4,394 research outputs found
Algorithm 830: Another Visit With Standard and Modified Givens Transformations and A Remark on Algorithm 539
First we report on a correction and improvement to the Level 1 Blas routine srotmg for computing the Modified Givens Transformation (MG). We then, in the light of the performance of the code on modern compiler/hardware combinations, reconsider the strategy of supplying separate routines to compute and apply the transformation. Finally, we show that the apparent savings in multiplies obtained by using MG rather than the Standard Givens Transformation (SG) do not always translate into reductions in execution time
A Study of Actor and Action Semantic Retention in Video Supervoxel Segmentation
Existing methods in the semantic computer vision community seem unable to
deal with the explosion and richness of modern, open-source and social video
content. Although sophisticated methods such as object detection or
bag-of-words models have been well studied, they typically operate on low level
features and ultimately suffer from either scalability issues or a lack of
semantic meaning. On the other hand, video supervoxel segmentation has recently
been established and applied to large scale data processing, which potentially
serves as an intermediate representation to high level video semantic
extraction. The supervoxels are rich decompositions of the video content: they
capture object shape and motion well. However, it is not yet known if the
supervoxel segmentation retains the semantics of the underlying video content.
In this paper, we conduct a systematic study of how well the actor and action
semantics are retained in video supervoxel segmentation. Our study has human
observers watching supervoxel segmentation videos and trying to discriminate
both actor (human or animal) and action (one of eight everyday actions). We
gather and analyze a large set of 640 human perceptions over 96 videos in 3
different supervoxel scales. Furthermore, we conduct machine recognition
experiments on a feature defined on supervoxel segmentation, called supervoxel
shape context, which is inspired by the higher order processes in human
perception. Our ultimate findings suggest that a significant amount of
semantics have been well retained in the video supervoxel segmentation and can
be used for further video analysis.Comment: This article is in review at the International Journal of Semantic
Computin
Couples\u27 Views of the Effects of Natural Family Planning on Marital Dynamics
Purpose: Natural Family Planning (NFP) requires periodic abstinence and partner cooperation to prevent pregnancy. The aim of this study was to learn about the effects of modern NFP methods on marital relationships. Design: Descriptive survey. Methods: Questionnaires were mailed to 1,400 randomly selected couples known to use NFP and residing in the United States of America; 334 couples (24%) responded. Content analysis was used to identify meanings and themes. Numeric analyses were used to determine frequencies. Findings: Nearly two-thirds of the qualitative comments were positive. Four themes were identified in the positive responses: relationship enhancements, knowledge improvements, spirituality enrichments, and method successes. Three negative themes were identified: strained sexual interactions, worsened relationships, and method problems. Although about onefourth of the comments indicated that NFP presented challenges, the majority (74%) found it beneficial, often resulting in stronger bonds, better communication, and improved knowledge. Conclusions: NFP had more positive than negative effects and its use warrants further consideration
Computing an interior point for inequalities using linear optimization
AbstractThe problem of finding the middle of a feasible region defined by solutions to a set of linear inequalities is considered. The solution of this problem is formulated as a primal-dual pair of linear optimization problems whose solutions can be obtained using linear programming computations
Expression studies on PPARγ in pancreatic neuroendocrine tumours
MDPancreatic NETs occur with an annual incidence of around 5 per 1,000,000 population
per year, with survival rates of between 30 – 97% at 5 years depending on the tumour
subtype. The PPARs (peroxisomal proliferator-activated receptors) are members of the
nuclear receptor superfamily that includes receptors for thyroid, steroid and retinoid
hormones. PPARγ protein is also thought to be expressed in human pancreatic islet cells
and has been shown to be a negative regulator of islet β cell mass both in vivo and in
vitro. Its emerging function in controlling cell proliferation, differentiation and
apoptosis, both in vivo and in vitro, has suggested a putative role as a tumour suppressor
gene.
I postulated that PPARγ is expressed in pancreatic neuroendocrine tumours and that
agonism with a thiazolidinedione will cause an anti-proliferative effect. Three different
types of tissue/cells were available to me: frozen human pancreatic neuroendocrine
tumours following surgical resection, paraffin-embedded samples held in the
histopathology archives, and human neuroendocrine tumour cell lines CM, BON and
QGP1 (insulinoma, carcinoid and somatostatinoma respectively).
PPARγ RNA was shown to be present in the majority of frozen surgical samples.
Immunohistochemistry for PPARγ protein on the paraffin-embedded samples, however,
revealed a lack of positive staining. These samples were then subjected to further
immunohistochemistry for detection of other potentially important proteins involved
with cellular proliferation including p27, phospho-p27, JAB1, PTEN and phospho-
AKT. In the tumour cell models, PPARγ RNA and protein was present in both BON
and QGP1. Proliferation studies following treatment doses of PPARγ agonist
3
rosiglitazone show a significant anti-proliferative effect. Recovery of cells was shown
following removal of treatment. However, inhibition of the effect was not achieved with
the use of PPARγ antagonists raising the possibility that the anti-proliferative effects of
thiazolidinediones may be independent of PPARγ
A Study of the Effects of Sustained Silent Reading on the Reading Attitudes and Habits of Second, Third, and Fourth Grade Students in a Low Income Area School
The Problem: The purpose of this investigation was to study the effects of the inclusion of a daily period of sustained silent reading in the classroom instructional program on the attitudes toward reading and the independent reading habits of second, third, and fourth graders in a low-income area school.
The Procedure: The sample for this investigation was comprised of children enrolled in twelve classrooms in Longfellox^ Elementary School, Great Falls, Montana. Four classrooms each, at second, third and fourth grade levels, participated in the study. Two experimental and two control group classrooms were identified at each grade level by a random selection process. The study began during the third week in September and ended during the third x^eek in March. Only those children who participated in the study for the entire treatment period were included in the final sample of 288 subjects.
The instruments used in this study were: the San Diego County Inventory of Reading Attitude, the Parent Survey: Children\u27s Reading In the Home, and the Reading Record Form. The pretest and posttest administration of the instruments was conducted by the researcher. The researcher also conducted in-service training sessions and made regular visits to all of the experimental and control group classrooms.
The experimental group classrooms provided a daily period of approximately thirty minutes of sustained silent reading during the six-month treatment period. The control group classrooms had a daily period, comparable in instructional time, of self-selected language activities.
The analysis of the data involved use of a one-way analysis of variance and one-way analysis of covariance. To test each of the six hypotheses, comparisons were made for the total sample and for each of the three grade level samples.
Conclusions: This study has provided evidence which supports the following conclusions, subject to the limitations of the study:
1. Providing children with a daily period of sustained silent reading for a six month period does not affect their expressed attitude toward reading. The findings indicate that experimental and control group children made comparable, positive gains in attitude toward reading during the treatment period.
2. Providing children v/ith a daily period of sustained silent reading for a six month period does not affect their out-of-school reading habits. The experimental and control group children in this study made comparable increases in the amount and variety of self- selected reading done in the home.
3. The inclusion of sustained silent reading in the reading program appears to have a positive effect on the independent reading habits of children. At two of the three grade levels involved in this study the children exposed to a daily period of sustained silent reading made significantly greater gains in independent reading than did control group children
Cost effective control of urban smog. A report of a conference held at the Federal Reserve Bank of Chicago, June 7-8, 1993
Environmental protection
Installment 2 of "Creating a Sustainable Food Future": Reducing Food Loss and Waste
Approximately one out of every four calories grown to feed people is not ultimately consumed by humans. Food is lost and wasted to a varying extent across the globe, across all stages of the food value chain, and across all types of food. As a result, overall global food availability is lower than it would be otherwise, negatively affecting food security and requiring the planet's agriculture system to produce additional food to compensate for the food that is not ultimately consumed by people. The potential benefits of reducing food loss and waste are large. As a strategy for closing the food gap between food available today and food needed in 2050 to adequately feed the planet's projected 9.3 billion people, reducing food loss and waste satisfies each of the development and environmental criteria we introduced in the first installment of the Creating a Sustainable Food Future series. While increasing food availability, reducing food loss and waste can alleviate poverty and provide gender benefits while reducing pressure on ecosystems, climate, and water. Reducing food loss and waste may be one of those rare multiple "win-win" strategies.How can the world go about reducing food loss and waste on a large scale? This installment of the forthcoming "World Resources Report Creating a Sustainable Food Future" addresses that question. This working paper, which will feed into that report, begins by clarifying definitions of food loss and waste, then quantifies the scale of the problem and explores the impact addressing the problem could have on the food gap. The paper then focuses on practical solutions for reducing food loss and waste and presents case studies of successful initiatives. It concludes by offering recommendations for how to scale up reductions in food loss and waste
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