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https://www.readbyqxmd.com/read/28342981/mechanisms-of-in-vivo-release-of-triamcinolone-acetonide-from-plga-microspheres
#1
Amy C Doty, David G Weinstein, Keiji Hirota, Karl F Olsen, Rose Ackermann, Yan Wang, Stephanie Choi, Steven P Schwendeman
Little is known about the underlying effects controlling in vitro-in vivo correlations (IVIVCs) for biodegradable controlled release microspheres. Most reports of IVIVCs that exist are empirical in nature, typically based on a mathematical relationship between in vitro and in vivo drug release, with the latter often estimated by deconvolution of pharmacokinetic data. In order to improve the ability of in vitro release tests to predict microsphere behavior in vivo and develop more meaningful IVIVCs, the in vivo release mechanisms need to be characterized...
March 22, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28342918/evidence-of-the-impact-of-visuo-spatial-processing-on-magnitude-representation-in-22q11-2-microdeletion-syndrome
#2
Lucie Attout, Marie-Pascale Noël, Line Vossius, Laurence Rousselle
The influence of visuo-spatial skills on numerical magnitude processing is the subject of a long-standing debate. As most of the numerical and non-numerical magnitude abilities underpinning mathematical development are visual by nature, they are often assessed in the visual modality, thereby confusing visuo-spatial and numerical processing. In order to assess the influence of visuo-spatial processing on numerical magnitude representation, we examined magnitude processing in patients with 22q11.2 deletion syndrome (22q11DS), a genetic condition characterized by a cognitive profile with a relative weakness in visuo-spatial abilities but with preserved verbal abilities...
March 22, 2017: Neuropsychologia
https://www.readbyqxmd.com/read/28342844/a-system-dynamics-modelling-approach-to-assess-the-impact-of-launching-a-new-nicotine-product-on-population-health-outcomes
#3
Andrew Hill, Oscar M Camacho
In 2012 the US FDA suggested the use of mathematical models to assess the impact of releasing new nicotine or tobacco products on population health outcomes. A model based on system dynamics methodology was developed to project the potential effects of a new nicotine product at a population level. A model representing traditional smoking populations (never, current and former smokers) and calibrated using historical data was extended to a two-product model by including electronic cigarettes use statuses. Smoking mechanisms, such as product initiation, switching, transition to dual use, and cessation, were represented as flows between smoking statuses (stocks) and the potential effect of smoking renormalisation through a feedback system...
March 22, 2017: Regulatory Toxicology and Pharmacology: RTP
https://www.readbyqxmd.com/read/28342804/easy-to-use-equations-for-the-estimation-of-urine-relative-saturation-in-the-assessment-of-risk-of-recurrence-in-urinary-stones-formers
#4
Geneviève Plante, Denis Ouimet, Robert Robitaille
It is a fact that recurrence of urinary stones is a common medical problem. One of the key factors used in determining the risk of urinary stone-formation is the urine relative saturation in the major constituents of lithiasis. Nomograms were developed in the 1970's to estimate the relative saturation of urine. We present here easy-to-use mathematical equations derived from these nomograms. These equations can be integrated directly in the LIS of any laboratories, and can be used as a tool in the treatment and prevention of recurrent stone-formation...
March 22, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28342717/slow-chromatin-dynamics-allow-polycomb-target-genes-to-filter-fluctuations-in-transcription-factor-activity
#5
Scott Berry, Caroline Dean, Martin Howard
Genes targeted by Polycomb repressive complex 2 (PRC2) are regulated in cis by chromatin modifications and also in trans by diffusible regulators such as transcription factors. Here, we introduce a mathematical model in which transcription directly antagonizes Polycomb silencing, thereby linking these cis- and trans-regulatory inputs to gene expression. The model is parameterized by recent experimental data showing that PRC2-mediated repressive chromatin modifications accumulate extremely slowly. The model generates self-perpetuating, bistable active and repressed chromatin states that persist through DNA replication, thereby ensuring high-fidelity transmission of the current chromatin state...
March 21, 2017: Cell Systems
https://www.readbyqxmd.com/read/28340499/pagan-symbols-associated-with-the-female-anatomy-in-the-medici-chapel-by-michelangelo-buonarroti
#6
Deivis de Campos, Andrea Oxley da Rocha, Rodrigo de Oliveira Lemos, Tais Malysz, João Antonio Bonatto-Costa, Geraldo Pereira Jotz, Lino Pinto de Oliveira Junior, Miriam da Costa Oliveira
Numerous studies have shown that many works of art from the Renaissance period contain hidden symbols and codes that could have religious, mathematical and/or pagan significance and even anatomical allusions. In this context, the present manuscript offers new evidence that the great genius of anatomy, Michelangelo Buonarroti (1475-1564), included pagan symbols associated with female anatomy in the funerary monuments found in the Sagrestia Nuova/Medici Chapel (1519-1533) in Florence, Italy. The interpretation of the symbols provided in this study will interest those with a passion for the history of anatomy...
March 24, 2017: Clinical Anatomy
https://www.readbyqxmd.com/read/28340476/temporal-patterns-of-co2-and-ch4-in-a-rural-area-in-northern-spain-described-by-a-harmonic-equation-over-2010-2016
#7
Beatriz Fernández-Duque, Isidro A Pérez, M Luisa Sánchez, M Ángeles García, Nuria Pardo
The present paper seeks to improve our knowledge concerning the evolution of CO2 and CH4 in terms of monthly trends, growth rate and seasonal variations in the lower atmosphere. Dry continuous measurements of CO2 and the CH4 mixing ratio were carried out over five and a half years (from 15 October 2010 to 29 February 2016) by multi-point sampling at 1.8, 3.7 and 8.3m, using a Picarro analyzer at a rural site in the Low Atmosphere Research Centre (CIBA), on the upper Spanish plateau. Data were divided into diurnal and nocturnal records...
March 21, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28340391/optimization-of-the-marinelli-beaker-dimensions-using-genetic-algorithm
#8
Seyed Mehrdad Zamzamian, Seyed Abolfazl Hosseini, Mohammad Samadfam
A computational code, based on the genetic algorithm and MCNPX version 2.6 code was developed and used to investigate the effects of some important parameters of HPGe detector (such as Al cap thickness, dead-layer thickness and Ge hole size) on optimum dimensions of marinelli beaker. In addition, the effects of detector material on optimal beaker dimensions were also investigated. Finally, the optimized beaker dimensions at various beaker volumes (300, 500, 700, 1000 and 1500 cm(3)) were determined for some conventional Ge detectors with different crystal sizes (16 sizes)...
March 21, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28340243/finite-time-parametric-identification-for-the-model-representing-the-metabolic-and-genetic-regulatory-effects-of-sequential-aerobic-respiration-and-anaerobic-fermentation-processes-in-escherichia-coli
#9
Alfonso Sepúlveda-Gálvez, Jesús Agustín Badillo-Corona, Isaac Chairez
Mathematical modelling applied to biological systems allows for the inferring of changes in the dynamic behaviour of organisms associated with variations in the environment. Models based on ordinary differential equations are most commonly used because of their ability to describe the mechanisms of biological systems such as transcription. The disadvantage of using this approach is that there is a large number of parameters involved and that it is difficult to obtain them experimentally. This study presents an algorithm to obtain a finite-time parameter characterization of the model used to describe changes in the metabolic behaviour of Escherichia coli associated with environmental changes...
March 17, 2017: Mathematical Medicine and Biology: a Journal of the IMA
https://www.readbyqxmd.com/read/28339789/early-treatment-gains-for-antibiotic-administration-and-within-human-host-time-series-data
#10
Todd R Young, Erik M Boczko
As technological improvements continue to infiltrate and impact medical practice, it has become possible to non-invasively collect dense physiological time series data from individual patients in real time. These advances continue to improve physicians' ability to detect and to treat infections early. One important benefit of early detection and treatment of nascent infections is that it leads to earlier resolution. In response to current and anticipated advances in data capture, we introduce the Early Treatment Gain (ETG) as a measure to quantify this benefit...
February 18, 2017: Mathematical Medicine and Biology: a Journal of the IMA
https://www.readbyqxmd.com/read/28339681/on-tear-film-breakup-tbu-dynamics-and-imaging
#11
Richard J Braun, Tobin A Driscoll, Carolyn G Begley, P Ewen King-Smith, Javed I Siddique
We report the results of some recent experiments to visualize tear film dynamics. We then study a mathematical model for tear film thinning and tear film breakup (TBU), a term from the ocular surface literature. The thinning is driven by an imposed tear film thinning rate which is input from in vivo measurements. Solutes representing osmolarity and fluorescein are included in the model. Osmolarity causes osmosis from the model ocular surface, and the fluorescein is used to compute the intensity corresponding closely to in vivo observations...
February 20, 2017: Mathematical Medicine and Biology: a Journal of the IMA
https://www.readbyqxmd.com/read/28339184/mxene-ti3c2-an-effective-2d-light-to-heat-conversion-material
#12
Renyuan Li, Lianbin Zhang, Le Shi, Peng Wang
MXene, a new series of 2D material, has been steadily advancing its applications to a variety of fields, such as catalysis, supercapacitor, molecular separation, electromagnetic wave interference shielding. This work reports a carefully designed aqueous droplet light heating system along with a thorough mathematical procedure, which combined leads to a precise determination of internal light-to-heat conversion efficiency of a variety of nanomaterials. The internal light-to-heat conversion efficiency of MXene, more specifically Ti3C2, was measured to be 100%, indicating a perfect energy conversion...
March 24, 2017: ACS Nano
https://www.readbyqxmd.com/read/28339169/gesp-a-computer-program-for-modeling-genetic-effective-population-size-inbreeding-and-divergence-in-substructured-populations
#13
Fredrik Olsson, Linda Laikre, Ola Hössjer, Nils Ryman
The genetically effective population size (Ne) is of key importance for quantifying rates of inbreeding and genetic drift, and is often used in conservation management to set targets for genetic viability. The concept was developed for single, isolated populations and the mathematical means for analyzing the expected Ne in complex, subdivided populations have previously not been available. We recently developed such analytical theory and central parts of that work have now been incorporated into a freely available software tool presented here...
March 24, 2017: Molecular Ecology Resources
https://www.readbyqxmd.com/read/28339110/a-fast-non-iterative-approach-for-accelerated-high-temporal-resolution-cine-cmr-using-dynamically-interleaved-streak-removal-in-the-power-spectral-encoded-domain-with-low-pass-filtering-dispel-and-modulo-prime-spokes-mops
#14
Keigo Kawaji, Mita B Patel, Charles G Cantrell, Akiko Tanaka, Marco Marino, Satoshi Tamura, Hui Wang, Yi Wang, Timothy J Carroll, Takeyoshi Ota, Amit R Patel
PURPOSE: To introduce a pair of accelerated non-Cartesian acquisition principles that when combined, exploit the periodicity of k-space acquisition, and thereby enable acquisition of high-temporal cine-Cardiac Magnetic Resonance (CMR). METHODS: The mathematical formulation of a non-iterative, undersampled non-Cartesian cine acquisition and reconstruction is presented. First, a low-pass-filtering step that exploits streaking artifact redundancy is provided; (i.e...
March 24, 2017: Medical Physics
https://www.readbyqxmd.com/read/28338948/comparing-measured-and-calculated-doses-in-interventional-cardiology-procedures
#15
M W Oliveira da Silva, L V Canevaro, J Hunt, B B D Rodrigues
Interventional cardiology requires complex procedures and can result in high doses and dose rates to the patient and medical staff. The many variables that influence the dose to the patient and staff include the beam position and angle, beam size, kVp, filtration, kerma-area product and focus-skin distance. A number of studies using the Monte Carlo method have been undertaken to obtain prospective dose assessments. In this paper, detailed irradiation scenarios were simulated mathematically and the resulting dose estimates were compared with real measurements made previously under very similar irradiation conditions and geometries...
March 16, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/28338412/adolescent-changes-in-aerobic-fitness-are-related-to-changes-in-academic-achievement
#16
Lauren B Raine, John R Biggan, Carol L Baym, Brian J Saliba, Neal J Cohen, Charles H Hillman
There is a growing trend of decreasing physical fitness among adolescents, which may not only result in poorer physical health, but also poorer academic achievement. PURPOSE: The purpose of this study was to investigate the changes in aerobic fitness and academic achievement in reading and mathematics during middle school. METHOD: This study employed a prospective, longitudinal cross-sectional design. Fifty-two adolescents were followed from sixth grade through eighth grade...
March 24, 2017: Pediatric Exercise Science
https://www.readbyqxmd.com/read/28338400/systematic-unintended-drifts-in-the-cyclic-force-produced-with-the-fingertips
#17
Satyajit Ambike, Daniela Mattos, Vladimir M Zatsiorsky, Mark Latash
Cyclic isometric finger-force patterns established using visual feedback show systematic drifts when the feedback is removed. Force changes at multiple time scales and opposite directions have been reported. For further characterization of these drifts, healthy subjects produced isometric, cyclic finger force with and without visual feedback at various initial amplitudes and frequencies. We hypothesized that on feedback removal, the amplitude will be attracted towards a preferred value that is frequency dependent...
March 24, 2017: Motor Control
https://www.readbyqxmd.com/read/28338079/dissecting-mirna-gene-repression-on-single-cell-level-with-an-advanced-fluorescent-reporter-system
#18
Nicolas Lemus-Diaz, Kai O Böker, Ignacio Rodriguez-Polo, Michael Mitter, Jasmin Preis, Maximilian Arlt, Jens Gruber
Despite major advances on miRNA profiling and target predictions, functional readouts for endogenous miRNAs are limited and frequently lead to contradicting conclusions. Numerous approaches including functional high-throughput and miRISC complex evaluations suggest that the functional miRNAome differs from the predictions based on quantitative sRNA profiling. To resolve the apparent contradiction of expression versus function, we generated and applied a fluorescence reporter gene assay enabling single cell analysis...
March 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28337911/mathematical-model-of-serodiagnostic-immunochromatographic-assay
#19
Dmitriy V Sotnikov, Anatoly V Zherdev, Boris B Dzantiev
This article describes the mathematical model for an immunochromatographic assay for the detection of specific immunoglobulins against a target antigen (antibodies) in blood/serum (serodiagnosis). The model utilizes an analytical (non-numerical) approach and allows the calculation of the kinetics of immune complexes' formation in a continuous-flow system using commonly available software, such as Microsoft Excel. The developed model could identify the nature of the influence of immunochemical interaction constants and reagent concentrations on the kinetics of the formation of the detected target complex...
March 24, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28336358/assessing-hemispheric-specialization-for-processing-arithmetic-skills-in-adults-a-functional-transcranial-doppler-ultrasonography-ftcd-study
#20
Veronica M Connaughton, Azhani Amiruddin, Karen L Clunies-Ross, Noel French, Allison M Fox
BACKGROUND: A major model of the cerebral circuits that underpin arithmetic calculation is the triple-code model of numerical processing. This model proposes that the lateralization of mathematical operations is organized across three circuits: a left-hemispheric dominant verbal code; a bilateral magnitude representation of numbers and a bilateral Arabic number code. NEW METHOD: This study simultaneously measured the blood flow of both middle cerebral arteries using functional transcranial Doppler ultrasonography to assess hemispheric specialization during the performance of both language and arithmetic tasks...
March 20, 2017: Journal of Neuroscience Methods
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