Polarization switching and nonreciprocity in symmetric and asymmetric magnetophotonic multilayers with nonlinear defect

A one-dimensional magnetophotonic crystal with a nonlinear defect placed either symmetrically or asymmetrically inside the structure is considered. Simultaneous effects of time-reversal nonreciprocity and nonlinear spatial asymmetry in the structure are studied. Bistable response is demonstrated in a such system, accompanied by abrupt polarization switching between two circular or elliptical polarizations for transmitted and reflected waves. The effect is explained in terms of field localization at defect-mode spectral resonances and can be used in the design of thin-film optical isolators and polarization transformation devices.Comment: 20 pages, 8 figure

Myasthenia Gravis Diagnosis with Surface-enhanced Raman Spectroscopy

Modern medicine aims to diagnose diseases at early stages which constitutes a relevant task of biomedical research. The present investigation focuses on myasthenia, a disease that takes the third place in terms of frequency worldwide, has complex symptoms and is difficult to treat. It is early diagnostics that allows for providing competent medical assistance and, sometimes, curing the patient. To detect the cause of the disease, the Raman spectroscopy was used to study blood serum samples covered with quartz glass with gold clusters embedded. The Raman cross-section has been amplified with the gold nanoparticles which made it possible to detect Botulotoxin-A in blood serum of patients suffering from myastheni

Enhancement of absorption bistability by trapping light planar metamaterial

We propose to achieve a strong bistable response of a thin layer of a saturable absorption medium by involving a planar metamaterial specially designed to bear a high-Q trapped-mode resonance in the infrared region.Comment: 11 pages, 4 figure

THE VARIABILITY OF PEANUTS CULTIVARS IN THE NORTH TRANSCASPIAN CONDITION

Analyzed environmental correlations between economically valuable traits of two varieties of peanuts (Arachis hypogaea L.) of different origin - ‘Krasnodarec 14’ and ‘Tashkentskij 32’. The study was conducted in the North of the Astrakhan region on the basis of Prikaspiiskii nauchno-issledovatel'skiiinstitut aridnogo zemledeliya (PNIIAZ) in the North of the Astrakhan area for 6 years. Identified correlations, describing the particular samples. The study showed that the sample from Uzbekistan is better adapted to the conditions of the Astrakhan region

Reproductive inequality in humans and other mammals

To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women’s fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species—including high levels of cooperation among males, high dependence on unequally held rival resources, complementarities between maternal and paternal investment, as well as social and legal institutions that enforce monogamous norms

Learner attention to form in ACCESS task-based interaction

This study explored the potential effects of communicative tasks developed using a reformulation of a task-based language teaching called Automatization in Communicative Contexts of Essential Speech Sequences (ACCESS) that includes automatization of language elements as one of its goals on learner attention to form in task-based interaction. The interaction data collected from a class for English as a second language (ESL) over a four-week period was analysed for incidence, outcome and characteristics (i.e. focus, initiation, response, and turn length) of language-related episodes (LREs) operationalized as evidence of learner attention to form. The results showed that during ACCESS task-based interactions, learners attended to form as reflected in a large number of LREs. Despite being brief, a majority of these LREs were correctly resolved, self-initiated, self- and other-responded, and focused on the target linguistic item: past-tense verbs. These results are discussed in terms of the potential effects of ACCESS task principles, different task features (i.e. task complexity, pre-task modeling, speaker role and group size), and learners’ approach to tasks on the incidence and characteristics of LREs

Women’s subsistence strategies predict fertility across cultures, but context matters

While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities—incorporating market integration—are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies. Societies labeled as “farmers” did not have higher fertility than others, while “foragers” did not have lower fertility. However, at the individual level, we found strong evidence that fertility was positively associated with farming and moderate evidence of a negative relationship between foraging and fertility. Markers of market integration were strongly negatively correlated with fertility. Despite strong cross-cultural evidence, these relationships were not consistent in all populations, highlighting the importance of the socioecological context, which likely influences the diverse mechanisms driving the relationship between fertility and subsistence