bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparations from Various Organs of Sea Buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) as Important Regulators of Hemostasis and Their Role in the Treatment and Prevention of Cardiovascular Diseases
Authors: Olas Beata , Skalski Bartosz
Published: February 2022

Numerous studies on the chemical composition of various organs of sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) have found the plant to be a rich source of vitamins, phenolic compounds, amino acids, fatty acids, and micro- and macro-elements. Furthermore, other studies on preparations from various organs have found them to have significant anti-cancer, anti-ulcer, and hepatoprotective properties, as well as various antibacterial and antiviral activities. This paper reviews the current literature concerning the effect of different sea buckthorn preparations, i.e., extracts and fractions with various chemical contents, on hemostasis, and their positive role in the treatment and prevention of cardiovascular diseases. It also sheds new light on the mechanisms involved in their action on hemostasis both in vivo and in vitro. For these studies, biological materials, including blood platelets, plasma, and blood, were isolated from healthy subjects and those with cardiovascular risk factors. In addition, it describes the cardioprotective potential of commercial products from different organs of sea buckthorn.
An Evaluation of Probability of Adequate Nutrient Intake (PANDiet) Scores as a Diet Quality Metric in Irish National Food Consumption Data
Authors: Kirwan Laura B. , Walton Janette , Flynn Albert , Nugent Anne P. , McNulty Breige A.
Published: February 2022

Identifying reliable metrics which measure the quality of a diet to promote nutrient adequacy and long-term health is an important step in the development of a sustainable food system. The Probability of Adequate Nutrient Intake (PANDiet) scoring system has been used as a measure of dietary quality in interdisciplinary research in recent years. The aim of the current study is to apply the PANDiet scoring system, and to assess the validity of the score as a metric of nutritional adequacy, within the Irish population. The Irish National Adult Nutrition Survey is a representative database with detailed data on nutrient intakes (18–90 years; n = 1051 valid-reporters; 2008–2010) and biofluid analytes (blood n = 786; urine n = 778). The PANDiet scoring system was expanded to include seven macronutrients, twelve micronutrients, nine minerals, and total energy using an established methodology. PANDiet scores were assessed against the Alternate Healthy Eating Index (AHEI) and Alternate Mediterranean Diet (aMED) food-based scores. The average score for the population (μ) was 63.69 ± 0.23 and ranged from 38.27 to 89.74. Higher PANDiet scores were significantly associated with males, higher educated participants, non-smokers, and low-energy-dense diets (p < 0.001). Females between the ages of 18 and 35 had a significantly lower nutrient adequacy score (μ 59.17). PANDiet scores were significantly correlated with serum folate, riboflavin status, serum vitamin D (p < 0.05) and with AHEI and aMED scores (Rs 0.45 and 0.43, p < 0.0001). The nutritional contribution of food groups varied between genders and low, moderate, and high nutritional adequacy groups. The PANDiet scoring system facilitated a detailed analysis of nutritional adequacy across sub-groups of the population, and is a comprehensive and valid diet quality metric in Irish databases.
The Comparative Effects of Different Types of Oral Vitamin Supplements on Arterial Stiffness: A Network Meta-Analysis
Authors: Saz-Lara Alicia , Cavero-Redondo Iván , Martínez-Vizcaíno Vicente , Martínez-Ortega Isabel Antonia , Notario-Pacheco Blanca , Pascual-Morena Carlos
Published: February 2022

Arterial stiffness, a significant prognostic factor of cardiovascular disease, may be affected by dietary factors. Research on the effects of oral vitamin supplements on arterial stiffness and/or endothelial function has produced controversial results. Therefore, the aim of this network meta-analysis was to comparatively assess the effect of different types of oral vitamin supplements on arterial stiffness in the adult population. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for randomized controlled trials from their inception to 30 September 2021. A network meta-analysis using a frequentist perspective was conducted to assess the effects of different types of oral vitamin supplements on arterial stiffness, as determined by pulse wave velocity. In total, 22 studies were included, with a total of 1318 participants in the intervention group and 1115 participants in the placebo group. The included studies were listed in an ad hoc table describing direct and indirect comparisons of the different types of vitamins. Our findings showed that, in both pairwise comparison and frequentist network meta-analysis, the different types of oral vitamin supplements did not show statistically significant effects on arterial stiffness. However, when oral vitamin supplementation was longer than 12 weeks, vitamin D3 showed a significant reduction in arterial stiffness, compared with the placebo (ES: −0.15; 95% CI: −0.30, −0.00; −60.0% m/s) and vitamin D2 (ES: −0.25; 95% CI: −0.48, −0.02, −52.0% m/s). In summary, our study confirms that oral vitamin D3 supplementation for more than 12 weeks could be an effective approach to reduce arterial stiffness and could be considered a useful approach to improve vascular health in patients at high risk of cardiovascular disease.
Evaluation of Dietary Quality Based on Intelligent Ordering System and Chinese Healthy Eating Index in College Students from a Medical School in Shanghai, China
Authors: Liu Shaojie , Wang Jiangqi , He Gengsheng , Chen Bo , Jia Yingnan
Published: February 2022

We intended to precisely evaluate the dietary quality of male and female medical college students using canteen data from the “Intelligent Ordering System” (IOS), combined with the supplemental food frequency questionnaire (SFFQ) and the Chinese Healthy Eating Index (CHEI) in Shanghai, China, to explore the potential factors influencing dietary quality. A total of 283 college students with the average age of 24.67 ± 3.21 years and Body Mass Index of 21.46 ± 3.49 kg/m2 in the medical school were enrolled in this study, and an online questionnaire investigation was conducted to collect the general information, lifestyle behavior, and SFFQ. The dietary data of the study participants from the school canteen were exported from the IOS of the Information Office of Fudan University. The CHEI consists of 17 components and the total score is 100, with a maximum score of each component of 5 or 10. We calculated each component score of the CHEI and aggregated the total score for male and female study participants. The Chi-square test and Wilcoxon rank sum test were employed in comparing the differences between the demographic characteristics and CHEI component scores of males and females. Univariate and multiple linear regression models were employed to examine the potential influencing factors of the total CHEI score. The CHEI median score was 66.65, and the component score for total grains was relatively low. Added sugars was the most overconsumed CHEI component. There were relatively serious deficiencies, based on the CHEI component scores, in fruits, soybeans, fish and seafood, and seeds and nuts in both sexes. Females had significantly higher CHEI scores than males (68.38 versus 64.31). The scores for tubers, total vegetables, dark vegetables, fruits, fish and seafood, dairy, and red meats were significantly higher in females than in males. Influencing factors including sex, education, dietary health literacy, and amount of time spent sedentarily were significantly associated with CHEI score. Our research revealed that the overall dietary quality needs to be further improved for college students at the medical school in Shanghai, China, with low intakes of total grains, fruits, soybeans, fish and seafood, and seeds and nuts, and high intakes of added sugars. Compared with males, females showed higher diet quality and conformed more strongly with the recommended Dietary Guideline for Chinese. Education, dietary health literacy, and amount of time spent sedentarily should be noted for improving the dietary quality of college students.
Akt/mTOR Activation in Lung Cancer Tumorigenic Regulators and Their Potential Value as Biomarkers
Authors: Sousa Carolina , Silva-Lima Beatriz , Videira Mafalda
Published: February 2022

The high incidence and modest therapeutic outcomes of lung cancer have prompted the identification of cell molecular targets/biomarkers within the complex networks of interactions involved in cell malignancy. Most of the EMT-related regulatory mediators underline patients’ biologic variations, therapeutic refractory events, and tumor cell heterogeneity. Patient stratification based on the understanding of the relevant pathways, such as the PI3K/Akt axis crucial in EMT initiation, could favorably alter disease management. Significant clinical advantage could be expected when overexpressed Akt tyrosine kinase (Akt2) is addressed as a malignant biomarker to guide clinical management decisions, improving prognosis in lung cancer patients. Moreover, one should not miss the opportunity of using it as a druggable target aiming at the inhibition of the downstream complexity that underlies cell proliferation and survival, expression of stemness markers and drug resistance. The value of mTOR, as a downstream target of Akt, and the further activation of EMT transcription factors Twist, Snail and Zeb1 are revisited in this review. An in-depth state-of-the-art assessment provides evidence of its role in the mechanistic inhibition of epithelial markers, such as E-cadherin and miR-200, while inducing the expression of the mesenchymal ones, such as vimentin, N-cadherin, and miR-21. Lastly, evidence suggesting another transcription factor, FOXM1, as the link between the PI3K/Akt and Wnt/β-catenin pathways, prompting cell metabolism through the regulation of p70S6K, is analyzed. A more realistic approach is advised to address unmet clinical needs and support decision making at a clinical level. Taking into consideration several complex intracellular interactions might further improve patient stratification and result in better outcomes.
Ointment-Based Combination of Dittrichia viscosa L. and Marrubium vulgare L. Accelerate Burn Wound Healing
Authors: Mssillou Ibrahim , Agour Abdelkrim , Slighoua Meryem , Chebaibi Mohamed , Amrati Fatima Ez-Zahra , Alshawwa Samar Zuhair , kamaly Omkulthom Al , El Moussaoui Abdelfattah , Lyoussi Badiaa , Derwich Elhoussine
Published: February 2022

Burns constitute a major challenge in medical science, and plants can be part of the solution. Dittrichia viscosa L. (Asteraceae) and Marrubium vulgare L. (Lamiaceae) are widely used in Moroccan traditional medicine to treat several diseases and possess high potency to cure wounds. This study aimed to investigate in vivo the analgesic, anti-inflammatory, and burn-healing effects of both plants and their mixture. The hydro-ethanolic extract of both plants was analyzed using high-performance liquid chromatography with diode-array detection (HPLC-DAD). Burns were conducted on dorsal part of rats, and the wound healing process was evaluated during 21 days. Gallic acid, caffeic acid, ferulic acid, and quercetin were identified in M. vulgare extract. The analysis recorded the presence of caffeic acid, rosmarinic acid, rutin, and quercetin in D. viscosa. The group treated with the mixture showed the lowest abdominal contractions (30.4 ± 7.52) with the highest percentage of inhibition (69.12 ± 7.04%). The inhibition of paw inflammation for M. vulgare was 47.65%, followed by D. viscosa (33.86%) and the mixture (30.41%). The mixture showed the highest wound contraction at day 7 (33.16 ± 14.33%) and day 14 (87.54 ± 3.98%). D. viscosa showed the highest wound contraction on the 21st day (99.28 ± 0.44%). In conclusion, both plants and their combination showed promising results for burn healing.
Nonviral Delivery Systems of mRNA Vaccines for Cancer Gene Therapy
Authors: Wang Yusi , Zhang Rui , Tang Lin , Yang Li
Published: February 2022

In recent years, the use of messenger RNA (mRNA) in the fields of gene therapy, immunotherapy, and stem cell biomedicine has received extensive attention. With the development of scientific technology, mRNA applications for tumor treatment have matured. Since the SARS-CoV-2 infection outbreak in 2019, the development of engineered mRNA and mRNA vaccines has accelerated rapidly. mRNA is easy to produce, scalable, modifiable, and not integrated into the host genome, showing tremendous potential for cancer gene therapy and immunotherapy when used in combination with traditional strategies. The core mechanism of mRNA therapy is vehicle-based delivery of in vitro transcribed mRNA (IVT mRNA), which is large, negatively charged, and easily degradable, into the cytoplasm and subsequent expression of the corresponding proteins. However, effectively delivering mRNA into cells and successfully activating the immune response are the keys to the clinical transformation of mRNA therapy. In this review, we focus on nonviral nanodelivery systems of mRNA vaccines used for cancer gene therapy and immunotherapy.
Liposomal Formulations Enhance the Anti-Inflammatory Effect of Eicosapentaenoic Acid in HL60 Cells
Authors: Kaur Puneet , Gao Jin , Wang Zhenjia
Published: February 2022

Dietary omega 3 polyunsaturated fatty acids (PUFAs), including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), have been reported to be beneficial for cardiovascular diseases and cancer. Such diseases share a common pathophysiological feature of inflammation responses, such as unbalanced oxidative stress and increased cytokine release. PUFAs show anti-inflammatory effects, and thus, they are potential therapeutics to treat inflammatory disorders. Here, we proposed a novel liposomal formulation of EPA (EPA-liposomes), and the liposome was PEGylated to increase their stability. In the study, we measured the physicochemical characteristics of EPA-liposomes and their anti-inflammatory effects in neutrophil-like cells (HL 60 cells). The results showed that EPA-liposomes dramatically decreased the production of NO, ROS, and cytokines compared to EPA alone, and the molecular mechanism is associated with biosynthesis of RvE1 from EPA, and RvE1 binds to GPCRs to mediate the anti-inflammatory effects.
Facile Solvent-Free Preparation of Antioxidant Idebenone-Loaded Nanoparticles for Efficient Wound Healing
Authors: Yang HeeSeon , Yu Sohyeon , Kim Jisu , Baek KumJu , Lee Young-Ran , Lee Hye Sun , Choi Won Il , Sung Daekyung
Published: February 2022

The excessive production of reactive oxygen species (ROS) causes harmful effects, including biomolecular damage and inflammation. ROS due to ultraviolet rays, blue light, and fine dust harm the skin, causing urban-related aging. Therefore, a strong antioxidant that relieves oxidative stress in the skin and removes ROS is required. Idebenone (IB) is a powerful antioxidant but is poorly soluble and thus has low solubility in water, resulting in low bioavailability. In this study, IB-loaded nanoparticles (IB@NPs) were synthesized by loading IB without an organic solvent into nanoparticles that can provide high loading efficiency and stability for solubilization. Indeed, the synthesized IB@NPs exhibited long-term stability through dynamic light scattering, methylene blue staining, and redispersion assays, and IB@NPs prepared with a 5 wt% IB loading content were found to be optimal. The antioxidant activity of IB@NPs evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was significantly higher than that of unloaded IB. In addition, IB@NPs showed excellent biocompatibility, inhibited oxidative damage to mouse NIH-3T3 fibroblasts, and reduced intracellular ROS generation according to an in vitro DPPH antioxidant assay. Most notably, IB@NPs significantly promoted wound healing in vitro, as demonstrated by scratch assays. Therefore, as carriers with excellent stability, IB@NPs have potential cosmetic and pharmaceutical applications.
Management of Periodontal Disease with Adjunctive Therapy with Ozone and Photobiomodulation (PBM): A Randomized Clinical Trial
Authors: Scribante Andrea , Gallo Simone , Pascadopoli Maurizio , Soleo Riccardo , Di Fonso Fabio , Politi Luca , Venugopal Adith , Marya Anand , Butera Andrea
Published: February 2022

Periodontitis is an inflammatory condition of the soft and hard tooth-supporting tissues, representing the first cause of tooth loss. In addition to standard mechanical debridement (Scaling and Root Planing, SRP), further approaches have been proposed as adjuncts. The aim of the present randomized clinical trial is to compare the efficacy of ozone or photobiomodulation (PBM) therapy in addition to SRP to treat periodontal disease. According to a split-mouth design, 240 pathological sites, corresponding to 30 periodontal patients, were randomly divided according to the professional oral hygiene protocol performed at baseline (T0) and after 1 (T1), 2 (T2), 3 (T3), 4 (T4), 5 (T5), and 6 (T6) months. A total of 120 sites underwent an ozonized water administration (ozone group), whereas the other 120 sites were treated with photobiomodulation (PBM group), both in addition to SRP. At every timepoint, the following clinical indexes were assessed: Probing Pocket Depth (PPD) (measured on six sites per element), Plaque Index (PI), and Bleeding on Probing (BOP). As regards PPD, significant intergroup differences were noticed from T5, with significantly lower values in the PBM group (p < 0.05), where values further decreased at T6 (p < 0.05). Both PI and BoP generally decreased from baseline to T6 in both groups; a significant difference was found between T0 and T1 among the groups (p < 0.05), with a progressively higher reduction in the PBM group among the time frames of the study, despite intergroup comparisons not being significant (p > 0.05). Both ozone and PBM appear to be effective adjuvant treatments to SRP, obtaining a slightly better outcome for the latter in the long term, with significant differences at T5 and T6 for PPD. However, because of the absence of standardized protocols for PBM considering both therapeutic and research purposes, no definitive conclusions can be reached, and further studies are required.
Scattering of Partially Coherent Vector Beams by a Deterministic Medium Having Parity-Time Symmetry
Authors: Zhang Xuan , Chen Yahong , Wang Fei , Cai Yangjian
Published: February 2022

We study the scattering properties of the partially coherent vector beams with the deterministic media having the classic symmetric and parity-time (PT) symmetric scattering potential functions. The closed-form expressions for the intensity and polarization matrix of the far-zone scattered field are obtained, under first-order Born approximation, when the partially coherent vector beams are taken to be radially polarized and the deterministic media are assumed as the four-point scatterers. We demonstrate both analytically and numerically that the far-zone scattered field becomes noncentrosymmetric and the directionality appears in the scattering pattern when the scattering potential function is switched from classic symmetry to PT symmetry. We show the effect of spatial coherence of the incident partially coherent vector beam on the directionality in scattering. We find that by turning the symmetry property of the spatial coherence function of the incident beam, i.e., into PT symmetry, the directionality in the far-zone scattering can be suppressed or enhanced, depending on the joint effect from the symmetry of the scattering potential and the symmetry of the spatial coherence. Our findings may be useful in the application of dynamic control of the directionality in light scattering.
Functional Hollow Ceramic Microsphere/Flexible Polyurethane Foam Composites with a Cell Structure: Mechanical Property and Sound Absorptivity
Authors: Lin Jia-Horng , Hsu Po-Yang , Huang Chen-Hung , Lai Mei-Feng , Shiu Bing-Chiuan , Lou Ching-Wen
Published: February 2022

Noise pollution is the primary environmental issue that is increasingly deteriorated with the progress of modern industry and transportation; hence, the purpose of this study is to create flexible PU foam with mechanical properties and sound absorption. In this study, hollow ceramic microsphere (HCM) is used as the filler of polyurethane (PU) foam for mechanical reinforcement. The sound absorption efficacy of PU pores and the hollow attribute of HCM contribute to a synergistic sound absorption effect. HCM-filled PU foam is evaluated in terms of surface characteristic, mechanical properties, and sound absorption as related to the HCM content, determining the optimal functional flexible PU foam. The test results indicate that the presence of HCM strengthens the stability of the cell structure significantly. In addition, the synergistic effect can be proven by a 2.24 times greater mechanical strength and better sound absorption. Specifically, with more HCM, the flexible PU foam exhibits significantly improved sound absorption in high frequencies, suggesting that this study successfully generates functional PU foam with high mechanical properties and high sound absorption.
Heavy Metal Ions Removal from Aqueous Solutions by Treated Ajwa Date Pits: Kinetic, Isotherm, and Thermodynamic Approach
Authors: Azam Mohammad , Wabaidur Saikh , Khan Mohammad , Al-Resayes Saud , Islam Mohammad
Published: February 2022

In the current study we prepared cost-effective adsorbents based on ajwa date pits to remove Cu(II) ions from aqueous medium. Adsorbents were studied using scanning electron microscopy (SEM), FT-IR, and Brunauer-Emmett-Teller (BET) methods to characterize the surface functionalities, morphology, pore size, and particle size. The concentration of Cu(II) ions in the studied samples was determined by atomic adsorption spectrometry technique (AAS). Adsorption method was performed sequentially in a batch system followed by optimization by studying the numerous conditions, for instance the initial amounts of Cu(II) ions, dosages of the adsorbent, contact time, and pH of the solution. The ideal pH observed for maximum adsorption capacity was ~6.5. Langmuir and Freundlich isotherm models correctly predicted the investigation results, with the maximum monolayer adsorption capacities for Cu(II) ions at 328 K being 1428.57 mg/g (treated ajwa date pits, TADP) and 1111.1 mg/g for as produced ajwa date pits (ADP). It was revealed that TADP possess greater adsorption capability than ADP. Recovery investigations revealed that the saturated adsorbents eluted the maximum metal with 0.1 M HCl. Cu(II) ions adsorption was observed to be reduced by 80–89% after the second regeneration cycle. For the raw and chemically processed ajwa date pits adsorbent, the Langmuir model performed significantly better than the Freundlich model. The results demonstrated that the adsorbent made from ajwa date pits could be an economical and environmentally friendly alternative for removing Cu(II) ion pollutant from aqueous media.
Product Development of Natural Fibre-Composites for Various Applications: Design for Sustainability
Authors: Asyraf Muhammad Rizal Muhammad , Syamsir Agusril , Zahari Nazirul Mubin , Supian Abu Bakar Mohd , Ishak Mohamad Ridzwan , Sapuan Salit Mohd , Sharma Shubham , Rashedi Ahmad , Razman Muhammad Rizal , Zakaria Sharifah Zarina Syed , Ilyas Rushdan Ahmad , Rashid Mohamad Zakir Abd
Published: February 2022

New product development review article aims to consolidate the principles and current literature on design for sustainability to seek the field’s future direction. In this point of view, the design for sustainability methods can be established under the idea of sustainability in dimensions of ecology, economy and social pillars. Design for sustainability concept is implemented in concurrent engineering, including concept, embodiment and detail design processes. Integrating sustainability in engineering designs is crucial to producing greener products, system innovation, and services aligned with current market demand. Currently, many concurrent engineering studies related to natural fibre-reinforced polymer composites associated with sustainability enhance the application of design for sustainability techniques by professional designers. However, the current literature is scarce in bridging the design for sustainability concept with concurrent engineering during the design development stage, and these areas should be further developed. Several other future research directions, such as the need for aligning with principles and applications, along with exploring the relationships between the design for sustainability techniques and views of sustainability, are presented in this review paper.
Bacterial Alginate-Based Hydrogel Reduces Hydro-Mechanical Soil-Related Problems in Agriculture Facing Climate Change
Authors: Barrientos-Sanhueza Cesar , Cargnino-Cisternas Danny , Díaz-Barrera Alvaro , Cuneo Italo F.
Published: February 2022

Agricultural systems are facing the negative impacts of erosion and water scarcity, directly impacting the hydro-mechanical behavior of soil aggregation. Several technologies have been proposed to reduce hydro-mechanical soil-related problems in agriculture. Biopolymer-based hydrogels have been reported to be a great tool to tackle these problems in soils. In this study, we investigated the hydro-mechanical behavior of different soils media treated with Ca-bacterial alginate hydrogel. We used an unconfined uniaxial compression test, aggregate stability test and hydraulic conductivity measurements to investigate the mechanical and hydraulic behavior of treated soils media. Our results from unconfined uniaxial compression test showed that yield stress (i.e., strength) increased in treated soils with higher kaolinite and water content (i.e., HCM3), compared with untreated coarse quartz sand (i.e., CM1). Furthermore, we found that temperature is an important factor in the gelation capacity of our hydrogel. At room temperature, HCM3 displayed the higher aggregate stability, almost 5.5-fold compared with treated coarse quartz sand (HCM1), while this differential response was not sustained at warm temperature. In general, the addition of different quantities of kaolinite decreased the saturated hydraulic conductivity for all treatments. Finally, bright field microscopy imaging represents the soil media matrix between sand and clay particles with Ca-bacterial alginate hydrogel that modify the hydro-mechanical behavior of different soils media. The results of this study could be helpful for the soil-related problems in agriculture facing the negative effects of climate change.
A Comparative Investigation on Structural and Chemical Differences between the Pith and Rind of Sunflower Stalk and Their Influences on Nanofibrillation Efficiency
Authors: Zhang Lingyan , Ren Wenting , Liu Fangqingxin , Xia Linmin , Wu Xiaomei , Yang Rilong , Yu Yan , Zhang Xuexia
Published: February 2022

The structure and chemical composition of cell walls play a vital role in the bioconversion and utilization of plants. In the present study, the cell wall structure and chemical composition of pith and rind from sunflower stalks were compared and correlated to their nanofibrillation efficiency with ultrasonic treatment. Mild chemical pretreatment using 1% or 4% NaOH without any bleaching process were applied prior to ultrasonication nanofibrillation. Significant structural and chemical differences were demonstrated between the pith and rind, with the former exhibiting a much lower lignin and hemicellulose contents, higher pectin, much looser cell structure and higher cell wall porosity than the latter. Alkaline treatment alone was sufficient to eliminate most of the hemicellulose and pectin from stalk pith, whereas only partial removal of hemicellulose and lignin was achieved for the woody rind part. After 30 min of ultrasonic treatment, the stalk pith exhibited fully defibrillated fibrils with a continuous and entangled micro/nanofibrillated network, whereas numerous micron-sized fiber and fragments remained for the rind. The results indicated that stalk pith is less recalcitrant and easier to be fibrillated with ultrasonication than rind, which must be correlated to their distinct differences in both structure and chemical composition.
Star-Branched Polyamides as the Matrix in Thermoplastic Composites
Authors: Núñez Carrero Karina C. , Herrero Manuel , Asensio María , Guerrero Julia , Merino Juan Carlos , Pastor José María
Published: February 2022

The aim of this study is the preparation of star-shaped branched polyamides (sPA6) with low melt viscosity, but also with improved mechanical properties by reactive extrusion. This configuration has been obtained by grafting a tri-functional, three-armed molecule: 5-aminoisophthalic-acid, used as a linking agent (LA). The balance between the fluidity, polarity and mechanical properties of sPA6s is the reason why these materials have been investigated for the impregnation of fabrics in the manufacture of thermoplastic composites. For these impregnation processes, the low viscosity of the melt has allowed the processing parameters (temperature, pressure and time) to be reduced, and its new microstructure has allowed the mechanical properties of virgin thermoplastic resins to be maintained. A significant improvement in the ultrasonic welding processes of the composites was also found when an energy director based on these materials was applied at the interface. In this work, an exhaustive microstructural characterization of the obtained sPAs is presented and related to the final properties of the composites obtained by film stacking.
SI ATRP for the Surface Modifications of Optically Transparent Paper Films Made by TEMPO-Oxidized Cellulose Nanofibers
Authors: Chen Jem-Kun , Huang Hsiang-Ya , Tu Cheng-Wei , Lee Li-Ting , Jamnongkan Tongsai , Huang Chih-Feng
Published: February 2022

Applications of cellulose nanofibers currently match the demands of biodegradable and renewable constituent biocomposites. In this study, we studied the process of preparing TEMPO-oxidized cellulose nanofibers (TOCNs). These nano-sized cellulose fibers (ca. 11 nm) can be fabricated to high transmittance and optically transparent paper (OP) films. Then the OP films can be facilely immobilized initiating sites for the subsequent surface-initiated atom transfer radical polymerization (SI ATRP). We investigated SI ATRP with styrene (St) kinetics and monitored chemical structure changes of the OP surfaces. The obtained OP-g-PSt significantly led to enhance thermal stability and alter the OP surface with hydrophobic compared to that of pristine OP film. Characterization was studied by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV–Vis spectroscopy, thermogravimetric analyzer (TGA), and water contact angle (WCA) measurements.
The Effect of Airfoil Camber on Pressure Fluctuation in Bidirectional Axial-Flow Pump
Authors: Meng Fan , Li Yanjun , Chen Jia , Xu Lei , Li Yalin
Published: February 2022

To obtain the influence of airfoil camber on the internal pressure fluctuation of a bidirectional axial-flow pump, the unsteady Reynolds time-averaged Navier–Stokes (URANS) equation was solved to predict the internal flow structure under three airfoil camber cases. The airfoil camber was quantitatively controlled by airfoil camber angle. The pressure standard deviation was used to define the local pressure fluctuation intensity (PFI) inside the impeller and guide vane. Fast Fourier transform was applied to analyze the frequency-domain characteristics of the pressure signal near the impeller–straight pipe interface and impeller–guide vanes interface. The results were validated by the external characteristic test. Under the forward condition, the area of high PFI near the outlet and leading edge of the impeller increased with a decrease in airfoil camber angle, and that near the leading edge of the guide vanes shifted to the middle section with a decrease in airfoil camber angle. The main frequency of the pressure signal near the impeller–guide vanes interface was the blade-passing frequency (BPF), and the main frequency amplitude increased with a decrease in airfoil camber angle. Under the reverse condition, the high PFI area near the inlet and the leading edge of the impeller declined with the decrease in airfoil camber angle. The main frequency of the pressure signal near the impeller–straight pipe interface and impeller–guide vanes interface was the BPF, and the main frequency amplitude decreased with a decrease in airfoil camber angle.
CFD-DEM Study of Bridging Mechanism of Particles in Ceramic Membrane Pores under Surface Filtration Conditions
Authors: Wang Hao , Wu Junfei , Fu Ping , Qu Zhiping , Zhao Wenjie , Song Yixuan
Published: February 2022

In the surface filtration process with pores larger than the particle size, the formation of particle bridges plays a crucial role in the filter cake structure and the filtration efficiency throughout the filtration process. First, to understand the microscopic information required for the bridging mechanism, we use the two-way coupling of computational fluid dynamics (CFD)–discrete element method (DEM) to simulate the deposition characteristics of particles in the pores of ceramic membranes. Next, by dynamically observing the deposition morphology and bridging process of particles, the bridging mechanism was revealed at the level of a single hole. Then, we studied the influence of particle concentration and inlet velocity on the bridge erection process. The results show that the bridging function of particles runs through the clean filtration stage and the transition stage. Particle concentration and inlet flow rate have a crucial influence on the formation of particle bridges and filtration efficiency.
CO Fluxes in Western Europe during 2017–2020 Winter Seasons Inverted by WRF-Chem/Data Assimilation Research Testbed with MOPITT Observations
Authors: Huang Yongjian , Wei Jianming , Jin Jiupin , Zhou Zhiwei , Gu Qianrong
Published: February 2022

The study of anthropogenic carbon monoxide (CO) emissions is crucial to investigate anthropogenic activities. Assuming the anthropogenic CO emissions accounted for the super majority of the winter CO fluxes in western Europe, they could be roughly estimated by the inversion approach. The CO fluxes and concentrations of four consecutive winter seasons (i.e., December–February) in western Europe since 2017 were estimated by a regional CO flux inversion system based on the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) and the Data Assimilation Research Testbed (DART). The CO retrievals from the Measurements Of Pollution In The Troposphere instrument (MOPITT) version 8 level 2 multi-spectral Thermal InfraRed (TIR)/Near-InfraRed (NIR) CO retrieval data products were assimilated by the inversion system. The analyses of the MOPITT data used by the inversion system indicated that the mean averaging kernel row sums of the surface level was about 0.25, and the difference percentage of the surface-level retrievals relative to a priori CO-mixing ratios was 14.79%, which was similar to that of the other levels. These results suggested the MOPITT’s surface-level observations contained roughly the same amount of information as the other levels. The inverted CO fluxes of the four winter seasons were 6198.15 kilotons, 4939.72 kilotons, 4697.80 kilotons, and 5456.19 kilotons, respectively. Based on the assumption, the United Nations Framework Convention on Climate Change (UNFCCC) inventories were used to evaluate the accuracy of the inverted CO fluxes. The evaluation results indicated that the differences between the inverted CO fluxes and UNFCCC inventories of the three winter seasons of 2017–2019 were 13.36%, −4.59%, and −4.76%, respectively. Detailed surface-CO concentrations and XCO comparative analyses between the experimental results and the external Community Atmosphere Model with Chemistry (CAM-Chem) results and the MOPITT data were conducted. The comparative analysis results indicated that the experimental results of the winter season of 2017 were obviously affected by high boundary conditions. The CO concentrations results of the experiments were also evaluated by the CO observation data from Integrated Carbon Observation System (ICOS), the average Mean Bias Error (MBE), and the Root Mean Square Error (RMSE) between the CO concentrations results of the inversion system, and the ICOS observations were −22.43 ppb and 57.59 ppb, respectively. The MBE and RMSE of the inversion system were 17.53-ppb and 4.17-ppb better than those of the simulation-only parallel experiments, respectively.
Data Processing of Gravity Base Network in Plateau Area: The Case of Qinghai Province, China
Authors: Wu Qiong , Liu Shi , Wang Bin , Zhong Linshan , Zhao Lijiang , Zhang Shengpeng , Li Hongqing
Published: February 2022

The latest gravity survey of the gravity base network in Qinghai Province, China, was conducted with six Scintrex CG gravimeters and this gravity survey was tied to existed gravity reference stations. In this gravity network with long segments and very rugged topography, the calibration of scale factors is a time-consuming progress and its accuracy may be affected by many uncertainties, and the change in drift rates of the relative gravimeters are complex over time in this long-term survey. The reasonable calculation of scale factors and drift rates plays an important role in improving the gravity estimation accuracy. In this paper, based on the least squares, robust least squares, and Bayesian methods, various parameter calculation methods were employed to process this gravity network. The performance and practicality of each method were analyzed in terms of internal and external accuracy. The results indicated that the scale factors calibrated in the baseline field had poor applicability due to insufficient gravity difference, in this case, the scale factors estimated by the adjustment models were more accurate, which weakened the correlation between gravity differences and mutual differences. The drift rates estimated by the Bayesian method were relatively smooth over time, while drift rates estimated using symmetric observations were more practical for the gravimeter with highly variable drift. The weight constraints of observations can be optimized by the robust least squares method, the gravity values obtained by it were more consistent with absolute gravity values than those obtained by the least squares method, and the robust least squares method was recommended to process gravity data in plateau areas.
Image Correction and In Situ Spectral Calibration for Low-Cost, Smartphone Hyperspectral Imaging
Authors: Davies Matthew , Stuart Mary B. , Hobbs Matthew J. , McGonigle Andrew J. S. , Willmott Jon R.
Published: February 2022

Developments in the portability of low-cost hyperspectral imaging instruments translate to significant benefits to agricultural industries and environmental monitoring applications. These advances can be further explicated by removing the need for complex post-processing and calibration. We propose a method for substantially increasing the utility of portable hyperspectral imaging. Vertical and horizontal spatial distortions introduced into images by ‘operator shake’ are corrected by an in-scene reference card with two spatial references. In situ light-source-independent spectral calibration is performed. This is achieved by a comparison of the ground-truth spectral reflectance of an in-scene red–green–blue target to the uncalibrated output of the hyperspectral data. Finally, bias introduced into the hyperspectral images due to the non-flat spectral output of the illumination is removed. This allows for low-skilled operation of a truly handheld, low-cost hyperspectral imager for agriculture, environmental monitoring, or other visible hyperspectral imaging applications.
A Study of Possible Correlations between Seismo-Ionospheric Anomalies of GNSS Total Electron Content and Earthquake Energy
Authors: Su Yung-Chih , Sha Jinming
Published: February 2022

In this study, we conduct a correlation analysis between the daily occurrence times of the increase and decrease anomalies in the global total electron content (TEC) in the ionosphere, and the daily earthquake energy release within 110–130°E longitude over the following three latitude regions: A: 13°S–0.5°S (22.3°S–10°S geomagnetic), B: 0.5°S–19.5°N (10°S–10°N geomagnetic), and C: 19.5°N–32.1°N (10°N–22.5°N geomagnetic). The TEC data from global ionosphere maps (GIMs) during earthquake events of M ≥ 2.5 that occurred in 2015–2018 are used in this study. The time series of daily seismic wave energy releases within the three regions and the daily occurrence times of the TEC anomalies in each GIM grid are computed. By time-shifting the time series, the correlations are calculated and compared globally, and the temporal characteristics are also examined. The disturbance storm time (Dst) index, planetary geomagnetic index Kp, and daily observed 10.7 cm solar flux (F10.7) are used to remove data associated with space weather variations. Although the seismo-ionospheric precursor is not confirmed by the statistical investigations, the greater occurrence times of TEC decrease anomalies are observed in the southeast in Region A, and the conjugate point 13 days prior to a M6.9 earthquake in Region A, which occurred on 5 August 2018, in accordance with the statistical results. Therefore, it is required to apply more parameters to understand the causes of the ionospheric TEC variations and investigate whether ionospheric variations are caused by earthquakes.
Long-Periodic Analysis of Boresight Misalignment of Ziyuan3-01 Three-Line Camera
Authors: Zhu Xiaoyong , Tang Xinming , Zhang Guo , Liu Bin , Hu Wenmin , Pan Hongbo
Published: February 2022

The Ziyuan3-01 (ZY3-01) satellite is China’s first civilian stereo surveying and mapping satellite to meet the 1:50,000 scale mapping requirements, and has been operated in orbit for 10 years. The boresight misalignment of the three-line camera (TLC) is an essential factor affecting the geolocation accuracy, which is a principal concern for stereo mapping satellites. However, the relative relationships of TLC are often regarded as fixed for the same ground scene in most traditional geometric calibrations, without considering the on-orbit long-periodic changes. In this paper, we propose a long-periodic method to analyze and estimate the boresight misalignments between three cameras, with the attitude estimation of a nadir (NAD) camera as the benchmark. Offsets and drifts of the three cameras were calculated and calibrated with different compensation models using scale invariant feature transform (SIFT) points as the ground control. Ten simultaneous NAD–Forward (FWD)–Backward (BWD) imagery of the ZY3-01 satellite acquired from 2012 to 2020 were selected to verify the long-periodic changes in TLC boresight misalignments. The results indicate that the boresight alignment angles of ZY3-01 TLC are dynamic during the long-periodic flight, but the structure of TLC is stable for the misalignments of both FWD and BWD within only 7 arc seconds, which can provide a positive reference for subsequent satellite design and long-periodic on-orbit geometric calibration.
Harmonization of Multi-Mission High-Resolution Time Series: Application to BELAIR
Authors: Swinnen Else , Sterckx Sindy , Wirion Charlotte , Verbeiren Boud , Wens Dieter
Published: February 2022

High-resolution data are increasingly used for various applications, yet the revisit time is still low for some applications, particularly in frequently cloud-covered areas. Therefore, sensors are often combined, which raises issues on data consistency. In this study, we start from L1 to L3 data, and investigate the impact of harmonization measures, correcting for difference in radiometric gain and spectral response function (SRF), and the use of a common processing chain with the same atmospheric correction for Sentinel-2A/B, Landsat-8, DEIMOS-1, and Proba-V center cameras. These harmonization measures are evaluated step-wise in two applications: (1) agricultural monitoring, and (2) hydrological modelling in an urban context, using biophysical parameters and NDVI. The evaluation includes validation with in situ data, relative consistency analysis between different sensors, and the evaluation of the time series noise. A higher accuracy was not obtained when validating against in situ data. Yet, the relative analysis and the time series noise analysis clearly demonstrated that the largest improvement in consistency between sensors was obtained when applying the same atmospheric correction to all sensors. The gain correction obtained and its impact on the results was small, indicating that the sensors were already well calibrated. We could not demonstrate an improved consistency after SRF correction. It is likely that other factors, such as anisotropy effects, play a larger role, requiring further research.
AFE-RCNN: Adaptive Feature Enhancement RCNN for 3D Object Detection
Authors: Shuang Feng , Huang Hanzhang , Li Yong , Qu Rui , Li Pei
Published: February 2022

The point clouds scanned by lidar are generally sparse, which can result in fewer sampling points of objects. To perform precise and effective 3D object detection, it is necessary to improve the feature representation ability to extract more feature information of the object points. Therefore, we propose an adaptive feature enhanced 3D object detection network based on point clouds (AFE-RCNN). AFE-RCNN is a point-voxel integrated network. We first voxelize the raw point clouds and obtain the voxel features through the 3D voxel convolutional neural network. Then, the 3D feature vectors are projected to the 2D bird’s eye view (BEV), and the relationship between the features in both spatial dimension and channel dimension is learned by the proposed residual of dual attention proposal generation module. The high-quality 3D box proposals are generated based on the BEV features and anchor-based approach. Next, we sample key points from raw point clouds to summarize the information of the voxel features, and obtain the key point features by the multi-scale feature extraction module based on adaptive feature adjustment. The neighboring contextual information is integrated into each key point through this module, and the robustness of feature processing is also guaranteed. Lastly, we aggregate the features of the BEV, voxels, and point clouds as the key point features that are used for proposal refinement. In addition, to ensure the correlation among the vertices of the bounding box, we propose a refinement loss function module with vertex associativity. Our AFE-RCNN exhibits comparable performance on the KITTI dataset and Waymo open dataset to state-of-the-art methods. On the KITTI 3D detection benchmark, for the moderate difficulty level of the car and the cyclist classes, the 3D detection mean average precisions of AFE-RCNN can reach 81.53% and 67.50%, respectively.