bluuebunny/crossref_metadata_2025 huggingface dataset:
In silicobacteria evolve robust cooperation via complex quorum-sensing strategies
Authors: Wang Yifei , Rattray Jennifer B. , Thomas Stephen A. , Gurney James , Brown Sam P.
Published: April 2019

Many species of bacteria collectively sense and respond to their social and physical environment via ‘quorum sensing’ (QS), a communication system controlling extracellular cooperative traits. Despite detailed understanding of the mechanisms of signal production and response, there remains considerable debate over the functional role(s) of QS: in short, what is it for? Experimental studies have found support for diverse functional roles: density sensing, mass-transfer sensing, genotype sensing, etc. While consistent with theory, these results cannot separate whether these functions were drivers of QS adaption, or simply artifacts or ‘spandrels’ of systems shaped by distinct ecological pressures. The challenge of separating spandrels from drivers of adaptation is particularly hard to address using extant bacterial species with poorly understood current ecologies (let alone their ecological histories). To understand the relationship between environmental challenges and trajectories of QS evolution, we used an agent-based simulation modeling approach. Given genetic mixing, our simulations produce behaviors that recapitulate features of diverse microbial QS systems, including coercive (high signal / low response) and generalized reciprocity (signal auto-regulation) strategists — that separately and in combination contribute to QS-dependent resilience of QS-controlled cooperation in the face of diverse cheats. We contrast ourin silicoresults with bacterial QS architectures that have evolved under largely unknown ecological contexts, highlighting the critical role of genetic constraints in shaping the shorter term (experimental evolution) dynamics of QS. More broadly, we see experimental evolution of digital organisms as a complementary tool in the search to understand the emergence of complex QS architectures and functions.

Author summary

Bacteria communicate and cooperate using complex cell-cell signaling systems known as quorum-sensing (QS). While the molecular mechanisms are often well understood, the reasons why bacteria use QS are less clear — how has QS aided survival and growth? The answer to this question is dependent on the environment of adaptation, and unfortunately our current understanding of QS bacterial ecology is broadly lacking. To address this gap, we studied the evolution of ‘digital organisms’, individual-based computer simulations of bacterial populations evolving under defined environmental contexts. Our results pinpoint how simple environmental challenges (variable density and genetic mixing) can lead to the emergence of complex strategies that recapitulate features of bacterial QS, and open a path towards reverse-engineering the environmental drivers of QS.
Motion prediction enables simulated MR-imaging of freely moving model organisms
Authors: Reischl Markus , Jouda Mazin , MacKinnon Neil , Fuhrer Erwin , Bakhtina Natalia , Bartschat Andreas , Mikut Ralf , Korvink Jan G.
Published: April 2019

Abstract

Magnetic resonance tomography typically applies the Fourier transform tok-space signals repeatedly acquired from a frequency encoded spatial region of interest, therefore requiring a stationary object during scanning. Any movement of the object results in phase errors in the recorded signal, leading to deformed images, phantoms, and artifacts, since the encoded information does not originate from the intended region of the object. However, if the type and magnitude of movement is known instantaneously, the scanner or the reconstruction algorithm could be adjusted to compensate for the movement, directly allowing high quality imaging with non-stationary objects. This would be an enormous boon to studies that tie cell metabolomics to spontaneous organism behaviour, eliminating the stress otherwise necessitated by restraining measures such as anesthesia or clamping.

In the present theoretical study, we use a phantom of the animal modelC. elegansto examine the feasibility to automatically predict its movement and position, and to evaluate the impact of movement prediction, within a sufficiently long time horizon, on image reconstruction. For this purpose, we use automated image processing to annotate body parts in freely movingC. elegans, and predict their path of movement. We further introduce an MRI simulation platform based on brightfield-videos of the moving worm, combined with a stack of high resolution transmission electron microscope (TEM) slice images as virtual high resolution phantoms. A phantom provides an indication of the spatial distribution of signal-generating nuclei on a particular imaging slice. We show that adjustment of the scanning to the predicted movements strongly reduces distortions in the resulting image, opening the door for implementation in a high-resolution NMR scanner.
Cryo-EM reveals the asymmetric assembly of squid hemocyanin
Authors: Tanaka Yoshikazu , Kato Sanae , Stabrin Markus , Raunser Stefan , Matsui Takashi , Gatsogiannis Christos
Published: April 2019

The oxygen transporter of molluscs, hemocyanin, consists of long pearl-necklace-like subunits of several globular domains. The subunits assemble in a complex manner to form cylindrical decamers. Typically, the first six domains of each subunit assemble together to form the cylinder wall, while the C-terminal domains form a collar that fills or caps the cylinder. During evolution, various molluscs have been able to fine-tune their oxygen binding by deleting or adding C-terminal domains and adjusting their inner-collar architecture. However, squids have duplicated one of the wall domains of their subunits instead. Here, using cryo-EM and an optimized refinement protocol implemented inSPHIRE, this work tackled the symmetry-mismatched structure of squid hemocyanin, revealing the precise effect of this duplication on its quaternary structure and providing a potential model for its structural evolution.
Competitive advantage and industrial district
Authors: Claver-Cortés Enrique , Marco-Lajara Bartolomé , Seva-Larrosa Pedro , Ruiz-Fernández Lorena
Published: April 2019

Purpose

This paper aims to know the dimension and scope that research on the district effect has had in the literature about industrial districts, as well as to shed some light on the connection between industrial districts and business results; or expressed differently, on how being located in an industrial district or not affects or might influence the performance of the firms located therein.

Design/methodology/approach

The purpose of this paper has been achieved through an exhaustive review of the empirical literature dedicated to the so-called district effect. The papers selected in the analysis were selected on the basis of the following criteria: (1) publications in scientific journals; (2) studies carried out in Spain and Italy; and (3) works published between 1994 and 2017.

Findings

The outcome of the literature review suggests, on the one hand, that the debate on the extent to which the territory influences the competitiveness of firms located in industrial districts still remains a topic of great interest. It can additionally be observed that most of the works dedicated to measuring the district effect have done so using three dimensions: (1) productivity/efficiency; (2) international competitiveness; and (3) innovation.

Practical implications

From a theoretical perspective, the findings of this paper make it possible to carry out an integrating proposal for the measurement of the district effect which revolves around three dimensions (productivity/efficiency; international competitiveness; and innovation).

Originality/value

This paper makes a twofold contribution to the literature: (i) it brings together the most important empirical contributions that measure the competitive advantages obtained by firms located in industrial districts through the district effect; and (ii) it theoretically and empirically establishes the essential dimensions of that effect.
The impact of actors, networks and institutions in the cluster’s evolution
Authors: Scur Gabriela , Garcia Renato
Published: April 2019

Purpose

This paper aims to analyze the impact of the capabilities and strategies of the actors (micro-dynamics), learning process and networks (meso-dynamics) and institutions (macro-dynamics) in the evolution of the Brazilian ceramic clusters. Based on these experiences, managerial and policy implications are suggested.

Design/methodology/approach

Main data were gathered through 22 in-depth face-to-face interviews with managers and industry experts. The data were complemented by documentary analysis, including brand documents, descriptions of internal processes and Brazilian and international ceramics magazines and journals. In addition, the authors also use information from the previous experience of the authors who have been studying the sector for more than 15 years.

Findings

The paper provides empirical insights about the main characteristics of the evolution of two main Brazilian ceramic tiles clusters, as well as how there are different patterns of evolution among them. The results of this paper show that Brazilian ceramic tile clusters do not necessarily follow the life cycle model of their dominant industry, by proving evidence that different clusters in the same industry can follow different evolutionary paths.

Research limitations/implications

This paper shed light on a multi-level approach (micro, meso and macro) of dynamics of the clusters and how it impacts the cluster’s life cycle. The micro-dynamics dimension was analyzed by the capabilities and strategies of local ceramic tile manufacturers. The meso-dynamics are being considered the localized learning processes, especially from those that arise from interactions, collaboration and networks carried by local and foreign suppliers. The macro-dynamics were considered by the role of local demand, factors conditions, institutions, historical legacy in the clusters’ emergence along with path dependence mechanisms.

Practical implications

The paper includes implications for both clusters to promote innovation, particularly to keep and create market and technological leadership through the establishment of partnership between firms and clients, regulators and research centers and universities are crucial for innovation.

Originality/value

This paper fulfils an identified lack of attention regarding the under-appreciation of the context-specific issues such as the capabilities of the actors, networks and institutions that may influence the long-term development of clusters.
Not one segment: using global and local BoP characteristics to model country-specific consumer profiles
Authors: Lappeman James , Ransome Kristin , Louw Zach
Published: April 2019

Purpose

This paper aims to show that a generic bottom-of-the-pyramid (BoP) segmentation strategy does not represent a multi-country BoP consumer profile. A series of multinational entry failures has clearly shown that a one-size-fits-all strategy is inappropriate for emerging markets, especially in Africa.

Design/methodology/approach

The study analysed literature defining and profiling BoP consumers at both a global and local level using South Africa as a case study. Being Africa’s largest economy, South Africa was an ideal subject. The findings were then independently triangulated with seven experts for validation.

Findings

The results show that the South African BoP has eight characteristics that align with definitions in global BoP consumer literature. An additional five characteristics were identified that were not general BoP characteristics, and that applied specifically to South Africa.

Practical implications

The findings add to the growing evidence that BoP markets are complex and heterogeneous, and they make a case to consider each BoP market individually. As there is yet to be a model to define BoP market differences systematically, this study provides a foundation for new developments in BoP segmentation in Africa and in other emerging markets.

Originality/value

While there is evidence that BoP markets are complex and heterogeneous, there is yet to be a model to begin the process of defining these differences systematically to improve strategic direction for multinational companies and regional decision makers. This study, therefore, provides a foundation for new developments in this field of segmentation in Africa and in other emerging markets globally.
The influence of place on health-care customer creativity
Authors: Snyder Hannah , Witell Lars , Elg Mattias , McColl-Kennedy Janet R.
Published: April 2019

Purpose

When using a service, customers often develop their own solutions by integrating resources to solve problems and co-create value. Drawing on innovation and creativity literature, this paper aims to investigate the influence of place (the service setting and the customer setting) on customer creativity in a health-care context.

Design/methodology/approach

In a field study using customer diaries, 200 ideas from orthopedic surgery patients were collected and evaluated by an expert panel using the consensual assessment technique (CAT).

Findings

Results suggest that place influences customer creativity. In the customer setting, customers generate novel ideas that may improve their clinical health. In the service setting, customers generate ideas that may improve the user value of the service and enhance the customer experience. Customer creativity is influenced by the role the customer adopts in a specific place. In the customer setting customers were more likely to develop ideas involving active customer roles. Interestingly, while health-care customers provided ideas in both settings, contrary to expectation, ideas scored higher on user value in the service setting than in the customer setting.

Research limitations/implications

This study shows that customer creativity differs in terms of originality, user value and clinical value depending on the place (service setting or customer setting), albeit in one country in a standardized care process.

Practical implications

The present research puts customer creativity in relation to health-care practices building on an active patient role, suggesting that patients can contribute to the further development of health-care services.

Originality/value

As the first field study to test the influence of place on customer creativity, this research makes a novel contribution to the growing body of work in customer creativity, showing that different places are more/less favorable for different dimensions of creativity. It also relates customer creativity to health-care practices and highlights that patients are an untapped source of creativity with first-hand knowledge and insights, importantly demonstrating how customers can contribute to the further development of health-care services.
Value-in-acquisition: an institutional view
Authors: Chipp Kerry , Williams E. Patricia , Lindgreen Adam
Published: April 2019

Purpose

By combining consumer culture theory and service dominant logic, this study proposes that value might be understood as value-in-acquisition, such that value outcomes result from the acquisition process in which broader social forces shape the exchange process.

Design/methodology/approach

This study addresses low-income consumers, for whom societal arrangements strongly determine service interactions. Qualitative interviews reveal service value processes and outcomes for low-income consumers during acquisition processes.

Findings

For low-income consumers, inclusion, status, resource access and emotional relief represent key value outcomes. Important value processes shape those value outcomes, reflecting broader societal arrangements at macro, meso and micro levels. Marketing constitutes an institutional arrangement that establishes an empowered “consumer” role. Value processes are hindered if consumers sense that their agency in this role is diminished, because marketing interactions give precedence to other social roles.

Research limitations/implications

Marketing should be studied as an institutional arrangement that shapes value creation processes during acquisition. Micro-level value processes have important implications for service quality and service value. Value outcomes thus might be designed in the acquisition process, not just for the offering.

Practical implications

The acquisition process for any good or service should be designed with its own value proposition, separate to the core product or service. Careful design of value processes during acquisition could mitigate conflict between social roles and those of consumption.

Originality/value

There is value in the acquisition process, independent of the value embedded in the goods and services.
Entrepreneurial attitudes in the structure of students’ economic minds
Authors: Zabelina Ekaterina , Deyneka Olga , Tsiring Diana
Published: April 2019

Purpose

The purpose of this paper is to explore how students’ entrepreneurial attitudes are related to their economic attitudes regarding business, investments, savings and consumption. The study presents a new research tool to analyze the characteristics of the economic mind – the economic attitudes questionnaire.

Design/methodology/approach

The method consists of a multiple-factorial questionnaire, a verification of reliability and internal validity (exploratory and confirmation factor analyses), a quantitative survey and a correlation analysis.

Findings

Two main ways of preparing students for a market economy are identified: one is connected to entrepreneurship, and the other to rational investment and financial planning. The complex nature of economic attitudes’ interaction is confirmed: by the direct relationships between entrepreneurial attitudes of students and investment activity, and between risk and satisfaction and consumer opportunities, as well as by the negative relationships between entrepreneurial attitudes and the level of mistrust to banking structures, unwillingness to make savings, unwillingness to share and financial pessimism. The economic attitudes questionnaire was developed and it showed sufficient validity and reliability on samples of student youth.

Research limitations/implications

The study was limited to Russian students.

Originality/value

Adapting the questionnaire to other cultures will allow conducting cross-cultural research of entrepreneurial attitudes, which may be relevant in the global economy.
An evaluation of middle-income group housing in Kolkata, India
Authors: Kaur Amit , Gupta Sumana
Published: April 2019

Purpose

This study aims to assess the satisfaction level of middle-income group (MIG) residents of government group housings of Kolkata, India. Further, a Composite Satisfaction Index (CSI) was also devised for assessing the satisfaction level.

Design/methodology/approach

The satisfaction level was assessed in three domains – “within premises”, “at neighbourhood” and “with cost” – incurred and questionnaires were designed to conduct primary survey. Question on overall level of satisfaction “with location” was also included. All satisfaction responses were recorded on a five-point Likert scale. Subsequently, a CSI – a weighted average of satisfaction for attribute “with location” and “with cost” – was devised. The weights were assigned through expert opinion survey using Delphi technique. Data being ordinal in nature, a two-step approach was adopted – initially through exploratory factor analysis, contributing attributes were identified and later a Generalised Ordered Logit Model was fitted in STATA. “Monetary benefits” were calculated as a difference of actual expenditure incurred from recommended expenditure towards regular transportation and housing. Mean satisfaction scores for attributes “with cost” were validated with “monetary benefits”.

Findings

Attribute “with cost” contributed significantly towards the overall level of satisfaction “with location”. The computed CSI values also comply with the findings, indicating the reliability of the index in similar contexts. The government group housing model was successful in its outreach towards the intended beneficiaries.

Practical implications

The CSI devised will help the MIG in identifying appropriate residential housing locations and enable policymakers in reviewing group housings.

Originality/value

Residential satisfaction studies were not specific to MIG residents considering attribute “with cost”. Hence, this study contributed to the existing knowledge in this specific context.
Real estate prices and stock market in Germany: analysis based on hedonic price index
Authors: Gokmenoglu Korhan , Hesami Siamand
Published: April 2019

Purpose

Real estate and stocks are two major asset types in an investor’s portfolio. Therefore, this paper aims to investigate the relationship between these two markets to provide a valuable insight into the process of portfolio optimization and security selection.

Design/methodology/approach

This study examines the long-run relationship between residential real estate prices and stock market index in the case of Germany for the period of 2005-2017 by applying time series econometrics techniques. To this aim, this study uses Hedonic House Price Index as a proxy for real estate prices and DAX30 as a proxy for stock prices. Moreover, three additional variables, namely, consumer confidence, credit availability and supply of mortgage loans, are incorporated as control variables to assess the robustness of the results.

Findings

Obtained empirical results indicate a long-run relationship between stock prices and real estate prices which suggests that in long-run, there is no diversification benefit from allocating stock and real estate assets in a portfolio. This finding is especially important for long-term investors such as pension funds.

Originality/value

To the authors’ best knowledge, this is the first study that empirically investigates the relationship between the real estate market and stock prices using the Hedonic Price Index for the case of Germany.
How can the ISO 9000 QMS improve the organizational innovation of supply chains?
Authors: Shi Yuwen , Lin Wei , Chen Ping-Kuo , Su Chun-Hsien
Published: April 2019

Purpose

Studies have not investigated how the International Standards Organization (ISO) 9000 quality management system (QMS) guides manufacturers’ and their partners’ creative processes in devising an innovative supply chain structure. Accordingly, this study aims to explore this subject.

Design/methodology/approach

A systematic literature analysis was conducted to explore how the ISO 9000 QMS might guide manufacturers’ and supply chain partners’ creative processes and the further development of an innovative supply chain organizational structure. The systematic literature analysis is divided into the following two parts: the first part collects related literature to analyze and explore based on the research questions and purpose. The second part is an association analysis. The results of the association analysis show that these related literatures are suitable for the analysis and exploration of the research questions and purpose.

Findings

This study developed an analytic framework to compare the elements of four components of the ISO 9000 QMS and the ingredients that drive creativity and innovation; the study also reviewed related publications to deeply analyze the relationship between the elements of the four components and the ingredients of creativity and innovation. The authors observed that when manufacturers and partners implement the ISO 9000 QMS, their use of the elements of the four components engages all ingredients and thereby facilitates the manufacturers’ and partners’ creative process in the development of an innovative organizational structure.

Research implications

According to the results of the analysis, practitioners can understand how to improve the innovation of an organization’s supply chain from ISO 9000 QMS components. In addition, the research has resulted in developing additional research propositions concerning the relationship between the four components of the ISO 9000 QMS and ingredients that drive creativity and innovation. Based on these propositions, more research hypotheses can be further developed.

Originality/value

The research results prove that the ISO 9000 QMS has a positive effect on facilitating the creative process and innovation, with regard to the organizational structure, and it also provides the underlying reasons for this effect.
A review of the use of portable technologies as observational aids in the classroom
Authors: Goh Felicia , Carroll Annemaree , Gillies Robyn M.
Published: April 2019

Purpose

Current classroom observation strategies include questionnaires, interviews, tests, self-report metrics and live or video review observation. However, these traditional methods are subject to biases from observers in determining behavior nuances, as well as being difficult to analyze for rapid and practical feedback. In addition, the invasiveness of extra body equipment in the classroom may alter the dynamic between students and teachers. The emergence of portable devices into mainstream usage has opened a pathway for a relatively novel source of quantitative data, free from observer bias and often with accompanying analytical tools for convenience. The purpose of this study is to summarize current uses of portable technology and explore how such devices could be used as monitoring tools by both schools and education researchers.

Design/methodology/approach

Functions based on utility outside the education field are proposed for monitoring student activity, posture and movement, as well as proximity and relationships to others and their environment. Deterrents to device implementation in regular classroom use, such as the importance of considering ethical issues and hardware limitations, are also covered.

Findings

While current portable technology is unlikely to replace more commonly used techniques of observing classes, they have the capacity to augment qualitative strategies, particularly in the area of real-time data output.

Research limitations/implications

Ideally, the lack of unbiased observational tools available and increased adoption of portable devices in classrooms could prompt future advances in technology for teaching and learning environments.

Originality/value

This review summarizes potential uses for portable technology in classroom observation strategies undertaken by researchers and teachers to improve learning and teaching practices.
Tribocorrosion behavior of electroless Ni-P/Ni-B duplex coating on AA7075 aluminum alloy
Authors: Mindivan Harun
Published: April 2019

Purpose

This paper aims to investigate the structural, corrosion and the study of tribocorrosion features of the AA7075 aluminum alloy with and without the application of electroless Ni-P/Ni-B duplex coating with a thickness of approximately 40 microns.

Design/methodology/approach

Surface characterization of the samples was made by structural surveys (light optic microscope, scanning electron microscopic examinations and X-ray diffraction analyses), hardness measurements, corrosion and tribocorrosion tests.

Findings

Results of the experiments showed that upper Ni-B coating deposited on the surface of first Ni-P layer by duplex treatment caused remarkable increment in the hardness, corrosion resistance and tribocorrosion performance as compared to the AA7075 aluminum alloy.

Originality/value

This study can be a practical reference and offers insight into the effects of duplex treating on the increase of hardness, corrosion and tribocorrosion performance.
Enhancement of roller bearing fatigue life by innovative production processes
Authors: Pape Florian , Maiss Oliver , Denkena Berend , Poll Gerhard
Published: April 2019

Purpose

The efficient and economical use of natural resources is a big issue. Machine elements with a rolling contact are highly relevant because of their wide application in technical systems and a large production quantity. Innovative hard machining can reduce the friction and increase the fatigue strength of rolling element bearings. The purpose of this study is to focus on the surface properties of such parts.

Design/methodology/approach

A new model to predict bearing fatigue life is presented which takes compressive residual stresses in the bearing subsurface area into consideration. The investigated bearings were machined by the processes of hard turning, hard turning with subsequent deep rolling and a combination of hard turning and deep rolling (turn-rolling) in one process step. Changes in the residual stress state during bearing fatigue tests were investigated and the influence of residual stresses on the bearings fatigue life was researched.

Findings

Both combinations including the deep rolling process decrease the surface roughness and induce compressive residual stresses. As a result, the L10 fatigue life of roller bearings was increased by the factor of 2.5. Owing to the developed models, this effect can be considered within the design process.

Originality/value

In the context of the research program “Resource efficient Machine Elements (SPP1551),” machining processes of bearings were investigated regarding the bearing fatigue life. By inducing beneficial residual stresses on the bearings’ subsurface area, the fatigue life could be increased. Thus higher resource efficiency was achieved. To increase the productivity, a combination of hard turning and deep rolling was evaluated.
Study on rheological properties of aviation lubricating oil under conditions of heavy load, high speed, and high temperature
Authors: Li Zhen , Zhao Xiaoli , Zheng Dezhi , Wang Tingjian , Gu Le , Wang Liqin
Published: April 2019

Purpose

This study aims to evaluate the rheological properties of aviation lubricating oil under conditions of heavy load, high speed and high temperature and the applicability of the classical rheological model under severe conditions.

Design/methodology/approach

A Chinese aviation lubricating oil was used and its traction curves were obtained using a new two-disk tribotester. Its rheological parameters were calculated based on empirical formulae. Moreover, the traction force was calculated based on the classical Eyring rheological model.

Findings

The traction curves are obtained with respect to contact pressure, temperature and rolling speed. The rheological parameters are significantly influenced by environmental factors, especially viscosity. The traction force calculated using the Eyring model is consistent with the experimental results.

Originality/value

A novel two-disk tribotester was designed using a gas bearing and speed–force closed-loop control to ensure measurement accuracy. The mechanism of rheological properties was analyzed and the applicability of the classical rheological model under severe conditions was verified. It provided an experimental and theoretical basis for expanding the application of classical rheological models under extreme conditions.
Lose your weight with online buddies: behavioral contagion in an online weight-loss community
Authors: Song Xiaolong , Jin Jiahua , Liu Yi-Hung , Yan Xiangbin
Published: April 2019

Purpose

A question of interest is whether online social networks are effective in promoting behavioral changes and weight loss. The purpose of this paper is to examine the contagion effect of an online buddy network on individuals’ self-monitoring behavior.

Design/methodology/approach

This study collects data from an online weight-loss community and constructs an online buddy network. This study compares the effects of the network structure of the buddy network and the actor attributes when predicting self-monitoring performance by employing the auto-logistic actor attribute models.

Findings

This study confirms the contagion effect on weigh-in behavior in the online buddy network. The contagion effect is significantly predictive when controlling for actor attribute and other network structure effects.

Originality/value

There is limited evidence that one’s weight-related behavior can be affected by online social contacts. This study contributes to the literature on peer influence on health by examining the contagion effect on weight-related behavior between online buddies. The findings can assist in designing peer-based interventions to harness influence from online social contacts for weight loss.
A spatiotemporal exploratory analysis of real estate sales in Turkey using GIS
Authors: Erdoğan Saffet , Memduhoğlu Abdulkadir
Published: April 2019

Purpose

The purpose of this paper is to examine the real estate sales in Turkey on a district basis to reveal the current state of real estate sales and any meaningful changes in the last period. The real estate market is important and is an indicator of the country’s general economic health, as real estate is seen as an investment.

Design/methodology/approach

As a powerful method of spatial analysis and evaluation, geographic information systems have been used to examine real estate data in both spatial and temporal ways. In this study, 14 years of sales data covering the years 2004 to 2017 obtained from government agencies on a district basis were evaluated using spatiotemporal methods. Several maps were produced using Getis-Ord Gi* and local Moran’s I indices, which showed the spatiotemporal change of sales and sales rates.

Findings

When looking at the maps, provinces such as Istanbul, Ankara, Izmir, Antalya and their surrounding districts have buoyant real estate markets compared to the other side of the country. Real estate sales are more stagnant in the eastern and northern parts of the country. In addition, the authors found that the growth rate of annual average real estate sales was approximately seven times higher than the annual average population growth.

Originality/value

This spatiotemporal study, which presents 14 years of performance data of the real estate market and, by extension, the economic situation, also highlights the regions that stand out for investment planning throughout the country. The results of spatiotemporal analysis also present a new way of real estate market visualization using maps with well-designed categorizations.
A disaster typology towards informing humanitarian relief supply chain design
Authors: Mackay Jonathon , Munoz Albert , Pepper Matthew
Published: April 2019

Purpose

The purpose of this paper is to construct a typology of a disaster that informs humanitarian-relief supply chain (HRSC) design across the stages of disaster relief.

Design/methodology/approach

In addition to an interdisciplinary review of pertinent literature, this paper utilises a typology construction method to propose theoretically and methodologically sound dimensions of disasters.

Findings

Whilst semantic arguments surrounding the concept of a “disaster” are ongoing, the authors propose three typologies based upon six dimensions that serve as interdependent variables informing resultant HRSC design considerations. These are speed of onset, time horizon, spatial considerations, affected population needs, perceived probability of occurrence and perceived magnitude of consequence. These combinational and independent relationships of the variables offer insight into key HRSC design-making considerations.

Research limitations/implications

The study improves conceptual knowledge of disasters, distilling the concept to only the dimensions applicable to HRSC design, omitting other applications. The typologies provide empirical cell types based on extant literature, but do not apply the models towards new or future phenomena.

Practical implications

This paper provides HRSC practitioners with normative guidance through a more targeted approach to disaster relief, with a focus on the impacted system and resulting interactions’ correspondence to HRSC design.

Originality/value

This paper provides three typological models of disasters uniquely constructed for HRSC design across the various stages of disaster relief.
A study of the self-perceived competencies regarding the knowledge and skills of healthcare providers in the Expanded Program on Immunization in Thailand
Authors: Rutchanagul Pregamol , Sangnimitchaikul Wipada
Published: April 2019

Purpose

The Expanded Program on Immunization (EPI) has still been found to offer services that do not comply with standards. The purpose of this paper is to ascertain competency in terms of the knowledge and skills of the EPI staff.

Design/methodology/approach

The research design was a mixed-methods approach. The quantitative method employed a questionnaire survey on the perceived competency of 382 EPI staffs from six regions in Thailand. This was paired alongside of the qualitative method, where four staffs were in-depth interviewed, and the performance of the EPI staffs was observed.

Findings

The overall perceived competency in the work of immunization was at a high level. A comparative analysis between the quantitative and qualitative data showed findings in three categories. First, the perception of competency was high, and performance conformed to standards in the preparation of the setting and equipment for providing the service; second, the perception of competency was high, but in the performance of their work the participants did not comply completely with standards for scheduling the immunization appointments or for vaccine storage; and third, the perception of competency was either moderate or low, and the performance of work was inadequate for vaccine estimations, registering reports, and dealing with adverse events following immunization.

Originality/value

The findings showed a gap between perception of knowledge-and-skill competency and actual practice in EPI service. Effective cooperation among involved organizations in order to improve the standard of performance in expanding the quality of EPI service provision in Thailand is suggested.
Managing informal service organizations at the base of the pyramid (BoP)
Authors: Reynoso Javier , Cabrera Karla
Published: April 2019

Purpose

This paper aims to explore and learn about managerial practices of informal services at the base of the pyramid (BoP).

Design/methodology/approach

The study reports findings of an empirical research conducted in 16 cities in Mexico during a two-year period. Managerial practices in 327 micro-businesses were identified and analyzed after conducting direct observation and personal interviews with owners, employees and customers of these BoP informal service businesses.

Findings

The paper shows that managerial practices of BoP informal service micro-businesses are developed through a dynamic, integrated network of owner, employees and customers who integrate scarce resources building win-win-win relationships to satisfy their basic daily needs.

Practical implications

The creation and management of a BoP informal service business is mainly a matter of satisfying basic needs, aiming to positively transform a community by improving well-being. This paper provides insights to understand those relationships and interactions among the main actors involved, highlighting the need to identify and integrate the BoP service management cycle to better address their needs.

Originality/value

This paper proposes a conceptual service management framework for informal micro-businesses at the BoP integrating the owners, employees and customers’ perspectives. Three corresponding cycles are identified and discussed, which are useful to elicit relevant characteristics of key roles, activities, interactions and relationships taking place in informal services.
Beyond green façades: active air-cooling vertical gardens
Authors: Davis Michael Maks , Vallejo Espinosa Andrea Lorena , Ramirez Francisco Rene
Published: April 2019

Purpose

Vertical gardens offer multiple benefits in urban environments, including passive cooling services. Previous research explored the use of “active vertical gardens” as potential evaporative air-cooling units by developing a mathematical model based on the FAO-56 Penman Monteith equation. Further research showed that active vertical gardens function best by creating an airflow in the cavity behind the garden such that air is cooled by flowing over the water-saturated garden substrate. The purpose of this paper is to improve the quantification of active vertical garden performance.

Design/methodology/approach

A building-incorporated vertical garden was built in Quito, Ecuador, with an air inlet at the top of the garden, an air cavity behind the garden and where air was expelled from the base. Measurements were made of air temperature, humidity and velocity at the air inlet and outlet.

Findings

The active vertical garden cooled the air by an average of 8.1 °C with an average cooling capacity of 682.8 W. Including the effects of pre-cooling at the garden inlet, the garden cooled the air by an average of 14.3 °C with an average cooling capacity of 1,203.2 W.

Originality/value

The results are promising and support the potential for active vertical gardens to be incorporated into building services and climate control.
A novel non-isolated positive output voltage buck-boost converter
Authors: Mohapatra Tapas Kumar , Dey Asim Kumar , Mohapatra Krushna Keshab , Sahu Binod
Published: April 2019

Purpose

A two switches non-isolated DC-DC novel buck-boost converter for charging the battery of electric vehicle is projected in this paper. The performance of the converter is compared with conventional buck-boost and transformer-less P/O buck-boost converter by Shan and Faqiang. The detail operation and performance analysis of the proposed converter is described both in continuous conduction mode and discontinuous conduction mode. A state space model and simulation model is designed in MATLAB. The PID controller parameters are tuned using Single-objective Salp swarm optimization algorithm using MATLAB. The controller is implemented using DSP board. The hardware and simulation results are projected in the paper to validate the effectiveness of the proposed buck-boost converter. A comparison analysis is projected among conventional converter and Shan & Faqiang converter.

Design/methodology/approach

The converter state space model is designed and simulation model is also developed in MATALAB. The controller is implemented using DSP board. The parameters are obtained using optimization technique using SSA algorithm. The hardware design is also implemented, and the result is compared with the Shan and Faqiang converter. The efficiency of the converter is also tested.

Findings

The converter is providing a higher efficiency. The inductor current is also positive in both buck and boost mode. The robustness of the controller is better for a wide range of variation of input voltage because the output voltage remains almost constant. Therefore, this is very suitable for battery charging and PV module application.

Practical implications

For battery charging from PV module where voltage fluctuation is frequent.

Social implications

The authors can use household applications to charge the battery using PV module.

Originality/value

The converter design concept is new. Optimization is used to find the parameters of the controllers and is implemented in hardware design. The parameters obtained provide robustness in the converter performance.
How sexual and natural selection shape sexual size dimorphism: Evidence from multiple evolutionary scales
Authors: Littleford‐Colquhoun Bethan L. , Clemente Christofer , Thompson Graham , Cristescu Romane H. , Peterson Nicola , Strickland Kasha , Stuart‐Fox Devi , Frere Celine H.
Published: April 2019

Sexual size dimorphism (SSD) is pervasive across taxa and reflects differences in the effects of sexual and natural selection on body size between the sexes. However, disentangling the complex eco‐evolutionary interactions between these two mechanisms remains a major challenge for biologists.

Here, we combine macro‐evolutionary (between‐species), local evolutionary (between‐population) and fine‐scale evolutionary (within‐population) patterns of SSD to explore how sexual and natural selection interact and shape the evolution of SSD in Australian agamid lizards. Australian agamid lizards show substantial variation in SSD, ecological traits and species density making them an ideal study system to address this question.

At the between‐species level, population density, ecological generalism and mean species size significantly predict SSD variation; however, only ecological generalism was found to significantly explain variation in larger‐than‐average male‐biased SSD. At the population level, density positively correlated with SSD in native habitats, but not city park habitats. Last, agonistic behaviour acted as the primary driver of SSD at the within‐population level.

Our results indicate how sexual and natural selection can interact at different evolutionary scales, and show the importance of considering both selective mechanisms when investigating patterns of SSD.

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Rearing background and exposure environment together explain higher survival of aquaculture fish during a bacterial outbreak
Authors: Räihä Ville , Sundberg Lotta‐Riina , Ashrafi Roghaieh , Hyvärinen Pekka , Karvonen Anssi
Published: April 2019

Parasitic diseases represent one of the greatest challenges for aquaculture worldwide and there is an increasing emphasis on ecological solutions to prevent infections. One proposed solution is enriched rearing, where traditional stimulus‐poor rearing tanks are equipped with different types of structures to increase habitat complexity. Such spatial enrichment is known to increase survival of fish during parasite epidemics, but the underlying mechanisms are still unclear.

We studied whether enriched rearing affected infection of an important fish pathogen Flavobacterium columnare in young Atlantic salmon (Salmo salar) and sea‐migrating brown trout (Salmo trutta). First, we used natural bacterial exposures and multiple fish populations in a common garden experiment to address the role of host genetic background in effects of enriched rearing. Second, fish from standard and enriched rearing were experimentally exposed to controlled bacterial doses in standard and enriched environments in a full factorial design to explore the relative roles of rearing background and environment of exposure on survival of fish.

Enriched rearing significantly increased survival of fish during the natural bacterial outbreak. This effect was also fairly consistent and observed in eight of the ten fish populations. In the controlled exposure, fish exposed in enriched environment had higher survival regardless of their rearing background, suggesting a stronger impact of the environment on the disease progression. Additionally, the survival in the enriched environment was the highest among the fish of enriched rearing background, supporting the idea of their higher resistance.

Synthesis and applications. Our study suggests that the enhanced survival of fish in enriched rearing is a result of a combined effect of the environment and improved fish condition and, to a lesser degree, from host genetic background. This has important implications for when and how environmental enrichment should be applied. Overall, these results indicate that environmental enrichment has the potential to improve survival of fish during parasitic epidemics and thus reduce use of antibiotics in aquaculture.