Consumer Behavior toward Luxury Fashion Rental: A Hierarchical Motivations Approach

With the emerging New Luxury Comers and new consumerism after the recession, luxury fashion rental has been showing a great potential for speed growth. However, limited literature is existing on consumer behavior toward luxury fashion rental. Using a hierarchical Confirmatory Factor Analysis, this study conceptualized the multi-dimensional structure of consumers’ motivations toward luxury fashion rentals. Seven motivations were identified and classified as intrinsic vs. extrinsic. The results of this study can provide a great foundation for future studies on consumers’ behavior toward luxury fashion rental services

Hybrid adaptive sequential sampling for reliability-based design optimization

To reduce the cost for reliability analysis and optimization of complex engineering systems, surrogate models can be used to replace expensive physical models. One of the critical tasks of employing surrogate models for system design optimization is to develop an accurate surrogate model cost-effectively. In this thesis, a new hybrid adaptive sequential sampling strategy has been developed to substantially improve the efficiency of the surrogate model development process. The developed sampling strategy combines local sampling that focuses on regional model fidelity improvements with global sampling that ensures effective design updates in the design optimization process. Specifically, a confidence-guided sequential sampling scheme is developed for local sampling, which identifies most useful sample points along the descending direction of the objective function as well as the constraints to improve the regional model fidelity. Similarly, a constraint boundary sampling scheme is adopted for the global sampling purpose, which efficiently locates the constraint boundaries and balances the efforts devoted to global sampling and local sampling processes. The efficacy of the developed hybrid adaptive sequential sampling technique for reliability-based design optimization using surrogate models is assessed with several numerical case studies, through comparisons with existing approaches that have been reported in the literature. The case study results have demonstrated that the developed new sampling strategy can significantly reduce the number of sample points required in updating the surrogate model along with the design optimization process. By using the developed adaptive sequential sampling strategy for surrogate modeling, the design processes become more efficient and cost-effective

All-Optical Ultrafast Control and Read-Out of a Single Negatively Charged Self-Assembled InAs Quantum Dot

We demonstrate the all-optical ultrafast manipulation and read-out of optical transitions in a single negatively charged self-assembled InAs quantum dot, an important step towards ultrafast control of the resident spin. Experiments performed at zero magnetic field show the excitation and decay of the trion (negatively charged exciton) as well as Rabi oscillations between the electron and trion states. Application of a DC magnetic field perpendicular to the growth axis of the dot enables observation of a complex quantum beat structure produced by independent precession of the ground state electron and the excited state heavy hole spins

The C. elegans PUM1, 2-like RNA binding protein PUF-8 is required for robustness of the cell death fate

During C. elegans development, 1090 somatic cells are generated of which 959 survive and 131 die, many through apoptosis. We present evidence that PUF-8, a C. elegans ortholog of the mammalian RNA binding proteins PUM1 and PUM2, is required for the robustness of this 'survival and death' pattern. We found that PUF-8 prevents the inappropriate death of cells that normally survive, and we present evidence that this anti-apoptotic activity of PUF-8 is dependent on PUF-8's ability to interact with ced-3caspase mRNA thereby repressing the activity of the pro-apoptotic ced-3caspase gene. PUF-8 also promotes the death of cells that are programmed to die, and we propose that this pro-apoptotic activity of PUF-8 may depend on PUF-8's ability to repress the expression of the anti-apoptotic ced-9Bcl-2 gene. Our results suggest that stochastic differences in the expression of genes within the apoptosis pathway can disrupt the highly reproducible and robust survival and death pattern during C. elegans development, and that PUF-8PUM1, 2 acts at the post-transcriptional level to level out these differences, thereby ensuring proper cell number homeostasis

Strengthening and weakening of methane hydrate by water vacancies

Gas clathrate hydrates show promising applications in sustainable technologies such as future energy resources, gas capture and storage. The stability of clathrate hydrates under external load is of great crucial to those important applications, but remains unknown. Water vacancy is a common structural defect in clathrate hydrates. Herein, the mechanical characteristics of sI methane hydrates containing three types of water vacancy are investigated by molecular dynamics simulations with four different water forcefields. Mechanical properties of methane hydrates such as tensile strength are dictated not only by the density but also the type of water vacancy. Surprisingly, the tensile strength of methane hydrates can be weakened or strengthened, depending on the adopted water model and water vacancy density. Strength enhancement mainly results from the formation of new water cages. This work provides critical insights into the mechanics and microstructural properties of methane clathrate hydrates under external load, which is of primary importance in the recovery of natural gas from methane hydrate reservoirs.Cited as: Lin, Y., Liu, Y., Xu, K., Li, T., Zhang, Z., Wu, J. Strengthening and weakening of methane hydrate by water vacancies. Advances in Geo-Energy Research, 2022, 6(1): 23-37. https://doi.org/10.46690/ager.2022.01.0