bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trypanosoma brucei Mitochondrial DNA Polymerase POLIB Contains a Novel Thumb Insertion That Confers Dominant Exonuclease Activity
Authors: Delzell Stephanie B. , Nelson Scott W. , Frost Matthew P. , Klingbeil Michele M. 
Published: August 2022

ABSTRACTTrypanosoma brucei and related parasites contain an unusual catenated mitochondrial genome known as kinetoplast DNA (kDNA) composed of maxicircles and minicircles. The kDNA structure and replication mechanism are divergent and essential for parasite survival. POLIB is one of three Family A DNA polymerases independently essential to maintain the kDNA network. However, the division of labor among the paralogs, particularly which might fulfill the role of a replicative, proofreading enzyme remains enigmatic. De novo modeling of POLIB revealed a structure divergent from all other Family A polymerases in which the thumb subdomain contains a 369 amino acid insertion with homology to DEDDh DnaQ family 3’-5’ exonucleases. Here we demonstrate recombinant POLIB 3’-5’ exonuclease prefers DNA vs. RNA substrates and degrades single- and double-stranded DNA in a non-processive manner. The exonuclease activity prevails over polymerase activity on DNA substrates at pH 8.0, while DNA primer extension is favored at pH 6.0. Mutations that ablate POLIB polymerase activity slow the exonuclease rate suggesting crosstalk between the domains. We show that POLIB is able to extend an RNA primer more efficiently than a DNA primer in the presence of dNTPs but does not incorporate rNTPs efficiently using either primer. Immunoprecipitation of Pol I-like paralogs from T. brucei corroborate the pH selectivity and RNA primer preferences of POLIB and revealed that the other paralogs efficiently extend a DNA primer. The unique POLIB thumb insertion influences the balance between polymerase and exonuclease activity and provides another example of exquisite diversity among DNA polymerases for specialized function.
Mechanical compression induces persistent bacterial growth during bacteriophage predation
Authors: Mason Guy , Rojas Enrique R. 
Published: August 2022

AbstractAlthough the relationship between bacteria and lytic bacteriophage is fundamentally antagonistic, these microbes not only coexist but thrive side-by-side in myriad ecological environments. The mechanisms by which coexistence is achieved, however, are not fully understood. By examining Escherichia coli and bacteriophage T7 population dynamics at the single-cell and single-virion level using a novel microfluidics-based assay, we observed bacteria growing “persistently” when perfused with high-titer bacteriophage. Persistence occurred at a frequency five orders of magnitude higher than is expected from natural selection of bacteriophage-resistant mutants. Rather, the frequency of persistence was correlated with the degree to which the bacteria were mechanically compressed by the microfluidic perfusion chamber. Using a combination of mutagenesis and fluorescent imaging techniques, we found that compression induces persistence by activating the Rcs phosphorelay pathway, which results in the synthesis of extracellular capsule that sterically blocks bacteriophage adsorption. Other forms of mechanical stimulation also promoted Rcs activity and persistence. These findings have important implications for our understanding of microbial ecology in many important environments, including the gut and the soil, where bacteria grow in confinement.Significance StatementBacteria and bacteriophage form one of the most fundamental and important predator-prey relationships on earth, yet the factors that promote long-term stability of their populations are unknown. Here, we demonstrate that Escherichia coli is able to rapidly grow during bacteriophage predation if they are doing so in spatially confined environments. This discovery revises our understanding of bacteria-bacteriophage population dynamics in many real-world environments where bacteria grow in such environments, such as the gut and the soil. Additionally, this result has critical implications for the potential of antibacterial therapies to function during pathogenesis, when bacteria are also mechanically stimulated.
Plot-based approach for controlled morphological transformation in urban heritage contexts: the case of New Gourna village, Luxor – Egypt
Authors: AlSadaty Aliaa 
Published: August 2022

PurposeAs historic cities evolve, change in their urban form can be expected. Yet, uncontrolled change of land plots, which represent a significant element of urban form, leads to uncontrolled change in buildings' configurations and typologies threatening accordingly the urban character of heritage contexts. Mechanisms controlling plot subdivision, however, can play an effective role in guiding developments and in controlling urban change in heritage settings. The present study seeks to assist decision-makers in their attempt to control urban change in heritage areas through a plot-based approach.Design/methodology/approachThis paper is divided into three sections: the first focuses on plot subdivision as a key aspect of urban form; the second illustrates the case of the heritage village of New Gourna in Luxor and the third includes discussion and implications of adopting a plot-based morphological approach to control morphological transformation in heritage contexts. For the morphological analysis of New Gourna, the study relied on comparative cartographic analysis of original drawings of the village versus the situation in 2022. The morphological analysis focuses mainly on qualitative and quantitative aspects of plot configurations and building patterns.FindingsFindings support the urgency of establishing a plot-based strategy to maintain urban character of heritage contexts in Egypt and call for a plot-based morphological approach to control change and inform new development attempts.Originality/valueThe present research provides an assessment of the morphological transformation of the heritage village of New Gourna. In addition, it proposes a plot-based approach for heritage contexts under transformation.
System reliability analysis of foundation stability of gravity dams considering anisotropic seepage and multiple sliding surfaces
Authors: He Jia-Nan , Yang De-wei , Zhenyu Wu 
Published: August 2022

PurposeFor gravity dams built on foundations with directional joint sets, the seepage in the foundation possesses anisotropic characteristics and may have adverse effects on the foundation stability. A methodology for system reliability analysis of gravity dam foundations considering anisotropic seepage and multiple sliding surfaces is proposed in this paper.Design/methodology/approachAnisotropic seepages in dam foundations are simulated using finite element method (FEM) with the equivalent continuum model (ECM), and their effect on dam foundation stability is involved by uplift pressures acting on the potential sliding surfaces. The system failure probability of the dam foundation is efficiently estimated using Monte Carlo method (MCM) combined with response surface method (RSM).FindingsThe case study shows that it is necessary to consider the possibly adverse effect of anisotropic seepage on foundation stability of gravity dams and the deterministic analysis of the foundation stability may be misleading. The system reliability analysis of the dam foundation is justified, as the uncertainties in shear strength parameters of the foundation rocks and joint sets as well as aperture, connectivity and spacing of the joint sets are quantified and the system effect of the multiple potential sliding surfaces on the foundation reliability is reasonably considered.Originality/value(1) A methodology is proposed for efficient system reliability analysis of foundation stability of gravity dams considering anisotropic seepage and multiple sliding surfaces (2) The influence of anisotropic seepage on the stability of gravity dam foundation is revealed (3) The influence of estimation errors of RSMs on the system reliability assessment of dam foundation is investigated.
Salaam Bombay Foundation: challenges in integrating skills, education and job markets for adolescents in India
Authors: Galliara Meena , Sisodia Swati , Nagpal Pragya 
Published: August 2022

Learning outcomes
The learning outcomes are as follows: to analyze the driving forces that lead non-government organizations (NGOs) to develop need-based programs; to evaluate the strategy adopted by NGOs in attaining the organization’s mission and creating a social impact, corporate social responsibility, inclusion, labor market, social enterprise, strategy and vocational learning; to apply social business canvas for analyzing the business model deployed by NGOs to develop market linkages; to analyze the challenges in setting and scaling NGO programs and strategies designed to address the same; and to enable students to brainstorm in creating future growth options for scaling up and replicating NGO programs.

Case overview/synopsis
The case describes the journey of Salaam Bombay Foundation (SBF), a national-level NGO registered in 2002 in Mumbai, India. In March 2020, SBF had an annual budget of INR 13.98 crores (US$1.84m). It addresses the challenging environments children from economically constrained families face by engaging them in continuing school education and providing vocational training. Since its inception, SBF has launched and executed many in-school and after-school programs. To successfully transit skilled adolescents and teenagers into the labor market and help them make informed career decisions, SBF launched “DreamLab,” a stipend-based “internship” model, in August 2018. Gaurav Arora, Vice President SBF, was assigned the responsibility to scale up skills@school and DreamLab internship programs. With disruptions caused by the pandemic in March 2020, Arora struggled to operationalize DreamLab as initially planned. The case is at a crucial decision point where clouds of uncertainty have made Arora and his team anxious about their future course of action.

Complexity academic level
The case is intended for students of undergraduate and graduate programs in Business Management, Social Entrepreneurship and Social Work programs. Executives of management development programs can also use the case to analyze the effectiveness and management of the skill development program.

Supplementary materials
Teaching notes are available for educators only.

Subject code
CSS 3: Entrepreneurship.
The future of e-commerce? Understanding livestreaming commerce continuance usage
Authors: Chong Han Xi , Hashim Ahmad Hariza , Osman Syuhaily , Lau Jasmine Leby , Aw Eugene Cheng-Xi 
Published: August 2022

PurposeThe purpose of this paper is to identify the continuance usage of livestreaming commerce. The proposed antecedents of livestreaming commerce continuance usage are social presence, perceived crowdedness, need for arousal, susceptibility to informational influence, and perceived value, whilst trust in broadcasters is treated as the moderating factor.Design/methodology/approachA survey was conducted using a questionnaire designed specifically for this purpose, which was completed by 388 Malaysian consumers aged 26–40 years who have prior experience with livestreaming commerce. The authors tested the framework using the partial least squares structural equation modelling (PLS-SEM) technique and complementary by performing artificial neural network (ANN) analysis.FindingsThe results indicate several significant relationships, whereby social presence, perceived crowdedness, susceptibility to informational influence, and trust in broadcasters significantly influence perceived value, whereas perceived value significantly influences continuance intention. In addition, trust in broadcasters moderates the relationship between perceived value and continuance intention.Originality/valueThe current study adds significantly to the body of knowledge about livestreaming by examining the direct determinants of perceived value and thus delineating how perceived value influences continuance intention. The findings yielded also illustrate the role of trust in broadcaster as the moderator of the link between perceived value and continuance intention.
Enhanced DWA algorithm for local path planning of mobile robot
Authors: Lai Xin , Wu Dan , Wu Di , Li Jia He , Yu Hang 
Published: August 2022

Purpose
The purpose of this study is to solve the problems of poor stability and high energy consumption of the dynamic window algorithm (DWA) for the mobile robots, a novel enhanced dynamic window algorithm is proposed in this paper.

Design/methodology/approach
The novel algorithm takes the distance function as the weight of the target-oriented coefficient, and a new evaluation function is presented to optimize the azimuth angle.

Findings
The jitter of the mobile robot caused by the drastic change of angular velocity is reduced when the robot is closer to the target point. The simulation results show that the proposed algorithm effectively optimizes the stability of the mobile robot during operation with lower angular velocity dispersion and less energy consumption, but with a slightly higher running time than DWA.

Originality/value
A novel enhanced dynamic window algorithm is proposed and verified. According to the experimental result, the proposed algorithm can reduce the energy consumption of the robot and improves the efficiency of the robot.
Are we talking about merger or acquisition? Defining the integration process
Authors: Thelisson Anne-Sophie 
Published: August 2022

Purpose
When talking about mergers and acquisitions (M&As), few announcements clearly define if the operation will deal with a merger (where firms have an equal-to-equal relation) or acquisition (when one firm is in control of the operation and decides the integration process). Operations are commonly labeled M&A. Nevertheless, mergers remain rare, and the authors see that most of the time, operations designed and integrated with firms as equals end in the control of one of the entities over the other.

Design/methodology/approach
The authors investigate how two CEOs and their managers communicate during the due diligence period of a merger. The author describes the project merger of two French companies using longitudinal data.

Findings
This in-depth case study provides new insights into the due diligence period and the differences between M&As. The findings highlight how the decision to add an associate from a rival firm to the board ended the merger project as the situation evolved toward an acquisition in CEOs’ minds.

Research limitations/implications
The limitations are those concerning a single case study.

Practical implications
The paper highlights the complexity of merger negotiations and the unexpected events faced by stakeholders. The analysis, thus, contributes to an inclusive and integrative view of the challenges in the due diligence process, whereas first defining the operation as a merger or an acquisition is a first step in identifying the degree to which autonomy and interdependence will be given across firms, and how some strategic decisions will be implemented. This case study highlights two specific items that can be understood by managers as key elements in deal success: defining operations as a merger or an acquisition help internal and external stakeholders in planning the operation; leaving space for adjustment among partners engaged in negotiations during the due diligence period is also useful.

Social implications
Despite their frequency, merger and acquisition failures remain surprisingly high. This paper explores how stakeholders deal with merger negotiations.

Originality/value
The case provides insights into the due diligence period and the way minor events can impact the planned integration. Theoretical concepts and empirical findings from the literature are combined to present a single consistent picture. To the best of the authors’ knowledge, few studies address insights on strategic decisions made as the negotiation period remains a secret and sensitive stage, especially for a failed deal, but we were able to delve beneath the surface.
Exploring the spatial structure of Toon historical town courtyard houses: topological characteristics of the courtyard based on a configuration approach
Authors: Kamelnia Hamed , Hanachi Pirouz , Moayedi Mina 
Published: August 2022

PurposeIn response, this study developed a mathematical and computational method, through spatial configurations with justified plan graph (JPG), drawn from Space Syntax to extract essential information of the spatial topology of 13 valuable traditional courtyard houses located in Toon historical city of Iran.Design/methodology/approachHistorical vernacular housing has always been designed to incorporate and reflect the local lifestyle and cultural conditions. “Courtyard” is a fundamental part of traditional Iranian houses. This traditional building type includes a walled boundary and a complex of open, semi-enclosed and enclosed spaces. This study investigates the traditional houses in Toon historical town. Toon is one of the ancient towns in southeast Iran, including old courtyard houses in its heritage context. The spatial influence of the courtyard contributes to the formation of this famous architectural type.FindingsThe results show the remarkable impact of this space on dominating the plan of traditional Toon houses configuration compared to other spaces in all cases. Furthermore, spatial accessibility has changed over time, and the Safavid period had a higher level of integration and lower level of accessibility (mean i = 7.03) rather than the Qajar period (mean i = 6.34); also, privacy has decreased progressively.Originality/valueThe knowledge of characteristics of this historical architecture needs to be gathered for the preservation and conservation of the built heritage. Hence, the principle behind traditional Iranian courtyards was investigated to recognize the difference between the spatial influence of the courtyard and other spaces and the changes in the courtyard over time.
Following the data: an analysis of two schools' use of social emotional data
Authors: Roegman Rachel , Tan Kevin , Tanner Nathan , Yore Caitlin 
Published: August 2022

PurposeDrawing on Coburn and Turner's framework for research on data use, this study looks at how contextual factors support interactions around data. In so doing, the authors contribute to the emerging body of literature on administrators supporting high school students' social-emotional learning (SEL).Design/methodology/approachThis two-site case study “follows the data” that were shared with administrators at two high schools based on a longitudinal study of students' SEL. One author of this study has been leading a research project of high school students' SEL in two high schools from two different districts in a Midwest university town since 2017. This study follows what happened in both high schools after the author shared students' SEL data with district personnel.FindingsFindings showed that participants were invested in increasing SEL programming. However, SEL data moved in different ways through the two schools, and all individuals had different ideas about which data were important. Each district dealt with a specific set of organizational norms, existing inequities, and beliefs systems that influenced which SEL data were noticed and how, if at all, data spurred action.Originality/valueSpecific aspects of organizational contexts support and constrain SEL data use. Both cases suggest researchers can guide data use practices that can advance students' SEL. However, each district dealt with a specific set of educational inequities, which influenced which data were noticed and how, if at all, data spurred action. Importantly, data-driven decision-making must be conducted from an equity lens, lest the process replicate existing inequities.
The dynamic relationship between firms’ cash reserves and financial leverage: evidence from MENA emerging markets
Authors: Almustafa Hamza , Kalash Ismail 
Published: August 2022

PurposeThis paper investigates the impact of financial leverage on corporate cash holdings in the Middle East and North African (MENA) emerging markets.Design/methodology/approachThe author applies the dynamic modeling approach to data from nonfinancial firms listed in 10 MENA countries between 2010 and 2019. The empirical model avoids the shortcomings of the prior literature by including indicators of the dynamics of the financial leverage to account for its persistence in the corporate cash holdings reserves.FindingsThis research reports a significant negative relationship between corporate cash holdings and financial leverage. The results support the pecking order model, suggesting that leverage can be regarded as a substitute for holding a larger amount of cash and marketable securities. The author argues that the negative relationship between financial leverage and corporate cash holdings reinforces the precautionary motive to have internal cash reserves rather than external debt to support capital and investment activities by firms in the MENA emerging markets.Practical implicationsThe results of this research provide important insights into cash and capital structure management for nonfinancial listed firms in the MENA emerging markets. Specifically, the paper will help managers to understand the dynamic financial leverage determinants of holding cash in corporations in the MENA emerging markets and encourage policymakers to financially determine the corporate capital structure and cash holdings based on cost and benefits. Managing the firm's capital structure and cash holdings based on trade-offs between costs and benefits would enhance operating cash flow which may play an important role in creating value for shareholders.Originality/valuePrior studies have commonly been concerned with the determinants of corporate cash holdings, but few have investigated the dynamic financial leverage determinants of corporate cash holdings. This paper draws attention to this issue within the context of MENA emerging markets. To the authors' best knowledge, this is the first study that explores the relationship between cash holdings and financial leverage in MENA emerging markets.