bluuebunny/crossref_metadata_2025 huggingface dataset:
Eco-Friendly Catalytic Synthesis of Top Value Chemicals from Valorization of Cellulose Waste
Authors: Losito Onofrio , Casiello Michele , Fusco Caterina , Mateos Cuadrado Helena , Monopoli Antonio , Nacci Angelo , D’Accolti Lucia
Published: March 2023

The total amount of cellulose from paper, wood, food, and other human activity waste produced in the EU is in the order of 900 million tons per year. This resource represents a sizable opportunity to produce renewable chemicals and energy. This paper reports, unprecedently in the literature, the usage of four different urban wastes such as cigarette butts, sanitary pant diapers, newspapers, and soybean peels as cellulose fonts to produce valuable industrial intermediates such as levulinic acid (LA), 5-acetoxymethyl-2-furaldehyde (AMF), 5-(hydroxymethyl)furfural (HMF), and furfural. The process is accomplished by the hydrothermal treatment of cellulosic waste using both Brønsted and Lewis acid catalysts such as CH3COOH (2.5–5.7 M), H3PO4 (15%), and Sc(OTf)3 (20% w:w), thus obtaining HMF (22%), AMF (38%), LA (25–46%), and furfural (22%) with good selectivity and under relatively mild conditions (T = 200 °C, time = 2 h). These final products can be employed in several chemical sectors, for example, as solvents, fuels, and for new materials as a monomer precursor. The characterization of matrices was accomplished by FTIR and LCSM analyses, demonstrating the influence of morphology on reactivity. The low e-factor values and the easy scale up render this protocol suitable for industrial applications.
Carboxymethyl Cellulose/Copper Oxide–Titanium Oxide Based Nanocatalyst Beads for the Reduction of Organic and Inorganic Pollutants
Authors: Bakhsh Esraa M. , Khan Sher Bahadar , Maslamani Nujud , Danish Ekram Y. , Akhtar Kalsoom , Asiri Abdullah M.
Published: March 2023

In this work, we have developed novel beads based on carboxymethyl cellulose (CMC) encapsulated copper oxide-titanium oxide (CuO-TiO2) nanocomposite (CMC/CuO-TiO2) via Al+3 cross-linking agent. The developed CMC/CuO-TiO2 beads were applied as a promising catalyst for the catalytic reduction of organic and inorganic contaminants; nitrophenols (NP), methyl orange (MO), eosin yellow (EY) and potassium hexacyanoferrate (K3[Fe(CN)6]) in the presence of reducing agent (NaBH4). CMC/CuO-TiO2 nanocatalyst beads exhibited excellent catalytic activity in the reduction of all selected pollutants (4-NP, 2-NP, 2,6-DNP, MO, EY and K3[Fe(CN)6]). Further, the catalytic activity of beads was optimized toward 4-nitrophenol with varying its concentrations and testing different concentrations of NaBH4. Beads stability, reusability, and loss in catalytic activity were investigated using the recyclability method, in which the CMC/CuO-TiO2 nanocomposite beads were tested several times for the reduction of 4-NP. As a result, the designed CMC/CuO-TiO2 nanocomposite beads are strong, stable, and their catalytic activity has been proven.
In Vitro Characterizations of Post-Crosslinked Gelatin-Based Microspheres Modified by Phosphatidylcholine or Diammonium Phosphate as Antibiotic Delivery Vehicles
Authors: Chang Kai-Chi , Chang Pei-Jheng , Chen Jian-Chih , Huang Ssu-Meng , Liu Shih-Ming , Shih Chi-Jen , Chen Wen-Cheng
Published: March 2023

Hydrogel-based microspheres prepared by emulsification have been widely used as drug carriers, but biocompatibility remains a challenging issue. In this study, gelatin was used as the water phase, paraffin oil was used as the oil phase, and Span 80 was used as the surfactant. Microspheres were prepared using a water-in-oil (W/O) emulsification. Diammonium phosphate (DAP) or phosphatidylcholine (PC) were further used to improve the biocompatibility of post-crosslinked gelatin microspheres. The biocompatibility of DAP-modified microspheres (0.5–10 wt.%) was better than that of PC (5 wt.%). The microspheres soaked in phosphate-buffered saline (PBS) lasted up to 26 days before fully degrading. Based on microscopic observation, the microspheres were all spherical and hollow inside. The particle size distribution ranged from 19 μm to 22 μm in diameter. The drug release analysis showed that the antibiotic gentamicin loaded on the microspheres was released in a large amount within 2 h of soaking in PBS. It was stabilized until the amount of microspheres integrated was significantly reduced after soaking for 16 days and then released again to form a two-stage drug release curve. In vitro experiments showed that DAP-modified microspheres at concentrations less than 5 wt.% had no cytotoxicity. Antibiotic-impregnated and DAP-modified microspheres had good antibacterial effects against Staphylococcus aureus and Escherichia coli, but these drug-impregnated groups hinder the biocompatibility of hydrogel microspheres. The developed drug carrier can be combined with other biomaterial matrices to form a composite for delivering drugs directly to the affected area in the future to achieve local therapeutic effects and improve the bioavailability of drugs.
Enhancing the Photovoltaic Properties via Incorporation of Selenophene Units in Organic Chromophores with A2-π2-A1-π1-A2 Configuration: A DFT-Based Exploration
Authors: Arshad Muhammad Nadeem , Shafiq Iqra , Khalid Muhammad , Asad Mohammad , Asiri Abdullah M. , Alotaibi Maha M. , Braga Ataualpa A. C. , Khan Anish , Alamry Khalid A.
Published: March 2023

Currently, polymer organic solar cells (POSCs) are widely utilized due to their significant application, such as low-cost power conversion efficiencies (PCEs). Therefore, we designed a series of photovoltaic materials (D1, D2, D3, D5 and D7) by the incorporation of selenophene units (n = 1–7) as π1-spacers by considering the importance of POSCs. Density functional theory (DFT) calculations were accomplished at MPW1PW91/6-311G (d, p) functional to explore the impact of additional selenophene units on the photovoltaic behavior of the above-mentioned compounds. A comparative analysis was conducted for designed compounds and reference compounds (D1). Reduction in energy gaps (∆E = 2.399 − 2.064 eV) with broader absorption wavelength (λmax = 655.480 − 728.376 nm) in chloroform along with larger charge transference rate was studied with the addition of selenophene units as compared to D1. A significantly higher exciton dissociation rate was studied as lower values of binding energy (Eb = 0.508 − 0.362 eV) were noted in derivatives than in the reference (Eb = 0.526 eV). Moreover, transition density matrix (TDM) and density of state (DOS) data also supported the efficient charge transition origination from HOMOs to LUMOs. Open circuit voltage (Voc) was also calculated for all the aforesaid compounds to check the efficiency, and significant results were seen (1.633–1.549 V). All the analyses supported our compounds as efficient POSCs materials with significant efficacy. These compounds might encourage the experimental researchers to synthesize them due to proficient photovoltaic materials.
Emission of Volatile Organic Compounds in Crumb Rubber Modified Bitumen and Its Inhibition by Using Montmorillonite Nanoclay
Authors: Liu Gang , Fang Shuaiyin , Wang Yong , Liu Jinjun , Liang Yangshi , Cao Tingwei , Liu Quantao
Published: March 2023

Bitumen emits a large amount of volatile organic compounds (VOCs) during the production and construction of asphalt mixture, which can cause both environmental hazards and health risks. In this study, a setup was designed to collect the VOCs released by base and crumb rubber-modified bitumen (CRMB) binders and their composition was characterized by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Next, organic montmorillonite (Mt) nanoclay was added into CRMB binder and its inhibiting effect on the VOCs emission of the binder was investigated. Finally, the VOCs emission models for the CRMB and Mt-modified CRMB (Mt-CRMB) binders were established according to reasonable assumptions. The results indicated that the VOCs emission of CRMB binder was 3.2 times larger than that of the base binder. Due to its intercalated structure, the nanoclay can reduce the VOCs emission of CRMB binder by 30.6%. Especially, its inhibition effects on alkanes, olefins, and aromatic hydrocarbons were more significant. After finite element verification, the established model based on the Fick’s second law can describe the emission behavior of CRMB and Mt-CRMB binders well. Overall, the Mt nanoclay can be used as an effective modifier to inhibit the VOCs emission of CRMB binder.
Can Different Parameter Sets Lead to Equivalent Optima between Geometric Accuracy and Mechanical Properties in Arburg Plastic Freeforming?
Authors: Eisele Lars , Heuer Anselm , Weidenmann Kay A. , Liebig Wilfried V.
Published: March 2023

Technological advances have led to the increased use of plastic-based additive manufacturing processes for the production of consumer goods and spare parts. For this reason, the need for the best possible mechanical properties while maintaining geometric accuracy is becoming increasingly important. One of these additive manufacturing processes is the Arburg Plastic Freeforming process, which differs from the widely used Fused Filament Fabrication process in the way that droplets are discharged along a track instead of continuous extruded tracks. As with all other plastic-based additive manufacturing processes, due to the round shape of the tracks, voids occur between the individual tracks during manufacturing, which effects mechanical properties. In contrast to previous work, which mainly focused on how the mechanical properties change with a change in a single printing parameter, this work focused more closely on the interaction of three relevant printing parameters considered as a parameter set. Their influence on the mechanical properties was investigated by tensile tests, the influence on the residual porosity by density measurements and the influence on the geometric accuracy by surface roughness measurements. It was shown that by considering the parameters as a parameter set, states of high density and therefore high mechanical properties while reaching minimal surface roughness can be achieved for significantly more combinations than previously assumed. However, for these states the residual porosity was slightly different. This difference was explained by a parameter-dependent deformation factor of the droplets, which influences the maximal possible degree of filling during manufacturing. For the optimization of arbitrary parameter sets, an analytical model was derived.
Scaffold Using Chitosan, Agarose, Cellulose, Dextran and Protein for Tissue Engineering—A Review
Authors: Samrot Antony V. , Sathiyasree Mahendran , Rahim Sadiq Batcha Abdul , Renitta Robinson Emilin , Kasipandian Kasirajan , Krithika Shree Sivasuriyan , Rajalakshmi Deenadhayalan , Shobana Nagarajan , Dhiva Shanmugaboopathi , Abirami Sasi , Visvanathan Sridevi , Mohanty Basanta Kumar , Sabesan Gokul Shankar , Chinni Suresh V.
Published: March 2023

Biological macromolecules like polysaccharides/proteins/glycoproteins have been widely used in the field of tissue engineering due to their ability to mimic the extracellular matrix of tissue. In addition to this, these macromolecules are found to have higher biocompatibility and no/lesser toxicity when compared to synthetic polymers. In recent years, scaffolds made up of proteins, polysaccharides, or glycoproteins have been highly used due to their tensile strength, biodegradability, and flexibility. This review is about the fabrication methods and applications of scaffolds made using various biological macromolecules, including polysaccharides like chitosan, agarose, cellulose, and dextran and proteins like soy proteins, zein proteins, etc. Biopolymer-based nanocomposite production and its application and limitations are also discussed in this review. This review also emphasizes the importance of using natural polymers rather than synthetic ones for developing scaffolds, as natural polymers have unique properties, like high biocompatibility, biodegradability, accessibility, stability, absence of toxicity, and low cost.
A Broad View on Robot Self-Defense: Rapid Scoping Review and Cultural Comparison
Authors: Cooney Martin , Shiomi Masahiro , Duarte Eduardo Kochenborger , Vinel Alexey
Published: March 2023

With power comes responsibility: as robots become more advanced and prevalent, the role they will play in human society becomes increasingly important. Given that violence is an important problem, the question emerges if robots could defend people, even if doing so might cause harm to someone. The current study explores the broad context of how people perceive the acceptability of such robot self-defense (RSD) in terms of (1) theory, via a rapid scoping review, and (2) public opinion in two countries. As a result, we summarize and discuss: increasing usage of robots capable of wielding force by law enforcement and military, negativity toward robots, ethics and legal questions (including differences to the well-known trolley problem), control in the presence of potential failures, and practical capabilities that such robots might require. Furthermore, a survey was conducted, indicating that participants accepted the idea of RSD, with some cultural differences. We believe that, while substantial obstacles will need to be overcome to realize RSD, society stands to gain from exploring its possibilities over the longer term, toward supporting human well-being in difficult times.
Multiscale Observation Product (MOP) for Temporal Flood Inundation Mapping of the 2015 Dallas Texas Flood
Authors: Sava Elena , Cervone Guido , Kalyanapu Alfred
Published: March 2023

This paper presents a new data fusion multiscale observation product (MOP) for flood emergencies. The MOP was created by integrating multiple sources of contributed open-source data with traditional spaceborne remote sensing imagery in order to provide a sequence of high spatial and temporal resolution flood inundation maps. The study focuses on the 2015 Memorial Day floods that caused up to USD 61 million dollars of damage. The Hydraulic Engineering Center River Analysis System (HEC-RAS) model was used to simulate water surfaces for the northern part of the Trinity River in Dallas, using reservoir surcharge releases and topographic data provided by the U.S. Army Corps of Engineers. A measure of fit assessment is performed on the MOP flood maps with the HEC-RAS simulated flood inundation output to quantify spatial differences. Estimating possible flood inundation using individual datasets that vary spatially and temporally allow to gain an understanding of how much each observational dataset contributes to the overall water estimation. Results show that water surfaces estimated by MOP are comparable with the simulated output for the duration of the flood event. Additionally, contributed data, such as Civil Air Patrol, although they may be geographically sparse, become an important data source when fused with other observation data.
Exploring the Potential of vis-NIR Spectroscopy as a Covariate in Soil Organic Matter Mapping
Authors: Yang Meihua , Chen Songchao , Guo Xi , Shi Zhou , Zhao Xiaomin
Published: March 2023

Robust soil organic matter (SOM) mapping is required by farms, but their generation requires a large number of samples to be chemically analyzed, which is cost prohibitive. Recently, research has shown that visible and near-infrared (vis-NIR) reflectance spectroscopy is a fast and accurate technique for estimating SOM in a cost-effective manner. However, few studies have focused on using vis-NIR spectroscopy as a covariate to improve the accuracy of spatial modeling. In this study, our objective was to compare the mapping accuracy from a spatial model using kriging methods with and without the covariate of vis-NIR spectroscopy. We split the 261 samples into a calibration set (104) for building the spectral predictive model, a test set for generating the vis-NIR augmented set from the prediction of the fitted spectral predictive model (131), and a validation set (26) for evaluating map accuracy. We used two datasets (235 samples) for Kriging: a laboratory-based dataset (Ld, observations from calibration and test datasets) and a laboratory-based dataset with vis-NIR augmented predictions (Au.p, observations from calibration and predictions from test dataset), a laboratory-based dataset with vis-NIR spectra as the covariance (Ld.co) and augmented dataset with predictions using vis-NIR with vis-NIR spectra for the covariance (Au.p.co). The first one to seven accumulated principal components of vis-NIR spectra were used as the covariates when we used the measurement of Ld.co and Au.p.co. The map accuracy was evaluated by the validation set for the four datasets using Kriging. The results indicated that adding vis-NIR spectra as covariates had great potential in improving the map accuracy using kriging, and much higher accuracies were observed for Ld.p.co (RMSE of 5.51 g kg−1) and Au.p.co (RMSE of 5.66 g kg−1) than without using vis-NIR spectra as covariates for Ld (RMSE of 7.12 g kg−1) and Au.p (RMSE of 7.69 g kg−1). With a similar model performance to Ld.p.co, Au.p.co can reduce the cost of laboratory analysis for 60% of soil samples, demonstrating its advantage in cost-efficiency for spatial modeling of soil information. Therefore, we conclude that vis-NIR spectra can be used as a cost-effective technique to obtain augmented data to improve fine-resolution spatial mapping of soil information.
GNSS High-Precision Augmentation for Autonomous Vehicles: Requirements, Solution, and Technical Challenges
Authors: Chen Liang , Zheng Fu , Gong Xiaopeng , Jiang Xinyuan
Published: March 2023

Autonomous driving is becoming a pivotal technology that can realize intelligent transportation and revolutionize the future of mobility. Various types of sensors, including perception sensors and localization sensors, are essential for high-level autonomous and intelligent vehicles (AIV). In this paper, the characteristics of different sensors are compared, and the application characteristics and requirements of AIV are analyzed in depth. These analyses indicate that: GNSS, as the unique localization sensor that can obtain an absolute position, can not only provide all-weather position and time information for internal multi-sensor fusion but also act as a standard spatiotemporal reference for all autonomous systems; Furthermore, AIVs aim to provide safety for a mass user base ranging from tens to hundreds of millions; for this, AIVs require a global wide-area and instantaneous precise positioning service with location privacy protection. Based on a “geometry-bound” description of road grade and vehicle size, it has been found that GNSS requirements in autonomous vehicles include decimeter-level positioning with the assurance of high integrity. Combined with high-integrity GNSS implementation in the civil aviation field, GNSS different technology routes, and commercial solutions, a state space representation (SSR)-based GNSS high-precision augmentation positioning solution for AIV is summarized and introduced. The solution can achieve instantaneous, precise positioning with high integrity in a wide area by utilizing passive positioning mode with location privacy protection. In addition, the research progress on key technologies in the solution and existing challenges is investigated in detail by reviewing a series of publications.
Absolute Localization of Targets Using a Phase-Measuring Sidescan Sonar in Very Shallow Waters
Authors: Borrelli Mark , Legare Bryan , McCormack Bryan , dos Santos Pedro Paulo Guy Martins , Solazzo Daniel
Published: March 2023

The detection, classification, and localization of targets or features on the seafloor in acoustic data are critical to many disciplines. This is most important in cases where human safety is in jeopardy, such as hazards to navigation, mitigation of mine countermeasures, or unexploded ordnance. This study quantifies the absolute localization of targets, in the form of inert unexploded ordnance, in very shallow waters (2–3 m) on two intertidal bottom types in a meso-tidal environment (tide range = ~3.0 m). The two sites, a sandy intertidal flat and a mixed sand and gravel beach with abundant cobble-sized material, were seeded at low tide with targets (wax-filled 60-, 81-, 105- and 155-mm, projectile and mortar shells). An RTK-GPS was used to collect positional data for the targets and an unoccupied aerial system (UAS) survey was conducted on both sites. At the next high-tide, a vessel-based acoustic survey was performed, and at the subsequent low tide, the targets were re-surveyed with RTK-GPS. We focus here on the sidescan backscatter from a phase-measuring sidescan sonar (PMSS) and the sources of uncertainty for absolute localization. A total of 1426 calls of acoustic targets were made within the sidescan backscatter data, yielding an accuracy of 0.41 ± 0.26 m, with 98.9% of all calls <1 m from their absolute location. Distance from nadir was the most significant source of uncertainty, and targets between 3–7 m had the lowest uncertainty (0.32 ± 0.23 m) with increasing values toward and away from nadir. Bathymetry and bathymetry-mode backscatter were less useful for the detection and classification of targets compared to sidescan backscatter, but once detected, the accuracy of absolute localization were similar. This is likely due to target calls from these two datasets that were orders of magnitude less and that focused on the larger sized targets, thus more work is needed to better understand these differences. Lastly, the absolute localization of targets detected on sandy and cobble bottoms for all datasets were statistically similar. These acoustic instruments, their datasets, and methods presented herein can better document the absolute localization within acoustic data for many uses in very shallow waters.
Accuracy and Precision Improvement of Temperature Measurement Using Statistical Analysis/Central Limit Theorem
Authors: Belo Francisco Antônio , Soares Manoel Brasileiro , Lima Filho Abel Cavalcante , Lima Thyago Leite de Vasconcelos , Adissi Marceu Oliveira
Published: March 2023

This paper describes a method for increasing the accuracy and precision of temperature measurements of a liquid based on the central limit theorem. A thermometer immersed in a liquid exhibits a response with determined accuracy and precision. This measurement is integrated with an instrumentation and control system that imposes the behavioral conditions of the central limit theorem (CLT). The oversampling method exhibited an increasing measurement resolution. Through periodic sampling of large groups, an increase in the accuracy and formula of the increase in precision is developed. A measurement group sequencing algorithm and experimental system were developed to obtain the results of this system. Hundreds of thousands of experimental results are obtained and seem to demonstrate the proposed idea’s validity.
Sensitive Room-Temperature Graphene Photothermoelectric Terahertz Detector Based on Asymmetric Antenna Coupling Structure
Authors: Hong Liang , Wang Lanxia , Cai Miao , Yao Yifan , Guo Xuguang , Zhu Yiming
Published: March 2023

A highly sensitive room-temperature graphene photothermoelectric terahertz detector, with an efficient optical coupling structure of asymmetric logarithmic antenna, was fabricated by planar micro-nano processing technology and two-dimensional material transfer techniques. The designed logarithmic antenna acts as an optical coupling structure to effectively localize the incident terahertz waves at the source end, thus forming a temperature gradient in the device channel and inducing the thermoelectric terahertz response. At zero bias, the device has a high photoresponsivity of 1.54 A/W, a noise equivalent power of 19.8 pW/Hz1/2, and a response time of 900 ns at 105 GHz. Through qualitative analysis of the response mechanism of graphene PTE devices, we find that the electrode-induced doping of graphene channel near the metal-graphene contacts play a key role in the terahertz PTE response. This work provides an effective way to realize high sensitivity terahertz detectors at room temperature.
Heart Rate Variability Based Estimation of Maximal Oxygen Uptake in Athletes Using Supervised Regression Models
Authors: Balakarthikeyan Vaishali , Jais Rohan , Vijayarangan Sricharan , Sreelatha Premkumar Preejith , Sivaprakasam Mohanasankar
Published: March 2023

Wearable Heart Rate monitors are used in sports to provide physiological insights into athletes’ well-being and performance. Their unobtrusive nature and ability to provide reliable heart rate measurements facilitate the estimation of cardiorespiratory fitness of athletes, as quantified by maximum consumption of oxygen uptake. Previous studies have employed data-driven models which use heart rate information to estimate the cardiorespiratory fitness of athletes. This signifies the physiological relevance of heart rate and heart rate variability for the estimation of maximal oxygen uptake. In this work, the heart rate variability features that were extracted from both exercise and recovery segments were fed to three different Machine Learning models to estimate maximal oxygen uptake of 856 athletes performing Graded Exercise Testing. A total of 101 features from exercise and 30 features from recovery segments were given as input to three feature selection methods to avoid overfitting of the models and to obtain relevant features. This resulted in the increase of model’s accuracy by 5.7% for exercise and 4.3% for recovery. Further, post-modelling analysis was performed to remove the deviant points in two cases, initially in both training and testing and then only in training set, using k-Nearest Neighbour. In the former case, the removal of deviant points led to a reduction of 19.3% and 18.0% in overall estimation error for exercise and recovery, respectively. In the latter case, which mimicked the real-world scenario, the average R value of the models was observed to be 0.72 and 0.70 for exercise and recovery, respectively. From the above experimental approach, the utility of heart rate variability to estimate maximal oxygen uptake of large population of athletes was validated. Additionally, the proposed work contributes to the utility of cardiorespiratory fitness assessment of athletes through wearable heart rate monitors.
Discriminatively Unsupervised Learning Person Re-Identification via Considering Complicated Images
Authors: Quan Rong , Xu Biaoyi , Liang Dong
Published: March 2023

State-of-the-art purely unsupervised learning person re-ID methods first cluster all the images into multiple clusters and assign each clustered image a pseudo label based on the cluster result. Then, they construct a memory dictionary that stores all the clustered images, and subsequently train the feature extraction network based on this dictionary. All these methods directly discard the unclustered outliers in the clustering process and train the network only based on the clustered images. The unclustered outliers are complicated images containing different clothes and poses, with low resolution, severe occlusion, and so on, which are common in real-world applications. Therefore, models trained only on clustered images will be less robust and unable to handle complicated images. We construct a memory dictionary that considers complicated images consisting of both clustered and unclustered images, and design a corresponding contrastive loss by considering both kinds of images. The experimental results show that our memory dictionary that considers complicated images and contrastive loss can improve the person re-ID performance, which demonstrates the effectiveness of considering unclustered complicated images in unsupervised person re-ID.
Online Learning-Based Hybrid Tracking Method for Unmanned Aerial Vehicles
Authors: Son Sohee , Lee Injae , Cha Jihun , Choi Haechul
Published: March 2023

Tracking unmanned aerial vehicles (UAVs) in outdoor scenes poses significant challenges due to their dynamic motion, diverse sizes, and changes in appearance. This paper proposes an efficient hybrid tracking method for UAVs, comprising a detector, tracker, and integrator. The integrator combines detection and tracking, and updates the target’s features online while tracking, thereby addressing the aforementioned challenges. The online update mechanism ensures robust tracking by handling object deformation, diverse types of UAVs, and changes in background. We conducted experiments on custom and public UAV datasets to train the deep learning-based detector and evaluate the tracking methods, including the commonly used UAV123 and UAVL datasets, to demonstrate generalizability. The experimental results show the effectiveness and robustness of our proposed method under challenging conditions, such as out-of-view and low-resolution scenarios, and demonstrate its performance in UAV detection tasks.
LoRa, Zigbee and 5G Propagation and Transmission Performance in an Indoor Environment at 868 MHz
Authors: Robles-Enciso Ricardo , Morales-Aragón Isabel Pilar , Serna-Sabater Alfredo , Martínez-Inglés María Teresa , Mateo-Aroca Antonio , Molina-Garcia-Pardo Jose-María , Juan-Llácer Leandro
Published: March 2023

In this work, we present power and quality measurements of four transmissions using different emission technologies in an indoor environment, specifically a corridor, at the frequency of 868 MHz under two non-line-of-sight (NLOS) conditions. A narrowband (NB) continuous wave (CW) signal has been transmitted, and its received power has been measured with a spectrum analyzer, LoRa and Zigbee signals have also been transmitted, and their Received Signal Strength Indicator (RSSI) and bit error rate (BER) have been measured using the transceivers themselves; finally, a 20 MHz bandwidth 5G QPSK signal has also been transmitted and their quality parameters, such as SS-RSRP, SS-RSRQ and SS-RINR, have been measured using a SA. Thereafter, two fitting models, the Close-in (CI) model and the Floating-Intercept (FI) model, were used to analyze the path loss. The results show that slopes below 2 for the NLOS-1 zone and above 3 for the NLOS-2 zone have been found. Moreover, the CI and FI model behave very similarly in the NLOS-1 zone, while in the NLOS-2 zone, the CI model has poor accuracy in contrast to the FI model, which achieves the best accuracy in both NLOS situations. From these models, the power predicted with the FI model has been correlated with the measured BER value, and power margins have been established for which LoRa and Zigbee would each reach a BER greater than 5%; likewise, −18 dB has been established for the SS-RSRQ of 5G transmission.
Hate and Incivilities in Hashtags against Women Candidates in Chile (2021–2022)
Authors: Beltrán Jarnishs , Walker Paula , Jara René
Published: March 2023

This study is interested in the phenomenon of violence in social networks against women who hold political office in the framework of the Chilean constitutional process (2021–2022). To study this major socio-political phenomenon, we have used the tracking database “Women and Politics”, composed of 2,912,732 Twitter posts mentioning women candidates and collected between July 2021 and September 2022. Based on this data, we analyzed the network of hashtags by electoral list at points in time: all 2021 messages, all 2022 messages and only hate messages published in 2022 (n = 563,223), codified by an automated detection method. The results of the study reveal that hashtags extracted from messages containing hate speech are better understood under the concept of incivilities. These were expressed in a two-phase electoral process: the presidential election and the constitutional plebiscite. The implications and limits of this study are discussed and considered in context in the conclusion.
Evaluating the Impacts of a Research Ethics Training Course on University Researchers
Authors: Knight Jasper
Published: March 2023

Training in research ethics is an essential part of professional development for graduate students and academic and research staff at universities and other research institutions. Certificated training in research ethics has been offered at the University of the Witwatersrand, Johannesburg, South Africa, since 2019. This training comprises a 4 h content-based workshop followed by a written assignment with attendees who are mainly graduate students and academic staff of the University. This study presents the results of an anonymous online survey that evaluated the impacts of the ethics training on researcher professional activities, in particular where their research deals with human participants. Those invited to take part in the survey were the successful attendees who had attained a Certificate of Competence in Research Ethics. Results (n = 92) showed that the majority of respondents were satisfied with the nature, format and depth of content of the training, and reported that it has a positive impact on their development as researchers. Specifically, this included thinking through their project design, and developing critical thinking and problem solving skills related to their project. Overall, the results highlight the importance of research ethics training in researcher development, as well as engendering critical reflection on ethical issues in different research contexts. It also shows the importance of ethics training in a ‘live’ session where participants are able to ask questions, engage in debate, and undertake a written assessment that tests their application of ethics concepts.
The Dietary Carbon Footprint of Portuguese Adults: Defining and Assessing Mitigation Scenarios for Greenhouse Gas Emissions
Authors: Rocha Cristóvão Fraga Andrade Pereira da , Silva Catarina de Sousa Tavares Pinho da , Silva Rafaela Martins da , Oliveira Manuel Joaquim da Silva , Neto Belmira de Almeida Ferreira
Published: March 2023

The food chain is a large contributor to environmental pollution, especially greenhouse gas emissions, strongly associated with the consumption of animal-based proteins. The understanding of the negative environmental impacts of dietary habits by the population is of the utmost importance to provide the means to effect change to more sustainable eating patterns. The main purpose of this study was to assess the carbon footprint of animal protein consumption in Portugal, while also evaluating six mitigation scenarios aiming to lower greenhouse gas emissions through strategic changes to the animal protein consumption of current dietary habits. Overall, the carbon footprint associated with animal protein consumption is 2.63 kg CO2 eq/(cap⋅day) nationally and 28.4 t CO2 eq/month for the faculty canteen. Meat is by far the largest contributor to the carbon footprint in both cases, with beef being its “hotspot”. All scenarios showed significant reduction potentials, with values ranging from 16% (lower value for both the national case and the faculty canteen) to 71% (faculty canteen). In sum, substantial carbon footprint reductions can be attained if policymakers support the implementation of effective measures to promote a shift in the current animal protein consumption towards more sustainable eating habits.
Perceived CSR on Career Satisfaction: A Moderated Mediation Model of Cultural Orientation (Collectivism and Masculinity) and Organisational Pride
Authors: Mansour Mourad , Alaghbari Mohammed Abdulrazzaq , Beshr Baligh , Al-Ghazali Basheer M.
Published: March 2023

Previous studies depicted an association between perceived corporate social responsibility (CSR) and career satisfaction. Yet, the understanding of this fundamental connection is limited. This study examined the micro-foundations of CSR to elucidate the impact of workers’ CSR opinions on their career satisfaction. We established a moderated mediation model that incorporated perceived CSR, career satisfaction, organisational pride, and cultural alignment (collectivism and masculinity) based on a sample of 383 respondents using convenience sampling. Data were gathered on employees working in Saudi Arabian industries with well-executed CSR programs. Andrew Hayes’ Process Macros were used to test the hypotheses. Results showed that organisational pride partially mediated the association between perceived CSR and career satisfaction. Masculinity weakened the association between perceived CSR and organisational pride, and negatively moderated the association between perceived CSR, organisational pride, and career satisfaction. Conversely, collectivism positively moderated the perceived CSR and organisational pride link. This study extends the CSR literature by investigating one of the under-researched outcomes of CSR at an employee level, that is, career satisfaction. It also adds to the current body of knowledge by exploring the boundary conditions of the perception–emotion–behaviour link in employees. This study recommends that policymakers should focus more on CSR programs and collectivism to improve the career satisfaction of employees. Limitations and future recommendations are also discussed at the end.
Seasonal Differences in Ecophysiological Performance between Resprouters and Non-Resprouters across an Aridity Gradient in Northwest Tunisia
Authors: Nefzi Khaoula , Voltas Jordi , Kefi Bochra Bejaoui , Baraket Mokhtar , Rzigui Touhami , Martin Patrick , M’Hamdi Naceur , Msaada Kamel , Nasr Zouhair
Published: March 2023

Understanding the functioning of shrub species during dry periods is necessary to forecast ecosystem responses to future climates, particularly in Mediterranean environments. We evaluated the seasonal changes in leaf gas exchange, hydraulic traits, carbon and nitrogen isotopes, and non-structural carbohydrates of seeders and resprouting shrub species typical of Aleppo pine forests across an aridity gradient in Tunisia: Djebel Zaghouan (subhumid climate), Djebel Mansour (semiarid transitional climate), and Djebel El Sarj (semi-arid climate). We monitored seven woody species: Pistacia lentiscus, Erica multiflora, Phillyrea latifolia (resprouters), Cistus monspeliensis, Rosmarinus officinalis (seeders), Globularia alypum, and Calicotome villosa (resprouters-seeders). The seasonal variation in leaf water content was usually higher in seeders than in resprouters and was associated with higher resistance to embolism. In contrast, the seasonal variation in non-structural carbohydrates was higher in resprouters, especially at the driest site. Both δ13C and δ15N displayed seasonal enrichment-depletion patterns, with seeders showing an overall higher δ13C in summer than in spring, consistent with a water-saving strategy of increasing water use efficiency. Discriminant analysis suggested that resprouters can sustain a positive carbon balance during drought periods. The differential impact of summer droughts on water status and the ecophysiology of these plant strategies may lead to different ecosystem dynamics depending on whether climate change tips the balance towards a preponderance of stressors (drought) or disturbances (fire) in dry Mediterranean areas.
The Potential for Healthy, Sustainable, and Equitable Transport Systems in Africa and the Caribbean: A Mixed-Methods Systematic Review and Meta-Study
Authors: Brugulat-Panés Anna , Randall Lee , de Sá Thiago Hérick , Anil Megha , Kwan Haowen , Tatah Lambed , Woodcock James , Hambleton Ian R. , Mogo Ebele R. I. , Micklesfield Lisa , Pley Caitlin , Govia Ishtar , Matina Sostina Spiwe , Makokha Caroline , Dambisya Philip M. , Karim Safura Abdool , Pujol-Busquets Georgina , Okop Kufre , Mba Camille M. , Ware Lisa J. , Assah Felix , Nembulu Betty , Mukoma Gudani , Lucas Warren Covelé , Bennett Nadia , Tulloch-Reid Marshall K. , Awinja Alice Charity , Anand Tanmay , Foley Louise
Published: March 2023

The Human Mobility Transition model describes shifts in mobility dynamics and transport systems. The aspirational stage, ‘human urbanism’, is characterised by high active travel, universal public transport, low private vehicle use and equitable access to transport. We explored factors associated with travel behaviour in Africa and the Caribbean, investigating the potential to realise ‘human urbanism’ in this context. We conducted a mixed-methods systematic review of ten databases and grey literature for articles published between January 2008 and February 2019. We appraised study quality using Critical Appraisal Skills Programme checklists. We narratively synthesized qualitative and quantitative data, using meta-study principles to integrate the findings. We identified 39,404 studies through database searching, mining reviews, reference screening, and topic experts’ consultation. We included 129 studies (78 quantitative, 28 mixed-methods, 23 qualitative) and 33 grey literature documents. In marginalised groups, including the poor, people living rurally or peripheral to cities, women and girls, and the elderly, transport was poorly accessible, travel was characterised by high levels of walking and paratransit (informal public transport) use, and low private vehicle use. Poorly controlled urban growth (density) and sprawl (expansion), with associated informality, was a salient aspect of this context, resulting in long travel distances and the necessity of motorised transportation. There were existing population-level assets in relation to ‘human urbanism’ (high levels of active travel, good paratransit coverage, low private vehicle use) as well as core challenges (urban sprawl and informality, socioeconomic and gendered barriers to travel, poor transport accessibility). Ineffective mobility systems were a product of uncoordinated urban planning, unregulated land use and subsequent land use conflict. To realise ‘human urbanism’, integrated planning policies recognising the linkages between health, transport and equity are needed. A shift in priority from economic growth to a focus on broader population needs and the rights and wellbeing of ordinary people is required. Policymakers should focus attention on transport accessibility for the most vulnerable.
Identifying Chinese Tourists’ Shopping Values and Their Consequences in the Context of a Duty-Free Shop: The Moderating Role of Country Image
Authors: Hwang Jinsoo , Joo Kyuhyeon , Kim Insin
Published: March 2023

The objective of this study is to identify the role of Chinese tourists’ shopping values in the formation of their outcome variables. This study more specifically proposes that two dimensions of shopping values, which include utilitarian and hedonic shopping values, positively affect brand prestige. In addition, it was hypothesized that brand prestige helps in regard to enhancing well-being perceptions and brand preference. It was also proposed that well-being perceptions and brand preference have a positive influence on word-of-mouth. This study also hypothesized the moderating role of country image in the proposed model. The survey responses were collected from 634 Chinese duty-free tourists. The data analysis results showed that both utilitarian and hedonic shopping values significantly affect brand prestige. Moreover, brand prestige was found to be a significant determinant of well-being perceptions, and well-being perceptions positively affect brand preference. Brand preference is a critical factor affecting word-of-mouth. Lastly, country image played a moderating role in the relationship between brand prestige and well-being perceptions and brand preference and word-of-mouth.
Short-Term Effects of Air Pollution on Mortality in the Urban Area of Thessaloniki, Greece
Authors: Parliari Daphne , Giannaros Christos , Papadogiannaki Sofia , Melas Dimitrios
Published: March 2023

This study examines the effects of short-term exposure to PM10 and O3 on all-cause, cardiorespiratory, and cerebrovascular mortality in the urban area of Thessaloniki, Greece. An analysis was performed on the vulnerable subgroup (the elderly population). The primary effect estimates employed were the relative risks for every 10 µg/m3 increase in air pollutant concentrations. Strong associations between PM10 and O3 levels on mortality were reported, with the elderly people becoming frailer. An increase of 10 μgr/m3 in PM10 concentration resulted in a 2.3% (95% CI: 0.8–3.8) and 2% (95% CI: 0.1–4.5) increase in total and cardiorespiratory mortality, respectively. O3 concentrations showed even stronger associations for all-cause (3.9%, 95% CI: 2.5–5.3) and cardiorespiratory deaths (5.3%, 95% CI: 3.1–7.7) with 10 μgr/m3 increases; no statistically significant associations were found for cerebrovascular causes, while both pollutants presented stronger impacts on health between day 0 and 3. Concerning the elderly, the total mortality rose by 3.2% (95% CI: 1.5–5) due to PM10 concentrations and by 4.4% (95% CI: 2.9–6) due to O3 concentrations. In total, 242 (170) all-cause deaths were annually attributed to the PM10 (O3) level in Thessaloniki. In the efforts towards achieving a sustainable environment for humanity, health benefits resulting from two air pollution abatement scenarios (a 20% reduction in PM10 levels and full compliance to the European Union PM10 limits) were quantified. The analysis led to a respective decrease in total excess mortality by 0.4% and 1.8%, respectively. This outcome stresses the necessity of appropriate civil protection actions and provides valuable scientific knowledge to national and regional administrations in order to develop proper health and air quality plans.
Slope Stability and Effectiveness of Treatment Measures during Earthquake
Authors: Zhou Linlu , Su Lei , Wang Zhuang , Zhu Dongchun , Shi Wei , Ling Xianzhang
Published: March 2023

Slopes are prone to instability during earthquakes, which will cause geological disasters such as landslides and pose a great threat to people’s lives and property. Therefore, it is necessary to analyze the stability of slopes and the effectiveness of treatment measures during earthquakes. In this study, an actual slope in the creeping slide stage was selected and located in an area where earthquakes occur frequently. Once the slope experiences instability, it will produce great damage. Therefore, a finite difference program, Fast Lagrangian Analysis of Continua in Two Dimensions (FLAC2D), was employed in the numerical simulation to explore the stability of the slope before and after treatment under earthquake action. Different from previous studies, this study explores the effectiveness of various treatment measures on slope stability during earthquake. The computed results show that the stability of the slope is greatly influenced by earthquakes, and the slope displacement under seismic conditions is far larger than that under natural conditions. Three treatment measures, including excavation, anti-slide piles, and anchor cables, can significantly reduce slope displacement and the internal force on anti-slide piles, and improve the stability of a slope during an earthquake. This will provide a valuable reference for the strengthening strategies of unstable slopes. The analysis technique as well as the derived insights are of significance for slope stability and the effectiveness of treatment measures.