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Introduction: Rift Valley fever virus (RVFV) belonging to the Phenuiviridae family is responsible for a zoonotic disease called Rift Valley fever (RVF). Currently, RVFV has spread from Africa to Asia, and due to its ability to cause high mortality rates, it has significantly impacted human health and economic development in many societies. Highly specific and sensitive systems for sero-diagnosis of RVFV infection are needed for clinical use. Method: BALB/c mice were immunized with recombinant RVFV nucleocapsid (rRVFV-N) protein and the spleen cells fused with SP2/0 myeloma cells to create hybridoma cell lines. The secreted monoclonal antibodies (MAbs) were purified and characterized. Enzyme-linked immunosorbent assay (ELISA) systems for the detection of IgG and IgM using the new MAbs were established and evaluated. Serum samples from 96 volunteers and 93 patients of suspected RVF from Kenya were tested compared with the ELISA systems based on inactivated viruses and the rabbit polyclonal antibody. Result: Three monoclonal antibodies against rRVFV-N protein were established. The performance of the MAb-based sandwich IgG ELISA and the IgM capture ELISA perfectly matched the ELISA systems using the inactivated virus or the polyclonal antibody. Conclusions: Recombinant RVFV-N protein-specific MAbs were developed and they offer useful tools for RVFV studies. The MAb-based ELISA systems for detecting IgG and IgM offer safe and useful options for diagnosing RVFV infections in humans.

Dalia Khalife,1 Ali Khalil,1 Mohamad N Itani,2 Fatin Khalifeh,1 Sara Faour,1 Anastasia Salame,1 Ghina Ghazeeri11Department of Obstetrics & Gynecology, American University of Beirut Medical Center, Beirut, Lebanon; 2Department of Dentistry, American University of Beirut Medical Center, Beirut, LebanonBackground: Periodontal disease can lead to bacteremia with release of cytokines, affecting implantation in women trying to conceive through in vitro fertilization (IVF). A potential association between maternal periodontal disease and poor IVF outcomes has been described.Objective: The aim of the study is to assess whether pre-existing periodontal disease has any effect on IVF parameters.Method: A pilot study composed of 34 women was conducted at a tertiary care center. Prior to IVF, dental examination, IVF parameters were collected.Results: Thirty-four women participated in the study. The outcomes of 28 women (82.3%) were analyzed. Out of the 28 patients, 17 patients had a positive pregnancy test (60.7%) with a total of 13 live births (46.4%) and 4 pregnancy losses (14.3%). Plaque and bleeding index scores were both lower in patients who achieved pregnancy after IVF yet did not reach statistical significance (p=0.309 and 0.422). Comparison of mean values for the different infertility parameters showed no significant differences among women with different IVF outcomes (p>0.05). Different degrees of inflammation of the gingiva did not have an effect on the different clinical parameters and the live birth rates.Conclusion: The evidence provided by the present study does not support the hypothesis. Addressing the status of oral health before any infertility treatment remains to be elucidated.Keywords: periodontal disease, in vitro fertilization, infertility, inflammation, live birth

Abstract Background Rift Valley Fever (RVF) is a mosquito-borne viral zoonosis. To detect RVF virus (RVFV) infection, indirect immunoglobulin G (IgG) and immunoglobulin M (IgM) enzyme linked immunosorbent assays (ELISAs) which utilize recombinant RVFV nucleocapsid (RVFV-N) protein as assay antigen, have reportedly been used, however, there is still a need to develop more sensitive and specific methods of detection. Methods RVFV-N protein was expressed in Escherichia coli (E. coli) and purified by histidine-tag based affinity chromatography. This recombinant RVFV-N (rRVFV-N) protein was then used as antigen to develop an IgG sandwich ELISA and IgM capture ELISAs for human sera. Ninety six serum samples collected from healthy volunteers during the RVF surveillance programme in Kenya in 2013, and 93 serum samples collected from RVF-suspected patients during the 2006–2007 RVF outbreak in Kenya were used respectively, to evaluate the newly established rRVFV-N protein-based IgG sandwich ELISA and IgM capture ELISA systems in comparison with the inactivated virus-based ELISA systems. Results rRVFV-N protein-based-IgG sandwich ELISA and IgM capture ELISA for human sera were established. Both the new ELISA systems were in 100% concordance with the inactivated virus-based ELISA systems, with a sensitivity and specificity of 100%. Conclusions Recombinant RVFV-N is a safe and affordable antigen for RVF diagnosis. Our rRVFV-N-based ELISA systems are safe and reliable tools for diagnosis of RVFV infection in humans and especially useful in large-scale epidemiological investigation and for application in developing countries.

Redox titration problems are considered difficult for students to learn due to their abstract nature, the myriad amount of representations, and the mathematical competency required to learn and solve. The goal of this research project is to examine challenges students face in learning about redox titration-related problems, approaches they use in learning about electrochemical titration problems, and reliance on algorithmic problem-solving instead of conceptual understanding in solving these problems. The research project took place at the City College of New York, which is an urban, minority serving, and public institution. The research instrument used in this research investigation is a survey comprised of Likert-type and open-ended questions. The number of research participants is n = 184. The data was collected and analyzed and histograms and figures were made based on the data analysis. A single factor ANOVA method was performed on the Likert-type questions which showed evidence against the null hypothesis and that shows a strong relationship between variables. The data indicate that the principal barrier to learning about redox titration related problems is that students' reliance on algorithmic problems solving, rote learning, and mathematical approaches. Students' dependence on rote learning and memorization in problem solving could be attributed to the lack of well-developed understanding of the concepts. The investigation shows that students focus on surface features in learning and this translates to hindrance of knowledge transfer.

The subject of buffer solutions in chemistry is a challenging concept for students to learn due to its abstract nature. The difficulties that students face in learning about buffer solutions can lead to poor performance and alternative conceptions about the topic. The development of successful conceptual understanding to solve buffer solution problems requires that students have factual knowledge, procedural knowledge, and conceptual knowledge about the topic. This research project of the City College of New York (a minority-serving, public, urban, commuter institution) investigates difficulties that students experience in learning about buffer solutions and approaches that they rely on to solve buffer-related problems. The research method employed a survey comprised of a Likert-type and open-ended questions was used to assess the understanding of 102 participants. The research results indicate that the principal barrier to learning about buffer solutions is students' dependence on formulaic problem solving and calculator use instead of reliance on conceptual understanding. Furthermore, students face difficulties memorizing a significant number of complicated formulas and equations necessary to solving buffer problems. The dominance of student strategies based on plug and chug problem solving likely hinders the development of conceptual understanding. We recommend that instructors need to be familiar with and address difficulties and alternative conceptions students have about buffer solutions.

General Chemistry is a course where students are expected to nurture the development of their fundamental concepts in chemistry. Students begin general chemistry with alternative conceptions about the topics and fragmented knowledge structures. Majority of students who successfully complete the general chemistry course sequence continue to hold onto their alternative conceptions about the topics. The goal of this study is to examine alternative conceptions and their persistence, learning gains, and conceptual change as the result of instruction and completion of a traditional general chemistry course. The Chemistry Concepts Inventory survey was administered as a laboratory activity at the beginning and at the completion of General Chemistry course. The data was collected from 358 participants at a public, urban, and minority serving college and the data was entered into a spreadsheet and analyzed. Our data suggests that normalized learning gains were not substantial after the completion of a general chemistry course taught in the traditional lecture format which may emphasize algorithmic problem-solving and does not address conceptual understanding of the topics. Traditional lecture format in general chemistry falls short of addressing alternative conceptions, causing a conceptual change, and improving conceptual understanding in students. Based on the research, we recommend that General Chemistry teaching and learning strategies need to address alternative conceptions and improve students' conceptual understanding of chemistry key concepts by immersing students in courses where teaching and learning methods are based on research in science education.

Strategic note-taking is beneficial to students in that it provides a certain way a student can learn, and it can help a student perform better in courses. Taking strategic notes is seen as an important skill that is needed in a college setting. Strategic note-taking involves active listening, processing information, and writing. It is hypothesized that a student's strategic and extensive note-taking can yield a higher performance and achievement. Proper note-taking is a skill that many college students lack. The objective of this research study is to examine whether strategic-note taking improves science, engineering, and mathematics students' performance, achievement, and learning. A survey research was done and collected from 160 students of the City College of New York. The survey questionnaire included Likert-type and open-ended questions, which served to understand the students' views, perceptions, and beliefs about the benefits of strategic note-taking. Data collected from this research project show that note-taking improves students' recall of material, increases students' understanding of the content, assists in preparation for examinations, and improves their overall grades. Note-taking plays a role in gaining knowledge, learning and success in courses. Also, it is noteworthy that our data show a correlation between note-taking and grade point average (GPA); students who take better notes have higher GPAs.