Efficiency improvements in a dichroic dye-doped liquid crystal Fresnel lens

A dichroic dye-doped liquid crystal Fresnel lens was fabricated and investigated to observe the combination of phase and amplitude modulation based focusing. An anthraquinone dichroic dye was doped into a liquid crystal host, which when in the Fresnel lens configuration generates a Fresnel zone plate with alternating “transparent” and “opaque” zones. The zones were induced by using photo-alignment of a light-sensitive alignment layer to generate the alternating pattern. The voltage dependency of efficiency for the dye doped and pure liquid crystal Fresnel devices were investigated. Incorporation of dyes into the device yielded a significant 4 % improvement in relative efficiency in the lens, giving a maximum of 37 % achieved in the device, much closer to the theoretical 41 % limit when compared with the non dye doped device. The input polarization dependence of efficiency was also investigated, showing very small fluctuations (±1.5 %), allowing further insight into the effect of fabrication method on these liquid crystal Fresnel devices

Post-transcriptional control of tumor cell autonomous metastatic potential by the CCR4-NOT deadenylase CNOT7

Accumulating evidence supports the role of an aberrant transcriptome as a driver of metastatic potential. Deadenylation is a general regulatory node for post-transcriptional control by microRNAs and other determinants of RNA stability. Previously, we demonstrated that the CCR4-NOT scaffold component Cnot2 is an inherited metastasis susceptibility gene. In this study, using orthotopic metastasis assays and genetically engineered mouse models, we show that one of the enzymatic subunits of the CCR4-NOT complex, Cnot7, is also a metastasis modifying gene. We demonstrate that higher expression of Cnot7 drives tumor cell autonomous metastatic potential, which requires its deadenylase activity. Furthermore, metastasis promotion by CNOT7 is dependent on interaction with CNOT1 and TOB1. CNOT7 ribonucleoprotein-immunoprecipitation (RIP) and integrated transcriptome wide analyses reveal that CNOT7-regulated transcripts are enriched for a tripartite 3’UTR motif bound by RNA-binding proteins known to complex with CNOT7, TOB1, and CNOT1. Collectively, our data support a model of CNOT7, TOB1, CNOT1, and RNA-binding proteins collectively exerting post-transcriptional control on a metastasis suppressive transcriptional program to drive tumor cell metastasis

Data for Embossing Reactive Mesogens: A Facile Approach to Polarisation-Independent Liquid Crystal Devices

Reactive mesogens (RMs) have found their way into different branches of science and application. They can be processed as standard liquid crystals and can then be polymerised to stabilise their shape and anisotropic properties. Their birefringence is used in optical compensation films while the complex director field is exploited for actuators. However, creating complex shapes while maintaining good alignment is a challenge in these applications. In the present work, the embossing of reactive mesogens is introduced. Embossing is a fast and large-scale method, which allows to form a large variety of structured reactive mesogen devices. To create a polarisation-independent lens, two birefringent Fresnel zone plates (FZPs) are embossed. A lens is formed by assembling the FZPs in a twisted nematic cell and filling the cell with a nematic crystal index matched to the RM. The device can be switched from a non-focusing to a focusing state by applying a small voltage. After characterising the efficiency and beam properties, the method is used to fabricate a switchable multi-level Fresnel zone plate with optical efficiencies beyond 50%. Finally, manufactured polarisation-independent gratings and microlens arrays are presented using the method to illustrate the wide range of applicability

An experimental study of optical anisotropy of blue-phase liquid crystals as a function of alignment layers

The growing requirements for ultrafast communication speeds are constantly pushing the need to explore new devices and materials to reduce bottlenecks in optical communication networks. One such device is a phase only spatial light modulator implemented using liquid crystal on silicon. Achieving this requires polarization independent and fast-switching optical materials. Blue-phase liquid crystal is one such candidate. Popular opinion is that blue-phase liquid crystal is polarization-independent. In this study using microscopic and polarimetric methods, we demonstrate that in the off-state of blue-phase, the alignment layers affect the optical polarization behavior

Computing solution-compensation spaces using an enhanced Fourier-Motzkin algorithm

In complex system design, design variables can be divided into two groups, early‐ and late‐decision variables. Early‐decision variables are equipped with tolerance regions which are specified during the early stages of the development process. Tolerance is necessary to account for changes of design variable values due to later and therefore unknown, design restrictions. In this sense, early‐decision variables are subject to lack‐of‐knowledge uncertainty. Tolerance regions for early‐decision variables can be significantly increased by the use of late‐decision variables. The latter are not equipped with tolerance regions and, by contrast, have to be arbitrarily well adjustable within their design intervals. The values of late‐decision variables are chosen in a later development phase when further design restrictions are known. Late‐decision variables then may compensate for the choice of early‐decision variables. Solution‐compensation spaces are regions of early‐ and late‐decision variables where for all values of early‐decision variables values for late‐decision variables from their associated intervals exist such that all design requirements are satisfied. A new approach to compute solution‐compensation spaces for linear systems is introduced. It is based on an enhanced Fourier‐Motzkin‐Elimination algorithm which uses H‐redundancy removal. The new algorithm is applied to a design problem from vehicle dynamics and we show that it outperforms the so‐called basic projection algorithm presented in [ Vogt M. E., Duddeck F., Wahle M., Zimmermann M. "Optimizing tolerance to uncertainty in systems design with early-and late-decision  variables." IMA Journal of Management Mathematics]

Resequencing of VAX1 in patients with nonsyndromic cleft lip with or without cleft palate

BACKGROUND: Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common of all congenital anomalies, and has a multifactorial etiology involving both environmental and genetic factors. Recent genome-wide association studies (GWAS) identified strong association between a locus on chromosome 10q25.3 and NSCL/P in European samples. One gene at 10q25.3, the ventral anterior homeobox 1 (VAX1) gene, is considered a strong candidate gene for craniofacial malformations. The purpose of the present study was to provide further evidence that VAX1 is the causal gene at the 10q25.3 locus through identification of an excess of rare mutations in patients with NSCL/P. METHODS: The 5'UTR, complete coding regions, and adjacent splice sites of the two known VAX1 isoforms were sequenced in 384 patients with NSCL/P and 384 controls of Central European descent. Observed variants were investigated with respect to familial cosegregation or de novo occurrence, and in silico analyses were performed to identify putative effects on the transcript or protein level. RESULTS: Eighteen single-base variants were found, 15 of them rare and previously unreported. In the long VAX1 isoform, predicted functionally relevant variants were observed more often in NSCL/P cases, although this difference was not significant (p = 0.17). Analysis of family members demonstrated incomplete cosegregation in most pedigrees. CONCLUSION: Our data do not support the hypothesis that highly penetrant rare variants in VAX1 are a cause of NSCL/P. To determine whether VAX1 is the causative gene at 10q25.3 further research, in particular into the biologic function of its long isoform, is warranted. Birth Defects Research (Part A), 2012. (c) 2012 Wiley Periodicals, Inc

PAX8 and MECOM are interaction partners driving Ovarian Carcinogenesis

The transcription factor PAX8 is critical for the development of the thyroid and urogenital system. Comprehensive genomic screens furthermore indicate an additional oncogenic role for PAX8 in renal and ovarian carcinogenesis. While a plethora of PAX8-regulated genes in different contexts have been proposed, we still lack a mechanistic understanding of how PAX8 engages molecular complexes to drive disease-relevant oncogenic transcriptional programs. Here we show that protein isoforms originating from the MECOM locus form a complex with PAX8. This includes PRDM3 (also called MDS1-EVI1) for which we map its interaction with PAX8 in vitro and in vivo. We show that PAX8 binds a large number of genomic sites and forms transcriptional hubs. At a subset of these, PAX8 together with PRDM3 regulate a specific gene expression module involved in adhesion and extracellular matrix. This gene module correlates with PAX8 and MECOM expression in large scale profiling of cell lines, PTXs and clinical cases and stratifies gynecological cancer cases with worse prognosis. PRDM3 is amplified in Ovarian Cancers and we show that the MECOM locus and PAX8 sustain in-vivo ovarian cancer growth, further supporting that the identified function of the MECOM locus underlies PAX8-driven oncogenic functions in ovarian cancer