The Clusterin (CLU) gene, also known as apolipoprotein J (ApoJ), is currently the third most associated late-onset Alzheimer's disease (LOAD) risk gene. However, little was known about the possible effect of CLU genetic variants on AD pathology in brain. Here, we evaluated the interaction between 7 CLU SNPs (covering 95% of genetic variations) and the role of CLU in β-amyloid (Aβ) deposition, AD-related structure atrophy, abnormal glucose metabolism on neuroimaging and CSF markers to clarify the possible approach by that CLU impacts AD. Finally, four loci (rs11136000, rs1532278, rs2279590, rs7982) showed significant associations with the Aβ deposition at the baseline level while genotypes of rs9331888 (P = 0.042) increased Aβ deposition. Besides, rs9331888 was significantly associated with baseline volume of left hippocampus (P = 0.014). We then further validated the association with Aβ deposition in the AD, mild cognitive impairment (MCI), normal control (NC) sub-groups. The results in sub-groups confirmed the association between CLU genotypes and Aβ deposition further. Our findings revealed that CLU genotypes could probably modulate the cerebral the Aβ loads on imaging and volume of hippocampus. These findings raise the possibility that the biological effects of CLU may be relatively confined to neuroimaging trait and hence may offer clues to AD.

Phosphatidylinositolbinding clathrin assembly protein (PICALM) gene is one novel genetic player associated with late-onset Alzheimer's disease (LOAD), based on recent genome wide association studies (GWAS). However, how it affects AD occurrence is still unknown. Brain reserve hypothesis highlights the tolerant capacities of brain as a passive means to fight against neurodegenerations. Here, we took the baseline volume and/or thickness of LOAD-associated brain regions as proxies of brain reserve capacities and investigated whether PICALM genetic variations can influence the baseline reserve capacities and the longitudinal atrophy rate of these specific regions using data from Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset. In mixed population, we found that brain region significantly affected by PICALM genetic variations was majorly restricted to posterior cingulate. In sub-population analysis, we found that one PICALM variation (C allele of rs642949) was associated with larger baseline thickness of posterior cingulate in health. We found seven variations in health and two variations (rs543293 and rs592297) in individuals with mild cognitive impairment were associated with slower atrophy rate of posterior cingulate. Our study provided preliminary evidences supporting that PICALM variations render protections by facilitating reserve capacities of posterior cingulate in non-demented elderly.

The cooperative emission of interacting nanocrystals is an exciting topic fueled by recent reports of superfluorescence and superradiance in assemblies of perovskite nanocubes. Several studies estimated that coherent coupling is localized to a small fraction of nanocrystals (10-7-10-3) within the assembly, raising questions about the origins of localization and ways to overcome it. In this work, we examine single-excitation superradiance by calculating radiative decays and the distribution of superradiant wave function in two-dimensional CsPbBr3 nanocube superlattices. The calculations reveal that the energy disorder caused by size distribution and large interparticle separations reduces radiative coupling and leads to the excitation localization, with the energy disorder being the dominant factor. The single-excitation model clearly predicts that, in the pursuit of cooperative effects, having identical nanocubes in the superlattice is more important than achieving a perfect spatial order. The monolayers of large CsPbBr3 nanocubes (LNC = 10-20 nm) are proposed as model systems for experimental tests of superradiance under conditions of non-negligible size dispersion, while small nanocubes (LNC = 5-10 nm) are preferred for realizing the Dicke state under ideal conditions.

This dichotomous key featuring images and facts was created to help students easily identify some of the ant species found in and around UCSB's North Campus Open Space but can be used by anyone in the region where these 10 species are distributed.

When the winds of change blow and the oceans churn in acquiescence, El Nino can leave a trail of destruction across the Pacific Ocean and beyond. It is a climate phenomenon that impacts lives, livelihoods and biodiversity all around the world, and its wide-ranging impact illustrates clearly the interconnectedness of the global climate system. And if El Nino, a natural event, can cause such devastation, what more harm can human-driven climate change cause? These thoughts eventually led me to develop this Capstone project, focusing on climate communication through the lens of El Nino. Awareness is, after all, the first step toward climate action. And as a journalist, it is my job to help raise this awareness, and draw links between how climate science can inform policy and save lives. For this project, I traced the footsteps of El Nino across the Pacific Ocean, interviewing people and policy-makers living in places where the impacts of El Nino are hardest felt. Some shared stories of love and loss. Others spoke of hope, and ways of safeguarding lives and species from the harshest impacts of climate change. In this publication, Straits Times photojournalist Mark Cheong and I bring you their stories from Indonesia and the Galapagos Islands, two archipelagos across the Pacific Ocean that are hard hit by the impacts of El Nino. It is our hope that these tales would prompt you to think more about global climate change, and the individual’s role in bending the emissions curve.

The focus of this dissertation is on the fundamental capacity bounds of wireless ad hoc networks. We establish upper and lower bounds on the capacity to shed light on what is theoretically possible and what is currently achievable. In the first part of the dissertation, we introduce and describe a method to find an upper bound on the capacity of wireless networks with arbitrary topology, size and traffic demands. The upper bound not only provides a yardstick against which the throughput of an existing wireless ad hoc network scheme can be gauged, it also provides insight into how to design better routing and medium access control protocols for wireless networks. Using the upper bound, we examine the behavior of networks of different size, under different channel conditions, and with different traffic patterns. Numeric results indicate that, when the channel conditions are known precisely, shadow and multipath fading increase capacity; and that the capacity increases with network size when full traffic patterns are considered but decreases when directional traffic patterns are considered. In the second part, we obtain the performance of an optimistic protocol based on CSMA/CA and compare it against the upper bound. There is a significant gap between the two results, especially when considering large networks operating in the high SNR region. In the third part, we describe a new time-division scheduling scheme derived from the upper bound. In addition, we make an improvement to the schedules that increases the capacity significantly, even for small to medium size networks. Our schedules perform better than the protocol based on CSMA/CA, for medium to high SNR regions. Moreover, they also perform well against the upper bound when there is a directional traffic pattern, but not as well when there is a full traffic pattern. Finally, we examine the effects of time-varying fading and mobility on the schedules. We conclude that our schedules perform well in an environment where the channel changes slowly relative to the schedule update rate

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.

This dichotomous key featuring images and facts was created to help students easily identify some of the bee species found in and around UCSB's North Campus Open Space but can be used by anyone in the region where these 10 species are distributed.