Showing papers by "Drexel University published in 2013"

The Genotype-Tissue Expression (GTEx) project

Abstract: Genome-wide association studies have identified thousands of loci for common diseases, but, for the majority of these, the mechanisms underlying disease susceptibility remain unknown. Most associated variants are not correlated with protein-coding changes, suggesting that polymorphisms in regulatory regions probably contribute to many disease phenotypes. Here we describe the Genotype-Tissue Expression (GTEx) project, which will establish a resource database and associated tissue bank for the scientific community to study the relationship between genetic variation and gene expression in human tissues.

Cation Intercalation and High Volumetric Capacitance of Two-Dimensional Titanium Carbide

Abstract: The intercalation of ions into layered compounds has long been exploited in energy storage devices such as batteries and electrochemical capacitors However, few host materials are known for ions much larger than lithium We demonstrate the spontaneous intercalation of cations from aqueous salt solutions between two-dimensional (2D) Ti3C2 MXene layers MXenes combine 2D conductive carbide layers with a hydrophilic, primarily hydroxyl-terminated surface A variety of cations, including Na+, K+, NH4+, Mg2+, and Al3+, can also be intercalated electrochemically, offering capacitance in excess of 300 farads per cubic centimeter (much higher than that of porous carbons) This study provides a basis for exploring a large family of 2D carbides and carbonitrides in electrochemical energy storage applications using single- and multivalent ions

The State of US Health, 1990-2010: Burden of Diseases, Injuries, and Risk Factors

Abstract: Importance Understanding the major health problems in the United States and how they are changing over time is critical for informing national health policy. Objectives To measure the burden of diseases, injuries, and leading risk factors in the United States from 1990 to 2010 and to compare these measurements with those of the 34 countries in the Organisation for Economic Co-operation and Development (OECD) countries. Design We used the systematic analysis of descriptive epidemiology of 291 diseases and injuries, 1160 sequelae of these diseases and injuries, and 67 risk factors or clusters of risk factors from 1990 to 2010 for 187 countries developed for the Global Burden of Disease 2010 Study to describe the health status of the United States and to compare US health outcomes with those of 34 OECD countries. Years of life lost due to premature mortality (YLLs) were computed by multiplying the number of deaths at each age by a reference life expectancy at that age. Years lived with disability (YLDs) were calculated by multiplying prevalence (based on systematic reviews) by the disability weight (based on population-based surveys) for each sequela; disability in this study refers to any short- or long-term loss of health. Disability-adjusted life-years (DALYs) were estimated as the sum of YLDs and YLLs. Deaths and DALYs related to risk factors were based on systematic reviews and meta-analyses of exposure data and relative risks for risk-outcome pairs. Healthy life expectancy (HALE) was used to summarize overall population health, accounting for both length of life and levels of ill health experienced at different ages. Results US life expectancy for both sexes combined increased from 75.2 years in 1990 to 78.2 years in 2010; during the same period, HALE increased from 65.8 years to 68.1 years. The diseases and injuries with the largest number of YLLs in 2010 were ischemic heart disease, lung cancer, stroke, chronic obstructive pulmonary disease, and road injury. Age-standardized YLL rates increased for Alzheimer disease, drug use disorders, chronic kidney disease, kidney cancer, and falls. The diseases with the largest number of YLDs in 2010 were low back pain, major depressive disorder, other musculoskeletal disorders, neck pain, and anxiety disorders. As the US population has aged, YLDs have comprised a larger share of DALYs than have YLLs. The leading risk factors related to DALYs were dietary risks, tobacco smoking, high body mass index, high blood pressure, high fasting plasma glucose, physical inactivity, and alcohol use. Among 34 OECD countries between 1990 and 2010, the US rank for the age-standardized death rate changed from 18th to 27th, for the age-standardized YLL rate from 23rd to 28th, for the age-standardized YLD rate from 5th to 6th, for life expectancy at birth from 20th to 27th, and for HALE from 14th to 26th. Conclusions and Relevance From 1990 to 2010, the United States made substantial progress in improving health. Life expectancy at birth and HALE increased, all-cause death rates at all ages decreased, and age-specific rates of years lived with disability remained stable. However, morbidity and chronic disability now account for nearly half of the US health burden, and improvements in population health in the United States have not kept pace with advances in population health in other wealthy nations.

The baryon oscillation spectroscopic survey of sdss-iii

Abstract: The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg2 to measure BAO to redshifts z < 0.7. Observations of neutral hydrogen in the Lyα forest in more than 150,000 quasar spectra (g < 22) will constrain BAO over the redshift range 2.15 < z < 3.5. Early results from BOSS include the first detection of the large-scale three-dimensional clustering of the Lyα forest and a strong detection from the Data Release 9 data set of the BAO in the clustering of massive galaxies at an effective redshift z = 0.57. We project that BOSS will yield measurements of the angular diameter distance dA to an accuracy of 1.0% at redshifts z = 0.3 and z = 0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Lyα forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate DA (z) and H –1(z) parameters to an accuracy of 1.9% at z ~ 2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS.

Intercalation and delamination of layered carbides and carbonitrides

Abstract: Intercalation and delamination of two-dimensional solids in many cases is a requisite step for exploiting their unique properties. Herein we report on the intercalation of two-dimensional Ti3C2, Ti3CN and TiNbC-so called MXenes. Intercalation of hydrazine, and its co-intercalation with N,N-dimethylformamide, resulted in increases of the c-lattice parameters of surface functionalized f-Ti3C2, from 19.5 to 25.48 and 26.8 A, respectively. Urea is also intercalated into f-Ti3C2. Molecular dynamics simulations suggest that a hydrazine monolayer intercalates between f-Ti3C2 layers. Hydrazine is also intercalated into f-Ti3CN and f-TiNbC. When dimethyl sulphoxide is intercalated into f-Ti3C2, followed by sonication in water, the f-Ti3C2 is delaminated forming a stable colloidal solution that is in turn filtered to produce MXene 'paper'. The latter shows excellent Li-ion capacity at extremely high charging rates.

New Two-Dimensional Niobium and Vanadium Carbides as Promising Materials for Li-Ion Batteries

Abstract: New two-dimensional niobium and vanadium carbides have been synthesized by selective etching, at room temperature, of Al from Nb2AlC and V2AlC, respectively. These new matrials are promising electrode materials for Li-ion batteries, demonstrating good capability to handle high charge–discharge rates. Reversible capacities of 170 and 260 mA·h·g–1 at 1 C, and 110 and 125 mA·h·g–1 at 10 C were obtained for Nb2C and V2C-based electrodes, respectively.

Capacitive Energy Storage in Nanostructured Carbon–Electrolyte Systems

Abstract: Securing our energy future is the most important problem that humanity faces in this century. Burning fossil fuels is not sustainable, and wide use of renewable energy sources will require a drastically increased ability to store electrical energy. In the move toward an electrical economy, chemical (batteries) and capacitive energy storage (electrochemical capacitors or supercapacitors) devices are expected to play an important role. This Account summarizes research in the field of electrochemical capacitors conducted over the past decade.Overall, the combination of the right electrode materials with a proper electrolyte can successfully increase both the energy stored by the device and its power, but no perfect active material exists and no electrolyte suits every material and every performance goal. However, today, many materials are available, including porous activated, carbide-derived, and templated carbons with high surface areas and porosities that range from subnanometer to just a few nanometers. ...

Ultralight and Highly Compressible Graphene Aerogels

Abstract: Chemically converted graphene aerogels with ultralight density and high compressibility are prepared by diamine-mediated functionalization and assembly, followed by microwave irradiation. The resulting graphene aerogels with density as low as 3 mg cm(-3) show excellent resilience and can completely recover after more than 90% compression. The ultralight graphene aerogels possessing high elasticity are promising as compliant and energy-absorbing materials.

Perovskite oxides for visible-light-absorbing ferroelectric and photovoltaic materials

Abstract: Most known ferroelectric photovoltaic materials have very wide electronic bandgaps (that is, they absorb only high-energy photons) but here a family of perovskite oxides is described that have tunable bandgaps, allowing their use across the whole visible-light spectrum. The spontaneous electrical polarization that characterizes a ferroelectric material is attractive for solar-cell applications as the positive and negative charges generated by light absorption have a natural tendency to separate, making them easier to harvest efficiently. Unfortunately most known ferroelectrics have wide electronic bandgaps — that is they absorb only higher energy photons that make up a small fraction of the solar spectrum. Ilya Grinberg and colleagues now show that a classic ferroelectric can be chemically engineered to tune the bandgap over a broad range, achieving strong absorption and photocurrent generation across the solar spectrum. Ferroelectrics have recently attracted attention as a candidate class of materials for use in photovoltaic devices, and for the coupling of light absorption with other functional properties1,2,3,4,5,6,7. In these materials, the strong inversion symmetry breaking that is due to spontaneous electric polarization promotes the desirable separation of photo-excited carriers and allows voltages higher than the bandgap, which may enable efficiencies beyond the maximum possible in a conventional p–n junction solar cell2,6,8,9,10. Ferroelectric oxides are also stable in a wide range of mechanical, chemical and thermal conditions and can be fabricated using low-cost methods such as sol–gel thin-film deposition and sputtering3,5. Recent work3,5,11 has shown how a decrease in ferroelectric layer thickness and judicious engineering of domain structures and ferroelectric–electrode interfaces can greatly increase the current harvested from ferroelectric absorber materials, increasing the power conversion efficiency from about 10−4 to about 0.5 per cent. Further improvements in photovoltaic efficiency have been inhibited by the wide bandgaps (2.7–4 electronvolts) of ferroelectric oxides, which allow the use of only 8–20 per cent of the solar spectrum. Here we describe a family of single-phase solid oxide solutions made from low-cost and non-toxic elements using conventional solid-state methods: [KNbO3]1 − x[BaNi1/2Nb1/2O3 − δ]x (KBNNO). These oxides exhibit both ferroelectricity and a wide variation of direct bandgaps in the range 1.1–3.8 electronvolts. In particular, the x = 0.1 composition is polar at room temperature, has a direct bandgap of 1.39 electronvolts and has a photocurrent density approximately 50 times larger than that of the classic ferroelectric (Pb,La)(Zr,Ti)O3 material. The ability of KBNNO to absorb three to six times more solar energy than the current ferroelectric materials suggests a route to viable ferroelectric semiconductor-based cells for solar energy conversion and other applications.

Co-opted Boards

Abstract: We argue that not all independent directors are equally effective in monitoring top management. Specifically, directors who are appointed by the CEO are likely to have stronger allegiance to the CEO and will be weaker monitors. To examine this hypothesis, we propose and empirically deploy two new measures of board composition. Co-option is the fraction of the board comprised of directors appointed after the sitting CEO assumed office. Consistent with Co-option serving to measure board capture, as Co-option increases board monitoring intensity decreases: turnover-performance sensitivity diminishes; pay level increases but without a commensurate increase in pay-performance sensitivity; and investment in hard assets increases. Further analysis suggests that even independent directors who are co-opted are less effective monitors. Non-Co-opted Independence –– the fraction of the board comprised of independent directors who were already on the board before the CEO assumed office –– has more explanatory power for monitoring effectiveness than the traditional measure of board independence.

Designing a deep-ultraviolet nonlinear optical material with a large second harmonic generation response.

Abstract: The generation of intense coherent deep-UV light from nonlinear optical materials is crucial to applications ranging from semiconductor photolithography and laser micromachining to photochemical synthesis. However, few materials with large second harmonic generation (SHG) and a short UV-cutoff edge are effective down to 200 nm. A notable exception is KBe2BO3F2, which is obtained from a solid-state reaction of highly toxic beryllium oxide powders. We designed and synthesized a benign polar material, Ba4B11O20F, that satisfies these requirements and exhibits the largest SHG response in known borates containing neither lone-pair-active anions nor second-order Jahn-Teller-active transition metals. We developed a microscopic model to explain the enhancement, which is unexpected on the basis of conventional anionic group theory arguments. Crystal engineering of atomic displacements along the polar axis, which are difficult to attribute to or identify within unique anionic moieties, and greater cation polarizabilities are critical to the design of next-generation SHG materials.

Knitted and screen printed carbon-fiber supercapacitors for applications in wearable electronics

Abstract: The field of energy textiles is growing but continues to face two main challenges: (1) flexible energy storage does not yet exist in a form that is directly comparable with everyday fabrics including their feel, drape and thickness, and (2) in order to produce an “energy textile” as part of a garment, it must be fabricated in a systematic manner allowing for multiple components of e-textiles to be integrated simultaneously. To help address these issues, we have developed textile supercapacitors based on knitted carbon fibers and activated carbon ink. We show capacitances as high as 0.51 F cm−2 per device at 10 mV s−1, which is directly comparable with those of standard activated carbon film electrodes tested under the same conditions. We also demonstrate the performance of the device when bent at 90°, 135°, 180° and when stretched. This is the first report on knitting as a fabrication technique for integrated energy storage devices.

In-Hospital Complications Associated With Catheter Ablation of Atrial Fibrillation in the United States Between 2000 and 2010 Analysis of 93 801 Procedures

Abstract: Background—Atrial fibrillation ablation has made tremendous progress with respect to innovation, efficacy, and safety. However, limited data exist regarding the burden and trends in adverse outcomes arising from this procedure. The aim of our study was to examine the frequency of adverse events attributable to atrial fibrillation (AF) ablation and the influence of operator and hospital volume on outcomes. Methods and Results—With the use of the Nationwide Inpatient Sample, we identified AF patients treated with catheter ablation. We investigated common complications including cardiac perforation and tamponade, pneumothorax, stroke, transient ischemic attack, vascular access complications (hemorrhage/hematoma, vascular complications requiring surgical repair, and accidental arterial puncture), and in-hospital death described with AF ablation, and we defined these complications by using validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. An estimated 93...

Direct recordings of grid-like neuronal activity in human spatial navigation

Abstract: Grid cells in the entorhinal cortex appear to represent spatial location via a triangular coordinate system. Such cells, which have been identified in rats, bats and monkeys, are believed to support a wide range of spatial behaviors. Recording neuronal activity from neurosurgical patients performing a virtual-navigation task, we identified cells exhibiting grid-like spiking patterns in the human brain, suggesting that humans and simpler animals rely on homologous spatial-coding schemes.

A Survey of Real-Time Strategy Game AI Research and Competition in StarCraft

Abstract: This paper presents an overview of the existing work on AI for real-time strategy (RTS) games. Specifically, we focus on the work around the game StarCraft, which has emerged in the past few years as the unified test bed for this research. We describe the specific AI challenges posed by RTS games, and overview the solutions that have been explored to address them. Additionally, we also present a summary of the results of the recent StarCraft AI competitions, describing the architectures used by the participants. Finally, we conclude with a discussion emphasizing which problems in the context of RTS game AI have been solved, and which remain open.

Corporate Social Responsibility, Customer Orientation, and the Job Performance of Frontline Employees

Abstract: A study involving a Global 500 company finds that frontline employees’ perceptions of corporate social responsibility (CSR) can contribute to their customer orientation (self-rated) and objective job performance (supervisor-rated) by activating social identification processes. Employees identify with the organization based in part on the extent to which CSR is supported by salient and job-relevant others both internal and external to the organization. Looking internally, employees identify with the organization to the extent that they perceive management to support CSR. Looking externally, employees can identify with customers (called employee-customer identification) to the extent they perceive customers to support the company’s CSR. Both effects are enhanced when employees feel CSR is an important (versus non-important) part of their self-concept. Organizational identification directly drives job performance while employee-customer identification contributes to job performance through its effects on organizational identification and customer orientation.

Injectable Nano-Network for Glucose-Mediated Insulin Delivery

Abstract: Diabetes mellitus, a disorder of glucose regulation, is a global burden affecting 366 million people across the world. An artificial “closed-loop” system able to mimic pancreas activity and release insulin in response to glucose level changes has the potential to improve patient compliance and health. Herein we develop a glucose-mediated release strategy for the self-regulated delivery of insulin using an injectable and acid-degradable polymeric network. Formed by electrostatic interaction between oppositely charged dextran nanoparticles loaded with insulin and glucose-specific enzymes, the nanocomposite-based porous architecture can be dissociated and subsequently release insulin in a hyperglycemic state through the catalytic conversion of glucose into gluconic acid. In vitro insulin release can be modulated in a pulsatile profile in response to glucose concentrations. In vivo studies validated that these formulations provided improved glucose control in type 1 diabetic mice subcutaneously administered w...

“Once You’ve Blended the Cake, You Can’t Take the Parts Back to the Main Ingredients”: Black Gay and Bisexual Men’s Descriptions and Experiences of Intersectionality

Abstract: Although Black gay and bisexual men have written eloquently about the intersections of race, gender, and sexual identity in anthologies such as Brother to Brother and In the Life, empirical studies of intersectionality with men, and Black gay and bisexual men in particular are rare. This qualitative study examined descriptions and experiences of intersectionality in individual interviews with 12 U.S. Black self-identified gay (n = 9) and bisexual (n =3) men in Washington, DC. Participants ranged in age from 21 and 44 (M = 36.33) and were predominantly highly educated and middle income. Research questions were: (1) How do participants describe and experience intersections of race, gender, and sexual identity?; (2) How do social processes shape their social identities?; (3) What are their challenges due to intersections of race, gender, and sexual identity?; and (4) What are the perceived benefits of these intersections? Analyses highlighted four key themes: (1) explicit and implicit descriptions of intersectionality; (2) the primacy of identities as Black and/or Black men first; (3) challenges such as negative stereotypes, racial microaggressions in mainstream and White LGB communities, heterosexism in Black communities, and gender role pressures to act “masculine”; and (4) perceived benefits such as psychological growth, liberation from traditional gender role or heteronormative expectations, and the freedom that being outsiders or “never being comfortable” confers in terms of exploring new opportunities and experiences. These findings imply that intersectionality can be expanded to incorporate the strengths/assets of intersectional identities in addition to oppression based on interlocking social identities.

Indoor aerosols: from personal exposure to risk assessment

Abstract: Motivated by growing considerations of the scale, severity, and risks associated with human exposure to indoor particulate matter, this work reviewed existing literature to: (i) identify state-of-the-art experimental techniques used for personal exposure assessment; (ii) compare exposure levels reported for domestic/school settings in different countries (excluding exposure to environmental tobacco smoke and particulate matter from biomass cooking in developing countries); (iii) assess the contribution of outdoor background vs indoor sources to personal exposure; and (iv) examine scientific understanding of the risks posed by personal exposure to indoor aerosols. Limited studies assessing integrated daily residential exposure to just one particle size fraction, ultrafine particles, show that the contribution of indoor sources ranged from 19% to 76%. This indicates a strong dependence on resident activities, source events and site specificity, and highlights the importance of indoor sources for total personal exposure. Further, it was assessed that 10-30% of the total burden of disease from particulate matter exposure was due to indoor-generated particles, signifying that indoor environments are likely to be a dominant environmental factor affecting human health. However, due to challenges associated with conducting epidemiological assessments, the role of indoor-generated particles has not been fully acknowledged, and improved exposure/risk assessment methods are still needed, together with a serious focus on exposure control.

Music for stress and anxiety reduction in coronary heart disease patients

Abstract: Background Individuals with coronary heart disease (CHD) often suffer from severe distress due to diagnosis, hospitalization, surgical procedures, uncertainty of outcome, fear of dying, doubts about progress in recovery, helplessness and loss of control. Such adverse effects put the cardiac patient at greater risk for complications, including sudden cardiac death. It is therefore of crucial importance that the care of people with CHD focuses on psychological as well as physiological needs. Music interventions have been used to reduce anxiety and distress and improve physiological functioning in medical patients; however its efficacy for people with CHD needs to be evaluated. Objectives To update the previously published review that examined the effects of music interventions with standard care versus standard care alone on psychological and physiological responses in persons with CHD. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (2012, Issue 10), MEDLINE (OvidSP, 1950 to October week 4 2012), EMBASE (OvidSP, 1974 to October week 5 2012), CINAHL (EBSCOhost, 1982 to 9 November 2012), PsycINFO (OvidSP, 1806 to October week 5 2012), LILACS (Virtual Health Library, 1982 to 15 November 2012), Social Science Citation Index (ISI, 1974 to 9 November 2012), a number of other databases, and clinical trial registers. We also conducted handsearching of journals and reference lists. We applied no language restrictions. Selection criteria We included all randomized controlled trials and quasi-randomized trials that compared music interventions and standard care with standard care alone for persons with confirmed CHD. Data collection and analysis Two review authors independently extracted data and assessed methodological quality, seeking additional information from the trial researchers when necessary. We present results using weighted mean differences for outcomes measured by the same scale, and standardized mean differences for outcomes measured by different scales. We used post-intervention scores. In cases of significant baseline difference, we used change scores (changes from baseline). Main results We identified four new trials for this update. In total, the evidence for this review rests on 26 trials (1369 participants). Listening to music was the main intervention used, and 23 of the studies did not include a trained music therapist. Results indicate that music interventions have a small beneficial effect on psychological distress in people with CHD and this effect is consistent across studies (MD = -1.26, 95% CI -2.30 to -0.22, P = 0.02, I² = 0%). Listening to music has a moderate effect on anxiety in people with CHD; however results were inconsistent across studies (SMD = -0.70, 95% CI -1.17 to -0.22, P = 0.004, I² = 77%). Studies that used music interventions in people with myocardial infarction found more consistent anxiety-reducing effects of music, with an average anxiety reduction of 5.87 units on a 20 to 80 point score range (95% CI -7.99 to -3.75, P < 0.00001, I² = 53%). Furthermore, studies that used patient-selected music resulted in greater anxiety-reducing effects that were consistent across studies (SMD = -0.89, 95% CI -1.42 to -0.36, P = 0.001, I² = 48%). Findings indicate that listening to music reduces heart rate (MD = -3.40, 95% CI -6.12 to -0.69, P = 0.01), respiratory rate (MD = -2.50, 95% CI -3.61 to -1.39, P < 0.00001) and systolic blood pressure (MD = -5.52 mmHg, 95% CI - 7.43 to -3.60, P < 0.00001). Studies that included two or more music sessions led to a small and consistent pain-reducing effect (SMD = -0.27, 95% CI -0.55 to -0.00, P = 0.05). The results also suggest that listening to music may improve patients' quality of sleep following a cardiac procedure or surgery (SMD = 0.91, 95% CI 0.03 to 1.79, P = 0.04). We found no strong evidence for heart rate variability and depression. Only one study considered hormone levels and quality of life as an outcome variable. A small number of studies pointed to a possible beneficial effect of music on opioid intake after cardiac procedures or surgery, but more research is needed to strengthen this evidence. Authors' conclusions This systematic review indicates that listening to music may have a beneficial effect on anxiety in persons with CHD, especially those with a myocardial infarction. Anxiety-reducing effects appear to be greatest when people are given a choice of which music to listen to. Furthermore, listening to music may have a beneficial effect on systolic blood pressure, heart rate, respiratory rate, quality of sleep and pain in persons with CHD. However, the clinical significance of these findings is unclear. Since many of the studies are at high risk of bias, these findings need to be interpreted with caution. More research is needed into the effects of music interventions offered by a trained music therapist.

Inadequate T follicular cell help impairs B cell immunity during HIV infection

Abstract: B cell responses are impaired in HIV-infected individuals. Elias Haddad and colleagues now report that follicular helper T (TFH) cells, which are crucial for the maturation of B cell memory and development of high-affinity antibodies, are functionally impaired upon interaction with lymph node germinal center B cells from HIV-infected individuals. The interaction of the inhibitory molecule PD-1 on TFH cells with its ligand PD-L1, which is elevated on germinal center B cells in HIV-infected lymph nodes, impairs TFH cell proliferation and antibody production by B cells, thus providing insight into humoral dysfunction in HIV infection.

Wintertime aerosol chemical composition and source apportionment of the organic fraction in the metropolitan area of Paris

Abstract: The effect of a post-industrial megacity on local and regional air quality was assessed via a month-long field measurement campaign in the Paris metropolitan area during winter 2010. Here we present source apportionment results from three aerosol mass spectrometers and two aethalometers deployed at three measurement stations within the Paris region. Submicron aerosol composition is dominated by the organic fraction (30-36%) and nitrate (28-29%), with lower contributions from sulfate (14-16%), ammonium (12-14%) and black carbon (7-13%). Organic source apportionment was performed using positive matrix factorization, resulting in a set of organic factors corresponding both to primary emission sources and secondary production. The dominant primary sources are traffic (11-15% of organic mass), biomass burning (13-15%) and cooking (up to 35% during meal hours). Secondary organic aerosol contributes more than 50% to the total organic mass and includes a highly oxidized factor from indeterminate and/or diverse sources and a less oxidized factor related to wood burning emissions. Black carbon was apportioned to traffic and wood burning sources using a model based on wavelength-dependent light absorption of these two combustion sources. The time series of organic and black carbon factors from related sources were strongly correlated. The similarities in aerosol composition, total mass and temporal variation between the three sites suggest that particulate pollution in Paris is dominated by regional factors, and that the emissions from Paris itself have a relatively low impact on its surroundings.

The Diffusion of Policy Diffusion Research in Political Science

Abstract: Over the past fifty years, top political science journals have published hundreds of articles about policy diffusion. This article reports on network analyses of how the ideas and approaches in these articles have spread both within and across the subfields of American politics, comparative politics and international relations. Then, based on a survey of the literature, the who, what, when, where, how and why of policy diffusion are addressed in order to identify and assess some of the main contributions and omissions in current scholarship. It is argued that studies of diffusion would benefit from paying more attention to developments in other subfields and from taking a more systematic approach to tackling the questions of when and how policy diffusion takes place.

The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

Abstract: The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.

TREM2 in neurodegeneration: evidence for association of the p.R47H variant with frontotemporal dementia and Parkinson’s disease

Abstract: Background: A rare variant in the Triggering Receptor Expressed on Myeloid cells 2 (TREM2) gene has been reported to be a genetic risk factor for Alzheimer’s disease by two independent groups (Odds ratio between 2.9-4.5). Given the key role of TREM2 in the effective phagocytosis of apoptotic neuronal cells by microglia, we hypothesized that dysfunction of TREM2 may play a more generalized role in neurodegeneration. With this in mind we set out to assess the genetic association of the Alzheimer’s disease-related risk variant in TREM2 (rs75932628, p.R47H) with other related neurodegenerative disorders. Results: The study included 609 patients with frontotemporal dementia, 765 with amyotrophic lateral sclerosis, 1493 with Parkinson’s disease, 772 with progressive supranuclear palsy, 448 with ischemic stroke and 1957 controls subjects free of neurodegenerative disease. A significant association was observed for the TREM2 p.R47H substitution in susceptibility to frontotemporal dementia (OR = 5.06; p-value = 0.001) and Parkinson’ sd isease (OR =2 .67; p-value = 0.026), while no evidence of association with risk of amyotrophic lateral sclerosis, progressive supranuclear palsy or ischemic stroke was observed. Conclusions: Our results suggest that the TREM2 p.R47H substitution is a risk factor for frontotemporal dementia and Parkinson’s disease in addition to Alzheimer’s disease. These findings suggest a more general role for TREM2 dysfunction in neurodegeneration, which could be related to its role in the immune response.