bluuebunny/crossref_metadata_2025 huggingface dataset:
Historical Public Health in Central Europe with Special Reference to Hungary. Long-term Environmental Effects of a Historical Cataclysm
Authors: Varga Csaba , Ember István , Murányi Edit , Kiss István
Published: February 2012

Hungary, in the centre of Carpathian basin grapples with numerous challenges in order to improve catastrophic indices of environmental conditions of the country, as well as the state of health of the population. Some of these problems are subjects of financial and health policy, and can be solved internally. The remaining environmental problems can only be remedied by cooperation with neighbouring younger countries. This vitally important cooperation is hampered by severe historical conflicts burdening even the present political affiliations. The authors give a short introduction and explanation of the recent sensitive situation in this central European region, as a late consequence of an historical cataclysm happened more than nine decades ago.
The characteristics and origins of carbonaceous aerosol at a rural site of PRD in summer of 2006
Authors: Hu W. W. , Hu M. , Deng Z. Q. , Xiao R. , Kondo Y. , Takegawa N. , Zhao Y. J. , Guo S. , Zhang Y. H.
Published: February 2012

Abstract. Both organic carbon (OC) and elemental carbon (EC) were measured during PRIDE-PRD 2006 summer campaign by using a semi-continuous thermal-optical carbon analyzer at a rural site, Back Garden (BG), which is located 50 km to the northwest of Guangzhou City. Together with the online EC/OC analyzer, various kinds of instruments related to aerosol chemical properties were employed here, which provided a good opportunity to check data quality. The concentrations of OC correlated well with the mass of organic matter (OM) and water soluble organic carbon (WSOC), implying the reliability of the data measured in this campaign. The average OC concentrations in fine particle for three typical periods during the campaign (local emission influence, typhoon and precipitation and normal days) were 28.1 μgC m−3, 4.0 μgC m−3 and 5.7 μgC m−3, respectively; and EC were 11.6 μgC m−3, 1.8 μgC m−3, and 3.3 μgC m−3, respectively. The diurnal patterns of EC and OC during the campaign were higher at night and in early morning than daytime, which was probably caused by the primary emission and accumulation in the occurrence of low boundary layer. Compared with the constant diurnal enhancement ratios of EC, the enhancement ratio of OC (OC versus (CO-CObackground)) kept in a relative high level in the afternoon, with a similar diurnal profile to oxygenated organic aerosol (OOA), due to the strong photochemical formation of OC. Here, a modified EC tracer method was used to estimate the formation of secondary organic carbon (SOC). These results showed that the average SOC concentration (normal days) at BG site was about 2.0 ± 2.3 μgC m−3, and the SOC fraction in OC could reach up to 80% with the average of 47%. The modified approach in this study proved to be effective and reliable for SOC estimation based on good correlations between estimated SOC versus OOA or WSOC, and estimated POC versus hydrocarbon-like organic aerosol (HOA).
Validation of TES methane with HIPPO aircraft observations: implications for inverse modeling of methane sources
Authors: Wecht K. J. , Jacob D. J. , Wofsy S. C. , Kort E. A. , Worden J. R. , Kulawik S. S. , Henze D. K. , Kopacz M. , Payne V. H.
Published: February 2012

Abstract. We validate satellite methane observations from the Tropospheric Emission Spectrometer (TES) with 151 aircraft vertical profiles over the Pacific from the HIAPER Pole-to-Pole Observation (HIPPO) program. We find that a collocation window of ±750 km and ±24 h does not introduce significant error in comparing TES and aircraft profiles. We validate both the TES standard product (V004) and an experimental product with two pieces of information in the vertical (V005). We determine a V004 mean bias of 65.8 ppb and random instrument error of 43.3 ppb. For V005 we determine a mean bias of 42.3 ppb and random instrument error of 26.5 ppb in the upper troposphere, and mean biases (random instrument errors) in the lower troposphere of 28.8 (28.7) and 16.9 (28.9) ppb at high and low latitudes respectively. Even when V005 cannot retrieve two pieces of information it still performs better than V004. An observation system simulation experiment (OSSE) with the GEOS-Chem chemical transport model (CTM) and its adjoint shows that TES V004 has only limited value for constraining methane sources. Our successful validation of V005 encourages its production as a standard retrieval to replace V004.
South African EUCAARI measurements: seasonal variation of trace gases and aerosol optical properties
Authors: Laakso L. , Vakkari V. , Virkkula A. , Laakso H. , Backman J. , Kulmala M. , Beukes J. P. , van Zyl P. G. , Tiitta P. , Josipovic M. , Pienaar J. J. , Chiloane K. , Gilardoni S. , Vignati E. , Wiedensohler A. , Tuch T. , Birmili W. , Piketh S. , Collett K. , Fourie G. D. , Komppula M. , Lihavainen H. , de Leeuw G. , Kerminen V.-M.
Published: February 2012

Abstract. In this paper we introduce new in situ observations of atmospheric aerosols, especially chemical composition, physical and optical properties, on the eastern brink of the heavily polluted Highveld area in South Africa. During the observation period between 11 February 2009 and 31 January 2011, the mean particle number concentration (size range 10–840 nm) was 6310 cm3 and the estimated volume of sub-10 μm particles 9.3 μm3 m−3. The aerosol absorption and scattering coefficients at 637 nm were 8.3 Mm−1 and 49.5 Mm−1, respectively. The mean single-scattering albedo at 637 nm was 0.84 and the Ångström exponent of scattering was 1.5 over the wavelength range 450–635 nm. The mean O3, SO2, NOx and H2S-concentrations were 37.1, 11.5, 15.1 and 3.2 ppb, respectively. The observed range of concentrations was large and attributed to the seasonal variation of sources and regional meteorological effects, especially the anticyclonic re-circulation and strong winter-time inversions. In a global context, the levels of gases and particulates were typical for continental sites with strong anthropogenic influence, but clearly lower than the most polluted areas of south-eastern Asia. Of all pollutants observed at the site, ozone is the most likely to have adverse environmental effects, as the concentrations were high also during the growing season. The measurements presented here will help to close existing gaps in the ground-based global atmosphere observation system, since very little long-term data of this nature is available for southern Africa.
Temporal trend and sources of speciated atmospheric mercury at Waliguan GAW station, Northwestern China
Authors: Fu X. W. , Feng X. , Liang P. ,   Deliger, Zhang H. , Ji J. , Liu P.
Published: February 2012

Abstract. Measurements of speciated atmospheric mercury were conducted at a remote mountain-top station (Waliguan (WLG) Baseline Observatory) at the edge of northeastern part of the Qinghai-Xizang Plateau, Western China. Mean concentrations of total gaseous mercury (TGM), particulate bound mercury (PBM), and gaseous oxidized mercury (GOM) during the whole sampling campaign were 1.98±0.98 ng m−3, 19.4±18.1 pg m−3, and 7.4±4.8 pg m−3, respectively. Levels of speciated Hg at WLG were slightly higher than those reported from remote areas of North America and Europe. Both regional sources and long-rang transport played important roles in the distribution of atmospheric TGM and PBM at WLG, whereas GOM showed major links to the regional sources, likely as well as the in-situ productions via photochemical processes. Regional sources for speciated Hg were mostly located to the east of WLG, which is the most industrial and urbanized areas of Qinghai province. Potential source contribution function (PSCF) results showed that eastern Gansu, western Ningxia and Shanxi Province were likely the potential source regions of WLG, with good accordance with locations of urban areas and industrial centers. Moreover, we found that Northern India may be a significant source region for WLG during the sampling campaign, and this is the first published evidence suggesting long-range transport of atmospheric Hg from India to the Northeastern Tibetan Plateau. Seasonal and diurnal variations of TGM were in contrast to most of the previous studies in China, with relatively higher levels in warm seasons and night, respectively. The temporal trend of TGM also highlighted the impact of long-range transport on the distribution of TGM in ambient air at WLG.
Analysis of co-located MODIS and CALIPSO observations near clouds
Authors: Várnai T. , Marshak A.
Published: February 2012

Abstract. This paper aims at helping synergistic studies in combining data from different satellites for gaining new insights into two critical yet poorly understood aspects of anthropogenic climate change, aerosol-cloud interactions and aerosol radiative effects. In particular, the paper examines the way cloud information from the MODIS (MODerate resolution Imaging Spectroradiometer) imager can refine our perceptions based on CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) lidar measurements about the systematic aerosol changes that occur near clouds. The statistical analysis of a yearlong dataset of co-located global maritime observations from the Aqua and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellites reveals that MODIS's multispectral imaging ability can greatly help the interpretation of CALIOP observations. The results show that imagers on Aqua and CALIPSO yield very similar pictures, and that the discrepancies – due mainly to wind drift and differences in view angle – do not significantly hinder aerosol measurements near clouds. By detecting clouds outside the CALIOP track, MODIS reveals that clouds are usually closer to clear areas than CALIOP data alone would suggest. The paper finds statistical relationships between the distances to clouds in MODIS and CALIOP data, and proposes a rescaling approach to statistically account for the impact of clouds outside the CALIOP track even when MODIS cannot reliably detect low clouds, for example at night or over sea ice. Finally, the results show that the typical distance to clouds depends on both cloud coverage and cloud type, and accordingly varies with location and season. In maritime areas perceived cloud free, the global median distance to clouds below 3 km altitude is in the 4–5 km range.
Profiles of CH4, HDO, H2O, and N2O with improved lower tropospheric vertical resolution from Aura TES radiances
Authors: Worden J. , Kulawik S. , Frankenberg C. , Payne V. , Bowman K. , Cady-Peirara K. , Wecht K. , Lee J.-E. , Noone D.
Published: February 2012

Abstract. Thermal infrared (IR) radiances measured near 8 microns contain information about the vertical distribution of water vapor (H2O), the water isotopologue HDO, and methane (CH4), key gases in the water and carbon cycles. Previous versions (Version 4 or less) of the TES profile retrieval algorithm used a "spectral-window" approach to minimize uncertainty from interfering species at the expense of reduced vertical resolution and sensitivity. In this manuscript we document changes to the vertical resolution and uncertainties of the TES version 5 retrieval algorithm. In this version (Version 5), joint estimates of H2O, HDO, CH4 and nitrous oxide (N2O) are made using radiances from almost the entire spectral region between 1100 cm−1 and 1330 cm−1. The TES retrieval constraints are also modified in order to better use this information. The new H2O estimates show improved vertical resolution in the lower troposphere and boundary layer, while the new HDO/H2O estimates can now profile the HDO/H2O ratio between 925 hPa and 450 hPa in the tropics and during summertime at high latitudes. The new retrievals are now sensitive to methane in the free troposphere between 800 and 150 mb with peak sensitivity near 500 hPa; whereas in previous versions the sensitivity peaked at 200 hPa. However, the upper troposphere methane concentrations are biased high relative to the lower troposphere by approximately 4% on average. This bias is likely related to temperature, calibration, and/or methane spectroscopy errors. This bias can be mitigated by normalizing the CH4 estimate by the ratio of the N2O estimate relative to the N2O prior, under the assumption that the same systematic error affects both the N2O and CH4 estimates. We demonstrate that applying this ratio theoretically reduces the CH4 estimate for non-retrieved parameters that jointly affect both the N2O and CH4 estimates. The relative upper troposphere to lower troposphere bias is approximately 2.8% after this bias correction. Quality flags based upon the vertical variability of the methane and N2O estimates can be used to reduce this bias further. While these new CH4, HDO/H2O, and H2O estimates are consistent with previous TES retrievals in the altitude regions where the sensitivities overlap, future comparisons with independent profile measurement will be required to characterize the biases of these new retrievals and determine if the calculated uncertainties using the new constraints are consistent with actual uncertainties.
Technical Note: Calibration instrument for the krypton hygrometer KH20
Authors: Foken T. , Falke H.
Published: February 2012

Abstract. A calibration instrument for krypton hygrometers (KH20, Campbell Sci.) with variable path length is presented. This unit allows for in-situ calibrations of the krypton hygrometer, which is typically not very stable over time, during measuring campaigns. It was constructed mainly for application at high altitudes and low temperatures, where further improvements are needed to the IR-hygrometers which are normally used. The changing path length requires that a changing concentration of the absorber be simulated. Because oxygen absorbs more strongly than water vapour, the calibration is made against oxygen and transferred to water vapour. The design of the calibration instrument is made as one unit containing a stepper motor system, PC and humidity sensor. For the calibration, it is necessary to install the krypton hygrometer on this unit.
Observations of tropical rain with a polarimetric X-band radar: first results from the CHUVA campaign
Authors: Schneebeli M. , Sakuragi J. , Biscaro T. , Angelis C. F. , Carvalho da Costa I. , Morales C. , Baldini L. , Machado L. A. T.
Published: February 2012

Abstract. A polarimetric X-band radar has been deployed during one month (April 2011) for a field campaign in Fortaleza, Brazil, together with additional sensors like a Ka-band vertically pointing frequency modulated continuous wave (FMCW) radar and three laser disdrometers. The disdrometers as well as the FMCW radar are capable of measuring the rain drop size distributions (DSDs), hence making it possible to forward-model theoretical polarimetric X-band radar observables at the point where the instruments are located. This set-up allows to thoroughly test the accuracy of the X-band radar measurements as well as the algorithms that are used to correct the radar data for radome and rain attenuation. In the first campaign in Fortaleza it was found that radome attenuation dominantly affects the measurements. With an algorithm that is based on the self-consistency of the polarimetric observables, the radome induced reflectivity offset was estimated. Offset corrected measurements were then further corrected for rain attenuation with two different schemes. The performance of the post-processing steps is being analyzed by comparing the data with disdrometer-inferred polarimetric variables that were measured in a distance of 20 km to the radar.
Rapid coupling of Antarctic temperature and atmospheric CO2 during deglaciation
Authors: Pedro J. B. , Rasmussen S. O. , van Ommen T. D.
Published: February 2012

Abstract. Antarctic ice cores provide clear evidence of a close coupling between variations in Antarctic temperature and the atmospheric concentration of CO2 during the glacial/interglacial cycles of the past 800 thousand years. Precise information on the relative timing of the temperature and CO2 changes can assist in refining our understanding of the physical processes involved in this coupling. Here, we focus on the last deglaciation, 19 000 to 11 000 years before present, during which CO2 concentrations increased by ~80 parts per million by volume and Antarctic temperature increased by ~10 °C. Utilising a recently developed proxy for regional Antarctic temperature, derived from five near-coastal ice cores, and two ice core CO2 records with high dating precision, we show that the increase in CO2 lagged the increase in regional Antarctic temperature by only 0–400 years. This new value for the lag, consistent for both CO2 records, implies a faster feedback between temperature and CO2 than the centennial to millennial-scale lags suggested by previous studies.
Downscaling the climate change for oceans around Australia
Authors: Chamberlain M. A. , Sun C. , Matear R. J. , Feng M. , Phipps S. J.
Published: February 2012

Abstract. At present, global climate models used to project changes in climate do not resolve mesoscale ocean features such as boundary currents and eddies. These missing features may be important to realistically project the marine impacts of climate change. Here we present a framework for dynamically downscaling coarse climate change projections utilising a global ocean model that resolves these features in the Australian region. The downscaling model used here is ocean-only. The ocean feedback on the air-sea fluxes is explored by restoring to surface temperature and salinity, as well as a calculated feedback to wind stress. These feedback approximations do not replace the need for fully coupled models, but they allow us to assess the sensitivity of the ocean in downscaled climate change simulations. Significant differences are found in sea surface temperature, salinity, stratification and transport between the downscaled projections and those of the climate model. While the magnitude of the climate change differences may vary with the feedback parameterisation used, the patterns of the climate change differences are consistent and develop rapidly indicating they are mostly independent of feedback that ocean differences may have on the air-sea fluxes. Until such a time when it is feasible to regularly run a global climate model with eddy resolution, our framework for ocean climate change downscaling provides an attractive way to explore how climate change may affect the mesoscale ocean environment.
MAESPA: a model to study interactions between water limitation, environmental drivers and vegetation function at tree and stand levels, with an example application to [CO2] × drought interactions
Authors: Duursma R. A. , Medlyn B.E.
Published: February 2012

Abstract. Process-based models (PBMs) of vegetation function can be used to interpret and integrate experimental results. Water limitation to plant carbon uptake is a highly uncertain process in the context of environmental change, and many experiments have been carried out that study drought limitations to vegetation function at spatial scales from seedlings to entire canopies. What is lacking in the synthesis of these experiments is a quantitative tool that can be used to integrate and analyse experimental results at scales of both the whole-plant and the forest canopy, and that includes a detailed mechanistic representation of the water balance. To fill this gap, we developed an individual tree-based model (MAESPA), largely based on combining the well-known MAESTRA and SPA ecosystem models. The model includes a hydraulically-based model of stomatal conductance, root water uptake routines, drainage, infiltration, runoff and canopy interception, as well as detailed radiation interception and leaf physiology routines from the MAESTRA model. The model can be applied both to single plants of arbitrary size and shape, as well as stands of trees. The utility of this model is demonstrated by studying the interaction between elevated [CO2] (eCa) and drought. Based on theory, this interaction is generally expected to be positive, so that plants growing in eCa should be less susceptible to drought. Experimental results, however, are varied. We apply the model to a previously published experiment on droughted cherry, and show that changes in plant parameters due to long-term growth at eCa (acclimation) may strongly affect the outcome of Ca × drought experiments. We discuss potential applications of MAESPA and some of the key uncertainties in process representation.
Modelling the mid-Pliocene Warm Period climate with the IPSL coupled model and its atmospheric component LMDZ4
Authors: Contoux C. , Ramstein G. , Jost A.
Published: February 2012

Abstract. This paper describes the experimental design and model results of the climate simulations of the mid-Pliocene Warm Period (mPWP, ca. 3.3–3 Ma) using the Institut Pierre Simon Laplace model (IPSLCM5A), in the framework of the Pliocene Model Intercomparison Project (PlioMIP). We use the IPSL atmosphere ocean general circulation model (AOGCM), and its atmospheric component alone, to simulate the climate of the mPWP. Boundary conditions such as sea surface temperatures (SSTs), topography, ice sheet extent and vegetation are derived from the ones imposed by the Pliocene Model Intercomparison Project (PlioMIP), described in Haywood et al. (2010, 2011). We first describe the IPSL model main features, and then give a full description of the boundary conditions used for atmospheric model and coupled model experiments. The climatic outputs of the mPWP simulations are detailed and compared to the corresponding control simulations. The simulated warming is 1.94 °C in the atmospheric and 1.83 °C in the coupled model experiments. In both experiments, warming is more important at high latitudes. Simulated precipitation has a different behaviour in the coupled model than in the atmospheric model alone, because of the reduced gradients in imposed SSTs, which impacts the Hadley and Walker circulations. In addition, a sensitivity test to the change of land-sea mask in the atmospheric model, representing a sea-level change from present-day to 25 m higher during the mid-Pliocene, is described. We find that surface temperature differences can be important (several degrees Celsius) but are restricted to the areas that were changed from ocean to land or vice versa. In terms of precipitation, there is no impact on polar regions although the change in land-sea mask is important in these areas.
Development of an operational coastal flooding early warning system
Authors: Doong D.-J. , Chuang L. Z.-H. , Wu L.-C. , Fan Y.-M. , Kao C. C. , Wang J.-H.
Published: February 2012

Abstract. Coastal floods are a consistent threat to oceanfront countries, causing major human suffering and substantial economic losses. Climate change is exacerbating the problem. An early warning system is essential to mitigate the loss of life and property from coastal flooding. The purpose of this study is to develop a coastal flooding early warning system (CoFEWs) by integrating existing sea-state monitoring technology, numerical ocean forecasting models, historical database and experiences, as well as computer science. The proposed system has capability of offering data for the past, information for the present and future. The system was developed for the Taiwanese coast due to its frequent threat by typhoons. An operational system without any manual work is the basic requirement of the system. Integration of various data sources is the system kernel. Numerical ocean models play an important role within the system because they provide data for assessment of possible flooding. The regional wave model (SWAN) that nested with the large domain wave model (NWW III) is operationally set up for coastal wave forecasting, in addition to the storm surge predicted by a POM model. Data assimilation technology is incorporated for enhanced accuracy. A warning signal is presented when the storm water level that accumulated from astronomical tide, storm surge, and wave-induced run-up exceeds the alarm sea level. This warning system has been in practical use for coastal flooding damage mitigation in Taiwan for years. An example of the system operation during the Typhoon Haitung which struck Taiwan in 2005 is illustrated in this study.
A radiological study of some ornamental stones: the bluish granites from Extremadura (Spain)
Authors: Pereira D. , Neves L. , Pereira A. , Peinado M. , Blanco J. A. , Tejado J. J.
Published: February 2012

Abstract. In the area of Trujillo (Extremadura, Spain) we have found a variety of striking bluish and secondary yellow granites outcropping within the Plasenzuela pluton. They are all quarried under different names and are characterized by leucocratic minerals in which a bluish phosphate is dispersed throughout the rock. Their physical and mechanical properties make these granites a perfect option for most applications as ornamental rocks. Within the pluton the radiological background is fairly homogeneous, with no significant differences between the gamma ray fluxes of the different facies. U (6.4 ± 0.51 ppm), Th (2.9 ± 0.47 ppm) and K2O (4.32 ± 0.26%) contents determined in the laboratory by gamma-ray spectrometry from representative samples are in good accordance with fast in situ measurements carried out with the same technique and also with conventional chemical analysis. Estimated activities for K-40, Ra-226 and Th-232 were, on average, 1022 ± 36 Bq kg−1, 84 ± 9 Bq kg−1 and 6.8 ± 1.6 Bq kg−1. On the basis of these results, the I index of EU technical document 112 was determined, with an average result of 0.66 ± 0.03. This suggests that the rock can be used with no restrictions for all types of construction purposes. Striking differences were observed between the blue facies and the yellow facies in radon exhalation tests from crushed material (0.03 Bq kg−1 vs. 0.20 Bq kg−1). Since both granites have similar uranium contents (6.3 ppm and 6.5 ppm, respectively), these results can probably be explained in terms of important differences in the mineralogical distribution of this chemical element, radon emanation being enhanced in the yellow facies. However, due to the ordinary use as ornamental stone, the yellow facies does not present a radiological risk in terms of excess effective dose due to internal exposure to radon.
Modelling temperature and salinity in Liverpool Bay and the Irish Sea: sensitivity to model type and surface forcing
Authors: O'Neill C. K. , Polton J. A. , Holt J. T. , O'Dea E. J.
Published: February 2012

Abstract. Three shelf sea models are compared against observed surface temperature and salinity in Liverpool Bay and the Irish Sea: a 7 km NEMO model, and 12 km and 1.8 km POLCOMS models. Each model is run with two different surface forcing datasets of different resolutions. Comparisons with a variety of observations from the Liverpool Bay Coastal Observatory show that increasing the surface forcing resolution improves the modelled surface temperature in all the models, in particular reducing the summer warm bias and winter cool bias. The response of surface salinity is more varied with improvements in some areas and deterioration in others. The 7 km NEMO model performs as well as the 1.8 km POLCOMS model when measured by overall skill scores although the sources of error in the models are different. NEMO is too weakly stratified in Liverpool Bay, whereas POLCOMS is too strongly stratified. The horizontal salinity gradient, which is too strong in POLCOMS, is better reproduced by NEMO which uses a more diffusive horizontal advection scheme. This leads to improved semi-diurnal variability in salinity in NEMO at a mooring site located in the Liverpool Bay ROFI area.
Changes in the marine-terminating glaciers of central east Greenland, 2000–2010
Authors: Walsh K. M. , Howat I. M. , Ahn Y. , Enderlin E. M.
Published: February 2012

Abstract. Marine-terminating outlet glaciers of the Greenland Ice Sheet have undergone substantial changes over the past decade. The synchronicity of these changes suggest a regional external forcing, such as changes in coastal ocean heat transport and/or increased surface melt and subglacial runoff. A distinct contrast in rates of ice front retreat has been observed between glaciers north and south of 69° N latitude on along the East Greenland coast. This latitude corresponds with the northward limit of subtropical waters carried by the Irminger Current, suggesting variability in ocean heat transport as the dominant forcing. Glacier surging, however, is yet another mechanism of change in this region. In order to provide further spatial and temporal constraint on glacier change across this important oceanographic transition zone, we construct time series of thinning, retreat and flow speed of 37 marine-terminating glaciers along the central east Greenland coast from 2000 to 2010. We assess this dataset for spatial and temporal patterns that may elucidate the mechanisms of glacier change. We confirm that glacial retreat, dynamical thinning, and acceleration have been more pronounced south of 69° N, with a high degree of variability along the Blosseville Coast and little inter-annual change in Scoresby Sound. Our results support the conclusion that variability in coastal ocean heat transport is the primary driver of regional glacier change, but that local factors, such as surging and/or individual glacier morphology, are overprinted on this regional signal.
Significant total mass contained in small glaciers
Authors: Bahr D. B. , Radić V.
Published: February 2012

Abstract. A single large glacier can contain hundreds of millions of times the mass of a small glacier. Nevertheless, small glaciers are so numerous that their contribution to the world's total ice volume is significant and may be a notable source of error if excluded. With current glacier inventories, total volume errors on the order of 10 % are possible at both global and regional scales. However, errors of less than 1 % require glaciers that are smaller than those available in some inventories. Such accuracy requires a global list of all glaciers and ice caps (GIC) as small as 1 km2, and for regional estimates requires substantially smaller sizes. For some regions, volume errors of less than 5 % require a complete list of all glaciers down to the smallest conceivable sizes. For this reason, sea-level rise estimates and other total mass and total volume analyses cannot ignore the world's smallest glaciers without careful justification.
Autologous conjunctival epithelium transplantation and scleral patch graft for postlensectomy wound leakage in Marfan syndrome
Authors: Mancino Raffaele , Aiello Francesco , Ceccarelli Simona , Marchese Cinzia , Varesi Chiara , Nucci Carlo , Cerulli Luciano
Published: February 2012

Purpose

We report a case of woman with Marfan syndrome and longstanding postlensectomy scleral wound dehiscence.

Methods

A 34-year-old woman with Marfan syndrome who underwent lensectomy 20 years ago had conjunctival leakage with chronic hypotony and conjunctival cystic degeneration secondary to scleral wound dehiscence. Presentation, clinical evaluation, and particular treatment with autologous cultivated conjunctival epithelium transplantation and scleral patch graft are described.

Results

A 6-month follow-up confirmed complete epithelization of the ocular surface and absence of leaking from the wound with normal intraocular pressure.

Conclusions

Transplantation of autologous cultivated conjunctival epithelium appears to be a valid strategy in the treatment of ocular disease requiring extensive excision of the conjunctiva.
Tracing the Links between Absorptive Capacity, University Knowledge Exchange and Competitive Advantage in SMEs
Authors: Fogg Helen
Published: February 2012

Can university knowledge exchange give small businesses the ability to gain competitive advantage? The main purpose of this study is, first, to understand the limitations for small firms in absorbing knowledge from higher education institutions and, second, to ascertain whether access to knowledge resources, such as a university, can be an antecedent factor for building absorptive capacity in small and medium-sized enterprises (SMEs) and creating business value. The paper is a conceptual study in which a model for knowledge exchange between a management school and SMEs is proposed. The model was developed, drawing on the literature and prior SME knowledge exchange expertise of the management school, to deliver a three-year project funded by the European Regional Development Fund. The project, ‘Innovation for Growth’, is designed to embed innovation in the business processes and practices of 300 SMEs in the north-west of England. This paper offers recommendations for improving policy aimed at supporting the innovation process of small firms; a proposed model of knowledge exchange between university and small firms; and a strategy for small businesses to improve their absorptive capacity.
Teaching Old Dogs New Tricks: Why Unlearning Matters in SMEs
Authors: McKeown Ian
Published: February 2012

Developing a better understanding of how small firms release redundant knowledge, beliefs and practices is becoming increasingly important in environments characterized by discontinuity. This explorative research focuses on unlearning as a means of accomplishing this task. The self-reinforcing and enduring nature of existing knowledge, practice and situated power is recognized. Unlearning requires a sustained disruptive discourse to challenge the embedded assumptions of the firm. A significant finding of the research is that this discourse is often beyond the capability of the firm itself. The intervention of external actors is therefore required to create the necessary reflective space and legitimacy to reframe knowledge and beliefs.
Propagation of goldenrod (Solidago canadensis L.) from leaf and nodal explants
Authors: Li Jun , Kang Ye , Qiang Sheng , Peng Gary
Published: February 2012

Goldenrod (Solidago canadensis L.) is an invasive plant species in many countries except North America but a cut-flower species worldwide. There is a need to generate and propagate goldenrod clones efficiently for research and commercial purposes. A callus induction and plantlet regeneration system was developed by studying the influence of explant type and different concentrations of plant growth regulators. The highest callus production from leaf segments was obtained on Murashige and Skoog’s medium (MS medium) supplemented with 1.0 mg/L naphthalene acetic acid (NAA) and 1.0 mg/L 6-benzylaminopurine (BA). Adventitious shoots could be regenerated directly from leaf explants without an intermediate callus phase with the highest shoot induction percentage of 87.2%. The largest number of adventitious shoots per leaf explant (3.2) was obtained on MS medium supplemented with 0.4 mg/L NAA and 2.0 mg/L BA. MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L BA was the best medium for axillary shoot regeneration from nodal segments. The highest root number and longest roots occurred on half-strength MS without the addition of any growth regulator. Rooted plantlets were then transferred to a soil-based growth medium, placed in a greenhouse, and acclimatized with 100% success. All surviving plants grew normally without showing any morphological varia­tion when compared to those grow from seed. This regeneration protocol may be used to produce certain biotypes of goldenrod suitable for genetic transformation rapid propagation of goldenrod for commercial purposes or for screening fungi and toxins as potential biocontrol agents against this weed.
Polyrotaxanes
Authors: Harada Akira , Hashidzume Akihito , Yamaguchi Hiroyasu , Takashima Yoshinori
Published: February 2012

A large number of examples of polyrotaxanes have been reported. These examples include various macrocycles, for example, crown ethers, cyclophanes, calyx[n]arenas, cyclodextrins (CDs), cucurbiturils, cyclobis(paraquat‐p‐phenylene), and pillararenes, and numerous types of axes depending on the macrocycles. Polyrotaxanes are categorized into two classes based on their structure: main‐chain polyrotaxanes and side‐chain polyrotaxanes. In the former, macrocyles include the polymer main chain, whereas side chains in the latter. This review shows typical examples of main‐chain and side‐chain polyrotaxanes, mainly focusing on CDs.
Fluorescence of Colloidal Gold Nanoparticles is Controlled by the Surface Adsorbate
Authors: Goldys Ewa M. , Sobhan Mushtaq A.
Published: February 2012

Fluorescent gold nanoparticles are important biological labels, in particular for combined optical and electron microscopy. It is reported that density and type of surface ligands have key influence on the dominant UV‐vis fluorescence band in positively and negatively charged gold nanoparticles capped with citrate, gold oxide, and cetyltrimethyl ammonium bromide (CTAB). The peak excitation and emission energies and fluorescence intensities vary with nanoparticle size, reflecting changes in surface charge and surface potential as well as a varying density of surface adsorbates. The fluorescence peak shifts, the evolution of zeta potentials, and fluorescence intensity trends are explained by a model of the principal fluorescence transitions that takes into account the nanoparticle surface conditions, such as the adhesion of ligands. Varying surface ligands is a simple strategy to optimize fluorescence intensity and to design spectral properties of gold nanoparticles.
High Energy Density Supercapacitor Based on a Hybrid Carbon Nanotube–Reduced Graphite Oxide Architecture
Authors: Jha Neetu , Ramesh Palanisamy , Bekyarova Elena , Itkis Mikhail E. , Haddon Robert C.
Published: February 2012

A high energy density supercapacitor device is reported that utilizes hybrid carbon electrodes and the ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4) as an electrolyte. The hybrid electrodes are prepared from reduced graphite oxide (rGO) and purified single‐walled carbon nanotubes (SWCNTs). A simple casting technique gives the hybrid structure with optimum porosity and functionality that provides high energy and power densities. The combination of SWCNTs and rGO in a weight ratio of 1:1 is found to afford a specific capacitance of 222 F g−1 and an energy density of 94 Wh kg−1 at room temperature.
Association of X‐linked hydrocephalus and Hirschsprung disease: Report of a new patient with a mutation in the L1CAM gene
Authors: Fernández Raquel M. , Núñez‐Torres Rocío , García‐Díaz Lutgardo , de Agustín Juan Carlos , Antiñolo Guillermo , Borrego Salud
Published: February 2012

X‐linked hydrocephalus (XLH) has an incidence of 1/30,000 male births and is characterized by intellectual disability, spastic paraplegia, adducted thumbs, and agenesis of corpus callosum, and/or corticospinal tract. The great proportion of cases is ascribed to loss of function mutations of L1CAM gene. Hirschsprung disease (HSCR) is characterized by the absence of ganglion cells in the submucosal and myenteric plexuses along a variable portion of the intestinal tract and has incidence of about 1/5,000. Although with several genes involved in its pathogenesis, the major HSCR gene is the RET proto‐oncogene. To date only a few patients have been reported with both phenotypes and mutations in the L1CAM gene. In this report, we describe a new patient with concurrent XLH and HSCR. L1CAM mutational screening showed the presence of the G698R hemizygous mutation, which is a deleterious substitution affecting a key residue necessary for the correct folding of the protein. Moreover, the patient also carried the transcriptional enhancer RET mutation (c.73 + 9277T > C) in heterozygosis. We speculate that both the RET enhancer variant, and the L1CAM mutation may act in combination to produce the enteric phenotype, probably with the participation of other still unidentified molecular events. While it is obvious that additional studies are necessary to further delineate the association between XLH and HSCR in the presence of L1CAM mutations, the documentation of this new patient reinforces the role of this gene acting either in a direct or indirect way in the pathogenesis of Hirschsprung disease. © 2012 Wiley Periodicals, Inc.
Preparation and properties of the highly porous poly(ethylene‐co‐vinyl alcohol)/multiwalled carbon nanotube nanocomposites prepared by a simple saponification method
Authors: Lee Eun‐Ju , Yoon Jin‐San , Park Eun‐Soo
Published: February 2012

Multiwalled carbon nanotubes (MWNTs) were functionalized by electron‐beam (EB) irradiation in air at room temperature. As the EB dose was increased to 1000 kGy, Fourier transform infrared analysis detected the formation of carbonyl groups in the irradiated MWNTs. Poly(ethylene‐co‐vinyl alcohol)/MWNT nanocomposite particles were prepared by the incorporation of EB‐irradiated MWNTs in a poly(ethylene‐co‐vinyl acetate) (EVA)/toluene solution and saponification in an ethanol/KOH solution. Scanning electron microscopy observation showed that the nanocomposite particles had a highly porous, spongelike structure of connected matrix polymers and MWNTs. At low EVA/MWNT concentrations, the particles were less porous, and the precipitated polymer phase had a granular structure. At high concentrations, the porosity increased, and the precipitated polymer phase became spongelike. The thermal and mechanical properties and the electrical resistivity change of the prepared nanocomposites were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Exfoliated/intercalated silicate/hot styrene butadiene rubber nanocomposites: Structure–properties relationship
Authors: Díez J. , Barral L. , Bellas R. , López J. , Ramírez C. , Rodríguez A.
Published: February 2012

Rubber nanocomposites based on hot styrene‐butadiene rubber (SBR) and organophilic layered silicate were prepared via mechanical mixing followed by compression molding. Varying amount of organically modified nanosilicate, 2.5, 5, 10, and 15 parts per hundred of rubber (phr), was added to the SBR matrix to examine the influence of nanosilicate on morphology and structure–property relationships. The morphology of nanocomposites was studied by X‐ray diffraction and transmission electron microscopy which reveal that the nanocomposite contained a good dispersion of intercalated/exfoliated layers through the matrix. The interaction between SBR matrix and nanofiller was studied by infrared spectroscopy. No clear evidence for the formation of new components in the rubber was found but infrared spectroscopy denoted evidence for exfoliation. The reinforcing effect of the nanosilicate was determined by mechanical testing and dynamomechanical analysis. The results indicate that the tensile properties and the storage modulus increased with increasing nanofiller loading. This suggests a strong rubber–nanosilicate interaction which is attributed to the exfoliated/intercalated structure. Thermogravimetric analysis revealed that incorporation of organoclay enhances the thermal stability of the nanocomposites. The best thermal stability was observed for nanocomposites containing 5 phr nanosilicate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Hadrosaurs Were Perennial Polar Residents
Authors: Chinsamy Anusuya , Thomas Daniel B. , Tumarkin‐Deratzian Allison R. , Fiorillo Anthony R.
Published: February 2012

Recent biomechanical evidence has fuelled debate surrounding the winter habits of the hadrosaurian dinosaur Edmontosaurus (ca. 70 Ma). Using histological characteristics recorded in bone, we show that polar Edmontosaurus endured the long winter night. In contrast, the bone microstructure of temperate Edmontosaurus is inconsistent with a perennially harsh environment. Differences in the bone microstructure of polar and temperate Edmontosaurus consequently dispute the hypothesis that polar populations were migratory. The overwintering signal preserved in the microstructure of polar Edmontosaurus bone offers significant insight into the life history of dinosaurs within the Late Cretaceous Arctic. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Increased expression of the integral membrane proteins EGFR and FGFR3 in anti‐apoptotic Chinese hamster ovary cell lines
Authors: Ohsfeldt Erika , Huang Szu‐Han , Baycin‐Hizal Deniz , Kristoffersen Linda , Le Thuy‐My T. , Li Edwin , Hristova Kalina , Betenbaugh Michael J.
Published: February 2012

Membrane proteins such as receptor tyrosine kinases (RTKs) have a vital role in many cellular functions, making them potential targets for therapeutic research. In this study, we investigated the coexpression of the anti‐apoptosis gene Bcl‐xL with model membrane proteins as a means of increasing membrane protein expression in mammalian cells. Chinese hamster ovary (CHO) cells expressing heterologous Bcl‐xL and wild‐type CHO cells were transfected with either epidermal growth factor receptor or fibroblast growth factor receptor 3. The CHO–Bcl‐xL cell lines showed increased expression of both RTK proteins as compared with the wild‐type CHO cell lines in transient expression analysis, as detected by Western blot and flow cytometry after 15 days of antibiotic selection in stable expression pools. Increased expression was also seen in clonal isolates from the CHO–Bcl‐xL cell lines, whereas the clonal cell line expression was minimal in wild‐type CHO cell lines. Our results demonstrate that application of the anti‐apoptosis gene Bcl‐xL can increase expression of RTK proteins in CHO cells. This approach may be applied to improve stable expression of other membrane proteins in the future using mammalian cell lines with Bcl‐xL or perhaps other anti‐apoptotic genes.
Watching grass grow in Australia: is there sufficient production potential for a biofuel industry?
Authors: Herr Alexander , O'Connell Deborah , Farine Damien , Dunlop Michael , Crimp Steven , Poole Michael
Published: February 2012

Grasses could provide an alternative to the use of food crops for biofuel production. Australia has large areas of non‐crop land that already produce grasses. However, there is currently no detailed assessment of Australia's grass production potential for bioenergy or carbon management. This paper provides an overview of grass production potential in Australia. Our approach is based on modeling native grass pastures net primary production (NPP) at a broad scale using the AussieGRASS NPP model. We assess the technical production potential of grasses for the whole of Australia; and, after excluding unsuitable production areas examine the bioenergy feedstock potential in seven regions around Australia. The paper identifies areas for grass feedstock production outside existing cropping and hay production areas. The analysis highlights areas of high production in north‐east Australia around the Tropic of Capricorn. The non‐cleared land in this extensive agricultural zone shows a promising technical production potential (266 Mt y−1) and if 15% of this land's NPP were to be transformed into ethanol, it could replace a significant part (54%) of current Australian petrol demand. We subsequently discuss these modeling results to identify areas for further improvement and future development for this approach that would produce a more robust spatial grass feedstock assessment. The paper investigates only a set of technical constraints for grass production. There will be many other constraints to consider, e.g. competing uses for grass resources from crop and animal production, and conservation needs, which will reduce the possible off‐take of grasses for energy. © 2012 Commonwealth of Australia