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Open AccessFeature PaperReview
Cholangiocarcinoma Disease Modelling Through Patients Derived Organoids
Cells 2020, 9(4), 832; https://doi.org/10.3390/cells9040832 (registering DOI) - 30 Mar 2020
Abstract
Cancer organoids are 3D phenotypic cultures that can be established from resected or biopsy tumour samples and can be grown as mini tumours in the dish. Flourishing evidence supports the feasibility of patient derived organoids (PDO) from a number of solid tumours. Evidence [...] Read more.
Cancer organoids are 3D phenotypic cultures that can be established from resected or biopsy tumour samples and can be grown as mini tumours in the dish. Flourishing evidence supports the feasibility of patient derived organoids (PDO) from a number of solid tumours. Evidence for cholangiocarcinoma (CCA) PDO is still sparse but growing. CCA PDO lines have been established from resected early stage disease, advanced cancers and highly chemorefractory tumours. Cancer PDO was shown to recapitulate the 3D morphology, genomic landscape and transcriptomic profile of the source counterpart. They proved to be a valued model for drug discovery and sensitivity testing, and they showed to mimic the drug response observed in vivo in the patients. However, PDO lack representation of the intratumour heterogeneity and the tumour-stroma interaction. The efficiency rate of CCA PDO within the three different subtypes, intrahepatic, perihilar and distal, is still to be explored. In this manuscript we will review evidence for CCA PDO highlighting advantages and limitations of this novel disease model. Full article
Open AccessFeature PaperArticle
A Simple Iron-Catalyst for Alkenylation of Ketones Using Primary Alcohols
Molecules 2020, 25(7), 1590; https://doi.org/10.3390/molecules25071590 (registering DOI) - 30 Mar 2020
Abstract
Herein, we developed a simple iron-catalyzed system for the α-alkenylation of ketones using primary alcohols. Such acceptor-less dehydrogenative coupling (ADC) of alcohols resulted in the synthesis of a series of important α,β-unsaturated functionalized ketones, having aryl, heteroaryl, alkyl, nitro, nitrile and trifluoro-methyl, as [...] Read more.
Herein, we developed a simple iron-catalyzed system for the α-alkenylation of ketones using primary alcohols. Such acceptor-less dehydrogenative coupling (ADC) of alcohols resulted in the synthesis of a series of important α,β-unsaturated functionalized ketones, having aryl, heteroaryl, alkyl, nitro, nitrile and trifluoro-methyl, as well as halogen moieties, with excellent yields and selectivity. Initial mechanistic studies, including deuterium labeling experiments, determination of rate and order of the reaction, and quantitative determination of H2 gas, were performed. The overall transformations produce water and dihydrogen as byproducts. Full article
(This article belongs to the Special Issue Recent Advances in Iron Catalysis)
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Open AccessFeature PaperArticle
Ultra-Compact Reconfigurable Band Reject UWB MIMO Antenna with Four Radiators
Electronics 2020, 9(4), 584; https://doi.org/10.3390/electronics9040584 (registering DOI) - 30 Mar 2020
Abstract
A compact reconfigurable UWB MIMO antenna with four radiators that accomplish on-demand band rejection from 4.9 to 6.3 GHz is presented. An LC stub is connected to the ground plane by activating the PIN diode for each radiator. Two radiators are placed perpendicular [...] Read more.
A compact reconfigurable UWB MIMO antenna with four radiators that accomplish on-demand band rejection from 4.9 to 6.3 GHz is presented. An LC stub is connected to the ground plane by activating the PIN diode for each radiator. Two radiators are placed perpendicular to each other to exploit the polarization diversity on a compact 25 × 50 mm 2 FR4 laminate. Two additional radiators are then fixed obliquely on the same laminate (without increasing size) in angular configuration at ±45 perpendicular to the first two planar radiators still exploiting polarization diversity. The design is validated by prototyping and comparing the results with the simulated ones. On demand band rejection through the use of PIN diodes, wide impedance matching (2–12 GHz), high isolation amongst the radiators, compactness achieved by angular placement of the radiators, low gain variation over the entire bandwidth, band rejection control achieved by adjusting the gap between stub and ground plane, and low TARC values makes the proposed design very suitable for commercial handheld devices (i.e., Huawei E5785 and Netgear 815S housings). The proposed configuration of the UWB MIMO radiators has been investigated first time as per authors’ knowledge. Full article
(This article belongs to the Special Issue Reconfigurable Antennas)
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Open AccessArticle
Effect of Boron Doping on Diamond Film and Electrochemical Properties of BDD According to Thickness and Morphology
Coatings 2020, 10(4), 331; https://doi.org/10.3390/coatings10040331 (registering DOI) - 30 Mar 2020
Abstract
Diamond coating using hot-filament chemical vapor deposition (HFCVD) is now widely used in many fields. The quality of the diamond film and many factors determine the success of the coating, such as temperature, time, and pressure during coating. The purpose of this study [...] Read more.
Diamond coating using hot-filament chemical vapor deposition (HFCVD) is now widely used in many fields. The quality of the diamond film and many factors determine the success of the coating, such as temperature, time, and pressure during coating. The purpose of this study was to produce coated boron-doped diamond (BDD) films by doping boron in the diamond film and to assess them through comparative analysis with foreign acid BDD, which is widely used as a water-treatment electrode in the present industry. The bending of the titanium substrate due to the high temperature during the diamond deposition was avoided by adding an intermediate layer with a columnar structure to niobium film. The filament temperature and pressure were determined through preliminary experiments, and BDD films were coated. The BDD film deposition rate was confirmed to be 100 nm/h, and the potential window increased with increasing thickness. The electrochemical activation and catalytic performance were confirmed according to the surface characteristics. Although the high deposition rate of the BDD coating is also an important factor, it was confirmed that conducting coating so that amorphous carbonization does not occur by controlling the temperature during coating can improve the electrochemical properties of BDD film. Full article
Open AccessArticle
An Easy-To-Use Survival Score Compared to Existing Tools for Older Patients with Cerebral Metastases from Colorectal Cancer
Cancers 2020, 12(4), 833; https://doi.org/10.3390/cancers12040833 (registering DOI) - 30 Mar 2020
Abstract
An easy-to-use survival score was developed specifically for older patients with cerebral metastases from colorectal cancer, and was compared to existing tools regarding the accuracy of identifying patients who die in ≤6 months and those who survive for ≥6 months. The new score [...] Read more.
An easy-to-use survival score was developed specifically for older patients with cerebral metastases from colorectal cancer, and was compared to existing tools regarding the accuracy of identifying patients who die in ≤6 months and those who survive for ≥6 months. The new score was built from 57 patients receiving whole-brain irradiation. It included three groups identified from 6-month survival rates based on two independent predictors (performance status and absence/presence of non-cerebral metastases), with 6-month survival rates of 0% (0 points), 26% (1 point), and 75% (2 points), respectively. This score was compared to diagnosis-specific scores, namely the diagnosis-specific graded prognostic assessment (DS-GPA), the Dziggel-Score and the WBRT-30-CRC (whole-brain radiotherapy with 30 Gy in 10 fractions for cerebral metastases from colorectal cancer) score and to a non-diagnosis-specific score for older persons (Evers-Score). Positive predictive values were 100% (new score), 87% (DS-GPA), 86% (Dziggel-Score), 91% (WBRT-30-CRC), and 100% (Evers-Score), respectively, for patients dying ≤6 months, and 75%, 33%, 75%, 60%, and 45%, respectively, for survivors ≥6 months. Of the five tools, the new score and the Evers-Score were most precise in identifying patients dying ≤6 months. The new score and the Dziggel-Scores were best at identifying patients surviving ≥6 months. When combining the results, the new score appeared preferable to the existing tools. The score appears not necessary for patients with additional liver metastases, since their 6-month survival rate was 0%. Full article
(This article belongs to the Special Issue Metastatic Colorectal Cancer)
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Open AccessArticle
Scaffold Hopping in Discovery of HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors: From CH(CN)-DABOs to CH(CN)-DAPYs
Molecules 2020, 25(7), 1581; https://doi.org/10.3390/molecules25071581 (registering DOI) - 30 Mar 2020
Abstract
Scaffold hopping is a frequently-used strategy in the development of non-nucleoside reverse transcriptase inhibitors. Herein, CH(CN)-DAPYs were designed by hopping the cyano-methylene linker of our previous published CH(CN)-DABOs onto the etravirine (ETR). Eighteen CH(CN)-DAPYs were synthesized and evaluated for their anti-HIV activity. Most [...] Read more.
Scaffold hopping is a frequently-used strategy in the development of non-nucleoside reverse transcriptase inhibitors. Herein, CH(CN)-DAPYs were designed by hopping the cyano-methylene linker of our previous published CH(CN)-DABOs onto the etravirine (ETR). Eighteen CH(CN)-DAPYs were synthesized and evaluated for their anti-HIV activity. Most compounds exhibited promising activity against wild-type (WT) HIV-1. Compounds B4 (EC50 = 6 nM) and B6 (EC50 = 8 nM) showed single-digit nanomolar potency against WT HIV-1. Moreover, these two compounds had EC50 values of 0.06 and 0.08 μM toward the K103N mutant, respectively, which were comparable to the reference efavirenz (EFV) (EC50 = 0.08 μM). The preliminary structure–activity relationship (SAR) indicated that introducing substitutions on C2 of the 4-cyanophenyl group could improve antiviral activity. Molecular docking predicted that the cyano-methylene linker was positioned into the hydrophobic cavity formed by Y181/Y188 and V179 residues. Full article
(This article belongs to the Special Issue Bioactive Molecules in Medicinal Chemistry)
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Open AccessArticle
An Effective and Efficient Enhanced Fixed Rank Smoothing Method for the Spatiotemporal Fusion of Multiple-Satellite Aerosol Optical Depth Products
Remote Sens. 2020, 12(7), 1102; https://doi.org/10.3390/rs12071102 (registering DOI) - 30 Mar 2020
Abstract
Current reported spatiotemporal solutions for fusing multisensor aerosol optical depth (AOD) products used to recover gaps either suffer from unacceptable accuracy levels, i.e., fixed rank smooth (FRS), or high time costs, i.e., Bayesian maximum entropy (BME). This problem is generally more serious when [...] Read more.
Current reported spatiotemporal solutions for fusing multisensor aerosol optical depth (AOD) products used to recover gaps either suffer from unacceptable accuracy levels, i.e., fixed rank smooth (FRS), or high time costs, i.e., Bayesian maximum entropy (BME). This problem is generally more serious when dealing with multiple AOD products in a long time series or over large geographic areas. This study proposes a new, effective, and efficient enhanced FRS method (FRS-EE) to fuse satellite AOD products with uncertainty constraints. AOD products used in the fusion experiment include Moderate Resolution Imaging SpectroRadiometer (MODIS) DB/DT_DB_Combined AOD and Multiangle Imaging SpectroRadiometer (MISR) AOD across mainland China from 2016 to 2017. Results show that the average completeness of original, initial FRS fused, and FRS-EE fused AODs with uncertainty constraints are 22.80%, 95.18%, and 65.84%, respectively. Although the correlation coefficient (R = 0.77), root mean square error (RMSE = 0.30), and mean bias (Bias = 0.023) of the initial FRS fused AODs are relatively lower than those of original AODs compared to Aerosol Robotic Network (AERONET) AOD records, the accuracy of FRS-EE fused AODs, which are R = 0.88, RMSE = 0.20, and Bias = 0.022, is obviously improved. More importantly, in regions with fully missing original AODs, the accuracy of FRS-EE fused AODs is close to that of original AODs in regions with valid retrievals. Meanwhile, the time cost of FRS-EE for AOD fusion was only 2.91 hours; obviously lower than the 30.46 months taken for BME. Full article
(This article belongs to the Special Issue Fusion of High-Level Remote Sensing Products)
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Open AccessArticle
FlexPro MD®, a Combination of Krill Oil, Astaxanthin and Hyaluronic Acid, Reduces Pain Behavior and Inhibits Inflammatory Response in Monosodium Iodoacetate-Induced Osteoarthritis in Rats
Nutrients 2020, 12(4), 956; https://doi.org/10.3390/nu12040956 (registering DOI) - 30 Mar 2020
Abstract
Osteoarthritis (OA) is a degenerative joint disease and a leading cause of adult disability. Since there is no cure for OA and no effective treatment to slow its progression, current pharmacologic treatments, such as analgesics and non-steroidal anti-inflammatory drugs (NSAIDs), only alleviate symptoms, [...] Read more.
Osteoarthritis (OA) is a degenerative joint disease and a leading cause of adult disability. Since there is no cure for OA and no effective treatment to slow its progression, current pharmacologic treatments, such as analgesics and non-steroidal anti-inflammatory drugs (NSAIDs), only alleviate symptoms, such as pain and inflammation, but do not inhibit the disease process. Moreover, chronic intake of these drugs may result in severe adverse effects. For these reasons, patients have turned to the use of various complementary and alternative approaches, including diverse dietary supplements and nutraceuticals, in an effort to improve symptoms and manage or slow disease progression. The present study was conducted to evaluate the anti-osteoarthritic effects of FlexPro MD® (a mixture of krill oil, astaxanthin, and hyaluronic acid; FP-MD) in a rat model of OA induced by monosodium iodoacetate (MIA). FP-MD significantly ameliorated joint pain and decreased the severity of articular cartilage destruction in rats that received oral supplementation for 7 days prior to MIA administration and for 21 days thereafter. Furthermore, FP-MD treatment significantly reduced serum levels of the articular cartilage degeneration biomarkers cartilage oligomeric matrix protein (COMP) and crosslinked C-telopeptide of type II collagen (CTX-II), and the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), as well as mRNA expression levels of inflammatory mediators, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and matrix-degrading enzymes, matrix metalloproteinase (MMP)-2 and MMP-9, in the knee joint tissue. Our findings suggest that FP-MD is a promising dietary supplement for reducing pain, minimizing cartilage damage, and improving functional status in OA, without the disadvantages of previous dietary supplements and medicinal agents, including multiple adverse effects. Full article
(This article belongs to the Special Issue New Research in Dietary Supplements and Healthy Foods)
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Open AccessReview
Vγ9Vδ2 T Cells: Can We Re-Purpose a Potent Anti-Infection Mechanism for Cancer Therapy?
Cells 2020, 9(4), 829; https://doi.org/10.3390/cells9040829 (registering DOI) - 30 Mar 2020
Abstract
Cancer therapies based on in vivo stimulation, or on adoptive T cell transfer of Vγ9Vδ2 T cells, have been tested in the past decades but have failed to provide consistent clinical efficacy. New, promising concepts such as γδ Chimeric Antigen Receptor (CAR) -T [...] Read more.
Cancer therapies based on in vivo stimulation, or on adoptive T cell transfer of Vγ9Vδ2 T cells, have been tested in the past decades but have failed to provide consistent clinical efficacy. New, promising concepts such as γδ Chimeric Antigen Receptor (CAR) -T cells and γδ T-cell engagers are currently under preclinical evaluation. Since the impact of factors, such as the relatively low abundance of γδ T cells within tumor tissue is still under investigation, it remains to be shown whether these effector T cells can provide significant efficacy against solid tumors. Here, we highlight key learnings from the natural role of Vγ9Vδ2 T cells in the elimination of host cells bearing intracellular bacterial agents and we translate these into the setting of tumor therapy. We discuss the availability and relevance of preclinical models as well as currently available tools and knowledge from a drug development perspective. Finally, we compare advantages and disadvantages of existing therapeutic concepts and propose a role for Vγ9Vδ2 T cells in immune-oncology next to Cluster of Differentiation (CD) 3 activating therapies. Full article
Open AccessReview
Diet, Lifestyle and Cardiovascular Diseases: Linking Pathophysiology to Cardioprotective Effects of Natural Bioactive Compounds
Int. J. Environ. Res. Public Health 2020, 17(7), 2326; https://doi.org/10.3390/ijerph17072326 (registering DOI) - 30 Mar 2020
Abstract
Heart and blood vessels disorders comprise one of the main causes of death worldwide. Pharmacologically active natural compounds have been used as a complementary therapy in cardiovascular disease around the world in a traditional way. Dietary, natural bioactive compounds, as well as healthy [...] Read more.
Heart and blood vessels disorders comprise one of the main causes of death worldwide. Pharmacologically active natural compounds have been used as a complementary therapy in cardiovascular disease around the world in a traditional way. Dietary, natural bioactive compounds, as well as healthy lifestyles, are considered to prevent coronary artery diseases. Pre-clinical and clinical studies reported that consumption of plant-food bioactive derivatives including polyphenolic compounds, peptides, oligosaccharides, vitamins, unsaturated fatty acids possess protective effects on cardiovascular diseases. This review aims to summarize the cardiovascular risk factors, pre-clinical studies and clinical trials related to cardioprotective properties of the plant-food-derived bioactive compounds. Molecular mechanisms by the natural bioactive compounds exert their cardiovascular protective properties have also been highlighted. Full article
(This article belongs to the Special Issue New insights in Prevention and Treatment of Cardiovascular Disease)
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Open AccessArticle
Settlement and Spreading of the Introduced Seaweed Caulacanthus okamurae (Rhodophyta) in the Mediterranean Sea
Diversity 2020, 12(4), 129; https://doi.org/10.3390/d12040129 (registering DOI) - 30 Mar 2020
Abstract
In this study, we report the first finding of the non-indigenous seaweed Caulacanthus okamurae (Rhodophyta) in the Ionian and Adriatic Seas (Mediterranean). Specimens were identified through molecular analyses based on the plastid ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) marker. The sequences obtained during this [...] Read more.
In this study, we report the first finding of the non-indigenous seaweed Caulacanthus okamurae (Rhodophyta) in the Ionian and Adriatic Seas (Mediterranean). Specimens were identified through molecular analyses based on the plastid ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) marker. The sequences obtained during this study represent the first molecular evidence of the presence of this taxon in the Mediterranean Sea. Stable populations have been detected in some areas of the Mar Piccolo of Taranto (Italy) and in the whole lagoon of Venice, forming dense patches of low turf that reach high biomasses. Turf-forming algae are common in the intertidal zones of tropical regions, but are rare in temperate ones. The particular environmental conditions of transitional water systems, such as the Mar Piccolo of Taranto and the Venice Lagoon, together with the water temperature increase observed in the last years could have favored the settlement and spread of this introduced species. Full article
(This article belongs to the Special Issue Biodiversity of Macroalgae)
Open AccessReview
Smart City and High-Tech Urban Interventions Targeting Human Health: An Equity-Focused Systematic Review
Int. J. Environ. Res. Public Health 2020, 17(7), 2325; https://doi.org/10.3390/ijerph17072325 (registering DOI) - 30 Mar 2020
Abstract
Urban infrastructure systems responsible for the provision of energy, transportation, shelter, and communication to populations are important determinants of health and health equity. The term “smart city” has been used synonymously with other terms, such as “digital city”, “sustainable city”, and “information city”, [...] Read more.
Urban infrastructure systems responsible for the provision of energy, transportation, shelter, and communication to populations are important determinants of health and health equity. The term “smart city” has been used synonymously with other terms, such as “digital city”, “sustainable city”, and “information city”, even though definitional distinctions exist between terms. In this review, we use “smart cities” as a catch-all term to refer to an emerging concept in urban governance practice and scholarship that has been increasingly applied to achieve public health aims. The objective of this systematic review was to document and analyze the inclusion of equity considerations and dimensions (i.e., a measurement, analytical, or dialectical focus on systematic disparities in health between groups) in smart city interventions aimed to improve human health and well-being. Systematic searches were carried out in the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Psychological Information Database (PsycINFO), the PubMed database from the National Center for Biotechnology Information, Elsevier’s database Scopus, and Web of Science, returning 3219 titles. Ultimately, 28 articles were retained, assessed, and coded for their inclusion of equity characteristics using the Cochrane PROGRESS-Plus tool (referring to (P) place of residence, (R) race, (O) occupation, (G) gender, (R) religion, (E) education, (S) socio-economic status (SES), and (S) social capital). The most frequently included equity considerations in smart city health interventions were place of residence, SES, social capital, and personal characteristics; conversely, occupation, gender or sex, religion, race, ethnicity, culture, language, and education characteristics were comparatively less featured in such interventions. Overall, it appears that most of intervention evaluations assessed in this review are still in the early testing phases, and thus did not include or feature robust evaluative designs or commercially available technologies Full article
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Open AccessArticle
Fine Fabrication and Optical Waveguide Characteristics of Hexagonal tris(8-hydroxyquinoline)aluminum(Ⅲ) (Alq3) Crystal
Crystals 2020, 10(4), 260; https://doi.org/10.3390/cryst10040260 (registering DOI) - 30 Mar 2020
Abstract
Herein, we reported on the precise growth and optical waveguide characteristics of hexagonal tris(8-hydroxyquinoline)aluminum(Ⅲ) (Alq3) micro-crystals (MCs). The hexagonal Alq3 MCs were prepared using surfactant-assisted assembly growth with the help of cetyltrimethylammoniumbromide (CTAB), in which the crystallization occurred as a [...] Read more.
Herein, we reported on the precise growth and optical waveguide characteristics of hexagonal tris(8-hydroxyquinoline)aluminum(Ⅲ) (Alq3) micro-crystals (MCs). The hexagonal Alq3 MCs were prepared using surfactant-assisted assembly growth with the help of cetyltrimethylammoniumbromide (CTAB), in which the crystallization occurred as a result of molecular assembly and packing. Also, we adjusted the molar ratio of Alq3 and CTAB for the control degree of crystallization. The formation and structure of Alq3 MCs were investigated using field-emission scanning electron microscopy and X-ray diffraction pattern experiments, respectively. The solid-state laser confocal microscope-photoluminescence spectra and charge-coupled device images for the Alq3 MCs were measured to study the luminescence efficiency and colors, respectively. The optical waveguide performance of the hexagonal Alq3 MCs was measured for each side direction. According to our results, crystalline Alq3 micro-crystals are promising materials for application to the development of optical communication devices. Full article
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Open AccessArticle
Selection of Policy Instruments on Integrated Care in China: Based on Documents Content Analysis
Int. J. Environ. Res. Public Health 2020, 17(7), 2327; https://doi.org/10.3390/ijerph17072327 (registering DOI) - 30 Mar 2020
Abstract
Facing the aggravating trend of an aging population and a fragmented medical service delivery system, the Chinese Central Government has introduced a series of policies to promote the development of integrated care against the background of the “Healthy China Strategy”. The achievement of [...] Read more.
Facing the aggravating trend of an aging population and a fragmented medical service delivery system, the Chinese Central Government has introduced a series of policies to promote the development of integrated care against the background of the “Healthy China Strategy”. The achievement of integrated care depends on the choice of policy instruments. However, few studies have focused on how policy instruments promote the practice of integrated care in China. This article aims to obtain a deeper understanding of the use of policy instruments in the development of integrated care in China. Policy documents are the carriers of policy instruments. National-level integrated care policy documents from 2009 to 2019 were selected. Using the qualitative document analysis method, this paper conducts an analysis of integrated care policy instruments. In order to comprehensively view the integrated care policy instruments, a three-dimensional analytical framework consisting of the policy instruments dimension, stakeholders dimension, and health service supply chains dimension is proposed. The results are as follows. (1) From the perspective of policy instruments, the integrated care policy has adopted supply-side policy instruments, demand-side policy instruments, and environmental policy instruments. Among the three types of policy instruments, environmental policy instruments are used most frequently, supply-side policies are preferred, while demand-side policy instruments are relatively inadequate. (2) As for the stakeholders dimension, the central policy instruments focus on the health service providers, while less attention is paid to the health service demanders. (3) In terms of health service supply chains, the number of policy instruments used in the prevention stage is the highest, followed by the treatment stage, whereas less attention paid to the rehabilitation stage. Finally, suggestions were made for the development of integrated care by better perfecting policy instruments. Full article
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Open AccessFeature PaperArticle
Electrocatalytic Assisted Performance Enhancement for the Na-S Battery in Nitrogen-Doped Carbon Nanospheres Loaded with Fe
Molecules 2020, 25(7), 1585; https://doi.org/10.3390/molecules25071585 (registering DOI) - 30 Mar 2020
Abstract
Room temperature sodium-sulfur batteries have been considered to be potential candidates for future energy storage devices because of their low cost, abundance, and high performance. The sluggish sulfur reaction and the “shuttle effect” are among the main problems that hinder the commercial utilization [...] Read more.
Room temperature sodium-sulfur batteries have been considered to be potential candidates for future energy storage devices because of their low cost, abundance, and high performance. The sluggish sulfur reaction and the “shuttle effect” are among the main problems that hinder the commercial utilization of room temperature sodium-sulfur batteries. In this study, the performance of a hybrid that was based on nitrogen (N)-doped carbon nanospheres loaded with a meagre amount of Fe ions (0.14 at.%) was investigated in the sodium-sulfur battery. The Fe ions accelerated the conversion of polysulfides and provided a stronger interaction with soluble polysulfides. The Fe-carbon nanospheres hybrid delivered a reversible capacity of 359 mAh·g−1 at a current density of 0.1 A·g−1 and retained a capacity of 180 mAh·g−1 at 1 A·g−1, after 200 cycles. These results, combined with the excellent rate performance, suggest that Fe ions, even at low loading, are able to improve the electrocatalytic effect of carbon nanostructures significantly. In addition to Na-S batteries, the new hybrid is anticipated to be a strong candidate for other energy storage and conversion applications such as other metal-sulfur batteries and metal-air batteries. Full article
(This article belongs to the Special Issue Advances in Electrochemical Energy Storage Devices)
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Open AccessArticle
Dynamical Networks Modelling Applied to Low Voltage Lines with Nonlinear Filters
Appl. Syst. Innov. 2020, 3(2), 18; https://doi.org/10.3390/asi3020018 (registering DOI) - 30 Mar 2020
Abstract
The nonlinear dynamical behaviour of a network that is submitted to disturbances is the starting point of this work, where we consider a low voltage line (the network) with nonlinear varistor filters responding, dynamically, to those disturbances. Network models consider static measurements, and [...] Read more.
The nonlinear dynamical behaviour of a network that is submitted to disturbances is the starting point of this work, where we consider a low voltage line (the network) with nonlinear varistor filters responding, dynamically, to those disturbances. Network models consider static measurements, and here we develop an iterative model to deal with dynamical measurements. We begin with the one-dimensional communication line model using reflected and incident signals, which are dependent on the node parameters, proceeding a time-step computation. Each node is a space representation that consolidates parameters for a specific vertex and its edges. Nonlinear functions are applied within the node and will contribute to the general process running on the structure. The idea of a structure and its related processes leads to a new concept of sustainability and system robustness. This concludes the work, along with several experimental and simulation results, with direct advantages to electromagnetic interference control and mitigation. Full article
(This article belongs to the Special Issue Non-linear Devices, Systems, Networks and Their Applications)
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