665 research outputs found

    4,4′-Bipyridinium bis­(oxalato-κ2 O 1,O 2)cuprate(II): an ion-pair complex

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    The title compound, (C10H10N2)[Cu(C2O4)2] or (4,4′-H2bpy)[Cu(ox)2] (bpy is 4,4′-bipyridine and ox is oxalate), is an ion-pair complex comprising a protonated 4,4′-bipyridinium dication and a square-planar dioxalatocopper(II) dianion. In the centrosymmetric dianion, the CuII centre is coordinated by four O atoms from the two dicrete oxalate ligands [Cu—O = 1.9245 (19) and 1.9252 (17) Å], while the planar dications are also centrosymmetric. Inter-species N—H⋯O hydrogen bonds link the cations and anions into one-dimensional chains and, together with weak intra-ion C—H⋯O inter­actions, give a two-dimensional sheet structure

    FERI: A Multitask-based Fairness Achieving Algorithm with Applications to Fair Organ Transplantation

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    Liver transplantation often faces fairness challenges across subgroups defined by sensitive attributes like age group, gender, and race/ethnicity. Machine learning models for outcome prediction can introduce additional biases. To address these, we introduce Fairness through the Equitable Rate of Improvement in Multitask Learning (FERI) algorithm for fair predictions of graft failure risk in liver transplant patients. FERI constrains subgroup loss by balancing learning rates and preventing subgroup dominance in the training process. Our experiments show that FERI maintains high predictive accuracy with AUROC and AUPRC comparable to baseline models. More importantly, FERI demonstrates an ability to improve fairness without sacrificing accuracy. Specifically, for gender, FERI reduces the demographic parity disparity by 71.74%, and for the age group, it decreases the equalized odds disparity by 40.46%. Therefore, the FERI algorithm advances fairness-aware predictive modeling in healthcare and provides an invaluable tool for equitable healthcare systems

    Newly identified NO-sensor guanylyl cyclase/connexin 43 association is involved in cardiac electrical function

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    Background: Guanylyl cyclase, a heme-containing alpha 1 beta 1 heterodimer (GC1), produces cGMP in response to Nitric oxide (NO) stimulation. The NO-GC1-cGMP pathway negatively regulates cardiomyocyte contractility and protects against cardiac hypertrophy-related remodeling. We recently reported that the beta 1 subunit of GC1 is detected at the intercalated disc with connexin 43 (Cx43). Cx43 forms gap junctions (GJs) at the intercalated disc that are responsible for electrical propagation. We sought to determine whether there is a functional association between GC1 and Cx43 and its role in cardiac homeostasis. Methods and Results: GC1 and Cx43 immunostaining at the intercalated disc and coimmunoprecipitation from membrane fraction indicate that GC1 and Cx43 are associated. Mice lacking the alpha subunit of GC1 (GC alpha 1 knockout mice) displayed a significant decrease in GJ function (dye-spread assay) and Cx43 membrane lateralization. In a cardiac-hypertrophic model, angiotensin II treatment disrupted the GC1-Cx43 association and induced significant Cx43 membrane lateralization, which was exacerbated in GC alpha 1 knockout mice. Cx43 lateralization correlated with decreased Cx43-containing GJs at the intercalated disc, predictors of electrical dysfunction. Accordingly, an ECG revealed that angiotensin II-treated GCa1 knockout mice had impaired ventricular electrical propagation. The phosphorylation level of Cx43 at serine 365, a protein-kinase A upregulated site involved in trafficking/assembly of GJs, was decreased in these models. Conclusions: GC1 modulates ventricular Cx43 location, hence GJ function, and partially protects from electrical dysfunction in an angiotensin II hypertrophy model. Disruption of the NO-cGMP pathway is associated with cardiac electrical disturbance and abnormal Cx43 phosphorylation. This previously unknown NO/Cx43 signaling could be a protective mechanism against stress-induced arrhythmia

    Melaka and its Past

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    Despite the celebration and promotion of the creative economy, there is still a “dark” side to creativity. Creativity entails experimentation, chaos and failures. A creative space blends the aesthetics with chaos, sleek design with experimentation, and economic development with failed ideas. This case looks at the ambiguous and ambivalent interfaces of history in the historical city of Melaka (also known as Malacca) in Malaysia. History, by its definition, is a documentation of the past. Any historical documentation can be contested and revised. This case will not engage in the debate on revisionist history. Instead, it will show how history and heritage is negotiated and appropriated under present circumstances in the historic city of Melaka. The re‐interpretation and revision of history is part of the everyday creative response to changing circumstances. Such contemporary responses to the past, however unclear and acrimonious, are the essence of a creative place

    Bis(2-amino­thia­zole-4-acetato)aquazinc(II)

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    In the title compound, [Zn(C5H5N2O2S)2(H2O)], the central Zn atom (2 site symmetry) is five-coordinated by two N and three O atoms [Zn—N = 2.047 (3) Å, Zn—O = 2.099 (2) and 1.974 (4) Å] in a distorted square-pyramidal geometry. Besides one O atom from a water mol­ecule, two 2-amino­thia­zole-4-acetate ligands provide two N and two O atoms as coordinated atoms. In the crystal structure, inter­molecular O—H⋯O and N—H⋯O hydrogen bonds connect the mol­ecules into an infinite three-dimensional framework

    National and local politics in branding the past

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    This paper critically examines the relationship between federal and local‐state level governments in interpreting and presenting the World Heritage brand at two Malaysian World Heritage sites, George Town and Melaka. The World Heritage status is internationally recognised. Although the World Heritage brand offers many advantages in tourism development and destination marketing, what and how the local heritage is conserved, interpreted and appreciated remains open. This article shows that the mechanisms of interpreting and presenting the WH status vary according to the agendas and needs of authorities. This working paper also shows that material heritage and heritage stories are highly politicized, and the World Heritage recognition has inevitably become a tool for further ideological intentions

    Simulating the collapse transition of a two-dimensional semiflexible lattice polymer

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    It has been revealed by mean-field theories and computer simulations that the nature of the collapse transition of a polymer is influenced by its bending stiffness ϵb\epsilon_{\rm b}. In two dimensions, a recent analytical work demonstrated that the collapse transition of a partially directed lattice polymer is always first-order as long as ϵb\epsilon_{\rm b} is positive [H. Zhou {\em et al.}, Phys. Rev. Lett. {\bf 97}, 158302 (2006)]. Here we employ Monte Carlo simulation to investigate systematically the effect of bending stiffness on the static properties of a 2D lattice polymer. The system's phase-diagram at zero force is obtained. Depending on ϵb\epsilon_{\rm b} and the temperature TT, the polymer can be in one of three phases: crystal, disordered globule, or swollen coil. The crystal-globule transition is discontinuous, the globule-coil transition is continuous. At moderate or high values of ϵb\epsilon_{\rm b} the intermediate globular phase disappears and the polymer has only a discontinuous crystal-coil transition. When an external force is applied, the force-induced collapse transition will either be continuous or discontinuous, depending on whether the polymer is originally in the globular or the crystal phase at zero force. The simulation results also demonstrate an interesting scaling behavior of the polymer at the force-induced globule-coil transition.Comment: 16 page

    Bis(2-amino-4-methyl-1,3-thia­zole-κN 3)dichloridocadmium(II)

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    In the title compound, [CdCl2(C4H6N2S)2], the CdII atom is coordinated by two chlorido ligands and two N atoms of the 2-amino-5-methyl-1,3-thia­zole (amtz) ligands in a slightly distorted tetra­hedral coordination geometry. Intra- and inter­molecular N—H⋯Cl hydrogen bonding stabilizes the crystal structure. A weak S⋯Cl inter­action [3.533 (2) Å] is observed between neighboring mol­ecules
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