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https://www.readbyqxmd.com/read/27911370/integrated-compensatory-responses-in-a-human-model-of-hemorrhage
#1
Victor A Convertino, Carmen Hinojosa-Laborde, Gary W Muniz, Robert Carter
Hemorrhage is the leading cause of trauma-related deaths, partly because early diagnosis of the severity of blood loss is difficult. Assessment of hemorrhaging patients is difficult because current clinical tools provide measures of vital signs that remain stable during the early stages of bleeding due to compensatory mechanisms. Consequently, there is a need to understand and measure the total integration of mechanisms that compensate for reduced circulating blood volume and how they change during ongoing progressive hemorrhage...
November 20, 2016: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/27911354/a-spectral-interior-ct-by-a-framelet-based-reconstruction-algorithm
#2
Yingmei Wang, Ge Wang, Shuwei Mao, Wenxiang Cong, Zhilong Ji, Jian-Feng Cai, Yangbo Ye
Reducing radiation dose is an important goal in medical computed tomography (CT), for which interior tomography is an effective approach. There have been interior reconstruction algorithms for monochromatic CT, but in reality, X-ray sources are polychromatic. Using a polychromatic acquisition model and motivated by framelet-based image processing algorithms, in this paper, we propose an interior reconstruction algorithm to obtain an image with spectral information assuming only one scan with a current energy-integrating detector...
November 22, 2016: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/27911353/computer-aided-classification-of-mammographic-masses-using-visually-sensitive-image-features
#3
Yunzhi Wang, Faranak Aghaei, Ali Zarafshani, Yuchen Qiu, Wei Qian, Bin Zheng
PURPOSE: To develop a new computer-aided diagnosis (CAD) scheme that computes visually sensitive image features routinely used by radiologists to develop a machine learning classifier and distinguish between the malignant and benign breast masses detected from digital mammograms. METHODS: An image dataset including 301 breast masses was retrospectively selected. From each segmented mass region, we computed image features that mimic five categories of visually sensitive features routinely used by radiologists in reading mammograms...
November 30, 2016: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/27911345/computing-the-influences-of-different-intraocular-pressures-on-the-human-eye-components-using-computational-fluid-structure-interaction-model
#4
Alireza Karimi, Reza Razaghi, Mahdi Navidbakhsh, Toshihiro Sera, Susumu Kudo
BACKGROUND: Intraocular Pressure (IOP) is defined as the pressure of aqueous in the eye. It has been reported that the normal range of IOP should be within the 10-20 mmHg with an average of 15.50 mmHg among the ophthalmologists. Keratoconus is an anti-inflammatory eye disorder that debilitated cornea unable to reserve the normal structure contrary to the IOP in the eye. Consequently, the cornea would bulge outward and invoke a conical shape following by distorted vision. In addition, it is known that any alterations in the structure and composition of the lens and cornea would exceed a change of the eye ball as well as the mechanical and optical properties of the eye...
November 25, 2016: Technology and Health Care: Official Journal of the European Society for Engineering and Medicine
https://www.readbyqxmd.com/read/27911329/comparison-of-model-based-indices-of%C3%A2-cerebral-autoregulation-and-vasomotor-reactivity-using-transcranial-doppler-versus-near-infrared-spectroscopy-in%C3%A2-patients-with-amnestic-mild-cognitive-impairment
#5
Vasilis Z Marmarelis, Dae C Shin, Takashi Tarumi, Rong Zhang
We recently introduced model-based "physiomarkers" of dynamic cerebral autoregulation and CO2 vasomotor reactivity as an aid for diagnosis of early-stage Alzheimer's disease (AD) [1], where significant impairment of dynamic vasomotor reactivity (DVR) was observed in early-stage AD patients relative to age-matched controls. Milder impairment of DVR was shown in patients with amnestic mild cognitive impairment (MCI) using the same approach in a subsequent study [2]. The advocated approach utilizes subject-specific data-based models of cerebral hemodynamics to quantify the dynamic effects of resting-state changes in arterial blood pressure and end-tidal CO2 (the putative inputs) upon cerebral blood flow velocity (the putative output) measured at the middle cerebral artery via transcranial Doppler (TCD)...
November 28, 2016: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/27911129/socioeconomic-position-and-mortality-among-patients-with-prostate-cancer-influence-of-mediating-factors
#6
Signe Benzon Larsen, Klaus Brasso, Jane Christensen, Christoffer Johansen, Anne Tjønneland, Søren Friis, Peter Iversen, Susanne Oksbjerg Dalton
INTRODUCTION: Men with low socioeconomic position experience higher mortality after a prostate cancer diagnosis compared to men with a higher socioeconomic position, however, the specific mediators of this association are unclear. We therefore evaluated the influence of potential mediators on the association between socioeconomic position, and prostate cancer-specific and all-cause death in prostate cancer patients. MATERIALS AND METHODS: We conducted a cohort study of prostate cancer patients in the Danish Diet, Cancer and Health study...
December 2, 2016: Acta Oncologica
https://www.readbyqxmd.com/read/27910992/tug-of-war-between-two-elastically-coupled-molecular-motors-a-case-study-on-force-generation-and-force-balance
#7
Mehmet Can Uçar, Reinhard Lipowsky
Intracellular transport is performed by molecular motors that pull cargos along cytoskeletal filaments. Many cellular cargos are observed to move bidirectionally, with fast transport in both directions. This behaviour can be understood as a stochastic tug-of-war between two teams of antagonistic motors. The first theoretical model for such a tug-of-war, the Müller-Klumpp-Lipowsky (MKL) model, was based on two simplifying assumptions: (i) both motor teams move with the same velocity in the direction of the stronger team, and (ii) this velocity matching and the associated force balance arise immediately after the rebinding of an unbound motor to the filament...
December 2, 2016: Soft Matter
https://www.readbyqxmd.com/read/27910837/accurate-and-efficient-representation-of-intramolecular-energy-in-ab-initio-generation-of-crystal-structures-i-adaptive-local-approximate-models
#8
Isaac Sugden, Claire S Adjiman, Constantinos C Pantelides
The global search stage of crystal structure prediction (CSP) methods requires a fine balance between accuracy and computational cost, particularly for the study of large flexible molecules. A major improvement in the accuracy and cost of the intramolecular energy function used in the CrystalPredictor II [Habgood et al. (2015). J. Chem. Theory Comput. 11, 1957-1969] program is presented, where the most efficient use of computational effort is ensured via the use of adaptive local approximate model (LAM) placement...
December 1, 2016: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/27910829/optimization-of-photon-beam-energies-in-gold-nanoparticle-enhanced-arc-radiation-therapy-using-monte-carlo-methods
#9
B Koger, C Kirkby
As a recent area of development in radiation therapy, gold nanoparticle (GNP) enhanced radiation therapy has shown potential to increase tumour dose while maintaining acceptable levels of healthy tissue toxicity. In this study, the effect of varying photon beam energy in GNP enhanced arc radiation therapy (GEART) is quantified through the introduction of a dose scoring metric, and GEART is compared to a conventional radiotherapy treatment. The PENELOPE Monte Carlo code was used to model several simple phantoms consisting of a spherical tumour containing GNPs (concentration: 15 mg Au g(-1) tumour, 0...
December 2, 2016: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/27910712/development-of-a-nanogel-formulation-for-transdermal-delivery-of-tenoxicam-a-pharmacokinetic-pharmacodynamic-modeling-approach-for-quantitative-prediction-of-skin-absorption
#10
Mohammed H Elkomy, Shahira F El Menshawe, Hussein M Eid, Ahmed M A Ali
This study investigates potentials of solid lipid nanoparticles (SLN) based gel for transdermal delivery of tenoxicam (TNX) and describes a pharmacokinetics-pharmacodynamics (PK-PD) modeling approach for predicting concentration-time profile in skin. A 2(3) factorial design was adopted to study the effect of formulation factors on SLN properties and determine the optimal formulation. SLN-gel tolerability was investigated using rabbit skin irritation test. Its anti-inflammatory activity was assessed by carrageenan induced rat paw edema test...
December 2, 2016: Drug Development and Industrial Pharmacy
https://www.readbyqxmd.com/read/27910650/full-wave-feasibility-study-of-anti-radar-diagnostic-of-magnetic-field-based-on-o-x-mode-conversion-and-oblique-reflectometry-imaging
#11
Orso Meneghini, Francesco A Volpe
An innovative millimeter wave diagnostic is proposed to measure the local magnetic field and edge current as a function of the minor radius in the tokamak pedestal region. The idea is to identify the direction of minimum reflectivity at the O-mode cutoff layer. Correspondingly, the transmissivity due to O-X mode conversion is maximum. That direction, and the angular map of reflectivity around it, contains information on the magnetic field vector B at the cutoff layer. Probing the plasma with different wave frequencies provides the radial profile of B...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910465/accelerated-reconstruction-of-electrical-impedance-tomography-images-via-patch-based-sparse-representation
#12
Qi Wang, Zhijie Lian, Jianming Wang, Qingliang Chen, Yukuan Sun, Xiuyan Li, Xiaojie Duan, Ziqiang Cui, Huaxiang Wang
Electrical impedance tomography (EIT) reconstruction is a nonlinear and ill-posed problem. Exact reconstruction of an EIT image inverts a high dimensional mathematical model to calculate the conductivity field, which causes significant problems regarding that the computational complexity will reduce the achievable frame rate, which is considered as a major advantage of EIT imaging. The single-step method, state estimation method, and projection method were always used to accelerate reconstruction process. The basic principle of these methods is to reduce computational complexity...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910417/new-numerical-simulation-method-to-calibrate-the-regular-hexagonal-nai-tl-detector-with-radioactive-point-sources-situated-non-axial
#13
Ayman Hamzawy, Dimitar N Grozdanov, Mohamed S Badawi, Fuad A Aliyev, Abouzeid A Thabet, Mahmoud I Abbas, Ivan N Ruskov, Ahmed M El-Khatib, Yuri N Kopatch, Mona M Gouda
Scintillation crystals are usually used for detection of energetic photons at room temperature in high energy and nuclear physics research, non-destructive analysis of materials testing, safeguards, nuclear treaty verification, geological exploration, and medical imaging. Therefore, new designs and construction of radioactive beam facilities are coming on-line with these science brunches. A good number of researchers are investigating the efficiency of the γ-ray detectors to improve the models and techniques used in order to deal with the most pressing problems in physics research today...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910396/four-dimensional-4d-tracking-of-high-temperature-microparticles
#14
Zhehui Wang, Q Liu, W Waganaar, J Fontanese, D James, T Munsat
High-speed tracking of hot and molten microparticles in motion provides rich information about burning plasmas in magnetic fusion. An exploding-wire apparatus is used to produce moving high-temperature metallic microparticles and to develop four-dimensional (4D) or time-resolved 3D particle tracking techniques. The pinhole camera model and algorithms developed for computer vision are used for scene calibration and 4D reconstructions. 3D positions and velocities are then derived for different microparticles...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910111/cystatin-c-and-epicardial-adipose-tissue-as-noninvasive-predictors-of-cardiovascular-risk-in-acromegaly
#15
Anna Aulinas, Iris Crespo, David Viladés, Ruben Leta, Eulàlia Urgell, Betina Biagetti, Susan M Webb, Elena Valassi
BACKGROUND: Acromegaly (ACRO) is associated with elevated cardiovascular risk, although the prevalence of coronary artery disease (CAD) is unclear. Increased epicardial adipose tissue (EAT) and elevated cystatin-C (Cys-C) levels are cardiovascular risk factors, also related to the progression of CAD in several populations. AIMS: To measure the severity and extent of CAD in patients with ACRO and to determine whether either EAT or Cys-C reflect higher cardiovascular risk in patients with ACRO than in healthy controls...
November 7, 2016: Clinical Endocrinology
https://www.readbyqxmd.com/read/27910109/electronic-absorption-spectra-of-pyridine-and-nicotine-in-aqueous-solution-with-a-combined-molecular-dynamics-and-polarizable-qm-mm-approach
#16
Marco Pagliai, Giordano Mancini, Ivan Carnimeo, Nicola De Mitri, Vincenzo Barone
The electronic absorption spectra of pyridine and nicotine in aqueous solution have been computed using a multistep approach. The computational protocol consists in studying the solute solvation with accurate molecular dynamics simulations, characterizing the hydrogen bond interactions, and calculating electronic transitions for a series of configurations extracted from the molecular dynamics trajectories with a polarizable QM/MM scheme based on the fluctuating charge model. Molecular dynamics simulations and electronic transition calculations have been performed on both pyridine and nicotine...
December 2, 2016: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/27910103/reliability-and-concurrent-validity-of-a-new-iphone-%C3%A2-goniometric-application-for-measuring-active-wrist-range-of-motion-a-cross-sectional-study-in-asymptomatic-subjects
#17
Mohammad Reza Pourahmadi, Ismail Ebrahimi Takamjani, Javad Sarrafzadeh, Mehrdad Bahramian, Mohammad Ali Mohseni-Bandpei, Fatemeh Rajabzadeh, Morteza Taghipour
Measurement of wrist range of motion (ROM) is often considered to be an essential component of wrist physical examination. The measurement can be carried out through various instruments such as goniometers and inclinometers. Recent smartphones have been equipped with accelerometers and magnetometers, which, through specific software applications (apps) can be used for goniometric functions. This study, for the first time, aimed to evaluate the reliability and concurrent validity of a new smartphone goniometric app (Goniometer Pro©) for measuring active wrist ROM...
December 2, 2016: Journal of Anatomy
https://www.readbyqxmd.com/read/27909942/experiment-design-for-nonparametric-models-based-on-minimizing-bayes-risk-application-to-voriconazole-formula-see-text
#18
David S Bayard, Michael Neely
An experimental design approach is presented for individualized therapy in the special case where the prior information is specified by a nonparametric (NP) population model. Here, a NP model refers to a discrete probability model characterized by a finite set of support points and their associated weights. An important question arises as to how to best design experiments for this type of model. Many experimental design methods are based on Fisher information or other approaches originally developed for parametric models...
December 1, 2016: Journal of Pharmacokinetics and Pharmacodynamics
https://www.readbyqxmd.com/read/27909940/enhancement-of-rapamycin-production-by-metabolic-engineering-in-streptomyces-hygroscopicus-based-on-genome-scale-metabolic-model
#19
Lanqing Dang, Jiao Liu, Cheng Wang, Huanhuan Liu, Jianping Wen
Rapamycin, as a macrocyclic polyketide with immunosuppressive, antifungal, and anti-tumor activity produced by Streptomyces hygroscopicus, is receiving considerable attention for its significant contribution in medical field. However, the production capacity of the wild strain is very low. Hereby, a computational guided engineering approach was proposed to improve the capability of rapamycin production. First, a genome-scale metabolic model of Streptomyces hygroscopicus ATCC 29253 was constructed based on its annotated genome and biochemical information...
December 1, 2016: Journal of Industrial Microbiology & Biotechnology
https://www.readbyqxmd.com/read/27909823/gelatin-microspheres-containing-calcitonin-gene-related-peptide-or-substance-p-repair-bone-defects-in-osteoporotic-rabbits
#20
Jianghao Chen, Wei Liu, Jinxiu Zhao, Cong Sun, Jie Chen, Kaijin Hu, Linlin Zhang, Yuxiang Ding
OBJECTIVES: To investigate the therapeutic effect of gelatin microspheres containing different concentrations of calcitonin gene-related peptide (CGRP) or substance P on repairing bone defects in a rabbit osteoporosis model. RESULTS: Gelatin microspheres containing different concentrations of CGRP or substance P promoted osteogenesis after 3 months in a rabbit osteoporotic bone defective model. From micro-computed tomography imaging results, 10 nM CGRP was optimal for increasing the trabecular number and decreasing the trabecular bone separation degree; similar effects were observed with the microspheres containing 1 µM substance P...
December 1, 2016: Biotechnology Letters
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