bluuebunny/crossref_metadata_2025 huggingface dataset:
Biological Behavior of Xenogenic Scaffolds in Alcohol-Induced Rats: Histomorphometric and Picrosirius Red Staining Analysis
Authors: Nogueira Dayane Maria Braz , Figadoli André Luiz de Faria , Alcantara Patrícia Lopes , Pomini Karina Torres , Santos German Iris Jasmin , Reis Carlos Henrique Bertoni , Rosa Júnior Geraldo Marco , Rosso Marcelie Priscila de Oliveira , Santos Paulo Sérgio da Silva , Zangrando Mariana Schutzer Ragghianti , Pereira Eliana de Souza Bastos Mazuqueli , Marchi Miguel Ângelo de , Trazzi Beatriz Flavia de Moraes , Rossi Jéssica de Oliveira , Salmeron Samira , Pastori Cláudio Maldonado , Buchaim Daniela Vieira , Buchaim Rogerio Leone
Published: February 2022

In this experimental protocol, the objective was to evaluate the biological behavior of two xenogenic scaffolds in alcohol-induced rats through histomorphometric and Picrosirius Red staining analysis of non-critical defects in the tibia of rats submitted or not to alcohol ingestion at 25% v/v. Eighty male rats were randomly divided into four groups (n = 20 each): CG/B (water diet + Bio-Oss® graft, Geistlich Pharma AG, Wolhusen, Switzerland), CG/O (water diet + OrthoGen® graft, Baumer, Mogi Mirim, Brazil), AG/B (25% v/v alcohol diet + Bio-Oss® graft), and AG/O (25% v/v alcohol diet + OrthoGen® graft). After 90 days of liquid diet, the rats were surgically obtained, with a defect in the tibia proximal epiphysis; filled in according to their respective groups; and euthanized at 10, 20, 40 and 60 days. In two initial periods (10 and 20 days), all groups presented biomaterial particles surrounded by disorganized collagen fibrils. Alcoholic animals (AG/B and AG/O) presented, in the cortical and medullary regions, a reactive tissue with inflammatory infiltrate. In 60 days, in the superficial area of the surgical cavities, particles of biomaterials were observed in all groups, with new compact bone tissue around them, without complete closure of the lesion, except in non-alcoholic animals treated with Bio-Oss® xenograft (CG/B), where the new cortical interconnected the edges of the defect. Birefringence transition was observed in the histochemical analysis of collagen fibers by Picrosirius Red, in which all groups in periods of 10 and 20 days showed red-orange birefringence, and from 40 days onwards greenish-yellow birefringence, which demonstrates the characteristic transition from the formation of thin and disorganized collagen fibers initially to more organized and thicker later. In histomorphometric analysis, at 60 days, CG/B had the highest volume density of new bone (32.9 ± 1.15) and AG/O the lowest volume density of new bone (15.32 ± 1.71). It can be concluded that the bone neoformation occurred in the defects that received the two biomaterials, in all periods, but the Bio-Oss® was superior in the results, with its groups CG/B and AG/B displaying greater bone formation (32.9 ± 1.15 and 22.74 ± 1.15, respectively) compared to the OrthoGen® CG/O and AG/O groups (20.66 ± 2.12 and 15.32 ± 1.71, respectively), and that the alcoholic diet interfered negatively in the repair process and in the percentage of new bone formed.
A Critical Review on Wood-Based Polymer Composites: Processing, Properties, and Prospects
Authors: Ramesh Manickam , Rajeshkumar Lakshminarasimhan , Sasikala Ganesan , Balaji Devarajan , Saravanakumar Arunachalam , Bhuvaneswari Venkateswaran , Bhoopathi Ramasamy
Published: February 2022

Waste recycling is one of the key aspects in current day studies to boost the country’s circular economy. Recycling wood from construction and demolished structures and combining it with plastics forms wood-polymer composites (WPC) which have a very wide scope of usage. Such recycled composites have very low environmental impact in terms of abiotic potential, global warming potential, and greenhouse potential. Processing of WPCs can be easily done with predetermined strength values that correspond to its end application. Yet, the usage of conventional polymer composite manufacturing techniques such as injection molding and extrusion has very limited scope. Many rheological characterization techniques are being followed to evaluate the influence of formulation and process parameters over the quality of final WPCs. It will be very much interesting to carry out a review on the material formulation of WPCs and additives used. Manufacturing of wood composites can also be made by using bio-based adhesives such as lignin, tannin, and so on. Nuances in complete replacement of synthetic adhesives as bio-based adhesives are also discussed by various researchers which can be done only by complete understanding of formulating factors of bio-based adhesives. Wood composites play a significant role in many non-structural and structural applications such as construction, floorings, windows, and door panels. The current review focuses on the processing of WPCs along with additives such as wood flour and various properties of WPCs such as mechanical, structural, and morphological properties. Applications of wood-based composites in various sectors such as automotive, marine, defense, and structural applications are also highlighted in this review.
Fresh Properties and Sulfuric Acid Resistance of Sustainable Mortar Using Alkali-Activated GGBS/Fly Ash Binder
Authors: Mohamed Osama Ahmed , Al Khattab Rania
Published: February 2022

In this study, sorptivity, setting time, resistance to sulfuric acid, and compressive strength of mortars that use alkali-activated GGBS and fly ash as binders, were evaluated experimentally. The activation of binders, was achieved at room temperature of 22 ± 2 °C using combinations of sodium silicates (Na2SiO3) and sodium hydroxide (NaOH) solutions in ratios of 1.5, 2.0, and 2.5. The parameters considered in terms of their effects on fresh and hardened properties include: NaOH molarity, activator ratio Na2SiO3/NaOH, mortar sample age, and relative amount of GGBS/fly ash in binder combination. Sorptivity, change in mass, and compressive strength were determined for mortar samples that were submerged in 10% sulfuric acid solution for 7 days, 28 days, and 90 days. The binder for mortar samples tested at each of the specified ages consisted of 100% GGBS (G100), 75%GGBS+25% fly ash (G75F25), or 50% GGBS + 50% fly ash (G50F50). The binder was activated using Na2SiO3 solution, combined with 10 M, 12 M, 14 M, or 16 M NaOH solution. It was found that sorptivity decreases with increase in curing age, for all activator ratios, concentrations, and relative amounts of GGBS/fly ash. Binder consisting of 75%GGBS + 25% fly ash with NaOH concentration of 12 M had the lowest sorptivity. Exposure of alkali-activated GGBS/fly ash mortar samples to sulfate attack did not cause loss in mass nor visible signs of damage/deterioration. All binder combinations experienced increase in compressive strength after curing in 10%sufluric acid solution, with the optimum G75F25 mix achieving a 28-day strength of 80.53 MPa when NaOH molarity is 10 M, which increased to 91.06 MPa after 90 days. Variation in concentration of NaOH didn’t cause significant change in the magnitudes of 28-day or 90-day compressive strengths of G50F50. However, despite slow dissolution of fly ash and immersion in 10% sulfuric acid solution, G50F50 developed 28-day compressive strength of 56.23 MPa and 90-day compressive of 86.73 MPa, which qualifies G50F50 as high strength mortar for practical purposes.
Elastic Correlative Least-Squares Reverse Time Migration Based on Wave Mode Decomposition
Authors: Zheng Yue , Liu Youshan , Xu Tao , Li Zhiyuan
Published: February 2022

The conventional elastic least-squares reverse time migration (LSRTM) generally inverts the parameter perturbation of the model rather than the reflectivity of reflected P- and S-modes, which leads to difficulty in directly interpreting the physical properties of the subsurface media. However, an accurate velocity model that is needed by the separation of seismic records of conventional LSRTM is usually unavailable in real data, which limits its application. In this study, we introduce a new practical correlative LSRTM (CLSRTM) scheme based on wave mode decomposition without amplitude and phase distortion, which frees from separation of seismic records. In this study, we deduced the migration and the de-migration operators using the decoupled P- and S-wave equations in heterogeneous media, which needs no extra wavefield decomposition in simulated data. To accelerate the convergence and improve the efficiency of the inversion, we adopted an analytical step-length formula that can be incidentally computed during the necessary de-migration process and the L-BFGS algorithm. Two numerical examples demonstrate that the proposed method can compensate the energy of deep structures, and generate clear images with balanced amplitudes and enhanced resolution even for the fault structures beneath the salt dome.
Molecular Simulation Comparison of Two Ultrafine Coal-Based Activated Carbons for the Removal of Methylene Blue from Water
Authors: Zhu Zaisheng , Shen Liang , Liu Yin , Wang Chuanzhen , Zhu Hongzheng , Shao Huaizhi , Zhu Jinbo
Published: February 2022

Coal-based activated carbons (CACs) have excellent valuable applications, and have been industrially produced. However, ultra-fine coal-based activated carbons (UCACs) and their removal of methylene blue (MB) have rarely been reported in the present literature. Two kinds of UCACs were obtained in this paper and the adsorption test of MB was carried out. The adsorption performance of MB on UCAC was simulated by Grand Canonical Monte Carlo (GC-MC) method. The experimental results were validated by molecular simulation, and the adsorption mechanism was investigated. The adsorption amount of MB, the d50, and specific surface area values of the UCACnew (obtained by the new method) and UCACcm (obtained by the conventional chemical method) were 746.95 mg/g, 12.54 μm, 1225.36 m2/g and 652.77 mg/g, 12.10 μm, 713.76 m2/g, respectively. The results of the molecular simulation calculations were consistent with the pattern of magnitude of the experimental results. The peak of the adsorption concentration occurred near 6 Å on the pore surface. The interaction energy of MB molecules with carboxyl groups was much larger than with hydroxyl groups. Van der Waals forces dominated the adsorption process, with a contribution of >60% in both cases.
Machine Learning Approaches for Discriminating Bacterial and Viral Targeted Human Proteins
Authors: Barman Ranjan Kumar , Mukhopadhyay Anirban , Maulik Ujjwal , Das Santasabuj
Published: February 2022

Infectious diseases are one of the core biological complications for public health. It is important to recognize the pathogen-specific mechanisms to improve our understanding of infectious diseases. Differentiations between bacterial- and viral-targeted human proteins are important for improving both prognosis and treatment for the patient. Here, we introduce machine learning-based classifiers to discriminate between the two groups of human proteins. We used the sequence, network, and gene ontology features of human proteins. Among different classifiers and features, the deep neural network (DNN) classifier with amino acid composition (AAC), dipeptide composition (DC), and pseudo-amino acid composition (PAAC) (445 features) achieved the best area under the curve (AUC) value (0.939), F1-score (94.9%), and Matthews correlation coefficient (MCC) value (0.81). We found that each of the selected top 100 of the bacteria- and virus-targeted human proteins from a candidate pool of 1618 and 3916 proteins, respectively, were part of distinct enriched biological processes and pathways. Our proposed method will help to differentiate between the bacterial and viral infections based on the targeted human proteins on a global scale. Furthermore, identification of the crucial pathogen targets in the human proteome would help us to better understand the pathogen-specific infection strategies and develop novel therapeutics.
Rye Flour and Rye Bran: New Perspectives for Use
Authors: Dziki Dariusz
Published: February 2022

Rye (Secale cereale L.) is abundantly cultivated in countries like Europe and North America, particularly in regions where soil and climate conditions are unfavorable for the growth of other cereals. Among all the cereals generally consumed by human beings, rye grains are characterized by the presence of the highest content of fiber. They are also a rich source of many phytochemical compounds, which are mainly distributed in the outer parts of the grain. This review focuses on the current knowledge regarding the characteristics of rye bran and wholemeal rye flour, as well as their applications in the production of both food and nonfood products. Previous studies have shown that the physicochemical properties of ground rye products are determined by the type of milling technique used to grind the grains. In addition, the essential biologically active compounds found in rye grains were isolated and characterized. Subsequently, the possibility of incorporating wholemeal rye flour, rye bran, and other compounds extracted from rye bran into different industrial products is discussed.
Brine and Post-Frying Oil Management in the Fish Processing Industry—A Concept Based on Oleaginous Yeast Culture
Authors: Fabiszewska Agata , Wierzchowska Katarzyna , Nowak Dorota , Wołoszynowska Małgorzata , Zieniuk Bartłomiej
Published: February 2022

Waste management solutions including the valorization of waste materials in biotechnological processes is an important issue needing to be explored. A significant amount of waste is being generated by the food industry. In this study, an attempt was made to utilize two fish industry wastes simultaneously—waste brine and post-frying oil from frying fish fillets in Yarrowia lipolytica culture with high single cell oil synthesis yield. Oxygenation in the culture medium had a positive effect on the biosynthesis efficiency of microbial oil, resulting in the highest content of lipids in yeast cells at the level of 0.431 g/g d.m (dry mass). Y. lipolytica yeast preferentially accumulated oleic acid and linoleic acid, and the high content of linolenic acid, valuable from a nutritional point of view, was also found in microbial oil. This study proved that the use of post-frying rapeseed oil gives a chance to obtain valuable storage lipids in Y. lipolytica yeast cells via ex novo biosynthesis pathway. Furthermore, the wastewater stream could be limited using a waste brine as a solvent in medium preparation, but the brine share should not exceed 30% so as not to inhibit yeast cell growth.
Interfacial Microstructure and Mechanical Reliability of Sn-58Bi/ENEPIG Solder Joints
Authors: Chen Cheng , Wang Cheng , Sun Huhao , Yin Hongbo , Gao Xiuli , Xue Hengxu , Ni Dahai , Bian Kan , Gu Qilin
Published: February 2022

The 42 wt.% Sn–58 wt.% Bi (Sn-58Bi) Ball Grid Array (BGA) solder balls were mounted to electroless nickel-electroless palladium-immersion gold (ENEPIG) pads by employing the reflow process profile. The effects of reflow cycles and aging time on the interfacial microstructure and growth behavior of intermetallic compounds, as well as the mechanical properties, were investigated. Pd-Au-Sn intermetallic compound (IMC) was formed at the Sn-58Bi/ENEPIG interface. With the increase in reflow cycles and aging time, the IMC grew gradually. After five reflow cycles, the shear strength of the Sn-58Bi/ENEPIG solder joints first decreased and then increased. After 500 h of aging duration under −40 °C, the shear strength of the Sn-58Bi/ENEPIG solder joints decreased by about 12.3%. The fracture mode transferred from ductile fracture to ductile and brittle mixed fracture owing to the fact that the fracture location transferred from the solder matrix to the IMC interface with the increase in reflow cycles and aging time.
A Late Holocene Stable Isotope and Carbon Accumulation Record from Teringi Bog in Southern Estonia
Authors: Stansell Nathan D. , Klein Eric S. , Hill Kristyn , Terasmaa Jaanus , Dodd Justin , Boes Maxwell , Eensalu Mariliis , Fortney Carolyn , Fritts Annabella , Garcia Roxana , Price Brittany , Swanson Brandy
Published: February 2022

Radiocarbon-dated peat cores collected from an ombrotrophic bog in southern Estonia record shifting environmental conditions and carbon accumulation rates in northern Europe during the late Holocene. Modern observations indicate that the water balance of the peatland is highly influenced by changes in relative humidity, followed by temperature and precipitation. The modern δ18O and δ2H values of surface water suggest that the groundwater is an integration of several months of precipitation. There also appears to be little or no direct influence of surface evaporation on the water within the bog, suggesting that water loss is preferentially through transpiration and sub-surface flow. Bulk peat δ13C values exhibit a trend of higher values through the late Holocene, suggesting a pattern of overall increased surface wetness. The δ15N values were low from ~4130 to 3645 cal yr BP, suggesting drier conditions, followed by intermediate values until ~2995 cal yr BP. The δ15N values decrease again from ~2995 to 2470 cal yr BP, suggesting a return to drier conditions, followed by intermediate values until ~955 cal yr BP. The δ15N values were high, suggesting wetter conditions from ~955 to 250 cal yr BP, followed by intermediate values through the modern. Carbon accumulation rates were low to intermediate from ~4200 to 2470 cal yr BP, followed by intermediate-to-high values until ~1645 cal yr BP. Carbon accumulation rates were then low until ~585 cal yr BP, followed by intermediate values through the modern. The geochemical data, combined with observed changes in peat composition and regional proxies of temperature and water table fluctuations through the late Holocene, suggest that carbon accumulation rates were relatively low under dry and warm conditions, whereas accumulation was generally higher (up to ~80 g C m−2 yr−1) when the climate was wetter and/or colder. These findings further suggest that future environmental changes affecting the regional water balance and temperature will impact the potential for northern peatlands to capture and store carbon.
Preimplantation Endometrial Transcriptomics in Natural Conception Cycle of the Rhesus Monkey
Authors: Bhat Muzaffer , Khan Meraj , Lalitkumar P.G.L. , Poorasamy Jeevitha , Sengupta Jayasree , Ghosh Debabrata
Published: February 2022

There is no report on preimplantation phase endometrial transcriptomics in natural conception cycles of primates. In the present study, the whole-genome expression array of endometrium on Days 2, 4, and 6 post-ovulation (pov) in proven natural conception (Group 1; n = 12) and non-mated, ovulatory (Group 2; n = 12) cycles of rhesus monkeys was examined, compared, and validated. Of fifteen (15) genes showing differential expression (>2-fold; pFDR < 0.05), six genes (CHRND, FOXD3, GJD4, MAPK8IP3, MKS1, and NUP50) were upregulated, while eight genes (ADCY5, ADIPOR1, NNMT, PATL1, PIGV, TGFBR2, TOX2, and VWA5B1) were down regulated on Day 6 pov as compared to Day 2 pov in conception cycles. On Day 6 pov, four genes (ADCY5, NNMT, TOX2, and VWA5B1) were down regulated, and AVEN was upregulated in conception cycles compared with the non-conception cycle. These observations were orthogonally validated at protein expression level. Group-specifically expressed unique genes in conception cycles influence the process of induction of immune-tolerance, while the genes expressed in both groups influence processes of protein targeting and metabolism. A triad of timed-actions of progesterone, seminal plasma, and preimplantation embryo putatively regulate several input molecules to CREB, NF-kB, and STAT regulatory networks during secretory phase towards evolution of endometrial receptivity in the rhesus monkey.
RFI Suppression for SAR via a Dictionary-Based Nonconvex Low-Rank Minimization Framework and Its Adaptive Implementation
Authors: Tang Zhouyang , Deng Yunkai , Zheng Huifang
Published: February 2022

Synthetic aperture radar (SAR) frequently suffers from radio frequency interference (RFI) due to the simultaneous presence of numerous wireless communication signals. Recently, the narrowband RFI is found to possess the low-rank property benefiting from stable frequency occupancy, hence the reconsideration of RFI suppression as a joint sparse and low-rank optimization problem. The existing methods either use the non-sparse useful signal itself as the sparse regularizer, or employ the nuclear norm to approximate the rank function, which punishes all singular values with the same penalty via singular value thresholding (SVT), resulting in the improper punishment problem. Hence, both are consequentially subject to performance limitation. In this paper, a novel dictionary-based nonconvex low-rank minimization (DNLRM) optimization framework is proposed for RFI suppression, which concurrently considers the improvements for both the sparse regularizer and the low-rank regularizer. For the former, an over-completed dictionary is constructed, for which the sparse coefficient acts as the sparse regularizer. For the latter, the rank function is more accurately approximated by innovatively introducing the nonconvex function, for which the supergradient is synchronously used to generate the weighted penalty, thus solving the improper punishment problem. The derivation of the closed-form solution and the convergence analysis are described in detail. Additionally, the adaptive selection scheme for the model parameter is uniquely proposed for further ensuring the practicality of the DNLRM framework. The superiority of the proposed method is demonstrated via not only the RFI-free real SAR data combined with the measured RFI, but the RFI-contaminated real SAR data.
Effects of Climate Change on Vegetation Growth in the Yellow River Basin from 2000 to 2019
Authors: Ren Yanqun , Liu Jinping , Liu Suxia , Wang Zhonggen , Liu Tie , Shalamzari Masoud Jafari
Published: February 2022

A changing climate has been posing significant impacts on vegetation growth, especially in the Yellow River Basin (YRB) where agriculture and ecosystems are extremely vulnerable. In this study, the data for normalized difference vegetation index (NDVI) obtained from moderate-resolution imaging spectroradiometer (MODIS) sensors and climate data (precipitation and temperature) derived from the national meteorological stations were employed to examine the spatiotemporal differences in vegetation growth and its reaction to climate changes in the YRB from 2000–2019, using several sophisticated statistical methods. The results showed that both NDVI and climatic variables exhibited overall increasing trends during this period, and positive correlations at different significant levels were found between temperature/precipitation and NDVI. Furthermore, NDVI in spring had the strongest response to temperature/precipitation, and the correlation coefficient of NDVI with temperature and precipitation was 0.485 and 0.726, respectively. However, an opposite situation was detected in autumn (September to November) since NDVIs exhibited the weakest responses to temperatures/precipitation, and the NDVI’s correlation with both temperature and precipitation was 0.13. This indicated that, compared to other seasons, increasing the temperature and precipitation has the most significant effect on NDVI in spring (March to May). Except for a few places in the northern, southern, and southwestern regions of the YRB, NDVI was positively correlated with precipitation in most areas. There was an inverse relationship between NDVI and temperature in most parts of the central YRB, especially in summer (June to August) and growing season (May to September); however, there was a positive correlation in most areas of the YRB in spring. Finally, continuous attention must be given to the influence of other factors in the YRB.
Active Fire Mapping on Brazilian Pantanal Based on Deep Learning and CBERS 04A Imagery
Authors: Higa Leandro , Marcato Junior José , Rodrigues Thiago , Zamboni Pedro , Silva Rodrigo , Almeida Laisa , Liesenberg Veraldo , Roque Fábio , Libonati Renata , Gonçalves Wesley Nunes , Silva Jonathan
Published: February 2022

Fire in Brazilian Pantanal represents a serious threat to biodiversity. The Brazilian National Institute of Spatial Research (INPE) has a program named Queimadas, which estimated from January 2020 to October 2020, a burned area in Pantanal of approximately 40,606 km2. This program also provides daily data of active fire (fires spots) from a methodology that uses MODIS (Aqua and Terra) sensor data as reference satellites, which presents limitations mainly when dealing with small active fires. Remote sensing researches on active fire dynamics have contributed to wildfire comprehension, despite generally applying low spatial resolution data. Convolutional Neural Networks (CNN) associated with high- and medium-resolution remote sensing data may provide a complementary strategy to small active fire detection. We propose an approach based on object detection methods to map active fire in the Pantanal. In this approach, a post-processing strategy is adopted based on Non-Max Suppression (NMS) to reduce the number of highly overlapped detections. Extensive experiments were conducted, generating 150 models, as five-folds were considered. We generate a public dataset with 775-RGB image patches from the Wide Field Imager (WFI) sensor onboard the China Brazil Earth Resources Satellite (CBERS) 4A. The patches resulted from 49 images acquired from May to August 2020 and present a spatial and temporal resolutions of 55 m and five days, respectively. The proposed approach uses a point (active fire) to generate squared bounding boxes. Our findings indicate that accurate results were achieved, even considering recent images from 2021, showing the generalization capability of our models to complement other researches and wildfire databases such as the current program Queimadas in detecting active fire in this complex environment. The approach may be extended and evaluated in other environmental conditions worldwide where active fire detection is still a required information in fire fighting and rescue initiatives.
Monitoring Post-Flood Recovery of Croplands Using the Integrated Sentinel-1/2 Imagery in the Yangtze-Huai River Basin
Authors: Li Miao , Zhang Tao , Tu Ying , Ren Zhehao , Xu Bing
Published: February 2022

The increasingly frequent flooding imposes tremendous and long-lasting damages to lives and properties in impoverished rural areas. Rapid, accurate, and large-scale flood mapping is urgently needed for flood management, and to date has been successfully implemented benefiting from the advancement in remote sensing and cloud computing technology. Yet, the effects of agricultural emergency response to floods have been limitedly evaluated by satellite-based remote sensing, resulting in biased post-flood loss assessments. Addressing this challenge, this study presents a method for monitoring post-flood agricultural recovery using Sentinel-1/2 imagery, tested in three flood-affected main grain production areas, in the middle and lower Yangtze and Huai River, China. Our results indicated that 33~72% of the affected croplands were replanted and avoided total crop failures in summer 2020. Elevation, flood duration, crop rotation scheme, and flooding emergency management affect the post-flood recovery performance. The findings also demonstrate rapid intervention measures adjusted to local conditions could reduce the agricultural failure cost from flood disasters to a great extent. This study provides a new alternative for comprehensive disaster loss assessment in flood-prone agricultural regions, which will be insightful for worldwide flood control and management.
First Gradually, Then Suddenly: Understanding the Impact of Image Compression on Object Detection Using Deep Learning
Authors: Gandor Tomasz , Nalepa Jakub
Published: February 2022

Video surveillance systems process high volumes of image data. To enable long-term retention of recorded images and because of the data transfer limitations in geographically distributed systems, lossy compression is commonly applied to images prior to processing, but this causes a deterioration in image quality due to the removal of potentially important image details. In this paper, we investigate the impact of image compression on the performance of object detection methods based on convolutional neural networks. We focus on Joint Photographic Expert Group (JPEG) compression and thoroughly analyze a range of the performance metrics. Our experimental study, performed over a widely used object detection benchmark, assessed the robustness of nine popular object-detection deep models against varying compression characteristics. We show that our methodology can allow practitioners to establish an acceptable compression level for specific use cases; hence, it can play a key role in applications that process and store very large image data.
A Dynamic Four-Step Data Security Model for Data in Cloud Computing Based on Cryptography and Steganography
Authors: Adee Rose , Mouratidis Haralambos
Published: February 2022

Cloud computing is a rapidly expanding field. It allows users to access computer system resources as needed, particularly data storage and computational power, without managing them directly. This paper aims to create a data security model based on cryptography and steganography for data in cloud computing that seeks to reduce existing security and privacy concerns, such as data loss, data manipulation, and data theft. To identify the problem and determine its core cause, we studied various literature on existing cloud computing security models. This study utilizes design science research methodology. The design science research approach includes problem identification, requirements elicitation, artifact design and development, demonstration, and assessment. Design thinking and the Python programming language are used to build the artifact, and discussion about its working is represented using histograms, tables, and algorithms. This paper’s output is a four-step data security model based on Rivest–Shamir–Adleman, Advanced Encryption Standard, and identity-based encryption algorithms alongside Least Significant Bit steganography. The four steps are data protection and security through encryption algorithms, steganography, data backup and recovery, and data sharing. This proposed approach ensures more cloud data redundancy, flexibility, efficiency, and security by protecting data confidentiality, privacy, and integrity from attackers.
Development of a Low-Cost 6 DOF Brick Tracking System for Use in Advanced Gas-Cooled Reactor Model Tests
Authors: Olson Paolo , Crewe Adam J. , Gokce Tansu , Horseman Tony , White Rory E.
Published: February 2022

This paper presents the design of a low-cost, compact instrumentation system to enable six degree of freedom motion tracking of acetal bricks within an experimental model of a cracked Advanced Gas-Cooled Reactor (AGR) core. The system comprises optical and inertial sensors and capitalises on the advantages offered by data fusion techniques. The optical system tracks LED indicators, allowing a brick to be accurately located even in cluttered images. The LED positions are identified using a geometrical correspondence algorithm, which was optimised to be computationally efficient for shallow movements, and complex camera distortions are corrected using a versatile Incident Ray-Tracking calibration. Then, a Perspective-Ray-based Scaled Orthographic projection with Iteration (PRSOI) algorithm is applied to each LED position to determine the six degree of freedom pose. Results from experiments show that the system achieves a low Root Mean Squared (RMS) error of 0.2296 mm in x, 0.3943 mm in y, and 0.0703 mm in z. Although providing an accurate measurement solution, the optical tracking system has a low sample rate and requires the line of sight to be maintained throughout each test. To increase the robustness, accuracy, and sampling frequency of the system, the optical system can be augmented with an Inertial Measurement Unit (IMU). This paper presents a method to integrate the optical system and IMU data by accurately timestamping data from each set of sensors and aligning the two coordinate axes. Once miniaturised, the developed system will be used to track smaller components within the AGR models that cannot be tracked with current instrumentation, expanding reactor core modelling capabilities.
Study of the Off-Axis Fresnel Zone Plate of a Microscopic Tomographic Aberration
Authors: Yang Lin , Ma Zhenyu , Liu Siqi , Jiao Qingbin , Zhang Jiahang , Zhang Wei , Pei Jian , Li Hui , Li Yuhang , Zou Yubo , Xu Yuxing , Tan Xin
Published: February 2022

A tomographic microscopy system can achieve instantaneous three-dimensional imaging, and this type of microscopy system has been widely used in the study of biological samples; however, existing chromatographic microscopes based on off-axis Fresnel zone plates have degraded image quality due to geometric aberrations such as spherical aberration, coma aberration, and image scattering. This issue hinders the further development of chromatographic microscopy systems. In this paper, we propose a method for the design of an off-axis Fresnel zone plate with the elimination of aberrations based on double exposure point holographic surface interference. The aberration coefficient model of the optical path function was used to solve the optimal recording parameters, and the principle of the aberration elimination tomography microscopic optical path was verified. The simulation and experimental verification were carried out utilizing a Seidel coefficient, average gradient, and signal-to-noise ratio. First, the aberration coefficient model of the optical path function was used to solve the optimal recording parameters. Then, the laminar mi-coroscopy optical system was constructed for the verification of the principle. Finally, the simulation calculation results and the experimental results were verified by comparing the Seidel coefficient, average gradient, and signal-to-noise ratio of the microscopic optical system before and after the aberration elimination. The results show that for the diffractive light at the orders 0 and ±1, the spherical aberration W040 decreases by 62–70%, the coma aberration W131 decreases by 96–98%, the image dispersion W222 decreases by 71–82%, and the field curvature W220 decreases by 96–96%, the average gradient increases by 2.8%, and the signal-to-noise ratio increases by 18%.
Interictal Spike and Loss of Hippocampal Theta Rhythm Recorded by Deep Brain Electrodes during Epileptogenesis
Authors: Fu Xiaoxuan , Wang Youhua , Belkacem Abdelkader Nasreddine , Cao Yingxin , Cheng Hao , Zhao Xiaohu , Chen Shenghua , Chen Chao
Published: February 2022

Epileptogenesis is the gradual dynamic process that progressively led to epilepsy, going through the latent stage to the chronic stage. During epileptogenesis, how the abnormal discharges make theta rhythm loss in the deep brain remains not clear. In this paper, a loss of theta rhythm was estimated based on time–frequency power using the longitudinal electroencephalography (EEG), recorded by deep brain electrodes (e.g., the intracortical microelectrodes such as stereo-EEG electrodes) with monitored epileptic spikes in a rat from the first region in the hippocampal circuit. Deep-brain EEG was collected from the period between adjacent sporadic interictal spikes (lasting 3.56 s—35.38 s) to the recovery period without spikes by videos while the rats were performing exploration. We found that loss of theta rhythm became more serious during the period between adjacent interictal spikes than during the recovery period without spike, and during epileptogenesis, more loss was observed at the acute stage than the chronic stage. We concluded that the emergence of the interictal spike was the direct cause of loss of theta rhythm, and the inhibitory effect of the interictal spike on ongoing theta rhythm was persistent as well as time dependent during epileptogenesis. With the help of the intracortical microelectrodes, this study provides a temporary proof of interictal spikes to produce ongoing theta rhythm loss, suggesting that the interictal spikes could correlate with the epileptogenesis process, display a time-dependent feature, and might be a potential biomarker to evaluate the deficits in theta-related memory in the brain.
Autonomous Quadcopter Landing on a Moving Target
Authors: Gautam Alvika , Singh Mandeep , Sujit Pedda Baliyarasimhuni , Saripalli Srikanth
Published: February 2022

Autonomous landing on a moving target is challenging because of external disturbances and localization errors. In this paper, we present a vision-based guidance technique with a log polynomial closing velocity controller to achieve faster and more accurate landing as compared to that of the traditional vertical landing approaches. The vision system uses a combination of color segmentation and AprilTags to detect the landing pad. No prior information about the landing target is needed. The guidance is based on pure pursuit guidance law. The convergence of the closing velocity controller is shown, and we test the efficacy of the proposed approach through simulations and field experiments. The landing target during the field experiments was manually dragged with a maximum speed of 0.6 m/s. In the simulations, the maximum target speed of the ground vehicle was 3 m/s. We conducted a total of 27 field experiment runs for landing on a moving target and achieved a successful landing in 22 cases. The maximum error magnitude for successful landing was recorded to be 35 cm from the landing target center. For the failure cases, the maximum distance of vehicle landing position from target boundary was 60 cm.
Putting Temperature into the Equation: Development and Validation of Algorithms to Distinguish Non-Wearing from Inactivity and Sleep in Wearable Sensors
Authors: Pagnamenta Sara , Grønvik Karoline Blix , Aminian Kamiar , Vereijken Beatrix , Paraschiv-Ionescu Anisoara
Published: February 2022

Long-term monitoring of real-life physical activity (PA) using wearable devices is increasingly used in clinical and epidemiological studies. The quality of the recorded data is an important issue, as unreliable data may negatively affect the outcome measures. A potential source of bias in PA assessment is the non-wearing of a device during the expected monitoring period. Identification of non-wear time is usually performed as a pre-processing step using data recorded by the accelerometer, which is the most common sensor used for PA analysis algorithms. The main issue is the correct differentiation between non-wear time, sleep time, and sedentary wake time, especially in frail older adults or patient groups. Based on the current state of the art, the objectives of this study were to (1) develop robust non-wearing detection algorithms based on data recorded with a wearable device that integrates acceleration and temperature sensors; (2) validate the algorithms using real-world data recorded according to an appropriate measurement protocol. A comparative evaluation of the implemented algorithms indicated better performances (99%, 97%, 99%, and 98% for sensitivity, specificity, accuracy, and negative predictive value, respectively) for an event-based detection algorithm, where the temperature sensor signal was appropriately processed to identify the timing of device removal/non-wear.
High-Throughput Continuous-Flow Separation in a Micro Free-Flow Electrophoresis Glass Chip Based on Laser Microfabrication
Authors: Zhang Aodong , Xu Jian , Li Xiaolong , Lin Zijie , Song Yunpeng , Li Xin , Wang Zhenhua , Cheng Ya
Published: February 2022

Micro free-flow electrophoresis (μFFE) provides a rapid and straightforward route for the high-performance online separation and purification of targeted liquid samples in a mild manner. However, the facile fabrication of a μFFE device with high throughput and high stability remains a challenge due to the technical barriers of electrode integration and structural design for the removal of bubbles for conventional methods. To address this, the design and fabrication of a high-throughput μFFE chip are proposed using laser-assisted chemical etching of glass followed by electrode integration and subsequent low-temperature bonding. The careful design of the height ratio of the separation chamber and electrode channels combined with a high flow rate of buffer solution allows the efficient removal of electrolysis-generated bubbles along the deep electrode channels during continuous-flow separation. The introduction of microchannel arrays further enhances the stability of on-chip high-throughput separation. As a proof-of-concept, high-performance purification of fluorescein sodium solution with a separation purity of ~97.9% at a voltage of 250 V from the mixture sample solution of fluorescein sodium and rhodamine 6G solution is demonstrated.
GC-MS and SPME-GC/MS Analysis and Bioactive Potential Evaluation of Essential Oils from Two Viola Species Belonging to the V. calcarata Complex
Authors: Vitalini Sara , Iriti Marcello , Garzoli Stefania
Published: February 2022

Viola calcarata L. and Viola dubyana Burnat ex Gremli belong to the V. calcarata complex in Viola section Melanium (Violaceae family). For the first time, the essential oils (EOS) obtained by hydrodistillation from dried flowers, were analyzed by GC/MS and SPME-GC/MS to describe their volatile chemical profile. Differences in the qualitative and quantitative composition between the two violets have been found. A total of 43 compounds were identified among which methyl salicylate was the most abundant (from 45.5 to 68.0%) both in the vapor and liquid phase. The performed bioactivity tests pointed out the greater effect of V. dubyana EO compared to that obtained from V. calcarata. Nevertheless, both EOs proved to be good scavengers, especially toward the ABTS⋅+ radical. They also showed a dose-dependent phytotoxic action against Sinapis alba and Lolium multiflorum. Their seed germination was inhibited up to 100% and 25%, respectively, in response to the highest used dose (100 μL) of each EO. Furthermore, a significant decrease in root and shoot length was observed. The resulting seedling vigor index was reduced by 15–100% and 8–82% for S. alba and by 11–91% and 4–91% for L. multiflorum by V. dubyana and V. calcarata EOS, respectively.
Two New Fumarprotocetraric Acid Lactones Identified and Characterized by UHPLC-PDA/ESI/ORBITRAP/MS/MS from the Antarctic Lichen Cladonia metacorallifera
Authors: Sepúlveda Beatriz , Cornejo Alberto , Bárcenas-Pérez Daniela , Cheel José , Areche Carlos
Published: February 2022

Lichens are symbiotic organisms between algae and fungi, which are makers of secondary compounds named as lichen substances. Hyphenated techniques have significantly helped natural product chemistry, especially UHPLC/ESI/MS/MS in the identification, separation, and tentative characterization of secondary metabolites from natural sources. Twenty-five compounds were detected from the Antarctic lichen Cladonia metacorallifera for the first time using UHPLC-PDA/ESI/Orbitrap/MS/MS. Compounds 5 and 7 are reported as new compounds, based on their MS/MS fragmentation routes, and considered as fumarprotocetraric acid derivatives. Besides, ten known phenolic identified as orsellinic acid, ethyl 4-carboxyorsellinate, psoromic acid isomer, succinprotocetraric acid, siphulellic acid, connorstictic acid, cryptostictic acid, lecanoric acid, lobaric acid and gyrophoric acid are noticed for the first time in the Cladonia genus.
Mechatronics Technology and Transportation Sustainability
Authors: Rassõlkin Anton , Tammi Kari , Demidova Galina , HosseinNia Hassan
Published: February 2022

This editorial introduces a Special Issue (SI) that contains nine chosen articles in Sustainability [...]
Long-Term Climatic Changes in Small Ruminant Farms in Greece and Potential Associations with Animal Health
Authors: Katsarou Eleni I. , Lianou Daphne T. , Papadopoulos Elias , Fthenakis George C.
Published: February 2022

The objectives of this work were (a) to present the changes in climatic parameters from 1989 to 2019, in 444 locations throughout Greece, where small ruminant farms have been based and (b) to present associations of the changes in the climatic parameters with clinical data related to small ruminant health. Climatic variables (1989–2019) were obtained for 444 locations with small ruminant farms throughout Greece. During this period, significant increases were noted in temperature-related parameters (annually 0.05 °C for average temperature and 0.14 °C for temperature range) and precipitation (annually 0.03 mm). There were significant differences in climatic conditions between locations of farms in accord with the management system applied therein, as well as in accord with the breed of animals on the farms (e.g., higher average temperature in locations with Greek breeds, higher temperature range in locations with imported breeds). There were significant associations of temperature-related parameters with the annual frequency of cases of neonatal hypothermia seen at a veterinary teaching hospital, as well as with the average proportion of Haemonchus contortus larvae in faecal samples and the frequency of cases of H. contortus resistance reported by a veterinary parasitology laboratory.
Heritage and Sustainability: Regulating Participation
Authors: Rosetti Ilaria , Bertrand Cabral Clara , Pereira Roders Ana , Jacobs Marc , Albuquerque Rosana
Published: February 2022

In the past three decades, there has been increasing research carried out on the role of heritage and its processes in achieving broader sustainable development objectives beyond heritage conservation. As part of this movement, people-centered approaches and participation have been widely integrated into international regulations and guidelines on heritage management, stimulating the implementation of case studies-based research worldwide. Despite the wide advocacy of participatory heritage practices’ contributions to more inclusive and culturally sensitive local development in a great variety of projects, there is limited research into the roles these practices can have in addressing sustainability objectives. How are these roles addressed in international heritage regulatory frameworks, and what forms of participation are promoted for their fulfillment? This paper seeks to answer this research question through a content analysis of international declarations, conventions, guidelines, and policy documents focused on the roles and forms of participation that are promoted. A crossed-matched analysis of results reveals that active forms of participation are those most used to promote all roles and subcategories of participation, as a right, as a driver, and as an enabler of sustainable development. However, fewer active forms are presented as complementary at different stages of sustainability-oriented heritage practices. Moreover, a higher incidence of generic forms of participation can be observed in documents addressing international stakeholders, while partnership and intervention are to be found in those targeting regional and local actors. Nevertheless, the low incidence of decisional forms of participation confirms the challenges of power-sharing at all scales. Trends and influences are highlighted, informing heritage research, governance, and policymaking, but also revealing gaps and ambiguities in current regulations that further research encompassing a larger number of documents might confirm.