Search results for "yield"
showing 10 items of 1338 documents
Synthesis of the phytohormone [11C]methyl jasmonate via methylation on a C18 Sep Pak? cartridge
2005
[11C]labeled (±)-methyl jasmonate was synthesized using a C18 Sep Pak™ at ∼100°C to sustain a solid-supported 11C-methylation reaction of sodium (±)-jasmonate using [11C]methyl iodide. After reaction, the Sep Pak was rinsed with acetone to elute the labeled product, and the solvent evaporated rendering [11C]-(±)-methyl jasmonate at 96% radiochemical purity. The substrate, (±)-jasmonic acid, was retained on the Sep Pak so further chromatography was unnecessary. Total synthesis time was 25 min from the end of bombardment (EOB) which included 15 min to generate [11C]methyl iodide using the GE Medical Systems PET Trace MeI system, 5 min for reaction and extraction from the cartridge, and 5 min …
Automated synthesis and purification of [18F]fluoro-[di-deutero]methyl tosylate
2013
Automated synthetic procedures of [ 18 F]fluoro-[di-deutero]methyl tosylate on a GE TRACERlab FX F-N module and a non-commercial synthesis module have been developed. The syntheses included azeotropic drying of the [ 18 F]fluoride, nucleophilic 18 F-fluorination of bis(tosyloxy)-[di-deutero]methane, HPLC purification and subsequent formulation of the synthesized [ 18 F]fluoro-[di-deutero]methyl tosylate (d2-[ 18 F]FMT) in organic solvents. Automation shortened the total synthesis time to 50min, resulting in an average radiochemical yield of about 50% and high radiochemical purity (>98%). The possible application of this procedure to commercially available synthesis modules might be of signi…
Oligo(1,4-phenylenepyrazole-3,5-diyl)s
2003
The bifunctional nucleophile methylhydrazine reacts in an alkaline medium in a regioselective mode with chalcones to yield 2-pyrazolines, which can be oxidized by DDQ to the corresponding 1H-pyrazoles. From oligo(chalcone)s this reaction yields cross-conjugated compounds with an alternating sequence of 1,4-disubstituted benzene rings and 3,5-disubstituted 1H-pyrazole rings. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Emission Taxes, Feed-in Subsidies and the Investment in a Clean Technology by a Polluting Monopoly
2019
The paper studies the use of emission taxes and feed-in subsidies for the regulation of a monopoly that can produce the same good with a technology that employs a polluting input and a clean technology. The second-best tax and subsidy are calculated solving a two-stage policy game between the regulator and the monopoly with the regulator acting as the leader of the game. We find that the second-best tax rate is the Pigouvian tax. The tax implements the efficient level of the dirty output but does not affect the total output. On the other hand, the subsidy leads to the monopoly to reduce the dirty output but also to increase the total output. This increase in total output may yield a larger …
Self-Enforcing International Environmental Agreements: Adaptation and Complementarity
2018
This paper studies the impact of adaptation on the stability of an international emission agreement. To address this issue we solve a three-stage coalition formation game where in the first stage countries decide whether or not to sign the agreement. Then, in the second stage, signatories (playing together) and non-signatories (playing individually) select their levels of emissions. Finally, in the third stage, each country decides on its level of adaptation non co-operatively. We solve this game for two models. For both, it is assumed that damages are linear with respect to emissions which guarantee that emissions are strategic complements in the second stage of the game. However, for the …
Milk production and physiological traits of ewes and goats housed indoor or grazing at different daily timing in summer
2009
During a 6 week trial in summer, 3 homogeneous groups, each consisting of 5 Comisana ewes and 5 Rossa Mediterranea goats, grazed watered forage resources during day (D) or night (N), or were housed indoor and supplied with mowed herbage (H). Maximum THI peaked at 94 at the end of July, and was almost constantly higher of 80. Milk yield was higher in N than in D and H goats, whereas N ewes produced more milk than H group, but their milk yield was higher than D ewes only in the period with the highest THI values. The lower urea in N goat milk, and the higher casein in N ewe milk, seem to indicate a better efficiency in dietary nitrogen utilization of night grazing animals. N ewes showed lower…
Loss in milk yield and related composition changes resulting from different levels of somatic cell count in Valle del Belice dairy sheep
2015
Mastitis is the most common and costly disease in the dairy industry and is responsible for several production effects. Mammary infections cause high somatic cell count (SCC) and severe damage to udder tissue and result in important losses of milk yield and quality, curd and cheese yields in dairy ewes. The aim of this study was to determine the effect of different levels of SCC on milk yield and composition in Valle del Belice dairy sheep. The original data set used for this study included 92,261 records of 6,763 ewes. Data were collected between 1994 and 2006 in 15 flocks. Test-day records of milk yield (MY), fat % (F%), protein % (P%), and SCC were collected following an A4 recording sch…
Effect of clenching on biomechanical response of human mandible and temporomandibular joint to traumatic force analyzed by finite element method
2013
Purpose: The purpose of the present study was to analyze the effect of clenching on the biomechanical response of human mandible and temporomandibular joint (TMJ) to traumatic force by the finite element (FE) method. Material and Methods: FE models of the mandible and the TMJ in resting and clenching positions were prepared. Distribution and magnitude of von Mises stress were analyzed by applying force as a point load in the symphyseal, canine, body and angle regions of the mandible. In addition, strain energy density (SED) at the articular disc and in posterior connective tissue of TMJ was analyzed. Results: In the resting position, von Mises stress was mainly concentrated at the condylar …
High-yield Production of Amyloid-β Peptide Enabled by a Customized Spider Silk Domain
2020
AbstractDuring storage in the silk gland, the N-terminal domain (NT) of spider silk proteins (spidroins) keeps the aggregation-prone repetitive region in solution at extreme concentrations. We observe that NTs from different spidroins have co-evolved with their respective repeat region, and now use an NT that is distantly related to previously used NTs, for efficient recombinant production of the amyloid-β peptide (Aβ) implicated in Alzheimer’s disease. A designed variant of NT from Nephila clavipes flagelliform spidroin, which in nature allows production and storage of β-hairpin repeat segments, gives exceptionally high yields of different human Aβ variants as a solubility tag. This tool e…
Photoinduced Formation Mechanism of the Thymine−Thymine (6−4) Adduct
2013
The photoinduced mechanism leading to the formation of the thymine-thymine (6-4) photolesion has been studied by using the CASPT2//CASSCF approach over a dinucleotide model in vacuo. Following light absorption, localization of the excitation on a single thymine leads to fast singlet-triplet crossing that populates the triplet (3)(nπ*) state of thymine. This state, displaying an elongated C(4)═O bond, triggers (6-4) dimer formation by reaction with the C(5)═C(6) double bond of the adjacent thymine, followed by a second intersystem crossing, which acts as a gate between the excited state of the reactant and the ground state of the photoproduct. The requirement of localized excitation on just …