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Artificial lighting systems are transitioning from incandescent to compact fluorescent lamp (CPL) and light-emitting diode (LED) bulbs in response to the U.S. Energy Independence and Security Act and the EU Ecodesign Directive, which leads to energy savings and reduced greenhouse gas emissions. Although CFLs and LEDs ace more energy-efficient than incandescent bulbs, they require more metal-containing components. There is uncertainty about the potential environmental impacts of these components and whether special provisions must be made for their disposal at the end of useful life. Therefore, the objective of this study is to analyze the resource depletion and toxicity potentials from the metals in incandescent, CFL, and LED bulbs to complement the development of sustainable energy policy. We assessed the potentials by examining whether the lighting products are to be categorized as hazardous waste under existing U.S. federal and California state regulations and by applying life cycle impact-based and hazard-based assessment methods (note that "life cycle impact-based method" does not mean a general life cycle assessment (LCA) but rather the elements in LCA used to quantify toxicity potentials). We discovered that both CFL and LED bulbs are categorized as hazardous, due to excessive levels of lead (Pb) leachability (132 and 44 mg/L, respectively; regulatory limit: 5) and the high contents of copper (111 000 and 31 600 mg/kg, respectively; limit: 2500), lead (3860 mg/kg for the CFL bulb; limit: 1000), and zinc (34 500 mg/kg for the CPL bulb; limit: 5000), while the incandescent bulb is not hazardous (note that the results for CPL bulbs excluded mercury vapor not captured during sample preparation). The CFLS and LEDs have higher resource depletion and toxicity potentials than the incandescent bulb due primarily to their high aluminum, copper, gold, lead, silver, and zinc. Comparing the bulbs on an equivalent quantity basis with respect to the expected lifetimes of the bulbs, the CFLs and LEDs have 3-26 and 2-3 times higher potential impacts than the incandescent bulb, respectively. We conclude that in addition to enhancing energy efficiency, conservation and sustainability policies should focus on the development of technologies that reduce the content of hazardous and rare metals in lighting products without compromising their performance and useful lifespan. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) are advertised as environmentally friendly because they are energy efficient and mercury-free. This study aimed to determine if LEDs engender other forms of environmental and human health impacts, and to characterize variation across different LEDs based on color and intensity. The objectives are as follows: (i) to use standardized leachability tests to examine whether LEDs are to be categorized as hazardous waste under existing United States federal and California state regulations; and (ii) to use material life cycle impact and hazard assessment methods to evaluate resource depletion and toxicity potentials of LEDs based on their metallic constituents. According to federal standards, LEDs are not hazardous except for low-intensity red LEDs, which leached Pb at levels exceeding regulatory limits (186 mg/L; regulatory limit: 5). However, according to California regulations, excessive levels of copper (up to 3892 mg/kg; limit: 2500), Pb (up to 8103 mg/kg; limit: 1000), nickel (up to 4797 mg/kg; limit: 2000), or silver (up to 721 mg/kg; limit: 500) render all except low-intensity yellow LEDs hazardous. The environmental burden associated with resource depletion potentials derives primarily from gold and silver, whereas the burden from toxicity potentials is associated primarily with arsenic, copper, nickel, lead, iron, and silver. Establishing benchmark levels of these substances can help manufacturers implement design for environment through informed materials substitution, can motivate recyclers and waste management teams to recognize resource value and occupational hazards, and can inform policymakers who establish waste management policies for LEDs. [ABSTRACT FROM AUTHOR]

IntroductionThere are very few opportunities for long-term, comprehensive postgraduate education in developing countries because of fiscal and human resource constraints. Therefore, physiotherapists have little opportunity following graduation to advance their skills through the improvement of clinical reasoning and treatment planning and application.BackgroundTo address the need for sustainable advanced instruction in physiotherapy within the country, a postgraduate Residency program was initiated in Nairobi, Kenya in 2012. The mission of the program is to graduate advanced orthopedic practitioners who can lead their communities and local profession in the advancement of clinical care and education. Since its inception, six cohorts have been initiated for a total of 90 resident participants. In addition, six program graduates are being trained to continue the Residency program and are serving as teaching assistants for the on campus modules. This training will result in a self-sustaining program by 2020.DiscussionThe manual therapy Residency education model allowed for advancement of the participating physiotherapists professional development utilizing evidence-based practice. This was done without altering the current education system within the country, or accessing expensive equipment.Concluding remarksThe Residency program was developed and established with the cooperation of a local education institution and a non-profit corporation in the United States. This collaboration has facilitated the advancement of orthopedic clinical standards in the country and will, hopefully, one day serve an as a template for future programs.

We demonstrate a GaN/AlGaN photonic crystal thermal emitter supported by a semi-transparent low-refractive-index substrate for mid-wavelength infrared operation. The employment of the substrate increases the mechanical strength of the photonic crystal, and enables the fabrication of a large-area thermal emitter for high power operation. First, we numerically investigate the control of emission spectra of the GaN/AlGaN photonic crystal thermal emitters and found that nearly single-peak emission in the normal direction can be realized in spite of the lower and asymmetric refractive index contrast due to the existence of the substrate. Then we fabricate a GaN/AlGaN thermal emitter with an area of 3.4 mm × 3.4 mm on a sapphire substrate, and experimentally demonstrate narrowband thermal emission with a Q factor of 101 and an emission power of 25 mW/μm/sr at 800°C.