Predicting Second Language Proficiency with Resting-state Brain Rhythms

Understanding what traits facilitate second language (L2) learning has been the focus of many psycholinguistic studies for the last thirty years. One source of insight comes from quantitative electroencephalography (qEEG), i.e., electrical brain activity recorded from the scalp. Using qEEG, Prat et al. [1] found that functional brain connectivity is predictive of language learning ability. This study extends Prat et al. in investigating the predictive validity of qEEG measures for two measures of L2 proficiency, namely: 1. a grammaticality judgement task (GJT), wherein participants read and identified Spanish sentences as either correct or incorrect based on possible grammar violations, and 2. a standardized Spanish proficiency test (DELE). Participants were L2 learners recruited from third- and fourth-semester university Spanish classes. Spectral power and coherence within and across six different regions were analyzed for correlations with either GJT or DELE scores. Follow-up linear regression models based on significant qEEG correlates explained up to 11% of variance in DELE scores but none of the variance in GJT scores. Negative correlations were found between theta frequency coherence and the DELE. Because theta activity has been associated with episodic and working memory performance, these findings suggest that less proficient learners might utilize memory-based strategies more often to compensate for their lack of familiarity with the L2.

Columbia Spring Research Symposium 2021

Featured posters from the annual Columbia Spring Research Symposium hosted by CUSJ

Effects of APOBEC3G's Cytidine Deaminase Activity on Retroviral Evolution

Apolipoprotein B editing complex (APOBEC3/A3) genes are found in mammalian cells. In primates, there are 7 APOBEC3 genes, namely, 3A, 3B, 3C, 3DE, 3F, 3G, and 3H. Previous research has shown that A3 proteins help to inhibit viral infection via their cytidine deaminase activity. However, it has also been found that A3 proteins could also lead to viral evolution, where viruses such as HIV (Human Immunodeficiency Virus) instead gain beneficial mutations that enable them to overcome the antiviral activity of A3 proteins, gain resistance to certain drugs used for treating viral infections and escape recognition by the immune system. This paper is a review article summarizing the role of A3G on viral infection and evolution, and the potential impact viral evolution could have in treatment of retroviral infections such as HIV.

Microbiome Composition and Circadian Rhythm Disruption Alters Epithelial Barrier Integrity

The intestine is home to one of the most complex ecological communities, termed the human gut microbiome. The gut microbiome modulates a wide range of human diseases from diabetes to neurological disorders to cancer. Separating the host and the gut microbiome is the epithelial barrier. The intestinal epithelium serves as an adaptive interaction hub between the host and microbiome that plays an important role in deciding the outcome of host-microbiome interactions. Regulation of epithelial barrier permeability to ions, nutrients and microbiome metabolites is known to be a tightly controlled process on the host side. However, whether the microbiome community also affects epithelial permeability remains unclear. Here, we show that alterations in microbiota composition by treatment with antibiotics selectively targeting specific members of the microbiome community impacts the permeability of the intestine. Additionally, modulating the microbiome through other methods such as altering diet composition shows changes in permeability of the epithelial barrier. As daily feeding rhythm entrains diurnal fluctuations in microbiome, we have set out to measure epithelial barrier permeability throw out the clock. We have discovered that the permeability of the intestinal epithelial barrier exhibits circadian rhythms in mice. Disruption of these rhythms, through jet-lag or genetic deficiencies in circadian machinery, consequently alters epithelial barrier integrity. Together, these findings provide evidence that disruptions in circadian rhythms as well as alterations in microbiome composition have direct consequences in intestinal permeability, and that microbiome might serve as a tool in regulating epithelium permeability.

Letter from the President

Letter from the 2020-2021 President, Arya Rao

Identification of LncRNAs as Therapeutic Targets in Chronic Lymphocytic Leukemia

Chronic Lymphocytic Leukemia (CLL) is one kind of blood cancer that has a very heterogeneous biological background, which results in diverse stages of the CLL and complex treatment strategies. However, a small part of the tumor may disappear without receiving any treatment. This condition is known as “spontaneous regression” and occurs as a result of a poorly investigated mechanism. Exposing the underlying causes of this condition can lead to a novel treatment approach for CLL and other types of cancer. While most such mechanisms have been assumed to be directly linked to protein coding genes, a recent approach was aimed to carry out more comprehensive studies by focusing on non-protein coding genes as well as protein-coding genes at the RNA level. In this article, we applied in-silico analysis of total RNA expression data from 24 CLL samples to determine possible regulatory mechanisms of spontaneous regression in CLL. These were selected by comparing spontaneous regression with progressive samples of CLL at the transcriptional level. As a result, 33 lncRNAs were found to be significantly differentially expressed among these conditions based on differential gene expression analysis. Current study suggested lncRNAs, PTPN22-AS1, PCF11-AS1, SYNGAP1-AS1, PRRT3-AS1 and H1FX-AS1 as potential therapeutic targets to trigger spontaneous regression. Eventually, the results presented here reveal new insights into the spontaneous regression and the relation with the non-coding RNAs, particularly lncRNAs.

Letter from the Editor-in-Chief

Letter from the 2020-2021 Editor-in-Chief, Isabella Leite

Effect of Eccentricity in Microwave Imaging of Multiple Composite Pipes

The use of non-metallic composites that are durable, low cost, and lightweight is growing fast in various industries. A commonly used form of these materials is in the shape of pipes that can be used, for instance, in oil and gas industry. Such pipes can be damaged due to material loss (defects and holes), erosions, and more which may cause major production failures or environmental mishaps. To prevent these issues, non-destructive testing (NDT) methods need to be employed for regular inspections of such components. Since traditional NDT methods are mainly used for metallic pipes, recently microwave imaging has been proposed as a promising approach for examination of non-metallic pipes. While microwave imaging can be employed for inspection of multiple layers of pipes, the effect of undesired eccentricity of the pipes can impose additional imaging errors. In this paper, for the first time, we study the effect of eccentricity of the pipes on the images reconstructed using near-field holographic microwave imaging when imaging double pipes.

A Letter from the Editorial Board

Dear readers, After a year of developments, we are proud to present the Spring 2017 Columbia Undergraduate Science Journal. The current edition of the journal features topics from all over the natural sciences. This year, our main focus regarding the Journal was to extend the reach of the journal to universities all over the world. As the CUSJ’s mission is to encourage students to involve themselves in scientific discovery, we saw no need to restrict our scope to only Columbia University. We received submissions from diverse areas such as biochemistry, astrophysics, and electrical engineering. Our team also published the second issue of the Columbia Junior Science Journal, a journal meant to introduce high school researchers to the world of research publication. After making changes to the previous Columbia Research Scholars Journal to better reflect the mission of the journal, we were proud to publish many of the incredible submissions sent in from high schoolers from around the United States, and invite several of them to our annual Spring Symposium. In addition to producing the two research journals for high school and college students, the CUSJ also seeks to foster the undergraduate research community at Columbia University. This year, we worked hard to further this goal by hosting several events on campus. In the Fall, the CUSJ hosted an event to assist undergraduate students in the process of soliciting a research position. In the Spring, the CUSJ hosted Dr. George Yancopoulos, founder of Regeneron and chief scientific officer, and held the annual symposium. This year’s the CUSJ Spring Research Symposium involved a welcome address from Dr. Gasperov, the undergraduate science research adviser at Columbia University, as well as a poster session where students presented on their research. The Awards of Excellence this year went to Nicholas Page from Rutgers University and Sarah Lundell from Fordham University. This Spring, the CUSJ also established the CUSJ Colloquium, a bi-weekly undergraduate speaker series where students from an array of scientific disciplines presented their research in a comfortable peer setting. Students discussed topics in research subjects including two-dimensional materials, exoplanets, biofilms, viral binding, ophthalmology, and photosynthetic origins of life. Our publications, the CUSJ and CJSJ, and the events we hosted this year could not have happened without the hard work of our editorial team and the assistance of our faculty board and advisors. Natalie Kolba, Editor-in-Chief Osman Moneer, President

Anomaly Correction by Optimal Trading Frequency

Under the assumption that security prices follow random walk, we look at price versus different moving averages. Different periods of moving averages give investor different signals and we assume that a rational investor would want to buy more when the price goes down. This paper provides a theoretical model for an investor to systematically buy heavy when the security prices go down.