bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil organic carbon sequestration potential of cropland in China
Authors: Qin Zhangcai , Huang Yao , Zhuang Qianlai
Published: July 2013

Soil organic carbon (SOC) in cropland is of great importance to the global carbon (C) balance and to agricultural productivity, but it is highly sensitive to human activities such as irrigation and crop rotation. It has been observed that under certain improved management practices, cropland soils can sequestrate additional C beyond their existing SOC level before reaching the C saturation state. Here we use data from worldwide, long‐term agricultural experiments to develop two statistical models to determine the saturated SOC level (SOCS) in upland and paddy agroecosystems, respectively. We then use the models to estimate SOC sequestration potential (SOCP) in Chinese croplands. SOCP is the difference between SOCS and existing SOC level (SOCE). We find that the models for both the upland and paddy agroecosystems can reproduce the observed SOCS data from long‐term experiments. The SOCE and SOCS stock in Chinese upland and paddy croplands (0–30 cm soil) are estimated to be 5.2 and 7.9 Pg C with national average densities of 37.4 and 56.8 Mg C ha−1, respectively. As a result, the total SOC sequestration potential is estimated to be 2.7 Pg C or 19.4 Mg C ha−1 in Chinese cropland. Paddy has a relatively higher SOCE (45.4 Mg C ha−1) than upland (34.7 Mg C ha−1) and also a greater SOCP at 26.1 Mg C ha−1 compared with 17.2 Mg C ha−1 in the upland. The SOC varies dramatically among different regions. Northeast China has the highest SOCE and SOCS density, while the Loess Plateau has the greatest SOCP density. The time required to reach SOC saturation in Chinese cropland is highly dependent on management practices applied. Chinese cropland has relatively low SOC density in comparison to the global average but could have great potentials for C sequestration under improved agricultural management strategies.
BMI1, The polycomb‐group gene, is recurrently targeted by genomic rearrangements in progressive B‐cell leukemia/lymphoma
Authors: Rouhigharabaei Leila , Ferreiro Julio Finalet , Put Natalie , Michaux Lucienne , Tousseyn Thomas , Lefebvre Christine , Gardiner Anne , De Kelver Wim , Demuynck Hilde , Verschuere Johan , Théate Ivan , Vicente Carmen , Vandenberghe Peter , Cools Jan , Wlodarska Iwona
Published: July 2013

BMI1, a Polycomb‐group gene located at 10p12.2, is implicated in the pathogenesis of a variety of tumors. However, the genetic molecular mechanisms underlying its aberrant expression in cancer cells remain largely unknown. In this study, we show that BMI1 is recurrently targeted by chromosomal aberrations in B‐cell leukemia/lymphoma. We identified a novel t(10;14)(p12;q32)/IGH‐BMI1 rearrangement and its IGL variant in six cases of chronic lymphocytic leukemia (CLL) and found that these aberrations were consistently acquired at time of disease progression and high grade transformation of leukemia (Richter syndrome). The IG‐BMI1 translocations were not associated with any particular molecular subtype of CLL and the leukemias were negative for common mutations of NOTCH1 and TP53, known to increase a risk of progression and transformation in CLL. In addition, using FISH and SNP array analysis, we identified a wide range of BMI1‐involving 10p12 lesions in 17 cases of mantle cell lymphoma (MCL). These aberrations included various balanced and unbalanced structural abnormalities and very frequently but not exclusively, were associated with gain of the BMI1 locus and loss of the 10p terminal sequences. These findings point to genomic instability at the 10p region in MCL which likely promotes rearrangements and deregulation of BMI1. Our findings are in line with previously published observations correlating overexpression of BMI1 with tumor progression and chemoresistance. In summary, our study provides new insights into genetic molecular mechanisms underlying aberrant expression of BMI1 in lymphoma and documents its contribution in the pathogenesis of Richter syndrome and MCL. © 2013 Wiley Periodicals, Inc.
A Kernel Regression Approach to Gene‐Gene Interaction Detection for Case‐Control Studies
Authors: Larson Nicholas B. , Schaid Daniel J.
Published: July 2013

Gene‐gene interactions are increasingly being addressed as a potentially important contributor to the variability of complex traits. Consequently, attentions have moved beyond single locus analysis of association to more complex genetic models. Although several single‐marker approaches toward interaction analysis have been developed, such methods suffer from very high testing dimensionality and do not take advantage of existing information, notably the definition of genes as functional units. Here, we propose a comprehensive family of gene‐level score tests for identifying genetic elements of disease risk, in particular pairwise gene‐gene interactions. Using kernel machine methods, we devise score‐based variance component tests under a generalized linear mixed model framework. We conducted simulations based upon coalescent genetic models to evaluate the performance of our approach under a variety of disease models. These simulations indicate that our methods are generally higher powered than alternative gene‐level approaches and at worst competitive with exhaustive SNP‐level (where SNP is single‐nucleotide polymorphism) analyses. Furthermore, we observe that simulated epistatic effects resulted in significant marginal testing results for the involved genes regardless of whether or not true main effects were present. We detail the benefits of our methods and discuss potential genome‐wide analysis strategies for gene‐gene interaction analysis in a case‐control study design.
Chemical weathering on the North Island of New Zealand: CO2 consumption and fluxes of Sr and Os
Authors: Blazina Tim , Sharma Mukul
Published: July 2013

We present Os and Sr isotope ratios and Os, Sr and major/trace element concentrations for river waters, spring waters and rains on the North Island of New Zealand. The Os and Sr data are used to examine whether the NINZ is a significant contributor of unradiogenic Os and Sr to the oceans. Major element chemistry is used to quantify weathering and CO2 consumption rates on the island to investigate relationships between these processes and Os and Sr behavior. Chemical erosion rates and CO2 consumption rates across the island range from 44 to 555 km−2 yr−1 and 95 to 1900 × 103 mol CO2 km−2 yr−1, respectively. Strontium flux for the island range from 177 to 16,100 mol km−2 yr−1 and the rivers have an average flux normalized 87Sr/86Sr ratio of 0.7075. In agreement with the previous studies these findings provide further evidence that weathering of arc terrains contributes a disproportionally large amount of Sr to the oceans and consumes very large amounts of CO2 annually compared to their areal extent. However, the 87Sr/86Sr from the NINZ is not particularly unradiogenic and it is likely not contributing significant amounts of unradiogenic Sr to the oceans. Repeated Os analyses and bottle leaching experiments revealed extensive and variable sample contamination by Os leaching from rigorously precleaned LDPE bottles. An upper bound on the flux of Os from NINZ can nevertheless be assessed and indicates that island arcs cannot provide significant amounts of unradiogenic Os to the oceans.
Age, distance, and geochemical evolution within a monogenetic volcanic field: Analyzing patterns in the Auckland Volcanic Field eruption sequence
Authors: Le Corvec Nicolas , Bebbington Mark S. , Lindsay Jan M. , McGee Lucy E.
Published: July 2013

The Auckland Volcanic Field (AVF) is a young active monogenetic basaltic field, which contains ∼50 volcanoes scattered across the Auckland metropolitan area. Understanding the temporal, spatial, and chemical evolution of the AVF during the last c.a. 250 ka is crucial in order to forecast a future eruption. Recent studies have provided new age constraints and potential temporal sequences of the past eruptions within the AVF. We use this information to study how the spatial distribution of the volcanic centers evolves with time, and how the chemical composition of the erupted magmas evolves with time and space. We seek to develop a methodology which compares successive eruptions to describe the link between geochemical and spatiotemporal evolution of volcanic centers within a monogenetic volcanic field. This methodology is tested with the present day data of the AVF. The Poisson nearest neighbor analysis shows that the spatial behavior of the field has been constant overtime, with the spatial distribution of the volcanic centers fitting the Poisson model within the significance levels. The results of the meta‐analysis show the existence of correlations between the chemical composition of the erupted magmas and distance, volume, and time. The apparent randomness of the spatiotemporal evolution of the volcanic centers observed at the surface is probably influenced by the activity of the source. The methodology developed in this study can be used to identify possible relationships between composition trends and volume, time and/or distance to the behavior of the source, for successive eruptions of the AVF.
Chorus functional dependencies derived from CRRES data
Authors: Spasojevic M. , Shprits Y. Y.
Published: July 2013

Using data from the Combined Release and Radiation Effects Satellite (CRRES) plasma wave experiment, we present quadratic fits to the mean of the wave amplitude squared, , for lower and upper band chorus as a function of geomagnetic activity (Kp) and magnetic latitude (λ) for the midnight (21<MLT≤3), dawn (3<MLT≤9), and postnoon (12<MLT≤15) sectors and present an ad hoc model for the prenoon (9<MLT≤12) sector. The empirical models are valid for 4≤L≤7, |λ|<15° and Kp≤6 and quantify the dramatic difference in the latitudinal dependence of chorus as a function of local time and how that dependence varies with geomagnetic condition, critical parameters for calculating wave‐induced electron scattering rates. Our results are generally consistent with previous studies, and our key contribution is the quantification of wave properties in a manner that is easily incorporated into global quasi‐linear diffusion models.
Characterization and scaling of mesoscale heterogeneities in sandstones
Authors: Pini Ronny , Benson Sally M.
Published: July 2013

A core‐flooding technique to measure core‐ and subcore‐scale capillary pressure curves is applied to the characterization of a naturally heterogeneous sandstone core. N2 and water are used as the nonwetting and wetting fluid phases, and X‐ray imaging is applied to precisely visualize multiphase flow at the subcentimeter scale. The spatial variability in the Pc(S) relationship is represented in terms of scaling factors, which are further translated into a corresponding distribution of permeabilities, thus creating a unique and consistent framework where multiphase and rock properties are integrated. The analysis introduced here provides a practical and efficient method for characterizing subcore‐scale heterogeneities, whose effects can be substantial on both single and multiphase flows.
An agent‐based model of dune interactions produces the emergence of patterns in deserts
Authors: Génois Mathieu , du Pont Sylvain Courrech , Hersen Pascal , Grégoire Guillaume
Published: July 2013

Crescent‐shaped barchan dunes are highly mobile dunes which are ubiquitous on Earth and other solar system bodies. Although they are unstable when considered separately, they form large assemblies in deserts and spatially organize in narrow corridors that extend in the wind direction. Collision of barchans has been proposed as a mechanism to redistribute sand between dunes and prevent the formation of very large dunes. Here we use an agent‐based model with elementary rules of sand redistribution during collisions to access the full dynamics of very large barchan fields. We tune the dune field density by changing the sand load/lost ratio and follow the transition between dilute fields, where barchans barely interact, and dense fields, where dune collisions control and stabilize the dune field. In this dense regime, barchans have a small, well‐selected size and form flocks: the dune field self‐organizes in narrow corridors of dunes, as it is observed in real dense barchan deserts.
Land subsidence at aquaculture facilities in the Yellow River delta, China
Authors: Higgins Stephanie , Overeem Irina , Tanaka Akiko , Syvitski James P. M.
Published: July 2013

Differential Interferometric Synthetic Aperture Radar is applied to the coast of the Yellow River delta (YRD) in China. Like many deltas, the coastline of the YRD is dominated by aquaculture. Advanced Land Observation Satellite Phased Array L‐Band Synthetic Aperture Radar (SAR) and Envisat Advanced SAR data acquired between 2007 and 2011 show that subsidence rates are as high as 250 mm/y at aquaculture facilities, likely due to groundwater pumping. These rates exceed local and global average sea level rise by nearly 2 orders of magnitude and suggest that subsidence and associated relative sea level rise may present a significant hazard for Asian megadeltas.
A reduced complexity model for dynamic similarity in obstructed shear flows
Authors: Papke A. , Battiato I.
Published: July 2013

Coupled flows through and over permeable media, also known as obstructed shear flows, are ubiquitous to many environmental systems at different scales, including aquatic flows over sediment beds, and atmospheric flows over crops and cities. Despite their differences, such flows exhibit strong dynamic similarities among systems and scales, as evidenced by the recent finding of empirical universal scaling laws correlating relevant length and velocity scales. We propose a reduced complexity model for obstructed shear channel flows, which couples Brinkman with Reynolds equations to describe the flow within and above the obstruction. We derive scaling laws by intermediate asymptotic analysis of a Darcy‐Brinkman type solution in the low permeability limit. The approach highlights the importance of the effective permeability of the obstruction as a critical parameter governing the system dynamical response. The model results are in good agreement with the scaling laws empirically calculated in other studies.
Crustal evolution across the southern Appalachians: Initial results from the SESAME broadband array
Authors: Parker E. Horry , Hawman Robert B. , Fischer Karen M. , Wagner Lara S.
Published: July 2013

Receiver functions from the EarthScope Southeastern Suture of the Appalachian Margin Experiment broadband deployment and U.S. Transportable Array were analyzed to constrain average crustal thickness and composition across the southern Appalachians. Low Vp/Vs ratios (1.69–1.72) across the Carolina terrane and parts of the Inner Piedmont indicate that the crust has a felsic average composition. The results are consistent with models of thin‐skinned thrusting of Carolina arc fragments over Laurentian basement, whereas arc collision models require significant crustal modification to explain the low Vp/Vs. New crustal thickness estimates provide constraints on the extent of the Blue Ridge crustal root. The present root may be a remnant of a broader structure formed by Alleghanian thrust loading. Root preservation is attributed to Mesozoic heating and thinning of the lower crust beneath outboard terranes, leaving colder Blue Ridge crust largely intact. However, thickened crust (50–55 km) across the region may also be inherited from continental collision during the Proterozoic Grenville orogeny.
The cooling‐rate effect on microwave archeointensity estimates
Authors: Poletti Wilbor , Hartmann Gelvam A. , Hill Mimi J. , Biggin Andrew J. , Trindade Ricardo I. F.
Published: July 2013

New microwave (MW) paleointensity data on historical bricks from Northeast Brazil presented a bias toward higher fields when compared to previous cooling‐rate corrected double‐heating paleointensity estimates; the same relates to the previously reported values for pottery from Southwestern Pacific islands. A simple theoretical approach suggests that the MW bias in both collections is due to a cooling‐rate effect on MW estimates. We then experimentally corrected the MW cooling‐rate effect on Brazilian fragments, increasing the degree of consistency between the previous and new results (reducing discrepancies from 25% to 8%). Results indicate similar experimental behavior between microwave and thermal procedures despite the different ways in which the energy is transferred into the spin system. Finally, they allow cooling times of less than 90 s to be empirically estimated in most of these MW experiments highlighting the need for systematic cooling‐rate corrections to be applied in similar MW paleointensity studies in the future.
Optimization of retinotopy constrained source estimation constrained by prior
Authors: Hagler Donald J.
Published: July 2013

Studying how the timing and amplitude of visual evoked responses (VERs) vary between visual areas is important for understanding visual processing but is complicated by difficulties in reliably estimating VERs in individual visual areas using noninvasive brain measurements. Retinotopy constrained source estimation (RCSE) addresses this challenge by using multiple, retinotopically mapped stimulus locations to simultaneously constrain estimates of VERs in visual areas V1, V2, and V3, taking advantage of the spatial precision of fMRI retinotopy and the temporal resolution of magnetoencephalography (MEG) or electroencephalography (EEG). Nonlinear optimization of dipole locations, guided by a group‐constrained RCSE solution as a prior, improved the robustness of RCSE. This approach facilitated the analysis of differences in timing and amplitude of VERs between V1, V2, and V3, elicited by stimuli with varying luminance contrast in a sample of eight adult humans. The V1 peak response was 37% larger than that of V2 and 74% larger than that of V3, and also ∼10–20 ms earlier. Normalized contrast response functions were nearly identical for the three areas. Results without dipole optimization, or with other nonlinear methods not constrained by prior estimates were similar but suffered from greater between‐subject variability. The increased reliability of estimates offered by this approach may be particularly valuable when using a smaller number of stimulus locations, enabling a greater variety of stimulus and task manipulations.Hum Brain Mapp 35:1815–1833, 2014. © 2013 Wiley Periodicals, Inc.
PATIENT SAFETY IN HOSPITALS – A BAYESIAN ANALYSIS OF UNOBSERVABLE HOSPITAL AND SPECIALTY LEVEL RISK FACTORS
Authors: Zhang Xiaohui , Hauck Katharina , Zhao Xueyan
Published: July 2013

This paper demonstrates how Bayesian hierarchical modelling can be used to evaluate the performance of hospitals. We estimate a three‐level random intercept probit model to attribute unexplained variation in hospital‐acquired complications to hospital effects, hospital‐specialty effects and remaining random variations, controlling for observable patient complexities. The combined information provided by the posterior means and densities for latent hospital and specialty effects can be used to assess the need and scope for improvements in patient safety at different organizational levels. Posterior densities are not conventionally presented in performance assessment but provides valuable additional information to policy makers on what poorly performing hospitals and specialties may be prioritized for policy action. We use surgical patient administrative data for 2005/2006 for 16 specialties in 35 public hospitals in Victoria, Australia. We use posterior means for latent hospital and specialty effects to compare hospital performance in patient safety. Posterior densities and variances are also compared for different specialties to identify clinical areas with greatest scope for improvement. We also show that the same hospital may rank markedly differently for different specialties. Copyright © 2013 John Wiley & Sons, Ltd.
GENDER DIFFERENCES IN ALCOHOL DEMAND: A SYSTEMATIC REVIEW OF THE ROLE OF PRICES AND TAXES
Authors: Nelson Jon P.
Published: July 2013

Gender differences in drinking patterns are potentially important for public policies, especially policies that rely extensively on higher alcohol taxes and prices. This paper presents a systematic review of alcohol prices and gender differences in drinking and heavy drinking by adults and young adults. Starting with a database of 578 studies of alcohol demand and other outcomes, 15 studies are reviewed of adult drinking including discussion of samples, measurement issues, econometric models, special variables, and key empirical results. A similar discussion is presented for eight studies of drinking by young adults, ages 18–26 years. Four conclusions are obtained from the review. First, adult men have less elastic demands compared with women. Second, there is little or no price response by heavy‐drinking adults, regardless of gender. Third, although the sample is small, price might be important for drinking participation by young adults. Fourth, the results strongly suggest that heavy drinking by young adults, regardless of gender, is not easily dissuaded by higher prices. Policy implications, primary study limitations, and suggestions for future research are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
Control of river stage on the reactive chemistry of the hyporheic zone
Authors: Byrne P. , Binley A. , Heathwaite A. L. , Ullah S. , Heppell C. M. , Lansdown K. , Zhang H. , Trimmer M. , Keenan P.
Published: July 2013

We examined the influence of river stage on subsurface hydrology and pore water chemistry within the hyporheic zone of a groundwater‐fed river during the summer baseflow period of 2011. We found river stage and geomorphologic environment to control chemical patterns in the hyporheic zone. At a high river stage, the flux of upwelling water in the shallow sediments (>20 cm) decreased at sample sites in the upper section of our study reach and increased substantially at sites in the lower section. This differential response is attributed to the contrasting geomorphology of these subreaches that affects the rate of the rise and fall of a river stage relative to the subsurface head. At sites where streamward vertical flux decreased, concentration profiles of a conservative environmental tracer suggest surface water infiltration into the riverbed below depths recorded at a low river stage. An increase in vertical flux at sites in the lower subreach is attributed to the movement of lateral subsurface waters originating from the adjacent floodplain. This lateral‐moving water preserved or decreased the vertical extent of the hyporheic mixing zone observed at a low river stage. Downwelling surface water appeared to be responsible for elevated dissolved organic carbon (DOC) and manganese (Mn) concentrations in shallow sediments (0–20 cm); however, lateral subsurface flows were probably important for elevated concentrations of these solutes at deeper levels. Results suggest that DOC delivered to hyporheic sediments during a high river stage from surface water and lateral subsurface sources could enhance heterotrophic microbial activities. Copyright © 2013 John Wiley & Sons, Ltd.
Persistent mechanical allodynia positively correlates with an increase in activated microglia and increased P‐p38 mitogen‐activated protein kinase activation in streptozotocin‐induced diabetic rats
Authors: Cheng K.‐I. , Wang H.‐C. , Chuang Y.‐T. , Chou C.‐W. , Tu H.‐P. , Yu Y.‐C. , Chang L.‐L. , Lai C.‐S.
Published: July 2013

Background

In experimental early painful diabetic neuropathy, persistent hyperglycaemia induces dys‐regulated sodium channel (Navs) expression in the dorsal root ganglion (DRG) and activates microglia in the spinal dorsal horn (SDH). However, information on diabetes‐induced chronic neuropathic pain is limited. Therefore, we investigated abnormal Navs in the DRG and activated glial cells in the SDH of diabetic rats with chronic neuropathic pain.

Methods

Sixty‐six rats were divided into diabetic and control groups: control rats (n = 18; 1 mL of normal saline via the right femoral vein) and diabetic rats [n = 48; 60 mg/kg streptozotocin (STZ) via the right femoral vein]. Hindpaw behavioural tests, Navs expression in the DRG, activation of glial cells in the SDH and the number of neurons in the SDH were measured at 1 and 2 weeks, and 1, 2, 3 and 6 months following saline and STZ administration.

Results

All diabetic rats exhibited hyperglycaemia from day 7 to 6 months. The diabetic rats decreased withdrawal threshold to mechanical stimuli but had blunted responses to thermal stimuli. Consistent up‐regulation of Nav1.3 and down‐regulation of Nav1.8 was observed. Microglial cells were activated early in the SDH and lasted for 6 months. A positive correlation between mechanical allodynia, Nav1.3 and microglial activation was observed. In addition, microglia activation in the SDH of STZ‐induced diabetes was mediated, in part, by phosphorylation of p‐38 mitogen‐activated protein kinase.

Conclusions

Diabetic rats showed hindpaw mechanical allodynia for 6 months. Persistent mechanical allodynia was positively associated with sustained increased activation of Nav1.3 and increased p38 phosphorylation in activated microglia.
Characteristics of older patients with back pain in general practice: BACE cohort study
Authors: Scheele J. , Enthoven W.T.M. , Bierma‐Zeinstra S.M.A. , Peul W.C. , van Tulder M.W. , Bohnen A.M. , Berger M.Y. , Koes B.W. , Luijsterburg P.A.J.
Published: July 2013

Background

Although back pain is common among older people, limited information is available about the characteristics of these patients in primary care. Earlier research suggests that the severity of back symptoms increases with older age.

Methods

Patients aged >55 years visiting a general practitioner with a new episode of back pain were included in the BACE study. Information on patients' characteristics, characteristics of the complaint and physical examination were derived from the baseline measurement. Cross‐sectional differences between patients aged >55–74 and ≥75 years were analysed using an unpaired t‐test, Mann–Whitney U‐test or a chi‐square test.

Results

A total of 675 back pain patients were included in the BACE study, with a median age of 65 (interquartile range 60–71) years. Patients aged >55–74 years had a mean disability score (measured with the Roland Disability Questionnaire) of 9.4 [standard deviation (SD) 5.8] compared with 12.1 (SD 5.5) in patients aged ≥75 years (p ≤ 0.01). The older group reported more additional musculoskeletal disorders and more often had low bone quality (based on ultrasound measurement of the heel) than patients aged >55–74 years. Average back pain severity over the previous week showed no difference (p = 0.11) between the age groups, but severity of back pain at the moment of filling in the questionnaire was higher (p = 0.03) in the older age group.

Conclusions

In this study, older back pain patients reported more disabilities and co‐morbidity. However, the clinical relevance of these differences for the course of the back pain episode in older patients remains a subject for further research.
Coexistence of ipsilateral pain‐inhibitory and facilitatory processes after high‐frequency electrical stimulation
Authors: Vo L. , Drummond P.D.
Published: July 2013

Background

High‐frequency electrical stimulation (HFS) of the human forearm evokes analgesia to blunt pressure in the ipsilateral forehead, consistent with descending ipsilateral inhibitory pain modulation. The aim of the current study was to further delineate pain modulation processes evoked by HFS by examining sensory changes in the arm and forehead; investigating the effects of HFS on nociceptive blink reflexes elicited by supraorbital electrical stimulation; and assessing effects of counter‐irritation (electrically evoked pain at the HFS‐conditioned site in the forearm) on nociceptive blink reflexes before and after HFS.

Methods

Before and after HFS conditioning, sensitivity to heat and to blunt and sharp stimuli was assessed at and adjacent to the conditioned site in the forearm and on each side of the forehead. Nociceptive blink reflexes were also assessed before and after HFS with and without counter‐irritation of the forearm.

Results

HFS triggered secondary hyperalgesia in the forearm (a sign of central sensitization) and analgesia to blunt pressure in the ipsilateral forehead. Under most conditions, both HFS conditioning and counter‐irritation of the forearm suppressed electrically evoked pain in the forehead, and the amplitude of the blink reflex to supraorbital stimuli decreased. Importantly, however, in the absence of forearm counter‐irritation, HFS conditioning facilitated ipsilateral blink reflex amplitude to supraorbital stimuli delivered ipsilateral to the HFS‐conditioned site.

Conclusions

These findings suggest that HFS concurrently triggers hemilateral inhibitory and facilitatory influences on nociceptive processing over and above more general effects of counter‐irritation. The inhibitory influence may help limit the spread of sensitization in central nociceptive pathways.
Person‐centric clinical trials: An opportunity for the good clinical practice (GCP)‐practice‐based research network
Authors: Curro Frederick A. , Robbins Dennis A. , Millenson Michael L. , Fox Chester H. , Naftolin Frederick
Published: July 2013

Practice‐based research networks (PBRNs) can function as a platform for delivery of patient‐centered care consistent with the Patient Protection and Affordable Care Act. Patient‐centered (centric) clinical studies encourage the patient to be an integral part of study design and outcome. The patient's electronic health record contributes to the shared national health care data set. PBRNs integrate health care data in real time at the point of care and reflect the full context of the person's health. PBRNs designed under the principles of good clinical practice (GCP) validate studies related to comparative effectiveness research and drug development. PBRNs can generate large amounts of data from known patient histories so that side effects can be assessed in their totality. The larger and more diverse number of patients recruited suggests that point‐of‐care‐data, where both provider and patient participate in the treatment, may be more robust in that side effects, drug–drug interactions and number of concomitant medications used may be identified earlier in the development process. The GCP PBRN concept affords continuous patient information for both care and research purposes. These all contribute to an ethical approach for the pharmaceutical industry to generate clinical research data for regulatory submission and to contribute to a HIPAA‐compliant national database that could contribute to improved health care delivery and pharmacovigilance.
Returning to Graduate School: Expectations of Success, Values of the Degree, and Managing the Costs
Authors: Peters Diane L. , Daly Shanna R.
Published: July 2013

Background

Limited research exists on the experiences of engineering returners – those with undergraduate degrees who work for at least five years and return to academia for graduate degrees. Returners bring a different perspective to their graduate studies and postgraduate work than direct‐pathway students but face additional challenges.

Purpose

Our aim was to understand practitioners' decisions to return to graduate school and complete graduate degrees. Guided by expectancy value theory, we investigated their beliefs about their ability to succeed; the interest, attainment, and utility values returners placed on graduate school; the costs they experienced in returning; and the personal, programmatic, and cultural factors that mitigated these costs.

Design/Method

We employed a qualitative interpretivist approach to investigate the returning experience through semi‐structured interviews with 10 returners. We analyzed the results deductively, using expectancy value theory to understand participants' expectations of success and the values of those experiences, and inductively, to understand the types of costs that influenced the decision to return and complete graduate school.

Results

Utility value drove participants' decisions to return and complete graduate programs, and participants had a high expectancy of success in earning their graduate degrees. Four types of costs emerged from analysis of the interviews: intellectual, balance, cultural and environmental, and financial. Participants employed various strategies to mitigate these costs.

Conclusions

With the results of our study, potential returners can more effectively plan for success in the graduate environment, and universities can develop initiatives to better recruit returners and support their success.
Morphological and ultrastructural characterization of ionoregulatory cells in the teleost oreochromis niloticus following salinity challenge combining complementary confocal scanning laser microscopy and transmission electron microscopy using a novel prefixation immunogold labeling technique
Authors: Fridman Sophie , Rana Krishen J. , Bron James E.
Published: July 2013

Aspects of ionoregulatory or mitochondria‐rich cell (MRC) differentiation and adaptation in Nile tilapia yolk‐sac larvae following transfer from freshwater to elevated salinities, that is, 12.5 and 20 ppt are described. Investigations using immunohistochemistry on whole‐mount Nile tilapia larvae using anti‐ Na+/K+‐ATPase as a primary antibody and Fluoronanogold™ (Nanoprobes) as a secondary immunoprobe allowed fluorescent labeling with the high resolution of confocal scanning laser microscopy combined with the detection of immunolabeled target molecules at an ultrastructural level using transmission electron microscopy (TEM). It reports, for the first time, various developmental stages of MRCs within the epithelial layer of the tail of yolk‐sac larvae, corresponding to immature, developing, and mature MRCs, identifiable by their own characteristic ultrastructure and form. Following transfer to hyperosmotic salinities the density of immunogold particles and well as the intricacy of the tubular system appeared to increase. In addition, complementary confocal scanning laser microscopy allowed identification of immunopositive ramifying extensions that appeared to emanate from the basolateral portion of the cell that appeared to be correlated with the localization of subsurface tubular areas displaying immunogold labeled Na+/K+‐ATPase. This integrated approach describes a reliable and repeatable prefixation immunogold labeling technique allowing precise visualization of NaK within target cells combined with a 3D imaging that offers valuable insights into MRC dynamics at an ultrastructural level. Microsc. Res. Tech., 76:1016–1024, 2013. © 2013 Wiley Periodicals, Inc.
Investigating the P wave velocity structure beneath Harrat Lunayyir, northwestern Saudi Arabia, using double‐difference tomography and earthquakes from the 2009 seismic swarm
Authors: Hansen Samantha E. , DeShon Heather R. , Moore‐Driskell Melissa M. , Al‐Amri Abdullah M. S.
Published: July 2013

In 2009, a swarm of more than 30,000 earthquakes occurred beneath the Harrat Lunayyir lava field in northwest Saudi Arabia. This event was just one of several seismic swarms to occur in this region over the past decade. Surface deformation associated with the seismicity, modeled in previous studies using Interferometric Synthetic Aperture Radar (InSAR) data, is best attributed to the intrusion of a 10 km long dyke. However, little is known about the velocity structure beneath Harrat Lunayyir, making assessment of future seismic and volcanic hazards difficult. In this study, we use local double‐difference tomography to generate a P wave velocity model beneath Harrat Lunayyir and to more precisely locate earthquakes from the 2009 seismic swarm. A pronounced fast velocity anomaly, centered at ~15 km depth with a shallower extension to the N‐NW, is interpreted as an area of repeated magmatic intrusion. The crust surrounding the fast intrusion is slower than that suggested by broader‐scale models for the Arabian Shield. The largest magnitude events occurred early in the swarm, concentrated at shallow depths (~2–8 km) beneath northern Harrat Lunayyir, and these events are associated with the dyke intrusion. Later, deep earthquakes (~15 km) beneath the southern end of the study region as well as a group of intermediate‐depth events connecting the shallow and deep regions of seismicity occurred. These later events likely represent responses to the local stress conditions following the intrusion. Our results are unique since harrat magma systems are rarely imaged, and our observations, coupled with the seismic history in this region, suggest that future volcanic intrusions beneath Harrat Lunayyir are likely.
Characterization of open and closed volcanic systems in Indonesia and Mexico using InSAR time series
Authors: Chaussard E. , Amelung F. , Aoki Y.
Published: July 2013

We use 2007–2011 Advanced Land Observing Satellite (ALOS) data to perform an arc‐wide interferometric synthetic aperture radar (InSAR) time series survey of the Trans‐Mexican Volcanic Belt (TMVB) and to study time‐dependent ground deformation of four Indonesian volcanoes selected following the 2007–2009 study of Chaussard and Amelung (2012). Our objectives are to examine whether arc volcanoes exhibit long‐term edifice‐wide cyclic deformation patterns that can be used to characterize open and closed volcanic systems and to better constrain in which cases precursory inflation is expected. We reveal deformation cycles at both regularly active and previously inactive Indonesian volcanoes, but we do not detect deformation in the TMVB, reflecting a lower activity level. We identify three types of relationships between deformation and activity: inflation prior to eruption and associated with or followed by deflation (Kerinci and Sinabung), inflation without eruption and followed by slow deflation (Agung), and eruption without precursory deformation (Merapi, Colima, and Popocatépetl; at Merapi, no significant deformation is detected even during eruption). The first two cases correspond to closed volcanic systems and suggest that the traditional model of magmatic systems and eruptive cycles do apply to andesitic volcanoes (i.e., inflation and deflation episodes associated with magma accumulation or volatile exsolution in a crustal reservoir followed by eruptions or in situ cooling). In contrast, the last case corresponds to open volcanic systems where no significant pressurization of the magmatic reservoirs is taking place prior to eruptions and thus no long‐term edifice‐wide ground deformation can be detected. We discuss these results in terms of InSAR's potential for forecasting volcanic unrest.
Magma storage and migration associated with the 2011–2012 El Hierro eruption: Implications for crustal magmatic systems at oceanic island volcanoes
Authors: González Pablo J. , Samsonov Sergey V. , Pepe Susi , Tiampo Kristy F. , Tizzani Pietro , Casu Francesco , Fernández José , Camacho Antonio G. , Sansosti Eugenio
Published: July 2013

Starting in July 2011, anomalous seismicity was observed at El Hierro Island, a young oceanic island volcano. On 12 October 2011, the process led to the beginning of a submarine NW‐SE fissural eruption at ~15 km from the initial earthquake loci, indicative of significant lateral magma migration. Here we conduct a multifrequency, multisensor interferometric analysis of spaceborne radar images acquired using three different satellite systems (RADARSAT‐2, ENVISAT, and COSMO‐SkyMed (Constellation of Small Satellites for Mediterranean Basin Observation)). The data fully captures both the pre‐eruptive and coeruptive phases. Elastic modeling of the ground deformation is employed to constrain the dynamics associated with the magmatic activity. This study represents the first geodetically constrained active magmatic plumbing system model for any of the Canary Islands volcanoes, and one of the few examples of submarine volcanic activity to date. Geodetic results reveal two spatially distinct shallow (crustal) magma reservoirs, a deeper central source (9.5 ± 4.0 km), and a shallower magma reservoir at the flank of the southern rift (4.5 ± 2.0 km). The deeper source was recharged, explaining the relatively long basaltic eruption, contributing to the observed island‐wide uplift processes, and validating proposed active magma underplating. The shallowest source may be an incipient reservoir that facilitates fractional crystallization as observed at other Canary Islands. Data from this eruption supports a relationship between the depth of the shallow crustal magmatic systems and the long‐term magma supply rate and oceanic lithospheric age. Such a relationship implies that a factor controlling the existence/depth of shallow (crustal) magmatic systems in oceanic island volcanoes is the lithosphere thermomechanical behavior.
Generation of baroclinic tides over an isolated underwater bank
Authors: Vlasenko Vasiliy , Stashchuk Nataliya , Palmer Matthew R. , Inall Mark E.
Published: July 2013

The interaction of stratified tidal flow with an isolated bank (Jones Bank in the Celtic Sea) was investigated numerically and using observational data collected during the 25th research cruise of the R/V James Cook in July 2008. Two scenarios of observed wave generation, one with pure tidal forcing and another with an extra background current, were reproduced numerically and compared against the observational data. It was found that the tidal currents alone produced subcritical conditions for the first‐mode internal wave generation and supercritical flow for the second‐mode waves. Under these conditions, the first‐mode waves with amplitudes up to 10 m freely radiated from the bank, gradually transforming into attenuating dissipative baroclinic bores. Due to supercritical conditions, the second‐mode waves were arrested at the lee side of the bank for 3 h where they grew in amplitude (up to 35 m) and after their release propagated as a series of second‐mode internal solitary waves. The additional background current that was measured near the bank in the middle of June 2008 radically changed the conditions of wave generation. A strong southeastern current arrested the first‐mode perturbations at the NE flank of the bank for 2 h, where they grew in amplitude to almost 40 m and disintegrated into packets of first‐mode internal solitary waves after their release. For the second‐mode perturbations, the flow was substantially supercritical for more than one fourth of a tidal period so that these waves were just washed away from the generation site without any visible amplification.
N2O5 uptake coefficients and nocturnal NO2 removal rates determined from ambient wintertime measurements
Authors: Wagner N. L. , Riedel T. P. , Young C. J. , Bahreini R. , Brock C. A. , Dubé W. P. , Kim S. , Middlebrook A. M. , Öztürk F. , Roberts J. M. , Russo R. , Sive B. , Swarthout R. , Thornton J. A. , VandenBoer T. C. , Zhou Y. , Brown S. S.
Published: July 2013

Heterogeneous N2O5 uptake onto aerosol is the primary nocturnal path for removal of NOx (= NO + NO2) from the atmosphere and can also result in halogen activation through production of ClNO2. The N2O5 uptake coefficient has been the subject of numerous laboratory studies; however, only a few studies have determined the uptake coefficient from ambient measurements, and none has been focused on winter conditions, when the portion of NOx removed by N2O5 uptake is the largest. In this work, N2O5 uptake coefficients are determined from ambient wintertime measurements of N2O5 and related species at the Boulder Atmospheric Observatory in Weld County, CO, a location that is highly impacted by urban pollution from Denver, as well as emissions from agricultural activities and oil and gas extraction. A box model is used to analyze the nocturnal nitrate radical chemistry and predict the N2O5 concentration. The uptake coefficient in the model is iterated until the predicted N2O5 concentration matches the measured concentration. The results suggest that during winter, the most important influence that might suppress N2O5 uptake is aerosol nitrate but that this effect does not suppress uptake coefficients enough to limit the rate of NOx loss through N2O5 hydrolysis. N2O5 hydrolysis was found to dominate the nocturnal chemistry during this study consuming ~80% of nocturnal gas phase nitrate radical production. Typically, less than 15% of the total nitrate radical production remained in the form of nocturnal species at sunrise when they are photolyzed and reform NO2.
99mTc‐tricabonyl labeling of ofloxacin and its biological evaluation in Staphylococcus aureus as an infection imaging agent
Authors: Erfani Mostafa , Doroudi Alireza , Hadisi Leila , Andishmand Ali , Mirshojaei Seyedeh Fatemeh , Shafiei Mohammad
Published: July 2013

Even in recent decades, one of the major causes of death and unhealthiness in the whole world is infection and inflammation. The use of radiopharmaceuticals is a powerful tool in managing the patients with infectious diseases. In this study, ofloxacin as a second‐generation fluoroquinolone has been labeled with [99mTc(CO)3(H2O)3]+ core to formulate a suitable infection imaging agent. Ofloxacin was radiolabeled with 99mTc using carbonyl core. Radioligand chemical analysis involved HPLC methods. Radioconjugate stability and lipophilicity were determined. Binding with Staphylococcus aureus and biodistribution in infected mice for labeled compound were studied. The radioligand was characterized by HPLC, and its radiochemical purity was more than 90%. In vitro stability studies have shown the complex was stable at least 6 h after labeling at room temperature. The n‐octanol/water partition coefficient experiment exhibited logP = 1.52 ± 0.21 for 99mTc(CO)3‐ofloxacin. The complex showed specific binding to S. aureus. Biodistribution results showed that radioligand had high accumulation in the infected muscle in a mice (T/NT = 2.02 ± 0.12 at 4 h postinjection). On the basis of stability and infection site uptake ratio, suitability of this complex as a radiotracer for imaging of infections is recognized.
Simultaneous identification of historical pigments Prussian blue and indigo in paintings by electrospray mass spectrometry
Authors: Pauk Volodymyr , Havlíček Vladimír , Papoušková Barbora , Sulovský Petr , Lemr Karel
Published: July 2013

A new analytical protocol for identification of Prussian blue (PB) and indigo was proposed. Pigments useful for dating of artworks were detected by flow injection analysis/electrospray ionization mass spectrometry after alkalization of their suspensions in water, decomposition of PB to iron (III) hydroxide and hexacyanoferrate (II) and reduction of indigo to soluble leucoindigo using sodium dithionite. Limits of detection (PB 47 pg, indigo 59 pg) complied with requirements for analysis of microsamples of historical paintings. Potential of the developed method was proven in analysis of blue samples of two oil paintings from the 20th century. Further, PB was confirmed in a microsample from a painting of ‘Crucifixion’, St. Sebestian church on St. Hill in Mikulov, Czech Republic. Copyright © 2013 John Wiley & Sons, Ltd.
Indirect hydrogen analysis by gas chromatography coupled to mass spectrometry (GC–MS)
Authors: Varlet V. , Smith F. , Augsburger M.
Published: July 2013

Gas chromatography (GC) is an analytical tool very useful to investigate the composition of gaseous mixtures. The different gases are separated by specific columns but, if hydrogen (H2) is present in the sample, its detection can be performed by a thermal conductivity detector or a helium ionization detector. Indeed, coupled to GC, no other detector can perform this detection except the expensive atomic emission detector. Based on the detection and analysis of H2 isotopes by low‐pressure chemical ionization mass spectrometry (MS), a new method for H2 detection by GC coupled to MS with an electron ionization ion source and a quadrupole analyser is presented. The presence of H2 in a gaseous mixture could easily be put in evidence by the monitoring of the molecular ion of the protonated carrier gas. Copyright © 2013 John Wiley & Sons, Ltd.