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Researchers have explored using the internet and social media to recruit participants to specific research projects. Less systematic work has been done to inform the engagement of large populations in virtual communities to advance clinical and translational science. We report on our first step to use social media to engage Minnesota residents by studying the willingness of participants to engage in a virtual (Facebook) community about the concepts of health and health-related research.
Data was collected at the 2018 Minnesota State Fair using a cross-sectional, 46-item survey with assessment including socio-demographics and willingness to engage in a Facebook group for health-related research. Quantitative analysis included univariate, bivariate and multivariate analyses. Content analysis was used to generate themes from open-ended survey responses.
500 people completed the survey; after data cleaning 418 participant responses informed this report. A majority were younger than age 50 (73%), female (66%), and married/partnered (54%). Overall, 46% of participants agreed/strongly agreed they are willing to join the Facebook group. Multivariate logistic regression identified social media use over the past 6 months as the sole variable independently associated with willingness to join the Facebook group (once a day vs. never or rarely OR=1.82 (0.86, 3.88), several hours a day vs. never or rarely OR=2.17 (1.17, 4.02, overall p-value 0.048).
Facebook holds potential for reaching a broader community, democratizing access to and engagement with clinical and translational research. Social media infrastructure and content could be disseminated to other institutions with Clinical and Translational Science Awards.
OBJECTIVES/SPECIFIC AIMS: Virtual communities are an untested method to enhance community engagement in biomedical research. Our CTSA Hubs collaborated to assess receptivity to engage in a statewide Facebook (FB) group. METHODS/STUDY POPULATION: Cross-sectional online survey administered via iPads at the MN State Fair in 2018 to adults aged 18+ years residing in MN assessed demographics, social media use, interest in participating in a FB group for biomedical research; and open-ended questions on health topics of interest, and what would keep people engaged in this group. RESULTS/ANTICIPATED RESULTS: Respondents (N=487) were 21% racial minorities and 65% female sex. Most (87%, n=422) had created a personal FB profile. Of these, the proportion who agreed/strongly agreed was: 57% that the FB group sounded interesting, 45% were interested in being part of it, 41% were willing to share it with others, 62% that it would allow the community’s thoughts/ideas to be heard and 59% wanted to learn about opportunities to participate in research on health topics they care about. Using content analysis, the top 3 health topics people wanted to learn about were chronic disease and prevention, wellness, and mental health. Top ways to keep people engaged were providing personable, relevant health information; and interactive bi-directional discussions. DISCUSSION/SIGNIFICANCE OF IMPACT: Findings will inform development of a FB group to engage diverse populations in biomedical research.
To assess the feasibility and acceptability of a beverage intervention in Hispanic adults.
Eligible individuals identified as Hispanic, were 18–64 years old and had BMI 30·0–50·0 kg/m2. Participants were randomized 2:2:1 to one of three beverages: Mediterranean lemonade (ML), green tea (GT) or flavoured water control (FW). After a 2-week washout period, participants were asked to consume 32 oz (946 ml) of study beverage daily for 6 weeks and avoid other sources of tea, citrus, juice and sweetened beverages; water was permissible. Fasting blood samples were collected at baseline and 8 weeks to assess primary and secondary efficacy outcomes.
Tucson, AZ, USA.
Fifty-two participants were recruited over 6 months; fifty were randomized (twenty-one ML, nineteen GT, ten FW). Study population mean (sd) age 44·6 (sd 10·2) years, BMI 35·9 (4·6) kg/m2; 78 % female.
Forty-four (88 %) completed the 8-week assessment. Self-reported adherence was high. No significant change (95 % CI) in total cholesterol (mg/dl) from baseline was shown −1·7 (−14·2, 10·9), −3·9 (−17·2, 9·4) and −13·2 (−30·2, 3·8) for ML, GT and FW, respectively. Mean change in HDL-cholesterol (mg/dl) −2·3 (−5·3, 0·7; ML), −1·0 (−4·2, 2·2; GT), −3·9 (−8·0, 0·2; FW) and LDL-cholesterol (mg/dl) 0·2 (−11·3, 11·8; ML), 0·5 (−11·4, 12·4; GT), −9·8 (−25·0, 5·4; FW) were also non-significant. Fasting glucose (mg/dl) increased significantly by 5·2 (2·6, 7·9; ML) and 3·3 (0·58, 6·4; GT). No significant change in HbA1c was demonstrated. Due to the small sample size, potential confounders and effect modifiers were not investigated.
Recruitment and retention figures indicate that a larger-scale trial is feasible; however, favourable changes in cardiometabolic biomarkers were not demonstrated.
Two machines: The human body and the vehicle motor are made of structural and functional, natural and man-produced materials. They generate energy by chemical oxidation of two fluids: ethanol and gasoline. The characteristics of these fluids: a nutritive beverage and a fuel, providing motion to the vehicle, are described. The damage due to diseases in the body by excessive ethanol consumption and deterioration of the motor by corrosion are treated by means of preventive and curative methods: body rehabilitation and car repair, maintaining both machines in permanent, healthy, working operation. The chemical reactions of ethanol oxidation and gasoline combustion and their effects on the machines and their materials are presented, illustrated and discussed.
Were synthesized four new hybrid hardener agents type amino tertiary functionalized with allyl groups from : l, 6-Hexanediamine, Diethylenetriamine, Trietilentriamine and Tris (2-aminoethyl) amine, using the basic nucleophilic substitution mechanism, replacing bromide by amino tertiary group in the presence of tetrabutylammonium bromide as phase transfer agent, producing allyl amine corresponding: ALA-4, ALA-5, ALA-6 and TRIS respectively, which were evaluated as a hardening of epoxy resin DGEBA through photopolymerization process by UV ligth curing, adding a 10, 20 and 40% molar percentage of hybrid materials and the thiol corresponding to carry out the thiol-ene reaction (TMP TMP, PTKMP) with DMPA as initiator. The resinic materials obtained, were evaluated by the technique of dynamic mechanical analysis (DMA) at a heating rate of 5° C/min in a range from - 50° C to 150° C in nitrogen atmosphere. The formulations with hybrid hardening agent ALA 4- 20% -PTKMP and TRIS 10% -PTKMP were the materials with modulus 2289, 2971 Mpa and tgs of 102,103°C, respectively.
A complex cerium bearing oxide, Gd2Ce2O7 was synthesized in order to simulate Pu in a fluorite derivative oxide. X-ray diffraction (XRD) data was collected using a lab diffractometer at room temperature and analyzed by Rietveld refinement method using the xnd program. The diffraction pattern obtained from the material could be indexed as a C-type cubic bixbyite crystal structure however several peaks showed peak broadening and could not be accounted for within the single-phase bixbyite model. A full pattern refinement, assuming a possible existence of short order disordered bixbyite regions within an average disordered fluorite phase gave a good fit with the experimental data, providing an estimate for correlation length of those bixbyite regions. Transmission electron microscopy confirms the existence of these correlated domains of disordered bixbyite type phase inside a defect fluorite lattice. Understanding the extent of these domains as a function of composition and the thermal history of the samples may have a profound effect on our understanding of miscibility gaps in Re2O3-CeO2 phase diagrams. These effects could be eventually exploited to design materials with increased radiation resistance, a desired feature for oxide matrices where actinides can be safely disposed.
In this paper, an optimization design of a 6 DOF parallel measuring system is analyzed. First, a closed form direct kinematics formulation based on Cayley–Menger determinants is considered in the objective function, in order to measure the manipulator singularities, then an estimation of distribution algorithm is proposed to solve the optimization problem. It is shown that the evolutionary algorithm can find close to optimal solutions for minimum pose error estimation. Additionally, these global optimizers significantly reduce the computational burden in comparison with exhaustive search and other global optimization techniques. The sensitivity of the pose error estimation in the prescribed robots' workspace is analyzed and used to guide a designer in choosing the best structural configuration. Numerical examples are discussed to show the feasibility of the proposed optimization methodology.
We present the preliminary results of the measurements of longitudinal magnetic field of the massive white dwarf 1658+441. This star have an hydrogen pure atmosphere (e.g. Dupuis & Chayer, 2003). We have observed the target in a total of 18 hrs during 3 consecutive nights in June 2010 and one more in May 2011. The data was acquired with a prototypical spectropolarimeter at the San Pedro Martir Telescope in Mexico. We have tested the magnetic field measurements with our instrument using the famous Babcock's star obtaining consistent results with previous studies. For our object of study, the WD 1658+441, we have measured variable intensities of the longitudinal magnetic field of Blong = 720 kG that oscillates with an amplitude of 130 kG.
In this paper the spore-crystal complex of Bacillus thuringiensis var. israelensis (Bti) was immobilized by the sol-gel process in a hybrid polymer using as precursors the inorganic tetraethyl orthosilicate (TEOS) and the organic Polydimethylsiloxane (PDMS); in order to combine the advantages of both materials in a hybrid matrix to improve aspects such as the thermal stability, the hydrophobic properties and the porosity. Bti produces different crystals during sporulation phase; these are of protein nature and are used as bio-insecticides. It is important to mention that the insecticide attack is specific to the mosquito larva that causes dengue and black flies. The samples were characterized to ensure viability by performing growth kinetics with fermentations immersed in a flask, this microbial growth was monitored by dry weight, glucose consumption and characterized by Fourier Transform Infrared Spectroscopy (FTIR) to observe the interaction of materials with spore-crystal complex.
Botulism is a severe neuroparalytic disorder that can be potentially life-threatening. In Barcelona, Spain, no outbreaks had been reported in the past 25 years. However, in September 2011, two outbreaks occurred involving two different families. A rare case of Clostridium baratii which produced a neurotoxin F outbreak was detected in five family members who had shared lunch, and several days before that another family was affected by C. botulinum toxin A which was probably present in homemade pâté.
In the present work, the authors examine two computational approaches that can be used to study flexible flapping systems. For illustration, a fully coupled interaction of a fluid system with a flapping profile performing harmonic flapping kinematics is studied. In one approach, the fluid model is based on the Navier-Stokes equations for viscous incompressible flow, where all spatio-temporal scales are directly resolved by means of Direct Numerical Simulations (DNS). In the other approach, the fluid model is an inviscid, potential flow model, based on the unsteady vortex lattice method (UVLM). In the UVLM model, the focus is on vortex structures and the fluid dynamics is treated as a vortex kinematics problem, whereas with the DNS model, one is able to form a more detailed picture of the flapping physics. The UVLM based approach, although coarse from a modeling standpoint, is computationally inexpensive compared to the DNS based approach. This comparative study is motivated by the hypothesis that flapping related phenomena are primarily determined by vortex interactions and viscous effects play a secondary role, which could mean that a UVLM based approach could be suitable for design purposes and/or used as a predictive tool. In most of the cases studied, the UVLM based approach produces a good approximation. Apart from aerodynamic load comparisons, features of the system dynamics generated by using the two computational approaches are also compared. The authors also discuss limitations of both approaches.
A novel biopolymer derived from diallyl sucrose (A2S) and dithiotreitol (DTT) was prepared by means of Thiol-Ene Photopolymerization. A2S was prepared by alkylating the sucrose with allyl bromide, using water as solvent. After purification by column chromatography, a fraction (F2A2S) with 94% diallyl sucrose (A2S), 4 % of triallyl sucrose (A3S) and 2 % of monoallyl sucrose (A1S) was obtained. This fraction was subsequently photopolymerized with Dithiothreitol (DTT) which is a difunctional thiol. Kinetics of photopolymerization were determined by means of Real-Time Infrared spectroscopy. It was found that the photocurable formulation with DTT and F2A2S, polymerized rapidly in the presence and absence of a photoinitiator, at low intensities of UV light. After bulk polymerization, a flexible material with high elastic modulus and a Tg of 30 °C was obtained. Besides, the polymer displayed moderate water absorbance properties as a result of the presence of multiple hydroxyl groups. This property was pH dependent with maximum absorbance at pH=14. The polymer degraded rapidly under acidic conditions
Polycrystalline δ-phase Sc4Zr3O12 was irradiated with 200 keV Ne+ ions at cryogenic temperature to fluences ranging from 2 × 1018 to 1 × 1021 Ne/m2. Irradiation-induced structural evolution was examined by using grazing incidence x-ray diffraction and cross-sectional transmission electron microscopy. An order-to-disorder (O-D) crystal structure transformation (from an ordered δ-phase to a disordered, fluorite phase) was observed to initiate by a fluence of 2 × 1018 Ne/m2, corresponding to a peak ballistic damage dose of ∼0.075 displacements per atom. This displacement damage dose is much lower than the O-D transformation dose threshold found in previous heavy ion irradiation experiments on δ-Sc4Zr3O12 [J.A. Valdez et al., Nucl. Instrum. Methods B250, 148 (2006); K.E. Sickafus et al., Nat. Mater.6, 217 (2007)]. In this study, we contrast the O-D transformation efficiency of the light Ne ions used in these experiments, to the heavy (Kr) ions used previously, and interpret the differences in terms of enhanced damage efficiency for light ions (greater fraction of surviving defects per defect produced). To better quantify this surviving defect phenomenon, we also present new, additional ion irradiation results on δ-Sc4Zr3O12, obtained from 300 keV Kr2+ and 100 keV He+ ion irradiation experiments.
To assess the association of time spent viewing television, videos and video games with measures of fat mass (BMI) and distribution (triceps and subscapular skinfold thicknesses (TSF, SSF)).
Cross-sectional validated survey, self-administered to students to assess screen time (television, videos and video games) and lifestyle variables. Trained personnel obtained anthropometry. The association of screen time with fat mass and distribution, stratified by sex, was modelled with multivariable linear regression analysis, adjusting for potential confounders and correlation of observations within schools.
State of Morelos, Mexico.
Males (n 3519) and females (n 5613) aged 11 to 18 years attending urban and rural schools in Morelos.
In males, screen time of >5 h/d compared with <2 h/d was significantly associated with a 0·13 (95 % CI 0·04, 0·23) higher BMI Z-score, 0·73 mm (95 % CI 0·24, 1·22) higher SSF and 1·08 mm (95 % CI 0·36, 1·81) higher TSF. The positive association of screen time with SSF was strongest in males aged 11–12 years. Sexual maturity appeared to modify the association in females; a positive association between screen time and SSF was observed in those who had not undergone menarche (P for trend = 0·04) but not among sexually mature females (P for trend = 0·75).
Screen time is associated with fat mass and distribution among adolescent males in Mexico. Maturational tempo appears to affect the relationship of screen time with adiposity in boys and girls. Findings suggest that obesity preventive interventions in the Mexican context should explore strategies to reduce screen time among youths in early adolescence.
Background. Recognition can be normalized in schizophrenia by providing patients with semantic organizational strategies through a levels-of-processing (LOP) framework. However, patients may rely primarily on familiarity effects, making recognition less sensitive than source monitoring to the strength of the episodic memory trace. The current study investigates whether providing semantic organizational strategies can also normalize patients' internal source-monitoring performance.
Method. Sixteen clinically stable medicated patients with schizophrenia and 15 demographically matched healthy controls were asked to identify the source of remembered words following an LOP-encoding paradigm in which they alternated between processing words on a ‘shallow’ perceptual versus a ‘deep’ semantic level. A multinomial analysis provided orthogonal measures of item recognition and source discrimination, and bootstrapping generated variance to allow for parametric analyses. LOP and group effects were tested by contrasting recognition and source-monitoring parameters for words that had been encoded during deep versus shallow processing conditions.
Results. As in a previous study there were no group differences in LOP effects on recognition performance, with patients and controls benefiting equally from deep versus shallow processing. Although there were no group differences in internal source monitoring, only controls had significantly better performance for words processed during the deep encoding condition. Patient performance did not correlate with clinical symptoms or medication dose.
Conclusions. Providing a deep processing semantic encoding strategy significantly improved patients' recognition performance only. The lack of a significant LOP effect on internal source monitoring in patients may reflect subtle problems in the relational binding of semantic information that are independent of strategic memory processes.