bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeting HSF1 as a Therapeutic Strategy for Multiple Mechanisms of EGFR Inhibitor Resistance in EGFR Mutant Non-Small-Cell Lung Cancer
Authors: Lee Sangah , Jung Jiyae , Lee Yu-Jin , Kim Seon-Kyu , Kim Jung-Ae , Kim Bo-Kyung , Park Kyung Chan , Kwon Byoung-Mog , Han Dong Cho
Published: June 2021

Although EGFR-TKI treatment of NSCLC (non-small-cell lung cancer) patients often achieves profound initial responses, the efficacy is transient due to acquired resistance. Multiple receptor tyrosine kinase (RTK) pathways contribute to the resistance of NSCLC to first- and third-generation EGFR-TKIs, such as erlotinib and osimertinib. To identify potential targets for overcoming EGFR-TKI resistance, we performed a gene expression signature-based strategy using connectivity map (CMap) analysis. We generated erlotinib-resistant HCC827-ErlR cells, which showed resistance to erlotinib, gefitinib, osimertinib, and doxorubicin. A list of differentially expressed genes (DEGs) in HCC827-ErlR cells was generated and queried using CMap analysis. Analysis of the top 4 compounds from the CMap list suggested HSF1 as a potential target to overcome EGFR-TKI resistance. HSF1 inhibition by using HSF1 shRNAs or KRIBB11 decreased the expression of HSF1 downstream proteins, such as HSP70 and HSP27, and also decreased the expression of HSP90/HSP70/BAG3 client proteins, such as BCL2, MCL1, EGFR, MET, and AXL, causing apoptosis of EGFR-TKI-resistant cancer cells. Finally, we demonstrated the efficacy of the HSF1 inhibitor on PC9-ErlR cells expressing mutant EGFR (T790M) in vivo. Collectively, these findings support a targetable HSF1-(HSP90/HSP70/BAG3)-(BCL2/MCL1/EGFR/MET/AXL) pathway to overcome multiple mechanisms of EGFR-TKI resistance.
PDLIM2 Suppression Inhibit Proliferation and Metastasis in Kidney Cancer
Authors: Yuk Hyeong-Dong , Lee Kyoung-Hwa , Lee Hye-Sun , Jeong Seung-Hwan , Kho Yongseok , Jeong Chang-Wook , Kim Hyeon-Hoe , Ku Ja-Hyeon , Kwak Cheol
Published: June 2021

We evaluated the expression of PDLIM2 in human kidney cancer cell lines from primary or metastatic origins and found that PDLIM2 expression was highly elevated in metastatic kidney cancers. We evaluated the effect of PDLIM2 inhibition by RNA interference method. PDLIM2 knockdown showed the decreased proliferation and metastatic character in human metastatic kidney cancer cells. By repeated round of orthotopic injection of RenCa mouse kidney cancer cell line, we obtained metastatic prone mouse kidney cancer cell lines. PDLIM2 expression was highly expressed in these metastatic prone cells comparing parental cells. In addition, we evaluated the in vivo efficacy of PDLIM2 knockout on the tumor formation and metastasis of kidney cancer cells using a PDLIM2 knockout mice. The experimental metastasis model with tail vein injection and orthotopic metastasis model injected into kidney all showed reduced lung metastasis cancer formation in PDLIM2 knockout mice comparing control Balb/c mice. Overall, our findings indicate that PDLIM2 is required for cancer formation and metastasis in metastatic kidney cancer, indicating that PDLIM2 may be a new therapeutic target for metastatic kidney cancer.
The Role of MacroH2A Histone Variants in Cancer
Authors: Hsu Chen-Jen , Meers Oliver , Buschbeck Marcus , Heidel Florian H.
Published: June 2021

The epigenome regulates gene expression and provides a molecular memory of cellular events. A growing body of evidence has highlighted the importance of epigenetic regulation in physiological tissue homeostasis and malignant transformation. Among epigenetic mechanisms, the replacement of replication-coupled histones with histone variants is the least understood. Due to differences in protein sequence and genomic distribution, histone variants contribute to the plasticity of the epigenome. Here, we focus on the family of macroH2A histone variants that are particular in having a tripartite structure consisting of a histone fold, an intrinsically disordered linker and a globular macrodomain. We discuss how these domains mediate different molecular functions related to chromatin architecture, transcription and DNA repair. Dysregulated expression of macroH2A histone variants has been observed in different subtypes of cancer and has variable prognostic impact, depending on cellular context and molecular background. We aim to provide a concise review regarding the context- and isoform-dependent contributions of macroH2A histone variants to cancer development and progression.
Preparation of Pd/SiO2 Catalysts by a Simple Dry Ball-Milling Method for Lean Methane Oxidation and Probe of the State of Active Pd Species
Authors: Yang Li , Fan Chao , Luo Li , Chen Yanyan , Wu Zhiwei , Qin Zhangfeng , Dong Mei , Fan Weibin , Wang Jianguo
Published: June 2021

A series of Pd/SiO2 catalysts were prepared with different Pd precursors by a dry ball-milling method and used in the catalytic oxidation of lean methane at low temperature. The effect of Pd precursors on the catalytic performance was investigated and the state of the most active Pd species was probed. The results indicate that dry ball-milling is a simple but rather effective method to prepare the Pd/SiO2 catalysts for lean methane oxidation, and palladium acetylacetonate is an ideal precursor to obtain a highly active Pd/SiO2-Acac catalyst with well- and stably dispersed Pd species, owing to the tight contact between acetylacetonate and Si–OH on the SiO2 support. Besides the size and dispersion of Pd particles, the oxidation state of Pd species also plays a crucial role in determining the catalytic activity of Pd/SiO2 in lean methane oxidation at low temperature. A non-monotonic dependence of the catalytic activity on the Pd oxidation state is observed. The activity of various Pd species follows the order of PdOx >> Pd > PdO; the PdOx/SiO2-Acac catalysts (in particular for PdO0.82/SiO2-Acac when x = 0.82) exhibit much higher activity in lean methane oxidation at low temperature than Pd/SiO2-Acac and PdO/SiO2-Acac. The catalytic activity of PdOx/SiO2 may degrade during the methane oxidation due to the gradual transformation of PdOx to PdO in the oxygen-rich ambiance; however, such degradation is reversible and the activity of a degraded Pd/SiO2 catalyst can be recovered through a redox treatment to regain the PdOx species. This work helps to foster a better understanding of the relationship between the structure and performance of supported Pd catalysts by clarifying the state of active Pd species, which should be beneficial to the design of an active catalyst in lean methane oxidation at low temperature.
Cell–Cell Fusion and the Roads to Novel Properties of Tumor Hybrid Cells
Authors: Sieler Mareike , Weiler Julian , Dittmar Thomas
Published: June 2021

The phenomenon of cancer cell–cell fusion is commonly associated with the origin of more malignant tumor cells exhibiting novel properties, such as increased drug resistance or an enhanced metastatic capacity. However, the whole process of cell–cell fusion is still not well understood and seems to be rather inefficient since only a certain number of (cancer) cells are capable of fusing and only a rather small population of fused tumor hybrids will survive at all. The low survivability of tumor hybrids is attributed to post-fusion processes, which are characterized by the random segregation of mixed parental chromosomes, the induction of aneuploidy and further random chromosomal aberrations and genetic/epigenetic alterations in daughter cells. As post-fusion processes also run in a unique manner in surviving tumor hybrids, the occurrence of novel properties could thus also be a random event, whereby it might be speculated that the tumor microenvironment and its spatial habitats could direct evolving tumor hybrids towards a specific phenotype.
Anti-CD20 Therapy Alters the Protein Signature in Experimental Murine AIH, but Not Exclusively towards Regeneration
Authors: Buitrago-Molina Laura Elisa , Dywicki Janine , Noyan Fatih , Schepergerdes Lena , Pietrek Julia , Lieber Maren , Schlue Jerome , Manns Michael P. , Wedemeyer Heiner , Jaeckel Elmar , Hardtke-Wolenski Matthias
Published: June 2021

Background: Autoimmune hepatitis (AIH) is a chronic autoimmune inflammatory disease that usually requires lifelong immunosuppression. Frequent recurrences after the discontinuation of therapy indicate that intrahepatic immune regulation is not restored by current treatments. Studies of other autoimmune diseases suggest that temporary depletion of B cells can improve disease progression in the long term. Methods: We tested a single administration of anti-CD20 antibodies to reduce B cells and the amount of IgG to induce intrahepatic immune tolerance. We used our experimental murine AIH (emAIH) model and treated the mice with anti-CD20 during the late stage of the disease. Results: After treatment, the mice showed the expected reductions in B cells and serum IgGs, but no improvements in pathology. However, all treated animals showed a highly altered serum protein expression pattern, which was a balance between inflammation and regeneration. Conclusions: In conclusion, anti-CD20 therapy did not produce clinically measurable results because it triggered inflammation, as well as regeneration, at the proteomic level. This finding suggests that anti-CD20 is ineffective as a sole treatment for AIH or emAIH.
Effect of CeO2 on Corrosion Resistance of High-Current Pulsed Electron Beam Treated Pressureless Sintering Al-20SiC Composites
Authors: Sun Yue , Gao Bo , Hu Liang , Li Kui , Zhang Ying
Published: June 2021

In this paper, the effect of rare earth Ce on the corrosion resistance of Al-20SiC composites treated with high-current pulsed electron beams is investigated, and the corresponding corrosion mechanism is proposed. The scanning electron microscope (SEM) results show that cracks arise on the surface of Al-20SiC composites prepared by pressureless sintering. After electron beam treatment, the pores on the surface are reduced because of the filling of Al liquid. After adding CeO2 to Al-20SiC composites, the wettability between Al and SiC phases is improved, thus realizing metallurgical bonding of the two phases, and microcracks generated after HCPEB treatment are significantly eliminated. Glancing X-ray diffraction (GIXRD) results show that after electron beam treatment, aluminum grains tend to grow more favorably with the stable and dense crystal plane of Al(111), thus improving corrosion resistance. The electrochemical test results show that the corrosion current density decreases by one order of magnitude with increase in the number of pulses because of rare earth Ce compared to the initial Al-20SiC composite specimens, indicating that the corrosion resistance of the Al-20SiC-0.3CeO2 composite is improved. This is because rare earth not only eliminates microcracks, but also changes the type of corrosion from localized to uniform, thus improving corrosion resistance. The Al-based composite material modified by electron beam and rare earth has many potential applications and development prospects.
Spatial Low-Rank Tensor Factorization and Unmixing of Hyperspectral Images
Authors: Navas-Auger William , Manian Vidya
Published: June 2021

This work presents a method for hyperspectral image unmixing based on non-negative tensor factorization. While traditional approaches may process spectral information without regard for spatial structures in the dataset, tensor factorization preserves the spectral-spatial relationship which we intend to exploit. We used a rank-(L, L, 1) decomposition, which approximates the original tensor as a sum of R components. Each component is a tensor resulting from the multiplication of a low-rank spatial representation and a spectral vector. Our approach uses spatial factors to identify high abundance areas where pure pixels (endmembers) may lie. Unmixing is done by applying Fully Constrained Least Squares such that abundance maps are produced for each inferred endmember. The results of this method are compared against other approaches based on non-negative matrix and tensor factorization. We observed a significant reduction of spectral angle distance for extracted endmembers and equal or better RMSE for abundance maps as compared with existing benchmarks.
CBAM: A Contextual Model for Network Anomaly Detection
Authors: Clausen Henry , Grov Gudmund , Aspinall David
Published: June 2021

Anomaly-based intrusion detection methods aim to combat the increasing rate of zero-day attacks, however, their success is currently restricted to the detection of high-volume attacks using aggregated traffic features. Recent evaluations show that the current anomaly-based network intrusion detection methods fail to reliably detect remote access attacks. These are smaller in volume and often only stand out when compared to their surroundings. Currently, anomaly methods try to detect access attack events mainly as point anomalies and neglect the context they appear in. We present and examine a contextual bidirectional anomaly model (CBAM) based on deep LSTM-networks that is specifically designed to detect such attacks as contextual network anomalies. The model efficiently learns short-term sequential patterns in network flows as conditional event probabilities. Access attacks frequently break these patterns when exploiting vulnerabilities, and can thus be detected as contextual anomalies. We evaluated CBAM on an assembly of three datasets that provide both representative network access attacks, real-life traffic over a long timespan, and traffic from a real-world red-team attack. We contend that this assembly is closer to a potential deployment environment than current NIDS benchmark datasets. We show that, by building a deep model, we are able to reduce the false positive rate to 0.16% while effectively detecting six out of seven access attacks, which is significantly lower than the operational range of other methods. We further demonstrate that short-term flow structures remain stable over long periods of time, making the CBAM robust against concept drift.
Risk of Invasive Lupinus polyphyllus Seed Survival in Biomass Treatment Processes
Authors: Hassani Marjaana , Vallius Elisa , Rasi Saija , Sormunen Kai
Published: June 2021

Invasive plant species threaten native species and habitats causing ecologic, economic and social burden. When creating climate friendly solutions by utilizing plant biomasses in biogas and fertilizer production, safety should be ensured concerning the use of residues. This study concentrates on the treatment of biomasses containing invasive plant material by tunnel and windrow composting, and by farm-scale and laboratory-scale anaerobic digestion (AD) in mesophilic conditions. Germination of the nationally settled and harmful invasive species Lupinus polyphyllus Lindl. was investigated after these processes. In addition, the role of the conditions found in the processes that destroyed seeds were studied, such as the time of exposure, temperature and static pressure. Dormant seeds are well protected against harsh conditions and can survive through various stress factors, but also become vulnerable as more factors are combined and time of exposure is extended. Our results suggest that the risks involved for the utilization of harmful invasive species increase with mesophilic temperatures and single treatments if the processing conditions are not stabile. One-month treatment with windrow composting showed a high risk for dormant seeds of L. polyphyllus seeds to survive, whereby extending the processing time reduced it substantially. Hard coated seeds can thus be broken with a combination of thermophilic temperatures, moisture and static pressure.
Mediterranean Red Macro Algae Mats as Habitat for High Abundances of Serpulid Polychaetes
Authors: Rossbach Felix I. , Casoli Edoardo , Beck Milan , Wild Christian
Published: June 2021

The Mediterranean Sea harbors more than 17,000 eukaryotic marine species, with several ecosystems recognized as biodiversity hotspots, such as Posidonia oceanica meadows. Recent research indicates that benthic mats formed by the fleshy red alga Phyllophora crispa are also associated with high species richness. Among key groups found in these mats are sessile polychaetes, which live as epiphytes on the red algae thalli. Knowledge of abundance, species richness, and spatial variation of polychaetes associated with these habitats is still scarce. We carried out a comparative assessment focusing on serpulid polychaetes within samples from P. crispa mats and neighboring P. oceanica meadows at six different sampling sites around Giglio Island (Tyrrhenian Sea, Italy). A total of 17 serpulid taxa were identified. The abundance of serpulids (5665 individuals m−2 of P. crispa mat) were similar to neighboring P. oceanica meadows (2304 individuals m−2 leaves and 5890 individuals m−2 shoots). The number of serpulid taxa was significantly higher in P. crispa mats (average 6.63 ± 1.32 taxa) compared to P. oceanica beds (average 1.56 ± 0.63 and 1.84 ± 1.04 taxa in leaves and shoots, respectively). Within habitat type, there were no significant differences in species richness between sites. The most abundant species found was Josephella marenzelleri (61% of individuals), while Vermiliopsis spp. and Bathyvermilia sp. were exclusively found in P. crispa samples. Our results highlight that P. crispa mats host an exceptional diversity and that these habitats should be included in conservation strategies. Further research should focus on the significance of other important taxonomic groups within these mats and evaluate the distribution of P. crispa in different regions of the Mediterranean Sea.
The Evoked Potential Score for SSEP and BAEP—A Prognostic Marker for the Long-Term Neurological Outcome in Patients after Poor-Grade Subarachnoid Hemorrhage
Authors: Wadiura Lisa I. , Herta Johannes , Mischkulnig Mario , Hirschmann Dorian , Borkovec Martin , Hosmann Arthur , Reinprecht Andrea
Published: June 2021

Objective: Evoked potentials are widely used in comatose patients to evaluate neurological function; however, prognostic relevance in patients after SAH is barely investigated. Therefore, we aimed to investigate the prognostic value of the proposed Evoked Potential Score (EPS) for somatosensory (SSEP) and brainstem auditory evoked potentials (BAEP) on the neurological outcome in patients after poor-grade SAH. Methods: We retrospectively analyzed patients after poor grade SAH (Hunt and Hess (HH) grade IV and V) that were admitted to the ICU at the Department of Neurosurgery, MUV, between 2014 and 2017. Measurements of SSEP and BAEP were evaluated separately as well as in a combined model, using the EPS at admission and before ventilator weaning and correlated with the grade of the modified ranking scale at the last available follow up. Results: In total, 48 patients after SAH HH IV/V were included in this study. The EPS for SSEP at admission (p = 0.007) and both the EPS for SSEP (p = <0.0001) and BAEP (p = 0.036) before ventilator weaning were significant prognostic markers for neurological improvement at a mean follow-up period of 14.1 months. In addition, the combined model of the EPS for SSEP/BAEP performed as a prognostic marker for neurological improvement (“at admission” p = 0.007; “before ventilator weaning” p < 0.001). Conclusions: In the first series to date we found a high prognostic significance for the EPS as a combined model, as well as a separate analysis for SSEP and BAEP in patients after SAH IV and V. In the future, these findings potentially support physicians in ethically challenging decision-making processes and in advice for patients’ families under consideration of an individual evaluation of each patient.
Deep Learning-Based Post-Processing of Real-Time MRI to Assess and Quantify Dynamic Wrist Movement in Health and Disease
Authors: Radke Karl Ludger , Wollschläger Lena Marie , Nebelung Sven , Abrar Daniel Benjamin , Schleich Christoph , Boschheidgen Matthias , Frenken Miriam , Schock Justus , Klee Dirk , Frahm Jens , Antoch Gerald , Thelen Simon , Wittsack Hans-Jörg , Müller-Lutz Anja
Published: June 2021

While morphologic magnetic resonance imaging (MRI) is the imaging modality of choice for the evaluation of ligamentous wrist injuries, it is merely static and incapable of diagnosing dynamic wrist instability. Based on real-time MRI and algorithm-based image post-processing in terms of convolutional neural networks (CNNs), this study aims to develop and validate an automatic technique to quantify wrist movement. A total of 56 bilateral wrists (28 healthy volunteers) were imaged during continuous and alternating maximum ulnar and radial abduction. Following CNN-based automatic segmentations of carpal bone contours, scapholunate and lunotriquetral gap widths were quantified based on dedicated algorithms and as a function of wrist position. Automatic segmentations were in excellent agreement with manual reference segmentations performed by two radiologists as indicated by Dice similarity coefficients of 0.96 ± 0.02 and consistent and unskewed Bland–Altman plots. Clinical applicability of the framework was assessed in a patient with diagnosed scapholunate ligament injury. Considerable increases in scapholunate gap widths across the range-of-motion were found. In conclusion, the combination of real-time wrist MRI and the present framework provides a powerful diagnostic tool for dynamic assessment of wrist function and, if confirmed in clinical trials, dynamic carpal instability that may elude static assessment using clinical-standard imaging modalities.
Using Videos in Blended E-Learning for a Structural Steel Design Course
Authors: EL-Ariss Bilal , Zaneldin Essam , Ahmed Waleed
Published: June 2021

Conventional methods of teaching structural engineering topics focus on face-to-face delivery of course materials. This study shows that using video-based e-learning in delivering an undergraduate Structural Steel Design course satisfactorily achieved most of the course learning outcomes. Video-based e-learning with animations and simulations gives students a profound understanding of the course intricate design materials. To gauge the effectiveness of video-based e-learning of the course, an online evaluation was conducted by sixty-eight undergraduate students at the United Arab Emirates University using Blackboard. The evaluation consisted of an online survey that was accessible by students who took the structural steel design course in the academic year 2019 using instructional videos provided to them as Quick Response (QR)-codes. The structural steel design course has six learning outcomes (CLOs), and the performance of students in the six CLOs was compared with that of students who took the same course in the academic year 2018 using the traditional face-to-face lecturing method. The survey data was statistically analyzed, and the results revealed that students’ performance improved, and most of the CLOs were attained. Video-based e-learning with animations resulted in better learning outcomes compared to face-to-face lecturing. Accessing the course instruction videos anytime and anywhere is one of the remarkable benefits to the students studying through the e-learning approach.
Ring-Oscillator with Multiple Transconductors for Linear Analog-to-Digital Conversion
Authors: Alvero-Gonzalez Leidy Mabel , Medina Victor , Kampus Vahur , Paton Susana , Hernandez Luis , Gutierrez Eric
Published: June 2021

This paper proposes a new circuit-based approach to mitigate nonlinearity in open-loop ring-oscillator-based analog-to-digital converters (ADCs). The approach consists of driving a current-controlled oscillator (CCO) with several transconductors connected in parallel with different bias conditions. The current injected into the oscillator can then be properly sized to linearize the oscillator, performing the inverse current-to-frequency function. To evaluate the approach, a circuit example has been designed in a 65-nm CMOS process, leading to a more than 3-ENOB enhancement in simulation for a high-swing differential input voltage signal of 800-mVpp, with considerable less complex design and lower power and expected area in comparison to state-of-the-art circuit based solutions. The architecture has also been checked against PVT and mismatch variations, proving to be highly robust, requiring only very simple calibration techniques. The solution is especially suitable for high-bandwidth (tens of MHz) medium-resolution applications (10–12 ENOBs), such as 5G or Internet-of-Things (IoT) devices.
Improving Transient Behavior of a Brushless Doubly Fed Induction Generator through Reactive Current Control of Grid-Side Converter
Authors: Memon Ahsanullah , Mustafa Mohd Wazir , Aman Muhammad Naveed , Hafeez Abdul , Ullah Mukhtar
Published: June 2021

Brushless doubly-fed induction generators have higher reliability, making them an attractive choice for not only offshore applications but also for remote locations. These generators are composed of two back-to-back voltage source converters, a grid side converter and a rotor side converter. Existing techniques use the rotor side converter for reactive current control; however, it is more suitable for stabilizing steady state behavior. In order to stabilize the voltage fluctuations at the point of common coupling (PCC) due to sudden inductive load introduction, the grid side converter may be a better choice due to faster response and higher control bandwidth. Therefore, this paper proposes a control scheme for the grid side converter to suppress the PCC voltage fluctuations when a large inductive load is suddenly connected. The proposed technique is based on an analytical model of the transient behavior of the voltage drop at the PCC. The analysis shows that reactive current control using the grid side converter introduces a double fundamental frequency component to the PCC voltage. To block this harmonic, we designed a notch filter. The simulation results in Matlab/Simulink show that the proposed technique can not only significantly reduce the voltage drop but also results in an 82% reduction in voltage distortion at the PCC.
SOGI-FLL Grid Frequency Monitoring with an Error-Based Algorithm for a Better Response in Face of Voltage Sag and Swell Faults
Authors: Abdali Nejad Sajad , Matas José , Elmariachet Jordi , Martín Helena , de la Hoz Jordi
Published: June 2021

The SOGI-FLL (second-order generalized-integrator frequency-locked-loop) is a well-known and simple adaptive filter that allows estimation of the parameters of the grid voltage with a small computational burden. However, this structure has shown to be sensitive to the events of voltage sags and swell faults, especially to voltage sags that deeply distort the estimated frequency. In this paper an algorithm is proposed to face the fault that modifies the SOGI-FLLs gains in order to achieve a better transient response with a reduced perturbation in the estimated frequency. The algorithm uses the SOGI’s instantaneous and absolute error to detect the fault and change the SOGI-FLL gains during the fault. Moreover, the average of the absolute error is used for returning to normal operating conditions. The average value is obtained by means of a single low pass filter (LPF). The approach is easy to implement and represents a low computational burden for being implemented into a digital processor. The performance is evaluated by using simulations and real-time Typhoon Hardware in the Loop (HIL) results.
The Economic Aspect of Using Different Plug-In Hybrid Driving Techniques in Urban Conditions
Authors: Wróblewski Piotr , Kupiec Jerzy , Drożdż Wojciech , Lewicki Wojciech , Jaworski Jarosław
Published: June 2021

Plug-in hybrids (PHEV) have become popular due to zero-emission driving, e.g., in urban areas, and using an internal combustion engine on longer distances. Energy consumption by the PHEV depends on many factors which can be either dependent or independent of the driver. The article examines how the driver can use the vehicle’s capabilities to influence its wear. Determining the optimal driving technique, due to the adopted nature of the timetable, is the basic variable that determines the profitability of using a given drive system. Four driving techniques have been selected to determine which one can offer the largest advantages. A vehicle-dedicated application has recorded the drivetrain performance on a predetermined route through an urban area. The analysis of results has demonstrated which of the driving techniques provides measurable effects in terms of reduced energy consumption and the shortest travelling time. The study shows longitudinal acceleration and torque generated by the electric drive. The information included in the study can help any PHEV user reduce the operating cost by applying an appropriate driving technique. The proposed research introduces the possibilities of assessing the influence of the driving style on energy consumption. The innovative side of this research is the observation of stochastic phenomena that are difficult to detect when using approximation modelling.
A Study of Hot Climate Low-Cost Low-Energy Eco-Friendly Building Envelope with Embedded Phase Change Material
Authors: Rehman Atiq Ur , Ghafoor Nouman , Sheikh Shakil R. , Kausar Zareena , Rauf Fawad , Sher Farooq , Shah Muhammad Faizan , Yaqoob Haseeb
Published: June 2021

The generation and use of energy are significant contributors to CO2 emissions. Globally, approximately 30% to 40% of all energy consumption can be directly or indirectly linked to buildings. Nearly half of energy usage in buildings is linked to maintaining the thermal comfort of the inhabitants. Therefore, finding solutions that are not only technically but also economically feasible is of utmost importance. Though much research has been conducted to address this issue, most solutions are still costly for developing countries to implement practically. This study endeavors to find a less expensive yet straightforward methodology to achieve thermal comfort while conserving energy. This study takes a broader view of multiple habitat-related CO2 emission issues in developing regions and describes a hybrid solution to address them. New technologies and innovative concepts are being globally examined to benefit from the considerable potential of PCMs and their role in thermal energy storage (TES) applications for buildings. The current study numerically investigates the thermal response of a hybrid building envelope consisting of PCM and local organic waste materials for low-cost low-energy buildings. The local organic waste materials used are those whose disposal is usually done by burning, resulting in an immense amount of greenhouse gases. In the first phase, different waste materials are characterized to determine their thermophysical properties. In the second phase, a low-cost, commonly available PCM calcium chloride hexahydrate, CaCl2·6H2O, is integrated with a brick and corn husk wall to enhance the thermal storage in the building envelope to minimize energy consumption. Temperature distribution plots are primarily used for analysis. The results show a marked improvement in thermal comfort by maintaining a maximum indoor temperature of 27 °C when construction is performed with a 6% corn husk composite material embedded with the PCM, while under similar conditions, the standard brick construction maintained a 31 °C indoor temperature. It is concluded that the integration of the PCM layer with the corn husk wall provides an adequate solution for low-cost and low-energy buildings.
Hybrid Control of Grid-Feeding and Fuzzy Logic Fault Detection in Solving Voltage Dynamic Problem within the Malaysian Distribution Network
Authors: Hoe Ong Kam , Ramasamy Agileswari K. , Yin Lee Jun , Verayiah Renuga , Marsadek Marayati Binti , Abdillah Muhammad
Published: June 2021

The stochastic behavior of PV together with high PV penetration have given rise to power quality concerns involving voltage dynamic issues such as undervoltage, overvoltage, sag and swell. To ensure the grid’s stability, various methods have been practiced such as a proper sizing of the grid lines and the installation of power quality compensation equipment. However, these measures often require high costs and high control complexity due to additional equipment being involved such as multiple transformers and inverters. Moreover, the current available reactive power compensation equipment has a lesser impact on distribution level networks. Therefore, this work proposes a hybrid control of grid-feeding mode and energy storage with Direct Current (DC) fault detection scheme utilizing fuzzy control to mitigate high PV penetration problems, PV intermittency and faults via active power compensation to maintain the system’s voltage within its nominal range. This hybrid control works on two mode of operations: strategic power dispatch by the grid-feeding mode to solve under and overvoltage caused by inconsistent PV generation. Meanwhile, the utilization of fuzzy control aims to solve PV intermittency and line faults. The novel hybrid control has proven its capability to solve voltage dynamic problems caused by high PV penetration, intermittency and faults in the network within a shorter timeframe.
Online Measurement Error Detection for the ElectronicTransformer in a Smart Grid
Authors: Xiong Gu , Przystupa Krzysztof , Teng Yao , Xue Wang , Huan Wang , Feng Zhou , Qiong Xiang , Wang Chunzhi , Skowron Mikołaj , Kochan Orest , Beshley Mykola
Published: June 2021

With the development of smart power grids, electronic transformers have been widely used to monitor the online status of power grids. However, electronic transformers have the drawback of poor long-term stability, leading to a requirement for frequent measurement. Aiming to monitor the online status frequently and conveniently, we proposed an attention mechanism-optimized Seq2Seq network to predict the error state of transformers, which combines an attention mechanism, Seq2Seq network, and bidirectional long short-term memory networks to mine the sequential information from online monitoring data of electronic transformers. We implemented the proposed method on the monitoring data of electronic transformers in a certain electric field. Experiments showed that our proposed attention mechanism-optimized Seq2Seq network has high accuracy in the aspect of error prediction.
Experimental Investigation of Air–Fuel Mixing Effects on Flame Characteristics in a Direct fired Burner
Authors: Lee Cheolwoo , Kim Insu , Hong Junggoo
Published: June 2021

The length and pattern of air–fuel mixing plays a significant role in the uniformity, flame temperature, and emission characteristics, which can lead to a superior product quality in a non-oxidizing direct fired burner for a cold-rolled steel plate furnace. In this study, a diffusion-flame-type burner and partially-premixed-type burner were experimentally investigated to understand their effects on flame shape, flame temperature, and exhaust gas characteristics. With this aim, fuel nozzle size, nozzle hole number, fuel injection angle, and mixing distance of fuel and air were varied during the experiments. Computational fluid dynamics simulations were also performed to investigate the air–fuel mixing state for a nozzle-mixed burner and a partially-premixed burner. The results show that the flame temperature of the partially-premixed burner increases by up to 26 °C on average compared to that of the nozzle-mixed burner. It is also shown that the mixing distance plays an important role in the flame temperature of the partially-premixed burner. In addition, the residual oxygen concentration and volume ratio of CO/CO2 in the flue gas of the partially-premixed burner exhibit lower concentrations compared to those of the diffusion flame burner.
Methodological Proposal for the Assessment Potential of Pumped Hydropower Energy Storage: Case of Gran Canaria Island
Authors: Torres-Herrera Hilario , Lozano-Medina Alexis
Published: June 2021

The pumped hydropower energy storage (PHES) assessments carried out so far have been focused on large water bodies obtained from global or restricted-use databases, or, on the other hand, on the application of methodologies to specific areas focusing on the detection of dams. In addition, many assessments do not include data optimization, or include it at the end of the process and are subject to the prior application of restrictions, often stipulated with subjective criteria. The aim of this article is to design a universal and easily applicable methodology for the assessment of viable PHES potential, which provides immediate and reliable results to assist in the energy planning of a given territory. It is classified in ravine basins, including an optimization before using the restrictions. The island of Gran Canaria is taken as the territory of application, whose density of dams is the highest in the world and whose share of hydroelectric energy is, at present, null; besides, no PHES studies have been carried out. The results show that the PHES potential in Gran Canaria is 5996 MWh after applying the optimization and all technical constraints. If all environmental constraints were rigorously applied, the island would have no possible pairing. The results demonstrate the importance of tailoring the restrictions to each particular territory.
Production of High Purity Biosurfactants Using Heavy Oil Residues as Carbon Source
Authors: Mandalenaki Athina , Kalogerakis Nicolas , Antoniou Eleftheria
Published: June 2021

Typically, oil pollution cleanup procedures following first response actions include dispersion. Crude oil is biodegradable, and its bioavailability can be increased when dispersed into very fine droplets by means of chemical surfactants. Although their use is widely spread in many applications, the latter may prove toxic, depending on the extent of use. The use of biological means, such as bioremediation and biosurfactants, has emerged over the past years as a very promising ‘green’ alternative technology. Biosurfactants (BSs) are amphiphilic molecules produced by microorganisms during biodegradation, thus increasing the bioavailability of the organic pollutants. It is their biodegradability and low toxicity that render BSs as a very promising alternative to the synthetic ones. Alcanivorax borkumensis SK2 strain ability to produce BSs, without any impurities from the substrate, was investigated. The biosurfactant production was scaled up by means of a sequencing batch reactor (SBR) and a heavy oil residue substrate as the carbon source. The product is free from substrate impurities, and its efficiency is tested on oil bioremediation in the marine environment. The product’s dispersion efficiency was determined by the baffled flask test. The production method proposed can have a significant impact to the market, given the ever-increasing demand for ecologically friendly, reliable, commercially viable and economically competitive environmental cleanup techniques.
Assessment of the Influence of Road Infrastructure Parameters on the Behaviour of Drivers and Pedestrians in Pedestrian Crossing Areas
Authors: Budzynski Marcin , Gobis Anna , Guminska Lucyna , Jelinski Lukasz , Kiec Mariusz , Tomczuk Piotr
Published: June 2021

Pedestrians are participants and, most likely, fatalities in every third road traffic accident in Poland. Over 30% of all fatalities on Polish roads are pedestrians. Accidents with pedestrians are very often the result of various factors related to the infrastructure and behaviour of pedestrians and drivers. The objective of the work was to assess driver and pedestrian behaviour in pedestrian crossing areas. The research also served as a pilot study for similar work to be conducted across Poland, and constituted the basis for monitoring the behaviour of road users in the area of pedestrian crossings. Parameters which must be analysed were identified on the basis of field studies. Principles of selecting test sites were adopted, and measurement methods for pedestrian crossing areas are presented. The influence of the location of the selected test cross-section infrastructure parameters on the behaviour of road users in pedestrian crossing areas is demonstrated. The results of the study will be used as a basis for new solutions involving pedestrian crossing infrastructure designed to improve pedestrian safety. The results were also used in formulating new regulations for the design and maintenance of pedestrian crossings and recommendations for road safety auditors.
“He Just Doesn’t Want to Get Out of the Chair and Do It”: The Impact of Apathy in People with Dementia on Their Carers
Authors: Chang Chern Yi Marybeth , Baber Waqaar , Dening Tom , Yates Jennifer
Published: June 2021

Apathy, defined as a lack of motivation, is a prevalent and persistent behavioural and psychological symptom of dementia. Limited research suggests that apathy is associated with increased carer burden, but there are no studies investigating carers’ subjective experiences of apathy. This study aimed to fill this gap and explore the lived experience of apathy in dementia from the perspectives of the people with dementia and their carers. This article reports on the carers’ perspectives. Six dyads of people with dementia and carers participated in semi-structured interviews, which were analysed using interpretative phenomenological analysis. Three superordinate themes were identified: (1) achieving a balance of conflicting emotions—the challenges of apathy led to feelings of guilt, acceptance, and frustration; (2) new roles imposed by caring, which involved taking on new responsibilities and promoting remaining interests of person with dementia; and (3) having a life of one’s own—coping with apathy by talking to others, and spending time away from the caring role. This study highlighted that carers are caught in a struggle between wanting to involve the person with dementia in decisions and finding that they cannot if they want to overcome the hurdle of apathy. Implications of this study suggest that a wider understanding of apathy at a societal level could lead to the provision of a helpful forum for carers to share their experiences.
A Complementary Intervention to Promote Wellbeing and Stress Management for Early Career Teachers
Authors: Hepburn Stevie-Jae , Carroll Annemaree , McCuaig-Holcroft Louise
Published: June 2021

The educational climate and culture in our schools present a variety of environmental (contextual) factors that influence teacher wellbeing, job satisfaction, and work-related stress. The magnitude of contextual factors cannot be ignored, and directing attention towards the environment teachers face daily is essential. Primary (organisational)-level interventions are documented in organisational health and wellbeing literature; however, to provide teachers with stress management strategies for promoting wellbeing, attention must also be directed towards secondary (individual)-level interventions. The present study addressed the issue of stress management techniques for early career teachers (n = 24) and aimed to contribute to the research surrounding complementary interventions (CIs) for educators. The intervention was designed to include strategies that operated through cognitive and physiological mechanisms that regulated the stress response and increased awareness of behaviours, emotions, and reactivity. The self-report measures included perceived stress, attention awareness, subjective wellbeing, burnout, and job-related affective wellbeing. The results indicated a statistically significant decrease in perceived stress and increases in attention awareness and subjective wellbeing. The salivary cortisol levels (waking and resting) decreased from baseline to week 6, and the pre- and post-session salivary cortisol levels indicated an immediate decrease in cortisol for weeks 4 to 6.
Exploring Factors Impacting on the Lane Choice of Riders of Non-Motorized Vehicles at Exit Legs of Signalized At-Grade Intersections
Authors: Zhang Guoqiang , Zhou Qiqi , Chen Jun
Published: June 2021

For most signalized at-grade intersections, exclusive lanes for non-motorized vehicles have been applied to improve the level of service, capacity and safety of both motorized vehicles and non-motorized vehicles. However, because of various factors, riders of non-motorized vehicles have been observed using lanes for motorized vehicles instead of lanes for non-motorized vehicles, which usually negatively influences the performance of signalized intersections and sometimes may cause serious problems such as traffic congestion and accidents. The objective of this paper is to explore factors influencing the lane choice of riders of non-motorized vehicles at exit legs of signalized at-grade intersections and develop a prediction model for riders’ lane choice. Data concerning the lane choice of riders of non-motorized vehicles and other impacting factors were collected at exit legs of four typical signalized at-grade intersections. Applying binary logistic regression, a probability prediction model was developed to explain how various factors influence the lane choice of riders of non-motorized vehicles. The prediction model indicates that female riders of non-motorized vehicles have a higher probability of choosing the lane for non-motorized vehicles than male riders. Compared with riders of non-motorized vehicles powered by electricity, riders of traditional man-powered bicycles are more likely to choose the lane for non-motorized vehicles. Right-turning riders of non-motorized vehicles are more likely to choose the lane for non-motorized vehicles than straight-going riders, who in turn, are more likely to choose the lane for non-motorized vehicles than left-turning riders. Decreasing the volume of non-motorized vehicles, increasing the volume of motorized vehicles, and widening the lane for non-motorized vehicles will increase the probability of the correct choice of lane for non-motorized vehicles. The predictions of the model are in good agreement with the observed facts. The model is meaningful for guidance on the design and management of signalized at-grade intersections.
Identifying Patterns of Symptom Distress in Pregnant Women: A Pilot Study
Authors: Lee Ching-Fang , Wen Fur-Hsing , Hsiung Yvonne , Huang Jian-Pei , Chang Chun-Wei , Chen Hung-Hui
Published: June 2021

During pregnancy, a woman’s enlarged uterus and the developing fetus lead to symptom distress; in turn, physical and psychological aspects of symptom distress are often associated with adverse prenatal and birth outcomes. This study aimed to identify the trends in the trajectory of these symptoms. This longitudinal study recruited 95 pregnant women, with a mean age of 32 years, from the prenatal wards of two teaching hospitals in northern Taiwan. Symptom distress was measured by a 22-item scale related to pregnancy-induced symptoms. The follow-up measurements began during the first trimester and were taken every two to four weeks until childbirth. More than half of the pregnant women experienced symptom distress manifested in a pattern depicted to be “Decreased then Increased” (56.8%). Other noticeable patterns were “Continuously Increased” (28.4%), “Increased then Decreased” (10.5%) and “Continuously Decreased” (4.2%), respectively. It is worth noting that most pregnant women recorded a transit and increase in their symptom distress, revealed by their total scores, at the second trimester (mean 22.02 weeks) of pregnancy. The participants’ major pregnancy-related distress symptoms were physical and included fatigue, frequent urination, lower back pain, and difficulty sleeping. The mean scores for individual symptoms ranged from 2.32 to 3.61 and were below the “moderately distressful” level. This study provides evidence that could be used to predict women’s pregnancy-related symptom distress and help healthcare providers implement timely interventions to improve prenatal care.