bluuebunny/crossref_metadata_2025 huggingface dataset:
Avian migration and the distribution of malaria parasites in New World passerine birds
Authors: Ricklefs Robert E. , Medeiros Matthew , Ellis Vincenzo A. , Svensson‐Coelho Maria , Blake John G. , Loiselle Bette A. , Soares Leticia , Fecchio Alan , Outlaw Diana , Marra Peter P. , Latta Steven C. , Valkiūnas Gediminas , Hellgren Olof , Bensch Staffan
Published: December 2016

Aim

Migrating birds transport their parasites, often over long distances, but little is known about the transfer of these parasites to resident hosts in either the wintering or breeding ranges of the migratory host populations. We investigated the haemosporidian parasite faunas of migratory and resident birds to determine connections among distant parasite faunas, plausibly brought about by migratory host populations.

Location

Samples were obtained, primarily during or shortly after the local breeding season, throughout the Americas, from the United States through the Caribbean Basin and into northern South America.

Methods

Infections were identified by PCR and sequencing of parasite DNA in avian blood samples. The analyses were based on c. 4700 infections representing 79 parasite lineages of Plasmodium and Haemoproteus spp. Geographical connections of lineages between regions in the Americas were compared to those in the Euro‐African migration system, where migration distances are longer for many host species and the migrant and resident avifaunas in the wintering areas are phylogenetically more divergent.

Results

Haemosporidian lineages exhibited considerable variation in distribution in the Americas, and patterns of distribution differ markedly between the Americas and the Euro‐African migration system. In particular, few lineages were recovered from resident species in both temperate and tropical latitudes, particularly in the Euro‐African system, in which a large proportion of lineages were restricted to migrants. Parasite lineages in the Euro‐African system exhibited considerable phylogenetic conservatism in their distributions, that is, a tendency of related lineages to exhibit similar geographical distributions. In contrast, clades of parasites in the Americas displayed more geographical diversity, with four of 12 clades exhibiting all four of the distribution types representing the combinations of resident and migrant host species in both temperate and tropical latitudes.

Main conclusions

Long‐distance migrants connect communities of avian haemosporidian parasites in breeding and wintering areas with disparate avifaunas and different vector communities. The degree of parasite lineage sharing between migrants and residents in breeding and wintering areas appears to reflect, to a large degree, the taxonomic similarity of migrants to the resident species in both areas.
Evaluation of the caries‐preventive effect of toothpaste containing surface prereacted glass‐ionomer filler
Authors: Amaechi Bennett Tochukwu , Key Meredith C. , Balu Sabarathnam , Okoye Linda Ogechukwu , Gakunga Peter Thiuri
Published: December 2016

Aim

Although fluoride interventions have the most consistent benefit in preventing caries, caries still develop in high‐risk individuals. Authors have evaluated the effectiveness of toothpastes containing surface prereacted glass‐ionomer (S‐PRG) filler in preventing tooth demineralization.

Methods

Human tooth enamel blocks were randomly assigned to six groups (30 blocks/group): no treatment (a), and toothpaste containing either 1500 ppm fluoride as sodium monofluorophosphate (NaMFP) (b), 0 wt% S‐PRG (b), 1 wt% S‐PRG (d), 5 wt% S‐PRG (e), or 20 wt% S‐PRG (f). Early caries developed on each block by 7‐days demineralization using a microbial caries model. Mineral loss (Δz) and lesion depth (LD) were determined using transverse microradiography.

Results

Relative to the control, all toothpastes, except 0% S‐PRG, significantly (analysis of variance, Tukey's, P<.0001) reduced Δz and LD at varying percentages. With regard to Δz, all comparisons were significant (P<.0001), except 0% S‐PRG vs the control. Otherwise, S‐PRG 1%, 5%, and 20% had 0.50, 0.37, and 0.27 times Δz compared to the control, respectively, while NaMFP had 0.61 times Δz compared to the control. LD followed an almost similar trend as Δz.

Conclusions

The findings of the present study demonstrate the effectiveness of toothpaste containing S‐PRG filler in inhibiting tooth demineralization in the presence of bacterial plaque, thus highlighting its potential as an effective caries‐control tool for individuals at high risk of developing caries.
Integrated Thinking and the Transparency of Tax Disclosures in the Corporate Reports of Firms
Authors: Venter Elmar R. , Stiglingh Madeleine , Smit Anna‐Retha
Published: December 2016

The purpose of our study was to link two global corporate developments, namely integrated thinking and the transparency of tax disclosures. The International Integrated Reporting Council's long‐term vision is for integrated thinking to be embedded in mainstream business practice, facilitated by integrated reporting. The development of the transparency of tax disclosures was driven by tax avoidance practices of multinational companies. The vision of embedding integrated thinking into mainstream business and the increased focus on the transparency of tax disclosures have developed independently, but thus far there has been no serious consideration of how they may be related. We argue that there is a natural relationship between these two developments. We use PwC's (2014) framework for measuring the transparency of tax disclosures and apply the framework to the corporate reports of a sample of 45 large firms. We use regression analysis to test the association between the transparency of tax disclosures in corporate reports and integrated thinking and find them to be positively associated.
A multilevel framework to reconstruct anatomical 3D models of the hepatic vasculature in rat livers
Authors: Peeters Geert , Debbaut Charlotte , Laleman Wim , Monbaliu Diethard , Vander Elst Ingrid , Detrez Jan R. , Vandecasteele Tim , De Schryver Thomas , Van Hoorebeke Luc , Favere Kasper , Verbeke Jonas , Segers Patrick , Cornillie Pieter , De Vos Winnok H.
Published: December 2016

The intricate (micro)vascular architecture of the liver has not yet been fully unravelled. Although current models are often idealized simplifications of the complex anatomical reality, correct morphological information is instrumental for scientific and clinical purposes. Previously, both vascular corrosion casting (VCC) and immunohistochemistry (IHC) have been separately used to study the hepatic vasculature. Nevertheless, these techniques still face a number of challenges such as dual casting in VCC and limited imaging depths for IHC. We have optimized both techniques and combined their complementary strengths to develop a framework for multilevel reconstruction of the hepatic circulation in the rat. The VCC and micro‐CT scanning protocol was improved by enabling dual casting, optimizing the contrast agent concentration, and adjusting the viscosity of the resin (PU4ii). IHC was improved with an optimized clearing technique (CUBIC) that extended the imaging depth for confocal microscopy more than five‐fold. Using in‐house developed software (DeLiver), the vascular network – in both VCC and IHC datasets – was automatically segmented and/or morphologically analysed. Our methodological framework allows 3D reconstruction and quantification of the hepatic circulation, ranging from the major blood vessels down to the intertwined and interconnected sinusoids. We believe that the presented framework will have value beyond studies of the liver, and will facilitate a better understanding of various parenchymal organs in general, in physiological and pathological circumstances.
Is serum level of nestin useful in detecting epithelial ovarian cancer?
Authors: Sal Veysel , Kahramanoglu Ilker , Bese Tugan , Demirkiran Fuat , Sofiyeva Nigar , Soyman Zeynep , Durmus Sinem , Gelisgen Remisa , Arvas Macit , Uzun Hafize
Published: December 2016

Aim

The aim of the present study was to evaluate the usefulness of nestin as a discriminative marker between benign and malignant ovarian tumors.

Methods

During the 1 year from January 2015 through December 2015, a nonconsecutive series of 80 patients (40 malignant, 40 benign) who underwent surgery for an adnexal mass were enrolled in the study. Intraoperative frozen section evaluation was performed if there was a suspicion in diagnosis. Statistical analyses were performed using spss ver. 16.0, while clinicopathological variables, including the categorical data, were analyzed using the χ2‐test or Fisher's exact test. A P‐value < 0.05 was defined as statistically significant.

Results

Preoperative serum carbohydrate antigen (CA)‐125, CA‐15‐3, and nestin levels were significantly higher in the malignant group compared to patients with benign ovarian tumors (P < 0.001, respectively). Serum nestin levels did not differ significantly on the basis of histologic subtypes. Serum nestin levels had specificity of 89.7%, which demonstrates nestin's sufficiency to distinguish benign from malignant epithelial ovarian tumors. The positive likelihood ratio of nestin was found to be superior to that of CA‐125 and CA‐15‐3.

Conclusion

The results obtained from our study suggest that measurement of nestin level, alongside physical examination, transvaginal ultrasound, and serum CA‐125 and CA‐15‐3 levels, can help differentiate benign ovarian tumors from malignant epithelial ovarian tumors. The findings of our study need to be supported with additional studies.
Cross‐culture and gender invariance of the Warr (1990) job‐related well‐being measure
Authors: Laguna Mariola , Mielniczuk Emilia , Razmus Wiktor , Moriano Juan Antonio , J. Gorgievski Marjan
Published: December 2016

The job‐related affective well‐being measure developed by Warr (1990, J. Occup. Psychol., 63, 193) has been a frequently used tool estimating affect in the work context. The main purpose of this study was to test the measurement invariance of the instrument across cultures and genders. The model with four correlated factors, representing anxiety, comfort, depression, and enthusiasm, had a superior fit compared to alternative models in a sample of 807 employees and was used as the basis of measurement invariance tests. The results of multigroup confirmatory factor analysis showed partial metric invariance across samples of employees from the Netherlands (n = 254), Poland (n = 436), and Spain (n = 207), as well as full scalar invariance across genders (female n = 323; male n = 466). This indicates that cross‐cultural comparisons of relationships between job‐related affect as measured with this instrument and other constructs can be meaningful. Additionally, mean scores on the scales of the instrument can be meaningfully compared across genders, but not across countries.

Practitioner points

Warr's job‐related affective well‐being measure is a valid and reliable operationalization of four correlated affective dimensions: anxiety, comfort, depression, and enthusiasm.

Mean scores on these dimensions can be meaningfully compared across genders, but comparisons of mean scores between countries should be interpreted with caution.
Cognitive Control of Attentional Guidance by Visual and Verbal Working Memory Representations
Authors: Kawashima Tomoya , Matsumoto Eriko
Published: December 2016

Both visual and verbal information in working memory guide visual attention toward a memory‐matching object. We tested whether: (a) visual and verbal representations have different effects on the deployment of attention; and (b) both types of representations can be used equally in a top‐down manner. We asked participants to maintain a visual cue or a verbal cue at the beginning of each trial, and ended with a memory task to ensure that each cue was represented actively in working memory. Before the memory task, a visual search task appeared where validity was manipulated as valid, neutral, or invalid. We also manipulated the probability of valid trials (20%, 50%, and 80%), which had been told to the participants prior to the task. Consistent with earlier findings, attentional guidance by visual representations was modulated by the probability. We also found that this was true for verbal representations, and that these effects did not differ between representation types. These results suggest that both visual and verbal representations in working memory can be used strategically to control attentional guidance.
Towards a multigene phylogeny of the Cymatosiraceae (Bacillariophyta, Mediophyceae) I: novel taxa within the subfamily cymatosiroideae based on molecular and morphological data
Authors: Dąbek Przemysław , Ashworth Matt P. , Witkowski Andrzej , Li Chunlian , Bornman Thomas G. , Gonçalves Vítor , Park Jinsoon , Khim Jong Seong
Published: December 2016

The family Cymatosiraceae, composed of two subfamilies (Cymatosiroideae and Extubocelluloideae), are elongate, non‐pennate diatoms and are commonly reported in marine planktonic and benthic assemblages all over the world. The combination of the gross bilateral symmetry of the frustule and radial symmetry of the valve poration, distinct pore fields at the valve apices and DNA sequence data place this family in the controversial diatom class Mediophyceae, sister to the pennate diatoms. The relationships of the Cymatosiraceae within the Mediophyceae, and the monophyly of the two cymatosiroid subfamilies, have become less stable with the addition of new DNA sequence data. In this paper, we examined 24 cymatosiraceaen strains, including the new taxa Lambertocellus africana (Dąbek & Witkowski) Dąbek, Witkowski & Ashworth comb. nov., Leyanella probus Ashworth, Dąbek & Witkowski sp. nov., and Leyanella pauciporis Ashworth, Dąbek & Park sp. nov. to create the most complete molecular phylogeny of the Cymatosiraceae to date, using a three‐gene (SSU, rbcL and psbC) data set. The results of the phylogenetic analysis supported the monophyly of the Cymatosiraceae, but not the monophyly of the subfamilies Cymatosiroideae and Extubocelluloideae. The phylogenetic analysis also suggested a close relationship of the Cymatosiraceae to the family Eupodiscaceae. The phylogenetic results have lead us to re‐evaluate the taxonomy of L. africana, which is sister to Cymatosira lorenziana rather than Minutocellus as suggested in the original description.
Changes in sleep duration and recreational screen time among Canadians, 1998–2010
Authors: Leech Judith A.
Published: December 2016

It is commonly claimed that sleep duration has declined in recent years – over a period coinciding with a marked increase in personal electronics and communications use. The aim of this study was to assess change in sleep duration among Canadians from 1998 to 2010, and examine any associations with non‐work‐related screen time. The analysis uses population‐representative data from Statistics Canada's General Social Survey cycles of 1998 and 2010; the respective samples numbered 10 749 and 15 390 individuals. Response rates were 80% in 1998 and 55% in 2010. Respondents were aged 15 years and older, residing in private households in the 10 Canadian provinces. The General Social Survey is administered by computer‐assisted telephone interviewing. Data on sleep duration (excluding naps outside essential sleep time) and recreational screen time were obtained using a 24‐h time‐use diary. Survey weights were applied to adjust for non‐response and non‐landline households. Frequencies (respondent characteristics) and averages (time‐use variables) were estimated by age group and sex. Sleep duration was examined by weighted quartile of screen time. Confidence intervals (95%) were calculated around estimates. Average sleep duration increased from 8.1 h in 1998 to 8.3 h in 2010. Average screen time increased from 140 min in 1998 to 154 min in 2010. Sleep duration and screen time were positively related in both years. The percentage of people averaging less than 6 h sleep decreased from 9.6% in 1998 to 8.6% in 2010. Between 1998 and 2010, increases in screen time did not occur at the expense of sleep duration.
Population genomics reveals structure at the individual, host‐tree scale and persistence of genotypic variants of the undomesticated yeast Saccharomyces paradoxus in a natural woodland
Authors: Xia Wenjing , Nielly‐Thibault Lou , Charron Guillaume , Landry Christian R. , Kasimer Dahlia , Anderson James B. , Kohn Linda M.
Published: December 2016

Genetic diversity in experimental, domesticated and wild populations of the related yeasts, Saccharomyces cerevisiae and Saccharomyces paradoxus, has been well described at the global scale. We investigated the population genomics of a local population on a small spatial scale to address two main questions. First, is there genomic variation in a S. paradoxus population at a spatial scale spanning centimetres (microsites) to tens of metres? Second, does the distribution of genomic variants persist over time? Our sample consisted of 42 S. paradoxus strains from 2014 and 43 strains from 2015 collected from the same 72 microsites around four host trees (Quercus rubra and Quercus alba) within 1 km2 in a mixed hardwood forest in southern Ontario. Six additional S. paradoxus strains recovered from adjacent maple and beech trees in 2015 are also included in the sample. Whole‐genome sequencing and genomic SNP analysis revealed five differentiated groups (clades) within the sampled area. The signal of persistence of genotypes in their microsites from 2014 to 2015 was highly significant. Isolates from the same tree tended to be more related than strains from different trees, with limited evidence of dispersal between trees. In growth assays, one genotype had a significantly longer lag phase than the other strains. Our results indicate that different clades coexist at fine spatial scale and that population structure persists over at least a one‐year interval in these wild yeasts, suggesting the efficacy of yearly sampling to follow longer term genetic dynamics in future studies.
The quick and the dead: microbial demography at the yeast thermal limit
Authors: Maxwell Colin S. , Magwene Paul M.
Published: December 2016

The niche of microorganisms is determined by where their populations can expand. Populations can fail to grow because of high death or low birth rates, but these are challenging to measure in microorganisms. We developed a novel technique that enables single‐cell measurement of age‐structured birth and death rates in the budding yeast, Saccharomyces cerevisiae, and used this method to study responses to heat stress in a genetically diverse panel of strains. We find that individual cells show significant heterogeneity in their rates of birth and death during heat stress. Genotype‐by‐environment effects on processes that regulate asymmetric cell division contribute to this heterogeneity. These lead to either premature senescence or early life mortality during heat stress, and we find that a mitochondrial inheritance defect explains the early life mortality phenotype of one of the strains we studied. This study demonstrates how the interplay of physiology, genetic variation and environmental variables influence where microbial populations survive and flourish.
Gasserian Ganglion and Retrobulbar Nerve Block in the Treatment of Ophthalmic Postherpetic Neuralgia: A Case Report
Authors: Huang Jie , Ni Zhongge , Finch Philip
Published: December 2016

Objectives

Varicella zoster virus reactivation can cause permanent histological changes in the central and peripheral nervous system. Neural inflammatory changes or damage to the dorsal root ganglia sensory nerve fibers during reactivation can lead to postherpetic neuralgia (PHN). For PHN of the first division of the fifth cranial nerve (ophthalmic division of the trigeminal ganglion), there is evidence of inflammatory change in the ganglion and adjacent ocular neural structures. First division trigeminal nerve PHN can prove to be difficult and sometimes even impossible to manage despite the use of a wide range of conservative measures, including anticonvulsant and antidepressant medication. Steroids have been shown to play an important role by suppressing neural inflammatory processes. We therefore chose the trigeminal ganglion as an interventional target for an 88‐year‐old woman with severe ophthalmic division PHN after she failed to respond to conservative treatment.

Methods

Under fluoroscopic guidance, a trigeminal ganglion nerve block was performed with lidocaine combined with dexamethasone. A retrobulbar block with lidocaine and triamcinolone settled residual oculodynia.

Results

At 1‐year follow‐up, the patient remained pain free and did not require analgesic medication.

Conclusion

To our knowledge, this is the first reported case of ophthalmic division PHN successfully treated with a combination of trigeminal ganglion and retrobulbar nerve block using a local anesthetic agent and steroid for central and peripheral neural inflammatory processes.
Shade tolerance and herbivory are associated with RGR of tree species via different functional traits
Authors: Salgado‐Luarte C. , Gianoli E.
Published: December 2016

Relative growth rate (RGR) plays an important role in plant adaptation to the light environment through the growth potential/survival trade‐off. RGR is a complex trait with physiological and biomass allocation components. It has been argued that herbivory may influence the evolution of plant strategies to cope with the light environment, but little is known about the relation between susceptibility to herbivores and growth‐related functional traits.

Here, we examined in 11 evergreen tree species from a temperate rainforest the association between growth‐related functional traits and (i) species’ shade‐tolerance, and (ii) herbivory rate in the field. We aimed at elucidating the differential linkage of shade and herbivory with RGR via growth‐related functional traits.

We found that RGR was associated negatively with shade‐tolerance and positively with herbivory rate. However, herbivory rate and shade‐tolerance were not significantly related. RGR was determined mainly by photosynthetic rate (Amax) and specific leaf area (SLA). Results suggest that shade tolerance and herbivore resistance do not covary with the same functional traits. Whereas shade‐tolerance was strongly related to Amax and to a lesser extent to leaf mass ratio (LMR) and dark respiration (Rd), herbivory rate was closely related to allocation traits (SLA and LMR) and slightly associated with protein content.

The effects of low light on RGR would be mediated by Amax, while the effects of herbivory on RGR would be mediated by SLA. Our findings suggest that shade and herbivores may differentially contribute to shape RGR of tree species through their effects on different resource‐uptake functional traits.
Sourcing Information Security Operations: The Role of Risk Interdependency and Competitive Externality in Outsourcing Decisions
Authors: Cezar Asunur , Cavusoglu Huseyin , Raghunathan Srinivasan
Published: December 2016

Firms are increasingly outsourcing information security operations to managed security service providers (MSSPs). Cost reduction and quality (security) improvement are often mentioned as motives for outsourcing information security, and these are also the frequently cited reasons for outsourcing traditional information technology (IT) functions, such as software development and maintenance. In this study, we present a different explanation—one based on interdependent risks and competitive externalities associated with IT security—for firms' decisions to outsource security. We show that in the absence of competitive externalities and interdependent risks, a firm will outsource security if and only if the MSSP offers a quality advantage over in‐house operations, which is consistent with the conventional explanation for security outsourcing. However, when security risks are interdependent and breaches impose competitive externalities, although firms still have stronger incentive to outsource security if the MSSP offers a higher quality in terms of preventing breaches than in‐house management, a quality advantage of MSSP over in‐house management is neither a prerequisite for a firm to outsource security nor a guarantee that a firm will. In addition to MSSP quality, the type of externality (positive or negative), the degree of externality, whether outsourcing increases or decreases risk interdependency, and the breach characteristics determine firms' sourcing decisions. When security breaches impose a positive externality, the incentive to outsource is enhanced if the MSSP decreases the risk interdependency and diminished if the MSSP increases this interdependency. A negative externality has the opposite effect on firms' incentives to outsource. A high demand spillover to a competitor, together with a high loss in industry demand because of a security breach, enhances these incentives to outsource security operations when the externality is negative. Finally, we extend our base model in several dimensions and show that our main results regarding the impact of interdependent risks and competitive externalities on sourcing decisions are robust and generalizable to different specifications.
Volatile compounds released by maize grains and silks in response to infection by Fusarium verticillioides and its association with pathogen resistance
Authors: Fauguel C. M. , Campos Bermudez V. A. , Iglesias J. , Fernandez M. , Farroni A. , Andreo C. S. , Presello D. A.
Published: December 2016

Many plants respond to fungal infections by producing and/or emitting a specific blend of oxylipins, some of them through the lipoxygenase (LOX) pathway. In vitro bioassays revealed that volatiles from silks and grains of a set of six maize genotypes with variable resistance to Fusarium verticillioides affected fungal growth in different ways. Analyses by solid phase microextraction and GC‐MS showed different volatile profiles in silks and grains of each genotype. Susceptible genotypes with higher concentrations of precursor polyunsaturated fatty acids produced more volatiles, mainly C9 compounds, in comparison to moderately resistant ones. Real‐time PCR from several lipoxygenase transcripts revealed that levels of gene expression depended on the genotype and the inoculation level and suggested that F. verticillioides could use compounds from the 9‐LOX pathway to promote infection in grains. On the other hand, volatiles produced by the 13‐LOX pathway were more important in moderately resistant genotypes and could be associated to field resistance. Results from this set of genotypes indicate that LOX‐regulated volatile compounds might be important in F. verticillioides infection and should be targeted in further research to understand disease resistance.
Estimation and Inference Procedures for Semiparametric Distribution Models with Varying Linear‐Index
Authors: Huang Ming‐Yueh , Chiang Chin‐Tsang
Published: December 2016

More flexible semiparametric linear‐index regression models are proposed to describe the conditional distribution. Such a model formulation captures varying effects of covariates over the support of a response variable in distribution, offers an alternative perspective on dimension reduction and covers a lot of widely used parametric and semiparameteric regression models. A feasible pseudo likelihood approach, accompanied with a simple and easily implemented algorithm, is further developed for the mixed case with both varying and invariant coefficients. By justifying some theoretical properties on Banach spaces, the uniform consistency and asymptotic Gaussian process of the proposed estimator are also established in this article. In addition, under the monotonicity of distribution in linear‐index, we develop an alternative approach based on maximizing a varying accuracy measure. By virtue of the asymptotic recursion relation for the estimators, some of the achievements in this direction include showing the convergence of the iterative computation procedure and establishing the large sample properties of the resulting estimator. It is noticeable that our theoretical framework is very helpful in constructing confidence bands for the parameters of interest and tests for the hypotheses of various qualitative structures in distribution. Generally, the developed estimation and inference procedures perform quite satisfactorily in the conducted simulations and are demonstrated to be useful in reanalysing data from the Boston house price study and the World Values Survey.
SHOT conference report 2016: serious hazards of transfusion – human factors continue to cause most transfusion‐related incidents
Authors: Bolton‐Maggs P. H. B.
Published: December 2016

The Annual SHOT Report for incidents reported in 2015 was published on 7 July at the SHOT symposium. Once again, the majority of reports (77·7%) were associated with mistakes (‘human factors’). Pressures and stress in the hospital environment contributed to several error reports. There were 26 deaths where transfusion played a part, one due to haemolysis from anti‐Wra (units issued electronically). The incidence of haemolysis due to this antibody has increased in recent years. Transfusion‐associated circulatory overload is the most common contributor to death and major morbidity. Reports of delays to transfusion have increased, some caused by the failure of correct patient identification. There were seven ABO‐incompatible red cell transfusions (one death) with an additional six to allogeneic stem cell transplant recipients. Near‐miss reporting and analysis is useful and demonstrated nearly 300 instances of wrong blood in tube, which could have resulted in ABO‐incompatible transfusion had the error not been detected. Errors with anti‐D immunoglobulin continue, and preliminary data from the new survey of new anti‐D found in pregnancy has shown that sensitisation occurs in some women even with apparently ‘ideal’ care. For the first time, the SHOT report now incorporates a chapter on donor events.
The Effect of Implementing a Feed-in Tariff in Abu Dhabi UAE
Authors: Sasaki Daisuke , Matsuo Gun , Khatib Sameh El , Nakayama Mikiyasu
Published: December 2016

Although most countries in the world have been trying to introduce renewable energy into their power supplies to address issues related to the environment and energy security, the Middle East has the lowest overall renewable energy capacity in the world. However, there is currently a trend of accelerating renewable energy deployment with increased investment in the region for the purposes of improving energy security and independence and promoting long-term social and economic benefits. This study aims to examine the impact of implementing a feed-in tariff (FiT) in Abu Dhabi, United Arab Emirates. After a simulated test, it was found that the levelized cost of electricity (LCOE) and the current average unit cost of electricity were considerably divergent. That is to say, a large extra cost is incurred in order to deploy renewable energy in Abu Dhabi. In this context, the effectiveness of implementing a FiT in Abu Dhabi is confirmed. Furthermore, an estimation of the size of the renewable energy surcharge indicated that the impact of implementing a FiT would be enormous. For example, if the target rate of deploying renewable energy is set at 7%, a renewable energy surcharge equivalent to approximately one third of the total turnover of the electricity sector should be additionally imposed. It follows that the electricity rate will be raised by about thirty percent on average, unless subsidies are provided by the government.
In vivo deep two‐photon imaging of neural circuits with the fluorescent Ca2+ indicator Cal‐590
Authors: Tischbirek Carsten H. , Birkner Antje , Konnerth Arthur
Published: December 2016

In vivo two‐photon Ca2+ imaging has become an effective approach for the functional analysis of neuronal populations, individual neurons and subcellular neuronal compartments in the intact brain. When imaging individually labelled neurons, depth penetration can often reach up to 1 mm below the cortical surface. However, for densely labelled neuronal populations, imaging with single‐cell resolution is largely restricted to the upper cortical layers in the mouse brain. Here, we review recent advances of deep two‐photon Ca2+ imaging and the use of red‐shifted fluorescent Ca2+ indicators as a promising strategy to increase the imaging depth, which takes advantage of reduced photon scattering at their long excitation and emission wavelengths. We describe results showing that the newly introduced fluorescent Ca2+‐sensitive dye Cal‐590 can be used to record in vivo neuronal activity in isolated cortical neurons and in neurons within populations in depths of up to 900 μm below the pial surface. Thus, the new approach allows the comprehensive functional mapping of all six cortical layers of the mouse brain. Specific features of Cal‐590‐based in vivo Ca2+ two‐photon imaging include a good signal‐to‐noise ratio, fast kinetics and a linear dependence of the Ca2+ transients on the number of action potentials. Another area of application is dual‐colour imaging by combining Cal‐590 with other, shorter wavelength Ca2+ indicators such as OGB‐1. Overall, Cal‐590‐based two‐photon microscopy emerges as a promising tool for the recording of neuronal activity at depths that were previously inaccessible to functional imaging of neuronal circuits.

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Periodic Signal Tracking for Lightly Damped Systems
Authors: van der Maas Rick , Singh Tarunraj , Steinbuch Maarten
Published: December 2016

The focus of this paper is on the development of time-delay filters to accomplish tracking of periodic signals with zero phase errors. The class of problems addressed include systems whose dynamics are characterized by lightly damped modes. A general approach for the zero-phase tracking of periodic inputs is presented followed by an illustration of single harmonic tracking of underdamped second-order systems with relative degree two. A general formulation of the approach is then posed for higher-order systems and systems including zeros. The paper concludes with the illustration of enforcing constraints to desensitize the time-delay filter to uncertainties in the location of the poles of the system and forcing frequencies. A numerical practical design case based on a medical X-ray system is used to illustrate the potential of the proposed technique.
Design of a High Bandwidth Nonresonant Tertiary Motion Generator for Elliptical Vibration Texturing
Authors: Chen Keyu , Si Chang , Guo Ping
Published: December 2016

This paper presents the design and characteristics of a new two-dimensional nonresonant tertiary motion generator which is based on the flextensional structure. A tool holder connects two perpendicularly placed flextensional actuators with flexure hinges which decouple the motion outputs from the two actuators. Piezoelectric stacks, which are preloaded through precision screws, are used to provide input displacements. By balancing the requirements of driving current, stiffness, and the displacement amplification ratio, the proposed design is targeted to operate at above 10 kHz with two-dimensional vibrations amplitude of 10 μm in each direction. Technical difficulties in driving a nonresonant mode piezoelectric actuator at a high frequency are discussed. The solutions and optimization procedures are presented in this paper. The design is optimized by finite-element simulation; and the results are presented and verified by our prototype design.
An Optimal Ensemble Empirical Mode Decomposition Method for Vibration Signal Decomposition
Authors: Du Shi-Chang , Liu Tao , Huang De-Lin , Li Gui-Long
Published: December 2016

The vibration signal decomposition is a critical step in the assessment of machine health condition. Though ensemble empirical mode decomposition (EEMD) method outperforms fast Fourier transform (FFT), wavelet transform, and empirical mode decomposition (EMD) on nonstationary signal decomposition, there exists a mode mixing problem if the two critical parameters (i.e., the amplitude of added white noise and the number of ensemble trials) are not selected appropriately. A novel EEMD method with optimized two parameters is proposed to solve the mode mixing problem in vibration signal decomposition in this paper. In the proposed optimal EEMD, the initial values of the two critical parameters are selected based on an adaptive algorithm. Then, a multimode search algorithm is explored to optimize the critical two parameters by its good performance in global and local search. The performances of the proposed method are demonstrated by means of a simulated signal, two bearing vibration signals, and a vibration signal in a milling process. The results show that compared with the traditional EEMD method and other improved EEMD method, the proposed optimal EEMD method automatically obtains the appropriate parameters of EEMD and achieves higher decomposition accuracy and faster computational efficiency.
The Effect of Compression Force Uniformity on Bipolar Tissue Welding
Authors: Li Xiaoran , Borduin Russel , Chen Roland K. , Li Wei
Published: December 2016

Bipolar forceps are a type of electrosurgical device (ESD) widely used for tissue welding in modern surgeries. ESDs have many advantages over traditional surgical tools including reduced blood loss, improved efficiency, and lower surgeon fatigue. However, these devices suffer from tissue sticking and damage due to overheating which leads to poor tissue joint quality. The problem is potentially caused by uneven power distribution due to nonuniform compression applied by the bipolar forceps. In this study, the effect of compression force uniformity was investigated with an experimental setup to achieve a uniform and consistent compression force at the jaws of bipolar forceps. Comparative tissue welding experiments were conducted under both uniform and nonuniform compression force conditions with tissue mimicking material. In situ welding process parameters including compression force, electrical voltage, and current were collected and analyzed to understand the effect of compression force uniformity. The results indicate that tissue impedance is lower due to increased tool–tissue contact area; the electrical power is initially higher during the first few milliseconds of welding. The experimental device developed in this study provides an important platform to understand the difference of tissue welding process under uniform and nonuniform compression force conditions.
The Spherical Equivalent of Bresse's Circles: The Case of Crossed Double-Crank Linkages
Authors: Figliolini Giorgio , Angeles Jorge
Published: December 2016

The subject of Bresse's circles is classical in the kinematics of planar mechanisms. These are the loci of the coupler points that exhibit either zero normal or zero tangential acceleration. Described in this paper is the construction of the spherical equivalent of Bresse's circles, which take the form of an inflexion spherical cubic and a Thales ellipse, respectively. An algorithm is developed to produce these loci for the case of the spherical antiparallelogram. As a byproduct, the corresponding polodes and their evolutes are obtained.
Large-Scale Detached-Eddy Simulation Analysis of Stall Inception Process in a Multistage Axial Flow Compressor
Authors: Yamada Kazutoyo , Furukawa Masato , Tamura Yuki , Saito Seishiro , Matsuoka Akinori , Nakayama Kentaro
Published: December 2016

This paper describes the flow mechanisms of rotating stall inception in a multistage axial flow compressor of an actual gas turbine. Large-scale numerical simulations of the unsteady have been conducted. The compressor investigated is a test rig compressor that was used in the development of the Kawasaki L30A industrial gas turbine. While the compressor consists of a total of 14 stages, only the front stages of the compressor were analyzed in the present study. The test data show that the fifth or sixth stages of the machine are most likely the ones leading to stall. To model the precise flow physics leading to stall inception, the flow was modeled using a very dense computational mesh, with several million cells in each passage. A total of 2 × 109 cells were used for the first seven stages (3 × 108 cells in each stage). Since the mesh was still not fine enough for large-eddy simulation (LES), a detached-eddy simulation (DES) was used. Using DES, a flow field is calculated using LES except in the near-wall where the turbulent eddies are modeled by Reynolds-averaged Navier–Stokes. The computational resources required for such large-scale simulations were still quite large, so the computations were conducted on the K computer (RIKEN AICS in Japan). Unsteady flow phenomena at the stall inception were analyzed using data mining techniques such as vortex identification and limiting streamline drawing with line integral convolution (LIC) techniques. In the compressor studied, stall started from a separation on the hub side rather than the commonly observed leading-edge separation near the tip. The flow phenomenon first observed in the stalling process is the hub corner separation, which appears in a passage of the sixth stator when approaching the stall point. This hub corner separation grows with time, and eventually leads to a leading-edge separation on the hub side of the stator. Once the leading-edge separation occurs, it rapidly develops into a rotating stall, causing another leading-edge separation of the neighboring blade. Finally, the rotating stall spreads to the upstream and downstream blade rows due to its large blockage effect.
Plasma-assisted atomic layer deposition of HfNx: Tailoring the film properties by the plasma gas composition
Authors: Karwal S. , Williams B. L. , Niemelä J.-P. , Verheijen M. A. , Kessels W. M. M. , Creatore M.
Published: December 2016

The authors synthesized HfNx (x ≥ 1) thin films by plasma-assisted atomic layer deposition at stage temperatures of 350–450 °C by using the high-thermal-stability CpHf(NMe2)3 monomer as Hf precursor and either H2 plasma or N2 plasma as coreactant. Most notably, the selection of the plasma gas composition enabled us to tune the film properties: films fabricated using N2 plasma led to the formation of highly resistive and amorphous Hf3N4 films (6 × 102 Ω cm), while the use of the strongly reducing H2 plasma generated conductive (resistivity of 6 × 10−1 Ω cm) films with the signature of the δ-HfN fcc crystal structure. Via x-ray photoelectron spectroscopy, the authors observed that the use of the H2 plasma facilitates the reduction of the oxidation state of Hf from Hf4+ to Hf3+. This result was corroborated by the simultaneous increase in the free carrier absorption observed in the infrared range via spectroscopic ellipsometry. The δ-HfNx films fabricated via the present route are promising as highly reflective back contacts for thin films solar cells, Cu diffusion barriers, and as a gate metal for metal–oxide–semiconductor capacitors, provided that the resistivity values can be further decreased by suppressing the formation of the resistive Hf2ON2 impurity phase and grain-boundary scattering of the charge carriers.
Atomic layer deposition of HfO2 using HfCp(NMe2)3 and O2 plasma
Authors: Sharma Akhil , Longo Valentino , Verheijen Marcel A. , Bol Ageeth A. , Kessels W. M. M. (Erwin)
Published: December 2016

HfO2 thin films were prepared by plasma-enhanced atomic layer deposition using a cyclopentadienyl-alkylamido precursor [HfCp(NMe2)3, HyALD™] and an O2 plasma over a temperature range of 150–400 °C at a growth per cycle around 1.1 Å/cycle. The high purity of the films was demonstrated by x-ray photoelectron spectroscopy and elastic recoil detection analyses which revealed that by increasing the deposition temperature from 200 to 400 °C, the atomic concentrations of residual carbon and hydrogen reduced from 1.0 to <0.5 at. % and 3.4 to 0.8 at. %, respectively. Moreover, Rutherford backscattering spectroscopy studies showed an improvement in stoichiometry of HfO2 thin films with the increase in deposition temperature, resulting in Hf/O ratio close to ∼0.5 at 400 °C. Furthermore, grazing incidence x-ray diffraction measurements detected a transition from amorphous at the deposition temperature of 300 °C to fully polycrystalline films at 400 °C, consisting of a mixture of monoclinic, tetragonal, and cubic phases. Finally, the surface morphology and conformality of HfO2 thin films studied by atomic force microscopy and transmission electron microscopy are also reported.
Low-temperature-atomic-layer-deposition of SiO2 using various organic precursors
Authors: Ahn Sehyoung , Kim Yunsu , Kang Sangyeoul , Im Kivin , Lim Hanjin
Published: December 2016

The low-temperature-atomic layer deposition (ALD) of SiO2 has a lot of applications in semiconductor devices. Moreover, it is hard to control the conformality and reproducibility in high aspect ratio structures. In this study, the authors investigated the ALD behaviors of SiO2 using various precursors in both 2D and 3D structures. It was shown that a high level of thickness control and perfect surface coverage techniques can be achieved even on a 200:1 aspect ratio structure at a low growth temperature of 250 °C by using bis(ethyl-methylamino)silane.
A Pedagogical Model for the Doppler Effect with Application to Sources with Constant Accelerations
Authors: Kaura Lakshya P. S. , Pathak Praveen
Published: December 2016

Kinematic models are often very useful. The back and forth throw of a ball between two ice skaters may help us appreciate the meson exchange theory of Yukawa. If the skaters throw the balls at each other, they move backward, which is equivalent to a repulsive force between them. On the other hand, if they snatch the ball from each other, the result will be akin to an equivalent attractive force between them. Such illustrative models may help us understand advanced concepts.
Bound states of atomic Josephson vortices
Authors: Qadir Muhammad Irfan , Tahir Usama
Published: December 2016

We study the existence and stability of the bound state Josephson vortices solution in two parallel quasi one-dimensional coupled Bose–Einstein condensates. The system can be elucidated by linearly coupled Gross–Pitaevskii equations. The purpose of this study is to investigate the effects of altering the strength of coupling between the two condensates over the stability of the bound-state Josephson vortices. It is found that the stability of bound-state Josephson vortices depends on the value of coupling strength. However, at a critical value of coupling parameter, the Josephson vortices solution transforms into a coupled dark soliton.
Overview of recent advances performed in the study of atomic structures and radiative processes for the lowest ionization stages of heavy elements
Authors: Quinet Pascal
Published: December 2016

During the past 20 years, part of our work has been focused on the study of the atomic structure and the determination of radiative parameters in neutral and slightly ionized heavy atoms (Z ≥ 37). These elements attracted little previous interest because of the complexity of their electronic structures, the poor knowledge of their spectra, and the difficulty to perform experimental measurements. They present, however, great interest in the development of other scientific areas, such as astrophysics and plasma physics. In this paper, we give an overview of the recent progress performed by the group of Atomic Physics and Astrophysics at Mons University (Belgium) in the theoretical modelling and the experimental analysis of such heavy elements. We also discuss some applications of the atomic data obtained in our work for the interpretation of the spectra observed from astrophysical and laboratory plasmas.