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Bridgmanite, the most abundant mineral in the lower mantle, can play an essential role in deep-Earth hydrogen storage and circulation processes. To better evaluate the hydrogen storage capacity and its substitution mechanism in bridgmanite occurring in nature, we have synthesized high-quality single-crystal bridgmanite with a composition of (M g 0.88 F e 0.05 2 + F e 0.05 3 + A l 0.03) (S i 0.88 A l 0.11 H 0.01) O 3 at nearly water-saturated environments relevant to topmost lower mantle pressure and temperature conditions. The crystallographic site position of hydrogen in the synthetic (Fe,Al)-bearing bridgmanite is evaluated by a time-of-flight single-crystal neutron diffraction scheme, together with supporting evidence from polarized infrared spectroscopy. Analysis of the results shows that the primary hydrogen site has an OH bond direction nearly parallel to the crystallographic b axis of the orthorhombic bridgmanite lattice, where hydrogen is located along the line between two oxygen anions to form a straight geometry of covalent and hydrogen bonds. Our modeled results show that hydrogen is incorporated into the crystal structure via coupled substitution of Al3+ and H+ simultaneously exchanging for Si4+, which does not require any cation vacancy. The concentration of hydrogen evaluated by secondary-ion mass spectrometry and neutron diffraction is ~0.1 wt% H2O and consistent with each other, showing that neutron diffraction can be an alternative quantitative means for the characterization of trace amounts of hydrogen and its site occupancy in nominally anhydrous minerals. [ABSTRACT FROM AUTHOR]

In this paper, we propose an exact method of directly synthesizing a nearest neighbor compliant (NNC) quantum circuit with the smallest depth in 2-D architecture, given a reversible function. Our method maps the synthesis problem to a Boolean satisfiability (SAT) problem and uses a satisfiability modulo theories (SMT) solver to find an assignment of a network of allowed quantum gates. Since an SMT solver performs an exhaustive search, it can be ensured that on a specific qubit placement, the NNC quantum circuit synthesized by our method has the smallest number of quantum gates. However, the exhaustive search also makes our exact method not scale well. For that reason, we propose another method of applying our exact method in the local synthesis of large-scale circuits, to in parallel synthesize sub-NNC quantum circuits. From the experimental results, the quantum costs of the NNC quantum circuits synthesized by our methods are reduced by an average of 23.89%, when compared to an optimal heuristic method which determines the smallest number of SWAP gates in 2-D architecture. [ABSTRACT FROM AUTHOR]

Water speciation in the sodium disilicate melts containing 1.3–8.1 wt.% of total water was studied by near-infrared spectroscopy at 900 °C and pressures from 0.2 to 1.7 GPa using externally heated diamond anvil cell. Hydrous sodium disilicate melt served both as a sample and as a pressure medium in the experiments, which allowed to keep the total water content of the melt constant and thereby to perform an internally consistent calibration of molar absorption coefficients for the near-infrared bands of water species. No pressure dependence of water speciation was observed in the studied pressure range, indicating that formation of structurally bound OH groups at the expense of H 2 O molecules in the melt is accompanied by a negligible volume change. At 900 °C, compositional dependence of water speciation was found to be much weaker than that expected from the previously reported data for low-temperature range near the glass transition. This can be explained by significant weakening of hydrogen bonding in the sodium silicate melts at high temperatures. [ABSTRACT FROM AUTHOR]

Digital microfluidic biochips have become one of the most promising technologies for biomedical experiments. In modern microfluidic technology, reducing the number of independent control pins that reflects most of the fabrication cost, power consumption, and reliability of a microfluidic system, is a key challenge for every digital microfluidic biochip design. However, all the previous chip designs sacrifice the optimality of the problem, and only limited reduction on the number of control pins is observed. Moreover, most existing designs cannot satisfy high-throughput demand for bioassays, and thus inapplicable in practical contexts. In this paper, we propose the first optimal pin-count design scheme for digital microfluidic biochips. By integrating a very simple combinational logic circuit into the original chip, the proposed scheme can provide high-throughput for bioassays with an information-theoretic minimum number of control pins. Furthermore, to cope with the rapid growth of the chip’s scale, we also propose a scalable and efficient heuristics to reduce the number of control pins. A logic optimization technique, which can be used to reduce the complexity of the integrated combinational logic circuit, is also presented in this paper. Experiments demonstrate that the proposed scheme can obtain much fewer number of control pins compared with the previous state-of-the-art works. [ABSTRACT FROM PUBLISHER]

Polycrystalline, cubic 13C diamond was synthesized from amorphous carbon in the Kawai-type multianvil apparatus at 21 GPa and at a temperature greater than 2350°C. The polycrystalline diamond was homogeneous with a small grain size (10–20 μm) and a sharp Raman peak, and thereby was suitable as a pressure sensor for the experiments in a hydrothermal diamond anvil cell. Pressure- and temperature-dependence of the Raman shift of the synthesized 13C diamond was investigated in situat simultaneous high pressures and high temperatures in the hydrothermal diamond anvil cell, using the ruby fluorescence line, quartz Raman shift and H2O phase transitions as pressure references. It was observed that the frequency shift with pressure is independent of temperature and vice versaup to 500°C and 4.2 GPa. The present study indicates that the 13C diamond Raman shift can be used for pressure determination with an accuracy better than ±0.3 GPa under the conditions examined. [ABSTRACT FROM AUTHOR]

Xenopus egg extracts execute spontaneous apoptosis without the requirement of transcription and translation, and this intrinsic mechanism is supposed to be involved in the physiological elimination of aged eggs. Although apoptosis in this system is carried out by maternally stockpiled materials, the endogenous apoptosis regulators present in egg extracts are still poorly characterized. Here we examined the mRNA expression profiles and apoptosis-regulating functions of 13 Xenopus Bcl-2 family proteins in egg extracts. Among these, we found that endogenous Xenopus Mcl-1 (xMcl-1) physiologically inhibited apoptosis by counteracting the pro-apoptotic activity of endogenous Xenopus Bid in egg extracts. Exogenously added recombinant xMcl-1 was rapidly degraded by proteasome in egg extracts, and we identified the destabilizing region in the N terminus of xMcl-1. Our results suggest that the proteolytic decay of xMcl-1 may change the functional balance between pro- and anti-apoptotic activities of Bcl-2 family proteins, thereby regulating the timing of cytochrome c release in egg extracts. [ABSTRACT FROM AUTHOR]

Abstract: The structure of silicate melts in the system Na2O·4SiO2 saturated with reduced C–O–H volatile components and of coexisting silicate-saturated C–O–H solutions has been determined in a hydrothermal diamond anvil cell (HDAC) by using confocal microRaman and FTIR spectroscopy as structural probes. The experiments were conducted in-situ with the melt and fluid at high temperature (up to 800°C) and pressure (up to 1435MPa). Redox conditions in the HDAC were controlled with the reaction, Mo+H2O=MoO2 +H2, which is slightly more reducing than the Fe+H2O=FeO+H2 buffer at 800°C and less. The dominant species in the fluid are CH4 +H2O together with minor amounts of molecular H2 and an undersaturated hydrocarbon species. In coexisting melt, CH3 – groups linked to the silicate melt structure via Si–O–CH3 bonding may dominate and possibly coexists with molecular CH4. The abundance ratio of CH3 – groups in melts relative to CH4 in fluids increases from 0.01 to 0.07 between 500 and 800°C. Carbon-bearing species in melts were not detected at temperatures and pressures below 400°C and 730MPa, respectively. A schematic solution mechanism is, Si–O–Si+CH4⇌Si–O–CH3+H–O–Si. This mechanism causes depolymerization of silicate melts. Solution of reduced (C–O–H) components will, therefore, affect melt properties in a manner resembling dissolved H2O. [Copyright &y& Elsevier]

Abstract: Changes of near-infrared (NIR) absorption peaks at ~4500 cm−1 due to SiOH groups and at ~5200 cm−1 due H2O molecules upon heating were investigated in sodium tetrasilicate glasses (Na2O·4SiO2, 1.0–5.2 wt.% H2O) and sodium hexasilicate glasses (Na2O·6SiO2, 2.3–7.0 wt.% H2O) at ambient pressure. Temperature was varied between 25 °C and 475 °C using a heating stage fitted to a Fourier-transform micro-infrared spectrometer. Dissolved water is stable in the glasses during such a heat treatment as evidenced by NIR spectra recorded after heating. Changes in the spectra below 200 °C are assigned to decreasing hydrogen bonding of water species and to the T-dependence of the molar absorption coefficients for the NIR combination bands. At higher temperature a rapid increase in intensity of the 4500 cm−1 band on expense of the 5200 cm−1 band was observed indicating the onset of species interconversion Si–O–Si+H2O=2Si–OH. The onset temperature for these changes increase with decreasing total water content of the glasses. Water species concentrations could not be determined directly from the intensities of the NIR combination bands for the melt because the molar absorption coefficients cannot be calibrated for the sodium silicate melts at high temperatures. Therefore, the heating experiments were used only to determine the fictive temperatures (also denoted as apparent equilibrium temperatures) for the water speciation measured on the glasses at room temperature. Assuming ideal mixing of quasi-oxygen species (OH group, H2O molecule, non-bridging oxygen NBO, bridging oxygen BO) the equilibrium constant K for interconversion reaction of water species was calculated. The temperature dependence of the speciation equilibrium in the melt state can be expressed by ln K =5.39–3427/ T for sodium tetrasilicate and ln K =5.80–3731/ T for sodium hexasilicate. At magmatic temperatures the equilibrium constant for water speciation in sodium silicate melts is larger than in polymerized aluminosilicate melts by a factor of 5 or more, depending on melt composition. This large difference of ln K is most likely owing to the high degree of melt depolymerization and the high alkali concentration in sodium silicate melts. [Copyright &y& Elsevier]

Abstract: Water speciation in hydrated Na2O·2SiO2 (NS2), Na2O·4SiO2 (NS4), and Na2O·6SiO2 (NS6) glasses was analyzed by near-infrared (NIR) spectroscopy and low temperature static 1H nuclear magnetic resonance (NMR) spectroscopy. For each composition 6–9 glasses containing between 0.5 and 7.0 wt.% total water (measured by Karl–Fischer titration) were used to calibrate the molar absorption coefficients for the NIR combination bands near 4500 cm−1 (OH groups) and near 5200 cm−1 (H2O molecules). Noticeable disagreement was found between the water speciation derived from NIR spectra using an internally consistent calibration based on total water content and the water speciation determined by 1H NMR spectroscopy. The discrepancies are more pronounced for the evaluation of NIR peak areas (differences up to 55% in OH group content) than for the evaluation of peak heights (differences up to 35% in OH group content). Based on the NMR data we performed a new calibration for the NIR combination bands of the hydrous sodium silicate glasses. The molar absorption coefficients for the 4500 cm−1 band (ε 4500) and the 5200 cm−1 band (ε 5200) noticeably decrease with increasing Na2O content of the glasses from NS6 to NS2. The ε values for both bands also decrease with total water content in NS4 and NS6 glasses. The variation of ε values may be due to changes in the relative abundance of water subspecies, i.e. species exposed to strong or weak hydrogen bonding. Another explanation could be an incomplete separation of the combination bands from the tail of the fundamental OH stretching vibration bands and from the unassigned water-related band at 4000 cm−1. Using the NMR-supported NIR calibration we calculated water species concentrations in the sodium silicate glasses as a function of total water content. At a total water content of 6.0 wt.%, the amount of water dissolved as OH groups is noticeably higher in the depolymerized glasses NS2 and NS4 (∼3.0 wt.%) than in the less depolymerized NS6 (∼2.5 wt.%). This observation implies that non-bridging oxygen, charge-compensated by sodium, promotes the formation of OH groups. No significant difference in water speciation was found between rapidly quenched glasses (∼150 K/s) and more slowly cooled glasses (∼2 K/s). [Copyright &y& Elsevier]

This paper gives a simple but nontrivial set of local transformation rules for CNOT-based quantum circuits. It is shown that this rule set is complete, namely for any two equivalent circuits, S1andS2 , there is a sequence of transformations, each of them in the rule set, which changesS1 to S2. This rule set can be used for incremental circuit optimization methods like the classical circuit design methodology. [Copyright &y& Elsevier]

Proposes a way to express functional flexibility by using sets of pairs of functions called sets of pairs of functions to be distinguished (SPFD). Other concepts for expressing functional flexibility; Definitions related to SPFD; Comparison between SPFD and the compatible sets of permissible functions.

We have conducted electrical conductivity measurements of FeCO3 siderite under high pressure up to 63 GPa in order to understand the nature and effect of iron spin transition and its influence on the geophysical properties of siderite, which is an end-member of major carbonate minerals. The results from Raman and Mössbauer spectroscopic measurements show that the high- to low-spin transition of iron occurs at around 50 GPa in agreement with previous studies. A sharp decrease of the electrical conductivity was also observed at around 50 GP, which is associated with the spin transition in iron. Although the stability of FeCO3 siderite may be limited under high-temperature conditions along with the mantle geotherm, solid solutions in the MgCO3-FeCO3 system, Mg1-xFexCO3, could be stable up to the pressure-temperature condition of the lowermost mantle. The pressure-temperature range of the spin transition in Mg1-xFexCO3 is narrower than those of the major lower mantle minerals, ferropericlase and bridgmanite, and thus the drop of the electrical conductivity induced by the spin transition could be clearer under lower mantle conditions. Therefore, the existence of Mg1-xFexCO3 may affect the observed heterogeneity of electrical conductivity in the mid-lower mantle. [ABSTRACT FROM AUTHOR]

The effect of temperature on water solubility in rhyolite melt was experimentally determined at 850-1200°C and 22-100 MPa. A natural high-silica rhyolite glass was equilibrated with pure water vapor, and the water content in the quenched glass was determined by IR spectroscopy. The results demonstrate that water solubility in rhyolite melt has a negative temperature dependence, which becomes weaker at high temperatures and low water contents. This temperature dependence can be modeled adequately on the basis of ideal mixing of water species and anhydrous rhyolite melt components. The model reproduces both the present and previously published solubility data for water in rhyolitic melts to 100 MPa and over a wide range of temperature from near the solidus to 1200°C, thereby permitting calculation of water saturation under varying temperature conditions. At 50-100 MPa, an increase in the fraction of excess water as a result of a rise in temperature can cause a four- to eight-fold increase in the fractional amount of volumetric expansion above that caused by pure thermal expansion, per unit temperature rise. Thus, the negative temperature dependence of water solubility could be of fundamental importance in the development of gravitational instability in shallow, water-saturated silicic magma chambers. [ABSTRACT FROM PUBLISHER]

BackgroundThe replication licensing factor limits DNA replication to once in a cell cycle and is thought to contain MCM proteins as its component parts. Six MCM subtypes have been identified in various species. These MCM proteins are thought to bind each other to make a heteromeric complex. The Nda4 protein of Schizosaccharomyces pombe is one of the MCM proteins and is involved in DNA replication. ResultsThe suppressor mutant of nda4 was isolated and the mutant gene was named sna41. The sna41-912 mutant demonstrated the ts phenotype, with an elongated cell shape at the restrictive temperature. Cells with 1C DNA content accumulated 2 h after shifting up to the restrictive temperature. This result suggests that sna41 is also involved in DNA replication. The sna41 genomic clone was isolated by a complementation of the ts phenotype of the mutant strain and was sequenced. The sna41 gene encodes a protein of 638 amino acids, which has low homology with CDC45 in S. cerevisiae. The gene disruption analysis showed that sna41 gene is essential for viability. ConclusionsThe S. pombe sna41 mutation suppresses the nda4-108 mutation. Sna41 is involved in DNA replication and may play some roles in the regulation of DNA replication by the MCM proteins. [ABSTRACT FROM AUTHOR]

A continuous section through an 811 m-thick lava pile of mid-ocean ridge basalts at Integrated Ocean Drilling Program Site 1256 provides important constraints on the variation with depth of volatile element (H 2 O, CO 2 , S and Cl) contents in fresh matrix glasses to understand evolution of magma, condition of magma ascent, and degree of hydrothermal assimilation. The lava pile is divided into two groups based on eruption location: off-axis basalts of upper portion (250–534 m beneath seafloor, mbsf) and on-axis basalts of lower portion (534–1061 mbsf). The lava pile is composed of pillow, sheet, and massive lavas that include thin (<2 m) hyaloclastite intervals. Variations of H 2 O and major element contents in Site 1256 matrix glasses can be explained by fractional crystallization of one primitive basalt (MgO, 7.7 wt%) at the pressure of a melt lens (top of axial magma chamber). CO 2 /Nb and S/Dy in a large majority of fresh matrix glasses are lower than undegassed ratios, and these facts indicate that CO 2 and S losses occurred during differentiation within the melt lens and/or magma transport to the seafloor. Saturation pressures calculated from dissolved CO 2 and H 2 O contents give a wide range of pressures from seafloor (~25 MPa) to axial magma chamber (~60 MPa). Many off-axis glasses have saturation pressures of seafloor, but on-axis glasses have high saturation pressures up to axial magma chamber depths. The saturation pressures of off-axis glasses decrease with decreasing depth (i.e., with increasing distance from the axis). These observations indicate that the many off-axis glasses were highly degassed because their source magmas travelled for long time periods from melt lens to off-axis seafloor locations. On the other hand, on-axis glasses were less degassed because magma transport times to on-axis locations were shorter than those for off-axis locations. The most distinctive characteristic for the Site 1256 glasses is their higher Cl/Nb than any other mid-ocean ridge basalt glasses. The strong Cl enrichment is explained by assimilation of hydrothermal brines. Beneath Site 1256, the melt lens was very shallow (<1.2 km) and hydrothermal circulation of high-salinity brines with variable salinities would reach easily to the melt lens. Unlabelled Image • H 2 O, CO 2 , S and Cl contents in MORB glasses from IODP Site 1256 lavas are presented. • H 2 O content in magma was increased by fractional crystallization within a melt lens. • Off-axis glasses were highly CO 2 degassed due to long travel times before eruption. • On-axis glasses were less CO 2 degassed due to short travel times before eruption. • Site 1256 basalts have the most Cl-rich compositions among MORB glasses worldwide. [ABSTRACT FROM AUTHOR]

Digital microfluidic biochips (DMFBs), which are used in various fields like DNA analysis, clinical diagnosis, and PCR testing, have made biochemical experiments more compact, efficient, and user-friendly than the previous methods. However, their reliability is often compromised by their inability to adapt to all kinds of errors. Errors in biochips can be categorized into two types: known errors, and unknown errors. Known errors are detectable before the start of the routing process using sensors or cameras. Unknown errors, in contrast, only become apparent during the routing process and remain undetected by sensors or cameras, which can unexpectedly stop the routing process and diminish the reliability of biochips. This paper introduces a deep reinforcement learning-based routing algorithm, designed to manage not only known errors but also unknown errors. Our experiments demonstrated that our algorithm outperformed the previous ones in terms of the success rate of the routing, in the scenarios including both known errors and unknown errors. Additionally, our algorithm contributed to detecting unknown errors during the routing process, identifying the most efficient routing path with a high probability. [ABSTRACT FROM AUTHOR]

The solubility and solution mechanisms of nitrogen in silicate melts have been examined via nitrogen analyses and vibrational spectroscopy (Raman and FTIR). Pressure (P), temperature (T), hydrogen fugacity (fH2), and silicate melt composition (degree of melt polymerization) were independent variables in experiments in the 1-2.5 GPa pressure and 1300-1500 °C temperature ranges. The fH2 was controlled at values defined by the magnetite-hematite (MH), Mn3O4-MnO (MM), NiO-Ni (NNO), magnetite-wustite (MW), and iron-wustite (IW) buffers together with H2O. The nitrogen solubility ranges from about 1 to about 5 mol%, calculated as N, with ∂XN/∂P > 0 and ∂XN/∂fH2 > 0. The ∂/∂fH2(∂XN/∂P) is also positive. Raman and FTIR spectroscopic data are consistent with solution mechanisms that involve reduction of nitrogen with increasing fH2. At low fH2 [fH2(MH) and fH2(MM)], nitrogen is dissolved in melts only as molecular N2. At fH2(NNO) and fH2(MW), there is partial reduction of nitrogen to form N2, NH2+ complexes and molecular NH3 in the melts, whereas at the highest fH2(IW), only molecular NH3 and NH-2 groups can be identified. OH groups are also formed whenever there is reduction of nitrogen from N2. Solution in silicate melts of reduced, NH-bearing species results in silicate melt depolymerization. At fH2(NNO) and fH2(MW), depolymerization occurs via H+ interaction with oxygen and NH+2 groups serving as network-modifier. Under more reducing conditions, oxygen is replaced by NH-2 groups. Solution of reduced nitrogen in silicate melts causes depolymerization of their structure. This implies that melt properties that depend on silicate structure depend on redox conditions. [ABSTRACT FROM AUTHOR]

When intracellular damage accumulates in proliferating somatic cells, the cell cycle usually arrests in G1 or G2 in a checkpoint-dependent manner, either to repair the damage or to die by apoptosis. In contrast, early embryonic cells lack checkpoint-mediated cell-cycle arrest, and it is not clear whether apoptosis in early embryonic cells occurs at a specific cell cycle stage or at random points. Here, we examined the functional molecular link between the embryonic cell cycle and apoptosis using Xenopus egg extracts. When apoptosis was induced in egg extracts by addition of exogenous cytochrome c during cell-cycle progression, cyclin B accumulation was inhibited, Cdc2 was not activated, and the cell cycle arrested at interphase. However, addition of recombinant cyclin B failed to activate Cdc2 due to the strong inhibitory phosphorylation of Cdc2 Tyr15 in apoptotic egg extracts. We found that endogenous Cdc25C, which activates the Cdc2-cyclin B complex by dephosphorylating Cdc2 Tyr15, was inactivated by caspase-mediated cleavage at two sites in the N-terminal regulatory domain. When the hyperactive Cdc25A catalytic fragment was added together with recombinant cyclin B to artificially dephosphorylate Cdc2 Tyr15, M-phase induction was restored in apoptotic egg extracts, indicating that the blockage of cyclin B accumulation and the caspase-mediated inactivation of Cdc25C dually inhibited Cdc2 activation. Apoptosis induction in cytostatic factor-arrested metaphase egg extracts resulted in inactivation of Cdc2 without cyclin B degradation. These results suggest that apoptotic inactivation of Cdc25C plays an important role in arresting the embryonic cell cycle at interphase during apoptosis. [ABSTRACT FROM AUTHOR]

Cdc7 is an S-phase-promoting kinase (SPK) that is required for the activation of replication initiation complex assembly because it phosphorylates the MCM protein complex serving as the replicative helicase in eukaryotic organisms. Cdc7 activity is undetectable in immature mouse GV oocytes, although Cdc7 protein is already expressed at the same level as in mature oocytes or early one-cell embryos at zygotic S-phase, in which Cdc7 kinase activity is clearly detectable. Dbf4 is a regulatory subunit of Cdc7 and is required for Cdc7 kinase activity. Dbf4 is not readily detectable in immature GV oocytes but accumulates to a level similar to that in one-cell embryos during oocyte maturation, suggesting that Cdc7 is already activated in unfertilized eggs (metaphase II). RNAi-mediated knockdown of maternal Dbf4 expression prevents the maturation-associated increase in Dbf4 protein, abolishes the activation of Cdc7, and leads to the failure of DNA replication in one-cell embryos, demonstrating that Dbf4 expression is the key regulator of Cdc7 activity in mouse oocytes. Dormant Dbf4 mRNA in immature GV oocytes is recruited by cytoplasmic polyadenylation during oocyte maturation and is dependent on MPF activity via its cytoplasmic polyadenylation element (CPE) upstream of the hexanucleotide (HEX) in the 3′ untranslated region (3′UTR). Our results suggest that Cdc7 is inactivated in immature oocytes, preventing it from the unwanted phosphorylation of MCM proteins, and the oocyte is qualified by proper maturation to proceed following embryogenesis after fertilization through zygotic DNA replication. [ABSTRACT FROM AUTHOR]

The oceanic asthenosphere is observed to have high electrical conductivity, which is highly anisotropic in some locations. In the directions parallel and normal to the plate motion, the conductivity is of the order of 10-1 and 10-2 S m-1, respectively, which cannot be explained by the conductivity of anhydrous olivine. But because hydrogen can be incorporated in olivine at mantle pressures, this observation has been attributed to olivine hydration, which might cause anisotropically high conductivity by proton migration. To examine this hypothesis, here we report the effect of water on electrical conductivity and its anisotropy for hydrogen-doped and undoped olivine at 500–1,500 K and 3 GPa. The hydrous olivine has much higher conductivity and lower activation energy than anhydrous olivine in the investigated temperature range. Nevertheless, extrapolation of the experimental results suggests that conductivity of hydrous olivine at the top of the asthenosphere should be nearly isotropic and only of the order of 10-2 S m-1. Our data indicate that the hydration of olivine cannot account for the geophysical observations, which instead may be explained by the presence of partial melt elongated in the direction of plate motion. [ABSTRACT FROM AUTHOR]

In many animal species includingXenopus, ovulated eggs possess an intrinsic apoptotic execution system. This program is inhibited for a limited time by some maternal apoptosis inhibitors, although their molecular properties remain uncharacterized. Baculovirus IAP repeat (BIR) family proteins contain evolutionarily conserved BIR domains and play important roles in apoptosis suppression, and are therefore good candidates as maternal apoptosis inhibitors. We identified four maternal BIR family proteins inXenopuseggs and, using the biochemical advantages of egg extracts, examined their physiological functions. These molecules included two survivin-related proteins, xEIAP/XLX, and a possible ortholog of XIAP named xXIAP. The addition of recombinant xXIAP greatly delayed apoptotic execution, whereas the immunodepletion of endogenous xXIAP significantly accelerated the onset of apoptosis. In contrast, xEIAP/XLX was a poor apoptosis inhibitor, and neither of the survivin orthologs showed anti-apoptotic activity in our assay. Both xEIAP/XLX and xXIAP were degraded by activated caspases, and also by a novel proteolytic system that required the presence of C-terminal RING finger domain but was insensitive to proteasome inhibition. Our data suggest that the regulation of endogenous xXIAP concentration is important for the survival ofXenopuseggs. [ABSTRACT FROM AUTHOR]

Being a structure like a two-dimensional (2D) array of microvalves and cells, Programmable Microfluidic Device PMD biochips have the characteristics of reconfigurability and flexibility unlike conventional flow-based microfluidic biochips. In recent years, several design automation techniques for PMD biochips have been reported. For automated control of the PMD chip implementing a bioprotocol, one of the important tasks is to minimize the number of fluid flows for loading the reactant fluids into specific cells before the bioprotocol is executed. In this work we intensively study the fluid loading problem for PMD chips and we propose a two-phase approach to solve this problem. First, we propose a constraint satisfaction problem (CSP) based method, called loading-aware fluid-to-cell assignment (LAFCA) in order to obtain a suitable fluid-to-cell assignment, which will be beneficial for fluid loading phase. Then we propose an exact method, called CSP-based loading algorithm (CSPLA) and a near-optimal heuristic method, called determining flows from the last (DFL), for determining a sequence of fluid flows required to load different fluids into the cells of a PMD chip. We formulate CSPLA as a single objective optimization problem to minimize the total number of flows. For the output as a sequence of fluid flows we define three loading parameters, the total number of flows (K), the total number of 90° bends in all flow paths (B), and the total flow path length (L). Simulation results confirm that LAFCA combined with CSPLA outperforms (K , B and L reduced by 63.9%, 31.7% and 59.9%, respectively) the state-of-the-art method fluid loading algorithm for PMD (FLAP) [Gupta et al., TODAES, 2019]. Whereas, LAFCA combined with DFL can reduce the loading parameters K , B and L by 61.2%, 20.8% and 57.4%, respectively over using only FLAP. Also from the overall simulation results we can conclude that for many testcases, DFL can find the near-optimal K s. • As many real-life bioprotocols can be realized on a PMD, design-automation for bioprotocols in PMD are in demand. • We present a method for loading aware fluid-to-cell assignment for implementation of bioprotocols on PMD biochips. • We propose an exact method and a heuristic method for optimizing the of flows for fluid loading in a PMD. [ABSTRACT FROM AUTHOR]

Akita-Komagatake is an active volcano in the Northeast Japan arc with a slab depth (H) of ∼110 km. In this study, magma generation conditions were estimated for basaltic products from the volcano to examine the thermal structure of the sub-arc mantle and the across-arc variations in the parameters related to magma genesis. The studied basalts have the highest MgO content (∼6 wt%) among the products from the volcano and contain ∼15% plagioclase phenocrysts, ∼5% olivine phenocrysts, and <1% pyroxene phenocrysts. The water content of the melt was estimated to be ∼4 wt% by melt inclusions in the phenocrysts using plagioclase–melt hygrometry. Multi-component thermodynamic analyses suggest that the primary magma was generated by ∼14% melting of the source mantle with ∼0.5 wt% H 2 O at ∼1275 °C and ∼1.3 GPa. The estimated pressure condition of ∼1.3 GPa coincides well with the low-velocity anomaly observed in the mantle at ∼40 km depth beneath the volcano. By comparing the results from Akita-Komagatake to the published results of the frontal-arc Iwate volcano (H = ∼90 km) and the rear-arc Sannome-gata volcano (H = ∼150 km), which are arranged along a cross-arc line in the Northeast Japan arc, we found that the pressure conditions of the magma generation are ∼1.3 GPa at both Iwate and Akita-Komagatake, which are significantly lower than the ∼1.8 GPa at the rear-arc Sannome-gata volcano. The source mantle temperature of ∼1275 °C at ∼1.3 GPa beneath Akita-Komagatake is higher than the ∼1250 °C at ∼1.3 GPa beneath Iwate, which suggests that the ascending flow of the mantle wedge corner flow may reach the shallowest levels beneath Akita-Komagatake. It was also demonstrated that the depth at which fluid was released from the subducting slab tends to increase for the volcanoes with increasing H. • Magma generation conditions were estimated for basalts from Akita-Komagatake. • Primary magma was generated by 14% melting of the mantle at 1270 °C and 1.3 GPa. • The estimated melting depth coincides well with the low-Vp anomaly in the mantle. • Many parameters related to magma genesis show significant across-arc variation. [ABSTRACT FROM AUTHOR]

The origin and evolution of solar system bodies, including water on the Earth, have been discussed based on the assumption that the relevant ingredients were simply silicates and ices. However, large amounts of organic matter have been found in cometary and interplanetary dust, which are recognized as remnants of interstellar/precometary grains. Precometary organic matter may therefore be a potential source of water; however, to date, there have been no experimental investigations into this possibility. Here, we experimentally demonstrate that abundant water and oil are formed via the heating of a precometary-organic-matter analog under conditions appropriate for the parent bodies of meteorites inside the snow line. This implies that H2O ice is not required as the sole source of water on planetary bodies inside the snow line. Further, we can explain the change in the oxidation state of the Earth from an initially reduced state to a final oxidized state. Our study also suggests that petroleum was present in the asteroids and is present in icy satellites and dwarf planets. [ABSTRACT FROM AUTHOR]

The identification of threshold function (TF), which determines whether a Boolean function can be represented by an linear threshold logic gate (LTG) or not, is a fundamental but important task in the theories of threshold logic. In this paper, we propose a more efficient and effective algorithm of TF identification by constructing the system of irredundant inequalities and adjusting the weight assignment comprehensively. This is the first non-ILP-based approach that is able to identify all the eight-input TFs. The experimental results demonstrated that the proposed approach is more effective than all the existing non-ILP-based approaches and the LTGs obtained by the proposed approach are optimal for near 100% cases. For TFs with 9–15 inputs, the proposed approach can identify 100 000 randomly generated TFs as well in a reasonable CPU time. [ABSTRACT FROM AUTHOR]

Rationale: The three oxygen isotopes in terrestrial/extraterrestrial silicates can provide geochemical and cosmochemical information about their origin and secondary processes that result from isotopic exchange. A laser fluorination technique has been widely used to extract oxygen from silicates for δ17O and δ18O measurements by isotope ratio mass spectrometry. Continued improvement of the techniques is still important for high‐precision measurement of oxygen‐isotopic ratios. Methods: We adopted an automated lasing technique to obtain reproducible fluorination of silicates using a CO2 laser‐BrF5 fluorination system connected online to an isotope ratio mass spectrometer. The automated lasing technique enables us to perform high‐precision analysis of the three oxygen isotopes of typical reference materials (e.g., UWG2 garnet, NBS28 quartz and San Carlos olivine) and in‐house references (mid‐ocean ridge basalt glass and obsidian). The technique uses a built‐in application of laser control with which the laser power can be varied in a programmed manner with a defocused beam which is in a fixed position. Results: The oxygen isotope ratios of some international reference materials analyzed by the manual lasing technique were found to be isotopically lighter with wider variations in δ18O values, whereas those measured by the automated lasing technique gave better reproducibility (less than 0.2‰, 2SD). The Δ17O values, an excess of the δ17O value relative to the fractionation line, also showed high reproducibility (±0.02‰, 2SD). Conclusions: The system described herein provides high‐precision δ17O and δ18O measurements of silicate materials. The use of the automated lasing technique followed by careful and controlled purification procedures is preferred to achieve satisfactory isotopic ratio results. [ABSTRACT FROM AUTHOR]

For the past 40 years, the Moon has been described as nearly devoid of indigenous water; however, evidence for water both on the lunar surface and within the lunar interior have recently emerged, calling into question this long-standing lunar dogma. In the present study, hydroxyl (as well as fluoride and chloride) was analyzed by secondary ion mass spectrometry in apatite [Ca5(PO4)3(F,Cl,OH)] from three different lunar samples in order to obtain quantitative constraints on the abundance of water in the lunar interior. This work confirms that hundreds to thousands of ppm water (of the structural form hydroxyl) is present in apatite from the Moon. Moreover, two of the studied samples likely had water preserved from magmatic processes, which would qualify the water as being indigenous to the Moon. The presence of hydroxyl in apatite from a number of different types of lunar rocks indicates that water may be ubiquitous within the lunar interior, potentially as early as the time of lunar formation. The water contents analyzed for the lunar apatite indicate minimum water contents of their lunar source region to range from 64 ppb to 5 ppm H2O. This lower limit range of water contents is at least two orders of magnitude greater than the previously reported value for the bulk Moon, and the actual source region water contents could be significantly higher. [ABSTRACT FROM AUTHOR]

Abstract: Mouse oocytes acquire the ability to replicate DNA during meiotic maturation, presumably to ensure that DNA replication does not occur precociously between MI and MII and only after fertilization. Acquisition of DNA replication competence requires protein synthesis, but the identity of the proteins required for DNA replication is poorly described. In Xenopus, the only component missing for DNA replication competence is CDC6, which is synthesized from a dormant maternal mRNA recruited during oocyte maturation, and a similar situation also occurs during mouse oocyte maturation. We report that ORC6L is another component required for acquisition of DNA replication competence that is absent in mouse oocytes. The dormant maternal Orc6l mRNA is recruited during maturation via a CPE present in its 3′ UTR. RNAi-mediated ablation of maternal Orc6l mRNA prevents the maturation-associated increase in ORC6L protein and inhibits DNA replication in 1-cell embryos. These results suggest that mammalian oocytes have more complex mechanisms to establish DNA replication competence when compared to their Xenopus counterparts. [Copyright &y& Elsevier]

Abstract: Apoptosis in Xenopus egg extracts is carried out by maternally stockpiled materials, but the contributions of endogenous apoptosis regulators are still poorly characterized. Here we examined the physiological role of Xenopus Bid (xBid), a pro-apoptotic BH3-only member of Bcl-2 family proteins. We found that endogenous xBid was a physiological accelerator of apoptosis in egg extracts. Interestingly, xBid was mono-/diubiquitylated but not degraded by proteasome in egg extracts, and we identified three ubiquitylated Lys residues in the N-terminal propeptide region. Comparison with human Bid suggested that mono-/diubiquitylation is a specific feature of xBid. [Copyright &y& Elsevier]

Abstract: Electrical conductivity of wadsleyite was measured at 16GPa using a KAWAI-type multi-anvil press under controlled oxygen fugacity. Water-doped and -undoped samples were used to examine the effect of water on conductivity. Two water-doped wadsleyite samples used for the conductivity measurements contained 0.3±0.01 and 1.2±0.02wt.% water. The temperature ranges for the conductivity measurements were 500–2000K for water-undoped samples and 500–1000K for water-doped samples. Above 1500K, the electrical conductivity values are essentially the same among different runs with an average activation enthalpy of 1.5eV, suggesting that small polaron conduction should dominate. Below 1000K, the conductivity systematically increases with increasing water content, suggesting proton conduction as a dominant conduction mechanism. Electrical conductivity of anhydrous wadsleyite in the mantle transition zone should be about 3×10−2 S/m in the normal geotherm. Hydration enhances the conductivity of wadsleyite; by containing 0.1wt. % water, the conductivity of wadsleyite increases by 0.3log units. The conductivity jump associated with the dry olivine–wadsleyite transition is only 0.7log units. A dry olivine–wadsleyite conductivity model well agrees with the current semi-global conductivity-depth profiles, thus the concept of a globally hydrated mantle transition zone is not necessary in view of electrical conductivity. The high conductivity observed in the wedge mantle cannot be explained by hydrous wadsleyite. Alternatively, the presence of either phase E or supercritical fluids in the wedge mantle is proposed. [Copyright &y& Elsevier]

The viability of mammalian eggs after ovulation is reported to be improved by the presence of ascorbic acid in the culture medium. However, the pro-survival mechanisms of ascorbic acid are poorly understood. The molecular pathways of apoptosis are evolutionarily conserved among animal species, and Xenopus eggs are technically and ethically more suitable for biochemical analyses than mammalian eggs. We used Xenopus egg cytoplasmic extracts to examine the direct intracellular effects of ascorbic acid. Incubation of egg extracts for more than 4 h induces the spontaneous release of cytochrome c from mitochondria. This event triggers the activation of caspases, cleavage of substrate proteins, and execution of apoptosis. Multiple signal transduction pathways including proteolysis and protein phosphorylation are also involved in this process. We examined whether any of these events might be inhibited by the addition of ascorbic acid. Ascorbic acid showed no effect against cytochrome c release, but prevented caspase activation and substrate cleavage. Ascorbic acid also blocked the proteolysis of apoptosis inhibitor proteins and the dephosphorylation of p42 MAP kinase. However, dehydroascorbic acid (oxidized form of ascorbic acid) and acetate (unrelated acid) were equally effective, indicating that these effects were primarily due to their acidity. In addition, dehydroascorbic acid inhibited caspase activities directly in vitro. The anti-apoptotic effect of ascorbic acid in Xenopus egg extracts is mainly due to cytoplasmic acidification rather than its intracellular antioxidant activity. Instead, oxidative conversion of ascorbic acid into dehydroascorbic acid may inhibit apoptosis through the inhibition of caspases. [ABSTRACT FROM AUTHOR]

Abstract: The oracle identification problem (OIP) was introduced by Ambainis et al. [A. Ambainis, K. Iwama, A. Kawachi, H. Masuda, R.H. Putra, S. Yamashita, Quantum identification of boolean oracles, in: Proc. of STACS’04, in: LNCS, vol. 2996, 2004, pp. 105–116]. It is given as a set of oracles and a blackbox oracle . Our task is to figure out which oracle in is equal to the blackbox by making queries to . OIP includes several problems such as the Grover Search as special cases. In this paper, we improve the algorithms in [A. Ambainis, K. Iwama, A. Kawachi, H. Masuda, R.H. Putra, S. Yamashita, Quantum identification of boolean oracles, in: Proc. of STACS’04, in: LNCS, vol. 2996, 2004, pp. 105–116] by providing a mostly optimal upper bound of query complexity for this problem: (i) For any oracle set such that , we design an algorithm whose query complexity is , matching the lower bound proved in [A. Ambainis, K. Iwama, A. Kawachi, H. Masuda, R.H. Putra, S. Yamashita, Quantum identification of boolean oracles, in: Proc. of STACS’04, in: LNCS, vol. 2996, 2004, pp. 105–116]. (ii) Our algorithm also works for the range between and (where the bound becomes ), but the gap between the upper and lower bounds worsens gradually. (iii) Our algorithm is robust, namely, it exhibits the same performance (up to a constant factor) against noisy oracles as also shown in the literature [M. Adcock, R. Cleve, A quantum Goldreich–Levin theorem with cryptographic applications, in: Proc. of STACS’02, in: LNCS, vol. 2285, 2002, pp. 323–334; H. Buhrman, I. Newman, H. Röhrig, R. deWolf, Robust quantum algorithms and polynomials, in: Proc. of STACS’05, in: LNCS, vol. 3404, 2005, pp. 593–604; P. Høyer, M. Mosca, R. de Wolf, Quantum search on bounded-error inputs, in: Proc. of ICALP’03, in: LNCS, vol. 2719, 2003, pp. 291–299] for special cases of OIP. [Copyright &y& Elsevier]