bluuebunny/crossref_metadata_2025 huggingface dataset:
Eco-Friendly Incorporation of Crumb Rubber and Waste Bagasse Ash in Bituminous Concrete Mix
Authors: Ullah Sheraz , Shah Muhammad , Alqurashi Muwaffaq , Javed Muhammad , Dawood Osama , Aslam Fahid , Tariq Muhammad , Hussain Enas
Published: March 2022

The consumption of waste materials in the construction sector is a sustainable approach that helps in reducing the environmental pollution and decreases the construction cost. The present research work emphasizes the mechanical properties of bituminous concrete mix prepared with crumb rubber (CR) and waste sugarcane bagasse ash (SCBA). For the preparation of bituminous concrete mix specimens with CR and SCBA, the effective bitumen content was determined using the Marshall Mix design method. A total of 15 bituminous concrete mix specimens with 4%, 4.5%, 5%, 5.5% and 6% of bitumen content were prepared, and the effective bitumen content turned out to be 4.7%. The effect of five different CR samples of 2%, 4%, 6%, 8% and 10% by weight of total mix and SCBA samples of 25%, 50%, 75% and 100% by weight of filler were investigated on the performance of bituminous concrete. A total of 180 samples with different percentages of CR and SCBA were tested for indirect tensile strength (ITS) and Marshall Stability, and the results were compared with conventional bituminous concrete mix. It was observed that the stability values rose with an increase in CR percentage up to 6%, while the flow values rose as the percentage of SCBA increased in the mix. Maximum ITS results were observed at 4% CR and 25% SCBA replacement levels. However, a decrease in stability and ITS result was observed as the percentages of CR and SCBA increased beyond 4% and 25%, respectively. We concluded that the optimum CR and SCBA content of 4% and 25%, respectively, can be effectively used as a sustainable alternative in bituminous concrete mix.
Residual Stress Induced by Addition of Nanosized TiC in Titanium Matrix Composite
Authors: Myalska-Głowacka Hanna , Chmiela Bartosz , Godzierz Marcin , Sozańska Maria
Published: March 2022

A hot pressing process was employed to produce titanium-based composites. Nanosized TiC particles were incorporated in order to improve mechanical properties of the base material. The amount of nanosized additions in the composites was 0.5, 1.0, and 2.0 wt %, respectively. Moreover, a TiB phase was produced by in situ method during sintering process. The microstructure of the Ti–TiB–TiC composites was characterized by scanning electron microscopy (SEM), electron probe microanalysis (EPMA), electron backscatter diffraction (EBSD), and X-ray diffraction (XRD) techniques. Due to the hot pressing process the morphology of primary TiC particles was changed. Observed changes in the size and shape of the reinforcing phase suggest the transformation of primary carbides into secondary carbides. Moreover, an in situ formation of TiB phase was observed in the material. Additionally, residual stress measurements were performed and revealed a mostly compressive nature with the fine contribution of shear. With an increase in TiC content, linear stress decreased, which was also related with the presence of the TiB phase.
Salmon Protein Hydrolysate Potentiates the Growth Inhibitory Effect of Bicalutamide on Human Prostate Cancer Cell Lines LNCaP and PC3 by Modulating Iron Homeostasis
Authors: Bjerknes Christian , Framroze Bomi , Currie Crawford , Pettersen Caroline Hild Hakvåg , Axcrona Karol , Hermansen Erland
Published: March 2022

Prostate cancer is a common cause of cancer death in men. In advanced stages of prostate cancer, androgen deprivation therapy (ADT) is initiated. Despite ADT, prostate cancers invariably progress to become androgen independent. A growing body of evidence implicates iron dysmetabolism in prostate cancer progression. A bioactive peptide-rich salmon protein hydrolysate (SPH) has previously been demonstrated to modulate iron homeostatic mechanisms. In the present study, the anticancer effect of SPH and bicalutamide co-treatment on LNCaP and PC3 prostate cancer cell proliferation was investigated. Our results found that SPH potentiates the anti-proliferative effect of bicalutamide in a dose-dependent manner for both cell lines. In the presence of 160 µg/mL SPH, co-treatment with 1.0 µM bicalutamide decreased LNCaP cells’ relative colony survival from 25% (1.0 µM bicalutamide monotreatment) to 2% after culturing for 12 days. For PC3 cells, the relative colony survival diminished from 52% (10.0 µM bicalutamide) to 32% at an SPH concentration of 160 µg/mL. Gene expression profiling, employing quantitative real-time PCR, revealed that the inhibitory effects were related to significant FTH1 up-regulation with a concomitant TFRC down-regulation. In conclusion, our results provide in vitro evidence that SPH potentiates the growth inhibitory effect of bicalutamide on prostate cancer cells by modulating iron homeostasis mechanisms.
Culturable Diversity of Thraustochytrids from Coastal Waters of Qingdao and Their Fatty Acids
Authors: Bai Mohan , Sen Biswarup , Wen Shuai , Ye Huike , He Yaodong , Zhang Xiaobo , Wang Guangyi
Published: March 2022

Thraustochytrids have gained significant attention in recent years because of their considerable ecological and biotechnological importance. Yet, the influence of seasons and habitats on their culturable diversity and lipid profile remains poorly described. In this study, a total of 58 thraustochytrid strains were isolated from the coastal waters of Qingdao, China. These strains were phylogenetically close to five thraustochytrid genera, namely Botryochytrium, Oblongichytrium, Schizochytrium, Thraustochytrium, and Sicyoidochytrium. Most of the isolated strains were classified into the genera Thraustochytrium and Oblongichytrium. Further diversity analysis revealed that samples collected from nutrient-rich habitats and during summer/fall yielded significantly higher culturable diversity of thraustochytrids than those from low-nutrient habitats and winter/spring. Moreover, sampling habitats and seasons significantly impacted the fatty acid profiles of the strains. Particularly, the Oblongichytrium sp. OC931 strain produced a significant amount (153.99 mg/L) of eicosapentaenoic acid (EPA), accounting for 9.12% of the total fatty acids, which was significantly higher than that of the previously reported Aurantiochytrium strains. Overall, the results of this study fill the gap in our current understanding of the culturable diversity of thraustochytrids in the coastal waters and the impact of the sampling habitats and seasons on their capacity for lipid accumulation.
Fish Collagen Peptides Protect against Cisplatin-Induced Cytotoxicity and Oxidative Injury by Inhibiting MAPK Signaling Pathways in Mouse Thymic Epithelial Cells
Authors: Song Won Hoon , Kim Hye-Yoon , Lim Ye Seon , Hwang Seon Yeong , Lee Changyong , Lee Do Young , Moon Yuseok , Song Yong Jung , Yoon Sik
Published: March 2022

Thymic epithelial cells (TECs) account for the most abundant and dominant stromal component of the thymus, where T cells mature. Oxidative- or cytotoxic-stress associated injury in TECs, a significant and common problem in many clinical settings, may cause a compromised thymopoietic capacity of TECs, resulting in clinically significant immune deficiency disorders or impairment in the adaptive immune response in the body. The present study demonstrated that fish collagen peptides (FCP) increase cell viability, reduce intracellular levels of reactive oxygen species (ROS), and impede apoptosis by repressing the expression of Bax and Bad and the release of cytochrome c, and by upregulating the expression of Bcl-2 and Bcl-xL in cisplatin-treated TECs. These inhibitory effects of FCP on TEC damage occur via the suppression of ROS generation and MAPK (p38 MAPK, JNK, and ERK) activity. Taken together, our data suggest that FCP can be used as a promising protective agent against cytotoxic insults- or ROS-mediated TEC injury. Furthermore, our findings provide new insights into a therapeutic approach for the future application of FCP in the prevention and treatment of various types of oxidative- or cytotoxic stress-related cell injury in TECs as well as age-related or acute thymus involution.
What Was Old Is New Again: The Pennate Diatom Haslea ostrearia (Gaillon) Simonsen in the Multi-Omic Age
Authors: Gabed Noujoud , Verret Frédéric , Peticca Aurélie , Kryvoruchko Igor , Gastineau Romain , Bosson Orlane , Séveno Julie , Davidovich Olga , Davidovich Nikolai , Witkowski Andrzej , Kristoffersen Jon Bent , Benali Amel , Ioannou Efstathia , Koutsaviti Aikaterini , Roussis Vassilios , Gâteau Hélène , Phimmaha Suliya , Leignel Vincent , Badawi Myriam , Khiar Feriel , Francezon Nellie , Fodil Mostefa , Pasetto Pamela , Mouget Jean-Luc
Published: March 2022

The marine pennate diatom Haslea ostrearia has long been known for its characteristic blue pigment marennine, which is responsible for the greening of invertebrate gills, a natural phenomenon of great importance for the oyster industry. For two centuries, this taxon was considered unique; however, the recent description of a new blue Haslea species revealed unsuspected biodiversity. Marennine-like pigments are natural blue dyes that display various biological activities—e.g., antibacterial, antioxidant and antiproliferative—with a great potential for applications in the food, feed, cosmetic and health industries. Regarding fundamental prospects, researchers use model organisms as standards to study cellular and physiological processes in other organisms, and there is a growing and crucial need for more, new and unconventional model organisms to better correspond to the diversity of the tree of life. The present work, thus, advocates for establishing H. ostrearia as a new model organism by presenting its pros and cons—i.e., the interesting aspects of this peculiar diatom (representative of benthic-epiphytic phytoplankton, with original behavior and chemodiversity, controlled sexual reproduction, fundamental and applied-oriented importance, reference genome, and transcriptome will soon be available); it will also present the difficulties encountered before this becomes a reality as it is for other diatom models (the genetics of the species in its infancy, the transformation feasibility to be explored, the routine methods needed to cryopreserve strains of interest).
Preheating Behaviors of Iron Ore Pellets with Humic Substance-Based Binder
Authors: Meng Feiyu , Ou Yang , Li Ke , Yang Yongbin , Zhong Qiang , Li Qian , Jiang Tao
Published: March 2022

Humic substance-based binder (HB) has been found to be an effective substitution for bentonite in the production of iron ore pellets. In this study, it was found that the preheating time needed to be prolonged during the pelletization processing which is a remarkable feature of pellets with HB instead of bentonite. As far as the oxidation behaviors were concerned, a manifest oxidation hysteresis platform was observed in the FeO content vs. preheating time curve during the second minute in the preheating process, which implied that the emission of humic substance noticeably interfered with oxidation process pellets. Consequently, in contrast to bentonite, the magnetite phase could not be completely transformed into hematite until the preheating time reached 16 min. Meanwhile, the SEM-EDS analysis showed that the crystal grains of preheated pellets with HB were well interconnected when the preheating time was 16 min. This also verified that the optimal preheating time of pellets with HB (16 min) was longer than that of pellets with bentonite (10 min).
Phase Transformation in TiNi Nano-Wafers for Nanomechanical Devices with Shape Memory Effect
Authors: Kartsev Alexey , Lega Peter V. , Orlov Andrey P. , Pavlov Alexander I. , von Gratowski Svetlana , Koledov Victor V. , Ilin Alexei S.
Published: March 2022

Recently, Ti-Ni based intermetallic alloys with shape memory effect (SME) have attracted much attention as promising functional materials for the development of record small nanomechanical tools, such as nanotweezers, for 3D manipulation of the real nano-objects. The problem of the fundamental restrictions on the minimal size of the nanomechanical device with SME for manipulation is connected with size effects which are observed in small samples of Ti-Ni based intermetallic alloys with thermoplastic structural phase transition from austenitic high symmetrical phase to low symmetrical martensitic phase. In the present work, by combining density functional theory and molecular dynamics modelling, austenite has been shown to be more stable than martensite in nanometer-sized TiNi wafers. In this case, the temperature of the martensitic transition asymptotically decreases with a decrease in the plate thickness h, and the complete suppression of the phase transition occurs for a plate with a thickness of 2 nm, which is in qualitative agreement with the experimental data. Moreover, the theoretical values obtained indicate the potential for even greater minimization of nanomechanical devices based on SME in TiNi.
Electric Properties of Multiwalled Carbon Nanotubes Dispersed in Liquid Crystals and Their Influence on Freedericksz Transitions
Authors: Petrescu Emil , Cirtoaje Cristina
Published: March 2022

Liquid crystal composites with multiwalled carbon nanotubes present dielectric properties considerably different from those of pure liquid crystal (LC). Using a proper dispersion of nanotubes in the LC-sample and a theoretical model in agreement with the experimental configuration, the dielectric permittivities of multiwalled carbon nanotubes are calculated. The influence of dielectric properties on the Freedericksz transition threshold is discussed. Theoretical values for dielectric permittivities of multiwalled carbon nanotubes are calculated for different temperatures
A Bilayer Skin-Inspired Hydrogel with Strong Bonding Interface
Authors: He Chubin , Xu Xiuru , Lin Yang , Cui Yang , Peng Zhengchun
Published: March 2022

Conductive hydrogels are widely used in sports monitoring, healthcare, energy storage, and other fields, due to their excellent physical and chemical properties. However, synthesizing a hydrogel with synergistically good mechanical and electrical properties is still challenging. Current fabrication strategies are mainly focused on the polymerization of hydrogels with a single component, with less emphasis on combining and matching different conductive hydrogels. Inspired by the gradient modulus structures of the human skin, we propose a bilayer structure of conductive hydrogels, composed of a spray-coated poly(3,4-dihydrothieno-1,4-dioxin): poly(styrene sulfonate) (PEDOT:PSS) as the bonding interface, a relatively low modulus hydrogel on the top, and a relatively high modulus hydrogel on the bottom. The spray-coated PEDOT:PSS constructs an interlocking interface between the top and bottom hydrogels. Compared to the single layer counterparts, both the mechanical and electrical properties were significantly improved. The as-prepared hydrogel showed outstanding stretchability (1763.85 ± 161.66%), quite high toughness (9.27 ± 0.49 MJ/m3), good tensile strength (0.92 ± 0.08 MPa), and decent elastic modulus (69.16 ± 8.02 kPa). A stretchable strain sensor based on the proposed hydrogel shows good conductivity (1.76 S/m), high sensitivity (a maximum gauge factor of 18.14), and a wide response range (0–1869%). Benefitting from the modulus matching between the two layers of the hydrogels, the interfacial interlocking network, and the patch effect of the PEDOT:PSS, the strain sensor exhibits excellent interface robustness with stable performance (>12,500 cycles). These results indicate that the proposed bilayer conductive hydrogel is a promising material for stretchable electronics, soft robots, and next-generation wearables.
Treatment of Chrysanthemum Synthetic Seeds by Air SDBD Plasma
Authors: Škoro Nikola , Živković Suzana , Jevremović Slađana , Puač Nevena
Published: March 2022

Herein, we present the effect of surface dielectric barrier discharge (SDBD) air cold plasma on regrowth of chrysanthemum synthetic seeds (synseeds) and subsequent plantlet development. The plasma system used in this study operates in air at the frequency of 50 Hz. The detailed electrical characterization of SDBD was shown, as well as air plasma emission spectra obtained by optical emission spectroscopy. The chrysanthemum synseeds (encapsulated shoot tips) were treated in air plasma for different treatment times (0, 5 or 10 min). Plasma treatment significantly improved the regrowth and whole plantlet development of chrysanthemum synseeds under aseptic (in vitro) and non-aseptic (ex vitro) conditions. We evaluated the effect of SDBD plasma on synseed germination of four chrysanthemum cultivars after direct sowing in soil. Germination of synseeds directly sowed in soil was cultivar-dependent and 1.6−3.7 fold higher after plasma treatment in comparison with untreated synseeds. The study showed a highly effective novel strategy for direct conversion of simple monolayer alginate chrysanthemum synseeds into entire plantlets by plasma pre-conversion treatment. This treatment reduced contamination and displayed a considerable ex vitro ability to convert clonally identical chrysanthemum plants.
Design of Experiments-Based Optimization of Flavonoids Extraction from Daphne genkwa Flower Buds and Flavonoids Contents at Different Blooming Stages
Authors: Kim Min-Kyoung , Park Geonha , Ji Yura , Lee Yun-Gyo , Choi Minsik , Go Seung-Hyeon , Son Miwon , Jang Young-Pyo
Published: March 2022

The flower buds of Daphne genkwa have been reported as a potent resource associated with anti-angiogenic, anti-tumor, anti-rheumatoid arthritis activities, as well as immunoregulation. This paper aimed to establish an optimal extraction method for flavonoids, as active phytochemicals, and to conduct a comparative analysis by profiling the different blooming stages. Optimized shaking extraction conditions from the design of experiments (DoE), such as minutely mixture design, 23 full factorial design, and polynomial regression analysis, involved an agitation speed of 150 rpm and temperature of 65 °C for 12 h in 56% (v/v) acetone solvent. After, a comparative analysis was performed on three blooming stages, juvenile bud, mature purple bud, and complete flowering, by ultra-high-performance liquid chromatography-photodiode array-mass spectrometry (UHPLC-PDA-MS). Most flavonoids increased during bud growth and then decreased when the bud opened for blooming. In particular, apigenin 7-O-glucuronide, genkwanin 5-O-primeveroside, and genkwanin strikingly showcased this pattern. Furthermore, the raw spectrometric dataset was subjected to orthogonal projection to latent structures discriminant analysis (OPLS-DA) to find significant differences in the flavonoids from the juvenile bud, mature purple bud, and complete flowering. In conclusion, the present study facilitates an understanding of flavonoid change at different blooming stages and provides a momentous reference in the research of D. genkwa.
LASSO Homotopy-Based Sparse Representation Classification for fNIRS-BCI
Authors: Gulraiz Asma , Naseer Noman , Nazeer Hammad , Khan Muhammad Jawad , Khan Rayyan Azam , Shahbaz Khan Umar
Published: March 2022

Brain-computer interface (BCI) systems based on functional near-infrared spectroscopy (fNIRS) have been used as a way of facilitating communication between the brain and peripheral devices. The BCI provides an option to improve the walking pattern of people with poor walking dysfunction, by applying a rehabilitation process. A state-of-the-art step-wise BCI system includes data acquisition, pre-processing, channel selection, feature extraction, and classification. In fNIRS-based BCI (fNIRS-BCI), channel selection plays a vital role in enhancing the classification accuracy of the BCI problem. In this study, the concentration of blood oxygenation (HbO) in a resting state and in a walking state was used to decode the walking activity and the resting state of the subject, using channel selection by Least Absolute Shrinkage and Selection Operator (LASSO) homotopy-based sparse representation classification. The fNIRS signals of nine subjects were collected from the left hemisphere of the primary motor cortex. The subjects performed the task of walking on a treadmill for 10 s, followed by a 20 s rest. Appropriate filters were applied to the collected signals to remove motion artifacts and physiological noises. LASSO homotopy-based sparse representation was used to select the most significant channels, and then classification was performed to identify walking and resting states. For comparison, the statistical spatial features of mean, peak, variance, and skewness, and their combination, were used for classification. The classification results after channel selection were then compared with the classification based on the extracted features. The classifiers used for both methods were linear discrimination analysis (LDA), support vector machine (SVM), and logistic regression (LR). The study found that LASSO homotopy-based sparse representation classification successfully discriminated between the walking and resting states, with a better average classification accuracy (p < 0.016) of 91.32%. This research provides a step forward in improving the classification accuracy of fNIRS-BCI systems. The proposed methodology may also be used for rehabilitation purposes, such as controlling wheelchairs and prostheses, as well as an active rehabilitation training technique for patients with motor dysfunction.
Deep Learning-Based Monocular 3D Object Detection with Refinement of Depth Information
Authors: Hu Henan , Zhu Ming , Li Muyu , Chan Kwok-Leung
Published: March 2022

Recently, the research on monocular 3D target detection based on pseudo-LiDAR data has made some progress. In contrast to LiDAR-based algorithms, the robustness of pseudo-LiDAR methods is still inferior. After conducting in-depth experiments, we realized that the main limitations are due to the inaccuracy of the target position and the uncertainty in the depth distribution of the foreground target. These two problems arise from the inaccurate depth estimation. To deal with the aforementioned problems, we propose two innovative solutions. The first is a novel method based on joint image segmentation and geometric constraints, used to predict the target depth and provide the depth prediction confidence measure. The predicted target depth is fused with the overall depth of the scene and results in the optimal target position. For the second, we utilize the target scale, normalized with the Gaussian function, as a priori information. The uncertainty of depth distribution, which can be visualized as long-tail noise, is reduced. With the refined depth information, we convert the optimized depth map into the point cloud representation, called a pseudo-LiDAR point cloud. Finally, we input the pseudo-LiDAR point cloud to the LiDAR-based algorithm to detect the 3D target. We conducted extensive experiments on the challenging KITTI dataset. The results demonstrate that our proposed framework outperforms various state-of-the-art methods by more than 12.37% and 5.34% on the easy and hard settings of the KITTI validation subset, respectively. On the KITTI test set, our framework also outperformed state-of-the-art methods by 5.1% and 1.76% on the easy and hard settings, respectively.
Use of Robotic Devices for Gait Training in Patients Diagnosed with Multiple Sclerosis: Current State of the Art
Authors: Pérez-de la Cruz Sagrario
Published: March 2022

Multiple sclerosis (MS) is a neurodegenerative disease that produces alterations in balance and gait in most patients. Robot-assisted gait training devices have been proposed as a complementary approach to conventional rehabilitation treatment as a means of improving these alterations. The aim of this study was to investigate the available scientific evidence on the benefits of the use of robotics in the physiotherapy treatment in people with MS. A systematic review of randomized controlled trials was performed. Studies from the last five years on walking in adults with MS were included. The PEDro scale was used to assess the methodological quality of the included studies, and the Jadad scale was used to assess the level of evidence and the degree of recommendation. Seventeen studies met the eligibility criteria. For the improvement of gait speed, robotic devices do not appear to be superior, compared to the rest of the interventions evaluated. The methodological quality of the studies was moderate–low. For this reason, robot-assisted gait training is considered just as effective as conventional rehabilitation training for improving gait in people with MS.
A Novel Detection Scheme in Image Domain for Multichannel Circular SAR Ground-Moving-Target Indication
Authors: Dong Qinghai , Wang Bingnan , Xiang Maosheng , Wang Zhongbin , Wang Yachao , Song Chong
Published: March 2022

Circular synthetic aperture radar (CSAR), which can observe the region of interest for a long time and from multiple angles, offers the opportunity for moving-target detection (MTD). However, traditional MTD methods cannot effectively solve the problem of high probability of false alarm (PFA) caused by strong clutter. To mitigate this, a novel, three-step scheme combining clutter background extraction, multichannel clutter suppression, and the degree of linear consistency of radial velocity interferometric phase (DLRVP) test is proposed. In the first step, the spatial similarity of the scatterers and the correlation between sub-aperture images are fused to extract the strong clutter mask prior to clutter suppression. In the second step, using the data remaining after elimination of the background clutter in Step 1, an amplitude-based detector with higher processing gain is utilized to detect potential moving targets. In the third step, a novel test model based on DLRVP is proposed to further reduce the PFA caused by isolated strong scatterers. After the above processing, almost all false alarms are excluded. Measured data verified that the PFA of the proposed method is only 20% that of the comparison method, with improved detection of slow and weakly moving targets and with better robustness.
MFDroid: A Stacking Ensemble Learning Framework for Android Malware Detection
Authors: Wang Xusheng , Zhang Linlin , Zhao Kai , Ding Xuhui , Yu Mingming
Published: March 2022

As Android is a popular a mobile operating system, Android malware is on the rise, which poses a great threat to user privacy and security. Considering the poor detection effects of the single feature selection algorithm and the low detection efficiency of traditional machine learning methods, we propose an Android malware detection framework based on stacking ensemble learning—MFDroid—to identify Android malware. In this paper, we used seven feature selection algorithms to select permissions, API calls, and opcodes, and then merged the results of each feature selection algorithm to obtain a new feature set. Subsequently, we used this to train the base learner, and set the logical regression as a meta-classifier, to learn the implicit information from the output of base learners and obtain the classification results. After the evaluation, the F1-score of MFDroid reached 96.0%. Finally, we analyzed each type of feature to identify the differences between malicious and benign applications. At the end of this paper, we present some general conclusions. In recent years, malicious applications and benign applications have been similar in terms of permission requests. In other words, the model of training, only with permission, can no longer effectively or efficiently distinguish malicious applications from benign applications.
Applications and Innovations on Sensor-Enabled Wearable Devices
Authors: Torres-Sospedra Joaquín , Lohan Elena Simona , Molinaro Antonella , Moreira Adriano , Rusu-Casandra Alexandru , Smékal Zdenek
Published: March 2022

Multiple sensors are embedded in wearable devices [...]
An Efficient and Effective Deep Learning-Based Model for Real-Time Face Mask Detection
Authors: Habib Shabana , Alsanea Majed , Aloraini Mohammed , Al-Rawashdeh Hazim Saleh , Islam Muhammad , Khan Sheroz
Published: March 2022

Since December 2019, the COVID-19 pandemic has led to a dramatic loss of human lives and caused severe economic crises worldwide. COVID-19 virus transmission generally occurs through a small respiratory droplet ejected from the mouth or nose of an infected person to another person. To reduce and prevent the spread of COVID-19 transmission, the World Health Organization (WHO) advises the public to wear face masks as one of the most practical and effective prevention methods. Early face mask detection is very important to prevent the spread of COVID-19. For this purpose, we investigate several deep learning-based architectures such as VGG16, VGG19, InceptionV3, ResNet-101, ResNet-50, EfficientNet, MobileNetV1, and MobileNetV2. After these experiments, we propose an efficient and effective model for face mask detection with the potential to be deployable over edge devices. Our proposed model is based on MobileNetV2 architecture that extracts salient features from the input data that are then passed to an autoencoder to form more abstract representations prior to the classification layer. The proposed model also adopts extensive data augmentation techniques (e.g., rotation, flip, Gaussian blur, sharping, emboss, skew, and shear) to increase the number of samples for effective training. The performance of our proposed model is evaluated on three publicly available datasets and achieved the highest performance as compared to other state-of-the-art models.
Performance Evaluation of a Smart Bed Technology against Polysomnography
Authors: Siyahjani Farzad , Garcia Molina Gary , Barr Shawn , Mushtaq Faisal
Published: March 2022

The Sleep Number smart bed uses embedded ballistocardiography, together with network connectivity, signal processing, and machine learning, to detect heart rate (HR), breathing rate (BR), and sleep vs. wake states. This study evaluated the performance of the smart bed relative to polysomnography (PSG) in estimating epoch-by-epoch HR, BR, sleep vs. wake, mean overnight HR and BR, and summary sleep variables. Forty-five participants (aged 22–64 years; 55% women) slept one night on the smart bed with standard PSG. Smart bed data were compared to PSG by Bland–Altman analysis and Pearson correlation for epoch-by-epoch HR and epoch-by-epoch BR. Agreement in sleep vs. wake classification was quantified using Cohen’s kappa, ROC analysis, sensitivity, specificity, accuracy, and precision. Epoch-by-epoch HR and BR were highly correlated with PSG (HR: r = 0.81, |bias| = 0.23 beats/min; BR: r = 0.71, |bias| = 0.08 breaths/min), as were estimations of mean overnight HR and BR (HR: r = 0.94, |bias| = 0.15 beats/min; BR: r = 0.96, |bias| = 0.09 breaths/min). Calculated agreement for sleep vs. wake detection included kappa (prevalence and bias-adjusted) = 0.74 ± 0.11, AUC = 0.86, sensitivity = 0.94 ± 0.05, specificity = 0.48 ± 0.18, accuracy = 0.86 ± 0.11, and precision = 0.90 ± 0.06. For all-night summary variables, agreement was moderate to strong. Overall, the findings suggest that the Sleep Number smart bed may provide reliable metrics to unobtrusively characterize human sleep under real life-conditions.
A Composite Flexible Sensor for Direct Ventricular Assist Device
Authors: Yun Zhong , Li Kuibing , Jiang Hao , Tang Xiaoyan
Published: March 2022

A direct ventricular assist device is one of the effective means to treat patients with heart failure; the key point of the problem is the flexible sensor that can measure the drive pressure and shape variable of the heart auxiliary device. This study was based on the high-voltage electric field guidance process and the porous foaming process, and designed an implantable resistance/capacitive composite flexible sensor that can effectively detect the pressure and deformation signal caused by fine surface contact and pneumatic muscle expansion. Experiments showed the performance of composite sensors with special structure design was greatly improved compared with the control group—the strain measurement sensitivity was 22, pressure measurement sensitivity was up to 0.19 Kpa−1. Stable strain measurements were made up to 35 times and pressure measurements over 100 times. In addition, we solved the interference problem of resistance/capacitance flexible sensors through an optimized common substrate process. Finally, we tested a pneumatic muscle direct ventricular assist device with a composite flexible sensor on a model heart; the experiment showed that this resistance/capacitive composite flexible sensor can effectively detect surface contact with pneumatic muscle and the displacement signals.
Towards the Detection of GPS Spoofing Attacks against Drones by Analyzing Camera’s Video Stream
Authors: Davidovich Barak , Nassi Ben , Elovici Yuval
Published: March 2022

A Global Positioning System (GPS) spoofing attack can be launched against any commercial GPS sensor in order to interfere with its navigation capabilities. These sensors are installed in a variety of devices and vehicles (e.g., cars, planes, cell phones, ships, UAVs, and more). In this study, we focus on micro UAVs (drones) for several reasons: (1) they are small and inexpensive, (2) they rely on a built-in camera, (3) they use GPS sensors, and (4) it is difficult to add external components to micro UAVs. We propose an innovative method, based on the video stream captured by a drone’s camera, for the real-time detection of GPS spoofing attacks targeting drones. The proposed method collects frames from the video stream and their location (GPS coordinates); by calculating the correlation between each frame, our method can detect GPS spoofing attacks on drones. We first analyze the performance of the suggested method in a controlled environment by conducting experiments on a flight simulator that we developed. Then, we analyze its performance in the real world using a DJI drone. Our method can provide different levels of security against GPS spoofing attacks, depending on the detection interval required; for example, it can provide a high level of security to a drone flying at altitudes of 50–100 m over an urban area at an average speed of 4 km/h in conditions of low ambient light; in this scenario, the proposed method can provide a level of security that detects any GPS spoofing attack in which the spoofed location is a distance of 1–4 m (an average of 2.5 m) from the real location.
RODFormer: High-Precision Design for Rotating Object Detection with Transformers
Authors: Dai Yaonan , Yu Jiuyang , Zhang Dean , Hu Tianhao , Zheng Xiaotao
Published: March 2022

Aiming at the problem of Transformers lack of local spatial receptive field and discontinuous boundary loss in rotating object detection, in this paper, we propose a Transformer-based high-precision rotating object detection model (RODFormer). Firstly, RODFormer uses a structured transformer architecture to collect feature information of different resolutions to improve the collection range of feature information. Secondly, a new feed-forward network (spatial-FFN) is constructed. Spatial-FFN fuses the local spatial features of 3 × 3 depthwise separable convolutions with the global channel features of multilayer perceptron (MLP) to solve the deficiencies of FFN in local spatial modeling. Finally, based on the space-FFN architecture, a detection head is built using the CIOU-smooth L1 loss function and only returns to the horizontal frame when the rotating frame is close to the horizontal, so as to alleviate the loss discontinuity of the rotating frame. Ablation experiments of RODFormer on the DOTA dataset show that the Transformer-structured module, the spatial-FFN module and the CIOU-smooth L1 loss function module are all effective in improving the detection accuracy of RODFormer. Compared with 12 rotating object detection models on the DOTA dataset, RODFormer has the highest average detection accuracy (up to 75.60%), that is, RODFormer is more competitive in rotating object detection accuracy.
Discourse, Immigration and the Spanish Press: Critical Analysis of the Discourse on the Ceuta and Melilla Border Incident
Authors: Terrón-Caro Teresa , Cárdenas-Rodríguez Rocío , Ortega-de-Mora Fabiola
Published: March 2022

The Spanish press relayed the events that unfolded during the migratory incident that occurred in Ceuta and Melilla on 17 May 2021. Considering the media’s key role in social and ideological construction, the purpose of this article is to analyze the informative treatment that the Spanish press gave to this incident, contributing to the study of the image that is shown about the migrant population in the media. For this, the present qualitative study performed a critical analysis, using the Atlas software. Ti 8, of the discourse featuring in the newspaper publications of El País, El Mundo, La Vanguardia and ABC. The results demonstrated the following tendencies: a negative-tone discourse; the invisibility of migrant women; and a “we” vs. “them” narrative. In the light of this reality, we suggest that improvements be made, including a shift in the media’s populist discourse and a greater focus on diasporas.
SBL Effectiveness in Teaching Entrepreneurship Skills to Young Immigrant Mothers Head of Household in Colombia: An Experimental Study
Authors: Rico Heidy , Rico Florentino , de la Puente Mario , De Oro Carlos , Lugo Elkyn
Published: March 2022

This article analyses the perception of the effectiveness of the Simulation-Based Learning method in enhancing entrepreneurship skills and academic performance in 78 young immigrant mothers head of household in Colombia in an entrepreneurship course titled Youth and Entrepreneurship. A Wilcoxon signed rank test, and a Kendall Tau correlation coefficient were used to analyze the perceptions and academic performance from the sample studied during a five-month period. A pre-test, post-test, and achievement of academic objectives questionnaire were applied, as well as a verification test of previous knowledge and a focus group at the end of the entrepreneurship course. It was found that SBL enhance the Planning and Management Skills and the Communication Skill and does not fulfill all the course objectives. This study contributes to the analysis of the effectiveness of unconventional teaching methods in different socioeconomic contexts.
Social Innovation Governance in Smart Specialisation Policies and Strategies Heading towards Sustainability: A Pathway to RIS4?
Authors: Meyer Christopher
Published: March 2022

(1) Background: Regional Innovation Strategies on Smart Specialisation (RIS3) receive higher attention due to the start of the new European funding period 2021–2027. Compared to the previous period, RIS3 will focus more attention towards social needs and challenges in their design and implementation to commit themselves towards sustainable regional development and contribute to the European Green Deal and UN Sustainable Development Goals. Nevertheless, RIS3 as innovation policy has not yet incorporated social innovation concepts or socio-ecological demands on its pathway within the constant transition of Europe’s society to become more sustainable. (2) Methods: A systematic literature review has been conducted to identify key insights and gaps in existing literature. (3) Results: The review exposed clustering as a policy tool for sustainable development, a lack of integration of social capital and regional assets to RIS3 design to overcome societal challenges and missing political capabilities to utilize social innovation governances under RIS3 towards sustainability. (4) Conclusions: Future research should pick up these gaps to contribute to a better understanding of social innovators in designing RIS3, meeting social needs and forging the pathway towards sustainability.
Enhanced Potency and Persistence of Immunity to Varicella-Zoster Virus Glycoprotein E in Mice by Addition of a Novel BC02 Compound Adjuvant
Authors: Li Junli , Fu Lili , Yang Yang , Wang Guozhi , Zhao Aihua
Published: March 2022

Herpes zoster (HZ) is one of two distinct syndromes caused by Varicella-zoster virus (VZV). A primary infection with VZV causes varicella in susceptible young children. After resolution of the primary infection, VZV establishes a lifelong latency within the cranial or dorsal root ganglia. With increasing age, family history of shingles, immunosuppression or other risk factors, there is a decline in the virus-specific T-cell-mediated immune (CMI) response which allows reactivation of latent VZV in the root ganglia resulting in HZ. There are currently two vaccines that have been approved to prevent HZ and postherpetic neuralgia (PHN) but one is a live attenuated vaccine, the protective effect of which is considered to decrease significantly with the age of the recipient. However, a recombinant subunit vaccine may provide targeted VZV-specific cellular and humoral immunity, giving it a more potent and longer-lasting protective effect against HZ. The current study reports the development of a novel adjuvant, BC02 (BCG CpG DNA compound adjuvants system 02), composed of Al(OH)3 inorganic salt adjuvant and BC01 (BCG CpG DNA compound adjuvants system 01), a Toll-like receptor 9 (TLR9) agonist. Immunogenicity and compatibility with recombinant VZV glycoprotein E (gE) in mice were studied. The BC02-adjuvanted gE experimental vaccine was highly effective in eliciting both humoral and cellular immune responses to the recombinant gE glycoprotein and VZV-Oka in a mouse model. The efficient production and long-term persistence of gE and VZV-Oka-specific IFN-γ, IL-2-specific T cells and memory B cells in the early (1W), middle (7W), middle-late (15W), and final (27W) immune stages were established. Results of fluorescent antibody to membrane antigen (FAMA) and serum antibody plaque reduction tests also showed that the BC02 adjuvanted-gE experimental vaccine induced mice to secrete neutralizing antibodies against clinically isolated VZV strains. In combination, the current data suggest that the BC02 compound adjuvant offers a strategy to induce an appropriately strong cellular and humoral immunity against the VZV gE protein subunit to improve vaccine efficacy.
COVID-19 Vaccination of Individuals with Down Syndrome—Data from the Trisomy 21 Research Society Survey on Safety, Efficacy, and Factors Associated with the Decision to Be Vaccinated
Authors: Hüls Anke , Feany Patrick T. , Zisman Sophia Isabella , Costa Alberto C. S. , Dierssen Mara , Balogh Robert , Bargagna Stefania , Baumer Nicole T. , Brandão Ana Claudia , Carfi Angelo , Chicoine Brian Allen , Ghosh Sujay , Lakhanpaul Monica , Levin Johannes , Lunsky Yona , Manso Coral , Okun Eitan , Real de Asua Diego , Rebillat Anne-Sophie , Rohrer Tilman R. , Sgandurra Giuseppina , Valentini Diletta , Sherman Stephanie L. , Strydom Andre ,   on behalf of the Trisomy 21 Research Society COVID-19 Initiative
Published: March 2022

Individuals with Down syndrome (DS) are among the groups with the highest risk for severe COVID-19. Better understanding of the efficacy and risks of COVID-19 vaccines for individuals with DS may help improve uptake of vaccination. The T21RS COVID-19 Initiative launched an international survey to obtain information on safety and efficacy of COVID-19 vaccines for individuals with DS. De-identified survey data collected between March and December 2021 were analyzed. Of 2172 individuals with DS, 1973 (91%) had received at least one vaccine dose (57% BNT162b2), 107 (5%) were unvaccinated by choice, and 92 (4%) were unvaccinated for other reasons. Most participants had either no side effects (54%) or mild ones such as pain at the injection site (29%), fatigue (12%), and fever (7%). Severe side effects occurred in <0.5% of participants. About 1% of the vaccinated individuals with DS contracted COVID-19 after vaccination, and all recovered. Individuals with DS who were unvaccinated by choice were more likely to be younger, previously recovered from COVID-19, and also unvaccinated against other recommended vaccines. COVID-19 vaccines have been shown to be safe for individuals with DS and effective in terms of resulting in minimal breakthrough infections and milder disease outcomes among fully vaccinated individuals with DS.
Neutralizing Antibodies Responses against SARS-CoV-2 in a Sardinian Cohort Group Up to 9 Months after BNT162b2 Vaccination
Authors: Sanna Giuseppina , Marongiu Alessandra , Firinu Davide , Piras Cristina , Franci Gianluigi , Galdiero Massimiliano , Pala Giuseppe , Palmas Vanessa , Angius Fabrizio , Littera Roberto , Perra Andrea , Orrù Germano , Campagna Marcello , Costanzo Giulia , Meloni Federico , Coghe Ferdinando , Chessa Luchino , Manzin Aldo
Published: March 2022

Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, has caused over 460 million cases of infection and over 6 million deaths worldwide. The pandemic has called for science, technology, and innovation to provide solutions and, due to an incredible scientific and financial global effort, several prophylactic and therapeutic apparatuses such as monoclonal antibodies and vaccines were developed in less than one year to address this emergency. After SARS-CoV-2 infection, serum neutralizing antibodies are produced by B cells and studies on virus-neutralizing antibodies’ kinetics are pivotal. The process of protective immunity and the duration of this kind of protection against COVID-19 remain to be clarified. We tested 136 sera from 3 groups of individuals, some of them providing multiple sequential sera (1—healthy, no previous CoV2-infected, vaccinated; 2—healthy, previous CoV2 infected, vaccinated; 3—healed, previous CoV2-infected, not vaccinated) to assess the kinetics of antibodies (Abs) neutralizing activity. We found that SARS-CoV-2 infection elicits moderate neutralizing antibody activity in most individuals; neither age nor gender appear to have any influence on Abs responses. The BNT162b2 vaccine, when administered in two doses, induces high antibodies titre endowed with potent neutralizing activity against bare SARS-CoV-2 in in vitro neutralizing assay. The residual neutralization capability and the kinetic of waning immunity were also evaluated over 9 months after the second dose in a reference group of subjects. Neutralization titre showed a decline in all subjects and the median level of S-protein IgG, over 270 days after the second vaccination dose, was below 10 AU/mL in 53% of serum tested.