bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioaccumulation and toxicity of single-walled carbon nanotubes to benthic organisms at the base of the marine food chain
Authors: Parks Ashley N. , Portis Lisa M. , Schierz P. Ariette , Washburn Kate M. , Perron Monique M. , Burgess Robert M. , Ho Kay T. , Chandler G. Thomas , Ferguson P. Lee
Published: February 2013

As the use of single-walled carbon nanotubes (SWNTs) increases over time, so does the potential for environmental release. This research aimed to determine the toxicity, bioavailability, and bioaccumulation of SWNTs in marine benthic organisms at the base of the food chain. The toxicity of SWNTs was tested in a whole sediment exposure with the amphipod Ampelisca abdita and the mysid Americamysis bahia. In addition, SWNTs were amended to sediment and/or food matrices to determine their bioavailability and bioaccumulation through these routes in A. abdita, A. bahia, and the estuarine amphipod Leptocheirus plumulosus. No significant mortality to any species via sediment or food matrices was observed at concentrations up to 100 ppm. A novel near-infrared fluorescence spectroscopic method was utilized to measure and characterize the body burdens of pristine SWNTs in nondepurated and depurated organisms. We did not detect SWNTs in depurated organisms but quantified them in nondepurated A. abdita fed SWNT-amended algae. After a 28-d exposure to [14C]SWNT-amended sediment (100 µg/g) and algae (100 µg/g), [14C]SWNT was detected in depurated and nondepurated L. plumulosus amphipods at 0.50 µg/g and 5.38 µg/g, respectively. The results indicate that SWNTs are bioaccessible to marine benthic organisms but do not appear to accumulate or cause toxicity. Environ Toxicol Chem 2013;32:1270–1277. © 2013 SETAC
A screening study on the fate of fullerenes (nC60) and their toxic implications in natural freshwaters
Authors: Pakarinen Kukka , Petersen Elijah J. , Alvila Leila , Waissi-Leinonen Greta C. , Akkanen Jarkko , Leppänen Matti T. , Kukkonen Jussi V.K.
Published: February 2013

Increasing usage of fullerenes (C60) increases their opportunities to be released into the environment. For risk assessment, it is important to understand the environmental fate and ecotoxicological effects of C60. In the present study, fullerene settling was measured during a 1-yr period with 4 different lake waters and an artificial freshwater, and Daphnia magna immobilization and fullerene accumulation was also measured in each of the lake waters. Depending on the characteristics of the lake waters, fullerenes either exhibited extended water stability or settled rapidly; in all waters, there was a fraction that remained stable after 1 yr. Water stability was affected by the quality and molecular size distribution of dissolved natural organic matter (DNOM). Increasing DNOM molecular sizes with high aromatic content enhanced water stability. Immobilization of D. magna was generally quite low (under 20%) and highly variable after 24 h and 48 h at initial fullerene concentrations up to 10 mg/L. Substantial settling occurred during the time period for acute toxicity assays (i.e., 48 h), which should be anticipated when conducting toxicity assays. There were no significant differences in the quantity of accumulated fullerenes among the different lake waters at fullerene concentrations of 0.5 mg/L, but there were differences at 2 mg/L. Environ Toxicol Chem 2013;32:1224-1232. © 2013 SETAC
Genomic aberration patterns and expression profiles of squamous cell carcinomas of the vulva
Authors: Micci Francesca , Panagopoulos Ioannis , Haugom Lisbeth , Dahlback Hanne‐Sofie S. , Pretorius Maria E. , Davidson Ben , Abeler Vera M. , Tropé Claes G. , Danielsen Håvard E. , Heim Sverre
Published: February 2013

Little is known about the genomic abnormalities of squamous cell carcinomas (SCC) of the vulva and how they correlate with gene expression. We determined the genomic and expression profiles of 15 such SCC using karyotyping, DNA ploidy analysis, arrayCGH, and expression arrays. Four of the five cases with clonal chromosomal aberrations found by G‐banding showed highly abnormal karyotypes with multiple rearrangements. The imbalances scored by arrayCGH mapped to different chromosomes with losses being more common than gains. Frequent losses were scored from 3p and 8p whereas gains were frequent from 3q and 8q (loss of 8p with concomitant gain of 8q mostly occurred via 8q isochromosome formation). This is the first study of vulvar tumors using arrayCGH, and some frequent imbalances could be defined precisely. Of particular note were the sometimes large, sometimes small deletions of 3p and 9p which had minute areas in 3p14 and 9p23 as minimal commonly deleted regions. FHIT (3p14) and PTPRD (9p23) are the only genes here. They were both lost in seven cases, including homozygous losses of PTPRD in four tumors. Using qPCR we could demonstrate deregulation of the FHIT gene in tumor cells. Hence, this gene is likely to play a pathogenetic role in vulvar SCC tumorigenesis. Expression array analyses also identified a number of other genes whose expression profile was altered. Notable among the downregulated genes were MAL (in 2q11), KRT4 (in 12q13), and OLFM4 (in 13q14), whereas upregulated genes included SPRR2G (in 1q21.3) and S100A7A (in 1q21.3). © 2013 Wiley Periodicals, Inc.
Annual variation of coastal uplift in Greenland as an indicator of variable and accelerating ice mass loss
Authors: Yang Qian , Wdowinski Shimon , Dixon Timothy H.
Published: February 2013

Seasonal melting of the coastal part of the Greenland ice sheet is investigated using GPS vertical displacement data from coastal stations, combined with data on atmospheric and ocean temperatures. Using a high pass filter and cubic spline models, we estimate five variables describing seasonal uplift, a proxy for proximal mass loss, including duration of the melt season and the amount of summer uplift. Our analysis shows both temporal and spatial variations of uplift. Southern coastal Greenland experienced anomalously large uplift in summer 2010, implying significant melting that year. However, the northwest coast did not experience significant change in uplift at that time. Our data suggest that a combination of warm summer air temperature and warm sub‐surface ocean water temperature drove the large mass losses in 2010. Using the uplift pattern of 2008–2010, and comparing to atmospheric data and ocean water temperature data, we show that warm Irminger Water (IW) exerted significant influence on coastal melting in southeastern, southern and southwestern Greenland, reaching about 69°N in 2010. North of this, IW did not exert significant influence, in effect defining the northward limit of the sub‐polar gyre for that year. Thus, short‐term variability in the coastal GPS uplift signal can be used to infer an oceanographic parameter that has a critical influence on Greenland ice sheet health.
Investigating δ13C and Δ14C within Mytilus californianus shells as proxies of upwelling intensity
Authors: Ferguson J. E. , Johnson K. R. , Santos G. , Meyer L. , Tripati A.
Published: February 2013

Along the west coast of North America, climate and marine productivity is affected by seasonal to interannual changes in coastal upwelling. Our understanding of upwelling variability in the past is limited by the short duration of instrumental records. Changes in upwelling intensity are expected to affect the 13C/12C (δ13C) and radiocarbon (∆14C) content of marine dissolved inorganic carbon (DIC) due to variable mixing of old, upwelled seawater into surface waters. If seasonal variations in the δ13C of DIC are recorded in marine bivalve shells, they may provide valuable information about the extent of upwelling in the past. Comparison of modern Mytilus californianus shells from South California with a 5 year time series of coastal seawater ∆14C and δ13C allows an assessment of the suitability of Mytilus shell ∆14C and δ13C as proxies of upwelling intensity. We show that both absolute values and the seasonal range in seawater ∆14C are preserved in shell ∆14C, allowing its use as an indicator of upwelling intensity. Interpretation of shell δ13C is more problematic, with the δ13C of shell carbonate lower than seawater DIC by variable amounts (ranging from 0.5‰ to 1.5‰) due to the incorporation of metabolic carbon. The spatial and temporal variability observed in specimens that grew during the severe El Niño event of 1997–1998 demonstrates how a transect of shells spanning the western North American coastline can be used to reconstruct large‐scale patterns of seawater ∆14C variability for specific intervals of interest, such as those associated with El Niño Southern Oscillation–type phenomena.
Tidal modulation of continuous nonvolcanic seismic tremor in the Chile triple junction region
Authors: Gallego A. , Russo R. M. , Comte D. , Mocanu V. , Murdie R. E. , VanDecar J.C.
Published: February 2013

We located continuous seismic tremor with coherent amplitude wave trains in the Chile ridge subduction region (~46.5°S) in two clusters north and south of the Chonos Archipelago, between the Chile trench and the North Patagonian fore arc. Tremor persisted from December 2004 to February 2007 (the entire period of the Chile Ridge Subduction Project temporary seismic deployment), and lasted >17 h on six occasions. Tremor in the more active southern cluster reached a maximum duration of 48 h, and we observed no more than 3 continuous days without tremor activity. The cluster locations coincide with the surface projections of subducted transform faults formed at the Chile ridge. We also detected simultaneous, colocated low‐frequency microearthquakes with well‐defined impulsive waves within the tremor signals distributed from the surface to 40 km depth, suggesting tremors and earthquakes are part of the same process. The periodicity of tremor duration is strongly correlated with semidiurnal, diurnal, and long‐period tides, M2, N2, K1, O1, P1, and Mm (12.421 h, 12.000 h, 23.934 h, 25.819 h, 24.066 h, and 27.555 days, respectively). We found a significant correlation between tremor occurrence and Earth tides when tidal stress is calculated for the slip plane of a right‐lateral strike‐slip fault with strike N95°E, which is near parallel to subducted transform faults (N78°E) of the Chile ridge, indicating that the very small stresses resulting from the combination of ocean loading and solid Earth tides (~1 kPa) are sufficient to facilitate or suppress tremor production; tremors occur when shear stresses are maximum and wane or are low when shear stresses are minimum.
Active CO2 reservoir management for sustainable geothermal energy extraction and reduced leakage
Authors: Elliot Thomas R. , Buscheck Thomas A. , Celia Michael
Published: February 2013

Subsurface storage space is gaining recognition as a commodity for industrial and energy recovery operations. Geologic carbon dioxide (CO2) sequestration (GCS), wherein supercritical CO2 is injected into subsurface storage space, is under broad development in sedimentary reservoirs – particularly for hydrocarbon production, which uses supercritical CO2 as part of a carbon capture utilization and sequestration (CCUS) scheme. A novel CCUS operation is presented whereby we investigate the staged deployment of a coupled geothermal energy extraction (GEE)‐GCS operation in geothermal sedimentary reservoirs that re‐circulates extracted fluids. We identify sedimentary resources of the continental USA that have significant temperature at depths suitable for GCS. To predict the impact of a GEE‐GCS operation, a reservoir‐scale semi‐analytical model is used to simulate brine and CO2 migration through existing leakage pathways. With the goal of integrating GEE and GCS, a well‐site design exercise is undertaken, where we develop an idealized configuration for CO2 and brine production/reinjection wells. Results show potential geothermal sedimentary reservoirs suitable for GEE deployment exist in the continental USA; however the characteristics of each site should be investigated through a first stage GEE‐operation to determine GCS capacity. Our active CO2 reservoir management simulations demonstrate a decrease in injection and reservoir overpressures, a reduced migration of CO2 within the reservoir during active injection/extraction, and a reduced risk of brine and CO2 migration. With the use of the developed concentric‐ring well pattern, we demonstrate the longevity of thermal productivity from an ideal GEE site, while providing sufficient CO2 storage volume and trapping to act as a sequestration operation. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
Tropical Atlantic salinity variability: New insights from SMOS
Authors: Tzortzi E. , Josey S. A. , Srokosz M. , Gommenginger C.
Published: February 2013

Observations from the SMOS satellite are used to reveal new aspects of Tropical Atlantic sea surface salinity (SSS) variability. Over an annual cycle, the variability is dominated by eastern and western basin SSS “poles,” with seasonal ranges up to 6.5 pss (practical salinity scale), that vary out of phase by 6 months and largely compensate each other. A much smaller SSS range (0.08 pss) is observed for the region as a whole. The dominant processes controlling SSS variability are investigated using GPCPv2.2 precipitation (P), OAFlux evaporation (E), and Dai and Trenberth river flow (R) data sets. For the western pole, SSS varies in phase with P and lags R by 1–2 months; a more complex relationship holds for the eastern pole. The synthesis of novel satellite SSS data with E, P, and R enables a new approach to determining variability in Tropical freshwater fluxes and its potential impacts on the Atlantic ocean circulation.
Error statistics of Bayesian CO2 flux inversion schemes as seen from GOSAT
Authors: Chevallier Frédéric , O'Dell Christopher W.
Published: February 2013

Statistical modeling is at the root of CO2 atmospheric inversion systems, but few studies have focused on the quality of their assigned probability distributions. In this paper, we assess the reliability of the error models that are in input and in output of a specific CO2 atmospheric inversion system when it assimilates surface air sample measurements. We confront these error models with the mismatch between 4D simulations of CO2 and independent satellite retrievals of the total CO2 column. Taking all sources of uncertainties into account, it is shown that both prior and posterior errors are consistent with the actual departures, to the point that the theoretical error reduction brought by the surface measurements on the simulation of the Greenhouse gases Observing SATellite (GOSAT) total column measurements (15%) corresponds to the actual reduction seen over the midlatitude and tropical lands and over the tropical oceans.
Tropical American‐Atlantic forcing of austral summertime variability in the southern annular mode
Authors: Yu Bin , Lin Hai
Published: February 2013

The relative importance of tropical versus extratropical forcing on the southern annular mode (SAM) during the austral summer is explored using dry atmospheric model experiments with prescribed atmospheric forcing. The tropical forcing regions are determined based on areas of high observed correlations between atmospheric heating and the SAM. Diagnosed atmospheric forcing over the tropical America‐Atlantic is found to be the major tropical driver of the SAM trend and interannual variability. Synoptic eddies tend to reinforce and maintain the SAM‐associated circulation anomaly. Contribution of the tropical diagnosed forcing, as a whole, to the SAM trend over 1951–2010 is about one third in strength compared to that of the southern extratropical forcing processes.
Variability in the surface temperature and melt extent of the Greenland ice sheet from MODIS
Authors: Hall Dorothy K. , Comiso Josefino C. , DiGirolamo Nicolo E. , Shuman Christopher A. , Box Jason E. , Koenig Lora S.
Published: February 2013

Satellite‐derived moderate‐resolution imaging spectroradiometer (MODIS) ice‐surface temperature (IST) of the Greenland ice sheet shows a positive trend and two major melt events from 2000 to present. IST increased by ~0.55 ± 0.44°C/decade, with the greatest increase (~0.95 ± 0.44°C/decade) found in northwestern Greenland where coastal temperatures and mass loss are also increasing and outlet glaciers are accelerating. IST shows the highest rates of increase during summer (~1.35 ± 0.47°C/decade) and winter (~1.30 ± 1.53°C/decade), followed by spring (~0.60 ± 0.98°C/decade). In contrast, a decrease in IST was found in the autumn (~−1.49 ± 1.20°C/decade). The IST trends in this work are not statistically significant with the exception of the trend in northwestern Greenland. Major surface melt (covering 80% or more of the ice sheet) occurred during the 2002 and 2012 melt seasons where clear‐sky measurements show a maximum melt of ~87% and ~95% of the ice sheet surface, respectively. In 2002, most of the extraordinary melt was ephemeral, whereas in 2012 the ice sheet not only experienced more total melt, but melt was more persistent, and the 2012 summer was the warmest in the MODIS record (−6.38 ± 3.98°C). Our data show that major melt events may not be particularly rare during the present period of ice sheet warming.
Water use strategies of two co‐occurring tree species in a semi‐arid karst environment
Authors: Swaffer Brooke A. , Holland Kate L. , Doody Tanya M. , Li Chris , Hutson John
Published: February 2013

The flow of precipitation from the surface through to groundwater in karst systems is a complex process involving storage in the unsaturated zone and diffuse and preferential recharge pathways. The processes associated with this behaviour are not well understood, despite the prevalence of karst aquifers being used as freshwater supplies. As a result, uncertainty regarding the ecohydrological processes in this geological setting remains large. In response to the need to better understand the impact of woody vegetation on groundwater recharge, annual evapotranspiration (ET) rates and tree water sources were measured for two years above a shallow, fresh karst aquifer. Water use strategies of the co‐occurring Eucalyptus diversifolia subsp. diversifolia Bonpl. and Allocasuarina verticillata (Lam.) L. Johnson were investigated using a monthly water balance approach, in conjunction with measurement of the stable isotopes of water, leaf water potentials and soil matric potentials. The results suggest that it is unlikely groundwater resources are required to sustain tree transpiration, despite its shallow proximity to the soil surface, and that similarities exist between ET losses and the estimated long‐term average rainfall for this area. Irrespective of stand and morphological differences, E. diversifolia and A. verticillata ET rates showed remarkable convergence, demonstrating the ability of these co‐occurring species to maximise their use of the available precipitation, which avoids the requirement to differentiate between these species when estimating ET at a landscape scale. We conclude that the water holding capacity of porous geological substrates, such as those associated with karst systems, will play an important role in equilibrating annual rainfall variability and should be considered when assessing ecohydrological links associated with karst systems. Copyright © 2013 John Wiley & Sons, Ltd.
A stem‐branch topological codification for watershed subdivision and identification to support distributed hydrological modelling at large river basins
Authors: Liu Jiajia , Zhou Zuhao , Jia Yangwen , Wang Hao , Chen Xiangdong
Published: February 2013

Watershed subdivision is a useful discretization method for distributed hydrological models at large river basins. A subwatershed codification method, which is able to identify the subwatershed uniquely and reflect the topological relationship is desired. According to the previous literatures, there are two types of coding methods suitable for the subwatershed codification: the Pfafstetter‐group rules and the modified binary tree codification method. But, both of them have some shortcomings in theory and application. A new coding method named stem‐branch topological codification is developed to overcome these shortcomings, which is based on the stem‐branch topological structure of the drainage networks and capable of reflecting the river hierarchy. The basic coding elements of the method are river reaches in the drainage networks, which are not only generated by the tributary junctions, but also by the splitting points of hydrological factors (e.g. hydrological gauge stations and reservoirs). Also, the method could handle complex confluences (e.g. river reaches with more than two upstream inflows), which are rare under natural conditions, but more frequent in the digital elevation model extracted or artificial drainage networks (e.g. sewage systems or irrigation drainage networks). With the stem‐branch topological codification codes, it is easy to identify the upstream (or downstream) relationship between any two subwatersheds and to calculate the directly connected subwatershed codes. Also, if some changes have occurred in the drainage network, there is no need to recode the whole watershed, but by modifying the existed codes to form the new ones. Copyright © 2013 John Wiley & Sons, Ltd.
FUZZY DATA ENVELOPMENT ANALYSIS FOR PERFORMANCE EVALUATION OF AN IRRIGATION SYSTEM
Authors: Srinivasa Raju K. , Nagesh Kumar D.
Published: February 2013

Sixteen irrigation subsystems of the Mahi Bajaj Sagar Project, Rajasthan, India, are evaluated and selection of the most suitable/best is made using data envelopment analysis (DEA) in both deterministic and fuzzy environments. Seven performance‐related indicators, namely, land development works (LDW), timely supply of inputs (TSI), conjunctive use of water resources (CUW), participation of farmers (PF), environmental conservation (EC), economic impact (EI) and crop productivity (CPR) are considered. Of the seven, LDW, TSI, CUW, PF and EC are considered inputs, whereas CPR and EI are considered outputs for DEA modelling purposes. Spearman rank correlation coefficient values are also computed for various scenarios. It is concluded that DEA in both deterministic and fuzzy environments is useful for the present problem. However, the outcome of fuzzy DEA may be explored for further analysis due to its simple, effective data and discrimination handling procedure. It is inferred that the present study can be explored for similar situations with suitable modifications. Copyright © 2013 John Wiley & Sons, Ltd.
Comet‐FISH studies for evaluation of genetic damage of citalopram in somatic cells of the mouse
Authors: Attia Sabry M. , Ashour Abdelkader E. , Bakheet Saleh A.
Published: February 2013

Damage to DNA can lead to many different acute and chronic pathophysiological conditions, ranging from cancer to endothelial damage. The present study was designed to evaluate the DNA damage of an antidepressant drug, citalopram, at the recommended human doses in somatic cells of mice in vivo. Mice exposed to citalopram at varying oral doses of 12 or 24 mg kg–1 for 7 days exhibited a significant increase in the level of DNA‐strand breaking and micronuclei formation as detected by a bone marrow comet assay and micronucleus test, respectively. Furthermore, using fluorescence in situ hybridization (FISH) analysis with the centromeric mouse‐satellite DNA‐probe for erythrocyte micronuclei it could be shown that citalopram is aneugen as well as clastogen in somatic cells in vivo. Colchicine (COL) and mitomycin C (MMC) were used as positive controls and these compounds produced the expected responses. Both the clastogenic and the aneugenic potential of citalopram can give rise to the development of secondary tumours and abnormal reproductive outcomes. Overall, the results suggest that citalopram at the recommended human doses induces some genetic alterations, which can adversely affect the normal cellular functioning in mice. The mechanism(s) by which citalopram cause this adverse effect appear related, in part, to primary DNA strand breakage as detected by the comet assay as well as clastogenic and aneugenic events as detected by the FISH assay. Therefore, the clinical use of citalopram must be weighed against the risks of genetic damages in citalopram users. Copyright © 2013 John Wiley & Sons, Ltd.
Microscopy of the umbilical cord of rock cavies—Kerodon rupestris Wied, 1820 (Rodenta, Caviidae)
Authors: Rodrigues Marcio Nogueira , De Oliveira Gleidson Benevides , De Paula Valéria Veras , Rodrigues Silva Alexandre , De Assis Neto Antonio Chaves , Miglino Maria Angelica , De Oliveira Moacir Franco
Published: February 2013

The rock cavies (Kerodon rupestris) are rodents belonging to family Caviidae, with habitat restricted to northeastern Brazil. Current studies have shown that blood cord has stem and hematopoietic cells both with a high regenerative potential, microscopic studies about the description in rodents and other mammals are scarce. The aim of this study was to describe the structural components of the umbilical cord of rock cavies. Rock cavies embryos at different stages of pregnancy were used, three in the first third, five in middle third, and six in the final third of gestation. They were obtained at the Centre for Wild Animals Multiplication of Federal Rural University of Semi‐Arid. In rock cavies was observed that the number of vessels involved in the transport of maternal substances was represented by two major arteries, veins and an allantois duct. The umbilical cord was delimited by amniotic epithelium, formed by a layer of squamous cells, connective tissue with characteristic of the mucosal tissue, corresponding to the Wharton jelly (fetal mesenchyme), where elastic fibers were observed and intercellular spaces were arranged in concentric blades. The morphology observed in rock cavies is similar to that described in the literature for other mammals, including man. The rock cavies are well adapted to captivity and are docile, which makes this animal an important model for study within the field of regenerative medicine. The knowledge of the umbilical cord morphology represents a base point for using this animal as a model for culture and cell therapy. Microsc. Res. Tech. 76:419–422, 2013. © 2013 Wiley Periodicals, Inc.
Evaluation of a new model of aeolian transport in the presence of vegetation
Authors: Li Junran , Okin Gregory S. , Herrick Jeffrey E. , Belnap Jayne , Miller Mark E. , Vest Kimberly , Draut Amy E.
Published: February 2013

Aeolian transport is an important characteristic of many arid and semiarid regions worldwide that affects dust emission and ecosystem processes. The purpose of this paper is to evaluate a recent model of aeolian transport in the presence of vegetation. This approach differs from previous models by accounting for how vegetation affects the distribution of shear velocity on the surface rather than merely calculating the average effect of vegetation on surface shear velocity or simply using empirical relationships. Vegetation, soil, and meteorological data at 65 field sites with measurements of horizontal aeolian flux were collected from the Western United States. Measured fluxes were tested against modeled values to evaluate model performance, to obtain a set of optimum model parameters, and to estimate the uncertainty in these parameters. The same field data were used to model horizontal aeolian flux using three other schemes. Our results show that the model can predict horizontal aeolian flux with an approximate relative error of 2.1 and that further empirical corrections can reduce the approximate relative error to 1.0. The level of error is within what would be expected given uncertainties in threshold shear velocity and wind speed at our sites. The model outperforms the alternative schemes both in terms of approximate relative error and the number of sites at which threshold shear velocity was exceeded. These results lend support to an understanding of the physics of aeolian transport in which (1) vegetation's impact on transport is dependent upon the distribution of vegetation rather than merely its average lateral cover and (2) vegetation impacts surface shear stress locally by depressing it in the immediate lee of plants rather than by changing the bulk surface's threshold shear velocity. Our results also suggest that threshold shear velocity is exceeded more than might be estimated by single measurements of threshold shear stress and roughness length commonly associated with vegetated surfaces, highlighting the variation of threshold shear velocity with space and time in real landscapes.
Analyzing decadal net ecosystem production control factors and the effects of recent climate events in Japan
Authors: Setoyama Yuko , Sasai Takahiro
Published: February 2013

To determine the mechanisms of global warming, better understand the feedback process between the atmosphere and the terrestrial ecosystem, and more fully understand the role of terrestrial ecosystem carbon cycle transitions, we must make a quantitative spatial assessment of the various, highly mutable factors that control terrestrial carbon fluxes. We quantitatively analyzed spatial and temporal net ecosystem production (NEP) factors from 2001 to 2010 at a spatial grid resolution of 1 km in Japan. After conducting six sensitivity study runs for time‐variable inputs, we calculated NEP anomaly and correlation coefficients between the default and each sensitivity study run to quantitatively examine the contribution of target inputs on NEP. The primary factor controlling the annual NEP was input related to radiation (solar radiation and albedo), and the area averaged significant correlation coefficient was 0.38, dominating 91.8% of the area. The correlation coefficient in most areas was significantly high, but in mountainous areas (>1000 m), it was low. Input related to temperature (air temperature and land surface temperature) was the second most influential factor (R2 = 0.10, area = 6.8%), and water had a significant correlation in just 28.2% of all pixels. We determined that the primary spatial and temporal NEP factors in Japan were radiation and temperature, with the dominant position gradually rotating by season among three factors. We reaffirmed the continuing importance of high spatial resolution observations to qualitatively monitor the spatial and temporal changes of the various control factors.
Forecasting net ecosystem CO2 exchange in a subalpine forest using model data assimilation combined with simulated climate and weather generation
Authors: Scott‐Denton Laura E. , Moore David J. P. , Rosenbloom Nan A. , Kittel Timothy G. F. , Burns Sean P. , Schimel David S. , Monson Russell K.
Published: February 2013

Forecasting the carbon uptake potential of terrestrial ecosystems in the face of future climate change has proven challenging. Process models, which have been increasingly used to study ecosystem‐atmosphere carbon and water exchanges when conditioned with tower‐based eddy covariance data, have the potential to inform us about biogeochemical processes in future climate regimes, but only if we can reconcile the spatial and temporal scales used for observed fluxes and projected climate. Here, we used weather generator and ecosystem process models conditioned on observed weather dynamics and carbon/water fluxes, and embedded them within climate projections from a suite of six Earth Systems Models. Using this combination of models, we studied carbon cycle processes in a subalpine forest within the context of future (2080–2099) climate regimes. The assimilation of daily averaged, observed net ecosystem CO2 exchange (NEE) and evapotranspiration (ET) into the ecosystem process model resulted in retrieval of projected NEE with a level of accuracy that was similar to that following the assimilation of half‐daily averaged observations; the assimilation of 30 min averaged fluxes or monthly averaged fluxes caused degradation in the model's capacity to accurately simulate seasonal patterns in observed NEE. Using daily averaged flux data with daily averaged weather data projected for the period 2080–2099, we predicted greater forest net CO2 uptake in response to a lengthening of the growing season. These results contradict our previous observations of reduced CO2 uptake in response to longer growing seasons in the current (1999–2008) climate regime. The difference between these analyses is due to a projected increase in the frequency of rain versus snow during warmer winters of the future. Our results demonstrate the sensitivity of modeled processes to local variation in meteorology, which is often left unresolved in traditional approaches to earth systems modeling, and the importance of maintaining similarity in the timescales used in ecosystem process models driven by downscaled climate projections.
Expression of MCP‐1 and fractalkine on endothelial cells and astrocytes may contribute to the invasion and migration of brain macrophages in ischemic rat brain lesions
Authors: Tei Nari , Tanaka Junya , Sugimoto Kana , Nishihara Tasuku , Nishioka Ryutaro , Takahashi Hisaaki , Yano Hajime , Matsumoto Shirabe , Ohue Shiro , Watanabe Hideaki , Kumon Yoshiaki , Ohnishi Takanori
Published: February 2013

Some macrophages expressing NG2 chondroitin sulfate proteoglycan (NG2) and the macrophage marker Iba1 accumulate in the ischemic core of a rat brain subjected to transient middle cerebral artery occlusion (MCAO) for 90 min. These cells are termed BINCs (for brain Iba1+/NG2+ cells) and may play a neuroprotective role. Because BINCs are bone marrow‐derived cells, they are able to invade ischemic tissue after the onset of an ischemic insult. In this study, chemokine‐based mechanisms underlying the invasion of BINCs or their progenitor cells were investigated. We found that isolated BINCs expressed mRNA encoding CCR2 and CX3CR1 at high levels. Cultured astrocytes expressed mRNA encoding their ligands, MCP‐1 and fractalkine. Recombinant MCP‐1 and/or fractalkine, as well as astrocytes, induced the migration of BINCs in vitro. mRNA for MCP‐1, fractalkine, CCR2, and CX3CR1 was expressed in the ischemic core during the acute phase of the ischemic event. Immunohistochemical studies revealed that vascular endothelial cells and astrocytic endfeet expressed MCP‐1 and fractalkine, respectively, in the ischemic core during the acute phase. CCR2+/Iba1+ monocytes attached to the inside of the vascular wall at 1 day postreperfusion (dpr), and there were CCR2+/CX3CR1+ macrophage‐like cells in the parenchyma in the ischemic lesion core at 2 dpr, which may be the progenitors for BINCs. These results suggest that CCR2+ monocytes are first attracted to the ischemic lesion by MCP‐1+ endothelial cells and migrate toward fractalkine+ astrocytic endfeet through the disrupted blood–brain barrier. Thus, chemokines may play a critical role in the accumulation of neuroprotective BINCs. © 2013 Wiley Periodicals, Inc.
Assessment of fine needle aspiration feasibility and specimen adequacy for molecular diagnostics of benign vocal fold lesions
Authors: Li Nicole Y. K. , Dailey Seth , Thibeault Susan L.
Published: February 2013

Objectives/ Hypothesis:

The use of molecular testing is becoming more significant for the diagnosis and classification of disease. The application of fine‐needle aspiration (FNA) biopsy as the means of sampling lesions in union with molecular testing could be a powerful combination in laryngology. The objectives of this study were to investigate 1) if FNA was feasible to sample benign vocal fold lesions; 2) if FNA samples provided sufficient RNA quality for molecular analysis; and 3) if gene expression of FNA samples matched paired surgical excised specimens.

Study Design:

Prospective cross‐sectional.

Methods:

Fifteen vocal fold specimens were obtained from adult patients undergoing routine surgical removal for benign vocal fold lesions using FNA and surgical excision. Comparisons were made between FNA and excision biopsies for RNA quality. Correlative analysis was completed for RNA expression of nine genes, including decorin (DCN), connective tissue growth factor (CTGF), vascular endothelial growth factor (VEGF), collagen type VI alpha 3 (COL6A3), superoxide dismutase 1 (SOD1), glutathione S‐transferase (GST2), collagen type I alpha 2 (COL1A2), ATP binding cassette (ABC), and procollagen I alpha 1 (COL1A1).

Results:

FNA and excision samples demonstrated similar RNA quality (P > 0.05). Per gene expression, four out of nine genes were moderately correlated between the paired samples (P < 0.05).

Conclusions:

FNA of the vocal fold lamina propria is technically feasible to perform. Further improvement in the FNA technology is desirable to optimize RNA quality for reliable gene expression analysis.
Prevalence of clarithromycin‐resistant Helicobacter pylori in patients with chronic tonsillitis by allele‐specific scorpion real‐time polymerase chain reaction assay
Authors: Naserpour Farivar Taghi , Najafipour Reza , Johari Pouran
Published: February 2013

Objectives/Hypothesis

To investigate the allelic prevalence of resistance to clarithromycin in the DNA of clinical isolates of Helicobacter pylori obtained from biopsy specimens of patients with chronic tonsillitis by Scorpion real‐time polymerase chain reaction (PCR).

Study Design

Pathologic specimens of patients with chronic tonsillitis were used for rapid urease test, and blocks of paraffin‐embedded tonsillar tissue were used for McMullen staining, rapid urease test, and Scorpion real‐time PCR test.

Methods

A total of 103 biopsy samples were obtained from patients with chronic tonsillitis and examined for the presence of clarithromycin resistant H. pylori. Modified McMullen staining and rapid urease test were done on the all the samples. The DNA of specimens was extracted from the pathology blocks, and Scorpion real‐time PCR was performed on a final volume of 25 μL.

Results

Of 103 biopsy specimens, 22 samples were identified as infected by H. pylori, of which none were sensitive to clarithromycin. One had the A2143G genotype, and four had the A2142G genotype. Two had a mixed sensitive and the A2143G genotype, and five had a mixed sensitive and A2142G genotype. One strain had a mixed genotype of sensitive, A2143G, and A2142G.

Conclusions

The reported rate of resistance to clarithromycin is of great variation among H. pylori strains isolated from specimens in different countries. Our study showed that the most prevalent genotypes in our H. pylori‐positive specimens was A2142G followed by A2143G, which is different from reported results of allele‐specific genotyping of H. pylori strains isolated from gastric biopsy and may be a result of cross‐resistance to erythromycin and other macrolides.
Computer‐Assisted Assessment of Ocular Synkinesis: A Comparison of Methods
Authors: Kleiss Ingrid J. , Hohman Marc H. , Quatela Olivia E. , Marres Henri A. M. , Hadlock Tessa A.
Published: February 2013

Objectives/Hypothesis:

To define an objective, easy to perform, rapid method for the assessment of ocular synkinesis by employing both the Facial Assessment by Computer Evaluation software and a modification of the Glasgow Facial Palsy Scale.

Study Design:

Retrospective study.

Methods:

Fifty normal subjects and 50 patients with known ocular synkinesis were studied. Measurements of ocular synkinesis were made using the semiautomated Facial Assessment by Computer Evaluation software, and a modification of the automated Glasgow Facial Palsy program.

Results:

The mean resting vertical palpebral fissure width of a normal eye was 10.17 mm (standard deviation [SD], 1.63 mm), and the degree of eye closure during smile was on average 21.56% (SD, 13.38%). Synkinetic eyes had a statistically significantly smaller resting palpebral fissure width on average (8.99 mm; SD, 1.61 mm; P < .001, t test), and a statistically significantly greater degree of narrowing during smiling (32.65%; SD, 13.68%; P < .001, t test). Using a modified synkinesis‐determining application of the Glasgow Facial Palsy Scale did not consistently correlate with the Facial Assessment by Computer Evaluation program or clinical observations of eye closure during smiling (R = 0.251, Pearson correlation) and puckering (R = 0.253, Pearson correlation).

Conclusions:

The Facial Assessment by Computer Evaluation program yields rapid, consistent, palpebral fissure width measurements, and when combined with a subjective self‐assessment questionnaire yields a comprehensive measure of ocular synkinesis. Our modified application of the Glasgow Facial Palsy Scale did not appear to be a reliable method for quantitative ocular synkinesis assessment.
Lifestyle and Dietary Influences on Nosebleed Severity in Hereditary Hemorrhagic Telangiectasia
Authors: Silva B. Maneesha , Hosman Anna E. , Devlin Hannah L. , Shovlin Claire L.
Published: February 2013

Objectives/Hypothesis

To identify factors influencing the severity of epistaxis in hereditary hemorrhagic telangiectasia (HHT).

Study Design

Participants with and without HHT were recruited from a specialist service and online following advertisement by the HHT Foundation International. Both groups were asked to complete a nonbiased questionnaire.

Methods

The reported effects of specific treatments or lifestyle factors on epistaxis were assigned positive values if beneficial, negative values if detrimental, or zero if “no difference” and were summed to enable statistical analysis.

Results

Epistaxis affected 649 of 666 (97%) participants with HHT and was significantly more frequent than in control participants. Specialist invasive treatments were reported as beneficial, laser therapy more frequently than cauterization. Medical treatments commonly used for HHT epistaxis (female hormones, antiestrogens, tranexamic acid, aminocaproic acid, nasal creams, and bevacizumab) also had significantly positive (beneficial) scores. Lifestyle and dietary factors were generally detrimental, but room humidification, nasal lubrication, and saline treatments were all reported as beneficial (95% confidence intervals greater than zero). Multiple food items were volunteered as being detrimental to epistaxis. The most frequently reported items were alcohol (n = 45; 6.8% of participants) and spices (n = 26, 3.9% of participants). Remaining foods reported to exacerbate epistaxis were also found to be high in salicylates (including red wine, spices, chocolate, coffee, and certain fruits), natural antiplatelet activity (garlic, ginger, ginseng, ginkgo biloba, and vitamin E15), or omega‐3 acids (oily fish, salmon).

Conclusions

This study supports existing treatments and suggests lifestyle and dietary maneuvers that may also improve nosebleeds in HHT.

Level of Evidence

2c.
Chondrosarcoma of the Subglottic Larynx
Authors: Jackson Ryan S. , Leon Marino E. , McCaffrey Thomas V.
Published: February 2013

Objectives/Hypothesis

Chondrosarcoma is a rare malignancy of the head and neck with fewer than 600 cases described in the literature. Treatment typically consists of conservation surgery with preservation of airway and preoperative voice quality. We describe five patients treated with a conservative transcervical approach utilizing the operating microscope for submucosal microdissection.

Study Design

Retrospective case series at a National Cancer Institute–designated comprehensive cancer center.

Methods

A retrospective case series from February 2004 to February 2011 was performed for all consecutive patients with laryngeal chondrosarcoma treated by the senior author with transcervical submucosal microdissection utilizing the operating microscope.

Results

Five patients with laryngeal chondrosarcoma were treated between February 2004 and February 2011. There were three male and two female patients who ranged in age from 56 to 87 years (mean, 72 years) at presentation. All five tumors were located at the level of the cricoid cartilage. Hoarseness was the most common presenting symptom (60%). Eighty percent of patients had limited vocal cord mobility. No patients required neck dissection or received radiation or chemotherapy. None of the five patients had recurrence after this approach.

Conclusions

Laryngeal chondrosarcoma is a rare tumor. Conservative surgical resection remains the mainstay of treatment. The use of an operating microscope can aid in successful resection of laryngeal chondrosarcoma while preserving laryngeal mucosa and function.

Level of Evidence

4.
Temporal bone imaging in osteogenesis imperfecta patients with hearing loss
Authors: Swinnen Freya K. R. , Casselman Jan W. , De Leenheer Els M. R. , Cremers Cor W. R. J. , Dhooge Ingeborg J. M.
Published: February 2013

Objectives/Hypothesis

Osteogenesis imperfecta (OI) is an autosomal‐dominant connective‐tissue disorder, predominantly characterized by bone fragility. Conductive hearing loss develops in half of the OI patients and often progresses to mixed loss. Findings of computed tomography (CT) and magnetic resonance (MR) imaging of the temporal bone in the largest series of OI patients to date are presented and correlated with the audiograms.

Study Design

Retrospective case series.

Methods

CT images and audiograms of 17 hearing‐impaired OI patients, aged 9 to 67 years, were analyzed retrospectively. In four patients, MR imaging was performed as well. Imaging abnormalities were correlated with type and severity of hearing loss deduced from the audiograms.

Results

CT revealed fenestral hypodense foci in the fissula ante fenestram (25 of 33 ears), oval window (23 of 33 ears), and round window (20 of 33 ears). Retrofenestral hypodensities were observed, affecting the cochlear turns (16 of 33 ears), facial nerve canal (10 of 33 ears), or semicircular canals (6 of 33 ears), or appearing like the fourth turn of the cochlea (11 of 33 ears). The site of hypodensities corresponded to the type of hearing loss in 72.2% of the OI ears. The air‐bone gap and bone‐conduction thresholds showed significant positive associations with the number of affected fenestral (P < .05) and retrofenestral structures (P < .01), respectively. Gadolinium‐enhanced MR images demonstrated active lesions in three patients with mixed hearing loss or deafness.

Conclusions

The site of hypodensities on temporal bone CT images in OI corresponds to presence and type of hearing loss determined by audiometry. The more severe the hearing loss, the more affected temporal bone structures in OI.

Level of Evidence

4. Laryngoscope, 123:1988–1995, 2013
A prospective, randomized, double‐blind study comparing the efficacy of topical anesthetics in nasal endoscopy
Authors: Gaviola Gabriel C. , Chen Viola , Chia Stanley H.
Published: February 2013

Introduction:

Transnasal endoscopy is commonly performed in an outpatient otolaryngology setting. Patients are typically administered a topical anesthetic and decongestant prior to this procedure to alleviate discomfort and improve visualization. There is no consensus on which topical anesthetic is most effective in optimizing patient experience during the procedure.

Objective:

To determine whether there is a difference in the efficacy between atomized 2% tetracaine and 4% lidocaine as a topical anesthetic prior to transnasal endoscopy.

Study Design:

Prospective, randomized, double‐blind study.

Methods:

A total of 99 patients received oxymetazoline and were randomized to receive either 2% tetracaine or 4% lidocaine prior to transnasal endoscopy. Immediately following the procedure, participants completed a survey assessing level of discomfort and other adverse symptoms pertaining to the procedure using a 10‐point visual analog scale (VAS).

Results:

There were no significant differences in VAS scores between the lidocaine and tetracaine groups. There were also no significant differences between genders in overall VAS scores and in the lidocaine and tetracaine subgroups. Older patients demonstrated significantly less discomfort or a sensation of bad taste overall. In contrast to patients receiving lidocaine, older patients receiving tetracaine experienced significantly less overall pain and discomfort, unpleasant taste, and dyspnea.

Conclusion:

In patients undergoing transnasal endoscopy, use of either 2% tetracaine or 4% lidocaine has similar effect. Tetracaine may be a better choice in older patients, however.