Retired A Stars and Their Companions VI. A Pair of Interacting Exoplanet Pairs Around the Subgiants 24 Sextanis and HD200964

We report radial velocity measurements of the G-type subgiants 24 Sextanis (=HD90043) and HD200964. Both are massive, evolved stars that exhibit periodic variations due to the presence of a pair of Jovian planets. Photometric monitoring with the T12 0.80m APT at Fairborn Observatory demonstrates both stars to be constant in brightness to <= 0.002 mag, thus strengthening the planetary interpretation of the radial velocity variations. 24 Sex b,c have orbital periods of 453.8 days and 883~days, corresponding to semimajor axes 1.333 AU and 2.08 AU, and minimum masses (Msini) 1.99 Mjup and 0.86 Mjup, assuming a stellar mass 1.54 Msun. HD200964 b,c have orbital periods of 613.8 days and 825 days, corresponding to semimajor axes 1.601 AU and 1.95 AU, and minimum masses 1.85 Mjup and 0.90 Mjup, assuming M* = 1.44 Msun. We also carry out dynamical simulations to properly account for gravitational interactions between the planets. Most, if not all, of the dynamically stable solutions include crossing orbits, suggesting that each system is locked in a mean motion resonance that prevents close encounters and provides long-term stability. The planets in the 24 Sex system likely have a period ratio near 2:1, while the HD200964 system is even more tightly packed with a period ratio close to 4:3. However, we caution that further radial velocity observations and more detailed dynamical modelling will be required to provide definitive and unique orbital solutions for both cases, and to determine whether the two systems are truly resonant.Comment: AJ accepte

Composition of dissolved organic matter within a lacustrine environment

Freshwater dissolved organic matter (DOM) is a complex mixture of chemical components that are central to many environmental processes, including carbon and nitrogen cycling. However, questions remain as to its chemical characteristics, sources and transformation mechanisms. Here, we employ 1- and 2-D nuclear magnetic resonance (NMR) spectroscopy to investigate the structural components of lacustrine DOM from Ireland, and how it varies within a lake system, as well as to assess potential sources. Major components found, such as carboxyl-rich alicyclic molecules (CRAM) are consistent with those recently identified in marine and freshwater DOM. Lignin-type markers and protein/peptides were identified and vary spatially. Phenylalanine was detected in lake areas influenced by agriculture, whereas it is not detectable where zebra mussels are prominent. The presence of peptidoglycan, lipoproteins, large polymeric carbo- hydrates and proteinaceous material supports the substantial contribution of material derived from microorganisms. Evidence is provided that peptidoglycan and silicate species may in part originate from soil microbes

A multi-targeted approach to suppress tumor-promoting inflammation

Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-κB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes

Safety & efficacy of lifileucel (LN-144) tumor infiltrating lymphocyte therapy in metastatic melanoma patients after progression on multiple therapies – independent review committee data update

Treatment options are limited for patients with advanced melanoma who have progressed on checkpoint inhibitors and targeted therapies such as BRAF/MEK inhibitors (if BRAF-V600E mutated). Adoptive cell therapy utilizing tumor-infiltrating lymphocytes (TIL) has shown antitumor efficacy with durable responses in heavily pretreated melanoma patients. Safety and efficacy of lifileucel, a centrally manufactured cryopreserved autologous TIL therapy assessed by both investigator and an independent review committee (IRC), are presented

Theoretical Criteria for Scattering Dark States in Nanostructured Particles

Nanostructures with multiple resonances can exhibit a suppressed or even completely eliminated scattering of light, called a scattering dark state. We describe this phenomenon with a general treatment of light scattering from a multiresonant nanostructure that is spherical or nonspherical but subwavelength in size. With multiple resonances in the same channel (i.e., same angular momentum and polarization), coherent interference always leads to scattering dark states in the low-absorption limit, regardless of the system details. The coupling between resonances is inevitable and can be interpreted as arising from far-field or near-field. This is a realization of coupled-resonator-induced transparency in the context of light scattering, which is related to but different from Fano resonances. Explicit examples are given to illustrate these concepts.Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies (Contract W911NF-13-D-0001)National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Grant DMR-0819762

Endovascular Thrombectomy for Ischemic Stroke Increases Disability-Free Survival, Quality of Life, and Life Expectancy and Reduces Cost

Background: Endovascular thrombectomy improves functional outcome in large vessel occlusion ischemic stroke. We examined disability, quality of life, survival and acute care costs in the EXTEND-IA trial, which used CT-perfusion imaging selection. Methods: Large vessel ischemic stroke patients with favorable CT-perfusion were randomized to endovascular thrombectomy after alteplase versus alteplase-only. Clinical outcome was prospectively measured using 90-day modified Rankin scale (mRS). Individual patient expected survival and net difference in Disability/Quality-adjusted life years (DALY/QALY) up to 15 years from stroke were modeled using age, sex, 90-day mRS, and utility scores. Level of care within the first 90 days was prospectively measured and used to estimate procedure and inpatient care costs (US$reference year 2014). Results: There were 70 patients, 35 in each arm, mean age 69, median NIHSS 15 (IQR 12-19). The median (IQR) disability-weighted utility score at 90 days was 0.65 (0.00-0.91) in the alteplase-only versus 0.91 (0.65-1.00) in the endovascular group (p = 0.005). Modeled life expectancy was greater in the endovascular versus alteplaseonly group (median 15.6 versus 11.2 years, p = 0.02). The endovascular thrombectomy group had fewer simulated DALYs lost over 15 years [median (IQR) 5.5 (3.2-8.7) versus 8.9 (4.7-13.8), p = 0.02] and more QALY gained [median (IQR) 9.3 (4.2-13.1) versus 4.9 (0.3-8.5), p = 0.03]. Endovascular patients spent less time in hospital [median (IQR) 5 (3-11) days versus 8 (5-14) days, p = 0.04] and rehabilitation [median (IQR) 0 (0-28) versus 27 (0-65) days, p = 0.03]. The estimated inpatient costs in the first 90 days were less in the thrombectomy group (average US$15,689 versus US$30,569, p = 0.008) offsetting the costs of interhospital transport and the thrombectomy procedure (average US$10,515). The average saving per patient treated with thrombectomy was US$4,365. c Conclusion: Thrombectomy patients with large vessel occlusion and salvageable tissue on CT-perfusion had reduced length of stay and overall costs to 90 days. There was evidence of clinically relevant improvement in long-term survival and quality of life.Peer reviewe

Absolute quantitative total-body small-animal SPECT with focusing pinholes

Purpose: In pinhole SPECT, attenuation of the photon flux on trajectories between source and pinholes affects quantitative accuracy of reconstructed images. Previously we introduced iterative methods that compensate for image degrading effects of detector and pinhole blurring, pinhole sensitivity and scatter for multi-pinhole SPECT. The aim of this paper is (1) to investigate the accuracy of the Chang algorithm in rodents and (2) to present a practical Changbased method using body outline contours obtained with optical cameras. Methods: Here we develop and experimentally validate a practical method for attenuation correction based on a Chang first-order method. This approach has the advantage that it is employed after, and therefore independently from, iterative reconstruction. Therefore, no new system matrix has to be calculated for each specific animal. Experiments with phantoms and animals were performed with a highresolution focusing multi-pinhole SPECT system (USPECT-II, MILabs, The Netherlands). This SPECT system provides three additional optical camera images of the animal for each SPECT scan from which the animal contour can be estimated. Results: Phantom experiments demonstrated that an average quantification error of –18.7% was reduced to –1.7% when both window-based scatter correction and Chang correction based on the body outline from optical images were applied. Without scatter and attenuation correction, quantification errors in a sacrificed rat containing sources with known activity ranged from –23.6 to –9.3%. These errors were reduced to values between –6.3 and +4.3% (with an average magnitude of 2.1%) after applying scatter and Chang attenuation correction. Conclusion: We conclude that the modified Chang correction based on body contour combined with window-based scatter correction is a practical method for obtaining small-animal SPECT images with high quantitative accuracy.Radiation, Radionuclides and ReactorsApplied Science

The X-ray properties of million solar mass black holes

We present new Chandra X-ray observations of seven low-mass black holes (~1e6 Msun) accreting at low Eddington ratios between -2.0<log L/Ledd<-1.5. We compare the X-ray properties of these seven low-mass active galactic nuclei (AGN) to a total of 73 other low-mass AGN in the literature with published Chandra observations (with Eddington ratios extending from -2.0<log L/Ledd<-0.1). We do not find any statistical differences between low- and high-Eddington ratio low-mass AGN in the distributions of their X-ray to ultraviolet luminosity ratios (aox), or in their X-ray spectral shapes. Furthermore, the aox distribution of low-L/Ledd AGN displays an X-ray weak tail that is also observed within high-L/Ledd objects. Our results indicate that between -2<log L/Ledd<-0.1, there is no systematic change in the structure of the accretion flow for active galaxies hosting 1e6 Msun black holes. We examine the accuracy of current bolometric luminosity estimates for our low-L/Ledd objects with new Chandra observations, and it is plausible that their Eddington ratios could be underestimated by up to an order of magnitude. If so, then in analogy with weak emission line quasars, we suggest that accretion from a geometrically thick, radiatively inefficient `slim disk' could explain their diverse properties in aox. Alternatively, if current Eddington ratios are in fact correct (or overestimated), then the X-ray weak tail would imply that there is diversity in disk/corona couplings among individual low-mass objects. Finally, we conclude by noting that the aox distribution for low-mass black holes may have favorable consequences for the epoch of cosmic reionization being driven by AGN.Comment: 14 pages, 6 figures, 6 tables. Accepted for publication in Ap