Antifungal resistance patterns of two human yeast strains isolated from the International Space Station (ISS).

This report was designed to compare spaceflight-induced cellular and physiological adaptations of two human yeast commensals, Candida parapsilosis and Rhodotorula mucilaginosa isolated from the International Space Station. These two yeast strains are common opportunistic pathogens responsible for a variety of superficial infections as well as systemic and more severe infections in immunocompromised individuals. The risk of opportunistic infections can be assessed by testing antifungal susceptibility as a virulence-related phenotype. In this study, antifungal susceptibility was tested using a broth dilution method which included different concentrations of the common antifungals Fluconazole, Amphotericin B, and Caspofungin in strains from the ISS and compared to earth isolates from the American Type Culture Collection (ATCC) library. Preliminary results indicate that, in general, both yeast isolates from the ISS demonstrated increased resistance to all antifungals tested when compared to earth isolates. This study provides insight into deciphering the microbial responses to spaceflight conditions and their potential role in causing antimicrobial-resistant infections

Quantitative Measurement of Marine and Fungal Biofilm Dynamics: Insights into Ecological and Biomedical Implications

The formation of biofilms by marine and fungal organisms, including four marine Vibrio isolates and fungal isolates of Candida and Rhodotorula, represents complex ecosystems with significant implications for ecology and biomedicine. This study aimed to enhance the understanding of biofilm dynamics through accurate and comprehensive measurement techniques. Following inoculation and growth in liquid media, biofilms were developed in 96-well microplates and stained with crystal violet. The stained biofilms were then solubilized with isopropanol, and optical density measurements were used to quantify the absorbance relative to biofilm concentration. Notably, optical density readings indicated an increased amount of fungal biofilm formation when compared to marine bacterial biofilms, with statistical significance (p\u3c0.05). This finding underscores the differential biofilm formation capacities among marine and fungal isolates, highlighting the importance of advanced quantitative techniques in revealing the structure, function, and ecological significance of biofilms. The study suggests potential applications in environmental and health-related fields and calls for further research into the molecular mechanisms underlying biofilm resilience and pathogenicity. Keywords: Biofilms, Marine Vibrio, Candida, Rhodotorula, Crystal Violet, Optical Density, Comparative Analysi

Comparison of Salivary Cortisol Levels in Various Academic Majors Using Enzyme-Linked Immunosorbent Assay

Keywords: Cortisol, Stress, ELISA The purpose of this study was to examine the impact that different majors at Embry-Riddle Aeronautical University have on salivary cortisol levels. Cortisol is a glucocorticoid synthesized in the zona fasciculata of the adrenal cortex. Secretion of cortisol is regulated by a hypothalamic hormone and a pituitary hormone. Corticotropin-releasing hormone (CRH) is released from the hypothalamus, and adrenocorticotropic hormone (ACTH) is released from the pituitary gland. Cortisol is a stress hormone that is secreted in response to a physical or emotional stressor. Different academic majors were anticipated to have different salivary cortisol levels when tested with competitive enzyme-linked immunosorbent assay (ELISA). Competitive ELISA uses cortisol standards and salivary samples to compete with cortisol conjugated to horseradish peroxidase to detect binding sites on a microtitre plate with coated anti-Cortisol antibodies. Bounded cortisol enzyme conjugates are measured by the reaction to the peroxidase to the substrate tetramethylbenzidine (TMB). Optical density is read on a plate reader, and the amount of cortisol in the sample is inversely proportional to the amount of enzyme conjugate detected from the plate well. The characterization of cortisol levels is classified by utilizing a standard curve line. Preliminary data indicates that cortisol levels are drastically increased in engineering majors and during morning lectures or laboratory classes. Future studies will include screening of a larger student population size for a more statistically accurate screening

Phenotypical Effects of Chronic Exposure of Escherichia Coli to Simulated Microgravity

Organismal adaptation to space conditions, increased background radiation and microgravity, present multiple questions as we plan longer stays in space. Just like other areas of research, we can use bacteria such as Escherichia coli to study adaptations to the chronic, or long-term, exposure to microgravity. Using this model, we kept exponentially growing cultures for up to 24 days under simulated gravity on a 2D clinostat, including a gravity control, aiming to study phenotypic and gene expression changes to characterize E. coli’s homeostatic control. For this purpose, we grew E. coli on nutrient broth with daily re-inoculation and measure the daily accumulation of cells using spectrophotometry and plate counts. Every 5 days we sampled cells for long-term storage in 25% glycerol -80℃. After the completion of the experiment, frozen cultures were re-streaked and tested for their ability to form biofilms, to grow at pH 4.5 and to survive an oxidative stress challenge. Understanding how E. coli responds to various stressors after growing under microgravity can provide future grounds for studying other metabolic processes such as an increase in antibiotic resistance

Drug Repurposing in Mycology: Identification of Compounds as Potential Antifungals Against Yeast Strains Isolated From the International Space Station

The emergence in antimicrobial resistance has become an increased problem as a consequence to human vulnerability to fungal infections. Human commensal microbes (those who in normal conditions do not cause any infection, including yeast) have become opportunistic pathogens when patients become immunocompromised. It has been previously reported that commensal yeast strains can become pathogenic when exposed to extreme environments, such as fluctuations in temperature, oxygen availability and microgravity; conditions that astronauts experience during space flight missions. As a consequence, strains that commonly do not cause disease then become a serious health concern. Moreover, the use of conventional antifungal drugs such as azoles and polyenes can lead to clinical failure and difficulties related to treating fungal infections, and combined with the time required to develop new drugs, we require urgent consideration of other therapeutic alternatives. Drug repurposing is a promising and fast solution that the scientific community can use with low cost and safety advantages. In the present study, we tested multiple NSAID (non steroidal, anti-inflammatory drugs) as potential candidates for antifungal activity. We tested the efficacy of Finasteride, Flufenamic acid, Quinacrine and Colistin against two yeast strains isolated from the International Space Station (Candida parapsilosis and Rhodotorula mucilaginosa) in an effort to decipher the best repurposing strategy to treat potential fungal infections

Latin American immigrants in Indianapolis: Perceptions of prejudice and discrimination

The article focuses on immigrants’ interactions with the Indiana natives, with emphasis in the city of Indianapolis and its suburbs. More specifically, this study aims at providing an understanding of the experiences of Latin American immigrants with special attention to perceptions of prejudice and discrimination and to feelings of social exclusion. A substantial proportion of Latin American immigrants interviewed indicated that they considered Indiana natives to be prejudiced and that they had personally experienced discrimination. The study reveals specific examples of discrimination experienced by the immigrants at the work place, in housing, in stores, restaurants and by various service providers. The results of the study demonstrate the relevance of the normative and power resource theories to explain prejudice and discrimination

Long- and short-range correlations and their event-scale dependence in high-multiplicity pp collisions at 1as = 13 TeV

Two-particle angular correlations are measured in high-multiplicity proton-proton collisions at s = 13 TeV by the ALICE Collaboration. The yields of particle pairs at short-( 06\u3b7 3c 0) and long-range (1.6 < | 06\u3b7| < 1.8) in pseudorapidity are extracted on the near-side ( 06\u3c6 3c 0). They are reported as a function of transverse momentum (pT) in the range 1 < pT< 4 GeV/c. Furthermore, the event-scale dependence is studied for the first time by requiring the presence of high-pT leading particles or jets for varying pT thresholds. The results demonstrate that the long-range \u201cridge\u201d yield, possibly related to the collective behavior of the system, is present in events with high-pT processes as well. The magnitudes of the short- and long-range yields are found to grow with the event scale. The results are compared to EPOS LHC and PYTHIA 8 calculations, with and without string-shoving interactions. It is found that while both models describe the qualitative trends in the data, calculations from EPOS LHC show a better quantitative agreement for the pT dependency, while overestimating the event-scale dependency. [Figure not available: see fulltext.

Measurement of the production of (anti)nuclei in p–Pb collisions at sNN=8.16TeV

Measurements of (anti)proton, (anti)deuteron, and (anti)3He production in the rapidity range -1 > y > 0 as a function of the transverse momentum and event multiplicity in p–Pb collisions at a center-of-mass energy per nucleon–nucleon pair sqrt(sNN) = 8.16 TeV are presented. The coalescence parameters B2 and B3, measured as a function of the transverse momentum per nucleon and of the mean charged-particle multiplicity density, confirm a smooth evolution from low to high multiplicity across different collision systems and energies. The ratios between (anti)deuteron and (anti)3He yields and those of (anti)protons are also reported as a function of the mean charged-particle multiplicity density. A comparison with the predictions of the statistical hadronization and coalescence models for different collision systems and center-of-mass energies favors the coalescence description for the deuteron-to-proton yield ratio with respect to the canonical statistical model