012

rRNA genes (rDNA) exist in two distinct epigenetic states, active promoters being unmethylated and marked by euchromatic histone modifications, whereas silent ones are methylated and exhibit heterochromatic features. Here we show that the nucleosome remodeling and deacetylation (NuRD) complex establishes a specific chromatin structure at rRNA genes that are poised for transcription activation. The promoter of poised rRNA genes is unmethylated, associated with components of the preinitiation complex, marked by bivalent histone modifications and covered by a nucleosome in the “off” position, which is refractory to transcription initiation. Repression of rDNA transcription in growth-arrested and differentiated cells correlates with elevated association of NuRD and increased levels of poised rRNA genes. Reactivation of transcription requires resetting the promoter-bound nucleosome into the “on” position by the DNA-dependent ATPase CSB (Cockayne syndrome protein B). The results uncover a unique mechanism by which ATP-dependent chromatin remodeling complexes with opposing activities establish a specific chromatin state and regulate transcription.
Hydrogen sulfide and nitric oxide are mutually dependent in the regulation of angiogenesis and endothelium-dependent vasorelaxation
Authors: Coletta Ciro , Papapetropoulos Andreas , Erdelyi Katalin , Olah Gabor , Módis Katalin , Panopoulos Panagiotis , Asimakopoulou Antonia , Gerö Domokos , Sharina Iraida , Martin Emil , Szabo Csaba
Published: May 2012

Hydrogen sulfide (H
2
S) is a unique gasotransmitter, with regulatory roles in the cardiovascular, nervous, and immune systems. Some of the vascular actions of H
2
S (stimulation of angiogenesis, relaxation of vascular smooth muscle) resemble those of nitric oxide (NO). Although it was generally assumed that H
2
S and NO exert their effects via separate pathways, the results of the current study show that H
2
S and NO are mutually required to elicit angiogenesis and vasodilatation. Exposure of endothelial cells to H
2
S increases intracellular cyclic guanosine 5′-monophosphate (cGMP) in a NO-dependent manner, and activated protein kinase G (PKG) and its downstream effector, the vasodilator-stimulated phosphoprotein (
VASP
). Inhibition of endothelial isoform of NO synthase (eNOS) or PKG-I abolishes the H
2
S-stimulated angiogenic response, and attenuated H
2
S-stimulated vasorelaxation, demonstrating the requirement of NO in vascular H
2
S signaling. Conversely, silencing of the H
2
S-producing enzyme cystathionine-γ-lyase abolishes NO-stimulated cGMP accumulation and angiogenesis and attenuates the acetylcholine-induced vasorelaxation, indicating a partial requirement of H
2
S in the vascular activity of NO. The actions of H
2
S and NO converge at cGMP; though H
2
S does not directly activate soluble guanylyl cyclase, it maintains a tonic inhibitory effect on PDE5, thereby delaying the degradation of cGMP. H
2
S also activates PI3K/Akt, and increases eNOS phosphorylation at its activating site S1177. The cooperative action of the two gasotransmitters on increasing and maintaining intracellular cGMP is essential for PKG activation and angiogenesis and vasorelaxation. H
2
S-induced wound healing and microvessel growth in matrigel plugs is suppressed by pharmacological inhibition or genetic ablation of eNOS. Thus, NO and H
2
S are mutually required for the physiological control of vascular function.
Evaluation of Nature‐Like and Technical Fishways for the Passage of Alewives at Two Coastal Streams in New England
Authors: Franklin Abigail E. , Haro Alex , Castro‐Santos Theodore , Noreika John
Published: May 2012

Nature‐like fishways have been designed with the intent to reconnect river corridors and provide passage for all species occurring in a system. The approach is gaining popularity both in Europe and North America, but performance of these designs has not been quantitatively evaluated in a field setting for any North American species. Two nature‐like fishways and three technical fishways in New England were evaluated for passage of anadromous adult alewivesAlosa pseudoharengusby using passive integrated transponder (PIT) telemetry. A perturbation boulder rock ramp (32 m long; 4.2% slope) constructed in Town Brook (Plymouth, Massachusetts) passed 94% of the fish that made passage attempts, with most fish ascending the ramp in less than 22 min. In the East River (Guilford, Connecticut), a step‐pool bypass design (48 m long; 7.1% slope) passed only 40% of attempting fish, with a median transit time of 75 min. In Town Brook, a technical pool‐and‐weir fishway (14 m long; 14.3% slope) exhibited poor entry and poor passage for the fish. In contrast, in the East River, two technical steeppass fishways (3 m long; 29.6% and 9.6% slopes) passed the majority of available fish, although one of these steeppass fishways may have lacked sufficient flow to attract fish to the entrance. In both Town Brook and the East River, tagged fish passed rapidly downstream through all fishways after spawning. In the East River, the amount of time fish spent in the spawning habitat before migrating downstream ranged from 1 to 41 d. These studies demonstrate that some nature‐like and technical fishway designs can effectively facilitate passage of alewives, but a fishway's location in relation to a spillway is important, and further evaluations are required to more precisely identify the influence of the vertical drop per pool and the specific local hydraulics on alewife behaviors and passage performance.
Rational or reckless? Georgia's zugzwang in the Caucasus
Authors: Siroky David S. , Dzutsev Valeriy
Published: May 2012

Although the 2008 Russian-Georgian war was a military defeat for Georgia, it has only reinforced Georgia's westward trajectory. One noteworthy difference from Georgia's pre-war policy is a new regional strategy — the North Caucasus Initiative — that seeks to create a soft power alternative to Russia's military dominance in the region. We suggest that this approach is rational rather than reckless, as some critics have claimed. It represents a carefully calculated strategy that is already benefiting Georgia and from which all concerned parties, including Russia, stand to gain. If the South and North Caucasus were more open and less divided — a direction in which this new initiative appears to point — the Caucasus could become more prosperous and more stable. That would serve Russia's long-term interest by significantly reducing the cost of subsidies to sustain and stabilize the volatile region.
Price discovery by the market's mind: an investor's perspective on numerical archetypes
Authors: Schotanus Patrick
Published: May 2012

The aim of this paper is to contribute to Jung's later work, with a particular focus on the numerical archetypes viewed from an investor's perspective. It attempts to achieve this via a three-pronged approach. First, placing complex psychology in the framework of complexity theory allows a robust acknowledgement and treatment of ‘elusive’ macroscopic properties, i.e. archetypal dynamics, involved in the ordering of a mind as a complex adaptive system. Second, modern insights in number sense (the direct intuition of what numbers mean) provide neuroscientific support for numerical archetypes and clarify their primacy. Third, this paper points to the empirical relevance of numerical archetypes in price discovery, the self-organizing principle of the capital markets (which allocate resources in modern society). The resulting proposition is that the (collective) mind's unconscious and conscious forces can be considered as ‘intelligent’ agents. The competition between these two domains provides the necessary condition to endogenously generate innovative outcomes, the essential capability of complex adaptive systems. According to this view producing such adaptive novelty is achieved in the form of intuitive insights and imagination, which result in a vast array of symbols, e.g. prices in the case of the market's mind.
Anomalous optical properties of GaMnAs/AlAs quantum wells grown by molecular beam epitaxy
Authors: Rodrigues D H , Brasil M J S P , Gobato Y Galvão , Holgado D P A , Marques G E , Henini M
Published: May 2012

We have investigated the optical properties of GaMnAs/AlAs quantum wells (QWs) grown by molecular beam epitaxy under relatively high substrate temperatures (400 and 450 °C) and low Mn concentrations (⩽0.1%). We have studied the time- and polarized-resolved photoluminescence emission as a function of the laser power and an applied magnetic field. Several anomalous results have been observed including long decay times, enhancement of the diamagnetic shift and reduction in the polarization degree with increasing Mn concentration.
Effects of temperature, loading rate and nanowire length on torsional deformation and mechanical properties of aluminium nanowires investigated using molecular dynamics simulation
Authors: Sung Po-Hsien , Wu Cheng-Da , Fang Te-Hua
Published: May 2012

Single-crystal aluminium nanowires under torsion are studied using molecular dynamics simulations based on the many-body tight-binding potential. The effects of temperature, loading rate and nanowire length are evaluated in terms of atomic trajectories, potential energy, von Mises stress, a centrosymmetry parameter, torque, shear modulus and radial distribution function. Simulation results clearly show that torsional deformation begins at the surface, extends close to the two ends and finally diffuses to the middle part. The critical torsional angle which represents the beginning of plastic deformation varies with different conditions. Before the critical torsional angle is reached, the potential energy and the torque required for the deformation of a nanowire significantly increase with the torsional angle. The critical torsional angle increases with increasing nanowire length and loading rate and decreasing temperature. The torque required for the deformation decreases and the shear modulus increases with increasing nanowire length. For higher temperatures and higher loading rates, torsional buckling more easily occurs at the two ends of a nanowire, whereas it occurs towards the middle part at or below room temperature with lower loading rates. Geometry instability occurs before material instability (buckling) for a long nanowire.
Stepped piezoresistive microcantilever designs for biosensors
Authors: Ansari Mohd Zahid , Cho Chongdu , Urban Gerald
Published: May 2012

The sensitivity of a piezoresistive microcantilever biosensor strongly depends on its ability to convert the surface stress-induced deflections into large resistance change. To improve the sensitivity, we present stepped microcantilever biosensor designs that show significant resistance change compared with commonly used rectangular designs. The cantilever is made of silicon dioxide with a u-shaped silicon piezoresistor. The surface stress-induced deflections, bimorph deflection, fundamental resonant frequency and self-heating properties of the cantilever are studied using the FEM software. The surface stress-induced deflections are compared against the analytical model derived in this work. Results show that stepped designs have better signal-to-noise ratio than the rectangular ones and cantilevers with l/L between 0.5 and 0.75 are better designs for improving sensitivity.
Reciprocity in long pulse duration laser interactions with polymers
Authors: Marchant A L , Snelling H V
Published: May 2012

The laser irradiation of polyimide Kapton HN (PI), polyetheretherketone (PEEK), polyethyleneterephthalate (PET) and polypropylene (PP) by long pulse, radio frequency excited, CO2 laser radiation has been studied. In the pulse duration range 47–757 µs the minimum pulse energy required to damage the surface is found to be independent of exposure time. Hence, the threshold fluence is also independent of pulse duration; the same effect is achieved through the application of long pulses at low irradiance as shorter ones at higher irradiance. The values of these threshold fluences have been found to be 8.15 J cm−2, 5.36 J cm−2, 3.39 J cm−2 and 9.63 J cm−2 for PI, PEEK, PET and PP, respectively. The details of this behaviour have been analysed through calculations of the laser-induced temperature rise and the application of an Eyring-type rate law for the thermal decomposition of polyimide and PEEK and by considering the melting points of PP and PET.
On gas flow effects in 3D edge transport simulations for DIII-D plasmas with resonant magnetic perturbations
Authors: Frerichs H. , Reiter D. , Schmitz O. , Harting D. , Evans T.E. , Feng Y.
Published: May 2012

Pumping of neutral gas and re-fuelling in other locations (e.g. neutral beam injection or gas puffing) are key ingredients in divertor physics. However, these have not been included in previous 3D edge plasma transport simulations with the EMC3–EIRENE code. Including these effects brings the simulations closer to reality and we demonstrate that this has a significant impact on divertor parameters. In particular, we study the impact of the pumping efficiency on ITER similar shape plasmas at the DIII-D tokamak in the presence of resonant magnetic perturbations. Further, we investigate the so-called ‘particle pump-out effect’. We show that in the present transport model and for given pumping and re-fuelling rates, the density at the transition to the core region decreases with increasing perturbation current and also the temperature. The striation patterns in the target particle and heat fluxes are extended into the regular scrape-off layer, which is caused by cross-field transport into a thin layer around the perturbed separatrix.