Improving Freezing Tolerance of Cold-Sensitive Grape Cultivars Using Abscisic Acid

Thanks to my advisor Dr. Imed Dami, my SAC members: Dr. Michelle Jones and Dr. Joshua Blakeslee. Thanks for the support from all my previous and current lab mates.Grape and wine industries in colder regions such as Ohio have been expanding rapidly and demand for premium wine grapes has also increased. However, several popular cultivars are sensitive to freezing temperatures below -20°C. The goal of this study was to improve freezing tolerance of sensitive grape cultivars using abscisic acid (ABA). The objectives of this research are to: 1) evaluate the response of greenhouse- and field-grown wine grape cultivars to exogenous ABA, 2) characterize the changes of freezing tolerance, water content, and soluble sugars in bud tissues of greenhouse- and field-grown vines in response to exogenous ABA. In the field, we evaluated the effect of exogenous ABA on freezing tolerance and optimum timing of ABA application of Vitis vinifera ‘Pinot gris’. ‘Pinot gris’ grapevines were treated with 400mg/L ABA at different stages of development (veraison, post-veraison and post-harvest). The application of ABA did not affect yield components or fruit composition, but caused early leaf abscission, advanced bud dormancy, decreased bud water content, and eventually increased freezing tolerance. Greenhouse experiments showed that ABA caused desiccation of buds which was associated with increased freezing tolerance. Ultimately, the findings of this project are valuable to grape producers to provide another tool for freeze protection and to the scientific community for better understanding of the mechanisms of freezing tolerance.SCRI ProjectOhio Grape Industries ProgramDepartment of Horticulture & Crop Science, OARDC, OS

Friedmann's Equations in All Dimensions and Chebyshev's Theorem

This short but systematic work demonstrates a link between Chebyshev's theorem and the explicit integration in cosmological time $t$ and conformal time $\eta$ of the Friedmann equations in all dimensions and with an arbitrary cosmological constant $\Lambda$. More precisely, it is shown that for spatially flat universes an explicit integration in $t$ may always be carried out, and that, in the non-flat situation and when $\Lambda$ is zero and the ratio $w$ of the pressure and energy density in the barotropic equation of state of the perfect-fluid universe is rational, an explicit integration may be carried out if and only if the dimension $n$ of space and $w$ obey some specific relations among an infinite family. The situation for explicit integration in $\eta$ is complementary to that in $t$. More precisely, it is shown in the flat-universe case with $\Lambda\neq0$ that an explicit integration in $\eta$ can be carried out if and only if $w$ and $n$ obey similar relations among a well-defined family which we specify, and that, when $\Lambda=0$, an explicit integration can always be carried out whether the space is flat, closed, or open. We also show that our method may be used to study more realistic cosmological situations when the equation of state is nonlinear.Comment: Extended and re-organized version to appear in JCA

How to Motivate Engineering Education Faculty for Instructional Innovation: The Digital Leadership Effectiveness Test

Faculty instructional innovation is the driving force behind engineering education reform and an important guarantee to promote the modernization of engineering education. With the advent of the digital era, digital leadership has become a key factor in encouraging faculty instructional innovation. Therefore, based on resource conservation theory and social cognition theory, this study explores the relationship between digital leadership, digital self-efficacy, and engineering education faculty instructional innovation and analyzes the mediating role of digital self-efficacy. Through the analysis of 316 valid samples, the results show that digital leadership and digital self-efficacy have a significant positive impact on engineering education faculty instructional innovation. Digital leadership also has a significant positive impact on digital self-efficacy, and digital self-efficacy plays a mediating role in the effect of digital leadership on engineering education faculty instructional innovation. This study reveals the impact and mechanism of digital leadership on engineering education faculty instructional innovation and provides empirical support for improving faculty instructional innovation in engineering education

Convenient Production of Photothermal Recycling Phosphorescent Materials from Cellulose and Lignin

Developing recyclable room-temperature phosphorescent (RTP) films using ultrafast fabrication techniques remains a critical yet challenging objective. With this research, we developed an RTP film (Cell-Lig) through ethanol-induced phase transition, achieving solid film formation within 1 s from ionic liquid (1-butyl-3-methylimidazolium chloride, [Bmim]Cl) solutions of cellulose and lignin. The phase transition also generated a confined rigid environment for Cell-Lig, activating thickness- and temperature-dependent green RTP emission from the incorporated lignin. Furthermore, red afterglow emission using an energy transfer mechanism was realized by incorporating rhodamine B (RhB). The inherent photothermal activity of lignin endowed Cell-Lig with easy recyclability using light-controlled phase transitions. Under irradiation, photothermal evaporation of residual ethanol triggered liquefaction (solid-to-liquid transition), while ethanol reintroduction facilitated instantaneous hardening. Remarkably, the initial RTP performance was maintained over six recycling cycles. Capitalizing on these attributes, Cell-Lig was successfully used for advanced coating and security applications.</p

Sustainable Afterglow Room-Temperature Phosphorescence Emission Materials Generated Using Natural Phenolics

Long-lived afterglow room-temperature phosphorescence (RTP) from natural phenolics has seldom been reported yet this is essential for the development of sustainable afterglow RTP materials. With this research, we have prepared sustainable afterglow RTP materials (GA@SA) with a lifetime of up to ≈934.7 ms by embedding gallic acid (GA) within a Ca2+-crosslinked sodium alginate (SA) matrix. Theoretical simulations indicate that the restricted carbonyl moieties of the GA and H-type aggregates of GA in a SA matrix promoted the spin orbit coupling (SOC) of GA and induced afterglow emission. Moreover, afterglow RTP emission could be produced by embedding different types of natural phenolics such as, tannic acid, caffeic acid and chlorogenic acid into Ca2+-crosslinked networks of SA. As an illustration of potential applications, GA@SA was used to prepare anti-counterfeit afterglow clothing and paper. This work provides an innovative method for the activation of long-lived afterglow RTP from sustainable phenolics.</p

“All-in-one” carbon dots-based catalyst for converting CO2 to cyclic carbonates

Converting CO 2 with various epoxides to cyclic carbonates is extremely important. However, most of catalysts for such conversion either require complicated fabrication or are obtained from unsustainable sources. Motivated by this problem, we prepare biomass-based “all-in-one” carbon dots as nano-organocatalysts for firstly converting CO 2 to cyclic carbonates. In this work, carbon dots (CD@KI) with high catalytic performance and good recyclability are prepared from sodium phytate (SP), polyethylenimine (PEI) and KI using one-pot hydrothermal treatment featuring cheap precursors and simple operation. Assisted by highly catalytic activity of CD@KI, up to 99.5% yield is achieved for converting CO 2 and various epoxides to cyclic carbonates under mild conditions (solvent-free and 1 atm of CO 2). Moreover, the conversion yield is maintained for reactions up to 10 g in scale. Significantly, by taking advantage of the inherent luminescence of CD@KI, the as-formed cyclic carbonates catalysed by CD@KI can be directly converted to afterglow polymer composites.</p

Vibration Suppression of a 3-DOF Parallel Manipulator Based on Hybrid Negative Impulses Multi-mode Input Shaping

Abstract. The classic multi-mode negative impulses input shapers can suppress the residual vibration of the multi-mode system effectively. But when these several frequencies bandwidths and amplitudes of vibration modes are greatly different, the time delay and the suppression performances of input shapers are decreased. However, the hybrid multi-mode negative impulses input shapers can overcome the disadvantage. The hybrid double-mode negative impulses input shapers of a 3-DOF parallel manipulator and are constructed and compared with the classic multi-mode negative impulses input shapers. And the numerical simulations are shown out, for different frequencies bandwidths and amplitudes of vibration, and the hybrid multi-mode negative impulses input shapers can increase the total suppression performance of input shaper

Earthquake Trauma, Overgeneral Autobiographical Memory, and Depression Among Adolescent Survivors of the Wenchuan Earthquake

Trauma has a profound impact on overgeneral autobiographical memory (OGM), which is a risk factor for depression. Violent earthquakes can cause tremendous trauma in survivors. We examined the relationship between earthquake trauma, OGM and depression in adolescent survivors of the Wenchuan earthquake in this study. OGM was assessed using the autobiographical memory test in a sample of adolescent participants who experienced the violent earthquakes in Wenchuan, China, in 2008 and control participants who had never experienced a destructive earthquake. Depression was measured using the Beck Depression Inventory-II in all participants. The results showed that compared with the adolescents with no earthquake trauma, the adolescents with earthquake trauma reported significantly more depression (d = 0.49) and overgeneral autobiographical memories (d = 0.55). Moreover, when they experienced earthquake trauma, the adolescents with low OGM did not experience more depression, but the adolescents with average and high OGM experienced more depression than the adolescents with no earthquake trauma. This finding indicated that in a non-Western cultural context, adolescents’ propensity toward OGM made them vulnerable to depression after experiencing an earthquake trauma