257 research outputs found

    Pseudo-K\"ahler Lie algebras with abelian complex structures

    Full text link
    We study Lie algebras endowed with an abelian complex structure which admit a symplectic form compatible with the complex structure. We prove that each of those Lie algebras is completely determined by a pair (U,H) where U is a complex commutative associative algebra and H is a sesquilinear hermitian form on U which verifies certain compatibility conditions with respect to the associative product on U. The Riemannian and Ricci curvatures of the associated pseudo-K\"ahler metric are studied and a characterization of those Lie algebras which are Einstein but not Ricci flat is given. It is seen that all pseudo-K\"ahler Lie algebras can be inductively described by a certain method of double extensions applied to the associated complex asssociative commutative algebras

    Intensive Induction Chemotherapy Followed by Early High-Dose Therapy and Hematopoietic Stem Cell Transplantation Results in Improved Outcome for Patients with Hepatosplenic T-Cell Lymphoma: A Single Institution Experience

    Get PDF
    AbstractIntroductionHepatosplenic T-cell lymphoma is a rare form of extranodal non-Hodgkin lymphoma, first recognized as a distinct entity in the Revised European-American Lymphoma classification. Typical presentation includes lymphomatous infiltration of spleen and liver, and peripheral lymphadenopathy is rarely seen. The prognosis is almost uniformly poor, and there are no prospective studies of treatment of HSTCL.Patients and MethodsFor this report, we conducted a retrospective review of all pts who underwent treatment for HSTCL at our institution. Individual chart review was performed to report clinical presentation, management, and outcome.ResultsWe identified 14 pts with HSTCL managed at our center, 7 of which remain alive with median follow-up of 65.6 months. Six of 7 received alternative induction chemotherapy regimens such as ICE (ifosfamide, carboplatin, etoposide) or IVAC (ifosfamide, etoposide, high-dose cytarabine) as opposed to CHOP and all surviving pts had proceeded to undergo either autologous or allogeneic SCT.ConclusionOur results suggest that use of non-CHOP induction regimen and early use of high dose therapy and SCT consolidation may translate to improved survival for pts with HSTCL

    How does a cadaver model work for testing ultrasound diagnostic capability for rheumatic-like tendon damage?

    Get PDF
    To establish whether a cadaver model can serve as an effective surrogate for the detection of tendon damage characteristic of rheumatoid arthritis (RA). In addition, we evaluated intraobserver and interobserver agreement in the grading of RA-like tendon tears shown by US, as well as the concordance between the US findings and the surgically induced lesions in the cadaver model. RA-like tendon damage was surgically induced in the tibialis anterior tendon (TAT) and tibialis posterior tendon (TPT) of ten ankle/foot fresh-frozen cadaveric specimens. Of the 20 tendons examined, six were randomly assigned a surgically induced partial tear; six a complete tear; and eight left undamaged. Three rheumatologists, experts in musculoskeletal US, assessed from 1 to 5 the quality of US imaging of the cadaveric models on a Likert scale. Tendons were then categorized as having either no damage, (0); partial tear, (1); or complete tear (2). All 20 tendons were blindly and independently evaluated twice, over two rounds, by each of the three observers. Overall, technical performance was satisfactory for all items in the two rounds (all values over 2.9 in a Likert scale 1-5). Intraobserver and interobserver agreement for US grading of tendon damage was good (mean κ values 0.62 and 0.71, respectively), with greater reliability found in the TAT than the TPT. Concordance between US findings and experimental tendon lesions was acceptable (70-100 %), again greater for the TAT than for the TPT. A cadaver model with surgically created tendon damage can be useful in evaluating US metric properties of RA tendon lesions

    The Paradox and Continuum of Digital Disengagement: Denaturalising Digital Sociality and Technological Connectivity

    Get PDF
    This theoretical intervention puts forward a concept of ‘digital disengagement’ to discuss new socio-cultural, economic and political demarcations and implications surrounding the relationship between digital media, culture and society. At present, despite a proliferation of calls to reduce both the range of digital devices and communication platforms, and the time spent using them, and despite a growing body of academic work on disconnection or opt-out, disengagement from the digital is still conceptualised by media research as a spatiotemporal or an ideological aberration. To challenge this framework, we propose a paradigmatic shift. We invite digital media scholarship to denaturalise the digital by centring digital disengagement both as a complex phenomenon currently unfolding and as a conceptual entry point into thinking about sociality, agency, rights and everyday life more broadly. Mobilising digital disengagement as a theoretical lens, our piece provides the following: first, we critically assess the prevalent conflation of digitality with social networking, which leads to a limited understanding of disengagement as being only about disconnecting from social media platforms. Second, we challenge the normalisation of the technological in practices of disconnection, arguing instead that disengagement might be structured, but should not be determined, by the technological. Third, we demonstrate that digital disengagement is not a single phenomenon but a complex continuum of practices, motivations and effects. Understood as such, it has the potential to open new ways of imagining relations between technologies and freedoms, engagement and digitality and sociality and refusal

    Prognostic heterogeneity of adult B-cell precursor acute lymphoblastic leukaemia patients with t(1;19)(q23;p13)/TCF3-PBX1 treated with measurable residual disease-oriented protocols

    Get PDF
    The prognosis of t(1;19)(q23;p13)/transcription factor 3-pre-B-cell leukaemia homeobox 1 (TCF3-PBX1) in adolescent and adult patients with acute lymphoblastic leukaemia (ALL) treated with measurable residual disease (MRD)-oriented trials remains controversial. In the present study, we analysed the outcome of adolescent and adult patients with t(1;19)(q23;p13) enrolled in paediatric-inspired trials. The patients with TCF3-PBX1 showed similar MRD clearance and did not have different survival compared with other B-cell precursor ALL patients. However, patients with TCF3-PBX1 had a significantly higher cumulative incidence of relapse, especially among patients aged ≥35 years carrying additional cytogenetic alterations. These patients might benefit from additional/intensified therapy (e.g. immunotherapy in first complete remission with or without subsequent haematopoietic stem cell transplantation). 40 __ $u https://creativecommons.org/licenses/by-nc-nd/4.0

    Comparison between Spanish young and elderly people evaluated using Rivermead Behavioural Memory Test

    Get PDF
    The first objective of this work was to compare scores obtained in the daily memory function between young and elderly people, and to check whether there are differences between the groups for each of the profile scores obtained in the memory test. A second aim of this paper is to study the relationship between everyday memory and age, while controlling for gender and educational level. The total and profile scores obtained in the Rivermead Behavioural Memory Test were compared in a sample of 60 young and 120 elderly people from Valencia (Spain). Results showed significant differences between the two groups: those between 18 and 30 years obtained a higher average than those over 65. Once the group comparison was controlled for gender and educational level, the statistical effect of age group disappeared. The non-significant effect of group can not be explained by the introduction of gender, because both its main effect and the interaction were not statistically significant. However, educational level had a statistically significant effect which may explain the non-significant effect of group in this new analysis. The main conclusion is the need to carefully control for educational level in all studies related with everyday memory and ageing, as the differences found could be due to generational differences more than to biological deterioratio

    The fate and behavior of selected endocrine disrupting chemicals in full scale wastewater and sludge treatment unit processes

    Get PDF
    Endocrine disrupting chemicals are discharged into the environment mainly through wastewater treatment processes. There is a need for better understanding of the fate of these compounds in the unit processes of treatment plant to optimize their removal. The fate of oestrone, 17β-estradiol, 17α-ethinyestradiol and nonylphenol in the unit processes of full scale wastewater treatment plants in the UK, including activated sludge plant, oxidation ditch, biofilter and rotating biological contractor were investigated. The overall removal efficiencies of all the compounds ranged from 41 % to 100 %. The removals were predominantly during the secondary biological treatment with the rates of removal related to the nitrification rates and the sludge age. The removal efficiency of the treatment processes were in the order activated sludge > oxidation ditch > biofilter > rotating biological contractors. Activated sludge plant configured for biological nutrient removal showed better removal of the endocrine disrupting chemicals compared to conventional activated sludge plant effluents. Tertiary treatment was also significant in the removal process through solids removal. Overall mechanisms of removal were biodegradation and sorption unto sludge biomass. Phytoremediation was also significant in the removal processes. The endocrine disrupting chemicals persisted in the anaerobic sludge digestion process with percentage removals ranging fro 10-48 %. Sorption of the endocrine disrupting chemicals onto the sludge increased with increasing values for the partitioning coefficients and the organic carbon contents of the sludge

    Truncated Power Laws Reveal a Link between Low-Level Behavioral Processes and Grouping Patterns in a Colonial Bird

    Get PDF
    Background: Departures from power law group size frequency distributions have been proposed as a useful tool to link individual behavior with population patterns and dynamics, although examples are scarce for wild animal populations. Methodology/Principal Findings: We studied a population of Lesser kestrels (Falco naumanni) breeding in groups (colonies) from one to ca. 40 breeding pairs in 10,000 km 2 in NE Spain. A 3.5 fold steady population increase occurred during the eight-year study period, accompanied by a geographical expansion from an initial subpopulation which in turn remained stable in numbers. This population instability was mainly driven by first-breeders, which are less competitive at breeding sites, being relegated to breed solitarily or in small colony sizes, and disperse farther than adults. Colony size frequency distributions shifted from an initial power law to a truncated power law mirroring population increase. Thus, we hypothesized that population instability was behind the truncation of the power law. Accordingly, we found a power law distribution through years in the initial subpopulation, and a match between the power law breakpoint (at ca. ten pairs) and those colony sizes from which the despotic behavior of colony owners started to impair the settlement of newcomers. Moreover, the instability hypothesis was further supported by snapshot data from another population of Lesser kestrels in SW Spain suffering a population decline. Conclusions/Significance: Appropriate analysis of the scaling properties of grouping patterns has unraveled the lin

    Perturbative Instabilities on the Non-Commutative Torus, Morita Duality and Twisted Boundary Conditions

    Get PDF
    We study one-loop corrections in scalar and gauge field theories on the non-commutative torus. For rational theta, Morita equivalence allows these theories to be reformulated in terms of ordinary theories on a commutative torus with twisted boundary conditions. UV/IR mixing does not lead to singularities, however there can be large corrections. In particular, gauge theories show tachyonic instabilities for some of the modes. We discuss their relevance to spontaneous Z_N x Z_N symmetry breaking in the Morita dual SU(N) theory due to electric flux condensation.Comment: 30 page

    Ocean and coastal acidification off New England and Nova Scotia

    Get PDF
    Author Posting. © The Oceanography Society, 2015. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 28, no. 2 (2015): 182-197, doi:10.5670/oceanog.2015.41.New England coastal and adjacent Nova Scotia shelf waters have a reduced buffering capacity because of significant freshwater input, making the region’s waters potentially more vulnerable to coastal acidification. Nutrient loading and heavy precipitation events further acidify the region’s poorly buffered coastal waters. Despite the apparent vulnerability of these waters, and fisheries’ and mariculture’s significant dependence on calcifying species, the community lacks the ability to confidently predict how the region’s ecosystems will respond to continued ocean and coastal acidification. Here, we discuss ocean and coastal acidification processes specific to New England coastal and Nova Scotia shelf waters and review current understanding of the biological consequences most relevant to the region. We also identify key research and monitoring needs to be addressed and highlight existing capacities that should be leveraged to advance a regional understanding of ocean and coastal acidification.This project was supported in part by an appointment to the Internship/Research Participation Program at the Office of Water, US Environmental Protection Agency (EPA), administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the US Department of Energy and the EPA. JS acknowledges support from NASA grant from NNX14AL84G NASA-CCS
    • …
    corecore