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Major and trace element and Nd–Hf isotopic compositions of Paleoproterozoic meta‐igneous rocks from the lower part of the Lesser Himalayan sequence provide insights into the nature of their source mantle and its tectonic setting. We observed bimodal (basaltic and rhyolitic) magmatic compositions in these rocks; this type of volcanism generally occurs in areas of extensional tectonics, particularly rifts. Two types of mafic rocks are identified: within‐plate type (subduction‐unrelated, enriched mantle derived) rocks and Nb–Ta‐depleted, continental arc‐like rocks. Within‐plate type mafic rocks are dominant in the eastern Nepal, though similar rocks are also found in western Nepal. Although models for the tectonic setting of these igneous rocks remain controversial (e.g. passive margin, continental arc, continental rift with possible hotspot), our new geochemical data support the rift model associated with mantle plume activity, which evolved to a passive margin. The Nb–Ta‐depleted, arc‐like rocks have lower εNd (t) (−1.7 to 1.7) and εHf (t) (0.9–4.4) than within‐plate type rocks; we consider that these rocks are formed from the interaction of mantle‐derived magmas with crustal components. All felsic rocks have similar or slightly lower εNd (t) (−5.2 to −0.1) and εHf (t) (−6.5 to 2.7) values relative to arc‐like mafic rocks, suggesting relatively limited crustal interaction. They may be derived from juvenile crust of underplated mafic magmas. Most of the felsic rocks have remarkably low Nb/Ta ratios (< 5), suggesting modification on their chemical composition by intensive sub‐solidus magmatic‐hydrothermal alteration. [ABSTRACT FROM AUTHOR]

Abstract A set of 72 low-volume seawater samples (25 mL) collected from 9 stations in the East China Sea in 2009 and 2011 is analyzed for dissolved rare earth element (REE) concentrations. The elemental concentrations in continental shelf waters are markedly higher than those from the shelf slope and Okinawa Trough waters. The transition in the REE concentrations of seawater between the slope and trough is relatively smooth. In the continental shelf, the influences of fluvial input, e.g., from Changjiang River and Yellow River water, and particle scavenging processes on shelf water are significant. The further northern seawater mass in the Okinawa Trough is likely to be more influenced by fluvial input and coastal water masses from the southern Kyushu at the surface then to interact with deep Kuroshio Current water. The Kuroshio Current, along with the vertical geochemical processes, mainly governs the water in the Okinawa Trough. The North Pacific Deep Water (NPDW)-normalized REE patterns of surface and tropical seawaters from the Okinawa Trough, however, exhibit spatial variation from south to north. The intermediate water of the Okinawa Trough is significantly governed by scavenging processes and REE released from lateral transport from the slope along with the movement of the Kuroshio Current. Some sites are also influenced by hydrothermal venting. The interactions between the Kuroshio Current and shelf water masses are also observed, with pronounced evidence of a "turbidity tongue" intrusion from the shelf to the Kuroshio Current and upwelling of the Kuroshio Current to shelf water. Highlights • There is distinct spatial variation of dissolved REEs in the East China Sea. • The shelf waters are characterized by MREEs enrichments. • The REE distribution demonstrates intrusion of East China Shelf seawater into the Kuroshio Current. • The REE patterns in the Kuroshio Current surface and tropical water are different from those in intermediate depth water. [ABSTRACT FROM AUTHOR]

Late Precambrian–Early Paleozoic igneous rocks constitute volumetrically minor components of the Iranian Plateau but preserve important information about the magmatic and tectonic history of the northern Gondwana margin. The Chadormalu intrusions are part of Central Iran, which includes Late Precambrian–Early Paleozoic continental crust that is now embedded in the Alpine-Himalayan orogenic system. New zircon U-Pb and Sr-Nd-Pb isotope data and whole-rock geochemical analyses are presented on gabbroic to granitic rocks of the Chadormalu district to constrain the magmatic history of the Cadomian orogeny in a disrupted fragment of the northern Gondwana margin. The geochemical data identify I-type calc-alkaline magmatism with typical continental-arc features. The laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb zircon ages range from 531.1 ± 1.6 Ma to 539.8 ± 2.2 Ma, consistent with previous data on the Cadomian basement of Central Iran, and document Early Cambrian subduction and extension along northern Gondwana. Whole rock Sr-Nd isotope data for gabbro (ɛNdi= 0.4; i stands for initial; t = 533 Ma) and granites (ɛNdi= -3.6 to -3.0; t = 531–539 Ma) along with radiogenic Pb isotope data attest to melting of older continental crust triggered by mantle melts. The subduction regime was followed by slab retreat ± delamination in an extensional environment which allowed Ediacaran-early Cambrian flare up of magmatism along the northern Gondwana margin at a regional scale. [ABSTRACT FROM AUTHOR]

This paper provides an assessment of hydrological research activity conducted in the Oceania Region. Literature from three databases (Web of Science (WOS), Scopus, and Google Scholar) was collected and analysed. Results show large gaps in the variety of themes and poor collaborative efforts between regional water specialists. Results also suggest that local specialists potentially lack the ability to conduct quality hydrological research or that, due to the region's developing status, more focus has been placed on project-based objectives rather than building a body of research. A solution could be the development of a self-reliant base for conducting hydrological research by empowering and improving capabilities of local citizens. Firstly, an overhaul of organization policies regarding the introduction of research and performance monitoring is needed. Secondly, education in hydrology must be improved to suit local capabilities while addressing the complex socio-cultural environment with transdisciplinary measures. This assessment could benefit the future management of hydrological services. [ABSTRACT FROM AUTHOR]

The Malayer-Boroujerd plutonic complex (MBPC) in western Iran, consists of a portion of a magmatic arc built by the northeast verging subduction of the Neo-Tethys plate beneath the Central Iranian Microcontinent (CIMC). Middle Jurassic-aged felsic magmatic activity in MBPC is manifested by I-type and S-type granites. The mafic rocks include gabbroic intrusions and dykes and intermediate rocks are dioritic dykes and minor intrusions, as well as mafic microgranular enclaves (MMEs). MBPC Jurassic-aged rocks exhibit arc-like geochemical signatures, as they are LILE- and LREE-enriched and HFSE- and HREE-depleted and display negative Nb-Ta anomalies. The gabbro dykes and intrusions originated from metasomatically enriched garnet-spinel lherzolite [Degree of melting (fmel) ~ 15%] and exhibit negative Nd and positive to slightly negative εHf(T) (+ 3.0 to − 1.6). The data reveal that evolution of Middle Jurassic magmatism occurred in two stages: (1) deep mantle-crust interplay zone and (2) the shallow level upper crustal magma chamber. The geochemical and isotopic data, as well as trace element modeling, indicate the parent magma for the MBPC S-type granites are products of upper crustal greywacke (fmel: 0.2), while I-type granites formed by partial melting of amphibolitic lower crust (fmel: 0.25) and mixing with upper crustal greywacke melt in a shallow level magma chamber [Degree of mixing (fmix): 0.3]. Mixing between andesitic melt leaving behind a refractory dense cumulates during partial crystallization of mantle-derived magma and lower crustal partial melt most likely produced MMEs (fmix: 0.2). However, enriched and moderately variable εNd(T) (− 3.21 to − 4.33) and high (87Sr/86Sr)i (0.7085-0.7092) in dioritic intrusions indicate that these magmas are likely experienced assimilation of upper crustal materials. The interpretations of magmatic activity in the MBPC is consistent with the role considered for mantle-derived magma as heat and mass supplier for initiation and evolution of magmatism in continental arc setting, elsewhere. [ABSTRACT FROM AUTHOR]

Wallerian degeneration is a fundamental process of axonal degeneration distal to the injury site. Although axonal degeneration itself is accomplished in a few days, the subsequent process of removing debris, including myelin debris, in the central nervous system takes more time. Since this debris is a potent inhibitor of axonal regeneration, the removal process is critical for functional recovery after neuronal injuries. Although it is known that microglia/macrophages are involved in this process, the underlying mechanisms are not fully understood. Here, we found that keratan sulfate (KS) expression was induced far from the injury site after spinal cord injury. A hemilateral section of the spinal cord at the third cervical level induced KS expression in a restricted area of the ipsilateral column at the first lumbar level 1 week after injury. This localized KS expression lasted for at least 1 month after injury. The KS signal was merged with a portion of Iba1-positive cells, suggesting that a subpopulation of microglia/macrophages expressed KS. KS-positive cells expressed CD68 and CD86, but not CD206 or arginase 1, suggesting that these microglia/macrophages were in an activated state probably polarized to M1. Our study has explored for the first time the relation between KS expression and activation of microglia/macrophages in Wallerian degeneration. [ABSTRACT FROM AUTHOR]

Abstract: Background: Arundic acid (ONO-2506) inhibits the production and release of S100 protein from astrocytes. While numerous studies have assessed the effect of ONO-2506 in the diseased brain, to the best of our knowledge, no study has examined the effect of ONO-2506 in spinal cord injury (SCI). In this study, we administered ONO-2506 to rats with SCI in order to evaluate its effectiveness in improving motor function and protecting against histological injury. Methods: All rats underwent laminectomy with SCI at the 10th thoracic vertebra. Rats were divided into 3 groups that received different concentrations of ONO-2506 as follows: 10mg/kg (Group I) and 20mg/kg (Group II). The third group (control group) was administered only saline. ONO-2506 or saline was administered by intravenous injection for a week after SCI. Recovery of motor function was assessed by determining the Basso, Beattie, and Bresnahan (BBB) scores and using the %grip test. Using immunohistochemistry, S100 protein and glial fibrillary acidic protein expression was assessed at week 12 post SCI. Results: The BBB score of Group II was significantly better than that of the control group. At week 12 post SCI, the %grip was 43.0% in Group II and 20.3% in Group I. The score for the %grip test was greater for Group II than for the control group (7.0%); thus, motor function improvement appeared to be dose dependent. Regarding immunostaining evaluation, S100 protein staining was lower in Group II compared to the control group, and the astrocytic morphology resembled that of normal spinal cord sections. The SCI lesion expanded from the injured site to both proximal and distal sites in the control group and in Group I. However, despite the presence of cavitation, secondary expansion of the SCI lesion was prevented in Group II as a result of inhibition of S100 protein. Conclusions: Administration of ONO-2506 (20mg/kg) improves motor function and inhibits expansion of secondary injury in SCI rats. [Copyright &y& Elsevier]

Abstract: Ocean acidification caused by anthropogenically elevated CO2 concentration in the atmosphere can pose a critical threat to calcifying marine organisms and coral reef ecosystems. However, because of temporally and spatially limited instrumental pH records, little is known about the actual long-term trend and natural variability of seawater pH during the past century. We present an annually resolved time series of a pH proxy record for 1940–1999 using boron-isotope composition (δ11B) in a modern massive Porites coral from Guam Island (NW Pacific). When superimposed onto interannual variability, the data show a slightly decreasing trend of ~0.39‰ (equivalent to ~0.05–0.08pH units for surface water pH) in the northwestern tropical Pacific since the mid-20th century. This first reported, coral-based reconstruction of long-term open ocean pH is a unique archive for ocean acidification trend in the North Pacific Ocean for the past, which, along with δ11B records from South Pacific corals, can be an important key to ascertaining the extent and rapidity of actual acidification in the Pacific Ocean in the future. [Copyright &y& Elsevier]

An organic matrix consisting of a protein-polysaccharide complex is generally accepted as an important medium for the calcification process. While the role this “calcified organic matrix” plays in the calcification process has long been appreciated, the complex mixture of proteins that is induced and assembled during the mineral phase of calcification remains uncharacterized in many organisms. Thus, we investigated organic matrices from the calcitic sclerites of a soft coral, Sinularia sp., and used a proteomic approach to identify the functional matrix proteins that might be involved in the biocalcification process. We purified eight organic matrix proteins and performed in-gel digestion using trypsin. The tryptic peptides were separated by nano-liquid chromatography (nano-LC) and analyzed by tandem mass spectrometry (MS/MS) using a matrix-assisted laser desorption/ionization (MALDI) – time-of-flight-time-of-flight (TOF-TOF) mass spectrometer. Periodic acid Schiff staining of an SDS-PAGE gel indicated that four proteins were glycosylated. We identified several proteins, including a form of actin, from which we identified a total of 183 potential peptides. Our findings suggest that many of those peptides may contribute to biocalcification in soft corals. [ABSTRACT FROM AUTHOR]

The Dauki fault is a major fault along the southern boundary of the Shillong plateau that may be a source of destructive seismic hazards for the adjoining areas, including northeastern Bangladesh. In this study, we simulated the present stress distribution and the ongoing convergence deformation within the study area using numerical simulation. This simulation attempts to determine the proper dip angle of the Dauki fault from a variety of differently established models but with the same realistic boundary conditions. The simulated stress field helped to predict the type of tectonic environment and the faulting patterns of the study area. The best-fit model can account for the compressive stress regime in the study area, except in the uppermost part of the Shillong plateau, the Bengal basin, and Assam areas where extensional stress regimes exists. In the model, the elements for which Mohr-Coulomb's failure occurs correspond with the observed earthquake data that refer to the Dauki fault as a north-dipping thrust fault. [ABSTRACT FROM AUTHOR]

In the Quaternary, the Ryukyu Islands evolved from a continental margin arc to an island arc by backarc spreading of the Okinawa Trough, accompanied by subsidence and isolation of the islands, a process that has continued to the present. Trough-parallel half grabens were filled with marine siltstone. Similar sediments filling orthogonal fault-controlled and west-draining non-tectonic valleys record island separation. New Quaternary nannofossil biostratigraphic data date the deposition of the marine siltstone at 1.552 ± 0.154 Ma. At that time, the entire 1000 km-long island chain comprising the Ryukyu Islands separated from the Asian continent by rifting extending from the Okinawa Trough to the Tsushima Strait. The Tokara, Kerama, and Yonaguni gaps, branched or transverse rifts of the Okinawa Trough, separate the island chain into subgroups of the Osumi, Amami, Okinawa, and Yaeyama islands, and Taiwan. The shallow Taiwan Strait separated Taiwan from the Chinese mainland. The Kuroshio warm current that previously ran offshore of the continental margin arc began to enter the opening backarc basin through the Yonaguni gap and to exit through the Tokara gap, flowing along the axis of the Okinawa Trough. Under influence of the warm current and because of entrapment of continentally sourced detrital sediments by the Okinawa Trough, coral reefs formed around each island. These reefs make up a unit called the Ryukyu limestone. Subsidence continued through the deposition of this limestone, resulting in further isolation of each island. Some islands did not separate from the mainland but emerged above sea level later as a result of volcanic edifice construction or forearc uplift. Following initial isolation, the Japanese islands and Taiwan may have been connected to the mainland by land bridges during some sea level low stands related to glacial periods, whereas the other islands remained isolated. Based on ages of isolation of each island, a Quaternary palaeogeographic map and ‘phylogenetic tree’ of the islands can be drawn showing the separation time of each island from the mainland and from each other. This information should be useful for phylogenetic molecular biologists studying evolution of Ryukyu endemic species and vicariant speciation and could facilitate analysis of the DNA substitution rate. [ABSTRACT FROM AUTHOR]

Mantle xenoliths entrained in Quaternary alkaline basalts from the Turkana Depression in southern Ethiopia (the East Africa Rift) were studied for their geochemical and Sr-Nd-Pb isotopic compositions to constrain the evolution of the lithosphere. The investigated mantle xenoliths are spinel lherzolites in composition with a protogranular texture. They can be classified into two types: anhydrous and hydrous spinel lherzolites; the latter group characterized by the occurrences of pargasite and phlogopite. The compositions of whole-rock basaltic component (CaO = 3.8-5.6 wt%, AlO = 2.5-4.1 wt%, and MgO = 34.7-38.1 wt%), spinel (Cr# = 0.062-0.117, AlO = 59.0-64.4 wt%) and clinopyroxene (Mg# = 88.4-91.7, AlO = 5.2-6.7 wt%) indicate that the lherzolites are fertile and have not experienced significant partial melting. Both types are characterized by depleted Sr/Sr (0.70180-0.70295) and high Nd/Nd (0.51299-0.51348) with wide ranges of Pb/Pb (17.86-19.68) isotopic compositions. The variations of geochemical and isotopic compositions can be explained by silicate metasomatism induced by different degree of magma infiltrations from ascending mantle plume. The thermobarometric estimations suggest that the spinel lherzolites were derived from depths of 50-70 km (15.6-22.2 kb) and entrained in the alkaline magma at 847-1,052°C. Most of the spinel lherzolites from this study record an elevated geotherm (60-90 mW/m) that is related to the presence of rising mantle plume in an active tectonic setting. Sm-Nd isotopic systematic gives a mean T model age of 0.95 Ga, interpreted as the minimum depletion age of the subcontinental lithosphere beneath the region. [ABSTRACT FROM AUTHOR]

Major and trace element and isotopic ratios (Sr, Nd and Pb) are presented for mafic lavas (MgO > 4 wt%) from the southwestern Yabello region (southern Ethiopia) in the vicinity of the East African Rift System (EARS). New K/Ar dating results confirm three magmatic periods of activity in the region: (1) Miocene (12.3-10.5 Ma) alkali basalts and hawaiites, (2) Pliocene (4.7-3.6 Ma) tholeiitic basalts, and (3) Recent (1.9-0.3 Ma) basanite-dominant alkaline lavas. Trace element and isotopic characteristics of the Miocene and Quaternary lavas bear a close similarity to ocean island basalts that derived from HIMU-type sublithospheric source. The Pliocene basalts have higher Ba/Nb, La/Nb, Zr/Nb and Sr/Sr (0.70395-0.70417) and less radiogenic Pb isotopic ratios (Pb/Pb = 18.12-18.27) relative to the Miocene and Quaternary lavas, indicative of significant contribution from enriched subcontinental lithospheric mantle in their sources. Intermittent upwelling of hot mantle plume in at least two cycles can explain the magmatic evolution in the southern Ethiopian region. Although plumes have been originated from a common and deeper superplume extending from the core-mantle boundary, the diversity of plume components during the Miocene and Quaternary reflects heterogeneity of secondary plumes at shallower levels connected to the African superplume, which have evolved to more homogeneous source. [ABSTRACT FROM AUTHOR]

Abstract: We performed numerical simulations to determine the contemporary maximum horizontal compressive stress (σ Hmax) in the northeast India region, the Bengal basin (Bangladesh), and the adjoining Indo-Burma Ranges, with different boundary conditions. The regional tectonic stress was simulated using the finite element method (FEM) under the plane stress condition. Most of the study areas show NE–SW regional stress orientation, which is consistent with other stress indicators, such as earthquake focal mechanism solutions. The E–W trending Dauki fault, which separates the Shillong plateau to the north from the Bengal basin to the south, plays a major role in the stress distribution and regional deformation. This fault alone accommodates ∼25% of the regional surface displacement rate of the study area. The fault pattern of the study area was also simulated using rheological parameters and the Mohr–Coulomb failure criterion. The simulated results reproduce the observed tectonic state of the area, including a strike-slip regime along the Dauki fault, in the southwestern part of the Bengal basin, and in the Tripura fold belt areas. The modeling indicates that the Brahmaputra valley to the north of the Shillong plateau and to the south of the Himalayan frontal thrust exhibits thrust/reverse faulting with a strike-slip component, and in the Indo-Burma Ranges, strike-slip faulting is predominant with a reverse fault component. [ABSTRACT FROM AUTHOR]

Abstract: Fault reactivation during underground mining is a critical problem in coal mines worldwide. This paper investigates the mining-induced reactivation of faults associated with the main conveyor belt roadway (CBR) of the Barapukuria Coal Mine in Bangladesh. The stress characteristics and deformation around the faults were investigated by boundary element method (BEM) numerical modeling. The model consists of a simple geometry with two faults (Fb and Fb1) near the CBR and the surrounding rock strata. A Mohr-Coulomb failure criterion with bulk rock properties is applied to analyze the stability and safety around the fault zones, as well as for the entire mining operation. The simulation results illustrate that the mining-induced redistribution of stresses causes significant deformation within and around the two faults. The horizontal and vertical stresses influence the faults, and higher stresses are concentrated near the ends of the two faults. Higher vertical tensional stress is prominent at the upper end of fault Fb. High deviatoric stress values that concentrated at the ends of faults Fb and Fb1 indicate the tendency towards block failure around the fault zones. The deviatoric stress patterns imply that the reinforcement strength to support the roof of the roadway should be greater than 55MPa along the fault core zone, and should be more than 20MPa adjacent to the damage zone of the fault. Failure trajectories that extend towards the roof and left side of fault Fb indicate that mining-induced reactivation of faults is not sufficient to generate water inflow into the mine. However, if movement of strata occurs along the fault planes due to regional earthquakes, and if the faults intersect the overlying Lower Dupi Tila aquiclude, then liquefaction could occur along the fault zones and enhance water inflow into the mine. The study also reveals that the hydraulic gradient and the general direction of groundwater flow are almost at right angles with the trends of faults Fb and Fb1, which could act as barriers to groundwater flow into the mines. [Copyright &y& Elsevier]

Abstract: This paper uses two-dimensional boundary element method (BEM) numerical modeling to analyze the deformation and failure behavior of a coal seam and to understand the nature of gas flow into a roadway entering the Barapukuria coal mine in Bangladesh. The Barapukuria basin contains Permian-aged Gondwana coals with high volatile B bituminous rank. Three models (A, B, and C) are presented here. Model A assumes horseshoe-shaped geometry, model B assumes trapezoid-shaped geometry, and model C assumes horseshoe-shaped geometry coupled with a roof fall-induced cave generated by the break-up of rock materials along the vertical dimension of an igneous dyke. The simulation results show that there is little difference in strata deformation between models A and B. In model A, there is no horizontal tensional stress and the overall horizontal stress patterns are compressive, while the distribution and magnitude of vertical stress show higher tensional stresses on the immediate rib sides and floor. In model B, both horizontal and vertical stress distributions indicate low to medium tensional stresses on the immediate roof, floor, and rib sides, but compressive stresses are prominent toward the interior of the coal seam. Deformation vectors indicate that failure extends laterally to about 7.5 m around the excavation geometry. On the contrary, for model C, the distributions and magnitudes of horizontal and vertical stress show higher tensional stresses in both rib sides of the roof fall zone. The deformation around the dyke-induced perturbation zone affects a large volume of coal. The deformation vectors with high magnitudes are nearly horizontal and propagate laterally up to 30 m; whereas, low-magnitude deformation vectors extend about 25 m toward the roof and 20 m toward the floor. The vertical tensional displacement, which is concentrated in the floor and the left and right hand sides of the roof, propagates about 30 m on both sides and about 22 m in the floor. From these simulation results, it is thought that the extension of the dyke-induced perturbation zone toward the roof, floor, and rib sides of the entry roadway initially creates small tensional cracks that gradually grow into large-scale tensional features. These features could also be responsible for high concentrations of gas, which are emitted into the mine from fractured coals due to insufficient mine ventilation and low atmospheric pressure. [Copyright &y& Elsevier]

Abstract: Several identified ‘active faults’ located in the southwest Ryukyu area may be an origin of M5-class earthquakes taking place frequently every year, sometimes of M7-class earthquakes which cause a severe geohazard in this area. ‘The East Ishigaki Fault’, one of the ‘officially identified’ active faults, was studied precisely by multibeam echo sounding and the in-situ ROV observation. The survey expedition figured the topographic feature of the fault clearly and more precisely than that mapped by the Hydrographic Department of Japan. The survey also identified the locations of northwestern and southeastern termini of the fault, which revealed the total length to be 44 km: corresponding to a M7.4 earthquake. The new topographic map shows that the fault is composed of four or five segments with maximum vertical offset of ∼80 m in the southernmost segment; not all of the segment can slip at once. A reconnaissance survey of three of these segments by the ROV Hyper-Dolphin dives during the same expedition revealed that the headwall scarp is an outcrop made up of the Ryukyu Limestone of the Middle Pleistocene and that the lower scarp and the trough are covered with mostly talus apparently from the headwall. At least two of these segments look fresher in fault activity rather than the others, though all the observations show very recent activities along the fault. Based on these results, the East Ishigaki Fault, at least some of the segments, might cause the 1771 tsunami and also future tsunamis with the similar magnitude. [Copyright &y& Elsevier]

We explore the tectono-magmatic processes in the western West Philippine Basin, Philippine Sea Plate, using bathymetric data acquired in 2003 and 2004. The northwestern part of the basin formed through a series of northwestward propagating rifts. We identify at least five sequences of propagating rifts, probably triggered by mantle flow away from the mantle thermal anomaly that is responsible for the origin of the Benham and Urdenata plateaus. Gravitational forces caused by along-axis topographic gradient and a ∼30° ridge reorientation appear to also be driving the rift propagations. The along-axis mantle flow appears to be reduced and deflected along the Luzon-Okinawa fracture zone, because the spreading system remained stable west of this major fault zone. North-east of the Benham plateau, a left-lateral fracture zone has turned into a NE–SW-trending spreading axis. As a result, a microplate developed at the triple junction. [ABSTRACT FROM AUTHOR]

Provides information on a study which discussed geochemical variation within the northern Ryukyu arc. Tectonic and geological setting and samples; Analytical methods; Major and trace element compositions; Details on lead, strontium and neodymium isotopic compositions.

• Widespread Pleistocene basalt volcanism in Krông Nô, Dac Nong, Vietnam, is reported. • Four basalt volcanic centers occur along a regional extensional fault. • The basalts are tholeiitic and alkaline types having distinct geochemical character. • The magmas reflect column melting from low- to high-melting temperature and pressure. • The volcanism is India-Eurasian collision-induced rather than mantle-plume derived. Basaltic and related- pyroclastic products aged 0.67, 0.46 and 0.2 Ma produced by eruption of Chư B'luk (Buon Choah), Phu Son (Pass 52, Quang Phu) volcanoes in the Krông Nô district, and Ea T'ling and Nam Dong volcanoes in the Cu Jut district covers an area of 120 km2 with a thickness of a few meters to about 80 m. The volcanoes are aligned along a sub-meridian oriented extensional fault, from Phu Son in the south via Chư B'luk, Ea T'ling in the middle to Nam Dong in the north. The basalts are divided into geochemically alkaline and tholeiitic groups. Ne-normative alkaline basalts include samples from the upper layer of Phu Son volcano, those in the Trinh Nu waterfall area (Ea T'ling volcano) and cored samples conducted near the Dray Sap waterfall. Q-normative tholeiitic basalts include all the samples from Chư B'luk and Nam Dong volcanoes, and massive basalts in the lower layer of Phu Son volcano. Geochemically the tholeiitic basalts are vastly different from the alkaline basalts in that they have higher SiO 2 (50–55 wt% compared to <47 wt% in alkaline basalt), Al 2 O 3 (>14–16 wt% compared to <14 wt%), lower K 2 O (<1.5 wt% compared to >1.5–2.5 wt%) and lower TiO 2 (<1.8 wt% as compared to >2 wt% in alkaline basalt). Melting temperature and pressure calculations based on computing primitive melt compositions showed that the tholeiitic basalts may be produced in a narrow temperature range of 1365–1385 °C, corresponding to pressure of 1.2–1.6 GPa. The alkaline basalts may be produced in a temperature range between 1400 and 1440 °C and pressure varying from 3.1 to 3.35 GPa. Both the tholeiitic and alkaline basalts are free of crustal contamination. They show geochemically similar characteristics to those of continental intraplate basalts although the alkaline basalt show much more enrichment in incompatible elements. The 87Sr/86Sr and 143Nd/144Nd ratios of the two basaltic groups are quite similar, varying within narrow ranges of, respectively, 0.7038–0.7041, 0.5129–0.51286 but their 206Pb/204Pb isotopic ratios vary widely relative to 207Pb/204Pb and 208Pb/204Pb suggesting their interaction with different isotopic components and/or isotopic evolution history. Isotopic modeling relative to major mantle isotopic components suggests that the alkaline basalts may be generated by interaction between an N-MORB-like and an enriched mantle type 1 (EM1) at deep levels. The isotopic component is usually known as DUPAL-like regional mantle isotopic anomaly believed to be widespread in SE Asian mantle. The isotopic compositions of tholeiitic basalt may be generated by mixing between the DUPAL-like component with an enriched mantle type 2 (EM2)-like at higher levels in the lithospheric mantle. [ABSTRACT FROM AUTHOR]

Background: Lumbar disc herniation (LDH) is most common in men aged 20-40 at the L4/5 level; however, left-right differences have not been reported. Improving our understanding of left- and right-side LDH may facilitate the estimation of mechanical load on intervertebral discs. Here, we assessed left-right differences in LDH via a retrospective analysis of LDH cases.Methods: Among 10,972 surgical cases of LDH identified in the Nagoya Spine Group database, 2899 in which right- and left-LDH sides were observable in a single vertebral segment were identified (mean age 46.3 ± 16.6 years, 2028 males). The following characteristics of patients with right- and left-LDH were compared: age, LDH level, surgical technique, operative time, blood loss, length of hospital stay, preoperative Japan Orthopaedic Association (JOA) score, and JOA recovery rate.Results: LDH occurred on the right and left sides in 1358 and 1541 patients, respectively, with patients with right-side LDH significantly older than those with left (47.9 ± 16.6 versus 45.0 ± 16.5, respectively; p < 0.001). No between-group differences in sex, age, LDH level, surgical technique, operative time, blood loss, length of hospital stay, preoperative JOA score, or JOA recovery rate were observed. The occurrence of right-side LDH increased with age, occurring in 42.7%, 45.1%, 49.9%, and 54.7% of patients aged 10-29, 30-49, 50-69, and 70-89 years, respectively.Conclusion: Left-side LDH was observed more frequently than right; however, right-side LDH incidence increased with age. No significant between-group differences regarding symptoms, treatments, or outcomes were observed. [ABSTRACT FROM AUTHOR]

Major-element and trace-element geochemistry of fresh volcanic glass, and the whole-rock Hf and Nd isotopic compositions of volcanic rocks from the Oman Ophiolite were used to understand the extent to which slab-derived fluids and melts were involved in magma generation during incipient arc development. The spreading stage (V1) samples have trace-element characteristics similar to those of mid-ocean-ridge basalts, with Hf and Nd isotopic compositions of the Indian mantle domain. The incipient arc stage (V2) volcanic glasses have lower abundances of high field strength elements (HFSEs) and middle and heavy rare earth elements (MREEs and HREEs), and higher abundances of large ion lithophile elements (LILEs) than the V1 glasses. Progressive increases in B, Pb, and LILEs in the V2 stage glasses with age indicate an increasing contribution of slab-derived fluids from earlier arc tholeiite (LV2) to later boninite (UV2). The LV2 was generated by the contribution of amphibolite-derived fluid. The UV2 is subdivided into low-Si UV2 and high-Si UV2 magmas, with the former having lower SiO 2 , and LILE, and higher Na 2 O, HFSE and REE concentrations than the latter. The low-Si UV2 magma was generated with the involvement of high-temperature slab-derived fluid. In contrast, the high-Si UV2 shows a spoon-shaped trace-element pattern and Hf and Nd isotope chemistry, indicating the involvement of sediment melt in its magma genesis. Decreasing HFSEs and HREEs in the magmas with age indicate progressive depletion of the source mantle during the V2 arc magmatism, suggesting an absence of convection in the mantle wedge that resulted from subduction of a hot, buoyant slab beneath young, hot lithosphere. [ABSTRACT FROM AUTHOR]

The Late Cretaceous to Early Cenozoic magmatism in the South China coastal area produced some amounts of rhyolitic rocks in two phases, which may be used to unravel the geohistory of the epilog of the paleo-Pacific plate subduction system. Essence of the Phase I rocks is the high temperature rhyolite (A-type)-trachydacite association in north Fujian (95–91 Ma) that was coeval with regional A-type granites. They succeeded the vast rhyolite–dacite–andesite (RDA) associations and I-type granitoids (113.5–96 Ma) and preceded the silicic-dominating rhyolite/basalt bimodal suites or monolithologic rhyolite in Zhejiang (89–86 Ma). Phase II rocks include (a) the RDA association or rhyolite alone in some drifted continental fragments nearby (83–56 Ma) and (b) the following rift-basin related rhyolite–trachyte/basalt bimodal suites in Guangdong and west Taiwan (56–38 Ma). The silicic volcanism, spatially changed from a NE–SW to the nearly E–W direction after 83 Ma, may reflect tectonic-driven eruptions occurred in the post-orogenic extensional (Phase I), resumed plate subducting (Phase IIa) and continental margin rifting (Phase IIb) stages. Rhyolitic rocks basically are shoshonitic to high-K calc-alkaline affinities while the Phase IIa RDA associations are mostly concentrated in the high-K to medium-K calc-alkaline series. All these rocks generally possess a continental arc character in tectonic discrimination diagrams, except shoshonitic rocks that have within-plate signatures. Based on the trace element and Nd–Pb isotope data, A-type rocks are suggested to have derived from mixing between trachydacitic (or syenitic) magmas and crustal melts of various sources under the high temperature condition (±metasomatism), and the succeeding silicic rocks are derivatives of the contaminated lithospheric mantle melts through crystal fractionation. On the other hand, Phase II silicic rocks are mainly the fractionation products of mafic magmas originated either from the lithospheric or the asthenospheric mantle. In reflection to such magmatotectonics with time, break-off of the subducted slab shortly before 113.5 Ma, change of the plate-moving direction between 86 and 83 Ma, and termination of plate movement probably at ∼56 Ma signify the epilog of the paleo-Pacific plate. [ABSTRACT FROM AUTHOR]

Purpose: To determine the most valid bone health parameter to predict mechanical complications (MCs) following surgery for adult spinal deformity (ASD).This multicenter study retrospectively examined the records of patients who had undergone fusion of three or more motion segments, including the pelvis, with a minimum two-year follow-up period. Patients with moderate and severe global alignment and proportion scores were included in the study and divided into two groups: those who developed MCs and those who did not. Bone mineral density (BMD) of the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry, and Hounsfield units (HUs) were measured in the lumbar spine on computed tomography. Radiographic parameters were evaluated preoperatively, immediately after surgery, and at final follow-up.Of 108 patients, 30 (27.8%) developed MCs, including 26 cases of proximal junctional kyphosis/failure, 2 of distal junctional failure, 6 of rod fracture, and 11 reoperations. HUs were significantly lower in patients who experienced MCs (113.7 ± 41.1) than in those who did not (137.0 ± 46.8; P = 0.02). BMD did not differ significantly between the two groups. The preoperative and two-year postoperative global tilt, as well as the immediately postoperative sagittal vertical axis, were significantly greater in patients who developed MCs than in those who did not (P = 0.02, P < 0.01, and P = 0.01, respectively).Patients who experienced MCs following surgery for ASD had lower HUs than those who did not. HUs may therefore be more useful than BMD for predicting MCs following surgery for ASD.Methods: To determine the most valid bone health parameter to predict mechanical complications (MCs) following surgery for adult spinal deformity (ASD).This multicenter study retrospectively examined the records of patients who had undergone fusion of three or more motion segments, including the pelvis, with a minimum two-year follow-up period. Patients with moderate and severe global alignment and proportion scores were included in the study and divided into two groups: those who developed MCs and those who did not. Bone mineral density (BMD) of the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry, and Hounsfield units (HUs) were measured in the lumbar spine on computed tomography. Radiographic parameters were evaluated preoperatively, immediately after surgery, and at final follow-up.Of 108 patients, 30 (27.8%) developed MCs, including 26 cases of proximal junctional kyphosis/failure, 2 of distal junctional failure, 6 of rod fracture, and 11 reoperations. HUs were significantly lower in patients who experienced MCs (113.7 ± 41.1) than in those who did not (137.0 ± 46.8; P = 0.02). BMD did not differ significantly between the two groups. The preoperative and two-year postoperative global tilt, as well as the immediately postoperative sagittal vertical axis, were significantly greater in patients who developed MCs than in those who did not (P = 0.02, P < 0.01, and P = 0.01, respectively).Patients who experienced MCs following surgery for ASD had lower HUs than those who did not. HUs may therefore be more useful than BMD for predicting MCs following surgery for ASD.Results: To determine the most valid bone health parameter to predict mechanical complications (MCs) following surgery for adult spinal deformity (ASD).This multicenter study retrospectively examined the records of patients who had undergone fusion of three or more motion segments, including the pelvis, with a minimum two-year follow-up period. Patients with moderate and severe global alignment and proportion scores were included in the study and divided into two groups: those who developed MCs and those who did not. Bone mineral density (BMD) of the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry, and Hounsfield units (HUs) were measured in the lumbar spine on computed tomography. Radiographic parameters were evaluated preoperatively, immediately after surgery, and at final follow-up.Of 108 patients, 30 (27.8%) developed MCs, including 26 cases of proximal junctional kyphosis/failure, 2 of distal junctional failure, 6 of rod fracture, and 11 reoperations. HUs were significantly lower in patients who experienced MCs (113.7 ± 41.1) than in those who did not (137.0 ± 46.8; P = 0.02). BMD did not differ significantly between the two groups. The preoperative and two-year postoperative global tilt, as well as the immediately postoperative sagittal vertical axis, were significantly greater in patients who developed MCs than in those who did not (P = 0.02, P < 0.01, and P = 0.01, respectively).Patients who experienced MCs following surgery for ASD had lower HUs than those who did not. HUs may therefore be more useful than BMD for predicting MCs following surgery for ASD.Conclusion: To determine the most valid bone health parameter to predict mechanical complications (MCs) following surgery for adult spinal deformity (ASD).This multicenter study retrospectively examined the records of patients who had undergone fusion of three or more motion segments, including the pelvis, with a minimum two-year follow-up period. Patients with moderate and severe global alignment and proportion scores were included in the study and divided into two groups: those who developed MCs and those who did not. Bone mineral density (BMD) of the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry, and Hounsfield units (HUs) were measured in the lumbar spine on computed tomography. Radiographic parameters were evaluated preoperatively, immediately after surgery, and at final follow-up.Of 108 patients, 30 (27.8%) developed MCs, including 26 cases of proximal junctional kyphosis/failure, 2 of distal junctional failure, 6 of rod fracture, and 11 reoperations. HUs were significantly lower in patients who experienced MCs (113.7 ± 41.1) than in those who did not (137.0 ± 46.8; P = 0.02). BMD did not differ significantly between the two groups. The preoperative and two-year postoperative global tilt, as well as the immediately postoperative sagittal vertical axis, were significantly greater in patients who developed MCs than in those who did not (P = 0.02, P < 0.01, and P = 0.01, respectively).Patients who experienced MCs following surgery for ASD had lower HUs than those who did not. HUs may therefore be more useful than BMD for predicting MCs following surgery for ASD. [ABSTRACT FROM AUTHOR]

In this study, mineralogical, geochemical, and isotopic data are presented for the Sylhet Trap at the southern flank of the eastern Shillong Plateau, northeastern India, to determine the magma genesis in relation to the Kerguelen plume mantle source. Sylhet Trap rocks are porphyritic tholeiite and have diverse chemical compositions from picro-basalt, basalt, andesite to dacite, but mostly are within the subalkaline field. Major and trace element data were used to identify two distinct magma fractionation trends, a low and medium K series, characterized by relatively flat MORB-like (analogous to Rajmahal Traps (II)) and enriched OIB chondrite-normalized Rare Earth Element (REE) patterns. Initial Sr/Sr, Nd/Nd, and Pb/Pb isotope compositions were widely varied, ranging from 0.70435-0.71357, 0.51196-0.51266, and 17.92-19.72, respectively, when compared with basalts from the West Bengal, the Rajmahal Traps and the Kerguelen plume. Correlations among isotopic and trace element ratios of the Sylhet Traps provide evidence for the involvement of (1) HIMU-like mantle component, (2) the Kerguelen plume-like component, and (3) EMII-like crustal component. Magma from the Sylhet Traps was originated from a melting that derived directly from the heterogeneous Kerguelen mantle plume (components 1 and 2), which strongly suggests the presence of the Kerguelen plume-head in the Bengal basin. [ABSTRACT FROM AUTHOR]

We applied a new geoarchaeological method with two carbonate archives, which are fossil snails from Sakitari Cave and stalagmites from Gyokusen Cave, on Okinawa Island, Japan, to reconstruct surface air temperature changes over the northwestern Pacific since the last glacial period. Oxygen isotope ratios (δ18O) of modern and fossil freshwater snail shells were determined to infer seasonal temperature variations. The observational and analytical data confirm that δ18O values of fluid inclusion waters in the stalagmite can be regarded as those of spring waters at the sites where snails lived. Our results indicate that the annual mean, summer, and winter air temperatures were lower by 6–7 °C at ca. 23 thousand years ago (ka) and 4–5 °C at ca. 16–13 ka than those of the present day. Our reconstruction implies that surface air cooling was possibly two times greater than that of seawater around the Ryukyu Islands during the Last Glacial Maximum, which potentially enhanced the development of the East Asian summer monsoon during the last deglaciation. Considering the potential uncertainties in the temperature estimations, the climatic interpretations of this study are not necessarily definitive due to the limited number of samples. Nevertheless, our new geoarchaeological approach using coupled δ18O determinations of fossil snails and stalagmite fluid inclusion waters will be useful for reconstructing snapshots of seasonally resolved time series of air temperatures during the Quaternary. [ABSTRACT FROM AUTHOR]

Basic volcanic rocks from the West Nain area of the Urumieh–Dokhtar Magmatic Assemblage demonstrate significant subduction-related geochemical characteristics; these along with the new age data obtained for the volcanic rocks shed new light on the geodynamic evolution of the Iranian segment of Alpine–Himalayan orogeny. The late Oligocene (26.5 Ma) high-Nb basic volcanic rocks are likely to represent a transient rather enriched asthenospheric mantle underlying the otherwise dominantly Eocene–early Oligocene West Nain island arc. Lithospheric mantle geochemical signatures of the low-Zr volcanic rocks (20.6 Ma) and high-Th volcanic rocks (19.7 Ma) imply replacement of the underlying mantle. The substitution of asthenospheric mantle by a lithospheric mantle wedge might have been associated with – or perhaps caused by – an increase in the subduction rate. Culmination of the West Nain magmatism into slab melting that produced the early Miocene (18.7 Ma) adakitic rocks is compatible with subsequent ascent that triggered slab decompression melting. [ABSTRACT FROM AUTHOR]

We determined quantitative and qualitative alterations in lipids during the occurrence and progression of spinal cord injury (SCI) in rats to identify potential clinical indicators of SCI pathology. Imaging mass spectrometry (IMS) was used to visualize twelve molecular species of phosphatidylcholine (PC) on thin slices of spinal cord with SCI. In addition, twelve species of phospholipids and five species of prostaglandins (PGs) were quantified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) of lipid extracts from control/injured spinal cords. Unique distribution patterns were observed for phospholipids with different fatty acid compositions, and distinct dynamic changes were seen in both their amounts and their distributions in tissue as tissue damage resulting from SCI progressed. In particular, PCs containing docosahexaenoic acid localized to the large nucleus in the anterior horn region at one day post-SCI and rapidly decreased thereafter. In contrast, PCs containing arachidonic acid (AA-PCs) were normally found in the posterior horn region and were intensely and temporarily elevated one week after SCI. Lysophosphatidylcholines (LPCs) also increased at the same SCI stage and in regions with elevated AA-PCs, indicating the release of AA and the production of PGs. Moreover, LC-ESI-MS/MS analysis of lipid extracts from the spinal cord tissue at the impact site demonstrated a peak in PGE2 that reflected the elevation/reduction pattern of AA-PCs and LPC. Although further investigation is required, we suggest that invasive immune cells that penetrated from the impaired blood-brain barrier at 1-2 weeks post-SCI may have produced LPCs, released AA from AA-PCs, and produced PGs in SCI tissue at sites enriched in AA-PCs/LPC. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we demonstrate a key function of extracellular matrix proteins (ECMPs) on seed crystals, which are isolated from calcified endoskeletons of soft coral and contain only CaCO3 without any living cells. This is the first report that an ECMP protein extracted from a marine organism could potentially influence in modifying the surface of a substrate for designing materials via crystallization. We previously studied with the ECMPs from a different type of soft coral (Sinularia polydactyla) without introducing any seed crystals in the process, which showed different results. Thus, crystallization on the seed in the presence of ECMPs of present species is an important first step toward linking function to individual proteins from soft coral. For understanding this interesting phenomenon, in vitro crystallization was initiated in a supersaturated solution on seed particles of calcite (104) with and without ECMPs. No change in the crystal growth shape occurred without ECMPs present during the crystallization process. However, with ECMPs, the morphology and phase of the crystals in the crystallization process changed dramatically. Upon completion of crystallization with ECMPs, an attractive crystal morphology was found. Scanning electron microscopy (SEM) was utilized to observe the crystal morphologies on the seeds surface. The mineral phases of crystals nucleated by ECMPs on the seeds surface were examined by Raman spectroscopy. Although 50mM Mg2+ is influential in making aragonite in the crystallization process, the ECMPs significantly made calcite crystals even when 50mM Mg2+ was present in the process. Crystallization with the ECMP additive seems to be a technically attractive strategy to generate assembled micro crystals that could be used in crystals growth and design in the Pharmaceutical and biotechnology industries. [Copyright &y& Elsevier]

Abstract: There is an ongoing debate concerning whether the vast Nanling Mountain granitoids of South China are the result of Jurassic paleo-Pacific subduction. We address this question by examining two Mesozoic basalt successions in South China, one parallel and the other oblique to the convergence boundary between the paleo-Pacific plate and South China continent. The geochemical characteristics of these basalts are used to constrain the influence of this presumed subduction system on mantle composition. 40Ar/39Ar age, major element and trace element abundances, and Sr, Nd and Pb isotope data indicate that the northeast-southwest trending basalts in the Southeast Coast Magmatic Belt that formed during 101–76 Ma exhibit arc-like signatures and are derived from subduction-modified mantle. However, the east–west trending basalt array extending from the Cathaysia Interior to the Cathaysia Folded Belt, which decreases in age from 175 to 98 Ma in an eastward direction, is characterized by lithosphere-modified OIB-like asthenosphere composition, except for a few younger rocks from Huichang which resemble Southeast Coast Magmatic Belt basalts. These results suggest that the Jurassic mantle beneath the Cathaysia Interior and the Cathaysia Folded Belt was rather homogeneous and undisturbed, and was not affected by the paleo-Pacific subduction system. Alternatively, post-orogenic (Indosinian) extension accompanied by mafic underplating may have been the cause of vast Jurassic granitic magmatism in South China. [Copyright &y& Elsevier]

The Aoso volcano is a member of the newly defined volcanic front of Northeast Japan, characterized by the occurrence of low-K and hornblende andesites. Its activity can be divided into three stages: the early, caldera-forming, and late stages. While petrographic and geochemical data show all products underwent magma mixing or co-mingling, Sr and Nd isotopic ratios indicate that all are consanguineous. The end-member magmas are basaltic and andesitic in the early stage, but basaltic and dacitic in the late stage. In the caldera-forming stage, hornblende-free and hornblende-rich andesites co-mingled, which triggered an explosive eruption leading to caldera formation. Hornblende occurs also in the dacite from the early part of the late stage. These hornblende andesites and dacites are lower in magmatic temperature compared to hornblende-free andesites. The estimated basaltic end-member is low-K and high in magmatic temperature, and can be derived by a high degree of partial melting of mantle under the volcanic front. The estimated andesitic and dacitic end-members cannot be derived from the basaltic end-member magma through fractional crystallization, but can be derived from partial re-melting of the solidified low-K basalt, leaving amphibolitic and gabbroic residues, respectively. [ABSTRACT FROM AUTHOR]

Background: Postoperative SSI is a common and potentially serious complication in spine surgery. Seasonal variation occurs in rates of nosocomial infection, with higher rates found in the summer, during which hot, humid conditions may be optimal for proliferation of bacteria. This might also influence the rate of SSI. The purpose of the study was to examine seasonal variation in SSI after PLIF/TLIF surgery, including relationships with experience of surgeons and causal organisms.Methods: Cases with SSI after PLIF/TLIF surgery at 10 facilities between January 1, 2012, and December 31, 2014 were retrieved from a database. Infection was defined based on CDC guidelines for SSIs. Patients were followed for at least two years after surgery. Surgeries were examined in spring (April-June), summer (July-September), autumn (October-December), and winter (January-March). Seasonal variation and other factors with a potential association with SSIs were evaluated.Results: A total of 1174 patients (607 males, 567 females) who underwent PLIF/TLIF surgery were identified. The operations were PLIF (n = 667), TLIF (n = 443), MIS-PLIF (n = 27), and MIS-TLIF (n = 37). The total SSI rate for the 2-year period was 2.5% (29/1174), and the 2-year average SSI rates for surgeries in each season were spring, 2.6% (7/266); summer, 3.9% (13/335); fall, 1.3% (4/302); winter, 1.8% (5/271). The SSI rate was significantly higher in summer than non-summer (3.9% vs. 1.9%, p < 0.05). SSIs were caused by a variety of pathogens, including Gram-positive cocci, and Staphylococcus aureus was the most common pathogenic organism to cause SSI.Conclusion: Seasonality should be taken into account in strategies for SSI prevention, with particular attention on mitigation of increased temperature and humidity in the summer and on infection caused by Gram-positive cocci and S. aureus. [ABSTRACT FROM AUTHOR]

The late Cenozoic geohistory of the Ryukyu arc is closely related to the rifting history of the Okinawa Trough. The submarine geology and stratigraphy of areas around Kume Island, which is situated near the eastern rifted margin of the middle Okinawa Trough, provide key constraints to understand the timing and mode of Okinawa Trough rifting. Here we report the lithology of sedimentary rocks dredged along slopes of ~1000‐m‐deep sea knolls located north and northwest off Kume Island, and their depositional ages determined by calcareous nannofossils and strontium (Sr) isotope analyses. Various types of sedimentary rocks, such as siltstone, very fine‐grained sandstone, medium‐grained sandstone, fossiliferous coarse‐grained sandstone, and tuffaceous sandstone, were recovered at two dredge sites. These sedimentary rocks are lithologically similar to those in the Aka Formation and a part of the Maja Formation of the Shimajiri Group in nearby Kume Island. Calcareous nannofossils and Sr isotope analyses indicate their depositional ages from the early Pliocene to the early Pleistocene, which are generally consistent with those of the Aka Formation. The finding of the dredged rocks similar in lithology and ages to the Aka Formation indicates that marine deltaic area continued toward north and northwest from Kume Island during these periods. The presence of the Shimajiri Group equivalent sedimentary rocks at the dredge sites are likely related to the main rifting of the Okinawa Trough after ca. 2 Ma in the central Ryukyus. [ABSTRACT FROM AUTHOR]

In the Hamadan region, Sanandaj-Sirjan Zone (SaSiZ), W Iran, a pegmatite-aplite vein occurs that contains up to 15 vol% sapphire. The Hamadan sapphire is black to blue, and translucent to opaque, which reveals its semi-gem and gem quality. On the basis of petrographic studies, the Hamadan sapphire-bearing pegmatite-aplite vein represents alkali syenitic to syenitic composition and its adjacent granitoids have a range of composition from syenitic to quartz monzonite and granodiorite. New petrographic, whole-rock geochemical data and δ18O values [9.30–12.45‰VSMOW (Vienna Standard Mean Ocean Water)] suggest crustal origin for the peraluminous, S-type and alkaline sapphire-bearing pegmatite-aplite vein. The presence of syngenetic quartz inclusions in the sapphire, and some similar physical-gemological signatures (e.g., parting patterns and angles) of the Hamadan sapphire and kyanite support the generation of the sapphire at the expense of kyanite. In addition, a secondary metasomatic stage may have played a minor role in formation of the sapphire grains. The results indicate an important role for the mafic magmas in triggering crustal anatexis and gem crystallization in continental subduction zone settings. [ABSTRACT FROM AUTHOR]

We first generated 53‐, 4‐, 10‐, and 9‐year‐long bimonthly time series of oxygen isotopes (δ18O), Sr/Ca, and U/Ca from 4.4 and 4.9 ka corals in Okinawa, Japan. Results indicate that the mid‐Holocene sea surface temperature (SST) and seawater δ18O were <1°C lower and 0.1–0.2‰ higher than today. Spectral analyses of reconstructed SST and seawater δ18O time series revealed East Asia monsoon (EAM) and El Niño/Southern Oscillation (ENSO) variations. Moreover, the latter had a dominant component of decade‐scale hydrologic variations. The Sr/Ca and U/Ca variations with removal of the ENSO component showed larger fluctuations by ~2°C in winter and ~0.6°C in summer at 4.4 ka relative to today, demonstrating (slightly) greater influences of the EAM variation on the northwestern subtropical Pacific in winter (summer) at that time, which are probably caused by enhancement of the EAM intensity and/or a southward migration of the latitudinal circulation. Plain Language Summary: Although sediments and stalagmites play a leading role in Quaternary paleoclimate studies, the slow rates of sedimentation frequently preclude from climate reconstruction on a seasonal or interannual timescale. From geochemical records of fossil corals in Okinawa, Japan, we first reconstructed a >50‐year‐long bimonthly time series of sea surface temperature and seawater oxygen isotope ratios (relating to salinity) during the middle Holocene. The high‐resolution climate proxy records clearly showed seasonal‐, interannual‐, and decade‐scale thermal and hydrologic variations. Our data demonstrate that the mean climate state around Okinawa was slightly cooler and saline during the middle Holocene than it is today. It is particularly interesting that we can provide robust evidence for (slightly) greater influence of the East Asian winter (summer) monsoon variability on the northwestern subtropical Pacific sea surface at that time. Our findings can be a key to elucidating latitudinal variations in the intensity and region of middle Holocene East Asian monsoon, possibly associated with El Niño events. Key Points: Mid‐Holocene bimonthly time series of coral climate proxy were generated, exhibiting seasonal, interannual, and decadal timescale variationCoral data demonstrate the East Asia winter monsoon greatly influenced northwestern subtropical Pacific sea surface temperatures at 4.4 kaReconstructed seawater isotope ratios suggest 10–20 year/cycle hydrological variation dominated the sea surface around the Ryukyu Islands [ABSTRACT FROM AUTHOR]

Subduction zones are the focal points of mass transfer between the surface and deep Earth. Despite their significance, there remains substantial debate regarding the specific mechanisms of material transport from the slab to the overlying magmatic arc. Broadly, models accounting for slab material transport focus on the relative sequence of events promoting arc volcanism and, in particular, whether mobilization of the down-going slab leads or lags mixing with the mantle wedge. To address these uncertainties, we outline the utility of barium (Ba) isotope mass balance in subduction zones as a means to test different slab material transport models. Barium is a highly fluid-mobile element that is significantly enriched in arc magmas and is thus thought to be a sensitive tracer of slab material transport in arcs. We also present qualitative Ba isotopic mass balances for two well-characterized subduction zones—the Aleutian and Ryukyu magmatic arcs—by analyzing the Ba isotope systematics of their respective subduction inputs and outputs. Despite the narrow (and similar) Ba-isotope range of slab inputs to both systems, we find that erupted magmas exhibit systematic variations indicative of a small negative isotope fractionation during Ba mobilization (≈20–40 ppm AMU−1). We suggest that AOC (altered oceanic crust) is not the principal source of these negative isotope values using other geochemical parameters (e.g., Rb/Ba, Pb isotopes), and infer that the Ba isotope composition of AOC—though contributing a minor amount of Ba in these systems—is isotopically heavier than the overlying sediment package and the depleted mantle. Altogether, these findings are significant as they indicate that the magnitude of isotope fractionation associated with Ba mobilization is small relative to the likely isotopic contrast between subduction inputs in other subduction zones, such as beneath areas of strong ocean upwelling (e.g., South Sandwich, Kamchatka). Thus, we propose that the Ba isotope composition of erupted arc magmas holds great promise for constraining the importance of different slab components, which could help address uncertainties regarding the mechanism of slab material transport in subduction zones. [ABSTRACT FROM AUTHOR]

[Display omitted] • 474–512 Ma ages of zircons are in line with the Cadomian basement in Iran. • Sr-Nd-Pb isotopes indicate variable degree of crustal contribution. • Continental rifting happened in a pre-collisional back-arc setting in the Ordovician. The late Proterozoic - early Paleozoic tectono-magmatic evolution of Central Iran is considered to be a result of subduction of the Proto-Tethys Ocean and the amalgamation of Gondwana continental fragments. Here, we present whole-rock geochemistry, Sr-Nd-Pb isotopes and zircon U-Pb-Hf data for monzonite to quartz monzonite from deep drill core in the area of the Iron Anomaly 21-A, Bafq metallogenic province of Central Iran, to decipher the petrogenetic evolution of the mantle during late Proterozoic–early Paleozoic times. The plutonic rocks display enrichment in large-ion lithophile elements (Rb, Ba, K, and Cs), and depletion in high-field-strength elements (Nb, Ta, Ti), typical of continental arcs. Zircon U-Pb ages of the studied rocks are in the range of 474–512 Ma, which is consistent with the general consensus on the age of the Cadomian basement of Central Iran, and the culmination of subduction along northern Gondwana in the early Paleozoic. The isotopic signatures of the samples, e.g., (87Sr/86Sr) i = 0.706 to 0.718, εNd (t) = − 3.3 to + 1.8, (206Pb/204Pb) i = 18.87 to 20.32, (207Pb/204Pb) i = 15.72 to 15.84, (208Pb/204Pb) i = 40.74 to 42.32, and εHf (t) = -4.7 to + 11.6, cover a compositional range of mantle-derived melts with variable degree of contamination by Neoproterozoic continental crust. A setting of back-arc continental rifting is envisaged for the late Neoproterozoic to early Paleozoic magmatism in the Bafq province. [ABSTRACT FROM AUTHOR]

Subduction is the dominant path of modern earth for recycling crustal materials back to mantle. Lithium, a lithophile trace element in silicate rocks, has high solubility in aqueous fluid, and its stable isotopes, 6Li and 7Li, significantly fractionate during the near-surface fluid-rock interaction. The lithium concentration and isotopic value (d7Li) thus show potential in tracing terrestrial components in the juvenile magma. For better understanding the evolution of lithium during and after subduction, new lithium contents and isotopic data of representative Quaternary basalts (SiO2 <53 wt.%) from the middle Okinawa Trough, a back-arc basin located behind the Ryukyu arc, were determined in this study. These basalts have been classified into two types based on their well-characterized trace elemental compositions and Nd-Sr isotopes. Type-I basalts have E-MORB-like geochemical features (eNd(0) = +3.9 - +5.8; ISr = 0.703892 – 0.703961). Type-II basalts, in contrast, have lower Nd isotopic ratios (eNd(0) = +1.5 – +3.8) and radiogenic Sr isotopes (0.704044 – 0.704540) as a result of the involvement of subduction component associated with the Central Ryukyu Arc magmatism. Our analytical results show that type-II basalts (n = 4) have higher Li/Yb (1.8 - 2.2) comparing with type-I basalts (Li/Yb = 1.2 – 1.8; n = 8). However, the fluid indicators, e.g. U/Th, B/Th, Sr/Th and Pb/Ce, are lower in type-II basalts, and show no correlation with Li/Yb. The higher values of sediment-melt indicators, e.g. Th/Yb and La/Sm, in type-II basalts than those in type-I basalts thus demonstrate that origin of the elevated Li content derived from the subducted materials was sediments. In contrast with the significant differences in other geochemical data between type-I and type-II basalts, Li isotopic compositions in both types are consistent (d7Li = +2.1 - +2.9). This suggests the subducted sediments carried Li isotopic ratios similar to the previous enriched mantle beneath the middle Okinawa Trough. In summary, subducted sediments play a critical role in the lithium cycle, and this subduction component retained in mantle underneath the Ryukyu arc-trench system after subduction, is characterized by relatively higher Li concentration and mantle-like Li isotopic ratio. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study.Objective: The goal of the study was to investigate the significance of a change in latency in monitoring of transcranial muscle-action potential (Tc-MsEP) waveforms.Summary Of Background Data: Tc-MsEP has become a common approach in spine surgery due to its sensitivity and importance in motor function. Many reports have defined the alarm point of Tc-MsEP waveform as a particular decrease in amplitude, but evaluation of the waveform latency has not attracted as much attention.Methods: The subjects were 70 patients who underwent spine surgery using intraoperative Tc-MsEP monitoring. The peak latency was defined as the period from stimulation until the waveform amplitude reached its peak. Relationships with postoperative paralysis were examined separately for latency delays of 5% or more and 10% or more, and in combination with a decrease in amplitude of 70% or more from baseline.Results: Acceptable baseline Tc-MsEP responses were obtained from 1225 of 1372 muscles in the extremities (89.3%). Seven of the 70 patients (10%) had postoperative paralysis. A decrease in intraoperative amplitude of 70% or more from baseline occurred in 25 cases, with sensitivity 100%, specificity 71%, false positive rate 29%, and positive predictive value (PPV) 28% for prediction of postoperative paralysis. Compared to baseline, 15 cases had a latency delay of 5% or more, which gave a sensitivity of 100%, specificity of 87%, false positive rate of 0%, and PPV 47%, and 8 cases had a delay of 10% or more, which gave a sensitivity of 86%, specificity of 97%, false positive rate of 3%, and PPV 75%. A combination of a decrease in amplitude of 70% or more from baseline and a delay in latency of 10% or more from baseline had a sensitivity of 86%, specificity of 98%, and a false positive rate of 2%, and PPV 86%.Conclusion: Combined use of latency and amplitude could lead to reduction of false positives and increase of PPV in Br(E)-MsEP monitoring.Level Of Evidence: 3. [ABSTRACT FROM AUTHOR]

Purpose: Posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) can have complications that require reoperation. The goal of the study was to identify risk factors for reoperation within 2 years after PLIF/TLIF.Methods: A retrospective analysis of a prospective multicenter database was performed for patients who underwent PLIF/TLIF. A total of 1363 patients (689 males and 674 females) were identified, with an average age of 65.9 years old. Comorbidities, perioperative ASA grade, and operative factors were compared between patients with and without reoperation. Risk factors for reoperation were identified in multivariate logistic analysis.Results: There were 38 reoperations within 2 years after PLIF/TLIF (2.8%). The original surgical procedures were open PLIF (n = 26), open TLIF (n = 10), and minimally invasive surgery (n = 2). Reoperation was due to adjacent segment degeneration (ASD) (n = 10), surgical site infection (SSI) (n = 9), screw misplacement (n = 6), postoperative epidural hematoma (n = 6), pseudoarthrosis (n = 4), and cage protrusion (n = 3). Number of levels fused and dural tear were significantly associated with reoperation. In analysis of complications requiring reoperation, SSI was related to diabetes mellitus and dural tear, and postoperative epidural hematoma was related to fusion of two or more levels, EBL, and operation time. In multivariate logistic regression, fusion of two or more levels (HR 2.19) was significantly associated with reoperation.Conclusion: Surgical invasiveness, as reflected by number of fused levels, operation time, EBL and dural tear, was associated with reoperation. Fusion of two or more levels is a strong risk factor for reoperation within 2 years after initial PLIF/TLIF. These slides can be retrieved under Electronic Supplementary Material. [ABSTRACT FROM AUTHOR]

• The source of nitrate pollution was studied in subsurface dammed limestone aquifers. • N and O isotopic tracers of nitrate were applied for identifying pollution source. • Solvable fractions of farmland soils were extracted and measured for isotope ratios. • Soil samples are useful as reference materials for precise source identification. • Updated knowledge on the pollution source was proposed for the studied aquifers. Nitrate contamination of groundwater due to improper management of fertilizer application and controls during agricultural activities is an escalating worldwide issue. Numerous studies have reported similar contamination in the Ryukyu limestone aquifer in the southern part of Okinawa Island. The study area has a unique setting where the subsurface dams hold the groundwater behind their cut-off walls, probably holding contaminated waters. This study provides updated insights on the source of contamination using stable N and O isotope ratios of dissolved nitrate (ẟ15N NO3 and ẟ18O NO3) in the aquifer waters. To propose a better reference in the source fingerprinting assessment, a special emphasis was placed on the isotopic comparison between the fertilizers and farmland soils where the respective fertilizers were applied. A total of 176 groundwater samples were collected from several spatial and monthly sampling campaigns for the purpose of source determination. Our isotopic comparison detected the enrichment of 15N of nitrate-nitrogen in the soil samples after the application of both chemical fertilizers and manure due to nitrification and volatilization. Unlike results from previous studies, the ẟ15N NO3 compositions of most groundwater samples did not fall into the range of soils mainly controlled by chemical fertilizers (from +3‰ to +5‰), but were comparable to the soils affected by mixed fertilizers including both chemical fertilizers and manure (from +7‰ to +9‰). The soils beneath untreated manure storage sites characterized by the highest ẟ15N NO3 values (from +18‰ to +20‰) affected some groundwater, which shows an even higher value (> +9‰). The contaminated waters tend to be gathered close to the subsurface dams and this tendency did not differ between two subsurface dam settings, Komesu and Giza. However, due to more impact from manure storage sites, the groundwater in the Komesu area tends to show slightly higher δ15N NO3 values than those in the Giza area. Our study demonstrated the usefulness of soil samples for precise isotopic source identification in farmland areas. [ABSTRACT FROM AUTHOR]

Sediments are actively subducted in virtually every arc worldwide. However, quantifying their contributions to arc lavas and thereby establishing budgets of how sediments participate in slab-mantle interaction is challenging. In this contribution we use thallium (Tl) abundances and isotopic compositions of lavas from the Ryukyu arc (including south Kyushu) and its back-arc basin, Okinawa Trough, to investigate the influence of sediments from arc to back-arc. We also present extensive geochemical data for sediments and altered oceanic crust (AOC) outboard of the northern (DSDP Sites 296, 442B, 443 and 444) and central (DSDP Sites 294 and 295) part of the Ryukyu arc. The Tl isotopic compositions of sediments change systematically from lighter outboard of northern Ryukyu arc to heavier outboard of central Ryukyu arc. The feature reflects the dominance of terrigenous material and pelagic sedimentation outboard of the northern and central Ryukyu arc, respectively. Central and northern sections of Ryukyu arc and Okinawa Trough display larger range of Tl isotopic variation than southern section, which is consistent with more pelagic provenance for sediments outboard of central and northern Ryukyu arcs than that of expected sediments outboard of southern Ryukyu arc. Identical Tl, Sr, Nd and Pb isotope variations are found when comparing arc and back arc lavas, which indicates that sediments fluxes also account for the Tl isotopic variations in the Okinawa Trough lavas. Two-end-member mixing models of Tl with Pb, Sr and Nd isotopes require sediment inputs of< 1%, 0.1–1% and 0.3–2% by weight to the depleted mantle source to account for all these isotopic compositions of lavas from northern, central and southern portion of the Ryukyu arc and Okinawa Trough. Bulk mixing between mantle and sediment end members predict very similar sediment fluxes when using Tl, Sr, Nd and Pb isotopes, which indicates that fractionation of these elements must have happened after mixing between mantle and sediments. This conclusion is corroborated by model calculations of mixing between sediment melts with fractionated Sr/Nd ratios and mantle wedge, which show that no arc lava plot on such mixing lines. Thus bulk sediment mixing, rather than sediment melt, is required for the generation of the lavas from the Ryukyu arc and Okinawa Trough. The requirement of bulk sediment mixing occurring before trace element fractionation in the sub-arc mantle is consistent with models where mélange layers form at the top of the slab and are the principle source material for arc lavas. In addition, the fact that sediment components observed in the Ryukyu arc and Okinawa Trough lavas are similar, suggests that transport of mélange material to the source regions of the arc and back arc is equally efficient. This feature is most readily explained if mélange material is transported from the slab as diapirs. [ABSTRACT FROM AUTHOR]

People living in the Great Rift Valley in East Africa suffer from fluorosis resulting from their consumption of groundwater. This paper shows that geogenic fluoride contamination in a natural water system has changed in the last two decades in the Mt. Meru slope area of northern Tanzania based on water quality, dating of the residence time, and stable isotopes of groundwater. The results demonstrate that 1) the average recharge altitude of groundwater with a high geogenic fluoride concentration is estimated to range from 1900 m to 3000 m on the southern slope of Mt. Meru, and the fluoride concentration tends to increase with an increase in the recharge altitude, 2) the fluoride concentration increases with increasing groundwater residence time for groundwater with a residence time of 20 years or longer, suggesting that water-rock interaction processes (weathering, dissolution, and ion exchange), which depend on the contact time between the volcanic aquifer and groundwater, have predominated for approximately 20 years or longer, and 3) the mixing of aerobic young water and old groundwater has been active for approximately 20 years, and the fluoride concentration is increasing in some shallower well waters. The mixing of fluoride-contaminated groundwater with aerobic water infiltrating the aquifer through pumping groundwater in the last two decades may increase the spread of groundwater contaminated with fluoride due to increased water demand caused by rapid population growth, and urbanization, industrial growth, and the expansion of irrigated agriculture. • People living in the Mt. Meru slope area in East Africa suffer from fluorosis. • The mixing of aerobic young water and old groundwater has been active for 20 years. • Groundwater fluoride contamination has changed in the last two decades. • Pumping of groundwater may increase the spread of the groundwater contamination. [ABSTRACT FROM AUTHOR]

Compositional changes, dehydration reactions and fluid flow in subducted sediments influence seismogenesis and arc magmatism in subduction zones. To identify fluid flow and water–rock interaction processes in the western Nankai Trough subduction zone (SW Japan) we analyzed boron concentration and boron isotope composition (δ 11 B) of pore fluids sampled across the subduction zone forearc from depths of up to ∼922 m below seafloor during four Integrated Ocean Drilling Program (IODP) Expeditions. The major structural regimes that were sampled by coring include: (1) sedimentary inputs, (2) the frontal thrust zone, (3) the megasplay fault zone, and (4) the forearc basin. From mass balance consideration we find that consumption of boron (B) by ash alteration and desorption of B from the solid phase, mediated by organic matter degradation, produces a net decrease in B concentrations with depth down to ∼120 μM and variable δ 11 B values in the range of ∼+20‰ and +49‰. Interstitial water in sediments on the incoming oceanic plate are influenced by more efficient mobilization of exchangeable B from the solid phase due to higher temperatures and alteration of the oceanic crust that acts as a sink for 10 B. At the tip of the megasplay fault zone, elevated B concentration and B isotopic composition suggest that underthrust coarse-grained slope sediments provide a pathway for fluids out of the upper (<2 km) accretionary prism. Silt and sand layers in the underthrust section of the downgoing plate favor fluid escape in seaward direction from depths equivalent to the temperature range of 60–150 °C. At both locations the δ 11 B signature evolves during updip migration through re-adsorption. Mass balance considerations suggest a shallower fluid source depth compared to pore fluids sampled previously near the décollement zone along the central portion of the Nankai margin. [ABSTRACT FROM AUTHOR]

New isotopic and trace element data presented here imply a temporal change in magma sources and thermal conditions beneath the northern Fossa Magna of NE Japan from the Miocene to the Pliocene. Less radiogenic 176 Hf/ 177 Hf and 143 Nd/ 144 Nd, high Zr/Hf, and little or no Hf anomaly characterize the Early Miocene volcanism in the northern Fossa Magna region. The mantle wedge consisted of chemically heterogeneous mantle source. Based on out isotope proxies, we propose that during the onset of subduction, influx of hot asthenospheric mantle provided sufficient heat to partially melt newly subducting sediment. Geochemical modeling demonstrates that slab-derived melt mixed with mantle wedge produces the observed isotopic and trace elemental characteristics. In the Middle Miocene, the injection of hot and depleted asthenospheric material replaced the mantle beneath the northern Fossa Magna region of NE Japan. This caused the isotopic signature of the rocks to change from enriched to depleted. Then, the mantle wedge was gradually cooled during the Middle Miocene to the Pliocene with back-arc opening ending in the Late Miocene. Slab surface temperatures were still high enough for sediments to melt but not too high (<∼780 °C) to lose zircon as a residual phase. The Late Miocene and Pliocene volcanism at the post stage of the back-arc opening is best explained by a partial melting of subducted metasediment saturated with trace quantities of zircon and rutile. [ABSTRACT FROM AUTHOR]

During the Integrated Ocean Drilling Program ( IODP) Expedition 338, several methods were tested for the extraction of interstitial water in consolidated, low-porosity deep-sea sediments from Site C0002 in the Kumano Basin. On the basis of those tests, we propose a modified ground rock interstitial normative determination ( GRIND) method of extraction of interstitial water. In separate runs of the new method, sediment samples were ground in a ball mill with either ultrapure water or a solution of HNO3. The interstitial water was then extracted with a conventional squeezer. Sufficient solution was extracted by this method to analyse most major and a few minor components of interstitial water that were comparable to those previously reported for samples extracted by the conventional squeezing method. The new method requires much smaller amounts of sediment than that of the conventional method and will be useful for analysis of samples recovered during super-deep drilling programmes. [ABSTRACT FROM AUTHOR]

Background: Postoperative pancreatitis has primarily been reported as a complication of abdominal surgery, but there are some case reports of postoperative pancreatitis after spinal surgery. The objective of this study was to investigate a case series of hyperamylasemia and pancreatitis following posterior spinal surgery.Methods: The serum amylase level was measured following posterior spinal surgery in the prone position. Patients were divided into groups with a normal serum amylase level (0-125 IU/L) and with hyperamylasemia (>125 IU/L), based on the upper limit of normal of 125 IU/L in our institution. Relationships among preoperative factors, perioperative factors, and the serum amylase level were investigated.Results: Hyperamylasemia (serum amylase >125 IU/L) following posterior spinal surgery was found in 92 cases (35 %). Among perioperative factors, intraoperative estimated blood loss (EBL) and operating time were significantly higher in patients with high serum amylase than in patients with normal serum amylase (P < 0.01). In a multivariate regression model, intraoperative EBL (OR 1.001, 95 % CI 1.000-1.002; P = 0.001) and operation time (OR 1.006, 95 % CI 1.003-1.009; P = 0.006) were significantly associated with postoperative pancreatitis. Serum amylase levels of ≥ 5 times the upper limit of normal were found in six cases. Five of these cases were asymptomatic and one was caused by severe pancreatitis.Conclusions: In our case series, intraoperative blood loss caused a rise in the serum amylase level following posterior spinal surgery. Thus, this level should be carefully monitored after spinal surgery with significant blood loss. Clinical symptoms of pancreatitis, such as abdominal pain and vomiting, should also be monitored following spinal surgery. [ABSTRACT FROM AUTHOR]

The Sawlava ophiolite is situated on the Iran–Iraq border within the Walash-Kermanshah ophiolitic belt and represents remnants of the Cenozoic southern Neo-Tethys Ocean, which was located between the Arabian plate and the Sanandaj–Sirjan zone. It contains a complete ophiolitic sequence started from harzburgites with foliated/discordant dunites, gabbroic bodies, a dyke complex, and pillow as well as massive basaltic lavas. The whole-rock and mineral chemistry of the Sawlava peridotites suggest that they are a mantle residuum after ca. 20–30% partial melting and melt extraction in the suprasubduction zone (SSZ) setting. The volcanic rocks generally range from island arc tholeiite to calc-alkaline affinities. Whole-rock chemistry indicates that volcanic units have compositions akin to depleted- and enriched-types mid-ocean ridge basalts (E -MORB). Layered- and isotropic gabbros show geochemical affinity similar to the normal mid-ocean ridge basalt (N-MORB) and E -MORB compositions, respectively. Their llight rare earth elements (LREE) observed in both N-MORB-like and E-MORB-like rocks, define two main basic geochemical types (LREE-enriched and LREE-depleted), suggesting several magmatic pulses from different mantle compositions that reveal mantle evolution and heterogeneity across the study area. Basaltic lavas weakly depleted in LREE show relatively flat REE patterns and (La/Yb) N values of 0.77 to 1.24, whereas LREE-enriched rocks have a (La/Yb) N mean values of 1.7, and lack an Eu anomaly. These subgroups of basaltic rocks show different extrusion ages – Paleocene–Eocene (59–50 Ma) and Oligocene (29 Ma), respectively. Petrogenetic modeling shows that mafic N- and E -MORB type rocks of Sawlava, which have (La/Yb) N = 0.97 and 1.7 and (Dy/Yb) N = 1.13 and 1.1, respectively, formed due to partial melting of a mantle source less enriched in LREE than an garnet lherzolite ((La/Yb) N = 0.88 and (Dy/Yb) N = 0.94) source or, alternatively, from very low degree (<2%) partial melting of a spinel-bearing DMM. The La/Yb–Dy/Yb systematics of these rocks are interpreted to be compatible with ~2 to 10% and ~ 20% of partial melting of a garnet bearing spinel lherzolite source for the N- and E -MORB type rocks, respectively. The geochemical data and results reveal that magmatic-originated rocks from both Paleocene-Eocene and Oligocene lavas seem to be less heterogeneous compared with the mantle sources of the Walash-Kermanshah ophiolites, likely due to different slab-fluid components and variations of partial melting degrees. The studied volcanic rocks therefore possibly record chemical heterogeneity due to magmatic activity at an oceanic spreading center alongside slab rollback and back-arc extension at the Eurasian continental margin. • Evidence of a two phases Cenozoic volcanism along Iran-Iraq border. • Sawlava ophiolites consist of the Paleocene-Eocene immature back-arc and the Oligocene back-arc basalts. • Chemical heterogeneity at an oceanic spreading center alongside slab retreat and back-arc extension has occurred. [ABSTRACT FROM AUTHOR]

Seasonally resolved records of carbon and oxygen isotopic composition (δ18 O) in fossil shells of giant clams ( Tridacnidae) recovered from the Kogachibaru Shell Mound (26°26′ N, 127°49′ E) and the Second Aragusuku- Shichabaru Ruin (26°18′ N, 127°46′ E) in Okinawa-jima, southwestern Japan, were investigated to reconstruct subtropical coral reef environments of the past. The samples, mainly composed of aragonite shells with limited amounts of diagenetically-altered calcite cements, were selected for geochemical analyses. The radiocarbon dating of the samples for stable isotope analyses yields about 4000 yr cal. BP for the Kogachibaru Shell Mound and about 1900-1700 yr cal. BP for the Second Aragusuku- Shichabaru Ruin, respectively, that correspond to the early and middle Shell Mound periods in Okinawa-jima. These show good agreement with the respective ages inferred from excavation. The shell δ18 O values roughly show seasonal variations, coincident with the occurrence of annual growth bands. Applying corrections for the effect of diagenetic alteration, the averages of annual, summer, and winter δ18 O values of fossil shells were significantly lower (by 0.1-0.7‰) than those of aragonite theoretically precipitated in present-day coral reef water of Okinawa-jima. These results demonstrate that annual mean seawater temperature and salinity at the sites where the Tridacnida spp. lived were about 1-3°C higher and/or about 1-2 lower than at present. This variation cannot be fully explained by global climate change, sea level change, and topographic growth of coral reef. Therefore, it is likely that the giant clams lived in extremely small and/or closed coral-reef lagoons with less water circulation where seawater is highly susceptible to insolation-induced temperature increase and input of fresh water; the effect could be enhanced by the fisheries lifestyle that stonewalling would be constructed at shallow waters through the use of tidal variation during the early and middle Shell Mound period in Okinawa-jima. [ABSTRACT FROM AUTHOR]