Can acyclic conformational control be achieved via a sulfur-fluorine gauche effect?

The gauche conformation of the 1,2-difluoroethane motif is known to involve stabilising hyperconjugative interactions between donor (bonding, σC-H) and acceptor (antibonding, σ*C-F) orbitals. This model rationalises the generic conformational preference of F-Cβ-Cα-X systems (φFCCX ≈ 60°), where X is an electron deficient substituent containing a Period 2 atom. Little is known about the corresponding Period 3 systems, such as sulfur and phosphorus, where multiple oxidation states are possible. Conformational analyses of β-fluorosulfides, -sulfoxides and -sulfones are disclosed here, thus extending the scope of the fluorine gauche effect to the 3rd Period (F-C-C-S(O) n ; φFCCS ≈ 60°). Synergy between experiment and computation has revealed that the gauche effect is only pronounced in structures bearing an electropositive vicinal sulfur atom (S+-O-, SO2)

Improving the mesomorphic behaviour of supramolecular liquid crystals by resonance-assisted hydrogen bonding

A systematic structure-property relationship study on hydrogen-bonded liquid crystals was performed, revealing the impact of resonance-assisted hydrogen bonds (RAHBs) on the self-assembling behavior of the supramolecular architecture. The creation of a six-membered intramolecular hydrogen-bonded ring acts as a counterpart to the self-organization between hydrogen bond donators and acceptors and determines thus the suprastructure. Variation of the hydrogen-bonding pattern allowed us to significantly improve the temperature range of the reported liquid crystalline assemblies

Terminological approaches in the psychology of affectivity

Catedra de psihologie și management, Universitataea de Stat de Medicină și Farmacie „Nicolae Testemiţanu”, Chișinău, Republica Moldov

Plano de Negócio : Fast Grocer

O plano de negócio que se apresenta tem como objetivo proporcionar um serviço de entregas de bens alimentares a turistas, hospedes de alojamento local no Concelho de Cascais. Através deste projeto empreendedor, pretende-se que haja a criação de uma oferta de valor para o turista e que a sua experiência seja valorizada pelo mesmo. Considerando o total de investimento que ronda os €15.490 os fatores apresentados pelo projeto, como Valor Atual Liquido é de 169.637 €, Taxa Interna de Rentibilidade de 205,41%, e Pay Back período de 1 ano, critérios que garantem viabilidade económico-financeira deste projeto.The Business Plan presented is intended to provide a service of food deliveries to tourists, guests of local accommodation in Cascais. Through this entrepreneurial project, it is intended to create a value offer for the tourist and that their experience be valued by the same. Considering the total investment of around €15,490, the factors presented by the project, such as Net Current Value is € 169,637, Internal Rentibility Rate of 205.41%, and Pay Back period of 1 year, criteria that guarantee economic and financial viability to this project

Structural Chemistry of Copper(I) and Silver(I) Complexes with Triisopropylphosphane Sulfide, Selenide and Telluride Ligands

Phosphanchalkogenide sind von Bedeutung für die Koordination von Schwermetallen und den Aufbau und Abbau von Metallchalchogenid-Clustern (z. B. Fenske-Clustern), deren Eigenschaften zurzeit viel Beachtung finden. Hinsichtlich des Pearson-Konzeptes der harten und weichen Säuren und Basen, sollten Phosphantelluride (R3P=Te) ausgezeichnete Liganden gegenüber “weichen” Schwermetallkationen sein. Trotzdem sind sehr wenige Komplexe mit Phosphantellurid-Liganden in der Literatur bekannt. Zum Studium der Eingeschaften von Trialkylphosphantelluriden gegenüber Münzmetallen in der Lösung und im Festkörper wurden die Komplexe von Triisopropylphosphanchalkogeniden mit Kupfer(I), Silber(I) und Gold(I) untersucht. R3PTe-Cu(I) und R3PTe-Au(I) Komplexe (R=Me, iPr, tBu) wurden nur als intermediäre Spezies beobachtet, während die Silber(I)-Komplexe eine größere Stabilität mit zunehmenden Donoreigenschaften der R-Gruppe und abhängig von Natur des Anions aufweisen. Mit sehr schwach Nukleophilen (SbF6-Anion) bilden sich ionische und /oder supramolekulare Strukturen, während mit zunehmender Nukleophilie molekulare Strukturen erhalten wurden. Die besseren Donoreigenschaften von Tellur verglichen mit Schwefel oder Selen sind sehr gut in Komplexen mit Silber(I)-halogeniden zu beobachten. Der iPr3PTeAgI-Komplex zeigt in der Festkörperstruktur eine Tellur-Verbrückte Struktur, während iPr3PSAgCl-Komplex eine Chlor-Verbrückte Struktur mit terminalen Phosphansulfidliganden besitzt.With regard to the Pearson concept of hard and soft acids and bases, phosphane tellurides (R3P=Te) should be excellent ligands towards “soft” heavy metal cations. Their role as sources of phosphanes and of elemental tellurium allows them to contribute to the formation and decomposition of metal telluride clusters (like Fenske-typ coinage metal chalcogenide clusters), still R3P=Te complexes are extremely rare. To study the particular properties of the trialkylphosphane telluride ligands towards coinage metals in solution and in solid state, the coordination chemistry of triisopropylphosphane chalcogenides (iPr3PS, iPr3PSe and iPr3PTe) with silver(I), copper(I) and gold(I) salts was investigated. R3PTe-Cu(I) and Au(I) complexes (R = tBu, iPr, Me) are only transient species in solution, whereas in Ag(I) case, the basicity of R groups and the nature of the anion have an important role. The stability of complexes increases with increasing of R group branching. Less nucleophilic anions (SbF6 anion) led to the formation of ionic and/or supramolecular structures, while with increasing of anions nucleophilicity ([N(SO2CH3)2] or halides anions) molecular structures are obtained. The better donor proprieties of tellurium towards sulphur or selenium can be observed in the case of complexes with silver(I) halides. In the case of complex with phosphane telluride ligand iPr3PTeAgI a tellurium-bridge structure was obtain, while the complex iPr3PSAgCl shows in solid state a chlor-bridge structure with terminal phosphane sulphide ligands

Importance of studying medical sociology for future doctors

Catedra Economie, management şi psihopedagogie în medicină USMF „Nicolae Testemiţanu”Medical sociology is a branch of applied sociology, which began almost with the publication of "Le suicide. Etude of sociology "(1897) Durkheim's. Integrates medical sociology concepts, principles and research in medical sociology, including sociological education of medical students, the study of the health and social epidemiology, the study of development of a disease or the factors that influence patients' attitudes to illness (R. Strauss, 1972). Sociologia medicală este o ramură aplicativă a sociologiei, ce a debutat practic odată cu publicarea lucrării „Le suicide. Etude de sociologie“ (1897) a lui Durkheim. Sociologia în medicină integrează conceptele, principiile şi cercetările sociologice în medicină, inclusiv educaţia sociologică a studenţilor medicinişti, studiul comportamentului sanitar şi al epidemiologiei sociale, studiul proceselor de dezvoltare ale unei boli sau ale factorilor care influenţează atitudinea pacienţilor faţă de boală (R. Strauss, 1972)

Coping mechanisms function at the behavioral level

Catedra Economie, Management şi Psihopedagogie în medicină, USMF „Nicolae Testemiţanu”The article adaptive mechanisms have been elucidated in the psychological stress and comparative analysis of coping mechanisms and defenses. In order to understand the adaptive mechanisms in medical practice were described the psycho-behavioral risk types of patients: psycho-behavioral type A, type C. Also presented some 313 strategies appropriate psychotherapeutic patient needs and capabilities: experiential psychotherapy, cognitive behavioral psychotherapy, group psychotherapy etc. În articol au fost elucidate mecanismele adaptative în faţa stressului psihic şi analizate comparativ mecanismele de coping şi mecanismele defensive. În vederea cunoaşterii mecanismelor adaptative în practica medicală au fost descriese tipurile psihocomportamentale cu risc ale pacienţilor: tipul psihocomportamental A, tipul C. Deasemenea, au fost prezentate unele strategii psihoterapeutice adecvate necesităţilor şi posibilităţilor pacientului: psihoterapia experienţială, psihoterapia cognitiv-comportamentală, psihoterapia de grup, et

One electron oxidation of triferrocenylmethanol: Synthesis, metal atom dynamics, electron delocalization, and the crystal structure of [Fc 3COH]+ PF6 -

The title compound 2 was prepared and its crystal structure was determined at 100 K. The neat solid was examined by temperature dependent 57Fe Mössbauer effect (ME) spectroscopy over the interval 92 < T < 318 K, and evidences two diamagnetic Fe(II) sites and one paramagnetic Fe(III) site. The latter shows spin–lattice relaxation, but there is no evidence of electron delocalization among the three iron sites in the above temperature interval. The mean-square-amplitude-of-vibration of the diamagnetic iron site has been determined from the recoil-free fraction ME resonance, and compared to the neutral Fc3COH homologue (1). The ME dynamical data are in good agreement with the Ui,j value at 100 K extracted from the crystallographic results. The ME parameters at 5 K have also been determined with the sample compound embedded in a paraffin wax matrix as well as pelletized with BN