6 research outputs found

    Black hole entropy in Loop Quantum Gravity

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    We calculate the black hole entropy in Loop Quantum Gravity as a function of the horizon area and provide the exact formula for the leading and sub-leading terms. By comparison with the Bekenstein-Hawking formula we uniquely fix the value of the 'quantum of area' in the theory.Comment: LaTeX, 10 page

    Synthesis and coordination chemistry of 2-(di-2-pyridylamino)pyrimidine; structural aspects of spin crossover in an Fe(II) complex

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    This paper was accepted on February 26 20122-(Di-2-pyridylamino)pyrimidine (L), a potentially ditopic tetradentate ligand, was synthesized from commercially available di-2-pyridylamine and 2-chloropyrimidine. Despite being capable of bridging two metal atoms with bidentate chelation of both metal centres, L prefers to chelate or bridge through the more basic pyridyl donors of the di-2-pyridylamine moiety. Mononuclear trans-[Fe(NCS)2(L)2] and [Cu(L)2(H2O)](BF4)2•H2O complexes, and a discrete [Ag2(L)4](PF6)2 metallomacrocycle were isolated and structurally characterized by X-ray crystallography. A mononuclear palladium complex [PdCl2(L)]•(solvate), where solvate = ½H2O or CH2Cl2, was also readily obtained in 71% yield. One example of the ligand acting as a bis(bidentate) bridging ligand was observed in a dinuclear [(PdCl2)2(L)]•¾H2O complex that was obtained only in very low yield (ca. 3%) from the reaction that produced [PdCl2(L)]•½H2O. trans-[Fe(NCS)2(L)2] undergoes a temperature dependent HS-LS (HS = high spin; LS = low spin) crossover at ca. 205 K that was 2 observed by X-ray crystallography and magnetic measurements and attempts were made to understand the structural basis of this process. Despite efforts to isolate examples of L bridging two iron(II) centres, only the mononuclear trans-[Fe(NCS)2(L)2] species could be obtained.Rachel S. Crees, Boujemma Moubaraki, Keith S. Murray, and Christopher J. Sumb

    PD-L1+ lung cancer stem cells modify the metastatic lymph-node immunomicroenvironment in nsclc patients

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    Introduction: Cancer stem cells (CSCs) are implicated in tumor initiation and development of metastasis. However, whether CSCs also affect the immune system is not fully understood. We investigated correlations between the PD-L1+ CSCs, changes in T-cell phenotype in metastatic and non-metastatic lymph nodes (LNs) and response to treatment. Methods: LNs’ aspirates were obtained during the EBUS/TBNA procedure of 20 NSCLC patients at different stages of the disease. CSCs and T-cell characteristics were determined by flow cytometry. Results: PD-L1+ CSCs positively correlated with the percentage of Tregs, PD-1+ CD4 T cells and Tim3+ CD4+ T cells, whereas PD-L1+ CSCs were negatively correlated with CD4+ T cells and CD28+ CD4+ T cells. The percentage of PD-L1+ CSCs was higher in patients with progressive disease (PD) as compared to patients with stable disease (SD) or partial response (PR). Among T cells, only PD-1+ CD4+ T cells and Tim3+ CD4+ T-cell frequencies were higher in patients with PD as compared to patients with SD or PR. Conclusion: The frequency of PD-L1+ CSCs associates with an altered T-cell frequency and phenotype indicating that CSCs can affect the immune system. The higher percentage of PD-L1+ CSCs in patients with PD may confirm their resistance to conventional therapy, suggesting that CSCs may be an interesting target for immunotherapy

    Exploring the Added Value of Women Health Care Managers in Poland

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    ABSTRACT Introduction: Female managers in the Polish health care system are seldom a subject of scientific investigation. Material and Methods: This study describes the share and profile of women in health care management positions and explores how and why Polish female health care managers add value to the leadership of health care organizations. Three data collection methods were used including: scoping review, analysis of data from governmental information bases and in-depth interviews with female health care managers. Results: Men comprise nearly twice the number of hospital directors in Poland as compared to women, or 67% of the total representation. Traits often attributed to women including strength, perseverance, multi-tasking, empathy, emotional intelligence and intuition add value in leadership roles. Polish women managers value the complementarity of genders in professional roles and their contribution to constructive collaboration. Conclusion: The study contributes to the scarce literature on Polish female health care managers. Keywords: health care management, female leadership, gender equity
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