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Comparative Analysis of End Device and Field Test Device Measurements for RSSI, SNR and SF Performance Parameters in an Indoor LoRaWAN Network

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WIRELESS PERSONAL COMMUNICATIONS 2024年第1期134卷 339-360页

作者： Aksoy, Ataberk Yildiz, Oemer Karlik, Sait Eser Bursa Uludag Univ Grad Sch Nat & Appl Sci MSc Program Elect Engn Bursa Turkiye Bursa Uludag Univ Grad Sch Nat & Appl Sci PhD Program Elect Engn Bursa Turkiye Bursa Uludag Univ Fac Engn Dept Elect & Elect Engn Bursa Turkiye

Internet of things phenomenon has brought up distinctive technologies that are using wireless communication and appearing in smart city applications. Long range (LoRa) modulation technique has pulled up the market and forced the announcement of LoRa wide area network (LoRaWAN) standard in 2021 by ITU-T with Y.4480 standard code. LoRaWAN is a medium access control protocol using low power wide area network approaches with the aim of long-range coverage and management of many end devices. LoRaWAN networks are emerging all over the world with some existing optimization, planning and network allocation problems that need to be overcome. This paper focuses on comparative analysis and interpretation of measurements performed in a LoRaWAN network deployed in an 18-floor building with a LoRaWAN gateway on the roof. The research covers results of comparative measurements between end device and Adeunis field test device (AFTD) for received signal strength indicator (RSSI), signal-to-noise ratio (SNR) and spreading factor (SF). End devices have been randomly selected from 18th, 12th, 6th and 1st floors and their daily performance data have been gathered through the network server. AFTD has been used to get 100 sample measurements for each floor. Maximum and average RSSI values obtained from end device measurements are higher than ones measured with AFTD except the case in the 18th floor. Excluding the maximum SNR values at the 1st and the 18th floors, all SNR values measured with AFTD are higher than ones obtained from end device measurements. SF measurements show that higher SF values are more likely to be used with increasing distances to the gateway as expected from the theoretical background.

关键词： IoT LoRa LoRaWAN Chirp spread spectrum Smart city

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Process optimization for ammonium removal from municipal food waste treatment plant liquid digestate using natural rocks and volcanic ash

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BIOMASS & BIOENERGY 2025年 193卷

作者： Arellano-Yasaca, Diana Victoria Chu, Chen-Yeon Rios-Garcia, Ivan Jusoh, Wan Nazihah Liyana Wan Feng Chia Univ PhD Program Infrastruct Planning & Engn Taichung 40724 Taiwan Feng Chia Univ PhD Program Civil Engn Water Resources Engn & Infr Taichung 40724 Taiwan Feng Chia Univ Inst Green Prod Taichung 40724 Taiwan Univ Nacl Chimborazo Fac Ingn Grp Invest Estudios Interdisciplinarios Ingn Ambiental Riobamba 060103 Chimborazo Prov Ecuador Univ Kebangsaan Malaysia Fac Engn & Built Environm Dept Chem & Proc Engn Bangi 43600 Selangor Malaysia

This study investigates the adsorption of ammonium (NH4+) from the liquid fraction of food waste digestate. Six natural rocks and volcanic ash were used as adsorbents. X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) were employed to analyze mineral composition and surface morphology before and after adsorption. Results indicated a significant ammonium reduction of up to 64 %, with an adsorption capacity of 93 mg L- 1 at equilibrium within 50 min. After adsorption, changes in the XRD patterns and mineral composition confirmed transformations in the adsorbents, SEM revealed rough and irregular surface morphologies, likely attributed to the uptake of NH4+, and EDS analysis showed a decrease in the concentration of exchangeable cations, which was associated with increased nitrogen levels in each rock sample. These findings suggest that the primary mechanism of these materials for NH4+ adsorption is cation exchange. Additionally, generated models for nitrogen removal efficiency (NRE) and adsorption capacity (AC) concluded that factors such as pH, adsorbent dosage, and temperature also influenced adsorption efficiency. Triplicate experimental runs and ANOVA confirmed the models' predictive accuracy, yielding an R2 of 0.9955, a standard deviation of 1.02, and a minimal variability of 2.63 % for NRE. Optimal conditions were identified at a pH of 6, a dosage of 0.32 g, and a temperature of 23 degrees C, achieving an NRE of 62 % and an AC of 159 mg g- 1. Efficient ammonium adsorption by these natural adsorbents shows promise for practical wastewater treatment and environmental remediation.

关键词： Ammonium adsorption Cation exchange Natural rocks Surface morphology Volcanic ash X-ray diffraction

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ATR blocks telomerase from converting DNA breaks into telomeres

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SCIENCE 2024年第6684期383卷 763-770页

作者： Kinzig, Charles G. Zakusilo, George Takai, Kaori K. Myler, Logan R. de Lange, Titia Rockefeller Univ Lab Cell Biol & Genet New York NY 10065 USA Weill Cornell Rockefeller Sloan Kettering Triinst MD PhD Program New York NY 10065 USA

Telomerase, the enzyme that maintains telomeres at natural chromosome ends, should be repressed at double-strand breaks (DSBs), where neotelomere formation can cause terminal truncations. We developed an assay to detect neotelomere formation at Cas9- or I-SceI-induced DSBs in human cells. Telomerase added telomeric repeats to DSBs, leading to interstitial telomeric repeat insertions or the formation of functional neotelomeres accompanied by terminal deletions. The threat that telomerase poses to genome integrity was minimized by ataxia telangiectasia and Rad3-related (ATR) kinase signaling, which inhibited telomerase at resected DSBs. In addition to acting at resected DSBs, telomerase used the extruded strand in the Cas9 enzyme-product complex as a primer for neotelomere formation. We propose that although neotelomere formation is detrimental in normal human cells, it may allow cancer cells to escape from breakage-fusion-bridge cycles.

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Maternal behaviours disrupted by Gprasp2 deletion modulate neurodevelopmental trajectory in progeny

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SCIENTIFIC REPORTS 2024年第1期14卷 1-15页

作者： Pereira, Marta I. Laranjo, Mariana Gomes, Marcos Edfawy, Mohamed Peca, Joao Univ Coimbra CNC Ctr Neurosci & Cell Biol P-3004504 Coimbra Portugal Univ Coimbra Fac Med PhDOC PhD Program CIBB Coimbra Portugal Univ Coimbra IIIUC Inst Interdisciplinary Res P-3030789 Coimbra Portugal Univ Coimbra PhD Program Expt Biol & Biomed PDBEB Coimbra Portugal HEMEX AG Liestal Switzerland Univ Coimbra Dept Life Sci P-3000456 Coimbra Portugal

Autism spectrum disorders (ASDs) are known to present sex-specific differences. At the same time, understanding how maternal behaviours are affected by pathogenic mutations is crucial to translate research efforts since rearing may recursively modulate neurodevelopment phenotype of the progeny. In this work, we focused on the effects of Gprasp2 deletion in females and its impact in progeny care and development. Female mice, wild-type (WT), Gprasp2 +/- (HET) or Gprasp2 -/- (KO) mutants and their progeny were used and behavioural paradigms targeting anxiety, memory, maternal care, and other social behaviours were performed. Analysis of communication was carried out through daily recordings of ultrasonic vocalizations in isolated pups and cross-fostering experiments were performed to understand the effect of maternal genotype in pup development. We found that Gprasp2 -/- females presented striking impairments in social and working memory. Females also showed disruptions in maternal care, as well as physiological and molecular alterations in the reproductive system and hypothalamus, such as the structure of the mammary gland and the expression levels of oxytocin receptor (OxtR) in nulliparous versus primiparous females. We observed alterations in pup communication, particularly a reduced number of calls in Gprasp2 KO pups, which resulted from an interaction effect of the dam and pup genotype. Cross-fostering mutant pups with wild-type dams rescued some of the early defects shown in vocalizations, however, this effect was not bidirectional, as rearing WT pups with Gprasp2 -/- dams was not sufficient to induce significant phenotypical alterations. Our results suggest Gprasp2 mutations perturb social and working memory in a sex-independent manner, but impact female-specific behaviours towards progeny care, female physiology, and gene expression. These changes in mutant dams contribute to a disruption in early stages of progeny development. More generally, our results highl

关键词： GPRASP2 Autism Maternal care Ultrasonic vocalisations Oxytocin receptor Sex differences Cross fostering

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Eukaryotic initiation factor 4F promotes a reorientation of eukaryotic initiation factor 3 binding on the 5′ and the 3′ UTRs of barley yellow dwarf virus mRNA

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NUCLEIC ACIDS RESEARCH 2022年第9期50卷 4988-4999页

作者： Powell, Paul Bhardwaj, Usha Goss, Dixie CUNY Dept Chem Hunter Coll New York NY 10065 USA CUNY PhD Program Chem Grad Ctr New York NY 10016 USA CUNY Grad Ctr PhD Program Biochem New York NY 10016 USA

Viral mRNAs that lack a 5 ' m(7)GTP cap and a 3 ' poly-A tail rely on structural elements in their untranslated regions (UTRs) to form unique RNA-protein complexes that regulate viral translation. Recent studies of the barley yellow dwarf virus (BYDV) have revealed eukaryotic initiation factor 3 (eIF3) plays a significant role in facilitating communication between its 5 ' and 3 ' UTRs by binding both UTRs simultaneously. This report uses in vitro translation assays, fluorescence anisotropy binding assays, and selective 2 '-hydroxyl acylation analyzed by primer extension (SHAPE) footprinting to identify secondary structures that are selectively interacting with eIF3. SHAPE data also show that eIF3 alters its interaction with BYDV structures when another factor crucial for BYDV translation, eIF4F, is introduced by the 3 ' BYDV translational enhancer (BTE). The observed BTE and eIF4F-induced shift of eIF3 position on the 5' UTR and the translational effects of altering eIF3-binding structures (SLC and SLII) support a new model for BYDV translation initiation that requires the reorientation of eIF3 on BYDV UTRs. This eIF3 function in BYDV translation initiation is both reminiscent of and distinct from eIF3-RNA interactions found in other non-canonically translating mRNAs (e.g. HCV). This characterization of a new role in translation initiation expands the known functionality of eIF3 and may be broadly applicable to other non-canonically translating mRNAs.

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Isolation and characterization of Clostridium tertium IGP01 as newly isolated hydrogen-producing bacteria with enhancement via biochar and magnetic nanoparticle supplementation

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BIORESOURCE TECHNOLOGY 2025年 422卷 132214页

作者： Kriswantoro, Jayen Aris Chu, Chen-Yeon Feng Chia Univ PhD Program Mech & Aeronaut Engn Taichung 407 Taiwan Feng Chia Univ Inst Green Prod Taichung 407 Taiwan Inst Teknol Bandung Sch Life Sci & Technol Bandung 40132 Indonesia

Clostridium spp. holds significant potential hydrogen-producing bacteria for biohydrogen production which can be used to treat a wide range of carbon sources, including biomass waste. Previous studies have given considerable attention to C. acetobutylicum, C. beijerinckii, and C. butyricum, which have efficiently converted sugar into biohydrogen. This study aims to isolate the potent Clostridia genera and investigate optimal conditions for cell growth and volatile fatty acids production, such as temperature, initial pH, and medium compositions. This study also examined the effect of different biochar (10 g/L), magnetite (magnetic nanoparticles, 100 mg/L), and magnetic fields on biohydrogen production performances. The results revealed that Clostridium tertium IGP01 was isolated with optimal growth conditions when sucrose was utilized as a carbon source with an organic nitrogen source at 37 degrees C with an initial pH of 5.5. In this condition, C. tertium IGP01 achieves the highest biohydrogen production yield of 4.21 f 0.19 mmol H2/mmol sucrose, 71.7 f 0.06 % hydrogen content, and production rate of 1.08 f 0.05 L/*** after 19 h incubation. Biochar addition enhanced biohydrogen production by 31.6-35.8 %, while the magnetite and magnetic field also improved by 11.7 % and 18.7 %, respectively. The butyric (2,844.5 f 4.3 mg/L) and acetic acids (1,383.4 f 1.9 mg/L) were observed as dominant volatile fatty acids (VFAS) produced as by-products after fermentation for 24 h. As the first study on C. tertium IGP01 in a single culture for biohydrogen production, these findings highlight the potential of C. tertium IGP01 and provide critical insight for dark fermentation control conditions.

关键词： Biohydrogen Biochar Clostridium tertium Dark fermentation Enhancement Nanoparticles

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From structural polymorphism to structural metamorphosis of the coat protein of flexuous filamentous potato virus Y

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COMMUNICATIONS CHEMISTRY 2024年第1期7卷 14页

作者： Kavcic, Luka Kezar, Andreja Koritnik, Neza Znidaric, Magda Tusek Klobucar, Tajda Vicic, Ziga Merzel, Franci Holden, Ellie Benesch, Justin L. P. Podobnik, Marjetka Natl Inst Chem Dept Mol Biol & Nanobiotechnol Ljubljana Slovenia Univ Ljubljana Fac Chem & Chem Technol PhD ProgramChem Sci Ljubljana Slovenia Univ Ljubljana Fac Med Dept Oncol PhD Program Biomed Ljubljana Slovenia Natl Inst Biol Dept Biotechnol & Syst Biol Ljubljana Slovenia Univ Ljubljana Biotech Fac Dept Biol PhD Program Biosci Ljubljana Slovenia Natl Inst Chem Theory Dept Ljubljana Slovenia Univ Oxford Dept Chem Oxford England Univ Oxford Kavli Inst Nanosci Discovery Oxford England

The structural diversity and tunability of the capsid proteins (CPs) of various icosahedral and rod-shaped viruses have been well studied and exploited in the development of smart hybrid nanoparticles. However, the potential of CPs of the wide-spread flexuous filamentous plant viruses remains to be explored. Here, we show that we can control the shape, size, RNA encapsidation ability, symmetry, stability and surface functionalization of nanoparticles through structure-based design of CP from potato virus Y (PVY). We provide high-resolution insight into CP-based self-assemblies, ranging from large polymorphic or monomorphic filaments to smaller annular, cubic or spherical particles. Furthermore, we show that we can prevent CP self-assembly in bacteria by fusion with a cleavable protein, enabling controlled nanoparticle formation in vitro. Understanding the remarkable structural diversity of PVY CP not only provides possibilities for the production of biodegradable nanoparticles, but may also advance future studies of CP's polymorphism in a biological context. Capsid proteins (CPs) of various icosahedral and rod-shaped viruses exhibit structural diversity and tunability as well as application in smart hybrid nanoparticles, however, the potential of CPs of filamentous plant viruses remains underexplored. Here, the authors exploit the structure-based design of CP from potato virus Y to tune the shape, size, RNA encapsidation ability, symmetry, stability, and surface functionalization of nanoparticles.

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Enhancing biohydrogen production with isolated Clostridium tertium IGP01 from cacao pod husk and spent coffee ground using biochar, nanoparticles, magnetic field, and immobilization technology

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BIOMASS & BIOENERGY 2025年 196卷

作者： Kriswantoro, Jayen Aris Pomdaeng, Prakaidao Ko, Ting-Wu Chu, Chen-Yeon Feng Chia Univ PhD Program Mech & Aeronaut Engn Taichung 407 Taiwan Feng Chia Univ Inst Green Prod Taichung 407 Taiwan Feng Chia Univ Masters Program Green Energy Sci & Technol Taichung 407 Taiwan Inst Teknol Bandung Sch Life Sci & Technol Bandung 40132 Indonesia

The study aims to investigate the effects of biochar (10 g/L), nanoparticles (100 mg/L), immobilization techniques mixed with biochar and NPs (10 % w/v), and magnetic fields on biohydrogen production performance from cacao pod husk (CPH) and spent coffee ground (SCG) hydrolysate using newly isolated Clostridium tertium IGP01. Hydrothermal pretreatment of dried CPH and SCG powder was performed by adding 10 % w/v to 1 % v/v H2SO4 and then autoclaving at 130 degrees C for 1 h. The optimum temperature of 60 degrees C resulted in the formation of 53 % magnetite and 18 % hematite, which enhanced biohydrogen production yield by 20 % in sucrose-based media. In the dark fermentation with lignocellulosic biomass hydrolysate as a substrate, the addition of immobilized biochar and nanoparticles showed the highest enhancement in hydrogen concentration and production yield for both CPH and SCG by C. tertium IGP01. Yielded biohydrogen achieved 3.61 and 9.27 mmol H2 per gram substrate, individually. The production yield increased by more than twofold and was 76.4 +/- 4.3 % higher, respectively, compared to the control. Moreover, the increase in biohydrogen performance was accompanied by a reduction in 5-(hydroxymethyl) furfural (5-HMF), influenced by an increase in carbonyl (C=C), quinone (C=O), and hydroxyl (O-H) bond groups following immobilization. As the first study to explore the potential of Clostridium tertium IGP01 for biohydrogen production from CPH and SCG hydrolysates, this work highlights the incorporation of immobilization techniques with biochar and nanoparticles as a promising approach to enhance biohydrogen generation, leveraging the efficiency of the newly isolated hydrogen-producing bacteria.

关键词： Biochar Biohydrogen Clostridium tertium Immobilization Magnetic field Nanoparticles

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Toward Protecting 5G Sidelink Scheduling in C-V2X Against Intelligent DoS Attacks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2023年第11期22卷 7273-7286页

作者： Twardokus, Geoff Rahbari, Hanif Rochester Inst Technol Elect & Comp Engn PhD Program Rochester NY 14623 USA Rochester Inst Technol ESL Global Cybersecur Inst Rochester NY 14623 USA

5G Cellular Vehicle-to-Everything (5G C-V2X) is emerging as the globally dominant connected vehicle technology. One critical application of 5G C-V2X is the direct exchange of safety-critical messages between vehicles to prevent crashes and correspondingly reduce roadway injuries and fatalities. While current C-V2X security protocols concern only message payloads, we expose vulnerabilities in the physical-layer attributes and decentralized MAC-layer scheduling algorithm of 5G C-V2X by developing two stealthy denial-of-service (DoS) attacks to exploit them. These low-duty-cycle attacks dramatically degrade C-V2X availability, increasing the likelihood of prolonged travel times and even vehicle crashes. We further develop detection and mitigation techniques for each attack, in part by exploiting new C-V2X features of 3GPP Rel-17. We experimentally evaluate our attacks and countermeasures in a hardware testbed composed of USRPs and state-of-the-art C-V2X kits as well as through extensive network and roadway simulations, showing that within seconds of initiation our attacks can reduce a target's packet delivery ratio by 90% or that of the C-V2X channel to under 25%. We further evaluate our machine-learning detection and low-cost mitigation techniques, showing the latter completely thwart one attack and reduce the impact of the other by 80%, providing insight towards developing a more robust 5G C-V2X.

关键词： 5G mobile communication Vehicle-to-everything Sensors 3GPP Wireless communication Protocols Denial-of-service attack V2V security denial-of-service selective jamming resource scheduling 5G

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Discussion Activities in Asynchronous Online Learning: Motivating Adult Learners' Interactions

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JOURNAL OF CONTINUING HIGHER EDUCATION 2024年第1期72卷 84-103页

作者： Lin, Xi Sun, Qi East Carolina Univ Dept Interdisciplinary Profess Greenville NC 27858 USA Univ Tennessee Adult Learning PhD Program Knoxville TN USA

This quantitative study investigates the impact of four types of discussion activities on adult learners' asynchronous online interactions. Specifically, this study aims to understand how different discussion activities incorporated into online discussion boards motivate adult learners' online participation. The four discussion activities are video-based text discussion, student-generated problem-based case discussion, self-created meme discussion, and discussion through debate. Results show that all four discussion activities, to a great extent, help motivate adult learners to actively interact with learning content, the instructor, and peers in different ways. Significantly, our study shows that participants identified student-generated problem-based case discussion as the most effective and that the debate was the least effective among the four discussion activities. Results also indicate that the instructor plays a significant role in the design, instruction, and follow-up of discussion activities. This study provides insights into using multiple discussion activities in fully asynchronous online environments for adult learners' active learning.

关键词： Online discussion activities online interactions adult learners asynchronous online learning

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