391 research outputs found

    Effects of Incorporation of Sainfoin (\u3ci\u3eOnobrychis viciafolia\u3c/i\u3e Scop.) with Cool Season Grasses on \u3ci\u3ein vitro\u3c/i\u3e Digestibility and CH4 Emission

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    Sainfoin (Onobrychis viciafolia Scop.) is an important non-bloating perennial leguminous forage. The tannins in sainfoin alter protein metabolism in the rumen and have been implicated in altering both nitrous oxide and methane emissions. However, the effect of sainfoin when mixed with cool-season forages is unknown. Therefore, in this study, we evaluated the in-vitro fermentation of sainfoin hay mixed with two other perennial cool-season forages, meadow bromegrass and orchardgrass at five ratios (0:100, 25:75, 50:50, 75:50, and 100:0). Data on dry matter disappearance (DMD), neutral detergent fiber disappearance (NDFD), gas production (GP) methane (CH4) emissions, and ammonia production were collected 48 h post incubation. Ruminal fluid was sourced from three heifers fed with forage hay. Incubations were conducted with and without PEG (polyethylene glycol) as PEG negates the biological activity of tannins. Sainfoin had a higher nutritive value than the other two grass species as evidenced by the higher proportion of total nitrogen and lower proportion of ADF and NDF. The change in DMD, ammonia-N, NDFD, GP, and CH4 emissions between sainfoin and grass only hay were 3.1, 9.2, -36.8, -1.76, and -1.2% respectively with the intermediate results for the mixture. The inclusion of sainfoin with cool-season grasses has positive effects on ruminal fermentation and lowered in vitro methane emissions as compared to grass alon

    Light-controlled reversible modulation of frontier molecular orbital energy levels in trifluoromethylated diarylethenes

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    Among bistable photochromic molecules, diarylethenes (DAEs) possess the distinct feature that upon photoisomerization they undergo a large modulation of their pelectronic system, accompanied by a marked shift of the HOMO/LUMO energies and hence oxidation/reduction potentials. The electronic modulation can be utilized to remote-control charge-as well as energy-transfer processes and it can be transduced to functional entities adjacent to the DAE core, thereby regulating their properties. In order to exploit such photoswitchable systems it is important to precisely adjust the absolute position of their HOMO and LUMO levels and to maximize the extent of the photoinduced shifts of these energy levels. Here, we present a comprehensive study detailing how variation of the substitution pattern of DAE compounds, in particular using strongly electron-accepting and chemically stable trifluoromethyl groups either in the periphery or at the reactive carbon atoms, allows for the precise tuning of frontier molecular orbital levels over a broad energy range and the generation of photoinduced shifts of more than 1 eV. Furthermore, the effect of different DAE architectures on the transduction of these shifts to an adjacent functional group is discussed. Whereas substitution in the periphery of the DAE motif has only minor implications on the photochemistry, trifluoromethylation at the reactive carbon atoms strongly disturbs the isomerization efficiency. However, this can be overcome by using a nonsymmetrical substitution pattern or by combination with donor groups, rendering the resulting photoswitches attractive candidates for the construction of remote-controlled functional systems

    Boehmite sorbs perrhenate and pertechnetate

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    Integrated Water Resources Management in Cities in the World: Global Challenges

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    This is the final version. Available on open access from Springer via the DOI in this recordData Availability: The authors declare that all the data supporting the findings of this study are included in its Supplementary Information.Water scarcity and accessibility remain persistently amongst the most prominent global challenges. Although there is a wide agreement among international organizations that Integrated Water Resources Management (IWRM) and water governance are key to overcome water-related challenges, global assessments of the progress made by cities is lacking. This paper for the first time analyses the challenges of water, wastewater, municipal solid waste and climate change in cities. We used empirical studies (125 cities) based on the City Blueprint Approach and developed a statistical estimation model to estimate IWRM performances of another 75 cities. These 200 cities in total represent more than 95% of the global urban population. This comprehensive global picture enables us to evaluate the existing gaps in achieving water-related Sustainable Development Goals (SDGs), in particular SDG 6 (clean water and sanitation) and SDG 11 (sustainable cities and communities). The best performing cities were Amsterdam and Singapore. Unfortunately, most cities do not yet manage their water resources wisely and are far from achieving the SDGs. For instance, targets regarding drinking water supply are still a challenge for many cities in Africa and Asia and challenges regarding sanitation are high in cities in Africa, Asia and Latin America. The same holds for solid waste management, climate adaptation, and people living in informal settlements. In another paper we will address the solution pathways to these global challenges

    Evaluation of the effect of ultrasonic degassing on components produced by low pressure die casting

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    Ultrasonic processing is known to be an efficient means of aluminium melt degassing with additional benefits of being economical and environment friendly. This paper describes the performance of ultrasonic degassing in preparing melt for low pressure die casting (LPDC). Efficiency of ultrasonic degassing is compared with conventional Ar rotary degassing by direct measurements of hydrogen concentration in the melt with a Foseco Alspek-H probe and by reduced pressure test in different stages of the casting process. Significant reduction in dross formation along with similar efficiency of hydrogen degassing was shown for ultrasonic degassing as compared with conventional Ar rotary degassing. Mechanical properties, microstructure and porosity level of the components produced by LPDC after both degassing techniques are determined. Results show that the components produced after ultrasonic degassing treatment have similar hardness, tensile properties, porosity level and microstructure as the components degassed with conventional Ar rotary degassing.The European Union’s Seventh Framework Program managed by the Research Executive Agency (REA;FP7/2007–2013) under grant agreement number 286344 (www.ultragassing.eu)

    Functional analysis of genes involved in the biosynthesis of isoprene in Bacillus subtilis

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    In comparison to other bacteria Bacillus subtilis emits the volatile compound isoprene in high concentrations. Isoprene is the smallest representative of the natural product group of terpenoids. A search in the genome of B. subtilis resulted in a set of genes with yet unknown function, but putatively involved in the methylerythritol phosphate (MEP) pathway to isoprene. Further identification of these genes would give the possibility to engineer B. subtilis as a host cell for the production of terpenoids like the valuable plant-produced drugs artemisinin and paclitaxel. Conditional knock-out strains of putative genes were analyzed for the amount of isoprene emitted. Differences in isoprene emission were used to identify the function of the enzymes and of the corresponding selected genes in the MEP pathway. We give proof on a biochemical level that several of these selected genes from this species are involved in isoprene biosynthesis. This opens the possibilities to investigate the physiological function of isoprene emission and to increase the endogenous flux to the terpenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate, for the heterologous production of more complex terpenoids in B. subtilis

    Published at Univ. of Calif

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    AbstrAct: New regulatory restrictions have been placed on the use of some second-generation anticoagulant rodenticides in the United States, and in some situations this action may be offset by expanded use of first-generation compounds. We have recently conducted several studies with captive adult American kestrels and eastern screech-owls examining the toxicity of diphacinone (DPN) using both acute oral and short-term dietary exposure regimens. Diphacinone evoked overt signs of intoxication and lethality in these raptors at exposure doses that were 20 to 30 times lower than reported for traditionally used wildlife test species (mallard and northern bobwhite). Sublethal exposure of kestrels and owls resulted in prolonged clotting time, reduced hematocrit, and/or gross and histological evidence of hemorrhage at daily doses as low as 0.16 mg DPN/kg body weight. Findings also demonstrated that DPN was far more potent in short-term 7-day dietary studies than in single-day acute oral exposure studies. Incorporating these kestrel and owl data into deterministic and probabilistic risk assessments indicated that the risks associated with DPN exposure for raptors are far greater than predicted in analyses using data from mallards and bobwhite. These findings can assist natural resource managers in weighing the costs and benefits of anticoagulant rodenticide use in pest control and eradication programs

    HIV therapy by a combination of broadly neutralizing antibodies in humanized mice

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    Human antibodies to human immunodeficiency virus-1 (HIV-1) can neutralize a broad range of viral isolates in vitro and protect non-human primates against infection. Previous work showed that antibodies exert selective pressure on the virus but escape variants emerge within a short period of time. However, these experiments were performed before the recent discovery of more potent anti-HIV-1 antibodies and their improvement by structure-based design. Here we re-examine passive antibody transfer as a therapeutic modality in HIV-1-infected humanized mice. Although HIV-1 can escape from antibody monotherapy, combinations of broadly neutralizing antibodies can effectively control HIV-1 infection and suppress viral load to levels below detection. Moreover, in contrast to antiretroviral therapy the longer half-life of antibodies led to control of viraemia for an average of 60 days after cessation of therapy. Thus, combinations of potent monoclonal antibodies can effectively control HIV-1 replication in humanized mice, and should be re-examined as a therapeutic modality in HIV-1-infected individuals
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