bluuebunny/crossref_metadata_2025 huggingface dataset:
Collisionless Heat Flux Regulation via the Electron Firehose Instability in the Presence of a Core and Suprathermal Population in the Expanding Solar Wind
Authors: Innocenti Maria Elena , Boella Elisabetta , Tenerani Anna , Velli Marco
Published: July 2020

The evolution of the electron heat flux in the solar wind is regulated by the interplay between several effects: solar wind expansion, which can potentially drive velocity–space instabilities, turbulence, wave–particle interactions, and, possibly, collisions. Here we address the respective role played by the solar wind expansion and the electron firehose instability (EFI), developing in the presence of multiple electron populations, in regulating the heat flux. We carry out fully kinetic, expanding box model simulations and separately analyze the enthalpy, bulk, and velocity distribution function skewness contributions for each of the electron species. We observe that the key factor determining electron energy flux evolution is the reduction of the drift velocity of the electron populations in the rest frame of the solar wind. In our simulations, redistribution of the electron thermal energy from the parallel to the perpendicular direction after the onset of the EFI is observed. However, this process seems to impact energy flux evolution only minimally. Hence, reduction of the electron species drift velocity in the solar wind frame appears to directly correlate with efficiency for heat flux instabilities.
CTCV J2056-3014: An X-Ray-faint Intermediate Polar Harboring an Extremely Fast-spinning White Dwarf
Authors: Lopes de Oliveira R. , Bruch A. , Rodrigues C. V. , Oliveira A. S. , Mukai K.
Published: July 2020

We report on XMM-Newton X-ray observations that reveal CTCV J2056-3014 to be an unusual accretion-powered, intermediate polar (IP) system. It is a member of the class of X-ray-faint IPs whose space density remains unconstrained but potentially very high, with L

x,0.3–12 keV of 1.8 × 1031 erg s−1. We discovered a coherent 29.6 s pulsation in X-rays that was also revealed in our reanalysis of published optical data, showing that the system harbors the fastest-spinning, securely known white dwarf (WD) so far. There is no substantial X-ray absorption in the system. Accretion occurs at a modest rate (∼6 × 10−12
M
⊙ yr−1) in a tall shock above the WD, while the star seems to be spinning in equilibrium and to have low magnetic fields. Further studies of CTCV J2056-3014 potentially have broad implications on the origin of magnetic fields in WDs, on the population and evolution of magnetic cataclysmic variables, and also on the physics of matter around rapidly rotating magnetic WDs.
Checklist of thallus-forming Laboulbeniomycetes from Belgium and the Netherlands, including Hesperomyces halyziae and Laboulbenia quarantenae spp. nov.
Authors: Haelewaters Danny , Kesel André De
Published: July 2020

In this paper we present an updated checklist of thallus-forming Laboulbeniomycetes (Ascomycota, Pezizomycotina), that is, the orders Herpomycetales and Laboulbeniales, from Belgium and the Netherlands. Two species are newly described based on morphology, molecular data (ITS, LSU ribosomal DNA) and ecology (host association). These areHesperomyces halyziaeonHalyzia sedecimguttata(Coleoptera, Coccinellidae) from both countries andLaboulbenia quarantenaeonBembidion biguttatum(Coleoptera, Carabidae) from Belgium. In addition, nine new country records are presented. For Belgium:Laboulbenia aubryionAmara aranea(Coleoptera, Carabidae) andRhachomyces spinosusonSyntomus foveatus(Coleoptera, Carabidae). For the Netherlands:Chitonomyces melanurusonLaccophilus minutus(Coleoptera, Dytiscidae),Euphoriomyces agathidiionAgathidium laevigatum(Coleoptera, Leiodidae),Laboulbenia fasciculataonOmophron limbatum(Coleoptera, Carabidae),Laboulbenia metabletionSyntomus foveatusandS. truncatellus(Coleoptera, Carabidae),Laboulbenia pseudomaseionPterostichus melanarius(Coleoptera, Carabidae),Rhachomyces canariensisonTrechus obtusus(Coleoptera, Carabidae), andStigmatomyces hydrelliaeonHydrellia albilabris(Diptera, Ephydridae). Finally, an identification key to 140 species of thallus-forming Laboulbeniomycetes in Belgium and the Netherlands is provided. Based on the combined data, we are able to identify mutual gaps that need to be filled as well as weigh the impact of chosen strategies (fieldwork, museum collections) and techniques in these neighboring countries. The aim of this work is to serve as a reference for studying Laboulbeniomycetes fungi in Europe.
Xylella fastidiosa invasion of new countries in Europe, the Middle East and North Africa: Ranking the potential exposure scenarios
Authors: Frem Michel , Chapman Daniel , Fucilli Vincenzo , Choueiri Elia , El Moujabber Maroun , La Notte Pierfederico , Nigro Franco
Published: July 2020

After the recent high-impact European outbreaks of Xylella fastidiosa (Xf), a xylem-limited plant pathogenic bacterium native to the Americas, this research aims to rank the risks of potential entry, establishment and spread of Xf in new countries across Europe, the Middle East and North Africa. A novel risk-ranking technique is developed, based on combining entry risk drivers (imported plants, direct flights and ferry connections) with risk factors related to establishment and spread (presence of potential insect vectors, vulnerable economic crops, alternative hosts and climate suitability) of this pathogen. This reveals that western European countries have the highest risk for entry, but that the Mediterranean basin runs the highest risk for establishment and spread of Xf. Lebanon in particular has the highest level of risk for Xf dispersal within its suitable territory. Countries without current outbreaks combining high risks of Xf arrival and establishment are mainly in the Mediterranean basin: Turkey is at the highest level of risk, followed by Greece, Morocco and Tunisia, which are ranked at the high level. The ranking model also confirms the vulnerability, in terms of invasion by Xf, of southern European countries (Italy, Portugal and Spain) in which the pathogen has already been reported. High summer temperatures in these southern countries are likely to be the significant determinant for the overall invasion process, while northern European countries have a high level risk for the arrival of the pathogen, but relatively low summer temperatures may limit establishment and spread of major outbreaks. In general, our study provides a useful approach for mapping and comparing risks of invasive non-native species and emerging pathogens between countries, which could be useful for regional horizon scanning and phytosanitary and biosecurity management.
Des mots et des hommes
Authors: Sacchelli Muriel
Published: July 2020

La nouvelle terminologie qui s’est progressivement imposée dans l’éducation spécialisée, loin de ne constituer qu’un habillage cosmétique, vient signer la mutation majeure en cours dans ce champ. L’adoption et l’intériorisation par les travailleurs sociaux d’une novlangue faite de vocables empruntés à l’entreprise marchande risquent de réduire l’acte éducatif à une entreprise de normalisation déshumanisante, évacuant les dimensions de la clinique, de l’inconscient et du symptôme.
La clinique de la parole au temps du néolibéralisme
Authors: Sauret Marie-Jean
Published: July 2020

L’auteur nous interroge sur ce qui fait lien, aujourd’hui, dans une société marquée par le scientisme et le néolibéralisme. Qu’en est-il des conséquences sur l’acte de parole, sur les signifiants qui nous gouvernent au plus près de notre « être » ? L’une des pistes de résistance possible pour éviter une déshumanisation serait de pouvoir distinguer ce qui relève de notre « plus-de-jouir » et de la « plus-value » marxiste spécifique de la logique consumériste.
Lorsque glissent les mots de la tribu...
Authors: Rouzel Joseph
Published: July 2020

Les glissements de la langue imposés par un pouvoir inaugurent toujours un changement de statut de la société et des citoyens. Et nous sommes bien plongés, à travers les « éléments de langage » des politiques, mais aussi les dérives que l’on voit poindre dans tous les secteurs de travail, notamment le travail social et le soin, dans un tel changement. Ainsi dans certains établissements sociaux et médico-sociaux du glissement dans la nomination de « réunion de synthèse » à « réunion de projet ».
Le « bel ouvrage » à reconquérir
Authors: Marchal Jean-Luc
Published: July 2020

Cet article vient interroger l’infiltration des logiques managériales dans le champ large de la santé, du social, avec son lot d’injonctions normalisatrices, d’évaluations chiffrées, du processus de déconnexion criant entre les dirigeants et les gens du métier avec pour effets des attaques du sens du métier. Il plaide ici pour une reconquête du « bel ouvrage » pour renverser la dictature des normes.
Se jouer des mots
Authors: Caris Rozenn
Published: July 2020

Face au parasitage de mots issus du langage technocratique qui circulent en réunion, ce texte raconte comment, en équipe, un jeu s’est instauré en mobilisant la créativité et une mise en dérision subtile et salutaire pour les pratiques.
Les échos du trauma sur les professionnels qui accompagnent les mineurs étrangers isolés
Authors: Stévenin Frédérique
Published: July 2020

Cet article se propose d’aborder une forme de souffrance au travail particulière, liée à la relation d’aide. En nous basant sur la notion d’acquisition vicariante, qui consiste à apprendre par observation, nous rejoignons l’hypothèse selon laquelle l’écoute des récits de vie de ces jeunes produirait des effets divers sur ceux qui les reçoivent, selon la place qu’ils occupent, leurs missions, mais également selon qui ils/elles sont. Le travail auprès d’un groupe de jeunes exilés, pris en charge dans un dispositif d’accompagnement, nous a permis d’observer des effets de stress professionnel qui s’originent dans le matériel traumatique apporté par les bénéficiaires. Le traumatisme, vécu par procuration, affecte les accompagnants, notamment en bousculant leurs valeurs, leurs convictions, en modifiant leur rapport au monde.
Courts-circuits et circuits courts
Authors: Deloche Sandrine
Published: July 2020

Une des voies de résistance exigeant la sauvegarde d’une psychiatrie humaniste consiste à défendre le soin psychique dans sa visée écologique : accueillir la diversité du vivant, prendre soin du milieu, écouter la singularité de chacun, s’engager sur la durée. En somme, la remise sur pied du dispositif sectoriel tel qu’il fut pensé à son origine. Une offre locale en circuit court répondant aux besoins de la cité et non aux attendus hors-sol d’une manne techno-financière qui nous mène dans le mur.
Les encours du savoir. Circulation et statut des connaissances en établissement spécialisé
Authors: Decourchelle Denis
Published: July 2020

Les établissements spécialisés accueillant des personnes dépendantes font appel à des savoirs spécifiques permettant de rationaliser leur pratique. Pour autant, les professionnels qui en font partie peuvent élaborer, à certaines conditions, des échanges coopératifs de connaissances et valoriser ainsi leurs activités.
MDR
Authors: Juliot Lucie
Published: July 2020

La dernière version cinématographique du Joker s’impose comme un chef d’œuvre et nous rappelle, comme le disait Lacan, comme l’artiste précède le psychanalyste ( Autres écrits , 2001). Bien que production fictive, le personnage, abordé depuis le prisme de l’enfance maltraitée, nous amène à interroger les inventions du sujet pour tenir dans le monde. Nulle légitimation de l’acte mais une fine anamnèse qui permet le repérage des coordonnées du pire. Le clinicien ne sortira probablement pas indemne de cette séance de cinéma. Y résonne la complexité de la pratique clinique auprès des enfants et des adolescents chez qui le symptôme éclaire parfois le désordre familial qui serait au reflet de celui du monde. Le cas de Tim nous engagera à réfléchir à ces problématiques.
Une expérience de travailleuse pair…
Authors: Santiago Sanz Henri
Published: July 2020

Dans cet entretien réalisé avec une médiatrice de La Case de santé de Toulouse, celle-ci relate son parcours personnel jusqu’à son expérience de médiatrice puis de future professionnelle.
Workplace STRESS Among Psychiatric Nurses
Authors: Robinson J Renée , Clements Karen , Land Colleen
Published: July 2020

Prevalence, Distribution, Correlates, & Predictors

ABSTRACT

Vicarious trauma and burnout are serious manifestations of workplace stress. Both can have substantial consequences for health care professionals, health services, and consumers. This article reports results of a study examining the prevalence, distribution, correlates, and predictors of vicarious trauma and burnout among registered psychiatric nurses (RPNs). A survey was distributed to all practicing RPNs in Manitoba, Canada (N = 1,015). The survey contained the Maslach Burnout Inventory, the Traumatic Stress Institute Belief Scale (i.e., a measure of vicarious trauma), and a section on symptoms of posttraumatic stress disorder (PTSD). The RPNs were found to be experiencing high levels of emotional exhaustion (i.e., high burnout) and even higher levels of personal accomplishment (i.e., low burnout). No significant differences were found between respondents' total scores on the Traumatic Stress Institute Belief Scale and instrument norms for mental health care professionals. Predictors of burnout and vicarious trauma also are presented in this article. Stress experienced by RPNs, as well as strengths on which to build, clearly are evident in the study results. Strategies for reduction in workplace stress may benefit psychiatric nurses, clients, and health services.
ACTIVITY COMMAND ENCODING OF CEREBRAL CORTEX M1-EVOKED POTENTIALS OF THE SPRAGUE DAWLEY RAT USING TIME DELAY NEURAL NETWORKS
Authors: Kuo Tung-Tai , Lo Rong-Chin , Lee Ren-Guey , Chen Yuan-Hao , Cai Shang-Hsien
Published: July 2020

Understanding the neurons that transmit messages in the brain while we thinking, feeling, or acting is critical for research on the causes of neurological disease and treatment strategies. This research focuses on the primary motor cortex M1 region, which is involved in human motor function as an activity command center. Understanding this region can help us to determine the mechanism of movement control by the brain, with applicability to other activity mechanisms. A time delay neural network (TDNN) is a suitable model for studying brain signals. TDNN can analyze comprehensive information for a period of successive signals, which is similar to the transmission mechanism of the M1 region. Therefore, this study used a TDNN to build a three-stage encoding system corresponding to the signal type, type arrangement, and time sequence of the brainwave signal from the M1 region and the encoded results were defined as codes, symbols, and commands, respectively. This study aimed to understand the relationship between movement and the M1 region by decoding the signal when the rat undertakes an action. First, we recorded the M1 signal from three rat action types (walk, stand up, and shift head) and performed signal processing. This included using a nonlinear energy operator to find the response points of each action signal. The signals were separated into several sections according to the response time points and independent component analysis was then used to extract the features of the signal (the signal of interest). Finally, we found 16 representative sample signals through a dynamic dimension increasing algorithm to train a three-stage TDNN. We then input the remaining feature signals of interest into the three-stage TDNN for encoding and classification. The results showed an accuracy rate for the three actions of 51.4%, 80.0%, and 54.3%, which means that it is feasible to explain the brain signal of M1 from the free-moving animal using a three-stage TDNN encoding model.
A TECHNOLOGY OF RENOGRAM DIVIDING BASED ON BLOOD VESSELS TO OBTAIN A MORE ACCURATE DIAGNOSIS
Authors: Lo Rong-Chin , Kuo Tung-Tai , Lee Ren-Guey , Chen Yuan-Hao , Huang Chih-Yin
Published: July 2020

Nuclear medicine could provide an accurate estimate of the biochemical composition, metabolism, and capability of the kidney. Using nuclear medicine imaging to scan the organ, we can find the time-activity curve, called a renogram, by the intensity of the image. The activity curve can be employed to describe organ capability. Traditional methods of observing the activity curve of the whole kidney can obscure some small details. This paper proposes an improved renogram based on blood vessel distribution to estimate the kidney capability automatically. Every patient must acquire 180 renal dynamic images from the renal scan. First, acquiring region of the kidney in the No. 68 kidney image and correcting the background of this sample image, the sample image will be applied to the rest of the images to find the region of the kidney. The kidney image is then divided into several sub-regions according to the paths of the blood vessels from No. 50 kidney image. For each sub-region, we find the time–intensity curve, called the sub-renogram. Then, we observe the activity curves of the sub-region and the whole kidney separately to assist the diagnosis. The results of the automatic analysis are similar to the traditional methods used on the whole kidney, which ignores any abnormal sub-region activity. The proposed method can improve the accuracy of the doctor’s diagnosis.
Prototype of a Low-Cost Impedance Tomography Based on the Open-Hardware Paradigm
Authors: Ribeiro David Edson , Barbosa Valter Augusto de Freitas , Lins de Lima Clarisse , Emmanuel de Souza Ricardo , Pinheiro dos Santos Wellington
Published: July 2020

Electrical Impedance Tomography (EIT) is a noninvasive, painless, and ionizing radiation-free technique for image acquisition of a region of interest. It is performed through electrical parameters. The method is based on the application of an alternating electric current pattern of low intensity through electrodes arranged around the surface region in order to obtain the image and also to measure the excitation electrical potentials. The aim of this study is to develop a device based in open hardware. Furthermore, the authors aim to build a prototype of a data acquisition system based on EIT. This device is the first step to obtain a complete and portable tomography equipment at a low cost.
Classification of Breast Lesions in Frontal Thermographic Images Using a Diagnosis Aid Intelligent System
Authors: Araújo de Santana Maíra , Pereira Jessiane Mônica Silva , Lins de Lima Clarisse , Jacinto de Almeida Maria Beatriz , Silva de Andrade José Filipe , Silva de Souza Thifany Ketuli , Fernandes de Lima Rita de Cássia , Pinheiro dos Santos Wellington
Published: July 2020

This study aims to assess the breast lesions classification in thermographic images using different configuration of an Extreme Learning Machine network as classifier. In this approach, the authors changed the number of neurons in the hidden layer and the type of kernel function to further explore the network in order to find a better solution for the classification problem. Authors also used different tools to perform features extraction to assess both texture and geometry information from the breast lesions. During the study, the authors found that the results changed not only due to the network parameters but also due to the features chosen to represent the thermographic images. A maximum accuracy of 95% was found for the differentiation of breast lesions.
Feature Selection Based on Dialectical Optimization Algorithm for Breast Lesion Classification in Thermographic Images
Authors: Pereira Jessiane Mônica Silva , Araújo de Santana Maíra , Lins de Lima Clarisse , Fernandes de Lima Rita de Cássia , Lopes de Lima Sidney Marlon , Pinheiro dos Santos Wellington
Published: July 2020

Breast cancer is the leading cause of death among women worldwide. Early detection and early treatment are critical to minimize the effects of this disease. In this sense, breast thermography has been explored in the process of diagnosing this type of cancer. Furthermore, in an attempt to optimize the diagnosis, intelligent pattern recognition techniques are being used. Features selection performs an essential task in this process to optimize these intelligent techniques. This chapter proposes a features selection method using Dialectical Optimization Method (ODM) associated to a KNN classifier. The authors found that this combination proved to be a good approach showing a low impact on breast lesion classification performance. They obtained around 5% decrease in accuracy, with a reduction of about 46.80% of the features vector. The specificity and sensitivity values they found were competitive to other widely used methods.
Thermography in Biomedicine
Authors: Nola Iskra Alexandra , Kolarić Darko
Published: July 2020

The historical details are important to understand the development and application of thermography with particular emphasis on its application in medicine, explained on breast cancer detection. Today, recommendations for breast cancer include the use of mammography as the gold standard screening method. In public health, the importance of screening women for possible breast cancer is indisputable, especially in light of the fact that the size of the cancer directly corresponds to the success of the cure. A method that will allow early detection of cancer and/or successful follow-up of postoperative or adjuvant treatment is unquestionable. Thermography as a non-invasive method is harmless and therefore enables repetition without harmful radiation to the patient, unlike mammography. These features should be sufficient to empower its application. However, its breakthrough does not proceed as expected. This chapter particularly emphasizes the importance of conducting studies in a uniform manner to enable the collected data to be comparable appropriately with the methods used so far.
Imaging Techniques for Breast Cancer Diagnosis
Authors: Saha Debasray , Vaishnav Neeraj , Jha Abhimanyu Kumar
Published: July 2020

Breast cancer is the most typical variety of cancer in women worldwide. Mammography is the “gold standard” for the analysis of the breast from an imaging perspective. Altogether, the techniques used within the management of cancer in all stages are multiple biomedical imaging. Imaging as a very important part of cancer clinical protocols can offer a range of knowledge regarding morphology, structure, metabolism, and functions. Supported by relevant literature, this text provides an outline of the previous and new modalities employed in the sector of breast imaging. Any progress in technology can result in increased imaging speed to satisfy physiological processes necessities. One of the problems within the designation of breast cancer is sensitivity limitation. To overcome this limitation, complementary imaging examinations are used that historically include screening, ultrasound, MRI, etc.
Developing and Using Computational Frameworks to Conduct Numerical Analysis and Calculate Temperature Profiles and to Classify Breast Abnormalities
Authors: Queiroz Kamila Fernanda F. da C. , Araújo Marcus Costa de , Espíndola Nadja Accioly , Santos Ladjane C. , Santos Francisco G. S. , de Lima Rita de Cássia Fernandes
Published: July 2020

In this chapter, computational tools that have been designed to analyze and classify infrared (IR) images will be presented. The function of such tools is to interconnect in a user-friendly way the algorithms that are used to map temperatures and to classify some breast pathologies. One of these performs texture mapping using IR breast images to relate temperatures measured to the points over the substitute tridimensional geometry mesh. Another computer-aided diagnosis (CAD) tool was adapted so that it could be used to evaluate individual patients. This methodology will be used when the computational framework approach for classification is described. Finally, graphical interfaces and their functionalities will be presented and explained. Some case studies will be presented in order to verify whether or not the computational classification framework is effective.
Applications of the Use of Infrared Breast Images
Authors: Bezerra Luciete Alves , Melo João Roberto Ferreira de , Lyra Paulo Roberto Maciel , Lima Rita de Cássia Fernandes de
Published: July 2020

In this chapter, procedures for and applications of using infrared (IR) imaging that have been developed will be presented and proposed means by which a better detailed understanding of breast cancer can be reached. It will be shown how such applications can be used as a basis for enhancing the use of breast thermographic imaging as a user-friendly and inexpensive tool for the early detection of breast cancer. The authors intend to show that IR imaging can also be used to validate temperature profiles that have been calculated and to classify breast abnormalities as set out in previous chapters. IR images can also be used to estimate thermophysical properties of the breast, and discussion of how this is done is included. The IR images were acquired at the Outpatients Clinic of Mastology of the Hospital das Clínicas of the Federal University of Pernambuco (HC/UFPE). The research project was registered in the Brazilian Health Ministry (CEP/CCS/UFPE nº 279/05) after being approved by the Ethics Committee of UFPE.
The Efforts of Deep Learning Approaches for Breast Cancer Detection Based on X-Ray Images
Authors: Ismael Aras Masood , Gomes Juliana Carneiro
Published: July 2020

In this chapter, deep learning-based approaches, namely deep feature extraction, fine-tuning of pre-trained convolutional neural networks (CNN), and end-to-end training of a developed CNN model, are used to classify the malignant and normal breast X-ray images. For deep feature extraction, pre-trained deep CNN models such as ResNet18, ResNet50, ResNet101, VGG16, and VGG19 are used. For classification of the deep features, the support vector machines (SVM) classifier is used with various kernel functions namely linear, quadratic, cubic, and Gaussian, respectively. The aforementioned pre-trained deep CNN models are also used in fine-tuning procedure. A new CNN model is also proposed in end-to-end training fashion. The classification accuracy is used as performance measurements. The experimental works show that the deep learning has potential in detection of the breast cancer from the X-ray images. The deep features that are extracted from the ResNet50 model and SVM classifier with linear kernel function produced 94.7% accuracy score which the highest among all obtained.
Web 2.0, Social Media, and Mobile Technologies for Connected Government
Authors: Mahmood Zaigham
Published: July 2020

A connected government uses digital technologies for public administration to improve the democratic processes and provide electronic services to strengthen support for public policies. Also referred to as Government 2.0, it aims to harness the information revolution to improve the lives of citizens and enhance the efficiency of governmental processes. Some of the digital technologies and methods that advanced economies are already using to enhance the connected governance include mobile computing, internet of things, social media applications, and Web 2.0-related communication tools. Through the use of such technologies, governments and citizens can interact in real time, whereby citizens can voice their opinions and engage in the electronic participation. In this chapter, the author introduces Web 2.0, social media networking, and mobile technologies, and then, outlining the characteristics of a connected government, the chapter discusses how mobile, Web 2.0, and social networking tools can support governments to enhance transparency, openness, and effectiveness.
Citizen Data in Distributed Computing Environments
Authors: Soundarabai P Beaulah , Raj Pethuru , Mahmood Zaigham
Published: July 2020

Data security is paramount in the increasingly connected world. Securing data, while in transit and rest, and while under usage, is essential for deriving actionable insights out of data heaps. Incorrect or wrong data can lead to incorrect decisions. So, the confidentiality and integrity of data have to be guaranteed through a host of technology-inspired security solutions. Organizational data is kept confidentially by the businesses and governments, often in distant locations (e.g., in cloud environments), though more sensitive data is normally kept in house. As the security mechanisms are getting more sophisticated, cyber security attacks are also becoming more intensive, so there is a constant battle between the organisations and the hackers to be one step ahead of the other. In this chapter, the aim is to discuss various mechanisms of accomplishing citizens' data confidentiality and privacy and to present solution approaches for ensuring impenetrable security for personal data.
Effect of CeO2 Nanoparticle on the Structural and Electrical Properties of BSCCO-2223 High Temperature Superconductor
Authors: Nurbaisyatul E.S. , Azhan Hashim , Kasim Azman , Ibrahim Norazila
Published: July 2020

A study of the effects of Cerium oxide nanoparticle doped with BSCCO-2223 on the microstructure and superconducting properties was carried out. All samples were synthesized using solid state reaction method. Ce concentration is varied from x = 0.0 up to 0.1 in a general stoichiometry of Bi1.6Pb0.4Sr2Ca1-xCexCu3Oy. The samples were characterized structurally and electrically by X-Ray Diffraction (XRD) and four-point probe method respectively. XRD analysis shows that both (Bi,Pb)-2212 and (Bi,Pb)-2223 phases coexist in the samples having tetragonal crystal structure but changed to orthorhombic when x=0.10. The values of critical transition temperature, TC and critical current density, JC of the samples decreased with the increase in Ce concentration. The possible reasons for the observed degradation in superconducting and structural properties of Bi-2223 due to Ce nanoparticles addition were discussed.
Effect on Electrochemical Performance of Cr and Ni Substitution in LiCoO2 Cathode Materials
Authors: Mohd Abdillih Nor Syamilah Syamimi , Kamarulzaman Norlida , Elong Kelimah , Mastuli Mohd Sufri
Published: July 2020

The effect of Cr and Ni substitution on electrochemical performance of layered LiCo0.9M0.1O2 (M=Cr and Ni) has been investigated. Partial substituted of LiCo0.9Cr0.1O2 and LiCo0.9Ni0.1O2 has been synthesized using a self-propagating combustion (SPC) method with annealing temperature of 700 ̊ C for 24 h. The starting materials used were metal nitrates and citric acid act as a combustion agent. The phase and crystalinity of the materials were characterized using X-Ray Diffraction (XRD) and results showed that the single phase and pure materials were obtained with no impurity peaks were detected. The morphology and particle sizes of samples also analyzed using Field Emission Scanning Electron Microcopy (FESEM). The electrochemical performances of the materials were measured by its charge-discharge cycling which carried out in the voltage range of 2.5 V to 4.5 V. The results from charge-discharge studies found that LiCo0.9Ni0.1O2 has better specific discharge capacity compared with LiCo0.9Cr0.1O2.
Structural Studies and Ionic Transport Properties of Solid Biopolymer Electrolytes Based on Chitosan/ Methyl Cellulose Blend Doped with BMIMTFSI
Authors: Misenan M.S.M. , Khiar Azwani Sofia Ahmad
Published: July 2020

Fourier Transform Infrared (FT-IR), was applied to investigate the complexation, structural, ionic transport properties and dominant charge carrier species in Chitosan (CS) / Methyl Cellulose (MC) blend doped with 1 – butyl – 3 – methylimidazolium bis (trifluorosulfonyl) imide (BMIMTFSI) solid biopolymer electrolytes (SBEs) which have been prepared via solution casting technique. Samples were partially opaque in appearance with no phase separation. The occurrence of interactions between the host polymer CS/MC blend and ionic dopant BMIMTFSI were proven by FT-IR analysis from the shift in C-O band in 1049 cm-1. The FTIR spectrum in the region between 1080 and 980 cm−1 were deconvoluted using Origin 8 software to disclose the percentage of free mobile ions and contact ion of the samples. Ionic transport properties analysis reveals that the ionic conductivity is dependent on the ionic mobility (μ) and diffusion of ions (D).Keywords: Biopolymer Electrolyte; Polymer Blend; Chitosan, Methylcellulose; BMITFSI; Ion transport.
Scan Rates and the Disparities in the Electrochemical Double Layer Capacitor (EDLC) Performance
Authors: Sa'adu Lawal , Hashim@Ismail Mohd Azman
Published: July 2020

Three electrochemical double layer capacitor (EDLC) cells (Cell X, Y and Z) made from an electrode of 90 wt. % of the multiwalled commercial carbon nanotubes, 10 wt. % of poly (vinylidene fluoride-co-hexafluoropropylene) and three different samples of electrolytes polymer electrolyte made up of a compositions of 50:50, 60:40 and 70:30 wt.% of H3PO4/PVA (in ratio) soaked in a filter paper was characterized in this study. The aim is to ascertain the disparities in performances of the cells in relation to their respective scan rates. Cyclic voltammetry (CV) measurement of cells shows a high specific capacitance of 313 Fg−1 for the scan rates 10 mV was recorded from the cell with the highest composition H3PO4/PVA ratio (i.e. 70:30 wt.%). However, when the CV of the cell was measured with different scan rates, disparities in the performance occurred, as only 94 and 174 Fg−1 was recorded at the scan rates 100 and 50 mV respectively for cell-X. The result was not different when the two other cells (60:40 and 70:30 wt. % of H3PO4/PVA) were measured at the same scan rates.
The Effect of Calcination Time on Crystallite Size of LiMn1.8Ni0.2O4 Cathode Materials
Authors: Matius Michelle , Kamarulzaman Norlida , Mastuli Mohd Sufri , Abdillih Nor Syamilah Syamimi Mohd , Elong Kelimah
Published: July 2020

Spinel LiMn2O4 is one of the promising cathode materials used in commercial Li-ion batteries. In this study, Ni was partially substituted in order to give the material LiMn1.8Ni0.2O4, which was successfully synthesized using a self-propagating combustion (SPC) method. Results from Simultaneous Thermogravimetric Analysis (STA) show the small mass loss about 4.6%. The precursor then was calcined at temperature of 800 °C for 24 h, 48 h and 72 h. X-Ray Diffraction (XRD) confirms that the final products are pure and single phase with no impurities present. The morphology and crystallite size of pure samples are examined using Field Emission Scanning Electron Microscope (FESEM). The result shows that all the materials consist of crystalline particles with smooth surface and polyhedral shaped materials.
Phase Analysis of Cerate and Zirconate Ceramics Powder Prepared by Supercritical Ethanol Using High Temperature-High Pressure Batch Wise Reactor System
Authors: Osman Nafisah , Mazlan Nurul Waheeda , Hassan Oskar Hasdinor , Wan Zulkifli Wan Zuliana , Mohamed Zakiah
Published: July 2020

OAbstract. One of the approaches that has been done to produce a better performance of an intermediate temperature solid oxide fuel cell (IT-SOFC) is by varying the synthesis methods. This paper focused on the proton conducting electrolyte in particularly barium cerate and barium zirconate system namely BaCe0.9Y0.1O3-δ (BCY) and BaZr0.9Y0.1O3-δ (BZY). Supercritical ethanol processing technique is one of the alternative synthesis routes that able to produce ceramics powder at lower calcination temperature. The samples were synthesized in High-Pressure-High-Temperature (HP-HT) Batch Wise reactor system using ethanol as reaction medium. XRD was used to study the structure of both samples and all the data were refined using Rietveld refinement method by X’pert Highscore software. VESTA software is used to observe the crystal structure for both BCY and BZY samples. Both BCY and BZY have 98.16% and 96.55% purity after being calcined at 700°C and 1100°C, respectively. This study showed that BCY has orthorhombic structure with lattice parameter a=8.76Å, b=6.24Å and c=6.21Å and BZY exhibited cubic structure with a=b=c, and a=4.194Å. It was observed that BCY synthesized by supercritical fluid (SCF) method at reduced calcination temperature exhibited an acceptable value of lattice paramter as compared to other method that used higher processing temperature.
Optimization of Dye Extraction from Purple Cabbage and Cordyline Fruticosa in Dye-Sensitized Solar Cell
Authors: Rosli Ainfatin Kamila , Suhaimi Syahida , Hashim@Ismail Mohd Azman , Yatim Nadhrah Md , Hamid Najiha
Published: July 2020

Increasing populations of about 29.24 million people in Malaysia along with rapid improvement and development results in increasing of the energy usage demands [1]. It is estimated that primary sources of energy consumption in the world is 86.4 % from fossil fuels which consists of 36.0 % from petroleum, 27.4 % from coal, 23.0 % from natural gas [2]. However, fossil fuels energy sources are non-renewable and also contribute to pollution. In order to fulfill the needs of energy used, solar light is expected to become a leading next-generation for clean and sustainable energy resources. The main interest of solar energy over other energy sources is that sunlight can be directly harvested into solar energy with the use of small and tiny photovoltaic (PV) solar cells [3].
Temperature and Salinity Effects on Photocatalytic Performance of Cerium Doped Zinc Oxide
Authors: Abdullah Wan Rafizah Wan , Siang Lee Chia , Rooshde Maishara Syazrinni , Ghazali Mohd Sabri Mohd
Published: July 2020

Cerium (Ce) doped ZnO is a promising material for advanced photocatalysis. It is useful for inducing the treatment of many organic pollutants in water. However, the stability of its performance under varying temperature and saline condition has never been not fully assessed. In this study, powder form photocatalyst comprising 99.0 mol% ZnO and 1 mol% CeO2 has been synthesized via modified citrate gelation technique and solid-state sintering at 1200 °C for 5 hours. The conversion of Ce doped ZnO from its precursors has been confirmed using XRD, SEM, and EDX techniques. The photocatalytic efficiency of the synthesized Ce doped ZnO under UV-C light (λ=265 nm) was determined. In the experiment, the operating temperature was varied between 25 to 40 °C, and the salinity of the treated solution was increased from 0 to 40 g/L NaCl. The findings revealed that the photocatalytic efficiency of Ce doped ZnO under UV light improved from 78.2% to 88.6% as the temperature increased from 25 to 40 °C. The performance of Ce doped ZnO decreased from 86.7% to 36.7% when the salinity increased from 0 g/L to 40 g/L. The elevation of temperature encouraged the photogeneration of electron-hole pairs on catalyst surface while the presence of chloride ions in treated medium caused scavenging of hydroxyl radicals or hole.
Determination of Cadmium Ions Using Schiff-Base Modified Carbon Paste Electrode: A Box-Behnken Design Approach
Authors: binti Azhari Azzusyaza , Wahab Roswanira Abdul , Ahamad Rahmalan
Published: July 2020

Being one of the hazardous contaminants in the environment, continuous exposure to cadmium ions (Cd (II)) has been shown to severely affect the well being of both humans and animals. Therefore, development of a highly sensitive method to detect trace amounts of such substance in the environment acquires scientific pertinence. In this present work, carbon paste electrode modified with bis (benzylidene) ethelynediamine (BBE-CPE) was used for the determination of Cd (II) using square wave anodic stripping voltammetric (SWASV) technique. A response surface methodological approach employing the Box-Behnken design (BBD) based on four relevant variables; pH, deposition time, percentage ligand and deposition potential was used for optimizing the experimental conditions for detecting such ions. Under optimized conditions (supporting electrolyte: pH 4.5, deposition time: 350 s, ligand graphite composition: 6%, deposition potential: ‒1.1 V), a linear response over a wide range of Cd (II) concentrations (1–500 μg L−1) with low detection limit (0.4 μg L-1) and quantification limit (1.4 μg L-1) were observed with deposition time being the most impacting factor. Pertinently, the BBE-CPE developed here exhibited exceptional recovery of Cd (II) concentrations in the sea and tap water samples, comparable with that observed under simulated conditions, suggesting its applicability for a variety of real samples.
Corrosion Inhibition Properties of Epoxy-Zinc Oxide Nanocomposite Coating on Stainless Steel 316L
Authors: Ibrahim Noradhiha Farahin , Wan Abdullah Wan Rafizah , Rooshde Maishara Syazrinni , Mohd Ghazali Mohd Sabri , Wan Nik Wan B.
Published: July 2020

Metal corrosion generally refers to metal deterioration process that is caused by electrochemical reactions between the metallic substrate with corrosive environment. Marine grade stainless steel type 316L (SS 316L) is a premium material for marine applications. Prolonged exposure to chloride-containing environments increases the susceptibility of unprotected SS 316L to localized corrosion namely pitting and crevice corrosion. In this study, the potential protective coating comprising of the epoxy matrix with ZnO nanoparticles combination was formulated and its anticorrosive properties on SS 316L substrate were analyzed. Variation in corrosion behaviour of SS 316L coated with a series of epoxy coating solution containing 1, 3, 5, 7 and 10 wt % ZnO nanoparticles were thoroughly observed. The coating formulations were characterised by using X-ray Diffraction (XRD) spectroscopy and Scanning Electron Microscope (SEM). Meanwhile, the corrosion performance testing was measured by using Potentiodynamic Polarization (PP) technique. The results revealed that epoxy coating incorporated with 3 wt % of ZnO nanoparticles provided the best corrosion protection on SS 316L as the corrosion rate for the metal substrate has been minimized from 0.05268 mm/year to as low as 0.00047 mm/year after coating. Dispersion of ZnO nanoparticles in epoxy matrix increases the barrier properties of the coating and impeded corrosion process on SS 316L through suppression of anodic reaction.
Physical, Absorption and Photoluminescence Performance of Eu3+ Doped Lithium Chloride Tellurite Glass
Authors: Yaacob Syariffah Nurathirah Syed , Sahar M.R. , Jupri Siti Aishah , Sazali E.S. , Zainal Roslinda , Marwoto Putut
Published: July 2020

A series of (74.4-x) TeO2 – (4.3) LiO2 – (21.3) LiCl – (x) Eu2O3 with 0.0 ≤ x ≤ 2.0 mol % has been made using melt-quenching technique and their optical characteristic has been studied. The present works cover the preparation of the glass sample and the effects of Eu3+ on the physical properties, absorption and photoluminescence behaviour of the lithium chloride tellurite glass. The physical properties such as density and molar volume are determined. It is found that the density and molar volume presents fluctuation trends. As the samples are excited at 393 nm, six emission peaks have been observed at 532, 552, 586, 613, 649, and 697 nm indicating the transitions of 5D1 → 7F1, 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 respectively. It is observed that transition 5D0 → 7F2 shows the highest intensity. The emission intensity increases with the increment of Eu2O3 concentration. The high-intensity ratios of 1.88 observed for glass sample contain 2.0 mol % Eu2O3 concentrations indicate a greater degree of Eu-O-covalency and possess the better quality of host matrix.
Effect of Blast Wave on Intermetallics Formation, Hardness and Reduced Modulus Properties of Solder Joints
Authors: Safee Nur Shafiqa , Wan Yusoff Wan Yusmawati , Ismail Ariffin , Ismail Norliza , Abu Bakar Maria , Jalar Azman
Published: July 2020

Tin-Silver-Copper (SnAgCu) lead-free solder on Electroless Nickel Immersion Gold (ENiG) and Immersion Tin (ImSn) surface finish printed circuit board was subjected to blast test. A variation of intermetallic compounds (IMC) layer, hardness and reduced modulus of soldered sample exposed to blast test were intensively investigated using optical microscope and nanoindentation machine. Formation of IMCs due to reaction between solder and substrate during blast test provided deleterious effect of metallurgical bond strength and reliability on the solder joint. Microstructural analysis was evaluated via Infinite Focused Microscope (IFM). The findings of these studies indicate that best surface finished for blast test performance was not necessarily the best surface finish for optimum reliability. ENiG and ImSn surface finish can be advantage or a disadvantage depending on the application, package and reliability requirements. As a result, most component assemblers are using ENiG and ImSn in order to improve solderability as well as the wettability between solder and the substrate and to meet various package requirements.
Effect of Temperature and Frequency on the Acoustic Properties of Konjac Glucomannan-Agar Gels as Tissue Mimicking Materials
Authors: Mat Daud Anis Nazihah , Rohani Md Supar , Jaafar Rosly
Published: July 2020

In this study, we determine the effect of temperature and frequency on the acoustic properties of konjac glucomannan (KGM)-agar gels to confirm their compatibilities as tissue mimicking materials (TMMs). The acoustic properties of four samples; A (KGM-0.10 g agar), B (KGM-0.20 g agar), C (KGM-0.30 g agar) and D (KGM-0.40 g agar) were measured using pulse echo immersion technique. Findings indicated that the longitudinal velocities of all samples were increased while their attenuation coefficients were decreased as the temperature increased from 27.0 to 37.0°C. It also showed that the phase velocities of all samples were independent to frequency but their attenuation coefficients were increased as the frequency increased from 4.0 to 6.0 MHz. KGM-agar gels are compatible as soft TMMs since their acoustic properties are comparable with the acoustic properties of soft tissue.
Graphene Based Macrobend Unclad SMF for Monitoring pH Level in Aqueous Environment
Authors: Mukhtar Wan Maisarah , Latib Siti Nadiah , Halim Razman Mohd , Rashid Affa Rozana Abdul
Published: July 2020

Partial unclad fibers with diameters ranging from d=121μm to d=125μm were fabricated using standard telecommunications optical fiber (SMF28) via low cost mechanical swipe-off technique. Graphene oxide (GO) was deposited using drop casting method on the outer side of the partial unclad SMF. IR laser with excitation wavelengths of λ=1310nm and λ=1550nm were launched along the graphene-coated SMF. The sensitivity of graphene based macrobend unclad SMFs were investigated by introducing two different pH of aqueous environment with values of 3.5 (acidic) and 12.5 (alkaline) that acted as sensing media. The optimum power loss was obtained as smallest diameter of partial unclad SMF with d=121μm was appointed. As uncoated SMF was replaced with the GO coated SMF which had been immersed into 3.5pH liquid solution, it was found that the optical power losses were increased about 6.79dBm and 5.15dBm using laser with λ1=1310nm and λ2=1550nm respectively. The uncoated SMFs experienced the increment of power losses about 2.11dBm and 5.15dBm as they were soaked into the solution with pH=12.5 using similar laser of λ1 and λ2. It is noteworthy to highlight the significant of graphene’s employment on macrobend unclad SMF by using λ1=1310nm in which better sensitivity and selectivity represented by maximum changes of power losses were apparently observed for both solutions. The usage of λ=1550nm exhibited poor selectivity where the partial unclad SMF unable to differentiate two contrasting pH solution. In conclusion, graphene based macrobend fiber optic sensor for pH detection was successfully developed by employing partial unclad SMF with cladding diameter of d=121μm and laser wavelength of λ=1310nm due to the enhancement of evanescent field’s strength.