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A Fresh Cow Health Monitoring System, Amanda E. Sterrett, Donna M. Amaral-Phillips, Jeffrey M. Bewley, Michelle Arnold Mar 2014

A Fresh Cow Health Monitoring System, Amanda E. Sterrett, Donna M. Amaral-Phillips, Jeffrey M. Bewley, Michelle Arnold

Agriculture and Natural Resources Publications

Calving causes cows to endure many physiological changes that require good nutrition, time, and adequate rest for recovery. Upon calving, cows are introduced into the lactating herd, where they consume high amounts of a new ration and have to adapt to a new feeding and milking routine. Lactation requires more support from the diet than pregnancy and weight maintenance, particularly in fresh cows calving in with a negative energy balance. Additionally, the social hierarchy within the herd is re-established every time a new cow enters the group, which can cause stress, especially for timid and weak cows. For these reasons, …


Selective Anion Sensing By Chiral Macrocyclic Receptors With Multiple Hydrogen-Bonding Sites, Tadashi Ema, Keiichi Okuda, Sagiri Watanabe, Takayuki Yamasaki, Tsuyoshi Minami, Nina A. Esipenko, Pavel Anzenbacher Jr. Mar 2014

Selective Anion Sensing By Chiral Macrocyclic Receptors With Multiple Hydrogen-Bonding Sites, Tadashi Ema, Keiichi Okuda, Sagiri Watanabe, Takayuki Yamasaki, Tsuyoshi Minami, Nina A. Esipenko, Pavel Anzenbacher Jr.

Chemistry Faculty Publications

Chiral macrocycles featuring sulfonamide and/or amide groups as anion-binding sites were synthesized. X-ray crystal structures and DFT calculations have shown that they adopt different conformations that may lead to unique binding behavior. Indeed, various anions could be sensed by their colorimetric and/or fluorescence signal output. The chiral macrocycles showed chiral recognition for chiral anions. Furthermore, a multisensor array with two or four chiral receptors discriminated seven phosphate anions (AMP, ADP, ATP, CMP, GMP, Pi, and PPi) with 100% classification accuracy.


Comparative Analysis Of Two Successive Vintages Of Cabernet Sauvignon Must And Pre-Barrel Wine From Two Distinct Soil Types, Jon Garret Page Mar 2014

Comparative Analysis Of Two Successive Vintages Of Cabernet Sauvignon Must And Pre-Barrel Wine From Two Distinct Soil Types, Jon Garret Page

Master's Theses

The objective of this study was to determine if there were significant statistical differences in the response variables of Cabernet Sauvignon must and pre-barreled wine analyzed from two vintages from two distinct soil types.

Research was conducted at California Polytechnic University, San Luis Obispo to examine the quantitative chemical analysis of 22 different response variables of Cabernet Sauvignon grapes. The same 22 variables were analyzed in must and pre-barreled wine samples harvested from both Calodo Clay Loam soil and Zaca Clay soil. The analyses were done at both California Polytechnic University, San Luis Obispo and Vinquiry Inc. Labs. The results …


Mechanisms Of Soil Carbon Accrual And Storage In Bioenergy Cropping Systems, Lisa K. Tiemann, A. Stuart Grandy Mar 2014

Mechanisms Of Soil Carbon Accrual And Storage In Bioenergy Cropping Systems, Lisa K. Tiemann, A. Stuart Grandy

Faculty Publications

Annual row cropping systems converted to perennial bioenergy crops tend to accrue soil C, likely a function of increased root production and decreased frequency of tillage; however, very little is known about the mechanisms governing the accrual and stability of this additional soil C. To address this uncertainty, we assessed the formation and stability of aggregates and soil organic C (SOC) pools under switchgrass, giant miscanthus, a native perennial grass mix and continuous corn treatments in Michigan and Wisconsin soils differing in both texture and mineralogy. We isolated different aggregate size fractions, >2 mm, 0.5–2 mm, and <0.5 mm, using a procedure intended to minimize alterations to aggregate biological and chemical properties. We determined SOC, permanganate oxidizable C (POXC), and microbial activities (i.e. enzyme activities and soil respiration rates) associated with these aggregates. Soil type strongly influenced the trajectory of aggregate formation and stabilization with differences between sites in mean aggregate size, stability, SOC and microbial activity under perennial vs. corn cropping systems. At the Michigan site, soil microbial activities were highest in the >2 mm aggregates, …


Hurricane Preparedness: Community Vulnerability And Medically Fragile Populations, Joshua G. Behr, Rafael Diaz Feb 2014

Hurricane Preparedness: Community Vulnerability And Medically Fragile Populations, Joshua G. Behr, Rafael Diaz

VMASC Publications

No abstract provided.


Bioelectrical Impedance Analysis As A Laboratory Activity: At The Interface Of Physics And The Body, Elliot Mylott, Ellynne Marie Kutschera, Ralf Widenhorn Feb 2014

Bioelectrical Impedance Analysis As A Laboratory Activity: At The Interface Of Physics And The Body, Elliot Mylott, Ellynne Marie Kutschera, Ralf Widenhorn

Physics Faculty Publications and Presentations

We present a novel laboratory activity on RC circuits aimed at introductory physics students in life-science majors. The activity teaches principles of RC circuits by connecting ac-circuit concepts to bioelectrical impedance analysis (BIA) using a custom-designed educational BIA device. The activity shows how a BIA device works and how current, voltage, and impedance measurements relate to bioelectrical characteristics of the human body. From this, useful observations can be made including body water, fat-free mass, and body fat percentage. The laboratory is engaging to pre-health and life-science students, as well as engineering students who are given the opportunity to observe electrical …


Detection And Assay Of Riboflavin (Vitamin B2) Utilizing Uv/Vis Spectrophotometer And Citric Acid Buffer, Ronald Bartzatt, Michelle Lee Follis Jan 2014

Detection And Assay Of Riboflavin (Vitamin B2) Utilizing Uv/Vis Spectrophotometer And Citric Acid Buffer, Ronald Bartzatt, Michelle Lee Follis

Chemistry Faculty Publications

Aims: Riboflavin is a B vitamin that is required for a wide variety of cellular processes. The absorbance spectrum of riboflavin was determined at different pH utilizing several buffers. The buffer at pH demonstrating table absorbance peaks with high numerical values of molar absorptivity is followed by accurate and sensitive assay of riboflavin by spectrophotometer. Study Design: The absorbance spectrum of riboflavin is determined in an aqueous buffer at various pH values. After identifying the absorbance peaks providing maximal molar absorptivity the assay of riboflavin in the identical buffer was undertaken. Place and Duration of Study: Department of Chemistry, Durham …


Relationship Between Altitude And Lithium In Groundwater In The United States Of America: Results Of A 1992–2003 Study, Rebekah S. Huber, Namkug Kim, Carl E. Renshaw, Perry F. Renshaw, Douglas Kondo Jan 2014

Relationship Between Altitude And Lithium In Groundwater In The United States Of America: Results Of A 1992–2003 Study, Rebekah S. Huber, Namkug Kim, Carl E. Renshaw, Perry F. Renshaw, Douglas Kondo

Dartmouth Scholarship

Therapeutic dosages of lithium are known to reduce suicide rates, which has led to investigations of confounding environmental risk factors for suicide such as lithium in groundwater. It has been speculated that this might play a role in the potential relationship between suicide and altitude. A recent study in Austria involving geospatial analysis of lithium in groundwater and suicide found lower levels of lithium at higher altitudes. Since there is no reason to suspect this correlation is universal given variation in geology, the current study set out to investigate the relationship between altitude and lithium in groundwater in the United …


Skin Lesion Extraction And Its Application, Yanliang Gu Jan 2014

Skin Lesion Extraction And Its Application, Yanliang Gu

Dissertations, Master's Theses and Master's Reports - Open

In this thesis, I study skin lesion detection and its applications to skin cancer diagnosis. A skin lesion detection algorithm is proposed. The proposed algorithm is based color information and threshold. For the proposed algorithm, several color spaces are studied and the detection results are compared. Experimental results show that YUV color space can achieve the best performance. Besides, I develop a distance histogram based threshold selection method and the method is proven to be better than other adaptive threshold selection methods for color detection. Besides the detection algorithms, I also investigate GPU speed-up techniques for skin lesion extraction and …


Local Awareness Of And Attitudes Toward Pygmy Hippopotamus Conservation In The Moa River Island Complex, Sierra Leone., April L. Conway, Sonia M. Hernandez, John P. Carroll, Gary T. Green, Lincoln Larson Jan 2014

Local Awareness Of And Attitudes Toward Pygmy Hippopotamus Conservation In The Moa River Island Complex, Sierra Leone., April L. Conway, Sonia M. Hernandez, John P. Carroll, Gary T. Green, Lincoln Larson

School of Natural Resources: Faculty Publications

Abstract The pygmy hippopotamus Choeropsis liberiensis is an Endangered species found only in the Upper Guinea rainforests of West Africa. Using a two-phase approach, with initial semi-structured interviews followed by more extensive questionnaires, we examined local residents’ awareness of and attitudes towards the pygmy hippopotamus along the Moa River near Tiwai Island Wildlife Sanctuary in Sierra Leone. The interviews and questionnaires addressed human–hippopotamus interactions, local knowledge and awareness of pygmy hippopotamus ecology and behaviour, and public attitudes towards hippopotamus conservation. Overall, 22% of questionnaire respondents acknowledged benefits related to hippopotamus conservation; factors affecting the perception of benefits included age, livestock …


You Are Not Always What We Think You Eat: Selective Assimilation Across Multiple Whole-Stream Isotopic Tracer Studies, W. K. Dodds, S. M. Collins, S. K. Hamilton, J. L. Tank, S. Johnson, J. R. Webster, K. S. Simon, M. R. Whiles, H. M. Rantala, W. H. Mcdowell, S. D. Peterson, T. Riis, C. L. Crenshaw, S. A. Thomas, P. B. Kristensen, B. M. Cheever, A. S. Flecker, N. A. Griffiths, T. Crowl, E. J. Rosi-Marshall, R. El-Sabaawi, E. Marti Jan 2014

You Are Not Always What We Think You Eat: Selective Assimilation Across Multiple Whole-Stream Isotopic Tracer Studies, W. K. Dodds, S. M. Collins, S. K. Hamilton, J. L. Tank, S. Johnson, J. R. Webster, K. S. Simon, M. R. Whiles, H. M. Rantala, W. H. Mcdowell, S. D. Peterson, T. Riis, C. L. Crenshaw, S. A. Thomas, P. B. Kristensen, B. M. Cheever, A. S. Flecker, N. A. Griffiths, T. Crowl, E. J. Rosi-Marshall, R. El-Sabaawi, E. Marti

School of Natural Resources: Faculty Publications

Analyses of 21 15N stable isotope tracer experiments, designed to examine food web dynamics in streams around the world, indicated that the isotopic composition of food resources assimilated by primary consumers (mostly invertebrates) poorly reflected the presumed food sources. Modeling indicated that consumers assimilated only 33–50% of the N available in sampled food sources such as decomposing leaves, epilithon, and fine particulate detritus over feeding periods of weeks or more. Thus, common methods of sampling food sources consumed by animals in streams do not sufficiently reflect the pool of N they assimilate. Isotope tracer studies, combined with modeling and …


2014 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Lauren R. Dinan Jan 2014

2014 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Lauren R. Dinan

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2013–2014). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The lower Platte River and its major tributaries provide important nesting and migratory stopover habitat for two bird species of special conservation concern: the state and federally endangered Interior Least Tern (Sternula antillarum athalassos) and threatened Piping Plover (Charadrius melodus). The Tern and Plover Conservation Partnership (TPCP), based at the University of …


Water Metrics, Lisa-Maria Rebelo, Jean-Marc Faurès, Poolad Karimi, Wim Bastiaanssen, Meredith Giordano, Vladimir Smakhtin, Peter G. Mccornick Jan 2014

Water Metrics, Lisa-Maria Rebelo, Jean-Marc Faurès, Poolad Karimi, Wim Bastiaanssen, Meredith Giordano, Vladimir Smakhtin, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Society has a universal need for water that crosses all sectors of activity. We need to be able to measure progress towards sustainable water for all by working towards targets that consider the different dimensions of water resources and use, including water quantity and quality. A suite of indicators that reflect water use by different sectors is needed to measure progress towards the forthcoming SDGs’ [sustainable development goals] water-related targets. Such indicators will need to rely on national data, must consider the variation in data availability, and can be complemented with new cost-effective ways for data collection.

Remote sensing measurements, …


Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Peter G. Mccornick Jan 2014

Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 years old) who are lifelong residents of 33 rural communities in which groundwater concentrations of F− cover a wide range. A subset of 156 children was selected for urinary F− measurements. Our results showed that the mean F− concentrations in groundwater were 8.5 ± 4.1 mg/L (range: 1.1–18 mg/L), while those in urine …


The Effect Of Non-Fluoride Factors On Risk Of Dental Fluorosis: Evidence From Rural Populations Of The Main Ethiopian Rift, Julia Kravchenko, Tewodros Rango, Igor Akushevich, Behailu Atlaw, Peter G. Mccornick, R. Brittany Merola, Christopher Paul, Erika Weinthal, Courtney Harrison, Avner Vengosh, Marc Jeuland Jan 2014

The Effect Of Non-Fluoride Factors On Risk Of Dental Fluorosis: Evidence From Rural Populations Of The Main Ethiopian Rift, Julia Kravchenko, Tewodros Rango, Igor Akushevich, Behailu Atlaw, Peter G. Mccornick, R. Brittany Merola, Christopher Paul, Erika Weinthal, Courtney Harrison, Avner Vengosh, Marc Jeuland

Daugherty Water for Food Global Institute: Faculty Publications

Elevated level of fluoride (F−) in drinking water is a well-recognized risk factor of dental fluorosis (DF). While considering optimization of region-specific standards for F−, it is reasonable, however, to consider how local diet, water sourcing practices, and non-F− elements in water may be related to health outcomes. In this study, we hypothesized that non-F− elements in groundwater and lifestyle and demographic characteristics may be independent predictors or modifiers of the effects of F− on teeth. Dental examinations were conducted among 1094 inhabitants from 399 randomly selected households of 20 rural communities of …


Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Paul Mccornick Jan 2014

Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Paul Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 years old) who are lifelong residents of 33 rural communities in which …


05. Chemistry, University Of Central Oklahoma Jan 2014

05. Chemistry, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


Shape Evolution And Sexual Dimorphism In The Mandible Of The Dire Wolf, Canis Dirus, At Rancho La Brea, Alexandria L. Brannick Jan 2014

Shape Evolution And Sexual Dimorphism In The Mandible Of The Dire Wolf, Canis Dirus, At Rancho La Brea, Alexandria L. Brannick

Theses, Dissertations and Capstones

The Rancho La Brea tar pits are a classic fossil lagerstätten, famous for the deposition of episodic accumulations of large numbers of fossils over short intervals in the late Pleistocene. I analyzed 157 Canis dirus (dire wolf) hemi-mandibles from Rancho La Brea through a 2D landmark-based morphometric analysis to test for size and shape changes through time. I scored 16 landmarks on each mandible gathered from four pits of different ages: 61/67 (~13-14 thousand years ago [ka]), 13 (~17-18 ka), 2051 (~26 ka), and 91 (~28 ka). Analyses indicate size does change through time, and shares a broad correlation with …


Energy Expenditure In The Backcountry, Mandy Pojha, Cara Ocobock, John Gookin Jan 2014

Energy Expenditure In The Backcountry, Mandy Pojha, Cara Ocobock, John Gookin

Research in Outdoor Education

The study of energy economics, known as energetics, has played a key role in shaping human ecology, evolution, and performance (Leonard & Ulijaszek, 2002). Research on energetics gives insight into how humans interact with their environment and how differences in body shape and size can impact that interaction. This understanding is particularly insightful for humans living in the backcountry for extended periods of time. Selecting food types and amounts to meet high-energy demands in the backcountry setting is a challenge, because energy demand models have primarily been based on lab studies that, in hindsight, appear to routinely underestimate energy demands …


03. Biology, University Of Central Oklahoma Jan 2014

03. Biology, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


02. Animal Science, University Of Central Oklahoma Jan 2014

02. Animal Science, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


11. Genetics, University Of Central Oklahoma Jan 2014

11. Genetics, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


The Role Of Ugandan Women In Rural Agriculture And Food Security, Karen Ann Mckenna Jan 2014

The Role Of Ugandan Women In Rural Agriculture And Food Security, Karen Ann Mckenna

Electronic Theses and Dissertations

Women engaged in small-scale rural agriculture in Iganga, Uganda for the purpose of household food security and/or income generation face a number of challenges to creating sustainable livelihoods. This analysis is presented in the form of a case study based on research conducted over the period of one year in Uganda between September 2012 and September 2013. Three conceptual orientations are used to guide the research, including sustainable livelihoods, gender and agricultural development, and food security. Pertinent economic, political, and social contexts are identified for each of these orientations. The author then identifies key challenges that women in Iganga face …


Ua12/13 2014 Sustainability Report [Western Kentucky University], Wku Office Of Sustainability, Christian Ryan-Downing Jan 2014

Ua12/13 2014 Sustainability Report [Western Kentucky University], Wku Office Of Sustainability, Christian Ryan-Downing

Sustainability Publications and Resources

No abstract provided.


The View From Ventress - 2014, University Of Mississippi. College Of Liberal Arts Jan 2014

The View From Ventress - 2014, University Of Mississippi. College Of Liberal Arts

Liberal Arts Newsletters

Special Section: The Rise of Health Professions. Over the past decade, the health-care sector added jobs month after month, even when jobs were disappearing elsewhere in the economy. The field is projected to add many more in the coming decade, so it makes sense that the number of students majoring in health-related fields rose sharply. Roughly one in 10 college graduates now gets a health-related degree.


Magnesium As A Regulator Of Hepatic Nadph In The Hepatocyte :;Prospective Roles Of Magnesium In Diabetes And Obesity Onset, Chesinta B. Voma Jan 2014

Magnesium As A Regulator Of Hepatic Nadph In The Hepatocyte :;Prospective Roles Of Magnesium In Diabetes And Obesity Onset, Chesinta B. Voma

ETD Archive

No abstract provided.


The Inky Story Of The Dinky Oak Gall, Ken Sulak Jan 2014

The Inky Story Of The Dinky Oak Gall, Ken Sulak

United States Geological Survey: Staff Publications

Maybe you have noticed these little spheres before – but did not give them much thought. Or maybe, you puzzled: What are these wooden pearls? How did they get there? Well, a tiny wasp, called the pea galler wasp or gallfly, Belonocnema treatae, is the culprit. The diminutive female gallfly (one of nearly a thousand species in the gall wasp family Cynipidae), about the size of a fire ant, lays eggs on a freshly budded live oak leaf in spring. When the larva hatches, it produces a chemical that induces the oak to enclose it in a protective and …


Fire Effects On Seedling Establishment Success Across Treeline: Implications For Future Tree Migration And Flammability In A Changing Climate, F. S. Chapin Iii, Teresa N. Hollingsworth, Rebecca E. Hewitt Jan 2014

Fire Effects On Seedling Establishment Success Across Treeline: Implications For Future Tree Migration And Flammability In A Changing Climate, F. S. Chapin Iii, Teresa N. Hollingsworth, Rebecca E. Hewitt

Joint Fire Science Program Research Project Reports

Understanding the complex mechanisms controlling treeline advance or retreat in the arctic and subarctic has important implications for projecting ecosystem response to changes in climate. Changes in landcover due to a treeline biome shift would alter climate feedbacks (carbon storage and energy exchange), ecosystem services such as wildlife and berry habitat, and landscape flammability. Wildfire frequency and extent has increased in the last half-century in the boreal forest and tundra in response to warmer weather and lower precipitation. Invasion of tundra by trees may be facilitated by wildfire disturbance, which exposes new seedbeds, increases nutrient availability immediately post-fire, and creates …


Short And Long-Term Lifestyle Coaching Approaches Used To Address Diverse Participant Barriers To Weight Loss And Physical Activity Adherence, Elizabeth M. Venditti, Judith Wylie-Rosett, Linda M. Delahanty, Lisa L. Mele, Mary A. Hoskin, Sharon Edelstein Jan 2014

Short And Long-Term Lifestyle Coaching Approaches Used To Address Diverse Participant Barriers To Weight Loss And Physical Activity Adherence, Elizabeth M. Venditti, Judith Wylie-Rosett, Linda M. Delahanty, Lisa L. Mele, Mary A. Hoskin, Sharon Edelstein

GW Biostatistics Center

Background

Individual barriers to weight loss and physical activity goals in the Diabetes Prevention Program, a randomized trial with 3.2 years average treatment duration, have not been previously reported. Evaluating barriers and the lifestyle coaching approaches used to improve adherence in a large, diverse participant cohort can inform dissemination efforts.

Methods

Lifestyle coaches documented barriers and approaches after each session (mean session attendance = 50.3 +/- 21.8). Subjects were 1076 intensive lifestyle participants (mean age = 50.6 years; mean BMI = 33.9 kg/m2; 68% female, 48% non-Caucasian). Barriers and approaches used to improve adherence were ranked by the percentage of …


Cardiometabolic Risk Assessments By Body Mass Index Z-Score Or Waist-To-Height Ratio In A Multiethnic Sample Of Sixth-Graders, Henry S. Kahn, Laure El Ghormli, Russell Jago, Gary D. Foster, Robert G. Mcmurray, John B. Buse, Diane D. Stadler, Roberto P. Trevino, Tom Baranowski, Healthy Study Group Jan 2014

Cardiometabolic Risk Assessments By Body Mass Index Z-Score Or Waist-To-Height Ratio In A Multiethnic Sample Of Sixth-Graders, Henry S. Kahn, Laure El Ghormli, Russell Jago, Gary D. Foster, Robert G. Mcmurray, John B. Buse, Diane D. Stadler, Roberto P. Trevino, Tom Baranowski, Healthy Study Group

GW Biostatistics Center

Convention defines pediatric adiposity by the body mass index -score (BMIz) referenced to normative growth charts. Waist-to-height ratio (WHtR) does not depend on sex-and-age references. In the HEALTHY Study enrollment sample, we compared BMIz with WHtR for ability to identify adverse cardiometabolic risk. Among 5,482 sixth-grade students from 42 middle schools, we estimated explanatory variations (R2) and standardized beta coefficients of BMIz or WHtR for cardiometabolic risk factors: insulin resistance (HOMA-IR), lipids, blood pressures, and glucose. For each risk outcome variable, we prepared adjusted regression models for four subpopulations stratified by sex and high versus lower fatness. …