Digital Commons Network^™

Using Built Environment Characteristics To Predict Walking For Exercise, Gina S. Lovasi, Anne V. Moudon, Amber L. Pearson, Philip M. Hurvitz, Eric B. Larson, David S. Siscovick, Ethan M. Berke

Dartmouth Scholarship

Environments conducive to walking may help people avoid sedentary lifestyles and associated diseases. Recent studies developed walkability models combining several built environment characteristics to optimally predict walking. Developing and testing such models with the same data could lead to overestimating one's ability to predict walking in an independent sample of the population. More accurate estimates of model fit can be obtained by splitting a single study population into training and validation sets (holdout approach) or through developing and evaluating models in different populations. We used these two approaches to test whether built environment characteristics near the home predict walking for …

Surgical Versus Nonsurgical Therapy For Lumbar Spinal Stenosis., James N Weinstein, Tor D Tosteson, Jon D Lurie, Anna N A Tosteson, Emily Blood, Brett Hanscom, Harry Herkowitz, Frank Cammisa, Todd Albert, Scott D Boden, Alan Hilibrand, Harley Goldberg, Sigurd Berven, Howard An

Rothman Institute Papers

BACKGROUND: Surgery for spinal stenosis is widely performed, but its effectiveness as compared with nonsurgical treatment has not been shown in controlled trials.

METHODS: Surgical candidates with a history of at least 12 weeks of symptoms and spinal stenosis without spondylolisthesis (as confirmed on imaging) were enrolled in either a randomized cohort or an observational cohort at 13 U.S. spine clinics. Treatment was decompressive surgery or usual nonsurgical care. The primary outcomes were measures of bodily pain and physical function on the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36) and the modified Oswestry Disability Index at 6 weeks, …

Surgical Versus Nonsurgical Therapy For Lumbar Spinal Stenosis., James N Weinstein, Tor D Tosteson, Jon D Lurie, Anna N A Tosteson, Emily Blood, Brett Hanscom, Harry Herkowitz, Frank Cammisa, Todd J Albert, Scott D Boden, Alan Hilibrand, Harley Goldberg, Sigurd Berven, Howard An

Rothman Institute Papers

BACKGROUND: Surgery for spinal stenosis is widely performed, but its effectiveness as compared with nonsurgical treatment has not been shown in controlled trials.

METHODS: Surgical candidates with a history of at least 12 weeks of symptoms and spinal stenosis without spondylolisthesis (as confirmed on imaging) were enrolled in either a randomized cohort or an observational cohort at 13 U.S. spine clinics. Treatment was decompressive surgery or usual nonsurgical care. The primary outcomes were measures of bodily pain and physical function on the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36) and the modified Oswestry Disability Index at 6 weeks, …

Sputum Microscopy For The Diagnosis Of Hiv-Associated Pulmonary Tuberculosis In Tanzania, Mecky Matee, Lillian Mtei, Tarja Lounasvaara, Wendy Wieland-Alter, Richard Waddell, Johnson Lyimo, Muhammed Bakari, Kisali Pallangyo, C Fordham Von Reyn

Dartmouth Scholarship

Background:

In many resource poor settings only sputum microscopy is employed for the diagnosis of HIV-associated pulmonary tuberculosis; sputum culture may not be available.

Methods:

We determined the diagnostic accuracy of sputum microscopy for active case finding of HIV-associated pulmonary tuberculosis using TB culture as the reference standard.

Results:

2216 potential subjects screened for a TB vaccine trial submitted 9454 expectorated sputum specimens: 212 (2.2%) were sputum culture positive for Mycobacterium tuberculosis (MTB), 31 (0.3%) for non-tuberculous mycobacteria, and 79 (0.8%) were contaminated. The overall sensitivity of sputum microscopy was 61.8% (131/212) and specificity 99.7% (9108/9132). Sputum microscopy sensitivity varied …

Celecoxib Concentration Predicts Decrease In Prostaglandin E2 Concentrations In Nipple Aspirate Fluid From High Risk Women, Edward R. Sauter, Wenyi Qin, John E. Hewett, Rachel L. Ruhlen, John T. Flynn, George Rottinghaus, Yin-Chieh Chen

Department of Molecular Physiology and Biophysics Faculty Papers

BACKGROUND: Epidemiologic studies suggest that long term low dose celecoxib use significantly lowers breast cancer risk. We previously demonstrated that 400 mg celecoxib taken twice daily for 2 weeks lowered circulating plasma and breast nipple aspirate fluid (NAF) prostaglandin (PG)E2 concentrations in post- but not premenopausal high risk women. We hypothesized that circulating concentrations of celecoxib influenced PGE2 response, and that plasma levels of the drug are influenced by menopausal status. To address these hypotheses, the aims of the study were to determine: 1) if circulating plasma concentrations of celecoxib correlated with the change in plasma or NAF PGE2 concentrations …

Bradykinin Type 2 Receptor Be1 Genotype Influences Bradykinin-Dependent Vasodilation During Angiotensin-Converting Enzyme Inhibition, Gary Van Guilder, Mias Pretorius, James M Luther, J Brian Byrd, Kevin Hill, James V Gainer, Nancy J Brown

Health and Nutritional Sciences Faculty Publications

To test the hypothesis that the bradykinin receptor 2 (BDKRB2) BE1+9/-9 polymorphism affects vascular responses to bradykinin, we measured the effect of intra-arterial bradykinin on forearm blood flow and tissue-type plasminogen activator (t-PA) release in 89 normotensive, nonsmoking, white American subjects in whom degradation of bradykinin was blocked by enalaprilat. BE1 genotype frequencies were +9/+9:+9/-9:-9/-9=19:42:28. BE1 genotype was associated with systolic blood pressure (121.4+/-2.8, 113.8+/-1.8, and 110.6+/-1.8 mm Hg in +9/+9, +9/-9, and -9/-9 groups, respectively; P=0.007). In the absence of enalaprilat, bradykinin-stimulated forearm blood flow, forearm vascular resistance, and net t-PA release were similar among genotype groups. Enalaprilat increased …

Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan

Obstetrics & Gynaecology Publications

Preimplantation development directs the formation of an implantation- or attachment-competent embryo so that metabolic interactions with the uterus can occur, pregnancy can be initiated, and fetal development can be sustained. The preimplantation embryo exhibits a form of autonomous development fueled by products provided by the oocyte and also from activation of the embryo's genome. Despite this autonomy, the preimplantation embryo is highly influenced by factors in the external environment and in extreme situations, such as those presented by embryo culture or nuclear transfer, the ability of the embryo to adapt to the changing environmental conditions or chromatin to become reprogrammed …

Chronic Late-Gestation Hypoglycemia Upregulates Hepatic Pepck Associated With Increased Pgc1alpha Mrna And Phosphorylated Creb In Fetal Sheep., Paul J Rozance, Sean W Limesand, James S Barry, Laura D Brown, Stephanie R Thorn, Dan Loturco, Timothy Regnault, Jacob E Friedman, William W Hay

Paediatrics Publications

Hepatic glucose production is normally activated at birth but has been observed in response to experimental hypoglycemia in fetal sheep. The cellular basis for this process remains unknown. We determined the impact of 2 wk of fetal hypoglycemia during late gestation on enzymes responsible for hepatic gluconeogenesis, focusing on the insulin-signaling pathway, transcription factors, and coactivators that regulate gluconeogenesis. Hepatic phosphoenolpyruvate carboxykinase and glucose-6-phosphatase mRNA increased 12-fold and 7-fold, respectively, following chronic hypoglycemia with no change in hepatic glycogen. Chronic hypoglycemia decreased fetal plasma insulin with no change in glucagon but increased plasma cortisol 3.5-fold. Peroxisome proliferator-activated receptor-gamma coactivator-1alpha mRNA …

Current Application Of Thoracoscopy In Children., Kuojen Tsao, Shawn D. St Peter, Susan W. Sharp, Abhilash Nair, Walter S. Andrews, Ronald J. Sharp, Charles L. Snyder, Daniel J. Ostlie, G W. Holcomb Iii

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: The safety and efficacy of thoracoscopy for thoracic lesions and conditions in children is evolving. Our experience with thoracoscopy has expanded in recent years. Therefore, we reviewed our most recent 7-year experience to examine the current applications for thoracoscopy in children.

METHODS: A retrospective review of all patients undergoing a thoracoscopic operation at Children's Mercy Hospital (Kansas City, MO) between January 1, 2000, and June 18, 2007, was performed. Data points reviewed included patient demographics, type of operation, final diagnosis, complications, and recovery.

RESULTS: During the study period, 230 children underwent 231 thoracoscopic procedures. The mean age was 9.6 …

Focal White Matter Changes In Spasmodic Dysphonia: A Combined Diffusion Tensor Imaging And Neuropathological Study, Kristina Simonyan, Fernanda Tovar-Moll, John Ostuni, Mark Hallett, Victor F Kalasinsky, Michael R Lewin-Smith, Elisabeth J Rushing, Alexander O Vortmeyer, Christy L Ludlow

Faculty, Staff and Student Publications

Spasmodic dysphonia is a neurological disorder characterized by involuntary spasms in the laryngeal muscles during speech production. Although the clinical symptoms are well characterized, the pathophysiology of this voice disorder is unknown. We describe here, for the first time to our knowledge, disorder-specific brain abnormalities in these patients as determined by a combined approach of diffusion tensor imaging (DTI) and postmortem histopathology. We used DTI to identify brain changes and to target those brain regions for neuropathological examination. DTI showed right-sided decrease of fractional anisotropy in the genu of the internal capsule and bilateral increase of overall water diffusivity in …

Medulloblastomas Overexpress The P53-Inactivating Oncogene Wip1/Ppm1d, Robert C. Castellino, Massimiliano De Bortoli, Xiongbin Lu, Sung-Hwan Moon, Thuy-Ai Nguyen, Mark A. Shepard, Pulivarthi H. Rao, Lawrence A. Donehower, John Y H Kim

Faculty, Staff and Students Publications

Medulloblastoma is the most common malignant brain tumor of childhood. Despite numerous advances, clinical challenges range from recurrent and progressive disease to long-term toxicities in survivors. The lack of more effective, less toxic therapies results from our limited understanding of medulloblastoma growth. Although TP53 is the most commonly altered gene in cancers, it is rarely mutated in medulloblastoma. Accumulating evidence, however, indicates that TP53 pathways are disrupted in medulloblastoma. Wild-type p53-induced phosphatase 1 (WIP1 or PPM1D) encodes a negative regulator of p53. WIP1 amplification (17q22-q23) and its overexpression have been reported in diverse cancer types. We examined primary medulloblastoma specimens …

Dissociation Predicts Later Attention Problems In Sexually Abused Children, Julie B Kaplow, Erin Hall, Karestan C Koenen, Kenneth A Dodge, Lisa Amaya-Jackson

Faculty, Staff and Students Publications

OBJECTIVE: The goals of this research are to develop and test a prospective model of attention problems in sexually abused children that includes fixed variables (e.g., gender), trauma, and disclosure-related pathways.

METHODS: At Time 1, fixed variables, trauma variables, and stress reactions upon disclosure were assessed in 156 children aged 8-13 years. At the Time 2 follow-up (8-36 months following the initial interview), 56 of the children were assessed for attention problems.

RESULTS: A path analysis involving a series of hierarchically nested, ordinary least squares multiple regression analyses indicated two direct paths to attention problems including the child's relationship to …

The Expression Of Microrna Mir-107 Decreases Early In Alzheimer's Disease And May Accelerate Disease Progression Through Regulation Of Β-Site Amyloid Precursor Protein-Cleaving Enzyme 1, Wang-Xia Wang, Bernard W. Rajeev, Arnold J. Stromberg, Na Ren, Guiliang Tang, Qingwei Huang, Isidore Rigoutsos, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are small regulatory RNAs that participate in posttranscriptional gene regulation in a sequence-specific manner. However, little is understood about the role(s) of miRNAs in Alzheimer's disease (AD). We used miRNA expression microarrays on RNA extracted from human brain tissue from the University of Kentucky Alzheimer's Disease Center Brain Bank with near-optimal clinicopathological correlation. Cases were separated into four groups: elderly nondemented with negligible AD-type pathology, nondemented with incipient AD pathology, mild cognitive impairment (MCI) with moderate AD pathology, and AD. Among the AD-related miRNA expression changes, miR-107 was exceptional because miR-107 levels decreased significantly even in patients with …

Adenomatous Polyposis Coli Is Present Near The Minimal Level Required For Accurate Graded Responses To The Wingless Morphogen, Hassina Benchabane, Edward G. Hughes, Carter M. Takacs, Jason R. Baird, Yashi Ahmed

Dartmouth Scholarship

The mechanisms by which the Wingless (Wg) morphogen modulates the activity of the transcriptional activator Armadillo (Arm) to elicit precise, concentration-dependent cellular responses remain uncertain. Arm is targeted for proteolysis by the Axin/Adenomatous polyposis coli (Apc1 and Apc2)/Zeste-white 3 destruction complex, and Wg-dependent inactivation of destruction complex activity is crucial to trigger Arm signaling. In the prevailing model for Wg transduction, only Axin levels limit destruction complex activity, whereas Apc is present in vast excess. To test this model, we reduced Apc activity to different degrees, and analyzed the effects on three concentration-dependent responses to Arm signaling that specify distinct …

Interspecific Hybridization Yields Strategy For South Pacific Filariasis Vector Elimination, Corey L. Brelsfoard, Yves Séchan, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: Lymphatic filariasis (LF) is a leading cause of disability in South Pacific regions, where >96% of the 1.7 million population are at risk of LF infection. As part of current global campaign, mass drug administration (MDA) has effectively reduced lymphatic filiariasis prevalence, but mosquito vector biology can complicate the MDA strategy. In some regions, there is evidence that the goal of LF elimination cannot be attained via MDA alone. Obligate vector mosquitoes provide additional targets for breaking the LF transmission cycle, but existing methods are ineffective for controlling the primary vector throughout much of the South Pacific, Aedes polynesiensis. …

Women's Colposcopy Experience And Preferences: A Mixed Methods Study., Dawn R. Swancutt, Sheila M. Greenfield, Sue Wilson

Peninsula Medical School

BACKGROUND: The colposcopy service is a key component in the UK Cervical Screening Programme. Over 120,000 women are referred to the service annually, however up to 25% of women fail to attend their appointment. Little is known about patients' preferences for colposcopic investigation and treatment. This study aims to investigate women's experience of colposcopy, to identify patients' preferences for aspects of appointments within the colposcopy service, and to make suggestions for service improvement. METHODS/DESIGN: This study has been designed as a two stage, mixed method project. Stage one will involve in-depth interviews with new colposcopy patients to ascertain their experience …

Women's Colposcopy Experience And Preferences: A Mixed Methods Study., Dawn R. Swancutt, Sheila M. Greenfield, Sue Wilson

Peninsula Medical School

BACKGROUND: The colposcopy service is a key component in the UK Cervical Screening Programme. Over 120,000 women are referred to the service annually, however up to 25% of women fail to attend their appointment. Little is known about patients' preferences for colposcopic investigation and treatment. This study aims to investigate women's experience of colposcopy, to identify patients' preferences for aspects of appointments within the colposcopy service, and to make suggestions for service improvement. METHODS/DESIGN: This study has been designed as a two stage, mixed method project. Stage one will involve in-depth interviews with new colposcopy patients to ascertain their experience …

The First (Black) Lady, Verna L. Williams

Faculty Articles and Other Publications

Part I examines the role of First Lady, which has been undertheorized in legal scholarship, and how it promotes privileged white femininity, and in so doing, upholds patriarchy. Part II builds upon that discussion, explaining that the gender and racial norms that contribute to the traditional First Lady trope exemplify the intertwined nature of racism and sexism, which have been used to justify Black subordination. This section also examines how African Americans have embraced gender conformance as a way of attaining acceptance and status within the existing social order, specifically through the "Black lady" construct, which the campaign invoked to …

Interdependent Group Contingency Management For Cocaine-Dependent Methadone Maintenance Patients., Kimberly C Kirby, Mary Louise Kerwin, Carolyn M Carpenedo, Beth J Rosenwasser, Robert S Gardner

College of Science & Mathematics Departmental Research

Contingency management (CM) for drug abstinence has been applied to individuals independently even when delivered in groups. We developed a group CM intervention in which the behavior of a single, randomly selected, anonymous individual determined reinforcement delivery for the entire group. We also compared contingencies placed only on cocaine abstinence (CA) versus one of four behaviors (CA, treatment attendance, group CM attendance, and methadone compliance) selected randomly at each drawing. Two groups were formed with 22 cocaine-dependent community-based methadone patients and exposed to both CA and multiple behavior (MB) conditions in a reversal design counterbalanced across groups for exposure order. …

Foreign-Body Reaction Mimicking Postneurosurgical Infection After Cranioplasty, David Brett-Major, Sean M. Baraniak, Jonathan E. Gilhooly, Rebecca L. Christensen, Gerald T. Grant, Rocco A. Armonda, Anuradha Ganesan

Journal Articles: Epidemiology

The case of a 57-year-old woman who suffered a fall is presented. After a polymethyl malacrylate revision cranioplasty, she presented with signs, symptoms, and intraoperative findings consistent with postneurosurgical infection. Dural foreign-body reaction was diagnosed, and parenteral antibiotic therapy was discontinued successfully.

Nonobstetric Laparoscopy Versus Laparotomy During Pregnancy: Maternal And Fetal Outcomes, Jeannine Ruby

Yale Medicine Thesis Digital Library

The purpose of this study was to compare maternal and fetal outcomes between nonobstetric laparoscopy and laparotomy during pregnancy at Yale-New Haven Hospital. A retrospective chart review was conducted of all nonobstetric intraabdominal surgeries during pregnancy at Yale-New Haven Hospital between 1987 and 2007. Of 159 potential cases, 103 cases (57 laparoscopies, 46 laparotomies) fit the criteria for analysis. Data were collected for the maternal surgical admission, maternal delivery admission, and infant outcome for both groups, and were then analyzed using Statistical Analysis Software (SAS) Version 9.1. There was no difference in age or BMI between groups. Mean gestational age …

Distinguishing Post-Treatment Changes From Recurrent Disease In Cholangiocarcinoma: A Case Report., Timothy N Showalter, A Omer Nawaz, Frederick M Fellin, Pramila R Anne, Ernest L Rosato, Adam P Dicker

Department of Radiation Oncology Faculty Papers

INTRODUCTION: Three-dimensional techniques for radiotherapy have expanded possibilities for partial volume liver radiotherapy. Characteristic, transient radiographic changes can occur in the absence of clinical radiation-induced liver disease after hepatic radiotherapy and must be distinguished from local recurrence. CASE PRESENTATION: In this report, we describe computed tomography changes after chemoradiotherapy for cholangiocarcinoma as an example of collaboration to determine the clinical significance of the radiographic finding. CONCLUSION: Because of improved three-dimensional, conformal radiotherapy techniques, consultation across disciplines may be necessary to interpret post-treatment imaging findings.

Upa Is Upregulated By High Dose Celecoxib In Women At Increased Risk Of Developing Breast Cancer., Wenyi Qin, Weizhu Zhu, John E Hewett, George Rottinghaus, Yin-Chieh Chen, John T Flynn, Beth Kliethermes, Ferdinando Mannello, Edward R Sauter

Department of Physiology Faculty Papers

BACKGROUND: While increased urokinase-type plasminogen activator (uPA) expression in breast cancer tissue is directly associated with poor prognosis, recent evidence suggests that uPA overexpression may suppress tumor growth and prolong survival. Celecoxib has been shown to have antiangiogenic and antiproliferative properties. We sought to determine if uPA, PA inhibitor (PAI)-1 and prostaglandin (PG)E2 expression in nipple aspirate fluid (NAF) and uPA and PGE2 expression in plasma were altered by celecoxib dose and concentration in women at increased breast cancer risk.

METHODS: NAF and plasma samples were collected in women at increased breast cancer risk before and 2 weeks after taking …

One-Year Treatment With Mometasone Furoate In Chronic Obstructive Pulmonary Disease, Peter M.A. Calverley, Stephen I. Rennard, Harold S. Nelson, Jill P. Karpel, Eduardo H. Abbate, Paul Stryszak, Heribert Staudinger

Journal Articles: Pulmonary & Critical Care Med

Many patients with chronic obstructive pulmonary disease (COPD) are treated with twice daily (BID) inhaled corticosteroids (ICS). This study evaluated whether daily PM mometasone furoate administered via a dry powder inhaler (MF-DPI) was equally effective compared to twice daily dosing.In a 52-week, randomized, double-blind, placebo-controlled study, 911 subjects with moderate-to-severe COPD managed without ICS received MF-DPI 800 microg QD PM, MF-DPI 400 microg BID, or placebo. The change from baseline in postbronchodilator forced expiratory volume in 1 second (FEV1), total COPD symptom scores, and health status as well as the percentage of subjects with a COPD exacerbation were assessed. Adverse …

Obesity, Hypertension, And Mental Health Evaluation In Adolescents: A Comprehensive Approach, Stefan G. Kiessling, Kimberly K. Mcclanahan, Hatim A. Omar

Pediatrics Faculty Publications

The global epidemic of childhood and adolescent obesity in developing and developed countries has become a major public health concern. Given the relation between obesity and hypertension as documented in several landmark studies, it is no surprise that as the prevalence of obesity has increased in the pediatric population, the rates of hypertension have also increased substantially. Hypertension is one of the most important risk factors for cardiovascular diseases and stroke; therefore, evaluation and initiation of appropriate treatment are extremely important in the pediatric population. Evaluation for secondary causes of hypertension, including renovascular, renoparenchymal, and endocrine disease is the approach …

Bone Stress Injury Of The Ankle In Professional Ballet Dancers Seen On Mri., Ilan Elias, Adam C Zoga, Steven M Raikin, Judith R Peterson, Marcus P Besser, William B Morrison, Mark E Schweitzer

Department of Orthopaedic Surgery Faculty Papers

BACKGROUND: Ballet dancers have been shown to have a relatively high incidence of stress fractures of the foot and ankle. It was our objective to examine MR imaging patterns of bone marrow edema (BME) in the ankles of high performance professional ballet dancers, to evaluate clinical relevance. METHODS: MR Imaging was performed on 12 ankles of 11 active professional ballet dancers (6 female, 5 male; mean age 24 years, range 19 to 32). Individuals were imaged on a 0.2 T or 1.5 T MRI units. Images were evaluated by two musculoskeletal radiologists and one orthopaedic surgeon in consensus for location …

Correlates Of Tobacco Cessation Counseling Among Hispanic Physicians In The Us: A Cross-Sectional Survey Study, Francisco G Soto Mas, Héctor G Balcázar, Julia Valderrama Alberola, Chiehwen Ed Hsu

Faculty, Staff and Student Publications

BACKGROUND: Physician advice is an important motivator for attempting to stop smoking. However, physicians' lack of intervention with smokers has only modestly improved in the last decade. Although the literature includes extensive research in the area of the smoking intervention practices of clinicians, few studies have focused on Hispanic physicians. The purpose of this study was to explore the correlates of tobacco cessation counseling practices among Hispanic physicians in the US. METHODS: Data were collected through a validated survey instrument among a cross-sectional sample of self-reported Hispanic physicians practicing in New Mexico, and who were members of the New Mexico …

Eomesodermin, A Target Gene Of Pou4f2, Is Required For Retinal Ganglion Cell And Optic Nerve Development In The Mouse, Chai-An Mao, Takae Kiyama, Ping Pan, Yasuhide Furuta, Anna-Katerina Hadjantonakis, William H Klein

Faculty, Staff and Student Publications

The mechanisms regulating retinal ganglion cell (RGC) development are crucial for retinogenesis and for the establishment of normal vision. However, these mechanisms are only vaguely understood. RGCs are the first neuronal lineage to segregate from pluripotent progenitors in the developing retina. As output neurons, RGCs display developmental features very distinct from those of the other retinal cell types. To better understand RGC development, we have previously constructed a gene regulatory network featuring a hierarchical cascade of transcription factors that ultimately controls the expression of downstream effector genes. This has revealed the existence of a Pou domain transcription factor, Pou4f2, that …

Aging Predisposes Oocytes To Meiotic Nondisjunction When The Cohesin Subunit Smc1 Is Reduced, Vijayalakshmi V. Subramanian, Sharon E. Bickel

Dartmouth Scholarship

In humans, meiotic chromosome segregation errors increase dramatically as women age, but the molecular defects responsible are largely unknown. Cohesion along the arms of meiotic sister chromatids provides an evolutionarily conserved mechanism to keep recombinant chromosomes associated until anaphase I. One attractive hypothesis to explain age- dependent nondisjunction (NDJ) is that loss of cohesion over time causes recombinant homologues to dissociate prematurely and segregate randomly during the first meiotic division. Using Drosophila as a model system, we have tested this hypothesis and observe a significant increase in meiosis I NDJ in experimentally aged Drosophila oocytes when the cohesin protein SMC1 …

Searching For The Majority: Algorithms Of Voluntary Control, Jin Fan, Kevin G. Guise, Xun Liu, Hongbin Wang

Faculty, Staff and Student Publications

Voluntary control of information processing is crucial to allocate resources and prioritize the processes that are most important under a given situation; the algorithms underlying such control, however, are often not clear. We investigated possible algorithms of control for the performance of the majority function, in which participants searched for and identified one of two alternative categories (left or right pointing arrows) as composing the majority in each stimulus set. We manipulated the amount (set size of 1, 3, and 5) and content (ratio of left and right pointing arrows within a set) of the inputs to test competing hypotheses …