329 research outputs found
How to Pick Your Man in Asia
Arthur M. Whitehill Professor of International Management at the University of Hawaii. He is also a member of the Affiliate Faculty of the Japan-America lnstitute of Management Science in Honolulu
Reactions of polycyclic aromatic hydrocarbon radical cations with model biological nucleophiles
The determination of gas-phase reactivity of a series of polycyclic aromatic hydrocarbons (PAHs) with nucleophiles is directed at achieving isomer differentiation through ion-molecule reactions and collisionally activated decomposition spectra. A series of PAH isomers form gas-phase [adduci — H]+ ions with the reagent nucleophiles pyridine and N-methylimidazole. Collisionally activated decomposition spectra of the [adduct — H]+ ions of the pyridine/PAH systems are dominated by products formed by losses of C5H4N, C5H5N (presumably neutral pyridine), and C5H6N. Collisional activation of PAH/N-methylimidazole [adduct — H]+ ions causes analogous losses of C4H5N2, C4H6N2 (presumably neutral N-methylimidazole), and C4H7N2. The relative abundances of the ions that result from these losses are highly isomer specific for N-methylimidazole but less so for pyridine. Furthermore, PAH/N-methylimidazole [adduct — H]+ ions undergo a series of metastableion decompositions that also provide highly isomer-specific information. The C4H7N2 (from PAH/N-methylimidazole product ions) and C5H6N (from PAH/pyridine product ions) losses tend to increase with the ΔHf of the PAH radical cation. In addition, it is shown that the fragmentation patterns of these gas-phase PAH/nucleophile adducts are similar to fragmentation patterns of PAH/nucleoside adducts generated in solution, which suggests that the structures of products formed in gas-phase reactions are similar to those produced in solution
Accessing gluon polarization with high- hadrons in SIDIS
A recent global QCD analysis of jet production and other polarized scattering
data has found the presence of negative solutions for the gluon helicity
distribution in the proton, , along with the traditional solutions. We consider polarized semi-inclusive deep-inelastic scattering
for hadrons produced with large transverse momentum as a means of constraining
the dependence of on the parton momentum fraction, . Focusing on
the double longitudinal spin asymmetry, we identify the kinematics relevant for
future experiments at Jefferson Lab and the Electron-Ion Collider which are
particularly sensitive to the polarized gluon channel and could discriminate
between the different behaviors.Comment: 22 pages, 7 figure
The Structure and Sensitivity of the Eye of Different Life History Stages of the Ontogenetic Migrator Gnathophausia ingens
The structure and ultrastructure of the photoreceptors of several life history stages of the ontogenetically migrating lophogastrid crustacean Gnathophausia ingens were examined. The younger instars of this species live in a much brighter light field than the older instars, and this difference is reflected in differences in their visual systems. The shallowest free living individuals (instars 3 and 4) possess a superposition eye with almost no clear zone, which minimizes the light shared between ommatidia and reduces the sensitivity of the eye. A progression to superposition optics with a large clear zone, usually associated with night-active or deep-living species, occurs as the animals move deeper in the water column. Regional differences within the eye are also evident, with a largely nonexistent clear zone in the dorsal region and a large clear zone in the ventral region in the eyes of instar 5 animals, the first instar to move to deeper depths. The deepest living instars (10–12) possess superposition optics with a large clear zone throughout the eye, and are significantly more sensitive to light than the younger, shallower instars
Effect of LSVT on Lexical Tone in Speakers with Parkinson's Disease
Lee Silverman Voice Treatment (LSVT) has well-documented treatment efficacy for individuals with hypokinetic dysarthria associated with Parkinson's disease (PD). Positive changes have been noted after treatment not only for vocal loudness but also for many other speech dimensions, including intonation (monotonicity). There have been few studies investigating the effect of LSVT on lexical tone which, like intonation, is controlled by variations in fundamental frequency. This study involved 12 Cantonese speakers with idiopathic PD who were enrolled in a standard LVST treatment protocol. Speech data were collected 3-4 days before treatment and 1 day after treatment. A wide variety of perceptual and acoustic variables were analyzed. The results showed significant improvements in loudness and intonation after treatment, but no significant changes in lexical tone. These results have theoretical implications for the relationship between tone and intonation and for models of the physiological control of fundamental frequency
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Incidence of Pediatric Cannabis Exposure Among Children and Teenagers Aged 0 to 19 Years Before and After Medical Marijuana Legalization in Massachusetts
Importance Pediatric health care contacts due to cannabis exposure increased in Colorado and Washington State after cannabis (marijuana) policies became more liberal, but evidence from other US states is limited.
Objective To document the incidence of pediatric cannabis exposure cases reported to the Regional Center for Poison Control and Prevention (RPC) before and after medical marijuana legalization (MML) in Massachusetts.
Design, Setting, and Participants Cross-sectional comparison of pediatric cannabis exposure cases 4 years before and after MML in Massachusetts. The exposure cases included those of 218 children and teenagers aged between 0 and 19 years, as reported to the RPC from 2009 to 2016. Census data were used to determine the incidence. Data analysis was performed from November 12, 2018, to July 20, 2019.
Exposure Cannabis products.
Main Outcomes and Measures Incidence of RPC-reported cannabis exposure cases, both single substance and polysubstance, for the age group of 0 to 19 years, and cannabis product type, coingestants, and clinical effects.
Results During the 8-year study period (2009-2016), the RPC received 218 calls involving cannabis exposure (98 single substance, 120 polysubstance) in children and teenagers aged 0 to 19 years, representing 0.15% of all RPC calls in that age group for that period. Of the total exposure cases, males accounted for 132 (60.6%) and females 86 (39.4%). The incidence of single-substance cannabis calls increased from 0.4 per 100 000 population before MML to 1.1 per 100 000 population after (incidence rate ratio, 2.4; 95% CI, 1.5-3.9), a 140% increase. The age group of 15 to 19 years had the highest frequency of RPC-reported cannabis exposures (178 calls [81.7%]). The proportion of all RPC calls due to single-substance cannabis exposure increased overall for all age groups from 29 before MML to 69 afterward. Exposure to edible products increased after MML for most age groups.
Conclusions and Relevance Pediatric cannabis exposure cases increased in Massachusetts after medical marijuana was legalized in 2012, despite using childproof packaging and warning labels. This study provides additional evidence suggesting that MML may be associated with an increase in cannabis exposure cases among very young children, and extends prior work showing that teenagers are also experiencing increased cannabis-related health system contacts via the RPC. Additional efforts are needed to keep higher-potency edible products and concentrated extracts from children and teenagers, especially considering the MML and retail cannabis sales in an increasing number of US states
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Trends and Characteristics of Manufactured Cannabis Product and Cannabis Plant Product Exposures Reported to US Poison Control Centers, 2017-2019
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