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190,090 full-text articles. Page 4577 of 4718.

Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi 2010 Laval University, Quebec City, Canada

Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi

Fathi Habashi

Water a component of the Four Elements considered by the ancient philosophers as essential for survival, played, and is still playing an essential role in society. Great civilizations in ancient times developed along great rivers. The ancient peoples knew how to manage water supplies by digging canals, controlling floods, and using water for irrigation. They designed equipment that used water to measure the time, to determine the density of solids, to fight fires, and to create vacuum. Modern engineers exploited water flow to design and construct huge hydroelectric power stations. Waterways and navigation systems were also an essential element for ...


Dispersal Of Stable Flies (Diptera: Muscidae) From Larval Developmental Sites., David B. Taylor, Roger D. Moon, Jack B. Campbell, Dennis R. Berkebile, Philip J. Scholl, Alberto B. Broce, Jerome A. Hogsette 2010 University of Minnesota - Twin Cities

Dispersal Of Stable Flies (Diptera: Muscidae) From Larval Developmental Sites., David B. Taylor, Roger D. Moon, Jack B. Campbell, Dennis R. Berkebile, Philip J. Scholl, Alberto B. Broce, Jerome A. Hogsette

David B Taylor

Seven mark-recapture studies were conducted over 3 yr to assess dispersal of newly emerging adult stable flies, Stomoxys calcitrans L., from larval development sites in a mixed agricultural environment in northeastern Nebraska. Infested hay debris piles were marked by dusting their surfaces with fluorescent pigments, adults were captured with surrounding grids of Alsynite sticky traps, and specimens were dissected to determine feeding histories and reproductive age. Distances and directions of 3,889 marked specimens indicated males and females dispersed equally and in all directions. Midguts of males and females were equally likely to contain blood-meal remnants. Percentage with blood remnants ...


Discrete Nonparametric Algorithms For Outlier Detection With Genomic Data, Debashis Ghosh 2010 Penn State University

Discrete Nonparametric Algorithms For Outlier Detection With Genomic Data, Debashis Ghosh

Debashis Ghosh

In high-throughput studies involving genetic data such as from gene expression mi- croarrays, dierential expression analysis between two or more experimental conditions has been a very common analytical task. Much of the resulting literature on multiple comparisons has paid relatively little attention to the choice of test statistic. In this article, we focus on the issue of choice of test statistic based on a special pattern of dierential expression. The approach here is based on recasting multiple comparisons procedures for assessing outlying expression values. A major complication is that the resulting p-values are discrete; some theoretical properties of sequential testing ...


Detecting Outlier Genes From High-Dimensional Data: A Fuzzy Approach, Debashis Ghosh 2010 Penn State University

Detecting Outlier Genes From High-Dimensional Data: A Fuzzy Approach, Debashis Ghosh

Debashis Ghosh

A recent nding in cancer research has been the characterization of previously undis- covered chromosomal abnormalities in several types of solid tumors. This was found based on analyses of high-throughput data from gene expression microarrays and motivated the development of so-called `outlier' tests for dierential expression. One statistical issue was the potential discreteness of the test statistics. Using ideas from fuzzy set theory, we develop fuzzy outlier detection algorithms that have links to ideas in multiple comparisons. Two- and K-sample extensions are considered. The methodology is illustrated by application to two microarray studies.


Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy M. Taylor, Michael R. Elliott 2010 Penn State University

Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy M. Taylor, Michael R. Elliott

Debashis Ghosh

There has been substantive interest in the assessment of surrogate endpoints in medical research. These are measures which could potentially replace \true" endpoints in clinical trials and lead to studies that require less follow-up. Recent research in the area has focused on assessments using causal inference frameworks. Beginning with a simple model for associating the surrogate and true endpoints in the population, we approach the problem as one of endogenous covariates. An instrumental variables estimator and general two-stage algorithm is proposed. Existing surrogacy frameworks are then evaluated in the context of the model. A numerical example is used to illustrate ...


Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy M. Taylor, Daniel J. Sargent 2010 Penn State University

Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy M. Taylor, Daniel J. Sargent

Debashis Ghosh

There has been great recent interest in the medical and statistical literature in the assessment and validation of surrogate endpoints as proxies for clinical endpoints in medical studies. More recently, authors have focused on using meta-analytical methods for quanti cation of surrogacy. In this article, we extend existing procedures for analysis based on the accelerated failure time model to this setting. An advantage of this approach relative to proportional hazards model is that it allows for analysis in the semi-competing risks setting, where we constrain the surrogate endpoint to occur before the true endpoint. A novel principal components procedure is ...


Spline-Based Models For Predictiveness Curves, Debashis Ghosh, Michael Sabel 2010 Penn State University

Spline-Based Models For Predictiveness Curves, Debashis Ghosh, Michael Sabel

Debashis Ghosh

A biomarker is dened to be a biological characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. The use of biomarkers in cancer has been advocated for a variety of purposes, which include use as surrogate endpoints, early detection of disease, proxies for environmental exposure and risk prediction. We deal with the latter issue in this paper. Several authors have proposed use of the predictiveness curve for assessing the capacity of a biomarker for risk prediction. For most situations, it is reasonable to assume monotonicity of ...


Combining Multiple Models With Survival Data: The Phase Algorithm, Debashis Ghosh, Zheng Yuan 2010 Penn State University

Combining Multiple Models With Survival Data: The Phase Algorithm, Debashis Ghosh, Zheng Yuan

Debashis Ghosh

In many scientic studies, one common goal is to develop good prediction rules based on a set of available measurements. This paper proposes a model averaging methodology using proportional hazards regression models to construct new estimators of predicted survival probabilities. A screening step based on an adaptive searching algorithm is used to handle large numbers of covariates. The nite-sample properties of the proposed methodology is assessed using simulation studies. Application of the method to a cancer biomarker study is also given.


Full Issue: Volume 4, Number 1, 2010 Touro College and University System

Full Issue: Volume 4, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


Data Sharing, Latency Variables And The Science Commons, Jorge L. Contreras 2010 Washington University in St Louis

Data Sharing, Latency Variables And The Science Commons, Jorge L. Contreras

Jorge L Contreras

Over the past decade, the rapidly decreasing cost of computer storage and the increasing prevalence of high-speed Internet connections have fundamentally altered the way in which scientific research is conducted. Led by scientists in disciplines such as genomics, the rapid sharing of data sets and cross-institutional collaboration promise to increase scientific efficiency and output dramatically. As a result, an increasing number of public “commons” of scientific data are being created: aggregations intended to be used and accessed by researchers worldwide. Yet, the sharing of scientific data presents legal, ethical and practical challenges that must be overcome before such science commons ...


Manipulating The Extent Of Delayed Onset Muscle Soreness, Ankita Dubey 2010 Ithaca College

Manipulating The Extent Of Delayed Onset Muscle Soreness, Ankita Dubey

Ithaca College Theses

Purpose: The purpose of study was to determine if three discrete levels of soreness can be identified using various magnitudes of eccentric triceps exercise in non-resistance trained, college-aged students. Methods: Male (n=12) and female (n=12) subjects were recruited and randomly assigned to a 20-, 40-, or 60-repetition group (n=8). Subjects performed maximal eccentric triceps contraction at 90''s-1 on a Cybex isokinetic dynamometer. Measurement of peak torque (PT), arm circumference (2, 6, and 9 cm), relaxed arm angle (RANG), elbow range of motion (ROM), descriptor differential scale (DDS) (sensation and unpleasantness), and creatine kinase (CK) were done ...


Us Per Capita Dairy Consumption 1950-2008, The Humane Society of the United States 2010 Animal Studies Repository

Us Per Capita Dairy Consumption 1950-2008, The Humane Society Of The United States

FARM ANIMAL DATA

No abstract provided.


Us Per Capita Egg Consumption 1950 - 2008, The Humane Society of the United States 2010 Animal Studies Repository

Us Per Capita Egg Consumption 1950 - 2008, The Humane Society Of The United States

FARM ANIMAL DATA

No abstract provided.


Male Territoriality In A Social Sciurid, Cynomys Gunnisoni: What Do Patterns Of Paternity Tell Us?, J. L. Verdolin, C. N. Slobodchikoff 2010 Stony Brook University

Male Territoriality In A Social Sciurid, Cynomys Gunnisoni: What Do Patterns Of Paternity Tell Us?, J. L. Verdolin, C. N. Slobodchikoff

VETERINARY SCIENCE AND MEDICINE

In many social sciurids, male territoriality confers significant mating advantages. We evaluated resident male paternity in Gunnison’s prairie dogs (Cynomys gunnisoni), a colonial ground-dwelling sciurid, where males and females cooperatively defend territories. Contrary to findings reported for other social sciurids, our results show that territorial resident males do not gain significant reproductive advantages. Resident males sired the majority of offspring from their respective territories only 10.5% of the time. A single non-resident male sired equal or greater number of offspring than any single resident male 71.2% of the time. While adult males were more likely to sire ...


About Turkeys, The Humane Society of the United States 2010 Animal Studies Repository

About Turkeys, The Humane Society Of The United States

AGRIBUSINESS

John James Audubon, a well-known bird expert and nature enthusiast, described wild turkeys as birds of great beauty. The history and origin of wild turkeys is uncertain, yet many share Audubon’s sentiment that the wild turkey is “one of the most interesting of the birds indigenous to the United States of America.” Today, wild turkeys can be found throughout the nation. Following the selection of the bald eagle as the American symbol, Benjamin Franklin remarked that the turkey was more “respectable”, and a “true original native”.


About Chickens, The Humane Society of the United States 2010 Animal Studies Repository

About Chickens, The Humane Society Of The United States

AGRIBUSINESS

The chicken is the world’s most numerous domesticated bird, with over 52 billion farmed worldwide in 2008, rivaling the dog as the most ubiquitous domestic animal globally. These birds have fascinated scholars and researchers since the dawn of Western civilization, and recent studies are beginning to reveal the depths of their complexity and cognitive ability. According to Andrew F. Fraser, professor of veterinary surgery at Memorial University of Newfoundland, and Donald M. Broom, professor of animal welfare at University of Cambridge: “Those who have studied the behaviour of the domestic fowl in detail…, especially those who have looked at ...


Laboratory Rodent Welfare: Thinking Outside The Cage, Jonathan P. Balcombe 2010 Independent Scientist and Author

Laboratory Rodent Welfare: Thinking Outside The Cage, Jonathan P. Balcombe

LABORATORY EXPERIMENTS

This commentary presents the case against housing rats and mice in laboratory cages; the commentary bases its case on their sentience, natural history, and the varied detriments of laboratory conditions. The commentary gives 5 arguments to support this position: (a) rats and mice have a high degree of sentience and can suffer, (b) laboratory environments cause suffering, (c) rats and mice in the wild have discrete behavioral needs, (d) rats and mice bred for many generations in the laboratory retain these needs, and (e) these needs are not met in laboratory cages.


Toward Genuine Rodent Welfare: Response To Reviewer Comments, Jonathan P. Balcombe 2010 Independent Scientist and Author

Toward Genuine Rodent Welfare: Response To Reviewer Comments, Jonathan P. Balcombe

LABORATORY EXPERIMENTS

I’m grateful to the editors for soliciting critiques of my commentary and for the opportunity to respond. Because one of the respondents (Patterson-Kane, 2010/this issue) does not take issue with the main points of my article, whereas the other (Blanchard, 2010/this issue) does, I focus my remarks here mostly on Blanchard’s critique.


Vigilance And Antipredator Responses Of Caribbean Reef Squid, Jennifer A. Mather 2010 University of Lethbridge

Vigilance And Antipredator Responses Of Caribbean Reef Squid, Jennifer A. Mather

SENTIENCE

Antipredator responses, especially those of open-ocean squid, have been seldom studied in the natural environment. Sepioteuthis sepioidea, observed by snorkellers near the shore in early morning/late afternoon, produced an average of eight moves of over 1m per hour, apparently mostly antipredator behaviours. Close approaches by herbivorous parrotfish elicited no response in 74% of encounters; otherwise, squid produced agonistic zebra stripes or startle-mantle-dots skin patterns. Predatory bar jack fish caused flight but not zebra displays, and squid usually paled and fled quickly (66%) from snapper. The speed of approach was the best predictor for flight and display responses to snapper ...


Squid Dances: An Ethogram Of Postures And Actions Of Sepioteuthis Sepioidea Squid With A Muscular Hydrostatic System, Jennifer A. Mather, Ulrike Griebel, Ruth A. Byrne 2010 University of Lethbridge

Squid Dances: An Ethogram Of Postures And Actions Of Sepioteuthis Sepioidea Squid With A Muscular Hydrostatic System, Jennifer A. Mather, Ulrike Griebel, Ruth A. Byrne

SENTIENCE

A taxonomy of the movement possibilities for any species, within the constraints of its neural and skeletal systems, should be one of the foundations of the study of its behaviour. Caribbean reef squid, Sepioteuthis sepioidea, appear to have many degrees of freedom in their movement as they live in a three-dimensional habitat and have no fixed skeleton but rather a muscular hydrostatic one. Within this apparent lack of constraints, there are regularities and patterns of common occurrences that allow this article to describe an ethogram of the movements, postures and positions of squid. Squid have a combination of bent, spread ...


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