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Open AccessFeature PaperArticle

Occurrence Characteristics and Ecological Risk Assessment of Organophosphorus Compounds in a Wastewater Treatment Plant and Upstream Enterprises

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Water 2022, 14(23), 3942; https://doi.org/10.3390/w14233942 (registering DOI) - 03 Dec 2022

Abstract

Organophosphorus compounds have toxic effects on organisms and the ecosystem. Therefore, it is vital to monitor and control the effluent organophosphorus levels of wastewater treatment plants (WWTPs). This study analyzed the composition and concentration of organophosphorus compounds from the upstream enterprises of a [...] Read more.

Organophosphorus compounds have toxic effects on organisms and the ecosystem. Therefore, it is vital to monitor and control the effluent organophosphorus levels of wastewater treatment plants (WWTPs). This study analyzed the composition and concentration of organophosphorus compounds from the upstream enterprises of a WWTP and conducted ecological risk and toxicity assessments using ECOSAR (ecological structure activity relationship model), T.E.S.T (Toxicity Estimation Software Tool), and risk quotient (RQ) methods. A total of 14 organic phosphorus pollutants were detected in the effluent of the upstream enterprises and WWTP. The concentration of influent total organic phosphorus from the WWTP was 39.5 mg/L, and the effluent total organic phosphorus was merely 0.301 mg/L, indicating that good phosphorus removal was achieved in the WWTP. According to the acute and chronic toxicity analysis, the ECOSAR ecotoxicity assessment showed that 11 kinds of organophosphorus compounds were hazardous to fish, daphnia, and algae in different degrees. Among them, triphenyl phosphine (TPP) had a 96 hr LC50 of 1.00 mg/L for fish and is a substance with high acute toxicity. T.E.S.T evaluates the acute toxicity of each organophosphorus component and the bioconcentration factor (BCF). The evaluation results showed that the LC50 of TPP and octicizer were 0.39 and 0.098 mg/L, respectively, and the concentrations of these two organophosphorus compounds from the effluent of an environmental protection enterprise were as high as 30.4 mg/L and 0.735 mg/L, which exceeded the acute toxicity values and has led to serious hazards to aquatic organisms. The BCF values of each organophosphorus component in the upstream enterprises and the effluent of the WWTP were less than 2000, implying that there was no bioaccumulation effect on aquatic organisms. The developmental toxicity assessment demonstrated that there were nine types of organophosphorus compounds belonging to developmental toxicants, that the presence of developmental toxicants was found in the effluent of each upstream enterprise, and that triethyl phosphate (TEP) was the most common organophosphorus compound. Comparing the RQ of the effluent from various enterprises, it was found that the effluent from the environmental protection enterprise presented the highest degree of environmental hazard, mainly due to the higher toxicity of TEP and octicizer. Full article

(This article belongs to the Special Issue Low-Carbon, Zero-Carbon and Negative-Carbon Wastewater Treatment Technology and Operation Strategies)

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Open AccessArticle

Characterization of New Egyptian Linseed Varieties and the Effects of Roasting on Their Pigments, Tocochromanols, Phytosterols, Omega-3 Fatty Acids, and Stability

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Minar Mahmoud M. Hassanein

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Adel Gabr Abdel-Razek

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Sherine Mohamed Affifi

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Ying Qian

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Elżbieta Radziejewska-Kubzdela

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Aleksander Siger

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Magdalena Rudzińska

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Ghada Ahmed Abo-Elwafa

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Anna Grygier

Molecules 2022, 27(23), 8526; https://doi.org/10.3390/molecules27238526 (registering DOI) - 03 Dec 2022

Abstract

The purpose of this study was to explore the effects of roasting linseeds on the pigment, lipid profile, bioactive components, and oxidative stability of the extracted oils. The linseed varieties Giza 11, Giza 12, Sakha 3, and Sakha 6 were roasted at 180 [...] Read more.

The purpose of this study was to explore the effects of roasting linseeds on the pigment, lipid profile, bioactive components, and oxidative stability of the extracted oils. The linseed varieties Giza 11, Giza 12, Sakha 3, and Sakha 6 were roasted at 180 °C for 10 min, and the oils were extracted by cold pressing. The results showed that, after roasting, there was an increase in oil percentage and peroxide value, as well as small increases in p-anisidine and acid values. Roasting also caused an increase in chlorophyll content, while lutein and β-carotene tend to slightly decrease, except in the Giza 11 variety. The total phenolics content was markedly enhanced after roasting. Omega-3 fatty acids were not affected by the roasting process. The total amounts of tocochromanol were found to decrease in the Giza 12 and Sakha 6 varieties after roasting. Plastochromanol-8 increased in all varieties after roasting. The phytosterol composition was minimally affected by roasting. Roasting enhanced the stability of the extracted oils, increasing the induction period and decreasing EC50 values. These results may thus help to discriminate between the different linseed varieties and serve to recommend the use of roasting to enhance the oxidative stability of extracted oil. Full article

(This article belongs to the Special Issue Analysis of Bioactive Compounds in Food)

Open AccessArticle

Nucleoside Analogs and Perylene Derivatives Modulate Phase Separation of SARS-CoV-2 N Protein and Genomic RNA In Vitro

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Anastasia Khandazhinskaya

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Liubov Kozlovskaya

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Nataliya Miropolskaya

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Int. J. Mol. Sci. 2022, 23(23), 15281; https://doi.org/10.3390/ijms232315281 (registering DOI) - 03 Dec 2022

Abstract

The life cycle of severe acute respiratory syndrome coronavirus 2 includes several steps that are supposedly mediated by liquid–liquid phase separation (LLPS) of the viral nucleocapsid protein (N) and genomic RNA. To facilitate the rational design of LLPS-targeting therapeutics, we modeled N-RNA biomolecular [...] Read more.

The life cycle of severe acute respiratory syndrome coronavirus 2 includes several steps that are supposedly mediated by liquid–liquid phase separation (LLPS) of the viral nucleocapsid protein (N) and genomic RNA. To facilitate the rational design of LLPS-targeting therapeutics, we modeled N-RNA biomolecular condensates in vitro and analyzed their sensitivity to several small-molecule antivirals. The model condensates were obtained and visualized under physiological conditions using an optimized RNA sequence enriched with N-binding motifs. The antivirals were selected based on their presumed ability to compete with RNA for specific N sites or interfere with non-specific pi–pi/cation–pi interactions. The set of antivirals included fleximers, 5′-norcarbocyclic nucleoside analogs, and perylene-harboring nucleoside analogs as well as non-nucleoside amphiphilic and hydrophobic perylene derivatives. Most of these antivirals enhanced the formation of N-RNA condensates. Hydrophobic perylene derivatives and 5′-norcarbocyclic derivatives caused up to 50-fold and 15-fold enhancement, respectively. Molecular modeling data argue that hydrophobic compounds do not hamper specific N-RNA interactions and may promote non-specific ones. These findings shed light on the determinants of potent small-molecule modulators of viral LLPS. Full article

(This article belongs to the Special Issue Molecular Regulation and Mechanism of Ribonucleoprotein Complexes)

Open AccessArticle

Social Media Web 2.0 Tools Adoption in Language and Literacy Development in Early Years: A Scoping Review

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Children 2022, 9(12), 1901; https://doi.org/10.3390/children9121901 (registering DOI) - 03 Dec 2022

Abstract

Social media tools are increasingly used in child’s language and literacy development in early years. However, few researchers shed light on effectiveness and the practice that the EC professionals and teachers have adopted in ECE settings and other related contexts. This scoping review [...] Read more.

Social media tools are increasingly used in child’s language and literacy development in early years. However, few researchers shed light on effectiveness and the practice that the EC professionals and teachers have adopted in ECE settings and other related contexts. This scoping review synthesized and evaluated the literature on social media integration in language and literacy development in ECE in the last decade, to provide a clearer picture on what social media tools were used, how they were used, and whether they were effective. Results showed that a wide-range of social media tools were used in diverse learning activities; however, few studies designed the learning activities with the guidance of an evidence-based teaching method or pedagogical framework. Full article

(This article belongs to the Special Issue Strengthening Social Media Tools in Early Childhood Development: Evidence-Based Research in Multilingual and Multicultural Contexts)

Open AccessArticle

Colloidal Aqueous Dispersions of Methyl (Meth)Acrylate-Grafted Polyvinyl Alcohol Designed for Thin Film Applications

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Coatings 2022, 12(12), 1882; https://doi.org/10.3390/coatings12121882 (registering DOI) - 03 Dec 2022

Abstract

In this paper, the aqueous copolymer dispersions of methyl (meth)acrylate-grafted poly(vinyl alcohol) are in situ synthesized and studied as a promising platform for the deposition of thin films with advanced applications. A series of dispersions of the varied copolymer structure and composition are [...] Read more.

In this paper, the aqueous copolymer dispersions of methyl (meth)acrylate-grafted poly(vinyl alcohol) are in situ synthesized and studied as a promising platform for the deposition of thin films with advanced applications. A series of dispersions of the varied copolymer structure and composition are obtained at mild reaction conditions by carrying out a redox polymerization at a different monomer-to-PVA ratio and initiator concentration. The obtained colloidal particles are characterized by Fourier transformed infrared spectroscopy, nuclear magnetic resonance, dynamic light scattering, and transmission electron microscopy. The copolymer dispersions are further used for deposition of thin films on silicon substrates. The films are characterized optically through reflectance measurements and non-linear curve fitting. Their suitability for the optical sensing of acetone vapors is confirmed by reflectance measurements before and during their exposure to analyte vapors. The cross sensitivity, sensing repeatability, and recovery of the sensitive films are discussed. Full article

(This article belongs to the Collection Feature Paper Collection in Thin Films)

Open AccessCommunication

Offline Imagery Checks for Remote Drone Usage

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Roxane J. Francis

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Kate J. Brandis

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Justin A. McCann

Drones 2022, 6(12), 395; https://doi.org/10.3390/drones6120395 (registering DOI) - 03 Dec 2022

Abstract

Drones are increasingly used for a wide range of applications including mapping, monitoring, detection, tracking and videography. Drone software and flight mission programs are, however, still largely marketed for “urban” use such as property photography, roof inspections or 3D mapping. As a result, [...] Read more.

Drones are increasingly used for a wide range of applications including mapping, monitoring, detection, tracking and videography. Drone software and flight mission programs are, however, still largely marketed for “urban” use such as property photography, roof inspections or 3D mapping. As a result, much of the flight mission software is reliant upon an internet connection and has built-in cloud-based services to allow for the mosaicking of imagery as a direct part of the image collection process. Another growing use for drones is in conservation, where drones are monitoring species and habitat change. Naturally, much of this work is undertaken in areas without internet connection. Working remotely increases field costs, and time in the field is often aligned with specific ecological seasons. As a result, pilots in these scenarios often have only one chance to collect appropriate data and an opportunity missed can mean failure to meet research aims and contract deliverables. We provide a simple but highly practical piece of code allowing drone pilots to quickly plot the geographical position of captured photographs and assess the likelihood of the successful production of an orthomosaic. Most importantly, this process can be performed in the field with no reliance on an internet connection, and as a result can highlight any missing sections of imagery that may need recollecting, before the opportunity is missed. Code is written in R, a familiar software to many ecologists, and provided on a GitHub repository for download. We recommend this data quality check be integrated into a pilot’s standard image capture process for the dependable production of mosaics and general quality assurance of drone collected imagery. Full article

(This article belongs to the Section Drone Communications)

Open AccessArticle

On the Correspondence between Subshifts of Finite Type and Statistical Mechanics Models

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Luis Armando Corona

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Raúl Salgado García

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Edgardo Ugalde

Entropy 2022, 24(12), 1772; https://doi.org/10.3390/e24121772 (registering DOI) - 03 Dec 2022

Abstract

Several classical problems in symbolic dynamics concern the characterization of the simplex of measures of maximal entropy. For subshifts of finite type in higher dimensions, methods of statistical mechanics are ideal for dealing with these problems. R. Burton and J. Steif developed a [...] Read more.

Several classical problems in symbolic dynamics concern the characterization of the simplex of measures of maximal entropy. For subshifts of finite type in higher dimensions, methods of statistical mechanics are ideal for dealing with these problems. R. Burton and J. Steif developed a strategy to construct examples of strongly irreducible subshifts of finite type admitting several measures of maximal entropy. This strategy exploits a correspondence between equilibrium statistical mechanics and symbolic dynamics—a correspondence which was later formalized by O. Häggström. In this paper, we revisit and discuss this correspondence with the aim of presenting a simplified version of it and present some applications of rigorous results concerning the Potts model and the six-vertex model to symbolic dynamics, illustrating in this way the possibilities of this correspondence. Full article

(This article belongs to the Section Statistical Physics)

Open AccessArticle

A Novel Safety Risk Assessment Based on Fuzzy Set Theory and Decision Methods in High-Rise Buildings

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Buildings 2022, 12(12), 2126; https://doi.org/10.3390/buildings12122126 (registering DOI) - 03 Dec 2022

Abstract

The high-rise construction industry has particular features, such as prolonged construction periods and constant change in the workplace. These features may have turned it into the most dangerous industry, given its significant mortality rate. This research aims to identify effective criteria for high-rise [...] Read more.

The high-rise construction industry has particular features, such as prolonged construction periods and constant change in the workplace. These features may have turned it into the most dangerous industry, given its significant mortality rate. This research aims to identify effective criteria for high-rise buildings’ safety issues and rank the most critical risks to level up the safety of these projects. This research is divided into two phases: In Phase I, the effective criteria in the literature on the occurrence of accidents are divided into three main classes, and their weights are determined using the best–worst method. In Phase II, the existing risks are ranked using the fuzzy Vlse Kriterijumska Optimizacija Kompromisno Resenje (FUZZY VIKOR) method. The results indicate that safety training and monitoring, which account for approximately 35% of the total weight, are the most influential criteria for risk occurrence. The risk of falling from heights has been ranked first as the most critical safety risk according to the eight criteria, including safety training and monitoring. The total weight of criteria in which falling from height attains the first rank equals 0.688. Damages caused by working with manual tools and equipment have the highest priority in four criteria, and the total weight of 0.1591 attains the second rank. The results of this research comply with the current situation of the construction industry and pave the way for future research on high-rise construction projects. Full article

(This article belongs to the Special Issue Proactive and Advanced Research on Construction Safety Management)

Open AccessArticle

Triggers and Coping Strategies for Fear of Cancer Recurrence in Cancer Survivors: A Qualitative Study

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Curr. Oncol. 2022, 29(12), 9501-9510; https://doi.org/10.3390/curroncol29120746 (registering DOI) - 03 Dec 2022

Abstract

Background: Fear of cancer recurrence (FCR) has been demonstrated to be one of the most frequently reported unmet psychological needs among cancer survivors. The aim of this study was to explore and describe the potential triggers and coping strategies for FCR in Chinese [...] Read more.

Background: Fear of cancer recurrence (FCR) has been demonstrated to be one of the most frequently reported unmet psychological needs among cancer survivors. The aim of this study was to explore and describe the potential triggers and coping strategies for FCR in Chinese cancer survivors. Methods: The study process was conducted using an interpretive phenomenological research method, and Chinese cancer survivors were interviewed face-to-face in a semi-structured interview, using purposive sampling combined with a maximum variance sampling strategy, and the interviews were transcribed, organized, and analyzed by applying Giorgi analysis with the help of NVivo11 software. Results: A total of 10 participants, 4 males and 6 females, were interviewed. Three themes emerged in terms of potential triggers for FCR: (1) intrusive thoughts; (2) disease symptoms; and (3) awaiting medical examination. Two themes regarding positive coping and avoidance coping emerged with regard to coping strategies adopted by cancer survivors when experiencing FCR. Under these 2 themes were 5 sub-themes: (1) seeking medical support; (2) self-health management; (3) spiritual coping; (4) unaccompanied toleration; and (5) attention shifting. Conclusion: FCR as the most common psychological problem for cancer survivors, and it should be given more attention. Early identification and precise intervention for potential triggers of FCR may prevent the emergence and development of FCR. The guidance toward and cultivation of positive coping strategies when cancer survivors experience FCR could be an important direction in future nursing education. Full article

(This article belongs to the Special Issue Health Behaviours, Illness Representations, Quality of Life, Coping, and Fear of Cancer Recurrence in Those Affected by Cancer)

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Open AccessArticle

Bidirectional Terahertz Vortex Beam Regulator

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Materials 2022, 15(23), 8639; https://doi.org/10.3390/ma15238639 (registering DOI) - 03 Dec 2022

Abstract

Most of the reported vortex beam generators with orbital angular momentum (OAM) in the terahertz region only operate in either the reflection mode or the transmission mode, which greatly limits the integration and application in terahertz technology systems. Herein, we propose a full-space [...] Read more.

Most of the reported vortex beam generators with orbital angular momentum (OAM) in the terahertz region only operate in either the reflection mode or the transmission mode, which greatly limits the integration and application in terahertz technology systems. Herein, we propose a full-space vortex beam regulator at two different frequencies. By changing the VO₂ phase transition state, the transmission and reflection mode OAM beams can be flexibly controlled by a single metasurface. For the transmission mode, the proposed structure realizes an OAM beam at the topological charges of l = 1 and 2 at 0.6 THz and 1.4 THz. For the reflection mode, our structure generates an OAM beam at the topological charges of l = 1 and 2 at 0.9 THz and 1.5 THz. Based on the superposition theorem and convolution operation principle, the regulation of an OAM vortex beam with a specific deflection angle and a symmetrical deflection OAM vortex beam are realized. The designed metasurface integrates multiple transmitted and reflected vortex beam functions in full space and has potential application in different terahertz systems. Full article

(This article belongs to the Special Issue Design and Applications of Terahertz Metamaterials)

Open AccessArticle

Theranostic Investigation of Gadolinium-159 for Hepatocellular Carcinoma: Monte Carlo Simulation Study

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Ahmed Sadeq Musa

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Muhammad Fahmi Rizal Abdul Hadi

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Nabeel Ibrahim Ashour

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Nurul Ab. Aziz Hashikin

Appl. Sci. 2022, 12(23), 12396; https://doi.org/10.3390/app122312396 (registering DOI) - 03 Dec 2022

Abstract

Gadolinium-159 (¹⁵⁹Gd) is a beta emitter with appropriate energy for therapeutic application. However, this radioisotope additionally emits gamma rays, enabling the distribution of ¹⁵⁹Gd to be detected by a gamma camera after each therapeutic administration. The current research is innovative [...] Read more.

Gadolinium-159 (¹⁵⁹Gd) is a beta emitter with appropriate energy for therapeutic application. However, this radioisotope additionally emits gamma rays, enabling the distribution of ¹⁵⁹Gd to be detected by a gamma camera after each therapeutic administration. The current research is innovative in the investigation of ¹⁵⁹Gd as a theranostic radioisotope in the radioembolization of HCC using Monte Carlo (MC) simulation. For ¹⁵⁹Gd therapeutic investigation, various patient scenarios including varying tumour involvement (TI), tumour-to-normal liver uptake ratio (T/N), and lung shunting (LS) were simulated using Geant4 MC to estimate the absorbed doses to organs at risk. For ¹⁵⁹Gd planar imaging investigation, the SPECTHead example from GATEContrib (GitHub) was utilized, and inside a liver a tumour was created and placed inside a torso phantom and simulated using GATE MC simulation. The majority of ¹⁵⁹Gd absorbed doses by normal liver and lungs were less than the maximum dose limitations of 70 Gy and 30 Gy, respectively. Absorbed doses to other organs were observed to be below 1 Gy. The utilization of 58 keV and 363.54 keV photopeaks in combination produced optimal planar imaging of ¹⁵⁹Gd. This research gives new insights into the use of ¹⁵⁹Gd as a theranostic radioisotope, with the potential to be used as an Yttrium-90 (⁹⁰Y) alternative for liver radioembolization. Full article

(This article belongs to the Special Issue Medical Physics: Latest Advances and Prospects)

Open AccessArticle

Population Perspectives on Impact of the COVID-19 Pandemic on Essential Health Services—Behavioral Insights from the Federation of Bosnia and Herzegovina

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Šeila Cilović-Lagarija

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Katrine Bach Habersaat

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Catherine Smallwood

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Ardita Tahirukaj

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Dorit Nitzan

Behav. Sci. 2022, 12(12), 495; https://doi.org/10.3390/bs12120495 (registering DOI) - 03 Dec 2022

Abstract

The aim of this study was to analyze the impact of the COVID-19 pandemic on patterns of use of essential health services (EHS), health-seeking behaviors, and population health and wellbeing in the Federation of Bosnia and Herzegovina (FBiH) from the perspective of its [...] Read more.

The aim of this study was to analyze the impact of the COVID-19 pandemic on patterns of use of essential health services (EHS), health-seeking behaviors, and population health and wellbeing in the Federation of Bosnia and Herzegovina (FBiH) from the perspective of its adult population. A population-based survey was implemented in the FBiH in December 2020 on a sample of 1068 adults. Overall, 64% of respondents received care, significantly more being women (67% vs. 61%, p = 0.046), those with a chronic disease (CD) (75% vs. 65%, p < 0.001), and of an older age (58% in 18–34 vs. 67% in older, p = 0.031). These groups also postponed care more often (39% in 55+ vs. 31% in 18–34 years old, p = 0.01; 55% with CD vs. 31% without, p < 0.001; and 43% in females vs. 32% males, p < 0.001). Main reasons for postponing care were lack of available appointments and fear of infection. The presence of a CD was the strongest predictor of need, access, and disruptions of health care. Respondents reported increased expenses for medicines (40%) and health services (30%). The findings of the survey add user insights into EHS disruptions to existing health statistics and other data and may be used to inform strategies for mitigating the impact of COVID-19 on the disruption of health care services, strengthening health system preparedness and building resilience for future emergencies. Full article

(This article belongs to the Special Issue Preventive Behaviors toward COVID-19: Antecedents, Compliance, and Psychological Impact)

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Open AccessArticle

Experimental Investigation of the Influence of Freeze–Thaw Mode on Damage Characteristics of Sandstone

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Appl. Sci. 2022, 12(23), 12395; https://doi.org/10.3390/app122312395 (registering DOI) - 03 Dec 2022

Abstract

The influence of rock weathering caused by freezing–thawing on stone cultural relics cannot be ignored. For immovable stone cultural relics, different parts under different environmental conditions will be under different freeze–thaw actions and suffer different degrees of damage. In this paper, three typical [...] Read more.

The influence of rock weathering caused by freezing–thawing on stone cultural relics cannot be ignored. For immovable stone cultural relics, different parts under different environmental conditions will be under different freeze–thaw actions and suffer different degrees of damage. In this paper, three typical freeze–thaw cycle tests of sandstone are designed, namely immersion test, capillary action test, and periodic saturation test. The macroscopic and microscopic morphologies of rock samples under different freeze–thaw cycles were analyzed. Weathering indicators such as porosity, water content, wave velocity, and surface hardness were tested, as well as uniaxial compressive strength. The variation law of weathering index and uniaxial compressive strength under different freezing–thawing cycles was obtained, and the quantitative relationship between each index parameter was further analyzed. The results show that under different freezing–thawing conditions, the apparent morphology of rock samples is different, and the trend of weathering indexes is similar, but the rate of change is different. The water content of rock has a great influence on the test results of wave velocity but has little influence on the surface hardness. The function relationship between weathering index and compressive strength under different freezing–thawing modes is similar, but the fitting parameters are different. Finally, the strength and wave velocity damage factors were used to quantitatively evaluate the degree of rock weathering. The results show that the immersion freeze–thaw damage is the highest, the periodic saturated freeze–thaw damage is the second highest, and the capillary freeze–thaw damage is the least highest. This is consistent with the field observation results. The conclusion of this paper can provide reference for the detection of stone cultural relics and provides a scientific basis for the anti-weathering protection of stone cultural relics. Full article

(This article belongs to the Special Issue Approaches and Challenges in Diagnostics and Conservation of Cultural Heritage)

Open AccessArticle

The Essential Oil from the Resurrection Plant Myrothamnus moschatus is Effective against Arthropods of Agricultural and Medical Interest

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Rianasoambolanoro Rakotosaona

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Renato Ricciardi

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Giovanni Benelli

Pharmaceuticals 2022, 15(12), 1511; https://doi.org/10.3390/ph15121511 (registering DOI) - 03 Dec 2022

Abstract

This work aimed to evaluate the chemical composition, insecticidal and acaricidal potential of the essential oil (EO) obtained from the resurrection plant Myrothamnus moschatus (Baill.) Baill. (Myrothamnaceae) from Madagascar. The EO bioactivity was evaluated against selected arthropod pests and vectors of agricultural and [...] Read more.

This work aimed to evaluate the chemical composition, insecticidal and acaricidal potential of the essential oil (EO) obtained from the resurrection plant Myrothamnus moschatus (Baill.) Baill. (Myrothamnaceae) from Madagascar. The EO bioactivity was evaluated against selected arthropod pests and vectors of agricultural and public health relevance. The most abundant volatile compounds were trans-pinocarveol (37.7 ± 4.2%) and pinocarvone (20.8 ± 3.1%), similar to the EO of the chemotype collected from the same region. Lethal concentrations (LC₅₀) or doses (LD₅₀) from acute toxicity tests were estimated for Musca domestica (L.) adults at 22.7 µg adult⁻¹, for Spodoptera littoralis (Boisduval) larvae at 35.6 µg larva⁻¹, for Culex quinquefasciatus (Say) at 43.6 µg mL⁻¹, for adults of Metopolophium dirhodum (Walker) at 2.4 mL L⁻¹, and for adults of Tetranychus urticae (Koch) at 1.2 mL L⁻¹. The good insecticidal and acaricidal activities determined in this work may open a new perspective on the use of this plant as a source of botanical insecticide ingredients. The exploitation of this species could also be important for the African economy, helping local farmers cultivating this plant. Full article

(This article belongs to the Special Issue Application of Gas Chromatography to Detect Volatile Secondary Metabolites from Natural Products of Pharmacological Interest)

Open AccessCommunication

PET Imaging of Fructose Metabolism in a Rodent Model of Neuroinflammation with 6-[¹⁸F]fluoro-6-deoxy-D-fructose

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Molecules 2022, 27(23), 8529; https://doi.org/10.3390/molecules27238529 (registering DOI) - 03 Dec 2022

Abstract

Fluorine-18 labeled 6-fluoro-6-deoxy-D-fructose (6-[¹⁸F]FDF) targets the fructose-preferred facilitative hexose transporter GLUT5, which is expressed predominantly in brain microglia and activated in response to inflammatory stimuli. We hypothesize that 6-[¹⁸F]FDF will specifically image microglia following neuroinflammatory insult. 6-[¹⁸F]FDF [...] Read more.

Fluorine-18 labeled 6-fluoro-6-deoxy-D-fructose (6-[¹⁸F]FDF) targets the fructose-preferred facilitative hexose transporter GLUT5, which is expressed predominantly in brain microglia and activated in response to inflammatory stimuli. We hypothesize that 6-[¹⁸F]FDF will specifically image microglia following neuroinflammatory insult. 6-[¹⁸F]FDF and, for comparison, [¹⁸F]FDG were evaluated in unilateral intra-striatal lipopolysaccharide (LPS)-injected male and female rats (50 µg/animal) by longitudinal dynamic PET imaging in vivo. In LPS-injected rats, increased accumulation of 6-[¹⁸F]FDF was observed at 48 h post-LPS injection, with plateaued uptake (60–120 min) that was significantly higher in the ipsilateral vs. contralateral striatum (0.985 ± 0.047 and 0.819 ± 0.033 SUV, respectively; p = 0.002, n = 4M/3F). The ipsilateral–contralateral difference in striatal 6-[¹⁸F]FDF uptake expressed as binding potential (BP_SRTM) peaked at 48 h (0.19 ± 0.11) and was significantly decreased at one and two weeks. In contrast, increased [¹⁸F]FDG uptake in the ipsilateral striatum was highest at one week post-LPS injection (BP_SRTM = 0.25 ± 0.06, n = 4M). Iba-1 and GFAP immunohistochemistry confirmed LPS-induced activation of microglia and astrocytes, respectively, in ipsilateral striatum. This proof-of-concept study revealed an early response of 6-[¹⁸F]FDF to neuroinflammatory stimuli in rat brain. 6-[¹⁸F]FDF represents a potential PET radiotracer for imaging microglial GLUT5 density in brain with applications in neuroinflammatory and neurodegenerative diseases. Full article

(This article belongs to the Special Issue Radiopharmaceuticals)

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Open AccessPerspective

Thermal Properties of Energetic Materials—What Are the Sources of Discrepancies?

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Agnieszka Stolarczyk

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Tomasz Jarosz

Fire 2022, 5(6), 206; https://doi.org/10.3390/fire5060206 (registering DOI) - 03 Dec 2022

Abstract

Thermal analysis is widely used to investigate the properties of a variety of energetic materials, including the mutual compatibility of components of energetic material mixtures. Although thermal analysis methods are a valuable source of information about energetic materials, their use requires careful consideration [...] Read more.

Thermal analysis is widely used to investigate the properties of a variety of energetic materials, including the mutual compatibility of components of energetic material mixtures. Although thermal analysis methods are a valuable source of information about energetic materials, their use requires careful consideration of the employed methodology, as well as an understanding of the thermally induced processes taking place within energetic materials. Several case studies involving the study of energetic materials are presented, in order to highlight some of the most relevant issues in the application of thermal analysis methods. Some recommendations about the application of thermal analysis methods and accompanying methodologies for estimating other properties of energetic materials are also included. Full article

(This article belongs to the Section Mathematical Modelling and Numerical Simulation of Combustion and Fire)

Open AccessArticle

Design of Precision-Aware Subthreshold-Based MOSFET Voltage Reference

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Shuzheng Mu

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Pak Kwong Chan

Sensors 2022, 22(23), 9466; https://doi.org/10.3390/s22239466 (registering DOI) - 03 Dec 2022

Abstract

A new precision-aware subthreshold-based MOSFET voltage reference is presented in this paper. The circuit was implemented TSMC−40 nm process technology. It consumed 9.6 at the supply voltage of 1.2 V. In this proposed work, by utilizing subthreshold-based MOSFET instead of bipolar junction transistor [...] Read more.

A new precision-aware subthreshold-based MOSFET voltage reference is presented in this paper. The circuit was implemented TSMC−40 nm process technology. It consumed 9.6 at the supply voltage of 1.2 V. In this proposed work, by utilizing subthreshold-based MOSFET instead of bipolar junction transistor (BJT), relatively lower power consumption was obtained in the design while offering comparable precision to that offered by its BJT counterpart. Through the proposed second-order compensation, it achieved the temperature coefficient (T.C.) of 3.0 ppm/ in the TT corner case and a 200-sample Monte-Carlo T.C. of 12.51 ppm/ from −40 to 90 . This shows robust temperature insensitivity. The process sensitivity of without and with trimming was 2.85% and 0.75%, respectively. The power supply rejection (PSR) was 71.65 dB at 100 Hz and 52.54 dB at 10 MHz. The Figure-of-Merit (FOM) for the total variation in output voltage was comparable with representative BJT circuits and better than subthreshold-based MOSFET circuits. Due to low T.C., low process sensitivity, and simplicity of the circuit architecture, the proposed work will be useful for sensor circuits with stringent requirements or other analog circuits that require high precision applications. Full article

(This article belongs to the Special Issue Feature Papers in Electronic Sensors)

Open AccessArticle

Novel Genes Involved in Hypertrophic Cardiomyopathy: Data of Transcriptome and Methylome Profiling

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Int. J. Mol. Sci. 2022, 23(23), 15280; https://doi.org/10.3390/ijms232315280 (registering DOI) - 03 Dec 2022

Abstract

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease; its pathogenesis is still being intensively studied to explain the reasons for the significant genetic and phenotypic heterogeneity of the disease. To search for new genes involved in HCM development, we analyzed gene [...] Read more.

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease; its pathogenesis is still being intensively studied to explain the reasons for the significant genetic and phenotypic heterogeneity of the disease. To search for new genes involved in HCM development, we analyzed gene expression profiles coupled with DNA methylation profiles in the hypertrophied myocardia of HCM patients. The transcriptome analysis identified significant differences in the levels of 193 genes, most of which were underexpressed in HCM. The methylome analysis revealed 1755 nominally significant differentially methylated positions (DMPs), mostly hypomethylated in HCM. Based on gene ontology enrichment analysis, the majority of biological processes, overrepresented by both differentially expressed genes (DEGs) and DMP-containing genes, are involved in the regulation of locomotion and muscle structure development. The intersection of 193 DEGs and 978 DMP-containing genes pinpointed eight common genes, the expressions of which correlated with the methylation levels of the neighboring DMPs. Half of these genes (AUTS2, BRSK2, PRRT1, and SLC17A7), regulated by the mechanism of DNA methylation, were underexpressed in HCM and were involved in neurogenesis and synapse functioning. Our data, suggesting the involvement of innervation-associated genes in HCM, provide additional insights into disease pathogenesis and expand the field of further research. Full article

(This article belongs to the Special Issue The Impact of Altered Metabolism on Cardiac Development and Disease)

Open AccessArticle

Racial Differences in Breastfeeding on the Mississippi Gulf Coast: Making Sense of a Promotion-Prevalence Paradox with Cross-Sectional Data

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Healthcare 2022, 10(12), 2444; https://doi.org/10.3390/healthcare10122444 (registering DOI) - 03 Dec 2022

Abstract

Breastfeeding is less prevalent among African American women than their white peers. Moreover, breastfeeding rates in the South lag behind those in other regions of the U.S. Consequently, various efforts have been undertaken to promote breastfeeding among groups for which this practice is [...] Read more.

Breastfeeding is less prevalent among African American women than their white peers. Moreover, breastfeeding rates in the South lag behind those in other regions of the U.S. Consequently, various efforts have been undertaken to promote breastfeeding among groups for which this practice is less common. This study examines African American and white racial disparities concerning (1) exposure to breastfeeding promotional information and (2) reported prevalence of breastfeeding in primary social networks. The survey combines a randomly selected sample of adults representative of the population and a non-random oversample of African Americans in a predominantly rural tri-county area on the Mississippi Gulf Coast. An initial wave of 2019 Mississippi REACH Social Climate Survey data collected under the auspices of the CDC-funded REACH program (Mississippi’s Healthy Families, Mothers, and Babies Initiative; 2018–2023) is used to examine racial disparities in these two key outcomes for Mississippians in Hancock, Harrison, and Jackson counties. The results show that African American respondents are more likely to be exposed to breastfeeding promotional messages than their white counterparts. However, the reported prevalence of breastfeeding in African American respondents’ primary social networks is significantly lower than that indicated by their white peers. These paradoxical results underscore the limitations of promotional efforts alone to foster breastfeeding. While breastfeeding promotion is important, the reduction of racial disparities in this practice likely requires a multi-pronged effort that involves structural breastfeeding supports (e.g., lactation spaces, peer networking groups, and pro-breastfeeding employment policies and workplaces). This study provides a promising model of innovative methodological approaches to the study of breastfeeding while underscoring the complex nature of racial disparities in lactation prevalence. Full article

(This article belongs to the Special Issue Health and Medical Policy in the Era of Big Data Analytics)

Open AccessArticle

Wnt/β-Catenin Signaling Inhibits Osteogenic Differentiation in Human Periodontal Ligament Fibroblasts

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Ryoya Iizumi

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Michiyo Honda

Biomimetics 2022, 7(4), 224; https://doi.org/10.3390/biomimetics7040224 (registering DOI) - 03 Dec 2022

Abstract

The periodontal ligament is a collagenous tissue that is important for maintaining the homeostasis of cementum and alveolar bone. In tendon cells, Wnt/β-catenin signaling has been reported to regulate the expression level of Scleraxis (Scx) and Mohawk Homeobox (Mkx) [...] Read more.

The periodontal ligament is a collagenous tissue that is important for maintaining the homeostasis of cementum and alveolar bone. In tendon cells, Wnt/β-catenin signaling has been reported to regulate the expression level of Scleraxis (Scx) and Mohawk Homeobox (Mkx) gene and maintain the tissue homeostasis, while its role in the periodontal ligament is unclear. The aim of this study was to investigate the effects of Wnt/β-catenin signaling induced by Wnt-3a stimulation on the inhibition of osteogenic differentiation of human periodontal ligament fibroblasts (HPLFs). During osteogenic differentiation of HPLFs, they formed bone nodules independently of alkaline phosphatase (ALP) activity. After stimulation of Wnt-3a, the expression of β-catenin increased, and nuclear translocation of β-catenin was observed. These data indicate that Wnt-3a activated Wnt/β-catenin signaling. Furthermore, the stimulation of Wnt-3a inhibited the bone nodule formation and suppressed the expression of osteogenic differentiation-related genes such as Runx2, Osteopontin and Osteocalcin, and upregulated the gene expression of Type-I collagen and Periostin (Postn). Scx may be involved in the suppression of osteogenic differentiation in HPLFs. In conclusion, Wnt/β-catenin signaling may be an important signaling pathway that inhibits the osteogenic differentiation in HPLFs by the upregulation of Scx gene expression and downregulation of osteogenic differentiation-related genes. Full article

(This article belongs to the Special Issue Biomimetic Approach to Dental Implants)

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Open AccessArticle

Neomycin, but Not Neamine, Blocks Angiogenic Factor Induced Nitric Oxide Release through Inhibition of Akt Phosphorylation

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Int. J. Mol. Sci. 2022, 23(23), 15277; https://doi.org/10.3390/ijms232315277 (registering DOI) - 03 Dec 2022

Abstract

Angiogenesis, the growth of new blood vessels, is a critical factor of carcinogenesis. Neomycin and neamine, two drugs blocking the nuclear translocation of angiogenin (ANG), have been proven to inhibit tumour growth in vivo. However, the high toxicity of neomycin prevents its therapeutic [...] Read more.

Angiogenesis, the growth of new blood vessels, is a critical factor of carcinogenesis. Neomycin and neamine, two drugs blocking the nuclear translocation of angiogenin (ANG), have been proven to inhibit tumour growth in vivo. However, the high toxicity of neomycin prevents its therapeutic use, thus indicating that the less toxic neamine may be a better candidate. Endothelial cells were cultured on a biocompatible multiple microelectrode array (MMA). The release of NO evoked by ANG or vascular endothelial growth factor (VEGF) was detected electrochemically. The effects of neomycin and neamine on ANG- and VEGF-induced NO releases have been investigated. Neomycin totally blocks NO release for concentrations down to the pM range, probably through the inhibition of the Akt kinase phosphorylation, as revealed by confocal microscopy. On the other hand, both ANG- and VEGF-induced NO releases were not significantly hindered by the presence of high concentrations of neamine. The inhibition of the Akt pathway and NO release are expected to lead to a severe decrease in tissue growth and repair, thus indicating a possible cause for the toxicity of neomycin. Furthermore, the data presented here show that ANG- and VEGF-induced NO releases are not dependent on the nuclear translocation of angiogenin, as these events were not abolished by the presence of neamine. Full article

(This article belongs to the Special Issue Analytical Methods in Biomedical and Environmental Applications: A Molecular Approach)

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Open AccessArticle

Top-Performance Transmission Gratings with Haloalkanes-Based Polymeric Composite Materials

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Riccardo Castagna

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Cristiano Riminesi

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Andrea Di Donato

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Oriano Francescangeli

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Daniele Eugenio Lucchetta

Materials 2022, 15(23), 8638; https://doi.org/10.3390/ma15238638 (registering DOI) - 03 Dec 2022

Abstract

We report on highly transparent holographic phase transmission volume gratings recorded in the visible region at

λ

= 532 nm. The maximum measured diffraction efficiency is higher than 80% with a grating pitch of

Λ

≈ 300 nm and a refractive index modulation [...] Read more.

We report on highly transparent holographic phase transmission volume gratings recorded in the visible region at

λ

= 532 nm. The maximum measured diffraction efficiency is higher than 80% with a grating pitch of

Λ

≈ 300 nm and a refractive index modulation

Δ

n ≈ 0.018. To obtain these results, we used a holographic mixture based on multi-reticulated acrylate and haloalkanes (1-bromo-butane and 1-bromo-hexane) and a synergic combination of camphore-quinone, which has a maximum absorbance at c.a. 470 nm, and R6G, here used as co-initiator, to efficiently initiate the photo-polymerization process. High transparent and high efficient holographic structures based on polymers can find applications in many research fields including integrated optics, sensors, high density data storage and security. Full article

(This article belongs to the Special Issue Optical Properties of Holographic Polymer-Based Composites)

Open AccessArticle

Vehicle Load Identification on Orthotropic Steel Box Beam Bridge Based on the Strain Response Area

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Appl. Sci. 2022, 12(23), 12394; https://doi.org/10.3390/app122312394 (registering DOI) - 03 Dec 2022

Abstract

With the development of the economy and the rapid increase in traffic volume, an overload phenomenon often occurs. This paper studied a vehicle load identification technique based on orthotropic bridge deck stress monitoring data. The strain responses on the lower edge of multiple [...] Read more.

With the development of the economy and the rapid increase in traffic volume, an overload phenomenon often occurs. This paper studied a vehicle load identification technique based on orthotropic bridge deck stress monitoring data. The strain responses on the lower edge of multiple U-ribs were collected under vehicles crossed the deck. Firstly, an index based on the cross-correlation function of strain response between different measurement points on the same U-rib was used to evaluate vehicle speed. Secondly, a cosine similarity index was proposed to locate the transverse position of the vehicle. Finally, the unknown vehicle load was identified on the basis of a calibrated strain response area matrix. The effectiveness and anti-noise performance of the proposed method were verified using numerical simulation. An experimental model was designed and some strain gauges were installed to measure the strain response, and the test was carried out to further verify the algorithm’s performance. Numerical and experimental results show that the proposed method could effectively identify the vehicle load with good anti-noise performance. Moreover, a calibration space was provided to guide practical engineering applications. The proposed method does not damage bridge decks, does not affect traffic, and is economical. Full article

(This article belongs to the Special Issue Advanced Structural Health Monitoring Technologies for Civil Structures)

Open AccessArticle

Identification of Land Use Conflicts in Shandong Province from an Ecological Security Perspective

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Land 2022, 11(12), 2196; https://doi.org/10.3390/land11122196 (registering DOI) - 03 Dec 2022

Abstract

Accurate identification of land use conflicts is an important prerequisite for the rational allocation of land resources and optimizing the production–living–ecological space pattern. Previous studies used suitability assessment and landscape pattern indices to identify land use conflicts. However, research on land use conflict [...] Read more.

Accurate identification of land use conflicts is an important prerequisite for the rational allocation of land resources and optimizing the production–living–ecological space pattern. Previous studies used suitability assessment and landscape pattern indices to identify land use conflicts. However, research on land use conflict identification from the perspective of ecological security is insufficient and not conducive to regional ecological, environmental protection, and sustainable development. Based on ecological security, this study takes Shandong Province as an example and comprehensively evaluates the importance of ecosystem service function and environmental sensitivity. It identifies the ecological source, and extracts ecological corridors with a minimum cumulative resistance model from which ecological security patterns are constructed. It identifies land use conflicts through spatial overlay analysis of arable land and construction land. The results show that: (1) Shandong Province has formed an ecological security pattern of “two ecological barriers, two belts, and eight cores” with an area of 15,987 km². (2) The level of arable land–ecological space conflict is low, at 39.76%. The proportions of serious and moderate conflicts are 13.44% and 26.97%, respectively, distributed primarily on the Jiaodong Peninsula and the low hill areas of Ludong. (3) Construction land–ecological space conflict is reasonably stable and controllable, at 76.39%, occurring mainly around urban construction land, with serious and moderate conflict concentrated in the eastern coastal areas, mainly between rural settlements and ecologically safe space in the region. This study has important theoretical and practical reference values for identifying land use conflicts, protecting regional ecological security, and optimizing land use patterns. Full article

(This article belongs to the Special Issue Eco-Sensitive Areas: Ecosystem Services, Protected Lands, and Current Challenges)

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Open AccessArticle

Improving Temporal Event Scheduling through STEP Perpetual Learning

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Sustainability 2022, 14(23), 16178; https://doi.org/10.3390/su142316178 (registering DOI) - 03 Dec 2022

Abstract

Currently, most machine learning applications follow a one-off learning process: given a static dataset and a learning algorithm, generate a model for a task. These applications can neither adapt to a dynamic and changing environment, nor accomplish incremental task performance improvement continuously. STEP [...] Read more.

Currently, most machine learning applications follow a one-off learning process: given a static dataset and a learning algorithm, generate a model for a task. These applications can neither adapt to a dynamic and changing environment, nor accomplish incremental task performance improvement continuously. STEP perpetual learning, by continuous knowledge refinement through sequential learning episodes, emphasizes the accomplishment of incremental task performance improvement. In this paper, we describe how a personalized temporal event scheduling system SmartCalendar, can benefit from STEP perpetual learning. We adopt the interval temporal logic to represent events’ temporal relationships and determine if events are temporally inconsistent. To provide strategies that approach user preferences for handling temporal inconsistencies, we propose SmartCalendar to recognize, resolve and learn from temporal inconsistencies based on STEP perpetual learning. SmartCalendar has several cornerstones: similarity measures for temporal inconsistency; a sparse decomposition method to utilize historical data; and a loss function based on cross-entropy to optimize performance. The experimental results on the collected dataset show that SmartCalendar incrementally improves its scheduling performance and substantially outperforms comparison methods. Full article

(This article belongs to the Special Issue Artificial Intelligence Applications for Sustainable Urban Living)

Open AccessArticle

Visible Fenton Degradation of Bisphenol A by Boron-Doped, Graphene-Oxide-Coated Nano-Fe₃O₄

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Boxia Liu

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Xiayan Zhang

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Zhi Song

Processes 2022, 10(12), 2582; https://doi.org/10.3390/pr10122582 (registering DOI) - 03 Dec 2022

Abstract

Phenolic pollutants in industrial wastewater are considered to be harmful aromatic compounds. With the development of industry and pharmaceuticals, phenolic pollutants and their derivatives have gradually started to affect people’s daily lives. Therefore, it is necessary to strictly control the content of phenolic [...] Read more.

Phenolic pollutants in industrial wastewater are considered to be harmful aromatic compounds. With the development of industry and pharmaceuticals, phenolic pollutants and their derivatives have gradually started to affect people’s daily lives. Therefore, it is necessary to strictly control the content of phenolic pollutants in industrial wastewater, not only for the natural environment but also for human life. The research optimized the existing treatment methods for classified pollutants, and successfully prepared a heterogeneous photo-Fenton catalyst Fe₃O₄@B-rGO (9.3%). The characterization results of the catalyst showed that the synthesis of the catalyst was successful, and its specific surface area was 11.28 (m²/g), and the pore volume area was 0.137 (m³/g), respectively, which were larger than those of the other two comparative catalysts. In addition, the research conclusion also showed that the catalyst prepared during the research had good catalytic activity, the treatment efficiency of Fe₃O₄@B-rGO (9.3%) to bisphenol A could reach 100%, and the mineralization rate could reach 67.4%. In the reaction, the main active radicals are generated, and catalyst Fe₃O₄@B-rGO (9.3%) can produce more active free radicals compared with Fe₃O₄ and Fe₃O₄@rGO. Full article

(This article belongs to the Special Issue Advanced Liquid Waste and Gas Waste Treatment Processes)

Open AccessArticle

Socio-Technical and Political Complexities: Findings from Two Case Studies of Large IT Project-Based Organizations

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Navid Ahmadi Eftekhari

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Systems 2022, 10(6), 244; https://doi.org/10.3390/systems10060244 (registering DOI) - 03 Dec 2022

Abstract

Information technology (IT) projects are becoming more complex due to technological advancements, increased sociopolitical demand, and competition. In recent years, the project complexity field has attracted increasing attention with diverse strategies and methods proposed to identify, evaluate, and respond to various complexities. This [...] Read more.

Information technology (IT) projects are becoming more complex due to technological advancements, increased sociopolitical demand, and competition. In recent years, the project complexity field has attracted increasing attention with diverse strategies and methods proposed to identify, evaluate, and respond to various complexities. This study aims to identify and prioritize factors contributing to complexity in IT projects by reporting two case studies conducted on large IT organizations. The literature on project complexity informed and guided this exploratory research. The data were collected through 21 semi-structured interviews and analyzed by applying open and axial coding content analysis. Underpinned by complexity theories, 19 factors contributing to the complexity of IT projects were identified, and their importance was highlighted using the Friedman test. The top five factors contributing to IT project complexity were identified as follows: the diversity of stakeholders; technological newness of the project; conflicting goals of stakeholders; variety of product sub-systems and components; and uncertainty of project objectives. This study’s findings contribute to the project management literature and inform practitioners about how to achieve more effective management of complex IT projects. Full article

(This article belongs to the Special Issue Simplifying the Complex: Modeling and Analysis for System Design and Management)

Open AccessArticle

A Noninvasive Sweat Glucose Biosensor Based on Glucose Oxidase/Multiwalled Carbon Nanotubes/Ferrocene-Polyaniline Film/Cu Electrodes

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Micromachines 2022, 13(12), 2142; https://doi.org/10.3390/mi13122142 (registering DOI) - 03 Dec 2022

Abstract

Diabetes remains a great threat to human beings’ health and its world prevalence is projected to reach 9.9% by 2045. At present, the detection methods used are often invasive, cumbersome and time-consuming, thus increasing the burden on patients. In this paper, we propose [...] Read more.

Diabetes remains a great threat to human beings’ health and its world prevalence is projected to reach 9.9% by 2045. At present, the detection methods used are often invasive, cumbersome and time-consuming, thus increasing the burden on patients. In this paper, we propose a novel noninvasive and low-cost biosensor capable of detecting glucose in human sweat using enzyme-based electrodes for point-of-care uses. Specifically, an electrochemical method is applied for detection and the electrodes are covered with multilayered films including ferrocene-polyaniline (F-P), multi-walled carbon nanotubes (MWCNTs) and glucose oxidase (GOx) on Cu substrates (GOx/MWCNTs/F-P/Cu). The coated layers enhance the immobilization of GOx, increase the conductivity of the anode and improve the electrochemical properties of the electrode. Compared with the Cu electrode and the F-P/Cu electrode, a maximum peak current is obtained when the MWCNTs/F-P/Cu electrode is applied. We also study its current response by cyclic voltammetry (CV) at different concentrations (0–2.0 mM) of glucose solution. The best current response is obtained at 0.25 V using chronoamperometry. The effective working lifetime of an electrode is up to 8 days. Finally, to demonstrate the capability of the electrode, a portable, miniaturized and integrated detection device based on the GOx/MWCNTs/F-P/Cu electrode is developed. The results exhibit a short response time of 5 s and a correlation coefficient R² of 0.9847 between the response current of sweat with blood glucose concentration. The LOD is of 0.081 mM and the reproducibility achieved in terms of RSD is 3.55%. The sweat glucose sensor is noninvasive and point-of-care, which shows great development potential in the health examination and monitoring field. Full article

(This article belongs to the Special Issue Biosensors for Biomedical and Environmental Applications)

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