bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast quantitative 3D ultrashort echo time MRI of cortical bone using extended cones sampling
Authors: Wan Lidi , Zhao Wei , Ma Yajun , Jerban Saeed , Searleman Adam C. , Carl Michael , Chang Eric Y. , Tang Guangyu , Du Jiang
Published: March 2019

Purpose

To investigate the effect of stretching sampling window on quantitative 3D ultrashort TE (UTE) imaging of cortical bone at 3 T.

Methods

Ten bovine cortical bone and 17 human tibial midshaft samples were imaged with a 3T clinical MRI scanner using an 8‐channel knee coil. Quantitative 3D UTE imaging biomarkers, including T1, , magnetization transfer ratio and magnetization transfer modeling, were performed using radial or spiral Cones sampling trajectories with various durations. Errors in UTE‐MRI biomarkers as a function of sampling time were evaluated using radial sampling as a reference standard.

Results

For both bovine and human cortical bone samples, no significant differences were observed for all UTE biomarkers (single‐component , bicomponent and relative fractions, T1, magnetization transfer ratio, and magnetization transfer modeling of macromolecular fraction) for spiral sampling windows of 992 µs to 1600 µs compared with a radial sampling window of 688 µs.

Conclusion

The total scan time can be reduced by 76% with quantification errors less than 5%. Quantitative UTE‐MRI techniques can be greatly accelerated using longer sampling windows without significant quantification errors.
Trendbericht Organische Chemie
Authors: Andexer Jennifer N. , Beifuss Uwe , Beuerle Florian , Brasholz Malte , Breinbauer Rolf , Ernst Martin , Gulder Tobias A. M. , Kath‐Schorr Stephanie , Kordes Markus , Lehmann Matthias , Lindel Thomas , Lüdeke Steffen , Luy Burkhard , Mantel Marvin , Mück‐Lichtenfeld Christian , Muhle‐Goll Claudia , Narine Arun , Niemeyer Jochen , Pfau Roland , Pietruszka Jörg , Schaschke Norbert , Senge Mathias O. , Straub Bernd F. , Werner Thomas , Werz Daniel B. , Winter Christian
Published: March 2019

Rekordwert bei der Umwandlung von Sonnenlicht in Tandemsolarzellen – längstes Acen – X‐förmiges Porphyrintetramer – hochpotenter Influenza‐Neuramidinidase‐Inhibitor – Totalsynthese von Isoplagiochin D – chirales Phosphat zur stereoselektiven Katalyse – mechanochemische Direktsynthese einfacher Alkoxysilane aus Silicium und Alkoholen.
Plattformen als Geschäftsmodelle
Authors: von Delft Stephan , van der Veen Gijs
Published: March 2019

Interaktive Netzwerke werden sich zu einem wesentlichen Baustein im Geschäft von Chemieunternehmen entwickeln. Dafür müssen Anbieter umdenken.
Vierzehnte J‐NOST‐Konferenz in Hyderabad
Authors: Memmel Philipp
Published: March 2019

Der National Organic Symposium Trust (NOST) organisiert in regelmäßigen Abständen Symposien im Fachgebiet der Organischen Chemie an verschiedenen Orten in Indien. Anfang Dezember 2018 fand die 14. NOST Conference for Research Scholars (J‐NOST) am CSIR‐Indian Institute of Chemical Technology in Hyderabad statt.
Multiobjective optimization‐based design of stabilizing piles in earth slopes
Authors: Tang Huiming , Gong Wenping , Wang Liangqing , Juang C. Hsein , Martin James R. , Li Changdong
Published: March 2019

Though the technology of using stabilizing piles to prevent landsliding is not new, the design of such piles with a meaningful optimization framework has been rarely reported. In this paper, a multiobjective optimization‐based framework for design of stabilizing piles is presented, in which both reinforcement effectiveness and cost efficiency could be explicitly considered. The design parameters considered in the proposed design framework are the pile parameters, including pile diameter, spacing, length, and position, and the design objectives considered are the reinforcement effectiveness and cost efficiency. The design of stabilizing piles is then implemented as a multiobjective optimization problem. In that the desire to maximize the reinforcement effectiveness and that to maximize the cost efficiency are two conflicting objectives, the output of this multiobjective optimization will be a Pareto front that depicts a trade‐off between these two design objectives. With the obtained Pareto front, an informed decision regarding the design of stabilizing piles is reached. The effectiveness and significance of the proposed multiobjective optimization‐based design framework for stabilizing piles are demonstrated through two illustrative examples: one is the design of stabilizing piles in a one‐layer earth slope and the other the design of stabilizing piles in a two‐layer earth slope. Further, parametric analyses are conducted to investigate the influences of the pile design parameters on the stability of reinforced slopes.
Iron Status and Metabolically Unhealthy Obesity in Prepubertal Children
Authors: Suárez‐Ortegón Milton Fabian , Echeverri Isabella , Prats‐Puig Anna , Bassols Judit , Carreras‐Badosa Gemma , López‐Bermejo Abel , Fernández‐Real Jose Manuel
Published: March 2019

Objective

This study aimed to evaluate the association of metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) with iron status markers in prepubertal children.

Methods

Three hundred twelve prepubertal children with overweight and obesity from a pediatric general Spanish population were evaluated. MHO and MUO were defined as obesity with the absence or presence of metabolic syndrome components. Phenotypes of metabolically healthy overweight including obesity (MHOV) and metabolically unhealthy overweight including obesity (MUOV) were also studied and defined using the same criteria. Serum ferritin, transferrin, and blood hemoglobin levels were evaluated.

Results

Prevalence rates of MHOV and MHO were 35% (n = 111/312) and 27.1% (n = 42/155), respectively. Ferritin and hemoglobin levels were higher in children with MUOV versus MHOV (P < 0.05). MUO was positively associated with ferritin (beta [95% CI] = 0.43 [0.05 to 0.81]) and hemoglobin levels (0.43 [0.05 to 0.81]). These associations remained significant independently of age, sex, C‐reactive protein, physical activity, and BMI/waist z scores in bivariate linear regression models. In multivariable models, transaminase levels attenuated the association of MUO with ferritin and hemoglobin levels (P > 0.05).

Conclusions

MUOV and MUO are associated with higher ferritin and hemoglobin levels in prepubertal children affected by overweight and obesity. Increased circulating ferritin in MUO might be influenced by liver injury.
A comparative study on wear and friction characteristics of phenolic composite coatings filled with different morphologies ZnO
Authors: Wu Liangfei , Zhang Zhaozhu , Yang Mingming , Yuan Junya , Men Xuehu , Guo Fang
Published: March 2019

In this paper, different morphologies ZnO (disk‐like, rod‐like, and nanoparticles) were introduced into phenolic composite coatings to comparatively investigate the tribological properties. The structural and morphological characterization was conducted with Raman spectroscopy, X‐ray diffraction, and scanning electron microscopy. The tribological performances of composite coatings were evaluated using ring‐on‐block tester under dry condition at room temperature. Experimental results indicated that composite coatings filled with 1 wt% ZnO micro‐disks possessed the optimal tribological performances. It was attributed to the strong interfacial interaction between ZnO micro‐disks and phenolic matrix induced by their specific polar structure. Moreover, different loads and sliding speeds were employed to further evaluate the tribological performances of ZnO micro‐disks/phenolic composite coatings. The outcome revealed that ZnO micro‐disks were potential anti‐wear fillers under harsh condition.
A heuristic method for modeling the initial pressure drop in melt filtration using woven screens in polymer recycling
Authors: Pachner Sophie , Aigner Michael , Miethlinger Jürgen
Published: March 2019

This paper addresses the use of heuristic optimization algorithms to generate generally valid analytic equations for estimating the initial pressure drop of square and Dutch woven screens in polymer recycling. We present a mathematical description of the isothermal initial pressure drop of non‐Newtonian polymer melt flows through woven screens without the need for numerical methods. We first performed numerical CFD simulations to create a set of 9,000 physically independent modeling set‐ups as a basis for heuristic modeling. Then, we applied symbolic regression based on genetic programming to develop pecScreen models, achieving coefficients of determination R2 > 0.9995. For verification of our models, we performed experiments using both virgin and slightly contaminated in‐house and post‐industrial recycling materials. The experimentally determined data are in good agreement with the approximation results, which yielded a coefficient of determination R2 of 0.926. Our modeling approach, the accuracy of which we have proven, allows fast and stable computational modeling of the initial pressure drop of polymer melt flows through woven screens. POLYM. ENG. SCI., 59:1105–1113 2019. © 2019 The Authors. Polymer Engineering & Science published by Wiley Periodicals, Inc. on behalf of Society of Plastics Engineers.
Are B chromosomes useful for crop improvement?
Authors: Jones Neil , Ruban Alevtina
Published: March 2019

Societal Impact Statement

Ensuring the sustainable production of food within the context of an increasing world population is a huge challenge facing humankind. Here we review the existence of additional, non‐essential chromosomes, known as B chromosomes, and consider their potential usefulness for crop improvement. These enigmatic chromosomes have long fascinated scientists and although their origin and function in plants is somewhat obscure, new research is beginning to shed light on these mysterious chromosomes. This work suggests that B chromosomes may be useful for crop improvement, particularly in grasses, where they show promise as a mechanism to introduce new genes, which could potentially help us to produce more efficient crops.

Summary

The question of the usefulness of supernumerary B chromosomes (Bs) has long fascinated cytogeneticists. Since their discovery in 1907 thousands of species with Bs have been discovered, but their function in the genetics system remains enigmatic, from their origin, evolution, and adaptive significance, as well as their molecular structure and organization. New research is beginning to answer some of these tantalizing questions. Here, we summarize the known data and conclude that Bs are potentially useful, but only in a few known cases, especially in the grasses, and notably in terms of their engineering as plant artificial chromosomes (mini‐chromosomes) to carry whole suites of transgenes outside of, and free from interference with, the normal genome.
Multi‐criteria decision analysis for environmental remediation: Benefits, challenges, and recommended practices
Authors: Havranek Timothy J.
Published: March 2019

Multi‐criteria decision analysis (MCDA) is a social process and analytical framework that has been utilized since the late 1960s and widely applied in industries other than the remediation field. Given the complex features of remediation projects, MCDA holds the promise of providing considerable value to the remediation industry. However, its value has yet to be fully realized. This paper describes the potential benefits of MCDA to the environmental remediation industry, the factors that may limiting its use in this industry, and the MCDA process in general. The MCDA process description includes recommended practices for including stakeholder values and objectives and for performing stochastic MCDA. Lastly, the paper includes recommendations for enhancing stakeholder communications within the MCDA process.
Visual Quantitative Detection of Circulating Tumor Cells with Single‐Cell Sensitivity Using a Portable Microfluidic Device
Authors: Abate Mahlet Fasil , Jia Shasha , Ahmed Metages Gashaw , Li Xingrui , Lin Li , Chen Xiaoqian , Zhu Zhi , Yang Chaoyong
Published: March 2019

Immunocytological technologies, molecular technologies, and functional assays are widely used for detecting circulating tumor cells (CTCs) after enrichment from patients' blood sample. Unfortunately, accessibility to these technologies is limited due to the need for sophisticated instrumentation and skilled operators. Portable microfluidic devices have become attractive tools for expanding the access and efficiency of detection beyond hospitals to sites near the patient. Herein, a volumetric bar chart chip (V‐Chip) is developed as a portable platform for CTC detection. The target CTCs are labeled with aptamer‐conjugated nanoparticles (ACNPs) and analyzed by V‐Chip through quantifying the byproduct (oxygen) of the catalytic reaction between ACNPs and hydrogen peroxide, which results in the movement of an ink bar to a concentration‐dependent distance for visual quantitative readout. Thus, the CTC number is decoded into visually quantifiable information and a linear correlation can be found between the distance moved by the ink and number of cells in the sample. This method is sensitive enough that a single cell can be detected. Furthermore, the clinical capabilities of this system are demonstrated for quantitative CTC detection in the presence of a high leukocyte background. This portable detection method shows great potential for quantification of rare cells with single‐cell sensitivity for various applications.
Supported Single Atoms as New Class of Catalysts for Electrochemical Reduction of Carbon Dioxide
Authors: Cheng Yi , Yang Shize , Jiang San Ping , Wang Shuangyin
Published: March 2019

Carbon dioxide (CO2) emitted from excess consumption of fossil fuels leads to the rise of CO2 concentrations in the atmosphere. One of the most attractive solutions to cut CO2 emission is the electrochemical reduction of CO2 to produce fuels and build a low carbon emission economy. However, the electrochemical CO2 reduction reaction (CO2RR) is a great challenge due to the activation of the highly stable, linear CO2 molecules, and the process involves proton‐coupled multi‐electron transfer with a high energy barrier. Thus, it is critical to develop efficient and highly stable catalyst materials for CO2RR. Nanoparticle‐based electrocatalysts have been extensively investigated, but the broad size distribution not only limits their activity due to the size‐dependent catalytic properties, but also constrains the selectivity and leads to undesired side reactions. Single‐atom catalysts (SACs), a rising star in the catalytic area, can combine the merits of heterogeneous and homogeneous catalysts, offering outstanding opportunities for CO2RR. The advent of SACs for CO2RR has attracted enormous attention recently, and great effort has been devoted into the area and significant advancements have been achieved in recent years. Here, this mini review updates the development of SACs for CO2RR, and their opportunities and challenges are discussed.
My Culture Is Not a Costume: Institutional Practices and Racism
Authors: Beatty Cameron C. , Boettcher Michelle L.
Published: March 2019

This chapter critically considers the roles of racist traditions and actions in promoting and perpetuating racism, power, privilege, and oppression in fraternity and sorority life.
Property Functions of Whiteness: Counter‐Narrative Analysis of Teach For America and Their Partnership With Black and Latinx Fraternities and Sororities
Authors: Muñoz Susana M. , Vasquez Heilig Julian , Del Real Manuel
Published: March 2019

In this chapter, the authors consider the controversy surrounding Teach For America and their alliance with Black and Latinx fraternities and sororities, and conclude with suggestions for community service and best practices for these organizations.
Sorority Life Reimagined: Deaf Culture and Mainstream Sorority life
Authors: Stapleton Lissa D. , Nicolazzo Z
Published: March 2019

This chapter explores the experiences of students in a Deaf sorority, highlighting the ways in which they resist audism through their social organization.
Smart Citizens in the Hackable City: On the Datafication, Playfulness, and Making of Urban Public Spaces Through Digital Art
Authors: de Lange Michiel , Synnes Kåre , Leindecker Gerald
Published: March 2019

This contribution explores concepts, approaches and technologies used to make urban public spaces more playful and artful. Through a variety of compelling narratives involving play and art it assists in the design of new cyberparks, public spaces where digitally mediated interactions are an inherent part. How can play and interactive art be used to strengthen urban public spaces by fostering citizen engagement and participation? We propose to not only utilise interactive media for designing urban (public) spaces, but also for social innovation for the benefit of citizens. in cyberparks. The contribution connects urbanity, play and games, as well as concepts of active and passive interactive digital art as part of trends towards pervasive urban interaction, gameful design and artification. We position this as an important part of developing human-centred smart cities where social capital is central, and where citizens engaging in play and art are prerequisites for sustainable communities. Using art, play and games to foster citizen engagement and collaboration is a means to develop social technologies and support the development of collective intelligence in cyberparks. This is studied in concrete cases, such as the Ice Castle in Luleå, Sweden and the Ars Electronica in Linz, from a multi-disciplinary stance involving interaction design, digital art, landscape design, architecture, and health proficiencies. We will analyse two cases of gameful design and one case of digital interactive art being used to address urban issues. Rezone the game is an interactive multimedia game developed to tackle vacancy in the city of Den Bosch in the Netherlands. The Neighbourhood is a board game developed to involve various stakeholders in making their neighbourhood using water as a collective resource.
Beyond the near-horizon limit: stringy corrections to heterotic black holes
Authors: Cano Pablo A. , Chimento Samuele , Meessen Patrick , Ortín Tomás , Ramírez Pedro F. , Ruipérez Alejandro
Published: March 2019

Abstract

We study the first-order in α

′
corrections to 4-charge black holes (with the Reissner-Nordström black hole as a particular example) beyond the near-horizon limit in the Heterotic Superstring effective action framework. The higher-curvature terms behave as delocalized sources in the equations of motion and in the Bianchi identity of the 3-form. For some charges, this introduces a shift between their values measured at the horizon and asymptotically. Some of these corrections and their associated charge shifts, but not all of them, can be canceled using appropriate SU(2) instantons for the heterotic gauge fields. The entropy, computed using Wald’s formula, is in agreement with the result obtained via microstate counting when the delocalized sources are properly taken into account.
D* polarization vs. $$ {R}_{D^{\left(\ast \right)}} $$ anomalies in the leptoquark models
Authors: Iguro Syuhei , Kitahara Teppei , Omura Yuji , Watanabe Ryoutaro , Yamamoto Kei
Published: March 2019

Abstract

Polarization measurements in

$$ \overline{B}\to {D}^{\left(\ast \right)}\tau \overline{\nu} $$

B
¯

→

D

∗

τ

ν
¯

are useful to check consistency in new physics explanations for the R

D
and

$$ {R}_{D^{*}} $$

R

D
*

anomalies. In this paper, we investigate the D
* and τ polarizations and focus on the new physics contributions to the fraction of a longitudinal D
* polarization (F

L

D *
), which is recently measured by the Belle collaboration F

L

D *
= 0.60 ± 0.09, in model-independent manner and in each single leptoquark model (R2, S1 and U1) that can naturally explain the

$$ {R}_{D^{\left(\ast \right)}} $$

R

D

∗

anomalies. It is found that ℬ(B

c

+
 → τ
+
ν) severely restricts deviation from the Standard Model (SM) prediction of F

L,SM

D *
= 0.46±0.04 in the leptoquark models: [0.43, 0.44], [0.42, 0.48], and [0.43, 0.47] are predicted as a range of F

L

D *
for the R2, S1, and U1 leptoquark models, respectively, where the current data of

$$ {R}_{D^{\left(\ast \right)}} $$

R

D

∗

is satisfied at 1σ level. It is also shown that the τ polarization observables can much deviate from the SM predictions. The Belle II experiment, therefore, can check such correlations between

$$ {R}_{D^{\left(\ast \right)}} $$

R

D

∗

and the polarization observables, and discriminate among the leptoquark models.
N = 2∗ phase transitions and holography
Authors: Russo Jorge G. , Widén Erik , Zarembo Konstantin
Published: March 2019

Abstract

We clarify the relationship between probe analysis of the supergravity dual and the large-N solution of the localization matrix model for the planar

$$ \mathcal{N}={2}^{\ast } $$

N
=

2
∗

super-Yang-Mills theory. A formalism inspired by supergravity allows us to systematically solve the matrix model at strong coupling. Quite surprisingly, we find that quantum phase transitions, known to occur in the

$$ \mathcal{N}={2}^{\ast } $$

N
=

2
∗

theory, start to be visible at the third order of the strong-coupling expansion and thus constitute a perturbative phenomenon on the string worldsheet.
Plane wave backgrounds and colour-kinematics duality
Authors: Adamo Tim , Casali Eduardo , Mason Lionel , Nekovar Stefan
Published: March 2019

Abstract

We consider perturbative gauge theory on a fixed Yang-Mills plane wave background, describing its Feynman rules in detail. Using these rules, the tree-level 4-point gluon amplitude is computed. As an application, we investigate whether some notion of colour-kinematics duality — a relation between the colour and kinematic constituents of the amplitude — holds on the plane wave background. Although the duality is obstructed, the obstruction has an interesting and highly-constrained structure. This plane wave version of colour-kinematics duality reduces on a flat background to the well-known identities underpinning the BCJ relations for colour-ordered partial amplitudes, and constrains representations of tree-level amplitudes beyond 4-points.
The Effect of Perioperative Iron Therapy in Acute Major Non‐cardiac Surgery on Allogenic Blood Transfusion and Postoperative Haemoglobin Levels: A Systematic Review and Meta‐analysis
Authors: Schack Anders , Berkfors Adam A. , Ekeloef Sarah , Gögenur Ismail , Burcharth Jakob
Published: March 2019

Background

Perioperative anaemia in relation to surgery is associated with adverse clinical outcomes. In an elective surgical setting, it is possible to optimize patients prior to surgery, often by iron supplementation with correction of anaemia. Possibilities for optimization prior to and during acute surgical procedures are limited. This review investigates whether iron treatment initiated perioperatively improves outcomes in patients undergoing major acute non‐cardiac surgery.

Method

This systematic review was performed using PubMed, EMBASE (Ovid) and Scopus to identify current evidence on iron supplementation in acute surgery. Primary outcomes were allogenic blood transfusion (ABT) rate and changes in haemoglobin. Secondary outcomes were postoperative mortality, length of stay (LOS), and postoperative complications. Iron was administered at latest within 24 h after end of surgery.

Results

Of the 5413 studies screened, four randomized controlled trials and nine observational cohort studies were included. Ten studies included patients with hip fractures. A meta‐analysis of seven studies showed a risk reduction of transfusion (OR = 0.35 CI 95% (0.20–0.63), p = 0.0004, I2 = 66%). No influence on plasma haemoglobin was found. Postoperative mortality was reduced in the iron therapy group in a meta‐analysis of four observational studies (OR 0.50 (CI 95% 0.26–0.96) p = 0.04). No effect was found on LOS, but a reduction in postoperative infection was seen in four studies.

Conclusions

This review examined perioperative iron therapy in acute major non‐cardiac surgery. IV iron showed a lower 30‐day mortality, a reduction in postoperative infections and a reduction in ABT largely due to the observational studies. The review primarily consisted of small observational studies and does not have the power to formally recommend this practice.
Non-static spherically symmetric spacetimes and their conformal Ricci collineations
Authors: Khan Fawad , Hussain Tahir , Bokhari Ashfaque Hussain , Akhtar Sumaira Saleem
Published: March 2019

For a perfect fluid matter, we present a study of conformal Ricci collineations (CRCs) of non-static spherically symmetric spacetimes. For non-degenerate Ricci tenor, a vector field generating CRCs is found subject to certain integrability conditions. These conditions are then solved in various cases by imposing certain restrictions on the Ricci tensor components. It is found that non-static spherically symmetric spacetimes admit 5, 6 or 15 CRCs. In the degenerate case, it is concluded that such spacetimes always admit infinite number of CRCs.
A Mixed approach of Deep Learning method and Rule-Based method to improve Aspect Level Sentiment Analysis
Authors: Ray Paramita , Chakrabarti Amlan
Published: March 2019

Social networks have changed the communication patterns significantly. Information available from different social networking sites can be well utilized for the analysis of users opinion. Hence, the organizations would benefit through the development of a platform, which can analyze public sentiments in the social media about their products and services to provide a value addition in their business process. Over the last few years, deep learning is very popular in the areas of image classification, speech recognition, etc. However, research on the use of deep learning method in sentiment analysis is limited. It has been observed that in some cases the existing machine learning methods for sentiment analysis fail to extract some implicit aspects and might not be very useful. Therefore, we propose a deep learning approach for aspect extraction from text and analysis of users sentiment corresponding to the aspect. A seven layer deep convolutional neural network (CNN) is used to tag each aspect in the opinionated sentences. We have combined deep learning approach with a set of rule-based approach to improve the performance of aspect extraction method as well as sentiment scoring method. We have also tried to improve the existing rule-based approach of aspect extraction by aspect categorization with a predefined set of aspect categories using clustering method and compared our proposed method with some of the state-of-the-art methods. It has been observed that the overall accuracy of our proposed method is 0.87 while that of the other state-of-the-art methods like modified rule-based method and CNN are 0.75 and 0.80 respectively. The overall accuracy of our proposed method shows an increment of 7–12% from that of the state-of-the-art methods.
The turbulent kinetic energy budget in a bubble plume
Authors: Lai Chris C. K. , Socolofsky Scott A.
Published: March 2019

We present the turbulent kinetic energy (t.k.e.) budget of a dilute bubble plume in its asymptotic state. The budget is derived from an experimental dataset of bubble plumes formed inside an unstratified water tank. The experiments cover both the adjustment phase and asymptotic state of the plume. The diameters $d$ of air bubbles are in the range 1–4 mm and the air void fraction $\unicode[STIX]{x1D6FC}_{g}$ is between 0.7 % and 1.8 %. We measured the three components of the instantaneous liquid velocity vector with a profiling acoustic Doppler velocimeter. From the experiments, we found the following inside the heterogeneous bubble core of the plume: (i) the probability density functions of the standardized liquid fluctuations are very similar to those of homogeneous bubble swarms rising with and without background liquid turbulence; (ii) the characteristic temporal frequency $f_{cwi}$ at which bubbles inject t.k.e. into the liquid agrees with the prediction $f_{cwi}=0.14u_{s}/d$ observed and theoretically derived for homogeneous bubble swarms ($u_{s}$ is the bubble slip velocity); (iii) the liquid turbulence is anisotropic with the ratio of turbulence intensities between the vertical and horizontal components in the range 1.9–2.1; (iv) the t.k.e. production by air bubbles is much larger than that by liquid mean shear; and (v) an increasing fraction of the available work done by bubbles is deposited into liquid turbulence as one moves away from the plume centreline. Together with the existing knowledge of homogeneous bubble swarms, our results of the heterogeneous bubble plume support the view that millimetre-sized bubbles create specific patterns of liquid fluctuations that are insensitive to flow conditions and can therefore be possibly modelled by a universal form.
Bromine as indicator of source of lacustrine sedimentary organic matter in paleolimnological studies
Authors: Ribeiro Guevara Sergio , Rizzo Andrea , Daga Romina , Williams Natalia , Villa Stefania
Published: March 2019

Bromine (Br) to organic matter (OM) concentration ratio is studied in lake sediment sequences to provide information on environmental changes modifying OM production. The sequences studied were extracted from shallow lakes Morenito, El Trébol, Escondido, and Portezuelo; and deep lakes Futalaufquen, Moreno, and Traful (North Patagonia Andean range). Lake Morenito, a former Lake Moreno bay until its closure in AD 1960, showed a decrease in Br:OM ratios from 1.38 to 0.74 after lake closure, associated with an increase of primary autochthonous productivity attributable to the development of submerged and emerging macrophytes. Sedimentary sequences from Lakes Escondido, Portezuelo, and El Trébol (with large participation of macrophytes in primary productivity), and from Lakes Moreno, Futalaufquen, and Traful (with little development of littoral macrophytes), showed Br:OM ratios consistent with the Lake Morenito pattern. Consistently, the morphometric parameters mean depth and shoreline development correlate with Br:OM ratios. Therefore, Br:OM ratios can be associated with the composition of primary autochthonous productivity, with values of about 0.7 associated to significant macrophyte contributions, and higher values associated with more pelagic contributions. Accordingly, Br:OM variations along a sedimentary sequence can be associated with modifications on the composition of the primary autochthonous productivity of the water body, providing information on environmental changes.
Mid- to late Holocene cooling events in the Korean Peninsula and their possible impact on ancient societies
Authors: Constantine Mark , Kim Minkoo , Park Jungjae
Published: March 2019

We present a multiproxy record using pollen, magnetic susceptibility, carbon isotopic composition, carbon/nitrogen ratio, and particle size of mid- to late Holocene environmental changes based on a sediment core from the Pomaeho lagoon on the east coast of Korea. The records indicate that climate deteriorations around 6400 cal yr BP and 4000 cal yr BP caused rapid vegetation changes in the study area, which were presumably attributable to low sunspot activity and strong El Niño–like conditions, respectively. These two cooling events were likely modulated by different climate mechanisms, as El Niño–Southern Oscillation activity began to strengthen around 5000 cal yr BP. These events may have had a substantial impact on ancient societies in the study area. Combining our results with archaeological findings indicated that climate deterioration led to drastic declines in local populations around 6400 cal yr BP, 4400 cal yr BP, and 4000 cal yr BP. Because of its high population, coastal East Asia (e.g., eastern China, Japan, and Korea) is particularly vulnerable to potential cooling events in the future. Therefore, there is a strong need for detailed paleoclimate information in this region.
Change in Atlantic cod migrations and adaptability of early land-based fishers to severe climate variation in the North Atlantic
Authors: Edvardsson Ragnar , Patterson William P. , Bárðarson Hlynur , Timsic Sandra , Ólafsdóttir Guðbjörg Ásta
Published: March 2019

We use biochemical, biological, archaeological, and historical analysis to examine relationships between Atlantic cod migration, sea temperature, and shifts in the distribution and occupancy of historical fishing sites in Iceland during the last millennium. Results support the hypothesis that the cooling climate of the North Atlantic during the period commonly referred to as the Little Ice Age coincided with changes in Atlantic cod migration patterns. Historical analysis shows a concomitant increase in reports of worsening Atlantic cod fishing and a severe decrease in domestic fishing, particularly in north Iceland. We conclude that Atlantic cod fisheries in Iceland originally thrived because of the proximity to cod migration routes. However, despite the mobility of local fishers, fluctuations in fish migrations, coupled with a harsher climate and increased competition for fishing grounds, resulted in a stagnation that lasted until the eventual modernization of the fishery in the mid-nineteenth century.
Euthanasia and assisted suicide of persons with psychiatric disorders: the challenge of personality disorders
Authors: Nicolini Marie E. , Peteet John R. , Donovan G. Kevin , Kim Scott Y. H.
Published: March 2019

Background

Euthanasia or assisted suicide (EAS) for psychiatric disorders, legal in some countries, remains controversial. Personality disorders are common in psychiatric EAS. They often cause a sense of irremediable suffering and engender complex patient–clinician interactions, both of which could complicate EAS evaluations.

Methods

We conducted a directed-content analysis of all psychiatric EAS cases involving personality and related disorders published by the Dutch regional euthanasia review committees (N = 74, from 2011 to October 2017).

Results

Most patients were women (76%, n = 52), often with long, complex clinical histories: 62% had physical comorbidities, 97% had at least one, and 70% had two or more psychiatric comorbidities. They often had a history of suicide attempts (47%), self-harming behavior (27%), and trauma (36%). In 46%, a previous EAS request had been refused. Past psychiatric treatments varied: e.g. hospitalization and psychotherapy were not tried in 27% and 28%, respectively. In 50%, the physician managing their EAS were new to them, a third (36%) did not have a treating psychiatrist at the time of EAS request, and most physicians performing EAS were non-psychiatrists (70%) relying on cross-sectional psychiatric evaluations focusing on EAS eligibility, not treatment. Physicians evaluating such patients appear to be especially emotionally affected compared with when personality disorders are not present.

Conclusions

The EAS evaluation of persons with personality disorders may be challenging and emotionally complex for their evaluators who are often non-psychiatrists. These factors could influence the interpretation of EAS requirements of irremediability, raising issues that merit further discussion and research.
Multi-DoFs Exoskeleton-Based Bilateral Teleoperation with the Time-Domain Passivity Approach
Authors: Buongiorno Domenico , Chiaradia Domenico , Marcheschi Simone , Solazzi Massimiliano , Frisoli Antonio
Published: March 2019

It is well known that the sense of presence in a tele-robot system for both home-based tele-rehabilitation and rescue operations is enhanced by haptic feedback. Beyond several advantages, in the presence of communication delay haptic feedback can lead to an unstable teleoperation system. During the last decades, several control techniques have been proposed to ensure a good trade-off between transparency and stability in bilateral teleoperation systems under time delays. These proposed control approaches have been extensively tested with teleoperation systems based on identical master and slave robots having few degrees of freedom (DoF). However, a small number of DoFs cannot ensure both an effective restoration of the multi-joint coordination in tele-rehabilitation and an adequate dexterity during manipulation tasks in rescue scenario. Thus, a deep understanding of the applicability of such control techniques on a real bilateral teleoperation setup is needed. In this work, we investigated the behavior of the time-domain passivity approach (TDPA) applied on an asymmetrical teleoperator system composed by a 5-DoFs impedance designed upper-limb exoskeleton and a 4-DoFs admittance designed anthropomorphic robot. The conceived teleoperation architecture is based on a velocity–force (measured) architecture with position drift compensation and has been tested with a representative set of tasks under communication delay (80 ms round-trip). The results have shown that the TDPA is suitable for a multi-DoFs asymmetrical setup composed by two isomorphic haptic interfaces characterized by different mechanical features. The stability of the teleoperator has been proved during several (1) high-force contacts against stiff wall that involve more Cartesian axes simultaneously, (2) continuous contacts with a stiff edge tests, (3) heavy-load handling tests while following a predefined path and (4) high-force contacts against stiff wall while handling a load. The found results demonstrated that the TDPA could be used in several teleoperation scenarios like home-based tele-rehabilitation and rescue operations.
Development of a mechanistic dengue simulation model for Guangzhou
Authors: Mincham G. , Baldock K. L. , Rozilawati H. , Williams C. R.
Published: March 2019

Dengue infection in China has increased dramatically in recent years. Guangdong province (main city Guangzhou) accounted for more than 94% of all dengue cases in the 2014 outbreak. Currently, there is no existing effective vaccine and most efforts of control are focused on the vector itself. This study aimed to evaluate different dengue management strategies in a region where this disease is emerging. This work was done by establishing a dengue simulation model for Guangzhou to enable the testing of control strategies aimed at vector control and vaccination. For that purpose, the computer-based dengue simulation model (DENSiM) together with the Container-Inhabiting Mosquito Simulation Model (CIMSiM) has been used to create a working dengue simulation model for the city of Guangzhou. In order to achieve the best model fit against historical surveillance data, virus introduction scenarios were run and then matched against the actual dengue surveillance data. The simulation model was able to predict retrospective outbreaks with a sensitivity of 0.18 and a specificity of 0.98. This new parameterisation can now be used to evaluate the potential impact of different control strategies on dengue transmission in Guangzhou. The knowledge generated from this research would provide useful information for authorities regarding the historic patterns of dengue outbreaks, as well as the effectiveness of different disease management strategies.
“I'm gonna Spanglish it on you”: Self-reported vs. oral production of Spanish–English codeswitching
Authors: Cox Jessica G. , LaBoda Ashley , Mendes Najee
Published: March 2019

Much bilingualism research includes some consideration of codeswitching, which may be measured via self-report, an experimental task, or sociolinguistic interview; however, there is little triangulation across measures in either psycholinguistic or sociolinguistic approaches. To consider possible differences between self-report and oral production of codeswitching, Spanish–English bilinguals completed a codeswitching questionnaire and oral production in an autobiographical memory task. They also completed proficiency and executive function tests. We found that broad measures of self-reported and orally produced codeswitches were positively correlated, although relationships with proficiency and executive function were more complex. These findings may direct future studies’ operationalization of codeswitching.
The Influence of Isoconcentration Surface Selection in Quantitative Outputs from Proximity Histograms
Authors: Barton Dallin J , Hornbuckle B Chad , Darling Kristopher A , Thompson Gregory B
Published: March 2019

Isoconcentration surfaces are commonly used to delineate phases in atom probe datasets. These surfaces then provide the spatial and compositional reference for proximity histograms, the number density of particles, and the volume fraction of particles within a multiphase system. This paper discusses the influence of the isoconcentration surface selection value on these quantitative outputs, using a simple oxide dispersive strengthened alloy, Fe91Ni8Zr1, as the case system. Zirconium reacted with intrinsic oxygen impurities in a consolidated ball-milled powder to precipitate nanoscale zirconia particles. The zirconia particles were identified by varying the Zr-isoconcentration values as well as by the maximum separation data mining method. The associated outputs mentioned above are elaborated upon in reference to the variation in this Zr isosurface value. Considering the dataset as a whole, a 10.5 at.% Zr isosurface provided a compositional inflection point for Zr between the particles and matrix on the proximity histogram; however, this value was unable to delineate all of the secondary oxide particles identified using the maximum separation method. Consequently, variations in the number density and volume fraction were observed as the Zr isovalue was changed to capture these particles resulting in a loss of the compositional accuracy. This highlighted the need for particle-by-particle analysis.
A printed multiband MIMO antenna with decoupling element
Authors: Xu Ziyu , Zhang Qisheng , Guo Linyan
Published: March 2019

A printed multiband Multi-Input Multiple-Output (MIMO) antenna is proposed in this paper. This MIMO antenna system comprises two symmetric printed monopole antennas. Each antenna element consists of multiple bend lines, producing four resonant modes and covering the GSM900, PCS, LTE2300, and 5G bands. Simulated and measured results prove that the proposed MIMO antenna can be applied to traditional 2G, 3G, 4G, and present 5G mobile communication. By etching four invertedL-shaped grooves on its ground plate, mutual coupling between the adjacent antenna elements has been suppressed. This makes the |S21| at all four resonant modes is lower than −40 dB. In addition, its low coupling mechanism has been analyzed by surface current distribution. The designed multiband MIMO antenna provides an idea of reference to realize low mutual coupling between antenna elements, which is also realizable in infrared or optical regimes with appropriate designs.
A flexible wide band single fed slot antenna with circular polarizing rotated elliptical ground and impulse response
Authors: Zahran Sherif R. , Abdalla Mahmoud A. , Gaafar Abdelhamid
Published: March 2019

In this paper, a flexible single fed planar circular polarized slot antenna is proposed for Internet of Things wideband applications. The antenna flexibility is achieved by employing a mechanically bendable liquid crystalline polymer substrate. The overall antenna volume is 50 mm × 42 mm × 0.1 mm. The antenna design uses 45° rotated elliptical ground structure for generating circular polarized radiation over wideband spectrum. Two parametrical analyses targeting the slot ground are introduced in order to achieve the most efficient design. The final antenna design demonstrates a good matching in terms of reflection coefficient (<−10 dB), semi-omnidirectional radiation patterns, average gain of 4 dB, and <3 dB axial ratio over entire frequency band of operation. All antenna parameters are studied in both straight and bent antenna setup scenarios. Good agreement between simulation and measurement results of the antenna parameters are achieved. For both straight and bent antenna scenarios, the antenna receiving functionality in time domain is confirmed by retrieving highly correlated impulse responses.
Surface Imaging Functions for Elastic Reverse Time Migration
Authors: Pollitz Fred F.
Published: March 2019

Reverse time migration is often used to interpret acoustic or three‐component seismic recordings by creating an image of subsurface seismic reflectors. Here I describe elastic reverse time migration imaging functions that are cast as waveform misfit sensitivity kernels of contrasts in material parameters across hypothetical seismic discontinuities, that is, specular reflectors. The proposed “surface” imaging functions are theoretically applicable to either reflected or converted waves in order to estimate the location and reflectivity of these discontinuities. The surface imaging functions, as well as volumetric sensitivity kernels that target point diffractors, are tested on sets of synthetic surface array recordings that sample the 3‐D seismic wavefield on simple 2‐D structures generated using a 2.5‐D spectral element method. These tests illustrate that in contrast with the volumetric sensitivity kernels, the reflectivity is generally dominated by a high‐amplitude peak that coincides with input locations of discontinuities. Passive recordings of microseismicity, shot gathers, or a combination thereof can be potentially interpreted with the new surface imaging functions to yield useful reflectivity images.
Response of the Diurnal Cycle of Summer Rainfall to Large‐Scale Circulation and Coastal Upwelling at Hainan, South China
Authors: Shi Rui , Cai Qinbo , Dong Lingyu , Guo Xinyu , Wang Dongxiao
Published: March 2019

The modulation of coastal rainfall at Hainan by large‐scale circulation and coastal upwelling is studied using observations and numerical modeling. Tropical Rainfall Measuring Mission data show that the monthly mean rainfall off southern Hainan was considerably higher in August 2010 than in August 2011. The main cause of this difference is an intensification of offshore rainfall from midnight to early morning. Compared with the multiyear (2000–2017) average field, reanalysis data show that there is an apparent increase in atmospheric humidity in August 2010. During this time, a moderate El Niño was decaying and a new La Niña event was developing, so a significant adjustment of the large‐scale circulation was observed in the western Pacific. The resulting anomalous onshore wind depresses the development of upwelling, leading to a relatively warm sea surface temperature off the south coast of Hainan, which in turn enhances the land‐sea thermal contrast and land breeze at night. Decreases in upwelling intensity and asymmetric intensification of nocturnal and daytime offshore rainfall are confirmed not only in the summer of 2010 but also in the summer of 2003. Numerical simulations using the Weather Research and Forecasting model verify that the enhanced land breeze ultimately leads to pronounced coastal rainfall off southern Hainan at night. The results indicate that localized surface convergence associated with the sea and land breezes may be more important than the atmospheric humidity and convective instability in modulating the diurnal cycle of rainfall for tropical islands.