bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of clinical and microbiological results of photodynamic therapy as support in non-surgical treatment of periodontitis – preliminary study
Authors: Maj Adrian , Kusiak Aida , Garbacz Katarzyna , Ziółkowska-Klinkosz Marta
Published: May 2019

Introduction. Photodynamic therapy is supportive method of non-surgical treatment of periodontitis. The aim of the study was the assessment of photodynamic therapy impact on periodontal disease clinical parameters with a particular emphasis on microbiological aspects during periodontal treatment.
Material and methods. The research was conducted on seven healthy patients aged 26-
55 years. All the patients were treated with a non-surgical (SRP) periodontal treatment.
Then, the assisted photodynamic therapy was applied in selected pockets. Samples of the material obtained from periodontal pockets before and after the treatment were cultured in a microbiological laboratory.
Results. After the introduced therapy the clinical improvement of periodontal disease was observed in the majority (6/7) of patients taking part in the study. There obtained the elimination of inflammation to 85.7% of the patients. Periodontal pocket depths have deteriorated from 0.5 to 3.0 mm in comparison to the pre-treatment values. The overall number of bacteria compared to the pre-treatment value was reduced. In addition, there was noticed a decrease in the number of periopathogens. Control samples showed a vivid dominance of the physiological flora.
Conclusions. The non-surgical treatment of periodontitis in combination with the
supportive action of photodynamic therapy has promising therapeutic effects by reducing the inflammation and decreasing the depth of periodontal pockets. The change in the ratio of periopathogens to physiological flora may indicate the restoration and maintenance of the state balance in periodontal pockets for patients with periodontitis.
Cover: Full Image
Authors: Rast Rina
Published: May 2019

Messier 101, also known as the Pinwheel galaxy, is a face-on spiral galaxy 21 million light-years away. Its small companion, NGC 5474, is a peculiar dwarf galaxy being distorted by the gravitational influence of the Pinwheel. This is a stacked image of 30x180 second exposures using an 11" RASA telescope and colour CMOS camera on the roof of the UofS Physics Building.  My collaborators were Brennan Rodgers (who helped with data collection and processing) and Emery Dlugan (helped with data collection). It was done "for fun," and so no supervisors were involved. However, the telescopes on the roof of the Physics Building are regularly used by students in Astronomy lab classes for research in photometry and spectroscopy.
Keanekaragaman Hymenoptera Parasitoid Pada Pertanaman Padi di Dataran Rendah dan Dataran Tinggi Sumatera Barat
Authors: Agro Editor
Published: May 2019

Hymenoptera parasitoids are potential as biological agents for controlling insect pests of rice plant. Diversity of hymenoptera parasitoids was studied in low and high land rice plant in west Sumatra. Objective of research was to obtain information about diversity and equity of hymenoptera parasitoids in ecosystem of low and high land rice. A survey was conducted using purposive random sampling. Collection of insects was done using insects net and yellow pan traps. The number of hymenoptera parasitoids found in rice plant in the lowland was 114 individuals which belonged to 10 families and 29 species, and in highland there were 112 individuals which belonged to 13 families and 31 species. Diversity and evenness index of hymenoptera parasitoid species were slightly higher in highland (3.198 and 0.922)  compared to low land (3.029 and 0.890)
Pergeseran Fungsi Legislasi DPRD dalam Pembentukan Peraturan Daerah Untuk Memperkuat Kedudukan DPRD dalam Penyelenggaraan Pemerintahan Daerah
Authors: Radjab Dasril
Published: May 2019

That with the presence of refomasi against the holding of the Government of the Republic of Indonesia, there was a significant change towards the function of legislation. If prior to the reformation by the UU No. 5 of the year 1974 the main legislation function is in the hands of the head Area, then after the Reformation was gradually shifted to the functions of DPRD, while the head of the Region carry out the Change was discussed along with Representatives The People Of The Region. Peregeseran the function of legislation to DPRD, then the seat of DPRD from both the political and juridical aspects become increasingly powerful as the element that organizes local governance. Disaran implementation of the function of legislation should run properly in the full sense of responsibility as well as follow all stages of the formation of local regulations that cover the stages of planning, drafting, discussion, enactment, assignment, and peyebarluasan
Gagasan constitutional Complaint Sebagai kewenangan Baru Mahkamah Konstitusi dalam Perlindungan Hak Konstitusional
Authors: Yanti Herma
Published: May 2019

The formation of the Constitutional Court (MK) as a guardian of the constitution is basically intended to guarantee the implementation of the constitutional provisions (the 1945 Constitution) seriously in the administration of the state, as well as to realize constitutional supremacy in the Indonesian legal state. One of the contents of the 1945 Constitution is a guarantee of protection of basic human and citizen rights that have been accepted as constitutional rights. Because of that, the Court also functions to guarantee the implementation of these constitutional rights. However, for violations of constitutional rights included in the case of constitutional complaints submitted to the Constitutional Court, the resolution has not yet been dealt with, because their authority has not been regulated in the 1945 Constitution, so the idea of making constitutional complaints develops as the Constitutional Court's new authority. This paper discusses how the Constitutional Court's authority in protecting constitutional rights is based on the 1945 Constitution, and what about the ideas that emerged to add constitutional complaint as the Constitutional Court's new authority in protecting constitutional rights. In accordance with the problem, this research is a normative legal research using a legal approach accompanied by a comparative legal approach. The results of the study show that the authority of the Constitutional Court in protecting constitutional rights is only limited to the authority to examine the Law against the Constitution. From the ideas that emerged, there were three possibilities for entering constitutional complaint on the authority of the Constitutional Court, namely through changes to the 1945 Constitution, through changes to the Law and through interpretation by the Constitutional Court itself. Of the three ideas, the most appropriate is to change the 1945 Constitution so that it can provide a strong foundation in providing protection for citizens' constitutional rights.
CREATING A DECOLONISED CURRICULUM TO ADDRESS FOOD INSECURITY AMONG UNIVERSITY STUDENTS
Authors: Adebayo Oluwakemi Ayodeji , Mudaly Ronicka
Published: May 2019

A plethora of debates about intellectual imagination regarding decolonised curriculum development has dominated the South African higher education discourses. There is a need to purge Africa of the marginalisation that has been perpetuated by curricula established during the past century. The aim of this research was to add a practical dimension to this discourse, by altering traditional curriculum activities in a biology module, in order to address the issue of food insecurity among university students. In this qualitative inquiry, the following questions were asked: “How can pre-service teachers engage with decolonised curricular activities, in order to address food insecurity among students?” and “What are the consequences of pre-service teachers’ engagement with decolonised curricular activities which respond to food insecurity?” Thirty-six pre-service biology teachers and 12 non-biology university students were purposively selected to participate in a food gardening activity. Data were generated using individual interviews, focus group interviews and the development of portfolios. Findings revealed that pre-service teachers’ consciousness of the social reality of food insecure students was raised, and their feelings of empowerment to enable others, and themselves, to become self-reliant, were enhanced through decolonised curricular activities. This is significant because it signalled a freeing of pre-service teachers from material and intellectual shackles which is critical to decolonised thought and action. This research has implications for higher education science teacher education modules, which can incorporate science from Western and indigenous sources, to create transformed curricula which are socially responsive and reflect epistemic justice.
Keywords: decolonised curriculum, food gardening, indigenous knowledge, qualitative methodology, self-reliance, transformation.
AN INNOVATIVE ASSESSMENT METHOD TO ESTABLISH EMPLOYABILITY MAP BASED ON STUDENTS’ LEARNING PORTFOLIO
Authors: Cheng Shu-Chen , Chang Shing-Lin
Published: May 2019

This research focuses on the approach adopted by a university of science and technology in Taiwan (hereinafter the university) to develop students’ employability indices and to explore the questionnaire analyses. The university developed the “Employability Map; E-Map” by weighting the learning hours, which was used to evaluate students’ various employability items over the course of their schooling. Considering it not so appropriate to use students’ credits on courses to be the standard of judgment, the Department of Computer Science & Information Engineering (hereinafter the department) proposed an innovative method to convert the E-Map of weighting by learning achievement to conduct assessments that is more reflection students' employability indices for graduate, and analyzed the questionnaires of alumni and their employers’ various core employability indices. From those questionaires, finding the graduating students and alumni are lack of self-confidentce. The statistical data shall serve as a reference for guiding students at course selection, as well as improving department courses and planning. Keywords: employability indices, employability map, learning achievement, learning portfolio.
EVALUATION OF SELF-EFFICACY IN PROSPECTIVE PRIMARY SCHOOL TEACHERS IN THE CONTEXT OF MATHEMATICS TEACHING
Authors: Dofková Radka
Published: May 2019

Positive perception of one’s efficacy among teachers is a crucial factor affecting the quality of the teaching process. Many research studies suggest that self-efficacy in prospective teachers can be acted upon. It is therefore very important to focus on the preparation of prospective teachers in the context of undergraduate courses. The objective of the research study was to identify the level of self-efficacy among primary pre-service teachers of mathematics. The research sample comprised 77 students of primary teacher training enrolled in two study programmes aged between 21 and 26 years. The results were obtained by means of a newly developed tool Self-Efficacy of Prospective Teachers in Mathematics (SEPTM), which contained 37 items. The results of the research suggest that prospective teachers assess their readiness for future mathematics teaching in a positive way and trust their own abilities to use various teaching methods and procedures.
Keywords: primary math education, prospective math teacher, teacher´s beliefs, teacher’s self-efficacy
TRENDS IN THE M-LEARNING SUBJECT AREA OVER A 15-YEAR PERIOD (2002-2017) USING SCOPUS
Authors: Valencia-Arias Alejandro , Cano Laura Duque , Arango-Botero Diana
Published: May 2019

The current social dynamics perceive education as an impeller of social and economic change. However, there are problems of coverage, relevance and methodology in the educational process, mainly in Higher Education Institutions (HEIs). Recently, tools have emerged that adopt and appropriate ICTS in learning processes, such as mobile learning, which seeks to meet the requirements of mobility, accessibility and interactivity that traditional teaching mechanisms have not covered satisfactorily. Based on the necessity to identify the factors that drive the adoption of mobile learning by different HEIs, this research identifies the factors that encourage the adoption of mobile learning in the institutions. For this, results of an exercise of technological surveillance in indexed database (Scopus) were analyzed by means of scientometric indicators. Some of the most significant factors detected are: preparation of the professor, perceptions and attitudes of students, technological culture, and technological environment that leverages new learning models.
Keywords: bibliometric analysis, high education, mobile learning, research trends.
Discurso do sujeito coletivo das concepções sobre educação permanente em saúde de gestores e cirurgiões-dentistas da atenção primária à saúde
Authors: Maciel Jacques Antonio Cavalcante , Castro-Silva Igor Iuco , Farias Mariana Ramalho de , Vasconcelos Maristela Inês Osawa , Dias Maria Socorro de Araújo , Queiroz Maria Veraci Oliveira
Published: May 2019

Resumo: A Educação Permanente em Saúde (EPS) visa planejamento e execução de ações formativas de profissionais da saúde que atendam às necessidades da população e dos princípios do Sistema Único de Saúde (SUS). O presente estudo buscou caracterizar as concepções dos gestores e cirurgiões-dentistas da Atenção Primária à Saúde sobre EPS. A coleta se deu por entrevista com cirurgiões-dentistas da ESF e com profissionais representantes da gestão das ações de EPS. A análise ocorreu por meio do Discurso do Sujeito Coletivo (DSC) com a elaboração de discursos que representem os discursos dos cirurgiões-dentistas e da gestão. O DSC mais prevalente sobre a concepção de EPS para cirurgiões-dentistas mostrou conceitos que se aproximam da Educação Continuada, diferente da concepção dos gestores. A gestão do trabalho e da educação na saúde com ênfase na valorização profissional e fortalecimento dos vínculos constitui-se determinante para um entendimento e aderência a EPS.Palavras-chave: Educação na Saúde; Odontologia; Atenção Primária à Saúde. Discourse of the collective subject of the conceptions on permanent education in health of managers and dental surgeons of the primary health careAbstract: The Permanent Education in Health (EPS) aims to plan and execute training actions of health professionals that meet the needs of the population and the principles of the Unified Health System (SUS). The present study aimed to characterize the conceptions of dental managers and surgeons of Primary Health Care on EPS. The data collection was by interview with dental surgeons of the ESF and with professional representatives of the management of EPS actions. The analysis took place through the Discourse of the Collective Subject (DSC) with the elaboration of speeches that represent the look of dentists and management. The DSC most prevalent on the design of EPS for dental surgeons showed concepts that approach Continuing Education, different from the conception of the managers. The management of work and education in health with emphasis on professional valorization and strengthening of bonds is a determining factor for an understanding and adherence to the EPS.Keywords: Health Education; Dentistry; Primary Health Care.
Identification of Propionibacterium spp. Isolated from Mihaliç Cheeses by MALDI-TOF MS
Authors: TIRPANCI SİVRİ Göksel , ÖKSÜZ Ömer
Published: May 2019

Propionic acid bacteria (PAB) are responsible for characteristic properties of Mihaliç cheese, which is one of the prevalent traditional cheese produced in Turkey. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been reliable and rapid method for identifying bacterial isolates. The aim of this study was to evaluate the PAB profile of Mihaliç cheese by their identification by MALDI-TOF MS system. In this study, a total of 25 cheese samples were analyzed and 95 isolates were determined as probable PAB based on their morphological characteristics, gram staining, catalase activity and pigment production. All isolates were analyzed by MALDI-TOF MS and 21 of them were belong to PAB. Isolates were identified as Propionibacterium freudenreichii ssp. freudenreichii (57%), Propionibacterium freudenreichii ssp. shermanii (33%) and Propionibacterium thoenii (10%). This study indicates that the diversity of PAB found in Mihaliç cheese can be determined rapidly and economically by MALDI-TOF MS.
Utilizing Machine Learning to Accelerate Automated Assignment of Backbone NMR Data
Authors: Venzke Joel , Mascharka David , Johnson Paxten , Davis Rachel , Roth Katie , Robison Leah , Kilpatrick Adina , Urness Timothy
Published: May 2019

Nuclear magnetic resonance (NMR) spectroscopy is a powerful method for determining three-dimensional structures of biomolecules, including proteins. The protein structure determination process requires measured NMR values to be assigned to specific amino acids in the primary protein sequence. Unfortunately, current manual techniques for the assignment of NMR data are time-consuming and susceptible to error. Many algorithms have been developed to automate the process, with various strengths and weaknesses. The algorithm described in this paper addresses the challenges of previous programs by utilizing machine learning to predict amino acid type, thereby increasing assignment speed. The program also generates place-holders to accommodate missing data and amino acids with unique chemical characteristics, namely proline. Through machine learning and residue-type tagging, the assignment process is greatly sped up, while maintaining high accuracy.

KEYWORDS: Chemical Shift; Machine Learning; NMR; Artificial Intelligence; Proteins; Bioinformatics
Preparation of t-Butyldimethylphosphine Borane and t-Butyldiethylphosphine Borane by Selective Grignard Reagent Substitution of Phosphorus Trichloride
Authors: Butterfield Auston , Prater Matthew , Werner Nathan
Published: May 2019

The synthesis of differentially substituted trialkylphosphine boranes from the selective substitution reaction of Grignard reagents with phosphorus trichloride in a single reaction flask was studied. The reaction temperature, stoichiometric loading of the first equivalent of Grignard reagent and reaction time were found to be important for maximizing the yield and selectivity of the reaction. Reaction conditions were optimized to achieve maximum yield of t-butyldiethylphosphine borane. The optimized conditions were applied to the syntheses of t-butyldiethylphosphine borane and t-butyldimethylphosphine borane, which provided 60% and 62% isolated yields respectively. Products were characterized with mass spectrometry, infrared spectroscopy, 1H, 13C, and 31P nuclear magnetic resonance spectroscopy.

KEYWORDS: Synthesis; Trialkylphosphine; Grignard Reagent; Selective; Substitution Reaction; t-Butyldiethylphosphine Borane; t-Butyldimethylphosphine Borane; Phosphorus Trichloride
Development of Four-Square Fiducial Markers for Analysis of Paper Analytical Devices
Authors: Wilson Jenna , Ricketts Tabitha , Bentley Ian , Misiolek Ewa
Published: May 2019

Fiducial markers are used in image processing to determine locations of interest based on fixed points of reference. There are a number of applications for these markers across various fields ranging from advertising to radiation therapy. The four-square fiducial markers discussed in this manuscript allow for the determination of locations of interest on digital images. These new markers are easily detected, provide information about image orientation, and allow for local color sampling. The markers are intended for use in a pharmaceutical assessment process in which images of colorimetric chemical tests are taken by a smart-phone in the field, uploaded to a database, and analyzed to collect quantitative information about the colors resulting from the tests.
KEYWORDS: Image Processing; Digital Imaging; Fiducial Markers; Image Thresholding; Color Calibration; MATLAB; Paper Analytical Devices
Malate : Quinone Oxidoreductase and Malic Enzyme are required for the Plant Pathogen Pseudomonas syringae pv. tomato DC3000 to Utilize Malate
Authors: Ebert Zabrina , Jacob Preston , Jose Katrina , Fouad Lina , Vercellino Katherine , Van Dorn Steven , Sidiqqi Mahaa , Mellgren Eve
Published: May 2019

Pseudomonas syringae pv. tomato strain DC3000 (DC3000) is a gram-negative bacterial plant pathogen that causes disease on tomato and the model plant Arabidopsis thaliana. Interestingly, previous studies showed that malate:quinone oxidoreductase (Mqo), an enzyme in the citric acid cycle, is required for DC3000 to cause disease on these plants. In addition, growth of DC3000 lacking the mqo gene in minimal medium with malate was significantly delayed, but eventually reached wild-type levels of growth, which is similar to growth in planta. This suggests that malate may be an important carbon source for DC3000. One reason the mqo::KO bacteria may be able to reach wild-type levels of growth in culture and plants is that the DC3000 malic enzyme may be used to complete the citric acid cycle. Our research shows that a mutant strain lacking a functional mqo gene and malic enzyme gene (mqo::KO;ME::pJP) fails to grow in minimal media cultures with malate and has reduced growth in media with citrate, indicating that both Mqo and ME are required for normal growth when utilizing these carbon sources. Future studies looking at growth of this double mutant in plants will identify how important the activities of both of these genes are for DC3000 to cause disease in plants.
KEY WORDS: Malate:quinone Oxidoreductase; Malic Enzyme; MQO; Pseudomonas syringae; Arabidopsis thaliana; Malate; Citrate; DC3000
A Relationship Between Time Perception and State-Anxiety
Authors: Brown James
Published: May 2019

Participants in this study were randomly assigned to one of three interval groups of either one, three, or five minutes. All participants were asked to estimate a group-assigned time interval and complete the state portion of the State Trait Anxiety Inventory (STAI). It was hypothesized that higher levels of state anxiety would cause participants to overestimate the passage of time. It was also hypothesized that shorter interval durations would be estimated more accurately than longer interval durations. Results of a t-test did not support the first hypothesis. Results of a linear trend analysis did support the second hypothesis (P < .05). These results indicate that state-anxiety does not cause the passage of time to be overestimated and that interval duration length affects how accurately time is estimated. Implications of this study are important to the understanding of human time-management ability and time estimation errors.
KEYWORDS: Time estimation; Perception; State-anxiety; Attention; Working memory; Emotion
Modeling Internet Traffic Generations Based on Individual Users and Activities for Telecommunication Applications
Authors: Stoudt Sara , Badian-Pessot Pamela , Ngo Mahop Blanche , Earley Erika , Menter Jordan , Flores Yadira , Williams Danielle , Zhang Weijia , Maharjan Liza , Bao Yixin , Rosenbauer Laura , Nguyen Van , Mendiratta Veena , Tania Nessy
Published: May 2019

A traffic generation model is a stochastic model of the data flow in a communication network. These models are useful during the development of telecommunication technologies and for analyzing the performance and capacity of various protocols,algorithms, and network topologies. We present here two modeling approaches for simulating internet traffic. In our models, we simulate the length and interarrival times of individual packets, the discrete unit of data transfer over the internet. Our first modeling approach is based on fitting data to known theoretical distributions. The second method utilizes empirical copulae and is completely data driven. Our models were based on internet traffic data generated by different individuals performing specific tasks (e.g., web browsing, video streaming, and online gaming). When combined, these models can be used to simulate internet traffic from multiple individuals performing typical tasks.
KEYWORDS: Internet Traffic Simulation; Stochastic Models; Empirical Copula; Cumulative distribution function; Wireshark
Green Chemistry: Comparison of Ionic Liquid vs Conventional Solvent for Indole Alkylation
Authors: Redrico Jonathan , Krstenansky John
Published: May 2019

A comparison of the effectiveness of two synthetic methods was done for a green chemistry method using an ionic liquid-based solvent relative to a conventional method using organic solvents for the N-alkylation of indole. The green method used potassium hydroxide in the ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, followed by addition of the alkyl halide. The conventional method used sodium hydride in dimethylformamide. Possible advantages of the green method would be the use of a non-volatile solvent, the possibility of recycling the solvent, and the use of a less reactive base. However, its reaction yield was lower than for the conventional method, the reagent expense was higher, and recycling and reuse of the ionic solvent require considerable amounts of conventional solvent to clean it up sufficiently for reuse. On a laboratory scale, the ionic liquid method yielded neither a “green” nor an efficiency advantage. It is possible that with optimization on an industrial scale involving solvent reclamation that the green method could realize its promise.
KEYWORDS: Green Chemistry; Sustainable Chemistry; Ionic Liquids; N-alkylation; Indole; Solvent Recycling; Organic Chemistry; 1-Butyl-3-methylimidazolium Tetrafluoroborate; Synthesis
Dynamic Visualization of Time-Based Changes to Data Generated by Reddit.com: The Real Time Conversation Project
Authors: Wang Daniel , Luse Andy , Burkman Jim
Published: May 2019

With the increased amount of data generated by social networking sites there is also increased difficulty in the analysis of this data, including time-based changes, which can provide unique insights in social network analysis. Information visualization is a vital tool in assisting social scientists with analysis of large quantities of data; however, the gathering, formatting, and visualizing of time-related data from social networking sites still remains an obstacle. This research explores the process of gathering time-based data in real time and using dynamic visualization techniques to visualize and analyze time-based changes in data generated by discussions on the social networking site Reddit. The outcome culminates in our deliverable, the Real Time Conversation Project.
KEYWORDS: Visualization; Network Analysis; Social Network; Reddit; Gephi
A Comparative Analysis of the Fitness of Collegiate Dancers as compared to Collegiate Volleyball and Softball Players
Authors: Miller Leanna , Miller III Fred
Published: May 2019

Few studies directly compare the various fitness components of collegiate dancers and athletes in acknowledged sports. The limited studies that do exist fail to consider certain variables or to assess multiple fitness components. The purpose of this study was to provide a more comprehensive comparison of collegiate dancers and collegiate volleyball and softball players. We used multiple fitness components as an indicator of the comparative physical demands of these activities, to assess whether the physical demands of collegiate dance may warrant a comparable level of medical support as afforded to the volleyball and softball players. Thirty dancers and thirty volleyball and softball players were tested using six different measurements of physical fitness commonly used in athletic assessments at universities. A two-tailed independent t-test was performed to determine differences between dancers and athletes in each fitness component. Three tests revealed significant differences between the groups, with the dancers having a lower percent body fat and greater flexibility, and the athletes having greater relative upper body strength. No significant differences were found in relative leg strength, core strength, or estimated VO2max. The results of the current study suggest that dance provides training adaptations equivalent to traditional intermittent sports and thus support the use of similar levels of medical care for collegiate dancers to that afforded to collegiate volleyball and softball players.
KEYWORDS: Physical Fitness; Dance; Dance Medicine; Athletics; Dance Health Benefits
A Comparative Study of All-atom Molecular Dynamics Simulation and Coarse-grained Normal Mode Analysis in Identifying Pre-existing Residue Interaction Networks that Promote Coupled-Domain Dynamics in Escherichia coli Methionyl-tRNA Synthetase
Authors: Fehling Samuel , Strom Alexander , Lehman Brent , Andrews Ryan , Bhattacharyya Sudeep , Hati Sanchita
Published: May 2019

Inter-domain communication plays a key role in the function of modular proteins. Earlier studies have demonstrated that the coupling of domain motions is important in mediating site-to-site communications in modular proteins. In the present study, bioinformatics and molecular simulations were usedto trace “pre-existing” residue-residue interaction networks that mediate coupled-domain dynamics in multi-domain Escherichia coli methionyl-tRNA synthetase (Ec MetRS). In particular, a comparative study was carried out to evaluate the effectiveness of coarse-grained normal mode analysis and all-atom molecular dynamic simulation in predicting pre-existing pathways of inter-domain communications in this enzyme. Integration of dynamic information of residues with their evolutionary features (conserved and coevolved) demonstrated that multiple residue-residue interaction networks exist in Ec MetRS that promote dynamic coupling between the anticodon binding domain and the connective polypeptide I domain, which are > 50Å apart, through correlated motions. Mutation of residues on these pathways have distinct impact on the dynamics and function of this enzyme. Moreover, the present study revealed that the dynamic information obtained from the coarse-grained normal mode analysis is comparable to the atomistic molecular dynamics simulations in predicting the interaction networks that are essential for promoting coupled-domain dynamics in Ec MetRS.
KEYWORDS: Domain-domain Communication; Molecular Dynamics; Methionyl-tRNA Synthetase; Normal Mode Analysis; Coupled-domain Dynamics; Course-grained Normal Mode Analysis; Aminoacyl tRNA Synthetases; Statistical Coupling Analysis
Skewed and Flexible Skewed Distributions: A Modern Look at the Distribution of BMI
Authors: Tran Thao , Wiskow Cara , Aziz Mohammad
Published: May 2019

The purpose of this study is to find distributions that best model body mass index (BMI) data. BMI has become a standard health indicator and numerous studies have been done to examine the distribution of BMI. Due to the skew and bimodal nature, we focus on modeling BMI with flexible skewed distributions. The distributions are fitted to University of Wisconsin–Eau Claire (UWEC) BMI data and to a data obtained from National Health and Nutrition Survey (NHANES). The model parameters are obtained using maximum likelihood estimation method. We compare flexible models to more conventional distributions, such as skew-normal, and skew-t distributions using AIC and BIC and Kolmogorov-Smirnov (K-S) goodness-of-fit test. Our results indicate that the skew-t and Alpha-Skew-Laplace distributions are reasonably competitive when describing unimodal BMI data whereas Alpha-Skew-Laplace and finite mixture of scale mixture of skew-normal and skew-t distributions are better alternatives to both unimodal and bimodal conventional distributions. The results we obtained are useful because we believe the models discussed in ours study will offer a framework for testing features such as bimodality, asymmetry, and robustness of the BMI data, thus providing a more detailed and accurate understanding of the distribution of BMI.
KEYWORDS: Body Mass Index; Skew-normal distribution; Skew-t distribution; Flexible skewed distributions; Mixture distributions; Scale mixture of skew-normal distribution; K-S test
Determination of Fitted Size Distribution for Atmospheric Aerosols
Authors: DuPaul Kaitlin , Whitten Adam
Published: May 2019

A synthetic set of aerosol optical depths (AODs) generated from a standard set of aerosol size distributions was analyzed by a parameter based particle swarm optimization (PBPSO) routine in order to test the reproducibility of the results. Junge and lognormal size distributions were consistently reproduced. Gamma and bimodal distributions showed large variability in solutions. values were used to determine the best subset of possible solutions allowing quantification of parameters with uncertainties when using PBPSO. AODs measured by a sun photometer on a clear day (20160413) and a foggy day (20160508) were then processed by the PBPSO program for both bimodal and lognormal distributions. Results showed that in general the foggy day has smaller values indicating that the PBPSO algorithm is better able to match AODs when there is a larger aerosol load in the atmosphere. The bimodal distribution from the clear day best describes the aerosol size distribution since the values are lower. The lognormal distribution best describes the aerosol size distribution on the foggy day (20160508).
KEYWORDS: Atmospheric Aerosols; Size Distributions; Junge; Bimodal; Gamma; Lognormal; Particle Swarm Optimization; Inverse Problem; Aerosol Optical Depth
Strategies for Making Best Offers on eBay
Authors: Britt William , Gryc William , Oliva Jamie , Tuff Brittney , White Charli
Published: May 2019

We model for “Buy-It-Now or Best Offer” auctions on eBay using two different models. In the first model, risk-neutral bidders submit bids in serial and try to surpass a stochastic seller threshold while taking into account how many previous failed bids were made by other bidders. We compute optimal strategies for this model and show that bidder expected surplus decreases in the number of previous failed bids. In the second model we assume bidders do not know how many previous failed bids have been made, and instead use a first-price sealed-bid mechanism with a buy-out price where bidders serially submit bids with the knowledge that no previous bidders have used the buy-out price. We derive a unique equilibrium bidding strategy for risk-neutral bidders in this serial model, show that any equilibrium in a similar parallel bidding model is the same as the equilibrium in the serial model, and compute seller revenue. In particular, under certain circumstances, bidders will bid more in this format than they would in a standard first-price sealed-bid auction, but that a seller maximizes expected revenue by setting a buy-out price higher than any bidder is willing to pay thereby making the auction essentially a first-price auction.
KEYWORDS: Auction Theory; eBay; Buy-It-Now or Best Offer; Symmetric Bayesian Nash Equilibrium; Buy-Out Price; First-Price Sealed-Bid
The Relationship Between Parenting Styles and Substance Use Among University Students
Authors: Niazi Zackaria , Dick Danielle , Adkins Amy , Cooke Megan
Published: May 2019

Parenting styles are important in the behavioral development of adolescents. The environment created by the parent, in regards to communication with their child and level of independence given to their child, may influence the child’s susceptibility to risk behaviors. This study examines the relationship between parenting style and substance use among university students. We hypothesized that university students exposed to lower levels of autonomy granting (AG) or parental involvement (PI) parenting styles would have an increased likelihood of alcohol and nicotine use. We also hypothesized that religiosity, parental education level, ethnicity, and gender would act as moderators of parenting styles and alcohol and nicotine use. Data from a diverse university-wide sample was collected in the fall semester of the student’s freshman year from 2011-2014 (N = 9889, 61.5% female). Results demonstrated that AG had a significant, negative association with alcohol use (B = -0.033, p = 0.006) and nicotine use (B = -0.066, p <0.001). All moderators were found to be significant predictors of alcohol use, however only father education level demonstrated a borderline significant moderation of the relationship between PI and alcohol use. Religiosity, Black race, Asian race, and gender were found to be significant predictors of nicotine use. Only gender moderated the association between PI and nicotine use. Even though alcohol and nicotine use and AG were associated, our results indicate that once students enter university, previous parenting style does not have a strong effect on alcohol and nicotine use behaviors in our sample.
KEYWORDS: Parenting Styles; University Students; Risky Behaviors; Autonomy Granting; Parental Involvement; Alcohol; Nicotine; Drug; Behavioral Biology; Substance Use
Thermodynamics of Concanavalin A Self-Association in the Presence of Osmolytes
Authors: Pfister Tyler , Cooper Shamus , Myers Jeffrey
Published: May 2019

Protein-protein interactions are critical for biological function and depend significantly on environmental factors. A wide variety of small organic molecules that comprise the cellular environment are capable of interacting with proteins to affect folding, binding, and association. The plant lectin concanavalin A (ConA) undergoes a reversible, pH dependent dimer-to-tetramer equilibrium and has been used in our laboratory as a model system to study the effect of osmolytes on protein self-association. Previous research determined that trimethylamine N-oxide (TMAO) stabilizes the tetrameric conformation, while urea favors the dimer. Studying the equilibrium over a range of temperatures allowed quantification of the enthalpy change (∆H) and entropy change (∆S) of tetramer formation. Urea increased both the ∆H and ∆S of tetramer formation, while TMAO decreased both. These effects are consistent with preferential hydration of the dimer-dimer interface in TMAO solution and preferential binding of urea to the interface.
KEYWORDS: Concanavalin A; Osmolytes; Trimethylamine N-oxide; Urea; Protein-Protein Interaction; Equilibrium; Enthalpy; Preferential Hydration
Perception of peer drinking and access to alcohol mediate the effect of residence status on alcohol consumption
Authors: Williams Katrina , Thomas Nathaniel , Adkins Amy , Dick Danielle
Published: May 2019

Alcohol consumption is common in college attending populations and can have a negative impact on an individual's academic, physical, and mental health. Previous research suggests that living at home could act as a protective measure. The current research looks at potential mediators of the association between living with parents while attending college and amount of alcohol consumed. In particular, this study examined access to alcohol, parental involvement, and perception of peer drinking as mediators of the association. This study examined freshman data collected from a survey conducted at a large public university in the mid-Atlantic United States. A pathway model was fit to test the relationships between residence status, access to alcohol, parental involvement, and perception of peer drinking on alcohol consumption. We observed statistically significant indirect effects of residence status on alcohol consumption through the perception of peer drinking and access to alcohol. Parental involvement was significantly related to lower alcohol consumption and there was a direct effect of residence status on alcohol consumption. There were significant indirect effects of residence status on alcohol consumption through both peer drinking and access to alcohol. Parental involvement was associated with decreased alcohol consumption, with no indirect effect in association with residence status. These effects were persistent in the presence of a range of covariates, including age, gender, ethnicity, and parental education.
KEYWORDS: Emerging Adult; Alcohol; Residence Status; Peer Drinking; Access to Alcohol; Parental involvement; Path Analysis
Conduction Mechanism in Electrically Conducting Polymers
Authors: Gochnauer Daniel , Gilani T
Published: May 2019

The conduction mechanism in conducting polymers is reviewed and experimental results of temperature dependence of electrical conductivity of PF6 doped polypyrrole in temperature range of 77 to 300 K are discussed. The room-temperature conductivitywas experimentally determined to be 73 ± 3.4 S/m and temperature dependence follows the Mott’s variable range hopping model. The average hopping distance at 298 K was (6.75 ± 0.97) ×10-8 cm. The coefficient of decay of the localized states, the density states at the Fermi level, and the hopping activation energy were calculated to be (3.5±0.51) ×107 cm-1, (1.92 ± 0.83) ×1022 cm-3 eV-1, and 0.040 ± 0.001 eV respectively.
KEYWORDS: Electrically Conducting Polymers; Doped Polypyrrole; Temperature Dependence of Conductivity; Hopping Activation Energy; Density of State at Fermi level
Determining Nutritional Barriers to Access to Fresh Fruits, Vegetables, and Whole Grains in Older Americans
Authors: Anderson-Morgan Tornia , Fett Melissa , Jasso Michelle , Moten Aisha , Harrison Elgloria
Published: May 2019

The University of the District of Columbia is a partner of the Northeast Hatch Multistate Research Collaborative. This research project, known as the UDC NE 1439, was designed as a pilot study to determine the barriers that prevented the consumption of fresh fruits, vegetables, and whole grains among older adults in Wards 5, 7, and 8 in the District of Columbia (DC). The residents of these wards have been shown to have higher rates of chronic diseases. Data shows that Ward 7 has the highest rate of deaths due to diabetes. Furthermore, Wards 5, 7, and 8 have the highest percentage of hypertension and diabetes This project used a quantitative and qualitative survey instrument, which included 53 questions and/or statements using a Likert scale: demographics (8 questions); household information (2 questions); shopping habits (8 questions); eating habits, including the identity of the person who prepared meals in the home (21 questions); physical fitness (11 questions); and policy (3 questions). Ninety-six (96) older adults participated in the survey, with a gender distribution of 77% female (68 individuals), 22% male (24 individuals), and 1% not reported (1 individual). The racial distribution of the participants was 91% (87) African American, .01% (one) Asian American, .01% (one) Caucasian, .01% (one) Native American, and .03% (three) others/not reported. Additionally, according to the participants’ residency results, Ward 5 accounted for 23% of the participants (24 participants), Ward 7 for 38% (33 participants), and Ward 8 for 38% (33 participants). The participants’ average age was ≥ 56, (45 to 76 and over) and most were the primary financial supporters of their households and the primary grocery shoppers in their families. In conclusion, this project determined that access to fresh fruits and vegetables and travel time to a full-service grocer were less prominent barriers; this was an unexpected finding. Though the participants indicated sufficient access to fresh fruits, vegetables, and whole grains, they lacked nutrition-based knowledge. Many of them viewed unfitting food choices as healthy. An intervention centered on nutrition education using food demonstrations and grocer tours would improve nutrition knowledge in this population. This offered these nutrition and dietetics research assistants with an opportunity to provide nutrition education to the population in question. Moreover, it presents an opportunity to extend nutrition education to all seniors across the Washington, DC region.
KEYWORDS: Fruits; Vegetables; Whole Grains; Urban; Disease; African American; Health; Nutrition; Food Security; Food Desert, Senior Citizens
Characterization of Ambient Particulate Matter Sampled at an Active Sand Mine Facility in Northwestern Wisconsin
Authors: Zhang Julie , Fischer Callie , Oster Joe , de Carvalho Chaves Gabriel , Mooney Rachel , Cleary Patricia
Published: May 2019

Concern has arisen about levels of silica in ambient particles near sand mines in Northwestern Wisconsin. Airborne particles released from mining and processing activity may release respirable silica into the air, which can have adverse health effects on individuals exposed to significant quantities. In order to assess these levels of silica, this study developed a parallel analysis using an X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDS) analysis to test particles in real air samples. Calibrations were constructed for the XRD analysis (following NIOSH Method 7500) with silica standards containing 10 μg – 500 μg respirable silica on filter media with detection limits of 19-28 μg. SEM-EDS methods incorporated identifying the geologic composition of particles using the elemental analysis. Real air samples were collected at a sand mining site using a cascade impactor. Filter substrates were pre-weighed and post-weighed to determine the total dry mass of particles sampled and XRD results show at maximum 16 % of the mass can be attributed to crystalline silica in the samples. An SEM-EDS analysis to categorize the particles geologic classification using ratios of elements shows more than 70% of sampled particles are classified as potassium feldspars.
KEYWORDS: Particulate Matter; Sand Mining; Silica; Atmospheric Characterization; XRD; SEM-EDS; Fugitive Dust
Dextran Sulfate Based Gel Coating for Drug Eluting Balloon Angioplasty
Authors: Mosier Jenna , Stealey Hannah , Stringfield Kalifa , Webb Katie , Simpson LaShan
Published: May 2019

Vascular calcification, a consequence of cardiovascular disease, disrupts natural blood flow and can result in death. Common treatment efforts include various anti-inflammatory medications, balloon angioplasty, or stents, with little success in completely reversing calcification. The proposed design focuses on improving current drug-eluting stents by developing a dextran-sulfate-based gel drug delivery system loaded with receptor activator of nuclear kappa B-ligand (RANKL) to induce osteoclast differentiation. To ensure that the gel could properly deliver RANKL, the gel was tested for its affinity for hydroxyapatite (HA), a critical component of calcification, and its ability to withstand shear. Infrared spectroscopy (IR) indicated binding to HA. Preliminary scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS) results confirmed the presence of calcium on the gel after a one-hour soak in a HA mixture. Shear testing demonstrated that negligible protein, an average of 0.029± 0.024 μg/mL, was sheared off under flow conditions, indicating that the gel is stable for duration of balloon delivery. These preliminary results indicate that a dextran-sulfate-based gel has potential to serve as a therapeutic gel-coating to treat vascular calcification. Future experimentation will include a co-culture study to determine whether osteoclast progenitor cells will properly proliferate and differentiate in the presence of the RANKL-loaded gel.
KEYWORDS: Angioplasty; Calcification; Cardiovascular; Dextran; Gel; Osteoclast; Stent; Vascular
Measuring the Mechanical Properties of Laminated Wood Structures Using a Homemade Bending Tester
Authors: Weber J , Stollenwerk A
Published: May 2019

The choice of materials used to build a laminate recurve bow is crucial to optimizing performance. To this end, a low-cost bending tester was designed and built to measure the flexural modulus and modulus of rupture on a variety of wooden laminates. To gain a better understanding of the relationship between the properties of the laminates and the individual species comprising the laminates, woods with a wide range of elastic and strength properties were chosen. Differences between the expected and experimental results are attributed to the properties of the adhesive and defects in the wood.
KEYWORDS: bending test; recurve bow; wood; laminates; modulus of rupture; flexural modulus