| Todd\'s_Quantum_Intro A brief overview of quantum mechanics. |
| TYC_Physics_Workshops Information about workshops provided for two-year or community college physics teachers and the products of this project. |
| UMPERG__Minds-On_Physics_(MOP) A one-year curriculum for high-school physics. It is the result of a materials-development project supported by the National Science Foundation, and its design was guided by educational research findi |
| Web_Physics_Project A flexible low budget outlet for small volume, high quality, HTML-based curricular material. It provides a forum for physics educators to exchange curriculum ideas and resources that make use of web |
| West_Point_Bridge_Design_Contest Bridge design contest (using specialized software) run a service to education and as a tribute to the U.S. Military Academy's two hundred years of service to the United States of America. U.S. studen |
| The_World_of_Beams_(Both_Energy_and_Particle) Explores the nature of particle beams, laser beams, and related physics topics. |
| World_Year_of_Physics_2005 Plans to bring the excitement of physics to the public and inspire a new generation of scientists. Includes information about projects, events and Einstein, sources for teachers, downloads, internatio |
| Hydrogeology_Research_Group,_University_of_Tennessee,_Knoxville Conducts research on contaminant transport in groundwater and age-dating of groundwater. |
| Coalition_Opposed_to_PCB_Ash_in_Monroe_County,_Indiana Provides information concerning the problem related to PCB hazardous waste incinerator and landfill. Links to resources and research. |
| Dioxin_Facts Chlorine Chemistry Council provides information regarding dioxins, their release into the environment, and their effects on human health. |
| The_Dioxin_Home_Page Personal home page by Lewis A. Shadoff, Ph.D., discusses dioxins, furans, and similar toxic substances, including what they are and where they are found. |
| Dioxin_Threat A report on the technical and social implications of dioxin. |
| e_hormone__At_the_Cutting_Edge_of_Endocrine_Disruptor_Research_ Provide information about: upcoming conferences, the latest in research techniques and results, commentaries from distinguished scholars in the field, links to related news and stories. |
| Endocrine_Disrupters__Are_Synthetic_Hormones_Causing_Environmental_Chaos? Information from the Why Files about the endocrine system, effects of pesticides/PCBs/dioxins on wildlife and people, and prospects for action to resolve this concern. |
| Endocrine_Disrupting_Substances_in_the_Environment Canadian Environmental Corps offers PDF file on this subject. |
| Endocrine_Disruption_by_Estrogenic_Environmental_Pollutants Overview of a chapter by B. Rey de Castro from the book Environmental Medicine. |
| Endocrine_Disruptors_Low-Dose_Peer_Review Report evaluating the low dose effects and dose response relationships for endocrine disrupting chemicals in mammalian species that relate to human health. |
| Endocrine_Disruptors_Research_Initiative Describes the coordination of U.S. federal government efforts to examine the hypothesis that there are chemicals present in the environment of humans and wildlife that, by virtue of their ability to i |
| Endocrine/Estrogen_Letter Newsletter and comprehensive set of endocrine disrupter links. |
| Environmental_Toxins_and_Reproductive_Health_--_About_com Information and internet links related to the reproductive effects of dioxins and other environmental toxins. |
| Fox_River_Watch Provides information on the PCB pollution of the Fox River, Green Bay, Wisconsin and Lake Michigan including research on PCBs, history, health effects, toxicity, sediment remediation, dredging, cleanu |
| Hormonally_Active_Agents_in_the_Environment 1999 National Academy of Sciences report (1) examines the science behind the ominous prospect of "estrogen mimics" threatening health and well-being and (2) identifies research |
| The_Information_Site_on_Endocrine_Modulation This conservative, industry/government funded site provides very cautious interpretations of scientific findings about endocrine disruption. |
| International_POPs_Elimination_Network IPEN works for the global elimination of persistent organic pollutants. Information on PCBs (polychlorinated biphenyls) including health effects, international, national and local policy efforts, eli |
| Introduction_to_Hormone_Disrupting_Chemicals An introduction to the effects of hormone disrupting chemicals on man and the environment, and the response of governments and industry to this problem. Written for anyone interested in the subject. I |
| National_Toxicology_Program_Center_for_the_Evaluation_of_Risks_to_Human__Reproduction_(CERHR) Resource for the latest information about potentially hazardous effects of chemicals on human reproduction and development. |
| New_Studies_Confirm_Dangers_of_Atrazine,_a_Widely_Used_Agricultural_Weed-Killer NRDC website describes research suggesting the atrazine is a carcinogen and causes ual abnormalities in male frogs. |
| OECD_Endocrine_Disruptors_Assessment Part of the OECD Test Guidelines Programme, focused on reaching international agreement on the testing and assessment of chemicals with respect to their endocrine disrupting potential. |
| Our_Stolen_Future Provides updates about endocrine disruption created by man-made chemical contaminants that interfere with hormones in humans and wildlife. |
| PCB_Home_Page_at_EPA Provides information on Polychlorinated Biphenyls (PCB's). Background, resources and links to many topics. |
| Persistent_Organic_Pollutants_(POPs) These chemical substances persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment. From the United Nations Enviro |
| Phthalates_and_Human_Health__Demystifying_the_Risks_of_Plastic-softening_Chemicals Discusses human health concerns and public health benefits related to plasticizers, which are chemicals used to soften normally-rigid PVC, or polyvinyl chloride plastics. |
| Questions_and_Answers_About_Dioxins_and_Food_Safety Discusses dioxins in the food chain. |
| Thymus_Atrophy Abstract of study that investigated whether TCDD triggers apoptosis in thymocytes. |
| WWF_Endocrine_Disruptor_Information Papers and speeches on how hormone disruptors interfere with bio-chemical processes, and a suspected list of hormone disruptors. |
| Öko-Recherche Analyses of material flows of chemicals in the environment, including endocrine-disrupting industrial chemicals. |
| Weed_Killer_Deforms__Organs_in_Frogs,_Study_Finds New York Times report on University of California study that found that male frogs exposed to very low doses of atrazine are deficient in testosterone and can develop multiple organs. (Apri |
| Teens_Before_Their_Time With budding breasts and pubic hair, girls are developing earlier than ever. What's causing it? And what are the psychological effects? Time Magazine. (October 30, 2000) |
| Drug_Delivery,_Polymers,_Pulmonary Alternative drug delivery, pharmaceutical formulations, polymeric drug delivery, microspheres, pulmonary delivery |
| GALENOS-Network Consisting of university pharmaceutical departments and industrial partners. It aims to promote quality education and ongoing research in Biopharmaceutics, Pharmaceutical Technology and Advanced Drug |
Previous Story / Next Story / Volume 4 archive Phys. Rev. Lett. 83, 4053 (issue of 15 November 1999) Title and Authors 
RailwayTechnical Research Institute, Japan Faster than a speeding bullet? The maglev trains now under development in Japan have topped 550 km/h, and their high speeds may exacerbate the problem of tunnel noise. Research on the problem led to the demonstration of the first sound waves that travel long distances without distortion. Communications engineers want complex light signals to travel through long fiberoptic cables without changing shape, so they have been developing optical solitary waves--waveforms that travel long distances without distortion. But solitary sound waves are thought to be very difficult to produce because the properties of air don't seem to permit them. In the 15 November PRL a Japanese team demonstrates the first production of acoustic solitary waves in air, which they say could lead to the undistorted transmission of heat and other forms of energy, as well as the elimination of troublesome shock waves from train tunnels and air compressors.Any large disturbance in air--like a lightening bolt or even a high-speed train entering a tunnel--normally generates a traveling sound wave that changes shape as it propagates. If it doesn't dissipate first, the pulse eventually forms a shock wave--the thunder clap forms immediately in the case of lightening. Solitary waves in optical fibers maintain their shape because the material exhibits "dispersion," a speed of light that depends on frequency in just the right way. But the speed of sound in air is relatively independent of frequency, so solitary sound waves have been a great challenge.Over the last several years Nobumasa Sugimoto of the University of Osaka has developed a theory suggesting that adding extra branches to Japanese train tunnels would eliminate the formation of shocks, creating less severe waveforms instead. More recently he realized that, under more ideal conditions than those of a tunnel, the branching structure could theoretically support acoustic solitary waves. In their latest work, Sugimoto and his colleagues demonstrated solitary waves in a steel tube 7.4 m long and 8 cm in diameter. A sudden pressure pulse at one end quickly steepened into a shock wave, but when the team added over 100 small tubes branching from the main pipe, each leading to a ping-pong-ball-sized air pocket, the pulse profile remained constant as it traveled through the pipe. Just as Sugimoto's theory predicted, the air pockets caused the speed of sound to depend on frequency in a way that allowed the existence of solitary waves.Sugimoto explains that several types of heavy machinery, such as compressors, generate acoustic shocks which engineers consider to be a nuisance, but suppression of them is difficult. He suggests that modifications of the branched pipe concept might help in these designs. Sugimoto also imagines "heat pipes" for transferring heat or other forms of energy waves over long distances without distortion, although he is hesitant to discuss the details of those unpublished ideas.Jun-Ru Wu of the University of Vermont tried unsuccessfully to create acoustic solitary waves about 20 years ago, so he is impressed with the team's accomplishment. Although he can't name any specific applications for these waves, Wu is certain that engineers will come up with some. Experimental Demonstration of Generation and Propagation of Acoustic Solitary Waves in an Air-Filled Tube N. Sugimoto, M. Masuda, J. Ohno, and D. Motoi Phys. Rev. Lett. 83, 4053 (issue of 15 November 1999) Previous Story / Next Story / Volume 4 archive 
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