An Innovative Method for Automatic Grading of Retinal Blood Vessel Tortuosity

Abstract: The curvity is among the first alterations in the retinal vessel network to appear in many retinopathies , such as those due to hypertension. An automatic evaluation of retinal vessel tortuosity would help the early detection of such retinopathies. Quite a few techniques for tortuosity measurement and classification have been proposed, but they do not always match the clinical concept of tortuosity. This justifies the need for a new definition, able to express in mathematical terms the tortuosity as perceived by ophthalmologists. We propose here a new algorithm for the evaluation of tortuosity in vessels recognized in digital fundus images. It is based on partitioning each vessel in segments of constant sign curvature and then combining together each evaluation of such segments and their number. The algorithm has been compared with other available tortuosity measures on asset of 30 arteries and one of 30 veins from different images. These vessels had been preliminary ordered by a retinal specialist by increasing perceived tortuosity. The proposed algorithm proved to be the best one in matching the clinically perceived vessel tortuosity

Algorithms for Stable Matching and Clustering in a Grid

We study a discrete version of a geometric stable marriage problem originally proposed in a continuous setting by Hoffman, Holroyd, and Peres, in which points in the plane are stably matched to cluster centers, as prioritized by their distances, so that each cluster center is apportioned a set of points of equal area. We show that, for a discretization of the problem to an $n\times n$ grid of pixels with $k$ centers, the problem can be solved in time $O(n^2 \log^5 n)$, and we experiment with two slower but more practical algorithms and a hybrid method that switches from one of these algorithms to the other to gain greater efficiency than either algorithm alone. We also show how to combine geometric stable matchings with a $k$-means clustering algorithm, so as to provide a geometric political-districting algorithm that views distance in economic terms, and we experiment with weighted versions of stable $k$-means in order to improve the connectivity of the resulting clusters.Comment: 23 pages, 12 figures. To appear (without the appendices) at the 18th International Workshop on Combinatorial Image Analysis, June 19-21, 2017, Plovdiv, Bulgari

Efficacy of Fluoxetine, Riluzole and Amiloride in treating neuropathic pain associated with secondary progressive multiple sclerosis. Pre-specified analysis of the MS-SMART double-blind randomised placebo-controlled trial

BACKGROUND: Evidence-based treatment of pain in people with MS presents a major unmet need. OBJECTIVE: We aimed to establish if use of Fluoxetine, Riluzole or Amiloride improved neuropathic pain outcomes in comparison to placebo, in adults with secondary progressive MS participating in a trial of these putative neuroprotectants. METHODS: In pre-specified secondary analyses of the MS SMART phase-2b double-blind randomised controlled trial (NCT01910259), we analyzed reports of neuropathic pain, overall pain, and pain interference. Multivariate analyses included adjustment for baseline pain severity. Additionally, we explored associations of pain severity with clinical and MRI brain imaging variables. RESULTS: 445 Participants were recruited from 13 UK neuroscience centres. We found no statistically significant benefit of active intervention on any rating of neuropathic pain, or pain overall. Compared to placebo, adjusted mean difference in pain intensity was 0.38 (positive values favouring placebo, 95%CI -0.30 to 1.07, p = 0.27) for Amiloride; 0.52 (-0.17 to 1.22, p = 0.14) for Fluoxetine; and 0.40 (-0.30 to 1.10, p = 0.26) for Riluzole. Pain severity was positively correlated with depressive symptoms (Spearman correlation 0.19, 95%CI 0.10-0.28) and fatigue (Rho 0.30, 95%CI 0.20-0.39). CONCLUSION: Use of Fluoxetine, Riluzole or Amiloride was not associated with improvement in neuropathic pain symptoms, in comparison to placebo

Occupational Health and Safety Trainees Reflect on their Education and Future Careers During COVID-19.

Background: The National Institute for Occupational Safety and Health (NIOSH) funded Education and Research Centers (ERCs), located at 18 universities, with the mission to train occupational safety and health (OSH) leaders. The Florida Sunshine ERC has trained hundreds of students since its inception in 1997 through seven programs that collaboratively foster interdisciplinary education and applied research and practice. The COVID-19 pandemic has presented practical challenges for educators, students, and trainees, forcing institutions to move to remote learning. The pandemic also magnifies the importance of public health and OSH. Purpose: This evaluation elicited feedback from ERC trainees early in the pandemic (2020) and again in 2021 on how the pandemic affected their training, professional development, career plans, and wellbeing. Methods: Open-ended surveys were collected and focus groups were held with currently enrolled trainees from seven Sunshine ERC programs. Descriptive statistics were calculated, and qualitative transcripts were analyzed using MAXQDA software. Results: Through survey responses (45 respondents) and focus group discussions (9 participants), ERC trainees shared their perspectives on pandemic impacts in their performance and wellbeing, transition to remote learning, their respective OSH fields, and career plans during the pandemic. Programs should consider enhancing OSH curricula to respond to training needs and issues related to occupational stress and well-being, pragmatism and disaster response, and even more interdisciplinary training to prepare for emerging population-wide threats. Conclusions: OSH training will require shifts in teaching modalities and content to prepare OSH professionals for the future. Evaluation results informed teaching and training modifications to ensure that ERC objectives continue to be met and that trainees are well-prepared and supported

Deleterious Effects of Cold Air Inhalation on Coronary Physiological Indices in Patients With Obstructive Coronary Artery Disease

Background Cold air inhalation during exercise increases cardiac mortality, but the pathophysiology is unclear. During cold and exercise, dual‐sensor intracoronary wires measured coronary microvascular resistance (MVR) and blood flow velocity (CBF), and cardiac magnetic resonance measured subendocardial perfusion. Methods and Results Forty‐two patients (62±9 years) undergoing cardiac catheterization, 32 with obstructive coronary stenoses and 10 without, performed either (1) 5 minutes of cold air inhalation (5°F) or (2) two 5‐minute supine‐cycling periods: 1 at room temperature and 1 during cold air inhalation (5°F) (randomized order). We compared rest and peak stress MVR, CBF, and subendocardial perfusion measurements. In patients with unobstructed coronary arteries (n=10), cold air inhalation at rest decreased MVR by 6% (P=0.41), increasing CBF by 20% (P<0.01). However, in patients with obstructive stenoses (n=10), cold air inhalation at rest increased MVR by 17% (P<0.01), reducing CBF by 3% (P=0.85). Consequently, in patients with obstructive stenoses undergoing the cardiac magnetic resonance protocol (n=10), cold air inhalation reduced subendocardial perfusion (P<0.05). Only patients with obstructive stenoses performed this protocol (n=12). Cycling at room temperature decreased MVR by 29% (P<0.001) and increased CBF by 61% (P<0.001). However, cold air inhalation during cycling blunted these adaptations in MVR (P=0.12) and CBF (P<0.05), an effect attributable to defective early diastolic CBF acceleration (P<0.05) and associated with greater ST‐segment depression (P<0.05). Conclusions In patients with obstructive coronary stenoses, cold air inhalation causes deleterious changes in MVR and CBF. These diminish or abolish the normal adaptations during exertion that ordinarily match myocardial blood supply to demand

Development of Thick Superhydrophilic TiO₂−ZrO₂ Transparent Coatings Realized through the Inclusion of Poly(methyl methacrylate) and Pluronic-F127

A thick coating of hierarchically porous double templated TiO₂-ZrO₂-PMMA-PF127 with excellent self-cleaning properties and high transmittance has been developed for the first time on glass substrates using dip coating technique. Comparative studies of this sample with a thick and transparent coating of single templated TiO₂-ZrO₂-PMMA have been performed to probe the origin of its exceptional properties. The formation of the composites and successful incorporation of the polymer into the matrix have been verified by means of Fourier transform infrared (FTIR) spectroscopy. The porous nature of the film is studied using field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), small and wide angle X-ray scattering (SAXS-WAXS) measurements and high resolution transmission electron microscopy (HRTEM). Elemental mapping is used to reveal the presence and the pattern of distribution of constituent elements while Raman imaging is used to fathom the structure of nanopores on the surface of the film. The X-ray photoelectron spectroscopy (XPS) is used to detect the presence of Ti²⁺ and thereby verify the chemisorption of water on the surface of the film. The variation in the self-cleaning properties of the samples on UV-illumination has also been studied. The double templated film is found to possess the capability of hydrophilic retention even a day after UV-irradiation

A survey of performance enhancement of transmission control protocol (TCP) in wireless ad hoc networks

This Article is provided by the Brunel Open Access Publishing Fund - Copyright @ 2011 Springer OpenTransmission control protocol (TCP), which provides reliable end-to-end data delivery, performs well in traditional wired network environments, while in wireless ad hoc networks, it does not perform well. Compared to wired networks, wireless ad hoc networks have some specific characteristics such as node mobility and a shared medium. Owing to these specific characteristics of wireless ad hoc networks, TCP faces particular problems with, for example, route failure, channel contention and high bit error rates. These factors are responsible for the performance degradation of TCP in wireless ad hoc networks. The research community has produced a wide range of proposals to improve the performance of TCP in wireless ad hoc networks. This article presents a survey of these proposals (approaches). A classification of TCP improvement proposals for wireless ad hoc networks is presented, which makes it easy to compare the proposals falling under the same category. Tables which summarize the approaches for quick overview are provided. Possible directions for further improvements in this area are suggested in the conclusions. The aim of the article is to enable the reader to quickly acquire an overview of the state of TCP in wireless ad hoc networks.This study is partly funded by Kohat University of Science & Technology (KUST), Pakistan, and the Higher Education Commission, Pakistan

Perinatal outcomes in a South Asian setting with high rates of low birth weight

<p>Abstract</p> <p>Background</p> <p>It is unclear whether the high rates of low birth weight in South Asia are due to poor fetal growth or short pregnancy duration. Also, it is not known whether the traditional focus on preventing low birth weight has been successful. We addressed these and related issues by studying births in Kaniyambadi, South India, with births from Nova Scotia, Canada serving as a reference.</p> <p>Methods</p> <p>Population-based data for 1986 to 2005 were obtained from the birth database of the Community Health and Development program in Kaniyambadi and from the Nova Scotia Atlee Perinatal Database. Menstrual dates were used to obtain comparable information on gestational age. Small-for-gestational age (SGA) live births were identified using both a recent Canadian and an older Indian fetal growth standard.</p> <p>Results</p> <p>The low birth weight and preterm birth rates were 17.0% versus 5.5% and 12.3% versus 6.9% in Kaniyambadi and Nova Scotia, respectively. SGA rates were 46.9% in Kaniyambadi and 7.5% in Nova Scotia when the Canadian fetal growth standard was used to define SGA and 6.7% in Kaniyambadi and < 1% in Nova Scotia when the Indian standard was used. In Kaniyambadi, low birth weight, preterm birth and perinatal mortality rates did not decrease between 1990 and 2005. SGA rates in Kaniyambadi declined significantly when SGA was based on the Indian standard but not when it was based on the Canadian standard. Maternal mortality rates fell by 85% (95% confidence interval 57% to 95%) in Kaniyambadi between 1986–90 and 2001–05. Perinatal mortality rates were 11.7 and 2.6 per 1,000 total births and cesarean delivery rates were 6.0% and 20.9% among live births ≥ 2,500 g in Kaniyambadi and Nova Scotia, respectively.</p> <p>Conclusion</p> <p>High rates of fetal growth restriction and relatively high rates of preterm birth are responsible for the high rates of low birth weight in South Asia. Increased emphasis is required on health services that address the morbidity and mortality in all birth weight categories.</p

Cholesterol Homeostasis in Two Commonly Used Human Prostate Cancer Cell-Lines, LNCaP and PC-3

BACKGROUND:Recently, there has been renewed interest in the link between cholesterol and prostate cancer. It has been previously reported that in vitro, prostate cancer cells lack sterol-mediated feedback regulation of the major transcription factor in cholesterol homeostasis, sterol-regulatory element binding protein 2 (SREBP-2). This could explain the accumulation of cholesterol observed in clinical prostate cancers. Consequently, perturbed feedback regulation to increased sterol levels has become a pervasive concept in the prostate cancer setting. Here, we aimed to explore this in greater depth. METHODOLOGY/PRINCIPAL FINDINGS:After altering the cellular cholesterol status in LNCaP and PC-3 prostate cancer cells, we examined SREBP-2 processing, downstream effects on promoter activity and expression of SREBP-2 target genes, and functional activity (low-density lipoprotein uptake, cholesterol synthesis). In doing so, we observed that LNCaP and PC-3 cells were sensitive to increased sterol levels. In contrast, lowering cholesterol levels via statin treatment generated a greater response in LNCaP cells than PC-3 cells. This highlighted an important difference between these cell-lines: basal SREBP-2 activity appeared to be higher in PC-3 cells, reducing sensitivity to decreased cholesterol levels. CONCLUSION/SIGNIFICANCE:Thus, prostate cancer cells are sensitive to changing sterol levels in vitro, but the extent of this regulation differs between prostate cancer cell-lines. These results shed new light on the regulation of cholesterol metabolism in two commonly used prostate cancer cell-lines, and emphasize the importance of establishing whether or not cholesterol homeostasis is perturbed in prostate cancer in vivo