5,010 research outputs found
Community Response Strategies for Environmental Problems of Water Supply and Wastewater Disposal in Fairbanks, Alaska
This report examines the history of the response strategies of the
Fairbanks, Alaska, community to problems of water supply and wastewater
disposal. Fairbanks is significant since it is the largest settlement in
the northern subarctic and arctic regions of North America. Today, the
City of Fairbanks and the surrounding urban area have a combined population
of over 40,000
Environmental quality conditions in Fairbanks, Alaska, 1972
Published by
The Institute of Water Resources
and
The Institute of Social, Economic and Government Research
Fairbanks, AlaskaThis study represents a starting point for investigating the nature and interconnectivity of environmental quality problems in Fairbanks in the 1970's. Since the Fairbanks flood of 1967, no
detailed survey of environmental quality conditions has been conducted despite the impact of the flood, the considerable
expansion of the city limits, and the population expansion (anticipated and actual) associated with the oil pipeline.
The study focuses on selective aspects of environmental quality of continuing and increasing concern to Fairbanks area residents and also to the city and borough governments. Specifically, the issues
analyzed are (1) the environmental setting of the area, (2) structures, especially housing conditions, (3) premise conditions, and (4) waste control.
Much of the data was derived from a program called NEEDS, an acronym for Neighborhood Environmental Evaluation and Decision
System. NEEDS was developed by the Bureau of Community Environmental Management of the Department of Health, Education, and Welfare for rapid gathering of environmental, health,
and social information in urban areas.1 The NEEDS survey design consists of two separate stages. Stage I is concerned with collecting
general environmental quality information to determine geographically where the most pronounced environmental health problems exist in a given urban area. Stage II consists of detailed interviews with residents of the identified "problem areas" to determine the exact nature of existing health and environmental problems, e.g., housing, health, availability of services, and attitudes regarding existing government (local, state, and federal) programs.
With this information, local officials could begin to reorganize existing programs and/or develop new programs to solve some of the
interrelated environmental quality problems in the disadvantaged sections of their cities.The work upon which this report is based was
supported by funds provided by the State of
Alaska, the University of Alaska at Fairbanks, the United States Public Health Service, and the Office of Water Research and Technology
Recommended Sample Size for Conducting Exploratory Factor Analysis on Dichotomous Data
Minimum sample sizes are recommended for conducting exploratory factor analysis on dichotomous data. A Monte Carlo simulation was conducted, varying the level of communalities, number of factors, variable-to-factor ratio and dichotomization threshold. Sample sizes were identified based on congruence between rotated population and sample factor loadings
What is the diagnostic approach to a 1-year-old with chronic cough?
Very few studies examine the evaluation of chronic cough among young children. Based on expert opinion, investigation of chronic cough should begin with a detailed history, physical examination, and chest radiograph (strength of recommendation [SOR]: C, expert opinion). Before pursuing additional studies, remove potential irritants from the patient's environment. Work-up for persisting cough should consider congenital anomalies and then be directed toward common causes of chronic cough like those seen in older children and adults, including postnasal drip syndrome, gastroesophageal reflux disease (GERD), and asthma (SOR: C)
When should patients with mitral valve prolapse get endocarditis prophylaxis?
Patients with suspected mitral valve prolapse (MVP)should undergo echocardiography before any procedure that may place them at risk for bacteremia. Patients with MVP and documented absence of mitral regurgitation or valvular thickening likely do not need antibiotic prophylaxis against subacute bacterial endocarditis (SBE). Patients with MVP with documented mitral regurgitation, valvular thickening, or an unknown degree of valvular dysfunction may benefit from antibiotics during procedures that often lead to bacteremia (strength of recommendation: C)
Measuring the speed of light using beating longitudinal modes in an open-cavity HeNe laser
We describe an undergraduate laboratory that combines an accurate measurement
of the speed of light, a fundamental investigation of a basic laser system, and
a nontrivial use of statistical analysis. Students grapple with the existence
of longitudinal modes in a laser cavity as they change the cavity length of an
adjustable-cavity HeNe laser and tune the cavity to produce lasing in the
TEM mode. For appropriate laser cavity lengths, the laser gain curve of
a HeNe laser allows simultaneous operation of multiple longitudinal modes. The
difference frequency between the modes is measured using a self-heterodyne
detection with a diode photodetector and a radio frequency spectrum analyzer.
Asymmetric effects due to frequency pushing and frequency pulling, as well as
transverse modes, are minimized by simultaneously monitoring and adjusting the
mode structure as viewed with a Fabry-Perot interferometer. The frequency
spacing of longitudinal modes is proportional to the inverse of the cavity
length with a proportionality constant equal to half the speed of light. By
changing the length of the cavity, without changing the path length within the
HeNe gas, the speed of light in air can be measured to be ( m/s, which is to high enough precision to distinguish between
the speed of light in air and that in a vacuum.Comment: 6 pages; 6 figures; Published in the American Journal of Physic
Polyphenon E enhances the antitumor immune response in neuroblastoma by inactivating myeloid suppressor cells
This is the author's accepted manuscript. The final published article is available from the link below. Note: In this manuscript as well as in the original published version of this article the word "Polyphenon" was incorrectly spelled in the title as "Polyphenol."Purpose: Neuroblastoma is a rare childhood cancer whose high risk, metastatic form has a dismal outcome in spite of aggressive therapeutic interventions. The toxicity of drug treatments is a major problem in this pediatric setting. In this study, we investigated whether Polyphenon E, a clinical grade mixture of green tea catechins under evaluation in multiple clinical cancer trials run by the National Cancer Institute (Bethesda, MD), has anticancer activity in mouse models of neuroblastoma.
Experimental Design: We used three neuroblastoma models: (i) transgenic TH-MYCN mouse developing spontaneous neuroblastomas; (ii) nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice xenotransplanted with human SHSY5Y cells; and (iii) A/J mice transplanted with syngeneic Neuro 2A cells. Mice were randomized in control and Polyphenon E–drinking groups. Blood from patients with neuroblastoma and normal controls was used to assess the phenotype and function of myeloid cells.
Results: Polyphenon E reduced the number of tumor-infiltrating myeloid cells, and inhibited the development of spontaneous neuroblastomas in TH-MYCN transgenic mice. In therapeutic models of neuroblastoma in A/J, but not in immunodeficient NOD/SCID mice, Polyphenon E inhibited tumor growth by acting on myeloid-derived suppressor cells (MDSC) and CD8 T cells. In vitro, Polyphenon E impaired the development and motility of MDSCs and promoted differentiation to more neutrophilic forms through the 67 kDa laminin receptor signaling and induction of granulocyte colony-stimulating factor. The proliferation of T cells infiltrating a patient metastasis was reactivated by Polyphenon E.
Conclusions: These findings suggest that the neuroblastoma-promoting activity of MDSCs can be manipulated pharmacologically in vivo and that green tea catechins operate, at least in part, through this mechanism.SPARKS, Research in Childhood Cancer, the CGD
Research Trust, and the Wellcome Trust
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