bluuebunny/crossref_metadata_2025 huggingface dataset:
Volcanic signals in oceans
Authors: Stenchikov Georgiy , Delworth Thomas L. , Ramaswamy V. , Stouffer Ronald J. , Wittenberg Andrew , Zeng Fanrong
Published: August 2009

Sulfate aerosols resulting from strong volcanic explosions last for 2–3 years in the lower stratosphere. Therefore it was traditionally believed that volcanic impacts produce mainly short‐term, transient climate perturbations. However, the ocean integrates volcanic radiative cooling and responds over a wide range of time scales. The associated processes, especially ocean heat uptake, play a key role in ongoing climate change. However, they are not well constrained by observations, and attempts to simulate them in current climate models used for climate predictions yield a range of uncertainty. Volcanic impacts on the ocean provide an independent means of assessing these processes. This study focuses on quantification of the seasonal to multidecadal time scale response of the ocean to explosive volcanism. It employs the coupled climate model CM2.1, developed recently at the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory, to simulate the response to the 1991 Pinatubo and the 1815 Tambora eruptions, which were the largest in the 20th and 19th centuries, respectively. The simulated climate perturbations compare well with available observations for the Pinatubo period. The stronger Tambora forcing produces responses with higher signal‐to‐noise ratio. Volcanic cooling tends to strengthen the Atlantic meridional overturning circulation. Sea ice extent appears to be sensitive to volcanic forcing, especially during the warm season. Because of the extremely long relaxation time of ocean subsurface temperature and sea level, the perturbations caused by the Tambora eruption could have lasted well into the 20th century.
How sediment promotes narrow rifting: Application to the Gulf of California
Authors: Bialas Robert W. , Buck W. Roger
Published: August 2009

If the gravitational stress changes related to crustal thinning are large enough to affect the mode of extension, then sedimentation should also affect that mode. We propose that the weight of sediments reduces the difference in crustal buoyancy forces caused by local crustal thinning, allowing a rift to extend more easily in a narrow rift mode. We examine the effect of deposition of large amounts of nonlocally derived sediment on extensional style using two‐dimensional, regional‐scale numerical experiments of extending thick continental crust with varied initial thermal conditions, geometries, rheological parameters, and sedimentation properties. Depending on initial model conditions, the onset of rifting in thick continental crust occurs in the narrow rifting, wide rifting, or core complex mode. With continued extension, all cases eventually transition to a narrow rifting mode. For a system in wide rift mode, moderate to fast sedimentation shortens the time needed to transition to a narrow rift. In the Gulf of California, changes in extensional style correlate with sediment thickness, with an earlier transition to narrow rifting in the north versus the south. We compare our model results to the extensional history of the Gulf of California, where sediments may have caused the northern and north central domain of the gulf (Delfin‐Tiburon and Guaymas segments) to transition to narrow rifting before the south central domains (Alarcon segment).
Impact of modeled versus satellite measured tropical precipitation on regional smoke optical thickness in an aerosol transport model
Authors: Xian Peng , Reid Jeffrey S. , Turk Joseph F. , Hyer Edward J. , Westphal Douglas L.
Published: August 2009

Aerosol and climate models are dependent on the parameterizations of the underlying meteorological model. Precipitation schemes in global meteorological models are designed to close the regional water budget, without concern for representative wet removal. By substituting numerical model precipitation for a multi‐satellite precipitation dataset, we demonstrate the impact of modeled versus satellite‐derived precipitation on aerosol optical depth (AOD) in the Navy Aerosol Analysis and Prediction System (NAAPS). The model and satellite‐derived precipitation are shown to have similar precipitation amounts, but the precipitation area from the model is about twice that in the satellite data. The resulting difference in scavenging results in an increase in mid‐visible AOD of about 20–200% in parts of Southeast Asia and South America during the burning seasons (or 0.1–0.2 in AOD). This suggests that care must be taken when combining free‐running model and remote sensing data to evaluate smoke‐cloud interactions or to estimate source magnitudes.
Declining annual streamflow distributions in the Pacific Northwest United States, 1948–2006
Authors: Luce C. H. , Holden Z. A.
Published: August 2009

Much of the discussion on climate change and water in the western United States centers on decreased snowpack and earlier spring runoff. Although increasing variability in annual flows has been noted, the nature of those changes is largely unexplored. We tested for trends in the distribution of annual runoff using quantile regression at 43 gages in the Pacific Northwest. Seventy‐two percent of the stations showed significant (α = 0.10) declines in the 25th percentile annual flow, with half of the stations exceeding a 29% decline and a maximum decline of 47% between 1948 and 2006. Fewer stations showed statistically significant declines in either median or mean annual flow, and only five had a significant change in the 75th percentile, demonstrating that increases in variance result primarily from a trend of increasing dryness in dry years. The asymmetric trends in streamflow distributions have implications for water management and ecology well beyond those of shifted timing alone, affect both rain and snow‐dominated watersheds, and contribute to earlier timing trends in high‐elevation watersheds.
Impact of organized intraseasonal convective perturbations on the tropical circulation
Authors: Bellenger Hugo , Duvel Jean‐Philippe , Lengaigne Matthieu , Levan Phu
Published: August 2009

Using an atmospheric Global Circulation Model (GCM), we study the dynamical response of the tropical atmosphere to large‐scale convective perturbations. We hypothesize that such perturbations can be triggered by intraseasonal SST anomalies. We thus compare two ensembles of simulations forced either with actual daily SST fields (high frequency, HF) or with low‐pass filtered SST fields (T > 90 days; low frequency, LF). In HF simulations, there is a small increase of seasonal mean precipitation, but a strong and statistically significant increase of the low‐level westerly flow. It is argued that it is mostly the “aggregation” of the convection into a few large‐scale organized intraseasonal events, and not the intensification of the seasonal mean precipitation, that acts to intensify the low‐level westerly flow in the HF simulations. This non‐linear behavior shows that a correct representation of intraseasonal variability is required for a correct simulation of the average tropical circulation.
A model for the relationship between tropical precipitation and column water vapor
Authors: Muller Caroline J. , Back Larissa E. , O'Gorman Paul A. , Emanuel Kerry A.
Published: August 2009

Several observational studies have shown a tight relationship between tropical precipitation and column‐integrated water vapor. We show that the observed relationship in the tropics between column‐integrated water vapor, precipitation, and its variance can be qualitatively reproduced by a simple and physically motivated two‐layer model. It has previously been argued that features of this relationship could be explained by analogy with the theory of continuous phase transitions. Instead, our model explicitly assumes that the onset of precipitation is governed by a stability threshold involving boundary‐layer water vapor. This allows us to explain the precipitation‐humidity relationship over a broader range of water vapor values, and may explain the observed temperature dependence of the relationship.
Coastal conduit in southwestern Hudson Bay (Canada) in summer: Rapid transit of freshwater and significant loss of colored dissolved organic matter
Authors: Granskog Mats A. , Macdonald Robie W. , Kuzyk Zou Zou A. , Senneville Simon , Mundy Christopher‐John , Barber David G. , Stern Gary A. , Saucier Francois
Published: August 2009

Distributions of freshwater (sea‐ice melt and runoff) were investigated along inshore‐offshore sections in southwestern Hudson Bay for fall conditions. Conductivity‐temperature‐density profiles and bottle samples collected for salinity, oxygen isotope (δ18O), and colored dissolved organic matter (CDOM) analyses were used to discriminate between contributions of river water (RW) and sea‐ice melt (SIM). Stations had a fresh summer surface mixed layer 5–25 m thick overlying a cold subsurface layer indicative of the previous winter's polar mixed layer (PML). The fraction of RW decreased strongly with distance from shore, while the opposite was true for SIM. The majority of RW was constrained in a coastal domain within 100–150 km from shore, which, because of high alongshore velocities, accounts for the majority of freshwater and volume transports. On the basis of freshwater inventories and composition, brine and RW accumulate in the PML over winter because of ice formation and downward mixing. The summer surface circulation results in an annual net export of SIM from the region. Residence times for freshwater components in the southwestern sector of the bay, based on currents derived from a 3‐D ocean model for Hudson Bay, are about 1–10 months, implying rapid transit of freshwater. Despite the short residence time for RW (1–3 months), CDOM is significantly photobleached and provides an unreliable tracer for RW. Photobleaching represents an important sink for dissolved organic carbon entering from rivers and could, in part, explain why Hudson Bay is only a minor sink for atmospheric CO2 in the open water season.
Dynamics of wind‐forced coherent anticyclones in the open ocean
Authors: Koszalka Inga , Bracco Annalisa , McWilliams James C. , Provenzale Antonello
Published: August 2009

We numerically study the dynamics of coherent anticyclonic eddies in the ocean interior. For the hydrostatic, rotating, stably stratified turbulence we use a high‐resolution primitive equation model forced by small‐scale winds in an idealized configuration. Many properties of the horizontal motions are found to be similar to those of two‐dimensional and quasi‐geostrophic turbulence. Major differences are a strong cyclone‐anticyclone asymmetry linked to the straining field exerted by vortex Rossby waves, which is also found in shallow water flows, and the complex structure of the vertical velocity field, which we analyze in detail. Locally, the motion can become strongly ageostrophic, and vertical velocities associated with vortices can reach magnitudes and levels of spatial complexity akin to those reported for frontal regions. Transport and mixing properties of the flow field are further investigated by analyzing Lagrangian trajectories. Particles released in the pycnocline undergo large vertical excursions because of the vertical velocities associated to the vortices, with potentially important consequences for marine ecosystem dynamics.
Simulation of birdfoot delta formation with application to the Mississippi Delta
Authors: Seybold H. J. , Molnar P. , Singer H. M. , Andrade J. S. , Herrmann H. J. , Kinzelbach W.
Published: August 2009

Recently, Seybold et al. (2007) proposed a reduced complexity model which simulates the process of delta formation on geological time scales. It includes subaerial and subaqueous growth in a three‐dimensional framework. In this paper we apply this model to the formation of a river‐dominated delta and compare the model dynamics with observations of the formation of the Balize Lobe of the Mississippi River Delta. The model generates both subaerial and subaqueous channels and lateral levee formations as well as a profile morphology with steep drop‐offs and a flat delta surface which is similar to natural ones. We show that the dimensionless parameters of the model may be consistently rescaled to match the Balize Lobe. This means that after rescaling the water flows, the subaerial geometry and time, the deposited (subaqueous) lobe volume, the sediment and water flows, the age, as well as the sediment capture ratio match the observed data. Finally, we use detrended fluctuation analysis to show that the modeled long‐term dynamics of the delta formation process shows a complex temporal correlation structure. A characteristic time scale separates periods of consistent delta growth by gradual sediment deposition at the mouths of distributary channels from periods during which random large‐scale channel avulsions lead to rapid change and the formation of new channels and subaqueous‐dominated deposition.
Photochemical degradation of dissolved organic matter and dissolved lignin phenols from the Congo River
Authors: Spencer Robert G. M. , Stubbins Aron , Hernes Peter J. , Baker Andy , Mopper Kenneth , Aufdenkampe Anthony K. , Dyda Rachael Y. , Mwamba Vincent L. , Mangangu Arthur M. , Wabakanghanzi Jose N. , Six Johan
Published: August 2009

Photochemical degradation of Congo River dissolved organic matter (DOM) was investigated to examine the fate of terrigenous DOM derived from tropical ecosystems. Tropical riverine DOM receives greater exposure to solar radiation, particularly in large river plumes discharging directly into the open ocean. Initial Congo River DOM exhibited dissolved organic carbon (DOC) concentration and compositional characteristics typical of organic rich blackwater systems. During a 57 day irradiation experiment, Congo River DOM was shown to be highly photoreactive with a decrease in DOC, chromophoric DOM (CDOM), lignin phenol concentrations (Σ8) and carbon‐normalized yields (Λ8), equivalent to losses of ∼45, 85–95, >95 and >95% of initial values, respectively, and a +3.1 ‰ enrichment of the δ13C‐DOC signature. The loss of Λ8 and enrichment of δ13C‐DOC during irradiation was strongly correlated (r = 0.99, p < 0.01) indicating tight coupling between these biomarkers. Furthermore, the loss of CDOM absorbance was correlated to the loss of Λ8 (e.g., a355 versus Λ8; r = 0.98, p < 0.01) and δ13C‐DOC (e.g., a355 versus δ13C; r = 0.97, p < 0.01), highlighting the potential of CDOM absorbance measurements for delineating the photochemical degradation of lignin and thus terrigenous DOM. It is apparent that these commonly used measurements for examination of terrigenous DOM in the oceans have a higher rate of photochemical decay than the bulk DOC pool. Further process‐based studies are required to determine the selective removal rates of these biomarkers for advancement of our understanding of the fate of this material in the ocean.
The joys and perils of recombination - The hotspot conversion paradox and the evolution of recombination
Authors: Pineda-Krch Mario , Redfield Rosemary
Published: August 2009

The contradiction between the long-term persistence of the chromosomal hotspots that initiate meiotic recombination and the self-destructive mechanism by which they act strongly suggests that our understanding of recombination is incomplete. To investigate the requirements for hotspot persistence, Rosemary Redfield and I developed a computer simulation model, hotspot, of their activity and its evolutionary consequences.
Competition between spiders and pitcher plants? Prey availability and trophic interactions in bogs
Authors: Hart Clarisse , Mejia Jonathan , Gotelli Nicholas , Ellison Aaron
Published: August 2009

Web-building spiders (e.g. Frontinella communis and Neriene radiata) and northern pitcher plants (Sarracenia purpurea) are co-occurring sit-and-wait predators that may compete for shared arthropod prey. We evaluated prey availability and capture rates by web-weaving spiders and pitcher plants in a headwater stream box complex (Harvard Pond) in central Massachusetts. We established 40 plots with spider and pitcher plant removal treatments, and collected arthropod prey captured by open pitcher plants, pitfall traps, and sticky traps in those plots. The removal of web-building spiders significantly changed the distribution of prey captured by the pitcher plants (Chi-square test: P = 2.2 × 10-16 at Harvard Pond). Plugging pitcher plants yielded no difference in prey capture by sticky traps or pitfall traps. In pitcher plants, the total number of Odonata, Diptera, and Hemiptera captured more than doubled when web-weaving spiders were removed from the plots. In pitfall traps in web-weaving spider removal plots, the total number of ants decreased by more than 50%. Hunting spider capture by sticky traps showed moderate increase (P = 0.08) when web-weaving spiders were removed, suggesting an unforeseen interaction between these groups of spiders. The increased predation risk of hunting spiders on ants may explain the marked decrease in ant activity when web-weaving spiders were removed.
Decadal-scale changes in seagrass coverage on the Mississippi barrier islands, northern Gulf of Mexico
Authors: Carter Gregory , Criss G. Alan , Blossom Gabriel , Biber Patrick
Published: August 2009

Seagrasses provide habitat for a wide variety of aquatic species, and reduce coastal erosion via sediment stabilization. The areal coverage of seagrass beds on the Mississippi barrier islands appears to have declined substantially since the 1960s. However, difficulties in sampling benthic vegetation, differences among previous studies in survey methods, and a lack of data on year-to-year variation in coverage have impeded quantitative study of this decline. Thus, the goal of the present study was to utilize historical remote sensing data to quantitatively determine changes in seagrass (predominantly Halodule wrightii Ascherson) coverage on the Mississippi barrier islands. Analyses were limited to imagery acquired during late summer through autumn, when seagrass canopies remained fully developed and water turbidity was low. Given these conditions, seagrass beds were readily identifiable in older black-and-white to color aerial photographs as well as in more recent multi-spectral imagery.On Horn, the largest Mississippi island, seagrass coverage declined from 77 ha in 1940 to 19 ha in 1971. Coverage had returned to its 1940 value by 2006, but declined again in 2007. Seagrass coverage on Petit Bois, the most rapidly-migrating island, declined from 54 ha in 1940 to an approximately stable 8-19 ha from 1952 through 2007. Petit Bois was the only island for which decline in seagrass coverage corresponded with decline in island land area. On the smallest island, East Ship, seagrass coverage remained nearly constant at 16-19 ha from 1963-2007 despite dramatic reductions in land area during Hurricanes Camille (1969) and Katrina (2005). On West Ship, coverage dropped to zero in 2003 but increased by 2007 to slightly exceed its 1975 value of 18 ha. Data for Cat Island extended only from 2003-2007. Seagrass coverage more than tripled during this period, from 22 ha in 2003 to 71 ha in 2007. Protection from trawling may have been a significant factor in the post-1995 recovery of seagrass on Horn Island. The absence of a similar recovery on Petit Bois may be linked with its rapid westward migration in combination with a nearly 40% reduction in land area from 1940-2007. There was no discernable negative impact of Hurricane Camille or Hurricane Katrina on seagrass coverage. Methodological differences (e.g., mapping potential seagrass habitat rather than existing seagrass beds) are important in explaining the dramatic decline in seagrass coverage that is apparent when recent data are compared with results of earlier surveys.
Fluorine substitutions in an antigenic peptide selectively modulate T-cell receptor binding in a minimally perturbing manner
Authors: Piepenbrink Kurt H. , Borbulevych Oleg Y. , Sommese Ruth F. , Clemens John , Armstrong Kathryn M. , Desmond Clare , Do Priscilla , Baker Brian M.
Published: August 2009

TCR (T-cell receptor) recognition of antigenic peptides bound and presented by MHC (major histocompatibility complex) molecules forms the basis of the cellular immune response to pathogens and cancer. TCRs bind peptide–MHC complexes weakly and with fast kinetics, features which have hindered detailed biophysical studies of these interactions. Modified peptides resulting in enhanced TCR binding could help overcome these challenges. Furthermore, there is considerable interest in using modified peptides with enhanced TCR binding as the basis for clinical vaccines. In the present study, we examined how fluorine substitutions in an antigenic peptide can selectively impact TCR recognition. Using a structure-guided design approach, we found that fluorination of the Tax peptide [HTLV (human T-cell lymphotropic virus)-1 Tax11-19] enhanced binding by the Tax-specific TCR A6, yet weakened binding by the Tax-specific TCR B7. The changes in affinity were consistent with crystallographic structures and fluorine chemistry, and with the A6 TCR independent of other substitutions in the interface. Peptide fluorination thus provides a means to selectively modulate TCR binding affinity without significantly perturbing peptide composition or structure. Lastly, we probed the mechanism of fluorine's effect on TCR binding and we conclude that our results were most consistent with a ‘polar hydrophobicity’ mechanism, rather than a purely hydrophobic- or electrostatic-based mechanism. This finding should have an impact on other attempts to alter molecular recognition with fluorine.
Reduction in renal ACE2 expression in subtotal nephrectomy in rats is ameliorated with ACE inhibition
Authors: Velkoska Elena , Dean Rachael G. , Burchill Luke , Levidiotis Vicki , Burrell Louise M.
Published: August 2009

Alterations within the RAS (renin–angiotensin system) are pivotal for the development of renal disease. ACE2 (angiotensin-converting enzyme 2) is expressed in the kidney and converts the vasoconstrictor AngII (angiotensin II) into Ang-(1–7), a peptide with vasodilatory and anti-fibrotic actions. Although the expression of ACE2 in the diabetic kidney has been well studied, little is known about its expression in non-diabetic renal disease. In the present study, we assessed ACE2 in rats with acute kidney injury induced by STNx (subtotal nephrectomy). STNx and Control rats received vehicle or ramipril (1 mg·kg−1 of body weight·day−1), and renal ACE, ACE2 and mas receptor gene and protein expression were measured 10 days later. STNx rats were characterized by polyuria, proteinuria, hypertension and elevated plasma ACE2 activity (all P<0.01) and plasma Ang-(1–7) (P<0.05) compared with Control rats. There was increased cortical ACE binding and medullary mas receptor expression (P<0.05), but reduced cortical and medullary ACE2 activity in the remnant kidney (P<0.05 and P<0.001 respectively) compared with Control rats. In STNx rats, ramipril reduced blood pressure (P<0.01), polyuria (P<0.05) and plasma ACE2 (P<0.01), increased plasma Ang-(1–7) (P<0.001), and inhibited renal ACE (P<0.001). Ramipril increased both cortical and medullary ACE2 activity (P<0.01), but reduced medullary mas receptor expression (P<0.05). In conclusion, our results show that ACE2 activity is reduced in kidney injury and that ACE inhibition produced beneficial effects in association with increased renal ACE2 activity. As ACE2 both degrades AngII and generates the vasodilator Ang-(1–7), a decrease in renal ACE2 activity, as observed in the present study, has the potential to contribute to the progression of kidney disease.
Measurement of Speech Effort During Fluency-Inducing Conditions in Adults Who Do and Do Not Stutter
Authors: Ingham Roger J. , Bothe Anne K. , Jang Erin , Yates Lauren , Cotton John , Seybold Irene
Published: August 2009

Purpose

To investigate the effects of 4 fluency-inducing (FI) conditions on self-rated speech effort and other variables in adults who stutter and in normally fluent controls.

Method

Twelve adults with persistent stuttering and 12 adults who had never stuttered each completed 4 ABA-format experiments. During A phases, participants read aloud normally. During each B phase, they read aloud in 1 of 4 FI conditions: auditory masking, chorus reading, whispering, and rhythmic speech. Dependent variables included self-judged speech effort and observer-judged stuttering frequency, speech rate, and speech naturalness.

Results

For the persons who stuttered, FI conditions reduced stuttering and speech effort, but only for chorus reading were these improvements obtained without diminishing speech naturalness or speaking rate. By contrast, speech effort increased during all FI conditions for adults who did not stutter.

Conclusions

Self-rated speech effort differentiated the effects of 4 FI conditions on speech performance for adults who stuttered, with chorus reading best approximating normally fluent speech. More generally, self-ratings of speech effort appeared to constitute an independent, reliable, and validly interpretable dimension of fluency that may be useful in the measurement and treatment of stuttering.
A Preliminary Evaluation of Fast ForWord-Language as an Adjuvant Treatment in Language Intervention
Authors: Fey Marc E. , Finestack Lizbeth H. , Gajewski Byron J. , Popescu Mihai , Lewine Jeffrey D.
Published: August 2009

Purpose

Fast ForWord-Language (FFW-L) is designed to enhance children’s processing of auditory–verbal signals and, thus, their ability to learn language. As a preliminary evaluation of this claim, we examined the effects of a 5-week course of FFW-L as an adjuvant treatment with a subsequent 5-week conventional narrative-based language intervention (NBLI) that targeted narrative comprehension and production and grammatical output.

Method

Twenty-three children 6–8 years of age with language impairments were assigned randomly to 1 of 3 intervention sequences: (a) FFW-L/NBLI, (b) NBLI/FFW-L, or (c) wait/NBLI. We predicted that after both treatment periods, the FFW-L/NBLI group would show greater gains on measures of narrative ability, conversational grammar, and nonword repetition than the other groups.

Results

After the first 5-week study period, the intervention groups, taken together (i.e., FFW-L/NBLI and NBLI/FFW-L), significantly outperformed the no-treatment wait/NBLI group on 2 narrative measures. At the final test period, all 3 groups displayed significant time-related effects on measures of narrative ability, but there were no statistically significant between-groups effects of intervention sequence.

Conclusions

This preliminary study provides no evidence to support the claim that FFW-L enhances children’s response to a conventional language intervention.
Evidence for Adverse Phonatory Change Following an Inhaled Combination Treatment
Authors: Erickson Elizabeth , Sivasankar Mahalakshmi
Published: August 2009

Purpose

Voice problems are reported as a frequent side effect of inhaled combination (IC) treatments. The purpose of this experimental study was to investigate whether IC treatments are detrimental to phonation. We hypothesized that IC treatment would significantly increase phonation threshold pressure (PTP) and perceived phonatory effort (PPE), whereas sham treatment would not.

Method

Fourteen healthy adults participated in a repeated-measures design in which they received IC and sham treatments in counterbalanced order. PTP and PPE were measured prior to treatments, immediately following treatments, and at 1 and 2 hr following treatments.

Results

IC treatment increased PTP, but sham treatment did not. The increase in PTP was maintained for a 2 hr period following administration. PPE ratings were not significantly correlated with PTP.

Conclusions

IC treatments can have acute, adverse effects on phonation. Detrimental phonatory effects were elicited in participants with no self-reported voice problems. IC treatments are being increasingly prescribed across the lifespan. The current data increase our understanding of the nature of phonatory deterioration associated with IC treatment and lay the groundwork for increased research effort to develop IC treatments that effectively control respiratory disease while minimizing an adverse effect on phonation.
Do Left and Right Matter for Haptic Recognition of Familiar Objects?
Authors: Craddock Matt , Lawson Rebecca
Published: August 2009

Two experiments were carried out to examine the effects of dominant right versus non-dominant left exploration hand and left versus right object orientation on haptic recognition of familiar objects. In experiment 1, participants named 48 familiar objects in two blocks. There was no dominant-hand advantage to naming objects haptically and there was no interaction between exploration hand and object orientation. Furthermore, priming of naming was not reduced by changes of either object orientation or exploration hand. To test whether these results were attributable to a failure to encode object orientation and exploration hand, experiment 2 replicated experiment 1 except that the unexpected task in the second block was to decide whether either exploration hand or object orientation had changed relative to the initial naming block. Performance on both tasks was above chance, demonstrating that this information had been encoded into long-term haptic representations following the initial block of naming. Thus when identifying familiar objects, the haptic processing system can achieve object constancy efficiently across hand changes and object-orientation changes, although this information is often stored even when it is task-irrelevant.
Enhanced developmental potential of heat-shocked porcine parthenogenetic embryos is related to accelerated mitogen-activated protein kinase dephosphorylation
Authors: Isom S. Clay , Prather Randall S. , Rucker III Edmund B.
Published: August 2009

Recently, we demonstrated that a 9-h heat shock of 42°C can have marked stimulatory effects on porcine parthenogenetic embryo development if applied immediately after oocyte activation. Developmental discrepancies between heat-shocked (HS) and non-HS embryos were manifest as early as 3 h after activation, suggesting involvement of maturation promoting factor (MPF) and/or mitogen-activated protein kinase (MAPK). Analysis of cdc2 kinase activity showed that MPF inactivation occurred at similar rates in HS and control embryos upon oocyte activation. However, MAPK dephosphorylation was accelerated in HS embryos compared with controls. Okadaic acid, a protein phosphatase inhibitor, maintained MAPK activity at high levels in both non-HS and HS embryos and sensitised HS embryos to the effects of elevated temperatures. No increase in heat shock proteins was observed in pronuclear-stage HS embryos. These data suggest that the acceleration of development observed in HS porcine parthenogenetic embryos is associated with a precocious inactivation of the MAPK signalling cascade. The faster cleavage divisions observed in HS embryos may be linked physiologically to their enhanced developmental potential in vitro.
Metabolic labeling and direct imaging of choline phospholipids in vivo
Authors: Jao Cindy Y. , Roth Mary , Welti Ruth , Salic Adrian
Published: August 2009

Choline (Cho)-containing phospholipids are the most abundant phospholipids in cellular membranes and play fundamental structural as well as regulatory roles in cell metabolism and signaling. Although much is known about the biochemistry and metabolism of Cho phospholipids, their cell biology has remained obscure, due to the lack of methods for their direct microscopic visualization in cells. We developed a simple and robust method to label Cho phospholipids in vivo, based on the metabolic incorporation of the Cho analog propargylcholine (propargyl-Cho) into phospholipids. The resulting propargyl-labeled phospholipid molecules can be visualized with high sensitivity and spatial resolution in cells via a Cu(I)-catalyzed cycloaddition reaction between the terminal alkyne group of propargyl-Cho and a labeled azide. Total lipid analysis of labeled cells shows strong incorporation of propargyl-Cho into all classes of Cho phospholipids; furthermore, the fatty acid composition of propargyl-Cho-labeled phospholipids is very similar to that of normal Cho phospholipids. We demonstrate the use of propargyl-Cho in cultured cells, by imaging phospholipid synthesis, turnover, and subcellular localization by both fluorescence and electron microscopy. Finally, we use propargyl-Cho to assay microscopically phospholipid synthesis in vivo in mouse tissues.
Book Reviews
Authors: Hermann Kirstine Lintrup
Published: August 2009

Teaching Atlas of Urologic Imaging. First edition. By R. A. Older & M. J. Bassignani. Stuttgart, New York: Thieme Medical Publishers, 2009. ISBN: 978-1-60406-016-4. 330 pages, 390 illustrations. Price (hardback): EUR 119.95
Book review
Authors: Cwikiel Wojciech
Published: August 2009

Vascular Imaging. By K. J. Wolf, Z. Grozdanowic, T. Albrecht, J. Heidenreich, A. Shilling, & F. Wacker. Stuttgart/New York: Georg Thieme, 2009. ISBN: 978-3-13-145181-1. 295 pages, 250 illustrations. Price (paperback): USD 59.95, EUR 44.95
Passive Control of Attachment in Legged Space Robots
Authors: Gasparetto Alessandro , Vidoni Renato , Seidl Tobias
Published: August 2009

In the space environment the absence of gravity calls for constant safe attachment of any loose object, but the low‐pressure conditions prohibit the use of glue‐type adhesives. The attachment system of freely hunting spiders, e.g. Evarcha arcuata, employs van der Waals forces and mechanical interlocking. Furthermore, detachment is achieved passively and requires little force. Hence, the spider serves as a model for a versatile legged robot for space applications, e.g. on the outer surface of a space station. In this paper, we analyse the dry attachment systems of E. arcuata and geckos as well as the kinematics of freely hunting spiders. We generalise the results of biological studies on spider locomotion and mobility, including the major movement and the position constraints set by the dry adhesion system. From these results, we define a simplified spider model and study the overall kinematics of the legs both in flight and in contact with the surface. The kinematic model, the data on spider gait characteristics and the adhesion constraints are implemented in a kinematic simulator. The simulator results confirm the principal functionality of our concept.
A Novel Uni‐Acupoint Electroacupuncture Stimulation Method for Pain Relief
Authors: Niu Chuansen , Hao Hongwei , Lu Jun , Li Luming , Han Zhirong , Tu Ya
Published: August 2009

Electroacupuncture stimulation (EAS) has been demonstrated effective for pain relief and treating other various diseases. However, the conventional way of EAS, the bi‐acupoint method, is not suitable for basis study of acupoint specificity. Moreover, its operations are inconvenient and difficult to be persevered, especially for long‐term, continuous and even imperative treatments. These disadvantages motivate designs of new EAS methods. We present a novel uni‐acupoint electrical stimulation method, which is applied at a single acupoint and quite meets the needs of basis study and simpler clinical application. Its pain relief effect has been evaluated by animal tests of Wistar rats. During the experiments, rats were given 30 min 2/100 Hz uni‐ and bi‐acupoint EAS and their nociceptive thresholds before and after EAS were attained by hot‐plate test. The analgesic effect was defined as the change of nociceptive threshold and used to evaluate the effectiveness of uni‐acupoint EAS for pain relief. The hot‐plate test results indicated that analgesic effect of uni‐acupoint group was significantly higher than that of the control group and there was no significant difference of analgesic effects between uni‐ and bi‐acupoint EAS. The results suggested that uni‐acupoint method was an effective EAS method and had comparable pain relief effect with bi‐acupoint method.
Full‐Length Sequence of Mouse Acupuncture‐Induced 1‐L (Aig1l) Gene Including Its Transcriptional Start Site
Authors: Ohta Mika , Sugano Aki , Goto Shuji , Yusoff Surini , Hirota Yushi , Funakoshi Kotaro , Miura Kenji , Maeda Eiichi , Takaoka Nobuo , Sato Nobuko , Ishizuka Hiroshi , Arizono Naoki , Nishio Hisahide , Takaoka Yutaka
Published: August 2009

We have been investigating the molecular efficacy of electroacupuncture (EA), which is one type of acupuncture therapy. In our previous molecular biological study of acupuncture, we found an EA‐induced gene, named acupuncture‐induced 1‐L (Aig1l), in mouse skeletal muscle. The aims of this study consisted of identification of the full‐length cDNA sequence of Aig1l including the transcriptional start site, determination of the tissue distribution of Aig1l and analysis of the effect of EA on Aig1l gene expression. We determined the complete cDNA sequence including the transcriptional start site via cDNA cloning with the cap site hunting method. We then analyzed the tissue distribution of Aig1l by means of northern blot analysis and real‐time quantitative polymerase chain reaction. We used the semiquantitative reverse transcriptase‐polymerase chain reaction to examine the effect of EA on Aig1l gene expression. Our results showed that the complete cDNA sequence of Aig1l was 6073 bp long, and the putative protein consisted of 962 amino acids. All seven tissues that we analyzed expressed the Aig1l gene. In skeletal muscle, EA induced expression of the Aig1l gene, with high expression observed after 3 hours of EA. Our findings thus suggest that the Aig1l gene may play a key role in the molecular mechanisms of EA efficacy.
Mutagenic Activity of Indigofera truxillensis and I. suffruticosa Aerial Parts
Authors: Calvo Tamara Regina , Cardoso Cássia Regina Primila , da Silva Moura Adriana Candido , dos Santos Lourdes Campaner , Colus Ilce Mara Syllos , Vilegas Wagner , Varanda Eliana Aparecida
Published: August 2009

Indigofera truxillensis and I. suffruticosa, are used as a source of indigo dye and to treat several diseases. The mutagenic activity of the methanolic extracts from aerial parts, glycerolipid, flavonoid and alkaloid fractions of the extract were evaluated by means of Salmonella/microsome assays using TA100, TA98, TA102 and TA97a strains. The methanolic extract of I. truxillensis showed mutagenic activity in the TA98 strain without S9 while glycerolipid fraction was devoid of activity. The flavonoid and alkaloid fractions of both plants showed mutagenicity. Chemical analysis of flavonoid fractions of I. truxillensis and I. suffruticosa resulted in the identification of kaempferol, quercetin and their derivatives. The alkaloid fraction of both the species contained indigo and indirubin and indigo was found mainly responsible for the mutagenic activity.
Ave festiva ferculisand Josquin's Spanish Reputation
Authors: Kreitner Kenneth
Published: August 2009

Tarazona 2/3, a cathedral manuscript preserving mostly the music of Peñalosa and his Spanish contemporaries, contains one motet, with the text ‘Ave festiva ferculis’, attributed to ‘Jusquin’. It is a strange piece of music, clearly not the work of Josquin des Prez, but also very unusual within the manuscript, and its misattribution suggests that Josquin's actual music was not a familiar icon in Spainc.1530. This impression is supported by the sources, which reveal a real Spanish Josquin craze beginning in the 1540s, but a much spottier picture, emphasizing the early sacred music, in the decades before. Josquin's strong influence on Spanish music came late.
Virtual Opera, or Opera between the Ears
Authors: Nicholls David
Published: August 2009

A number of authors, including John Covach and especially Edward Macan, have investigated the links between art music and progressive rock. This article builds on and extends such work by positing, defining, discussing and dissecting a hybrid genre I term virtual opera. Exemplified by such albums as The Who's Tommy (1969) and Quadrophenia (1973), Genesis's The Lamb Lies Down on Broadway (1974) and Frank Zappa's Joe's Garage (1979), each of which is subjected to detailed examination, virtual operas find their ideal site of performance between the ears of individual listeners, rather than on stage or screen. In each case, the aural and visual dimensions of the albums combine to create multi-layered musico-dramatic narratives, freed from the usual performance constraints associated with either opera or rock.
Cold Storage of Human Milk: Effect on Its Bacterial Composition
Authors: Marín María L , Arroyo Rebeca , Jiménez Esther , Gómez Adolfo , Fernández Leonides , Rodríguez Juan M
Published: August 2009

Objectives:

In the last few years, it has been proved that human milk contains bacteria that constitute an important factor in the initiation and development of the neonatal gut microbiota. In this context, the objective of this study was to evaluate the effect of cold storage on the natural bacterial composition of breast milk.

Materials and Methods:

Breast milk samples provided by 34 healthy women and collected either by manual expression (n = 27) or breast pump (n = 7), were plated onto several culture media immediately after arrival at the laboratory (day 0) and after storage at −20°C for 6 weeks. A high number of isolates from 8 of the women were identified at the species level.

Results:

No statistically significant differences were observed between the counts obtained at both sampling times in those media in which growth was detected. In all of the culture media, bacterial counts in pump‐collected samples were higher than in those obtained by manual expression. Staphylococci and streptococci were the predominant bacteria in both fresh and frozen samples, Staphylococcus epidermidis being the most abundant species at both sampling times. Lactic acid bacteria and bifidobacteria were also present in fresh and frozen breast milk samples, but among them, only 1 species (Lactobacillus gasseri) could be isolated at both sampling times.

Conclusions:

The results of this study suggest that cold storage of milk at −20°C for 6 weeks does not significantly affect either the quantitative or the qualitative bacterial composition of breast milk.
Diagnosing Pediatric Functional Abdominal Pain in Children (4–15 Years Old) According to the Rome III Criteria: Results From a Norwegian Prospective Study
Authors: Helgeland Helene , Flagstad Gro , Grøtta Jon , Vandvik Per Olav , Kristensen Hanne , Markestad Trond
Published: August 2009

Objectives:

To determine the proportion of referred children with nonorganic abdominal pain who meet the criteria for 1 or more diagnoses of functional gastrointestinal disorders (FGID), explore the distribution of diagnoses according to the revised pediatric Rome III criteria (PRC‐III), and to investigate reasons for failure to meet these criteria.

Materials and Methods:

We recruited children (4–15 years) consecutively referred by general practitioners to 4 general pediatric outpatient clinics for the evaluation of recurrent abdominal pain. FGID diagnoses were based on the Questionnaire on Pediatric Gastrointestinal Symptoms–Rome III version, completed by parents. To exclude organic disease, all patients underwent medical investigations and were reevaluated at follow‐up after 6 to 9 months.

Results:

Of the 152 patients included, 142 (93%) had functional abdominal pain. Of these, 124 (87%) met the criteria for 1 or more diagnoses according to the PRC‐III: 66% met the criteria for 1, 29% for 2, and 5% for 3 diagnoses. Irritable bowel syndrome was the most common diagnosis (43%) and overlapped with aerophagia in 16 children (38% of the children with overlapping diagnoses) and with abdominal migraine in 14 (33%). In the 18 patients (13%) not fulfilling the PRC‐III for any FGID diagnosis, the main reason was insufficient pain frequency (83%).

Conclusions:

Of the referred children with functional abdominal pain, 87% met the PRC‐III for specific diagnoses. This supports the use of these criteria as a diagnostic tool. The significant overlap between different FGIDs, however, makes it unclear whether some of the diagnoses represent distinct disorders or artificial categories.
Prevalence and Clinical Relevance of cagA, vacA, and iceA Genotypes of Helicobacter pylori Isolated From Slovenian Children
Authors: Homan Matjaž , Luzar Boštjan , Kocjan Boštjan J , Orel Rok , Močilnik Tina , Shrestha Maja , Kveder Maja , Poljak Mario
Published: August 2009

Background:

Although infection with Helicobacter pylori in children mostly induces asymptomatic chronic gastritis, the clinical outcome of H pylori infection is generally unpredictable. To identify the risk subgroup of infected children who can progress toward serious gastrointestinal disease, we assessed the prevalence of H pylori virulence genes cagA, vacA, and iceA in children from southeastern Europe and correlated their presence with the severity of histological changes in the stomach.

Materials and Methods:

A total of 165 children (age range 4–18 years, mean 13 years) with H pylori infection were studied for a 6‐year period. Virulence genes were determined by polymerase chain reaction from biopsy samples.

Results:

The cagA gene was present in 61.2% of patients. The predominant vacA genotype was s1m1 (42%), followed by s1m2 (28%), and s2m2 (24%). IceA genotypes iceA1 and iceA2 were detected in 62% and 31% of the samples, respectively. Multiple genotypes were found in 11.5% of isolates. The H pylori density score, the degree of chronic and acute inflammation, correlated with a cagA‐positive status (P < 0.01, P < 0.01, P = 0.01, respectively). Higher bacterial infiltration (P < 0.01) and degree of chronic inflammation (P = 0.03) were detected in vacA s1–positive samples.

Conclusion:

CagA, vacA s1m1, and iceA1 genotypes are the predominant genotypes of H pylori isolated from the southeastern European pediatric population. CagA and vacA s1 are important virulence determinants of H pylori in children, but were not found associated with an increased incidence of precancerous gastric lesions.
Italian Paediatricians' Approach to Coeliac Disease Diagnosis
Authors: Auricchio Renata , Granata Viviana , Borrelli Melissa , Troncone Riccardo ,   Italian Society for Pediatric Gastroenterology Hepatology and Nutrition (SIGENP)
Published: August 2009

The aim of this study was to investigate the current implementation of the 1990 ESPGHAN criteria for the diagnosis of celiac disease (CD) in Italy to form a foundation for their revision.

From September 2006 to March 2007 a nationwide questionnaire concerning current diagnostic methods was sent by mail to 54 Italian centres for the diagnosis of CD, which were distributed across the entire national territory. The questionnaire investigated the tests performed, diagnostic criteria currently used, and the management of some special cases in each centre.

Eighty percent of the centres use anti‐tissue transglutaminase to diagnose CD and anti‐endomysium antibodies to confirm the results. Fifty‐five percent still use anti‐gliadin antibodies. A total of 87.5% of centres perform HLA typing, especially in first‐degree relatives and in unclear diagnosis. Regarding histology, 67.5% of centres consider an infiltrative lesion consistent with diagnosis of CD. The majority of centres (85%) use the 1990 ESPGHAN criteria for both symptomatic and asymptomatic patients, but 80% do not perform a second biopsy in asymptomatic cases or a gluten challenge in children younger than 2 years of age. Furthermore, most centres (72.5%) do not prescribe a gluten‐free diet to asymptomatic patients with positive serology and normal bowel architecture (ie, potential cases), but they do program a careful follow‐up.

In conclusion, ESPGHAN criteria are widely followed by Italian CD centres. However, their revision may be useful, but it should be evidence based. Large, multicentre studies are greatly needed.