bluuebunny/crossref_metadata_2025 huggingface dataset:
Exercise testing in children: Comparison in ventilatory thresholds changes with interval‐training
Authors: Mucci Patrick , Baquet Georges , Nourry Cédric , Deruelle Fabien , Berthoin Serge , Fabre Claudine
Published: September 2012

The aim of this investigation was, first, to examine comparatively the changes in first and second ventilatory thresholds (VT1 and VT2) and, secondly, to compare with peak oxygen uptake (${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $) changes following high‐intensity interval training (HIT) in prepubescent children. Eighteen prepubescent children (aged 10.1 ± 0.7 years) performed an incremental exhaustive exercise on a cycle ergometer with pulmonary gas exchange measurements before and after an 8‐week period. During this period, nine children (five girls and four boys; initial ${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $: 39.6 ± 6.0 ml O2 · min−1 · kg−1) took part in a HIT and nine other children (three girls and six boys; initial ${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $: 39.8 ± 7.8 ml O2 · min−1 · kg−1), considered as controls, were not trained. After the training period, VT1, VT2, and ${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $ were significantly (P < 0.01) improved (21%, 24%, and 14%, respectively) without significant changes in the control group. However, the changes in VT1 (ΔVT1 = +4.35 ± 4.36 ml O2 · min−1 · kg−1), VT2 (ΔVT1 = +7.17 ± 5.17 ml O2 · min−1 · kg−1), ${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $ ($\Delta {\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $ = +5.51 ± 4.17 ml O2 · min−1 · kg−1) induced by HIT in trained children were not related. In conclusion, for prepubescent children, in addition to VT1 and ${\dot {\rm {V}}}_{{\rm O}_{{\rm 2}} {\rm peak}} $, VT2 can also be significantly improved by training. Therefore, HIT represents a good way to obtain great improvement in these parameters in only 8 weeks. However, the time courses of these aerobic fitness parameters are dissociated, which implies the need to differentiate among them during aerobic fitness exercise testing. Pediatr Pulmonol. 2013; 48:809–816. © 2012 Wiley Periodicals, Inc.
Respiratory health outcomes 1 year after admission with severe lower respiratory tract infection
Authors: Trenholme A.A. , Byrnes C.A. , McBride C. , Lennon D.R. , Chan‐Mow F. , Vogel A.M. , Stewart J.M. , Percival T.
Published: September 2012

Severe lower respiratory infection (LRI) is believed to be one precursor of protracted bacterial bronchitis, chronic moist cough (CMC), and chronic suppurative lung disease. The aim of this study was to determine and to describe the presence of respiratory morbidity in young children 1 year after being hospitalized with a severe LRI. Children aged less than 2 years admitted from August 1, 2007 to December 23, 2007 already enrolled in a prospective epidemiology study (n = 394) were included in this second study only if they had a diagnosis of severe bronchiolitis or of pneumonia with no co‐morbidities (n = 237). Funding allowed 164 to be identified chronologically, 131 were able to be contacted, and 94 agreed to be assessed by a paediatrician 1 year post index admission. Demographic information, medical history and a respiratory questionnaire was recorded, examination, pulse oximetry, and chest X‐ray (CXR) were performed. The predetermined primary endpoints were; (i) history of CMC for at least 3 months, (ii) the presence of moist cough and/or crackles on examination in clinic, and (iii) an abnormal CXR when seen at a time of stability. Each CXR was read by two pediatric radiologists blind to the individuals' current health. Results showed 30% had a history of CMC, 32% had a moist cough and/or crackles on examination in clinic, and in 62% of those with a CXR it was abnormal. Of the 81 children with a readable follow‐up X‐ray, 11% had all three abnormal outcomes, and 74% had one or more abnormal outcomes. Three children had developed bronchiectasis on HRCT. The majority of children with a hospital admission at <2 years of age for severe bronchiolitis or pneumonia continued to have respiratory morbidity 1 year later when seen at a time of stability, with a small number already having sustained significant lung disease. Pediatr Pulmonol. 2013; 48:772–779. © 2012 Wiley Periodicals, Inc.
Effects of Cry34/35Ab1 corn on the survival and development of western corn rootworm, Diabrotica virgifera virgifera
Authors: Rudeen Melissa L , Gassmann Aaron J
Published: September 2012

Background

The western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major agricultural pest that is managed with transgenic corn, Zea mays L., expressing genes from Bacillus thuringiensis Berliner (Bt). The effects of Bt corn producing Cry34/35Ab1 (event DAS‐59122–7) and entomopathogens on the survival and development of larval D. v. virgifera were examined in laboratory, field and greenhouse experiments.

Results

Larvae preferred non‐Bt over Bt corn in a laboratory experiment, and there was higher recovery from non‐Bt corn than from Bt corn in a field experiment. In a greenhouse study, survival at 17 days did not differ significantly among non‐Bt corn, Bt corn and a blend of Bt and non‐Bt corn, but development was delayed on Bt corn. Older larvae fed non‐Bt corn had lower survival when entomopathogenic nematodes were added, but no other effects of pathogen were detected.

Conclusion

Bt corn producing Cry34/35Ab1 delayed larval development of D. v. virgifera and deterred feeding. In a mixture of Bt and non‐Bt corn, larval development and survival were similar to non‐Bt corn alone, suggesting that non‐Bt plants in a blended refuge or a pure stand may produce a similar number of adult insects, and that timing of adult emergence may also be similar. © 2012 Society of Chemical Industry
Origin of photoinduced defects in glassy As2S3 under band gap illumination studied by Raman scattering: A revisory approach
Authors: Yannopoulos S. N. , Andrikopoulos K. S. , Kastrissios D. Th. , Papatheodorou G. N.
Published: September 2012

We report on a detailed study of the photostructural changes in bulk glassy As2S3 under vacuum using Raman scattering. Various excitation energies were employed to achieve resonance and off‐resonance conditions. Temperature‐induced structural changes were also investigated at conditions far from resonance, in order to clarify the role of bandgap light on the induced structural changes. Bandgap illumination induces structural changes much stronger than those reported up to now for this glass. The absence of oxygen is considered as a possible cause of this observation. The kinetics of the structural changes was monitored in the course of bandgap illumination and the role of in situ annealing was considered. The formation of As–As bonds is the main light‐induced structural change, which if contemplated together with the absence of S–S bond formation points to the failure of models adopting realgar‐type structures and calls for new structural defects based on centers with increased coordination number. The vibrational features of few such defects based on over‐coordinated As centers are discussed in conjunction with the present experimental findings.
Effects of germanium doping on the boron‐oxygen complex formation in silicon solar cells
Authors: Tanay Florent , Dubois Sébastien , Enjalbert Nicolas , Veirman Jordi , Gidon Pierre , Périchaud Isabelle
Published: September 2012

The light‐induced degradation (LID) due to the boron–oxygen (B–O) complexes is particularly harmful for solar cells made from the boron‐doped p ‐type Czochralski silicon (Cz‐Si). Many studies focused on this phenomenon and some processes have been proposed to reduce it. Recently, Cz‐Si voluntarily doped with germanium (Ge) was used to inhibit the effect of the B–O complexes activation. We studied here both conventional Cz‐Si (CZ) and Ge‐doped Cz‐Si (GCZ), and compared their sensitivity to the LID. The first result was that solar cells produced with GCZ had the same performances than solar cells made with CZ despite the impurities like iron unintentionally introduced in GCZ by the Ge powder. Then, we found that the degradation under illumination of the efficiency was lower in GCZ only for the solar cells produced from the last solidified part of the ingot (where the Ge content is the highest). These differences were correlated with the amount of interstitial oxygen (Oi) which was found to be lower for the GCZ wafer, possibly due to the formation of Ge–Oi related defects and/or to Ge‐enhanced oxygen precipitation effects. At the cell level, we also compared the kinetics of the LID in both materials and confirmed that the degradation was slower in GCZ. Finally, we showed that the mechanism of lightinduced regeneration (LIR) also occurs in GCZ solar cells, with similar kinetics with respect to conventional Cz‐Si cells (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of porous silicon passivation layer and TiO2 coating on the optoelectronic properties of multicrystalline Si substrate
Authors: Janene N. , Hajjaji A. , Ben Rabha M. , El Khakani M. A. , Bessais B. , Gaidi M.
Published: September 2012

In this work a novel passivation technique is proposed for multicrystalline silicon wafers for the purpose of solar cell application. The new method combines the use of double treatment based on porous Si and TiO2 passivation. Porous silicon (PS) was prepared by electrochemical anodization of multi crystalline substrates (mc‐Si) under different conditions of current density (The current density used is between 3 and 50 mA/cm2). It was demonstrated that the porosity increases with increasing current density from 27, 66% to 81%. TiO2 nanoparticles with different nanometric sizes were incorporated inside pores by the way of the pulsed laser deposition (PLD) technique. The deposited layers have been characterized by spectrophotometry, Fourier transform infrared spectroscopy (FTIR) analysis. It was found that the binary structure of TiO2/PS minimizes the average reflectivity of the mc‐Si substrates from 36% for bare multi crystalline silicon to around 14% for treated substrate. The TiO2/porous Si treated samples present high photoluminescence intensity and an enhancement of the optoelectronic properties. As a result the effective minority carrier lifetime shows a strong improvement after the combined treatment (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Distributed access control policies for spectrum sharing
Authors: Baldini Gianmarco , Fovino Igor Nai , Braghin Stefano , Trombetta Alberto
Published: September 2012

Cognitive radio is a novel wireless communication technology that allows for adaptive configuration of the reception parameters of a terminal, based on the information collected from the environment. Cognitive radio technology can be used in innovative spectrum management approaches such as spectrum sharing, where radio frequency spectral bands can be shared among various users through a dynamic exclusive‐use spectrum access model. Spectrum sharing can be applied to various scenarios in the commercial, public safety and military domain. In some scenarios, spectrum sharing demands a mechanism for expressing and enforcing access control policies for the allocation of resources including spectral bands. The access control polices should state what are the available resources (e.g., transmission/reception bandwidths), what are the users that are allowed to access them and under what conditions. However, because of the intrinsically highly dynamic nature of specific scenarios (e.g., public safety, military), where parties with various levels of authority may suddenly appear, it may be difficult to establish in advance what are the most suitable access control policies. Trust negotiation is a well‐known approach for expressing and enforcing distributed access control policies that depend on two or more parties. In this work, we present a trust negotiation‐based framework that allows for the definition of highly expressive and flexible distributed access control policies for the allocation of spectrum resources. Copyright © 2012 John Wiley & Sons, Ltd.
Needle‐knife precut papillotomy with a small incision over a pancreatic stent improves the success rate and reduces the complication rate in difficult biliary cannulations
Authors: Kubota Kensuke , Sato Takamitsu , Kato Shingo , Watanabe Seitaro , Hosono Kunihiro , Kobayashi Noritoshi , Hisatomi Kantaro , Matsuhashi Nobuyuki , Nakajima Atsushi
Published: September 2012

Background

Successful precut sphincterotomy (PS) in difficult biliary cannulation (DBC) requires a large incision for deroofing the papilla. However, the high complication rate poses a substantial problem, in addition to the need for expert skills. Pancreatic stent placement could facilitate this procedure. Needle‐knife precut papillotomy with a small incision using a layer‐by‐layer method over a pancreatic stent (NKPP‐SIPS) could potentially improve the success rate and reduce the complication rate of PS.

Aims

To validate the efficacy, feasibility and safety of NKPP‐SIPS in DBC.

Methods

Therapeutic endoscopic retrograde cholangiopancreatography with a naïve papilla was performed in 1619 cases between May 2004 and July 2011. We prospectively divided the patients chronologically, in terms of the period during which the procedure was performed, into two groups: group A; needle‐knife precut papillotomy (NKPP) performed between April 2004 and October 2006; group B; NKPP‐SIPS performed between November 2006 and July 2011. The success rates and complication rates were evaluated. NKPP was performed without pancreatic stent placement and the cut was made starting at the papillary orifice, extended upward over a length of more than 5—10 mm for deroofing the papilla. On the other hand, in NKPP‐SIPS, a pancreatic stent was placed initially as a guide, and to prevent post‐ERCP pancreatitis, the incision was begun at the papillary orifice in a layer‐by‐layer fashion and extended upward in 1—2 mm increments, not going beyond the oral protrusion, finally measuring less than 5 mm in length.

Results

PS was performed in 8.3 % of the patients (134/1619). The cannulation success rate of PS in the entire group was 94.0 % (126/134). NKPP and NKPP‐SIPS were performed in 36 and 98 of the patients, respectively. There was one case of major bleeding in group A, and no severe complications in group B. The success rates of bile duct cannulation increased from 86.1 % (31/36) in group A to 96.9 % (95/98) in group B (p = 0.0189). The overall complication rate of PS was YC 33 % (12/36) in group A (major bleeding 8.3 %; mild to moderate pancreatitis 19.4 %; perforation requiring surgery 2.8 %), and 7.1 % (7/98) in group B (mild to moderate pancreatitis 6.1 %; minor perforation 1 %) (p < 0.001).

Conclusions

NKPP‐SIPS has significantly improved the success rate and reduced the complication rate of DBC, proving that a small incision starting at the orifice of the PS is sufficient, feasible and safe in DBC, when a pancreatic stent is inserted at the outset.
The role of Bayesian philosophy within Bayesian model selection
Authors: Sprenger Jan
Published: September 2012

Bayesian model selection has frequently been the focus of philosophical inquiry (e.g., Forster, Br J Philos Sci 46:399–424, 1995; Bandyopadhyay and Boik, Philos Sci 66:S390–S402, 1999; Dowe et al., Br J Philos Sci 58:709–754, 2007). This paper argues that Bayesian model selection procedures are very diverse in their inferential target and their justification, and substantiates this claim by means of case studies on three selected procedures: MML, BIC and DIC. Hence, there is no tight link between Bayesian model selection and Bayesian philosophy. Consequently, arguments for or against Bayesian reasoning based on properties of Bayesian model selection procedures should be treated with great caution.
Optimization of integrated pest management for powdery mildew (Unincula necator) control in a vineyard based on a combination of phenological, meteorological and aerobiological data
Authors: FERNÁNDEZ-GONZÁLEZ M. , RODRÍGUEZ-RAJO F. J. , ESCUREDO O. , AIRA M. J.
Published: September 2012

Powdery mildew is one of the most important vineyard diseases. Infection requires the interaction of a susceptible host (a vine in a phenological phase susceptible to the pathogen), a virulent pathogen (the fungusUncinula necator(Schw.) Burr) and an environment favourable for disease development (optimal meteorological conditions). The aim of the present study was the implementation of a system to predict powdery mildew infection periods in order to optimize and reduce the application of pesticide treatments in a vineyard. The study was conducted in a vineyard of the ‘Ribeiro’ Designation of Origin region located in north-western Spain from 2006 to 2011, during the Vitis vegetative period. The phenological study was conducted following the BBCH phenological scale and infection risk index (IRI) was calculated based on the maximum temperature. Aerobiological sampling was performed using a LANZONI VPPS-2000 volumetric trap. The results of the study show that the critical phenological stages for powdery mildew infection are 5 (inflorescence emergence), 6 (flowering) and 7 (development of fruit), as consequence of the high susceptibility of the vine. The IRI allows determination of the periods in which the meteorological conditions could facilitate fungal attacks during the aforementioned phenological phases. Finally, the aerobiological model helps to identify and predict the times of real infection risk among the possible periods described by the IRI with high accuracy, in order to avoid possible reappearance of infection symptoms in the vine. The combination of these three variables provides a valuable tool to establish an accurate, modern, integrated pest-management strategy in a vineyard.
Glomangiopericytoma (sinonasal-type haemangiopericytoma)
Authors: Oosthuizen J C , Kennedy S , Timon C
Published: September 2012

Background:

Glomangiopericytoma is a rare sinonasal tumour of perivascular myoid phenotype, which accounts for less than 1 per cent of all sinonasal tumours.

Objective:

Discussion of the clinical presentation, histopathological features and advances in the management of sinonasal and skull base glomangiopericytoma.

Case report:

A 32-year-old woman presented with worsening nasal obstruction, anosmia, severe frontal headaches and right-sided proptosis. Radiographic and endoscopic examination revealed a right-sided, vascular mass involving the nasal cavity, paranasal sinuses and anterior skull base. Histopathological features were consistent with a glomangiopericytoma. Complete endoscopic resection with free margins was achieved.

Conclusion:

Glomangiopericytomas are rare, vascular, sinonasal tumours. Successful management depends on complete resection, traditionally achieved via an open approach. However, recent advances in endoscopic surgical approaches have enabled complete endoscopic resection of these tumours, minimising morbidity and facilitating subsequent surveillance of the operative site.
Changing Social Security in the US: Rising Insecurity?
Authors: Harrington Meyer Madonna
Published: September 2012

Although poverty rates among the elderly in the US are at an all-time low, many face rising fiscal insecurity. The US welfare state is being remodeled in market-friendly ways that maximise individual choice, risk, and responsibility, rather than family friendly ways that maximise shared risk and responsibility and reduce insecurity. This article analyses how each of the main sources of income for the aged are being either frozen or shrunk in ways that are likely to increase inequality and insecurity in the years ahead among the elderly, particularly those who are female, black and/or Hispanic, and unmarried. The article assesses various policy changes for their capacity to either increase or decrease financial insecurity and inequality, particularly for those with a life time of lower earnings, more labour force disruptions and greater responsibility for providing unpaid care work for the young, disabled or frail elderly.
On arithmetic families of filtered -modules and crystalline representations
Authors: Hellmann Eugen
Published: September 2012

We consider stacks of filtered$\varphi $-modules over rigid analytic spaces and adic spaces. We show that these modules parameterize$p$-adic Galois representations of the absolute Galois group of a$p$-adic field with varying coefficients over an open substack containing all classical points. Further, we study a period morphism (defined by Pappas and Rapoport) from a stack parameterizing integral data, and determine the image of this morphism.
Reoccupation of floodplains by rivers and its relation to the age structure of floodplain vegetation
Authors: Konrad Christopher P.
Published: September 2012

River channel dynamics over many decades provide a physical control on the age structure of floodplain vegetation as a river occupies and abandons locations. Floodplain reoccupation by a river, in particular, determines the interval of time during which vegetation can establish and mature. A general framework for analyzing floodplain reoccupation and a time series model are developed and applied to five alluvial rivers in the United States. Channel dynamics in these rivers demonstrate time‐scale dependence with short‐term oscillations in active channel area in response to floods and subsequent vegetation growth and progressive lateral movement that accounts for much of the cumulative area occupied by the rivers over decades. Rivers preferentially reoccupy locations recently abandoned causing a decreasing probability of reoccupation with time since abandonment. For a typical case, a river is 10 times more likely to reoccupy an area it abandoned in the past decade than it is to reoccupy an area it abandoned 30 yrs ago. The decreasing probability of reoccupation over time is consistent with observations of persistent stands of late seral stage floodplain forest. A power function provides a robust approach for estimating the cumulative area occupied by a river and the age structure of riparian forests resulting from a specific historical sequence of streamflow in comparison to either linear or exponential alternatives.
Cluster multipoint study of the acceleration potential pattern and electrodynamics of an auroral surge and its associated horn arc
Authors: Marklund G. T. , Sadeghi S. , Li Bin , Amm O. , Cumnock J. A. , Zhang Y. , Nilsson H. , Masson A. , Karlsson T. , Lindqvist P.‐A. , Fazakerley A. , Lucek E. , Pickett J.
Published: September 2012

Cluster results are presented from the acceleration region of an auroral surge and connected horn arc, observed during an extended time period of substorm activity. The Cluster spacecraft crossed different magnetic local time (MLT) sectors of the surge and horn, with lag times of 2–10 min. Acceleration potential patterns are derived for the horn arc and for the double arc (surge and horn) at the surge front and deeper into the surge. The parallel potential drop of the horn arc ranged between 4 and 7 kV. At the surge front, two weakly coupled U‐potentials with parallel potential drops of 8 (7) kV and 7 (5) kV were derived for the surge and horn, respectively, from the C3 (C4) data. A similar, more coupled pattern was derived for the region deeper into the surge. We also address how the field‐aligned currents of the surge and horn system close in the ionosphere. The Cluster data allow almost simultaneous estimates of the latitudinal current closure at various MLT sectors. Significant net upward currents are derived for the horn and surge, whereas the currents at the surge front were found to be balanced. The net upward horn current is proposed to be fed by the zonal divergence of the westward Pedersen current in the horn, consistent with the acceleration potential decrease in the westward horn direction. The net upward surge current is proposed to be fed by the divergence of a westward electrojet and by localized downward currents adjacent to the surge.
Uncertainty in the velocity between the mass center and surface of Earth
Authors: Argus Donald F.
Published: September 2012

Using spectral analysis and data decimation, we estimate the uncertainty in the velocity between the cumulative mass center of Earth (CM) and geodetic sites on Earth's surface. Knowing this velocity is crucial for evaluating space geodetic observations of continental uplift and subsidence in terms of postglacial rebound and sea level rise. We find SLR observations of satellite LAGEOS to constrain the X and Y components of the velocity of CM to ±0.4 mm/yr and the Z component to ±0.9 mm/yr. (95% confidence limits, X is in the direction of 0°N 0°E, Y of 0°N 90°E, and Z of 90°N.) The uncertainty in Z is high, so that the estimate includes the independent inference made jointly using site velocities, the rigid plate hypothesis, and models of postglacial rebound that the true velocity of CM has a Z component of 0.5–1.0 mm/yr relative to that in ITRF2008. Uncertainty in scale rate, an intermediate parameter in the determination of an ITRF, is ±0.36 mm/yr for VLBI, ±0.52 mm/yr for SLR, and ±0.20 mm/yr for GPS. The scale of GPS depends on that of VLBI and SLR, but the low GPS uncertainty indicates that GPS results are, for the first time, unbiased by changing satellite Block types, evidently due to newly incorporated satellite phase center variations. GPS constrains the velocity of CM nearly as well as SLR, representing a technical advance given that a GPS satellite is not a sphere and responds strongly to solar radiation pressure.
Externally triggered renewed bubble nucleation in basaltic magma: The 12 October 2008 eruption at Halema‘uma‘u Overlook vent, Kīlauea, Hawai‘i, USA
Authors: Carey Rebecca J. , Manga Michael , Degruyter Wim , Swanson Donald , Houghton Bruce , Orr Tim , Patrick Matthew
Published: September 2012

From October 2008 until present, dozens of small impulsive explosive eruptions occurred from the Overlook vent on the southeast side of Halema‘uma‘u Crater, at Kīlauea volcano, USA. These eruptions were triggered by rockfalls from the walls of the volcanic vent and conduit onto the top of the lava column. Here we use microtextural observations and data from clasts erupted during the well‐characterized 12 October 2008 explosive eruption at Halema‘uma‘u to extend existing models of eruption triggering. We present a potential mechanism for this eruption by combining microtextural observations with existing geophysical and visual data sets. We measure the size and number density of bubbles preserved in juvenile ejecta using 2D images and X‐ray microtomography. Our data suggest that accumulations of large bubbles with diameters of >50μm to at least millimeters existed at shallow levels within the conduit prior to the 12 October 2008 explosion. Furthermore, a high number density of small bubbles <50 μm is measured in the clasts, implying very rapid nucleation of bubbles. Visual observations, combined with preexisting geophysical data, suggest that the impact of rockfalls onto the magma free surface induces pressure changes over short timescales that (1) nucleated new additional bubbles in the shallow conduit leading to high number densities of small bubbles and (2) expanded the preexisting bubbles driving upward acceleration. The trigger of eruption and bubble nucleation is thus external to the degassing system.
A test of the advection‐condensation model for subtropical water vapor using stable isotopologue observations from Mauna Loa Observatory, Hawaii
Authors: Hurley John V. , Galewsky Joseph , Worden John , Noone David
Published: September 2012

Subtropical humidity plays a critical role in the radiative balance of the planet, and there is a need for adequate description of the controls on water vapor distributions. This study tests whether an advection‐condensation model, combined with Rayleigh distillation, can describe observed humidity and water vapor isotope ratios of the subtropical free troposphere. A field campaign, from 9 October to 6 November, 2008, included continuous in situ measurement of water vapor stable isotope ratios at the NOAA Mauna Loa Observatory (MLO), Hawaii. Last saturation patterns for air at the MLO were determined using both Lagrangian back‐trajectory and Eulerian model techniques. Last saturation occurs primarily along midlatitude storm tracks (∼65%), and secondarily near Hawaii (∼10%) within mesoscale convective systems. Periods of lowerδDvalues at MLO correspond to extra‐tropical last saturation, while elevatedδD corresponds with saturation locations near Hawaii. To a first order, the conditions of last saturation are found to set not only the humidity but also the water vapor isotope ratio. In the absence of mixing, reconstructed q and δD values underestimate the observations. Experimental reconstructions demonstrate that variable amounts of mixing within the free troposphere and about 2% vapor influx mixing per hour from the boundary layer can explain the observed q and δD values. A last saturation model provides a reasonable description of humidity and water vapor isotope ratios of the subtropical free troposphere and results are sensitive to the treatment of mixing of air parcels last saturated in distinctly different regions of the atmosphere.
Oxidative aging of mixed oleic acid/sodium chloride aerosol particles
Authors: Dennis‐Smither Benjamin J. , Miles Rachael E. H. , Reid Jonathan P.
Published: September 2012

Studies of the oxidative aging of single mixed component aerosol particles formed from oleic acid (OL) and sodium chloride over a range of relative humidities (RH) and ozone concentrations by aerosol optical tweezers are reported. The rate of loss of OL and changes in the organic phase volume are directly measured, comparing particles with effloresced and deliquesced inorganic seeds. The kinetics of the OL loss are analyzed and the value of the reactive uptake coefficient of ozone by OL is compared to previous studies. The reaction of OL is accompanied by a decrease in the particle volume, consistent with the evaporation of semivolatile products over a time scale of tens of thousands of seconds. Measurements of the change in the organic phase volume allow the branching ratio to involatile components to be estimated; between 50 and 85% of the initial organic volume remains involatile, depending on ozone concentration. The refractive index (RI) of the organic phase increases during and after evaporation of volatile products, consistent with aging followed by a slow restructuring in particle morphology. The hygroscopicity of the particle and kinetics of the response of the organic phase to changes in RH are investigated. Both size and RI of unoxidized and oxidized particles respond promptly to RH changes with values of the RI consistent with linear mixing rules. Such studies of the simultaneous changes in composition and size of mixed component aerosol provide valuable data for benchmarking kinetic models of heterogeneous atmospheric aging.
Rates of temperature change of airless landscapes and implications for thermal stress weathering
Authors: Molaro Jamie , Byrne Shane
Published: September 2012

Thermal stress weathering may play a role in the evolution of terrestrial‐planet landscapes, particularly those without atmospheres, by contributing to rock breakdown, regolith production, and crater degradation. Damage occurs in the form of microscopic cracks that result from a thermal cycle or thermal shock. Terrestrial studies typically evaluate the efficacy of this process by measuring the rate of surface temperature change (dT/dt), using a damage threshold of 2 K/min. While the extent of this damage is unknown, we investigate its relative efficacy by modeling rates of temperature change on various airless surfaces. The magnitude of dT/dt values is primarily controlled by sunrise/set durations on quickly rotating bodies, such as Vesta, and by distance to the sun on slowly rotating bodies, such as Mercury. The strongest temperature shocks are experienced by highly sloped east‐ or west‐facing surfaces. Hot thermal shocks (dT/dt > 0) tend to be stronger than cold shocks (dT/dt < 0), and on some bodies, daytime shadowing may produce higher dT/dt values than those caused by diurnal sunrise/set if the topography is optimally oriented. We find that high dT/dt values are not, however, always correlated with high temperature gradients within the rock. This adds to the ambiguity of the poorly understood damage threshold, warranting further research on the topic that goes beyond the simple 2 K/min criterion.
Distributed ice thickness and volume of all glaciers around the globe
Authors: Huss Matthias , Farinotti Daniel
Published: September 2012

A new physically based approach for calculating glacier ice thickness distribution and volume is presented and applied to all glaciers and ice caps worldwide. Combining glacier outlines of the globally complete Randolph Glacier Inventory with terrain elevation models (Shuttle Radar Topography Mission/Advanced Spaceborne Thermal Emission and Reflection Radiometer), we use a simple dynamic model to obtain spatially distributed thickness of individual glaciers by inverting their surface topography. Results are validated against a comprehensive set of thickness observations for 300 glaciers from most glacierized regions of the world. For all mountain glaciers and ice caps outside of the Antarctic and Greenland ice sheets we find a total ice volume of 170 × 103 ± 21 × 103 km3, or 0.43 ± 0.06 m of potential sea level rise.
A comparison of IRI‐TEC predictions with GPS‐TEC measurements over Nsukka, Nigeria
Authors: Okoh Daniel , Eze Ambrose , Adedoja Oluweseye , Okere Bonaventure , Okeke P. N.
Published: September 2012

The International Reference Ionosphere (IRI) model has been widely adopted as the international standard for specifying ionospheric parameters. An evaluation on the performance of the IRI model (version 2007) over Nsukka, Nigeria (Geographic: 6.87°N, 7.38°E; Geomagnetic: 8.47°N, 81.07°E) is presented in this work. We compare Total Electron Content (TEC) values for year 2010 from the IRI model with corresponding TEC data from the SCINDA (Scintillation Network Decision Aid) GPS receiver installed at Nsukka so as to evaluate the performance of the model over the Nsukka region. Given the proliferation of dual‐frequency GPS receivers over the African continent, data from these equipment is proposed for use in TEC modeling over the continent together with the IRI model. Knowledge on the performance of the IRI over various regions of the continent will inform the extent to which the model will be used. The development of more accurate TEC maps find useful applications in enhancing the extent to which ionospheric influences on radio signals (as in single frequency GPS receivers) are corrected. Our results show very good diurnal correlations (above 0.88) between the IRI‐TEC predictions and the GPS‐TEC measurements for the days examined, and so reveal the potential of the IRI model as a good candidate for an enhanced TEC modeling over the African region.
Combined Arterial Spin Labeling and Diffusion-Weighted Imaging for Noninvasive Estimation of Capillary Volume Fraction and Permeability-Surface Product in the Human Brain
Authors: Hales Patrick W , Clark Chris A
Published: September 2012

A number of two-compartment models have been developed for the analysis of arterial spin labeling (ASL) data, from which both cerebral blood flow ( CBF) and capillary permeability-surface product ( PS) can be estimated. To derive values of PS, the volume fraction of the ASL signal arising from the intravascular space ( vbw) must be known a priori. We examined the use of diffusion-weighted imaging (DWI) and subsequent analysis using the intravoxel incoherent motion model to determine vbw in the human brain. These data were then used in a two-compartment ASL model to estimate PS. Imaging was performed in 10 healthy adult subjects, and repeated in five subjects to test reproducibility. In gray matter (excluding large arteries), mean voxel-wise vbw was 2.3 ± 0.2 mL blood/100 g tissue (all subjects mean ± s.d.), and CBF and PS were 44 ± 5 and 108 ± 2 mL per 100 g per minute, respectively. After spatial smoothing using a 6-mm full width at half maximum Gaussian kernel, the coefficient of repeatability of CBF, vbw and PS were 8 mL per 100 g per minute, 0.4 mL blood/100 g tissue, and 13 mL per 100 g per minute, respectively. Our results show that the combined use of ASL and DWI can provide a new, noninvasive methodology for estimating vbw and PS directly, with reproducibility that is sufficient for clinical use.
Using Standards-Based Instruction To Teach Language to Children Who Use AAC
Authors: Henneberry Solana , Kelso Jennifer , Soto Gloria
Published: September 2012

Federal legislation has increasingly mandated that students with disabilities have access to the general education curriculum. The general education curriculum should be the primary content and context of the education and therapeutic intervention for students who use AAC. Special educators, including speech and language pathologists, need to encapsulate the essence of Common Core Content Standards and the general education curriculum to address the content and language needs of AAC users. The interconnection of curriculum content and language demands for the AAC user can be accomplished using readily available research based tools and strategies. We created a five-step process to help SLPs incorporate the general education curriculum into intervention to address language goals of AAC users: 1) assessment; 2) identifying grade level content standards from Common Core or state standards; 3) identifying the “essence” of the standard as it relates to language; 4) generating IEP goals; and 5) teaching language skills across curricular activities. We will provide examples of this process to address a general education standard and the language and curricular content goals for beginning communicators, context-dependent communicators and for students communicating independently. Collaboration between the SLP and educators by means of these steps supports student success across all curricular areas.
Ethical Concerns in Voluntourism in Speech-Language Pathology and Audiology
Authors: Hickey Ellen M. , McKenna Monica , Woods Celeste , Archibald Carmen
Published: September 2012

There is growing interest in short-term volunteering (i.e., volunteer tourism) to contribute to the development of speech-language pathology (SLP) and audiology (AUD) in global contexts. While this is exciting, professionals and students must be properly prepared for such trips to ensure cultural safety and avoid potential ethical concerns and pitfalls of neo-colonialist perspectives in working in resource-poor contexts. There is a burgeoning literature on volunteer tourism and medical tourism that can be used to assist us in planning and preparing for such work. Some examples from the first author's experiences in Malawi, Tanzania, and Kenya are used to illustrate some of the ethical concerns in SLPs' and AUDs' voluntourism. This article suggests that we attend to the motivations of volunteers, conduct training to ensure culturally safe and sustainable practices, and assist volunteers in coping with culture shock and re-entry shock. Research is needed to understand best practices in assessment and treatment in global contexts and best practices in pre- and post-trip training for SLP/AUD volunteers and students.
Functional transcriptomics of a migrating cell in
Caenorhabditis elegans
Authors: Schwarz Erich M. , Kato Mihoko , Sternberg Paul W.
Published: September 2012

In both metazoan development and metastatic cancer, migrating cells must carry out a detailed, complex program of sensing cues, binding substrates, and moving their cytoskeletons. The linker cell in
Caenorhabditis elegans
males undergoes a stereotyped migration that guides gonad organogenesis, occurs with precise timing, and requires the nuclear hormone receptor NHR-67. To better understand how this occurs, we performed RNA-seq of individually staged and dissected linker cells, comparing transcriptomes from linker cells of third-stage (L3) larvae, fourth-stage (L4) larvae, and
nhr-67
-RNAi–treated L4 larvae. We observed expression of 8,000–10,000 genes in the linker cell, 22–25% of which were up- or down-regulated 20-fold during development by NHR-67. Of genes that we tested by RNAi, 22% (45 of 204) were required for normal shape and migration, suggesting that many NHR-67–dependent, linker cell-enriched genes play roles in this migration. One unexpected class of genes up-regulated by NHR-67 was tandem pore potassium channels, which are required for normal linker-cell migration. We also found phenotypes for genes with human orthologs but no previously described migratory function. Our results provide an extensive catalog of genes that act in a migrating cell, identify unique molecular functions involved in nematode cell migration, and suggest similar functions in humans.
Dependence on nuclear factor of activated T-cells (NFAT) levels discriminates conventional T cells from Foxp3
+
regulatory T cells
Authors: Vaeth Martin , Schliesser Ulrike , Müller Gerd , Reissig Sonja , Satoh Kazuki , Tuettenberg Andrea , Jonuleit Helmut , Waisman Ari , Müller Martin R. , Serfling Edgar , Sawitzki Birgit S. , Berberich-Siebelt Friederike
Published: September 2012

Several lines of evidence suggest nuclear factor of activated T-cells (NFAT) to control regulatory T cells: thymus-derived naturally occurring regulatory T cells (nTreg) depend on calcium signals, the
Foxp3
gene harbors several NFAT binding sites, and the Foxp3 (Fork head box P3) protein interacts with NFAT. Therefore, we investigated the impact of NFAT on Foxp3 expression. Indeed, the generation of peripherally induced Treg (iTreg) by TGF-β was highly dependent on NFAT expression because the ability of CD4
+
T cells to differentiate into iTreg diminished markedly with the number of NFAT family members missing. It can be concluded that the expression of Foxp3 in TGF-β–induced iTreg depends on the threshold value of NFAT rather than on an individual member present. This is specific for iTreg development, because frequency of nTreg remained unaltered in mice lacking NFAT1, NFAT2, or NFAT4 alone or in combination. Different from expectation, however, the function of both nTreg and iTreg was independent on robust NFAT levels, reflected by less nuclear NFAT in nTreg and iTreg. Accordingly, absence of one or two NFAT members did not alter suppressor activity in vitro or during colitis and transplantation in vivo. This scenario emphasizes an inhibition of high NFAT activity as treatment for autoimmune diseases and in transplantation, selectively targeting the proinflammatory conventional T cells, while keeping Treg functional.
Rate and molecular spectrum of spontaneous mutations in the bacteriumEscherichia colias determined by whole-genome sequencing
Authors: Lee Heewook , Popodi Ellen , Tang Haixu , Foster Patricia L.
Published: September 2012

Knowledge of the rate and nature of spontaneous mutation is fundamental to understanding evolutionary and molecular processes. In this report, we analyze spontaneous mutations accumulated over thousands of generations by wild-typeEscherichia coliand a derivative defective in mismatch repair (MMR), the primary pathway for correcting replication errors. The major conclusions are (i) the mutation rate of a wild-typeE. colistrain is ∼1 × 10−3per genome per generation; (ii) mutations in the wild-type strain have the expected mutational bias for G:C > A:T mutations, but the bias changes to A:T > G:C mutations in the absence of MMR; (iii) during replication, A:T > G:C transitions preferentially occur with A templating the lagging strand and T templating the leading strand, whereas G:C > A:T transitions preferentially occur with C templating the lagging strand and G templating the leading strand; (iv) there is a strong bias for transition mutations to occur at 5′ApC3′/3′TpG5′ sites (where bases 5′A and 3′T are mutated) and, to a lesser extent, at 5′GpC3′/3′CpG5′ sites (where bases 5′G and 3′C are mutated); (v) although the rate of small (≤4 nt) insertions and deletions is high at repeat sequences, these events occur at only 1/10th the genomic rate of base-pair substitutions. MMR activity is genetically regulated, and bacteria isolated from nature often lack MMR capacity, suggesting that modulation of MMR can be adaptive. Thus, comparing results from the wild-type and MMR-defective strains may lead to a deeper understanding of factors that determine mutation rates and spectra, how these factors may differ among organisms, and how they may be shaped by environmental conditions.
Redox regulation of MAPK phosphatase 1 controls monocyte migration and macrophage recruitment
Authors: Kim Hong Seok , Ullevig Sarah L. , Zamora Debora , Lee Chi Fung , Asmis Reto
Published: September 2012

Monocytic adhesion and chemotaxis are regulated by MAPK pathways, which in turn are controlled by redox-sensitive MAPK phosphatases (MKPs). We recently reported that metabolic disorders prime monocytes for enhanced recruitment into vascular lesions by increasing monocytes’ responsiveness to chemoattractants. However, the molecular details of this proatherogenic mechanism were not known. Here we show that monocyte priming results in theS-glutathionylation and subsequent inactivation and degradation of MKP-1. Chronic exposure of human THP-1 monocytes to diabetic conditions resulted in the loss of MKP-1 protein levels, the hyperactivation of ERK and p38 in response to monocyte chemoattractant protein-1 (MCP-1), and increased monocyte adhesion and chemotaxis. Knockdown of MKP-1 mimicked the priming effects of metabolic stress, whereas MKP-1 overexpression blunted both MAPK activation and monocyte adhesion and migration induced by MCP-1. Metabolic stress promoted theS-glutathionylation of MKP-1, targeting MKP-1 for proteasomal degradation. Preventing MKP-1S-glutathionylation in metabolically stressed monocytes by overexpressing glutaredoxin 1 protected MKP-1 from degradation and normalized monocyte adhesion and chemotaxis in response to MCP-1. Blood monocytes isolated from diabetic mice showed a 55% reduction in MKP-1 activity compared with nondiabetic mice. Hematopoietic MKP-1 deficiency in atherosclerosis-prone mice mimicked monocyte priming and dysfunction associated with metabolic disorders, increased monocyte chemotaxis in vivo, and accelerated atherosclerotic lesion formation. In conclusion, we identified MKP-1 as a central redox-sensitive regulator of monocyte adhesion and migration and showed that the loss of MKP-1 activity is a critical step in monocyte priming and the metabolic stress-induced conversion of blood monocytes into a proatherogenic phenotype.
Wandering domains in quasiregular dynamics
Authors: Nicks Daniel
Published: September 2012

We show that wandering domains can exist in the Fatou set of a polynomial type quasiregular mapping of the plane. We also give an example of a quasiregular mapping of the plane, with an essential singularity at infinity, which has a sequence of wandering domains contained in a bounded part of the plane. This contrasts with the situation in the analytic case, where wandering domains are impossible for polynomials and, for transcendental entire functions, the existence of wandering domains in a bounded part of the plane has been an open problem for many years.