Evaluating the Economic Impact of Countervailing Duties on United States Warm Water Shrimp Imports

Estimates of price and scale elasticities for U.S. consumed shrimp are derived using aggregate source country shrimp import data. It was assumed that supply was perfectly elastic and U.S. wholesalers determine the quantities imported from individual countries given the prices and preferences of U.S. consumers. Ex-ante analysis suggests that most countries levied with the countervailing duty experience declines in U.S. import demand while those countries not affected by the countervailing duty experience increases in import demand. Ex-post analysis shows the reverse to be true. Several countries impacted by the countervailing duty had increased import demand from the United States while Mexico, which was not affected by the countervailing duty, had decreased import demand. The results from aggregate level data suggest that imposing duties on specific companies within a country may not be effective if that company is not a monopoly producer or controls a significant share of the shrimp produced in that country.International Relations/Trade,

Hippocampal BDNF regulates a shift from flexible, goal-directed to habit memory system function following cocaine abstinence.

The transition from recreational drug use to addiction involves pathological learning processes that support a persistent shift from flexible, goal-directed to habit behavioral control. Here, we examined the molecular mechanisms supporting altered function in hippocampal (HPC) and dorsolateral striatum (DLS) memory systems following abstinence from repeated cocaine. After 3 weeks of cocaine abstinence (experimenter- or self-administered), we tested new behavioral learning in male rats using a dual-solution maze task, which provides an unbiased approach to assess HPC- versus DLS-dependent learning strategies. Dorsal hippocampus (dHPC) and DLS brain tissues were collected after memory testing to identify transcriptional adaptations associated with cocaine-induced shifts in behavioral learning. Our results demonstrate that following prolonged cocaine abstinence rats show a bias toward the use of an inflexible, habit memory system (DLS) in lieu of a more flexible, easily updated memory system involving the HPC. This memory system bias was associated with upregulation and downregulation of brain-derived neurotrophic factor (BDNF) gene expression and transcriptionally permissive histone acetylation (acetylated histone H3, AcH3) in the DLS and dHPC, respectively. Using viral-mediated gene transfer, we overexpressed BDNF in the dHPC during cocaine abstinence and new maze learning. This manipulation restored HPC-dependent behavioral control. These findings provide a system-level understanding of altered plasticity and behavioral learning following cocaine abstinence and inform mechanisms mediating the organization of learning and memory more broadly

Americans' psychological health trajectories: analyses of survey data from the intergenerational studies

'Survey data from the Intergenerational Studies are used here to examine two American generations' trajectories of psychological health. Original Intergenerational Studies members were born in either 1921 or 1929; their children were born between 1938 and 1982. Psychological health, measured via the self-report California Psychological Inventory, was assessed between 1954 and 2006 for the older generation and between 1983 and 2006 for the younger generation. The authors ask: What is the developmental path of psychological health for the older and younger generation, when data are analyzed separately, and what are the additional advantages of analyzing the two generations' data simultaneously? Application of longitudinal hierarchical linear modeling indicates that while data analyzed separately by generation are provocative, the additional advantages of analyzing data from both generations simultaneously are impressive: a more complex form of change was extracted, and valuable empirical estimates of generational differences in intercept, slope, and quadratic term were obtained.' (author's abstract

U.S. Demand for Source–Differentiated Shrimp: A Differential Approach

Estimates of price and scale elasticities for U.S. consumed shrimp are derived using aggregate shrimp data differentiated by source country. Own-price elasticities for all countries had the expected negative signs, were statistically significant, and inelastic. The scale elasticities for all countries were positive and statistically significant at the 1% level with only the United States and Ecuador having scale elasticities of less than one. For the most part, the compensated demand effects showed that most of the cross-price effects were positive. Our results also suggest that despite the countervailing duties imposed by the United States, shrimp demand was fairly stable.CBS, conditional demand, countervailing duty, imports, scale elasticity, shrimp, Agribusiness, Farm Management, Food Consumption/Nutrition/Food Safety, Production Economics, C32, D12, Q13, Q22,

A Comparative Study of Magnetic Fields in the Solar Photosphere and Chromosphere at Equatorial and Polar Latitudes

Besides their own intrinsic interest, correct interpretation of solar surface magnetic field observations is crucial to our ability to describe the global magnetic structure of the solar atmosphere. Photospheric magnetograms are often used as lower boundary conditions in models of the corona, but not data from the nearly force-free chromosphere. National Solar Observatory's (NSO) Synoptic Optical Long-term Investigations of the Sun VSM (Vector Spectromagnetograph) produces full-disk line-of-sight magnetic flux images deriving from both photospheric and chromospheric layers on a daily basis. In this paper, we investigate key properties of the magnetic field in these two layers using more than five years of VSM data. We find from near-equatorial measurements that the east-west inclination angle of most photospheric fields is less than about 12{\deg}, while chromospheric fields expand in all directions to a significant degree. Using a simple stereoscopic inversion, we find evidence that photospheric polar fields are also nearly radial but that during 2008 the chromospheric field in the south pole was expanding superradially. We obtain a spatially resolved polar photospheric flux distribution up to 80{\deg} latitude whose strength increases poleward approximately as cosine(colatitude) to the power 9-10. This distribution would give a polar field strength of 5-6 G. We briefly discuss implications for future synoptic map construction and modeling

Far-infrared observations of young clusters embedded in the R Coronae Austrinae and RHO Ophiuchi dark clouds

Multicolor far infrared maps in two nearby dark clouds, R Coronae Austrinae and rho Ophiuchi, were made in order to investigate the individual contribution of low mass stars to the energetics and dynamics of the surrounding gas and dust. Emission from cool dust associated with five low mass stars in Cr A and four in rho Oph was detected; their far infrared luminosities range from 2 far infrared luminosities L. up to 40 far infrared luminosities. When an estimate of the bolometric luminosity was possible, it was found that typically more than 50% of the star's energy was radiated longward of 20 micrometers. meaningful limits to the far infrared luminosities of an additional eleven association members in Cr A and two in rho Oph were also obtained. The dust optical depth surrounding the star R Cr A appears to be asymmetric and may control the dynamics of the surrounding molecular gas. The implications of the results for the cloud energetics and star formation efficiency in these two clouds are discussed

Demonstrating the impact of a distributed leadership approach in higher education

© 2017 Association for Tertiary Education Management and the LH Martin Institute for Tertiary Education Leadership and Management. Higher education is under pressure to advance from a singular focus on assessment of outputs (measurements) to encompass the impact (influence) of initiatives across all aspects of academic endeavour (research, learning and teaching, and leadership). This paper focuses on the implications of this shift for leadership in higher education. Demonstrating the impact of leadership in higher education requires taking a step beyond measuring the skills, behaviours, and achievements of individual leaders to demonstrating how universities can evaluate the impact of actions taken to build leadership capacity across the institution. The authors extend the outcome of empirical research into how a distributed leadership approach can be enabled and evaluated in Australian higher education–to analyse the effectiveness of these processes for both measuring output and assessing the impact and influence of practice

Taming Ambident Triazole Anions: Regioselective Ion-Pairing Catalyzes Direct N-Alkylation with Atypical Regioselectivity

Controlling the regioselectivity of ambident nucleophiles toward alkylating agents is a fundamental problem in heterocyclic chemistry. Unsubstituted triazoles are particularly challenging, often requiring inefficient stepwise protection–deprotection strategies and prefunctionalization protocols. Herein we report on the alkylation of archetypal ambident 1,2,4-triazole, 1,2,3-triazole, and their anions, analyzed by in situ ¹H/¹⁹F NMR, kinetic modeling, diffusion-ordered NMR spectroscopy, X-ray crystallography, highly correlated coupled-cluster computations [CCSD­(T)-F12, DF-LCCSD­(T)-F12, DLPNO-CCSD­(T)], and Marcus theory. The resulting mechanistic insights allow design of an organocatalytic methodology for ambident control in the <i>direct</i> N-alkylation of unsubstituted triazole anions. Amidinium and guanidinium receptors are shown to act as strongly coordinating phase-transfer organocatalysts, shuttling triazolate anions into solution. The intimate ion pairs formed in solution retain the reactivity of liberated triazole anions but, by virtue of highly regioselective ion pairing, exhibit alkylation selectivities that are completely inverted (1,2,4-triazole) or substantially enhanced (1,2,3-triazole) compared to the parent anions. The methodology allows direct access to 4-alkyl-1,2,4-triazoles (<i>rr</i> up to 94:6) and 1-alkyl-1,2,3-triazoles (<i>rr</i> up to 99:1) in one step. Regioselective ion pairing acts in effect as a noncovalent in situ protection mechanism, a concept that may have broader application in the control of ambident systems

A human embryonic kidney 293T cell line mutated at the Golgi -mannosidase II locus

Disruption of Golgi -mannosidase II activity can result in type II congenital dyserythropoietic anemia and can induce lupus-like autoimmunity in mice. Here, we isolate a mutant human embryonic kidney (HEK) 293T cell line, called Lec36, that displays sensitivity to ricin that lies between the parental HEK 293T cells, whose secreted and membrane-expressed proteins are dominated by complex-type glycosylation, and 293S Lec1 cells, which only produce oligomannose-type N-linked glycans. The stem cell marker, 19A, was transiently expressed in the HEK 293T Lec36 cells, and in parental HEK 293T cells with and without the potent Golgi -mannosidase II inhibitor, swainsonine. Negative-ion nano-electrospray ionization mass spectra of the 19A N-linked glycans from HEK 293T Lec36 and swainsonine-treated HEK 293T cells were qualitatively indistinguishable and, as shown by collision-induced dissociation spectra, dominated by hybrid-type glycosylation. Nucleotide sequencing revealed mutations in each allele of MAN2A1, the gene encoding Golgi -mannosidase II: a point mutation in one allele mapping to the active site and an in-frame deletion of twelve-nucleotides in the other. Expression of wild-type but not the mutant MAN2A1 alleles in Lec36 cells restored processing of the 19A reporter glycoprotein to complex-type glycosylation. The Lec36 cell line will be useful for expressing therapeutic glycoproteins with hybrid-type glycans and provides a sensitive host for detecting mutations in human MAN2A1 causing type II congenital dyserythropoietic anemia