Search Results (195)

Avian pathogenic Escherichia coli (APEC) poses a global threat to poultry health and public safety due to its high lethality, limited treatment options, and potential for zoonotic transmission via the food chain. However, long-term genomic surveillance remains limited, especially in countries like China where poultry farming is highly intensive. This study aimed to characterize the population structure, virulence traits, and antimicrobial resistance of 81 APEC isolates from diseased chickens collected over 16 years from Shandong and neighboring provinces in eastern China. The isolates were grouped into seven Clermont phylogroups, with A and B1 being dominant. MLST revealed 27 STs, and serotyping identified 29 O and 16 H antigens, showing high genetic diversity. The minor phylogroups (B2, C, D, E, G) encoded more virulence genes and had higher virulence-plasmid ColV carriage, with enrichment for iron-uptake, protectins, and extraintestinal toxins. In contrast, the dominant phylogroups A and B1 primarily carried adhesin and enterotoxin genes. Antimicrobial resistance was widespread: 76.5% of isolates were multidrug-resistant. The minor phylogroups exhibited higher tetracycline resistance (mediated by tet(A)), whereas the major phylogroups showed increased resistance to third- and fourth-generation cephalosporins (due to bla_CTX-M-type ESBL genes). These findings offer crucial data for APEC prevention and control, safeguarding the poultry industry and public health. Full article

Deterministic random bit generators (DRBG) play a crucial role in device security because they generate secret information cryptographic systems, e.g., secret keys and parameters. Thus, attacks on DRBGs can result in the exposure of important secret values, which can threaten the entire cryptographic system of the target Internet of Things (IoT) equipment and smart devices. In 2020, Meyer proposed a side-channel attack (SCA) method that recovers the output random bits by analyzing the power consumption traces of the NIST standard AES CTR DRBG. In addition, most algorithmic countermeasures against SCAs also utilize random numbers; thus, such vulnerabilities are more critical than other SCAs on cryptographic modules. Meyer’s attack recovers the secret random number in four stages of the attack using only the power traces, which the CTR DRBG processes in 256 blocks. We present an approach that employs a clustering algorithm to enhance Meyer’s attack. The proposed attack increases the attack success rate and recovers more information using a clustering attack in the first step. In addition, it improves the attack accuracy in the third and fourth steps using the information obtained from the clustering process. These results lead to the possibility of attacks at higher noise levels and increase the diversity of target devices for attacking the CTR DRBG. Experiments were conducted on an Atmel XMEGA128D4 processor to evaluate the effectiveness of the proposed attack method. We also introduced artificial noise into the power traces to compare the proposed attack’s performance at different noise levels. Our results demonstrate that the first step of the proposed attack achieves a higher success rate than Meyer’s attack at all noise levels. For example, at high noise levels, the difference in the success rates is up to 50%. In steps 3 and 4, an average performance improvement of 18.5% greater than Meyer’s proposed method is obtained. The proposed attack effectively extends the target to more noisy environments than previous attacks, thereby increasing the threat of SCA on CTR DRBGs. Full article

A plant species in a community often grows with some other plant species. While many studies have assessed interspecific interactions between two target plant species, few have considered the impacts of the other plant species (e.g., the third, fourth, and fifth plant species) on these interactions. To assess the impacts, we grew one seedling of each of the five herbaceous plant species that are common in China (Cynodon dactylon, Plantago asiatica, Taraxacum mongolicum, Nepeta cataria, and Leonurus japonicus) alone (no competition) or with one seedling of one, two, three, or four of the other species. The presence of a neighbor plant generally reduced the growth of the target species, suggesting that the interspecific relationships were mostly competitive. The presence of other neighbor species (the third, fourth, and fifth species) could alter the interspecific interactions between two target species, but such effects varied depending on both the identity of the target species and the identity of the other species. Additionally, the effects of the third species depended little on the presence of the fourth and fifth species. We conclude that interspecific interactions between two plant species are commonly regulated by the presence of other species, facilitating species coexistence. However, our findings do not support the idea that the impacts of the fourth and fifth species on interactions among three plant species are common. This study highlights the complex interactions among multiple plant species within a community and also the importance of including these high-order interactions when modelling community dynamics and species coexistence. Full article

Blocking anticyclones are important atmospheric phenomena generally associated with extreme weather (e.g., droughts and cold air surges). Blockings also constitute large-scale indicators of climate change. The study of blockings in the Southern Hemisphere (SH) has been traditionally carried out utilizing reanalysis products. This paper is aimed at presenting an updated, comprehensive climatology of blockings in the SH as extracted from the ERA5 and the NCEP/NCAR reanalysis datasets in the 1940–2022 and 1948–2022 periods, respectively. Blockings were located by means of a unidimensional index at 500 hPa. The results were stratified by season, longitude, region, persistence, and intensity, and the climatology from both datasets was compared. The primary location of blockings was close to the Date Line in every season. Additionally, depending on the season, up to fourth-rank maxima could be located. Generally, the secondary maxima were found in the south Atlantic; lower-order maxima were located in the south-eastern Pacific, west of South America, and in the south-western Indian Ocean east of South Africa. The most intense blockings were concentrated in the Pacific and in the south Atlantic in both datasets, and they were also located in the Indian Ocean, but in the ERA5 reanalysis only. The longest-lived blockings occurred in the south Pacific and in the south Atlantic during southern winter. Full article

Massive multiple input–multiple output (M-MIMO) is a promising and pivotal technology in contemporary wireless communication systems that can effectively enhance link reliability and data throughput, especially in uplink scenarios. Even so, the receiving end requires more computational complexity to reconstitute the signal. This problem has emerged in fourth-generation (4G) MIMO system; with the dramatic increase in demand for devices and data in beyond-5G (B5G) systems, this issue will become yet more obvious. To take into account both complexity and signal-revested capability at the receiver, this study uses the matrix iteration method to avoid the staggering amount of operations produced by the inverse matrix. Then, we propose a highly efficient multi-user detector (MUD) named hybrid SOR-based Chebyshev acceleration (CHSOR) for the uplink of M-MIMO orthogonal frequency-division multiplexing (OFDM) and universal filtered multi-carrier (UFMC) waveforms, which can be promoted to B5G developments. The proposed CHSOR scheme includes two stages: the first consists of successive over-relaxation (SOR) and modified successive over-relaxation (MSOR), combining the advantages of low complexity of both and generating a better initial transmission symbol, iteration matrix, and parameters for the next stage; sequentially, the second stage adopts the low-cost iterative Chebyshev acceleration method for performance refinement to obtain a lower bit error rate (BER). Under constrained evaluation settings, Section (Simulation Results and Discussion) presents the results of simulations performed in MATLAB version R2022a. Results show that the proposed detector can achieve a 91.624% improvement in BER performance compared with Chebyshev successive over-relaxation (CSOR). This is very near to the performance of the minimum mean square error (MMSE) detector and is achieved in only a few iterations. In summary, our proposed CHSOR scheme demonstrates fast convergence compared to previous works and as such possesses excellent BER and complexity performance, making it a competitive solution for uplink M-MIMO B5G systems. Full article

Since the Montreal Protocol (dated 1987), the reduction of the environmental impact has been one of the main goals in the HVAC sector, which has led to the replacement of widely used fluids with new environmentally friendly ones. Nevertheless, only new fluids with suitable heat transfer features can be used. The refrigerant mixture R449a, one of the fourth-generation refrigerants, was tested during flow boiling inside a horizontal smooth tube. The experiments were carried out at six different mass fluxes G ∈ [175;400] kg·m⁻²·s⁻¹ and four different bubble temperatures T_b ∈ [2.5;10] °C, while the nominal values for inlet and outlet quality were selected as x_Ti = 0.1 and x_To = 0.9, respectively. The results highlighted that, as the bubble temperature increases, it has an opposite effect on the pressure drop per unit length and the heat transfer coefficient: the former decreases while the latter grows. The comparison between experimental results and the correlations showed that the Zhang and Webb formula provides the best prediction of pressure drop, while the models provided by Bertsch yield the most reliable predictions for the heat transfer coefficient. Nevertheless, for both quantities, other correlations with similar performances are available. Full article

Non-small-cell lung cancer (NSCLC) represents the most common type of lung cancer. The majority of patients with lung cancer characterized by activating mutations in the epidermal growth factor receptor (EGFR), benefit from therapies entailing tyrosine kinase inhibitors (TKIs). In this regard, osimertinib, a third-generation EGFR TKI, has greatly improved the outcome for patients with EGFR-mutated lung cancer. The AURA and FLAURA trials displayed the superiority of the third-generation TKI in both first- and second-line settings, making it the drug of choice for treating patients with EGFR-mutated lung cancer. Unfortunately, the onset of resistance is almost inevitable. On-target mechanisms of resistance include new mutations (e.g., C797S) in the kinase domain of EGFR, while among the off-target mechanisms, amplification of MET or HER2, mutations in downstream signaling molecules, oncogenic fusions, and phenotypic changes (e.g., EMT) have been described. This review focuses on the strategies that are currently being investigated, in preclinical and clinical settings, to overcome resistance to osimertinib, including the use of fourth-generation TKIs, PROTACs, bispecific antibodies, and ADCs, as monotherapy and as part of combination therapies. Full article

Solar thermal energy is one of the most interesting sustainable solutions for decarbonizing the energy sector. Integrating solar collectors with other energy sources is common, as seen in domestic heating, where solar collectors are combined with common heaters to reduce fuel consumption (gasoline, electricity, gas, and biomass) and therefore, the energy cost. Similarly, this concept can be applied to nuclear energy, where the reduction in nuclear fuel consumption is very strategic for decreasing not only its cost but also the risk in handling, transportation, and storage (both the fuel and the nuclear waste as well). Nuclear energy, on the other hand, seems to be very useful in reducing the land occupation of concentrated solar power plants (CSPs) and helping a more constant production of electricity, both points being two important bottlenecks of CSP technologies. CSP and nuclear reactors, on the other hand, share common heating technologies and both can produce energy without CO₂ emissions. Solar and nuclear energy, especially with the advent of the fourth generation of small modular reactors (SMRs), present a compelling opportunity for sustainable electricity generation. In this work, we present a brief review of CSP technology, a brief review of SMR concepts and development, and a brief overview of the combination of these two technologies. The review shows that in general, combined SMR + CSP technologies offer several advantages in terms of a strong reduction in the solar field extension areas, improved dispatchability of energy, improved efficiency of the SMRs, and, in particular, lower nuclear fuel consumption (hence, e.g., with a lowered refueling frequency). Full article

The deployment of large installed power capacities from intermittent renewable energy sources requires balancing to ensure the steady and safe operation of the electrical grid. New methods of energy storage are essential to store excess electrical power when energy is not needed and later use it during high-demand periods, both in the short and long term. Power-to-Gas (P2G) is an energy storage solution that uses electric power produced from renewables to generate gas fuels, such as hydrogen, which can be stored for later use. Hydrogen produced in this manner can be utilized in energy storage systems and in transportation as fuel for cars, trams, trains, or buses. Currently, most hydrogen is produced from fossil fuels. Solid-oxide electrolysis (SOE) offers a method to produce clean hydrogen without harmful emissions, being the most efficient of all electrolysis methods. The objective of this work is to determine the optimal operational parameters of an SOE system, such as lower heating value (LHV)-based efficiency and total input power, based on calculations from a mathematical model. The results are provided for three different operating temperature levels and four different steam utilization ratios. The introductory chapter outlines the motivation and background of this work. The second chapter explains the basics of electrolysis and describes its different types. The third chapter focuses on solid-oxide electrolysis and electrolyzer systems. The fourth chapter details the methodology, including the mathematical formulations and software used for simulations. The fifth chapter presents the results of the calculations with conclusions. The final chapter summarizes this work. Full article

This paper proposes a system made up of four subsystems connected in sequence. The first and third subsystems each have one unit, the second has two, and the fourth has three. Every subsystem operates in parallel and is governed by the K-Out-of-n:G rule. Nonetheless, each subsystem needs at least one operational unit in order for the system to work. While a unit’s failure has an exponential distribution, repair is simulated using a general distribution and a distribution from the Gumbel–Hougaard family of copula. This study’s primary objective is to assess and contrast the system performance while our system is running under these two different repair policies. The problem is solved by combining the supplementary variable technique with Laplace transforms. We use reliability metrics to assess system performance. The second objective of this study is to present a reduction approach plan aimed at improving the overall reliability metrics of our system. Full article

Reducing agricultural waste through reuse has become one of the most important strategies to minimise impact on the environment—an emerging global issue. Sunflower ranks fourth in the world in the production of vegetable oilseeds and therefore generates large amounts of agricultural waste. The aim of this study was to investigate the phytochemical composition and bioactivity of sunflower crop residues in order to open up new opportunities for waste management. TPC and TFC were determined spectrophotometrically, while the dominant compounds were identified by LC-DAD-ESI-MS as ent-kaur-16-en-19-oic acid (KA) and 6Ac-7OH-dimethylchromone (DMC). Both compounds were present in higher concentrations in the ethyl acetate fraction (245.5 and 16.8 mg/g, respectively) than in the ethanol extract. None of the tested samples showed antimicrobial effects in the microdilution test. DMC showed remarkable antioxidant activity by DPPH, ABTS, FRAP and TRC in vitro assays, while both compounds proved to be promising enzyme inhibitory agents, being particularly efficient in inhibiting anti-neurodegenerative enzymes (IC₅₀ values of DMC and KA were 1.20/1.37 mg/mL and 1.44/1.63 mg/mL for AChE/BChE, respectively) and tyrosinase. The results presented indicate that sunflower crop residues are a good candidate for the extraction of bioactive compounds with potential application in the food, pharmaceutical and cosmetic industries. Full article

The aim of this study was to investigate the usefulness of human embryonic kidney HEK293 cells as a model of normal cells in biotin-mediated therapy. The expression and role of sodium multivitamin transporter (SMVT) in the uptake and accumulation of free biotin, as well as cationic and neutral biotinylated PAMAM dendrimers of the fourth generation synthesized in our laboratory, were assessed in HEK293 cells in comparison to other immortalized (HaCaT) and cancer cells (HepG2, U-118 MG). The obtained data showed that a higher level of SMVT in HEK293 cells was not associated with a stronger uptake of biotin and biotinylated PAMAM dendrimers. Biotinylation increased the selective uptake of neutral dendrimers in an inversely proportional manner to the concentration used; however, the accumulation in HEK293 cells was lower than that in cells of other cell lines. The time-dependent biotin and biotinylated dendrimers uptake profiles differed significantly. Therefore, it should be assumed that the efficiency of biotinylated nanoparticles’ uptake depends on multiple cellular transport mechanisms. Toxicity tests showed significantly higher sensitivity to PAMAM conjugates for HEK293 cells than for HepG2 and HaCaT cells. Molecular modeling studies and the profile of biotin uptake suggest that not only SMVT but also monocarboxylate transporter 1 (MCT-1) may play an important role in the selective transport of biotin and biotinylated nanoparticles into cells. Due to the complexity of the problem, further studies are necessary. In summary, HEK293 cells can be considered a valuable model of normal cells in the study of biotin- targeted therapy using nanoparticles based on PAMAM dendrimers. Full article

5G, the fifth-generation mobile network, is predicted to significantly increase the traditional trajectory of energy consumption. It now uses four times as much energy as 4G, the fourth-generation mobile network. As a result, compared to previous generations, 5G’s increased cell density makes energy efficiency a top priority. The objective of this paper is to formulate end-to-end power consumption models for three different 5G radio access network (RAN) deployment architectures, namely the 5G distributed RAN, the 5G centralized RAN with dedicated hardware and the 5G Cloud Centralized-RAN. The end-to-end modelling of the power consumption of a complete 5G system is obtained by combining the power models of individual components such as the base station, the core network, front-haul, mid-haul and backhaul links, as applicable for the different architectures. The authors considered the deployment of software-defined networking (SDN) at the 5G Core network and gigabit passive optical network as access technology for the backhaul network. This study examines the end-to-end power consumption of 5G networks across various architectures, focusing on key dependent parameters. The findings indicate that the 5G distributed RAN scenario has the highest power consumption among the three models evaluated. In comparison, the centralized 5G and 5G Cloud C-RAN scenarios consume 12% and 20% less power, respectively, than the Centralized RAN solution. Additionally, calculations reveal that base stations account for 74% to 78% of the total power consumption in 5G networks. These insights helped pioneer the calculation of the end-to-end power requirements of different 5G network architectures, forming a solid foundation for their sustainable implementation. Furthermore, this study lays the groundwork for extending power modeling to future 6G networks. Full article

Agricultural sustainability is becoming more and more important for human health. Wireless sensing technology could provide smart monitoring in real time for different parameters in planting, breeding, and the food supply chain with advanced sensors such as flexible sensors; wireless communication networks such as third-, fourth-, or fifth-generation (3G, 4G, or 5G) mobile communication technology networks; and artificial intelligence (AI) models. Many sustainable, natural, renewable, and recycled facility energies such as light, wind, water, heat, acoustic, radio frequency (RF), and microbe energies that exist in actual agricultural systems could be harvested by advanced self-powered technologies and devices using solar cells, electromagnetic generators (EMGs), thermoelectric generators (TEGs), piezoelectric generators (PZGs), triboelectric nanogenerators (TENGs), or microbial full cells (MFCs). Sustainable energy harvesting to the maximum extent possible could lead to the creation of sustainable self-powered wireless sensing devices, reduce carbon emissions, and result in the implementation of precision smart monitoring, management, and decision making for agricultural production. Therefore, this article suggests that proposing and developing a self-powered wireless sensing system for sustainable agriculture (SAS) would be an effective way to improve smart agriculture production efficiency while achieving green and sustainable agriculture and, finally, ensuring food quality and safety and human health. Full article

This paper presents a novel double-sided structure multi-band antenna that cleverly combines a Koch snowflake structure with a hexagonal fractal structure; the front of the antenna features a right semicircle minus a half-order Koch snowflake structure, while the back of the antenna showcases a left semicircle minus half of a hexagonal fractal snowflake structure, which are combined together to form a complete circle. The antenna can cover common communication bands such as fourth to fifth generation (5G) commercial bands, ISM, WLAN, and Bluetooth. The structure of the radiator portion of the antenna is designed by iteratively scaling a basic arc shape multiple times based on a certain scale factor, and after simulation and comparison, three iterations can achieve the best antenna performance, and the antenna uses a microstrip line transmission to broaden the antenna bandwidth. The antenna covers three effective frequency bands: 2.38–2.90 GHz (20.3%), 3.35–3.85 GHz (14.1%), and 5.06–5.80 GHz (13.5%). The antenna dielectric sheet is made of RF-35 from Taconic, which has the advantages of high strength, complete surface inertness, and a long service life, with a dielectric constant of 3.5 and actual dimensions of 50 mm × 54 mm × 0.76 mm. The antenna is fractal-iterated in small dimensions, and the approximation of the frequency bands is accomplished by comparing the ratios of each iteration with the current vector map. The antenna was simulated by HFSS software (Version 21). and measured in an electromagnetic anechoic chamber, and the test results were consistent with the simulation results. Full article