bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of an HTLV/HIV dual infection model with diffusion
Authors: Elaiw A. M. ,   Department of Mathematics, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia, AlShamrani N. H. ,   Department of Mathematics, Faculty of Science, Al-Azhar University, Assiut Branch, Assiut 71452, Egypt,   Department of Mathematics, Faculty of Science, University of Jeddah, P.O. Box 80327, Jeddah 21589, Saudi Arabia
Published: October 2021

In the literature, several HTLV-I and HIV single infections models with spatial dependence have been developed and analyzed. However, modeling HTLV/HIV dual infection with diffusion has not been studied. In this work we derive and investigate a PDE model that describes the dynamics of HTLV/HIV dual infection taking into account the mobility of viruses and cells. The model includes the effect of Cytotoxic T lymphocytes (CTLs) immunity. Although HTLV-I and HIV primarily target the same host, CD$ 4^{+} $T cells, via infected-to-cell (ITC) contact, however the HIV can also be transmitted through free-to-cell (FTC) contact. Moreover, HTLV-I has a vertical transmission through mitosis of active HTLV-infected cells. The well-posedness of solutions, including the existence of global solutions and the boundedness, is justified. We derive eight threshold parameters which govern the existence and stability of the eight steady states of the model. We study the global stability of all steady states based on the construction of suitable Lyapunov functions and usage of Lyapunov-LaSalle asymptotic stability theorem. Lastly, numerical simulations are carried out in order to verify the validity of our theoretical results.
Regime‐dependent effects of uncertainty shocks: A structural interpretation
Authors: Lhuissier Stéphane , Tripier Fabien
Published: October 2021

Using a Markov‐switching VAR, we show that the effects of uncertainty shocks on output are four times higher in a regime of economic distress than in a tranquil regime. We then provide a structural interpretation of these facts. To do so, we develop a business cycle model in which agents are aware of the possibility of regime changes when forming expectations. The model is estimated using a Bayesian minimum distance estimator that minimizes, over the set of structural parameters, the distance between the regime‐switching VAR‐based impulse response functions and those implied by the model. Our results point to worsening credit‐market conditions that amplify shocks during distress periods. Finally, we show that the expectation effect of regime switching in financial conditions is an important component of the financial accelerator mechanism. If agents are more pessimistic about future financial conditions, then the output effects of shocks are amplified.
Do elite colleges matter? The impact on entrepreneurship decisions and career dynamics
Authors: Guo Naijia , Leung Charles Ka Yui
Published: October 2021

Elite college attendance significantly impacts students' entrepreneurship decisions and career dynamics. We find that an elite college degree is positively correlated with entrepreneurship (i.e., owning an incorporated business) but not with other self‐employment forms. Our overlapping generations model captures self‐selection in education and career choices based on heterogeneous ability and family wealth endowments over the life cycle. Our estimates show that (1) entrepreneurs and other self‐employed individuals require different types of human capital, and (2) elite colleges generate considerably more human capital gain than ordinary colleges, particularly for entrepreneurs. Distinguishing between elite and ordinary colleges improves our prediction of entrepreneurship decisions. Providing subsidies for elite colleges is more efficient than subsidizing their ordinary counterparts to encourage entrepreneurship, enhance intergenerational mobility, and enhance welfare. In contrast, although start‐up subsidy increases entrepreneurship, it does not improve their performance, and it is inferior to education subsidy in generating efficiency, equality, and intergenerational mobility.
Panel experiments and dynamic causal effects: A finite population perspective
Authors: Bojinov Iavor , Rambachan Ashesh , Shephard Neil
Published: October 2021

In panel experiments, we randomly assign units to different interventions, measuring their outcomes, and repeating the procedure in several periods. Using the potential outcomes framework, we define finite population dynamic causal effects that capture the relative effectiveness of alternative treatment paths. For a rich class of dynamic causal effects, we provide a nonparametric estimator that is unbiased over the randomization distribution and derive its finite population limiting distribution as either the sample size or the duration of the experiment increases. We develop two methods for inference: a conservative test for weak null hypotheses and an exact randomization test for sharp null hypotheses. We further analyze the finite population probability limit of linear fixed effects estimators. These commonly‐used estimators do not recover a causally interpretable estimand if there are dynamic causal effects and serial correlation in the assignments, highlighting the value of our proposed estimator.
Fixed‐
k inference for volatility
Authors: Bollerslev Tim , Li Jia , Liao Zhipeng
Published: October 2021

We present a new theory for the conduct of nonparametric inference about the latent spot volatility of a semimartingale asset price process. In contrast to existing theories based on the asymptotic notion of an increasing number of observations in local estimation blocks, our theory treats the estimation block size
k as fixed. While the resulting spot volatility estimator is no longer consistent, the new theory permits the construction of asymptotically valid and easy‐to‐calculate pointwise confidence intervals for the volatility at any given point in time. Extending the theory to a high‐dimensional inference setting with a growing number of estimation blocks further permits the construction of uniform confidence bands for the volatility path. An empirically realistically calibrated simulation study underscores the practical reliability of the new inference procedures. An empirical application based on intraday data for the S&P 500 equity index reveals highly significant abrupt changes, or jumps, in the market volatility at FOMC news announcement times, validating recent uses of various high‐frequency‐based identification schemes in asset pricing finance and monetary economics.
Operare come archivista in un archivio della nobiltà romana nel Seicento
Authors: Baroncelli Orsetta
Published: October 2021

«Non perdere la memoria, chiama un archivista!». Questa freddura archivistica, facilmente applicabile anche ad archivisti di antico regime, contribuisce a mettere a fuoco, a suo modo, l’importanza di questa figura professionale, il cui ruolo nel processo di trasmissione della memoria è stato (ed è) troppo spesso misconosciuto. Il presente saggio – frutto di una ricerca svolta negli archivi della nobiltà romana del XVII secolo (famiglie Lante della Rovere, Orsini, Barberini, Colonna, Ruspoli, Marescotti, Caetani ecc.) – intende offrire un contributo alla ricostruzione prosopografica del personale degli archivi in età moderna, e più generale alla storia sociale dell’archivistica.
Effetti scenografici e macchine spettacolari nelle “performance” pubbliche nella Roma del primo Settecento
Authors: Blichmann Diana
Published: October 2021

A partire dal 1700 ca. erano in atto in Italia dei cambiamenti drammaturgici e scenografici iniziati dall’Accademia dell’Arcadia che avrebbero mutato gli sfarzosi effetti scenografici e le macchine spettacolari nei drammi per musica a favore di una più spiccata semplicità e verosimiglianza scenica, rivolta verso rappresentazioni teatrali “utili”. Nonostante ciò, durante diverse rappresentazioni teatrali nei teatri pubblici a Roma, la spettacolarità rimase fondamentale. Con la comparsa di divinità (Teatro Capranica) e personificazioni allegoriche (Teatro Alibert) “in machina”, gli architetti scenografi realizzavano nei punti cruciali del dramma una parte decisiva della performance. In questo studio ci si interroga sull’estetica degli effetti e delle macchine spettacolari all’interno delle performance attraverso libretti, manoscritti musicali, fonti archivistiche e iconografiche. Ci si chiede se gli eventi spettacolari, le divinità e personificazioni “in machina” siano stati dei media supplementari dello spettacolo oppure portatori autonomi di precisi messaggi. Attraverso la presenza delle macchine in due teatri diversi saranno analizzati due “modelli spettacolari”.
Eventi-spettacolo nella cerchia di André de Melo e Castro, ambasciatore portoghese a Roma (1718-1728)
Authors: Fernandes Cristina
Published: October 2021

Scopo del contributo è lo studio di una serie di «eventi-spettacolo» nella cerchia dell’ambasciatore del Portogallo presso la Santa Sede, André de Melo e Castro, durante il decennio 1718-1728. L’arco temporale considerato ci permette di esaminare le tracce lasciateci dalle performance nelle fonti d’archivio sia in una prospettiva sincronica, a partire da una serie di micro-eventi correlati tra loro, sia in una prospettiva diacronica, attraverso la successione di diversi eventi-spettacolo. L’analisi di queste tracce della performance (musicale, teatrale, coreografica) è la base per una riflessione sulla relazione tra gli spettacoli e la storia socio-politica, tenendo in considerazione somiglianze e differenze con le pratiche culturali dell’aristocrazia romana. Partendo da un quadro più ampio, particolare attenzione sarà data a quegli eventi-spettacolo (cantate, pastorali, commedie all’improvviso, balli ecc.) svoltisi presso il Palazzo Cesarini, residenza dell’aristocratico e diplomatico portoghese al servizio del re Giovanni V.
Relação das Dependências Física, Psicológica e Comportamental na Cessação do Tabagismo
Authors: Silveira Kallinca Merillen , Assumpção Francielle , Andrade André Luiz Monezi , De Micheli Denise , Lopes Fernanda Machado
Published: October 2021

O Programa de Cessação do Tabagismo (PCT) tem por objetivo a abstinência do cigarro por meio da intervenção com foco na dependência física, psicológica e comportamental. Este estudo investigou a relação entre os tipos de dependência, padrão de consumo, nível de fissura e motivação para a abstinência entre fumantes inscritos em um PCT. Inscreveram-se nos 11 grupos do PCT 179 fumantes (56,7% mulheres). Os participantes apresentaram uma média de 41 anos de idade e fumavam uma média de 19 cigarros por dia. O tempo médio de fumo dos participantes foi de 25 anos. Todos responderam instrumentos específicos para mensurar dependência física, psicológica e comportamental, nível de fissura e motivação para parar de fumar e participaram de uma entrevista individual em que forneceram a medida biológica do nível de monóxido de carbono. Os resultados indicaram correlação positiva entre diversas variáveis, com destaque para os três tipos de dependências entre si e com o número de cigarros fumados por dia, tempo de consumo e fissura; e entre duas medidas de dependência física (autorrelato e biológica). No início do comportamento de fumar, a dependência psicológica é mais intensa, e as demais se tornam mais intensas ao longo do tempo e intensidade do consumo.
Social Change
Authors: Drenner Karla L.
Published: October 2021

The differences between states and within states are profound, and while that has long been true, it is much more consequential to LGBT individuals since the legalization of same-sex marriage. Social change relating to LGBT issues were originally addressed in a 1997 article written by Thomas Stoddard titled “Bleeding Heart: Reflections on Using the Law to Make Social Change.” This chapter uses his framework and examines legislative responses to the legalization of same-sex marriage focusing on place.
Addressing Sexual and Gender Diversity in an English Education Teacher Preparation Program
Authors: Cramer Katherine Mason
Published: October 2021

Teacher education programs as a whole do little to prepare graduates to create and maintain classroom and school cultures that recognize and affirm lesbian, gay, bisexual, transgender, questioning/queer + (LGBTQ+) identities. This chapter describes how an English education program chair at a Midwestern university has integrated the study of sexual and gender diversity alongside English language arts pedagogy in three different courses, including specific texts and learning activities, as well as student responses to the in-class experiences. Recommendations for future study and curriculum design are addressed.
Sounds of Silence
Authors: Revelle Carol , Waugh Anna
Published: October 2021

This chapter juxtaposes the efforts of the authors to bring an LGBTQ+ text, Love is Love (2017), into their curriculum through a literature circle versus the hostile response of a district's administrators censoring its use in the classroom. The first section of this chapter provides a review of literature to encourage the use of diverse texts in the curriculum in support of this vulnerable population and is followed by a theoretical framework for analyzing and including LGBTQ+ texts in curriculum. The next section describes the events that occurred that led to the censorship of the literature circle and the eventual banning of the LGBTQ+ text. This section ends with a resource list to support teachers who advocate for diverse texts. The final section connects the events at the school with an analysis that demonstrates the efforts to silence the voices of LGBTQ+ students and their advocates. This case provides patterns of oppression in the hopes of naming and ending these practices and offering solidarity to others who may have these experiences.
Use of Smart Contracts and Distributed Ledger for Automation
Authors: Gautam Abhishek Kumar , Nitin Nitin
Published: October 2021

Blockchain as a service has evolved significantly from where it started as an underlying technology for Bitcoin cryptocurrency when introduced in 2008. Realization of the immense opportunities this technology possesses encouraged the development of several other Blockchain solutions such as Ethereum, which focused more on the unique competencies much beyond just the digital currency. In this chapter, the authors provided insights into the unmatchable capabilities of Blockchain to evade cyber-attacks that can facilitate a much-needed push for the scalable operation of autonomous vehicles by providing a safer and trustable ecosystem through smart contracts. The chapter also discusses the integration of Ethereum Blockchain with Confidential Consortium Framework (CFF) to overcome the shortcomings of Blockchain in terms of speed and volume. Towards the end, they talked about some of the modern technologies such as IoT and AI that can be benefitted by Blockchain.
Autonomous Vehicles
Authors: Wiseman Yair
Published: October 2021

The first car was invented in 1870 by Siegfried Marcus. Actually, it was just a wagon with an engine but without a steering wheel and without brakes. Instead, it was controlled by the legs of the driver. Converting traditional vehicles into autonomous vehicles was not just one step. The first step was just 28 years after the invention of cars, that is to say 1898. This step's concept was moving a vehicle by a remote controller. Since this first step and as computers have been becoming advanced and sophisticated, many functions of modern vehicles have been converted to be entirely automatic with no need of even remote controlling. Changing gears was one of the first actions that could be done automatically without an involvement of the driver, so such cars got the title of “automatic cars”; however, nowadays there are vehicles that can completely travel by themselves although they are not yet allowed to travel on public roads in most of the world. Such vehicles are called “autonomous vehicles” or “driverless cars”.
A Modified Cuckoo Search Algorithm for Data Clustering
Authors: Mohanty Preeti Pragyan , Nayak Subrat Kumar
Published: October 2021

Clustering of data is one of the necessary data mining techniques, where similar objects are grouped in the same cluster. In recent years, many nature-inspired based clustering techniques have been proposed, which have led to some encouraging results. This paper proposes a Modified Cuckoo Search (MoCS) algorithm. In this proposed work, an attempt has been made to balance the exploration of the Cuckoo Search (CS) algorithm and to increase the potential of the exploration to avoid premature convergence. This algorithm is tested using fifteen benchmark test functions and is proved as an efficient algorithm in comparison to the CS algorithm. Further, this method is compared with well-known nature-inspired algorithms such as Ant Colony Optimization (ACO), Artificial Bee Colony (ABC), Particle Swarm Optimization (PSO), Particle Swarm Optimization with Age Group topology (PSOAG) and CS algorithm for clustering of data using six real datasets. The experimental results indicate that the MoCS algorithm achieves better results as compared to other algorithms in finding optimal cluster centers.
Sensitivity Analysis of GFRP Composite Drilling Parameters and Genetic Algorithm-Based Optimisation
Authors: Kalita Kanak , Ghadai Ranjan Kumar , Bansod Ankur
Published: October 2021

In this article, a genetic algorithm (GA) is used for optimizing a metamodel of surface roughness (R_a ) in drilling glass-fibre reinforced plastic (GFRP) composites. A response surface methodology (RSM) based three levels (-1, 0, 1) design of experiments is used for developing the metamodel. Analysis of variance (ANOVA) is undertaken to determine the importance of each process parameter in the developed metamodel. Subsequently, after detailed metamodel adequacy checks, the insignificant terms are dropped to make the established metamodel more rigorous and make accurate predictions. A sensitivity analysis of the independent variables on the output response helps in determining the most influential parameters. It is observed that f is the most crucial parameter, followed by the t and D. The optimization results depict that the R_a increases as the f increases and a minor value of drill diameter is the most appropriate to attain minimum surface roughness. Finally, a robustness test of the predicted GA solution is carried out.
Extreme Learning Machine-Based Age-Invariant Face Recognition With Deep Convolutional Descriptors
Authors: Boussaad Leila , Boucetta Aldjia
Published: October 2021

The principal intention of this paper is to study face recognition across age progression at two levels: feature extraction and classification. In other words, this work aims to prove the benefit of replacing the Softmax layer of the Deep-Convolutional Neural Networks (CNN) by Extreme Learning Machine (ELM) classifier based on deep features computed from fully-connected layer of pre-trained AlexNet CNN model, in a context of age-invariant face recognition. Experimental results indicate that the ELM classifier combined with feature extracted by the pre-trained AlexNet CNN model worked effectively for face recognition across age progression. As significant highest mean accuracy rates are always obtained using ELM classifier. These results are more significant, following a 95% confidence level hypothesis test.
RETRACTED: Communication Strategies of Entrepreneurial Organizations in Mobile Apps Industry
Authors: Shi Wei , Weber Matthew
Published: October 2021

This research advances scholarly understanding of the strategic decisions regarding external communication during the critical period of product launch. Drawing on research about dynamic capabilities and external organizational communication, this study examines ways in which entrepreneurial organizations use silence as an effective communication strategy to reduce external uncertainty and to nurture growth during critical periods of development. Data were collected tracking the external communication of 54 entrepreneurial organizations that focus on mobile news application development. Results show a significant relationship between the attention organizations attract after product launch and an organization's performance. The greater the magnitude of change from pre-launch to post-launch, from less frequent external communication to more frequent external communication, the more likely there is to be an increase in the product performance. The findings emphasize a more nuanced understanding of external communication as a strategic tool in entrepreneurial organizations.
The Role of Marketing Knowledge Management in Enhancing Digital Financial Innovation in Commercial Banks
Authors: Hani H. Al-dmour  , Alsfour Futon , Al-Dmour Rand H. , Saifan Noor Majid
Published: October 2021

This study examines the role of marketing knowledge management (assets and capabilities) in enhancing digital financial innovation through the moderating role of employees' demographic characteristics (age, education, experience, and position) in commercial banks operating in Jordan. To accomplish this aim, a conceptual framework based on knowledge-based theory and literature review was developed. A total of 336 responses to a questionnaire survey were collected from the managers and employees working on commercial banks operating in Jordan. The empirical findings revealed that marketing knowledge management capabilities positively and significantly affect digital financial innovation. The findings also support the moderating effect of only two demographic characteristics: of employees: education and position on the relationship between marketing knowledge management and digital financial innovation in commercial banks in Jordan.
Knowledge Retention Challenges in Information Systems Development Teams
Authors: Chiu Yi-Te , Mirkovski Kristijan , Cranefield Jocelyn , Shankar Shruthi
Published: October 2021

Information systems development (ISD) is an integral part of organizational agility in today’s competitive business environment. High turnover, agile ways of working, and fluid work environments pose challenges for ISD. This paper explores the erosion of knowledge retention (KR) arising from ISD staff churn in a New Zealand-based financial organization in the aftermath of a major earthquake. In this exploratory study, the authors develop a causal model of KR in the ISD context, which articulates the challenges to and consequences of ineffective KR at the routine and exiting stages of KR. The model identifies four challenges—coordination complexity, insufficient resources for knowledge retention, insufficient attention to knowledge retention, and slow staff replacement and handover processes—that can affect the loss of ISD knowledge when routine and exiting KR fall into disarray. This study also reveals that role stress and reduced ISD agility reinforce the cycle of knowledge loss.
RETRACTED: Exploring the Dynamics of Justification in the Wake of a Rumor Outbreak on Social Media
Authors: Pal Anjan , Chua Alton Y. K. , Banerjee Snehasish
Published: October 2021

This paper explores the dynamics of justification in the wake of a rumor outbreak on social media. Specifically, it examines the extent to which the five types of justification—descriptive argumentation, presumptive argumentation, evidentialism, truth skepticism, and epistemological skepticism—manifested in different voices including pro-rumor, anti-rumor, and doubts before and after fact-checking. Content analysis was employed on 1,911 tweets related to a rumor outbreak. Non-parametric cross-tabulation was used to uncover nuances in information sharing before and after fact-checking. Augmenting the literature which suggests the online community's susceptibility to hoaxes, the paper offers a silver lining: users are responsible enough to correct rumors during the later phase of a rumor lifecycle. This sense of public-spiritedness can be harnessed by knowledge management practitioners and public relations professionals for crowdsourced rumor refutation.
Effect of Emotional Exhaustion and Knowledge Sharing on Depersonalization, Work Accomplishment, and Organizational Performance
Authors: Parayitam Satyanarayana , Usman Aktharsha Syed , Olson Bradley J. , Shea Timothy
Published: October 2021

The objective of the present study is to empirically investigate the relationship between emotional exhaustion and knowledge sharing of individual and organizational outcomes. Data was collected from 672 respondents from the information technology (IT) sector. The results from path analysis revealed that emotional exhaustion is (i) positively related to depersonalization, and (ii) negatively related to work accomplishment and organizational performance. The results also reveal that knowledge sharing is (i) negatively related to depersonalization, and (ii) positively related to work accomplishment and organizational performance. However, depersonalization is not negatively related to organizational performance. As predicted, work accomplishment is positively related to organizational performance. The diametrically opposite results of emotional exhaustion and knowledge sharing are particularly interesting. The implications for management and practicing mangers are discussed.
RETRACTED: Human Capital as a Mediating Factor of Structural Capital and Value Addition
Authors: Jardón Carlos-Maria Fernandez , Silva Amandio F. C.
Published: October 2021

Structural capital is one of the components of intellectual capital. The measurement is essential in order to obtain the real value of intellectual capital and its influence on the profitability of the business. The measurement of structural capital value addition can be done directly or via the mediating effect of another component of intellectual capital (i.e., human capital or relational capital). Human capital has been selected as the mediating component for this study based on findings of previous studies that advocate its importance as a major determinant that enhances structural capital changes. This paper aims at measuring the influence of human capital as a mediating factor on the capacity of structural capital value addition for the period of 2002-2018, for Galicia (Spain) and Portugal.
Role of Reinforcement Particle Size and Its Dispersion on Room Temperature Dry Sliding Wear of AA7075/TiB2 Composites
Authors: Meti Vinod Kumar V. , Raju G. U. , Siddhalingeshwar I. G. , Gaitonde Vinayak Neelakanth
Published: October 2021

Aluminum alloy based metal matrix composites (AMCs) are widely accepted material in the aerospace, automotive, military, and defence applications due to lightweight and high strength. For tribological applications, high-performance wear-resistant materials like AMCs are the candidate materials. In this investigation, AA7075 based composites with different size TiB2 particles were fabricated using in-situ and ultrasound casting techniques (UST). The AMCs were tested using pin-on-disc tribo tester and the effects of different sized TiB2 particles on wear resistance of AA7075/TiB2 composites have been investigated. The wear resistance of AA7075/TiB2 composite fabricated using UST is found to significantly improve when compared to base alloy and also in-situ composite due to refinement in the particle size, reduced the agglomeration, and improved the distribution of TiB2 particles. The test results also revealed the existence of a mixture of mechanically mixed Al–Zn–Fe intermetallic alloy and oxides of these elements.
Prediction of Surface Roughness During Dry Sliding Wear
Authors: Lal Basant , Dey Abhijit , Wani Mohamamd Farooq
Published: October 2021

Due to the relatively low strength and poor wear resistance of unalloyed titanium and its good mechanical properties, corrosion resistance, and biocompatibility. Ti6Al4V has been extensively used in various type of application including aerospace, biomedical and offshore industries. The goal of this research is to enhance the surface properties of the high strength alloys are examine such as Ti6Al4V pin sliding against Al2O3disc, due to the various surfaces roughness parameters. The COF and the wear rate were found to be lower at higher applied load due to higher frictional heating leading to thermal oxidation and thereby formation of several mm thick tribo-layers on the worn surfaces. Characterization of the tribological sample was performed using a scanning electron microscope (SEM) equipped with energy dispersive X-ray analysis (EDAX) to ensure that the wear pattern and debris morphologies of the Ti6Al4V and alumina disks were distinct, suggesting a surface roughness value determined by 3D profilometer at various load and sliding speed of 0.01ms-1.
An Ensemble of Random Forest Gradient Boosting Machine and Deep Learning Methods for Stock Price Prediction
Authors: Shrivastav Lokesh Kumar , Kumar Ravinder
Published: October 2021

Stochastic time series analysis of high-frequency stock market data is a very challenging task for the analysts due to the lack availability of efficient tool and techniques for big data analytics. This has opened the door of opportunities for the developer and researcher to develop intelligent and machine learning based tools and techniques for data analytics. This paper proposed an ensemble for stock market data prediction using three most prominent machine learning based techniques. The stock market dataset with raw data size of 39364 KB with all attributes and processed data size of 11826 KB having 872435 instances. The proposed work implements an ensemble model comprises of Deep Learning, Gradient Boosting Machine (GBM) and distributed Random Forest techniques of data analytics. The performance results of the ensemble model are compared with each of the individual methods i.e. deep learning, Gradient Boosting Machine (GBM) and Random Forest. The ensemble model performs better and achieves the highest accuracy of 0.99 and lowest error (RMSE) of 0.1.
Crowd Abnormality Detection Using Optical Flow and GLCM-Based Texture Features
Authors: Lalit Ruchika , Purwar Ravindra Kumar
Published: October 2021

Detection of abnormal crowd behavior is one of the important tasks in real-time video surveillance systems for public safety in public places such as subway, shopping malls, sport complexes and various other public gatherings. Due to high density crowded scenes, the detection of crowd behavior becomes a tedious task. Hence, crowd behavior analysis becomes a hot topic of research and requires an approach with higher rate of detection. In this work, the focus is on the crowd management and present an end-to-end model for crowd behavior analysis. A feature extraction-based model using contrast, entropy, homogeneity, and uniformity features to determine the threshold on normal and abnormal activity has been proposed in this paper. The crowd behavior analysis is measured in terms of receiver operating characteristic curve (ROC) & area under curve (AUC) for UMN dataset for the proposed model and compared with other crowd analysis methods in literature to prove its worthiness. YouTube video sequences also used for anomaly detection.
Experimental Study to Investigate Dune Sand Improvement by Adding Fine Waste Materials
Authors: Qureshi Mohsin Usman , Al Kindi Ghassan , Alsaidi Maryam Said
Published: October 2021

Dune sands are poorly graded collapsible soils lacking fines. This experimental study explored the possibility of sustainable invigoration of fine waste materials in dune sand to improve the geotechnical properties. The fine wastes used in this study are reservoir sediments and marble waste powder. The fine waste powder was mixed with dune sand at different percentages (5, 10, 25, 50%) to study the gradation, void ratio and, compaction characteristics. A machine has been manufactured to elucidate the maximum void ratio using a developed and manufactured linear-axis 3D clay printer arm. The geotechnical properties of sand-waste mixes delineated in this study reveals the enhancement in compaction and gradation characteristics of dune sand. According to the results, the binary mixture of dune sand with 25% of marble waste and 50% of reservoir sediment gives the highest maximum dry density. Thus, for improving dune sand’s geotechnical characteristics, the addition of fine marble waste and reservoir sediment to the dune sand is an environment-friendly solution.
Buccal mucosa graft ureteroplasty for a long proximal ureteric stricture
Authors: Sivashankar M. , Nandasena A. C. N.
Published: October 2021

No abstract available
Hospitalization and Mortality Trends among Patients with Confirmed COVID-19 in the United States, April through August 2020
Authors: Nguyen Jennifer L. , Benigno Michael , Malhotra Deepa , Reimbaeva Maya , Sam Ziphora , Chambers Richard , Hammond Jennifer , Emir Birol
Published: October 2021

Background

The United States has experienced high COVID- 19 case counts, hospitalizations, and death rates. This retrospective analysis reports changing trends in the demographics and clinical outcomes of hospitalized US COVID-19 patients between April and August 2020.

Design and methods

The Premier Healthcare Database Special Release was used to examine patient demographics of hospitalized COVID-19 patients from all US Census Bureau divisions. Demographics included age, sex, race, and ethnicity. Clinical outcomes included in-hospital mortality, intensive care unit (ICU) admission, and receipt of invasive mechanical ventilation.

Results

Overall, 146,491 hospitalized COVID-19 patients were included (mean [SD] age, 61.0 [18.4] years; 51.7% male; 29.6% White non-Hispanic). Monthly total hospitalizations decreased from 44,854 in April to 18,533 in August; ICU admissions increased from 19.8% to 23.6%, and ventilator use and inpatient mortality decreased from 18.6% to 14.5% and 21.0% to 11.4%, respectively. Inpatient mortality was highest in the Middle Atlantic division (20.3%), followed by the New England (19.0%), East North Central (14.2%), and Mountain (13.7%) divisions. Black non-Hispanic patients were overrepresented among hospitalizations (19.0%); this group comprises 12.2% of the US population. Patients aged <65 years made up 53% of hospitalizations and had lower inpatient mortality than those aged ≥65 years.

Conclusions

Hospitalizations, ventilator use, and mortality decreased, while ICU admission rates increased from April to August 2020. Older individuals and Black non-Hispanics were found to be at elevated risk of severe outcomes. These trends could inform ongoing patient care and US public health policies to limit the further spread of SARS-CoV-2.
COVID-19 Patients with Mild Symptoms or without Symptom Using Residential Treatment Center Model
Authors: Kim Song Yi , Kim Ji Young , Lee Gyeongsil , Yun Jae Moon , Cho BeLong
Published: October 2021

Background: The rapid rise in coronavirus disease worldwide has drastically limited the availability of hospital facilities for patients. Residential treatment centers were opened in South Korea for the admission of asymptomatic or patients with mild symptoms. This study discusses the appropriateness of the admission criteria set by the centers in a pandemic situation, the prioritization of patients for admission, and ways to minimize the risk of self-isolation.Methods: A total of 217 low-risk patients (n=217) were admitted to the Nowon Residential Treatment Center between August 22 and October 14, 2020. The following criteria were met at the time of admission: patients (1) were asymptomatic or had mild symptoms, (2) had either a controlled or no underlying chronic disease, and (3) did not need oxygen treatment. Among them, 202 patients who were eligible for inclusion in the study were retrospectively investigated through periodic interviews.Results: Of the 202 patients, 153 satisfied the criteria for symptomatic isolation standards, and 25 for asymptomatic isolation standards. The clinical conditions of 24 patients were aggravated, and these patients were transferred to other hospitals, among which 12 had persistent fever and 13 were suffering dyspnea with oxygen saturation (SpO2) <95%.Conclusion: In the event of another large-scale epidemic, it would be appropriate to prioritize accommodating patients who are elderly or have underlying diseases and self-isolate young patients with no underlying diseases and provide them with SpO2 meters and thermometers to self-measure SpO2 and body temperature.
"Heads in the sand"
Authors: Office Editorial
Published: October 2021

No abstract available.
A successful treatment with intravenous lipid emulsion therapy in a child with verapamil poisoning
Authors: Havan Merve , Kendirli Tanıl , Özcan Serhan , Doğan Melih Timuçin , Yiğit Ahmet Onur , Uçar Tayfun
Published: October 2021

In recent years, intravenous lipid emulsion therapy (ILE) was used for lipophilic drug intoxications, and successful results were obtained. In the literature, there is a small number of reported cases about verapamil intoxication and ILE therapy in the pediatric age group. We used ILE therapy in a 14-year-old girl with verapamil intoxication in the 2nd h of the pediatric intensive care unit stay, before using traditional treatments such as glucagon and hyperinsulinemic euglycemia. She had resistant bradycardia and hypotension which was unresponsive to inotropic agents and a successful result was obtained after using ILE treatment. We believe our report may contribute to the early use of ILE therapy for toxicity with calcium channel blockers such as verapamil in pediatric patients.
Comparative evaluation of the efficacy of intravenous paracetamol and ibuprofen on the treatment of tonsillopharyngitis with fever
Authors: Oncel Gizem , Yilmaz Atakan , Sabirli Ramazan , Cimen Yesim Kinaci , Ozen Mert , Seyit Murat , Turkcuer Ibrahim , Cimen Uzeyir
Published: October 2021

OBJECTIVE:

Tonsillopharyngitis is one of the constituents of upper respiratory tract infection (URTI). Fever is a URTI symptom requiring treatment due to the occurrence of discomfort and high fever-based complications. This study primarily sets out to observe and compare the efficacy of intravenous administration of paracetamol and ibuprofen drugs on fever in adult patients with tonsillopharyngitis.

METHODS:

This study was performed in a prospective, randomized controlled, double-blind design. The study population was divided as Group 1 (treated with paracetamol) and as Group 2 (treated with ibuprofen). While the first group was treated with paracetamol as 1000 mg in 150 ml normal saline, the second group was treated with ibuprofen as 400 mg in 150 ml normal saline. The primary outcome was the decrease in fever at 15, 30, and 60 min, while the secondary outcome was the need for additional treatment after 60 min.

RESULTS:

One hundred and eighty-five patients were included in the final analysis. The mean age of the paracetamol group (57.4% male) was 28.36 ± 9.6, whereas that of the ibuprofen group (54.9% male) was 27.45 ± 7.98. Fever was reduced significantly between 0 and 60 min in both groups (P ≤ 0.001 and P ≤ 0.001, respectively). Although the antipyretic effect of ibuprofen was more pronounced in the early period than that of paracetamol, no significant difference was noted between the two groups in terms of fever drop between 0 and 60 min (P = 0.350).

CONCLUSION:

Although both drugs prove effective in controlling fever at the 60 min, stronger efficacy of ibuprofen in the first 15 min may enable rapid discharge from the emergency department.
Selective intubation with endotracheal tube introducer in difficult airway
Authors: Özerol Hakan , Şancı Emre , Karakayalı Onur , Aydın Erdem , Halhallı Hüseyin Cahit
Published: October 2021

BACKGROUND:

Selective lung intubation is a life-saving procedure in emergency departments. While various equipment can be used in selective lung intubation, most of this equipment is not readily available; therefore, single-lumen endotracheal intubations are performed for rapid interventions.

MATERIALS AND METHODS:

This study was designed as a randomized, prospective, cross-over study using the 90° rotation technique for selective intubation on a manikin model with and without endotracheal tube introducer (ETI) in difficult airway settings. Forty-six emergency physicians were included in the study. The primary outcome was evaluating time to selective intubations, and secondary outcomes were first and second attempt success rates and the self-perceived difficulty level of each method according to the participants.

RESULTS:

The mean time to the first successful endotracheal intubation was significantly longer for both right selective and left selective intubations with ETI utilization than without ([39.71 ± 9.83 vs. 21.86 ± 5.94 s], [P < 0.001]), ([42.2 ± 10.81 vs. 26.23 ± 7.97 s], [P < 0.001], respectively). The first-pass success rate did not differ for right selective intubation with or without an ETI (45/46 [97.8%] and 45/46 [97.8%], respectively). However, the first-pass success rate for left selective intubation was significantly higher with ETI as compared to without an ETI (30/46 [65.2%] and 13/46 [28.3%], respectively) (P < 0.001).

CONCLUSIONS:

While the success rates of right selective intubation were the same, the left selective intubation success rates with ETI are higher than the styletted endotracheal tube, which can be strong evidence for this method's applicability in practice. Expanding the use of ETI and increasing the experience of the practitioners can contribute to further success.
CXCR4 is a valuable poor prognostic marker for chronic lymphocytic leukemia
Authors: Asfour Inas , Elsalakawy Walaa A. , Sallam Mohamed T.H. , Razzaz Mostafa K.El
Published: October 2021

Background

Chronic lymphocytic leukemia (CLL) is one of the common chronic lymphoproliferative disorders (lymphoid neoplasms). It is characterized by a progressive accumulation of functionally incompetent lymphocytes, which are usually monoclonal in origin. CLL is a heterogeneous disease; thus, in some cases, the disease progresses so slowly that treatment is not required, but in others, a more aggressive form of the disease develops. CXCR4 (CD184) is a chemokine and chemokine receptor pair playing critical roles in tumor genesis. It is overexpressed in many hematological malignancies including acute myeloid leukemia and non-Hodgkin's lymphoma and generally correlates with a poor prognosis.

Aim

To evaluate the clinical utility of CXCR4 expression in patients with CLL as a possible predictor of disease outcome.

Patients and methods

This is a prospective study conducted on 33 adult patients with newly diagnosed CLL. Expression of CXCR4 was determined by flow cytometry on either peripheral blood or bone marrow samples. Correlation with the course of the disease and the known CLL prognostic parameters was done initially and after 6 months of follow-up.

Results

CXCR4 expression was positively correlated with absolute lymphocytic count, Rai score, β2 microglobulin, and lactate dehydrogenase levels. It was negatively correlated with hemoglobin and platelet counts, overall response rate, and 6-month disease-free survival.

Conclusion

We conclude that CXCR4 is a valuable poor prognostic marker for CLL. Its higher level of expression is associated with inferior response to therapy and lower disease-free survival.
Diagnostic and prognostic value of neuron-glial antigen 2 expression in adult acute myeloid leukemia
Authors: Gawaly Amr M. , Elkholy Rasha A. , Hagag Rasha Y. , Abd El-Lateef Amal E. , Allam Alzahraa A.
Published: October 2021

Background

Acute myeloid leukemia (AML) is a hematopoietic stem cell disorder characterized by a block in differentiation of hematopoiesis, resulting in growth of a clonal population of neoplastic cells or blasts. Neuron-glial antigen 2 (NG2) is not expressed by normal hematopoietic stem cells but expressed on blast cells in adult AML. NG2 has been incorporated in diagnostic panels for immunophenotyping of leukemic patients because of its positive predictive value for Mixed Lineage Leukemia (MLL) rearrangements.

Aims

To assess NG2 expression in adult patients with AML and its correlation with disease-free survival.

Patients and methods

A total of 60 patients were divided into two groups: 40 newly diagnosed patients with AML and 20 patients diagnosed as having hypersplenism used as a control group. Leukemic patients were diagnosed on the basis of clinical presentation, morphological and cytochemical examination of peripheral blood and bone marrow smears, as well as immunophenotyping criteria for diagnosis of AML. NG2 expression was evaluated in the two groups using flow cytometry.

Results

No significant differences were found in both age and sex in different patient groups. NG2 expression in the patient group versus control group showed a statistically significant difference. There was no statistically significant difference regarding complete blood count, lactate dehydrogenase, and erythrocyte sedimentation rate, as well as blast percentage in the peripheral blood and in the bone marrow on comparing NG2-positive group and NG2-negative group. There is a significant increase in disease-free survival and overall survival in the negative NG2 expression than in the positive NG2 expression group (P=0.043).

Conclusion

NG2 expression has a major role in the outcome of patients with AML. NG2 expression analysis can be used as a prognostic marker in newly diagnosed patients with AML. NG2 could be a target for therapy by using anti-NG2 antibody in a subset of patients with AML who do not respond to conventional therapy.
Effect of Charlson comorbidity index on vascular events and survival in Philadelphia chromosome-negative myeloproliferative neoplasms
Authors: Ahmed Shimaa A. , Aly Mai M.
Published: October 2021

Background

Thromboembolic events and bleeding episodes are the main complications of myeloproliferative neoplasms (MPNs). Comorbidity is a well-known independent prognostic factor for patients with cancer that affects overall survival.

Aim

Our aim is to detect comorbidities among patients with Philadelphia chromosome-negative MPNs and to study how comorbidities affect survival and vascular events.

Patients and methods

A total of 190 patients with Philadelphia chromosome-negative MPNs were diagnosed between January 2014 and December 2018 in South Valley and Assiut University Hospitals. Charlson Comorbidity Index (CCI) was applied to evaluate patients. Median age was 57.5 years (range, 20–85). Overall, 50 (26.3%) patients had no comorbidities (low), 83 (43.7%) had a CCI 1–2 (moderate), and 57 (30%) had a CCI more than 2 (severe).

Results

There were no significant differences between patients with CCI less than 2 and patients with CCI more than or equal to 2 regarding sex, splenomegaly, white blood cell count, platelet count, and JAK II positivity. Significantly older ages (64.7±9 vs. 50.8±9, P<0.001), lower hemoglobin (5±12.3 vs. 14.6±5, P=0.046), and higher lactate dehydrogenase (P=0.004) were detected in patients with CCI more than or equal to 2. A significant association regarding pruritus and erythromelalgia was found among patients who had CCI more than or equal to 2 compared with patients with CCI less than 2 (P=0.038 and 0.025, respectively). Thrombosis was more frequent with CCI more than or equal to 2 (P<0.001) as well as bleeding (P=0.042). Overall survival and progression-free survival differed significantly between the different CCI groups (P≤0.001 and 0.003, respectively).

Conclusion

In conclusion, comorbidity has a negative prognostic effect on patients with Philadelphia chromosome-negative MPNs, which might elicit to be incorporated into prognostic models, with larger prospective studies needed for validation.