Towards rule-based visual programming of generic visual systems

This paper illustrates how the diagram programming language DiaPlan can be used to program visual systems. DiaPlan is a visual rule-based language that is founded on the computational model of graph transformation. The language supports object-oriented programming since its graphs are hierarchically structured. Typing allows the shape of these graphs to be specified recursively in order to increase program security. Thanks to its genericity, DiaPlan allows to implement systems that represent and manipulate data in arbitrary diagram notations. The environment for the language exploits the diagram editor generator DiaGen for providing genericity, and for implementing its user interface and type checker.Comment: 15 pages, 16 figures contribution to the First International Workshop on Rule-Based Programming (RULE'2000), September 19, 2000, Montreal, Canad

Theodore Antoniou: Celebration and Tribute, March 25, 2008

This is the concert program of the Theodore Antoniou: Celebration and Tribute performance on Tuesday, March 25, 2008 at 4:00 p.m., at the Concert Hall, 855 Commonwealthe Avenue. Works performed were KOMMOS B for orchestra by Theodore Antoniou, Cantilena (2nd mvt. of Concertino for Contrabass and Orchestra, piano reduction) by Theodore Antoniou, I Yria Zoi by Manolis Kalomiris, Fengaraki by Manos Hadzidakis, and Variations for Theodore by Julian Wachner, James Smith, Naftali Schindler, Apostolos Paraskevas, Reiko Yamada, Ivana Lisak, Pedro Malpica, Altin Volaj, and Alex Kalogeras. Digitization for Boston University Concert Programs was supported by the Boston University Center for the Humanities Library Endowed Fund

Intrinsic Motivation and Mental Replay enable Efficient Online Adaptation in Stochastic Recurrent Networks

Autonomous robots need to interact with unknown, unstructured and changing environments, constantly facing novel challenges. Therefore, continuous online adaptation for lifelong-learning and the need of sample-efficient mechanisms to adapt to changes in the environment, the constraints, the tasks, or the robot itself are crucial. In this work, we propose a novel framework for probabilistic online motion planning with online adaptation based on a bio-inspired stochastic recurrent neural network. By using learning signals which mimic the intrinsic motivation signalcognitive dissonance in addition with a mental replay strategy to intensify experiences, the stochastic recurrent network can learn from few physical interactions and adapts to novel environments in seconds. We evaluate our online planning and adaptation framework on an anthropomorphic KUKA LWR arm. The rapid online adaptation is shown by learning unknown workspace constraints sample-efficiently from few physical interactions while following given way points.Comment: accepted in Neural Network

Recombinant human follicle-stimulating hormone produces more oocytes with a lower total dose per cycle in assisted reproductive technologies compared with highly purified human menopausal gonadotrophin: a meta-analysis

<p>Abstract</p> <p>Background</p> <p>Human menopausal gonadotrophins and recombinant human follicle stimulating hormone are the two main gonadotrophin products utilized for controlled ovarian stimulation in assisted reproductive technologies. In this meta-analysis, the number of oocytes was designated as the most relevant endpoint directly resulting from ovarian stimulation, and therefore where the drug effect may be estimated with the best sensitivity.</p> <p>Methods</p> <p>All published randomized controlled trials on ovarian stimulation comparing the two gonadotrophin products were evaluated. Internal validity was determined using Chalmers' validated scale. If trials did not meet the established quality criteria, a sensitivity analysis assessed the stability of the results. The comparison of continuous variables was conducted following the weighted mean difference and the standardized mean difference (Cohen's effect size) with the random model. Given the known relationship of baseline conditions on treatment endpoints, results were adjusted for age, body mass index and type of infertility.</p> <p>Results</p> <p>Sixteen studies involving 4040 patients were included. Treatment with human menopausal gonadotrophins resulted in fewer oocytes (-1.54; 95% CI: -2.53 to -0.56; P < 0.0001) compared to recombinant human follicle-stimulating hormone. When adjusting for baseline conditions, the mean difference estimate was -2.10 (95% CI: -2.83 to -1.36; P < 0.001). A higher total dose of human menopausal gonadotrophin was necessary (mean difference, 235.46 IU [95% CI: 16.62 to 454.30; P = 0.03]; standardized mean difference, 0.33 [95% CI: 0.08 to 0.58; P = 0.01]). The pregnancy absolute risk difference (RD [hMG-r-hFSH]) for fresh transfers was 3% (P = 0.051), and the relative risk 1.10 (P = 0.06). When adjusted for baseline conditions, the relative risk was 1.04 (P = 0.49) and absolute difference was 0.01 (P = 0.34), respectively.</p> <p>Conclusions</p> <p>Because baseline conditions are predictive of outcome, meta-analytic results are more sensitive when these variables are considered. Using an endpoint closely associated with the stimulation period, sufficient sensitivity is achieved to compare gonadotrophin treatments. As the largest meta-analysis published to date on this subject, treatment with human menopausal gonadotrophins is characterized by fewer oocytes and a higher total dose. When considering only fresh transfers, pregnancy rates were similar.</p

Changes in adenosine receptors and neurotrophic factors in the SOD1G93A mouse model of amyotrophic lateral sclerosis: modulation by chronic caffeine

Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of corticospinal tract motor neurons. Previous studies showed that adenosine-mediated neuromodulation is disturbed in ALS and that vascular endothelial growth factor (VEGF) has a neuroprotective function in ALS mouse models. We evaluated how adenosine (A1R and A2AR) and VEGF (VEGFA, VEGFB, VEGFR-1 and VEGFR-2) system markers are altered in the cortex and spinal cord of pre-symptomatic and symptomatic SOD1G93A mice. We then assessed if/how chronic treatment of SOD1G93A mice with a widely consumed adenosine receptor antagonist, caffeine, modulates VEGF system and/or the levels of Brain-derived Neurotrophic Factor (BDNF), known to be under control of A2AR. We found out decreases in A1R and increases in A2AR levels even before disease onset. Concerning the VEGF system, we detected increases of VEGFB and VEGFR-2 levels in the spinal cord at pre-symptomatic stage, which reverses at the symptomatic stage, and decreases of VEGFA levels in the cortex, in very late disease states. Chronic treatment with caffeine rescued cortical A1R levels in SOD1G93A mice, bringing them to control levels, while rendering VEGF signaling nearly unaffected. In contrast, BDNF levels were significantly affected in SOD1G93A mice treated with caffeine, being decreased in the cortex and increased in spinal the cord. Altogether, these findings suggest an early dysfunction of the adenosinergic system in ALS and highlights the possibility that the negative influence of caffeine previously reported in ALS animal models results from interference with BDNF rather than with the VEGF signaling molecules.info:eu-repo/semantics/publishedVersio

A Systematic Approach to Constructing Incremental Topology Control Algorithms Using Graph Transformation

Communication networks form the backbone of our society. Topology control algorithms optimize the topology of such communication networks. Due to the importance of communication networks, a topology control algorithm should guarantee certain required consistency properties (e.g., connectivity of the topology), while achieving desired optimization properties (e.g., a bounded number of neighbors). Real-world topologies are dynamic (e.g., because nodes join, leave, or move within the network), which requires topology control algorithms to operate in an incremental way, i.e., based on the recently introduced modifications of a topology. Visual programming and specification languages are a proven means for specifying the structure as well as consistency and optimization properties of topologies. In this paper, we present a novel methodology, based on a visual graph transformation and graph constraint language, for developing incremental topology control algorithms that are guaranteed to fulfill a set of specified consistency and optimization constraints. More specifically, we model the possible modifications of a topology control algorithm and the environment using graph transformation rules, and we describe consistency and optimization properties using graph constraints. On this basis, we apply and extend a well-known constructive approach to derive refined graph transformation rules that preserve these graph constraints. We apply our methodology to re-engineer an established topology control algorithm, kTC, and evaluate it in a network simulation study to show the practical applicability of our approachComment: This document corresponds to the accepted manuscript of the referenced journal articl

The role of DNA polymerase fidelity on genetic variation and pathogenicity of Marek’s disease virus

Gallid herpesvirus 2, also known as Marek’s disease virus, is the causative agent of Marek’s disease in chickens that can cause up to 100 % mortality in unvaccinated hosts. Vaccination against MDV is one of the most successful vaccination campaigns in the history of veterinary medicine, reducing disease incidence by more than 99%. Despite this success, MDV is still prevalent in chicken flocks worldwide and has shown a remarkable increase in virulence over the past decades. A major reason for the persistence of MDV could be the fact that vaccination against MD is not inducing sterilizing immunity but is permissive for (reduced) viral replication and shedding. It is argued that the imperfection of vaccination drives viral evolution towards higher virulence by selecting for viral phenotypes that maintain lytic replication and thereby the ability to be shed and transmitted in the presence of vaccine-induced immune response. The phenotypes selected in this way could ultimately benefit from vaccination, as vaccinated chickens which survive the infection shed the most replication competent viruses for a prolonged time, and thus contribute to the spread and evolution of particularly virulent virus strains. As a result, the development of MDV vaccines is caught in a vicious circle – vaccination drives selection of rapidly replicating escape mutants, which requires development of new vaccines based on viral strains that can replicate in the vaccinated host. This scenario has indeed been observed with vaccines of the first and second generation. In the light of these possibilities, the increase in virulence observed during the last decades is undoubtedly alarming. In the context of selection for higher virulence, genetic variation of MDV in vaccinated hosts could provide a selective advantage similar to what is known for some RNA viruses, which have evolved error-prone genome replication and form highly diverse quasispecies. As large DNA virus, MDV is believed to be genetically relatively stable, employing a proofreading DNA polymerase for genome replication. There is, however, evidence for remarkable genetic variation among several large DNA viruses, including herpes viruses such as HCMV and HSV-1. The objectives of this study were 1) to develop a NGS sequencing strategy for this highly cell associated virus 2) to determine, if genetic variation in MDV is a function of the fidelity of its DNA polymerase and 3) to examine replicative fitness and pathogenicity of proofreading-deficient viruses in vivo. Following the development of a tiling array for highly specific capture of viral sequences from infected chicken cell extracts, we were able to sequence whole viral genomes from a variety of samples ranging from infected chicken embryonic cells to dust collected from chicken farms. Next, we constructed MDV mutants with point mutations, in the exonuclease and finger domain of Pol (UL30), that could enhance or reduce replication fidelity. The observed level of residual exonuclease activity correlated with the capacity of mutated viruses to replicate in cell culture. Viruses that encoded a DNA Pol which lacked the majority of its inherent exonuclease activity proved to be suicidal in cell culture, losing their replication fitness within a few passages after reconstitution from BAC DNA. Sequencing of clonal genomes obtained from virus propagated in chicken cells revealed that Pol mutants indeed exhibited higher mutation rates than wild type virus. Following in vitro characterization, three Pol mutants – a hypermutator (Y567F, mutation rate approximately 80-fold higher than WT), a weak mutator (Y547S, mutation rate approximately 3-fold higher than WT) and a putative hypomutator (L755F, mutation rate possibly slightly lower than WT) were examined in vivo. The survival of chickens indicates that a hypermutator phenotype (Y567F) is detrimental for viral pathogenicity while no significant difference between Y547S, L755F and WT was observed. Sequencing of MDV DNA enriched from different chicken tissues showed that this difference in virulence correlates with a higher mutation rate in the Y567F virus. Increasing the mutation rate through reducing MDV Pol fidelity seems to be deleterious for the replicative capacity and fitness of MDV in vitro as well as in vivo through generation of an excessive number of mutations. Nevertheless, the potential of escaping this “error catastrophe” by partial repair of exonuclease function and establishment of a highly diverse viral population with WT like fitness was observed in cell culture for one of the hypermutator mutants (Y567F). The formation of functional and hyperdiverse populations by Pol mutant herpesviruses should be further investigated with special respect to potential quasispecies population dynamics

Nutrients, Nutraceuticals and Bioactive Properties of Multi-Whole Grain Mix for Drink and Porridge

Whole grains are reported to be rich in nutrients, nutraceuticals and have number of health beneficial effects. A convenient multi-whole grain mix for the preparation of a drink or porridge was formulated by using cereals, millets, pulses and nuts. Particle size was mostly of 180-250 microns (52%). Amylograph characteristics like GT, PV, HPV, CPV were 82°C, 285BU, 310BU, and 605BU, respectively were ideal for drink. The mix was found to be rich in carbohydrate, protein, fibre and calorie. The 100g of the mix had nutraceuticals like carotenoids (290µg), γ-tocopherol (4.6mg), α-tocopherol (1.5mg), and polyphenols-soluble, bound and total (94,132 and 226mg GA Eq.). Bioactive properties like vitamin E activity, free radical scavenging activity, total antioxidant activity and starch digestibility were 2.6i.u., 153mg catechin.Eq./100g, 17mg Tocopherol equivalent and 61.8%. Mix was sensorily acceptable in the form of drink and porridge and can be used as an ideal nutritious food for all age group