bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of cell-mediated immunity in people with long COVID
Authors: Montes Nerea , Domènech Èlia , Guerrero Sílvia , Oliván-Blázquez Bárbara , Magallón-Botaya Rosa 
Published: June 2021

ABSTRACTIntroductionThe objective of this study is to analyse the specific immune response against SARS-CoV-2 in those affected by Long Covid (LC), attributable to T cells (cell-mediated immunity) and to carry out a parallel analysis of the humoral response and lymphocyte typing.MethodologyDescriptive cross-sectional study of 74 patients with LC for at least 4 months since diagnosis. The collected data were: information on the COVID-19 episode and the persistent symptoms, medical history and a specific cell-mediated immunity to SARS-CoV-2 through flow cytometry, assessing the release of interferon-gamma (IFN-Ɣ) by T4 lymphocytes, T8 lymphocytes and NK cells. Descriptive and comparative analyses were carried out.ResultsPatients with LC had negative serology for Covid-19 in 89% of cases but 96% showed specific cellular immunity to SARS-CoV-2 an average of 9.5 months after infection: 89% of this response corresponded to T8 lymphocytes, 58% to NK cells, and 51% to T4 lymphocyte (20% negligibly positive). Most of them had altered immune cell typing and we found that T4 lymphocyte counts were low in 34% of cases and NK cell high in 64%. Macrophage populations were detected in the peripheral blood of 7% of them. Patients displayed a higher percentage of illnesses related to &[Prime]abnormal&[Prime] immune responses, either preceding SARS-CoV-2 infection (43%) or following it in 23% of cases.ConclusionThe immune system appears to have an important involvement in the development of LC and viral persistence could be the cause or consequence of it. Further analysis with a control group should be performed.
Depressive and anxiety symptoms and COVID-19-related factors among men and women in Nigeria
Authors: Oginni Olakunle Ayokunmi , Oloniniyi Ibidunni Olapeju , Ibigbami Olanrewaju , Ugo Victor , Amiola Ayomipo , Ogunbajo Adedotun , Esan Oladoyin , Adelola Aderopo , Daropale Oluwatosin , Ebuka Matthew , Mapayi Boladale 
Published: June 2021

AbstractDespite the greater adverse economic impacts in low and middle-income (LAMI) compared to high-income countries, fewer studies have investigated the associations between COVID-19-related stressor and mental health in LAMI countries. The objectives of this study were to determine the associations between COVID-19-related stressors and anxiety and depressive symptoms while controlling for known risk and protective factors and to investigate any sex differences. An online survey was carried out to assess sociodemographic, psychosocial (previous mental health conditions, sexual orientation, intimate partner violence and perceived social support) and COVID-19-related variables. Hierarchical linear regression was carried out with anxiety and depressive symptoms as separate outcomes. Of the COVID-19-related factors, testing positive for COVID-19 infection, having COVID-19 symptoms, having other medical conditions, self-isolating due to COVID-19 symptoms, worry about infection, perception of the pandemic as a threat to income and isolation during the lockdown were significantly associated with higher anxiety and depressive symptoms. Of these, worry about infection, isolation during lockdown and disruption due to the pandemic retained independent associations with both outcomes. The variance in anxiety and depressive symptoms explained by COVID-19-related factors was larger in women (6.1% and respectively) compared to men (6.1% and respectively). COVID-19-related stressors are associated with higher anxiety and depressive symptoms, with these effects being larger in men compared to women. Enhancing social support can be an affordable strategy to mitigate this risk but this needs to be investigated using appropriate designs.
Aminobenzoic acid functionalized graphene oxide as environment-friendly corrosion inhibitors for Q235 steel in HCl solution: experimental and DFT studies
Authors: Ma Baoguang , Chen Cheng , Xie Xiaojun , Chen Yanhui , Zhang Qiuyu , Lv Dong , Liu Zhenguo 
Published: June 2021

Purpose
The purpose of this study is to provide effective and environmental-friendly corrosion inhibitors derived from graphene oxide for Q235 steel.

Design/methodology/approach
Nontoxic and environment-friendly 4-aminobenzoic acid was used to functionalize graphene oxide via amidation and diazotization. The obtained amidation 4-aminobenzoic acid functionalized graphene oxide (PAGO) and diazotization 4-aminobenzoic acid functionalized graphene oxide (PDGO) were characterized by FTIR, Raman and TEM, while the inhibition efficiencies were analyzed by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). Furthermore, theoretical inhibition efficiencies were investigated by density functional theory (DFT) approach.

Findings
At a concentration of 40 ppm, the maximum inhibition efficiency of PAGO and PDGO were 97.90% and 96.72% in EIS measurement, respectively, which were in accordance with PDP data. Moreover, experimental results were supported by DFT-based quantum chemical calculation.

Originality/value
Environmental-friendly PAGO and PDGO were synthesized successfully. The synthetic inhibitors exhibited excellent inhibition efficiencies in EIS and PDP measurements. Furthermore, a computational study using DFT supported the trend that PAGO was better inhibitor than PDGO.
Aerodynamic design and optimization of propellers for multirotor
Authors: Klimczyk Witold Artur 
Published: June 2021

Purpose
This paper aims to present a methodology of designing a custom propeller for specified needs. The example of propeller design for large unmanned air vehicle (UAV) is considered.

Design/methodology/approach
Starting from low fidelity Blade Element (BE) methods, the design is obtained using evolutionary algorithm-driven process. Realistic constraints are used, including minimum thickness required for stiffness, as well as manufacturing ones – including leading and trailing edge limits. Hence, the interactions between propellers in hex-rotor configuration, and their influence on structural integrity of the UAV are investigated. Unsteady Reynolds-Averaged Navier–Stokes (URANS) are used to obtain loading on the propeller blades in hover. Optimization of the propeller by designing a problem-specific airfoil using surrogate modeling-driven optimization process is performed.

Findings
The methodology described in the current paper proved to deliver an efficient blade. The optimization approach allowed to further improve the blade efficiency, with power consumption at hover reduced by around 7%.

Practical implications
The methodology can be generalized to any blade design problem. Depending on the requirements and constraints the result will be different.

Originality/value
Current work deals with the relatively new class of design problems, where very specific requirements are put on the propellers. Depending on these requirements, the optimum blade geometry may vary significantly.
Coordinated financial statements: what-is, what-if and how-much questions
Authors: Robison Lindon J. , Barry Peter J. 
Published: June 2021

PurposeThis paper aims to use coordinated financial statements' system properties that include exogenous and endogenous variables to answer important questions. These questions include the following: What is the financial condition of the firm? What if there is a change in the firm's exogenous variable(s) – how will the financial condition of the firm change? And, how much of a change in the firm's exogenous variable(s) is required for the firm to reach its financial goal(s)?Design/methodology/approachThis paper uses coordinated financial statements to construct solvency, profitability, efficiency, liquidity and leverage (SPELL) ratios to answer the question: what is the financial condition of the firm? It answers what-if questions by changing an exogenous variable(s) and recalculating SPELL ratios. It answers how-much questions by using Excel's Goal Seek algorithm to find the required change in an exogenous variable to reach a firm's goal.FindingsThe authors find that coordinated financial statements' system properties can be used to answer important what-is, what-if and how-much questions about the firm.Research limitations/implicationsThe usefulness of coordinated financial statements' system properties to answer what-is, what-if and how-much questions about the firm depends – mostly on the accuracy of exogenous data used to represent the firm's external financial environment. Furthermore, the usefulness of what-if and how-much analysis depends on how appropriate the changes are in exogenous variables used to represent alternative scenarios.Practical implicationsUsing coordinated financial statements' system properties to answer what-is, what-if and how-much questions provides the firm's financial manager the tools to not only asses the firm's current financial condition but also to assess its ability to respond to opportunities and threats posed by future scenarios.Social implicationsThe ability to assess the financial condition of a firm and to assess its strengths and weaknesses in key to making sound financial decisions. In addition, the consistency imposed on coordinated financial statements makes it an effective tool for discovering errors in its data.Originality/valueThe authors know of no similar work.
Productivity growth, catching-up and technology innovation in microfinance institutions in India: evidence using a bootstrap Malmquist Index approach
Authors: Khan Asif , Gulati Rachita 
Published: June 2021

PurposeThis paper aims to examine the total factor productivity (TFP) change and its components: efficiency change and technical change in microfinance institutions (MFIs) in India operating from 2005 to 2018. The study also scrutinizes the variations in productivity levels across the distinct organizational form and size groups of MFIs. In addition to this, the authors identify the contextual factors that determine TFP growth, catching-up and technology innovation in MFIs.Design/methodology/approachThe study employs a smooth homogeneous bootstrap estimation procedure of Simar and Wilson (1999) for obtaining reliable estimates of Malmquist indices –productivity and its components – in a data envelopment analysis (DEA) framework for individual MFIs. In order to identify the determinants of productivity change and its components, the study follows Simar and Wilson's (2007) guidelines and applies a bootstrap truncated regression model. The double bootstrap procedure performs well, both in terms of allowing correct estimation of bias and deriving statistically consistent productivity estimates in the first and root mean square errors in the second stage of the analysis.FindingsThe empirical results reveal that the MFIs have shown average productivity growth of 6.70% during the entire study period. The observed productivity gains are primarily contributed by a larger efficiency increase at the rate of 4.80%, while technical progress occurs at 2.3%. Nonbanking financial companies (NBFC)-MFIs outperformed non-NBFC-MFIs. Small MFIs show the highest TFP growth in terms of size groups, followed by the large MFIs and medium MFIs. The bootstrap truncated regression results suggest that the credit portfolio, size and age of MFIs matter in achieving higher productivity levels.Practical implicationsThe practical implication drawn from the study is that the Indian MFI industry might adopt the latest technology and innovations in the products, risk assessment and credit delivery to improve their productivity levels. The industry must focus on enhancing the managerial skill of its employees to achieve a high productivity level.Originality/valueThis study is perhaps the initial attempt to explain the productivity behavior of MFIs in India by deploying a statistically robust double bootstrap procedure in the DEA-based Malmquist Productivity Index (MPI) framework. The authors estimate the bias-adjusted productivity index and its decompositions, which represent more reliable and statistically consistent estimates. For contextual factors responsible for driving productivity change, the study deploys a bootstrap truncated regression approach.
The COVID-19 pandemic, social sustainability and global supply chain resilience: a review
Authors: Sajjad Aymen 
Published: June 2021

Purpose
The purpose of this paper is to examine the impacts of the COVID-19 pandemic on global supply chain sustainability and provide an important pathway to develop an initial understanding of how organizations can develop more resilient and socially sustainable supply chains in a post-COVID world.

Design/methodology/approach
To gain fresh insights on the effects of the COVID-19 pandemic on supply chain social sustainability and resilience issues, an extensive literature review was conducted. To this end, recent scholarly research articles, articles from practitioner journals, magazine articles and policy documents and reports, as well as blogs and briefings published by international organizations were critically reviewed.

Findings
The findings suggest that the COVID-19 pandemic has been associated with a major shake-up of global supply chain operations and has contributed to varied sustainability outcomes. While the pandemic caused reductions in greenhouse gas emissions and air pollution, it has had serious social implications for the livelihoods and well-being of workers and their families. The findings further suggested that it is imperative for companies to build resilience in their global supply chain operations to better respond to future shocks and disruptions by adopting strategies such as employee protection schemes, advanced digital technologies, diversification, localization and regionalization and stakeholder collaboration.

Originality/value
This review paper contributes to emerging global supply chain sustainability literature and practice by synthesizing and explicating the impacts of the COVID-19 pandemic on supply chain social sustainability and resilience. In addition, this paper offers some practical recommendations to enhance the social sustainability impacts and resilience of global supply chains in a post-COVID world.
Artificial intelligence for hospitality big data analytics: developing a prediction model of restaurant review helpfulness for customer decision-making
Authors: Lee Minwoo , Kwon Wooseok , Back Ki-Joon 
Published: June 2021

Purpose
Big data analytics allows researchers and industry practitioners to extract hidden patterns or discover new information and knowledge from big data. Although artificial intelligence (AI) is one of the emerging big data analytics techniques, hospitality and tourism literature has shown minimal efforts to process and analyze big hospitality data through AI. Thus, this study aims to develop and compare prediction models for review helpfulness using machine learning (ML) algorithms to analyze big restaurant data.

Design/methodology/approach
The study analyzed 1,483,858 restaurant reviews collected from Yelp.com. After a thorough literature review, the study identified and added to the prediction model 4 attributes containing 11 key determinants of review helpfulness. Four ML algorithms, namely, multivariate linear regression, random forest, support vector machine regression and extreme gradient boosting (XGBoost), were used to find a better prediction model for customer decision-making.

Findings
By comparing the performance metrics, the current study found that XGBoost was the best model to predict review helpfulness among selected popular ML algorithms. Results revealed that attributes regarding a reviewer’s credibility were fundamental factors determining a review’s helpfulness. Review helpfulness even valued credibility over ratings or linguistic contents such as sentiment and subjectivity.

Practical implications
The current study helps restaurant operators to attract customers by predicting review helpfulness through ML-based predictive modeling and presenting potential helpful reviews based on critical attributes including review, reviewer, restaurant and linguistic content. Using AI, online review platforms and restaurant websites can enhance customers’ attitude and purchase decision-making by reducing information overload and search cost and highlighting the most crucial review helpfulness features and user-friendly automated search results.

Originality/value
To the best of the authors’ knowledge, the current study is the first to develop a prediction model of review helpfulness and reveal essential factors for helpful reviews. Furthermore, the study presents a state-of-the-art ML model that surpasses the conventional models’ prediction accuracy. The findings will improve practitioners’ marketing strategies by focusing on factors that influence customers’ decision-making.
Self-organisation and supply chain agility: empirical evidence from humanitarian relief operations in a developing country
Authors: Mutebi Henry , Muhwezi Moses , Munene John C. Kigozi 
Published: June 2021

PurposeThe purpose of this study was to establish whether self-organisation and its components matter for supply chain agility in the context of humanitarian relief operations in a developing country, Uganda.Design/methodology/approachThis study adopted a cross-sectional design to collect data from a sample of 101 humanitarian organisations (HOs) that deliver relief to Bidi-Bidi refugee settlement in Uganda.FindingsBased on the findings, self-organisation explains 56% of the variance in supply chain agility.Research limitations/implicationsSince the study was cross-sectional, changes in the perception of the subject matter could not be established. Hence, a longitudinal approach was recommended for subsequent studies. Data was collected only from HOs that deliver relief services in Bidi-Bidi refugee settlement.Practical implicationsIt is recommended that managers of HOs should ensure that their organisations have flexible, adaptive structures that can affect self-organisation during emergencies so as to increase the speed with which they respond to victims' needs.Originality/valueThis study generates significant empirical evidence on a less studied phenomenon in the humanitarian sector. It vividly highlights the effect of self-organisation on building supply chain agility.
Temporary and permanent aspects of project organizing – operation and maintenance of road infrastructure
Authors: Nilsson Vestola Emilia , Eriksson Per Erik , Larsson Johan , Karrbom Gustavsson Tina 
Published: June 2021

PurposeThe purpose of this paper is to explore the interdependencies between temporary and permanent aspects of project organizing and how they affect the management of public infrastructure operation and maintenance (O&M) activities.Design/methodology/approachThe paper applies a case study approach and uses Lundin and Söderholm's (1995) framework of the temporary organization (with the themes of time, task, team and transition) to distinguish between temporary and permanent aspects of organizing two infrastructure O&M projects.FindingsThis paper adds to the literature on temporary organizations by recognizing a mixture of temporary and permanent aspects of project organizing in an empirical project-level example. In line with previous research, the themes of time, task, team and transition were shown to be interdependent. Furthermore, the paper broadens the theory of temporary organizations by presenting a project organization with significant permanent aspects.Practical implicationsProject managers of public sector projects need to be aware of the possible mixture of temporary and permanent aspects of project organizing. Management of projects that are found to have a mixture of temporary and permanent aspects should combine the perspectives and management practices of both temporary and permanent organizing. Not acknowledging permanent aspects could lead to management that is not adapted to the prerequisites of project organizing in this context.Originality/valueThe findings further develop the literature on temporary organizations by recognizing that there is not only a mixture of temporary and permanent aspects between the temporary organization and its permanent environment but there is also a mixture of temporary and permanent aspects of organizing within project organizations.
Restrictions’ acceptance and risk perception by young generations in a COVID-19 context
Authors: Seabra Claudia , AlAshry Miral , Çınar Kevser , Raja Irfan , Reis Manuel , Sadiq Najma 
Published: June 2021

Purpose
The purpose of this study is to analyze the impact of the acceptance of national governments’ restrictions imposed due to the COVID-19 pandemic on the citizens’ safety perceptions of daily life and future plans. In particular, the aim is to examine the relationship among the citizens who belong to Generations Y and Z and who represent the future of tourism markets, as tourists and as host communities, in three important receiving countries, namely, Egypt, Portugal and Turkey.

Design/methodology/approach
This pilot project gathers data from three important receiving countries located on two continents involving 348 residents from Generations Y and Z. To identify the factors underlying the “acceptance of restrictions and measures” and the “Impacts of the COVID-19 threat on safety perceptions” a factor analysis was carried out. Notably, Pearson's correlation coefficient and a multiple linear regression analysis allowed to analyze the relationships between the two factors and a Kruskal–Wallis test was used to assess the influence of individuals’ country of residence.

Findings
The results reveal that in general, young generations accepted the measures and restrictions imposed by the respective governments. In addition, the present pandemic has a strong impact on their safety perception in daily lives and future plans to travel. Moreover, results prove that between the three countries there are dissimilarities showing that the countries' situation regarding COVID-19 influences those two dimensions.

Research limitations/implications
This study adds to the development of studies on the impacts of health risks in tourism activity, specifically on the safety measures adopted and their impacts on local receiving communities. It shows that the current pandemic is severely affecting the daily lives and plans for the future of citizens and tourists, which is in accordance with previous studies.

Practical implications
The outcome of this study paves the way for policy-makers in the tourism industry because it presents experiences from Generations Y and Z members, future customers and tourist products consumers, but also from receiving communities.

Social implications
The results of this study bring some light on how local communities, specifically, the younger generations, are facing this pandemic period and on the impact it has on the way they face daily life, future plans and on their level of acceptance of a sector as important as tourism.

Originality/value
To the knowledge, besides the relevant studies already conducted on the impact of the COVID-19 crisis on the tourism field, no study has yet been carried out to analyze how residents have reacted and accepted the restrictions and security measures imposed by their national governments and their impact on residents’ feelings and perceptions, daily lives and travel plans. Furthermore, the specific impacts of this crisis will have on the younger generations are yet to be analyzed.