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Open AccessArticle
Sinularin, an Anti-Cancer Agent Causing Mitochondria-Modulated Apoptosis and Cytoskeleton Disruption in Human Hepatocellular Carcinoma
Int. J. Mol. Sci. 2021, 22(8), 3946; https://doi.org/10.3390/ijms22083946 (registering DOI) - 11 Apr 2021
Abstract
Liver cancer remains a leading cause of death, despite advances in anti-cancer therapies. To develop novel drugs, natural products are being considered as a good source for exploration. In this study, a natural product isolated from a soft coral was applied to evaluate [...] Read more.
Liver cancer remains a leading cause of death, despite advances in anti-cancer therapies. To develop novel drugs, natural products are being considered as a good source for exploration. In this study, a natural product isolated from a soft coral was applied to evaluate its anti-cancer activities in hepatocellular carcinoma SK-HEP-1 cells. Sinularin was determined to have half-maximal inhibitory concentration (IC50) values of ~10 μM after 24, 48, and 72 h. The TUNEL assay and annexin V/PI staining results showed that sinularin induced DNA fragmentation and apoptosis, respectively. An investigation at the molecular level demonstrated that the expression levels of cleaved caspases 3/9 were significantly elevated at 10 μM sinularin. Mitochondrial and intracellular reactive oxygen species (ROS) levels were significantly increased following sinularin treatment, which also affected the mitochondrial membrane potential. In addition, it significantly lowered the mitochondrial respiration parameters and extracellular acidification rates at 10 μM. Further investigation showed that sinularin significantly attenuated wound healing, cell migration, and potential colony formation at 10 μM. Fluorescence microscopic observations showed that the distribution of F-actin filaments was significantly altered at 10 μM sinularin. Supported by Western blot analyses, the expression levels of AKT, p-ERK (extracellular-signal-related kinase), vimentin and VEGF were significantly down-regulated, whereas p-p38, pJNK and E-cadherin were significantly increased. Overall, at the IC50 concentration, sinularin was able to significantly affect SK-HEP-1 cells. Full article
(This article belongs to the Section Biochemistry)
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Open AccessArticle
Development of Siloxane Coating with Oxide Fillers for Kesteritic (CZTS) Photovoltaic Systems
Energies 2021, 14(8), 2142; https://doi.org/10.3390/en14082142 (registering DOI) - 11 Apr 2021
Abstract
Photovoltaic systems (PV) based on Cu2ZnSn(S, Se)4 (CZTS) solar cells have demonstrated efficiency and high performance. According to the results of comparative studies, the kesterite structure has proven to be ecologically safe and less expensive than other photovoltaic systems. The [...] Read more.
Photovoltaic systems (PV) based on Cu2ZnSn(S, Se)4 (CZTS) solar cells have demonstrated efficiency and high performance. According to the results of comparative studies, the kesterite structure has proven to be ecologically safe and less expensive than other photovoltaic systems. The goal of the present study was to design a disposable high-temperature transparent electrical insulating coating to cover metal plates for photovoltaic devices based on CZTS. The solution was to replace electrically conductive metallics dispersed in a high-temperature siloxane coating with phonon thermal conductivity ceramic particles. Properties of the obtained coating were investigated using different methods. A mathematical model of thermal processes in the film during heating was also developed. For the control sample and the sample with a heat-conducting filler, a quantitative ratio of thermal conductivity was obtained. The research results confirmed the necessary properties of the coating, including resistance to short-term exposure to high temperatures during the synthesis of kesterite. Full article
(This article belongs to the Special Issue Energy Performance of the Photovoltaic Systems)
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Open AccessReview
Evaluation of Clinical Meaningfulness of Red Clover (Trifolium pratense L.) Extract to Relieve Hot Flushes and Menopausal Symptoms in Peri- and Post-Menopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Nutrients 2021, 13(4), 1258; https://doi.org/10.3390/nu13041258 (registering DOI) - 11 Apr 2021
Abstract
The meta-analysis presented in this article covered the efficacy of red clover isoflavones in relieving hot flushes and menopausal symptoms in perimenopausal and postmenopausal women. Studies were identified by MEDLINE (PubMed), Embase, and the Cochrane Library searches. The quality of the studies was [...] Read more.
The meta-analysis presented in this article covered the efficacy of red clover isoflavones in relieving hot flushes and menopausal symptoms in perimenopausal and postmenopausal women. Studies were identified by MEDLINE (PubMed), Embase, and the Cochrane Library searches. The quality of the studies was evaluated according to Cochrane criteria. A meta-analysis of eight trials (ten comparisons) demonstrated a statistically significant reduction in the daily incidence of hot flushes in women receiving red clover compared to those receiving placebo: weighted mean difference (WMD—weighted mean difference) −1.73 hot flushes per day, 95% CI (confidence interval) −3.28 to −0.18; p = 0.0292. Due to 87.34% homogeneity, the performed analysis showed substantive difference in comparisons of postmenopausal women with ≥5 hot flushes per day, when the follow-up period was 12 weeks, with an isoflavone dose of ≥80 mg/day, and when the formulations contained a higher proportion of biochanin A. The meta-analysis of included studies assessing the effect of red clover isoflavone extract on menopausal symptoms showed a statistically moderate relationship with the reduction in the daily frequency of hot flushes. However, further well-designed studies are required to confirm the present findings and to finally determine the effects of red clover on the relief of flushing episodes. Full article
(This article belongs to the Special Issue Nutrition Challenges for Middle-Aged and Older Women)
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Open AccessArticle
Magneto-Erythrocyte Membrane Vesicles’ Superior T2 MRI Contrast Agents to Magneto-Liposomes
Magnetochemistry 2021, 7(4), 51; https://doi.org/10.3390/magnetochemistry7040051 (registering DOI) - 11 Apr 2021
Abstract
Despite their high potential, most of the clinically approved iron oxide (IO)-based contrast agents for magnetic resonance imaging (MRI) have been withdrawn from the market either due to safety issues or lack of sales. To address this challenge, erythrocyte membranes have been used [...] Read more.
Despite their high potential, most of the clinically approved iron oxide (IO)-based contrast agents for magnetic resonance imaging (MRI) have been withdrawn from the market either due to safety issues or lack of sales. To address this challenge, erythrocyte membranes have been used to prepare IO-based T2 contrast agents with superior MRI properties and higher safety margin. A simple formulation procedure has been proposed, and the nanostructures’ morphology and physicochemical properties have been evaluated. We compared their performance in terms of contrast ability in MRI to the more clinically established magneto-liposomes and non-encapsulated nanoparticles (NPs). The encapsulation of 5-nm iron oxide nanoparticles (IO NPs) in the liposomes and erythrocyte membrane vesicles (EMVs) led to a significant improvement in their r2 relaxivity. r2 values increased to r2 = 188 ± 2 mM−1s−1 for magneto-liposomes and r2 = 269 ± 3 mM−1s−1 for magneto-erythrocyte membranes, compared to “free” IO NPs with (r2 = 12 ± 1 mM−1 s−1), measured at a 9.4 T MRI scanner. The superiority of magneto-erythrocyte membranes in terms of MRI contrast efficacy is clearly shown on T2-weighted MR images. Our study revealed the hemocompatibility of the developed contrast agents in the MRI-relevant concentration range. Full article
(This article belongs to the Special Issue Biomedical Application of Magnetic Nanoparticles in 2021)
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Open AccessArticle
Predictive Sustainability Model Based on the Theory of Planned Behavior Incorporating Ecological Conscience and Moral Obligation
Sustainability 2021, 13(8), 4248; https://doi.org/10.3390/su13084248 (registering DOI) - 11 Apr 2021
Abstract
Recent studies have highlighted the importance of research on consumers’ green behavior in emerging markets. This study aims to determine the variables of the theory of planned behavior (TPB) that influence green purchasing intentions in Mexico. Into the model, we incorporated ecological conscience, [...] Read more.
Recent studies have highlighted the importance of research on consumers’ green behavior in emerging markets. This study aims to determine the variables of the theory of planned behavior (TPB) that influence green purchasing intentions in Mexico. Into the model, we incorporated ecological conscience, moral obligation, and willingness to pay as additional variables. A sample of 300 consumers was obtained through an online survey and data were analyzed statistically using partial least squares structural equation modeling (PLS-SEM). The results revealed that perceived purchase control, ecological conscience, and moral obligation directly influence purchase intention. The study contributes to the current literature by strengthening the existing knowledge about the factors that influence the purchasing behavior of green products in emerging countries. Full article
(This article belongs to the Section Economic and Business Aspects of Sustainability)
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Open AccessArticle
Willingness to Pay for Improved Operations and Maintenance Services of Gravity-Fed Water Schemes in Idjwi Island (Democratic Republic of the Congo)
Water 2021, 13(8), 1050; https://doi.org/10.3390/w13081050 (registering DOI) - 11 Apr 2021
Abstract
Developing understanding of the economic value that communities ascribe to improved operations and maintenance (O&M) services has emerged as a key factor in achieving financial sustainability for rural water systems. The present study elicits household willingness to pay (WTP) for improved O&M services [...] Read more.
Developing understanding of the economic value that communities ascribe to improved operations and maintenance (O&M) services has emerged as a key factor in achieving financial sustainability for rural water systems. The present study elicits household willingness to pay (WTP) for improved O&M services in eight gravity-fed water schemes in Idjwi Island (Democratic Republic of the Congo, DRC). A contingent valuation survey was implemented through an open-ended format questionnaire to 1105 heads of household and a log-linear regression model was employed to assess the factors influencing higher values. Findings show an average willingness to pay of 327 Congolese Francs (CDF) per month and 36 CDF per bucket. Results also indicate a significant WTP differential among studied schemes. The analysis of the conditioning factors reveals that the level of excludability, the participation in management meetings and the time employed in fetching water from an improved source are contingent with their WTP. The findings of this study are important for development agents trying to establish acceptable, affordable and practicable tariffs that help finance reliable rural water systems in Idjwi. Full article
(This article belongs to the Section Water Resources Management, Policy and Governance)
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Open AccessArticle
Global Visualization of Compressible Swept Convex-Corner Flow Using Pressure-Sensitive Paint
Aerospace 2021, 8(4), 106; https://doi.org/10.3390/aerospace8040106 (registering DOI) - 11 Apr 2021
Abstract
This study used pressure-sensitive paint (PSP) and determined the surface pressure distributions for a compressible swept convex-corner flow. The freestream Mach numbers were 0.64 and 0.83. The convex-corner angle and swept angle were, respectively, 10–17° and 5–15°. Expansion and compression near the corner [...] Read more.
This study used pressure-sensitive paint (PSP) and determined the surface pressure distributions for a compressible swept convex-corner flow. The freestream Mach numbers were 0.64 and 0.83. The convex-corner angle and swept angle were, respectively, 10–17° and 5–15°. Expansion and compression near the corner apex were clearly visualized. For the test case of shock-induced boundary layer separation, there were greater spanwise pressure gradient and curved shocks. The acquired PSP data agree with the experimental data measured using the Kulite pressure transducers for a subsonic expansion flow. For a transonic expansion flow, the discrepancy was significant. The assumption of a constant recovery factor is not valid in the separation region, and temperature correction for PSP measurements is required. Full article
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Open AccessArticle
Do Orthopedic Surgeons or Neurosurgeons Detect More Hip Disorders in Patients with Hip-Spine Syndrome? A Nationwide Database Study
Brain Sci. 2021, 11(4), 485; https://doi.org/10.3390/brainsci11040485 (registering DOI) - 11 Apr 2021
Abstract
Background: Disorders of the hip and lumbar spine can create similar patterns of pain and dysfunction. It is unknown whether all surgeons, regardless of orthopedic or neurosurgery training, investigate and diagnose concurrent hip and spine pathology at the same rate. Methods: [...] Read more.
Background: Disorders of the hip and lumbar spine can create similar patterns of pain and dysfunction. It is unknown whether all surgeons, regardless of orthopedic or neurosurgery training, investigate and diagnose concurrent hip and spine pathology at the same rate. Methods: Data were retrieved from Taiwan’s National Health Insurance Research Database (NHIRD). Enrolled patients were stratified into hip and spine surgery at the same admission (Both), hip surgery before spine surgery (HS), or spine surgery before hip surgery (SH). The SH group was further subdivided based on whether spine surgery was performed by an orthopedic surgeon (OS) or neurosurgeon (NS), and differences in preoperative radiographic examinations and diagnoses were collected and analyzed. Results: In total, 1824 patients received lumbar spine surgery within 1 year before or after hip replacement surgery. Of these, 103 patients had spine and hip surgery in the same admission (Both), 1290 patients had spine surgery before hip surgery (SH), and 431 patients had hip surgery before spine surgery (HS). In the SH group, patients were categorized into spine surgery by orthopedic surgeons (OS) (n = 679) or neurosurgeons (NS) (n = 522). In the SH group, orthopedic surgeons investigated hip pathology with X-rays more often (52.6% vs. 38.1%, p < 0.001) and diagnosed more cases of hip disease (43.6% vs. 28.9%, p < 0.001) than neurosurgeons. Conclusions: Of patients in Taiwan’s NHIRD who had concurrent surgical degenerative hip and lumbar spine disorders who had spine surgery before hip surgery, orthopedic surgeons obtained hip images and made hip-related diagnoses more frequently than did neurosurgeons. Full article
(This article belongs to the Special Issue Neurosurgery and Neuroanatomy)
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Open AccessArticle
Quality Characteristics and Consumer Acceptance of High-Moisture Mozzarella Obtained from Heat-Treated Goat Milk
Foods 2021, 10(4), 833; https://doi.org/10.3390/foods10040833 (registering DOI) - 11 Apr 2021
Abstract
High-moisture mozzarella is a pasta filata cheese manufactured from cow or buffalo milk that has spread all over the world. Its manufacturing from the milk of small ruminants (goat and sheep) has been recently proposed to innovate this ailing sector. Previously, a protocol [...] Read more.
High-moisture mozzarella is a pasta filata cheese manufactured from cow or buffalo milk that has spread all over the world. Its manufacturing from the milk of small ruminants (goat and sheep) has been recently proposed to innovate this ailing sector. Previously, a protocol was reported for making goat mozzarella from unpasteurized milk but, according to legislation, the microbiological safety of raw milk fresh cheeses is not guaranteed. In the present research, two new protocols were tested for producing mozzarella from pasteurized milk prepared by two different low-temperature long-time treatments (67 °C or 63 °C × 30 min). The obtained cheeses were subjected to physical–chemical and microbiological analyses and to consumer testing. The results showed that the heat treatments caused longer coagulation times than those reported in the literature, despite pre-acidification (at pH 5.93 or 6.35) having been performed to counterbalance the expected worsening of the coagulation aptitude. The obtained products showed differences in the chemical composition, texture, proteolysis, and lipolysis. Both pasteurization and pre-acidification played a role in determining these variations. Consumer testing indicated that mozzarella obtained from milk heated at the lower temperature and coagulated at a higher pH reached a good level of appreciation (62%). Full article
(This article belongs to the Section Dairy)
Open AccessArticle
Plasticized Polymer Blend Electrolyte Based on Chitosan for Energy Storage Application: Structural, Circuit Modeling, Morphological and Electrochemical Properties
Polymers 2021, 13(8), 1233; https://doi.org/10.3390/polym13081233 (registering DOI) - 11 Apr 2021
Abstract
Chitosan (CS)-dextran (DN) biopolymer electrolytes doped with ammonium iodide (NH4I) and plasticized with glycerol (GL), then dispersed with Zn(II)-metal complex were fabricated for energy device application. The CS:DN:NH4I:Zn(II)-complex was plasticized with various amounts of GL and the impact of [...] Read more.
Chitosan (CS)-dextran (DN) biopolymer electrolytes doped with ammonium iodide (NH4I) and plasticized with glycerol (GL), then dispersed with Zn(II)-metal complex were fabricated for energy device application. The CS:DN:NH4I:Zn(II)-complex was plasticized with various amounts of GL and the impact of used metal complex and GL on the properties of the formed electrolyte were investigated.The electrochemical impedance spectroscopy (EIS) measurements have shown that the highest conductivity for the plasticized system was 3.44 × 10−4 S/cm. From the x-ray diffraction (XRD) measurements, the plasticized electrolyte with minimum degree of crystallinity has shown the maximum conductivity. The effect of (GL) plasticizer on the film morphology was studied using FESEM. It has been confirmed via transference number analysis (TNM) that the transport mechanism in the prepared electrolyte is predominantly ionic in nature with a high transference number of ion (ti)of 0.983. From a linear sweep voltammetry (LSV) study, the electrolyte was found to be electrochemically constant as the voltage sweeps linearly up to 1.25 V. The cyclic voltammetry (CV) curve covered most of the area of the current–potential plot with no redox peaks and the sweep rate was found to be affecting the capacitance. The electric double-layer capacitor (EDLC) has shown a great performance of specific capacitance (108.3 F/g), ESR(47.8 ohm), energy density (12.2 W/kg) and power density (1743.4 W/kg) for complete 100 cycles at a current density of 0.5 mA cm−2. Full article
(This article belongs to the Special Issue Proton/Anion-Conducting Polymers for Energy Conversion Systems)
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Open AccessArticle
Investigation: Cutting Transport Mechanism in Inclined Well Section under Pulsed Drilling Fluid Action
Energies 2021, 14(8), 2141; https://doi.org/10.3390/en14082141 (registering DOI) - 11 Apr 2021
Abstract
Due to gravity, drilling cuttings are easily accumulated in an inclined well section, ultimately forming a cuttings bed, which places the drill pipe under strong friction torque. In severe cases, this can cause dragging, stuck drills, and broken drill tools. Because conventional drilling [...] Read more.
Due to gravity, drilling cuttings are easily accumulated in an inclined well section, ultimately forming a cuttings bed, which places the drill pipe under strong friction torque. In severe cases, this can cause dragging, stuck drills, and broken drill tools. Because conventional drilling fluids are difficult to prevent the formation of cuttings in inclined well sections, a method of carrying cuttings with the pulsed drilling fluid to improve wellbore cleanness is proposed. Experiments and numerical simulations are conducted to investigate the effects of cuttings bed transport velocity, cuttings size, cuttings height, drill pipe rotation speed, cuttings bed mass, and roughness height. The optimal pulse parameters are determined per their respective impact on cuttings transport concerning varied periods, amplitudes, and duty cycles of the pulsed drilling fluid. Compared to cuttings transport under the conventional drilling fluid flow rate, the pulsed drilling fluid produces the turbulent dissipation rate, increases cuttings transport velocity, and thus improves the wellbore clearance rate. Full article
(This article belongs to the Section Energy Fundamentals and Conversion)
Open AccessArticle
Growth Forms and Functional Guilds Distribution of Soil Fungi in Coastal Versus Inland Sites of Victoria Land, Antarctica
Biology 2021, 10(4), 320; https://doi.org/10.3390/biology10040320 (registering DOI) - 11 Apr 2021
Abstract
In Victoria Land, Antarctica, ice-free areas are restricted to coastal regions and dominate the landscape of the McMurdo Dry Valleys. These two environments are subjected to different pressures that determine the establishment of highly adapted fungal communities. Within the kingdom of fungi, filamentous, [...] Read more.
In Victoria Land, Antarctica, ice-free areas are restricted to coastal regions and dominate the landscape of the McMurdo Dry Valleys. These two environments are subjected to different pressures that determine the establishment of highly adapted fungal communities. Within the kingdom of fungi, filamentous, yeasts and meristematic/microcolonial growth forms on one side and different lifestyles on the other side may be considered adaptive strategies of particular interest in the frame of Antarctic constraints. In this optic, soil fungal communities from both coastal and Dry Valleys sites, already characterized thorough ITS1 metabarcoding sequencing, have been compared to determine the different distribution of phyla, growth forms, and lifestyles. Though we did not find significant differences in the richness between the two environments, the communities were highly differentiated and Dry Valleys sites had a higher evenness compared to coastal ones. Additionally, the distribution of different growth forms and lifestyles were well differentiated, and their diversity and composition were likely influenced by soil abiotic parameters, among which soil granulometry, pH, P, and C contents were the potential main determinants. Full article
(This article belongs to the Special Issue Diversity of Soil Fungal Communities)
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Open AccessReview
A Brief Review on the Sensor Measurement Solutions for the Ten-Meter Walk Test
Computers 2021, 10(4), 49; https://doi.org/10.3390/computers10040049 (registering DOI) - 11 Apr 2021
Abstract
The wide-spread use of wearables and the adoption of the Internet of Things (IoT) paradigm provide an opportunity to use mobile-device sensors for medical applications. Sensors available in the commonly used devices may inspire innovative solutions for physiotherapy striving for accurate and early [...] Read more.
The wide-spread use of wearables and the adoption of the Internet of Things (IoT) paradigm provide an opportunity to use mobile-device sensors for medical applications. Sensors available in the commonly used devices may inspire innovative solutions for physiotherapy striving for accurate and early identification of various pathologies. An essential and reliable performance measure is the ten-meter walk test, which is employed to determine functional mobility, gait, and vestibular function. Sensor-based approaches can identify the various test phases and their segmented duration, among other parameters. The measurement parameter primarily used is related to the tests’ duration, and after identifying patterns, a variety of physical treatments can be recommended. This paper reviews multiple studies focusing on automated measurements of the ten-meter walk test with different sensors. Most of the analyzed studies measure similar parameters as traditional methods, such as velocity, duration, and other involuntary and dangerous patients’ movements after stroke. That provides an opportunity to measure different parameters that can be later fed into machine learning models for analyzing more complex patterns. Full article
(This article belongs to the Special Issue Artificial Intelligence for Health)
Open AccessArticle
Assessment and Integration of Renewable Energy Resources Installations with Reactive Power Compensator in Indian Utility Power System Network
Electronics 2021, 10(8), 912; https://doi.org/10.3390/electronics10080912 (registering DOI) - 11 Apr 2021
Abstract
Renewable energy (RE) resource assessment is essential for planners and investors to increase its penetration capacity, and improve social and economic security. Integration of renewable power generations (RPGs) and reactive power compensators (RPCs) offer potential benefits to the existing power system network by [...] Read more.
Renewable energy (RE) resource assessment is essential for planners and investors to increase its penetration capacity, and improve social and economic security. Integration of renewable power generations (RPGs) and reactive power compensators (RPCs) offer potential benefits to the existing power system network by providing a prospect for voltage control, reduction in power losses, sustainability, and reliability improvement. There are proven outcomes with these RPGs and RPCs placement in distribution systems. This work proposes a candidature location and sizing of RPGs and RPCs optimally in the Indian utility transmission power system network. The foremost purpose of this integrated operation at multiple nodes is to increase the performance of the power system concerning power loss and voltage deviation reductions, and voltage stability improvement. The loss sensitivity factor (LSF) based particle swarm optimization (PSO) technique is adapted for finding the candidature locations and sizing the RPGs and RPCs under five different configurations. Simulation outcomes display the proposed methodology can lead to extensive performance enhancement in the power system towards the sustainable development of electric energy transactions. Further, renewable resource assessment is carried out to find the viability of the candidature locations. The potential of wind and solar energy resources is assessed widely and suitable tools are used to evaluate the power extraction through RE at these selected locations. The results show that the candidature locations have great potential to evacuate the energy, which can effectively improve the existing power system technically and economically. Additionally, it is attested that the RPGs can also be utilized for power system enhancement. Full article
(This article belongs to the Section Systems & Control Engineering)
Open AccessArticle
Experimental and Theoretical Validation of One Diode and Three Parameters–Based PV Models
Energies 2021, 14(8), 2140; https://doi.org/10.3390/en14082140 (registering DOI) - 11 Apr 2021
Abstract
The present paper defines and assesses a new simplified method to represent the photovoltaic (PV) modules’ electrical behavior, based on the commonly used one diode and three parameters (1D + 3P) model, addressing two main objectives. The first one is to quantify and [...] Read more.
The present paper defines and assesses a new simplified method to represent the photovoltaic (PV) modules’ electrical behavior, based on the commonly used one diode and three parameters (1D + 3P) model, addressing two main objectives. The first one is to quantify and assess, at different operating conditions, the PV modules electrical behavior estimations’ accuracy provided by the well-known 1D + 3P, through a comparison based on experimental and theoretical results. The second one concerns the performance assessment of the 1D + 3P model’s suggested approximation, aiming at simplifying the mathematics instead of solving complex iterative equations, which hinges on higher computational time to obtain accurate results. Hence, experimental and theoretical data were considered, aiming at performing a thorough comparison with more than 17,000 PV modules being assessed, which was achieved by using both the California Energy Commission (CEC) database and PVsyst software. The findings show that the already known 1D + 3P model delivers satisfactory power output estimations for crystalline silicon modules and high irradiance conditions. However, its performance worsens when considering Low Irradiance and thin-film technology. In comparison with the original model, accurate results were obtained with the new simplified suggested 1D + 3P for all irradiance conditions and technologies assessed, thus proving its validity and capability of circumventing the aforementioned challenges. Full article
(This article belongs to the Special Issue Hybrid Solar Photovoltaic, Thermoelectric, and Thermal Modules)
Open AccessArticle
Research on Cavitation of the Rotating-Sleeve Distributing Flow System Considering Different Cam Groove Profiles
Energies 2021, 14(8), 2139; https://doi.org/10.3390/en14082139 (registering DOI) - 11 Apr 2021
Abstract
Reciprocating piston pumps are widely used in various fields, such as automobiles, ships, aviation, and engineering machinery. Conventional reciprocating piston pump distributing flow (RPPDF) systems have the disadvantages of a loose structure and low volumetric efficiency, as well as affected positively by the [...] Read more.
Reciprocating piston pumps are widely used in various fields, such as automobiles, ships, aviation, and engineering machinery. Conventional reciprocating piston pump distributing flow (RPPDF) systems have the disadvantages of a loose structure and low volumetric efficiency, as well as affected positively by the operating frequency. In this paper, a novel rotating-sleeve distributing flow (RSDF) system is presented for bridging these drawbacks, as well as structurally improved to overcome the inoperable and challenging problems in oil intake and discharge found in the experiment. Moreover, the Singhal cavitation model specifically for the RSDF system and four-cam groove profiles (CGPs) is established. To find the most suitable CGP to reduce the RSDF’s cavitation, the cavitation of the RSDF system was investigated, combining with simulations by taking into account the gap among the rotating sleeve, the pump chamber, and experiments on four presented CGPs. Simulation results based on vapor volume fraction, cavitation ratio, and volumetric efficiency show that the linear profile’s cavitation is the weakest. Finally, the correctness of the simulation is verified through orthogonal experiments. This research is of great significance to the further development of the RSDF system; more important, it has great potential to promote the reform of the RPPDF method. Full article
Open AccessArticle
Exogenous Gibberellic Acid or Dilute Bee Honey Boosts Drought Stress Tolerance in Vicia faba by Rebalancing Osmoprotectants, Antioxidants, Nutrients, and Phytohormones
Plants 2021, 10(4), 748; https://doi.org/10.3390/plants10040748 (registering DOI) - 11 Apr 2021
Abstract
The use of growth regulators such as gibberellic acid (GA3) and biostimulants, including diluted bee honey (Db-H) can improve drought tolerance in many crops, including the faba bean (Vicia faba L.). Db-H contains high values of osmoprotectants, mineral nutrients, vitamins, [...] Read more.
The use of growth regulators such as gibberellic acid (GA3) and biostimulants, including diluted bee honey (Db-H) can improve drought tolerance in many crops, including the faba bean (Vicia faba L.). Db-H contains high values of osmoprotectants, mineral nutrients, vitamins, and many antioxidants making it an effective growth regulator against environmental stress effects. Therefore, the present study was planned to investigate the potential improvement in the faba bean plant performance (growth and productivity) under full watering (100% of crop evapotranspiration (ETc)) and drought stress (60% of ETc) by foliar application of GA3 (20 mg L−1) or Db-H (20 g L−1). The ameliorative impacts of these growth regulators on growth, productivity, physio-biochemical attributes, nutrient status, antioxidant defense system, and phytohormones were evaluated. GA3 or Db-H attenuated the negative influences of drought stress on cell membrane stability, ion leakage, relative water content, nutrient status, leaf pigments related to photosynthesis (chlorophylls and carotenoids), and efficiency of the photosystem II (PSII in terms of Fv/Fm and performance index), thus improving faba bean growth, green pod yield, and water use efficiency. Drought stress caused an abnormal state of nutrients and photosynthetic machinery due to increased indicators of oxidative stress (malondialdehyde (MDA), hydrogen peroxide (H2O2) and superoxide (O2•−)), associated with increased osmoprotectants (proline, glycine betaine, soluble sugars, and soluble protein), non-enzymatic antioxidants (ascorbic acid, glutathione, and α-tocopherol), and enzymatic antioxidant activities (superoxide dismutase, catalase, glutathione reductase, and ascorbate peroxidase). However, foliar-applied GA3 or Db-H mediated further increases in osmoprotectants, antioxidant capacity, GA3, indole-3-acetic acid, and cytokinins, along with decreased levels of MDA and abscisic acid. These results suggest the use of GA3 or Db-H at the tested concentrations to mitigate drought-induced damage in bean plants to obtain satisfactory growth and productivity under a water deficit of up to 40%. Full article
(This article belongs to the Special Issue Abiotic Stress Tolerance in Crop and Medical Plants)
Open AccessFeature PaperArticle
Identification and Characterization of a Novel Genomic Island Harboring Cadmium and Arsenic Resistance Genes in Listeria welshimeri
Biomolecules 2021, 11(4), 560; https://doi.org/10.3390/biom11040560 (registering DOI) - 11 Apr 2021
Abstract
Listeria monocytogenes, the bacterial foodborne pathogen responsible for the severe disease listeriosis, frequently exhibits heavy metal resistance. Concurrent resistance to cadmium and arsenic in L. monocytogenes is strongly associated with the 35-kb chromosomal island LGI2. LGI2 has been encountered repeatedly among L. monocytogenes [...] Read more.
Listeria monocytogenes, the bacterial foodborne pathogen responsible for the severe disease listeriosis, frequently exhibits heavy metal resistance. Concurrent resistance to cadmium and arsenic in L. monocytogenes is strongly associated with the 35-kb chromosomal island LGI2. LGI2 has been encountered repeatedly among L. monocytogenes serotype 4b hypervirulent clones but, surprisingly, not among non-pathogenic Listeria spp. Here we describe a novel LGI2 variant, LGI2-3, in two L. welshimeri strains from an urban aquatic environment. Whole genome sequence analysis revealed that the genomes were closely related except for one prophage region and confirmed a chromosomally integrated LGI2-3. It harbored a cystathionine beta-lyase gene previously only encountered in LGI2-1 of L. monocytogenes clonal complex 1 but was otherwise most closely related to LGI2. LGI2-3 harbored a novel cadAC cassette (cadA7C7) that, like LGI2′s cadA4C4, was associated with lower-level tolerance to cadmium (MIC 50 μg/mL) than other cadAC cassettes (MIC ≥ 140 μg/mL). CadA sequence analysis identified two amino acids that may be important for mediating different levels of cadmium tolerance. Our findings clearly demonstrated the potential for LGI2-like islands to be harbored by non-pathogenic Listeria spp. and generate intriguing hypotheses on the genetic diversity mediated by this island and its transfer among Listeria spp. Full article
(This article belongs to the Special Issue Recent Advance of Listeria)
Open AccessArticle
Comparison of Bioelectrical Impedance-Based Methods on Body Composition in Young Patients with Obesity
Children 2021, 8(4), 295; https://doi.org/10.3390/children8040295 (registering DOI) - 11 Apr 2021
Abstract
(1) Background: The determination of body composition is an important method to investigate patients with obesity and to evaluate the efficacy of individualized medical interventions. Bioelectrical impedance-based methods are non-invasive and widely applied but need to be validated for their use in young [...] Read more.
(1) Background: The determination of body composition is an important method to investigate patients with obesity and to evaluate the efficacy of individualized medical interventions. Bioelectrical impedance-based methods are non-invasive and widely applied but need to be validated for their use in young patients with obesity. (2) Methods: We compiled data from three independent studies on children and adolescents with obesity, measuring body composition with two bioelectrical impedance-based devices (TANITA and BIACORPUS). For a small patient group, additional data were collected with air displacement plethysmography (BOD POD) and dual-energy X-ray absorptiometry (DXA). (3) Results: Our combined data on 123 patients (age: 6–18 years, body mass index (BMI): 21–59 kg/m²) and the individual studies showed that TANITA and BIACORPUS yield significantly different results on body composition, TANITA overestimating body fat percentage and fat mass relative to BIACORPUS and underestimating fat-free mass (p < 0.001 for all three parameters). A Bland–Altman plot indicated little agreement between methods, which produce clinically relevant differences for all three parameters. We detected gender-specific differences with both methods, with body fat percentage being lower (p < 0.01) and fat-free mass higher (p < 0.001) in males than females. (4) Conclusions: Both bioelectrical impedance-based methods provide significantly different results on body composition in young patients with obesity and thus cannot be used interchangeably, requiring adherence to a specific device for repetitive measurements to ascertain comparability of data. Full article
(This article belongs to the Special Issue Body Composition in Children)
Open AccessArticle
Rapid Decline of Serum Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) in Non-Cirrhotic Patients with Chronic Hepatitis C Infection Receiving Direct-Acting Antiviral Therapy
J. Clin. Med. 2021, 10(8), 1621; https://doi.org/10.3390/jcm10081621 (registering DOI) - 11 Apr 2021
Abstract
Direct-acting antivirals (DAAs) efficiently eradicate the hepatitis C virus (HCV). Low-density lipoprotein (LDL) levels increase rapidly upon DAA treatment. Proprotein convertase subtilisin/kexin 9 (PCSK9) induces degradation of the hepatic LDL receptor and thereby elevates serum LDL. The aim of this study was to [...] Read more.
Direct-acting antivirals (DAAs) efficiently eradicate the hepatitis C virus (HCV). Low-density lipoprotein (LDL) levels increase rapidly upon DAA treatment. Proprotein convertase subtilisin/kexin 9 (PCSK9) induces degradation of the hepatic LDL receptor and thereby elevates serum LDL. The aim of this study was to determine serum PCSK9 concentrations during and after DAA therapy to identify associations with LDL levels. Serum PCSK9 was increased in 82 chronic HCV-infected patients compared to 55 patients not infected with HCV. Serum PCSK9 was low in HCV patients with liver cirrhosis, but patients with HCV-induced liver cirrhosis still exhibited higher serum PCSK9 than patients with non-viral liver cirrhosis. Serum PCSK9 correlated with measures of liver injury and inflammation in cirrhotic HCV patients. In patients without liver cirrhosis, a positive association of serum PCSK9 with viral load existed. Serum PCSK9 was not different between viral genotypes. Serum PCSK9 did not correlate with LDL levels in HCV patients irrespective of cirrhotic status. Serum PCSK9 was reduced, and LDL was increased at four weeks after DAA therapy start in non-cirrhotic HCV patients. Serum PCSK9 and LDL did not changeupon DAA treatment in the cirrhotic group. The rapid decline of PCSK9 after the start of DAA therapy in conjunction with raised LDL levels in non-cirrhotic HCV patients shows that these changes are not functionally related. Full article
(This article belongs to the Section Gastroenterology & Hepatopancreatobiliary Medicine)
Open AccessArticle
Responses of Soil Abiotic Properties and Microbial Community Structure to 25-Year Cucumber Monoculture in Commercial Greenhouses
Agriculture 2021, 11(4), 341; https://doi.org/10.3390/agriculture11040341 (registering DOI) - 11 Apr 2021
Abstract
Cucumber monoculture could cause soil salinization and acidification, soilborne diseases, and eventually yield loss. However, after a 25-year monoculture in Wafangdian county, Liaoning province, China, cucumber yields have remained satisfactory. In the present study, we investigated how the soil abiotic and biotic properties, [...] Read more.
Cucumber monoculture could cause soil salinization and acidification, soilborne diseases, and eventually yield loss. However, after a 25-year monoculture in Wafangdian county, Liaoning province, China, cucumber yields have remained satisfactory. In the present study, we investigated how the soil abiotic and biotic properties, in addition to soil rhizosphere microbial community structure in the greenhouses, could still sustain plant growth after such long-term monoculture production. Soil organic carbon, total nitrogen, and available nitrogen were accumulated significantly after monoculture. Such increasing soil fertility was accompanied by increased soil microbial abundance, which reshaped soil microbial community structure. Both bacterial and fungal diversity, including observed and estimated richness, Heip evenness, and Shannon diversity, decreased significantly, while the monoculture period had a greater influence on fungal diversity than on bacterial diversity. Although the high accumulation of soil nutrients increased soil salinity and acidity, the abundance of potential plant pathogenic fungi did not show an obvious increase. These results indicated that maintaining soil abiotic and biotic properties using organic fertilizers and balanced chemical fertilizers, especially improving potassium fertilizer application, could be useful measurements for the sustainable development of greenhouse vegetable production. In addition, appropriate management strategies should be considered to reduce the potential risk of soil salinization. Full article
(This article belongs to the Special Issue Fertilizer Use, Soil Health and Agricultural Sustainability)
Open AccessReview
Insights on Cadmium Removal by Bioremediation: The Case of Haloarchaea
Microbiol. Res. 2021, 12(2), 354-375; https://doi.org/10.3390/microbiolres12020024 (registering DOI) - 11 Apr 2021
Abstract
Although heavy metals are naturally found in the environment as components of the earth’s crust, environmental pollution by these toxic elements has increased since the industrial revolution. Some of them can be considered essential, since they play regulatory roles in different biological processes; [...] Read more.
Although heavy metals are naturally found in the environment as components of the earth’s crust, environmental pollution by these toxic elements has increased since the industrial revolution. Some of them can be considered essential, since they play regulatory roles in different biological processes; but the role of other heavy metals in living tissues is not clear, and once ingested they can accumulate in the organism for long periods of time causing adverse health effects. To mitigate this problem, different methods have been used to remove heavy metals from water and soil, such as chelation-based processes. However, techniques like bioremediation are leaving these conventional methodologies in the background for being more effective and eco-friendlier. Recently, different research lines have been promoted, in which several organisms have been used for bioremediation approaches. Within this context, the extremophilic microorganisms represent one of the best tools for the treatment of contaminated sites due to the biochemical and molecular properties they show. Furthermore, since it is estimated that 5% of industrial effluents are saline and hypersaline, halophilic microorganisms have been suggested as good candidates for bioremediation and treatment of this kind of samples. These microorganisms, and specifically the haloarchaea group, are of interest to design strategies aiming the removal of polluting compounds due to the efficiency of their metabolism under extreme conditions and their significant tolerance to highly toxic compounds such as heavy metals, bromate, nitrite, chlorate, or perchlorate ions. However, there are still few trials that have proven the bioremediation of environments contaminated with heavy metals using these microorganisms. This review analyses scientific literature focused on metabolic capabilities of haloarchaea that may allow these microbes to tolerate and eliminate heavy metals from the media, paying special attention to cadmium. Thus, this work will shed light on potential uses of haloarchaea in bioremediation of soils and waters negatively affected by heavy metals, and more specifically by cadmium. Full article

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