bluuebunny/crossref_metadata_2025 huggingface dataset:
Real-World Evaluation of Universal Germline Screening for Cancer Treatment-Relevant Pharmacogenes
Authors: Hutchcraft Megan L. , Lin Nan , Zhang Shulin , Sears Catherine , Zacholski Kyle , Belcher Elizabeth A. , Durbin Eric B. , Villano John L. , Cavnar Michael J. , Arnold Susanne M. , Ueland Frederick R. , Kolesar Jill M.
Published: September 2021

The purpose of this study was to determine the frequency of clinically actionable treatment-relevant germline pharmacogenomic variants in patients with cancer and assess the real-world clinical utility of universal screening using whole-exome sequencing in this population. Cancer patients underwent research-grade germline whole-exome sequencing as a component of sequencing for somatic variants. Analysis in a clinical bioinformatics pipeline identified clinically actionable pharmacogenomic variants. Clinical Pharmacogenetics Implementation Consortium guidelines defined clinical actionability. We assessed clinical utility by reviewing electronic health records to determine the frequency of patients receiving pharmacogenomically actionable anti-cancer agents and associated outcomes. This observational study evaluated 291 patients with cancer. More than 90% carried any clinically relevant pharmacogenetic variant. At least one disease-relevant variant impacting anti-cancer agents was identified in 26.5% (77/291). Nine patients with toxicity-associated pharmacogenomic variants were treated with a relevant medication: seven UGT1A1 intermediate metabolizers were treated with irinotecan, one intermediate DPYD metabolizer was treated with 5-fluorouracil, and one TPMT poor metabolizer was treated with mercaptopurine. These individuals were more likely to experience treatment-associated toxicities than their wild-type counterparts (p = 0.0567). One UGT1A1 heterozygote died after a single dose of irinotecan due to irinotecan-related adverse effects. Identifying germline pharmacogenomic variants was feasible using whole-exome sequencing. Actionable pharmacogenetic variants are common and relevant to patients undergoing cancer treatment. Universal pharmacogenomic screening can be performed using whole-exome sequencing data originally obtained for quality control purposes and could be considered for patients who are candidates for irinotecan, 5-fluorouracil, capecitabine, and mercaptopurine.
The Translocator Protein (TSPO) Genetic Polymorphism A147T Is Associated with Worse Survival in Male Glioblastoma Patients
Authors: Troike Katie M. , Acanda de la Rocha Arlet M. , Alban Tyler J. , Grabowski Matthew M. , Otvos Balint , Cioffi Gino , Waite Kristin A. , Barnholtz Sloan Jill S. , Lathia Justin D. , Guilarte Tomás R. , Azzam Diana J.
Published: September 2021

Glioblastoma (GBM) is the most common primary brain tumor in adults, with few available therapies and a five-year survival rate of 7.2%. Hence, strategies for improving GBM prognosis are urgently needed. The translocator protein 18kDa (TSPO) plays crucial roles in essential mitochondria-based physiological processes and is a validated biomarker of neuroinflammation, which is implicated in GBM progression. The TSPO gene has a germline single nucleotide polymorphism, rs6971, which is the most common SNP in the Caucasian population. High TSPO gene expression is associated with reduced survival in GBM patients; however, the relation between the most frequent TSPO genetic variant and GBM pathogenesis is not known. The present study retrospectively analyzed the correlation of the TSPO polymorphic variant rs6971 with overall and progression-free survival in GBM patients using three independent cohorts. TSPO rs6971 polymorphism was significantly associated with shorter overall survival and progression-free survival in male GBM patients but not in females in one large cohort of 441 patients. We observed similar trends in two other independent cohorts. These observations suggest that the TSPO rs6971 polymorphism could be a significant predictor of poor prognosis in GBM, with a potential for use as a prognosis biomarker in GBM patients. These results reveal for the first time a biological sex-specific relation between rs6971 TSPO polymorphism and GBM.
Low-Temperature Hydrogenation of Toluene Using an Iron-Promoted Molybdenum Carbide Catalyst
Authors: Zhou Song , Liu Xi , Xu Jian , Zhang Hui , Liu Xiaosong , Li Pengcheng , Wen Xiaodong , Yang Yong , Li Yongwang
Published: September 2021

As an alternative to noble metal hydrogenation catalysts, pure molybdenum carbide displays unsatisfactory catalytic activity for arene hydrogenation. Precious metals such as palladium, platinum, and gold are widely used as additives to enhance the catalytic activities of molybdenum carbide, which severely limits its potential applications in industry. In this paper, iron-promoted molybdenum carbide was prepared and characterized by various techniques, including in situ XRD, synchrotron-based XPS and TEM. while the influence of Fe addition on catalytic performance for toluene hydrogenation was also studied. The experimental data disclose that a small amount of Fe doping strongly enhances catalytic stability in toluene hydrogenation, but the catalytic performance drops rapidly with higher loading amounts of Fe.
Sustainable Exploitation of Residual Cynara cardunculus L. to Levulinic Acid and n-Butyl Levulinate
Authors: Raspolli Galletti Anna Maria , Licursi Domenico , Ciorba Serena , Di Fidio Nicola , Coccia Valentina , Cotana Franco , Antonetti Claudia
Published: September 2021

Hydrolysis and butanolysis of lignocellulosic biomass are efficient routes to produce two valuable bio-based platform chemicals, levulinic acid and n-butyl levulinate, which find increasing applications in the field of biofuels and for the synthesis of intermediates for chemical and pharmaceutical industries, food additives, surfactants, solvents and polymers. In this research, the acid-catalyzed hydrolysis of the waste residue of Cynara cardunculus L. (cardoon), remaining after seed removal for oil exploitation, was investigated. The cardoon residue was employed as-received and after a steam-explosion treatment which causes an enrichment in cellulose. The effects of the main reaction parameters, such as catalyst type and loading, reaction time, temperature and heating methodology, on the hydrolysis process were assessed. Levulinic acid molar yields up to about 50 mol % with levulinic acid concentrations of 62.1 g/L were reached. Moreover, the one-pot butanolysis of the steam-exploded cardoon with the bio-alcohol n-butanol was investigated, demonstrating the direct production of n-butyl levulinate with good yield, up to 42.5 mol %. These results demonstrate that such residual biomass represent a promising feedstock for the sustainable production of levulinic acid and n-butyl levulinate, opening the way to the complete exploitation of this crop.
Elongational Stresses and Cells
Authors: Foster Kylie M. , Papavassiliou Dimitrios V. , O’Rear Edgar A.
Published: September 2021

Fluid forces and their effects on cells have been researched for quite some time, especially in the realm of biology and medicine. Shear forces have been the primary emphasis, often attributed as being the main source of cell deformation/damage in devices like prosthetic heart valves and artificial organs. Less well understood and studied are extensional stresses which are often found in such devices, in bioreactors, and in normal blood circulation. Several microfluidic channels utilizing hyperbolic, abrupt, or tapered constrictions and cross-flow geometries, have been used to isolate the effects of extensional flow. Under such flow cell deformations, erythrocytes, leukocytes, and a variety of other cell types have been examined. Results suggest that extensional stresses cause larger deformation than shear stresses of the same magnitude. This has further implications in assessing cell injury from mechanical forces in artificial organs and bioreactors. The cells’ greater sensitivity to extensional stress has found utility in mechanophenotyping devices, which have been successfully used to identify pathologies that affect cell deformability. Further application outside of biology includes disrupting cells for increased food product stability and harvesting macromolecules for biofuel. The effects of extensional stresses on cells remains an area meriting further study.
Lipid Polymorphism of the Subchloroplast—Granum and Stroma Thylakoid Membrane—Particles. I. 31P-NMR Spectroscopy
Authors: Dlouhý Ondřej , Javornik Uroš , Zsiros Ottó , Šket Primož , Karlický Václav , Špunda Vladimír , Plavec Janez , Garab Győző
Published: September 2021

Build-up of the energized state of thylakoid membranes and the synthesis of ATP are warranted by organizing their bulk lipids into a bilayer. However, the major lipid species of these membranes, monogalactosyldiacylglycerol, is a non-bilayer lipid. It has also been documented that fully functional thylakoid membranes, in addition to the bilayer, contain an inverted hexagonal (HII) phase and two isotropic phases. To shed light on the origin of these non-lamellar phases, we performed 31P-NMR spectroscopy experiments on sub-chloroplast particles of spinach: stacked, granum and unstacked, stroma thylakoid membranes. These membranes exhibited similar lipid polymorphism as the whole thylakoids. Saturation transfer experiments, applying saturating pulses at characteristic frequencies at 5 °C, provided evidence for distinct lipid phases—with component spectra very similar to those derived from mathematical deconvolution of the 31P-NMR spectra. Wheat-germ lipase treatment of samples selectively eliminated the phases exhibiting sharp isotropic peaks, suggesting easier accessibility of these lipids compared to the bilayer and the HII phases. Gradually increasing lipid exchanges were observed between the bilayer and the two isotropic phases upon gradually elevating the temperature from 5 to 35 °C, suggesting close connections between these lipid phases. Data concerning the identity and structural and functional roles of different lipid phases will be presented in the accompanying paper.
Co-Ordination of Mucosal B Cell and CD8 T Cell Memory by Tissue-Resident CD4 Helper T Cells
Authors: Son Young Min , Sun Jie
Published: September 2021

Adaptive cellular immunity plays a major role in clearing microbial invasion of mucosal tissues in mammals. Following the clearance of primary pathogens, memory lymphocytes are established both systemically and locally at pathogen entry sites. Recently, resident memory CD8 T and B cells (TRM and BRM respectively), which are parked mainly in non-lymphoid mucosal tissues, were characterized and demonstrated to be essential for protection against secondary microbial invasion. Here we reviewed the current understanding of the cellular and molecular cues regulating CD8 TRM and BRM development, maintenance and function. We focused particularly on elucidating the role of a novel tissue-resident helper T (TRH) cell population in assisting TRM and BRM responses in the respiratory mucosa following viral infection. Finally, we argue that the promotion of TRH responses by future mucosal vaccines would be key to the development of successful universal influenza or coronavirus vaccines, providing long-lasting immunity against a broad spectrum of viral strains.
Recent Advances in Electrochemical Chitosan-Based Chemosensors and Biosensors: Applications in Food Safety
Authors: Petrucci Rita , Pasquali Mauro , Scaramuzzo Francesca Anna , Curulli Antonella
Published: September 2021

Chitosan is a biopolymer derived from chitin. It is a non-toxic, biocompatible, bioactive, and biodegradable polymer. Due to its properties, chitosan has found applications in several and different fields such as agriculture, food industry, medicine, paper fabrication, textile industry, and water treatment. In addition to these properties, chitosan has a good film-forming ability which allows it to be widely used for the development of sensors and biosensors. This review is focused on the use of chitosan for the formulation of electrochemical chemosensors. It also aims to provide an overview of the advantages of using chitosan as an immobilization platform for biomolecules by highlighting its applications in electrochemical biosensors. Finally, applications of chitosan-based electrochemical chemosensors and biosensors in food safety are illustrated.
Topical Use of Cannabis sativa L. Biochemicals
Authors: Mnekin Léonid , Ripoll Lionel
Published: September 2021

Cannabis sativa L. plant is currently attracting increasing interest in cosmetics and dermatology. In this review, the biologically active compounds of hemp are discussed. Particularly the complex interactions of cannabinoids with the endocannabinoid system of the skin to treat various conditions (such as acne, allergic contact dermatitis, melanoma, and psoriasis) with clinical data. Moreover, the properties of some cannabinoids make them candidates as cosmetic actives for certain skin types. Hemp seed oil and its minor bioactive compounds such as terpenes, flavonoids, carotenoids, and phytosterols are also discussed for their added value in cosmetic formulation.
Synthesis and Characterization of Antibacterial Carbopol/ZnO Hybrid Nanoparticles Gel
Authors: Ismail Sameh H. , Hamdy Ahmed , Ismail Tamer Ahmed , Mahboub Heba H. , Mahmoud Walaa H. , Daoush Walid M.
Published: September 2021

This study recommends Carbopol/zinc oxide (ZnO) hybrid nanoparticles gel as an efficient antibacterial agent against different bacterial species. To this end, ZnO nanoparticles were synthesized using chemical precipitation derived from a zinc acetate solution with ammonium hydroxide as its precipitating agent under the effect of ultrasonic radiation. The synthesized ZnO nanoparticles were stabilized simultaneously in a freshly prepared Carbopol gel at a pH of 7. The chemical composition, phase identification, particle size and shape, surface charge, pore size distribution, and the BET surface area of the ZnO nanoparticles, as well as the Carbopol/ZnO hybrid Nanoparticles gel, were by XRD, SEM, TEM, AFM, DLS, Zeta potential and BET instruments. The results revealed that the synthesized ZnO nanoparticles were well-dispersed in the Carbopol gel network, and have a wurtzite-crystalline phase of spherical shape. Moreover, the Carbopol/ZnO hybrid nanoparticles gel exhibited a particle size distribution between ~9 and ~93 nm, and a surface area of 54.26 m2/g. The synthesized Carbopol/ZnO hybrid nanoparticles gel underwent an antibacterial sensitivity test against gram-negative K. pneumonia (ATCC 13883), Bacillus subtilis (ATCC 6633), and gram-positive Staphylococcus aureus (ATCC 6538) bacterial strains, and were compared with ampicillin as a reference antibiotic agent. The obtained results demonstrated that the synthesized Carbopol/ZnO hybrid nanoparticles gel exhibited a compatible bioactivity against the different strains of bacteria.
Virtual Care in Patients with Cancer: A Systematic Review
Authors: Singh Simron , Fletcher Glenn G. , Yao Xiaomei , Sussman Jonathan
Published: September 2021

Virtual care in cancer care existed in a limited fashion globally before the COVID-19 pandemic, mostly driven by geographic constraints. The pandemic has required dramatic shifts in health care delivery, including cancer care. We conducted a systematic review of comparative studies evaluating virtual versus in-person care in patients with cancer. Embase, APA PsycInfo, Ovid MEDLINE, and the Cochrane Library were searched for literature from January 2015 to 6 August 2020. We adhered to PRISMA guidelines and used the modified GRADE approach to evaluate the data. We included 34 full-text publications of 10 randomized controlled trials, 13 non-randomized comparative studies, and 5 ongoing randomized controlled trials. Evidence was divided into studies that provide psychosocial or genetic counselling and those that provide or assess medical and supportive care. The limited data in this review support that in the general field of psychological counselling, virtual or remote counselling can be equivalent to in-person counselling. In the area of genetic counselling, telephone counselling was more convenient and noninferior to usual care for all outcomes (knowledge, decision conflict, cancer distress, perceived stress, genetic counseling satisfaction). There are few data for clinical outcomes and supportive care. Future research should assess the role of virtual care in these areas. Protocol registration: PROSPERO CRD42020202871.
TEG® and ROTEM® Traces: Clinical Applications of Viscoelastic Coagulation Monitoring in Neonatal Intensive Care Unit
Authors: Cannata Giulia , Mariotti Zani Elena , Argentiero Alberto , Caminiti Caterina , Perrone Serafina , Esposito Susanna
Published: September 2021

The concentration of the majority of hemostatic proteins differs considerably in early life, especially in neonates compared to adulthood. Knowledge of the concept of developmental hemostasis is an essential prerequisite for the proper interpretation of conventional coagulation tests (CCT) and is critical to ensure the optimal diagnosis and treatment of hemorrhagic and thrombotic diseases in neonatal age. Viscoelastic tests (VETs) provide a point-of-care, real-time, global, and dynamic assessment of the mechanical properties of the coagulation system with the examination of both cellular and plasma protein contributions to the initiation, formation, and lysis of clots. In this work, we provide a narrative review of the basic principles of VETs and summarize current evidence regarding the two most studied point-of-care VETs, thromboelastography (TEG®) and rotational thromboelastometry (ROTEM®), in the field of neonatal care. A literature analysis shows that viscoelastic hemostatic monitoring appears to be a useful additive technique to CCT, allowing targeted therapy to be delivered quickly. These tools may allow researchers to determine the neonatal coagulation profile and detect neonatal patients at risk for postoperative bleeding, coagulation abnormalities in neonatal sepsis, and other bleeding events in a timely manner, guiding transfusion therapies using the goal-oriented transfusion algorithm. However, diagnosis and treatment algorithms incorporating VETs for neonatal patients in a variety of clinical situations should be developed and applied to improve clinical outcomes. Further studies should be performed to make routinary diagnostic and therapeutic application possible for the neonatal population.
Quantifying the Spatial Variability of Annual and Seasonal Changes in Riverscape Vegetation Using Drone Laser Scanning
Authors: Resop Jonathan P. , Lehmann Laura , Hession W. Cully
Published: September 2021

Riverscapes are complex ecosystems consisting of dynamic processes influenced by spatially heterogeneous physical features. A critical component of riverscapes is vegetation in the stream channel and floodplain, which influences flooding and provides habitat. Riverscape vegetation can be highly variable in size and structure, including wetland plants, grasses, shrubs, and trees. This vegetation variability is difficult to precisely measure over large extents with traditional surveying tools. Drone laser scanning (DLS), or UAV-based lidar, has shown potential for measuring topography and vegetation over large extents at a high resolution but has yet to be used to quantify both the temporal and spatial variability of riverscape vegetation. Scans were performed on a reach of Stroubles Creek in Blacksburg, VA, USA six times between 2017 and 2019. Change was calculated both annually and seasonally over the two-year period. Metrics were derived from the lidar scans to represent different aspects of riverscape vegetation: height, roughness, and density. Vegetation was classified as scrub or tree based on the height above ground and 604 trees were manually identified in the riverscape, which grew on average by 0.74 m annually. Trees had greater annual growth and scrub had greater seasonal variability. Height and roughness were better measures of annual growth and density was a better measure of seasonal variability. The results demonstrate the advantage of repeat surveys with high-resolution DLS for detecting seasonal variability in the riverscape environment, including the growth and decay of floodplain vegetation, which is critical information for various hydraulic and ecological applications.
Private Weakly-Random Sequences from Human Heart Rate for Quantum Amplification
Authors: Stankiewicz Maciej , Horodecki Karol , Sakarya Omer , Makowiec Danuta
Published: September 2021

We investigate whether the heart rate can be treated as a semi-random source with the aim of amplification by quantum devices. We use a semi-random source model called ε-Santha–Vazirani source, which can be amplified via quantum protocols to obtain a fully private random sequence. We analyze time intervals between consecutive heartbeats obtained from Holter electrocardiogram (ECG) recordings of people of different sex and age. We propose several transformations of the original time series into binary sequences. We have performed different statistical randomness tests and estimated quality parameters. We find that the heart can be treated as a good enough, and private by its nature, source of randomness that every human possesses. As such, in principle, it can be used as input to quantum device-independent randomness amplification protocols. The properly interpreted ε parameter can potentially serve as a new characteristic of the human heart from the perspective of medicine.
Adaptive Block-Based Compressed Video Sensing Based on Saliency Detection and Side Information
Authors: Wang Wei , Wang Jianming , Chen Jianhua
Published: September 2021

The setting of the measurement number for each block is very important for a block-based compressed sensing system. However, in practical applications, we only have the initial measurement results of the original signal on the sampling side instead of the original signal itself, therefore, we cannot directly allocate the appropriate measurement number for each block without the sparsity of the original signal. To solve this problem, we propose an adaptive block-based compressed video sensing scheme based on saliency detection and side information. According to the Johnson–Lindenstrauss lemma, we can use the initial measurement results to perform saliency detection and then obtain the saliency value for each block. Meanwhile, a side information frame which is an estimate of the current frame is generated on the reconstruction side by the proposed probability fusion model, and the significant coefficient proportion of each block is estimated through the side information frame. Both the saliency value and significant coefficient proportion can reflect the sparsity of the block. Finally, these two estimates of block sparsity are fused, so that we can simultaneously use intra-frame and inter-frame correlation for block sparsity estimation. Then the measurement number of each block can be allocated according to the fusion sparsity. Besides, we propose a global recovery model based on weighting, which can reduce the block effect of reconstructed frames. The experimental results show that, compared with existing schemes, the proposed scheme can achieve a significant improvement in peak signal-to-noise ratio (PSNR) at the same sampling rate.
Fostering Computational Thinking Skills: A Didactic Proposal for Elementary School Grades
Authors: Silva Ricardo , Fonseca Benjamim , Costa Cecília , Martins Fernando
Published: September 2021

There is a growing presence of technology in the daily lives of elementary school students, with a recent exponential rise due to the constraints of remote teaching during the COVID-19 pandemic. It is important to understand how the education system can contribute to helping students develop the required skills for technological careers, without neglecting its obligation to create conditions that allow them to acquire transversal skills and to enable them to exercise full citizenship. The integration of Educational Robotics and block programming activities in collaborative learning environments promotes the development of computational thinking and other ICT skills, as well as critical thinking, social skills, and problem solving. This paper presents a theoretical proposal of a didactic sequence for the introduction to educational robotics and programming with Scratch Jr. It is composed of three learning scenarios, designed for elementary school teaching. Its main goal is to create conditions that favour the development of computational thinking in a collaborative learning environment. With increasing complexity and degree of difficulty, all the tasks root from a common problem: How can we create an algorithm that programs the robot/sprite to reach a predetermined position?
Characterizing Team Orientations and Academic Performance in Cooperative Project-Based Learning Environments
Authors: Jaiswal Aparajita , Karabiyik Tugba , Thomas Paul , Magana Alejandra J.
Published: September 2021

Information technology professionals are required to possess both technical and professional skills while functioning in teams. Higher education institutions are promoting teamwork by engaging students in cooperative and project-based learning environments. We characterized teams based on their collective orientations and evaluated their team performance in a cooperative project-based learning environment situated in a sophomore-level systems analysis and design course. We explored the orientation patterns in terms of goals, roles, processes, and interpersonal relations (GRPI). Specifically, we analyzed team retrospectives of 23 teams using a mixed-method approach. Findings characterized teams into balanced and unbalanced orientations. Teams with balanced orientations demonstrated a higher level of team performance in terms of academic achievement than the unbalanced category.
Reasoning on Controversial Science Issues in Science Education and Science Communication
Authors: Beniermann Anna , Mecklenburg Laurens , Upmeier zu Belzen Annette
Published: September 2021

The ability to make evidence-based decisions, and hence to reason on questions concerning scientific and societal aspects, is a crucial goal in science education and science communication. However, science denial poses a constant challenge for society and education. Controversial science issues (CSI) encompass scientific knowledge rejected by the public as well as socioscientific issues, i.e., societal issues grounded in science that are frequently applied to science education. Generating evidence-based justifications for claims is central in scientific and informal reasoning. This study aims to describe attitudes and their justifications within the argumentations of a random online sample (N = 398) when reasoning informally on selected CSI. Following a deductive-inductive approach and qualitative content analysis of written open-ended answers, we identified five types of justifications based on a fine-grained category system. The results suggest a topic-specificity of justifications referring to specific scientific data, while justifications appealing to authorities tend to be common across topics. Subjective, and therefore normative, justifications were slightly related to conspiracy ideation and a general rejection of the scientific consensus. The category system could be applied to other CSI topics to help clarify the relation between scientific and informal reasoning in science education and communication.
School Refusal Behavior Profiles, Optimism/Pessimism, and Personality Traits in Spanish Children
Authors: Martín Miriam , Gonzálvez Carolina , Vicent María , Sanmartín Ricardo , Fernández-Sogorb Aitana , García-Fernández José M.
Published: September 2021

The relationship between school refusal behavior (SRB) profiles and personality traits has received little attention from investigators. Identifying the profiles of students with school attendance problems may improve the understanding of the characteristics defining these students. The aim of this study was to identify different SRB profiles and analyze the relationship between these profiles, and optimism/pessimism and personality traits. The School Refusal Assessment Scale-Revised, the Youth Life Orientation Test, and the Big Five Questionnaire were administrated to 739 Spanish students aged 8–11 (Mage = 9.92; SD = 1.12). Pearson’s correlation coefficients revealed a significant association between personality dimensions and SRB. Three distinct profiles were identified: (1) SRB by negative reinforcement (high scores on avoiding school-related stimuli provoking negative affectivity), (2) SRB by positive reinforcement (high scores on pursuing positive tangible reinforcement outside of school), and (3) Low SRB. The SRB profile by positive reinforcement scored higher on Extraversion, Agreeableness, Conscientiousness, Openness, and Optimism, whereas the SRB profile by negative reinforcement scored higher on Neuroticism and Pessimism. More statically significant differences were found between the negative and positive reinforcement profiles. The role of negative personality traits and pessimism as risk factors for students who are truant or refuse to attend school are discussed.
Effects of Chamber Pressures on the Passivation Layer of Hydrogenated Nano-Crystalline Silicon Mixed-Phase Thin Film by Using Microwave Annealing
Authors: Lin Jia-Hao , Wu Hung-Wei , Tien Wei-Chen , Hung Cheng-Yuan , Liu Shih-Kun
Published: September 2021

This paper proposes the effects of chamber pressures on the passivation layer of hydrogenated nano-crystalline silicon (nc-Si:H) mixed-phase thin film using microwave annealing (MWA) to achieve a high-quality thin film. The use of 40.68 MHz very-high-frequency plasma-enhanced chemical vapor deposition (VHFPECVD) deposited the nc-Si:H mixed-phase thin film on the top and bottom of the n-type crystalline silicon substrate. The chamber pressures (0.2, 0.4, 0.6, and 0.8 Torr) of the VHFPECVD were critical factors in controlling the carrier lifetime of the symmetric structure. By using the VHFPECVD to deposit the nc-Si:H and using the MWA to enhance the quality of the symmetric structure, the deposited nc-Si:H’s properties of a crystalline volume fraction of 29.6%, an optical bandgap of 1.744 eV, and a carrier lifetime of 2942.36 μs were well achieved, and could be valuable in thin-film solar-cell applications.
The Assessment of Energy Efficiency versus Planning of Rail Freight Traffic: A Case Study on the Example of Poland
Authors: Gołębiowski Piotr , Jacyna Marianna , Stańczak Andrzej
Published: September 2021

The issues addressed by the article concern the assessment of energy efficiency in rail transport, resulting from the proper organization of rail traffic. The problems related to energy consumption and, thus, the negative impact of rail transport on the natural environment are highly significant in terms of the green deal concept, climate change and sustainable development. In this article, energy efficiency is investigated in the context of minimizing the energy consumption necessary to satisfy a specific transport requirement. The essence of this article is to present an approach to energy-efficient planning of rail freight traffic. This article aims to develop a method covers the allocation of railway vehicles dedicated to freight traffic (locomotives and railcars) to perform a defined transport task, taking into account the energy efficiency assessment of the solution, routing the train launched with regard to the accomplishment of the defined transport task on the railway network, and determining the conditions of transport for a defined transport task, taking into account the allocated rolling stock (locomotives and railcars) and the route. In this article, based on the presented state of knowledge, a decision-making model has been proposed, including the model’s parameters, the values being searched for, indicators for assessing the quality of the solution, as well as the limitations and boundary conditions of the problem. The function of minimizing the energy consumption necessary to transport a shipment within the railway network (determining the energy efficiency of the proposed solution) has been proposed as the criterion. In addition, a description of the proprietary method of selecting rolling stock for accomplishing tasks, based on the assessment of the energy efficiency of the solution and a case study illustrating the operation of the method on the example of the area of Poland, has been presented.
Optimization Algorithms: Optimal Parameters Computation for Modeling the Polarization Curves of a PEFC Considering the Effect of the Relative Humidity
Authors: Encalada-Dávila Ángel , Echeverría Samir , Santana-Villamar Jordy , Cedeño Gabriel , Espinoza-Andaluz Mayken
Published: September 2021

The development of green energy conversion devices has been promising to face climate change and global warming challenges over the last few years. Energy applications require a confident performance prediction, especially in polymer electrolyte fuel cell (PEFC), to guarantee optimal operation. Several researchers have employed optimization algorithms (OAs) to identify operating parameters to improve the PEFC performance. In the current study, several nature-based OAs have been performed to compute the optimal parameters used to describe the polarization curves in a PEFC. Different relative humidity (RH) values, one of the most influential variables on PEFC performance, have been considered. To develop this study, experimental data have been collected from a lab-scale fuel cell test system establishing different RH percentages, from 18 to 100%. OAs like neural network algorithm (NNA), improved grey-wolf optimizer (I-GWO), ant lion optimizer (ALO), bird swarm algorithm (BSA), and multi-verse optimization (MVO) were evaluated and compared using statistical parameters as training error and time. Results gave enough information to conclude that NNA had better performance and showed better results over other highlighted OAs. Finally, it was found that sparsity and noise are more present at lower relative humidity values. At low RH, a PEFC operates under critical conditions, affecting the fitting on OAs.
Modeling of Dielectric Electroactive Polymer Actuators with Elliptical Shapes
Authors: Bernat Jakub , Kołota Jakub
Published: September 2021

Dielectric electroactive polymers have been widely used in recent applications based on smart materials. The many advantages of dielectric membranes, such as softness and responsiveness to electric stimuli, have lead to their application in actuators. Recently, researchers have aimed to improve the design of dielectric electroactive polymer actuators. The modifications of DEAP actuators are designed to change the bias mechanism, such as spring, pneumatic, and additional mass, or to provide a double cone configuration. In this work, the modification of the shape of the actuator was analyzed. In the standard approach, a circular shape is often used, while this research uses an elliptical shape for the actuator. In this study, it was shown that this construction allows a wider range of movement. The paper describes a new design of the device and its model. Further, the device is verified by the measurements.
At what Pressure Shall CO2 Be Transported by Ship? An in-Depth Cost Comparison of 7 and 15 Barg Shipping
Authors: Roussanaly Simon , Deng Han , Skaugen Geir , Gundersen Truls
Published: September 2021

The pipeline has historically been the preferred means to transport CO2 due to its low cost for short distances and opportunities for economies of scale. However, interest in vessel-based transport of CO2 is growing. While most of the literature has assumed that CO2 shipping would take place at low pressure (at 7 barg and −46 °C), the issue of identifying best transport conditions, in terms of pressure, temperature, and gas composition, is becoming more relevant as ship-based carbon capture and storage chains move towards implementation. This study focuses on an in-depth comparison of the two primary and relevant transport pressures, 7 and 15 barg, for annual volumes up to 20 MtCO2/year and transport distances up to 2000 km. We also address the impact of a number of key factors on optimal transport conditions, including (a) transport between harbours versus transport to an offshore site, (b) CO2 pressure prior to conditioning, (c) the presence of impurities and of purity constraints, and (d) maximum feasible ship capacities for the 7 and 15 barg options. Overall, we have found that 7 barg shipping is the most cost-efficient option for the combinations of distance and annual volume where transport by ship is the cost-optimal means of transport. Furthermore, 7 barg shipping can enable significant cost reductions (beyond 30%) compared to 15 barg shipping for a wide range of annual volume capacities.
Effect of Individual Volt/var Control Strategies in LINK-Based Smart Grids with a High Photovoltaic Share
Authors: Schultis Daniel-Leon , Ilo Albana
Published: September 2021

The increasing share of distributed energy resources aggravates voltage limit compliance within the electric power system. Nowadays, various inverter-based Volt/var control strategies, such as cosφ(P) and Q(U), for low voltage feeder connected L(U) local control and on-load tap changers in distribution substations are investigated to mitigate the voltage limit violations caused by the extensive integration of rooftop photovoltaics. This study extends the L(U) control strategy to X(U) to also cover the case of a significant load increase, e.g., related to e-mobility. Control ensembles, including the reactive power autarky of customer plants, are also considered. All Volt/var control strategies are compared by conducting load flow calculations in a test distribution grid. For the first time, they are embedded into the LINK-based Volt/var chain scheme to provide a holistic view of their behavior and to facilitate systematic analysis. Their effect is assessed by calculating the voltage limit distortion and reactive power flows at different Link-Grid boundaries, the corresponding active power losses, and the distribution transformer loadings. The results show that the control ensemble X(U) local control combined with reactive power self-sufficient customer plants performs better than the cosφ(P) and Q(U) local control strategies and the on-load tap changers in distribution substations.
Detecting Pipeline Pathways in Landsat 5 Satellite Images with Deep Learning
Authors: Dasenbrock Jan , Pluta Adam , Zech Matthias , Medjroubi Wided
Published: September 2021

Energy system modeling is essential in analyzing present and future system configurations motivated by the energy transition. Energy models need various input data sets at different scales, including detailed information about energy generation and transport infrastructure. However, accessing such data sets is not straightforward and often restricted, especially for energy infrastructure data. We present a detection model for the automatic recognition of pipeline pathways using a Convolutional Neural Network (CNN) to address this lack of energy infrastructure data sets. The model was trained with historical low-resolution satellite images of the construction phase of British gas transport pipelines, made with the Landsat 5 Thematic Mapper instrument. The satellite images have been automatically labeled with the help of high-resolution pipeline route data provided by the respective Transmission System Operator (TSO). We have used data augmentation on the training data and trained our model with four different initial learning rates. The models trained with the different learning rates have been validated with 5-fold cross-validation using the Intersection over Union (IoU) metric. We show that our model can reliably identify pipeline pathways despite the comparably low resolution of the used satellite images. Further, we have successfully tested the model’s capability in other geographic regions by deploying satellite images of the NEL pipeline in Northern Germany.
Review of Zero Energy Building Concept-Definition and Developments in Latin America: A Framework Definition for Application in Panama
Authors: Chen Austin Miguel , Chung-Camargo Katherine , Mora Dafni
Published: September 2021

In recent decades, European countries have developed concepts, definitions, and construction technologies for Zero Energy Building (ZEB) that are effective and correspond to their specific climates. Latin American countries are still trying to find adequate solutions which respond to the local climatic, cultural, social, technical, and economic context. As such, this paper aims to establish the basis of the minimum energy efficiency and the renewable threshold for the definition of ZEB in order to better understand the application in Panama, based on assessing the energy regulations implemented in Panama. To achieve this aim, a review concentrated on the concept-definition and implementation adopted by Latin American countries is presented first before the paper converges into defining a framework for application in Panama. Finally, a case-study-based theoretical framework proposing a ZEB definition for Panama is discussed. The results of this study showed a net primary energy balance, of which the range falls into a plus energy building definition, indicating that all of the cases studied could supply their electricity needs using Photovoltaic generation. All dwellings studied have the potential to become a plus energy building, depending on the available roof surface area. Finally, a strengths, weaknesses, opportunities and threats analysis is presented in order to assess and support the introduction of such a ZEB definition and framework.
Assessing the Energy, Indoor Air Quality, and Moisture Performance for a Three-Story Building Using an Integrated Model, Part Three: Development of Integrated Model and Applications
Authors: Heibati Seyedmohammadreza , Maref Wahid , Saber Hamed H.
Published: September 2021

The overall building performance depends mainly on the energy performance, indoor air quality, and moisture performance. In order to accurately calculate the building performance, the development of a model with the ability to integrate all three performances is required. In this research, a combination of three models namely EnergyPlus for energy, CONTAM for indoor air quality, and WUFI for moisture transport are used to develop an integrated model. The mechanism of this combination is based on the exchange of temperatures, airflows, and heating-cooling flows control variables between all three sub-models. By using the paired sample t-test, an integrated model is verified and its accuracy is validated. The accuracy of the integrated model is verified by the paired sample t-test. In order to analyze the accuracy of the integrated model in comparison with single models, four scenarios of airtight fan off, airtight fan on, leaky fan off, and leaky fan on are defined for a three-story-house subjected to three different climate cities of Montreal, Vancouver, and Miami. Percentage differences of simulated measures with the ASHRAE Standard are considered as the performance criteria. The simulated results by single and integrated models are compared and analyzed. Finally, the scenarios with the high performances are evaluated in terms of energy efficiency, indoor air quality, and moisture for Montreal, Vancouver, and Miami. Overall, it can be concluded that an integrated model should be developed.
Influence of Operation Schemes on the Performance of the Natural Draft Hybrid Cooling System for Thermal Power Generation
Authors: Wei Huimin , Chen Lin , Ge Zhihua , Yang Lijun , Du Xiaoze
Published: September 2021

For thermal power generation, the natural draft hybrid cooling system (NDHCs) with airflows in parallel design gives a multi-objective solution for water saving, performance enhancement and maintenance issues, like corrosion, by switching the loads of wet and dry sections. Performances of dry and wet sections interact with each other in the highly integrated system, increasing the complexity of operation strategies. In this context the present paper examines eight different operation schemes to reveal the relationships of ambient conditions and operation schemes. Comprehensive comparisons in the view of cooling efficiency with a same water inlet temperature are conducted firstly. Results show that there exists energy-saving potentials of the water evaporated rate, cooling performances and the pump power for different schemes. Based on the practical boundary conditions, including those of weather data, operation hours and market factors, optimal operation strategies of hybrid cooling are designed to minimize the operation costs of the energy system. For the 660 MW power generating unit integrated with a natural draft dry cooling system (NDDCs), operation costs based on NDHC after optimization decreased about 0.8% in 2010 and 0.35% in 2018 compared with that of the basic system. When comparing with the designed operation modes of hybrid cooling, 0.07 million dollars is saved after optimization.
From Clothing Rations to Fast Fashion: Utilising Regenerated Protein Fibres to Alleviate Pressures on Mass Production
Authors: Stenton Marie , Kapsali Veronika , Blackburn Richard S. , Houghton Joseph A.
Published: September 2021

Sustainable methods of practice within the fashion and textile industry (FTI) often strive to employ a circular economy that aims to eliminate waste through the continual use of resources. Complex problems such as waste, consumption, and overproduction are heavily intertwined; the main aim of this paper is to report on research focused on re-examining the potential of food waste streams as a commercially viable and circular source of raw materials for the FTI. Herein, regenerated protein fibres (RPFs) from food production waste streams rich in protein have been chosen as the main topic of focus. RPFs have a rich and relevant history from a local manufacturing perspective during wartime and post-war clothing rationing (1941–1949) in the UK. RPFs were used to meet civilian needs for wool-based textiles as part of a wider series of ‘make do and mend’ strategies designed to manage the consumption of new textile products. However, RPFs demonstrated inferior quality in terms of durability when compared to wool-based textiles, a significant contributing factor to the consequent commercial phasing out of RPFs. In today’s take–make–waste model, the FTI landscape can be defined by speed, from slow (high-quality materials and construction, long-lasting products) to fast (seasonal, disposable, low-quality materials and construction), the latter infamous for dire environmental impacts. A key objective of this research is to review the association of quality and longevity within the context of a local and circular fashion economy in which textile quality and lifecycle analysis are holistically matched to the longevity of the textile, garment, or product to reduce waste across the supply chain.