Research papers

Atmospheric dispersion modeling and radiological safety analysis for a hypothetical accident of Ghana Research Reactor-1 (GHARR-1)

Jérémie Lunguya Muswema, E. O. Darko, J.K. Gbadago, Emmanuel Boafo

Unusual defect physics in CH3NH3PbI3 perovskite solar cell absorber

Wan‐Jian Yin, Tingting Shi, Yanfa Yan

Thin-film solar cells based on Methylammonium triiodideplumbate (CH3NH3PbI3) halide perovskites have recently shown remarkable performance. First-principle calculations show that CH3NH3PbI3 has unusual defect physics: (i) Different from common p-type thin-film solar cell absorbers, it exhibits flexible conductivity from good p-type, intrinsic to good n-type depending on the growth conditions; (ii) Dominant intrinsic defects create only shallow levels, which partially explain the long electron-hole diffusion length and high open-circuit voltage in solar cell. The unusual defect properties can be attributed to the strong Pb lone-pair s orbital and I p orbital antibonding coupling and the high ionicity of CH3NH3PbI3.

Cohesion in English

Μ. Α. Κ. Halliday, Ruqaiya Hasan

Cohesion in English is concerned with a relatively neglected part of the linguistic system: its resources for text construction, the range of meanings that are speciffically associated with relating what is being spoken or written to its semantic environment. A principal component of these resources is 'cohesion'. This book studies the cohesion that arises from semantic relations between sentences. Reference from one to the other, repetition of word meanings, the conjunctive force of but, so, then and the like are considered. Further, it describes a method for analysing and coding sentences, which is applied to specimen texts.

Learning Phrase Representations using RNN Encoder–Decoder for Statistical Machine Translation

Kyunghyun Cho, Bart van Merriënboer, Çağlar Gülçehre, Dzmitry Bahdanau, Fethi Bougares, Holger Schwenk, Yoshua Bengio

Kyunghyun Cho, Bart van Merriënboer, Caglar Gulcehre, Dzmitry Bahdanau, Fethi Bougares, Holger Schwenk, Yoshua Bengio. Proceedings of the 2014 Conference on Empirical Methods in Natural Language Processing (EMNLP). 2014.

Glove: Global Vectors for Word Representation

Jeffrey Pennington, Richard Socher, Christopher D. Manning

Recent methods for learning vector space representations of words have succeeded in capturing fine-grained semantic and syntactic regularities using vector arith-metic, but the origin of these regularities has remained opaque. We analyze and make explicit the model properties needed for such regularities to emerge in word vectors. The result is a new global log-bilinear regression model that combines the advantages of the two major model families in the literature: global matrix factorization and local context window methods. Our model efficiently leverages statistical information by training only on the nonzero elements in a word-word co-occurrence matrix, rather than on the en-tire sparse matrix or on individual context windows in a large corpus. The model pro-duces a vector space with meaningful sub-structure, as evidenced by its performance of 75 % on a recent word analogy task. It also outperforms related models on simi-larity tasks and named entity recognition. 1

Microsoft COCO: Common Objects in Context

Tsung-Yi Lin, Michael Maire, Serge Belongie, James Hays, Pietro Perona, Deva Ramanan, Piotr Dollár, C. Lawrence Zitnick

Rainfall Variability over Ghana: Model versus Rain Gauge Observation

Francis Nkrumah, Nana Ama Browne Klutse, David Cudjoe Adukpo, Kwadwo Owusu, Kwesi Akumenyi Quagraine, Alfred Owusu, William …

This paper used the International Centre for Theoretical Physics (ICTP) Regional Climate Model, Version 3 (RegCM3) and rain gauge data selected from the Ghana Meteorological Agency (GMet) from 1990 to 2008 to investigate the extent and nature of variability in the annual rainfall and pattern of the raining seasons in Ghana. In the study, six meteorological stations selected from three rainfall distribution zones according to the divisions of the GMet were used to study the pattern of rainfall and its departure from the normal trend. The study also assessed the performance of the RegCM3 simulation with reference to the observed gauge data. Results confirmed the unimodal nature of the rainfall annual cycle over the northern belt and bi-modal rainfall nature over the middle and southern belts of Ghana. Negative departures of rainfall implying consistent downward trend were observed at all the stations. Our analysis showed that RegCM3 captured the average rainfall over Ghana but demonstrated an underestimation as compared to the observed gauge data. The model also had difficulty stimulating the departures accurately in direction and in magnitude in all the stations except for Accra where RegCM3 simulated the right direction of the departures.

Journal of Physics: Conference Series

Pavlova, Petya, Borisova, Ekaterina, Pavlova, Elmira, Avramov, Latchezar

Conservation and restoration of cultural heritage and protection of abandoned buildings is possible using new technologies in order to create a knowledge base to maintain the original condition of buildings as long as possible. This paper presents the digital geometric survey, combining photogrammetry and photogrammetry with drone for the documentation of a building located in the Riviera Romagnola. The fundamental task to survey historic buildings, in order to document their geometric and morphological features with very high accuracy, becomes an important incentive for the use of innovative hybrid approach. The building case study is the Woodpecker nightclub built in 1966 and abandoned in 1970 due to a fire that devastated the structure.

Review: Improving our knowledge of male mosquito biology in relation to genetic control programmes

Rosemary Susan Lees, Bart GJ Knols, Romeo Bellini, Mark Q. Benedict, Ambicadutt Bheecarry, Hervé Bossin, Dave D. Chadee, J. …

An investigation into senior high school (shs3) physics students understanding of data processing of length and time of scientific measurement in the Volta region of Ghana

Eliot Kosi Kumassah, Joseph Ghartey Ampiah, Eugene Johnson Adjei

Serious doubt have been raised in the Physics Chief Examiner's report of the West African Examination Council of Ghana of both physics-1 (theory) and physics-2 (practical) as to whether science students really understand measurement of physical quantities. In view of this, the researcher use a mixed designed method to gather data from SHS3 physics students' on their understanding of data processing of length and time. A population of 422 SHS3 physics students were sampled and a three item questionnaire on distance and time administered in order to find out whether the problem enumerated by the Chief Examiners' of Physics concerning physics students exist and were either with the set paradigm or the point paradigm concept. Also twenty SHS3 physics were purposively selected and interviewed in order to validate students' written responses. The study revealed that students do not have an understanding of using repeat in data set, anomaly in data set and straight line graph of data by the set paradigm concept i.e. all the three items on data processing of students (i.e. UR, AN, and SLG) were in line with the point paradigm concept of measurement. Also students seemed to have difficulty in plotting straight line graph by the use of lines of best fit.

Genome engineering using the CRISPR-Cas9 system

F. Ann Ran, Patrick D. Hsu, Jason Wright, Vineeta Agarwala, David Scott, Feng Zhang

MEGA6: Molecular Evolutionary Genetics Analysis Version 6.0

Koichiro Tamura, Glen Stecher, Daniel S. Peterson, Alan Filipski, Sudhir Kumar

The Molecular Evolutionary Genetics Analysis (MEGA) software has matured to contain a large collection of methods and tools of computational molecular evolution. Here, we describe new additions that make MEGA a more comprehensive tool for building timetrees of species, pathogens, and gene families using rapid relaxed-clock methods. Methods for estimating divergence times and confidence intervals are implemented to use probability densities for calibration constraints for node-dating and sequence sampling dates for tip-dating analyses. They are supported by new options for tagging sequences with spatiotemporal sampling information, an expanded interactive Node Calibrations Editor, and an extended Tree Explorer to display timetrees. Also added is a Bayesian method for estimating neutral evolutionary probabilities of alleles in a species using multispecies sequence alignments and a machine learning method to test for the autocorrelation of evolutionary rates in phylogenies. The computer memory requirements for the maximum likelihood analysis are reduced significantly through reprogramming, and the graphical user interface has been made more responsive and interactive for very big data sets. These enhancements will improve the user experience, quality of results, and the pace of biological discovery. Natively compiled graphical user interface and command-line versions of MEGA11 are available for Microsoft Windows, Linux, and macOS from www.megasoftware.net.

Modelling and Assessing Experimental Competencies in Physics

Heike Theyßen, Horst Schecker, Christoph Gut, Martin Hopf, Jochen Kühn, Peter Labudde, Andréas Müller, Nico Schreiber, Patri…

Nursing informatics: A key to improving nursing practice in Nigeria

O J Daniel

  Nursing informatics is a new nursing specialty in Nigeria; even though it was approved by the American Nurses Association in 1992 as a recognized specialty and has since been growing. The building blocks of this specialty are nursing, information and computer sciences. These three combined provide the knowledge base of nursing informatics. Expanded roles and technology are being incorporated into the domain of nursing informatics. The effects of these roles are visible across all sectors of nursing. This paper explores the field of nursing informatics and presents the relevance to contemporary nursing. Nursing leaders in all areas including research, education and administration and the Nursing and Midwifery Council of Nigeria have a big role to play in ensuring that nursing informatics is embraced by all nurses in Nigeria.   Key words: Nursing informatics, contemporary nursing practice, competencies, Nigeria.

Innovative Strategies for Teaching Nursing Research in Taiwan

Shwu‐Ru Liou, Ching‐Yu Cheng, Hsiu‐Min Tsai, Chia‐Hao Chang

BACKGROUND: Evidence-based practice is imperative in clinical settings because it bridges the gap between research findings and clinical practice. Promoting nursing student interest and enthusiasm for research is therefore crucial when teaching nursing research. OBJECTIVE: The aim of thus study was to develop innovative teaching strategies that increase nursing students' interests and engagement in research. METHODS: This study employed a descriptive, pretest-posttest, quasiexperimental design with 103 participants in the experimental group and 106 in the control group. The Attitudes toward Research Questionnaire, Classroom Engagement Scale, Self-Directed Learning Instrument, Nursing Eight Core Competencies Scale, Value of Teams survey, and a research knowledge test were applied to evaluate the outcomes of the innovative teaching strategies. RESULTS: Scores for the research knowledge test were significantly higher in the experimental group than in the control group in posttest 1 and posttest 2. After the intervention, participants in the experimental group exhibited higher scores on attitudes toward research, eight core competencies in nursing,value of teams, classroom engagement, and self-directed learning than participants in the control group. Students in the experimental group perceived a lower degree of pressure and higher degrees of interest, enjoyment, and acceptance of the research course than students in the control group. CONCLUSIONS: This study confirmed that using innovative teaching strategies in nursing research courses enhances student interest and enthusiasm about evidence-based practice.

The Chemistry and Applications of Metal-Organic Frameworks

Hiroyasu Furukawa, Kyle E. Cordova, M. O’Keeffe, Omar M. Yaghi

Background Metal-organic frameworks (MOFs) are made by linking inorganic and organic units by strong bonds (reticular synthesis). The flexibility with which the constituents’ geometry, size, and functionality can be varied has led to more than 20,000 different MOFs being reported and studied within the past decade. The organic units are ditopic or polytopic organic carboxylates (and other similar negatively charged molecules), which, when linked to metal-containing units, yield architecturally robust crystalline MOF structures with a typical porosity of greater than 50% of the MOF crystal volume. The surface area values of such MOFs typically range from 1000 to 10,000 m 2 /g, thus exceeding those of traditional porous materials such as zeolites and carbons. To date, MOFs with permanent porosity are more extensive in their variety and multiplicity than any other class of porous materials. These aspects have made MOFs ideal candidates for storage of fuels (hydrogen and methane), capture of carbon dioxide, and catalysis applications, to mention a few. Advances The ability to vary the size and nature of MOF structures without changing their underlying topology gave rise to the isoreticular principle and its application in making MOFs with the largest pore aperture (98 Å) and lowest density (0.13 g/cm 3 ). This has allowed for the selective inclusion of large molecules (e.g., vitamin B 12 ) and proteins (e.g., green fluorescent protein) and the exploitation of the pores as reaction vessels. Along these lines, the thermal and chemical stability of many MOFs has made them amenable to postsynthetic covalent organic and metal-complex functionalization. These capabilities enable substantial enhancement of gas storage in MOFs and have led to their extensive study in the catalysis of organic reactions, activation of small molecules (hydrogen, methane, and water), gas separation, biomedical imaging, and proton, electron, and ion conduction. At present, methods are being developed for making nanocrystals and supercrystals of MOFs for their incorporation into devices. Outlook The precise control over the assembly of MOFs is expected to propel this field further into new realms of synthetic chemistry in which far more sophisticated materials may be accessed. For example, materials can be envisaged as having (i) compartments linked together to operate separately, yet function synergistically; (ii) dexterity to carry out parallel operations; (iii) ability to count, sort, and code information; and (iv) capability of dynamics with high fidelity. Efforts in this direction are already being undertaken through the introduction of a large number of different functional groups within the pores of MOFs. This yields multivariate frameworks in which the varying arrangement of functionalities gives rise to materials that offer a synergistic combination of properties. Future work will involve the assembly of chemical structures from many different types of building unit, such that the structures’ function is dictated by the heterogeneity of the specific arrangement of their constituents.

Barriers to mental health treatment: results from the WHO World Mental Health surveys

Laura Helena Andrade, Jordi Alonso, Zeina Mneimneh, J. Elisabeth Wells, A. Al-Hamzawi, Guilherme Borges, Evelyn J. Bromet, R…

BACKGROUND: To examine barriers to initiation and continuation of mental health treatment among individuals with common mental disorders. METHOD: Data were from the World Health Organization (WHO) World Mental Health (WMH) surveys. Representative household samples were interviewed face to face in 24 countries. Reasons to initiate and continue treatment were examined in a subsample (n = 63,678) and analyzed at different levels of clinical severity. RESULTS: Among those with a DSM-IV disorder in the past 12 months, low perceived need was the most common reason for not initiating treatment and more common among moderate and mild than severe cases. Women and younger people with disorders were more likely to recognize a need for treatment. A desire to handle the problem on one's own was the most common barrier among respondents with a disorder who perceived a need for treatment (63.8%). Attitudinal barriers were much more important than structural barriers to both initiating and continuing treatment. However, attitudinal barriers dominated for mild-moderate cases and structural barriers for severe cases. Perceived ineffectiveness of treatment was the most commonly reported reason for treatment drop-out (39.3%), followed by negative experiences with treatment providers (26.9% of respondents with severe disorders). CONCLUSIONS: Low perceived need and attitudinal barriers are the major barriers to seeking and staying in treatment among individuals with common mental disorders worldwide. Apart from targeting structural barriers, mainly in countries with poor resources, increasing population mental health literacy is an important endeavor worldwide.

Influence of Family Background on Academic Achievement of Secondary School Biology Students in Anambra State

Abigail M. Osuafor, Ifeoma Okonkwo

The study sought to find out how family background of students in Anambra State, Nigeria influences their academic achievement in senior secondary school Biology. A survey design was adopted for the study. Five hundred and forty-six (546) Senior Secondary Two (SS2) biology students were drawn by simple random sampling from 14 schools within Awka, Nnewi and Onitsha Education Zones, in Anambra State. Three research questions and four hypotheses guided the study. Data were collected using a researcher constructed questionnaire and students‟ SS1 and SS2 school results. The results revealed that family structure, parents‟ occupation and educational level of parents, did not have significant influence on students‟ achievement in biology. Based on the findings, the paper concludes that family background did not have much influence on students‟ achievement in science (biology) as against what most previous studies portrayed. Researches should therefore focus on other possible factors that contribute to students‟ poor performance in Biology and science generally in order to find lasting solution to the problem. Some recommendations were also made.Keywords: Biology, polygamous, monogamous, occupation, educational level, academic achievement.

Context Effects in Processing of Chinese Academic Words: An Eye-Tracking Investigation

Yu‐Cin Jian, Ming-Lei Chen, Hwa‐Wei Ko

This study investigated context effects of online processing of Chinese academic words during text reading. Undergraduate participants were asked to read Chinese texts that were familiar or unfamiliar (containing physics terminology) to them. Physics texts were selected first, and then we replaced the physics terminology with familiar words; other common words remained the same in both text versions. Our results indicate that readers experienced longer rereading times and total fixation durations for the same common words in the physics texts than for the corresponding texts. Shorter gaze durations were observed for the replaced words than the physics terminology; however, the duration of participants' first fixations on these two word types did not differ from each other. Furthermore, although the participants performed similar reading paths after encountering the target words of the physics terminology and replaced words, their processing duration of the current sentences was very different. They reread the physics terminology more times and spent more reading time on the current sentences containing the physics terminology, searching for more information to aid comprehension. This study showed that adult readers seemed to successfully access each Chinese character's meaning but initially failed to access the meaning of the physics terminology. This could be attributable to the nature of the formation of Chinese words; however, the use of contextual information to comprehend unfamiliar words is a universal phenomenon.

Nurses’ attitude towards the care of the elderly: Implications for gerontological nursing training

Modupe Olusola Oyetunde, Olufisayo O. Ojo, Lucia Yetunde Ojewale

Background: Nurses are in contact with the elderly at different levels of care. However, observations show that relational gaps exist resulting in negative elderly patients’ outcomes. This study aimed at exploring the attitude of nurses towards the care of the elderly in two selected hospitals (University College Hospital and Ring Road State hospital) in Ibadan, Oyo state. Methods: The study was a descriptive survey. Questionnaire was administered to randomly selected and consented 130 nurses in the two selected hospitals and was retrieved immediately after being completed. The questionnaires had five sections. Section A covered socio-demographic data. Section B, C and D consisted of questions which explored respondents’ attitude towards the care of elderly; staffing ratio and care of the elderly; factors influencing care of the elderly and Section E questions were on knowledge of aging process. The completed questionnaire was coded and analyzed using frequencies and percentages Result: This study shows that 73.0% of the respondents agreed that elderly are difficult to care for. Over 80% agreed that effective care of the elderly requires special training. Also, more than 90% believed hospitals should have special wards (geriatric ward) for effective care of the elderly. Respondents showed positive attitude towards the care of the elderly and good knowledge of aging process. Conclusion: Effective care of the elderly requires special training, provision of geriatric ward, adequate staffing to reduce stress and improve quality care. There is need for continuing education on quality care to improve nursing practice in the care of the elderly.

Essentials of Nursing Research: Appraising Evidence for Nursing Practice

Denise F. Polit, Cheryl Tatano Beck

Essentials of Nursing Research is designed to teach students how to read, understand, analyze, and evaluate research reports in nursing practice. The Seventh Edition has been updated with stronger coverage of evidence-based practice, including content on how to read, interpret, and critique systematic reviews, which are considered by many to be a cornerstone of evidence-based practice. Also included in the Seventh Edition: a more balanced presentation of medical and social science methods and nomenclature; enhanced coverage of qualitative research; and more!

Introduction: Progress in Meson Theory in Japan

T. Sin-itiro

Tomonaga Sin-itiro; Introduction: Progress in Meson Theory in Japan, Progress of Theoretical Physics Supplement, Volume 1, 1 January 1955, Pages 1–6, https://do

Effect of Zeta Potential on the Properties of Nano-Drug Delivery Systems - A Review (Part 2)

S Honary, F Zahir

The zeta potential (ZP) of colloidal systems and nano-medicines, as well as their particle size exert a major effect on the various properties of nano-drug delivery systems. Not only the stability of dosage forms and their release rate are affected but also their circulation in the blood stream and absorptioninto body membranes are dramatically altered by ZP. In this paper the effect of ZP on the various properties of nano-medicines are reviewed. Furthermore, the ability of employing zeta potential to target drug delivery systems to, and drug release at specific sites of the body are discussed.Keywords: Nano-medicines, Zeta potential, Drug targeting, Site-specific release, Dosage form stability

Introduction to Mediation, Moderation, and Conditional Process Analysis: A Regression-Based Approach

Andrew F. Hayes

I. FUNDAMENTAL CONCEPTS 1. Introduction 1.1. A Scientist in Training 1.2. Questions of Whether, If, How, and When 1.3. Conditional Process Analysis 1.4. Correlation, Causality, and Statistical Modeling 1.5. Statistical Software 1.6. Overview of this Book 1.7. Chapter Summary 2. Simple Linear Regression 2.1. Correlation and Prediction 2.2. The Simple Linear Regression Equation 2.3. Statistical Inference 2.4. Assumptions for Interpretation and Statistical Inference 2.5. Chapter Summary 3. Multiple Linear Regression 3.1. The Multiple Linear Regression Equation 3.2. Partial Association and Statistical Control 3.3. Statistical Inference in Multiple Regression 3.4. Statistical and Conceptual Diagrams 3.5. Chapter Summary II. MEDIATION ANALYSIS 4. The Simple Mediation Model 4.1. The Simple Mediation Model 4.2. Estimation of the Direct, Indirect, and Total Effects of X 4.3. Example with Dichotomous X: The Influence of Presumed Media Influence 4.4. Statistical Inference 4.5. An Example with Continuous X: Economic Stress among Small Business Owners 4.6. Chapter Summary 5. Multiple Mediator Models 5.1. The Parallel Multiple Mediator Model 5.2. Example Using the Presumed Media Influence Study 5.3. Statistical Inference 5.4. The Serial Multiple Mediator Model 5.5. Complementarity and Competition among Mediators 5.6. OLS Regression versus Structural Equation Modeling 5.7. Chapter Summary III. MODERATION ANALYSIS 6. Miscellaneous Topics in Mediation Analysis 6.1. What About Baron and Kenny? 6.2. Confounding and Causal Order 6.3. Effect Size 6.4. Multiple Xs or Ys: Analyze Separately or Simultaneously? 6.5. Reporting a Mediation Analysis 6.6. Chapter Summary 7. Fundamentals of Moderation Analysis 7.1. Conditional and Unconditional Effects 7.2. An Example: Sex Discrimination in the Workplace 7.3. Visualizing Moderation 7.4. Probing an Interaction 7.5. Chapter Summary 8. Extending Moderation Analysis Principles 8.1. Moderation Involving a Dichotomous Moderator 8.2. Interaction between Two Quantitative Variables 8.3. Hierarchical versus Simultaneous Variable Entry 8.4. The Equivalence between Moderated Regression Analysis and a 2 x 2 Factorial Analysis of Variance 8.5. Chapter Summary 9. Miscellaneous Topics in Moderation Analysis 9.1. Truths and Myths about Mean Centering 9.2. The Estimation and Interpretation of Standardized Regression Coefficients in a Moderation Analysis 9.3. Artificial Categorization and Subgroups Analysis 9.4. More Than One Moderator 9.5. Reporting a Moderation Analysis 9.6. Chapter Summary IV. CONDITIONAL PROCESS ANALYSIS 10. Conditional Process Analysis 10.1. Examples of Conditional Process Models in the Literature 10.2. Conditional Direct and Indirect Effects 10.3. Example: Hiding Your Feelings from Your Work Team 10.4. Statistical Inference 10.5. Conditional Process Analysis in PROCESS 10.6. Chapter Summary 11. Further Examples of Conditional Process Analysis 11.1. Revisiting the Sexual Discrimination Study 11.2. Moderation of the Direct and Indirect Effects in a Conditional Process Model 11.3. Visualizing the Direct and Indirect Effects 11.4. Mediated Moderation 11.5. Chapter Summary 12. Miscellaneous Topics in Conditional Process Analysis 12.1. A Strategy for Approaching Your Analysis 12.2. Can a Variable Simultaneously Mediate and Moderate Another Variable's Effect? 12.3. Comparing Conditional Indirect Effects and a Formal Test of Moderated Mediation 12.4. The Pitfalls of Subgroups Analysis 12.5. Writing about Conditional Process Modeling 12.6. Chapter Summary Appendix A. Using PROCESS Appendix B. Monte Carlo Confidence Intervals in SPSS and SAS