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Kansas Forest Service Annual Report 2020
No full textThis publication is an annual report of the services provided and a summary of the 2020 Kansas Forest Service's operating year
Evaluation of the Remaining Prestress Force and Center Negative Capacity of Ties Removed from Track after 25 Years
Get PDFA study was conducted to determine the amount of internal prestress force remaining in prestressed concrete railroad tie designs that have withstood a lifetime of service without problems. Twelve (12) different tie designs that had performed well in track for over 25 years with no signs of longitudinal splitting were evaluated. Four different experimental test methods were used to determine the remaining prestress force in these existing ties. These included the flexural crack reopening method, the newly developed direct tension method, the strain gage method, and measurement of the length change of wires extracted from the ties. Test results indicate that the direct tension test was the most accurate of the four methods, and that existing ties tended to have prestressing forces in the range of 82-93 kips
Design of functional polymeric materials for cancer-targeted drug delivery and cellular capture and isolation
Get PDFDoctor of PhilosophyDepartment of Chemical EngineeringJennifer L. AnthonyRyan R. HansenSynthetic polymeric materials offer many exciting advantages with the plethora of functionalization techniques affording materials with unique properties, multiple functionalities, and elaborate architectures for a variety of applications. In the drug delivery field, the use of synthetic polymers as nano-sized drug carriers in cancer nanomedicine has gained tremendous interest as an alternative to conventional small molecule anticancer drugs to reduce drug-related toxicity and increase targetability. Like other nanocarriers, synthetic polymeric nanocarriers rely on passive-drug targeting, also known as the Enhanced Permeability and Retention (EPR) effect in leaky tumor vasculature for delivery of therapeutics. The biological complexity and barriers that exist in the body however have proven to be a huge challenge in selectively delivering therapeutics to cancer cells. Synthetic polymers also offer significant advantages for improved isolation and characterization of microbes attached to surfaces compared to conventional techniques. However, the retrieval of microbes from synthetic polymer interfaces with high spatial precision without damaging the underlying live bacterial cells remains a critical challenge for further characterization. Therefore, the goal of this dissertation is to explore and develop synthetic, functional, stimulus-responsive polymeric interfaces (polymeric micelles, photodegradable hydrogels) for targeted drug delivery to cancer cells and improved isolation of microbes for molecular characterization.
The majority of this thesis (chapters 2, 3, and 4) focuses on utilizing the intrinsic properties present in tumor microenvironments (TME), mainly elevated levels of reactive oxygen species (ROS) and overproduction of matrix metalloproteinase-2 (MMP-2) enzyme for the design and synthesis of stimuli-sensitive synthetic block copolymer polymeric micelles (BCPMs) by reversible addition-fragmentation chain transfer (RAFT) polymerization for targeted delivery of therapeutics to cancer cells. The synthesized BCPMs were extensively studied and evaluated for their chemistry and biological functions in in vitro cancer therapy. In chapter 2, the conventional chemotherapeutic drug, Doxorubicin (DOX) was loaded physically into the hydrophobic core of BCPMs bearing a library of oxidation-sensitive thioether groups. Results showed that the micelles, especially micelles with intermediate ROS sensitivity, significantly increased toxicity of DOX in liver cancer cells (HepG2) but protected normal cells, human umbilical endothelial cells (HUVECs) from DOX cytotoxicity. Taking it a step further, in chapter 3, hydrogen sulfide (H₂S) prodrug (ADT) was chemically conjugated to the core of BCPMs bearing oxidation-sensitive thioether group and the anti-cancer effects of H₂S in colon cancer cells (HT29) were evaluated. A greater anti-proliferative effect was observed in HT29 cells with no significant toxicity in HUVEC cells. In chapter 4, a different approach was taken where BCPM bearing MMP-2 enzyme cleavable peptide motifs and chemically conjugated ADT was designed for site-specific delivery of H₂S to cancer cells. The greater release of H₂S from MMP-2 sensitive micelles exhibited stronger anti-proliferative activity in HT29 cells. The final portion of this thesis (chapter 5) focuses on the development of the polymer surface dissection (PSD) method which uses biofunctionalized, photodegradable polyethylene glycol (PEG)-based hydrogels for the isolation of microbes from polyvinylidene difluoride wastewater membrane surfaces. The flocs were extracted with high spatial precision and minimal DNA damage after exposure to spatiotemporally controlled ultraviolet (UV) light using a patterned illumination tool, allowing for follow-up characterization by 16S rRNA sequencing. The technique allows for the identification of microbes that form small flocs on membrane surfaces without requiring a culture step for enrichment, and will be used in future work to identify communities of microorganisms that initiate membrane biofilms in bio-separation processes
Perceptions of faculty members on the value of distance education at two different types of institutions of higher education in the Kingdom of Saudi Arabia
Get PDFDoctor of PhilosophyDepartment of Curriculum and InstructionJ. Spencer ClarkWith the current rapid and forced adoption of online teaching during COVID-19 pandemic in many parts of the globe, the need for more studies for the burden faculty members will face to improve online learning will increase. This study aimed to examine the perceptions of faculty in Qassim University (QU) and Princess Nourah University (PNU) in Saudi Arabia toward distance education. For this purpose, the quantitative approach was used using an online survey instrument, quantitative data were collected from 122 faculty members. Findings of this study may encourage administrators in the KSA’s higher education institutions to make key policy and process decisions that focus on improving the quality of online teaching. Understanding the influence (positive or negative) of faculty perceptions on online learning can help inform their decisions.
The sample of the study consisted of 122 faculty members of faculty in Qassim University (QU) and Princess Nourah University (PNU) in Saudi Arabia. Findings from this particular study at both Universities have shown promising evidence that faculty members had a positive attitude toward online courses to some extent. The findings failed to support the null hypothesis of no difference for perceived value of distance education, and institutional support of online education regarding the influence of institutional support of online education on faculty perceptions of distance education. The results indicated that as length of institutional support of online education increases, satisfaction with effectiveness of online learning also increases. Faculty perceived value of distance education were also found to be related to the individual’s perceptions of distance education. As the perceived value of distance education were more positive, so too does satisfaction with effectiveness of online learning. Theoretically, the findings of the current study are in concert with earlier research by Herzberg (1985) whose two-factor theory attributed increased responsibility advancement, and achievement to satisfaction
Futures so bright, we have to wear shades 2020 - 2021 Kansas Pride Review
No full textSummary of the 2020-2021 actiivities of the Kansas PRIDE program and affiliated communities
Report of Progress 1159
Get PDFCorn performance tests, conducted annually by the Kansas Agricultural Experiment Station, provide farmers, extension workers, and seed industry personnel with unbiased agronomic information on many of the corn hybrids marketed in the state. Because entry selection and location are voluntary, not all hybrids grown in the state are included in tests, and the same group of hybrids is not grown uniformly at all test locations
Enhancing high-order harmonic generation by controlling the diffusion of the electron wave packet
Get PDFWe experimentally study the enhancement of high-order harmonic generation (HHG) driven by synthesized ω−3ω laser fields, where we control whether the ionization rate or the electron wave packet’s diffusion is the dominant enhancement mechanism. When minimizing the electron wave packet’s diffusion, the excursion times of the corresponding electron trajectories are reduced by a factor of 2 or more. This result is important for imaging techniques that use the returning electron wave packet to probe the remaining ion. Furthermore, we achieve a 10× to 3800× enhancement of the harmonic yield driven by the bichromatic fields relative to that of an optimized single-color field, showing that the bichromatic fields improve HHG’s capability as a light source. We also measure that the two-color field’s harmonics have half the divergence angle compared to their single-color counterpart, suggesting that the “short” electron trajectories play a more prominent role compared to their “long” trajectory counterparts, thus improving the wavefront of the emerging harmonic beam
High Resolution 3D Optical Scanning of Crossties to Assess Cross-Sectional Parameters and the Effects of Long-Term Abrasion and Wear
Get PDFThis report documents measurement of the 3D geometrical properties associated with prestressed concrete railroad ties that have been subject to long-term in-track loading. A commercially-available 3D laser-based optical scanning system was used to scan the surface of sampled in-service crossties to a spatial resolution of about 1-mm, resulting in a 3D solid body CAD model of each scanned tie. A high-speed algorithm was developed to process the detailed cross-section geometrical parameters to an axial resolution of 0.5 inches, achieving an overall processing time of only a few minutes. The agreement between the ideal CAD model cross-section parameters and the measured (scanned) parameters was found to be excellent. Measured crosstie cross-sectional parameters used in support of on-going FRA project work included cross-sectional area, area moment of inertia, neutral axis position, eccentricity, and shape factor
A Wire Indent Profiling System for the Assessment of Bond and Splitting Propensity of Prestressing Wires Used in Pretensioned Concrete Railroad Ties
Get PDFThe focus of this research was the creation of an automatic non-contact laser-based indent profiling system for the purpose of rapidly assessing geometrical characteristics of indented wires used in the manufacture of pretensioned concrete railroad ties. The process of measuring indent geometrical characteristics by traditional means is a time-consuming process which severely limits the frequency of testing and prevents statistically relevant sample sizes. In parallel with concrete prism transfer length and splitting propensity testing conducted in conjunction with this project, this system was used to identify which indent characteristics were directly related to both bond and splitting propensity in pretensioned concrete ties. This report details the automation of this indent profiling system and the results obtained for many different indented wires that were currently or historically used to manufacture pretensioned concrete railroad ties
First Time Detection Of Brome Mosaic Virus Associated With Other Wheat Viruses In Kansas Wheat Using Nanopore Sequencing
Get PDFKansas wheat production has been threatened by Wheat streak mosaic complex of three viruses including Wheat streak mosaic virus (WSMV). Triticum mosaic virus (TriMV), and High Plains wheat mosaic emaravirus (HPWMOV).
In 2017. Kansas wheat producers lost 19.2 million bushels of wheat worth $76.8 million due to wheat streak mosaic.
Infection of a single plant with multiple viruses is common in wheat fields. Other common wheat viruses have been recorded from Kansas but not the Brome mosaic virus (BMV)
Diagnosis of virus like symptoms in plants has been mostly dominated by targeted-specific methods with known antibodies, primers, and probes.
These targeted methods identify only already known viruses and virus combinations Next generation sequencing techniques such a Nanopore sequencing technology has great potential for identifying novel and multiple potential plant pathogens in a single analysis.
Reliable diagnostic methods are needed to identify the risks in plant health to develop appropriate plant protection strategies