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Pink salmon, the most abundant Pacific salmon, have an obligate 2-year life cycle that leads to reproductively isolated even- and odd-year lineages. Using new and existing data, we examined the genetic structure of both lineages across their distributional range by genotyping 16 681 single-nucleotide polymorphisms for 383 individuals originating from seven pairs of even- and odd-year populations. Distinct differences in standing pools of genetic variation were identified between the lineages; we observed higher levels of heterozygosity, allelic richness, and significantly more private alleles in the odd-year lineage. However, the patterns of population structure were concordant between lineages: the Asian and northern Alaska populations displayed little differentiation but differed significantly from populations in southcentral Alaska and the Pacific Northwest. Our population structure results, in the context of known paleoecological information, suggest that both lineages occupied a northern Beringial refugium as well as a Cascadian refugium in North America during the Last Glacial Maximum. These results highlight the influence of historical patterns of habitat availability on contemporary population structure and support the hypothesis of a pre-glacial origin of the lineages. Le saumon rose, le plus abondant des saumons du Pacifique, a un cycle biologique fixe de deux ans qui se traduit par des lignees d'annees paires et impaires isolees les unes des autres du point de vue de la reproduction. En utilisant des donnees nouvelles et existantes, nous avons examine la structure genetique des deux lignees a la grandeur de leur aire de repartition en genotypant 16 681 polymorphismes mononucleotidiques pour 383 individus issus de sept paires de populations d'annees paires et impaires. Des differences claires dans les bassins de variation genetique existants ont ete cernees entre les lignees; nous avons observe des degres plus eleves d'heterozygotie et de richesse allelique et significativement plus d'alleles particuliers dans la lignee d'annees impaires. Les motifs de structure des populations concordent toutefois entre les deux lignees; les populations asiatiques et du nord de l'Alaska presentent peu de differenciation, mais sont significativement differentes des populations du centre-sud de l'Alaska et du Pacific Northwest. Nos resultats sur la structure des populations, dans le contexte d'information paleoecologique connue, donnent a penser que les deux lignees ont occupe un refuge beringien septentrional ainsi qu'un refuge cascadien en Amerique du Nord durant le dernier maximum glaciaire. Ces resultats soulignent l'influence de motifs de disponibilite d'habitat passes sur la structure actuelle des populations et appuient l'hypothese d'une origine preglaciaire des lignees. [Traduit par la Redaction], Introduction An enduring goal in evolutionary biology is to describe the dynamics that result in population structure, species distribution, and genetic diversity. Groups of organisms that use the same habitat [...]

Many constructions built by ancient civilization hold many mysteries and attract the attention of historians, archaeologists and tourists from all over the world. The most famous and enigmatical among them is the Great (Khufu's-Cheops') Pyramid on the Giza plateau in Egypt. The assignment, construction methods and especially the inside structure of the Pyramid have been the cause of heated debate among historians and researchers since ancient times. Unfortunately, not only researchers are interested in ancient structures and excavation sites of archaeological values, but also robbers and illegal seekers of archaeological values. This led to the partial destruction of the Pyramid by the order of the Arab caliph Al-Ma'mun in the 9th century AD. From the middle of the last century, the point of view has prevailed that only non-destructive testing methods are acceptable when examining ancient structures. In the 1960s, a technology was proposed for transilluminating the pyramids of Giza by muons, which are generated by cosmic rays in the Earth's atmosphere. This method gave promising results. Other means were also proposed, which include radar, as well as gravitational and vibration technologies. However, despite numerous attempts to use them, no significant success or discovery has been achieved. A discussion of these methods, their applications and partial successes is the subject of this article. [ABSTRACT FROM AUTHOR]

The study, preservation and restoration of the cultural heritage objects of mankind are not only of great cultural importance but also have a significant economic component because cultural values of past centuries attract tourists from all over the world. The use of modern technical and scientific achievements in the field of non-destructive testing makes it possible to obtain new knowledge about cultural objects regarding their origin and dating, as well as to contribute to their better restoration and preservation. An important component of their use is additional opportunities to identify high quality fakes of original cultural objects that have historical significance. The capabilities of various non-destructive testing (NDT) methods used to examine cultural objects are characterized by their penetration depth, resolution, and sensitivity to material properties. Thus, in many cases, it is necessary to perform multi-sensor non-destructive testing and creating large data sets that require an efficient evaluation. This article considers an example of using microwave (MW) holographic sensors for the examining of an old Orthodox Russian Icon dated of the late 19th century. The paper describes the technology of microwave holography, which has recently been applied to the examination of art works. Unlike the well-studied X-ray method, MW holography makes it possible to examine objects with one-sided access. Its other advantages are the relative cheapness of the equipment and the safety of use due to the low level of radiation. The article describes a MW holograms reconstruction algorithm, as well as a method for improving the quality of obtained MW images. The data collected at MW research of the Icon are compared with the results of X-ray examination and confirmed by subsequent opening and visual examination performed by professional restorers. [ABSTRACT FROM AUTHOR]

We genotyped Chinook salmon (Oncorhynchus tshawytscha) from the Bering Sea and North Pacific Ocean for 43 single-nucleotide polymorphisms (SNPs) to investigate seasonal distribution and migration patterns. We analyzed 3563 immature fish from 22 spatiotemporal strata; composition analyses were performed using genotype data from spawning stocks spanning the species range. Substantial variation in stock composition existed among spatial and seasonal strata. We inferred patterns of seasonal migration based upon these data along with data from previous tag, scale, and parasite studies. We found that stocks from western Alaska and Yukon River overwinter on the Alaska continental shelf then travel to the middle and western Bering Sea during spring-fall. Stocks from California to Southeast Alaska were distributed in Gulf of Alaska year-round, with a substantial portion of this group migrating northward to the eastern Bering Sea during spring-fall. Proportions of Russian stocks increase when moving east to west in both the Bering Sea and North Pacific Ocean. These data can be used to better understand the impacts of fisheries and climate change on this valuable resource. Nous avons realise le genotypage de saumons quinnat (Oncorhynchus tshawytscha) de la mer de Bering et du Pacifique Nord pour 43 sites de polymorphisme mononucleotidique (SNPs) afin d'etudier la repartition saisonniere et les habitudes migratoires de ces saumons. Nous avons analyse 3563 poisons immatures issus de 22 strates spatiotemporelles; des analyses de la composition ont ete realisees a partir de donnees de genotypage pour des stocks reproducteurs recoupant toute l'aire de repartition de l'espece. Des variations importantes sur le plan de la composition des stocks des differentes strates spatiales et saisonnieres ont ete observees. Nous avons infere les habitudes de migration saisonnieres a la lumiere de ces donnees, ainsi que de donnees issues d'etudes de marquage, a l'echelle et de parasites. Nous avons constate que les stocks de l'ouest de l'Alaska et du fleuve Yukon passent l'hiver sur la plate-forme continentale de l'Alaska pour ensuite se diriger vers le milieu et l'ouest de la mer de Bering du printemps a l'automne. Des stocks provenant de la Californie au sud-est de l'Alaska sont presents dans le golfe d'Alaska a l'annee longue, une portion importante de ce groupe migrant vers le nord jusque dans la partie orientale de la mer de Bering, du printemps a l'automne. La proportion de stocks russes augmente d'est en ouest dans la mer de Bering et le Pacifique Nord. Ces donnees peuvent servir a etablir une meilleure comprehension des impacts de la peche et des changements climatiques sur cette ressource de grande valeur. [Traduit par la Redaction], Introduction Knowledge of the dynamics of migration and harvest of marine organisms is necessary to enable adequate conservation and management (Ruggerone and Goetz 2004; Welch et al. 2011). This critical [...]

Molecular electronic sensors of motion parameters use miniature electrochemical cells as a sensitive element, in which the interelectrode current is sensitive to external mechanical influences. New approaches for creating conversion elements are based on precision methods of micromachining materials. The use of new technologies has opened up the possibility of creating sensitive elements with configurations that have not been previously studied, and for which there is no clear understanding of the regularities that determine the output parameters depending on the geometry of the conversion elements. This work studies the influence of the dielectric coating on the surface of the cathodes on the conversion coefficient. The transforming structure has been made from three plates. The outer plates were an anode–cathode electrode pair. The middle plate served as a separator between the pairs of electrodes. It was found that an insulating layer on the side of the cathode facing away from the adjacent anode allows the conversion factor to be doubled. This result is applicable for a wide class of conversion elements made with microelectronic technologies, as well as structures made of mesh electrodes. [ABSTRACT FROM AUTHOR]

The stock‐specific distribution of maturing salmon in the North Pacific has been a persistent information gap that has prevented us from determining the ocean conditions experienced by individual stocks. This continues to impede understanding of the role of ocean conditions in stock‐specific population dynamics. We assessed scale archives for 17 sockeye salmon (Oncorhynchus nerka) stocks covering the entire North Pacific, from the Columbia River (Washington State and British Columbia) to Kamchatka Peninsula (Russia), to infer salmon locations during their last growing season before returning to their spawning grounds. The approach used, first pioneered in salmon stocks in the Atlantic, relies on the relationship between temporal changes in δ13C in salmon scales and sea surface temperature to estimate salmon distribution based on correlation strength. An advantage of this approach is that it does not require fish sampling at sea, but relies on existing fishery agency collections of salmon scales. Significant correlations were found for 7 of the stocks allowing us to propose plausible feeding grounds. Complementary information from δ15N, historical tagging studies, and connectivity analysis were used to further refine distribution estimates. This study is a first step toward estimating stock‐specific distributions of salmon in the North Pacific and provides a basis for the application of the approach to other salmon scale archives. This information has the potential to improve our ability to relate stock dynamics to ocean conditions, ultimately enabling improved stock management. For example, our estimated distributions of Bristol Bay and NE Pacific stocks demonstrated that they occupy different areas with a number of the former being distributed in the high productivity shelf waters of the Aleutian Islands and Bering Sea. This may explain why these stocks seem to have responded differently to changes in ocean conditions, and the long‐term trend of increased productivity of Bristol Bay sockeye. [ABSTRACT FROM AUTHOR]