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Design of Full-Scale Endwall Film Cooling of a Turbine Vane
Endwall film cooling is a significant cooling method to protect the endwall region and the junction region of endwall and a turbine vane, where usually a relatively high temperature load exists. This work aims to find the optimized arrangement of film cooling holes on the endwall and improve the film cooling in some difficult regions on the endwall, such as pressure side-endwall junction region. S
Sexual and functional long-term outcomes following advanced pelvic cancer and reconstruction using vertical rectus abdominis myocutaneous and gluteal myocutaneous flap
Introduction: After extensive pelvic surgery for cancer two flap types are used at Skåne University Hospital (SUS), Sweden for perineal reconstruction: vertical rectus abdominis myocutaneous flap and gluteal flap with or without vaginal reconstruction. The objective was to study the long-term outcomes in patients treated for advanced pelvic cancer receiving a flap. Method: Patients with pelvic can
A commentary on “The trouble with trust : Time-series analysis of social capital, income inequality, and COVID-19 deaths in 84 countries”
This study investigates associations between central aspects of social capital (social trust, group affiliations, civic engagement, confidence in state institutions), income inequality (Gini index for income), and COVID-19 mortality in 84 countries included in different time waves of the World Values Survey (WVS) (Elgar et al., 2020). Comments: First, infectious diseases are either patterned accor
Clinical relevance of positive patch test reactions to lanolin : A ROAT study
Background: Lanolin is often included when patch testing for common contact allergens. The clinical relevance of a positive patch test reaction to lanolin markers is, however, still a subject for debate. Objectives: To evaluate Amerchol L101 as a marker of lanolin allergy and investigate the clinical impact of lanolin-containing moisturizers on healthy and damaged skin using the repeated open appl
3d phase-contrast nanotomography of unstained human skin biopsies may identify morphological differences in the dermis and epidermis between subjects
Background: Enteric neuropathy is described in most patients with gastrointestinal dysmotility and may be found together with reduced intraepidermal nerve fiber density (IENFD). The aim of this pilot study was to assess whether three-dimensional (3d) imaging of skin biopsies could be used to examine various tissue components in patients with gastrointestinal dysmotility. Material and methods: Four
Brand orientation in action – A transformational learning intervention
This article provides in-depth insight into the dynamics of a transformation from market orientation to brand orientation. By including a wide range of stakeholders in an action research intervention, a detailed description is provided regarding the transformation of a large Swedish public primary care organization during a turbulent marketization process. Brand management theory and practice are
Khalkha Mongolian
This chapter gives an introduction to the basic structures of Khalkha Mongolian, most of which are similar to those of Mongolian proper in general. Segmental phonology (vowels and consonants) and word structure are analyzed. Major changes from earlier stages of the language are described briefly, as is the writing system, based on the Cyrillic alphabet. Vowel harmony, based on pharyngeality (ATR)
The Path of Life – for the Wise Only? : On Psalm 16 and How to Avoid Sheol Below
Spatially localized sparse representations for breast lesion characterization
Rationale: The topic of sparse representation of samples in high dimensional spaces has attracted growing interest during the past decade. In this work, we develop sparse representation-based methods for classification of radiological imaging patterns of breast lesions into benign and malignant states. Methods: We propose a spatial block decomposition method to address irregularities of the approx
Technical Note: Noise models for virtual clinical trials of digital breast tomosynthesis
Purpose: To investigate the use of an affine-variance noise model, with correlated quantum noise and spatially dependent quantum gain, for the simulation of noise in virtual clinical trials (VCT) of digital breast tomosynthesis (DBT).Methods: Two distinct technologies were considered: an amorphous-selenium (a-Se) detector with direct conversion and a thallium-doped cesium iodide (CsI(Tl)) detector
Evaluation of non-Gaussian statistical properties in virtual breast phantoms
Images derived from a "virtual phantom" can be useful in characterizing the performance of imaging systems. This has driven the development of virtual breast phantoms implemented in simulation environments. In breast imaging, several such phantoms have been proposed. We analyze the non-Gaussian statistical properties from three classes of virtual breast phantoms and compare them to similar statist
Restoration of low-dose digital breast tomosynthesis
In breast cancer screening, the radiation dose must be kept to the minimum necessary to achieve the desired diagnostic objective, thus minimizing risks associated with cancer induction. However, decreasing the radiation dose also degrades the image quality. In this work we restore digital breast tomosynthesis (DBT) projections acquired at low radiation doses with the goal of achieving a quality co
Modeling the mechanical behavior of the breast tissues under compression in real time
This work presents a data-driven model to simulate the mechanical behavior of the breast tissues in real time. The aim of this model is to speed up some multimodal registration algorithms, as well as some image-guided interventions. Ten virtual breast phantoms were used in this work. Their deformation during a mammography was performed off-line using the finite element method. Three machine learni
Method for Simulating Dose Reduction in Digital Breast Tomosynthesis
This paper proposes a new method of simulating dose reduction in digital breast tomosynthesis, starting from a clinical image acquired with a standard radiation dose. It considers both signal-dependent quantum and signal-independent electronic noise. Furthermore, the method accounts for pixel crosstalk, which causes the noise to be frequency-dependent, thus increasing the simulation accuracy. For
Method for simulating dose reduction in digital mammography using the Anscombe transformation
Purpose: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. Methods: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such
Description and Characterization of a Novel Method for Partial Volume Simulation in Software Breast Phantoms
A modification to our previous simulation of breast anatomy is proposed to improve the quality of simulated x-ray projections images. The image quality is affected by the voxel size of the simulation. Large voxels can cause notable spatial quantization artifacts; small voxels extend the generation time and increase the memory requirements. An improvement in image quality is achievable without redu
Methodology based on genetic heuristics for in-vivo characterizing the patient-specific biomechanical behavior of the breast tissues
This paper presents a novel methodology to in-vivo estimate the elastic constants of a constitutive model proposed to characterize the mechanical behavior of the breast tissues. An iterative search algorithm based on genetic heuristics was constructed to in-vivo estimate these parameters using only medical images, thus avoiding invasive measurements of the mechanical response of the breast tissues
Evaluating the sensitivity of the optimization of acquisition geometry to the choice of reconstruction algorithm in digital breast tomosynthesis through a simulation study
Due to the limited number of views and limited angular span in digital breast tomosynthesis (DBT), the acquisition geometry design is an important factor that affects the image quality. Therefore, intensive studies have been conducted regarding the optimization of the acquisition geometry. However, different reconstruction algorithms were used in most of the reported studies. Because each type of
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.