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71.
Jaromír Ková?íkPablo Brañas-Garza Ramón Cobo-ReyesMaría Paz Espinosa Natalia Jiménez Giovanni Ponti 《Physica A》2012,391(3):849-853
We provide empirical evidence to support the claims that social diversity promotes prosocial behavior. We elicit a real-life social network and its members’ adherence to a social norm, namely inequity aversion. The data reveal a positive relationship between subjects’ prosociality and several measures of centrality. This result is in line with the theoretical literature that relates the evolution of social norms to the structure of social interactions and argues that central individuals are crucial for the emergence of prosocial behavior. 相似文献
72.
José Manuel Villalba Franco Dr. Gregor Schnakenburg Prof. Dr. Arturo Espinosa Ferao Prof. Dr. Rainer Streubel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3727-3735
The novel N,P,C‐cage complexes 5 a – f and 6 a – f have been obtained by the reaction of the P‐pentamethylcyclopentadienylphosphinidene complex 2 , generated thermally from 2H‐azaphosphirene complex 1 , with N‐methyl‐C‐arylcarbaldimines 3 a – f . Li/Cl phosphinidenoid complex 8 reacted with 3 a , b to give N,P,C‐cage complexes 6 a , b , whereas with 3 c – f , complexes 6 c – f were obtained in negligible amounts only. Both types of ligand N,P,C‐cage structures 5 and 6 were found to be in an unprecedented equilibrium, with 5 a , f as the predominant species. Transient electrophilic terminal phosphinidene complexes 10 a – f serve as intermediates in both ligand interconversions ( 5 a , f ? 6 a , f ), as evidenced through trapping reactions with phenylacetylene and N‐methyl‐C‐phenylcarbaldimine, thus leading to the novel N,P,C‐cage complexes 13 b and 15 . DFT calculations predicted a small difference in the relative energies of the two types of N,P,C‐cage ligands, and a remarkable stabilisation of the aminophosphinidene complex 10 as the common precursor, thereby providing an insight into this surprising 5‐ring–3‐ring interconversion. In depth analysis of intermediate 10 revealed the occurrence of both through‐bond (conventional inductive/mesomeric effects) and through‐space (non‐covalent interactions) mechanisms, which amount to 67.8 and 14.4 kcal mol?1, respectively, and account for the remarkable stabilisation of this intermediate. 相似文献
73.
74.
75.
Stafford Beer created Team Syntegrity as a methodology for social interaction that predisposes participants towards shared agreement among varied and sometimes conflicting interests, without compromising the legitimate claims and integrity of those interests. This paper outlines the methodology and the underlying philosophy, describing several applications in a variety of countries and contexts, indicating why such an approach causes us to re-think more traditional approaches to group decision processes, and relating Team Syntegrity to other systems approaches. 相似文献
76.
Derivative spectrophotometric methods have been developed for determining oxytetracycline and doxycycline and for resolving their binary mixtures. Oxytetracycline and doxycycline were determined in pharmaceutical samples, urine and honey without any pre-treatment of the samples. In all instances, first-derivative spectra were used. 相似文献
77.
Petr Nesvadba Do Ngoc-Phan Fredy Nydegger Arturo Espinosa Ferao Albert Gossauer 《Helvetica chimica acta》1994,77(7):1837-1850
Following the conventional methodology used for the synthesis of bile pigments, some oxa- and thia-deazabiliverdin analogues were synthetized for the first time. Both UV/VIS spectroscopic and 1H{1H}-NOE difference studies reveal that the oxa-deaza-biliverdin analogue 8a occurs in apolar solvents in a partly ‘stretched’ conformation, whereas the corresponding thia derivative 8b behaves rather like a genuine bile pigment. Unexpectedly, the helical-shaped conformation is also preponderant in a trioxa-trideaza-biliverdin analogue, which could be only characterized in its protonated form 14 . 相似文献
78.
Tárraga A Otón F Espinosa A Desamparados Velasco M Molina P Evans DJ 《Chemical communications (Cambridge, England)》2004,(4):458-459
The synthesis of the first tetraaza[3,3]ferrocenophane, from the previously unreported 1,1'-bis(triphenylphosphoranylidenamino)ferrocene and its conversion into a nitrogen-rich [2,2]bis[3,3]ferrocenophane is described. The electronic behaviour of these multinuclear ferrocenophanes indicates a strong electronic coupling between the iron centers. 相似文献
79.
Elisa M. Castells Martínez Ernesto Carlos González Yileidis Tejeda Amarilys Frómeta Odalys Martín Maryeris Espinosa Lesley del Río Pedro L. Pérez Greilys Morejón Yenitse Perea Antonio Melchor 《Applied biochemistry and biotechnology》2018,186(4):1034-1046
Cystic fibrosis (CF) is a severe autosomal recessive disorder. It is caused by mutations in the CF transmembrane conductance regulator gene. Early diagnosis of CF can be carried out by determining high immunoreactive trypsinogen (IRT) blood values in newborns. A simple sandwich-type ultramicroELISA assay (UMELISA®) has been developed for the measurement of IRT in dried blood spots on filter paper. Strips coated with a high affinity monoclonal antibody directed against IRT are used as solid phase, to ensure the specificity of the assay. The assay is carried out within 20 h. The useful rank of the curve is 0–500 ng/mL, and the lowest detectable concentration is 4.8 ng/mL. Intra- and inter-assay coefficients of variation were lower than 10%. The recovery mean value was 100.3 ± 11.2%. Cross-reactivity with proteins structurally related to IRT (α2-macroglobulin, α1-antitrypsin, and human chymotrypsin) was lower than the detection limit of the assay. Four thousand four hundred six newborn samples from the Cuban Newborn Screening Program were analyzed, and the mean IRT concentration was 12.8 ng/mL. Higher IRT values were obtained when samples were eluted overnight. Regression analysis showed a good correlation with the commercially available AutoDELFIA® Neonatal IRT kit (n?=?3948, r =?0.885, ??=?0.976, p?<?0.01). The analytical performance characteristics of our UMELISA® TIR Neonatal suggest that it can be used for the neonatal screening of CF. 相似文献
80.
García Batlle Marisé Navarrete Tejero Juan Manuel Golzarri José I. Espinosa Guillermo 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):765-774
Journal of Radioanalytical and Nuclear Chemistry - Radioactive contamination factor (RCF) has been proposed as a suitable unit to measure the magnitude of radioactive contamination at global scale,... 相似文献