bluuebunny/crossref_metadata_2025 huggingface dataset:
Signature-causality reflection generated by Abelian gauge transformations
Authors: Garat Alcides
Published: March 2020

In this paper, we want to better understand the causality reflection that arises under a subset of Abelian local gauge transformations in geometrodynamics. We proved in previous papers that in Einstein–Maxwell spacetimes, there exist two local orthogonal planes of gauge symmetry at every spacetime point for non-null electromagnetic fields. Every vector in these planes is an eigenvector of the Einstein–Maxwell stress–energy tensor. The vectors that span these local orthogonal planes are dependent on electromagnetic gauge. The local group of Abelian electromagnetic gauge transformations has been proved isomorphic to the local groups of tetrad transformations in these planes. We called LB1 the local group of tetrad transformations made up of SO(1, 1) plus two different kinds of discrete transformations. One of the discrete transformations is the full inversion two by two which is a Lorentz transformation. The other discrete transformation is given by a matrix with zeroes on the diagonal and ones off-diagonal two by two, a reflection. The group LB1 is realized on this plane, we call this plane one, and is spanned by the time-like and one space-like vectors. The other local orthogonal plane is plane two and the local group of tetrad transformations, we call this LB2, which is just SO(2). The local group of Abelian electromagnetic gauge transformations is isomorphic to both LB1 and LB2, independently. It has already been proved that a subset of local electromagnetic gauge transformations that leave the electromagnetic tensor invariant induces a change in sign in the norm of the tetrad vectors that span the local plane one. The reason is that one of the discrete transformations on the local plane one that belongs to the group LB1 is not a Lorentz transformation, it is a flip or reflection. It is precisely on this kind of discrete transformation that we have an interest since it has the effect of changing the signature and the causality. This effect has never been noticed before.
Electromagnetic effects on the stability of anisotropic cylinder
Authors: Sharif M. , Ama-Tul-Mughani Qanitah
Published: March 2020

This paper is devoted to analyzing the stability of charged anisotropic cylinder using the radial perturbation scheme. For this purpose, we consider the non-static cylindrically symmetric self-gravitating system and apply both Eulerian as well as Lagrangian approaches to establish a linearized perturbed form of dynamical equations. The conservation of baryon number is used to evaluate perturbed radial pressure in terms of an adiabatic index. A variational principle is developed to find a characteristic frequency which helps to examine the combined effect of charge and anisotropy on the stability of gaseous star. It is found that dynamical instability can be prevented until the radius of cylinder exceeds the limit [Formula: see text] and anisotropy increases the instability up to the limiting value of [Formula: see text]. Finally, we conclude that the system becomes more stable by increasing the definite amount of charge gradually.
Plasmonic refractive index sensor with multi-channel Fano resonances based on MIM waveguides
Authors: Fang Yihong , Wen Kunhua , Li Zhengfeng , Wu Bingye , Guo Zicong
Published: March 2020

A multi-channel Fano resonant structure is proposed and analyzed based on subwavelength metal–insulator–metal (MIM) waveguides. First, two MIM output ports associated with specific side-coupled cavities are designed to locate at the center and quarter positions of an end-coupled cavity, respectively. Since the interference between the dark and bright modes, dual-channel Fano resonances with asymmetrical lines shapes are obtained at both ports, respectively. High sensitivity and figure of merits are investigated. Besides, phase shifts are also investigated leading to positive and negative group delays available at the Fano peaks and dips, respectively. Likewise, two extra output ports with identical resonant cavities are placed on the other side of the end-coupled cavity. In this case, four-channel Fano resonances with considerable performances are obtained. The proposed structure is analyzed by the coupled mode theory and the finite difference time domain method. It is believed this device can be used as a chip-scale refractive index sensor and optical filter.
The Phenomenon of Bistable Phase Difference Intervals in the Times-Frequency Vibration Synchronization System Driven by Two Homodromy Exciters
Authors: Li Lingxuan , Chen Xiaozhe
Published: March 2020

A vibration system with two homodromy exciters operated in different rotational speed is established to investigate whether the phenomenon of bistable phase difference intervals exists in the times-frequency vibration synchronization system. Some constructive conclusions are proposed. (1) By introducing an average angular velocity perturbation parameter ε0 and two sets of phase difference perturbation parameters and ε2, the frequency capture criterion and the necessary criteria for realizing the times-frequency vibration synchronization are derived. The corresponding stability analysis is carried out. (2) By the theoretical analysis and experiments, it is verified that the times-frequency vibration synchronization system exists the phenomena of bistable phase difference interval. That is, the phase differences between the two homodromy exciters are stable around 180 degrees when they are located at a short distance; the antiphase synchronization phenomenon appears. On the contrary, they are stable around 0 degrees at the in-phase synchronization state. (3) Because of the two homodromy exciters operating in the different rotational speed, the vibration system obtains relatively complex compound motion trajectories; the corresponding application is investigated by adding a feeding material chamber. The times-frequency vibration synchronization system can be used to design the vibration mill for reducing its low-energy zone and developing chaotic mixing equipment for obtaining a better mixing effect.
Algorithms for Solving Nonhomogeneous Generalized Sylvester Matrix Equations
Authors: El-Sayed Ehab A. , El Behady Eid E.
Published: March 2020

This paper considers a new method to solve the first-order and second-order nonhomogeneous generalized Sylvester matrix equations AV+BW= EVF+R and MVF2+DV F+KV=BW+R, respectively, where A,E,M,D,K,B, and F are the arbitrary real known matrices and V and W are the matrices to be determined. An explicit solution for these equations is proposed, based on the orthogonal reduction of the matrix F to an upper Hessenberg form H. The technique is very simple and does not require the eigenvalues of matrix F to be known. The proposed method is illustrated by numerical examples.
Stanniocalcin-1 Alleviates Contrast-Induced Acute Kidney Injury by Regulating Mitochondrial Quality Control via the Nrf2 Pathway
Authors: Zhao Fei , Feng Li-Xin , Liu Qian , Wang Hong-Shen , Tang Cheng-Yuan , Cheng Wei , Deng Yin-Hao , Wu Xi , Yan Ping , Duan Xiang-Jie , Peng Jin-Cheng , Duan Shao-Bin
Published: March 2020

Contrast-induced acute kidney injury (CI-AKI) is the third common cause of acute kidney injury (AKI), which is associated with poor short- and long-term outcomes. Currently, effective therapy strategy for CI-AKI remains lacking. Stanniocalcin-1 (STC1) is a conserved glycoprotein with antiapoptosis and anti-inflammatory functions, but the role of STC1 in controlling CI-AKI is unknown. Here, we demonstrated a protective role of STC1 in contrast-induced injury in cultured renal tubular epithelial cells and CI-AKI rat models. Recombinant human STC1 (rhSTC1) regulated mitochondrial quality control, thus suppressing contrast-induced mitochondrial damage, oxidative stress, inflammatory response, and apoptotic injury. Mechanistically, activation of the Nrf2 signaling pathway contributes critically to the renoprotective effect of STC1. Together, this study demonstrates a novel role of STC1 in preventing CI-AKI and reveals Nrf2 as a molecular target of STC1. Therefore, this study provides a promising preventive target for the treatment of CI-AKI.
Analysis and Application of Transition Systems Based on Petri Nets and Relation Matrices to Business Process Management
Authors: Han Dong , Tian Yinhua
Published: March 2020

In order to improve the efficiency of conformance checking in business process management, a business alignment approach is presented based on transition systems between relation matrices and Petri nets. Firstly, a log-based relation matrix of the events is obtained according to the event log. Then, the events in the relation matrix are observed and the transitions in the model are firing, and the activities in the log and in the model are compared. Next, the states of the log and the model are recorded until no new state can be generated, so a transition system can be obtained which includes optimal alignments between the event log and the process model. Finally, two detailed algorithms are presented to obtain an optimal alignment and all optimal alignments between the trace and the model based on the given cost function, respectively. The availability and effectiveness of the proposed approach are proved theoretically.
PC Cable‐Stayed Bridge Main Girder Shear Lag Effects: Assessment of Single Cable Plane in Construction Stage
Authors: Li Yan-feng , Sun Xing-long , Bao Long-sheng
Published: March 2020

A model test and finite element analysis were conducted in this study to determine the distribution law of shear lag effect in the main beam section, a box girder, during the cable‐stayed bridge construction process. The experimental and theoretical results were compared in an example of loading the control section. The stress value of the cable tension area of the main beam upper edge was found to markedly change when tensiling the cable force and was accompanied by prominent shear lag effect. After a hanging basket load was applied, the main beam of certain sections showed alternating positive and negative shear lag characteristics. The shear lag distribution law in the box girder of the single‐cable‐plane prestressed concrete cable‐stayed bridge along the longitudinal direction was determined in order to observe the stress distribution of the girder. The results show that finite element analysis of the plane bar system should be conducted at different positions in the bridge under construction; the calculated shear lag coefficient of the cable force acting at the cable end of the cantilever reflects the actual force. In the beam segments between the cable forces, the shear lag coefficient determined by the ratio of the bending moment to the axial force reflects the actual stress at the cable force action point. In the midspan beam section between the action points of cable forces, the shear lag coefficient of the bending moment reflects the actual stress. The section shear lag coefficient can be obtained by linear interpolation of the beam section between the cable action point and the middle of the span.
Severe Hyponatremia-Induced Stress Cardiomyopathy: A Case Report and Review of Literature
Authors: Perera Irushna , Rajapakse Sanjeewa , De Silva Shamila T.
Published: March 2020

Takotsubo or stress cardiomyopathy is a non ischemic disease affecting the myocardium, which presents with typical features of myocardial ischemia. Although the presentation with acute central chest pain and shortness of breath mimics acute myocardial ischemia, there is an absence of actual disruption of cardiac blood supply via the coronaries due to acute plaque rupture or vascular spasm. The underlying pathophysiology of this clinical entity remains largely unclear, but a definite association with physical or emotional stress has been well established, hence the term “stress cardiomyopathy.” The list of potential triggers continues to grow as the disorder is increasingly detected by clinicians and cardiologists, with better clinical insight and improved availability of cardiac investigations. We report a patient with Takotsubo cardiomyopathy associated with severe hyponatremia.
Event-Related Potentials Elicited by Face and Face Pareidolia in Parkinson’s Disease
Authors: Akdeniz Gulsum , Vural Gonul , Gumusyayla Sadiye , Bektas Hesna , Deniz Orhan
Published: March 2020

Background. Parkinson’s disease is associated with impaired ability to recognize emotional facial expressions. In addition to a visual processing disorder, a visual recognition disorder may be involved in these patients. Pareidolia is a type of complex visual illusion that permits the interpretation of a vague stimulus as something known to the observer. Parkinson’s patients experience pareidolic illusions. N170 and N250 waveforms are two event-related potentials (ERPs) involved in emotional facial expression recognition. Objective. In this study, we investigated how Parkinson’s patients process face and face-pareidolia stimuli at the neural level using N170, vertex positive potential (VPP), and N250 components of event-related potentials. Methods. To examine the response of face and face-pareidolia processing in Parkinson’s patients, we measured the N170, VPP, and N250 components of the event-related brain potentials in a group of 21 participants with Parkinson’s disease and 26 control participants. Results. We found that the latencies of N170 and VPP responses to both face and face-pareidolia stimuli were increased along with their amplitudes, and the amplitude of N250 responses decreased in Parkinson’s patients compared to the control group. In both control and Parkinson’s patients, face stimuli generated greater ERP amplitude and shorter latency in responses than did face-pareidolia stimuli. Conclusion. The results of our study showed that ERPs associated with face and also face-pareidolia stimuli processing are changed in early-stage neurophysiological activity in the temporoparietal cortex of Parkinson’s patients.
Composite Anatomical Variations between the Sciatic Nerve and the Piriformis Muscle: A Nepalese Cadaveric Study
Authors: Jha Ameet Kumar , Baral Prakash
Published: March 2020

Piriformis syndrome is a rare syndrome which is one of the main causes of nondiscogenic sciatica causing severe low back pain due to entrapment of sciatic nerve either by the hypertrophy or by inflammation of the piriformis muscle. We have carried out dissection in 20 Nepalese cadavers. Out of 40 dissected gluteal regions, 37 exhibited typical appearance of sciatic nerve, piriformis muscle, and their relations resembling type-a, whereas 3 gluteal regions showed composite structural variations resembling type-b and type-c based on Beaton and Anson’s classification. Knowledge pertaining to such variations will be helpful during a surgical intervention in the gluteal region and in turn reduces the risk of injuring these nerves which are more susceptible to damage. Our study reports such variations in Nepalese population which will be helpful during evaluation of the pain induction in various test positions and also useful for analysis of the range of the neurological deficiency in sciatic nerve neuropathies. The present study also explains the basis of the unsuccessful attempt of the sciatic nerve block during popliteal block anaesthesia.
La pandemia que no vimos venir
Authors: León Gabriel
Published: March 2020

El año 2007, tres grupos de investigadores –incluyendo a académicos del Departamento de Geofísica de la Universidad de Chile– hicieron un interesante estudio sobre una zona de silencio sísmico que se extendía entre Constitución y Concepción (Ruegg et al., 2009).
Investigating the Function of Mutual Grooming in Captive Bonobos (Pan paniscus) and Chimpanzees (Pan troglodytes)
Authors: Allanic Morgane , Hayashi Misato , Matsuzawa Tetsuro
Published: March 2020

Social grooming is often exchanged between individuals in many primate species. Rates of bidirectional (or simultaneous mutual) grooming vary across primate species, and its function is not yet fully understood. For example, mutual grooming is frequent in chimpanzees but rare in most primate species including wild bonobos. There are, however, no quantitative data available in captive bonobos. Therefore, through the direct comparison between captive bonobos and chimpanzees, this study aimed to (i) compare the frequency of mutual grooming between Pan species, (ii) explore and compare the function of mutual grooming, and (iii) discuss the rarity of this behavior in wild bonobo populations. We tested three hypotheses following the previous literature in wild chimpanzees. The social bonding hypothesis states that mutual grooming facilitates the maintenance of strong dyadic bonds. The immediate investment hypothesis states that it serves to signal willingness to invest in the interaction. The switching hypothesis states that mutual grooming serves no function but only occurs as an overlap to change the direction of unidirectional grooming. Our findings strongly supported the immediate investment hypothesis, but not the others. Grooming bouts that included mutual grooming were longer and more equitable than bouts without, illustrating that captive Pan species use mutual grooming to maximize their short-term benefits and increase the social value of their interaction. Captive bonobos performed mutual grooming in similar proportions and for similar functions as captive and wild chimpanzees do. This contrasts with wild bonobos who engage in this behavior only rarely. We suggest that the differences in patterns of mutual grooming between captive and wild bonobos might be explained by different degrees of kinship or by a potential intraspecies variation.
Uso de Facebook y persuasión interpersonal masiva
Authors: Oliva Edna Idalia Paulina Navarro , Castillo María Magdalena Alonso , Facundo Francisco Rafael Guzmán , Bermúdes Javier Álvarez , Puente Linda Azucena Rodríguez
Published: March 2020

Objetivo: analizar la influencia de la persuasión interpersonal masiva a través del uso de Facebook en el consumo de alcohol en jóvenes universitarios. Método: diseño predictivo y transversal, se realizó un muestreo fue probabilístico y estratificado para una muestra de 730 jóvenes universitarios. Se utilizó una Cédula de Datos Personales y Prevalencias de Consumo de Alcohol, Cuestionario de Uso de Facebook, la Prueba de Identificación de Desordenes por Uso de Alcohol, el Listado de Pensamientos y un Libro de Códigos. Resultados: la persuasión se correlacionó positiva y significativamente con el consumo de alcohol (rs=.272, p<.001). El uso de Facebook se correlacionó positiva y significativamente con el número de publicaciones con contenido de alcohol observadas en los muros o páginas personales de los jóvenes (rs=.165, p<.001) y con el consumo de alcohol (rs=.157, p<.001). Se encontró que el modelo fue significativo (F(9, 429)=58.73, p=.001) con una varianza explicada del 35.1%. Conclusión: se encontró que el sexo, el número de publicaciones con contenido de alcohol y la persuasión muestran un efecto sobre el consumo de alcohol de los jóvenes.
Perfil epidemiológico dos usuários de um Centro de Atenção Psicossocial
Authors: Barbosa Camila Gomes , Meira Paulo Roberto Marinho , Nery Joilda Silva , Gondim Bruno Bezerra
Published: March 2020

Objetivo: analisar as características clínicas e sociodemográficas dos usuários do Centro de Atenção Psicossocial II (CAPS II) do município de Paulo Afonso – Bahia. Método: trata-se de um estudo quantitativo e transversal, realizado a partir do levantamento de dados dos pacientes frequentadores do CAPS II de Paulo Afonso, no ano de 2018. Aspectos clínicos e sociodemográficos foram obtidos a partir dos prontuários médicos dos usuários ativos do serviço cujos anos de cadastramento variaram de 2006 a 2018. Resultados: prevaleceram o sexo feminino, o estado civil solteiro, o Ensino Fundamental incompleto e o analfabetismo, a faixa etária entre 40 e 49 anos, os indivíduos ocupados, a assistência não intensiva e a admissão por encaminhamento. O diagnóstico mais frequente foi do grupo dos transtornos esquizofrênicos, esquizotípicos e delirantes. Os diagnósticos associaram-se significativamente à variável “sexo”, sendo o gênero masculino com maior prevalência de transtornos nos grupos dos transtornos mentais orgânicos, esquizofrenia, transtornos esquizotípicos e delirantes e retardo mental. Já o feminino obteve maior proporção nos transtornos do humor e transtornos neuróticos relacionados com o estresse e somatoformes. Conclusão: os dados obtidos neste estudo possuem relevância para contribuir com o direcionamento de estratégias de aprimoramento e organização do Centro de Atenção Psicossocial de Paulo Afonso.
Tentativa de suicídio e fatores associados ao padrão uso e abuso do álcool
Authors: Cordeiro Eliana Lessa , Silva Liniker Scolfild Rodrigues da , Mendes Emmanuel Wagner Pereira , Silva Luiz Claudio Luna da , Duarte Vanessa Lacerda , Lima Évelyn Cristina Morais Pessôa
Published: March 2020

Objetivo: este estudo teve como objetivo relacionar o padrão de uso, abuso e problemas relacionados ao álcool entre os pacientes que tentaram suicídio em Recife no ano de 2015. Método: trata-se de um estudo transversal, prospectivo, do tipo descritivo, epidemiológico, de abordagem quantitativa, no município do Recife-PE, realizado nas residências dos pacientes que tentaram suicídio e cujo nome consta em notificações compulsórias enviadas para a Vigilância de Atenção a Doenças não Transmissíveis da Secretaria Municipal do Recife. Para a coleta dos dados, aplicou-se oteste AUDIT, por meio de entrevistas, sendo esses dados organizados com o programa EPI-7 e analisados no programa SPSS®, versão 21.0. Resultados: apresentou-se uma prevalência maior em mulheres jovens, com idade média de 38 anos, com 1º grau de escolaridade, cor parda, solteiras, desempregadas e pertencentes à classe social C. No teste AUDIT, 41,4% dos entrevistados encontram-se na zona I, necessitando de aconselhamento aos riscos do consumo de álcool, e 24,1% dos pacientes bebem. Conclusão: os comportamentos suicidas acentuam-se com o uso abusivo do álcool e, por isso, devem ser encarados pelas equipes de saúde com seriedade, respeito e compromisso, pois os agravos e as consequências dessas complicações se tornam ainda mais difíceis quando negligenciados.
Das Problem von Kurz‑ und Langtext in Lk 22,17–20 und das für Marcion bezeugte Evangelium
Authors: Heilmann Jan , Künzl Kevin
Published: March 2020

This article reassesses the evidence for the text critical problem of the so‑called “short and long text” in Luke 22:19b–20. By means of a detailed analysis of the Patristic evidence and a critique of the reconstructions by Harnack, BeDuhn, Roth, and Klinghardt, the authors argue that the Gospel used by Marcion is an overlooked witness for the “short text.” The information that Tertullian gives about Marcion’s text either points directly to the “short text” or to a version of it showing influence from 1 Cor 11:23–25, and, hence, is similar to certain “intermediate” text forms that can be found in the Lukan manuscript tradition.
Gunboat Diplomacy of a Different Kind: Robert H. Pruyn and Japan’s Purchase of U.S. Warships, 1862–1865
Authors: Fessler Susanna
Published: March 2020

This article examines the handling of a contract between the Shogunate of Japan and private agents in the United States for the construction of three ships of war in 1862. Robert H. Pruyn, the U.S. minister, received the original order and down payment from the Japanese government and assigned the contract to two private citizens in Albany, New York. Over the course of the next three years, complications from the U.S. Civil War and fluctuations in the currency markets made it impossible for the U.S. builders to fulfill the order in full; the Japanese received only one ship. Historians consistently have accused Pruyn of mishandling the contract and of using the funds as investment capital for his own personal gain, but evidence shows that Pruyn was scrupulously careful with the contract and the payment, and that he averted a disastrous result which could have soured U.S.-Japan relations.
Music and Materiality
Authors: Lloyd James
Published: March 2020

On the 20th to 22nd July 2018 the 11th MOISA International Conference was held at the University of Reading, organised by Ian Rutherford, Donatella Restani and James Lloyd. Nineteen papers were presented, all engaging with the theme of ‘Music and Materiality’. This report explores the areas where future research on music and materiality might prove fruitful, as evidenced by the rich and varied set of topics and methodologies presented during the conference.
Conservation of the Lyre from Grave 48 in the Area between the So-Called ‘Eriai’ Gates and the Dipylon (470–50 BC)
Authors: Milona Vassiliki
Published: March 2020

This paper focuses on the conservation of the lyre (chelys) of Grave 48, from the area between the so-called ‘Eriai’ Gates and the Dipylon. First, it describes the lifting of the lyre (sound box) from the ground and the recovery of the fragile plaques and fragments from the compact block of soil in the laboratory. Subsequently, it presents the extensive conservation work undertaken by the present writer and her team. Furthermore, it summarizes the conclusions of the X-Radiography and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) examinations of the sound box and the string holder and provides information about the biochemistry, structure and decay of the tortoise shell. In conclusion, the collaboration between conservator and archaeomusicologist, during the remedial conservation treatment, was of great importance, and helped with the identification of the plaques and restoration of the lyre.
Larval morphology of the water mite Hygrobates prosiliensis Koenike, 1915 (Acari, Hydrachnidia, Hygrobatidae)
Authors: TUZOVSKIJ PETR V.
Published: March 2020

The first description of the larval stage of the water mite Hygrobates prosiliens Koenike, 1915 is given, based on larvae reared from populations in European Russia. The results are discussed in comparison with previously published data on larval morphology in the Hygrobates longipalpis group. While the description of larvae given by Wainstein (1980) for H. longipalpis (Hermann, 1804) could in fact refer to that species, a population described by Van Hezewijk & Davids (1985) under the same name probably represents H. prosiliens. Larvae described under this name from Ameriсa by Prasad & Cook (1972) represent a further, probably still undescribed species.
Notes on species of Empididae (Diptera) described by R. Frey from the Swedish Kamchatka Expedition 1920–1922
Authors: SHAMSHEV IGOR V.
Published: March 2020

The type material of eight species of Empididae described by R. Frey in his 1935 paper referring to the Swedish Kamchatka Expedition 1920–1922 of René Malaise are revised: E. (Anacrostichus) pachymorion Frey, E. (A.) vicaria Frey, Empis (Polyblepharis) kamtchatica Frey, E. ( Pachymeria) sjoestedti Frey, Hilara galactoptera Frey, H. ragasides Frey, Rhamphomyia (Pararhamphomyia) albibasis Frey; R. (Ctenempis) malaisei Frey. The lectotype is designated for the following species: Empis (Anacrostichus) pachymorion Frey, 1935; E. (A.) vicaria Frey, 1935; Empis (Pachymeria) sjoestedti Frey, 1935; Hilara ragasides Frey, 1935; Rhamphomyia (Pararhamphomyia) albibasis Frey, 1935; Rhamphomyia (Ctenempis) malaisei Frey, 1935. Six valid species are re-described: Empis (Anacrostichus) pachymorion Frey; E. (Polyblepharis) sjoestedti Frey; Hilara lactescens Frey (= H. galactoptera Frey); H. ragasides Frey; Rhamphomyia (Pararhamphomyia) albibasis Frey; R. (Ctenempis) malaisei Frey.
Soluble Carbon Nanotubes and Their Applications
Authors: Murakami Hiroto , Nakashima Naotoshi
Published: March 2020

Carbon nanotubes (CNTs) have been the forefront of nanoscience and nanotechnology due to their unique electrical and mechanical properties and specific functions. However, due to their poor solubility in solvents, the applications using the materials have been limited. Therefore, strategic
approaches toward the solubilization of CNTs are important in wide fields including chemistry, physics, biochemistry, biology, pharmaceuticals, and medical sciences. In this article, we summarize: (i) the strategic approaches toward the solubilization of CNTs using chemical and physical modifications,
(ii) nanocomposites of CNTs and biological molecules including DNA, (iii) formation of CNTs with topological structures, (iv) separation of metallic and semiconducting nanotubes, (v) the preparations of films and fibers of CNTs and hybrid materials of CNTs and organic and inorganic molecules.
Nickel Oxide Nanotubes: Synthesis and Electrochemical Performance for Use in Lithium Ion Batteries
Authors: Needham S. A. , Wang G. X. , Liu H. K. , Yang L.
Published: March 2020

Uniform and aligned Nickel Oxide (NiO) nanotube bundles have been synthesized by a template process. Individual nanotubes are 60 μm long with a 200 nm outer diameter and wall thickness of 20–30 nm. The synthesis involved forming Ni(OH)2 nanotubes that were
subsequently heated to 350°C in order to fully convert the product to NiO nanotubes. NiO nanotube powder was used in lithium-ion cells for assessment of lithium storage ability and electrochemical performance. Discharge capacity of the NiO nanotube electrode was in excess of 30% higher
than that of the standard NiO nanocrystalline powder electrode after 20cycles. Impedance data suggests the NiO nanotube electrode provides more controlled and sustainable Li diffusion when compared to the NiO reference powder electrode system.
Fabrication of Aligned Poly(vinyl alcohol) Nanofibers by Electrospinning
Authors: Chuangchote Surawut , Supaphol Pitt
Published: March 2020

Electrospinning has become a versatile tool for fabricating nanofibers from materials of diverse origins. Normally, mats of randomly-aligned fibers were obtained. A number of techniques have been proposed to arrive at uniaxially-aligned fibers. This work reports a new technique, i.e.,
dual vertical wire technique, for fabrication of uniaxially-aligned fibers. This technique utilized two stainless steel wires that were vertically set in a parallel manner between a charged needle and a grounded collector plate. This technique allowed simultaneous collection of aligned fibers
(between the parallel vertical wires) and a randomly-aligned fiber mat (on the collector plate). Application of the technique on poly(vinyl alcohol) (PVA) to prepare uniaxially-aligned fibers was found to be successful at short collection times. Unexpected formation of a large fiber tow consisting
of individual as-spun nanofibers that were bound into a bundle was observed at long collection times. Morphological appearance and size of the fiber tow was affected by the change in the distance between the two vertical wire electrodes, while the average diameter of the individual fibers
was not (i.e., about 340 to 350 nm). Lastly, mechanical properties and thermal behavior of the fiber tow were also investigated.
Numerical Analysis on a Passive Chaotic Micromixer with Helical Microchannel
Authors: Wang Ruijin , Lin Jianzhong
Published: March 2020

In order to improve the mixing efficiency, the diffusion and mixing of species in the helical micro-mixer are simulated numerically. The results show that the mixing efficiency in the helical micro-mixer is much higher than that in the straight micro-channel and obviously higher than
that in the serpentine micro-channel when Reynolds number is low. At high Reynolds number, even though the mixing efficiency in the helical micro-mixer is still much higher than that in the straight micro-channel, no obvious difference of mixing efficiency in the helical micro-mixer and serpentine
micro-channel is found. The conclusions are helpful to optimize the structure of the micro-mixer.
Enhancement of Green Electroluminescence from Nanocrystalline Silicon by Wet and Dry Processes
Authors: Sato Keisuke , Hirakuri Kenji
Published: March 2020

Correlation between defects and luminescence property from electroluminescent (EL) device composed of nanocrystalline silicon (nc-Si) prepared by wet and dry processes such as hydrofluoric (HF) acid solution treatment and annealing have investigated using electron spin resonance and
EL measurements. The EL device using HF-treated nc-Si emitted strong red light, because of existence of only P′ce-centers (radiative recombination centers) on the surface vicinity. On the other hand, the EL device using annealed nc-Si above 400 °C exhibited green luminescence
by the reduction of particle size due to surface oxidation. When the annealing temperature was risen from 400 °c up to 600 °c, the green luminescence strengthened with increasing the P′ce-centers. These results indicate that the formation of many radiative recombination
centers onto the nc-Si surface vicinity lead to the enhancement of green luminescence from the nc-Si based EL device.
Influence of Oxidized Layer on Operating Voltage and Luminance of Nanocrystalline Silicon Electroluminescent Device
Authors: Sato Keisuke , Hirakuri Kenji
Published: March 2020

A direct current (DC) operating voltage and luminescence property of red electroluminescent (EL) devices with and/or without a silicon dioxide (SiO2) layer at interface between nanocrystalline Si(nc-Si) region and Si substrate has investigated. The removal of SiO2
layer in the EL device led to the lowering of DC operating voltage from 4.0 up to 2.0 V and the increase of luminescence intensity more than one order of magnitude. The external quantum efficiency of red luminescence from the EL device without the SiO2 layer at the DC operating
voltage of 3.0 V was 0.5%. These were realized by the efficient and easy injection of carriers to the radiative recombination centers in the nc-Si region due to the removal of SiO2 layer. These results indicate that the removal of SiO2 layer is drastically improved the
DC operating voltage and luminescence intensity for the nc-Si based EL device.
Capacity of Nano-Reactors of AOT Micro-Emulsions to Form and Sustain Ultra Small Semiconductor Quantum Dots
Authors: Sawant Prashant D. , Ramaniah Lavanya M. , Manohar C.
Published: March 2020

Microemulsions (MEs) are increasingly being used as nano-reactors for the formation and synthesis of nanoparticles or quantum dots (QDs). In this paper, we study the capacity of aqueous nanoreactors of AOT microemulsions for the formation of ultrasmall semiconductor QDs by fixing w
= ([H2O]/[AOT]) and varying the concentration of CdS up to 100 mM. The CdS QDs in the MEs are evaluated using UV-vis spectroscopy, XRD, TEM, and light scattering. Particles are found to be controlled in 8.7 Å–11.8 Å. The UV-vis spectra are analysed using an accurate
tight-binding (TB) approach and effective mass approximation (EMA). The TB method, being much more accurate than the EMA, gives results in good agreement with X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD reveals that the particles are mostly zinc-blend at low concentrations
(≥20 mM) but a mixture of zinc-blend and wurtzite at higher concentrations (100 mM). High concentrations of CdS are useful to improve the yield while best-utilizing nanoreactors and to give a tight control over size and polydispersity. MEs containing CdS are found to be stable over a month
when kept in the dark.
Ultra-Smooth Nanostructured Diamond Films Deposited from He/H2/CH4/N2 Microwave Plasmas
Authors: Konovalov Valery V. , Melo Andrew , Catledge Shane A. , Chowdhury Shafiul , Vohra Yogesh K.
Published: March 2020

Addition of He to a high CH4 content (10.7 vol%) H2/CH4/N2 feedgas mixture for microwave plasma chemical vapor deposition produced hard (58–72 GPa), ultra-smooth nanostructured diamond films on Ti-6Al-4V alloy substrates. Upon increase
in He content up to 71 vol%, root mean squared (RMS) surface roughness of the film decreased to 9–10 nm and average diamond grain size to 5–6 nm. Our studies show that increased nanocrystallinity with He addition in plasma is related to plasma dilution, enhanced fragmentation of
carbon containing species, and enhanced formation of CN radical.
Morphology and Size Dependent Optical Properties of CdS Nanostructures
Authors: Kar Soumitra , Panda S. K. , Satpati B. , Satyam P. V. , Chaudhuri S.
Published: March 2020

CdS nanoparticles with different sizes ranging from 2.5 nm to 300 nm and nanorods with aspect ratio ∼32 were synthesized by simple solvothermal process with a view to explore the effect of size and shape on the optical properties of these nanoforms. Solvent, temperature and the
Cd source played important role in determining the morphologies and sizes of the nanocrystals. Comparative study of the optical properties of these nanoforms showed systematic changes in the optical absorption spectra with the reduction in particle size. Nanorods showed bulk like properties.
Photoluminescence and Raman studies were carried out to explore the size and morphology dependent optical properties of the CdS nanoforms.
Synthesis and Electrical Properties of (Bi1/2Na1/2)TiO3(BNT) Ferroelectric Thin Films by Liquid Sprayed Mist Chemical Vapor Deposition Technique
Authors: Kim Bok-Hee , Kim Sang-Hee , Kim Jong-Hwan , Lee Kun-Jae , Choa Yong-Ho , Choi Youn-Kyu , Kim Spencer S.
Published: March 2020

This study aims to synthesize lead-free ferroelectric material, (Bi1/2Na1/2)TiO3 using the Liquid Sprayed Mist Chemical Vapor Deposition (LSMCVD) technique. The mist of precursor solution was vaporized and deposited on two different substrates of Si(100)
and (111)Pt/TiO2/SiO2/Si(100) in an oxygen atmosphere. The deposition temperature and time were varied in the range of 400–600 °C and 30–90 min. (Bi1/2Na1/2TiO3 thin film had preferred orientations of (110). The thickness
of the thin film deposited was 35–162 nm. The remnant polarization (2Pr) and the dielectric constant were 4.6–16.8 μC/cm2, 325–350, respectively.
Fabrication and Optical Characteristics of a Novel Optical Fiber Doped with the Au Nanoparticles
Authors: Ju Seongmin , Nguyen Viet Linh , Watekar Pramod R. , Kim Bok Hyeon , Jeong Chaehwan , Boo Seongjae , Kim Cheol Jin , Han Won-Taek
Published: March 2020

Optical fibers containing gold metal nanoparticles were developed by modified chemical vapor deposition, in which Au(OH)3 and tetraethyl-orthosilicate (TEOS) was used via sol–gel process to incorporate gold metals by providing the reduction atmosphere. The absorption
peak appeared near 490 nm was found to be due to the surface plasmon resonance of the gold nanoparticles incorporated in the fiber core.
Ta2O5-Incorporated WO3 Nanocomposite Film for Improved Electrochromic Performance in an Acidic Condition
Authors: Shim Hee-Sang , Ahn Hyo-Jin , Kim Youn-Su , Sung Yung-Eun , Kim Won Bae
Published: March 2020

We report electrochromic and electrochemical properties of a WO3-Ta2O5 nanocomposite electrode that was fabricated from co-sputtering. Transmission electron microscopy (TEM)images of the WO3-Ta2O5 nanocomposite electrode
revealed that morphology of the WO3 film was changed by incorporation of Ta2O5 nanoparticles, and their chemical states were confirmed to be W6+ and Ta5+ oxides from X-ray photoelectron spectroscopy (XPS). The introduction of Ta2O5
to the WO3 film played a role in alleviating surface roughness increase during continuous potential cycling; whereas the surface roughness of the WO3 film was increased from ca. 3.0 nm to ca. 13.4 nm after 400 cycles, the roughness increase on the WO3-Ta2O5
was significantly reduced to 4.2 nm after 400 cycles, as investigated by atomic force microscopy (AFM). This improvement of the stability by adding Ta2O5 may be responsible for the enhanced electrochemical and optical properties over long-term cycling with the WO3-Ta2O5
nanocomposite electrode.
Growth of Well-Aligned ZnO Nanorods Using AuGe Catalyst by Vapor Phase Transportation
Authors: Ha S. Y. , Jung M. N. , Park S. H. , Ko H. J. , Ko H. , Oh D. C. , Yao T. , Chang J. H.
Published: March 2020

Well-aligned ZnO nanorods have been achieved using new alloy (AuGe) catalyst. Zn powder was used as a source material and it was transported in a horizontal tube furnace onto an AuGe deposited Si substrates. The structural and optical properties of ZnO nanorods were characterized by
scanning electron microscopy, high resolution X-ray diffraction, and photoluminescence. ZnO nanorods grown at 650 °C on 53 nm thick AuGe layer show uniform shape with the length of 8±0.5 μm and the diameter of 150±5 nm. Also, the tilting angle of ZnO nanorods (±5.5°)
is confirmed by HRXRD. High structural quality of the nanorods is conformed by the photoluminescence measurement. All samples show strong UV emission without considerable deep level emission. However, weak deep level emission appears at high (700 °C) temperature due to the increase of
oxygen desertion.
Tango Binary Search Tree Based Asymmetric Cryptographic Sensor Node Authentication for Secured Communication in Wireless Sensor Networks
Authors: Cynthia Antony , Saravanan V.
Published: March 2020

Wireless sensor network (WSN) comprises the group of sensor nodes distributed to sense and monitor the environments and collects the data. Due to the distributed nature of the sensor nodes, security is a major role to access the confidential data and protect the unauthorized access.
In order to improve the secure communication, authentication is essential process in WSN. A Tango Binary Search Tree based Schmidt Cryptographic Sensor Node Authentication (TBST-SCSNA) technique is introduced for secured data communication in WSN with higher authentication accuracy. Initially,
the trust values for each sensor nodes are calculated for increasing the security in data communication. The sensor nodes in WSN are arranged in tango binary search tree based on the trust value. The nodes in tree are inserted or removed based on their deployment. After that, the Schmidt-Samoa
cryptographic technique is applied for node authentication and secure data communication. The cryptographic technique comprises three processes key generation, encryption and decryption. In key generation phase, the public key (i. e., node_ID) are generated and distributed for the sensor nodes
and private key is kept secret using Schmidt-Samoa algorithm. The root node is embedded with a key during the deployment and it is controlled the entire the sensor nodes in the path. A Parent node generates the keys for child node based on the ID of parent node. After the key generation, the
sender node encrypts the data packet and transmits to receiver node in the tree with the receiver node ID. After that, the receiver node enters their private key and verifies it with already stored key at the time of key generation. If both keys are same, then the node is said to be authentic
node. Otherwise, the sensor node is said to be a malicious node. The authentic node only receives the original data packets. This process gets repeated till all the nodes in the path verify their identities and performs the secure communication. Simulation is carried out with different parameters
such as authentication accuracy, authentication time and security level with respect to a number of sensor nodes and a number of data packets. The results observed that the TBST-SCSNA technique efficiently improves the node authentication accuracy, security level with minimum time than the
state-of-the-art-methods.
Development and Characterization of Polydiphenylamine/CuO Nanohybrid Electrode and Its Improved Electrochemical Properties
Authors: Lakshmi M. Suba , Muthusankar E. , Wabaidur Saikh Mohammad , Alothman Zeid Abdullah , Ponnusamy Vinoth Kumar , Ragupathy D.
Published: March 2020

This reveals the synthesis, characterization and electrochemical studies of copper oxide (CuO) dispersed in polydiphenylamine (PDPA) matrix modified indium tin oxide (ITO/PDPA/CuO) nanohybrid electrode was fabricated using electrochemical deposition method. The structural morphology
was captured through Field emission scanning electron microscopy (FESEM) and the confirmation of nanocomposites material of PDPA/CuO was achieved by Energy-dispersive X-ray spectroscopy (EDX). The electrochemical performance of (ITO/PDPA/CuO) modified nanohybrid electrode was investigated
by Cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS). The enhanced electrocatalytic activity of (ITO/PDPA/CuO) was due to the synergistic interaction of diphenoquinone diamine (DPDI2+) and CuO. Nyquist plot received from EIS ensures the enrichment of a fast
electron transfer rate and can be used for various applications.
A Spectral Data Compression (SDCOMP) Radiative Transfer Model for High-Spectral-Resolution Radiation Simulations
Authors: Liu Chao , Yao Bin , Natraj Vijay , Weng Fuzhong , Le Tianhao , Shia Run-Lie , Yung Yuk L.
Published: March 2020

With the increasing use of satellite and ground-based high-spectral-resolution (HSR) measurements for weather and climate applications, accurate and efficient radiative transfer (RT) models have become essential for accurate atmospheric retrievals, for instrument calibration, and to provide benchmark RT solutions. This study develops a spectral data compression (SDCOMP) RT model to simulate HSR radiances in both solar and infrared spectral regions. The SDCOMP approach “compresses” the spectral data in the optical property and radiance domains, utilizing principal component analysis (PCA) twice to alleviate the computational burden. First, an optical-property-based PCA is performed for a given atmospheric scenario (atmospheric, trace gas, and aerosol profiles) to simulate relatively low-spectral-resolution radiances at a small number of representative wavelengths. Second, by using precalculated principal components from an accurate radiance dataset computed for a large number of atmospheric scenarios, a radiance-based PCA is carried out to extend the low-spectral-resolution results to desired HSR results at all wavelengths. This procedure ensures both that individual monochromatic RT calculations are efficiently performed and that the number of such computations is optimized. SDCOMP is approximately three orders of magnitude faster than numerically exact RT calculations. The resulting monochromatic radiance has relative errors less than 0.2% in the solar region and brightness temperature differences less than 0.1 K for over 95% of the cases in the infrared region. The efficiency and accuracy of SDCOMP not only make it useful for analysis of HSR measurements, but also hint at the potential for utilizing this model to perform RT simulations in mesoscale numerical weather and general circulation models.
Synthesis of developed rice straw sheets and glass fiber-reinforced polyester composites
Authors: Megahed M , Ali-Eldin Soliman S , Abd El Moezz Sara M , Abdalla WS
Published: March 2020

In this study, a sheet of random rice straw fiber was developed. These rice straw sheets were used to reinforce polyester matrix. Synthesis of rice straw sheets and glass fibers as synthetic fibers-reinforced polyester composites were investigated. Several new stacking sequences were fabricated with random glass fiber mats with different areal densities (225 g/m2, 300 g/m2, and 450 g/m2) and rice straw sheets. The specific mechanical properties of these natural/synthetic fiber composites were investigated. Scanning electron microscopy was used to study the morphology of the fracture surfaces of the fabricated hybrid composites. Experimental results showed that specific tensile and flexural stiffness of rice straw fiber composite is better those obtained with glass fiber composites. The hybrid natural/synthesis composites with alternating glass fiber mat with areal densities 300 g/m2, and rice straw shows higher specific tensile strength than rice straw and other hybrid composites. Hybrid composites with high areal density on the outer surfaces yield a significant increase in flexural-specific strength and hardness as compared to other fabricated composites.