The Exploitation of Versatile Building Blocks for the Self-Assembly of Novel Molecular Magnets

Using molecular building blocks to self-assemble lattices supporting long-range magnetic order is currently an active area of solid-state chemistry. Consequently, it is the realm of supramolecular chemistry that synthetic chemists are turning to in order to develop techniques for the synthesis of structurally well-defined supramolecular materials. In recent years we have investigated the versatility and usefulness of two classes of molecular building blocks, namely, tris-oxalato transition-metal (M. Pilkington and S. Decurtins, in “Magnetoscience—From Molecules to Materials,” Wiley–VCH, 2000), and octacyanometalate complexes (Pilkington and Decurtins, Chimia 54, 593 (2001)), for applications in the field of molecule-based magnets. Anionic, tris-chelated oxalato building blocks are able to build up two-dimensional honeycomb-layered structural motifs as well as three-dimensional decagon frameworks. The discrimination between the crystallization of the two- or three-dimensional structures relies on the choice of the templating counterions (Decurtins, Chimia 52, 539 (1998); Decurtins et al. Mol. Cryst. Liq. Cryst. 273, 167 (1995); New J. Chem. 117 (1998)). These structural types display a range of ferro, ferri, and antiferromagnetic properties (Pilkington and Decurtins, in “Magnetoscience—From Molecules to Materials”). Octacyanometalate building blocks self-assemble to afford two new classes of cyano-bridged compounds namely, molecular clusters and extended three dimensional networks (J. Larionova et al., Angew. Chem. Int. Ed. 39, 1605 (2000); Pilkington et al., in preparation). The molecular cluster with a MnII9MoV6 core has the highest ground state spin value, S=51/2, reported to-date (Larionova et al., Angew. Chem. Int. Ed. 39, 1605 (2000)). In the high-temperature regime, the magnetic properties are characterized by ferromagnetic intracluster coupling. In the magnetic range below 44 K, the magnetic cluster signature is lost as possibly a bulk behavior starts to emerge. The three-dimensional networks exhibit both paramagnetic and ferromagnetic behavior, since the magnetic properties of these materials directly reflect the electronic configuration of the metal ion incorporated into the octacyanometalate building blocks (Pilkington et al., in preparation). For both the oxalate- and cyanide-bridged materials, we are able to manipulate the magnetic properties of the supramolecular assemblies by tuning the electronic configurations of the metal ions incorporated into the appropriate molecular building blocks (Pilkington and Decurtins, in “Magnetoscience—From Molecules to Materials,” Chimia 54, 593 (2000)).

Capital interplays and the self-rated health of young men: results from a cross-sectional study in Switzerland.

INTRODUCTION We apply capital interplay theory to health inequalities in Switzerland by investigating the interconnected effects of parental cultural, economic and social capitals and personal educational stream on the self-rated health of young Swiss men who live with their parents. METHODS We apply logistic regression modelling to self-rated health in original cross-sectional survey data collected during mandatory conscription of Swiss male citizens in 2010 and 2011 (n = 23,975). RESULTS In comparison with sons whose parents completed mandatory schooling only, sons with parents who completed technical college or university were significantly more likely to report very good or excellent self-rated health. Parental economic capital was an important mediating factor in this regard. Number of books in the home (parental cultural capital), family economic circumstances (parental economic capital) and parental ties to influential people (parental social capital) were also independently associated with the self-rated health of the sons. Although sons in the highest educational stream tended to report better health than those in the lowest, we found little evidence for a health-producing intergenerational transmission of capitals via the education stream of the sons. Finally, the positive association between personal education and self-rated health was stronger among sons with relatively poorly educated parents and stronger among sons with parents who were relatively low in social capital. CONCLUSIONS Our study provides empirical support for the role of capital interplays, social processes in which capitals interpenetrate or co-constitute one another, in the intergenerational production of the health of young men in Switzerland.

Rumination mediates the prospective effect of low self-esteem on depression: A five-wave longitudinal study

Previous research supports the vulnerability model of low self-esteem and depression, which states that low self-esteem operates as a prospective risk factor for depression. However, it is unclear which processes mediate the effect of low self-esteem. To test for the mediating effect of rumination, the authors used longitudinal mediation models, which included exclusively prospective effects and controlled for autoregressive effects of the constructs. Data came from 663 individuals (aged 16 to 62 years), who were assessed 5 times over an 8-month period. The results indicated that low self-esteem predicted subsequent rumination, which in turn predicted subsequent depression, and that rumination partially mediated the prospective effect of low self-esteem on depression. These findings held for both men and women, and for both affective-cognitive and somatic symptoms of depression. Future studies should test for the mediating effects of additional intrapersonal and interpersonal processes.

How quota-based procedures affect the self-ascribed fit and motivation of European women and men striving for leadership positions

The consequences of quota-based hiring policies on women’s and men’s self-ascribed fit and motivation to apply for leadership positions were investigated in the European context. 389 management students (195 women, 194 men) from Switzerland, Germany, and Austria received job advertisements varying in their gender policies. Interestingly, women’s and men’s self-ascribed fit and motivation to apply did not differ when no policy was included. Instead, participant’s agency was the relevant predictor leading to higher perceived fit, resulting in higher inclination to apply. When women were either explicitly invited to apply or preferentially treated when equally qualified, they reported higher fit and inclination to apply compared to both the control condition and men. In contrast, when a quota of 40% women should be established, neither women’s fit nor motivation to apply were increased beyond the levels of the control or men’s. Men were not affected by the different policies.

Hierarchical self-assembly of the DNA-grafted supramolecular polymers

Conjugation of functional entities with a specific set of optical, mechanical or biological properties to DNA strands allows engineering of sophisticated DNA-containing architectures. Among various hybrid systems, DNA-grafted polymers occupy an important place in modern materials science. In this contribution we present the non-covalent synthesis and properties of DNA-grafted linear supramolecular polymers (SPs), which are assembled in a controllable manner from short chimeric DNA-pyrene oligomers. The synthetic oligomers consist of two parts: a 10 nucleotides long DNA chain and a covalently attached segment of variable number of phosphodiester-linked pyrenes. The temperature-dependent formation of DNA-grafted SPs is described by a nucleation-elongation mechanism. The high tendency of pyrenes to aggregate in water, leads to the rapid formation of SPs. The core of the assemblies consists of stacked pyrenes. They form a 1D platform, to which the DNA chains are attached. Combined spectroscopic and microscopic studies reveal that the major driving forces of the polymerization are π-stacking of pyrenes and hydrophobic interactions, and DNA pairing contributes to a lesser extent. AFM and TEM experiments demonstrate that the 1D SPs appear as elongated ribbons with a length of several hundred nanometers. They exhibit an apparent helical structure with a pitch-to-pitch distance of 50±15 nm. Since DNA pairing is a highly selective process, the ongoing studies are aimed to utilize DNA-grafted SPs for the programmable arrangement of functional entities. For example, the addition of non-modified complementary DNA strands to the DNA-grafted SPs leads to the cooperative formation of higher-order assemblies. Also, our experiments suggest that the fluorescent pyrene core of 1D ribbons serves as an efficient donor platform for energy transfer applications.

Hierarchical self-assembly of the DNA-grafted supramolecular polymers

Conjugation of functional entities with a specific set of optical, mechanical or biological properties to DNA strands allows engineering of sophisticated DNA-containing architectures. Among various hybrid systems, DNA-grafted polymers occupy an important place in modern materials science. In this contribution we present the non-covalent synthesis and properties of DNA-grafted linear supramolecular polymers (SPs), which are assembled in a controllable manner from short chimeric DNA-pyrene oligomers. The synthetic oligomers consist of two parts: a 10 nucleotides long DNA chain and a covalently attached segment of variable number of phosphodiester-linked pyrenes. The temperature-dependent formation of DNA-grafted SPs is described by a nucleation-elongation mechanism. The high tendency of pyrenes to aggregate in water, leads to the rapid formation of SPs. The core of the assemblies consists of stacked pyrenes. They form a 1D platform, to which the DNA chains are attached. Combined spectroscopic and microscopic studies reveal that the major driving forces of the polymerization are π-stacking of pyrenes and hydrophobic interactions, and DNA pairing contributes to a lesser extent. AFM and TEM experiments demonstrate that the 1D SPs appear as elongated ribbons with a length of several hundred nanometers. They exhibit an apparent helical structure with a pitch-to-pitch distance of 50±15 nm. Since DNA pairing is a highly selective process, the ongoing studies are aimed to utilize DNA-grafted SPs for the programmable arrangement of functional entities. For example, the addition of non-modified complementary DNA strands to the DNA-grafted SPs leads to the cooperative formation of higher-order assemblies. Also, our experiments suggest that the fluorescent pyrene core of 1D ribbons serves as an efficient donor platform for energy transfer applications.

Refining the vulnerability model of low self-esteem and depression: Disentangling the effects of genuine self-esteem and narcissism

A growing body of research supports the vulnerability model of low self-esteem and depression, which states that low self-esteem is a risk factor for depression. The goal of the present research was to refine the vulnerability model, by testing whether the self-esteem effect is truly due to a lack of genuine self-esteem or due to a lack of narcissistic self-enhancement. For the analyses, we used data from 6 longitudinal studies consisting of 2,717 individuals. In each study, we tested the prospective effects of self-esteem and narcissism on depression both separately for each construct and mutually controlling the constructs for each other (i.e., a strategy that informs about effects of genuine self-esteem and pure narcissism), and then meta-analytically aggregated the findings. The results indicated that the effect of low self-esteem holds when narcissism is controlled for (uncontrolled effect = -.26, controlled effect = -.27). In contrast, the effect of narcissism was close to zero when self-esteem was controlled for (uncontrolled effect = -.06, controlled effect = .01). Moreover, the analyses suggested that the self-esteem effect is linear across the continuum from low to high self-esteem (i.e., the effect was not weaker at very high levels of self-esteem). Finally, self-esteem and narcissism did not interact in their effect on depression; that is, individuals with high self-esteem have a lower risk for developing depression, regardless of whether or not they are narcissistic. The findings have significant theoretical implications because they strengthen the vulnerability model of low self-esteem and depression.

Denying the foreseeability of an event as a means of self-protection. The Impact of Self-Threatening Outcome Information on the Strength of the Hindsight Bias

The hindsight bias represents the tendency of people to falsely believe that they would have predicted the outcome of an event, once the outcome is known. Two experiments will be presented that show a reduction or even reversal of the hindsight bias when the outcome information is self-threatening for the participants. Participants read a report of an interaction between a man and a woman that ended with different outcomes: The woman was raped vs. the woman was not raped vs. no outcome information was given. Results of the first experiment indicated that especially female participants, who did not accept rape myths, showed a reversed hindsight bias, when they received the rape outcome information. The more threatening the rape outcome had been, the lower was their estimated likelihood of rape. Results of the second experiment confirmed those of the first. Female participants, who did not accept rape myths and perceived themselves highly similar to the victim, showed a strong reversed hindsight bias, when threatened by the rape outcome, whereas female participants, who did believe in rape myth and were not similar to the victim, showed a classical hindsight bias. These effects were interpreted in terms of self-serving or in-group serving functions of the hindsight bias: Participants deny the foreseeability of a self-threatening outcome as a means of self-protection even if they are not personally affected by the negative information, but a member of their group.

Partial lateralization of the nasopalatine nerve at the incisive foramen for ridge augmentation in the anterior maxilla prior to placement of dental implants: a retrospective case series evaluating self-reported data and neurosensory testing

The objective of this study was to assess implant therapy after a staged guided bone regeneration procedure in the anterior maxilla by lateralization of the nasopalatine nerve and vessel bundle. Neurosensory function following augmentative procedures and implant placement, assessed using a standardized questionnaire and clinical examination, were the primary outcome variables measured. This retrospective study included patients with a bone defect in the anterior maxilla in need of horizontal and/or vertical ridge augmentation prior to dental implant placement. The surgical sites were allowed to heal for at least 6 months before placement of dental implants. All patients received fixed implant-supported restorations and entered into a tightly scheduled maintenance program. In addition to the maintenance program, patients were recalled for a clinical examination and to fill out a questionnaire to assess any changes in the neurosensory function of the nasopalatine nerve at least 6 months after function. Twenty patients were included in the study from February 2001 to December 2010. They received a total of 51 implants after augmentation of the alveolar crest and lateralization of the nasopalatine nerve. The follow-up examination for questionnaire and neurosensory assessment was scheduled after a mean period of 4.18 years of function. None of the patients examined reported any pain, they did not have less or an altered sensation, and they did not experience a "foreign body" feeling in the area of surgery. Overall, 6 patients out of 20 (30%) showed palatal sensibility alterations of the soft tissues in the region of the maxillary canines and incisors resulting in a risk for a neurosensory change of 0.45 mucosal teeth regions per patient after ridge augmentation with lateralization of the nasopalatine nerve. Regeneration of bone defects in the anterior maxilla by horizontal and/or vertical ridge augmentation and lateralization of the nasopalatine nerve prior to dental implant placement is a predictable surgical technique. Whether or not there were clinically measurable impairments of neurosensory function, the patients did not report them or were not bothered by them.