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Sisyrinchium micranthum (Iridaceae, Iridoideae, Sisyrinchieae) in Tunisia, a first record for the African continent
Get PDFThis study reports the first discovery of Sisyrinchium micranthum in Tunisia, marking the species' inaugural record on the African mainland and along the southern Mediterranean coast. The paper provides a concise morphological description of the species, an account of its phenology, and detailed information on its distribution, habitat, and ecological context in Tunisia. Additionally, we present original photographs of this diminutive annual species. An updated key to the diversity of the Iridaceae family in North Africa is also included
TEŠKI METALI U POVRŠINSKIM SEDIMENTIMA JEZERA BATUR, BALI, INDONEZIJA: PROSTORNA RAZDIOBA, PROCJENA RIZIKA I RASPODJELA IZVORA
No full textThis study aims to assess the environmental conditions of Lake Batur, Indonesia, a closed alkaline lake. In this study, the identification of heavy metals was carried out using 27 sediment and 13 water samples. The methods used in the study include magnetic susceptibility, geochemical, and multivariate analysis. The concentration of heavy metals in sediment samples follows the order Fe > Ti > Mn > V > Cu > Cr (wt%). The results of the pollution assessment (EF, Igeo, CF, and PLI) in sediment indicate that the lake sediment is currently polluted. The PLI shows that the Lake Batur sediment is in the high contamination category at all sample sites, especially because of the high enrichment of Cu and Cr. The use of metal (kepeng) in religious activities in temples near Lake Batur is believed to be the source of the Cu enrichment. The results of multivariate analysis and magnetic susceptibility reveal three groups of heavy metals in Lake Batur sediment based on their main sources: 1) Fe and Ti are dominated by lithogenic factors, 2) Cu and Cr are dominated by anthropogenic factors, and 3) Mn and V are influenced by a combination of lithogenic and anthropogenic factors. The heavy metal concentrations in water samples are as follows: Zn > Fe > Mn > As > Cu > Cr > Pb > Cd (ppb). Water samples show that heavy metal concentrations are still below the WHO's minimum drinking water threshold.Cilj je ovoga istraživanja procijeniti uvjete okoliša jezera Batur, Indonezija, zatvorenoga alkalnog jezera. U istraživanju ie identifikacija teških metala provedena korištenjem 27 uzoraka sedimenta i 13 uzoraka vode. Metode korištene u studiji uključuju magnetnu osjetljivost, geokemijsku i multivarijantnu analizu. Koncentracija teških metala u uzorcima sedimenta slijedi redoslijed Fe > Ti > Mn > V > Cu > Cr (wt%). Rezultati procjene onečišćenja (EF, Igeo, CF i PLI) u sedimentu upućuju na to da je jezerski sediment trenutačno onečišćen. PLI pokazuje da je sediment jezera Batur u kategoriji visoke kontaminacije na svim mjestima uzorkovanja, posebno zbog visokoga obogaćivanja bakra i kroma (Cu i Cr). Vjeruje se da je uporaba metala (kepeng) u vjerskim aktivnostima u hramovima u blizini jezera Batur izvor obogaćivanja bakra (Cu). Rezultati multivarijantne analize i magnetne osjetljivosti otkrivaju tri skupine teških metala u sedimentu jezera Batur na temelju njihovih glavnih izvora: 1) željezom i titanom (Fe i Ti) dominiraju litogeni čimbenici, 2) bakrom i kromom (Cu i Cr) dominiraju antropogeni čimbenici, 3) mangan i vanadij (Mn i V) pod utjecajem su kombinacije litogenih i antropogenih čimbenika. Koncentracije su teških metala u uzorcima vode sljedeće: Zn > Fe > Mn > As > Cu > Cr > Pb > Cd (ppb). Uzorci vode pokazuju da su koncentracije teških metala još uvijek ispod minimalnoga praga za pitku vodu Svjetske zdravstvene organizacije (WHO)
Remarks on Acalypha rhomboidea in Europe, with a fifth record at the continental level
Get PDFAcalypha is a genus native to tropical and subtropical regions of the world and eastern North America and Asia, with some species considered as aliens in Eurasia. The European flora is reported to include four species, all occurring in Italy according to Plant of the World Online database. As part of the ongoing studies of the flora of Treviso Province (Veneto region, north-eastern Italy), we came across to a population of A. rhomboidea Raf. which represents not only the first record for Veneto and the second one for the Italian flora, but also the fifth discovery of the species out of its native range; a description of the species (the first one for Italy), ecological remarks, and a map of the European occurrences are provided
Leveraging Word2Vec-Enhanced CNN-LSTM Hybrid Architecture for Sentiment Analysis in E-Commerce Product Reviews
No full textThe amalgamation of machine learning (ML) techniques and natural language processing (NLP) is leveraged to evaluate the sentiment of textual input. With the increasing popularity of e-commerce platforms like Amazon, product reviews have emerged as an essential source of information for potential purchasers, providing insights into product quality and performance from the consumers' viewpoints. This study aims to systematically organize and analyze customer opinions to effectively capture consumer sentiment based on product reviews. In this study, we propose a deep learning framework that combines a stacked 1D convolutional layer (CNN) with a Long Short-Term Memory (LSTM) network, using pre-trained Word2Vec embedding as fixed input representations. Evaluated on a large Amazon product review dataset, our model — StackedCNN-LSTM-W2V — achieves a classification accuracy of 99%, outperforming traditional CNN, LSTM, and logistic regression baselines
Use of BeeSmoke smoker pellets during the active beekeeping season
No full textAn innovative and sustainable approach to beekeeping involves using commercially available pellet fuels, such as BeeSmoke Forte or BeeSmoke, for daily work in the apiary. This study aimed to determine the effectiveness of these pellets, including their impacts on the strength and behaviour of honeybee colonies, their ability to reduce the number of parasitic mites Varroa destructor, and the presence of insecticide/acaricide residues in honey. During the study, the smoke produced by burning BeeSmoke Forte, BeeSmoke, and pure wood pellets in a smoker caused no changes to honeybee behaviour and resulted in no fatalities. BeeSmoke Forte and BeeSmoke pellets increased the number of fallen parasitic mites V. destructor. Furthermore, honey collected before and after the use of pellets and analysed for the presence of insecticide/acaricide residues gave negative results, indicating that the honey extracted during the active beekeeping season when these fuels were used is safe for bees and for human consumption
Influence of Corporate Citizenship on Retail Consumers' Planned Behavior
No full textThis study investigates the impact of Corporate Citizenship on consumer behavior in Colombia's retail sector following the COVID-19 pandemic. It examines how corporate actions influence customer attitudes, purchase intentions, and behaviors. An online survey was conducted among working individuals in the retail sector residing in Bogota and Medellin, analyzing 221 responses. Corporate Citizenship was measured using the Maignan and Ferrell (2000) scale, while consumer behavioral aspects were assessed via constructs from Ajzen's Theory of Planned Behavior. The study utilized a structural equation modeling approach. The research identifies a significant positive relationship between corporate actions, attitudes toward behavior, subjective norms, and perceived behavioral control on buying intention. These findings underscore the broad influence of corporate behavior on consumer choices, highlighting its strategic value in enhancing customer relations and societal impact, especially during disruptive events like the pandemic. This study emphasizes the pivotal role of corporate behavior in shaping consumer decisions and influencing attitudes and purchasing intentions in the retail sector. It stresses the importance of inclusive cultural dialogues and transparent practices to uphold democratic and sustainable values in business operations. From a managerial perspective, the findings underscore the importance of integrating corporate citizenship practices into retail strategies to foster positive consumer attitudes, enhance perceived behavioral control, and align with societal norms, thereby boosting customer loyalty and driving sustainable business growth
Hybrid Relaying Cooperative NOMA with Adaptive and Opportunistic Resource Allocation for Downlink Optimization in B5G Networks
No full textThis research investigates the optimization of downlink performance metrics, including spectral efficiency, data rates, and coverage, for cell-edge user equipment (UE) in Beyond 5G (B5G) networks using a hybrid relaying Cooperative Non-Orthogonal Multiple Access (CNOMA) framework. The system architecture consists of a gNodeB (gNB) located at the cell center, serving both an intra-cell cluster (ICC) near the gNB and a cell-edge cluster (CEC) positioned farther away. To address the challenges faced by UEs in these clusters, particularly random signal strength deprivation due to deep Rayleigh fading, two novel resource allocation strategies are proposed: Channel-Aware Adaptive Fair (CAAF) Power Allocation and Resource-Free Best Positioned Opportunistic Relay Selection (RFBP-ORS). The CAAF method ensures fair and dynamic power allocation by leveraging real-time channel state information (CSI), while RFBP-ORS selects the optimal relay based on resource availability and spatial positioning, thereby maintaining uninterrupted connectivity. Simulation results reveal that the proposed methodologies significantly enhance the achievable data rates by up to 140% compared to conventional CNOMA, reaching 5.8 bps/Hz at 12.5 dB SINR. They also improve energy efficiency to 1 Gb/J and achieve a 10 times reduction in outage probability for cell-edge users at 12.5 dB SINR, thereby demonstrating strong suitability for B5G deployment requirements. The proposed CNOMA-based hybrid relaying scheme outperforms conventional resource allocation approaches, offering a reliable and efficient communication framework for B5G networks, particularly benefiting UEs near the cell edge. These findings underline the potential of CNOMA-based adaptive and opportunistic resource allocation in addressing the evolving demands of next-generation wireless networks
Integration of Improved Whale Optimization Algorithm and Deep Learning for Trust Management in Social IoT Environment
No full textThe Social Internet of Things (SIoT) integrates IoT with social networks, enabling autonomous device interactions and seamless data sharing. A key challenge in SIoT is ensuring secure and reliable interactions through an effective Trust Management System (TMS). This paper proposes the Integration of Improved Whale Optimization Algorithm and Deep Learning for Trust Management System (IIWOADL-TMS) to enhance trust evaluation and authentication in SIoT environments. The model computes direct and indirect trust values to assess device credibility, restricting access to untrusted nodes. It employs Long Short-Term Memory (LSTM) networks for traffic classification and dynamically determines the Threshold Trust Value (THVL) to enhance security. The Improved Whale Optimization Algorithm (IWOA) optimizes LSTM's hyperparameters, improving classification accuracy and trust assessment efficiency. Experimental evaluations demonstrate that IIWOADL-TMS outperforms existing models in trust evaluation, authentication, and secure data communication. The proposed system enhances reliability, scalability, and resilience in SIoT networks by mitigating security risks and improving trust computation mechanisms. These results highlight IIWOADL-TMS as a robust solution for secure and efficient interactions in SIoT
Real-time continuous monitoring: A new paradigm for transformer asset management
Get PDFA major utility in the Caribbean discovered a fatal flaw in a transformer before it caused a costly incident. A hydrogen sensor recently installed on the transformer detected the presence of hydrogen gas in the insulating fluid. Crews were able to remove the transformer from service before a failure occurred. The article explains hydrogen sensor technology, discusses transformer reliability, and compares continuous monitoring to time-based maintenance
