bluuebunny/crossref_metadata_2025 huggingface dataset:
Silicon modulates multi-layered defense against powdery mildew in Arabidopsis
Authors: Wang Lili , Dong Min , Zhang Qiong , Wu Ying , Hu Liang , Parson James F , Eisenstein Edward , Du Xiangge , Xiao Shunyuan
Published: February 2020

Silicon (Si) has been widely employed in agriculture to enhance resistance against pathogens in many crop plants. However, the underlying molecular mechanisms of Si-mediated resistance remain elusive. In this study, the Arabidopsis-powdery mildew pathosystem was employed to investigate possible defense mechanisms engaged for Si-mediated resistance. Because Arabidopsis lacks efficient Si transporters and thus is a low Si-accumulator, two heterologous Si influx transporters (from barley and muskmelon) were individually expressed in wild-type Arabidopsis Col-0 and a panel of mutants defective in different immune signaling pathways. Results from infection tests showed that while very low leaf Si content slightly induced salicylic acid (SA)-dependent resistance, high Si promoted PAD4-dependent but EDS1- and SA-independent resistance against the adapted powdery mildew isolateGolovinomyces cichoracearum UCSC1. Intriguingly, our results also showed that high Si could largely reboot non-host resistance in an immune-compromisededs1/pad4/sid2triple mutant background against a non-adapted powdery mildew isolateG. cichoracearumUMSG1. Taken together, our results suggest that assimilated Si modulates distinct, multi-layered defense mechanisms to enhance plant resistance against adapted and no-adapted powdery mildew pathogens, possibly via synergistic interaction with defense-induced callose
Mucosal-associated invariant T (MAIT) cells mediate protective host responses in sepsis
Authors: Trivedi Shubhanshi , Labuz Daniel , Anderson Cole P. , Araujo Claudia V. , Blair Antoinette , Middleton Elizabeth A. , Tran Alex , Mulvey Matthew A. , Campbell Robert A. , Hale J. Scott , Rondina Matthew T. , Leung Daniel T.
Published: February 2020

Sepsis is a systemic inflammatory response to infection and a leading cause of death. Mucosal-associated invariant T (MAIT) cells are innate-like T cells enriched in mucosal tissues that recognize bacterial ligands. We investigated MAIT cells during clinical and experimental sepsis, and their contribution to host responses. In experimental sepsis, MAIT-deficient mice had significantly increased mortality and bacterial load, and reduced tissue-specific cytokine responses. MAIT cells of WT mice expressed lower levels of IFN-γ and IL-17a during sepsis compared to sham surgery, changes not seen in non-MAIT T cells. MAIT cells of patients presenting with sepsis were significantly reduced in frequency, more activated, and had decreased IFN-γ production when stimulated, compared to healthy donors and paired 90-day post-sepsis samples. Our data suggest that MAIT cells are highly activated and become dysfunctional during clinical sepsis, and contribute to tissue-specific cytokine responses that are protective against mortality during experimental sepsis.
The Endothelial Protein C Receptor plays an essential role in the maintenance of Pregnancy
Authors: Castillo Michelle M , Yang Qiuhui , Sigala Abril Solis , McKinney Dosia T , Zhan Min , Chen Kristen L , Jarzembowski Jason A , Sood Rashmi
Published: February 2020

Placenta-mediated pregnancy complications are a major challenge in the management of maternal-fetal health. Maternal thrombophilia is a suspected risk factor but the role of thrombotic processes in these complications and the potential for antithrombotic treatment have remained unclear. Endothelial Protein C Receptor (EPCR) is an anticoagulant protein highly expressed in the placenta. EPCR autoantibodies and specific gene variants of EPCR are associated with poor pregnancy outcomes. In mice, fetal EPCR deficiency results in placental failure andin uterodeath. Adult EPCR-deficient mice generated by maintaining placental expression exhibit plasma markers of thrombophilia without overt thrombosis. We demonstrate that inactivation of clotting factor VIII or Protease Activated Receptor 4 (Par4), Par3 or integrin αIIb in the mother allows placental development and intrauterine survival of murine embryos lacking EPCR. Rescued EPCR-deficient embryos exhibit thrombosis in placental venous sinuses at late gestation and a high rate of neonatal lethality. In contrast to fetal EPCR deficiency, maternal deficiency of EPCR results in frequent stillbirths and maternal death accompanied by pathological findings that resemble placental abruption and consumptive coagulopathy. Inactivation of Par4, but not clotting factor VIII, prevents maternal death and restores normal pregnancy outcomes. These observations establish a cause-effect relationship between maternal thrombophilia and placental abruption. They demonstrate that sites of uteroplacental thrombosis and the potential response to antithrombotic intervention may differ with gestational age and maternal versus fetal origin of thrombophilia. Our findings highlight the potential for therapeutic inhibition of thrombin-mediated platelet activation in a subset of pregnancy complications.

KEY POINTS

Murine model establishes a cause-effect relationship between maternal thrombophilia, retroplacental hemorrhage and severe pregnancy complications.

Thrombin-mediated activation of maternal platelets is a key event in thrombophilia-associated pregnancy complications and a potential target of therapeutic intervention.

Maternal venous channels in uteroplacental circulation are additional sites of thrombotic pathology associated with adverse neonatal outcomes.
Direct Observation Of Vesicle Transport On The Synaptic Ribbon Provides Evidence That Vesicles Are Mobilized And Prepared Rapidly For Release
Authors: Joselevitch Christina , Zenisek David
Published: February 2020

Synaptic ribbons are thought to provide vesicles for continuous synaptic transmission in some retinal non-spiking neurons, yet recent studies indicate that genetic removal of the ribbon has little effect on vesicle release kinetics. To investigate vesicle replenishment at synaptic ribbons, we imaged synaptic vesicles and ribbons in retinal bipolar cells with TIRF microscopy during stimulation with trains of 30-ms depolarizations. Analysis of vesicles released by the stimuli revealed that the vast majority of releasable vesicles reside within 300 nm of the ribbon center. A single 30-ms step to 0 mV was sufficient to deplete the most membrane-proximal vesicle pool, while triggering rapid stepwise movements of distal vesicles along the ribbon and toward the plasma membrane.

Replenishment only becomes rate-limiting for recovery from paired-pulse depression for interstimulus intervals shorter than 250 ms. For longer interstimulus intervals, vesicle movement down the ribbon is fast enough to replenish released vesicles, but newly arrived vesicles are not release-ready. Notably, vesicle re-supply is 40-to 50-fold faster than previously measured in non-ribbon conventional synapses, whereas vesicle maturation rate is comparable. Moreover, in contrast to conventional synapses, vesicles docked at the base of the ribbon release with high fidelity. Lastly, our data show that with multiple stimuli, the delay in vesicle departure increases. Our results support a role for ribbons in the rapid supply and efficient preparation of vesicles for release, provide direct measurements of vesicle movement down the synaptic ribbon and suggest that multiple factors contribute to paired-pulse depression.
Bud23 promotes the progression of the Small Subunit Processome to the pre-40S ribosome inSaccharomyces cerevisiae
Authors: Black Joshua J. , Sardana Richa , Elmir Ezzeddine W. , Johnson Arlen W.
Published: February 2020

The first metastable assembly intermediate of the eukaryotic ribosomal small subunit (SSU) is the SSU Processome, a large complex of RNA and protein factors that is thought to represent an early checkpoint in the assembly pathway. Transition of the SSU Processome towards continued maturation requires the removal of the U3 snoRNA and biogenesis factors as well as ribosomal RNA processing. While the factors that drive these events are largely known, how they do so is not well understood. The methyltransferase Bud23 has a role during this transition, but its function, beyond the nonessential methylation of 18S rRNA, is not characterized. Here, we have carried out a comprehensive genetic screen to understand Bud23 function. We identified 67 unique extragenicbud23Δ-suppressing mutations that mapped to genes encoding the SSU Processome factorsDHR1, IMP4, UTP2(NOP14),BMS1and the SSU proteinRPS28A. These factors form a physical interaction network that links the binding site of Bud23 to the U3 snoRNA and many of the suppressing mutations weaken protein-protein and protein-RNA interactions. Importantly, this network links Bud23 to the GTPase Bms1 and the RNA helicase Dhr1. Bms1 is thought to drive conformational changes to promote rRNA cleavage, and we previously showed that Dhr1 is required for unwinding the U3 snoRNA. Moreover, particles isolated from cells lacking Bud23 accumulated late SSU Processome factors and pre-rRNAs not cleaved at sites A1 and A2. We propose a model in which Bud23 dissociates factors surrounding its binding site to promote SSU Processome progression.

Author summary

Ribosomes are the molecular machines that synthesize proteins and are composed of a large and a small subunit which carry out the essential functions of polypeptide synthesis and mRNA decoding, respectively. Ribosome production is tightly linked to cellular growth as cells must produce enough ribosomes to meet their protein needs. However, ribosome assembly is a metabolically expensive pathway that must be balanced with other cellular energy needs and regulated accordingly. In eukaryotes, the small subunit (SSU) Processome is a metastable intermediate that ultimately progresses towards a mature SSU through the release of biogenesis factors. The decision to progress the SSU Processome is thought to be an early checkpoint in the SSU assembly pathway, but what drives this checkpoint is unknown. Previous studies suggest that Bud23 plays an uncharacterized role during SSU Processome progression. Here, we used a genetic approach to understand its function and found that Bud23 is connected to a network of factors that stabilize the particle. Interestingly, two of these factors are enzymes that facilitate structural rearrangements needed for progression. We conclude that Bud23 promotes the release of factors surrounding its binding site to drive rearrangements during the progression of the SSU Processome.
Escherichia coli σ38promoters use two UP elements instead of a −35 element: resolution of a paradox and discovery thatσ38transcribes ribosomal promoters
Authors: Franco Kevin S. , Sun Zhe , Chen Yixiong , Cagliero Cedric , Zuo Yuhong , Zhou Yan Ning , Kashlev Mikhail , Jin Ding Jun , Schneider Thomas D.
Published: February 2020

1

InE. coli, one RNA polymerase (RNAP) transcribes all RNA species, and different regulons are transcribed by employing different sigma (σ) factors. RNAP containingσ38(σS) activates genes responding to stress conditions such as stationary phase. The structure ofσ38promoters has been controversial for more than two decades. To construct a model ofσ38promoters using information theory, we aligned proven transcriptional start sites to maximize the sequence information, in bits, and identified a −10 element similar toσ70promoters. We could not align any −35 sequence logo; instead we found two patterns upstream of the −35 region. These patterns have dyad symmetry sequences and correspond to the location of UP elements in ribosomal RNA (rRNA) promoters. Additionally the UP element dyad symmetry suggests that the two polymeraseαsubunits, which bind to the UPs, should have two-fold dyad axis of symmetry on the polymerase and this is indeed observed in an X-ray crystal structure. Curiously theαCTDs should compete for overlapping UP elements.In vitroexperiments confirm thatσ38recognizes therrnBP1 promoter, requires a −10, UP elements and no −35. This clarifies the long-standing paradox of howσ38promoters differ from those ofσ70.
Random access DNA memory in a scalable, archival file storage system
Authors: Banal James L. , Shepherd Tyson R. , Berleant Joseph , Huang Hellen , Reyes Miguel , Ackerman Cheri M. , Blainey Paul C. , Bathe Mark
Published: February 2020

DNA is an ultra-high-density storage medium that could meet exponentially growing worldwide demand for archival data storage if DNA synthesis costs declined sufficiently and random access of files within exabyte-to-yottabyte-scale DNA data pools were feasible. To overcome the second barrier, here we encapsulate data-encoding DNA file sequences within impervious silica capsules that are surface-labeled with single-stranded DNA barcodes. Barcodes are chosen to represent file metadata, enabling efficient and direct selection of sets of files with Boolean logic. We demonstrate random access of image files from an image database using fluorescence sorting with selection sensitivity of 1 in 106files, which thereby enables 1 in 106NperNoptical channels. Our strategy thereby offers retrieval of random file subsets from exabyte and larger-scale long-term DNA file storage databases, offering a scalable solution for random-access of archival files in massive molecular datasets.
Genome sequence analysis of a giant-rooted ‘Sakurajima daikon’ radish (Raphanus sativus)
Authors: Shirasawa Kenta , Hirakawa Hideki , Fukino Nobuko , Kitashiba Hiroyasu , Isobe Sachiko
Published: February 2020

Daikon radish (Raphanus sativus) roots vary in size and shape between cultivars. This study reports the genome sequence assembly of a giant-rooted ‘Sakurajima daikon’ radish variety, ‘Okute-Sakurajima’, which produces extremely large round roots. Radish genome assembly is hampered by the repetitive and complex nature of the genome. To address this, single-molecule real-time technology was used to obtain long-read sequences at 60× genome coverage.De novoassembly of the long reads generated 504.5 Mb contig sequences consisting of 1,437 sequences with contig N50 length of 1.2 Mb, including 94.1% of the core eukaryotic genes. Nine pseudomolecule sequences, comprising 69.3% of the assembled contig length, were generated with high-density SNP genetic maps. The chromosome-level sequences revealed structure variations and rearrangements among Brassicaceae genomes. In total, 89,915 genes were predicted in the ‘Okute-Sakurajima’ genome, 30,033 of which were unique to the assembly in this study. The improved genome information generated in this study will not only form a new baseline resource for radish genomics, but will also provide insights into the molecular mechanisms underlying formation of giant radish roots.
Loss of Sister Kinetochore Co-orientation and Peri-centromeric Cohesin Protection after Meiosis I Depends on Cleavage of Centromeric REC8
Authors: Ogushi Sugako , Rattani Ahmed , Godwin Jonathan , Metson Jean , Schermelleh Lothar , Nasmyth Kim
Published: February 2020

Protection of peri-centromeric REC8 cohesin from separase and sister kinetochore attachment to microtubules emanating from the same spindle pole (co-orientation) ensure that sister chromatids remain associated after meiosis I. Both features are lost during meiosis II, when sister kinetochores bi-orient and lose peri-centromeric REC8 protection, resulting in sister chromatid disjunction and the production of haploid gametes. By transferring spindle-chromosome complexes (SCCs) between meiosis I and II cells, we have discovered that both sister kinetochore co-orientation and peri-centromeric cohesin protection depend on the SCC and not the cytoplasm. Moreover, the catalytic activity of separase at meiosis I is necessary not only for converting kinetochores from a co-to a bi-oriented state but also for deprotection of peri-centromeric cohesin and that cleavage of REC8 may be the key event. Crucially, we show that selective cleavage of REC8 in the vicinity of kinetochores is sufficient to destroy co-orientation in univalent chromosomes, albeit not in bivalents where resolution of chiasmata through cleavage of Rec8 along chromosome arms may also be required.
Freshwater monitoring by nanopore sequencing
Authors: Urban Lara , Holzer Andre , Baronas J Jotautas , Hall Michael , Braeuninger-Weimer Philipp , Scherm Michael J , Kunz Daniel J , Perera Surangi N , Martin-Herranz Daniel E , Tipper Edward T , Salter Susannah J , Stammnitz Maximilian R
Published: February 2020

While traditional microbiological freshwater tests focus on the detection of specific bacterial indicator species, including pathogens, direct tracing of all aquatic DNA through metagenomics poses a profound alternative. Yet,in situmetagenomic water surveys face substantial challenges in cost and logistics. Here we present a simple, fast, cost-effective and remotely accessible freshwater diagnostics workflow centred around the portable nanopore sequencing technology. Using defined compositions and spatiotemporal microbiota from surface water of an example river in Cambridge (UK), we provide optimised experimental and bioinformatics guidelines, including a benchmark with twelve taxonomic classification tools for nanopore sequences. We find that nanopore metagenomics can depict the hydrological core microbiome and fine temporal gradients in line with complementary physicochemical measurements. In a public health context, these data feature relevant sewage signals and pathogen maps at species level resolution. We anticipate that this framework will gather momentum for new environmental monitoring initiatives using portable devices.
Response ofAsplenium nidusto Drought Stress and Identification of Drought Tolerance Genes
Authors: Liang Jingwen , Yu Wengang , Wang Peng , Yu Xudong , Cai Zeping , Xu Shitao
Published: February 2020

To explore howAsplenium nidusresponds to drought stress, and to mine drought-responsive genes forAsplenium nidus, we conducted a pot experiment in the IOT smart greenhouse. We measured a series of physiological and biochemical indexes for drought-treated plants, and analyzed the expression of drought-responsive genes inAsplenium nidusby RT-qPCR. The results show that theAsplenium nidusis a species with drought tolerance.Asplenium nidusinhibits plant photosynthesis and reduces life activities by limiting stomatal opening to adapt to drought. To resist drought stress, theAsplenium niduschanges the osmotic potential by increasing the proline content to maintain normal metabolic activities and prevents the damage of active oxygen by increasing the enzyme activities of SOD and POD. Based on the analysis of the relative expression levels of genes,AVP1-2andAVP1-4may be drought-resistant genes inAsplenium nidus. This study lays the foundation for in-depth research on drought tolerance mechanisms and drought-resistant gene mining ofAsplenium nidus.
Structure-function analysis of the maize bulliform cell cuticle and its role in dehydration and leaf rolling
Authors: Matschi Susanne , Vasquez Miguel F. , Bourgault Richard , Steinbach Paul , Chamness James , Kaczmar Nicholas , Gore Michael A. , Molina Isabel , Smith Laurie G.
Published: February 2020

The cuticle is a hydrophobic layer on the outer surface plant shoots, which serves as an important interaction interface with the environment. It consists of the lipid polymer cutin, embedded with and covered by waxes, and provides protection against stresses including desiccation, UV radiation, and pathogen attack. Bulliform cells form in longitudinal strips on the adaxial leaf surface, and have been implicated in the leaf rolling response observed in drought stressed grass leaves. In this study, we show that bulliform cells of the adult maize leaf epidermis have a specialized cuticle, and we investigate its function along with that of bulliform cells themselves. Analysis of natural variation was used to relate bulliform strip pattering to leaf rolling rate, providing evidence of a role for bulliform cells in leaf rolling. Bulliform cells displayed increased shrinkage compared to other epidermal cell types during dehydration of the leaf, providing a potential mechanism to facilitate leaf rolling. Comparisons of cuticular conductance between adaxial and abaxial leaf surfaces, and between bulliform-enriched mutants vs. wild type siblings, provided evidence that bulliform cells lose water across the cuticle more rapidly than other epidermal cell types. Bulliform cell cuticles have a distinct ultrastructure, and differences in cutin monomer content and composition, compared to other leaf epidermal cells. We hypothesize that this cell type-specific cuticle is more water permeable than the epidermal pavement cell cuticle, facilitating the function of bulliform cells in stress-induced leaf rolling observed in grasses.

One sentence summary

Bulliform cells in maize have a specialized cuticle, lose more water than other epidermal cell types as the leaf dehydrates, and facilitate leaf rolling upon dehydration.
Determinants for forming a supramolecular myelin-like proteolipid lattice
Authors: Ruskamo Salla , Krokengen Oda C. , Kowal Julia , Nieminen Tuomo , Lehtimäki Mari , Raasakka Arne , Dandey Venkata P. , Vattulainen Ilpo , Stahlberg Henning , Kursula Petri
Published: February 2020

Myelin protein P2 is a peripheral membrane protein of the fatty acid binding protein family. It functions in the formation and maintenance of the peripheral nerve myelin sheath, and several P2 mutations causing human Charot-Marie-Tooth neuropathy have been reported. Here, electron cryomicroscopy of myelin-like proteolipid multilayers revealed a three-dimensionally ordered lattice of P2 molecules between stacked lipid bilayers, visualizing its possible assembly at the myelin major dense line. A single layer of P2 is inserted between two bilayers in a tight intermembrane space of ∼3 nm, implying direct interactions between P2 and two membrane surfaces. Further details on lateral protein organization were revealed through X-ray diffraction from bicelles stacked by P2. Surface mutagenesis of P2 coupled to structural and functional experiments revealed a role for both the portal region and the opposite face of P2 in membrane interactions. Atomistic molecular dynamics simulations of P2 on myelin-like and model membrane surfaces suggested that Arg88 is an important residue for P2-membrane interactions, in addition to the helical lid domain on the opposite face of the molecule. Negatively charged myelin lipid headgroups anchor P2 stably on the bilayer surface. Membrane binding may be accompanied by opening of the P2 β barrel structure and ligand exchange with the apposing lipid bilayer. Our results provide an unprecedented view into an ordered, multilayered biomolecular membrane system induced by the presence of a peripheral membrane protein from human myelin. This is an important step towards deciphering the 3-dimensional assembly of a mature myelin sheath at the molecular level.
Build me up to break me down: Frothed spawn in the sandpaper frog,Lechriodus fletcheri, is formed by female parents and later broken down by their offspring
Authors: Gould John
Published: February 2020

Several genera of anuran amphibians deposit their eggs within mucous secretions that have been aerated by the parents to produce a foam or bubble spawn body. This is a dynamic medium for embryo development given that is gradually breaks down over time, and one that has been hypothesised to serve a variety of purposes including protecting embryos from external stresses. In this study, I provide additional details of bubble spawn production in the sandpaper frog,Lechriodus fletcheri. Field and laboratory observations showed that females aerate spawn while in inguinal amplexus, using flanged fingers to transport air bubbles into the mucous. While the frothed spawn is initially resistant to breakup, it gradually loses bubbles and flattens out into a film. This temporal shift in structure is likely to be adaptive, as the resultant increase in surface area allows embryos to come in direct contact with the open water, which may accommodate their increased oxygen demands or facilitate hatching. I provide evidence that this process is controlled by the residing embryos, given that spawn in their absence does not breakdown, highlighting the ability of offspring to modify their immediate environment even before hatching to ensure conditions remain suitable for their changing needs.
PGC1/PPAR Drive Cardiomyocyte Maturation through Regulation of Yap1 and SF3B2
Authors: Murphy Sean , Miyamoto Matthew , Kervadec Anais , Kannan Suraj , Tampakakis Emmanouil , Kambhampati Sandeep , Lin Brian Leei , Paek Sam , Andersen Peter , Lee Dong-Ik , Zhu Renjun , An Steven S. , Kass David A. , Uosaki Hideki , Colas Alexandre R. , Kwon Chulan
Published: February 2020

Cardiomyocytes undergo significant levels of structural and functional changes after birth—fundamental processes essential for the heart to produce the volume and contractility to pump blood to the growing body. However, due to the challenges in isolating single postnatal/adult myocytes, how individual newborn cardiomyocytes acquire multiple aspects of mature phenotypes remains poorly understood. Here we implemented large-particle sorting and analyzed single myocytes from neonatal to adult hearts. Early myocytes exhibited a wide-ranging transcriptomic and size heterogeneity, maintained until adulthood with a continuous transcriptomic shift. Gene regulatory network analysis followed by mosaic gene deletion revealed that peroxisome proliferator-activated receptor coactivator-1 signaling—activated in vivo but inactive in pluripotent stem cell-derived cardiomyocytes—mediates the shift. The signaling regulated key aspects of cardiomyocyte maturation simultaneously through previously unrecognized regulators, including Yap1 and SF3B2. Our study provides a single-cell roadmap of heterogeneous transitions coupled to cellular features and unveils a multifaceted regulator controlling cardiomyocyte maturation.

Significance Statement

How the individual single myocytes achieve full maturity remains a ‘black box’, largely due to the challenges with the isolation of single mature myocytes. Understanding this process is particularly important as the immaturity and early developmental arrest of pluripotent stem cell-derived myocytes has emerged a major concern in the field. Here we present the first study of high-quality single-cell transcriptomic analysis of cardiac muscle cells from neonatal to adult hearts. We identify a central transcription factor and its novel targets that control key aspects of myocyte maturation, including cellular hypertrophy, contractility, and mitochondrial activity.
Identifying Informative Gene Modules Across Modalities of Single Cell Genomics
Authors: DeTomaso David , Yosef Nir
Published: February 2020

Two fundamental aims that emerge when analyzing single-cell RNA-seq data are that of identifying which genes vary in an informative manner and determining how these genes organize into modules. Here we propose a general approach to these problems that operates directly on a given metric of cell-cell similarity, allowing for its integration with any method (linear or non linear) for identifying the primary axes of transcriptional variation between cells. Additionally, we show that when using multimodal data, our procedure can be used to identify genes whose expression reflects alternative notions of similarity between cells, such as physical proximity in a tissue or clonal relatedness in a cell lineage tree. In this manner, we demonstrate that while our method, calledHotspot, is capable of identifying genes that reflect nuanced transcriptional variability between T helper cells, it can also identify spatially-dependent patterns of gene expression in the cerebellum as well as developmentally-heritable expression signatures during embryogenesis.
Spectral finite element method for wave propagation analysis in smart composite beams containing delamination
Authors: Nanda Namita
Published: February 2020

Purpose

The purpose of the study is to present a frequency domain spectral finite element model (SFEM) based on fast Fourier transform (FFT) for wave propagation analysis of smart laminated composite beams with embedded delamination. For generating and sensing high-frequency elastic waves in composite beams, piezoelectric materials such as lead zirconate titanate (PZT) are used because they can act as both actuators and sensors. The present model is used to investigate the effects of parametric variation of delamination configuration on the propagation of fundamental anti-symmetric wave mode in piezoelectric composite beams.

Design/methodology/approach

The spectral element is derived from the exact solution of the governing equation of motion in frequency domain, obtained through fast Fourier transformation of the time domain equation. The beam is divided into two sublaminates (delamination region) and two base laminates (integral regions). The delamination region is modeled by assuming constant and continuous cross-sectional rotation at the interfaces between the base laminate and sublaminates. The governing differential equation of motion for delaminated composite beam with piezoelectric lamina is obtained using Hamilton’s principle by introducing an electrical potential function.

Findings

A detailed study of the wave response at the sensor shows that the A0 mode can be used for delamination detection in a wide region and is more suitable for detecting small delamination. It is observed that the amplitude and time of arrival of the reflected A0 wave from a delamination are strongly dependent on the size, position of the delamination and the stacking sequence. The degraded material properties because of the loss of stiffness and density in damaged area differently alter the S0 and A0 wave response and the group speed. The present method provides a potential technique for researchers to accurately model delaminations in piezoelectric composite beam structures. The delamination position can be identified if the time of flight of a reflected wave from delamination and the wave propagation speed of A0 (or S0) mode is known.

Originality/value

Spectral finite element modeling of delaminated composite beams with piezoelectric layers has not been reported in the literature yet. The spectral element developed is validated by comparing the present results with those available in the literature. The spectral element developed is then used to investigate the wave propagation characteristics and interaction with delamination in the piezoelectric composite beam.
Assessing social media accessibility: the case of the Rock in Rio Lisboa music festival
Authors: Dinis Maria Gorete , Eusébio Celeste , Breda Zélia
Published: February 2020

Purpose

This paper aims to present a framework to analyse whether information published on social media is accessible for people with disabilities (PwD), namely, visual and hearing disabilities, with an application to a music festival.

Design/methodology/approach

The methodology used in this exploratory study consists of establishing a recommended framework to assess social media accessibility for PwD, especially for people with visual and hearing disabilities (PwVHD), and analyse, through an observation grid, if the information published on the official pages of the “Rock in Rio Lisboa” music festival on Facebook, Instagram, Twitter and YouTube is accessible for this target audience.

Findings

The results indicate that, although the Rock in Rio Lisboa music festival is promoted as a festival for all, posts on social media are not accessible for people with visual and/or hearing disabilities and do not meet most of the defined parameters established in the proposed assessment framework.

Originality/value

Social media accessibility has not been analysed in previous research in the tourism context. This paper aims to fill in the void by establishing criteria and parameters that can serve as a basis for a framework for accessibility assessment in social media for PwVHD.
Understanding the paradigm shift in maritime education
Authors: Simmons Erica , McLean Grace
Published: February 2020

Purpose

The purpose of this paper is to examine the changes that will impact learners and learning in the Fourth Industrial Revolution and provide recommendations for transforming education to meet the needs of the maritime industry.

Design/methodology/approach

The paper reviews the definition of the Fourth Industrial Revolution and the changes that have occurred in industry as a result. It looks at key Fourth Industrial Revolution technologies and its impacts on the maritime industry. It then presents some strategies for how the maritime education sector can begin to address the paradigm shifts that will be needed to transform education so as to focus on the advantages that can be derived from the Fourth Industrial Revolution.

Findings

Rapid technological advances are transforming the process of education around the world and will continue to disrupt not only the education sector but entire industries – education being only one of them. The maritime sector has some specific technologies that will drive digital transformation of business models. Maritime educational institutions around the world will need to be prepared to respond rapidly to this paradigm change and provide the skilled labour the industry will require to remain competitive.

Research limitations/implications

While the technologies that are impacting the Fourth Industrial Revolution have clearly been identified, the education sector still needs practical applications and integration into curriculum and learning to truly embrace the opportunities for the development of workforce competencies in this new age.

Practical implications

The maritime education sector must now start implementing strategies to expose students to new Fourth Industrial Revolution technologies such as artificial intelligence, machine learning, robotics, blockchain and automation technology and how they are changing the future of work. A new shift in the conscious application of these game-changing technologies will be required, and examples of integration are discussed as a starting point for building a long-term plan.

Social implications

The development of the human capital needed in the Fourth Industrial Revolution must begin now, and it presents challenges to those in the maritime education sector. It, therefore, requires that a digital transformation strategy is in place to deliver the specialized skills and new knowledge workers will need in the future.

Originality/value

This paper discusses the disruption that the Fourth Industrial Revolution technologies will bring to maritime education. One of the findings demonstrates that it clear that it is no longer competitive to ignore the disruption that is happening, and action is needed now.
The integration of automation and artificial intelligence into the logistics sector
Authors: Foster Marshalee N. , Rhoden Stephen L.N.H.
Published: February 2020

Purpose

Artificial intelligence (AI) and automation are technologies that make a global impact by optimizing manual and time-intensive processes using data analytics and robotics, thus making the task more efficient, effective and less time-consuming. This is represented in the cyber-physical context, in which humans and technologies are allowed to coexist and learn from each other.

Design/methodology/approach

The logistics and supply chain sector consists of numerous partners and stakeholders, and despite the limited inclusion of automation and AI within the sector, there are still many manual and repetitive tasks.

Findings

Stakeholders in the logistics and supply chain sector are creating awareness and slowly implementing AI and automation within their operations. The majority of shipping and logistics is done through the maritime sector, and this is expected to increase in line with the world’s population.

Research limitations/implications

Research was limited to Jamaica and a few other countries in the Caribbean. Broadening the scope to include other regional shipping and logistics industry stakeholders would be helpful.

Practical implications

The removal of sometimes mundane and even more complex manual processes in the logistics supply chain will give rise to more efficiencies and possibly increased revenue.

Social implications

Creating awareness in the Caribbean of international trends is a challenge. Empowering people to use automation and AI for the mitigation and adaptation of climate change and other disasters is yet to be fully realized. However, those who took part in the study did show a significant inclination toward the use of automation and AI in their every-day lives.

Originality/value

The purpose of this paper is to examine statistical data on the understanding of automation and AI within education, the port authority and major operators in the shipping and logistics sector throughout the Caribbean.
Prospective trial for the clinical efficacy of anogenital skin care with miconazole nitrate‐containing soap for diaper candidiasis
Authors: Takahashi Hidenori , Oyama Noritaka , Amamoto Masaya , Torii Tomoko , Matsuo Tomoko , Hasegawa Minoru
Published: February 2020

Anogenital skin care for the elderly remains an umbrella term concerning protective and non‐interventional regimens, particularly for ordinary diaper users. Our recent investigation has demonstrated the preventive effect of daily anogenital washing with miconazole nitrate‐containing soap to the development of diaper candidiasis. We extended this work to cover our hypothesis as to whether the miconazole soap has a therapeutic benefit in genital candidiasis. The study outline includes: (i) the enrollment of 21 bedridden inpatients (84 ± 9 years; eight men and 13 women) who were diagnosed clinically and mycologically with genital candidiasis, and who had never received topical and/or systemic antifungal agents; (ii) administration of anogenital washing with 0.75% miconazole‐containing soap once daily for 4 weeks; and (iii) assessment of clinical symptoms and detection of Candida materials by culture and microscopic examination. As assessed by clinical symptom scoring for incontinence‐associated dermatitis (IAD), the ratio of patients with severe to moderate symptoms dramatically decreased by 2 weeks and 10 of 21 patients became symptom‐free at 4 weeks. The IAD clinical severity score was significantly decreased at 4 weeks. Compared with the baseline positivity, both microscopic and cultured Candida‐positive rates were significantly decreased at 4 weeks after washing. All culture‐detected fungi were Candida albicans. Severe adverse events did not occur in all participants. Individual medical and risk factors had no significant correlation with clinical severity and duration of candidiasis on variance analysis. In conclusion, topical washing with miconazole soap is a safe and reliable non‐medical approach for soothing diaper‐associated genital candidiasis in bedridden inpatients in whom it is difficult to perform prompt medical examination.
Tumor volume and sphericity as predictors of local control after stereotactic radiosurgery for limited number (1‐4) brain metastases from nonsmall cell lung cancer
Authors: Ko Peter Hansoo , Kim Hun Jung , Lee Jeong Shim , Kim Woo Chul
Published: February 2020

Aim

This study aims to evaluate the usage of brain metastases (BM) tumor volume and sphericity as prognostic factors in local control (LC) after stereotactic radiosurgery (SRS) for limited number (1‐4) BM from nonsmall cell lung cancer (NSCLC).

Methods

We retrospectively reviewed 80 patients, with 141 BM, who were treated with SRS from 2012 to 2017. Local failure was defined as an increase in lesion size after SRS. LC and overall survival (OS) were estimated using Kaplan–Meier method. The Cox proportional hazards model was used for univariate and multivariate analysis.

Results

The median clinical and radiographic follow‐up was 11.2 and 9.0 months, respectively. The median BM tumor volume was 0.31 cm3 (0.01‐21.64 cm3) and the median tumor sphericity was 0.76 (0.39‐0.95). The median LC of the entire cohort was 28.8 months. LC rate at last follow‐up was achieved in 84.4% of patients (35.5% CR, 35.5% PR, and 13.5% SD). LC was 83.8% at 1 year and 56.3% at 2 years. On multivariate analysis, only sphericity (P < .001) and volume (P = .004) were found to be a strong predictor for LC. The median OS of the entire cohort was 24.1 months. On multivariate analysis, only GPA score was found to be a predictor for OS.

Conclusion

BM tumor sphericity and volume were found to be strong predictors for LC. Tumor sphericity and volume should be taken into consideration when treating patients with BM and when designing future prospective studies and developing prognostic indices.
Gender differences and the correlates of violent behaviors among high school students in a post‐conflict area in Indonesia
Authors: Fausiah Fitri , Turnip Sherly Saragih , Hauff Edvard
Published: February 2020

Introduction

Adolescent violence is a public health problem worldwide. Studies show that challenging environments, such as poverty and war, increase the risk of adolescent violence. This paper aims to assess gender differences in violent behaviors among adolescents in a post‐conflict area in Indonesia. The other aim of this study is to investigate the correlates of adolescents' violent behaviors using the socio‐ecological framework.

Methods

This is a school‐based study involving 511 students from six randomly selected high schools in Kotamadya Ambon. Active and verbal violent behaviors and the potential correlates were measured and assessed using backward linear regression analyses.

Results

Boys were involved in more violent behaviors than girls. However, some of the boys and girls reported being involved in all types of violent behaviors. The most significant correlates of violent behaviors across genders were community violence exposure and some types of behavioral problems.

Discussion

This study highlighted the interconnectedness between community violence exposure and violent behaviors among adolescents living in a post‐conflict area. The study also emphasizes the association between problem behaviors and violent behaviors. The results demonstrate the importance of both reducing community violence exposure and identifying adolescents with behavioral problems in the prevention of violent behaviors.
Estrogen‐related receptor‐α promotes gallbladder cancer development by enhancing the transcription of Nectin‐4
Authors: Wang Lei , Yang MengMeng , Guo Xingmei , Yang Ziyi , Liu Shilei , Ji Yuan , Jin Huihan
Published: February 2020

Estrogen‐related receptor‐α (ERRα) is a nuclear receptor of transcription factor that binds to estrogen responsive elements and estrogen‐related responsive elements. Estrogen‐related receptor‐α is involved in metabolic processes and implicated in the progression and growth of several human malignancies. However, the biologic role and clinical significance of ERRα in gallbladder cancer (GBC) remains to be clarified. Here, we reported that ERRα protein expression was notably higher in GBC tissues than in cholecystitis tissues, and that the aberrantly higher ERRα expression was positively correlated with advanced TNM stage and indicated dismal prognosis of GBC (P < .01). In GBC cell lines NOZ and OCUG, the targeted depletion of ERRα retarded the growth and suppressed the migration and invasive capabilities of GBC cells, and inhibited epithelial‐mesenchymal transition by decreasing the expression of mesenchymal markers and elevating the expression of epithelial markers. Moreover, ERRα knockdown inhibited tumor growth in nude mice and led to decreased expression levels of Nectin‐4, p‐PI3K p85α, and p‐AKT. Overexpression of ERRα in the GBC‐SD cell line showed exactly the opposite effect. The targeted inhibition of Nectin‐4 antagonized GBC cell proliferation and invasion, which were induced by ERRα upregulation. Moreover, Nectin‐4 depletion inhibited the ERRα‐induced activation of the PI3K/AKT pathway. Chromatin immunoprecipitation analysis and dual‐luciferase reporter gene assays showed that ERRα enhanced the transcription of Nectin‐4 by binding to the promoter of Nectin‐4. In conclusion, our data indicated that ERRα could be a potential target for the genetic treatment of GBC.
Psychotropic drug initiation in patients diagnosed with chronic myeloid leukemia: a population‐based study in France
Authors: Gauthier Martin , Conte Cécile , Palmaro Aurore , Patras De Campaigno Emilie , De Barros Sandra , Huguet Françoise , Laurent Guy , Lapeyre‐Mestre Maryse , Despas Fabien
Published: February 2020

Psychotropic drugs (PD) are often used close to a cancer diagnosis and may be considered as a way of coping. We aimed to determine the incidence of anxiolytics, hypnotics, antidepressants, and antipsychotics initiation around a diagnosis of chronic myelogenous leukemia (CML). Population‐based cohort: Data were extracted from Systeme National des données de Santé (SNDS, the French health insurance database) at the regional level (Midi‐Pyrenees area, 2.9 million inhabitants). All newly diagnosed patients treated by a CML tyrosine kinase inhibitor (TKI) between 10/01/2011 and 04/01/2014 were included. Pre‐CML (9 months before to 3 months before first TKI prescription—F‐TKI) and CML (3 months before to 9 months after F‐TKI) phases were defined. The main evaluation criterion was the initiation of PD during CML phase. Determinants associated with this incident PD use were studied through a logistic regression model. We compared pre‐CML and CML healthcare consumption. The cohort included 103 patients (mean age of 60.8 years). PD initiation rate was 35.9%, anxiolytics being the most initiated PD (59.5%). Advanced age was associated with PD initiation (adjusted OR = 1.029, 95% CI = 1.001–1.056). The number of consultations during the pre‐CML phase and female gender tended to be associated with increased risk of PD initiation in univariate analysis. For PD initiators, healthcare consumption was greater in CML but not in pre‐CML phase. PD initiation is a frequent finding around a CML diagnosis. Its risk increases with age. It could be a way to identify a subgroup with higher healthcare consumption.
Effect of routine dental attendance on child oral health‐related quality of life: A cohort study
Authors: Menegazzo Gabriele Rissotto , Knorst Jessica Klöckner , Emmanuelli Bruno , Mendes Fausto Medeiros , Ardenghi Diego Machado , Ardenghi Thiago Machado
Published: February 2020

Background

There is an improvement in oral health status among people who receive preventive dental care during their lifetime, highlighting the possible effect in resolving oral health problems and consequently oral health‐related quality of life (OHRQoL).

Aim

Assessed the effect of routine dental attendance on child OHRQoL.

Design

This cohort study used baseline data from 639 preschoolers from 2010. After 7 years, 449 children were re‐examined (70.3%). Mothers of the children completed a questionnaire collecting data on the pattern of use of dental services. Children were classified as adhering to long‐term routine dental attendance according to their pattern of use (routine vs curative) in the baseline and in follow‐up. The child OHRQoL was assessed through the Child Perception Questionnaire (CPQ8‐10). The association between routine dental attendance and child OHRQoL was assessed using multilevel Poisson regression models.

Results

The proportion of participants who reported the worst CPQ8‐10 scores were higher among those who, at some point in their life, experienced a curative dental attendance. Also, the mean CPQ8‐10 was two times higher for non‐routine dental attendance.

Conclusion

The findings showed that there is an impact of long‐term routine attendance on child OHRQoL. This is important for tackling oral health iniquities.