Dual position locking joint design for a medical walker

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 19).In this thesis we analyzed a joint created for a medical walker currently in the prototyping stage of development. The walker is designed to help a user stand up from a seated position. The joint holds two legs of the walker together in an 'x' shape. It must be able to lock in two positions and support the full weight of the user while he or she is getting up. We looked at four different locking mechanisms including a spring loaded pull pin, a friction bearing, a clutch, and an electronic solenoid. After weighing the pros and cons of each mechanism we recommend and present a design using the pull pin. In order to determine the strength and deflection of the loaded pin we modeled it both as a cantilevered beam, and a simply supported beam with three points of contact. We compared the hand calculations to FEA of solid models and found that modeling the pin as a simply supported beam is more accurate than the cantilever representation.by Eric M. Beecher.S.B

The Grizzly, November 19, 1991

Founders\u27 Day Excitement • Grizzly Network Career Day • Women\u27s Choices • Volksmarching • Louisiana Election • Service Opportunities for Students • The European Situation • Jonas Salk Addresses Founders Day Convocation • Dr. Takats Awarded the Clamer Chair • Wellness Services Proposal • U.S.G.A. Minutes • Ursinus Continues Helping Habitat • Turkey Drive Needs You • Zack: The Man, The Myth, The Statue • Hocus Pocus a Success • Ursinus Students in Community Production of Gypsy • Movie Review: Hamlet • Battle of the Bands • Rollins Rocks Lower Lounge • Branker Tours to St. Petersburg • CAB Trip to New York • Writing in Good Taste • Magic: One Trick Too Many • Letters: Faculty Members Speak Out; GALA Replies to Letter; Call for Diversity; Publishing the Truth?; Student Reaction to Ronning; Response to Black Hole ; Students React to Social Life • No More Crap! • Filling in the Black Hole • One Professor\u27s Awakening • Lady Bears End Season • Men\u27s Lacrosse Awaits Chance • Women Swimmers Wash Out Washington • Spinella Takes Over as Head Coach of Basketball Team • Dickinson Defeats the Bearshttps://digitalcommons.ursinus.edu/grizzlynews/1284/thumbnail.jp

Competition and Combative Advertising: An Historical Analysis

Fred K. Beard (PhD, University of Oklahoma) is a professor of advertising in the Gaylord College of Journalism and Mass Communication, University of Oklahoma. His research interests include comparative advertising, advertising humor, and advertising history. His work has appeared in the Journal of Advertising, the Journal of Advertising Research, the Journal of Business Ethics, the Journal of Business Research, Journalism History, the Journal of Historical Research in Marketing, the Journal of Macromarketing, and the Journal of Marketing Communications, among others.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Role of Metabolic Genes in Blood Aluminum Concentrations of Jamaican Children with and without Autism Spectrum Disorder

Aluminum is a neurotoxic metal with known health effects in animals and humans. Glutathione-S-transferase (GST) genes and enzymes play a major role in detoxification of several heavy metals. Besides a direct relationship with oxidative stress; aluminum decreases GST enzyme activities. Using data from 116 Jamaican children; age 2–8 years; with Autism Spectrum Disorder (ASD) and 116 sex- and age-matched typically developing (TD) children; we investigated the association of polymorphisms in three GST genes (GSTP1; GSTM1; and GSTT1) with mean blood aluminum concentrations in children with and without ASD. Using log-transformed blood aluminum concentration as the dependent variable in a linear regression model; we assessed the additive and interactive effects of ASD status and polymorphisms in the three aforementioned GST genes in relation to blood aluminum concentrations. Although none of the additive effects were statistically significant (all p > 0.16); we observed a marginally significant interaction between GSTP1 Ile105Val (rs1695) and ASD status (p = 0.07); even after controlling for parental education level and consumption of avocado; root vegetables; and tuna (canned fish). Our findings indicate a significantly lower (p < 0.03) adjusted geometric mean blood aluminum concentration for TD children who had the Val/Val genotype (14.57 µg/L); compared with those with Ile/Ile or Ile/Val genotypes who had an adjusted geometric mean of 23.75 µg/L. However; this difference was not statistically significant among the ASD cases (p = 0.76). Our findings indicate that ASD status may be a potential effect modifier when assessing the association between GSTP1 rs1695 and blood aluminum concentrations among Jamaican children. These findings require replication in other populations

Metabolomics of primary cutaneous melanoma and matched adjacent extratumoral microenvironment.

BackgroundMelanoma causes the vast majority of deaths attributable to skin cancer, largely due to its propensity for metastasis. To date, few studies have examined molecular changes between primary cutaneous melanoma and adjacent putatively normal skin. To broaden temporal inferences related to initiation of disease, we performed a metabolomics investigation of primary melanoma and matched extratumoral microenvironment (EM) tissues; and, to make inferences about progressive disease, we also compared unmatched metastatic melanoma tissues to EM tissues.MethodsUltra-high performance liquid chromatography-mass spectrometry-based metabolic profiling was performed on frozen human tissues.ResultsWe observed 824 metabolites as differentially abundant among 33 matched tissue samples, and 1,118 metabolites as differentially abundant between metastatic melanoma (n = 46) and EM (n = 34) after false discovery rate (FDR) adjustment (pConclusionsOverall, pathway-based results significantly distinguished melanoma tissues from EM in the metabolism of: ascorbate and aldarate, propanoate, tryptophan, histidine, and pyrimidine. Within pathways, the majority of individual metabolite abundances observed in comparisons of primary melanoma vs. EM and metastatic melanoma vs. EM were directionally consistent. This observed concordance suggests most identified compounds are implicated in the initiation or maintenance of melanoma

Role of Metabolic Genes in Blood Arsenic Concentrations of Jamaican Children with and without Autism Spectrum Disorder

Arsenic is a toxic metalloid with known adverse effects on human health. Glutathione-S-transferase (GST) genes, including GSTT1, GSTP1, and GSTM1, play a major role in detoxification and metabolism of xenobiotics. We investigated the association between GST genotypes and whole blood arsenic concentrations (BASC) in Jamaican children with and without autism spectrum disorder (ASD). We used data from 100 ASD cases and their 1:1 age- and sex-matched typically developing (TD) controls (age 2–8 years) from Jamaica. Using log-transformed BASC as the dependent variable in a General Linear Model, we observed a significant interaction between GSTP1 and ASD case status while controlling for several confounding variables. However, for GSTT1 and GSTM1 we did not observe any significant associations with BASC. Our findings indicate that TD children who had the Ile/Ile or Ile/Val genotype for GSTP1 had a significantly higher geometric mean BASC than those with genotype Val/Val (3.67 µg/L vs. 2.69 µg/L, p < 0.01). Although, among the ASD cases, this difference was not statistically significant, the direction of the observed difference was consistent with that of the TD control children. These findings suggest a possible role of GSTP1 in the detoxification of arsenic

Cytotype variation and allopolyploidy in North American species of the Sphagnum subsecundum complex (Sphagnaceae)

Allopolyploid speciation is likely the predominant mode of sympatric speciation in plants. The Sphagnum subsecundum complex includes six species in North America. Three have haploid gametophytes, and three are thought to have diploid gametophytes. Microsatellite analyses indicated that some plants of S. inundatum and S. lescurii are heterozygous at most loci, but others have only one allele at each locus. Flow cytometry and Feulgen staining showed that heterozygous plants have twice the genome size as plants with one allele per locus; thus, microsatellite patterns can be used to survey the distribution and abundance of haploid and diploid gametophytes. Microsatellite analyses also revealed that S. carolinianum is consistently diploid, but S. lescurii and S. inundatum include both haploid and diploid populations. The frequency of diploid plants in S. lescurii increases with latitude. In an analysis of one population of S. lescurii , both cytotypes co-occurred but were genetically differentiated with no evidence of interbreeding. The degree of genetic differentiation showed that the diploids were not derived from simple genome duplication of the local haploids. Heterozygosity appears to be fi xed or nearly so in diploids, strongly suggesting that although morphologically indistinguishable from the haploids, they are derived by allopolyploidy