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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2005.03.014 Byline: Hideaki Miyamoto (a)(b), Giuseppe Mitri (a)(c), Adam P. Showman (a), James M. Dohm (d) Keywords: Europa; Satellites of Jupiter; Surfaces; Ices; Volcanism Abstract: Europa's surface exhibits numerous small dome-like and lobate features, some of which have been attributed to fluid emplacement of ice or slush on the surface. We perform numerical simulations of non-Newtonian flows to assess the physical conditions required for these features to result from viscous flows. Our simulations indicate that the morphology of an ice flow on Europa will be, at least partially, influenced by pre-existing topography unless the thickness of the flow exceeds that of the underlying topography by at least an order of magnitude. Three classes of features can be identified on Europa. First, some (possibly most) putative flow-like features exhibit no influence from the pre-existing topography such as ridges, although their thicknesses are generally on the same order as those of ridges. Therefore, flow processes probably cannot explain the formation of these features. Second, some observed features show modest influence from the underlying topography. These might be explained by ice flows with wide ranges of parameters (ice temperatures >230 K, effusion rates >10.sup.7 m.sup.3ayear.sup.-1, and a wide range of grain sizes), although surface uplift (e.g., by diapirism) and in situ disaggregation provide an equally compelling explanation. Third, several observed features are completely confined by pre-existing topographic structures on at least one side; these are the best known candidates for flow features on Europa. If these features resulted from solid-ice flows, then temperatures >260 K and grain sizes Author Affiliation: (a) Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA (b) Department of Geosystem Engineering, University of Tokyo, Tokyo 113-8656, Japan (c) International Research School of Planetary Sciences, University G. d'Annunzio, Pescara, Italy (d) Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ, USA Article History: Received 11 July 2004; Revised 9 March 2005

The undulating, warped, and densely fractured surfaces of highland regions east of Valles Marineris (located north of the eastern Aureum Chaos, east of the Hydraotes Chaos, and south of the Hydaspis Chaos) resulted from extensional surface warping related to ground subsidence, caused when pressurized water confined in subterranean caverns was released to the surface. Water emanations formed crater lakes and resulted in channeling episodes involved in the excavation of Ares, Tiu, and Simud Valles of the eastern part of the circum-Chryse outflow channel system. Progressive surface subsidence and associated reduction of the subsurface cavernous volume, and/or episodes of magmatic-driven activity, led to increases of the hydrostatic pressure, resulting in reactivation of both catastrophic and non-catastrophic outflow activity. Ancient cratered highland and basin materials that underwent large-scale subsidence grade into densely fractured terrains. Collapse of rock materials in these regions resulted in the formation of chaotic terrains, which occur in and near the headwaters of the eastern circum-Chryse outflow channels. The deepest chaotic terrain in the Hydaspis Chaos region resulted from the collapse of pre-existing outflow channel floors. The release of volatiles and related collapse may have included water emanations not necessarily linked to catastrophic outflow. Basal warming related to dike intrusions, thermokarst activity involving wet sediments and/or dissected ice-enriched country rock, permafrost exposed to the atmosphere by extensional tectonism and channel incision, and/or the injection of water into porous floor material, may have enhanced outflow channel floor instability and subsequent collapse. In addition to the possible genetic linkage to outflow channel development dating back to at least the Late Noachian, clear disruption of impact craters with pristine ejecta blankets and rims, as well as preservation of fine tectonic fabrics, suggest that plateau subsidence and chaos formation may have continued well into the Amazonian Period. The geologic and paleohydrologic histories presented here have important implications, as new mechanisms for outflow channel formation and other fluvial activity are described, and new reactivation mechanisms are proposed for the origin of chaotic terrain as contributors to flooding. Detailed geomorphic analysis indicates that subterranean caverns may have been exposed during chaos formation, and thus chaotic terrains mark prime locations for future geologic, hydrologic, and possible astrobiologic exploration. Keywords: Mars; Surface; Geological processes

Ancient wet aeolian (wet-sabkha) environments on Earth, represented in the Entrada and Navajo sandstones of Utah, contain pipe structures considered to be the product of gas/water release under pressure. The sediments originally had considerable porosity allowing the ingress of living plant structures, microorganisms, clay minerals, and fine-grained primary minerals of silt and sand size from the surface downward in the sedimentary column. Host rock material is of a similar size and porosity and presumably the downward migration of fine-grained material would have been possible prior to lithogenesis and final cementation. Recent field emission scanning electron microscopy (FESEM) and EDS (energy-dispersive spectrometry) examination of sands from fluidized pipes in the Early Jurassic Navajo Sandstone reveal the presence of fossil forms resembling fungal filaments, some bearing hyphopodium-like structures similar to those produced by modern tropical leaf parasites. The tropical origin of the fungi is consistent with the paleogeography of the sandstone, which was deposited in a tropical arid environment. These fossil fungi are silicized, with minor amounts of Ca[CO.sub.3] and Fe, and in some cases a Si/Al ratio similar to smectite. They exist as pseudomorphs, totally depleted in nitrogen, adhering to the surfaces of fine-grained sands, principally quartz and orthoclase. Similar wet aeolian paleoenvironments are suspected for Mars, especially following catastrophic sediment-charged floods of enormous magnitudes that are believed to have contributed to rapid formation of large water bodies in the northern plains, ranging from lakes to oceans. These events are suspected to have contributed to a high frequency of constructional landforms (also known as pseudocraters) related to trapped volatiles and water-enriched sediment underneath a thick blanket of materials that were subsequently released to the martian surface, forming piping structures at the near surface and constructional landforms at the surface. This constructional process on Mars may help unravel the complex history of some of the piping structures observed on Earth; on Earth, evidence for the constructional landforms has been all but erased and the near-surface piping structures exposed through millions of years of differential erosion and topographic inversion now occur as high-standing promontories. If the features on both Earth and Mars formed by similar processes, especially involving water and other volatiles, and since the piping structures of Earth provided suitable environments for life to thrive in, the martian features in the northern plains should be considered as prime targets for physico/mineral/chemical/microbiological analyses once the astrobiological exploration of the red planet begins in earnest. Keywords: Extraterrestrial life; Entombed microorganisms on sand clasts; Pipe-like structures on Mars and Earth

Abstract: Numerous boulders have been identified on the 320m-sized asteroid, Itokawa, which is puzzling especially due to its extremely low gravity environment (the escape-velocity is only ∼20cm/s). Through image analysis, we propose that gravels on the surface of this asteroid are likely unconsolidated and have been rearranged after their accumulation. The rearrangements of gravels may occur even now because the asteroid might be hit by meteoroids continuously. Although the possibility of rearrangement during the observational period of Hayabusa spacecraft is small, we scrutinize 19 pairs of high resolution images taken at different times to find if any surface modification occurs. As a result, no convincing evidence of surface modification is found. Thrusters of the Hayabusa spacecraft were activated at close range from the asteroid during its landing phases, which do not cause any identifiable changes. Nevertheless, this does not necessarily indicate that the gravels are consolidated because the observational period is too short to expect vibrations large enough to activate gravels into motion. A longer observational period, or an experiment of a carefully-arranged artificial impact, would be required to properly address why unconsolidated gravels exist on such a low gravity environment and whether this is a typical situation for a small asteroid. [Copyright &y& Elsevier]

Purpose: Neurovascular injury is a serious complication after surgery for Dupuytren disease. The purpose of this study was to evaluate the relationship between the cord and the neurovascular bundle ultrasonographically. Methods: We included 22 healthy volunteers and 14 Dupuytren disease patients (25 fingers) in this study. We evaluated the cord and the digital artery with high-resolution ultrasound. We first investigated the effect of the angle of metacarpophalangeal joint on the position of the radial and ulnar digital arteries in volunteers without evidence of Dupuytren disease. We compared 3 parameters of the radial and ulnar digital arteries, including differences in depth, differences in lateral shift, and the shape of the cross-section of the artery, between volunteers and patients with Dupuytren disease. Results: None of these parameters changed with flexion of the metacarpophalangeal joint of 0°, 30°, and 60°. Digital arteries and cords could be identified ultrasonographically in all patients, and we confirmed ultrasonographic findings by operative findings in 13 fingers. We classified the fingers into 3 subgroups based on the ultrasonographic findings: type A (n = 13), in which the cord was above the artery; type B (n = 5), in which the cord was below the artery; and type C (n = 7), in which the cord was located between the radial and ulnar digital arteries. Types A, B, and C corresponded to natatory cord/abductor digiti minimi cord, spiral cord, and central cord, respectively. Comparisons among volunteers and patient subgroups showed that the difference in depth in type B patients was significantly larger than that of the other groups. When we set the cutoff point of the difference in depth to 3 mm, sensitivity and specificity to detect the spiral cord were 80% and 76%, respectively. Conclusions: The relationship between the neurovascular bundle and the type of Dupuytren disease cord can be evaluated by high-resolution ultrasound. Type of study/level of evidence: Diagnostic III. [Copyright &y& Elsevier]

Purpose: The cause of snapping in trigger finger is not clearly understood. The purpose of this study was to investigate the influence of stiffness of the first annular pulley on snapping in trigger finger patients with sonoelastography, a new technique for quantitative assessment of the stiffness of soft tissues. Methods: We first studied 20 healthy volunteers (all women, aged 24–78 y) to define the change of stiffness with aging and with specific fingers. We then studied 10 digits of 9 patients (all women, aged 60–78 y) with trigger finger that involved middle or ring fingers. Thickness and stiffness were evaluated by sonoelastography. Stiffness was estimated by strain ratio of subcutaneous fat to the pulley (F/P strain ratio). The patients were treated with corticosteroid injection, and the measurement was repeated 3 weeks later. Results: In the healthy volunteers, both thickness and F/P strain ratio showed a positive correlation with age. There was no difference between the middle and ring fingers. In trigger finger patients, the pulley thicknesses of the affected finger and the adjacent normal finger before corticosteroid injection were 0.99 ± 0.19 mm and 0.60 ± 0.14 mm (mean ± SD), respectively. The F/P strain ratios of the affected finger and the adjacent normal finger before the injection were 4.2 ± 1.3 and 2.4 ± 0.63, respectively. Three weeks after the injection, snapping disappeared in all patients, the pulley thickness decreased to 0.61 ± 0.15 mm, and the F/P strain ratio decreased to 2.5 ± 0.68. The cross-sectional area for flexor tendons within the pulley did not change after the injection. Conclusions: Increased stiffness and thickening of the A1 pulley are considered to be causes for snapping in trigger finger, and corticosteroid injection can alleviate snapping by changing these 2 features. Type of study/level of evidence: Diagnostic III. [ABSTRACT FROM AUTHOR]

Abstract: Study Objective: To assess the pathogenesis of catamenial pneumothorax associated with endometriosis from a gynecologic perspective. Design: Retrospective study (Canadian Task Force classification II–2). Setting: University hospital. Patients: Eleven patients with clinically suspected catamenial pneumothorax due to frequently recurrent pneumothorax who underwent thoracoscopy between September 2003 and February 2007 at our hospital. Intervention: Video-assisted thoracoscopy. Measurements and Main Results: Episodes of pneumothorax, coexistence of intrapelvic endometriosis, classification of intrathoracic lesions according to the appearance of pelvic endometriosis using the revised American Society of Reproductive Medicine (re-ASRM) classification, and histopathologic findings in intrathoracic specimens were assessed. A total of 38 episodes of pneumothorax, all on the right side, were documented in 11 patients with catamenial pneumothorax. Median (range) patient age at the initial pneumothorax was 42 (29–47) years. The re-ASRM score in 6 patients in whom pelvic endometriosis was directly observed at laparoscopy and laparotomy was 56 (18–96). We postoperatively reviewed videotape recordings of video-assisted thoracoscopy, and observed superficial thoracic diaphragmatic lesions classified as red (n = 5), black (n = 8), and white (n = 9) with fenestration according to the re-ASRM classifications for pelvic endometriosis. Tissue associated with endometriosis was detected at histopathologic analysis of resected diaphragmatic lesions in 9 patients. No endometriosis was identified at histopathologic analysis of visceral pleural lesions in 7 patients who underwent lung resection. Conclusions: Gynecologic evaluation of catamenial pneumothorax associated with endometriosis is crucial to clarify the unelucidated pathogenesis of the disease. [ABSTRACT FROM AUTHOR]

Surface topographic deformations produced by mantle movements are typically estimated using a numerical mantle convection model with the thin-sheet approximation, where the topographic load is assumed to be always balanced with the calculated normal stress at the top of the fixed boundary of the convecting cell. Although this approximation is commonly used due to its relative simplicity, it implicitly neglects the effect of gravitational relaxation over the dynamically uplifted topography. In order to estimate the potential errors of this approximation, we have developed a new Boundary Element model that permits precise calculations of viscous flow movements with flexible boundaries in the gravity field. Our applications of this model to the estimations of topographic uplifts over mantle upwelling zones show that the thin-sheet approximation results in exaggerated topographic values. Thus, we conclude that, by considering the effect of gravitational relaxation, it is possible to significantly increase the accuracy in estimating the effect that mantle convection has on the surface topography. [Copyright &y& Elsevier]

This work presents numerical assessments of possible routing paths for the reported late Pleistocene Missoula floods, which involved Earth''s largest known peak discharges of freshwater. For our numerical model, we adopt the diffusion wave approximation of the shallow-water equation with the empirical Manning coefficient. This simplification is required because (1) most previous studies are one-dimensional or analytical studies based on simple equations, so that our two-dimensional expansion is a natural step towards more sophisticated models; (2) a simple model can easily incorporate the effect of complicated topography; and (3) lower computational costs permit a broader exploration of parameters. Important and new insights obtained from this work include: (1) numerically, we confirm the presence of the Cordilleran Ice Sheet at the time of the Missoula floods; (2) floods with relatively small peak discharges cannot inundate some major reaches, including the Cheney Palouse Scabland Tract; (3) deposits indicative of multiple floods are mostly confined in the locations that can be inundated by relatively lower peak flood discharges; and (4) although Lake Missoula glacial lake failure scenario can reasonably reproduce extensive water coverage, the best fit result to the geological evidence of flooding is obtained when the total water volume is three times larger than that estimated for Glacial Lake Missoula. The above results do not negate previous works, but indicate the need for further detailed field investigation and more sophisticated modeling in order to pursue further understanding of the complex behavior of megaflooding in the Channeled Scabland. [Copyright &y& Elsevier]

Abstract: The Mars Orbital Camera onboard the Mars Global Surveyor spacecraft, which is currently orbiting about Mars, has revealed hundreds of pristine lobate and tongue-shaped flows that closely display the morphological characteristics of terrestrial rock glaciers, both tongue- and lobe-shaped forms. Generally located between 30°S and 47°S latitude on Mars, these terrestrial-like flows have important paleoenvironmental implications, including marking environmental change from current, present cold and dry desert martian conditions to cold wetter climates in the past. Paleoenvironmental conditions, hypothesized to have significantly influenced the dimensions of the terrestrial-like flows, is supported through a simple dynamic model with the power-law rheology. The presence of periglacial landforms on Mars indicates the possible presence of permafrost and potential caches of water for future exobiological exploration. [Copyright &y& Elsevier]

Background: We tried to clarify whether the histologic subtypes and the size of the solid component of an adenocarcinoma are more important predictive factors for invasiveness or prognosis than is total tumor size, even in lung adenocarcinomas that were 2 cm or smaller. Methods: Between 1996 and December 2005, after standard surgical treatment, 82 patients were diagnosed as having adenocarcinoma with a maximum diameter of 2 cm or less. The group comprised 37 females and 45 males, with ages ranging from 41 to 80 years (median, 64). The clinicopathologic records of the patients were examined with regard to age, sex, nodal status, tumor size (largest diameter of the total tumor as well as the largest diameter without the bronchioloalveolar carcinoma [BAC] component [solid component]), serum carcinoembryonic antigen level, and histologic type. These variables were analyzed as risk factors for vascular or lymphatic invasion, lymph node metastasis, and prognosis. Histologic subtype was classified into two groups: mixed BAC (mixed adenocarcinoma with BAC) and minimal or non-BAC (tumors with little or no BAC component). Results: Histologic subtype was a significant predictive factor both for invasiveness (vascular or lymph vessels) and lymph node metastasis, in both univariate and multivariate analysis. Tumor diameter was not a significant factor in either univariate or multivariate analysis (p = 0.28, 0.15, respectively). However, diameter excluding the BAC component was a significant factor for invasiveness in mixed BAC type (p = 0.035), whereas total diameter was not significant (p = 0.28). Finally, histologic subtype and lymph node metastasis were significant prognostic factors for survival in both univariate (p = 0.03, 0.05, respectively) and multivariate (p = 0.04, 0.05, respectively) analyses. The 5-year survival rate was 94.4% (94.1% for pN0) for the mixed BAC type and 71.4% (78.7% for pN0) for the minimal or non-BAC type (p = 0.009; p = 0.04 for pN0 nodes). Conclusions: Small adenocarcinomas can be classified into two categories. The first category is a minimal or non-BAC adenocarcinoma that shows aggressive biological behavior. The second category is a mixed BAC, which demonstrates less invasive or aggressive biological behavior than the minimal or non-BAC type, with the degree of invasiveness being associated with the size of the non-BAC component. [Copyright &y& Elsevier]

Abstract: Unconfined pahoehoe lobes, composed of networks of numerous pahoehoe toes, often show a transverse profile with central thickening and crude bilateral symmetry. The overall widths of individual lobes are often relatively constant compared to the large diversity in widths of individual toes. These observations collectively suggest that there is a lateral self-confinement mechanism at the scale of a lobe. Although previous correlated random walk models successfully address the nature of this mechanism, the underlying physical processes are still not clearly understood. Here, we propose a simplified two-component model for the lateral self-confinement mechanism. The model assumes that the surface crust retains an inner hot core until its overpressure surpasses the strength of the crust. It also assumes that fracturing of the crust occurs at the top of the flow where the crust has the weakest strength, and then a breakout of the hot core spills out to form a new flow unit. Episodic fracturing and subsequent coalescence of multiple toes form a broad lobe, which is then considered theoretically to behave as a single large flow unit. Although simplified, the model can determine the inflated thickness necessary to fracture the crust and the width scale of the lateral spreading with a self-confinement effect. The model also provides theoretical support for the correlated random walk model for pahoehoe emplacement. [Copyright &y& Elsevier]

Background: We have tried to clarify the prognostic significance of metastasis to the highest mediastinal (HM) lymph node in patients with N2 lung cancer who underwent complete dissection of superior mediastinal (including HM) lymph nodes. Methods: This study analyzed 53 patients with N2 nonsmall cell lung cancer who underwent surgical procedures such as lobectomy plus hilar and mediastinal node dissection (T4, neoadjuvant therapy cases were excluded). For patients whose cancer was in the left lung, we performed surgery through the median sternotomy in order to dissect superior mediastinal nodes. The clinicopathologic records of the patients were examined for prognostic factors such as age, sex, side, histology, tumor location, tumor size, clinical node (cN) number, preoperative serum carcinoembryonic antigen level, number of metastatic stations, and HM lymph node involvement. Results: A univariate analysis showed that tumor size (T1/T2-3), cN factor (cN1-2/cN0), N2 level (multiple/single), and metastasis to the HM node were significant prognostic factors. In the multivariate analysis, metastasis to the HM lymph node remained a significant prognostic factor (p = 0.026). The 3-year survival rates were 52% in patients without metastasis to the HM lymph node and 21% in patients with metastasis to the HM lymph node (p < 0.001). Furthermore, when HM nodal involvement was absent, the 5-year survival rate was 33% even in patients with multilevel N2 status, 45% in patients with cN1-2 status, and 47% in patients with pT2-3 tumor status. Conclusions: Highest mediastinal lymph node involvement is prognostic of highly advanced N2 disease resulting in poor outcome. The results also suggest that patients with no involvement of the HM lymph node can experience acceptable postoperative outcomes even if they have multilevel N2 status, positive cN status, or T2-3 tumor status. [Copyright &y& Elsevier]

Summary: We report here 4 cases of multilocular thymic cysts (MTCs) with reactive lymphoid follicular hyperplasia. They were admitted to our hospital to examine anterior mediastinal masses demonstrated on chest computed tomographic scans. Three patients presented high-grade intermittent fever, and 2 patients were associated with Sjogren syndrome with elevated serum antinuclear antibody levels. All patients were subjected to extended thymectomy. Interestingly, their fever disappeared immediately after surgery. Histologically, the lesions were characterized by several cystic spaces separated by various thick walls with dense lymphoid tissue containing large reactive germinal centers. The inner cyst walls were lined by flattened cuboidal epithelia in some portions. Columnar epithelia with focal cilia were partially observed in 2 cases. These pathological findings led to a diagnosis of MTCs that were thought to result from cystic transformation of medullary duct derivatives by acquired inflammatory processes. The pathological findings, together with clinical courses of our cases, suggest that inflammation accompanied by autoimmune diseases may play, in part, an important role in the development of MTCs. [Copyright &y& Elsevier]

Presents a study that estimated the magnitude of the resurge in the case of the marine-target Lockne impact crater in Sweden using numerical modeling. Behavior of the collapsing water cavity and the shape of the flow front when it approaches and fills the inner crater; Topography of the crater; Discussion on the time it takes to fill a crater of the size of Lockne and how this time varies with different target water depths.

Flapping-wing micro air vehicle (FWMAV) is an attractive idea for Mars exploration because of its high capability in a thin atmosphere. The biggest challenge for its development is an appropriate understanding of a flapping flight with flexible wings, which is significantly complicated because flexible flapping wings can undergo large-scale deformations due to the effects of wing inertia and the aerodynamic forces exerted by the surrounding atmosphere. Fluid–structure interaction (FSI) analysis is a powerful tool for accurate investigations, but it usually has a very high computational cost, making it challenging to perform necessary parametric studies for practical designing. An efficient FSI analysis method is required. On Mars, whose atmospheric density is around 1% that of Earth, aerodynamic forces have a relatively small influence on wing deformation and may even be negligible in some cases. We thus investigate the relative contributions of the inertial force of a flapping wing and the aerodynamic forces exerted by the surrounding Martian atmosphere using a two-way coupled FSI simulation, and identify the conditions under which the aerodynamic forces are negligible. Then, we develop a computationally efficient one-way coupled FSI analysis system based on the interface-capturing method to design a flexible flapping wing for Mars exploration. Under the obtained conditions, we perform parametric studies on hovering flight with flexible flapping wings in the Martian environment with multiple aerodynamic parameters, various kinematic parameters, and material properties of the wing. We conclude that an FWMAV with a payload of around 5 g can fly for more than 1 min for the maximum density of the Martian atmosphere. • Inertial and aerodynamic force was analyzed using a two-way coupled FSI analysis. • A one-way coupled FSI analysis system was developed for efficient parametric study. • We found a design solution that can fly for more than 1 min with about 5 g payloads. [ABSTRACT FROM AUTHOR]

Catastrophic floods of enormous proportions played a major role in the excavation of some of the Solar System׳s largest channels, the circum-Chryse outflow channels. The generation of the floods has been attributed to both the evacuation of regional highland aquifers and ancient paleo-lakes. Numerous investigators indicate that these source regions were likely recharged and pressurized by eastward groundwater flow via conduits extending thousands of kilometers from an elevated groundwater table in the Tharsis volcanic rise. This hypothesis remains controversial, largely because subsequent stages of Valles Marineris development and enlargement would have resulted in the widespread destruction of the proposed groundwater pathways. Here, we show that Noctis Labyrinthus, a unique system of troughs connecting the Tharsis volcanic rise and western Valles Marineris, retains geologic evidence of conduit development associated with structurally-controlled groundwater flow through salt-rich upper crustal deposits. The inferred groundwater flow spatial pattern is in agreement with aquifer drainage from the Tharsis volcanic rise region. Our investigation indicates that subsequent surface collapse over these conduits during the Hesperian Period resulted in the generation of large basins in the central and eastern regions of Noctis Labyrinthus, and contributed to chasmata formation in the western portion of Valles Marineris. The lava-covered floors of these basins, dated by previous workers as Late Amazonian, contain hydrated mineral deposits coexisting spatially with decameter-scale features that we interpret to be lacustrine and periglacial in origin. The proposed paleo-lake sites also include chaotic terrains, which could comprise groundwater discharge zones, pointing to regional hydrologic processes that likely operated from the Early Hesperian until a few tens of millions of years ago. Episodic fluidized discharges from eastern Noctis Labyrinthus troughs delivered vast volumes of sediments and volatiles into western Valles Marineris, contributing to the construction of a regional volatile-rich stratigraphy. Intermittent formation of lakes within regional tectono-volcanic basins could have lasted hundreds of millions of years, thus, we highlight the potential of Noctis Labyrinthus as a region of prime interest for astrobiological exploration. [ABSTRACT FROM AUTHOR]

The details of the structure of the core are important to understanding the evolution and thermal history of the Moon. Even with existing information, including seismic measurements from the Apollo mission, as well as geodetic measurements from Lunar Laser Ranging (LLR) data and gravity, it is still difficult to constrain the size of the lunar core and its density with certainty. Here, we investigate the radius and density of the lunar core using simple constraints of the estimated mean density and mean moment of inertia of the Moon with the help of a Monte Carlo simulation algorithm. This includes a comparison between the results based from the more recent GRAIL gravity field model GRGM660PRIM with those of the gravity field model SGM100h. Analysis through an improved gravity field model indicates that the lunar core is smaller and denser than previously estimated, and the result (a core radius with 370 km) is consistent with more recent result. [ABSTRACT FROM AUTHOR]

Fossil mesofauna and bacteria recovered from a paleosol in a moraine situated adjacent to the inland ice, Antarctica, and dating to the earliest glacial event in the Antarctic Dry Valleys opens several questions. The most important relates to understanding of the mineralogy and chemistry of the weathered substrate habitat in which Coleoptera apparently thrived at some point in the Early/Middle Miocene and perhaps earlier. Here, Coleoptera remains are only located in one of six horizons in a paleosol formed in moraine deposited during the alpine glacial event (>15 Ma). A tendency for quartz to decrease upward in the section may be a detrital effect or a product of dissolution in the early stage of profile morphogenesis when climate was presumably milder and the depositing glacier of temperate type. Discontinuous distributions of smectite, laumontite, and hexahydrite may have provided nutrients and water to mesofauna and bacteria during the early stage of biotic colonization of the profile. Because the mesofauna were members of burrowing Coleoptera species, future work should assess the degree to which the organisms occupied other sites in the Dry Valleys in the past. Whereas there is no reasonable expectations of finding Coleoptera/insect remains on Mars, the chemistry and mineralogy of the paleosol is within a life expectancy window for the presence of microorganisms, principally bacteria and fungi. Thus, parameters discussed here within this Antarctic paleosol could provide an analogue to identifying similar fossil or life-bearing weathered regolith on Mars. [ABSTRACT FROM AUTHOR]

Objective: To explore diaphragmatic lesions that are potentially associated with catamenial pneumothorax by using an advanced flexible laparoscope with wide optic angle. Design: Case report. Setting: University hospital. Patient(s): A 30-year-old woman who was scheduled for thoracoscopic surgery because of recurrent right-sided catamenial pneumothorax. Intervention(s): The peritoneal surface of the diaphragm was explored with an advanced flexible laparoscope that was equipped with a charge-coupled device on the tip, concurrently with thoracoscopic surgery. Main Outcome Measure(s): Lesions associated with endometriosis on the peritoneal surface of the posterior diaphragm abutting the posterior abdominal wall and liver. Result(s): When the flexible laparoscope was inserted via an umbilical trocar and the peritoneal surface of the right-sided diaphragm was explored, guided by illumination from the thoracoscope, scattered specific lattice lesions and fenestrations were identified in the central tendon of the posterior diaphragm, a region that cannot be visualized with the conventional rigid laparoscope. Conclusion(s): By using the flexible laparoscope, endometriotic lesions potentially related to catamenial pneumothorax were identified on the posterior diaphragm. [Copyright &y& Elsevier]

SCIDDICA S4c is the latest hexagonal release of a family of Cellular Automata models for the simulation of flow-type landslides. It is able to simulate the erosion of the regolith along the flow path, besides branching and re-joining events of the flow masses. Dissipative effects are modelled in terms of not-exclusive velocity-dependent mechanisms, which allow to simulate even complex rheological behaviours. Moreover, it is able to manage the peculiar characteristics of rapid flows, and the effects of mass collisions, by guaranteeing mass conservation. In case of no dissipation, conservation of energy and momentum are also assured. Model calibration has been carried out through parallel Genetic Algorithms, by considering the May 1998 Curti-Sarno (Campania, Southern Italy) debris flow. A preliminary analysis has also been performed, aiming at evaluating the sensitivity of the model with respect to a sub-set of model parameters, the size of the cell, the orientation of the cellular space, and noise in input data. Calibration confirmed the reliability of the model in reproducing the considered case of study. Moreover, sensitivity analyses pointed out its robustness with respect to the considered factors, by highlighting their different weight in affecting the behaviour of the simulations. [Copyright &y& Elsevier]

Summary: Carbonic anhydrase (CA) IX catalyzes the hydration of carbon dioxide into carbonic acid and participates in a variety of physiological and biological processes. The aim of this study was to evaluate the prognostic significance of CA IX expression in patients with lung adenocarcinoma. Standard immunohistochemical techniques were used to study CA IX expression in 134 patients who underwent curative resection for adenocarcinoma of the lung at our hospital between January 1995 and December 1996. We evaluated the correlations between CA IX expression levels on cancer cells and clinicopathological factors. CA IX expression was not observed in normal lung tissue or specimens from non-invasive adenocarcinomas. CA IX immunostaining was detected in 33 (24.6%) invasive adenocarcinoma cases. Poor differentiated histological phenotype (p =0.0015), pathological stage (p =0.0400), vascular invasion (p =0.0009) and lymphatic permeation (p =0.0050) were significantly related to CA IX expression. On univariate analysis, CA IX positive cases showed significantly shorter overall survival (p =0.0083) and disease-free survival (p =0.0122). In particular, the overall and disease-free survivals in stages I+II were significantly shorter in the CA IX positive than in the CA IX negative cases (p =0.0269 and 0.0011, respectively). Our results suggest that CA IX expression is strongly associated with tumor progression and indicates a poor prognosis for patients with stages I+II lung adenocarcinoma. [Copyright &y& Elsevier]

Recent asteroid missions have revealed that many sub-kilometer asteroids are rubble piles. Large parts of their surfaces are covered with boulders larger than tens of centimeters. An evaluation of the abundance and size distribution of boulders provides clues to understand surface processes on boulder-covered asteroids. Here we report a new method that automatically measures the abundance of small boulders (sub-pixel to a few pixels), whose boundaries cannot be recognized with visual inspection, by quantifying the surface radiance variation that occurs during the spinning of the asteroid. After validating our approach with previous boulder counting data, we apply this method to images of the asteroids Ryugu and Itokawa, which were visited by JAXA's Hayabusa and Hayabusa2, and obtain a global distribution of the boulders larger than 0.75–3 ​m, which corresponds to 1.5–6 pixels. We find that the boulder number density of this size range is smaller (1) on the western bulge than on the eastern hemisphere and (2) on the equatorial ridge than on the higher latitudes, both of which exceed the number density of boulders ​> ​5 ​m by an order of magnitude. The boulder size distribution at 1.25–20 ​m shows that the boulders smaller than 1 ​m are more abundant at the equator than at mid-latitudes, while those larger than 1 ​m in diameter are more abundant at mid-latitudes than at the equator. This contrast suggests size-dependent migration of boulders in the latitudinal direction. We also find that the typical boulder size (the size reaching the cumulative areal coverage of 50%) is 1.9 ​m at the equatorial region (10°S-10°N) while it is 2.6 ​m at mid-latitudes (40°S-50°S, 40°N-50°N). The typical boulder size is also smaller in the western bulge (2.0–2.2 ​m). We construct global maps of the power-law index of the size frequency distribution of boulders and find minor variations over the entire surface of Ryugu (−2.53 ​± ​0.03) for boulders larger than 1.25 ​m. This small variation suggests homogeneous size sorting processes on Ryugu. Surface roughness does not show a significant correlation with the v-band albedo but shows a high anti-correlation (R ​= ​−0.73) with the current geological slope on the eastern hemisphere. Our method is useful enhancement of smooth area detection and boulder distribution characterization that will be applicable to other planetary explorations in the future, including those of Phobos and other asteroids. • Automatic analysis of pixel-scale boulders based on pixel radiance variation as asteroid spins. • Distribution of sub-meter boulders on Ryugu indistinguishable from visual counting. • Method detects the east-west dichotomy in the distribution of small boulders (several meters in diameter). • Uniform power-law index of boulder size frequency distribution on Ryugu suggests homogeneous size sorting. • Boulder distribution is correlated with current geologic slope. [ABSTRACT FROM AUTHOR]