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Inactivation of Aerosolized Hepatitis A Viral Droplets on Food Contact Surfaces by Ultraviolet-Light-Emitting Diodes at 255 nm and 279 nm
No full textHepatitis A viral outbreaks continue to occur. It can be transmitted through aerosolized droplets and thus can contaminate surfaces and the environment. Ultraviolet light emitting diode (UV-C LED) systems are used for inactivation of microbes, though research is needed to determine optimal doses for aerosolized HAV inactivation. This study evaluates the UV-C LED doses for the inactivation of aerosolized hepatitis A virus (HAV) deposited on stainless-steel and glass discs. HAV was aseptically deposited onto stainless-steel or glass discs (1.27 cm diameter) using a nebulizer within a chamber followed by treatments for up to 1.5 min with 255 nm (surface dose = 0–76.5 mJ/cm2) or 279 nm (surface dose = 0–8.1 mJ/cm2) UV-C LED. Plaque assays were used to enumerate infectious titers of recovered viruses and data from three replicates were statistically analyzed. The calculated linear D10-value (UV-C dose for a 1-log reduction in aerosolized deposits) for HAV by 255 nm UV-C LED was 47.39 ± 7.40 and 40.0 ± 2.94 mJ/cm2 (R2 = 0.94 and 0.91) and using 279 nm UV-C LED were 6.60 ± 0.27 and 5.57 ± 0.74 mJ/cm2 (R2 = 0.98 and 0.94) on stainless-steel and glass discs, respectively. The non-linear Weibull model showed δ (dose needed for a 1-log reduction in aerosolized HAV deposits) values for HAV of 29.69 ± 5.49 and 35.25 ± 15.01 mJ/cm2 by 255 nm UV-C LED (R2 = 0.99 and 0.92) and 6.67 ± 0.63 and 5.21 ± 1.25 mJ/cm2 by 279 nm UV-C LED (R2 = 0.98 and 0.95) on stainless-steel and glass discs, respectively. These data indicate that 279 nm UV-C LED showed higher efficiency for HAV inactivation than 255 nm UV-C LED, and that Weibull models were a better fit when tailing was observed. This study provides the inactivation data needed to aid in designing UV-C LED systems for delivering doses required to inactivate bio-aerosolized HAV deposits on stainless-steel and glass
Crop classification in South Korea for multitemporal PlanetScope imagery using SFC-DenseNet-AM
Full text linkIn this manuscript, a new methodology based on a deep learning model using a Siamese network and attention module was proposed to classify crop cultivation areas, such as onion and garlic, from multitemporal PlanetScope images in South Korea. To consider the seasonal characteristics of crops in the model, training data were constructed from multitemporal satellite images. It was generated using PlanetScope satellite imagery from January and April, corresponding to the seasonal growth period of onion and garlic, in South Korea. Image patches were generated by considering the ratio of crops to minimize the influence of imbalanced data in the training process. Siamese FC-DenseNet with an attention module model (SFC-DenseNet-AM) is proposed, and the attention module is used to classify cultivated crop areas. Based on the proposed network, we extract cultivated crop areas using preliminary cultivation information. The results of the experiment using PlanetScope images indicate that image classification for cultivated areas was effectively performed using the proposed deep learning model. The model\u27s performance, with F1-scores of 0.823 (garlic) and 0.774 (onion), was verified through an ablation study
Chronic High-Salt Diet Activates Tumor-Initiating Stem Cells Leading to Breast Cancer Proliferation
Full text linkSeveral chronic inflammatory diseases have been linked to high-salt (HS) diets. Chronic inflammation is an established causative hallmark of cancer. However, a direct role of HS diets in tumorigenesis is yet to be defined. Previous orthotopic murine breast tumor studies have shown that short-term HS diets caused inhibition of tumor growth through the activation of cytotoxic adaptive immune responses. However, there have been experimental challenges in developing a viable chronic HS-diet-based murine tumor model. To address this, we have developed a novel chronic HS diet tumor model through the sequential passaging of tumor cells in mice under HS dietary conditions. Two orthotopic murine triple-negative breast cancer models, 4T1 tumor cells injected into BALB/c mice and Py230 tumor cells injected into C57Bl/6 mice, were utilized in our study. For the HS diet cohort, prior to orthotopic injection with tumor cells, the mice were kept on a 4% NaCl diet for 2 weeks. For the regular salt (RS) diet cohort, the mice were kept on a 1% NaCl diet. Following syngeneic cancer cell injection, tumors were allowed to grow for 28 days, following which they were collected to isolate immune cell-depleted cancer cells (passage 1, P1). The tumor cells from P1 were reinjected into the next set of non-tumor-bearing mice. This procedure was repeated for three cycles (P2–P4). In P1, compared to the RS diet cohort, we observed reduced tumor kinetics in both murine tumor models on the HS diet. In contrast, by P4, there was significantly higher tumor progression in the HS diet cohort over the RS diet cohort. Flow cytometry analysis demonstrated an 8-fold increase in tumor-initiating stem cells (TISCs) from P1 to P4 of the HS diet cohort, while there were no significant change in TISC frequency with sequential passaging in the RS diet cohort. Molecular studies showed enhanced expression of TGFβR2 and CD80 on TISCs isolated from the P4 HS diet cohort. In vitro studies demonstrated that TGFβ stimulation of these TISCs increased the cellular expression of CD80 molecules. Further, the chronic HS diet selectively induced the glycolytic metabolic phenotype over the mitochondrial oxidative phosphorylation phenotype in TISCs, which is needed for the production of metabolites during tumor cell differentiation and proliferation. The infiltrating CD8 and CD4 T-lymphocytes in P4 tumors demonstrated increased expression of the immune checkpoint inhibitor (ICI) CTLA4, a known binding partner of CD80, to cause immune exhaustion and pro-tumorigenic effects. Interestingly, anti-TGFβ monoclonal antibodies (mAbs) played a synergistic role in further enhancing the anti-tumor effect of anti-CTLA4 mAb. In summary, our findings demonstrated that chronic HS diet increased the frequency of TISCs in tumors leading to blunting of cytotoxic adaptive immune responses causing tumor proliferation. Furthermore, a combination of anti-TGFβ with current ICI-based immunotherapies could exert more favorable anti-cancer clinical outcomes
0418201005a
No full texthttps://digitalscholarship.tnstate.edu/m-chamberlain-drawings/1019/thumbnail.jp
a darkening sky 20x24
No full texthttps://digitalscholarship.tnstate.edu/m-chamberlain-landscapes/1004/thumbnail.jp
Common Factors in Higher Education that Lead to LGBTQ+ Students’ Suicidal Ideation
No full textThe objective of this research was to gather the experiences of six participants from various 2-year and 4-year colleges in the state of Alabama. Participants were solicited using a flyer posted in-house and online to students who are members of the Equality and Advocacy Center (EAC) as well as the Acceptance of Diverse Population Center (ADPC). The purpose of this qualitative study was to understand the challenges LGBTQ+ students face in higher education due to mental health issues (e.g., victimization, rejection from peers and parents, self-belonging, depression, and anxiety) and suicidal ideation. Through the candid stories of LGBTQ+ college students, significant data was collected that shed light on how the adverse treatment from their peers negatively affect LGBTQ+ students. Also, this research study provided an understanding of the perceptions of the LGBTQ+ students regarding their needs to ensure their safety and minimize mental health challenges. This study can add to the body of literature regarding the challenges that lead to suicidal ideation as well as mental health struggles amongst LGBTQ+ students. This study gave a voice to current and future LGBTQ+ students who experience challenges with mental health and suicidal ideations. Finally, the study explored preventative methods that could be used by higher education administrators to address LGBTQ+ students who have suicidal ideations. The findings from this research study can allow college administrators the ability to make sound research-based decisions regarding resources for LGBTQ+ students