34 research outputs found
Technical feasibility study for development of chlorine dioxide releasing packaging system and its application in decontaminating fresh produce
No full textA feasibility study was conducted to develop chlorine dioxide (ClO2) releasing packaging films for decontaminating fresh produce. Sodium chlorite and citric acid powder were incorporated into polylactic acid (PLA) polymer. Films made with different amount of PLA (100 and 300 mg), percentage of reactant (5-60%), and ratios of sodium chlorite to citric acid (1:2 or 2:1) were prepared using a solvent casting method. The release of ClO2 from the resultant films was activated by moisture. Increase of reactants in the films produced more ClO2 while higher PLA content in the films resulted in less release of ClO2. The ratio of sodium chlorite to citric acid and activation temperature (22°C vs. 10°C) didn’t affect the ClO2 release from the films. Antimicrobial efficacy of ClO2 released from the films was evaluated using grape tomato as a model food. The results indicate that the films were activated by moisture from tomatoes in the package and the released ClO2 reduced Salmonella spp. and E. coli O157:H7 inoculated on the tomatoes to undetectable levels (< 5 CFU/tomato), achieving more than 3 log reduction. The film-treated tomatoes did not show significant changes in color and texture as compared to controls during storage at 10°C for 21 days. This study demonstrated the technical feasibility for development of gaseous chlorine dioxide releasing packaging system to enhance microbial safety and extend shelf life of fresh produce.M.S.Includes bibliographical referencesby Soumi Ra
Ionic conductivity of sodium silicate glasses grown within confined volume of mesoporous silica template
No full textNanodimensional sodium silicate glasses of composition 30Na2O.70SiO2 has been prepared within the pores of 5.5 nm of mesoporous silica as a template using the surfactant P123. The nanocomposite was characterized by X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectroscopy. Electrical conductivity of the sample was studied by ac impedance spectroscopy. The activation energy for ionic conduction was found to be 0.13 eV with dc conductivity at room temperature of 10-6 S-cm-1. This is attributed to the creation of oxygen ion vacancies at the interface of mesoporous silica and nanoglass arising out of the presence of Si2+ species in the system. These nanocomposites are expected to be useful for applications in sodiumion battery for storage of renewable energy
Empowering Students Through Questioning: Enhancing Literacy and Metacognition with the Kylene Beers’ 3 Big Questions Strategy
No full textThis summary paper shares key ideas from one of the sessions at the 17th annual Bill Martin Jr.Symposium. The presenter focused on using questioning to promote critical thinking among students while engaging with nonfiction text and finding evidence to support the primary claim. The session focused on Kylene Beers’, a renowned author and educator, “The 3 Big Questions’ strategy” to encourage inquiry and reflection, facilitate knowledge construction, and foster transferable skills across disciplines. Literacy educators are always looking for ways to empower their students to be critical readers of text as they think deeply about what they are reading. Students practice with the 3 big questions answer and reflect on the following questions: “What surprised you?” What did the author think I already knew?” and “What changed, challenged, or confirmed what I already knew?” Once students are comfortable with responding to these questions, they can use these reflection questions to deepen their understanding whenever they read informational texts. Encouraging students to ponder these questions can deepen their grasp of the text and foster metacognitive awareness and inquiry. This presentation aimed to empower middle school educators to teach courageously with tools that facilitate meaningful discussions and comprehension activities around texts, ultimately enhancing students’ literacy skills and fostering critical thinking about their own thinking processes
Monsoons to Mixing in the Bay of Bengal Multiscale Air-Sea Interactions and Monsoon Predictability
No full textSkillful prediction of the ``active'' and ``break'' spells of monsoon intraseasonal oscillations during the South Asian monsoon season is crucial for the socio-economic fate of one-sixth of the world's population, yet it remains a grand challenge problem. The limited skill of our coupled weather and climate models is largely due to our inability to represent the complex multiscale interactions of the north Indian Ocean and the atmosphere. Air-sea interactions are at the heart of not only the climatological mean annual cycle of the South Asian monsoon but also its synoptic, subseasonal, interannual, and decadal variability. With high local monsoon precipitation and discharge from major rivers (Ganges-Brahmaputra, Irrawaddy), the Bay of Bengal (BoB) exhibits the lowest surface salinities in the tropics as well as unique thermal stratification, making it a natural laboratory for studying multiscale interactions ranging from planetary-scale monsoons to submesoscale mixing in freshwater pools. The current ocean component of coupled models is inadequate for simulating the BoB's upper-ocean thermal structure with fidelity. To further improve monsoon forecasts on intraseasonal and interannual time scales, we need new high-resolution and high-frequency observations over the BoB to fill the gap in our understanding of how the ocean mixes in highly fresh regions, and we need modeling of processes that will convert this understanding to parameterizations of mixing that can be used to improve large-scale ocean models
Structural insight into <i>Mycobacterium tuberculosis</i> maltosyl transferase inhibitors: pharmacophore-based virtual screening, docking, and molecular dynamics simulations
No full text<div><p>Pharmacophore-based virtual screening, subsequent docking, and molecular dynamics (MD) simulations have been done to identify potential inhibitors of maltosyl transferase of <i>Mycobacterium tuberculosis</i> (mtb GlgE). Ligand and structure-based pharmacophore models representing its primary binding site (pbs) and unique secondary binding site 2 (sbs2), respectively, were constructed based on the three dimensional structure of mtb GlgE. These pharmacophore models were further used for screening of ZINC and antituberculosis compounds database (ATD). Virtually screened molecules satisfying Lipinski’s rule of five were then analyzed using docking studies and have identified 23 molecules with better binding affinity than its natural substrate, maltose. Four top scoring ligands from ZINC and ATD that either binds to pbs or sbs2 have been subjected to 10 ns each MD simulations and binding free energy calculations. Results of these studies have confirmed stable protein ligand binding. Results reported in the article are likely to be helpful in antitubercular therapeutic development research.</p></div
Reciprocity between Regulatory T Cells and Th17 Cells: Relevance to Polarized Immunity in Leprosy
No full textEffects of glyphosate and cylindrospermopsin at environmental concentrations on growth, photosynthesis and mineral content in lettuce plants
Get PDFGlyphosate is the most widely used herbicide, mainly due to the extensive cultivation of glyphosate resistant plants. The intensification of agriculture has increased water eutrophication and the presence of natural cyanobacterial toxins, such as ylindrospermopsin. Previous studies support the hypothesis that glyphosate and cylindrospermopsin can affect the yield of crop plants, depending on the exposure concentration. Lettuce (Lactuca sativa L.)info:eu-repo/semantics/publishedVersio
Reciprocity between Regulatory T Cells and Th17 Cells: Relevance to Polarized Immunity in Leprosy.
No full textT cell defect is a common feature in lepromatous or borderline lepromatous leprosy (LL/BL) patients in contrast to tuberculoid or borderline tuberculoid type (TT/BT) patients. Tuberculoid leprosy is characterized by strong Th1-type cell response with localized lesions whereas lepromatous leprosy is hallmarked by its selective Mycobacterium leprae specific T cell anergy leading to disseminated and progressive disease. FoxP3+ Regulatory T cells (Treg) which are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases also dampen proinflammatory T cells that include T helper 17 (Th17) cells. This study is aimed at evaluating the role of Treg cells in influencing other effector T cells and its relationship with the cytokine polarized state in leprosy patients. Peripheral blood mononuclear cells from of BT/TT (n = 15) and BL/LL (n = 15) patients were stimulated with M. leprae antigen (WCL) in presence of golgi transport inhibitor monensin for FACS based intracellular cytokine estimation. The frequency of Treg cells showed >5-fold increase in BL/LL in comparison to BT/TT and healthy contacts. These cells produced suppressive cytokine, IL-10 in BL/LL as opposed to BT/TT (p = 0.0200) indicating their suppressive function. The frequency of Th17 cells (CD4, CD45RO, IL-17) was, however, higher in BT/TT. Significant negative correlation (r = -0.68, P = 0.03) was also found between IL-10 of Treg cells and IL-17+ T cells in BL/LL. Blocking IL-10/TGF-β restored the IL-17+ T cells in BL/LL patients. Simultaneously, presence of Th17 related cytokines (TGF-β, IL-6, IL-17 and IL-23) decreased the number of FoxP3+ Treg cells concomitantly increasing IL-17 producing CD4+ cells in lepromatous leprosy. Higher frequency of Programmed Death-1/PD-1+ Treg cells and its ligand, PDL-1 in antigen presenting cells (APCs) was found in BL/LL patients. Inhibition of this pathway led to rescue of IFN-γ and IL-17 producing T cells. Results indicate that Treg cells are largely responsible for the kind of immunosuppression observed in BL/LL patients. This study also proves that Treg cells are profoundly affected by the cytokine milieu and this property may be utilized for benefit of the host
