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Electronic Word of Mouth Communications : character and determinants of its persuasiveness
No full textBEST-CSP benchmark study of polymorphs I and II of sulfamerazine and the perils of polytype polymorphs
No full textWe report the outcome of an interdisciplinary investigation, by the BEST-CSP network, of the kinetically favored form I and the low-temperature stable form II polymorphs of the drug sulfamerazine (SMZ). Form II can be reproducibly obtained by slurrying in acetonitrile(MeCN)/water at room temperature, though seeding with form II significantly speeds up the conversion. New structure determinations have been obtained for both forms over a wide temperature range, with both single crystal and powder X-ray diffraction methods. Room temperature FT-IR and solid-state NMR spectra are provided. The enantiotropic but practically irreversible crystal-to-crystal transition from form II to form I is observed at temperatures ranging from 150 to 170 °C in various differential scanning calorimetry (DSC) experiments, depending on sample and heating rate. The enthalpy of transition at 150 °C is measured as . The differences in the heat capacities mean that the DSC measured enthalpies vary with the onset temperature by about over the range of heating rates commonly used in DSC experiments. Attempts to find the solvent-mediated transition temperature were complicated by observing that slurrying experiments in both methanol and above 50 °C produce a new, late-identified polymorph, sulfamerazine form V, which is closely related to form I but with an alternative packing of the double layers, i.e., is a polytype polymorph. Forms I and V are only easily distinguishable by high-quality powder X-ray diffraction. Form V appears to be marginally more stable than form I across the temperature range studied. The experimental data, including heat capacities and thermal expansion rates, are used to test a wide range of assumptions and energy models for calculating free energy differences between these polymorphs, illustrating the challenges in computationally modeling the thermodynamic transition temperature between form I and II. The implications of the discovery of form V on establishing the phase diagram of sulfamerazine are discussed
Funkcjonalizacja powierzchni materiałów węglowych za pomocą plazm : właściwości elektronowe, zwilżalność i odpowiedzi biologiczne
No full textPrognostic significance of the discrepancy between STEMI/NSTEMI paradigm and the angiographically confirmed diagnosis of Occlusion Myocardial Infarction : a retrospective cohort study
No full textCorrelates of suicide attempts in young people in India – a case-control study of persons admitted to a hospital in Pune
No full textCirculation of judgments between EU Member States and China : a path through complicated framework examined on the example of Poland
No full textResidual intersections and Schubert varieties
No full textInspired by the work of Ulrich [26] and Huneke–Ulrich [25], we
describe a pattern to show that the ideals of certain opposite
embedded Schubert varieties (defined by this pattern) arise
by taking residual intersections of two (geometrically linked)
opposite Schubert varieties which we call Ulrich pair. This
pattern is uniform for the ADE types. Some of the free
resolutions of the Schubert varieties in question are important
for the structure of finite free resolutions. Our proof is
representation theoretical and uniform for our pattern,
however it is possible to derive our results using case-by-case
analysis and the aid of a computer
A PD-1/PD-L1-sensitive Co-culture-based primary T-cell activation assay
No full textProgrammed cell death protein 1 (PD-1) is crucial in inhibiting immune responses by modulating the activity of T cells. We present an in vitro assay that is based on a co-culture of primary immune cells represented by human peripheral blood mononuclear cells (PBMCs), isolated from healthy donors with Chinese hamster ovary-derived cell line (CHO-K1) overexpressing human PD-L1 protein (hPD-L1) and an artificial TCR-activator construct (TCRAct). CHO-K1/TCRAct/hPD-L1 cells mimic antigen-presenting cells by activating T cells via the T-cell receptor (TCR) and providing a ligand for the negative immune checkpoint (PD-L1 protein). The two components, PBMCs and CHO-K1/TCRAct/hPD-L1 cells, when in co-culture, provide a T-cell activation (TCA) assay, which may be used to test the potency of molecules targeting the PD-1/PD-L1 immune checkpoint. This method relies on monitoring the activation of helper CD4+ and cytotoxic CD8+ T cells using flow cytometry by analyzing the expression levels of early (CD69), intermediate (CD25 and HLA-DR), and late (PD-1) activation/exhaustion markers. This is the well-established in vitro co-culture assay in which primary T-cell activation via the TCR is diminished by the concurrent presence of PD-1/PD-L1 immune checkpoint, which can be blocked resulting in increased expression of T-cell surface markers
