The Rényi Redundancy of Generalized Huffman Codes

Huffman's algorithm gives optimal codes, as measured by average codeword length, and the redundancy can be measured as the difference between the average codeword length and Shannon's entropy. If the objective function is replaced by an exponentially weighted average, then a simple modification of Huffman's algorithm gives optimal codes. The redundancy can now be measured as the difference between this new average and A. Renyi's (1961) generalization of Shannon's entropy. By decreasing some of the codeword lengths in a Shannon code, the upper bound on the redundancy given in the standard proof of the noiseless source coding theorem is improved. The lower bound is improved by randomizing between codeword lengths, allowing linear programming techniques to be used on an integer programming problem. These bounds are shown to be asymptotically equal. The results are generalized to the Renyi case and are related to R.G. Gallager's (1978) bound on the redundancy of Huffman codes

Alien Registration- Helin, C Anselm (Waldoboro, Lincoln County)

https://digitalmaine.com/alien_docs/12905/thumbnail.jp

Gravitational GUT Breaking and the GUT-Planck Hierarchy

It is shown that non-renormalizable gravitational interactions in the Higgs sector of supersymmetric grand unified theories (GUT's) can produce the breaking of the unifying gauge group $G$ at the GUT scale $M_{\rm GUT} \sim 10^{16}$~GeV. Such a breaking offers an attractive alternative to the traditional method where the superheavy GUT scale mass parameters are added ad hoc into the theory. The mechanism also offers a natural explanation for the closeness of the GUT breaking scale to the Planck scale. A study of the minimal SU(5) model endowed with this mechanism is presented and shown to be phenomenologically viable. A second model is examined where the Higgs doublets are kept naturally light as Goldstone modes. This latter model also achieves breaking of $G$ at $M_{\rm GUT}$ but cannot easily satisfy the current experimental proton decay bound.Comment: 11 pages, REVTeX, 1 figure included as an uuencoded Z-compressed PostScript file. Our Web page at http://physics.tamu.edu/~urano/research/gutplanck.html contains ready to print PostScript version (with figures) as well as color version of plot

Staining and peeling of the internal limiting membrane using a fluorescent dye (Rhodamine 6 G)

Aim: To assess whether low concentrations of a fluorescent dye such as Rhodamine 6G would help the unaided human eye visualise the vitreous and the internal limiting membrane (ILM) under standard halogen illumination.Material/methods: The UV/Vis absorption (E) and fluorescence (I) spectra of Rhodamine 6G in water were measured and compared with Indocyanine Green (ICG). Surgery was performed in two rhesus monkeys and consisted of standard pars plana vitrectomy with halogen light source used for illumination. Rhodamine 6G was diluted in balanced salt solution (BSS). A few drops of the dye in a concentration of 0.1% (307 mOsm) were applied over the posterior pole in the air-filled globe and washed out by irrigation after 1 min. Immediately after surgery, the globes were enucleated, fixated and prepared for histological evaluation.Results: In contrast to ICG, both the maximum of the absorption and emission of Rhodamin 6G are very much within the spectral sensitivity of the human eye. The Rhodamine 6G--BSS itself appears red in colour. Using a dye concentration of 0.1%, there was no visible red-staining of the ILM as such. As the dye was irrigated out with BSS, a marked green fluorescence of the fluid within the vitreous cavity was noted. With halogen illumination through a standard 20-gauge light pipe, the dye provided a sufficient green fluorescence to identify and safely remove the ILM and to clearly differentiate areas of peeled from non-peeled ILM. During light microscopy, eyes revealed a peeled ILM demarcation with no signs of acute retinal toxicity.Conclusion: The findings indicate that a fluorescent dye can be used for ILM peeling. Assuming that the fluorophore provides a high enough fluorescence quantum yield after adsorption to the ILM, much lower dye concentrations could be used compared with absorbent dyes, thereby minimising toxic effects

Internal Controls, and the Incidence of Fraud in Microfinance Inststutions in the Southwest Region of Cameroon

This paper aims at investigating how internal controls affect the incidence and the levels of fraud in selected microfinance institutions in Cameroon. The primary method of data collection was implemented where questionnaires were issued to employees of selected microfinance institutions. The Ordinary Least Square technique of data estimation was implemented from which a regression analysis was run. Correlation analysis and descriptive statistical analysis were also among the analytical tools used for the paper. The finding shows a statistically significant negative relationship between sound internal control and fraud management policies and the incidence of fraud in the microfinance institutions

Heterozygous mis-sense mutations in Prkcb as a critical determinant of anti-polysaccharide antibody formation

To identify rate-limiting steps in T cell-independent type 2 (TI-2) antibody production against polysaccharide antigens, we performed a genome-wide screen by immunizing several hundred pedigrees of C57BL/6 mice segregating ENU-induced mis-sense mutations. Two independent mutations, Tilcara and Untied, were isolated that semi-dominantly diminished antibody against polysaccharide but not protein antigens. Both mutations resulted from single amino acid substitutions within the kinase domain of Protein Kinase C Beta (PKCβ). In Tilcara, a Ser552>Pro mutation occurred in helix G, in close proximity to a docking site for the inhibitory N-terminal pseudosubstrate domain of the enzyme, resulting in almost complete loss of active, autophosphorylated PKCβI whereas the amount of alternatively spliced PKCβII protein was not markedly reduced. Circulating B cell subsets were normal and acute responses to BCR-stimulation such as CD25 induction and initiation of DNA synthesis were only measurably diminished in Tilcara homozygotes, whereas the fraction of cells that had divided multiple times was decreased to an intermediate degree in heterozygotes. These results, coupled with evidence of numerous mis-sense PRKCB mutations in the human genome, identify Prkcb as a genetically sensitive step likely to contribute substantially to population variability in anti-polysaccharide antibody levels

Intravitreal bevacizumab for the treatment of macular oedema secondary to branch retinal vein occlusion

Purpose: To evaluate the effect of intravitreal bevacizumab (Avastin) injections on visual acuity (VA) and foveal retinal thickness in patients with macular oedema secondary to branch retinal vein occlusion.Methods: A prospective, non-comparative, consecutive, interventional case series of 34 patients. Patients received repeated intravitreal injections of 1.25 mg bevacizumab. Main outcome measures were VA (Snellen charts and ETDRS) and retinal thickness (optical coherence tomography measurements) in a follow-up period of 6 months.Results: Patients presented at a mean age of 69 years (range 44--86). Mean duration of symptoms was 40 weeks (range 1--300). Mean (SD) VA at baseline was 0.79 (0.39) logMAR, improving to 0.51 (0.34) logMAR at 6 months (p = 0.009). Mean number of letters on the ETDRS chart at baseline was 45.3 (19.0), improving to 60.6 (19.9) at 6 months (p = 0.003). Mean (SD) retinal thickness at baseline was 474 (120) \textgreekmm, declining to 316 (41) \textgreekmm at 6 months.Conclusion: Intravitreal injection of 1.25 mg bevacizumb appears to be an effective treatment option for branch retinal vein occlusion

Auxetic behavior of fiber networks: Paper and nonwoven fabrics

Auxetic materials/structures have been subjects of scientific curiosity due to their counterintuitive response to deformation; specifically, they exhibit a negative Poisson’s ratio. While some natural materials are auxetic, scientists and engineers have sought to produce this property in synthetic materials/structures with a goal of improving properties such as damping and producing composites with mechanically interlocking interfaces. The objective of this research was to more fully understand the out-of-plane auxetic response of engineered fiber structures, specifically paper [1] and nonwoven fabrics [2, 3]. Several paper samples and handsheets were tested to quantify their auxetic response and understand how processing and structure affected their auxeticity. The results showed that paper structures possessed a wide distribution of Poisson’s ratio values, both positive and negative. The difference in the values of Poisson’s ratio suggested a strong correlation with the fiber-network structure and the processing conditions employed during papermaking. The nonwoven fabrics studied were needle-punched nonwoven fabrics. These fabrics contained pillars of entangled fibers that were oriented roughly parallel to the thickness direction, and they were not auxetic in their as-produced state. To produce an auxetic response, a post-processing heat compression step was explored to orient more of the fibers in the plane and produce additional fiber junction points. Large, negative values for Poisson’s ratio were observed for the fabrics after heat compression. Of the available processing parameters, temperature was found to affect the auxetic response most strongly, by increasing the compression set of the fabric and, as a result, the auxetic response. Overall, these results showed some commonality between the two systems studied in that fiber network structure and fiber junctions worked together to produce an out-of-plane auxetic response. Additionally, these structural attributes may provide general design guidelines for producing these auxetic fiber structures from other materials, leading to their use in composites. References 1. Verma, P., M.L. Shofner, and A.C. Griffin, Deconstructing the auxetic behavior of paper. Physica Status Solidi (b) – Basic Solid State Physics, 2014. 251(2): 289-296. 2. Verma, P., M.L. Shofner, A. Lin, K.B. Wagner, and A.C. Griffin, Inducing out-of-plane auxetic behavior in needle-punched nonwovens. Physica Status Solidi (b) – Basic Solid State Physics, 2015. 252(7): 1455-1464. 3. Verma, P., M.L. Shofner, A. Lin, K.B. Wagner, and A.C. Griffin, Induction of auxetic response in needle-punched nonwovens: Effects of temperature, pressure and time. Physica Status Solidi (b) – Basic Solid State Physics, 2016. 253(7): 1270-1278

Sorafenib prevents human retinal pigment epithelium cells from light-induced overexpression of VEGF, PDGF and PlGF

Background Cumulative light exposure is significantly associated with progression of age-related macular degeneration (AMD). Inhibition of vascular endothelial growth factor is the main target of current antiangiogenic treatment strategies in AMD. However, other growth factors, such as platelet-derived growth factor (PDGF) and placenta growth factor (PlGF), have a substantial impact on development of AMD. Previous reports indicate that sorafenib, an oral multikinase inhibitor, might have beneficial effects on exudative AMD. This study investigates the effects of sorafenib on light-induced overexpression of growth factors in human retinal pigment epithelial (RPE) cells. Methods Primary human RPE cells were exposed to white light and incubated with sorafenib. Viability, expression, and secretion of VEGF-A, PDGF-BB, and PlGF and their mRNA were determined by reverse transcription-polymerase chain reactions, immunohistochemistry and enzyme-linked immunosorbent assays. Results Light exposure decreased cell viability and increased expression and secretion of VEGF-A, PDGF-BB and PlGF. These light-induced effects were significantly reduced when cells were treated with sorafenib at a dose of 1 mu g/ml. Conclusion The results show that sorafenib has promising properties as a potential antiangiogenic treatment for AMD