bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanocomposites of Graphene Oxide—Silver Nanoparticles for Enhanced Antibacterial Activity: Mechanism of Action and Medical Textiles Coating
Authors: Lange Agata , Sawosz Ewa , Wierzbicki Mateusz , Kutwin Marta , Daniluk Karolina , Strojny Barbara , Ostrowska Agnieszka , Wójcik Barbara , Łojkowski Maciej , Gołębiewski Marcin , Chwalibog André , Jaworski Sławomir
Published: April 2022

The resistance of microorganisms to antibiotics is a crucial problem for which the application of nanomaterials is among a growing number of solutions. The aim of the study was to create a nanocomposite (composed of graphene oxide and silver nanoparticles) with a precise mode of antibacterial action: what enables textiles to be coated in order to exhibit antibacterial properties. A characterization of nanomaterials (silver nanoparticles and graphene oxide) by size distribution, zeta potential measurements, TEM visualization and FT-IR was performed. The biological studies of the nanocomposite and its components included the toxicity effect toward two pathogenic bacteria species, namely Pseudomonas aeruginosa and Staphylococcus aureus, interaction of nanomaterials with the outer layer of microorganisms, and the generation of reactive oxygen species and lipid peroxidation. Afterwards, antibacterial studies of the nanocomposite’s coated textiles (cotton, interlining fabric, polypropylene and silk) as well as studies of the general toxicity towards a chicken embryo chorioallantoic membrane model were conducted. The toxicity of the nanocomposite used was higher than its components applied separately (zones of growth inhibition for P. aeruginosa for the final selected concentrations were as follows: silver nanoparticles 21 ± 0.7 mm, graphene oxide 14 ± 1.9 mm and nanocomposite 23 ± 1.6 mm; and for S. aureus were: silver nanoparticles 27 ± 3.8 mm, graphene oxide 14 ± 2.1 mm, and nanocomposite 28 ± 0.4 mm. The viability of P. aeruginosa and S. aureus after treatment with selected GO-Ag decreased to 27% and 31%, respectively, compared to AgNPs, when the viability of both species was 31% and 34%, accordingly). The coated textiles showed encouraging antibacterial features without general toxicity towards the chicken embryo chorioallantoic membrane model. We demonstrated that graphene oxide might constitute a functional platform for silver nanoparticles, improving the antibacterial properties of bare silver. Due to the application of the nanocomposite, the textiles showed promising antibacterial features with a low general toxicity, thereby creating a wide possibility for them to be used in practice.
Removal of Fe2+ and Mn2+ from Polluted Groundwater by Insoluble Humic Acid/Tourmaline Composite Particles
Authors: Liu Ling , Zhang Tianyi , Yu Xiaowan , Mkandawire Vitumbiko , Ma Jiadi , Li Xilin
Published: April 2022

Insoluble humic acid/tourmaline composite particles (IHA/TM) were prepared by combining inorganic tourmaline (TM) with the natural organic polymer humic acid (HA) and carbonizing them at 330 °C to study the removal characteristics and mechanism of Fe2+ and Mn2+. The results showed that the optimal ratio of TM to IHA is 2:3. When the temperature of the IHA/TM composite particles was 35 °C and the pH was 6, the adsorption of Fe2+ and Mn2+ by IHA/TM reached equilibrium at 240 min. The optimum dose of the adsorbent was 10 g/L, and the equilibrium adsorption capacities of Fe2+ and Mn2+ were 5.645 mg/g and 3.574 mg/g, respectively. The process of IHA/TM adsorption of Fe2+ and Mn2+ in water was spontaneous, endothermic and sustainable, and cooling was not conducive to adsorption. The pseudo-second order kinetic equation can well reflect the adsorption mechanism of IHA/TM on Fe2+ and Mn2+, and the Langmuir adsorption model better describes the isothermal adsorption behaviour. The material characterisation and adsorption experiments indicate that surface coordination and chemical precipitation are the main mechanisms of Fe2+ and Mn2+ removal by IHA/TM.
Degradation Behavior and Mechanical Integrity of a Mg-0.7Zn-0.6Ca (wt.%) Alloy: Effect of Grain Sizes and Crystallographic Texture
Authors: Millán-Ramos Benjamin , Morquecho-Marín Daniela , Silva-Bermudez Phaedra , Ramírez-Ortega David , Depablos-Rivera Osmary , García-López Julieta , Fernández-Lizárraga Mariana , Almaguer-Flores Argelia , Victoria-Hernández José , Letzig Dietmar , Rodil Sandra E.
Published: April 2022

The microstructural characteristics of biodegradable Mg alloys determine their performance and appropriateness for orthopedic fixation applications. In this work, the effect of the annealing treatment of a Mg-0.7Zn-0.6Ca (ZX11) alloy on the mechanical integrity, corrosive behavior, and biocompatibility-osteoinduction was studied considering two annealing temperatures, 350 and 450 °C. The microstructure showed a recrystallized structure, with a lower number of precipitates, grain size, and stronger basal texture for the ZX11-350 condition than the ZX11-450. The characteristics mentioned above induce a higher long-term degradation rate for the ZX11-450 than the ZX11-350 on days 7th and 15th of immersion. In consequence, the mechanical integrity changes within this period. The increased degradation rate of the ZX11-450 condition reduces 40% the elongation at failure, in contrast with the 16% reduction for the ZX11-350 condition. After that period, the mechanical integrity remained unchanged. No cytotoxic effects were observed for both treatments and significant differentiation of mesenchymal stem cells into the osteoblast phenotype was observed.
Monolayer SnI2: An Excellent p-Type Thermoelectric Material with Ultralow Lattice Thermal Conductivity
Authors: Xie Qing-Yu , Liu Peng-Fei , Ma Jiang-Jiang , Kuang Fang-Guang , Zhang Kai-Wang , Wang Bao-Tian
Published: April 2022

Using density functional theory and semiclassical Boltzmann transport equation, the lattice thermal conductivity and electronic transport performance of monolayer SnI2 were systematically investigated. The results show that its room temperature lattice thermal conductivities along the zigzag and armchair directions are as low as 0.33 and 0.19 W/mK, respectively. This is attributed to the strong anharmonicity, softened acoustic modes, and weak bonding interactions. Such values of the lattice thermal conductivity are lower than those of other famous two-dimensional thermoelectric materials such as MoO3, SnSe, and KAgSe. The two quasi-degenerate band valleys for the valence band maximum make it a p-type thermoelectric material. Due to its ultralow lattice thermal conductivities, coupled with an ultrahigh Seebeck coefficient, monolayer SnI2 possesses an ultrahigh figure of merits at 800 K, approaching 4.01 and 3.34 along the armchair and zigzag directions, respectively. The results indicate that monolayer SnI2 is a promising low-dimensional thermoelectric system, and would stimulate further theoretical and experimental investigations of metal halides as thermoelectric materials.
Multi-Step Enzymatic Production and Purification of 2-Keto-3-Deoxy-Galactonate from Red-Macroalgae-Derived Agarose
Authors: Yu Sora , Park So Young , Kim Dong Hyun , Yun Eun Ju , Kim Kyoung Heon
Published: April 2022

2-keto-3-deoxy sugar acids, which have potential as precursors in medicinal compound production, have gained attention in various fields. Among these acids, 2-keto-3-deoxy-l-galactonate (KDGal) has been biologically produced from D-galacturonate originating from plant-derived pectin. KDGal is also found in the catabolic pathway of 3,6-anhydro-l-galactose (AHG), the main component of red-algae-derived agarose. AHG is converted to 3,6-anhydrogalactonate by AHG dehydrogenase and subsequently isomerized to KDGal by 3,6-anhydrogalactonate cycloisomerase. Therefore, we used the above-described pathway to produce KDGal from agarose. Agarose was depolymerized to AHG and to agarotriose (AgaDP3) and agaropentaose (AgaDP5), both of which have significantly higher molecular weights than AHG. When only AHG was converted to KDGal, AgaDP3 and AgaDP5 remained unreacted. Finally, KDGal was effectively purified from the enzymatic products by size-exclusion chromatography based on the differences in molecular weights. These results show that KDGal can be enzymatically produced and purified from agarose for use as a precursor to high-value products.
Automatic Walking Method of Construction Machinery Based on Binocular Camera Environment Perception
Authors: Fang Zhen , Lin Tianliang , Li Zhongshen , Yao Yu , Zhang Chunhui , Ma Ronghua , Chen Qihuai , Fu Shengjie , Ren Haoling
Published: April 2022

In this paper, we propose an end-to-end automatic walking system for construction machinery, which uses binocular cameras to capture images of construction machinery for environmental perception, detects target information in binocular images, estimates the relative distance between the current target and cameras, and predicts the real-time control signal of construction machinery. This system consists of two parts: the binocular recognition ranging model and the control model. Objects within 5 m can be quickly detected by the recognition ranging model, and at the same time, the distance of the object can be accurately ranged to ensure the full perception of the surrounding environment of the construction machinery. The distance information of the object, the feature information of the binocular image, and the control signal of the previous stage are sent to the control model; then, the prediction of the control signal of the construction machinery can be output in the next stage. In this way, the automatic walking experiment of the construction machinery in a specific scenario is completed, which proves that the model can control the machinery to complete the walking task smoothly and safely.
The Effect of a Multidisciplinary Lifestyle Intervention on Health Parameters in Children versus Adolescents with Severe Obesity
Authors: van de Pas Kelly G. H. , Lubrecht Judith W. , Hesselink Marijn L. , Winkens Bjorn , van Dielen François M. H. , Vreugdenhil Anita C. E.
Published: April 2022

Lifestyle interventions are the common treatment for children and adolescents with severe obesity. The efficacy of these interventions across age groups remain unknown. Therefore, this study aimed to compare the effectiveness of a lifestyle intervention on health parameters between children and adolescents with severe obesity. A longitudinal design was carried out at the Centre for Overweight Adolescent and Children’s Healthcare (COACH) between December 2010 and June 2020. Children (2–11 years old, n = 83) and adolescents (12–18 years old, n = 77) with severe obesity received a long-term, tailored, multidisciplinary lifestyle intervention. After 1 year, 24 children (28.9%) and 33 adolescents (42.9%) dropped out of the intervention. The primary outcome was the change in body mass index (BMI) z-score after one and two years of intervention. The decrease in BMI z-score over time was significantly higher in children compared to adolescents, the mean decrease was 0.15 (0.08–0.23) versus 0.03 (−0.05–0.11) after one year and 0.25 (0.15–0.35) versus 0.06 (−0.06–0.17) after two years of intervention; p values for the difference between children and adolescents were 0.035 and 0.012. After two years, multiple improvements in cardio metabolic health parameters were observed, especially in children. In conclusion, during our tailored lifestyle intervention, a positive and maintained effect on health parameters was observed in children with severe obesity. Compared to children, the effect on health parameters was less pronounced in adolescents.
Hempseed (Cannabis sativa) Peptide H3 (IGFLIIWV) Exerts Cholesterol-Lowering Effects in Human Hepatic Cell Line
Authors: Li Jianqiang , Bollati Carlotta , Bartolomei Martina , Mazzolari Angelica , Arnoldi Anna , Vistoli Giulio , Lammi Carmen
Published: April 2022

Hempseed (Cannabis sativa) protein is an important source of bioactive peptides. H3 (IGFLIIWV), a transepithelial transported intestinal peptide obtained from the hydrolysis of hempseed protein with pepsin, carries out antioxidant and anti-inflammatory activities in HepG2 cells. In this study, the main aim was to assess its hypocholesterolemic effects at a cellular level and the mechanisms behind this health-promoting activity. The results showed that peptide H3 inhibited the 3-hydroxy-3-methylglutaryl co-enzyme A reductase (HMGCoAR) activity in vitro in a dose-dependent manner with an IC50 value of 59 μM. Furthermore, the activation of the sterol regulatory element binding proteins (SREBP)-2 transcription factor, followed by the increase of low-density lipoprotein (LDL) receptor (LDLR) protein levels, was observed in human hepatic HepG2 cells treated with peptide H3 at 25 µM. Meanwhile, peptide H3 regulated the intracellular HMGCoAR activity through the increase of its phosphorylation by the activation of AMP-activated protein kinase (AMPK)-pathways. Consequently, the augmentation of the LDLR localized on the cellular membranes led to the improved ability of HepG2 cells to uptake extracellular LDL with a positive effect on cholesterol levels. Unlike the complete hempseed hydrolysate (HP), peptide H3 can reduce the proprotein convertase subtilisin/kexin 9 (PCSK9) protein levels and its secretion in the extracellular environment via the decrease of hepatic nuclear factor 1-α (HNF1-α). Considering all these evidences, H3 may represent a new bioactive peptide to be used for the development of dietary supplements and/or peptidomimetics for cardiovascular disease (CVD) prevention.
First Molecular Confirmation of Treponema spp. in Lesions Consistent with Digital Dermatitis in Chilean Dairy Cattle
Authors: Canales Nivia , Bustamante Hedie , Wilson-Welder Jennifer , Thomas Cristian , Ramirez Emilio , Salgado Miguel
Published: April 2022

Digital dermatitis (DD) is a highly contagious and infectious disease in cattle which has a considerable negative economic impact worldwide, and adversely affects animal welfare. Members of the genus Treponema are the only bacterial agents for which there is consistent evidence of participation in DD lesions. In Chile, DD has been described since the 1990s, but only under a clinical approach. To date, the presence of the pathogenic agent has not been confirmed in Chile by any type of confirmatory microbiological diagnosis. The aim of the present study was to detect the presence of Treponema spp. DNA in lesions consistent with DD, in Chilean dairy cattle for the first time. We provide PCR confirmation of Treponema spp. in Chilean dairy cattle affected by DD. The high rate of positive results, as well as the proportion of the main Treponema species involved, is in line with what have been described in published studies elsewhere. Future herd control plans should benefit from the molecular detection of these pathogenic bacteria associated with DD.
Disentangling a Thorny Issue: Myocarditis and Pericarditis Post COVID-19 and Following mRNA COVID-19 Vaccines
Authors: Rafaniello Concetta , Gaio Mario , Zinzi Alessia , Sullo Maria Giuseppa , Liguori Valerio , Ferraro Marialuisa , Petronzelli Fiorella , Felicetti Patrizia , Marchione Pasquale , Marra Anna Rosa , Rossi Francesco , De Angelis Antonella , Capuano Annalisa
Published: April 2022

Considering the clinical significance for myocarditis and pericarditis after immunization with mRNA COVID-19 vaccines, the present pharmacovigilance study aimed to describe these events reported with mRNA COVID-19 vaccines in the Vaccine Adverse Events Reporting System (VAERS). From 1990 to July 2021, the mRNA vaccines were the most common suspected vaccines related to suspected cases of myocarditis and/or pericarditis (myocarditis: N = 1,165; 64.0%; pericarditis: N = 743; 55.1%), followed by smallpox vaccines (myocarditis: N = 222; 12.2%; pericarditis: N = 200; 14.8%). We assessed all suspected cases through the case definition and classification of the Brighton Collaboration Group, and only definitive, probable, and possible cases were included in the analysis. Our findings suggested that myocarditis and pericarditis mostly involve young male, especially after the second dose with a brief time to onset. Nevertheless, this risk is lower (0.38/100,000 vaccinated people; 95% CI 0.36–0.40) than the risk of developing myocarditis after SARS-CoV-2 infection (1000–4000 per 100,000 people) and the risk of developing “common” viral myocarditis (1–10 per 100,000 people/year). Comparing with the smallpox vaccine, for which is already well known the association with myocarditis and pericarditis, our analysis showed a lower probability of reporting myocarditis (ROR 0.12, 95% CI 0.10–0.14) and pericarditis (ROR 0.06, 95% CI 0.05–0.08) following immunization with mRNA COVID-19 vaccines.
Correction: Alfei, S.; Zuccari, G. Recommendations to Synthetize Old and New β-Lactamases Inhibitors: A Review to Encourage Further Production. Pharmaceuticals 2022, 15, 384
Authors: Alfei Silvana , Zuccari Guendalina
Published: April 2022

In the original publication [...]
Real-World Analysis of Nivolumab and Atezolizumab Efficacy in Previously Treated Patients with Advanced Non-Small Cell Lung Cancer
Authors: Alonso-García Miriam , Sánchez-Gastaldo Amparo , Muñoz-Fuentes Miguel A. , Molina-Pinelo Sonia , Boyero Laura , Benedetti Johana Cristina , Bernabé-Caro Reyes
Published: April 2022

Nivolumab (anti-PD-1 antibody) and atezolizumab (anti-PD-L1 antibody) have shown superior survival outcomes and improved adverse effects compared to standard chemotherapy in advanced non-small cell lung cancer (NSCLC) patients. However, the efficacy of both treatments has not been directly compared in clinical trials. This retrospective, single-centre study was performed from June 2015 to December 2020 and included a cohort of 158 previously treated patients with stage IV or recurrent NSCLC who received PD-1 (nivolumab) (n = 89) or PD-L1 (atezolizumab) (n = 69) inhibitors at the Virgen del Rocío Hospital in Seville. The objective response rate (ORR) was 22.5% in the nivolumab group and 14.5% in the atezolizumab group (p = 0.140). Multivariate analysis did not show significant differences between the two groups for PFS and OS (PFS hazard ratio (HR): 0.80, 95% confidence interval (CI): 0.55–1.17, p = 0.260; OS HR: 0.79, 95% CI: 0.52–1.21, p = 0.281). Adverse events of all grades occurred in 68 patients in the nivolumab group (76.4%) and in 34 patients in the atezolizumab group (49.3%) (p < 0.001). Atezolizumab and nivolumab did not show statistically significant differences in survival outcomes in patients with NSCLC, even when stratified by histological subtype (squamous versus nonsquamous). However, the safety analysis suggested a more favourable toxicity profile for atezolizumab.
Effect of Process Parameters on Laser Powder Bed Fusion of Al-Sn Miscibility Gap Alloy
Authors: Confalonieri Chiara , Casati Riccardo , Gariboldi Elisabetta
Published: April 2022

Al-Sn binary system is a miscibility gap alloy consisting of an Al-rich phase and a Sn-rich phase. This system is traditionally applied in bearings and more recently found application as form-stable phase change material (PCM) exploiting solid-liquid phase transition of Sn. A careful choice of production process is required to avoid macro-segregation of the two phases, which have different densities and melting temperatures. In the present study, the additive manufacturing process known as laser powder bed fusion (LPBF) was applied to an Al-Sn alloy with 20% volume of Sn, as a rapid solidification process. The effect of process parameters on microstructure and hardness was evaluated. Moreover, feasibility and stability with thermal cycles of a lattice structure of the same alloy were experimentally investigated. An Al-Sn lattice structure could be used as container for a lower melting organic PCM (e.g., a paraffin or a fatty acid), providing high thermal diffusivity thanks to the metallic network and a “safety system” reducing thermal diffusivity if the system temperature overcomes Sn melting temperature. Even if focused on Al-Sn to be applied in thermal management systems, the study offers a contribution in view of the optimization of manufacturing processes locally involving high solidification rates and reheat cycles in other miscibility gap alloys (e.g., Fe-Cu) with similar thermal or structural applications.
Focused Lunar Imaging Experiment Using the Back Projection Algorithm Based on Sanya Incoherent Scatter Radar
Authors: Li Mingyuan , Yue Xinan , Ding Feng , Ning Baiqi , Wang Junyi , Zhang Ning , Luo Junhao , Huang Lijia , Wang Yonghui , Wang Zhongqiu
Published: April 2022

Previous ground-based, radar lunar imaging experiments have usually employed the Range-Doppler (RD) algorithm. This algorithm performs in the frequency domain and has high computational efficiency. However, in the case of a long coherent integration time, the defocus phenomenon will appear, and the image will be smeared. This study proposes the use of the back projection (BP) algorithm to obtain focused lunar images to solve this problem. The BP algorithm is a time-domain algorithm which is frequently employed in synthetic aperture radar (SAR) imaging and can theoretically achieve the focused imaging of each pixel in an arbitrarily long coherent integration time. However, the largest drawback of this algorithm is its high computational complexity. Therefore, this study only applies this method to map local regions of the moon. We select Sanya incoherent scatter radar (SYISR) as the transmitting and receiving device and utilize the linear frequency modulation chirp pulse to transmit right-hand, circularly polarized electromagnetic waves and to receive left-hand, circularly polarized echoes. RD and BP algorithms are simultaneously adopted to image the Pythagoras crater region, and a contrastive analysis is performed. The results show that the BP algorithm can be well applied to a ground-based, radar lunar imaging experiment and that it has a better focusing performance, but the effect is not as obvious as expected. Thus, the processing method needs to be further improved. In addition, the computational efficiency of BP is very low, and certain fast algorithms need to be applied to improve it.
Improved Forest Canopy Closure Estimation Using Multispectral Satellite Imagery within Google Earth Engine
Authors: Xie Bo , Cao Chunxiang , Xu Min , Yang Xinwei , Duerler Robert Shea , Bashir Barjeece , Huang Zhibin , Wang Kaimin , Chen Yiyu , Guo Heyi
Published: April 2022

The large area estimation of forest canopy closure (FCC) using remotely sensed data is of high interest in monitoring forest changes and forest health, as well as in assessing forest ecological services. The accurate estimation of FCC over the regional or global scale is challenging due to the difficulty of sample acquisition and the slow processing efficiency of large amounts of remote sensing data. To address this issue, we developed a novel bounding envelope methodology based on vegetation indices (BEVIs) for determining vegetation and bare soil endmembers using the normalized differences vegetation index (NDVI), modified bare soil index (MBSI), and bare soil index (BSI) derived from Landsat 8 OLI and Sentinel-2 image within the Google Earth Engine (GEE) platform, then combined the NDVI with the dimidiate pixel model (DPM), one of the most commonly used spectral-based unmixing methods, to map the FCC distribution over an area of more than 90,000 km2. The key processing was the determination of the threshold parameter in BEVIs that characterizes the spectral boundary of vegetation and soil endmembers. The results demonstrated that when the threshold equals 0.1, the extraction accuracy of vegetation and bare soil endmembers is the highest with the threshold range given as (0, 0.3), and the estimated spatial distribution of FCC using both Landsat 8 and Sentinel-2 images were consistent, that is, the area with high canopy density was mainly distributed in the western mountainous region of Chifeng city. The verification was carried out using independent field plots. The proposed approach yielded reliable results when the Landsat 8 data were used (R2 = 0.6, RMSE = 0.13, and 1-rRMSE = 80%), and the accuracy was further improved using Sentinel-2 images with higher spatial resolution (R2 = 0.81, RMSE = 0.09, and 1-rRMSE = 86%). The findings demonstrate that the proposed method is portable among sensors with similar spectral wavebands, and can assist in mapping FCC at a regional scale while using multispectral satellite imagery.
Fitting Nonlinear Equations with the Levenberg–Marquardt Method on Google Earth Engine
Authors: Wang Shujian , Xu Ming , Zhang Xunhe , Wang Yuting
Published: April 2022

Google Earth Engine (GEE) has been widely used to process geospatial data in recent years. Although the current GEE platform includes functions for fitting linear regression models, it does not have the function to fit nonlinear models, limiting the GEE platform’s capacity and application. To circumvent this limitation, this work proposes a general adaptation of the Levenberg–Marquardt (LM) method for fitting nonlinear models to a parallel processing framework and its integration into GEE. We compared two commonly used nonlinear fitting methods, the LM and nonlinear least square (NLS) methods. We found that the LM method was superior to the NLS method when we compared the convergence speed, initial value stability, and the accuracy of fitted parameters; therefore, we then applied the LM method to develop a nonlinear fitting function for the GEE platform. We further tested this function by fitting a double-logistic equation with the global leaf area index (LAI), normalized difference vegetation index (NDVI), and enhanced vegetation index (EVI) data to the GEE platform. We concluded that the nonlinear fitting function we developed for the GEE platform was fast, stable, and accurate in fitting double-logistic models with remote sensing data. Given the generality of the LM algorithm, we believe that the nonlinear function can also be used to fit other types of nonlinear equations with other sorts of datasets on the GEE platform.
Optimization of Numerical Methods for Transforming UTM Plane Coordinates to Lambert Plane Coordinates
Authors: Wang Kuangxu , Ye Sijing , Gao Peichao , Yao Xiaochuang , Zhao Zuliang
Published: April 2022

The rapid transformation from UTM (Universal Transverse Mecator) projection to Lambert projection helps to realize timely merging, inversion, and analysis of high-frequency partitioned remote sensing images. In this study, the transformation error and the efficiency of the linear rule approximation method, the improved linear rule approximation method, the hyperbolic transformation method, and the conformal transformation method were compared in transforming the coordinates of sample points on WGS84 (The World Geodetic System 1984)-UTM zonal projections to WGS84-Lambert projection coordinates. The effect of the grid aspect ratio on the coordinate transformation error of the conformal transformation method was examined. In addition, the conformal transformation method-based error spatial pattern of the sample points was analyzed. The results show that the conformal transformation method can better balance error and efficiency than other numerical methods. The error of the conformal transformation method is less affected by grid size. The maximum x-error is less than 0.36 m and the maximum y-error is less than 1.22 m when the grid size reaches 300 km × 300 km. The x- and y-error values decrease when square grids are used; namely, setting the grid aspect ratio close to 1 helps to weaken the effect of increasing grid area on the error. The dispersion of the error distribution and the maximum error of sample points both decrease relative to their minimum distance to the grid edge and stabilize at a minimum distance equal to 70 km. This study can support the rapid integration of massive remote sensing data over large areas.
Aerosols over East and South Asia: Type Identification, Optical Properties, and Implications for Radiative Forcing
Authors: Liu Yushan , Yi Bingqi
Published: April 2022

Identification of aerosol types has long been a difficult problem over East and South Asia due to various limitations. In this study, we use 2-dimensional (2-D) and multi-dimensional Mahalanobis distance (MD) clustering algorithms to identify aerosol characteristics based on the data from the Aerosol Robotic Network from March 1998 to February 2018 over the South and East Asian region (10°N~50°N, 70°E~135°E). The single scattering albedo (SSA), absorption Angstrom exponent (AAE), extinction Angstrom exponent (EAE), real index of refraction (RRI), and imaginary index of refraction (IRI) are utilized for classification of aerosols. Sub-regions with similar background conditions over East and South Asia are identified by hierarchical clustering algorithm to illustrate distinctive meteorological states in different areas. The East and South Asian aerosols are found to have distinct regional and seasonal features relating to the meteorological conditions, land cover, and industrial infrastructure. It is found that the proportions of dust aerosol are the highest in spring at the SACOL site and in summer at the sites near the Northern Indo-Gangetic Plain area. In spring, biomass-burning aerosols are dominant over the central Indo-China Peninsula area. The aerosol characteristics at coastal sites are also analyzed and compared with previous results. The 2-D clustering method is useful when limited aerosol parameters are available, but the results are highly dependent on the sets of parameters used for identification. Comparatively, the MD method, which considers multiple aerosol parameters, could provide more comprehensive classification of aerosol types. It is estimated that only about 50% of the data samples that are identifiable by the MD method could be classified by the 2-D methods, and a lot of undetermined data samples could be mis-classified by the 2-D methods. The aerosol radiative forcing (ARF) and the aerosol radiative forcing efficiency (ARFE) of various aerosol types at the top and the bottom of the atmosphere (TOA and BOA) are determined based on the MD aerosol classification. The dust aerosols are found to have the largest ARF at the TOA (−36 W/m2), followed by the urban/industrial aerosols and biomass-burning aerosols. The ARFE of biomass-burning aerosols at the BOA (−165 W/m2/AOD550nm) is the strongest among those of the other aerosol types. The comparison of the results by MD and 2-D methods shows that the differences in ARF and ARFE are generally within 10%. Our results indicate the importance of aerosol type classification in accurately attributing the radiative contributions of different aerosol components.
Exploring Dynamic Street Vendors and Pedestrians through the Lens of Static Spatial Configuration in Yuncheng, China
Authors: Sun Ziwen , Scott Iain , Bell Simon , Yang Yufeng , Yang Zichu
Published: April 2022

Extensive studies have demonstrated the relationship between static street networks and dynamic pedestrian movement. Street vendors temporarily appear in a vibrant space, closely engaging with numerous pedestrians. Is street vending distribution related to street network configuration? And if so, in what ways? This study investigates the heterogeneous relationships between pedestrians, vendors and the urban and suburban places they inhabit in Yuncheng by contrasting two different types of pedestrian-driven maps. The vending distribution map was identified via semi-structured interviews with urban managers (n = 11) in 2017. The spatial network configuration was examined through space syntax segment angular analysis, containing Integration, Choice and Combined Centrality properties at macro-, meso- and micro-scales. By overlapping the distribution map to the syntactic maps in the Quantum Geographic Information System (QGIS) platform, our results show that street vending distribution is most related to the Choice property at the meso-scale. Using semi-structured interviews (n = 53) and observations at two specific sites, we further found relationships tend to be opposed in urban and suburban areas. The study provides an alternative approach to integrating quantitative and qualitative data, expanding the theoretical and empirical understanding of spatial configuration and urban street activities related to walking and vending. This understanding has the potential to contribute to the design of more liveable street spaces.
Temperature Compensation of Fiber Bragg Grating Sensors in Smart Strand
Authors: Jeon Se-Jin , Park Sung Yong , Kim Sung Tae
Published: April 2022

Compared to other types of sensors, fiber optic sensors have improved accuracy and durability. Recently, the Smart Strand was developed to maximize the advantages of fiber optic sensors for measuring the cable forces in prestressed concrete structures or cable-supported bridges. The Smart Strand has fiber Bragg gratings (FBGs) embedded in a core wire of the seven-wire strand. Similar to other sensors, the strain measured at an FBG is affected by temperature; therefore, the temperature effect that is not related to the mechanical strain should be compensated for or corrected in the long-term measurement subjected to temperature variation. However, a temperature compensation procedure for the FBG has yet to be established, and relevant studies have used different formulas for the compensation. Moreover, when the FBG sensors are packaged with a certain material—such as fiber reinforced polymer—for protection, it is important to consider the interaction between the FBG, packaging material, and host material during thermal behavior. Therefore, this study proposed a reasonable procedure for temperature compensation for the FBG sensors embedded in packaging material and host material. In particular, the thermal sensitivity of the Smart Strand was intensively investigated. The proposed theoretical formulas were validated through comparison with data obtained from various specimens in a temperature-controlled chamber. Finally, the procedure was applied to correct the data measured using the Smart Strands in a 20-m-long full-scale specimen for about a year, thus resulting in a realistic trend of the long-term prestressing force.
Real-Time Map Matching with a Backtracking Particle Filter Using Geospatial Analysis
Authors: Harder Dorian , Shoushtari Hossein , Sternberg Harald
Published: April 2022

Inertial odometry is a typical localization method that is widely and easily accessible in many devices. Pedestrian positioning can benefit from this approach based on inertial measurement unit (IMU) values embedded in smartphones. Fitting the inertial odometry outputs, namely step length and step heading of a human for instance, with spatial information is an ubiquitous way to correct for the cumulative noises. This so-called map-matching process can be achieved in several ways. In this paper, a novel real-time map-matching approach was developed, using a backtracking particle filter that benefits from the implemented geospatial analysis, which reduces the complexity of spatial queries and provides flexibility in the use of different kinds of spatial constraints. The goal was to generalize the algorithm to permit the use of any kind of odometry data calculated by different sensors and approaches as the input. Further research, development, and comparisons have been done by the easy implementation of different spatial constraints and use cases due to the modular structure. Additionally, a simple map-based optimization using transition areas between floors has been developed. The developed algorithm could achieve accuracies of up to 3 m at approximately the 90th percentile for two different experiments in a complex building structure.
Posture Estimation Using Surface Electromyography during Wheelchair Hand-Rim Operations
Authors: Ohashi Satoshi , Shionoya Akira , Harada Keiu , Nagamori Masahito , Uchiyama Hisashi
Published: April 2022

This study examined competitive wheelchairs that facilitate sports participation. They can be moved straight ahead using only one arm. Our designed and developed competitive wheel-chairs have a dual hand-rim system. Their two hand-rims, attached to a drive wheel on one side, can be operated simultaneously for straight-ahead movement. Specifically, based on integrated electromyography (iEMG) data calculated from surface electromyography (sEMG), we examined the wheelchair loading characteristics, posture estimation, and effects on body posture during one-arm propulsion movement. The first experiment yielded insights into arm and shoulder-joint muscle activation from iEMG results obtained for two-hand propulsion and dual hand-rim system propulsion. Results suggest that muscle activation of one arm can produce equal propulsive force to that produced by two arms. The second experiment estimated the movement posture from iEMG during one-arm wheelchair propulsion. The external oblique abdominis is particularly important for one-arm wheelchair propulsion. The iEMG posture estimation validity was verified based on changes in the user body axis and seat pressure distribution. In conclusion, as confirmed by iEMG, which is useful to estimate posture during movement, one-arm wheelchair use requires different muscle activation sites and posture than when using two arms.
Analysis of the Objective Internal Load in Portuguese Skydivers in the First Jump of the Day
Authors: Machado Tiago , Serrano João , Pino-Ortega Jose , Silveira Paulo , Antúnez Antonio , Ibáñez Sergio José
Published: April 2022

The general objective of this study was to identify the variation in heart rate (HR) of Portuguese skydivers during 6 moments in their first jump of the day, bearing in mind the variable level of experience. Thirty-one Portuguese skydivers, 28 men and 3 women, aged between 19 and 62, participated in the study, 12 had A and B licenses (less experienced) and 19 had C and D licences (more experienced). The instrument used to record the heart rate of the skydivers at the different moments of their first jump of the day was the WIMU PRO. A repeated measures analysis of variance was used to analyse HR at different moments in the jump and its relation with the variables level of experience. Bonferroni multiple comparisons were performed to study the importance of the differences observed in HR at the different moments. The effect size was evaluated with partial eta squared. The results showed that average HR in this group of skydivers was 130 bpm, in the different moments of the jump. HR increases from the value recorded at rest until the moment of jumping from the plane and opening the parachute, reaching the highest average at that moment, then decreasing until contact with the ground. Comparing the variable, we found that the less experienced had higher HR than the more experienced at all moments during the jump. Statistically significant differences were found at the different moments of the jump, regarding HR (Max: p < 0.001, ƞ2p = 0.820; Min: p < 0.001, ƞ2p = 0.821; AVG: p < 0.001, ƞ2p = 0.834) Level of experience with jumping moment interaction, we only verified differences related to HR Min (p = 0.007, ƞ2p = 0.056),. With regard to experience, the identified differences were not statistically significant. Skydiving triggers an acute adaptive cardiovascular response which is reflected in the increase in the HR, between the moment of boarding the plane and the moment at which the parachute opens, thereafter decreasing until contact with the ground. The most experienced parachutists recorded the highest HR at the moment of landing and the least experienced at the moment of free fall.
Environmental and Economic Analysis of Heating Solutions for Rural Residences in China
Authors: Zhang Zhenying , Wang Jiaqi , Yang Meiyuan , Gong Kai , Yang Mei
Published: April 2022

A spatial assessment is important to explore appropriate heating schemes for rural residences in China. Taking rural residences in six typical cities of China as the focus, four heating solutions, namely, coal-fired boiler heating systems (CBHS), wall-hung gas-fired boiler heating systems (GBHS), direct electric heating systems (DEHS), and air source heat pump systems (ASHPS), are compared and analyzed from the perspectives of primary energy consumption, environmental impact and heating costs. The results show that the primary energy consumption and the environmental impact can be significantly reduced by using solutions of GBHS and ASHPS in comparison with CBHS. DEHS has the most significant primary energy consumption and environmental impact and is less economical. The weighted environmental impact of GBHS is reduced by over 94% compared with that of CBHS, the weighted environmental impact of ASHPS is reduced by 8–23%, 35–39%, and 43–44% compared with that of CBHS for severe cold regions, cold regions, and hot-summer and cold-winter regions, respectively. The life cycle cost of GBHS is about 33% higher than that of CBHS for the six typical cities. The life cycle cost of ASHPS is about 33–57% higher than CBHS for severe cold regions, but not much difference or even less than CBHS for cold regions and hot-summer and cold-winter regions.
Farmers’ Perception of the Use and Benefits of Cowpea Storage Methods in Northern Ghana
Authors: Osei-Asibey Ryan Kusi , Wireko-Manu Faustina Dufie , Aidoo Robert , Boakye-Achampong Stanley , Mills-Robertson Felix Charles , Baributsa Dieudonne
Published: April 2022

Insect infestation during the storage of cowpea is a major challenge among smallholder farmers in sub-Saharan Africa (SSA). Farmers use various postharvest storage methods to deal with insect pests, including insecticides, which may result in health and environmental hazards. Four hundred (400) cowpea farmers were interviewed on their perceptions and preference of different storage methods in Northern Ghana. About 58% of farmers applied insecticides, 50% used ash, and 42% used hermetic triple-layer bags (Purdue Improved Crop Storage, PICS) to store cowpea. Most farmers (85.6%) preferred the PICS technology for its effectiveness (compared to insecticides, ash, and botanicals). Reasons for the non-use of PICS bags included unavailability (39.5%) and high price (11.7%). Farmers perceived that storing cowpea in PICS bags lowered pesticide-related health risks for both farmers and consumers. Thus, there is a need to improve the availability and affordability of PICS bags in Northern Ghana.
Successive Cyclones Attacked the World’s Largest Mangrove Forest Located in the Bay of Bengal under Pandemic
Authors: Sharma Sahadev , Suwa Rempei , Ray Raghab , Mandal Mohammad
Published: April 2022

Despite the global focus on the COVID-19 pandemic, the promise of impact to tropical coastlines and stochasticity of destruction caused by tropical cyclones remains unaltered, forcing human societies to adapt to new unadaptable scenarios. Super Cyclone Amphan’s landfall—the third cyclone of the season within the world’s largest mangrove forest—brought a new uncertainty to this undeveloped region of South Asia. How do vulnerable people deal with multiple disasters that limit necessary humanitarian response while still maintaining the natural environmental integrity of a system harboring critical wildlife populations and protecting people from further disaster? We explored this reality for the Sundarbans region using a remote sensing technique and found that the western part of Sundarbans mangroves was severely damaged by Amphan, suggesting that rapid remote sensing techniques can help direct resources, and recognize the eventuality that response will be a best effort for now. If 2020 is a window, multiple disaster management scenarios may become more common in the future. Yet, society’s obligation for maintaining environmental integrity remains unchanged.
Developing a Framework to Integrate Circularity into Construction Projects
Authors: Többen Jeanine , Opdenakker Raymond
Published: April 2022

This study provides the first approach to integrating circularity in the early stages of a construction project by the project manager. The circular ambition of the Dutch government stimulates a different approach in project management compared to a traditionally applied approach in construction projects. Design science research (DSR) was used to develop a framework for project managers to integrate circularity in the initial phases of construction projects, and we divided this research into three steps: (1) investigate the problem, (2) design a solution and (3) validate the design. The performed design cycle and formulated design propositions resulted in a framework consisting of two A3 format pages. The framework explains a successful three-step approach: knowledge of circular economy in the construction sector is needed, circularity has to be integrated into the project preparation, and circularity has to be integrated into project management. Furthermore, the framework incorporates extra background information and a checklist with 27 identified success factors. The framework was validated by expert opinions as effective, is ready to be implemented and is described as useful for the current challenges, demands and questions of the market.
Decomposition and Decoupling Analysis of Carbon Emissions from Cultivated Land Use in China’s Main Agricultural Producing Areas
Authors: Fu Chun , Min Weiqi , Liu Hubei
Published: April 2022

In-depth analysis of the decoupling state between cultivated land carbon emissions and cultivated land use factors can provide a basis for coordinating the relationship between food security and ecological environment. On the base of systematically calculating the carbon source of cultivated land, this paper calculated the carbon emission of cultivated land in China’s main agricultural production areas from 2000 to 2020, and explored its temporal and spatial pattern and evolution process. Then, using the LMDI decomposition method and the improved kaya identity, the factors affecting the carbon emissions of cultivated land are divided into five effects: structure, economy, technology, society and population, and then the Tapio decoupling theory is used to analyze the relationship between carbon emissions and these five effects. At the same time, to explore the further relationship between carbon emissions and cultivated land structure, we also studied the decoupling state between carbon emissions and the cultivated land area of 6 main crops. The results showed: during the study period, carbon emissions experienced three stages: fluctuating growth, accelerated growth and slow decline. In the most recent stage, structural, economic and population effects still have some impact on the carbon emissions of cultivated land, changes in cultivated land area where cotton, sugar and tobacco are planted will still affect its carbon emissions. To intervene, policy measures such as promoting the use of clean energy, increasing agricultural imports, and increasing carbon taxes for some industries can be considered.
Composted Rabbit Manure as Organic Matrix for Manufacturing Horticultural Growing Media: Composting Process and Seedling Effects
Authors: Li Rangling , Hao Hongyun , Sun Hui , Wang Liangju , Wang Hongying
Published: April 2022

This study investigated composted rabbit manure as an organic matrix to replace peat for manufacturing horticultural growing media, where three kinds of rabbit manures were composted with temperatures > 50 °C lasting > 7 days, with a germination index > 70%. The heavy metal contents in rabbit manure were far lower than the thresholds in Chinese standards for safe use as horticultural growing media. Then, different ratios of compost and peat were mixed with perlite and vermiculite to manufacture growing media, which were evaluated in a 28-day seedling experiment with cabbage. The manufactured growing media characteristics could satisfy the seedlings’ requirements; air spaces in particular were improved from 15.7% to up to 28.7% by mixing composted manure. Seedling emergence percentages > 90% and good seedling qualities (including enhanced root length, seedling height, and chlorophyll content) indicated that composted rabbit manure could effectively replace peat to manufacture horticultural growing media. The best seedling performance was obtained with the following ratio of composted manure, peat, perlite, and vermiculite: 3:3:2:2. However, the mixing ratio could be further optimized, and other methods to reduce the salinity may be required for the different requirements of specific crops in further research.