bluuebunny/crossref_metadata_2025_split huggingface dataset:
Membrane thickness, lipid phase and sterol type are determining factors in the permeability of membranes to small solutes
Authors: Frallicciardi Jacopo , Melcr Josef , Siginou Pareskevi , Marrink Siewert J. , Poolman Bert 
Published: July 2021

AbstractCell membranes provide a selective semi-permeable barrier to the passive transport of molecules. This property differs greatly between organisms. While the cytoplasmic membrane of bacterial cells is highly permeable for weak acids and glycerol, yeasts can maintain large concentration gradients. Here we show that such differences can arise from the physical state of the plasma membrane. By combining stopped-flow kinetic measurements with molecular dynamics simulations, we performed a systematic analysis of the permeability through synthetic lipid membranes to obtain detailed molecular insight into the permeation mechanisms. While membrane thickness is an important parameter for the permeability through fluid membranes, the largest differences occur when the membranes transit from the liquid-disordered to liquid-ordered and/or to gel state. By comparing our results with in vivo measurements from yeast, we conclude that the yeast membrane exists in a highly ordered and rigid state, which is comparable to synthetic saturated DPPC-sterol membranes.
Climatic niche pre-adaptation in mainland Europe facilitated the colonization of Madeira by ivies (Hedera L., Araliaceae)
Authors: Alonso Alejandro , Gallego-Narbón Angélica , de la Iglesia Marina Coca , Monjas David , Medina Nagore G. , Fernández-Mazuecos Mario , Valcárcel Virginia 
Published: July 2021

AbstractBackground and aimsThe way plants cope with biotic and abiotic selective pressures determines their success in the colonization of remote oceanic islands, which ultimately depends on the phylogenetic constrains and ecological response of the lineage. In this study we aim to evaluate the relative role of geographical and ecological forces in the origin and evolution of the Madeiran ivy (H. maderensis).MethodsTo determine the phylogenetic placement of H. maderensis within the western polyploid clade of Hedera (three species), we analysed 40 populations (92 individuals) using genotyping-by-sequencing and including H. helix as outgroup. Climatic niche differences among the four study species were evaluated using a database with 706 records representing the entire species ranges. To test species responses to climate, a set of 19 vegetative and regenerative functional traits were examined for 70 populations (335 individuals).Key resultsPhylogenomic results revealed a nested pattern with H. maderensis embedded within H. iberica. Gradual niche differentiation from the coldest and most continental populations of H. iberica to the warm and stable coastal population sister to H. maderensis parallels the geographical pattern observed in the phylogeny. Similarity in adaptive traits is observed for H. maderensis and H. iberica. The two species show leaves with higher SLA, lower LDMC and thickness and smaller fruits than those of H. hibernica.ConclusionsAcquisition of the Macaronesian climatic niche and the associated functional syndrome in mainland European ivies (small fruits, leaves high SLA, and low LDMD and thickness) was a key step in the colonization of Madeira by the H. iberica/H. maderensis lineage, which points to climatic pre-adaptation as a driver of island colonization (dispersal and establishment). Once in Madeira, speciation was driven by geographical isolation, while ecological processes are regarded as secondary forces with a putative impact in the lack of further in situ diversification.
Genome-wide characterization of the MLO gene family in Cannabis sativa reveals two genes as strong candidates for powdery mildew susceptibility
Authors: Pépin Noémi , Hebert Francois Olivier , Joly David L. 
Published: July 2021

AbstractCannabis sativa is increasingly being grown around the world for medicinal, industrial, and recreational purposes. As in all cultivated plants, cannabis is exposed to a wide range of pathogens, including powdery mildew (PM). This fungal disease stresses cannabis plants and reduces flower bud quality, resulting in significant economic losses for licensed producers. The Mildew Locus O (MLO) gene family encodes plant-specific proteins distributed among conserved clades, of which clades IV and V are known to be involved in susceptibility to PM in monocots and dicots, respectively. In several studies, the inactivation of those genes resulted in durable resistance to the disease. In this study, we identified and characterized the MLO gene family members in five different cannabis genomes. Fifteen Cannabis sativa MLO (CsMLO) genes were manually curated in cannabis, with numbers varying between 14, 17, 19, 18, and 18 for CBDRx, Jamaican Lion female, Jamaican Lion male, Purple Kush, and Finola, respectively (when considering paralogs and incomplete genes). Further analysis of the CsMLO genes and their deduced protein sequences revealed that many characteristics of the gene family, such as the presence of 7 transmembrane domains, the MLO functional domain, and particular amino acid positions, were present and well conserved. Phylogenetic analysis of the MLO protein sequences from all five cannabis genomes and other plant species indicated seven distinct clades (I through VII), as reported in other crops. Expression analysis revealed that the CsMLOs from clade V, CsMLO1 and CsMLO4, were significantly upregulated following Golovinomyces ambrosiae infection, providing preliminary evidence that they could be involved in PM susceptibility. Finally, the examination of variation within CsMLO1 and CsMLO4 in 32 cannabis cultivars revealed several amino acid changes, which could affect their function. Altogether, cannabis MLO genes were identified and characterized, among which candidates potentially involved in PM susceptibility were noted. The results of this study will lay the foundation for further investigations, such as the functional characterization of clade V MLOs as well as the potential impact of the amino acid changes reported. Those will be useful for breeding purposes in order to develop resistant cultivars.
Abortion occurs during double fertilisation and ovule development inPaeonia ludlowii
Authors: Chen Ting-qiao , Xie Meng-yu , Jiang Yu-meng , Yuan Tao 
Published: July 2021

AbstractPaeonia ludlowii(Stern & G.Taylor) D.Y.Hong, a rare and endangered species, is indigenous to Tibet, China and propagated only by seed. Its natural reproduction is constrained by low fecundity. Excess seed abortion is a key factor restricting its natural reproduction, cultivation, introduction, and protection. In this study, we examined the characteristics of aborted ovules, developmental differences after flowering of normal and aborted ovules, and their ratios at different positions inP. ludlowiiovary. During pollination, fertilisation, and seed development, ovule abortion was frequent, with a random abortion position. There were four types of abortion, namely, abnormal pistil, sterile ovules, abnormal embryo sac, embryo and endosperm abortions. Of these, embryo and endosperm abortions could be divided into early abortion, middle abortion, and late abortion. The early aborted ovules stopped growing on day 12, the endoblast and endosperm in the embryo sac aborted gradually. Furthermore, the shape of the embryo sac cavity changed. The volume of aborted ovules was significantly different from that of fertile ovules. At ripening, the external morphology of different types of aborted seeds was significantly different.Summary statementElucidation of the origin and characteristics of ovule abortion in an endangered Chinese plant species,Paeonia ludlowii.
The dynamic network connectedness and hedging strategies across stock markets and commodities: COVID-19 pandemic effect
Authors: Mezghani Taicir , Ben Hamadou Fatma , Boujelbène Abbes Mouna 
Published: July 2021

PurposeThe aim of this study was to investigate the dynamic network connectedness between stock markets and commodity futures and its implications on hedging strategies. Specifically, the authors studied the impact of the 2014 oil price drop and coronavirus disease 2019 (COVID-19) pandemic on risk spillovers and portfolio allocation among stock markets (United States (SP500), China (SSEC), Japan (Nikkei 225), France (CAC40) and Germany (DAX)) and commodities (oil and gold).Design/methodology/approachIn this study, the authors used the Baba, Engle, Kraft and Kroner–generalized autoregressive conditional heteroskedasticity (BEKK–GARCH) model to estimate shock transmission among the five financial markets and the two commodities. The authors rely on Diebold and Yılmaz (2014, 2015) methodology to construct network-associated measures.FindingsRelying on the BEKK–GARCH, the authors found that the recent health crisis of COVID-19 intensified the volatility spillovers among stock markets and commodities. Using the dynamic network connectedness, the authors showed that at the 2014 oil price drop and the COVID-19 pandemic shock, the Nikkei225 moderated the transmission of volatility to the majority of markets. During the COVID-19 pandemic, the commodity markets are a net receiver of volatility shocks from stock markets. In addition, the SP500 stock market dominates the network connectedness dynamic during the COVID-19 pandemic, while DAX index is the weakest risk transmitter. Regarding the portfolio allocation and hedging strategies, the study showed that the oil market is the most vulnerable and risky as it was heavily affected by the two crises. The results show that gold is a hedging tool during turmoil periods.Originality/valueThis study contributes to knowledge in this area by improving our understanding of the influence of fluctuations in oil prices on the dynamics of the volatility connection between stock markets and commodities during the COVID-19 pandemic shock. The study’s findings provide more implications regarding portfolio management and hedging strategies that could help investors optimize their portfolios.
Value creation in mobile social media: a systematic review and agenda for future research
Authors: Ju Xingting , Chocarro Raquel , Martín Martín Oscar 
Published: July 2021

PurposeThe purpose of this study is to provide a systematic review of the current state of research regarding mobile social media use for value creation by firms and customers and an agenda for future research.Design/methodology/approachThe authors conducted a systematic review following three main steps: keyword search, study selection and data extraction. A total of 53 articles were identified using academic databases and manual cross-referencing. By means of a thematic analysis method, the study addresses issues related to theory, methods, context, findings and gaps.FindingsThe study reviews and illustrates 14 value aspects of the mobile social media and value creation literature. The findings indicate that mobile social media are effective tools for firms to create and capture value from customers and for customers to co-create value.Originality/valueThe study contributes to the marketing and social media literature by proposing a conceptual framework that integrates the core components of value creation by firms and customers in the mobile social media context and by proposing an agenda for future research.
Residents’ attitudes toward tourism development at Al-Juhfa, Saudi Arabia
Authors: Algassim Ali Ahmad , Saufi Akhmad , Diswandi Diswandi , Scott Noel 
Published: July 2021

Purpose
Al-Juhfa is a small village located near Rabigh City, between Makkah and Madinah, Saudi Arabia, with significant archaeological and religious resources. The purpose of this paper is to examine residents’ attitudes toward tourism development at Al-Juhfa.

Design/methodology/approach
The qualitative study uses purposive interviewing to recruit informants. Data was collected using semi-structured interview and open-ended questions. Eight semi-structured interviews were made and a list of open-ended questions was distributed to 134 informants. All data were analysed and no new codes were found after the answer of the first 49 informants analysed.

Findings
The results show that residents’ attitudes toward tourism development in general were positive with residents expecting to receive economic, social and environmental benefits. Residents were aware of potential positive and negative impacts of tourism development and appeared to balance these in developing their attitudes. Tourism was seen to empower residents and the religiosity of the community influenced their perception of tourism development.

Originality/value
This study contributes to the literature by supporting the use of social exchange theory in this context and by recommending the inclusion of religiosity in further studies.
COVID-19 and health inequality: the nexus of race, income and mortality in New York City
Authors: Khayat Farzaneh , Teron Lemir , Rasoulyan Farzin 
Published: July 2021

Purpose
The purpose of this paper is to evaluate socioeconomic factors related to COVID-19 mortality rates in New York City (NYC) to understand the connections between socioeconomic variables, including race and income and the disease.

Design/methodology/approach
Using multivariable negative binomial regression, the association between health and mortality disparities related to COVID-19 and socioeconomic conditions is evaluated. The authors obtained ZIP code-level data from the NYC Department of Health and Mental Hygiene and the US Census Bureau.

Findings
This study concludes that the mortality rate rises in areas with a higher proportion of Hispanic and Black residents, whereas areas with higher income rates had lower mortality associated with COVID-19, among over 18,000 confirmed deaths in NYC.

Originality/value
The paper highlights the impacts of social, racial and wealth disparities in mortality rates. It brings to focus the importance of targeted policies regarding these disparities to alleviate health inequality among marginalized communities and to reduce disease mortality.
Enhancement of network coding in wireless sensor network using improved lion algorithm: intention toward maximizing network throughput and lifetime
Authors: Dike Prashant R. , Vishwanath T.S. , Rohakale Vandana 
Published: July 2021

PurposeSince communication usually accounts as the foremost problem for power consumption, there are some approaches, such as topology control and network coding (NC), for diminishing the activity of sensors’ transceivers. If such approaches are employed simultaneously, then the overall performance does raise as expected. In a wireless sensor network (WSN), the linear NC has been shown to enhance the performance of network throughput and reduce delay. However, the NC condition of existing NC-aware routings may experience the issue of false-coding effect in some scenarios and usually neglect node energy, which highly affects the energy efficiency performance. The purpose of this paper is to propose a new NC scheduling in a WSN with the intention of maximizing the throughput and minimizing the energy consumption of the network.Design/methodology/approachThe improved meta-heuristic algorithm called the improved mutation-based lion algorithm (IM-LA) is used to solve the problem of NC scheduling in a WSN. The main intention of implementing improved optimization is to maximize the throughput and minimize the energy consumption of the network during the transmission from the source to the destination node. The parameters like topology and time slots are taken for optimizing in order to obtain the concerned objective function. While solving the current optimization problem, it has considered a few constraints like timeshare constraint, data-flow constraint and domain constraint. Thus, the network performance is proved to be enhanced by the proposed model when compared to the conventional model.FindingsWhen 20 nodes are fixed for the convergence analysis, performed in terms of multi-objective function, it is noted that during the 400th iteration, the proposed IM-LA was 10.34, 13.91 and 50% better than gray wolf algorithm (GWO), firefly algorithm (FF) and particle swarm optimization (PSO), respectively, and same as LA. Therefore, it is concluded that the proposed IM-LA performs extremely better than other conventional methods in minimizing the cost function, and hence, the optimal scheduling of nodes in a WSN in terms of the multi-objective function, i.e. minimizing energy consumption and maximizing throughput using NC has been successfully done.Originality/valueThis paper adopts the latest optimization algorithm called IM-LA, which is used to solve the problem of network coding scheduling in a WSN. This is the first work that utilizes IM-LA for optimal network coding in a WSN.
Executive directors' pay-performance link and board diversity: evidence from high free cash flow and low-growth firms
Authors: Tee Chwee Ming 
Published: July 2021

PurposeThe purpose of this study is to examine whether board diversity can attenuate weaker executive directors' pay-performance link in high free cash flow and low-growth firms (HFCF_LGRW).Design/methodology/approachThis study employed the Malaysian dataset from 2005 till 2016 and the fixed-effect model to investigate the developed hypotheses. The two-stage least squares method (2SLS) is employed to mitigate endogeneity issues.FindingsThis study finds that a positive association between executive directors' pay and firm performance is weaker in HFCF_LGRW firms. However, board diversity, namely ethnic and gender diversity, can mitigate weaker executive directors' pay-performance link, indicating effective monitoring.Originality/valueThis study is among the first to reveal that executive directors' pay-performance link is weaker in firms with HFCF_LGRW growth, consistent with Jensen's (1986) free cash flow hypothesis. However, findings suggest that this agency problem in HFCF_LGRW firms is attenuated by board diversity, namely ethnic and gender diversity. This supports the notion that diversity in corporate boards serves as an effective internal monitor.
Measuring tourist behavioral intentions after the first outbreak of COVID-19 pandemic crisis. Prima facie evidence from the Greek market
Authors: Poulaki Ioulia , Nikas Ioannis A. 
Published: July 2021

Purpose
COVID-19 pandemic crisis has led the scientific community in continuous efforts to estimate its impact on tourism. UNWTO predictions indicated a decline in international tourist arrivals and the respective loss in revenues generated by tourist activity for the first year of the pandemic. Undoubtedly, such an impact may not be the same for every country, especially on a domestic level. In fact, the recovery process upon COVID-19 suggests domestic tourism as the driving force. Therefore, this paper aims to investigate the tourist behavioral intentions after the first outbreak of COVID-19 with evidence from the Greek market.

Design/methodology/approach
A primary survey with questionnaires distributed via online channels (email and social media) has been undertaken to focus on the travelers’ preferences when it comes to the main parts that compose the holiday travel (destination, transport mode, accommodation type). Additionally, there were questions regard to their perceptions on the international norms of health protection against the virus.

Findings
The results of the survey illustrate some prima facie evidence of tourist behavioral intentions of Greeks, upon a statistical analysis, which indicates preference in domestic tourism and personalized services, issues related with travel costs and health safety awareness, toward tourism recovery process and customers’ reengagement and trust to the tourism businesses and destinations.

Originality/value
As Greece is a popular destination that includes a plethora of tourism cities, this paper illustrates the intentions of Greeks toward tourism activity upon pandemic crisis, when it comes to their travel preferences, as well as their perceptions on health and safety protocols applied in destinations and tourism businesses.
Does social media usage evoke employees' spirituality? A cross-level moderation model of inclusive leadership
Authors: Zhou Fei , Mou Jian 
Published: July 2021

PurposeThe purpose of this study is to investigate the impact of social media usage (SMU) and relational energy on employees' workplace spirituality within an organization from a psychological perspective.Design/methodology/approachThis study proposes a research model based on self-determination theory. This research model was tested using a cross-level hierarchical regression analysis. Data were collected from 276 knowledge workers on 39 teams in 37 enterprises in China.FindingsSMU has a significant positive impact on employees' relational energy and workplace spirituality. Relational energy partially mediates the relationships of cognitive usage and social usage of social media with workplace spirituality and fully mediates the relationship between hedonic usage of social media and workplace spirituality. Inclusive leadership positively affects workplace spirituality and acts as a negative cross-level moderating variable on the relationship between hedonic usage and workplace spirituality.Practical implicationsThis work suggested that with appropriate SMU implications, enterprises might be able to integrate spirituality into human resource management practices to improve employees' meaningful life experiences within organizations.Originality/valueThe authors’ findings not only help to theoretically clarify the relationship between SMU and workplace spirituality but also enrich the relevant research on SMU in enterprises to improve employees' spiritual life within the organization.
Information technology exports and India's macro-economic indicators
Authors: Malik Manzoor Hassan 
Published: July 2021

PurposeThe aim of this paper is to make a descriptive exploratory effort to discern the role of IT exports in India's macro-economic indicators, like national income, employment and balance of payment in the post-Liberalization, Privatization and Globalization strategy in the 1990s. The paper also explores the vital historical developments of various dimensions of IT, such as its export growth, major software and services exports destinations, compositions of IT exports and domestic growth in India.Design/methodology/approachThis study is based on secondary data, which were collected from Balance of Payment Statistics Reserve Bank of India (RBI) and Handbook of Statistics on Indian Economy, National Association of Software and Service Companies (NASSCOM),rtd and Department of Electronics and Information Technology (DEITY). This study has used descriptive analysis and growth models for studying the objectives. Major IT sector dimensions, such as total output, exports revenue, domestic revenue, gross domestic product, employment and exports of the software and service industry, have been examined for the period 1991–2016.FindingsThe findings suggest that over the last 26 years, the information technology industry's economic footprint has extended by more than seven times. Over the same period, direct employment in the information technology sector increased at an average growth rate of around 17%. Software and services exports earn, on average, about three times greater than the other three major services of India's current account of the balance of payment.Originality/valueThis study focuses on originality in examining the role of IT exports in India's macro-economic indicators economic reforms of the 1990s and also explores the historical developments of various dimensions of IT exports and domestic growth in India. All the work has been done in original by the authors, and the work used has been acknowledged properly.