2,484 research outputs found
Atomic Level Strain Induced by Static and Dynamic Oxygen Vacancies on Reducible Oxide Surfaces
Surface strain often controls properties of the material including charge
transport and chemical reactivity. Localized surface strain is measured with
atomic resolution on (111) ceria nanoparticle surfaces using environmental
transmission electron microscopy under different redox conditions. Density
Functional Theory (DFT) coupled with TEM image simulations have been used for
aid in interpreting the experimental data. Oxygen vacancy creation/annihilation
introduces strain at surface and near surface regions on cation sublattice.
Static and fluxional strainmaps are generated from images at these different
conditions and compared. While fluxional strain is highest at locations
associated with unstable vacancies at active sites, highly inhomogeneous static
strain fields comprising of alternating tensile/compressing strain is seen at
surface and subsurfaces linked to the presence of stable oxygen vacancies.
Interestingly, both stable and unstable oxygen vacancies are found within a few
atomic spacing of each other on the same surface. The static strain pattern
depends on the ambient inside TEM. Oxidizing environments tend to lower vacancy
concentrations at the surface whereas a highly reducing environment created
using high electron dose creates oxygen vacancies everywhere (bulk and
surfaces) in the nanoparticle
Identification of plasma and urinary metabolites and catabolites derived from orange juice (poly)phenols: analysis by high-performance liquid chromatographyâhigh-resolution mass spectrometry
Orange juice is a rich source of (poly)phenols, in particular, the flavanones hesperetin-7-O-rutinoside and naringenin-7-O-rutinoside. Following the acute consumption of 500 mL of orange juice containing 398 ÎŒmol of (poly)phenols by 12 volunteers, 0â24 h plasma and urine samples were analyzed by targeted high-performance liquid chromatographyâhigh-resolution mass spectrometry in order to identify flavanone metabolites and phenolic acid and aromatic catabolites. A total of 19 flavanone metabolitesâcomprising di-O-glucuronide, O-glucuronide, O-glucuronyl-sulfate, and sulfate derivatives of hesperetin, naringenin, and eriodictyolâand 65 microbial-derived phenolic catabolites, such as phenylpropanoid, phenylpropionic, phenylacetic, benzoic, and hydroxycarboxylic acids and benzenetriol and benzoylglycine derivatives, including free phenolics and phase II sulfate, glucuronide, and methyl metabolites, were identified or partially identified in plasma and/or urine samples. The data obtained provide a detailed evaluation of the fate of orange juice (poly)phenols as they pass through the gastrointestinal tract and are absorbed into the circulatory system prior to renal excretion. Potential pathways for these conversions are proposed
Chimpanzee Rights: The Philosophers' Brief
In December 2013, the Nonhuman Rights Project (NhRP) filed a petition for a common law writ of habeas corpus in the New York State Supreme Court on behalf of Tommy, a chimpanzee living alone in a cage in a shed in rural New York (Barlow, 2017). Under animal welfare laws, Tommyâs owners, the Laverys, were doing nothing illegal by keeping him in those conditions. Nonetheless, the NhRP argued that given the cognitive, social, and emotional capacities of chimpanzees, Tommyâs confinement constituted a profound wrong that demanded remedy by the courts. Soon thereafter, the NhRP filed habeas corpus petitions on behalf of Kiko, another chimpanzee housed alone in Niagara Falls, and Hercules and Leo, two chimpanzees held in
research facilities at Stony Brook University. Thus began the legal struggle to move these chimpanzees from captivity to a sanctuary, an effort that has led the NhRP to argue in multiple courts before multiple judges. The central point of contention has been whether Tommy, Kiko, Hercules, and Leo have legal rights. To date, no judge has been willing to issue a writ of habeas corpus on their behalf. Such a ruling would mean that these chimpanzees have rights that confinement might violate. Instead, the judges have argued that chimpanzees cannot be bearers of legal rights because they are not, and cannot be persons. In this book we argue that chimpanzees are persons because they are autonomous
Building governance and energy efficiency: Mapping the interdisciplinary challenge
Improving the energy efficiency of multi-owned properties (MoPs)âcommonly known as apartment or condominium buildingsâis central to the achievement of European energy targets. However, little work to date has focused on how to facilitate retrofit in this context. Drawing on interdisciplinary Social Sciences and Humanities expertise in academia, policy and practice, this chapter posits that decision-making processes within MoPs might provide a key to the retrofit challenge. Existing theories or models of decision-making, applied in the MoP context, might help to explain how collective retrofit decisions are takenâor overlooked. Insights from case studies and practitioners are also key. Theories of change might then be employed to develop strategies to facilitate positive retrofit decisions. The chapter maps the issues and sets an agenda for further interdisciplinary research in this novel area
Childhood vascular phenotypes have differing associations with pre- and postnatal growth
Objective:
In children aged 8--9 years, we examined the associations of linear and abdominal circumference growth during critical stages of prenatal and postnatal development with six vascular measurements commonly used as early markers of atherosclerosis and later cardiovascular disease (CVD) risk.
Methods:
In 724 children from the UK Southampton Women's Survey mother--offspring cohort, offspring length/height and abdominal circumference measurements were collected at 10 ages between 11 weeksâ gestation and age 8--9 years. Using residual growth modelling and linear regression, we examined the independent associations between growth and detailed vascular measures made at 8--9 years.
Results:
Postnatal linear and abdominal circumference growth were associated with higher childhood SBP and carotid--femoral pulse wave velocity, whereas prenatal growth was not. For example, 1SD faster abdominal circumference gain between ages 3 and 6 years was associated with 2.27 [95% confidence interval (CI): 1.56--2.98] mmHg higher SBP. In contrast, faster abdominal circumference gain before 19 weeksâ gestation was associated with greater carotid intima--media thickness [0.009 mm (0.004--0.015) per 1SD larger 19-week abdominal circumference), whereas later growth was not. We found no strong associations between prenatal or postnatal growth and DBP or measures of endothelial function.
Conclusion:
Higher postnatal linear growth and adiposity gain are related to higher SBP and carotid--femoral pulse wave velocity in childhood. In contrast, faster growth in early gestation is associated with greater childhood carotid intima--media thickness, perhaps resulting from subtle changes in vascular structure that reflect physiological adaptations rather than subclinical atherosclerosis
Preoperative systemic inflammation predicts postoperative infectious complications in patients undergoing curative resection for colorectal cancer
The presence of systemic inflammation before surgery, as evidenced by the glasgow prognostic score (mGPS), predicts poor long-term survival in colorectal cancer. The aim was to examine the relationship between the preoperative mGPS and the development of postoperative complications in patients undergoing potentially curative resection for colorectal cancer. Patients (n=455) who underwent potentially curative resections between 2003 and 2007 were assessed consecutively, and details were recorded in a database. The majority of patients presented for elective surgery (85%) were over the age of 65 years (70%), were male (58%), were deprived (53%), and had TNM stage I/II disease (61%), had preoperative haemoglobin (56%), white cell count (87%) and mGPS 0 (58%) in the normal range. After surgery, 86 (19%) patients developed a postoperative complication; 70 (81%) of which were infectious complications. On multivariate analysis, peritoneal soiling (P<0.01), elevated preoperative white cell count (P<0.05) and mGPS (P<0.01) were independently associated with increased risk of developing a postoperative infection. In elective patients, only the mGPS (OR=1.75, 95% CI=1.17-2.63, P=0.007) was significantly associated with increased risk of developing a postoperative infection. Preoperative elevated mGPS predicts increased postoperative infectious complications in patients undergoing potentially curative resection for colorectal cancer
Minimax Current Density Coil Design
'Coil design' is an inverse problem in which arrangements of wire are
designed to generate a prescribed magnetic field when energized with electric
current. The design of gradient and shim coils for magnetic resonance imaging
(MRI) are important examples of coil design. The magnetic fields that these
coils generate are usually required to be both strong and accurate. Other
electromagnetic properties of the coils, such as inductance, may be considered
in the design process, which becomes an optimization problem. The maximum
current density is additionally optimized in this work and the resultant coils
are investigated for performance and practicality. Coils with minimax current
density were found to exhibit maximally spread wires and may help disperse
localized regions of Joule heating. They also produce the highest possible
magnetic field strength per unit current for any given surface and wire size.
Three different flavours of boundary element method that employ different basis
functions (triangular elements with uniform current, cylindrical elements with
sinusoidal current and conic section elements with sinusoidal-uniform current)
were used with this approach to illustrate its generality.Comment: 24 pages, 6 figures, 2 tables. To appear in Journal of Physics D:
Applied Physic
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