bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of fiber‐reinforced recycled polyamide in single stage and two stage injection molding
Authors: Wellekötter Jochen , Christian Bonten
Published: July 2018

Climate change and a growing energy demand drive the development of lightweight construction in the automotive industry. The recent focus of interest is on glass and carbon fiber‐reinforced plastics. A resulting increase of production waste and scrap parts requires an efficient recycling. Although thermoplastics are generally suitable for reprocessing, recycled polyamides like PA6 show differing mechanical properties in comparison to virgin material due to molecular degradation processes. To achieve a high recycling rate and to compensate for the reduced mechanical properties, the parts of the test series of this study are filled with glass fibers (20 and 30 wt%). To increase the mechanical properties even further, a single‐stage injection molding compounder is used. A comparison with the standard, two‐stage production process provides further understanding of the complex interactions. The study is carried out with various blends of recycled and virgin PA6 with a recycling rate of 0, 25, 50, and 75%. Both single and double recycled PA6 are used. For the evaluation of the mechanical properties, tensile tests, bending tests and impact bending tests are conducted and assessed by fibers length, fiber–matrix adhesion, and fiber content. The results of all tested recycling ratios show no direct influence of the recycling‐related impairment of the plastic on tensile strength, tensile modulus, bending strength, and impact resistance. Rather, the investigations indicate an expected direct relationship to the fiber content, whereby an increase in fiber content relates to a significant improvement of the mechanical properties. Furthermore, the investigated fiber length distributions show a correlation with the mechanical properties. Therefore, the more gentle material processing of the injection‐molding compounder and an associated reduction in fiber shortening, result in a superiority to the two‐stage production process. POLYM. COMPOS., 40:1731–1739, 2019. © 2018 Society of Plastics Engineers
Thermomechanical characterization of thermoplastic polyimides containing 4,4'‐methylenebis(2,6‐dimethylaniline) and polyetherdiamines
Authors: Rivera Nicholls Alejandro , Kull Ken , Cerrato Cole , Craft Garrett , Diry Jean‐Baptiste , Renoir Emilie , Perez Yesenia , Harmon Julie P.
Published: July 2018

In this work, we synthesized polyimides by incorporating an aromatic diamine monomer with a methylene linker, 4,4'‐methylenebis(2,6‐dimethylaniline) (MBDMA), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. We designed the polymers to exhibit thermal properties in between those of conventional aromatic polyimides and polymers with wholly aliphatic ether diamine links. Through dynamic mechanical analysis and differential scanning calorimetry, it is shown that control of the molar ratios of the aromatic MBDMA (4,4'‐methylenebis(2,6‐dimethylaniline)) and the composition and size of the aliphatic polyetherdiamine can be used to tune the glass transition. The polymers were characterized by GPC, FTIR, NMR, thermomechanical and calorimetric analysis, and microhardness testing. POLYM. ENG. SCI., 59:221–232, 2019. © 2018 Society of Plastics Engineers
A monitoring toolkit for banksia woodlands: comparison of different scale methods to measure recovery of vegetation after fire
Authors: Brundrett Mark , van Dongen Ricky , Huntley Bart , Tay Natasha , Longman Vanda
Published: July 2018

Here, we compare the efficiency and accuracy of remote sensing and plot‐based methods for measuring vegetation cover for the understory and canopy of banksia woodland in an urban area of Western Australia. Methods compared were visual estimation, foliage cover computation from photographs, satellite imagery and aerial photographs. Observations and images from 1 m2, 100 m2 and 625 m2 quadrats measured cover of small plants, understory plants and trees respectively. Aerial photography and satellite imagery allowed the number, height and cover of trees to be estimated in 625 m2 and 1 ha plots. The accuracy of methods was compared using a 28 month time series commencing before and after an intense bushfire that removed all foliage cover. Directly comparable methods were in close agreement and in combination allowed plant recovery to be quantified in great detail. Visual estimation of cover in the field was time‐consuming but necessary to measure the contribution of individual species. Visual estimates from 1 m2 downward photos allowed functional groups of plants to be measured. The number of green pixels selected manually in photographs confirmed that cover calculated from ground‐based photographs using algorithms was accurate, except when cover was very low. We developed a new algorithm for computing cover from photographs that was accurate at low cover (Gperc). Canopy cover estimation by algorithm from upward photographs was subject to more errors, requiring exclusion of some images. Landsat satellite images allowed the impacts of severe drought and previous fires to be identified against a background of relatively consistent seasonal variations since 1988. Aerial photographs from 1953 onwards showed gradual recolonisation by banksia woodland trees over 60 years following tree felling. These methods provide a toolkit for monitoring vegetation recovery after disturbance and baseline data for monitoring banksia woodland. This toolkit should also be suitable for most other plant communities.
Synthesis, Structural Determination, and Pharmacology of Putative Dinitroaniline Antimalarials
Authors: Casino Alessio del , Lukinović Valentina , Bhatt Rakesh , Randle Laura E. , Dascombe Michael J. , Fennell Dr Brian J. , Drew Michael G. B. , Bell Angus , Fielding Alistair J. , Ismail Fyaz M. D.
Published: July 2018

A series of novel, homologous compounds possessing the general formula N1‐Nn‐bis(2,6‐dinitro‐4‐trifluormethylphenyl)‐1,n‐diamino alkanes (where n=4, 6, 10 or 12), were designed to probe inter‐ and intra‐ binding site dimensions in malarial parasite (Plasmodium) tubulin. Various crystal structures, including chloralin and trifluralin, an isopropyl dimer, and 2,6‐dinitro‐4‐trifluoromethyl‐phenylamine, were determined. Dinitroanilines, when soluble, were evaluated both in culture and in vivo. Trifluralin was up to 2‐fold more active than chloralin against cultured parasites. The isopropyl dimer was water soluble (>5 mM) and revealed activity superior to that of chloralin in culture. The effects of selected dinitroanilines upon the mitotic microtubular structures of Plasmodium, the putative target of these dinitroanilines, were also determined. Electronic properties of the molecules were calculated using DFT (B3LYP/6‐31+G* level) to ascertain whether incorporation of such a pharmacophore could allow both QSAR and rational development of more selectively toxic antiparasitic agents.
Cluster Detection of Non‐Metallic Inclusions in 42CrMo4 Steel
Authors: Seleznev Mikhail , Wong Ka Yiu , Stoyan Dietrich , Weidner Anja , Biermann Horst
Published: July 2018

Recent progress in steel casting shows significant reduction of non‐metallic inclusions (NMIs). Unfortunately, total NMI volume reduction due to refining can surprisingly lead to NMI size enlargement or cluster formation. This effect decreases the fatigue endurance limit of steel, which is sensitive not only to the presence of large NMIs, but also to clusters of small inclusions, which are usually overlooked in standard metallography inspection. In the present paper, the authors aim to investigate clustering properties of NMIs in a dataset of 42CrMo4 steel, which are observed on fracture surfaces after fatigue tests and from inclusion patterns in polished cross‐sections after metallographic inspection. The authors use both data types for estimating critical distances as main cluster size parameters and find excellent agreement between the results of both methods. The clusters are determined by a classical statistical method of cluster analysis, called “agglomerative hierarchical clustering”. The authors show by means of methods of spatial point pattern analysis that their method yields clusters that are more plausible than clusters resulting from the well‐known Murakami “thumbnail rule”.
Rifaximin anti‐inflammatory activity on bovine endometrium primary cell cultures: a preliminary study
Authors: Flammini Lisa , Mantelli Leonardo , Volpe Alessandra , Domenichini Giuseppe , Di Lecce Rosanna , Dondi Maurizio , Cantoni Anna Maria , Barocelli Elisabetta , Quintavalla Fausto
Published: July 2018

Rifaximin is an unabsorbed oral antibiotic showing anti‐inflammatory properties in human pathologies like irritable bowel syndrome and inflammatory bowel disease. In veterinary medicine, rifaximin is primarily used in the treatment of dermatological diseases in all animal species, in therapy and prophylaxis of mastitis in cows and in the treatment of endometritis in cattle and horses. The aim of this preliminary study was to evaluate the anti‐inflammatory properties of rifaximin on primary cell cultures from bovine endometrium in which inflammatory response was induced by Lipopolysaccaride (LPS) treatment. Epithelial and stromal cells were isolated from bovine endometrium and separately incubated for 24 h with 1 μg mL−1 LPS after rifaximin (10, 50 and 100 μmol L−1) or dexamethasone (10 μmol L−1) pre‐treatment for 24 h. Supernatants were collected 24 h after LPS treatment and interleukin (IL)‐6 and IL‐8 accumulation was measured by ELISA. Rifaximin (10, 50 and 100 μmol L−1) dose dependently inhibited the LPS‐induced increase in IL‐6 and IL‐8 in stromal cells, whereas in epithelial cells it was not possible to detect any accumulation of these interleukins. Rifaximin reduced IL‐6 and IL‐8 production, showing a potential anti‐inflammatory effect that opens up to new possibilities for the use of this drug in uterine inflammatory diseases.
Evaluation of the effects of acetyl tributyl citrate as bio‐based plasticizer on the physical, thermal, and dynamical mechanical properties of poly(vinyl chloride)/polymethyl methacrylate blends
Authors: Aouachria Kamira , Massardier Valérie , Benaniba Mohamed Tahar , Belhaneche‐Bensemra Naima
Published: July 2018

This article details our work in studying the plasticization of Poly(vinyl chloride) (PVC)/Polymethyl methacrylate (PMMA) blends with bio‐based acetyl tributyl citrate (ATBC) in place of conventional plasticizers such as di(2‐ethylhexyl) phthalate. PMMA was blended with PVC in various ratios from 0 to 100 wt% by melt compounding with or without the plasticizer ATBC. Both the glass transition temperatures of the blends (differential scanning calorimetry) and Tα (dynamic mechanical thermal analysis) are consistent with a miscibility of the components, and Fourier transforms infrared spectroscopy studies show that there are specific interactions in the PVC/PMMA blends favoring the miscibility. The thermal degradation of the blends was studied by thermogravimetric analysis that shows the thermal degradation of rigid and plasticized PVC/PMMA is a process composed of two‐steps and that PMMA exercises a stabilizing effect on the thermal degradation of PVC during the first step by decreasing the rate of dehydrochlorination. J. VINYL ADDIT. TECHNOL., 25:E73–E82, 2019. © 2018 Society of Plastics Engineers
Weighted cross validation in model selection
Authors: Markatou Marianthi , Afendras Georgios , Agostinelli Claudio
Published: July 2018

Outliers and gross errors in the data, as well as deviations from the normality assumption of the error distribution, impact adversely statistical analyses that are based on classical procedures such as least squares and maximum likelihood methods. We briefly review the cross‐validation (CV) method to model selection and discuss its robust extension based on weighted likelihood methodology. The main advantage of weighted CV is that it is computationally fast, much faster than many of the robust model selection procedures proposed in the literature. We present the weighted CV algorithm, its operating characteristics, and illustrate its performance under symmetric and asymmetric contamination. The procedure, in the absence of contamination and under mild conditions, is asymptotically equivalent to the CV method for model selection. Additionally, it is asymptotically loss efficient and differs from the robust CV procedure introduced in the literature in that it downweights only those observations that do not fit well the full model.

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Modeling Methods and Algorithms

Statistical and Graphical Methods of Data Analysis > Robust Methods

Statistical Models > Linear Models

Statistical Models > Model Selection
Influence of Grain Refinement on Slurry Formation and Surface Segregation in Semi-solid Al-7Si-0.3Mg Castings
Authors: Santos Jorge , Kallien Lothar H. , Jarfors Anders E. W. , Dahle Arne K.
Published: July 2018

This study aims to evaluate the effect of grain refinement on slurry formation and surface segregation in semi-solid castings produced by the Rheometal™ process. The effect of two grain refiners, Al-8B and Al-5Ti-1B, on the slurry α-Al grain size, shape factor and solid fraction was evaluated. The results suggest that the addition of a grain refiner can affect the solid fraction obtained in the RheometalTM process and, consequently, reduce the solute content near the casting surface. Grain refiner addition resulted in a larger fraction of α-Al grains ≤ 60 µm for the refined alloys compared with the unrefined alloy. Additionally, the growth of α-Al slurry globules was greater for the unrefined alloy compared with the refined alloy during solidification in the die-cavity. A more homogeneous and finer microstructure was observed near the surface in the grain-refined castings compared with the unrefined castings. Evidence of significant liquid penetration was identified in some α-Al globules, indicating that disintegration of α-Al globules may occur during the Rheometal™ casting process.
Clean Sky research and demonstration programmes for next-generation aircraft engines
Authors: Brouckaert Jean-François , Mirville François , Phuah Kevin , Taferner Peter
Published: July 2018

The Clean Sky Joint Undertaking is currently managing two large-scale research and innovation programmes under FP7 and Horizon 2020 to contribute to the strengthening of the European aeronautical sector ensuring global leadership and competitiveness. This paper describes the research and demonstration programmes in Clean Sky (2008–2017) and Clean Sky 2 (2014–2024) related to propulsion technologies for the next-generation aircraft. The bulk of this work is addressed in Clean Sky 1 under the “Sustainable And Green Engines” (SAGE) programme and under the “ENGINES” programme in Clean Sky 2. The High-Level Objectives are described for each engine architecture as well as the targets in terms of CO2 and noise reduction versus a year 2000 reference unless stated otherwise. An overview of the new engine concepts that would satisfy the ACARE objectives is presented, including the main technologies which are to be developed to ensure the successful demonstration of each of those new engine concepts.
Xenophon in a Black Sea Landscape: Settlement Models for the Iron Age on the Sinop Promontory (Turkey)
Authors: Doonan Owen
Published: July 2018

Research into the Iron Age of Anatolia has seldom paid sufficient attention to settlement patterns and the social organization of space. TheAnabasisby Xenophon records the observations of a Greek outsider who travelled across eastern Anatolia and along the Black Sea coast in 400bce, a time that was relatively early in the colonial process in this area. Xenophon's observations are used to establish a basic model for settlement in the Black Sea coastal region of Anatolia, which is then tested against the results of recent archaeological surveys and related research on the Sinop promontory. A fuller and richer model of indigenous Iron Age settlement and colonial engagement on the Sinop promontory is developed and considered in light of recent research on colonization in the western Mediterranean and northern Black Sea regions.
BALANCING SOFT AND HARD LAW FOR BUSINESS AND HUMAN RIGHTS
Authors: Choudhury Barnali
Published: July 2018

In the wake of increasing corporate disasters, there has been an urgent need to address the impact of business on human rights. Yet business responsibilities for human rights are mainly voluntary and best understood as ‘soft law’. Recently, however, States have begun negotiations for an internationally binding treaty in this area, suggesting that there is a need to turn to ‘hard law’ to increase the efficacy of business and human rights (BHR) initiatives. This article argues that because soft and hard law concepts are not dichotomous, BHR governance need not become ‘hard law’ to be effective. Rather ‘hardened’ soft law instruments can be equally effective.
Weight loss after pregnancy: challenges and opportunities
Authors: McKinley Michelle C. , Allen-Walker Virginia , McGirr Caroline , Rooney Ciara , Woodside Jayne V.
Published: July 2018

It is important to pay attention to weight management before and between pregnancies, as women have an increased risk of weight gain during the reproductive years. Having a baby is a life-changing event for women and the challenge of weight management amidst this period of major physiological, psychological and social change should not be underestimated. However, the postpartum period offers an opportune time for lifestyle interventions, as women may have heightened awareness of their own and their wider families’ health. Systematic reviews indicate that interventions including both diet and physical activity along with individualised support and self-monitoring are more likely to be successful in promoting postpartum weight loss. However, high levels of attrition and poor engagement have been an issue in previous trials in this area. Since postpartum women are difficult to reach and retain, future research must consider how to make weight-management interventions an attractive and attainable proposition for women who are juggling multiple, competing demands on their time. Ideally, intervention approaches need to be flexible and allow sustained contact with women, to facilitate a focus on maintenance of weight loss, as well as opportunities for re-engagement after life events that may disrupt weight-management progress. Using technology to deliver or support interventions holds promise but trials are needed to generate a range of appealing, effective and scalable options for postpartum women. What works at other life stages may not necessarily work here owing to specific barriers to weight management encountered in the postpartum period.
Architecture's expanding field: AD magazine and the Post-Modernisation of architecture
Authors: Parnell Stephen
Published: July 2018

This article investigates architecture's ‘expanded field’ – its turn towards culture during the 1980s when the profession expanded its interest to the softer practices of architectural culture. It looks in particular at the emerging enterprises of exhibitions, competitions and awards, publications, and symposia and lectures in the ‘long 1980s’, taken as the Academy years of AD magazine from 1977 – 1992.

This period of AD is synonymous with architectural Post-Modernism, as Academy published much of Charles Jencks’ work on Post-Modernism, including six of the seven ever-larger editions of The Language of Post-Modern Architecture.

However, by analysing the content and context of AD magazine and the wider context of architectural institutions during these years, this article argues that the Post-Modernisation of architecture should be understood not only as a mere style, but equally as the emphasis on a growing architectural culture, discourse, and the ‘ideal’, and the retreat from building and the ‘real’. In other words, this period witnessed the establishment of architectural culture as a new type of practice, and furthermore, AD was instrumental in this cultural turn.
What Do We Really Know about Athenian Society?
Authors: Vlassopoulos Kostas
Published: July 2018

Traditional accounts of Athenian society tend to take their sources at face value, as direct reflections of Athenian reality. They present a model of free citizens working as independent producers, while the elite derived its surplus income from the exploitation of slaves. This model underestimates the systematic omissions of the sources, their consistent and distorting focus, and the implications of these biases. By mapping the field of vision of Athenian sources and the discourses that focus attention on certain aspects while leaving others in the shadows, this article offers an alternative methodology for reconstructing Athenian society. In particular, it considers the Athenian distinction between slave and free, arguing that the emphasis on a clear distinction between the two is not an automatic result of the significance of slavery in Athens. It also shows how the sources render invisible the large numbers of freemen that did not live as independent producers, and argues that there was a significant gap between the theoretically clear-cut distinction and its application in practice. A renewed approach to Athenian society needs to account for the dimensions that remain systematically beyond the sources’ field of vision. It must also take major conceptual distinctions like that between slave and free not as reflections of reality but as choices which relate to Athenian society's view of itself and require historical explanation.
The Postal Service in the Douar: Noncitizen Users and the Colonial State in Rural Algeria from the Late Nineteenth Century to the Second World War
Authors: Lacroix Annick
Published: July 2018

Throughout the colonial period, Algerian users are largely absent from the administrative archives of the Postal, Telegraph, and Telephone Service (PTT). If the French conquest did not spur colonized populations, with their ancient writing practices, to “enter into communication,” should this absence be understood as the refusal of a progress that was itself colonialist? The period between the two world wars marked a turning point: pressure from local representatives and a wave of petitions from noncitizen (Algerian) villagers reconfigured a public service previously monopolized by European users. Belatedly, and with as little expense as possible, the administration finally supported postal services for isolated areas.

Observing the colonial configuration in the most situated and ordinary of its manifestations, this article sheds light on everyday writing practices and reinstates the “thickness” of a local service. Rather than limiting the study to the French presence in Algeria, this depends on pressing the colonial documentation to reveal the workings of Algerian society and the reorganizations prompted by the colonial encounter. Complaints and petitions thus illuminate the relation of noncitizen, rural, and mostly illiterate populations to the colonial state. The unexpected utilization of the postal service and subversive demands for access to it led colonized populations to piece together a political identity that borrowed certain practices from active citizens and drove the French authorities to propose unprecedented adjustments.
Elites, Elitism, and Community in the Archaic Polis
Authors: Ma John
Published: July 2018

This article explores the famously diverse and expressive political cultures of the “Archaic” Greek communities (650 – 450 BCE) in the light of recent work on public goods and publicness, to which the present essay partly responds. This contribution may also be considered as a fragment of the long history of the Greekpolis. The distinction between “elitist” or “aristocratic” styles and “middling” or “popular” styles, upon closer examination, turns out to be a set of political play-acting gestures, predicated on different political institutions and notably on access to public goods. The “middling” styles paradoxically reflect restricted political access, while “aristocratic” competition in fact responds to the stress and uncertainties of broad enfranchisement. The whole nexus of issues and gestures surrounding distinction is hence not socially autonomous, but immediately linked to political requirements and institutional pressures. This article thus argues not just for the centrality of public goods topolisformation in early Greece, but also for the centrality of formal access and entitlements to the “public thing”—in other words, for the centrality of the state and its potential development. Putting the “state” back in the early history of the Greek city-state: the exercise has its own risks (notably that of teleology), but it attempts to avoid problems arising in recent histories of thepolis, where the state is downplayed or indeed dismissed altogether, and thepolisitself reduced to a pure phenomenon of elite capture or elite constitution.
Projected Heat Stress Under 1.5 °C and 2 °C Global Warming Scenarios Creates Unprecedented Discomfort for Humans in West Africa
Authors: Sylla Mouhamadou Bamba , Faye Aissatou , Giorgi Filippo , Diedhiou Arona , Kunstmann Harald
Published: July 2018

Heat and discomfort indices are applied to the multimodel ensemble mean of COordinated Regional climate Downscaling EXperiment‐Africa regional climate model projections to investigate future changes in heat stress and the proportion of human population at risk under 1.5 °C and 2 °C global warming scenarios over West Africa. The results show that heat stress of category Extreme Caution is projected to extend spatially (up to 25%) over most of the Gulf of Guinea, Sahel, and Sahara desert areas, with different regional coverage during the various seasons. Similarly, the projected seasonal proportion of human population at discomfort substantially increases to more than 50% over most of the region. In particular, in June–August over the Sahel and the western Sahara desert, new areas (15% of West Africa) where most of the population is at risk emerge. This indicates that from 50% to almost everyone over most of the Sahel countries and part of the western Sahara desert is at risk of possible heat cramp, heat exhaustion, and heat stroke in future climate scenarios. These conditions become more frequent and are accompanied by the emergence of days with dangerous heat stress category during which everyone feels discomfort and is vulnerable to a likely heat cramp and heat exhaustion. In general, all the above features are more extended and more frequent in the 2 °C than in the 1.5 °C scenario. Protective measures are thus required for outdoor workers, occupational settings in hot environments, and people engaged in strenuous activities.
Using Technology to Teach Parents to Create a Safe Infant Sleep Space
Authors: Austin Jillian E. , Doering Jennifer J. , Davies W. Hobart
Published: July 2018

The American Academy of Pediatrics (AAP) published Recommendations for a Safe Infant Sleeping Environment; however, parents still report frequent use of dangerous infant sleep practices. An online computer program was developed and piloted to investigate whether parents could be taught to create safe sleep environments using online training. Computerized safe sleep environments created by parents of children 0 to 23 months were assessed for compliance with the AAP Sleep Recommendations. Using a pre- and posttest design, the present study investigated the effectiveness of online instructions (adapted standard of care) and a computerized behavioral skills training package, which included instructions, modeling, rehearsal, and feedback. Additional pre- and posttests assessed parents’ ability to identify sleep risks in 3 pictures to assess generalization of skills learned. Overall, participants demonstrated significant improvements from pre- to posttest across both treatment conditions on the creation of a safe sleep environment and on the free response identification of risks in 3 sleep environments. Performance did not significantly differ between the treatment groups. Results suggest considerable promise for technology-aided approaches in training parents to create a safe sleep environment.

Implications for Impact Statement

Creating safe infant sleep environments is important and necessary in reducing sudden and unexpected infant deaths. In this online study, caregivers created safer infant sleep environments and identified more sleep environment risks after computer-based training and when using a sleep safety checklist. Providing access to this computer-based training and/or sleep safety checklist can teach caregivers about infant sleep safety and may result in safer infant sleep environments.
Wavelength stability in a hybrid photonic crystal laser through controlled nonlinear absorptive heating in the reflector
Authors: Bakoz Andrei P. , Liles Alexandros A. , Gonzalez-Fernandez Alfredo A. , Habruseva Tatiana , Hu Changyu , Viktorov Evgeny A. , Hegarty Stephen P. , O’Faolain Liam
Published: July 2018

The need for miniaturized, fully integrated semiconductor lasers has stimulated significant research efforts into realizing unconventional configurations that can meet the performance requirements of a large spectrum of applications, ranging from communication systems to sensing. We demonstrate a hybrid, silicon  photonics-compatible photonic crystal (PhC) laser architecture that can be used to implement cost-effective, high-capacity light sources, with high side-mode suppression ratio and milliwatt output output powers. The emitted wavelength is set and controlled by a silicon PhC cavity-based reflective filter with the gain provided by a III–V-based reflective semiconductor optical amplifier (RSOA). The high power density in the laser cavity results in a significant enhancement of the nonlinear absorption in silicon in the high Q-factor PhC resonator. The heat generated in this manner creates a tuning effect in the wavelength-selective element, which can be used to offset external temperature fluctuations without the use of active cooling. Our approach is fully compatible with existing fabrication and integration technologies, providing a practical route to integrated lasing in wavelength-sensitive schemes.
A novel phosphorylation by AMP-activated kinase regulates RUNX2 from ubiquitination in osteogenesis over adipogenesis
Authors: Chava Suresh , Chennakesavulu S. , Gayatri B. Meher , Reddy Aramati B. M.
Published: July 2018

Mesenchymal stem cells (MSCs) function as progenitors to a variety of cell types. The reported association between osteogenic and adipogenic commitment during differentiation is due to the regulation of key transcription factors in the signaling pathways. However, the process of adipogenesis at the expense of osteogenic phenotype during metabolic stress is still unclear. In this study, we showed for the first time that RUNX2 is a novel substrate of AMP-activated kinase (AMPK), which directly phosphorylates at serine 118 residue in the DNA-binding domain of RUNX2. Our results in in vitro MSC lineage differentiation models confirmed that active AMPK and RUNX2-S118 phosphorylation are preferentially associated with osteogenic commitment, whereas the lack of this phosphorylation leads to adipogenesis. This interplay is regulated by the ubiquitination of non-phosphorylated RUNX2-S118, which is evident in the dominant mutant RUNX2-S118D. Pharmacological activation of AMPK by metformin significantly abrogated the loss of RUNX2-S118 phosphorylation and protected from tunicamycin-induced endoplasmic reticulum stress, high glucose-induced in vitro adipogenesis and streptozotocin-induced in vivo bone adiposity and bone phenotype. In conclusion, results from this study demonstrated that RUNX2 is a direct target of AMPK which simplified the outlook towards several complex mechanisms that are currently established concerning cellular metabolism and pathogenesis.
Downregulation of miR-130a, antagonized doxorubicin-induced cardiotoxicity via increasing the PPARγ expression in mESCs-derived cardiac cells
Authors: Pakravan Golnaz , Foroughmand Ali Mohammad , Peymani Maryam , Ghaedi Kamran , Hashemi Motahare-Sadat , Hajjari Mohammadreza , Nasr-Esfahani Mohammad Hossein
Published: July 2018

Doxorubicin (Dox) is a widely used powerful chemotherapeutic component for cancer treatment. However, its clinical application has been hampered due to doxorubicin-induced cardiomyopathy upon the cessation of chemotherapy. Previous studies revealed that PPARγ plays a crucial protective role in cardiomyocytes. Modulation of miRNA expression is an applicable approach for prohibition of toxicity induction. Therefore, the aim of present study is uprising of PPARγ transcript levels via manipulation of miRNAs to limit Dox-induced cardiotoxicity in mESCs-derived cardiac cells, as in vitro model cell to provide a simple direct approach for further clinical therapies. Based on bioinformatics data mining, eventually miR-130a was selected to target PPARγ. This miRNA is highly expressed in heart. The expression of miR-130a increases sharply upon Dox treatment while specific antagomiR-130a reverses Dox-induced reduced expression of PPARγ, cellular apoptosis, and inflammation. Our data strongly suggest that antagomiR-130a limits Dox-induced cellular toxicity via PPARγ upregulation and may have clinical relevance to limit in vivo Dox toxicity.
Nicotine aversion is mediated by GABAergic interpeduncular nucleus inputs to laterodorsal tegmentum
Authors: Wolfman Shannon L. , Gill Daniel F. , Bogdanic Fili , Long Katie , Al-Hasani Ream , McCall Jordan G. , Bruchas Michael R. , McGehee Daniel S.
Published: July 2018

Nicotine use can lead to dependence through complex processes that are regulated by both its rewarding and aversive effects. Recent studies show that aversive nicotine doses activate excitatory inputs to the interpeduncular nucleus (IPN) from the medial habenula (MHb), but the downstream targets of the IPN that mediate aversion are unknown. Here we show that IPN projections to the laterodorsal tegmentum (LDTg) are GABAergic using optogenetics in tissue slices from mouse brain. Selective stimulation of these IPN axon terminals in LDTg in vivo elicits avoidance behavior, suggesting that these projections contribute to aversion. Nicotine modulates these synapses in a concentration-dependent manner, with strong enhancement only seen at higher concentrations that elicit aversive responses in behavioral tests. Optogenetic inhibition of the IPN–LDTg connection blocks nicotine conditioned place aversion, suggesting that the IPN–LDTg connection is a critical part of the circuitry that mediates the aversive effects of nicotine.
Neutralization of the Plasmodium-encoded MIF ortholog confers protective immunity against malaria infection
Authors: Baeza Garcia Alvaro , Siu Edwin , Sun Tiffany , Exler Valerie , Brito Luis , Hekele Armin , Otten Gib , Augustijn Kevin , Janse Chris J. , Ulmer Jeffrey B. , Bernhagen Jürgen , Fikrig Erol , Geall Andrew , Bucala Richard
Published: July 2018

Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PMIF, which modulates the host inflammatory response to malaria. Using a novel RNA replicon-based vaccine, we show the impact of PMIF immunoneutralization on the host response and observed improved control of liver and blood-stage Plasmodium infection, and complete protection from re-infection. Vaccination against PMIF delayed blood-stage patency after sporozoite infection, reduced the expression of the Th1-associated inflammatory markers TNF-α, IL-12, and IFN-γ during blood-stage infection, augmented Tfh cell and germinal center responses, increased anti-Plasmodium antibody titers, and enhanced the differentiation of antigen-experienced memory CD4 T cells and liver-resident CD8 T cells. Protection from re-infection was recapitulated by the adoptive transfer of CD8 or CD4 T cells from PMIF RNA immunized hosts. Parasite MIF inhibition may be a useful approach to promote immunity to Plasmodium and potentially other parasite genera that produce MIF orthologous proteins.
Strong plates enhance mantle mixing in early Earth
Authors: Agrusta Roberto , van Hunen Jeroen , Goes Saskia
Published: July 2018

In the present-day Earth, some subducting plates (slabs) are flattening above the upper–lower mantle boundary at ~670 km depth, whereas others go through, indicating a mode between layered and whole-mantle convection. Previous models predicted that in a few hundred degree hotter early Earth, convection was likely more layered due to dominant slab stagnation. In self-consistent numerical models where slabs have a plate-like rheology, strong slabs and mobile plate boundaries favour stagnation for old and penetration for young slabs, as observed today. Here we show that such models predict slabs would have penetrated into the lower mantle more easily in a hotter Earth, when a weaker asthenosphere and decreased plate density and strength resulted in subduction almost without trench retreat. Thus, heat and material transport in the Earth’s mantle was more (rather than less) efficient in the past, which better matches the thermal evolution of the Earth.
Nonstimulatory peptide–MHC enhances human T-cell antigen-specific responses by amplifying proximal TCR signaling
Authors: Zhao Xiang , Sankaran Shvetha , Yap Jiawei , Too Chien Tei , Ho Zi Zong , Dolton Garry , Legut Mateusz , Ren Ee Chee , Sewell Andrew K. , Bertoletti Antonio , MacAry Paul A. , Brzostek Joanna , Gascoigne Nicholas R. J.
Published: July 2018

Foreign antigens are presented by antigen-presenting cells in the presence of abundant endogenous peptides that are nonstimulatory to the T cell. In mouse T cells, endogenous, nonstimulatory peptides have been shown to enhance responses to specific peptide antigens, a phenomenon termed coagonism. However, whether coagonism also occurs in human T cells is unclear, and the molecular mechanism of coagonism is still under debate since CD4 and CD8 coagonism requires different interactions. Here we show that the nonstimulatory, HIV-derived peptide GAG enhances a specific human cytotoxic T lymphocyte response to HBV-derived epitopes presented by HLA-A*02:01. Coagonism in human T cells requires the CD8 coreceptor, but not T-cell receptor (TCR) binding to the nonstimulatory peptide–MHC. Coagonists enhance the phosphorylation and recruitment of several molecules involved in the TCR-proximal signaling pathway, suggesting that coagonists promote T-cell responses to antigenic pMHC by amplifying TCR-proximal signaling.
Perspective: bidirectional exosomal transport between cancer stem cells and their fibroblast-rich microenvironment during metastasis formation
Authors: Valcz Gábor , Buzás Edit Irén , Szállási Zoltán , Kalmár Alexandra , Krenács Tibor , Tulassay Zsolt , Igaz Péter , Molnár Béla
Published: July 2018

Carcinomas are complex structures composed of hierarchically organized distinct cell populations such as cancer stem cells and non-stem (bulk) cancer cells. Their genetic/epigenetic makeup and the dynamic interplay between the malignant cell populations and their stromal fibroblasts are important determinants of metastatic tumor invasion. Important mediators of these interactions are the small, membrane-enclosed extracellular vesicles, in particular exosomes. Both cancer cell and fibroblast-derived exosomes carry a set of regulatory molecules, including proteins and different species of RNA, which cooperatively support metastatic tumor spread. Here, we briefly overview potential links between cancer stem cells and the exosome-mediated fibroblast-enriched metastatic niche formation to discuss their role in the promotion of tumor growth and metastatic expansion in breast carcinoma models.
Author Correction: Increased food supply mitigates ocean acidification effects on calcification but exacerbates effects on growth
Authors: Brown Norah E. M. , Bernhardt Joey R. , Anderson Kathryn M. , Harley Christopher D. G.
Published: July 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Revealing the complex genetic structure of cultivated amaryllis (Hippeastrum hybridum) using transcriptome-derived microsatellite markers
Authors: Wang Yi , Chen Defeng , He Xiaofeng , Shen Jiangxian , Xiong Min , Wang Xian , Zhou Di , Wei Zunzheng
Published: July 2018

Although amaryllis (Hippeastrum hybridum) plants are commonly used in physiological and ecological research, the extent of their genomic and genetic resources remains limited. The development of molecular markers is therefore of great importance to accelerate genetic improvements in Hippeastrum species. In this study, a total of 269 unique genes were defined that might regulate the flower spathe development of amaryllis. In addition, 2000 simple sequence repeats (SSRs) were detected based on 171,462 de novo assembled unigenes from transcriptome data, and 66,4091 single nucleotide polymorphisms (SNPs) were also detected as putative molecular markers. Twenty-one SSR markers were screened to evaluate the genetic diversity and population structure of 104 amaryllis accessions. A total of 98 SSR loci were amplified for all accessions. The results reveal that Nei’s gene diversity (H) values of these markers ranged between 0.055 and 0.394, whereas the average values of Shannon’s Information index (I) ranged between 0.172 and 0.567. Genetic tree analysis further demonstrates that all accessions can be grouped into three main clusters, which can be further divided into two subgroups. STRUCTURE-based analysis revealed that the highest ΔK values were observed when K = 5, K = 6, K = 7 and K = 8. The results of this study enable large-scale transcriptomics and classification of Hippeastrum genetic polymorphisms and will be useful in the future for resource conservation and production.
Improving the efficiency of rear emitter silicon solar cell using an optimized n-type silicon oxide front surface field layer
Authors: Kim Sangho , Park Jinjoo , Phong Pham Duy , Shin Chonghoon , Iftiquar S. M. , Yi Junsin
Published: July 2018

Optical and electrical characteristics of n-type nano-crystalline-silicon oxide (n-µc-SiO:H) materials can be varied to optimize and improve the performance of a solar cell. In silicon heretojunction (SHJ) solar cells, it can be used to improve carrier selectivity and optical transmission at the front side, both of which are vitally important in device operation. For this purpose, the n-µc-SiO:H was investigated as the front surface field (FSF) layer. During film deposition, an increased CO2 flow rate from 0 to 6 sccm resulted in changes of crystalline volume fractions from 57 to 28%, optical band-gaps from 1.98 to 2.21 eV, dark conductivities from 7.29 to 1.1 × 10−5 S/cm, and activation energies from 0.019 to 0.29 eV, respectively. In device applications, a minimum optical reflection was estimated for the FSF layer that was fabricated with 4 sccm CO2 (FSF-4), and therefore obtained the highest external quantum efficiency, although short circuit current density (Jsc) was 38.83 mA/cm2 and power conversion efficiency (PCE) was 21.64%. However, the highest PCE of 22.34% with Jsc = 38.71 mA/cm2 was observed with the FSF prepared with 2 sccm CO2 (FSF-2), as the combined opto-electronic properties of FSF-2 were better than those of the FSF-4.
Quantum Zeno Effect assisted Spectroscopy of a single trapped Ion
Authors: Ozawa Akira , Davila-Rodriguez Josue , Hänsch Theodor W. , Udem Thomas
Published: July 2018

The quantum Zeno effect (QZE) is not only interesting as a manifestation of the counterintuitive behavior of quantum mechanics, but may also have practical applications. When a spectroscopy laser is applied to target atoms or ions prepared in an initial state, the Rabi flopping of an auxiliary transition sharing one common level can be inhibited. This effect is found to be strongly dependent on the detuning of the spectroscopy laser and offers a sensitive spectroscopy signal which allows for high precision spectroscopy of transitions with a small excitation rate. We demonstrate this method with direct frequency comb spectroscopy using the minute power of a single mode to drive a dipole allowed transition in a single trapped ion. Resolving the individual modes of the frequency comb demonstrates that the simple instantaneous quantum collapse description of the QZE can not be applied here, as these modes need several pulses to build up.
Integrated deep visual and semantic attractor neural networks predict fMRI pattern-information along the ventral object processing pathway
Authors: Devereux Barry J. , Clarke Alex , Tyler Lorraine K.
Published: July 2018

Recognising an object involves rapid visual processing and activation of semantic knowledge about the object, but how visual processing activates and interacts with semantic representations remains unclear. Cognitive neuroscience research has shown that while visual processing involves posterior regions along the ventral stream, object meaning involves more anterior regions, especially perirhinal cortex. Here we investigate visuo-semantic processing by combining a deep neural network model of vision with an attractor network model of semantics, such that visual information maps onto object meanings represented as activation patterns across features. In the combined model, concept activation is driven by visual input and co-occurrence of semantic features, consistent with neurocognitive accounts. We tested the model’s ability to explain fMRI data where participants named objects. Visual layers explained activation patterns in early visual cortex, whereas pattern-information in perirhinal cortex was best explained by later stages of the attractor network, when detailed semantic representations are activated. Posterior ventral temporal cortex was best explained by intermediate stages corresponding to initial semantic processing, when visual information has the greatest influence on the emerging semantic representation. These results provide proof of principle of how a mechanistic model of combined visuo-semantic processing can account for pattern-information in the ventral stream.
Neonatal anesthesia exposure impacts brain microRNAs and their associated neurodevelopmental processes
Authors: Lin Daisy , Liu Jinyang , Hu Zihua , Cottrell James E. , Kass Ira S.
Published: July 2018

MicroRNAs (miRNAs), when subjected to environmental stimuli, can exhibit differential expression. As critical regulators of gene expression, differential miRNA expression has been implicated in numerous disorders of the nervous system. In this study, we focused on the effect of a general anesthetic, as an environmental stimulus, on miRNA expression of the developing brain. General anesthetics have potential long-lasting neurotoxic effects on the developing brain, resulting in behavioral changes in adulthood. We first carried out an unbiased profiling approach to examine the effect of single-episode neonatal general anesthetic, sevoflurance (sevo), exposure on miRNA expression of the brain. Neonatal sevo has a significant effect on the expression of specific miRNAs of the whole brain and the hippocampus that is both immediate – directly after neonatal treatment, as well as long-lasting - during adulthood. Functionally, neonatal sevo-associated miRNA gene-targets share potential neurodevelopmental pathways related to axon guidance, DNA transcription, protein phosphorylation and nervous system development. Our understanding on the role of miRNAs provides a putative epigenetic/molecular bridge that links neonatal general anesthetic’s effect with its associated functional change.