bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lathosterol oxidase (sterol C5-desaturase) deletion confers resistance to amphotericin B and sensitivity to acidic stress inLeishmania major
Authors: Ning Yu , Frankfater Cheryl , Hsu Fong-Fu , Soares Rodrigo P. , Cardoso Camila A. , Nogueira Paula M. , Lander Noelia Marina , Docampo Roberto , Zhang Kai 
Published: April 2020

ABSTRACTLathosterol oxidase (LSO) catalyzes the formation of C5-C6 double bond in the synthesis of various types of sterols in mammals, fungi, plants and protozoa. InLeishmaniaparasites, mutations inLSOor other sterol biosynthetic genes are associated with amphotericin B resistance. To investigate the biological roles of sterol C5-C6 desaturation, we generated aLSO-null mutant line (lso–) inLeishmania major, the causative agent for cutaneous leishmaniasis.Lso–parasites lacked the ergostane-based sterols commonly found in wild typeL. majorand instead accumulated equivalent sterol species without the C5-C6 double bond. These mutant parasites were replicative in culture and displayed heightened resistance to amphotericin B. However, they survived poorly after reaching the maximal density and were highly vulnerable to the membrane-disrupting detergent Triton X-100. In addition,lso–mutants showed defects in regulating intracellular pH and were hypersensitive to acidic conditions. They also had potential alteration in the carbohydrate composition of lipophosphoglycan, a membrane-bound virulence factor inLeishmania. All these defects inlso–were corrected upon the restoration of LSO expression. Together, these findings suggest that the C5-C6 double bond is vital for the structure of sterol core, and while the loss of LSO can lead to amphotericin B resistance, it also makesLeishmaniaparasites vulnerable to biologically relevant stress.IMPORTANCESterols are essential membrane components in eukaryotes and sterol synthesis inhibitors can have potent effects against pathogenic fungi and trypanosomatids. Understanding the roles of sterols will facilitate the development of new drugs and counter drug resistance. Lathosterol oxidase (aka sterol C5-desaturase) is required for the formation of C5-C6 double bond in the sterol core structure in mammals, fungi, protozoans, plants and algae. Functions of this C5-C6 double bond are not well understood. In this study, we generated and characterized a lathosterol oxidase-null mutant inLeishmania major. Our data suggest that the C5-C6 double bond is vital for the structure and membrane-stabilizing functions of leishmanial sterols. In addition, our results imply that while mutations in lathosterol oxidase can confer resistance to amphotericin B, an important antifungal and antiprotozoal agent, the alteration in sterol structure leads to significant defects in stress response that could be exploited for drug development.
Model-driven experimental design identifies counter-acting feedback regulation in the osmotic stress response of yeast
Authors: Suzuki Sara Kimiko , Errede Beverly , Dohlman Henrik G. , Elston Timothy C. 
Published: April 2020

AbstractCells rely on mitogen-activated protein kinases (MAPKs) to survive environmental stress. In yeast, activation of the MAPK Hog1 is known to mediate the response to high osmotic conditions. Recent studies of Hog1 revealed that its temporal activity is subject to both negative and positive feedback regulation, yet the mechanisms of feedback remain unclear. By designing mathematical models of increasing complexity for the Hog1 MAPK cascade, we identified pathway circuitry sufficient to capture Hog1 dynamics observed in vivo. We used these models to optimize experimental designs for distinguishing potential feedback loops. Performing experiments based on these models revealed mutual inhibition between Hog1 and its phosphatases as the likely positive feedback mechanism underlying switch-like, dose-dependent MAPK activation. Importantly, our findings reveal a new signaling function for MAPK phosphatases. More broadly, they demonstrate the value using mathematical models to infer targets of feedback regulation in signaling pathways.
Leveraging immonium ions for identifying and targeting acyl-lysine modifications in proteomic datasets
Authors: Muroski John M. , Fu Janine Y. , Nyugen Hong Hanh , Ogorzalek Loo Rachel R. , Loo Joseph A. 
Published: April 2020

AbstractAcyl modifications vary greatly in terms of elemental composition and site of protein modification. Developing methods to identify these modifications more confidently can help assess the scope of these modifications in large proteomic datasets. Herein we analyze the utility of acyl-lysine immonium ions for identifying the modifications in proteomic datasets. We demonstrate that the cyclized immonium ion is a strong indicator of acyl-lysine presence when its rank or relative abundance compared to other ions within a spectrum is considered. Utilizing a stepped collision energy method in a shotgun experiment highlights the immonium ion strongly. Implementing an analysis that accounted for features within each MS2spectra, this method allows peptides with short chain acyl-lysine modifications to be clearly identified in complex lysates. Immonium ions can also be used to validate novel acyl-modifications; in this study we report the first examples of3-hydroxylpimelyl-lysine modification and validate them using immonium ions. Overall these results solidify the use of the immonium ion as a marker for acyl-lysine modifications in complex proteomic datasets.Statement of SignificanceAcyl-lysine modifications come in a variety of elemental compositions. There is increasing evidence that these modifications can have a functional effect on protein and are present in proteomes across all domains of life. Here we describe a new method that can allow for more confident identification of acyl modifications in proteomes by utilizing the immonium ion of these modifications. Our utilization of these ions allows for more comprehensive insight into the role of acyl modifications at the systems level.
Transcriptional Downregulation of a Type III Secretion System under Reducing Conditions inBordetella pertussis
Authors: Goto Masataka , Hanawa Tomoko , Abe Akio , Kuwae Asaomi 
Published: April 2020

ABSTRACTBordetella pertussisuses a type III secretion system (T3SS) to inject virulence proteins into host cells. Although theB. pertussisT3SS was presumed to be involved in host colonization, the efficient secretion of type III secreted proteins fromB. pertussishas not been observed. To investigate the roles of type III secreted proteins during infection, we attempted to optimize culture conditions for the production and secretion of a type III secreted protein, BteA, inB. pertussis. We observed thatB. pertussisefficiently secretes BteA in ascorbic acid-depleted (AsA−) medium. When L2 cells, a rat lung epithelial cell line, were infected withB. pertussiscultured in the AsA−medium, BteA-dependent cytotoxicity was observed. We also performed an immunofluorescence assay of L2 cells infected withB. pertussis. The clear fluorescence signals of Bsp22, a needle structure of T3SS, were detected on the bacterial surface ofB. pertussiscultured in the AsA−medium. Since ascorbic acid is known as a reducing agent, we culturedB. pertussisin liquid medium containing other reducing agents such as 2-mercaptoethanol and dithioerythritol. Under these reducing conditions, the production of type III secreted proteins was repressed. These results suggest that inB. pertussis, the production and secretion of type III secreted proteins are downregulated under reducing conditions.IMPORTANCEThe type III secretion system (T3SS) ofBordetella pertussisforms a needle-like structure that protrudes from the bacterial cell surface.B. pertussisuses T3SS to translocate virulence proteins called effectors into host cells. The culture conditions for effector production inB. pertussishave not been investigated. We attempted to optimize culture medium compositions for producing and secreting type III secreted proteins. We found thatB. pertussissecretes type III secreted proteins in reducing agent-deprived liquid medium, and that BteA-secretingB. pertussisprovokes cytotoxicity against cultured mammalian cells. These results suggest that redox signaling is involved in the regulation ofB. pertussisT3SS.
Information credibility and organizational feedback; a solution to plethora of consumer advocacy, brand avoidance and community usefulness
Authors: Abro Muhammad Azeem , Baharun Rohaizat , Zubair Ahsan 
Published: April 2020

Purpose
This study aims to investigate the impact of consumer advocacy on community usefulness and brand avoidance. Moreover, the study scrutinizes the mediating role and impact of organizational feedback/response and moderating role of information credibility.

Design/methodology/approach
The explanatory and cross-sectional research design was used in the study. Primary data were collected from broadband internet users and 249 responses gathered across the country. The study sample comprises of individuals sharing unfavorable service experiences on social media.

Findings
The key findings of the study highlight that consumer advocacy is a type of complaining method, which is used to help other society members; hence, there is a strong relationship among consumer’s advocacy and society’s usefulness. Brand avoidance is the outcome of stronger reactions by consumer advocates and through efficient organizational feedback, the impact of advocacy can be mitigated. Moreover, the study found that effective organizational explanations can be a useful remedy to brand avoidance. Furthermore, the research revealed that information credibility does not moderate the relationship between consumer advocacy and brand avoidance.

Practical implications
The study findings will help practitioners in determining effective strategies to restrict and control brand avoidance.

Originality/value
The social side of consumer argumentative behavior is still an under-research area, which is addressed in the paper. This is the unique study, which explores the mediating impact of organizational feedback on consumer advocacy, brand avoidance and usefulness for society in the implicit perspective.
Strategic communication practices by consultants in Colombia
Authors: Preciado-Hoyos Angela 
Published: April 2020

PurposeThe purpose of this study is to determine the perception of communication and PR agency directors in Colombia regarding strategic communication and its relationship with consultancy when involved with three types of activities: bringing the context close to the organization, providing new knowledge and facilitating change.Design/methodology/approachThis paper provides an exploratory study based on semi-structured interviews of a sample of 55 communication and PR agency directors.FindingsAmong the directors interviewed, there are different criteria concerning strategic communication and the services this entails. Although the literature mentions that consultancy should focus on counseling, accompanying, advising and orienting without making decisions for the client or performing any operative activities, many Colombian agencies offer these services, in addition to other technical ones. This is because these are the most requested ones by their clients and so are important in acquiring contracts in the country's communication sector.Research limitations/implicationsThe limitation of this study is the absence of a regularly and systematically updated directory and database with the current size of the communications sector and its yearly revenue in Colombia.Practical implicationsLack of consensus regarding strategic communication consultancy may lead to unfair competition on prices and confounding strategic and nonstrategic services in the market.Social implicationsNew academic knowledge for the communication practices in communication agencies in Colombia and Latin America.Originality/valueThis article arises from initial research done in Colombia on the perceptions of the communication sector's directors regarding the meaning of strategic communication and key capacities in the provision of services under that remit.
Computational implementation and formalism of FAIR data stewardship principles
Authors: Anjaria Kushal Ajaybhai 
Published: April 2020

PurposeThe progress of life science and social science research is contingent on effective modes of data storage, data sharing and data reproducibility. In the present digital era, data storage and data sharing play a vital role. For productive data-centric tasks, findable, accessible, interoperable and reusable (FAIR) principles have been developed as a standard convention. However, FAIR principles have specific challenges from computational implementation perspectives. The purpose of this paper is to identify the challenges related to computational implementations of FAIR principles. After identification of challenges, this paper aims to solve the identified challenges.Design/methodology/approachThis paper deploys Petri net-based formal model and Petri net algebra to implement and analyze FAIR principles. The proposed Petri net-based model, theorems and corollaries may assist computer system architects in implementing and analyzing FAIR principles.FindingsTo demonstrate the use of derived petri net-based theorems and corollaries, existing data stewardship platforms – FAIRDOM and Dataverse – have been analyzed in this paper. Moreover, a data stewardship model – “Datalection” has been developed and conversed about in the present paper. Datalection has been designed based on the petri net-based theorems and corollaries.Originality/valueThis paper aims to bridge information science and life science using the formalism of data stewardship principles. This paper not only provides new dimensions to data stewardship but also systematically analyzes two existing data stewardship platforms FAIRDOM and Dataverse.
Critical overrun causations in marine projects
Authors: Karami Hamidreza , Olatunji Oluwole Alfred 
Published: April 2020

PurposeDelay causations in infrastructure projects are well reported in normative literature. However, very little is known regarding the environment-related causations which can assist in developing mitigation strategies. This study aims to examine critical causations of overruns in marine construction projects.Design/methodology/approachA total of 73 delay factors, grouped into 16 themes, were identified from literature. Data relating to the significance of each factor were collected through a questionnaire survey administered to 151 respondents. A total number of 126 valid responses were retrieved. Reductionist methodology was used to identify the statistical significance of each delay causation.FindingsAll 73 variables analysed in the study are significant, including communication issues amongst stakeholders, inadequate planning, safety issues, deficient technical instructions and inappropriate management approaches. Others include design and construction issues, issues with project organisational structures, political and cultural factors, environmental uncertainties and complexity in resource management. The study also found estimation errors, owner's attitude, financial issues, delay in approval processes, construction strategies and unavailability of appropriate technologies for the work as influencing factors. These findings are consistent with earlier studies on other forms of projects, but they further confirm that they are very relevant to marine projects.Research limitations/implicationsDue to the diversity of marine projects, overrun factors are likely to manifest in different ways in varying project circumstances. In addition, economics, technologies and local legislation often influence project situations differently.Practical implicationsThe implications of these findings will assist in growing the practicality of scheduling and contract administration theories in marine projects. Although delay causations that have been reported in normative literature are relevant to marine construction, however, some of the causations are more severe in marine projects. It is important that planners and project stakeholders are mindful of this such that they can develop their expectations to tolerate variability rather than trade impracticable blames.Originality/valueDetermining delay factors specific to marine construction projects assists stakeholders and project management community in developing dedicated strategies applicable in scheduling to prevent and correct obstructions caused by overruns. Since projects are different in types and sizes, delay observations cannot be generalised.
Tattoos and unfavorable treatment among employees in the hospitality industry
Authors: Tews Michael J. , Stafford Kathryn 
Published: April 2020

PurposeAs employers are purportedly becoming more receptive to tattoos, the question arises whether tattooed employees are nonetheless subject to unfavorable treatment. In this light, the purpose of this paper is to examine the impact of different tattoo characteristics on four outcomes: annual earnings, fair interpersonal treatment from supervisors, perceived discrimination and perceived overqualification. The specific tattoo characteristics were tattoo number, visibility and content.Design/methodology/approachSurvey data from a sample of 162 tattooed hospitality employees were obtained from a Qualtrics research panel and analyzed using regression.FindingsThe results demonstrated that employees with a greater degree of dark tattoo content (content of a more threatening and intimidating nature) received less favorable treatment, as demonstrated by significant relationships with fair interpersonal treatment, perceived discrimination and perceived overqualification. Tattoo number was related to increased perceived discrimination and perceived overqualification. At the same time, tattoo number was related to increased annual earnings, signaling a benefit.Research limitations/implicationsMeasures of tattoo characteristics and workplace outcomes were collected in a single survey. An analysis of data collected at different points would potentially provide a more definitive test of cause and effect.Practical implicationsOn one front, organizations should establish grooming policies that specify what is acceptable with respect to tattoos. To help minimize personality-related tattoo stereotypes from influencing hiring decisions, organizations could use personality assessments to make the hiring process more objective. Moreover, diversity training could address tattoo-related stereotypes, bias and prejudice.Originality/valueEven though prior studies have demonstrated that tattooed people are viewed as less suitable for employment, research focused on the relationship between tattoos and actual discrimination has been limited. The results from this study highlight that employees with tattoos may still be subject to maltreatment, despite the mainstreaming of tattoos.
Which types of experience matter? The role of prior start-up experiences and work experience in fostering youth entrepreneurial intentions
Authors: Bignotti Alex , le Roux Ingrid 
Published: April 2020

PurposeIn spite of research on entrepreneurial intentions being a mature field of enquiry, little is known about the influence of experience on entrepreneurial intentions, especially among the youth and in developing contexts. This paper aims to investigate the impact of different types of experience – entrepreneurial early childhood experiences, prior start-up experiences, work experience, education and peer influence – on the entrepreneurial intentions of South African youth.Design/methodology/approachFirst, a quantitative survey of 827 secondary students was administered, and the results were analysed by means of hierarchical logistic regression. Second, two focus groups were conducted with secondary students representing two distinct segments of South African society to shed light on some of the unique survey findings.FindingsThe results revealed that the experiences of having attempted to start a business and having previously worked in a business, as well as entrepreneurship education, have a positive influence on youth entrepreneurial intentions, while peers' entrepreneurial intentions exert a negative influence. Peer influence and contextual factors such as family and community support, which are catalytic in other parts of the world, appear to dampen youth entrepreneurial intentions because of fear of failure and fear of competition.Originality/valueThis paper examines the influence of a broader taxonomy of experience types on youth entrepreneurial intentions than found in previous studies. It highlights the unique role played by specific types of experience and points to the need to include extra-curricular entrepreneurial experiences in interventions aimed at fostering youth entrepreneurial intentions in developing nations.
The impact of trust, privacy and quality of service on the success of E-CRM: the mediating role of customer satisfaction
Authors: Dehghanpouri Houriyeh , Soltani Zeynab , Rostamzadeh Reza 
Published: April 2020

Purpose
The purpose of this paper is to examine the effect of trust, privacy, service quality and customer satisfaction on the success of electronic customer relationship management (E-CRM) systems.

Design/methodology/approach
In this paper, a new model for determining the critical factors in the success of E-CRM systems is presented. The suggested model is verified using partial least squares with structural equation modeling. A questionnaire is designed and collected from 378 taxpayers in East Azerbaijan province of Iran.

Findings
The outcomes reveal that customer satisfaction is significantly influenced by the perceived quality of service. Customer satisfaction, in turn, is significantly impacted by the trust. Therefore, the quality of service, trust and privacy, through customer satisfaction, significantly affects the success of E-CRM systems.

Research limitations/implications
The main limitation can be referred to the clients that would not cooperate well as they were avoiding to give much information about the financial issue. Also, the study was conducted only in the context of Iran and a limit sample was utilized.

Practical implications
The research results help service providers improve E-CRM.

Originality/value
This study sheds light on identifying the antecedents of trust, privacy and quality of service that affect customer satisfaction; it may contribute to the theoretical framework for customer satisfaction in the context of the E-CRM. The results of the research offer practical implications for marketing managers and practitioners who prepare strategic plans and implement tools to improve the productivity or performance of the E-CRM systems. Moreover, customer satisfaction is related to the success of E-CRM systems as a result of trust, privacy and service quality. This research offers new insights into E-CRM intentions from a taxpayer in Iran.