A Population-Based Ultra-Widefield Digital Image Grading Study for Age-Related Macular Degeneration-Like Lesions at the Peripheral Retina.

Our understanding of the relevance of peripheral retinal abnormalities to disease in general and in age-related macular degeneration (AMD) in particular is limited by the lack of detailed peripheral imaging studies. The purpose of this study was to develop image grading protocols suited to ultra-widefield imaging (UWFI) in an aged population

Towards new hard materials by structuring soft matter

No abstract

Probing multivalent interactions in a synthetic host-guest complex by dynamic force spectroscopy

Multivalency is present in many biological and synthetic systems. Successful application of multivalency depends on a correct understanding of the thermodynamics and kinetics of this phenomenon. In this Article, we address the stability and strength of multivalent bonds with force spectroscopy techniques employing a synthetic adamantane/β-cyclodextrin model system. Comparing the experimental findings to theoretical predictions for the rupture force and the kinetic off-rate, we find that when the valency of the complex is increased from mono- to di- to trivalent, there is a transition from quasi-equilibrium, with a constant rupture force of 99 pN, to a kinetically dependent state, with loading-rate-dependent rupture forces from 140 to 184 pN (divalent) and 175 to 210 pN (trivalent). Additional binding geometries, parallel monovalent ruptures, single-bound divalent ruptures, and single- and double-bound trivalent ruptures are identified. The experimental kinetic off-rates of the multivalent complexes show that the stability of the complexes is significantly enhanced with the number of bonds, in agreement with the predictions of a noncooperative multivalent model

CONSIDERATIONS REGARDING SYSTEMIC INTERACTION OF LAW WITH OTHER SOCIAL NORMATIVE SUBSYSTEMS

This article tackles the issue of systemic interaction between various normative systems. As such, it addresses and analyses the system of law from the perspective the general systems theory. More than that, the paper analyses the links and interactions between various normative systems, called sub-systems in the paper, and the division of law, namely public law and private law

Design and operation of a Tesla-type valve for pulsating heat pipes

AbstractA new Tesla-type valve is successfully designed for promoting circulation in a pulsating heat pipe (PHP) and improving the thermal resistance. Its functionality and diodicity is tested by laminar single-phase modelling and by steady two-phase flow experiments. The valve is symmetrically integrated in a single-turn PHP, which reduces variabilities to give a more thorough understanding of the behaviour in PHPs. Two transparent bottom-heated PHPs, one with and one without valves, are manufactured and the flow behaviour and thermal performance is studied. The valves produced a diodicity which lead to a difference in velocity of 25% for the different flow directions. Furthermore, a decrease of 14% in thermal resistance was observed due to the addition of the valves

A method for identifying alternative or cryptic donor splice sites within gene and mRNA sequences. Comparisons among sequences from vertebrates, echinoderms and other groups

<p>Abstract</p> <p>Background</p> <p>As the amount of genome sequencing data grows, so does the problem of computational gene identification, and in particular, the splicing signals that flank exon borders. Traditional methods for identifying splicing signals have been created and optimized using sequences from model organisms, mostly vertebrate and yeast species. However, as genome sequencing extends across the animal kingdom and includes various invertebrate species, the need for mechanisms to recognize splice signals in these organisms increases as well. With that aim in mind, we generated a model for identifying donor and acceptor splice sites that was optimized using sequences from the purple sea urchin, <it>Strongylocentrotus purpuratus</it>. This model was then used to assess the possibility of alternative or cryptic splicing within the highly variable immune response gene family known as <it>185/333</it>.</p> <p>Results</p> <p>A donor splice site model was generated from <it>S. purpuratus </it>sequences that incorporates non-adjacent dependences among positions within the 9 nt splice signal and uses position weight matrices to determine the probability that the site is used for splicing. The <it>Purpuratus </it>model was shown to predict splice signals better than a similar model created from vertebrate sequences. Although the <it>Purpuratus </it>model was able to correctly predict the true splice sites within the <it>185/333 </it>genes, no evidence for alternative or trans-gene splicing was observed.</p> <p>Conclusion</p> <p>The data presented herein describe the first published analyses of echinoderm splice sites and suggest that the previous methods of identifying splice signals that are based largely on vertebrate sequences may be insufficient. Furthermore, alternative or trans-gene splicing does not appear to be acting as a diversification mechanism in the <it>185/333 </it>gene family.</p

Identification of increased blue light reflectivity in macular telangiectasia type 2 using scanning laser ophthalmoscopy versus red-free fundus photography

PURPOSE: To compare two modalities used for detection of the characteristic parafoveal hyperreflective area seen in macular telangiectasia Type 2. METHODS: Scanning laser ophthalmoscope blue light reflectance was compared with red-free fundus photography imaging. Images were obtained as part of the international Natural History Study of Macular Telangiectasia (MacTel Study). RESULTS: The hyperreflective area can more frequently be seen with scanning laser ophthalmoscope blue light reflectance than with red-free imaging. CONCLUSION: Detection of the hyperreflective area might help to identify macular telangiectasia in earlier disease stages. Scanning laser ophthalmoscope blue light reflectance should be preferred as a diagnostic tool when the suspicion of macular telangiectasia arises. However, red-free imaging offers a viable option to scanning laser ophthalmoscope blue light reflectance when good quality is achieved

Karst of Western Cuba: Observations, Geomorphology, and Diagenesis

In Cuba, we observed many karst features in a variety of hydrogeologic settings. These hy-drogeologic settings occur in close proximity only because of the complex tectonic history of the is-land. We observed caves within rocks ranging from Pleistocene to Jurassic, and representing a range of diagenetic ages from eogenetic to teloge-netic. Our observations are from the western one-third of the island of Cuba; however, we believe they are representative of hydrogeologic settings found throughout the island

Chromosome-End Knockoff Strategy to Reshape Alkaloid Profiles of a Fungal Endophyte

Molecular genetic techniques to precisely eliminate genes in asexual filamentous fungi require the introduction of a marker gene into the target genome. We developed a novel strategy to eliminate genes or gene clusters located in subterminal regions of chromosomes, and then eliminate the marker gene and vector backbone used in the transformation procedure. Because many toxin gene clusters are subterminal, this method is particularly suited to generating nontoxic fungal strains. We tested this technique on Epichloë coenophiala, a seed-transmissible symbiotic fungus (endophyte) of the important forage grass, tall fescue (Lolium arundinaceum). The endophyte is necessary for maximal productivity and sustainability of this grass but can produce ergot alkaloids such as ergovaline, which are toxic to livestock. The genome sequence of E. coenophiala strain e19 revealed two paralogous ergot alkaloid biosynthesis gene clusters, designated EAS1 and EAS2. EAS1 was apparently subterminal, and the lpsB copy in EAS2 had a frame-shift mutation. We designed a vector with a fungal-active hygromycin phosphotransferase gene (hph), an lpsA1 gene fragment for homologous recombination at the telomere-distal end of EAS1, and a telomere repeat array positioned to drive spontaneous loss of hph and other vector sequences, and to stabilize the new chromosome end. We transformed E. coenophiala with this vector, then selected “knockoff” endophyte strains, confirmed by genome sequencing to lack 162 kb of a chromosome end including most of EAS1, and also to lack vector sequences. These ∆EAS1 knockoff strains produced no detectable ergovaline, whereas complementation with functional lpsB restored ergovaline production