bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhabited Pasts: Monuments, Authority, and People in Delhi, 1912–1970s
Authors: Sutton Deborah
Published: September 2018

This article considers the relationship between the official, legislated claims of heritage conservation in India and the wide range of episodic and transitory inhabitations that have animated and transformed the monumental remains of the city, or rather cities, of Delhi. Delhi presents a spectrum of monumental structures that appear variously to either exist in splendid isolation from the rush of everyday urban life or to peek out amidst a palimpsest of unplanned, urban fabric. The repeated attempts of the state archaeological authorities to disambiguate heritage from the quotidian life of the city was frustrated by bureaucratic lapses, casual social occupations, and deliberate challenges. The monuments offered structural and spatial canvases for lives within the city, providing shelter, solitude, and the possibility of privacy, as well as devotional and commercial opportunity. The dominant comportment of the city's monuments during the twentieth century was a hybrid monumentality, in which the jealous, legislated custody of the state became anxious, ossified, and ineffectual. An acknowledgement and acceptance of the hybridity of Delhi's monuments offers an opportunity to reorient understandings of urban heritage.
Risk and Return in High-Frequency Trading
Authors: Baron Matthew , Brogaard Jonathan , Hagströmer Björn , Kirilenko Andrei
Published: September 2018

We study performance and competition among firms engaging in high-frequency trading (HFT). We construct measures of latency and find that differences in relative latency account for large differences in HFT firms’ trading performance. HFT firms that improve their latency rank due to colocation upgrades see improved trading performance. The stronger performance associated with speed comes through both the short-lived information channel and the risk management channel, and speed is useful for various strategies, including market making and cross-market arbitrage. We find empirical support for many predictions regarding relative latency competition.
Bank Interventions and Trade Credit: Evidence from Debt Covenant Violations
Authors: Zhang Zilong
Published: September 2018

This study examines the consequences of conflicts between creditors. Using the setting of debt covenant violations, I employ a regression discontinuity design to identify the effect of banks’ interventions on their borrowers’ trade credit. The results show that trade credit experiences a substantial decline when banks intervene in the borrowing firm following covenant violations. The decline is mitigated by the presence of dependent suppliers and exacerbated by banks’ incentives to exercise control rights. Such externalities are reflected in the loan-contract design. Borrowing firms sign less restrictive loan contracts when they rely more on trade credit or trade creditors.
High-Frequency Trading Competition
Authors: Brogaard Jonathan , Garriott Corey
Published: September 2018

Theory on high-frequency traders (HFTs) predicts that market liquidity for a security decreases in the number of HFTs trading the security. We test this prediction by studying a new Canadian stock exchange, Alpha, that experienced the entry of 11 HFTs over 4 years. We find that bid–ask spreads on Alpha converge to those at the Toronto Stock Exchange as more HFTs trade on Alpha. Effective and realized spreads for non-HFTs improve as HFTs enter the market. To explain the contrast with theory, which models the HFT as a price competitor, we provide evidence more consistent with HFTs fitting a quantity-competitor framework.
The Modern and the Political Pluralist Perspectives on Political Authorities
Authors: Allard-Tremblay Yann
Published: September 2018

I contrast two perspectives adopted to theorize political authorities. The first is the modern perspective. It conceives of political society as a civic union of free and equal citizens and regards the state as the political organization of this society. This perspective is primarily concerned with the principles that should govern the use of state power. The second is the political pluralist perspective. It recognizes a multiplicity of normative orders as equally legitimate. The focus is put on the civic processes by which a diverse citizenry should negotiate its interactions. I illustrate these perspectives by considering how they approach diversity, and more specifically the political claims of indigenous peoples. The pluralist perspective is argued to be normatively motivated by a consideration for the actual freedom of citizens to sustain diverse normative orders, to negotiate the structure of political society, and to jointly search for justice.
DiarrhoeagenicEscherichia coliandEscherichia albertiiin Brazil: pathotypes and serotypes over a 6-year period of surveillance
Authors: Ori E. L. , Takagi E. H. , Andrade T. S. , Miguel B. T. , Cergole-Novella M. C. , Guth B. E. C. , Hernandes R. T. , Dias R. C. B. , Pinheiro S. R. S. , Camargo C. H. , Romero E. C. , Dos Santos L. F.
Published: September 2018

DiarrhoeagenicEscherichia coli(DEC) is a leading cause of infectious diarrhoea worldwide. In recent years,Escherichia albertiihas also been implicated as a cause of human enteric diseases. This study describes the occurrence ofE. colipathotypes and serotypes associated with enteric illness and haemolytic uremic syndrome (HUS) isolated in Brazil from 2011 to 2016. Pathotypes isolated included enteropathogenicE. coli(EPEC), enteroaggregativeE. coli(EAEC), enterotoxigenicE. coli(ETEC), enteroinvasiveE. coli(EIEC) and Shiga toxin-producingE. coli(STEC). PCR of stool enrichments for DEC pathotypes was employed, andE. albertiiwas also sought. O:H serotyping was performed on all DEC isolates. A total of 683 DEC and 10E. albertiistrains were isolated from 5047 clinical samples. The frequencies of DEC pathotypes were 52.6% (359/683) for EPEC, 32.5% for EAEC, 6.3% for ETEC, 4.4% for EIEC and 4.2% for STEC. DEC strains occurred in patients from 3 months to 96 years old, but EPEC, EAEC and STEC were most prevalent among children. Both typical and atypical isolates of EPEC and EAEC were recovered and presented great serotype heterogeneity. HUS cases were only associated with STEC serotype O157:H7. TwoE. albertiiisolates belonged to serogroup O113 and one had thestx2f gene. The higher prevalence of atypical EPEC in relation to EAEC in community-acquired diarrhoea in Brazil suggests a shift in the trend of DEC pathotypes circulation as previously EAEC predominated. This is the first report ofE. albertiiisolation from active surveillance. These results highlight the need of continuing DEC andE. albertiisurveillance, as a mean to detect changes in the pattern of pathotypes and serotypes circulation and provide useful information for intervention and control strategies.
A Meta-Analysis of Test Scores in Proctored and Unproctored Ability	Assessments
Authors: Steger Diana , Schroeders Ulrich , Gnambs Timo
Published: September 2018

Abstract. Unproctored, web-based assessments are frequently compromised by a lack of control over the participants’ test-taking behavior. It is likely that participants cheat if personal consequences are high. This meta-analysis summarizes findings on context effects in unproctored and proctored ability assessments and examines mean score differences and correlations between both assessment contexts. As potential moderators, we consider (a) the perceived consequences of the assessment, (b) countermeasures against cheating, (c) the susceptibility to cheating of the measure itself, and (d) the use of different test media. For standardized mean differences, a three-level random-effects meta-analysis based on 109 effect sizes from 49 studies (total N = 100,434) identified a pooled effect of Δ = 0.20, 95% CI [0.10, 0.31], indicating higher scores in unproctored assessments. Moderator analyses revealed significantly smaller effects for measures that are difficult to research on the Internet. These results demonstrate that unproctored ability assessments are biased by cheating. Unproctored assessments may be most suitable for tasks that are difficult to search on the Internet.
Indications of Dynamic Effects on Scaling Relationships Between Channel Sinuosity and Vegetation Patch Size Across a Salt Marsh Platform
Authors: Taramelli Andrea , Valentini Emiliana , Cornacchia Loreta , Monbaliu Jaak , Sabbe Koen
Published: September 2018

Salt marshes are important coastal areas that consist of a vegetated intertidal marsh platform and a drainage network of tidal channels. How salt marshes and their drainage networks develop is not fully understood, but it has been shown that the biogeomorphic interactions and feedbacks between vegetation development and channel formation play an important role. We examined the relationships among tidal channel sinuosity, marsh roughness, vegetation type (pioneer, Elymus athericus or Phragmites australis), and patch size at different spatial scales using a high‐resolution vegetation map (derived from aerial photography) and lower‐resolution satellite imagery processed with linear spectral mixture analysis. The patch‐size distribution in all vegetation types corresponded to a power law, suggesting the presence of self‐organizational processes. While small vegetation patches are more dominant in pioneer vegetation, they were present in all vegetation types. The largest patch size is restricted to E. athericus. We observed an inverse logarithmic relationship between channel sinuosity and vegetation patch size in all vegetation types. The fact that this relationship is observed in both pioneer and later successional stages suggests that after the establishment of a drainage network in the dynamic pioneer stages of salt marsh development, the later stages of salt marsh succession largely inherit the meandering pattern of the early successional stages. Our study confirms recent evidence that no significant changes in the specific features of tidal channel networks (e.g., channel width, drainage density, and efficiency) take place during the later stages of salt marsh development.
Development and Application of a Large‐Scale, Physically Based, Distributed Suspended Sediment Transport Model on the Fraser River Basin, British Columbia, Canada
Authors: Tsuruta Kai , Hassan Marwan A. , Donner Simon D. , Alila Younes
Published: September 2018

Modeling sediment transport through large basins presents a challenging problem. The relation between water flux and sediment load is complex, and substantial erosion and transport can occur over small spatial and temporal scales. Analysis of large‐scale basins often relies on lumped empirical models that do not consider spatial or subannual variability. In this study, we adapt a small‐scale, mechanistic, distributed suspended sediment transport model for application to large basins. The model is integrated into the Terrestrial Hydrology Model with Biochemistry to make use of the Terrestrial Hydrology Model with Biochemistry's dynamic water routing. The coupled model is applied to the 230,000‐km2 Fraser River Basin in British Columbia, Canada, using climatic and hydrological inputs provided by a historical run of the Variable Infiltration Capacity model. Hourly simulations are aggregated into monthly and long‐term averages which are compared against observations. Simulated long‐term lake sedimentation values are within an order of magnitude of observations, and monthly load simulations have an average R2 of 0.70 across the five study stations with available data. Model results indicate that sediment loads from tributaries do not heavily influence dynamics along the main stem and suggest the importance of network connectivity. Sensitivity analysis indicates that models may benefit from characterizing bed load irrespective of its contribution to total sediment load. Historical simulations over the 1965–2004 period reveal important changes in sediment dynamics that could not be captured with a lumped model, including a decrease in basin sediment load interannual variability driven by changes in runoff and load variability within a key subbasin.
Negative Emission Potential of Direct Air Capture Powered by Renewable Excess Electricity in Europe
Authors: Wohland Jan , Witthaut Dirk , Schleussner Carl‐Friedrich
Published: September 2018

The mitigation of climate change requires fast reductions in greenhouse gas emissions and calls for fundamental transitions of energy systems. In most places, the increased exploitation of variable renewable sources (wind and solar) forms the backbone of these transitions. To remain consistent with the Paris Agreement temperature goals, negative emission technologies will likely be needed to achieve net zero emissions in the second half of the century. In integrated assessment models, negative emissions are typically realized through land‐based approaches. However, due to their coarse temporal and spatial resolution, such models might underestimate the potential of decentrally deployable and flexible technologies such as Direct Air Capture (DAC). Based on validated high‐resolution power generation time series, we show that DAC can extract CO2 from the atmosphere and facilitate the integration of variable renewables at the same time. It is a promising flexibility provider as it can be ramped within minutes. Our results show that negative emissions of up to 500 Mt CO2/year in Europe may be achievable by using renewable excess energy only. Electricity systems with high shares of volatile renewables will induce excess generation events during which electricity is cheap thereby lowering the operational costs of DAC. If investment costs can be sufficiently reduced, this may render very energy intensive but highly flexible technologies such as DAC viable.
Environmental Conditions, Ignition Type, and Air Quality Impacts of Wildfires in the Southeastern and Western United States
Authors: Brey Steven J. , Barnes Elizabeth A. , Pierce Jeffrey R. , Wiedinmyer Christine , Fischer Emily V.
Published: September 2018

This research contrasts the environmental conditions, meteorological drivers, and air quality impacts of human‐ and lightning‐ignited wildfires in the southeastern and western United States, the two continental U.S. regions with the most wildfire burn area. We use the Fire Program Analysis Wildfire Occurrence Data (FPA FOD) to determine wildfire abundance and ignition sources between 1992 and 2015. We investigate specific ecoregions within these two U.S. regions and find that in the majority of ecoregions, annual lightning‐ and human‐ignited wildfire burn area have similar relationships with key meteorological parameters. We investigate the fuel moisture values where wildfires occur segregated by ignition type and show that within a given ecoregion, the differences in median fuel moisture between ignition types are generally smaller than the differences between ecoregions. Our results suggest that annual wildfire burn area for human‐ and lightning‐ignited wildfires within a given ecoregion are modulated by environmental conditions, and climate change may similarly impact wildfires of both ignition types. Finally, we estimate fine particulate matter emissions for Fire Program Analysis Wildfire Occurrence Data wildfires using the Fire INventory from NCAR model framework. We show that emissions of fine particulate matter from human‐ignited wildfires is significant and of a similar total magnitude between the west and southeastern United States. Additionally, the west and southeast have a similar number of wildfires associated with National Weather Service air quality smoke forecasts.
Blue Carbon Storage Capacity of Temperate Eelgrass (Zostera marina) Meadows
Authors: Röhr Maria Emilia , Holmer Marianne , Baum Julia K. , Björk Mats , Boyer Katharyn , Chin Diana , Chalifour Lia , Cimon Stephanie , Cusson Mathieu , Dahl Martin , Deyanova Diana , Duffy J. Emmet , Eklöf Johan S. , Geyer Julie K. , Griffin John N. , Gullström Martin , Hereu Clara M. , Hori Masakazu , Hovel Kevin A. , Hughes A. Randall , Jorgensen Pablo , Kiriakopolos Stephanie , Moksnes Per‐Olav , Nakaoka Masahiro , O'Connor Mary I. , Peterson Bradley , Reiss Katrin , Reynolds Pamela L. , Rossi Francesca , Ruesink Jennifer , Santos Rui , Stachowicz John J. , Tomas Fiona , Lee Kun‐Seop , Unsworth Richard K. F. , Boström Christoffer
Published: September 2018

Despite the importance of coastal ecosystems for the global carbon budgets, knowledge of their carbon storage capacity and the factors driving variability in storage capacity is still limited. Here we provide an estimate on the magnitude and variability of carbon stocks within a widely distributed marine foundation species throughout its distribution area in temperate Northern Hemisphere. We sampled 54 eelgrass (Zostera marina) meadows, spread across eight ocean margins and 36° of latitude, to determine abiotic and biotic factors influencing organic carbon (Corg) stocks in Zostera marina sediments. The Corg stocks (integrated over 25‐cm depth) showed a large variability and ranged from 318 to 26,523 g C/m2 with an average of 2,721 g C/m2. The projected Corg stocks obtained by extrapolating over the top 1 m of sediment ranged between 23.1 and 351.7 Mg C/ha, which is in line with estimates for other seagrasses and other blue carbon ecosystems. Most of the variation in Corg stocks was explained by five environmental variables (sediment mud content, dry density and degree of sorting, and salinity and water depth), while plant attributes such as biomass and shoot density were less important to Corg stocks. Carbon isotopic signatures indicated that at most sites <50% of the sediment carbon is derived from seagrass, which is lower than reported previously for seagrass meadows. The high spatial carbon storage variability urges caution in extrapolating carbon storage capacity between geographical areas as well as within and between seagrass species.
Similarity in Fog and Rainfall Intermittency
Authors: Räsänen M. , Chung M. , Katurji M. , Pellikka P. , Rinne J. , Katul G. G.
Published: September 2018

Intermittent fog occurrences supply significant amounts of moisture to plants in the form of fog drip onto the soil surface thereby prompting interest in their statistical behavior at multiple timescales. A comparison of rainfall and fog measurements collected at an inland tropical cloud forest in Kenya and a coastal rangeland in Northern California is presented to explore whether fog occurrences have similar intermittency characteristics as rainfall. The results confirm that both rainfall and fog show approximate power law relations for distributions of dry period and event size consistent with predictions from self‐organized criticality. Moreover, the spectral exponents of the on‐off time series of the fog and rainfall exhibited an approximate f−0.8 over a broad range of frequencies f, which is remarkably close to scaling exponents across sites experiencing different rainfall generation mechanisms. These results suggest that fog intermittency shares some properties of critical behavior documented in numerous rainfall studies.
Unstable Eigenmodes of the Feedback Instability With Collision‐Induced Velocity Shear
Authors: Watanabe T.‐H. , Maeyama S.
Published: September 2018

A linear eigenmode analysis of the magnetosphere‐ionosphere coupling shows that the feedback instability leading to spontaneous formation of auroral arc structures remains unstable even in a case with strong vertical shear of horizontal ion flows induced by ion‐neutral collisions in the E layer. For low‐order Alfvén harmonics, the linear frequency and growth rate obtained by means of a height‐resolved model of the ionosphere are comparable to those resulted from the height‐integrated one, where fine vertical structures of the ionospheric density and magnetic field perturbations are well resolved in the former. The present result confirms validity of the height‐integrated ionosphere model in the long parallel wavelength limit, as assumed in previous studies on the feedback instability.
Intraseasonal Variation of the Black Carbon Aerosol Concentration and Its Impact on Atmospheric Circulation Over the Southeastern Tibetan Plateau
Authors: Yang Jing , Wang Wei‐Chyung , Chen Guoxing , Bao Qing , Qi Xin , Zhou Siyuan
Published: September 2018

The black carbon (BC) concentration over the southeastern Tibetan Plateau is modulated by atmospheric intraseasonal variations and in turn affects atmospheric circulation through both direct radiative atmospheric warming and surface cooling. Based on an intraseasonal dry‐wet phase transition over the southeastern Tibetan Plateau, we investigated the short‐term radiative‐dynamic coupling of the atmosphere with changes in the concentration of BC using both observations and numerical sensitivity experiments. The observed local concentrations of BC increased by >50% as a result of the enhanced convergence and upward migration associated with the development of an intraseasonal anomalous lower‐level cyclone. Calculations using an offline radiation transfer model showed that this increase in BC concentration led to ~4 W/m2 of atmospheric radiative warming and ~2 W/m2 of surface radiative cooling. Consequently, an anomalous lower‐level cyclone with an average wind speed of 0.5 m/s (~10% of the natural change from a dry to a wet phase) developed in a linear baroclinic model and an aerosol‐aware WRF model, which was mainly a result of the atmospheric warming while the surface cooling played only a minor role. Although the change in precipitation was small, cloud fraction was significantly increased due to the enhanced upward motion in the atmosphere. This warrants further studies of cloud adjustments to the BC concentration on both cloud fraction and microphysics aspects. The present study illustrates that consideration of aerosol‐circulation coupling is imperative to advance the subseasonal prediction of atmospheric circulation.
Submarine Deposition of a Subaerial Landslide in Taan Fiord, Alaska
Authors: Haeussler P. J. , Gulick S. P. S. , McCall N. , Walton M. , Reece R. , Larsen C. , Shugar D. H. , Geertsema M. , Venditti J. G. , Labay K.
Published: September 2018

A large subaerial landslide entered Taan Fiord, Alaska, on 17 October 2015 producing a tsunami with runup to 193 m. We use LiDAR data to show the slide volume to be 76 + 3/−4 million cubic meters and that 51,000,000 m3 entered Taan Fiord. In 2016, we mapped the fjord with multibeam bathymetry and high‐resolution seismic data. Landslide and postlandslide deposits extend 6 km downfjord, are up to 70 ± 11 m thick, and have a total volume of ~147,000,000 m3. Seismic data image a blocky landslide unit and two units deposited immediately after the landslide. The blocky landslide unit is ~65,000,000 m3. We infer it consists dominantly of subaerially derived material and secondarily of fjord floor sediment. The overlying units are likely megaturbidites presumably deposited within minutes to days after the landslide. We infer that these deposits dominantly consist of fjord floor material mobilized and suspended as the slide entered and traveled downfjord. The lower postlandslide unit is up to 35 ± 6 m thick, and the upper unit is up to 12 ± 3 m thick. These deposits are distinctive and will leave a lasting record of the event. This subaerial‐to‐submarine landslide deposit is distinct from other submarine landslide deposits studied in Alaskan fjords because it has a much greater thickness, larger and more angular blocks, distinctive postlandslide megaturbidites, and a higher‐amplitude acoustic signature of the blocky deposit. The tight constraints on the landslide source and deposit volumes, topography, bathymetry, and tsunami runup heights and flow directions should make this a benchmark site for landslide‐tsunami models.
Quantifying Bed Level Change at the Transition of Tidal Flat and Salt Marsh: Can We Understand the Lateral Location of the Marsh Edge?
Authors: Willemsen P. W. J. M. , Borsje B. W. , Hulscher S. J. M. H. , Van der Wal D. , Zhu Z. , Oteman B. , Evans B. , Möller I. , Bouma T. J.
Published: September 2018

Bed level dynamics at the interface of the salt marsh and tidal flat have been highlighted as a key factor connecting the long‐term biogeomorphological development of the marsh to large‐scale physical forcing. Hence, we aim to obtain insight into the factors confining the location of the marsh edge (i.e., boundary between tidal flat and salt marsh). A unique data set was collected, containing measurements of daily bed level changes (i.e., integrative result of physical forcing and sediment properties) at six intertidal transects in the North Sea area. Moreover, various biophysical parameters were measured, such as sediment characteristics, waves, inundation time, and chlorophyll‐a levels. The data show that both bed level change and waves decreased from the lower intertidal flat toward the marsh edge and further diminished inside the marsh. However, no direct general relation was found between waves and bed level change. Bed level change inside the marsh was always small, regardless of wave energy. By combining the data sets, we demonstrate that the location of the lower marsh edge is restricted by two interacting factors: inundation time and bed level change. For vegetation establishment to withstand longer inundation stress, which slows down plant growth, more stable bed levels are required so that plants are not heavily disturbed. Conversely, to withstand more dynamic bed levels that disturbs plant growth, lower inundation stress is needed, so that plants grow fast enough to recover from the stress. The results suggest that bed level change is important in determining the position of the marsh edge.
Biodegradability of Thermokarst Carbon in a Till‐Associated, Glacial Margin Landscape: The Case of the Peel Plateau, NWT, Canada
Authors: Littlefair Cara A. , Tank Suzanne E.
Published: September 2018

The Peel Plateau is a characteristic glacial margin landscape, with permafrost comprised of thick, ice‐rich glacial tills deposited at the end of the Last Glacial Maximum. Unmodified tills at depth are overlain by a paleo‐active layer, created when early Holocene warming deepened regional active layers, enabling organic matter incorporation into now‐frozen soils. Ice‐rich permafrost encourages retrogressive thaw slumps, which mobilize variable proportions of modern active layer, paleo‐active layer, and Pleistocene tills to downstream systems. Here we investigate the biolability of thaw‐released dissolved organic carbon (DOC) on the Peel Plateau and compare our results to previous studies from nontill‐dominated landscapes. Similar to other Arctic regions, biolability was significantly greater for slump‐derived DOC (retrogressive thaw slump runoff) than for DOC from paired, unimpacted locations. However, runoff source was an important control on biolability. Lability was greater for slumps releasing water with a Holocene‐like δ18O signature than for slumps with a more Pleistocene‐like signature, while a small slump, with runoff δ18O similar to the modern active layer, showed no biolability increase. Similar to other Arctic regions, biolability was strongly related to DOC aromaticity and molecular weight. However, lability also increased significantly with increasing nutrients, which has not been shown universally. Previous work has shown that DOC concentration dynamics differ sharply on the Peel Plateau when compared to other permafrost thaw landscapes. This work indicates that the lability of permafrost DOC may be relatively uniform across variable Arctic regions, although some factors—such as the importance of nutrient status—may need further exploration.
Cyclostratigraphy and Magnetostratigraphy of the Middle Miocene Ashigong Formation, Guide Basin, China, and Its Implications for the Paleoclimatic Evolution of NE Tibet
Authors: Wang Zhixiang , Shen Yongjin , Licht Alexis , Huang Chunju
Published: September 2018

Recent tectonostratigraphy studies have shown that Northeast Tibet underwent significant tectonic uplift and basin partitioning at 13–8 Ma. This time window is also a period of significant changes in Asian monsoonal intensity, mechanisms of which remain poorly understood. Though many studies have tried to decipher paleoclimatic trends from sedimentary archives in Northeast Tibetan basins, it is often hard to distinguish local orographic effects from regional climate changes in such a tectonically active context. Here we investigated the sedimentary record of the Ashigong Formation, Guide Basin, in order to better constrain the Tibetan paleoenvironmental evolution and link it to uplift episodes and monsoonal evolution. By studying the lithology, magnetostratigraphy, redness, magnetic susceptibility, and elemental content of a ~500‐m section, we show that the Ashigong Formation was deposited in a saline paleolake between 14.4 and 10 Ma. Lake expansion displayed cyclic variations following ~100‐kyr cycles and weaker ~41‐kyr cycles, reaching its maximum between ~11.4 and 10.5 Ma. Our results show that the Guide Basin was hydrologically closed from most of the middle Miocene, confirming previous studies that proposed an early Miocene partitioning of this basin. The maximum lake expansion between 11.4 and 10.5 Ma is coeval to a known peak of monsoonal intensity. This, and the evidence for a strong orbital control on lake expansion, supports a strong monsoonal control on the expansion of middle Miocene Tibet paleolakes. The origin of the ~100‐kyr forcing on monsoonal moisture supply—different from Quaternary forcing—questions the climatic mechanism of these middle Miocene monsoons and suggests that westerly derived moisture might have also significantly contributed to the regional hydrological budget.
Drought Conditions Maximize the Impact of High‐Frequency Flow Variations on Thermal Regimes and Biogeochemical Function in the Hyporheic Zone
Authors: Song Xuehang , Chen Xingyuan , Stegen James , Hammond Glenn , Song Hyun‐Seob , Dai Heng , Graham Emily , Zachara John M.
Published: September 2018

Anthropogenic activities, especially dam operations, often induce larger and more frequent stage fluctuations than those occurring in natural rivers. However, long‐term impacts of such flow variations on thermal and biogeochemical dynamics of the associated hyporheic zone (HZ) are poorly understood. In this study, we built a heterogeneous, two‐dimensional, thermo‐hydro‐biogeochemical model for an aerobic respiration dominated river system. Our results revealed important interactions between subdaily to weekly flow variations and mean flow conditions controlled by snowpack at the watershed. High‐frequency stage fluctuations had their strongest thermal and biogeochemical impacts when mean river stage was low during fall and winter. In an abnormal drought year (2015) with low river stages during summer and early fall, high‐frequency stage fluctuations caused the HZ to be warmer than average. Furthermore, high‐frequency stage fluctuation enhanced all biogeochemical reactions by increasing nutrient supply and creating more oxygenated conditions. Overall carbon consumption in the HZ increased due to high‐frequency flow variations. Thermal dynamics altered by high‐frequency stage fluctuation impacted biogeochemical reactions in the HZ less than effects imposed by enhanced nutrient and oxygen supply. In addition to these results, we demonstrated that the HZ's hydrogeologic properties control flow paths that influence residence times and nutrient supply and consequently control spatial distribution of biogeochemical reaction hot spots in the HZ. Here we provide scientific basis for assessing potential ecological consequences of high‐frequency flow variations in a regulated river, as well as guidance for maximizing potential benefits—or minimizing drawbacks—of dam regulation to riverine ecosystems.
Systemic signaling contributes to the unfolded protein response of the plant endoplasmic reticulum
Authors: Lai Ya-Shiuan , Stefano Giovanni , Zemelis-Durfee Starla , Ruberti Cristina , Gibbons Lizzie , Brandizzi Federica
Published: September 2018

The unfolded protein response (UPR) of the endoplasmic reticulum constitutes a conserved and essential cytoprotective pathway designed to survive biotic and abiotic stresses that alter the proteostasis of the endoplasmic reticulum. The UPR is typically considered cell-autonomous and it is yet unclear whether it can also act systemically through non-cell autonomous signaling. We have addressed this question using a genetic approach coupled with micro-grafting and a suite of molecular reporters in the model plant species Arabidopsis thaliana. We show that the UPR has a non-cell autonomous component, and we demonstrate that this is partially mediated by the intercellular movement of the UPR transcription factor bZIP60 facilitating systemic UPR signaling. Therefore, in multicellular eukaryotes such as plants, non-cell autonomous UPR signaling relies on the systemic movement of at least a UPR transcriptional modulator.
One-step generation of multiple gene knock-outs in the diatom Phaeodactylum tricornutum by DNA-free genome editing
Authors: Serif Manuel , Dubois Gwendoline , Finoux Anne-Laure , Teste Marie-Ange , Jallet Denis , Daboussi Fayza
Published: September 2018

Recently developed transgenic techniques to explore and exploit the metabolic potential of microalgae present several drawbacks associated with the delivery of exogenous DNA into the cells and its subsequent integration at random sites within the genome. Here, we report a highly efficient multiplex genome-editing method in the diatom Phaeodactylum tricornutum, relying on the biolistic delivery of CRISPR-Cas9 ribonucleoproteins coupled with the identification of two endogenous counter-selectable markers, PtUMPS and PtAPT. First, we demonstrate the functionality of RNP delivery by positively selecting the disruption of each of these genes. Then, we illustrate the potential of the approach for multiplexing by generating double-gene knock-out strains, with 65% to 100% efficiency, using RNPs targeting one of these markers and PtAureo1a, a photoreceptor-encoding gene. Finally, we created triple knock-out strains in one step by delivering six RNP complexes into Phaeodactylum cells. This approach could readily be applied to other hard-to-transfect organisms of biotechnological interest.
RNA editing derived epitopes function as cancer antigens to elicit immune responses
Authors: Zhang Minying , Fritsche Jens , Roszik Jason , Williams Leila J. , Peng Xinxin , Chiu Yulun , Tsou Chih-Chiang , Hoffgaard Franziska , Goldfinger Valentina , Schoor Oliver , Talukder Amjad , Forget Marie A. , Haymaker Cara , Bernatchez Chantale , Han Leng , Tsang Yiu-Huen , Kong Kathleen , Xu Xiaoyan , Scott Kenneth L. , Singh-Jasuja Harpreet , Lizee Greg , Liang Han , Weinschenk Toni , Mills Gordon B. , Hwu Patrick
Published: September 2018

In addition to genomic mutations, RNA editing is another major mechanism creating sequence variations in proteins by introducing nucleotide changes in mRNA sequences. Deregulated RNA editing contributes to different types of human diseases, including cancers. Here we report that peptides generated as a consequence of RNA editing are indeed naturally presented by human leukocyte antigen (HLA) molecules. We provide evidence that effector CD8+ T cells specific for edited peptides derived from cyclin I are present in human tumours and attack tumour cells that are presenting these epitopes. We show that subpopulations of cancer patients have increased peptide levels and that levels of edited RNA correlate with peptide copy numbers. These findings demonstrate that RNA editing extends the classes of HLA presented self-antigens and that these antigens can be recognised by the immune system.
A germanium hole spin qubit
Authors: Watzinger Hannes , Kukučka Josip , Vukušić Lada , Gao Fei , Wang Ting , Schäffler Friedrich , Zhang Jian-Jun , Katsaros Georgios
Published: September 2018

Holes confined in quantum dots have gained considerable interest in the past few years due to their potential as spin qubits. Here we demonstrate two-axis control of a spin 3/2 qubit in natural Ge. The qubit is formed in a hut wire double quantum dot device. The Pauli spin blockade principle allowed us to demonstrate electric dipole spin resonance by applying a radio frequency electric field to one of the electrodes defining the double quantum dot. Coherent hole spin oscillations with Rabi frequencies reaching 140 MHz are demonstrated and dephasing times of 130 ns are measured. The reported results emphasize the potential of Ge as a platform for fast and electrically tunable hole spin qubit devices.
EPR Imaging of Metallic Lithium and its Application to Dendrite Localisation in Battery Separators
Authors: Niemöller Arvid , Jakes Peter , Eichel Rüdiger-A. , Granwehr Josef
Published: September 2018

Conduction Electron Paramagnetic Resonance Imaging (CEPRI) is presented as a sensitive technique for mapping metallic lithium species. The method is demonstrated using different samples that are either thick or thin compared to the microwave skin depth. As a thin sample, microstructured metallic lithium deposits in a lithium-ion battery (LIB) separator were analysed, illustrating the capabilities of CEPRI by obtaining a high-resolution image with an image resolution in the micrometre range. Limitations and intricacies of the method due to non-linear effects caused by the skin effect are discussed based on images of surface patterns on thick metallic lithium samples. The lineshape of the EPR spectrum is introduced as a proxy to determine the suitability of CEPRI for the quantitative visualisation of metallic lithium deposits. The results suggest that CEPRI is particularly suited to analyse the spatial distribution of microstructured Li that forms during charging and discharging of LIB cells, including the localization of the point of failure in the case of an internal cell short circuit caused by dendrites.
Protein Profile of Blood Monocytes is Altered in HTLV-1 Infected Patients: Implications for HAM/TSP Disease
Authors: Echevarria-Lima Juliana , de Abreu Pereira Denise , de Oliveira Thais Silva , de Melo Espíndola Otávio , Lima Marco Antonio , Celestino Leite Ana Cláudia , Sandim Vanessa , Rodrigues Nascimento Clarissa , E. Kalume Dario , B. Zingali Russolina
Published: September 2018

Human T-cell lymphotropic virus type-1 (HTLV-1) is the etiological agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The endothelial breakdown and migration of leukocytes, including monocytes, to the spinal cord are involved in HAM/TSP development. Monocytes from HTLV-1-infected individuals exhibit important functional differences when compared to cells from uninfected donors. Using proteomic shot gun strategy, performed by nanoACQUITY-UPLC system, we analyzed monocytes isolated from peripheral blood of asymptomatic carriers (AC), HAM/TSP and uninfected individuals. 534 proteins were identified among which 376 were quantified by ExpressionEsoftware. Our study revealed a panel of changes in protein expression linked to HTLV-1 infection. Upregulation of heat shock proteins and downregulation of canonical histone expression were observed in monocytes from HTLV-1-infected patients. Moreover, expression of cytoskeleton proteins was increased in monocytes from HTLV-1-infected patients, mainly in those from HAM/TSP, which was confirmed by flow cytometry and fluorescence microscopy. Importantly, functional assays demonstrated that monocytes from HAM/TSP patients present higher ability for adhesion and transmigration thought endothelium than those from AC and uninfected individuals. The major changes on monocyte protein profile were detected in HAM/TSP patients, suggesting that these alterations exert a relevant role in the establishment of HAM/TSP.
Formation of hybrid higher-order cylindrical vector beams using binary multi-sector phase plates
Authors: Khonina Svetlana N. , Ustinov Andrey V. , Fomchenkov Sergey A. , Porfirev Alexey P.
Published: September 2018

Nowadays, the well-known cylindrical vector beams (CVBs) – the axially symmetric beam solution to the full-vector electromagnetic wave equation – are widely used for advanced laser material processing, optical manipulation and communication and have a great interest for data storage. Higher-order CVBs with polarisation order greater than one and superpositions of CVBs of various orders (hybrid CVBs) are especially of interest because of their great potential in contemporary optics. We performed a theoretical analysis of the transformation of first-order CVBs (radially and azimuthally polarised beams) into hybrid higher-order ones using phase elements with complex transmission functions in the form of the cosine or sine functions of the azimuthal angle. Binary multi-sector phase plates approximating such transmission functions were fabricated and experimentally investigated. The influence of the number of sectors and a height difference between neighbouring sectors, as well as the energy contribution of the different components in the generated hybrid higher-order CVBs were discussed in the context of polarisation transformation and vector optical field transformation in the focal region. The possibility of polarisation transformation, even in the case of weak focusing, is also demonstrated. The simple structure of the profile of such plates, their high diffraction efficiency and high damage threshold, as well as the easy-to-implement polarisation transformation principle provide advanced opportunities for high-efficient, quickly-switchable dynamic control of the generation of structured laser beams.
Tetrahydrobiopterin modulates ubiquitin conjugation to UBC13/UBE2N and proteasome activity by S-nitrosation
Authors: Bailey Jade , Davis Simon , Shaw Andrew , Diotallevi Marina , Fischer Roman , Benson Matthew A. , Zhu Hanneng , Brown James , Bhattacharya Shoumo , Kessler Benedikt M. , Channon Keith M. , Crabtree Mark J.
Published: September 2018

Nitric Oxide (NO) is an intracellular signalling mediator, which affects many biological processes via the posttranslational modification of proteins through S-nitrosation. The availability of NO and NOS-derived reactive oxygen species (ROS) from enzymatic uncoupling are determined by the NO synthase cofactor Tetrahydrobiopterin (BH4). Here, using a global proteomics “biotin-switch” approach, we identified components of the ubiquitin-proteasome system to be altered via BH4-dependent NO signalling by protein S-nitrosation. We show S-nitrosation of ubiquitin conjugating E2 enzymes, in particular the catalytic residue C87 of UBC13/UBE2N, leading to impaired polyubiquitylation by interfering with the formation of UBC13~Ub thioester intermediates. In addition, proteasome cleavage activity in cells also seems to be altered by S-nitrosation, correlating with the modification of cysteine residues within the 19S regulatory particle and catalytic subunits of the 20S complex. Our results highlight the widespread impact of BH4 on downstream cellular signalling as evidenced by the effect of a perturbed BH4-dependent NO-Redox balance on critical processes within the ubiquitin-proteasome system (UPS). These studies thereby uncover a novel aspect of NO associated modulation of cellular homeostasis.
Eating fast is positively associated with general and abdominal obesity among Chinese children: A national survey
Authors: Zeng Xia , Cai Li , Ma Jun , Ma Yinghua , Jing Jin , Chen Yajun
Published: September 2018

Eating faster is related to more energy intake, but less is known about the relationships between children’s eating speed, food intake and adiposity, especially in high school children. This study aimed to investigate the associations of eating speed with general and abdominal obesity among Chinese children basing on a national survey. A total of 50,037 children aged 7–17 years were enrolled from 7 provinces in China in 2013. Anthropometric indices were objectively measured. Data on eating speed were collected by questionnaires. Increasing trends across the slow, medium, and fast eating speed group were observed in the prevalence of general obesity (7.2%, 10.0% and 15.9%), abdominal obesity (16.1%, 21.8%, and 29.4%) and waist-to-height ratio (WHtR) ≥ 0.5 (11.1%, 14.8%, and 22.0%). Compared with medium eating speed, fast eating speed was positively associated with obesity, abdominal obesity, and WHtR ≥ 0.5 (odds ratios [ORs]: 1.51~1.61), while slow eating speed was negatively associated with these outcomes (ORs: 0.65~0.75). Increased trends of consumption of fruits, meat/meat conducts, sugar-sweetened beverages, fried food, and fast food were observed in pace with increasing eating speed (P < 0.05). Our findings suggest that eating speed is positively associated with childhood general and abdominal obesity, which may be an important, modifiable factor to prevent childhood obesity.
The effect of oscillator and dipole-dipole interaction on multiple optomechanically induced transparency in cavity optomechanical system
Authors: Ma Jin-Lou , Tan Lei , Li Qing , Gu Huai-Qiang , Liu Wu-Ming
Published: September 2018

We theoretically investigate the optomechanically induced transparency (OMIT) phenomenon in a N-cavity optomechanical system doped with a pair of Rydberg atoms with the presence of a strong control field and a weak probe field applied to the Nth cavity. It is found that 2N − 1 (N < 10) numbers of OMIT windows can be observed in the output field when N cavities couple with N mechanical oscillators and the mechanical oscillators coupled with different even- or odd-labelled cavities can lead to diverse effects on OMIT. Furthermore, the ATS effect appears with the increase of the effective optomechanical coupling rate. On the other hand, two additional transparent windows (extra resonances) occur, when two Rydberg atoms are coupled with the cavity field. With DDI strength increasing, the extra resonances move to the far off-resonant regime but the left one moves slowly than the right one due to the positive detuning effect of DDI. During this process, Fano resonance also emerges in the absorption profile of output field.
Comparative in depth RNA sequencing of P. tricornutum’s morphotypes reveals specific features of the oval morphotype
Authors: Ovide Clément , Kiefer-Meyer Marie-Christine , Bérard Caroline , Vergne Nicolas , Lecroq Thierry , Plasson Carole , Burel Carole , Bernard Sophie , Driouich Azeddine , Lerouge Patrice , Tournier Isabelle , Dauchel Hélène , Bardor Muriel
Published: September 2018

Phaeodactylum tricornutumis the most studied diatom encountered principally in coastal unstable environments. It has been hypothesized that the great adaptability ofP.tricornutumis probably due to its pleomorphism. Indeed,P.tricornutumis an atypical diatom since it can display three morphotypes: fusiform, triradiate and oval. Currently, little information is available regarding the physiological significance of this morphogenesis. In this study, we adaptedP.tricornutumPt3 strain to obtain algal culture particularly enriched in one dominant morphotype: fusiform, triradiate or oval. These cultures were used to run high-throughput RNA-Sequencing. The whole mRNA transcriptome of each morphotype was determined. Pairwise comparisons highlighted biological processes and molecular functions which are up- and down-regulated. Finally, intersection analysis allowed us to identify the specific features from the oval morphotype which is of particular interest as it is often described to be more resistant to stresses. This study represent the first transcriptome wide characterization of the three morphotypes fromP.tricornutumperformed on cultures specifically enriched issued from the same Pt3 strain. This work represents an important step for the understanding of the morphogenesis inP.tricornutumand highlights the particular features of the oval morphotype.