Secondhand Smoke Exposure and Preclinical Markers of Cardiovascular Risk in Toddlers

Objective: Links between secondhand smoke (SHS) exposure and cardiovascular disease in adults are well established but seldom reported during childhood. Although rates of smoking have decreased, young children from low-income backgrounds remain likely to be exposed to SHS. The purpose of this study was to investigate relationships between SHS exposure in young children and several preclinical markers of cardiovascular risk that have been established as relevant to adult populations. Methods: 139 children, 2–5 years of age, were enrolled in a cross-sectional study. SHS exposure was objectively determined by hair nicotine level; a comprehensive panel of clinical markers (AM blood pressure, fasting glucose & insulin, lipid profiles, inflammation) and research markers (markers of oxidation, endothelial stress, and endothelial repair) of cardiovascular risk status were assessed. Univariate and multivariate linear regression were used to evaluate relationships between SHS exposure and cardiovascular risk markers. Results: Hair nicotine levels were directly correlated with blood pressure and serum CRP, and inversely correlated with serum HDL and endothelial cell progenitor cell prevalence. In multivariate analyses, these relationships remained when controlled for age, sex, BMI z-score, maternal education, and method of payment. Additionally, in multivariate analyses, hair nicotine level was significantly negatively correlated with total anti-oxidant capacity. Conclusions: These results support the view that SHS exposure in the very young has a detectable relationship with several markers of cardiovascular risk, long before the emergence of clinical disease. Further studies to define mechanisms and strategies to prevent and mitigate these risks early in life are warranted

Millimeter-wave spectrum of 2-propanimine

Up to date, only 6 imines have been detected in the interstellar medium. The 3-carbon imine, 2-propanimine ((CH$_3$)$_2$C=NH), is predicted to be the structural isomer with the lowest energy in the C$_3$H$_7$N group, and appears to be a good candidate for astronomical searches. Unexpectedly, no microwave or millimeter wave spectrum is available for 2-propanimine. In this work, we provide the first high resolution millimeter wave spectrum of 2-propanimine and its analysis. With the guide of this laboratory measurement, we aim to search for 2-propanimine in two molecule-rich sources Sgr B2(N) and IRAS 16293-2422 using observations from the Atacama Large Millimeter/submillimeter Array (ALMA). Starting from a synthesized sample, we measured the spectrum of 2-propanimine from 50 to 500 GHz, and the ground state lines are successfully assigned and fitted using XIAM and ERHAM programs with the aid of theoretical calculations. The barriers to internal rotation of the two CH$_3$ tops are determined to be 531.956(64) cm$^{-1}$ and 465.013(26) cm$^{-1}$. These data are able to provide reliable prediction of transition frequencies for astronomical search. Although a few line matches exist, no confirmed detection of 2-propanimine has been found in the hot molecular core Sgr B2(N1S) and the Class 0 protostar IRAS 16293B. Upper-limits of its column density have been derived, and indicate that 2-propanimine is at least 18 times less abundant than methanimine in Sgr B2(N1S), and is at most 50-83 % of methanimine in IRAS 16293B.Comment: 14 pages, 10 figure

Using the Voice of the Student to Evaluate Learning Management Systems

A learning management system is an educational tool employed in higher education to organize, document, track, report, and deliver courses. Selecting the appropriate learning management system is a critical decision for a university. This study explores the usability of two leading systems, Blackboard and Canvas, from the students’ perspective. The goal is to gather and analyze user preferences in order to select an appropriate learning management system. Data was collected through surveys of student’s experience with the two learning management systems. The survey evaluated the ease of the following tasks: finding course documents, viewing grades, ease of navigation, intuitiveness, and communicating with professors. A usability study was also conducted on both learning management systems. The information was combined to provide an overall ranking of the learning management systems

Microwave, infrared and Raman spectra, r0 structural parameters, ab initio calculations and vibrational assignment of 1-fluoro-1-silacyclopentanea)

The microwave spectrum (6500–18 500 MHz) of 1-fluoro-1-silacyclopentane, c-C4H8SiHF has been recorded and 87 transitions for the 28Si, 29Si, 30Si, and 13C isotopomers have been assigned for a single conformer. Infrared spectra (3050-350 cm−1) of the gas and solid and Raman spectrum (3100-40 cm−1) of the liquid have also been recorded. The vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twist form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers to be saddle points with nearly the same energies but much lower energy than the planar conformer. By utilizing the microwaverotational constants for seven isotopomers (28Si, 29Si, 30Si, and four 13C) combined with the structural parameters predicted from the MP2(full)/6–311+G(d,p) calculations, adjusted r0 structural parameters have been obtained for the twist conformer. The heavy atom distances in Å are: r0(SiC2) = 1.875(3); r0(SiC3) = 1.872(3); r0(C2C4) = 1.549(3); r0(C3C5) = 1.547(3); r0(C4C5) = 1.542(3); r0(SiF) = 1.598(3) and the angles in degrees are: ∠CSiC = 96.7(5); ∠SiC2C4 = 103.6(5); ∠SiC3C5 = 102.9(5); ∠C2C4C5 = 108.4(5); ∠C3C5C4 = 108.1(5); ∠F6Si1C2 = 110.7(5); ∠F6Si1C3 = 111.6(5). The heavy atom ring parameters are compared to the corresponding rs parameters. Normal coordinate calculations with scaled force constants from MP2(full)/6–31G(d) calculations were carried out to predict the fundamental vibrational frequencies, infrared intensities, Raman activities, depolarization values, and infrared band contours. These experimental and theoretical results are compared to the corresponding quantities of some other five-membered rings

Culture shapes how we look at faces

Background: Face processing, amongst many basic visual skills, is thought to be invariant across all humans. From as early as 1965, studies of eye movements have consistently revealed a systematic triangular sequence of fixations over the eyes and the mouth, suggesting that faces elicit a universal, biologically-determined information extraction pattern. Methodology/Principal Findings: Here we monitored the eye movements of Western Caucasian and East Asian observers while they learned, recognized, and categorized by race Western Caucasian and East Asian faces. Western Caucasian observers reproduced a scattered triangular pattern of fixations for faces of both races and across tasks. Contrary to intuition, East Asian observers focused more on the central region of the face. Conclusions/Significance: These results demonstrate that face processing can no longer be considered as arising from a universal series of perceptual events. The strategy employed to extract visual information from faces differs across cultures

Ultrathin Oxide Films by Atomic Layer Deposition on Graphene

In this paper, a method is presented to create and characterize mechanically robust, free standing, ultrathin, oxide films with controlled, nanometer-scale thickness using Atomic Layer Deposition (ALD) on graphene. Aluminum oxide films were deposited onto suspended graphene membranes using ALD. Subsequent etching of the graphene left pure aluminum oxide films only a few atoms in thickness. A pressurized blister test was used to determine that these ultrathin films have a Young's modulus of 154 \pm 13 GPa. This Young's modulus is comparable to much thicker alumina ALD films. This behavior indicates that these ultrathin two-dimensional films have excellent mechanical integrity. The films are also impermeable to standard gases suggesting they are pinhole-free. These continuous ultrathin films are expected to enable new applications in fields such as thin film coatings, membranes and flexible electronics.Comment: Nano Letters (just accepted