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Metrics of mechanical chest compression device use in out‐of‐hospital cardiac arrest

ObjectiveThe quality of cardiopulmonary resuscitation (CPR) affects outcomes from cardiac arrest, yet manual CPR is difficult to administer. Although mechanical CPR (mCPR) devices offer high quality CPR, only limited data describe their deployment, their interaction with standard manual CPR (sCPR), and the consequent effects on chest compression continuity and patient outcomes. We sought to descri

The Study Protocol for the LINC (LUCAS in Cardiac Arrest) Study : A study comparing conventional adult out-of-hospital cardiopulmonary resuscitation with a concept with mechanical chest compressions and simultaneous defibrillation

Background: The LUCAS™ device delivers mechanical chest compressions that have been shown in experimental studies to improve perfusion pressures to the brain and heart as well as augmenting cerebral blood flow and end tidal CO2, compared with results from standard manual cardiopulmonary resuscitation (CPR). Two randomised pilot studies in out-of-hospital cardiac arrest patients have not shown impr

Additive clinical impact of epidermal growth factor receptor and podocalyxin-like protein expression in pancreatic and periampullary adenocarcinomas

The outcome of periampullary adenocarcinomas remains poor with few treatment options. Podocalyxin-like protein (PODXL) is an anti-adhesive protein, the high expression of which has been shown to confer a poor prognosis in numerous malignancies. A correlation and adverse prognostic synergy between PODXL and the epidermal growth factor receptor (EGFR) has been observed in colorectal cancer. Here, we

Influence of alternating V-rows tube layout on thermal-hydraulic characteristics of twisted elliptical tube heat exchangers

An innovative alternating V-rows triangular tube layout was devised for the twisted elliptical tube heat exchangers to enhance heat transfer between adjacent tubes. Under the same tube circumference, altogether eleven twisted elliptical tube heat exchangers with two tube layouts, diverse aspect ratios of twisted elliptical tubes and different twisted pitches were constructed and simulated, includi

Electron channelling : challenges and opportunities for compositional analysis of nanowires by TEM

Energy dispersive x-ray spectroscopy in a transmission electron microscope is often the first method employed to characterize the composition of nanowires. Ideally, it should be accurate and sensitive down to fractions of an atomic percent, and quantification results are often reported as such. However, one can often get substantial errors in accuracy even though the precision is high: for nanowir

Gridded parasitic patch stacked microstrip array antenna for 60 GHz band

An array antenna design based on a gridded parasitic patch stacked microstrip antenna element is presented. The radiating part in the top layer of one antenna element has nine rectangular metal patches placed in a grid with three rows and three columns with a separation of 0.1 mm between the patches. Two means of realising the array are investigated. In a regular 2 × 2 concept, the parasitic patch

Grand canonical simulations of ions between charged conducting surfaces using exact 3D Ewald summations

We present a useful methodology to simulate ionic fluids confined by two charged and perfectly conducting surfaces. Electrostatic interactions are treated using a modified 3D Ewald sum, which accounts for all image charges across the conductors, as well as the 2D periodicity, parallel to the surfaces. The energy expression is exact, and the method is trivial to implement in existing Ewald codes. W

Asymptotic number of Z3Δ cells covering C(1) surface on uniform grid and complexity of recursive-partitioning simulation of septal tissue regions

The exact asymptotic computational complexity for a problem of indexing cells on a uniform grid intersecting with a union of C(1) surfaces has been proven. The computational complexity of the recursive partition indexing algorithm, utilized for simulation of septated tissues, is derived and the algorithm is demonstrated as being asymptotically optimal.

Estimation of scattered radiation in digital breast tomosynthesis

Digital breast tomosynthesis (DBT) is a promising technique to overcome the tissue superposition limitations found in planar 2D x-ray mammography. However, as most DBT systems do not employ an anti-scatter grid, the levels of scattered radiation recorded within the image receptor are significantly higher than that observed in planar 2D x-ray mammography. Knowledge of this field is necessary as par

A statistically defined anthropomorphic software breast phantom

Purpose: Digital anthropomorphic breast phantoms have emerged in the past decade because of recent advances in 3D breast x-ray imaging techniques. Computer phantoms in the literature have incorporated power-law noise to represent glandular tissue and branching structures to represent linear components such as ducts. When power-law noise is added to those phantoms in one piece, the simulated fibrog

Analysis of parenchymal texture with digital breast tomosynthesis : Comparison with digital mammography and implications for cancer risk assessment

Purpose:To correlate the parenchymal texture features at digital breast tomosynthesis(DBT)and digital mammography with breast percent density(PD), an established breast cancer risk factor, in a screening population of women. Materials and Methods: This HIPAA-compliant study was approved by the institutional review board. Bilateral DBT images and digital mammograms from 71 women (mean age, 54 years

Development of a physical 3D anthropomorphic breast phantom

Purpose: Develop a technique to fabricate a 3D anthropomorphic breast phantom with known ground truth for image quality assessment of 2D and 3D breast x-ray imaging systems. Methods: The phantom design is based on an existing computer model that can generate breast voxel phantoms of varying composition, size, and shape. The physical phantom is produced in two steps. First, the portion of the voxel

Breast percent density : Estimation on digital mammograms and central tomosynthesis projections

Purpose: To evaluate inter- and intrareader agreement in breast percent density (PD) estimation on clinical digital mammograms and central digital breast tomosynthesis (DBT) projection images. Materials and Methods: This HIPAA-compliant study had institutional review board approval; all patients provided informed consent. Breast PD estimation was performed on the basis of anonymized digital mammog

Mammogram registration : A phantom-based evaluation of compressed breast thickness variation effects

The temporal comparison of mammograms is complex; a wide variety of factors can cause changes in image appearance. Mammogram registration is proposed as a method to reduce the effects of these changes and potentially to emphasize genuine alterations in breast tissue. Evaluation of such registration techniques is difficult since ground truth regarding breast deformations is not available in clinica

Calculation of the properties of digital mammograms using a computer simulation

A Mote Carlo computer model of mammography has been developed to study and optimise the performance of digital mammographic systems. The program uses high-resolution voxel phantoms to model the breast, which simulate the adipose and fibroglandular tissues, Cooper's ligaments, ducts and skin in three dimensions. The model calculates the dose to each tissue, and also the quantities such as energy im

Breast dosimetry using high-resolution voxel phantoms

A computer model of X-ray mammography has been developed, which uses quasi-realistic high-resolution voxel phantoms to simulate the breast. The phantoms have 400 μm voxels and simulate the three-dimensional distributions of adipose and fibroglandular tissues, Cooper's ligaments, ducts and skin and allow the estimation of dose to individual tissues. Calculations of the incident air kerma to mean gl

Classification of galactograms with ramification matrices : Preliminary results

Rationale and Objectives. The poor specificity of galactography, the imaging modality generally indicated in cases of nipple discharge, has led to a large number of biopsies with negative results. A quantitative scheme for classifying galactographic findings might help reduce the number of such biopsies in the future. As a first step toward that goal, the authors have studied one quantitative meth

Non-rigid registration of mammograms obtained with variable breast compression : A phantom study

The amount of breast compression applied during a mammographic exam affects the appearance of mammograms by introducing variations in the shape, position, and contrast of breast anatomical structures, which can conceal existing breast abnormalities or generate false alarms. Due to the complex tissue organization and elastic properties of the breast and the projective nature of mammography, rigid r

Aliasing effects in digital images of line-pair phantoms

Line-pair phantoms are commonly used for evaluating screen-film systems. When imaged digitally, aliasing effects give rise to additional periodic patterns. This paper examines one such effect that medical physicists are likely to encounter, and which can be used as an indicator of super-resolution.

CNN paradigm based multilevel halftoning of digital images

-An algorithm for displaying gray level images using a small number of flxed quantization levels is proposed. The algorithm, called multilevel halftoning, is based on the Cellular Neural Networks (CNN) paradigm. It tracks the CNN transient outputs and selects the image which is subjectively perceived to be the best when reduced to the allowed number of gray levels. The selection criterion is based