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Although submarine landslides have been studied for decades, a persistent challenge is the integration of diverse geoscientific datasets to characterize failure processes. We present a core‐log‐seismic integration study of the Tuaheni Landslide Complex to investigate intact sediments beneath the undeformed seafloor as well as post‐failure landslide deposits. Beneath the undeformed seafloor are coherent reflections underlain by a weakly‐reflective and chaotic seismic unit. This chaotic unit is characterized by variable shear strength that correlates with density fluctuations. The basal shear zone of the Tuaheni landslide likely exploited one (or more) of the low shear strength intervals. Within the landslide deposits is a widespread "Intra‐debris Reflector", previously interpreted as the landslide's basal shear zone. This reflector is a subtle impedance drop around the boundary between upper and lower landslide units. However, there is no pronounced shear strength change across this horizon. Rather, there is a pronounced reduction in shear strength ∼10–15 m above the Intra‐debris Reflector that presumably represents an induced weak layer that developed during failure. Free gas accumulates beneath some regions of the landslide and is widespread deeper in the sedimentary sequence, suggesting that free gas may have played a role in pre‐conditioning the slope to failure. Additional pre‐conditioning or failure triggers could have been seismic shaking and associated transient fluid pressure. Our study underscores the importance of detailed core‐log‐seismic integration approaches for investigating basal shear zone development in submarine landslides. Plain Language Summary: Submarine landslides move enormous amounts of sediment across the seafloor and have the potential to generate damaging tsunamis. To understand how submarine landslides develop, we need to be able to image and sample beneath the seafloor in regions where landslides have occurred. To image beneath the seafloor we generate sound waves in the ocean and record reflections from those waves, enabling us to produce "seismic images" of sediment layers and structures beneath the seafloor. We then use scientific drilling to sample the sediment layers and measure physical properties. In this study, we combine seismic images and drilling results to investigate a submarine landslide east of New Zealand's North Island. Drilling next to the landslide revealed a ∼25 m‐thick layer of sediment (from ∼75–95 m below the seafloor) that has strong variations in sediment strength and density. We infer that intervals of relatively low strength within this layer developed into the main sliding surface of the landslide. Additionally, results from within the landslide suggest that the process of landslide emplacement has induced a zone of weak sediments closer to the seafloor. Our study demonstrates how combining seismic images and drilling data helps to understand submarine landslide processes. Key Points: We integrate scientific drilling data with seismic reflection data to investigate the submarine Tuaheni Landslide ComplexBasal shear zone of the landslide likely exploited a relatively low shear strength interval within an older (buried) mass transport depositLandslide emplacement seems to have induced an additional weak zone that is shallower than the interpreted base of the landslide deposit [ABSTRACT FROM AUTHOR]

Abstract: A transect of seafloor heat probe measurements on the Hikurangi Margin shows a significant increase of thermal gradients upslope of the updip limit of gas hydrate stability at the seafloor. We interpret these anomalously high thermal gradients as evidence for a fluid pulse leading to advective heat flux, while endothermic cooling from gas hydrate dissociation depresses temperatures in the hydrate stability field. Previous studies predict a seamount on the subducting Pacific Plate to cause significant overpressure beneath our study area, which may be the source of the fluid pulse. Double‐bottom simulating reflections are present in our study area and likely caused by uplift based on gas hydrate phase boundary considerations, although we cannot exclude a thermogenic origin. We suggest that uplift may be associated with the leading edge of the subducting seamount. Our results provide further evidence for the transient nature of fluid expulsion in subduction zones. [ABSTRACT FROM AUTHOR]

Despite intense research by both academia and industry, the parameters controlling slope stability at continental margins are often speculated upon. Lack of core recovery and age control on failed sediments prevent the assessment of failure timing/frequency and the role of prefailure architecture as shaped by paleoenvironmental changes. This study uses an integrated chronological framework from two boreholes and complementary ultrahigh-resolution acoustic profiling in order to assess (1) the frequency of submarine landsliding at the continental margin of NE Gela Basin and (2) the associated mechanisms of failure. Accurate age control was achieved through absolute radiocarbon dating and indirect dating relying on isotope stratigraphic and micropaleontological reconstructions. A total of nine major slope failure events have been recognized that occurred within the last 87 kyr (~10 kyr return frequency), though there is evidence for additional syndepositional, small-scaled transport processes of lower volume. Preferential failure involves translational movement of mudflows along subhorizontal surfaces that are induced by sedimentological changes relating to prefailure stratal architecture. Along with sequence-stratigraphic boundaries reflecting paleoenvironmental fluctuations, recovered core material suggests that intercalated volcaniclastic layers are key to the basal confinement and lateral movement of these events in the study area. Another major predisposing factor is given by rapid loading of fine-grained homogenous strata and successive generation of excess pore pressure, as expressed by several fluid escape structures. Recurrent failure, however, requires repeated generation of favorable conditions, and seismic activity, though low if compared to many other Mediterranean settings, is shown to represent a legitimate trigger mechanism. [ABSTRACT FROM AUTHOR]

Background and purpose Some 3%−10% of patients with multiple sclerosis ( MS) experience disease onset before the age of 18 years ('early' onset MS, EOMS). Optical coherence tomography is a non-invasive method to measure retinal nerve fibre layer thickness ( RNFLT) and total macular volume ( TMV) and may be useful to differentiate axonal and neuronal damage in the retina of patients with a history of EOMS. Here RNFLT and TMV in EOMS patients after a mean disease duration of 11.6 years were compared with patients with age- or disease-duration-matched later onset MS ( LOMS) and healthy controls ( HCs). Methods In this observational cross-sectional study at two German academic MS centres, RNFLT and TMV were measured by spectral-domain optical coherence tomography in 32 HCs, 36 EOMS (mean age at onset 15.5 ± 2.0 years) and 58 LOMS patients. Results In comparison with HCs, EOMS patients displayed a significant reduction of RNFLT and TMV independently of a history of optic neuritis. In particular, RNFLT loss in EOMS was similar to that in LOMS and TMV loss was slightly higher compared with disease-duration-matched LOMS. In a generalized estimating model, the EOMS group also displayed a similar correlation between disease duration and RNFLT or TMV loss to LOMS patients. Conclusions These data argue for a significant amount of axonal and neuronal damage in the retina of EOMS patients and may provide a structural basis for the observation that EOMS patients reach states of irreversible disability at a younger age than patients with LOMS. [ABSTRACT FROM AUTHOR]

In order to stabilize the intraruminal pH, bicarbonate secretion by the ruminal epithelium seems to be an important prerequisite. The present study therefore focussed on the characterization of bicarbonate exporting systems in ruminal epithelial cells. Intracellular pH (pHi) was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2,7-bis(carboxyethyl)-5(6′)-carboxyfluorescein acetomethyl ester. Switching from CO2/HCO-buffered to HEPES-buffered solution caused a rapid intracellular alkalinization followed by a counter-regulation towards initial pHi. The recovery of pHi was dependent upon extracellular chloride, but independent of extracellular sodium. Adding 500 μM H2DIDS significantly reduced the increase of pHi. For further characterization of the bicarbonate exporting systems, we tested the ability to reverse the direction from HCO export to import in the absence of sodium and chloride. Under sodium and chloride-free conditions, counter-regulation after CO2-induced pHi decrease did not differ from pHi recovery in the presence of sodium and chloride. Existence of bicarbonate exporting systems in cultured ruminal epithelial cells and intact ruminal epithelium was verified by reverse transcription polymerase chain reaction (RT-PCR). Using RT-PCR and subsequent sequencing, expression of mRNA encoding for AE2, DRA and PAT1 could be found. Bicarbonate exporting systems could therefore be detected both on the functional and structural level. [ABSTRACT FROM AUTHOR]

The present study aimed to identify the HCO3--dependent mechanisms contributing to the homeostasis of the intracellular pH (pHi) in ruminal epithelial cells of sheep. Therefore, pHi was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2′,7′-bis(carboxyethyl)-5(6′)-carboxyfluorescein acetoxymethyl ester. Switching from a HEPES-buffered to a CO2/HCO3--buffered solution caused a rapid intracellular acidification followed by a counter-regulation towards alkaline levels. The counter-regulation was totally dependent upon extracellular Na+, but independent of intracellular Cl-. Adding 30 μM EIPA to the solutions did not affect the pHi counter-regulation following the acidification. Presence of 500 M H2DIDS inhibited the counter-regulation of pHi by 67%. These results pointed to a Na+–HCO3--cotransporter (NBC) as the main pHi regulatory mechanism in the presence of HCO3-. Existence of an NBC in both cultured ruminal epithelial cells and intact ruminal epithelium was verified by reverse transcription polymerase chain reaction (RT-PCR) studies. RT-PCR yielded a band of the expected molecular size of 333 bp in both cultured cells and intact epithelium. The mRNA sequences were identical and shared a homology of 62% with human kidney NBC (Genebank accession number AF007216), of 66% with rat kidney NBC (AF004017) and of 65% with mouse duodenal NBC (AF141934). [ABSTRACT FROM AUTHOR]

XMEL is a monoclonal antibody raised against part of the extra-cellular domain of the putative tyrosine kinase receptor protein implicated in the pathogenesis of melanoma formation in the Xi-phophorus fish melanoma model. Our objective in this study was to determine the diagnostic and prognostic utility of XMEL for human melanoma. Formalin-fixed tissue from 82 melanomas, 42 carcinomas, 23 neural tumors, 12 lymphomas and 12 sarcomas were immunostained with XMEL and compared with a widely used melanoma antibody, HMB-45. The sensitivity of HMB-45 (83.1%) was similar to that of XMEL (79.8%). XMEL detected 7 melanomas that were HMB-45 negative. Specificity for detection of melanoma was greater with HMB-45 (95.5%) as compared to XMEL (80.9%). Of interest, a11 4 prostatic adeno carcinomas were XMEL positive. These data suggest that XMEL is as sensitive but not as specific as HMB-45 in the detection of cutaneous melanoma but may serve as an ancillary antibody to improve diagnostic yield. The consistent positivity of XMEL in melanoma lends support to the hypothesis that the detected protein plays a role in melanoma pathogenesis. XMEL reactivity is not an independent prognosticator of death from melanoma in 37 melanomas from patients with at least 10 years' follow-up. These data and the fact that XMEL shows variable reactivity with metastatic melanomas but almost 100% reactivity with the primary melanomas suggest that the antigen recognized by the XMEL antibody may be important in the early stages of melanoma progression. This is supported by our earlier observation that XMEL is reactive with dysplastic nevi, a precursor of malignant melanoma. [ABSTRACT FROM AUTHOR]

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The progression of idiopathic dilated cardiomyopathy (IDC) is governed by factors that remain obscure. The disease pathway toward cell degeneration or death results in irreversible myocyte change including nuclear cytometric alterations which may be evaluable and ultimately correlated with other measures of disease evolution.Using a novel image cytometry system, we analysed differences in ventricular myocyte nuclear morphology and DNA content and distribution in right and left ventricular free wall myocardium and in ventricular septal myocardium from 11 normal and 13 IDC human autopsy hearts.Nine morphological features of IDC myocyte nuclei differed significantly (P > 0.001) from normal. These were used to establish a classification matrix and cytometry-based assessment and allowed correct categorization of left and right ventricular and ventricular septal myocyte nuclei in concordance with their respective pathological diagnosis {i.e. normal or IDC) 71%, 81% and 77% of the time. Additionally, four photometric features were significantly different (P> 0.005) in IDC versus normal hearts, as were three discrete texture features (P > 0.001).Thus, the spectrum of myocyte nuclei seen in IDC have highly characteristic and measurable morphologic, photometric and texture features. Our findings indicate the potential value of cytometry in the classification of myocytes with regards to a disease continuum and suggest its applicability in both clinical and experimental studies [ABSTRACT FROM PUBLISHER]

Aminofunctional siloxanes are important auxiliary chemicals for softening in a broad class of finishing applications. They provide "supersoft" hand in premium grade fabrics in addition to other important benefits. Their chief drawback is yellowing with loss of water absorbency. The structure activity relationship between the arrangement of pendant aminofunctional side chains and important finish responses such as whiteness, hand, water absorbency and soil release is explored. Surprisingly, dramatic effects are observed which suggest that optimization of the structure of the aminofunctional side chain could lead to substantial finish Improvement. [ABSTRACT FROM AUTHOR]