Secondary Grating Formation by Readout at Bragg-null Incidence

We show that when a dynamic hologram is read out by illumination at the Bragg nulls of a previously recorded grating the diffracted beam inside the medium can result in the recording of two secondary gratings that alter the final selectivity curve. This is confirmed experimentally. This effect can cause cross talk in hologram multiplexing that is stronger than interpage cross talk when a small number of holograms with high diffraction efficiencies are multiplexed

Simple Modifications of Branched PEI Lead to Highly Efficient siRNA Carriers with Low Toxicity

Polymer carriers like PEI which proved their efficiency in DNA delivery were found to be far less effective for the applications with siRNA. In the current study, we generated a number of nontoxic derivates of branched PEI through modification of amines by ethyl acrylate, acetylation of primary amines, or introduction of negatively charged propionic acid or succinic acid groups to the polymer structure. The resulting products showed high efficiency in siRNA-mediated knockdown of target gene. In particular, succinylation of branched PEI resulted in up to 10-fold lower polymer toxicity in comparison to unmodified PEI. Formulations of siRNA with succinylated PEI were able to induce remarkable knockdown (80% relative to untreated cells) of target luciferase gene at the lowest tested siRNA concentration of 50 nM in Neuro2ALuc cells. The polyplex stability assay revealed that the efficiency of formulations which are stable in physiological saline is independent of the affinity of siRNA to the polymer chain. The improved properties of modified PEI as siRNA carrier are largely a consequence of the lower polymer toxicity. In order to achieve significant knockdown of target gene, the PEI-based polymer has to be applied at higher concentrations, required most probably for sufficient accumulation and proton sponge effects in endosomes. Unmodified PEI is highly toxic at such polymer concentrations. In contrast, the far less toxic modified analogues can be applied in concentrations required for the knockdown of target genes without side effects

Cognitively-Inspired Model for Incremental Learning Using a Few Examples

Incremental learning attempts to develop a classifier which learns continuously from a stream of data segregated into different classes. Deep learning approaches suffer from catastrophic forgetting when learning classes incrementally, while most incremental learning approaches require a large amount of training data per class. We examine the problem of incremental learning using only a few training examples, referred to as Few-Shot Incremental Learning (FSIL). To solve this problem, we propose a novel approach inspired by the concept learning model of the hippocampus and the neocortex that represents each image class as centroids and does not suffer from catastrophic forgetting. We evaluate our approach on three class-incremental learning benchmarks: Caltech-101, CUBS-200-2011 and CIFAR-100 for incremental and few-shot incremental learning and show that our approach achieves state-of-the-art results in terms of classification accuracy over all learned classes.Comment: Added link to the code in the pape

Renaissance or Revolution? Legacies of Pan-Arabism in the Egyptian Arab Spring

This project explores the degree that Pan-Arabism influenced in Egypt\u27s Arab Spring and how the Arab Spring represented the unfinished goals of decolonization in Egypt. The evidence suggests that the relationship between Pan-Arabism and the Arab Spring is complex. The promises of decolonization in the mid-twentieth century were economic and political independence with self-rule, explicitly separate from the influence of the colonizing powers, the British and French, Pan-Arabism promised social and political unity based on shared language and ethnicity and included broader goals such as the liberation of Palestine. During the decolonization campaign Gamal Abdel Nasser (1918-1970; PM 1954-56; Pres. 1956-1970) inexorably tied Pan-Arabism to Egyptian Nationalism. Many activists and leaders grew up under the influence of Nasser\u27s ideology and charismatic personality. The failure to deliver on the promises of Nasser\u27s ideology after 1952 resulted in the disenfranchisement of Egyptians and a renewed call for the promises of decolonization; free and fair elections, an end to emergency powers and military rule, decreased unemployment and inflation. The Arab Spring as a series of revolutions in Tunisia, Egypt, Syria, and Yemen represented the continuation of shared identity and Pan-Arab ideas decades after decolonization. It will be argued that even after 2011, questions of justice, leadership, and shared identity remain central to Egypt and beyond. In particular, evaluations of the Arab Spring and the negotiations between feminist organizations, religious organizations, and youth organizations in the development of a post-Arab Spring government are particularly relevant in light of the ongoing protests in Iran

A study of development of lean implementation process in customer services at Glamox: how it provides an opportunity for integration in a traditional lean manufacturing company with service-oriented settings and why it might allow value creation initiatives through waste elimination and concurrently filling inter and intra-firm service quality gaps

Confidential until 25-may-201