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Article
Combined Developmental Toxicity of the Pesticides Difenoconazole and Dimethomorph on Embryonic Zebrafish
by , , , , , , , and
Toxins 2021, 13(12), 854; https://doi.org/10.3390/toxins13120854 (registering DOI) - 01 Dec 2021
Abstract
Difenoconazole (DIF) and dimethomorph (DIM) are widely used pesticides frequently detected together in environmental samples, so the deleterious effects of combined exposure warrant detailed examination. In this study, the individual and combined effects of DIM and DIF on conventional developmental parameters (hatching rate, [...] Read more.
Difenoconazole (DIF) and dimethomorph (DIM) are widely used pesticides frequently detected together in environmental samples, so the deleterious effects of combined exposure warrant detailed examination. In this study, the individual and combined effects of DIM and DIF on conventional developmental parameters (hatching rate, deformity rate, lethality) and gene expression were measured in embryonic zebrafish. Both DIF and DIM interfered with normal zebrafish embryo development, and the most sensitive toxicity index for both was 96 h post-fertilization (hpf) deformity rate (BMDL10 values of 0.30 and 1.10 mg/L, respectively). The combination of DIF and DIM had mainly synergistic deleterious effects on 96 hpf deformity and mortality rates. Transcriptome analysis showed that these compounds markedly downregulated expression of mcm family genes, cdk1, and cdc20, thereby potentially disrupting DNA replication and cell cycle progression. Enhanced surveillance for this pesticide combination is recommended as simultaneous environmental exposure may be substantially more harmful than exposure to either compound alone. Full article
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Review
The Intricate Web of Fatigue in Women
by
Women 2021, 1(4), 267-279; https://doi.org/10.3390/women1040023 (registering DOI) - 01 Dec 2021
Abstract
The modern woman has taken her rightful place in society as a worker, a caregiver, a mother, and a world citizen. However, along with the privileges of these roles comes the great cost of stress and resultant exhaustion and fatigue. Psychosocial, physical, cultural, [...] Read more.
The modern woman has taken her rightful place in society as a worker, a caregiver, a mother, and a world citizen. However, along with the privileges of these roles comes the great cost of stress and resultant exhaustion and fatigue. Psychosocial, physical, cultural, and disease-related realms of stress act as strands of a web that serve to bind and hinder women with chronic stress. New areas of research, such as exercise intervention, improved social programs (e.g., childcare), and supplementation are constantly evaluated for effectiveness alongside traditional remedies such as exercise. This review will highlight some of the key issues regarding stress in women and explore reports of new treatment modalities in light of the specific requirements of the modern woman. Full article
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Article
Feasibility of Elder-Friendly Food Applications of Sacha Inchi According to Cooking Method: Focusing on Analysis of Antioxidative Activity and Brain Neuron Cell Viability
by and
Foods 2021, 10(12), 2948; https://doi.org/10.3390/foods10122948 (registering DOI) - 01 Dec 2021
Abstract
One of the objectives of this study was to determine the effect of the cooking method on the antioxidant activity of Sacha inchi (Plukenetia volubilis). This work was focused on the importance of performing proper cooking for studying Sacha inchi. The [...] Read more.
One of the objectives of this study was to determine the effect of the cooking method on the antioxidant activity of Sacha inchi (Plukenetia volubilis). This work was focused on the importance of performing proper cooking for studying Sacha inchi. The result of this study sheds light on preventing nutritional loss with appropriate cooking methods. Three types of cooking processes were selected: uncooked, roasted at 160 °C for 6 min, boiled at 100 °C for 13 min. The results of the present study indicated that roasted Sacha inchi is distinguishable for its high content of antioxidants (total polyphenol content 485.50 μM, total flavonoid content 0.02 μg/mL, DPPH free radical scavenging activity 33.05%, ferric reducing ability 0.19 μM). The results of the present study also indicated that Sacha inchi uniquely promotes HT22 cell viability. With roasted Sacha inchi treatment, HT22 hippocampal neuronal cell showed a significantly increased number of growth (p < 0.001). Results also suggest that the development of tenderized Sacha inchi could help the elderly consumers achieve their target antioxidant provision in smaller portion sizes, thus curtailing the peril of sarcopenia. The mousse type of elderly food may also change the taste of many other nut consumers as they may opt to start selling and consuming Sacha inchi. It could be in the Sacha inchi industry’s best interest to make certain all of the population’s textural favors are catered. Full article
(This article belongs to the Section Nutraceuticals and Functional Foods)
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Article
Association of Feed Efficiency, Feeding Rate, and Behaviour with the Milk Performance of Dairy Cows
by , , , , , , and
Dairy 2021, 2(4), 684-694; https://doi.org/10.3390/dairy2040053 (registering DOI) - 01 Dec 2021
Abstract
Identification of the associations of cow feed efficiency with feeding behaviour and milk production is important for supporting recommendations of strategies that optimise milk yield. The objective of this study was to identify associations between measures of feed efficiency, feed intake, feeding rate, [...] Read more.
Identification of the associations of cow feed efficiency with feeding behaviour and milk production is important for supporting recommendations of strategies that optimise milk yield. The objective of this study was to identify associations between measures of feed efficiency, feed intake, feeding rate, rumination time, feeding time, and milk production using data collected from 26 dairy cows during a 3 month period in 2018. Cows averaged (mean ± standard deviation) 2.2 ± 1.7 lactations, 128 ± 40 days in milk, 27.5 ± 5.5 kg/day milk, 1.95 ± 0.69 kg feed/1 kg milk—the measure used to express feed conversion ratio (FCR), 575 ± 72 min/day rumination time, and 264 ± 67 min/day feeding time during the observation period. The coefficient of variation for rumination time (min/d) was 12.5%. A mixed linear model was selected for analyses. The most feed inefficient cows with the highest FCR (≥2.6 kg feed/1 kg milk) showed the lowest milk yield (24.8 kg/day), highest feed intake (78.8 kg), highest feeding rate (0.26 kg/min) and BCS (3.35 point). However, the relative milk yield (milk yield per 100 kg of body weight) was the highest (4.01 kg/day) in the most efficient group with the lowest FCR (≤1.4 kg feed/1 kg milk). Our study showed that the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk) had the highest rumination time (597 min/day; p < 0.05), feeding time (298 min/day; p < 0.05), rumination/activity ratio (4.39; p < 0.05) and rumination/feeding ratio (2.04; p < 0.05). Less active cows (activity time 164 min/day; p < 0.05) were the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk). The behavioural differences observed in this study provide new insight into the association of feed behaviour and feed efficiency with milk performance. Incorporating feeding behaviour into the dry matter intake model can improve its accuracy in the future and benefit breeding programmes. Full article
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Article
Numerical and Non-Destructive Analysis of an Aluminum-CFRP Hybrid 3D Structure
by , , , and
Metals 2021, 11(12), 1938; https://doi.org/10.3390/met11121938 - 30 Nov 2021
Abstract
Advanced materials are widely used in many industries. They play an important role especially in the aeronautic and automotive sectors where weight reduction is required in order to reduce fuel consumption. Composite materials have a high strength to weight ratio and are applied [...] Read more.
Advanced materials are widely used in many industries. They play an important role especially in the aeronautic and automotive sectors where weight reduction is required in order to reduce fuel consumption. Composite materials have a high strength to weight ratio and are applied in airplane construction. Nevertheless, sometimes it is not viable to replace all metal parts by composite ones due to the cost factor. In this sense, hybrid structures are highly welcome. In order to ensure the safety of these hybrid components during their entire life cycle, non-destructive testing evaluation (NDT&E) methods are used and sometimes they are the only option. In this study, we use infrared thermography (IRT) to inspect an aluminum-composite hybrid structure with a 3D shape. The sample has a composite part with a small metal inlay (EN AW-6082) overmolded with a thermoplastic layer. The inlay is bended to reach the desired 3D geometry. This sample was design to be used for the connection between an A- or B-pillar and a car roof made of carbon fiber reinforced polymer (CFRP). A dual-band infrared camera is used in order to capture images in two different spectral ranges. In addition, two data processing techniques for infrared images are applied to enhance the images: principal component thermography (PCT) and partial least squares thermography (PLST). Then, a signal-to-noise ratio analysis is performed with three randomly chosen previous known defects to assess the quality of the images and detected defects. Results showed that principal component thermography has a slight advantage over partial least squares thermography in our specific experiments. Specifically, for the long-wave infrared band, PCT presented, among the defects analyzed, PCT presented a mean value 12.5% higher while the standard deviation was almost three times lower than PLST. In parallel to the non-detructive analysis, a numerical finite element model was formulated in ANSYS® to analyze the total deformations to which the metal-composite-hybrid structure is subjected during a possible use. Results obtained with the numerical model indicate that the interface region between composite and metal parts is where the highest degree of deformation occur, which indicates possible regions where defects and failures may occur in real use cases. Full article
(This article belongs to the Special Issue Characterization and Monitoring of Metal-CFRP-Hybrid Structures)
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Article
Effects of Anesthetic Technique on the Occurrence of Acute Kidney Injury after Spine Surgery: A Retrospective Cohort Study
by , , , and
J. Clin. Med. 2021, 10(23), 5653; https://doi.org/10.3390/jcm10235653 - 30 Nov 2021
Abstract
The effects of anesthetics on acute kidney injury (AKI) after spine surgery have not been evaluated fully. This study compared propofol-based total intravenous anesthesia (TIVA) and volatile anesthetics in the development of AKI after spine surgery. This retrospective study reviewed patients who underwent [...] Read more.
The effects of anesthetics on acute kidney injury (AKI) after spine surgery have not been evaluated fully. This study compared propofol-based total intravenous anesthesia (TIVA) and volatile anesthetics in the development of AKI after spine surgery. This retrospective study reviewed patients who underwent spine surgery between 2015 and 2019. A logistic regression analysis was performed to identify risk factors for AKI. Additionally, after propensity score matching, the incidence of AKI was compared between TIVA and volatile groups. Of the 4473 patients, 709 were excluded and 3764 were included in the logistic regression. After propensity score matching, 766 patients from each group were compared, and we found that the incidence of AKI was significantly lower in the TIVA group (1% vs. 4.2%, p < 0.001). In the multivariate logistic regression analysis, the risk factors for postoperative AKI were male sex (OR 1.85, 95% CI 1.18–3.06), hypertension (OR 2.48, 95% CI 1.56–3.94), anemia (OR 2.66, 95% CI 1.76–4.04), and volatile anesthetics (OR 4.69, 95% CI 2.24–9.84). Compared with volatile anesthetics, TIVA is associated with a reduced risk of AKI for patients who have undergone spine surgery. Full article
(This article belongs to the Section Anesthesiology)
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Review
The Effect of Organoselenium Compounds on Histone Deacetylase Inhibition and Their Potential for Cancer Therapy
by , , , and
Int. J. Mol. Sci. 2021, 22(23), 12952; https://doi.org/10.3390/ijms222312952 - 30 Nov 2021
Abstract
Genetic and epigenetic changes alter gene expression, contributing to cancer. Epigenetic changes in cancer arise from alterations in DNA and histone modifications that lead to tumour suppressor gene silencing and the activation of oncogenes. The acetylation status of histones and non-histone proteins are [...] Read more.
Genetic and epigenetic changes alter gene expression, contributing to cancer. Epigenetic changes in cancer arise from alterations in DNA and histone modifications that lead to tumour suppressor gene silencing and the activation of oncogenes. The acetylation status of histones and non-histone proteins are determined by the histone deacetylases and histone acetyltransferases that control gene transcription. Organoselenium compounds have become promising contenders in cancer therapeutics. Apart from their anti-oxidative effects, several natural and synthetic organoselenium compounds and metabolites act as histone deacetylase inhibitors, which influence the acetylation status of histones and non-histone proteins, altering gene transcription. This review aims to summarise the effect of natural and synthetic organoselenium compounds on histone and non-histone protein acetylation/deacetylation in cancer therapy. Full article
(This article belongs to the Section Molecular Oncology)
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Article
Modeling the Effect of Alternative Cementitious Binders in Ultra-High-Performance Concrete
by , , , and
Materials 2021, 14(23), 7333; https://doi.org/10.3390/ma14237333 - 30 Nov 2021
Abstract
The use of alternative cementitious binders is necessary for producing sustainable concrete. Herein, we study the effect of using alternative cementitious binders in ultra-high-performance concrete (UPHC) by calculating the phase assemblages of UHPC in which Portland cement is replaced with calcium aluminate cement, [...] Read more.
The use of alternative cementitious binders is necessary for producing sustainable concrete. Herein, we study the effect of using alternative cementitious binders in ultra-high-performance concrete (UPHC) by calculating the phase assemblages of UHPC in which Portland cement is replaced with calcium aluminate cement, calcium sulfoaluminate cement, metakaolin or blast furnace slag. The calculation result shows that replacing Portland cement with calcium aluminate cement or calcium sulfoaluminate cement reduces the volume of C-S-H but increases the overall solid volume due to the formation of other phases, such as strätlingite or ettringite. The modeling result predicts that using calcium aluminate cement or calcium sulfoaluminate cement may require more water than it would for plain UHPC, while a similar or lower amount of water is needed for chemical reactions when using blast furnace slag or metakaolin. Full article
(This article belongs to the Special Issue Sustainable Construction Materials: From Paste to Concrete)
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Article
Evolution of Thermophilic Microbial Communities from a Deep-Sea Hydrothermal Chimney under Electrolithoautotrophic Conditions with Nitrate
by , , , , , , and
Microorganisms 2021, 9(12), 2475; https://doi.org/10.3390/microorganisms9122475 - 30 Nov 2021
Abstract
Recent studies have shown the presence of an abiotic electrical current across the walls of deep-sea hydrothermal chimneys, allowing the growth of electroautotrophic microbial communities. To understand the role of the different phylogenetic groups and metabolisms involved, this study focused on electrotrophic enrichment [...] Read more.
Recent studies have shown the presence of an abiotic electrical current across the walls of deep-sea hydrothermal chimneys, allowing the growth of electroautotrophic microbial communities. To understand the role of the different phylogenetic groups and metabolisms involved, this study focused on electrotrophic enrichment with nitrate as electron acceptor. The biofilm density, community composition, production of organic compounds, and electrical consumption were monitored by FISH confocal microscopy, qPCR, metabarcoding, NMR, and potentiostat measurements. A statistical analysis by PCA showed the correlation between the different parameters (qPCR, organic compounds, and electron acceptors) in three distinct temporal phases. In our conditions, the Archaeoglobales have been shown to play a key role in the development of the community as the first colonizers on the cathode and the first producers of organic compounds, which are then used as an organic source by heterotrophs. Finally, through subcultures of the community, we showed the development of a greater biodiversity over time. This observed phenomenon could explain the biodiversity development in hydrothermal contexts, where energy sources are transient and unstable. Full article
(This article belongs to the Special Issue Diversity of Extremophiles in Hydrothermal Environments)
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Article
Targeting CAMKK2 and SOC Channels as a Novel Therapeutic Approach for Sensitizing Acute Promyelocytic Leukemia Cells to All-Trans Retinoic Acid
by , , , , , , , , and
Cells 2021, 10(12), 3364; https://doi.org/10.3390/cells10123364 - 30 Nov 2021
Abstract
Calcium ions (Ca2+) play important and diverse roles in the regulation of autophagy, cell death and differentiation. Here, we investigated the impact of Ca2+ in regulating acute promyelocytic leukemia (APL) cell fate in response to the anti-cancer agent all-trans retinoic [...] Read more.
Calcium ions (Ca2+) play important and diverse roles in the regulation of autophagy, cell death and differentiation. Here, we investigated the impact of Ca2+ in regulating acute promyelocytic leukemia (APL) cell fate in response to the anti-cancer agent all-trans retinoic acid (ATRA). We observed that ATRA promotes calcium entry through store-operated calcium (SOC) channels into acute promyelocytic leukemia (APL) cells. This response is associated with changes in the expression profiles of ORAI1 and STIM1, two proteins involved in SOC channels activation, as well as with a significant upregulation of several key proteins associated to calcium signaling. Moreover, ATRA treatment of APL cells led to a significant activation of calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) and its downstream effector AMP-activated protein kinase (AMPK), linking Ca2+ signaling to autophagy. Pharmacological inhibition of SOC channels and CAMKK2 enhanced ATRA-induced cell differentiation and death. Altogether, our results unravel an ATRA-elicited signaling pathway that involves SOC channels/CAMKK2 activation, induction of autophagy, inhibition of cellular differentiation and suppression of cell death. We suggest that SOC channels and CAMKK2 may constitute novel drug targets for potentiating the anti-cancer effect of ATRA in APL patients. Full article
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Review
Mid-Diastolic Events (L Events): A Critical Review
by , , , , , , , , , , , and
J. Clin. Med. 2021, 10(23), 5654; https://doi.org/10.3390/jcm10235654 - 30 Nov 2021
Abstract
Mid-diastolic events (L events) include three phenomena appreciable on echocardiography occurring during diastasis: mid-diastolic transmitral flow velocity (L wave), mid-diastolic mitral valve motion (L motion), and mid-diastolic mitral annular velocity (L’ wave). L wave is a known marker of advanced diastolic dysfunction in [...] Read more.
Mid-diastolic events (L events) include three phenomena appreciable on echocardiography occurring during diastasis: mid-diastolic transmitral flow velocity (L wave), mid-diastolic mitral valve motion (L motion), and mid-diastolic mitral annular velocity (L’ wave). L wave is a known marker of advanced diastolic dysfunction in different pathological clinical settings such as left ventricle and atrial remodeling, overloaded states, and cardiomyopathies. Patients with L events have poor outcomes with a higher risk of developing heart failure symptoms and arrhythmic complications, including sudden cardiac death. The exact mechanism underlying the genesis of mid-diastolic events is not fully understood, just as the significance of these events in healthy young people or their presence at the tricuspid valve level. We also report an explicative case of a patient with L events studied using speckle tracking imaging of the left atrium and ventricle at the same reference heartbeat supporting the hypothesis of a post-early diastolic relaxation or a “two-step” ventricular relaxation for L wave genesis. Our paper seeks to extend knowledge about the pathophysiological mechanisms on mid-diastolic events and summarizes the current knowledge. Full article
(This article belongs to the Section Cardiology)
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Article
The Analysis of Erosive Wear Resistance of WC-Co Carbides Obtained by Spark Plasma Sintering Method
by , , , , , , and
Materials 2021, 14(23), 7326; https://doi.org/10.3390/ma14237326 - 30 Nov 2021
Abstract
WC-Co (tungsten carbide-cobalt) composites are widely used in industry, wear-resistant parts, and cutting tools. As successful tool materials, WC-Co carbides are widely applied in metal cutting, wear applications, chipless forming, stoneworking, wood, and plastic working. These materials are exposed to severe solid particle [...] Read more.
WC-Co (tungsten carbide-cobalt) composites are widely used in industry, wear-resistant parts, and cutting tools. As successful tool materials, WC-Co carbides are widely applied in metal cutting, wear applications, chipless forming, stoneworking, wood, and plastic working. These materials are exposed to severe solid particle erosion by sand particles, such as in the wood industry. During the production of furniture with HDF (High Density Fibreboard), MDF (Medium Density Fibreboard), or OSB (Oriented Strand Board), there are observed problems with tool erosion. Contamination, mainly of the HDF by sand, is quite often, which is why all tools used for the machining of such materials are exposed to erosion by sand particles. Although many studies have been performed on the erosion of various metals, and erosion models exist to predict their erosion behavior, the issue is still relevant. The aim of the study was to determine the effect of grain size (submicron, ultrafine) and the manufacturing technology (SPS—Spark Plasma Sintering, conventional) used on the erosive properties of WC-Co sintered carbides. Sinters produced by the SPS method with different sizes of WC grains and commercial samples were used for the tests. Ten two-hour cycles were carried out under medium conditions of quartz sand and quartz sand with 10% SiC added. Used samples were characterised using scanning electron microscopy (SEM) and roughness was determined. Furthermore, erosion studies allowed individuating a wear mechanism as well as the possibility to foresee cutting performance in prospective application. Full article
(This article belongs to the Special Issue Modification of Materials with Ion/Plasma Beams)
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Article
Heavy Metal in Rice and Vegetable and Human Exposure near a Large Pb/Zn Smelter in Central China
by , , , , , , , , and
Int. J. Environ. Res. Public Health 2021, 18(23), 12631; https://doi.org/10.3390/ijerph182312631 - 30 Nov 2021
Abstract
Non-ferrous metal smelting is a significant source of anthropogenic heavy metal emission and has led to severe environmental pollution that ultimately threatens the health of local residents. In this study, we determined concentrations of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), [...] Read more.
Non-ferrous metal smelting is a significant source of anthropogenic heavy metal emission and has led to severe environmental pollution that ultimately threatens the health of local residents. In this study, we determined concentrations of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), as well as Pb isotopic compositions in rice, vegetables and human hair in areas surrounding the Zhuzhou Pb/Zn smelter in Hunan, China and we assessed the health risks associated with rice and vegetable consumption for local residents. Results showed that rice and vegetable samples were significantly contaminated by Cd and Pb. Age and source of rice were important factors for the enrichment of heavy metal concentrations in human hair. The ratios of Pb isotopes in human hair (1.164–1.170 for 206Pb/207Pb and 2.102–2.110 for208Pb/206Pb) were comparable to those in rice (1.162–1.172 for 206Pb/207Pb and 2.098–2.114 for208Pb/206Pb) and were slightly lower than those in vegetables (1.168–1.172 for 206Pb/207Pb and 2.109–2.111 for208Pb/206Pb), indicating that Pb in human hair mainly originated from food ingestion. A non-carcinogenic risk assessment showed that Cd exposure was the dominant health risk for local residents. This study suggested that crops planted surrounding the smelter were seriously contaminated with Cd and human exposure was related to dietary intake. Full article
(This article belongs to the Section Environmental Earth Science and Medical Geology)
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Review
Ecological Entomology: How Is Gibson’s Framework Useful?
by , and
Insects 2021, 12(12), 1075; https://doi.org/10.3390/insects12121075 - 30 Nov 2021
Abstract
To date, numerous studies have demonstrated the fundamental role played by optic flow in the control of goal-directed displacement tasks in insects. Optic flow was first introduced by Gibson as part of their ecological approach to perception and action. While this theoretical approach [...] Read more.
To date, numerous studies have demonstrated the fundamental role played by optic flow in the control of goal-directed displacement tasks in insects. Optic flow was first introduced by Gibson as part of their ecological approach to perception and action. While this theoretical approach (as a whole) has been demonstrated to be particularly suitable for the study of goal-directed displacements in humans, its usefulness in carrying out entomological field studies remains to be established. In this review we would like to demonstrate that the ecological approach to perception and action could be relevant for the entomologist community in their future investigations. This approach could provide a conceptual and methodological framework for the community in order to: (i) take a critical look at the research carried out to date, (ii) develop rigorous and innovative experimental protocols, and (iii) define scientific issues that push the boundaries of the current scientific field. After a concise literature review about the perceptual control of displacement in insects, we will present the framework proposed by Gibson and suggest its added value for carrying out research in the field of behavioral ecology in insects. Full article
(This article belongs to the Collection Insect Senses: From Perception to Cognition)
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Article
The Development of Frequency Tripler Based on Six-Anode Schottky Varactors
by , , and
Micromachines 2021, 12(12), 1490; https://doi.org/10.3390/mi12121490 - 30 Nov 2021
Abstract
The development of a millimeter-wave unbalanced frequency tripler based on the nonlinear characteristics of planar Schottky varactors is presented. The entire module is designed by hybrid integration. A frequency multiplier circuit model was established to reflect the influence of diode parameters and the [...] Read more.
The development of a millimeter-wave unbalanced frequency tripler based on the nonlinear characteristics of planar Schottky varactors is presented. The entire module is designed by hybrid integration. A frequency multiplier circuit model was established to reflect the influence of diode parameters and the impedance matching on the multiplier in different frequency bands. The effect of junction imbalance on the output power of the frequency multiplier was investigated and the multiplier was improved based on the basic design. The addition of a cut microstrip stub in the improved diode unit reduced the impact of a power imbalance on frequency multiplier performance. The characteristics of the multiplier circuit were analyzed by the full-wave electromagnetic simulation of the three-dimensional structure and the harmonic balance simulation of the circuit. Test results showed that the peak output power of the improved frequency tripler was 12.6 mW at 277 GHz with an input power of 200 mW, an effective 12% improvement over the basic design. Full article
(This article belongs to the Special Issue Passive and Active THz Components)
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Article
Characteristics of Thermal Parameters and Some Physical Properties of Mineral Eutectic Type: Petalite–Alkali Feldspars
by
Materials 2021, 14(23), 7321; https://doi.org/10.3390/ma14237321 - 30 Nov 2021
Abstract
The aim of the research was to check whether the system of three fluxes based on lithium aluminium silicate and alkali feldspars has a eutectic point, i.e., with the lowest melting temperature. Lithium was introduced into the mixtures in the form of petalite, [...] Read more.
The aim of the research was to check whether the system of three fluxes based on lithium aluminium silicate and alkali feldspars has a eutectic point, i.e., with the lowest melting temperature. Lithium was introduced into the mixtures in the form of petalite, which occurs naturally in nature (Bikita Zimbabwe deposit). Using naturally occurring raw materials such as petalite, sodium feldspar, and potassium feldspar, an attempt was made to obtain eutectics with the lowest melting point to facilitate thermal processing of the mineral materials. In addition, the high-temperature viscosity of the mineral alloys and physical parameters such as density, linear shrinkage, and open porosity were studied. The study showed that in these systems, there is one three-component eutectic at 1345 °C, with the lowest viscosity of 1·105 Pas and the highest density of 2.34g/cm3, with a weight content of petalite 20%, sodium feldspar 20%, and potassium feldspar 20%. Full article
(This article belongs to the Special Issue High Performance Ceramics)
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Article
A Comparison of Methods for the Characterisation of Waste-Printed Circuit Boards
by , , , , , and
Metals 2021, 11(12), 1935; https://doi.org/10.3390/met11121935 - 30 Nov 2021
Abstract
Electronic waste is a growing waste stream globally. With 54.6 million tons generated in 2019 worldwide and with an estimated value of USD 57 billion, it is often referred to as an urban mine. Printed circuit boards (PCBs) are a major component of [...] Read more.
Electronic waste is a growing waste stream globally. With 54.6 million tons generated in 2019 worldwide and with an estimated value of USD 57 billion, it is often referred to as an urban mine. Printed circuit boards (PCBs) are a major component of electronic waste and are increasingly considered as a secondary resource for value recovery due to their high precious and base metals content. PCBs are highly heterogeneous and can vary significantly in composition depending on the original function. Currently, there are no standard methods for the characterisation of PCBs that could provide information relevant to value recovery operations. In this study, two pre-treatments, smelting and ashing of PCB samples, were investigated to determine the effect on PCB characterisation. In addition, to determine the effect of particle size and element-specific effects on the characterisation of PCBs, samples were processed using four different analytical methods. These included multi-acid digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) analysis, nitric acid digestion followed by X-ray fluorescence (XRF) analysis, multi-acid digestion followed by fusion digestion and analysis using ICP-OES, and microwave-assisted multi-acid digestion followed by ICP-OES analysis. In addition, a mixed-metal standard was created to serve as a reference material to determine the accuracy of the various analytical methods. Smelting and ashing were examined as potential pre-treatments before analytical characterisation. Smelting was found to reduce the accuracy of further analysis due to the volatilisation of some metal species at high temperatures. Ashing was found to be a viable pre-treatment. Of the four analytical methods, microwave-assisted multi-acid digestion offered the most precision and accuracy. It was found that the selection of analytical methods can significantly affect the accuracy of the observed metal content of PCBs, highlighting the need for a standardised method and the use of certified reference material. Full article
(This article belongs to the Special Issue Processing and Characterization of Metal Containing Wastes)
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Article
Importance of Visual Estimation of Coronary Artery Stenoses and Use of Functional Evaluation for Appropriate Guidance of Coronary Revascularization—Multiple Operator Evaluation
by , , , , , , , , , and
Diagnostics 2021, 11(12), 2241; https://doi.org/10.3390/diagnostics11122241 - 30 Nov 2021
Abstract
Background: Visual estimation (VE) of coronary stenoses is the first step during invasive coronary angiography. The aim of this study was to evaluate the accuracy of VE together with invasive functional assessment (IFA) in defining the functional significance (FS) of coronary stenoses based [...] Read more.
Background: Visual estimation (VE) of coronary stenoses is the first step during invasive coronary angiography. The aim of this study was to evaluate the accuracy of VE together with invasive functional assessment (IFA) in defining the functional significance (FS) of coronary stenoses based on the opinion of multiple operators. Methods: Fourteen independent operators visually evaluated 133 coronary lesions which had a previous FFR measurement, indicating the degree of stenosis (DS), FS and IFA intention. We determined the accuracy of FS prediction using several scenarios combining individual and group decision, considering IFA as deemed necessary by the operator or only in intermediate lesions. Results: The accuracy of VE in predicting FS was largely variable between operators (average 66.1%); it improved significantly when IFA was used either as per operator’s opinion (86.3%; p < 0.0001) or only in intermediate DS (82.9; p < 0.0001). There was no significant difference between using IFA per observer’s opinion or only in intermediate DS lesions (p = 0.166). The poorest accuracy of VE for FS was obtained in intermediate DS lesions (59.1%). Conclusions: There are significant inter-observer differences in reporting the degree of DS, while the accuracy of VE prediction of FS is also largely dependent on the operator, and the worst performance is obtained in the evaluation of intermediate DS. Full article
(This article belongs to the Special Issue Advance in Diagnostic and Management of Ischemic Heart Disease)
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Article
Effects of NaCl and CaCl2 Salinization on Morpho-Anatomical and Physiological Traits of Potted Callistemon citrinus Plants
by , , , , and
Forests 2021, 12(12), 1666; https://doi.org/10.3390/f12121666 - 30 Nov 2021
Abstract
The aim of this work was to assess the possible coordination mechanisms between leaf functional anatomical traits and physiological acclimation of potted Callistemon citrinus plants when subjected to two saline iso-osmotic solutions using NaCl or CaCl2. Digital image analysis was applied [...] Read more.
The aim of this work was to assess the possible coordination mechanisms between leaf functional anatomical traits and physiological acclimation of potted Callistemon citrinus plants when subjected to two saline iso-osmotic solutions using NaCl or CaCl2. Digital image analysis was applied to quantify anatomical parameters with a specific focus on the occurrence of signs of structural damage as well as on alterations, such as the occurrence of shrunk tissues and accumulation of phenolic compounds. Morpho-anatomical analyses were accompanied by measurements of leaf gas exchange and chlorophyll fluorescence emission. Results showed that C. citrinus plants, when irrigated with the CaCl2 solution, induced a leaf morpho-anatomical structure which did not allow the maintenance of high photosynthetic performance under such conditions, compared to both controls and plants treated with the iso-osmotic solution of NaCl. Data collected seem to suggest a close relationship between anatomical traits and eco-physiological strategies in maintaining the photosynthetic efficiency under saline stress conditions and highlight the fundamental role of leaf anatomy in imposing the limits of plant physiology. Full article
(This article belongs to the Section Urban Forestry)
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Article
Nonstandard Finite Difference Schemes for an SIR Epidemic Model
by , , and
Mathematics 2021, 9(23), 3082; https://doi.org/10.3390/math9233082 - 30 Nov 2021
Abstract
This paper aims to present two nonstandard finite difference (NFSD) methods to solve an SIR epidemic model. The proposed methods have important properties such as positivity and boundedness and they also preserve conservation law. Numerical comparisons confirm that the accuracy of our method [...] Read more.
This paper aims to present two nonstandard finite difference (NFSD) methods to solve an SIR epidemic model. The proposed methods have important properties such as positivity and boundedness and they also preserve conservation law. Numerical comparisons confirm that the accuracy of our method is better than that of other existing standard methods such as the second-order Runge–Kutta (RK2) method, the Euler method and some ready-made MATLAB codes. Full article
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Article
Molecular-Dynamics Simulations of the Emergence of Surface Roughness in a Polymer under Compression
by and
Materials 2021, 14(23), 7327; https://doi.org/10.3390/ma14237327 - 30 Nov 2021
Abstract
Roughness of surfaces is both surprisingly ubiquitous on all length scales and extremely relevant practically. The appearance of multi-scale roughness has been linked to avalanches and plastic deformation in metals. However, other, more-complex materials have mechanisms of plasticity that are significantly different from [...] Read more.
Roughness of surfaces is both surprisingly ubiquitous on all length scales and extremely relevant practically. The appearance of multi-scale roughness has been linked to avalanches and plastic deformation in metals. However, other, more-complex materials have mechanisms of plasticity that are significantly different from those of metals. We investigated the emergence of roughness in a polymer under compression. We performed molecular-dynamics simulations of a slab of solid polyvinyl alcohol that was compressed bi-axially, and we characterised the evolution of the surface roughness. We found significantly different behaviour than what was previously observed in similar simulations of metals. We investigated the differences and argue that the visco-elasticity of the material plays a crucial role. Full article
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Article
Avascular Necrosis Bone Complication after Active COVID-19 Infection: Preliminary Results
by , , , , , and
Medicina 2021, 57(12), 1311; https://doi.org/10.3390/medicina57121311 (registering DOI) - 30 Nov 2021
Abstract
Background and objectives: The course of SARS-CoV-2 (COVID-19) is still under analysis. The majority of complications arising from the infection are related to the respiratory system. The adverse effect of the viral infection on bone and joint tissue has also been observed. [...] Read more.
Background and objectives: The course of SARS-CoV-2 (COVID-19) is still under analysis. The majority of complications arising from the infection are related to the respiratory system. The adverse effect of the viral infection on bone and joint tissue has also been observed. Materials and Methods: We present a group of 10 patients with degeneration of large joints and adjacent epiphyses of long bones and the spine, with a background of bone infarctions and avascular necrosis (AVN) immediately after infection with the COVID-19 virus. In MR imaging, changes in the characteristics of AVN were documented. Results: Observation of this group showed a clear correlation among the history of COVID-19 disease in the patients, moderately severe symptoms, high levels of IgG antibodies, and the time of occurrence of joint changes. No other clinically significant complications were observed following COVID-19 infection in the study group. No other risk factors for AVN or autoimmune or degenerative diseases were found in the study group. The group of patients responded well to empirical treatment with steroids, which normalized acute inflammatory symptoms and pain in the joints. Conclusions: During coronavirus (COVID-19) infection, there are complications in the locomotor system, such as microembolism and the formation of AVN; hence, more research is needed. Full article
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Review
A Review of the Commercially Available ECG Detection and Transmission Systems—The Fuzzy Logic Approach in the Prevention of Sudden Cardiac Arrest
by
Micromachines 2021, 12(12), 1489; https://doi.org/10.3390/mi12121489 - 30 Nov 2021
Abstract
Sudden cardiac death (SCD) constitutes a major clinical and public health problem, whose death burden is comparable to the current worldwide pandemic. This comprehensive review encompasses the following topics: available rescue systems, wearable electrocardiograms (ECG), detection and transmission technology, and a newly developed [...] Read more.
Sudden cardiac death (SCD) constitutes a major clinical and public health problem, whose death burden is comparable to the current worldwide pandemic. This comprehensive review encompasses the following topics: available rescue systems, wearable electrocardiograms (ECG), detection and transmission technology, and a newly developed fuzzy logic algorithm (FA) for heart rhythm classification which is state-of-the art in the field of SCD prevention. Project “PROTECTOR”, the Polish Rapid Transtelephonic ECG to Obtain Resuscitation for development of a rapid rescue system for patients at risk of sudden cardiac arrest (SCA), is presented. If a lethal arrhythmia is detected on the basis of FA, the system produces an alarm signal audible for bystanders and transmits the alarm message along with location to the emergency medical center. Phone guided resuscitation can be started immediately because an automated external defibrillator (AED) localization map is available. An automatic, very fast diagnosis is a unique feature of the PROTECTOR prototype. The rapid detection of SCA is based on a processor characterized by 100% sensitivity and 97.8% specificity (as measured in the pilot studies). An integrated circuit which implements FA has already been designed and a diagnosis is made within few seconds, which is extremely important in ischemic brain damage prophylaxis. This circuit could be implemented in smart implants (Sis). Full article
(This article belongs to the Special Issue Smart Implants)
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Article
A Global Metabolic Map Defines the Effects of a Si-Based Biostimulant on Tomato Plants under Normal and Saline Conditions
by , , , , and
Metabolites 2021, 11(12), 820; https://doi.org/10.3390/metabo11120820 - 30 Nov 2021
Abstract
The ongoing unpredictability of climate changes is exponentially exerting a negative impact on crop production, further aggravating detrimental abiotic stress effects. Several research studies have been focused on the genetic modification of crop plants to achieve more crop resilience against such stress factors; [...] Read more.
The ongoing unpredictability of climate changes is exponentially exerting a negative impact on crop production, further aggravating detrimental abiotic stress effects. Several research studies have been focused on the genetic modification of crop plants to achieve more crop resilience against such stress factors; however, there has been a paradigm shift in modern agriculture focusing on more organic, eco-friendly and long-lasting systems to improve crop yield. As such, extensive research into the use of microbial and nonmicrobial biostimulants has been at the core of agricultural studies to improve crop growth and development, as well as to attain tolerance against several biotic and abiotic stresses. However, the molecular mechanisms underlying the biostimulant activity remain enigmatic. Thus, this study is a liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics approach to unravel the hypothetical biochemical framework underlying effects of a nonmicrobial biostimulant (a silicon-based formulation) on tomato plants (Solanum lycopersium) under salinity stress conditions. This metabolomics study postulates that Si-based biostimulants could alleviate salinity stress in tomato plants through modulation of the primary metabolism involving changes in the tricarboxylic acid cycle, fatty acid and numerous amino acid biosynthesis pathways, with further reprogramming of several secondary metabolism pathways such as the phenylpropanoid pathway, flavonoid biosynthesis pathways including flavone and flavanol biosynthesis. Thus, the postulated hypothetical framework, describing biostimulant-induced metabolic events in tomato plants, provides actionable knowledge necessary for industries and farmers to, confidently and innovatively, explore, design, and fully implement Si-based formulations and strategies into agronomic practices for sustainable agriculture and food production. Full article
(This article belongs to the Special Issue Plant Metabolomics II)
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