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Elastically Deformable Components And Assemblies For Use In Cellular Assays
Full text linkThe present invention provides elastic assemblies used to model tissues or organs of interest. In one embodiment, detailed herein, the assemblies are designed to model the blood brain barrier following a traumatic brain injury. The present invention also provides elastic membranes on which the assemblies are built, kits from which the assemblies may be prepared, and systems that expand upon the assemblies, forming more physiologically relevant models. Methods for making and using the disclosed devices are also provided
Determining the Flavor Thresholds of Iron Sulfate and Iron (III) Chloride in Nonalcoholic Beer
Full text linkThe production of India Pale Ales (IPAs) has significantly grown within the U.S. craft beer industry, with IPAs accounting for nearly 44% of the total craft beer production by 2022. This increase in IPA production correlates with a rise in U.S. aroma hop cultivation, as IPAs typically undergo dry hopping, a process that enhances their aromatic profile. In a study conducted by Lafontaine et al., (2022), it was found that different hop cultivars can impact levels of metallic character in a final product from dry hopping. When specifically analyzing iron concentrations, it can be seen that the ranges of iron in dry hopped be varied from 10.9-40.4µg/L depending on the beer style and hop cultivar. However, due to lack of research in flavor thresholds for beer, brewers are currently unaware of the specific concentration levels at which these transition metals begin to negatively impact the flavor characteristics of their beer. This lack of clarity makes it difficult for brewers to control metal concentrations effectively and avoid undesirable off-flavors. This study aims to determine the flavor thresholds of iron sulfate (FeSO₄) and iron III chloride (FeCl₃) in nonalcoholic beer (NAB). A sensory analysis involving 22 panelists was conducted using a triangle test methodology to assess detection thresholds for these two transition metals. Results showed that the detection thresholds for FeSO₄ ranged from 75.52-605.28 µg/L, while FeCl₃ ranged from 47.48-818.83 µg/L, with all observed thresholds exceeding typical iron concentrations found in dry-hopped beers (Lafontaine et al., 2022). These findings suggest that iron alone does not contribute to metallic off-flavors in beer. However, the study indicates a need for further research into the interaction of iron with other transition metals in beer, which may affect flavor perception. This research provides valuable data for brewers to refine metal concentrations in beer production, potentially enhancing sensory quality in both alcoholic and non-alcoholic beers
The Effect of Self-Esteem and Social Ostracism on Conspiratorial Thinking
Full text linkWith the rise of misinformation in America today, conspiracy theories and the conditions that influence them have increasingly become a topic of focus for researchers. This study investigated whether social exclusion increases belief in conspiracy theories, and how this relationship is impact by self-esteem among other individual factors. Participants (N = 309) were randomly assigned to recall either a personal experience of social exclusion or their last trip to the grocery store. They then completed randomized measures assessing conspiratorial beliefs, self-esteem, loneliness, and need for uniqueness. Contrary to expectations, no significant differences were found between the exclusion and control groups in relation to conspiratorial attitudes. The manipulation check also failed to produce a significant difference in reported feelings of exclusion between the two groups, suggesting the experimental manipulation was ineffective. These findings limit the interpretability of the results but underscore the need to refine future experimental designs. As conspiratorial thinking continues to rise in social and political discourse, understanding its psychological underpinnings remains an urgent and necessary direction for future research
Assessment of Nitrogen Source Utilization During Nitrogen Fixation and Nitrogenase Regulation by Methanosarcina acetivorans
Full text linkNitrogen is a crucial element in biomolecules such as proteins and DNA, essential for all cellular life. Biological nitrogen fixation, a process utilized by certain bacteria and archaea, reduces dinitrogen (N₂) to ammonia (NH₃), enabling growth in the absence of fixed nitrogen sources like NH₃. This process is driven by the metalloenzyme nitrogenase, which catalyzes the reaction: N₂ + 16ATP + 8e⁻ + 8H⁺ → 2NH₃ + H₂ + 16ADP + 16Pi. Due to its high energy demand, nitrogenase production and activity are tightly regulated. Among archaea, nitrogenase is found exclusively in methanogens, where its regulation remains poorly understood. We employed Methanosarcina acetivorans as a model organism to investigate fixed nitrogen source utilization and nitrogenase regulation in methanogens. Using a mutant strain of M. acetivorans incapable of fixing N₂, we assessed the utilization of various nitrogen sources, including all 20 common amino acids and biologically relevant inorganic nitrogen compounds (e.g., nitrate). Surprisingly, only glutamine, trimethylamine (also a carbon source), and NH₃ supported the growth of the mutant strain, indicating a narrow range of fixed nitrogen source utilization in M. acetivorans. Notably, growth with glutamine as the sole nitrogen source was poor compared to NH₃. Further investigation using another mutant strain deficient in hydrogenase activity revealed H₂ production during growth with glutamine, suggesting functional nitrogenase activity despite the presence of glutamine as a fixed nitrogen source. Thus, in the absence of NH₃ or trimethylamine, M. acetivorans resorts to energy-intensive N₂ fixation, even when provided with a significant concentration of glutamine, a usable fixed nitrogen source and key intermediate in nitrogen assimilation. However, upon reexamining growth with glutamine as the sole nitrogen source, the results differed from initial observations. The previously noted poor growth was attributed to an inadequate glutamine concentration. Future studies will investigate how increased glutamine levels affect nitrogenase activity
The Rise of Fitspiration: An Examination of Social Media Influence, Body Image Concerns, and Online Harassment
Full text linkThe fitspiration movement on social media has raised concerns about potential body image satisfaction issues and body standard internalization. The potential negative effects of body image dissatisfaction include disordered eating, excessive exercise, anxiety, depression, and a risk to online harassment victimization. This dissatisfaction from fitspiration is reinforced by pressures from family and friends. Relying on data from 347 respondents, the present study explores the potential relationship between fitspiration content consumption, body image dissatisfaction, social pressures, and experiences of online harassment. Bivariate correlations and regression analysis were employed to examine the connections between the variables. Results indicated that there was a significant, positive correlation between fitspiration and body image dissatisfaction. There was also a significant and positive correlation between body image dissatisfaction and online harassment. This is consistent with previous research, revealing larger, societal implications surrounding social media trends and their influence on thoughts, feelings, and behaviors. Future research is needed to determine what avenues could mitigate body image dissatisfaction and the pressures from social media
The Relationship Between Food Allergies and Intolerances and the Development of Disordered Eating Patterns
Full text linkFood allergies and food intolerances are becoming an increasingly more prevalent issue in the Unites States. To mitigate adverse reactions, these individuals often eliminate food or food groups from their diets and the ramifications of these lifestyle changes may result in disordered eating patterns. In regard to food allergies and intolerances and eating disorders, it is reasonable to suggest that the overlapping lifestyle choices and physical, social, and emotional ramifications may lead to a correlation between the two phenomena. This study explores the relationship between food allergic and food intolerant individuals and disordered eating habits among college students. Survey results from this study found a positive correlation between avoiding food and disordered eating patterns, which indicates a need to explore further relationships between diet elimination and disordered eating patterns among college students
Utilizing 16s Ribosomal RNA Sequencing to Identify Bacterial Species Colonizing Lame Birds with Bacterial Chondronecrosis with Osteomyelitis
Full text linkBroiler chicken lameness has become prevalent in recent years due to high growth rates in broilerchickens. Bacterial chondronecrosis with osteomyelitis (BCO), the main cause of lameness, is characterized by necrosis of femoral and tibial heads in affected birds. Heavier birds are more susceptible to mechanical stress in these regions, which results in microfractures, leading to lameness. BCO lameness poses huge financial pressure to the poultry industry, as 14-50% of flocks can become affected during outbreaks. The purpose of this experiment was to identify bacterial species present in birds with BCO lameness. A total of 1,560 chicks were randomly distributed into 26 pens, 2 with wire floors and 24 with litter floors. The wire-flooring acted as a positive control to spread the lameness-causing bacteria through aerosol to birds raised on litter floor pens for feed treatments. During this study, birds that were unable to walk when prompted were diagnosed as lame and culled. All lame birds were necropsied, and bacteria were isolated from the blood and bone lesions found on the femoral and tibial heads. Once bacteria were grown on agar plates, individual colonies were re-cultured for further species identification using 16s ribosomal RNA sequencing. The results showed that the main bacterial species causing lameness in this research trial were Staphylococcus spp., Enterococcus spp., and Escherichia coli. Identifying the bacterial species causing lameness is crucial to help develop mitigation measures to reduce lameness in broiler chickens. Thus, this experiment is anticipated to help develop BCO treatments that strengthen the bone and improve the immune response against distinct bacteria. More research is needed to study the virulence of Staphylococcus spp., Enterococcus spp., and Escherichia coli to reduce lameness caused by bacterial infection
A Novel Approach to Attention-Based Models in Image Completion: Weighted Spatial-Attention Using Radial Distance
Full text linkHumans infer missing visual information by focusing on spatial relationships in the context of their surroundings. Machine learning aims to replicate this skill through image completion, a fundamental task in current computer vision research. While advances in self-attention layers have recently enhanced generative machine learning models for text, these mechanisms still currently lack the capability to handle sparse image completion efficiently. We introduce a distance-based attention mechanism that uses radial-based weights to efficiently reconstruct an image. We compare this attention mechanism with self-attention and a fully connected network on an image completion task using the MNIST dataset. Our results show that the weighted spatial-attention mechanism outperformed both models, producing more accurate reconstructions with greater efficiency
Personalized Model of Cardiac Fibroblast Signaling Using Patient-Specific Data
Full text linkHeart disease is the leading cause of death worldwide for both men and women, and cardiac fibroblasts are critical to heart form and function. Essential roles of cardiac fibroblasts include cell-cell communication, cell-cell signaling, and synthesizing and degrading the extracellular matrix (ECM), which controls structural support and tissue repair of the heart. Abnormal fibroblast signaling can lead to negative impacts, including fibrosis, impaired heart function, and inflammation. A computational model of cardiac fibroblast signaling on Netflux and MATLAB software was adapted and utilized to determine the effect of patient-specific levels of cytokines, hormones, growth factors, peptides, and membrane tension on the ECM. This model integrates 191 reactions and 121 nodes, with 11 inputs that result in 19 outputs describing ECM impacts. Typical values for each of the 11 inputs, as well as standard deviation data produced the 500 random computer-generated patients that were analyzed. Cluster analysis, including hierarchical clustering and principal component analysis (PCA), were performed to determine if certain subgroups of patients had similar ECM responses. PCA analysis provided the clearest clusters, with one cluster of patients resulting in lower ECM responses on average. ECM nodes were split into groups based on average activity level, and a system model on Cytoscape revealed four transcriptional regulation nodes associated with high-activity ECM nodes. In sum, this work advanced our understanding of patient-specific differences in cardiac fibroblast signaling related to fibrotic disease
Do Perceptions Affect Outcomes in Patients with Metabolic-Associated Steatotic Liver Disease? A Clinical Inquiry.
Full text linkAbstract
BACKGROUND & AIMS: Metabolic-associated steatotic liver disease is a chronic condition that often coexists with metabolic disorders and impacts a significant portion of the global population. The literature indicates that patients’ perceptions are linked to outcomes; however, there is a gap in the literature examining the influence of these perceptions on the outcomes of metabolic-associated steatotic liver disease. This clinical inquiry investigated this relationship.
METHODS: Data collection occurred between January and February 2025 in a primary care setting, utilizing a 5-point Likert scale of patients’ perceptions of care, disease severity, and self-efficacy. Patients were identified through a retrospective chart review and were approached for the perceptions survey. The participating Federally Qualified Health Center has participated in several clinical trials addressing metabolic-associated steatotic liver disease. Participants were separated depending on whether they had previously participated in one of the clinical trials or not. Perception scores were compared to hemoglobin A1C, aspartate transferase, alanine transaminase, and body mass index. Descriptive statistics were conducted to conclude how patients’ perceptions influence outcomes.
RESULTS: Seven participants completed the survey. Mean perception scores for those previously enrolled in a clinical trial compared to those not enrolled include the following: perceptions of care (5.0 vs. 4.5), perceptions of disease severity (2.3 vs. 3.8), and perceptions of self-efficacy (5.0 vs. 4.25). A positive correlation was found in hemoglobin A1C (Durbin-Watson = 1) with no correlation in body mass index (Durbin-Watson = 2.23) for those enrolled in a clinical trial. A negative correlation was found in hemoglobin A1C (Durbin-Watson = 2.781) and body mass index (Durbin-Watson = 2.95) for those not enrolled in a clinical trial.
CONCLUSION: Positive patient perceptions may improve outcomes in those at risk for or diagnosed with metabolic dysfunction-associated steatotic liver disease. Strategies should focus on enhancing patient self-motivation and coping skills to mitigate health risks associated with this disease