University of California

About: University of California is a education organization based out in Oakland, California, United States. It is known for research contribution in the topics: Population & Layer (electronics). The organization has 55175 authors who have published 52933 publications receiving 1491169 citations. The organization is also known as: UC & University of California System.

Apolipoprotein E: from cardiovascular disease to neurodegenerative disorders

Abstract: Apolipoprotein (apo) E was initially described as a lipid transport protein and major ligand for low density lipoprotein (LDL) receptors with a role in cholesterol metabolism and cardiovascular disease. It has since emerged as a major risk factor (causative gene) for Alzheimer’s disease and other neurodegenerative disorders. Detailed understanding of the structural features of the three isoforms (apoE2, apoE3, and apoE4), which differ by only a single amino acid interchange, has elucidated their unique functions. ApoE2 and apoE4 increase the risk for heart disease: apoE2 increases atherogenic lipoprotein levels (it binds poorly to LDL receptors), and apoE4 increases LDL levels (it binds preferentially to triglyceride-rich, very low density lipoproteins, leading to downregulation of LDL receptors). ApoE4 also increases the risk for neurodegenerative diseases, decreases their age of onset, or alters their progression. ApoE4 likely causes neurodegeneration secondary to its abnormal structure, caused by an interaction between its carboxyl- and amino-terminal domains, called domain interaction. When neurons are stressed or injured, they synthesize apoE to redistribute cholesterol for neuronal repair or remodeling. However, because of its altered structure, neuronal apoE4 undergoes neuron-specific proteolysis, generating neurotoxic fragments (12–29 kDa) that escape the secretory pathway and cause mitochondrial dysfunction and cytoskeletal alterations, including tau phosphorylation. ApoE4-associated pathology can be prevented by small-molecule structure correctors that block domain interaction by converting apoE4 to a molecule that resembles apoE3 both structurally and functionally. Structure correctors are a potential therapeutic approach to reduce apoE4 pathology in both cardiovascular and neurological disorders.

Recent Developments in Deterministic Sequencing and Scheduling: A Survey

Abstract: The theory of deterministic sequencing and scheduling has expanded rapidly during the past years. We survey the state of the art with respect to optimization and approximation algorithms and interpret these in terms of computational complexity theory. Special cases considered are single machine scheduling, identical, uniform and unrelated parallel machine scheduling, and open shop, flow shop and job shop scheduling. This paper is a revised version of the survey by Graham et al. (Ann. Discrete Math. 5(1979) 287–326) , with emphasis on recent developments.

A Sharp Condition for Scattering of the Radial 3D Cubic Nonlinear Schrödinger Equation

Abstract: We consider the problem of identifying sharp criteria under which radial H1 (finite energy) solutions to the focusing 3d cubic nonlinear Schrodinger equation (NLS) i∂tu + Δu + |u|2u = 0 scatter, i.e., approach the solution to a linear Schrodinger equation as t → ±∞. The criteria is expressed in terms of the scale-invariant quantities \({\|u_0\|_{L^2}\| abla u_0\|_{L^2}}\) and M[u]E[u], where u0 denotes the initial data, and M[u] and E[u] denote the (conserved in time) mass and energy of the corresponding solution u(t). The focusing NLS possesses a soliton solution eitQ(x), where Q is the ground-state solution to a nonlinear elliptic equation, and we prove that if M[u]E[u] \|Q\|_{L^2}\| abla Q\|_{L^2}}\), then the solution blows-up in finite time. The technique employed is parallel to that employed by Kenig-Merle [17] in their study of the energy-critical NLS.

Immigration and the Imagined Community in Europe and the United States

Abstract: Both Europe and the United States are confronting the challenges of economic and cultural integration posed by immigration. This article uses the ESS and CID surveys to compare transatlantic public opinion about immigrants and immigration. We find more tolerance for cultural diversity in the United States, but we also find that Americans, like Europeans, tend to overestimate the number of immigrants in their countries and tend to favor lower levels of immigration. The underpinnings of individual attitudes are similar in all countries and immigration attitudes are surprisingly unrelated to country-level differences in GDP, unemployment and the number and composition of the foreign born. An implication of these findings is that acceptance of higher levels of immigration, deemed by many to be an economic need, will require both more selective immigration policies and an emphasis on the cultural assimilation of newcomers.

Decoherence-Free Subspaces and Subsystems

Abstract: Decoherence is the phenomenon of non-unitary dynamics that arises as a consequence of coupling between a system and its environment. It has important harmful implications for quantum information processing, and various solutions to the problem have been proposed. Here we provide a detailed a review of the theory of decoherence-free subspaces and subsystems, focusing on their usefulness for preservation of quantum information.