No-reference image quality assessment through the von Mises distribution

An innovative way of calculating the von Mises distribution (VMD) of image entropy is introduced in this paper. The VMD's concentration parameter and some fitness parameter that will be later defined, have been analyzed in the experimental part for determining their suitability as a image quality assessment measure in some particular distortions such as Gaussian blur or additive Gaussian noise. To achieve such measure, the local R\'{e}nyi entropy is calculated in four equally spaced orientations and used to determine the parameters of the von Mises distribution of the image entropy. Considering contextual images, experimental results after applying this model show that the best-in-focus noise-free images are associated with the highest values for the von Mises distribution concentration parameter and the highest approximation of image data to the von Mises distribution model. Our defined von Misses fitness parameter experimentally appears also as a suitable no-reference image quality assessment indicator for no-contextual images.Comment: 29 pages, 11 figure

High-performance fiber reinforced concrete coupling beams: from research to practice

Results from experimental research that led to the development of a new design of coupling beams constructed with High-Performance Fiber Reinforced Concrete (HPFRC) and simplified reinforcement detailing are presented, along with information related to its implementation in a high-rise building in the city of Seattle, WA. The experimental program consisted of the testing, under large displacement reversals, of a series of large-scale HPFRC coupling beams with span-toheight ratios ranging between 1.75 and 3.3. The main goal of the experimental program was to evaluate the possibility of simplifying diagonal and confinement reinforcement detailing without compromising seismic performance. Experimental results indicate that the use of HPFRC allows the complete elimination of diagonal reinforcement in beams with span-to-height ratios greater than or equal to approximately 2.2. Also, special confinement reinforcement, as used in regular reinforced concrete coupling beams, was found to only be required over a distance of half the beam height from each beam end. For beams with span-to-height ratios smaller than approximately 2.2, a 2/3 reduction in diagonal reinforcement was found to be possible, with the same relaxation in confinement reinforcement as for the more slender coupling beams. Drift capacities of the HPFRC coupling beam specimens, when subjected to shear reversals with amplitudes comparable to the upper shear limit allowed in the ACI Building Code, ranged between approximately 5% and 7% for span-to-height ratios of 1.75 and 3.3, respectively

Percutaneous stereotactic en bloc excision of nonpalpable breast carcinoma: a step in the direction of supraconservative surgery

peer reviewedRecently, the advanced breast biopsy instrumentation (ABBI) system has been introduced as an alternative to conventional breast biopsy techniques. This study was prospectively conducted to evaluate the potential of the ABBI method in locoregional management of a consecutive series of patients with nonpalpable mammographically detected breast carcinomas. Sixty-one consecutive patients underwent an ABBI procedure as a first step before possible surgery for nonpalpable breast lesions that would in any case require complete excision. For the 27 patients in whom the ABBI biopsy revealed malignancy further surgery was recommended, including re-excision of the biopsy site and axillary dissection in cases of infiltrating carcinoma. We calculated the probabilities that the ABBI specimen would have tumor-free margins and that a definitely complete excision had been achieved as a function of the mammographic or pathological diameter of the cancer. For cancer with a pathological diameter less than 10 mm, measured on the ABBI specimen, the probability (92%) of obtaining complete resection was significantly better than for larger lesions (P = 0.01, Fisher's exact test). Although the therapeutic perspectives for the ABBI method are limited at present, we suggest that this approach is a first step in the direction of a surgical strategy that is better adapted to the pathological characteristics peculiar to these small tumors, whose incidence is increasing. (C) 2002 Elsevier Science Ltd. All rights reserved

Update of Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias (International Endohernia Society (IEHS)) : Part B

In 2014 the International Endohernia Society (IEHS) published the first international "Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias". Guidelines reflect the currently best available evidence in diagnostics and therapy and give recommendations to help surgeons to standardize their techniques and to improve their results. However, science is a dynamic field which is continuously developing. Therefore, guidelines require regular updates to keep pace with the evolving literature. Methods For the development of the original guidelines all relevant literature published up to year 2012 was analyzed using the ranking of the Oxford Centre for Evidence-Based-Medicine. For the present update all of the previous authors were asked to evaluate the literature published during the recent years from 2012 to 2017 and revise their statements and recommendations given in the initial guidelines accordingly. In two Consensus Conferences (October 2017 Beijing, March 2018 Cologne) the updates were presented, discussed, and confirmed. To avoid redundancy, only new statements or recommendations are included in this paper. Therefore, for full understanding both of the guidelines, the original and the current, must be read. In addition, the new developments in repair of abdominal wall hernias like surgical techniques within the abdominal wall, release operations (transversus muscle release, component separation), Botox application, and robot-assisted repair methods were included. Results Due to an increase of the number of patients and further development of surgical techniques, repair of primary and secondary abdominal wall hernias attracts increasing interests of many surgeons. Whereas up to three decades ago hernia-related publications did not exceed 20 per year, currently this number is about 10-fold higher. Recent years are characterized by the advent of new techniques-minimal invasive techniques using robotics and laparoscopy, totally extraperitoneal repairs, novel myofascial release techniques for optimal closure of large defects, and Botox for relaxing the abdominal wall. Furthermore, a concomitant rectus diastasis was recognized as a significant risk factor for recurrence. Despite still insufficient evidence with respect to these new techniques it seemed to us necessary to include them in the update to stimulate surgeons to do research in these fields. Conclusion Guidelines are recommendations based on best available evidence intended to help the surgeon to improve the quality of his daily work. However, science is a continuously evolving process, and as such guidelines should be updated about every 3 years. For a comprehensive reference, however, it is suggested to read both the initially guidelines published in 2014 together with the update. Moreover, the presented update includes also techniques which were not known 3 years before

A Quality of Recognition Case Study: Texture-based Segmentation and MRI Quality Assessment

Muscle texture may be used as a descriptive feature for the segmentation of skeletal muscle in Magnetic Resonance Images (MRI). However, MRI acquisition is not always ideal and the texture richness might become compromised. Moreover, the research for the development of texture quality metrics, and particularly no-reference metrics, to be applied to the specific context of MRI is still in a very early stage. In this paper, a case study is established from a texture-based segmentation approach for skeletal muscle, which was tested in a thigh Dixon MRI database. Upon the obtained performance measures, the relation between objective image quality and the texture MRI richness is explored, considering a set of state-of-the-art no-reference image quality metrics. A discussion on the effectiveness of existing quality assessment methods in measuring MRI texture quality is carried out, based on Pearson and Spearman correlation outcomes.info:eu-repo/semantics/publishedVersio

The response of early neural genes to FGF signaling or inhibition of BMP indicate the absence of a conserved neural induction module

<p>Abstract</p> <p>Background</p> <p>The molecular mechanism that initiates the formation of the vertebrate central nervous system has long been debated. Studies in <it>Xenopus </it>and mouse demonstrate that inhibition of BMP signaling is sufficient to induce neural tissue in explants or ES cells respectively, whereas studies in chick argue that instructive FGF signaling is also required for the expression of neural genes. Although additional signals may be involved in neural induction and patterning, here we focus on the roles of BMP inhibition and FGF8a.</p> <p>Results</p> <p>To address the question of necessity and sufficiency of BMP inhibition and FGF signaling, we compared the temporal expression of the five earliest genes expressed in the neuroectoderm and determined their requirements for induction at the onset of neural plate formation in <it>Xenopus</it>. Our results demonstrate that the onset and peak of expression of the genes vary and that they have different regulatory requirements and are therefore unlikely to share a conserved neural induction regulatory module. Even though all require inhibition of BMP for expression, some also require FGF signaling; expression of the early-onset pan-neural genes <it>sox2 </it>and <it>foxd5α </it>requires FGF signaling while other early genes, <it>sox3</it>, <it>geminin </it>and <it>zicr1 </it>are induced by BMP inhibition alone.</p> <p>Conclusions</p> <p>We demonstrate that BMP inhibition and FGF signaling induce neural genes independently of each other. Together our data indicate that although the spatiotemporal expression patterns of early neural genes are similar, the mechanisms involved in their expression are distinct and there are different signaling requirements for the expression of each gene.</p