Four thiophene‐ and furan‐containing 3.3meta(heterocyclo)paracyclophanes were designed and synthesized to study the intramolecular interaction between standard heteroaromatic rings and tetra‐H‐ or ...tetra‐F‐substituted benzenes. A complete conformational analysis, carried out by DFT calculations and variable‐temperature NMR techniques, showed that, despite their structural similarity, these adducts have different conformational preferences and undergo different types of isomerizations depending on the nature of the heterocycle. The thiophene‐derived adducts adopted a parallel stacked arrangement of the aromatic systems in the ground‐state conformations. Their isomerization pathways involved a thiophene ring‐flip process passing through an edge‐to‐face arranged transition state in which the heterocycle is perpendicular to the benzene platform and its sulfur atom points toward the center of that ring. The threshold energy barrier to the ring‐flip process was higher by 10 kJ mol−1 in the case of the adduct featuring the perfluorinated benzene. This difference was rationalized by assuming that the ground‐state conformations of the H‐ and F‐substituted compounds have different stability. On the contrary, the furan‐derived adducts were shown by calculations and NMR spectroscopy to adopt, in their ground‐state conformations, a perpendicular edge‐to‐face disposition of the rings with the oxygen atom pointing toward the benzene platform. The adoption of this arrangement was confirmed by X‐ray crystallography. In the case of these compounds, the isomerization process involved distortion of the CH2SCH2 bridges connecting the aromatic systems and the adoption of transition‐state geometries for which the rings were arranged in a parallel‐stacked orientation. Once again a very nice agreement was observed between the predicted and the experimentally determined geometries and pathways. In the case of the furan‐containing compounds, the threshold barriers were found to be much lower in energy that those observed for the thiophene derivatives. Remarkably, they were virtually independent of the presence of fluorine atoms on the platform benzene ring.
A dive into an electron sea! Four thiophene‐ and furan‐containing 3.3meta(heterocyclo)paracyclophanes were designed and synthesized to study the intramolecular interaction between standard heteroaromatic rings and tetra‐H‐ or tetra‐F‐substituted benzenes. The furan‐derived adducts were shown by calculations and NMR spectroscopy to adopt a perpendicular edge‐to‐face disposition of the rings with the oxygen atom pointing toward the benzene platform (see figure).
The enantioselective organocatalytic reduction of trifluoromethyl aryl and alkyl ketoimines afforded the corresponding fluorinated amines with high chemical and stereochemical efficiency. The Lewis ...base catalyzed reaction with trichlorosilane led to chiral products with a trifluoromethyl group directly linked to the newly generated stereocenter typically in >90% yield and up to 98% e.e.
The enantioselective catalytic HSiCl
3
-mediated reduction led to trifluoromethyl aryl and alkyl amines typically in >90% yield and up to 98% e.e.
In paleopathology, biomechanics allows us to investigate traumas in ancient skeletal remains. The aim of our current research is to reconstruct pathomechanics, treatment and gait of an individual ...from a Late Medieval femur with evident bone callus. In particular, to reconstruct the dynamic of the trauma that caused the injury and the adopted therapeutic measures, taking into account medical knowledges of that time.
The femur was recovered during the archaeological investigation in the Sanctuary of Sacro Monte, Varese (Northern Italy). Classical physical anthropological methods and CT scans were used for macroscopic and radiological measurements of the bone. Finally, the reconstruction of the static and dynamic functional outcomes of the lesion were performed by Observation Gait Analysis (OGA) procedure.
The femur shows an important callus at the middle third proximal of the shaft. The antemortem fracture was oblique and caused by a direct trauma probably related to occupational activities. The alignment of the segments in the frontal plane lead us to assume that the fracture was treated and the femur was immobilized with splints. The overlap and the angle of the segments indicate that the subject was not submitted to traction or fracture reduction. Good bone remodeling and consolidation of the fracture suggest that the subject had gradually led to the resumption of load and walking, although with important effects on posture and movement.
The use of the OGA allows us to highlight the subject's kind of gait after healing.
•Biomechanical analysis can be useful in Forensic Anthropology.•No published study on Analysis related to osteoarchaeological sample.•Represents the use of today clinical reasoning to analyze an ancient bone trauma.•Important to add the experience of Osteoarchaeology and Physical Anthropology.
An efficient organocatalytic methodology has been developed to perform the stereoselective addition of 2-carboxythioesters-1,3-dithiane to nitroalkenes. Under mild reaction conditions ...γ-nitro-β-aryl-α-keto esters with up to 92% ee were obtained, realizing a formal catalytic stereoselective conjugate addition of the glyoxylate anion synthon. The reaction products are versatile starting materials for further synthetic transformations; for example, the simultaneous reduction of the nitro group and removal of the dithiane ring was accomplished, allowing the preparation of a GABA
B
receptor agonist baclofen.
Under mild reaction conditions γ-nitro-β-aryl-α-keto esters with up to 92% ee were obtained, realizing a formal catalytic stereoselective conjugate addition of the glyoxylate anion synthon.
Abstract
There is a general belief that pregnancy has a beneficial effect on endometriosis but evidence is scanty. Moreover, some recent warning reports documented progression-growth of ovarian ...endometriomas during pregnancy. To further elucidate this aspect, we set up a prospective cohort study. We recruited 24 women carrying endometriomas at the time of in vitro fertilization who got pregnant. Selected women were contacted about 12-18 months after oocyte retrieval and invited to refer for ultrasound. The primary aim was to evaluate the modifications of endometriotic cysts after pregnancy. Twenty-four women carrying 40 endometriomas accepted to participate. The number of cysts per patient was significantly reduced following pregnancy (p = 0.003). It was unchanged in eight cases (33%), increased in two cases (8%) and reduced in three cases (13%). In the remaining 11 women (46%), no cyst could be detected. A comparison of the size of the endometrioma could be done in 21 cysts; the mean ± SD diameter before and after pregnancy was 20 ± 9 and 18 ± 7 mm, respectively (p = 0.27). In conclusion, pregnancy has a beneficial effect on endometriomas. A consistent proportion of cysts becomes undetectable after delivery. Further studies are warranted to clarify the mechanisms determining the disappearance of these cysts.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Corps et matière Benaglia, Cecilia; Bertina, Arno; Bertrand, Michel ...
Association des lecteurs de Claude Simon,
12/2017
Journal Article
Recenzirano
Odprti dostop
Une conscience historique habite l’œuvre de Claude Simon et, plus généralement, les écrivains du Nouveau Roman. Ainsi Simon déclarait-il en 1989 à Marianne Alphant : « Les choses. Si le surréalisme ...est né de la guerre de 1914, ce qui s’est passé après la dernière guerre est lié à Auschwitz. Il me semble qu’on l’oublie souvent quand on parle du “nouveau roman”. Ce n’est pas pour rien que Nathalie Sarraute a écrit L’Ère du soupçon ; Barthes, Le Degré zéro de l’écriture. Que des artistes comme Tàpies ou Dubuffet sont partis des graffitis, du mur, ou que Louise Nevelson a fait des sculptures à partir de décombres. Toutes les idéologies s’étaient disqualifiées. L’humanisme, c’était fini … : il n’y a plus de recours, essayons de revenir au primordial, à l’élémentaire, à la matière, aux choses. » Cette livraison des Cahiers entend montrer comment l’œuvre de Simon est marquée par ce retour à l’élémentaire. Elle s’ouvre par la reprise d’un texte court de Simon de 1961 (« Sous le kimono ») et d’un entretien long et rare publié en 1977 dans La Nouvelle critique. Le dossier critique se compose de sept études, dont deux articles anciens de critiques anglo-saxons qui ont fait date (dont l’un traduit pour la première fois), tous centrés sur la question du corps et de la matière. On trouve ensuite les rubriques traditionnelles des Cahiers : un bilan de la réception de Simon à l’étranger (le monde anglo-saxon), les paroles d’écrivains lecteurs de Simon (Arno Bertina et Oliver Rohe), les comptes rendus d’ouvrage et l’actualité de l’œuvre.
RESUMO Objetivou-se avaliar as características quantitativas e qualitativas da carcaça e da carne de cordeiros confinados alimentados com torta de girassol. Foram utilizados 28 cordeiros mestiços ...Suffolk, com quatro 4 meses de idade e peso médio de 21,00±0,74 kg, distribuídos em quatro tratamentos: 0% (controle), 10%, 20% e 30% de inclusão de torta de girassol (% MS). O critério adotado para o abate foi escore corporal (3, em escala de 1 a 5). A inclusão da torta de girassol não influenciou as medidas de comprimento e profundidade da carcaça (P>0,05), pH 24 horas (P>0,05), rendimentos dos cortes comerciais (P>0,05), assim como a distribuição de gordura, espessura de gordura subcutânea e grau de marmoreio (P>0,05). Houve efeito linear (P<0,035) e quadrático (P<0,020) sobre a força de cisalhamento do músculo Longissimus dorsi, indicando elevação da FC conforme aumento do nível de inclusão, não ocorrendo o mesmo para os parâmetros de cor L*, a* e b* (P>0,05). Em relação ao tratamento controle, a inclusão de 20% e 30% de torta de girassol influenciou negativamente a área de olho de lombo (12,00 e 11,43 cm2, respectivamente) (P<0,05), peso de carcaça fria (13,19 e 12,58 kg, respectivamente) (P<0,05), e tempo de confinamento (136,85 e 138,39 dias respectivamente) (P<0,05). A inclusão de até 10% de torta de girassol pode ser recomendada para uso em dietas de cordeiros em confinamento, já que permite a produção de carne e carcaças com características quantitativas e qualitativas satisfatórias, sem afetar negativamente as características de desempenho.
RESUMO Objetivou-se avaliar as características quantitativas e qualitativas da carcaça e da carne de cordeiros confinados alimentados com torta de girassol. Foram utilizados 28 cordeiros mestiços ...Suffolk, com quatro 4 meses de idade e peso médio de 21,00±0,74 kg, distribuídos em quatro tratamentos: 0% (controle), 10%, 20% e 30% de inclusão de torta de girassol (% MS). O critério adotado para o abate foi escore corporal (3, em escala de 1 a 5). A inclusão da torta de girassol não influenciou as medidas de comprimento e profundidade da carcaça (P>0,05), pH 24 horas (P>0,05), rendimentos dos cortes comerciais (P>0,05), assim como a distribuição de gordura, espessura de gordura subcutânea e grau de marmoreio (P>0,05). Houve efeito linear (P<0,035) e quadrático (P<0,020) sobre a força de cisalhamento do músculo Longissimus dorsi, indicando elevação da FC conforme aumento do nível de inclusão, não ocorrendo o mesmo para os parâmetros de cor L*, a* e b* (P>0,05). Em relação ao tratamento controle, a inclusão de 20% e 30% de torta de girassol influenciou negativamente a área de olho de lombo (12,00 e 11,43 cm2, respectivamente) (P<0,05), peso de carcaça fria (13,19 e 12,58 kg, respectivamente) (P<0,05), e tempo de confinamento (136,85 e 138,39 dias respectivamente) (P<0,05). A inclusão de até 10% de torta de girassol pode ser recomendada para uso em dietas de cordeiros em confinamento, já que permite a produção de carne e carcaças com características quantitativas e qualitativas satisfatórias, sem afetar negativamente as características de desempenho.
SUMMARY This study aimed to evaluate the quantitative and qualitative characteristics of carcass and meat of lambs fed sunflower cake. Were used 28 Suffolk crossbred lambs, with 4 months of age and average weight of 21.00 ± 0.74 kg, divided into four treatments: 0% (control), 10%, 20% and 30% of sunflower cake inclusion (% DM). The criteria adopted for the slaughter was body condition score (3, on scale of 1 to 5). The inclusion of sunflower cake did not influence the measurement of length and carcass depth (P>0.05), pH 24 hours (P>0.05), yields of commercial cuts (P>0.05), as well as fat distribution, fat thickness and marbling (P>0.05). There was a linear effect (P <0.035) and quadratic (P <0.020) on the shear force of the Longissimus dorsi muscle, indicating increase in SF as increase the level of inclusion, was not the case for color parameters L *, a * and b * (P>0.05). In relation to the control treatment, the inclusion of 20% and 30% of sunflower cake influenced negatively the ribeye area (12.00 and 11.43 cm2, respectively) (P<0.05), cold carcass weight (13.19 and 12.58 kg, respectively) (P<0.05), and confinement time (136.85 and 138.39 days, respectively) (P<0.05). The inclusion of 10% of sunflower cake can be recommended for use in diets of feedlot lambs, since it allows the production of meat and carcasses with quantitative and qualitative characteristics satisfactory, without adversely affecting the performance characteristics.
PDF
