(Hydroxyphenyl)oxazoline: a Novel and Remarkably Facile Entry into the Area of Chiral Cationic Alkylzirconium Complexes Which Serve as Polymerization Catalysts

How can the entry into the area of chiral cationic alkyl derivatives of group 4 metals be simplified? We succeeded in, using readily available amino alcohols, which have been converted into chiral (hydroxyphenyl)oxazolines. These compounds have been employed in the organometallic derivatization of early transition metals

Quality of life in liver transplant recipients during the Corona virus disease 19 pandemic: A multicentre study

Background: Liver transplant recipients require specific clinical and psychosocial attention given their frailty. Main aim of the study was to assess the quality of life after liver transplant during the current pandemic. Methods: This multicentre study was conducted in clinically stable, liver transplanted patients. Enrollment opened in June and finished in September 2021. Patients completed a survey including lifestyle data, quality of life (Short Form health survey), sport, employment, diet. To examine the correlations, we calculated Pearson coefficients while to compare subgroups, independent samples t-tests and ANOVAs. To detect the predictors of impaired quality of life, we used multivariable logistic regression analysis. Results: We analysed data from 511 patients observing significant associations between quality of life’s physical score and both age and adherence to Mediterranean diet (p <.01). A significant negative correlation was observed between mental score and the sedentary activity (p <.05). Female patients scored significantly lower than males in physical and mental score. At multivariate analysis, females were 1.65 times more likely to report impaired physical score than males. Occupation and physical activity presented significant positive relation with quality of life. Adherence to Mediterranean diet was another relevant predictor. Regarding mental score, female patients were 1.78 times more likely to show impaired mental score in comparison with males. Sedentary activity and adherence to Mediterranean diet were further noteworthy predictors. Conclusions: Females and subjects with sedentary lifestyle or work inactive seem to show the worst quality of life and both physical activity and Mediterranean diet might be helpful to improve it

Longitudinal changes in amygdala, hippocampus and cortisol development following early caregiving adversity

Decades of research have shown long-term effects of early caregiving adversity on stress physiology and limbic brain regions, two key biological systems that are implicated in risk for internalizing disorders. Although stress physiology and limbic brain structure undergo significant maturational change during childhood and adolescence, and reciprocally influence each other, the effects of early caregiving adversity on these developmental processes is not well understood. In the current study, we used an accelerated longitudinal design to assess the development of stress physiology, amygdala, and hippocampal volume following early institutional care. Previously Institutionalized (PI; N = 93) and comparison (COMP; N = 161) youth (ages 4-20 years old) completed 1-3 waves of data collection, each spaced approximately 2 years apart, for diurnal cortisol (N = 239, providing a total of 380 diurnal datasets), structural MRI (N = 156, providing a total of 306 scans) and parent-reported internalizing symptoms (N = 133, providing a total of 227 time points). We observed a developmental shift in morning cortisol in the PI group, with blunted levels in childhood and heightened levels in late adolescence. PI history was associated with reduced hippocampal volume and reduced growth of the amygdala, resulting in smaller volumes by adolescence. Results also suggested feed-forward brain-to-hormone mechanisms, such that both amygdala and hippocampal volumes were prospectively associated with morning cortisol levels two years later. Finally, amygdala and hippocampal volumes were independently associated with internalizing scores across the entire sample. These results indicate that adversity-related physiological and neural phenotypes are not stationary during development but instead exhibit dynamic and interdependent changes from early childhood to early adulthood

Heightened perception: Donald Judd, John Chamberlain, Robert Irwin, and Larry Bell, 1960-1975

textThis dissertation explains how and why some American artists investigated visual phenomena and heightened perception during the 1960s and 1970s. As an analytical account grounded in the perceptual experience of artworks and in archival research of the claims artists made for their creations, this study is centered around the themes of re-sensitizing one’s body and perceptual faculties, the process of empirical discovery, and the ultimate inability of language to satisfactorily describe sensory phenomena. In Chapter 1, I establish a brief intellectual history of research concerning the sensory faculties from fields in the humanities, including psychology, philosophy, and art history. In Chapter 2, I analyze Judd’s art-critical concept of optical phenomena and consider the art about which he wrote, including his own, on the basis of this tentative classification. In Chapter 3, I evaluate John Chamberlain’s lacquer paintings in terms of the visual phenomena generated by his innovative paint mixtures and application techniques, then consider his provisional separation of intuition and intellect. In Chapter 4, I examine Robert Irwin’s efforts to refine his visual attentiveness and, in the course of doing so, I also test the accompanying artworks he made that demand such unusually acute observation. In Chapter 5, I argue that distinguishing physical, pictorial, and reflected visual phenomena in Larry Bell’s pieces proves to be an exceptional challenge, a problem compounded by the inefficacy of trying to communicate visual discoveries using language. In the Conclusion, I demonstrate that by restoring the role of heightened perception and sensory discovery to the history of art of the 1960s and 1970s, this dissertation helps to preserve the complexity and variety of works made during that time.Art and Art Histor

Zirconium meso-Octaethylporphyrinogen as Carrier for Sodium Hydride in Toluene: Zirconium-Sodium Bimetallic Hydride and Alkyls

The reaction of the tetralithium meso-octaethylporphyrinogen Et8N4Li4(THF)4 (2) with ZrCl4(THF)2 led to the formation of [(eta5-eta1-eta5-eta1-Et8N4)Zr(THF)] (3), containing two eta5 and two eta1 pyrrolyl anions bonded to zirconium. Such a complex acts as a bifunctional acid-base system able to dissolve ionic salts in their monomeric or dimeric form in hydrocarbon solution. The reaction of 3 with NaH in toluene led to the complexation of NaH via the interaction of the hydride with the Lewis acid Zr and the eta5 complexation of Na by the pyrrolyl anions in [{eta5-eta1-eta1-eta1-Et8N4)-Zr}2(mu-NaH)2] (4). Complex 4 reacts with terminal olefins in toluene by inserting the C=C double bond in the Zr-H functionality and so forming, in the case of ethylene, [{eta5-eta1-eta1-eta1-Et8N4)Zr(CH2CH3)}2(mu-Na)2] (5) and, in the case of 1-hexene, [{eta5-eta1-eta1-eta1-Et8N4)Zr(CH2(CH2)4CH3)}2(mu-Na)2] (6). Similarly, 4 adds to PhC=CH, which leads to the corresponding vinyl complex [(eta5-eta1-eta1-eta1-Et8N4)Zr-trans-(CH=CHPh)]2 (7). The dimeric structure of 4 remains intact after the reaction giving 5-7, however, in these products, major differences in the Na-porphyrinogen interaction modes can be seen. The reaction of 4 with C2H4 in THF led to a Zr-H porphyrinogen monomeric species identical to that formed from dissolving 5 in THF, [{(eta5-eta1-eta1-eta1-Et8N4)Zr(CH2CH3)}{Na(THF)2}] (8). Crystallographic details: 3 orthorhombic, space group Pbcn, a = 12.935(3) angstrom, b = 12.704(3) angstrom, c = 21.649(3) angstrom, alpha = beta = gamma 90-degrees, Z = 4, R = 0.037; 4 monoclinic, space group C2/c, a = 24.272(3) angstrom, b = 12.640(4) angstrom, c = 21.886(3) angstrom, alpha = gamma = 90-degrees, beta = 101.75(1)degrees, Z = 4, R = 0.053; 5 triclinic, space group P1BAR, a = 11.565(2) angstrom, b = 12.598(2) angstrom, c = 14.327(2) angstrom, alpha = 100.30(1)degrees, beta = 103.65(1)degrees, gamma = 113.73(1)degrees, Z = 1, R = 0.034; 7 monoclinic, space group P2(1)/c, a = 13.815(2) angstrom, b = 24.619(2) angstrom, c = 13.981(2) angstrom, alpha = gamma = 90-degrees, beta = 108.73(1)degrees, Z = 2, R = 0.047; 8 monoclinic, space group P2(1)/c, a = 11.264(1) angstrom, b = 19.646(4) angstrom, c = 20.609(3) angstrom, alpha = gamma = 90-degrees, beta = 101.18(2)degrees, Z = 4, R = 0.042

Reaction of Metal Carbonyls with Naked Enolates to Make a Metallocarbene Enolate and Alkylcarbonylmetalates

The KH-mediated deprotonation of acetophenone and propiophenone in THF led to the ion-pair and naked forms of the following crystalline enolates in good yield: ArC(CH2)0 ... K-(18-crown-6) [Ar = Ph, 4; 2-MeOC6H4, 5; 1,3,5-Me3C6H2,6], [PhC(CH2)0][K(kryptofix-2,2,2)], 7, and [PhC(--CHMe)O ... K(18-crown-6)], 8. The reaction of ion-pair 4 with [Cr(CO)5(THF)] led to the isolation of an alkylcarbonylmetalate, 9, [PhC(O)CH2Cr(CO)4CO ... K(18-crown-6)]n, a crystalline polymer in which the [PhC(O)CH2Cr(CO)5]- anion is bridged by [K(18-crown-6)]+ via the oxygen of the enolate and one of the carbonyl oxygens. The protonation of the Fischer carbene [(CO)5Cr=C(OMe)Me], 10, led to an alkylcarbonylmetalate analogue of 9. The X-ray analysis of [CH2(OMe)CCr(CO)4CO ... K(18-crown-6)], 11, revealed a decrease in the Cr-C(carbene) bond distance, and electron transfer from the anionic carbene to the trans CO. The trans Cr-C-0 has an increased Cr-C bond length, a decreased C-O bond length, and a Cr-C-O angle of 159.7(6)-degrees. The reaction of 4 with [Cr(CO)6] led to a Fischer-type metallacarbene, 12, from attack of the enolate on carbon monoxide; 12 was deprotonated by starting material to a dianionic metallacarbene enolate [(CO)5Cr--C(O-)CH=C(O-)Ph], 13. The alkylation and silylation of 13 led to the corresponding alkylated and silylated forms of 13, [(CO)5Cr=C(OMe)-CH=C-(OMe)Ph], 16, and [(CO)5Cr=C(OSiR2R')-CH=C(OSiR2R')Ph] [R = R' = Me, 17; R = Me, R' = Bu(t), 18]. An analogous metallacarbene enolate and its silylated form have been obtained for tungsten, [(CO)5W=C(O-)CH=C(O-)Ph ... {K(18-crown-6)}2], 19, and [ (CO)5W=C(OSiMe3)-CH=C(OSiMe3)Ph], 20. The reaction of the naked enolate 7 and [Cr(CO)6] led to a metallacarbene enolate which, due to the absence of stabilization by ion-pair formation, is much less stable than 13 or 19. Crystallographic details are as follows: 4 is monoclinic, space group P2(1)/n, a = 10.109(1) angstrom, b = 9.041(1) angstrom, c = 24.935(2) angstrom, beta = 96.94(l)-degrees, Z = 4, and R = 0.053; 7 is monoclinic, space group P2/n, a = 17.473(2) angstrom, b = 10.615(1) angstrom, c = 16.133(2) angstrom, beta = 99.75(1)-degrees, Z = 4, and R 0.040; 8 is monoclinic, space group P2(1)/c, a = 14.285(3) angstrom, b = 16.714(2) angstrom, c = 10.381(4) angstrom, = 107.88(2)-degrees, Z = 4, and R = 0.0 51; 9 is triclinic, space group P1BAR, a = 10.649(l) angstrom, b = 14.122(1) angstrom, c = 10.635(1) angstrom, alpha = 94.64(l)-degrees, beta = 98.04(l)-degrees, gamma = 108.81(l), Z = 2, and R = 0.031; 11 is triclinic, space group P1BAR, a 14.029(1) angstrom, b = 12.355(1) angstrom, c = 8.995(1) angstrom, a = 91.82(l)-degrees, beta = 91.17(l)-degrees, gamma = 91.89(l)-degrees, Z = 2, and R = 0.051