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ZhangBoPHHSSensitivityAnalysisNon-Inferiority_SupportingInformation.pdf
No full textA major issue in non-inferiority trials is the controversial assumption of constancy,
namely that the active control has the same effect relative to placebo as in previous studies
comparing the active control with placebo. The constancy assumption is often in doubt, which
has motivated various methods that ‘discount’ the control effect estimate from historical data
as well as methods that adjust for imbalances in observed covariates. We develop a new
approach to deal with residual inconstancy, i.e. possible violations of the constancy assumption
due to imbalances in unmeasured covariates after adjusting for the measured covariates. We
characterize the extent of residual inconstancy under a generalized linear model framework and
use the results to obtain fully adjusted estimates of the control effect in the current study based
on plausible assumptions about an unmeasured covariate. Because such assumptions may
be difficult to justify, we propose a sensitivity analysis approach that covers a range of situations.
This approach is developed for indirect comparison with placebo and effect retention, and
implemented through additive and multiplicative adjustments.The approach proposed is applied
to two examples concerning benign prostate hyperplasia and human immunodeficiency virus
infection, and evaluated in simulation studies.Keywords: Constancy, Effect retention, Conditional effect, Putative placebo, Discounting, Active controlKeywords: Constancy, Effect retention, Conditional effect, Putative placebo, Discounting, Active controlKeywords: Constancy, Effect retention, Conditional effect, Putative placebo, Discounting, Active controlKeywords: Constancy, Effect retention, Conditional effect, Putative placebo, Discounting, Active contro
Preparation of vocational-technical teachers in selected community colleges
Full text linkThe increasing demand for vocational-technical training at the
community college level stems from four interrelated factors: the
impact of automation and technology, the rapid population increase,
he social awareness of the economic plight of minority groups, and
concern for the non-college-bound high school graduate or drop-out.
As a result, community colleges are increasing vocational-technical
programs, both in numbers and kinds.
The purpose of this study is to gather information about the
source, education, and work backgrounds of vocational-technical
teachers in community colleges in Oregon, Washington, and Northern
California.
The summary of studies and related materials reveals that
there is a shortage of qualified vocational-technical teachers. The
projected growth of community colleges' vocational-technical programs
will place more demands on the available supply of these
teachers. In order to meet present needs, community colleges are
actively recruiting teachers from other educational institutions,
business and industry, military retiree ranks, and from graduating
classes of colleges and universities.
Findings related to the purpose of this study reveal: The high
schools contribute the largest number of experienced teachers to
community colleges in the Pacific Northwest. Almost one-half of
the vocational-technical teachers in these colleges have taught less
than three years. Three-fourths of the teachers have been in their
present teaching position less than six years. Some of these teachers
have not graduated from high school--others have doctors degrees.
There is a need for uniform standards of education, related
work experience, and teacher preparation as a basis for certification
of vocational-technical teachers
Use of nondestructive spectroscopy to assess chlorophyll and nitrogen in fresh leaves
Full text linkFour aspects of factors influencing the accuracy of nondestructive chlorophyll (Chl) and nitrogen (N) measurement in fresh leaves were studied: (1) optimum wavelength (OW) identification; (2) indices development and evaluation; (3) influence of leaf properties; and (4) influence of meter parameters and sampling technique. Results were used to develop indices and prototype meters for Chl and N assessment. Our results indicated that the simple linear coefficient of determination (R2) between spectral reflectance or transmission and Chl or N in combination with spectral sensitivity was the most reliable method for determining the OW for Chl and N measurement in fresh leaves. There were two ranges of wavelengths, one in visible region (550 - 580 nm) and the other in the red edge region (700 - 730 nm), we determined that had the highest spectral sensitivity and largest R2 with smallest root mean square error over a wide-range of Chl concentrations (160 – 1188 µmol.m-2), and could be used as the OW to develop indices for Chl and N assessment. The OW in the red edge region could be used for Chl assessment across all species tested and the OW in the visible region could be used across anthocyanins-free species. The best indices were the indices developed with the Chl-related OW either from visible or red edge region in combination with a reference wavelength (RW) from the near infrared (NIR) region (750 – 1100 nm) that was sensitive to leaf texture but insensitive to Chl as the form of a simple ratio (RRW/ROW) or normalized difference vegetation index (RRW – ROW)/( RRW + ROW). With RW, the differences in reflectance in the visible and red edge regions caused by variation in leaf texture or other optical properties could be eliminated. This was particularly important when the R2 of a single-wavelength index was small for Chl or N measurement (e.g. R2<0.8000 for Chl or R2<0.6000 for N).
Parameters used by hand-held Chl meters (CCM-200, SPAD-502, and CM-1000) affected their accuracy for Chl and N assessment. Our results showed that SPAD-502 was more accurate than CCM-200 and CM-1000 for assessing Chl and N in fresh leaves. The Chl-sensitive wavelength used by CM-1000 (700 nm) was more accurate for estimating Chl than the wavelengths used by SPAD-502 (650 nm) and CCM-200 (660nm); however, we found that variation in sampling distance, orientation, light intensity, and the inconsistency of light intensity between ambient light sensor and the target leaf made the CM-1000 less accurate than the other two meters. Using the indices and OW determined through our research, we developed three prototype meters that were more accurate than or similar to the commercial hand-held meters in measuring Chl or N in fresh leaves. Among them, the prototype-III was more accurate than all the commercial hand-held meters for Chl and than the CM-1000 for N assessments across all the species we tested.Keywords: nondestructive, near infrared region, reference wavelength, 1st derivative, optimum wavelength, chlorophyll-insensitive wavelength, nitrogen, root mean square error, visible region, reflectance sensitivity, hand-held meter, chlorophyll-sensitive wavelength, assessment, wavelength, index, spectroradiometer, simple linear regression coefficient determination, chlorophyllKeywords: nondestructive, near infrared region, reference wavelength, 1st derivative, optimum wavelength, chlorophyll-insensitive wavelength, nitrogen, root mean square error, visible region, reflectance sensitivity, hand-held meter, chlorophyll-sensitive wavelength, assessment, wavelength, index, spectroradiometer, simple linear regression coefficient determination, chlorophyl
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No full textThis thesis is an effort to formalize and document some of the changes occuring in the Warwar Valley of Gongola State, Nigeria, West Africa. The documentation will comprise a photographic study over time accompanied by an ethnographic narrative. Information gathered from photographic images, field notes and the anthropological record will then be applied to a cultural-ecological model based on the theory of Julian Steward. The Mambilla people inhabiting the Warwar Valley are changing their traditional agricultural land use patterns and value system due to the influx of new ideas, notably the introduction of a cash economy. This cultural change has affected environmental change, observable in soil erosion
RobertaHall-Nepal.pdf
No full textRoberta Hall was part of an OSU [Oregon State University team that made exchange visits with women scholars in Nepal from 1995 through 1997. She spent Jan.-March of 1997 in Nepal and brought back extensive notes from observations and interviews; a bibliography on prehistory, current environmental problems, and women’s concerns; and 10 rolls of 35-mm slides. The program was sponsored by the office of Women in Development at OSU through a grant from the US Information Agency, primarily as a people-to-people program. Six Americans visited Nepal for two months each, and six Nepali women visited the US. This document is a report on many of Hall’s conversations, interviews, and notes on topics such as health and development, recycling, prehistory, and on Nepal’s diverse cultures. Before going to Nepal, Hall benefitted from lessons in the Nepali language and conversations with exchange scholars from Nepal
Subject Analysis, Library of Congress Classification, Part 2.ppt
No full textConsists of 12 PowerPoint presentations created for a course in subject analysis taught at Charles University, Prague, in 2005. Topics covered include subject heading construction, classification, shelf listing, and subject authority work, with emphasis on Library of Congress Subject Headings and Library of Congress Classification
PrahlFredrickCEOASBioticAbioticDegradationTable1.pdf
No full textLipid biomarkers in sediments are widely used to infer environmental conditions that have
occurred in the geological past, but these reconstructions require a careful consideration of the
biotic and abiotic processes that degrade and alter the lipid biomarker compositions before
and after deposition. In this paper, we use alkenones produced by haptophyte microalgae to
explore the range of effects of these degradative processes. Alkenones are now perhaps the
best studied of all biomarkers with several hundred papers on their occurrence in organisms,
seawater and sediments. Much information has been obtained on their degradation from
laboratory incubations and inferences from changes in their distribution in aquatic
environments. Although alkenones are often considered as more stable than many other lipid
classes, it is now clear that their distributions can be affected by processes such as prolonged
oxygen exposure, aerobic bacterial degradation and thiyl radical-induced stereomutation
processes which, in some cases, can lead to changes in the proportions of the alkenones used
in the U₃₇[superscript K′] temperature proxy. The same set of chemical and biological processes act on all
lipids in aquatic environments and, in cases where there is a marked difference in reactivity,
this may lead to significant changes in the biomarker distributions and relative proportions of
different lipid classes
LetelierRicardoCEOASPairedWindwardLeeward_SupportingInformation.zip
No full textSustained time series have provided compelling evidence for progressive acidification of the
surface oceans through exchange with the growing atmospheric reservoir of carbon dioxide. However,
few long-term programs exist, and extrapolation of results from one site to larger oceanic expanses is
hampered by the lack of spatial coverage inherent to Eulerian sampling. Since 1988, the Hawaii Ocean
Time-series program has sampled CO₂ system variables nearly monthly at Station ALOHA, a deep ocean site
windward and 115 km north of the island of Oahu. Surface measurements have also been made at Station
Kahe, a leeward site 12 km from the island and on the opposite side of the Hawaiian Ridge. Despite having
different physical settings, the sites exhibit identical rates of surface pCO₂ increase and hydrogen ion
accumulation, suggesting that atmospheric forcing dominates over local dynamics in determining the CO₂
trend in the surface waters of the North Pacific subtropical gyre.Keywords: Time series, Ocean acidification, Carbon cycle, Carbon dioxide, North Pacific subtropical gyreKeywords: Time series, Ocean acidification, Carbon cycle, Carbon dioxide, North Pacific subtropical gyreKeywords: Time series, Ocean acidification, Carbon cycle, Carbon dioxide, North Pacific subtropical gyreKeywords: Time series, Ocean acidification, Carbon cycle, Carbon dioxide, North Pacific subtropical gyr
