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Articles 1 - 30 of 115
Full-Text Articles in Medicine and Health Sciences
Characterizing The Performance And Behaviors Of Runners Using Twitter, Qian He, Emmanuel Agu, Diane Strong, Bengisu Tulu, Peder Pedersen
Characterizing The Performance And Behaviors Of Runners Using Twitter, Qian He, Emmanuel Agu, Diane Strong, Bengisu Tulu, Peder Pedersen
Emmanuel O. Agu
Running is a popular physical activity that improves physical and mental wellbeing. Unfortunately, up-to- date information about runners’ performance and psychological wellbeing is limited. Many questions remain unanswered, such as how far and how fast runners typically run, their preferred running times and frequencies, how long new runners persist before dropping out, and what factors cause runners to quit. Without hard data, establishing patterns of runner behavior and mitigating the challenges they face are difficult. Collecting data manually from large numbers of runners for research studies is costly and time consuming. Emerging Social Networking Services (SNS) and fitness tracking devices …
Detection Of Diabetic Foot Ulcers Using Svm Based Classification, Lei Wang, Peder Pedersen, Diane Strong, Bengisu Tulu, Emmanuel Agu, Qian He, Ronald Ignotz, Raymond Dunn, David Harlan, Sherry Pagoto
Detection Of Diabetic Foot Ulcers Using Svm Based Classification, Lei Wang, Peder Pedersen, Diane Strong, Bengisu Tulu, Emmanuel Agu, Qian He, Ronald Ignotz, Raymond Dunn, David Harlan, Sherry Pagoto
Emmanuel O. Agu
Diabetic foot ulcers represent a significant health issue, for both patients’ quality of life and healthcare system costs. Currently, wound care is mainly based on visual assessment of wound size, which suffers from lack of accuracy and consistency. Hence, a more quantitative and computer-based method is needed. Supervised machine learning based object recognition is an attractive option, using training sample images with boundaries labeled by experienced clinicians. We use forty sample images collected from the UMASS Wound Clinic by tracking 8 subjects over 6 months with a smartphone camera. To maintain a consistent imaging environment and facilitate the capture process …
A Context-Aware Activity Recommendation Smartphone Application To Mitigate Sedentary Lifestyles, Qian He, Emmanuel Agu
A Context-Aware Activity Recommendation Smartphone Application To Mitigate Sedentary Lifestyles, Qian He, Emmanuel Agu
Emmanuel O. Agu
A sedentary lifestyle involves irregular or no physical activity. In this kind of lifestyle, people’s activities do not increase their energy expenditure substantially above resting levels. Long periods of sitting, lying, watching television, playing video games, and using the computer are typical examples. Energy expenditures at 1.0-1.5 Metabolic Equivalent Units (METs) are considered sedentary behaviors. A recent study of sedentary lifestyles found that the length of sedentary times is associated with an increased risk of diabetes, cardiovascular disease, and cardiovascular and all-cause mortality. In this study, we developed a smartphone application called “On11”, which continuously tracks and informs the user …
Effects Of Cost Sharing On Seeking Care For Serious And Minor Symptoms. Results Of A Randomized Controlled Trial, Martin Shapiro, John Ware, Cathy Sherbourne
Effects Of Cost Sharing On Seeking Care For Serious And Minor Symptoms. Results Of A Randomized Controlled Trial, Martin Shapiro, John Ware, Cathy Sherbourne
Martin Shapiro
To estimate the effect of cost sharing on seeking care for serious and minor symptoms, we analyzed data for 3539 persons aged 17 to 61 from the Rand Health Insurance Experiment. Participants were randomly assigned to a free-care group or to insurance plans requiring them to pay part of the costs (cost-sharing group). Annual surveys were administered to determine if participants had serious and minor symptoms during the preceding month and whether they saw a physician. Serious symptoms were judged by a panel of physicians to warrant care in most instances; minor symptoms were judged neither to be severe nor …
Disease Will Limit Future Food Supply From The Global Crustacean Fishery And Aquaculture Sectors, G. Stentiford, D. Neil, E. Peeler, J. Shields, H. Small, T. Flegel, J. Vlak, B. Jones, F. Morado, S. Moss, J. Lotz, Lyric Bartholomay, D. Behringer, C. Hauton, D. Lightner
Disease Will Limit Future Food Supply From The Global Crustacean Fishery And Aquaculture Sectors, G. Stentiford, D. Neil, E. Peeler, J. Shields, H. Small, T. Flegel, J. Vlak, B. Jones, F. Morado, S. Moss, J. Lotz, Lyric Bartholomay, D. Behringer, C. Hauton, D. Lightner
Lyric Bartholomay
Seafood is a highly traded food commodity. Farmed and captured crustaceans contribute a significant proportion with annual production exceeding 10 M metric tonnes with first sale value of $40bn. The sector is dominated by farmed tropical marine shrimp, the fastest growing sector of the global aquaculture industry. It is significant in supporting rural livelihoods and alleviating poverty in producing nations within Asia and Latin America while forming an increasing contribution to aquatic food supply in more developed countries. Nations with marine borders often also support important marine fisheries for crustaceans that are regionally traded as live animals and commodity products. …
Study Of Potential Risk Of Dengue Disease Outbreak In Sri Lanka Using Gis And Statistical Modelling, Sumith Pathirana, Masato Kawabata, Rohitha Goonatilake
Study Of Potential Risk Of Dengue Disease Outbreak In Sri Lanka Using Gis And Statistical Modelling, Sumith Pathirana, Masato Kawabata, Rohitha Goonatilake
Adjunct Associate Professor Sumith Pathirana
The increasing incidence of dengue fever has become a priority health issue for Sri Lanka. Recent dengue outbreaks in Sri Lanka show two trends: yearly increase of total number of dengue incidence and increasing dengue outbreaks outside the endemic urbanised areas in the south and the west. Identification of factors responsible for dengue outbreaks and the mapping of potential risk areas in Sri Lanka are long overdue. This study examines the association between weekly rainfall patterns and dengue outbreaks in the western province between 2000 and 2004. Methods: The study develops a model to quantitatively assess the relationship between rainfall …
Evaluation Of Animal Model Research, Kenneth J. Shapiro
Evaluation Of Animal Model Research, Kenneth J. Shapiro
Kenneth J. Shapiro, PhD
It is argued that a concept of evaluation of animal models that is broader and more useful than validation is available. Productive generativity refers to the degree to which a model furthers understanding and leads to more-effective treatment interventions. Results of the application of this novel evaluative frame to several animal models of eating disorders show that this animal-based research has not been productive. The question of the relation between clinic and animal laboratory is discussed.
Designing For Positive Health Affect: Decoupling Negative Emotion And Health Monitoring Technologies, Tammy R. Toscos, Kay Connelly, Yvonne Rogers
Designing For Positive Health Affect: Decoupling Negative Emotion And Health Monitoring Technologies, Tammy R. Toscos, Kay Connelly, Yvonne Rogers
Tammy R Toscos
Through various health-focused technology projects, we discovered that the emotional response to technology was related to uptake and sustained use of health monitoring technologies. In this paper we present a case study of how we synthesized constructs of social cognitive theory, technology as experience, and diabetes management guidelines as a framework for making design recommendations for blood glucose monitoring technology that address the emotional response of users. We suggest applying this theoretical lens for design may help attend to emotional responses of users in an effort to decouple strong negative emotions that are paired to health monitoring technologies that provide …
Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling
Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling
Tammy R Toscos
Enhanced access and continuity are key components of patient-centered care. Existing studies show that several interventions such as providing same day appointments, walk-in services, after-hours care, and group appointments, have been used to redesign the healthcare systems for improved access to primary care. However, an intervention focusing on a single component of care delivery (i.e. improving access to acute care) might have a negative impact other components of the system (i.e. reduced continuity of care for chronic patients). Therefore, primary care clinics should consider implementing multiple interventions tailored for their patient population needs. We collected rapid ethnography and observations to …
Biography, Julie Elaine N. Irish
Biography, Julie Elaine N. Irish
Julie Elaine Irish
Characterization Of Physical, Spectroscopic And Thermal Properties Of Biofield Treated Biphenyl, Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Rakesh K. Mishra, Snehasis Jana
Characterization Of Physical, Spectroscopic And Thermal Properties Of Biofield Treated Biphenyl, Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Rakesh K. Mishra, Snehasis Jana
Mahendra Kumar Trivedi
Characterization Of Physical, Thermal And Spectral Properties Of Biofield Treated 2,6-Dichlorophenol, Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Rakesh K. Mishra, Snehasis Jana
Characterization Of Physical, Thermal And Spectral Properties Of Biofield Treated 2,6-Dichlorophenol, Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Rakesh K. Mishra, Snehasis Jana
Mahendra Kumar Trivedi
Chromatographic, Spectroscopic, And Thermal Characterization Of Biofield Energy Treated N,N-Dimethylformamide, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
Chromatographic, Spectroscopic, And Thermal Characterization Of Biofield Energy Treated N,N-Dimethylformamide, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
Mahendra Kumar Trivedi
Thermal, Spectroscopic And Chromatographic Characterization Of Biofield Energy Treated Benzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
Thermal, Spectroscopic And Chromatographic Characterization Of Biofield Energy Treated Benzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
Mahendra Kumar Trivedi
Experimental Investigation On Physical, Thermal And Spectroscopic Properties Of 2-Chlorobenzonitrile: Impact Of Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Ragini Singh, Snehasis Jana
Experimental Investigation On Physical, Thermal And Spectroscopic Properties Of 2-Chlorobenzonitrile: Impact Of Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Ragini Singh, Snehasis Jana
Mahendra Kumar Trivedi
Physicochemical And Spectroscopic Characteristics Of Biofield Treated P-Chlorobenzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Khemraj Bairwa, Snehasis Jana
Physicochemical And Spectroscopic Characteristics Of Biofield Treated P-Chlorobenzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Khemraj Bairwa, Snehasis Jana
Mahendra Kumar Trivedi
C–N Bond Rotation And E–Z Isomerism In Some N-Benzyl-N-Methylcarbamoyl Chlorides: A Dft Study, Michael Horwath, Vladimir Benin
C–N Bond Rotation And E–Z Isomerism In Some N-Benzyl-N-Methylcarbamoyl Chlorides: A Dft Study, Michael Horwath, Vladimir Benin
Vladimir Benin
The current report presents the first theoretical study of the restricted CN bond rotation in carbamoyl chlorides. Several N-benzyl-N-methylcarbamoyl chlorides were investigated, with varying pattern of substitution in the aromatic ring. Optimizations and frequency calculations were conducted employing DFT at the B3LYP/6-31+G(d) level of theory. Each of the studied structures exhibits a pair of rotamers (s-Z and s-E), generated upon rotation around the C(O)N bond. The s-E isomer is the global minimum in every case, but the preference for it is usually less than 1 kcal/mol. Two possible transition state structures were identified for the rotamer interconversion: TSsyn and TSanti, …
Preparation And Characterization Of Some Substituted Benzyl N-Nitrosocarbamates Containing An N-2-(Methylthio)Ethyl Or A Bis(2-Aminoethyl)Sulfide Functionality, Satya Venkata, Eric Shamo, Vladimir Benin
Preparation And Characterization Of Some Substituted Benzyl N-Nitrosocarbamates Containing An N-2-(Methylthio)Ethyl Or A Bis(2-Aminoethyl)Sulfide Functionality, Satya Venkata, Eric Shamo, Vladimir Benin
Vladimir Benin
The synthesis and characterization of some substituted benzyl N-nitrosocarbamates with an N-2-(methylthio)ethyl or a bis(2-aminoethyl)sulfide functionality is reported, as a part of a long-term goal to design and prepare novel photolabile structures that could be used as substances for controlled release of alkylating and/or crosslinking agents. The synthesis was accomplished by reaction of benzyl chloroformates with the corresponding amines, resulting in the preparation of carbamates. The latter were subsequently nitrosated, utilizing two different N-nitrosation methods, to yield the target structures.
The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin
The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin
Vladimir Benin
The tetrafluoroborate salt of 4-methoxybenzyl N-2-(dimethylamino)ethyl-N-nitrosocarbamate was prepared in two steps, via the corresponding carbamate. Its crystal structure is monoclinic, space group P21/c. The unit cell dimensions are: a = 19.499(8) Å, b = 5.877(3) Å, c = 15.757(7) Å, α = 90°, β = 110.019(7)°, γ = 90°, V = 1696.5(12) Å3, Z = 4. The structure exhibits an unexpected, pseudo-gauche conformation with respect to the C2–C3 bond, due to a stabilizing hydrogen bond between the carbonyl oxygen (O1) and the hydrogen atom at the trialkylammonium center (H3n), with a distance between them of 2.37 Å. DFT calculations on …
A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin
A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin
Vladimir Benin
The title compound, sodium bis(6-carboxy-1-hydroxy-3-oxo-1,3-dihydro-2,1-benzoxaborol-1-yl)oxidanium, Na+·C16H15B2O13-, was prepared in two steps from 2-bromo-p-xylene. Its crystal structure was determined at 140 K and has triclinic (P) symmetry. The compound presents a unique structural motif, including two units of the cyclic anhydride of boronoterephthalic acid, joined by a protonated, and thereby trivalent, oxonium center. Association in the crystal is realized by complementary hydrogen bonding of the carboxyl groups, as well as by coordination of the sodium cations to the oxygen centers on the five-membered rings.
Secondary N-Nitrosocarbamate Anions: Structure And Alkylation Reactions. A Dft Study, Vladimir Benin
Secondary N-Nitrosocarbamate Anions: Structure And Alkylation Reactions. A Dft Study, Vladimir Benin
Vladimir Benin
The current article reports theoretical studies (DFT: B3LYP/6-31+G(d)) on the structure and alkylation reactions of the anions of some secondary N-nitrosocarbamates, a class of ambident nucleophiles whose chemistry has been little explored. Several anions (1–4), with an increasing size of the carbamate alkyl (aryl) group were investigated, in an attempt to establish the influence of the size of that group on the thermal stability and regioselectivity of alkylation of the title anions. The conclusion is that thermal stability and the mode of reaction are affected significantly only in the presence of very large and branched carbamate groups. The thermal decomposition …
Preparation Of Phosphonoterephthalic Acids Via Palladium-Catalyzed Coupling Of Aromatic Iodoesters, Nathaniel Ivan, Vladimir Benin, Alexander Morgan
Preparation Of Phosphonoterephthalic Acids Via Palladium-Catalyzed Coupling Of Aromatic Iodoesters, Nathaniel Ivan, Vladimir Benin, Alexander Morgan
Vladimir Benin
The current article reports in detail the preparation of two phosphonoterephthalic acids: 2-phosphonoterephthalic acid (1) and 2,5-diphosphonoterephthalic acid (2). Efficient, scalable syntheses have been developed for both compounds based on Pd-catalyzed coupling reactions of iodinated terephthalate esters. Phosphonoterephthalic acids are potentially useful as flame-retardant additives or as monomers for the construction of acid-pendant polymer chains.
Preparation Of Some Substituted Terephthalic Acids, Susanna Branion, Vladimir Benin
Preparation Of Some Substituted Terephthalic Acids, Susanna Branion, Vladimir Benin
Vladimir Benin
We report in detail the preparation of two substituted terephthalic acids: 2‐sulfomethylterephthalic acid (1) and 2‐phosphonoterephthalic acid (2). Efficient, short syntheses have been developed for both compounds. They are potentially useful monomers for construction of acid‐pendant polymer chains.
Theoretical Investigation Of A Reported Antibiotic From The 'Miracle Tree' Moringa Oleifera, Michael Horwath, Vladimir Benin
Theoretical Investigation Of A Reported Antibiotic From The 'Miracle Tree' Moringa Oleifera, Michael Horwath, Vladimir Benin
Vladimir Benin
Moringa oleifera, sometimes called the “Miracle Tree,” has received international attention for its potential to improve health in impoverished tropical areas. In addition to high vitamin content in the leaves and pods, the tree contains compounds with antioxidant and antibacterial properties. This study focused on the theoretical investigation of the suggested structure of one antibacterial compound, “pterygospermin,” whose existence was proposed after some studies of the roots of M. oleifera. The structure of pterygospermin was first proposed by a research group working in the 1950s, but later studies have not found evidence of this compound and have instead attributed the …
Synthesis And Flammability Testing Of Epoxy Functionalized Phosphorous-Based Flame Retardants, Vladimir Benin, Xuemei Cui, Alexander Morgan, Karl Seiwert
Synthesis And Flammability Testing Of Epoxy Functionalized Phosphorous-Based Flame Retardants, Vladimir Benin, Xuemei Cui, Alexander Morgan, Karl Seiwert
Vladimir Benin
Several potential new phosphorus-containing flame retardant molecules were evaluated for heat release reduction potential by incorporation of the molecules into a polyurethane, generated from methylene diphenyl diisocyanate and 1,3-propane diol. The heat release reduction potential of these substances was evaluated using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods to qualitatively evaluate their potential reactivity into the polyurethane prior to heat release testing. The functionality of the flame retardants was epoxide based that would potentially react with the diol during polyurethane synthesis. Flammability testing …
Synthesis And Flame Retardant Testing Of New Boronated And Phosphonated Aromatic Compounds, Vladimir Benin, Sravanthi Durganala, Alexander Morgan
Synthesis And Flame Retardant Testing Of New Boronated And Phosphonated Aromatic Compounds, Vladimir Benin, Sravanthi Durganala, Alexander Morgan
Vladimir Benin
The present report describes the preparation and use of some dimethyl terephthalate derivatives in transition metal-catalyzed coupling reactions to produce new reactive flame retardants. Dimethyl iodoterephthalate and dimethyl 2,5-diiodoterephthalate were successfully employed in the preparation of phosphonic and boronic esters and acids. The latter were tested for heat release with a microcombustion calorimeter (ASTM D7309) to determine the potential for heat release reduction of these flame retardant molecules. The results showed that the addition of boronic or phosphonic acids greatly lowered the heat release, due to a condensed phase (char formation) mechanism. Adding ester groups to the boronic acids or …
Heat Release Of Polyurethanes Containing Potential Flame Retardants Based On Boron And Phosphorus Chemistries, Vladimir Benin, Bastien Gardelle, Alexander Morgan
Heat Release Of Polyurethanes Containing Potential Flame Retardants Based On Boron And Phosphorus Chemistries, Vladimir Benin, Bastien Gardelle, Alexander Morgan
Vladimir Benin
Using a polyurethane of methylene diphenyl isocyanate and 1,3-propane diol, several new non-halogenated aromatic boron and phosphorus flame retardants were evaluated for heat release reduction potential using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods, and were then analyzed via spectroscopic methods to determine if the flame retardant was still present in the final product. PCFC testing on the resulting products showed that the flame retardant molecule can have different effects on heat release depending upon how it is mixed into the polyurethane. Some …
Preparation, Characterization And Dft Studies Of Some New N-Nitrosocarbamates And N-Nitrosoureas, Ragavan Narayanan, Helene Hedian, Eric Shamo, Vladimir Benin
Preparation, Characterization And Dft Studies Of Some New N-Nitrosocarbamates And N-Nitrosoureas, Ragavan Narayanan, Helene Hedian, Eric Shamo, Vladimir Benin
Vladimir Benin
We are presenting the preparation, characterization and density functional theory (DFT) studies {B3LYP/6-31+G(d)) of several reiated classes of N-nitrosocarbamates and N-nitrosoureas. The iong-range goal is the design and preparation of compounds, which would undergo photochemical or hydrolytic decomposition, to yield stabilized cyclic cations that can serve as alkylating agents at various nucleophilic centers, including DNA bases.
Synthesis, Structural Studies And Desilylation Reactions Of Some N-2-(Trimethylsilyl)Ethyl-N-Nitrosocarbamates, Arpitha Thakkalapally, Vladimir Benin
Synthesis, Structural Studies And Desilylation Reactions Of Some N-2-(Trimethylsilyl)Ethyl-N-Nitrosocarbamates, Arpitha Thakkalapally, Vladimir Benin
Vladimir Benin
The present report describes the preparation and characterization of several N-2-(trimethylsilyl)ethyl-N-nitrosocarbamates, designed as precursors to thermally unstable secondary N-nitrosocarbamate anions via fluoride-assisted cleavage. X-ray structural studies demonstrate that the core N-nitrosocarbamate moiety has a nearly planar geometry, with an s-E orientation at the N–N bond. DFT calculations (B3LYP/6-31+G(d)) reproduce accurately the structural features of the title compounds and detailed conformational analysis at the same level of theory addresses the long-standing issue of preferred geometries for three classes of related structures: N-nitrosocarbamates, N-nitrosoureas and N-nitrosoamides. Desilylation studies demonstrate that both the …
Reactions Of Methyl Perfluoroalkyl Ethers With Isopropyl Alcohol: Experimental And Theoretical Studies, Howard Knachel, Vladimir Benin, Chadwick Barklay, Janine C. Birkbeck, Billy D. Faubion, William E. Moddeman
Reactions Of Methyl Perfluoroalkyl Ethers With Isopropyl Alcohol: Experimental And Theoretical Studies, Howard Knachel, Vladimir Benin, Chadwick Barklay, Janine C. Birkbeck, Billy D. Faubion, William E. Moddeman
Vladimir Benin
The reaction of an isomeric mixture of the methyl perfluoroalkyl ether, C4F9OCH3 (Novec-7100), in the presence of isopropyl alcohol (IPA) and/or water has been studied by measuring the rate of product formation using an ion-selective electrode (ISE) for fluoride ion, Karl Fisher coulometric titrations for water, and 1H and 19F NMR spectroscopy for product identification and rate studies. The results showed the methyl perfluoroalkyl ether to be very stable with products forming at the rate of ∼1 ppm per year at a laboratory temperature of 20 °C. Measurements over the temperature range of 6° to 100 °C were made on …