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2019

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Technical Analysis, Paula Bourke Jan 2019

Technical Analysis, Paula Bourke

Datasets

Transcription analysis was performed for Listeria monocytogenes EGD-e wild type strain. Relative expression of stress associated genes (prfA, sigB, rsbR, gadD, lmo0799) following exposure to ACP treatment was quantified using real-time reverse transcription-PCR (RT-PCR).

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English Wikipedia Corpus Chunks, Filip Klubicka, Alfredo Maldonado, Abhijit Mahalunkar, John D. Kelleher Jan 2019

English Wikipedia Corpus Chunks, Filip Klubicka, Alfredo Maldonado, Abhijit Mahalunkar, John D. Kelleher

Datasets

This archive contains a collection of language corpora. These are text files that contain samples of text collected from English Wikipedia.

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A U-Net Deep Learning Framework For High Performance Vessel Segmentation In Patients With Cerebrovascular Disease, Michelle Livne, Jana Rieger, Orhun Utku Aydin, Abdel Aziz Taha, Ela Marie Akay, Tabea Kossen, Jan Sobesky, John D. Kelleher, Kristian Hildebrand, Dietmar Frey, Vince I. Madai Jan 2019

A U-Net Deep Learning Framework For High Performance Vessel Segmentation In Patients With Cerebrovascular Disease, Michelle Livne, Jana Rieger, Orhun Utku Aydin, Abdel Aziz Taha, Ela Marie Akay, Tabea Kossen, Jan Sobesky, John D. Kelleher, Kristian Hildebrand, Dietmar Frey, Vince I. Madai

Articles

Brain vessel status is a promising biomarker for better prevention and treatment in cerebrovascular disease. However, classic rule-based vessel segmentation algorithms need to be hand-crafted and are insufficiently validated. A specialized deep learning method—the U-net—is a promising alternative. Using labeled data from 66 patients with cerebrovascular disease, the U-net framework was optimized and evaluated with three metrics: Dice coefficient, 95% Hausdorff distance (95HD) and average Hausdorff distance (AVD). The model performance was compared with the traditional segmentation method of graph-cuts. Training and reconstruction was performed using 2D patches. A full and a reduced architecture with less parameters were trained. We …

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Capturing And Measuring Thematic Relatedness, Magdalena Kacmajor, John D. Kelleher Jan 2019

Capturing And Measuring Thematic Relatedness, Magdalena Kacmajor, John D. Kelleher

Articles

In this paper we explain the difference between two aspects of semantic relatedness: taxonomic and thematic relations. We notice the lack of evaluation tools for measuring thematic relatedness, identify two datasets that can be recommended as thematic benchmarks, and verify them experimentally. In further experiments, we use these datasets to perform a comprehensive analysis of the performance of an extensive sample of computational models of semantic relatedness, classified according to the sources of information they exploit. We report models that are best at each of the two dimensions of semantic relatedness and those that achieve a good balance between the …

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Large-Scale Green Supplier Selection Approach Under A Q-Rung Interval-Valued Orthopair Fuzzy Environment, Limei Liu, Wenzhi Cao, Biao Shi, Ming Tang Jan 2019

Large-Scale Green Supplier Selection Approach Under A Q-Rung Interval-Valued Orthopair Fuzzy Environment, Limei Liu, Wenzhi Cao, Biao Shi, Ming Tang

Articles

As enterprises pay more and more attention to environmental issues, the green supply chain management (GSCM) mode has been extensively utilized to guarantee profit and sustainable development. Greensupplierselection(GSS),whichisakeysegmentofGSCM,hasbeeninvestigated to put forward plenty of GSS approaches.

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The "Invisible Hand" Of Peer Review: The Implications Of Author-Referee Networks On Peer Review In A Scholarly Journal, Pierpaolo Dondio, Niccolo Casnici, Nigel Gilbert, Francisco Grimaldo, Flaminio Squazzoni Jan 2019

The "Invisible Hand" Of Peer Review: The Implications Of Author-Referee Networks On Peer Review In A Scholarly Journal, Pierpaolo Dondio, Niccolo Casnici, Nigel Gilbert, Francisco Grimaldo, Flaminio Squazzoni

Articles

Peer review is not only a quality screening mechanism for scholarly journals. It also connects authors and referees either directly or indirectly. This means that their positions in the network structure of the community could influence the process, while peer review could in turn influence subsequent networking and collaboration. This paper aims to map these complex network implications by looking at 2232 author/referee couples in an interdisciplinary journal that uses double blind peer review. By reconstructing temporal co-authorship networks, we found that referees tended to recommend more positively submissions by authors who were within three steps in their collaboration network. …

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Adaptive Heuristics That (Could) Fit: Information Search And Communication Patterns In An Online Forum Of Investors Under Market Uncertainty, Niccolo Casnici, Marco Castellani, Flaminio Squazzoni, Manuela Testa, Pierpaolo Dondio Jan 2019

Adaptive Heuristics That (Could) Fit: Information Search And Communication Patterns In An Online Forum Of Investors Under Market Uncertainty, Niccolo Casnici, Marco Castellani, Flaminio Squazzoni, Manuela Testa, Pierpaolo Dondio

Articles

This article examines information-search heuristics and communication patterns in an online forum of investors during a period of market uncertainty. Global connections, real-time communication, and technological sophistication have created an unpredictable market environment. As such, investors try to deal with semantic, strategic, and operational uncertainty by following heuristics that reduce information redundancy. In this study, we have tried to find traces of cognitive communication heuristics in a large-scale data set including 8 years of online posts (2004–2012) for a forum of Italian investors. We identified various market volatility conditions on a daily basis to understand the influence of market uncertainty …

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Direct Instruction And Its Extension With A Community Of Inquiry: A Comparison Of Mental Workload, Performance And Efficiency, Giuliano Orru, Luca Longo Jan 2019

Direct Instruction And Its Extension With A Community Of Inquiry: A Comparison Of Mental Workload, Performance And Efficiency, Giuliano Orru, Luca Longo

Articles

This paper investigates the efficiency of two instructional design conditions: a traditional design based on the direct instruction approach to learning and its extension with a collaborative activity based upon the community of inquiry approach to learning. This activity was built upon a set of textual trigger questions to elicit cognitive abilities and support knowledge formation. A total of 115 students participated in the experiments and a number of third-level computer science classes where divided in two groups. A control group of learners received the former instructional design while an experimental group also received the latter design. Subsequently, learners of …

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Multi-Spectral Visual Crop Assessment Under Limited Data Constraints, Patricia O'Byrne, Patrick Jackman, Damon Berry, Hector-Hugo Franco-Penya, Michael French, Robert J. Ross Jan 2019

Multi-Spectral Visual Crop Assessment Under Limited Data Constraints, Patricia O'Byrne, Patrick Jackman, Damon Berry, Hector-Hugo Franco-Penya, Michael French, Robert J. Ross

Conference papers

In an era of climate change and global population growth, deep learning based multi-spectral imaging has the potential to significantly assist in production management across a wide range of agricultural and food production domains. A key challenge however in applying state-of-the-art methods is that they, unlike classical hand crafted methods, are usually thought of as being only useful when significant amounts of data are available. In this paper we investigate this hypothesis by examining the performance of state-of-the-art deep learning methods when applied to a restricted data set that is not easily bootstrapped through pre-trained image processing networks. We demonstrate …

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Cytotoxic And Genotoxic Action Of Tagetes Patula Flower Methanol Extract And Patuletin Using The Allium Test, Mudassar Azhar, Ahsana Dar Farooq, Sayedul Haque, Samina Bano, Lubna Zaheer, Shaheen Faizi Jan 2019

Cytotoxic And Genotoxic Action Of Tagetes Patula Flower Methanol Extract And Patuletin Using The Allium Test, Mudassar Azhar, Ahsana Dar Farooq, Sayedul Haque, Samina Bano, Lubna Zaheer, Shaheen Faizi

Turkish Journal of Biology

Tagetes patula is used to treat cancer patients in alternative healthcare systems. However, its cytotoxic and genotoxic effects have not been reported. Therefore, the methanol extract of T. patula flower, the ethyl acetate fraction, and the pure compound patuletin were evaluated using the Allium test. The methanol extract and fraction contained ~3% and ~36% patuletin, respectively, with ~98% purity. The methanol extract caused inhibition of Allium root growth displaying an IC50 value of ~500 μg/mL, while the fraction and patuletin were more potent by ~2 and ~5 times, respectively. The Allium root tips demonstrated a decline in prophase, metaphase, anaphase, …

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The Nlrp3 Inflammasome: A New Player In Neurological Diseases, Eli̇f Eren, Nesri̇n Özören Jan 2019

The Nlrp3 Inflammasome: A New Player In Neurological Diseases, Eli̇f Eren, Nesri̇n Özören

Turkish Journal of Biology

Inflammasomes are supramolecular protein complexes implicated in the detection of pathogens or danger-associated molecules and are responsible for mounting the first line of innate immune response to counteract these signals and restore tissue homeostasis. Among different inflammasomes identified so far, NLRP3 is of main interest since mutations in Nlrp3 gene are associated with autoinflammatory diseases such as Muckle-Wells syndrome, neonatal onset multisystem inflammatory disease, and familial cold urticaria/autoinflammatory syndrome. On the other hand, whereas other inflammasomes are mainly detectors of specific molecular motifs, NLRP3 is acting as a general sensor of cellular perturbations including potassium efflux, lysosomal damage, and ROS …

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Identification Of Watermelon Heat Shock Protein Members And Tissue-Specific Gene Expression Analysis Under Combined Drought And Heat Stresses, Yasemi̇n Çeli̇k Altunoğlu, Merve Keleş, Tevfi̇k Hasan Can, Mehmet Cengi̇z Baloğlu Jan 2019

Identification Of Watermelon Heat Shock Protein Members And Tissue-Specific Gene Expression Analysis Under Combined Drought And Heat Stresses, Yasemi̇n Çeli̇k Altunoğlu, Merve Keleş, Tevfi̇k Hasan Can, Mehmet Cengi̇z Baloğlu

Turkish Journal of Biology

Heat shock protein (Hsp) gene family members in the watermelon genome were identified and characterized by bioinformatics analysis. In addition, expression profiles of genes under combined drought and heat stress conditions were experimentally analyzed. In the watermelon genome, 39 genes belonging to the sHsp family, 101 genes belonging to the Hsp40 family, 23 genes belonging to the Hsp60 family, 12 genes belonging to the Hsp70 family, 6 genes belonging to the Hsp90 family, and 102 genes belonging to the Hsp100 family were found. It was also observed that the proteins in the same cluster in the phylogenetic trees had similar …

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Explorobot: Rapid Exploration With Chart Automation, Tamara Matthews, Rohan Goel, John Mcauley Jan 2019

Explorobot: Rapid Exploration With Chart Automation, Tamara Matthews, Rohan Goel, John Mcauley

Conference papers

General-purpose visualization tools are used by people with varying degrees of data literacy. Often the user is not a professional analyst or data scientist and uses the tool infrequently, to support an aspect of their job. This can present difficulties as the user’s unfamiliarity with visualization practice and infrequent use of the tool can result in long processing time, inaccurate data representations or inappropriate visual encodings. To address this problem, we developed a visual analytics application called exploroBOT. The exploroBOT automatically generates visualizations and the exploration guidance path (an associated network of decision points, mapping nodes where visualizations change). These …

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Mediaeval2019: Flood Detection In Time Sequence Satellite Images, Palavi Jain, Bianca Schoen-Phelan, Robert J. Ross Jan 2019

Mediaeval2019: Flood Detection In Time Sequence Satellite Images, Palavi Jain, Bianca Schoen-Phelan, Robert J. Ross

Conference papers

In this work, we present a flood detection technique from time series satellite images for the City-centered satellite sequences (CCSS) task in the MediaEval 2019 competition [1]. This work utilises a three channel feature indexing technique [13] along with a VGG16 pretrained model for automatic detection of floods. We also compared our result with RGB images and a modified NDWI technique by Mishra et al, 2015 [15]. The result shows that the three channel feature indexing technique performed the best with VGG16 and is a promising approach to detect floods from time series satellite images.

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On The Inability Of Markov Models To Capture Criticality In Human Mobility, Vaibhav Klukarni, Abhijit Mahalunkar, Benoit Garbinato, John Kelleher Jan 2019

On The Inability Of Markov Models To Capture Criticality In Human Mobility, Vaibhav Klukarni, Abhijit Mahalunkar, Benoit Garbinato, John Kelleher

Conference papers

We examine the non-Markovian nature of human mobility by exposing the inability of Markov models to capture criticality in human mobility. In particular, the assumed Markovian nature of mobility was used to establish an upper bound on the predictability of human mobility, based on the temporal entropy. Since its inception, this bound has been widely used for validating the performance of mobility prediction models. We show that the variants of recurrent neural network architectures can achieve significantly higher prediction accuracy surpassing this upper bound. The central objective of our work is to show that human-mobility dynamics exhibit criticality characteristics which …

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A Self Healing Microservices Architecture: A Case Study In Docker Swarm Cluster, Basel Magableh, Muder Almiani Jan 2019

A Self Healing Microservices Architecture: A Case Study In Docker Swarm Cluster, Basel Magableh, Muder Almiani

Conference papers

One desired aspect of a self-adapting microservices architecture is the ability to continuously monitor the operational environment, detect and observe anomalous behaviour as well as implement a reasonable policy for self-scaling, self-healing, and self-tuning the computational resources in order to dynamically respond to a sudden change in its operational environment. Often the behaviour of a microservices architecture continuously changes over time and the identification of both normal and abnormal behaviours of running services becomes a challenging task. This paper proposes a self-healing Microservice architecture that continuously monitors the operational environment, detects and observes anomalous behaviours, and provides a reasonable adaptation …

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Agent-Based Iot Coordination For Smart Cities Considering Security And Privacy, Iván García-Magariño, Geraldine Gray, Rajarajan Muttukrishnan, Waqar Asif Jan 2019

Agent-Based Iot Coordination For Smart Cities Considering Security And Privacy, Iván García-Magariño, Geraldine Gray, Rajarajan Muttukrishnan, Waqar Asif

Conference papers

The interest in Internet of Things (IoT) is increasing steeply, and the use of their smart objects and their composite services may become widespread in the next few years increasing the number of smart cities. This technology can benefit from scalable solutions that integrate composite services of multiple-purpose smart objects for the upcoming large-scale use of integrated services in IoT. This work proposes an agent-based approach for supporting large-scale use of IoT for providing complex integrated services. Its novelty relies in the use of distributed blackboards for implicit communications, decentralizing the storage and management of the blackboard information in the …

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An Evaluation Of The Reliability, Validity And Sensitivity Of Three Human Mental Workload Measures Under Different Instructional Conditions In Third-Level Education, Luca Longo, Giuliano Orru Jan 2019

An Evaluation Of The Reliability, Validity And Sensitivity Of Three Human Mental Workload Measures Under Different Instructional Conditions In Third-Level Education, Luca Longo, Giuliano Orru

Conference papers

Although Cognitive Load Theory (CLT) has been researched for many years, it has been criticised for its theoretical clarity and its methodological approach. A crucial issue is the measurement of three types of cognitive load conceived in the theory, and the assessment of overall human cognitive load during learning tasks. This research study is motivated by these issues and it aims to investigate the reliability, validity and sensitivity of three existing self-reporting mental workload instruments, mainly used in Ergonomics, when applied to Education and in particular to the field of Teaching and Learning. A primary research study has been designed …

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The Evolution Of Cognitive Load Theory And The Measurement Of Its Intrinsic, Extraneous And Germane Loads: A Review, Giuliana Orru, Luca Longo Jan 2019

The Evolution Of Cognitive Load Theory And The Measurement Of Its Intrinsic, Extraneous And Germane Loads: A Review, Giuliana Orru, Luca Longo

Conference papers

Cognitive Load Theory has been conceived for supporting instructional design through the use of the construct of cognitive load. This is believed to be built upon three types of load: intrinsic, extraneous and germane. Although Cognitive Load Theory and its assumptions are clear and well-known, its three types of load have been going through a continuous investigation and re-definition. Additionally, it is still not clear whether these are independent and can be added to each other towards an overall measure of load. The purpose of this research is to inform the reader about the theoretical evolution of Cognitive Load Theory …

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Fuzzy-Gra Trust Model For Cloud Risk Management, Abdul Razaque, Muder Almiani, Meer Jaro Khan, Basel Magableh, Ayman Al-Dmour, Amer Al-Rahayfeh Jan 2019

Fuzzy-Gra Trust Model For Cloud Risk Management, Abdul Razaque, Muder Almiani, Meer Jaro Khan, Basel Magableh, Ayman Al-Dmour, Amer Al-Rahayfeh

Conference papers

Cloud computing is not adequately secure due to the currently used traditional trust methods such as global trust model and local trust model. These are prone to security vulnerabilities. This paper introduces a trust model based on the fuzzy mathematics and gray relational theory. Fuzzy mathematics and gray relational analysis (Fuzzy-GRA) aims to improve the poor dynamic adaptability of cloud computing. Fuzzy-GRA platform is used to test and validate the behavior of the model. Furthermore, our proposed model is compared to other known models. Based on the experimental results, we prove that our model has the edge over other existing …

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The Political Power Of Twitter, James Usher, Pierpaolo Dondio, Lucia Morales Jan 2019

The Political Power Of Twitter, James Usher, Pierpaolo Dondio, Lucia Morales

Conference papers

In June 2016, the British voted by 52 per cent to leave the EU, a club the UK joined in 1973. This paper examines Twitter public and political party discourse surrounding the BREXIT withdrawal agreement. In particular, we focus on tweets from four different BREXIT exit strategies known as “Norway”, “Article 50”, the “Backstop” and “No Deal” and their effect on the pound and FTSE 100 index from the period of December 10th 2018 to February 24th 2019. Our approach focuses on using a Naive Bayes classification algorithm to assess political party and public Twitter sentiment. A Granger causality analysis …

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Brexit: A Granger Causality Of Twitter Political Polarisation On The Ftse 100 Index And The Pound, James Usher, Lucia Morales, Pierpaolo Dondio Jan 2019

Brexit: A Granger Causality Of Twitter Political Polarisation On The Ftse 100 Index And The Pound, James Usher, Lucia Morales, Pierpaolo Dondio

Conference papers

BREXIT is the single biggest geopolitical event in British history since WWII. Whilst the political fallout has become a tragicomedy, the political ramifications has had a profound impact on the Pound and the FTSE 100 index. This paper examines Twitter political discourse surrounding the BREXIT withdrawal agreement. In particular we focus on the discussions around four different exit strategies known as “Norway”, “Article 50”, the“Backstop” and “No Deal” and their effect on the pound and FTSE 100 index from the period of rumblings of the cancellation of the Meaning Vote on December 10th 2018 inclusive of second defeat on the …

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Taxonomic Word Embeddings - Trained On English Wordnet Random Walk Pseudo-Corpora, Filip Klubicka, Alfredo Maldonado, Abhijit Mahalunkar, John D. Kelleher Jan 2019

Taxonomic Word Embeddings - Trained On English Wordnet Random Walk Pseudo-Corpora, Filip Klubicka, Alfredo Maldonado, Abhijit Mahalunkar, John D. Kelleher

Datasets

This archive contains a collection of computational models called word embeddings. These are vectors that contain numerical representations of words. They have been trained on pseudo-sentences generated artificially from a random walk over the English WordNet taxonomy, and thus reflect taxonomic knowledge about words (rather than contextual).

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The Protective Effect Of N-Acetylcysteine Amide Against Paraquat-Induced Neurotoxicity, Burhan Ateş, Ni̇gar Vardi, Hakan Parlakpinar, Merve Gökşi̇n Karaaslan, İsmet Yilmaz, Nuran Ercal Jan 2019

The Protective Effect Of N-Acetylcysteine Amide Against Paraquat-Induced Neurotoxicity, Burhan Ateş, Ni̇gar Vardi, Hakan Parlakpinar, Merve Gökşi̇n Karaaslan, İsmet Yilmaz, Nuran Ercal

Turkish Journal of Chemistry

N-acetylcysteine amide (NACA) is a new antioxidant molecule with powerful radical scavenging properties. The aim of this study was to investigate neuroprotective effects of NACA against paraquat (PQ) toxicity in the midbrains of rats by using motor coordination tests and biochemical and histological analysis. Thirty adult Wistar albino rats were divided into three groups: Group 1: control (n = 10), Group 2: PQ (10 mg/kg) (n = 10), and Group 3: PQ (10 mg/kg) $+$ NACA (100 mg/kg) (n = 10). NACA was administrated intraperitoneally 30 min before PQ injection. Performance was measured for a period of 28 days. The …

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An Evaluation Of The Adsorption Dynamics Of Phosphate Ions Onto Fe(Ii)-Montmorillonites, Dawei Qin, Shuhua Chang, Min Qiao, Xiaotong Yuan, Wei Liu, Gang Liu Jan 2019

An Evaluation Of The Adsorption Dynamics Of Phosphate Ions Onto Fe(Ii)-Montmorillonites, Dawei Qin, Shuhua Chang, Min Qiao, Xiaotong Yuan, Wei Liu, Gang Liu

Turkish Journal of Chemistry

Fe(II)-montmorillonites (Fe(II)-MMTs) were prepared by mixing solutions of Fe(II) and montmorillonite at pH 3.5. Two different Fe(II)-MMTs were prepared and the ferrous iron contents were 40 mg/L and 80 mg/L. All samples were characterized by XRD, FT-IR, TGA, DSC, and nitrogen adsorption. By nitrogen adsorption, the pore size can be obtained in the pore diameter curve with average pore widths of 6.67 nm, 9.96 nm, and 17.07 nm, respectively. The removal rate of phosphate increased rapidly during the first 40 min, in which Fe(II)-MMT (1) and Fe(II)-MMT (2) were stronger adsorption systems than MMT. The maximum adsorption was 48.38 mg/g …

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Electrodeposition Of Tin(Ii) From Citrate Complexes, Yuliya Yapontseva, Valeriy Kublanovsky Jan 2019

Electrodeposition Of Tin(Ii) From Citrate Complexes, Yuliya Yapontseva, Valeriy Kublanovsky

Turkish Journal of Chemistry

This paper provides the calculation of the distribution of the concentrations of complex particles of the Sn(II) - citrate - water system in the solution volume, on the surface of the electrode, and in the diffusion layer for the tin citrate electrolyte containing an excess of the ligand. Based on the calculations for the electrodeposition of tin, an electrolyte containing [SnCit]$^{2-}$ complex at pH 8.0 was chosen. The kinetic parameters of the discharge stage, the diffusion coefficient of the electrochemical active ion, and the current efficiency of tin were determined by the methods of stationary voltammetry and chronovoltamperometry. It is …

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Preparation And Physicochemical Characterization Of Zinc Oxide/Sodium Cellulose Composite For Food Packaging, Sherif Mohamed Abdel Salam Keshk, Mohamed Saad Hamdy Jan 2019

Preparation And Physicochemical Characterization Of Zinc Oxide/Sodium Cellulose Composite For Food Packaging, Sherif Mohamed Abdel Salam Keshk, Mohamed Saad Hamdy

Turkish Journal of Chemistry

Zinc oxide/sodium cellulose composite with different ZnO loadings was prepared for the first time. The crystal structures of cellulose, sodium cellulose, and ZnO/sodium cellulose composite were characterized by FT-IR, XRD, XPS, SEM, and EDX. ZnO/sodium cellulose showed a similar XRD pattern to that of cellulose II. The XPS spectrum emphasized the presence of Zn$^{2+}$ and Na$^{+\, }$ ions in the prepared composite. Additionally, the SEM analysis showed the growth of ZnO crystals on the sodium cellulose surface. UV-Vis spectrometry of the ZnO/sodium cellulose spectrum showed a distinguished absorption band at 360 nm that was attributed to the presence of ZnO …

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Efficient Synthesis And Antifungal Investigation Of Nucleosides' Quaternary Ammonium Salt Derivatives, Barbara Dmochowska, Lucyna Pellowska-Januszek, Justyna Samaszko-Fiertek, Rafal Slusarz, Roland Wakiec, Janusz Madaj Jan 2019

Efficient Synthesis And Antifungal Investigation Of Nucleosides' Quaternary Ammonium Salt Derivatives, Barbara Dmochowska, Lucyna Pellowska-Januszek, Justyna Samaszko-Fiertek, Rafal Slusarz, Roland Wakiec, Janusz Madaj

Turkish Journal of Chemistry

Quaternary ammonium salts are a group of compounds with diverse biological properties, the most important of which are their antiviral, antibacterial, and antifungal activities. The quaternization reactions of 5'-$O$-tosyl derivatives of uridine and thymidine with triethylamine, trimethylamine, 4-($N$,$N$-dimethylamino)pyridine, 2-methylpyridine, and pyridine are described in this article. Two of the synthesized compounds are exceptional because they are first of this type that demonstrate concentration-dependent antifungal in vitro activity against two species of the genus Candida in minimal YNB-SG medium. The experimental results have been extended by adding full atom molecular dynamics simulations and substrates and products energies evaluation.

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In Situ Preparation Of Hydroxyapatite Composites Into Hydrolyzed Polyacrylamide Solution And Methylene Blue Dye Retention, Ali Mansri, Hanane Mahroug, Faycal Dergal Jan 2019

In Situ Preparation Of Hydroxyapatite Composites Into Hydrolyzed Polyacrylamide Solution And Methylene Blue Dye Retention, Ali Mansri, Hanane Mahroug, Faycal Dergal

Turkish Journal of Chemistry

Four composites of hydroxyapatite/hydrolyzed polyacrylamide (HAP/HPAM-n) were prepared using an in situ wet chemical method. The synthesis was performed by preparing a suspension of calcium in a copolymer solution having a known HPAM concentration. Phosphoric acid was added dropwise to each suspension to obtain HAP/HPAM-n composites. The effect of initial copolymer amount on the composite properties was investigated using XRD, FTIR, TGA, and SEM/EDS analysis. The obtained results were compared to the HAP sample synthesized under the same conditions and without copolymer. HPAM amount in the composite affects the retention of methylene blue (MB) dye. The result shows that the …

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Rapid And On-Site Electrochemical Detection Of Bisphenol A And Arsenic In Drinking Water Using A Novel Electrode Array, Yildiz Uludağ, Zehra Ölçer, Canan Doğan, Turghun Muhammad, Zeynep Altintaş Jan 2019

Rapid And On-Site Electrochemical Detection Of Bisphenol A And Arsenic In Drinking Water Using A Novel Electrode Array, Yildiz Uludağ, Zehra Ölçer, Canan Doğan, Turghun Muhammad, Zeynep Altintaş

Turkish Journal of Chemistry

The paper describes a novel dip-and-gauge hand-held sensor device for the rapid, cost-effective, and on-site detection of bisphenol A and arsenic in drinking water samples. Different working electrode diameters ranging from 1.5 mm to 4 mm were designed and fabricated to construct a new electrochemical biosensor. The sensor was employed for the chronoamperometric detection of bisphenol A and voltammetric determination of arsenic in drinking water samples. Bisphenol A measurements resulted in a detection limit of 10 ng mL$^{-1}$ with a linear range of 0-4000 ng mL$^{-1}$. Baby products and bottles have to be completely free of bisphenol and hence a …

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