Magnetism of Covalently Functionalized Carbon Nanotubes

We investigate the electronic structure of carbon nanotubes functionalized by adsorbates anchored with single C-C covalent bonds. We find that, despite the particular adsorbate, a spin moment with a universal value of 1.0 $\mu_B$ per molecule is induced at low coverage. Therefore, we propose a mechanism of bonding-induced magnetism at the carbon surface. The adsorption of a single molecule creates a dispersionless defect state at the Fermi energy, which is mainly localized in the carbon wall and presents a small contribution from the adsorbate. This universal spin moment is fairly independent of the coverage as long as all the molecules occupy the same graphenic sublattice. The magnetic coupling between adsorbates is also studied and reveals a key dependence on the graphenic sublattice adsorption site.Comment: final version, improved discussion about calculations and defect concentratio

Personal Problems Experienced in Conducting the Junior High Physical Education in Austin, Minnesota, and Some Recommended Solutions that Could Strengthen the Program

Austin, Minnesota, in light of present day evaluating procedures has an adequate program of physical education for boys of Junior High age. However, many problems confront the staff as the population explosion is at a near peak in the schools of Austin. This paper will attempt to discuss these problems that are evident and perplexing and will also make suggestions as to possible solutions of the problems. IN order to understand the Junior High School pupil, the author has made a study of this age group in order to give a true picture of the needs and interests of the Junior High child. There are many communities in this country with the same problems that we have in relationship to the physical education program in Austin. Our three main problems are: 1) lack of space both for activities and storage, 2) class size too large, and 3) time factor getting to and from a teaching station. A solution for all three of these problems would be to build a multi-purpose gymnasium which would give the needed space and would reduce the class size, as it would mean the addition of two or more teaching stations

Forbidden transitions in the helium atom

Nonrelativistically forbidden, single-photon transition rates between low lying states of the helium atom are rigorously derived within quantum electrodynamics theory. Equivalence of velocity and length gauges, including relativistic corrections is explicitly demonstrated. Numerical calculations of matrix elements are performed with the use of high precision variational wave functions and compared to former results.Comment: 11 pages, 1 figure, submitted to Phys. Rev.

The effects of the pre-pulse on capillary discharge extreme ultraviolet laser

In the past few years collisionally pumped extreme ultraviolet (XUV) lasers utilizing a capillary discharge were demonstrated. An intense current pulse is applied to a gas filled capillary, inducing magnetic collapse (Z-pinch) and formation of a highly ionized plasma column. Usually, a small current pulse (pre-pulse) is applied to the gas in order to pre-ionize it prior to the onset of the main current pulse. In this paper we investigate the effects of the pre-pulse on a capillary discharge Ne-like Ar XUV laser (46.9nm). The importance of the pre-pulse in achieving suitable initial conditions of the gas column and preventing instabilities during the collapse is demonstrated. Furthermore, measurements of the amplified spontaneous emission (ASE) properties (intensity, duration) in different pre-pulse currents revealed unexpected sensitivity. Increasing the pre-pulse current by a factor of two caused the ASE intensity to decrease by an order of magnitude - and to nearly disappear. This effect is accompanied by a slight increase in the lasing duration. We attribute this effect to axial flow in the gas during the pre-pulse.Comment: 4 pages, 4 figure

A Recreational Reading Program for Disabled Readers: It Works!

Much has been written about the desirability of turning disabled readers on to reading. Replacing negative feelings and disinterest which disabled readers typically have toward books is one of the most difficult tasks of all. But when disabled readers report little or no encouragement from home the challenge becomes even greater. Recent research has shown three very important factors in developing interest in reading-all three factors within the home: (1) fathers who read to children; (2) mothers who read to children and; (3) the availability of easy reading material in the home (Sucher, Note 1). When asked about reading habits and home involvement via the Literature Preference Inventory (Abrahamson and Stetson, Note 2), disabled readers tutored at the University of Houston Diagnostic Learning Center reported very little home involvement (Colvin and Tomas, 1978). A tabulation of student responses concerning home reading habits revealed that 85% of the mothers and 95% of the fathers seldom or never read to them. The prospects of turning these readers on to books did not look bright. The following paragraphs detail the Recreational Reading Program (RRP) implemented at the Diagnostic Learning Center in order to meet this challenge

Category 5

Follow Elizabeth and her family through this family oriented video series which highlights topics such as preparing for a hurricane, how to help those affected by a storm and raises awareness for mental health after a natural disaster. Nexus Maximus IV The Challenge: Innovation for Refugees and Displaced Populations One of the great challenges of our time is how to help refugees and displaced populations, and how to prevent the causes in the first place. Every minute, 24 people around the world are forced to flee their homes. That’s 34,000 people a day who leave everything behind in the hope of finding safety and a better tomorrow. The impact of war, political, racial and religious conflict, and environmental crises of famine and climate change, have caused great suffering and there is a great opportunity to do better. The issues these populations and the countries who receive them face are diverse and complex. They include public health, housing/built environment, cultural integration, public safety, employment/economic and more. How can innovation address these challenges? How do we create the social systems and products to support a healthy, safe and integrated program for refugees? How do we address the physical, emotional, and social needs of refugees to restore hope and opportunity? The solutions may be as far ranging as the challenges, exploring the acute needs during a crisis, as well as the chronic needs of the permanently displaced; looking at immigration and adjustments to new cultures. We encourage participants to draw upon all disciplines, from health professions to architecture, engineering to design, ethics, communication and every way of thinking we have, to find better ways to innovate on physical solutions, processes, policies, systems, and more. Recap of poster presentationshttps://jdc.jefferson.edu/nexusmaximus/1015/thumbnail.jp

Phylogeny, phylogenetic inference, and cranial evolution in pitheciids and Aotus

Pitheciids, one of the major radiations of New World monkeys endemic to South and Central America, are distributed in the Amazon and Orinoco basins, and include Callicebus, Cacajao, Chiropotes, and Pithecia. Molecular phylogenetics strongly support pitheciid monophyly, whereas morphological analyses infer a range of phylogenies including a sister relationship between Aotus and Callicebus. We collected geometric morphometric cranial data from pitheciids and Aotus, and used cranial data for distance-based phylogenetic analysis and tests of phylogenetic signal. Phylogenetic analyses of pitheciids were repeated with Lagothrix, Callimico, and Saimiri outgroups for Procrustes shape with and without Aotus based on the whole cranium and six anatomical regions. All phylogenetic signal tests were significant, and tree lengths were shortest and had the least morphological change over the phylogeny for Procrustes residuals from the cranial base and palate. The majority of phylogenetic analyses of Procrustes shape for pitheciids without Aotus supported the molecular phylogeny, and with Aotus included the majority inferred an Aotus–Callicebus clade, although three analyses with Callimico as outgroup supported the molecular phylogeny. The morphological similarity of Aotus and Callicebus is likely a mix of plesiomorphy, allometry, and homoplasy, and future phylogenetic inference of living and extinct platyrrhine taxa should consider the impact of these factors alongside outgroup selection and cranial region

Supplement to: Air concentrations of polybrominated diphenyl ethers (PBDEs) in 2002-2004 at a rural site in the Great Lakes

Atmospheric PBDEs were measured on a monthly basis in 2002-2004 at Point Petre, a rural site in the Great Lakes. Average air concentrations were 7.0 ± 13 pg m**-3 for the sum of 14BDE (excluding BDE-209), and 1.8 ± 1.5 pg m**-3 for BDE-209. Concentrations of 3 dominant congeners (i.e., BDE-47, 99, and 209) were comparable to previous measurements at remote/rural sites around the Great Lakes, but much lower than those at urban areas. Weak temperature dependence and strong linear correlations between relatively volatile congeners suggest importance of advective inputs of gaseous species. The significant correlation between BDE-209 and 183 implies their transport inputs associated with particles. Particle-bound percentages were found greater for highly brominated congeners than less brominated ones. These percentages increase with decreasing ambient temperatures. The observed gas/particle partitioning is consistent with laboratory measurements and fits well to the Junge-Pankow model. Using air mass back-trajectories, atmospheric transport to Point Petre was estimated as 76% for BDE-47, 67% for BDE-99, and 70% for BDE-209 from west-northwest and southwest directions. During the same time period, similar congener profiles and concentration levels were found at Alert in the Canadian High Arctic. Different inter-annual variations between Point Petre and Alert indicate that emissions from other regions than North America could also contribute PBDEs in the Arctic. In contrast to weak temperature effect at Point Petre, significant temperature dependence in the summertime implies volatilization emissions of PBDEs at Alert. Meanwhile, episodic observations in the wintertime were likely associated with enhanced inputs through long-range transport during the Arctic Haze period