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Open AccessArticle
Electrohydrodynamic Atomization for Minimum Quantity Lubrication (EHDA-MQL) in End Milling Ti6Al4V Titanium Alloy
J. Manuf. Mater. Process. 2020, 4(3), 70; https://doi.org/10.3390/jmmp4030070 (registering DOI) - 13 Jul 2020
Abstract
Titanium alloy Ti6Al4V is a difficult-to-machine material which is extensively used in the aerospace and medical industries. Machining titanium is associated with a short tool life and low productivity. In this paper, a new cooling-lubrication system based on electrohydrodynamic atomization was designed, manufactured [...] Read more.
Titanium alloy Ti6Al4V is a difficult-to-machine material which is extensively used in the aerospace and medical industries. Machining titanium is associated with a short tool life and low productivity. In this paper, a new cooling-lubrication system based on electrohydrodynamic atomization was designed, manufactured and tested and the relevant theory was developed. The major novelty of the system lies within the use of electrohydrodynamic atomization (EHDA) and a three-electrode setup for generating lubricant droplets. The system was tested and compared with that of flood, minimum quantity lubrication (MQL) and compressed air machining. The proposed system can extend the tool life by 6 and 22 times when compared with MQL and flood cooling, respectively. This is equivalent to more than 170 min tool life at 120 m/min cutting speed allowing for significant productivity gains in machining Ti6Al4V. Full article
(This article belongs to the Special Issue Advanced Manufacturing and Machining Processes)
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Open AccessEditorial
Special Issue on Clinical Medicine for Healthcare and Sustainability
J. Clin. Med. 2020, 9(7), 2206; https://doi.org/10.3390/jcm9072206 (registering DOI) - 13 Jul 2020
Abstract
Recently, due to the advancement of network technology, big data and artificial intelligence, the healthcare industry has undergone many sector-wide changes. Medical care has not only changed from passive and hospital-centric to preventative and personalized, but also from disease-centric to health-centric. Healthcare systems [...] Read more.
Recently, due to the advancement of network technology, big data and artificial intelligence, the healthcare industry has undergone many sector-wide changes. Medical care has not only changed from passive and hospital-centric to preventative and personalized, but also from disease-centric to health-centric. Healthcare systems and basic medical research are becoming more intelligent and being implemented in biomedical engineering. This Special Issue on “Clinical Medicine for Healthcare and Sustainability” selected 30 excellent papers from 160 papers presented in IEEE ECBIOS 2019 on the topic of clinical medicine for healthcare and sustainability. Our purpose is to encourage scientists to propose their experiments and theoretical researches to facilitate the scientific prediction and influential assessment of global change and development. Full article
(This article belongs to the Special Issue Clinical Medicine for Healthcare and Sustainability)
Open AccessReview
A Survey of Reported Disease-Related Mutations in the MRE11-RAD50-NBS1 Complex
Cells 2020, 9(7), 1678; https://doi.org/10.3390/cells9071678 (registering DOI) - 13 Jul 2020
Abstract
The MRE11-RAD50-NBS1 (MRN) protein complex is one of the primary vehicles for repairing DNA double strand breaks and maintaining the genomic stability within the cell. The role of the MRN complex to recognize and process DNA double-strand breaks as well as signal other [...] Read more.
The MRE11-RAD50-NBS1 (MRN) protein complex is one of the primary vehicles for repairing DNA double strand breaks and maintaining the genomic stability within the cell. The role of the MRN complex to recognize and process DNA double-strand breaks as well as signal other damage response factors is critical for maintaining proper cellular function. Mutations in any one of the components of the MRN complex that effect function or expression of the repair machinery could be detrimental to the cell and may initiate and/or propagate disease. Here, we discuss, in a structural and biochemical context, mutations in each of the three MRN components that have been associated with diseases such as ataxia telangiectasia-like disorder (ATLD), Nijmegen breakage syndrome (NBS), NBS-like disorder (NBSLD) and certain types of cancers. Overall, deepening our understanding of disease-causing mutations of the MRN complex at the structural and biochemical level is foundational to the future aim of treating diseases associated with these aberrations. Full article
(This article belongs to the Special Issue Double-Strand DNA Break Repair and Human Disease)
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Open AccessArticle
Sustained Isometric Wrist Flexion and Extension Maximal Voluntary Contractions on Corticospinal Excitability to Forearm Muscles during Low-Intensity Hand-Gripping
Brain Sci. 2020, 10(7), 445; https://doi.org/10.3390/brainsci10070445 (registering DOI) - 13 Jul 2020
Abstract
The wrist extensors demonstrate an earlier fatigue onset than the wrist flexors. However, it is currently unclear whether fatigue induces unique changes in muscle activity or corticospinal excitability between these muscle groups. The purpose of this study was to examine how sustained isometric [...] Read more.
The wrist extensors demonstrate an earlier fatigue onset than the wrist flexors. However, it is currently unclear whether fatigue induces unique changes in muscle activity or corticospinal excitability between these muscle groups. The purpose of this study was to examine how sustained isometric wrist extension/flexion maximal voluntary contractions (MVCs) influence muscle activity and corticospinal excitability of the forearm. Corticospinal excitability to three wrist flexors and three wrist extensors were measured using motor evoked potentials (MEPs) elicited via transcranial magnetic stimulation. Responses were elicited while participants exerted 10% of their maximal handgrip force, before and after a sustained wrist flexion or extension MVC (performed on separate sessions). Post-fatigue measures were collected up to 10-min post-fatigue. Immediately post-fatigue, extensor muscle activity was significantly greater following the wrist flexion fatigue session, although corticospinal excitability (normalized to muscle activity) was greater on the wrist extension day. Responses were largely unchanged in the wrist flexors. However, for the flexor carpi ulnaris, normalized MEP amplitudes were significantly larger following wrist extension fatigue. These findings demonstrate that sustained isometric flexion/extension MVCs result in a complex reorganization of forearm muscle recruitment strategies during hand-gripping. Based on these findings, previously observed corticospinal behaviour following fatigue may not apply when the fatiguing task and measurement task are different. Full article
(This article belongs to the Special Issue Brain Plasticity and Motor Control—Series II)
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Open AccessArticle
A Study on the Deduction and Diffusion of Promising Artificial Intelligence Technology for Sustainable Industrial Development
Sustainability 2020, 12(14), 5609; https://doi.org/10.3390/su12145609 (registering DOI) - 13 Jul 2020
Abstract
Based on the rapid development of Information and Communication Technology (ICT), all industries are preparing for a paradigm shift as a result of the Fourth Industrial Revolution. Therefore, it is necessary to study the importance and diffusion of technology and, through this, the [...] Read more.
Based on the rapid development of Information and Communication Technology (ICT), all industries are preparing for a paradigm shift as a result of the Fourth Industrial Revolution. Therefore, it is necessary to study the importance and diffusion of technology and, through this, the development and direction of core technologies. Leading countries such as the United States and China are focusing on artificial intelligence (AI)’s great potential and are working to establish a strategy to preempt the continued superiority of national competitiveness through AI technology. This is because artificial intelligence technology can be applied to all industries, and it is expected to change the industrial structure and create various business models. This study analyzed the leading artificial intelligence technology to strengthen the market’s environment and industry competitiveness. We then analyzed the lifecycle of the technology and evaluated the direction of sustainable development in industry. This study collected and studied patents in the field of artificial intelligence from the US Patent Office, where technology-related patents are concentrated. All patents registered as artificial intelligence technology were analyzed by text mining, using the abstracts of each patent. The topic was extracted through topic modeling and defined as a detailed technique. Promising/mature skills were analyzed through a regression analysis of the extracted topics. In addition, the Bass model was applied to the promising technologies, and each technology was studied in terms of the technology lifecycle. Eleven topics were extracted via topic modeling. A regression analysis was conducted to identify the most promising/mature technology, and the results were analyzed with three promising technologies and five mature technologies. Promising technologies include Augmented Reality (AR)/Virtual Reality (VR), Image Recognition and Identification Technology. Mature technologies include pattern recognition, machine learning platforms, natural language processing, knowledge representation, optimization, and solving. This study conducts a quantitative analysis using patent data to derive promising technologies and then presents the objective results. In addition, this work then applies the Bass model to the promising artificial intelligence technology to evaluate the development potential and technology diffusion of each technology in terms of its growth cycle. Through this, the growth cycle of AI technology is analyzed in a complex manner, and this study then predicts the replacement timing between competing technologies. Full article
(This article belongs to the Section Economic and Business Aspects of Sustainability)
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Open AccessArticle
A Systematic Approach to Calculate Unit Emergy Values of Cement Manufacturing in China Using Consumption Quota of Dry and Wet Raw Materials
Buildings 2020, 10(7), 128; https://doi.org/10.3390/buildings10070128 (registering DOI) - 13 Jul 2020
Abstract
The Chinese cement industry produced 2150 million metric tons of cement in 2014, accounting for 58.1% of the world’s total. This industry has a hugely destructive effect on the environment owing to its pollution. The environmental impact of cement manufacturing is a major [...] Read more.
The Chinese cement industry produced 2150 million metric tons of cement in 2014, accounting for 58.1% of the world’s total. This industry has a hugely destructive effect on the environment owing to its pollution. The environmental impact of cement manufacturing is a major concern for China. Although researchers have attempted to estimate impacts using life cycle assessment approaches, it lacks the ability to provide a holistic evaluation of the impacts on the environment. Emergy analysis, through ecological accounting, offers environmental decision making using elaborate book keeping. In spite of the high environmental impact of the cement industry, there has only been a handful of research work done to compute the unit emergy values (UEVs) of cement manufacturing in China. A thorough study of existing UEVs of cement manufacturing in China showed pitfalls that may lead to inaccurate estimations if used in emergy analysis. There is a strong need for a new, updated UEV for cement manufacturing in China, particularly reflecting both the dry and wet raw materials in the manufacturing process. This paper develops a methodology to calculate the nonrenewable resources used in cement manufacturing, particularly using mainstream cement production line. Our systematic approach-based UEV estimates of cement manufacturing in China using the quota method are 2.56 × 1012 sej/kg (wet material) and 2.46 × 1012 sej/kg (dry material). Emergy indicators such as environmental loading ratios which were calculated at 2390 (wet material) and 2300 (dry material); emergy yield ratios at 15.7 and 15.8; and emergy sustainability indices at 0.0066 and 0.0069 for dry and wet materials used in cement manufacturing, respectively; these show the immense impact on the environment in China. Full article
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Open AccessArticle
Fabrication of Hollow Structures in Photodegradable Hydrogels Using a Multi-Photon Excitation Process for Blood Vessel Tissue Engineering
Micromachines 2020, 11(7), 679; https://doi.org/10.3390/mi11070679 (registering DOI) - 13 Jul 2020
Abstract
Engineered blood vessels generally recapitulate vascular function in vitro and can be utilized in drug discovery as a novel microphysiological system. Recently, various methods to fabricate vascular models in hydrogels have been reported to study the blood vessel functions in vitro; however, [...] Read more.
Engineered blood vessels generally recapitulate vascular function in vitro and can be utilized in drug discovery as a novel microphysiological system. Recently, various methods to fabricate vascular models in hydrogels have been reported to study the blood vessel functions in vitro; however, in general, it is difficult to fabricate hollow structures with a designed size and structure with a tens of micrometers scale for blood vessel tissue engineering. This study reports a method to fabricate the hollow structures in photodegradable hydrogels prepared in a microfluidic device. An infrared femtosecond pulsed laser, employed to induce photodegradation via multi-photon excitation, was scanned in the hydrogel in a program-controlled manner for fabricating the designed hollow structures. The photodegradable hydrogel was prepared by a crosslinking reaction between an azide-modified gelatin solution and a dibenzocyclooctyl-terminated photocleavable tetra-arm polyethylene glycol crosslinker solution. After assessing the composition of the photodegradable hydrogel in terms of swelling and cell adhesion, the hydrogel prepared in the microfluidic device was processed by laser scanning to fabricate linear and branched hollow structures present in it. We introduced a microsphere suspension into the fabricated structure in photodegradable hydrogels, and confirmed the fabrication of perfusable hollow structures of designed patterns via the multi-photon excitation process. Full article
(This article belongs to the Special Issue Cell Microarrays)
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Open AccessArticle
Early Arterial Intimal Thickening and Plaque Is Related with Treatment Regime and Cardiovascular Disease Risk Factors in Young Adults Following Childhood Hematopoietic Stem Cell Transplantation
J. Clin. Med. 2020, 9(7), 2208; https://doi.org/10.3390/jcm9072208 (registering DOI) - 13 Jul 2020
Abstract
The long-term vascular effects following childhood hematopoietic stem cell transplantation (HSCT) are not well characterized. We compared arterial wall morphology and function using very-high resolution ultrasound (25–55 MHz) in 62 patients following autologous (n = 19) or allogenic (n = 43) [...] Read more.
The long-term vascular effects following childhood hematopoietic stem cell transplantation (HSCT) are not well characterized. We compared arterial wall morphology and function using very-high resolution ultrasound (25–55 MHz) in 62 patients following autologous (n = 19) or allogenic (n = 43) HSCT for childhood malignancies and hematological disease (median age 25.9 years, IQR 21.1–30.1; median follow-up time 17.5 years IQR 14.1–23.0) with an age matched healthy control group (n = 44). Intima-media thickness of carotid (CIMT 0.49 ± 0.11 vs. 0.42 ± 0.06 mm, p < 0.001), brachial, femoral, radial arteries, and local carotid stiffness, but not adventitial thickness, were increased (p < 0.001). Diffuse intimal thickening (>0.06 mm) of femoral or radial arteries (n = 17) and subclinical carotid or femoral plaques (n = 18) were more common (p < 0.001). Radiation predicted plaques (p < 0.001) and local carotid stiffness (p < 0.001), but not intimal thickening. CIMT was predicted by age, BMI >30 kg/m2, hsCRP >2.5 mg/L, hypertension, HbA1c > 42 mmol/L, and cumulative anthracycline >150 mg/m2. Cumulative metabolic syndrome criteria and cardiovascular disease (CVD) risk factors were more common among HSCT and related with CIMT (p < 0.001), but CIMT was similar among controls and HSCT without CVD risk factors. Long-term childhood HSCT survivors show early arterial aging related with radiation, metabolic, and CVD risk factors. Prevention of risk factors could potentially decelerate early arterial wall thickening. Full article
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Open AccessArticle
Form Factors of an Economically Valuable Sal Tree (Shorea robusta) of Nepal
Forests 2020, 11(7), 754; https://doi.org/10.3390/f11070754 (registering DOI) - 13 Jul 2020
Abstract
The accurate prediction of the volume of standing trees is a prerequisite for planning and decision making in sustainable forest management. In Nepal, limited information on form factor (i.e. the ratio of the volume of a tree to the product of its basal [...] Read more.
The accurate prediction of the volume of standing trees is a prerequisite for planning and decision making in sustainable forest management. In Nepal, limited information on form factor (i.e. the ratio of the volume of a tree to the product of its basal area and height) is available for economically important tree species. Thus, current management plans consider a simple approximation for all species irrespective of their height and diameter, which hampers the estimation of a sustainable harvest rate. Therefore, this study elaborates the form factor for Sal (Shorea robusta), an economically valuable tree of Nepal based on a random selection of 100 individual trees representing a wide range of diameters between 10 and 100 cm. Diameter and bark thickness were measured at every 1-meter interval of the length of the stem and branches until the diameter reached 10 cm. The analysis allowed for the estimation of an average form factor for Sal wood with 0.407 over bark and 0.336 under bark, while the form factor for the stem was 0.335 over bark and 0.281 under bark. The results indicate an increasing form factor until 70 cm diameter and a decreasing value for larger diameters, because of the large crowns of the mature Sal trees. We conclude that the default form factor of Sal (0.5) used in management planning results in an overestimation of standing tree volume. Using form factor according to diameter classes will allow a more accurate prediction of the standing volume. Full article
(This article belongs to the Section Forest Ecology and Management)
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Open AccessCommunication
Efficacy of a Novel Metaldehyde Application Method to Control the Brown Garden Snail, Cornu aspersum (Helicidae), in South Africa
Insects 2020, 11(7), 437; https://doi.org/10.3390/insects11070437 (registering DOI) - 13 Jul 2020
Abstract
Baitchain is a novel molluscicide system that consists of metaldehyde pellets arranged on a cord and is designed to be tied around the base of tree trunks and act as a physical and chemical control method for molluscs. In this study, Baitchain is [...] Read more.
Baitchain is a novel molluscicide system that consists of metaldehyde pellets arranged on a cord and is designed to be tied around the base of tree trunks and act as a physical and chemical control method for molluscs. In this study, Baitchain is tested in a South African apple orchard and compared with traditional metaldehyde pellets (Sluggit) applied to the soil surface to determine the efficacy of the products against the brown garden snail, Cornu aspersum (Helicidae). The products were applied at two different concentrations, including 15 g/kg (Baitchain 15 and Sluggit 15) and 40 g/kg (Baitchain 40 and Sluggit 40) metaldehyde, and the products were either applied on their own, or in combination. Both treatments at 40 g/kg metaldehyde caused significant snail mortality when applied either on their own or in combination. However, significant mortality was also achieved by Baitchain 15 when applied on its own as well as in combination with Sluggit 15. The increased efficacy achieved by using Baitchain, even at the lower concentration, indicates that this novel method offers a viable physical and chemical control option for molluscs and could be incorporated as part of an integrated pest management strategy in South Africa, as well as other parts of the world. Full article
(This article belongs to the Special Issue Biology and Management of Slug and Snail Pests)
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Open AccessFeature PaperArticle
A Lattice Litany for Transition Metal Oxides
Condens. Matter 2020, 5(3), 46; https://doi.org/10.3390/condmat5030046 (registering DOI) - 13 Jul 2020
Abstract
In this tribute to K Alex Müller, I describe how his early insights have influenced future decades of research on perovskite ferroelectrics and more broadly transition metal oxides (TMOs) and related quantum materials. I use his influence on my own research journey to [...] Read more.
In this tribute to K Alex Müller, I describe how his early insights have influenced future decades of research on perovskite ferroelectrics and more broadly transition metal oxides (TMOs) and related quantum materials. I use his influence on my own research journey to discuss impacts in three areas: structural phase transitions, precursor structure, and quantum paraelectricity. I emphasize materials functionality in ground, metastable, and excited states arising from competitions among lattice, charge, and spin degrees of freedom, which results in highly tunable landscapes and complex networks of multiscale configurations controlling macroscopic functions. I discuss competitions between short- and long-range forces as particularly important in TMOs (and related materials classes) because of their localized and directional metal orbitals and the polarizable oxygen ions. I emphasize crucial consequences of elasticity and metal–oxygen charge transfer. Full article
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Open AccessArticle
Limited Agreement between Classifications of Diabetes and Prediabetes Resulting from the OGTT, Hemoglobin A1c, and Fasting Glucose Tests in 7412 U.S. Adults
J. Clin. Med. 2020, 9(7), 2207; https://doi.org/10.3390/jcm9072207 (registering DOI) - 13 Jul 2020
Abstract
This investigation was designed to determine the degree of concordance resulting from tests of fasting plasma glucose (FPG) and hemoglobin A1c (A1c) compared to the oral glucose tolerance test (OGTT) for detecting prediabetes and diabetes in undiagnosed adults. Another objective was to measure [...] Read more.
This investigation was designed to determine the degree of concordance resulting from tests of fasting plasma glucose (FPG) and hemoglobin A1c (A1c) compared to the oral glucose tolerance test (OGTT) for detecting prediabetes and diabetes in undiagnosed adults. Another objective was to measure concordance within subsamples of women and men, and within three age groups. Lastly, the value of combining the FPG and A1c for detecting diabetes was compared to the OGTT. A total of 7412 randomly selected adults from the National Health and Nutrition Examination Survey (NHANES) were included. With outcomes classified as normal, prediabetes, or diabetes, according to standard guidelines, overall test agreements were low. With an OGTT diagnosis of diabetes, concordance was only 34% for the A1c assessment and 44% for the FPG assay. Delimited to older adults, agreement between the OGTT and A1c was only 25%, and between the OGTT and FPG, concordance was only 33.5%. Given the large percentage of discordant results associated with the FPG and A1c, clinicians should be cautious about employing these tests as lone assessments. Using both the FPG and A1c helped with accurately diagnosing diabetes and normal glycemia, but not prediabetes. The OGTT is a good choice to reduce misdiagnosis. Full article
(This article belongs to the Section Epidemiology & Public Health)
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Open AccessArticle
Effects of Drought Stress on Some Agronomic and Morpho-Physiological Traits in Durum Wheat Genotypes
Sustainability 2020, 12(14), 5610; https://doi.org/10.3390/su12145610 (registering DOI) - 13 Jul 2020
Abstract
Durum wheat performance in the Mediterranean climate is limited when water scarcity occurs before and during anthesis. The present research was performed to determine the effect of drought stress on several physiological and agro-morphological traits in 17 durum wheat genotypes under two conditions [...] Read more.
Durum wheat performance in the Mediterranean climate is limited when water scarcity occurs before and during anthesis. The present research was performed to determine the effect of drought stress on several physiological and agro-morphological traits in 17 durum wheat genotypes under two conditions (control and drought) over two years. The results of analysis of variance indicated that the various durum wheat genotypes responded differently to drought stress. Drought stress significantly reduced the grain filling period, plant height, peduncle length, number of spikes per plot, number of grains per spike, thousand grains weight, grain yield, biomass, and harvest index in all genotypes compared to the control condition. The heatmap-based correlation analysis indicated that grain yield was positively and significantly associated with phenological characters (days to heading, days to physiological maturity, and grain filling period), as well as number of spikes per plant, biomass, and harvest index under drought conditions. The yield-based drought and susceptible indices revealed that stress tolerance index (STI), geometric mean productivity (GMP), mean productivity (MP), and harmonic mean (HM) were positively and significantly correlated with grain yields in both conditions. Based on the average of the sum of ranks across all indices and a three-dimensional plot, two genotypes (G9 and G12) along with the control variety (G1) were identified as the most tolerant genotypes. Among the investigated genotypes, the new breeding genotype G12 showed a high drought tolerance and yield performance under both conditions. Hence, this genotype can be a candidate for further multi-years and locations test as recommended for cultivation under rainfed conditions in arid and semi-arid regions. Full article
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Open AccessArticle
Automatic Segmentation and Classification of Heart Sounds Using Modified Empirical Wavelet Transform and Power Features
Appl. Sci. 2020, 10(14), 4791; https://doi.org/10.3390/app10144791 (registering DOI) - 13 Jul 2020
Abstract
A system for the automatic classification of cardiac sounds can be of great help for doctors in the diagnosis of cardiac diseases. Generally speaking, the main stages of such systems are (i) the pre-processing of the heart sound signal, (ii) the segmentation of [...] Read more.
A system for the automatic classification of cardiac sounds can be of great help for doctors in the diagnosis of cardiac diseases. Generally speaking, the main stages of such systems are (i) the pre-processing of the heart sound signal, (ii) the segmentation of the cardiac cycles, (iii) feature extraction and (iv) classification. In this paper, we propose methods for each of these stages. The modified empirical wavelet transform (EWT) and the normalized Shannon average energy are used in pre-processing and automatic segmentation to identify the systolic and diastolic intervals in a heart sound recording; then, six power characteristics are extracted (three for the systole and three for the diastole)—the motivation behind using power features is to achieve a low computational cost to facilitate eventual real-time implementations. Finally, different models of machine learning (support vector machine (SVM), k-nearest neighbor (KNN), random forest and multilayer perceptron) are used to determine the classifier with the best performance. The automatic segmentation method was tested with the heart sounds from the Pascal Challenge database. The results indicated an error (computed as the sum of the differences between manual segmentation labels from the database and the segmentation labels obtained by the proposed algorithm) of 843,440.8 for dataset A and 17,074.1 for dataset B, which are better values than those reported with the state-of-the-art methods. For automatic classification, 805 sample recordings from different databases were used. The best accuracy result was 99.26% using the KNN classifier, with a specificity of 100% and a sensitivity of 98.57%. These results compare favorably with similar works using the state-of-the-art methods. Full article
(This article belongs to the Special Issue Signal Processing and Machine Learning for Biomedical Data)
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Open AccessArticle
A Step Forward to the Characterization of Secondary Effluents to Predict Membrane Fouling in a Subsequent Ultrafiltration
Water 2020, 12(7), 1975; https://doi.org/10.3390/w12071975 (registering DOI) - 13 Jul 2020
Abstract
Nowadays, wastewater reuse in Mediterranean countries is necessary to cover the water demand. This contributes to the protection of the environment and encourages the circular economy. Due to increasingly strict regulation, the secondary effluent of a wastewater treatment plant requires further (tertiary) treatment [...] Read more.
Nowadays, wastewater reuse in Mediterranean countries is necessary to cover the water demand. This contributes to the protection of the environment and encourages the circular economy. Due to increasingly strict regulation, the secondary effluent of a wastewater treatment plant requires further (tertiary) treatment to reach enough quality for its reuse in agriculture. Ultrafiltration is a membrane technique suitable for tertiary treatment. However, the most important drawback of ultrafiltration is membrane fouling. The aim of this work is to predict membrane fouling and ultrafiltered wastewater permeate quality for a particular membrane, using the information given by an exhaustive secondary effluent characterization. For this, ultrafiltration of real and simulated wastewaters and of their components after fractionation has been performed. In order to better characterize the secondary effluent, resin fractionation and further membrane ultrafiltration of the generated fractions and wastewater were performed. The results indicated that hydrophobic substances were lower than hydrophilic ones in the secondary effluent. Supelite DAX-8, Amberlite XAD-4 and Amberlite IRA-958 resins were found not to be specific for humic acids, proteins and carbohydrates, which are the main components of the effluent organic matter. Two models have been performed using statistics (partial least squares, PLS) and an artificial neural network (ANN), respectively. The results showed that the ANN model predicted permeate quality and membrane fouling with higher accuracy than PLS. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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Open AccessArticle
Performance of an Adsorptive Heat-Moisture Regenerator Based on Silica Gel–Sodium Sulphate
Sustainability 2020, 12(14), 5611; https://doi.org/10.3390/su12145611 (registering DOI) - 13 Jul 2020
Abstract
The performance of an adsorptive heat-moisture regenerator based on a silica gel–sodium sulphate composite adsorbent was studied. The correlation between the adsorbent composition and structural characteristics of the laboratory-scale device was investigated. An algorithm for the calculation of the efficiency factors of the [...] Read more.
The performance of an adsorptive heat-moisture regenerator based on a silica gel–sodium sulphate composite adsorbent was studied. The correlation between the adsorbent composition and structural characteristics of the laboratory-scale device was investigated. An algorithm for the calculation of the efficiency factors of the adsorptive regenerator was further developed. The suggested algorithm calculates the operational parameters, including the temperatures, humidities and volumetric flows of internal and external air, and estimates the regenerator’s performance via temperature and moisture efficiency factors, total adsorption and time needed to achieve maximum adsorption, air pressure loss and fan power input. The validity of the calculation results obtained using the proposed algorithm was confirmed experimentally. Temperature efficiency factor, air pressure loss and fan power consumption are crucial parameters for the estimation of the optimal operating regime of an adsorptive heat-moisture regenerator. The correlation between meteorological conditions and efficiency factors was assessed and applied in a simulation of residential house-scale air conditioning unit operation. Maximal values of temperature efficiency factor were found at internal and external air temperatures of 15 to 20 °C and −5 to 0 °C, respectively. Moisture efficiency factors were observed to reach their maximum at the absolute humidities of external and internal air of 4.0 to 5.0 g/m3 and 2.75 to 3.0 g/m3, respectively. The fan power consumption of the adsorptive heat-moisture regenerator was found to be comparable to or even lower than that of commercial air conditioning units used in comparably voluminous interiors. Full article
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Open AccessArticle
Atypical Endometrial Hyperplasia and Unexpected Cancers at Final Histology: A Study on Endometrial Sampling Methods and Risk Factors
Diagnostics 2020, 10(7), 474; https://doi.org/10.3390/diagnostics10070474 (registering DOI) - 13 Jul 2020
Abstract
Background: Up to 40% of women with atypical endometrial hyperplasia (AEH) can reveal endometrial cancer (EC) at hysterectomy. The pre-operative endometrial sampling method (ESM) and some independent cancer predictors may affect this outcome. The present study aimed to compare the rate of EC [...] Read more.
Background: Up to 40% of women with atypical endometrial hyperplasia (AEH) can reveal endometrial cancer (EC) at hysterectomy. The pre-operative endometrial sampling method (ESM) and some independent cancer predictors may affect this outcome. The present study aimed to compare the rate of EC at hysterectomy in women with AEH undergoing dilation and curettage (D&C), hysteroscopically-guided biopsy (HSC-bio), or hysteroscopic endometrial resection (HSC-res). The secondary outcome was to compare the reliability of ESMs in women showing independent variables associated with EC. Methods: Two-hundred-and-eight consecutive women with AEH and undergoing hysterectomy between January 2000 and December 2017 were analyzed retrospectively. Based on pre- and post-test probability analysis for EC, three ESMs were compared: D&C, HSC-bio, and HSC-res. Univariate and multivariate analyses were performed to assess risk factors predicting cancer on final histology. Finally, the patient’s characteristics were compared between the three ESM groups. Results: D&C and HSC-bio included 75 women in each group, while HSC-res included 58 women. Forty-nine women (23.6%) revealed cancer at hysterectomy (pre-test probability). Post-test probability analysis showed that HSC-res had the lowest percentage of EC underestimation: HSC-res = 11.6%; HSC-bio = 19.5%; D&C = 35.3%. Patient characteristics showed no significant differences between the three ESMs. Multivariate analysis showed that body mass index ≥40 (Odds Ratio (OR) = 19.75; Confidence Intervals (CI) 2.193–177.829), and age (criterion > 60 years) (OR = 1.055, CI 1.002–1.111) associated significantly with EC. In women with one or both risk factors, post-test probability analysis showed that HSC-res was the only method with a lower EC rate at hysterectomy compared to a pre-test probability of 44.2%: HSC-res = 19.96%; HSC-bio = 53.81%; D&C = 63.12%. Conclusions: HSC-res provided the lowest rate of EC underestimation in AEH, also in women showing EC predictors. These data may be considered for better diagnostic and therapeutic planning of AEH. Full article
(This article belongs to the Section Pathology and Molecular Diagnostics)

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