bluuebunny/crossref_metadata_2025 huggingface dataset:
Supporting young children as digital citizens: The importance of shared understandings of technology to support integration in play‐based learning
Authors: Bittner Kelly , Highfield Kate , Hadley Fay
Published: September 2018

The ubiquity of technology in contemporary society positions it as a significant cultural tool in children’s lives. Definitions, conceptualisations and understandings of the relevance of technology are diverse which can hinder integration of technology in early learning settings. This paper presents findings from a doctoral research project that investigated Australian educator beliefs and practices in relation to technology integration within play‐based curriculums for children aged three to five years. The key findings presented relate to creating connections and shared conceptualisations of technology between educators, families and directors of early learning services. Shared understandings of the sociocultural relevance of diverse technological tools were found to facilitate technology integration in the curriculum. Rogoff’s (1995) three planes of analysis were utilised to identify and understand the interplay between the personal, interpersonal and community levels of sociocultural activity. A significant implication is identification of the need for professional discussion, professional learning and critical reflection opportunities to extend educator understandings of technology as socially, culturally, and pedagogically relevant for young children. Sharing this knowledge in collaborative partnerships between educators, families and management can support children’s development as digital citizens.
Girdin/GIV regulates collective cancer cell migration by controlling cell adhesion and cytoskeletal organization
Authors: Wang Xiaoze , Enomoto Atsushi , Weng Liang , Mizutani Yasuyuki , Abudureyimu Shaniya , Esaki Nobutoshi , Tsuyuki Yuta , Chen Chen , Mii Shinji , Asai Naoya , Haga Hisashi , Ishida Sumire , Yokota Kenji , Akiyama Masashi , Takahashi Masahide
Published: September 2018

Pathological observations show that cancer cells frequently invade the surrounding stroma in collective groups rather than through single cell migration. Here, we studied the role of the actin‐binding protein Girdin, a specific regulator of collective migration of neuroblasts in the brain, in collective cancer cell migration. We found that Girdin was essential for the collective migration of the skin cancer cell line A431 on collagen gels as well as their fibroblast‐led collective invasion in an organotypic culture model. We provide evidence that Girdin binds to β‐catenin that plays important roles in the Wnt signaling pathway and in E‐cadherin‐mediated cell‐cell adhesion. Girdin‐depleted cells displayed scattering and impaired E‐cadherin‐specific cell‐cell adhesion. Importantly, Girdin depletion led to impaired cytoskeletal association of the β‐catenin complex, which was accompanied by changes in the supracellular actin cytoskeletal organization of cancer cell cohorts on collagen gels. Although the underlying mechanism is unclear, this observation is consistent with the established role of the actin cytoskeletal system and cell‐cell adhesion in the collective behavior of cells. Finally, we showed the correlation of the expression of Girdin with that of the components of the E‐cadherin complex and the differentiation of human skin cancer. Collectively, our results suggest that Girdin is an important modulator of the collective behavior of cancer cells.
Submicroscopic Plasmodium infection during pregnancy is associated with reduced antibody levels to tetanus toxoid
Authors: Álvarez-Larrotta C , Agudelo OM , Duque Y , Gavina K , Yanow SK , Maestre A , Carmona-Fonseca J , Arango E
Published: September 2018

Submicroscopic Plasmodium infections in pregnancy are common in endemic areas, and it is important to understand the impact of these low-level infections. Asymptomatic, chronic infections are advantageous for parasite persistence, particularly in areas where the optimal eco-epidemiological conditions for parasite transmission fluctuate. In chronic infections, the persistence of the antigenic stimulus changes the expression of immune mediators and promotes constant immune regulation, including increases in regulatory T cell populations. These alterations of the immune system could compromise the response to routine vaccination. This study aimed to evaluate the effect of submicroscopic plasmodial infection with P. falciparum and P. vivax during pregnancy on the immune response to the tetanus toxoid vaccine in Colombian women. Expression of different cytokines and mediators of immune regulation and levels of anti-tetanus toxoid (TT) immunoglobulin (Ig)G were quantified in pregnant women with and without submicroscopic plasmodial infection. The anti-TT IgG levels were significantly lower in the infected group compared with the uninfected group. The expression of interferon (IFN)-γ, tumour necrosis factor (TNF) and forkhead box protein 3 (FoxP3) was significantly higher in the infected group, while the expression of cytotoxic T lymphocyte antigen 4 (CTLA-4) and transforming growth factor (TGF)-β was lower in the group of infected. In conclusion, submicroscopic Plasmodium infection altered the development of the immune response to the TT vaccine in Colombian pregnant women. The impact of Plasmodium infections on the immune regulatory pathways warrants further exploration.
Superpixel Generation by Agglomerative Clustering With Quadratic Error Minimization
Authors: Dong Xiao , Chen Zhonggui , Yao Junfeng , Guo Xiaohu
Published: September 2018

Superpixel segmentation is a popular image pre‐processing technique in many computer vision applications. In this paper, we present a novel superpixel generation algorithm by agglomerative clustering with quadratic error minimization. We use a quadratic error metric (QEM) to measure the difference of spatial compactness and colour homogeneity between superpixels. Based on the quadratic function, we propose a bottom‐up greedy clustering algorithm to obtain higher quality superpixel segmentation. There are two steps in our algorithm: merging and swapping. First, we calculate the merging cost of two superpixels and iteratively merge the pair with the minimum cost until the termination condition is satisfied. Then, we optimize the boundary of superpixels by swapping pixels according to their swapping cost to improve the compactness. Due to the quadratic nature of the energy function, each of these atomic operations has only O(1) time complexity. We compare the new method with other state‐of‐the‐art superpixel generation algorithms on two datasets, and our algorithm demonstrates superior performance.
Education disparities in young people with and without neurodisabilities
Authors: Sentenac Mariane , Lach Lucyna M , Gariepy Genevieve , Elgar Frank J
Published: September 2018

Aim

To examine key outcomes in the education of young people with and without neurodisabilities, and to investigate additional disparities in educational achievement in relation to socio‐economic background.

Method

Data were collected on 2488 Canadian children (age range 10–11y) in 1994 and 1995 from the National Longitudinal Survey of Children and Youth whom were followed for 14 years. We performed separate, discrete‐time survival analysis to investigate the effects of having a neurodisability on high school completion, enrolment in post‐secondary education (PSE), and PSE completion.

Results

The baseline prevalence of neurodisabilities was 12%. Fewer children with neurodisabilities completed high school or enrolled in PSE, compared to children without neurodisabilities, irrespective of parental education. The likelihood that students with neurodisabilities completed PSE differed according to their parents' education: students with neurodisabilities living in less‐educated families were about half as likely to complete PSE themselves.

Interpretation

Children with neurodisabilities receive less education than children without neurodisabilities. Children from families with low educational attainment appear to be particularly vulnerable.

What this paper adds

Twelve per cent of children in Canada aged 10 years to 11 years have a neurodisability.

High school completion rate was 70% for children with neurodisabilities versus 94% for children without neurodisabilities.

Children with neurodisabilities from less‐educated families are particularly vulnerable to lower educational achievement.
Seizure evolution can be characterized as path through synaptic gain space of a neural mass model
Authors: Fan Xiaoya , Gaspard Nicolas , Legros Benjamin , Lucchetti Federico , Ercek Rudy , Nonclercq Antoine
Published: September 2018

Physiologically based models could facilitate better understanding of mechanisms underlying epileptic seizures. In this paper, we attempt to reveal the dynamic evolution of intracranial EEG activity during epileptic seizures based on synaptic gain identification procedure of a neural mass model. The distribution of average excitatory, slow and fast inhibitory synaptic gain in the parameter space and their temporal evolution, i.e., the path through the model parameter space, were analyzed in thirty seizures from ten temporal lobe epileptic patients. Results showed that the synaptic gain values located roughly on a plane before seizure onset, dispersed during seizure and returned to the plane when seizure terminated. Cluster analysis was performed on seizure paths and demonstrated consistency in synaptic gain evolution across different seizures from the individual patient. Furthermore, two patient groups were identified, each one corresponding to a specific synaptic gain evolution in the parameter space during a seizure. Results were validated by a bootstrapping approach based on comparison with random paths. The differences in the path revealed variations in EEG dynamics for patients despite showing identical seizure onset pattern. Our approach may have the potential to classify the epileptic patients into subgroups based on different mechanisms revealed by subtle changes in synaptic gains and further enable more robust decisions regarding treatment strategy.
Predicting coral community recovery using multi‐species population dynamics models
Authors: Kayal Mohsen , Lenihan Hunter S. , Brooks Andrew J. , Holbrook Sally J. , Schmitt Russell J. , Kendall Bruce E.
Published: September 2018

Predicting whether, how, and to what degree communities recover from disturbance remain major challenges in ecology. To predict recovery of coral communities we applied field survey data of early recovery dynamics to a multi‐species integral projection model that captured key demographic processes driving coral population trajectories, notably density‐dependent larval recruitment. After testing model predictions against field observations, we updated the model to generate projections of future coral communities. Our results indicated that communities distributed across an island landscape followed different recovery trajectories but would reassemble to pre‐disturbed levels of coral abundance, composition, and size, thus demonstrating persistence in the provision of reef habitat and other ecosystem services. Our study indicates that coral community dynamics are predictable when accounting for the interplay between species life‐history, environmental conditions, and density‐dependence. We provide a quantitative framework for evaluating the ecological processes underlying community trajectory and characteristics important to ecosystem functioning.
Genetic decline, restoration and rescue of an isolated ungulate population
Authors: Poirier Marc‐Antoine , Coltman David W. , Pelletier Fanie , Jorgenson Jon , Festa‐Bianchet Marco
Published: September 2018

Isolation of small populations is expected to reduce fitness through inbreeding and loss of genetic variation, impeding population growth and compromising population persistence. Species with long generation time are the least likely to be rescued by evolution alone. Management interventions that maintain or restore genetic variation to assure population viability are consequently of significant importance. We investigated, over 27 years, the genetic and demographic consequences of a demographic bottleneck followed by artificial supplementation in an isolated population of bighorn sheep (Ovis canadensis). Based on a long‐term pedigree and individual monitoring, we documented the genetic decline, restoration and rescue of the population. Microsatellite analyses revealed that the demographic bottleneck reduced expected heterozygosity and allelic diversity by 6.2% and 11.3%, respectively, over two generations. Following supplementation, first‐generation admixed lambs were 6.4% heavier at weaning and had 28.3% higher survival to 1 year compared to lambs of endemic ancestry. Expected heterozygosity and allelic diversity increased by 4.6% and 14.3% after two generations through new alleles contributed by translocated individuals. We found no evidence for outbreeding depression and did not see immediate evidence of swamping of local genes. Rapid intervention following the demographic bottleneck allowed the genetic restoration and rescue of this bighorn sheep population, likely preventing further losses at both the genetic and demographic levels. Our results provide further empirical evidence that translocation can be used to reduce inbreeding depression in nature and has the potential to mitigate the effect of human‐driven environmental changes on wild populations.
The genetic legacy of 50 years of desert bighorn sheep translocations
Authors: Jahner Joshua P. , Matocq Marjorie D. , Malaney Jason L. , Cox Mike , Wolff Peregrine , Gritts Mitchell A. , Parchman Thomas L.
Published: September 2018

Conservation biologists have increasingly used translocations to mitigate population declines and restore locally extirpated populations. Genetic data can guide the selection of source populations for translocations and help evaluate restoration success. Bighorn sheep (Ovis canadensis) are a managed big game species that suffered widespread population extirpations across western North America throughout the early 1900s. Subsequent translocation programs have successfully re‐established many formally extirpated bighorn herds, but most of these programs pre‐date genetically informed management practices. The state of Nevada presents a particularly well‐documented case of decline followed by restoration of extirpated herds. Desert bighorn sheep (O. c. nelsoni) populations declined to less than 3,000 individuals restricted to remnant herds in the Mojave Desert and a few locations in the Great Basin Desert. Beginning in 1968, the Nevada Department of Wildlife translocated ~2,000 individuals from remnant populations to restore previously extirpated areas, possibly establishing herds with mixed ancestries. Here, we examined genetic diversity and structure among remnant herds and the genetic consequences of translocation from these herds using a genotyping‐by‐sequencing approach to genotype 17,095 loci in 303 desert bighorn sheep. We found a signal of population genetic structure among remnant Mojave Desert populations, even across geographically proximate mountain ranges. Further, we found evidence of a genetically distinct, potential relict herd from a previously hypothesized Great Basin lineage of desert bighorn sheep. The genetic structure of source herds was clearly reflected in translocated populations. In most cases, herds retained genetic evidence of multiple translocation events and subsequent admixture when founded from multiple remnant source herds. Our results add to a growing literature on how population genomic data can be used to guide and monitor restoration programs.
Recruitment variation disrupts the stability of alternative life histories in an exploited salmon population
Authors: DeFilippo Lukas B. , Schindler Daniel E. , Ohlberger Jan , Schaberg Kevin L. , Foster Matt Birch , Ruhl Darin , Punt André E.
Published: September 2018

Males of many fish species exhibit alternative reproductive tactics, which can influence the maturation schedules, fishery productivity, and resilience to harvest of exploited populations. While alternative mating phenotypes can persist in stable equilibria through frequency‐dependent selection, shifts in tactic frequencies have been observed and can have substantial consequences for fisheries. Here, we examine the dynamics of precocious sneaker males called “jacks” in a population of sockeye salmon (Oncorhynchus nerka) from Frazer Lake, Alaska. Jacks, which are of little commercial value due to their small body sizes, have recently been observed at unusually high levels in this stock, degrading the value of regional fisheries. To inform future strategies for managing the prevalence of jacks, we used long‐term monitoring data to identify what regulates the frequencies of alternative male phenotypes in the population over time. Expression of the jack life history could not be explained by environmental factors expected to influence juvenile body condition and maturation probability. Instead, we found a strong positive association between the proportion of individuals maturing as jacks within a cohort and the prevalence of jacks among the males that sired that cohort. Moreover, due to differences in age‐at‐maturity between male phenotypes, and large interannual variability in recruitment strength, jacks from strong year‐classes often spawn among older males from the weaker recruitments of earlier cohorts. Through such “cohort mismatches,” which are amplified by size‐selective harvest on older males, jacks frequently achieve substantial representation in the breeding population, and likely high total fertilizations. The repeated occurrence of these cohort mismatches appears to disrupt the stabilizing influence of frequency‐dependent selection, allowing the prevalence of jacks to exceed what might be expected under equilibrium conditions. These results emphasize that the dynamics of alternative life histories can profoundly influence fishery performance and should be explicitly considered in the management of exploited populations.
Biological variation of routine haematology and biochemistry measurands in the horse
Authors: Wright M. E. , Croser E. L. , Raidal S. , Baral R. M. , Robinson W. , Lievaart J. , Freeman K. P.
Published: September 2018

Background

Clinical pathology results are typically interpreted by referring to population‐based reference intervals. The use of individualised (subject‐based) reference intervals is more appropriate for measurands with a high degree of variation between individuals.

Objectives

To determine the biological variation of routinely analysed equine haematology and biochemistry measurands and calculate indices of individuality and reference change values which enable production of individualised reference intervals, in a group of healthy, privately owned horses.

Study design

In a prospective cohort study, thirty‐nine privately owned horses were sampled by jugular venipuncture for analysis of haematology and biochemistry measurands at weekly intervals for 6 weeks.

Methods

Haematology was analysed on the day of collection. Serum was frozen and biochemistry analyses performed on thawed samples. Duplicate results were obtained and the coefficient of variation was calculated for analytical variation, within‐subject variation and between‐subject variation. The index of individuality and reference change value were derived for each measurand.

Results

Haematology (red blood cell count, mean corpuscular haemoglobin and mean cell volume) and biochemistry measurands (total protein, globulins, albumin, gamma‐glutamyl transferase, aspartate aminotransferase) demonstrated high individuality, indicating that individualised reference intervals are more appropriate for evaluation of these measurands. Two haematology (mean corpuscular haemoglobin concentration and platelets) and three biochemistry measurands (chloride, glucose and sodium) had low individuality, indicating that the use of traditional population‐based reference intervals is appropriate for these measurands. Remaining measurands had intermediate individuality suggesting interpretation of the reference change value should occur with consideration of the population‐based reference interval.

Main limitations

The use of privately owned horses, variable management and environmental factors.

Conclusions

The use of individualised reference intervals is justified for many measurands in horses, supporting the use of serial sampling, consideration of biological variation and application of reference change values for improved clinical decision making and patient management in equine practice.
Desert leaf litter decay: Coupling of microbial respiration, water‐soluble fractions and photodegradation
Authors: Day Thomas A. , Bliss Michael S. , Tomes Alexander R. , Ruhland Christopher T. , Guénon René
Published: September 2018

The mechanisms of plant litter decay in drylands are poorly understood, limiting the accuracy of nutrient‐cycling models for these systems. We monitored the decay of 12 leaf litter types on the soil surface of the Sonoran Desert for 34 months and assessed what traits predicted mass loss and how exposure to different wavebands of sunlight influenced mass loss. Mass loss varied considerably among litter types, ranging from 42%–96% after 34 months in full sunlight. Traditional indices of litter quality (e.g., initial C:N or lignin:N ratios) failed to predict differences in mass loss among litter types. The strongest predictor of mass loss was the microbial respiration rate of initial litter, which explained 45%–54% of the variation in loss among litter types. Microbial respiration rates were not correlated with traditional indices of litter quality, but were positively correlated with the water‐soluble fraction in litter and concentrations of dissolved organic C in this fraction. Traditional indices of litter quality failed to predict decay likely because they did a poor job of predicting microbial degradability of litter, not because microbial degradation was a minor driver of decay. In all radiation‐exposure treatments, water‐soluble fractions and respiration rates increased through decay and were several times higher after 34 months than initially. Hence, labile pools and microbial degradability of litter increased through decay in contrast to traditional views that labile pools decline and constrain microbes. Litter exposed to UV or UV through blue radiation wavelengths, lost on average 1.3 times or 1.5 times more mass, respectively, than litter not exposed to these wavebands. The magnitude of this photodegradation was greater in litter types that had higher initial concentrations of hemicellulose and cellulose per unit surface area. Litter exposed to full sun had higher water‐soluble fractions and usually had higher respiration rates, illustrating that sunlight accelerated microbial degradation by increasing labile pools. The processes driving litter decay appeared to differ appreciably from mesic systems and involved strong couplings between abiotic and biotic drivers.
Soil N2O emissions as affected by long‐term residue removal and no‐till practices in continuous corn
Authors: Yuan Mingwei , Greer Kristin D. , Nafziger Emerson D. , Villamil Maria B. , Pittelkow Cameron M.
Published: September 2018

The environmental consequences of residue removal practices to support cellulosic biofuel production remain poorly understood. In the U.S. Midwest, corn (Zea mays L.) stover removal combined with no‐till practices may increase or decrease soil N2O emissions by influencing soil moisture, temperature, and nutrient dynamics, yet empirical evidence from long‐term field experiments is inconsistent. We investigated the effects of residue management (residue retained or removed) and tillage (chisel‐till or no‐till) on cumulative soil nitrous oxide (N2O) emissions, grain yield, and yield‐scaled N2O emissions in a 3‐year study initiated 10 years after treatment implementation in a long‐term, continuous corn experiment in Illinois, United States. Crop yields were affected by treatment in only one of three study years, with the combination of residue removal and no‐till reducing yields compared to both chisel‐till treatments. Cumulative N2O emissions, soil inorganic N concentrations, and yield‐scaled N2O emissions differed over the 3‐year period and were significantly affected by tillage, with no response to residue management. In 2 years, no‐till decreased cumulative N2O emissions and yield‐scaled N2O emissions by an average of 64% and 60%, respectively. Correlations between daily N2O fluxes and soil moisture, temperature, and inorganic N concentrations suggested that the relative importance of these variables changed depending on year and treatment. While more research across a range of sites and management practices is needed, our findings support previous studies which have challenged IPCC methodology assumptions regarding the effects of residue removal on N2O emissions. We conclude there is inherent difficulty in predicting the impacts of residue removal due to the complexity of soil processes underlying N2O emissions coupled with inter‐annual weather variability in this rainfed continuous corn system. Future efforts to evaluate the net greenhouse gas emissions of cellulosic biofuel production may benefit from accounting for this uncertainty.
Preparation and corrosion behavior studies of chemically bonded phosphate ceramic coating reinforced with modified multi‐walled carbon nanotubes (MWCNTs)
Authors: Rongli Xu , Bian Da , Aradhyula Thirumala Vasu , Chavali Murthy , Zhao Yongwu
Published: September 2018

To improve the corrosion resistance of the chemically bonded phosphate ceramic coating, the MWCNTs are selected as the reinforcement after the modification. Through the analysis of TEM, Raman, XRD, and FTIR, it can be shown that MWCNTs are modified with carboxyl groups and the surfactant after treatment, and show good dispersion. In addition, the electrochemical experiments were carried out with 3.5 wt% NaCl solution to investigate the corrosion behavior of the coatings. The results suggest that the corrosion resistance of coatings is improved with the introduction of MWCNTs and the corrosion resistance increases with the increase in MWCNTs. Besides, the corrosion mechanism of MWCNTs reinforced coating corrosion resistance was also investigated based on the corrosion behavior and microstructural characterizations. The gel strength is improved with the addition of MWCNTs because of its strong strength, which can prevent crack occurring and form the bridge when crack happens. Therefore, H2O, O2, and Cl− can be prevented from reaching to the substrate, which leads to good corrosion resistance.
Autopsy of refractory lining in anode kilns with open and closed design
Authors: Brandvik Trond , Wang Zhaohui , Ratvik Arne Petter , Grande Tor
Published: September 2018

Aluminosilicate refractory lining constitutes a major part of anode baking kilns, and during anode baking the lining is exposed to harsh conditions which limits the lifetime. Here, autopsies of refractory linings from both an open and closed top furnace are reported aiming to determine the microstructural and mineralogical changes in the lining during operation. Significant variations in density and porosity were observed, both across the brick cross sections, but also for the vertical position in the lining. The chemical and mineralogical composition of the bricks were investigated by electron microscopy and X‐ray diffraction. Only minor changes in the mineralogical composition of the materials were observed, and sodium originating from green anodes was only observed to a minor degree. Evidence of silicon oxide transport from the lower to the upper part of the linings was observed, reflecting the changes in reducing‐oxidizing conditions during an anode baking cycle. The main degradation mechanisms in these linings were due to densification of the material over time, particularly the uneven densification across a lining wall. The present findings are discussed and related to the main differences in the two furnace designs.
Dilute Russell viper venom time interpretation and clinical correlation: A two‐year retrospective institutional review
Authors: Jacquot Cyril , Wool Geoffrey D. , Kogan Scott C.
Published: September 2018

Introduction

The dilute Russell viper venom time (dRVVT) detects lupus anticoagulant (LA). International Society for Thrombosis and Haemostasis (ISTH) guidelines specify positivity criteria, which differ from the assay manufacturer's criteria.

Methods

Two years of dRVVT testing at our institution were reviewed. For patients with prolonged dRVVT screening times, we evaluated dRVVT results by ISTH and manufacturer's criteria and correlated with the results of other antiphospholipid syndrome (APS) testing (LA‐sensitive activated partial thromboplastin time and antiphospholipid antibodies) and with history of thromboembolism and other APS manifestations.

Results

Approximately one‐fifth of dRVVTs exhibited a prolonged screening time. Among first prolonged dRVVTs, 35% were positive by both ISTH and manufacturer criteria, 44% met neither criteria, and 20% were equivocal (positive by only ISTH or manufacturer). Positivity by ISTH guidelines alone correlated better with other positive APS tests than manufacturer criteria positivity. Positive dRVVTs by both criteria correlated even more strongly with other positive APS assays. We investigated the likelihood of eventual APS diagnosis depending on the testing indication. No patient tested for LA solely for prolonged screening aPTT was subsequently diagnosed with APS. In patients with thrombosis, prolonged dRVVT clotting time not meeting both ISTH and manufacturer criteria was rarely associated with eventual APS diagnosis.

Conclusion

We examined the correlation of dRVVT results with other APS testing and clinical outcomes. Interpretation method impacted how dRVVT results related to other APS testing, and, in limited data, to clinical findings. Patients with prolonged dRVVTs meeting only one set of positivity criteria rarely received an APS diagnosis.
Preparation of Er3+/Yb3+ co‐doped citrate microstructure fiber of large mode field and its 3.0 μm laser performance
Authors: Zhou Dechun , Jin Danyang , Lan ZhiDan , Bai XueMei
Published: September 2018

The double‐cladding Er3+/Yb3+ co‐doped bismuth germanium gallate microstructure fiber of large mode, with the core diameter of 30.6 μm, the inner cladding air pore diameter of about 3.06 μm and a lattice constant of 10.2 μm is prepared by a bundle‐drawing method. The spectral characteristics at 975 nm wavelength were studied and the results show that the maximum fluorescence intensity and the high gain quality factor of the fiber core glass can be obtained when the molar ratio of Er3+ to Yb3+ is 0.5%:2% and its emission cross section is up to 10.9 × 10−21 cm2. A stable laser output with a maximum power of 51.16 mW and a wavelength of 2710 nm was obtained in a microstructure optical fiber with a length of 160 mm employing a independently constructed fiber laser with a cascade structure, whose pump light power was 561 mW, the slope efficiency was 6.89%, the effective mode field area is about 576 μm2 and the beam quality factor M2 < 1.02. The double‐cladding Er3+/Yb3+ co‐doped bismuth germanium gallate microstructure fiber of large mode has excellent laser properties and is an ideal optical fiber material for the development of the 3.0 μm laser.
Competitive growth of Al2O3/YAG/ZrO2 eutectic ceramics during directional solidification: Effect of interfacial energy
Authors: Wang Xu , Zhong Yujie , Sun Qian , Qi Dongqing , Yan Fuxue , Xian Quangang , Wang Dong , Du Kui , Wang Jingyang
Published: September 2018

The microstructure evolution and growth behavior of the Al2O3/Y3Al5O12(YAG)/ZrO2 ternary eutectic ceramics during directional solidification were well investigated. During directional solidification of the Al2O3/YAG/ZrO2 ternary eutectic ceramics, {} Al2O3 paralleled with {001}ZrO2 while they did not parallel with {001}YAG at the same time in the competitive growth stage. All of the interfaces parallel to each other finally. The area percentage of the Al2O3/ZrO2 and YAG/ZrO2 interfaces are 40.4 ± 0.2% and 30.8 ± 0.1%, respectively, higher than that of the Al2O3/YAG (28.8 ± 0.2%). The content of Al2O3 and YAG phases are 39.9% and 41.1%, respectively, almost double of that of ZrO2. The interfaces of Al2O3/ZrO2 and YAG/ZrO2 are shorter and more dispersed than that of the Al2O3/YAG. It was found that the interfacial energy of Al2O3/ZrO2 and YAG/ZrO2 interfaces are lower than that of Al2O3/YAG. It can be concluded that interfacial energy plays a decisive role in affecting the crystallographic orientation and interfaces distribution in the Al2O3/YAG/ZrO2 eutectic since the interfaces of Al2O3/ZrO2 and YAG/ZrO2 with lower interfacial energy can be formed more easily during directional solidification. Therefore, the contents of Al2O3/ZrO2 and YAG/ZrO2 interfaces are higher. This study can provide theoretical guidance for interface design of multi‐phase materials.
Strain rate dependence of the contribution of surface diffusion to bulk sintering viscosity
Authors: Delannay Francis , Brassart Laurence
Published: September 2018

Modeling of bulk sintering viscosity usually neglects the contribution of pore surface diffusion with respect to grain‐boundary diffusion. This approximation is questionable at the high densification rates used today in advanced fast sintering techniques. A two‐dimensional analysis of the problem shows that the influence of surface diffusion on bulk viscosity at high strain rate can be decomposed as the sum of two terms: a term linked to the change in pore surface curvature and a term linked to the change in grain‐boundary size. The computational procedure relies on the partition of pore profile evolution into a transient component accounting for non‐densifying phenomena and an asymptotic component accounting for strain‐rate‐controlled phenomena. The largest impact of surface diffusion is found to arise from the change in grain‐boundary size. It follows a transition from Newtonian viscosity at low strain rate to non‐Newtonian viscosity which, during densification, increases nearly linearly with strain rate. In some conditions, viscosity can then reach more than twice the value estimated when neglecting pore surface diffusion. Reversely, expansion is accompanied by a decrease in grain‐boundary size which causes a decrease in viscosity and can lead to grain separation at high strain rate.
Potential need for expanded pharmacologic treatment and lifestyle modification services under the 2017 ACC/AHA Hypertension Guideline
Authors: Ritchey Matthew D. , Gillespie Cathleen , Wozniak Gregory , Shay Christina M. , Thompson‐Paul Angela M. , Loustalot Fleetwood , Hong Yuling
Published: September 2018

Application of the 2017 ACC/AHA Hypertension Guideline expands the number of US adults requiring blood pressure (BP) management. The authors use 2011‐2014 NHANES data to describe the population groups most affected by the new guideline, compared with the previous JNC‐7 guideline, and describe the previous interaction with the health care sector among those adults recommended new or intensified pharmacologic treatment and/or lifestyle modification. The 2017 Hypertension Guideline reclassifies 32.3 million US adults as newly hypertensive and recommends BP‐related treatment of 133.7 million adults, including 57.8 million with uncontrolled BP recommended to initiate or intensify pharmacologic treatment and 50.5 million newly recommended lifestyle modification alone. An estimated 13.1 million (22.7%) adults recommended to initiate or intensify pharmacologic treatment, and 20.6 million (40.8%) adults newly recommended lifestyle modification alone report not having established health care linkages. Among the adults newly recommended lifestyle modification alone, the odds of reclassification from no recommended intervention, under JNC‐7, to recommended lifestyle modification alone were lower for adults with established linkages to care (aOR: 0.78 [95% CI: 0.67‐0.91]) compared to those without, decreased with increasing age, were greater for men (1.72 [1.52‐1.94]) compared to women and were greater for obese adults (1.23 [1.00‐1.53]) compared with normal or underweight adults. Application of the 2017 Hypertension Guideline increases the number and alters the distribution of US adults in need of initiating or intensifying BP treatment. This includes identifying millions of US adults who previously had limited interaction with health care and are now recommended new or intensified pharmacologic treatment and/or lifestyle modification.
Relationship between thyroid function and elevated blood pressure in euthyroid adults
Authors: Gu Yeqing , Zheng Lixiao , Zhang Qing , Liu Li , Meng Ge , Yao Zhanxin , Wu Hongmei , Xia Yang , Bao Xue , Shi Hongbin , Wang Honglei , Xu Haiyan , Sun Shaomei , Wang Xing , Zhou Ming , Jia Qiyu , Song Kun , Niu Kaijun
Published: September 2018

Thyroid hormones (THs) have profound effects on cardiovascular functions, suggesting that THs may contribute to the development of elevated blood pressure (BP). Few studies, however, have systematically assessed the relationship between THs and elevated BP. We therefore conducted a cross‐sectional study to examine how serum THs concentrations are related to the prevalence of elevated BP in a euthyroid population. This study (n = 12 487) was performed in Tianjin, China. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid‐stimulating hormone (TSH) levels were measured by chemiluminescence immunoassay. Elevated BP was defined according to the JNC 8 criteria. Analysis of covariance and multiple logistic regression models were used to assess the relationships between FT3, FT4, and TSH quartiles and elevated BP. The multivariable‐adjusted odds ratios (95% confidence interval) of elevated BP for gradual increase in the FT3, FT4, and TSH quartiles, when compared to the lowest quartiles were 1.08 (0.97, 1.21), 1.24 (1.12, 1.39), and 1.32 (1.18, 1.47); 1.18 (1.06, 1.32), 1.18 (1.06, 1.31), and 1.24 (1.11, 1.38); 1.06 (0.96, 1.19), 1.06 (0.95, 1.18), and 1.03 (0.93, 1.15), respectively. Our study demonstrated that FT3 and FT4 are positively related to the prevalence of elevated BP in euthyroid adults, but no significant relationship was found between TSH and elevated BP.
Repair of aged bulk‐fill composite with posterior composite: Effect of different surface treatments
Authors: Ayar Muhammet Kerim , Guven Mehmet Esad , Burduroglu Hatice Defne , Erdemir Fatih
Published: September 2018

Objective

In the present study, the ability of posterior resin composite to repair aged bulk‐fill resin composite and vice versa were assessed by shear bond strength testing.

Materials and Methods

Resin composite substrates were aged and surfaces were abraded with abrasive papers, then bulk‐fill substrates were repaired with posterior resin composite and vice versa using different surface treatments (no surface treatment [control]; etching with 37% phosphoric acid [H3PO4] for 20 seconds; etching with 10% hydrofluoric acid [HF] for 20 seconds; etching with 37% H3PO4 for 20 seconds + adhesive application; etching with 10% HF for 20 seconds + adhesive application; adhesive application only). Shear bond strengths (SBS) were then measured and surface roughness values (Ra) were determined. Cohesive strengths of nonaged resin composites were measured and used as reference groups. Resin composite surfaces after acid etching were evaluated by SEM. Data were analyzed using ANOVA and Fisher's LSD tests (P < .05).

Results

ANOVA showed that resin composite repair type did not affect SBS significantly (P = .850), while it showed that surface treatments significantly affected the SBS (P = .000). Only a combination of etching with 10% HF for 20 seconds with resin adhesive application provided similar SBS values with those of the positive control.

Conclusions

It was concluded that the aged bulk‐fill resin composite would be effectively repaired with conventional posterior resin composite or vice versa if proper repair protocol was deployed.

Clinical Significance

The combination of 10% HF etching and adhesive application would provide efficient repair strength when the aged bulk fill resin composite is repaired with conventional posterior resin composite or vice versa.
Color stability of a bis‐acryl composite resin subjected to polishing, thermocycling, intercalated baths, and immersion in different beverages
Authors: Macedo Maria Gracinda F. P. , Volpato Claudia A. M. , Henriques Bruno A. P. C. , Vaz Paula C. S. , Silva Filipe S. , Silva César F. C. L.
Published: September 2018

Objective

To evaluate the color of a bis‐acryl resin after polishing, aging, and colorants.

Materials and Methods

From the 140 disks obtained, 35 were not polished (NP), 35 were polished with 3‐μm (3P), 35 with 3‐ and 1‐μm (1P), and 35 with 3‐, 1‐, and 0.5‐μm sized particles (05P). Five disks of each group were thermocycled for 20, 100, and 200 cycles. Sixty disks were thermocycled and kept in beverages (tea, wine, and coffee) after four cycles. Sixty disks were immersed in the beverages for 24 hours, a week, and a month. The coordinates L*a*b* were measured and the color differences were analyzed by ANOVA. The lightness, chroma, and hue differences were evaluated by repeated measures ANOVA. Comparisons were made with Tukey's test (α = 0.05).

Results

Similar behaviors were observed between 3P and 05P groups (1.53 and 1.95ΔE00) (P < .05). The NP group submitted to 200 cycles showed the biggest color differences (3.02) (P = .003). The greatest color differences were observed in the NP group submitted to immersion in coffee (8.30) and wine (7.93) (P < .05).

Conclusions

The polished surfaces were the least stained. Coffee and wine provided the greatest color changes, both for baths and immersions.

Clinical Significance

Polishing of provisional surfaces restorations made of bis‐acrylic resin is essential to minimize staining caused by aging and use of colorants, regardless of the particle size present in the polishing paste. The contact with coffee and red wine should be avoided, especially for clinical times greater than 1 week.
Interventions for dental fluorosis: A systematic review
Authors: Di Giovanni Tamara , Eliades Theodore , Papageorgiou Spyridon N.
Published: September 2018

Objective

Dental fluorosis has considerable implications on the patients' quality of life. The present study assesses the comparative effectiveness of the various interventions for the treatment of fluorosed enamel.

Materials and Methods

Nine databases were searched from inception to December 2016 for randomized trials. After duplicate study selection, data extraction, and risk of bias assessment, mean differences (MD) or Relative Risks and the corresponding 95% confidence intervals (CIs) were calculated and assessed with the GRADE approach.

Results

Six trials with a total of 348 patients (at least 40% male/60% female) with a mean age of 17.7 years treated with bleaching, microabrasion, or resin infiltration were included. Evidence of low quality indicated that microabrasion resulted in smaller esthetic improvement compared to bleaching (MD = −2.9; 95% CI = −3.4 to −2.5). Evidence of moderate quality indicated that compared to bleaching a greater esthetic improvement was seen with resin infiltration (MD = 3.6; 95% CI = 2.7‐4.6) or a combination of bleaching with resin infiltration (MD = 3.5; 2.8‐3.7). However, all comparisons were supported from single trials and therefore caution is warranted.

Conclusions

Based on the existing limited evidence, resin infiltration seems to be the most promising treatment for dental fluorosis, followed by bleaching and microabrasion.

Clinical Significance

For this systematic review, which was registered beforehand in PROSPERO (CRD42016053492), we synthesized evidence from existing randomized clinical trals on humans to see which treatment is most effective for the esthetic rehabilitation of dental fluorosis, the prevalence of which is seeing a worldwide steady increase. We found that resin infiltration seems to be the most effective treatment approach for lesions of mild to moderate severity, followed by bleaching, and finally microabrasion.

Our study's strengths are its a priori registration, wide search, quality check according to Cochrane guidelines, and the use of a new robust analytic method to provide valid clinical recommendations according to the principles of evidence‐based medicine.
Auxiliary UV light devices for removal of fluorescent resin residues after bracket debonding
Authors: Salomão Fabio Martins , Rocha Rafael Santos , Franco Laura Molinar , Sundfeld Renato Herman , Bresciani Eduardo , Fagundes Ticiane Cestari
Published: September 2018

Objective

The purpose of this clinical report was to describe the detection of fluorescent resin residue after orthodontic bracket debonding with two UV light devices and analyze the surface morphology of enamel after 1 year.

Clinical considerations

A 22‐year‐old woman had orthodontic brackets removed by a previous dentist; however, resin residue was left on the enamel of the maxillary teeth. After confirming the fluorescent property of the resin, different protocols were used for each half of the maxillary arch. The first method, a black light lens was attached to a light‐curing device to detect resin fluorescence, followed by polishing with silicone rubber tips. The second method used a light emitting diode light system attached to and activated by a high‐speed handpiece, followed by polishing with discs. Both methods were completed with diamond polishing paste applied with felt discs. Polyvinyl siloxane impressions were made initially, after residue removal, after finishing and after polishing for morphologic analysis. The results were evaluated with photographs and the scanning electron microscope images made of resin casts from the impressions. A follow‐up was made after 1 year.

Conclusions

Both methods yielded a satisfactory clinical outcome, with a smooth surface, acceptable surface gloss and minimal tooth wear. The use of a UV device that excites fluorescence is recommended for the controlled removal of resin residue on enamel.

Clinical Significance

The controlled removal of resin residue from enamel after orthodontic treatment is challenging but can be improved with auxiliary methods for detecting resin residues. This clinical report describes two types of devices that excite fluorescent resins in a more rapid and precise technique to guide the practitioner in the controlled removal of residual resin on teeth.