Search

The combination of optical and mechanical resonances offers strong hybrid nonlinearities, bistability, and the ability to efficiently control the optical response of nanomechanical photonic metamaterials with electric and magnetic field. While optical resonances can be characterized in routine transmission and reflection experiments, mapping the high‐frequency mechanical resonances of complex metamaterial structures is challenging. Here, it is reported that high‐frequency time‐domain fluctuations in the optical transmission and reflection spectra of nanomechanical photonic metamaterials are directly linked to thermal motion of their components and can give information on the fundamental frequencies and damping of the mechanical modes. This is demonstrated by analyzing time‐resolved fluctuations in the transmission and reflection of dielectric and plasmonic nanomembrane metamaterials at room temperature and low ambient gas pressure. These measurements reveal complex mechanical responses, understanding of which is essential for optimization of such functional photonic materials. At room temperature the magnitude of the observed metamaterial transmission and reflection fluctuations is of order 0.1% but may exceed 1% at optical resonances. [ABSTRACT FROM AUTHOR]

Demonstration of a fiber‐integrated non‐volatile reconfigurable metasurface providing high‐contrast group delay dispersion switching functionality is reported, which may be engineered to operate at wavelengths across the near‐infrared (telecoms) band. Light‐induced amorphous‐crystalline phase switching in a chalcogenide (germanium antimony telluride) metasurface, only a fraction of a wavelength thick, fabricated on the end‐facet of a single‐mode optical fiber, enables intensity and phase modulation of the guided wave at metasurface designated bands. Such devices present a range of opportunities in fiberized remotely programmable phase/intensity multiplexing and dynamic dispersion compensation for emerging telecommunications and data storage/processing applications, including in photonic neural network and neuromorphic computing architectures. [ABSTRACT FROM AUTHOR]

While automation has renewed the debate about labor market policy responses to inequality and job losses, less attention has been given to education policy. We present a general equilibrium model and empirical evidence showing how education mitigates wage inequality resulting from a recent, worst‐case expectation of technology's ability to automate job tasks. Our model predicts that education could reduce automation's marginal effect on the wage gap between lower‐ and higher‐skilled labor by up to 3 percentage points. Education policies that promote automation‐complementing skill formation would reduce the need for costly labor market and wealth redistribution interventions later in life. [ABSTRACT FROM AUTHOR]

One of the most fascinating properties of chiral molecules is their ability to rotate the polarization of light. Since Faraday's experiments in 1845, it has been known that nonreciprocal polarization rotatory power can be induced by a magnetic field. But can reciprocal polarization rotation in chiral molecules be influenced by an electric field? In the 1960s, Aizu and Zheludev introduced the phenomenon of electrogyration. While the linear (Pockels) and quadratic (Kerr) electro‐optical effects describe how an external electric field changes linear birefringence and dichroism, electrogyration describes how a field changes the circular birefringence and dichroism of a medium. Electrogyration is observed in dielectrics, semiconductors, and ferroelectrics, but the effect is small. This work demonstrates a nanostructured photonic metamaterial that exhibits quadratic electrogyration—proportional to the square of the applied electric field—six orders of magnitude stronger than in any natural medium. Giant quadratic electrogyration emerges as electrostatic forces acting against forces of elasticity change the chiral configuration of the metamaterial's nanoscale building blocks and consequently its polarization rotatory power. This observation of giant electrogyration alters the perception of the effect from that of an esoteric phenomenon into a functional part of the electro‐optic toolkit with application potential. [ABSTRACT FROM AUTHOR]

Objective: Synovial membrane inflammation is common in osteoarthritis (OA) and increases cartilage injury. However, synovial fluid and histology studies suggest that OA inflammatory responses are not homogeneous. Greater understanding of these responses may provide new insights into OA disease mechanisms. We undertook this study to develop a novel multiparameter approach to phenotype synovial responses in knee OA. Methods: Cell composition and soluble protein production were measured by flow cytometry and multiplex enzyme‐linked immunosorbent assay in synovium collected from OA patients undergoing knee replacement surgery (n = 35). Results: Testing disaggregation conditions showed that aggressive digestion improved synovial cell yield and mesenchymal staining by flow cytometry, but it negatively impacted CD4+ T cell and CD56+ natural killer cell staining. Less aggressive digestion preserved these markers and showed highly variable T cell infiltration (range 0–43%; n = 32). Correlation analysis identified mesenchymal subpopulations associated with different nonmesenchymal populations, including macrophages and T cells (CD45+CD11b+HLA−DR+ myeloid cells with PDPN+CD73+CD90−CD34− mesenchymal cells [r = 0.65, P < 0.0001]; and CD45+CD3+ T cells with PDPN+CD73+CD90+CD34+ mesenchymal cells [r = 0.50, P = 0.003]). Interleukin‐6 (IL‐6) measured by flow cytometry strongly correlated with IL‐6 released by ex vivo culture of synovial tissue (r = 0.59, P = 0.0012) and was highest in mesenchymal cells coexpressing CD90 and CD34. IL‐6, IL‐8, complement factor D, and IL‐10 release correlated positively with tissue cellularity (P = 0.0042, P = 0.018, P = 0.0012, and P = 0.038, respectively). Additionally, increased CD8+ T cell numbers correlated with retinol binding protein 4 (P = 0.033). Finally, combining flow cytometry and multiplex data identified patient clusters with different types of inflammatory responses. Conclusion: We used a novel approach to analyze OA synovium, identifying patient‐specific inflammatory clusters. Our findings indicate that phenotyping synovial inflammation may provide new insights into OA patient heterogeneity and biomarker development. [ABSTRACT FROM AUTHOR]

Few studies have experimentally manipulated sleep to study its effect on aggressive behavior. The current study examined how reactive aggression was affected by having sleep restricted to 4-hours on a single night, a level of disruption commonly experienced. Both rested and sleep-restricted participants completed the Point Subtraction Aggression Paradigm (PSAP), a laboratory task in which participants seek to earn points, are provoked by a fictitious opponent stealing their points, and may choose to steal points in response. Logistic mixed-effect models were used to investigate the effect of sleep restriction and the role of sex hormones on the odds of choosing to steal. For men, and women in the luteal phase of the menstrual cycle, sleep restriction did not result in significant changes reactive aggression, although the patterns of aggressive behavior appeared less reactive and retaliatory in nature. For women in the follicular phase of the menstrual cycle, sleep restriction was associated with higher levels of reactive aggression. For both men and women in the luteal phase, sleep restriction disrupted an association between hormone change over the task (testosterone and estradiol, respectively) and reactive aggression that was observed in their control participants. In addition, higher testosterone before the PSAP in men was associated with maintaining a high level of stealing over the task. These results indicate a complex dynamic in which sex hormones and sleep interact to predict aggressive behavior in response to provocation. [ABSTRACT FROM AUTHOR]

We explored changes in multiscale brain signal complexity and power‐law scaling exponents of electroencephalogram (EEG) frequency spectra across several distinct global states of consciousness induced in the natural physiological context of the human sleep cycle. We specifically aimed to link EEG complexity to a statistically unified representation of the neural power spectrum. Further, by utilizing surrogate‐based tests of nonlinearity we also examined whether any of the sleep stage‐dependent changes in entropy were separable from the linear stochastic effects contained in the power spectrum. Our results indicate that changes of brain signal entropy throughout the sleep cycle are strongly time‐scale dependent. Slow wave sleep was characterized by reduced entropy at short time scales and increased entropy at long time scales. Temporal signal complexity (at short time scales) and the slope of EEG power spectra appear, to a large extent, to capture a common phenomenon of neuronal noise, putatively reflecting cortical balance between excitation and inhibition. Nonlinear dynamical properties of brain signals accounted for a smaller portion of entropy changes, especially in stage 2 sleep. [ABSTRACT FROM AUTHOR]

Both sleep and future relevance influence memory consolidation; however, limited research has investigated their role in memory reconsolidation. We manipulated the future relevance of both stable and labile memories in need of reconsolidation. Two groups learned two blocks of syllable pairs on one evening and were told they would be tested on one of the blocks later. On the second evening, one group (Labile) received reminders designed to return their memories of syllable pairs to a labile state, while a second group (Stable) received reminders designed to leave these memories in a stable state. No significant differences in memory retention were found between blocks or groups the following morning. Frontal delta (0.5-4 Hz) electroencephalographic power during Stage 2 sleep correlated positively with retention of future-relevant material exclusively in the Labile group. Central theta (4-8 Hz) electroencephalographic power during rapid eye movement ( REM) sleep correlated positively with the extent to which the Labile group selectively retained future-relevant material. These relationships suggest that sleep-dependent processes are involved in an economical reprocessing of memories beyond the initial stages of consolidation. [ABSTRACT FROM AUTHOR]

Animal growth relative to food energy input is of key importance to agricultural production. Several recent studies highlighted genetic markers associated with food conversion efficiency in beef cattle, and there is now a requirement to validate these associations in additional populations and to assess their potential utility for selecting animals with enhanced food-use efficiency. The current analysis tested a population of dairy cattle using 138 DNA markers previously associated with food intake and growth in a whole-genome association analysis of beef animals. Although seven markers showed point-wise significance at P < 0.05, none of the single-nucleotide polymorphisms tested were significantly associated with food conversion efficiency after correction for multiple testing. These data do not support the involvement of this subset of previously implicated markers in the food conversion efficiency of the physiologically distinct New Zealand Holstein- Friesian dairy breed. [ABSTRACT FROM AUTHOR]

1. Effects of sand burial and nutrients on the ability of sand-dune willow ( Salix cordata) to tolerate or resist herbivory by the beetle Altica subplicata were evaluated in field experiments. 2. To assess tolerance, all combinations of sand burial (none, 50%), nutrients (presence, absence), and beetles (presence, absence) were applied to caged plants and growth responses to herbivory were measured. Sand burial increased plant growth rate, but decreased S. cordata's tolerance to herbivory. Although nutrients increased growth, tolerance to herbivory was unaffected. 3. To assess resistance, plants were exposed to all combinations of sand burial and nutrients, and then to natural beetle colonisation. The presence of nutrients, but not sand burial, significantly increased the percentage of plants with beetles, for both adults and larvae. This decreased resistance to beetles of plants grown with added nutrients occurred only in the absence of sand burial. 4. The performance and preference of beetles were examined in laboratory experiments. Larvae developed faster and had increased pupation success on plants with nutrients added. Beetles also showed a marginally significant feeding preference for leaves grown with added nutrients. Thus, S. cordata tolerance to herbivory was affected by sand burial, whereas resistance, preference, and performance were affected by nutrient level. [ABSTRACT FROM AUTHOR]

Seeks to develop an evolutionary perspective on warmth and affection as a developmental construct. How warmth can be conceptualized as a reward system; Why warmth has an important motivational role for children; Contrast with relationships based on exploitation and aggression.

This article interprets the five-factor model as subsuming variation in normative, species-typical systems with adaptive functions in the human environment of evolutionary adaptedness. It is argued that the evolutionary logic of personality systems is apparent in the patterning of mean sex differences in personality. Personality systems are conceptualized as evolved motivational systems with an affective core. The evolved motive dispositions at the core of personality anchor a hierarchy of levels of cognitive and behavioral functioning aimed at attaining or avoiding the affective states central to these personality systems. Personality systems are seen as often in dynamic conflict within individuals and as highly compartmentalized in their functioning between settings. While variation in personality consists of a range of viable strategies for humans, extremes on these systems tend to be maladaptive, although in at least some cases individuals who approach the maladaptive extremes of individual variation may be viewed as engaging in high-risk evolutionary strategies. Within this wide range of viable strategies, personality variation functions as a resource environment for individuals in the sense that personality variation is evaluated according to the interests of the evaluator. [ABSTRACT FROM AUTHOR]

Explores the relationship between parent-child play interaction and peer interactive competence. Ratings of children's competence by their teachers; Association between differential patterns of maternal and paternal behavior and social competence of boys and girls; Association between maternal directiveness and popularity for girls.

In article number 1800395, Behrad Gholipour, Kevin F. MacDonald, and co‐workers show that when an array of subwavelength apertures in a metal film is filled with a chalcogenide semiconductor acting as a low‐epsilon medium at optical frequencies, an increase in transmission is observed over a broad range of plasmonic frequencies, and found to be enabled by "laminar" flow of energy through the chalcogenide inclusions. [ABSTRACT FROM AUTHOR]

When an array of subwavelength apertures in a metal film is filled with a chalcogenide semiconductor acting as a low‐epsilon medium at optical frequencies, an increase in transmission is observed over a broad range of plasmonic frequencies, and found to be enabled by "laminar" flow of energy through the chalcogenide inclusions. As losses decrease in such a low‐epsilon medium, with causality‐bound dispersion of complex relative permittivity, a peak in transmission emerges at a wavelength tending toward that of unitary refractive index, while counterintuitively the absorption of the composite structure increases. "Laminar flow" transmission of light, suppression of plasmonic powerflow vortices, and levels of absorption increasing with decreasing Joule losses can be observed in metamaterials combining plasmonic nanostructures with chalcogenide semiconductor inclusions exhibiting low‐epsilon/low‐index characteristics. [ABSTRACT FROM AUTHOR]

Four out of fifteen burials from the Tylos period ( c.200 BC – AD 200), presented by Toft Jensen in this number of AAE, contained bones of the domestic chicken ( Gallus gallus) and represent the earliest remains of that species found on the island of Bahrain. [ABSTRACT FROM AUTHOR]