283 results on '"Liermann, A."'
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2. Synthesis and Structure of Two New Cadmium Carbonates at Extreme Conditions
- Author
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Wang, Yu, Bayarjargal, Lkhamsuren, Bykova, Elena, Spahr, Dominik, Bykov, Maxim, Milman, Victor, Giordano, Nico, Fedotenko, Timofey, Liermann, Hanns-Peter, and Winkler, Bjoern
- Abstract
We synthesized CdC2O5and a new high-pressure polymorph of CdCO3by laser heating otavite, CdCO3, in CO2at 43 GPa. The structure of CdC2O5contains pyramidal [C4O10]4–building blocks formed by [CO4] tetrahedra, where the carbon is in 4-fold coordination. In addition, we found a new monoclinic (P21/c) high-pressure polymorph of CdCO3with trigonal [CO3]2–groups. Both new structures were characterized by single-crystal X-ray diffraction, Raman spectroscopy, and DFT calculations. more...
- Published
- 2024
- Full Text
- View/download PDF
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3. Thermal and combined high-temperature and high-pressure behavior of a natural intermediate scapolite
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Lotti, Paolo, Gatta, G. Diego, Gigli, Lara, Krüger, Hannes, Kahlenberg, Volker, Meven, Martin, Comboni, Davide, Milani, Sula, Merlini, Marco, and Liermann, Hanns-Peter
- Abstract
A natural intermediate member of the scapolite solid solution {Me47; chemical formula: (Na1.86Ca1.86K0.23Fe0.01)(Al4.36Si7.64)O24[Cl0.48(CO3)0.48(SO4)0.01]}, with the unusual I4/mspace group, has been studied at various temperatures and combined high-Tand high-Pby means of in situ single-crystal and powder X-ray diffraction, using both conventional and synchrotron X-ray sources. In addition, single-crystal neutron diffraction data were collected at ambient-Tand 685 °C. A fit of the experimental V-Tdata with a thermal equation of state yielded a thermal expansion coeficient at ambient conditions: αV25°C= 1/V0·(∂V/∂T)P,25°C= 1.74(3)·10–5K–1. A comparative analysis of the elastic behavior of scapolite based on this study and previous high-TXRD data suggests that a thorough re-investigation of the diferent members of the marialite-meionite solid solution is needed to fully understand the role of crystal chemistry on the thermal behavior of these complex nonbinary solid solutions. The experimental data obtained within the full temperature range of analysis at ambient pressure confirm that the investigated sample always preserves the I4/mspace group, and possible implications on the metastability of I4/mintermediate scapolite are discussed. Neutron difraction data show that no significant Si and Al rearrangement among the Tsites occurs between 25 and 685 °C. The combined high-Tand high-Pdata show that at 650 °C and between 10.30(5) and 10.71(5) GPa a phase transition toward a triclinic polymorph occurs, with a positive Clapeyron slope (i.e., dP/dT> 0). A comprehensive description of the atomic-scale structure deformation mechanisms induced by temperature and/or pressure, including those leading to structural instability, is provided based on single-crystal structure refinements. more...
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- 2024
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4. Cryptosporidium parvumcompetes with the intestinal epithelial cells for glucose and impairs systemic glucose supply in neonatal calves.
- Author
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Dengler, Franziska, Hammon, Harald M., Liermann, Wendy, Görs, Solvig, Bachmann, Lisa, Helm, Christiane, Ulrich, Reiner, and Delling, Cora
- Abstract
Cryptosporidiosis is one of the main causes of diarrhea in children and young livestock. The interaction of the parasite with the intestinal host cells has not been characterized thoroughly yet but may be affected by the nutritional demand of the parasite. Hence, we aimed to investigate the impact of C. parvum infection on glucose metabolism in neonatal calves. Therefore, N = 5 neonatal calves were infected with C. parvum on the first day of life, whereas a control group was not (N = 5). The calves were monitored clinically for one week, and glucose absorption, turnover and oxidation were assessed using stable isotope labelled glucose. The transepithelial transport of glucose was measured using the Ussing chamber technique. Glucose transporters were quantified on gene and protein expression level using RT-qPCR and Western blot in the jejunum epithelium and brush border membrane preparations. Plasma glucose concentration and oral glucose absorption were decreased despite an increased electrogenic phlorizin sensitive transepithelial transport of glucose in infected calves. No difference in the gene or protein abundance of glucose transporters, but an enrichment of glucose transporter 2 in the brush border was observed in the infected calves. Furthermore, the mRNA for enzymes of the glycolysis pathway was increased indicating enhanced glucose oxidation in the infected gut. In summary, C. parvum infection modulates intestinal epithelial glucose absorption and metabolism. We assume that the metabolic competition of the parasite for glucose causes the host cells to upregulate their uptake mechanisms and metabolic machinery to compensate for the energy losses. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
- Full Text
- View/download PDF
5. NFDI4Chem—A Research Data Network for International Chemistry
- Author
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Steinbeck, Christoph, Koepler, Oliver, Herres-Pawlis, Sonja, Bach, Felix, Jung, Nicole, Razum, Matthias, Liermann, Johannes C., and Neumann, Steffen
- Abstract
Research data provide evidence for the validation of scientific hypotheses in most areas of science. Open access to them is the basis for true peer review of scientific results and publications. Hence, research data are at the heart of the scientific method as a whole. The value of openly sharing research data has by now been recognized by scientists, funders and politicians. Today, new research results are increasingly obtained by drawing on existing data. Many organisations such as the Research Data Alliance (RDA), the goFAIR initiative, and not least IUPAC are supporting and promoting the collection and curation of research data. One of the remaining challenges is to find matching data sets, to understand them and to reuse them for your own purpose. As a consequence, we urgently need better research data management. more...
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- 2023
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6. A hydrogen-enriched layer in the topmost outer core sourced from deeply subducted water
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Kim, Taehyun, O’Rourke, Joseph G., Lee, Jeongmin, Chariton, Stella, Prakapenka, Vitali, Husband, Rachel J., Giordano, Nico, Liermann, Hanns-Peter, Shim, Sang-Heon, and Lee, Yongjae
- Abstract
The Earth’s core–mantle boundary presents a dramatic change in materials, from silicate to metal. While little is known about chemical interactions between them, a thin layer with a lower velocity has been proposed at the topmost outer core (Eʹ layer) that is difficult to explain with a change in concentration of a single light element. Here we perform high-temperature and -pressure laser-heated diamond-anvil cell experiments and report the formation of SiO2and FeHxfrom a reaction between water from hydrous minerals and Fe–Si alloys at the pressure–temperature conditions relevant to the Earth’s core–mantle boundary. We suggest that, if water has been delivered to the core–mantle boundary by subduction, this reaction could enable exchange of hydrogen and silicon between the mantle and the core. The resulting H-rich, Si-deficient layer formed at the topmost core would have a lower density, stabilizing chemical stratification at the top of the core, and a lower velocity. We suggest that such chemical exchange between the core and mantle over gigayears of deep transport of water may have contributed to the formation of the putative Eʹ layer. more...
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- 2023
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7. NFDI4Chem—A Research Data Network for International Chemistry.
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Steinbeck, Christoph, Koepler, Oliver, Herres-Pawlis, Sonja, Bach, Felix, Jung, Nicole, Razum, Matthias, Liermann, Johannes C., and Neumann, Steffen
- Abstract
Copyright of Chemistry International is the property of International Union of Pure & Applied Chemistry (IUPAC) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2023
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8. Synthesis and Structure of Pb[C2O5]: An Inorganic Pyrocarbonate Salt.
- Author
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Spahr, Dominik, König, Jannes, Bayarjargal, Lkhamsuren, Luchitskaia, Rita, Milman, Victor, Perlov, Alexander, Liermann, Hanns-Peter, and Winkler, Björn
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- 2022
- Full Text
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9. Historical Records Reveal Changes to the Migration Timing and Abundance of Winter Steelhead in Olympic Peninsula Rivers, Washington State, USA.
- Author
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McMillan, John R., Sloat, Matthew R., Liermann, Martin, and Pess, George
- Subjects
RAINBOW trout ,WINTER ,PENINSULAS ,HISTORICAL source material ,LABOR mobility ,DEMOGRAPHIC change - Abstract
We analyzed multiple historical data sources (circa 1948–1960) to estimate migration timing and abundance of Olympic Peninsula winter steelhead Oncorhynchus mykiss in the Quillayute, Hoh, Queets, and Quinault rivers, Washington, to provide context for contemporary (circa 1980–2017) population trends. Contemporary wild winter steelhead migrations peak 1–2 months later than historical migrations, and migration timing breadth has contracted by up to 26 d (a 37% reduction of the interquartile range of the migration timing distribution). Migration timing changes coincide with an era of peak industrial forestry and introductions of early migrating hatchery winter steelhead stocks. We estimate that contemporary mean wild winter steelhead abundance has declined by 55% across populations compared to circa 1948–1960 historical means, with 1920s records suggesting declines of up to 77% in the Queets River. Migration timing shifts and the magnitude of population declines are not evident in modern fisheries monitoring records, which began around 1980. Our results demonstrate how modest extensions of the period of record (e.g., 30 years) increase the power to identify population changes that are not readily apparent from contemporary fisheries monitoring programs. Historical fisheries data can help managers to avoid the shifting baseline syndrome and provide important reference points for rebuilding population diversity and abundance. [ABSTRACT FROM AUTHOR] more...
- Published
- 2022
- Full Text
- View/download PDF
10. Novel Calcium sp³ Carbonate CaC2O5-I42d May Be a Carbon Host in Earth's Lower Mantle.
- Author
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König, Jannes, Spahr, Dominik, Bayarjargal, Lkhamsuren, Gavryushkin, Pavel N., Sagatova, Dinara, Sagatov, Nursultan, Milman, Victor, Liermann, Hanns-Peter, and Winkler, Björn
- Published
- 2022
- Full Text
- View/download PDF
11. Structural Diversity of Magnetite and Products of Its Decomposition at Extreme Conditions.
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Khandarkhaeva, Saiana, Fedotenko, Timofey, Chariton, Stella, Bykova, Elena, Ovsyannikov, Sergey V., Glazyrin, Konstantin, Liermann, Hanns-Peter, Prakapenka, Vitali, Dubrovinskaia, Natalia, and Dubrovinsky, Leonid more...
- Published
- 2022
- Full Text
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12. Hiltl, Oliver, Rechtsbegründung in multikultureller Gesellschaft
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Traniello, Christiane Liermann
- Published
- 2024
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13. Sr3[CO4]O Antiperovskite with Tetrahedrally Coordinated sp³-Hybridized Carbon and OSr6 Octahedra.
- Author
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Spahr, Dominik, König, Jannes, Bayarjargal, Lkhamsuren, Gavryushkin, Pavel N., Milman, Victor, Liermann, Hanns-Peter, and Winkler, Björn
- Published
- 2021
- Full Text
- View/download PDF
14. Ecological Assessment and Evaluation of Potential Eradication Approaches for Introduced Redside Shiners in a Montane Lake.
- Author
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Smith, Troy W., Liermann, Brad W., and Eby, Lisa A.
- Subjects
ECOLOGICAL assessment ,FORAGE fishes ,INTRODUCED fishes ,RAINBOW trout ,INTRODUCED species - Abstract
Introduced species can alter the dynamics of food webs, species interactions, populations, and communities and can reduce a system's recreational value. Several reports have documented the establishment of Redside Shiners Richardsonius balteatus in mountain lakes, resulting in declines in sizes and abundance of salmonid species. An illegal bait bucket release introduced Redside Shiners into Green Canyon Lake, Montana, USA, in the 1980s. Recently, local anglers began complaining of decreases in size and catch rates of Westslope Cutthroat Trout (WCT) Oncorhynchus clarkii lewisi. Our first objective was to understand the diet overlap between Redside Shiners and WCT in Green Canyon Lake. Based on δ15N and δ13C isotopic signatures and diet contents, we found little evidence that WCT were substantially preying upon Redside Shiners. We found moderate diet overlap between WCT and Redside Shiners, with both species predominately feeding on Diptera. For our second objective, we developed a population model to assess potential options for eradicating Redside Shiners. We observed Redside Shiners up to 7 years of age and with a maximum TL of 159 mm, high annual survival (50%), and mature females at age 2. We used an age‐structured model to evaluate two hypothetical suppression actions: piscicide application and stocking of Rainbow Trout O. mykiss. Four consecutive piscicide treatments had a 20% probability of eradicating Redside Shiners, increasing to a 100% eradication probability after seven treatments. Bioenergetic simulations indicated that an individual Rainbow Trout (500 g) would consume 1,759 g of Redside Shiners annually. Incorporating this predation mortality and a compensatory response (50% increase in age‐1 survival), we estimated that maintained abundances of up to 700 Rainbow Trout would not cause a decline in the Redside Shiner population. Our results suggest that eradication of an introduced prey fish like the Redside Shiner would be difficult and that effective removal will require dedicated effort and resources by managers. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
- Full Text
- View/download PDF
15. Effectiveness monitoring of juvenile Chinook salmon restoration projects in south Lake Washington, Washington State
- Author
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Tabor, Roger A., Liermann, Martin C., Gearns, Howard A., Moore, Zachary J., Lynch, Katherine D., Kurko, Keith, Crittenden, Julie, and Shoemaker, Monica E.
- Abstract
AbstractTabor RA, Liermann MC, Gearns HA, Moore ZJ, Lynch KD, Kurko K, Crittenden J, Shoemaker ME. 2022. Effectiveness monitoring of juvenile Chinook salmon restoration projects in south Lake Washington, Washington State. Lake Reserv Manage. 38:180–196.We evaluated 4 large restoration projects in south Lake Washington that were designed to improve nearshore habitat for lake-rearing juvenile Chinook salmon (Oncorhynchus tshawytscha). Restoration projects included shoreline modification, substrate enhancement, addition of engineered log jams (ELJs), and nonnatal tributary improvements. For most projects, we used a BACI (before-after-control-impact) study design. Projects were evaluated by determining the nighttime abundance of juvenile Chinook salmon through visual observations (primarily snorkeling with some surface observations in small nonnatal tributaries). Juvenile Chinook salmon are typically concentrated in the south end of the lake near their natal stream, and the project that was the farthest away from the natal stream did not appear to be beneficial, likely because few Chinook salmon were present. The highest observed abundance of juvenile Chinook salmon was associated with ELJs, where the abundance in February to April was typically 2 to 5 times higher than along adjacent, open shorelines. From January to April, juvenile Chinook salmon were usually more abundant in a daylighted nonnatal tributary (i.e., reconfigured from an unusable underground culvert to a more natural stream channel at the surface) than in 2 reference sites. Overall, all 4 project types improved juvenile use of the restored area, with substrate enhancement generally having the weakest response and ELJs the strongest response. Although most restoration projects for salmonids in the Pacific Northwest have focused on lotic systems, our results suggest projects in lentic systems may also be beneficial and should be considered by land-use managers.Supplemental data for this article is available online at https://doi.org/10.1080/10402381.2022.2027054 . more...
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- 2022
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16. Synthesis, structure, and single-crystal elasticity of Al-bearing superhydrous phase B
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Li, Xinyang, Speziale, Sergio, Glazyrin, Konstantin, Wilke, Franziska D.H., Liermann, Hanns-Peter, and Koch-Müller, Monika
- Abstract
Dense hydrous magnesium silicates (DHMSs) with large water contents and wide stability fields are a potential H2O reservoir in the deep Earth. Al-bearing superhydrous phase B (shy-B) with a wider stability field than the Al-free counterpart can play an important role in understanding H2O transport in the Earth’s transition zone and topmost lower mantle. In this study, a nominally Al-free and two different Al-bearing shy-B samples with 0.47(2) and 1.35(4) Al atoms per formula unit (pfu), were synthesized using a rotating multi-anvil press. Their single-crystal structures were investigated by X‑ray diffraction (XRD) complemented by Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR). Single-crystal XRD shows that the cell parameters decrease with increasing Al-content. By combining X‑ray diffraction and spectroscopy results, we conclude that the Al-poor shy-B crystallizes in the Pnn2 space group with hydrogen in two different general positions. Based on the results of the single-crystal X‑ray diffraction refinements combined with FTIR spectroscopy, three substitutions mechanisms are proposed: 2Al3+= Mg2++ Si4+; Mg2+= □Mg2++ 2H+(□Mg2+means vacancy in Mg site); Si4+= Al3++ H+. Thus, in addition to the two general H positions, hydrogen is incorporated into the hydrous mineral via point defects. The elastic stiffness coefficients were measured for the Al-shy-B with 1.35 pfu Al by Brillouin scattering (BS). Al-bearing shy-B shows lower C11, higher C22, and similar C33when compared to Al-free shy-B. The elastic anisotropy of Al-bearing shy-B is also higher than that of the Al-free composition. Such different elastic properties are due to the effect of lattice contraction as a whole and the specific chemical substitution mechanism that affect bonds strength. Al-bearing shy-B with lower velocity, higher anisotropy, and wider thermodynamic stability can help understand the low-velocity zone and the high-anisotropy region in the subducted slab located in Tonga. more...
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- 2022
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17. Wasser in der Erde und in kosmischen Eiswelten
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Loerting, Thomas and Liermann, Hanns‐Peter
- Abstract
Der Einfluss von Wasser auf die Dynamik von Planeten wie der Erde oder Neptun sind nach wie vor nur sehr rudimentär verstanden. So wird Wasser durch wasserhaltige Minerale mittels Subduktionszonen ins Erdinnere transportiert, ohne dass klar ist, ob es dort gespeichert wird oder aber durch Vulkanismus wieder an die Oberfläche gelangt. Experimente mit Hochdruckpressen erlauben es, extreme Bedingungen im Erdinneren nachzustellen und die dortigen Prozesse durch Untersuchung der physikalischen Eigenschaften mittels neuester Röntgentechnik zu entschlüsseln. Auch die innere Struktur vieler Himmelskörper ist nach wie vor ungeklärt. Die Frage, ob es unterirdische Ozeane auf Eismonden gibt oder feste Schichten von verschiedenen Eispolymorphen, ist genauso ungeklärt wie die Frage, ob das Magnetfeld der Eisriesen durch Eis bei Ultrahochdruck entsteht. Noch viel weniger wissen wir über die Prozesse im Eismantel der interstellaren Staubkörner. Auch wenn es nur kleine, ferne Körner sein mögen, liegen viele Antworten auf die Rätsel des Lebens und der Evolution in der Chemie dieser amorphen Eisschichten verborgen. Welche Rolle Wasser in der Dynamik des Inneren von Erde und Planeten sowie in vielen astrophysikalischen Prozessen spielt, ist noch weitgehend unklar. Dies liegt hauptsächlich an der Unzugänglichkeit solcher Orte. Daher kommt Laborexperimenten, die extreme Bedingungen im Inneren von Planeten und im Weltall zugänglich machen, eine hohe Bedeutung zu. In Kombination mit modernen Methoden zur Aufklärung der Struktur und Dynamik erlauben diese Methoden, Befunde aus der Ferne zu treffen. Bild: NASA/JPL‐Caltech more...
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- 2022
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18. Weak cubic CaSiO3perovskite in the Earth’s mantle
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Immoor, J., Miyagi, L., Liermann, H.-P., Speziale, S., Schulze, K., Buchen, J., Kurnosov, A., and Marquardt, H.
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Cubic CaSiO3perovskite is a major phase in subducted oceanic crust, where it forms at a depth of about 550 kilometres from majoritic garnet1,2,28. However, its rheological properties at temperatures and pressures typical of the lower mantle are poorly known. Here we measured the plastic strength of cubic CaSiO3perovskite at pressure and temperature conditions typical for a subducting slab up to a depth of about 1,200 kilometres. In contrast to tetragonal CaSiO3, previously investigated at room temperature3,4, we find that cubic CaSiO3perovskite is a comparably weak phase at the temperatures of the lower mantle. We find that its strength and viscosity are substantially lower than that of bridgmanite and ferropericlase, possibly making cubic CaSiO3perovskite the weakest lower-mantle phase. Our findings suggest that cubic CaSiO3perovskite governs the dynamics of subducting slabs. Weak CaSiO3perovskite further provides a mechanism to separate subducted oceanic crust from the underlying mantle. Depending on the depth of the separation, basaltic crust could accumulate at the boundary between the upper and lower mantle, where cubic CaSiO3perovskite may contribute to the seismically observed regions of low shear-wave velocities in the uppermost lower mantle5,6, or sink to the core–mantle boundary and explain the seismic anomalies associated with large low-shear-velocity provinces beneath Africa and the Pacific7–9. more...
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- 2022
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19. Sr[C2O5] is an Inorganic Pyrocarbonate Salt with [C2O5]2–Complex Anions
- Author
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Spahr, Dominik, König, Jannes, Bayarjargal, Lkhamsuren, Milman, Victor, Perlov, Alexander, Liermann, Hanns-Peter, and Winkler, Björn
- Abstract
The synthesis of a novel type of carbonate, namely of the inorganic pyrocarbonate salt Sr[C2O5], which contains isolated [C2O5]2–-groups, significantly extends the crystal chemistry of inorganic carbonates beyond the established sp2- and sp3-carbonates. We synthesized Sr[C2O5] in a laser-heated diamond anvil cell by reacting Sr[CO3] with CO2. By single crystal synchrotron diffraction, Raman spectroscopy, and density functional theory (DFT) calculations, we show that it is a pyrocarbonate salt. Sr[C2O5] is the first member of a novel family of inorganic carbonates. We predict, based on DFT calculations, that further inorganic pyrocarbonates can be obtained and that these will be relevant to geoscience and may provide a better understanding of reactions converting CO2into useful inorganic compounds. more...
- Published
- 2022
- Full Text
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20. Historical Records Reveal Changes to the Migration Timing and Abundance of Winter Steelhead in Olympic Peninsula Rivers, Washington State, USA
- Author
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McMillan, John R., Sloat, Matthew R., Liermann, Martin, and Pess, George
- Abstract
We analyzed multiple historical data sources (circa 1948–1960) to estimate migration timing and abundance of Olympic Peninsula winter steelhead Oncorhynchus mykissin the Quillayute, Hoh, Queets, and Quinault rivers, Washington, to provide context for contemporary (circa 1980–2017) population trends. Contemporary wild winter steelhead migrations peak 1–2 months later than historical migrations, and migration timing breadth has contracted by up to 26 d (a 37% reduction of the interquartile range of the migration timing distribution). Migration timing changes coincide with an era of peak industrial forestry and introductions of early migrating hatchery winter steelhead stocks. We estimate that contemporary mean wild winter steelhead abundance has declined by 55% across populations compared to circa 1948–1960 historical means, with 1920s records suggesting declines of up to 77% in the Queets River. Migration timing shifts and the magnitude of population declines are not evident in modern fisheries monitoring records, which began around 1980. Our results demonstrate how modest extensions of the period of record (e.g., 30 years) increase the power to identify population changes that are not readily apparent from contemporary fisheries monitoring programs. Historical fisheries data can help managers to avoid the shifting baseline syndrome and provide important reference points for rebuilding population diversity and abundance. more...
- Published
- 2022
- Full Text
- View/download PDF
21. Structural Diversity of Magnetite and Products of Its Decomposition at Extreme Conditions
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Khandarkhaeva, Saiana, Fedotenko, Timofey, Chariton, Stella, Bykova, Elena, Ovsyannikov, Sergey V., Glazyrin, Konstantin, Liermann, Hanns-Peter, Prakapenka, Vitali, Dubrovinskaia, Natalia, and Dubrovinsky, Leonid more...
- Abstract
Magnetite, Fe3O4, is the oldest known magnetic mineral and archetypal mixed-valence oxide. Despite its recognized role in deep Earth processes, the behavior of magnetite at extreme high-pressure high-temperature (HPHT) conditions remains insufficiently studied. Here, we report on single-crystal synchrotron X-ray diffraction experiments up to ∼80 GPa and 5000 K in diamond anvil cells, which reveal two previously unknown Fe3O4polymorphs, γ-Fe3O4with the orthorhombic Yb3S4-type structure and δ-Fe3O4with the modified Th3P4-type structure. The latter has never been predicted for iron compounds. The decomposition of Fe3O4at HPHT conditions was found to result in the formation of exotic phases, Fe5O7and Fe25O32, with complex structures. Crystal-chemical analysis of iron oxides suggests the high-spin to low-spin crossover in octahedrally coordinated Fe3+in the pressure interval between 43 and 51 GPa. Our experiments demonstrate that HPHT conditions promote the formation of ferric-rich Fe–O compounds, thus arguing for the possible involvement of magnetite in the deep oxygen cycle. more...
- Published
- 2022
- Full Text
- View/download PDF
22. Sr3[CO4]O Antiperovskite with Tetrahedrally Coordinated sp3-Hybridized Carbon and OSr6Octahedra
- Author
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Spahr, Dominik, König, Jannes, Bayarjargal, Lkhamsuren, Gavryushkin, Pavel N., Milman, Victor, Liermann, Hanns-Peter, and Winkler, Björn
- Abstract
We have synthesized the orthocarbonate Sr3[CO4]O in a laser-heated diamond anvil cell at 20 and 30 GPa by heating to ≈3000 (300) K. Afterward, we recovered the orthocarbonate with [CO4]4–groups at ambient conditions. Single-crystal diffraction shows the presence of [CO4]4–groups, i.e., sp3-hybridized carbon tetrahedrally coordinated by covalently bound oxygen atoms. The [CO4]4–tetrahedra are located in a cage formed by corner-sharing OSr6octahedra, i.e., octahedra with oxygen as a central ion, forming an antiperovskite-type structure. At high pressures, the octahedra are nearly ideal and slightly rotated. The high-pressure phase is tetragonal (I4/mcm). Upon pressure release, there is a phase transition with a symmetry lowering to an orthorhombic phase (Pnma), where the octahedra tilt and deform slightly. more...
- Published
- 2021
- Full Text
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23. Ecological Assessment and Evaluation of Potential Eradication Approaches for Introduced Redside Shiners in a Montane Lake
- Author
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Smith, Troy W., Liermann, Brad W., and Eby, Lisa A.
- Abstract
Introduced species can alter the dynamics of food webs, species interactions, populations, and communities and can reduce a system’s recreational value. Several reports have documented the establishment of Redside Shiners Richardsonius balteatusin mountain lakes, resulting in declines in sizes and abundance of salmonid species. An illegal bait bucket release introduced Redside Shiners into Green Canyon Lake, Montana, USA, in the 1980s. Recently, local anglers began complaining of decreases in size and catch rates of Westslope Cutthroat Trout (WCT) Oncorhynchus clarkii lewisi. Our first objective was to understand the diet overlap between Redside Shiners and WCT in Green Canyon Lake. Based on δ15N and δ13C isotopic signatures and diet contents, we found little evidence that WCT were substantially preying upon Redside Shiners. We found moderate diet overlap between WCT and Redside Shiners, with both species predominately feeding on Diptera. For our second objective, we developed a population model to assess potential options for eradicating Redside Shiners. We observed Redside Shiners up to 7 years of age and with a maximum TL of 159 mm, high annual survival (50%), and mature females at age 2. We used an age‐structured model to evaluate two hypothetical suppression actions: piscicide application and stocking of Rainbow Trout O. mykiss. Four consecutive piscicide treatments had a 20% probability of eradicating Redside Shiners, increasing to a 100% eradication probability after seven treatments. Bioenergetic simulations indicated that an individual Rainbow Trout (500 g) would consume 1,759 g of Redside Shiners annually. Incorporating this predation mortality and a compensatory response (50% increase in age‐1 survival), we estimated that maintained abundances of up to 700 Rainbow Trout would not cause a decline in the Redside Shiner population. Our results suggest that eradication of an introduced prey fish like the Redside Shiner would be difficult and that effective removal will require dedicated effort and resources by managers. more...
- Published
- 2021
- Full Text
- View/download PDF
24. The Thermal Conductivity of Bridgmanite at Lower Mantle Conditions Using a Multi‐Technique Approach
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Edmund, Eric, Chuvashova, Irina, Konôpková, Zuzana, Husband, Rachel, Strohm, Cornelius, Appel, Karen, Bähtz, Carsten, Ball, Orianna, Bouffetier, Victorien, Brugman, Kara, Buakor, Khachiwan, Chantel, Julien, Chariton, Stella, Duff, Matthew, Dwivedi, Anand, Glazyrin, Konstantin, Hosseini‐Saber, S. M. A., Jaisle, Nicolas, Laurus, Torsten, Li, Xiang, Masani, Bernhard, McHardy, James, McMahon, Malcolm, Merkel, Sébastien, Mohrbach, Katharina, Mondal, Anshuman, Morard, Guillaume, Prakapenka, Vitali B., Prescher, Clemens, Ryu, Young‐Jay, Schwinkendorf, Jan‐Patrick, Tang, Minxue, Younes, Zena, Sanchez‐Valle, Carmen, Liermann, Hanns‐Peter, Badro, James, Lin, Jung‐Fu, McWilliams, R. Stewart, and Goncharov, Alexander F. more...
- Abstract
The thermal conductivity of bridgmanite, the primary constituent of the Earth's lower mantle, has been investigated using diamond anvil cells at pressures up to 85 GPa and temperatures up to 3,100 K. We report the results of time‐domain optical laser flash heating and X‐ray Free Electron Laser heating experiments from a variety of bridgmanite samples with different Al and Fe contents. The results demonstrate that Fe or Fe,Al incorporation in bridgmanite reduces thermal conductivity by about 50% in comparison to end‐member MgSiO3at the pressure‐temperature conditions of Earth's lower mantle. The effect of temperature on the thermal conductivity at 28–60 GPa is moderate, well described as k=k300(300/T)a${k={k}_{300}(300/T)}^{a}$, where ais 0.2–0.5. The results yield thermal conductivity of 7.5–15 W/(m × K) in the thermal boundary layer of the lowermost mantle composed of Fe,Al‐bearing bridgmanite. Heat transport from the Earth's core and mantle to the surface drives plate tectonics and is crucial for sustaining the magnetic field which shields the surface from the solar wind. To quantify the heat transport process across the core‐mantle boundary layer, it is important to know thermal conductivity of major constituent minerals of the lower mantle in the region. Bridgmanite, which was called silicate perovskite, is the most abundant mineral in the lower mantle. Here we measured thermal conductivity on lab‐grown bridgmanite with different Fe and Al compositions compressed at the tips of two opposing diamonds to reproduce relevant pressures in the mantle. To obtain thermal conductivity, we applied optical and X‐ray Free Electron Lasers combined with optical spectroscopy and X‐ray diffraction to heat and measure time‐dependent temperature distributions of the sample. Our study provides relevant high pressure‐temperature data sets to better constrain the heat flux across the core‐mantle boundary. We measured thermal conductivity of Fe,Al‐bearing bridgmanite, the most abundant mineral in the Earth's lower mantle, up to 85 GPa and 3,100 KFinite‐element calculations to temperatures obtained from laser flash and X‐ray Free Electron Laser heating measurements are fitted to evaluate temperature effect on conductivityWe assessed pressure, temperature, composition effects on thermal conductivity of bridgmanite at the thermal boundary layer of the lowermost mantle We measured thermal conductivity of Fe,Al‐bearing bridgmanite, the most abundant mineral in the Earth's lower mantle, up to 85 GPa and 3,100 K Finite‐element calculations to temperatures obtained from laser flash and X‐ray Free Electron Laser heating measurements are fitted to evaluate temperature effect on conductivity We assessed pressure, temperature, composition effects on thermal conductivity of bridgmanite at the thermal boundary layer of the lowermost mantle more...
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- 2024
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25. Radiographic Response of Vessel Involvement and Resectability After Neoadjuvant Chemoradiation in Patients With Locally Advanced Pancreatic Cancer
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Naumann, Patrick, Ottensmeier, Friederike, Farnia, Benjamin, Ben-Josef, Edgar, Liermann, Jakob, Maier-Hein, Klaus H., Hackert, Thilo, and Debus, Jürgen
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- 2020
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26. Reduced order indirect self-tuning regulator for a novel pneumatic tele-operation system
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Baayoun, Mohamad, Daher, Naseem, and Liermann, Matthias
- Abstract
This article presents a reduced order indirect self-tuning regulator for a passive pneumatic tele-operation system, which is intended for use in medical surgeries in magnetic resonance imaging environments with short transmission distances (≈10m), where force feedback is required. The novel tele-operation system uses less active components as compared to conventional systems and realizes a bilateral control without the use of a force or pressure sensor. The proposed adaptive control system is validated in simulation and experimentation on a test rig built for this purpose. Special attention is given to the notion of transparency of the system, which is the ratio between the resistance of the master device experienced by the operator and the actual resistance of the remote environment in contact with the slave device. The adaptive controller shows advantage over a previously designed non-adaptive control system design in terms of stiffness, damping, and transparency. more...
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- 2020
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27. Economic crises, child mortality and the protective role of public health expenditure.
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Tejada, Cesar Augusto Oviedo, Triaca, Lívia Madeira, Liermann, Nathiéle Hellwig, Ewerling, Fernanda, and Costa, Janaína Calu
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FINANCIAL crises ,PUBLIC spending ,ECONOMIC indicators ,FIXED effects model ,INFANT mortality ,CHILD mortality - Abstract
The aim of the study was to analyze how economic crises affect child health globally and between subgroups of countries with different levels of income. Data from the World Bank and the World Health Organization were used for 127 countries between 1995 and 2014. A fixed effects model was used, evaluating the effect of the change on macroeconomic indicators (GDP per capita, unemployment and inflation rates and misery index) in neonatal, infant and under-five mortality rates. Moreover, we evaluated whether there was a change in the association effect according to the income of the countries and also analyzed the role of public health expenditure in this association. Evidence has shown that worse economic indicators (lower GDP per capita, higher inflation, unemployment rates and misery index) are associated with higher child mortality rates. In the subsamples by income strata, the same association is observed, but with effects of greater magnitude for low- and middle-income countries. We also verified that a higher percentage in public health expenditures alleviates the effects of economic indicators on child mortality rates. Thus, more attention needs to be paid to the harmful effects of the macroeconomic crises to ensure improvements in child health. [ABSTRACT FROM AUTHOR] more...
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- 2019
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28. Parametric mapping of dynamic Ga-68 FAPI-46 PET data of 43 patients with pancreatic diseases: feasibility and diagnostic value
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von Goetze, I., Buchholz, H. G., Liermann, J., Gutjahr, E., Heger, U., Schreckenberger, M., Haberkorn, U., and Röhrich, M.
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- 2024
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29. Survival During Long-Term Starvation: Global Proteomics Analysis of Geobacter sulfurreducensunder Prolonged Electron-Acceptor Limitation
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Bansal, Reema, Helmus, Ruth A., Stanley, Bruce A., Zhu, Junjia, Liermann, Laura J., Brantley, Susan L., and Tien, Ming
- Abstract
The bioavailability of terminal electron acceptors (TEAs) and other substrates affects the efficiency of subsurface bioremediation. While it is often argued that microorganisms exist under “feast or famine”, in the laboratory most organisms are studied under “feast” conditions, whereas they typically encounter “famine” in nature. The work described here aims to understand the survival strategies of the anaerobe Geobacter sulfurreducesunder TEA-starvation conditions. Cultures were starved for TEA and at various times sampled to perform global comparative proteomic analysis using iTRAQ to obtain insight into the dynamics of change in proteins/enzymes expression associated with change in nutrient availability/environmental stress. Proteins varying in abundance with a high level of statistical significance (p< 0.05) were identified to understand how cells change from midlog to (i) stationary phase and (ii) conditions of prolonged starvation (survival phase). The most highly represented and significantly up-regulated proteins in the survival phase cells are involved in energy metabolism, cell envelope, and transport and binding functional categories. The majority of the proteins were predicted to be localized in the cell membranes. These results document that changes in the outer and cytoplasmic membranes are needed for survival of Geobacterunder starvation conditions. The cell shuts down anabolic processes and becomes poised, through changes in its membrane proteins, to sense nutrients in the environment, to transport nutrients into the cell, and to detect or utilize TEAs that are encountered. Under TEA-limiting conditions, the cells turned from translucent white to red in color, indicating higher heme content. The increase in heme content supported proteomics results showing an increase in the number of cytochromes involved in membrane electron transport during the survival phase. The cell is also highly reduced with minimal change in energy charge (ATP to total adenine nucleotide ratio). Nonetheless, these proteomic and biochemical results indicate that even under TEA starvation cells remain poised for bioremediation. more...
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- 2024
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30. A New Mechanism for Stishovite Formation During Rapid Compression of Quartz and Implications for Asteroid Impacts
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Otzen, Christoph, Liermann, Hanns‐Peter, and Langenhorst, Falko
- Abstract
Shock‐induced transformations of quartz to high‐pressure polymorphs and diaplectic glass are decisive in identifying impact cratering events. Under shock compression, quartz can melt in local hot spots and crystallization of these silica melts under pressure can yield the high‐pressure mineral stishovite. A solid‐state transition to stishovite in relation to the formation of amorphous lamellae was already suggested in the late 1960s, but this idea was never comprehensively proven. Therefore, the mechanism responsible for such an intracrystalline stishovite formation is unknown to date. Herein, crystallographically oriented single crystals of quartz were compressed and decompressed in a membrane‐driven diamond anvil cell. These experiments aim at simulating the pressure paths of natural impacts on the timescale of seconds using compression rates between 0.2 and 0.6 GPa/s and peak pressures between 20 and 37 GPa. During the compression of quartz, the time‐resolved synchrotron X‐ray diffraction patterns reveal the almost simultaneous formation of two high‐pressure polymorphs, the recently identified rosiaite‐structured silica and stishovite. Transmission electron microscopic observations of recovered samples show that stishovite occurs as arrays of uniformly oriented nanometer‐sized crystals in amorphous intracrystalline lamellae. These observations indicate that the numerous stishovite crystals likely nucleated from the structurally similar rosiaite phase and thus inherited their uniform orientation during compression. During decompression, the metastable and non‐quenchable rosiaite‐structured phase collapsed to the amorphous stishovite‐containing lamellae. These findings attest to a novel mechanism of the formation of stishovite in the solid state and provide an explanation for similar microstructural occurrences of stishovite in impact‐metamorphic rocks and shocked meteorites. The extreme pressures and temperatures of asteroid impacts on planetary surfaces result in irreversible changes in the affected rocks. The mineral quartz can then display characteristic amorphous lamellae and crystals of the high‐pressure mineral stishovite. While stishovite usually crystallizes from locally molten silica under pressure, its formation in the solid state free of silica melts has remained enigmatic to date. Here, we simulated asteroid impacts on the time scale of seconds and at ambient temperature through experiments of rapid compression and decompression of quartz. The crystallographic changes during the experiments and the microstructural observations of the recovered samples provide evidence that stishovite is indeed formed in the solid state during compression of quartz. In particular, a large number of stishovite crystals form in an identical crystallographic orientation through nucleation from the structurally similar rosiaite‐structured silica phase. The latter is formed metastably during compression. The final microstructure consists of the numerous stishovite crystals located in amorphous lamellae, because the metastable rosiaite‐structured phase transforms into amorphous silica during decompression. The discoveries describe a novel mechanism for rapid stishovite formation in the solid state, explaining very similar stishovite occurrences in meteorites and rock samples recovered from impact sites. Stishovite can form in the solid state from compressed quartz through nucleation from a transient rosiaite‐structured silica phaseThe solid state transition from quartz to finally stishovite results in a uniform orientation relationshipShock‐metamorphic features in quartz can be mimicked by compression in the diamond anvil cell Stishovite can form in the solid state from compressed quartz through nucleation from a transient rosiaite‐structured silica phase The solid state transition from quartz to finally stishovite results in a uniform orientation relationship Shock‐metamorphic features in quartz can be mimicked by compression in the diamond anvil cell more...
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- 2024
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31. Direct antiviral therapy for treatment of hepatitis C: A real-world study from Brazil
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Lobato, Cirley Maria de Oliveira, Codes, Liana, Silva, Giovanni Faria, Souza, Aécio Flávio Meirelles, Coelho, Henrique Sérgio Moraes, Pedroso, Maria Lucia Alves, Parise, Edison Roberto, Lima, Leila Maria Soares Tojal de Barros, Borba, Luiz Augusto, Evangelista, Andreia Silva, Rezende, Rosamar Eulira Fontes, Cheinquer, Hugo, Kuniyoshi, Aline Satie Oba, Aires, Rodrigo Sebba, Quintela, Eloiza Helena Dias, Mendes, Liliana Sampaio Costa, Nascimento, Fábio Carneiro Vosqui, Medeiros Filho, José Eymard Moraes de, Ferraz, Maria Lúcia Cardoso Gomes, Abdala, Edson, Bittencourt, Paulo Lisboa, de Souza Paiva Ferreira, Adalgisa, Salcedo, Juan Miguel Villalobos, de Lucca Schiavon, Leonardo, de Almeida Lopes, Edmundo Pessoa, Pessôa, Mário Guimarães, Gonçalves, Luciana Lofêgo, Souto, Francisco José Dutra, Hyppolito, Elodie Bomfim, Pereira, Gustavo Henrique Santos, Mattos, Angelo A., de Cássia Martins Alves Silva, Rita, de Lourdes Candolo Martinelli, Ana, Ivantes, Claudia Alexandra Pontes, Mello, Carlos Eduardo Brandão, Gomide, Geisa Perez Medina, Sette Junior, Hoel, de Tarso Aparecida Pinto, Paulo, Romeiro, Fernando Gomes, de Castro Lima, José Milton, Altikes, Isaac, Lyra, André Castro, Garcia, Raquel Francine Liermann, Villela-Nogueira, Cristiane Alves, Cuminale, Renata Cruvinel Cabral, de Omena, Andrea Magalhães Agra, Schiavon, Janaina Luz Narciso, Batista, Andrea Doria, de Liz Pellegrim Sanchez Lermen, Rafaela, Coral, Gabriela Perdomo, Paraná, Raymundo, Tovo, Cristiane Valle, Terrabuio, Débora Raquel Benedita, Filgueira, Norma Arteiro, de Paula Pessoa, Francisco Sergio Rangel, de Araújo, Fernando Antônio Barreiros, Strauss, Edna, Rocha, Cristina Melo, Ferreira, Paulo Roberto Abrão, and Ruffeil, Nilma Lucia Sampaio more...
- Abstract
Direct antiviral agents (DAAs) including sofosbuvir (SOF), daclatasvir (DCV), simeprevir (SIM) and ombitasvir, paritaprevir and dasabuvir were introduced 2015 in Brazil for treatment of hepatitis C virus (HCV) infection. The aims of this study were to assess effectiveness and safety of HCV treatment with DAA in real-life world in a highly admixed population from Brazil. more...
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- 2019
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32. Mapping the world’s free-flowing rivers
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Grill, G., Lehner, B., Thieme, M., Geenen, B., Tickner, D., Antonelli, F., Babu, S., Borrelli, P., Cheng, L., Crochetiere, H., Ehalt Macedo, H., Filgueiras, R., Goichot, M., Higgins, J., Hogan, Z., Lip, B., McClain, M. E., Meng, J., Mulligan, M., Nilsson, C., Olden, J. D., Opperman, J. J., Petry, P., Reidy Liermann, C., Sáenz, L., Salinas-Rodríguez, S., Schelle, P., Schmitt, R. J. P., Snider, J., Tan, F., Tockner, K., Valdujo, P. H., van Soesbergen, A., and Zarfl, C. more...
- Abstract
Free-flowing rivers (FFRs) support diverse, complex and dynamic ecosystems globally, providing important societal and economic services. Infrastructure development threatens the ecosystem processes, biodiversity and services that these rivers support. Here we assess the connectivity status of 12 million kilometres of rivers globally and identify those that remain free-flowing in their entire length. Only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length and 23 per cent flow uninterrupted to the ocean. Very long FFRs are largely restricted to remote regions of the Arctic and of the Amazon and Congo basins. In densely populated areas only few very long rivers remain free-flowing, such as the Irrawaddy and Salween. Dams and reservoirs and their up- and downstream propagation of fragmentation and flow regulation are the leading contributors to the loss of river connectivity. By applying a new method to quantify riverine connectivity and map FFRs, we provide a foundation for concerted global and national strategies to maintain or restore them. more...
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- 2019
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33. Kinetic studies on clinical and immunological modulations by intramuscular injection of Escherichia coliLPS in laying hens
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Liermann, Wendy, Frahm, Jana, Halle, Ingrid, Bühler, Susanne, Kluess, Jeannette, Hüther, Liane, and Dänicke, Sven
- Abstract
The present study investigated clinical and immunological modulations due to intramuscular injection of Escherichia coliLPS in 49-wk-old laying hens over 48 h post injection (p.i.). LPS induced characteristic sickness behavior but no significant body temperature alterations (P> 0.05). During experimental period decreases in blood albumin, calcium, phosphorus and tryptophan concentrations, hyperglycemia, increased plasma nitrite concentrations, leucopenia, decreased thrombocyte counts, lymphopenia, heterophilia and an increased heterophilic granulocyte/lymphocyte (H/L) ratio were observed after LPS administration. Time-dependent effects were shown on T and B cell subsets in caecal tonsils (CT) and on splenic CD3+/CD4+/CD8+proportions, on IL-1β and -10 and inducible NO synthase mRNA expression in peripheral blood lymphocytes (PBL), liver, spleen and CT, and on the mRNA expression of the TLR4 in PBL, liver and spleen p.i. (P< 0.05). The main responding period of mentioned alterations due to LPS appears to include the period from 2 until 8 h p.i. According to the H/L ratio, the most stressful phase was 5 h p.i. T and B cell subsets in CT, the IL-1β and TLR4 mRNA expression in liver and plasma nitrite concentrations seemed to be affected for a longer period. more...
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- 2019
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34. Chemoradiation in female patients with anal cancer: Patient-reported outcome of acute and chronic side effects
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Koerber, Stefan A., Seither, Ben, Slynko, Alla, Haefner, Matthias F., Krug, David, Liermann, Jakob, Adeberg, Sebastian, Herfarth, Klaus, Debus, Juergen, and Sterzing, Florian
- Abstract
Introduction: We evaluated acute and chronic side effects of 3D conformal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) in female patients with anal carcinoma and accessed correlations between dosimetric parameters and the considered toxicities.Methods: For 70 women with anal cancer treated at our department, acute and chronic side effects and quality of life (QoL) were evaluated with questionnaires using the Common Terminology Criteria for Adverse Events (CTCAE v. 4.0.) and Late Effects in Normal Tissue, Subjective, Objective Management and Analytic Scales (LentSoma) before, during, and after the treatment.Results: Forty-seven out of 70 (67%) patients completed the questionnaire and were enrolled in the study. Only poor urinary stream, loss of pubic hair during chemoradiation, and chronic vaginal dryness were observed more frequently in the 3D-CRT group compared to the IMRT group (univariable logistic regression p= .032, p= .04, p= .049, respectively). After the treatment, 43% in the 3D-CRT group and 29% in the IMRT group reported a severe loss of QoL. A higher proportion among the patients receiving a genital V20 ⩾35% showed grade 1–3 side effects such as chronic dyspareunia (p= .035; Fisher exact test).Conclusion: Our results suggest that the use of IMRT decreases acute and chronic adverse effects although reduced QoL also occurred in the IMRT group. These effects are likely to be underreported in retrospective studies using physician-reported outcome measures. more...
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- 2019
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35. Phase transition lowering in dynamically compressed silicon
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McBride, E. E., Krygier, A., Ehnes, A., Galtier, E., Harmand, M., Konôpková, Z., Lee, H. J., Liermann, H.-P., Nagler, B., Pelka, A., Rödel, M., Schropp, A., Smith, R. F., Spindloe, C., Swift, D., Tavella, F., Toleikis, S., Tschentscher, T., Wark, J. S., and Higginbotham, A. more...
- Abstract
Silicon, being one of the most abundant elements in nature, attracts wide-ranging scientific and technological interest. Specifically, in its elemental form, crystals of remarkable purity can be produced. One may assume that this would lead to silicon being well understood, and indeed, this is the case for many ambient properties, as well as for higher-pressure behaviour under quasi-static loading. However, despite many decades of study, a detailed understanding of the response of silicon to rapid compression—such as that experienced under shock impact—remains elusive. Here, we combine a novel free-electron laser-based X-ray diffraction geometry with laser-driven compression to elucidate the importance of shear generated during shock compression on the occurrence of phase transitions. We observe lowering of the hydrostatic phase boundary in elemental silicon, an ideal model system for investigating high-strength materials, analogous to planetary constituents. Moreover, we unambiguously determine the onset of melting above 14 GPa, previously ascribed to a solid–solid phase transition, undetectable in the now conventional shocked diffraction geometry; transitions to the liquid state are expected to be ubiquitous in all systems at sufficiently high pressures and temperatures. more...
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- 2019
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36. Novel High‐Pressure Potassium Chloride Monohydrate and Its Implications for Water‐Rich Planetary Bodies
- Author
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Wei, Xinmiao, Zhou, Qiang, Li, Fangfei, Zhang, Caizi, Sun, Fuxing, Zhang, Zihan, Li, Ruiyu, Yu, Hongyu, Yan, Yalan, Li, Liang, Liermann, Hanns‐Peter, Speziale, Sergio, and Li, Xinyang
- Abstract
Saline water is a common fluid on the Earth‘s surface and in ice planets. Potassium chloride (KCl) is a common salt and is expected to be a ubiquitous solute in salt water in the Universe; however, few studies investigated the behavior of KCl‐H2O system at high pressures and temperatures. In this study, powder and single‐crystal X‐ray diffraction (SC‐XRD), Raman and Brillouin scattering combined with diamond anvil cells were used to investigate the phase relation in the KCl‐H2O system for different KCl concentrations at 0–4 GPa and 298–405 K. The results of powder X‐ray diffraction and Raman scattering demonstrate that a novel KCl hydrate is formed when KCl aqueous solutions transform to solid ice‐VI and ice‐VII at high pressure. Simultaneously, the single‐crystal of KCl hydrate is synthesized from a supersaturated KCl solution at 298 K and 1.8 GPa. The structure is solved by SC‐XRD, indicating a KCl monohydrate with the P21/nspace group is formed. We have verified the phase stability of KCl monohydrate by using Raman spectroscopy and density functional theory. Our results indicate that KCl monohydrate is a stable phase under pressure and temperature conditions between 1.6 and 2.4 GPa and 298–359 K. By considering the thermal profile and composition of icy moons, we hypothesize that the formation and decomposition of KCl monohydrate might induce mantle convection in these moons. More and more evidence indicates that salt ions (Na+, Ca2+, Mg2+, K+, Cl−, and SO42−${\text{SO}}_{4}^{2-}$, etc.) could be dissolved in water and ices of the Earth‐like planets and water‐rich planets. The dissolution of alkali‐ and alkaline earth chlorides and sulfates in water and the incorporation of salt ions in the solid phases of H2O ices have a significant effect on their chemical and physical properties. Potassium chloride (KCl) is a ubiquitous salt in the Universe, and we investigated the phase relationship of the KCl‐H2O system for different KCl concentrations at pressures of 0–4 GPa and temperatures of 298–405 K. We were able to produce a single crystal of KCl monohydrate by adding KCl into a KCl‐saturated solution and pressurizing the solution at 1.8 GPa and 298 K. Our findings reveal the existence of a novel KCl monohydrate phase with monoclinic structure, which remains stable within the pressure and temperature range of 1.6–2.4 GPa and 298–359 K. Considering the thermal profile and composition of icy moons, our results suggest that the stability of the KCl monohydrate phase at pressures of 1.6–2.4 GPa and temperatures of 298–359 K may drive mantle convection through its formation and decomposition. A novel KCl monohydrate is synthesized in KCl‐H2O system at high pressuresStructure, phase stability, and density of KCl monohydrate are determined at high pressures and temperaturesKCl monohydrate formation and decomposition potentially drive mantle convection in icy moons A novel KCl monohydrate is synthesized in KCl‐H2O system at high pressures Structure, phase stability, and density of KCl monohydrate are determined at high pressures and temperatures KCl monohydrate formation and decomposition potentially drive mantle convection in icy moons more...
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- 2023
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37. Diel Shifts in Microhabitat Selection of Steelhead and Coho Salmon Fry.
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Hines, David, Liermann, Martin, Seder, Tiffany, Cluer, Brian, Pess, George, and Schoenebeck, Casey
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COHO salmon ,STEELHEAD trout ,ONCORHYNCHUS ,FISH communities ,FISH ecology - Abstract
Diel shifts in habitat selection of newly emerged steelheadOncorhynchus mykissand Coho SalmonO. kisutchfry were investigated in three northern California coastal watersheds. Steelhead and Coho Salmon fry occupied shallow water near stream margins during both day and night; however, the proportion of fry within 0.5 m of the stream margin increased from 6% during the day to 44% at night. Similarly, the proportion of fry in 10 cm of water or less increased from 26% during the day to 76% at night. Reductions in depth and distance to stream margins were significant at all sites, suggesting that these behaviors are common attributes for steelhead and Coho Salmon fry in this region. These results also suggest that newly emerged fry are potentially vulnerable to becoming stranded due to reductions in stream stage and water surface area, particularly at night. Although our observations were undertaken to better understand the risks to salmonids from vineyard water use for frost protection, the results have implications for any anthropogenic streamflow changes during the spring season. Received September 6, 2016; accepted June 3, 2017Published online August 9, 2017 [ABSTRACT FROM AUTHOR] more...
- Published
- 2017
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38. Relocation and Recolonization of Coho Salmon in Two Tributaries to the Elwha River: Implications for Management and Monitoring.
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Liermann, Martin, Pess, George, McHenry, Mike, McMillan, John, Elofson, Mel, Bennett, Todd, and Moses, Raymond
- Abstract
In 2012 the lower of two Elwha River dams was breached, restoring access of anadromous salmonids to the middle Elwha River (between the two dams), including two distinct tributaries, Indian Creek and Little River. While comparable in size, Indian Creek is considerably less steep than Little River (mean slope of 1.0% versus 3.5%, respectively) and has a warmer stream temperature regime due to its source, Lake Sutherland. During and after breaching, Coho SalmonOncorhynchus kisutchwere relocated to these tributaries from lower Elwha River hatcheries (below the dams) to determine if individuals from a hatchery-dominated population would successfully spawn and seed the systems with juveniles and to assess differences in recolonization between the streams. Transplantation led to immediate spawning, which resulted in levels of smolt out-migrants per stream kilometer comparable with other established Coho Salmon populations in the Pacific Northwest. During the first 2 years of the relocation, redd densities in the two systems were similar but Indian Creek produced four to five times as many smolts per kilometer as Little River. In addition, fry out-migration occurred 2 to 4 weeks earlier in Indian Creek, as predicted by the warmer incubation temperatures. In the first years of the study, there was little evidence of natural colonization of the two tributaries by adults. However, in 2016 over half of the observed adults returning to the two tributaries were not transplanted, suggesting that the progeny from the transplanted fish were returning to their natal waters. This work demonstrates that transplanting hatchery-dominated Coho Salmon adults into newly available habitat can result in immediate freshwater production that is comparable to other systems and that density and timing of juvenile out-migrants can differ dramatically based on the seeded habitat. Received December 9, 2016; accepted March 30, 2017 Published online July 28, 2017 [ABSTRACT FROM AUTHOR] more...
- Published
- 2017
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39. Distribution, Density, and Size of Migratory and Fluvial Sculpins in Relation to Barriers in Puget Sound Lowland Streams.
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Tabor, Roger A., Waterstrat, Frithiof T., Lantz, Daniel W., Berge, Hans B., and Liermann, Martin C.
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SCULPIN ,MIGRATORY fishes ,SIZE of fishes ,SPECIES distribution ,FISH habitats ,RIVER ecology - Abstract
We examined the effects of potential barriers on populations of migratory sculpins (Coastrange SculpinCottus aleuticusand Prickly SculpinC. asper) and fluvial sculpins (Riffle SculpinC. gulosus, Shorthead SculpinC. confusus, and Torrent SculpinC. rhotheus). Barriers can alter sculpin distribution because migratory sculpins have pelagic larvae that drift downstream to calm waters and juveniles and adults migrate upstream. We compared sculpin populations upstream and downstream of a barrier in 19 lowland streams in the Puget Sound region, Washington. Within each stream, we examined the farthest downstream barrier that would be most likely to impact the upstream movements of migratory sculpins. All study streams had populations of migratory sculpins in stream reaches downstream of the barrier. In 8 of the 19 streams with a barrier, at least one species of fluvial sculpin was also present. We also documented the relative distribution of migratory sculpins and fluvial sculpins in one reference stream without a barrier. In all streams examined, the density of migratory sculpins upstream of the barrier was lower than that downstream of the barrier and the differences were statistically significant. In 12 of the 19 streams, migratory sculpins were not present upstream of the barrier. In streams with fluvial sculpin populations, fluvial sculpins were usually rare downstream of barriers and were statistically less abundant than upstream of the barrier. The migratory sculpins collected upstream of barriers were statistically larger than those collected downstream of barriers. In the reference stream, migratory sculpin species dominated the lower stream reaches and were gradually replaced by fluvial sculpin species in more upstream reaches. Overall, barriers appear to have an important effect on the distribution of both migratory sculpins and fluvial sculpins, which should be taken into account when assessing habitat modifications and fish communities in Puget Sound lowland streams. Received November 4, 2016; accepted March 25, 2017 Published online June 12, 2017 [ABSTRACT FROM PUBLISHER] more...
- Published
- 2017
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40. Small hydropower goes unchecked.
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Lange, Katharina, Wehrli, Bernhard, Åberg, Ulrika, Bätz, Nico, Brodersen, Jakob, Fischer, Manuel, Hermoso, Virgilio, Liermann, Cathy Reidy, Schmid, Martin, Wilmsmeier, Lisa, and Weber, Christine
- Subjects
HYDROELECTRIC power plants ,HYDROELECTRIC power plants & the environment ,ELECTRIC power production ,SMALL scale hydropower ,TARIFF - Abstract
The article offers information on the less attention towards global boom of investment in small hydropower plants (SHPs). Topics discussed include information on the adverse impacts of large hydropower plants on nature and human livelihoods; discussions on the importance of the hydropower plants in generating the electric power; and the information on providing investment grants and feed-in tariffs in China provinces on SHPs. more...
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- 2019
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41. Elastic Softening of (Mg0.8Fe0.2)O Ferropericlase Across the Iron Spin Crossover Measured at Seismic Frequencies
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Marquardt, H., Buchen, J., Mendez, A. S. J., Kurnosov, A., Wendt, M., Rothkirch, A., Pennicard, D., and Liermann, H.‐P.
- Abstract
We experimentally determined the bulk modulus of (Mg0.8Fe0.2)O ferropericlase across the iron spin transition and in the low‐spin phase by employing a new experimental approach. In our measurements, we simulate the propagation of a compressional seismic wave (P wave) through our sample by employing a piezo‐driven dynamic diamond anvil cell that allows to oscillate pressure at seismic frequencies. During pressure oscillations, X‐ray diffraction images were continuously collected every 5–50 ms. The bulk modulus is directly calculated from these data at different pressures. Our experiments show a pronounced softening of the bulk modulus throughout the spin crossover, supporting previous single‐crystal measurements at very high frequencies and computations. Comparison of our results to previous data collected on (Mg,Fe)O with lower iron contents shows that the magnitude of softening strongly depends on iron content. Our experiments at seismic frequencies confirm that the iron spin crossover markedly affects the ratio of seismic compressional to shear wave velocities in Earth's lower mantle. Information about the structure and composition of Earth's mantle can be derived from comparison of measured seismic wave speeds to those predicted from laboratory sound wave velocity measurements at high pressures. Ferropericlase, the second most abundant mineral in Earth's lower mantle, changes its electronic configuration at pressures corresponding to the lower mantle. Laboratory measurements carried out at very high frequencies (GHz) indicate that this so‐called spin transition significantly decreases compressional wave velocities. If true, this effect can affect our interpretation of seismological observables. However, experimental results are partly in disagreement and no measurements have been conducted at typical seismic frequencies that are much lower as those typical for laboratory experiments. In this work. we directly measured the effect of the iron spin transition on the elastic response of ferropericlase at a frequency of 1 Hz. We find a significant softening effect on the bulk modulus that will lead to a decrease of compressional seismic velocities in Earth's lower mantle. Based on comparison of our results to previous work, we show that the effect strongly depends on iron content. We measured the bulk modulus softening across the spin transition in (Mg0.8Fe0.2)O ferropericlase at 1‐Hz frequencyResults agree with GHz‐frequency studies and show that softening scales with iron contentFindings show that the Vp/Vsratio is sensitive to the iron spin crossover in the lower mantle more...
- Published
- 2018
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42. Copolymerization Kinetics of Glycidol and Ethylene Oxide, Propylene Oxide, and 1,2-Butylene Oxide: From Hyperbranched to Multiarm Star Topology.
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Leibig, Daniel, Seiwert, Jan, Liermann, Johannes C., and Frey, Holger
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- 2016
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43. A role for subducted super-hydrated kaolinite in Earth’s deep water cycle
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Hwang, Huijeong, Seoung, Donghoon, Lee, Yongjae, Liu, Zhenxian, Liermann, Hanns-Peter, Cynn, Hyunchae, Vogt, Thomas, Kao, Chi-Chang, and Mao, Ho-Kwang
- Abstract
Water is the most abundant volatile component in the Earth. It continuously enters the mantle through subduction zones, where it reduces the melting temperature of rocks to generate magmas. The dehydration process in subduction zones, which determines whether water is released from the slab or transported into the deeper mantle, is an essential component of the deep water cycle. Here we use in situ and time-resolved high-pressure/high-temperature synchrotron X-ray diffraction and infrared spectra to characterize the structural and chemical changes of the clay mineral kaolinite. At conditions corresponding to a depth of about 75 km in a cold subducting slab (2.7 GPa and 200 °C), and in the presence of water, we observe the pressure-induced insertion of water into kaolinite. This super-hydrated phase has a unit cell volume that is about 31% larger, a density that is about 8.4% lower than the original kaolinite and, with 29 wt% H2O, the highest water content of any known aluminosilicate mineral in the Earth. As pressure and temperature approach 19 GPa and about 800 °C, we observe the sequential breakdown of super-hydrated kaolinite. The formation and subsequent breakdown of super-hydrated kaolinite in cold slabs subducted below 200 km leads to the release of water that may affect seismicity and help fuel arc volcanism at the surface. A super-hydrated clay mineral may play an important role in the solid Earth’s water cycle, according to laboratory experiments. The mineral kaolinite can carry and release large amounts of water during subduction. more...
- Published
- 2017
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44. Diel Shifts in Microhabitat Selection of Steelhead and Coho Salmon Fry
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Hines, David, Liermann, Martin, Seder, Tiffany, Cluer, Brian, Pess, George, and Schoenebeck, Casey
- Abstract
Diel shifts in habitat selection of newly emerged steelhead Oncorhynchus mykissand Coho Salmon O. kisutchfry were investigated in three northern California coastal watersheds. Steelhead and Coho Salmon fry occupied shallow water near stream margins during both day and night; however, the proportion of fry within 0.5 m of the stream margin increased from 6% during the day to 44% at night. Similarly, the proportion of fry in 10 cm of water or less increased from 26% during the day to 76% at night. Reductions in depth and distance to stream margins were significant at all sites, suggesting that these behaviors are common attributes for steelhead and Coho Salmon fry in this region. These results also suggest that newly emerged fry are potentially vulnerable to becoming stranded due to reductions in stream stage and water surface area, particularly at night. Although our observations were undertaken to better understand the risks to salmonids from vineyard water use for frost protection, the results have implications for any anthropogenic streamflow changes during the spring season. Received September 6, 2016; accepted June 3, 2017Published online August 9, 2017 more...
- Published
- 2017
- Full Text
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45. Relocation and Recolonization of Coho Salmon in Two Tributaries to the Elwha River: Implications for Management and Monitoring
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Liermann, Martin, Pess, George, McHenry, Mike, McMillan, John, Elofson, Mel, Bennett, Todd, and Moses, Raymond
- Abstract
AbstractIn 2012 the lower of two Elwha River dams was breached, restoring access of anadromous salmonids to the middle Elwha River (between the two dams), including two distinct tributaries, Indian Creek and Little River. While comparable in size, Indian Creek is considerably less steep than Little River (mean slope of 1.0% versus 3.5%, respectively) and has a warmer stream temperature regime due to its source, Lake Sutherland. During and after breaching, Coho Salmon Oncorhynchus kisutchwere relocated to these tributaries from lower Elwha River hatcheries (below the dams) to determine if individuals from a hatchery-dominated population would successfully spawn and seed the systems with juveniles and to assess differences in recolonization between the streams. Transplantation led to immediate spawning, which resulted in levels of smolt out-migrants per stream kilometer comparable with other established Coho Salmon populations in the Pacific Northwest. During the first 2 years of the relocation, redd densities in the two systems were similar but Indian Creek produced four to five times as many smolts per kilometer as Little River. In addition, fry out-migration occurred 2 to 4 weeks earlier in Indian Creek, as predicted by the warmer incubation temperatures. In the first years of the study, there was little evidence of natural colonization of the two tributaries by adults. However, in 2016 over half of the observed adults returning to the two tributaries were not transplanted, suggesting that the progeny from the transplanted fish were returning to their natal waters. This work demonstrates that transplanting hatchery-dominated Coho Salmon adults into newly available habitat can result in immediate freshwater production that is comparable to other systems and that density and timing of juvenile out-migrants can differ dramatically based on the seeded habitat.Received December 9, 2016; accepted March 30, 2017 Published online July 28, 2017 more...
- Published
- 2017
- Full Text
- View/download PDF
46. Diel Shifts in Microhabitat Selection of Steelhead and Coho Salmon Fry
- Author
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Hines, David, Liermann, Martin, Seder, Tiffany, Cluer, Brian, Pess, George, and Schoenebeck, Casey
- Abstract
AbstractDiel shifts in habitat selection of newly emerged steelhead Oncorhynchus mykissand Coho Salmon O. kisutchfry were investigated in three northern California coastal watersheds. Steelhead and Coho Salmon fry occupied shallow water near stream margins during both day and night; however, the proportion of fry within 0.5 m of the stream margin increased from 6% during the day to 44% at night. Similarly, the proportion of fry in 10 cm of water or less increased from 26% during the day to 76% at night. Reductions in depth and distance to stream margins were significant at all sites, suggesting that these behaviors are common attributes for steelhead and Coho Salmon fry in this region. These results also suggest that newly emerged fry are potentially vulnerable to becoming stranded due to reductions in stream stage and water surface area, particularly at night. Although our observations were undertaken to better understand the risks to salmonids from vineyard water use for frost protection, the results have implications for any anthropogenic streamflow changes during the spring season.Received September 6, 2016; accepted June 3, 2017Published online August 9, 2017 more...
- Published
- 2017
- Full Text
- View/download PDF
47. Relocation and Recolonization of Coho Salmon in Two Tributaries to the Elwha River: Implications for Management and Monitoring
- Author
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Liermann, Martin, Pess, George, McHenry, Mike, McMillan, John, Elofson, Mel, Bennett, Todd, and Moses, Raymond
- Abstract
In 2012 the lower of two Elwha River dams was breached, restoring access of anadromous salmonids to the middle Elwha River (between the two dams), including two distinct tributaries, Indian Creek and Little River. While comparable in size, Indian Creek is considerably less steep than Little River (mean slope of 1.0% versus 3.5%, respectively) and has a warmer stream temperature regime due to its source, Lake Sutherland. During and after breaching, Coho Salmon Oncorhynchus kisutchwere relocated to these tributaries from lower Elwha River hatcheries (below the dams) to determine if individuals from a hatchery-dominated population would successfully spawn and seed the systems with juveniles and to assess differences in recolonization between the streams. Transplantation led to immediate spawning, which resulted in levels of smolt out-migrants per stream kilometer comparable with other established Coho Salmon populations in the Pacific Northwest. During the first 2 years of the relocation, redd densities in the two systems were similar but Indian Creek produced four to five times as many smolts per kilometer as Little River. In addition, fry out-migration occurred 2 to 4 weeks earlier in Indian Creek, as predicted by the warmer incubation temperatures. In the first years of the study, there was little evidence of natural colonization of the two tributaries by adults. However, in 2016 over half of the observed adults returning to the two tributaries were not transplanted, suggesting that the progeny from the transplanted fish were returning to their natal waters. This work demonstrates that transplanting hatchery-dominated Coho Salmon adults into newly available habitat can result in immediate freshwater production that is comparable to other systems and that density and timing of juvenile out-migrants can differ dramatically based on the seeded habitat. Received December 9, 2016; accepted March 30, 2017 Published online July 28, 2017 more...
- Published
- 2017
- Full Text
- View/download PDF
48. Distribution, Density, and Size of Migratory and Fluvial Sculpins in Relation to Barriers in Puget Sound Lowland Streams
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Tabor, Roger A., Waterstrat, Frithiof T., Lantz, Daniel W., Berge, Hans B., and Liermann, Martin C.
- Abstract
We examined the effects of potential barriers on populations of migratory sculpins (Coastrange Sculpin Cottus aleuticusand Prickly Sculpin C. asper) and fluvial sculpins (Riffle Sculpin C. gulosus, Shorthead Sculpin C. confusus, and Torrent Sculpin C. rhotheus). Barriers can alter sculpin distribution because migratory sculpins have pelagic larvae that drift downstream to calm waters and juveniles and adults migrate upstream. We compared sculpin populations upstream and downstream of a barrier in 19 lowland streams in the Puget Sound region, Washington. Within each stream, we examined the farthest downstream barrier that would be most likely to impact the upstream movements of migratory sculpins. All study streams had populations of migratory sculpins in stream reaches downstream of the barrier. In 8 of the 19 streams with a barrier, at least one species of fluvial sculpin was also present. We also documented the relative distribution of migratory sculpins and fluvial sculpins in one reference stream without a barrier. In all streams examined, the density of migratory sculpins upstream of the barrier was lower than that downstream of the barrier and the differences were statistically significant. In 12 of the 19 streams, migratory sculpins were not present upstream of the barrier. In streams with fluvial sculpin populations, fluvial sculpins were usually rare downstream of barriers and were statistically less abundant than upstream of the barrier. The migratory sculpins collected upstream of barriers were statistically larger than those collected downstream of barriers. In the reference stream, migratory sculpin species dominated the lower stream reaches and were gradually replaced by fluvial sculpin species in more upstream reaches. Overall, barriers appear to have an important effect on the distribution of both migratory sculpins and fluvial sculpins, which should be taken into account when assessing habitat modifications and fish communities in Puget Sound lowland streams. Received November 4, 2016; accepted March 25, 2017 Published online June 12, 2017 more...
- Published
- 2017
- Full Text
- View/download PDF
49. Distribution, Density, and Size of Migratory and Fluvial Sculpins in Relation to Barriers in Puget Sound Lowland Streams
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Tabor, Roger A., Waterstrat, Frithiof T., Lantz, Daniel W., Berge, Hans B., and Liermann, Martin C.
- Abstract
AbstractWe examined the effects of potential barriers on populations of migratory sculpins (Coastrange Sculpin Cottus aleuticusand Prickly Sculpin C. asper) and fluvial sculpins (Riffle Sculpin C. gulosus, Shorthead Sculpin C. confusus, and Torrent Sculpin C. rhotheus). Barriers can alter sculpin distribution because migratory sculpins have pelagic larvae that drift downstream to calm waters and juveniles and adults migrate upstream. We compared sculpin populations upstream and downstream of a barrier in 19 lowland streams in the Puget Sound region, Washington. Within each stream, we examined the farthest downstream barrier that would be most likely to impact the upstream movements of migratory sculpins. All study streams had populations of migratory sculpins in stream reaches downstream of the barrier. In 8 of the 19 streams with a barrier, at least one species of fluvial sculpin was also present. We also documented the relative distribution of migratory sculpins and fluvial sculpins in one reference stream without a barrier. In all streams examined, the density of migratory sculpins upstream of the barrier was lower than that downstream of the barrier and the differences were statistically significant. In 12 of the 19 streams, migratory sculpins were not present upstream of the barrier. In streams with fluvial sculpin populations, fluvial sculpins were usually rare downstream of barriers and were statistically less abundant than upstream of the barrier. The migratory sculpins collected upstream of barriers were statistically larger than those collected downstream of barriers. In the reference stream, migratory sculpin species dominated the lower stream reaches and were gradually replaced by fluvial sculpin species in more upstream reaches. Overall, barriers appear to have an important effect on the distribution of both migratory sculpins and fluvial sculpins, which should be taken into account when assessing habitat modifications and fish communities in Puget Sound lowland streams.Received November 4, 2016; accepted March 25, 2017 Published online June 12, 2017 more...
- Published
- 2017
- Full Text
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50. Phytotherapeutics oridonin and ponicidin show additive effects combined with irradiation in pancreatic cancer in vitro
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Liermann, Jakob, Naumann, Patrick, Fortunato, Franco, Schmid, Thomas E., Weber, Klaus-Josef, Debus, Jürgen, and Combs, Stephanie E.
- Published
- 2017
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