Major ENE Research Articles

Extranodal extension in oral squamous cell carcinoma: clinical and histopathological analysis

ObjectiveExtranodal extension (ENE) is an important prognostic factor in oral squamous cell carcinoma (OSCC). This study aimed to evaluate the clinical significance of stratifying minor or major ENE in OSCC. Study DesignThis retrospective cohort study included 75 patients who had undergone neck dissection for OSCC and were classified as pN+. ENE was measured using hematoxylin-eosin-stained specimens and stratified into major (ENEma, >2 mm) and minor (ENEmi, ≤2 mm) by distance. Their association with survival, locoregional relapse, and distant metastases were assessed. ResultsOf 49 patients with pathological ENE, 23 had ENEmi and 26 had ENEma. The 5-year overall survival (OS) was 38%, 66%, and 76% in the ENEma, ENEmi, and no ENE groups, respectively. Compared with no ENE, ENEma was associated with significantly decreased 5-year cumulative OS and disease-specific survival. ENEma was a risk factor for decreased OS (HR: 2.54, 95% CI: 1.04–6.18, P =.040) in the multivariable Cox regression analysis, and was associated with distant metastasis. ConclusionIn patients with OSCC, ENEma is associated with a significantly poorer prognosis; therefore stratifying ENE is clinically relevant. ENEma may increase the risk of distant metastasis; therefore, new treatment modalities that contribute to distant metastasis control are required.

Mapping and analysis of structural lineaments using SRTM radar data and Landsat-8 OLI image: an example from the Telouet–Tighza area, Marrakech High Atlas, Morocco

This study provides the first evaluation of the potential of both the Landsat-8 Operational Land Imager (OLI) sensor images and the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) data for automated lineament extraction in the south side of the Marrakech High Atlas (Telouet–Tighza area). After image corrections, enhancement methods such as principal component analysis, band composite (BC), and directional filtering were adopted to create new images that provided high visibility of linear structures. The new Landsat BC image used in this study was selected based on the calculation of the optimum index factor and correlation index. In addition to the Landsat image, the SRTM DEM was used to detect structural lineaments in the area by generating shaded relief images. Multisource data, such as band ratio image, geological maps, and fieldwork, were used to eliminate the nongeological lineaments extracted. The results indicate that an automated method was applied successfully for lineament mapping in this area, by detailing the main tectonic faults. Moreover, new lineaments are identified and are validated by fieldwork. Structural lineaments extracted show compatibility in their direction, length, distribution, and density with the tectonic evolution of the study area. A total of 2945 lineaments were extracted with major ENE–WSW and predominant E–W directions. The new structural map shows more structural information compared with the geological map of this area and exemplifies the performance of Landsat-8 OLI bands and SRTM data in this kind of study.

Influence of multi-trend major fault reactivation during multiphase rifting: Beier Depression, Hailar Basin, NE China

AbstractComplex fault patterns associated with rift development in the Hailar Basin were largely influenced by the Mongolia–Okhotsk Ocean and Palaeo-Pacific tectonic regimes during the Late Jurassic to Early Cretaceous periods. Based on 3D seismic data from the Beier Depression in the Hailar Basin, we characterized the reactivation history of multi-trend major faults and examined the evolution of the Beier Depression during the Early Cretaceous period. NE–SW-, NW–SE- and ENE–WSW-oriented major faults originated from strike-slip-associated structures that were pre-existing fabrics and then were reactivated and propagated upward under extensional regimes in the Late Jurassic. During the syn-rift stage (K1t–K1n), the Hailar Basin was in a NNW–SSE- to NW–SE-oriented extensional setting, and major faults of all orientations were active. There was tectonic quiescence (K1n1L) between the syn-rift stages (a rifting transition stage). The short compression stage after the syn-rift stage caused regional compressional deformation. During the post-rift stage (K1d–K1y), the extension direction rotated to an E–W orientation, and a new population of N–S-trending faults formed together with the reactivation of NE–SW- and ENE–WSW-trending major faults. Structural analysis shows that the major ENE–WSW-trending major faults were polycyclic growth faults reactivated via an upward propagation mode and that the NE–SW-trending faults were dip linkage faults reactivated via a dip linkage mode. The reactivation intensity of the NE–SW-trending major faults was stronger than that of the ENE–WSW-trending major faults. These results demonstrate the differences in the evolution of the different trending faults in the same tectonic regime, and the complexity of the final fault patterns in the Beier Depression was produced by differences in the reactivation of major faults. The originate interpretation of the multi-trend major faults in the Hailar Basin provides new insights into fault generation, and the classification of fault growth also has useful implications for future research on multiphase rifts.

Radiologic-pathologic correlation of major versus minor extranodal extension in oral cavity cancer.

To evaluate the diagnostic performance of radiologic extranodal extension (rENE) in predicting major (>2 mm) and minor (≤2 mm) pathologic ENE (pENE). All oral cavity squamous cell carcinoma patients who underwent neck dissection with pathological nodal disease (pN+) between 2010 and 2015 were reviewed. Preoperative computed tomography and/or magnetic resonance imaging were reviewed by two head and neck neuroradiologists. Three hundred and thirty-four patients were included. The sensitivity and specificity of rENE were 37% [95% CI 29-44] and 98% [95% CI 96-100], respectively. Sensitivity for pENE improved in the subset of patients with major ENE (48% [95% CI 38-57]). The presence of rENE was associated with inferior 3-year overall survival: 26% [95% CI 17-41] versus 60% [95% CI 54-67]. This large cohort study demonstrates high specificity, but low sensitivity for preoperative imaging in the detection of pENE in OCSCC. Patients with rENE demonstrated poor OS. pENE in the absence of rENE is still an adverse risk factor.

The fracture system and the melt emplacement beneath the Deception Island active volcano, South Shetland Islands, Antarctica

AbstractA new magnetotelluric (MT) survey, along with new topographic parametric sonar (TOPAS) profiles and geological field observations, were carried out on the Deception Island active volcano. 3-D resistivity models reveal an ENE–WSW elongated conductor located at a depth between two and ten kilometres beneath the south-eastern part of the island, which we interpret as a combination of partial melt and hot fluids. The emplacement of the melt in the upper crust occurs along the ENE–WSW oriented, SSE dipping regional normal fault zone, which facilitates melt intrusion at shallower levels with volcanic eruptions and associated seismicity. Most of the onshore and offshore volcanic rocks are deformed by high-angle normal and sub-vertical faults with dominant dip-slip kinematics, distributed in sets roughly parallel and orthogonal to the major ENE–WSW regional tectonic trends. Faults development is related to perturbations of the regional stress field associated with magma chamber overpressure and deflation in a regional setting dominated by NW–SE to NNW–SSE extension.

Extensive Early Neoproterozoic high-grade metamorphism in North Chotanagpur Gneissic Complex of the Central Indian Tectonic Zone

The Indian Shield was assembled through a Proterozoic collision between the northern and southern Indian continental blocks along the ENE–WSW Central Indian Tectonic Zone (CITZ). Chemical dating of monazite, xenotime and uraninite, and thermobarometric analysis are carried out to determine the spatial extent and assess the significance of Early Neoproterozoic high-grade metamorphism in the northern sector of the Chotanagpur Gneissic Complex (CGC), a Proterozoic belt of granite and granitic gneiss in the eastern part of CITZ. In northwest CGC, xenotime in granitic gneiss crystallized at 975 ± 67 Ma along foliation that developed at high metamorphic temperatures (788–861 °C). Thus Grenvillian metamorphism in northwest CGC may be correlated with the high-grade Grenvillian metamorphic terranes in northeast and north–central CGC, and similar terrane in central India. In the area northwest of the NE–SW boundary fault of CGC, monazite crystallized at 1697 ± 17 Ma in porphyritic granite that lacks < 1.6 Ga thermal imprint. Thus the Grenvillian metamorphic front did not extend across the boundary of the CGC. Furthermore, the lithological association of granite and country schist/phyllite, and the timing of granite intrusion are similar to those in the Son–Narmada Graben, a major ENE–WSW lineament comprising the northern part of CITZ in central India. Therefore, the graben most probably extends in a northeasterly direction along the NE–SW boundary of the CGC. In the northeastern corner of the CGC, a 768 ± 11 Ma age of uraninite in biotite–gneiss may be related to mid-Neoproterozoic high-grade metamorphism along the eastern margin of the CGC. Pervasive high-grade Grenvillian metamorphism in the entire northern sector of the CGC may be related to a terminal Grenvillian assembly of the Indian Shield in the Rodinia supercontinent.

P and S velocity structures of the Santorini–Coloumbo volcanic system (Aegean Sea, Greece) obtained by non-linear inversion of travel times and its tectonic implications

One of the most prominent tectonic features of the Eastern Mediterranean region is the Hellenic volcanic arc in the Southern Aegean Sea, with the Santorini Island being one of the most active volcanic centers. Recent seismic studies show that the main seismic activity of the Santorini volcanic center is strongly associated with the volcanic processes, as well as with the seismo-tectonic regime of the broader Southern Aegean Sea area. The main cluster of local seismicity is located near the northeastern edge of the Santorini Island, beneath the Coloumbo Reef, which is a submarine volcanic seamount of the Santorini Island volcanic system. The P and S wave velocity structures of the Santorini–Coloumbo volcanic system is studied by inverting travel times of local earthquakes recorded by two independent dense seismic arrays installed in the broader area of Santorini islands during the period of September 2002–September 2005. In particular, 137 local earthquakes with 1600 P phases and 1521 S phases recorded by 25 seismological stations have been selected for the inversion. The inversion technique applied is non-linear, since three-dimensional ray tracing is incorporated. The reliability of the final tomographic results is demonstrated through resolutions tests using synthetic seismic data. The obtained results confirm the strong variations of the P and S wave velocity structures in the area of Santorini–Coloumbo volcanic system, as well as the connection between the tectonic setting of the study area with the magmatic processes taking place beneath the two volcanoes. The tomographic models show that a low-velocity zone extends along the northeastern edge of the Santorini Island, parallel to the “Kameni–Coloumbo” fracture zone (NE–SW direction), which corresponds to the western termination of the major ENE–WSW Santorini–Amorgos Fault Zone. Evidence is presented that this structural lineament corresponds to a tecto-volcanic fracture zone, which probably links the volcanic center of Santorini with the submarine volcano at Coloumbo Reef. Furthermore, the tomographic results show indications that the magmatic chamber beneath the Coloumbo volcanic seamount is located at a depth of 6–7 km in good agreement with recent independent studies in the area, though this feature is not within the resolving power of the employed data set.

Seismicity and active tectonics at Coloumbo Reef (Aegean Sea, Greece): Monitoring an active volcano at Santorini Volcanic Center using a temporary seismic network

The volcanic center of Santorini Island is the most active volcano of the southern Aegean volcanic arc. Α dense seismic array consisting of fourteen portable broadband seismological stations has been deployed in order to monitor and study the seismo-volcanic activity at the broader area of the Santorini volcanic center between March 2003 and September 2003. Additional recordings from a neighbouring larger scale temporary network (CYCNET) were also used for the relocation of more than 240 earthquakes recorded by both arrays. A double-difference relocation technique was used, in order to obtain optimal focal parameters for the best-constrained earthquakes. The results indicate that the seismic activity of the Santorini volcanic center is strongly associated with the tectonic regime of the broader Southern Aegean Sea area as well as with the volcanic processes. The main cluster of the epicenters is located at the Coloumbo Reef, a submarine volcano of the volcanic system of Santorini Islands. A smaller cluster of events is located near the Anydros Islet, aligned in a NE–SW direction, running almost along the main tectonic feature of the area under study, the Santorini–Amorgos Fault Zone. In contrast, the main Santorini Island caldera is characterized by the almost complete absence of seismicity. This contrast is in very good agreement with recent volcanological and marine studies, with the Coloumbo volcanic center showing an intense high-temperature hydrothermal activity, in comparison to the corresponding low-level activity of the Santorini caldera. The high-resolution hypocentral relocations present a clear view of the volcanic submarine structure at the Coloumbo Reef, showing that the main seismic activity is located within a very narrow vertical column, mainly at depths between 6 and 9 km. The focal mechanisms of the best-located events show that the cluster at the Coloumbo Reef is associated with the “Kameni–Coloumbo Fracture Zone”, which corresponds to the western termination of the major ENE–WSW Santorini–Amorgos Fault Zone. Stress–tensor inversion of the available fault plane solutions from Coloumbo Reef, as well as existing neotectonic fault information from NE Santorini (Coloumbo peninsula), suggests that the NE Santorini–Coloumbo faults belong to a single rupture system, with a ~ 30° rotation of the local stress field with respect to the NNW–SSE regional extension field of the southern Aegean Sea. The observed change of the fault plane solutions shows that local conditions at the Coloumbo submarine volcano area control the observed faulting pattern.

Novel regiochemistry in the aqueous singlet oxygen ene reactions of carboxylic acid salts: a comparison of substrate structure

The singlet oxygen ( 1Δ g) photooxidations of angelic acid salt ( 1 ), tiglic acid salt ( 2 ), 2,3-dimethyl-2-butenoic acid salt ( 3 ), 3-ethoxycarbonyl-5,6-dihydro-2-methyl-4 H-pyrane acid salt ( 4 ), cis-3-hexenoic acid salt ( 5 ), and trans-3-hexenoic acid salt ( 6 ) were conducted in deuterated water. The major and minor ene allylic hydroperoxide products were quantified and indicate that the allylic hydrogen geminal to the carboxylate group is preferentially abstracted in 1– 4 , whereas the allylic hydrogen α to the carboxylate is slightly favored for 5 and 6 . We have attributed the observed regiochemistry in 1– 4 to stabilizing hydrogen bonding interactions between the solvent and the perepoxide, which leads to the major ene product.

Intrazeolite Photo‐oxygenation of (R)‐(‐)‐α‐Phellandrene.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Intrazeolite photo-oxygenation of (R)-(-)-α-phellandrene

Thionin-sensitised intrazeolite photo-oxygenation of ( R)-(-)-α-phellandrene affords (1 S,5 R)-5-(1-methylethyl)-2-methylidene-3-cyclohexen-1-yl hydroperoxide as the major ene product. This can be easily reduced with triphenylphosphine to the natural product trans-yabunikkeol.

Late Mesozoic reactivation of Variscan faults in the North Celtic Sea Basin, Ireland

Three major ENE trending reactivated fault systems downthrow to the north-west in the north-western part of the North Celtic Sea Basin. They control the location of three Mesozoic half-grabens. The location of the faults is determined by the underlying basement structures. These are Variscan in age although they exploit older Caledonide trends. Comparison of the Variscan structures identified in the area with regional structures suggests a series of imbricate thrust features. These structures, reactivated during the Mesozoic, controlled both the location and depositional histories of the half-graben basins in the region.

Sedimentological evidence for a major subsurface fracture system linking the eastern Campsie and the eastern Ochil faults

Synopsis Evidence for intra-Carboniferous and end-Carboniferous right-lateral strike slip within the Midland Valley is concentrated along lineaments which reflect major subsurface fracture systems. One such lineament runs ENE below the Kincardine Basin and joins the eastern Campsie Fault to the eastern Ochil Fault. This moved right-laterally during the deposition of the Passage Group, as proved by contemporaneous movements of its associated oblique folds. The hinge line between the Tulliallan Trough ‘low’ and the Bogside Saddle ‘high’ follows this lineament. The ‘low’ controlled the locus of the major Saline Channel Belt throughout most of the Namurian, whereas unusually thick peats commonly accumulated over the ‘high’. Reversals of apparent downthrow along this hinge reflected movements, probably right-lateral strike slip, along the underlying lineament. Low-angle detachments may explain the absence of any major ENE–WSW trending surface fracture above the lineament in the Kincardine Basin. The lineament, which probably extends WSW below the eastern part of the Milngavie–Kilsyth Fault to underlie the Paisley Ruck, may have been initiated as a Riedel Shear by right-lateral strike-slip along the Highland Boundary Fault, or it may reflect a reactivated Late–Caledonian left-lateral strike-slip fault system.

Stratigraphy in an accretionary prism: the Ordovician rocks in North Down, Ireland

ABSTRACTSediments, mainly sandstones, conglomerates and shales, accumulated in small turbidite fans along the northern arc–trench margin of the Iapetus Ocean from middle Ordovician to Silurian time. These fans, together with the underlying pelagic facies and part of the oceanic crust, were sliced and accreted northward resulting in the Lower Palaeozoic accretionary prism which forms the Scottish Southern Uplands and the Longford-Down inlier in Ireland. North Down is the continuation of the Northern belt of the Southern Uplands of Scotland into Ireland, bounded to the S by the Orlock Bridge fault. Lithological and petrographical comparison with the rest of the Northern belt indicates closer affinities with the Southern Uplands of Scotland than with the western end of the Longford-Down inlier. Major ENE—WSW-trending Caledonian strike faults define five blocks, in which new formations of Caradoc and ? Ashgill age are defined. Pillowed spilitic rock, interpreted as a fragment of the ocean-floor, is only recognised in the Ballygrot block. Pelagic and hemipelagic black shales and cherts are overlain by arenaceous sediments in all blocks.