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This paper presents the power electronics converters of an electric vehicle charging station that works as a DC microgrid with an AC grid interface. The interface converter is an interleaved bidirectional DC-AC converter that enables the V2G (vehicle-to-grid) application. Inside the microgrid, there are converters for managing power from the DC bus to the electrical vehicles (wireless charging type) and stationary battery banks – all bidirectional, too. To constitute the sustainable characteristic of the solution, a solar photovoltaic system is attached to the DC bus through a power electronics converter. The control methodology and experimental results from the proposed system with focus on the converters characteristics are presented. This manuscript highlights a noteworthy reduction in the total harmonic distortion for the injected grid current as well as enhanced stability during battery charging and discharging in both wired and wireless modes.

In this work, we describe diabetes prevalence and birth outcomes in a primarily First Nations obstetrical population in northwest Ontario.

Although calcium (Ca) precipitation may play a pathogenic role in atherosclerosis, information on temporal patterns of microcalcifications in human coronary arteries, their relation to expression of calcification-regulating proteins, and colocalization with iron (Fe) and zinc (Zn) is scarce. Human coronary arteries were analyzed post mortem with a proton microprobe for element concentrations and stained (immuno)histochemically for morphological and calcification-regulating proteins. Microcalcifications were occasionally observed in preatheroma type I atherosclerotic intimal lesions. Their abundance increased in type II, III, and IV lesions. Moreover, their appearance preceded increased expression of calcification-regulating proteins, such as osteocalcin and bone morphogenetic protein-2. In contrast, their presence coincided with increased expression of uncarboxylated matrix Gla protein (MGP), whereas the content of carboxylated MGP was increased in type III and IV lesions, indicating delayed posttranslational conversion of biologically inactive into active MGP. Ca/phosphorus ratios of the microcalcifications varied from 1.6 to 3.0, including amorphous Ca phosphates. Approximately 75% of microcalcifications colocalized with the accumulation of Fe and Zn. We conclude that Ca microprecipitation occurs in the early stages of atherosclerosis, inferring a pathogenic role in the sequel of events, resulting in overt atherosclerotic lesions. Microcalcifications may be caused by local events triggering the precipitation of Ca rather than by increased expression of calcification-regulating proteins. The high degree of colocalization with Fe and Zn suggests a mutual relationship between these trace elements and early deposition of Ca salts.

Although recent studies have analyzed Hepatitis C (HCV) infections in liver tissue by in situ hybridization (ISH), many of these studies have been of limited diagnostic utility because of the low copy numbers of HCV in formalin-fixed paraffin-embedded (FFPE) tissue and failure to correlate the ISH analysis with other methods of detecting HCV.

Describes how the anti-environmental movement is rallying its ranks to gut years of environmental progress. Several hundred organizations; Activists are industry-supported; Activities and publications; Ulterior motives. INSET: Groups to watch out for (names)..

Focuses on waste company proposals targeting Native American lands which are meeting with a growing pattern of resistance. Since 1988, at least 42 of the 360 tribes in the US have been approached, and 30 have rejected waste company proposals; The Bureau of Indian Affairs (BIA); Preparation of an environmental impact statement (EIS), costing upwards of $1 million.

Addresses federal research and education efforts concerning noise control that have stagnated. Staff in the Environmental Protection Agency's Office of Noise Abatement and Control today compared to the 1970s; Dismantling of the office; Statistics on those suffering from hearing loss and damage due to excessive noise; Physiological and psychological effects of noise; Warnings from National Institutes of Health; Organizations enforcing standards.

Herein, the conversion times of biomass pyrolysis are measured at temperatures between 450 and 550 °C and particle size fractions between 0 and 400 μm using a cyclonic thermogravimetric analyzer (TGA) device. Beech, spruce, and ash wood are investigated, as well as torrefied samples. The conversion time decreases with the increasing temperature from 7 to less than 1 s. The influence of the type of biomass on the conversion time is limited and only significant for low temperatures, when kinetics dominates the conversion process. A clear influence of the torrefaction process on the pyrolysis conversion time is noted and can be explained by the modified porosity of the biomass particles during the torrefaction process. Kinetic data are extracted from the conversion times, and a model is developed for a better interpretation of the measured results. The model shows good comparison with the experimental data and may also be used for design purposes of fast pyrolysis reactors. The cyclonic thermogravimetric analyzer (TGA) is an analysis device for measuring fast pyrolysis conversion times. Experiments with raw and torrefied woody biomass show conversion times between 0.5 and 7 s; these times are more significantly impacted by the torrefaction pretreatment than by the differences in biomass type. A model is constructed to explain these results.

Discusses the interest religious institutions are beginning to take in the environment, focusing on such leaders as the Reverend David Wilkinson. Using Christianity and Judaism to solve the environmental crisis; Donald B. Conroy and the Coalition on Religion and Ecology; Other religious environmentalists.

Presents letters to the editor referencing articles and topics discussed in previous issues. Comments of a reader on the article "Once More With Blood"; Feedback of a reader on an article related to political developments in Taiwan; "Formosa: Solidarity of Gloom," by Marilyn Young.

Considers the differences between children and adults when formulating risk assessments, making rulings on pesticides and rewriting clean air laws. Impact of growing environmental problems on the nation's young; Lead poisoning; Pesticide limits;Need for the revision of the air quality standards of the Environmental Protection Agency (EPA).

Deals with the suspicion that Kirtland Air Force Base in New Mexico is responsible for contaminating the water supply in Mountainview, N.Mex. SouthWest Organizing Project (SWOP), mobilized by Michael Guerrero, helped residents form the Mountainview Advisory Council that enabled citizens to work together with the Air Force, the Environmental Protection Agency, the state environmental department and the city of Albuquerque.

Focuses on the Savannah River nuclear weapons plant in North Carolina which opened in 1950. The nation's principle source of plutonium and tritium has shut down several reactors due to maintenance and operating problems. Opposition organized by Robert Randall with the group From Trident to Life and the Energy Research Foundation.

Estimates the scope of the damage of 600 Kuwaiti oil wells pouring smoke into the gulf region and beyond as a result of the Persian Gulf War. Length of time to extinguish the oil fields; Preliminary report on the health and environmental effects issued in April 1991 by the US government's interagency team, comprised of the Environmental Protection Agency (EPA), the National Oceanic and Atmospheric Administration and the Department of Health and Human Services.

Examines the cleanup of Pease Air Force Base in New Hampshire, the first of 86 military bases to be closed under a 1989 Congressional cost-cutting order. Closed March 31, 1991; Has over 20 chemically contaminated areas; Maine/New Hampshire Voice, the local activist group watchdogging the cleanup.

Discusses the exemption of certain military projects from requirements under the 1970 National Environmental Policy Act (NEPA). Agreement between Department of Defense (DOD) and White House Council on Environmental Quality brought about by Iraq'sinvasion of Kuwait. Impact on areas near Westover Air Force Base near Holyoke, Mass. and Fallon Naval Airstation near Reno, Nev.; Growing concerns of environmental groups.

Describes efforts by the Louisiana Coastal Wetlands Interfaith Stewardship Plan and the Coalition to Restore Coastal Louisiana to preserve the state's eroding wetlands. Rate of erosion; Sarah Schoeffler and Paul Kemp; Work involved.

Reports on the efforts of Father Edward Surges of the St. Rene Catholic Church in Chicago to stop the construction of an incinerator by the Sun Chemical Company. Gaining support through the church; Citizens Against Pollution; Work of Rev. Adolph Coleman.

Describes Big Green, a conglomeration of environmental legislation that has been voted down or vetoed by California's politicians over the years and is now on the November ballot as Proposition 128. Pesticides; Offshore oil drilling; Emissions reduction; Supporters; Competing initiatives.

Profiles Cyndy Maldonado and her appointment to her Local Emergency Planning Committee (LEPC), which analyzes hazards in the community and establishes emergency response plans for industrial accidents involving hazardous chemicals. The Right to Know Act calls for formation of LEPCs; Various problems plaguing LEPCs; Details.

Provides details on major legislation passed in the last year or currently pending in Congress concerning the military's environmental responsibility. Legislation includes: Federal Facilities Compliance Act; Right to Know; Defense Environmental Restoration Account; Strategic Environmental Research and Development Program.

Discusses the Army's proposed expansion of Fort Riley in Kansas by adding 82,000 acres, forcing the relocation of farms, schools, businesses and cemeteries. Opposition by the group Preserve Rural America formed by Kansan Bill Hanson.

Profiles Paul Coleman who began walking from Kingston, Ontario in June of 1990 and plans to reach Brazil in time for the United Nation's international conference on the environment in June 1992. Purpose is to raise awareness of the Amazon rainforests through fables and stories; Advocates U.N. sponsored international rainforests network and an independent center to study biological benefits.

Discusses the 1990 Student Environmental Action Coalition's (SEAC) national conference which was attended by 7,600 students at the University of Illinois in Champaign-Urbana. Event Dubbed Catalyst; Origins of the movement; Corporate accountability campaign.

Describes the efforts of Pat Brown and the Ecumenical Task Force of the Niagara Frontier to thwart the plans of the Love Canal Revitalization Agency calling for a reopening of the polluted area for housing. Lawsuits involved; Remaining hazards.

Reports on the work of Ahmadia Thomas, a minister at the Mt. Sinai Non-Denominational Church in Richmond, Calif., who is instrumental in the effort to force environmental responsibility onto Chevron's petrochemical and agricultural chemical plants. Help of West County Toxics Coalition; Involvement of Jesse Jackson.