bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual-Input Slope Seeking Control of Continuous Micro-Algae Cultures with Experimental Validation
Authors: Feudjio Letchindjio Christian , Zamudio Lara Jesús , Dewasme Laurent , Hernández Escoto Héctor , Vande Wouwer Alain
Published: August 2021

This paper investigates the application of adaptive slope-seeking strategies to dual-input single output dynamic processes. While the classical objective of extremum seeking control is to drive a process performance index to its optimum, this paper also considers slope seeking, which allows driving the performance index to a desired level (which is thus sub-optimal). Moreover, the consideration of more than one input signal allows minimizing the input energy thanks to the degrees of freedom offered by the additional inputs. The actual process is assumed to be locally approachable by a Hammerstein model, combining a nonlinear static map with a linear dynamic model. The proposed strategy is based on the interplay of three components: (i) a recursive estimation algorithm providing the model parameters and the performance index gradient, (ii) a slope generator using the static map parameter estimates to convert the performance index setpoint into slope setpoints, and (iii) an adaptive controller driving the process to the desired setpoint. The performance of the slope strategy is assessed in simulation in an application example related to lipid productivity optimization in continuous cultures of micro-algae by acting on both the incident light intensity and the dilution rate. It is also validated in experimental studies where biomass production in a continuous photo-bioreactor is targeted.
Continuous-Time Perfect Control Algorithm—A State Feedback Approach
Authors: Krok Marek , Hunek Wojciech P. , Majewski Paweł
Published: August 2021

In this paper, a new approach to the continuous-time perfect control algorithm is given. Focusing on the output derivative, it is shown that the discussed control law can effectively be implemented in terms of state-feedback scenarios. Moreover, the application of nonunique matrix inverses is also taken into consideration during the perfect control design process. Simulation examples given within this work allow us to showcase the main properties obtained for continuous-time perfect control closed-loop plants.
The Effect of Hot Isostatic Pressing on Surface Integrity, Microstructure and Strength of Hybrid Metal Injection Moulding, and Laser-Based Powder Bed Fusion Stainless-Steel Components
Authors: Mehmeti Aldi , Lynch Donal , Penchev Pavel , Martinez Ramos Rafael , Vincent Denis , Maurath Johannes , Wimpenny David Ian , Essa Khamis , Dimov Stefan
Published: August 2021

Hybrid manufacture of components by combining capabilities of replication and additive manufacturing processes offer a flexible and sustainable route for producing cost-effectively small batches of metal parts. At present, there are open issues related to surface integrity and performance of such parts, especially when utilising them in safety critical applications. The research presented in this paper investigates the ductility amplification of hybrid components produced using metal injection moulding to preform and then build on them customisable sections by laser-based powder bed fusion. The properties of such hybrid components are studied and optimised through the use of non-conventional post treatment techniques. In particular, hot isostatic pressing (HIP) is employed to improve mechanical strength and to produce hybrid components that have consistent properties across batches and throughout the samples, minimising microstructural heterogeneities between fabrication processes. Thus, the investigated post-processing method can offer an extended service life of hybrid components, especially when operating under severe conditions. The optimised post treatment was found to increase the hybrid components’ strength compared to as-built ones by 68% and ~11% in yield strength (YS) and ultimate tensile strength (UTS), respectively. Subsequently, leading to a great pitting resistance, thus, making HIP samples suitable for corrosive environments. The advantages of the HIP treatments in comparison to the conventional heat treatment of hybrid components are discussed and also some potential application areas are proposed.
Performance of a Ductile Hybrid Post-Tensioned Beam-to-Column Connection for Precast Concrete Frames under Seismic Loads: A Review
Authors: Mohammed Khaleel , Jameel M , Ibrahim Zainah , Tan Chee
Published: August 2021

The performance of precast concrete frame structures against seismic loads mainly depends on the beam-to-column connection. A ductile hybrid connection consists of unbonded post-tensioning steel and bonded reinforcement bars, both of which provide overall moment resistance to the frame. Post-tensioning steel acts as a restoring force which brings the structure back to its initial position upon unloading. Mild steel acts as an energy dissipator which yields in tension and compression. To evaluate the performance of precast frame structures, the structural engineer requires extensive knowledge of the complex nonlinear behavior of the connection. Standardization to mass produce is one of the benefits of precast construction, but with standardization in design there is severe risk. All previous earthquakes have clearly shown that continuous repetition of accepted practice without proper engineering review can lead to disaster. It is important to understand how different parameters of the connection influence the behavior and performance of the frame against seismic loads. The present study helps structural engineers and researchers with a detailed review of hybrid post-tensioned connections. This review is focused mainly on precast beam-to-column connections, studies on the development of hybrid connections, performance evaluations of hybrid connections, and the performance evaluation of precast frames with hybrid connections.
Species-Specific Molecular Detection of the Root Knot Nematode Meloidogyne luci
Authors: Maleita Carla , Cardoso Joana M. S. , Rusinque Leidy , Esteves Ivânia , Abrantes Isabel
Published: August 2021

Meloidogyne luci has been identified in various countries around the world parasitizing economically important crops and, due to its potential to cause serious damage to agriculture, was included in the European and Mediterranean Plant Protection Organization Alert List in 2017. This species shares morphological and molecular similarities with M. ethiopica and M. inornata, and a M. ethiopica group was therefore established. Although specific primers for the DNA amplification of species belonging to the M. ethiopica group have been developed previously, the primers were not species-specific, so molecular markers for the specific detection of M. luci are still needed. The objective of this study was to develop a SCAR marker for the detection of M. luci and the discrimination from other Meloidogyne spp. based on the intraspecific variability found in RAPD markers. RAPD screening of M. luci and M. ethiopica genome was used for the identification of a specific amplification product on M. luci, which was cloned, sequenced and converted into a SCAR marker. The specificity of the designed primers (Mlf/r) was tested and produced a fragment (771 bp) for all nine M. luci isolates with no amplification for the other nine Meloidogyne spp., including M. ethiopica and M. inornata. Additionally, the proper amplification of the M. luci SCAR-marker was also successful with DNA from galls of M. luci infected tomato roots. The results obtained in this study reveal that the specific molecular detection of M. luci was achieved and that the developed methodology can be used for routine diagnosis purposes, which are essential to monitoring the distribution and spread of M. luci in order to implement future effective and integrated nematode pest management programs.
A Time-Saving Strategy to Generate Double Maternal Mutants by an Oocyte-Specific Conditional Knockout System in Zebrafish
Authors: Zhang Chong , Li Jiaguang , Tarique Imran , Zhang Yizhuang , Lu Tong , Wang Jiasheng , Chen Aijun , Wen Fenfen , Zhang Zhuoyu , Zhang Yanjun , Shao Ming
Published: August 2021

Maternal products are those mRNAs and proteins deposited during oogenesis, which play critical roles in controlling oocyte formation, fertilization, and early embryonic development. However, loss-of-function studies for these maternal factors are still lacking, mainly because of the prolonged period of transgenerational screening and technical barriers that prevent the generation of maternal (M) and maternal and zygotic (MZ) mutant embryos. By the transgenic expression of multiple sgRNAs targeting a single gene of interest in the background of a transgenic line Tg(zpc:zcas9) with oocyte-specific cas9 expression, we have successfully obtained maternal or maternal–zygotic mutant for single genes in F1 embryos. In this work, we tandemly connected a maternal GFP marker and eight sgRNA expression units to target dvl2 and dvl3a simultaneously and introduced this construct to the genome of Tg(zpc:zcas9) by meganuclease I-Sce I. As expected, we confirmed the existence of Mdvl2;Mdvl3a embryos with strong defective convergence and extension movement during gastrulation among outcrossed GFP positive F1 offspring. The MZdvl2;MZdvl3a embryos were also obtained by crossing the mutant carrying mosaic F0 female with dvl2+/−;dvl3a−/− male fish. This proof-of-principle thus highlights the potential of this conditional knockout strategy to circumvent the current difficulty in the study of genes with multiple functionally redundant paralogs.
GNAi2/gip2-Regulated Transcriptome and Its Therapeutic Significance in Ovarian Cancer
Authors: Ha Ji Hee , Jayaraman Muralidharan , Yan Mingda , Dhanasekaran Padmaja , Isidoro Ciro , Song Yong Sang , Dhanasekaran Danny N.
Published: August 2021

Increased expression of GNAi2, which encodes the α-subunit of G-protein i2, has been correlated with the late-stage progression of ovarian cancer. GNAi2, also referred to as the proto-oncogene gip2, transduces signals from lysophosphatidic acid (LPA)-activated LPA-receptors to oncogenic cellular responses in ovarian cancer cells. To identify the oncogenic program activated by gip2, we carried out micro-array-based transcriptomic and bioinformatic analyses using the ovarian cancer cell-line SKOV3, in which the expression of GNAi2/gip2 was silenced by specific shRNA. A cut-off value of 5-fold change in gene expression (p < 0.05) indicated that a total of 264 genes were dependent upon gip2-expression with 136 genes coding for functional proteins. Functional annotation of the transcriptome indicated the hitherto unknown role of gip2 in stimulating the expression of oncogenic/growth-promoting genes such as KDR/VEGFR2, CCL20, and VIP. The array results were further validated in a panel of High-Grade Serous Ovarian Carcinoma (HGSOC) cell lines that included Kuramochi, OVCAR3, and OVCAR8 cells. Gene set enrichment analyses using DAVID, STRING, and Cytoscape applications indicated the potential role of the gip2-stimulated transcriptomic network involved in the upregulation of cell proliferation, adhesion, migration, cellular metabolism, and therapy resistance. The results unravel a multi-modular network in which the hub and bottleneck nodes are defined by ACKR3/CXCR7, IL6, VEGFA, CYCS, COX5B, UQCRC1, UQCRFS1, and FYN. The identification of these genes as the critical nodes in GNAi2/gip2 orchestrated onco-transcriptome establishes their role in ovarian cancer pathophysiology. In addition, these results also point to these nodes as potential targets for novel therapeutic strategies.
Serotonin Signalling in Flatworms: An Immunocytochemical Localisation of 5-HT7 Type of Serotonin Receptors in Opisthorchis felineus and Hymenolepis diminuta
Authors: Kreshchenko Natalia , Terenina Nadezhda , Ermakov Artem
Published: August 2021

The study is dedicated to the investigation of serotonin (5-hydroxytryptamine, 5-HT) and 5-HT7 type serotonin receptor of localisation in larvae of two parasitic flatworms Opisthorchis felineus (Rivolta, 1884) Blanchard, 1895 and Hymenolepis diminuta Rudolphi, 1819, performed using the immunocytochemical method and confocal laser scanning microscopy (CLSM). Using whole mount preparations and specific antibodies, a microscopic analysis of the spatial distribution of 5-HT7-immunoreactivity(-IR) was revealed in worm tissue. In metacercariae of O. felineus 5-HT7-IR was observed in the main nerve cords and in the head commissure connecting the head ganglia. The presence of 5-HT7-IR was also found in several structures located on the oral sucker. 5-HT7-IR was evident in the round glandular cells scattered throughout the larva body. In cysticercoids of H. diminuta immunostaining to 5-HT7 was found in flame cells of the excretory system. Weak staining to 5-HT7 was observed along the longitudinal and transverse muscle fibres comprising the body wall and musculature of suckers, in thin longitudinal nerve cords and a connective commissure of the central nervous system. Available publications on serotonin action in flatworms and serotonin receptors identification were reviewed. Own results and the published data indicate that the muscular structures of flatworms are deeply supplied by 5-HT7-IR elements. It suggests that the 5-HT7 type receptor can mediate the serotonin action in the investigated species and is an important component of the flatworm motor control system. The study of the neurochemical basis of parasitic flatworms can play an important role in the solution of fundamental problems in early development of the nervous system and the evolution of neuronal signalling components.
Concentration Sensitivity of Nucleic Acid and Protein Molecule Detection Using Nanowire Biosensors
Authors: Ivanov Yuri D. , Tatur Vadim Yu. , Glukhov Alexander V. , Ziborov Vadim S.
Published: August 2021

The concentration detection limit (DL) of biomacromolecules attainable using a nanowire detector has become a topical issue. A DL of 10−15 M is required to reveal oncological and infectious diseases at an early stage. This study discusses the DL experimentally attainable in the subfemtomolar concentration range, and possible mechanisms explaining such a low-concentration DL through the cooperative effect of biomacromolecular complexes formed on the surface of the nanowire (NW) chip near the nanowire.
Influence of the Type of Aggregate from Industrial Waste on Corrosion Resistance of Modified Fine-Grained Concrete
Authors: Zajceva Ljajsjan , Lucyk Ekaterina , Latypova Tat’jana , Latypov Valerij , Fedorov Pavel , Salamanova Madina
Published: August 2021

The development and implementation of “green” technologies in the construction sector, which ensure natural resource conservation, reduce harmful emissions and provide utilization of industrial waste, are key issues in material engineering of the XXI century. Extensive research has been devoted to solving these issues, including research in the field of concrete science. Still, the issue of developing concrete compositions with increased corrosion resistance remains much less studied. At the same time, reactive aggregates from industrial waste can have positive effect on durability of concrete, and the best result can be achieved by means of modification of a concrete mixture with highly effective additives. The article presents the research data in two lines—the study of applicability of reactive aggregates from waste products of nonmetallic and ceramic industries, mineral wool production and concrete scrap for production of corrosion-resistant concretes, as well as the assessment of possibility of Portland cement quantity reduction in a concrete mixture on local raw materials due to the introduction of additives based on polycarboxylates. The article presents the research evidence of the effect of dust and clay particles content on the quality of concrete with a polycarboxylate additive. The article describes the studies of corrosion resistance of concrete samples based on production wastes in sulfate environments and under the influence of carbon dioxide. The developed concrete compositions with waste use can be recommended for widespread application, rational use of resources, and production of durable high-quality concretes. The application of additives based on polycarboxylates makes it possible to produce concretes with the reduction of cement consumption in the mixture by 10–20% and decrease in the mode of thermo-wet treatment by two times.
Degradation Efficiency and Kinetics Analysis of an Advanced Oxidation Process Utilizing Ozone, Hydrogen Peroxide and Persulfate to Degrade the Dye Rhodamine B
Authors: Zawadzki Piotr , Deska Małgorzata
Published: August 2021

In this study, the effectiveness of a rhodamine B (RhB) dye degradation process at a concentration of 20 mg/L in different advanced oxidation processes—H2O2/UV, O3/UV and PDS/UV—has been studied. The use of UV in a photo-assisted ozonation process (O3/UV) proved to be the most effective method of RhB decolorization (90% after 30 min at dye concentration of 100 mg/L). The addition of sulfate radical precursors (sodium persulfate, PDS) to the reaction environment did not give satisfactory effects (17% after 30 min), compared to the PDS/UV system (70% after 30 min). No rhodamine B decolorization was observed using hydrogen peroxide as a sole reagent, whereas an effect on the degree of RhB degradation was observed when UV rays strike the sample with H2O2 (33% after 30 min). The rhodamine B degradation process followed the pseudo-first-order kinetics model. The combined PDS/O3/UV process has shown 60% color removal after 30 min of reaction time at an initial dye concentration of 100 mg/L. A similar effectiveness was obtained by only applying ozone or UV-activated persulfate, but at a concentration 2–5 times lower (20 mg/L). The results indicated that the combined PDS/O3/UV process is a promising method for high RhB concentrations (50–100 mg/L) comparing to other alternative advanced oxidation processes.
Increased Hypothalamic Anti-Inflammatory Mediators in Non-Diabetic Insulin Receptor Substrate 2-Deficient Mice
Authors: Vinaixa María , Canelles Sandra , González-Murillo África , Ferreira Vítor , Grajales Diana , Guerra-Cantera Santiago , Campillo-Calatayud Ana , Ramírez-Orellana Manuel , Yanes Óscar , Frago Laura M. , Valverde Ángela M. , Barrios Vicente
Published: August 2021

Insulin receptor substrate (IRS) 2 is a key mediator of insulin signaling and IRS-2 knockout (IRS2−/−) mice are a preclinical model to study the development of diabetes, as they develop peripheral insulin resistance and beta-cell failure. The differential inflammatory profile and insulin signaling in the hypothalamus of non-diabetic (ND) and diabetic (D) IRS2−/− mice might be implicated in the onset of diabetes. Because the lipid profile is related to changes in inflammation and insulin sensitivity, we analyzed whether ND IRS2−/− mice presented a different hypothalamic fatty acid metabolism and lipid pattern than D IRS2−/− mice and the relationship with inflammation and markers of insulin sensitivity. ND IRS2−/− mice showed elevated hypothalamic anti-inflammatory cytokines, while D IRS2−/− mice displayed a proinflammatory profile. The increased activity of enzymes related to the pentose-phosphate route and lipid anabolism and elevated polyunsaturated fatty acid levels were found in the hypothalamus of ND IRS2−/− mice. Conversely, D IRS2−/− mice have no changes in fatty acid composition, but hypothalamic energy balance and markers related to anti-inflammatory and insulin-sensitizing properties were reduced. The data suggest that the concurrence of an anti-inflammatory profile, increased insulin sensitivity and polyunsaturated fatty acids content in the hypothalamus may slow down or delay the onset of diabetes.
Cell Therapy for Anal Sphincter Incontinence: Where Do We Stand?
Authors: Balaphas Alexandre , Meyer Jeremy , Meier Raphael , Liot Emilie , Buchs Nicolas , Roche Bruno , Toso Christian , Bühler Leo , Gonelle-Gispert Carmen , Ris Frédéric
Published: August 2021

Anal sphincter incontinence is a chronic disease, which dramatically impairs quality of life and induces high costs for the society. Surgery, considered as the best curative option, shows a disappointing success rate. Stem/progenitor cell therapy is pledging, for anal sphincter incontinence, a substitute to surgery with higher efficacy. However, the published literature is disparate. Our aim was to perform a review on the development of cell therapy for anal sphincter incontinence with critical analyses of its pitfalls. Animal models for anal sphincter incontinence were varied and tried to reproduce distinct clinical situations (acute injury or healed injury with or without surgical reconstruction) but were limited by anatomical considerations. Cell preparations used for treatment, originated, in order of frequency, from skeletal muscle, bone marrow or fat tissue. The characterization of these preparations was often incomplete and stemness not always addressed. Despite a lack of understanding of sphincter healing processes and the exact mechanism of action of cell preparations, this treatment was evaluated in 83 incontinent patients, reporting encouraging results. However, further development is necessary to establish the correct indications, to determine the most-suited cell type, to standardize the cell preparation method and to validate the route and number of cell delivery.
GSK3 as a Regulator of Cytoskeleton Architecture: Consequences for Health and Disease
Authors: Hajka Daria , Budziak Bartosz , Pietras Łukasz , Duda Przemysław , McCubrey James A. , Gizak Agnieszka
Published: August 2021

Glycogen synthase kinase 3 (GSK3) was initially isolated as a critical protein in energy metabolism. However, subsequent studies indicate that GSK-3 is a multi-tasking kinase that links numerous signaling pathways in a cell and plays a vital role in the regulation of many aspects of cellular physiology. As a regulator of actin and tubulin cytoskeleton, GSK3 influences processes of cell polarization, interaction with the extracellular matrix, and directional migration of cells and their organelles during the growth and development of an animal organism. In this review, the roles of GSK3–cytoskeleton interactions in brain development and pathology, migration of healthy and cancer cells, and in cellular trafficking of mitochondria will be discussed.
Gas Chromatography Multiresidue Method for Enantiomeric Fraction Determination of Psychoactive Substances in Effluents and River Surface Waters
Authors: Langa Ivan , Tiritan Maria Elizabeth , Silva Diana , Ribeiro Cláudia
Published: August 2021

Determination of psychoactive substances (PAS) and/or their metabolites in surface waters is crucial for environmental risk assessment, and disclosure of their enantiomeric fractions (EF) allows discrimination between consumption, direct disposal, and synthesis pathways. The aim of this study was to develop and validate an indirect method by gas chromatography coupled to mass spectrometry (GC–MS) based on derivatization using (R)-(−)-α-methoxy-α-(trifluoromethyl) phenylacetyl chloride as chiral derivatization reagent, for enantiomeric quantification of amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxymethamphetamine (MDMA), norketamine, buphedrone (BPD), butylone, 3,4-dimethylmethcathinone (3,4-DMMC), 3-methylmethcathinone, and quantification of 1-benzylpiperazine and 1-(4-metoxyphenyl)-piperazine. The method allowed to evaluate the occurrence, spatial distribution, and the EF of the target chiral PAS in Portuguese surface waters and in effluents from 2 wastewater treatment plants (WWTP). For that, water samples were pre-concentrated by solid phase extraction using OASIS® MCX cartridges, derivatized and further analyzed by GC–MS. Both enantiomers of AMP, (R)-MDMA, (S)-MAMP, and the first eluted enantiomer of BPD (configuration not assigned) were found in surface waters, while effluent samples showed both enantiomers of MDMA, (S)-MAMP, (R)-AMP, and the first eluted enantiomer of BPD and 3,4-DMMC. According to our knowledge, this is the first multiresidue analytical method by CG–MS enrolling cathinones, amphetamines, and piperazines. The presence of illicit synthetic cathinones in Douro River estuary is here reported for the first time, along with other amphetamine derivatives. The potential of the method to monitor consumption of the target PAS was demonstrated.
Anti-Corrosion Behavior of Olmesartan for Soft-Cast Steel in 1 mol dm−3 HCl
Authors: Praveen B. M. , Alhadhrami A. , Prasanna B. M. , Hebbar Narayana , Prabhu Radhakrishna
Published: August 2021

This study discusses the effects of temperature on corrosion inhibition for soft-cast steel by the pharmaceutically active drug olmesartan in 1 mol dm−3 HCl. The sufficient number of electron-rich elements and non-bonding π electrons in its structure favored a good capability for coating onto the electron-deficient steel surfaces. Theoretical and electrochemical measurements were carried out at the temperature region of 303 K to 333 K. Therefore, the experiment suggests that the inhibition efficiency of olmesartan increases with its increasing concentrations due to the adsorption. Additionally, even at a higher temperature of 333 K, the inhibitor molecules attain their stability towards corrosion resistance of steel surfaces. The adsorption of inhibitors on steel surfaces is spontaneously found to include the mixture of physisorption and chemisorption, and it obeys Temkin’s adsorption isotherm model. Theoretical and computational considerations were made using quantum chemical parameters and molecular dynamics simulations, which confirmed that the olmesartan has a suitable corrosion inhibitive capability intended for soft-cast steel in 1 mol dm−3 HCl. Additionally, scanning electron microscopic measurement was used to obtain a visual idea of the inhibitive action of the inhibitor attained by forming an adsorbed protective layer onto the steel surfaces. The minute concentration of olmesartan of about 10–50 ppm shows high inhibition efficiency of ~80%, even at elevated temperatures.
Sapphire-Derived Fiber Bragg Gratings for High Temperature Sensing
Authors: Guo Qi , Jia Zhixu , Pan Xuepeng , Liu Shanren , Tian Zhennan , Zheng Zhongming , Chen Chao , Qin Guanshi , Yu Yongsen
Published: August 2021

In this paper, a sapphire-derived fiber (SDF) with a core diameter of 10 μm and a cladding diameter of 125 μm is fabricated by the melt-in-tube method, and fiber Bragg gratings (FBGs) with reflectivity over 80% are prepared by the femtosecond laser point-by-point direct writing method. By analyzing the refractive index distribution and reflection spectral characteristics of the SDF, it can be seen that the SDF is a graded refractive index few-mode fiber. In order to study the element composition of the SDF core, the end-face element distribution of the SDF is analyzed, which indicates that element diffusion occurred between the core and the cladding materials. The temperature and stress of the SDF gratings are measured and the highest temperature is tested to 1000 °C. The temperature and strain sensitivities are 15.64 pm/°C and 1.33 pm/με, respectively, which are higher than the temperature sensitivity of the quartz single-mode fiber. As a kind of special fiber, the SDF expands the application range of sapphire fiber, and has important applications in the fields of high-temperature sensing and high-power lasers.
Paraffin Wax [As a Phase Changing Material (PCM)] Based Composites Containing Multi-Walled Carbon Nanotubes for Thermal Energy Storage (TES) Development
Authors: Almousa Norah Hamad , Alotaibi Maha R. , Alsohybani Mohammad , Radziszewski Dominik , AlNoman Saeed M. , Alotaibi Bandar M. , Khayyat Maha M.
Published: August 2021

Thermal energy storage (TES) technologies are considered as enabling and supporting technologies for more sustainable and reliable energy generation methods such as solar thermal and concentrated solar power. A thorough investigation of the TES system using paraffin wax (PW) as a phase changing material (PCM) should be considered. One of the possible approaches for improving the overall performance of the TES system is to enhance the thermal properties of the energy storage materials of PW. The current study investigated some of the properties of PW doped with nano-additives, namely, multi-walled carbon nanotubes (MWCNs), forming a nanocomposite PCM. The paraffin/MWCNT composite PCMs were tailor-made for enhanced and efficient TES applications. The thermal storage efficiency of the current TES bed system was approximately 71%, which is significant. Scanning electron spectroscopy (SEM) with energy dispersive X-ray (EDX) characterization showed the physical incorporation of MWCNTs with PW, which was achieved by strong interfaces without microcracks. In addition, the FTIR (Fourier transform infrared) and TGA (thermogravimetric analysis) experimental results of this composite PCM showed good chemical compatibility and thermal stability. This was elucidated based on the observed similar thermal mass loss profiles as well as the identical chemical bond peaks for all of the tested samples (PW, CNT, and PW/CNT composites).
Precise Epigenetic Analysis Using Targeted Bisulfite Genomic Sequencing Distinguishes FSHD1, FSHD2, and Healthy Subjects
Authors: Gould Taylor , Jones Takako I. , Jones Peter L.
Published: August 2021

The true prevalence of facioscapulohumeral muscular dystrophy (FSHD) is unknown due to difficulties with accurate clinical evaluation and the complexities of current genetic diagnostics. Interestingly, all forms of FSHD are linked to epigenetic changes in the chromosome 4q35 D4Z4 macrosatellite, suggesting that epigenetic analysis could provide an avenue for sequence-based FSHD diagnostics. However, studies assessing DNA methylation at the FSHD locus have produced conflicting results; thus, the utility of this technique as an FSHD diagnostic remains controversial. Here, we critically compared two protocols for epigenetic analysis of the FSHD region using bisulfite genomic sequencing: Jones et al., that contends to be individually diagnostic for FSHD1 and FSHD2, and Gaillard et al., that can identify some changes in DNA methylation levels between groups of clinically affected FSHD and healthy subjects, but is not individually diagnostic for any form of FSHD. We performed both sets of assays on the same genetically confirmed samples and showed that this discrepancy was due strictly to differences in amplicon specificity. We propose that the epigenetic status of the FSHD-associated D4Z4 arrays, when accurately assessed, is a diagnostic for genetic FSHD and can readily distinguish between healthy, FSHD1 and FSHD2. Thus, epigenetic diagnosis of FSHD, which can be performed on saliva DNA, will greatly increase accessibility to FSHD diagnostics for populations around the world.
Ultrasound Measurement of Tumor-Free Distance from the Serosal Surface as the Alternative to Measuring the Depth of Myometrial Invasion in Predicting Lymph Node Metastases in Endometrial Cancer
Authors: Liro Marcin , Śniadecki Marcin , Wycinka Ewa , Wojtylak Szymon , Brzeziński Michał , Stańczak Agata , Wydra Dariusz
Published: August 2021

Background: Ultrasonography’s usefulness in endometrial cancer (EC) diagnosis consists in its roles in staging and prediction of metastasis. Ultrasound-measured tumor-free distance from the tumor to the uterine serosa (uTFD) is a promising marker for these diagnostic and prognostic variables. The aim of the study was to determine the usefulness of this biomarker in locoregional staging, and thus in the prediction of lymph node metastasis (LNM). Methods: We conducted a single-institutional, prospective study on 116 consecutive patients with EC who underwent 2D transvaginal ultrasound examination. The uTFD marker was compared with the depth of ultrasound-measured myometrial invasion (uMI). Univariable and multivariable logit models were evaluated to assess the predictive power of the uTFD and uMI in regard to LNM. The reference standard was a final histopathology result. Survival was assessed by the Kaplan–Meier method. Results: LNM was found in 17% of the patients (20/116). In the univariable analysis, uMI and uTFD were significant predictors of LNM. The accuracy was 70.7%, and the NPV was 92.68% (OR 4.746, 95% CI 1.710–13.174) for uMI (p = 0.002), and they were 63.8% and 89.02% (OR 0.842, 95% CI 0.736–0.963), respectively, for uTFD (p = 0.01). The cutoff value for uTFD in the prediction of LNM was 5.2 mm. The association between absence of LNM and biomarker values of uMI < 1/2 and uTFD ≥ 5.2 mm was greater than that between the presence of metastases and uMI > 1/2 and uTFD values <5.2 mm. In the multivariable analysis, the accuracy of the uMI–uTFD model was 74%, and its NPV was 90.24% (p = non-significant). Neither uMI nor uTFD were surrogates for overall and recurrence-free survivals in endometrial cancer. Conclusions: Both uMI and uTFD, either alone or in combination, were valuable tools for gaining additional preoperative information on expected lymph node status. Negative lymph nodes status was better described by ultrasound biomarkers than a positive status. It was easier to use the uTFD rather than the uMI measurement as a biomarker of EC invasion, and the former still maintained a similar predictive value for lymph node metastases to the latter at diagnosis.
Automated Mesiodens Classification System Using Deep Learning on Panoramic Radiographs of Children
Authors: Ahn Younghyun , Hwang Jae Joon , Jung Yun-Hoa , Jeong Taesung , Shin Jonghyun
Published: August 2021

In this study, we aimed to develop and evaluate the performance of deep-learning models that automatically classify mesiodens in primary or mixed dentition panoramic radiographs. Panoramic radiographs of 550 patients with mesiodens and 550 patients without mesiodens were used. Primary or mixed dentition patients were included. SqueezeNet, ResNet-18, ResNet-101, and Inception-ResNet-V2 were each used to create deep-learning models. The accuracy, precision, recall, and F1 score of ResNet-101 and Inception-ResNet-V2 were higher than 90%. SqueezeNet exhibited relatively inferior results. In addition, we attempted to visualize the models using a class activation map. In images with mesiodens, the deep-learning models focused on the actual locations of the mesiodens in many cases. Deep-learning technologies may help clinicians with insufficient clinical experience in more accurate and faster diagnosis.
Association between Change in Regional Phase Angle and Jump Performance: A Pilot Study in Serie A Soccer Players
Authors: Bongiovanni Tindaro , Trecroci Athos , Rossi Alessio , Iaia Fedon Marcello , Pasta Giulio , Campa Francesco
Published: August 2021

Purpose: This observational longitudinal investigation aimed to investigate whether change in bioelectrical regional phase angle (PhA) is a predictor of change in vertical jump performance in elite soccer players. Methods: Fifteen soccer players (age: 28.7 ± 5.0 years, body weight: 82.4 ± 6.8 kg, height: 186.0 ± 0.1 cm, body mass index: 23.8 ± 1.2 kg/m2) competing in the first Italian division (Serie A) were included in this study and tested before the pre-season period and after the first half of the championship. Whole body and lower hemisoma PhA were obtained with a phase-sensitive 50 kHz bioelectrical impedance analyzer and legs lean soft tissue was estimated using specific bioimpedance-based equation developed for athletes. Vertical jump performance was assessed using the countermovement jump (CMJ). Results: The major findings of the study are that changes in lower hemisoma PhA are more strongly related with changes in jump performance (r2 = 0.617, p = 0.001) than changes in whole-body PhA (r2 = 0.270, p = 0.047), even after adjusting for legs lean soft tissue and for body mass index (β = 5.17, p = 0.004). Conclusions: These data suggest that changes in lower hemisoma PhA might be used as a tool for evaluating performance related parameters in sports where specific body segments are involved, in preference to the whole-body measured value.
A Configurable RO-PUF for Securing Embedded Systems Implemented on Programmable Devices
Authors: Martínez-Rodríguez Macarena C. , Camacho-Ruiz Eros , Brox Piedad , Sánchez-Solano Santiago
Published: August 2021

Improving the security of electronic devices that support innovative critical services (digital administrative services, e-health, e-shopping, and on-line banking) is essential to lay the foundations of a secure digital society. Security schemes based on Physical Unclonable Functions (PUFs) take advantage of intrinsic characteristics of the hardware for the online generation of unique digital identifiers and cryptographic keys that allow to ensure the protection of the devices against counterfeiting and to preserve data privacy. This paper tackles the design of a configurable Ring Oscillator (RO) PUF that encompasses several strategies to provide an efficient solution in terms of area, timing response, and performance. RO-PUF implementation on programmable logic devices is conceived to minimize the use of available resources, while operating speed can be optimized by properly selecting the size of the elements used to obtain the PUF response. The work also describes the interface added to the PUF to facilitate its incorporation as hardware Intellectual Property (IP)-modules into embedded systems. The performance of the RO-PUF is proven with an extensive battery of tests, which are executed to analyze the influence of different test strategies on the PUF quality indexes. The configurability of the proposed RO-PUF allows establishing the most suitable “cost/performance/security-level” trade-off for a certain application.
Real-Time Semantic Segmentation of 3D Point Cloud for Autonomous Driving
Authors: Kang Dongwan , Wong Anthony , Lee Banghyon , Kim Jungha
Published: August 2021

Autonomous vehicles perceive objects through various sensors. Cameras, radar, and LiDAR are generally used as vehicle sensors, each of which has its own characteristics. As examples, cameras are used for a high-level understanding of a scene, radar is applied to weather-resistant distance perception, and LiDAR is used for accurate distance recognition. The ability of a camera to understand a scene has overwhelmingly increased with the recent development of deep learning. In addition, technologies that emulate other sensors using a single sensor are being developed. Therefore, in this study, a LiDAR data-based scene understanding method was developed through deep learning. The approaches to accessing LiDAR data through deep learning are mainly divided into point, projection, and voxel methods. The purpose of this study is to apply a projection method to secure a real-time performance. The convolutional neural network method used by a conventional camera can be easily applied to the projection method. In addition, an adaptive break point detector method used for conventional 2D LiDAR information is utilized to solve the misclassification caused by the conversion from 2D into 3D. The results of this study are evaluated through a comparison with other technologies.
Classification of Targets Using Statistical Features from Range FFT of mmWave FMCW Radars
Authors: Bhatia Jyoti , Dayal Aveen , Jha Ajit , Vishvakarma Santosh Kumar , Joshi Soumya , Srinivas M. B. , Yalavarthy Phaneendra K. , Kumar Abhinav , Lalitha V. , Koorapati Sagar , Cenkeramaddi Linga Reddy
Published: August 2021

Radars with mmWave frequency modulated continuous wave (FMCW) technology accurately estimate the range and velocity of targets in their field of view (FoV). The targeted angle of arrival (AoA) estimation can be improved by increasing receiving antennas or by using multiple-input multiple-output (MIMO). However, obtaining target features such as target type remains challenging. In this paper, we present a novel target classification method based on machine learning and features extracted from a range fast Fourier transform (FFT) profile by using mmWave FMCW radars operating in the frequency range of 77–81 GHz. The measurements are carried out in a variety of realistic situations, including pedestrian, automotive, and unmanned aerial vehicle (UAV) (also known as drone). Peak, width, area, variance, and range are collected from range FFT profile peaks and fed into a machine learning model. In order to evaluate the performance, various light weight classification machine learning models such as logistic regression, Naive Bayes, support vector machine (SVM), and lightweight gradient boosting machine (GBM) are used. We demonstrate our findings by using outdoor measurements and achieve a classification accuracy of 95.6% by using LightGBM. The proposed method will be extremely useful in a wide range of applications, including cost-effective and dependable ground station traffic management and control systems for autonomous operations, and advanced driver-assistance systems (ADAS). The presented classification technique extends the potential of mmWave FMCW radar beyond the detection of range, velocity, and AoA to classification. mmWave FMCW radars will be more robust in computer vision, visual perception, and fully autonomous ground control and traffic management cyber-physical systems as a result of the added new feature.
High-Linearity Direct Conversion Receiver with the Transconductance Equalization Technique and DCOC Method
Authors: Han Yiming , Wang Fengjie , Liu Jiarui , Wang Zhiyu , Yu Faxin
Published: August 2021

To improve the linearity of direct conversion receivers (DCRs), two high-linearity methods for high second-order intercept points (IP2s) and high third-order intercept points (IP3s) are proposed. To improve IP3s, a transconductance equalization technique for a complementary input operational amplifier (OPAMP) is proposed in an active-RC low-pass filter (LPF), while a digital-analog hybrid DC offset calibration (DCOC) method is proposed to improve IP2s. For one thing, the proposed transconductance equalization technique employs a pair of resistors to guarantee high voltage gain for an OPAMP with two-stage Miller topology under a high-input voltage swing to improve linearity with little deterioration of the noise performance. For another, during the DCOC method, the low-noise amplifier is turned off and replaced by an equivalent resistance of the output impedance of the low-noise amplifier to ensure the accuracy and effectiveness of the DCOC method. Fabricated in 40-nm CMOS technology, the receiver with proposed methods can realize a noise figure of 2.6–3.5 dB in the full frequency band, with an OIP3 of 28 dBm, an IM2 more than 70 dBc, and a remaining DC of −53.2 dBm under the total voltage gain of 60 dB.
Computational Intelligence Technologies for Occupancy Estimation and Comfort Control in Buildings
Authors: Korkidis Panagiotis , Dounis Anastasios , Kofinas Panagiotis
Published: August 2021

This paper focuses on the development of a multi agent control system (MACS), combined with a stochastic based approach for occupancy estimation. The control framework aims to maintain the comfort levels of a building in high levels and reduce the overall energy consumption. Three independent agents, each dedicated to the thermal comfort, the visual comfort, and the indoor air quality, are deployed. A stochastic model describing the CO2 concentration has been studied, focused on the occupancy estimation problem. A probabilistic approach, as well as an evolutionary algorithm, are used to provide insights on the stochastic model. Moreover, in order to induce uncertainty, parameters are treated in a fuzzy modelling framework and the results on the occupancy estimation are investigated. In the control framework, to cope with the continuous state-action space, the three agents utilise Fuzzy Q-learning. Simulation results highlight the precision of parameter and occupancy estimation, as well as the high capabilities of the control framework, when taking into account the occupancy state, as energy consumption is reduced by 55.9%, while the overall comfort index is kept in high levels, with values close to one.
Crowdsourcing Framework for QoE-Aware SD-WAN
Authors: Ellawindy Ibtihal , Shah Heydari Shahram
Published: August 2021

Quality of experience (QoE) is an important measure of users’ satisfaction regarding their network-based services, and it is widely employed today to provide a real assessment of the service quality as perceived by the end users. QoE measures can be used to improve application performance, as well as to optimize network resources and reallocate them as needed when the service quality degrades. While quantitative QoE assessments based on network parameters may provide insights into users’ experience, subjective assessments through direct feedback from the users have also gathered interest recently due to their accuracy and interactive nature. In this paper, we propose a framework that can be used to collect real-time QoE feedback through crowdsourcing and forward it to network controllers to enhance streaming routes. We analyze how QoE can be affected by different network conditions, and how different streaming protocols compare against each other when the network parameters change dynamically. We also compare the real-time user feedback to predefined network changes to measure if participants will be able to identify all degradation events, as well as to examine which combination of degradation events are noticeable to the participants. Our aim is to demonstrate that real-time QoE feedback can enhance cloud-based services and can adjust service quality on the basis of real-time, active participants’ interactions.
From Mangrove to Fork: Metal Presence in the Guayas Estuary (Ecuador) and Commercial Mangrove Crabs
Authors: De Cock Andrée , De Troyer Niels , Eurie Marie Anne Forio , Garcia Arevalo Isabel , Van Echelpoel Wout , Jacxsens Liesbeth , Luca Stijn , Du Laing Gijs , Tack Filip , Dominguez Granda Luis , Goethals Peter L. M.
Published: August 2021

Mangrove wetlands provide essential ecosystem services such as coastal protection and fisheries. Metal pollution due to industrial and agricultural activities represents an issue of growing concern for the Guayas River Basin and related mangroves in Ecuador. Fisheries and the related human consumption of mangrove crabs are in need of scientific support. In order to protect human health and aid river management, we analyzed several elements in the Guayas Estuary. Zn, Cu, Ni, Cr, As, Pb, Cd, and Hg accumulation were assessed in different compartments of the commercial red mangrove crab Ucides occidentalis (hepatopancreas, carapax, and white meat) and the environment (sediment, leaves, and water), sampled at fifteen sites over five stations. Consistent spatial distribution of metals in the Guayas estuary was found. Nickel levels in the sediment warn for ecological caution. The presence of As in the crabs generated potential concerns on the consumers’ health, and a maximum intake of eight crabs per month for adults is advised. The research outcomes are of global importance for at least nine Sustainable Development Goals (SDGs). The results presented can support raising awareness about the ongoing contamination of food and their related ecosystems and the corresponding consequences for environmental and human health worldwide.