bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sovereign credit ratings and bond yield spreads in emerging markets
Authors: Thazhugal Govindan Nair Saji 
Published: December 2019

Purpose
This paper, using the model suggested by Cantor and Pecker (1996), aims to explore the relations between sovereign ratings and bond yield spreads in emerging markets.

Design/methodology/approach
The ordinary least square regression procedure administered on the most recent sovereign ratings of 46 countries demonstrates how the macroeconomic information embody in the sovereign rating scores predict their bond yield spreads relative to the yield on US Treasury bond.

Findings
The research finds that the assigned rating scores do not herald the complete elites of the macroeconomic conditions in emerging markets, and there is more incremental information in the publicly available macroeconomic variables, which is much useful in predicting bond yield spreads than that embedded into the sovereign ratings.

Practical implications
The outcomes of the research have strategic implications for global investors and policymakers. The use of credit rating scores along with the macroeconomic fundamentals in emerging economies produces better predictions than the benchmark predictions solely based on the rating scores suggested by the previous research.

Originality/value
This study is the first one to address the issues related to sovereign ratings and bond yield spread in developing and emerging markets using the most recent ratings during the period of the economic recoveries, following the global financial crisis of 2008.
Trend analysis of online travel review text mining over time
Authors: Zhang Kaile , Koshijima Ichiro 
Published: December 2019

PurposeThe reviews of online tourism have not been taken advantage of effectively because the text data of such reviews is enormous and its current, in-depth research is still in infancy. Therefore, it is expected that the text data could be processed by the method of text mining to better understand the implicit information. The purpose of this paper is to contribute to tourism practitioners and tourists to conveniently use the texts through appropriate visualization processing techniques. In particular, time-changing reviews can be used to reflect the changes in tourists’ feedback and concerns.Design/methodology/approachLatent semantic analysis is a new branch of semantics. Every term in the document can be regarded as a single point in multi-dimensional space. When a document with semantics comes into such space, the distribution of the document is not random, but will obey some type of semantic structure.FindingsFirst, overall grasping for the big data is applicable. Second, propose a direct method is proposed that allows more non-language processing researchers or proprietors to use the data. Lastly, the results of changes in different spans of times are investigated.Originality/valueThis paper proposes an approach to disclose a significant number of travel comments from different years that may generate new ideas for tourism. The authors put forward a processing approach to deal with large amounts of texts of comments. Using the case study of Mt. Lushan, the various changes of travel reviews over the years are successfully visualized and displayed.
Effect of spalling on predicted temperature gradients and flexural capacity: numerical model
Authors: Lakhani Hitesh , Hofmann Jan 
Published: December 2019

Purpose
The paper aims to present an advanced 2 D transient heat transfer analysis capable of accounting for the effect of spalling in terms of amount, location and time. The model accounts for moving thermal boundary conditions to comply with the changing member cross section. The discussed numerical model provides a tool to quantify the effect of spalling on the flexural capacity of reinforced concrete beams.

Design/methodology/approach
The implementation of the presented numerical model in an in-house code and its validation has been discussed. The thermal subroutine has been sequentially coupled with the mechanical subroutine (sectional-analysis) to compute the variation of sectional moment carrying capacity with exposure time.

Findings
The temperatures predicted while considering spalling were in good agreement with experiments available in literature. The presented results also emphasise the importance of considering the time of spalling. The results also show that the fire rating of simply supported beams is also affected by spalling in the compression zone.

Research limitations/implications
It should be acknowledged that the model does not predict spalling, rather is developed as a tool to study the effect of spalling. The model takes the information related to spalling in terms of the location, amount and time, as user input.

Originality/value
The paper quantitatively presents the effect of spalling on the predicted temperature variation across the beam cross section and the moment carrying capacity.
Second generation involvement and corporate innovation: evidence from China
Authors: Huang Haijie , Lyu Changjiang , Zhu Xiaowen 
Published: December 2019

Purpose
The purpose of this paper is to study the effect of second generation involvement on corporate innovation in Chinese family firms.

Design/methodology/approach
Based on the manually collected sample of listed Chinese family firms from 2003 to 2014, the study empirically examines the impact of second generation involvement on corporate innovation. The authors apply a difference-in-differences research design and a Heckman two-stage least squares regression to relieve the endogeneity concerns.

Findings
The research finds a positive relationship between second generation involvement and corporate innovation. This effect is more pronounced among the firms appointing second generation family members with overseas training experience and firms with weak external monitoring. Further analysis shows that the curtailment of related party transactions and the improvement of accounting information quality are important channels.

Practical implications
The findings provide several practical implications for Chinese family firms to survive the succession process and maintain competitive advantages across generations.

Originality/value
First, this study is helpful to understand the strategies adopted by family firms to maintain their long-term competitiveness and pursue continuing growth across generations. Second, the findings are also consistent with the transfer cost hypothesis of Fan et al. (2012) and Bennedsen et al. (2015). Finally, the findings imply that second generation involvement has a substitutive effect for external monitoring mechanisms.
Flame-retardancy, thermal and coating properties of P-containing poly-acrylate resin cured with MF resin
Authors: Liang Xinyue , Qiao Hui , Xu Guilong , Zhang Yanchong , Liang Yun , Hu Jian 
Published: December 2019

Purpose
The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. Many studies, including the authors’ previous study, have proved that covalent-incorporated phosphorous-containing (P-containing) monomer onto the PA resin can exhibit better flame resistance than that by an additive approach. However, other properties such as thermal stability, coating properties are still deteriorated. To further improve the flame-retardancy and other comprehensive properties of the P-containing PA resin, in this study, melamine formaldehyde(MF) resin was used not only as a curing agent to enhance the coating properties of the PA resin, but also as a nitrogen-containing (N-containing) resin to form a P-N synergistic effect and therefore further improve its flame retardancy.

Design/methodology/approach
Epoxy resin phosphorous acid-modified (EPPA-modified) PA (EPPA-PA) resin was first prepared and then using MF resin as curing agent. The flame retardancy of the cured resin was tested by the limiting oxygen index (LOI) and UL 94 methods. The thermal stability of the cured resin was studied by TGA. The coating technology such as adhesion property, pencil hardness and anti-solvent properties were characterized according to methods of International Standards ISO2409-1992, ISO 15184-1998 and ISO-15184-2012, respectively. The micro-char morphology of the char residue was observed by SEM.

Findings
The results showed that by using MF resin as curing agent has provided the PA resin with excellent coating properties and thermal stability, but also gave a P-N synergistic effect which has greatly enhanced the flame retardancy of the cured resin. The cured resin system containing only 1.7 Wt.% P content and 5.3 Wt.% N content can reach a LOI of 26.9 per cent and pass the V-0 rating in the UL-94 test.

Research limitations/implications
This resin system releases formaldehyde due to the MF resin.

Practical implications
It is expected that the large-scale production of this EPPA-PA resin cured by MF resin system will enable practical industrial applications.

Originality/value
This method for the synthesis of a P- and N-containing PA resin system is newfangled.
The effect of CSR commitment on firms’ level of internationalization
Authors: Khojastehpour Morteza , Saleh Md Abu 
Published: December 2019

PurposeCorporate social responsibility (CSR) has received considerable research attention globally over the past decade. Although a growing number of prior studies have investigated the various dimensions of CSR in general terms, few studies have investigated the critical role that CSR can play in the internationalization process of firms.Design/methodology/approachUsing S&P 500 companies during 2004-2014, the authors found that the level of CSR commitment raises the level of reliability of firm and allows further international penetration. Moreover, better regulatory quality of host country is at actual support of internationalization only when considering the short term.FindingsBetter regulatory quality of host country is at actual support of internationalization only when considering the short term.Originality/valueThe authors build on internationalization theory and CSR and examine the relationship between firms’ level of internationalization and CSR commitment.
The role of biotic interactions in determining metal hyperaccumulation in plants
Authors: Mohiley Anubhav , Tielbörger Katja , Seifan Merav , Gruntman Michal 
Published: December 2019

Abstract

Heavy metal hyperaccumulation (MH) is a rare trait found in plant species that inhabit metal‐contaminated soils. Two main hypotheses proposed to explain the selective advantage of MH are the elemental defence hypothesis and elemental allelopathy hypothesis. The elemental defence hypothesis suggests that MH functions as defence against herbivores while the elemental allelopathy hypothesis suggests that MH acts to inhibit the growth of neighbours. Nevertheless, these hypotheses are not likely to be mutually exclusive. Here, we present the first study to test both hypotheses simultaneously. We examined these hypotheses with the Cd hyperaccumulator, Arabidopsis halleri, which inhabits both metalliferous and non‐metalliferous soils, thus providing an opportunity to test the hypotheses of both habitats.

Arabidopsis halleri plants originating from several populations in both metalliferous and non‐metalliferous soils were grown in a greenhouse in soils with or without cadmium (Cd). Their leaves were used in a feeding experiment with a specialist herbivore and in a set of leaf‐leachate experiments that tested their effect on seed germination and seedling establishment of species co‐occurring with A. halleri. Finally, a field survey in several A. halleri populations was conducted to compare herbivore load between A. halleri and neighbours from metalliferous versus non‐metalliferous soils.

Results of the feeding experiment and field survey suggest that Cd accumulation in A. halleri leaves could provide it with defence against herbivores. Results of the leaf‐leachate experiments reveal that Cd accumulation has no effect on seed germination of neighbouring species but inhibits seedling establishment, particularly of plant species originating from non‐metalliferous soils.

Our results suggest that both herbivores and competing neighbours may jointly select for MH in plants. Moreover, MH could provide a selective advantage particularly in non‐metalliferous soils, where neighbouring plants lack metal tolerance. These results highlight the importance of including different origins and populations of both the target species and its neighbouring plant species when studying the ecological role of MH.

A free Plain Language Summary can be found within the Supporting Information of this article.
Conserving the holobiont
Authors: Carthey Alexandra J. R. , Blumstein Daniel T. , Gallagher Rachael V. , Tetu Sasha G. , Gillings Michael R. 
Published: December 2019

Abstract

Organismal biology has undergone a dramatic paradigm shift in the last decade. The realization that host cells and genes are outnumbered by symbiotic microbial cells and their genes has forced us to rethink our focus on ‘individuals’. It is also becoming increasingly clear that the ecology and biology of animals and plants are intimately connected with their microbial partners. In the context of conserving functioning species, such revelatory insights beg the question—what exactly should we be trying to conserve?

Here, we review how an understanding of host–microbe interactions can benefit conservation biology. We propose a way forward for conservation biologists, to gather evidence of the potential effects of changes to plant and animal microbiomes, and to incorporate the holobiont concept into applied conservation practice.

In humans, microbes influence physiology, health, behaviour and psychology. In animals and plants, microbes similarly influence critically important components of health, communication and (in animals) behaviour. Together, the animal or plant and all of its associated micro‐organisms are termed the holobiont.

At the same time, humans are now the strongest evolutionary force on the planet, causing global change at unprecedented scale. We know that microbial diversity in humans has been compromised in urban societies, with a growing list of consequences for health and function. While we still have limited evidence for similar effects in plants and animals, anthropogenic factors that affect diversity are also likely to affect animal and plant microbiomes, with similar associated effects on host function and health.

Microbiome research is still in its relative infancy, particularly in its application to plants and animals, yet the tools are becoming more widely available and affordable. Forward‐looking conservation biologists could harness such tools and apply them to the study of plant and animal microbiomes with the goal of understanding which microbiota might be required to ensure future viability of conserved host populations.

For now, the precautionary principle applies. We suggest that, to meaningfully and effectively conserve a species, we must also consider how to conserve the bacteria, viruses, fungi and other symbionts intimately associated with that macro‐organism.

A free Plain Language Summary can be found within the Supporting Information of this article.
High‐resolution unmanned aerial vehicle aeromagnetic surveys for mineral exploration targets
Authors: Walter C. , Braun A. , Fotopoulos G. 
Published: December 2019

ABSTRACTRecent advancements in geophysical exploration have been realized through reliably integrating unmanned aerial vehicle platforms with lightweight, high‐resolution magnetometer payloads. Unmanned aerial vehicle aeromagnetic surveys can provide a contemporary data product between the two end‐members of coverage and resolution attained using manned airborne and terrestrial magnetic surveys. This new data product is achievable because unmanned aerial vehicle platforms can safely traverse with magnetometer payloads at flight elevations closer to ground targets than manned airborne surveys, while also delivering an increased coverage rate compared to walking conventional terrestrial surveys. This is a promising new development for geophysical and mineral exploration applications, especially in variable terrains. A three‐dimensional unmanned aerial vehicle aeromagnetic survey was conducted within the Shebandowan Greenstone Belt, northwest of Thunder Bay, Ontario, Canada, in July 2017. A series of two‐dimensional grids (∼500 m × 700 m) were flown at approximate elevations of 35, 45 and 70 m above ground level using a Dà‐Jiāng Innovations multi‐rotor unmanned aerial vehicle (S900) and a GEM Systems, Inc., Potassium Vapour Magnetometer (GSMP‐35U). In total, over 48 line‐km of unmanned aerial vehicle aeromagnetic data were flown with a line spacing of 25 m. The collected aeromagnetic data were compared to a regional heliborne aeromagnetic survey flown at an elevation of approximately 85 m above the terrain, with a line spacing of 100 m, as well as a follow‐up terrestrial magnetic survey. The first vertical derivative of the gathered unmanned aerial vehicle total magnetic field data was calculated both directly between each of the different flight elevations, and indirectly by calculating the values predicted using upward continuation. This case study demonstrates that low flight elevation unmanned aerial vehicle aeromagnetic surveys can reliably collect industry standard total magnetic field measurements at an increased resolution when compared to manned airborne magnetic surveys. The enhanced interpretation potential provided by this approach also aided in delineating structural controls and hydrothermal fluid migration pathways (a pair of adjacent shear zones) related to gold mineralization on site. These structural features were not clearly resolved in the regional manned airborne magnetic data alone, further demonstrating the utility of applying high‐resolution unmanned aerial vehicle aeromagnetic surveys to mineral exploration applications. The conclusions and interpretations drawn from the unmanned aerial vehicle aeromagnetic data, coupled with historical data, were applied to make a new gold mineralization discovery on the site, assayed at 15.7 g/t.
Inhibition of REV‐ERBs stimulates microglial amyloid‐beta clearance and reduces amyloid plaque deposition in the 5XFAD mouse model of Alzheimer’s disease
Authors: Lee Jiyeon , Kim Do Eon , Griffin Percy , Sheehan Patrick W. , Kim Dong‐Hou , Musiek Erik S , Yoon Seung‐Yong 
Published: December 2019

AbstractA promising new therapeutic target for the treatment of Alzheimer's disease (AD) is the circadian system. Although patients with AD are known to have abnormal circadian rhythms and suffer sleep disturbances, the role of the molecular clock in regulating amyloid‐beta (Aβ) pathology is still poorly understood. Here, we explored how the circadian repressors REV‐ERBα and β affected Aβ clearance in mouse microglia. We discovered that, at Circadian time 4 (CT4), microglia expressed higher levels of the master clock protein BMAL1 and more rapidly phagocytosed fibrillary Aβ1‐42 (fAβ1‐42) than at CT12. BMAL1 directly drives transcription of REV‐ERB proteins, which are implicated in microglial activation. Interestingly, pharmacological inhibition of REV‐ERBs with the small molecule antagonist SR8278 or genetic knockdown of REV‐ERBs‐accelerated microglial uptake of fAβ1‐42 and increased transcription of BMAL1. SR8278 also promoted microglia polarization toward a phagocytic M2‐like phenotype with increased P2Y12 receptor expression. Finally, constitutive deletion of Rev‐erbα in the 5XFAD model of AD decreased amyloid plaque number and size and prevented plaque‐associated increases in disease‐associated microglia markers including TREM2, CD45, and Clec7a. Altogether, our work suggests a novel strategy for controlling Aβ clearance and neuroinflammation by targeting REV‐ERBs and provides new insights into the role of REV‐ERBs in AD.
Chorionic villus sampling experience of a reference perinatal medicine center
Authors: Beksaç M. Sinan , Unal Canan , Tanacan Atakan , Fadiloglu Erdem , Çakar Ayşe Nur 
Published: December 2019

AbstractAimTo share the chorionic villus sampling (CVS) experience of a single surgeon in our institution.MethodsThis retrospective study consists of CVS cases performed between 2000 and 2018. A total of 66 types of indications were classified under two main categories, the screening group (SG) and the inherited disease group (IDG). The SG and IDG were compared in terms of clinical characteristics of the patients, Beksaç obstetrics index (BOI), timing of CVS in terms of gestational week, and complications and termination of pregnancy (TOP) rate.ResultsCVS was performed at 656 women, 69 and 587 of whom were included in the SG and IDG, respectively. CVS indications of the SG were determined as advanced maternal age, high risk in combined test, fetal anomaly suspicion in ultrasonography, and increased nuchal translucency in 23, 23, 14 and 9 cases, respectively. On the other hand, CVS indications of the IDG were hereditary disorders related to hematological, muscular, and metabolic systems for 233, 179, and 116 cases, respectively. Furthermore, 32 patients had a single‐gene disorder and 14 had a neurodegenerative disease. According to the results of CVS, 359 fetuses were found to be normal (54.73%), while 205 (31.25%) and 92 (14.02%) fetuses were found to be disorder‐positive or carriers, respectively. Two hundred pregnant women accepted TOP. Eight (1.2%) pregnancies ended with abortion after CVS. Statistically significant differences were observed in BOI and TOP rate between SG and IDG (p: 0.042 and 0.013).ConclusionHereditary disorders were the most common CVS indications and the acceptance of TOP was significantly higher in this group.
Does the @realDonaldTrump Really Matter to Financial Markets?
Authors: Benton Allyson L. , Philips Andrew Q. 
Published: December 2019

AbstractDoes the @realDonaldTrump really matter to financial markets? Research shows that new information about the likely future policy direction of government affects financial markets. In contrast, we argue that new information can also arise about the likely future government's resolve in following through with its policy goals, affecting financial markets as well. We test our argument using data on U.S. President Donald J. Trump's Mexico‐related policy tweets and the U.S. dollar/Mexican peso exchange rate. We find that Trump's Mexico‐related tweets raised Mexican peso volatility while his policy views were unknown as well as thereafter, as they signaled his resolve in carrying out his Mexico‐related agenda. By helping politicians disseminate policy information to voters, and since voters hold governments accountable for their policy performance, social media allows investors to gather information about the likely policy direction and policy resolve of government, especially those of newcomers whose direction and resolve are unknown.