bluuebunny/crossref_metadata_2025 huggingface dataset:
Facebook and the Societal Aspects of Formal Learning
Authors: Woodley Carolyn , Dorrington Petrina
Published: November 2013

An online subject used social media to provide “collaborative spaces” that were “additional and complementary” to discussion in the university’s Learning Management System (LMS). Facebook and Twitter provided optional “informal spaces” in which students “talk about general issues to do with media and connect with other students in the unit.” This chapter’s analysis of Facebook posts shows a cooperative group of peers providing advice on assessment and recommending useful resources. Analysis, however, reveals that, as well as supportive posts, a proportion of posts could be considered inappropriate, distracting, or even, infrequently, inflammatory. Guidelines about acceptable behaviour must be imposed by teaching staff. More importantly, optional participation in social media sites requires critical consideration. If Facebook is used as a student support space for an online subject, it should be integrated into the curriculum and have an explicit purpose; making social media sites optional alongside mandatory university-supported platforms can prove problematic.
Diigo, Collaborative Knowledge Acquisition, and Social Networks of Graduate-Level Coursework
Authors: Fenn John
Published: November 2013

This chapter offers description and reflexive insight into the multiple ways the authors has used Diigo as a collaborative learning tool in courses associated with the Master's of Arts Management degree program at the University of Oregon. The author discusses the particular attributes of the Diigo platform when it comes to finding, sharing, and collectively exploring online resources, paying close attention to where Diigo sits on the landscape of social networking sites. Drawing on a handful of examples across two graduate-level classes, the author also details the kinds of assignments and pedagogical strategies into which the author has woven Diigo as a collaborative tool. The chapter concludes with a critical assessment of the ways in which Diigo resonates with ideas of networked learning by foregrounding collaboration and participation in educational settings.
Brevity is the Soul of Wit
Authors: Ullyot Michael
Published: November 2013

In 2011, students in an introductory course on William Shakespeare used Twitter to pose questions about the texts being read. This assignment was designed to measure students’ preconceptions about the material and to focus part of each classroom session on the “conceptual change model” used in science education. This model was adapted to the humanities by pursuing student inquiries, because research methods in text-based disciplines are equally important to domain-specific concepts. This chapter describes the backward-design principles used to promote student engagement, the assignment’s methods to measure preconceptions, and the quantitative data about student engagement and classroom activities. It offers a model for other educators to integrate Twitter and other social networking platforms into their classrooms.
Personal Learning Environments and Social Networks in the Traditional School System
Authors: Manolis Christos , Kalaitzidou Eleni
Published: November 2013

An effort to integrate new technologies in learning and school life in general has been put forward by the ministry of education in Greece with an action known as “Digital School.” One of the components of “Digital School” is the digital platform that includes all schoolbooks converted to an electronic format (e-books), enhanced with additional interactive educational material. This research focuses on how the enhanced 10th grade mathematics books could comprise a constructive learning environment beyond the classroom, facilitating pupils studying on their own and at their own pace. The results of the research show that social networks, digital tools, and the resources that pupils use on a daily basis can pave the way in this direction on condition and that they are utilized for the configuration of a PLE (Personal Learning Environment) by each pupil, which ensures the required communication and feedback between the community of pupils and teachers.
Discovery ofTrichoferus campestris(Coleoptera: Cerambycidae) in Ontario, Canada and first host record in North America
Authors: Bullas-Appleton Erin , Kimoto Troy , Turgeon Jean J.
Published: November 2013

Introductions of some forest invasive alien species result in important economic, environmental, and ecological impacts. One approach used by the Canadian Food Inspection Agency to improve the detection of these species is to collect logs from trees in declining health at high risk sites of introduction and to incubate them to obtain insects, if present.Trichoferus campestris(Faldermann) (Coleoptera: Cerambycidae) adults emerged, and live larvae were extracted, from one of two logs taken from a dying Norway maple,Acer platanoidesLinnaeus (Sapindaceae), in Mississauga, Ontario, Canada. In its native range, eastern Asia, this beetle is polyphagous, however, in North America there is no host record despite numerous interceptions of larvae in wood packaging material and captures of adults at various post-entry sites. An examination of the feeding damage caused byT. campestrisin that maple suggests this insect is not a primary pest of trees in Ontario.
Plasmodium-Specific Molecular Assays Produce Uninterpretable Results and Non-Plasmodium spp. Sequences in Field-Collected Anopheles Vectors
Authors: Harrison Genelle F. , Foley Desmond H. , Rueda Leopoldo M. , Melanson Vanessa R. , Wilkerson Richard C. , Long Lewis S. , Richardson Jason H. , Klein Terry A. , Kim Heung-Chul , Lee Won-Ja
Published: November 2013

The Malaria Research and Reference Reagent Resource–recommended PLF/UNR/VIR polymerase chain reaction (PCR) was used to detect Plasmodium vivax in Anopheles spp. mosquitoes collected in South Korea. Samples that were amplified were sequenced and compared with known Plasmodium spp. by using the PlasmoDB.org Basic Local Alignment Search Tool/n and the National Center for Biotechnology Information Basic Local Alignment Search Tool/n tools. Results show that the primers PLF/UNR/VIR used in this PCR can produce uninterpretable results and non-specific sequences in field-collected mosquitoes. Three additional PCRs (PLU/VIV, specific for 18S small subunit ribosomal DNA; Pvr47, specific for a nuclear repeat; and GDCW/PLAS, specific for the mitochondrial marker, cytB) were then used to find a more accurate and interpretable assay. Samples that were amplified were again sequenced. The PLU/VIV and Pvr47 assays showed cross-reactivity with non-Plasmodium spp. and an arthropod fungus (Zoophthora lanceolata). The GDCW/PLAS assay amplified only Plasmodium spp. but also amplified the non-human specific parasite P. berghei from an Anopheles belenrae mosquito. Detection of P. berghei in South Korea is a new finding.
Association Between Stool Enteropathogen Quantity and Disease in Tanzanian Children Using TaqMan Array Cards: A Nested Case-Control Study
Authors: Platts-Mills James A. , Gratz Jean , Mduma Esto , Svensen Erling , Amour Caroline , Liu Jie , Maro Athanasia , Saidi Queen , Swai Ndealilia , Kumburu Happiness , McCormick Benjamin J. J. , Kibiki Gibson , Houpt Eric R.
Published: November 2013

Etiologic studies of diarrhea are limited by uneven diagnostic methods and frequent asymptomatic detection of enteropathogens. Polymerase chain reaction-based stool pathogen quantification may help distinguish clinically significant infections. We performed a nested case-control study of diarrhea in infants from a community-based birth cohort in Tanzania. We tested 71 diarrheal samples and pre-diarrheal matched controls with a laboratory-developed TaqMan Array Card for 19 enteropathogens. With qualitative detection, no pathogens were significantly associated with diarrhea. When pathogen quantity was considered, rotavirus (odds ratio [OR] = 2.70 per log10 increase, P < 0.001), astrovirus (OR = 1.49, P = 0.01), and Shigella/enteroinvasive Escherichia coli (OR = 1.47, P = 0.04) were associated with diarrhea. Enterotoxigenic E. coli (0.15 SD decline in length-for-age z score after 3 months per log10 increase, P < 0.001) and Campylobacter jejuni/C. coli (0.11 SD decline, P = 0.003) in pre-diarrheal stools were associated with poor linear growth. Quantitative analysis can help refine the association between enteropathogens and disease in endemic settings.
Modeling the surface tension of complex, reactive organic–inorganic mixtures
Authors: Schwier A. N. , Viglione G. A. , Li Z. , Faye McNeill V.
Published: November 2013

Abstract. Atmospheric aerosols can contain thousands of organic compounds which impact aerosol surface tension, affecting aerosol properties such as heterogeneous reactivity, ice nucleation, and cloud droplet formation. We present new experimental data for the surface tension of complex, reactive organic–inorganic aqueous mixtures mimicking tropospheric aerosols. Each solution contained 2–6 organic compounds, including methylglyoxal, glyoxal, formaldehyde, acetaldehyde, oxalic acid, succinic acid, leucine, alanine, glycine, and serine, with and without ammonium sulfate. We test two semi-empirical surface tension models and find that most reactive, complex, aqueous organic mixtures which do not contain salt are well described by a weighted Szyszkowski–Langmuir (S-L) model which was first presented by Henning et al. (2005). Two approaches for modeling the effects of salt were tested: (1) the Tuckermann approach (an extension of the Henning model with an additional explicit salt term), and (2) a new implicit method proposed here which employs experimental surface tension data obtained for each organic species in the presence of salt used with the Henning model. We recommend the use of method (2) for surface tension modeling of aerosol systems because the Henning model (using data obtained from organic–inorganic systems) and Tuckermann approach provide similar modeling results and goodness-of-fit (χ2) values, yet the Henning model is a simpler and more physical approach to modeling the effects of salt, requiring less empirically determined parameters.
Method for the determination of concentration and stable carbon isotope ratios of atmospheric phenols
Authors: Saccon M. , Busca R. , Facca C. , Huang L. , Irei S. , Kornilova A. , Lane D. , Rudolph J.
Published: November 2013

Abstract. A method for the determination of the stable carbon isotopic composition of atmospheric nitrophenols in the gas and particulate phases is presented. It has been proposed to use the combination of concentration and isotope ratio measurements of precursor and product to test the applicability of results of laboratory studies to the atmosphere. Nitrophenols are suspected to be secondary products formed specifically from the photooxidation of volatile organic compounds. XAD-4TM resin was used as an adsorbent on quartz filters to sample ambient phenols using conventional high volume air samplers at York University in Toronto, Canada. Filters were extracted in acetonitrile, with a HPLC (high-performance liquid chromatography) clean-up step and a solid phase extraction step prior to derivatization with BSTFA (bis(trimethylsilyl) trifluoroacetamide). Concentration measurements were done with gas chromatography–mass spectrometry and gas chromatography–isotope ratio mass spectrometry was used for isotope ratio analysis. The technique presented allows for atmospheric compound-specific isotopic composition measurements for five semi-volatile phenols with an estimated accuracy of 0.3–0.5‰ at atmospheric concentrations exceeding 0.1 ng m−3 while the detection limits for concentration measurements are in the pg m−3 range. Isotopic fractionation throughout the entire extraction procedure and analysis was proven to be below the precision of the isotope ratio measurements. The method was tested by conducting ambient measurements from September to December 2011.
Measuring SO2 ship emissions with an ultra-violet imaging camera
Authors: Prata A. J.
Published: November 2013

Abstract. Over the last few years fast-sampling ultra-violet (UV) imaging cameras have been developed for use in measuring SO2 emissions from industrial sources (e.g. power plants; typical fluxes ~1–10 kg s−1) and natural sources (e.g. volcanoes; typical fluxes ~10–100 kg s−1). Generally, measurements have been made from sources rich in SO2 with high concentrations and fluxes. In this work, for the first time, a UV camera has been used to measure the much lower concentrations and fluxes of SO2 (typical fluxes ~0.01–0.1 kg s−1) in the plumes from moving and stationary ships. Some innovations and trade-offs have been made so that estimates of the fluxes and path concentrations can be retrieved in real-time. Field experiments were conducted at Kongsfjord in Ny Ålesund, Svalbard, where emissions from cruise ships were made, and at the port of Rotterdam, Netherlands, measuring emissions from more than 10 different container and cargo ships. In all cases SO2 path concentrations could be estimated and fluxes determined by measuring ship plume speeds simultaneously using the camera, or by using surface wind speed data from an independent source. Accuracies were compromised in some cases because of the presence of particulates in some ship emissions and the restriction of single-filter UV imagery, a requirement for fast-sampling (>10 Hz) from a single camera. Typical accuracies ranged from 10–30% in path concentration and 10–40% in flux estimation. Despite the ease of use and ability to determine SO2 fluxes from the UV camera system, the limitation in accuracy and precision suggest that the system may only be used under rather ideal circumstances and that currently the technology needs further development to serve as a method to monitor ship emissions for regulatory purposes.
Bioavailability of riverine dissolved organic matter in three Baltic Sea estuaries and the effect of catchment land use
Authors: Asmala E. , Autio R. , Kaartokallio H. , Pitkänen L. , Stedmon C. A. , Thomas D. N.
Published: November 2013

Abstract. The microbial degradation of dissolved organic carbon and nitrogen (DOC, DON) was studied in three Finnish boreal estuaries with contrasting land use patterns (Kiiminkijoki – natural forest and peatland; Kyrönjoki – agricultural; Karjaanjoki – mixed/urban). Bioassays of 12–18 d long durations were used in 3 seasons at in situ temperatures. Besides the bulk parameters, a suite of dissolved organic matter (DOM) quality parameters were also investigated, including colored DOM (CDOM), fluorescent DOM and the molecular weight of DOM. Bioavailable DOC and DON pools varied significantly between the estuaries, from 7.9 to 10.6% and from 5.5 to 21.9%, respectively. DOM originating from the catchment dominated by natural forests and peatlands (Kiiminkijoki) had the lowest DOC and DON degradation rates, as well as the lowest proportions of biodegradable DOC and DON. A greater proportion of agricultural land in the catchment increased the bioavailability of DON, but not the bioavailability of DOC (Kyrönjoki). Additionally, DOM quality varied significantly between the estuaries, and DOM originating from the agricultural Kyrönjoki catchment sustained higher DOC and DON degradation rates and higher bacterial growth efficiency (BGE) compared to those of the natural forest and peat dominated Kiiminkijoki catchment. The quality of DOM, indicated by differences in CDOM, fluorescent DOM and molecular weight, varied between estuaries with differing land use and was concluded to be major driver of BGE of these systems and thereafter to the microbial CO2 fluxes from the estuaries. The differences in BGE resulted in a 5-fold difference in the calculated daily bacterial CO2 emissions between the study's estuaries due to bacterial activity, ranging from 40 kg C d−1 in the Karjaanjoki estuary to 200 kg C d−1 in the Kyrönjoki estuary. Lower DOC:DON ratios, smaller molecular weight and higher CDOM absorption spectral slope values of DOM resulted in higher proportion of the initial DOC and DON being transferred to microbial growth and therefore to the pelagic food web. The pristine, peatland and forest-dominated Kiiminkijoki catchment had the lowest BGE, and therefore proportionally highest CO2 fluxes.
Methane and nitrous oxide fluxes from the tropical Andes
Authors: Teh Y. A. , Diem T. , Jones S. , Huaraca Quispe L. P. , Baggs E. , Morley N. , Richards M. , Smith P. , Meir P.
Published: November 2013

Abstract. Remote sensing and inverse modelling studies indicate that the tropics emit more CH4 and N2O than predicted by bottom-up emissions inventories, suggesting that terrestrial sources are stronger or more numerous than previously thought. Tropical uplands are a potentially large and important source of CH4 and N2O often overlooked by past empirical and modelling studies. To address this knowledge gap, we investigated spatial, temporal and environmental trends in CH4 and N2O fluxes across a~long elevation gradient (600–3700 m a.s.l.) in the Kosñipata Valley, in the southern Peruvian Andes that experiences seasonal fluctuations in rainfall. The aim of this work was to produce preliminary estimates of CH4 and N2O fluxes from representative habitats within this region, and to identify the proximate controls on soil CH4 and N2O dynamics. Ecosystems across this altitudinal gradient were both atmospheric sources and sinks of CH4 on an annual basis. Montane grasslands (or, puna; 3200–3700 m a.s.l.) were strong atmospheric sources, emitting 56.94 ± 7.81kg CH4-C ha−1 yr−1. Upper montane forest (2200–3200 m a.s.l.) and lower montane forest (1200–2200 m a.s.l.) were net atmospheric sinks (−2.99 ± 0.29 kg CH4-C ha−1 yr−1 and −2.34 ± 0.29 kg CH4-C ha−1 yr−1, respectively); while premontane forests (600–1200 m a.s.l.) fluctuated between source or sink depending on the season (wet season: 1.86 ± 1.50 CH4-C ha−1 yr−1; dry season: −1.17 ± 0.40 CH4-C ha−1 yr−1). Analysis of spatial, temporal and environmental trends in CH4 flux across the study site suggest that soil redox was a dominant control on net CH4 flux. CH4 emissions were greatest from elevations, landforms and during times of year when soils were sub-oxic, and CH4 efflux was inversely correlated with soil O2 concentration (r2 = 0.82, F1, 125 = 588.41, P < 0.0001). Ecosystems across the region were net atmospheric N2O sources. N2O fluxes declined with increasing elevation; N2O emissions from premontane forest, lower montane forest, upper montane forest and montane grasslands averaged 2.23 ± 1.31 kg N2O-N ha−1 yr−1, 1.68 ± 0.44 kg N2O-N ha−1 yr−1, 0.44 ± 0.47 kg N2O-N ha−1 yr−1 and 0.15 ± 1.10 kg N2O-N ha−1 yr−1, respectively. N2O fluxes from premontane and lower montane forests exceeded prior model predictions for the region. Comprehensive investigation of field and laboratory data collected in this study suggest that N2O fluxes from this region were primarily driven by denitrification; that nitrate (NO3−) availability was the principal constraint on N2O fluxes; and that soil moisture and water-filled porosity played a secondary role in modulating N2O emissions. Any current and future changes in N management or anthropogenic N deposition may cause shifts in net N2O fluxes from these tropical montane ecosystems, further enhancing this emission source.
Model reactions and natural occurrence of furans from hypersaline environments
Authors: Krause T. , Tubbesing C. , Benzing K. , Schöler H. F.
Published: November 2013

Abstract. Volatile organic compounds like furan and its derivatives are important for atmospheric properties and reactions. In this paper the known abiotic formation of furan from catechol under Fenton-like conditions with Fe3+ sulphate was revised by the use of a bispidine Fe2+ complex as a~model compound for iron with well-known characteristics. While total yields were comparable to those with the Fe3+ salt, the turnover numbers of the active iron species increased. Additionally, the role of iron and pH will be discussed during furan formation from model compounds and in natural sediment and water samples collected from the Dead Sea and several salt lakes in Western Australia. Various alkylated furans and even traces of halogenated furans (3-chlorofuran and 3-bromofuran) were found in these samples. Furthermore, the emission of furans is compared to the abundance of several possible precursors such as isoprene and aromatic hydrocarbons as well as to the related thiophenes. It is assumed that the emissions of volatile organic compounds such as furans contribute to the formation of ultra fine particles in the vicinity of salt lakes and are therefore important for the local climate.
Multivariate statistic and time series analyses of grain-size data in quaternary sediments of Lake El'gygytgyn, NE Russia
Authors: Francke A. , Wennrich V. , Sauerbrey M. , Juschus O. , Melles M. , Brigham-Grette J.
Published: November 2013

Abstract. Lake El'gygytgyn, located in the Far East Russian Arctic, was formed by a meteorite impact about 3.58 Ma ago. In 2009, the International Continental Scientific Drilling Program (ICDP) at Lake El'gygytgyn obtained a continuous sediment sequence of the lacustrine deposits and the upper part of the impact breccia. Here, we present grain-size data of the past 2.6 Ma. General downcore grain-size variations yield coarser sediments during warm periods and finer ones during cold periods. According to principal component analysis (PCA), the climate-dependent variations in grain-size distributions mainly occur in the coarse silt and very fine silt fraction. During interglacial periods, accumulation of coarser material in the lake center is caused by redistribution of clastic material by a wind-induced current pattern during the ice-free period. Sediment supply to the lake is triggered by the thickness of the active layer in the catchment and the availability of water as a transport medium. During glacial periods, sedimentation at Lake El'gygytgyn is hampered by the occurrence of a perennial ice cover, with sedimentation being restricted to seasonal moats and vertical conduits through the ice. Thus, the summer temperature predominantly triggers transport of coarse material into the lake center. Time series analysis that was carried out to gain insight into the frequency of the grain-size data showed variations predominately on 98.5, 40.6, and 22.9 kyr oscillations, which correspond to Milankovitch's eccentricity, obliquity and precession bands. Variations in the relative power of these three oscillation bands during the Quaternary suggest that sedimentation processes at Lake El'gygytgyn are dominated by environmental variations caused by global glacial–interglacial variations (eccentricity, obliquity), and local insolation forcing and/or latitudinal teleconnections (precession), respectively.
Where to find 1.5 million yr old ice for the IPICS "Oldest-Ice" ice core
Authors: Fischer H. , Severinghaus J. , Brook E. , Wolff E. , Albert M. , Alemany O. , Arthern R. , Bentley C. , Blankenship D. , Chappellaz J. , Creyts T. , Dahl-Jensen D. , Dinn M. , Frezzotti M. , Fujita S. , Gallee H. , Hindmarsh R. , Hudspeth D. , Jugie G. , Kawamura K. , Lipenkov V. , Miller H. , Mulvaney R. , Parrenin F. , Pattyn F. , Ritz C. , Schwander J. , Steinhage D. , van Ommen T. , Wilhelms F.
Published: November 2013

Abstract. The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic disturbance and should be able to be recovered after careful pre-site selection studies. Based on a simple ice and heat flow model and glaciological observations, we conclude that positions in the vicinity of major domes and saddle position on the East Antarctic Plateau will most likely have such old ice in store and represent the best study areas for dedicated reconnaissance studies in the near future. In contrast to previous ice core drill site selections, however, we strongly suggest significantly reduced ice thickness to avoid bottom melting. For example for the geothermal heat flux and accumulation conditions at Dome C, an ice thickness lower than but close to about 2500 m would be required to find 1.5 Myr old ice (i.e., more than 700 m less than at the current EPICA Dome C drill site). Within this constraint, the resolution of an Oldest-Ice record and the distance of such old ice to the bedrock should be maximized to avoid ice flow disturbances, for example, by finding locations with minimum geothermal heat flux. As the geothermal heat flux is largely unknown for the EAIS, this parameter has to be carefully determined beforehand. In addition, detailed bedrock topography and ice flow history has to be reconstructed for candidates of an Oldest-Ice ice coring site. Finally, we argue strongly for rapid access drilling before any full, deep ice coring activity commences to bring datable samples to the surface and to allow an age check of the oldest ice.
Large scale analysis of changing frequencies of rain-on-snow events and their impact on floods
Authors: Freudiger D. , Kohn I. , Stahl K. , Weiler M.
Published: November 2013

Abstract. In January 2011 a rain-on-snow (RoS) event caused floods in the major river basins in Central Europe, i.e. the Rhine, Danube, Weser, Elbe, Oder, Ems basins. This event prompted the question how to define a RoS event and whether those events have become more frequent. Based on the flood of January 2011 and on other known events of the past, threshold values for RoS events were determined and consequently events which combine average rainfall of at least 3 mm on a snowpack of at least 10 mm snow water equivalent (SWE) as well as 20% melt content by summing rainfall and snowmelt were analysed. RoS events were estimated for the last 61 yr and for the entire study area based on a temperature-index snow model driven with the European-scale E-OBS data. Frequencies and magnitude differ depending on the elevation range. When distinguishing alpine, upland, and lowland basins, we found that upland basins are most influenced by RoS events. Over the last decades their occurrences shifted from late to early winter. Overall, the frequency of rainfall increased in the winter, while the frequency of snowfall decreased in the spring. In nearly all lowland and upland basins an increasing trend in the frequency of RoS events since 1980 was observed. These results suggest an increasing flood hazard from RoS events in January and February in the medium mountain ranges of Central Europe, especially in the Rhine, Weser, and Elbe river basins.
Coevolution of water security in a developing city
Authors: Srinivasan V.
Published: November 2013

Abstract. The world is rapidly urbanizing. One of the challenges associated with this growth will be to supply water to rapidly growing, developing-world cities. While there is a long history of interdisciplinary research in water resources management, relatively few water studies attempts to explain why water systems evolve the way they do; why some regions develop sustainable, secure well-functioning water systems while others do not and which feedbacks force the transition from one trajectory to the other. This paper attempts to tackle this question by examining the historical evolution of one city in Southern India. A key contribution of this paper is the co-evolutionary modelling approach adopted. The paper presents a "socio-hydrologic" model that simulates the feedbacks between the human, engineered and hydrologic system for Chennai, India over a forty year period and evaluates the implications for water security. This study offers some interesting insights on urban water security in developing country water systems. First, the Chennai case study argues that urban water security goes beyond piped water supply. When piped supply fails users first depend on their own wells. When the aquifer is depleted, a tanker market develops. When consumers are forced to purchase expensive tanker water, they are water insecure. Second, different initial conditions result in different water security trajectories. However, initial advantages in infrastructure are eroded if the utility's management is weak and it is unable to expand or maintain the piped system to keep up with growth. Both infrastructure and management decisions are necessary to achieving water security. Third, the effects of mismanagement do not manifest right away. Instead, in the manner of a "frog in a pot of boiling water", the system gradually deteriorates. The impacts of bad policy may not manifest till much later when the population has grown and a major multi-year drought hits.
Dynamic risk simulation to assess natural hazards risk along roads
Authors: Voumard J. , Caspar O. , Derron M.-H. , Jaboyedoff M.
Published: November 2013

Abstract. Risk generated by natural hazards on roads is usually calculated with equations integrating various parameters related to hazard and traffic. These are static variables, like an average number of vehicles crossing this section every day and an average vehicle speed. This methodology cannot take into account dynamic variations of traffic and interactions between vehicles such as speed modifications due to windy roads, slowdowns resulting from saturated traffic or vehicle tailbacks forming in front of traffic lights. Here we show, by means of a dynamic traffic simulator, that traffic variations may greatly influence the risk estimation over time. The risk is analysed on several sections of an Alpine road in Switzerland using a dynamic vehicles approach, and compared with the results of the static methodology. It demonstrates that risk can significantly increase on sinuous sections because of decreasing vehicle speed. For example, along an 800 m-long section of road containing two hairpin bends, the dynamic risk is about 50% higher than the static one. Badly placed signalization, slowing down, or stopping the vehicles in a hazardous area may increase the risk by about 150% (i.e. 2.5 times higher) along a straight road section where vehicles speed is high. A more realistic risk can thus be obtained from a dynamic approach, especially on mountain roads. The dynamic traffic simulator developed for this work appears to be a helpful tool to support decision-making in reducing risk on mountain roads and it shows the importance of keeping the traffic moving as freely as possible.
Recent land subsidence caused by the rapid urban development in the Hanoi urban region (Vietnam) using ALOS InSAR data
Authors: Dang V. K. , Doubre C. , Weber C. , Masson F. , Gourmelen N.
Published: November 2013

Abstract. Since the 1990s the land subsidence due to the rapid urbanization has been considered a severely destructive hazard in the center of Hanoi City. Although previous studies and measurements have quantified the subsiding deformation in Hanoi center, no data exist for the newly established districts in the south and the west, where construction development has been most significant and where groundwater pumping has been very intensive over the last decade. With a multi-temporal InSAR approach, we quantify the spatial distribution of the land subsidence in the whole Hanoi urban region using ALOS images over the 2007–2011 period. The map of the mean subsidence velocity reveals that the northern bank of the Red River appears stable, whereas some areas in southern bank are subsiding with a mean vertical rate up to 68 mm yr−1, especially within the three new urban districts of Hoang Mai, Ha Dong and Hoai Duc. We interpret the spatial distribution of the surface deformation as the combination of the nature of the unsaturated layer, the lowering of groundwater in the aquifers due to pumping withdrawal capacity, the increase of built-up surfaces and the type of building foundation. The time evolution deduced from the InSAR time series is consistent with previous leveling data and shows that the lowering rate of the surface slightly decreases till 2008. Then, a seasonal variation suggests that the deformation became non-stationary, with upward and downward transient displacements related to the charge and discharge of the aquifer following the changes between rainy and dry seasons.
Halley Research Station, Antarctica: calving risks and monitoring strategies
Authors: Anderson R. , Jones D. H. , Gudmundsson G. H.
Published: November 2013

Abstract. The British Antarctic Survey's Halley Research Station is located on the Brunt Ice Shelf, Antarctica, where it is potentially vulnerable to calving events. Existing historical records show that the Brunt Ice Shelf is currently extended further into the Weddell Sea than it was before its last large calving event, so a new calving event may be overdue. We describe three different possible future scenarios for a large-scale calving event on Brunt Ice Shelf, and conclude that the currently most threatening scenario for the Halley Research Station is a calving event on the neighbouring Stancomb–Wills Glacier Tongue, with subsequent detrimental consequences for the stability of the Brunt Ice Shelf. Based on available data, we suggest an increasing likelihood of this scenario occurring after 2020. We furthermore describe ongoing monitoring efforts aimed at giving advanced warning of an imminent calving event.
First air–sea gas exchange laboratory study at hurricane wind speeds
Authors: Krall K. E. , Jähne B.
Published: November 2013

Abstract. In a pilot study conducted in October and November 2011, air–sea gas transfer velocities of the two sparingly soluble trace gases hexafluorobenzene and 1,4-difluorobenzene were measured in the unique High-Speed Wind-Wave Tank at Kyoto University, Japan. This air–sea interaction facility is capable of producing hurricane strength wind speeds of up to u10=67 m s−1. This constitutes the first lab study of gas transfer at such high wind speeds. The measured transfer velocities k600 spanned two orders of magnitude, lying between 11 cm h−1 and 1180 cm h−1 with the latter being the highest ever measured wind induced gas transfer velocity. The measured gas transfer velocities are in agreement with the only available dataset at hurricane wind speeds (McNeil and D'Asaro, 2007). The disproportionately large increase of the transfer velocities found at highest wind speeds indicates a new regime of air–sea gas transfer, which is characterized by strong wave breaking, enhanced turbulence and bubble cloud entrainment. It was found that tracers spanning a wide range of solubilities and diffusivities are needed to separate the effects of enhanced surface area and turbulence due to breaking waves from the effects of bubble and spray mediated gas transfer.
On the tides and resonances of Hudson Bay and Hudson Strait
Authors: Webb D. J.
Published: November 2013

Abstract. The resonances of Hudson Bay, Foxe Basin and Hudson Strait are investigated using a~linear shallow water numerical model. The region is of particular interest because it is the most important region of the world ocean for dissipating tidal energy. The model shows that the semi-diurnal tides of the region are dominated by four nearby overlapping resonances. It shows that these not only affect Ungava Bay, a region of extreme tidal range, but they also extend far into Foxe Basin and Hudson Bay and appear to be affected by the geometry of those regions. The results also indicate that it is the four resonances acting together which make the region such an important area for dissipating tidal energy.
Impact of varying debris cover thickness on catchment scale ablation: a case study for Koxkar glacier in the Tien Shan
Authors: Juen M. , Mayer C. , Lambrecht A. , Haidong H. , Shiyin L.
Published: November 2013

Abstract. To quantify the ablation processes on a debris covered glacier, a simple distributed ablation model has been developed and applied to a selected glacier. For this purpose, a bundle of field measurements was carried out to collect empirical data. A morphometric analysis of the glacier surface enables us to statistically capture the areal distribution of topographic features that influence debris thickness and consequently ablation. Remote sensing techniques, using high resolution satellite imagery, were used to extrapolate the ground truth results to the whole ablation area and to map and classify melt-relevant surface types. As a result, a practically applicable method is presented, that allows the estimation of ablation on a debris covered glacier by combining field data and remote sensing information. The sub-debris ice ablation accounts for about 19% of the entire ice ablation, while the percentage of the moraine covered area accounts for approximately 32% of the entire glacerized area. Although the ice cliffs occupy only 1.7% of the debris covered area the melt amount accounts for approximately 15% of the total sub-debris ablation and 2.7% of the total ablation respectively. Our study highlights the influence of debris cover on the response of the glacier terminus to climate warming. Due to the fact that melt rates beyond 0.1m of moraine cover are highly restricted the shielding effect of the debris cover dominates over the temperature- and elevation dependence of the ablation in the bare ice case.
Hydrochemical composition of thermokarst lake waters in the permafrost zone of western Siberia within the context of climate change
Authors: Manasypov R. M. , Pokrovsky O. S. , Kirpotin S. N. , Shirokova L. S.
Published: November 2013

Abstract. This work describes the current state of thaw lake and pond ecosystems, the mechanisms of their formation and succession, which was assessed via field work during several summer campaigns, and the laboratory analysis of water samples that were collected in the northern part of western Siberia within continuous and discontinuous permafrost zones. We analyzed the elemental chemical composition of lake waters as a function of lake diameter, over more than two orders of magnitude of the lake size, and described the peculiarities of the elemental composition of the thermokarst water body ecosystem during various stages of lake development. We revealed significant correlations between Fe, Al and dissolved organic carbon (DOC) and various chemical elements across a latitude gradient of approximately 900 km. Several groups of chemical elements were distinguished that reflect the dynamic succession of the studied area of water bodies. Combining the data of the studied latitude profile with the information available in the current literature demonstrated that the average dissolved elemental concentrations in lakes of different size ranges exhibit specific dependencies on the latitude position, which is presumably linked to (1) leaching of the elements from frozen peat, which is the main source of solutes in thermokarst lakes, (2) marine atmospheric aerosol depositions, notably at the proximity to the sea border, and (3) short-range industrial pollution of certain metals from the largest Russian arctic smelter. We discuss the evolution of thermokarst lake chemical compositions during their formation and drainage and foresee the consequences of climate warming and permafrost thaw on the hydrochemistry of the thaw lakes and ponds of western Siberia.
Neuroscience and Sartre's Account of Bad Faith
Authors: Valentine John
Published: November 2013

The article explores the possibility that studies in cerebral commissurotomy (severing of the corpus callosum) may shed some light on Jean-Paul Sartre's account of bad faith. I examine this issue from both a descriptive and an explanatory point of view. My conclusion is that Sartre and various neuroscientists seem generally to agree on the description of self-deception, but they substantially disagree on how the phenomenon is to be explained. I argue that Sartre's account does not seem fully adequate, while the neuroscientific approach may have explanatory potential if certain conceptual issues are resolved. I also argue that, carefully delimited, the neuroscientific stance complements Sartre's approach.
Polanyi, Universals, and the Nominalism Controversy
Authors: Fennell Jon
Published: November 2013

During and after World War II Michael Polanyi emerged from the world of science as a major philosopher with a distinctive voice and perspective that even now influences inquirers in a remarkably wide variety of disciplines. Among Polanyi's central contributions is a critique of nominalism and a corresponding defense of universals and general ideas that succeeds precisely because it eschews the categories and antinomies that mark the traditional controversy between realists and nominalists. There are striking parallels between Polanyi's position and that of C. S. Peirce. Each offers an escape from nominalism that is predicated on a fundamental reconceptualization of the controversy. While providing a fresh perspective on the challenge of nominalism, Polanyi also casts important clarifying light on the phenomenon of induction.
Pyrrhonian Skepticism and the Mirror of Nature
Authors: Leach Stephen
Published: November 2013

This article discusses a problem that arises from Richard Rorty's use of both Kuhn and Davidson to criticize putative truth criteria. I argue that there is a conflict between the positions of Kuhn and Davidson that Rorty fails to notice. However, Rorty need not choose between them, for, ironically—since Rorty is in large part motivated by putting skepticism to rest—this dilemma is avoided if his insights are instead bolstered by the support of Pyrrhonian skepticism. With the help of this support, not only do Rorty's criticisms of the mirror of nature retain their force, but (contra Rorty) philosophy retains its autonomy.
A network of heterochronic genes including Imp1 regulates temporal changes in stem cell properties
Authors: Nishino Jinsuke , Kim Sunjung , Zhu Yuan , Zhu Hao , Morrison Sean J
Published: November 2013

Stem cell properties change over time to match the changing growth and regeneration demands of tissues. We showed previously that adult forebrain stem cell function declines during aging because of increased expression of let-7 microRNAs, evolutionarily conserved heterochronic genes that reduce HMGA2 expression. Here we asked whether let-7 targets also regulate changes between fetal and adult stem cells. We found a second let-7 target, the RNA binding protein IMP1, that is expressed by fetal, but not adult, neural stem cells. IMP1 expression was promoted by Wnt signaling and Lin28a expression and opposed by let-7 microRNAs. Imp1-deficient neural stem cells were prematurely depleted in the dorsal telencephalon due to accelerated differentiation, impairing pallial expansion. IMP1 post-transcriptionally inhibited the expression of differentiation-associated genes while promoting the expression of self-renewal genes, including Hmga2. A network of heterochronic gene products including Lin28a, let-7, IMP1, and HMGA2 thus regulates temporal changes in stem cell properties.
BRAF inhibitors suppress apoptosis through off-target inhibition of JNK signaling
Authors: Vin Harina , Ojeda Sandra S , Ching Grace , Leung Marco L , Chitsazzadeh Vida , Dwyer David W , Adelmann Charles H , Restrepo Monica , Richards Kristen N , Stewart Larissa R , Du Lili , Ferguson Scarlett B , Chakravarti Deepavali , Ehrenreiter Karin , Baccarini Manuela , Ruggieri Rosamaria , Curry Jonathan L , Kim Kevin B , Ciurea Ana M , Duvic Madeleine , Prieto Victor G , Ullrich Stephen E , Dalby Kevin N , Flores Elsa R , Tsai Kenneth Y
Published: November 2013

Vemurafenib and dabrafenib selectively inhibit the v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) kinase, resulting in high response rates and increased survival in melanoma. Approximately 22% of individuals treated with vemurafenib develop cutaneous squamous cell carcinoma (cSCC) during therapy. The prevailing explanation for this is drug-induced paradoxical ERK activation, resulting in hyperproliferation. Here we show an unexpected and novel effect of vemurafenib/PLX4720 in suppressing apoptosis through the inhibition of multiple off-target kinases upstream of c-Jun N-terminal kinase (JNK), principally ZAK. JNK signaling is suppressed in multiple contexts, including in cSCC of vemurafenib-treated patients, as well as in mice. Expression of a mutant ZAK that cannot be inhibited reverses the suppression of JNK activation and apoptosis. Our results implicate suppression of JNK-dependent apoptosis as a significant, independent mechanism that cooperates with paradoxical ERK activation to induce cSCC, suggesting broad implications for understanding toxicities associated with BRAF inhibitors and for their use in combination therapies.
Introducing Samples Directly into Electrospray Ionization Mass Spectrometers by Direct Infusion Using a Nanoelectrospray Interface
Authors: Lee Terry D. , Moore Roger E. , Keen Denise
Published: November 2013

Procedures are described for constructing and using a microscale electrospray interface for direct infusion of samples into mass spectrometers. The sensitivity of the nanospray interface is a result of greatly reducing the flow of sample solution while preserving the analyte signal intensity. The described methodology provides a simple and robust way to analyze individual purified peptide and protein samples, i.e., samples that do not require liquid chromatography separation. Curr. Protoc. Protein Sci. 74:16.8.1‐16.8.7. © 2013 by John Wiley & Sons, Inc.
Pulsed EPR Distance Measurements in Soluble Proteins by Site‐Directed Spin Labeling (SDSL)
Authors: de Vera Ian Mitchelle S. , Blackburn Mandy E. , Galiano Luis , Fanucci Gail E.
Published: November 2013

The resurgence of pulsed electron paramagnetic resonance (EPR) in structural biology centers on recent improvements in distance measurements using the double electron‐electron resonance (DEER) technique. This unit focuses on EPR‐based distance measurements by site‐directed spin labeling (SDSL) of engineered cysteine residues in soluble proteins, with HIV‐1 protease used as a model. To elucidate conformational changes in proteins, experimental protocols were optimized and existing data analysis programs were employed to derive distance‐distribution profiles. Experimental considerations, sample preparation, and error analysis for artifact suppression are also outlined herein. Curr. Protoc. Protein Sci. 74:17.17.1‐17.17.29. © 2013 by John Wiley & Sons, Inc.
Methods for Studying Interactions of Detergents and Lipids with α‐Helical and β‐Barrel Integral Membrane Proteins
Authors: Saif Hasan S. , Baniulis Danas , Yamashita Eiki , Zhalnina Mariya V. , Zakharov Stanislav D. , Stofleth Jason T. , Cramer William A.
Published: November 2013

Methods for studying interactions of protein with lipids and detergents are described for representatives of two major classes of membrane proteins: (1) the α‐helical hetero‐oligomeric integral cytochrome b6f complex of oxygenic photosynthesis from cyanobacteria, and (2) the outer membrane β‐barrel proteins BtuB and OmpF from Gram‐negative Escherichia coli bacteria. Details are presented on the use of detergents for purification and crystallization of the b6f complex as well as a method for lipid exchange. The positions of detergent and lipid molecules, which define eight potential lipid‐binding sites in the b6f complex, are described. Differences in detergent strategies for isolation and crystallization of β‐barrel proteins relative to those for oligomeric helical membrane proteins are discussed, and purification and assessment of protein quality by circular dichroism (CD) is presented. Curr. Protoc. Protein Sci. 74:29.7.1‐29.7.30. © 2013 by John Wiley & Sons, Inc.