bluuebunny/crossref_metadata_2025 huggingface dataset:
AES Otimizado para Uso em Aplicações IoT
Authors: Vaz Yuri Silva , Mattos Júlio C. B. , Soares Rafael Iankowski
Published: November 2023

A segurança das informações trocadas diariamente entre dispositivos IoT é uma preocupação real, visto que o número de dispositivos está crescendo exponencialmente, produzindo uma numerosa quantidade de dados que trafegam pela Internet. Uma possível solução para proteger estas informações é o uso de algoritmos criptográficos. No entanto, os algoritmos de criptografia clássicos são custosos computacionalmente não sendo adequados para execução em dispositivos IoT de baixo poder computacional e com restrições de armazenamento de dados. Neste contexto, este trabalho propõe otimizações no algoritmo criptográfico AES, de forma que sua implementação seja viável para execução em dispositivos com recursos computacionais restritos, assim, possibilitando a proteção de dados em aplicações IoT. As otimizações propostas são dedicadas especificamente aos estágios SubBytes e MixColumns. Os resultados obtidos permitem bons resultados em desempenho e ainda garantem boa qualidade da criptografia. Para validar a segurança do algoritmo com as modificações propostas é utilizado o teste de efeito avalanche, além de verificar sua melhor distribuição de 0’s e 1’s no texto cifrado comparado ao algoritmo original, e também é aprovado nos testes do NIST. Em termos de desempenho, é obtida uma redução média de 86,71% em tempo de execução, comparado à versão original do AES, o que torna esta versão otimizada atrativa para aplicações IoT.
Multi-Microgrid: Advancing Smart Grids through Hybrid IoT Architecture for Efficient Energy Management
Authors: Veloso Artur F. da S. , Silveira Jocines D. F. da , Abreu Pedro F. F. , Silva Thiago A. R. da , S. Neto Geraldo A. , Rabêlo Ricardo A. L. , R. Júnior José V.
Published: November 2023

In the current landscape, Smart Grids (SGs) grapple with critical challenges, notably their reliance on centralized networks and the absence of microgrid system integration. The concept of a multi-microgrid solution emerges as an approach that interconnects and orchestrates multiple microgrids, enhancing the electrical system’s resilience, scalability, and capacity to integrate distributed renewable energy sources, enabling Demand-Side Management (DSM) for a more efficient and secure network. This study introduces a novel hybrid Internet of Things (IoT) architecture employing LoRaWAN and LoRaMESH to address these challenges. This approach, operating within a decentralized multi-microgrid framework, reduces message transmission time by over 50%, demonstrating its efficacy and relevance while streamlining communication between Smart Meters (SMs) and the Electric Power Company (EPC), ultimately fostering the adoption of DSM services by consumers and representing a transformative solution for the future of Sgs.
Aceleração de preenchimento da tabela Q em ferramenta de automação de teste de dispositivos Android baseada em Aprendizado por Reforço
Authors: Sales Kellem , Lopes Isaac Siqueira , Carvalho Renato Lopes de , Chagas Marcele Silva das , Collins Eliane , Carvalho José Reginaldo H.
Published: November 2023

Este artigo apresenta um estudo sobre aceleração do preenchimento da tabela Q através da paralelização da ferramenta em estado da arte DroidbotX e da utilização de múltiplas instâncias, visando avaliar o seu desempenho. No contexto do mercado de aplicações móveis, a qualidade do software é um aspecto crítico que afeta diretamente a satisfação do cliente e a reputação da empresa. Nesse cenário, o teste de software é essencial para evitar que falhas graves ocorram nas mãos dos usuários finais, tornando o processo de teste um fator fundamental de sucesso, pois evitar gargalos é importante. As pesquisas com geração automática de casos de teste vêm ganhando destaque, principalmente para evitar o gargalo na fase de criação de casos de teste, que dependendo da complexidade da aplicação, precisa de esforço. Tecnologias de IA como o Aprendizado de Máquina por Reforço têm sido pesquisadas e estão apresentando potencial de sucesso nessa tarefa. Assim, neste estudo, foi feito um experimento comparativo com a ferramenta de geração de casos de teste que foi executada em quatro emuladores simultaneamente, alimentando a mesma tabela Q, e comparados os resultados com a execução em apenas um emulador. Ao longo de um período de duas horas, em dez aplicações Android, extraímos a taxa de cobertura de código para avaliar o desempenho dos diferentes cenários. Os resultados revelaram uma tendência de aumento na taxa de cobertura de código em algumas métricas ao utilizar as quatro instâncias de emuladores ao invés de uma. Espera-se que esse resultados possam contribuir para novas pesquisas e soluções na área.
Concurrent Computing for Accelerating Financial Machine Learning Model Training
Authors: Araújo Thiago S. , Künas Cristiano A. , Balreiras Dennis G. , Lorenzon Arthur F. , Navaux Philippe O. A. , Mattos Neto Paulo S. G. de
Published: November 2023

The financial market generates a large volume of data daily, allowing the increasing use of machine learning algorithms in building predictive models for the stock market. In this environment, time is a crucial factor since stock prices change daily, so the training time of models is a critical factor. This paper proposes a method to optimize the overall training time of 5 reinforcement learning algorithms that predict the weights of each stock in a stock portfolio. Experiments were conducted by varying the number of algorithms executed simultaneously. In addition, the computational characteristics of each algorithm were analyzed concerning the use of memory and processing. From the proposed combination of running the algorithms concurrently, it was possible to reduce the total training time by 33% compared to running the algorithms sequentially. Moreover, this execution led to a commendable 15% decrease in energy consumption.
Mapping a Dark Space: Challenges in Sampling and Classifying Non- Institutionalized Actors on Telegram
Authors: Jost Pablo , Heft Annett , Buehling Kilian , Zehring Maximilian , Schulze Heidi , Bitzmann Hendrik , Domahidi Emese
Published: November 2023

Crafted as an open communication platform characterized by high anonymity and minimal moderation, Telegram has garnered increasing popularity among activists operating within repressive political contexts, as well as among political extremists and conspiracy theorists. While Telegram offers valuable data access to research non-institutionalized activism, scholars studying the latter on Telegram face unique theoretical and methodological challenges in systematically defining, selecting, sampling, and classifying relevant actors and content. This literature review addresses these issues by considering a wide range of recent research. In particular, it discusses the methodological challenges of sampling and classifying heterogeneous groups of (often non-institutionalized) actors. Drawing on social movement research, we first identify challenges specific to the characteristics of non-institutionalized actors and how they become interlaced with Telegram’s platform infrastructure and requirements. We then discuss strategies from previous Telegram research for the identification and sampling of a study population through multistage sampling procedures and the classification of actors. Finally, we derive challenges and potential strategies for future research and discuss ethical challenges.
Distribution and Reception of Conspiracy Theories and Mobilization Calls on Telegram. Combining Evidence from a Content Analysis and Survey During the Pandemic
Authors: Dogruel Leyla , Kruschinski Simon , Jost Pablo , Jürgens Pascal
Published: November 2023

The ongoing COVID-19 pandemic has led to an “infodemic” characterized by the widespread dissemination of conspiracy theories and calls for resistance against measures to combat the virus. Despite increased academic attention’s focus on conspiracy theories on Telegram, existing research has two major limitations: (1) a lack of combined examination of the distribution and reception of conspiracy theories, and (2) insufficient understanding of the relationship between the reception of conspiracy messages and political attitudes, conspiracy beliefs, or political engagement. To address these gaps, our study adopts a two-pronged approach, linking the distribution and reception of conspiracy theories and mobilization calls on Telegram while exploring the implications for recipients’ conspiracy beliefs and protest behavior. Our research design includes a manual content analysis of 3,162 Telegram posts from German conspiracy-related channels (Study 1), and a survey of 318 Telegram users in these channels and 320 traditional media users (Study 2). Our results reveal characteristics of Telegram fringe group users that make them susceptible to conspiratorial and mobilizing content, such as anti-system attitudes and a readiness for protest behavior. These findings have broader implications for understanding the role of digital media in the spread of conspiracy theories and the mobilization of resistance during crises, as well as the importance of continued research on the relationship between digital media use, political attitudes, and engagement to mitigate the negative impacts of conspiracy theories and preserve democratic values.
Aus dem Channel, auf die Straße! Wie die Querdenken-Bewegung ihren Protest auf Telegram organisiert – eine quantitative Netzwerkanalyse
Authors: Schrimpf Tobias , Dvorak Jan , Reich Andreas , Vogelgesang Jens
Published: November 2023

Die Netzwerke sozialer Medien spielen heutzutage eine wichtige Rolle bei der Mobilisierung zu Demonstrationen. Insbesondere Telegram bietet viele technologische Vorteile für die Koordinierung von Protesten. Die „Querdenken“-Bewegung nutzt Telegram als primäres Kommunikationsinstrument. Bislang existieren wenige Analysen zur Struktur ihrer Kommunikation und konkreten Mobilisierung über Telegram. In einer quantitativen Inhaltsanalyse von 9.088.629 Nachrichten aus 943 Kanälen und Gruppen der „Querdenken“-Bewegung auf Telegram gehen wir dieser Forschungslücke nach. Mithilfe einer Netzwerkanalyse von geteilten Inhalten beschreiben wir die Struktur der Kommunikation, identifizieren zentrale Knoten wie den Kanal „@haintz“ und betrachten die funktionale Rolle, die sie im Netzwerk einnehmen. Anhand von Ortsnennungen in Nachrichten erkennen wir, dass „Querdenken“ vor allem in Ballungszentren wie Berlin und Stuttgart mobilisiert hat. Jedoch gibt es auch einen Mobilisierungstrend hin zu Mittel- und Kleinstädten. Zuletzt prüfen wir durch die Analyse zweier Zeitreihen, ob ein Zusammenhang zwischen den Protestaufrufen auf Telegram und der Presseberichterstattung über das Offline-Protestgeschehen besteht. Die mittlere Korrelation zwischen den Zeitreihen interpretieren wir als Beleg der mobilisierenden Kraft von Protestaufrufen auf Telegram.
Mebudipine as an Overlooked Cardioprotective Drug: A Review Study
Authors: Rahimi Petrudi Nima , Seyfi Shahram , Hassanshahi Jalal
Published: November 2023

Context: Calcium channel blockers (CCBs) play a crucial role in the treatment of cardiovascular diseases. Mebudipine, a dihydropyridine derivative CCB, was first synthesized in 1997. This study explores the potential benefits of mebudipine in managing cardiovascular disease, particularly as a derivative of nifedipine. Evidence Acquisition: The article succinctly presents the advancements in mebudipine research, which were uncovered through extensive searches in reputable scientific databases such as ScienceDirect, Google Scholar, Scopus, and PubMed, conducted by 2 blinded researchers. The search focused on studies relevant to mebudipine, using specific keywords. Results: Mebudipine exhibits cardioprotective effects, reducing the occurrence of arrhythmias and minimizing heart tissue damage. Additionally, it has been found to enhance the levels of nitric oxide metabolites. Due to its limited solubility in water, mebudipine is typically administered using a nanoemulsion. Importantly, it has been deemed a safe drug without mutagenic effects. Conclusions: Our review study underscores that mebudipine not only has a cardioprotective effect but also offers protection to other organs against various forms of injury induction. The mechanisms responsible for these protective effects may be linked to its ability to counteract oxidative stress, prevent apoptosis, and mitigate inflammation. Nevertheless, further research is needed to fully elucidate its potential.
Glucose Metabolism in Acute Myeloid Leukemia Cell Line Is Regulated via Combinational PI3K/AKT/mTOR Pathway Inhibitors
Authors: Ranjbar Abbas , Soltanshahi Mohsen , Taghiloo Saeid , Asgarian-Omran Hossein
Published: November 2023

Background: Metabolism reprogramming is a survival mechanism in acute myeloid leukemia (AML) cells in the tumor microenvironment. Therefore, we investigated the effect of signaling pathway inhibitors on the expression of genes rewired in the metabolic pathway of AML cells. Methods: HL-60 cells were treated with Idelalisib, MK-2206, and Everolimus, which respectively are selective inhibitors of phosphatidylinositol-3-kinase (PI3K), AKT, and the mammalian target of rapamycin (mTOR), either individually or in combination. The relative expressions of Glucose Transporter 1, Hexokinase 2, Pyruvate Kinase, Pyruvate Dehydrogenase E1, Citrate synthase, Isocitrate Dehydrogenase 2, and Hypoxia Inducible Factor 1 Subunit Alpha were determined by real-time PCR. Results: The combined treatment of HL-60 cells with Idelalisib, MK-2206, and Everolimus decreased the expression of Glucose Transporter 1, Hexokinase 2, Pyruvate Kinase M2, Pyruvate Dehydrogenase E1, Citrate synthase, Isocitrate Dehydrogenase 2, and Hypoxia Inducible Factor 1 Subunit Alpha. Conclusions: A combination of PI3K/AKT/mTOR pathway inhibitors regulates the expression of genes involved in glycolysis, Pyruvate Dehydrogenase Complex (PDH), and the tricarboxylic acid (TCA) cycle and interferes with metabolic reprogramming and immune evasion mechanisms of AML leukemic cells. Combinational therapy approaches to block these pathways might be a promising and novel therapeutic strategy for targeting the metabolic requirements of AML cells.
Long COVID Effects on Level of Physical Activity and Health-Related Quality of Life in the Post-infection Period: A Cross-sectional Study
Authors: Shanbehzadeh Sanaz , Zanjari Nasibeh , Ebrahimabadi Zahra , Askary Kachoosangy Reihaneh , Niknam Hoda , Basikhaste Fahime
Published: November 2023

Background: Long COVID is a major manifestation of long-lasting symptoms experienced by the survivors of the coronavirus infection that may influence patients’ physical and mental health. Objectives: This study aimed to evaluate the association of the physical symptoms of COVID-19 (fatigue, breathlessness, and pain) and the level of physical activity with the physical and mental health of survivors in the post-COVID-19 period. Methods: This was a cross-sectional study conducted on 152 hospitalized and non-hospitalized adults infected with COVID-19 aged between 18 and 65 years at the post-infection period with follow-up times greater than 6 months. Standardized instruments, such as the SF12, International Physical Activity Questionnaire (IPAQ), Multidimensional Fatigue Inventory (MFI-20), and visual analog scale (VAS), were used for measuring pre-and post-COVID-19 painful symptoms, fatigue, and breathlessness. The severity of the coronavirus infection was judged based on hospitalization or ICU admission. Data were analyzed with linear regression analysis. Results: The results showed that, at a mean duration of 6 months post-discharge, only fatigue was associated with lower physical (F = 2.84, explained variance = 15.3%) and mental health (F = 1.88, explained variance = 10.6%) Conclusions: Considering the negative impact of fatigue on the physical and mental health of patients during the post-COVID period, it is suggested to monitor and manage fatigue for a longer period post-COVID-19.
Efektivní porušení práva
Authors: Bejček Josef
Published: November 2023

Řada subjektů vědomě poruší smlouvu s cílem získat pro sebe výhodu na úkor jiných či v neprospěch veřejného zájmu. Sankce se přitom pokládá za přijatelnou „cenu“ takového porušení. Koncepce tzv. efektivní protiprávnosti se prezentuje jako protipól tradiční mravní i právní zásady „pacta sunt servanda“ a zdůrazňuje větší flexibilitu a svobodu smluvních stran, jež si cení více vlastního užitku z porušení smlouvy nežli dobrého pocitu z věrnosti smluvnímu závazku. Ještě vyostřenější je rozšíření tohoto přístupu k plnění povinnosti stanovených zákonem. Článek nejprve obecně rozebírá ideová a hodnotová východiska teorie efektivního porušení. Dovozuje se, že efektivní porušení smlouvy je na úvaze každé ze stran a je spojeno s případnými odpovědnostními důsledky. Přípustnost tzv. efektivního porušení však nelze mechanicky přenášet do oblastí, v nichž povinnost právně konformního jednání plyne ze zákona. S pomocí praktických příkladů se kritizuje relativizace zákonného standardu péče řádného hospodáře člena orgánu obchodní korporace, zdůvodněná „efektivností“ porušení zákona pro korporaci. Pravidlo podnikatelského úsudku nelegitimizuje porušení zákona v údajném obhajitelném zájmu korporace. Zdůvodňuje se stanovisko, že loajalita ke korporaci nemůže stát nad loajalitou k zákonu.
Fikcionalismus, princip užitku a aplikace práva
Authors: Barták Daniel
Published: November 2023

Článek se zabývá fikcionalismem a jeho užitím v návaznosti na proces aplikace práva. Soustředí se na dva prvky v tomto procesu a vysvětluje, proč zakládají jeho fiktivnost, čímž se snaží upozornit na nedokonalost teoretického zpracování této problematiky. Fiktivnost procesu aplikace práva je vystavěna na dvou tezích. Zaprvé, subsumpce zakládá fikci personifikace a zadruhé, poznatky novověké epistemologie vedou k závěru, že nelze aplikovat právo ale pouze představu o tom, co je právo. Cílem tohoto textu je představit další možný způsob, kterým lze na aplikaci práva nahlížet a zároveň rozšířit povědomí o četnosti fikcí v právu. Dále má upozornit na možnost užití principu užitku ve fiktivním prostředí.
K výkladu a použití čl. 66 Ústavy. Příspěvek k ústavním dějinám roku 2021
Authors: Kysela Jan
Published: November 2023

Koronavirová pandemie ukázala důležitost zastupitelnosti konkrétních vykonavatelů veřejné moci. Na ústavní úrovni jsou u nás pravidla náhradního výkonu funkcí obsažena jen výjimečně. Tento článek analyzuje úpravu a dosavadní praxi náhradního výkonu funkce prezidenta republiky. Všímá si historických úprav a vykládá pravidla současná. Zvláštní pozornost je věnována dvěma případům z roku 2021, kdy byla senátory zvažována aktivace náhradního výkonu funkcí prezidenta republiky Miloše Zemana.
Specifika účasti veřejnosti v postupech podle zákona o nakládání s těžebním odpadem
Authors: Hak Jan
Published: November 2023

Zbytky po těžbě nerostů mohou představovat značné riziko pro životní prostředí, ale i pro životy, zdraví a majetek osob v okolí. Především z nich mohou unikat některé toxické těžké kovy, které se pak následně dostávají i do potravního řetězce, nebo může v místě docházet k sesuvům atp. Je proto v zájmu veřejnosti, aby se mohla k nakládání s těžebním odpadem vyjadřovat a přímo tak v konečném důsledku ovlivnit, zda v jejím sousedství dojde ke zřízení úložného místa pro těžební odpad, jak bude toto místo provozováno a co se s ním bude dít po jeho uzavření. Následující článek se proto zaměřuje na možnosti účastenství, resp. obecněji zapojení veřejnosti do procesů upravených v zákoně č. 157/2009 Sb., o nakládání s těžebním odpadem a o změně některých zákonů (v textu jako „ZNTO“), který doposud větší pozornosti uniká.Článek poukazuje na to, že česká právní úprava pro nakládání s těžebními odpady odpovídá sice směrnici 2006/21/ES z hlediska požadavků na minimální nezbytné zapojení veřejnosti, na druhou stranu u řady dalších řízení v ZNTO (změnová řízení, deklarace uzavření úložného místa, nakládání s finanční rezervou, udělování výjimek a nápravných opatření či řízení o pochybnostech) není výčet jejich účastníků zřejmý, je třeba jej dovozovat skrze účel jednotlivých řízení a podpůrné použití správního řádu. To nepřispívá k právní jistotě adresátů ZNTO a může je od intenzivnějšího zapojení v konečném důsledku odrazovat.
Problematika regulácie vzdialeného vodiča z pohľadu teórie a praxe
Authors: Andraško Jozef , Mesarčík Matúš
Published: November 2023

Problematika automatizovaných vozidiel už nie je len predmetom vedecko-fantastickej literatúry, ale čoraz viac členských štátov prijíma regulácie predmetného fenoménu. Predkladaný článok sa venuje problematike úzko súvisiacej – vzdialeného vodičovi. Rola vodiča, ktorý ovláda automatizované vozidla na diaľku môže byť iná z pohľadu povinností v tradičnom vnímaní vodiča motorového vozidla. Predkladaný článok sa zameriava na oblasť automatizovaných vozidiel z pohľadu role a povinností vzdialeného vodiča. Cieľom tohto článku je v prvom rade porovnať rolu vodiča klasického vozidla a vzdialeného vodiča automatizovaného vozidla. V druhom rade autori ponúkajú diskusiu a odporúčania pre právnu úpravu v kontexte povinností a otvorených otázok praktického fungovania vzdialeného vodiča.
Diabetes Mellitus 2 de nueva aparición después de la cirugía bariátrica
Authors: Silvana Yolanda Omonte Gonzales , Condori Barrozo Jose Miguel
Published: November 2023

En Bolivia al igual que en otros países la prevalencia de la diabetes mellitus tipo 2 en personas con obesidad continúaen gran ascenso por lo que es importante el estudio de las intervenciones terapéuticas dirigido a este tipo de patologíascrónicas. El objetivo de la presente revisión es presentar resultados de la literatura actual sobre el rol de la cirugía bariátricaen el control de la DM2 y obesidad, así como los factores que intervienen en la recaída después de una remisión inicial.Para lo cual se utilizó base de datos como Google académico, Hinari, PubMed, y Cochrane. Se analizó los beneficios de losdos tipos de cirugía metabólica más utilizados en cuanto a remisión de la DM2 se refiere, así como los factores predictoresde riesgo de recaída que hasta la actualidad no supera los beneficios.
Further additions to the knowledge of Strumigenys (Formicidae: Myrmicinae) within South East Asia, with the descriptions of 20 new species
Authors: Tang Kit Lam , Guénard Benoit
Published: November 2023

The species of the ant genus Strumigenys Smith, 1860 from Southeast Asia are reviewed based on recent sampling efforts as well as unreported historical material from southern mainland China, Japan, Taiwan, Thailand and Vietnam. We report 42 new species records for these regions. A total of 20 species new to science are described: S. anhdaoae sp. nov., S. claviseta sp. nov., S. crinigera sp. nov., S. decumbens sp. nov., S. delicata sp. nov., S. densissima sp. nov., S. doydeei sp. nov., S. fellowesi sp. nov., S. intermedia sp. nov., S. jaitrongi sp. nov., S. liuweii sp. nov., S. longidens sp. nov., S. mediocris sp. nov., S. rongi sp. nov., S. scutica sp. nov., S. strummeri sp. nov., S. xenopilus sp. nov., S. yamanei sp. nov., S. zanderi sp. nov. and S. zhenghuii sp. nov. The descriptions of the existing species S. elegantula (Terayama & Kubota, 1989) and S. nathistorisoc Tang et al., 2019 are revised. Strumigenys formosensis Forel, 1912 syn. nov. is synonymized with S. feae Emery 1895 in the light of recently collected specimens. Three species complexes are created within the S. leptothrix-group: elegantula-complex, leptothrix-complex and zanderi-complex, based on differences in dentition. A new species group, S. nathistorisoc-group, is introduced. The key to Strumigenys of East Asia (as Pyramica) by Bolton is partially revised to accommodate species from these species groups that were described since the publication of the key. Finally, the implication of our results to the region and the current limitation of species groups and complexes of the genus is discussed. A correction has been published: Tang K.L. & Guénard B. 2024. Further additions to the knowledge of Strumigenys (Formicidae: Myrmicinae) within South East Asia, with the description of 20 species – Corrigendum. European Journal of Taxonomy 917: 194–197. https://doi.org/10.5852/ejt.2024.917.2399
Combination of gold nanoparticles and lycorine for enhancing anti-inflammatory activity
Authors:   , Payuyong Varayukrit
Published: November 2023

Inflammation is a complex biological response of tissues to harmful stimuli, such as pathogens. NSAIDs are commonly used to reduce inflammatory activities; however, some types of NSAIDs have side-effects on patients. Importantly, in this study attention the naturally occurring substances from plant to development of new drugs to treat inflammatory activities. Recently, Lycorine is one of the major alkaloids that have been isolated from the Amaryllidaceae plant has been reportedly possessed the anti-inflammatory activity. It is a good therapeutic candidate against inflammation which can inhibit the expression of cytokines.

Recently, gold nanoparticles (AuNPs) have been used in medicinal applications due to their unique properties such as high chemical stability, high biocompatility. AuNPs as carriers for the delivery of drugs, genetic materials and proteins resulting in enhanced their activities. For the anti-inflammation, AuNPs also inhibit the expression of NF-kappa B, a protein that acts to stimulate inflammation. In order to enhance the activation of the Lycorine, AuNPs have been employed.

Finally, this work compared the performance of lycorine, Au@P, and Ly+Au@P towards RAW 264.7 cells using LPS-induced NO tests. The results demonstrated that Lycorine could inhibit similar to budesonide in NO production. The inhibition doses was 10 µM for Ly+Au@P This work showed a successful inhibition agent derived from the excellent combination of Lycorine and Au@P. The synthesis of AuNPs using pullulan that has a particles size about 10 nm. The shape is spherical shape by TEM technigue.
The Experiences of Private Competition Enforcement in the United States, the European Union, Japan, Singapore and Malaysia: Lessons for Thailand
Authors:   , Sirikan Nutavit
Published: November 2023

Section 40 of Trade Competition Act, B.E. 2452 (1999) entitles private parties to bring claims for damages against violators who violate Sections 25, 26, 27, 28 and 29. However, the experience and study of the provisions on private antitrust/competition enforcement in the selected jurisdictions, namely the United States, the European Union, Japan, Singapore and Malaysia indicates that a claim for damages is one of the means, inter alia, of actions that private individuals can employ to enforce the antitrust/competition law. Moreover, Section 40 of Trade Competition Act, B.E. 2452 (1999) has two critical legal issues regarding the interpretation of the ambiguous wordings thereof. First, it is questionable as to whether private plaintiffs can initiate the claim for damages without any prerequisite. The second issue is related to the application of the law with respect to the standard of proof of the plaintiffs. This thesis puts forward the new amendment to Section 40 of Trade Competition Act, B.E. 2452 (1999) in order to make the wording clearer and enhance the effectiveness of enforcement. In other words, the decision of the Commission is a prerequisite to the exercise of rights of private claims for damages. This implementation will plausibly ease the burden of proof of the plaintiffs, and increase an opportunity for the plaintiffs to obtain compensation. Furthermore, the statute of limitations provided in Section 41 should also be amended in order that it will be consistent with the new amendment of Section 40 of the Act.
Development and characterization of bacterial cellulose/natural rubber composite films
Authors:   , Potivara Kornkamol
Published: November 2023

The composite of bacterial cellulose (BC) and natural rubber (NR) has been developed in this study to combine the prominent properties between strength from three-dimensional structure of BC nanocellulose and flexible molecular chain of isoprene (C5H8). BC membranes were produced by A. xylinum using coconut-water medium under static incubation for 5 days.  The BC membrane were then purified and immersed in NR latex solution at various concentrations (0-10 % v/v). The influence immersion temperature (30°C, 50°C, 60°C and 70°C) and a ratio of ethanol in the solvent were also investigated.  The results were compared with the unmodified BC. NR particles were characterized by Laser particle size distribution (PSD), the morphology and cross-section of films by Field Emission Scanning Electron Microscopy (FESEM), functional groups and intermolecular interactions by Fourier Transform Infrared Spectroscopy (FTIR), the crystallinity structure by X-ray diffraction (XRD), the thermal properties of composite films by Differential Scanning Calorimetry (DSC), the mechanical properties by Instron testing machine, the water absorption capacity, toluene uptake and biodegradable in soil measurements. According to the experiments, the addition of a certain amount of ethanol slightly affected NR particle size but helped reduce the viscosity of NRL, resulting in more penetration of NR molecules into BC. The optimal condition was the immersion at 2.5–5.0 % NR latex solution, under the temperature of 50-60°C, where the thickness of the composite could be enhanced from ~12 μm of the unmodified BC to ~20-27 μm. The crystallinity structure of the composite films remained as BC structure. The new peak was not occurred from FTIR analysis; however a slight shift of hydroxyl peaks might indicate some weak physical interactions between BC and NR. The results show that the water absorption decreased and the toluene uptake increased as compared to normal BC film. Moreover, the tensile strength and elongation at break of the NR-BC composited films were significantly improved for 3-6 folds in comparison to the normal BC film. The results of biodrgradation in soil showed that the composite films could completely degrade for 5-6 weeks.
Development of epoxy adhesive for screen printing on aluminum of flexible printed circuit
Authors:   , Leeium Piyarat
Published: November 2023

The aim of this research is to develop epoxy based adhesive for screen printing on aluminum (Al) and polyimide (PI) substrates in flexible printed circuit (FPC) manufacturing. Two types of aromatic epoxy resins are evaluated in this work including diglycidyl ether of bisphenol-A (DGEBA) and epoxy phenolic novolacs (EPN). The two epoxy resins will also be blended with aliphatic epoxy (PPGDE) for adhesive property enhancement purpose. These epoxy systems can be cured at 170oC for 15 min using metaphenylene diamine (m-PDA) as a curing agent. The compositions of the aromatics epoxies were varied in a range of 50 to 90wt%. From the results, it was found that peel strength of EPN/PPGDE blends was higher than peel strength obtained from DGEBA/PPGDE systems. The maximum peel strength of EPN/PPGDE blends was measured to be 0.561 N/mm at 50/50 mass ratio. These blends were also found to show outstanding adhesive bonding with the aluminum substrate. In addition, it was also found that when the EPN/PPGDE blend at 50/50 mass ratio was modified with 5 phr of CTBN rubber, the resulting adhesive exhibited a good bonding with polyimide substrate providing maximum peel strength of about 0.706 N/mm. The above results also suggest difference in bonding mechanisms of the two adhesive layers and the Al or PI substrates. Consequently, two adhesive layers of epoxy systems with the first layer of EPN/PPGDE blend was applied on Al substrate whereas the CTBN modified EPN/PPGDE blend, a second adhesive layer, which provides a good adhesion on PI film was casted on top of the EPN/PPGDE layer. The obtained peel strength of this two-layered epoxy blends was found to be as high as 0.813 N/mm meeting the industrial requirement. These two-layered epoxy adhesive systems are a good candidate for adhesive bonding of Al and PI substrates through screening printing process.
Comparison of hydrolysis methods for removal of glycerides in rice bran acid oil
Authors:   , Meedam Amornrat
Published: November 2023

The objective of this study is to determine the suitable hydrolysis method for removal of glycerides in rice bran acid oil based on the percentage of glycerides conversion, remaining content of γ-oryzanol and antioxidant activity. The experiment was divided into two parts. Firstly, three hydrolysis methods consisting of subcritical water hydrolysis, acid-catalyzed hydrolysis and base-catalyzed hydrolysis were compared. The suitable methods were selected and were evaluated in the second part to determine the suitable hydrolysis conditions.  Subcritical water hydrolysis and base catalyzed hydrolysis was found to give higher percentage of glycerides conversion than acid catalyzed hydrolysis, while the antioxidant activities of the reaction products obtained from various methods did not differ significantly. Therefore in suitable conditions were then determined for these two methods. Base on the percentage of glycerides conversion and remaining content of γ-oryzanol, the most suitable temperature and time for subcritical water hydrolysis was 200°C and 30 minutes, respectively. At this condition, the percentage of glycerides conversion and the remaining content of γ-oryzanol were 86.49±1.18 and 80.34±1.80 % respectively. For base-catalyzed hydrolysis, the most suitable condition is 2.5N sodium hydroxide solution at 90 °C, and the reaction time between 5 to 10 minutes. At these conditions, glycerides were completely removed and the content of γ-oryzanol remained in hydrolyzed product were 56.48±1.54 % and 65.88±0.25 % for the reaction time of 5 and 10 minutes, respectively. Moreover, the antioxidant activity of hydrolyzed products obtained from base-catalyzed hydrolysis was found to be the higher than that obtained from subcritical water hydrolysis.
OXIDATIVE DEHYDROGENATION OF ETHANOL OVER Cu-AgLi/Al2O3 CATALYSTS
Authors:   , Sukarawan Nasrada
Published: November 2023

In this research, the effect of copper and silver weight ratio (Cu:Ag of 100:0, 70;30, 50:50, 30:70, 0:100) supported on mixed-phase of Al2O3 catalysts was investigated. The mixture of equal phase between gamma- and chi-Al2O3 support was synthesized via the solvothermal method. The support was brought to loading with copper, silver (5 wt%), and lithium (0.7 wt%) that was prepared via incipient wetness impregnation technique. The catalytic activity was identified through the ethanol dehydrogenation and oxidative dehydrogenation reactions in packed-bed reactor at 200 to 400oC under atmospheric pressure. The performance in the reaction was found that Cu(0)Ag(100)Li/M-Al showed the highest acetaldehyde yield and ethanol conversion in all reaction temperatures of dehydrogenation reaction study because of its high specific surface area and the large amount of total basicity. Especially, the highest acetaldehyde yield of 81% existed at 350oC. This catalyst also displayed the excellent value of acetaldehyde yield in oxidative dehydrogenation that given the highest yield at 300oC of 92%. In addition, Cu(30)Ag(70)Li/M-Al showed the greatest yield at the lowest temperature of studied reaction temperature, 250oC with acetaldehyde yield of 59%. Along the stability test in time-on-stream for 10 hr, the comparison result between dehydrogenation and oxidative dehydrogenation revealed that the addition of oxygen can prevent the deactivation of catalysts via coke formation and metal sintering. Cu(0)Ag(100)Li/M-Al, which was reacted in oxidative dehydrogenation of ethanol at 300oC had the lowest coke deposition on catalyst surface compared to itself reacted in dehydrogenation at 350oC and Cu(30)Ag(70)Li/M-Al reacted in oxidative dehydrogenation at 250oC.
NON-FARADAIC ELECTROCHEMICAL MODIFICATION OF CATALYTIC ACTIVITY (NEMCA) OF PROPANE OXIDATION AT THIN-FILM CELL ON ALUMINA
Authors:   , Limsrimongkonchai Pattamon
Published: November 2023

Non-faradaic electrochemical modification of catalytic activity (NEMCA) of propane oxidation has been studied. It is a potential phenomenon that could become a breakthrough in improvements on catalytic converters. Yttria-stabilized zirconia (YSZ, Y2O3:ZrO2) ionic conductors, was deposited on alumina substrates by sputtering technique carried out in vacuum in the form of a thin film deposited on a cheaper alumina support. NEMCA of propane oxidation was studied under a stoichiometric ratio of propane to oxygen at 200-500 °C in both open-circuit (i.e., with no current passing through the electrolyte) and closed-circuit conditions with wired configuration cell between wireless and conventional methods. The highest catalytic CO2 production rate is 1.98 x 10-8 mol/s by wireless method operated by sputtering at 400 W for 4 h while in case of conventional method, at 500 °C with YSZ thin film cells, the reaction rate exhibited the electrophobic type of NEMCA (i.e., the promoting effect at positive potentials) at closed-circuit condition. However, reversibility of reaction rates was observed during forward and reverse potential scans at 400°C for sputtering time 4 h and 200 °C for sputtering time 8 h. Moreover, screen-printing technique was also fabricated YSZ thin film on alumina. By wireless method, the maximum rate enhancement ratios was 2 times at 60wt% YSZ ink and by conventional method, the maximum rate enhancement ratios was 1.31 times.
Preparation of silica coated with polyethylene by in situ polymerization with metallocene catalyst
Authors:   , Jamnongphol Sineenart
Published: November 2023

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CO2 CAPTURE FROM FLUE GAS BY POTASSIUM-BASED SORBENT IN CIRCULATING-TURBULENT FLUIDIZED BED
Authors:   , Chaiwang Pilaiwan
Published: November 2023

The purpose of this research is to study the carbon dioxide capture process using solid sorbent in a circulating fluidized bed reactor. From previous research work, it was found that the hydrodynamics under circulating turbulent fluidized bed (CTFB) regime can promote the solid sorbent for CO2 capture process, due to the combination of advantages of fast fluidization and turbulent regimes. The solid sorbent being used in this study was potassium carbonate on alumina supporter. The study started with finding the operating condition in the riser so that the particles flow in the reactor fell in the circulating turbulent fluidization regime. The experiment showed that when the gas velocity is 1 m/s, the flow will be performed in the CTFB regime and it was confirmed by the uniform distribution of solid volume fraction along the riser. The solid volume fraction in this case was 0.15. Then, the kinetic of the adsorption under several operating flow regimes in the riser was studied and the kinetic parameters corresponding to each regime were determined using deactivation kinetic model. The estimated parameters showed that the kinetic of the circulating turbulent fluidized bed and the bubbling fluidized bed were quite similar. For the completion of the system, the research also studied the downer reactor which functions to regenerate the spent sorbent by studying the hydrodynamics and kinetic inside the reactor. The hydrodynamic was studied by using 2D computational fluid dynamic model. The adjustment of pressure drop (0.90 – 0.99 atm) and recirculating rate of the particles (250 – 1000 kg/m2.s) were simulated and the results showed that the particles have higher mean free path when the recirculating rate of the particles was lower. For the kinetic of KHCO3 sorbent regeneration, the thermogravimetric method was conducted under nonisothermal condition to determine the kinetic parameters and the analytical method model was selected to represent the regeneration model.
Synthesize of iso-paraffin fuels from palm oil over heterogeneous acid and base catalysts
Authors:   , Trieu Quang
Published: November 2023

This study focused on the synthesis of hydrocarbon fuel containing a high iso-paraffin and very low oxygen content from palm oil using a mixed acid-base catalyst. The catalysts were characterized by nitrogen adsorption-desorption, X-ray diffraction, hydrogen-temperature programmed reduction, carbon dioxide- and ammonia-temperature programmed desorption as well as thermogravimetric analysis.  Solid base (MgO, CaO, SiO2 and Na2SiO3) and solid acid (HY, H-beta, HZSM5 and Al2O3) catalysts were individually evaluated for their catalytic activity in a semi-batch reactor in terms of the deoxygenation level of palm oil. The best acid and alkali catalyst were then selected for mixing at different volume ratios for catalytic deoxygenation of palm oil. Finally, the reaction temperature (400–460 oC), residence time were optimized. The main components in the liquid product obtained were normal paraffins, iso-paraffins, olefins and aromatics. For the single base catalysts, a liquid yield of higher than 65 wt.% was obtained at a 460 oC using MgO catalyst, which also realized an excellent decarboxylation and decarbonylation. For the single acid catalysts, the zeolite beta catalysts reached a liquid yield of around 55 wt.% with a high iso-paraffin content. The optimal MgO: beta zeolite ratio for the acid-base hybrid catalyst was 3:1, which resulted the products with a high iso-paraffin content (25% and 35% in nitrogen and hydrogen atmosphere, respectively).
SYNTHESIS OF COMPLEX GOLD NANOSTRUCTURES INDUCED BY SILVER ION
Authors:   , Pangdam Apichat
Published: November 2023

In this work, we exploited a unique reaction of silver ions to create and design urchin-like gold microstructures (UL-AuMSs) with controllable length of nanothorns. The UL-AuMSs were synthesized via a simple one-pot synthetic protocol without using any surface capping agents or polymeric stabilizers. The reactants consisted of tetrachloroauric (III) acid, silver nitrate, and hydrogen peroxide (H2O2). H2O2 functioned as the sole reducing agent while trace silver ions played an important role as the shape controlling agent. Without trace silver ions, quasi-sphere gold microstructures (QS-AuMSs) were obtained. The time-dependent SEM investigations corroborated that UL-AuMSs and QS-AuMSs grew from flower-like gold microstructures (FL-AuMSs). The added trace silver ions reacted with physically adsorbed chloride ions on gold surfaces and formed into solid silver chloride capable of altering the dendritic growth of QS-AuMSs to the dominated trunk-growth of UL-AuMSs. The cleaned UL-AuMSs with average thorn lengths of 166 and 187 nm expressed high SERS activity as 0.1 nM of Rhodamine 6G could be detected with a short 15-min incubation. The easily visualized UL-AuMSs under a microscope assisting the SERS detection at selected spots was demonstrated.
Substrate and oseltamivir binding into influenza virus neuraminidase by molecular dynamics simulations
Authors:   , Phanich Jiraphorn
Published: November 2023

Neuraminidase (NA), a glycoprotein on influenza virus membrane, attachs to the terminal sialic acid (SIA) then cleaves the glycosidic linkage from the subsequent sugar of host cell receptor to release new virions. Types of receptor based on glycosidic linkage are SIA-2,3-GAL-1,4-NAG (3SL) and SIA-2,6-GAL-1,4-NAG (6SL). NA has been an important target for developing anti-influenza agents; however, the substrate binding and specificity of NA are not well understood. In addition, the widespread use of NA inhibitor leads to the mutation of gene. For instance, the pandemic of novel H7N9 virus has a R292K substitution of NA conferring oseltamivir resistance. Therefore, this work aims to understand the substrate binding into NAs from H1N1, H2N2 and H3N2 human viruses and H5N1, H7N9 avian viruses as well as to elucidate insight into oseltamivir resistance of H7N9 substitution using MD simulations and binding free energy predictions. QM/MM-GBSA binding free energies predicted that NAs of human viruses show strong binding to 6SL, whereas avian NAs have preference for 3SL. Although SIA is the main part of glycan for binding into NA, the difference of binding patterns is caused by the diversity of 6SL revealing the rotation of torsion angles between GAL and NAG. The prediction of oseltamivir susceptibilities of H7N9 NA using MM/PB(GB)SA and MM/3D-RISM is in good agreement with the experimental data. The primary source of oseltamivir resistance is due to the decrease of drug-target interaction. The shorter side chain of lysine at mutated residue results in the loss of hydrogen bond forming with carboxylate group and increasing of water molecules.
Transformation of organic compounds by transition metal salts in ionic liquids
Authors:   , Taboonpong Piyada
Published: November 2023

A new, convenient, and high yielding synthetic protocol for transformation via oxidation process of various organic compounds using a combination of 1-hexyl-3-methylimidazolium bromide ([hmim]Br) and a transition metal salt, such as FeCl3, and CuCl2 is uncovered. The oxidation of alcohols utilizing FeCl3/[hmim]Br in the presence of tert-butyl hydroperoxide (TBHP) afforded the corresponding carbonyl compounds in high yields. Primary and secondary benzylic alcohols seem to be reactive substrates for conversion to the desired carboxylic acids and ketones, respectively, without by-products formed. For aromatization of cyclic dienes catalyzed by CuCl2 coupled with TBHP in [hmim]Br, cyclic hydrocarbons yielded highly amount of the expected aromatic substances under short reaction time, while heterocyclic amines furnished the expected heteroaromatics in moderate yield. Consequently, the developed catalytic system of a transition metal salt/[hmim]Br displayed the reusability in this methodology. For the dehydrogenation of N-heterocycles, FeCl2/DMSO combination under oxygen atmosphere offered the corresponding N-heteroaromatic products in good yields via radical involving process, the catalytic system operated better under conventional organic solvents than ionic liquids.