bluuebunny/crossref_metadata_2025_split huggingface dataset:
Economic analysis of organic cropping systems under different tillage intensities and crop rotations
Authors: Dayananda Buwani , Fernandez Myriam R. , Lokuruge Prabhath , Zentner Robert P. , Schellenberg Michael P. 
Published: April 2021

AbstractCosts of production and organic price premiums are defining factors influencing the economic viability of organic crop production systems. Different agronomic practices, such as crop rotation and tillage intensity, are known to affect the economic performance of the production systems. The aim of this study was to compare the impact of two crop rotation sequences (simplified and diversified) and two levels of tillage intensity (high and low) on the cost of production, gross return and gross margin of crops when grown under organic management in the semi-arid Brown soil zone of the Canadian Prairies. The 2-year simplified rotation sequence consisted of forage pea (Pisum sativum L.) grown as a green manure followed by hard red spring wheat (HRSW) (Triticum aestivum L.), while the 4-year diversified rotation sequence was forage pea green manure followed by flax (Linum usitatissimum L.) or yellow mustard (Sinapis alba L.), field pea or lentil (Lens culinaris L.) and HRSW. Our hypothesis that a more diversified crop rotation would increase profitability over a traditional simplified crop rotation was supported by the findings. However, the findings did not support our hypothesis that reducing tillage intensity, and the combination of tillage reduction and diversified crop rotation through a synergetic response, would further enhance profitability. Analysis of the breakeven prices and breakeven yields for crops indicated the importance of adopting diversified crop rotations and choosing crops with high organic price premiums as means to maximize the long-term profitability of organic cropping systems.
Anthropogenic Warming and Population Growth May Double US Heat Stress by the Late 21st Century
Authors: Mukherjee Sourav , Mishra Ashok Kumar , Mann Michael E. , Raymond Colin 
Published: April 2021

AbstractGlobally, heat stress (HS) is nearly certain to increase rapidly over the coming decades, characterized by increased frequency, severity, and spatiotemporal extent of extreme temperature and humidity. While these characteristics have been investigated independently, a holistic analysis integrating them is potentially more informative. Using observations, climate projections from the CMIP5 model ensemble, and historical and future population estimates, we apply the IPCC risk framework to examine present and projected future potential impact (PI) of summer heat stress for the contiguous United States (CONUS) as a function of non‐stationary HS characteristics and population exposure. We find that the PI of short‐to‐medium duration (1–7 days) HS events is likely to increase more than three‐fold across densely populated regions of the U.S. including the Northeast, Southeast Piedmont, Midwest, and parts of the Desert Southwest by late this century (2060–2099) under the highest emissions scenario. The contribution from climate change alone more than doubles the impact in the coastal Pacific Northwest, central California, and the Great Lakes region, implying a substantial increase in HS risk without aggressive mitigation efforts.
Inland Tidal Oscillations Within the Yucatan Peninsula
Authors: Coutino Aaron , Stastna Marek , McNeill‐Jewer Chelsi , Reinhardt Eduard G. 
Published: April 2021

AbstractThe Yucatan Peninsula is composed of highly porous, karstified limestone, resulting in scarce surface water bodies. Portions of the peninsula have fracture zones throughout the subsurface. We present water level measurements from four inland locations, previously assumed to be hydrologically isolated from the regional aquifer, or at most leaky with a weak connection. At all locations, tidal oscillations were detected, and verified by performing significance testing. We argue that the presence of cave passages and fracture zones in the limestone allows for much further inland penetration of the tidal signal, compared to classical Richards equation based predictions. The analysis of lacustrine sediment‐based paleoclimate records from across the Yucatan Peninsula assumes low to no interchange between the water bodies and the aquifer, and this assumption may need to be revisited based on our results. Increased connectivity of aquifer to inland water bodies also suggests greater flood risk from sea level rise.
A Rocket‐Triggered Lightning Flash Containing Negative‐Positive‐Negative Current Polarity Reversal During Its Initial Stage
Authors: Li Fengquan , Sun Zhuling , Jiang Rubin , Tang Guoying , Liu Mingyuan , Li Xiao , Zhang Hongbo , Yuan Shanfeng , Tian Ye , Qie Xiushu 
Published: April 2021

AbstractA rocket‐triggered lightning flash containing negative‐positive‐negative current polarity reversal during its initial stage is analyzed using multiple synchronized observation data. The flash was triggered under a thunderstorm transition zone between the convective region and the stratiform region. The upward positive leader branched and developed toward the stratiform region. When the negative initial continuous current was decreasing, a negative stepped leader was transformed from a recoil leader on a preexisting positive branch. As the negative leader developed toward the convective region, a breakdown process initiated on a preexisting positive channel and propagated toward the back end of the negative stepped leader, accompanied with a positive electric field change pulse. The current polarity changed from negative to positive about 0.22 ms after the onset of the breakdown process. The negative leader terminated after propagating for 71.08 ms, while scattered discharges on other positive branches maintained to develop, and then the ICC polarity changed from positive to negative.
Hot Air, Hot Lakes, or Both? Exploring Mid‐Holocene African Temperatures Using Proxy System Modeling
Authors: Dee Sylvia G. , Morrill Carrie , Kim Seung Hye , Russell James M. 
Published: April 2021

AbstractClimate models predict Africa will warm by up to 5°C in the coming century, stressing African societies. To provide independent constraints on model predictions, this study compares two notable reconstructions of East African temperatures to those predicted by Paleoclimate Model Intercomparison Project (PMIP3) and transient TraCE (Transient Climate Evolution) simulations, focusing on the Mid‐Holocene (MH, 5–8 kyr B.P.). Reconstructions of tropical African temperature derived from lake sedimentary archives indicate 1–2.5°C of warming during the MH relative to the 20th century, but most climate models do not replicate the warming observed in these paleoclimate data. We investigate this discrepancy using a new lake proxy system model, with attention to the (potentially non‐stationary) relationship between lake temperature and air temperature. We find amplified lake surface temperature changes compared to air temperature during the MH due to heightened seasonality and precessional forcing. Lacustrine processes account for some of the warming, and highlight how the lake heat budget leads to a rectification of the seasonal cycle; however, the simulated lake heating bias is insufficient to reconcile the full discrepancy between the models and the proxy‐derived MH warming. We find further evidence of changes in mixing depth over time, potentially driven by changes in cloud cover and shortwave radiative fluxes penetrating the lake surface. This may confound interpretation for glycerol dialkyl glycerol tetraethers (GDGT) compounds which exist in the mixed layer, and suggests a need for independent constraints on mixed layer depth. This work provides a new interpretive framework for invaluable paleoclimate records of temperature changes over the African continent.
Significant Contribution of Severe Ozone Loss to the Siberian‐Arctic Surface Warming in Spring 2020
Authors: Xia Yan , Hu Yongyun , Huang Yi , Zhao Chuanfeng , Xie Fei , Yang Yikun 
Published: April 2021

AbstractSevere ozone loss and significant surface warming anomalies in the Siberian Arctic were observed in spring 2020. Here, we show that the anomalous surface warming was likely related to the ozone loss. The dramatic Arctic ozone loss in March was shifted to Siberia in April and May, which largely cools the lower stratosphere and leads to an increase of high clouds by modifying the static stability in the upper troposphere. This further results in an increase of longwave radiation at surface which likely contributes to surface warming. Multiple linear regression demonstrates that ozone loss contributes most of the surface warming in April, while the Arctic Oscillation and ice‐albedo feedback play a minor role. In May, both ozone loss and ice‐albedo feedback contribute to the surface warming. These results support that surface warming in the Siberian Arctic could occur in April and May when severe ozone loss occurs in March.
Estimation of Water Surface Energy Partitioning With a Conceptual Atmospheric Boundary Layer Model
Authors: Liu Ziwei , Yang Hanbo 
Published: April 2021

AbstractOpen water surface evaporation (E) or the latent heat flux (λE) is of great importance to surface water and energy budget. However, partitioning of the available energy into sensible heat flux (H) and λE, quantified as the Bowen ratio (), is implicitly discrepant between models and observations. In this study, an explicit equation for the estimation of Bo (thus for the λE) is derived based on an atmospheric boundary layer model combined with the potential vapor pressure deficit budget. Derived equation only requires the air temperature (Ta) and specific humidity (Q) as inputs, and performs well in λE estimation with a relative error of <1% over observations of global sea and inland lake surfaces. More importantly, this equation clearly expresses the physical relationship between Bo and air temperature and humidity, thus revealing the mechanism of water surface energy partitioning in response to external environmental variables.
Chemical Gardens Under Mars Conditions: Imaging Chemical Garden Growth In Situ in an Environmental Scanning Electron Microscope
Authors: Sainz‐Díaz C. Ignacio , Escribano Bruno , Sánchez‐Almazo Isabel , Cartwright Julyan H. E. 
Published: April 2021

AbstractWe have performed and visualized chemical garden growth experiments directly in situ in an environmental scanning electron microscope. The microscope chamber simulates the surface of Mars. We demonstrate that chemical gardens can form under the conditions of temperature and pressure existing on Mars in the presence of liquid water, silicates, and metal salts. Using chemical gardens from aluminum salts, tubes were formed where the external surface is formed principally by silicate and the inner surface is predominantly aluminum oxide‐hydroxide. It should thus be expected that similar growths of metal salts may be found in geological explorations of water‐rich environments during the search for life on Mars.
A Foreshock Bubble Driven by an IMF Tangential Discontinuity: 3D Global Hybrid Simulation
Authors: Wang Chih‐Ping , Wang Xueyi , Liu Terry Z. , Lin Yu 
Published: April 2021

AbstractForeshock bubbles (FBs) have been observed upstream of solar wind tangential discontinuities (TDs). A hypothesized mechanism is that foreshock ions with gyroradii larger than the TD thickness may move to upstream side of TDs and generate FBs. In this study, we present the very first three‐dimensional global hybrid simulation of an FB driven by a TD. After the TD encounters the ion foreshock, plasma and magnetic field perturbations are generated upstream of the TD. These perturbations are characteristically consistent with the observed TD‐driven FBs, confirming that TDs can form FBs. We further analyze the initial perpendicular temperature increase initiating the FB and compare the temperature structure with that from tracing test‐particles in static TD electric and magnetic fields. The structure can be explained by the perpendicular velocity change of foreshock ions with large gyroradii as they encounter the magnetic field direction change across the TD, which supports the hypothesized mechanism.
Constraining Spectral Models of a Terrestrial Gamma‐Ray Flash From a Terrestrial Electron Beam Observation by the Atmosphere‐Space Interactions Monitor
Authors: Sarria D. , Østgaard N. , Kochkin P. , Lehtinen N. , Mezentsev A. , Marisaldi M. , Lindanger A. , Maiorana C. , Carlson B. E. , Neubert T. , Reglero V. , Ullaland K. , Yang S. , Genov G. , Qureshi B. H. , Budtz‐Jørgensen C. , Kuvvetli I. , Christiansen F. , Chanrion O. , Navarro‐González J. , Connel P. , Eyles C. 
Published: April 2021

AbstractTerrestrial Gamma ray Flashes (TGFs) are short flashes of high energy photons, produced by thunderstorms. When interacting with the atmosphere, they produce relativistic electrons and positrons, and a part gets bounded to geomagnetic field lines and travels large distances in space. This phenomenon is called a Terrestrial Electron Beam (TEB). The Atmosphere‐Space Interactions Monitor (ASIM) mounted on‐board the International Space Station detected a new TEB event on March 24, 2019, originating from the tropical cyclone Johanina. Using ASIM's low energy detector, the TEB energy spectrum is resolved down to 50 keV. We provide a method to constrain the TGF source spectrum based on the detected TEB spectrum. Applied to this event, it shows that only fully developed Relativistic Runaway Electron Avalanche spectra are compatible with the observation. More specifically, assuming a TGF spectrum , the compatible models have ϵ ≥ 6.5 MeV (E is the photon energy and ϵ is the cut‐off energy). We could not exclude models with ϵ of 8 and 10 MeV.
Higher gametocyte production and mosquito infectivity in chronic compared to incident Plasmodium falciparum infections
Authors: Barry Aissata , Bradley John , Stone Will , Guelbeogo Moussa W. , Lanke Kjerstin , Ouedraogo Alphonse , Soulama Issiaka , Nébié Issa , Serme Samuel S. , Grignard Lynn , Patterson Catriona , Wu Lindsey , Briggs Jessica J. , Janson Owen , Awandu Shehu S. , Ouedraogo Mireille , Tarama Casimire W. , Kargougou Désiré , Zongo Soumanaba , Sirima Sodiomon B. , Marti Matthias , Drakeley Chris , Tiono Alfred B. , Bousema Teun 
Published: April 2021

AbstractPlasmodium falciparum gametocyte kinetics and infectivity may differ between chronic and incident infections. In the current study, we assess parasite kinetics and infectivity to mosquitoes among children (aged 5–10 years) from Burkina Faso with (a) incident infections following parasite clearance (n = 48) and (b) chronic asymptomatic infections (n = 60). In the incident infection cohort, 92% (44/48) of children develop symptoms within 35 days, compared to 23% (14/60) in the chronic cohort. All individuals with chronic infection carried gametocytes or developed them during follow-up, whereas only 35% (17/48) in the incident cohort produce gametocytes before becoming symptomatic and receiving treatment. Parasite multiplication rate (PMR) and the relative abundance of ap2-g and gexp-5 transcripts are positively associated with gametocyte production. Antibody responses are higher and PMR lower in chronic infections. The presence of symptoms and sexual stage immune responses are associated with reductions in gametocyte infectivity to mosquitoes. We observe that most incident infections require treatment before the density of mature gametocytes is sufficient to infect mosquitoes. In contrast, chronic, asymptomatic infections represent a significant source of mosquito infections. Our observations support the notion that malaria transmission reduction may be expedited by enhanced case management, involving both symptom-screening and infection detection.
PAX8 and MECOM are interaction partners driving ovarian cancer
Authors: Bleu Melusine , Mermet-Meillon Fanny , Apfel Verena , Barys Louise , Holzer Laura , Bachmann Salvy Marianne , Lopes Rui , Amorim Monteiro Barbosa Inês , Delmas Cecile , Hinniger Alexandra , Chau Suzanne , Kaufmann Markus , Haenni Simon , Berneiser Karolin , Wahle Maria , Moravec Ivana , Vissières Alexandra , Poetsch Tania , Ahrné Erik , Carte Nathalie , Voshol Johannes , Bechter Elisabeth , Hamon Jacques , Meyerhofer Marco , Erdmann Dirk , Fischer Matteo , Stachyra Therese , Freuler Felix , Gutmann Sascha , Fernández César , Schmelzle Tobias , Naumann Ulrike , Roma Guglielmo , Lawrenson Kate , Nieto-Oberhuber Cristina , Cobos-Correa Amanda , Ferretti Stephane , Schübeler Dirk , Galli Giorgio Giacomo 
Published: April 2021

AbstractThe transcription factor PAX8 is critical for the development of the thyroid and urogenital system. Comprehensive genomic screens furthermore indicate an additional oncogenic role for PAX8 in renal and ovarian cancers. While a plethora of PAX8-regulated genes in different contexts have been proposed, we still lack a mechanistic understanding of how PAX8 engages molecular complexes to drive disease-relevant oncogenic transcriptional programs. Here we show that protein isoforms originating from the MECOM locus form a complex with PAX8. These include MDS1-EVI1 (also called PRDM3) for which we map its interaction with PAX8 in vitro and in vivo. We show that PAX8 binds a large number of genomic sites and forms transcriptional hubs. At a subset of these, PAX8 together with PRDM3 regulates a specific gene expression module involved in adhesion and extracellular matrix. This gene module correlates with PAX8 and MECOM expression in large scale profiling of cell lines, patient-derived xenografts (PDXs) and clinical cases and stratifies gynecological cancer cases with worse prognosis. PRDM3 is amplified in ovarian cancers and we show that the MECOM locus and PAX8 sustain in vivo tumor growth, further supporting that the identified function of the MECOM locus underlies PAX8-driven oncogenic functions in ovarian cancer.
Spontaneous nucleation on flat surface by depletion force in colloidal suspension
Authors: Nakamura Nobutomo , Sakamoto Yuto , Ogi Hirotsugu 
Published: April 2021

AbstractNucleation by sedimentation of colloidal particles on a flat surface is experimentally observed, and effect of attractive depletion force generated by polymers on nucleation is investigated. Sedimentation forms polycrystalline colloidal crystal on a flat surface, and above the threshold polymer concentration, ratio of the spontaneous nucleation increases, resulting in a decrease in the grain size, whereas dependence of the contact angle on the polymer concentration was not observed. We show that the interaction between particles and the flat surface mainly affects the spontaneous nucleation, not the interaction between the particles, and it is demonstrated that the nucleation process can be numerically reproduced using the rate equations.
Associations between green/blue spaces and mental health across 18 countries
Authors: White Mathew P. , Elliott Lewis R. , Grellier James , Economou Theo , Bell Simon , Bratman Gregory N. , Cirach Marta , Gascon Mireia , Lima Maria L. , Lõhmus Mare , Nieuwenhuijsen Mark , Ojala Ann , Roiko Anne , Schultz P. Wesley , van den Bosch Matilda , Fleming Lora E. 
Published: April 2021

AbstractLiving near, recreating in, and feeling psychologically connected to, the natural world are all associated with better mental health, but many exposure-related questions remain. Using data from an 18-country survey (n = 16,307) we explored associations between multiple measures of mental health (positive well-being, mental distress, depression/anxiety medication use) and: (a) exposures (residential/recreational visits) to different natural settings (green/inland-blue/coastal-blue spaces); and (b) nature connectedness, across season and country. People who lived in greener/coastal neighbourhoods reported higher positive well-being, but this association largely disappeared when recreational visits were controlled for. Frequency of recreational visits to green, inland-blue, and coastal-blue spaces in the last 4 weeks were all positively associated with positive well-being and negatively associated with mental distress. Associations with green space visits were relatively consistent across seasons and countries but associations with blue space visits showed greater heterogeneity. Nature connectedness was also positively associated with positive well-being and negatively associated with mental distress and was, along with green space visits, associated with a lower likelihood of using medication for depression. By contrast inland-blue space visits were associated with a greater likelihood of using anxiety medication. Results highlight the benefits of multi-exposure, multi-response, multi-country studies in exploring complexity in nature-health associations.
An examination of skeletal muscle and hepatic tissue transcriptomes from beef cattle divergent for residual feed intake
Authors: McKenna Clare , Keogh Kate , Porter Richard K. , Waters Sinead M. , Cormican Paul , Kenny David A. 
Published: April 2021

AbstractThe selection of cattle with enhanced feed efficiency is of importance with regard to reducing feed costs in the beef industry. Global transcriptome profiling was undertaken on liver and skeletal muscle biopsies from Simmental heifers and bulls divergent for residual feed intake (RFI), a widely acknowledged feed efficiency phenotype, in order to identify genes that may be associated with this trait. We identified 5 genes (adj. p < 0.1) to be differentially expressed in skeletal muscle between high and low RFI heifers with all transcripts involved in oxidative phosphorylation and mitochondrial homeostasis. A total of 11 genes (adj. p < 0. 1) were differentially expressed in liver tissue between high and low RFI bulls with differentially expressed genes related to amino and nucleotide metabolism as well as endoplasmic reticulum protein processing. No genes were identified as differentially expressed in either heifer liver or bull muscle analyses. Results from this study show that the molecular control of RFI in young cattle is modified according to gender, which may be attributable to differences in physiological maturity between heifers and bulls of the same age. Despite this we have highlighted a number of genes that may hold potential as molecular biomarkers for RFI cattle.
Functional modulation of phosphodiesterase-6 by calcium in mouse rod photoreceptors
Authors: Turunen Teemu , Koskelainen Ari 
Published: April 2021

AbstractPhosphodiesterase-6 (PDE6) is a key protein in the G-protein cascade converting photon information to bioelectrical signals in vertebrate photoreceptor cells. Here, we demonstrate that PDE6 is regulated by calcium, contrary to the common view that PDE1 is the unique PDE class whose activity is modulated by intracellular Ca2+. To broaden the operating range of photoreceptors, mammalian rod photoresponse recovery is accelerated mainly by two calcium sensor proteins: recoverin, modulating the lifetime of activated rhodopsin, and guanylate cyclase-activating proteins (GCAPs), regulating the cGMP synthesis. We found that decreasing rod intracellular Ca2+ concentration accelerates the flash response recovery and increases the basal PDE6 activity (βdark) maximally by ~ 30% when recording local electroretinography across the rod outer segment layer from GCAPs−/− recoverin−/− mice. Our modeling shows that a similar elevation in βdark can fully explain the observed acceleration of flash response recovery in low Ca2+. Additionally, a reduction of the free Ca2+ in GCAPs−/− recoverin−/− rods shifted the inhibition constants of competitive PDE inhibitor 3-isobutyl-1-methylxanthine (IBMX) against the thermally activated and light-activated forms of PDE6 to opposite directions, indicating a complex interaction between IBMX, PDE6, and calcium. The discovered regulation of PDE6 is a previously unknown mechanism in the Ca2+-mediated modulation of rod light sensitivity.