SATMC: Spectral Energy Distribution Analysis Through Markov Chains

We present the general purpose spectral energy distribution (SED) fitting tool SED Analysis Through Markov Chains (SATMC). Utilizing Monte Carlo Markov Chain (MCMC) algorithms, SATMC fits an observed SED to SED templates or models of the user's choice to infer intrinsic parameters, generate confidence levels and produce the posterior parameter distribution. Here we describe the key features of SATMC from the underlying MCMC engine to specific features for handling SED fitting. We detail several test cases of SATMC, comparing results obtained to traditional least-squares methods, which highlight its accuracy, robustness and wide range of possible applications. We also present a sample of submillimetre galaxies that have been fitted using the SED synthesis routine GRASIL as input. In general, these SMGs are shown to occupy a large volume of parameter space, particularly in regards to their star formation rates which range from ~30-3000 M_sun yr^-1 and stellar masses which range from ~10^10-10^12 M_sun. Taking advantage of the Bayesian formalism inherent to SATMC, we also show how the fitting results may change under different parametrizations (i.e., different initial mass functions) and through additional or improved photometry, the latter being crucial to the study of high-redshift galaxies.Comment: 17 pages, 11 figures, MNRAS accepte

A critical review of anti-adrenergic therapy in patients with heart failure and diabetes mellitus

Anti-adrenergic therapy has been widely accepted as an important therapeutic intervention in patients with chronic heart failure. However, there has been continuing controversy regarding the risks and clinical significance of metabolic effects of different anti-adrenergic drugs. This review summarizes what has been learned from clinical trial evidence regarding the benefits of anti-adrenergic drugs in diabetic patients with chronic heart failure

Agonist/Inosital Trisphosphate-Induced Release of Calcium from Murine Keratinocytes: A Possible Link with Keratinocyte Differentiation

Extracellular calcium concentrations markedly affect the pattern of proliferation and differentiation in cultured keratinocytes. When medium contains 0.1 mM calcium or above, the cells lose their proliferative ability, rapidly stratify, and terminally differentiate. Because 1,25(OH)2D3 (a modulator of Ca++ homeostasis) enhances the differentiation of keratinocytes, we investigated whether a link exists between 1 ,25(OH)2D3-induced release of inositol-1,4,5-trisphosphate (Ins(1,4,5)P3) from Ptdlns 4,5-P2 and intracellular calcium [Ca++]i release from keratinocytes. Specifically, primary culture of keratinocytes were loaded with fluorescence dye Fura-2AM (10 μM) and changes in fluorescence intensity were monitored at the excitation wavelengths of 340 and 380 nm and emission wavelength of 505 nm. Additions of two agonists, 1,25(OH)2D3 (1.2 × 10-9 M) and 13-Cis retinoic acid (0.2 × 10-9 M), to dye-loaded keratinocytes induced rapid release of [Ca++]i, respectively, followed by gradual return to the prestimulated state. Addition of Ins(1,4,5)P3 (10) to saponin-treated (leaky) keratinocytes also resulted in a rapid release of [Ca]. In contrast, the addition of inositrol-1,3,4,5-tetrakisphosphate. Ins(1,3,4,5)P at similar concentration exerted negligible effect. Taken together, these results support the view that 1,25(OH)2D3-induced [Ca++]i release in keratinocytes may be via the Ins(1,4,5)P3 induced early release of intracellular [Ca++]. This may explain, at least in part, 1,25(Oh)2D3-enhanced keratinocyte differentiatin

THEMIS Observations of the Magnetopause Electron Diffusion Region: Large Amplitude Waves and Heated Electrons

We present the first observations of large amplitude waves in a well-defined electron diffusion region at the sub-solar magnetopause using data from one THEMIS satellite. These waves identified as whistler mode waves, electrostatic solitary waves, lower hybrid waves and electrostatic electron cyclotron waves, are observed in the same 12-sec waveform capture and in association with signatures of active magnetic reconnection. The large amplitude waves in the electron diffusion region are coincident with abrupt increases in electron parallel temperature suggesting strong wave heating. The whistler mode waves which are at the electron scale and enable us to probe electron dynamics in the diffusion region were analyzed in detail. The energetic electrons (~30 keV) within the electron diffusion region have anisotropic distributions with T_{e\perp}/T_{e\parallel}>1 that may provide the free energy for the whistler mode waves. The energetic anisotropic electrons may be produced during the reconnection process. The whistler mode waves propagate away from the center of the 'X-line' along magnetic field lines, suggesting that the electron diffusion region is a possible source region of the whistler mode waves

Cardiotonic Modulation in Heart Failure Insights From Traditional Chinese Medicine∗

Medicinal herbs have been used over the past centuries for restoring the body's homeostatic balance. Contemporary use of herbal supplements remains widespread in many cultures as treatment for specific ailments. Many possess cardiovascular actions, and some interact with cardiac medications. However, there is variable scientific evidence with respect to their safety and efficacy, and few have been subjected to the same rigorous evaluation processes and regulations as contemporary pharmaceuticals (1). In the field of heart failure, we have also witnessed the failure of promising naturopathic therapies like hawthorn extract in translating their potential benefits in rigorous clinical trials (2,3)

Improved Tissue-Based Analytical Test Methods for Orellanine, a Biomarker of Cortinarius Mushroom Intoxication.

Orellanine (OR) toxin is produced by mushrooms of the genus Cortinarius which grow in North America and in Europe. OR poisoning is characterized by severe oliguric acute renal failure, with a mortality rate of 10%-30%. Diagnosis of OR poisoning currently hinges on a history of ingestion of Cortinarius mushrooms and histopathology of renal biopsies. A key step in the diagnostic approach is analysis of tissues for OR. Currently, tissue-based analytical methods for OR are nonspecific and lack sensitivity. The objectives of this study were: (1) to develop definitive HPLC and LC-MS/MS tissue-based analytical methods for OR; and (2) to investigate toxicological effects of OR in mice. The HPLC limit of quantitation was 10 µg/g. For fortification levels of 15 µg/g to 50 µg/g OR in kidney, the relative standard deviation was between 1.3% and 9.8%, and accuracy was within 1.5% to 7.1%. A matrix-matched calibration curve was reproduced in this range with a correlation coefficient (r) of 0.97-0.99. The limit of detection was 20 ng/g for LC-MS/MS. In OR-injected mice, kidney OR concentrations were 97 ± 51 µg/g on Day 0 and 17 ± 1 µg/g on termination Day 3. Splenic and liver injuries were novel findings in this mouse model. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology

Comparison of Rotational Energies and Rigidity of OCS-paraH_2 and OCS-4He complexes

We analyze the nature of the rotational energy level structure of the OCS-He and OCS-H_2 complexes with a comparison of exact calculations to several differentdynamical approximations. We compare with the clamped coordinate quasiadiabatic approximation that introduces an effective potential for each asymmetric rotor level, with an effective rotation Hamiltonian constructed from ground state averages of the inverse of the inertial matrix, and investigate the usefulness of the Eckart condition to decouple rotations and vibrations of these weakly bound complexes between linear OCS and 4He or H_2. Comparison with exact results allows an assessment of the accuracies of the different approximate methods and indicates which approaches are suitable for larger clusters of OCS with 4He and with H_2. We find the OCS-H_2 complex is considerably more rigid than the OCS-4He complex, suggesting that semi-rigid models are useful for analysis of larger clusters of H_2 with OCS.Comment: accepted by Chem. Phys., 200