bluuebunny/crossref_metadata_2025_split huggingface dataset:
Towards objective measurement of reproductive performance of traditionally managed goat flocks in the drylands of Ethiopia
Authors: Alemayehu Gezahegn , Mamo Gezahegne , Alemu Biruk , Desta Hiwot , Wieland Barbara 
Published: February 2021

AbstractReproductive performance is a key determinant for the efficiency of goat production. Regular monitoring of reproductive efficiency is essential to assess management and to avoid financial losses due to poor performance. To allow more objective measurement and comparisons over time, we propose a novel quantitative approach for defining annual reproductive performance by combining common performance indicators into a goat flock index. Commonly used reproductive performance measures were collected from 242 goat flocks in four districts in dryland of Ethiopia between July 2018 and February 2019. Principal component analysis (PCA) was performed to identify biologically meaningful latent components that explain annual reproductive output (ARO) and annual reproductive wastage (ARW). Together with the remaining annual reproductive performance measures, the ARO and ARW components were included in a PCA to derive an algorithm for a goat annual reproductive performance index (G-ARPI). One component representing variation in kidding interval, PCARO1 and PCARW1 was extracted and normalized to a 10-scale value. The flocks were classified into good performing (15.63%) with index > 8.5, moderately performing (48.21%) with index values ranging from 6.5 to 8.5 and poor performing (36.16%) with index < 6.5. Good performing flocks have higher scores for reproductive output measures, lower scores for reproductive wastage and lower kidding interval. The proposed G-ARPI can be used as an objective tool to compare reproductive performance between management systems, evaluate the costs of poor reproductive management and will be useful for economic models that aim to identify the most cost-efficient intervention option and monitor the impact of interventions. We present here the index for goat production in dryland systems in Ethiopia; the approach can easily be adapted to other production systems elsewhere.
Science education against the rise of fascist and authoritarian movements: towards the development of a pedagogy for democracy
Authors: Galamba Arthur , Matthews Brian 
Published: February 2021

AbstractIn the twenty-first century, the rise and support of fascism-related views threaten freedom of speech, freedom of sexual orientation, religious tolerance and progressive agendas that advocate equity. We argue that mainstream science education generally does not, but should, educate students against fascism-related views—such as racism, sexism, homophobia and religious intolerance—with a view to strengthening mutual respect and the common good. We argue some science teaching practices are found to be suitable to fascism-like ideologies (e.g. race in genetics teaching), and that the use of the concept of ‘scientific literacy’ has focused on neoliberal possessive individualism. As a consequence, mainstream science education overlooks the development of sympathy, altruism and interpersonal skills. We also discuss the activity of science education in authoritarian, undemocratic regimes in history, showing that fascist regimes have long used ‘apolitical’ scientists’ achievements to establish and expand regimes’ intolerant and violent ideologies. We use that historical relationship to argue fascism is science education’s business. Given the fear that current political discourses in many countries are again swinging towards fascism, we outline potential pathways for science education which focus on the social and emotional development of students. We argue that to develop a pedagogy for democracy, that attends to equity and social justice, it is imperative it enables pupils to develop at a psychological level with diverse others, including through their own agency. This pedagogy builds on critical pedagogies.
Pyrvinium pamoate inhibits cell proliferation through ROS-mediated AKT-dependent signaling pathway in colorectal cancer
Authors: Zheng Wenqian , Hu Jinhui , Lv Yiming , Bai Bingjun , Shan Lina , Chen Kangke , Dai Sheng , Zhu Hongbo 
Published: February 2021

AbstractThe use of the anthelmintic drug pyrvinium pamoate (PP) in cancer therapy has been extensively investigated in the last decade. PP has been shown to have an inhibitory effect in colorectal cancer (CRC), but the underlying mechanism remains elusive. We aimed to investigate the antitumor activity and mechanisms of PP in CRC. In the present study, we used CCK-8 assays, colony formation assays, and western blotting to reveal that PP effectively suppressed CRC cell proliferation and the AKT-dependent signaling pathway in a concentration-dependent and time-dependent manner. Flow cytometric analysis and fluorescence microscopy demonstrated that PP increased intracellular reactive oxygen species (ROS) accumulation. We found that the inhibitory effect of PP on cell proliferation and AKT protein expression induced by PP could be partially reversed by N-acetyl-l-cysteine (NAC), an ROS scavenger. In addition, the results also demonstrated that PP inhibited cell migration by modulating epithelial-to-mesenchymal transition (EMT)-related proteins, including E-cadherin and vimentin. In conclusion, our data suggested that PP effectively inhibited cell proliferation through the ROS-mediated AKT-dependent signaling pathway in CRC, further providing evidence for the use of PP as an antitumor agent.
Sigma-Lognormal Modeling of Speech
Authors: Carmona-Duarte C. , Ferrer M. A. , Plamondon R. , Gómez-Rodellar A. , Gómez-Vilda P. 
Published: February 2021

AbstractHuman movement studies and analyses have been fundamental in many scientific domains, ranging from neuroscience to education, pattern recognition to robotics, health care to sports, and beyond. Previous speech motor models were proposed to understand how speech movement is produced and how the resulting speech varies when some parameters are changed. However, the inverse approach, in which the muscular response parameters and the subject’s age are derived from real continuous speech, is not possible with such models. Instead, in the handwriting field, the kinematic theory of rapid human movements and its associated Sigma-lognormal model have been applied successfully to obtain the muscular response parameters. This work presents a speech kinematics-based model that can be used to study, analyze, and reconstruct complex speech kinematics in a simplified manner. A method based on the kinematic theory of rapid human movements and its associated Sigma-lognormal model are applied to describe and to parameterize the asymptotic impulse response of the neuromuscular networks involved in speech as a response to a neuromotor command. The method used to carry out transformations from formants to a movement observation is also presented. Experiments carried out with the (English) VTR-TIMIT database and the (German) Saarbrucken Voice Database, including people of different ages, with and without laryngeal pathologies, corroborate the link between the extracted parameters and aging, on the one hand, and the proportion between the first and second formants required in applying the kinematic theory of rapid human movements, on the other. The results should drive innovative developments in the modeling and understanding of speech kinematics.
Evidence for divergence of DNA methylation maintenance and a conserved inhibitory mechanism from DNA demethylation in chickens and mammals
Authors: Tada Masako , Hayashi Ayaka , Asano Yumi , Kubiura-Ichimaru Musashi , Ito Takamasa , Yoshii Miho , Kimura Hiroshi , Matsuda Yoichi , Oshimura Mitsuo 
Published: February 2021

Abstract
Background
DNA methylation is a significant epigenetic modification that is evolutionarily conserved in various species and often serves as a repressive mark for transcription. DNA methylation levels and patterns are regulated by a balance of opposing enzyme functions, DNA methyltransferases, DNMT1/3A/3B and methylcytosine dioxygenases, TET1/2/3. In mice, the TET enzyme converts DNA cytosine methylation (5mC) to 5-hydroxymethylcytosine (5hmC) at the beginning of fertilisation and gastrulation and initiates a global loss of 5mC, while the 5mC level is increased on the onset of cell differentiation during early embryonic development.

Objective
Global loss and gain of DNA methylation may be differently regulated in diverged species.

Methods
Chicken B-cell lymphoma DT40 cells were used as an avian model to compare differences in the overall regulation of DNA modification with mammals.

Results
We found that DNA methylation is maintained at high levels in DT40 cells through compact chromatin formation, which inhibits TET-mediated demethylation. Human and mouse chromosomes introduced into DT40 cells by cell fusion lost the majority of 5mC, except for human subtelomeric repeats.

Conclusion
Our attempt to elucidate the differences in the epigenetic regulatory mechanisms between birds and mammals explored the evidence that they share a common chromatin-based regulation of TET–DNA access, while chicken DNMT1 is involved in different target sequence recognition systems, suggesting that factors inducing DNMT–DNA association have already diverged.
Loads analysis and structural optimization of a high aspect ratio, composite wing aircraft
Authors: Sinha Kautuk , Klimmek Thomas , Schulze Matthias , Handojo Vega 
Published: February 2021

AbstractComposite structures have shown a prominent impact in the aircraft structural design. With an increasing shift towards incorporating more composite materials in the primary aircraft structure it is imperative to have corresponding design tools to simplify the design process. In the present work, a simplified implementation for composite optimization has been developed within the DLR-AE (German Aerospace Centre, Institute of Aeroelasticity) automated aeroelastic structural design framework cpacs-MONA. This paper presents the results of structural optimization of a high aspect ratio composite wing aircraft model developed in the DLR project ATLAs. The generation of almost all involved simulation models for this study is done using the in-house DLR tool ModGen. An aeroelastic trim analysis is conducted for various manoeuvre and gust conditions. A load selection process is used to determine the most relevant sizing load cases. A comparison is made between the optimization results of a composite wing and an aluminium wing to demonstrate the more favourable strength to weight ratio of the composite wing. A manoeuvre load alleviation procedure has been introduced in the load calculation process. The results show further weight savings in the design process when load alleviation is utilized due to reduction in the span wise bending moment.
Multi-stage timetable rescheduling for high-speed railways: a dynamic programming approach with adaptive state generation
Authors: Feng Guoqi , Xu Peng , Cui Dongliang , Dai Xuewu , Liu Hui , Zhang Qi 
Published: February 2021

AbstractA dynamic programming (DP) approach with adaptive state generation and conflicts resolution is developed to address the timetable-rescheduling problem (TRP) at relatively lower computation costs. A multi-stage decision-making model is first developed to represent the timetable-rescheduling procedure in high-speed railways. Then, an adaptive state generation method by reordering the trains at each station is proposed to dynamically create the possible states according to the states of previous stages, such that the infeasible states can be removed and the search space is reduced. Then, conflicts are resolved by retiming the arrival and/or departure times of trains. Furthermore, the state transfer equation is built and Bellman equation is developed to derive the solution to minimize the total delay time (TT). A series of simulation experiments and a real-world case study are used to evaluate the performance of the proposed method. The simulation experiments indicate that the proposed method is able to find the optimal timetable with appropriate overtaking at right stations and reduce the total delay by 62.7% and 41.5% with respect to the First-Come-First-Serve (FCFS) and First-Schedule-First-Serve (FSFS) strategy that are widely used in practice. Comparing to the intelligent scheduling method (e.g., Ant Colony Optimization and Particle Swarm Optimization), similar objective performance can be achieved at a much lower cost of computation time, which make the proposed method more applicable to the TRP in daily operation of high-speed railway.
Improved bag-of-features using grey relational analysis for classification of histology images
Authors: Pal Raju , Saraswat Mukesh , Mittal Himanshu 
Published: February 2021

AbstractAn efficient classification method to categorize histopathological images is a challenging research problem. In this paper, an improved bag-of-features approach is presented as an efficient image classification method. In bag-of-features, a large number of keypoints are extracted from histopathological images that increases the computational cost of the codebook construction step. Therefore, to select the a relevant subset of keypoints, a new keypoints selection method is introduced in the bag-of-features method. To validate the performance of the proposed method, an extensive experimental analysis is conducted on two standard histopathological image datasets, namely ADL and Blue histology datasets. The proposed keypoint selection method reduces the extracted high dimensional features by 95% and 68% from the ADL and Blue histology datasets respectively with less computational time. Moreover, the enhanced bag-of-features method increases classification accuracy by from other considered classification methods.
A bi-stage surrogate-assisted hybrid algorithm for expensive optimization problems
Authors: Ren Zhihai , Sun Chaoli , Tan Ying , Zhang Guochen , Qin Shufen 
Published: February 2021

AbstractSurrogate-assisted meta-heuristic algorithms have shown good performance to solve the computationally expensive problems within a limited computational resource. Compared to the method that only one surrogate model is utilized, the surrogate ensembles have shown more efficiency to get a good optimal solution. In this paper, we propose a bi-stage surrogate-assisted hybrid algorithm to solve the expensive optimization problems. The framework of the proposed method is composed of two stages. In the first stage, a number of global searches will be conducted in sequence to explore different sub-spaces of the decision space, and the solution with the maximum uncertainty in the final generation of each global search will be evaluated using the exact expensive problems to improve the accuracy of the approximation on corresponding sub-space. In the second stage, the local search is added to exploit the sub-space, where the best position found so far locates, to find a better solution for real expensive evaluation. Furthermore, the local and global searches in the second stage take turns to be conducted to balance the trade-off of the exploration and exploitation. Two different meta-heuristic algorithms are, respectively, utilized for the global and local search. To evaluate the performance of our proposed method, we conduct the experiments on seven benchmark problems, the Lennard–Jones potential problem and a constrained test problem, respectively, and compare with five state-of-the-art methods proposed for solving expensive problems. The experimental results show that our proposed method can obtain better results, especially on high-dimensional problems.
Coal petrology analysis and implications in depositional environments from upper Cretaceous to Miocene: a study case in the Eastern Cordillera of Colombia
Authors: Guatame Clara , Rincón Marco 
Published: February 2021

AbstractThe Piedemonte Llanero Basin is located on the eastern side of the Eastern Cordillera of the Colombian Andes. It has been the subject of numerous geological studies carried out for the oil sector, mainly. This study presents the coal-petrographical features of 15 coal seams of four geological formations from Late Cretaceous to Middle Miocene (Chipaque formation, Palmichal group, Arcillas del Limbo formation, and San Fernando formation). Analysis of 33 samples indicates enrichment in vitrinite, while liptinite and inertinite concentrations vary according to the stratigraphic position. Reflectance indicates that the coal range gradually decreases from highly volatile bituminous C (Chipaque formation) to subbituminous C (San Fernando formation). The microlithotypes with the highest concentrations are clarite and vitrinertoliptite. Maceral composition and coal facies indicate changes in the depositional conditions of the sequence. The precursor peat from Late Cretaceous to Late Paleocene accumulated under limnic conditions followed by telmatic in Late Eocene–Early Miocene. The coal facies indices show wet conditions in forest swamps with variations in the flooding surface, influxes of brackish water and good tissue preservation. The tectonic conditions along the Piedemonte Llanero basin is evident, from post-rift to foreland basin, evidenced by oxic and anoxic periods reflected in the maceral composition and its morphology. The coal environment corresponds to an estuarine system started in the Chipaque formation evolving to the lacustrine conditions in the San Fernando formation.
Influence of coal properties on coal conversion processes-coal carbonization, carbon fiber production, gasification and liquefaction technologies: a review
Authors: Keboletse K. P. , Ntuli F. , Oladijo O. P. 
Published: February 2021

AbstractCoal due to its relatively large quantities and wide distribution worldwide has generated renewed interest in research and development with the aim of establishing coal conversion technologies that are technically reliable, environmentally and economically feasible. It has proved to be a prominent energy source in emerging markets with increasing energy demand by accounting for the largest increase in the demand of energy amongst all other energy sources. Furthermore, with its higher mesophase content, coal tar is an appropriate raw material for precursors in the production of carbon fiber. However, whenever a material is put to use, it is important to be able to associate its properties to the behavioral characteristics during a conversion process so as to have a basis for opting for the material in a given process or adjusting the operating conditions in order to optimize the material utilization. Therefore, as with any other material, it is important to be able to relate the properties of coal to its utilization. A review was carried out on the influence of coal properties on four main utilization technologies: gasification, carbonization, liquefaction and carbon fibre production. Among several properties rank, type, mineral matter content, distribution of trace elements, structural composition and pore structure were found to be most influential on the behavior of coal during conversion processes.
Firm strategies and distributional dynamics: labour share in Italian medium-large firms
Authors: Bloise Francesco , Brunetti Irene , Cirillo Valeria 
Published: February 2021

AbstractUsing an original database on medium and large Italian firms built by merging theRilevazione Imprese e Lavororun by INAPP in 2010 and 2015 with the AIDA archive by Bureau Van Dijk, we show that the trend of the labour share differs along the labour share distribution. We carry out Unconditional Quantile Regression decompositions to explore the main drivers behind this heterogeneity. Thus, we contribute to the literature on the dynamics of the labour share since we investigate phenomena which cannot be observed through a macro perspective or by looking at a single parameter of the labour share distribution. After including in our specifications several firm-level characteristics and considering composition effects, we find that outsourcing is the main factor which plays a role in reducing the labour share along the distribution. Further different mechanisms act in the various parts of the distribution: unionization contributes to increase the labour share at the top of the labour share distribution, while the introduction of some forms of product (process) innovations is associated with a negative (positive) change in the labour share for those firms at the bottom of the labour share distribution.
Does Taking a Short Break from Social Media Have a Positive Effect on Well-being? Evidence from Three Preregistered Field Experiments
Authors: Przybylski Andrew K. , Nguyen Thuy-vy T. , Law Wilbert , Weinstein Netta 
Published: February 2021

AbstractConcerns about the consequences of social media use on well-being has led to the practice of taking a brief hiatus from social media platforms, a practice known as “digital detoxing.” These brief “digital detoxes” are becoming increasingly popular in the hope that the newly found time, previously spent on social media, would be used for other, theoretically more rewarding, activities. In this paper, we test this proposition. Participants in three preregistered field experiments (ntot = 600) were randomly assigned to receiving each of two conditions on each of two different days: a normal-use day or an abstinence day. Outcomes (social relatedness, positive and negative affect, day satisfaction) were measured on each of the two evenings of the study. Results did not show that abstaining from social media has positive effects on daily well-being (in terms of social relatedness, positive and negative affect, day satisfaction) as suggested by the extant literature. Participants reported similar well-being on days when they used social media and days when they did not. Evidence indicated that abstinence from social media had no measurable positive effect on well-being, and some models showed significant deficits in social relatedness and satisfaction with one’s day. We discuss implications of the study of social media hiatus and the value of programmatic research grounded in preregistered experimental designs.
Distinguishing Perceived Hope and Dispositional Optimism: Theoretical Foundations and Empirical Findings beyond Future Expectancies and Cognition
Authors: Krafft Andreas M. , Guse Tharina , Maree David 
Published: February 2021

AbstractAt first glance, hope and optimism appear to be two almost identical concepts. The predominant cognitive theories maintain that both are based on positive future expectancies regarding goal attainment. However, other approaches recommend distinguishing between hope and future expectancies and sustain that the differences between hope and optimism are of a more substantial nature. The present study investigates the distinction between a new short instrument to measure hope as perceived by the general public, and dispositional optimism as measured by the revised Life Orientation Test (LOT-R) in a South African sample. After comparing both instruments using confirmatory factor analysis and exploratory structural equation modelling in Mplus, a number of encouraging results emanated from the data. First, the Perceived Hope Scale (PHS) is a unitary and coherent measure of perceived hope. Second, perceived hope, as measured by the PHS, and optimism and pessimism as measured by the LOT-R, are psychometrically distinguished latent dimensions, optimally specified by their indicator variables. Furthermore, perceived hope represents a fundamental construct in the prediction of health outcomes and well-being and is an important antecedent to optimism and dispositional hope. Perceived hope is thus an important additional facet to consider in investigating well-being.