Steric Effects of Alkyl Ammonium Salts on the Combustion of Exchanged Smectite Clays

Bomb calorimetry was explored as a new method for determining the cation exchange capacity (CEC) of clays. Smectite clays were modified with several alkyl ammonium salts varying in number of carbons and the spatial orientation of the carbons about the central nitrogen atom. The clays used, standards purchased from the Source Clay Repository, have CECs of 44, 80, 88, and 120 meq/100 g. Theoretically, the combustion energy of the organo-clays should be approximately the same for each salt. Any differences in energy would be due to the different structures of the salts and how they are oriented in the interlamellar region of the clay. The number of alkyl ammonium salts that bind to the negatively charged sites in the clay layers would represent the CEC of the clay. The orientation of the organic cation in the interlamellar region was examined using x-ray powder diffraction, which provides the spacing between the clay layers. The combustion energy data collected using bomb calorimetry was used to calculate the CEC of the clay by comparing the energy from the pure salts to determine the number of salt molecules intercalated into the clay. Since the pure salt and the clay have a one-to-one charge ratio, the number of salt molecules will directly represent the number of negatively charged sites on the clay which is the CEC of the clay

Examining Protective Factors That Promote Resilience Among Children With An Incarcerated Parent

Children of incarcerated parents (CIP) represent one of the most vulnerable, at-risk populations in the United States (Johnston, 1995). Best estimates suggests there are 2.7 million children with an incarcerated parents and African-American children are disproportionately represented at a figure of 1 in 9 children (Glaze & Maruschak, 2008). Much of the research attempting to understand this population and guide intervention efforts has employed a deficit-based approach, highlighting the plethora of adverse risk factors and negative outcomes associated with being the child of an incarcerated parent. This approach fails to acknowledge the presence of resilience inherent in these youth. The exploratory mixed methods research utilized in this project includes a quantitative (Study 1) and qualitative (Study 2) component. The two studies attempt to better understand protective factors and resilience in CIP. Situated in a strengths-based approach, the first study utilizes a multi-measure survey of CIP to examine the relationship between academic achievement, parent-child contact and subjective psychological well-being (a construct of resilience). Study 2 utilizes qualitative in-depth interviews with caregivers of CIP to further understand perceptions of how the preceding factors affect youth from the caregiver’s perspective. Findings from these two studies suggest mixed perceptions of parent-child contact as a protective factor that promote resilience in CIP. Implications from findings are explored and discussed

The Impact of the Gerhardt Decision on Marijuana Driving Cases

One of the major consequences of legalizing marijuana is that it can affect drivers on the roadways. Courts across the country are facing issues such as the applicability of the long established standard field sobriety test for alcohol-driving impairment to determine marijuana-driving impairment; the characteristics indicative of marijuana-driving impairment; and the blood nanogram concentration levels that establish marijuana-driving impairment. The Massachusetts Supreme Court was the first state Supreme Court out of the box to address these issues. On January 6, 2017, the Massachusetts Supreme Court heard oral arguments in the case of Commonwealth v. Gerhardt 1, which required the court to consider several novel questions

Ca II triplet spectroscopy of small magellanic cloud red giants. II. abundances for a sample of field stars

We have obtained metallicities of ∼360 red giant stars distributed in 15 Small Magellanic Cloud (SMC) fields from near-infrared spectra covering the Ca II triplet lines using the VLT + FORS2. The errors of the derived [Fe/H] values range from 0.09 to 0.35 dex per star, with a mean of 0.17 dex. The metallicity distribution (MD) of the whole sample shows a mean value of [Fe/H] = -1.00 ± 0.02, with a dispersion of 0.32 0.01, in agreement with global mean [Fe/H] values found in previous studies. We find no evidence of a metallicity gradient in the SMC. In fact, on analyzing the MD of each field, we derived mean values of [Fe/H] = -0.99 ± 0.08 and [Fe/H] = -1.02 ± 0.07 for fields located closer and farther than 4° from the center of the galaxy, respectively. In addition, there is a clear tendency for the field stars to be more metal-poor than the corresponding cluster they surround, independent of their positions in the galaxy and of the clusters' age. We argue that this most likely stems from the field stars being somewhat older and therefore somewhat more metal-poor than most of our clusters. © 2010. The American Astronomical Society.Fil: Parisi, Maria Celeste. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Geisler, Doug. Universidad de Concepción; ChileFil: Grocholski, A. J.. University of Florida; Estados Unidos. Space Telescope Science Institute; Estados UnidosFil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Sarajedini, A.. University of Florida; Estados Unido

SKILLED RIDERS MANAGE HORSE GAIT COMPLEXITY THROUGH A GAIT TRANSITION WHILST ALSO MAINTAINING STABLE HORSE-RIDER COORDINATION VARIABILITY

Equestrian riders aim to cue smooth transitions between horse gaits. This study aimed to investigate whether competitive horse rider (n=10) decrease horse gait regularity and increase horse-rider coordination variability in the region of a gait transition (n=6; both walk-trot, and trot-canter) relative to baseline walk, trot and canter. Resultant accelerations from IMUs affixed to the horse’s girth and rider’s pelvis were calculated. Horse gait regularity was quantified as multiscale sample entropy (MSSE) of the pelvis. Horse-rider coordination variability (Coordvar) was quantified as the standard deviation of the horse-rider continuous relative phase. Pre-transition MSSE did not increase; post-transition MSSE significantly decreased (paired t-tests; pvar were found. Therefore, horse gait or horse-rider Coordvar does not increase in a transition