bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamics of hard rods with initial domain wall state
Authors: Doyon Benjamin , Spohn Herbert
Published: July 2017

Inspired by recent results on the non-equilibrium dynamics of many-body quantum systems, we study the classical hard rod problem in one dimension with initial domain wall condition. Hard rods are an integrable system, in the sense that for each velocity the density of particles is locally conserved. It was proven by Boldrighini et al (1983 J. Stat. Phys. 31 577) that on the hydrodynamic space-time scale, the fluid of hard rods satisfies Euler-type equations which comprise all conservation laws. We provide the general solution to these equations on the line, with an initial condition where the left and right halves are, asymptotically, in different states. The solution is interpreted as being composed of a continuum of contact discontinuities, one for each velocity. This is a classical counterpart of the transport problem solved recently in quantum integrable systems. We also discuss the Navier–Stokes (viscous) corrections, and study its effect on the broadening of the contact discontinuity and on entropy production.
4D nucleome Analysis Toolbox: analysis of Hi-C data with abnormal karyotype and time series capabilities
Authors: Seaman Laura , Rajapakse Indika
Published: July 2017

Motivation

The availability of powerful analysis tools will further understanding of genome organization and its relationship to phenotype in dynamical settings.

Results

The 4D Nucleome Analysis Toolbox (NAT) is a user-friendly and powerful MATLAB toolbox for time series analysis of genome-wide chromosome conformation capture (Hi-C) data and gene expression (RNA-seq). NAT can load and normalize data, define topologically associating domains, analyse translocations, produce visualization, and study time course data. We provide examples that include time series data sets and karyotypically abnormal cell lines demonstrating the flexibility of NAT.

Availability and implementation

https://github.com/laseaman/4D_Nucleome_Analysis_Toolbox
Topological Realizations of Line Arrangements
Authors: Ruberman Daniel , Starkston Laura
Published: July 2017

A venerable problem in combinatorics and geometry asks whether a given incidence relation may be realized by a configuration of points and lines. The classic version of this would ask for lines in a projective plane over a field. An important variation allows for pseudolines: embedded circles (isotopic to $\mathbb R\rm{P}^1$) in the real projective plane. In this article we investigate whether a configuration is realized by a collection of 2-spheres embedded, in symplectic, smooth, and topological categories, in the complex projective plane. We find obstructions to the existence of topologically locally flat spheres realizing a configuration, and show for instance that the combinatorial configuration corresponding to the projective plane over any finite field is not realized. Such obstructions are used to show that a particular contact structure on certain graph manifolds is not (strongly) symplectically fillable. We also show that a configuration of real pseudolines can be complexified to give a configuration of smooth, indeed symplectically embedded, 2-spheres.
Afrofuturism
Authors: English Daylanne K.
Published: July 2017

Afrofuturism refers to a flourishing contemporary movement of African American, African, and Black diasporic writers, artists, musicians, and theorists. Afrofuturism comprises cultural production and scholarly thought—literature, visual art, photography, film, multimedia art, performance art, music, and theory—that imagines greater justice and a freer expression of Black subjectivity in the future, or in alternative places, times, or realities. It also offers speculation about a world wherein black people are normative. Afrofuturism can also imagine dystopic worlds to come, with contemporary injustices projected into, and often intensified in, the future. However, Afrofuturist works do not always look to the future but, rather, often unsettle notions of linear time. More broadly defined, Afrofuturism reimagines not only new forms of temporality, but also new Black experiences and identities via science and speculative fiction or other artistic and intellectual means. It often does so by exploring both the potential and the pitfalls of technoculture and posthumanism. Although the movement has certainly exploded in recent years, especially since 2000, its intellectual and aesthetic underpinnings can be traced back to mid- and late-19th century African American novels that imagined alternative realities and communities for Black people in the contexts of enslavement and then racial oppression of the Post-Reconstruction era. Such historic imaginings find their counterpart in current Afrofuturist work that addresses the fallout from the 2016 US presidential election, the COVID-19 pandemic, and global uprisings against police violence and white supremacy. In these contemporary contexts, Afrofuturism offers a robust intellectual, political, and artistic framework for critique and resistance, and for the representation of a more just world, one that centers and values Black people and their well-being.
Intersectionality and Education
Authors: Grant Carl , Zwier Elisabeth
Published: July 2017

Intersectionality theories, intersectionally informed methodologies, and intersectional praxis seek to explain, critique, and transform relationships of oppression and privilege among individuals, groups, and institutions. These shifting power relationships are co-constructed through identity categories and justified by symbolic representations. Given the plurality of intersectional theories, no one definition can encompass the diverse strands of scholarship that make up this arena. However, Winker and Degele 2011 proposes a useful multilevel analytical approach that traces how intersectional privilege and oppression are created, maintained, and contested (see also Analytical Frameworks). The researchers’ framework is key to understanding the organization of this article around three concepts: identity constructions (how difference is made and unmade between the self and others), symbolic representations (norms, ideologies, images), and social structures (class, gender, race, and body), with their accompanying power relations (classisms, heteronormativisms, racisms, and bodyisms) (see also Winker and Degele 2011). Work using intersectionality theories in the field of education may be focused on microlevel phenomena, such as individual identity development and interpersonal relationships; meso-level phenomena, in the case of school policies and practices that respond to intersectional identities; or macro-level phenomena, like educational funding schemes that produce intersectional privilege or oppression for particular groups. Scholarly work in the field of education that predates the use of the term “intersectionality” speaks of human relations, interactions, integration, and bridging perspectives (see also Intersectionality’s Early Expressions in Education). Scholars and educators in the cross-disciplinary field of intersectionality and education draw on research about individual and group experiences within schools and universities, as well as the scholarship, activism, and policy work of black feminist theorists and sociologists (see also Intersectionality’s Development in Feminist Theory and Praxis). Intersectional research in education has kept a dual focus on theory and practice, though the latter tends to have primacy given the discipline’s applied nature (see also K–12 Education, Teacher Education, Higher Education, Comparative and International Education, Educational Policy).
Cognitive Consistency Theories
Authors: Russo J. Edward , Chaxel Anne-Sophie
Published: July 2017

Cognitive consistency is the agreement, coherence, or fit among related beliefs. It is a fundamental topic in psychology research, with a long history that has recently returned to prominence. Over almost a century, cognitive consistency has played an active role in research, if sometimes under such other labels as coherence, compatibility, congruence, balance, and consonance (although usually its negative, dissonance). The diversity of labels was compounded by a dispersal of interest across several subareas of psychology and across multiple domains of application. If the phenomenon of cognitive consistency has received multiple labels, all the paradigms that we review are united by a core overall objective: to understand how, why, and when human beliefs are influenced by a desire for consistency. The goal of understanding cognitive consistency has led researchers to employ methods not previously used or not available until recently, such as those of neuroscience. We conclude our bibliography by considering the question of the rationality of cognitive consistency, an issue that has received considerable attention but whose complexity remains largely unresolved and actively debated.
Mechanical Modeling of a Keratoconic Cornea
Authors: Perone Jean Marc , Conart Jean Baptiste , Bertaux Pierre-Jean , Sujet-Perone Nicolas , Ouamara Nadia , Sot Maxime , Henry Jean Jacques
Published: July 2017

Purpose:

We created a laboratory model of a cornea that was subjected to various pressures and thermal and mechanical factors to better understand the genesis of keratoconus deformation.

Methods:

A steel base allowed for fixation of circular multilaminated patches of araldite (10 cm in diameter, 5 mm thick) in which the corneal anatomy was modeled. The model was plunged into a steam room (374°F/3 bars of pressure for 1 h) to ensure thermal homogeneity and was subjected to pressure using compressed air. Three models were assessed: a fault-free model with no lesion (model 1), and 2 models with a defect. The first of the defective models (model 2) had an external crack-type lesion (1 cm long; 1 mm deep). The second defective model (model 3) had one quarter thinned down using abrasive sandpaper (thickness reduced by 30%–40%).

Results:

For model 1, which represented a healthy cornea, homogeneous modification was noted when examined under polarized light. In model 2, no excessive deformation was noticed, but there were stress lines at the edge of the lesion. Model 3 had a deformity, similar to keratoconic deformation.

Conclusions:

Our findings suggest that the disease progresses under environmental stresses, but only when there is an initial defect, and especially when there is a thinning down defect. This thinning down defect may be induced by continual eye rubbing.
SLC5A1 Mutations in Saudi Arabian Patients With Congenital Glucose‐Galactose Malabsorption
Authors: Al‐Suyufi Yasir , ALSaleem Khalid , Al‐Mehaidib Ali , Banemai Mohammed , Aldekhail Wajeeh M. , Al‐Muhandes Abdulhakim , Mohammed Manal , Allam Rabab , Jambi Amani , Ramzan Khushnooda , Imtiaz Faiqa
Published: July 2017

Congenital glucose‐galactose malabsorption (cGGM) is a rare autosomal recessive disorder, caused by mutations in the SLC5A1 gene, encoding the sodium/glucose cotransporter 1, which may result in severe life‐threatening osmotic diarrhea due to the accumulation of unabsorbed sugars in the intestinal lumen. If treated early with elimination of glucose and galactose from the diet, patients usually recover and develop normally. We present clinical and molecular data from 16 unrelated cGGM diagnosed Saudi patients from consanguineous families with majority of them having previous positive family history of cGGM. Sanger sequencing for the full coding regions of SLC5A1 for all patients resulted in the identification of 4 allelic variants in a homozygous state. Two mutations are novel; c.265G>A (p.G89R) and c.1304 G>A (p.G435D), and 2 have been previously reported to cause cGGM, c.765 C>G (p.C255W) and c.1136 G>A (p.R379Q). This is the first report delineating the clinical and molecular basis of cGGM in patients from this region.
The Relationship Between Child Mortality Rates and Prevalence of Celiac Disease
Authors: Biagi Federico , Raiteri Alberto , Schiepatti Annalisa , Klersy Catherine , Corazza Gino R.
Published: July 2017

Objectives:

Some evidence suggests that prevalence of celiac disease in the general population is increasing over time. Because the prognosis of celiac disease was a dismal one before discovering the role of gluten, our aim was to investigate a possible relationship between children under‐5 mortality rates and prevalence rates of celiac disease.

Methods:

Thanks to a literature review, we found 27 studies performed in 17 different countries describing the prevalence of celiac disease in schoolchildren; between 1995 and 2011, 4 studies were performed in Italy. A meta‐analysis of prevalence rates was performed. Prevalence was compared between specific country under‐5 mortality groups, publication year, and age.

Results:

In the last decades, under‐5 mortality rates have been decreasing all over the world. This reduction is paralleled by an increase of the prevalence of celiac disease. The Spearman correlation coefficient was −63%, 95% confidence interval −82% to −33% (P < 0.001). So, the higher the mortality rate, the lower the prevalence of CD. This finding is confirmed by the meta‐analysis of the 4 studies conducted in Italy over time.

Conclusions:

The under‐5 mortality rate seems to influence the prevalence of celiac disease in the general population. In the near future, the number of patients with celiac disease will increase, thanks to the better environmental conditions that nowadays allow a better survival of children with celiac disease.
Lutein and Cognition Across the Lifespan
Authors: Mohn Emily S. , Johnson Elizabeth J.
Published: July 2017

Epidemiological studies suggest that consumption of lutein-rich foods may be of benefit in promoting cognitive health. Among the carotenoids, lutein and it isomer, zeaxanthin, are the only 2 that cross the blood-retina barrier to form macular pigment (MP) in the retina. Lutein also preferentially accumulates in the human brain across multiple life stages. Lutein concentrations in the retina of both human and nonhuman primates are significantly correlated with their levels in matched brain tissues, allowing for the use of MP density, which can be measured noninvasively in humans, as a biomarker of lutein in the brain. This has important implications for intervention studies involving lutein given that MP density, such as brain lutein, has been reported to be significantly related to cognitive function in adults. Although less is known about infants, cross-sectional studies have shown that breast milk lutein content enriches lutein in brain tissue and is related to infant recognition memory scores. Intervention studies in adults indicate that lutein may positively affect cognitive performance, and this effect may be influenced by the omega-3 fatty acid, docosahexaenoic acid. Although lutein is not an essential nutrient, efforts may be warranted to establish age-specific recommended intakes for this dietary bioactive for promotion of cognitive health.
The Associations of Hospital Volume, Surgeon Volume, and Surgeon Experience with Complications and 30-Day Rehospitalization after Free Tissue Transfer: A National Population Study
Authors: Mahmoudi Elham , Lu Yiwen , Chang Shu-Chen , Lin Chia-Yu , Wang Yi-Chun , Chang Chee Jen , Cheng Ming-Huei , Chung Kevin C.
Published: July 2017

Background:

Greater provider volume is associated with better outcomes. There is, however, a paucity of evidence on volume-outcome associations for surgical complications and 30-day all-cause rehospitalization after free tissue transfer or free flap surgery. Surgical complications and frequent rehospitalization are important quality indicators that substantially hinder appropriate health care spending. The authors hypothesized that increased provider volume and surgeon experience are associated with lower complication and hospital readmission rates.

Methods:

The authors conducted a retrospective cohort study of adults aged 18 to 64 years who underwent free tissue transfer. They examined 100 percent of all free tissue transfers between 2001 and 2012 using Taiwan’s national data, and used regression modeling to examine associations between volume and outcome. All models were adjusted for patient, surgeon, and hospital characteristics.

Results:

Seventeen percent of free tissue transfer operations (4201 of 25,327) had complications. Infection was the most prevalent after free tissue transfer (70 percent), and the 30-day rehospitalization rate was approximately 20 percent. Hospital volume was associated with a small decrease in complications (OR, 0.99; 95 percent CI, 0.99 to 0.99; p < 0.01). For surgeons, years of experience and not annual case volume decreased surgical complications (OR, 0.98; 95 percent CI, 0.97 to 0.99; p = 0.01). The authors did not find any association between hospital or surgeon volume, or surgeon’s years of experience and 30-day rehospitalization.

Conclusions:

Higher-volume hospitals and more experienced surgeons were shown to have a lower likelihood of postsurgery complications. Hospital process and structure affect outcomes and reduce surgical complications. Reducing 30-day rehospitalization may require payment reform, as it demands coordinated care before and after hospital discharge.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
TLR4 Inactivation in Myeloid Cells Accelerates Bone Healing of a Calvarial Defect Model in Mice
Authors: Wang Dan , Gilbert James R. , Taylor Gwen M. , Sodhi Chhinder P. , Hackam David J. , Losee Joseph E. , Billiar Timothy R. , Cooper Gregory M.
Published: July 2017

Background:

Toll-like receptor 4 (TLR4) has been implicated in inflammation-induced bone destruction in various chronic bone diseases; however, its direct influence on bone healing is not well understood. The authors’ previous study showed accelerated bone healing with higher osteoclastogenesis gene expression in toll-like receptor 4 knockout mice (TLR4-/-). This study aimed to further elucidate the underlying cellular mechanisms during fracture healing by generating a myeloid cell-specific toll-like receptor 4 knockout model (Lyz-TLR4-/- mice).

Methods:

Calvarial defects, 1.8 mm in diameter, were created in wild-type, TLR4-/-, and Lyz-TLR4-/- mice. Bone healing was investigated using micro–computed tomography and histologic, histomorphometric, and immunohistochemistry analyses. Primary bone marrow–derived cells were also isolated from wild-type, TLR4-/-, and Lyz-TLR4-/- mice to measure their osteoclast differentiation and resorption properties.

Results:

A similar faster bone healing response, with active intramembranous bone formation, intense osteopontin staining, and more osteoblast infiltration, was observed in TLR4-/- and Lyz-TLR4-/- mice. Tartrate-resistant acid phosphatase staining showed more osteoclast infiltration in Lyz-TLR4-/- mice than in wild-type mice at day 7. Primary bone marrow–derived cells isolated from TLR4-/- and Lyz-TLR4-/- mice presented enhanced osteoclastogenesis and resorption activity compared with those from wild-type mice. Comparable M0, M1, and M2 macrophage infiltration was found among all groups at days 1, 4, and 7.

Conclusions:

This study revealed that inactivation of toll-like receptor 4 in myeloid cells enhanced osteoclastogenesis and accelerated healing response during skull repair. Together with the role of toll-like receptor 4 in inflammation-mediated bone destruction, it suggests that toll-like receptor 4 might regulate inflammation-induced osteoclastogenesis under different clinical settings.
Facial Nerve Supply to the Orbicularis Oculi around the Lower Eyelid: Anatomy and Its Clinical Implications
Authors: Choi Yeop , Kang Hyun Gu , Nam Yong Seok , Kang Jae-Goo , Kim In-Beom
Published: July 2017

Background:

The motor innervation of the lower orbicularis oculi has not been clearly established. There is a discrepancy between anatomical descriptions and clinical outcomes of the motor innervation of the pretarsal orbicularis oculi muscle. Therefore, the purposes of this study were to identify every motor and sensory nerve of the lower eyelid, and to reveal the detailed motor nerve pathways toward the medial canthal area.

Methods:

Fresh cadaver dissections were performed on 50 hemifaces under a surgical microscope. Submuscular and intramuscular nerves of the lower eyelid were identified, and the pathways of facial nerves that ran toward the medial canthus were traced.

Results:

Vertical submuscular nerves at the lower eyelid originated from the infraorbital foramen, indicating that all were sensory nerves. The zygomatic branch of the facial nerve traveled obliquely through the anterior cheek and supplied the orbicularis oculi of the lower eyelid and the medial portion of the upper eyelid. Its route was defined as a clinically useful line, the medial orbicularis motor line. In addition, the nerve innervating the pretarsal orbicularis oculi arose at the superomedial preseptal area and extended horizontally and laterally. Interestingly, the angular nerve appeared not to innervate the palpebral orbicularis oculi.

Conclusions:

In the lower eyelid, the vertical sensory and the oblique motor nerve supplies are independent and clearly distinguished in aspect of their own routes. The medial orbicularis motor line represents the motor route to the medial portion of the orbicularis oculi. These results might provide valuable knowledge about surgical anatomy for safe lower blepharoplasty with or without midface lift.
Synthetic single domain antibodies for the conformational trapping of membrane proteins
Authors: Zimmermann Iwan , Egloff Pascal , Hutter Cedric A. , Stohler Peter , Bocquet Nicolas , Hug Melanie , Siegrist Martin , Svacha Lisa , Gera Jennifer , Gmür Samira , Spies Peter , Gygax Daniel , Geertsma Eric R. , Dawson Roger J.P. , Seeger Markus A.
Published: July 2017

Single domain antibodies called nanobodies are excellent affinity reagents for membrane proteins. However, their generation relies on immunizations, which is only amenable to robust proteins and impedes selections in the presence of non-covalent or toxic ligands. To overcome these key limitations, we developed a novelin vitroselection platform, which builds on synthetic nanobodies called sybodies. Inspired by the shape diversity of natural nanobodies, three sybody libraries exhibiting different randomized surface shapes were engineered for high thermal stability. Using ribosome display, exceptionally large libraries were pre-enriched against membrane protein targets and subsequently funneled into a robust phage display process, thereby reducing selection bias. We successfully generated conformation-selective, high affinity sybodies against the human glycine transporter GlyT1, the human equilibrative nucleotide transporter ENT1 and a bacterial ABC transporter. Our platform builds exclusively on commercially available reagents and enables non-specialized labs to generate conformation-specific binders against previously intractable protein targets.
Causal Associations Between Body Mass Index and Mental Health: A Mendelian Randomization Study
Authors: van den Broek Nina , Treur Jorien L. , Larsen Junilla K. , Verhagen Maaike , Verweij Karin J. H. , Vink Jacqueline M.
Published: July 2017

Background

Body Mass Index (BMI) is negatively correlated with subjective well-being and positively correlated with depressive symptoms. Whether these associations reflect causal effects or confounding is unclear.

Methods

We examined causal effects between BMI and subjective well-being/depressive symptoms with bi-directional, two-sample Mendelian randomization using summary-level data from large genome-wide association studies. Genetic variants robustly related to the exposure variable acted as instrumental variable (two thresholds were used;p<5e-08 andp<1e-05). These ‘instruments’ were then associated with the outcome variable. Pleiotropy was corrected for by two sensitivity analyses.

Results

Substantial evidence was found for a causal effect of BMI on mental health, such that a higher BMI decreased subjective well-being and increased depressive symptoms. No consistent evidence was found for causality in the other direction.

Conclusions

This study provides support for a higher BMI causing poorer mental health. Further research should corroborate these findings and consider non-linear effects and sex differences.
Rapid evolution of female-biased genes among four species of Anopheles malaria mosquitoes
Authors: Papa Francesco , Windbichler Nikolai , Waterhouse Robert M. , Cagnetti Alessia , D'Amato Rocco , Persampieri Tania , Lawniczak Mara K.N. , Nolan Tony , Papathanos Philippos Aris
Published: July 2017

Understanding how phenotypic differences between males and females arise from the sex-biased expression of nearly identical genomes can reveal important insights into the biology and evolution of a species. Among Anopheles mosquito species, these phenotypic differences include vectorial capacity, as it is only females that blood feed and thus transmit human malaria. Here, we use RNA-seq data from multiple tissues of four vector species spanning the Anopheles phylogeny to explore the genomic and evolutionary properties of sex-biased genes. We find that, in these mosquitoes, in contrast to what has been found in many other organisms, female-biased genes are more rapidly evolving in sequence, expression, and genic turnover than male-biased genes. Our results suggest that this atypical pattern may be due to the combination of sex-specific life history challenges encountered by females, such as blood feeding. Furthermore, female propensity to mate only once in nature in male swarms likely diminishes sexual selection of post-reproductive traits related to sperm competition among males. We also develop a comparative framework to systematically explore tissue- and sex-specific splicing to document its conservation throughout the genus and identify a set of candidate genes for future functional analyses of sex-specific isoform usage. Finally, our data reveal that the deficit of male-biased genes on the X Chromosomes in Anopheles is a conserved feature in this genus and can be directly attributed to chromosome-wide transcriptional regulation that de-masculinizes the X in male reproductive tissues.
Communication apprehension and students’ educational choices
Authors: Arquero Jose Luis , Fernández-Polvillo Carmen , Valladares-García Dolores
Published: July 2017

Purpose

The literature evidences the effects of communication apprehension (CA), defined as the level of fear and anxiety associated with either real or anticipated communication, on educational efforts and suggests that (via the perceived desirability of certain professions) it could affect vocational choices. The purpose of this paper is to investigate the link between CA and the vocational choice of secondary education students.

Design/methodology/approach

Data were obtained from two sources: a self-administered questionnaire to measure the students’ CA levels and their academic preferences, and the vocational counsellors’ advice for these students.

Findings

The results confirm the existence of a link between CA and both students’ vocational choices and counsellors’ advice. In general terms, apprehensive students tend to choose vocational education, whereas students with lower levels prefer university for further education. Focussing on the later, more apprehensive students tend to choose science degrees, which are perceived as requiring lower levels of communication skills.

Research limitations/implications

Limitations include the use of a convenience sample in only a country.

Practical implications

Apprehensive students could be avoiding a path, with all the implications for their professional future, because it is perceived as frightening due to the apparent communication level required. As the literature note the links between CA and communication self-efficacy allows the development of educational interventions resulting in a reduction of CA.

Originality/value

The scarce early literature has paid attention to occupational and educational choices in higher and further education, but there is no research focussing on the link between CA and pre-university academic decisions.
Rethinking resilience planning: from problems to potential
Authors: Novak Vera M. , Fernandez-Anez Nieves , Shiraishi Koichiro
Published: July 2017

Purpose

Planning for the future can become mired in fixing the problems of the present. To create alternative solutions, planning must break free of the boundaries and assumptions of existing paradigms. The purpose of this paper is to explore an alternative way of thinking that reframes the issues from problems of “what is” to the potential of “what could be” in the context of socio-ecological resilience.

Design/methodology/approach

A case study reviews the limitations revealed during a traditional problem-solving exercise on the topic of Coastal Eco-Cities, as well as the innovations resulting from the rethinking of the issues through the lens of the alternative paradigm.

Findings

A key finding is the significance of linguistic modality, shifting from objective expressions to subjective dialogue.

Originality/value

The originality of this approach is the emphasis on the framing of the problem before the development of the solution and the methodological implications of this early dialogue.
The dominant influence of logistics capabilities on integration
Authors: Mandal Santanu , Bhattacharya Sourabh , Korasiga Venkateswara Rao , Sarathy Rathin
Published: July 2017

Purpose

Using dynamic capabilities theory, this paper aims to posit logistics capabilities (namely information, demand, supply, cooperation and coordination) when integrated at the supply chain level gives rise to supply chain resilience. The current investigation explores further on the inter-relationship among dominant logistics capabilities and integrated logistics capabilities.

Design/methodology/approach

To test the proposed hypotheses, data were gathered from 339 supply chain professionals and were evaluated through structural equation modeling. The measures were pretested through exploratory factor analysis and confirmatory factor analysis and then measures were deployed for final testing.

Findings

Findings suggest that logistics capabilities do exert a strong influence on supply chain resilience through effective logistics integration. Further, these logistics capabilities do share certain inter-relationships among themselves. Supply chain resilience does have positive performance implications. The authors also tested for moderation of cooperation and coordination and proposed an alternate model which found support in post hoc testing.

Originality/value

The study holds immense value for practitioners and managers, as they undersigned that logistics capabilities need to be integrated at the supply chain level for developing overall supply chain resilience. Further, it underscored how the inter-relationship among the individual logistics capabilities varies in the development of supply chain resilience.
Towards developing robust climate risk management strategies in the estuarine park of the Swan River, Western Australia
Authors: Allender Clare , Sutrisna Monty , Zaman Atiq Uz
Published: July 2017

Purpose

This study aims to support the development risk management strategies towards improving the resilience of assets located in the estuary and lower level of the Swan River, Western Australia. The study evaluated the key role of Federal/State policies in adaptation planning and the communication and interface between various stakeholders, including State/Local governments, construction professionals, property developers and landowners.

Design/methodology/approach

The study applied a mixed research approach through a questionnaire survey followed by an in-depth interview involving local construction experts. Collected data were analysed following the grounded theory methodology style of data analysis.

Findings

The findings revealed a convoluted understanding of communication networks and responsibility for owning the future risks between relevant stakeholders. As a result, a framework illustrating clear process and roles in mitigating risk and implementing adaptive asset management measures has been formulated and presented in this study.

Originality/value

Scientific evidence suggested that sea-level rise and increased frequency of major coastal flooding events are inevitable as early as 2100, and having a comprehensive risk management plan of assets to anticipate climate risks and to improve urban resilience is essential. The proposed framework is aimed at local stakeholders in improving current state of communication and adaptation planning as a pathway to develop a robust risk management strategy.
Re-visiting the renewable energy–economic growth nexus
Authors: Alabi Oluwafisayo , Ackah Ishmael , Lartey Abraham
Published: July 2017

Purpose

This paper aims to investigate the dynamic relationship between renewable energy and economic growth in African OPEC member countries (Angola, Algeria and Nigeria).

Design/methodology/approach

The fully modified ordinary least squares technique for heterogeneous cointegrated panels (Pedroni, 2000) is used to estimate the parameters of the model.

Findings

The study revealed four main findings. First, there is a bidirectional causality between renewable energy and economic growth in the long and the short run. Second, a bidirectional causality exists between non-renewable energy and economic growth in the short and long run. Third, a bidirectional causality exists between CO2 emissions and economic growth. Fourth, a unidirectional causality was also found between CO2 emissions and non-renewable energy consumption with the direction of causality stemming from the consumption of non-renewable energy to CO2 emissions.

Practical implications

Because renewable consumption enhances growth, OPEC-member Africa countries should encourage investment in modern renewable sources that has high conversion efficiency such as solar, wind and hydro to strengthen their response to mitigating the impacts of climate change.

Originality/value

This study applies multiple methods to analyze the relationship between renewable energy and economic growth in African OPEC countries.
Development of a nanodiamond-based lubricant for a versatile use in the beverage industry conveyor systems
Authors: Torres-Sanchez Carmen , Balodimos Nikolaos
Published: July 2017

Purpose

The purpose of this paper is to propose a nanodiamond-particle-loaded food-grade lubricating oil, a nanolubricant, that can be used over a broad range of loads in factories (low load applications like conveyor systems and high load applications like heavy machinery).

Design/methodology/approach

Tribological performance of the nanolubricant was studied at both load levels. A typical factory-sized conveyor belt used for beverage packaging (aluminium cans, glass and PET bottles) was employed for the low load range. Coefficients of friction and wear scars were measured and the lubricating performance was quantified. A four-ball tester was used to characterise the performance of the nanolubricant as per ASTM D2783/D4172. A comparison between the nanolubricant and baseline oils was carried out.

Findings

Results show an overall decrease in the coefficients of friction and wear scars for all packages at low pressures when the nanolubricant is used. They also show a better friction-reduction performance in the high load regimes. The results indicate that the nanolubricant is versatile in both ranges of loading.

Practical implications

The current protocols for lubrication in the food and drink factories involve the use of water-based detergents for the conveyor lines and industry-grade oils for the machinery. The use of a single and versatile lubricant for both ranges of loads may have a positive impact on the sustainability and environmental performance of the sector.

Originality/value

Beverage processing and packing factories need their mechanised conveyor systems suitably lubricated to avoid excessive friction between the containers and the load-bearing surface of the conveyors (e.g. belts or chains). Other areas of the conveying systems, such as motors, gears, rollers and bearings, also need suitable lubrication to prevent failure and lengthen their operating life. There is a myriad of lubricants and lubricating solutions for each of these areas independently, but there is no commercial lubricating fluid that could be used on both successfully.
Friction and wear behaviour of Fe-Cu-C based self lubricating material with CaF2as solid lubricant
Authors: Sharma Sanjay Mohan , Anand Ankush
Published: July 2017

Purpose

This paper aims to investigate the effect of CaF2(calcium fluoride) addition as a solid lubricant on the friction and wear behaviour of sintered Fe-Cu-C materials under different loads.

Design/methodology/approach

In this study, the effects of CaF2added in varying weight percentages on the friction-wear properties of Fe-2Cu-0.8C alloys are investigated. Five Fe-2Cu-0.8C-based compositions comprising CaF2in 0, 3, 6, 9 and 12 Wt.% were prepared using the single-stage compaction and sintering technique. Friction coefficient, wear loss, hardness and compressive strength of the specimens were measured. The worn-out surfaces were analysed using a scanning electron microscope. Friction and wear tests were carried out on pin-on-disc machine under dry sliding conditions at room temperature.

Findings

The alloy with 3 Wt.% CaF2was found to be useful in improving wear and friction properties, whereas higher contents of CaF2resulted in increased wear and friction. Apart from enhanced tribological properties, a slight decrease in the compressive strength was also observed in the 3-Wt.%-CaF2-added sample. Adhesion and abrasion were the prominent wear types observed during this study.

Originality/value

A new self-lubricating composite is developed where CaF2is used as a solid lubricant in a Fe-Cu-C-based matrix. CaF2, being a high-temperature lubricant, is tried and tested for friction and wear at room temperature, and the results show that the addition of CaF2in Fe-Cu-C improved its friction and wear properties. Thus, the developed material can be used for antifriction applications.
Influence of surface roughness and ZDDP additive on the friction and wear of reciprocating sliding surfaces at high contact pressures
Authors: P.M. Anil , Rajamohan Vasudevan
Published: July 2017

Purpose

Surface roughness has been proved to be influencing the running-in wear of machined components under dry and lubricated sliding conditions. Zinc dialkyl dithiophosphate (ZDDP) is widely used as an anti-wear additive, which reduces the wear by the formation of a tribofilm on the surface (Spikes, 2004). Factors such as temperature, sliding distance, etc. influence the formation of the film. A significant reduction in the power loss due to friction and wear is possible if a synergy is attained between surface roughness effects and the effectiveness of the tribofilm. The present work aims to study the influence of surface roughness and ZDDP addition on the formation and removal of the tribofilm under high contact pressures.

Design/methodology/approach

Samples were prepared by machining. Surface roughness was varied by varying the milling parameters. A reciprocating friction and wear test machine with a ball-on-flat geometry was used for the study. Tests were performed with mineral base oil and base oil added with 1 per cent by weight ZDDP under different operating parameters. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) with energy dispersive X-Ray spectroscopy (EDS) analysis were conducted to study the surface morphology of the tribofilm.

Findings

A quasi-steady-state analysis conducted showed that the wear rate was much lower when tested with base oil containing ZDDP after about 65 min. AFM analysis confirmed the presence of chemically reacted films on the surface. SEM analysis revealed agglomeration of crystal like glassy phosphates. However, high contact pressures at the interface caused the removal of the films resulting in variations in the coefficient of friction. A comparison of the wear rates among the samples of different roughness values tested at 100°C showed that the anti-wear performance of ZDDP was not effective due to high contact pressures.

Originality/value

The findings in this study regarding the tribofilm formation with ZDDP additive and its failure due to high contact pressures will be beneficial for further investigation on wear resistant boundary films developed under such extreme conditions.
The tribological performance of brucite lubricant at high temperature
Authors: Hu Xueping , Tang Pengfei , Wang Yanfei , Liu Jing
Published: July 2017

Purpose

Water-based graphite lubricants have good lubricity in the process of metal forming, especially for hot-rolling seamless pipe. Although the use of water as a working fluid system instead of conventional mineral oil has many advantages for the fuel consumption, post cleaning and a new type of lubricant, the graphite contaminated the machine and workers for its physical properties. From the global environmental protection viewpoint, it is urgent to develop a kind of benign material.

Design/methodology/approach

Magnesium hydroxide which has the average particle size of 10 μm was chosen as a base material without further modification and pretreatments. On the HT-1000 high-temperature tribometer, the influence of temperature and lubricant materials on the friction coefficient was studied. The tribological performance at 900°C provided evidence under high temperature for exploring a new lubricant material.

Findings

Tap water-based brucite lubricant will open a new chapter in the industrial lubrication, effectively avoiding many unfavorable factors caused by graphite lubrication, such as conductivity, pollution and energy loss. Meanwhile, it expanded the application of brucite as flame-retardant agent, catalyst, water treatment agent and so on.

Originality/value

It is a new and environmental lubricant to tap water-based brucite lubricant. And specially, the preparation process of lubricant is simple and economical.
Effects of structural parameters of oil groove on transmission characteristics of hydro-viscous clutch based on viscosity-temperature property of oil film
Authors: Xie Fangwei , Wu Diancheng , Tong Yaowen , Zhang Bing , Zhu Jie
Published: July 2017

Purpose

The purpose of this paper is to study the influence of structural parameters of oil groove (such as central angle number, depth and so on) on pressure, flow, load capacity and transmitted torque between friction pairs of hydro-viscous clutch.

Design/methodology/approach

According to the working process of friction pairs of hydro-viscous clutch, mathematical models of hydrodynamic load capacity and torque transmitted by the oil film were built based on viscosity-temperature property. Then analytical solutions of pressure, flow, load capacity and transmitted torque were obtained; effects of central angle of oil groove zone and friction contact zone, oil film thickness, number of oil grooves on pressure, flow, load capacity and torque were studied theoretically.

Findings

The research found that the central angle of oil groove zone, number of oil grooves and oil groove depth have similar effects on flow, which means that with the increase of central angle, number or depth of oil grooves, the flow also increases; pressure in friction contact zone and oil groove zone drops along radial direction, whereas its value in oil groove zone is higher. With the increase of the central angle of oil groove zone, pressure in friction contact zone and friction contact zone rises, and the load capacity increases, whereas the transmitted torque drops. Number of oil grooves has little effect on load capacity. When the oil film thickness increases, its flow increases accordingly, whereas the pressure, load capacity and transmitted torque drops. Meanwhile, the transmitted torque decreases with the increase of number of oil grooves, whereas the oil groove depth nearly has no effects on transmitted torque.

Originality/value

In this paper, mathematical models of hydrodynamic load capacity and torque transmitted by oil film were built based on viscosity-temperature property in the working process of hydro-viscous clutch, and their analytical solutions were obtained; effects of structural parameters of oil groove on transmission characteristics of hydro-viscous clutch based on viscosity-temperature property were revealed. The research results are of great value to the theory development of hydro-viscous drive technology, the design of high-power hydro-viscous clutch and relative control strategy.
Different strokes for different folks: scaling a blended model of teacher professional learning
Authors: Butler Deirdre , Leahy Margaret , Hallissy Michael , Brown Mark
Published: July 2017

Purpose

The purpose of this paper is to describe an innovative model of teacher professional learning that has evolved over a decade (2006 to 2016).

Design/methodology/approach

Working in a range of different school contexts, in conjunction with an ongoing engagement with the research literature, has enabled the development over three phases of a robust yet flexible framework that meets teachers’ expressed needs. At the same time, the framework helps to shift teachers’ pedagogical orientations, as the learning design supports school-focused, job-embedded teacher professional learning, which challenges more traditional instructional environments by infusing digital technologies and other elements of twenty-first century skills into teaching and learning.

Findings

Building on the experiences of the first two phases, the paper reports the most recent phase which expands on the emergence of a fourth wave of online learning to design and develop a massive open online course (MOOC) that potentially enables the massive scaling up of access to this already validated model of teacher professional development. The importance of maintaining key elements, threshold concepts and signature pedagogies in the design of MOOCs for teacher professional learning are discussed, and the paper concludes with early lessons from this latest work in progress.

Originality/value

Challenges are identified relating to the design of the social supports within the MOOC structure to sustain the collaboration, dialogue and ongoing reflection observed across Phases 1 and 2 that are necessary for the changes in pedagogical orientation and classroom practices.
Preventing isolation in sheltered housing: challenges in an era of reduced support funding
Authors: Gray Anne M.
Published: July 2017

Purpose

The purpose of this paper is to inform the policies of sheltered housing providers with regard to preventing isolation amongst residents and generating practical support between them, particularly in the current period of reduced funding for housing support.

Design/methodology/approach

The paper reports a postal survey of 120 residents across eight estates, focus groups on these and eight other estates and survey responses from 326 estate managers.

Findings

Childless residents are especially vulnerable to lack of support, depending on friends or on paid care. Those estates with a rich array of organised social activities generated more support and friendships amongst neighbours than those with few activities. Managers perform an important service in generating and supporting social activities, but their role is diminishing and restricted by short hours on site. Residents’ groups need capacity-building support to organise more by themselves. Cross-generational contacts are particularly valuable but residents need help to access them outside of their own families.

Research limitations/implications

Certain forms of group activity which are the most valuable in terms of promoting mental stimulation and exercise are rarely organised by residents’ groups without staff support.

Originality/value

How to generate mutual aid between residents is an important objective for housing providers in a period of reduced funding for staff time and of severe constraints on social care budgets.