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• The most important approach for atomic interferometry is the atom chip technology. • Atom chip integrates elements for cooling, trapping and atom manipulation. • Single-layer atom chip is simplified the operation with the atomic ensemble. • Increased heat dissipation from the chip is essential for continuous operation. • Material, geometry and heat sink optimization gives the appropriate temperature. • Continuous cooling of atoms near the chip is a key for future atom optics elements. A single-layer atom chip for laser cooling and trapping of atoms which operates in a continuous regime is designed and experimentally investigated. The continuous regime was achieved by optimizing the processes of heat released and heat removal from the working area of the atom chip. To do this, we use silver microwires and optimization of the heat dissipation through different heat removal channels. The main channels for heat dissipation are the contacts of the silicon substrate of the atom chip with a copper massive base and the heat sink through the clamps. The design of the atom chip ensures efficient heat transfer from the work area to the periphery through the metal layer of the atom chip. Using continuous operation regime, we cooled and trapped about 3 ∙ 105 atoms near the atom chip. [ABSTRACT FROM AUTHOR]

We have suggested and realized a giant asymmetry of the transmission of light propagating through a linear nonmagnetic optical system that consists of a nanohole in metal film deposited on the surface of a one-dimensional photonic crystal. The asymmetry of the light transmission is caused by two factors: (i) practical impossibility to reverse the wavefront of light passing through a nanohole whose diameter is much smaller than the wavelength of light; and (ii) increase of photonic crystal transmission at photonic bandgap wavelengths due to strong modification of k-vector of incident light caused by diffraction on a nanohole (optical 'clearance' of the photonic crystal). We show that in such optical element it is possible to realize optical diode whose reverse transmission can be suppressed by a factor of more than 30 000. Graphical abstract: [ABSTRACT FROM AUTHOR]

A geoarchaeological study of the large Essentuksky 1 kurgan in the Stavropol region of Russia analyzed the chemical composition and micromorphological features of the kurgan's earthen materials and established their relationships with buried soils in the context of previously conducted paleoclimatic reconstructions. The kurgan was 5.5–6.0 m high and more than 60 m in diameter, and consisted of four earthen and three stone constructions. It was built in the second quarter of the 4th millennium BC (the Early Maykop culture) using a precise plan and utilizing the building skills and technologies available at that time. The earthen constructions consisted of alternating layers of dark‐colored slightly compacted humified and pale‐colored dense carbonate‐rich materials, which, in the moist state, were rammed down by ancient builders. These materials were sourced mainly from local soils and contained admixtures of river silt and, at the final stage of building, dung. The physicochemical properties of the earthen constructions as well as the paleosols buried under them are indicative of a short‐term aridization of the climate within the period of building. A gleyed earth with strong iron staining at the kurgan's base and mortar that held the stone constructions was produced by thoroughly mixing and compacting in a wet state, indicating that they were special construction materials. This kurgan is an example of the ancient earth architecture in the steppe zone of Russia over 5500 years ago. [ABSTRACT FROM AUTHOR]

The flanks of the Caucasus Mountains and the steppe landscape to their north offered highly productive grasslands for Bronze Age herders and their flocks of sheep, goat, and cattle. While the archaeological evidence points to a largely pastoral lifestyle, knowledge regarding the general composition of human diets and their variation across landscapes and during the different phases of the Bronze Age is still restricted. Human and animal skeletal remains from the burial mounds that dominate the archaeological landscape and their stable isotope compositions are major sources of dietary information. Here, we present stable carbon and nitrogen isotope data of bone collagen of 105 human and 50 animal individuals from the 5th millennium BC to the Sarmatian period, with a strong focus on the Bronze Age and its cultural units including Maykop, Yamnaya, Novotitorovskaya, North Caucasian, Catacomb, post-Catacomb and late Bronze Age groups. The samples comprise all inhumations with sufficient bone preservation from five burial mound sites and a flat grave cemetery as well as subsamples from three further sites. They represent the Caucasus Mountains in the south, the piedmont zone and Kuban steppe with humid steppe and forest vegetation to its north, and more arid regions in the Caspian steppe. The stable isotope compositions of the bone collagen of humans and animals varied across the study area and reflect regional diversity in environmental conditions and diets. The data agree with meat, milk, and/or dairy products from domesticated herbivores, especially from sheep and goats having contributed substantially to human diets, as it is common for a largely pastoral economy. This observation is also in correspondence with the faunal remains observed in the graves and offerings of animals in the mound shells. In addition, foodstuffs with elevated carbon and nitrogen isotope values, such as meat of unweaned animals, fish, or plants, also contributed to human diets, especially among communities living in the more arid landscapes. The regional distinction of the animal and human data with few outliers points to mobility radii that were largely concentrated within the environmental zones in which the respective sites are located. In general, dietary variation among the cultural entities as well as regarding age, sex and archaeologically indicated social status is only weakly reflected. There is, however, some indication for a dietary shift during the Early Bronze Age Maykop period. [ABSTRACT FROM AUTHOR]

We have realized a plasmonic interferometer formed by a nanoslit and a nanogroove in a single-crystal gold film. The possibility of measuring laser pulses of ultimately short durations, corresponding to two periods of a light wave (6 fs pulse duration), has been demonstrated using this interferometer. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives It is a big challenge to diagnose the motives behind trepanations in prehistoric crania. Surgical-therapeutic attempts may be apparent by the presence of fractures, however, ritual or nonmedical motives are rarely supported by visible evidence in the bones. This article presents data on the trepanations of several individuals from South Russia dating to the Eneolitic and Bronze Age that may indicate a ritual procedure. In these crania an operation was performed in the identical location, the midline, furthermore in one of the most dangerous places, on the obelion. No evidence for traumatic or other pathological reasons for performing the operations was observable. Material and Methods Investigations of two nearby areas of South Russia revealed 13 individuals showing complete perforations in the midline of the cranium. Another one, displaying a depression in the same place, primarily diagnosed as an incomplete trepanation, is discussed considering all differential diagnoses. The trepanations were investigated macroscopically, by plain radiography and computed tomography. The lesions were described in detail, including data on technique, position, size, shape, state of healing, and complications. Results Males and females received the operation between the age of 10 years and mature/senile age. Only grooving and scraping techniques were used and their application differed between sexes. The majority of the patients survived the intervention for a long time. Discussion The region of Southern Russia seems to be a center for special trepanations performed by skilled surgeons, the specific position of the perforations implying more a ritual than therapeutic reason for trepanning. Am J Phys Anthropol 160:665-682, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]