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We investigated the hydrogenation of the L 1 2 -type AlNi 3 alloy at 3 GPa and 500 °C using in situ synchrotron radiation X-ray diffraction measurements. An isotropic lattice expansion was observed to have occurred owing to the hydrogenation, and a novel hydride (AlNi 3 H x ) was formed. Because of such isotropic lattice expansion, the hydrogen-occupied sites were the body-center sites of the L 1 2 structure ( Pm -3 m ). In this case, the hydrogen content was calculated to be x = 1.0, which is consistent with the experimental results. The AlNi 3 H x hydride was stable under ambient conditions. [ABSTRACT FROM AUTHOR]

Bi(Ni0.5Ti0.5)O3 (BNT) ceramics with a perovskite structure, which were almost impossible to fabricate under atmospheric pressure, were synthesized at a high pressure of 6 GPa using a multianvil-type high-pressure apparatus. It was confirmed that the synthesized samples had a multidomain structure and ferroelectricity on the basis of scanning nonlinear dielectric microscopy (SNDM) and polarization-electric field (P-E) hysteresis loop measurements. [ABSTRACT FROM AUTHOR]

Transition metal-based intermetallic materials are candidates for high-temperature structural applications. However, they are limited by their low fracture toughness at ambient temperature. Given Fe is a low-cost metal with a low environmental impact, it is necessary to design tough Fe-based intermetallic alloys. We report a novel ferrite-Fe 2 Mo intermetallic synthesized through arc melting and quenching of Fe 0.78 Mo 0.22 alloy. Diffusional-displacive mixed-mode transformation of the parent ferrite phase resulted in the formation of nanocomposite microstructure. Two distinct microstructure morphologies of the product μ phase were observed: (i) allotriomorphic phase formation at the parent ferrite grain boundaries and (ii) formation of basket-weave Widmanstätten structures at the parent grain interior. Electron probe microanalysis (EPMA) revealed Mo partitioning across ∼800 nm wide Widmanstätten laths, establishing that it is a diffusional-displacive mixed-mode transformation. We performed atom probe tomography (APT) investigations to ascertain the nanoscale Mo solute partitioning. Based on the chemistry of the retained parent ferrite, the Mo partitioning temperature was estimated to be ∼865 °C. Mo partitioned Widmanstätten lath formation is clarified using a shear-assisted diffusional transformation model. APT studies further revealed that the composition of the product μ phase corresponds to stoichiometric Fe 2 Mo. It is an anomaly since stoichiometric Fe 2 Mo typically corresponds to λ C14 Laves phase. We explain the mechanism of μ phase formation with Fe 2 Mo stoichiometry. The nanocomposite exhibits a high hardness (HV 2) of 7.54 GPa and excellent toughness (evidenced by resistance to indentation cracking). [Display omitted] • Ferrite-Fe 2 Mo intermetallic nanocomposite synthesized via mixed-mode transformation. • Microstructure consists of Mo partitioned Widmanstätten laths (diffusional-displacive). • Nanoscale Mo solute partitioning is characterized by atom probe tomography. • Mixed-mode transformation is explained using a shear-assisted diffusion mechanism. • Exhibited high hardness (7.54 GPa) and exceptional indentation cracking resistance. [ABSTRACT FROM AUTHOR]

Japanese isolates of Bacillus thuringiensis were screened for larvicidal activity against the mosquito Anopheles stephensi, the urban malaria vector of the Indian subcontinent. Among more than 30 strains identified, larvicidal activity causing >80% mortality in 72 h was demonstrated for 41/1449 (2.8%) isolates. The majority of strains and isolates (97.2%) exhibited little or no larvicidal activity. Anopheles-active strains belonged to more than 12 H serotypes, especially H3ade (serovar fukuokaensis) and H44 (serovar higo). SDS-PAGE profiles of inclusion proteins showed 4 distinct types among 6 active strains examined. The most active Japanese isolates were H20 strain 89-T-34-14 (LC50 4.4 μg/ml) and H44 serovar higo strain 74-E-45-24 (LC50 7.6 μg/ml), respectively, 13-fold and 23-fold less active than the international standard H14 serovar israelensis (LC50 0.33 μg/ml). [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis strain A1462 produced two parasporal inclusion proteins with a molecular mass of 88 kDa that were converted to 64-kDa toxins when activated by proteinase K digestion. Both toxins exhibited strong cytocidal activity against two human cancer cell lines, HL60 (myeloid leukemia cells) and HepG2 (liver cancer cells), while low or no toxicities were observed against 11 human and three mammalian cell lines, including four non-cancer cell lines. The cytotoxicity of both toxins on susceptible cells was characterized by rapid cell swelling. Gene cloning experiments provided two novel genes encoding 88-kDa Cry proteins, Cry41Aa and Cry41Ab. The amino acid sequences of the two proteins contain five block regions commonly conserved in B. thuringiensis insecticidal Cry proteins. This is the first report of the occurrence of typical three-domain Cry proteins with cytocidal activity preferential for cancer cells. [ABSTRACT FROM PUBLISHER]

This article presents a Bayesian sparse modeling method to analyze extended x-ray absorption fine structure (EXAFS) data with basis functions built on two-body signals. This method does not require any structural model and allows us to evaluate regression coefficients proportional to the radial distribution functions of the respective elements and their errors and is very effective for analysis of EXAFS with weak absorption intensity and severe signal-to-noise ratios. As an application example, we used it to analyze the EXAFS of an yttrium oxyhydride (YOxHy) epitaxial thin film. These EXAFS data show weak absorption intensity and a severe signal-to-noise ratio due to the small amount of x-ray absorption in the thin film sample. However, this approach revealed that the radial distance ratio of the second neighbor yttrium to the first neighbor oxygen coincides with that of a tetrahedral configuration. This result demonstrates that the interstitial oxygen position is tetrahedral in the YOxHy thin film. [ABSTRACT FROM AUTHOR]

• Hydrogen embrittlement behavior of a stretch-formed TRIP-aided steel was investigated. • Residual stress and plastic strain were analyzed by means of hard synchrotron X-rays. • Crack initiation took place at the region of the foot of the impression. • High tensile stress was detected at the region from the foot to the hillside. • The crack initiation site corresponded to the region where acted the maximum stress. Hydrogen assisted cracking on hemispherically-stretch-formed specimens of transformation induced plasticity-aided martensitic steel was investigated. Hydrogen charging induced cracking around the foot of the impression formed on the steel sheet, and the cracks propagated along the radial direction toward the hillside and the plains. Distributions of stress, plastic strain and volume fraction of retained austenite were analyzed employing the energy-dispersive X-ray diffraction method utilizing the synchrotron X-ray radiation at SPring-8. It was notable that the crack initiation took place in the region where the measured tensile stress was the highest. Influences of plastic strain and resulted martensitic transformation were also suggested. [ABSTRACT FROM AUTHOR]

In the study, the pre-strain effect on hydrogen embrittlement property of the ultra-high-strength transformation-induced plasticity (TRIP)-aided bainitic ferrite (TBF) steel was investigated towards application for automobile frame parts. Specifically, 3–10% tensile pre-strain suppressed hydrogen-induced mechanical degradation relative to total elongation (pre-strain + elongation after hydrogen charging) while 12–15% pre-strained specimen did not exhibit elongation after hydrogen charging. The advantageous effect of the 3–10% pre-strain was attributed to the suppression of crack initiation related to retained austenite. Specifically, the TRIP by pre-straining decreased the volume fraction of retained austenite before hydrogen charging, thereby reducing existing probabilities of preferential crack initiation sites and propagation paths. Conversely, high pre-strain such as 12–15% does not effectively work due to work hardening resulting in increases in hydrogen embrittlement susceptibility and a significant increase in hydrogen content due to the multiplication of dislocations. [ABSTRACT FROM AUTHOR]

The title compound is prepared by hot pressing of a mixture of PbO2 and ZnO together with KClO3 as oxidizing agent (multianvil press, 5-7.5 GPa, 1000-1200 °C, 30 min). [ABSTRACT FROM AUTHOR]

We investigated the hydrogenation of a ternary TiFe 0.8 Mn 0.2 alloy under high pressure (up to 6.5 GPa) and at high temperature (up to 600 °C) by in situ synchrotron radiation X-ray diffraction measurements. A chemical order–disorder phase transition and the formation of body-centered cubic (BCC) hydride were observed. The phase-transition temperature was 400 °C, which is 200 °C lower than that of a binary TiFe alloy. A disproportionation reaction, which was observed for the binary TiFe alloy, did not occur at this temperature. The BCC hydride existed stably, and new hydrides were not formed after the BCC hydride became a single phase. Since the unit cell volume of the BCC hydride was almost equal to that of the γ hydride, TiFe 0.8 Mn 0.2 H 1.8 , under the same pressure–temperature conditions, the hydrogen content of the former was roughly estimated as the same as that of the latter (hydrogen to metal atom ratio = 0.9). [ABSTRACT FROM AUTHOR]

The origins of the superior work hardening capability of medium manganese (M-Mn) and conventional transformation-induced plasticity-aided bainitic ferrite (TBF) steels of similar tensile strength and elongation are comparatively investigated via synchrotron X-ray diffraction measurements. The M-Mn steel undergoes preferential plastic deformation in austenite; its superior work hardening capability and associated uniform elongation are attributed to the high rates of martensitic transformation and dislocation accumulation per strain in the retained austenite. By contrast, the excellent work hardening behavior and uniform elongation of the TBF steel are attributed to the sustained transformability until the occurrence of a large strain and significant stress partitioning between the face-centered cubic (FCC) and body-centered cubic (BCC) phases due to the high austenite phase stability and high resistance to slip deformation of austenite. [Display omitted] [ABSTRACT FROM AUTHOR]

At high temperatures and high pressures, iron reacts with hydrogen to form hydrides. Three hydride phases are present at moderate temperature and pressure ranges below 2000 K and 20 GPa: α, γ, and ε′ phases, respectively, with bcc, fcc, and double-hcp (dhcp) structures. Recent reports have described studies of phase transitions at temperatures and pressures that differ greatly from those predicted from the conventional phase diagram for the Fe–H system established in the early 2000s. We conducted in-situ X-ray diffraction experiments to investigate α/ε′–γ phase boundaries at temperatures up to 900 K and pressures up to 9.1 GPa. Phase transition temperatures were determined by averaging those observed upon heating and cooling under constant pressure. The α/ε′–γ phase boundaries were found at temperatures 150–300 K higher than the conventional phase boundaries. The α–γ–ε′ triple point was expected to relocate accordingly. • In-situ X-ray diffraction experiments were conducted to investigate α/ε'–γ phase boundaries for iron hydride. • The α/ε'–γ phase boundaries for iron hydride were found at 150–300 K higher than the conventional phase boundaries. [ABSTRACT FROM AUTHOR]

While conventional radiation therapy uses white X-rays that consist of a mixture of X-ray waves with various energy levels, a monochromatic X-ray (monoenergetic X-ray) has a single energy level. Irradiation of high-Z elements such as gold, silver or gadolinium with a synchrotron-generated monochromatic X-rays with the energy at or higher than their K-edge energy causes a photoelectric effect that includes release of the Auger electrons that induce DNA damage—leading to cell killing. Delivery of high-Z elements into cancer cells and tumor mass can be facilitated by the use of nanoparticles. Various types of nanoparticles containing high-Z elements have been developed. A recent addition to this growing list of nanoparticles is mesoporous silica-based nanoparticles (MSNs) containing gadolinium (Gd–MSN). The ability of Gd–MSN to inhibit tumor growth was demonstrated by evaluating effects of irradiating tumor spheroids with a precisely tuned monochromatic X-ray. [ABSTRACT FROM AUTHOR]

Superstoichiometric hydrides PdH x have been synthesized by the electrochemical method. The H concentrations, x = H/Pd = 1.13–1.97, have been determined directly by thermal desorption. From X-ray diffraction, the structure is found to be face-centered cubic, with the lattice parameter changing smoothly over the concentration range, x = 0.7–2.0. Surprisingly, however, the lattice parameter goes through a maximum at x ∼1.0 and decreases at higher concentrations. It is suggested from electronic and Monte Carlo calculations that these unique features of the structure and formation process should be the consequence of partial replacement of Pd atoms with H 2 , namely, the formation of superabundant vacancies filled with H 2 molecules. Image 1 • Superstoichiometric hydrides PdH 1.4

Reports on a patient who appeared to have typical acute promyelocytic leukemia, both morphologically and cytogenetically, in whom tretinoin induced a marked increase in basophils and hyperhistaminemia resulting in shock and severe gastric and duodenal ulceration. Case report on a 36-year-old Japanese man; White-cell count; Hemoglob in level; More.

Ninefold coordination of hydrogen is very rare, and has been observed in two different hydride complexes comprising rhenium and technetium. Herein, based on a theoretical/experimental approach, we present evidence for the formation of ninefold H- coordination hydride complexes of molybdenum ([MoH9]3−), tungsten ([WH9]3−), niobium ([NbH9]4−) and tantalum ([TaH9]4−) in novel complex transition-metal hydrides, Li5MoH11, Li5WH11, Li6NbH11 and Li6TaH11, respectively. All of the synthesized materials are insulated with band gaps of approximately 4 eV, but contain a sufficient amount of hydrogen to cause the H 1s-derived states to reach the Fermi level. Such hydrogen-rich materials might be of interest for high-critical-temperature superconductivity if the gaps close under compression. Furthermore, the hydride complexes exhibit significant rotational motions associated with anharmonic librations at room temperature, which are often discussed in relation to the translational diffusion of cations in alkali-metal dodecahydro-closo-dodecaborates and strongly point to the emergence of a fast lithium conduction even at room temperature. [ABSTRACT FROM AUTHOR]

Oxyhydrides with multi-anions (O 2- and H - ) are a recently developed material family and have attracted attention as catalysts and hydride ion conductors. High-pressure and high-temperature reactions are effective in synthesizing oxyhydrides, but the reactions sometimes result in inhomogeneous products due to insufficient diffusion of the solid components. Here, we synthesized new perovskite oxyhydrides SrVO 2.4 H 0.6 and Sr 3 V 2 O 6.2 H 0.8 . We demonstrated that the addition of SrCl 2 flux promotes diffusion during high-pressure and high-temperature reactions, and can be used for selective synthesis of the oxyhydride phases. We conducted in-situ synchrotron X-ray diffraction measurements to reveal the role of this flux and reaction pathways. We also demonstrated the electronic and magnetic properties of the newly synthesized oxyhydrides and that they work as anode materials for Li-ion batteries with excellent reversibility and high-rate characteristics, the first case with an oxyhydride. Our synthesis approach would also be effective in synthesizing various types of multi-component systems.

Hydrogen can be stored in the interstitial sites of the lattices of intermetallic compounds. To date, intermetallic compound LaNi 5 or related LaNi 5 -based alloys are known to be practical hydrogen storage materials owing to their higher volumetric hydrogen densities, making them a compact hydrogen storage method and allowing stable reversible hydrogen absorption and desorption reactions to take place at room temperature below 1.0 MPa. By contrast, gravimetric hydrogen density is required for key improvements (e.g., gravimetric hydrogen density of LaNi 5 : 1.38 mass%). Although hydrogen storage materials have typically been evaluated for their hydrogen storage properties below 10 MPa, reactions between hydrogen and materials can be facilitated above 1 GPa because the chemical potential of hydrogen dramatically increases at a higher pressure. This indicates that high-pressure experiments above 1 GPa could clarify the latent hydrogen absorption reactions below 10 MPa and potentially explore new hydride phases. In this study, we investigated the hydrogen absorption reaction of LaNi 5 above 1 GPa at room temperature to understand their potential hydrogen storage capacities. The high-pressure experiments on LaNi 5 with and without an internal hydrogen source (BH 3 NH 3 ) were performed using a multi-anvil-type high-pressure apparatus, and the reactions were observed using in situ synchrotron radiation X-ray diffraction with an energy dispersive method. The results showed that 2.07 mass% hydrogen was absorbed by LaNi 5 at 6 GPa. Considering the unit cell volume expansion, the estimated hydrogen storage capacity could be 1.5 times higher than that obtained from hydrogen absorption reaction below 1.0 MPa at 303 K. Thus, 33% of the available interstitial sites in LaNi 5 remained unoccupied by hydrogen atoms under conventional conditions. Although the hydrogen-absorbed LaNi 5 H x (x < 9) was maintained below 573 K at 10 GPa, LaNi 5 H x began decomposing into NiH, and the formation of a new phase was observed at 873 K and 10 GPa. The new phase was indexed to a hexagonal or trigonal unit cell with a ≈ 4.44 Å and c ≈ 8.44 Å. Further, the newly-formed phase was speculated to be a new hydride phase because the Bragg peak positions and unit cell parameters were inconsistent with those reported for the La-Ni intermetallic compounds and La-Ni hydride phases.

Internal exposure to actinides such as uranium and plutonium has been reduced using chelating agents for decorporation because of their potential to induce both radiological and chemical toxicities. This study measures uranium chemical forms in serum in the presence and absence of chelating agents based on X-ray absorption spectroscopy (XAS). The chelating agents used were 1-hydroxyethane 1,1-bisphosphonate (EHBP), inositol hexaphosphate (IP6), deferoxamine B (DFO), and diethylenetriaminepentaacetate (DTPA). Percentages of uranium-chelating agents and uranium-bioligands (bioligands: inorganic and organic ligands coordinating with uranium) dissolving in the serum were successfully evaluated based on principal component analysis of XAS spectra. The main ligands forming complexes with uranium in the serum were estimated as follows: IP6 > EHBP > bioligands > DFO ≫ DTPA when the concentration ratio of the chelating agent to uranium was 10. Measurements of uranium chemical forms and their concentrations in the serum would be useful for the appropriate treatment using chelating agents for the decorporation of uranium.

Irradiation of high Z elements such as iodine, gold, gadolinium with monochromatic X-rays causes photoelectric effects that include the release of Auger electrons. Decay of radioactive iodine such as I-123 and I-125 also results in multiple events and some involve the generation of Auger electrons. These electrons have low energy and travel only a short distance but have a strong effect on DNA damage including the generation of double-strand breaks. In this chapter, we focus on iodine and discuss various studies that used iodine-containing chemicals to generate Auger electrons and cause DNA double-strand breaks. First, DNA synthesis precursors containing iodine were used to place iodine on DNA. DNA binding dyes such as iodine Hoechst were investigated for Auger electron generation and DNA breaks. More recently, iodine containing nanoparticles were developed. We describe our study using tumor spheroids loaded with iodine nanoparticles and synchrotron-generated monochromatic X-rays. This study led to the demonstration that an optimum effect on DNA double-strand break formation is observed with a 33.2keV X-ray which is just above the K-edge energy of iodine., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The use of hydrogen in iron and steel has the potential to improve mechanical properties via altering the phase stability and dislocation behavior. When hydrogen is introduced under several gigapascals, a stoichiometric composition of hydrogen can be introduced for steel compositions. In this study, a face-centered cubic (fcc) stainless steel was hydrogenated under several gigapascals. When the steel was not hydrogenated, the microstructure after depressurization was an fcc with a hexagonal close-packed (hcp) structure. In contrast, the hydrogenation treatment resulted in a fine lath body-centered cubic (bcc) structure arising from diffusionless transformation. In particular, the bcc phase formed through the following transformation sequence: fcc → hcp → dhcp (double hexagonal close-packed phase) → bcc. That is, the use of hydrogenation treatment realized fine microstructure evolution through a new type of diffusionless transformation sequence, which is expected to be used in future alloy design strategies for developing high-strength steels., (© 2021. The Author(s).)

X-ray irradiation of high Z elements causes photoelectric effects that include the release of Auger electrons that can induce localized DNA breaks. We have previously established a tumor spheroid-based assay that used gadolinium containing mesoporous silica nanoparticles and synchrotron-generated monochromatic X-rays. In this work, we focused on iodine and synthesized iodine-containing porous organosilica (IPO) nanoparticles. IPO were loaded onto tumor spheroids and the spheroids were irradiated with 33.2 keV monochromatic X-ray. After incubation in CO 2 incubator, destruction of tumor spheroids was observed which was accompanied by apoptosis induction, as determined by the TUNEL assay. By employing the γH2AX assay, we detected double strand DNA cleavages immediately after the irradiation. These results suggest that IPO first generate double strand DNA breaks upon X-ray irradiation followed by apoptosis induction of cancer cells. Use of three different monochromatic X-rays having energy levels of 33.0, 33.2 and 33.4 keV as well as X-rays with 0.1 keV energy intervals showed that the optimum effect of all three events (spheroid destruction, apoptosis induction and generation of double strand DNA breaks) occurred with a 33.2 keV monochromatic X-ray. These results uncover the preferential effect of K-edge energy X-ray for tumor spheroid destruction mediated by iodine containing nanoparticles., (© 2021. The Author(s).)

Neutron powder diffraction profiles were collected for iron deuteride (FeD x ) while the temperature decreased from 1023 to 300 K for a pressure range of 4-6 gigapascal (GPa). The ε' deuteride with a double hexagonal close-packed (dhcp) structure, which coexisted with other stable or metastable deutrides at each temperature and pressure condition, formed solid solutions with a composition of FeD 0.68(1) at 673 K and 6.1 GPa and FeD 0.74(1) at 603 K and 4.8 GPa. Upon stepwise cooling to 300 K, the D-content x increased to a stoichiometric value of 1.0 to form monodeuteride FeD 1.0 . In the dhcp FeD 1.0 at 300 K and 4.2 GPa, dissolved D atoms fully occupied the octahedral interstitial sites, slightly displaced from the octahedral centers in the dhcp metal lattice, and the dhcp sequence of close-packed Fe planes contained hcp-stacking faults at 12%. Magnetic moments with 2.11 ± 0.06 μ B /Fe-atom aligned ferromagnetically in parallel on the Fe planes.

A SnI 4 molecule lowers its symmetry from T d to [Formula: see text] on the liquid-liquid transition. Because it is possible to lower the molecular symmetry without violating the crystalline symmetry, it is worth examining whether the deformation occurs in the crystalline phase field. Extended x-ray absorption fine structure (EXAFS) measurements on the crystalline state were carried out to investigate the change in the environment around a Sn atom at high pressures and temperatures. We could not find clear evidence on the symmetry change of molecules even close to the melting points, where the melting curve becomes abnormally flat against pressure. Indeed, no inconsistency was found when we assumed that the coordination number of a Sn atom remains unchanged in the temperature and pressure range examined. The situation remains true when the system entered the high-pressure crystalline phase on compression. We can propose a consistent scenario as to the structural change on the phase transformation. The incompressibility of a SnI 4 molecule could be suitably quantified. The procedure enabled us to conclude the molecule is more than an order of magnitude incompressible than the lattice.

Synchrotron generated monochromatic X-rays can be precisely tuned to the K-shell energy of high Z materials resulting in the release of the Auger electrons. In this work, we have employed this mechanism to destruct tumor spheroids. We first loaded gadolinium onto the surface of mesoporous silica nanoparticles (MSNs) producing gadolinium-loaded MSN (Gd-MSN). When Gd-MSN was added to the tumor spheroids, we observed efficient uptake and uniform distribution of Gd-MSN. Gd-MSN also can be taken up into cancer cells and localize to a site just outside of the cell nucleus. Exposure of the Gd-MSN containing tumor spheroids to monochromatic X-ray beams resulted in almost complete destruction. Importantly, this effect was observed at an energy level of 50.25 keV, but not with 50.0 keV. These results suggest that it is possible to use precisely tuned monochromatic X-rays to destruct tumor mass loaded with high Z materials, while sparing other cells. Our experiments point to the importance of nanoparticles to facilitate loading of gadolinium to tumor spheroids and to localize at a site close to the nucleus. Because the nanoparticles can target to tumor, our study opens up the possibility of developing a new type of radiation therapy for cancer.

Hexagonal close-packed iron hydride, hcp FeH x , is absent from the conventional phase diagram of the Fe-H system, although hcp metallic Fe exists stably over extensive temperature (T) and pressure (P) conditions, including those corresponding to the Earth's inner core. In situ X-ray and neutron diffraction measurements at temperatures ranging from 298 to 1073 K and H pressures ranging from 4 to 7 GPa revealed that the hcp hydride was formed for FeH x compositions when x < 0.6. Hydrogen atoms occupied the octahedral interstitial sites of the host metal lattice both partially and randomly. The hcp hydride exhibited a H-induced volume expansion of 2.48(5) Å 3 /H-atom, which was larger than that of the face-centered cubic (fcc) hydride. The hcp hydride showed an increase in x with T, whereas the fcc hydride showed a corresponding decrease. The present study provides guidance for further investigations of the Fe-H system over an extensive x-T-P region.

The similarity in the shape of the melting curve of GeI 4 to that of SnI 4 suggests that a liquid-liquid transition as observed in liquid SnI 4 is also expected to occur in liquid GeI 4 . Because the slope of the melting curve of GeI 4 abruptly changes at around 3 GPa, in situ synchrotron diffraction measurements were conducted to examine closely the structural changes upon compression at around 3 GPa. The reduced radial distribution functions of the high- and low-pressure liquid states of GeI 4 share the same feature inherent in the high-pressure (high-density) and low-pressure (low-density) radial distribution functions of liquid SnI 4 . This feature allows us to introduce local order parameters that we may use to observe the transition. Unlike the transition in liquid SnI 4 , the transition from the low-pressure to the high-pressure structure seems sluggish. We speculate that the liquid-liquid critical point of GeI 4 is no longer a thermodynamically stable state and is slightly located below the melting curve. As a result, the structural change is said to be a crossover rather than a transition. The behavior of the local-order parameters implies a metastable extension of the liquid-liquid phase boundary with a negative slope.

A novel LiNbO3-type (LN-type) lead zinc oxide, PbZnO3, was successfully synthesized under high pressure and temperature. Rietveld structure refinement using synchrotron powder X-ray diffraction (XRD) data demonstrated that LN-type PbZnO3 crystallized into a trigonal structure with a polar space group (R3c). The bond valence sum estimated from the interatomic distances indicated that the sample possesses a Pb(4+)Zn(2+)O3 valence state. Polarization could evolve as a result of the repulsion between constituent cations because PbZnO3 does not contain a stereochemical 6s(2) cation or a Jahn-Teller active d(0) cation. Distortion of ZnO6 octahedra resulting from cation shift is comparable with that of d(0) TiO6 in ZnTiO3 and MnTiO3 with LN-type oxides, which leads to stabilization of the polar structure. PbZnO3 exhibited metallic behavior and temperature-independent diamagnetic character. In situ XRD measurement revealed that the formation of LN-type PbZnO3 occurred directly without the formation of a perovskite phase, which is unusual among LN-type materials obtained by high-pressure synthesis.

Despite many exploratory studies over the past several decades, the presently known transition metals that form homoleptic transition-metal hydride complexes are limited to the Groups 7-12. Here we present evidence for the formation of Mg3 CrH8 , containing the first Group 6 hydride complex [CrH7 ](5-) . Our theoretical calculations reveal that pentagonal-bipyramidal H coordination allows the formation of σ-bonds between H and Cr. The results are strongly supported by neutron diffraction and IR spectroscopic measurements. Given that the Group 3-5 elements favor ionic/metallic bonding with H, along with the current results, the true boundary for the formation of homoleptic transition-metal hydride complexes should be between Group 5 and 6. As the H coordination number generally tends to increase with decreasing atomic number of transition metals, the revised boundary suggests high potential for further discovery of hydrogen-rich materials that are of both technological and fundamental interest., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Parasporin is the cytocidal protein present in the parasporal inclusion of the non-insecticidal Bacillus thuringiensis strains, which has no hemolytic activity but has cytocidal activities, preferentially killing cancer cells. In this study, we characterized a cytocidal protein that belongs to this category, which was designated parasporin-5 (PS5). PS5 was purified from B. thuringiensis serovar tohokuensis strain A1100 based on its cytocidal activity against human leukemic T cells (MOLT-4). The 50% effective concentration (EC₅₀) of PS5 to MOLT-4 cells was approximately 0.075 μg/mL. PS5 was expressed as a 33.8-kDa inactive precursor protein and exhibited cytocidal activity only when degraded by protease at the C-terminal into smaller molecules of 29.8 kDa. Although PS5 showed no significant homology with other known parasporins, a Position Specific Iterative-Basic Local Alignment Search Tool (PSI-BLAST) search revealed that the protein showed slight homology to, not only some B. thuringiensis Cry toxins, but also to aerolysin-type β-pore-forming toxins (β-PFTs). The recombinant PS5 protein could be obtained as an active protein only when it was expressed in a precursor followed by processing with proteinase K. The cytotoxic activities of the protein against various mammalian cell lines were evaluated. PS5 showed strong cytocidal activity to seven of 18 mammalian cell lines tested, and low to no cytotoxicity to the others.

Bacillus thuringiensis A1470 produces multiple proteins with similar molecular masses (~30 kDa) with cytotoxicity against human cell lines. One that was previously identified, parasporin-4, is a β-pore-forming toxin. The N-terminal sequence of a second cytotoxic protein was identical to a partial sequence of parasporin-2 produced by B. thuringiensis A1547. PCR was performed on total plasmid DNA from A1470 by using primers for parasporin-2 to amplify a gene which was then cloned. The cloned gene differed from A1547 parasporin-2 by 8 bp and the predicted protein differed by four amino acids. The gene was expressed in Escherichia coli, and the cytotoxic activities of the recombinant protein against four human cell lines (MOLT-4, Jurkat, HeLa, and HepG2) were similar to those of A1547 parasporin-2. We then confirmed that the A1470 strain simultaneously produces parasporin-2 and parasporin-4.

The effects of temperature and pressure upon structural, dynamical, and electronic properties of liquid H(2)O were systematically investigated via first principles molecular dynamics and in situ x-ray diffraction in the chosen isochore (1.00-1.61 g/cm(3)) and isotherm (300-900 K) conditions. Our study suggests that the crossover occurs between H-bonded and simple-liquidlike liquids by raising temperature in molecular liquid phase.

In 1901, a unique bacterium was isolated as a pathogen of the sotto disease of the silkmoth larvae, and later in 1915, the organism was described as Bacillus thuringiensis. Since the discovery, this bacterium has widely attracted attention of not only insect pathologists but many other scientists who are interested in strong and specific insecticidal activity associated with inclusion bodies of B. thuringiensis. This has led to the recent worldwide development of B. thuringiensis-based microbial insecticides and insect-resistant transgenic plants, as well as the epoch-making discovery of parasporin, a cancer cell-specific cytotoxin. In the review, we introduce a detection study of interaction between inclusion proteins of B. thuringiensis and brush border membrane of insects using surface plasmon resonance-based biosensor, and then identification and cloning of parasporin-4, a latest cancer cell-killing protein produced by B. thuringiensis A1470 strain. Inclusion bodies of the parasporin-4 produced by recombinant Escherichia coli were solubilized and activated with a new method and purified by an anion-exchange chromatography. At last the characterization of the recombinant parasporin-4 was shown.

A novel delta-endotoxin gene from a lepidopteran-specific Bacillus thuringiensis serovar galleriae strain was cloned, and the full sequence of the cry gene was determined. The cloned 6.5-kb DNA fragment included the full sequence of the cry gene and three open reading frames located upstream of the cry gene. The gene, designated cry9Ec1, encodes a polypeptide of 1154 amino acid residues with a predicted molecular weight of 130 237. The deduced amino acid sequence of the Cry9Ec1 protein had the highest homology (77.7%) with the Cry9Ea1 protein when compared with existing Cry proteins. The expression, in an acrystalliferous B. thuringiensis strain, of the cry9Ec1 gene was high when controlled by the cyt1A2 promoter, leading to the formation of large spherical inclusions. The purified crystals from the recombinant strain were toxic when tested against two lepidopteran species, Bombyx mori and Plutella xylostella. However, the Cry9Ec1 protein gave no toxicity against Spodoptera litura, Spodoptera exigua, Plodia interpunctella, Helicoverpa zea, and Culex pipiens molestus.

Two new crystal protein genes, cry24B and s1orf2, were cloned from a mosquitocidal Bacillus thuringiensis serovar sotto strain. The cry24B and s1orf2 genes encoded a 76-kDa and 62-kDa protein, respectively. The Cry24B protein retained five conserved regions commonly found in the existing Cry proteins. The amino acid sequence of the S1ORF2 had a high homology to that of the ORF2 protein of B. thuringiensis serovar jegathesan. Southern hybridization experiments with a cry24B gene-specific probe revealed that these genes are located on two large plasmids of > 100 kb. When the two genes, cry24B and s1orf2, were expressed in an acrystalliferous B. thuringiensis host, the proteins were synthesized and accumulated as inclusions. These inclusions exhibited no larvicidal activities against three mosquito species: Aedes aegypti, Anopheles stephensi, and Culex pipiens molestus. Likewise, the inclusions contained no cytocidal activity against HeLa cells.

A new insertion variant belonging to the family IS231, designated IS231I, was isolated from a mosquito larvicidal strain of the Bacillus thuringiensis serovar sotto (H4ab). IS231I was 1653 bp long and delimited by two 20 bp inverted repeats with one mismatch, flanked by two perfect 11 bp direct repeats. The element contained a single open reading frame (ORF) encoding 478 amino acids and five conserved domains: N1, N2, N3, C1, and C2. The 5' noncoding region upstream of the ORF, presumed to form a stable stem-and-loop structure, was highly conserved in IS231I. The secondary structure conformation had a deduced free energy (DeltaG=25 degrees C) of -17.2 kcal/mol. Comparison of the IS231I amino acid sequence with those of the 10 existing IS variants revealed that the new variant shares 89% identity with IS231A and IS231B, 65-66% with IS231M and IS231N, and 38% with IS231W.

Two genes encoding the 32- and 40-kDa polypeptides of Bacillus thuringiensis strain 90-F-45-14 crystals were cloned, expressed in an acrystalliferous B. thuringiensis strain, and sequenced. The polypeptides had deduced molecular weights of 30,319 and 33,885, respectively. The amino acid sequence of the 32-kDa protein was 37.7% identical to the known sequence of a non-insecticidal parasporal protein in B. thuringiensis serovar thompsoni crystals. The sequence of the cloned 40-kDa protein was 37.0% and 22.3% identical to that of the existing Cry protein classes, Cry15Aa1 and Cry23Aa1, respectively. Thus, this protein constitutes a novel protein class, Cry33Aa1. The open reading frames of the two genes were located on the predominant plasmid of 17,629 bp (=11,752 MDa) in the same orientation, and they were separated by the sequence of 32 nucleotides. The two proteins are likely produced simultaneously from a single transcript to form spherical crystals.