Hybrid cloud and error masking to improve the quality of deterministic satellite sea surface temperature retrieval and data coverage

AbstractIn the infrared region, the quality of sea surface temperature (SST) retrievals critically depends on the cloud detection scheme. More than 5 million matchups, where the surface and top of atmosphere measurements are available, have been carefully analyzed to understand clouds related errors and to develop the advanced cloud detection scheme for improvement of satellite SST quality. The effectiveness of a Bayesian cloud detection (BCD) scheme, operationally implemented at the NOAA Office of Satellite Product Operations (OSPO) for the GOES-Imager, has been examined using an experimental filter and it is found that this scheme is not optimal. Thus, a new algorithm for cloud and error masking (CEM) scheme is proposed for physical SST retrievals. This is based on a quasi-deterministic approach combined with an approximated radiative transfer model and the functional spectral differences at pixel level. Although, traditionally the validation of cloud detection algorithms have often been reported qualitatively using visual inspection of imagery, we have made a quantitative validation of the cloud algorithm for its intended purpose by determining the quality of satellite SST retrievals against in situ data. Results show that CEM can reduce the root mean square error in SST by an average of 22% while increasing the data coverage by an average of 38% compared to the operationally implemented BCD at OSPO, as assessed over a period of fifty months

RP-HPLC METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF CLINDAMYCIN PHOSPHATE AND CLOTRIMAZOLE IN PHARMACEUTICAL DOSAGE FORMS

Objective: The aim of this work was to develop and validate a simple Reverse Phase-High Performance Liquid Chromatography method for the simultaneous estimation of Clindamycin and Clotrimazole in pharmaceutical dosage forms.Methods: The mobile phase consists of phosphate buffer and Acetonitrile in the ratio of (48:52) with gradient programming, Hypersil BDS (250×4.6 mm,5µ) column used as stationary phase with a flow rate of 1 ml/min, injection volume 10 µl and the run time was 10 min. Detection wavelength was at 220 nm by using Photo Diode Array detector.Results: The retention times of Clindamycin and Clotrimazole were found to be 2.2 min and 5.7 min respectively. The method was validated according to ICH guidelines. Validation parameters like accuracy, precision, linearity, range, limit of detection, limit of quantification and robustness all were within the limits. The linearity responses of Clindamycin and Clotrimazole were found to be in the concentration ranges of 25-150 µg/ml and 50-300 µg/ml. The percentage recovery for both drugs was found in the range of 99-100%. The LOD & LOQ values for were found to be 1.29µg/ml and 3.93µg/ml and Clotrimazole were found to be 1.31µg/ml and 3.96 µg/ml, respectively.Conclusion: The results obtained are accurate and within the limits. Hence this method can be applicable for the estimation of Clindamycin and Clotrimazole in pharmaceutical dosage forms.Â

The actual Rees--Sciama effect from the Local Universe

Observations of the Cosmic Microwave Background (CMB) have revealed an unexpected quadrupole-octopole alignment along a preferred axis pointing toward the Virgo cluster. We here investigate whether this feature can be explained in the framework of the concordance model by secondary anisotropies produced by the non-linear evolution of the gravitational potential, the so-called Rees-Sciama (RS) effect. We focus on the effect caused by the local superclusters, which we calculate using a constrained high-resolution hydrodynamical simulation, based on the IRAS 1.2-Jy all-sky galaxy redshift survey, which reproduces the main structures of our Universe out to a distance of 110 Mpc from our Galaxy. The resulting RS effect peaks at low multipoles and has a minimum/maximum amplitude of -6.6\mu K 1.9\mu K. Even though its quadrupole is well aligned with the one measured for the CMB, its amplitude is not sufficient to explain the observed magnitude of the quadrupole/octopole alignment. In addition, we analyze the WMAP-3 data with a linear matched filter in an attempt to determine an upper limit for the RS signal amplitude on large scales. We found that it is possible to infer a weak upper limit of 30\mu K for its maximum amplitude.Comment: 7 pages, 4 figures, submitted to A&

Prospective randomized subject-masked study of intravitreal bevacizumab monotherapy versus dexamethasone implant monotherapy in the treatment of persistent diabetic macular edema

Purpose: To compare intravitreal bevacizumab monotherapy with intravitreal dexamethasone delayed delivery system monotherapy for persistent diabetic macular edema. Methods: Single-center, randomized, subject-masked study of eyes with persistent diabetic macular edema, defined as central subfield thickness (CST) >340 μm despite ≥3 anti–vascular endothelial growth factors injections within 5 months. The intravitreal bevacizumab monotherapy (n = 23 eyes) and delayed delivery system monotherapy (n = 27 eyes) groups received treatments q1month and q3months, respectively. Results: Baseline best-corrected visual acuity and CST were similar in the two groups. At Month 7, the mean final best-corrected visual acuity (mean ± SD) was 65 ± 16 letters (mean Snellen visual acuity 20/50) and 64 ± 11 letters (20/50) (P = 0.619), the mean change in best-corrected visual acuity was +5.6 ± 6.1 and +5.8 ± 7.6 letters (P = 0.785), the mean final CST was 471 ± 157 and 336 ± 89 μm (P = 0.001), and the mean change in CST was −13 ± 105 and −122 ± 120 μm (P = 0.005) in the intravitreal bevacizumab monotherapy and delayed delivery system monotherapy groups, respectively. The number of injections was 7.0 ± 0.2 and 2.7 ± 0.5 (P < 0.001) in the 2 groups. Conclusion: The two groups had similar best-corrected visual acuity gains. The delayed delivery system monotherapy group achieved a significantly greater reduction of CST compared with the intravitreal bevacizumab monotherapy group, with a q3month interval of treatment, and had no recurrent edema at any visit

Long-Term Use of Intravitreal Bevacizumab (Avastin) for the Treatment of Von Hippel-Lindau Associated Retinal Hemangioblastomas

Retinal hemangioblastomas are the most common manifestation of Von Hippel-Lindau (VHL) disease [1-3]. While peripheral retinal hemangioblastomas may be treated by thermal laser treatment or cryotherapy, optic nerve and macular lesions are more difficult to treat [4, 5]. Based on the theoretical benefit of administering anti-VEGF treatment, intra-vitreally administered bevacizumab (Avastin, a general pan-VEGF inhibitor) is attractive [6, 7]

An optimal filter for the detection of galaxy clusters through weak lensing

We construct a linear filter optimised for detecting dark-matter halos in weak-lensing data. The filter assumes a mean radial profile of the halo shear pattern and modifies that shape by the noise power spectrum. Aiming at separating dark-matter halos from spurious peaks caused by large-scale structure lensing, we model the noise as being composed of weak lensing by large-scale structures and Poisson noise from random galaxy positions and intrinsic ellipticities. Optimal filtering against the noise requires the optimal filter scale to be smaller than typical halo sizes. Although a perfect separation of halos from spurious large-scale structure peaks is strictly impossible, we use numerical simulations to demonstrate that our filter produces substantially more sensitive, reliable and stable results than the conventionally used aperture-mass statistic.Comment: 9 pages, 6 figures, A&A submitte

The importance of the merging activity for the kinetic polarization of the Sunyaev-Zel'dovich signal from galaxy clusters

The polarization sensitivity of the upcoming millimetric observatories will open new possibilities for studying the properties of galaxy clusters and for using them as powerful cosmological probes. For this reason it is necessary to investigate in detail the characteristics of the polarization signals produced by their highly ionized intra-cluster medium (ICM). This work is focussed on the polarization effect induced by the ICM bulk motions, the so-called kpSZ signal, which has an amplitude proportional to the optical depth and to the square of the tangential velocity. In particular we study how this polarization signal is affected by the internal dynamics of galaxy clusters and what is its dependence on the physical modelling adopted to describe the baryonic component. This is done by producing realistic kpSZ maps starting from the outputs of two different sets of high-resolution hydrodynamical N-body simulations. The first set (17 objects) follows only non-radiative hydrodynamics, while for each of 9 objects of the second set we implement four different kinds of physical processes. Our results shows that the kpSZ signal turns out to be a very sensitive probe of the dynamical status of galaxy clusters. We find that major merger events can amplify the signal up to one order of magnitude with respect to relaxed clusters, reaching amplitude up to about 100 nuK. This result implies that the internal ICM dynamics must be taken into account when evaluating this signal because simplicistic models, based on spherical rigid bodies, may provide wrong estimates. Finally we find that the dependence on the physical modelling of the baryonic component is relevant only in the very inner regions of clusters.Comment: 13 pages, 7 figures, submitted to A&

Testing the reliability of weak lensing cluster detections

We study the reliability of dark-matter halo detections with three different linear filters applied to weak-lensing data. We use ray-tracing in the multiple lens-plane approximation through a large cosmological simulation to construct realizations of cosmic lensing by large-scale structures between redshifts zero and two. We apply the filters mentioned above to detect peaks in the weak-lensing signal and compare them with the true population of dark matter halos present in the simulation. We confirm the stability and performance of a filter optimized for suppressing the contamination by large-scale structure. It allows the reliable detection of dark-matter halos with masses above a few times 1e13 M_sun/h with a fraction of spurious detections below ~10%. For sources at redshift two, 50% of the halos more massive than ~7e13 M_sun/h are detected, and completeness is reached at ~2e14 M_sun/h.Comment: 14 pages, 13 figures, accepted on A&

Effects of Shambhavi Mahamudra Kriya, a Multicomponent Breath-Based Yogic Practice ( Pranayama), on Perceived Stress and General Well-Being

Stress-induced disorders such as anxiety represent the leading causes of adult disability worldwide. Previous studies indicate that yoga and other contemplative practices such as pranayama, or controlled yogic breathing techniques, may be effective in the treatment of mood disorders and stress. In this study, 142 individuals (mean age = 43 years; SD = 13.90) participated in a 3-day retreat program during which they learned Shambhavi Mahamudra kriya, which is a yogic practice that includes both deep breathing and meditation techniques. Participants were instructed to practice the kriya each day for 21 minutes. After 6 weeks of daily practice, participants reported subjectively lower levels of perceived stress (Perceived Stress Scale) and higher levels of general well-being (General Well-Being Scale) compared to baseline. These results support the notion that Shambhavi Mahamudra kriya may represent a natural treatment for stress reduction

Evaluation of Abicipar Pegol (an Anti-VEGF DARPin Therapeutic) in Patients With Neovascular Age-Related Macular Degeneration: Studies in Japan and the United States

BACKGROUND AND OBJECTIVE: To evaluate comparability of abicipar pegol (abicipar) effects in patients with treatment-naïve neovascular age-related macular degeneration (nAMD) in Japan and the United States. PATIENTS AND METHODS: Phase 2, multicenter, randomized, double-masked, 20-week studies (BAMBOO, Japan; CYPRESS, United States). Patients (n = 25 each study) received three monthly intravitreal injections of abicipar 1 mg or 2 mg or five monthly intravitreal injections of ranibizumab 0.5 mg. RESULTS: Mean best-corrected visual acuity change from baseline at week 16 (primary endpoint) for abicipar 1 mg, abicipar 2 mg, and ranibizumab was +7.8 letters, +8.9 letters, and +17.4 letters (BAMBOO); +4.4 letters, +10.1 letters, and +15.2 letters (CYPRESS). Mean central retinal thickness change from baseline was −187.3 μm, −196.5 μm, and −230.4 μm (BAMBOO); −106.5 μm, −112.8 μm, and −124.4 μm (CYPRESS). Uveitis or vitritis was reported in three abicipar-treated patients. CONCLUSION: Abicipar demonstrated extended duration of effect and safety that were comparable between Japanese and non-Japanese patients with nAMD. Abicipar effectively treated Japanese patients with polypoidal choroidal vasculopathy