Inverted bell-curve-based ensemble of deep learning models for detection of COVID-19 from chest X-rays

Novel Coronavirus 2019 disease or COVID-19 is a viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The use of chest X-rays (CXRs) has become an important practice to assist in the diagnosis of COVID-19 as they can be used to detect the abnormalities developed in the infected patients’ lungs. With the fast spread of the disease, many researchers across the world are striving to use several deep learning-based systems to identify the COVID-19 from such CXR images. To this end, we propose an inverted bell-curve-based ensemble of deep learning models for the detection of COVID-19 from CXR images. We first use a selection of models pretrained on ImageNet dataset and use the concept of transfer learning to retrain them with CXR datasets. Then the trained models are combined with the proposed inverted bell curve weighted ensemble method, where the output of each classifier is assigned a weight, and the final prediction is done by performing a weighted average of those outputs. We evaluate the proposed method on two publicly available datasets: the COVID-19 Radiography Database and the IEEE COVID Chest X-ray Dataset. The accuracy, F1 score and the AUC ROC achieved by the proposed method are 99.66%, 99.75% and 99.99%, respectively, in the first dataset, and, 99.84%, 99.81% and 99.99%, respectively, in the other dataset. Experimental results ensure that the use of transfer learning-based models and their combination using the proposed ensemble method result in improved predictions of COVID-19 in CXRs.

The amphoteric cartilage surface tested in the pH Range from 2.0 to 9.0

Background: Phospholipids adsorbed to negatively-charged proteoglycan matrix form phospholipid (membrane), have negatively charged surface (-PO4-) and are hydrophilic. Strong adsorption and strong cohesion are necessary for phospholipids to provide a good lubricant. The surface energy of spherical lipid bilayers have "bell-curve" shaped has amphoteric character and lowest surface energy at a pH 7.4 ± 1 of the natural joint. Objectives: The amphoteric character of the natural surface of the articular cartilage was determined by measuring the surface energy of the model spherical bilayer lipid membrane. It was found that the friction (f) vs. pH 2.0 to 9.0 of the pair (cartilage/cartilage) has the amphoteric character by exposing "bell-curve" shaped with an isoelectric point (IEP). Methods: The friction coefficient (f) was measured with the sliding pin-on-disc tribotester the friction between two surfaces (cartilage/cartilage) pair. The method of interfacial tension measurements of the spherical lipid bilayer model vs the pH over the range 0.2 to 9.0 was used. Results: The dependence of friction coefficient between two cartilage surfaces on the pH over the range 2.0 to 9.0 is demonstrated by a “bell - curve” in Fig. 2(A). The surface energy of a model spherical bilayer lipid membrane vs. the pH has the character of a “bell - curve” with an (IEP) is shown in Fig. 2(B). Conclusion: The amphoteric effect on friction between the bovine cartilage/cartilage contacts has been found to be highly sensitive to the pH of an aqueous solution. In this paper we demonstrate experimentally that the pH sensitivity of cartilage to friction provides a novel concept in joint lubrication on charged surfaces. The change in friction was consistently related to the change of charge density of an amphoteric surface.

The correlation analysis of the daily Covid-19 new cases data series in Albania

We analyzed herein the new covid-19 daily positive cases recorded in Albania. We observed that the distribution of the daily new cases is non-stationary and usually has a power law behavior in the low incidence zone, and a bell curve for the remaining part of the incidence interval. We qualified this finding as the indicator intensive dynamics and as proof that up now, the heard immunity has not been reached. By parallelizing the preferential attachment mechanisms responsible for a power law distribution in the social graphs elsewhere, we explain the low daily incidence distribution as result of the imprudent gatherings of peoples. Additionally, the bell-shaped distribution observed for the high daily new cases is agued as outcome of the competition between illness advances and restriction measures. The distribution is acceptably smooth, meaning that the management has been accommodated appropriately. This behavior is observed also for two neighbor countries Greece and Italy respectively, but was not observed for Turkey, Serbia, and North Macedonia. Next, we used the multifractal analysis to conclude about the features related with heterogeneity of the data. We have identified the local presence self-organization behavior in some separate time intervals. Formally and empirically we have identified that the full set of the data contain two regimes finalized already, followed by a third one which started in July 2021.

Vitality, Racial Creativity, and Biopolitics

In a materialist vitalism that emerged, nerve force as a physical energy was assumed to give idiosyncratic shape to organisms, races, and species. Borrowing from evolutionary theory and biometrics, Oliver Wendell Holmes suggests in Elsie Venner that the vital force of the average members of a race or species will prevail, while hybrids at the edges of the vital bell curve will expire, a principle that applies as well to literature, which has its own vital curve. William Dean Howells promotes a naturalized realism of the healthy, national (white, middle-class) average. W. E. B. Du Bois and Pauline Hopkins take on the task of establishing the African American race as vigorous and empowered rather than enervated—and of eluding constraining racial definition by oscillating between biological and immaterial conceptions of racial force.

Principles of Kabir Wealth Curve

The authors developed a wealth curve (bell curve) that can predict a group of individual’s wealth based on the crossover interaction effect of the average intelligence quotient (one's ability to perform, comprehend and learn) and emotional awareness (emotional ability to recognize and make sense of emotions). To move towards the right on the X-axis of the Kabir wealth curve (e.g. accumulate more wealth), individuals have to improve emotional awareness and choose a professional career path that lands higher income. Similarly, those facing social injustice can accumulate more wealth by improving emotional awareness, which will help them navigate challenging environments.

Beyond education by ranking: Let's not return to 'normal'

The cancellation of public examinations in England during the coronavirus pandemic drew attention to a long-standing educational concern. Grading and ranking students, in various ways, has taken place for many years, but in summer 2020 this process was shared between teachers and, initially, an 'algorithm'. Maintaining standards and consistent grade distributions is a feature of the exam system in 'normal' times. This article considers why exam grades are (roughly) normally distributed, tracing origins of bell-curve thinking, to suggest that we should not be returning to this kind of 'normal'.

The Pandemic News Experience: Covid-19, News Consumption, Mental Health, and the Demand for Positive News

COJO for COVID Recovery is a UKRI/AHRC-funded rapid Covid-19 response research project that addresses the role that constructive journalism (COJO), particularly solution-focused journalism, can play in the pandemic recovery. The research set out in this report details the findings of the project’s initial in-depth interviews and survey with UK news audiences. Four key sets of findings regarding Covid-19 news consumption and experience emerge from this analysis. 1.The high interest in Covid-19 news was associated with the need to monitor and navigate the uncertain evolution of the pandemic as it affected audiences. 2.There was a clear fluctuation that followed “an inverse Bell curve” (up-down-up) pattern of Covid-19 news consumption which was in parallel with the severity of the pandemic and its associated lockdown restrictions. 3.Many of our participants reported switching off from the news or avoiding it for reasons linked to mental and emotional health, including negativity, repetitive reporting and information overload. 4.Participants demanded the media provide more positive news that helps to lift the mood of the public and/or offers ways out of the pandemic.

Falling Short: Adverse Events Related to Patient Height

Measuring a patient’s height is a routine part of a healthcare encounter. But once completed, how often is this information used? For most of us who fall within 95% of the mean population height, this metric is rarely discussed, but what happens when it is overlooked? And what about those on the outer tails of the bell curve of population distribution? Almost 1 million (909,222) adults in the United States are at least 6'4", more than the entire population of South Dakota (884,659). Conversely, an estimated 30,000 Americans have a form of dwarfism, typically defined as an adult height no taller than 4'10". However, despite this prevalence, the healthcare system struggles to provide consistent, adequate care for patients with extreme heights. “Being tall is not a disease, but it is a consideration,” shared one 6' 3" woman, who descended from a long line of “Scottish Vikings.”* “I am one of the short ones at family reunions,” she continued; her father tops 6' 8". Experiences like hers prompted this investigation into the medical mishaps and trauma that have befallen those who are not “average-sized.”

Exploring How White-Faced Sakis Control Digital Visual Enrichment Systems

Computer-enabled screen systems containing visual elements have long been employed with captive primates for assessing preference, reactions and for husbandry reasons. These screen systems typically play visual enrichment to primates without them choosing to trigger the system and without their consent. Yet, what videos primates, especially monkeys, would prefer to watch of their own volition and how to design computers and methods that allow choice is an open question. In this study, we designed and tested, over several weeks, an enrichment system that facilitates white-faced saki monkeys to trigger different visual stimuli in their regular zoo habitat while automatically logging and recording their interaction. By analysing this data, we show that the sakis triggered underwater and worm videos over the forest, abstract art, and animal videos, and a control condition of no-stimuli. We also note that the sakis used the device significantly less when playing animal videos compared to other conditions. Yet, plotting the data over time revealed an engagement bell curve suggesting confounding factors of novelty and habituation. As such, it is unknown if the stimuli or device usage curve caused the changes in the sakis interactions over time. Looking at the sakis’ behaviours and working with zoo personnel, we noted that the stimuli conditions resulted in significantly decreasing the sakis’ scratching behaviour. For the research community, this study builds on methods that allow animals to control computers in a zoo environment highlighting problems in quantifying animal interactions with computer devices.