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Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive organ damage, which can be measured using the Scleroderma Clinical Trials Consortium Damage Index (SCTC‐DI). We aimed to identify whether distinct trajectories of damage accrual exist and to determine which variables are associated with different trajectory groups. Incident cases of SSc (<2 years) were identified in the Australian Scleroderma Interest Group and Canadian Scleroderma Research Group prospective registries. Group‐based trajectory modeling was used to identify SCTC‐DI trajectories over the cohort's first 5 annual visits. Baseline variables associated with trajectory membership in a univariate analysis were examined in multivariable models. A total of 410 patients were included. Three trajectory groups were identified: low (54.6%), medium (36.2%), and high (10.3%) damage. Patients with faster damage accrual had higher baseline SCTC‐DI scores. Older age (odds ratio [OR] 1.57 [95% confidence interval (95% CI) 1.18–2.10]), male sex (OR 2.55 [95% CI 1.10–5.88]), diffuse disease (OR 6.7 [95% CI 2.57–17.48]), tendon friction rubs (OR 5.4 [95% CI 1.86–15.66]), and elevated C‐reactive protein level (OR 1.98 [95% CI 1.49–2.63]) increased the odds of being in the high‐damage group versus the reference (low damage), whereas White ethnicity (OR 0.31 [95% CI 0.12–0.75]) and anticentromere antibodies (OR 0.24 [95% CI 0.07–0.77]) decreased the odds. We identified 3 trajectories of damage accrual in a combined incident SSc cohort. Several characteristics increased the odds of belonging to worse trajectories. These findings may be helpful in recognizing patients in whom early aggressive treatment is necessary.

The boundary between the thermosphere and exosphere is often given the simplified description of being a separation between highly collisional continuum mechanics and a collisionless domain. The realistic smooth transition through this space has historically presented a challenge to model as the assumptions used to simplify the Boltzmann equation in fluid models are invalidated at higher altitudes. A lack of rigorous modeling of the region limits the ability to understand the dynamics of light atmospheric species. This manuscript describes the dynamics present in a two‐way coupled fluid‐particle atmospheric model extending from the mesosphere through the exosphere with a smooth transition between fluid and particle domains. This model is used to examine the coupled nature of the thermosphere and exosphere using the fluid simulation TIME‐GCM and the direct simulation Monte Carlo simulation Monaco. The coupled model allows for examination of the thermosphere circulation and exosphere transport mechanisms, as well as their impacts on the distribution of hydrogen. In this analysis, upper transport regions in the exosphere are revealed and distinguished from lower transport regions during June solstice. Furthermore, coupling allows TIME‐GCM to account for effects of lateral exospheric transport of hydrogen, altering its upper boundary condition and consequentially the spatial distribution of hydrogen throughout the thermosphere. Finally, it is asserted that a self‐consistent hydrogen exobase distribution is necessary to constrain other analytical extrapolation techniques used to predict the vertical hydrogen profile in the exosphere. Plasma interactions are excluded from this study to isolate neutral dynamics. With increasing altitude, the density of the atmosphere decreases. High above the ground, the gas can no longer be described as a continuous fluid. Instead, the motion of individual atoms is important. This transition occurs near 350–500 km (220–310 miles) in altitude, between the thermosphere and exosphere, making this region difficult to simulate. A common solution is to use a direct simulation Monte Carlo model to describe the motion of atoms in the exosphere and a fluid model to describe gas circulation in the thermosphere. However, previous studies have imposed unrealistic conditions on such combined models and not allowed the thermosphere to react to exospheric gas motion. This study describes the results of allowing a simulation of each region to be informed by the other. A focus is placed on neutral hydrogen, which comprises an increasing fraction of the gas at high altitudes, influences Earth's reaction to solar events, and undergoes atmospheric escape. With the new model, hydrogen motion in the exosphere can be fully realized. This motion affects the upper boundary of the thermospheric model and its hydrogen distribution. Finally, simplified methods for finding hydrogen density in the exosphere are compared to examine what type of errors may result. A two‐way coupled thermosphere‐exosphere model permits analysis of hydrogen's competing thermospheric circulation and exospheric transportCoupling alters TIME‐GCM's hydrogen density distribution through transport between exosphere and thermosphere modelsA self‐consistent exobase hydrogen density is needed to constrain extrapolation methods predicting exospheric densities above fluid models A two‐way coupled thermosphere‐exosphere model permits analysis of hydrogen's competing thermospheric circulation and exospheric transport Coupling alters TIME‐GCM's hydrogen density distribution through transport between exosphere and thermosphere models A self‐consistent exobase hydrogen density is needed to constrain extrapolation methods predicting exospheric densities above fluid models

Introduction: Gynaecology cancers, including ovarian (OC), endometrial (EC), and cervical (CC), are prevalent with high mortality. Sarcopenia is found in 38.7% of cancer patients, adversely affecting prognosis. Computed tomography (CT) is performed routinely in oncology, yet CT assessments of sarcopenia are not commonly used to measure prognosis. This systematic review and meta-analysis aimed to evaluate the prognostic potential of pre-treatment sarcopenia assessments on overall survival (OS) and progression free survival (PFS) in gynaecology cancer. Methodology: Four electronic databases were systematically searched from 2000 to May 2020 in English: Ovid Medline, EMBASE, Web of Science, and CINAHL plus. Titles and abstracts were screened, eligible full-texts were reviewed, and data from included studies was extracted. Meta-analyses were conducted on homogenous survival data, heterogenous data were narratively reported. Results: The initial search yielded 767 results; 27 studies were included in the systematic review (n= 4286), all published between 2015 and 2020. Meta-analysis of unadjusted results revealed a negative effect of pre-treatment sarcopenia on OS in OC (HR: 1.40, 1.20–1.64, p&lt; 0.0001) (n= 10), EC (HR: 1.42, 0.97–2.10, p= 0.07) (n= 4) and CC (HR: 1.10, 0.93–1.31, p= 0.28) (n= 5), and a negative effect on PFS in OC (HR: 1.28, 1.11–1.46, p= 0.0005) (n= 8), EC (HR: 1.51, 1.03–2.20, p= 0.03) (n= 2) and CC (HR: 1.14, 0.85–1.53, p= 0.37) (n= 2). Longitudinal analysis indicated negative effects of muscle loss on survival. Overall, there was a high risk of bias. Conclusion: Pre-treatment sarcopenia negatively affected survival in gynaecology cancers. Incorporating such assessments into cancer management may be beneficial. Heterogeneity in sarcopenia assessments makes data interpretation challenging. Further research in prospective studies is required.

In this paper, the equatorial thermosphere anomaly (ETA) is investigated using accelerometer measurements to determine whether the feature is density‐dominated, wind‐dominated, or some combination of the two. An ascending‐descending accelerometry (ADA) technique is introduced to address the density‐wind ambiguity that appears when interpreting the ETA in atmospheric drag acceleration analyses. This technique separates ascending and descending acceleration measurements to determine if a wind's directionality influences the interpretation of the observed ETA feature. The ADA technique is applied to accelerometer measurements taken from the Challenging Minisatellite Payload mission and has revealed that the ETA is primarily density‐dominated from 9:00 to 16:00 local time (LT) near 400 km altitude, with the acceleration perturbations behaving similarly between 2003 and 2004 across all seasons. This finding suggests that the perturbations in the acceleration due to in‐track wind perturbations are small compared to the perturbations due to mass density, while indicating that the formation mechanisms across these local times are similar and persistent. The results also revealed that in the terminator region at 18:00 LT the acceleration perturbations deviate appreciably between ascending and descending passes, indicating different or multiple processes occurring at this local time compared to the 9:00–16:00 LT ascribed to the ETA. These results help constrain ETA formation theories to specific local times and thermospheric property responses without the use of supplemental wind measurements, while also indicating regions where in‐track winds cannot always be neglected. Earth's thermosphere, a layer in the upper atmosphere, is a highly variable region that contributes to satellite drag in low Earth orbit. The equatorial thermosphere anomaly (ETA) is a perturbation feature that produces increases and decreases in drag accelerations across the lower latitudes of the thermosphere. Direct measurements of the thermosphere are often limited, so satellite instruments, such as accelerometers, have been used to analyze the acceleration that a satellite experiences due to atmospheric drag to indirectly measure thermospheric properties. However, the measured drag acceleration is dependent on both mass density and wind, making it difficult to determine whether a change in drag across the ETA is due to either property. This has implications on what mechanisms are responsible for its formation. This work introduces an ascending‐descending accelerometry technique to exploit the fact that while acceleration perturbations produced by mass density are independent of satellite direction, those arising from winds can either be positive or negative depending on the relative spacecraft motion. By separating satellite orbits into ascending (south‐to‐north) and descending (north‐to‐south) passes, it can be determined whether drag acceleration perturbations are due to mass density, wind, or a mixture of the two, helping constrain possible formation mechanisms. Accelerometer observations of the Equatorial Thermosphere Anomaly (ETA) cannot distinguish between in‐track density and wind perturbationsA new technique is applied to observations determining that the ETA, occurring between 9 and 16 LT, is a density‐dominated featureThe ETA demonstrates repeatable annual behavior for each season, suggesting a common and persistent formation mechanism Accelerometer observations of the Equatorial Thermosphere Anomaly (ETA) cannot distinguish between in‐track density and wind perturbations A new technique is applied to observations determining that the ETA, occurring between 9 and 16 LT, is a density‐dominated feature The ETA demonstrates repeatable annual behavior for each season, suggesting a common and persistent formation mechanism

Objective: There is a need to improve the predictability of osseointegration in implant dentistry. Current literature uses a variety of in vivo titanium (Ti) implantation models to investigate failure modes and test new materials and surfaces. However, these models produce a variety of results, making comparison across studies difficult. The purpose of this study is to validate an oral osseointegration in the Lewis rat to provide a reproducible baseline to track the inflammatory response and healing of Ti implants. Methods: Ti screws (0.76 mm Ø× 2 mm length) were implanted into the maxillary diastema of 52 adult male Lewis rats. Peri-implant tissues were evaluated 2, 7, 14, and 30 days after implantation (n= 13). Seven of the 13 samples underwent microtomographic analysis, histology, histomorphometry, and immunohistochemistry to track healing parameters. The remaining six samples underwent quantitative polymerase chain reaction (qPCR) to evaluate gene expression of inflammation and bone remodeling markers over time. Results: This model achieved a 78.5% success rate. Successful implants had a bone to implant contact (BIC)% of 68.86 ± 3.15 at 30 days on average. Histologically, healing was similar to other rodent models: hematoma and acute inflammation at 2 days, initial bone formation at 7, advanced bone formation and remodeling at 14, and bone maturation at 30. qPCR indicated the highest expression of bone remodeling and inflammatory markers 2–7 days, before slowly declining to nonsurgery control levels at 14–30 days. Conclusion: This model combines cost-effectiveness and simplicity of a rodent model, while maximizing BIC, making it an excellent candidate for evaluation of new surfaces.

Objectives: Scleroderma renal crisis is a rare but serious complication affecting 2%–15% of patients with systemic sclerosis. Despite treatment with angiotensin-converting enzyme inhibitors, outcomes for scleroderma renal crisis patients are still poor. The cellular signaling mechanisms in scleroderma renal crisis are not yet known. Mammalian target of rapamycin, comprised of the subunits mTORC1 and mTORC2, has been shown to be activated in vascular lesions of renal transplant patients with anti-phospholipid antibody syndrome. Given the similarities between the pathophysiology of scleroderma renal crisis and anti-phospholipid antibody syndrome, we hypothesized that the mammalian target of rapamycin pathway would also be activated in the renal vasculature of patients with scleroderma renal crisis.Methods: We retrospectively analyzed renal biopsies of five patients with scleroderma renal crisis in the Canadian Scleroderma Research Group cohort. Immunostaining was performed using anti-P-S6RP antibodies to evaluate the phosphorylation of mTORC1, and anti-Rictor and anti-S473 to determine activation of mTORC2.Results: Four of the five patients showed mTORC1 activation in arteriolar endothelial cells, and three of the five patients showed mTORC1 activation in the arterial endothelial cells. Two of four samples showed Rictor expression in the arteriolar and arterial endothelial cells, showing mTORC2 activation. There was no expression of mTORC1 or mTORC2 in samples from two healthy controls.Conclusion: We demonstrate that both mTORC1 and mTORC2 are activated in renal biopsies with typical histologic features of scleroderma renal crisis. Dual mammalian target of rapamycin inhibitors are currently available and in development. These findings could inform further research into novel treatment targets for scleroderma renal crisis.

Dicationic imidazolum-based ionic liquids with amino acid anions (IonL) have been proposed as a multifunctional coating for titanium dental implants, as their properties have been shown to address multiple early complicating factors while maintaining host cell compatibility. This study aims to evaluate effects of this coating on host response in the absence of complicating oral factors during the early healing period using a subcutaneous implantation model in the rat. IonLs with the best cytocompatibility and antimicrobial properties (IonL-Phe, IonL-Met) were chosen as coatings. Three different doses were applied to cpTi disks and subcutaneously implanted into 36 male Lewis rats. Rats received two implants: one coated implant on one side and an uncoated implant on the contralateral sides (n= 3 per formulation, per dose). Peri-implant tissue was evaluated 2 and 14 days after implantation with H&E staining and IHC markers associated with macrophage polarization as well as molecular analysis (qPCR) for inflammatory and healing markers. H&E stains revealed the presence of the coating, blood clots, and inflammatory infiltrate at 2 days around all implants. At 14 days, inflammation had receded with more developed connective tissue with fibroblasts, blood vessels in certain doses of coated and uncoated samples with no foreign body giant cells. This study demonstrated that IonL at the appropriate concentration does not significantly interfere with healing and Ti foreign body response. Results regarding optimal dose and formulation from this study will be applied in future studies using an oral osseointegration model.

This paper presents measurements of the amplitudes and timings of the combined, annual, and semiannual variations of thermospheric neutral density, and a comparison of these density variations with measurements of the infrared emissions from carbon dioxide and nitric oxide in the thermosphere. The density values were obtained from measurements of the atmospheric drag experienced by the Challenging Minisatellite Payload, Gravity Recovery and Climate Experiment A, Gravity field and Ocean Circulation Explorer, and three Swarm satellites, while the optical emissions were measured with the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite. These data span a time period of 16 years. A database containing global average densities that were derived from the orbits of about 5,000 objects (Emmert, 2009, https://doi.org/10.1029/2009JA014102, 2015b, https://doi.org/10.1002/2015JA021047) was employed for calibrating these density data. A comparison with the NRLMSISE‐00 model was used to derive measurements of how much the density changes over time due to these seasonal variations. It is found that the seasonal density oscillations have significant variations in amplitude and timing. In order to test the practicality of using optical emissions as a monitoring tool, the SABER data were fit to the measured variations. Even the most simple fit that used only filtered carbon dioxide emissions had good correlations with the measured oscillations. However, the density oscillations were also well predicted by a simple Fourier series, contrary to original expectations. Nevertheless, measurements of the optical emissions from the thermosphere are expected to have a role in future understanding and prediction of the semiannual variations. The uppermost atmosphere, known as the thermosphere, undergoes oscillations in the density of the neutral atoms and molecules, producing two peaks and valleys in the density in each year. The timing of of these “semiannual” variations or oscillations, as well as their amplitudes, tends to vary. Their unpredictability makes it harder to accurately model the amount of drag experienced by orbiting satellites. It had been noticed that the infrared light emitted by carbon dioxide molecules in the thermosphere has a tendency to follow the semiannual oscillations. Such emissions have been measured by an instrument on a NASA satellite for the past 16 years. We have compared these emissions with the variations in the semiannual oscillations that were derived from measurements of the drag seen by six different satellites flown by both NASA and the European Space Agency during the same time period, though not at the same time. The results of the comparison show how well the infrared emissions match the density oscillations, due to changes in both the composition and temperature of the thermosphere that influence both. Results show that further study will be needed to be able to accurately predict the density oscillations. Four satellite missions are used to derive thermosphere density variations caused by annual and semiannual oscillations over a 16‐year periodVariations in thermospheric density are compared with emissions from carbon dioxide and nitric oxide measured with the SABER instrumentThe carbon dioxide emissions and simple Fourier series fits have good correlations with thermosphere density oscillations

Polar cap neutral density anomaly (PCNDA) with large mass density enhancements over the background has been frequently observed in the polar cap during magnetic storms. By tracing field lines to the magnetosphere from the polar ionosphere, we divide the polar cap into two regions, an open field line (OFL) region with field lines connecting to the magnetopause boundary and a distant tail field line (TFL) region threaded with magnetotail lobe field lines. A statistical study of neutral density observed by the Challenging Minisatellite Payload satellite during major magnetic storms with Dst< −100 from July 2001 to 2006 indicates that over 85% of density anomalies were detected in the TFL region, at about 18° to 25° equatorward the center of the OFL region. PCNDAs were frequently accompanied by plasma clouds with peak density greater than 105#/cm3. Modeling of plasma cloud drift paths suggests that plasma clouds originating in the dayside ionosphere could convect through the OFL region following the zero‐potential line and reach the PCNDA locations. Plasma clouds could become stagnate in the TFL region, allowing a long duration of collisions with the neutral gas and possibly contributing to heating of PCNDAs. The PCNDA observations are interpreted as evidence that traveling atmospheric disturbance could be generated in the nightside polar cap. From the PCNDA size and speed of sound at 400 km, we derive an initial energy deposition duration for producing traveling atmospheric disturbance in the range from 0.5 to 2.5 hr. Polar cap neutral density anomaly occurs frequently between the open‐closed field line boundary (OCB) and the nightside auroral zoneThe polar cap neutral density anomaly sizes suggest an energy deposition duration for producing TADs in the range from 0.5 to 2.5 hrDensity anomalies are frequently accompanied by plasma clouds originating from the dayside ionosphere or the vicinity of the dayside cusp

Body concealment is a component of social avoidance among people with visible differences from disfiguring conditions, including systemic sclerosis (SSc). The study objective was to develop a measure of body concealment related to avoidance behaviors in SSc. Initial items for the Body Concealment Scale for Scleroderma (BCSS) were selected using item analysis in a development sample of 93 American SSc patients. The factor structure of the BCSS was evaluated in 742 Canadian patients with single‐factor, 2‐factor, and bifactor confirmatory factor analysis models. Convergent and divergent validity were assessed by comparing the BCSS total score with the Brief‐Satisfaction with Appearance Scale (Brief‐SWAP) and measures of depressive symptoms and pain. A 2‐factor model (Comparative Fit Index [CFI] 0.99, Tucker‐Lewis Index [TLI] 0.98, Root Mean Square Error of Approximation [RMSEA] 0.08) fit substantially better than a 1‐factor model (CFI 0.95, TLI 0.94, RMSEA 0.15) for the 9‐item BCSS, but the Concealment with Clothing and Concealment of Hands factors were highly correlated (α = 0.79). The bifactor model (CFI 0.99, TLI 0.99, RMSEA 0.08) also fit well. In the bifactor model, the omega coefficient was high for the general factor (ω = 0.80), but low for the Concealment with Clothing (ω = 0.01) and Concealment of Hands (ω = 0.33) factors. The BCSS total score correlated more strongly with the Brief‐SWAP Social Discomfort (r = 0.59) and Dissatisfaction with Appearance (r = 0.53) subscales than with measures of depressive symptoms and pain. The BCSS sum score is a valid indicator of body concealment in SSc that extends the concepts of body concealment and avoidance beyond the realms of body shape and weight to concerns of individuals with visible differences from SSc.

Married persons have, on average, better mental health than nonmarried persons. Among married persons, marital satisfaction is associated with better mental health. Studies on mental health in married and nonmarried persons that consider marital satisfaction have categorized patients as satisfied versus unsatisfied, which reduces statistical power and does not generate clinically useful information on mental health across the satisfaction spectrum. Our objective was to demonstrate a novel regression approach to evaluate mental health in women with systemic sclerosis (SSc), comparing married and unmarried women, accounting for continuously measured marital satisfaction. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES‐D) and marital satisfaction with the Dyadic Adjustment Scale‐7. A single multiple linear regression model was used to predict CES‐D scores from marital status and, among married women, continuously measured marital satisfaction, controlling for demographic and clinical characteristics. Of 725 women, 494 (68%) were married or living as married. On average, married women had mean CES‐D scores that were 2.0 points (0.19 SDs) lower than unmarried women (P= 0.013). Among married women, a 1.0 SD increase in marital satisfaction was associated with a 2.2 point (0.21 SDs) decrease in CES‐D scores (P< 0.001). Married women whose marital satisfaction scores were below the 19th percentile had greater predicted depressive symptoms than unmarried women. Married women's predicted CES‐D scores ranged from 6.7 points lower to 6.9 points higher than those of unmarried women, depending on marital satisfaction. Comparisons of mental health in married and unmarried patients with rheumatic diseases should include continuously measured marital satisfaction.

This paper describes a technique for mapping exospheric temperatures, derived from neutral density measurements from the Challenging Mini-satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE) satellites. The Naval Reasearch Laboratory Mass Spectrometer, Incoherent Scatter Radar Extended Model (NRLMSISE-00) thermosphere model is used for the conversion. Adjustments for each satellite were needed in order for the time-averaged densities to agree with the model. It was necessary to correct for inexact modeling of the annual and semiannual oscillations in the density, as well as the declining densities during the solar minimum. It was found that a time-varying perturbation in the atomic oxygen in the model could produce a good agreement at both altitudes. The time series of this oxygen variation was found to have a very high correlation with independent measurements of CO2emissions measured with the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument. The temperature data are averaged on a spherical grid having equal areas in each pixel, avoiding functional fits that would blur finer details. The use of solar magnetic rather than geographic coordinates enhances the auroral ovals. There are strong elevations in the exospheric temperatures in the polar regions, particularly near the dayside cusp. Spatial filtering with spherical wavelets is used to remove statistical fluctuations, although some details are lost. The exospheric temperature maps are well ordered by the nitric oxide emission measurements from SABER. The technique that is described here could be applied to future improvements of empirical density models, having an accuracy and spatial resolution that is not presently available. A technique is described for mapping exospheric temperatures from density measurements, using a spherical, equal-area gridThe NRLMSISE-00 thermosphere density model is used to cross-calibrate accelerometer-inferred densities from multiple satellitesAtomic oxygen adjustments in the model, with annual and semiannual oscillations, are found to correlate with measured optical emissions

The intraseasonal variability of the eastward propagating nonmigrating diurnal tide with zonal wave number 3 (DE3) during 2007 in the mesosphere, ionosphere, and thermosphere is investigated using a whole atmosphere model reanalysis and satellite observations. The atmospheric reanalysis is based on implementation of data assimilation in the Whole Atmosphere Community Climate Model (WACCM) using the Data Assimilation Research Testbed (DART) ensemble Kalman filter. The tidal variability in the WACCM+DART reanalysis is compared to the observed variability in the mesosphere and lower thermosphere (MLT) based on the Thermosphere Ionosphere Mesosphere Energetics Dynamics satellite Sounding of the Atmosphere using Broadband Emission Radiometry (TIMED/SABER) observations, in the ionosphere based on Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) observations, and in the upper thermosphere (∼475 km) based on Gravity Recovery and Climate Experiment (GRACE) neutral density observations. To obtain the short‐term DE3 variability in the MLT and upper thermosphere, we apply the method of tidal deconvolution to the TIMED/SABER observations and consider the difference in the ascending and descending longitudinal wave number 4 structure in the GRACE observations. The results reveal that tidal amplitude changes of 5–10 K regularly occur on short timescales (∼10–20 days) in the MLT. Similar variability occurs in the WACCM+DART reanalysis and TIMED/SABER observations, demonstrating that the short‐term variability can be captured in whole atmosphere models that employ data assimilation and in observations by the technique of tidal deconvolution. The impact of the short‐term DE3 variability in the MLT on the ionosphere and thermosphere is also clearly evident in the COSMIC and GRACE observations. Analysis of the troposphere forcing in WACCM+DART and simulations of the Global Scale Wave Model (GSWM) show that the short‐term DE3 variability in the MLT is not related to a single source; rather, it is due to a combination of changes in troposphere forcing, zonal mean atmosphere, and wave‐wave interactions. Short‐term DE3 variability in observations is compared with WACCM+DART reanalysisShort‐term variability found to occur in MLT, ionosphere, and upper thermosphereSeveral different mechanisms combine to generate the short‐term variability

We present ISO LWS and SWS spectra of far-infrared (FIR) atomic fine structure lines in 12 carbon-rich evolved stars including asymptotic giant branch (AGB) stars, proto-planetary nebulae (PPNe) and planetary nebulae (PNe). The spectra include grating and Fabry-Perot measurements of the line emission of [Oi], [Cii], [Sii], [Siii], [Si], [Fei], [Feii], [Neii] and [Nii]. Only 5 out of our 12 object sample have been detected in at least one of these FIR lines. When we include the 12 oxygen-rich evolved stars from Castro-Carrizo et al. ([CITE], Paper II), we find that atomic line emission is observed only in those sources in which the central star's Teff≥10 000 K. Above this cutoff, the number of detectable lines and the intensity of the line emission increase as Teffincreases. These trends suggest that the atomic lines originate from photodissociation regions (PDRs). In general, the kinematics of the atomic gas, derived from line fits to the Fabry-Perot data, are comparable to the molecular expansion velocities. These kinematics are expected for atomic cooling lines associated with circumstellar PDRs. AFGL 618, however, appears exceptional with dual velocity components: a narrow component (<20 km s-1) that may be associated with a PDR, and a broad component (∼66 km s-1) that may be produced in post-shocked, accelerated gas. A new PDR code which properly treats enhanced carbon abundances was used to model the observations of our carbon-rich objects. The predicted line intensities agree reasonably well with the observations. Shock models, however, do not compare well with the observed line intensities. PDR mass estimates ranging from ∼0.01-0.2 $M_\odot$were derived from the [Cii] 158 μm line emission. The atomic gas constitutes only a small fraction of the total mass for young planetary nebulae, but its importance grows significantly as the nebulae evolve. Our overall analysis shows that photodissociation, and not shocks, dominates the evolution of the circumstellar envelope by transforming the initially molecular asymptotic giant branch envelopes into the atomic gas found in proto-planetary and planetary nebulae.

Water vapor in the Earth's troposphere produces fluctuations in the phase of millimeter-wavelength radiation from astronomical sources. Such fluctuations seriously limit the spatial resolution achievable with current millimeter interferometers. Since water vapor is also a source of atmospheric opacity at these wavelengths, radiometric measurements of sky brightness may be used to monitor the fluctuating water vapor content of the atmosphere and thereby the fluctuations in the interferometric phase. The atmospheric opacity depends on the frequency and on the physical conditions of those atmospheric regions in which the water vapor is located. Atmospheric temperature influences the strengths of the various absorption lines, and pressure influences the degree of line broadening. The magnitude of the phase fluctuations relative to the brightness fluctuations is therefore also dependent on frequency, temperature, and pressure. The frequency of a radiometric monitoring system may be chosen to minimize the dependence of this ratio on the atmospheric parameters.

We exploit a recently developed technique, based on ion‐neutral coupling, which allows estimations of the upper thermospheric neutral density using measurements of ionospheric plasma parameters made by the European Incoherent Scatter (EISCAT) Svalbard Radar (ESR). The technique is applied to a 13 year long data set of measurements for the purpose of studying and quantifying the effect of solar activity on the upper thermospheric density inside the polar cap. We concentrate on the effect of solar activity at 350 km altitude and find a strong linear correlation between the ESR estimates for the atomic oxygen density and the solar irradiance proxy F10.7index. We use the relationship to isolate variations in the thermospheric density that are present after solar activity influences are removed. Our results show a decrease in the density of a few percent over the 13 year period, which is nevertheless smaller than the uncertainty associated with the decline. We anticipate that the statistical significance of this result will only increase by studying a longer data set. Conjunctions with the CHAMP satellite that show very good agreement is achieved at 350 km especially during low solar activity. Thermospheric density estimates using incoherent scatter radarSolar cycle influence on thermospheric density in the polar capPossible indications of decadal‐scale decline in density

Objective.To develop and validate, as a measure of overall health status, a Frailty Index (FI) for patients (n = 1372) in the Canadian Scleroderma Research Group (CSRG) Registry.Methods.Forty-four items were selected from the CSRG database as health deficits and recoded using FI criteria. To test construct validity, we compared measurement properties of the CSRG-FI to other FI, and related it to measures of damage, age, and time since diagnosis. To test criterion validity, we compared the baseline FI to that at last recorded visit and to mortality.Results.The mean CSRG-FI was 0.33 with a sub-maximal limit of 0.67. In patients with diffuse disease, the mean was 0.38(SD 0.14); in patients with limited disease, the mean was 0.31(SD 0.13). The CSRG-FI was weakly (but significantly) correlated with the Rodnan Skin Score (r = 0.28 in people with diffuse disease; 0.18 with limited) and moderately with the Physician Assessment of Damage (r = 0.51 for both limited and diffuse). The risk of death increased with higher FI scores and with higher physician ratings of damage. The area under the receiver operating characteristic curve for the baseline FI in relation to death was 0.75, higher than for other measures (range: 0.57–0.67).Conclusion.The FI quantifies overall health status in people with scleroderma and predicts mortality. Whether the FI might help with decisions about who might best be served by more aggressive treatment, such as bone marrow transplantation, needs to be evaluated.

Objective.Antinuclear antibodies (ANA) occur in up to 95% of patients with systemic sclerosis (SSc). In most, SSc-associated antibodies are detected (i.e., centromere, topoisomerase I, RNA polymerase III, PM/Scl, Ro52/TRIM21, and U1RNP). Ribonuclease P protein subunit p25, (Rpp25) is an autoantigenic component of the Th/To complex. The contribution of anti-Th/To and anti-Rpp25 antibodies to ANA positivity in patients with SSc remains unknown.Methods.Sera from 873 patients with SSc were tested for ANA, and SSc-associated antibodies were measured. Samples without antibodies to extractable nuclear antigens (ENA; n = 53, ANA+/ENA−), were analyzed by immunoprecipitation (IP) and metabolically labeled proteins and for anti-Rpp25 antibodies (n = 50) by a chemiluminescent immunoassay (CLIA) and Rpp25 ELISA.Results.Anti-Th/To antibodies occurred in 19/53 (36%), as determined by IP, and were the most common autoantibody in ANA+/ENA− SSc. Of those samples, 50/53 were available for additional testing by CLIA and ELISA. Anti-Rpp25 antibodies were detected in 12 (24% CLIA) or 10 (20% ELISA) of 50 patients. Receiver-operating characteristic curve analysis showed similar discrimination between Th/To IP-positive (n = 19) and -negative samples (n = 31) by CLIA and ELISA (area under the curve 0.90 vs 0.87; p = 0.6691). The positive percent agreement between IP and CLIA or ELISA was 12/19 (63.2%, 95% CI 38.4–83.7%) or 10/19 (52.6%, 95% CI 73.3–94.2%), respectively. Negative percent agreement was 100% for both assays.Conclusion.Autoantibodies to the Th/To autoantigen are important in patients with SSc who have been considered negative for SSc-specific or SSc-associated antibodies by widely available commercial assays. Rpp25 can be considered a major target of anti-Th/To antibodies. Assays detecting anti-Th/To and anti-Rpp25 antibodies may be important in SSc.

Objective.To describe the clinical and serological features of systemic sclerosis sine scleroderma (ssSSc) in a multicentered SSc cohort.Methods.Data from 1417 subjects in the Canadian Scleroderma Research Group registry were extracted to identify subjects with ssSSc, defined as SSc diagnosed by an expert rheumatologist, but without any sclerodactyly or skin involvement prior to baseline study visit or during followup. Clinical and serological features of ssSSc subjects were compared to limited (lcSSc) and diffuse cutaneous SSc (dcSSc) subjects.Results.At the first registry visit, only 57 subjects (4.0%) were identified as having ssSSc. Of these, 30 (2.1%) were reclassified as lcSSc within 1.9 years. Thus, only 27 ssSSc subjects (1.9%) remained, with mean followup of 2.4 years. Clinical profiles of ssSSc were generally similar or milder compared to lcSSc, and milder than dcSSc, including rates of interstitial lung disease (25.9% ssSSc, 25.4% lcSSc, 40.3% dcSSc). Patients with ssSSc had serological profiles similar to those with lcSSc, including high rates of anticentromere antibodies (50.0% ssSSc, 47.5% lcSSc, 12.1% dcSSc), and low rates of antitopoisomerase I (16.7% ssSSc, 7.0% lcSSc, 21.8% dcSSc) and anti-RNA polymerase III (0 ssSSc, 11.1% lcSSc, 34.9% dcSSc).Conclusion.The condition ssSSc is rare and resembles lcSSc. These observations suggest that ssSSc is most likely a forme fruste of lcSSc, and that the absence of skin involvement may in part be related to misclassification arising from early or subtle skin involvement. There is little evidence to consider ssSSc as a distinct clinical or serological subset of SSc.