bluuebunny/crossref_metadata_2025 huggingface dataset:
Alfaxalone activates Human Pregnane-X Receptors with greater efficacy than Allopregnanolone: an in-vitro study with implications for neuroprotection during anesthesia
Authors: Serrao Juliet.M. , Goodchild Colin.S.
Published: September 2020

Background

Alfaxalone is a fast acting intravenous anesthetic with high therapeutic index. It is an analogue of the naturally-occurring neurosteroid, allopregnanolone which has been implicated in causing neuroprotection, neurogenesis and preservation of cognition, through activation of pregnane X receptors in the central nervous system. This study investigated whether alfaxalone can activate human pregnane X receptors (h-PXR) as effectively as allopregnanolone.

Methods

Allopregnanolone and alfaxalone were dissolved in dimethyl sulfoxide to make allopregnanolone and alfaxalone treatment solutions (serial 3-fold dilution concentration range, 50,000 – 206 nM). Activation of h-PXR by these ligand solutions compared with vehicle control was measured by an in-vitro method using human embryonic kidney cells (HEK293) expressing h-PXR hybridised and linked to the firefly luciferase gene. Ligand binding with and activation of h-PXR in those cells caused downstream changes in luciferase activity and light emission. That activity was measured as relative light units using a plate-reading luminometer, thus quantifying the changes in h-PXR activity caused by the ligand applied to the HEK293 cells. Ligand log concentration response curves were constructed to compare efficacy and potency of allopregnanolone and alfaxalone.

Results

Allopregnanolone and alfaxalone both activated the h-PXR to cause dose-related light emission by the linked firefly luciferase. Control solutions (0.1% dimethyl sulfoxide) produced low level light emissions. Equimolar concentrations of alfaxalone were more efficacious in activation of h-PXR: 50,000 nM, p = 0.0019; 16,700 nM, p = 0.0472; 5,600 nM, p = 0.0031 [Brown-Forsythe and Welch ANOVA].

Conclusions

Alfaxalone activates human-pregnane X receptors with greater efficacy compared with the endogenous ligand allopregnanolone. These results suggest that alfaxalone sedation and anesthesia may be accompanied by beneficial effects normally caused by the physiological effects of allopregnanolone, namely neuroprotection, neurogenesis, and preservation of cognition.
Genomic analysis reveals local transmission of SARS-CoV-2 in early pandemic phase in Peru
Authors: Padilla-Rojas Carlos , Vega-Chozo Karolyn , Galarza-Perez Marco , Calderon Henri Bailon , Lope-Pari Priscila , Balbuena-Torres Johanna , Neyra David Garcia , Huaringa-Nuñez Maribel , Rojas-Serrano Nancy , Caceres-Rey Omar A.
Published: September 2020

The dissemination of cases of the new SAR-COV-2 coronavirus represents a serious public health problem for Latin America and Peru. For this reason, it is important to characterize the genome of the isolates that circulate in Latin America. To characterize the complete genome of first samples of the virus circulating in Peru, we amplified seven overlapping segments of the viral genome by RT-PCR and sequenced using Miseq platform. The results indicate that the genomes of the Peruvian SARS-COV-2 samples belong to the genetic groups G and S. Likewise, a phylogenetic and MST analysis of the isolates confirm the introduction of multiple isolates from Europe and Asia that, after border closing, were transmitted locally in the capital and same regions of the country. These Peruvian samples (56%) grouped into two clusters inside G clade and share B.1.1.1 lineage. The characterization of these isolates must be considered for the use and design of diagnostic tools, and effective treatment and vaccine formulations.
New insights into nCOVID-19 binding domain and its cellular receptors
Authors: Garg Ankush , Kumar Gaurav , Sinha Sharmistha
Published: September 2020

nCOVID-19 virus makes cellular entry using its spike protein protruding out on its surface. Angiotensin converting enzyme 2 receptor has been identified as a receptor that mediates the viral entry by binding with the receptor binding motif of spike protein. In the present study, we elucidate the significance of N-terminal domain of spike protein in spike-receptor interactions. Recent clinical reports indicate a link between nCOVID-19 infections with patient comorbidities. The underlying reason behind this relationship is not clear. Using molecular docking, we study the affinity of the nCOVID-19 spike protein with cell receptors overexpressed under disease conditions. Our results suggest that certain cell receptors such as DC/L-SIGN, DPP4, IL22R and ephrin receptors could act as potential receptors for the spike protein. The receptor binding domain of nCOVID-19 is more flexible than that of SARS-COV and has a high propensity to undergo phase separation. Higher flexibility of nCOVID-19 receptor binding domain might enable it to bind multiple receptor partners. Further experimental work on the association of these receptors with spike protein may help us to explain the severity of nCOVID-19 infection in patients with comorbidities.
Understanding mobile payment continuance usage in physical store through social impact theory and trust transfer
Authors: Handarkho Yonathan Dri
Published: September 2020

Purpose

This study aimed to understand mobile payment (MP) continuance usage in physical settings from trust and social experience perspective. A theoretical model was proposed based on trust transfer and social impact to reveal the factors influencing user intention to continually use MP.

Design/methodology/approach

Structural equation modeling (SEM) analysis was used on 308 respondents from Indonesia to examine the theoretical model while principal component factor analysis and descriptive statistics were utilized for data preparation.

Findings

The findings revealed the Perceived Herd behavior had the most significant contribution to Trust formation followed by Perceived Risk and Para-social interaction while the analysis of indirect and moderating effect was also significant in enriching the result.

Originality/value

This study postulated social experience as an antecedent factor to the formation of Trust in the MP continuance usage context. Moreover, while the commonly explored direct effect was investigated, the indirect effect and moderating impact that has not been addressed adequately in previous MP studies were also analyzed and this can be considered as a contribution to the body of knowledge.
“Income vs. education” revisited – the roles of “family face” and gender in Chinese consumers' luxury consumption
Authors: Mo Tingting
Published: September 2020

Purpose

The transgenerational influence of inherited family capital on consumers' luxury consumption has been studied recently in the mature luxury market. However, little research explores this topic in the emerging luxury market. In China's Confucian culture, “family face” as part of “family inheritance” has been conceptualized as a factor driving luxury consumption. However, this hypothesis has not been empirically tested. The current research, therefore, seeks to examine the impact of economic and cultural capital on Chinese consumers' luxury consumption within the family inheritance context and the roles that face concern and gender play to reveal the particularities of a specific emerging luxury market.

Design/methodology/approach

A sample of 324 Chinese consumers was recruited in Shanghai. With the full sample, the author first assessed the effects of economic and educational capital (both personal and family sources) and face concern on luxury consumption using regression analyses. Next, the author conducted the regression analyses again by gender.

Findings

Unlike trends in the mature luxury market, Chinese consumers' educational levels do not drive their luxury consumption, and the transgenerational influence of economic and cultural capital functions as a negative factor. Influenced by the patrilineal tradition, higher levels of luxury consumption to compensate for parents' lower income and educational levels and to enhance family face are found only in the male consumer group, but not in the female group.

Originality/value

This research contributes to expanding the current understanding of emerging luxury markets and how the Confucian tradition influences Chinese consumers' luxury consumption through gender role norms.
Service quality dimensions of ride-sourcing services in Indian context
Authors: Shah Tejas R.
Published: September 2020

Purpose

This paper aims to identify the dimensions of service quality in the case of ride-sourcing services in Indian context.

Design/methodology/approach

The service quality dimensions of ride-sourcing services are identified using an exploratory factor analysis (EFA). Further, the reliability and validity of the factors are established through confirmatory factor analysis (CFA) using AMOS.

Findings

The service quality dimensions of ride-sourcing services are identified: comfort, internal environment, safety and personnel, mobile convenience and reliability, mobile system efficiency and availability, mobile customer service and billing and mobile security and privacy.

Research limitations/implications

The various dimensions are identified to measure service quality of ride-sourcing services in India. So, these dimensions can be tested for ride-sourcing services of countries having similar culture as India.

Practical implications

The proposed dimensions can be used as a diagnostic tool to identify and compare important criteria for service quality of ride-sourcing services.

Originality/value

Most relevant studies about dimensions of service quality for ride-sourcing services do not have stable factor structure. The dimensions identified include the traditional taxi service quality and mobile app service quality, which are not covered in current literature.
Greenko Plc1
Authors: Sinha Sidharth
Published: September 2020

Greenko, a renewable power generating company investing in biomass, small and medium hydro power and wind power projects, had projected to achieve 1GW (Giga Watt = 1000 Mega Watt) of installed capacity by March 2015. The company had been financing its projects with debt from Indian banks and financial institutions on a project finance basis and it had to now decide whether to refinance the project finance debt with an international bond issue of USD 550 million. The case provides an opportunity to discuss the public policy and financing aspects of renewable energy in India.
An emotion-based segmentation of bank service customers
Authors: Calvo-Porral Cristina , Lévy-Mangin Jean-Pierre
Published: September 2020

Purpose

Emotional and affective responses are experienced during service use that determine customer behavior; and for this reason, bank services require an better understanding of the emotions customers feel in service experiences. This research aims to examine whether different customer segments exist in the bank services industry, based on the emotions they experience when using the service.

Design/methodology/approach

The factors were examined through confirmatory factor analysis (CFA). Then, two-step clustering analysis was developed for customer segmentation on data from 451 bank service customers. Finally, an Anova test was conducted to confirm the differences among the obtained customer segments.

Findings

Our findings show that the emotion-based segmentation is meaningful in terms of behavioral outcomes in bank services. Further, research findings indicate that bank service customers cannot be perceived as a homogenous group, since four customer clusters emerge from our research namely “angry complainers”, “pragmatic uninvolved”, “emotionally attached customers” and “happy satisfied customers”.

Research limitations/implications

Our findings show that the emotion-based segmentation is meaningful in terms of behavioral outcomes in bank services. Further, research findings indicate that bank service customers cannot be perceived as a homogenous group, since four customer clusters emerge from our research namely “angry complainers”, “pragmatic uninvolved”, “emotionally attached customers” and “happy satisfied customers”, being the “angry complainers” the most challenging customer group.

Originality/value

The study is the first one to specifically segment bank customers based on the emotions they experience when using the service.
The role of job involvement and career commitment between person–job fit and organizational commitment: a study of higher education sector
Authors: Jyoti Jeevan , Sharma Poonam , Kour Sumeet , Kour Harleen
Published: September 2020

Purpose

Organizations try to appoint individuals who fit in with their values and goals. Employees who do not fit in with the organization's core values and goals prefer not to stay on for a longer period of time. The present study is an attempt to explore the impact of person–job (P–J) fit on organizational commitment through job involvement and career commitment with an application of a serial multiple mediation model.

Design/methodology/approach

Data have been collected through a structured questionnaire. The population comprised the teachers, working in the higher education sector. The different constructs used have been duly validated with the help of exploratory and confirmatory factor analyses. Further data reliability and scale validity have been checked too. In order to test the serial multiple mediation model, the authors adopted a regression-based approach and bootstrapping method suggested by Hayes (2012; 2013). Accordingly, PROCESS developed by Hayes (2012) has been used.

Findings

The results revealed that job involvement and career commitment mediate the relationship between P–J fit and organizational commitment individually as well as together.

Research limitations/implications

The present study is confined to government degree colleges only. The element of subjectivity might not have been checked completely as teachers have responded on the basis of their own experience and perceptions regarding the items in the questionnaire. The study is cross sectional in nature.

Practical implications

The paper addresses the interest of wide spectrum of stakeholders including the management, organizations and employees. So, the authors have extended general implications, which are for all those organizations that want to improve person–organization (P–O) fit and commitment of their employees. These implications will help organizations to take specific initiatives to improve the P–J fit of their employees, which will subsequently enhance their commitment level.

Originality/value

The findings of the present study will help the stakeholders in the higher education sector to identify best employees and undertake the initiatives to generate better job involvement and commitment, which will be a win–win strategy for both (employees as well as the organizations).
Robust facility location decisions for resilient sustainable supply chain performance in the face of disruptions
Authors: Sundarakani Balan , Pereira Vijay , Ishizaka Alessio
Published: September 2020

Purpose

Facility location and re-location decisions are critical managerial decisions in modern supply chains. Such decisions are difficult in this environment as managers encounter uncertainty and risks. The study investigates establishing or moving distribution facilities in the global supply chain by considering costs, fulfilment, trade uncertainties, risks under environmental trade-offs and disruptive technologies.

Design/methodology/approach

This paper combines the possibilities and probabilistic scenarios for a supply chain network by proposing the novel Robust Optimisation and Mixed Integer Linear Programming (ROMILP) method developed under the potential uncertainty of demand while considering the costs associated with a four-tier supply chain network. ROMILP has been solved in a real-time logistics environment by applying a case study approach.

Findings

The solution is obtained using an exact solution approach and provides optimality in all tested market scenarios along the proposed global logistics corridor. A sensitivity analysis examines potential facility location scenarios in a global supply chain context.

Research limitations/implications

Logistics managers can apply the ROMILP model to test the cost-benefit trade-offs against their facility location and relocation decisions while operating under uncertainty. Future research is proposed to extend the literature by applying data from the OBOR logistics corridor.

Originality/value

This study is the first to examine sustainable dimensions along the global logistics corridor and investigate the global container traffic perspective. The study also adds value to the Middle East logistics corridor regarding facility location decisions.
The safety of IoT-enabled system in smart cities of India: do ethics matter?
Authors: Chatterjee Sheshadri
Published: September 2020

Purpose

The purpose of this study is to analyze the impact of ethics and technology towards safety of internet of things (IoT)-enabled system in smart cities of India (SCI).

Design/methodology/approach

The determinants that would impact on securing IoT-enabled system in SCI have been identified by the studies of literature. Some hypothesis has been formulated. A conceptual model has been developed. Hypotheses and conceptual models have been tested by a statistical approach through survey works considering the feedbacks of 331 usable respondents. The results have been discussed followed by explaining the implications of this study. A comprehensive conclusion has been provided at the end.

Findings

The validated results show that the trust factor has insignificant impacts on the system and technology use, as well as on the behavioural intention. The model provided could achieve 79% explanative power.

Practical implications

For ensuring safety and security of IoT-enabled devices in SCI, the ethical sense of the stakeholders of SCI has considerable impact on securing safety of IoT-enabled devices in SCI. The practitioner should, as such, be sincere to motivate the stakeholders to ameliorate the ethical sense of the stakeholders for securing safety of IoT-enabled devices in SCI.

Originality/value

A few studies in the areas of Indian smart cities, IoT and related ethical issues have been conducted. In that sense, this approach is deemed to be a novel attempt.
The role of integrated offline/online social activity and social identification in Facebook citizenship behaviour formation
Authors: Bhatti Zeeshan Ahmed , Arain Ghulam Ali , Yasin Hina Mahboob , Khan Muhammad Asif , Akram Muhammad Shakaib
Published: September 2020

Purpose

Drawing on social identity theory and prosocial behaviour research, this study explores how people's integration of their offline and online social activities through Facebook cultivates their Facebook citizenship behaviour (FCB). It also offers further insight into the underlying mechanism of offline and online social activity integration - FCB relation by investigating people's social identification with their offline and online social groups as possible mediators.

Design/methodology/approach

Based on social identity theory (SIT) literature, community citizenship behaviour and offline-online social activity integration through Facebook, we developed a conceptual model, which was empirically tested using data from 308 Facebook users

Findings

The results confirm that the participants' offline-online social activity integration via Facebook is positively linked to their FCB. Further, the integration of offline and online social activity through Facebook positively affects how a person identifies with their offline and online social groups, which in turn causes them to display FCB. In addition, offline/online social identification mediates the integration – FCB relation.

Practical implications

In practice, it is interesting to see people's tendency towards altruistic behaviours within groups they like to associate themselves with. Those who share their Facebook network with their offline friends can use such network to seek help and support.

Originality/value

From a theoretical perspective, unlike past research, this study examines how individuals' offline-online social activity integration via Facebook helps them associate with groups. In addition, this study investigates social identification from an offline and online perspective.
Leadership and administrative support for interprofessional collaboration in a cancer center
Authors: Moilanen Tanja , Leino-Kilpi Helena , Kuusisto Hannele , Rautava Päivi , Seppänen Laura , Siekkinen Mervi , Sulosaari Virpi , Vahlberg Tero , Stolt Minna
Published: September 2020

Purpose

The interprofessional collaboration is a key practice for providing cancer care. However, the realization of collaboration requires effective leadership and administrative support. In this study, the aim was to analyze healthcare professionals' perceptions of leadership and administrative support (strategic and management) in interprofessional collaboration for developing practices in cancer care.

Design/methodology/approach

A descriptive survey design was used to collect data from healthcare professionals (n = 350, response rate 33.3%), including nurses, physicians and other professionals participating in patient care in one Finnish cancer center (out of five) in 05/2018–10/2018. The data were analyzed using descriptive and inferential statistics. The instrument focused on leadership in the work unit and administrative support including organization strategy and organizational management.

Findings

Healthcare professionals perceived leadership in the work unit, organization strategy and management for the support of interprofessional collaboration as weak. However, the ratings of male respondents and those in leading positions were more positive. The findings indicate that healthcare professionals in the cancer care setting are dissatisfied with the leadership and administrative support.

Research limitations/implications

Interprofessional collaboration, including its leadership, requires systematic and constant evaluation and development.

Originality/value

Healthcare leaders in the cancer care setting can use the results to identify factors that might be in need of attention and development in the field of interprofessional collaboration.
Exploring visit intention to India for medical tourism using an extended theory of planned behaviour
Authors: Dash Ajitabh
Published: September 2020

Purpose

The purpose of this paper is to identify the factors influencing the visit intention of medical tourists to India. This study also attempts to extend the theory of planned behaviour through the integration of perceived risk and facilitating condition.

Design/methodology/approach

Primary data were collected from a sample of 326 medical tourists arriving in India through Terminal-3 of Indira Gandhi International Airport (IGI-T3), New Delhi, India, during the months of October–December 2019. Confirmatory factor analysis and structural equation modelling are deployed to analyze the collected data and validate the proposed research model.

Findings

The outputs of this study revealed that perceived financial risk, physical risk, psychological risk and facilitating conditions available in a country are significantly linked to the attitude of a medical tourist. Similarly, facilitating conditions available in a country are significantly related to perceived behavioural control of a medical tourist. Furthermore, it is also revealed that attitude, subjective norm and perceived behavioural control are significantly related to visit intention of medical tourists to India; however, the perceived time risk and performance risk are insignificantly associated with the visit intention.

Research limitations/implications

This study is restricted to the opinion of 326 sample respondents consisting of medical tourists who arrived in India through IGI-T3, New Delhi, during October–December 2019. In the future, a similar type of study may be conducted in different parts of the country with a relatively larger sample size

Originality/value

This study addresses the need for advancing the knowledge on the factors in determining visit intention of medical tourists towards India. This knowledge will become very crucial for India's medical tourism industry, which is aiming to attain a competitive edge in the global market.
The dividend signaling hypothesis and the corporate life cycle
Authors: Meza Narcisa , Báez Anibal , Rodriguez Javier , Toledo Wilfredo
Published: September 2020

Purpose

This paper aims to examine the relationship between the dividend signaling hypothesis and a firm's life cycle.

Design/methodology/approach

The authors use Dickinson's (2011) methodology to develop a proxy for the firm's stages in its life cycle and to examine the relationship between dividends and future earnings following a nonlinear setting.

Findings

Using a sample of US firms during the 2000–2014 period, the authors find that the signaling hypothesis can be dependent on firm-specific characteristics, such as life cycle stages. The authors report that the relationship between dividend changes and subsequent earnings changes is different for different life stages. They also find that changes in the amount of the dividend provide some information about future earnings, especially during the early (introductory and growth) stages. These results are consistent with the use of earnings or return on assets as the dependent variables in models of earnings expectations.

Originality/value

The authors believe that this is the first time that the dividend signaling hypothesis has been linked to the life cycle of the firm.
Corporate social responsibility and organizational commitment: effects of CSR attitude, organizational trust and identification
Authors: George Nimmy A. , Aboobaker Nimitha , Edward Manoj
Published: September 2020

Purpose

Drawing from the social identity theory and social exchange theory, the purpose of this study is to examine the intervening mechanisms linking perceived corporate social responsibility (CSR) and employees’ affective organizational commitment. It is proposed that organizational trust (OT) and organizational identification (OID) would serially mediate the aforementioned relationship. Furthermore, this paper attempts to understand how employees’ attitude toward the importance of CSR (ICSR), moderates the linkages under the focus of this study.

Design/methodology/approach

This descriptive study was conducted among a sample of 519 employees working in the manufacturing sector in India. Self-reporting standardized questionnaires were administered among the respondents, who were selected through the judgment sampling method. Measurement model analysis was done using IBM AMOS 24.0 and Hayes’ PROCESS macro 3.0 (Models 6 and 84) was used for testing the serial mediation and moderated serial mediation.

Findings

Results revealed a significant indirect effect of all dimensions of CSR on employees’ affective commitment, serially mediated through OT and OID. The conditional indirect effects varied significantly and it was identified that CSR to customers and CSR to employees had a significant conditional indirect effect on affective commitment, through attitude toward the ICSR, OID and OT. However, the conditional indirect effect of CSR to social and non-social stakeholders on affective commitment was not statistically significant.

Originality/value

This study is pioneering in conceptualizing and empirically testing an integrated theoretical framework that models the influences of perceived CSR, employees’ attitude toward the ICSR, OID and OT on their affective commitment toward the organization. CSR plays a vital role in strengthening the employer-employee relationship and managers should facilitate a work environment that befits the alignment of organizational and individual ethics and values.
Providing strategic leadership for learning: optimizing managerial coaching to build learning organizations
Authors: Ellinger Andrea D. , Ellinger Alexander E.
Published: September 2020

Purpose

The purpose of this paper and the contribution to this special issue is to build on Kim and Watkins’ (2018) recent finding that ‘leaders mentor and coach those they lead’ is the item in the Dimensions of the Learning Organization Questionnaire (DLOQ) that is most highly-correlated with performance. Given the criticality of providing strategic leadership for learning and, more specifically, the consistent associations between leaders who mentor and coach and work-related performance outcomes, a better understanding of the associations between the learning organization concept and managerial coaching is warranted. Watkins and Kim (2018, p. 22) contend that ‘future directions for learning organization research include a search for the elusive interventions that would create a learning organization’. In response to this call for research, a research agenda for assessing managerial coaching as a learning organization (LO) intervention is proposed.

Design/methodology/approach

This conceptual paper briefly reviews literature on the learning organization and the DLOQ instrument, followed by a more in-depth review of the managerial coaching literature and suggestions for how future research could be conducted that more closely integrates these two concepts.

Findings

Existing literature suggests that to ‘provide strategic leadership for learning’, a dimension in the DLOQ, is one of the most pivotal dimensions for creating learning cultures that build learning organizations. Specifically, an item within this dimension, ‘leaders who mentor and coach’ has been recently identified as one of the most critical aspects associated with strategic leadership for learning.

Originality/value

The extant managerial coaching literature offers a solid foundation for more closely integrating and mainstreaming the developmental intervention of managerial coaching into learning organizations. Directions for future research that identifies fine-grained perspectives of the discrete facets of managerial coaching in learning organization contexts are suggested.
A New Approach to Compute Natural Frequencies and Mode Shapes of One-Dimensional Continuous Structures With Arbitrary Nonuniformities
Authors: Sinha Alok
Published: September 2020

One-dimensional continuous structures include longitudinal vibration of bars, torsional vibration of circular shafts, and transverse vibration of beams. Using the linear time-varying system theory, algorithms are developed in this paper to compute natural frequencies and mode shapes of these structures with nonuniform spatial parameters (mass distributions, material properties and cross-sectional areas) which can have jump discontinuities. A general numerical approach has been presented to include Dirac-delta functions and their spatial derivatives due to jump discontinuities. Numerical results are presented to illustrate the application of these techniques to the solution of different types of spatial variations of parameters and boundary conditions.
Dynamic Analysis of Power Transmission Lines With Ice-Shedding Using an Efficient Absolute Nodal Coordinate Beam Formulation
Authors: Fan Wei , Ren Hui , Zhu Weidong , Zhu Hao
Published: September 2020

Dynamic analysis of power transmission lines with ice-shedding is conducted in this work. The power transmission line is first simplified as a uniform slender round beam. While the beam can have large displacements, rotations, and deformations, its strains are assumed to be small. The bending stiffness of the transmission line is considered here, but its shear and torsion effects are neglected. An efficient absolute nodal coordinate beam formulation is developed based on the above assumptions, and the number of generalized coordinates of each element of the beam is reduced to the least. The mass matrix is constant and the generalized elastic force is evaluated by constant stiffness tensors and generalized coordinates; hence, the current formulation is very efficient. Dynamic responses of power transmission lines with ice-shedding are then calculated. A benchmark planar two-span line is first considered, and the results are validated by the commercial finite element software abaqus. By examining strain states of the transmission line, it is found that its bending stiffness cannot be neglected in this dynamic analysis. Dynamic analysis of a three-dimensional three-span line is then conducted, where towers are not in a straight line and elevation differences between adjacent towers are considered. Several cases with common ice detachment mechanisms are considered, and dynamic responses of the cable and reaction forces of insulators due to ice-shedding are analyzed.
Stability and Hopf Bifurcation of Nearest-Neighbor Coupled Neural Networks With Delays
Authors: Wang Lu , Xiao Min , Zhou Shuai , Song Yurong , Cao Jinde
Published: September 2020

In this paper, a high-dimensional system of nearest-neighbor coupled neural networks with multiple delays is proposed. Nowadays, most present researches about neural networks have studied the connection between adjacent nodes. However, in practical applications, neural networks are extremely complicated. This paper further considers that there are still connection relationships between nonadjacent nodes, which reflect the intrinsic characteristics of neural networks more accurately because of the complexity of its topology. The influences of multiple delays on the local stability and Hopf bifurcation of the system are explored by selecting the sum of delays as bifurcation parameter and discussing the related characteristic equations. It is found that the dynamic behaviors of the system depend on the critical value of bifurcation. In addition, the conditions that ensure the stability of the system and the criteria of Hopf bifurcation are given. Finally, the correctness of the theoretical analyses is verified by numerical simulation.
Investigation of Linear Higher Harmonic Control Algorithm for Rotorcraft Vibration Reduction
Authors: Im ByeongUk , Lee ChangBae , Kee YoungJung , Shin SangJoon
Published: September 2020

A linear quadratic Gaussian (LQG) controller for active vibratory loads reduction in helicopters is proposed based on a revisited higher harmonic control (HHC) input by active trailing-edge flaps (ATEFs). Conventional individual blade control (IBC) input is redefined using N − 1/rev interblade phase lead, N/rev collective, and N + 1/rev interblade phase lag signals where 1/rev frequency modulation originates from the multiblade coordinate (MBC) transform. A Mach-scaled flap blade is designed and analyzed by the multibody dynamics analysis DYMORE. A linear time-invariant representation is identified from N/rev envelopes of the input and output responses obtained by DYMORE analysis. A matlab/simulink closed-loop control simulation is designed using the identified state-space realization. The N/rev vibratory loads are reduced up to 52% with flap deflections and the linear control results match well with the nonlinear responses obtained from DYMORE. Furthermore, the multivariable closed-loop stability estimated by the loop transfer functions using disk margin analysis reveals sufficient gain and phase margins.
Improving Endo-Myocardial Biopsy by Real-Time Spectral Tissue Sensing: A Feasibility Study
Authors: Ali Awaz , Breedveld Paul , Hendriks Benno H. W.
Published: September 2020

The aim of this research is to integrate spectral tissue sensing technology inside a cardiac bioptome for real-time measurements of tissue characteristics. Bioptome tip and handle components were designed and manufactured to house and guide optical fibers. The designed components were assembled on a cardiac bioptome together with optical fibers. A technical feasibility test was carried out to study the functionality of the instrument and the effect of the optical technology on the biopsy performance. Biopsy samples were taken from five different tissue types in a porcine heart and the resulting optical spectra were compared. Spectral tissue sensing fibers were successfully integrated inside a conventional cardiac bioptome. The integrated instrument allowed differentiation between ventricular tissue, blood, and cardiac fat tissue based on blood and fat percentage and amount of scattering. Moreover, differences between scarred and nonscarred tissue were clearly visible. A first step has been made in the use of spectral tissue sensing for the detection of different tissue structures for endo-myocardial biopsy (EMB). The instrument was able to differentiate between various tissues, as well as between healthy and diseased cardiac tissues. Future research should focus on measurements of naturally diseased cardiac tissue, repeated measurements with statistical value, and improvements to the instrument design. Having the ability to measure tissue characteristics prior to acquiring a biopsy sample will not only allow easier positioning of the bioptome at the correct location but can also prevent sampling undesired tissue or scar tissue from previous biopsies.
Estimates of Probability of Detection and Sizing of Flaws in Ultrasonic Time of Flight Diffraction Inspections for Complex Geometry Components With Grooved Surfaces
Authors: Nath S. K.
Published: September 2020

In a reliability assessment of ultrasonic time-of-flight diffraction (TOFD) inspection, probability of detection (POD) and sizing (POS) curves are developed. Experiments are performed on a complex geometry specimen with the grooved inspection surface simulating the gland seal area of a steam turbine rotor. In the reliability experiment, it is assumed and confirmed that the distribution of signal responses is normal. The effects of probe center spacing on detection and sizing are observed. The PODs developed here have a decreasing trend with flaw size which is in contrary to the generally observed increasing trend in conventional ultrasonic amplitude-based flaw sizing techniques. The reason for this decreasing POD with crack height is explained in the present study. The curves developed in this work are specific to the geometry and dimensions of the specimen with the set of notches and the probes used in the experiment. Hence, these curves can only be used under similar conditions. In TOFD inspection of similar type of complex shaped structures, e.g., turbine, the POD and POS curves developed here can be used in taking an appropriate engineering decision with respect to run, repair, or replace.
Life Cycle Prediction and Evaluation of Clutch Friction Plate Considering Wear Models and Thermal Stress
Authors: Zhu Mengyu , Liu Xintian , Kan Fuchao , You Ziyun
Published: September 2020

To predict the life of the clutch friction plate, friction characteristics of the friction plate and the steel sheet assembly are analyzed in the full life cycle. A contact model of the friction surface is built based on the micro-convex body model. Wear mathematical models of friction plate are established respectively based on the contact model and sliding friction work model. The wear results of the two models are compared and analyzed. The effect of temperature on wear is considered. Fatigue life of the friction plate is predicted by wear mathematical model according to the real working states. The accuracy of the contact model and the influence of temperature on the wear are determined through the comparative analysis of each prediction result.
Hybrid Electromagnetic Shunt Damper for Vibration Control
Authors: Paknejad Ahmad , Zhao Guoying , Chesné Simon , Deraemaeker Arnaud , Collette Christophe
Published: September 2020

It has been shown that shunting electromagnetic devices with electrical networks can be used to damp vibrations. These absorbers have however limitations that restrict the control performance, i.e., the total damping of the system and robustness versus parameter variations. On the other hand, the electromagnetic devices are widely used in active control techniques as an actuator. The major difficulty that arises in practical implementation of these techniques is the power consumption required for conditioners and control units. In this study, robust hybrid control system is designed to combine the passive electromagnetic shunt damper with an active control in order to improve the performance with low power consumption. Two different active control laws, based on an active voltage source and an active current source, are proposed and compared. The control law of the active voltage source is the direct velocity feedback. However, the control law of the active current source is a revisited direct velocity feedback. The method of maximum damping, i.e., maximizing the exponential time-decay rate of the response subjected to the external impulse forcing function, is employed to optimize the parameters of the passive and the hybrid control systems. The advantage of using the hybrid control configuration in comparison with purely active control system is also investigated in terms of the power consumption. Besides these assets, it is demonstrated that the hybrid control system can tolerate a much higher level of uncertainty than the purely passive control systems.
Multicentric Analysis of the Species Distribution and Antifungal Susceptibility of Cryptic Isolates from
Aspergillus
Section
Fumigati
Authors: Imbert S. , Normand A. C. , Cassaing S. , Gabriel F. , Kristensen L. , Bonnal C. , Lachaud L. , Costa D. , Guitard J. , Hasseine L. , Palous M. , Piarroux M. , Hendrickx M. , Piarroux R. , Fekkar A.
Published: September 2020

The antifungal susceptibility of
Aspergillus
cryptic species is poorly known. We assessed 51 isolates, belonging to seven
Fumigati
cryptic species, by the EUCAST reference method and the concentration gradient strip (CGS) method. Species-specific patterns were observed, with high MICs for azole drugs, except for
Aspergillus hiratsukae
and
Aspergillus tsurutae
, and high MICs for amphotericin B for
Aspergillus lentulus
and
Aspergillus udagawae
.
Bacillus thuringiensis Cry1Ab Domain III β-22 Mutants with Enhanced Toxicity to Spodoptera frugiperda (J. E. Smith)
Authors: Gómez Isabel , Ocelotl Josue , Sánchez Jorge , Aguilar-Medel Sotero , Peña-Chora Guadalupe , Lina-Garcia Laura , Bravo Alejandra , Soberón Mario
Published: September 2020

Spodoptera frugiperdais an important worldwide pest of maize and rice crops that has evolved resistance to Cry1Fa-expressing maize in different countries. Therefore, identification of additional toxins with different modes of action is needed to provide alternative tools to control this insect pest.Bacillus thuringiensis(Bt) Cry1Ab and Cry1Ac toxins are highly active against several important lepidopteran pests but show varying and low levels of toxicity against differentS. frugiperdapopulations. Thus, the identification of Cry1A mutants that gain toxicity toS. frugiperdaand retain toxicity to other pests could be of great value to produce transgenic crops that resist a broader spectrum of lepidopteran pests. Here, we characterized Cry1Ab domain III β-22 mutants, and we found that a Cry1AbS587A mutant displayed increased toxicity against differentS. frugiperdapopulations. Thus, Cry1AbS587A could be a good toxin candidate to produce transgenic maize with broader efficacy against this important insect pest in the field.
Live-Cell FRET Reveals that Malaria Nutrient Channel Proteins CLAG3 and RhopH2 Remain Associated throughout Their Tortuous Trafficking
Authors: Ahmad Moaz , Manzella-Lapeira Javier , Saggu Gagandeep , Ito Daisuke , Brzostowski Joseph A. , Desai Sanjay A.
Published: September 2020

Malaria parasites grow within circulating red blood cells and uptake nutrients through a pore on their host membrane. Here, we used gene editing to tag CLAG3 and RhopH2, two proteins linked to the nutrient pore, with fluorescent markers and tracked these proteins in living infected cells. After their synthesis in mature parasites, imaging showed that both proteins are packaged into membrane-bound rhoptries. When parasites ruptured their host cells and invaded new red blood cells, these proteins were detected within a vacuole around the parasite before they migrated and inserted in the surface membrane of the host cell. Using simultaneous labeling of CLAG3 and RhopH2, we determined that these proteins interact tightly during migration and after surface membrane insertion. Red blood cells infected with two parasites had twice the protein at their surface and a parallel increase in the number of nutrient pores. Our work suggests that these proteins directly facilitate parasite nutrient uptake from human plasma.
Unstable Mechanisms of Resistance to Inhibitors of Escherichia coli Lipoprotein Signal Peptidase
Authors: Pantua Homer , Skippington Elizabeth , Braun Marie-Gabrielle , Noland Cameron L. , Diao Jingyu , Peng Yutian , Gloor Susan L. , Yan Donghong , Kang Jing , Katakam Anand Kumar , Reeder Janina , Castanedo Georgette M. , Garland Keira , Komuves Laszlo , Sagolla Meredith , Austin Cary D. , Murray Jeremy , Xu Yiming , Modrusan Zora , Xu Min , Hanan Emily J. , Kapadia Sharookh B.
Published: September 2020

Despite increasing evidence suggesting that antibiotic heteroresistance can lead to treatment failure, the significance of this phenomena in the clinic is not well understood, because many clinical antibiotic susceptibility testing approaches lack the resolution needed to reliably classify heteroresistant strains. Here we present G0790, a new globomycin analog and potent inhibitor of the
Escherichia coli
type II signal peptidase LspA. We demonstrate that in addition to previously known mechanisms of resistance to LspA inhibitors, unstable genomic amplifications containing
lspA
can lead to modest yet biologically significant increases in LspA protein levels that confer a heteroresistance phenotype.
Survey of Early-Diverging Lineages of Fungi Reveals Abundant and Diverse Mycoviruses
Authors: Myers J. M. , Bonds A. E. , Clemons R. A. , Thapa N. A. , Simmons D. R. , Carter-House D. , Ortanez J. , Liu P. , Miralles-Durán A. , Desirò A. , Longcore J. E. , Bonito G. , Stajich J. E. , Spatafora J. W. , Chang Y. , Corrochano L. M. , Gryganskyi A. , Grigoriev I. V. , James T. Y.
Published: September 2020

Viruses are key drivers of evolution and ecosystem function and are increasingly recognized as symbionts of fungi. Fungi in early-diverging lineages are widespread, ecologically important, and comprise the majority of the phylogenetic diversity of the kingdom. Viruses infecting early-diverging lineages of fungi have been almost entirely unstudied. In this study, we screened fungi for viruses by two alternative approaches: a classic culture-based method and by transcriptome-mining. The results of our large-scale survey demonstrate that early-diverging lineages have higher infection rates than have been previously reported in other fungal taxa and that laboratory strains worldwide are host to infections, the implications of which are unknown. The function and diversity of mycoviruses found in these basal fungal lineages will help guide future studies into mycovirus origins and their evolutionary ramifications and ecological impacts.
Network Rewiring: Physiological Consequences of Reciprocally Exchanging the Physical Locations and Growth-Phase-Dependent Expression Patterns of the
Salmonella fis
and
dps
Genes
Authors: Bogue Marina M. , Mogre Aalap , Beckett Michael C. , Thomson Nicholas R. , Dorman Charles J.
Published: September 2020

We assessed the impact on
Salmonella
physiology of reciprocally translocating the genes encoding the Fis and Dps nucleoid-associated proteins (NAPs) and of inverting their growth-phase production patterns such that Fis was produced in stationary phase (like Dps) and Dps was produced in exponential phase (like Fis). Changes to peak binding of Fis were detected by ChIP-seq on the chromosome, as were widespread impacts on the transcriptome, especially when Fis production mimicked Dps production. Virulence gene expression and the expression of a virulence phenotype were altered. Overall, these radical changes to NAP gene expression were well tolerated, revealing the robust and well-buffered nature of global gene regulation networks in the bacterium.