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Abstract: Analysis of Galileo Near‐Infrared Mapping Spectrometer observations of Marduk Fluctus, a volcano on the Jovian moon Io, reveals a style of volcanic activity not previously seen there—a powerful thermal event lasting only a few minutes in 1996. The thermal emission rapidly fades, suggesting extremely rapid cooling of small clasts. The duration and evolution of the explosive eruption are akin to what might be expected from a strombolian or vulcanian explosion. The presence of such events provides an additional volcanic process that can be imaged by future missions with the intent of determining lava composition from eruption temperature, an important constraint on the internal composition of Io. These data promise to be of particular use in understanding the mechanics of explosive volcanic processes on Io. [ABSTRACT FROM AUTHOR]

Hyperion is Saturn’s largest known irregularly shaped satellite and the only moon observed to undergo chaotic rotation. Previous work has identified Hyperion’s surface as distinct from other small icy objects but left the causes unsettled. Here we report high-resolution images that reveal a unique sponge-like appearance at scales of a few kilometres. Mapping shows a high surface density of relatively well-preserved craters two to ten kilometres across. We have also determined Hyperion’s size and mass, and calculated the mean density as 544 ± 50 kg m-3, which indicates a porosity of >40 per cent. The high porosity may enhance preservation of craters by minimizing the amount of ejecta produced or retained, and accordingly may be the crucial factor in crafting this unusual surface. [ABSTRACT FROM AUTHOR]

The Cassini Imaging Science Subsystem (ISS) began observing Saturnin early February 2004. From analysis of cloud motions through earlyOctober 2004, we report vertical wind shear in Saturn's equatorial jetand a maximum wind speed of ∼375 meters per second, a value thatdiffers from both Hubble Space Telescope and Voyager values. We alsoreport a particularly active narrow southern mid-latitude region inwhich dark ovals are observed both to merge with each other and to arisefrom the eruptions of large, bright storms. Bright storm eruptions arecorrelated with Saturn's electrostatic discharges, which are thought tooriginate from lightning. [ABSTRACT FROM AUTHOR]

The Cassini Imaging Science Subsystem acquired high-resolutionimaging data on the outer Saturnian moon, Phoebe, during Cassini's closeflyby on 11 June 2004 and on lapetus during a flyby on 31 December 2004.Phoebe has a heavily cratered and ancient surface, shows evidence of icenear the surface, has distinct layering of different materials, and hasa mean density that is indicative of an ice-rock mixture, lapetus's darkleading side (Cassini Regio) is ancient, heavily cratered terrainbisected by an equatorial ridge system that reaches 20 kilometersrelief. Local albedo variations within and bordering Cassini Regiosuggest mass wasting of ballistically deposited material, the origin ofwhich remains unknown. [ABSTRACT FROM AUTHOR]

Images acquired of Saturn's rings and small moons by the CassiniImaging Science Subsystem (ISS) during the first 9 months of Cassinioperations at Saturn have produced many new findings. These include newsaturnian moons; refined orbits of new and previously known moons;narrow diffuse rings in the F-ring region and embedded in gaps withinthe main rings; exceptionally fine-scale ring structure in moderate- tohigh-optical depth regions; new estimates for the masses of ringregionmoons, as well as ring particle properties in the Cassini division,derived from the analysis of linear density waves; ring particle albedosin select ring regions; and never-before-seen phenomena within therings. [ABSTRACT FROM AUTHOR]

Provides information on the observations about the high-resolution images of volcanically active Io from the Galileo spacecraft. Characteristics of pele; Eruption near Pillan Patera in June 1997; Description of the zamama; Information on prometheus, a plume visible in every observation sequence by the Voyager and Galileo spacecrafts.

Purpose: Serum C-reactive protein has been shown to have prognostic value in localized and metastatic renal cell carcinoma. However, the prognostic value of intratumor C-reactive protein remains unknown., Materials and Methods: A total of 95 patients with resected, clinically localized (T1-T4N0M0) clear cell renal cell carcinoma were followed postoperatively. Intratumor C-reactive protein expression was assessed in surgical specimens using immunohistochemical analysis. Patients were categorized by staining intensity into low risk (staining 0 to 1), intermediate risk (staining 2) and high risk (staining 3) groups. Kaplan-Meier and multivariate Cox regression analyses were used to examine overall survival across patient and disease characteristics. Variables examined in multivariate Cox regression analysis included T stage, Fuhrman nuclear grade, tumor size, preoperative serum C-reactive protein and intratumor C-reactive protein staining., Results: Followup extended up to 46 months with a mean (SD) of 29.8 (11.0) months. Twelve patients (12.6%) died during followup. Of all tumors 49.5%, 25.3% and 25.3% were graded by intratumor C-reactive protein staining as low risk (0 to 1), intermediate risk (2) and high risk (3), respectively. After controlling for variables significant on univariate analysis, patients in the high risk (3) group experienced a 27-fold increased risk of overall mortality compared to those in the low risk (0-1) group (HR 27.767, 95% CI 1.488-518.182). After adjusting for tumor staining, preoperative serum C-reactive protein was not a significant predictor of overall survival (p = 0.741)., Conclusions: Intratumor C-reactive protein may be a robust biomarker of prognosis in patients with localized renal cell carcinoma., (Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Objectives: Preoperative C-reactive protein (CRP) predicts metastasis and mortality in localized renal cell carcinoma (RCC). However, the predictive potential of after resection of localized RCC remains unclear. Therefore, we assessed the absolute ability of postoperative CRP to predict metastases and mortality as a continuous variable., Methods: Patients with clinically localized (T1-T3N0M0) clear-cell RCC were followed for 1 year postoperatively. Metastases were identified radiologically and mortality by death certificate. Univariate and multivariate binary logistic regression analyses examined 1 year relapse-free survival (RFS) and overall survival (OS) across patient and disease characteristics., Results: Of the 110 patients in this study, 16.4% developed metastases and 6.4% died. Mean (SD) postoperative CRP for patients who did and did not develop metastases were 69.06 (73.55) mg/L and 5.27 (7.80), respectively. Mean (SD) postoperative CRP for patients who did and did not die were 89.31 (69.51) mg/L and 10.88 (30.32), respectively. In multivariate analysis, T-stage (OR: 12.452, 95% CI: 2.889-53.660) and postoperative CRP ((B: .080, SE: .025; P < .001) were significant predictors of RFS. T-Stage (OR: 11.715; 95% CI: 1.102-124.519) and postoperative CRP (B: .017; SE: .007; P < .001) were also significant predictors of OS. After adjusting for postoperative CRP, preoperative CRP was not predictive of these outcomes., Conclusions: Postoperative, not preoperative, CRP is the better predictor of metastasis and mortality following nephrectomy for localized RCC. Clinicians should consider absolute postoperative CRP to identify high-risk patients for closer surveillance or additional therapy. Predictive algorithms should consider incorporating postoperative CRP as a continuous variable to maximize predictive ability., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Purpose: C-reactive protein is an inflammatory biomarker associated with tumor burden and metastasis in renal cell carcinoma. Recent studies suggest that preoperative C-reactive protein predicts metastasis and mortality after nephrectomy for localized renal cell carcinoma. However, these studies dichotomized C-reactive protein (typically 10 mg/l or greater vs less than 10 mg/l). Considering the continuous range of C-reactive protein (less than 1 mg/l to greater than 100 mg/l) we assessed the ability of absolute preoperative C-reactive protein to predict metastases and mortality as a continuous variable., Materials and Methods: Patients with clinically localized (T1-T3N0M0) clear cell renal cell carcinoma were followed for 1 year postoperatively. Metastases were identified radiologically and mortality was determined by death certificate. Univariate and multivariate binary logistic regression analyses examined 1-year relapse-free survival and overall relative survival across patient and disease characteristics., Results: Of the 130 patients in this study metastases developed in 24.6% and 10.8% of the patients died. Mean (SD) preoperative C-reactive protein for patients in whom metastases did and did not develop was 89.17 (74.17) and 9.16 (30.62) mg/l, respectively. Mean preoperative C-reactive protein for patients who did and did not die was 102.61 (77.32) and 19.52 (46.10) mg/l, respectively. On multivariate analysis SSIGN score (p <0.001) and preoperative C-reactive protein (B 0.027, SE 0.003, p <0.001) were significant predictors of relapse-free survival, and preoperative platelets (p = 0.009) and preoperative C-reactive protein (B 0.011, SE 0.008, p <0.001) were significant predictors of overall relative survival., Conclusions: Absolute preoperative C-reactive protein is a robust predictor of metastasis and mortality after nephrectomy for localized renal cell carcinoma. Clinicians should consider absolute preoperative C-reactive protein to identify high risk patients for closer surveillance or additional therapy. In addition, predictive algorithms and models of metastasis should consider incorporating C-reactive protein as a continuous variable to maximize predictive ability., (Copyright 2010 American Urological Association. Published by Elsevier Inc. All rights reserved.)

Stem cell transplantation is currently being explored as a therapy for many neurodegenerative diseases including glaucoma. Cellular therapies have the potential to provide chronic neuroprotection after a single treatment, and early results have been encouraging in models of spinal cord injury and Parkinson's disease. Stem cells may prove ideal for use in such treatments as they can accumulate at sites of injury in the central nervous system (CNS) and may also offer the possibility of targeted treatment delivery. Numerous stem cell sources exist, with embryonic and fetal stem cells liable to be superseded by adult-derived cells as techniques to modify the potency and differentiation of somatic cells improve. Possible neuroprotective mechanisms offered by stem cell transplantation include the supply of neurotrophic factors and the modulation of matrix metalloproteinases and other components of the CNS environment to facilitate endogenous repair. Though formidable challenges remain, stem cell transplantation remains a promising therapeutic approach in glaucoma. In addition, such studies may also provide important insights relevant to other neurodegenerative diseases.

Cassini has identified a geologically active province at the south pole of Saturn's moon Enceladus. In images acquired by the Imaging Science Subsystem (ISS), this region is circumscribed by a chain of folded ridges and troughs at approximately 55 degrees S latitude. The terrain southward of this boundary is distinguished by its albedo and color contrasts, elevated temperatures, extreme geologic youth, and narrow tectonic rifts that exhibit coarse-grained ice and coincide with the hottest temperatures measured in the region. Jets of fine icy particles that supply Saturn's E ring emanate from this province, carried aloft by water vapor probably venting from subsurface reservoirs of liquid water. The shape of Enceladus suggests a possible intense heating epoch in the past by capture into a 1:4 secondary spin/orbit resonance.

The Galileo spacecraft has detected diffuse optical emissions from Io in high-resolution images acquired while the satellite was eclipsed by Jupiter. Three distinct components make up Io's visible emissions. Bright blue glows of more than 300 kilorayleighs emanate from volcanic plumes, probably due to electron impact on molecular sulfur dioxide. Weaker red emissions, possibly due to atomic oxygen, are seen along the limbs, brighter on the pole closest to the plasma torus. A faint green glow appears concentrated on the night side of Io, possibly produced by atomic sodium. Io's disk-averaged emission diminishes with time after entering eclipse, whereas the localized blue glows brighten instead.

Infrared wavelength observations of Io by the Galileo spacecraft show that at least 12 different vents are erupting lavas that are probably hotter than the highest temperature basaltic eruptions on Earth today. In at least one case, the eruption near Pillan Patera, two independent instruments on Galileo show that the lava temperature must have exceeded 1700 kelvin and may have reached 2000 kelvin. The most likely explanation is that these lavas are ultramafic (magnesium-rich) silicates, and this idea is supported by the tentative identification of magnesium-rich orthopyroxene in lava flows associated with these high-temperature hot spots.

Reflectance spectra in the 1- to 2.5-micrometer wavelength region of the surface of Europa obtained by Galileo's Near Infrared Mapping Spectrometer exhibit distorted water absorption bands that indicate the presence of hydrated minerals. The laboratory spectra of hydrated salt minerals such as magnesium sulfates and sodium carbonates and mixtures of these minerals provide a close match to the Europa spectra. The distorted bands are only observed in the optically darker areas of Europa, including the lineaments, and may represent evaporite deposits formed by water, rich in dissolved salts, reaching the surface from a water-rich layer underlying an ice crust.

Ground-based spectroscopy of Jupiter's moon Europa, combined with gravity data, suggests that the satellite has an icy crust roughly 150 km thick and a rocky interior. In addition, images obtained by the Voyager spacecraft revealed that Europa's surface is crossed by numerous intersecting ridges and dark bands (called lineae) and is sparsely cratered, indicating that the terrain is probably significantly younger than that of Ganymede and Callisto. It has been suggested that Europa's thin outer ice shell might be separated from the moon's silicate interior by a liquid water layer, delayed or prevented from freezing by tidal heating; in this model, the lineae could be explained by repetitive tidal deformation of the outer ice shell. However, observational confirmation of a subsurface ocean was largely frustrated by the low resolution (>2 km per pixel) of the Voyager images. Here we present high-resolution (54 m per pixel) Galileo spacecraft images of Europa, in which we find evidence for mobile 'icebergs'. The detailed morphology of the terrain strongly supports the presence of liquid water at shallow depths below the surface, either today or at some time in the past. Moreover, lower-resolution observations of much larger regions suggest that the phenomena reported here are widespread.

Five absorption features are reported at wavelengths of 3.4, 3.88, 4. 05, 4.25, and 4.57 micrometers in the surface materials of the Galilean satellites Callisto and Ganymede from analysis of reflectance spectra returned by the Galileo mission near-infrared mapping spectrometer. Candidate materials include CO2, organic materials (such as tholins containing C(triple bond)N and C-H), SO2, and compounds containing an SH-functional group; CO2, SO2, and perhaps cyanogen [(CN)2] may be present within the surface material itself as collections of a few molecules each. The spectra indicate that the primary surface constituents are water ice and hydrated minerals.

The first images of Jupiter, Io, Europa, and Ganymede from the Galileo spacecraft reveal new information about Jupiter's Great Red Spot (GRS) and the surfaces of the Galilean satellites. Features similar to clusters of thunderstorms were found in the GRS. Nearby wave structures suggest that the GRS may be a shallow atmospheric feature. Changes in surface color and plume distribution indicate differences in resurfacing processes near hot spots on Io. Patchy emissions were seen while Io was in eclipse by Jupiter. The outer margins of prominent linear markings (triple bands) on Europa are diffuse, suggesting that material has been vented from fractures. Numerous small circular craters indicate localized areas of relatively old surface. Pervasive brittle deformation of an ice layer appears to have formed grooves on Ganymede. Dark terrain unexpectedly shows distinctive albedo variations to the limit of resolution.

Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.

Galileo images of Gaspra reveal it to be an irregularly shaped object (19 by 12 by 11 kilometers) that appears to have been created by a catastrophic collisional disruption of a precursor parent body. The cratering age of the surface is about 200 million years. Subtle albedo and color variations appear to correlate with morphological features: Brighter materials are associated with craters especially along the crests of ridges, have a stronger 1-micrometer absorption, and may represent freshly excavated mafic materials; darker materials exhibiting a significantly weaker 1-micrometer absorption appear concentrated in interridge areas. One explanation of these patterns is that Gaspra is covered with a thin regolith and that some of this material has migrated downslope in some areas.

During the 1990 Galileo Venus flyby, the Near Infaied Mapping Spectrometer investigated the night-side atmosphere of Venus in the spectral range 0.7 to 5.2 micrometers. Multispectral images at high spatial resolution indicate substanmial cloud opacity variations in the lower cloud levels, centered at 50 kilometers altitude. Zonal and meridional winds were derived for this level and are consistent with motion of the upper branch of a Hadley cell. Northern and southern hemisphere clouds appear to be markedly different. Spectral profiles were used to derive lower atmosphere abundances of water vapor and other species.

Internal heat flow from radioactive decay in Triton's interior along with absorbed thermal energy from Neptune total 5 to 20 percent of the insolation absorbed by Triton, thus comprising a significant fraction of Triton's surface energy balance. These additional energy inputs can raise Triton's surface temperature between approximately 0.5 and 1.5 K above that possible with absorbed sunlight alone, resulting in an increase of about a factor of approximately 1.5 to 2.5 in Triton's basal atmospheric pressure. If Triton's internal heat flow is concentrated in some areas, as is likely, local effects such as enhanced sublimation with subsequent modification of albedo could be quite large. Furthermore, indications of recent global albedo change on Triton suggest that Triton's surface temperature and pressure may not now be in steady state, further suggesting that atmospheric pressure on Triton was as much as ten times higher in the recent past.

Four geyser-like plumes were discovered near Triton's south pole in areas now in permanent sunlight. Because Triton's southern hemisphere is nearing a maximum summer solstice, insolation as a driver or a trigger for Triton's geyser-like plumes is an attractive hypothesis. Trapping of solar radiation in a translucent, low-conductivity surface layer (in a solid-state greenhouse), which is subsequently released in the form of latent heat of sublimation, could provide the required energy. Both the classical solid-state greenhouse consisting of exponentially absorbed insolation in a gray, translucent layer of solid nitrogen, and the "super" greenhouse consisting of a relatively transparent solid-nitrogen layer over an opaque, absorbing layer are plausible candidates. Geothermal heat may also play a part if assisted by the added energy input of seasonal cycles of insolation.

Hapke's photometric model has been combined with a plane-parallel thin atmospheric haze model to describe Voyager whole-disk observations of Triton, in the violet (0.41 microm), blue (0.48 microm), and green (0.56 microm) wavelength bands, in order to obtain estimates of Triton's geometric albedo, phase integral, and Bond albedo. Phase angle coverage in these filters ranging from approximately 12 degrees to 159 degrees was obtained by combining narrow- and wide-angle camera images. An upturn in the data at the highest phase angles observed can be explained by including scattering in a thin atmospheric haze layer with optical depths systematically decreasing with wavelength from approximately 0.06 in the violet to 0.03 for the green filter data. The geometric albedo, phase integral, and spherical albedo of Triton in each filter corresponding to our best fit Hapke parameters yield an estimated Bond albedo of 0.82 +/- 0.05. If the 14-microbar N(2) atmosphere detected by Voyager is in vapor equilibrium with the surface (therefore implying a surface temperature of 37.5 K), our Bond albedo implies a surface emissivity of 0.59 +/- 0.16.

At least four active geyser-like eruptions were discovered in Voyager 2 images of Triton, Neptune's large satellite. The two best documented eruptions occur as columns of dark material rising to an altitude of about 8 kilometers where dark clouds of material are left suspended to drift downwind over 100 kilometers. The radii of the rising columns appear to be in the range of several tens of meters to a kilometer. One model for the mechanism to drive the plumes involves heating of nitrogen ice in a subsurface greenhouse environment; nitrogen gas pressurized by the solar heating explosively vents to the surface carrying clouds of ice and dark partides into the atmosphere. A temperature increase of less than 4 kelvins above the ambient surface value of 38 +/- 3 kelvins is more than adequate to drive the plumes to an 8-kilometer altitude. The mass flux in the trailing clouds is estimated to consist of up to 10 kilograms of fine dark particles per second or twice as much nitrogen ice and perhaps several hundred or more kilograms of nitrogen gas per second. Each eruption may last a year or more, during which on the order of a tenth of a cubic kilometer of ice is sublimed.

Voyager 2 photography has complemented that of Voyager I in revealing many additional characteristics of Saturn and its satellites and rings. Saturn's atmosphere contains persistent oval cloud features reminiscent of features on Jupiter. Smaller irregular features track out a pattern of zonal winds that is symmetric about Saturn's equator and appears to extend to great depth. Winds are predominantly eastward and reach 500 meters per second at the equator. Titan has several haze layers with significantly varying optical properties and a northern polar "collar" that is dark at short wavelengths. Several satellites have been photographed at substantially improved resolution. Enceladus' surface ranges from old, densely cratered terrain to relatively young, uncratered plains crossed by grooves and faults. Tethys has a crater 400 kilometers in diameter whose floor has domed to match Tethys' surface curvature and a deep trench that extends at least 270 degrees around Tethys' circumference. Hyperion is cratered and irregular in shape. Iapetus' bright, trailing hemisphere includes several dark-floored craters, and Phoebe has a very low albedo and rotates in the direction opposite to that of its orbital revolution with a period of 9 hours. Within Saturn's rings, the "birth" of a spoke has been observed, and surprising azimuthal and time variability is found in the ringlet structure of the outer B ring. These observations lead to speculations about Saturn's internal structure and about the collisional and thermal history of the rings and satellites.

Infrared observations of Io during the 1986 apparition of Jupiter indicate that a large eruptive event occurred on the leading side of Io on 7 August 1986, Universal Time. Measurements made at 4.8, 8.7, and 20 micrometers suggest that the source of the event was about 15 kilometers in radius with a model temperature of approximately 900 Kelvin. Together with previously reported events, these measurements indicate that high-temperature volcanic activity on the leading side of Io may be more frequent than previously thought. The inferred temperature is significantly above the boiling point of sulfur in a vacuum(715 Kelvin) and thus constitutes strong evidence for active silicate volcanism on the surface of Io.

The spectral reflectivity (0.30 to 1.10 microns) of several asteroids has been measured for the first time. The reflection spectrum for Vesta contains a strong absorption band centered near 0.9 micron and a weaker absorption feature between 0.5 and 0.6 micron. The reflectivity decreases strongly in the ultraviolet. The reflection spectrum for the asteroid Pallas and probably for Ceres does not contain the 0.9-micron band. Vesta shows the strongest and best-defined absorption bands yet seen in the reflection spectrum for the solid surface of an object in the solar system. The strong 0.9-micron band arises from electronic absorptions in ferrous iron on the M2 site of a magnesian pyroxene. Comparison with laboratory measurements on meteorites and Apollo 11 samples indicates that the surface of Vesta has a composition very similar to that of certain basaltic achondrites.

The spectral reflectivity (0.30 to 2.50 microns) of several lunar areas was measured with ground-based telescopes. A narrow absorption band centered at 0.95 micron was revealed for the first time. No other absorption bands appear in the spectrum. The reflectivity continues to rise at longer wavelengths throughout the spectral region studied. A comparison of the telescope measurements of an area 15 kilometers in diameter that includes Tranquillity Base with laboratory measurements of Apollo 11 soil samples reveals remarkable agreement, an indication that properties determined for fairly large lunar areas are relevant to local conditions. The spectra are interpretable in terms of surface mineralogy. The absorption band varies in both depth and shape and the overall slope of the curve changes with lunar area, an indication of differences in the composition and opacity of surface material. However, the lack of variety in the band position suggests there are no major differences (say, from mostly pyroxenes to mostly olivines) in the mineralogy at those sites studied.