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Open AccessEditorial
Sentiment Analysis for Social Media
Appl. Sci. 2019, 9(23), 5037; https://doi.org/10.3390/app9235037 (registering DOI) - 22 Nov 2019
Abstract
Sentiment analysis has become a key technology to gain insight from social networks. The field has reached a level of maturity that paves the way for its exploitation in many different fields such as marketing, health, banking or politics. The latest technological advancements, [...] Read more.
Sentiment analysis has become a key technology to gain insight from social networks. The field has reached a level of maturity that paves the way for its exploitation in many different fields such as marketing, health, banking or politics. The latest technological advancements, such as deep learning techniques, have solved some of the traditional challenges in the area caused by the scarcity of lexical resources. In this Special Issue, different approaches that advance this discipline are presented. The contributed articles belong to two broad groups: technological contributions and applications. Full article
(This article belongs to the Special Issue Sentiment Analysis for Social Media)
Open AccessArticle
Glutathione Deficiency and Alterations in the Sulfur Amino Acid Homeostasis during Early Postnatal Development as Potential Triggering Factors for Schizophrenia-Like Behavior in Adult Rats
Molecules 2019, 24(23), 4253; https://doi.org/10.3390/molecules24234253 (registering DOI) - 22 Nov 2019
Abstract
Impaired glutathione (GSH) synthesis and dopaminergic transmission are important factors in the pathophysiology of schizophrenia. Our research aimed to assess the effects of l-buthionine-(S,R)-sulfoximine (BSO), a GSH synthesis inhibitor, and GBR 12909, a dopamine reuptake inhibitor, administered alone [...] Read more.
Impaired glutathione (GSH) synthesis and dopaminergic transmission are important factors in the pathophysiology of schizophrenia. Our research aimed to assess the effects of l-buthionine-(S,R)-sulfoximine (BSO), a GSH synthesis inhibitor, and GBR 12909, a dopamine reuptake inhibitor, administered alone or in combination, to Sprague–Dawley rats during early postnatal development (p5–p16), on the levels of GSH, sulfur amino acids, global DNA methylation, and schizophrenia-like behavior. GSH, methionine (Met), homocysteine (Hcy), and cysteine (Cys) contents were determined in the liver, kidney, and in the prefrontal cortex (PFC) and hippocampus (HIP) of 16-day-old rats. DNA methylation in the PFC and HIP and schizophrenia-like behavior were assessed in adulthood (p90–p93). BSO caused the tissue-dependent decreases in GSH content and alterations in Met, Hcy, and Cys levels in the peripheral tissues and in the PFC and HIP. The changes in these parameters were accompanied by alterations in the global DNA methylation in the studied brain structures. Parallel to changes in the global DNA methylation, deficits in the social behaviors and cognitive functions were observed in adulthood. Only BSO + GBR 12909-treated rats exhibited behavioral alterations resembling positive symptoms in schizophrenia patients. Our results suggest the usefulness of this neurodevelopmental model for research on the pathomechanism of schizophrenia. Full article
(This article belongs to the Special Issue Sulfur Compounds and Human Health)
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Open AccessArticle
Development of a Model Test System for a Piston Ring/Cylinder Liner-Contact with Focus on Near-to-Application Seizure Behaviour
Lubricants 2019, 7(12), 104; https://doi.org/10.3390/lubricants7120104 (registering DOI) - 22 Nov 2019
Abstract
Physical simulations of tribo contacts in internal combustion engines can act as a supporting tool to match upcoming guidelines and emission restrictions. In particular, the scuffing resistance of the contact between the piston ring and cylinder liner suffers under decreasing oil viscosity and [...] Read more.
Physical simulations of tribo contacts in internal combustion engines can act as a supporting tool to match upcoming guidelines and emission restrictions. In particular, the scuffing resistance of the contact between the piston ring and cylinder liner suffers under decreasing oil viscosity and limitation of antiwear additives. This paper aims to provide an experimental method to simulate the scuffing of the piston ring/cylinder liner-contact and to validate this method with real engine parts and the literature from engine tests. The experimental methodology uses a linear tribometer TE77 to test specimens from original piston rings and liners under reciprocating motion. Additionally, the ring specimen is given the opportunity to perform secondary movements (ring twisting, ring turning) and to run under deficient lubrication conditions similar to the engine. A specially designed test strategy enables the reproducible creation of seizure of the tribosystem. The seizure resistance of two engine oils, tested for validation, correlates with the known engine performance. Therefore, the model test system can be seen as a reproducible tool for simulating seizure of a ring/liner-system, showing similar trends and wear mechanisms as in an engine. Surface analysis depicts similarities between the scuffed surfaces of an engine and the model and discusses the origin of seizure based on the model specimens together with the relevant literature. Full article
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Open AccessFeature PaperArticle
Lattice Boltzmann Simulation on Droplet Flow through 3D Metal Foam
Processes 2019, 7(12), 877; https://doi.org/10.3390/pr7120877 (registering DOI) - 22 Nov 2019
Abstract
The hydrodynamics of droplets passing through metal foam is investigated using the lattice Boltzmann method (LBM). The accurate 3D porous structure for the simulation is generated by X-ray micro-computed tomography. The simulated results are in good agreement with the experimental ones using high-speed [...] Read more.
The hydrodynamics of droplets passing through metal foam is investigated using the lattice Boltzmann method (LBM). The accurate 3D porous structure for the simulation is generated by X-ray micro-computed tomography. The simulated results are in good agreement with the experimental ones using high-speed video. The simulated results show that for droplets passing metal foam, there is a critical capillary number, Cac (around 0.061), above which the droplet continues to deform until it breaks up. The simulated results show that the capillary number, droplet size, pores diameter, and thickness of metal foam have the significant effect of droplets deforming and breaking up when the droplets pass through the metal foam. To avoid the calescence of two droplets at the inlet zone of the metal foam, the distance between droplets should be larger than three times the diameter of the droplet. Full article
(This article belongs to the Special Issue Smart Flow Control Processes in Micro Scale)
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Open AccessArticle
The Good, the Bad, and the Ethical Implications of Bridging Blockchain and Multi-Agent Systems
Information 2019, 10(12), 363; https://doi.org/10.3390/info10120363 (registering DOI) - 22 Nov 2019
Abstract
The agent based approach is a well established methodology to model distributed intelligent systems. Multi-Agent Systems (MAS) are increasingly employed in applications dealing with safety and information critical tasks (e.g., in eHealth, financial, and energy domains). Therefore, transparency and the trustworthiness of the [...] Read more.
The agent based approach is a well established methodology to model distributed intelligent systems. Multi-Agent Systems (MAS) are increasingly employed in applications dealing with safety and information critical tasks (e.g., in eHealth, financial, and energy domains). Therefore, transparency and the trustworthiness of the agents and their behaviors must be enforced. For example, employing reputation based mechanisms can promote the development of trust. Nevertheless, besides recent early stage studies, the existing methods and systems are still unable to guarantee the desired accountability and transparency adequately. In line with the recent trends, we advocate that combining blockchain technology (BCT) and MAS can achieve the distribution of the trust, removing the need for trusted third parties (TTP), potential single points of failure. This paper elaborates on the notions of trust, BCT, MAS, and their integration. Furthermore, to attain a trusted environment, this manuscript details the design and implementation of a system reconciling MAS (based on the Java Agent DEvelopment Framework (JADE)) and BTC (based on Hyperledger Fabric). In particular, the agents’ interactions, computation, tracking the reputation, and possible policies for disagreement-management are implemented via smart contracts and stored on an immutable distributed ledger. The results obtained by the presented system and similar solutions are also discussed. Finally, ethical implications (i.e., opportunities and challenges) are elaborated before concluding the paper. Full article
(This article belongs to the Special Issue Blockchain Technologies for Multi-Agent Systems)
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Open AccessArticle
Zero-Shot Deep Learning for Media Mining: Person Spotting and Face Clustering in Video Big Data
Electronics 2019, 8(12), 1394; https://doi.org/10.3390/electronics8121394 (registering DOI) - 22 Nov 2019
Abstract
The analysis of frame sequences in talk show videos, which is necessary for media mining and television production, requires significant manual efforts and is a very time-consuming process. Given the vast amount of unlabeled face frames from talk show videos, we address and [...] Read more.
The analysis of frame sequences in talk show videos, which is necessary for media mining and television production, requires significant manual efforts and is a very time-consuming process. Given the vast amount of unlabeled face frames from talk show videos, we address and propose a solution to the problem of recognizing and clustering faces. In this paper, we propose a TV media mining system that is based on a deep convolutional neural network approach, which has been trained with a triplet loss minimization method. The main function of the proposed system is the indexing and clustering of video data for achieving an effective media production analysis of individuals in talk show videos and rapidly identifying a specific individual in video data in real-time processing. Our system uses several face datasets from Labeled Faces in the Wild (LFW), which is a collection of unlabeled web face images, as well as YouTube Faces and talk show faces datasets. In the recognition (person spotting) task, our system achieves an F-measure of 0.996 for the collection of unlabeled web face images dataset and an F-measure of 0.972 for the talk show faces dataset. In the clustering task, our system achieves an F-measure of 0.764 and 0.935 for the YouTube Faces database and the LFW dataset, respectively, while achieving an F-measure of 0.832 for the talk show faces dataset, an improvement of 5.4%, 6.5%, and 8.2% over the previous methods. Full article
(This article belongs to the Section Artificial Intelligence)
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Open AccessArticle
Predicting Adolescent Adjustment and Well-Being: The Interplay between Socio-Emotional and Personal Factors
Int. J. Environ. Res. Public Health 2019, 16(23), 4650; https://doi.org/10.3390/ijerph16234650 (registering DOI) - 22 Nov 2019
Abstract
Social and emotional factors such as emotional competence and self-esteem are protective factors that promote adolescent mental health and well-being. In this paper, we will examine the combined contribution of these socio-emotional factors in addition to personal factors, in the prediction of psychological [...] Read more.
Social and emotional factors such as emotional competence and self-esteem are protective factors that promote adolescent mental health and well-being. In this paper, we will examine the combined contribution of these socio-emotional factors in addition to personal factors, in the prediction of psychological adjustment and subjective well-being in adolescence. The study included 840 adolescents aged between 12 and 16 years old (M = 13.37, SD = 1.16, 51.4% girls). We measured personal variables (sex, age, number of siblings), socio-emotional variables (emotional competence and self-esteem), psychological adjustment (emotional and behavioural problems) and subjective well-being (life satisfaction and affect balance). Besides descriptive analysis and Pearson bivariate correlations, two different methodologies were performed, including hierarchical regression models and a fuzzy-set qualitative comparative analysis (fsQCA). The results show that emotional competence is a protective factor for optimal adjustment and well-being, and suggest that self-esteem reinforces this relation. Different patterns were observed for female and male adolescents of different ages and with different family backgrounds. The practical implications of our findings for intervention programs have been discussed. Full article
(This article belongs to the Special Issue Emotional and Behavioural Adjustment in Adolescence)
Open AccessArticle
Experimental Validation of a Reliable Palmprint Recognition System Based on 2D Ultrasound Images
Electronics 2019, 8(12), 1393; https://doi.org/10.3390/electronics8121393 (registering DOI) - 22 Nov 2019
Abstract
Ultrasound has been trialed in biometric recognition systems for many years, and at present different types of ultrasound fingerprint readers are being produced and integrated in portable devices. An important merit of the ultrasound is its ability to image the internal structure of [...] Read more.
Ultrasound has been trialed in biometric recognition systems for many years, and at present different types of ultrasound fingerprint readers are being produced and integrated in portable devices. An important merit of the ultrasound is its ability to image the internal structure of the hand, which can guarantee improved recognition rates and resistance to spoofing attacks. In addition, ambient noise like changes of illumination, humidity, or temperature, as well as oil or ink stains on the skin do not affect the ultrasound image. In this work, a palmprint recognition system based on ultrasound images is proposed and experimentally validated. The system uses a gel pad to obtain acoustic coupling between the ultrasound probe and the user’s hand. The collected volumetric image is processed to extract 2D palmprints at various under-skin depths. Features are extracted from one of these 2D palmprints using a line-based procedure. Recognition performances of the proposed system were evaluated by performing both verification and identification experiments on a home-made database containing 281 samples collected from 32 different volunteers. An equal error rate of 0.38% and an identification rate of 100% were achieved. These results are very satisfactory, even if obtained with a relatively small database. A discussion on the causes of bad acquisitions is also presented, and a possible solution to further optimize the acquisition system is suggested. Full article
(This article belongs to the Special Issue Recent Advances in Biometrics and its Applications)
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Open AccessCommunication
Synthesis and Characterization of Unsymmetrical Double-Decker Siloxane (Basket Cage)
Molecules 2019, 24(23), 4252; https://doi.org/10.3390/molecules24234252 (registering DOI) - 22 Nov 2019
Abstract
The one-pot synthesis of an unsymmetrical double-decker siloxane with a novel structure via the reaction of double-decker tetrasodiumsilanolate with 1 equiv. of dichlorotetraphenyldisiloxane in the presence of an acid is reported herein for the first time. The target compound bearing all phenyl substituents [...] Read more.
The one-pot synthesis of an unsymmetrical double-decker siloxane with a novel structure via the reaction of double-decker tetrasodiumsilanolate with 1 equiv. of dichlorotetraphenyldisiloxane in the presence of an acid is reported herein for the first time. The target compound bearing all phenyl substituents on the unsymmetrical siloxane structure was successfully obtained, as confirmed by 1H-NMR, 13C-NMR, 29Si-NMR, IR, MALDI-TOF, and X-ray crystallography analyses. Additionally, the thermal properties of the product were evaluated by TG/DTA and compared with those of other siloxane cage compounds. Full article
(This article belongs to the Special Issue Synthesis of Functional Silicon Compounds)
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Open AccessArticle
Myoinvasive Pattern as a Prognostic Marker in Low-Grade, Early-Stage Endometrioid Endometrial Carcinoma
Cancers 2019, 11(12), 1845; https://doi.org/10.3390/cancers11121845 (registering DOI) - 22 Nov 2019
Abstract
Low-grade and early Federation for Gynecology and Obstetrics (FIGO) stage endometrioid endometrial carcinomas (EEC) have an excellent prognosis. However, approximately 10% of patients develop recurrence, which cannot be correctly predicted at diagnosis. We evaluated myoinvasive patterns as a prognostic factor of relapse in [...] Read more.
Low-grade and early Federation for Gynecology and Obstetrics (FIGO) stage endometrioid endometrial carcinomas (EEC) have an excellent prognosis. However, approximately 10% of patients develop recurrence, which cannot be correctly predicted at diagnosis. We evaluated myoinvasive patterns as a prognostic factor of relapse in low-grade, early-stage EEC. Two-hundred and fifty-eight cases were selected according to the following inclusion criteria: (i) endometrioid endometrial carcinomas, (ii) grade 1 or 2 with (iii) FIGO stage I or II, and (iv) clinical follow-up. Slides were reviewed to annotate the myoinvasive pattern present in each case (infiltrative glands, microcystic, elongated and fragmented –MELF-, broad front, adenomyosis-like and adenoma malignum). Microsatellite instability was studied by immunoexpression of mismatch repair proteins (MLH1, PMS2, MSH2, and MSH6). There were 29 recurrences (11.2%) among the 258 cases analysed. A predominant broad front myoinvasive pattern was significantly associated with tumour relapse (p = 0.003). The presence of a pattern of infiltrative glands (p = 0.001) and microsatellite instability (p = 0.004) were associated with lower disease-free survival, without having an impact on overall survival. Our observations suggest the potential value of the pattern of myoinvasion as a prognostic factor in low-grade, early-stage endometrioid endometrial carcinoma. Full article
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Open AccessReview
Mutations in Splicing Factor Genes in Myeloid Malignancies: Significance and Impact on Clinical Features
Cancers 2019, 11(12), 1844; https://doi.org/10.3390/cancers11121844 (registering DOI) - 22 Nov 2019
Abstract
Components of the pre-messenger RNA splicing machinery are frequently mutated in myeloid malignancies. Mutations in LUC7L2, PRPF8, SF3B1, SRSF2, U2AF1, and ZRSR2 genes occur at various frequencies ranging between 40% and 85% in different subtypes of myelodysplastic syndrome (MDS) and [...] Read more.
Components of the pre-messenger RNA splicing machinery are frequently mutated in myeloid malignancies. Mutations in LUC7L2, PRPF8, SF3B1, SRSF2, U2AF1, and ZRSR2 genes occur at various frequencies ranging between 40% and 85% in different subtypes of myelodysplastic syndrome (MDS) and 5% and 10% of acute myeloid leukemia (AML) and myeloproliferative neoplasms (MPNs). In some instances, splicing factor (SF) mutations have provided diagnostic utility and information on clinical outcomes as exemplified by SF3B1 mutations associated with increased ring sideroblasts (RS) in MDS-RS or MDS/MPN-RS with thrombocytosis. SF3B1 mutations are associated with better survival outcomes, while SRSF2 mutations are associated with a shorter survival time and increased AML progression, and U2AF1 mutations with a lower remission rate and shorter survival time. Beside the presence of mutations, transcriptomics technologies have shown that one third of genes in AML patients are differentially expressed, leading to altered transcript stability, interruption of protein function, and improper translation compared to those of healthy individuals. The detection of SF mutations demonstrates the importance of splicing abnormalities in the hematopoiesis of MDS and AML patients given the fact that abnormal splicing regulates the function of several transcriptional factors (PU.1, RUNX1, etc.) crucial in hematopoietic function. This review provides a summary of the significance of the most frequently mutated SF genes in myeloid malignancies and an update on novel targeted therapies in experimental and clinical trial stages. Full article
(This article belongs to the Special Issue Acute Myeloid Leukemia)
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Open AccessReview
A Review of Regional and Global Gridded Forest Biomass Datasets
Remote Sens. 2019, 11(23), 2744; https://doi.org/10.3390/rs11232744 (registering DOI) - 22 Nov 2019
Abstract
Forest biomass quantification is essential to the global carbon cycle and climate studies. Many studies have estimated forest biomass from a variety of data sources, and consequently generated some regional and global maps. However, these forest biomass maps are not well known and [...] Read more.
Forest biomass quantification is essential to the global carbon cycle and climate studies. Many studies have estimated forest biomass from a variety of data sources, and consequently generated some regional and global maps. However, these forest biomass maps are not well known and evaluated. In this paper, we reviewed an extensive list of currently available forest biomass maps. For each map, we briefly introduced the data sources, the algorithms used, and the associated uncertainties. Large-scale biomass datasets were compared across Europe, the conterminous United States, Southeast Asia, tropical Africa and South America. Results showed that these forest biomass datasets were almost entirely inconsistent, particularly in woody savannas and savannas across these regions. The uncertainties in biomass maps could be from a variety of sources including the chosen allometric equations used to calculate field data, the choice and quality of remotely sensed data, as well as the algorithms to map forest biomass or extrapolation techniques, but these uncertainties have not been fully quantified. We suggested the future directions for generating more accurate large-scale forest biomass maps should concentrate on the compilation of field biomass data, novel approaches of forest biomass mapping, and comprehensively addressing the accuracy of generated biomass maps. Full article
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Open AccessArticle
Tumour-Secreted Protein S (ProS1) Activates a Tyro3-Erk Signalling Axis and Protects Cancer Cells from Apoptosis
Cancers 2019, 11(12), 1843; https://doi.org/10.3390/cancers11121843 (registering DOI) - 22 Nov 2019
Abstract
The TAM subfamily (Tyro3, Axl, MerTK) of receptor tyrosine kinases are implicated in several cancers, where they have been shown to support primary tumorigenesis as well as secondary resistance to cancer therapies. Relatively little is known about the oncogenic role of Tyro3, including [...] Read more.
The TAM subfamily (Tyro3, Axl, MerTK) of receptor tyrosine kinases are implicated in several cancers, where they have been shown to support primary tumorigenesis as well as secondary resistance to cancer therapies. Relatively little is known about the oncogenic role of Tyro3, including its ligand selectivity and signalling in cancer cells. Tyro3 showed widespread protein and mRNA expression in a variety of human cancer cell lines. In SCC-25 head and neck cancer cells expressing both Tyro3 and Axl, Western blotting showed that both natural TAM ligands ProS1 and Gas6 rapidly stimulated Tyro3 and Erk kinase phosphorylation, with ProS1 eliciting a greater effect. In contrast, Gas6 was the sole stimulator of Axl and Akt kinase phosphorylation. In MGH-U3 bladder cancer cells, which express Tyro3 alone, ProS1 was again the stronger stimulator of Tyro3 and Erk stimulation but additionally stimulated Akt phosphorylation. Conditioned medium from ProS1-secreting 786-0 kidney cancer cells replicated the kinase activation effects of recombinant ProS1 in SCC-25 cells, with specificity confirmed by ProS1 ligand traps and warfarin. In addition, ProS1 protected cancer cells from acute apoptosis induced by staurosporine, as well as additionally, long-term serum starvation-induced apoptosis in MGH-U3 cells (Tyro3 only), which reflects its additional coupling to Akt signalling in these cells. In conclusion, we have shown that ProS1 is a tumour-derived functional ligand for Tyro3 that supports cancer cell survival. Furthermore, the ProS1-Tyro3 interaction is primarily coupled to Erk signalling although it displays signalling diversity dependent upon its representative expression as a TAM receptor in tumour cells. Full article
(This article belongs to the collection Kinases and Cancer)
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Open AccessArticle
Improving the Light-Induced Spin Transition Efficiency in Ni(II)-Based Macrocyclic-Ligand Complexes
Molecules 2019, 24(23), 4249; https://doi.org/10.3390/molecules24234249 (registering DOI) - 22 Nov 2019
Abstract
The structural stability and photoabsorption properties of Ni(II)-based metal-organic complexes with octahedral coordination having different planar ligand ring structures were investigated employing density functional theory (DFT) and its time-dependent extension (TD-DFT) considering the M06 exchange-correlation functional and the Def2-TZVP basis set. The results [...] Read more.
The structural stability and photoabsorption properties of Ni(II)-based metal-organic complexes with octahedral coordination having different planar ligand ring structures were investigated employing density functional theory (DFT) and its time-dependent extension (TD-DFT) considering the M06 exchange-correlation functional and the Def2-TZVP basis set. The results showed that the molecular composition of different planar cyclic ligand structures had significant influences on the structural stability and photoabsorption properties of metal-organic complexes. Only those planar ligands that contained aromatic rings met the basic criteria (thermal stability, structural reversibility, and appropriate excitation frequency domain) for light-induced excited spin state trapping, but their spin transition efficiencies were very different. While, in all three aromatic cases, the singlet electronic excitations induced charge distribution that could help in the singlet-to-triplet spin transition, and triplet excitations, which could assist in the backward (triplet-to-singlet) spin transition, was found only for one complex. Full article
(This article belongs to the Section Computational and Theoretical Chemistry)
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