Elastic and Mechanical Properties of Human Dentin

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67340/2/10.1177_00220345580370041801.pd

Precision neutron interferometric measurements of the n-p, n-d, and n-3He zero-energy coherent neutron scattering amplitudes

We have performed high precision measurements of the zero-energy neutron scattering amplitudes of gas phase molecular hydrogen, deuterium, and $^{3}$He using neutron interferometry. We find $b_{\mathit{np}}=(-3.7384 \pm 0.0020)$ fm\cite{Schoen03}, $b_{\mathit{nd}}=(6.6649 \pm 0.0040)$ fm\cite{Black03,Schoen03}, and $b_{n^{3}\textrm{He}} = (5.8572 \pm 0.0072)$ fm\cite{Huffman04}. When combined with the previous world data, properly corrected for small multiple scattering, radiative corrections, and local field effects from the theory of neutron optics and combined by the prescriptions of the Particle Data Group, the zero-energy scattering amplitudes are: $b_{\mathit{np}}=(-3.7389 \pm 0.0010)$ fm, $b_{\mathit{nd}}=(6.6683 \pm 0.0030)$ fm, and $b_{n^{3}\textrm{He}} = (5.853 \pm .007)$ fm. The precision of these measurements is now high enough to severely constrain NN few-body models. The n-d and n-$^{3}$He coherent neutron scattering amplitudes are both now in disagreement with the best current theories. The new values can be used as input for precision calculations of few body processes. This precision data is sensitive to small effects such as nuclear three-body forces, charge-symmetry breaking in the strong interaction, and residual electromagnetic effects not yet fully included in current models.Comment: 6 pages, 4 figures, submitted to Physica B as part of the Festschrift honouring Samuel A. Werner at the International Conference on Neutron Scattering 200

The Other Side of Through: Young Breast Cancer Survivors’ Spectrum of Sexual and Reproductive Health Needs

The long-term reproductive health impact of cancer treatments is a concern for premenopausal women with a history of breast cancer. This study examined the unmet sexual and reproductive health needs of breast cancer survivors, as well as concordances and discordances in needs by childbearing status and race. We interviewed 17 women diagnosed with breast cancer between the ages of 18 and 45 years and living in North Carolina. To analyze these data, we used the Sort and Sift, Think and Shift© method, a multidimensional qualitative analysis approach. We learned that breast cancer survivors (a) received limited reproductive health information, (b) desired realistic expectations of conceiving postcancer, (c) struggled with adjusting to their altered physical appearance, and (d) had menopause symptoms that led to sexual health and quality of life issues. Breast cancer survivors are in need of and desire more education and resources to address their sexual and reproductive health concerns

Learning to collaborate: Can young children develop better communication strategies through collaboration with a more popular peer

Unpopular children are known to have poor communication skills and experience difficulty in collaborative situations. This study investigated whether pairing unpopular, 5 to 6 year-old, children with a more popular peer would promote more effective collaboration. The study also investigated differences in popular and unpopular children's verbal and non-verbal communication. Thirty-six girls and 36 boys were placed in one of 12 popular, 12 unpopular or 12 mixed pairs. There were no mixed gender pairs. Children were filmed playing a collaborative game. Collaboration in popular pairs was more successful and less disputational than in unpopular pairs. Boys in unpopular pairs broke the rules of the game more often, argued more and did not monitoring their partners' facial expressions effectively. With popular partners they argued less, were more likely to elaborate disagreements, looked at their partner for longer, smiled more and were more likely to offer him a small toy. Unpopular girls' interactions were not markedly disruptive but they clearly benefited from being paired with a child with good communication skills. Popular girls modified their behaviour to take into account an unpopular partner's need for support. These findings suggest that pairing popular and unpopular children may be a useful classroom organisation strategy

Self-organized model of cascade spreading

We study simultaneous price drops of real stocks and show that for high drop thresholds they follow a power-law distribution. To reproduce these collective downturns, we propose a minimal self-organized model of cascade spreading based on a probabilistic response of the system elements to stress conditions. This model is solvable using the theory of branching processes and the mean-field approximation. For a wide range of parameters, the system is in a critical state and displays a power-law cascade-size distribution similar to the empirically observed one. We further generalize the model to reproduce volatility clustering and other observed properties of real stocks.Comment: 8 pages, 6 figure

An experimental investigation of laser scabbling of concrete

Laser scabbling of concrete is the process of removal of surface material using a high power laser beam. The main aim of this investigation was to establish an experimental procedure for assessing the effects of various parameters that may be critical for the effectiveness of the process, such as material composition and initial moisture content. The study shows that the key characteristics of the process can be detected by monitoring surface temperature variations. This experimental procedure is used to provide data on the effects of each parameter to explain the mechanisms that drive the process. The results suggest that scabbling is mainly driven by pore pressures in the cement paste, but strongly affected by other factors. Reducing permeability by adding PFA to the cement paste resulted in significant increase in volume removal; but reducing moisture content by air-drying of the material did not result in the expected reduction in volume removal