bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Assessment of Neuroinflammatory Markers and Antioxidants in Neonates with Hyperbilirubinemia and Their Association with Acute Bilirubin Encephalopathy
Authors: Midan Dina Abdel Razek , Bahbah Wael A. , Bayomy Noha Rabie , Ashour Noha M.
Published: April 2022

Objective: To assess the oxidant and antioxidant status in neonates with and without hyperbilirubinemia and their association with early manifestations of acute bilirubin encephalopathy (ABE), in addition to eliciting the possible oxidative effects of phototherapy. Methods: This prospective observational study was conducted with 104 full-term newborns at Menoufia University Hospitals from January 2020 to January 2021 to help resolve the debate regarding whether bilirubin is an antioxidant. The cases group (Group I) included 52 full-term newborns (37–40 weeks) with hyperbilirubinemia during the neonatal period, while the control group (Group II) included 52 healthy, full-term age and sex-matched newborns who did not have hyperbilirubinemia. The cases group was further subdivided into Group Ia (n = 12), which included newborns who presented with neurological manifestations suggesting early ABE, and Group Ib (n = 40), which included newborns with no signs suggestive of ABE. All newborns were subjected to clinical and neurological examinations, as well as laboratory investigations. Results: Comparing the specific biological markers between the Group 1 subgroups before phototherapy, the mean plasma levels of prostaglandin-Em, prostaglandin E2, and TSB were significantly higher in Subgroup I(a) (all p < 0.05). After phototherapy, Subgroup I(a) patients had significantly higher levels of prostaglandin-Em, DSB, and TSB (p < 0.05). The biological marker levels improved after phototherapy in terms of TAC (0.811 vs. 0.903), MDA (8.18 vs. 5.13), prostaglandin-Em (37.47 vs. 27.23), prostaglandin E2 (81.09 vs. 31.49), DSB (1.21 vs. 0.55), and TSB (16.63 vs. 8.26; p-value < 0.05). Conclusion: Our study showed that an elevated level of serum bilirubin increases oxidative stress and decreases antioxidant capacity. The reduction in bilirubin levels by phototherapy is associated with a decrease in oxidative stress markers (MDA, PGEm, and PGE2) and an upsurge in TAC, highlighting the absence of oxidative stress effects arising from phototherapy. Neonates with neurological manifestations suggesting ABE had higher levels of oxidative stress markers and lower levels of total antioxidant capacity than those without.
An Updated Overview of MRI Injuries in Neonatal Encephalopathy: LyTONEPAL Cohort
Authors: Beck Jonathan , Loron Gauthier , Ancel Pierre-Yves , Alison Marianne , Hertz Pannier Lucie , Vo Van Philippe , Debillon Thierry , Bednarek Nathalie
Published: April 2022

Background: Brain magnetic resonance imaging (MRI) is a key tool for the prognostication of encephalic newborns in the context of hypoxic−ischemic events. The purpose of this study was to finely characterize brain injuries in this context. Methods: We provided a complete, descriptive analysis of the brain MRIs of infants included in the French national, multicentric cohort LyTONEPAL. Results: Among 794 eligible infants, 520 (65.5%) with MRI before 12 days of life, grade II or III encephalopathy and gestational age ≥36 weeks were included. Half of the population had a brain injury (52.4%); MRIs were acquired before 6 days of life among 247 (47.5%) newborns. The basal ganglia (BGT), white matter (WM) and cortex were the three predominant sites of injuries, affecting 33.8% (n = 171), 33.5% (n = 166) and 25.6% (n = 128) of participants, respectively. The thalamus and the periventricular WM were the predominant sublocations. The BGT, posterior limb internal capsule, brainstem and cortical injuries appeared more frequently in the early MRI group than in the late MRI group. Conclusion: This study described an overview of brain injuries in hypoxic−ischemic neonatal encephalopathy. The basal ganglia with the thalamus and the WM with periventricular sublocation injuries were predominant. Comprehensive identification of brain injuries in the context of HIE may provide insight into the mechanism and time of occurrence.
Insights on the Corrosion Resistance of Reinforced Recycled Aggregate Concrete
Authors: Villagrán-Zaccardi Yury A. , Pico-Cortés Carlos M. , Etcheverry Juan M. , Santillán Lautaro R. , Sosa María E.
Published: April 2022

Recycled aggregate produced from crushed waste concrete is suitable for use in structural concrete. It reduces the demand for non-renewable resources and also for energy in general. However, RA is more porous than most natural aggregates. The porosity of the concrete cover defines the corrosion resistance of reinforced concrete, and it is therefore disputed how the use of recycled aggregate may affect the durability of reinforced concrete. This paper describes the corrosion-related performance of reinforced concrete with recycled aggregates in the initiation stage (determined by the carbonation and chloride ingress) and propagation stage (determined by the electrical resistivity and cracking) of corrosion. The aspects of interest are not only the porosity of RA but also its effects on the chloride binding, carbonation, electrochemical properties and corrosion cracking development.
Design, Simulation and Performance Research of New Biomaterial Mg30Zn30Sn30Sr5Bi5
Authors: Ma Beiyi , Ju Dongying , Liu Qian
Published: April 2022

This study focused on the design and the preparation method of a new biomaterial, Mg30Zn30Sn30Sr5Bi5 (at%) alloy, and its simulation and property analyses. Based on the comprehensive consideration of the preparation of high-entropy alloys, the selection of biomaterial elements, and the existing research results of common Mg-based materials, the atomic percentage of various elements, that is, Mg:Zn:Sn:Sr:Bi = 30:30:30:5:5, was determined. Using the theoretical methods of thermodynamic performance analysis and solidification performance analysis, the proposed composition was simulated and analyzed. The analysis results showed that the mechanical properties of the new material can meet the design requirements, and it can be prepared in physical form. XRD, SEM, PSD, compression tests, and other experimental tests were conducted on the material, and the alloy composition and distribution law showed various characteristics, which conformed to the “chaotic” characteristics of high-entropy alloys. The elastic modulus of the material was 17.98 GPa, which is within the 0–20 GPa elastic modulus range of human bone. This means that it can avoid the occurrence of stress shielding problems more effectively during the material implantation process.
Qipengyuania pacifica sp. nov., a Novel Carotenoid-Producing Marine Bacterium of the Family Erythrobacteraceae, Isolated from Sponge (Demospongiae), and Antimicrobial Potential of Its Crude Extract
Authors: Tareen Sanaullah , Risdian Chandra , Müsken Mathias , Wink Joachim
Published: April 2022

A marine Alphaproteobacterium designated as strain NZ-96T was isolated in February 2021, from a sponge species (Demospongiae) collected in muddy sediments with boulders and old chimneys in Otago/Canterbury Slope, Pacific Ocean, New Zealand. The isolate was found to be Gram-negative, rod-shaped, aerobic, motile, and produced yellow-colored colonies. The isolate was positive for alkaline phosphatase, leucine arylamidase, trypsin, catalase, and oxidase and negative for α-galactosidase and urease. It was resistant to many antibiotics including hygromycin, trimethoprim, spectinomycin, ampicillin, oxytetracycline, cephalosporin, bacitracin, and polymyxin. The 16S rRNA gene-based phylogenetic analyses exhibited that strain NZ-96T belonged to the genus Qipengyuania and showed 98.3–98.8% 16S rRNA gene sequence similarity to its closest relatives. The major respiratory quinone was ubiquinone-10 (Q-10). The polar lipid profile consisted of phosphatidylcholine, sphingoglycolipid, phosphatidylglycerol, one unknown polar lipid, and three unknown glycolipids. The major fatty acids were C18:1ω12t, C16:0, C16:1ω7c, C17:1ω6c, C16:02-OH, and C14:0 2-OH. Carotenoid were produced. The crude extract showed pronounced activity against Staphylococcus aureus Newman and Bacillus subtilis DSM 10. Pairwise ANI and dDDH values of strain NZ-96T and closely related phylogenetic hits were below the threshold values of 95% and 70%, respectively. Genes for trehalose biosynthesis, aspartate-semialdehyde dehydrogenase, flagellar biosynthesis, fatty acid biosynthesis, and antibiotics resistance were present, which aids in isolate survival in a sea or ocean environment. The DNA G+C content was 60.8% (by genome). Based on data obtained by the polyphasic approach, strain NZ-96T (= DSM 112811T = NCCB 100842T) represents a novel species of the genus Qipengyuania, for which the name Qipengyuania pacifica sp. nov. is proposed.
HAGDAVS: Height-Augmented Geo-Located Dataset for Detection and Semantic Segmentation of Vehicles in Drone Aerial Orthomosaics
Authors: Ballesteros John R. , Sanchez-Torres German , Branch-Bedoya John W.
Published: April 2022

Detection and Semantic Segmentation of vehicles in drone aerial orthomosaics has applications in a variety of fields such as security, traffic and parking management, urban planning, logistics, and transportation, among many others. This paper presents the HAGDAVS dataset fusing RGB spectral channel and Digital Surface Model DSM for the detection and segmentation of vehicles from aerial drone images, including three vehicle classes: cars, motorcycles, and ghosts (motorcycle or car). We supply DSM as an additional variable to be included in deep learning and computer vision models to increase its accuracy. RGB orthomosaic, RG-DSM fusion, and multi-label mask are provided in Tag Image File Format. Geo-located vehicle bounding boxes are provided in GeoJSON vector format. We also describes the acquisition of drone data, the derived products, and the workflow to produce the dataset. Researchers would benefit from using the proposed dataset to improve results in the case of vehicle occlusion, geo-location, and the need for cleaning ghost vehicles. As far as we know, this is the first openly available dataset for vehicle detection and segmentation, comprising RG-DSM drone data fusion and different color masks for motorcycles, cars, and ghosts.
Pathological Evaluation of Rectal Cancer Specimens Using Micro-Computed Tomography
Authors: Yoshida Masao , Cesmecioglu Emine , Firat Canan , Sakamoto Hirotsugu , Teplov Alexei , Kawata Noboru , Ntiamoah Peter , Ohnishi Takashi , Ibrahim Kareem , Vakiani Efsevia , Garcia-Aguilar Julio , Hameed Meera , Shia Jinru , Yagi Yukako
Published: April 2022

Whole-block imaging (WBI) using micro-computed tomography (micro-CT) allows the nondestructive reconstruction of a three-dimensional view of tissues, implying that WBI may be used for accurate pathological evaluation of patients with rectal cancer. HOWEVER, the clinical impact of this approach is unclear. We aimed to clarify the efficacy of WBI in the whole-mount specimens of locally advanced rectal cancer. A total of 237 whole-mount formalin-fixed paraffin-embedded blocks from 13 patients with rectal cancer who underwent surgical treatment were enrolled and scanned with micro-CT to generate three-dimensional images. WBI was evaluated following the conventional pathological review of the corresponding whole-slide imaging (WSI). WBI identified all tumor sites detected using WSI. Furthermore, WBI revealed one additional tumor site, which was not detected using WSI. Tumor resection margin was significantly closer to the soft-tissue edge when measured using WBI (7.7 mm vs. 6.6 mm, p < 0.01). Seventy-six percent of tumor deposits on WSI were changed according to the evidence of tumor interaction with the surrounding tissues confirmed using WBI. Furthermore, WBI revealed 25 additional lymph nodes, six of which were metastatic. The combination of conventional hematoxylin and eosin-stained imaging and WBI may contribute to an accurate pathological assessment.
Detection of Incomplete Irreversible Electroporation (IRE) and Microwave Ablation (MWA) of Hepatocellular Carcinoma (HCC) Using Iodine Quantification in Dual Energy Computed Tomography (DECT)
Authors: Bäumler Wolf , Beyer Lukas Philipp , Lürken Lukas , Wiggermann Philipp , Stroszczynski Christian , Dollinger Marco , Schicho Andreas
Published: April 2022

Early detection of local tumor progression (LTP) after irreversible electroporation (IRE) and microwave ablation (MWA) of hepatocellular carcinoma (HCC) remains challenging. The goal of this study was to identify cases with insufficient ablation and prevent HCC recurrencies by measuring iodine uptake using dual-energy computed tomography (DECT). In 54 HCC-patients, the volumetric iodine concentration (VIC) of the central and peripheral ablation area was evaluated by DECT within 24 h after IRE or MWA. Follow-up was performed with CT and/or MRI at 6 weeks, 3, 6, 9, and 12 months, respectively. In both groups, LTP was solely detected in the peripheral area (IRE: n = 4; MWA: n = 4) and LTP patients showed significantly higher VIC values in the peripheral zone than patients without LTP (IRE: * p = 0.0005; MWA: * p = 0.000). In IRE-LTP patients, no significant difference between the VIC values of non-ablated liver tissue and the peripheral zone was detected (p = 0.155). The peripheral zones of IRE patients without LTP (* p = 0.000) and MWA patients, irrespective of the presence of LTP (LTP: * p = 0.005; without LTP: * p = 0.000), showed significantly lower VIC values than non-ablated liver parenchyma. Higher BCLC tumor stages were indicative for LTP (* p = 0.008). The study suggests that elevated iodine uptake in the peripheral ablation zone could help identify LTP after IRE and MWA of HCC.
Surgery in Advanced Ovary Cancer: Primary versus Interval Cytoreduction
Authors: Cummings Mackenzie , Nicolais Olivia , Shahin Mark
Published: April 2022

Primary debulking surgery (PDS) has remained the only treatment of ovarian cancer with survival advantage since its development in the 1970s. However, survival advantage is only observed in patients who are optimally resected. Neoadjuvant chemotherapy (NACT) has emerged as an alternative for patients in whom optimal resection is unlikely and/or patients with comorbidities at high risk for perioperative complications. The purpose of this review is to summarize the evidence to date for PDS and NACT in the treatment of stage III/IV ovarian carcinoma. We systematically searched the PubMed database for relevant articles. Prior to 2010, NACT was reserved for non-surgical candidates. After publication of EORTC 55971, the first randomized trial demonstrating non-inferiority of NACT followed by interval debulking surgery, NACT was considered in a wider breadth of patients. Since EORTC 55971, 3 randomized trials—CHORUS, JCOG0602, and SCORPION—have studied NACT versus PDS. While CHORUS supported EORTC 55971, JCOG0602 failed to demonstrate non-inferiority and SCORPION failed to demonstrate superiority of NACT. Despite conflicting data, a subset of patients would benefit from NACT while preserving survival including poor surgical candidates and inoperable disease. Further randomized trials are needed to assess the role of NACT.
Sodium-Glucose Cotransporter-2 Inhibitors Improve Heart Failure with Reduced Ejection Fraction Outcomes by Reducing Edema and Congestion
Authors: Hernandez Michelle , Sullivan Ryan D. , McCune Mariana E. , Reed Guy L. , Gladysheva Inna P.
Published: April 2022

Pathological sodium-water retention or edema/congestion is a primary cause of heart failure (HF) decompensation, clinical symptoms, hospitalization, reduced quality of life, and premature mortality. Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) based therapies reduce hospitalization due to HF, improve functional status, quality, and duration of life in patients with HF with reduced ejection fraction (HFrEF) independently of their glycemic status. The pathophysiologic mechanisms and molecular pathways responsible for the benefits of SGLT-2i in HFrEF remain inconclusive, but SGLT-2i may help HFrEF by normalizing salt-water homeostasis to prevent clinical edema/congestion. In HFrEF, edema and congestion are related to compromised cardiac function. Edema and congestion are further aggravated by renal and pulmonary abnormalities. Treatment of HFrEF patients with SGLT-2i enhances natriuresis/diuresis, improves cardiac function, and reduces natriuretic peptide plasma levels. In this review, we summarize current clinical research studies related to outcomes of SGLT-2i treatment in HFrEF with a specific focus on their contribution to relieving or preventing edema and congestion, slowing HF progression, and decreasing the rate of rehospitalization and cardiovascular mortality.
Artificial Intelligence (Enhanced Super-Resolution Generative Adversarial Network) for Calcium Deblooming in Coronary Computed Tomography Angiography: A Feasibility Study
Authors: Sun Zhonghua , Ng Curtise K. C.
Published: April 2022

Background: The presence of heavy calcification in the coronary artery always presents a challenge for coronary computed tomography angiography (CCTA) in assessing the degree of coronary stenosis due to blooming artifacts associated with calcified plaques. Our study purpose was to use an advanced artificial intelligence (enhanced super-resolution generative adversarial network [ESRGAN]) model to suppress the blooming artifact in CCTA and determine its effect on improving the diagnostic performance of CCTA in calcified plaques. Methods: A total of 184 calcified plaques from 50 patients who underwent both CCTA and invasive coronary angiography (ICA) were analysed with measurements of coronary lumen on the original CCTA, and three sets of ESRGAN-processed images including ESRGAN-high-resolution (ESRGAN-HR), ESRGAN-average and ESRGAN-median with ICA as the reference method for determining sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results: ESRGAN-processed images improved the specificity and PPV at all three coronary arteries (LAD-left anterior descending, LCx-left circumflex and RCA-right coronary artery) compared to original CCTA with ESRGAN-median resulting in the highest values being 41.0% (95% confidence interval [CI]: 30%, 52.7%) and 26.9% (95% CI: 22.9%, 31.4%) at LAD; 41.7% (95% CI: 22.1%, 63.4%) and 36.4% (95% CI: 28.9%, 44.5%) at LCx; 55% (95% CI: 38.5%, 70.7%) and 47.1% (95% CI: 38.7%, 55.6%) at RCA; while corresponding values for original CCTA were 21.8% (95% CI: 13.2%, 32.6%) and 22.8% (95% CI: 20.8%, 24.9%); 12.5% (95% CI: 2.6%, 32.4%) and 27.6% (95% CI: 24.7%, 30.7%); 17.5% (95% CI: 7.3%, 32.8%) and 32.7% (95% CI: 29.6%, 35.9%) at LAD, LCx and RCA, respectively. There was no significant effect on sensitivity and NPV between the original CCTA and ESRGAN-processed images at all three coronary arteries. The area under the receiver operating characteristic curve was the highest with ESRGAN-median images at the RCA level with values being 0.76 (95% CI: 0.64, 0.89), 0.81 (95% CI: 0.69, 0.93), 0.82 (95% CI: 0.71, 0.94) and 0.86 (95% CI: 0.76, 0.96) corresponding to original CCTA and ESRGAN-HR, average and median images, respectively. Conclusions: This feasibility study shows the potential value of ESRGAN-processed images in improving the diagnostic value of CCTA for patients with calcified plaques.
Digital Mounting Jigs: A Novel Technique
Authors: Akl Mohammed A. , Mansour Dina E. , Zheng Fengyuan , Seong WookJin
Published: April 2022

The accuracy with which virtual articulators are able to simulate centric and eccentric movements when fabricating definitive restorations has not yet been proven to be on par with mechanical articulators which have been reliably used in restorative dentistry for decades. This may be an issue when working on complex restorative cases utilizing a digital workflow and could result in considerable chairside adjustment time and subsequent loss of occlusal anatomy and morphology. Interchanging between digital and analog workflows is a challenge as accurate cross-mounting is difficult due to the changes that occur as the digital and analog workflows progress. This technique article provides a method for the fabrication of simple digital mounting jigs that enable clinicians and laboratory technicians to mount printed digital wax-ups and working casts back onto a programmed mechanical articulator, opposing diagnostic casts that have originally been mounted by means of a facebow transfer. This allows for the positioning of printed digital wax-ups and working casts to be in the correct 3-dimensional spatial relationship on the mechanical articulator for any necessary occlusal adjustments of the digitally designed wax-ups and/or definitive restorations before they are moved chairside.
Computation of High-Frequency Sub-National Spatial Consumer Price Indexes Using Web Scraping Techniques
Authors: Benedetti Ilaria , Laureti Tiziana , Palumbo Luigi , Rose Brandon M.
Published: April 2022

The development of Information and Communications Technology and digital economies has contributed to changes in the consumption of goods and services in various areas of life, affecting the growing expectations of users in relation to price statistics. Therefore, it is important to provide information on differences in consumer prices across space and over time in a timely manner. Web-scraped data, which is the process of collecting large amounts of data from the web, offer the potential to improve greatly the quality and efficiency of consumer price indices. In this paper, we explore the use of web-scraped data for compiling high-frequency price indexes for groups of products by using the time-interaction-region product model. We computed monthly average prices for five entry-level items according to the Consumer Price Index for All Urban Consumers (CPI-U) classification and tracked their evolution over time in 11 USA cities reported in our dataset. Even if our dataset covers a small percentage of the CPI-U index, results show how web scraping data may provide timely estimates of sub-national SPI evolution and unveil seasonal trends for specific categories.
Design and Performance Tests of a Fault Current-Limiting-Type Tri-Axial HTS Cable Prototype
Authors: Xia Yajun , Song Yuntao , Ma Tao , Zheng Jinxing , Liu Huajun , Liu Fang , Song Meng
Published: April 2022

Current-limiting superconducting cable uses the quench resistance of superconductor under short-circuit current to improve the short-circuit impedance of the system. In this paper, the design of current-limiting 10 kV three-phase tri-axial superconducting cable is studied. The design methods of cable conductor layer, insulation layer and current-limiting characteristics are given, and one 5 m-long sample is fabricated for testing. The sample is made of stainless-steel-reinforced yttrium barium copper oxide (YBCO) tape, with an expected rated current of 2.5 kA and rated voltage of 10 kV. The test results show that the designed cable can transmit a maximum AC current of 3.0 kA at 77 K. The cable has passed the power frequency withstand voltage, partial discharge and lightning impulse tests. The current limiting characteristics under the action of DC pulse current show that the cable can quickly quench and produce resistance, and the corresponding equivalent resistance value also changes along with current amplitude and duration.
Preliminary Design of a Receding Horizon Controller Supported by Adaptive Feedback
Authors: Issa Hazem , Tar József K.
Published: April 2022

Receding horizon controllers are special approximations of optimal controllers in which the continuous time variable is discretized over a horizon of optimization. The cost function is defined as the sum of contributions calculated in the grid points and it is minimized under the constraint that expresses the dynamic model of the controlled system. The control force calculated only for one step of the horizon is exerted, and the next horizon is redesigned from the measured initial state to avoid the accumulation of the effects of modeling errors. In the suggested solution, the dynamic model is directly used without any gradient reduction by using a transition between the gradient descent and the Newton–Raphson methods to achieve possibly fast operation. The optimization is carried out for an "overestimated" dynamic model, and instead of using the optimized force components the optimized trajectory is adaptively tracked by an available approximate dynamic model of the controlled system. For speeding up the operation of the system, various cost functions have been considered in the past. The operation of the method is exemplified by simulations made for new cost functions and the dynamic control of a 4-degrees-of-freedom SCARA robot using the simple sequential Julia language code realizing Euler integration.
Optimal Coordinated Control Strategy of Clustered DC Microgrids under Load-Generation Uncertainties Based on GWO
Authors: Al-Tameemi Zaid Hamid Abdulabbas , Lie Tek Tjing , Foo Gilbert , Blaabjerg Frede
Published: April 2022

The coordination of clustered microgrids (MGs) needs to be achieved in a seamless manner to tackle generation-load mismatch among MGs. A hierarchical control strategy based on PI controllers for local and global layers has been proposed in the literature to coordinate DC MGs in a cluster. However, this control strategy may not be able to resist significant load disturbances and unexpected generated powers due to the sporadic nature of the renewable energy resources. These issues are inevitable because both layers are highly dependent on PI controllers who cannot fully overcome the abovementioned obstacles. Therefore, Grey Wolf Optimizer (GWO) is proposed to enhance the performance of the global layer by optimizing its PI controller parameters. The simulation studies were conducted using the well-established MATLAB Simulink, and the results reveal that the optimized global layer performs better than the conventional ones. It is noticed that not only accurate power-sharing and proper voltage regulation within ±1% along with fewer power losses are achieved by adopting the modified consensus algorithm for the clustered DC MGs, but also the settling time and overshoot/undershoot are reduced even with the enormous load and generation changes which indicates the effectiveness of the proposed method used in the paper.
Global Maximum Power Point Tracking of Photovoltaic Module Arrays Based on Improved Cuckoo Search Algorithm
Authors: Chao Kuei-Hsiang , Chang Long-Yi , Wang Kuan-Wen
Published: April 2022

In this paper, an improved cuckoo search-learning-based optimization algorithm (CSLBOA) for the maximum power point tracking (MPPT) of a photovoltaic module array is presented. For any shading discovered on a photovoltaic module array, there will be more than one maximum power point (MPP) observed in the power–voltage (P–V) characteristic curve of the photovoltaic module array. However, only the local maximum power point (LMPP) can be tracked by the traditional maximum power point tracker, but not the global maximum power point (GMPP). Therefore, in this paper, an intelligent maximum power point tracker based on an improved cuckoo search algorithm is presented to address the abovementioned issue. First, Matlab software is used to simulate the P–V characteristic curves of a photovoltaic module array with single-peak, double-peak, triple-peak, and quadruple-peak values while the photovoltaic module arrays are under different shading conditions. Second, the improved cuckoo search algorithm proposed is applied to track the global maximum power point precisely and efficiently. According to the simulation results, it shows that the improved cuckoo search algorithm has a better tracking speed response and steady-state performance than those of traditional ones.
Detecting Wind Turbine Blade Icing with a Multiscale Long Short-Term Memory Network
Authors: Wang Xiao , Zheng Zheng , Jiang Guoqian , He Qun , Xie Ping
Published: April 2022

Blade icing is one of the main problems of wind turbines installed in cold climate regions, resulting in increasing power generation loss and maintenance costs. Traditional blade icing detection methods greatly rely on dedicated sensors, such as vibration and acoustic emission sensors, which require additional installation costs and even reduce reliability due to the degradation and failures of these sensors. To deal with this challenge, this paper aims to develop a cost-effective detection system based on the existing operation data collected from the supervisory control and data acquisition (SCADA) systems which are already equipped in large-scale wind turbines. Considering that SCADA data is essentially a multivariate time series with inherent non-stationary and multiscale temporal characteristics, a new wavelet-based multiscale long short-term memory network (WaveletLSTM) approach is proposed for wind turbine blade icing detection. The proposed method incorporates wavelet-based multiscale learning into the traditional LSTM architecture and can simultaneously learn global and local temporal features of multivariate SCADA signals, which improves fault detection ability. A real case study has shown that our proposed WaveletLSTM method achieved better detection performance than the existing methods.
Performance Analysis of an Electromagnetic Frequency Regulator under Parametric Variations for Wind System Applications
Authors: do Nascimento Thiago F. , Nunes Evandro A. D. F. , Villarreal Elmer R. L. , Pinheiro Ricardo F. , Salazar Andrés O.
Published: April 2022

The electromagnetic frequency regulator (EFR) device has proven to be an attractive solution for driving grid-connected electrical generators in distributed generation (DG) systems based on renewable energy sources (RES). However, the dynamic characteristic of the EFR has not yet been discussed for cases where its parameters vary from the nominal values. To evaluate this issue, this paper proposes a method for transient and steady-state performance analysis applied to the EFR device considering parametric variations. To perform this analysis, a dynamic model of the EFR device is derived, and its dynamic characteristics are discussed. Based on this model, the system’s controller gains are designed by using the root-locus method (RLM) to obtain the desired dynamic performance. Then, a sensitivity analysis of the closed-loop poles under the effect of parameters variation is performed. In addition, the paper also presents an analysis of the EFR-based system operating with the designed controllers. The proposed theoretical analysis is assessed using simulation and experimental results. The simulation program was developed using a Matlab/Simulink platform, while the experimental results were obtained through a laboratory setup emulating the EFR-based system.
A Novel Structure of Electromagnetic Lead Screw for Wave Energy Converter
Authors: Zhu Lixun , Ma Chao , Li Wei
Published: April 2022

A magnetic lead screw (MLS) is a device that can help a wave energy converter (WEC) to transform the low-speed linear wave motion into high-speed rotary motion with no frictional contact. However, the dynamic performance of the MLS is insufficient because only the permanent magnet (PM) is used to couple the magnetic field between the rotor and mover. To improve the dynamic performance of the MLS, a novel structure of an electromagnetic lead screw (EMLS) for the application of a WEC is proposed in this paper. In the proposed EMLS, a helical-shaped PM is mounted on the inner side of the rotor, which is as same as the traditional MLS. However, helical-shaped slots are grooved on the surface of the mover, and two-phase helical-shaped AC winding is placed in these slots to generate the controlled helical-shaped magnetic field. In this paper, the topology and the operating theory are introduced firstly. Then, the three- and its corresponding two-dimensional axis-symmetric finite element analysis model is developed to analyze the performance of the proposed EMLS. Moreover, the design aspects are presented for the realization of the proposed EMLS. Then, the performance of the proposed EMLS is compared with that of the traditional EMLS. From the results, the proposed EMLS shows larger maximum thrust force than the traditional one. Finally, the potential use value and applications in WECs of the proposed EMLS are mentioned.
Modelling of Change in Fuel Mix within a District Heating Network
Authors: Putna Ondřej , Kůdela Jakub , Krňávek Martin , Pavlas Martin , Ondra Kamil
Published: April 2022

Changing the fuel mix used in the heating industry, i.e., switching to greener fuels, is one of the possible solutions to prevent rising costs for final consumers in the context of rising emission allowance prices. This paper presents a methodology that offers the possibility to perform a comprehensive technical and economic assessment of a theoretical solution—changing the fuel mix of centralized heating sources—and other strategic decisions within a district’s heating systems. Emphasis is placed on fuels with a negative price, such as municipal waste. The presented approach can also be used to assess the effect of other significant changes related to the configuration of district heating systems on the economy of the plant, such as the impact of a decrease in heat demand and implementation of a steam turbine. The key benefit of this paper is an approach based on mathematical modelling of the operation of individual boilers with different operating parameters in terms of their start-up, shutdown, and mode of operation. A unique approach of optimizing an operation’s schedule using dynamic programming is presented, which enables the selection of a suitable solution for the configuration of binary variables in consecutive time steps. In this way, it is possible to achieve a more accurate estimate of the economics of the facility at the strategic planning stage that will consider the real operational capabilities of the heat source given its technical limitations. Using this approach, up to a 4% reduction in variable operating costs was achieved in the model case, when compared to static time interval planning.
Review of Residential Air Conditioning Systems Operating under High Ambient Temperatures
Authors: Alawadhi Mubarak , Phelan Patrick E.
Published: April 2022

This article provides an overview of residential vapor-compression air conditioners operating under high ambient temperatures (HAT). For the purpose of this article, a minimum temperature criterion, 40 °C and above, was developed to evaluate studies that were conducted at HAT. Several HAT organizations and projects were launched with the purpose of assessing the performance of low-GWP (GWP = global warming potential) refrigerants when operating under HAT and accelerating the transition to such refrigerants. Previous studies of air conditioner improvements (i.e., for condensers, evaporators, compressors, and refrigerants) were discussed under HAT conditions. This article also explores the challenges, the possible design modifications, and several limitations of air conditioners operating under HAT. Condenser improvements showed an 18 to 50% higher coefficient of performance (COP) and an 8 to 30% higher cooling capacity. Only one study was found for evaporator enhancement under HAT which improved the COP by ~7% and cooling capacity by ~10%. Experimental compressor improvements achieved 2 to 17 °C lower discharge temperature and up to 15% higher cooling capacity, whereas the COP ranged from −4% to +3% of the baseline values. Under HAT conditions, several A2L refrigerants exhibited an attractive performance compared to R-410A while none outperformed R-22 in terms of both cooling capacity and COP. Considering R-22 alternatives, all A1 refrigerants exhibited lower COP, A2L refrigerants achieved comparable COP, and A3 refrigerants reached higher COP.
Optimal Design of an Interior Permanent Magnet Synchronous Motor with Cobalt Iron Core
Authors: Bhagubai Pedro P. C. , Bucho Luís F. D. , Fernandes João F. P. , Costa Branco P. J.
Published: April 2022

The use of a cobalt-iron (VaCoFe) core is investigated as an alternative to silicon-iron (FeSi) in the design of interior permanent magnet synchronous motors (IPMSM). Considering VaCoFe and FeSi cores, a spoke-type IPMSM geometry is optimized for a torque range up to 40 N·m, providing a general comparative analysis between materials. This is done considering the application of a four-motor competition vehicle’s powertrain. A genetic optimization algorithm is coupled to the motor’s electromagnetic and thermal hybrid analytical/finite-element model to provide sufficiently accurate results within a feasible time. VaCoFe allows an estimated increase of up to 64% in torque for the same efficiency level, or up to 5% in efficiency for the same torque. After optimization and using a detailed time-dependent model, a potential 3.2% increase in efficiency, a core weight reduction of 4.1%, and a decrease of 9.6% in the motor’s core volume were found for the VaCoFe at 20 N·m. In addition, for the same motor volume, the VaCoFe allows an increase of 51.9% in torque with an increase of 1.1% in efficiency when compared with FeSi.
An Energy Storage System Composed of Photovoltaic Arrays and Batteries with Uniform Charge/Discharge
Authors: Chao Kuei-Hsiang , Huang Bing-Ze , Jian Jia-Jun
Published: April 2022

The main purpose of this study was to develop a photovoltaic module array (PVMA) and an energy storage system (ESS) with charging and discharging control for batteries to apply in grid power supply regulation of high proportions of renewable energy. To control the flow of energy at the DC load and charge/discharge the battery uniformly, this work adapted a bidirectional buck–boost soft-switching converter and the maximum power point tracking (MPPT) technique of the photovoltaic module array. First, a boost converter is used with the perturb and observe (P&O) method, so that the photovoltaic module array can work at the maximum power point (MPP) at any time. When the output power of the photovoltaic module array is greater than the load power, the excess power is used to charge the battery; on the contrary, if the output power of the photovoltaic module array is lower than the load power, the battery discharges for auxiliary power supply. This makes the voltage of the DC link maintain a constant value. The monitoring circuit sends the voltage and current signals to the TMS320F2809 digital signal processor (DSP) produced by Texas Instruments to control the battery charging/discharging voltage and current. The photovoltaic module array works at the MPP to improve the performance of the overall energy storage system. Finally, the actual test result shows that the soft-switching converter used in this work, when compared to the hard-switching converter, can improve efficiency by nearly 4% when the load power is above 125 W. When the photovoltaic power generation system operation is between 150 W and 400 W, the proposed uniform charging and discharging architecture can rapidly reach uniformity.
Microcalorimetric Study of Carbonating Produced Water as a Promising CO2 Storage and Enhanced Oil Recovery Method
Authors: Cobos Jacquelin E. , Kissami Yassin , Alkutaini Issam Abdolkareem , Søgaard Erik G.
Published: April 2022

Carbonated produced water injection (CPWI) might be considered an efficient alternative to handle the largest waste stream while enhancing the oil recovery and storing carbon dioxide (CO2) underground. This study was an attempt to get a deeper understanding of the oil recovery process through synergy between spontaneous imbibition and isothermal titration calorimetry (ITC) experiments. The results from the spontaneous imbibition experiments showed 7% to 11% additional oil recovery in comparison with plain produced water. Rock–fluid and fluid–fluid interactions, evaluated by isothermal titration calorimetry (ITC) experiments, confirmed that the CPW interactions with oil+EFB+chalk and oil+EFB systems are much more exothermic than those with plain PW in those systems. The synergy between spontaneous imbibition and ITC experiments provides an improved understanding of carbonated water injection in carbonate reservoirs.
Wildfire Rates of Spread in Grasslands under Critical Burning Conditions
Authors: Cruz Miguel G. , Alexander Martin E. , Kilinc Musa
Published: April 2022

An analysis of a dataset (n = 58) of high-intensity wildfire observations in cured grasslands from southern Australia revealed a simple relationship suitable for quickly obtaining a first approximation of a fire’s spread rate under low dead fuel moisture contents and strong wind speeds. It was found that the forward rate of fire spread is approximately 20% of the average 10-m open wind speed. The data on rate of fire spread and 10 m open wind speed ranged from 1.6 to 17 and 20 to 62 km h−1, respectively. The validity of the resulting rule of thumb was examined across a spectrum of burning conditions and its performance was contrasted against that of established empirical-based fire spread models for three different grassland fuel conditions currently used operationally in Australia. The 20% rule of thumb for grassfires produced error statistics comparable to that of the fire spread rate model for grazed or cut grass fuel conditions as recommended for general use during the summer fire season in southern Australia.
Universal Scaling Laws for Propulsive Performance of Thrust Producing Foils Undergoing Continuous or Intermittent Pitching
Authors: Das Anil , Shukla Ratnesh K. , Govardhan Raghuraman N.
Published: April 2022

High efficiency thrust generating foils are extensively being researched for potential use as thrusters in micro air vehicles and biomimetic autonomous underwater vehicles. Here, we propose a simple reduced order model for prediction of thrust generation attributes of foils that are pitched either continuously or intermittently in a periodic and possibly asymmetric fashion. Our model accounts for the distinct thrust contributions from added mass, leading edge suction, quasi steady and wake terms, all deduced from a rigorous generalization of linearized potential theory to foils undergoing small amplitude multimodal flapping motion. Additionally, the model relies on Bone-Lighthill boundary layer thinning hypothesis to account for the pitching motion induced increase in the drag force exerted on the foil. We derive generic forms of the thrust coefficient for prescribed multimodal pitching motions and specifically in the limit of large reduced frequencies, demonstrate a convergence to rather simplified scaling laws that are functions of just the Reynolds number and Strouhal number based on root mean square of the foil’s trailing edge velocity. Comparisons with previously reported experimental and simulation-based investigations demonstrate that the scaling laws capture the influence of imposed pitch on thrust generation characteristics over a range of pitching waveforms ranging from sinusoidal to square or triangular-shaped waveforms and also waveforms corresponding to intermittent pitching. The generalized relations derived in our work and the asymptotic scaling laws deduced from them are applicable to a wide spectrum of self-propulsion enabling and thrust producing waveforms including the ones that can potentially be employed in burst and coast swimming.
Radical Scavenging Activity and Physicochemical Properties of Aquafaba-Based Mayonnaises and Their Functional Ingredients
Authors: Włodarczyk Katarzyna , Zienkiewicz Agnieszka , Szydłowska-Czerniak Aleksandra
Published: April 2022

A plant-based diet has become more popular as a pathway to transition to more sustainable diets and personal health improvement in recent years. Hence, vegan mayonnaise can be proposed as an egg-free, allergy friendly vegan substitute for full-fat conventional mayonnaise. This study intends to evaluate the effect of aquafaba from chickpeas and blends of refined rapeseed oil (RRO) with different cold-pressed oils (10% of rapeseed oil—CPRO, sunflower oil—CPSO, linseed oil—CPLO or camelina oil—CPCO) on the radical scavenging, structural, emulsifying, and optical properties of novel vegan mayonnaise samples. Moreover, the functional properties and radical scavenging activity (RSA) of mayonnaise ingredients were evaluated. Aquafaba-based emulsions had a higher RSA than commercial vegan mayonnaise, determined by QUick, Easy, Novel, CHEap and Reproducible procedures using 2,2-diphenyl-1-picrylhydrazyl (QUENCHER-DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (QUENCHER-ABTS). Oxidative parameters such as peroxide values (PV), anisidine values (AnV), total oxidation (TOTOX) indexes and acid values (AV) of the proposed vegan mayonnaises were similar to those for commercial mayonnaises. Moreover, aquafaba-based samples had smaller oil droplet sizes than commercial vegan mayonnaise, which was observed using confocal laser scanning microscopy. The novel formulas developed in this study are promising alternatives to commercial vegan emulsions.
Bio-Mapping of Microbial Indicators to Establish Statistical Process Control Parameters in a Commercial Beef Processing Facility
Authors: Vargas David A. , Rodríguez Karla M. , Betancourt-Barszcz Gabriela K. , Ajcet-Reyes Manoella I. , Dogan Onay B. , Randazzo Emile , Sánchez-Plata Marcos X. , Brashears Mindy M. , Miller Markus F.
Published: April 2022

The objective was to conduct a bio-mapping of microbial indicators to determine statistical process control (SPC) parameters at a beef processing plant to establish microbiological baselines and process control parameters to support food safety management decisions. EZ-ReachTM swabs were used to collect 100 cm2 area samples at seven different locations throughout the beef processing line at four different regions on the carcass. Each of the eight sampling days evaluated included three samples collected per sampling location/carcass region for a total of 84 samples per day. Enumeration of total aerobic bacteria, Enterobacteriaceae, and Escherichia coli was performed on each sample. Microbial SPC parameters were estimated for each sampling point. Statistical differences between sampling points for all carcass locations (p < 0.001) followed an overall trend with higher values at pre- and post-evisceration with a continuous decrease until final interventions with a slight increase in counts during the chilling process and a final increase after fabrication. Variability at sampling points is the result of the nature of the process and highlights open opportunities for improvement of the food safety system. Microbial baselines and SPC parameters will help support decision making for continuous process improvement, validation of intervention schemes, and corrective action implementation for food safety management.
Addressing Knowledge Gaps for Global Climate Justice
Authors: Allam Zaheer , Jones David S. , Roös Phillip
Published: April 2022

The Conference of Parties (COP) 26 highlighted the need for global-level deep decarbonization and provided financial instruments to aid climate mitigation in the global south, as well as compensation avenues for loss and damage. This narrative reiterated the urgency of addressing climate change, as well as aiding advances in green products and green solutions whilst shifting a portion of responsibility upon the global south. While this is much needed, we argue that the science rhetoric driving this initiative continues to be advantageous to the global north due to their capacity to control consumption gaps and to access human knowledge and resource extraction. If not addressed, this will reinforce a continuing unjust north/south narrative, highlighting neo-climate colonialism precepts.