1,281 research outputs found
Using Mobile Cameras to Measure Dye Concentration in Bio-Chemistry Experiments
Many cutting edge chemistry experiments for high Âthroughput assays require measuring colored outputs from specially prepared samples. Absorbance from these samples is usually measured with a specialized piece of equipment that adds to the expense, time, and complexity of obtaining experimental results. To make these experiments more accessible, we looked at developing software to allow cell phones or consumer Âgrade USB cameras to measure these experiments and quantify the intensity of the output.
What we have compiled thus far is research regarding several different color spaces and attempted analysis on the many channels of color spaces such as RGB, HSV, HSL, CIELab, CIELuv, XYZ, and YCrCb, that might be used to measure assay results. We concentrated on analyzing the channels and also manipulating the data to find a relationship between the computed color values and concentrations of dye in the assays. We also have created several programs that assist in extracting the channel values from the assays and to sort our results to make analysis easier
Trial by CCN2: a standardized test for fibroproliferative disease?
A major issue concerning clinical trials is the availability of standardized assays to evaluate drug efficacy. Ideally, such assays should test the effect of a putative drug on the expression of a biomarker in biological fluids. In a recent study by Kuiper et al. (PLOS One, 3(7): e2675). The relative levels of vascular endothelial growth factor (VEGF) and CCN2 (connective tissue growth factor [CTGF]) were examined in proliferative diabetic retinopathy (PDR). This paper is the subject of this commentary
Semiparametric posterior corrections
We present a new approach to semiparametric inference using corrected
posterior distributions. The method allows us to leverage the adaptivity,
regularization and predictive power of nonparametric Bayesian procedures to
estimate low-dimensional functionals of interest without being restricted by
the holistic Bayesian formalism. Starting from a conventional nonparametric
posterior, we target the functional of interest by transforming the entire
distribution with a Bayesian bootstrap correction. We provide conditions for
the resulting to possess calibrated frequentist
properties and specialize the results for several canonical examples: the
integrated squared density, the mean of a missing-at-random outcome, and the
average causal treatment effect on the treated. The procedure is
computationally attractive, requiring only a simple, efficient post-processing
step that can be attached onto any arbitrary posterior sampling algorithm.
Using the ACIC 2016 causal data analysis competition, we illustrate that our
approach can outperform the existing state-of-the-art through the propagation
of Bayesian uncertainty.Comment: 53 page
Mouse preimplantation embryo responses to culture medium osmolarity include increased expression of CCM2 and p38 MAPK activation
BACKGROUND: Mechanisms that confer an ability to respond positively to environmental osmolarity are fundamental to ensuring embryo survival during the preimplantation period. Activation of p38 mitogen-activated protein kinase (MAPK) occurs following exposure to hyperosmotic treatment. Recently, a novel scaffolding protein called Osmosensing Scaffold for MEKK3 (OSM) was linked to p38 MAPK activation in response to sorbitol-induced hypertonicity. The human ortholog of OSM is cerebral cavernous malformation 2 (CCM2). The present study was conducted to investigate whether CCM2 is expressed during mouse preimplantation development and to determine whether this scaffolding protein is associated with p38 MAPK activation following exposure of preimplantation embryos to hyperosmotic environments. RESULTS: Our results indicate that Ccm2 along with upstream p38 MAPK pathway constituents (Map3k3, Map2k3, Map2k6, and Map2k4) are expressed throughout mouse preimplantation development. CCM2, MAP3K3 and the phosphorylated forms of MAP2K3/MAP2K6 and MAP2K4 were also detected throughout preimplantation development. Embryo culture in hyperosmotic media increased p38 MAPK activity in conjunction with elevated CCM2 levels. CONCLUSION: These results define the expression of upstream activators of p38 MAPK during preimplantation development and indicate that embryo responses to hyperosmotic environments include elevation of CCM2 and activation of p38 MAPK
An epidemiological study of epilepsy in Hong Kong SAR, China
SummaryBackgroundSeveral specialist clinic-based epidemiology studies suggested low prevalence in Hong Kong Special Administrative Region (HKSAR) of China. Population-based epidemiological data for epilepsy is not available. We performed the first population-based epidemiological survey of epilepsy in this locality.MethodWe conducted a territory-wide survey. We randomly selected 9547 households from fixed-line telephone directory. We successfully surveyed 17,783 persons of 5178 households by telephone interview. All positive respondents 685 (3.85%) were invited for clinical validation. 127 subjects were validated by board-certified neurologists.ResultsSeizure disorders were confirmed in 28 subjects. The crude prevalence of active epilepsy and seizure disorder were estimated to be 3.94/1000 (95% confidence interval (CI): 2.10–6.74/1000) and 8.49/1000 (95% CI: 5.64–12.27/1000), respectively.ConclusionsThe prevalence of epilepsy in HKSAR is more common than previously thought. The data retrieved is useful for planning and allocation of health resources for patients with seizure disorders
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