7 research outputs found

    The electron density of delocalized bonds (EDDB) applied for quantifying aromaticity

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    In this study the recently developed electron density of delocalized bonds (EDDB) is used to define a new measure of aromaticity in molecular rings. The relationships between bond-length alternation, electron delocalization and diatropicity of the induced ring current are investigated for a test set of representative molecular rings by means of correlation and principal component analyses involving the most popular aromaticity descriptors based on structural, electronic, and magnetic criteria. Additionally, a qualitative comparison is made between EDDB and the magnetically induced ring-current density maps from the ipsocentric approach for a series of linear acenes. Special emphasis is given to the comparative study of the description of cyclic delocalization of electrons in a wide range of organic aromatics in terms of the kekulean multicenter index KMCI and the newly proposed EDDBk indexThe research was supported in part by the Faculty of Chemistry at Jagiellonian University (grant K/DSC/001469, DS), Foundation for Polish Science (FNP START 2015, stipend 103.2015, DS), National Science Centre, Poland (NCN SONATA, grant 2015/17/ D/ST4/00558, DS) as well as the PL-Grid Infrastructure of the Academic Computer Centre CYFRONET with the calculations performed on the cluster platform ‘‘Prometheus’’. MS thanks for the support of the Ministerio de Economa y Competitividad of Spain (Project CTQ2014-54306-P), Generalitat de Catalunya (project number 2014SGR931, Xarxa de Refere`ncia en Qumica Teo`rica i Computacional, and ICREA Academia prize), and European Fund for Regional Development (FEDER grant UNGI10-4E-801

    Diagnostic difficulties and legal analysis of potential claims to occupational medicine specialists based on a case of unrecognizable cardiac angiosarcoma

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    Przedstawiono przypadek nagłego zgonu w miejscu pracy 56-letniej kobiety, którego przyczyną był rzadki pierwotny guz serca. Rodzina zmarłej złożyła doniesienie do prokuratury, sugerując udział osób trzecich w spowodowaniu zgonu lub nieprawidłowości w badaniu lekarskim poprzedzającym zgon. Przedstawiono przegląd dostępnych w bazach elektronicznych (m.in. Web of Science i PubMed) informacji klinicznych dotyczących naczyniakomięsaka serca przydatnych w praktyce lekarza medycyny pracy oraz analizę prawną potencjalnych roszczeń w stosunku do lekarza medycyny pracy w przypadku nierozpoznania nowotworu.The article presents a case of sudden death of a 56-year-old woman at the workplace, caused by a very rare primary cardiac tumor. The patient’s family reported a crime to the prosecutor’s office suggesting participation of third parties in causing the death or malpractice in physical examinations before the death. A review of clinical data concerning cardiac angiosarcoma, available in electronic databases (e.g., Web of Science, PubMed), was presented, which could be useful in the practice of occupational medicine specialists. A legal analysis of potential claims to occupational medicine specialist in the case of failure to recognize primary cardiac tumors was also included in the article

    Aromaticity of acenes : the model of migrating π\pi-circuits

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    The concept of migrating Clar's sextet is extended to explain the local aromaticity trends in linear acenes predicted by different aromaticity criteria from theoretical calculations as well as from experimental data. The electron density of delocalized bonds is used to assess the link between resonance and reactivity and to rationalize the constant-height AFM image of pentacen

    The role of the long-range exchange corrections in the description of electron delocalization in aromatic species

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    In this article, we address the role of the long-range exchange corrections in description of the cyclic delocalization of electrons in aromatic systems at the density functional theory level. A test set of diversified monocyclic and polycyclic aromatics is used in benchmark calculations involving various exchange-correlation functionals. A special emphasis is given to the problem of local aromaticity in acenes, which has been a subject of long-standing debate in the literature. The presented results indicate that the noncorrected exchange-correlation functionals significantly overestimate cyclic delocalization of electrons in heteroaromatics and aromatic systems with fused rings, which in the case of acenes leads to conflicting local aromaticity predictions from different criteriaThe research was supported in part by the Foundation for Polish Science (FNP START 2015, stipend 103.2015, DS), National Science Centre, Poland (NCN SONATA, grant 2015/17/D/ST4/ 00558, DS) as well as the PL-Grid Infrastructure of the Academic Computer Centre CYFRONET, with the calculations performed on cluster platforms Zeus and Prometheus. MS thanks for the support of the Ministerio de Economía y Competitividad of Spain (Project CTQ2014-54306-P), Generalitat de Catalunya (project number 2014SGR931, Xarxa de Referència en Química Teòrica i Computacional, and ICREA Academia prize), and European Fund for Regional Development (FEDER grant UNGI10-4E-801

    Uterine sarcoma – time is worth its weight in gold

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    Leiomyosarcoma is one of the most common types of soft tissue sarcoma in adults, and it can occur in almost any part of the body. Uterine leiomyosarcoma constitutes 1% of all gynaecological tumours. Most diagnosed sarcomas are not even suspected before surgery. However, in recent years, awareness of their presence in society has increased. Our case aims to draw attention to the need for better cooperation between pathologists and clinicians and reduce the time from suspicion of the disease to final diagnosis

    The role of the long-range exchange corrections in the description of electron delocalization in aromatic species

    No full text
    In this article, we address the role of the long-range exchange corrections in description of the cyclic delocalization of electrons in aromatic systems at the density functional theory level. A test set of diversified monocyclic and polycyclic aromatics is used in benchmark calculations involving various exchange-correlation functionals. A special emphasis is given to the problem of local aromaticity in acenes, which has been a subject of long-standing debate in the literature. The presented results indicate that the noncorrected exchange-correlation functionals significantly overestimate cyclic delocalization of electrons in heteroaromatics and aromatic systems with fused rings, which in the case of acenes leads to conflicting local aromaticity predictions from different criteriaThe research was supported in part by the Foundation for Polish Science (FNP START 2015, stipend 103.2015, DS), National Science Centre, Poland (NCN SONATA, grant 2015/17/D/ST4/ 00558, DS) as well as the PL-Grid Infrastructure of the Academic Computer Centre CYFRONET, with the calculations performed on cluster platforms Zeus and Prometheus. MS thanks for the support of the Ministerio de Economía y Competitividad of Spain (Project CTQ2014-54306-P), Generalitat de Catalunya (project number 2014SGR931, Xarxa de Referència en Química Teòrica i Computacional, and ICREA Academia prize), and European Fund for Regional Development (FEDER grant UNGI10-4E-801
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