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Pressure induced GABAergic neuron damage in C. elegans
Full text linkMild traumatic brain injury (mTBI), particularly from repetitive sublethal blasts, is linked to progressive neurodegeneration and cognitive decline. GABAergic neurons are especially susceptible, yet mechanistic insights remain limited in mammalian models. Caenorhabditis elegans, with its conserved neuroanatomy and genetic tractability, enables high-resolution analysis of neural damage. This study uses a GFP reporter strain to visualize GABAergic damage post-blast, establishing a scalable model for mTBI pathophysiology
Microtubule Instability Drives Developmental Defects in a Tauopathy Model
Full text linkTauV337M is a disease-linked allele that induces protein aggregation and causes degeneration in the worm motor cord 1,2. Loss of rpm-1 in TauV337M ameliorates neurodegeneration
Entropy-Guided Transformers for Sentiment Prediction
Full text linkThe use of an entropy-based loss function to improve BERT’s sentiment analysis on the Stanford Sentiment Treebank (SST-2) dataset. By studying entropy trends in a fine-tuned BERT model, we crafted a custom loss that stabilizes entropy in early layers (1–9) and penalizes entropy rises in later layers (10–12) using a mean entropy threshold. Our approach achieved 92.09% accuracy and a 92.31% F1 score, surpassing a cross-entropy baseline by 1.95%. These results highlight entropy-guided optimization’s potential for transformer models
Investigating Sea Breeze Climatology In Tampa, Florida Using Reanalysis Data
Full text linkTampa is a coastal city situated in the western central peninsula of Florida, this investigation is centered around Tampa International Airport (TPA) at coordinates 27.9 ͦN and 82.5 ͦW, with elevations ranging from 2 to 8 meters above sea level along the coast of Tampa Bay, gradually increasing inland. •El Niño and La Niña: Planetary climate patterns that influence the sea breeze. •Sea breeze: it is formed due to the temperature differences between the air over land and the ocean. •The goal was to investigate sea breeze climatology with the use of reanalysis data
N.A.U.T.I.L.U.S.: Natural Aquaculture Using Technology In Living Underwater Systems
Full text linkMarine protected areas (MPAs) are small subsets of marine ecosystems with limited to no access to exploitation to promote sustainability and growth of healthy populations of marine organisms
Bug brains: Are discoid cockroach (Blaberus discoidalis) substrate preferences fixed or plastic?
Full text linkWith over 4,500 species, cockroaches are one of the most widespread animal groups, thriving in diverse environments across nearly every continent. Despite their abundance, relatively little is known about their behavior and cognitive abilities. Blaberus discoidalis is a burrowing species found in substrates like decaying logs, and leaf litter, making it a valuable model for investigating habitat choice through substrate preferences. Here, we explored whether these preferences are fixed or influenced by rearing history by raising cockroaches in pine bedding (commonly used in animal care), coconut fiber (recommended for burrowing), or without a burrowing substrate (direct from a breeder). We also examined how testing environment (arena vs. T-maze) might shape behavior
Early Breast Cancer Detection with Ultrasound Data using NMF
No full textEarly detection of breast cancer significantly influences patient outcomes. Dynamic Contrast-Enhanced Ultrasound (DCE-US) has shown promise in early detection by visualizing tumor vascularity and perfusion dynamics in real-time. This study evaluates the efficacy of DCE-US in distinguishing four stages of cancer progression: normal, hyperplasia, ductal carcinoma in situ (DCIS), and invasive cancer, using a transgenic mouse model that mimics human breast cancer. Ultrasound burst pulses, while commonly used to remove unbound contrast agents, can potentially damage human tissues. Using the pre-pulse data helps mitigate this risk, ensuring safer and more reliable measurements. A VEGFR2-targeted microbubble contrast agent was injected, and the analysis was conducted using Non-negative Matrix Factorization (NMF), focusing on pre-pulse data. Our results revealed significant p-values that statistically distinguished all combinations of cancer stages except for normal versus hyperplasia and DCIS versus invasive cancer. Additionally, by considering normal and hyperplasia as benign, and DCIS and invasive as malignant, we applied a non-parametric regression model to define a threshold differentiating benign from malignant tissues, achieving robust specificity and sensitivity metrics. These findings underscore the potential of NMF-enhanced DCE-US for accurate tumor characterization and early breast cancer detection, all the while avoiding the use of harmful ultrasound burst pulses to remove unbound tracers. This approach holds significant promise for clinical application
Nonlocal Boundary Value Problems for Linear Hyperbolic Systems
No full textBoundary value problems in a characteristic rectangle Ω = [0, ω1]×[0, ω2] for second order linear hyperbolic systems are considered.
For initial–boundary value problems there are established:
(i) Necessary and sufficient conditions of well–posedness;
(ii) Necessary conditions of solvability;
(iii) Effective sufficient conditions of solvability of two–point initial–boundary value problems;
(iv) Effective sufficient conditions of solvability of initial–periodic problems;
(v) Necessary and sufficient conditions of solvability of ill–posed initial–boundary value problems;
(vi) Necessary and sufficient conditions of solvability of ill–posed initial–periodic problems.
For nonlocal boundary value problems there are established:
(i) Necessary and sufficient conditions of well–posedness;
(ii) Necessary conditions of solvability;
(iii) Effective sufficient conditions of solvability of problems with Nicoletti type boundary conditions;
(iv) Effective sufficient conditions of solvability of problems with boundary conditions of periodic type ;
(iv) Effective sufficient conditions of solvability of doubly–periodic problems;
(v) Necessary and sufficient conditions of solvability of ill–posed doubly–periodic problems
Trends in and Factors Associated with Science Achievement among Fourth Graders in Saudi Arabia: A Secondary Analysis of TIMSS Data
No full textThis secondary analysis examined trends and factors associated with science achievement among fourth-grade students in Saudi Arabia using data from the Trends in International Mathematics and Science Study (TIMSS). Between 2007 and 2019, Saudi students consistently scored below the international average in science, with female students outperforming males by more than 30 points. The study addressed two issues: (1) reasons behind Saudi students’ underperformance and (2) limited research on contributing factors. TIMSS data from 2011, 2015, and 2019 were analyzed using descriptive, correlational, and regression methods. While trends across the years were explored, only 2019 data were used for detailed regression analyses. Science achievement was the dependent variable, with 30 independent variables drawn from student, teacher, school, and home questionnaires. Data were cleaned and prepared through item and scale scoring, outlier detection, and multicollinearity checks. Findings showed that student variables contributed most to science achievement. Peer interactions, science confidence, and home study supports were consistently strong predictors. Teacher and school variables, such as emphasis on iv science investigation and socioeconomic composition, added modest explanatory power. Home background factors, including pre-primary education and parental occupation, also played a meaningful role. Gender-based analyses revealed differences: for males, science confidence and early education were key, while for females, school socioeconomic context and home supports had stronger effects. Study delimitations and limitations, as well as generalizability and implications were discussed. In addition to offering recommendations for further research, the findings support targeted policies that enhance early learning, peer engagement, and equitable learning environments
Trends in and Factors Associated with Science Achievement Among Eighth Graders in Saudi Arabia: A Secondary Analysis of TIMSS Data
No full textThis secondary analysis examined trends in and factors influencing science achievement among eighth-grade students in Saudi Arabia, using data from the Trends in International Mathematics and Science Study (TIMSS). However, Saudi Arabia\u27s performance on the TIMSS science assessments fell below the international average, from 2003 through 2019. In addition, gender differences in science achievement have been observed, with female students outperforming male students by 30 or more points. This study addresses two problems: factors associated with the lower performance of Saudi students on TIMSS science assessments compared to global standards, and the small number of studies which explored factors which may have influenced those results. This study used TIMSS data from 2011, 2015, and 2019. Descriptive and statistical methods, including correlation and regression analysis, were used to explore relationships between various student, teacher, and school-level factors and science achievement. The sample in each annual data set began with more than 6,000 students per year, although the sample size in each analysis varied due to iii missing data. In specific, data from the 2011 and 2015 TIMSS assessments were compared to 2019 data to explore trends and generalizability, while only 2019 data were used in further statistical analyses. Data preparation and analysis involved multiple steps. Once imported into SPSS, data were cleaned for missing and unusable values on 35 selected independent variables (IVs). Multiple science achievement scores were compared, and average scores were selected as the dependent variable (DV). Scale scores were calculated for sets of items in the Student (STQ, Teacher (TQ), and School (SCQ) Questionnaires. Outlier and multicollinearity analyses, and tests of regression assumptions were performed. For Research Question 1, bivariate correlations examined the relationships between IVs and science achievement; IVs with a weak relationship were dropped from further analyses. For Research Question 2, regression explored how IVs explained the variance in science achievement scores for the total sample. For Research Question 3, hierarchical regression analyses were conducted separately for male and female subsamples to identify factors that explained gender differences in science achievement. Results for Research Question 1 indicated significant correlations between selected independent variables (IVs) and science achievement: STQ: 9 of 13 IVs; TQ: 6 of 12 IVs; and SCQ: 4 of 10 IVs. Among IVs from the STQ, parental education emerged as the strongest predictor. Gender was negatively correlated, with female students outperforming males. Several TQ IVs showed weaker associations, but the percentage of students taught biology was the strongest iv positive correlate with science achievement. The SCQ IVs showed minimal correlations, with weak positive relationships to an emphasis on academic success and slight negative correlations with resource shortages. These results indicated that family background plays a crucial role in science achievement, while the availability of school resources, school culture, attention to subject matter, and effectiveness of science instruction also contributed. Results for Research Question 2 indicated that STQ IVs (Set A) were the most significant contributors to explaining the variance in eighth-grade science achievement on the TIMSS 2019 assessments (24.5%). Parental education, student gender, and parental country of birth were the strongest predictors. When TQ IVs (Set B) were added, the explained variance increased slightly to 24.9%, with the teacher’s need for professional development and the percentage of students taught biology having a modest effect. Adding SCQ IVs (Set C) increased the explained variance to 27.4%, but their contribution was minimal, with instructional hours and resource shortages having only slight negative impacts. Overall, student background characteristics, particularly parental education and gender, had the most substantial influence on science achievement, while teacher and school factors contributed to a lesser extent. The sample size for analyses varied as the regression models progressed, with the final regression model including data from a reduced subset of 10 significant predictors from the larger set of 19 significant correlates. Findings for Research Question 3 highlight the significant influence of STQ IVs, such as parental education and country of origin, on gender differences in v eighth-grade science achievement scores. For male students (n=792), these factors, particularly the country of birth, explained 19% of the variance in science achievement. For female students (n=935), family background, especially the country of birth of Parent A and the number of books at home, accounted for 23.5% of the variance. Gender-specific differences were observed, with male students\u27 performance being more influenced by the country of birth of both the student and Parent B, while female students were more affected by parental education and home resources. Gender was found to moderate the impact of several predictors, notably family background factors, underscoring the need for targeted interventions for male and for female students to improve science achievement. In conclusion, this study highlights the role and contribution of parental education, home resources, and teacher professional development in shaping academic achievement in Saudi Arabia. While the findings contribute valuable insights to current educational research, limitations such as missing data and the inability to fully explore causal mechanisms must be considered. Future research should address these gaps and explore the broader applicability of the results. The study’s recommendations for policy and practice emphasize the need for targeted support for students, especially those from disadvantaged backgrounds, and continuous professional development for teachers, ensuring that all students have equal opportunities to excel in science education