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At low temperatures, <200 mK, the thermal flux through low-dimensional amorphous dielectric bars, <2 μm wide and 200 nm thick, is transported by a small number of low-order elastic modes. For long bars, L>400 μm, it is known that the conductance scales as 1/L, where L is the length, but for short bars, 1 μm< L <400 μm, the length dependence is poorly known. Although it is assumed that the transport must exhibit a diffusive to ballistic transition, the functional form of the transition and the scale size over which the transition occurs have not, to our knowledge, been measured. In this paper, we use ultra-low-noise superconducting Transition Edge Sensors to measure the heat flux through a set of SiNx bars to establish the characteristic scale size of the ballistic to diffusive transition. For bars supporting 6 to 7 modes, we measure a thermal elastic-wave attenuation length of 20 μm. The measurement is important because it sheds light on the scattering processes, which in turn are closely related to the generation of thermal fluctuation noise. Our own interest lies in creating patterned phononic filters for controlling heat flow and thermal noise in ultra-low-noise devices, but the work will be of interest to others trying to isolate devices from their environments and studying loss mechanisms in micro-mechanical resonators. [ABSTRACT FROM AUTHOR]

Forty-eight of 52 (92%) agencies contracted with the New York City Administration for Children's Services (ACS) responded to a survey about problematic sexualized behaviors (PSB) of children in different levels of care within the child welfare system. Results revealed that almost all agencies reported PSB within their foster boarding home and residential treatment centers. A majority of agencies perceived PSB to be a significant problem for which staff and families were not sufficiently trained. These findings highlight many avenues for advocacy, clinical intervention, and staff development. [ABSTRACT FROM AUTHOR]

Five reasons lead us to believe that much of cancer is environmentally related: 1. Beginning with the work of Yamagiwa and Ichikawa in 1915, cancer has been produced in the laboratory under the control of man. 2. The trends of cancer incidence (and mortality) have been sharply up in some cases (lung), and sharply down in others (stomach, uterine cervix). 3. There are large differences in cancer among different parts of the world, and within the United States. 4. Migrants from one part of the world to another take on the rates of the part of the world to which they migrate. 5. Removal of known causes from the environment has been followed by reduced cancer incidence. Environmental causes of cancer lie in both personal environment: cigarette smoking, use of alcohol, sexual habits, perhaps diet; and in the impersonal environment: industrial and occupational pollutants, water and air contaminants, pesticides, flame retardants, diet additives, drugs. A joint effort by persons and by governments can reduce the incidence of cancer. [ABSTRACT FROM AUTHOR]