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We present millisecond quantitative serial X-ray crystallography at 1.7 Å resolution demonstrating precise optical control of reversible population transfer from Trans-Cis and Cis-Trans photoisomerization of a reversibly switchable fluorescent protein, rsKiiro. Quantitative results from the analysis of electron density differences, extrapolated structure factors, and occupancy refinements are shown to correspond to optical measurements of photoinduced population transfer and have sensitivity to a few percent in concentration differences. Millisecond time-resolved concentration differences are precisely and reversibly controlled through intense continuous wave laser illuminations at 405 and 473 nm for the Trans-to-Cis and Cis-to-Trans reactions, respectively, while the X-ray crystallographic measurement and laser illumination of the metastable Trans chromophore conformation causes partial thermally driven reconversion across a 91.5 kJ/mol thermal barrier from which a temperature jump between 112 and 128 K is extracted.

CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic di-AMP, is a secondary messenger that is essential for the viability of many bacteria. Its absence in humans makes CdaA a very promising and attractive target for the development of new antibiotics. Here, the structural results are presented of a crystallographic fragment screen against CdaA from Listeria monocytogenes, a saprophytic Gram-positive bacterium and an opportunistic food-borne pathogen that can cause listeriosis in humans and animals. Two of the eight fragment molecules reported here were localized in the highly conserved ATP-binding site. These fragments could serve as potential starting points for the development of antibiotics against several CdaA-dependent bacterial species., (open access.)

Proton transport is indispensable for cell life. It is believed that molecular mechanisms of proton movement through different types of proton-conducting molecules have general universal features. However, elucidation of such mechanisms is a challenge. It requires true-atomic-resolution structures of all key proton-conducting states. Here we present a comprehensive function-structure study of a light-driven bacterial inward proton pump, xenorhodopsin, from Bacillus coahuilensis in all major proton-conducting states. The structures reveal that proton translocation is based on proton wires regulated by internal gates. The wires serve as both selectivity filters and translocation pathways for protons. The cumulative results suggest a general concept of proton translocation. We demonstrate the use of serial time-resolved crystallography at a synchrotron source with sub-millisecond resolution for rhodopsin studies, opening the door for principally new applications. The results might also be of interest for optogenetics since xenorhodopsins are the only alternative tools to fire neurons., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

The color red has been implicated in a variety of social processes, including those involving mating. While previous research suggests that women sometimes wear red strategically to increase their attractiveness, the replicability of this literature has been questioned. The current research is a reasonably powered conceptual replication designed to strengthen this literature by testing whether women are more inclined to display the color red 1) during fertile (as compared with less fertile) days of the menstrual cycle, and 2) when expecting to interact with an attractive man (as compared with a less attractive man and with a control condition). Analyses controlled for a number of theoretically relevant covariates (relationship status, age, the current weather). Only the latter hypothesis received mixed support (mainly among women on hormonal birth control), whereas results concerning the former hypothesis did not reach significance. Women (N = 281) displayed more red when expecting to interact with an attractive man; findings did not support the prediction that women would increase their display of red on fertile days of the cycle. Findings thus suggested only mixed replicability for the link between the color red and psychological processes involving romantic attraction. They also illustrate the importance of further investigating the boundary conditions of color effects on everyday social processes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Agthe et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Interleukin-11 (IL-11) is a pleiotropic cytokine with both pro- and anti-inflammatory properties. It activates its target cells via binding to the membrane-bound IL-11 receptor (IL-11R), which then recruits a homodimer of the ubiquitously expressed, signal-transducing receptor gp130. Besides this classic signaling pathway, IL-11 can also bind to soluble forms of the IL-11R (sIL-11R), and IL-11/sIL-11R complexes activate cells via the induction of gp130 homodimerization (trans-signaling). We have previously reported that the metalloprotease ADAM10 cleaves the membrane-bound IL-11R and thereby generates sIL-11R. In this study, we identify the rhomboid intramembrane protease RHBDL2 as a so far unrecognized alternative sheddase that can efficiently trigger IL-11R secretion. We determine the cleavage site used by RHBDL2, which is located in the extracellular part of the receptor in close proximity to the plasma membrane, between Ala-370 and Ser-371. Furthermore, we identify critical amino acid residues within the transmembrane helix that are required for IL-11R proteolysis. We also show that ectopically expressed RHBDL2 is able to cleave the IL-11R within the early secretory pathway and not only at the plasma membrane, indicating that its subcellular localization plays a central role in controlling its activity. Moreover, RHBDL2-derived sIL-11R is biologically active and able to perform IL-11 trans-signaling. Finally, we show that the human mutation IL-11R-A370V does not impede IL-11 classic signaling, but prevents RHBDL2-mediated IL-11R cleavage., (© 2021 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Understanding and controlling defect formation during the assembly of nanoparticles is crucial for fabrication of self-assembled nanostructured materials with predictable properties. Here, time-resolved small-angle X-ray scattering was used to probe the temporal evolution of strain and lattice contraction during evaporation-induced self-assembly of oleate-capped iron oxide nanocubes in a levitating drop. We show that the evolution of the strain and structure of the growing mesocrystals is related to the formation of defects as the solvent evaporated and the assembly process progressed. Superlattice contraction during the mesocrystal growth stage is responsible for the rapidly increasing isotropic strain and the introduction of point defects. The crystal strain, quantified by the Williamson-Hall analysis, became more anisotropic due to the formation of stress-relieving dislocations as the mesocrystal growth was approaching completion. Understanding the formation of the transformation of defects in mesocrystals and superlattices could assist in the development of optimized assembly processes of nanoparticles with multifunctional properties.

We introduce a liquid application method for time-resolved analyses (LAMA), an in situ mixing approach for serial crystallography. Picoliter-sized droplets are shot onto chip-mounted protein crystals, achieving near-full ligand occupancy within theoretical diffusion times. We demonstrate proof-of-principle binding of GlcNac to lysozyme, and resolve glucose binding and subsequent ring opening in a time-resolved study of xylose isomerase.

Based on theories of grounded cognition, we assumed that the experience of social exclusion is grounded in a concept of darkness. Specifically, we hypothesized that social exclusion causes perceptual judgments of darkness and a preference for brightness as a compensatory response. To investigate these hypotheses, we conducted four studies using different manipulations and measurements. In Studies 1a and 1b, excluded participants judged a picturized room as darker and drew more attention to its brightest part than included participants. In Study 2, excluded participants judged a surface as darker and decided for brighter clothing than included participants. In Study 3, excluded participants judged their lab room as darker and expressed a higher preference for brightness than included participants. Providing consistent support for our hypotheses, these findings confirm the idea that the experience of social exclusion is grounded in multiple ways that share a common representational system., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The formation of nematically-ordered cellulose nanofiber (CNF) suspensions with an order parameter f max ≈ 0.8 is studied by polarized optical microscopy, small-angle X-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration. The rheological measurements show a strong entangled network over all the concentration range whereas SAXS measurements indicate that at concentrations >1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are modelled as mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions where the correlation distances decrease with concentration. The use of rapid, upscalable osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel/glass formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.

Assembly of bio-based nano-sized particles into complex architectures and morphologies is an area of fundamental interest and technical importance. We have investigated the assembly of sulfonated cellulose nanocrystals (CNC) dispersed in a shrinking levitating aqueous drop using time-resolved small angle X-ray scattering (SAXS). Analysis of the scaling of the particle separation distance (d) with particle concentration (c) was used to follow the transition of CNC dispersions from an isotropic state at 1-2 vol% to a compressed nematic state at particle concentrations above 30 vol%. Comparison with SAXS measurements on CNC dispersions at near equilibrium conditions shows that evaporation-induced assembly of CNC in large levitating drops is comparable to bulk systems. Colloidal states with d vs. c scalings intermediate between isotropic dispersions and unidirectional compression of the nematic structure could be related to the biphasic region and gelation of CNC. Nanoscale structural information of CNC assembly up to very high particle concentrations can help to fabricate nanocellulose-based materials by evaporative methods.

Premature closure of the sutures that connect the cranial bones during development of the mammalian skull results in a phenotype called craniosynostosis. Recently, several craniosynostosis patients with missense mutations within the gene encoding the interleukin-11 receptor (IL-11R) have been described, but the underlying molecular mechanisms have remained elusive. IL-11 is a cytokine that has a crucial role in bone remodeling and activates cells via binding to the IL-11R. Here, we show that patient mutations prevented maturation of the IL-11R, resulting in endoplasmic reticulum retention and diminished cell surface appearance. Disruption of a conserved tryptophan-arginine zipper within the third domain of the IL-11R was the underlying cause of the defective maturation. IL-11 classic signaling via the membrane-bound receptor, but not IL-11 trans-signaling via the soluble receptor, was the crucial pathway for normal skull development in mice in vivo. Thus, the specific therapeutic inhibition of IL-11 trans-signaling does not interfere with skull development., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)

Self-assembly of nanoparticles into superlattices can be used to create hierarchically structured materials with tailored functions. We have used the surface sensitive quartz crystal microbalance with dissipation monitoring (QCM-D) technique in combination with video microscopy (VM) to obtain time-resolved information on the mass increase and rheological properties of evaporation-induced self-assembly of nanocubes. We have recorded the frequency and dissipation shifts during growth and densification of superlattices formed by self-assembly of oleic acid capped, truncated iron oxide nanocubes and analyzed the time-resolved QCM-D data using a Kelvin-Voigt viscoelastic model. We show that the nanoparticles first assemble into solvent-containing arrays dominated by a viscous response followed by a solvent-releasing step that results in the formation of rigid and well-ordered superlattices. Our findings demonstrate that QCM-D can be successfully used to follow self-assembly and assist in the design of optimized routes to produce well-ordered superlattices., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Workflow interruptions are one of the most commonly experienced stressors at work. This research expands existing literature on workflow interruptions in a diary field study. We apply a within-person approach and investigate detrimental effects of daily workflow interruptions on both daily satisfaction with performance and daily emotional exhaustion. Furthermore, we introduce polychronicity (the trait-like preference of a person to deal with several activities at the same time) as a buffering factor in this relationship. Results of the diary study with knowledge workers over 5 consecutive working days (N = 149, 644 daily observations) showed that on days on which participants experienced a large amount of workflow interruptions, they reported lower levels of satisfaction with their performance and higher levels of emotional exhaustion on that same day. Polychronicity failed to moderate the positive association between interruptions and emotional exhaustion. However, polychronicity significantly moderated the negative association between daily interruptions and daily satisfaction with participants' own performance in a way that for people ranking high on polychronicity this negative association was dissolved. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)

We have followed the structural evolution during evaporation-induced self-assembly of sulfonated cellulose nanocrystal (CNC) in the presence of H + and Li + counterions by small-angle X-ray scattering. Drying of CNC-H dispersions results in ordered films that could not be readily redispersed, while the CNC-Li films were disordered and prone to reswelling and redispersion. The scaling of the separation distance ( d ) between CNC particles and the particle concentration ( c ) shows that the CNC-H dispersions display a unidimensional contraction of the nematic structure ( d ∝ c -1 ) during drying, while the CNC-Li dispersions consolidate isotropically ( d ∝ c -1/3 ), which is characteristic for hydrogels with no preferential orientation. Temporal evolution of the structure factor and complementary dynamic light-scattering measurements show that CNC-Li is more aggregated than CNC-H during evaporation-induced assembly. Insights on the structural evolution during CNC assembly and redispersion can promote development of novel and optimized processing routes of nanocellulose-based materials.

Background/aims: The cytokine interleukin-11 (IL-11) has important pro- and anti-inflammatory functions. It activates its target cells through binding to the IL-11 receptor (IL-11R), and the IL-11/IL-11R complex recruits a homodimer of glycoprotein 130 (gp130). N-linked glycosylation, a post-translational modification where complex oligosaccharides are attached to the side chain of asparagine residues, is often important for stability, folding and biological function of cytokine receptors., Methods: We generated different IL-11R mutants via site-directed mutagenesis and analyzed them in different cell lines via Western blot, flow cytometry, confocal microscopy and proliferation assays., Results: In this study, we identified two functional N-glycosylation sites in the D2 domain of the IL-11R at N127 and N194. While mutation of N127Q only slightly affects cell surface expression of the IL-11R, mutation of N194Q broadly prevents IL-11R appearance at the plasma membrane. Accordingly, IL-11R mutants lacking N194 are retained within the ER, whereas the N127 mutant is transported through the Golgi complex to the cell surface, uncovering a differential role of the two N-glycan sequons for IL-11R maturation. Interestingly, IL-11R mutants devoid of one or both N-glycans are still biologically active. Furthermore, the IL-11RN127Q/N194Q mutant shows no inducible shedding by ADAM10, but is rather constitutively released into the supernatant., Conclusion: Our results show that the two N-glycosylation sites differentially influence stability and proteolytic processing of the IL-11R, but that N-linked glycosylation is not a prerequisite for IL-11 signaling., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

Interleukin-11 (IL-11) and IL-6 are secreted glycoproteins which fulfill important homeostatic functions. Activation of target cells occurs via membrane-bound IL-11 and IL-6 receptors (IL-11R and IL-6R, respectively). Formation of IL-11/IL-11R and IL-6/IL-6R complexes triggers the recruitment of a homodimer of the ubiquitously expressed signal-transducing β-receptor gp130 (classic signaling). IL-11R and IL-6R can be shed by several proteases, albeit with different preferences and specificities, and these soluble receptors (sIL-11R and sIL-6R) act as agonists and can activate in principle all cells via gp130. We have termed these protease-controlled pathways IL-6 and IL-11 trans-signaling. In this review, we describe the basic biology of both cytokines and summarize the current knowledge how proteases control and shape the trans-signaling pathways of the two cytokines. We will further highlight how the underlying molecular mechanisms can be used to design specific inhibitors that block trans, but not classic signaling of IL-11 and IL-6. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The cytokine interleukin (IL)-11 activates its target cells through binding to the membrane-bound IL-11 receptor (IL-11R). Female mice deficient in IL-11R (Il11ra -/- ) are infertile due to a defect in decidualization when the blastocyst implants. We have recently shown that IL-11 can also signal via a soluble IL-11R (trans-signaling). Which IL-11 pathway is required for fertility in mice is unknown. We confirm that female Il11ra -/- mice, lacking both classic and trans-signaling, are infertile. In contrast, the selective blockade of IL-11 trans-signaling does not affect fertility in mice. These results show that classic, but not trans-signaling of IL-11, is essential for fertility in mice., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Muscle dysmorphia (MD) is a relatively young diagnosis referring to the desire for a high degree in lean muscle mass, while simultaneously believing that one is insufficiently muscular, mostly found in men. It goes along with a risk for social withdrawal to maintain rigid exercise and dietary regimen. The aim of the current study was thus, to explore differences in men with and without a risk for muscle dysmorphia regarding their desire for social interaction. Furthermore, we investigated potential effects of individual social comparison tendencies (the tendency to compare oneself with persons who are perceived to be superior or inferior to oneself on a certain dimension) and of one's own body schema on the desire for social interaction., Methods: One hundred physically active, college aged Austrian men were recruited via social media and flyers at fitness centers and the sports department of the University of Vienna. Participants were randomly assigned to a priming condition evoking their own body schema or a control condition and had to state their desire for social interaction with male or female stimulus persons of high or average attractiveness. We conducted a 2 (group of participant; men with vs. without a risk for MD) × 2 (priming condition; priming vs. non-priming) × 2 (attractiveness of stimulus person; highly attractive vs. less attractive) experimental design with different social comparison tendencies as covariates., Results: Men with a risk for muscle dysmorphia showed lesser desire for social interaction than men without this risk, which can be seen as a risk factor for psychopathological outcomes. Generally, men with and without a risk for muscle dysmorphia did not differ with regard to their preferences for attractive stimulus persons as subjects for social interaction. We confirmed the notion that a tendency for downward social comparisons goes along with a diminished desire for social interaction., Conclusions: This study showed that men with a risk for muscle dysmorphia appeared to be at higher risk for social withdrawal and that this is associated with social comparison tendencies. Future investigations on clinical populations are needed, for this population is highly prone to social isolation and negative outcomes related to it.

We have studied the growth of ordered arrays by evaporation-induced self-assembly of iron oxide nanocubes with edge lengths of 6.8 and 10.1 nm using video microscopy (VM) and quartz crystal microbalance with dissipation monitoring (QCM-D). Ex situ electron diffraction of the ordered arrays demonstrates that the crystal axes of the nanocubes are coaligned and confirms that the ordered arrays are mesocrystals. Time-resolved video microscopy shows that growth of the highly ordered arrays at slow solvent evaporation is controlled by particle diffusion and can be described by a simple growth model. The growth of each mesocrystal depends only on the number of nanoparticles within the accessible region irrespective of the relative time of formation. The mass of the dried mesocrystals estimated from the analysis of the bandwidth-shift-to-frequency-shift ratio correlates well with the total mass of the oleate-coated nanoparticles in the deposited dispersion drop.

Signaling of the cytokine interleukin-6 (IL-6) via its soluble IL-6 receptor (sIL-6R) is responsible for the proinflammatory properties of IL-6 and constitutes an attractive therapeutic target, but how the sIL-6R is generated in vivo remains largely unclear. Here, we use liquid chromatography-mass spectrometry to identify an sIL-6R form in human serum that originates from proteolytic cleavage, map its cleavage site between Pro-355 and Val-356, and determine the occupancy of all O- and N-glycosylation sites of the human sIL-6R. The metalloprotease a disintegrin and metalloproteinase 17 (ADAM17) uses this cleavage site in vitro, and mutation of Val-356 is sufficient to completely abrogate IL-6R proteolysis. N- and O-glycosylation were dispensable for signaling of the IL-6R, but proteolysis was orchestrated by an N- and O-glycosylated sequon near the cleavage site and an N-glycan exosite in domain D1. Proteolysis of an IL-6R completely devoid of glycans is significantly impaired. Thus, glycosylation is an important regulator for sIL-6R generation., Competing Interests: The authors have declared that no competing interests exist.

Research corroborates the notion that fundamental social motives play an important role in biases that favor attractive people. Although an adaptationist framework expects favorable social effects of good looks in most situations and contexts, it simultaneously allows for potential negative social reactions and outcomes that may be elicited by physical attractiveness in other contexts. These effects of attractiveness reflect the reproductive opportunities and threats posed by potential mates and rivals.

Mesocrystals composed of crystallographically aligned nanocrystals are present in biominerals and assembled materials which show strongly directional properties of importance for mechanical protection and functional devices. Mesocrystals are commonly formed by complex biomineralization processes and can also be generated by assembly of anisotropic nanocrystals. Here, we follow the evaporation-induced assembly of maghemite nanocubes into mesocrystals in real time in levitating drops. Analysis of time-resolved small-angle X-ray scattering data and ex situ scanning electron microscopy together with interparticle potential calculations show that the substrate-free, particle-mediated crystallization process proceeds in two stages involving the formation and rapid transformation of a dense, structurally disordered phase into ordered mesocrystals. Controlling and tailoring the particle-mediated formation of mesocrystals could be utilized to assemble designed nanoparticles into new materials with unique functions.

The color red has special meaning in mating-relevant contexts. Wearing red can enhance perceptions of women's attractiveness and desirability as a potential romantic partner. Building on recent findings, the present study examined whether women's (N = 74) choice to display the color red is influenced by the attractiveness of an expected opposite-sex interaction partner. Results indicated that female participants who expected to interact with an attractive man displayed red (on clothing, accessories, and/or makeup) more often than a baseline consisting of women in a natural environment with no induced expectation. In contrast, when women expected to interact with an unattractive man, they eschewed red, displaying it less often than in the baseline condition. Findings are discussed with respect to evolutionary and cultural perspectives on mate evaluation and selection.

Interleukin (IL)-11 has been shown to be a crucial factor for intestinal tumorigenesis, lung carcinomas, and asthma. IL-11 is thought to exclusively mediate its biological functions through cell-type-specific expression of the membrane-bound IL-11 receptor (IL-11R). Here, we show that the metalloprotease ADAM10, but not ADAM17, can release the IL-11R ectodomain. Chimeric proteins of the IL-11R and the IL-6 receptor (IL-6R) revealed that a small juxtamembrane portion is responsible for this substrate specificity of ADAM17. Furthermore, we show that the serine proteases neutrophil elastase and proteinase 3 can also cleave the IL-11R. The resulting soluble IL-11R (sIL-11R) is biologically active and binds IL-11 to activate cells. This IL-11 trans-signaling pathway can be inhibited specifically by the anti-inflammatory therapeutic compound sgp130Fc. In conclusion, proteolysis of the IL-11R represents a molecular switch that controls the IL-11 trans-signaling pathway and widens the number of cells that can be activated by IL-11., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

The cytokines interleukin-11 (IL-11) and IL-6 are important proteins with well-defined pro- and anti-inflammatory functions. They activate intracellular signaling cascades through a homodimer of the ubiquitously expressed signal-transducing β-receptor glycoprotein 130 (gp130). Specificity is gained through the cell- and tissue-specific expression of the nonsignaling IL-11 and IL-6 α-receptors (IL-11R and IL-6R), which determine the responsiveness of the cell to these two cytokines. IL-6 is a rare example, where its soluble receptor (sIL-6R) has agonistic properties, so that the IL-6/sIL-6R complex is able to activate cells that are usually not responsive to IL-6 alone (trans-signaling). Recent evidence suggests that IL-11 can signal via a similar trans-signaling mechanism. In this review, we highlight similarities and differences in the functions of IL-11 and IL-6. We summarize current knowledge about the generation of the sIL-6R and sIL-11R by different proteases and discuss possible roles during inflammatory processes. Finally, we focus on the selective and/or combined inhibition of IL-6 and IL-11 signaling and how this might translate into the clinics.

We demonstrate that spatial confinement can be used to control the orientational and translational order of cubic nanoparticles. For this purpose we have combined X-ray scattering and scanning electron microscopy to study the ordering of iron oxide nanocubes that have self-assembled from toluene-based dispersions in nanofluidic channels. An analysis of scattering vector components with directions parallel and perpendicular to the slit walls shows that the confining walls induce a preferential parallel alignment of the nanocube (100) faces. Moreover, slit wall separations that are commensurate with an integer multiple of the edge length of the oleic acid-capped nanocubes result in a more pronounced translational order of the self-assembled arrays compared to incommensurate confinement. These results show that the confined assembly of anisotropic nanocrystals is a promising route to nanoscale devices with tunable anisotropic properties.

The packing of cellulose nanocrystals (CNC) in the anisotropic chiral nematic phase has been investigated over a wide concentration range by small-angle X-ray scattering (SAXS) and laser diffraction. The average separation distance between the CNCs and the average pitch of the chiral nematic phase have been determined over the entire isotropic-anisotropic biphasic region. The average separation distances range from 51 nm, at the onset of the anisotropic phase formation, to 25 nm above 6 vol % (fully liquid crystalline phase) whereas the average pitch varies from ≈15 μm down to ≈2 μm as ϕ increases from 2.5 up to 6.5 vol %. Using the cholesteric order, we determine that the twist angle between neighboring CNCs increases from about 1° up to 4° as ϕ increases from 2.5 up to 6.5 vol %. The dependence of the twisting on the volume fraction was related to the increase in the magnitude of the repulsive interactions between the charged rods as the average separation distance decreases.

Here we demonstrate how monodisperse iron oxide nanocubes and nanospheres with average sizes between 5 and 27 nm can be synthesized by thermal decomposition. The relative importance of the purity of the reactants, the ratio of oleic acid and sodium oleate, the maximum temperature, and the rate of temperature increase, on robust and reproducible size and shape-selective iron oxide nanoparticle synthesis are identified and discussed. The synthesis conditions that generate highly monodisperse iron oxide nanocubes suitable for producing large ordered arrays, or mesocrystals are described in detail.

Being reminded of the inherently finite nature of human existence has been demonstrated to elicit strivings for sexual reproduction and the formation and maintenance of intimate relationships. Recently, it has been proposed that the perception of potential mating partners is influenced by mortality salience. Using functional magnetic resonance imaging, we investigated the neurocognitive processing of attractive opposite-sex faces after priming with death-related words for heterosexual men and women. Significant modulations of behavioral and neural responses were found when participants were requested to decide whether they would like to meet the presented person. Men were more in favor of meeting attractive women after being primed with death-related words compared to a no-prime condition. Increased neural activation could be found under mortality salience in the left anterior insula and the adjacent lateral prefrontal cortex (lPFC) for both men and women. As previously suggested, we believe that the lPFC activation reflects an approach-motivated defense mechanism to overcome concerns that are induced by being reminded of death and dying. Our results provide insight on a neurocognitive level that approach motivation in general, and mating motivation in particular is modulated by mortality salience., (© The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.)

Previous research indicates positive effects of a person's attractiveness on evaluations of opposite-sex persons, but less positive or even negative effects of attractiveness on same-sex evaluations. These biases are consistent with social motives linked to mate search and intrasexual rivalry. In line with the hypothesis that such motives should not become operative until after puberty, 6- to 12-year-old participants (i.e., children) displayed no evidence for biased social evaluations based on other people's attractiveness. In contrast, 13- to 19-year-old participants (i.e., adolescents) displayed positive and negative attractiveness biases toward opposite- and same-sex targets, respectively. Moreover, these biases increased with the age-and thus the reproductive relevance-of the targets being evaluated. Findings corroborate the relevance of mating-related motives for social judgment and illustrate how such biases can grow during human development. At a broader conceptual level, this research demonstrates the utility of investigating proximate social judgment processes through the lens of adaptationist thinking.

According to the recently discovered sexual attribution bias (SAB), young adults attribute the success of same-aged, same-sex attractive stimulus persons in a more derogative way than the success of less attractive same-sex persons, whereas this pattern is reversed for members of the opposite sex. Because this bias has so far only been investigated with respect to attributions in success scenarios, two studies examined its potential transferability to other psychological variables and settings: Study 1 (N = 419) demonstrated analogous biases for emotions and the desire for social interaction, and Study 2 (N = 509) revealed that the SAB can also be extended to failure scenarios.

Female and male participants (in their early 20s) attributed the success of same-aged (Study 1A-1C) male and female stimulus persons of varying attractiveness to ability, effort, luck, and looks. Consistent with the evolutionary prediction that mating motivation and intrasexual competition determine achievement ascriptions, female participants explained the success of attractive women with luck more and with ability less (i.e., in a derogative way) than they explained the success of less attractive female stimulus persons. However, when the stimulus person was male, women attributed his success to ability more and to luck less (i.e., glorifying) when he was attractive than when he was unattractive. Male participants made derogative attributions for attractive male stimulus persons and unattractive female stimulus persons and glorifying ascriptions for unattractive male stimulus persons and attractive female stimulus persons. We label this pattern of findings sexual attribution bias. The bias disappeared when prepuberty stimulus persons were used as targets (Study 2) and reversed for gay men (Study 3)., (((c) 2007 APA, all rights reserved).)