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The “quantum vampire” effect introduced in Optica2, 112 (2015)OPTIC82334-253610.1364/OPTICA.2.000112 is discussed to understand whether it is really quantum, i.e., based on entanglement and “nonlocality,” or whether photon number correlations are enough. For this purpose, the effect was demonstrated with the classical thermal state of light. We have shown, both theoretically and experimentally, that if a thermal state is distributed among several optical modes, and photon annihilation takes place in one of them, it leads to photon annihilation in the rest of the modes as well. Thus, we conclude, that quantum vampire is actually a classical effect, based on photon number correlations like ghost imaging, Hong-Ou-Mandel interference, and so on.

A search for proteins similar to known synaptonemal complex (SC) proteins of seven higher eukaryote species, from budding yeast to mice (which are widely used as models for the study of meiosis), was conducted in the proteomes of algae, mosses, lower fungi, and Protozoa, using bioinformatics methods. It was established that proteins containing the HORMA domain have the largest similarity with the SC proteins of model organisms in proteomes of green and brown algae, mosses, and a number of lower fungi, as well as Euglenozoa, Sporozoa, and some other unicellular eukaryotes. They are close to the proteins of the lateral elements of the SC of higher eukaryotes that also carry the HORMA domain. This domain recognizes the state of chromatin and recruits other proteins for SC construction.

The mineralogy and structural features of the main types of ferromanganese deposits—nodules, micronodules, Co-bearing crusts, crustlike nodules, and low-temperature hydrothermal manganese crusts and ferruginous ochers—are considered. The correlation between their mineral composition and structure is shown. The proposed classification of mineral types is based on characteristic assemblages of Fe and Mn minerals.

Abstract: A representative collection of hydrothermal sediments was sampled practically from all the hydrothermal mounds of the Broken Spur hydrothermal vent field from the Mir manned submersibles during three cruises of R/V Akademik Mstislav Keldysh. Mineral associations characteristic of different morphological types of sulfide ores from hydrothermal pipes, plates, and diffusers are assessed. Particular attention is paid to the distribution of minor elements and their distribution patterns determined by the mineralogical zonation. The measured isotopic value of the sulfur in the sulfide minerals appeared to vary from 0.4 to 5.2‰, which indicates their similarity with the ores from the Snake Pit vent field and is related to the dilution of hot ore-bearing solutions by seawater and reduction of the water sulfate ions to H2S with a heavy isotopic composition.

New data on the low-temperature hydrothermal deposits of the Snake Pit, TAG, Broken Spur, and Lucky Strike fields in the rift valley of the Mid-Atlantic Ridge (MAR) obtained during the 47th cruise of the R/V Akademik Mstislav Keldyshare reported. These deposits are related to focused and diffuse flows of hydrothermal solutions and the material precipitated from hydrothermal plumes. Electron microscopy study allowed us to identify protoferrihydrite, ferrihydrite, goethite, hematite, Mn-feroxyhyte, and Fe-vernadite. Fe-free vernadite, akaganeite, opal, nontronite, lepidocrocite, and jarosite occur in subordinate amounts. Bacteria-like forms made up of protoferrihydrite particles replaced with ferrihydrite, nontronite, and goethite along with particles of Fe-free vernadite and opal were found. The contents of major, minor, and noble metals were determined in samples with AAS, INAA, and the direct chromatographic method. Elevated PGE contents were established in the low-temperature hydrothermal deposits of the MAR for the first time. The highest PGE contents were detected in the inner zone of Fe-Mn crusts on the surface of a hydrothermal chimney in the Snake Pit field ((ppm) 0.13 Pd, 0.12 Rh, and 0.03 Pt, along with 16.5 Au, 642 Ag, and 355 Se) and in the Au-depleted crust on the surface of a sulfide ore fragment in the Lucky Strike field (0.12 ppm Pd and 0.04 ppm Rh along with 0.03 ppm Au, 683 ppm Se, and 1.5 wt % Ba).

A new method of statistical simulation of quantum systems is presented which is based on the generation of data by the Monte Carlo method and their purposeful tomography with the energy minimisation. The numerical solution of the problem is based on the optimisation of the target functional providing a compromise between the maximisation of the statistical likelihood function and the energy minimisation. The method does not involve complicated and ill-posed multidimensional computational procedures and can be used to calculate the wave functions and energies of the ground and excited stationary sates of complex quantum systems. The applications of the method are illustrated.

Abstract: Two genetically different types of authigenic carbonate mounds are studied: those within an active hydrothermal field related to serpentinite protrusions in the zone of intersection of a transform fracture zone and the Mid-Atlantic Ridge, and those in an active field of methane seepings in the Dnieper canyon of the Black sea. The general geochemical conditions under which authigenic carbonate formation occurs in the two fields considered were found. They include the presence of reduced H2S, H2, and CH4 gases at the absence of free oxygen; the high alkalinity of the waters participating in the carbonate formation; the similarity of the textural and structural features of authigenic aragonite, which represents the initial mineral of the carbonate matter of the mounds; the paragenesis of aragonite with sulfide minerals; and the close relation of carbonate mounds with communities of sulfate-reducing and methane-oxidizing microorganisms. A new mechanism of formation of hydrothermal authigenic carbonates is suggested; it implies their microbial sulfate reduction over the hydrogen of the fluid in the subsurface zone (biosphere) of mixing between the hydrothermal solution and the adjacent seawater.

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The extraction of Schmidt modes for continuous-variable systems is considered. An algorithm based on the singular-value decomposition of a matrix is proposed. It is applied to the entanglement in (i) an atom—photon system with spontaneous emission and (ii) a system of biphotons with spontaneous parametric downconversion (SPDC) of type II. For the atom—photon system, the evolution of entangled states is found to be governed by a parameter approximately equal to the fine-structure constant times the atom-to-electron mass ratio. An analysis is made of the dynamics of atom—photon entanglement on the assumption that the system’s evolution is determined by the superposition of an initial and a final state. It is shown that in the course of emission the entanglement entropy first rises on a timescale of order the excited-state lifetime and then falls, approaching asymptotically a residual level due to the initial energy spread of the atomic packet (momentum spread squared). SPDC of type II is analyzed by means of the polarization density matrix and a newly introduced coherence parameter for two spatially separated modes. The loss of intermodal coherence is addressed that results from the difference in behavior between ordinary-and extraordinary-ray photons in a nonlinear crystal. The degree of intermodal coherence is investigated as a function of the product of crystal length and pump bandwidth.

A hierarchical approach to the construction of compound distributions for process-induced faults in IC manufacture is proposed. Within this framework, the negative binomial distribution and the compound binomial distribution are treated as level-1 models. The hierarchical approach to fault distribution offers an integrated picture of how fault density varies from region to region within a wafer, from wafer to wafer within a batch, and so on. A theory of compound-distribution hierarchies is developed by means of generating functions. With respect to applications, hierarchies of yield means and yield probability-density functions are considered and an in-process measure of yield loss is introduced. It is shown that the hierarchical approach naturally embraces the Bayesian approach.

The published principles of computer analysis of genomes and protein sets in taxonomically distant eukaryotes are expounded. The authors developed a search strategy to identify in genomes of such organisms genes and proteins nonhomologous in primary structure but having similar functions in cells dividing by meiosis. This strategy based on the combined principles of genomics, proteomics, and morphometric analysis of subcellular structures was applied to a computer search for genes encoding the proteins of synaptonemal complexes in genomes of Drosophila melanogaster, the nematode Caenorhabditis elegans, and the plant Arabidopsis thaliana.These proteins proved to be functionally similar to their counterparts in yeast Saccharomyces cerevisiae(protein Zip1p) and mammals (protein SCP1).

The cytological expression of spontaneous mutation sy2isolated from a population of weedy rye was examined. It was demonstrated that the primary defect of meiosis in the mutant plants is nonhomologous synapsis, which occurs simultaneously with the homologous one. An electron microscope study of the synaptonemal complex (SC) at prophase I showed synaptic abnormalities that were manifested as “switches” of synapting axial elements to the nonhomologous partner and the formation of foldbacks of lateral SC elements. The sy2mutants are characterized by one to two such events per meiocyte. Nonhomologous synapsis leads to the appearance of univalents at metaphase I (on average 4.16 ± 0.002 per meiocyte) and multivalents (on average 0.12 ± 0.007 per meiocyte). The presence of multivalents in 12% of meiocytes at metaphase I may result from recombination in ectopic regions of homology. It is suggested that the sy2mutation impairs a component of the system that limits synapsis in meiocytes to only homologous chromosome pairs.

From data on the molecular organization of transverse filament proteins of the synaptonemal complex (SC)—Zip1 in yeast and SCP1 in mammals—and on the width of the SC central space in these organisms and in Drosophila, the putative molecular structure and size of a transverse filament protein of the SC in Drosophilahas been inferred. Using genetic and molecular databases and software from the Internet, we carried out in silicoscreening for a candidate gene for the Drosophilatransverse filament protein. As a most likely candidate, gene c(3)Gwas chosen. The search in the 250-kb region overlapping the locus of this gene (sections 88E-89B) and containing 78 predicted genes has revealed only one gene,CG17604, whose protein meets all requirements for the transverse filament protein of the SC. It was suggested that gene CG17604is gene c(3)G.In this case, genec(3)Gmust be localized in section 89A7-8 of the cytological map of Drosophila melanogaster.

The structure of synaptonemal complexes (SCs) of chromosomes of mouse primary spermatocytes were studied using electron microscopy on days 1, 10, and 36 after the completion of per osadministration of drugs belonging to three groups of antibiotics: tetracyclins, macrolides, and fluoroquinolones. The antibiotics were administered to mice during ten days. At the substages of early and middle pachytene, heteromorphic SC bivalents and fragments of chromosome-core elements were detected in spermatocytes at all times studied after the administration of the antibiotics of three groups. As cells passed through the period from early to middle pachytene, the number of cells containing heteromorphic SC bivalents and the fragments of axial cores gradually decreased, which could be an indication of selection of cells with chromosomal aberrations. A high level of associations between the X chromosome and autosome bivalents (including heteromorphic ones) also favors this suggestion. A gradual decrease in the number of chromosomal aberrations was detected, as time elapsed from the completion of antibiotics administration. The study of sperm obtained from epididymises of males did not reveal significant differences in both morphology and motility of sperm between males of the control and experimental groups.

Analysis of manifestation and inheritance of a new mutation inducing irregular synapsis in rye showed that abnormal phenotype is determined by a recessive allele of the sy19gene. In the homozygotes for this mutation, even at the light microscopic level, abnormal formation of bivalents is already observed at pachytene–diakinesis. At metaphase I, the univalent frequency varies from 0 to 14; in a few cells, multivalent associations of chromosomes, which are not clearly oriented in the spindle, are detected. Electron microscopy of synaptonemal complexes revealed both homologous and heterologous synapsis in homozygotes for sy19, namely partial loss of the ability to stringent homology search. Analysis of joint inheritance of sy19and asynaptic sy1mutations showed that they are nonallelic, inherited independently, and interact by recessive epistasis. The phenotype of doublesy1sy19mutants indicates that thesy19gene conditioning heterologous synapsis operates at meiosis later than the synaptic gene sy1. The epistatic group of mutations, sy9 > sy1 > sy19and sy3, was determined.

Authigenic carbonates in the caldera of an Arctic (72°N) submarine mud volcano with active CH4bearing fluid discharge are formed at the bottom surface during anaerobic microbial methane oxidation. The microbial community consists of specific methane-producing bacteria, which act as methanetrophic ones in conditions of excess methane, and sulfate reducers developing on hydrogen, which is an intermediate product of microbial CH4oxidation. Isotopically light carbon (δ13Cav=−28.9%0) of carbon dioxide produced during CH4oxidation is the main carbonate carbon source. Heavy oxygen isotope ratio (δ18Oav= 5%0) in carbonates is inherited from seawater sulfate. A rapid sulfate reduction (up to 12 mg S dm−3day−1) results in total exhausting of sulfate ion in the upper sediment layer (10 cm). Because of this, carbonates can only be formed in surface sediments near the water-bottom interface. Authigenic carbonates occurring within sediments occur do notin situ.Salinity, as well as CO32−/Ca and Mg/Ca ratios, correspond to the field of nonmagnesian calcium carbonate precipitation. Calcite is the dominant carbonate mineral in the methane seep caldera, where it occurs in the paragenetic association with barite. The radiocarbon age of carbonates is about 10000 yr.

A thread-like (more than 70 cm long) testis of Ascaris suum, when examined under the light and electron microscope, reveals the linear succession of meiotic stages. Beginning from, at least, late leptotene, the spermatocytes are synchronous in their development. Thus within each transverse section of the testis all the spermatocytes are in the same stage. The spermatocytes at each stage of prophase I occupies several (4 to 10) cm of the whole testis length. — At leptotene, synaptonemal-like polycomplexes of lateral and central stacked elements are formed in the cytoplasm of spermatocytes. At late leptotene, the polycomplexes are attached to the external nuclear membrane. The polycomplexes disappear at zygotene. Slightly discernable axial cores are observed in the late leptotene chromosomes. The synaptonemal complexes (SCs) are formed at the zygotene stage, their structure being characteristically tripartite. The SCs disappear from the nuclei at the diffuse stage of prophase I. In other organisms completely developed polycomplexes of stacked lateral and central elements were never found during the presynaptic period of meiosis, although single or two parallel layers of aggregated central regions of SC were found in Neottiella meiocytes at the stage prior to chromosome pairing (Westergaard and von Wettstein, 1970, 1972). — First appearance of the polycomplexes in the cytoplasm insetead of the nucleus is also a novel fact. It is concluded that the polycomplexes at leptotene are formed by a self-assembly of the SC molecular material precociously synthesized in the cytoplasm. Two hypotheses regarding possible function and the further fate for leptotene polycomplexes are discussed.

Abstract: A search for genes specifically expressed in the giant interneurons of parietal ganglia of the snailHelix lucorum yielded, among others, two genes named HDS1 and HDS2. According to data obtained by Northern hybridization and whole-mountin situ hybridization, both genes are neurospecific and expressed almost exclusively in the peptidergic D-group neurons (Sakharov, 1974) located in the right parietal ganglion.In situ hybridization of the HDS1 and HDS2 probes with CNS of several related species of the Helicoidea superfamily identified in all cases similarly located homologous groups of neurons. Sequencing of the near full-length cDNA copies of the HDS1 and HDS2 genes revealed open reading frames 107 and 102 amino acids long for HDS1 and HDS2, respectively. Both putative proteins contain a hydrophobic leader peptide and putative recognition sites for furin-like and PC-like endopeptidases. Predicted amino acid sequences of the HDS1 and HDS2 proteins were found to be moderately homologous to each other, as well as to the LYCP preprohormone expressed by the light yellow cells of the freshwater snailLymnaea stagnalis. These results confirm an earlier hypothesis that the D-group of theHelix family and the light yellow cells ofLymnaea stagnalis represent homologous neuronal groups. Our data suggest that the HDS1 and HDS2 genes encode precursors of secreted molecules, most likely neuropeptides or neurohormones.

Several hydrothermal fields, active and inactive, in the spread-ing center of the Manus backarc basin were discovered, mapped, and sampled using Mir manned submersibles deployed from the R/V Akademik Mstislav Keldysh. In mineral and chemical composition and lateral zoning, these back-arc basin deposits are indistinguishable from those at hydro-thermal fields on median rifts in the open ocean. They are dominated by zinc sulfides; copperrich ores which might be expected in the highest-temperature parts of the field are perhaps being deposited within the underlying volcanic section.

The mineralogy of active chimneys of the Vienna Woods ore field described in the preceding paper has been studied in detail. Predominant minerals are zinc sulfides (sphalerite and wurtzite), iron disulfude (pyrite and marcasite), amorphous silica, and barite, with lesser amounts of chalcopyrite and galena. The sulfide ores are enriched in silver and antimony, apparently occurring in the form of micrometer-size sulfosalts. Two mineral assemblages have been recognized: the earlier one consists of pyrite, sphalerite (or wurtzite) and chalcopyrite, and the later one includes marcasite, pyrite, sphalerite, galena and sulfosalts. The sulfide minerals display considerable variations in δ34S values, from -4.7 to +6.0‰. The ores were formed below 270° C at pH 4-5 as higher-temperature fluids mixed with seawater.