The Deoxygenation and Hydrogenation Properties of Noble Metal-Based Bimetallic Phosphide Catalysts

With increasing concern regarding the environmental impacts of fossil fuels, and the difficulty of extracting petroleum feedstocks, alternative liquid fuels are becoming more desirable. Bio-oil, which is oil derived from biomass, is a renewable source of liquid fuels. However, the high oxygen and water content of bio-oil results in high corrosivity and low energy density, making it unusable in the current liquid fuel infrastructure. The process of removing heteroatom impurities from oil is known as hydrotreating. Current hydrotreating catalysts are optimized for refinement of petroleum, and are not suitable for bio-oil deoxygenation. Transition metal phosphides (such as Ru2P) are a class of materials that have garnered interest recently for their unique electronic, magnetic, and catalytic properties. Several metal-rich phosphide phases have also demonstrated promising hydrotreating activity and resistance to deactivation compared to noble metal catalysts. Some bimetallic phosphide phases have been shown to possess even greater activity than their monometallic counterparts due to synergistic effects between the constituent metals. A series of CoxRu2-xP (0 ≤ X ≤ 2) and CoxRh2-xP (0 ≤ X ≤ 2) catalysts supported on silica (SiO2) were prepared via impregnation followed by temperature programmed reduction (TPR). The furan and crotonaldehyde deoxygenation properties of the CoxRu2-xP/SiO2 catalysts were investigated and it was observed that the Co-rich catalysts possessed a higher activity than the Ru-rich catalysts with selectivity towards decarbonylation pathways and the production of C3 hydrocarbons. The CoxRu2-xP/SiO2 series showed no deactivation over 48 h in an 8 mol% furan/H2 feed at 578 K. The crotonaldehyde deoxygenation properties of the CoxRh2-xP/SiO2 were also investigated, and found to be more active than the CoxRu2-xP/SiO2 catalysts, with the Rh-rich catalysts possessing greater crotonaldehyde conversions than the Co-rich catalysts

Independent trapping and manipulation of microparticles using dexterous acoustic tweezers

An electronically controlled acoustic tweezer was used to demonstrate two acoustic manipulation phenomena: superposition of Bessel functions to allow independent manipulation of multiple particles and the use of higher-order Bessel functions to trap particles in larger regions than is possible with first-order traps. The acoustic tweezers consist of a circular 64-element ultrasonic array operating at 2.35MHz which generates ultrasonic pressure fields in a millimeter-scale fluid-filled chamber. The manipulation capabilities were demonstrated experimentally with 45 and 90-lm-diameter polystyrene spheres. These capabilities bring the dexterity of acoustic tweezers substantially closer to that of optical tweezers

Chronic Disease and Its Risk Factors Among Refugees and Asylees in Massachusetts, 2001-2005

INTRODUCTION. Better understanding of the health problems of refugees and people who are granted political asylum (asylees) in the United States may facilitate successful resettlement. We examined the prevalence of risk factors for and diagnoses of chronic disease among these groups in Massachusetts. METHODS. We retrospectively analyzed health screening data from 4,239 adult refugees and asylees who arrived in Massachusetts from January 1, 2001, through December 31, 2005. We determined prevalence of obesity/overweight, hypertension, coronary artery disease (CAD), diabetes, and anemia. Analyses included multivariate logistic regression to determine associations between CAD and diabetes with region of origin. RESULTS. Almost half of our sample (46.8%) was obese/overweight, and 22.6% had hypertension. CAD, diabetes, and anemia were documented in 3.7%, 3.1%, and 12.8%, respectively. People from the Europe and Central Asia region were more likely than those from other regions to have CAD (odds ratio, 5.55; 95% confidence interval, 2.95-10.47). CONCLUSIONS. The prevalence of obesity/overweight and hypertension was high among refugees and asylees, but the prevalence of documented CAD and diabetes was low. We noted significant regional variations in prevalence of risk factors and chronic diseases. Future populations resettling in the United States should be linked to more resources to address their long-term health care needs and to receive culturally appropriate counseling on risk reduction.Massachusetts Department of Public Health; the General Internal Medicine Fellowship; Boston University School of Medicin

Pelvic Positioning in the Supine Position Leads to More Consistent Cup Orientation after Total Hip Arthroplasty

Aims: This study aims to 1) Determine the difference in pelvic position that occurs between surgery and radiographic, supine, post-operative assessment; 2) Examine how the difference in pelvic position influences subsequent cup orientation and 3) Establish whether pelvic position, and thereafter cup orientation differences exist between THAs performed in the supine versus the lateral decubitus positions. Materials and Methods: 321 THAs who had intra-operative, post-cup impaction, AP pelvic radiograph, in the operative position were studied; 167 were performed with patient supine (anterior approach), whilst 154 were performed in lateral decubitus (posterior approach). Cup inclination/anteversion was measured from intra- and post-operative radiographs and difference (Δ) was determined. The target zone was inclination/anteversion of 40/20°±10°. Change in pelvic position (tilt, rotation, obliquity) between surgery and post-operatively was calculated from Δinclination/anteversion using the Levenberg-Marquardt algorithm. Results: The post-operative inclination/anteversion was 40°±8/23°±9. 74 had Δinclination and/or Δanteversion>±10° (21%). Intra-operatively (compared to post-operative), the pelvis was on average 4°±10 anteriorly tilted; 1°±10 internally rotated and 1°±5 adducted. Having Δinclination and/or Δanteversion >±10° was associated with a 3.5 odds ratio of having a cup outside the target. A greater proportion of hips operated in the lateral decubitus had Δinclination and/or Δanteversion >±10° (54/153), compared to supine (8/167) (p<0.001). A greater number of cups achieved the target orientation in supine (120/167;73%), compared to lateral position (67/153;44%) (p<0.001). Intra-operatively, pelvis was more anteriorly tilted (p<0.001) and hemi-pelvis was more internally rotated (p=0.04) in lateral position. Conclusion: Pelvic movement is significantly less in supine position, which leads to more consistent cup orientation. Significant differences in pelvic tilt and rotation were seen in the lateral position. Clinical Relevance: Understanding the differences in pelvic orientation and cup orientation between supine and lateral decubitus positions may facilitate better intraoperative practices for surgeons

Evidence for a Long-period Planet Orbiting Epsilon Eridani

High precision radial velocity (RV) measurements spanning the years 1980.8--2000.0 are presented for the nearby (3.22 pc) K2 V star $\epsilon$ Eri. These data, which represent a combination of six independent data sets taken with four different telescopes, show convincing variations with a period of $\approx$ 7 yrs. A least squares orbital solution using robust estimation yields orbital parameters of period, $P$ = 6.9 yrs, velocity $K$-amplitude $=$ 19 {\ms}, eccentricity $e$ $=$ 0.6, projected companion mass $M$ sin $i$ = 0.86 $M_{Jupiter}$, and semi-major axis $a_2$ $=$ 3.3 AU. Ca II H&K S-index measurements spanning the same time interval show significant variations with periods of 3 and 20 yrs, yet none at the RV period. If magnetic activity were responsible for the RV variations then it produces a significantly different period than is seen in the Ca II data. Given the lack of Ca II variation with the same period as that found in the RV measurements, the long-lived and coherent nature of these variations, and the high eccentricity of the implied orbit, Keplerian motion due to a planetary companion seems to be the most likely explanation for the observed RV variations. The wide angular separation of the planet from the star (approximately 1 arc-second) and the long orbital period make this planet a prime candidate for both direct imaging and space-based astrometric measurements.Comment: To appear in Astrophysical Journal Letters. 9 pages, 2 figure

Transit Timing Observations from Kepler: VII. Confirmation of 27 planets in 13 multiplanet systems via Transit Timing Variations and orbital stability

We confirm 27 planets in 13 planetary systems by showing the existence of statistically significant anti-correlated transit timing variations (TTVs), which demonstrates that the planet candidates are in the same system, and long-term dynamical stability, which places limits on the masses of the candidates---showing that they are planetary. %This overall method of planet confirmation was first applied to \kepler systems 23 through 32. All of these newly confirmed planetary systems have orbital periods that place them near first-order mean motion resonances (MMRs), including 6 systems near the 2:1 MMR, 5 near 3:2, and one each near 4:3, 5:4, and 6:5. In addition, several unconfirmed planet candidates exist in some systems (that cannot be confirmed with this method at this time). A few of these candidates would also be near first order MMRs with either the confirmed planets or with other candidates. One system of particular interest, Kepler-56 (KOI-1241), is a pair of planets orbiting a 12th magnitude, giant star with radius over three times that of the Sun and effective temperature of 4900 K---among the largest stars known to host a transiting exoplanetary system.Comment: 12 pages, 13 figures, 5 tables. Submitted to MNRA

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE) : study protocol for a randomized controlled trial

Peer reviewedPublisher PD

Inference with interference between units in an fMRI experiment of motor inhibition

An experimental unit is an opportunity to randomly apply or withhold a treatment. There is interference between units if the application of the treatment to one unit may also affect other units. In cognitive neuroscience, a common form of experiment presents a sequence of stimuli or requests for cognitive activity at random to each experimental subject and measures biological aspects of brain activity that follow these requests. Each subject is then many experimental units, and interference between units within an experimental subject is likely, in part because the stimuli follow one another quickly and in part because human subjects learn or become experienced or primed or bored as the experiment proceeds. We use a recent fMRI experiment concerned with the inhibition of motor activity to illustrate and further develop recently proposed methodology for inference in the presence of interference. A simulation evaluates the power of competing procedures.Comment: Published by Journal of the American Statistical Association at http://www.tandfonline.com/doi/full/10.1080/01621459.2012.655954 . R package cin (Causal Inference for Neuroscience) implementing the proposed method is freely available on CRAN at https://CRAN.R-project.org/package=ci

The Calcitonin and Glucocorticoids Combination: Mechanistic Insights into Their Class-Effect Synergy in Experimental Arthritis

PMCID: PMC3564948This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited