38 research outputs found

    Effective superpotentials for B-branes in Landau-Ginzburg models

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    We compute the partition function for the topological Landau-Ginzburg B-model on the disk. This is done by treating the worldsheet superpotential perturbatively. We argue that this partition function as a function of bulk and boundary perturbations may be identified with the effective D-brane superpotential in the target spacetime. We point out the relationship of this approach to matrix factorizations. Using these methods, we prove a conjecture for the effective superpotential of Herbst, Lazaroiu and Lerche for the A-type minimal models. We also consider the Landau-Ginzburg theory of the cubic torus where we show that the effective superpotential, given by the partition function, is consistent with the one obtained by summing up disk instantons in the mirror A-model. This is done by explicitly constructing the open-string mirror map.Comment: 57p, 7 figs, harvma

    Matrix Factorizations, Minimal Models and Massey Products

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    We present a method to compute the full non-linear deformations of matrix factorizations for ADE minimal models. This method is based on the calculation of higher products in the cohomology, called Massey products. The algorithm yields a polynomial ring whose vanishing relations encode the obstructions of the deformations of the D-branes characterized by these matrix factorizations. This coincides with the critical locus of the effective superpotential which can be computed by integrating these relations. Our results for the effective superpotential are in agreement with those obtained from solving the A-infinity relations. We point out a relation to the superpotentials of Kazama-Suzuki models. We will illustrate our findings by various examples, putting emphasis on the E_6 minimal model.Comment: 32 pages, v2: typos corrected, v3: additional comments concerning the bulk-boundary crossing constraint, some small clarifications, typo

    Integrating Telemedicine Solutions with Electronic Health Records; Evaluation of Alternatives based on the Proposed Reference Architecture for Norway. Report 02-2016

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    This report studies the way forward for how a telemedicine solution can be integrated for exchange of data with an existing Electronic Health Record (EHR) system. The solution used an example for this report is based on a telemedicine solution for COPD patients (Chronic Obstructive Pulmonary Disease) developed in the project “Collaborative Point-of-Care Services Agder: Follow-up of COPD patients as part of the United4Health EU Project», with financial support from the Research Council of Norway. In addition, the EHR solution from DIPS ASA is used as an example of an existing system for integration. Important parameters for choosing way forward on how to are: urgency with regards to timeline level of structuring of the data. compliance with the reference architecture1proposed by the Norwegian Directorate of eHealth (NDE) Three alternative ways forward are discussed in this report, based on four different scenarios with their respectively defined use-cases. Possibilities of integration exists already today which may support one of the use cases in the simplest way, but may not be a futureproof solution regarding functionality and recommended standards. Such a solution is supported by DIPS Classic as well as DIPS Arena by using HL7 V3 interface in DIPS. The journal data may be stored in an unstructured way as a PDF document in a patients EHR. To send structured data from a Telemedicine System to an EHR will be the preferred way for the future, and will support several use cases in a more efficient way. This will require more work in total and is dependent on other parties (external storage, DIPS etc) for building infrastructure and new interfaces. Such solutions will still be of high interest in the future. This report describes two different scenarios for how such solutions can be implemented in the future using either external storage and XDS.b or using FHIR/OpenEHR. Which of these alternatives that will be the leading standard or best practice is hard to predict, since it will highly depend on how the user requirements from the health care market will request such solutions, and how the standardization requirements from National authorities evolves in the next years. In addition, it depends on how the developers/vendors of both telemedicine solutions and EHR-systems will responds to these requirements

    Integrating Telemedicine Solutions with Electronic Health Records; Evaluation of Alternatives based on the Proposed Reference Architecture for Norway

    Get PDF
    This report studies the way forward for how a telemedicine solution can be integrated for exchange of data with an existing Electronic Health Record (EHR) system. The solution used an example for this report is based on a telemedicine solution for COPD patients (Chronic Obstructive Pulmonary Disease) developed in the project “Collaborative Point-of-Care Services Agder: Follow-up of COPD patients as part of the United4Health EU Project», with financial support from the Research Council of Norway. In addition, the EHR solution from DIPS ASA is used as an example of an existing system for integration. Important parameters for choosing way forward on how to are: • urgency with regards to timeline • level of structuring of the data. • compliance with the reference architecture proposed by the Norwegian Directorate of eHealth (NDE) Three alternative ways forward are discussed in this report, based on four different scenarios with their respectively defined use-cases. Possibilities of integration exists already today which may support one of the use cases in the simplest way, but may not be a futureproof solution regarding functionality and recommended standards. Such a solution is supported by DIPS Classic as well as DIPS Arena by using HL7 V3 interface in DIPS. The journal data may be stored in an unstructured way as a PDF document in a patients EHR. To send structured data from a Telemedicine System to an EHR will be the preferred way for the future, and will support several use cases in a more efficient way. This will require more work in total and is dependent on other parties (external storage, DIPS etc) for building infrastructure and new interfaces. Such solutions will still be of high interest in the future. This report describes two different scenarios for how such solutions can be implemented in the future using either external storage and XDS.b or using FHIR/OpenEHR. Which of these alternatives that will be the leading standard or best practice is hard to predict, since it will highly depend on how the user requirements from the health care market will request such solutions, and how the standardization requirements from National authorities evolves in the next years. In addition, it depends on how the developers/vendors of both telemedicine solutions and EHR-systems will responds to these requirements

    Algorithmic deformation of matrix factorisations

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    Branes and defects in topological Landau-Ginzburg models are described by matrix factorisations. We revisit the problem of deforming them and discuss various deformation methods as well as their relations. We have implemented these algorithms and apply them to several examples. Apart from explicit results in concrete cases, this leads to a novel way to generate new matrix factorisations via nilpotent substitutions, and to criteria whether boundary obstructions can be lifted by bulk deformations.Comment: 30 page

    Genotype-Phenotype Correlation in NF1: Evidence for a More Severe Phenotype Associated with Missense Mutations Affecting NF1 Codons 844–848

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    Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000–3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons—Leu844, Cys845, Ala846, Leu847, and Gly848—located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844–848 exists and will be valuable in the management and genetic counseling of a significant number of individuals

    High incidence of Noonan syndrome features including short stature and pulmonic stenosis in patients carrying NF1 missense mutations affecting p.Arg1809: genotype-phenotype correlation

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    Neurofibromatosis type 1 (NF1) is one of the most frequent genetic disorders, affecting 1:3,000 worldwide. Identification of genotype-phenotype correlations is challenging because of the wide range clinical variability, the progressive nature of the disorder, and extreme diversity of the mutational spectrum. We report 136 individuals with a distinct phenotype carrying one of five different NF1 missense mutations affecting p.Arg1809. Patients presented with multiple cafe-au-lait macules (CALM) with or without freckling and Lisch nodules, but no externally visible plexiform neurofibromas or clear cutaneous neurofibromas were found. About 25% of the individuals had Noonan-like features. Pulmonic stenosis and short stature were significantly more prevalent compared with classic cohorts (P<0.0001). Developmental delays and/or learning disabilities were reported in over 50% of patients. Melanocytes cultured from a CALM in a segmental NF1-patient showed two different somatic NF1 mutations, p.Arg1809Cys and a multi-exon deletion, providing genetic evidence that p.Arg1809Cys is a loss-of-function mutation in the melanocytes and causes a pigmentary phenotype. Constitutional missense mutations at p.Arg1809 affect 1.23% of unrelated NF1 probands in the UAB cohort, therefore this specific NF1 genotype-phenotype correlation will affect counseling and management of a significant number of patients

    Expanding the clinical phenotype of individuals with a 3-bp in-frame deletion of the NF1 gene (c.2970_2972del): an update of genotype–phenotype correlation

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    Purpose: Neurofibromatosis type 1 (NF1) is characterized by a highly variable clinical presentation, but almost all NF1-affected adults present with cutaneous and/or subcutaneous neurofibromas. Exceptions are individuals heterozygous for the NF1 in-frame deletion, c.2970_2972del (p.Met992del), associated with a mild phenotype without any externally visible tumors. Methods: A total of 135 individuals from 103 unrelated families, all carrying the constitutional NF1 p.Met992del pathogenic variant and clinically assessed using the same standardized phenotypic checklist form, were included in this study. Results: None of the individuals had externally visible plexiform or histopathologically confirmed cutaneous or subcutaneous neurofibromas. We did not identify any complications, such as symptomatic optic pathway gliomas (OPGs) or symptomatic spinal neurofibromas; however, 4.8% of individuals had nonoptic brain tumors, mostly low-grade and asymptomatic, and 38.8% had cognitive impairment/learning disabilities. In an individual with the NF1 constitutional c.2970_2972del and three astrocytomas, we provided proof that all were NF1-associated tumors given loss of heterozygosity at three intragenic NF1 microsatellite markers and c.2970_297
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