bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultra-broadband nanophotonic phase shifter based on subwavelength metamaterial waveguides
Authors: González-Andrade David , Luque-González José Manuel , Gonzalo Wangüemert-Pérez J. , Ortega-Moñux Alejandro , Cheben Pavel , Molina-Fernández Íñigo , Velasco Aitor V. 
Published: December 2019

Optical phase shifters are extensively used in integrated optics not only for telecom and datacom applications but also for sensors and quantum computing. While various active solutions have been demonstrated, progress in passive phase shifters is still lacking. Here we present a new type of ultra-broadband 90° phase shifter, which exploits the anisotropy and dispersion engineering in subwavelength metamaterial waveguides. Our Floquet–Bloch calculations predict a phase-shift error below

±
1.7
°

over an unprecedented operation range from 1.35 to 1.75 μm, i.e., 400 nm bandwidth covering the E, S, C, L, and U telecommunication bands. The flat spectral response of our phase shifter is maintained even in the presence of fabrication errors up to

±
20

nm

, showing greater robustness than conventional structures. Our device was experimentally demonstrated using standard 220 nm thick SOI wafers, showing a fourfold reduction in the phase variation compared to conventional phase shifters within the 145 nm wavelength range of our measurement setup. The proposed subwavelength engineered phase shifter paves the way for novel photonic integrated circuits with an ultra-broadband performance.
ICTs as Juju: African inspiration for understanding the compositeness of being human through digital technologies
Authors: Nyamnjoh Francis B. 
Published: December 2019

Abstract
In this article, I liken information and communication technologies (ICTs) or digital technologies to what we in West and Central Africa have the habit of referring to as Juju. I invite as scholars of the digital humanities to see in the region’s belief in incompleteness and the compositeness of being human, as well as in the capacity to be present everywhere at the same time an indication that we have much to learn from the past on how best to understand and harness current purportedly innovative advances in ICTs. The idea of digital technologies making it possible for humans and things to be present even in their absence and absent even in their presence is not that dissimilar to the belief in what is often labelled and dismissed as witchcraft and magic that lends itself to a world of infinite possibilities – a world of presence in simultaneous multiplicities and eternal powers to redefine reality. The article argues in favour of incompleteness as a normal way of being. It challenges students of humanity to envisage a relationship between humans and digital technologies that is founded less on dichotomies and binary oppositions, nor on zero-sum games of conquest and superiority. If humans are present in things and things in humans, thanks to the interconnections, the flexibility and fluidity of being that come with recognition of and provision for incompleteness, it is important to see things and humans not only as intricately entangled, but also as open-ended composites.
A comparative analysis of social media messaging by African-centred LGBT refugee NGOs
Authors: Kenix Linda Jean , Abikanlu Femi 
Published: December 2019

Abstract
Approximately 40 per cent of countries categorize homosexuality as illegal. However, refugee status is still granted largely on the basis of the 1951 Convention Relating to the Status of Refugees, which found that a refugee is a person who has a ‘well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion’. On that basis, few countries allow sexual orientation as grounds for refugee status. Owing to the extraordinary odds of gaining successful refugee status and because lesbian, gay, bisexual and transgender (LGBT) asylum seekers are often socially isolated in their search for refugee status, there is a heightened need for non-government organization support networks for these individuals. This research explores social media from four LGBT refugee organizations, largely focused on Africa, to ascertain where the differences and similarities reside in communicating with community members, sharing information, building community and encouraging action.
Case report of a ruptured uterine sacculation in the 19th week of pregnancy
Authors: Scharf Jann Lennard , Gitas Georgios , Hartge David , Rody Achim , Kotanidis Christos 
Published: December 2019

Abstract

Background
Uterine sacculation with a resulting uterine rupture is a rare complication in pregnant patients. Fibroids or a previous cesarean section increase the risk of severe complications such as a uterine rupture due to increased pressure and the elongation of the affected uterine segment. Prenatal clinical diagnosis and medical imaging of a uterine sacculation and rupture of the uterus remain challenging, even with the most modern imaging techniques. An early diagnosis is essential to reduce severe complications.

Case presentation
Here, we report the case of a 38-year-old female patient II G I P in the 19th week of pregnancy with a ruptured uterine sacculation.

Conclusion
This case report is intended to raise awareness for the importance of the knowledge and supervision of a retroverted uterus in early pregnancy, especially after a cesarean section.
New results on the q-generalized Bernoulli polynomials of level m
Authors: Urieles Alejandro , Ortega María José , Ramírez William , Vega Samuel 
Published: December 2019

Abstract
This paper aims to show new algebraic properties from the q-generalized Bernoulli polynomials

B

n

[
m
-
1
]

(
x
;
q
)

B_n^{[m - 1]}(x;q)

of level m, as well as some others identities which connect this polynomial class with the q-generalized Bernoulli polynomials of level m, as well as the q-gamma function, and the q-Stirling numbers of the second kind and the q-Bernstein polynomials.
Orthogonal stability of the generalized quadratic functional equations in the sense of Rätz
Authors: Aiemsomboon Laddawan , Sintunavarat Wutiphol 
Published: December 2019

Abstract
Let (X, ⊥) be an orthogonality module in the sense of Rätz over a unital Banach algebra A and Y be a real Banach module over A. In this paper, we apply the alternative fixed point theorem for proving the Hyers-Ulam stability of the orthogonally generalized k-quadratic functional equation of the form

a
f
(
k
x
+
y
)
+
a
f
(
k
x
-
y
)
=
f
(
a
x
+
a
y
)
+
f
(
a
x
-
a
y
)
+

(

2

k

2

-
2

)

f
(
a
x
)

af(kx + y) + af(kx - y) = f(ax + ay) + f(ax - ay) + \left( {2{k^2} - 2} \right)f(ax)

for some |k| > 1, for all a ɛ A
1 := {u ɛ A||u|| = 1} and for all x, y ɛ X with x⊥y, where f maps from X to Y.
Design Thinking for German Vocational Schools? Discovering of an Innovative Approach by Testing in Teacher Education
Authors: Krüger Marc 
Published: December 2019

Abstract
Design Thinking is an innovative approach that solves concrete problems and develops new products. Its constant spreading in industry, business, and non-profit organizations raises the question to which extent this approach may be of importance for German vocational schools. There is an increasing debate among scientists about design thinking in educational contexts, in which different authors regard it as useful for curriculum and school development as well as for coping with everyday school life. To assess the importance of design thinking for German vocational schools, pre-service teachers have tackled vocational school issues with design thinking. The paper concludes that design thinking is indeed of interest to vocational schools and that further work is recommended.
Suspected reactivation of extrapulmonary tuberculosis focus after non-medical abuse of anabolic androgenic steroids: a case report
Authors: Singh Vikramjit , Batta Angelika 
Published: December 2019

Abstract

Background
Youth population has a common tendency to use androgenic steroids. The reasons for such abuse vary from performance enhancement to muscle building in order to enhance physical appearance. Such rampant abuse, aided by fitness centers and gym trainers, has a huge risk of side effects such as hepatic dysfunctions and increased risk of infections.

Case presentation
We report a case of 21-year-old man who started with anabolic steroids, namely testosterone enanthate, nandrolone decanoate and boldenone undecylenate injections, for the purpose of muscle building and strength training at his fitness center. He presented to his family physician after 2 months with upper neck swelling on right side 5 × 4 cm for 15–20 days. He was started on Augmentin 625 mg tablet three times a day for 7 days. On seventh day, swelling persisted, and fine needle aspiration cytology (FNAC) was performed, which was suggestive of granulomatous lesion likely to be tuberculosis. The patient was started with anti-tubercular therapy (ATT) under category A, but swelling did not improve and repeated FNAC was advised. The ATT was withheld and Augmentin tablet was restarted for another 3 days. A revised diagnosis of acute suppurative lymphadenitis was made, and an incision and drainage of the abscess was performed. The patient was started on Amikacin 500 intramuscular injection for 5 days along with faropenem and cefuroxime axetil tablets for 14 days. He initially started recovering but returned with pustular discharge from the incision mark. It was decided to reinitiate the ATT-intensive phase medication for another 2 months. The patient finally recovered with complete healing of the wound. The frequent change of treating physician and misuse of antimicrobials made the diagnosis tougher, contributing to delay in the optimum therapy.

Conclusion
This case highlights the abuse of multiple steroids together in the form of stacking by a young adult, which leads to a rare serious adverse effect such as suspected tubercular reactivation.
Power Average Operators of Trapezoidal Cubic Fuzzy Numbers and Application to Multi-attribute Group Decision Making
Authors: Fahmi Aliya , Amin Fazli , Abdullah Saleem , Shakeel Muhammad 
Published: December 2019

Abstract
Trapezoidal cubic fuzzy numbers (TzCFNs) are an extraordinary cubic fuzzy set on a real number set. TzCFNs are useful for dealing with well-known quantities in decision data and decision making problems themselves. This paper is about multi-attribute group decision making problems in which the attribute values are stated with TzCFNs, which are solved by developing a new decision method based on power average operators of TzCFNs. The new operation laws for TzCFNs are given. Hereby, the power average operator of real numbers is extended to four kinds of power average operators of TzCFNs, involving the power average operator of TzCFNs, the weighted power average operator of TzCFNs, the power ordered weighted average operator of TzCFNs, and the power hybrid average operator of TzCFNs. In the proposed group decision method, the individual overall evaluation values of alternatives are generated by using the power average operator of TzCFNs. Applying the hybrid average operator of TzCFNs, the specific general evaluation standards of alternatives are then combined into the collective ones, which are used to rank the alternatives. The example analysis shows the practicality and effectiveness of the proposed method.
Clay-Based Brick Porosity Estimation Using Image Processing Techniques
Authors: Jida Safa , Ouallal Hassan , Aksasse Brahim , Ouanan Mohammed , Amraoui Mohamed El , Azrour Mohamed 
Published: December 2019

Abstract
This work intends to apprehend and emphasize the contribution of image-processing techniques and computer vision in the treatment of clay-based material known in Meknes region. One of the various characteristics used to describe clay in a qualitative manner is porosity, as it is considered one of the properties that with “kill or cure” effectiveness. For this purpose, we use scanning electron microscopy images, as they are considered the most powerful tool for characterising the quality of the microscopic pore structure of porous materials. We present various existing methods of segmentation, as we are interested only in pore regions. The results show good matching between physical estimation and Voronoi diagram-based porosity estimation.
On quality of NKG2015 geoid model over the Nordic countries
Authors: Eshagh Mehdi , Berntsson Jenny 
Published: December 2019

Abstract
The NKG2015 geoid model covers the Nordic and Baltic countries and has been computed based on the least-squares modification of Stokes’ formula with additive corrections method. New and precise terrestrial, airborne and shipborne gravimetric measurements, the recent global gravity model of the gravity field and steady-state ocean circulation explorer (GOCE) and detailed digital terrain models over each territory have been used for computing this new geoid model. Some estimates for the error of this model have been roughly presented by comparing it with the global navigation satellite system (GNSS) data over each country. In this paper, our goal is to have a closer look at the relative error of this model by performing some statistical tests and finding the proper corrective surface for absorbing the systematic errors over each country. Our main assumption is realisticity of the errors of GNSS/levelling data and we will investigate its consequences in estimating the error of the geoid model. Our results show that the 4-parameter corrective surface is suitable for modelling the systematic trends of the differences between the gravimetric and GNSS geoid heights in Sweden, Denmark and Finland, but a filtered discrepancies by a confidence interval of 95% should be used for Sweden. A 7-aparameter model is suitable for the filtered discrepancies with the confidence interval of 95% in Norway. Based on the selected corrective surface and our newly developed regional iterative variance estimator, the confidence interval for the error of NKG2015 geoid model in Sweden, Denmark and Norway yielded 0-6.5 mm, 1.8-5.2 mm, 14.8-17.7 mm, respectively with a confidence level of 95%. We could not estimate the geoid error in Finland because the given error of the GNSS/levelling heights is significantly larger than the size of residuals. Based on the selected corrective surfaces and our presented local variance estimator, the average error of geoid becomes 3.6, 2.4, 8.8 and 5.8 mm with a confidence interval of 68%, respectively, over Sweden, Denmark, Norway and Finland.
Dual-wavelength fluorescent anti-counterfeiting fibers with skin-core structure
Authors: Zhang Huihui , Xu Yuanyuan , Yang Gesheng , Zhang Yaopeng , Shao Huili , Li Yonggui 
Published: December 2019

AbstractIn this work, a skin-core structure was designed, and three kinds of dual-wavelength fluorescent anti-counterfeiting (DWFA) fibers, including UV short-wavelength/UV long-wavelength, infrared/UV short-wavelength, and infrared/UV long-wavelength excitable DWFA fibers with skin-core structure, were spun using fluorescent powder/PP pellets as the skin material and pure PP as the core material. The results showed that these DWFA fibers emitted two different colors of light under excitation of two different wavelength lights, which exhibited higher anti-counterfeiting safety. Take UV short-wavelength/UV long-wavelength DWFA fibers, for example; the influence of skin-core ratio on the structure and properties of fibers were investigated, and then the luminous efficiency of DWFA fibers with skin-core structure and homogenous structure was compared. The microscope photos and 3D simulation of fluorescent powder in fibers by confocal laser scanning microscope showed that the fluorescent powders were basically distributed in the skin layer of fibers. The crystallinity degree and tensile strength of DWFA fibers with skin-core structure decreased first and then increased with the decrease in skin-core ratio, whereas elongation of fibers showed an increasing trend. Compared with homogenous DWFA fibers, the skin-core DWFA fibers exhibited higher luminous efficiency under the same fluorescent powder content.
Natural radioactivity, radon emanating power and mass exhalation rate of environmental soil samples from Karabük province, Turkey
Authors: Kurnaz Aslı , Turhan Şeref , Hançerlioğulları Aybaba , Gören Elif , Karataşlı Muhammet , Altıkulaç Aydan , Erer Ahmet M. , Metin Onur 
Published: December 2019

Abstract
In this study, content of natural radionuclides (226Ra, 232Th and 40K) and radon emanating power and radon mass exhalation rate of surface soil samples collected around industrial province Karabük in which the first iron steel plant was built in 1937 were determined by high-resolution γ-ray spectrometry with a high purity germanium detector. The average activity concentration of 226Ra, 232Th and 40K in soil samples were measured as 30 ± 2, 28 ± 2 and 251 ± 20 Bq kg−1, respectively. The average value of radon emanating power and mass exhalation rate of soil samples were found as 31 % and 19 μBq kg−l s−l, respectively. Assessment of possible radiation hazards to the people due to external exposure was done by estimating the outdoor absorbed gamma dose rate in the air at 1 m above the soil, the corresponding annual effective dose, and the excess lifetime cancer risk. The average outdoor gamma dose rate, annual effective dose, and lifetime cancer risk were estimated as 41 nGy h−1, 51 μSv y−1 and 2.0 × 10−4, respectively. A comparison of the activity and radiological results obtained for the studied samples with the corresponding worldwide average values indicates that the results are below the world average values.
Design and optimization of solar steam generation system for water purification and energy utilization: A review
Authors: Xu You , Yin Jiacheng , Wang Jun , Wang Xianbao 
Published: December 2019

AbstractSolar steam generation with low-cost and excellent energy efficiency is of great significance for alleviating an energy crisis, reducing water pollution and promoting seawater desalination. However, there are still numerous challenges for solar steam generation system to practical energy utilization. In this review, based on our previous research, we summarize various methods of solar steam generation, photothermal conversion mechanism and efficiency. We studied a series of effecting factors for solar steam generation. Our systematic investigation provided a clearer understanding of how to design and optimize the photothermal conversion system to improve the steam generation rate and energy conversion rate, including improving light absorption, reducing heat loss, and optimizing water supply. This article aims to make a comprehensive review of present solar steam technology, so that people can better apply photothermal conversion technology. Meanwhile, it also provides a route for the selection of photothermal materials, the design and optimization of the photothermal conversion system.
Tribological investigation of multilayer CrN/CrCN/TaN films deposited by close field unbalanced magnettron sputtering
Authors: Bahce Erkan , Cakir Nese 
Published: December 2019

AbstractCrN/CrCN/TaN multilayer films were deposited onto the CoCrMo alloy substrates at different number layers as two, four and 8 layers by close-field unbalanced magnetron sputtering method. Microstructure and the tribo-logical properties of the films were characterized by XRD, SEM, pin-on-disk wear test, scratch test, micro hardness. CrN/CrCN/TaN multilayer coatings exhibited good adhesion properties on the CoCrMo alloy substrate. A very high hardness value of 60 GPa was obtained for 8 multilayered coating. As a result of the pin-on-disc wear tests, it was found that the tribological properties of the CoCrMo alloy were enhanced by coating its surface with this architecture by using close-field unbalanced magnetron system with used parameters.
Inertias of Laplacian matrices of weighted signed graphs
Authors: Monfared K. Hassani , MacGillivray G. , Olesky D. D. , van den Driessche P. 
Published: December 2019

Abstract
We study the sets of inertias achieved by Laplacian matrices of weighted signed graphs. First we characterize signed graphs with a unique Laplacian inertia. Then we show that there is a sufficiently small perturbation of the nonzero weights on the edges of any connected weighted signed graph so that all eigenvalues of its Laplacian matrix are simple. Next, we give upper bounds on the number of possible Laplacian inertias for signed graphs with a fixed flexibility τ (a combinatorial parameter of signed graphs), and show that these bounds are sharp for an infinite family of signed graphs. Finally, we provide upper bounds for the number of possible Laplacian inertias of signed graphs in terms of the number of vertices.
On a notion of entropy in coarse geometry
Authors: Zava Nicolò 
Published: December 2019

AbstractThe notion of entropy appears in many branches of mathematics. In each setting (e.g., probability spaces, sets, topological spaces) entropy is a non-negative real-valued function measuring the randomness and disorder that a self-morphism creates. In this paper we propose a notion of entropy, called coarse entropy, in coarse geometry, which is the study of large-scale properties of spaces. Coarse entropy is defined on every bornologous self-map of a locally finite quasi-coarse space (a recent generalisation of the notion of coarse space, introduced by Roe). In this paper we describe this new concept, providing basic properties, examples and comparisons with other entropies, in particular with the algebraic entropy of endomorphisms of monoids.
A Modified Chemical Index to Predict Fly Ash Dosage for Mitigating Alkali-Silica Reaction
Authors: Deschenes Richard , Jones Casey , Giannini Eric R. , Hale Micah 
Published: December 2019

Abstract
It is well chronicled that coal fly ash can mitigate the risk of alkali-silica reaction (ASR) in concrete structures. However, the efficacy of individual fly ashes is highly dependent on their chemical composition. Prescriptive requirements for ASR mitigation have largely focused on whether the fly ash is classified as Class F or Class C per ASTM C618, Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete, whereas performance requirements may require extensive testing to satisfactorily demonstrate mitigation potential of a fly ash. Previous research established the need for an accurate model to predict required fly ash replacement rates for ASR mitigation based on the chemical constituents of cement and fly ash. Therefore, a new model is proposed to account for the availability of each chemical constituent from cement and fly ash separately, utilizing ASTM C1260, Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar Method), and ASTM C1567, Standard Test Method for Determining the Potential Alkali-Silica Reactivity of Combinations of Cementitious Materials and Aggregate (Accelerated Mortar Bar Method), test data. The successful development of models based on 14-day and 28-day expansion data from these tests is presented in this article.