55 research outputs found
Examining mechanical properties of single acetaminophen crystal using nanoindentation methods
No full textThe pharmaceutical industry incurs substantial loss in revenue and consumer confidence with inefficient manufacturing practices. Large scale processing of organic compounds is challenging due to its sensitivity to environmental conditions and the unpredictable breakage behavior of tablets under applied stress. Tablet compaction and particle size reduction through milling induces variability in the end product. Variability in powder flow, stress induced transformation in polymorphic compounds, re-crystallization after compaction, and lack of content uniformity are some factors that translate into poor product quality. These challenges can be partially resolved by a better understanding of mechanical properties of crystalline pharmaceutical materials at single particle level. The endeavor of this study was to understand the breakage behavior of various planes of a single Acetaminophen crystal using nanoindentation instrumentation. The results of the study indicated that the Acetaminophen crystal is anisotropic with respect to hardness and Young’s modulus values. Analysis of the load-depth curve, discontinuities on the loading and unloading cycle were observed, as well as pop-in events during constant load intervals. Furthermore, the frequency of pop-in events on the loading depth curve was found to correlate with the elasticity of the planes in question. It was also apparent that the organic compound was sensitive to environmental conditions. Varying strain rates effects different planes of the same crystal and also in adhesion reflected sensitivity to environmental conditions. The exact mechanism by which the crystal deforms is still unknown. However it is theorized that it could be through partial dislocations and crack propagations.M.S.Includes bibliographical referencesby Hiral Parik
Predictive value of performance-based physical function measures for osteoarthritis-related health outcomes and response to a physical activity intervention
No full textWhite, Daniel K.Background: Over 14 million Americans have symptomatic knee osteoarthritis (OA), which has no cure. Knee OA is a leading cause of functional limitation such as difficulty walking and getting up from a chair, which can be addressed by rehabilitation. However, less than 14% of people with knee OA receive rehabilitation. One reason for low referrals may be the inability to identify those that are in need. Performance-based measures of physical function that identify functional limitation are a potential means to select such individuals. However, clinical assessment of performance-based measures is not part of the routine practice for knee OA. The purpose of this dissertation was to investigate the predictive value of selected clinically feasible performance-based measures with future health outcomes in order to better identify who may be possible candidates for rehabilitation. ☐ Objective: The long-term goal of this work is to identify individuals with knee OA who may benefit from rehabilitation. The overall objective of this dissertation was to investigate if performance-based physical function measures predict OA-related health outcomes (Aims 1 to 3) in adults with knee OA and response to physical therapist led physical activity intervention in adults after total knee replacement (TKR) (Exploratory aim). ☐ Methods: A publicly available large knee OA-related dataset, the Osteoarthritis Initiative (OAI) was used to answer research questions in Aims 1 to 3. The primary study exposures were physical function measures i.e., 1) walking speed measured using a 20-m walk test and 2) repeated chair stands measured using a five times sit-to-stand test. The main study outcomes were 1) physical activity measured using accelerometers, 2) time to all-cause mortality, and 3) time to total knee replacement. For the exploratory aim, we used data from the on-going randomized clinical trial, where individuals post TKR who underwent physical therapy were recruited. ☐ Results: Thresholds of physical function measures indicative of physical inability to walk at least 6000 steps/day were identified in Aim 1. These thresholds may indicate when people with knee OA need rehabilitation to address underlying functional limitation such as impaired endurance, to minimize the risk of future poor health and increase the ability to be physically active. The thresholds on the physical function measures may serve as a clinical target for health professionals. We found that physical function measures assessed at one time-point may be sufficient to gauge mortality risk rather than being measured repeatedly over time. The key finding from Aim 3 was that walking speed was a robust predictor for all-cause mortality in older as well as middle-aged adults with knee OA. Thus, walking speed may be a simple indicator of health in adults with knee OA. Health care professionals may use walking speed to assess expected health and tailor goals of care for knee OA population. Finally, findings from exploratory aim suggests there may be subgroups of patients post-TKR who experience greater benefit from physical therapist led physical activity intervention. ☐ Conclusion: This dissertation provided preliminary evidence on the predictive value of physical function measures for OA-related health outcomes and response to a physical therapist led physical activity intervention. This evidence of the predictive value will provide healthcare professionals with meaningful clinical thresholds on the performance-based measures to assess functional limitation in adults with knee OA. These thresholds will not only aid in clinical decision making by telling clinicians, which patients may need rehabilitation to address functional limitation but also identify candidates who are ready for a physical activity intervention vs. those who may need other interventions such as rehabilitation first to address functional limitation and/or weight management.Ph.D.University of Delaware, Biomechanics and Movement Science Progra
Geographic Disparity in Health Insurance
No full textPurpose: The purpose of this study is to identify factors associated with having adequate health insurance for children with special health care needs (CSHCN) differ by geographic region. Methods: The proposed analysis was conducted on the 2009-2010 databases of the NS-CSHCN using SAS which accounted for complex survey weighting and sampling design. The analysis included examining the overall distributions of variables using means and frequencies. Distributions of variables were examined for those who had any kind of health insurance and those who did not. Differences in whether having health insurance or not by region were analyzed using chi-square test and logistic regressions were performed. Odds ratios and 95% CIs were examined. Results: Out of total population, 10110 were insured for entire year while 919 were insured at some point during the year. Education level, family structure and financial condition of the family have significant effect on the insurance status of CSHCN. Based on chi square analysis, education level of the household had significant effect on insurance status of CSHCN in northeast and south and west region while family structure, number of missed school days of CSHCN, Family financial burden was significant for all region. Odds ratio obtained from logistic regression where individuals who were uninsured was used as reference. Thus, odds of having insurance were higher in individuals with higher education in all the regions. Odds of CSHCN being insured was significantly lesser in northeast, south for Hispanics while was significantly higher in west for blacks compared to white non- Hispanics. Odds of CSHCN being insured was significantly lesser in midwest, south in family consisted of only mother and was significantly lesser in northeast in family consisted of parent stepfamily when compared to either biological or adopted parents. Odds of CSHCN being insured was significantly higher in midwest if child’s problems never affected ability to do compared to those where their ability was usually affected. Odds of CSHCN being insured was significantly higher in midwest, northeast, south in family with no financial burden compared to who had financial burden. Conclusion: Policies should be directed to increase the educational awareness, focus on Hispanic groups for insurance, expand the insurance plans that will accommodate the families having financial burden
Letter to the Editor on “Physical Activity Promotes Gait Improvement in Patients With Total Knee Arthroplasty”
No full textStudy of La0.7Sr0.3Mn0.94Co0.06O3 /x nano Al2O3 (x = 0%, 4%) composite for structural and electrical transport properties
No full textElectrical transport and magnetoresistive properties of La0.7Sr0.3Mn1-xCoxO3 (LSMCO) (x = 0, 0.06) & LSMCO+4% micro Al2O3 composite
No full textEffect of second introduced phase on magnetic and magnetotransport properties of (1-x)La0.7Sr0.3Mn0.9Co0.1O3/x% Ag (x=0%, 2%, 4%) nanocomposites
No full textA Study to Compare the Efficacy between Active Self Stretching and Self PNF Stretching on Hamstring Flexibility among Normal Individuals
No full textArthritis Care Res (Hoboken)
No full textObjective.This study examined the racial and ethnic differences in individuals with self-reported and doctor-diagnosed arthritis, severe joint pain, and provider counseling for physical activity among US adults with arthritis.Methods.We estimated prevalence by race and ethnicity among 31,997 adults aged 6518 years in the 2019 National Health Interview Survey. We used multiple logistic regression models to investigate associations between outcomes and race and ethnicity.Results.Compared with non-Hispanic White adults (22.9%), we found a significantly higher age-adjusted prevalence of arthritis among American Indian/Alaska Native adults (30.3%). Among adults with arthritis, higher age-adjusted prevalence of severe joint pain among American Indian/Alaska Native (39.1%), non-Hispanic Black (36.4%), and Hispanic adults (35.7% vs 22.5% [White]) and higher provider counseling for physical activity among non-Hispanic Black adults (58.9% vs 52.1% [White]) were observed and could not be fully explained by differences in socioeconomic factors, body mass index, depression history, and comorbid conditions. Additional models also containing inability to pay medical bills and food insecurity did not explain racial and ethnic differences.Conclusion.Our findings highlight a need for multilevel interventions to mitigate social and environmental barriers to physical activity and eliminate disparities in individuals with arthritis and severe joint pain.CC999999/ImCDC/Intramural CDC HHSUnited States
The evolution of diet in the Lamprophiidae
No full textA dissertation submitted in fulfilment of the requirements of the degree of Master of Science to the School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa .
July 2017.Studying feeding biology in a phylogenetic context helps elucidate the factors that significantly influenced the evolutionary history of organisms. The snake lineage is one of the most morphologically and ecologically diverse clades of vertebrates due to a variety of traits (e.g. venom, body shape, gape size and habitat use) that have enabled their exceptional radiation. Recently, the Deep History Hypothesis (DHH) has been used to explain how divergence, deep in the evolutionary history of snakes, has resulted in present day niche preferences. The Competition-Predation Hypothesis (CPH) contrastingly attributes current ecological traits to recent species interactions. Diet has been a key factor in shaping snake diversity and ecology, and it has often been used as a proxy to understand current snake community structure and evolutionary trends in snakes.
I tested the validity of the two evolutionary hypotheses in the Lamprophiidae, a family of primarily African snakes. Furthermore, the evolution of lifestyle, fang types and body size in the Lamprophiidae was examined. Having sourced dietary data for ~300 species, a Hierarchical Cluster Analysis was performed, to group diet into eight broad clusters. A generalist diet comprised of lizards, aquatic vertebrates, small mammals, snakes and reptile eggs, was characteristic of 46% of extant species. Stochastic Character Mapping was performed to generate 50 possible evolutionary hypotheses, the majority of which suggested a generalist ancestral feeding condition with a tendency towards specialisation. Although the generalist feeding trait has largely been retained in many extant lamprophids, some species have a more specialised diet. From the phylogenetic reconstruction, it is evident that the ancestral lamprophid consumed a generalist diet in a terrestrial environment with a relatively small body size (400-600 mm) and possessed back fangs. Body size and fang morphology were correlated with diet indicating that these selective pressures have influenced the variety in prey consumption.
A phylogenetic signal from Pagel’s lambda confirmed the divergence in diet while traits such as lifestyle, fang types and body size were constrained. Thus, the validity of DHH and CPH depends on the characters assessed and in this case, a combination of historical and contemporary influences is responsible for shaping the lamprophid community as a whole. The divergence in diet in the lamprophids is most likely influenced by competition or predation, as their interactions with other species within their habitat could be responsible for shaping their diet. This proves to be the case for the lamprophidae, however, studies on other
groups of snakes, in different regions of the world have found that phylogeny is more influential on diet patterns. This study shows the importance in understanding ecological factors as a determinant of community ecology.
Key words: Divergent evolution, snake ecology, morphological trait reconstructionLG201
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