bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacillus safensisFO-36b andBacillus pumilusSAFR-032: A Whole Genome Comparison of Two Spacecraft Assembly Facility Isolates
Authors: Tirumalai Madhan R , Stepanov Victor G. , Wünsche Andrea , Montazari Saied , Gonzalez Racquel O. , Venkateswaran Kasturi , Fox George. E.
Published: March 2018

Background

Bacillusstrains producing highly resistant spores have been isolated from cleanrooms and space craft assembly facilities. Organisms that can survive such conditions merit planetary protection concern and if that resistance can be transferred to other organisms, a health concern too. To further efforts to understand these resistances, the complete genome ofBacillus safensisstrain FO-36b, which produces spore resistant to peroxide and radiation was determined. The genome was compared to the complete genome ofB. pumilus SAFR-032, as well as draft genomes ofB. safensisJPL-MERTA-8-2 and the type strainB. pumilusATCC7061T. In addition, comparisons were made to 61 draft genomes that have been mostly identified as strains ofB. pumilusorB. safensis.

Results

The FO-36b gene order is essentially the same as that in SAFR-032 and otherB. pumilusstrains [1]. The annotated genome has 3850 open reading frames and 40 noncoding RNAs and riboswitches. Of these, 307 are not shared by SAFR-032, and 65 are also not shared by either MERTA or ATCC7061T. The FO-36b genome was found to have ten unique reading frames and two phage-like regions, which have homology with theBacillusbacteriophage SPP1 (NC_004166) andBrevibacillusphage Jimmer1 (NC_029104). Differing remnants of the Jimmer1 phage are found in essentially allsafensis/pumilusstrains. Seven unique genes are part of these phage elements. Comparison ofgyrAsequences from FO-36b, SAFR-032, ATCC7061T, and 61 other draft genomes separate the various strains into three distinct clusters. Two of these are subgroups ofB. pumiluswhile the other houses all theB. safensisstrains.

Conclusions

It is not immediately obvious that the presence or absence of any specific gene or combination of genes is responsible for the variations in resistance seen. It is quite possible that distinctions in gene regulation can change the level of expression of key proteins thereby changing the organism’s resistance properties without gain or loss of a particular gene. What is clear is that phage elements contribute significantly to genome variability. The larger comparison of multiple strains indicates that many strains named asB. pumilusactually belong to theB. safensisgroup.
LncRNAOIP5-AS1is overexpressed in undifferentiated oral tumors and integrated analysis identifies as a downstream effector of stemness-associated transcription factors
Authors: Arunkumar Ganesan , Anand Shankar , Raksha Partha , Dhamodharan Shankar , Prasanna Srinivasa Rao Harikrishnan , Subbiah Shanmugam , Murugan Avaniyapuram Kannan , Munirajan Arasambattu Kannan
Published: March 2018

Long non-coding RNAs (lncRNAs) play an important role in the regulation of key cellular processes in early development and in cancer. LncRNAOip5-as1facilitates stem cell self-renewal in mouse by sponging mmu-miR-7 and modulating NANOG level, yet its role in cancer is less understood. We analyzedOIP5-AS1expression in oral tumors and in TCGA datasets. We observed overexpression ofOIP5-AS1in oral tumors (P<0.001) and in tumors of epithelial origin from TCGA.OIP5-AS1expression was strongly associated with undifferentiated tumors (P=0.0038).In silicoanalysis showed miR-7 binding site is conserved in mouse and humanOIP5-AS1. However, humanNANOG3’-UTR lost the binding site for hsa-miR-7a-3. Therefore, we screened for other miRNAs that can be sponged byOIP5-AS1and identified six potential miRNAs and their downstream target genes. Expression analysis showed downregulation of miRNAs and upregulation of downstream target genes, particularly in undifferentiated tumors with high-level ofOIP5-AS1suggesting thatOIP5-AS1could post-transcriptionally modulate the downstream target genes. Further, systematic epigenomic analysis ofOIP5-AS1promoter revealed binding motifs for MYC, NANOG and KLF4 suggesting thatOIP5-AS1could be transactivated by stemness-associated transcription factors in cancer. Overexpression of OIP5-AS1 in undifferentiated oral tumors may confer poor prognosis through maintenance of cancer stemness.
Roles of Vitamin Metabolizing Genes in Multidrug-Resistant Plasmids of Superbugs
Authors: Chakraborty Asit Kumar
Published: March 2018

Superbug crisis has rocked this world with million deaths due to failure of potent antibiotics. Thousands mdr genes with hundreds of mutant isomers are generated. Small integrons and R-plasmids have combined with F’-plasmids creating a space for >10-20 of mdr genes that inactivate antibiotics in different mechanisms. Mdr genes are created to save bacteria from antibiotics because gut microbiota synthesize >20 vitamins and complex bio-molecules needed for >30000 biochemical reactions of human metabolosome. In other words, mdr gene creation is protected from both sides, intestinal luminal cells and gut bacteria in a tight symbiotic signalling system. We have proposed, to avert the crisis all vitamin metabolizing genes will be acquired in MDR- plasmids if we continue oral antibiotics therapy. Therefore, we have checked the plasmid databases and have detected thiamine, riboflavin, folate, cobalamine and biotin metabolizing enzymes in MDR plasmids. Thusvitgenes may mobilise recently into MDR-plasmids and are likely essential for gut microbiota protection. Analysis found thatcobandthigenes are abundant and likely very essential than other vit genes.
“It does not help to look young and dumb…”
Authors: Meinich Jenny , Sang Kate
Published: March 2018

Purpose

While age is receiving increased attention in the literature on workplace diversity, it remains under researched. Intergenerational contact and its relationship to ageism require further research to understand their mechanisms and impacts. The paper aims to discuss this issue.

Design/methodology/approach

Using semi-structured interviews in the Norwegian technical industry, this paper explores how generations are formed and how this influences intergenerational contact.

Findings

Through the lens of ageism, the findings reveal that generational stereotypes are strongly held by respondents, and may affect how members of the generations interact in the workplace. Further, the data demonstrate that both age and generation are socially constructed, and age discrimination is perceived by both older and younger workers.

Originality/value

The study has relevance for managers who are overseeing organizations with considerable age differences.
Endogamy and income in native couples: the case of Finland
Authors: Härtull Camilla , Saarela Jan
Published: March 2018

Purpose

The purpose of this paper is to study two native and equal population groups, Finnish speakers and Swedish speakers in Finland, to examine whether there is income variation across couples that differ on ethno-linguistic composition, and if such variation can be attributed to differences in education, educational homogamy and other observable characteristics.

Design/methodology/approach

Using detailed register-based household data, the authors estimate OLS models to compare endogamous and exogamous couples with respect to income of the man, the woman, and both partners, respectively.

Findings

Endogamous Swedish-speaking couples are found to have on average 25 per cent higher income than other couples. The advantage is not related to differences in educational homogamy, but primarily to man’s income, and roughly half of the income difference is explained by the higher educational level of Swedish-speaking men in endogamous couples. Although women in endogamous Swedish-speaking couples are higher educated than other women, and there is a higher degree of educational homogamy in these couples, their education has only a modest bearing on the income differential.

Originality/value

In the case of Finland, educational homogamy does not affect income variation across native couples that differ on ethno-linguistic composition. Endogamous mate selection seems to increase economic inequality, uphold gender inequality, and help the native minority group in sustaining its own community.
Managers’ retention decisions regarding young intermediate-level educated employees
Authors: Buers Corine , Karpinska Kasia , Schippers Joop
Published: March 2018

Purpose

The purpose of this paper is to investigate the opportunities in the labour market for young employees with intermediate-level education by studying which young employees are most likely to be retained and under what conditions managers favour retention.

Design/methodology/approach

Retention decisions are examined by combining a vignette experiment and a survey study. Hypothetical profiles of 252 young employees were rated on their retention desirability by 21 managers, each working in a different organisation. Information on the managers’ characteristics and their organisations were collected in a survey.

Findings

Managers are generally not inclined to suggest retention. Their decisions are highly dependent on their own characteristics and organisational factors, even when young employees perform well and display desirable work-related behaviour.

Research limitations/implications

While the small scale and explorative nature of this study limit its generalisability, this paper highlights the importance of combining information on employees, the organisation and managers; when studying (early) careers and employment decisions.

Practical implications

This study suggests that job retention is only in part within an individual’s control, and the future efforts to combat youth unemployment need to account for organisational and managerial characteristics.

Originality/value

The focus on the employer’s perspective is new to research on early careers, making it a starting point for further lines of exploration. Further, this study provides a comprehensive insight into factors that influence managers’ retention decisions by combining three sets of factors in a single research design.
State dependence of labour force participation of married Australian women
Authors: Cai Lixin
Published: March 2018

Purpose

The purpose of this paper is to enhance the understanding of labour force participation behaviour of married Australian women, with a focus on identifying the sources of observed inter-temporal labour force participation persistence.

Design/methodology/approach

A dynamic Probit model is applied to the Household, Income and Labour Dynamics in Australia (HILDA) Survey, a national representative panel survey of Australian households. The model used accounts for observed and unobserved individual heterogeneity and serially correlated transitory shocks to labour supply.

Findings

The results show that both observed and unobserved individual heterogeneity contributes to observed inter-temporal persistence of labour force participation of married Australian women, but the persistence remains even after controlling for these factors. It is also found that failing to control for serially correlated unobserved transitory shocks would lead to underestimation of genuine state dependence of labour force participation; and that state dependence of labour force participation varies with age, education, health, immigration status and the number of children under the school age.

Originality/value

This study adds to the international literature on labour force dynamics of women by providing Australian empirical evidence and through a flexible modelling framework. The result that there exists genuine positive state dependence in married Australian women’s labour force participation suggests that policy intervention that increases married women’s labour supply would have a long-lasting effect.
The impact of HR outsourcing and strategic HR integration on the HR-to-employee ratio
Authors: Szierbowski-Seibel Klaas , Kabst Ruediger
Published: March 2018

Purpose

Two simultaneous trends have arisen in the field of HRM: the development of the human resource (HR) function toward a more strategic, value adding unit and the trend of HR outsourcing (HRO). Opinions are divided in the field of HRM research regarding the interdependences between these two trends and whether the HR function has a positive or negative effect. Therefore, the purpose of this paper is to examine the triangular relationship among strategic HR integration, the HR-to-employee ratio and HRO.

Design/methodology/approach

This study analyses data from three large evaluations conducted in 14 European countries and compares the results obtained from the 2000, 2005 and 2010 Cranet survey waves. For the hypotheses, a multilevel regression design was used.

Findings

The results allow concluding that HRO supports the professionalization of the HR function in an effort to make it a strategic asset.

Research limitations/implications

This study extends prior understandings of the theoretical perspective on HRO and its organizational impact. The sample is nested within 14 European countries and influenced by cultural aspects and institutional factors. These influences could be an exciting avenue for further research.

Practical implications

This paper includes important implications for HR practitioners. The results support a rather optimistic view of the HR function regarding its relationship with HRO and the latter’s impact on the HR-to-employee ratio and strategic HR integration.

Originality/value

The study answers the question: has HRO downsized internal HR staff over the past decade, and how is it related to the strategic integration of the HR function? In this context, this study analyses Cranet data to contribute to the discussion on the development of strategic HR integration and the impact of HRO on such efforts. Moreover, the study examines the influence of HRO on internal HR staff based on the theoretical framework of the resource-based view.
Long-term scarring effect of neither working nor studying
Authors: Andersson Fredrik W. , Gullberg Brännstrom Susanne , Mörtvik Roger
Published: March 2018

Purpose

It is increasingly important to study labour market outcomes for people who are not in employment, education, or training (NEET). Where most studies focus solely on young people, the purpose of this paper is to include both younger and older NEETs to find out if there is any long-term scarring effect, and if the effect is different between these two groups.

Design/methodology/approach

This study uses a twin-based estimation method for the first time to measure the long-term effect of economic inactivity on income. The analysis is based on biological twins, in order to control for individuals’ unobservable heterogeneity. It is assumed that twins are similar to each other and the only unobservable heterogeneity is at the family level. Register-based data from Statistics Sweden is used.

Findings

The result indicates a significant negative income effect for those who have been in NEET, and is larger for those who have been in NEET for several consecutive periods of time. Individuals who were in NEET during 2001-2003 had on average 62 per cent lower income compared with their twin in 2011. The corresponding number for individuals who were in NEET for just one period was 33 per cent. Hence, time in NEET reduces income. The results show that the long-term scarring effect is not affected by age.

Originality/value

This study utilises for the first time a twin-based estimation method to measure the long-term effect of inactivity. Most studies focus solely on young people, but the authors also include an older group of people.
The extent of segmental reporting and its value relevance: cross-country evidence
Authors: Mardini Ghassan H. , Tahat Yasean A. , Power David M.
Published: March 2018

Purpose

The purpose of this paper is to examine the extent of segmental reporting disclosure and its value relevance to a sample of Qatari and Jordanian listed companies following the implementation review of the International Financial Reporting Standard (IFRS) 8. This was the first standard to be subjected to a post-implementation review. Annual reports are initially analyzed to investigate the level of segmental information that was published by companies in these two countries.

Design/methodology/approach

Using the Ohlson (1995) model, the study employs regression analysis to test the hypotheses relating to the value relevance of the segmental disclosures uncovered. In addition, one-way ANOVA and Kruskal-Wallis tests are used to investigate any variation in segmental reporting among sectors.

Findings

The findings indicate that the amount of segmental information disclosed by the sample firms differs across sectors. Moreover, the segmental information provided (including the number of segments and the amounts of disclosure) is value relevant and can explain the variations in firms’ share prices.

Practical implications

The results of the current investigation have implications for policy makers, including the International Accounting Standards Board, as well as for accounting regulators in Jordan and Qatar. They suggest that the segmental disclosures supplied under IFRS 8 are value relevant for equity prices in a developing country context. Compliance with IFRS 8 should thus be monitored to ensure that all firms provide the segmental disclosures that they are meant to supply under the terms of the standard.

Originality/value

This paper is one of the few to provide empirical evidence on the role of segmental reporting following the post-implementation review that was conducted for IFRS 8.
How can century-old architectural hierarchies for the design of public libraries be re-interpreted and re-used?
Authors: Prizeman Oriel , Jones Christopher Bernard , Parisi Mariangela , Pezzica Camilla
Published: March 2018

Purpose

The purpose of this paper is to describe a novel approach to inform heritage conservation based on the effective integration of documentation-based research with advanced survey methods for the creation of a sharable historic building information modelling (HBIM) objects database, specifically oriented to the study of Carnegie libraries whose designs in the USA and the UK were somewhat systematised by early principles of standardisation. The aim is to generate an exemplar developing new methodologies for the salvage, re-use and re-invigoration of shared inherited public buildings which have many common and standardized features.

Design/methodology/approach

This project will also involve the collaboration of conservation practice and digital recording together with library history. Digital laser scanning and structure from motion will be used together with archival documents to accurately build an information-rich framework for CAD and building information modelling applications.

Findings

By providing the base elements for the semi-automatic generation of a wide variety of morphological typologies and construction elements, this work ultimately promotes a shift towards the implementation of HBIM to support the conservation, maintenance and management of a high number of insufficiently protected public buildings from the turn of the last century.

Originality/value

The intention is that the resulting multidimensional parametric object library will provide suitable support for the faster generation of enriched 3D historic models and ultimately support the preservation of a large proportion of the huge but threatened public library building heritage in the UK and USA.
An exploratory analysis of corporate social responsibility reporting in US pharmaceutical companies
Authors: Cook Lori , LaVan Helen , Zilic Ivana
Published: March 2018

Purpose

The purpose of this paper is to compare “how we see ourselves” vs “how others see us” when communicating corporate social responsibility (CSR) activities in US pharmaceutical companies.

Design/methodology/approach

Data were collected as follows: CSR reports from the companies themselves and Business Press reports from the Lexis-Nexis database. NVivo content analysis was used to compare CSR communication by companies and the Business Press. This analysis was comprised of almost 10 million words. Comparisons of Carroll’s framework, including the economic, legal, ethical, and philanthropic categories between CSR reports and the Business Press, were done. Additional analysis was done to discern individual, organizational, and societal patterns of communications. Return on assets was computed for companies that have formal CSR reports and those that do not.

Findings

The analysis of documents containing almost 10 million words allowed the following conclusions: companies communicate more about their economic and philanthropic activities, and the Business Press communicates more about their legal and ethical activities. The companies and the Business Press communicated similarly about individual CSR. The organization communicated more about organizational topics, and the Business Press communicated less about societal topics.

Originality/value

This paper makes both substantive and methodological contributions. Its substantive contribution allows an understanding of what pharmaceutical companies need to do to fully communicate their CSR activities. Its methodological contribution is in suggesting that content analysis be used in understanding communication patterns. A levels of analysis approach allowed the discernment of individual-oriented, organizational, and societal-oriented communication patterns.
The art of strategic improvisation
Authors: Falkheimer Jesper , Sandberg Katarina Gentzel
Published: March 2018

Purpose

The purpose of this paper is to describe strategic improvisation, a contemporary concept and approach based on the creative arts and organizational crisis theory, as a valuable approach for communication professionals. Strategic improvisation combines the need for planning and structure with creative action, and is a normative idea of how to work in an efficient way.

Design/methodology/approach

The concept is developed in a collaborative project between a major Swedish communications agency and a university scholar. The empirical foundation consists of 25 qualitative interviews with a strategic selection of successful communication professionals, identified as typical strategic improvisers.

Findings

An analysis of the interviews led to 11 defining patterns or themes typical for strategic improvisation and strategic improvisers. The interviews and the theoretical framework is the foundation of a communication model. Strategic improvisation is defined as a situational interpretation within a given framework. The model has three interconnected parts: a clear framework (composition), a professional interpretation (interpretation) and a situational adaptation based on given possibilities and conditions (improvisation).

Research limitations/implications

This is not a peer reviewed paper, but a paper in the section “In Practice,” directed toward communication professionals.

Originality/value

The ideas and model are connected to theories of improvisation, especially in music, which is rare in the field of communication management, and developed in a collaborative project between practice and research.
How focusing positively on errors can help organizations become more communicative
Authors: Simonsson Charlotte , Heide Mats
Published: March 2018

Purpose

The purpose of this paper is to gain new knowledge of how organizational errors can be used to early detect signals of impending crises and thereby develop internal crisis communication. Three communication processes – organizational culture, leadership and learning – that are particularly important for the development of internal crisis communication are focused. The paper also discusses what kind of learning error management supports, and suggests how crisis communication as a practice can be developed. The thesis is that intensified work of improving internal crisis communication is a vital step of becoming a communicative organization, where all coworkers are understood and act as strategic communicators.

Design/methodology/approach

This empirical study is part of a three-year research project on internal crisis communication within a Swedish university hospital. This paper is based on a sub-study with 37 qualitative semi-structured interviews with nurses, physicians, managers and crisis management specialists within the hospital.

Findings

The paper offers knowledge about how internal crisis communication can be developed by focusing on errors as resource to anticipate a crisis and as material for organizational learning. Coworkers are mainly focused in the article and are seen as important sources and strategic communicators. It is further emphasized that error management is not a matter of technological solutions, but rather a question of communicative aspects of leadership and organizational culture.

Practical implications

It is suggested that initiatives to develop internal crisis communication is an important step for organizations in becoming communicative organizations, and communication professionals have an important role to facilitate this development.

Originality/value

This paper gives a new understanding of internal crisis communication and the importance of leadership and culture.
It’s My Time: applying the health belief model to prevent cervical cancer among college-age women
Authors: Sundstrom Beth , Brandt Heather M. , Gray Lisa , Young Pierce Jennifer
Published: March 2018

Purpose

Cervical cancer (CxCa) incidence and mortality remain unacceptably high in South Carolina, USA, presenting an ideal opportunity for intervention. To address this need, Cervical Cancer-Free South Carolina developed an academic-community partnership with researchers and students at a public university to design, implement, and evaluate a theory-based CxCa communication campaign, It’s My Time. The paper aims to discuss this issue.

Design/methodology/approach

The goal of this campaign was to decrease CxCa by increasing human papillomavirus (HPV) vaccination and appropriate screening. This paper describes the development, implementation, and evaluation of a successful theory-based CxCa prevention communication campaign for college women based on formative audience research and targeted messages delivered to audience segments through new and traditional communication channels. The health belief model (HBM) served as a theoretical framework for the campaign throughout development, implementation, and evaluation.

Findings

This campaign demonstrated the effectiveness of the HBM to address CxCa prevention, including HPV vaccine acceptability. The campaign aimed to increase perceptions of susceptibility, which were low, by emphasizing that HPV is a sexually transmitted infection. A community-based grassroots approach to addressing disparities in CxCa prevention increased benefits and decreased barriers. Social media emerged as a particularly appropriate platform to disseminate cues to action. In total, 60 percent of participants who responded to an anonymous web-based survey evaluation indicated that they received the HPV vaccine as a result of campaign messages.

Originality/value

This paper offers practical suggestions to campaign planners about building academic-community partnerships to develop theory-based communication campaigns that include conducting formative research, segmenting target audiences, engaging with young people, and incorporating social media.
Crafting employee trust: from authenticity, transparency to engagement
Authors: Jiang Hua , Luo Yi
Published: March 2018

Purpose

The purpose of this paper is to propose and test a model examining how three influential organizational factors – authentic leadership, transparent organizational communication, and employee engagement – are linked to employee trust.

Design/methodology/approach

This study conducted an online survey on a random sample of 391 employees across different industry sectors in the USA.

Findings

Authentic leadership, transparent organizational communication, and employee engagement directly and significantly influenced the level of trust that employees have toward their organizations. Authentic leadership indirectly impacted employee engagement through transparent organizational communication. Authentic leadership also indirectly affected employee trust via the presence of transparent organizational communication and employee engagement.

Practical implications

The study informs communication managers and organizational leaders with the importance of integrating authentic leadership and transparent communication skills, strategies, and tactics in various training and mentoring workshops. Creating a motivating, nurturing, and transparent organizational environment contributes to employee engagement and trust.

Originality/value

This study examines the drivers of employee trust by testing the effects of employee engagement, authentic leadership, and transparent organizational communication.
Volatility spillover from crude oil and gold to BRICS equity markets
Authors: Pandey Vikas , Vipul Vipul
Published: March 2018

Purpose

The purpose of this paper is to investigate the volatility spillover from crude oil and gold to the BRICS stock markets, after removing the effect of co-movement of prices of crude oil and gold.

Design/methodology/approach

Three multivariate GARCH models (dynamic conditional correlation, constant conditional correlation, and Baba, Engle, Kraft and Kroner) are used to capture the dynamic relationship between the crude oil and gold returns. The innovations from gold and oil are orthogonalized, and the EGARCH model is employed for the spillover analysis. The influences of oil price shocks and gold price shocks are tested on the returns of each of the BRICS equity markets.

Findings

There is evidence of volatility spillover from both the crude oil and gold to the BRICS stock markets. A sub-sample analysis suggests that the volatility spillover from gold was not significant before the financial crisis of 2008, but became significant post-crisis. The volatility asymmetry, which was not significant before the crisis, also became significant after it.

Originality/value

This study examines the volatility spillover to the BRICS stock markets from crude oil and gold, after accounting for the co-movement in their prices. It can help equity investors to judge whether gold can provide incremental diversification benefit, if used in conjunction with crude oil. The study also provides insights into the changes caused by the 2008 financial crisis on this volatility spillover mechanism.
The link between mergers and acquisitions and innovation
Authors: Dezi Luca , Battisti Enrico , Ferraris Alberto , Papa Armando
Published: March 2018

Purpose

The link between mergers and acquisitions (M&A) and innovation has been analysed in both corporate finance studies and the innovation literature. Despite this attention and the practical evidence that highlights different connections between these two terms, there is a need to investigate the latest trends with regard to these important topics, and to put a particular focus on the emerging paradigm of open innovation. Thus, this paper aims to provide a systematic literature review (SLR) about the relationship between M&As and the concept of innovation in the current scenario.

Design/methodology/approach

Through an SLR from 2012 to June 2017, 55 papers have been identified and analysed to give a better understanding of the motivations and the methodologies adopted in past studies.

Findings

This paper identifies various conceptual and research methodological characteristics of studies that have connected, directly or indirectly, M&As and innovation in recent years. In addition, the results highlight a scarcity of studies that explicitly or implicitly refer to the open innovation paradigm, marking only a partial understanding of this emerging phenomenon.

Originality/value

This paper improves the knowledge on the link between extraordinary corporate transactions and innovation, and it highlights that a clear consensus, particularly regarding the open innovation paradigm, is lacking. Thus the authors propose that future studies should carefully evaluate M&As by following the open innovation approach.
Kinetic study and characterization of a platinum electrode/sensitive membrane for malachite green detection
Authors: Ghodbane Ilhem , Kherrrat Rochdi , Zougar Saida , Lamari Rim , Haddadji Redouane , Medjram Mohamed Saleh
Published: March 2018

Purpose

The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution.

Design/methodology/approach

The present sensor consists in the spatial coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (polyvinylchloride [PVC]) and a plasticizer (dioctyl phthalate [DOP]). Several techniques have been used to characterize this sensor: the cyclic voltammetry, the electrochemical impedance spectroscopy and the optical microscopy. The sensibility, the selectivity and the kinetic study of a modified platinum electrode have been evaluated by cyclic voltammetry.

Findings

The obtained results reveal the possibility of a linear relationship between the current of reduction peaks and MG concentration. A linear response was obtained in a wide-concentration range that stretches from 10−5to 10−13mol L−1, with a good correlation coefficient (0.976) and a good detection limit of 5.74 × 10−14mol L−1(a signal-to-noise ratio of 3). In addition, the voltammetric response of modified electrode can be enhanced by adding a layer of Nafion membrane. Under this optimal condition, a linear relationship was obtained, with a correlation coefficient of 0.986 and a detection limit of 1.92 × 10−18mol L−1.

Originality/value

In the present research, a convenient, inexpensive and reproducible method for the detection of MG was developed. The developed sensor is capable of competing against the conventional techniques in terms of speed, stability and economy.
Motivic and real étale stable homotopy theory
Authors: Bachmann Tom
Published: March 2018

Let$S$be a Noetherian scheme of finite dimension and denote by$\unicode[STIX]{x1D70C}\in [\unicode[STIX]{x1D7D9},\mathbb{G}_{m}]_{\mathbf{SH}(S)}$the (additive inverse of the) morphism corresponding to$-1\in {\mathcal{O}}^{\times }(S)$. Here$\mathbf{SH}(S)$denotes the motivic stable homotopy category. We show that the category obtained by inverting$\unicode[STIX]{x1D70C}$in$\mathbf{SH}(S)$is canonically equivalent to the (simplicial) local stable homotopy category of the site$S_{\text{r}\acute{\text{e}}\text{t}}$, by which we mean thesmallreal étale site of$S$, comprised of étale schemes over$S$with the real étale topology. One immediate application is that$\mathbf{SH}(\mathbb{R})[\unicode[STIX]{x1D70C}^{-1}]$is equivalent to the classical stable homotopy category. In particular this computes all the stable homotopy sheaves of the$\unicode[STIX]{x1D70C}$-local sphere (over$\mathbb{R}$). As further applications we show that$D_{\mathbb{A}^{1}}(k,\mathbb{Z}[1/2])^{-}\simeq \mathbf{DM}_{W}(k)[1/2]$(improving a result of Ananyevskiy–Levine–Panin), reprove Röndigs’ result that$\text{}\underline{\unicode[STIX]{x1D70B}}_{i}(\unicode[STIX]{x1D7D9}[1/\unicode[STIX]{x1D702},1/2])=0$for$i=1,2$and establish some new rigidity results.
Automated Discovery of Product Feature Inferences Within Large-Scale Implicit Social Media Data
Authors: Tuarob Suppawong , Lim Sunghoon , Tucker Conrad S.
Published: March 2018

Recently, social media has emerged as an alternative, viable source to extract large-scale, heterogeneous product features in a time and cost-efficient manner. One of the challenges of utilizing social media data to inform product design decisions is the existence of implicit data such as sarcasm, which accounts for 22.75% of social media data, and can potentially create bias in the predictive models that learn from such data sources. For example, if a customer says “I just love waiting all day while this song downloads,” an automated product feature extraction model may incorrectly associate a positive sentiment of “love” to the cell phone's ability to download. While traditional text mining techniques are designed to handle well-formed text where product features are explicitly inferred from the combination of words, these tools would fail to process these social messages that include implicit product feature information. In this paper, we propose a method that enables designers to utilize implicit social media data by translating each implicit message into its equivalent explicit form, using the word concurrence network. A case study of Twitter messages that discuss smartphone features is used to validate the proposed method. The results from the experiment not only show that the proposed method improves the interpretability of implicit messages, but also sheds light on potential applications in the design domains where this work could be extended.
An Algorithm for Rigid-Body Angular Velocity and Attitude Estimation Based on Isotropic Accelerometer Strapdowns
Authors: Zou Ting , Angeles Jorge
Published: March 2018

A novel algorithm for the estimation of rigid-body angular velocity and attitude—the most challenging part of pose-and-twist estimation—based on isotropic accelerometer strapdowns, is proposed in this paper. Quaternions, which employ four parameters for attitude representation, provide a compact description without the drawbacks brought about by other representations, for example, the gimbal lock of Euler angles. Within the framework of quaternions for rigid-body angular velocity and attitude estimation, the proposed methodology automatically preserves the unit norm of the quaternion, thus improving the accuracy and efficiency of the estimation. By virtue of the inherent nature of isotropic accelerometer strapdowns, the centripetal acceleration is filtered out, leaving only its tangential counterpart, to be estimated and updated. Meanwhile, using the proposed integration algorithm, the angular velocity and the quaternion, which are dependent only on the tangential acceleration, are calculated and updated at appropriate sampled instants for high accuracy. This strategy, which brings about robustness, allows for relatively large time-step sizes, low memory demands, and low computational complexity. The proposed algorithm is tested by simulation examples of the angular velocity and attitude estimation of a free-rotating brick and the end-effector of an industrial robot. The simulation results showcase the algorithm with low errors, as estimated based on energy conservation, and high-order rate of convergence, as compared with other algorithms in the literature.
A Semi-Infinite Strip Pressed Against an Elastic Half-Plane With Frictional Slip
Authors: Adams George G.
Published: March 2018

The subject of this investigation is the plane strain elasticity problem of a finite width semi-infinite strip with its end pressed against a half-plane of the same material with friction. From the existing integral equation solution for a perfect bond, it is shown that the length of the zone of frictional slip and the value of the slip displacement can both be inferred. It is further shown how this method allows a finite element stress analysis of a structure, obtained with the simple assumption of a perfect bond, to be used instead of the more complicated finite element structural analysis with frictional slip. Nonetheless, the results of this simpler finite element analysis can be used to infer the length of the frictional slip zone and the magnitude of the slip displacement. It is expected that this method will be valuable in the analysis of the mechanics of fretting. Damage due to fretting fatigue is initiated due to frictional slip near the edges of the interface between two connected materials. The stress analysis of structures, which includes these frictional slip zones, is considerably more complicated than it is for a perfect bond, often making it impractical to include in a comprehensive finite element model of the complete structure. Thus, the methodology used in this paper should allow the size of the frictional slip zones and the frictional slip displacements to be inferred directly from the stress analysis for a perfect bond.
Graphical Hopf Bifurcation of a Filippov HTLV-1 Model With Delay in Cytotoxic T Cells Response
Authors: Shamsara Elham , Afsharnezhad Zahra , Javidmanesh Elham
Published: March 2018

In this paper, we present a discontinuous cytotoxic T cells (CTLs) response for HTLV-1. Moreover, a delay parameter for the activation of CTLs is considered. In fact, a system of differential equation with discontinuous right-hand side with delay is defined for HTLV-1. For analyzing the dynamical behavior of the system, graphical Hopf bifurcation is used. In general, Hopf bifurcation theory will help to obtain the periodic solutions of a system as parameter varies. Therefore, by applying the frequency domain approach and analyzing the associated characteristic equation, the existence of Hopf bifurcation by using delay immune response as a bifurcation parameter is determined. The stability of Hopf bifurcation periodic solutions is obtained by the Nyquist criterion and the graphical Hopf bifurcation theorem. At the end, numerical simulations demonstrated our results for the system of HTLV-1.
Numerical Prediction of Cyclic Variability in a Spark Ignition Engine Using a Parallel Large Eddy Simulation Approach
Authors: Ameen Muhsin M. , Mirzaeian Mohsen , Millo Federico , Som Sibendu
Published: March 2018

Cycle-to-cycle variability (CCV) is detrimental to IC engine operation and can lead to partial burn, misfire, and knock. Predicting CCV numerically is extremely challenging due to two key reasons. First, high-fidelity methods such as large eddy simulation (LES) are required to accurately resolve the in-cylinder turbulent flow field both spatially and temporally. Second, CCV is experienced over long timescales and hence the simulations need to be performed for hundreds of consecutive cycles. Ameen et al. (2017, “Parallel Methodology to Capture Cyclic Variability in Motored Engines,” Int. J. Engine Res., 18(4), pp. 366–377.) developed a parallel perturbation model (PPM) approach to dissociate this long time-scale problem into several shorter time-scale problems. This strategy was demonstrated for motored engine and it was shown that the mean and variance of the in-cylinder flow field was captured reasonably well by this approach. In the present study, this PPM approach is extended to simulate the CCV in a fired port-fuel injected (PFI) spark ignition (SI) engine. The predictions from this approach are also shown to be similar to the consecutive LES cycles. It is shown that the parallel approach is able to predict the coefficient of variation (COV) of the in-cylinder pressure and burn rate-related parameters with sufficient accuracy, and is also able to predict the qualitative trends in CCV with changing operating conditions. It is shown that this new approach is able to give accurate predictions of the CCV in fired engines in less than one-tenth of the time required for the conventional approach of simulating consecutive engine cycles.
Thesaurus-Guided Text Analytics Technique for Capability-Based Classification of Manufacturing Suppliers
Authors: Sabbagh Ramin , Ameri Farhad , Yoder Reid
Published: March 2018

Manufacturing capability (MC) analysis is a necessary step in the early stages of supply chain formation. In the contract manufacturing industry, companies often advertise their capabilities and services in an unstructured format on the company website. The unstructured capability data usually portray a realistic view of the services a supplier can offer. If parsed and analyzed properly, unstructured capability data can be used effectively for initial screening and characterization of manufacturing suppliers specially when dealing with a large pool of suppliers. This work proposes a novel framework for capability-based supplier classification that relies on the unstructured capability narratives available on the suppliers' websites. Four document classification algorithms, namely, support vector machine (SVM ), Naïve Bayes, random forest, and K-nearest neighbor (KNN) are used as the text classification techniques. One of the innovative aspects of this work is incorporating a thesaurus-guided method for feature selection and tokenization of capability data. The thesaurus contains the formal and informal vocabulary used in the contract machining industry for advertising manufacturing capabilities. A web-based tool is developed for the generation of the concept vector model associated with each capability narrative and extraction of features from the input documents. The proposed supplier classification framework is validated experimentally through forming two capability classes, namely, heavy component machining and difficult and complex machining, based on real capability data. It was concluded that thesaurus-guided method improves the precision of the classification process.
Frontal Plane Tibiofemoral Alignment is Strongly Related to Compartmental Knee Joint Contact Forces and Muscle Control Strategies During Stair Ascent
Authors: Bennett Hunter J. , Weinhandl Joshua T. , Fleenor Kristina , Zhang Songning
Published: March 2018

Static frontal plane tibiofemoral alignment is an important factor in dynamic knee alignment and knee adduction moments (KAMs). However, little is known about the relationship between alignment and compartment contact forces or muscle control strategies. The purpose of this study was to estimate medial (MCF) and lateral (LCF) compartment knee joint contact forces and muscle forces during stair ascent using a musculoskeletal model implementing subject-specific knee alignments. Kinematic and kinetic data from 20 healthy individuals with radiographically confirmed varus or valgus knee alignments were simulated using alignment specific models to predict MCFs and LCFs. Muscle forces were determined using static optimization. Independent samples t-tests compared contact and muscle forces between groups during weight acceptance and during pushoff. The varus group exhibited increased weight acceptance peak MCFs, while the valgus group exhibited increased pushoff peak LCFs. The varus group utilized increased vasti muscle forces during weight acceptance and adductor forces during pushoff. The valgus group utilized increased abductor forces during pushoff. The alignment-dependent contact forces provide evidence of the significance of frontal plane knee alignment in healthy individuals, which may be important in considering future knee joint health. The differing muscle control strategies between alignments detail-specific neuromuscular responses to control frontal plane knee loads.
Beneficial Effects of Exercise on Subendothelial Matrix Stiffness Are Short-Lived
Authors: Kohn Julie C. , Bordeleau François , Miller Joseph , Watkins Hannah C. , Modi Shweta , Ma Jenny , Azar Julian , Putnam David , Reinhart-King Cynthia A.
Published: March 2018

Aerobic exercise helps to maintain cardiovascular health in part by mitigating age-induced arterial stiffening. However, the long-term effects of exercise regimens on aortic stiffness remain unknown, especially in the intimal extracellular matrix layer known as the subendothelial matrix. To examine how the stiffness of the subendothelial matrix changes following exercise cessation, mice were exposed to an 8 week swimming regimen followed by an 8 week sedentary rest period. Whole vessel and subendothelial matrix stiffness were measured after both the exercise and rest periods. After swimming, whole vessel and subendothelial matrix stiffness decreased, and after 8 weeks of rest, these values returned to baseline. Within the same time frame, the collagen content in the intima layer and the presence of advanced glycation end products (AGEs) in the whole vessel were also affected by the exercise and the rest periods. Overall, our data indicate that consistent exercise is necessary for maintaining compliance in the subendothelial matrix.