229 research outputs found

    Monitoring Stormwater Redistribution Into Low Resistivity Soils Using Noninvasive Geophysical Techniques

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    Water held in the unsaturated zone is important for agriculture and construction and is replenished by infiltrating rainwater. Monitoring the soil water content of clay soils using ground-penetrating radar (GPR) has not been researched, as clay soils cause attenuation of GPR signal. In this study, GPR common-midpoint soundings (CMPs) are used in the clayey soils of the Miller Run floodplain to monitor changes in the soil water content (SWC) before and after rainfall events. GPR accomplishes this task because increases in water content will increase the dielectric constant of the subsurface material, and decrease the velocity of the GPR wave. Using an empirical relationship between dielectric constant and SWC, the Topp relation, we are able to calculate a SWC from these velocity measurements. Non-invasive electromagnetics, resistivity, and seismic were performed, and from these surveys, the layering at the field site was delineated. EM characterized the horizontal variation of the soil, allowing us to target the most clay rich area. At the CMP location, resistivity indicates the vertical structure of the subsurface consists of a 40 cm thick layer with a resistivity of 100 ohm*m. Between 40 cm and 1.5 m is a layer with a resistivity of 40 ohm*m. The thickness estimates were confirmed with invasive auger and trenching methods away from the CMP location. GPR CMPs were collected relative to a July 2013 and September 2013 storm. The velocity observations from the CMPs had a precision of +/- 0.001 m/ns as assessed by repeat analysis. In the case of both storms, the GPR data showed the expected relationship between the rainstorms and calculated SWC, with the SWC increasing sharply after the rainstorm and decreasing as time passed. We compared these data to auger core samples collected at the same time as the CMPs were taken, and the volumetric analysis of the cores confirmed the trend seen in the GPR, with SWC values between 3 and 5 percent lower than the GPR estimates. Our data shows that we can, with good precision, monitor changes in the SWC of conductive soils in response to rainfall events, despite the attenuation induced by the clay

    Interacting two-level defects as sources of fluctuating high-frequency noise in superconducting circuits

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    Since the very first experiments, superconducting circuits have suffered from strong coupling to environmental noise, destroying quantum coherence and degrading performance. In state-of-the-art experiments, it is found that the relaxation time of superconducting qubits fluctuates as a function of time. We present measurements of such fluctuations in a 3D-transmon circuit and develop a qualitative model based on interactions within a bath of background two-level systems (TLS) which emerge from defects in the device material. In our model, the time-dependent noise density acting on the qubit emerges from its near-resonant coupling to high-frequency TLS which experience energy fluctuations due to their interaction with thermally fluctuating TLS at low frequencies. We support the model by providing experimental evidence of such energy fluctuations observed in a single TLS in a phase qubit circuit

    UmweltfördermaÃƞnahmen in der Landwirtschaft – Teilnehmerauswahl durch Ausschreibungen?

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    Agri-environmental programs offering uniform payments to farmers achieved only low participation ratios in some regions whereas, in other regions, windfall profits arose. Auctions leading to individual payments equal to farmers’ bids could solve this problem. Simulations showing auctions’ efficiency gains are based on critical assumptions though. In this article the validity of these assumptions is discussed for different auction designs and different subprograms. We find that extensification programs offer the best conditions for successful auctions. However, it seems counterproductive to use auctions for choosing among different areas in environmental contracting.agri-environmental measures, auctions, efficiency, Agricultural and Food Policy, Environmental Economics and Policy,

    What are the effects of climate change on agriculture in North East Central Europe?

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    Global and climate changes influence the basic conditions for agriculture and so there is not only a demand for a consequent climate protection but also for an adaptation of agriculture to these global changing conditions. For the whole "Maerkisch-Oderland" district (60x40 km) within the moraine landscape of North-East-Germany mainly used for agriculture water balance, nitrogen and sulphur loads as well as crop yields are calculated for two land use and climate scenarios. The comparison between the Scenario2050 and the Scenario2000 reveals significant changes of the water balance (decrease in percolation water, increase in actual evapotranspiration) as well as the concentration of the examined nitrogen in the percolation water. For the study region the crop yields decrease only slightly if the CO2 fertilizing effect is taken into account. Adaptation measures in reaction to the changing climate conditions for an economically secured and sustainable agriculture are recommended.climate change impact assessment, water balance, nitrogen load, crop yield, moraine landscape, Environmental Economics and Policy, Farm Management,

    Cardio-Respiratory Coordination Increases during Sleep Apnea

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    Funding: MR, NW, AM, TP and JK acknowledge financial support from RI2916/2-1, WE2834/5-1, PE628/4-1, and KU837/23-1 (Deutsche Forschungsgemeinschaft). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Warm and Dense Molecular Gas in the N159 Region: 12CO J=4-3 and 13CO J=3-2 Observations with NANTEN2 and ASTE

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    New 12CO J=4-3 and 13CO J=3-2 observations of the N159 region in the Large Magellanic Cloud have been made. The 12CO J=4-3 distribution is separated into three clumps. These new measurements toward the three clumps are used in coupled calculations of molecular rotational excitation and line radiation transfer, along with other transitions of the 12CO as well as the isotope transitions of 13CO. The temperatures and densities are determined to be ~70-80K and ~3x10^3 cm-3 in N159W and N159E and ~30K and ~1.6x10^3 cm-3 in N159S. These results are compared with the star formation activity. The N159E clump is associated with embedded cluster(s) as observed at 24 micron and the derived high temperature is explained as due to the heating by these sources. The N159E clump is likely responsible for a dark lane in a large HII region by the dust extinction. The N159W clump is associated with embedded clusters mainly toward the eastern edge of the clump only. These clusters show offsets of 20"-40" from the 12CO J=4-3 peak and are probably responsible for heating indicated by the derived high temperature. The N159W clump exhibits no sign of star formation toward the 12CO J=4-3 peak position and its western region. We suggest that the N159W peak represents a pre-star-cluster core of ~105M_sol which deserves further detailed studies. Note that recent star formation took place between N159W and N159E as indicated by several star clusters and HII regions, while the natal molecular gas toward the stars have already been dissipated by the ionization and stellar winds of the OB stars. The N159S clump shows little sign of star formation as is consistent with the lower temperature and somewhat lower density. The N159S clump is also a candidate for future star formation

    Seminal lipid profiling and antioxidant capacity : a species comparison

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    On their way to the oocyte, sperm cells are subjected to oxidative stress, which may trigger the oxidation of phospholipids (PL). Applying MALDI-TOF MS, HPTLC and ESI-IT MS, we comparatively analyzed the PL compositions of semen and blood of species differing in their reproductive systems and types of nutrition (bull, boar, stallion, lion and man) with regard to the sensitivity to oxidation as well as the accumulation of harmful lyso-PL (LPL), transient products of lipid oxidation. In addition, the protective capacity of seminal fluid (SF) was also examined. The PL composition of erythrocytes and blood plasma is similar across the species, while pronounced differences exist for sperm and SF. Since the blood function is largely conserved across mammalian species, but the reproductive systems may vary in many aspects, the obtained results suggest that the PL composition is not determined by the type of nutrition, but by the relatedness of species and by functional requirements of cell membranes such as fluidity. Sperm motion and fertilization of oocytes require a rather flexible membrane, which is accomplished by significant moieties of unsaturated fatty acyl residues in sperm lipids of most species, but implies a higher risk of oxidation. Due to a high content of plasmalogens (alkenyl ether lipids), bull sperm are most susceptible to oxidation. Our data indicate that bull sperm possess the most effective protective power in SF. Obviously, a co-evolution of PL composition and protective mechanisms has occurred in semen and is related to the reproductive characteristics. Although the protective capacity in human SF seems well developed, we recorded the most pronounced individual contaminations with LPL in human semen. Probably, massive oxidative challenges related to lifestyle factors interfere with natural conditions.SUPPLEMENTARY MATERIAL: S1 Fig. ESI spectra of lysophosphatidylcholine (LPC) fractions from boar, bull, stallion, lion and human samples.S2 Fig. ESI spectra of sphingomyelin (SM) fractions from boar, bull, stallion, lion and human samples. Lipid extracts were separated on a normal phase high performance thin-layer chromatography (HPTLC) plate with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). Lipids were made visible under UV light and marked with a pencil. SM fractions were directly analyzed by coupling a TLC plate reader to an ESI mass spectrometer. Mass spectra were recorded in the positive ion mode. For further details on ESI-IT MS see main text. For peak assignment, please see S2 Table. https://doi.org/10.1371/journal.pone.0264675.s002S3 Fig. ESI spectra of phosphatidylcholine (PC) fractions from boar, bull, stallion, lion and human samples. Lipid extracts were separated on a normal phase high performance thin-layer chromatography (HPTLC) plate with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). Lipids were made visible under UV light and marked with a pencil. PC fractions were directly analyzed by coupling a TLC plate reader to an ESI mass spectrometer. Mass spectra were recorded in the positive ion mode. For further details on ESI-IT MS see main text. For peak assignment, please see S3 Table. https://doi.org/10.1371/journal.pone.0264675.s003S4 Fig. ESI spectra of phosphatidylinositol (PI) fractions from boar, bull, stallion and human lipid samples. Lipid extracts were separated on a normal phase high performance thin-layer chromatography (HPTLC) plate with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). Lipids were made visible under UV light and marked with a pencil. PI fractions were directly analyzed by coupling a TLC plate reader to an ESI mass spectrometer. Mass spectra were recorded in the negative ion mode. For further details on ESI-IT MS see main text. For peak assignment, please see S4 Table. https://doi.org/10.1371/journal.pone.0264675.s004S5 Fig. ESI spectra of phosphatidylethanolamine (PE) fractions from boar, bull and stallion samples. Lipid extracts were separated on a normal phase high performance thin-layer chromatography (HPTLC) plate with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). Lipids were made visible under UV light and marked with a pencil. PE fractions were directly analyzed by coupling a TLC plate reader to an ESI mass spectrometer. Mass spectra were recorded in the negative ion mode. For further details on ESI-IT MS see main text. For peak assignment, please see S5 Table. https://doi.org/10.1371/journal.pone.0264675.s005S6 Fig. ESI spectra of phosphatidylethanolamine (PE) fractions from lion and human samples. Lipid extracts were separated on a normal phase high performance thin-layer chromatography (HPTLC) plate with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). Lipids were made visible under UV light and marked with a pencil. PE fractions were directly analyzed by coupling a TLC plate reader to an ESI mass spectrometer. Mass spectra were recorded in the negative ion mode. For further details on ESI-IT MS see main text. For peak assignment, please see S5 Table. https://doi.org/10.1371/journal.pone.0264675.s006S7 Fig. Hydrolysis of selected seminal fluid samples over time. The plots of hydrolysis measurements from boar and stallion seminal fluid were fitted by a linear curve (f(x) = a + b×x) and the plots from bull, lion and human were fitted by an exponential growth to a maximum (f(x) = a×e-b×x). Due to these different courses of the hydrolysis reaction between the species, the absolute hydrolysis at a given time point (10 min) was used to compare the mean values of the investigated individuals between the species (see Table 2 of the main text). https://doi.org/10.1371/journal.pone.0264675.s007S8 Fig. Effect of artificial LPC on boar sperm. Beltsville Thawing Solution (BTS, MinitĂŒb GmbH)-diluted boar semen (20 × 106 sperm/ml) was mixed with 20 ÎŒM lysophosphatidylcholine (LPC 16:0, Avanti Polar LipidsÂź, No 855675C). After incubation at 38°C for 30 min, the ratios of total motility (blank boxes) and sperm with an intact acrosome (striped boxes) were analyzed. The lipid extract of washed sperm of this experiment was analyzed by MALDI-TOF MS and the ratio of LPC to total GPC was calculated (for details see Material and Methods of the main text). Incubation with 20 ÎŒM LPC led to 2.4 ± 3.6% inserted LPC in sperm cell membranes. Significant differences in total motility and the percentage of sperm with an intact acrosome between the incubation with 20 ÎŒM LPC and controls are marked by asterisks (P = 0.006 and 0.003, respectively, Wilcoxon signed-rank test, n = 11). https://doi.org/10.1371/journal.pone.0264675.s008S9 Fig. Original TLC pictures. Lipid extracts were separated on normal phase high performance thin-layer chromatography (HPTLC) plates with chloroform/ethanol/water/triethylamine (30:35:7:35, by vol.) as the mobile phase. Plates were air-dried and stained with primuline (Direct Yellow 59, Sigma-Aldrich, Taufkirchen, Germany) (50 mg/l dissolved in acetone/water 80:20, by vol.). BP–blood plasma, SF–seminal fluid, st.–lipid standard mixture made of LPC16:0, SM16:0, PC16:0/18:1, PA 16:0/18:1, PI 16:1/18:1, PE 16:0/18:1, PG 16:0/18:1 (bottom up). https://doi.org/10.1371/journal.pone.0264675.s009S1 Table. Assignment of signals detected in ESI spectra from lysophosphatidylcholine (LPC) spots. https://doi.org/10.1371/journal.pone.0264675.s010S2 Table. Assignment of signals detected in ESI spectra from sphingomyelin (SM) spots. n.a.—not assigned. https://doi.org/10.1371/journal.pone.0264675.s011S3 Table. Assignment of signals detected in ESI spectra from phosphatidylcholine (PC) spots. https://doi.org/10.1371/journal.pone.0264675.s012S4 Table. Assignment of signals detected in ESI spectra from phosphatidylinositol (PI) spots. https://doi.org/10.1371/journal.pone.0264675.s013S5 Table. Assignment of signals detected in ESI spectra from phosphatidylethanolamine (PE) spots. https://doi.org/10.1371/journal.pone.0264675.s014The German Research Council.http://www.plosone.orgdm2022Veterinary Tropical Disease

    The Parkes HI Survey of the Magellanic System

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    We present the first fully and uniformly sampled, spatially complete HI survey of the entire Magellanic System with high velocity resolution, performed with the Parkes Telescope. The final data-cubes have an rms noise of sigma ~ 0.05 K and an effective angular resolution of 16 arcmin. The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are associated with huge gaseous features with a total HI mass of M(HI) = 4.87 10^8 M_sun [d/55 kpc]^2, if all HI gas is at the same distance of 55 kpc. Approximately two thirds of this HI gas is located close to the Magellanic Clouds (Magellanic Bridge and Interface Region), and 25% of the HI gas is associated with the Magellanic Stream. The Leading Arm has a four times lower HI mass than the Magellanic Stream, corresponding to 6% of the total HI mass of the gaseous features. We have analyzed the velocity field of the Magellanic Clouds and their neighborhood introducing a LMC-standard-of-rest frame. The HI in the Magellanic Bridge shows low velocities relative to the Magellanic Clouds suggesting an almost parallel motion, while the gas in the Interface Region has significantly higher relative velocities indicating that this gas is leaving the Magellanic Bridge building up a new section of the Magellanic Stream. The clouds in the Magellanic Stream and the Leading Arm show significant differences, both in the column density distribution and in the shapes of the line profiles. The HI gas in the Magellanic Stream is more smoothly distributed than the gas in the Leading Arm. These morphological differences can be explained if the Leading Arm is at considerably lower z-heights and embedded in a higher pressure ambient medium.Comment: 23 pages, 18 figures, accepted for publication in A&

    The MK2 cascade mediates transient alteration in mGluRLTD and spatial learning in a murine model of Alzheimer’s disease

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    A key aim of Alzheimer disease research is to develop efficient therapies to prevent and/or delay the irreversible progression of cognitive impairments. Early deficits in long-term potentiation (LTP) are associated with the accumulation of amyloid beta in rodent models of the disease, however, less is known about how mGluR-mediated long-term depression (mGluR-LTD) is affected. In this study, we have found that mGluR-LTD is enhanced in the APPswe/PS1dE9 mouse at 7 but returns to wild-type levels at 13 months of age. This transient over-activation of mGluR signalling is coupled with impaired LTP and shifts the dynamic range of synapses towards depression. These alterations in synaptic plasticity are associated with an inability to utilise cues in a spatial learning task. The transient dysregulation of plasticity can be prevented by genetic deletion of the MAP kinase-activated protein kinase 2 (MK2), a substrate of p38 MAPK, demonstrating that manipulating the mGluR-p38 MAPK-MK2 cascade at 7 months can prevent the shift in synapse dynamic range. Our work reveals the MK2 cascade as a potential pharmacological target to correct the over-activation of mGluR signalling
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