2,477 research outputs found
Descriptions of new fishes from Panama
The following preliminary descriptions are of new fishes obtained by the authors during their first season's work on the Biological Survey of the Canal Zone, the ichthyological work of which is being conducted cooperatively by the Field Museum of Natural History and the Smithsonian Institution. (2 page document
A traveling wave decelerator for neutral polar molecules
Recently, a decelerator for neutral polar molecules has been presented that
operates on the basis of macroscopic, three-dimensional, traveling
electrostatic traps (Osterwalder et al., Phys. Rev. A 81, 051401 (2010)). In
the present paper, a complete description of this decelerator is given, with
emphasis on the electronics and the mechanical design. Experimental results
showing the transverse velocity distributions of guided molecules are shown and
compared to trajectory simulations. An assessment of non-adiabatic losses is
made by comparing the deceleration signals from 13-CO with those from 12-CO and
with simulated signals.Comment: 10 pages, 7 figure
Training Psychologists to Work With Religious Organizations: The Center for Church-Psychology Collaboration
Church-psychology collaboration is gaining attention among professional psychologists, but few training or practical research opportunities are available for those interested in collaborating with religious leaders and organizations. The authors introduce the Center for Church-Psychology Collaboration (CCPC), with its mission to make sustained and relevant contributions to the research literature in psychology, train doctoral students in effective means of collaborating with religious organizations, and provide service to religious communities throughout the world. Domestic and global implications are discussed
Effects of amino acids and glucose on mesangial cell aminopeptidase a and angiotensin receptors
Effects of amino acids and glucose on mesangial cell aminopeptidase a and angiotensin receptors.BackgroundHigh protein diets and diabetes increase renal renin angiotensin system (RAS) activity, which is associated with glomerular injury. Aminopeptidase A (APA) is a cell surface metalloprotease that degrades angiotensin II (AII) in the mesangium. Mesangial cells (MC) also possess receptors for AII; the type 1 (AT1 receptor) promotes proliferation and fibrosis, while the type 2 (AT2 receptor) opposes these effects. We evaluated whether amino acids and glucose alter expression of APA, AT1 receptor and AT2 receptor in a manner that further augments RAS activity.MethodsConfluent rat MC were grown in serum-free media for 48 hours prior to exposing to experimental conditions: control (C), high amino acids (HA, mixed amino acid solution added to raise concentrations 5- to 6-fold over C), high glucose (HG 30, mM glucose). Semi-quantitative RT-PCR was used to assess mRNA for APA, AT1 receptor, AT2 receptor, and β-actin. Values are expressed relative to βbgr; actin.ResultsBoth HA and HG reduced APA mRNA (HG 1.13 ± 0.19, HA 1.12 ± 0.16 versus C 1.27 ± 0.16 P < 0.05, N = 8). HA increased AT1 receptor mRNA (HA 2.11 ± 0.43 versus C 1.14 ± 0.28 P < 0.05, N = 8). HG increased AT2 receptor mRNA (HG 1.31 ± 0.43 versus C 0.82 ± 0.33 P < 0.05, N = 6).ConclusionsA reduction of APA, in response to high levels of amino acids or glucose, could contribute to increased AII as a result of decreased degradation in MC. The effect of amino acids to increase AT1 receptor expression may further enhance adverse hemodynamic and pro-fibrotic actions of AII. Conversely, glucose increased AT2 receptor expression, which could modulate responses mediated by the AT1 receptor
Smartphone screening for neonatal jaundice via ambient-subtracted sclera chromaticity
Jaundice is a major cause of mortality and morbidity in the newborn. Globally, early identification and home monitoring are significant challenges in reducing the incidence of jaundice-related neurological damage. Smartphone cameras are promising as colour-based screening tools as they are low-cost, objective and ubiquitous. We propose a novel smartphone method to screen for neonatal jaundice by imaging the sclera. It does not rely on colour calibration cards or accessories, which may facilitate its adoption at scale and in less economically developed regions. Our approach is to explicitly address three confounding factors in relating colour to jaundice: (1) skin pigmentation, (2) ambient light, and (3) camera spectral response. (1) The variation in skin pigmentation is avoided by imaging the sclera. (2) With the smartphone screen acting as an illuminating flash, a flash/ no-flash image pair is captured using the front-facing camera. The contribution of ambient light is subtracted. (3) In principle, this permits a device- and ambient-independent measure of sclera chromaticity following a one-time calibration. We introduce the concept of Scleral-Conjunctival Bilirubin (SCB), in analogy with Transcutaneous Bilirubin (TcB). The scleral chromaticity is mapped to an SCB value. A pilot study was conducted in the UCL Hospital Neonatal Care Unit (n = 37). Neonates were imaged using a specially developed app concurrently with having a blood test for total serum bilirubin (TSB). The better of two models for SCB based on ambient-subtracted sclera chromaticity achieved r = 0.75 (p250ÎĽmol/L (area under receiver operating characteristic curve, AUROC, 0.86), and 92% (specificity 67%) in identifying newborns with TSB>205ÎĽmol/L (AUROC 0.85). These results are comparable to modern transcutaneous bilirubinometers
Teleological Essentialism
Placeholder essentialism is the view that there is a causal essence that holds category members together, though we may not know what the essence is. Sometimes the placeholder can be filled in by scientific essences, such as when we acquire scientific knowledge that the atomic weight of gold is 79. We challenge the view that placeholders are elaborated by scientific essences. On our view, if placeholders are elaborated, they are elaborated Aristotelian essences, a telos. Utilizing the same kinds of experiments used by traditional essentialists—involving superficial change (study 1), transformation of insides (study 2), acquired traits (study 3) and inferences about offspring (study 4)—we find support for the view that essences are elaborated by a telos. And we find evidence (study 5) that teleological essences may generate category judgments
Smartphone colorimetry using ambient subtraction: Application to neonatal jaundice screening in Ghana
A smartphone app to screen for neonatal jaundice has a large
potential impact in reducing neonatal death and disability.
Our app, neoSCB, uses a colour measurement of the sclera
to make a screening decision. Although there are numerous
benefits of a smartphone-based approach, smartphone colour
measurement that is accurate and repeatable is a challenge.
Using data from a clinical setting in Ghana, we compare
sclera colour measurement using an ambient subtraction
method to sclera colour measurement using a standard colour
card method, and find they are comparable provided the subtracted signal-to-noise ratio (SSNR) is sufficient. Calculating
a screening decision metric via the colour card method gave
100% sensitivity and 69% specificity (n=87), while applying
the ambient subtraction method gave 100% sensitivity and
78% specificity (SSNR>3.5; n=50)
Particle-in-cell simulations of rf breakdown
Breakdown voltages of a capacitively coupled radio frequency argon discharge
at 27 MHz are studied. We use a one-dimensional electrostatic PIC code to
investigate the effect of changing the secondary emission properties of the
electrodes on the breakdown voltage, particularly at low pd values. Simulation
results are compared with the available experimental results and a satisfactory
agreement is found.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004,
Nice (France
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