bluuebunny/crossref_metadata_2025_split huggingface dataset:
The BMP2/4 ortholog Dpp functions as an inter-organ signal that regulates developmental timing inDrosophila
Authors: Setiawan Linda , Woods Alexis L. , Hariharan Iswar K. 
Published: August 2017

AbstractFor many organisms, developmental transitions are triggered by a neuroendocrine axis and are contingent upon multiple organs achieving sufficient growth and maturation. How the status of peripheral organs is communicated to the neuroendocrine axis is not known. InDrosophilalarvae, metamorphosis is triggered by the steroid hormone ecdysone, secreted by the prothoracic gland (PG). Here we show that the BMP2/4 ortholog Dpp, which regulates growth and patterning of larval imaginal discs, also functions as a systemic signal to regulate developmental timing. Dpp from peripheral tissues, mostly imaginal discs, can reach the PG and inhibit ecdysone biosynthesis. As the discs grow, Dpp signaling decreases in the PG, thus alleviating the inhibition of ecdysone biosynthesis, and permitting entry into metamorphosis. We suggest that if a tissue can trap more morphogen locally as it grows and matures, then circulating levels of morphogen can provide a systemic readout of organ size and maturation.One Sentence SummaryDpp functions as a long-range endocrine signal between peripheral tissues and the prothoracic gland to regulate developmental timing inDrosophila.
Modeling of CPACS-based fuselage structures using Python
Authors: Walther Jan-Niclas , Petsch Michael , Kohlgrüber Dieter 
Published: August 2017

Purpose
The purpose of this paper is to present some of the key achievements. At DLR, a sophisticated interdisciplinary aircraft design process is being developed, using the CPACS data format (Nagel et al., 2012; Scherer and Kohlgrüber, 2016) as a means of exchanging results. Within this process, TRAFUMO (Scherer et al., 2013) (transport aircraft fuselage model), built on ANSYS and the Python programming language, is the current tool for automatic generation and subsequent sizing of global finite element fuselage models. Recently, much effort has gone into improving the tool performance and opening up the modeling chain to further finite element solvers.

Design/methodology/approach
Much functionality has been shifted from specific routines in ANSYS to Python, including the automatic creation of global finite element models based on geometric and structural data from CPACS and the conversion of models between different finite element codes. Furthermore, a new method for modeling and interrogating geometries from CPACS using B-spline surfaces has been introduced.

Findings
Several new modules have been implemented independently with a well-defined central data format in place for storing and exchanging information, resulting in a highly extensible framework for working with finite element data. The new geometry description proves to be highly efficient while also improving the geometric accuracy.

Practical implications
The newly implemented modules provide the groundwork for a new all-Python model generation chain, which is more flexible at significantly improved runtimes. With the analysis being part of a larger multidisciplinary design optimization process, this enables exploration of much larger design spaces within a given timeframe.

Originality/value
In the presented paper, key features of the newly developed model generation chain are introduced. They enable the quick generation of global finite element models from CPACS for arbitrary solvers for the first time.
Common computational model for coupling panel method with finite element method
Authors: Goetzendorf-Grabowski Tomasz , Mieloszyk Jacek 
Published: August 2017

Purpose
Conceptual and preliminary aircraft concepts are getting mature earlier in the design process, than ever before. To achieve that advanced level of maturity, multiple multidisciplinary analyses have to be done, often with usage of numerical optimization algorithms. This calls for right tools that can handle such a demanding task. Often the toughest part of a modern design is handling an aircraft’s computational models used for different analysis. Transferring geometry and loads from one program to another, or modifying internal structure, takes time and is not productive. Authors defined the concept of a common computational model (CCM), which couples programs from different aerospace scientific disciplines. Data exchange between the software components is compatible, and multidisciplinary analysis can be automated to high degree, including numerical optimization.

Design/methodology/approach
The panel method was applied to aerodynamic analysis and was coupled with open-source FEM code within one computational process.

Findings
The numerical results proved the effectiveness of developed methodology.

Practical implications
Developed software can be used within the design process of a new aircraft.

Originality/value
This paper presents an original approach for advanced numerical analysis, as well as for multidisciplinary optimization of an aircraft. The presented results show possible applications.
An exploration of gender, interlocking directorates, and corporate performance
Authors: O’Hagan Sean B. 
Published: August 2017

PurposeThe purpose of this study is to explore the impact that women who sit on boards of directors, as well as women that are part of an interlocking directorate, have on corporate performance. The investigation is placed within the literature on human capital theory and resource dependency as an argument for gender diversity and boards of directors.Design/methodology/approachA director data set for over 32,000 firms based in the USA, composed of 6,218 women and 54,932 men, is utilized. From this, regression and network analysis were utilized.FindingsIt is found that female directors’ participation in interlocking directorates translates into greater corporate performance when compared to simply examining female representation on boards of directors. Additionally, women involved in interlocks translated into greater corporate performance when compared to men. These results support the resource dependency approach.Practical/implicationsResults of this study suggest that when considering female directors, corporate performance is enhanced when female directors already sit on the boards of other firms.Originality/valueThis study highlights external network connections to differentiate between human capital theory and resource dependency as an argument for gender diversity and boards of directors.
An integrated strategy for fleet maintenance planning
Authors: Rawat Manish , Lad Bhupesh Kumar 
Published: August 2017

Purpose
Conventionally, fleet maintenance decisions are made based on the level of repair (LOR) analysis. A general assumption made during LOR analysis is the consideration of the lifetime distribution with constant failure rate (CFR). However, industries do use preventive maintenance (PM) to extend the life of such components, which in turn may affect the LOR decisions such as repair/move/discard. The CFR assumption does not allow the consideration of effect of PM in LOR analysis. The purpose of this paper is to develop a more practical LOR analysis approach, considering the time-dependent failure rate (TDFR) of components and the effect of PM.

Design/methodology/approach
In the proposed methodology, first, a detailed life cycle model considering the effect of various parameters related to LOR and PM is developed. A simulation-based genetic algorithm approach is then used to obtain an integrated solution for LOR and PM schedule decisions. The model is also evaluated for the various cases of quality of maintenance measured in terms of degree of restoration.

Findings
The results, from the illustrative example for a multi-indenture and multi-echelon fleet maintenance network, show that the proposed integrated strategy leads to better LCC performance compare to the conventional approach. Additionally, it is identified that the degree of restoration also affects the PM schedule as well as LOR decisions of the fleet system. Therefore, consideration of TDFR is important to truly optimize the LOR decisions. The proposed approach can be applied to fleet of any equipment.

Research limitations/implications
The approach is illustrated using a hypothetical example of an industrial system. A more complex system structure in terms of number of machines, types of machines (identical vs non-identical), number of echelons, possible repair actions at various echelons, etc. may be present for a particular industrial case. However, the approach presented is generic and can be extended to any system. Moreover, the aim of the paper is to highlight the importance of the considering PM and quality of maintenance in LOR decision making.

Originality/value
To the best of the authors’ knowledge, this is the first work which considers the effect of PM and quality of maintenance on LOR analysis. Consideration of TDFR and imperfect maintenance while optimizing LOR decisions is a complex problem. Thus, the work is of high significance from the research point of view. Also, most of the real life fleet systems use PM to extend the life of the equipment. Thus, present paper is a more practical approach for LOR analysis of such systems.
Optimal replacement policy based on the effective age of the system for a deteriorating repairable system with multiple vacations
Authors: Wu Wenfeng , Song Jianshe , Jiang Kexia , Li Hao 
Published: August 2017

PurposeThis paper aims to study the maintenance and replacement problem for a deteriorating repairable system with multiple vacations of one repairman. It proposes a new replacement policy and establishes corresponding replacement models.Design/methodology/approachIt is assumed that the repair after the system failures is not “as good as new” and the repairman is in multiple vacations. The reaching of the effective age of the system is assumed to be mutually stochastic at working state, waiting state for repair and being repaired state. Under these assumptions, a replacement policy based on the effective age of the system is applied. The long-run expected downtime per unit time and the long-run expected profit per unit time as objective functions are chosen, respectively. By using geometric process theory and renewal process theory, the mathematic models have been established and the explicit expressions of the long-run expected downtime per unit time and the long-run expected profit per unit time are derived, respectively.FindingsThe optimal replacement policy can be calculated and determined by the computer to minimize the expected downtime or maximize the expected profit. The minimum expected downtime per unit time and maximum expected profit per unit time can also be determined.Originality/valueThis replacement policy and mathematic models can be used as reference to the failure system maintenance and replacement.
A model of system limiting availability under imperfect maintenance
Authors: Alaswad Suzan , Cassady Richard , Pohl Edward , Li Xiaoping 
Published: August 2017

Purpose
The purpose of this paper is to explore the impact of the Kijima Type II imperfect repair model on the availability of repairable systems (RS). Since many individuals are interested in measuring the extent to which the system will be available after it has been run for a long time, the specific interest in this study is in the steady-state (limiting) availability behavior of such systems. Furthermore, the authors study the impact of age-based preventive maintenance (PM) on the RS performance.

Design/methodology/approach
Because of the complexity of the underlying assumptions of the Kijima Type II model, the authors use simulation modeling to estimate the system availability. Based on preliminary simulation results, the availability function achieves a steady-state value greater than zero. The system steady-state availability is then estimated from the simulation output by computing the average of the availability estimates beyond the initial transient period. Next, the authors develop a meta-model to convert the system reliability and maintainability parameters into the coefficients of the limiting availability estimate without the simulation effort. Using a circumscribed central composite experimental design, the authors confirm the accuracy of the meta-model.

Findings
The results show that the meta-model is robust, and provides good estimates of the system limiting availability. Also, the authors find that when using a Kijima Type II model for a system repair process, age-based PM can improve the steady-state availability value. Therefore, an optimal age-based PM policy that maximizes the system’s steady-state availability can be identified.

Originality/value
In practice, it is important to study the system steady-state availability because many individuals, i.e. engineers, are more interested in measuring the extent to which the system will be available after it has been run for a long time. Therefore, this study represents a significant addition to the body of knowledge related to virtual age modeling, in that it incorporates a Kijima type II model and considers system steady-state availability.
Improving information quality of Wikipedia articles with cooperative principle
Authors: Fidler Miloš , Lavbič Dejan 
Published: August 2017

Purpose
The purpose of this paper is to investigate the impact of cooperative principle on the information quality (IQ) by making objects more relevant for consumer needs, in particular case Wikipedia articles for students.

Design/methodology/approach
The authors performed a quantitative study with participants being invited to complete an online survey. Each rater evaluated three selected and re-written articles from Wikipedia by four IQ dimensions (accuracy, completeness, objectivity, and representation). Grice’s maxims and submaxims were used to re-write articles and make them more relevant for student cognitive needs. The results were analyzed with statistical methods of mean, standard deviation, Cronbach’s α, and ICC (two-way random model of single measure).

Findings
The study demonstrates that Wikipedia articles can be made more relevant for student needs by using cooperative principle with increase in IQ and also achieving higher consistency of students’ scores as recent research. In particular, students in the research perceived the abstract, constructed with cooperative principle, more objective and complete as reported in recent research.

Practical implications
The work can benefit encyclopedia editors to improve IQ of existing articles as well as consumers that would obtain more relevant information in less reading time.

Originality/value
This is one of the first attempts to empirically investigate the application of cooperate principle to make objects more relevant for consumer needs and impact of this on IQ. IQ improvement evidence is provided and impacts on IQ dimensions such as objectivity, completeness, accuracy, and representation for research community to validate and compare results.
Reciprocal nature of social capital in Facebook: an analysis of tagging activity
Authors: Ha Taehyun , Han Seunghee , Lee Sangwon , Kim Jang Hyun 
Published: August 2017

Purpose
The purpose of this paper is to investigate how we can understand social media interactions better by explicating the process of social capital formation on Facebook from a reciprocity perspective.

Design/methodology/approach
This study observed users who got tagged on Facebook by his/her friends and how s/he responded to that tagging activity. In total, 4,666 posts and 418,580 comments from The New York Times Facebook page were collected for the observation.

Findings
A majority (77.87 percent) of users who were tagged by their friends showed reactions to their tagging. In detail, 33.63, 44.20, and 0.04 percent of users responded by comments, “Likes”, and “Shares”, respectively. In total, 90.11 percent of the comments and 98.58 percent of the “Likes” were expressed on a comment or sub-comment, and only 9.89 percent of the comments and 1.42 percent of the “Likes” were expressed on a post. This indicates that a high percentage of users respond to their tagging notification, and they prefer dialogic responses to non-dialogic responses.

Originality/value
Previous studies have focused on photo tagging activity in social media, but user tagging activity had not been studied enough. This study examines the effects of Facebook tagging activity from a reciprocal perspective.
Providing consumers with a representative subset from online reviews
Authors: Zhang Jin , Ren Ming , Xiao Xian , Zhang Jilong 
Published: August 2017

PurposeThe purpose of this paper is to find a representative subset from large-scale online reviews for consumers. The subset is significantly small in size, but covers the majority amount of information in the original reviews and contains little redundant information.Design/methodology/approachA heuristic approach named RewSel is proposed to successively select representatives until the number of representatives meets the requirement. To reveal the advantages of the approach, extensive data experiments and a user study are conducted on real data.FindingsThe proposed approach has the advantage over the benchmarks in terms of coverage and redundancy. People show preference to the representative subsets provided by RewSel. The proposed approach also has good scalability, and is more adaptive to big data applications.Research limitations/implicationsThe paper contributes to the literature of review selection, by proposing a heuristic approach which achieves both high coverage and low redundancy. This study can be applied as the basis for conducting further analysis of large-scale online reviews.Practical implicationsThe proposed approach offers a novel way to select a representative subset of online reviews to facilitate consumer decision making. It can also enhance the existing information retrieval system to provide representative information to users rather than a large amount of results.Originality/valueThe proposed approach finds the representative subset by adopting the concept of relative entropy and sentiment analysis methods. Compared with state-of-the-art approaches, it offers a more effective and efficient way for users to handle a large amount of online information.
Two benefits firms derive from unionized workforces
Authors: Abraham Steven Eric 
Published: August 2017

PurposeThe purposes of this paper are to discuss why firms are resistant to unionization of their employees and to discuss the potential benefits firms derive if their employees are unionized. There are benefits to firms if their employees are unionized, however, and firms whose workforces are unionized should take advantage of these benefits.Design/methodology/approachAnalysis and discussion of the drawbacks and benefits of unionization to firms.FindingsFirms benefit in two ways if their workforces are unionized. First, unionization reduces employee turnover. Second, employee involvement programs are generally more effective in unionized firms, while they are often held to be illegal in nonunion firms. Therefore, managers in unionized firms should work with the unions representing their employees to further reduce turnover and make Employee Involvement programs even more effective.Originality/valueAs employees sometimes opt to unionize despite firms’ wishes to the contrary, this paper discusses the benefits of unionized workforces and advocates that management in unionized firms develop positive relations with unions to derive these benefits.
Naphthalene biodegradation under oxygen‐limiting conditions: community dynamics and the relevance of biofilm‐forming capacity
Authors: Martirani‐Von Abercron Sophie‐Marie , Marín Patricia , Solsona‐Ferraz Marta , Castañeda‐Cataña Mayra‐Alejandra , Marqués Silvia 
Published: August 2017

SummaryToxic polycyclic aromatic hydrocarbons (PAHs) are frequently released into the environment from anthropogenic sources. PAH remediation strategies focus on biological processes mediated by bacteria. The availability of oxygen in polluted environments is often limited or absent, and only bacteria able to thrive in these conditions can be considered for bioremediation strategies. To identify bacterial strains able to degrade PAHs under oxygen‐limiting conditions, we set up enrichment cultures from samples of an oil‐polluted aquifer, using either anoxic or microaerophilic condition and with PAHs as the sole carbon source. Despite the presence of a significant community of nitrate‐reducing bacteria, the initial community, which was dominated by Betaproteobacteria, was incapable of PAH degradation under strict anoxic conditions, although a clear shift in the structure of the community towards an increase in the Alphaproteobacteria (Sphingomonadaceae), Actinobacteria and an uncultured group of Acidobacteria was observed in the enrichments. In contrast, growth under microaerophilic conditions with naphthalene as the carbon source evidenced the development of a biofilm structure around the naphthalene crystal. The enrichment process selected two co‐dominant groups which finally reached 97% of the bacterial communities: Variovorax spp. (54%, Betaproteobacteria) and Starkeya spp. (43%, Xanthobacteraceae). The two dominant populations were able to grow with naphthalene, although only Starkeya was able to reproduce the biofilm structure around the naphthalene crystal. The pathway for naphthalene degradation was identified, which included as essential steps dioxygenases with high affinity for oxygen, showing 99% identity with Xanthobacter polyaromaticivorans dbd cluster for PAH degradation. Our results suggest that the biofilm formation capacity of Starkeya provided a structure to allocate its cells at an appropriate distance from the toxic carbon source.
Influence of luteinizing hormone support on granulosa cells transcriptome in cattle
Authors: Nivet Anne‐Laure , Vigneault Christian , Blondin Patrick , Sirard Marc‐Andre 
Published: August 2017

AbstractIn cows, the use of follicle‐stimulating hormone (FSH) to stimulate follicular growth followed by a short period of FSH withdrawal has been shown to be beneficial for oocyte developmental competence. Although this treatment represents a useful optimization to generate highly competent oocytes, the underlying physiological process is not completely understood. The goal of this study was to investigate the role of luteinizing hormone (LH) action during FSH withdrawal before ovulation. To accomplish this, LH release was pharmacologically inhibited during the coasting period with gonadotropin‐releasing hormone (GnRH) antagonists. Granulosa cells samples were obtained from cows stimulated with FSH during 3 days followed by a coasting period of 68 h and treated with a GnRH antagonist (cetrorelix group) or not (control). A significant reduction in the number of follicles at >10 mm diameter was observed with the cetrorelix group and gene expression of granulosa cells reveals that 747 transcripts are potentially regulated by LH. Further analysis indicates how the absence of LH may trigger early atresia, the upregulation of atretic agent as tumor protein P53 and transforming growth factor β1 and the inhibition of growth support. This work allows identification of genes that are associated with maintained follicular growth and conversely the ones leading to atresia in dominant pre‐ovulatory follicles.