bluuebunny/crossref_metadata_2025 huggingface dataset:
Consonant age of acquisition effects are robust in children's nonword repetition performance
Authors: MOORE MICHELLE W.
Published: April 2018

The underlying processes of nonword repetition (NWR) have been studied extensively in both typical and atypical development. Most of the research examining long-term memory effects on NWR has focused on lexical and sublexical variables that can only be computed relative to the lexicon of a specific language (e.g., phonotactic probability). Sublexical variables that can be defined without reference to the lexicon (e.g., consonant age of acquisition; CAoA) have received little attention, although recent work has shown a CAoA effect on NWR in young adults by measuring performance differences when the stimuli comprise consonants acquired later versus earlier in speech development. The purpose of this study was to identify whether this sublexical effect occurs earlier in development. Thirty-one typically developing first and second graders completed NWR, nonword reading, and auditory lexical decision tasks. Nonword accuracy and word–nonword discriminability were consistently lower for items comprising later versus earlier acquired phonemes, even after controlling for vocabulary knowledge, but there were no differences in speed measures. Patterns of performance were similar to the CAoA effects observed in young adults from previous work. Results indicate that the sensitivity of NWR performance to these sublexical long-term memory effects occurs in childhood and reflects adultlike patterns of performance.
Joint Kinematic and Feature Tracking of Ships with Satellite Electronic Information
Authors: Liu Yong , Yao Libo , Xiong Wei , Zhou Zhimin
Published: April 2018

To track multiple ships and estimate the feature parameters of multiple emitters on board using electronic intelligence satellites under clutter interference, a long and random revisit time, and other complex conditions, a novel tracking algorithm using both kinematic (position and velocity) and feature information based on an improved Multiple Hypothesis Tracking (MHT) approach is proposed in this paper. Firstly, the characteristics of multi-ship tracking with multiple emitters using satellite electronic information are analysed, and a new model of an emitter is built as an extended target in geographical coordinates. Secondly, a pre-processing of measurements is utilised via hierarchical clustering using the location and feature information of emitters. Thirdly, feature information is incorporated into the MHT framework using Jensen-Shannon divergence distance and fuzzy C-means clustering to calculate track scores. Finally, we present the prediction and update of target states, especially the update of feature parameters, to realise joint kinematic and feature tracking of ships. The results of the simulation show that the proposed method has much better tracking performance than the standard MHT algorithm.
Enhancing Navigator Competence by Demonstrating Maritime Cyber Security
Authors: Hareide Odd Sveinung , Jøsok Øyvind , Lund Mass Soldal , Ostnes Runar , Helkala Kirsi
Published: April 2018

As technology continues to develop, information and communication technology and operational technology on board ships are increasingly being networked, and more frequently connected to the Internet. The introduction of cyber systems changes the work environment with the aim of decreasing the workload for the navigator, but at the same time introduces more complexity and vulnerabilities that in turn may alter the competencies needed to perform safe and efficient navigation. Contemporary examples of how cyber-attacks can distort situational awareness and interfere with operations are needed to enhance the navigator's competence through increased system awareness. This paper demonstrates some of the possible attack vectors that a cyber-attack can present to a ship, as well as discussing the plausibility and consequences of such attacks. In this study we provide a practical example to better understand how one can demystify cyber threats in order to enhance the navigators' competence.
Spatially resolved texture and microstructure evolution of additively manufactured and gas gun deformed 304L stainless steel investigated by neutron diffraction and electron backscatter diffraction
Authors: Takajo S. , Brown D. W. , Clausen B. , Gray G. T. , Knapp C. M. , Martinez D. T. , Trujillo C. P. , Vogel S. C.
Published: April 2018

In this study, we report the characterization of a 304L stainless steel cylindrical projectile produced by additive manufacturing. The projectile was compressively deformed using a Taylor Anvil Gas Gun, leading to a huge strain gradient along the axis of the deformed cylinder. Spatially resolved neutron diffraction measurements on the HIgh Pressure Preferred Orientation time-of-flight diffractometer (HIPPO) and Spectrometer for Materials Research at Temperature and Stress diffractometer (SMARTS) beamlines at the Los Alamos Neutron Science CEnter (LANSCE) with Rietveld and single-peak analysis were used to quantitatively evaluate the volume fractions of the α, γ, and ε phases as well as residual strain and texture. The texture of the γ phase is consistent with uniaxial compression, while the α texture can be explained by the Kurdjumov–Sachs relationship from the γ texture after deformation. This indicates that the material first deformed in the γ phase and subsequently transformed at larger strains. The ε phase was only found in volumes close to the undeformed material with a texture connected to the γ texture by the Shoji–Nishiyama orientation relationship. This allows us to conclude that the ε phase occurs as an intermediate phase at lower strain, and is superseded by the α phase when strain increases further. We found a proportionality between the root-mean-squared microstrain of the γ phase, dominated by the dislocation density, with the α volume fraction, consistent with strain-induced martensite α formation. Knowledge of the sample volume with the ε phase from the neutron diffraction analysis allowed us to identify the ε phase by electron back scatter diffraction analysis, complementing the neutron diffraction analysis with characterization on the grain level.
Phenotypical resistance correlation networks for 10 non-typhoidalSalmonellasubpopulations in an active antimicrobial surveillance programme
Authors: Love W. J. , Zawack K. A. , Booth J. G. , Gröhn Y. T. , Lanzas C.
Published: April 2018

Antimicrobials play a critical role in treating cases of invasive non-typhoidal salmonellosis (iNTS) and other diseases, but efficacy is hindered by resistant pathogens. Selection for phenotypical resistance may occur via several mechanisms. The current study aims to identify correlations that would allow indirect selection of increased resistance to ceftriaxone, ciprofloxacin and azithromycin to improve antimicrobial stewardship. These are medically important antibiotics for treating iNTS, but these resistances persist in non-TyphiSalmonellaserotypes even though they are not licensed for use in US food animals. A set of 2875Salmonella entericaisolates collected from animal sources by the National Antimicrobial Resistance Monitoring System were stratified in to 10 subpopulations based on serotype and host species. Collateral resistances in each subpopulation were estimated as network models of minimum inhibitory concentration partial correlations. Ceftriaxone sensitivity was correlated with otherβ-lactam resistances, and less commonly resistances to tetracycline, trimethoprim-sulfamethoxazole or kanamycin. Azithromycin resistance was frequently correlated with chloramphenicol resistance. Indirect selection for ciprofloxacin resistance via collateral selection appears unlikely. Density of the ACSSuT subgraph resistance aligned well with the phenotypical frequency. The current study identifies several important resistances in iNTS serotypes and further research is needed to identify the causative genetic correlations.
Need for improved public health protection of young people wanting body piercing: evidence from a look-back exercise at a piercing and tattooing premises with poor hygiene practices, Wales (UK) 2015
Authors: Perry M. , Lewis H. , Thomas D. Rh. , Mason B. , Richardson G.
Published: April 2018

Following a cluster of serious pseudomonas skin infections linked to a body piercing and tattooing premises, a look-back exercise was carried out to offer clients a screen for blood-borne viruses. Of those attending for screening 72% (581/809) had a piercing procedure in the premises of interest: 94 (16%) were under 16 years of age at the time of screening. The most common site of piercing was ear (34%), followed by nose (27%), nipple (21%) and navel (21%). A small number (<5) tested positive for hepatitis B and C, with no evidence this was linked to the premises. However, 36% (211/581) of clients reported a skin infection associated with their piercing. Using data from client forms, 36% provided a false age. Those aged under 16 years (OR 4.5, 95% CI 2.7–7.7) and those receiving a piercing at an intimate site (OR 2.1, 95% CI 1.3–3.6) were more likely to provide a false age. The findings from this exercise were used to support the drafting of the Public Health (Wales) Bill which proposed better regulation of piercing premises and the need to provide proof of being 18 years of age or over before having a piercing of an intimate site.
Time-series analysis of tuberculosis from 2005 to 2017 in China
Authors: Wang H. , Tian C. W. , Wang W. M. , Luo X. M.
Published: April 2018

Seasonal autoregressive integrated moving average (SARIMA) has been used to model nationwide tuberculosis (TB) incidence in other countries. This study aimed to characterise monthly TB notification rate in China. Monthly TB notification rate from 2005 to 2017 was used. Time-series analysis was based on a SARIMA model and a hybrid model of SARIMA-generalised regression neural network (GRNN) model. A decreasing trend (3.17% per years, P < 0.01) and seasonal variation of TB notification rate were found from 2005 to 2016 in China, with a predominant peak in spring. A SARIMA model of ARIMA (0,1,1) (0,1,1)12 was identified. The mean error rate of the single SARIMA model and the SARIMA–GRNN combination model was 6.07% and 2.56%, and the determination coefficient was 0.73 and 0.94, respectively. The better performance of the SARIMA–GRNN combination model was further confirmed with the forecasting dataset (2017). TB is a seasonal disease in China, with a predominant peak in spring, and the trend of TB decreased by 3.17% per year. The SARIMA–GRNN model was more effective than the widely used SARIMA model at predicting TB incidence.
Spatiotemporal Variability of Barium in Arctic Sea‐Ice and Seawater
Authors: Hendry Katharine R. , Pyle Kimberley M. , Barney Butler G. , Cooper Adam , Fransson Agneta , Chierici Melissa , Leng Melanie J. , Meyer Amelie , Dodd Paul A.
Published: April 2018

Freshwater export from the Arctic is critical in determining the density of water at sites of North Atlantic deep water formation, which in turn influences the global flux of oceanic heat and nutrients. We need geochemical tracers and high‐resolution observations to refine our freshwater budgets and constrain models for future change. The use of seawater barium concentrations in the Arctic Ocean as a freshwater tracer relies on the conservative behavior of barium in seawater; while this has been shown to be an unreliable assumption in Arctic summers, there are a lack of studies observing seasonal progressions. Here, we present barium concentrations from seawater and sea‐ice collected during the Norwegian Young Sea ICE expedition from boreal winter into summer. We use other tracers (salinity, oxygen isotopes, and alkalinity) to reconstruct freshwater inputs and calculate a barium “deficit” that can be attributed to nonconservative processes. We locate a deficit in winter when biological production is low, which we attribute to uptake by barite formation associated with old organic matter or by internal sea‐ice processes. We also find a significant barium deficit during the early spring bloom, consistent with uptake into organic‐matter associated microenvironments. However, in summer, there no strong barium deficit near the surface, despite high biological production and organic carbon standing stocks, perhaps reflecting phytoplankton assemblage changes, and/or rapid internal cycling. Our findings challenge the assumptions surrounding the use of barium as an Arctic freshwater tracer, and highlight the need to improve our understanding of barium in sea‐ice environments.
Simulation of crop growth, time to maturity and yield by an improved sigmoidal model
Authors: Liu Jun-He , Yan Yan , Ali Abid , Yu Ming-Fu , Xu Qi-Jie , Shi Pei-Jian , Chen Lei
Published: April 2018

Models that accurately estimate maximum crop biomass to obtain a reliable forecast of yield are useful in crop improvement programs and aiding establishment of government policies, including those addressing issues of food security. Here, we present a new sigmoidal growth model (NSG) and compare its performance with the beta sigmoidal growth model (BSG) for capturing the growth trajectories of eight crop species. Results indicated that both the NSG and the BSG fitted all the growth datasets well (R2 > 0.98). However, the NSG performed better than the BSG based on the calculated value of Akaike’s information criterion (AIC). The NSG provided a consistent estimate for when maximum biomass occurred; this suggests that the parameters of the BSG may have less biological importance as compared to those in the NSG. In summary, the new sigmoidal growth model is superior to the beta sigmoidal growth model, which can be applied to capture the growth trajectory of various plant species regardless of the initial biomass values at the beginning of a growth period. Findings of this study will be helpful to understand the growth trajectory of different plant species regardless of their initial biomass values at the beginning of a growth period.
Towards reconstruction of the lost Late Bronze Age intra-caldera island of Santorini, Greece
Authors: Karátson Dávid , Gertisser Ralf , Telbisz Tamás , Vereb Viktor , Quidelleur Xavier , Druitt Timothy , Nomikou Paraskevi , Kósik Szabolcs
Published: April 2018

During the Late Bronze Age, the island of Santorini had a semi-closed caldera harbour inherited from the 22 ka Cape Riva Plinian eruption, and a central island referred to as ‘Pre-Kameni’ after the present-day Kameni Islands. Here, the size and age of the intracaldera island prior to the Late Bronze Age (Minoan) eruption are constrained using a photo-statistical method, complemented by granulometry and high-precision K-Ar dating. Furthermore, the topography of Late Bronze Age Santorini is reconstructed by creating a new digital elevation model (DEM). Pre-Kameni and other parts of Santorini were destroyed during the 3.6 ka Minoan eruption, and their fragments were incorporated as lithic clasts in the Minoan pyroclastic deposits. Photo-statistical analysis and granulometry of these lithics, differentiated by lithology, constrain the volume of Pre-Kameni to 2.2–2.5 km3. Applying the Cassignol-Gillot K-Ar dating technique to the most characteristic black glassy andesite lithics, we propose that the island started to grow at 20.2 ± 1.0 ka soon after the Cape Riva eruption. This implies a minimum long-term lava extrusion rate of ~0.13–0.14 km3/ky during the growth of Pre-Kameni.
Depletion of potassium and sodium in mantles of Mars, Moon and Vesta by core formation
Authors: Steenstra E. S. , Agmon N. , Berndt J. , Klemme S. , Matveev S. , van Westrenen W.
Published: April 2018

The depletions of potassium (K) and sodium (Na) in samples from planetary interiors have long been considered as primary evidence for their volatile behavior during planetary formation processes. Here, we use high-pressure experiments combined with laser ablation analyses to measure the sulfide-silicate and metal-silicate partitioning of K and Na at high pressure (P) – temperature (T) and find that their partitioning into metal strongly increases with temperature. Results indicate that the observed Vestan and Martian mantle K and Na depletions can reflect sequestration into their sulfur-rich cores in addition to their volatility during formation of Mars and Vesta. This suggests that alkali depletions are not affected solely by incomplete condensation or partial volatilization during planetary formation and differentiation, but additionally or even primarily reflect the thermal and chemical conditions during core formation. Core sequestration is also significant for the Moon, but lunar mantle depletions of K and Na cannot be reconciled by core formation only. This supports the hypothesis that measured isotopic fractionations of K in lunar samples represent incomplete condensation or extensive volatile loss during the Moon-forming giant impact.
Brachial-Ankle Pulse Wave Velocity is Associated with the Risk of New Carotid Plaque Formation: Data from a Chinese Community-based Cohort
Authors: Yang Yao , Fan Fangfang , Kou Minghao , Yang Ying , Cheng Guanliang , Jia Jia , Gao Lan , Zhou Zechen , Chen Dafang , Zhang Yan , Huo Yong
Published: April 2018

Artery stiffness is an independent marker for atherosclerotic cardiovascular diseases. However, whether the brachial-ankle pulse wave velocity (ba-PWV) is related to new carotid plaque formation is unresolved. This study aimed to investigate the association between baseline ba-PWV and new carotid plaque formation in a Chinese community-based population without carotid plaques at baseline. This study population consisted of a total of 738 participants from an atherosclerosis cohort in Beijing, China. After a mean 2.3-year follow-up, the incidence of carotid plaques were 21.2% and 36.5% in the groups with ba-PWV < 1,400 cm/s and ≥1,400 cm/s, respectively. Compared with baseline ba-PWV < 1,400 cm/s group, ba-PWV ≥ 1,400 cm/s group was significantly associated with the incidence of new carotid plaque formation (odds ratio [OR] = 2.14, 95% CI: 1.50–3.03, P < 0.01), even after adjusting for common risk factors (OR = 1.52, 95% CI: 1.02–2.25, P = 0.04). Furthermore, there was a strong relationship between baseline ba-PWV and carotid plaque formation in subjects with ba-PWV < 1,400 cm/s, but no such relationship was found in subjects with baseline ba-PWV ≥ 1,400 cm/s. In conclusion, this study suggests that baseline ba-PWV is independently associated with the risk of carotid plaque formation in a Chinese community-based population.
Ca2+ imaging and gene expression profiling of Lonicera Confusa in response to calcium-rich environment
Authors: Jin Wenwen , Long Yan , Fu Chunhua , Zhang Libin , Xiang Jun , Wang Baoshan , Li Maoteng
Published: April 2018

As a medicinal plant widely planted in southwest karst of China, the study of adaptation mechanisms ofLonicera confusa, especially to karst calcium-rich environment, can provide important theoretical basis for repairing desertification by genetic engineering. In this study, the Ca2+imaging in the leaves ofL. confusawas explored by LSCM (Laser Scanning Confocal Microscopy) and TEM (Transmission Electron Microscopy), which revealed that the calcium could be transported to gland, epidermal hair and stoma in the leaves ofL. confusain high-Ca2+environment. In addition, we simulated the growth environment ofL. confusaand identified DEGs (Differentially Expressed Genes) under different Ca2+concentrations by RNA sequencing. Further analysis showed that these DEGs were assigned with some important biological processes. Furthermore, a complex protein-protein interaction network among DEGs inL. Confusawas constructed and some important regulatory genes and transcription factors were identified. Taken together, this study displayed the Ca2+transport and the accumulation of Ca2+channels and pools inL. Confusawith high-Ca2+treatment. Moreover, RNA sequencing provided a global picture of differential gene expression patterns inL. Confusawith high-Ca2+treatment, which will help to reveal the molecular mechanism of the adaptation ofL. confusato high-Ca2+environment in the future.
An engineered nanocomposite for sensitive and selective detection of mercury in environmental water samples
Authors: Abdullah Ibrahim H. , Ahmed Nashaat , Mohamed Mona A. , Ragab Fawzy M. A. , Abdel-Wareth Marwa T. A. , Allam Nageh K.
Published: April 2018

We report on a novel carbon-based nanocomposite made of reduced graphene oxide/titania nanotubes (RGO/TNT) with excellent conductivity and absorptivity for the sensitive electrochemical determination of Hg(ii) as a water pollutant.
Coumarin-diene photoswitches for rapid and efficient isomerization with visible light
Authors: Richers Matthew T. , Tran Dinh Du , Wachtveitl Josef , Ellis-Davies Graham C. R.
Published: April 2018

Coumarin-dienyl chromophores undergo rapid, fatigue-resistant bi-directional photoswitching with visible light.
Photoactivation of imatinib–antibody conjugate using low-energy visible light from Ru(ii)-polypyridyl cages
Authors: Rohrabaugh Thomas N. , Rohrabaugh Ashley M. , Kodanko Jeremy J. , White Jessica K. , Turro Claudia
Published: April 2018

Ru(ii)-polypyridyl cages with sterically bulky bidentate ligands provide efficient photochemical release of the anticancer drug imatinib using low energy visible light, imparting spatiotemporal control over drug bioavailability.
Argentate(i) and (iii) complexes as intermediates in silver-mediated cross-coupling reactions
Authors: Weske Sebastian , Hardin Richard A. , Auth Thomas , O’Hair Richard A. J. , Koszinowski Konrad , Ogle Craig A.
Published: April 2018

Silver-mediated cross-coupling reactions proceed via anionic ate complexes, which have been characterized by a combination of NMR spectroscopy, ESI mass spectrometry, and quantum-chemical calculations.
Electronic effects and fundamental physics studied in molecular interfaces
Authors: Pope Thomas , Du Shixuan , Gao Hong-Jun , Hofer Werner A.
Published: April 2018

Scanning probe instruments in conjunction with a very low temperature environment have revolutionized the ability of building, functionalizing, and analysing two dimensional interfaces in the last twenty years.
Late-stage deuteration of13C-enriched substrates forT1prolongation in hyperpolarized13C MRI
Authors: Taglang Céline , Korenchan David E. , von Morze Cornelius , Yu Justin , Najac Chloé , Wang Sinan , Blecha Joseph E. , Subramaniam Sukumar , Bok Robert , VanBrocklin Henry F. , Vigneron Daniel B. , Ronen Sabrina M. , Sriram Renuka , Kurhanewicz John , Wilson David M. , Flavell Robert R.
Published: April 2018

Deuteration on13C-enriched substrates led to increases inT1, yielding improvements in imaging parameters.
Plasmonically enhanced electromotive force of narrow bandgap PbS QD-based photovoltaics
Authors: Li Xiaowei , McNaughter Paul D. , O'Brien Paul , Minamimoto Hiro , Murakoshi Kei
Published: April 2018

Promoted photocurrent generation results in an improved electromotive force by combining MEG-effective PbS QDs with LSPR-active Au nanoparticles.
Anomalous diffusion of water molecules at grain boundaries in ice Ih
Authors: Moreira Pedro Augusto Franco Pinheiro , Veiga Roberto Gomes de Aguiar , Ribeiro Ingrid de Almeida , Freitas Rodrigo , Helfferich Julian , de Koning Maurice
Published: April 2018

First-principles and classical molecular dynamics simulations show that diffusion of water molecules at pre-melted grain boundaries in ice is glassy-like, showing sub-diffusive behavior.
On the relationship between the structural and volumetric properties of solvated metal ions inO-donor solvents using new structural data in amide solvents
Authors: Lundberg Daniel , Warmińska Dorota , Fuchs Anna , Persson Ingmar
Published: April 2018

The relationship between the structural and volumetric properties of ions in solvents with different physico-chemical properties has been studied for 19 cations and six anions in six solvents.
Synthesis, characterisation and thermal properties of Sn(ii) pyrrolide complexes
Authors: Parish James D. , Snook Michael W. , Johnson Andrew L. , Kociok-Köhn Gabriele
Published: April 2018

A series of Sn(ii) pyrrolide complexes have been synthesised, characterised and their thermal properties assessed for their potential application in the MOCVD and ALD of SnO thin films.
Photoluminescent carbon dots based on a rare 3D inorganic–organic hybrid cadmium borate crystal
Authors: Zhou Kang , Zhang Wen-Jin , Luo Yuan-Zhang , Pan Chun-Yang
Published: April 2018

A 3D inorganic–organic hybridized skeleton cadmium borate [Cden][B5O8(OH)] (1) (en = ethylenediamine) has been solvothermally synthesized. By calcining it, specific shape carbon dots (C-dots) with abundant free radicals were observed. In addition, C-dots in the ethanol phase exhibited variable photoluminescence and showed a special effect to Cr3+/Cs+ ions and CdSe/ZnS, CsPbBr3 quantum dots.
g-C3N4 supported metal (Pd, Ag, Pt) catalysts for hydrogen-production from formic acid
Authors: Liu Xiaotong , Su Penghe , Chen Ya , Zhu Baolin , Zhang Shoumin , Huang Weiping
Published: April 2018

Pd/g-C3N4 with d–π interaction between Pd NPs and g-C3N4 with a π-conjugated system shows high catalytic activity in the dehydrogenation of FA.
New Pd/Pt(ii) complexes as unsymmetrical ylide-based chemotherapeutic agents: synthesis, characterization, biological activity, electrochemical, and X-ray studies
Authors: Sabounchei Seyyed Javad , Badpa Khadijeh , Nematollahi Davood , Sharafi-kolkeshvandi Mahnaz , Hosseinzadeh Leila , Karamian Roya , Ghasemlou Fatemeh , Gable Robert W.
Published: April 2018

New P,C-coordinated Pd/Pt-complexes were characterized successfully and the cytotoxic studies showed that they can be used as non-toxic labels for cellular imaging.
Nitrogen doped high quality CVD grown graphene as a fast responding NO2gas sensor
Authors: Srivastava Shubhda , Kashyap Pradeep Kumar , Singh Vidyanand , Senguttuvan T. D. , Gupta Bipin Kumar
Published: April 2018

Nitrogen doped high quality CVD grown graphene is demonstrated for application in a high performance NO2gas sensor.
Novel phenanthroimidazole-based blue AIEgens: reversible mechanochromism, bipolar transporting properties, and electroluminescence
Authors: Wang Zhong-Yi , Zhao Jue-Wen , Li Peng , Feng Tong , Wang Wen-Jian , Tao Si-Lu , Tong Qing-Xiao
Published: April 2018

Multifunctional materials are crucial and have promising applications in a wide range of organic electronics.
Selective nickel-catalyzed dehydrogenative–decarboxylative formylation of indoles with glyoxylic acid
Authors: Yin Zhiping , Wang Zechao , Wu Xiao-Feng
Published: April 2018

Herein we present a new strategy for the dehydrogenative–decarboxylative coupling of indoles with glyoxylic acid.
Glassy worm-like micelles in solvent and shear mediated shape transitions
Authors: Chakraborty Kaushik , Vijayan Kandaswamy , Brown Andre E. X. , Discher Dennis E. , Loverde Sharon M.
Published: April 2018

Solvent effect on the shape of worm-like glassy micelles as characterized both experimentally and with simulation.
Small vessels, dementia and chronic diseases – molecular mechanisms and pathophysiology
Authors: Horsburgh Karen , Wardlaw Joanna M. , van Agtmael Tom , Allan Stuart M. , Ashford Mike L.J. , Bath Philip M. , Brown Rosalind , Berwick Jason , Cader M. Zameel , Carare Roxana O. , Davis John B. , Duncombe Jessica , Farr Tracy D. , Fowler Jill H. , Goense Jozien , Granata Alessandra , Hall Catherine N. , Hainsworth Atticus H. , Harvey Adam , Hawkes Cheryl A. , Joutel Anne , Kalaria Rajesh N. , Kehoe Patrick G. , Lawrence Catherine B. , Lockhart Andy , Love Seth , Macleod Malcolm R. , Macrae I. Mhairi , Markus Hugh S. , McCabe Chris , McColl Barry W. , Meakin Paul J. , Miller Alyson , Nedergaard Maiken , O'Sullivan Michael , Quinn Terry J. , Rajani Rikesh , Saksida Lisa M. , Smith Colin , Smith Kenneth J. , Touyz Rhian M. , Trueman Rebecca C. , Wang Tao , Williams Anna , Williams Steven C.R. , Work Lorraine M.
Published: April 2018

Cerebral small vessel disease (SVD) is a major contributor to stroke, cognitive impairment and dementia with limited therapeutic interventions. There is a critical need to provide mechanistic insight and improve translation between pre-clinical research and the clinic. A 2-day workshop was held which brought together experts from several disciplines in cerebrovascular disease, dementia and cardiovascular biology, to highlight current advances in these fields, explore synergies and scope for development. These proceedings provide a summary of key talks at the workshop with a particular focus on animal models of cerebral vascular disease and dementia, mechanisms and approaches to improve translation. The outcomes of discussion groups on related themes to identify the gaps in knowledge and requirements to advance knowledge are summarized.
Optimal extinction measurements
Authors: Lombardi Marco
Published: April 2018

In this paper we present XNICER, an optimized multi-band extinction technique based on the extreme deconvolution of the intrinsic colors of objects observed through a molecular cloud. XNICER follows a rigorous statistical approach and provides the full Bayesian inference of the extinction for each observed object. Photometric errors in both the training control field and in the science field are properly taken into account. XNICER improves over the known extinction methods and is computationally fast enough to be used on large datasets of objects. Our tests and simulations show that this method is able to reduce the noise associated with extinction measurements by a factor 2 with respect to the previous NICER algorithm, and it has no evident bias even at high extinctions.
Dynamical evolution of C/2017 K2 PANSTARRS
Authors: Królikowska Małgorzata , Dybczyński Piotr A.
Published: April 2018

Context. The comet C/2017 K2 PANSTARRS drew attention to its activity at the time of its discovery in May 2017 when it was about 16 au from the Sun. This Oort spike comet will approach its perihelion in December 2022, and the question about its dynamical past is an important issue to explore.

Aims. In order to answer the question of whether C/2017 K2 is a dynamically old or new comet it is necessary to obtain its precise osculating orbit, its original orbit, and propagate its motion backwards in time to the previous perihelion. Knowledge of the previous perihelion distance is necessary to distinguish between these two groups of the Oort spike comets. We have studied the dynamical evolution of C/2017 K2 to the previous perihelion (backward calculations for about 3–4 Myr) as well as to the future (forward calculations for about 0.033 Myr) using the swarm of virtual comets (VCs) constructed from a nominal osculating orbit of this comet which we determined here using all positional measurements available at the moment. Outside the planetary system both Galactic and stellar perturbations were taken into account.

Results. We derive that C/2017 K2 is a dynamically old Oort spike comet (1/aprev = (48.7 ± 7.9) × 10−6 au−1) with the previous perihelion distance below 10 au for 97% of VCs (nominal qprev = 3.77 au). According to the present data this comet will be perturbed into a more tightly bound orbit after passing the planetary zone (1/afut = (1140.4 ± 8.0) × 10−6 au−1, qfut = 1.79336 ± 0.00006 au) provided that non-gravitational effects will not change the orbit significantly.

Conclusions. C/2017 K2 has already visited our planetary zone during its previous perihelion passage. Thus, it is almost certainly a dynamically old Oort spike comet. The future orbital solution of this comet is formally very precise, however, it is much less definitive since the presented analysis is based on pre-perihelion data taken at very large heliocentric distances (23.7–14.6 au from the Sun), and this comet can experience a significant non-gravitational perturbation during the upcoming perihelion passage in 2022.
Stenting for Advanced Esophageal Carcinoma
Authors: Kim Kun , Park Jung-Hoon , Shin Ji
Published: April 2018

Esophageal cancer is the eighth most common malignancy and the sixth leading cause of cancer-related deaths worldwide. Most patients with esophageal cancer are identified at an advanced stage of disease. Less than 20% of patients are candidates for curable surgical resection. Self-expandable metallic stents (SEMSs) have recently been used for the palliation of incurable esophageal cancer. Since their use was first reported in the late 1970s, stents have evolved rapidly from rigid plastic tubes to flexible SEMSs. This review covers various aspects of SEMS placement for advanced esophageal cancer and discusses multiple types of SEMSs, considerations in stent placement, complications, and recently developed radiation-emitting stents.
Broadband incoherent four-wave mixing and 27 dB idler conversion efficiency using ultra-silicon rich nitride devices
Authors: Choi J. W. , Sohn B.-U. , Chen G. F. R. , Ng D. K. T. , Tan D. T. H.
Published: April 2018

The generation of broadband light within the telecommunication band has been instrumental to the design and characterization of advanced optical devices and systems. In this paper, stimulated degenerate four-wave mixing of an ultra-silicon rich nitride waveguide is investigated using a pulsed pump at 1.555 μm and incoherent broadband sources emitting in the 1.65 μm wavelength region as a signal. The waveguide possesses a large nonlinear parameter of 330 W−1/m as well as anomalous dispersion, required for phase matched parametric processes. The broadband idler ranging from 1.43 μm to 1.52 μm is generated using a coupled peak power of 4.6 W, spanning ∼100 nm at the −20 dB level, which is sufficient to cover parts of the E- and S-bands. The spectral span of the generated idler also agrees well with the calculation based on the phase-matching condition governing degenerate four-wave mixing. Cascaded incoherent four-wave mixing is also observed. Using a supercontinuum pump spanning from 1.1 to 1.7 μm with a coupled peak power of 26 W, an idler spanning from 1.2 to 1.4 μm is generated, equivalent to an idler on/off conversion efficiency of 27 dB.
Actively tunable transverse waves in soft membrane-type acoustic metamaterials
Authors: Zhou Weijian , Wu Bin , Muhammad  , Du Qiujiao , Huang Guoliang , Lü Chaofeng , Chen Weiqiu
Published: April 2018

Membrane-type metamaterials have shown a fantastic capacity for manipulating acoustic waves in the low frequency range. They have the advantages of simple geometry, light weight, and active tunability. In general, these membrane-type metamaterials contain a rigid frame support, leading to a fixed configuration. However, in some instances, flexible and reconfigurable devices may be desirable. A soft membrane-type acoustic metamaterial that is highly flexible and controllable is designed here. Different from the previously designed membrane-type metamaterials, the stiff supporting frame is removed and the stiff mass at the center of each unit cell is replaced by the soft mass, realized by bonding fine metallic particles in the central region. In contrast to the previous studies, the propagation of elastic transverse waves in such a soft metamaterial is investigated by employing the plane wave expansion method. Both the Bragg scattering bandgaps and locally resonant bandgaps are found to coexist in the soft metamaterial. The influences of structural parameters and finite biaxial pre-stretch on the dynamic behavior of this soft metamaterial are carefully examined. It is shown that whether or not the wave propagation characteristics are sensitive to the finite deformation does not depend on the property and pre-stretch of the membrane. In addition, a broadband complete bandgap and a pseudo-gap formed by the combination of two extremely adjacent directional bandgaps are observed in the low-frequency range, and both can be controlled by the finite pre-stretch.
Plasma-surface interaction in negative hydrogen ion sources
Authors: Wada Motoi
Published: April 2018

A negative hydrogen ion source delivers more beam current when Cs is introduced to the discharge, but a continuous operation of the source reduces the beam current until more Cs is added to the source. This behavior can be explained by adsorption and ion induced desorption of Cs atoms on the plasma grid surface of the ion source. The interaction between the ion source plasma and the plasma grid surface of a negative hydrogen ion source is discussed in correlation to the Cs consumption of the ion source. The results show that operation with deuterium instead of hydrogen should require more Cs consumption and the presence of medium mass impurities as well as ions of the source wall materials in the arc discharge enlarges the Cs removal rate during an ion source discharge.
Determining the refractive index of particles using glare-point imaging technique
Authors: Meng Rui , Ge Baozhen , Lu Qieni , Yu Xiaoxue
Published: April 2018

A method of measuring the refractive index of a particle is presented from a glare-point image. The space of a doublet image of a particle can be determined with high accuracy by using auto-correlation and Gaussian interpolation, and then the refractive index is obtained from glare-point separation, and a factor that may influence the accuracy of glare-point separation is explored. Experiments are carried out for three different kinds of particles, including polystyrene latex particles, glass beads, and water droplets, whose measuring accuracy is improved by the data fitting method. The research results show that the method presented in this paper is feasible and beneficial to applications such as spray and atmospheric composition measurements.
On local and global aspects of the 1:4 resonance in the conservative cubic Hénon maps
Authors: Gonchenko M. , Gonchenko S. V. , Ovsyannikov I. , Vieiro A.
Published: April 2018

We study the 1:4 resonance for the conservative cubic Hénon maps C± with positive and negative cubic terms. These maps show up different bifurcation structures both for fixed points with eigenvalues ±i and for 4-periodic orbits. While for C–, the 1:4 resonance unfolding has the so-called Arnold degeneracy [the first Birkhoff twist coefficient equals (in absolute value) to the first resonant term coefficient], the map C+ has a different type of degeneracy because the resonant term can vanish. In the last case, non-symmetric points are created and destroyed at pitchfork bifurcations and, as a result of global bifurcations, the 1:4 resonant chain of islands rotates by π/4. For both maps, several bifurcations are detected and illustrated.
Fluid flow in a spiral microfluidic duct
Authors: Harding Brendan , Stokes Yvonne
Published: April 2018

We consider the steady, pressure driven flow of a viscous fluid through a microfluidic device having the geometry of a planar spiral duct with a slowly varying curvature and height smaller than width. For this problem, it is convenient to express the Navier–Stokes equations in terms of a non-orthogonal coordinate system. Then, after applying appropriate scalings, the leading order equations admit a relatively simple solution in the central region of the duct cross section. First-order corrections with respect to the duct curvature and aspect ratio parameters are also obtained for this region. Additional correction terms are needed to ensure that no slip and no penetration conditions are satisfied on the side walls. Our solutions allow for a top wall shape that varies with respect to the radial coordinate which allows us to study the flow in a variety of cross-sectional shapes, including trapezoidal-shaped ducts that have been studied experimentally. At leading order, the flow is found to depend on the local height and slope of the top wall within the central region. The solutions are compared with numerical approximations of a classical Dean flow and are found to be in good agreement for a small duct aspect ratio and a slowly varying and small curvature. We conclude that the slowly varying curvature typical of spiral microfluidic devices has a negligible impact on the flow in the sense that locally the flow does not differ significantly from the classical Dean flow through a duct having the same curvature.
Evaluating the potential energy landscape over single molecules at room temperature with lateral force microscopy
Authors: Weymouth Alfred J. , Riegel Elisabeth , Matencio Sonia , Giessibl Franz J.
Published: April 2018

One of the challenges of AFM, in contrast to STM, is that the measured signal includes both long-range and short-range components. The most accurate method for removing long-range components is to measure both on and off an adsorbate and to subtract the difference. This on-off method is challenging at room temperature due to thermal drift. By moving to a non-contact scheme in which the lateral component of the force interaction is probed, the measurement is dominated by short-range interactions. We use frequency-modulation lateral force microscopy to measure individual PTCDA molecules adsorbed on Ag/Si(111)-(3×3). By fitting the data to a model potential, we can extract the depth and width of the potential. When the tip is closer to the sample, a repulsive feature can be observed in the data.
Stereodynamics of Ne(3P2) reacting with Ar, Kr, Xe, and N2
Authors: Zou Junwen , Gordon Sean D. S. , Tanteri Silvia , Osterwalder Andreas
Published: April 2018

Stereodynamics experiments of Ne(3P2) reacting with Ar, Kr, Xe, and N2 leading to Penning and associative ionization have been performed in a crossed molecular beam apparatus. A curved magnetic hexapole was used to state-select and polarize Ne(3P2) atoms which were then oriented in a rotatable magnetic field and crossed with a beam of Ar, Kr, Xe, or N2. The ratio of associative to Penning ionization was recorded as a function of the magnetic field direction for collision energies between 320 cm−1 and 500 cm−1. Reactivities are obtained for individual states that differ only in Ω, the projection of the neon total angular momentum vector on the inter-particle axis. The results are rationalized on the basis of a model involving a long-range and a short-range reaction mechanism. Substantially lower probability for associative ionization was observed for N2, suggesting that predissociation plays a critical role in the overall reaction pathway.
Risky business: is pubic hair removal by women associated with body image and sexual health?
Authors: Grossman Stephanie L. , Annunziato Rachel A.
Published: April 2018

Background Body hair removal is a behaviour that has become normative among women in Westernised cultures, and is presented by the media as the feminine ideal, despite being painful and a potential cause of infection. Of concern, removal may be part of a more global pattern of appearance dissatisfaction and risky sexual behaviour. The aim of the present study was to examine the relationships among pubic hair removal, body image and sexual health indicators. Methods: Women (n = 264; Mage = 33.82, s.d. = 11.13, range = 18–66) completed self-report questionnaires assessing these constructs, including an assessment of body hair removal practices. Results: Greater appearance concerns (as measured by thin-ideal internalisation, appearance investment and self-objectification) and sexual health indicators (i.e. less condom use self-efficacy when a partner disapproves of condom use) all predicted greater importance of reasons for pubic hair removal (R2 = 0.315, F(8184) = 9.97, P < 0.001), controlling for age groups. Additionally, women who removed a greater amount of hair reported more thin-ideal internalisation and appearance investment than those who removed less hair. Conclusions: Women who express stronger reasoning for pubic hair removal, and remove a larger amount of it, may endorse problematic beliefs and behaviours particularly related to appearance concerns. It is important for practitioners to consider this practice as distinct from grooming and to be aware of its association with a broader array of risky beliefs and behaviours that can compromise women’s well-being.
Slow and unsteady: growth of the Australian eastern long-necked turtle near the southern end of its natural range
Authors: Chessman Bruce C.
Published: April 2018

Knowledge of growth rates and maturation times of freshwater turtles is important in assessing population viability. I analysed growth of Australian eastern long-necked turtles (Chelodina longicollis) from individual capture–recapture records spanning periods of up to 17 years for a population in Gippsland, Victoria, close to the high-latitude end of the species’ natural range. Juvenile growth was rapid and similar among individuals but adult growth was usually slow, highly variable among individuals and erratic within individuals over time. In addition, asymptotic body lengths were disparate among individuals for both males and females. Von Bertalanffy growth models fitted separately to males plus unsexed juveniles and females plus unsexed juveniles performed better than logistic models but tended to underestimate growth rates for very small and very large turtles and overestimate growth for medium-sized individuals. Sexual maturity was estimated to be achieved at 10 years in males and 16 years in females, which is late compared with most estimates for other populations of C. longicollis and for other turtle species in south-eastern Australia. The high variability of individual growth in this population makes age estimation from body size unreliable beyond the first few years of life.
Escherichia colicultures maintain stable subpopulation structure during long-term evolution
Authors: Behringer Megan G. , Choi Brian I. , Miller Samuel F. , Doak Thomas G. , Karty Jonathan A. , Guo Wanfeng , Lynch Michael
Published: April 2018

Significance

Understanding how microbes adapt to novel environments is essential to understanding acute bacterial infection and long-term disease, as genetic architecture underlying the production and maintenance of genetic variation influences a population’s potential for adaptation. In this in-depth analysis of a highly replicatedEscherichia colilong-term evolution experiment, we observe rapid diversification into stable subpopulations in response to several environmental variables. This niche separation creates novel genetic backgrounds upon which new traits, such as differential nutrient utilization or antimicrobial resistance, can arise. The observed genetic changes, in a simple and tractable experimental system, mimic events known to occur during bacterial infections.
Structured networks support sparse traveling waves in rodent somatosensory cortex
Authors: Moldakarimov Samat , Bazhenov Maxim , Feldman Daniel E. , Sejnowski Terrence J.
Published: April 2018

Significance

The deflection of a single whisker activates neurons in the corresponding barrel of rodent somatosensory cortex, which is followed by a traveling wave of activity across the upper layer 2/3 (L2/3) of barrel cortex. There are many ways to generate traveling waves, but the model that we propose is the only one that is constrained by the data from the barrel cortex. We also explain the importance of traveling waves for encoding sensory stimuli in the barrel cortex and show how whisker stimulation induces horizontal propagation of activity within the barrel cortex with the observed sparse neural activity. Our theory contrasts the conventional theory of sensory processing, which assumes feedforward processing in hierarchically organized cortical networks.