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Advanced Analytical Method Development: From Highly-Enrolled Classroom To Data-Intensive Proteomics, Laxmi Sinduri Vuppala Jul 2022

Advanced Analytical Method Development: From Highly-Enrolled Classroom To Data-Intensive Proteomics, Laxmi Sinduri Vuppala

USF Tampa Graduate Theses and Dissertations

In analytical chemistry, method development is key to identifying, separating, and quantifying chemical components of interest systems. The chemical aspects are fundamental to understanding the subject of any analytical system, whether in academic research, industry, or government. These methodologies serve as a bridge between the classroom, where students are taught to be curious and enlightened, and research, where one strives to contribute. The Ph.D. dissertation integrates advanced methodologies in basic and applied research and advanced instrumentation, but the core criteria for validation remain the same. As part of chemical education curriculum development, a large cohort of undergraduates performed two gas …


Exchange Broadening Underlies The Enhancement Of Ide-Dependent Degradation Of Insulin By Anionic Membranes, Qiuchen Zheng, Bethany Lee, Micheal T. Kebede, Valerie A. Ivancic, Merc M. Kemeh, Henrique Lemos Brito, Donald E. Spratt, Noel D. Lazo Jul 2022

Exchange Broadening Underlies The Enhancement Of Ide-Dependent Degradation Of Insulin By Anionic Membranes, Qiuchen Zheng, Bethany Lee, Micheal T. Kebede, Valerie A. Ivancic, Merc M. Kemeh, Henrique Lemos Brito, Donald E. Spratt, Noel D. Lazo

Chemistry

Insulin-degrading enzyme (IDE) is an evolutionarily conserved ubiquitous zinc metalloprotease implicated in the efficient degradation of insulin monomer. However, IDE also degrades monomers of amyloidogenic peptides associated with disease, complicating the development of IDE inhibitors. In this work, we investigated the effects of the lipid composition of membranes on the IDE-dependent degradation of insulin. Kinetic analysis based on chromatography and insulin's helical circular dichroic signal showed that the presence of anionic lipids in membranes enhances IDE's activity toward insulin. Using NMR spectroscopy, we discovered that exchange broadening underlies the enhancement of IDE's activity. These findings, together with the adverse effects …


Structure-Property Investigations In Urea Tethered Iodinated Triphenylamines, Muhammad Saddam Hossain, Fiaz Ahmed, Stavros G. Karakalos, Mark D. Smith, Namrata Pant, Sophya V. Garashchuk, Andrew B, Greytak, Pablo Docampo, Linda S. Shimizu Jul 2022

Structure-Property Investigations In Urea Tethered Iodinated Triphenylamines, Muhammad Saddam Hossain, Fiaz Ahmed, Stavros G. Karakalos, Mark D. Smith, Namrata Pant, Sophya V. Garashchuk, Andrew B, Greytak, Pablo Docampo, Linda S. Shimizu

Faculty Publications

Herein, we report structural, computational, and conductivity studies on urea-directed self-assembled iodinated triphenylamine (TPA) derivatives. Despite numerous reports of conductive TPAs, the challenges of correlating their solid-state assembly with charge transport properties hinder the efficient design of new materials. In this work, we compare the assembled structures of a methylene urea bridged dimer of di-iodo TPA (1) and the corresponding methylene urea di-iodo TPA monomer (2) with a di-iodo mono aldehyde (3) control. These modifications lead to needle shaped crystals for 1 and 2 that are organized by urea hydrogen bonding, π⋯π stacking, I⋯I, and I⋯π interactions as determined by …


Computational, Synthetic And Spectroscopic Studies On Donor Acceptor Transition Metal Complexes, Ranjana Dangi Jul 2022

Computational, Synthetic And Spectroscopic Studies On Donor Acceptor Transition Metal Complexes, Ranjana Dangi

Chemistry and Chemical Biology ETDs

Fundamental advances in our ability to design and construct electronic components at the nanoscale will require new design paradigms. One proposed nanoscale electronic component is the molecular rectifier. Molecular and molecule-based electronic components are advantageous due to their ease of synthetic manipulation, and the fact that the size dimensions of molecules are inherently at the nanoscale (0.5 - 3nm). Our group has shown how the Donor-Bridge-Acceptor biradical approach can be used to derive key structure-property relationships that allow insight into the choice of bridge fragments for molecular rectification by using constitutional isomers of the donor-bridge-acceptor biradical (NN-Th-Py-SQ) (S=1/2 ortho-semiquinonate, …


Determining The 3d Structure And Dynamics Of Mouse Notch1 Epidermal Growth Factor-Like Repeat 26 Using Nuclear Magnetic Resonance Spectroscopy, Kendra D. Jenkins Jul 2022

Determining The 3d Structure And Dynamics Of Mouse Notch1 Epidermal Growth Factor-Like Repeat 26 Using Nuclear Magnetic Resonance Spectroscopy, Kendra D. Jenkins

LSU Doctoral Dissertations

NOTCH is a transmembrane protein that transmits signals between cells in direct contact and alters gene expression. The signaling pathway is important because it is involved in cell fate determination. The NOTCH1 extracellular domain has 36 epidermal growth factor-like (EGF) repeats that are responsible for ligand binding. Mutations in the EGF-like repeats cause various neurological and developmental disorders. NOTCH1 signaling initiates when DSL ligands bind to EGF11-12, the minimum Ligand Binding Domain (LBD). The Abruptex region of the NOTCH1 protein (EGF24-29) is a highly glycosylated, flexible region with calcium binding sites that regulates NOTCH1 signaling and binding by interacting with …


The Photoionization Dynamics, Electronic Spectroscopy, And Excited State Photochemistry Of Alco And Aloc, Vincent J. Esposito, Joseph S. Francisco Jul 2022

The Photoionization Dynamics, Electronic Spectroscopy, And Excited State Photochemistry Of Alco And Aloc, Vincent J. Esposito, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The high cosmic abundance of carbon monoxide (CO) and the ubiquitous nature of aluminum-coated dust grains sets the stage for the production of weakly bound triatomic molecules AlCO (X 2Π) and AlOC (X 2Π) in circumstellar envelopes of evolved stars. Following desorption of cold AlCO and AlOC from the dust grain surface, incoming stellar radiation in the 2–9 eV wavelength range (visible to vacuum ultraviolet) will drive various photochemical processes. Ionization to the singlet cation state will cause an immediate Al–X (X = C, O) bond dissociation to form Al+ (1S) and CO (X 1 …


Characterization Of Three-Dimensional Fractional Viscoelastic Models Through Complex Modulus Analysis And Polar Decomposition, Avradip Ghosh, Avinash Kumar Both, Chin Li Cheung Jul 2022

Characterization Of Three-Dimensional Fractional Viscoelastic Models Through Complex Modulus Analysis And Polar Decomposition, Avradip Ghosh, Avinash Kumar Both, Chin Li Cheung

Department of Chemistry: Faculty Publications

Soft materials such as gels, elastomers, and biological tissues have diverse applications in nature and technology due to their viscoelastic nature. These soft materials often exhibit complex rheology and display elastic and viscous characteristics when undergoing deformation. In recent years, fractional calculus has emerged as a promising tool to explain the viscoelastic behavior of soft materials. Scalar constants are primarily used to quantify viscoelastic elements such as springs and dashpots. However, in three-dimensional (3D) space, not all materials show the same elastic or viscoelastic properties in all directions, especially under elastic/viscoelastic wave propagation (or anisotropy). Though previously reported studies on …


Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan Jul 2022

Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

n this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the …


Quantifying Protein Quality To Understand Protein Homeostasis (Supplemental Data), Hsien-Jung Lavender Lin Jul 2022

Quantifying Protein Quality To Understand Protein Homeostasis (Supplemental Data), Hsien-Jung Lavender Lin

ScholarsArchive Data

This data set includes the supplementary data for chpaters 3 and 4 in the dissertation Quantifying Protein Quality to Understand Protein Homeostasis. It includes various excel worksheets that were used to generate the data reported in the dissertation. We make this data available to the public so anyone who wants to reproduce the results has the resources and access to other perspectives that weren't discussed in depth in the dissertation. Chapter 3 used mass-spectrometry to quantify the surface accessibility differences in human serum albumin (HSA)between patients with and without rheumatoid arthritis (RA). We found certain residues are less reactive …


Evaluation Of Silver Nanoparticles Attached To Methylene Blue As An Antimicrobial Agent And Its Cytotoxicity, Somon Hakimov Jul 2022

Evaluation Of Silver Nanoparticles Attached To Methylene Blue As An Antimicrobial Agent And Its Cytotoxicity, Somon Hakimov

Masters Theses & Specialist Projects

Antibiotics resistance is considered as one of the greatest public health challenges of our time. In this work, we have synthesized silver nanoparticles (Ag NPs) using pulsed liquid ablation in different medium of growth and later combined with methylene blue (MB) to evaluate its potential as an effective photodynamic therapy agent. Ag NPs were synthesized by pulsed laser ablation technique in Polyvinylpyrrolidone (PVP), citrate, and Polyvinyl alcohol (PVA). The Ag NPs were characterized using transmission electron microscopy (TEM), UV-Visible (UV-Vis), and photoluminescence (PL) spectra. Next, Ag NPs were coupled with MB and used to deactivate the Gram-negative bacteria, Escherichia coli …


Photocrosslinking Probes Proximity Of Thymine Modifiers Tethering Excitonically Coupled Dye Aggregates To Dna Holliday Junction, Shibani Basu, Keitel Cervantes-Salguero, Bernard Yurke, William B. Knowlton, Jeunghoon Lee, Olga A. Mass Jul 2022

Photocrosslinking Probes Proximity Of Thymine Modifiers Tethering Excitonically Coupled Dye Aggregates To Dna Holliday Junction, Shibani Basu, Keitel Cervantes-Salguero, Bernard Yurke, William B. Knowlton, Jeunghoon Lee, Olga A. Mass

Chemistry and Biochemistry Faculty Publications and Presentations

A DNA Holliday junction (HJ) has been used as a versatile scaffold to create a variety of covalently templated molecular dye aggregates exhibiting strong excitonic coupling. In these dye-DNA constructs, one way to attach dyes to DNA is to tether them via single long linkers to thymine modifiers incorporated in the core of the HJ. Here, using photoinduced [2 + 2] cycloaddition (photocrosslinking) between thymines, we investigated the relative positions of squaraine-labeled thymine modifiers in the core of the HJ, and whether the proximity of thymine modifiers correlated with the excitonic coupling strength in squaraine dimers. Photocrosslinking between squaraine-labeled thymine …


A New Class Of Antibiotic That Prevents Drug Tolerance, Persistence, And Resistance By Controlling Emergence Of Phenotypes., Pankaj Dinkar Patil Jul 2022

A New Class Of Antibiotic That Prevents Drug Tolerance, Persistence, And Resistance By Controlling Emergence Of Phenotypes., Pankaj Dinkar Patil

Dissertations - ALL

The fight against bacterial infections and innovations in antibiotic therapy has never halted throughout human history. However, bacteria have evolved smartly and resistance against practically all conventional antibiotics has been developed. Furthermore, bacteria can form biofilms, which are surface-attached multicellular colonies. Biofilms shield bacteria against antibiotics and makes it harder to entirely eradicate infections . Under antibiotics stress, bacteria evolve into different phenotypes like hyper motile, hyper adherent and hyper virulent which are tolerant and persistent to antibiotic treatment. The use of antibiotic therapy to combat such resilient bacterial phenotypes is extremely tough. As a result, the scientific community is …


Uv- And Visible-Light Photopatterning Of Molecular Gradients Using The Thiol–Yne Click Reaction, Mark Mitmoen, Ofer Kedem Jul 2022

Uv- And Visible-Light Photopatterning Of Molecular Gradients Using The Thiol–Yne Click Reaction, Mark Mitmoen, Ofer Kedem

Chemistry Faculty Research and Publications

The rational design of chemical coatings is used to control surface interactions with small molecules, biomolecules, nanoparticles, and liquids as well as optical and other properties. Specifically, micropatterned surface coatings have been used in a wide variety of applications, including biosensing, cell growth assays, multiplexed biomolecule interaction arrays, and responsive surfaces. Here, a maskless photopatterning process is studied, using the photocatalyzed thiol–yne “click” reaction to create both binary and gradient patterns on thiolated surfaces. Nearly defect-free patterns are produced by first coating glass surfaces with mercaptopropylsilatrane, a silanizing agent that forms smoother self-assembled monolayers than the commonly used 3-mercaptopropyltrimethoxysilane. Photopatterning …


Properties And Behavior Of Tricarbonyl Manganese Scorpionate Complexes, Billy Shone Jul 2022

Properties And Behavior Of Tricarbonyl Manganese Scorpionate Complexes, Billy Shone

Master's Theses (2009 -)

Manganese tricarbonyl complexes have widely been studied for their ability to release carbon monoxide (CO) in the presence of light for potential applications in cancer therapy and in catalysis. Most studies focus on the kinetics and quantity of CO release and the overall impact on cell death. Far fewer studies identify the manganese intermediates and final products after decarbonylation. Identification of such products would be critical to improving reactivity and understanding potential (undesirable) side effects in future applications employing these CO releasing molecules (CORMs). Recently, nitrogen confused C-scorpionate ligands were introduced by the Gardinier group where a pyrazolyl ring is …


Improved Photodecarboxylation Properties In Zinc Photocages Constructed Using M‐Nitrophenylacetic Acid Variants, Austin K. Shigemoto, Avik Bhattacharjee, Erin E. Hickey, Hallee Jade Boyd, Theresa M. Mccormick, Shawn C. Burdette Jul 2022

Improved Photodecarboxylation Properties In Zinc Photocages Constructed Using M‐Nitrophenylacetic Acid Variants, Austin K. Shigemoto, Avik Bhattacharjee, Erin E. Hickey, Hallee Jade Boyd, Theresa M. Mccormick, Shawn C. Burdette

Chemistry Faculty Publications and Presentations

The methoxy- and fluoro-derivatives of meta-nitrophenylacetic acid (mNPA) chromophores undergo photodecarboxylation with comparable quantum yields to unsubstituted mNPA, but uncage at red-shifted excitation wavelengths. This observation prompted us to investigate DPAdeCageOMe (2-[bis(pyridin-2-ylmethyl)amino]-2-(4-methoxy-3-nitrophenyl)acetic acid) and DPAdeCageF (2-[bis(pyridin-2-ylmethyl)amino]-2-(4-fluoro-3-nitrophenyl)acetic acid) as Zn2+ photocages. DPAdeCageOMe has a high quantum yield and exhibits other photophysical properties comparable to XDPAdeCage ({bis[(2-pyridyl)methyl]amino}(9-oxo-2-xanthenyl) acetic acid), the best perforiming Zn2+ photocage reported to date. Since the synthesis of DPAdeCageOMe is more straightforward than XDPACage, the new photocage will be a highly competitive tool for biological applications.


A Protein-Based Therapeutic Combination For The Treatment Of Hard-To-Heal Wounds, Graham L. Strauss Jul 2022

A Protein-Based Therapeutic Combination For The Treatment Of Hard-To-Heal Wounds, Graham L. Strauss

USF Tampa Graduate Theses and Dissertations

Chronic wounds present many clinical challenges in relation to the successful treatment and closure of the damaged tissue. Most current treatment methods focused on one or two aspects to drive wound closure, while most chronic wounds are multifactorial environments with many of those dependencies relying on the termination of one another to effectively gain tissue construction, closure, and full skin thickness and composition. Natural wound healing processes allude to potential biologics that can impede the chronic breakdown of tissue, while restoring deposition of new tissue, and effectively leading to a healed wound. Proteases secreted by the body’s immune system lay …


Mechanisms And Impact Of Hypoxia Regulated Inhibins In Cancer, Ben Allen Horst Jul 2022

Mechanisms And Impact Of Hypoxia Regulated Inhibins In Cancer, Ben Allen Horst

Theses and Dissertations

Inhibins are heterodimeric ligands within the TGFβ superfamily, comprised of an α-subunit (INHA) and a β-subunit (either INHBA or INHBB) with emergent roles in cancer. Inhibins are biomarkers of disease burden and prognosis in a subset of cancers and utilize the coreceptors betaglycan (TGFBR3) and endoglin (ENG) for physiological or pathological outcomes. Previously, we found inhibin promotes angiogenesis in ovarian cancer however no mechanism of regulation for inhibin expression in cancer has been established. Hypoxia, a driver of tumor growth and metastasis, regulates angiogenic pathways that are targets for vessel normalization and ovarian cancer management. …


Evaluation Of The Energetic Factors In Crystalline Pharmaceuticals Using Solid-State Density Functional Theory And Low-Frequency Vibrational Spectroscopy, Margaret P. Davis Jul 2022

Evaluation Of The Energetic Factors In Crystalline Pharmaceuticals Using Solid-State Density Functional Theory And Low-Frequency Vibrational Spectroscopy, Margaret P. Davis

Dissertations - ALL

Due to the importance of maintaining stable and effective pharmaceutical solid doses, it is critical to study the variety of solid forms that active pharmaceutical ingredients can adopt including polymorphs, hydrates, and cocrystals. In this work, low-frequency vibrational spectroscopies and rigorous quantum mechanical simulations are combined to provide a new technique for characterizing and investigating pharmaceutically relevant polymorphs, hydrates, and cocrystals as well as a series of model cocrystals. Low-frequency spectra in the sub-200 cm-1 range provide not only unique and characteristic spectra for all of the systems explored here but, along with X-ray structural parameters, they offer a way …


Crystal Growth Of Inorganic Halides And Oxide-Halides For Scintillation Applications And Radiation Detection, Gyanendra B. Ayer Jul 2022

Crystal Growth Of Inorganic Halides And Oxide-Halides For Scintillation Applications And Radiation Detection, Gyanendra B. Ayer

Theses and Dissertations

Scintillators, materials which emit light when struck by high energy X-rays and y- rays, are extensively used in various fields including medical imaging, computed tomography, high-energy physics, and more recently in homeland security for the prevention of nuclear and radiological terrorism. While comparing with the traditional scintillators, which have long-term instability, high synthetic cost, toxicity, and hygroscopicity issues, metal halides have been reported to exhibit effective excitonic radioluminescence and greatly contribute in the field of scintillating applications and radiation detection. Currently, the mixed-anion oxide-fluorides have emerged as a prospective new class of scintillators, in which the mixed oxide-fluoride environment …


The Development Of A Monolithic Spatial Heterodyne Spectrometer For Extreme Environments, Arelis Michelle Colόn Jul 2022

The Development Of A Monolithic Spatial Heterodyne Spectrometer For Extreme Environments, Arelis Michelle Colόn

Theses and Dissertations

This work describes improvements to a novel instrument, the monolithic spatial heterodyne Raman spectrometer (mSHRS), which has potential to be utilized in space exploration and deep-ocean marine sensing. In previous work, the spatial heterodyne Raman spectrometer (SHRS) was demonstrated, as a small, high resolution, wide field of view spectrometer, originally developed for space applications where small size and compactness is a key consideration or where a wide field of view is advantageous, such as in remote spectroscopy. The spatial heterodyne spectrometer (SHS) was then later utilized for remote Laser-Induced Breakdown Spectroscopy (LIBS). The high throughput, high spectral resolution, and large …


Mass Spectrometric Investigation Of Removal/Transformation Of Emerging Contaminants For Safer Potable Wastewater Reuse, Kristin Cochran Jul 2022

Mass Spectrometric Investigation Of Removal/Transformation Of Emerging Contaminants For Safer Potable Wastewater Reuse, Kristin Cochran

Theses and Dissertations

Water scarcity is of increasing global concern as rising demand depletes current sources, so other sources such as potable wastewater reuse are being utilized. Advanced wastewater reuse removes pathogens and many contaminants, but there are concerns about resistant contaminants and the transformation products that are generated during the treatment process. This research focuses on several different contaminant classes, how well they are removed via advanced treatment processes, what transformation products arise from both advanced treatment and chlorination disinfection, and how those treated waters may impact health via toxicity and estrogen activity.

Contaminant classes considered are illicit drugs, pharmaceuticals such as …


Synthesis And Characterization Of Biomimetic Co And Fe Complexes With Trispyrazolylborate Ligands, Praveen Kumar Jul 2022

Synthesis And Characterization Of Biomimetic Co And Fe Complexes With Trispyrazolylborate Ligands, Praveen Kumar

Dissertations (1934 -)

Numerous reactions of biological and environmental significance are catalyzed by dioxygenases that incorporate both atoms of O2 into the substrate. These enzymes require a transition-metal cofactor for activity, typically a mononuclear nonheme iron center, although dioxygenases with first-row transition metal ions (Mn, Co, Ni) have been discovered. This dissertation focuses on synthetic studies based on mononuclear dioxygenases found in bacterial pathways for the breakdown and assimilation of inert organic compounds, including human-generated pollutants. Such enzymes are essential for bioremediation technologies used to restore contaminated soils and groundwaters. While crystallographic studies have revealed the active-site structures of various types of dioxygenases, …


Method Of Hybrid Control Based Of Dynamic Objects Of Neuro-Fuzzy Inference, Noilakhon Yakubova Jun 2022

Method Of Hybrid Control Based Of Dynamic Objects Of Neuro-Fuzzy Inference, Noilakhon Yakubova

Karakalpak Scientific Journal

The Results of interaction of the work is development of a method of control that allows simplifying, automating and unifying the process of design of the hybrid systems which are a basis of modern automation. To achieve a definite purpose, a method of control of a technical object based on the construction of an adaptive system of neuro-fuzzy inference is developed. The objects of the system of neuro-fuzzy inference are the classical and neuro-fuzzy models of control. Information exchange between models is provided by means of the developed hybrid control system. The result of the interaction of the two models …


Application Of A Synergetic Approach To The Problem Of Synthesizing An Intelligent Control System For Chemical Reactors, Komil Usmanov Jun 2022

Application Of A Synergetic Approach To The Problem Of Synthesizing An Intelligent Control System For Chemical Reactors, Komil Usmanov

Karakalpak Scientific Journal

The article deals with the synthesis of effective algorithms for controlling a chemical reactor and developed a intelligent synergistic controller for a class of indefinite nonlinear dynamic systems. A synergetic control scheme is proposed for solving the control problem for nonlinear systems. Non-linear systems with configurations and parameters that change over time require a completely non-linear model and adaptive control scheme for a practical operating environment. The synthesis of control laws is performed by the method of analytical design of aggregated controllers (ADAR).


Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev Jun 2022

Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev

Karakalpak Scientific Journal

This article describes how to design and implement a process for storing environmental information in a database using the Internet of Things. The problems that need to be solved with the help of this IoT system are the growing demand for forecasts in the world, the demand of the world market for a new sustainable method of implementing the digitization environment through the Internet of Things. The design was implemented using Arduino, Node-Red and sensors, selected when choosing a component based on the required parameters and sent to the database for monitoring and processing. A study of previous work and …


Theoretical Features Of Foreign Systems Of Preschool Education, Ayjamal Bazarbaeva Jun 2022

Theoretical Features Of Foreign Systems Of Preschool Education, Ayjamal Bazarbaeva

Karakalpak Scientific Journal

This article analyzes the features of preschool education systems in foreign countries. The positive experience and features of some systems are highlighted. Comparison of domestic and foreign systems of preschool education is carried out.


Mechanism Of Sila- And Germafluorenes For Biological Applications, Shelby Jarrett Jun 2022

Mechanism Of Sila- And Germafluorenes For Biological Applications, Shelby Jarrett

Dissertations

2,7-disubstituted silafluorenes and germafluorenes, originally designed for OLED applications, are a class of fluorescent dyes that have gained recent interest as probes for bioimaging and as biosensors to monitor cellular dynamics and interactions. Desirable biological probes absorb in the visible region, have high extinction coefficients, high quantum yield and excellent photostability. Here, their spectral properties are investigated under aqueous conditions for relevant biological applications. These molecules display intense blue fluorescence in the solid state and in solution, have high extinction coefficients, and exhibit appreciable solubility in aqueous solution. To better understand potential applications, the mechanism of fluorescence was investigated. It …


Table Of Contents Jun 2022

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Co-Microencapsulation Of Ruellia Tuberosa L. And Cosmos Caudatus K. Extracts For Pharmaceutical Applications, Choirin Annisa, Sasangka Prasetyawan, Anna Safitri Jun 2022

Co-Microencapsulation Of Ruellia Tuberosa L. And Cosmos Caudatus K. Extracts For Pharmaceutical Applications, Choirin Annisa, Sasangka Prasetyawan, Anna Safitri

Makara Journal of Science

This study aims to co-microencapsulate the Ruellia tuberosa L. and Cosmos caudatus K. extracts, with chitosan–sodium tripolyphosphate (Na-TPP) as coating material. α-Amylase inhibition and antioxidant assays were conducted to determine the potential of microcapsules used as antidiabetic agents. The microcapsules were manufactured under the influences of pH, Na-TPP concentration, and stirring time. The optimum microencapsulation conditions were selected based on the highest encapsulation efficiency. The optimum microencapsulation conditions were a pH of 4, Na-TPP concentration of 0.15% (w/v), and stirring time of 60 min. The microcapsules exhibited an IC50 (inhibitory concentration) value of 223.64 ± 0.81 µg/mL and an …


Preparation Of Zn/Al-Chitosan Composite For The Selective Adsorption Of Methylene Blue Dye In Water, Risfidian Mohadi, Patimah Mega Syah Bahar Nur Siregar, Neza Rahayu Palapa, Aldes Lesbani Jun 2022

Preparation Of Zn/Al-Chitosan Composite For The Selective Adsorption Of Methylene Blue Dye In Water, Risfidian Mohadi, Patimah Mega Syah Bahar Nur Siregar, Neza Rahayu Palapa, Aldes Lesbani

Makara Journal of Science

Layered double hydroxide (LDHs) are widely used adsorbents for methylene blue removal. However, LDHs have a perishable structure that cannot be used repeatedly. Modifying LDHs with chitosan produces a strong material with a large surface area for methylene blue adsorption. Adsorption conditions were optimized by determining the adsorption isotherms and the adsorbent regeneration process. Results showed that the adsorption process was balanced in 90 min with maximum adsorption capacities of 86.207 mg/g, 35.336 mg/g, and 98.039 mg/g for Zn/Al, chitosan, and Zn/Al-chitosan, respectively. The adsorption in this study followed the Freundlich isotherm model. Regeneration analysis of the adsorbent showed that …