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For more than half a century, exploring a complete sequence of the oceanic crust from the seafloor through the Mohorovičić discontinuity (Moho) and into the uppermost mantle has been one of the most challenging missions of scientific ocean drilling. Such a scientific and technological achievement would provide humankind with profound insights into the largest realm of our planet and expand our fundamental understanding of Earth's deep interior and its geodynamic behavior. The formation of new oceanic crust at mid-ocean ridges and its subsequent aging over millions of years, leading to subduction, arc volcanism, and recycling of some components into the mantle, comprise the dominant geological cycle of matter and energy on Earth. Although previous scientific ocean drilling has cored some drill holes into old (> 110 Ma) and young (< 20 Ma) ocean crust, our sampling remains relatively shallow (< 2 km into intact crust) and unrepresentative of average oceanic crust. To date, no hole penetrates more than 100 m into intact average-aged oceanic crust that records the long-term history of seawater–basalt exchange (60 to 90 Myr). In addition, the nature, extent, and evolution of the deep subseafloor biosphere within oceanic crust remains poorly unknown. To address these fundamentally significant scientific issues, an international workshop “Exploring Deep Oceanic Crust off Hawai`i” brought together 106 scientists and engineers from 16 countries that represented the entire spectrum of disciplines, including petrologists, geophysicists, geochemists, microbiologists, geodynamic modelers, and drilling/logging engineers. The aim of the workshop was to develop a full International Ocean Discovery Program (IODP) proposal to drill a 2.5 km deep hole into oceanic crust on the North Arch off Hawai`i with the drilling research vessel Chikyu. This drill hole would provide samples down to cumulate gabbros of mature (∼ 80 Ma) oceanic crust formed at a half spreading rate of ∼ 3.5 cm a−1. A Moho reflection has been observed at ∼ 5.5 km below the seafloor at this site, and the workshop concluded that the proposed 2.5 km deep scientific drilling on the North Arch off Hawai`i would provide an essential “pilot hole” to inform the design of future mantle drilling.

The architecture, formation, and modification of oceanic plates are fundamental to our understanding of key geologic processes of the Earth. Geophysical surveys were conducted around a site near the Hawaiian Islands (northeastern Hawaiian North Arch region; Hawaiian North Arch hereafter), which is one of three potential sites for an International Ocean Discovery Program mantle drilling proposal for the Pacific plate that was submitted in 2012. The Hawaiian North Arch site is located in 78–81 Ma Cretaceous crust, which had an estimated full spreading rate of 7–8 cm yr−1. This site fills a major gap in our understanding of oceanic crust. Previously drilling has been skewed to young or older crust ( or >110 Ma) and slow-spread crust. P-wave velocity structure in the uppermost mantle of the Hawaiian North Arch shows a strong azimuthal anisotropy, whereas Moho reflections below the basement are variable: strong and continuous, weak, diffuse, or unclear. We assume that the strength of the Moho reflection is related to the aging of the oceanic plate. The Hawaiian volcanic chain (200 km to the southwest of the proposed drill site) and the nearby North Arch magmatism on the proposed Hawaiian North Arch sites might also have affected recognition of the Moho via deformation and/or magma intrusion into the lower crust of the uppermost mantle. This workshop report describes scientific targets for 2 km deep-ocean drilling in the Hawaiian North Arch region in order to provide information about the lower crust from unrecovered age and spreading rate gaps from previous ocean drillings. Other scientific objectives to be achieved by drilling cores before reaching the target depth of the project are also described in this report.

A key component of subduction initiation rock suites is boninite, a high-magnesium andesite that is uniquely predominant in western Pacific forearc terranes and in select Tethyan ophiolites such as Oman and Troodos. We report, for the first time, the discovery of low-calcium, high-silica boninite in the middle Eocene Zambales ophiolite (Luzon Island, Philippines). Olivine–orthopyroxene microphyric high-silica boninite, olivine–clinopyroxene–phyric low-silica boninite and boninitic basalt occur as lapilli fall deposits and pillow lava flows in the upper volcanic unit of the juvenile arc section (Barlo locality, Acoje Block) of the Zambales ophiolite. This upper volcanic unit overlies a lower volcanic unit consisting of basaltic andesite, andesite to dacitic lavas and explosive eruptive material (subaqueous pahoehoe and lobate sheet flows, agglutinate and spatter deposits) forming a low-silica boninite series. The overall volcanic stratigraphy of the extrusive sequence at Barlo resembles holes U1439 and U1442 drilled by IODP Expedition 352 in the Izu–Ogasawara (Bonin) trench slope. The presence of depleted proto-arc basalts in the Coto Block (45 Ma) (Geary et al., 1989), boninite and boninite series volcanics in Barlo (Acoje Block (44 Ma)) and simultaneous and post-boninite moderate-Fe arc tholeiites in Sual and Subic areas of the Acoje Block (44–43 Ma) indicate that the observed subduction initiation stratigraphy in the Izu–Ogasawara–Mariana forearc is also present in the Zambales ophiolite. Paleolatitudes derived from tilt-corrected sites in the Acoje Block place the juvenile arc of northern Zambales ophiolite in the western margin of the Philippine Sea plate. In this scenario, the origin of Philippine Sea plate boninites (IBM and Zambales) would be in a doubly vergent subduction initiation setting.

No abstract available. doi:10.2204/iodp.sd.10.07.2010

The Integrated Ocean Drilling Program’s (IODP) Expeditions 309 and 312 successfully completed the first sampling of an intact section of upper oceanic crust, through lavas and the sheeted dikes into the uppermost gabbros. Hole 1256D, which was initiated on the Ocean Drilling Program’s (ODP) Leg 206, now penetrates to > 1500 mbsf and > 1250 m sub-basement. The first gabbroic rocks were encountered at 1407 mbsf. Below this, the hole penetrates ~100 m into a complex zone of fractionated gabbros intruded into contact metamorphosed dikes. doi:10.2204/iodp.sd.4.01.2007

Background: 21-hydroxylase deficiency (21-OHD) is caused due to CYP21A2 gene variant. In males, the excess androgens produce varying degrees of penile enlargement and small testes. CHARGE syndrome (CS) has a broad spectrum of symptoms. In males, genital features such as micropenis and cryptorchidism are found in 48% of CS. There are no reports of patients with combined 21-OHD and CS; therefore, it is unknown whether the external genitalia shows penile enlargement or micropenis with/without cryptorchidism., Case: A boy, born at 37 weeks and 5 days of gestational age with no consanguineous marriage, was admitted to our hospital due to congenital cleft lip, cleft palate, micropenis, cryptorchidism, and a ventricular septal defect. He had severe hyponatremia and hyperkalemia on day 10. He was diagnosed to have 21-OHD and CS. His external genitalia demonstrated both cryptorchidism and micropenis, but not penile enlargement., Methods: DNA was extracted from peripheral leukocytes using standard procedures. Sanger sequence was performed in CYP21A2. Exome sequence was performed, and then, Sanger sequence was performed around variant in CHD7., Results: Genetic screening for CYP21A2 gene was performed and compound heterozygous variants of c.293-13A/C>G (IVS2-13A/C>G) and c.518T>A (p.I172N) were detected in chromosome 6p21.3. His mother had been heterozygous variant of c.293-13A/C>G, and his father had been heterozygous variant of c.518T>A. Simultaneously, a de novo splicing acceptor alteration in c.7165-4 A>G, in chromodomain helicase DNA binding protein-7 (CHD7), located in chromosome 8q12 was detected, and the patient was diagnosed with 21-OHD and CS., Conclusion: Although these two disorders exhibit different modes of inheritance and their co-morbidity is extremely rare, we encountered one male patient who suffered from both 21-OHD and CS., (© 2019 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.)

Hydrolysis of adenosine triphosphate (ATP) is the "energy source" for a variety of biochemical processes. In the present work, we address key features of ATP hydrolysis: the relatively moderate value (about -10 kcal/mol) of the standard free energy, ΔG hyd , of reaction and the insensitivity of ΔG hyd to the number of excess electrons on ATP. We conducted quantum mechanical/molecular mechanical simulation combined with the energy-representation theory of solutions to analyze the electronic-state and solvation contributions to ΔG hyd . It was revealed that the electronic-state contribution in ΔG hyd is largely negative (favorable) upon hydrolysis, due to the reduction of electrostatic repulsion accompanying the breakage of the P-O bond. In contrast, the solvation effect was found to be strongly more favorable on the reactant side. Thus, we showed that a drastic compensation of the two opposite effects takes place, leading to the modest value of ΔG hyd at each number of excess electrons examined. The computational analyses were also conducted for pyrophosphate ions (PPi), and the parallelism between the ATP and PPi hydrolyses was confirmed. Classical molecular dynamics simulation was further carried out to discuss the effect of the solvent environment; the insensitivity of ΔG hyd to the number of excess electrons was seen to hold in solvent water and ethanol.

In a recent work, we developed a method [H. Takahashi et al., J. Chem. Phys. 143, 084104 (2015)] referred to as exchange-core function (ECF) approach, to compute exchange repulsion Eex between solute and solvent in the framework of the quantum mechanical (QM)/molecular mechanical (MM) method. The ECF, represented with a Slater function, plays an essential role in determining Eex on the basis of the overlap model. In the work of Takahashi et al. [J. Chem. Phys. 143, 084104 (2015)], it was demonstrated that our approach is successful in computing the hydrogen bond energies of minimal QM/MM systems including a cationic QM solute. We provide in this paper the extension of the ECF approach to the free energy calculation in condensed phase QM/MM systems by combining the ECF and the QM/MM-ER approach [H. Takahashi et al., J. Chem. Phys. 121, 3989 (2004)]. By virtue of the theory of solutions in energy representation, the free energy contribution δμex from the exchange repulsion was naturally formulated. We found that the ECF approach in combination with QM/MM-ER gives a substantial improvement on the calculation of the hydration free energy of a hydronium ion. This can be attributed to the fact that the ECF reasonably realizes the contraction of the electron density of the cation due to the deficit of an electron.

We developed a simple method to calculate exchange repulsion between a quantum mechanical (QM) solute and a molecular mechanical (MM) molecule in the QM/MM approach. In our method, the size parameter in the Buckingham type potential for the QM solute is directly determined in terms of the one-electron wave functions of the solute. The point of the method lies in the introduction of the exchange core function (ECF) defined as a Slater function which mimics the behavior of the exterior electron density at the QM/MM boundary region. In the present paper, the ECF was constructed in terms of the Becke-Roussel (BR) exchange hole function. It was demonstrated that the ECF yielded by the BR procedure can faithfully reproduce the radial behavior of the electron density of a QM solute. The size parameter of the solute as well as the exchange repulsion are, then, obtained using the overlap model without any fitting procedure. To examine the efficiency of the method, it was applied to calculation of the exchange repulsions for minimal QM/MM systems, hydrogen-bonded water dimer, and H3O(+)-H2O. We found that our approach is able to reproduce the potential energy curves for these systems showing reasonable agreements with those given by accurate full quantum chemical calculations.

Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.

To statistically evaluate the factors that influenced masticatory performance following Maxillectomy, masticatory performance was measured in 43 patients with a post-operative prosthesis by means of a spectrophotometer using adenosine triphosphate (ATP) granules. Our statistical analysis revealed that the number of occluding post-canine teeth and the patient's sex were factors that influenced masticatory performance and demonstrated that it was most important to improve occlusion in the pre-molar/molar region.

To statistically evaluate the factors that influenced speech following maxillectomy, the speech intelligibility (SI) in 54 patients was measured with and without a prosthesis. The mean SI score without a prosthesis in all patients was 35.7 +/- 22.7% and that with a prosthesis was 84.9 +/- 12.7%. The results of the postmaxillectomy SI statistical analysis revealed that an oro-nasal communication was one of the factors that influenced SI without a prosthesis. The resection of the anterior portion of the soft palate was one of the factors that influenced SI with a prosthesis, which suggested that for some of these patients we should consider specific surgical treatment, aimed at the reconstruction in the deep defect extending to the intratemporal fossa. A new classification of maxillary defects has been proposed which will help to predict the grade of post-maxillectomy speech disorder following surgery.

Selective transcatheter arterial embolization, using Gelfoam, was performed in 2 patients with bleeding from tongue arteries due to carcinoma. Though the patients were in poor general condition, being in the terminal stage of cancer, there were no complications and the bleeding was successfully controlled. This method was effective in controlling haemorrhage from the tongue due to carcinoma of the tongue.