329 research outputs found
On chains in -closed topological pospaces
We study chains in an -closed topological partially ordered space. We give
sufficient conditions for a maximal chain in an -closed topological
partially ordered space such that contains a maximal (minimal) element.
Also we give sufficient conditions for a linearly ordered topological partially
ordered space to be -closed. We prove that any -closed topological
semilattice contains a zero. We show that a linearly ordered -closed
topological semilattice is an -closed topological pospace and show that in
the general case this is not true. We construct an example an -closed
topological pospace with a non--closed maximal chain and give sufficient
conditions that a maximal chain of an -closed topological pospace is an
-closed topological pospace.Comment: We have rewritten and substantially expanded the manuscrip
Semigroups with operation-compatible Green’s quasiorders
We call a semigroup on which the Green’s quasiorder ≤ J (≤ L, ≤ R) is operation-compatible, a ≤ J-compatible (≤ L-compatible, ≤ R-compatible) semigroup. We study the classes of ≤ J-compatible, ≤ L-compatible and ≤ R-compatible semigroups, using the smallest operation-compatible quasiorders containing Green’s quasiorders as a tool. We prove a number of results, including the following. The class of ≤ L-compatible (≤ R-compatible) semigroups is closed under taking homomorphic images. A regular periodic semigroup is ≤ J-compatible if and only if it is a semilattice of simple semigroups. Every negatively orderable semigroup can be embedded into a negatively orderable ≤ J-compatible semigroup
Recommended from our members
Being cut off from social identity resources has shaped loneliness during the coronavirus pandemic: A longitudinal interview study with medically vulnerable older adults from the United Kingdom
Loneliness is a pernicious problem in older adulthood, associated with physical decline and isolation from valued social groups. However, the long‐term evolving experiences of ageing, identity and loneliness have yet to be elucidated. We use a Qualitative Longitudinal Research interview approach with nine vulnerable older adults (Agemean = 79.4 years), in which five participants were interviewed twice between 2019 and 2020, and four participants were interviewed at three‐time points from 2019 to 2021. This study aims to understand the unfolding experiences of ageing, social identity and loneliness during a prolonged period of social isolation during the Coronavirus pandemic. A theoretically guided thematic analysis highlights that participants initially experience ‘Categorisation as Vulnerable and Loss of Agency’ and ‘Shrinking Social Worlds’, leading to ‘Undermining of Reciprocal Support’ and ‘Fears of Persistent Loneliness’. Findings suggest that interventions to ameliorate loneliness among older adults would benefit from addressing age‐based stereotypes and emphasising the value of reciprocal contributions that older adults can make to their networks, as well as scaffolding and enhancing social identification with new groups. Please refer to the Supplementary Material section to find this article's Community and Social Impact Statement
Green's relations and stability for subsemigroups
We prove new results on inheritance of Green's relations by subsemigroups in the presence of stability of elements. We provide counterexamples in other cases to show in particular that not all right-stable semigroups are embeddable in left-stable semigroups. This is carried out in the context of a survey of the various closely related notions of stability and minimality of Green's classes that have appeared in the literature over the last sixty years, and which have sometimes been presented in different forms
Symmetry structure in discrete models of biochemical systems : natural subsystems and the weak control hierarchy in a new model of computation driven by interactions
© 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.Interaction Computing (IC) is inspired by the observation that cell metabolic/regulatory systems construct order dynamically, through constrained interactions between their components and based on a wide range of possible inputs and environmental conditions. The goals of this work are (1) to identify and understand mathematically the natural subsystems and hierarchical relations in natural systems enabling this, and (2) to use the resulting insights to define a new model of computation based on interactions that is useful for both biology and computation. The dynamical characteristics of the cellular pathways studied in Systems Biology relate, mathematically, to the computational characteristics of automata derived from them, and their internal symmetry structures to computational power. Finite discrete automata models of biological systems such as the lac operon, Krebs cycle, and p53-mdm2 genetic regulation constructed from Systems Biology models have canonically associated algebraic structures { transformation semigroups. These contain permutation groups (local substructures exhibiting symmetry) that correspond to "pools of reversibility". These natural subsystems are related to one another in a hierarchical manner by the notion of "weak control ". We present natural subsystems arising from several biological examples and their weak control hierarchies in detail. Finite simple non-abelian groups (SNAGs) are found in biological examples and can be harnessed to realize nitary universal computation. This allows ensembles of cells to achieve any desired finitary computational transformation, depending on external inputs, via suitably constrained interactions. Based on this, interaction machines that grow and change their structure recursively are introduced and applied, providing a natural model of computation driven by interactions.Peer reviewe
New Role for Cdc14 Phosphatase: Localization to Basal Bodies in the Oomycete Phytophthora and Its Evolutionary Coinheritance with Eukaryotic Flagella
Cdc14 protein phosphatases are well known for regulating the eukaryotic cell cycle, particularly during mitosis. Here we reveal a distinctly new role for Cdc14 based on studies of the microbial eukaryote Phytophthora infestans, the Irish potato famine agent. While Cdc14 is transcribed constitutively in yeast and animal cells, the P. infestans ortholog is expressed exclusively in spore stages of the life cycle and not in vegetative hyphae where the bulk of mitosis takes place. PiCdc14 expression is first detected in nuclei at sporulation, and during zoospore formation the protein accumulates at the basal body, which is the site from which flagella develop. The association of PiCdc14 with basal bodies was supported by co-localization studies with the DIP13 basal body protein and flagellar β-tubulin, and by demonstrating the enrichment of PiCdc14 in purified flagella-basal body complexes. Overexpressing PiCdc14 did not cause defects in growth or mitosis in hyphae, but interfered with cytoplasmic partitioning during zoosporogenesis. This cytokinetic defect might relate to its ability to bind microtubules, which was shown using an in vitro cosedimentation assay. The use of gene silencing to reveal the precise function of PiCdc14 in flagella is not possible since we showed previously that silencing prevents the formation of the precursor stage, sporangia. Nevertheless, the association of Cdc14 with flagella and basal bodies is consistent with their phylogenetic distribution in eukaryotes, as species that lack the ability to produce flagella generally also lack Cdc14. An ancestral role of Cdc14 in the flagellar stage of eukaryotes is thereby proposed
Prevalence of Human Papilloma Virus Infections and Cervical Cytological Abnormalities among Korean Women with Systemic Lupus Erythematosus
We performed a multicenter cross-sectional study of 134 sexually active systemic lupus erythematosus (SLE) patients to investigate the prevalence of and risk factors for high risk human papilloma virus (HPV) infection and cervical cytological abnormalities among Korean women with SLE. In this multicenter cross-sectional study, HPV testing and routine cervical cytologic examination was performed. HPV was typed using a hybrid method or the polymerase chain reaction. Data on 4,595 healthy women were used for comparison. SLE patients had greater prevalence of high-risk HPV infection (24.6% vs. 7.9%, P<0.001, odds ratio 3.8, 95% confidence interval 2.5-5.7) and of abnormal cervical cytology (16.4 vs. 2.8%, P<0.001, OR 4.4, 95% CI 2.5-7.8) compared with controls. SLE itself was identified as independent risk factors for high risk HPV infection among Korean women (OR 3.8, 95% CI 2.5-5.7) along with ≥2 sexual partners (OR 8.5, 95% CI 1.2-61.6), and Pap smear abnormalities (OR 97.3, 95% CI 6.5-1,456.7). High-risk HPV infection and cervical cytological abnormalities were more common among Korean women with SLE than controls. SLE itself may be a risk factor for HPV infection among Korean women, suggesting the importance of close monitoring of HPV infections and abnormal Pap smears in SLE patients
Bodies of emotion: rethinking culture and emotion through Southeast Asia
Feelings are not substances to be discovered in our blood but social practices organized by stories that we both enact and tell. michelle rosaldo 1984:14
A functional AT/G polymorphism in the 5'-untranslated region (UTR) of SETDB2 in the IgE locus on human chromosome 13q14
The immunoglobulin E (IgE)-associated locus on human chromosome 13q14 influencing asthma-related traits contains the genes PHF11 and SETDB2. SETDB2 is located in the same linkage disequilibrium region as PHF11 and polymorphisms within SETDB2 have been shown to associate with total serum IgE levels. In this report, we sequenced the 15 exons of SETDB2 and identified a single previously ungenotyped mutation (AT/G, rs386770867) in the 5′-untranslated region of the gene. The polymorphism was found to be significantly associated with serum IgE levels in our asthma cohort (P=0.0012). Electrophoretic mobility shift assays revealed that the transcription factor Ying Yang 1 binds to the AT allele, whereas SRY (Sex determining Region Y) binds to the G allele. Allele-specific transcription analysis (allelotyping) was performed in 35 individuals heterozygous for rs386770867 from a panel of 200 British families ascertained through probands with severe stage 3 asthma. The AT allele was found to be significantly overexpressed in these individuals (P=1.26 × 10(−21)). A dual-luciferase assay with the pGL3 luciferase reporter gene showed that the AT allele significantly affects transcriptional activities. Our results indicate that the IgE-associated AT/G polymorphism (rs386770867) regulates transcription of SETDB2
Cost effectiveness of support for people starting a new medication for a long term condition through community pharmacies: an economic evaluation of the New Medicine Service (NMS) compared with normal practice
Background: The English community pharmacy New Medicine Service (NMS) significantly increases patient adherence to medicines, compared with normal practice. We examined the cost-effectiveness of NMS compared with normal practice by combining adherence improvement and intervention costs with the effect of increased adherence on patient outcomes and healthcare costs.
Methods: We developed Markov models for diseases targeted by the NMS (hypertension, type 2 diabetes, chronic obstructive pulmonary disease, asthma and antiplatelet regimens) to assess the impact of patients’ non-adherence. Clinical event probability, treatment pathway, resource-use and costs were extracted from literature and costing tariffs. Incremental costs and outcomes associated with each disease were incorporated additively into a composite probabilistic model and combined with adherence rates and intervention costs from the trial. Costs per extra quality-adjusted-life-year(QALY) were calculated from the perspective of NHS England, using a lifetime horizon.
Results: NMS generated a mean of 0.05 (95%CI: 0.00, 0.13) more QALYs per patient, at a mean reduced cost of -£144 (95%CI: -769, 73). The NMS dominates normal practice with probability of 0.78 (ICER: - £3166 per QALY). NMS has a 96.7% probability of cost-effectiveness compared with normal practice at a willingness-to-pay of £20000 per QALY. Sensitivity analysis demonstrated that targeting each disease with NMS has a probability over 0.90 of cost-effectiveness compared with normal practice at a willingness-to-pay of £20000 per QALY.
Conclusions: Our study suggests that the New Medicine Service increased patient medicine adherence compared with normal practice, which translated into increased health gain at reduced overall cost
- …