bluuebunny/crossref_metadata_2025 huggingface dataset:
Corrosion behavior of X80 steel under disbond coating interfered with AC
Authors: Ding Qingmiao , Li Zili , Shen Tao , Cui Gan
Published: September 2019

Purpose

This paper aims to research the corrosion behavior of the metal under the disbonded coatings interfered with AC through electrochemical method.

Design/methodology/approach

The corrosion behavior of the metal under disbond coating interfered with alternate stray current (AC) was studied by electrochemical methods using the rectangular coating disbonded simulator. The obtained data from electrode potential test, electrochemical impedance spectroscopy (EIS) and polarization curves in simulated soil solution indicated that under the natural corrosion condition, the self-corrosion potential and the corrosion current density of the metal at different depths under disbond coating had obviously changed if there was AC interference.

Findings

The self-corrosion potential of the metal at the same depths under disbond coating shifted negatively with the rising of the AC voltage. Under the condition of cathode polarization, there was still obvious potential gradient with the extension of the deep peeling of the coating gap, and the corrosion current density of the test points was minimum, and the protection effect was best when the cathode protection potential was −1.0 V. When the metal was applied with over-protection, the corrosion rate of the metal increased as AC stray current flowing through it increased.

Originality/value

This paper used the rectangular aperture device to study the corrosion behavior of X80 steel under the disbonded coatings through electrochemical methods when the AC stray current interference voltage was 0V, 1V, 5V or 10V and the protection potential was 0V, −0.9V, −1.0V, −1.2V or −1.3V, respectively. There is great significance to the safe operation and long-term service of pipeline steel in soil environment.
An 8kW LLC resonant converter in plasma power supply based on SiC power devices for efficiency improvement
Authors: Wang Zhenmin , Fan Wenyan , Xie Fangxiang , Ye Chunxian
Published: September 2019

Purpose

This paper aims to present an 8 kW LLC resonant converter designed for plasma power supply with higher efficiency and lighter structure. It presents how to solve the problems of large volume and weight, low performance and low efficiency of traditional plasma power supply.

Design/methodology/approach

At present, conventional silicon (Si) power devices’ switching performance is close to the theoretical limit determined by its material properties; the next-generation silicon carbide (SiC) power devices with outstanding advantages can be used to optimal design. This 8 kW LLC resonant converter prototype with silicon carbide (SiC) power devices with a modulated switching frequency ranges from 100  to 400 kHz.

Findings

The experimental results show that the topology, switching loss, rectifier loss, transformer loss and drive circuit of the full-bridge LLC silicon carbide (SiC) plasma power supply can be optimized.

Research limitations/implications

Due to the selected research object (plasma power supply), this study may have limited universality. The authors encourage the study of high frequency resonant converters for other applications such as argon arc welding.

Practical implications

This study provides a practical application for users to improve the quality of plasma welding.

Originality/value

The experimental results show that the full-bridge LLC silicon carbide (SiC) plasma power supply is preferred in operation under conditions of high frequency and high voltage. And its efficiency can reach 98%, making it lighter, more compact and more efficient than previous designs.
External career mentoring and mentor turnover intentions
Authors: Renn Robert W. , Steinbauer Robert , Huning Tobias Michael
Published: September 2019

Purpose

Although studies have improved understanding of the relation between external career mentoring and mentor work outcomes, an important question remains regarding whether this mentoring function influences mentor turnover intentions. The purpose of this paper is to investigate the impact of career mentoring outside the workplace on mentor turnover intentions.

Design/methodology/approach

Data were collected from 101 working business professionals in the southeastern USA at two points in time who provided career mentoring to business student protégés in an eight-month university sponsored mentoring program.

Findings

As hypothesized, moderated mediation analysis indicated that amount of external career mentoring negatively related to mentor turnover intentions and that the indirect effect of external career mentoring on mentor turnover intentions via mentor work engagement was stronger when both mentor protégé satisfaction and meeting frequency were high vs low. A two-way interaction revealed that mentors reporting higher protégé satisfaction had lower turnover intentions when meeting frequency was high vs low.

Originality/value

The findings help clarify the external career mentoring and mentor turnover intentions relation and have valuable theoretical implications for research on the benefits external mentoring can provide mentors. They also have practical implications for using external mentoring to enhance mentor work engagement and reduce mentor turnover intentions.
Fast multi-objective design optimization of microwave and antenna structures using data-driven surrogates and domain segmentation
Authors: Koziel Slawomir , Bekasiewicz Adrian
Published: September 2019

Purpose

The purpose of this paper is to investigate the strategies and algorithms for expedited design optimization of microwave and antenna structures in multi-objective setup.

Design/methodology/approach

Formulation of the multi-objective design problem-oriented toward execution of the population-based metaheuristic algorithm within the segmented search space is investigated. Described algorithmic framework exploits variable fidelity modeling, physics- and approximation-based representation of the structure and model correction techniques. The considered approach is suitable for handling various problems pertinent to the design of microwave and antenna structures. Numerical case studies are provided demonstrating the feasibility of the segmentation-based framework for the design of real-world structures in setups with two and three objectives.

Findings

Formulation of appropriate design problem enables identification of the search space region containing Pareto front, which can be further divided into a set of compartments characterized by small combined volume. Approximation model of each segment can be constructed using a small number of training samples and then optimized, at a negligible computational cost, using population-based metaheuristics. Introduction of segmentation mechanism to multi-objective design framework is important to facilitate low-cost optimization of many-parameter structures represented by numerically expensive computational models. Further reduction of the design cost can be achieved by enforcing equal-volumes of the search space segments.

Research limitations/implications

The study summarizes recent advances in low-cost multi-objective design of microwave and antenna structures. The investigated techniques exceed capabilities of conventional design approaches involving direct evaluation of physics-based models for determination of trade-offs between the design objectives, particularly in terms of reliability and reduction of the computational cost. Studies on the scalability of segmentation mechanism indicate that computational benefits of the approach decrease with the number of search space segments.

Originality/value

The proposed design framework proved useful for the rapid multi-objective design of microwave and antenna structures characterized by complex and multi-parameter topologies, which is extremely challenging when using conventional methods driven by population-based metaheuristics algorithms. To the authors knowledge, this is the first work that summarizes segmentation-based approaches to multi-objective optimization of microwave and antenna components.
Employees’ perceptions of human resource management practices and employee outcomes
Authors: Li Shaoheng , Rees Christopher J. , Branine Mohamed
Published: September 2019

Purpose

The purpose of this paper is to examine the relationship between employees’ perceptions of HRM practices and two outcomes, namely, employee commitment and turnover intention (TI), in small- and medium-sized enterprises (SMEs) in mainland China.

Design/methodology/approach

This paper adopts a quantitative approach based on a sample of 227 employees working in 24 SMEs in eastern and western China.

Findings

Employees’ perceptions of HRM practices, such as training and development, reward management and performance management, are significant predictors of employee commitment. A negative direct relationship is found between employees’ perceptions about the use of HRM practices and TIs.

Research limitations/implications

Although data were collected from two representative provinces of eastern and western China, the size of the sample may limit the generalisability of the findings to the wider region.

Practical implications

The relationship between employees’ perceptions of HRM practices and employee outcomes in Chinese SMEs provides an effective way for SME owners and HR practitioners to generate desirable employee attitudes and behaviours, which, ultimately contribute to improving organisational performance.

Originality/value

This is an original paper which makes a contribution by helping to address the dearth of studies which have explored aspects of the effectiveness of HRM in SMEs in China. In contrast to the majority of China-focussed studies on this topic, it highlights HRM outcomes at the individual level rather than the organisational level. Further, the study involves SMEs in western China which is an under-explored region.
Numerical simulation of droplet dynamics on chemically heterogeneous surfaces by lattice Boltzmann method
Authors: Wang Xin , Xu Bo , Chen Z.
Published: September 2019

Purpose

This paper aims to investigate spontaneous movement of single droplet on chemically heterogeneous surfaces induced by the net surface tension, using the improved three-dimensional (3D) lattice Boltzmann (LB) method.

Design/methodology/approach

D3Q19 Shan-Chen LB model is improved in this paper. Segmented particle distribution functions coupled with the P-R equation of state are introduced to maintain the higher accuracy and greater stability. In addition, exact difference method (EDM) is adopted to implement force term to predict the droplet deformation and dynamics.

Findings

The numerical results demonstrate that spontaneous movement of single droplet (=1.8 µm) along wedge-shaped tracks is driven by net surface tension. Advancing angle decreases instantaneously with time, while receding angle changes slightly first and then decreases rapidly. Wetting length is affected by vertex angle and wetting difference, whereas the final value is only dependent on the stronger wettability. Although the velocity of single droplet on wedge-shaped tracks can be increased by the larger vertex angle, it has a negative influence on the displacement. For the same wetting difference, vertex angle equal to 30º is an optimization strategy in this model. If the simulation length is extended enough, then the smaller vertex angle is beneficial for the droplet movement. In addition, a larger wetting difference is beneficial to spontaneous movement, which can speed up the droplet movement.

Originality/value

The proposed numerical model of droplet dynamics on chemically heterogeneous surfaces provides fundamental insights for the enhancement of drop-wise condensation heat transfer.
Multiple-relaxation-time lattice Boltzmann model for simulation of free convection in axisymmetric nanofluid-filled annulus-experimental and numerical observations
Authors: Sun Heng , Ross David
Published: September 2019

Purpose

The MRT lattice Boltzmann simulation of natural convection in a confined environment is carried out. The flow and heat transfer during natural convection in a symmetrical annulus are studied.

Design/methodology/approach

The cavity is filled with TiO2-water nanofluid, and the thermal conductivity and dynamic viscosity of nanofluid are measured experimentally. The experimental data are utilized in the numerical simulations. The nanofluids are prepared at four different nanoparticle concentrations φ = 0, 0.1, 0.3 and 0.5. It is notable that the radial coordinate is used into the temperature distribution function. As a result, only one source term is required for the present lattice Boltzmann model. On the other hand, the macro cylindrical energy equation is exactly recovered using Chapman–Enskog analysis.

Findings

Influence of some main parameters including Rayleigh number in range of 103 to 106, solid volume fraction of nanofluid in range of 0 to 0.5 and four different aspect ratios on the the nanofluid flow (i.e. streamlines), heat transfer (i.e. temperature distribution and average Nusselt number) and entropy generation (i.e. total entropy generation and Bejan number) are presented, quantitatively and graphically. It is found that adding TiO2 nanoparticles to the base fluid has considerable positive effect on the heat transfer performance and entropy generation. In addition, the configuration of the annulus can be good controlling parameter on the heat transfer rate during natural convection.

Originality/value

The originality of this work is using of a modern numerical method to simulate the free convection and conducting experimental observations to calculate the thermo-physical properties of nanofluid. In addition, the numerical and experimental works are combined to provide accurate results.
Microbreweries, brewpubs and beerfirms in the Sicilian craft beer industry
Authors: Alfeo Vincenzo , Todaro Aldo , Migliore Giuseppina , Borsellino Valeria , Schimmenti Emanuele
Published: September 2019

Purpose

This paper aims to illustrate the organisational and managing models characterising the craft beer producers in Sicily (Southern Italy) and the main issues of the provision of raw materials.

Design/methodology/approach

A direct survey involving the overall population of 41 craft breweries operating in Sicily in 2016 was carried out. Then 29 questionnaires were collected for exploratory analysis. A hierarchical cluster analysis was also performed out to group companies by similar structural, productive and economic features.

Findings

The findings of the survey showed a Sicilian craft beer industry characterised by a substantial dependence on the import of malts hops and yeasts and the limited use of local raw materials among brewers. Furthermore, the characteristics of the processing plants and the sales channels appear to influence the diversification of the products and the turnover levels of the Sicilian craft beer producers.

Originality/value

This is the first study describing the craft brewing industry in Sicily. The findings contribute to enrich the knowledge on the organisational models applied in the craft beer industry. In particular, the findings could contribute to shed light on some critical issues about the provision of raw materials, suggesting possible paths for the successful development of the craft beer industry in the region.
Chasing Frankenstein’s monster: information literacy in the black box society
Authors: Lloyd Annemaree
Published: September 2019

Purpose

The purpose of this paper is to introduce and examine algorithmic culture and consider the implications of algorithms for information literacy practice. The questions for information literacy scholars and educators are how can one understand the impact of algorithms on agency and performativity, and how can one address and plan for it in their educational and instructional practices?

Design/methodology/approach

In this study, algorithmic culture and implications for information literacy are conceptualised from a sociocultural perspective.

Findings

To understand the multiplicity and entanglement of algorithmic culture in everyday lives requires information literacy practice that encourages deeper examination of the relationship among the epistemic views, practical usages and performative consequences of algorithmic culture. Without trying to conflate the role of the information sciences, this approach opens new avenues of research, teaching and more focused attention on information literacy as a sustainable practice.

Originality/value

The concept of algorithmic culture is introduced and explored in relation to information literacy and its literacies.
Genres and situational appropriation of information
Authors: Huvila Isto
Published: September 2019

Purpose

Information science research has begun to broaden its traditional focus on information seeking to cover other modes of acquiring information. The purpose of this paper is to move forward on this trajectory and to present a framework for explicating how in addition to being sought, existing information are made useful and taken into use.

Design/methodology/approach

A conceptual enquiry draws on an empirical vignette based on an observation study of an archaeological teaching excavation. The conceptual perspective builds on Andersen’s genre approach and Huvila’s notion of situational appropriation.

Findings

This paper suggests that information becomes appropriable, and appropriated (i.e. taken into use), when informational and social genres intertwine with each other. This happens in a continuous process of (re)appropriation of information where existing information scaffolds new information and the on-going process of appropriation.

Originality/value

The approach is proposed as a potentially powerful conceptualisation for explicating information interactions when existing information is taken into use rather than sought that have received little attention in traditional models and theories of human information behaviour.
Using collaborative research methodologies in humanitarian supply chains
Authors: Sabri Yasmine , Zarei Mohammad Hossein , Harland Christine
Published: September 2019

Purpose

The purpose of this paper is to develop an existing collaborative research methodology process (Sabri, 2018), contextualise it for application in humanitarian supply chains and test it empirically.

Design/methodology/approach

Building on collaborative research methodology and humanitarian supply chain literature, the Sabri’s (2018) collaborative research methodology process is further developed to comprise eight phases of collaborative research contextualised for the humanitarian supply chain domain. The process is applied in a collaborative research case of academia–practitioner knowledge co-creation in a humanitarian supply chain setting, focussing on environmental sustainability improvement. The collaborative case analysis suggests a number of refinements to the elements of the process. This study undertook two cycles of academia–practitioner collaborative research.

Findings

In testing the process, a noticeable improvement in the collaboration among different humanitarian stakeholders was observed, leading to improved stakeholder management. The implementation improved the sustainability awareness and social inclusion of the affected population. Rurality, remoteness, security issues and resistance of field staff against change were among the main challenges for supply chain researchers to engage in collaborative research in the humanitarian domain.

Originality/value

The paper addresses the rigour‒relevance‒reflectiveness debate in the humanitarian supply chain domain. A collaborative research methodology process derived from action research is further developed using humanitarian literature, and then it is applied in a humanitarian logistics case focussed on environmental sustainability. The present collaborative research process facilitates engaged scholarship among the humanitarian stakeholders, as the researchers’ roles move from observatory to participatory knowledge broker.
A problematic legacy: diversity in American reading textbooks
Authors: Compton-Lilly Catherine , Liu Shuning , Padrós Cuxart Maria , Pettit Lindsay , Timm Yanli
Published: September 2019

Purpose

This conceptual paper aims to explore biases in reading textbooks that have been used to teach generations of Americans, including children in urban communities. While these texts are no longer used, the images they present and the ideas embedded in these texts unfortunately contribute to who we are as a nation.

Design/methodology/approach

These texts were identified by Catherine Compton-Lilly as she trolled the historical archives of a major university.

Findings

In addition to an analysis of historic texts, more recent attempts to create culturally responsive texts often designed to serve children in urban communities are examined, and the learnings from these attempts are being explored.

Practical implications

This conceptual paper points to the need for systematic analyses of biases operating in textbooks that are currently used in schools.

Originality/value

This work reveals and explores one way in which historical bias has historically infected the early learning experiences of young children in the USA.
Visibility and growth of LIS research publications: a Scopus based analysis of select open access journals during 2001 to 2015
Authors: Barik Nilaranjan , Jena Puspanjali
Published: September 2019

Purpose

This study aims to establish an idea on visibility and growth of research publications of select Library and Information Science (LIS) open access journals indexed in Scopus database during the period 2001-2015.

Design/methodology/approach

The study covers its scope to the research publications published during the period 2001-2015. All retrieved data were analyzed using bibliometric methods. The data of the select journals were searched in Scopus database using the name of the journal as search term in source of the database.

Findings

The results of the study reveal that visibility of LIS research articles in country based, university/ institution based, types of document based, authors based and citation based is significant. Authors from 83 countries and 990 universities/ institutions across the world have published their research in such LIS open access journals. The American and European countries are the leaders among all contributing countries and “Article” is the most popular types of documents with 61.37 per cent publications. The citation impact of publications shows an average 8.08 citations per publication.

Originality/value

The study raises concern on the global visibility of LIS research publications. Authors from underdeveloped countries do not prefer to publish their publications in open channel. Also government and other research bodies of these countries do not give proper weightage to the publications in open access journals. So, the study intends to assess the visibility of LIS research publications and their growth pattern.
Ethical leadership and employee in-role performance
Authors: Kia Narges , Halvorsen Beni , Bartram Timothy
Published: September 2019

Purpose

Against the backdrop of the Royal Commission into Misconduct in the Banking, Superannuation and Finance Services Industry in Australia, this study on ethical leadership is timely. The purpose of this paper is to examine the mediating effects of organisational identification, customer orientated behaviour, service climate and ethical climate on the relationship between ethical leadership and employee in-role performance.

Design/methodology/approach

The hypotheses were tested using a two-wave survey study of 233 bank employees in Australia.

Findings

Evidence from the study indicated that organisational identification, service climate and ethical climate mediate the relationship between ethical leadership and employee in-role performance. Surprisingly, the proposed mediation effect of customer orientation was not supported. However, ethical leadership was positively associated with customer orientated behaviour among employees.

Research limitations/implications

Limitations of the study include collecting data at two time points, thereby rendering the study cross-sectional. Employee in-role performance was a self-rated measure.

Practical implications

This study showed that ethical leadership is critical to improving employee perceptions and experience of an organisation’s service climate, ethical climate, organisational identification, customer orientated behaviour and employee in-role performance. The authors raise a number of HRM implications for the development and enablement of ethical leaders in the banking context.

Originality/value

The findings presented in this paper highlight that ethical leadership is critical to improving employee perceptions and experience of an organisation’s service climate, ethical climate, organisational identification, customer orientated behaviour and employee in-role performance.
Skewed macrophage polarization in aging skeletal muscle
Authors: Cui Chang‐Yi , Driscoll Riley K. , Piao Yulan , Chia Chee W. , Gorospe Myriam , Ferrucci Luigi
Published: September 2019

Skeletal muscle aging is a major cause of disability and frailty in the elderly. The progressive impairment of skeletal muscle function with aging was recently linked to a disequilibrium between damage and repair. Macrophages participate in muscle tissue repair, first as pro‐inflammatory M1 subtype and then as anti‐inflammatory M2 subtype. However, information on the presence of macrophages in skeletal muscle is still sporadic and the effect of aging on macrophage phenotype remains unknown. In this study, we sought to characterize the polarization status of macrophages in skeletal muscle of persons across a wide range of ages. We found that most macrophages in human skeletal muscle are M2, and that this number increased with advancing age. On the contrary, M1 macrophages declined with aging, making the total number of macrophages invariant with older age. Notably, M2 macrophages colocalized with increasing intermuscular adipose tissue (IMAT) in aging skeletal muscle. Similarly, aged BALB/c mice showed increased IMAT and M2 macrophages in skeletal muscle, accompanied by slightly increased collagen protein production. Collectively, we report that polarization of macrophages to the major M2 subtype is associated with IMAT and propose that increased M2 in aged skeletal muscle may impact upon muscle metabolism associated with aging.
Cost‐effectiveness of expanding the capacity of opioid agonist treatment in Ukraine: dynamic modeling analysis
Authors: Morozova Olga , Crawford Forrest W. , Cohen Ted , Paltiel A. David , Altice Frederick L.
Published: September 2019

Background and aims

Although opioid agonist treatment (OAT) for opioid use disorder (OUD) is cost‐effective in settings where the HIV epidemic is concentrated among people who inject drugs, OAT coverage in Ukraine remains far below internationally recommended targets. Scale‐up is limited by both OAT availability and demand. This study aimed to evaluate the cost‐effectiveness of a range of plausible OAT scale‐up strategies in Ukraine incorporating the potential impact of treatment spillover and the real‐world demand for addiction treatment.

Design, setting and participants

Ten‐year horizon (2016–25) modeling study of opioid addiction epidemic and treatment that accommodated potential peer effects in opioid use initiation and supply‐induced treatment demand in three Ukrainian cities: Kyiv, Mykolaiv and Lviv, comprising a simulated population of people at risk of and with OUD.

Measurements

Incremental cost per quality‐adjusted life‐year gained in the simulated population.

Findings

An estimated 12.2‐, 2.4‐ and 13.4‐fold OAT capacity increase over 2016 baseline capacity in Kyiv, Mykolaiv and Lviv, respectively, would be cost‐effective at a willingness‐to‐pay of one per‐capita gross domestic product (GDP) per quality‐adjusted life‐year gained. This result is robust to parametric and structural uncertainty. Even under the most ambitious capacity increase, OAT coverage (i.e. the proportion of people with OUD receiving OAT) over a 10‐year modeling horizon would be 20, 11 and 17% in Kyiv, Mykolaiv and Lviv, respectively, owing to limited demand.

Conclusions

It is estimated that a substantial increase in opioid agonist treatment (OAT) capacity in three Ukrainian cities would be cost‐effective for a wide range of willingness‐to‐pay thresholds. Even a very ambitious capacity increase, however, is unlikely to reach internationally recommended coverage levels. Further increases in coverage may be limited by demand and would require addressing existing structural barriers to OAT access.
Land Reform and Civil Conflict: Theory and Evidence from Peru
Authors: Albertus Michael
Published: September 2019

How does land reform impact civil conflict? This article examines this question in the prominent case of Peru by leveraging original data on all land expropriations under military rule from 1969 to 1980 and event‐level data from the Peruvian Truth and Reconciliation Commission on rural killings during Peru's internal conflict from 1980 to 2000. Using a geographic regression discontinuity design that takes advantage of Peru's regional approach to land reform through zones that did not entirely map onto major preexisting administrative boundaries, I find that greater land reform dampened subsequent conflict. Districts in core areas of land reform zones that received intense land reform witnessed less conflict relative to comparable districts in adjacent peripheral areas where less land reform occurred. Further tests suggest that land reform mitigated conflict by facilitating counterinsurgency and intelligence gathering, building local organizational capacity later used to deter violence, undercutting the Marxist left, and increasing opportunity costs to supporting armed groups.
Sequence analysis of 37 candidate genes for male infertility: challenges in variant assessment and validating genes
Authors: Araujo T. F. , Friedrich C. , Grangeiro C. H. P. , Martelli L. R. , Grzesiuk J. D. , Emich J. , Wyrwoll M. J. , Kliesch S. , Simões A. L. , Tüttelmann F.
Published: September 2019

Background

The routine genetic analysis for diagnosing male infertility has not changed over the last twenty years, and currently available tests can only determine the etiology of 4% of unselected infertile patients. Thus, to create new diagnostic assays, we must better understand the molecular and genetic mechanisms of male infertility. Although next‐generation sequencing allows for simultaneous analysis of hundreds of genes and the discovery of novel candidates related to male infertility, so far only a few gene candidates have enough sound evidence to support the gene–disease relationship.

Objective

Since complementary studies are required to validate genes, we aimed to analyze the presence of potentially pathogenic rare variants in a set of candidate genes related to azoospermia in a hitherto understudied South American population.

Subjects and Methods

We performed whole exome sequencing in a group of 16 patients with non‐obstructive azoospermia from Ribeirão Preto, Brazil. Based on a recent systematic review of monogenic causes of male infertility, we selected a set of 37 genes related to azoospermia, Sertoli‐Cell‐Only histology, and spermatogenic arrest to analyze. The identified variants were confirmed by Sanger sequencing, and their functional consequence was predicted by in silico programs.

Results

We identified potential pathogenic variants in seven genes in six patients. Two variants, c.671A>G (p.(Asn224Ser)) in DMRT1 and c.91C>T (p.(Arg31Cys)) in REC8, have already been described in association with azoospermia. We also found new variants in genes that already have moderate evidence of being linked to spermatogenic failure (TEX15, KLHL10), in genes with limited evidence (DNMT3B, TEX14) and in one novel promising candidate gene that has no evidence so far (SYCE1L).

Discussion

Although this study included a small number of patients, the process of rationally selecting genes allowed us to detect rare potentially pathogenic variants, providing supporting evidence for validating candidate genes associated with azoospermia.
Factors associated with the decision for operative versus conservative treatment of displaced distal radius fractures in the elderly
Authors: Wu Yao‐Sen , Yang Jie , Xie Lin‐Zhen , Zhang Jia‐Yu , Yu Xian‐Bin , Hu Wei , Chen Hua , Sun Liao‐Jun
Published: September 2019

Background

The treatment of senile distal radius fractures had not been clearly defined. The objective of this study was to identify the factors associated with the decision for operative treatment of displaced distal radius fractures in patients aged over 55 years.

Methods

Data of 318 patients with displaced distal radius fractures were collected on patient‐, fracture‐ and surgeon‐related characteristics that were plausibly related to the decision for operation. Mean comparisons or chi‐squared test were used for univariate analysis of the above‐mentioned factors, and then multiple logistic regression was used to identify factors associated with the decision for operation.

Results

Univariate analysis showed that age, osteoporosis, Charlson score, associated orthopaedic injuries requiring surgery, Orthopaedic Trauma Association (AO) and Fernandez classification, radial height, volar tilt, volar/dorsal comminution, ulnar variance, intra‐articular displacement/step‐off, associated distal radioulnar joint instability or radiocarpal joint dislocation and subspecialty of treating surgeons had statistically significant association with operative intervention. In the multivariate analysis, the predictors of operative intervention were younger patient age (P = 0.028), associated orthopaedic injuries requiring surgery (P = 0.020), higher AO classification (P = 0.037), higher Fernandez classification (P = 0.041), radial shortening >5 mm (P = 0.020), volar tilt > −10° (P = 0.020), volar/dorsal comminution (P = 0.020), ulnar variance >5 mm (P = 0.023), intra‐articular displacement/step‐off >2 mm (P = 0.004), associated distal radioulnar joint instability or radiocarpal joint dislocation (P = 0.047) and treatment by an upper extremity specialist (P = 0.038).

Conclusion

The decision for surgery was predominantly influenced by the characteristics and severity of the fracture. Patients' age and treatment by an upper extremity specialist were also significant factors associated with a higher likelihood of operative intervention.
Mechanisms underlying the inhibitory effects of probucol on elastase‐induced abdominal aortic aneurysm in mice
Authors: Chen Cong , Wang Yunxia , Cao Yini , Wang Qinyu , Anwaier Gulinigaer , Zhang Qingyi , Qi Rong
Published: September 2019

Background and Purpose

Abdominal aortic aneurysm (AAA) is a degenerative disease with irreversible and progressive dilation of the artery. But there are few options for efficacious treatment except for traditional surgery. Probucol has been widely applied to treat hyperlipidaemia and atherosclerosis in clinic, but whether it can protect against AAA remains unknown. In this study, the protective effects of probucol against AAA and its related mechanisms were explored.

Experimental Approach

The model of AAA was induced in mice by periaortic application of elastase (40 min) to the abdominal aorta. Probucol at different doses was administered by daily gavage, starting on the same day as AAA was induced, for 14 days. In vitro, cultures of rat vascular smooth muscle cells (VSMCs) were stimulated with TNF‐α. Haem oxygenase (HO)‐1 siRNA and HO‐1 plasmid were used to regulate the expression or activity of HO‐1 in the VSMCs and to clarify the effects of HO‐1.

Key Results

Probucol dose‐dependently prevented the development of AAA, reflected by decreased incidence of AAA, diameter of aortic dilation, elastin degradation, and infiltration of inflammatory cells. Probucol also protected VSMCs from oxidative injury and enhanced elastin biosynthesis. This anti‐inflammatory effects of probucol on VSMCs were significantly decreased when HO‐1 was inhibited by siRNA.

Conclusion and Implications

Probucol protected against AAA through inhibiting the degradation of elastin induced by inflammation and oxidation and by facilitating the biosynthesis of elastin. HO‐1 played a crucial role in the anti‐inflammatory effects of probucol in VSMCs.
Known and estimated distribution in Mexico of Batrachochytrium dendrobatidis, a pathogenic fungus of amphibians
Authors: Bolom‐Huet René , Pineda Eduardo , Díaz‐Fleischer Francisco , Muñoz‐Alonso Antonio L. , Galindo‐González Jorge
Published: September 2019

Chytridiomycosis caused by fungus Batrachochytrium dendrobatidis (Bd) is one of the decline global causes of amphibians. Currently, it is distributed throughout a broad range of climates and ecosystems around the world. An epidemic wave of chytridiomycosis began in North America, resulting in population decline and local extinction of many species, reconfiguring species composition of amphibian communities in the Americas. In Mexico, Bd has caused an amphibian population decrease, and its potential distribution area has not been determined. We reviewed the number of species infected, obtaining Bd frequency of infection by land use and vegetation type, and by elevation range. We examined the known distribution of Bd, estimated the potential distribution, and obtained the bioclimate variables relevant for Bd. Our results indicate that in Mexico, Bd has been detected in 78 species of amphibians in 10 families, from 29 different land use and vegetation types, with cloud forest having the highest number of cases (139) and infected species (15). Bd occurs over an elevation range of 1–3,300 m asl and is most frequent at 1,200–1,500 m asl (36%). In addition to the regions previously described as suitable for Bd, our model included desert, coastal, and tropical forest regions, revealing an increase in the area where amphibians could be at risk of infection. Distribution of Bd is mainly associated with temperature of the wettest quarter and potential evapotranspiration of the warmer quarter. We offer an estimate of the ideal conditions for Bd in Mexico, also information for future studies on Bd and the conservation of amphibians.

Abstract in Spanish is available with online material.
Minimally invasive parathyroid carcinoma—A missing entity between parathyroid adenoma and carcinoma: Scintigraphic and histological features
Authors: Singh Priyanka , Vadi Shelvin Kumar , Saikia Uma Nahar , Sood Ashwani , Dahiya Divya , Arya Ashutosh Kumar , Behera Arunanshu , Mukherjee Soham , Arvindkumar Sapara Mohin , Bhadada Sanjay Kumar
Published: September 2019

Purpose

Minimally invasive parathyroid carcinoma (MIPC) is clinically and biochemically comparable with parathyroid adenoma (PA) though histopathologically differ from PA. MIPC is an intermediate of PA and parathyroid carcinoma (PC). In literature, there is no definite criterion to diagnose MIPC. Our aim was to evaluate and characterize the imaging and biochemical parameters with histological characteristics of MIPC.

Methodology

Ten patients with MIPC were recruited from (single centre) Indian PHPT registry (www.indianphptregistry.com) from January 2014 to July 2018. Clinical, biochemical, imaging and histological features of MIPC patients were reviewed.

Results

The mean age of MIPC patients (n = 10; 3 males) was 39.9 ± 11.3 years (range: 17‐50). All patients had an elevated preoperative parathyroid hormone (iPTH) level ranging from 427 to 2138 pg/mL (median: 1328). MIBI scan showed intensely avid and enlarged parathyroid tumours in all patients; LIPT in 6, RIPT in 3 and ectopic mediastinal in 1 with mean size of the tumours was 2.8 ± 1.1 cm. The mean of maximum standardized uptake value (SUVmax) of MIPC in F‐18 fluorocholine PET/CT was 6.7 ± 1.1 (range 6.0‐8.3). The mean tumour weight was 12 ± 9.5 g (range: 1.09‐28). All MIPC patients had identified capsular invasion in 80% and vascular invasion in 50% only but there was no local invasion, lymph nodal or distant metastasis. The mean Ki‐67 labelling index was 3.2 ± 2.7 (range 1.1‐10).

Conclusion

The study concluded that MIPC patients are less aggressive (on the basis of imaging and histopathological findings) and should be differentiated from parathyroid adenoma and carcinoma.
Habitat‐specific impacts of climate change in the Mata Atlântica biodiversity hotspot
Authors: Esser Luíz Fernando , Neves Danilo M. , Jarenkow João André
Published: September 2019

Aim

Elucidate the potential impacts of climate changes on the distribution and conservation of the multiple habitats of the Mata Atlântica biodiversity hotspot, which are often treated as a unique entity in ecological studies.

Location

The whole extension of the South American Atlantic Forest Domain plus forest intrusions into the neighbouring Cerrado and Pampa Domains, which comprises rain forest (‘core’ habitat) and five environmentally marginal habitats, namely high elevation/latitude forest, rock outcrop habitats, riverine forest, semideciduous forest and restinga woodlands.

Time period

Current (2000) and future scenarios (2050 and 2070).

Major taxa studied

Tree species.

Methods

We modelled the responses of 282 diagnostic tree species, using multiple algorithms and distinct scenarios of climate change (828,234 projections).

Results

Potential loss of suitable environment summed 50.4% in semideciduous forest, 58.6% in riverine forest and 66% in rock outcrop habitats. Predictions for rain forest (12.2%), restinga woodlands (7.6%) and high elevation/latitude forest (5.2%) showed that overall loss of suitable environment will be relatively less severe for these habitats. Habitats that are confined to narrow edaphic conditions, namely rock outcrop habitats and riverine forest, are less studied and will likely suffer the greatest loss of biodiversity because their species are more dispersal limited.

Main conclusions

Because these habitats occupy distinct environmental conditions, lumping them in ecological analyses might lead to erroneous interpretations in studies aiming to evaluate the impacts of global change in the Mata Atlântica biodiversity hotspot. This reinforces the importance of our approach and urges for conservation strategies that account for habitat heterogeneity in the Mata Atlântica and other species‐rich environments.
Investor behaviour and reaching for yield: Evidence from the sterling corporate bond market
Authors: Czech Robert , Roberts‐Sklar Matt
Published: September 2019

We provide evidence on how corporate bond investors react to a change in yields, and how this behaviour differs in times of market‐wide stress. We also investigate ‘reaching for yield’ across investor types, as well as providing insights into the structure of the corporate bond market. Using proprietary sterling corporate bond transaction data, we show that insurance companies, hedge funds and asset managers are typically net buyers when corporate bond yields rise. Dealer banks clear the market by being net sellers. However, we find evidence for this behaviour reversing in times of stress for some investors. During the 2013 ‘taper tantrum’, asset managers were net sellers of corporate bonds in response to a sharp rise in yields, potentially amplifying price changes. At the same time, dealer banks were net buyers. Finally, we provide evidence that insurers, hedge funds and asset managers tilt their portfolios towards higher risk bonds, consistent with ‘reaching for yield’ behaviour.
Critically testing olivine‐hosted putative martian biosignatures in the Yamato 000593 meteorite—Geobiological implications
Authors: McLoughlin Nicola , Grosch Eugene G. , Vullum Per Erik , Guagliardo Paul , Saunders Martin , Wacey David
Published: September 2019

On rocky planets such as Earth and Mars the serpentinization of olivine in ultramafic crust produces hydrogen that can act as a potential energy source for life. Direct evidence of fluid–rock interaction on Mars comes from iddingsite alteration veins found in martian meteorites. In the Yamato 000593 meteorite, putative biosignatures have been reported from altered olivines in the form of microtextures and associated organic material that have been compared to tubular bioalteration textures found in terrestrial sub‐seafloor volcanic rocks. Here, we use a suite of correlative, high‐sensitivity, in situ chemical, and morphological analyses to characterize and re‐evaluate these microalteration textures in Yamato 000593, a clinopyroxenite from the shallow subsurface of Mars. We show that the altered olivine crystals have angular and micro‐brecciated margins and are also highly strained due to impact‐induced fracturing. The shape of the olivine microalteration textures is in no way comparable to microtunnels of inferred biological origin found in terrestrial volcanic glasses and dunites, and rather we argue that the Yamato 000593 microtextures are abiotic in origin. Vein filling iddingsite extends into the olivine microalteration textures and contains amorphous organic carbon occurring as bands and sub‐spherical concentrations <300 nm across. We propose that a martian impact event produced the micro‐brecciated olivine crystal margins that reacted with subsurface hydrothermal fluids to form iddingsite containing organic carbon derived from abiotic sources. These new data have implications for how we might seek potential biosignatures in ultramafic rocks and impact craters on both Mars and Earth.
The fertilization effect of global dimming on crop yields is not attributed to an improved light interception
Authors: Shao Liping , Li Gang , Zhao Qiannan , Li Yabing , Sun Yutong , Wang Weinan , Cai Chuang , Chen Weiping , Liu Ronghua , Luo Weihong , Yin Xinyou , Lee Xuhui
Published: September 2019

Global dimming, a decadal decrease in incident global radiation, is often accompanied with an increase in the diffuse radiation fraction, and, therefore, the impact of global dimming on crop production is hard to predict. A popular approach to quantify this impact is the statistical analysis of historical climate and crop data, or use of dynamic crop simulation modelling approach. Here, we show that statistical analysis of historical data did not provide plausible values for the effect of diffuse radiation versus direct radiation on rice or wheat yield. In contrast, our field experimental study of 3 years demonstrated a fertilization effect of increased diffuse radiation fraction, which partly offset yield losses caused by decreased global radiation, in both crops. The fertilization effect was not attributed to any improved canopy light interception but mainly to the increased radiation use efficiency (RUE). The increased RUE was explained not only by the saturating shape of photosynthetic light response curves but also by plant acclimation to dimming that gradually increased leaf nitrogen concentration. Crop harvest index slightly decreased under dimming, thereby discounting the fertilization effect on crop yields. These results challenge existing modelling paradigms, which assume that the fertilization effect on crop yields is mainly attributed to an improved light interception. Further studies on the physiological mechanism of plant acclimation are required to better quantify the global dimming impact on agroecosystem productivity under future climate change.