Introduction: Early identification of preventable risk factors of COPD progression is important. Whether exacerbations have a negative impact on disease progression is largely unknown. We ...investigated whether the long-term occurrence of exacerbations is associated with lung function decline at early stages of COPD. Methods: Patients diagnosed with mild/moderate COPD (obstruction and FEV.sub.1% predicted 50-90%), aged greater than or equal to35 years, and a smoking history, who had greater than or equal to6 years of UK electronic medical records after initiation of maintenance therapy were studied. Multilevel mixed-effect linear regression was performed to determine the association between the count of any year in which the patient had greater than or equal to1 exacerbation over a 6-year period and FEV.sub.1 decline, adjusted for sex, age, anthropometrics and smoking habits. Exacerbations were defined as any prescription for an acute oral corticosteroid course and/or lower respiratory-related antibiotics and/or any COPD-related emergency or inpatient hospitalization. Results: Of 11,337 patients included (mean age 65 years; 49% female) 31.6%, 23.3%, 16.6%, 11.6%, 8.1%, 5.3% and 3.4% had 0, 1, 2, 3, 4, 5 and 6 years with greater than or equal to1 exacerbation. The mean annual FEV.sub.1 decline accelerated by 1.50 mL/year (95% Confidence Interval 1.02; 1.98) with every additional year with greater than or equal to1 exacerbation from 31.0 mL/year in subjects without any exacerbation to 40.0 mL/year in patients experiencing greater than or equal to1 exacerbation every year. Patients with more years with greater than or equal to1 exacerbation had a lower mean FEV.sub.1 at first diagnosis: 14.7 mL (11.7; 17.8) lower with every additional year with exacerbations. When counting years with greater than or equal to2 exacerbations, greater effects were observed (2.19 1.50; 2.88 mL/year excess decline per year with greater than or equal to2 exacerbations; 16.5 mL 12.1; 20.8 lower FEV.sub.1 at diagnosis). Conclusion: Patients who experienced a greater exacerbation burden after initiation of maintenance therapy had worse lung function at diagnosis and a more rapid lung function decline thereafter, which emphasizes the need for better treatment strategies. Keywords: COPD, exacerbations, spirometry, inhalation therapy, observational study
On 9 October 2009 the Lunar Crater Observation and Sensing Satellite (LCROSS) impacted Cabeus crater, located near the south pole of the Moon. Prior to that impact, the Mini‐RF instruments on ISRO's ...Chandrayaan‐1 and NASA's Lunar Reconnaissance Orbiter (LRO) obtained S band (12.6 cm) synthetic aperture radar images of the impact site at 150 and 30 m resolution, respectively. These observations show that the floor of Cabeus has a circular polarization ratio (CPR) comparable to or less than the average of nearby terrain in the southern lunar highlands. Furthermore, <2% of the pixels in Cabeus crater have CPR values greater than unity. This observation is not consistent with the presence of thick deposits of nearly pure water ice within a few meters of the lunar surface, but it does not rule out the presence of small (<∼10 cm), discrete pieces of ice mixed in with the regolith. In addition, Mini‐RF on LRO acquired a postimpact S band image of the region surrounding the LCROSS impact site, providing important geologic context for the site. Registering the LRO image to a near‐infrared (NIR) image taken by the LCROSS shepherding spacecraft, we find that the impactor landed in the ray of a fresh, radar‐bright, 1 km crater. However, the difference between preimpact and postimpact images is not above the speckle noise. This implies that the size of the LCROSS impact crater is less than Mini‐RF's resolution (30 m), and/or that the impact did not excavate more decimeter‐size blocks than were already present at the impact site.
A number of soybean varieties traditionally bred for resistance to various soybean arthropod pests have been identified as resistant to Megacopta cribraria (F.) (Hemiptera: Plataspidae). However, the ...mechanisms of host-plant resistance (HPR) in this system are not understood. The goal of this study was to identify the mechanisms of resistance by examining the role of plant volatile organic compounds (VOCs) and free amino acids (FAAs) among 16 soybean varieties. Choice and no-choice cage experiments identified several soybean varieties that demonstrated antixenosis as well as antibiosis. However, resistance varied over time in certain soybean varieties, such as N02-7002 and PI567352B. Mean nymph number from choice experiments had positive correlations with the FAAs asparagine, tryptophan, alanine, phenylanaline, and serine; negative correlation with leucine and threonine. Four plant volatiles, hexanal, 2-pentylfuran, beta-cyclocitral, and cis-9-hexadecenal, were positively correlated with subsequent nymph development, whereas n-hexadecenoic acid was negatively correlated with nymph number only, in adult choice cage experiments. This study contributes to understanding the mechanisms of HPR through associations with plant VOCs and FAAs in relation to M. cribraria development and provides useful knowledge for developing soybean varieties for M. cribraria management.
We present four new exoplanets: HIP 14810b and HIP 14810c, HD 154345b, and HD 187123c. The two planets orbiting HIP 14810, from the N2K project, have masses of 3.9 and 0.76 M sub(J). We have searched ...the radial velocity time series of 90 known exoplanet systems and found new residual trends due to additional, long period companions. Two stars known to host one exoplanet have sufficient curvature in the residuals to a one planet fit to constrain the minimum mass of the outer companion to be substellar: HD 68988c with 8 M sub(J) < m sin i < 20 M sub(J) and HD 187123c with 3 M sub(J) < m sin i < 7 M sub(J), both with P > 8 yr. We have also searched the velocity residuals of known exoplanet systems for prospective low-amplitude exoplanets and present some candidates. We discuss techniques for constraining the mass and period of exoplanets in such cases, and for quantifying the significance of weak RV signals. We also present two substellar companions with incomplete orbits and periods longer than 8 yr: HD 24040b and HD 154345b with m sin i < 20 M sub(J) and m sin i < 10 M sub(J), respectively.
ABSTRACT
The early, active history of our Sun is still not fully understood. Observations of the magnetic fields on active young solar-type stars allow us an insight into the early evolution of our ...Sun. Here we present Doppler and Zeeman–Doppler images of the young late-F star HIP 71933 (HD 129181) at multiple epochs to add to the growing data about the evolution of magnetic cycles in solar-type stars. Spectroscopic data were obtained over seven epochs spanning 10 yr of observations, with two epochs including spectropolarimetric data. The brightness maps at all epochs show a consistent spot activity in a non-uniform ring at a latitude of approximately +60° with no polar spot present in any epoch. The two magnetic field maps taken ∼2 yr apart show a strong poloidal field configuration with most of the poloidal field energy in the dipolar configuration. The magnetic maps show no evidence of a polarity reversal. We were able to measure the differential rotation from one of the seven epochs using the brightness data finding a dΩ of 0.325 ± 0.01 rad d−1. The values for the rotational period and differential rotation found for HIP 71933 are consistent with values found for other late-F or early-G stars. The dominant poloidal features and the limited spots at the pole are unusual for a rapidly rotating star but not unique.
Megacopta cribraria (F.) (Hemiptera: Plataspidae) is an invasive pest of soybean that has spread across the southeastern United States since its initial discovery in 2009 in Georgia. Previous studies ...in the southeastern states have documented both the population dynamics of this pest and host plant resistance (HPR) among soybean varieties, although the specific mechanisms of HPR remain unknown. The objectives of this study were, therefore, to 1) quantify field resistance to M. cribraria in multiple soybean varieties in two states previously affected by severe M. cribraria infestations, North Carolina (NC) and South Carolina (SC); and 2) study the role of soybean trichome density in imparting resistance against M. cribraria. Soybean variety ‘Camp’ was least attractive to M. cribraria, through time and locations, suggesting consistent resistance. Other varieties showed variable performance among the locations and sampling dates. A significant difference in trichome density was evident. However, there was no correlation between trichome density and M. cribraria infestation. Compared to a previously published study in the same location, when M. cribraria adults emerging from overwintering dispersed into soybeans, in our study only first-generation adults dispersed into soybeans. Considering the current trend of significantly lower M. cribraria infestation rates in North and South Carolina, this pest may be finally succumbing to indigenous natural enemies and should be managed by incorporating integrated pest management tactics, such as HPR, that help conserve natural enemy populations.
We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period ...of 6005 + or - 427 days, and a minimum mass of 5.3 M sub(Jup). HD 142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 + or - 0.07). The second planet in the HD 159868 system has a period of 352.3 + or - 1.3 days and m sin i = 0.73 + or - 0.05 M sub(Jup). In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems.
Determining the orbital eccentricity of an extrasolar planet is critically important for understanding the system's dynamical environment and history. However, eccentricity is often poorly determined ...or entirely mischaracterized due to poor observational sampling, low signal-to-noise, and/or degeneracies with other planetary signals. Some systems previously thought to contain a single, moderate-eccentricity planet have been shown, after further monitoring, to host two planets on nearly circular orbits. We investigate published apparent single-planet systems to see if the available data can be better fit by two lower-eccentricity planets. We identify nine promising candidate systems and perform detailed dynamical tests to confirm the stability of the potential new multiple-planet systems. Finally, we compare the expected orbits of the single- and double-planet scenarios to better inform future observations of these interesting systems.
The purpose of this study was to determine the efficacy of stent-based delivery of sirolimus (SRL) alone or in combination with dexamethasone (DEX) to reduce in-stent neointimal hyperplasia. SRL is a ...potent immunosuppressive agent that inhibits SMC proliferation by blocking cell cycle progression.
Stents were coated with a nonerodable polymer containing 185 microgram SRL, 350 microgram DEX, or 185 microgram SRL and 350 microgram DEX. Polymer biocompatibility studies in the porcine and canine models showed acceptable tissue response at 60 days. Forty-seven stents (metal, n=13; SRL, n=13; DEX, n=13; SRL and DEX, n=8) were implanted in the coronary arteries of 16 pigs. The tissue level of SRL was 97+/-13 ng/artery, with a stent content of 71+/-10 microgram at 3 days. At 7 days, proliferating cell nuclear antigen and retinoblastoma protein expression were reduced 60% and 50%, respectively, by the SRL stents. After 28 days, the mean neointimal area was 2.47+/-1.04 mm(2) for the SRL alone and 2.42+/-1.04 mm(2) for the combination of SRL and DEX compared with the metal (5.06+/-1.88 mm(2), P<0.0001) or DEX-coated stents (4.31+/-3.21 mm(2), P<0.001), resulting in a 50% reduction of percent in-stent stenosis.
Stent-based delivery of SRL via a nonerodable polymer matrix is feasible and effectively reduces in-stent neointimal hyperplasia by inhibiting cellular proliferation.
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